MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Annals of Biomedical Engineering' source. Tue, 07 Feb 2012 07:42:46 +0100 http://www.medworm.com/index.php?rid=5659143&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22298329%26dopt%3DAbstract Authors: Panzer MB, Myers BS, Capehart BP, Bass CR Abstract Blast-related traumatic brain injury is the most prevalent injury for combat personnel seen in the current conflicts in Iraq and Afghanistan, yet as a research community, we still do not fully understand the detailed etiology and pathology of this injury. Finite element (FE) modeling is well suited for studying the mechanical response of the head and brain to blast loading. This paper details the development of a FE head and brain model for blast simulation by examining both the dilatational and deviatoric response of the brain as potential injury mechanisms. The levels of blast exposure simulated ranged from 50 to 1000 kPa peak incident overpressure and 1-8 ms in positive-phase duration, and were comparable to real-worl... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5659143 Thu, 02 Feb 2012 05:00:00 +0100 5659143 http://www.medworm.com/index.php?rid=5659142&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22302320%26dopt%3DAbstract We describe the development of experimental platforms to quantify the regeneration of injured central nervous system (CNS) neurons by combining engineering technologies and primary neuronal cultures. Although the regeneration of CNS neurons is an important area of research, there are no currently available methods to screen for drugs. Conventional tissue culture based on Petri dish does not provide controlled microenvironment for the neurons and only provide qualitative information. In this review, we introduced the recent advances to generate in vitro model system that is capable of mimicking the niche of CNS injury and regeneration and also of testing candidate drugs. We reconstructed the microenvironment of the regeneration of CNS neurons after injury to provide as in vivo like model sy... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5659142 Wed, 01 Feb 2012 05:00:00 +0100 5659142 http://www.medworm.com/index.php?rid=5659141&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22302321%26dopt%3DAbstract Authors: Yao J, Wen C, Cheung JT, Zhang M, Hu Y, Yan C, Chiu KY, Lu WW, Fan Y Abstract Bone tunnel enlargement is a common effect associated with knee laxity after anterior cruciate ligament (ACL) reconstruction. Nevertheless, its exact pathomechanism remains controversial. One of the possible reasons could be bone remodeling due to tunnel creation, which changes the stress environment in the joint. The present study aims to characterize the deteriorated stress distribution on the articular surface, which is due to tunnel creation after single-bundle or double-bundle ACL reconstruction. The stress distributions in the knee following ACL reconstruction under the compression, rotation, and valgus torques were calculated using a validated three-dimensional finite element (FE) model. T... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5659141 Wed, 01 Feb 2012 05:00:00 +0100 5659141 http://www.medworm.com/index.php?rid=5659145&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22290588%26dopt%3DAbstract Authors: Hall CL, Zaman FS Abstract Implantation of vascular grafts or stents causes significant injury to the vessel wall. Activated coagulation factors, such as FXa are generated at the injury site. The size of the injury and the flow conditions influence the transport of these activated factors. A simulation model has been developed to evaluate surface bound coagulation inhibitors on medical devices. Tissue factor pathway inhibitor (TFPI) is a potent inhibitor of FXa in vivo. This physiologically relevant in vitro model studies the mechanism by which immobilized rTFPI effectively inhibits TF initiated thrombosis. Computational fluid dynamics was used to develop the model and validated by experiments performed in a parallel plate flow chamber. The lower plate was divided into two... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5659145 Tue, 31 Jan 2012 05:00:00 +0100 5659145 http://www.medworm.com/index.php?rid=5659144&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22290589%26dopt%3DAbstract Authors: PMID: 22290589 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5659144 Tue, 31 Jan 2012 05:00:00 +0100 5659144 http://www.medworm.com/index.php?rid=5659146&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286899%26dopt%3DAbstract Authors: Elson D, Anvari B PMID: 22286899 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5659146 Sat, 28 Jan 2012 05:00:00 +0100 5659146 http://www.medworm.com/index.php?rid=5659147&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22273730%26dopt%3DAbstract This article presents an overview of time-resolved (lifetime) fluorescence techniques used in biomedical diagnostics. In particular, we review the development of time-resolved fluorescence spectroscopy (TRFS) and fluorescence lifetime imaging (FLIM) instrumentation and associated methodologies which allow in vivo characterization and diagnosis of biological tissues. Emphasis is placed on the translational research potential of these techniques and on evaluating whether intrinsic fluorescence signals provide useful contrast for the diagnosis of human diseases including cancer (gastrointestinal tract, lung, head and neck, and brain), skin and eye diseases, and atherosclerotic cardiovascular disease. PMID: 22273730 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineer... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5659147 Wed, 25 Jan 2012 05:00:00 +0100 5659147 http://www.medworm.com/index.php?rid=5659149&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22271244%26dopt%3DAbstract Authors: Chase SD, Magnani JL, Simon SI Abstract Application of mechanical force to bonds between selectins and their ligands is a requirement for these adhesion receptors to optimally perform functions that include leukocyte tethering and activation of stable adhesion. Although all three selectins are reported to signal from the outside-in subsequent to ligand binding, E-selectin is unique in its capacity to bind multiple sialyl Lewis x presenting ligands and mediate slow rolling on the order of a micron per second. A diverse set of ligands are recognized by E-selectin in the mouse, including ESL-1, CD44 (HCELL), and PSGL-1 which are critical in transition from slow rolling to arrest and for efficient transendothelial migration. The molecular recognition process is different in hu... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5659149 Tue, 24 Jan 2012 05:00:00 +0100 5659149 http://www.medworm.com/index.php?rid=5659148&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22271245%26dopt%3DAbstract Authors: Long C, Finch C, Esch M, Anderson W, Shuler M, Hickman J Abstract Microreactors experience significant deviations from plug flow due to the no-slip boundary condition at the walls of the chamber. The development of stagnation zones leads to widening of the residence time distribution at the outlet of the reactor. A hybrid design optimization process that combines modeling and experiments has been utilized to minimize the width of the residence time distribution in a microreactor. The process was used to optimize the design of a microfluidic system for an in vitro model of the lung alveolus. Circular chambers to accommodate commercial membrane supported cell constructs are a particularly challenging geometry in which to achieve a uniform residence time distribution. Iterati... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5659148 Tue, 24 Jan 2012 05:00:00 +0100 5659148 http://www.medworm.com/index.php?rid=5623253&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22258886%26dopt%3DAbstract Authors: Olson JL, Shandas R, Erlanger M Abstract Suturing in space-confined surgical settings encountered during microsurgical procedures can be technically complex and time intensive. This paper presents the development of a new injector and new shape-memory alloy clip that can replace conventional suture. Engineering and surgical assessments of the injector and clips were performed. A prototype of the delivery system was tested in simulated surgical settings and compared to conventional suturing techniques for surgical time and wound strength. In various micro-surgical scenarios, the new injectable system proved to be 5 to 20-times more efficient and to have wound strengths over three-times that of conventional suturing. Further, the wounds closed by the shape-memory alloy clips... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5623253 Thu, 19 Jan 2012 05:00:00 +0100 5623253 http://www.medworm.com/index.php?rid=5623252&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22258887%26dopt%3DAbstract Authors: Kim HN, Kang DH, Kim MS, Jiao A, Kim DH, Suh KY Abstract Polymers provide a versatile platform for mimicking various aspects of physiological extracellular matrix properties such as chemical composition, rigidity, and topography for use in cell and tissue engineering applications. In this review, we provide a brief overview of patterning methods of various polymers with a particular focus on biocompatibility and processability. The materials highlighted here are widely used polymers including thermally curable polydimethyl siloxane, ultraviolet-curable polyurethane acrylate and polyethylene glycol, thermo-sensitive poly(N-isopropylacrylamide) and thermoplastic and conductive polymers. We also discuss how micro- and nanofabricated polymeric substrates of tunable elastic mod... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5623252 Thu, 19 Jan 2012 05:00:00 +0100 5623252 http://www.medworm.com/index.php?rid=5623251&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22258888%26dopt%3DAbstract Authors: Perry SW, Burke RM, Brown EB Abstract Application of two-photon microscopy (TPM) to translational and clinical cancer research has burgeoned over the last several years, as several avenues of pre-clinical research have come to fruition. In this review, we focus on two forms of TPM-two-photon excitation fluorescence microscopy, and second harmonic generation microscopy-as they have been used for investigating cancer pathology in ex vivo and in vivo human tissue. We begin with discussion of two-photon theory and instrumentation particularly as applicable to cancer research, followed by an overview of some of the relevant cancer research literature in areas that include two-photon imaging of human tissue biopsies, human skin in vivo, and the rapidly developing technology of t... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5623251 Thu, 19 Jan 2012 05:00:00 +0100 5623251 http://www.medworm.com/index.php?rid=5623250&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22258889%26dopt%3DAbstract This study provided quantitative information regarding the contributing factors of proximal femur strength and showed that such a biomechanical approach may have clinical potential in noninvasive assessment of hip fracture risk. PMID: 22258889 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5623250 Thu, 19 Jan 2012 05:00:00 +0100 5623250 http://www.medworm.com/index.php?rid=5602453&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22246469%26dopt%3DAbstract Authors: Miyawaki S, Tawhai MH, Hoffman EA, Lin CL Abstract The effect of carrier gas properties on particle transport in the human lung is investigated numerically in an imaging based airway model. The airway model consists of multi-detector row computed tomography (MDCT)-based upper and intra-thoracic central airways. The large-eddy simulation technique is adopted for simulation of transitional and turbulent flows. The image-registration-derived boundary condition is employed to match regional ventilation of the whole lung. Four different carrier gases of helium (He), a helium-oxygen mixture (He-O(2)), air, and a xenon-oxygen mixture (Xe-O(2)) are considered. A steady inspiratory flow rate of 342 mL/s is imposed at the mouthpiece inlet to mimic aerosol delivery on inspiration, r... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5602453 Sat, 14 Jan 2012 05:00:00 +0100 5602453 http://www.medworm.com/index.php?rid=5602455&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22237860%26dopt%3DAbstract Authors: Sheng ZF, Ma YL, Tong D, Fang DY, Liang QC, Liu LH, Zhang J, Liao EY Abstract Twenty-one 3.5-month-old female Sprague-Dawley rats were randomly assigned to three groups: BTX group, in which each rat received a single intramuscular injection of 2 U of Clostridium botulinum toxin (BTX) in the quadriceps femoris muscle of the right hind limb; BTX + SR group, in which each rat received a BTX injection and a dose of strontium ranelate (dose level of 625 mg/kg/day); and the control group. All the rats were killed at 9 weeks post-treatment. It was showed that BTX-induced rats a rapid loss of body weight in the first 3 weeks, after which their body weight showed a slow increase similar to that observed in the control rats. The net body weight loss was mainly attributed to mus... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5602455 Thu, 12 Jan 2012 05:00:00 +0100 5602455 http://www.medworm.com/index.php?rid=5602454&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22237861%26dopt%3DAbstract Authors: Tian L, Lammers SR, Kao PH, Albietz JA, Stenmark KR, Qi HJ, Shandas R, Hunter KS Abstract Understanding the mechanical behavior of proximal pulmonary arteries (PAs) is crucial to evaluating pulmonary vascular function and right ventricular afterload. Early and current efforts focus on these arteries' histological changes, in vivo pressure-diameter behavior and mechanical properties under in vitro mechanical testing. However, the in vivo stretch and stress states remain poorly characterized. To further understand the mechanical behavior of the proximal PAs under physiological conditions, this study computed the residual stretch and the in vivo circumferential stretch state in the main pulmonary arteries in both control and hypertensive calves by using in vitro and in vivo a... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5602454 Thu, 12 Jan 2012 05:00:00 +0100 5602454 http://www.medworm.com/index.php?rid=5602456&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22234864%26dopt%3DAbstract In this study, a highly detailed model was reconstructed from a post-mortem coronary specimen of a patient with observed VP, using high resolution micro-CT which captured the microcalcifications embedded in the fibrous cap. Fluid-structure interaction (FSI) simulations were conducted in the reconstructed model to examine the combined effects of micro-Ca, flow phase lag and plaque material properties on plaque burden and vulnerability. This dynamic fibrous cap stress mapping elucidates the contribution of micro-Ca and flow phase lag VP vulnerability independently. Micro-Ca embedded in the fibrous cap produced increased stresses predicted by previously published analytical model, and corroborated our previous studies. The 'micro-CT to FSI' methodology may offer better diagnostic tools for cl... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5602456 Wed, 11 Jan 2012 05:00:00 +0100 5602456 http://www.medworm.com/index.php?rid=5578549&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22230967%26dopt%3DAbstract In this study, using a custom-made nanoindentation device, changes to the local viscoelastic properties of porcine thoracic aorta wall due to three common storage temperatures (+4, -20, and -80 °C) within 24 h, 48 h, 1 week, and 3 weeks were characterized. The changes to both elastic and relaxation behaviors were investigated considering the multilayer, heterogeneous nature of the aortic wall. The results showed that the average instantaneous Young's modulus (E) of +4 °C storage samples decreased while their permanent average relaxation amplitude (G (∞)) increased and after 48 h these changes became significant (10 and 13% for E and G (∞), respectively). Generally, in freezer storage, E increased and G (∞) showed no significant change. In prolon... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5578549 Tue, 10 Jan 2012 05:00:00 +0100 5578549 http://www.medworm.com/index.php?rid=5578552&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22227972%26dopt%3DAbstract Authors: Nayebosadri A, Christopher L, Ji JY Abstract Endothelial cells are continuously exposed to hemodynamic shear stress, which has been shown to induce an array of physiological responses at the cellular and molecular levels. Uniform high shear stress is protective against vascular diseases such as atherosclerosis which preferentially occur at regions of disturbed flow and low shear. The glucocorticoid receptor (GR), a member of the steroid nuclear receptors with anti-inflammatory functions, has been shown to be activated by shear stress. Using a unique expectation-maximization (EM) algorithm based on Bayesian statistics, we have developed an image analysis algorithm to quantitatively assess GR nuclear translocation based on time-lapse images of green fluorescence protein-tagg... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5578552 Sat, 07 Jan 2012 05:00:00 +0100 5578552 http://www.medworm.com/index.php?rid=5578551&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22227973%26dopt%3DAbstract This study was designed to apply a simulated human in vivo motion to human knees to measure the kinetics of the human knee and ACL. In pursuit of establishing a viable biomechanical surrogate, a simulated in vivo ovine motion was also applied to human knees to compare the loads produced by the human and ovine motions. The motions from the two species produced similar kinetics in the human knee and ACL. The only significant difference was the intact knee compression force produced by the two input motions. PMID: 22227973 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5578551 Sat, 07 Jan 2012 05:00:00 +0100 5578551 http://www.medworm.com/index.php?rid=5578550&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22227974%26dopt%3DAbstract Authors: Sarantopoulos A, Beziere N, Ntziachristos V Abstract Many clinical interventional procedures, such as surgery or endoscopy, are today still guided by human vision and perception. Human vision however is not sensitive or accurate in detecting a large range of disease biomarkers, for example cellular or molecular processes characteristic of disease. For this reason advanced optical and opto-acoustic (photo-acoustic) methods are considered for enabling a more versatile, sensitive and accurate detection of disease biomarkers and complement human vision in clinical decision making during interventions. Herein, we outline developments in emerging fluorescence and opto-acoustic sensing and imaging techniques that can lead to practical implementations toward improving intervention... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5578550 Sat, 07 Jan 2012 05:00:00 +0100 5578550 http://www.medworm.com/index.php?rid=5578553&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22218702%26dopt%3DAbstract Authors: McCormick AM, Leipzig ND Abstract There are currently no acceptable cures for central nervous system injuries, and damage induced large gaps in the peripheral nervous system have been challenging to bridge to restore neural functionality. Innervation by neurons is made possible by the growth cone. This dynamic structure is unique to neurons, and can directly sense physical and chemical activity in its environment, utilizing these cues to propel axons to precisely reach their targets. Guidance can occur through chemoattractive factors such as neurotrophins and netrins, chemorepulsive agents like semaphorins and slits, or contact-mediated molecules such as ephrins and those located in the extracellular matrix. The understanding of biomolecular activity during nervous system ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5578553 Thu, 05 Jan 2012 05:00:00 +0100 5578553 http://www.medworm.com/index.php?rid=5560692&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22215275%26dopt%3DAbstract In this study, ten rabbits were treated with gel-silica loop to develop a defined local stenosis in the straight segment of the left carotid artery. Both numerical simulation and experiment measurements showed that the concentration of LDL was about 35% higher at the blood/arterial wall interface than in the lumen on the distal side of the stenosis. Atherosclerotic lesions with abundant lipid deposits were observed and stromal derived factor-1 (SDF-1) was detected at the distal end of the stenosis, while the straight segment was plaque-free. In vitro studies demonstrated that LDL-induced SDF-1 expression in endothelial cells and increased monocyte adhesion to endothelial cells in a dose-dependent manner. The adhesion was suppressed when endothelial cells were pretreated with SDF-1 antibody... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5560692 Wed, 04 Jan 2012 05:00:00 +0100 5560692 http://www.medworm.com/index.php?rid=5560691&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22215276%26dopt%3DAbstract Authors: Sung JH, Shuler ML Abstract Microtechnology provides a new approach for reproducing the in vivo environment in vitro. Mimicking the microenvironment of the natural tissues allows cultured cells to behave in a more authentic manner, and gives researchers more realistic platforms to study biological systems. In this review article, we discuss the physiochemical aspects of in vivo cellular microenvironment, and relevant technologies that can be used to mimic those aspects. Secondly we identify the core methods used in microtechnology for biomedical applications. Finally we examine the recent application areas of microtechnology, with a focus on reproducing the functions of specific organs, or whole-body response such as homeostasis or metabolism-dependent toxicity of drugs. T... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5560691 Wed, 04 Jan 2012 05:00:00 +0100 5560691 http://www.medworm.com/index.php?rid=5560690&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22215277%26dopt%3DAbstract In this study, an automated technique for the evaluation of dual p16/Ki67 immunoreactivity in cervical cell nuclei is introduced. Smears stained with p16 and Ki67 antibodies were digitized, and analyzed by algorithms we developed. Gradient-based radial symmetry operator and adaptive processing of symmetry image were employed to obtain the nuclear mask. This step was followed by the extraction of features including pixel data and immunoreactivity signature from each nucleus. The features were analyzed by two support vector machine classifiers to assign a nucleus into one of four types of immunoreactivity: p16 positive (p16(+)/Ki67(-)), Ki67 positive (p16(-)/Ki67(+)), dual p16/Ki67 positive (p16(+)/Ki67(+)) and negative (p16(-)/Ki67(-)), respectively. Results obtained by our method correlate... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5560690 Wed, 04 Jan 2012 05:00:00 +0100 5560690 http://www.medworm.com/index.php?rid=5560689&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22215278%26dopt%3DAbstract This study provides a general numerical tool to optimize the hinge design based on both hemodynamic and thromboembolic performance. PMID: 22215278 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5560689 Wed, 04 Jan 2012 05:00:00 +0100 5560689 http://www.medworm.com/index.php?rid=5550445&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22203191%26dopt%3DAbstract This study investigates whether the uncompetitive N-methyl-D: -aspartic acid receptor antagonist, memantine, is able to protect dissociated cortical neurons from glutamate-induced excitotoxicity (GIE). Treatment with glutamate resulted in a significant loss of synchronization of neuronal activity as well as a significant increase in the duration of synchronized bursting events (SBEs). By administering memantine at the same time as glutamate, we were able to completely prevent these changes to the neuronal activity. Pretreatment with memantine was somewhat effective in preventing changes to the culture synchronization but was unable to fully protect the synchronization of electrical activity between neurons that showed high levels of synchronization prior to injury. Additionally, memantine ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5550445 Wed, 28 Dec 2011 05:00:00 +0100 5550445 http://www.medworm.com/index.php?rid=5550444&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22203192%26dopt%3DAbstract In this study we subjected 3T3-L1 preadipocytes cultured on elastic substrata to different levels of static equiaxial tensile strains within the physiological range, up to substrate tensile strain (STS) of 12%, while inducing differentiation in the cultures. Based on prior work which revealed that adipogenesis is accelerated in cultures subjected to STS of 12% by activating the mitogen-activated protein kinase kinase signaling pathway, we were specifically interested in identifying the STS levels which trigger this process. We hence monitored the production and accumulation of lipid droplets (LDs) using a non-destructive, image-processing-based method that we have previously developed, for a period of 4 weeks. The experimental data demonstrated accelerated adipogenesis in the cultures subj... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5550444 Wed, 28 Dec 2011 05:00:00 +0100 5550444 http://www.medworm.com/index.php?rid=5550446&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22198135%26dopt%3DAbstract Authors: Votta E, Paroni L, Conti CA, Pelosi A, Mangini A, D'Alesio P, Vismara R, Antona C, Redaelli A Abstract Recently, the neo-chordae technique (NCT) was proposed to stabilize the surgical correction of isolated aortic valve (AV) prolapse. Neo-chordae are inserted into the corrected leaflet to drive its closure by minimal tensions and prevent relapses. In a previous in vitro study we analysed the NCT effects on healthy aortic roots (ARs). Here we extend that analysis via finite element models (FEMs). After successfully replicating the experimental conditions for validation purposes, we modified our AR FEM, obtaining a continent AV with minor isolated prolapse, thus representing a realistic clinical scenario. We then simulated the NCT, and systematically assessed the acute effec... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5550446 Sun, 25 Dec 2011 05:00:00 +0100 5550446 http://www.medworm.com/index.php?rid=5535307&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22189490%26dopt%3DAbstract Authors: Kim BJ, Wu M Abstract The emerging field of micro-technology has opened up new possibilities for exploring cellular chemotaxis in real space and time, and at single cell resolution. Chemotactic cells sense and move in response to chemical gradients and play important roles in a number of physiological and pathological processes, including development, immune responses, and tumor cell invasions. Due to the size proximity of the microfluidic device to cells, microfluidic chemotaxis devices advance the traditional macro-scale chemotaxis assays in two major directions: one is to build well defined and stable chemical gradients at cellular length scales, and the other is to provide a platform for quantifying cellular responses at both cellular and molecular levels using advance... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535307 Thu, 22 Dec 2011 05:00:00 +0100 5535307 http://www.medworm.com/index.php?rid=5535306&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22189491%26dopt%3DAbstract Authors: Trujillo M, Ribera V, Quesada R, Berjano E Abstract Radiofrequency (RF) thermokeratoplasty uses RF currents to alter the curvature of the cornea by means of thermal lesions. An RF applicator which combined a microkeratome suction ring and a circular electrode was designed with the aim of creating circular thermal lesions in a predictable, uniform and safe way. An experimental study was conducted on ex vivo porcine eyes. A theoretical model was also designed. The experimental results showed a lesion depth of 34.2 ± 11.0% of corneal thickness at a constant voltage of 50 V up to roll-off (1000 Ω of impedance). With a voltage of 30 V for 30 s the mean depth was 36.8 ± 8.1%. The progress of electrical impedance throughout heating and lesion dimensions were used to c... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535306 Thu, 22 Dec 2011 05:00:00 +0100 5535306 http://www.medworm.com/index.php?rid=5535305&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22189492%26dopt%3DAbstract Authors: Fouras A, Allison BJ, Kitchen MJ, Dubsky S, Nguyen J, Hourigan K, Siu KK, Lewis RA, Wallace MJ, Hooper SB Abstract Since lung diseases adversely affect airflow during breathing, they must also alter normal lung motion, which can be exploited to detect these diseases. However, standard imaging techniques such as CT and MRI imaging during breath-holds provide little or no information on lung motion and cannot detect diseases that cause subtle changes in lung structure. Phase-contrast X-ray imaging provides images of high contrast and spatial resolution with temporal resolutions that allow multiple images to be acquired throughout the respiratory cycle. Using X-ray phase-contrast imaging, coupled with velocimetry, we have measured lung tissue movement and determined velocity ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535305 Thu, 22 Dec 2011 05:00:00 +0100 5535305 http://www.medworm.com/index.php?rid=5535308&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22187136%26dopt%3DAbstract Authors: Hasson CJ, Caldwell GE Abstract Redundancy in the human muscular system makes it challenging to assess age-related changes in muscle mechanical properties in vivo, as ethical considerations prohibit direct muscle force measurement. We overcame this by using a hybrid approach that combined magnetic resonance and ultrasound imaging, dynamometer measurements, muscle modeling, and numerical optimization to obtain subject-specific estimates of the mechanical properties of tibialis anterior, gastrocnemius, and soleus muscles from young and older adults. We hypothesized that older subjects would have lower maximal isometric forces, slower contractile and stiffer elastic characteristics, and that subject-specific muscle properties would give more accurate joint torque predictions ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535308 Wed, 21 Dec 2011 05:00:00 +0100 5535308 http://www.medworm.com/index.php?rid=5535309&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22183194%26dopt%3DAbstract This study found that collagen fiber re-alignment depends on developmental age and suggests that collagen fibrillogenesis may influence the tendon's ability to structurally respond to load. Additionally, results indicate that the insertion site and tendon midsubstance locations develop differently. PMID: 22183194 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535309 Tue, 20 Dec 2011 05:00:00 +0100 5535309 http://www.medworm.com/index.php?rid=5535310&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22179683%26dopt%3DAbstract Authors: Ergun A, Chung R, Ward D, Valdevit A, Ritter A, Kalyon DM Abstract A unitary bioresorbable cage/core bone graft substitute consisting of a stiff cage and a softer core with interconnected porosity is offered for spinal arthrodesis. Polycaprolactone, PCL, was used as the matrix and hydroxyapatite, HA, and β-tricalcium phosphate, TCP, were used in the formulation of the cage layer to impart modulus increase and osteoconductivity while the core consisted solely of PCL. The crystallinity, biodegradation rate (under accelerated conditions) and mechanical properties, i.e., the uniaxial compression, relaxation modulus upon step compression and cyclic compressive fatigue properties, of the co-extruded cage/core bone graft substitutes could be manipulated by changes in the concent... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535310 Sat, 17 Dec 2011 05:00:00 +0100 5535310 http://www.medworm.com/index.php?rid=5535311&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22173558%26dopt%3DAbstract In conclusion, non-contrast cardiac CT imaging can be successfully employed to assess thoracic aorta 3D morphometry. PMID: 22173558 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535311 Fri, 16 Dec 2011 05:00:00 +0100 5535311 http://www.medworm.com/index.php?rid=5535312&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22167531%26dopt%3DAbstract Authors: Chbat NW, Chu W, Ghosh M, Li G, Li M, Chiofolo CM, Vairavan S, Herasevich V, Gajic O Abstract Acute lung injury (ALI) is a devastating complication of acute illness and one of the leading causes of multiple organ failure and mortality in the intensive care unit (ICU). The detection of this syndrome is limited due to the complexity of the disease, insufficient understanding of its development and progression, and the large amount of risk factors and modifiers. In this preliminary study, we present a novel mathematical model for ALI detection. It is constructed based on clinical and research knowledge using three complementary techniques: rule-based fuzzy inference systems, Bayesian networks, and finite state machines. The model is developed in Matlab(®)'s Simulink environm... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535312 Wed, 14 Dec 2011 05:00:00 +0100 5535312 http://www.medworm.com/index.php?rid=5535315&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22160577%26dopt%3DAbstract Authors: Prot JM, Leclerc E Abstract In this paper, we will consider new in vitro cell culture platforms and the progress made, based on the microfluidic liver biochips dedicated to pharmacological and toxicological studies. Particular emphasis will be given to recent developments in the microfluidic tools dedicated to cell culture (more particularly liver cell culture), in silico opportunities for Physiologically Based PharmacoKinetic (PBPK) modelling, the challenge of the mechanistic interpretations offered by the approaches resulting from "multi-omics" data (transcriptomics, proteomics, metabolomics, cytomics) and imaging microfluidic platforms. Finally, we will discuss the critical features regarding microfabrication, design and materials, and cell functionality as the key poin... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535315 Sat, 10 Dec 2011 05:00:00 +0100 5535315 http://www.medworm.com/index.php?rid=5535314&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22160578%26dopt%3DAbstract Authors: Gambaruto AM, Taylor DJ, Doorly DJ Abstract Patient-specific studies of physiological flows rely on anatomically realistic or idealized models. Objective comparison of datasets or the relation of specific to idealized geometries has largely been performed in an ad hoc manner. Here, two rational procedures (based respectively on Fourier descriptors and medial axis (MA) transforms) are presented; each provides a compact representation of a complex anatomical region, specifically the nasal airways. The techniques are extended to furnish average geometries. These retain a sensible anatomical form, facilitating the identification of a specific anatomy as a set of weighted perturbations about the average. Both representations enable a rapid translation of the surface description... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535314 Sat, 10 Dec 2011 05:00:00 +0100 5535314 http://www.medworm.com/index.php?rid=5535313&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22160600%26dopt%3DAbstract In conclusion, we developed a biomaterial that increases and decreases in stiffness while contracting and expanding, respectively. We found that the dynamic deformation directionality of the matrix determined the fibroblast morphology and possibly influences function. PMID: 22160600 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535313 Thu, 08 Dec 2011 05:00:00 +0100 5535313 http://www.medworm.com/index.php?rid=5535316&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22146901%26dopt%3DAbstract Authors: Wang JH, Wang CH, Lee GB Abstract Recently, micro-electro-mechanical-systems (MEMS) technology and micromachining techniques have enabled miniaturization of biomedical devices and systems. Not only do these techniques facilitate the development of miniaturized instrumentation for biomedical analysis, but they also open a new era for integration of microdevices for performing accurate and sensitive diagnostic assays. A so-called "micro-total-analysis-system", which integrates sample pretreatment, transport, reaction, and detection on a small chip in an automatic format, can be realized by combining functional microfluidic components manufactured by specific MEMS technologies. Among the promising applications using microfluidic technologies, nucleic acid-based detection has ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535316 Wed, 07 Dec 2011 05:00:00 +0100 5535316 http://www.medworm.com/index.php?rid=5535318&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22143598%26dopt%3DAbstract Authors: Kelly CV, Craighead HG Abstract Recent advancements and applications of nanofabrication have enabled the characterization and control of biological membranes at submicron scales. This review focuses on the application of nanofabrication towards the nanoscale observing, patterning, sorting, and concentrating membrane components. Membranes on living cells are a necessary component of many fundamental cellular processes that naturally incorporate nanoscale rearrangement of the membrane lipids and proteins. Nanofabrication has advanced these understandings, for example, by providing 30 nm resolution of membrane proteins with metal-enhanced fluorescence at the tip of a scanning probe on fixed cells. Naturally diffusing single molecules at high concentrations on live cells have... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535318 Tue, 06 Dec 2011 05:00:00 +0100 5535318 http://www.medworm.com/index.php?rid=5535317&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22143599%26dopt%3DAbstract In this study, we demonstrate high resolution spatiotemporal imaging of inflammation in mice treated with systemic injection of lipopolysaccharides (LPS) to mimic systemic inflammatory response or sepsis. Diagnosis of organ-level inflammation was achieved by magnetic resonance imaging (MRI) of inflammation-sensitive superparamagnetic iron oxide (SPIO)-based nanomicelle termed leukocyte-mimetic nanoparticle (LMN), designed to preferentially localize to cells with inflammation-induced overexpression of intercellular adhesion molecule (ICAM)-1. Using a novel MRI quantitative susceptibility mapping (QSM) technique for non-invasive quantification of SPIO nanoparticles, we observed greater accumulation of LMN in the liver, specific to ICAM-1 induction due to LPS-induced inflammation. However, th... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535317 Tue, 06 Dec 2011 05:00:00 +0100 5535317 http://www.medworm.com/index.php?rid=5535319&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22139396%26dopt%3DAbstract Authors: Rasmussen JC, Kwon S, Sevick-Muraca EM, Cormier JN Abstract The lymphatic system is the secondary circulatory system responsible for fluid homeostasis and protein transport in the body. In addition, because the lymphatic system provides a primary pathway for cancer metastasis, lymph node involvement is routinely used as a determinant in cancer staging. Despite their importance, the lymphatics remain poorly understood, in part because of the historic lack of imaging modalities with sufficient spatial and/or temporal resolution to visualize the fine lymphatic structure and subtle contractile function. In recent years, near-infrared fluorescence (NIRF) imaging has emerged as a new imaging modality to non-invasively visualize the lymphatics and assess contractile lymphatic fun... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535319 Sat, 03 Dec 2011 05:00:00 +0100 5535319 http://www.medworm.com/index.php?rid=5535321&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22134466%26dopt%3DAbstract Authors: Young JK, Figueroa ER, Drezek RA Abstract The theranostic potential of several nanostructures has been discussed in the context of photothermal therapies and imaging. In the last several decades, the burden of cancer has grown rapidly, making the need for new theranostic approaches vital. Lasers have emerged as promising tools in cancer treatment, especially with the advent of photothermal therapies wherein light absorbing dyes or plasmonic gold nanoparticles are used to generate heat and achieve tumor damage. Recently, photoabsorbing nanostructures have materialized that can be employed in conjunction with lasers in the near-infrared region in order to enhance both imaging and photothermal effects. The incorporation of tunable nanostructures has resulted in improved speci... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535321 Fri, 02 Dec 2011 05:00:00 +0100 5535321 http://www.medworm.com/index.php?rid=5535320&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22134467%26dopt%3DAbstract Authors: Parijat P, Lockhart TE Abstract Identifying effective interventions is vital in preventing slip-induced fall accidents in older adults. The purpose of the current study was to evaluate the efficacy of moveable platform training in improving recovery reactions and reducing fall frequency in older adults. Twenty-four older adults were recruited and randomly assigned to two groups (training and control). Both groups underwent three sessions including baseline slip, training, and transfer of training on a slippery surface. Both groups experienced two slips on a slippery surface, one during the baseline and the other (after 2 weeks) during the transfer of training session. In the training session, the training group underwent twelve simulated slips using a moveable platform wh... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535320 Fri, 02 Dec 2011 05:00:00 +0100 5535320 http://www.medworm.com/index.php?rid=5535322&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22130636%26dopt%3DAbstract The objective of this study was to identify the effect of a saddle-shaped annulus on native tricuspid leaflet stretch mechanics and TR. In addition, the effects of geometric alterations, including annular dilatation and PM displacement, on leaflet stretch was investigated. Fresh porcine tricuspid valves (TVs) (n = 8) were excised and sutured to an adjustable three-dimensional annulus plate (allowing for dilatation and saddle-shape) and three PM attachment rods. The valve was then placed in the in vitro Georgia Tech right heart simulator. Dual-camera photogrammetry, was used to quantify the stretch ratio experienced by the valve leaflets at peak systole for the following conditions: physiologically normal, 100% annular dilatation, displaced PMs, and a combination of annular dilatation and... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5535322 Thu, 01 Dec 2011 05:00:00 +0100 5535322 http://www.medworm.com/index.php?rid=5380116&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21984513%26dopt%3DAbstract This study tested for kinematic differences at the lower back, shoulder, elbow, wrist, and racquet between the flat, kick, and slice serves using a markerless motion capture (MMC) system. Seven male NCAA Division 1 players were tested on an outdoor court in daylight conditions. Peak racquet and joint center speeds occurred sequentially and increased from proximal (back) to distal (racquet). Racquet speeds at ball impact were not significantly different between serve types. However, there were significant differences in the direction of the racquet velocity vector between serves: the kick serve had the largest lateral and smallest forward racquet velocity components, while the flat serve had the smallest vertical component (p < 0.01). The slice serve had lateral velocity, like the kick... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380116 Sun, 06 Nov 2011 22:13:02 +0100 5380116 http://www.medworm.com/index.php?rid=5380106&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21994063%26dopt%3DAbstract This article presents an integrated, automatic home-monitoring, and assist system for patients suffering from end-stage heart failure, particularly patients with implanted mechanical circulatory support devices, such as ventricular assist devices and total artificial hearts. The system incorporates various biosensors to monitor the vital parameters of the patient unobtrusively in the home environment. Recorded data can be accessed online and in real time by a supervising physician, and these data serve as a means for immediate diagnosis of emergency events. The retrieved information can also be continuously analyzed to generate suggestions for medication, nutrition, and exercise for the patient to optimize their rehabilitation and overall health. An experimental environment (the Future Car... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380106 Sun, 06 Nov 2011 22:09:34 +0100 5380106 http://www.medworm.com/index.php?rid=5380065&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22052157%26dopt%3DAbstract A Novel Frequency Analysis Method for Assessing K(ir)2.1 and Na (v)1.5 Currents. Ann Biomed Eng. 2011 Nov 4; Authors: Rigby JR, Poelzing S Abstract Voltage clamping is an important tool for measuring individual currents from an electrically active cell. However, it is difficult to isolate individual currents without pharmacological or voltage inhibition. Herein, we present a technique that involves inserting a noise function into a standard voltage step protocol, which allows one to characterize the unique frequency response of an ion channel at different step potentials. Specifically, we compute the fast Fourier transform for a family of current traces at different step potentials for the inward rectifying potassium channel, K(ir)2.1, and the channel encoding the cardi... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380065 Fri, 04 Nov 2011 04:00:00 +0100 5380065 http://www.medworm.com/index.php?rid=5380066&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22048668%26dopt%3DAbstract Authors: Luke GP, Yeager D, Emelianov SY Abstract Photoacoustic imaging is a biomedical imaging modality that provides functional information, and, with the help of exogenous contrast agents, cellular and molecular signatures of tissue. In this article, we review the biomedical applications of photoacoustic imaging assisted with exogenous contrast agents. Dyes, noble metal nanoparticles, and other constructs are contrast agents which absorb strongly in the near-infrared band of the optical spectrum and generate strong photoacoustic response. These contrast agents, which can be specifically targeted to molecules or cells, have been coupled with photoacoustic imaging for preclinical and clinical applications ranging from detection of cancer cells, sentinel lymph nodes, and micrometas... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380066 Thu, 03 Nov 2011 04:00:00 +0100 5380066 http://www.medworm.com/index.php?rid=5380068&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22045510%26dopt%3DAbstract Authors: Silva Z, Konstantopoulos K, Videira PA Abstract Dendritic cells (DCs) are crucial components of the immune response, strategically positioned as immune sentinels. Complex trafficking and accurate positioning of DCs are indispensable for both immunity and tolerance. This is particularly evident for their therapeutic application where an unmet clinical need exists for DCs with improved migratory capacity upon adoptive transfer into patients. One critical step that directs the trafficking of DCs throughout the body is their egress from the vasculature, starting with their adhesive interactions with vascular endothelium under shear flow. Both tethering and rolling rely on interactions mediated by specific glycans attached to glycoproteins and glycolipids present on the DC surf... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380068 Wed, 02 Nov 2011 04:00:00 +0100 5380068 http://www.medworm.com/index.php?rid=5380067&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22045511%26dopt%3DAbstract Authors: Chung H, Dai T, Sharma SK, Huang YY, Carroll JD, Hamblin MR Abstract Soon after the discovery of lasers in the 1960s it was realized that laser therapy had the potential to improve wound healing and reduce pain, inflammation and swelling. In recent years the field sometimes known as photobiomodulation has broadened to include light-emitting diodes and other light sources, and the range of wavelengths used now includes many in the red and near infrared. The term "low level laser therapy" or LLLT has become widely recognized and implies the existence of the biphasic dose response or the Arndt-Schulz curve. This review will cover the mechanisms of action of LLLT at a cellular and at a tissular level and will summarize the various light sources and principles of dosimetry that... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380067 Wed, 02 Nov 2011 04:00:00 +0100 5380067 http://www.medworm.com/index.php?rid=5380072&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22037949%26dopt%3DAbstract Authors: Almaraz RT, Mathew MP, Tan E, Yarema KJ Abstract Metabolic oligosaccharide engineering is an emerging technology wherein non-natural monosaccharide analogs are exogenously supplied to living cells and are biosynthetically incorporated into cell surface glycans. A recently reported application of this methodology employs fluorinated analogs of ManNAc, GlcNAc, and GalNAc to modulate selectin-mediated adhesion associated with leukocyte extravasation and cancer cell metastasis. This monograph outlines possible mechanisms underlying the altered adhesion observed in analog-treated cells; these range from the most straightforward explanation (e.g., structural changes to the selectin ligands ablate interaction with their receptors) to the alternative mechanism where the analogs in... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380072 Sun, 30 Oct 2011 04:00:00 +0100 5380072 http://www.medworm.com/index.php?rid=5380069&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22042626%26dopt%3DAbstract Authors: Goral VN, Yuen PK Abstract In this article, we summarize the key elements of microfluidic platforms for mimicking in vivo hepatocyte cell culture and the major recent advances in this area. Specifically, we will give brief background and rationale for key design requirements for mimicking in vivo hepatocyte cell culture, and then summarize findings, applications, and limitations from microfluidic platforms that addressed these design requirements. Although no ideal microfluidic platform has so far been developed for fully mimicking in vivo hepatocyte cell culture, some approaches and designs have demonstrated great potential in this area. PMID: 22042626 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380069 Sat, 29 Oct 2011 04:00:00 +0100 5380069 http://www.medworm.com/index.php?rid=5380070&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22042625%26dopt%3DAbstract Authors: Shazly T, Kolachalama VB, Ferdous J, Oberhauser JP, Hossainy S, Edelman ER Abstract Fully bioresorbable vascular scaffolds (BVS) are attractive platforms for the treatment of ischemic artery disease owing to their intrinsic ability to uncage the treated vessel after the initial scaffolding phase, thereby allowing for the physiological conditioning that is essential to cellular function and vessel healing. Although scaffold erosion confers distinct advantages over permanent endovascular devices, high transient by-product concentrations within the arterial wall could induce inflammatory and immune responses. To better understand these risks, we developed in this study an integrated computational model that characterizes the bulk degradation and by-product fate for a represen... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380070 Wed, 26 Oct 2011 04:00:00 +0100 5380070 http://www.medworm.com/index.php?rid=5380073&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22037916%26dopt%3DAbstract Authors: Rausch MK, Bothe W, Kvitting JP, Swanson JC, Miller DC, Kuhl E Abstract Mitral valve annuloplasty is a common surgical technique used in the repair of a leaking valve by implanting an annuloplasty device. To enhance repair durability, these devices are designed to increase leaflet coaptation, while preserving the native annular shape and motion; however, the precise impact of device implantation on annular deformation, strain, and curvature is unknown. In this article, we quantify how three frequently used devices significantly impair native annular dynamics. In controlled in vivo experiments, we surgically implanted 11 flexible-incomplete, 11 semi-rigid-complete, and 12 rigid-complete devices around the mitral annuli of 34 sheep, each tagged with 16 equally spaced tantalu... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380073 Tue, 25 Oct 2011 04:00:00 +0100 5380073 http://www.medworm.com/index.php?rid=5380071&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22042624%26dopt%3DAbstract Authors: Salek MM, Sattari P, Martinuzzi RJ Abstract The appearance of highly resistant bacterial biofilms in both community and hospitals environments is a major challenge in modern clinical medicine. The biofilm structural morphology, believed to be an important factor affecting the behavioral properties of these "super bugs", is strongly influenced by the local hydrodynamics over the microcolonies. Despite the common use of agitated well plates in the biology community, they have been used rather blindly without knowing the flow characteristics and influence of the rotational speed and fluid volume in these containers. The main purpose of this study is to characterize the flow in these high-throughput devices to link local hydrodynamics to observed behavior in cell cultures. In ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380071 Tue, 25 Oct 2011 04:00:00 +0100 5380071 http://www.medworm.com/index.php?rid=5380077&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22016324%26dopt%3DAbstract Authors: Aguilar G, Choi B, Broekgaarden M, Yang O, Yang B, Ghasri P, Chen JK, Bezemer R, Nelson JS, van Drooge AM, Wolkerstorfer A, Kelly KM, Heger M Abstract During the last three decades, several laser systems, ancillary technologies, and treatment modalities have been developed for the treatment of port wine stains (PWSs). However, approximately half of the PWS patient population responds suboptimally to laser treatment. Consequently, novel treatment modalities and therapeutic techniques/strategies are required to improve PWS treatment efficacy. This overview therefore focuses on three distinct experimental approaches for the optimization of PWS laser treatment. The approaches are addressed from the perspective of mechanical engineering (the use of local hypobaric pressure to i... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380077 Fri, 21 Oct 2011 04:00:00 +0100 5380077 http://www.medworm.com/index.php?rid=5380076&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22016325%26dopt%3DAbstract Authors: Michaelson JE, Huang H Abstract Cell-cell junctional proteins play important structural and functional roles in several physiological systems. Recent studies have illuminated key aspects in the relationship of junctional proteins with normal cell and tissue function as well as various pathologies. In this review article, the roles of cell-cell junctional proteins will be presented in four classes: adherens junctions, desmosomes, gap junctions, and tight junctions, and discussed primarily in the context of cardiovascular cell and tissue physiology and pathophysiology. The functions of the proteins are described from the perspective of mechanotransductive regulation of physiological and disease processes, with focus being laid on more biomechanical aspects, such as cell adhe... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380076 Fri, 21 Oct 2011 04:00:00 +0100 5380076 http://www.medworm.com/index.php?rid=5380075&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22016326%26dopt%3DAbstract Authors: Reymond P, Westerhof N, Stergiopulos N Abstract Decrease in arterial compliance leads to an increased pulse pressure, as explained by the Windkessel effect. Pressure waveform is the sum of a forward running and a backward running or reflected pressure wave. When the arterial system stiffens, as a result of aging or disease, both the forward and reflected waves are altered and contribute to a greater or lesser degree to the increase in aortic pulse pressure. Two mechanisms have been proposed in the literature to explain systolic hypertension upon arterial stiffening. The most popular one is based on the augmentation and earlier arrival of reflected waves. The second mechanism is based on the augmentation of the forward wave, as a result of an increase of the characteristic ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380075 Fri, 21 Oct 2011 04:00:00 +0100 5380075 http://www.medworm.com/index.php?rid=5380074&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22016327%26dopt%3DAbstract Authors: Arzani A, Dyverfeldt P, Ebbers T, Shadden SC Abstract This paper compares numerical predictions of turbulence intensity with in vivo measurement. Magnetic resonance imaging (MRI) was carried out on a 60-year-old female with a restenosed aortic coarctation. Time-resolved three-directional phase-contrast (PC) MRI data was acquired to enable turbulence intensity estimation. A contrast-enhanced MR angiography (MRA) and a time-resolved 2D PCMRI measurement were also performed to acquire data needed to perform subsequent image-based computational fluid dynamics (CFD) modeling. A 3D model of the aortic coarctation and surrounding vasculature was constructed from the MRA data, and physiologic boundary conditions were modeled to match 2D PCMRI and pressure pulse measurements. Blood... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380074 Fri, 21 Oct 2011 04:00:00 +0100 5380074 http://www.medworm.com/index.php?rid=5380086&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22012079%26dopt%3DAbstract Authors: Viano DC, Withnall C, Halstead D Abstract Linear impact tests were conducted on 17 modern football helmets. The helmets were placed on the Hybrid III head with the neck attached to a sliding table. The head was instrumented with an array of 3-2-2-2 accelerometers to determine translational acceleration, rotational acceleration, and HIC. Twenty-three (23) different impacts were conducted on four identical helmets of each model at eight sites on the shell and facemask, four speeds (5.5, 7.4, 9.3, and 11.2 m/s) and two temperatures (22.2 and 37.8 °C). There were 1,850 tests in total; 276 established the 1990s helmet performance (baseline) and 1,564 were on the 17 different helmet models. Differences from the 1990s baseline were evaluated using the Student t test (p < ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380086 Thu, 20 Oct 2011 04:00:00 +0100 5380086 http://www.medworm.com/index.php?rid=5380085&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22012080%26dopt%3DAbstract Authors: Viano DC, Hamberger A, Bolouri H, Säljö A Abstract Three animal models were evaluated in this study involving head impacts of the rat, including the Marmarou drop-weight and two momentum-exchange techniques. In series 1, 36 Wistar rats were hit on the side of the free-moving head using Marmarou's 450 g impact mass at 4.4, 5.4, and 6.3 m/s. Head acceleration was measured and injuries were observed. The 6.3-m/s side impact resulted in no deaths, no skull fractures, infrequent contusions, and some injuries consistent with diffuse axonal injury. In series 2, 57 Marmarou drop-weight tests were conducted to study head biomechanical responses. Marmarou's technique involves a head impact followed by prolonged loading into a foam pad under the animal. Based on the literature, t... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380085 Thu, 20 Oct 2011 04:00:00 +0100 5380085 http://www.medworm.com/index.php?rid=5380084&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22012081%26dopt%3DAbstract The objective of this study is to characterize the rotational kinematics of the head associated with concussive impacts using a large head acceleration dataset collected from human subjects. The helmets of 335 football players were instrumented with accelerometer arrays that measured head acceleration following head impacts sustained during play, resulting in data for 300,977 sub-concussive and 57 concussive head impacts. The average sub-concussive impact had a rotational acceleration of 1230 rad/s(2) and a rotational velocity of 5.5 rad/s, while the average concussive impact had a rotational acceleration of 5022 rad/s(2) and a rotational velocity of 22.3 rad/s. An injury risk curve was developed and a nominal injury value of 6383 rad/s(2) associated with 28.3 rad/s represents 50% ri... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380084 Thu, 20 Oct 2011 04:00:00 +0100 5380084 http://www.medworm.com/index.php?rid=5380083&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22012082%26dopt%3DAbstract In this study, we used microindentation to determine viscoelastic properties of different anatomical structures in sagittal slices of juvenile and adult rat brain. We find that the rat brain is spatially heterogeneous in this anatomical plane supporting previous results in the coronal plane. In addition, the brain becomes stiffer and more heterogeneous as the animal matures. This dynamic, region-specific data will support the development of more biofidelic computational models of brain injury biomechanics and the testing of hypotheses about the manner in which different anatomical structures are injured in a head impact. PMID: 22012082 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380083 Thu, 20 Oct 2011 04:00:00 +0100 5380083 http://www.medworm.com/index.php?rid=5380082&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22012083%26dopt%3DAbstract Authors: Mihalik JP, Guskiewicz KM, Marshall SW, Blackburn JT, Cantu RC, Greenwald RM Abstract The age at which young hockey players should safely body check is unknown. We sought to determine if playing position (defensemen vs. forwards), event type (practice vs. game), or head impact location (top vs. back vs. front vs. sides) had an effect on head impact biomechanics in youth hockey. A total of 52 Bantam (13-14 years old) and Midget (15-16 years old) ice hockey players wore accelerometer-instrumented helmets for two seasons. Biomechanical data were captured for 12,253 head impacts during 151 games and 137 practices. Random intercepts general mixed linear models were employed to analyze differences in linear acceleration, rotational acceleration, and HITsp by player position, e... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380082 Thu, 20 Oct 2011 04:00:00 +0100 5380082 http://www.medworm.com/index.php?rid=5380081&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22012084%26dopt%3DAbstract The objective of this study was to evaluate the response of catcher and umpire masks to impacts at these different regions to discover the impact conditions that represent the greatest risk of injury. A series of 10 events in which a catcher or umpire in Major League Baseball, who experienced a foul ball to the mask that resulted in a concussion, were analyzed through video and data on pitch characteristics. It was found that the impacts were distributed across the face, and the median plate speed was approximately 38 m/s (84 mph). To determine the relative severity of each identified impact location, an instrumented Hybrid III head outfitted with a catcher or umpire mask was impacted with baseballs. Testing at 27 and 38 m/s (60 and 84 mph) suggested that impacts to the center-eyebrow ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380081 Thu, 20 Oct 2011 04:00:00 +0100 5380081 http://www.medworm.com/index.php?rid=5380080&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22012085%26dopt%3DAbstract Authors: Bass CR, Panzer MB, Rafaels KA, Wood G, Shridharani J, Capehart B Abstract Traumatic brain injury (TBI) from blast produces a number of conundrums. This review focuses on five fundamental questions including: (1) What are the physical correlates for blast TBI in humans? (2) Why is there limited evidence of traditional pulmonary injury from blast in current military field epidemiology? (3) What are the primary blast brain injury mechanisms in humans? (4) If TBI can present with clinical symptoms similar to those of Post-Traumatic Stress Disorder (PTSD), how do we clinically differentiate blast TBI from PTSD and other psychiatric conditions? (5) How do we scale experimental animal models to human response? The preponderance of the evidence from a combination of clinical prac... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380080 Thu, 20 Oct 2011 04:00:00 +0100 5380080 http://www.medworm.com/index.php?rid=5380079&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22012086%26dopt%3DAbstract This article provides a review of the literature for computer vision and image understanding techniques applied to MAS images. The focus of this article is to elucidate a perspective on how computer vision techniques can be used to support and enhance the capabilities of biophotonic imaging modalities during surgery. Note that while MAS encompasses a variety of surgical specializations this review does not involve procedures performed in the interventional suite. The review has been carried out based on searches in the PubMed and IEEE databases using the article's keywords. PMID: 22012086 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380079 Thu, 20 Oct 2011 04:00:00 +0100 5380079 http://www.medworm.com/index.php?rid=5380078&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22012087%26dopt%3DAbstract This article introduces electrocardiographic (ECG) parameters for artificially induced hypoglycemia detection. In addition, a hybrid technique of swarm-based support vector machine (SVM) is introduced for hypoglycemia detection using the ECG parameters as inputs. In this technique, a particle swarm optimization (PSO) is proposed to optimize the SVM to detect hypoglycemia. In an experiment using medical data of patients with Type 1 diabetes, the introduced ECG parameters show significant contributions to the performance of the hypoglycemia detection and the proposed detection technique performs well in terms of sensitivity and specificity. PMID: 22012087 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380078 Thu, 20 Oct 2011 04:00:00 +0100 5380078 http://www.medworm.com/index.php?rid=5380095&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22006428%26dopt%3DAbstract This study investigates the use of features extracted from intramuscular electromyography (EMG) for estimating grasping force in the ipsilateral and contralateral (mirrored) hand, during bilateral grasping tasks. This is relevant since force estimation using mirror tasks is a potentially useful pathway for the clinical training of unilateral amputees. Bilateral grasping force and intramuscular EMG (wire electrodes) of the right forearm were measured in 10 able-bodied subjects. The features extracted from the EMG signal were the root mean square, the global discharge rate, the standard sample entropy, and the constraint sample entropy (CSE). The association between the EMG features and force was modeled using a first-order polynomial model, a second-order exponential model, and an artificia... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380095 Wed, 19 Oct 2011 04:00:00 +0100 5380095 http://www.medworm.com/index.php?rid=5380094&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22009311%26dopt%3DAbstract Authors: Curry FE, Adamson RH Abstract Endothelial cells are covered with a polysaccharide rich layer more than 400 nm thick, mechanical properties of which limit access of circulating plasma components to endothelial cell membranes. The barrier properties of this endothelial surface layer are deduced from the rate of tracer penetration into the layer and the mechanics of red and white cell movement through capillary microvessels. This review compares the mechanosensor and permeability properties of an inner layer (100-150 nm, close to the endothelial membrane) characterized as a quasi-periodic structure which accounts for key aspects of transvascular exchange and vascular permeability with those of the whole endothelial surface layers. We conclude that many of the barrier proper... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380094 Wed, 19 Oct 2011 04:00:00 +0100 5380094 http://www.medworm.com/index.php?rid=5380093&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22009312%26dopt%3DAbstract Authors: Subotić M, Sarić Z, Jovičić ST Abstract Transient otoacoustic emission (TEOAE) is a method widely used in clinical practice for assessment of hearing quality. The main problem in TEOAE detection is its much lower level than the level of environmental and biological noise. While the environmental noise level can be controlled, the biological noise can be only reduced by appropriate signal processing. This paper presents a new two-probe preprocessing TEOAE system for suppression of the biological noise by adaptive filtering. The system records biological noises in both ears and applies a specific adaptive filtering approach for suppression of biological noise in the ear canal with TEOAE. The adaptive filtering approach includes robust sign error LMS algorithm, stimuli re... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380093 Wed, 19 Oct 2011 04:00:00 +0100 5380093 http://www.medworm.com/index.php?rid=5380092&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22009313%26dopt%3DAbstract In conclusion, we demonstrate that in subject-specific computational hemodynamics models of the human aorta the imposition of BC settings based on non-invasively measured flow rate waveforms influences indicators of abnormal flow to a large extent. Hence, a BCs set-up assuring realistic, subject-specific instantaneous flow rate distribution must be applied when BCs such as flow rates are prescribed. PMID: 22009313 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380092 Wed, 19 Oct 2011 04:00:00 +0100 5380092 http://www.medworm.com/index.php?rid=5380091&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22009314%26dopt%3DAbstract The objective of this study was to assess the effect of high concentrations of magnesium ions on the matrix production of goat costal fibrochondrocytes in vitro. Cells were cultured using a scaffoldless approach with media containing magnesium chloride (MgCl(2)) or magnesium sulfate (MgSO(4)) at concentrations of 20, 50, and 100 mM in addition to the baseline magnesium concentration of 0.8 mM MgSO(4). At 4 weeks, there were no significant differences in compressive tangent modulus and total matrix production between constructs cultured in 20 mM Mg(2+) and the 0.8 mM Mg(2+) control (435 ± 47 kPa). There was a significant decrease in compressive tangent modulus compared to the 0.8 mM Mg(2+) constructs in the 50 mM MgCl(2) and MgSO(4) groups, while the 100 mM groups were not me... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380091 Wed, 19 Oct 2011 04:00:00 +0100 5380091 http://www.medworm.com/index.php?rid=5380090&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22009315%26dopt%3DAbstract This study describes the effect of zinc on monocyte adhesion to endothelial cells under different shear stress regimens, which may trigger atherogenesis. Human umbilical vein endothelial cells were exposed to steady shear stress (15 dynes/cm(2) or 1 dyne/cm(2)) or reversing shear stress (time average 1 dyne/cm(2)) for 24 h. In all shear stress regimes, zinc deficiency enhanced THP-1 cell adhesion, while heparinase III reduced monocyte adhesion following reversing shear stress exposure. Unlike other shear stress regimes, reversing shear stress alone enhanced monocyte adhesion, which may be associated with increased H(2)O(2) and superoxide together with relatively low levels of nitric oxide (NO) production. L-N(G)-Nitroarginine methyl ester (L-NAME) treatment increased monocyte adhesion und... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380090 Wed, 19 Oct 2011 04:00:00 +0100 5380090 http://www.medworm.com/index.php?rid=5380089&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22009316%26dopt%3DAbstract This study sought to reduce TAL impedance using computational fluid dynamics (CFD). CFD was performed on TAL models with inlet and outlet expansion and contraction angles, θ, of 15°, 45°, and 90°. Pulsatile blood flow was simulated for flow rates of 2-6 L/min, heart rates of 80 and 100 beats/min, and inlet pulsatilities of 3.75 and 2. Pressure and flow data were used to calculate the zeroth and first harmonic impedance moduli, Z (0) and Z (1), respectively. The 45° and 90° models were also tested in vitro under similar conditions. CFD results indicate Z (0) increases as stroke volume and θ increase. At 4 L/min, 100 beats/min, and a pulsatility of 3.75, Z (0) was 0.47, 0.61, and 0.79 mmHg/(L/min) for the 15°, 45°, and 90° devices, respect... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380089 Wed, 19 Oct 2011 04:00:00 +0100 5380089 http://www.medworm.com/index.php?rid=5380088&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22009317%26dopt%3DAbstract Authors: Cornelissen CG, Dietrich M, Krüger S, Spillner J, Schmitz-Rode T, Jockenhoevel S Abstract Fibrin gel has proven a valuable scaffold for tissue engineering. Complex geometries can be produced by injection molding; it offers effective cell seeding and can be produced autologous. In order to evaluate its suitability for respiratory tissue engineering, we examined proliferation, functionality, and differentiation of respiratory epithelial cells on fibrin gel in comparison to culture on collagen-coated, microporous membranes. Respiratory epithelial cells formed a confluent layer by day 4, and proliferation showed no significant difference with respect to surface. Measurement of the transepithelial electrical resistance reflected the development of a confluent epithelial cell l... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380088 Wed, 19 Oct 2011 04:00:00 +0100 5380088 http://www.medworm.com/index.php?rid=5380087&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22009318%26dopt%3DAbstract Authors: Foley CP, Nishimura N, Neeves KB, Schaffer CB, Olbricht WL Abstract Convection-enhanced delivery (CED) is a promising technique for administering large therapeutics that do not readily cross the blood brain barrier to neural tissue. It is of vital importance to understand how large drug constructs move through neural tissue during CED to optimize construct and delivery parameters so that drugs are concentrated in the targeted tissue, with minimal leakage outside the targeted zone. Experiments have shown that liposomes, viral vectors, high molecular weight tracers, and nanoparticles infused into neural tissue localize in the perivascular spaces of blood vessels within the brain parenchyma. In this work, we used two-photon excited fluorescence microscopy to monitor the real-... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380087 Wed, 19 Oct 2011 04:00:00 +0100 5380087 http://www.medworm.com/index.php?rid=5380096&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22006427%26dopt%3DAbstract We present an overview of two acousto-optic sensing approaches. In the first, we demonstrate that the local transport mean free path within turbid media can be obtained by varying the pressure of the ultrasound field and processing the resulting acousto-optic signals. In the second, we demonstrate that the acousto-optic response elicited by a high-intensity ultrasound field during thermal therapy can be used to monitor the onset of lesion formation, ascertain lesion volume, and provide real-time control of exposure duration. PMID: 22006427 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380096 Tue, 18 Oct 2011 04:00:00 +0100 5380096 http://www.medworm.com/index.php?rid=5380098&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21997391%26dopt%3DAbstract We present a robust and reproducible glass microfluidic system, for the maintenance and "interrogation" of head and neck squamous cell carcinoma (HNSCC) tumor biopsies, which enables continuous media perfusion and waste removal, recreating in vivo laminar flow and diffusion-driven conditions. Primary HNSCC or metastatic lymph samples were subsequently treated with 5-fluorouracil and cisplatin, alone and in combination, and were monitored for viability and apoptotic biomarker release 'off-chip' over 7 days. The concentration of lactate dehydrogenase was initially high but rapidly dropped to minimally detectable levels in all tumor samples; conversely, effluent concentration of WST-1 (cell proliferation) increased over 7 days: both factors demonstrating cell viability. Addition of cell lys... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380098 Sat, 15 Oct 2011 04:00:00 +0100 5380098 http://www.medworm.com/index.php?rid=5380097&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22002836%26dopt%3DAbstract Authors: Law JK, Yeung CK, Li L, Rudd JA, Ingebrandt S, Chan M Abstract The microelectrode array (MEA) can be used to study extracellular field potentials (exFPs) of electrogenic cells. Microcontact printing, which must be repeated after each experiment, is often used to promote accurate positioning of cells onto electrodes. The present study used MEAs with evenly spaced detection electrodes aligning along permanent SU-8 topographical guidance channels to measure propagation direction and speed. Chronotropic agents, isoproterenol (ISO, 1 nM-1 mM), and verapamil (VP, 1 nM-10 μM); and potassium channel openers (KCOs), pinacidil (PIN), and SDZ PCO400 (SDZ), were used to characterize these MEA chips. ISO (1 mM) enhanced the propagation speed from 247.25 ± 50.58 μm/ms 381.29�... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380097 Sat, 15 Oct 2011 04:00:00 +0100 5380097 http://www.medworm.com/index.php?rid=5380099&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21997390%26dopt%3DAbstract This article will be helpful in developing a generalized systematic approach to concussion management and highlight specific RTP guidelines. The article will also touch upon specific contraindications to RTP, the role of neuropsychological testing in RTP, and other considerations and complications that affect an athlete's ability to return to competition. Finally, considerations for terminating an athlete's competitive season or ending a career after sustaining a concussion resulting in prolonged and protracted symptomatology or repeated concussions will be reviewed. PubMed and Google were searched using the key terms mentioned below. In addition, the author's library of concussion-related articles was reviewed for the relevant literature. PMID: 21997390 [PubMed - as supplied by publis... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380099 Fri, 14 Oct 2011 04:00:00 +0100 5380099 http://www.medworm.com/index.php?rid=5380114&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21994055%26dopt%3DAbstract Authors: Viano DC, Withnall C, Wonnacott M Abstract An instrumented Hybrid III head was placed in a Schutt ION 4D football helmet and dropped on different turfs to study field types and temperature on head responses. The head was dropped 0.91 and 1.83 m giving impacts of 4.2 and 6.0 m/s on nine different football fields (natural, Astroplay, Fieldturf, or Gameday turfs) at turf temperatures of -2.7 to 23.9 °C. Six repeat tests were conducted for each surface at 0.3 m (1') intervals. The Hybrid III was instrumented with triaxial accelerometers to determine head responses for the different playing surfaces. For the 0.91-m drops, peak head acceleration varied from 63.3 to 117.1 g and HIC(15) from 195 to 478 with the different playing surfaces. The lowest response was with Astropl... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380114 Thu, 13 Oct 2011 04:00:00 +0100 5380114 http://www.medworm.com/index.php?rid=5380113&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21994056%26dopt%3DAbstract Authors: Patel TP, Ventre SC, Meaney DF Abstract Despite its enormous incidence, mild traumatic brain injury is not well understood. One aspect that needs more definition is how the mechanical energy during injury affects neural circuit function. Recent developments in cellular imaging probes provide an opportunity to assess the dynamic state of neural networks with single-cell resolution. In this article, we developed imaging methods to assess the state of dissociated cortical networks exposed to mild injury. We estimated the imaging conditions needed to achieve accurate measures of network properties, and applied these methodologies to evaluate if mild mechanical injury to cortical neurons produces graded changes to either spontaneous network activity or altered network topology.... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380113 Thu, 13 Oct 2011 04:00:00 +0100 5380113 http://www.medworm.com/index.php?rid=5380112&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21994057%26dopt%3DAbstract Authors: Viano DC, Halstead D Abstract Linear impactor tests were conducted on football helmets from the 1970s-1980s to complement recently reported tests on 1990s and 2010s helmets. Helmets were placed on the Hybrid III head with an array of accelerometers to determine translational and rotational acceleration. Impacts were at four sites on the helmet shell at 3.6-11.2 m/s. The four generations of helmets show a continuous improvement in response from bare head impacts in terms of Head Injury Criterion (HIC), peak head acceleration and peak rotational acceleration. Helmets of 2010s weigh 1.95 ± 0.2 kg and are 2.7 times heavier than 1970s designs. They are also 4.3 cm longer, 7.6 cm higher, and 4.9 cm wider. The extra size and weight allow the use of energy absorbing padding th... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380112 Thu, 13 Oct 2011 04:00:00 +0100 5380112 http://www.medworm.com/index.php?rid=5380111&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21994058%26dopt%3DAbstract Authors: Broglio SP, Surma T, Ashton-Miller JA Abstract Researchers are striving to understand the biomechanics of concussive injury that occur in the context of sport by using a number of methodologies. Animal models, video reconstruction, and helmet-based accelerometers have all been used, but have their limitations. The Head Impact Telemetry (HIT) System permits the real-time in vivo tracking of all impacts that occur on the football field and has been used in both the high school and collegiate setting. This review provides a theoretical discussion of concussion mechanics and examines the current literature on the effects of the number of impacts, impact magnitude, impact distribution, and concussion threshold in high school and collegiate football athletes recorded by the HIT ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380111 Thu, 13 Oct 2011 04:00:00 +0100 5380111 http://www.medworm.com/index.php?rid=5380110&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21994059%26dopt%3DAbstract Authors: Viano DC, Withnall C, Wonnacott M Abstract The potential for mouthguards to change the risk of concussion was studied in football helmet impacts. The Hybrid III head was modified with an articulating mandible, dentition, and compliant temporomandibular joints (TMJ). It was instrumented for triaxial head acceleration and triaxial force at the TMJs and upper dentition. Mandible force and displacement were validated against cadaver impacts to the chin. In phase 1, one of five mouthguards significantly lowered HIC in 6.7 m/s impacts (p = 0.025) from the no mouthguard condition but not in 9.5 m/s tests. In phase 2, eight mouthguards increased HIC from +1 to +17% in facemask impacts that loaded the chinstraps and mandible; one was statistically higher (p = 0.018). Peak hea... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380110 Thu, 13 Oct 2011 04:00:00 +0100 5380110 http://www.medworm.com/index.php?rid=5380109&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21994060%26dopt%3DAbstract In this study, data from 37,128 head impacts collected at Virginia Tech during games from 2006 to 2010 were analyzed. Peak head acceleration exceeded 100 g in 516 impacts, and the Head Injury Criterion (HIC) exceeded 200 in 468 impacts. Four instrumented players in the dataset sustained a concussion. These data were used to develop risk curves for concussion as a function of peak head acceleration and HIC. The validity of this biomechanical approach was assessed using epidemiological data on concussion incidence from other sources. Two specific aspects of concussion incidence were addressed: the variation by player position, and the frequency of repeat concussions. The HIT System data indicated that linemen sustained the highest overall number of head impacts, while skill positions sustai... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380109 Thu, 13 Oct 2011 04:00:00 +0100 5380109 http://www.medworm.com/index.php?rid=5380108&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21994061%26dopt%3DAbstract Authors: Ocwieja KE, Mihalik JP, Marshall SW, Schmidt JD, Trulock SC, Guskiewicz KM Abstract Football accounts for 55% of concussions to collegiate athletes. In the National Football League, players are at a greater risk for concussion during kickoffs and punts compared to rushing and passing plays. The two primary purposes of this study were to determine if game-related special teams head impacts were greater in magnitude than head impacts sustained during offensive and defensive plays, and to better understand the effect closing distance between players (short vs. long) had on head impact magnitude. Collegiate football players were enrolled in a prospective cohort study assessing head impact biomechanics during special teams, offensive, and defensive collisions; long closing dist... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380108 Thu, 13 Oct 2011 04:00:00 +0100 5380108 http://www.medworm.com/index.php?rid=5380107&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21994062%26dopt%3DAbstract This article reports an approach to and preliminary results from the correlation of subject-specific FE model-predicted regions of high strain associated with diagnosed concussion and diffusion tensor imaging to assess changes in white matter integrity in the corpus callosum (CC). Ten football and ice hockey players who wore instrumented helmets to record head impacts sustained during play completed high field magnetic resonance imaging preseason and within 10 days of a diagnosed concussion. The Dartmouth Subject-Specific FE Head model was used to generate regional predictions of strain and strain rate following each impact associated with concussion. Maps of change in fractional anisotropy (FA) and median diffusivity (MD) were generated for the CC of each athlete to correlate strain with... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380107 Thu, 13 Oct 2011 04:00:00 +0100 5380107 http://www.medworm.com/index.php?rid=5380105&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21994064%26dopt%3DAbstract Authors: Chu JJ, Beckwith JG, Leonard DS, Paye CM, Greenwald RM Abstract It is estimated that 10-20% of United States soldiers returning from Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) have suffered at least one instance of blast-induced traumatic brain injury (bTBI) with many reporting persistent symptomology and long-term effects. This variation in blast response may be related to the complexity of blast waves and the many mechanisms of injury, including over-pressurization due to the shock wave and potential for blunt impacts to the head from shrapnel or from other indirect impacts (e.g., building, ground, and vehicle). To help differentiate the effects of primary, secondary, and tertiary effects of blast, a custom sensor was developed to simultaneously m... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380105 Thu, 13 Oct 2011 04:00:00 +0100 5380105 http://www.medworm.com/index.php?rid=5380104&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21994065%26dopt%3DAbstract This study proposed two criteria based on angular accelerations for Traumatic Brain Injury (TBI), which we call Rotational Injury Criterion (RIC) and Power Rotational Head Injury Criterion (PRHIC). Concussive and non-concussive head acceleration data obtained from football head impacts were utilized to develop new injury criteria. A well-validated human brain Finite Element (FE) model was employed to find out effective injury criteria for TBI. Correlation analyses were performed between the proposed criteria and FE-based brain injury predictors such as Cumulative Strain Damage Measure (CSDM), which is defined as the percent volume of the brain that exceeds a specified first principal strain threshold, proposed to predict Diffuse Axonal Injury (DAI) which is one of TBI. The RIC was signific... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380104 Thu, 13 Oct 2011 04:00:00 +0100 5380104 http://www.medworm.com/index.php?rid=5380103&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21994066%26dopt%3DAbstract In this study, a rodent model of primary blast neurotrauma was employed to determine the pressure at which acute neurological alterations occurred. Rats were exposed to a single low intensity shock wave at a pressure of 0, 97, 117, or 153 kPa. Following exposure, rats were assessed for acute cognitive alterations using the Morris water maze and motor dysfunction using the horizontal ladder test. Subsequently, histological analyses of three brain regions (primary motor cortex, the hippocampal dentate gyrus region, and the posteromedial cortical amygdala) were conducted. Histological parameters included measuring the levels of glial fibrillary acidic protein (GFAP) to identify astrocyte activation, cleaved caspase-3 for early apoptosis identification and Fluoro-Jade B (FJB) which labels deg... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380103 Thu, 13 Oct 2011 04:00:00 +0100 5380103 http://www.medworm.com/index.php?rid=5380102&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21994067%26dopt%3DAbstract Authors: Gysland SM, Mihalik JP, Register-Mihalik JK, Trulock SC, Shields EW, Guskiewicz KM Abstract Concussions sustained during college and professional football careers have been associated with both acute and chronic neurologic impairment. The contribution of subconcussive impacts to this impairment has not been adequately studied. Therefore, we investigated the relationship between subconcussive impacts and concussion history on clinical measures of neurologic function. Forty-six collegiate football players completed five clinical measures of neurologic function commonly employed in the evaluation of concussion before and after a single season. These tests included the Automated Neuropsychological Assessment Metrics, Sensory Organization Test, Standardized Assessment of Concus... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380102 Thu, 13 Oct 2011 04:00:00 +0100 5380102 http://www.medworm.com/index.php?rid=5380101&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21994068%26dopt%3DAbstract Authors: Beckwith JG, Greenwald RM, Chu JJ Abstract Over the last decade, advances in technology have enabled researchers to evaluate concussion biomechanics through measurement of head impacts sustained during play using two primary methods: (1) laboratory reconstruction of open-field head contact, and (2) instrumented helmets. The purpose of this study was to correlate measures of head kinematics recorded by the Head Impact Telemetry (HIT) System (Simbex, NH) with those obtained from a Hybrid III (HIII) anthropometric headform under conditions that mimicked impacts occurring in the NFL. Linear regression analysis was performed to correlate peak linear acceleration, peak rotational acceleration, Gadd Severity Index (GSI), and Head Injury Criterion (HIC(15)) obtained from the instr... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380101 Thu, 13 Oct 2011 04:00:00 +0100 5380101 http://www.medworm.com/index.php?rid=5380100&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21994069%26dopt%3DAbstract Authors: Jabbour JM, Saldua MA, Bixler JN, Maitland KC Abstract Advances in fiber optic technology and miniaturized optics and mechanics have propelled confocal endomicroscopy into the clinical realm. This high resolution, non-invasive imaging technology provides the ability to microscopically evaluate cellular and sub-cellular features in tissue in vivo by optical sectioning. Because many cancers originate in epithelial tissues accessible by endoscopes, confocal endomicroscopy has been explored to detect regions of possible neoplasia at an earlier stage by imaging morphological features in vivo that are significant in histopathologic evaluation. This technique allows real-time assessment of tissue which may improve diagnostic yield by guiding biopsy. Research and development conti... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380100 Thu, 13 Oct 2011 04:00:00 +0100 5380100 http://www.medworm.com/index.php?rid=5380117&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21984512%26dopt%3DAbstract Authors: Miao Q, Reeves AP, Patten FW, Seibel EJ Abstract Absorption dyes are widely used in traditional cytology and pathology clinical practice, while fluorophores and nanoparticles are more often used in biologic research. Optical projection tomographic microscopy (OPTM) is a platform technology that can image the same specimen in multiple modes in 3D, providing morphologic and molecular information concurrently and in exact co-registration. The depth-of-field of a high numerical aperture objective is extended by scanning the focal plane through the sample to generate an optical projection image. Samples of cells or tissue are brought into the OPTM instrument through a microcapillary tube filled with optical index-matching gel. Multiple optical projection images are taken from d... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380117 Sat, 08 Oct 2011 04:00:00 +0100 5380117 http://www.medworm.com/index.php?rid=5380115&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21984514%26dopt%3DAbstract Authors: Lipowsky HH Abstract The endothelial cell (EC) surface is coated with a layer of polysaccharides linked to membrane-bound and trans-membrane proteoglycans that comprise the glycocalyx, which is augmented by adsorbed proteins derived from the blood stream. This surface layer has been shown to affect hemodynamics in small blood vessels of the microcirculation, the resistance to flow, and leukocyte (WBC) to EC adhesion. Parallel studies of WBC-EC adhesion in response to chemoattractants and cytokines, and shedding of constituents of the glycocalyx, have suggested a role for activation of extracellular proteases in mediating the dynamics of WBC adhesion in response to inflammatory and ischemic stimuli. Likely candidates among the many proteases present are the matrix metallopr... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5380115 Sat, 08 Oct 2011 04:00:00 +0100 5380115 http://www.medworm.com/index.php?rid=5297910&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21979168%26dopt%3DAbstract Authors: Madsen SJ, Baek SK, Makkouk AR, Krasieva T, Hirschberg H Abstract Site-specific delivery of nanoparticles poses a significant challenge, especially in the brain where the blood-brain barrier prevents the entry of most therapeutic compounds including nanoparticle-based anti-cancer agents. In this context, the use of macrophages as vectors for the delivery of gold-silica nanoshells to infiltrating gliomas will be reviewed in this article. Gold-silica nanoshells are readily phagocytosed by macrophages without any apparent toxic effects, and the results of in vitro studies have demonstrated the migratory potential of nanoshell-loaded macrophages in human glioma spheroids. Of particular interest is the observation that, after near-infrared exposure of spheroids containing nanos... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5297910 Fri, 07 Oct 2011 04:00:00 +0100 5297910 http://www.medworm.com/index.php?rid=5297909&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21979169%26dopt%3DAbstract Authors: Slomka N, Gefen A Abstract Deep tissue injury (DTI) is a life-threatening type of pressure ulcer which initiates subdermally with muscle necrosis at weight-bearing anatomical locations, where localized elevated tissue strains exist. Though it has been suggested that excessive sustained soft tissue strains might compromise cell viability, which then initiates the DTI, there is no experimental evidence to describe how specifically such a process might take place. Here, we experimentally test the hypothesis that macroscopic tissue deformations translated to cell-level deformations and in particular, to localized tensile strains in the plasma membrane (PM) of cells, increase the permeability of the PM which could disrupt vital transport processes. In order to determine whether... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5297909 Fri, 07 Oct 2011 04:00:00 +0100 5297909 http://www.medworm.com/index.php?rid=5297913&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21971964%26dopt%3DAbstract Authors: Fantini S, Sassaroli A Abstract Optical methods to detect breast cancer on the basis of its increased opacity have been explored for some time. These methods have matured to a point in which they are capable of quantifying the optical properties of breast tissue and translating them into measures of concentrations of relevant tissue components. In particular, near-infrared spectroscopy has been employed to determine the concentrations of hemoglobin, water, and lipids, as well as oxygen saturation of hemoglobin and optical scattering properties in normal and cancerous breast tissue. Dynamic optical measurements can also identify abnormal hemodynamic patterns associated with breast cancer. We review, in this article, a number of results in the field, which show that cancerou... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5297913 Wed, 05 Oct 2011 04:00:00 +0100 5297913 http://www.medworm.com/index.php?rid=5297912&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21971965%26dopt%3DAbstract In this study, we utilize femtosecond laser ablation to produce microchannels inside electrospun polycaprolactone (PCL) scaffolds. These microchannels potentially provide spatially controlled cell distributions approaching those observed in vivo. The ability of such laser-ablated microchannels to direct cell seeding was evaluated. The dimensions chosen were 100 μm wide, 100 μm deep and 10 mm long. Femtosecond laser ablation successfully produced these microchannels in the scaffolds without substantially altering the ~900 nm diameter fibers. Flow within these microchannels was studied by injecting fluorescent polystyrene bead solutions. Direct measurement of bead motion yielded an inlet velocity of 2.78 cm s(-1). This was used for modeling two-dimensional (2D) flow using computation... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5297912 Wed, 05 Oct 2011 04:00:00 +0100 5297912 http://www.medworm.com/index.php?rid=5297911&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21971966%26dopt%3DAbstract This study investigated the biofidelity of this contact by evaluating the impact response of both the chin and manubrium of adult post-mortem human subjects (PMHSs). The adult PMHS data were scaled to a 10-year-old (YO) human size and then compared with the Hybrid III 10YO child (HIII-10C) ATD response with the same test configurations. For both the chin and manubrium, the responses of the scaled PMHS had different characteristics than the HIII-10C ATD responses. Elevated energy impact tests to the PMHS mandible provided a mean injury tolerance value for chin impact force. Chin contact forces in the HIII-10C ATD were calculated in previously conducted HYGE sled crash simulation tests, and these contact forces were strongly correlated with the Head Injury Criterion (HIC(36 ms)). The mean i... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5297911 Wed, 05 Oct 2011 04:00:00 +0100 5297911 http://www.medworm.com/index.php?rid=5297914&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21969108%26dopt%3DAbstract Authors: Gómez C, Olde Dubbelink KT, Stam CJ, Abásolo D, Berendse HW, Hornero R Abstract The aim of the present study was to analyze resting-state brain activity in patients with Parkinson's disease (PD), a degenerative disorder of the nervous system. Magnetoencephalography (MEG) signals were recorded with a 151-channel whole-head radial gradiometer MEG system in 18 early-stage untreated PD patients and 20 age-matched control subjects. Artifact-free epochs of 4 s (1250 samples) were analyzed with Lempel-Ziv complexity (LZC), applying two- and three-symbol sequence conversion methods. The results showed that MEG signals from PD patients are less complex than control subjects' recordings. We found significant group differences (p-values <0.01) for the 10 major cortical areas an... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5297914 Tue, 04 Oct 2011 04:00:00 +0100 5297914 http://www.medworm.com/index.php?rid=5281402&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21947736%26dopt%3DAbstract In this study, a statistical model of cranium geometry for 0- to 3-month-old children was developed by analyzing 11 CT scans using a combination of principal component analysis and multivariate regression analysis. Radial basis function was used to morph the geometry of a baseline child head finite element (FE) model into models with geometries representing a newborn, a 1.5-month-old, and a 3-month-old infant head. These three FE models were used in a parametric study of near-vertex impact conditions to quantify the sensitivity of different material parameters. Finally, model validation was conducted against peak head accelerations in cadaver tests under different impact conditions, and optimization techniques were used to determine the material properties. The results showed that the stat... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5281402 Sat, 24 Sep 2011 04:00:00 +0100 5281402 http://www.medworm.com/index.php?rid=5247336&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21938555%26dopt%3DAbstract Authors: Nakamura T, Fujihara S, Yamamoto-Nagata K, Katsura T, Inubushi T, Tanaka E Abstract The purpose of this study was to examine the effect of low-intensity pulsed ultrasound (LIPUS) on the cell proliferation and growth of synovial membrane cells stimulated with inflammatory cytokines, and to evaluate the effectiveness of LIPUS treatment of synovitis in the knee joints of animal models for rheumatoid arthritis. The rabbit knee synovial membrane cell line, HIG-82, was cultured in medium with or without IL-1β or TNF-α. Four hours after stimulation with the cytokines, the cells received LIPUS or sham exposure. Cell proliferation and growth were then analyzed. Using MRL/lpr mice, the anti-inflammatory effects of LIPUS were also evaluated in vivo. Stimulation with proinflammatory... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5247336 Thu, 22 Sep 2011 04:00:00 +0100 5247336 http://www.medworm.com/index.php?rid=5247338&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21932167%26dopt%3DAbstract In this study, we aimed to achieve and enhance redifferentiation of dedifferentiated chondrocytes with dual genes of transforming growth factor (TGF)-β3 and short hairpin RNA (shRNA) that restore chondrocytic phenotype and silence fibrous collagen type I (Col I), respectively. It was hypothesized that gene delivery of the two targets would promote chondrogenesis in chondrocytes, and meanwhile inhibit the expression of the undesired Col I. Three types of recombinant adenoviruses were constructed. Two of them were of single-function vectors with the ability to express either TGF-β3 (Ad-TGFβ3) or shRNA (specific for Col I, Ad-shRNA); the third type was of double-function vectors that encode both TGF-β3 and anti-Col I shRNA (Ad-double). We infected the dedifferentiated chondrocytes with Ad... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5247338 Tue, 20 Sep 2011 04:00:00 +0100 5247338 http://www.medworm.com/index.php?rid=5247337&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21932168%26dopt%3DAbstract This article proposed a method to track the changes in health condition of a patient after coronary stenting over seven successive seasons based on daily pulse rate (PR). The pulse signal was recorded by an unconstrained monitoring system during sleep. Seasonal PR dynamics were evaluated by both linear measures, including time domain and frequency domain indexes, and nonlinear measures such as noise limit (NL), detection rate (DR), sample entropy (SampEn), and Poincaré plots. NL and DR were derived using the noise titration method. Significant changes in seasonal indexes of the patient were evaluated statistically. The results show that an overall downward trend of the PR dynamics corresponds to changes in the patient's health condition that began in winter and developed in spring and wor... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5247337 Tue, 20 Sep 2011 04:00:00 +0100 5247337 http://www.medworm.com/index.php?rid=5219245&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21909817%26dopt%3DAbstract Authors: Vanden Berg-Foels WS, Schwager SJ, Todhunter RJ, Reeves AP Abstract Developmental dysplasia of the hip (DDH) is a common cause of elevated contact stress and early onset osteoarthritis (OA). We hypothesized that adaptation to focal loading during postnatal development would result in signature changes to the shape of the femoral head secondary center of ossification (SCO). SCO shape was evaluated in a canine model of DDH at ages 14 and 32 weeks. The evolving 3D morphology of the SCO was captured using serial quantitative computed tomography. A discrete medial representation shape model was fit to each SCO and served as the basis for quantitative thickness and bending measurements. Shape measurements were tested for associations with hip subluxation and degeneration. At 32... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5219245 Sat, 10 Sep 2011 04:00:00 +0100 5219245 http://www.medworm.com/index.php?rid=5219244&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21909818%26dopt%3DAbstract Authors: Swenson DJ, Geneser SE, Stinstra JG, Kirby RM, Macleod RS Abstract The electrocardiogram (ECG) is ubiquitously employed as a diagnostic and monitoring tool for patients experiencing cardiac distress and/or disease. It is widely known that changes in heart position resulting from, for example, posture of the patient (sitting, standing, lying) and respiration significantly affect the body-surface potentials; however, few studies have quantitatively and systematically evaluated the effects of heart displacement on the ECG. The goal of this study was to evaluate the impact of positional changes of the heart on the ECG in the specific clinical setting of myocardial ischemia. To carry out the necessary comprehensive sensitivity analysis, we applied a relatively novel and highly ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5219244 Sat, 10 Sep 2011 04:00:00 +0100 5219244 http://www.medworm.com/index.php?rid=5219246&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21904797%26dopt%3DAbstract The objective of this study was to evaluate the use of electric impedance spectroscopy (EIS) to follow the maturation and development of barrier function in human embryonic stem cell-derived RPE (hESC-RPE). Barrier function was assessed using EIS, permeability measurements, and microscopic inspection in intact cells and following calcium sequestration with ethylene glycol tetraacetic acid (EGTA). The results showed that the cultures with the most mature morphology had the highest impedance and the lowest permeability values. The EIS of samples of high integrity fitted well to the equivalent model of a single RC circuit, whereas the semicircular shape of the Nyquist plots was distorted for samples of lower integrity. EGTA treatment resulted in lower impedance values and changes in the shape... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5219246 Fri, 09 Sep 2011 04:00:00 +0100 5219246 http://www.medworm.com/index.php?rid=5219249&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21887588%26dopt%3DAbstract In this study the socket donning procedure is modeled using an explicit finite element method based on the patient-specific geometry obtained from CT and laser scan data. Over stumps the mean maximum pressure is 4 kPa (SD 1.7) and the mean maximum shear stresses are 1.4 kPa (SD 0.6) and 0.6 kPa (SD 0.3) in longitudinal and circumferential directions, respectively. Locations of the maximum values are according to pressure zones at the sockets. The stress-strain states obtained in this study can be considered more reliable than others, since there are normal and tangential stresses associated to the socket donning procedure. PMID: 21887588 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5219249 Fri, 02 Sep 2011 04:00:00 +0100 5219249 http://www.medworm.com/index.php?rid=5219248&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21887589%26dopt%3DAbstract Authors: Choi WI, Sahu A, Kim YH, Tae G Abstract Gold nanorods (GNRs), which strongly absorb near-infrared (NIR) light, have shown great potential in fields of biomedical application. These include photothermal therapy, molecular imaging, biosensing, and gene delivery, especially for the treatment of diseased tissues such as cancer. These biomedical applications of GNRs arise from their various useful properties; photothermal (nanoheater) properties, efficient large scale synthesis, easy functionalization, and colloidal stability. In addition, GNRs do not decompose and have an enhanced scattering signal and tunable longitudinal plasmon absorption which allow them to be used as a stable contrast agent. Therefore, GNRs are also promising theranostic agents, combining both tumor diagn... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5219248 Fri, 02 Sep 2011 04:00:00 +0100 5219248 http://www.medworm.com/index.php?rid=5219247&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21887590%26dopt%3DAbstract Authors: Bishara W, Isikman SO, Ozcan A Abstract Microfluidic devices aim at miniaturizing, automating, and lowering the cost of chemical and biological sample manipulation and detection, hence creating new opportunities for lab-on-a-chip platforms. Recently, optofluidic devices have also emerged where optics is used to enhance the functionality and the performance of microfluidic components in general. Lensfree imaging within microfluidic channels is one such optofluidic platform, and in this article, we focus on the holographic implementation of lensfree optofluidic microscopy and tomography, which might provide a simpler and more powerful solution for three-dimensional (3D) on-chip imaging. This lensfree optofluidic imaging platform utilizes partially coherent digital in-line ho... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5219247 Fri, 02 Sep 2011 04:00:00 +0100 5219247 http://www.medworm.com/index.php?rid=5219250&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21877220%26dopt%3DAbstract Authors: Maheshwari V, Samavedham L, Rangaiah GP Abstract A kinetic model based on first principles, for β(2)-microglobulin, is presented to obtain precise parameter estimates for individual patient. To reduce the model complexity, the number of model parameters was reduced using a priori identifiability analysis. The model validity was confirmed with the clinical data of ten renal patients on post-dilution hemodiafiltration. The model fit resulted in toxin distribution volume (V (d)) of 14.22 ± 0.75 L, plasma fraction in extracellular compartment (f (P)) of 0.39 ± 0.03, and inter-compartmental clearance of 44 ± 4.1 mL min(-1). Parameter estimates suggest that V (d) and f (P) are much higher in hemodialysis patients than in normal subjects. The developed model predicts... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5219250 Tue, 30 Aug 2011 04:00:00 +0100 5219250 http://www.medworm.com/index.php?rid=5176746&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21870248%26dopt%3DAbstract Authors: Qiu J, Wang G, Zheng Y, Hu J, Peng Q, Yin T Abstract Considering that oxidized low-density lipoprotein (ox-LDL) may inhibit endothelial cell (EC) migration and proliferation during endothelialization, we hypothesize that the Id1 protein promotes endothelialization exposed to ox-LDL. Cell proliferation was evaluated by cell counts, and cell migration was evaluated by wound closure assay. The role of Id1 in the cell migration and proliferation was appraised through building Id1 overexpression and silencing ECs. Here, we report that Id1 in human umbilical vascular ECs (HUVECs) was up-regulated by ox-LDL in a dose- and time-dependent manner. Low concentrations of ox-LDL increased the proliferation and migration of EC. High concentrations of ox-LDL suppressed HUVECs proliferati... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5176746 Thu, 25 Aug 2011 23:00:00 +0100 5176746 http://www.medworm.com/index.php?rid=5176745&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21870249%26dopt%3DAbstract This study illustrates that bracing has a significant influence on the biomechanical response of human occupants in frontal sled tests and provides novel biomechanical data that can be used to refine and validate computational models and ATDs used to assess injury risk in automotive collisions. PMID: 21870249 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5176745 Thu, 25 Aug 2011 23:00:00 +0100 5176745 http://www.medworm.com/index.php?rid=5157517&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21863387%26dopt%3DAbstract This article touches on the two main aspects of this research topic: first it introduces a mechanical refinement of a device that can be used to effectively measure finger impedance during manipulation tasks; then, it describes a pilot study aimed at identifying the inertia of the finger and the viscous and elastic properties of finger muscles. The proposed wearable exoskeleton, which has been designed to measure finger posture and impedance modulation while leaving the palm free, is capable of applying fast displacements while monitoring the interaction forces between the human finger and the robotic links. Moreover, due to the relatively small inertia of the fingers, it allows us to meet some stringent specifications, performing relatively large displacements (∼45°) before the stretch... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5157517 Tue, 23 Aug 2011 23:00:00 +0100 5157517 http://www.medworm.com/index.php?rid=5141617&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21847685%26dopt%3DAbstract In this study, we laser ablated electrospun poly(L: -lactic acid) (PLA) scaffolds and assessed the ablation process and cellular interaction by examining human adipose-derived stem cell (hASC) viability and proliferation on laser micro-machined scaffolds. Laser ablated pores of 150, 300, and 600 μm diameter were micro-machined through electrospun PLA scaffolds. Laser ablation parameters were varied and it was determined that the aperture and z-travel direction of the laser linearly correlated with the ablated pore diameter. To assess cytocompatibility of the micro-machined scaffolds, hASCs were seeded on each scaffold and cell viability was assessed on day 7. Human ASCs were able to adhere around the micro-machined features. DNA content was quantified on all scaffolds and it was determin... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5141617 Tue, 16 Aug 2011 23:00:00 +0100 5141617 http://www.medworm.com/index.php?rid=5141618&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21837514%26dopt%3DAbstract In this study, we propose an innovative method for the direct measurement of the peripheral artery elasticity using a spring constant model, based on the arterial pressure wave equation, vibrating in a radial direction. By means of the boundary condition of the pressure wave equation at the maximum peak, we can derive the spring constant used for evaluating peripheral arterial elasticity. The calculated spring constants of six typical subjects show a coincidence with their proper arterial elasticities. Furthermore, the comparison between the spring constant method and pulse wave velocity (PWV) was investigated in 70 subjects (21-64 years, 47 normotensives and 23 hypertensives). The results reveal a significant negative correlation for the spring constant vs. PWV (correlation coefficient ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5141618 Thu, 11 Aug 2011 23:00:00 +0100 5141618 http://www.medworm.com/index.php?rid=5141619&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21833680%26dopt%3DAbstract This article presents a computer-aided detection system for capsule endoscopy (CE) images using contourlet-based color textural features to recognize tumors in the digestive tract. As tumor exhibits rich information in color texture, a novel color texture feature based on contourlet transform is proposed to describe characteristics of tumor in CE images. The proposed features are a hybrid of contourlet transform and uniform local binary pattern, yielding detailed and robust color texture features in multi-directions for CE images. Sequential floating forward search approach is further applied to refine the proposed features. With support vector machine for classification, comprehensive experiments on our present data reveal an encouraging accuracy of 93.6% for tumor detection in CE images ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5141619 Wed, 10 Aug 2011 23:00:00 +0100 5141619 http://www.medworm.com/index.php?rid=5141622&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21822739%26dopt%3DAbstract This study develops and applies a linear, biphasic formulation of hydrogel mechanics that includes a Brinkman term to account for viscous effects. The model is used to predict fluid pressure, relative velocity, and estimated shear stress exerted on cells seeded within a cyclically strained collagen hydrogel with and without imposed cross flow. The model was validated using a confined compression creep test of a cardiac fibroblast-seeded collagen type I hydrogel, and the effect of the added Brinkman term was assessed. The model indicated that the effects of strain and interstitial fluid flow are strongly interdependent in the collagen hydrogel. Our results suggest that the contribution of the Brinkman term is greater in protein hydrogels than in native tissues, and that studies that apply c... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5141622 Fri, 05 Aug 2011 23:00:00 +0100 5141622 http://www.medworm.com/index.php?rid=5141621&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21822740%26dopt%3DAbstract In this study, we extended these approaches toward three-dimensional reconstruction of gap junction distributions based on high-resolution scanning confocal microscopy and image processing. We developed methods for quantitative characterization of gap junction distributions based on analysis of intensity profiles along the principal axes of myocytes. The analyses characterized gap junction polarization at cell ends and higher-order statistical image moments of intensity profiles. The methodology was tested in rat ventricular myocardium. Our analysis yielded novel quantitative data on gap junction distributions. In particular, the analysis demonstrated that the distributions exhibit significant variability with respect to polarization, skewness, and kurtosis. We suggest that this methodolog... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5141621 Fri, 05 Aug 2011 23:00:00 +0100 5141621 http://www.medworm.com/index.php?rid=5141620&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21822741%26dopt%3DAbstract Authors: Almarza AJ, Hagandora CK, Henderson SE Abstract Animal models for temporomandibular joint disorder (TMD) or degradation are necessary for assessing the value of current and future tissue engineering therapies. After reviewing the literature, it is quite apparent that most TMD animal studies can be categorized into chemical approaches or surgical/mechanical approaches. Overall, it was found that the top five cited manuscripts for all chemical models were cited by almost 40% more manuscripts than the top five manuscripts for surgical/mechanical models. It is clear that the chemical approaches have focused on the inflammatory aspect of TMDs and its relationship to pain. However, chemical irritants must be tested in larger animal models, and the effect of short-term inflammati... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5141620 Fri, 05 Aug 2011 23:00:00 +0100 5141620 http://www.medworm.com/index.php?rid=5103974&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21818531%26dopt%3DAbstract Authors: Hettiarachchi HD, Hsu Y, Harris TJ, Penn R, Linninger AA PMID: 21818531 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103974 Thu, 04 Aug 2011 23:00:00 +0100 5103974 http://www.medworm.com/index.php?rid=5103973&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21818532%26dopt%3DAbstract This study aims to present a novel photogrammetry system that can realize simultaneous acquisition of multi-angle head images in a single camera position. Aligning two planar mirrors with the angle of 51.4°, seven views of the head with 25 electrodes are captured simultaneously by the digital camera placed in front of them. A complete set of algorithms for electrode recognition, matching, and 3D reconstruction is developed. It is found that the elapsed time of the whole localization procedure is about 3 min, and camera calibration computation takes about 1 min, after the measurement of calibration points. The positioning accuracy with the maximum error of 1.19 mm is acceptable. Experimental results demonstrate that the proposed system provides a fast and cost-effective method for the E... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103973 Thu, 04 Aug 2011 23:00:00 +0100 5103973 http://www.medworm.com/index.php?rid=5103972&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21818533%26dopt%3DAbstract Authors: Ferl GZ, Wu AM, Distefano JJ PMID: 21818533 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103972 Thu, 04 Aug 2011 23:00:00 +0100 5103972 http://www.medworm.com/index.php?rid=5103971&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21818534%26dopt%3DAbstract This study demonstrates the application of non-destructive image analysis to quantify the positive mechanical effects of combined BP + PDT treatment in the metastatic spine. PMID: 21818534 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103971 Thu, 04 Aug 2011 23:00:00 +0100 5103971 http://www.medworm.com/index.php?rid=5103970&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21818535%26dopt%3DAbstract This study examines (a) the temporal stability of hemodynamic indices of systolic and diastolic function in C57BL/6 mice under 1.5% isoflurane (ISO) (v/v) anesthesia conditions in 50:50 O(2)/N(2)O (v/v) within 90 min post-induction, and (b) the effects of Mn(2+) on the mouse hemodynamic response in male C57BL/6 mice (n = 16). Left ventricular catheterizations allowed estimation of the hemodynamic indices. Hypertonic saline infusion (10%) allowed absolute volume quantification in conjunction with a separate series of aortic flow experiments (n = 3). In a separate cohort of mice (n = 6), MnCl(2) (190 nmoles/g/bw) was infused via the left jugular for 29-39 min, following 11 min of baseline recording, to assess temporal responses. Stable temporal hemodynamic responses were achieved i... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103970 Thu, 04 Aug 2011 23:00:00 +0100 5103970 http://www.medworm.com/index.php?rid=5103975&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21814845%26dopt%3DAbstract Authors: Cerveri P, Marchente M, Chemello C, Confalonieri N, Manzotti A, Baroni G 2D- and 3D-based innovative methods for surgical planning and simulation systems in orthopedic surgery have emerged enabling the interactive or semi-automatic identification of the clinical landmarks (CL) on the patient individual virtual bone anatomy. They enable the determination of the optimal implant sizes and positioning according to the computed CL, the visualization of the virtual bone resections and the simulation of the overall intervention prior to surgery. The virtual palpation of CL, highly dependent upon the examiner's expertise, was proved to be time consuming and to suffer from considerable inter-observer variability. In this article, we propose a fully automatic algorithmic framework that ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103975 Wed, 03 Aug 2011 23:00:00 +0100 5103975 http://www.medworm.com/index.php?rid=5103976&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21811870%26dopt%3DAbstract Authors: Sakamoto N, Kiuchi T, Sato M A coculture of endothelial cells (ECs) and smooth muscle cells (SMCs), which mimics cellular interactions appearing in vivo, has been performed in studies on the relationship between atherogenesis and fluid shear stress conditions. Although healthy arteries in vivo consist of contractile phenotype SMCs, cultured cells used in many studies normally exhibit a synthetic phenotype. Here, we developed an EC-SMC coculture model to investigate the interactions between ECs and contractile SMCs, and examined the effect of shear stress applied to ECs on SMC phenotypes. Cultured human umbilical artery SMCs were differentiated into contractile states by arresting cell growth using a serum-free medium. Western blotting confirmed that SMC expression of contracti... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103976 Tue, 02 Aug 2011 23:00:00 +0100 5103976 http://www.medworm.com/index.php?rid=5103978&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21809144%26dopt%3DAbstract We present here a conceptually new approach to facilitate the coupling of continuum and agent-based models. Because of ubiquitous limitations in both the tissue- and cell-level data from which one derives constitutive relations for continuum models and rule-sets for agent-based models, we suggest that model verification should enforce congruency across scales. That is, multiscale model parameters initially determined from data sets representing different scales should be refined, when possible, to ensure that common outputs are consistent. Potential advantages of this approach are illustrated by comparing simulated aortic responses to a sustained increase in blood pressure predicted by continuum and agent-based models both before and after instituting a genetic algorithm to refine 16 objec... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103978 Mon, 01 Aug 2011 23:00:00 +0100 5103978 http://www.medworm.com/index.php?rid=5103977&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21809145%26dopt%3DAbstract Authors: Chen X, Astary GW, Mareci TH, Sarntinoranont M Direct infusion, or convection-enhanced delivery (CED), into peripheral nerves may provide a method for delivering substances to the intrathecal space or specific fiber bundles entering the spinal cord. To better understand this potential delivery technique, we have characterized the extracellular transport of macromolecular agents from peripheral nerves to the spinal cord in magnetic resonance (MR) imaging studies. High-resolution dynamic contrast-enhanced MR imaging at 11.1 T was used to monitor and characterize in vivo the extracellular transport dynamics of Gd-DTPA-albumin tracer during CED into rat sciatic nerves. Extracellular tracers followed peripheral nerves towards the spinal cord and at vertebral levels L4 and L5 appea... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103977 Mon, 01 Aug 2011 23:00:00 +0100 5103977 http://www.medworm.com/index.php?rid=5103981&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21800202%26dopt%3DAbstract Authors: Liu SJ, Peng KM, Hsiao CY, Liu KS, Chung HT, Chen JK The purpose of this report was to develop novel biodegradable occlusion devices for closure of atrial septal defects (ASD). To manufacture the biodegradable occluders, polycaprolactone (PCL) components were first fabricated by a lab-scale micro-injection molding machine. They were then assembled and hot-spot welded into double umbrella-like devices of 50 mm in diameter. A special mechanism at the axis of the occluder was designed to self-lock the occluder after the two umbrellas were expanded. Furthermore, a nanofibrous matrix of poly-D: -L: -lactide-glycolide (PLGA)/type I collagen blend was produced via electrospinning to develop biodegradable and biomimetic anti-shunt membranes for the occluders. Characterization of the ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103981 Thu, 28 Jul 2011 23:00:00 +0100 5103981 http://www.medworm.com/index.php?rid=5103980&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21800203%26dopt%3DAbstract Authors: Heo SJ, Nerurkar NL, Baker BM, Shin JW, Elliott DM, Mauck RL Because differentiation of mesenchymal stem cells (MSCs) is enacted through the integration of soluble signaling factors and physical cues, including substrate architecture and exogenous mechanical stimulation, it is important to understand how micropatterned biomaterials may be optimized to enhance differentiation for the formation of functional soft tissues. In this work, macroscopic strain applied to MSCs in an aligned nanofibrous microenvironment elicited cellular and nuclear deformations that varied depending on scaffold orientation. Reorientation of aligned, oriented MSCs corresponded at the microscopic scale with the affine approximation of their deformation based on macroscopic strains. Moreover, deformations... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103980 Thu, 28 Jul 2011 23:00:00 +0100 5103980 http://www.medworm.com/index.php?rid=5103979&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21800204%26dopt%3DAbstract Authors: Sakamoto Y, Prudhomme S, Zaman MH Migrating tumor cells can exhibit both mesenchymal- and amoeboid-type behaviors. Recent studies have shown that both cellular and extracellular structural and mechanical variables control the transition of tumor cells from one mode to the other and provide them with morphological plasticity. The mesenchymal-mode migration is characterized by strong adhesion and proteolytic machinery to navigate through complex extracellular matrices. The amoeboid-mode migration is characterized by little or no adhesion and strong actomyosin contraction to squeeze through the matrices. While adhesion dependent migration has been computationally and experimentally studied in both 2D and 3D environments, quantitative models of amoeboid motion in native environmen... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103979 Thu, 28 Jul 2011 23:00:00 +0100 5103979 http://www.medworm.com/index.php?rid=5103984&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21796500%26dopt%3DAbstract This study demonstrates that the glycation model with the same k value might be used in majority of individuals as a tool supporting interpretation of HbA1c in different clinical situations. PMID: 21796500 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103984 Wed, 27 Jul 2011 23:00:00 +0100 5103984 http://www.medworm.com/index.php?rid=5103983&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21796501%26dopt%3DAbstract In this study, a computational model of the wrist joint complex was developed and validated for investigating the biomechanical function of the joint in clinically representative scenarios. Joint behavior and kinematics were dictated only by osteoarticular contact, ligamentous constraints, and muscle loading. Three-dimensional articular surfaces of each bone were generated from CT images, while ligaments and muscles were modeled as linear springs and constant-magnitude force vectors, respectively. Commercially available rigid body dynamics software was to both build the model and simulate joint function. Range of motion model predictions were compared to a cadaveric study analyzing the effects of scaphoid distal pole excision and triquetral excision after radioscapholunate (RSL) fusion for... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103983 Wed, 27 Jul 2011 23:00:00 +0100 5103983 http://www.medworm.com/index.php?rid=5103982&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21796502%26dopt%3DAbstract Authors: Deosarkar SP, Bhatt P, Lewis CJ, Goetz DJ Pathological inflammation and endothelial dysfunction in atherosclerosis causes endothelial cell detachment from affected vasculature giving rise to circulating endothelial cells (CECs). A blood-based assay that can detect and characterize CECs in atherosclerosis could serve as a valuable diagnostic. Thus, we sought to develop a prototypic assay that detects and characterizes the inflammatory state of endothelial cells present in blood. For this purpose, we spiked resting and inflamed human umbilical vein endothelial cells (HUVEC) into separate samples of whole blood. RNA was harvested and analyzed via quantitative real-time PCR (qPCR) using melanoma cell adhesion molecule (MCAM), as an endothelial marker, and vascular cell adhesion mo... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103982 Wed, 27 Jul 2011 23:00:00 +0100 5103982 http://www.medworm.com/index.php?rid=5103987&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21785882%26dopt%3DAbstract The objective of this study was to develop full body CAD geometry of a seated 50th percentile male. Model development was based on medical image data acquired for this study, in conjunction with extensive data from the open literature. An individual (height, 174.9 cm, weight, 78.6 ± 0.77 kg, and age 26 years) was enrolled in the study for a period of 4 months. 72 scans across three imaging modalities (CT, MRI, and upright MRI) were collected. The whole-body dataset contains 15,622 images. Over 300 individual components representing human anatomy were generated through segmentation. While the enrolled individual served as a template, segmented data were verified against, or augmented with, data from over 75 literature sources on the average morphology of the human body. Non-Uniform R... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103987 Fri, 22 Jul 2011 23:00:00 +0100 5103987 http://www.medworm.com/index.php?rid=5103986&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21785883%26dopt%3DAbstract This study presents a lung surrogate prototype designed to expand the injury assessment capabilities of ATDs to include a risk measure for pulmonary contusion (PC). The surrogate augments these existing measures by providing pressure data specific to the lung and its lobes. The prototype was created from a rendering of a 50th percentile male lung inflated to normal inspiration, obtained from clinical CT data. Surrogate size, lobe volume, and airway cross sections were selected to match the morphology of the lung. Elastomeric urethane was molded via rapid prototyping to create a functional prototype. Pressure sensors in each of the five terminal airways independently monitored pressure traces in the lobes during impacts to the surrogate. Software was created to analyze the surrogate impact ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103986 Thu, 21 Jul 2011 23:00:00 +0100 5103986 http://www.medworm.com/index.php?rid=5103985&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21785884%26dopt%3DAbstract Authors: Morlacchi S, Keller B, Arcangeli P, Balzan M, Migliavacca F, Dubini G, Gunn J, Arnold N, Narracott A, Evans D, Lawford P A model that combines the results of in vivo experiment, 3D image data, and computer simulation has been developed. Twelve identical stents were implanted into six healthy pigs and explanted at a range of different post-recovery periods from 6 h to 28 days. The stented vessel segments were embedded in methacrylate resin for the preparation of transverse histological sections and imaged using ultra-high resolution micro-CT. The resulting CT data was used to reconstruct the 3D geometry of the stents and one case was used to inform a 3D computational fluid dynamic model. Derived hemodynamic parameters such as wall shear stress (WSS), axial WSS, and oscillator... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5103985 Thu, 21 Jul 2011 23:00:00 +0100 5103985 http://www.medworm.com/index.php?rid=5058074&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21773854%26dopt%3DAbstract Authors: Walker JM, Myers AM, Schluchter MD, Goldberg VM, Caplan AI, Berilla JA, Mansour JM, Welter JF The feasibility of using ultrasound technology as a noninvasive, nondestructive method for evaluating the mechanical properties of engineered weight-bearing tissues was evaluated. A fixture was designed to accurately and reproducibly position the ultrasound transducer normal to the test sample surface. Agarose hydrogels were used as phantoms for cartilage to explore the feasibility of establishing correlations between ultrasound measurements and commonly used mechanical tissue assessments. The hydrogels were fabricated in 1-10% concentrations with a 2-10 mm thickness. For each concentration and thickness, six samples were created, for a total of 216 gel samples. Speed of sound was de... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5058074 Tue, 19 Jul 2011 23:00:00 +0100 5058074 http://www.medworm.com/index.php?rid=5058078&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21769539%26dopt%3DAbstract Authors: Clark AR, Stokes YM, Thompson JG In vitro maturation (IVM) of mammalian oocytes provides an alternative to traditional in vitro fertilization techniques for clinical treatment of infertility or animal breeding. IVM involves the collection of oocytes from the ovary prior to ovulation, with maturation occurring in a laboratory environment. The success of IVM is highly sensitive to the in vitro nutrient environment. The nurse cells surrounding the oocyte, known as cumulus cells, regulate this environment and removal of these cells reduces the ability of the oocyte to develop following insemination. Determining the nature of the interaction between the oocyte and cumulus cells, collectively called the cumulus-oocyte complex (COC), is a difficult task experimentally. Here we use a ... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5058078 Fri, 15 Jul 2011 23:00:00 +0100 5058078 http://www.medworm.com/index.php?rid=5058077&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21769540%26dopt%3DAbstract Authors: Salifu AA, Nury BD, Lekakou C Electrospinning was used in innovative electrospinning rigs to obtain tubular and flat fibrous structures with controlled fiber orientation with the aim to be used as scaffolds for biomedical applications, more specifically in the tissue engineering of vascular and orthopedic grafts. Gelatine and hydroxyapatite (HA)-gelatine solutions of various compositions were tried and electrospinning of continuous fibers was maintained for gelatine and up to 0.30 g/g HA-gelatine solutions in 2,2,2-trifluoroethanol (TFE). Small diameter tubular scaffolds were electrospun with axial fiber orientation and flat scaffolds were cut from fiber mats electrospun around a wired drum substrate. The fibrous mats were crosslinked using a glutaraldehyde solution and subje... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5058077 Fri, 15 Jul 2011 23:00:00 +0100 5058077 http://www.medworm.com/index.php?rid=5058076&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21769541%26dopt%3DAbstract Authors: Shah AR, Shah SR, Oh S, Ong JL, Wenke JC, Agrawal CM Regeneration of bone in large segmental bone defects requires regeneration of both cortical bone and trabecular bone. A scaffold design consisting of a hydroxyapatite (HA) ring surrounding a polylactic acid (PLA) core simulates the structure of bone and provides an environment for indirect and direct co-culture conditions. In this experiment, human umbilical vein endothelial cells (EC) and normal human primary osteoblasts (OB) were co-cultured to evaluate cell migration and interactions within this biphasic composite scaffold. Both cell types were able to migrate between the different material phases of the scaffold. It was also observed that OB migration increased when they were co-cultured with ECs, whereas EC migration de... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5058076 Fri, 15 Jul 2011 23:00:00 +0100 5058076 http://www.medworm.com/index.php?rid=5058075&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21769542%26dopt%3DAbstract In conclusion, we proposed a portable and easy-to-operate system in assessing the relative increase in penile perfusion after brief ischemia. The PPI thus obtained correlated significantly with serum testosterone levels as well as key anthropometric and serum biochemical parameters even in apparently healthy young adults, suggesting its potential as a sensitive tool in monitoring penile vascular function and risk for ED. PMID: 21769542 [PubMed - as supplied by publisher] (Source: Annals of Biomedical Engineering) Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5058075 Fri, 15 Jul 2011 23:00:00 +0100 5058075 http://www.medworm.com/index.php?rid=5058079&cid=s_37517_169_f&fid=37517&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21761242%26dopt%3DAbstract Authors: Anderson DE, Hinds MT The effects of flow on endothelial cells (ECs) have been widely examined for the ability of fluid shear stress to alter cell morphology and function; however, the effects of EC morphology without flow have only recently been observed. An increase in lithographic techniques in cell culture spurred a corresponding increase in research aiming to confine cell morphology. These studies lead to a better understanding of how morphology and cytoskeletal configuration affect the structure and function of the cells. This review examines EC micropatterning research by exploring both the many alternative methods used to alter EC morphology and the resulting changes in cellular shape and phenotype. Micropatterning induced changes in EC proliferation, apoptosis, cytosk... Annals of Biomedical Engineering journals http://www.medworm.com/rss/comments.php?id=5058079 Thu, 14 Jul 2011 23:00:00 +0100 5058079