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This page shows you the most recent publications within this specialty of the MedWorm directory. This is page number 13.
Non‐invasive online detection of microbial lysine formation in stirred tank bioreactors by using calorespirometry
This study has proven that calorespirometry is a viable non‐invasive technique to detect product formation at any time point. Biotechnol. Bioeng. © 2012 Wiley Periodicals, Inc.
Source: Biotechnology and Bioengineering - December 27, 2012 Category: Biomedical Science Authors: Lars Regestein, Thomas Maskow, Andreas Tack, Ingo Knabben, Martin Wunderlich, Johannes Lerchner, Jochen Büchs Tags: Article Source Type: research
Construction of an inducible cell‐communication system that amplifies Salmonella gene expression in tumor tissue
Abstract Bacterial therapies have the potential to overcome resistances that cause chemotherapies to fail. When using bacteria to produce anticancer agents in tumors, triggering gene expression is necessary to prevent systemic toxicity.The use of chemical triggers, however, is hampered by poor delivery of inducing molecules, which reduces the number of activated bacteria. To solve this problem, we created a cell‐communication system that enables activated bacteria to induce inactive neighbors. We hypothesized that introducing cellcommunication into Salmonella would improve direct triggering strategies by increasing prote...
Source: Biotechnology and Bioengineering - December 27, 2012 Category: Biomedical Science Authors: Yumei Dai, Bhushan J. Toley, Charles A. Swofford, Neil S. Forbes Tags: Article Source Type: research
Comparative characterization of novel ene‐reductases from cyanobacteria
In this study, we characterized nine novel ERs from cyanobacterial strains belonging to different taxonomic orders and habitats. ERs were identified with activities towards a broad spectrum of alkenes. The reduction of maleimide was catalyzed with activities of up to 35.5 U mg−1 using NADPH. Ketoisophorone and (R)‐carvone, which were converted to the highly valuable compounds (R)‐levodione and (2R,5R)‐dihydrocarvone, were reduced with reaction rates of up to 2.2 U mg−1 with NADPH. In contrast to other homologous ERs from the literature, NADH was accepted at moderate to high rates as well: Enzyme activitie...
Source: Biotechnology and Bioengineering - December 27, 2012 Category: Biomedical Science Authors: Yilei Fu, Kathrin Castiglione, Dirk Weuster‐Botz Tags: Article Source Type: research
Biofilm model calibration and microbial diversity study using Monte Carlo simulations
Abstract Mathematical models are useful tools for studying and exploring biological conversion processes as well as microbial competition in biological treatment processes. A single‐species biofilm model was used to describe biofilm reactor operation at three different hydraulic retention times (HRT). The single‐species biofilm model was calibrated with sparse experimental data using the Monte Carlo filtering method. This calibrated single‐species biofilm model was then extended to a multi‐species model considering 10 different heterotrophic bacteria. The aim was to study microbial diversity in bulk phase biomass a...
Source: Biotechnology and Bioengineering - December 27, 2012 Category: Biomedical Science Authors: D. Brockmann, A. Caylet, R. Escudié, J.‐P. Steyer, N. Bernet Tags: Article Source Type: research
Global gene expression of Dehalococcoides within a robust dynamic TCE‐dechlorinating community under conditions of periodic substrate supply
Abstract A microarray targeting four sequenced strains in the Dehalococcoides (Dhc) genus was used to analyze gene expression in a robust long‐term trichloroethene (TCE)‐degrading microbial community (designated ANAS) during feeding cycles that involve conditions of periodic substrate supply. The Dhc transcriptome was examined at three time‐points throughout a batch feeding cycle: T1 (27 h) when TCE, dichloroethene (DCE), and vinyl chloride (VC) were present; T2 (54 h) when only VC remained; and T3 (13 d) when Dhc had been starved of substrate for nine days. 90% of the Dhc open reading frames (ORFs) that were det...
Source: Biotechnology and Bioengineering - December 27, 2012 Category: Biomedical Science Authors: Kimberlee A. West, Patrick K. H. Lee, David R. Johnson, Stephen H. Zinder, Lisa Alvarez‐Cohen Tags: Article Source Type: research
Pathways of reductive 2,4‐dinitroanisole (DNAN) biotransformation in sludge
Abstract As the use of the insensitive munition compound 2,4‐dinitroanisole (DNAN) increases, releases to the environment may pose a threat to local ecosystems. Little is known about the environmental fate of DNAN and the conversions caused by microbial activity. We studied DNAN biotransformation rates in sludge under aerobic, microaerophilic, and anaerobic conditions, detected biotransformation products, and elucidated their chemical structure. The biotransformation of DNAN was most rapid under anaerobic conditions with H2 as a cosubstrate. The results showed that the ortho nitro group in DNAN is regioselectively reduce...
Source: Biotechnology and Bioengineering - December 27, 2012 Category: Biomedical Science Authors: Christopher Olivares, Jidong Liang, Leif Abrell, Reyes Sierra‐Alvarez, Jim A. Field Tags: Article Source Type: research
A redox trap to augment the intein toolbox
Abstract The unregulated activity of inteins during expression and consequent side reactions during work‐up limits their widespread use in biotechnology and chemical biology. Therefore, we exploited a mechanism‐based approach to regulate intein autocatalysis for biotechnological application. The system, inspired by our previous structural studies, is based on reversible trapping of the intein's catalytic cysteine residue through a disulfide bond. Using standard mutagenesis, the disulfide trap can be implemented to impart redox control over different inteins and for a variety of applications both in vitro and in Escheri...
Source: Biotechnology and Bioengineering - December 27, 2012 Category: Biomedical Science Authors: Brian P. Callahan, Matthew Stanger, Marlene Belfort Tags: Article Source Type: research
Sequential Conformational Rearrangements Dictate the Dynamics of Class C GPCR Activation.
Abstract Heterotrimeric GTP-binding protein (G protein)-coupled receptors (GPCRs) are the largest family of cell surface receptors; they allow cells to respond to a wide range of endogenous and environmental signals. Class C GPCRs represent a discrete group within the GPCR family, with distinct structural characteristics. Receptors belonging to this class-such as γ-aminobutyric acid type B (GABA(B)) receptors or metabotropic glutamate receptors (mGluRs)-form constitutive dimers. However, the conformational changes within such a dimeric receptor that are associated with agonist activation are still not well underst...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Lane JR, Canals M Tags: Sci Signal Source Type: research
Attractor Landscape Analysis Reveals Feedback Loops in the p53 Network That Control the Cellular Response to DNA Damage.
Abstract The protein p53 functions as a tumor suppressor and can trigger either cell cycle arrest or apoptosis in response to DNA damage. We used Boolean network modeling and attractor landscape analysis to analyze the state transition dynamics of a simplified p53 network for which particular combinations of activation states of the molecules corresponded to specific cellular outcomes. Our results identified five critical interactions in the network that determined the cellular response to DNA damage, and simulations lacking any of these interactions produced states associated with sustained p53 activity, which cor...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Choi M, Shi J, Jung SH, Chen X, Cho KH Tags: Sci Signal Source Type: research
SUMOylation Silences Heterodimeric TASK Potassium Channels Containing K2P1 Subunits in Cerebellar Granule Neurons.
Abstract The standing outward K(+) current (IKso) governs the response of cerebellar granule neurons to natural and medicinal stimuli including volatile anesthetics. We showed that SUMOylation silenced half of IKso at the surface of cerebellar granule neurons because the underlying channels were heterodimeric assemblies of K2P1, a subunit subject to SUMOylation, and the TASK (two-P domain, acid-sensitive K(+)) channel subunits K2P3 or K2P9. The heterodimeric channels comprised the acid-sensitive portion of IKso and mediated its response to halothane. We anticipate that SUMOylation also influences sensation and home...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Plant LD, Zuniga L, Araki D, Marks JD, Goldstein SA Tags: Sci Signal Source Type: research
GPRC5B Activates Obesity-Associated Inflammatory Signaling in Adipocytes.
We report that GPRC5B-deficient mice were protected from diet-induced obesity and insulin resistance because of reduced inflammation in their white adipose tissue. GPRC5B is a lipid raft-associated transmembrane protein that contains multiple phosphorylated residues in its carboxyl terminus. Phosphorylation of GPRC5B by the tyrosine kinase Fyn and the subsequent direct interaction with Fyn through the Fyn Src homology 2 (SH2) domain were critical for the initiation and progression of inflammatory signaling in adipose tissue. We demonstrated that a GPRC5B mutant lacking the direct binding site for Fyn failed to activate a p...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Kim YJ, Sano T, Nabetani T, Asano Y, Hirabayashi Y Tags: Sci Signal Source Type: research
Remodeling a tissue: subtraction adds insight.
Abstract Sculpting a body plan requires both patterning of gene expression and translating that pattern into morphogenesis. Developmental biologists have made remarkable strides in understanding gene expression patterning, but despite a long history of fascination with the mechanics of morphogenesis, knowledge of how patterned gene expression drives the emergence of even simple shapes and forms has grown at a slower pace. The successful merging of approaches from cell biology, developmental biology, imaging, engineering, and mathematical and computational sciences is now accelerating progress toward a fuller and be...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Axelrod JD Tags: Sci Signal Source Type: research
Regulation of phosphatidylinositol-5-phosphate signaling by pin1 determines sensitivity to oxidative stress.
Abstract Oxidative signaling and oxidative stress contribute to aging, cancer, and diseases resulting from neurodegeneration. Pin1 is a proline isomerase that recognizes phosphorylated substrates and regulates the localization and conformation of its targets. Pin1(-/-) mice show phenotypes associated with premature aging, yet mouse embryonic fibroblasts (MEFs) from these mice are resistant to hydrogen peroxide (H(2)O(2))-induced cell death. We found that the abundance of phosphatidylinositol-5-phosphate (PtdIns5P) was increased in response to H(2)O(2), an effect that was enhanced in Pin1(-/-) MEFs. Reduction of H(2...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Keune WJ, Jones DR, Bultsma Y, Sommer L, Zhou XZ, Lu KP, Divecha N Tags: Sci Signal Source Type: research
Lack of the Phosphatase PTPN22 Increases Adhesion of Murine Regulatory T Cells to Improve Their Immunosuppressive Function.
Abstract The cytoplasmic phosphatase PTPN22 (protein tyrosine phosphatase nonreceptor type 22) plays a key role in regulating lymphocyte homeostasis, which ensures that the total number of lymphocytes in the periphery remains relatively constant. Mutations in PTPN22 confer an increased risk of developing autoimmune diseases; however, the precise function of PTPN22 and how mutations contribute to autoimmunity remain controversial. Loss-of-function mutations in PTPN22 are associated with increased numbers of effector T cells and autoreactive B cells in humans and mice; however, the complete absence of PTPN22 in mice ...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Brownlie RJ, Miosge LA, Vassilakos D, Svensson LM, Cope A, Zamoyska R Tags: Sci Signal Source Type: research
Cdc42 oscillations in yeasts.
Abstract A fundamental problem in cell biology is how cells define one or several discrete sites of polarity. Through mechanisms involving positive and negative feedback, the small Rho-family guanosine triphosphatase Cdc42 breaks symmetry in round budding yeast cells to define a single site of polarized cell growth. However, it is not clear how cells can define multiple sites of polarization concurrently. We discuss a study in which rod-shaped fission yeast cells, which naturally polarize growth at their two cell ends, exhibited oscillations of Cdc42 activity between these sites. We compare these findings with simi...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Bendezú FO, Martin SG Tags: Sci Signal Source Type: research
SCF-Mediated Degradation of p100 (NF-κB2): Mechanisms and Relevance in Multiple Myeloma.
Abstract On the basis of differential analysis of affinity purifications by mass spectrometry, we identified the nuclear factor κB (NF-κB) protein p100 (NF-κB2) as an interactor of the F-box protein FBXW7α. The NF-κB pathway is important for cell growth, differentiation, and survival. p100, which shuttles between the cytoplasm and nucleus, functions as the primary inhibitor of the noncanonical NF-κB pathway by sequestering NF-κB heterodimers in the cytoplasm. In the absence of NF-κB stimulation, the nuclear pool of p100 is constitutively targeted for degradation by FBXW7α, which recognizes a conserved moti...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Busino L, Millman SE, Pagano M Tags: Sci Signal Source Type: research
RNF4-Dependent Hybrid SUMO-Ubiquitin Chains Are Signals for RAP80 and Thereby Mediate the Recruitment of BRCA1 to Sites of DNA Damage.
Abstract The DNA repair function of the breast cancer susceptibility protein BRCA1 depends in part on its interaction with RAP80, which targets BRCA1 to DNA double-strand breaks (DSBs) through recognition of K63-linked polyubiquitin chains. The localization of BRCA1 to DSBs also requires sumoylation. We demonstrated that, in addition to having ubiquitin-interacting motifs, RAP80 also contains a SUMO-interacting motif (SIM) that is critical for recruitment to DSBs. In combination with the ubiquitin-binding activity of RAP80, this SIM enabled RAP80 to bind with nanomolar affinity to hybrid chains consisting of ubiqui...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Guzzo CM, Berndsen CE, Zhu J, Gupta V, Datta A, Greenberg RA, Wolberger C, Matunis MJ Tags: Sci Signal Source Type: research
G Protein-Coupled Receptor-Mediated Activation of p110β by Gβγ Is Required for Cellular Transformation and Invasiveness.
Abstract Synergistic activation by heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors (GPCRs) and receptor tyrosine kinases distinguishes p110β from other class IA phosphoinositide 3-kinases (PI3Ks). Activation of p110β is specifically implicated in various physiological and pathophysiological processes, such as the growth of tumors deficient in phosphatase and tensin homolog deleted from chromosome 10 (PTEN). To determine the specific contribution of GPCR signaling to p110β-dependent functions, we identified the site in p110β that binds to the Gβγ subunit of G proteins. Mutation ...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Dbouk HA, Vadas O, Shymanets A, Burke JE, Salamon RS, Khalil BD, Barrett MO, Waldo GL, Surve C, Hsueh C, Perisic O, Harteneck C, Shepherd PR, Harden TK, Smrcka AV, Taussig R, Bresnick AR, Nürnberg B, Williams RL, Backer JM Tags: Sci Signal Source Type: research
Comment on "epidermal growth factor receptor is essential for toll-like receptor 3 signaling".
Abstract Epidermal growth factor receptor (EGFR) and mammalian target of rapamycin (mTOR) play important roles in tumor growth, which has stimulated efforts toward the design of targeted cancer therapeutics that inhibit their function. A growing body of literature indicates that EGFR and mTOR are also essential to support a functional innate immune response. Hence, although combination therapies that block both EGFR and mTOR may have improved activity against tumors, they may also place patients at risk of fulminant infections. We discuss data supporting this hypothesis. PMID: 23233526 [PubMed - in process]
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Burtness B, Marur S, Bauman JE, Golemis EA, Mehra R, Cohen SJ Tags: Sci Signal Source Type: research
Celebrating 30 years of wnt signaling.
Abstract Wnt signal transduction is crucial for embryonic development and tissue homeostasis in multicellular animals. Hyperactivation of the Wnt pathway drives tumor formation, yet activation of the Wnt pathway in stem cells holds great promise for injury repair and regeneration. Between 27 June and 1 July 2012, scientists from all over the globe gathered in the beachfront town of Egmond aan Zee in the Netherlands to celebrate the 30th anniversary of this blossoming and exciting field. The latest advances and breakthroughs were discussed at the aptly named European Molecular Biology Organization conference 30 Year...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Verkaar F, Cadigan KM, van Amerongen R Tags: Sci Signal Source Type: research
TIM Family Proteins Promote the Lysosomal Degradation of the Nuclear Receptor NUR77.
Abstract T cell immunoglobulin and mucin domain (TIM) proteins are cell-surface signaling receptors in T cells and scavenger receptors in antigen-presenting cells and kidney tubular epithelia. Here, we demonstrated a function for TIM proteins in mediating the degradation of NUR77, a nuclear receptor implicated in apoptosis and cell survival. TIM proteins interacted with and mediated the lysosomal degradation of NUR77 in a phosphoinositide 3-kinase-dependent pathway. We also showed dynamic cycling of TIM-1 to and from the cell surface through clathrin-dependent constitutive endocytosis. Blocking this process or muta...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Balasubramanian S, Kota SK, Kuchroo VK, Humphreys BD, Strom TB Tags: Sci Signal Source Type: research
Mechanism of stretch-induced activation of the mechanotransducer zyxin in vascular cells.
Abstract Vascular cells respond to supraphysiological amounts of stretch with a characteristic phenotypic change that results in dysfunctional remodeling of the affected arteries. Although the pathophysiological consequences of stretch-induced signaling are well characterized, the mechanism of mechanotransduction is unclear. We focused on the mechanotransducer zyxin, which translocates to the nucleus to drive gene expression in response to stretch. In cultured human endothelial cells and perfused femoral arteries isolated from wild-type and several knockout mouse strains, we characterized a multistep signaling path...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Suresh Babu S, Wojtowicz A, Freichel M, Birnbaumer L, Hecker M, Cattaruzza M Tags: Sci Signal Source Type: research
IGFBP7 Binds to the IGF-1 Receptor and Blocks Its Activation by Insulin-Like Growth Factors.
Abstract Insulin-like growth factor-binding protein 7 (IGFBP7) is a secreted factor that suppresses growth, and the abundance of IGFBP7 inversely correlates with tumor progression. Here, we showed that pretreatment of normal and breast cancer cells with IGFBP7 interfered with the activation and internalization of insulin-like growth factor 1 receptor (IGF1R) in response to insulin-like growth factors 1 and 2 (IGF-1/2), resulting in the accumulation of inactive IGF1R on the cell surface and blockade of downstream phosphatidylinositol 3-kinase (PI3K)-AKT signaling. Binding of IGFBP7 and IGF-1 to IGF1R was mutually ex...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Evdokimova V, Tognon CE, Benatar T, Yang W, Krutikov K, Pollak M, Sorensen PH, Seth A Tags: Sci Signal Source Type: research
c-FLIP Maintains Tissue Homeostasis by Preventing Apoptosis and Programmed Necrosis.
Abstract As a catalytically inactive homolog of caspase-8, a proapoptotic initiator caspase, c-FLIP blocks apoptosis by binding to and inhibiting caspase-8. The transcription factor nuclear factor κB (NF-κB) plays a pivotal role in maintaining the homeostasis of the intestine and the liver by preventing death receptor-induced apoptosis, and c-FLIP plays a role in the NF-κB-dependent protection of cells from death receptor signaling. Because c-Flip-deficient mice die in utero, we generated conditional c-Flip-deficient mice to investigate the contribution of c-FLIP to homeostasis of the intestine and the liver at ...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Piao X, Komazawa-Sakon S, Nishina T, Koike M, Piao JH, Ehlken H, Kurihara H, Hara M, Van Rooijen N, Schütz G, Ohmuraya M, Uchiyama Y, Yagita H, Okumura K, He YW, Nakano H Tags: Sci Signal Source Type: research
A CC-SAM, for Coiled Coil-Sterile α Motif, Domain Targets the Scaffold KSR-1 to Specific Sites in the Plasma Membrane.
Abstract Kinase suppressor of Ras-1 (KSR-1) is an essential scaffolding protein that coordinates the assembly of the mitogen-activated protein kinase (MAPK) module, consisting of the MAPK kinase kinase Raf, the MAPK kinase MEK (mitogen-activated or extracellular signal-regulated protein kinase kinase), and the MAPK ERK (extracellular signal-regulated kinase) to facilitate activation of MEK and thus ERK. Although KSR-1 is targeted to the cell membrane in part by its atypical C1 domain, which binds to phospholipids, other domains may be involved. We identified another domain in KSR-1 that we termed CC-SAM, which is c...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Koveal D, Schuh-Nuhfer N, Ritt D, Page R, Morrison DK, Peti W Tags: Sci Signal Source Type: research
Extracellular phosphorylation and phosphorylated proteins: not just curiosities but physiologically important.
Abstract Mining of the literature and high-throughput mass spectrometry data from both healthy and diseased tissues and from body fluids reveals evidence that various extracellular proteins can exist in phosphorylated states. Extracellular kinases and phosphatases (ectokinases and ectophosphatases) are active in extracellular spaces during times of sufficiently high concentrations of adenosine triphosphate. There is evidence for a role of extracellular phosphorylation in various physiological functions, including blood coagulation, immune cell activation, and the formation of neuronal networks. Ectokinase activity ...
Source: Science Signaling - December 26, 2012 Category: Biomedical Science Authors: Yalak G, Vogel V Tags: Sci Signal Source Type: research
Proceedings of the National Academy of Sciences USA 109: 21319-21324 (12-26-12)
Proceedings of the National Academy of Sciences USA 109: 21319-21324 Reelin is a target of polyglutamine expanded ataxin-7 in human spinocerebellar ataxia type 7 (SCA7) astrocytes Shaun D. McCullough, Xiaojiang Xu, Sharon Y. R. Dent, Stefan Bekiranov, Robert G. Roederc … More »
Source: The Rockefeller University Newswire - December 26, 2012 Category: Biomedical Science Authors: pubaff Tags: Research Update Source Type: news
Aluminum may mediate Alzheimer’s disease through liver toxicity, with aberrant hepatic synthesis of ceruloplasmin and ATPase7B, the resultant excess free copper causing brain oxidation, beta-amyloid aggregation and Alzheimer disease
A likely pathophysiologic mechanism of Alzheimer disease (AD) is aluminum (Al) toxicity to the liver, with resulting aberrant hepatic copper (Cu) homeostasis causing brain Cu toxicity.
Source: Medical Hypotheses - December 26, 2012 Category: Biomedical Science Authors: Steven Brenner Tags: Correspondence Source Type: research
Angiotensin receptor blockers for bipolar disorder
Abstract: Studies have suggested that the brain renin angiotensin system (RAS) regulates cerebral flow, autonomic and hormonal systems, stress, innate immune response and behavior, being implicated in several brain disorders such as major depression, Parkinson’s and Alzheimer’s disease. The angiotensin II receptor subtype 1 (AT1R) is distributed in brain regions responsible for the control of stress response through peripheral and central sympathetic hyperactivation as well as in the hypothalamic paraventricular region, areas known for the release of several neurotransmitters related to inflammatory response facilitati...
Source: Medical Hypotheses - December 26, 2012 Category: Biomedical Science Authors: Ana Isabelle de Góis Queiroz, Camila Dantas Medeiros, Bruna Mara Machado Ribeiro, David Freitas de Lucena, Danielle Silveira Macêdo Tags: Articles Source Type: research
Antipsychotic medications, glutamate, and cell death: A hidden, but common medication side effect?
Abstract: We hypothesize the interaction between antipsychotic medications and regulation of extracellular glutamate which has gone largely unnoticed in the medical community has significant clinical importance. Typical antipsychotic medications such as haloperidol elevate extracellular glutamate because they exert antagonist effects on dopamine D2 and serotonin 5HT1A receptors. In contrast, serotonin 5HT2A receptor antagonists inhibit glutamate release. Glutamate is potentially excitotoxic through effects on ionotropic receptor channels and may exert synergistic effects with other neurotoxic pathways. In contrast to typic...
Source: Medical Hypotheses - December 26, 2012 Category: Biomedical Science Authors: Amanda M. Isom, Gary A. Gudelsky, Stephen C. Benoit, Neil M. Richtand Tags: Articles Source Type: research
Epigenetics as a new therapeutic target for postoperative cognitive dysfunction
Abstract: Persistent memory and learning disabilities may occur postoperatively and may be related to neurodegenerative processes. Epigenetic dysregulation has been implicated to abnormal brain function and neurodegenerative diseases. Some risk factors contributing to postoperative cognitive disorder (POCD) have been identified, including exposure to general anesthesia, hypotension, hypoxia, psychoactive drugs, hippocampal inflammation induced by the surgical intervention, etc. The current evidence supports these risk factors might induce epigenetic dysfunction in the brain. It is possible that epigenetic regulation might ...
Source: Medical Hypotheses - December 26, 2012 Category: Biomedical Science Authors: Yun Wang, Zhijun Chen, Yujie Zhao, Rong Shi, Yue Wang, Jie Xu, Anshi Wu, Roger A. Johns, Yun Yue Tags: Articles Source Type: research
Using electroacupuncture at acupoints to predict the efficacy of hippocampal high-frequency electrical stimulation in pharmacoresistant temporal lobe epilepsy patients
Abstract: Hippocampal high-frequency electrical stimulation (HFS) shows long-term efficiency in some pharmacoresistant temporal lobe epilepsy patients. However, the success of the procedure varies from patient to patient and neither neurologists nor neurosurgeons are currently unable to pre-operatively predict which patients will respond to the stimulation. Just like electrical stimulation of the hippocampus in the brain, electroacupuncture (EA) at acupoints involves electrical stimulation and is also efficient in treating epilepsy. However, the stimulation targets are acupoints, which are located outside of the brain, and...
Source: Medical Hypotheses - December 26, 2012 Category: Biomedical Science Authors: Fan-Gang Meng, C. Chris Kao, Hong Zhang, Ning Chen, Yan Ge, Chong Liu, Jian-Guo Zhang Tags: Articles Source Type: research
Dietary copper: A novel predisposing factor for oral submucous fibrosis?
Abstract: Oral submucous fibrosis (OSMF) is known devastating disorder commonly seen in South Asian developing countries. It is directly linked to areca nut chewing and the contents of areca are subjected to multitude of investigations. Among all the contents of areca nut, the copper element has been extensively studied. Most of the published studies have validated its association with OSMF because of its local action. In this paper we postulate a novel biological pathway through which copper is thought to predispose oral mucosa to OSMF. The hypothesis is instructive in explaining various unexplored aspects of the disease.
Source: Medical Hypotheses - December 26, 2012 Category: Biomedical Science Authors: Gururaj Arakeri, Peter A. Brennan Tags: Articles Source Type: research
IBS, NERD and functional dyspepsia are immuno–neuronal disorders of mucosal cytokine imbalances clinically reversible with high potency sucralfate
Abstract: Irritable bowel syndrome (IBS), non-erosive reflux disorder (NERD), and functional dyspepsia (FD) are best classified as immuno–neuronal disorders of the mucosa or functional mucosal syndromes (FMS). Each appears to be clinically reversible using high potency sucralfate (HPS). In FMS of the GI tract, postprandial nausea, altered motility, discordant peristalsis, vomiting, diarrhea, and hyperalgesia are the clinical expressions of a mucosal imbalance between pro-inflammatory cytokines of up-regulated intra-epithelial lymphocytes (IELs) and feedback anti-inflammatory cytokines tasked with moderating the antigenic...
Source: Medical Hypotheses - December 26, 2012 Category: Biomedical Science Authors: Ricky W. McCullough Tags: Articles Source Type: research
Does histology predict the clinical outcome after lumbar intervertebral disc herniation: No
Discussion and conclusions: A reliable prediction of the success of treatment, including patient outcome, cannot be made on the basis of the present histological criteria. The hypothesis must therefore be rejected.
Source: Medical Hypotheses - December 26, 2012 Category: Biomedical Science Authors: Dirk Winkler, Niels Hammer, Johannes Gossner, Ralf Schober, Heinz-Ekkehard Vitzthum, Jürgen Meixensberger Tags: Articles Source Type: research
Confined compression of collagen hydrogels
This study suggests that confined compression, together with biphasic theory, is a suitable technique for assessing the mechanical properties of collagen hydrogels.
Source: Journal of Biomechanics - December 26, 2012 Category: Biomedical Science Authors: Grahame A. Busby, M. Helen Grant, Simon P. MacKay, Philip E. Riches Tags: Papers Source Type: research
Development of calcium phosphate cement for the augmentation of traumatically fractured porcine specimens using vertebroplasty
Abstract: The study aim was to develop and apply an experimental technique to determine the biomechanical effect of polymethylmethacrylate (PMMA) and calcium phosphate (CaP) cement on the stiffness and strength of augmented vertebrae following traumatic fracture. Twelve burst type fractures were generated in porcine three-vertebra segments. The specimens were randomly split into two groups (n=6), imaged using microCT and tested under axial loading. The two groups of fractured specimens underwent a vertebroplasty procedure, one group was augmented with CaP cement designed and developed at Queen's University Belfast. The oth...
Source: Journal of Biomechanics - December 26, 2012 Category: Biomedical Science Authors: Sami M. Tarsuslugil, Rochelle M. O’Hara, Nicholas J. Dunne, Fraser J. Buchanan, John F. Orr, David C. Barton, Ruth K. Wilcox Tags: Papers Source Type: research
Fractionation of 50kGy electron beam irradiation: Effects on biomechanics of human flexor digitorum superficialis tendons treated with ascorbate
Abstract: The electron beam (Ebeam) irradiation has begun to be considered as an efficient alternative to gamma irradiation in the sterilization of allografts in the reconstruction of anterior cruciate ligament. The purpose of this study was to evaluate the biomechanical properties of human tendons after exposure to electron beam and free radical scavenger ascorbate. Forty human flexor digitorum superficialis tendons were prepared from five fresh cadavers and divided randomly into four groups: A, fresh (0kGy); B, 50kGy Ebeam irradiation; C, fractionated 50kGy Ebeam irradiation; D, fractionated 50kGy Ebeam on ascorbate-trea...
Source: Journal of Biomechanics - December 26, 2012 Category: Biomedical Science Authors: Wei Wei, Yujie Liu, Xu Yang, Shaoqi Tian, Chao Liu, Yang Zhang, Zhaoning Xu, Baiqiang Hu, Zhen Tian, Kang Sun Tags: Papers Source Type: research
Abstract: Neurodegenerative diseases are associated with neuronal inclusions, comprised of protein aggregates. In Alzheimer’s Disease (AD) and Lewy Body Disease (LBD) such lesions are distributed in a hierarchical retrograde transynaptic spatial pattern. This implies a retrograde transynaptic temporal propagation as well. There can be few explanations for this other than infectious agents (prions and viruses). This suggests that AD and LBD (at least) may have infectious origins.Transynaptic infiltration of the CNS along cranial nerve or other major projections, by one or more infectious agents has important implications....
Source: Medical Hypotheses - December 26, 2012 Category: Biomedical Science Authors: Donald R. Royall Tags: Articles Source Type: research
Integrating qPLM and biomechanical test data with an anisotropic fiber distribution model and predictions of TGF-[Formula: see text]1 and IGF-1 regulation of articular cartilage fiber modulus.
Abstract A continuum mixture model with distinct collagen (COL) and glycosaminoglycan elastic constituents was developed for the solid matrix of immature bovine articular cartilage. A continuous COL fiber volume fraction distribution function and a true COL fiber elastic modulus ([Formula: see text] were used. Quantitative polarized light microscopy (qPLM) methods were developed to account for the relatively high cell density of immature articular cartilage and used with a novel algorithm that constructs a 3D distribution function from 2D qPLM data. For specimens untreated and cultured in vitro, most model paramete...
Source: Biomechanics and Modeling in Mechanobiology - December 25, 2012 Category: Biomedical Science Authors: Stender ME, Raub CB, Yamauchi KA, Shirazi R, Vena P, Sah RL, Hazelwood SJ, Klisch SM Tags: Biomech Model Mechanobiol Source Type: research
series:Advances in Experimental Medicine and BiologyThe genomic ‘golden age’ has delivered the sequence of numerous novel genes while leaving us with many unanswered questions about their function. This is particularly true for gene families as, often, members are annotated based on homology rather than function. The tripartite motif family belonged to this category, although, during the last few years, the field boosted an important wealth of ...
Source: Springer Biomedical Sciences titles - December 24, 2012 Category: Biomedical Science Tags: Biomedicine (general) Source Type: news
Stem Cells and Cancer Stem Cells, Volume 9
Therapeutic Applications in Disease and Injuryseries:Stem Cells and Cancer Stem CellsThis fresh addition to the rapidly expanding Springer series on stem cells represents an additional forward step in our understanding of the causes, diagnosis, and cell-related therapies of major human diseases as well as debilitating injuries to human tissue and organs. Showcasing the work of more than 80 contributors from 13 nations, it offers an unrivalled breadth of differing perspectives ...
Source: Springer Biomedical Sciences titles - December 23, 2012 Category: Biomedical Science Tags: Cancer Research Source Type: news
Rehabilitation After Myocardial Infarction Trial (RAMIT)
The Authors' reply The editorials on the multicentre trial of rehabilitation following acute myocardial infarction1 call for comment. The money did not run out, as Wood2 asserts. The major portion of the grant was returned to NHS R&D. Early closure was requested primarily because of the emerging ‘national service framework’ (NSF, a ‘guidance note’)3 (Department of Health, personal communication). The ‘emerging NSF’ could have led to reducing the patient recruitment rate;4 although many more centres were in the process of joining.1 In the interests of medical science, patient care and...
Source: Heart - December 23, 2012 Category: Cardiology Authors: West, R. R., Jones, D. A., Henderson, A. H. Tags: PostScript Source Type: research
Tumors of the Central Nervous System, Volume 10
Pineal, Pituitary, and Spinal Tumorsseries:Tumors of the Central Nervous SystemAdding to a vitally important cycle of publications covering the latest research developments in our understanding of neoplasms affecting the human central nervous system, this edition focuses on numerous aspects of pineal, pituitary, and spinal tumors. As with the previous volumes in the series, this latest work addresses a central imperative in cancer research—the need to standardize ...
Source: Springer Biomedical Sciences titles - December 22, 2012 Category: Biomedical Science Tags: Cancer Research Source Type: news
The Journal of Biomechanics: Evolving with Electronic Publishing
With the first issue of 2013, we are pleased to announce a number of changes to the Journal of Biomechanics that we hope will enhance the journal’s content, impact, and scope even further. Many of these changes are possible only now with the advent and tremendous growth of electronic publishing.
Source: Journal of Biomechanics - December 22, 2012 Category: Biomedical Science Authors: Farshid Guilak Tags: Editorial Source Type: research
A heartfelt response: new thyroid hormone–sensitive neurons in the hypothalamus
Thyroid hormone is a well-known regulator of metabolic and cardiovascular functions, and signaling through thyroid receptors has differential effects on cells depending on the receptor isoform that they express. In this issue of the JCI, Mittag et al. provide evidence that thyroid hormone receptors are essential for the formation of a population of parvalbuminergic neurons in the anterior hypothalamus, linking, for the first time, impaired thyroid hormone signaling during development to cellular deficits in the hypothalamus. Since this newly discovered cell group is predicted to play a role in regulating cardiovascular fun...
Source: Journal of Clinical Investigation - December 22, 2012 Category: Biomedical Science Authors: Douglas Forrest, Jürgen Wess Source Type: research
The benefits of restraint: a pivotal role for IL-13 in hepatic glucose homeostasis
In response to feeding, insulin promotes the uptake of sugar in peripheral tissues and suppresses the production of sugar, a process called gluconeogenesis, in the liver. Recent research has shown that chronic inflammation promotes insulin resistance, and in turn, chronically high glucose levels can drive inflammation. In this issue of the JCI, Stanya et al. investigate the connection between inflammation and glucose homeostasis by analyzing the effect of the antiinflammatory cytokine IL-13. Their results suggest that IL-13 plays an unexpected role in the regulation of glucose homeostasis by modulating gluconeogenesis and ...
Source: Journal of Clinical Investigation - December 22, 2012 Category: Biomedical Science Authors: Mariana Verdelho Machado, Yiping Yang, Anna Mae Diehl Source Type: research
Iron deficiency and Helicobacter pylori–induced gastric cancer: too little, too bad
Clinical vignette: A 38-year-old man consults you in the GI clinic because of frequent episodes of epigastric pain, nausea, and tiredness. His blood count shows signs of mild iron deficiency anemia. Upper GI endoscopy was normal, but antral and corpus biopsy specimens show evidence of gastric atrophy and Helicobacter pylori infection. Colonoscopy and capsule endoscopy showed no evidence of lesions in the large or small bowel. He receives a standard one-week course eradication therapy consisting of a proton pump inhibitor (PPI), amoxicillin, and clarithromycin. His symptoms improve, but his infection persists and he remains...
Source: Journal of Clinical Investigation - December 22, 2012 Category: Biomedical Science Authors: Emad M. El-Omar Source Type: research
Prognostically relevant gene signatures of high-grade serous ovarian carcinoma
Because of the high risk of recurrence in high-grade serous ovarian carcinoma (HGS-OvCa), the development of outcome predictors could be valuable for patient stratification. Using the catalog of The Cancer Genome Atlas (TCGA), we developed subtype and survival gene expression signatures, which, when combined, provide a prognostic model of HGS-OvCa classification, named “Classification of Ovarian Cancer” (CLOVAR). We validated CLOVAR on an independent dataset consisting of 879 HGS-OvCa expression profiles. The worst outcome group, accounting for 23% of all cases, was associated with a median survival of 23 m...
Source: Journal of Clinical Investigation - December 22, 2012 Category: Biomedical Science Authors: Roel G.W. Verhaak, Pablo Tamayo, Ji-Yeon Yang, Diana Hubbard, Hailei Zhang, Chad J. Creighton, Sian Fereday, Michael Lawrence, Scott L. Carter, Craig H. Mermel, Aleksandar D. Kostic, Dariush Etemadmoghadam, Gordon Saksena, Kristian Cibulskis, Sekhar Durai Source Type: research