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This page shows you the most recent publications within this specialty of the MedWorm directory. This is page number 9.
Collagen crosslinking does not dictate stiffness in a transgenic mouse model of skeletal muscle fibrosis
Skeletal muscle fibrosis is marked by increases in tissue stiffness and collagen content. However, only a very weak correlation exists between collagen content and stiffness in skeletal muscle. Recently, it has been hypothesized that collagen crosslinking explains tissue stiffness in fibrotic skeletal muscle. Therefore, we addressed this hypothesis by correlating tissue stiffness with lysyl-pyridinoline, hydroxylysyl-pyridinoline, and pentosidine collagen crosslinks. Stepwise regression revealed that, separate or together, collagen crosslinks did not correlate with tissue stiffness. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - December 9, 2014 Category: Biomedical Science Authors: Mark A. Chapman, Rajeswari Pichika, Richard L. Lieber Tags: Short communication Source Type: research
Biomechanical benefits of the onion-skin motor unit control scheme
Muscle force is modulated by varying the number of active motor units and their firing rates. For the past five decades, the notion that the magnitude of the firing rates is directly related to motor unit size and recruitment threshold has been widely accepted. This construct, here named the After-hyperpolarization scheme evolved from observations in electrically stimulated cat motoneurons and from reported observations in voluntary contractions in humans. It supports the assumption that the firing rates of motor units match their mechanical properties to “optimize” force production, so that the firing rate range corre...
Source: Journal of Biomechanics - December 9, 2014 Category: Biomedical Science Authors: Carlo J De Luca, Paola Contessa Source Type: research
Damping and energy dissipation in soft tissue Vibrations during running
In this study, these modes are extracted applying a recently developed method namely, partly ensemble empirical mode decomposition (PEEMD). Then, a methodology for estimating the damping properties and energy dissipation caused by damping for each mode is used. Applying this methodology on simulated signals demonstrates high accuracy. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - December 9, 2014 Category: Biomedical Science Authors: Arash Khassetarash, Reza Hassannejad, Hendrik Enders, Mir Mohammad Ettefagh Source Type: research
Quantifying skeletal muscle recovery in A rat injury model using ultrasound imaging
Monitoring skeletal muscle health during recovery or degeneration is of great interest both clinically and in research settings. This type of monitoring requires health measurements be taken at multiple time points. Contraction strength is a commonly used metric for quantifying muscle health, but it requires invasive in vitro or in situ procedures that may further damage the tissue. Ultrasound imaging can be used to visualize muscle damage, and semi-quantitative grading scales have been shown to be effective at characterizing abnormalities. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - December 9, 2014 Category: Biomedical Science Authors: Matt Leineweber, Yingxin Gao Tags: Short communication Source Type: research
Cardiac fluid Dynamics Anticipates heart adaptation
Hemodynamic forces represent an epigenetic factor during heart development and are supposed to influence the pathology of the grown heart. Cardiac blood motion is characterized by a vortical dynamics, and it is common belief that the cardiac vortex has a role in disease progressions or regression. Here we provide a preliminary demonstration about the relevance of maladaptive intra-cardiac vortex dynamics in the geometrical adaptation of the dysfunctional heart. We employed an in vivo model of patients who present a stable normal heart function in virtue of the cardiac resynchronization therapy (CRT, bi-ventricular pace-mak...
Source: Journal of Biomechanics - December 9, 2014 Category: Biomedical Science Authors: Gianni Pedrizzetti, Alfonso R. Martiniello, Valter Bianchi, Antonio D’Onofrio, Pio Caso, Giovanni Tonti Tags: Short communication Source Type: research
A low cost real-time motion tracking approach using webcam technology
Physical therapy is an important component of gait recovery for individuals with locomotor dysfunction. There is a growing body of evidence that suggests that incorporating a motor learning task through visual feedback of movement trajectory is a useful approach to facilitate therapeutic outcomes. Visual feedback is typically provided by recording the subject’s limb movement patterns using a three-dimensional motion capture system and displaying it in real-time using customized software. However, this approach can seldom be used in the clinic because of the technical expertise required to operate this device and the cost...
Source: Journal of Biomechanics - December 9, 2014 Category: Biomedical Science Authors: Chandramouli Krishnan, Edward P. Washabaugh, Yogesh Seetharaman Tags: Short communication Source Type: research
The extent of altered digit force direction correlates with clinical upper extremity impairment in chronic stroke survivors
This study examined the relation between the ability to precisely direct fingertip force and clinical hand function scores among individuals affected by stroke. Specifically, clinical hand function tests of the Fugl-Meyer, Chedoke McMaster, and Box and Block Test were used, since they involve various hand movements required for activities of daily living. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - December 9, 2014 Category: Biomedical Science Authors: Na Jin Seo, Leah R. Enders, Binal Motawar, Marcella S. Kosmopoulos, Mojtaba Fathi-Firoozabad Tags: Short communication Source Type: research
Biomechanical study on the bladder neck and urethral positions: Simulation of impairment of the pelvic ligaments
Excessive mobility of the bladder neck and urethra are common features in stress urinary incontinence. We aimed at assessing, through computational modelling, the bladder neck position taking into account progressive impairment of the pelvic ligaments.Magnetic Resonance images of a young healthy female were used to build a computational model of the pelvic cavity. Appropriate material properties and constitutive models were defined. The impairment of the ligaments was simulated by mimicking a reduction in their stiffness. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - December 9, 2014 Category: Biomedical Science Authors: Sofia Brandão, Marco Parente, Teresa Mascarenhas, Ana Rita Gomes da Silva, Isabel Ramos, Renato Natal Jorge Source Type: research
Quantitative analysis of imprint shape and its relation to mechanical properties measured by microindentation in bone
Microindentation in bone is a micromechanical testing technique routinely used to extract material properties related to bone quality. As the analysis of microindentation data is based on assumptions about the contact between sample and surface, the aim of this study was to quantify the topological variability of indentations in bone and examine its relationship with mechanical properties. Indentations were performed in dry human and ovine bone in axial and transverse directions and their topology was measured by atomic force microscopy. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - December 9, 2014 Category: Biomedical Science Authors: J.J. Schwiedrzik, P.K. Zysset Source Type: research
Intermittent hypoxic resistance training: Is metabolic stress the key moderator?
Traditionally, researchers and practitioners have manipulated acute resistance exercise variables to elicit the desired responses to training. However, recent research indicates that altering the muscular environment during resistance training, namely by implementing a hypoxic stimulus, can augment muscle hypertrophy and strength. Intermittent hypoxic resistance training (IHRT), whereby participants inspire hypoxic air during resistance training, has been previously demonstrated to increase muscle cross-sectional area and maximum strength by significantly greater amounts than the equivalent training in normoxia. (Source: Medical Hypotheses)
Source: Medical Hypotheses - December 9, 2014 Category: Biomedical Science Authors: Brendan R. Scott, Katie M Slattery, Ben J Dascombe Source Type: research
Genetic algorithm-based method for mitigating label noise issue in ECG signal classification
Publication date: Available online 27 November 2014 Source:Biomedical Signal Processing and Control Author(s): Edoardo Pasolli , Farid Melgani Classification of electrocardiographic (ECG) signals can be deteriorated by the presence in the training set of mislabeled samples. To alleviate this issue we propose a new approach that aims at assisting the human user (cardiologist) in his/her work of labeling by removing in an automatic way the training samples with potential mislabeling problems. The proposed method is based on a genetic optimization process, in which each chromosome represents a candidate solution for validat...
Source: Biomedical Signal Processing and Control - December 9, 2014 Category: Biomedical Science Source Type: research
Maximally informative foraging by Caenorhabditis elegans
Animals have evolved intricate search strategies to find new sources of food. Here, we analyze a complex food seeking behavior in the nematode Caenorhabditis elegans (C. elegans) to derive a general theory describing different searches. We show that C. elegans, like many other animals, uses a multi-stage search for food, where they initially explore a small area intensively (‘local search’) before switching to explore a much larger area (‘global search’). We demonstrate that these search strategies as well as the transition between them can be quantitatively explained by a maximally informative sear...
Source: eLife - December 9, 2014 Category: Biomedical Science Authors: Calhoun, A. J., Chalasani, S. H., Sharpee, T. O. Tags: Neuroscience Source Type: research
Spatial quality control bypasses cell-based limitations on proteostasis to promote prion curing
The proteostasis network has evolved to support protein folding under normal conditions and to expand this capacity in response to proteotoxic stresses. Nevertheless, many pathogenic states are associated with protein misfolding, revealing in vivo limitations on quality control mechanisms. One contributor to these limitations is the physical characteristics of misfolded proteins, as exemplified by amyloids, which are largely resistant to clearance. However, other limitations imposed by the cellular environment are poorly understood. To identify cell-based restrictions on proteostasis capacity, we determined the mechanism b...
Source: eLife - December 9, 2014 Category: Biomedical Science Authors: Klaips, C. L., Hochstrasser, M. L., Langlois, C. R., Serio, T. R. Tags: Cell biology Source Type: research
Dynamic Conformations of Nucleophosmin (NPM1) at a Key Monomer-Monomer Interface Affect Oligomer Stability and Interactions with Granzyme B
by Wei D. Duan-Porter, Virgil L. Woods, Kimberly D. Maurer, Sheng Li, Antony Rosen Nucleophosmin (NPM1) is an abundant, nucleolar tumor antigen with important roles in cell proliferation and putative contributions to oncogenesis. Wild-type NPM1 forms pentameric oligomers through interactions at the amino-terminal core domain. A truncated form of NPM1 found in some hepatocellular carcinoma tissue formed an unusually stable oligomer and showed increased susceptibility to cleavage by granzyme B. Initiation of translation at the seventh methionine generated a protein (M7-NPM) that shared all these properties. We used deuteriu...
Source: PLoS One - December 9, 2014 Category: Biomedical Science Authors: Wei D. Duan-Porter et al. Source Type: research
Colorful Protein-Based Fluorescent Probes for Collagen Imaging
by Stijn J. A. Aper, Ariane C. C. van Spreeuwel, Mark C. van Turnhout, Ardjan J. van der Linden, Pascal A. Pieters, Nick L. L. van der Zon, Sander L. de la Rambelje, Carlijn V. C. Bouten, Maarten Merkx Real-time visualization of collagen is important in studies on tissue formation and remodeling in the research fields of developmental biology and tissue engineering. Our group has previously reported on a fluorescent probe for the specific imaging of collagen in live tissue in situ, consisting of the native collagen binding protein CNA35 labeled with fluorescent dye Oregon Green 488 (CNA35-OG488). The CNA35-OG488 probe has...
Source: PLoS One - December 9, 2014 Category: Biomedical Science Authors: Stijn J. A. Aper et al. Source Type: research
The Prevalence and Prognosis of Resistant Hypertension in Patients with Heart Failure
Conclusions Resistant hypertension appears to be not associated with adverse clinical outcome in patients with heart failure, in fact may be a protective factor for reduced heart failure related re-hospitalization in patients with reduced ejection fraction. (Source: PLoS One)
Source: PLoS One - December 9, 2014 Category: Biomedical Science Authors: Chun-Na Jin et al. Source Type: research
Effects of Mulching Tolerant Plant Straw on Soil Surface on Growth and Cadmium Accumulation of Galinsoga parviflora
by Lijin Lin, Ming’an Liao, Yajun Ren, Li Luo, Xiao Zhang, Daiyu Yang, Jing He Pot and field experiments were conducted to study the effects of mulching with straw of cadmium (Cd) tolerant plants (Ranunculus sieboldii, Mazus japonicus, Clinopodium confine and Plantago asiatica) on growth and Cd accumulation of Galinsoga parviflora in Cd-contaminated soil. In the pot experiment, mulching with M. japonicus straw increased the root biomass, stem biomass, leaf biomass, shoot biomass, plant height and activities of antioxidant enzymes (superoxide dismutase, peroxidase and catalase) of G. parviflora compared with the control,...
Source: PLoS One - December 9, 2014 Category: Biomedical Science Authors: Lijin Lin et al. Source Type: research
Association between Recruitment Methods and Attrition in Internet-Based Studies
by Paolo Bajardi, Daniela Paolotti, Alessandro Vespignani, Ken Eames, Sebastian Funk, W. John Edmunds, Clement Turbelin, Marion Debin, Vittoria Colizza, Ronald Smallenburg, Carl Koppeschaar, Ana O. Franco, Vitor Faustino, AnnaSara Carnahan, Moa Rehn, Franco Merletti, Jeroen Douwes, Ridvan Firestone, Lorenzo Richiardi Internet-based systems for epidemiological studies have advantages over traditional approaches as they can potentially recruit and monitor a wider range of individuals in a relatively inexpensive fashion. We studied the association between communication strategies used for recruitment (offline, online, face-t...
Source: PLoS One - December 9, 2014 Category: Biomedical Science Authors: Paolo Bajardi et al. Source Type: research
Road Development and the Geography of Hunting by an Amazonian Indigenous Group: Consequences for Wildlife Conservation
by Santiago Espinosa, Lyn C. Branch, Rubén Cueva Protected areas are essential for conservation of wildlife populations. However, in the tropics there are two important factors that may interact to threaten this objective: 1) road development associated with large-scale resource extraction near or within protected areas; and 2) historical occupancy by traditional or indigenous groups that depend on wildlife for their survival. To manage wildlife populations in the tropics, it is critical to understand the effects of roads on the spatial extent of hunting and how wildlife is used. A geographical analysis can help us answe...
Source: PLoS One - December 9, 2014 Category: Biomedical Science Authors: Santiago Espinosa et al. Source Type: research
Novel DNA Topoisomerase IIα Inhibitors from Combined Ligand- and Structure-Based Virtual Screening
by Malgorzata N. Drwal, Jessica Marinello, Stefano G. Manzo, Laurence P. G. Wakelin, Giovanni Capranico, Renate Griffith DNA topoisomerases are enzymes responsible for the relaxation of DNA torsional strain, as well as for the untangling of DNA duplexes after replication, and are important cancer drug targets. One class of topoisomerase inhibitors, “poisons”, binds to the transient enzyme-DNA complex which occurs during the mechanism of action, and inhibits the religation of DNA. This ultimately leads to the accumulation of DNA double strand breaks and cell death. Different types of topoisomerases occur in human cells...
Source: PLoS One - December 9, 2014 Category: Biomedical Science Authors: Malgorzata N. Drwal et al. Source Type: research
The Denitrification Characteristics of Pseudomonas stutzeri SC221-M and Its Application to Water Quality Control in Grass Carp Aquaculture
by Bin Deng, Luoqin Fu, Xiaoping Zhang, Jiajia Zheng, Lisha Peng, Jiandong Sun, Haiyan Zhu, Yibing Wang, Weifen Li, Xuexiang Wu, Di Wu To reduce ammonium and nitrite in aquaculture water, an isolate of the denitrifying bacterium Pseudomonas stutzeri, SC221-M, was obtained. The effects of various nitrogen and carbon sources, the ratio of carbon to nitrogen and temperature on bacterial growth, denitrification rates and the expression levels of nirS and nosZ in SC221-M were studied. The following conditions were determined to be optimal for growth and denitrification in SC221-M: NaNO2 as the nitrogen source, sodium citrate a...
Source: PLoS One - December 9, 2014 Category: Biomedical Science Authors: Bin Deng et al. Source Type: research
Computational Pathology to Discriminate Benign from Malignant Intraductal Proliferations of the Breast
by Fei Dong, Humayun Irshad, Eun-Yeong Oh, Melinda F. Lerwill, Elena F. Brachtel, Nicholas C. Jones, Nicholas W. Knoblauch, Laleh Montaser-Kouhsari, Nicole B. Johnson, Luigi K. F. Rao, Beverly Faulkner-Jones, David C. Wilbur, Stuart J. Schnitt, Andrew H. Beck The categorization of intraductal proliferative lesions of the breast based on routine light microscopic examination of histopathologic sections is in many cases challenging, even for experienced pathologists. The development of computational tools to aid pathologists in the characterization of these lesions would have great diagnostic and clinical value. As a first ...
Source: PLoS One - December 9, 2014 Category: Biomedical Science Authors: Fei Dong et al. Source Type: research
High Amylose Resistant Starch Diet Ameliorates Oxidative Stress, Inflammation, and Progression of Chronic Kidney Disease
by Nosratola D. Vaziri, Shu-Man Liu, Wei Ling Lau, Mahyar Khazaeli, Sohrab Nazertehrani, Seyed H. Farzaneh, Dorothy A. Kieffer, Sean H. Adams, Roy J. Martin Inflammation is a major mediator of CKD progression and is partly driven by altered gut microbiome and intestinal barrier disruption, events which are caused by: urea influx in the intestine resulting in dominance of urease-possessing bacteria; disruption of epithelial barrier by urea-derived ammonia leading to endotoxemia and bacterial translocation; and restriction of potassium-rich fruits and vegetables which are common sources of fermentable fiber. Restriction of ...
Source: PLoS One - December 9, 2014 Category: Biomedical Science Authors: Nosratola D. Vaziri et al. Source Type: research
Pancreatic Ductal Adenocarcinoma Treatment – The Past, Present and Future
Until 1898, when Halsted performed the first transduodenal local excision of a tumor arising from the ampulla of Vater, and Codivilla performed the first en bloc resection of the pancreatic head and duodenum, surgery on the periampullary region was not thought feasible or safe. Even after these technical feats, pancreatic surgery was not widely disseminated because the procedure-related mortality rate approached 100%. Three major breakthroughs in medical science over the subsequent thirty years paved the way for the expansion of pancreatic surgery. (Source: Seminars in Oncology)
Source: Seminars in Oncology - December 9, 2014 Category: Cancer & Oncology Authors: Harish Lavu, Charles J. Yeo Source Type: research
Communicable Diseases Surveillance System in East Azerbaijan Earthquake: Strengths and Weaknesses
Conclusion The established surveillance system functioned well in controlling CDs in the earthquake-stricken regions of East Azerbaijan. Because, no significant outbreak was reported until the end of December 2012 (when the surveillance system was active) although it was summer and the affected regions were susceptible to outbreaks of CD. However, there were some weaknesses in implementing and developing the SS. Considering the susceptibility of Iran to various natural hazards, designing a web-based surveillance system for recording and collecting data is essential at the time of disaster. The authors also suggest that re...
Source: PLOS Currents Disasters - December 8, 2014 Category: Global & Universal Authors: javad Source Type: research
Bacterial Detection Testing by Blood and Blood Collection Establishments and Transfusion Services to Enhance the Safety and Availability of Platelets for Transfusion: Draft Guidance for Industry
(Source: What's New at CBER)
Source: What's New at CBER - December 8, 2014 Category: Biomedical Science Source Type: news
Bone adaptation to cyclic loading in murine caudal vertebrae Is maintained with age and directly correlated to the local micromechanical environment
The ability of the skeleton to adapt to mechanical stimuli (mechanosensitivity) has most often been investigated at the whole-bone level, but less is known about the local mechanoregulation of bone remodeling at the bone surface, especially in context of the aging skeleton. The aim of this study was to determine the local and global mechanosensitivity of the sixth caudal vertebra during cyclic loading (8N, three times per week, for six weeks) in mice aged 15, 52, and 82 weeks at the start of loading. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - December 8, 2014 Category: Biomedical Science Authors: Floor M. Lambers, Gisela Kuhn, Claudia Weigt, Kathleen M. Koch, Friederike A. Schulte, Ralph Müller Source Type: research
Possible role for microRNAs as inter-species mediators of epigenetic information in disease pathogenesis: is the non-coding dark matter of the genome responsible for epigenetic interindividual or interspecies communication?
MicroRNAs are short non-coding RNA molecules involved in the posttranscriptional epigenetic regulation of gene expression. Recent data show that microRNAs can be found in body fluids, and these microRNAs might enter cells giving rise to a hormone like way of action. MicroRNAs released in body fluids might affect other individuals, and there are some data of potential cross-species action of microRNAs, as well. Here, the authors discuss hypotheses concerning the potential pathogenic relevance of interindividual and cross-species action of microRNAs including food-derived microRNAs. (Source: Medical Hypotheses)
Source: Medical Hypotheses - December 8, 2014 Category: Biomedical Science Authors: I. Igaz, P. Igaz Source Type: research
Ambiguities in helical reconstruction
Helical polymers are found throughout biology and account for a substantial fraction of the protein in a cell. These filaments are very attractive for three-dimensional reconstruction from electron micrographs due to the fact that projections of these filaments show many different views of identical subunits in identical environments. However, ambiguities exist in defining the symmetry of a helical filament when one has limited resolution, and mistakes can be made. Until one reaches a near-atomic level of resolution, there are not necessarily reality-checks that can distinguish between correct and incorrect solutions. A re...
Source: eLife - December 8, 2014 Category: Biomedical Science Authors: Egelman, E. H. Tags: Biophysics and structural biology Source Type: research
Inverse Association between High Blood 25-Hydroxyvitamin D Levels and Diabetic Retinopathy in a Representative Korean Population
Conclusions This study provides the first epidemiologic findings of the inverse relationships of blood 25-hydroxyvitamin D levels with any DR and proliferative DR only in men. Considering anti-angiogenic and anti-fibrotic action of vitamin D, further studies including longitudinal and interventional analysis are warranted. (Source: PLoS One)
Source: PLoS One - December 8, 2014 Category: Biomedical Science Authors: Donghyun Jee et al. Source Type: research
The Transcriptome of Legionella pneumophila-Infected Human Monocyte-Derived Macrophages
Conclusion/Significance Taken together, the hMDM transcriptional response to L. pneumophila is independent of intra-vacuolar replication of the bacteria and primarily involves modulation of the immune response and metabolic as well as nutritional pathways. (Source: PLoS One)
Source: PLoS One - December 8, 2014 Category: Biomedical Science Authors: Christopher T. D. Price et al. Source Type: research
Molecular and Cellular Characterization of a Zebrafish Optic Pathway Tumor Line Implicates Glia-Derived Progenitors in Tumorigenesis
In this study we describe the molecular and cellular characterization of a zebrafish mutant that develops tumors in the optic pathway. Heterozygous Tg(flk1:RFP)is18 transgenic adults develop tumors of the retina, optic nerve and optic tract. Molecular and genetic mapping demonstrate the tumor phenotype is linked to a high copy number transgene array integrated in the lincRNA gene lincRNAis18/Zv9_00007276 on chromosome 3. TALENs were used to isolate a 147kb deletion allele that removes exons 2–5 of the lincRNAis18 gene. Deletion allele homozygotes are viable and do not develop tumors, indicating loss of function of the li...
Source: PLoS One - December 8, 2014 Category: Biomedical Science Authors: Staci L. Solin et al. Source Type: research
Pain Reduction and Financial Incentives to Improve Glucose Monitoring Adherence in a Community Health Center
We present a small pilot study to explore whether the use of financial incentives and pain-free lancets could improve adherence to glucose testing in a community health center patient population consisting largely of non-English speaking ethnic minorities with low health literacy. The proportion of patients lost to follow-up was 17%, suggesting that a larger scale study is feasible in this type of setting, but we found no preliminary evidence suggesting a positive effect on adherence by either financial incentives or pain-free lancets. Results from this pilot study will guide the design of larger-scale studies to evaluate ...
Source: PLoS One - December 8, 2014 Category: Biomedical Science Authors: Mary Ann H. Huntsman et al. Source Type: research
Suicides, Homicides, Accidents, and Other External Causes of Death among Blacks and Whites in the Southern Community Cohort Study
by Jennifer S. Sonderman, Heather M. Munro, William J. Blot, Robert E. Tarone, Joseph K. McLaughlin Prior studies of risk factors associated with external causes of death have been limited in the number of covariates investigated and external causes examined. Herein, associations between numerous demographic, lifestyle, and health-related factors and the major causes of external mortality, such as suicide, homicide, and accident, were assessed prospectively among 73,422 black and white participants in the Southern Community Cohort Study (SCCS). Hazard ratios (HR) and 95% confidence intervals (CI) were calculated in multiv...
Source: PLoS One - December 8, 2014 Category: Biomedical Science Authors: Jennifer S. Sonderman et al. Source Type: research
Smooth Muscle Strips for Intestinal Tissue Engineering
by Christopher M. Walthers, Min Lee, Benjamin M. Wu, James C. Y. Dunn Functionally contracting smooth muscle is an essential part of the engineered intestine that has not been replicated in vitro. The purpose of this study is to produce contracting smooth muscle in culture by maintaining the native smooth muscle organization. We employed intact smooth muscle strips and compared them to dissociated smooth muscle cells in culture for 14 days. Cells isolated by enzymatic digestion quickly lost maturity markers for smooth muscle cells and contained few enteric neural and glial cells. Cultured smooth muscle strips exhibited pe...
Source: PLoS One - December 8, 2014 Category: Biomedical Science Authors: Christopher M. Walthers et al. Source Type: research
Inactivation of the Rgg2 Transcriptional Regulator Ablates the Virulence of Streptococcus pyogenes
by Anastasia A. Zutkis, Srivishnupriya Anbalagan, Michael S. Chaussee, Alexander V. Dmitriev Streptococcus pyogenes adapts to different niches encountered in the human host via the activity of numerous regulatory proteins including the Rgg family of transcriptional regulators. The S. pyogenes chromosome encodes four Rgg paralogues designated Rgg1 (RopB), Rgg2 (MutR), Rgg3, and Rgg4 (ComR). In order to understand the role of the Rgg2 protein in the regulation of metabolic and virulence-associated properties of S. pyogenes, the rgg2 gene was inactivated in the M1 serotype strain SF370. Inactivation of rgg2 increased the gro...
Source: PLoS One - December 8, 2014 Category: Biomedical Science Authors: Anastasia A. Zutkis et al. Source Type: research
Amelioration of Hypercholesterolemia by an EGFR Tyrosine Kinase Inhibitor in Mice with Liver-Specific Knockout of Mig-6
In this study, we investigated the effects of EGFR inhibition to identify a potential new treatment target for hypercholesterolemia. We used a mouse model with conditional ablation of the Mig-6 gene in the liver (Albcre/+Mig-6f/f; Mig-6d/d) to effectively investigate the role of Mig-6 in the regulation of liver function. Mig-6d/d mice were treated with either the EGFR inhibitor gefitinib or statin for 6 weeks after administration of a high-fat or standard diet. We then compared lipid profiles and other parameters among each group of mice. After a high-fat diet, Mig-6d/d mice showed elevated serum levels of total cholestero...
Source: PLoS One - December 8, 2014 Category: Biomedical Science Authors: Jun Choul Lee et al. Source Type: research
Association between NME8 Locus Polymorphism and Cognitive Decline, Cerebrospinal Fluid and Neuroimaging Biomarkers in Alzheimer's Disease
by Ying Liu, Jin-Tai Yu, Hui-Fu Wang, Xiao-Ke Hao, Yu-Fen Yang, Teng Jiang, Xi-Chen Zhu, Lei Cao, Dao-Qiang Zhang, Lan Tan Recently, a large meta-analysis of five genome wide association studies (GWAS) identified a novel locus (rs2718058) adjacent to NME8 that played a preventive role in Alzheimer's disease (AD). However, this link between the single nucleotide polymorphism (SNP) rs2718058 and the pathology of AD have not been mentioned yet. Therefore, this study assessed the strength of association between the NME8 rs2718058 genotypes and AD-related measures including the cerebrospinal fluid (CSF) amyloid beta, tau, P-ta...
Source: PLoS One - December 8, 2014 Category: Biomedical Science Authors: Ying Liu et al. Source Type: research
Molecular Cloning, Characterization and Positively Selected Sites of the Glutathione S-Transferase Family from Locusta migratoria
by Xueyao Zhang, Jianxin Wang, Min Zhang, Guohua Qin, Daqi Li, Kun Yan Zhu, Enbo Ma, Jianzhen Zhang Glutathione S-transferases (GSTs) are multifunctional enzymes that are involved in the metabolism of endogenous and exogenous compounds and are related to insecticide resistance. The purpose of this study was to provide new information on the molecular characteristics and the positive selection of locust GSTs. Based on the transcriptome database, we sequenced 28 cytosolic GSTs and 4 microsomal GSTs from the migratory locust (Locusta migratoria). We assigned the 28 cytosolic GSTs into 6 classes—sigma, epsilon, delta, theta...
Source: PLoS One - December 8, 2014 Category: Biomedical Science Authors: Xueyao Zhang et al. Source Type: research
Genome-wide mapping in a house mouse hybrid zone reveals hybrid sterility loci and Dobzhansky-Muller interactions
Mapping hybrid defects in contact zones between incipient species can identify genomic regions contributing to reproductive isolation and reveal genetic mechanisms of speciation. The house mouse features a rare combination of sophisticated genetic tools and natural hybrid zones between subspecies. Male hybrids often show reduced fertility, a common reproductive barrier between incipient species. Laboratory crosses have identified sterility loci, but each encompasses hundreds of genes. We map genetic determinants of testis weight and testis gene expression using offspring of mice captured in a hybrid zone between M. musculu...
Source: eLife - December 8, 2014 Category: Biomedical Science Authors: Turner, L. M., Harr, B. Tags: Genomics and evolutionary biology Source Type: research
Searching for the genes that separate species
Hybrid mice shed new light on the interactions between regions of the genome that help drive the evolution of new species by reducing the fertility of hybrid males. (Source: eLife)
Source: eLife - December 8, 2014 Category: Biomedical Science Authors: Phifer-Rixey, M. Tags: Evolution Source Type: research
Dopamine drives Drosophila sechellia adaptation to its toxic host
This study illustrates how an insect's dopaminergic system can sustain ecological adaptations by modulating ontogenesis and development. DOI: http://dx.doi.org/10.7554/eLife.03785.001 (Source: eLife)
Source: eLife - December 8, 2014 Category: Biomedical Science Authors: Lavista-Llanos, S., Svatos, A., Kai, M., Riemensperger, T., Birman, S., Stensmyr, M. C., Hansson, B. S. Tags: Neuroscience Source Type: research
Nanodomain coupling explains Ca2+ independence of transmitter release time course at a fast central synapse
A puzzling property of synaptic transmission, originally established at the neuromuscular junction, is that the time course of transmitter release is independent of the extracellular Ca2+ concentration ([Ca2+]o), whereas the rate of release is highly [Ca2+]o-dependent. Here, we examine the time course of release at inhibitory basket cell-Purkinje cell synapses and show that it is independent of [Ca2+]o. Modeling of Ca2+-dependent transmitter release suggests that the invariant time course of release critically depends on tight coupling between Ca2+ channels and release sensors. Experiments with exogenous Ca2+ chelators rev...
Source: eLife - December 8, 2014 Category: Biomedical Science Authors: Arai, I., Jonas, P. Tags: Neuroscience Source Type: research
The extraembryonic serosa is a frontier epithelium providing the insect egg with a full-range innate immune response
In this study, we test a possible immune function of this frontier epithelium using Tc-zen1 RNAi-mediated deletion. First, we show that bacteria propagate twice as fast in serosa-less eggs. Then, we compare the complete transcriptomes of wild-type, control RNAi, and Tc-zen1 RNAi eggs before and after sterile or septic injury. Infection induces genes involved in Toll and IMD-signaling, melanisation, production of reactive oxygen species and antimicrobial peptides in wild-type eggs but not in serosa-less eggs. Finally, we demonstrate constitutive and induced immune gene expression in the serosal epithelium using in situ hybr...
Source: eLife - December 8, 2014 Category: Biomedical Science Authors: Jacobs, C. G. C., Spaink, H. P., van der Zee, M. Tags: Immunology Source Type: research
Vocalization-whisking coordination and multisensory integration of social signals in rat auditory cortex
Social interactions involve multi-modal signaling. Here, we study interacting rats to investigate audio-haptic coordination and multisensory integration in the auditory cortex. We find that facial touch is associated with an increased rate of ultrasonic vocalizations, which are emitted at the whisking rate (~8 Hz) and preferentially initiated in the retraction phase of whisking. In a small subset of auditory cortex regular-spiking neurons, we observed excitatory and heterogeneous responses to ultrasonic vocalizations. Most fast-spiking neurons showed a stronger response to calls. Interestingly, facial touch-induced inhibit...
Source: eLife - December 8, 2014 Category: Biomedical Science Authors: Rao, R. P., Mielke, F., Bobrov, E., Brecht, M. Tags: Neuroscience Source Type: research
Dominant drug targets suppress the emergence of antiviral resistance
The emergence of drug resistance can defeat the successful treatment of pathogens that display high mutation rates, as exemplified by RNA viruses. Here we detail a new paradigm in which a single compound directed against a ‘dominant drug target’ suppresses the emergence of naturally occurring drug-resistant variants in mice and cultured cells. All new drug-resistant viruses arise during intracellular replication and initially express their phenotypes in the presence of drug-susceptible genomes. For the targets of most anti-viral compounds, the presence of these drug-susceptible viral genomes does not prevent th...
Source: eLife - December 8, 2014 Category: Biomedical Science Authors: Tanner, E. J., Liu, H.-m., Oberste, M. S., Pallansch, M., Collett, M. S., Kirkegaard, K. Tags: Human biology and medicine Source Type: research
Structural basis of diverse membrane target recognitions by ankyrins
Ankyrin adaptors together with their spectrin partners coordinate diverse ion channels and cell adhesion molecules within plasma membrane domains and thereby promote physiological activities including fast signaling in the heart and nervous system. Ankyrins specifically bind to numerous membrane targets through their 24 ankyrin repeats (ANK repeats), although the mechanism for the facile and independent evolution of these interactions has not been resolved. Here we report the structures of ANK repeats in complex with an inhibitory segment from the C-terminal regulatory domain and with a sodium channel Nav1.2 peptide, respe...
Source: eLife - December 8, 2014 Category: Biomedical Science Authors: Wang, C., Wei, Z., Chen, K., Ye, F., Yu, C., Bennett, V., Zhang, M. Tags: Biophysics and structural biology Source Type: research
The value proposition of case reports: Novelty, pedagogy, anecdotal aggregation, humanity
Some in scientific and academic circles downplay the importance of case reports, but clinical practitioners understand their value. Editors of medical science journals acknowledge the popularity of case reports, but most dedicate little space to them, citing a deleterious effect on the journal's metrics, most notably the Impact Factor. (Source: Nature Clinical Practice)
Source: Nature Clinical Practice - December 8, 2014 Category: Neurology Tags: From the Editor ' s Desk Source Type: research
The effects of apelin treatment on a rat model of type 2 diabetes
Conclusions Apelin can be used as a therapeutic agent in the treatment of type II diabetes in the future. (Source: Advances in Medical Sciences)
Source: Advances in Medical Sciences - December 7, 2014 Category: Biomedical Science Source Type: research
Change in enzyme production by gradually drying culture substrate during solid-state fermentation
Publication date: Available online 5 December 2014 Source:Journal of Bioscience and Bioengineering Author(s): Kazunari Ito , Katsuya Gomi , Masahiro Kariyama , Tsuyoshi Miyake The influence of drying the culture substrate during solid-state fermentation on enzyme production was investigated using a non-airflow box. The drying caused a significant increase in enzyme production, while the mycelium content decreased slightly. This suggests that changes in the water content in the substrate during culture affect enzyme production in fungi. (Source: Journal of Bioscience and Bioengineering)
Source: Journal of Bioscience and Bioengineering - December 7, 2014 Category: Biomedical Science Source Type: research