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Dysferlinopathy is a genetic human disease caused by mutations in the gene that encodes the dysferlin protein (DYSF). Dysferlin is believed to play a relevant role in cell membrane repair. However, in dysferlin-deficient (blAJ) mice (a model of dysferlinopathies) the recovery of the membrane resealing function by means of the expression of a mini-dysferlin does not arrest progressive muscular damage, suggesting the participation of other unknown pathogenic mechanisms. Here, we show that proteins called connexins 39, 43 and 45 (Cx39, Cx43 and Cx45, respectively) are expressed by blAJ myofibers and form functional hemichannels (Cx HCs) in the sarcolemma. At rest, Cx HCs increased the sarcolemma permeability to small molecules and the intracellular Ca2+ signal. In addition, skeletal muscles of blAJ mice showed lipid accumulation and lack of dysferlin immunoreactivity. As sign of extensive damage and atrophy, muscles of blAJ mice presented elevated numbers of myofibers with internal nuclei, increased number of myofibers with reduced cross-sectional area and elevated creatine kinase activity in serum. In agreement with the extense muscle damage, mice also showed significantly low motor performance. We generated blAJ mice with myofibers deficient in Cx43 and Cx45 expression and found that all above muscle and systemic alterations were absent, indicating that these two Cxs play a critical role in a novel pathogenic mechanism of dysfernolophaties, which is discussed herein. Therefore, Cx HCs could constitute an attractive target for pharmacologic treatment of dyferlinopathies. V.BACKGROUND The folding of the human cortex complicates extraction of position information and recognition of patterns across the cortical surface. NEW METHOD As straight lines correspond better to our intuitions in spatial orientation, we developed an approach for imposing Cartesian grids on portions of the cortical surface, which can then be represented in a rectangular matrix. These functions have been implemented in the Cgrid (Cartesian Geometric Representation with Isometric Dimensions) toolbox. Cgrids can be generated based on regions of interest, or combinations thereof, according to any one of the Freesurfer's annotation schemes. RESULTS The toolbox was evaluated using the surface reconstructions of T1-weighted images of 30 subjects, and 17 different Cgrids that in combination covered nearly the entire surface area of the brain. The vast majority of Cgrids (90.4 %) could be generated without issues. COMPARISON WITH EXISTING METHOD(S) The toolbox facilitates spatial orientation and pattern recognition, in addition to allowing detailed comparison between the left and right hemisphere, and bringing existing volumetric tools to bear on surface-based data. The output of the toolbox is fully compatible with most existing fMRI/MRI analyses packages, and is immediately suitable as input for second level analysis. CHIR-124 CONCLUSIONS The toolbox has the potential for broad applicability, especially when ease of data handling and representation are critical factors. The toolbox can be downloaded from https//github.com/mathijsraemaekers/Cgrid-toolbox. V.BACKGROUND Integrins are the major cell adhesion receptors expressed in almost all cell types connecting the extracellular matrix with cell cytoskeletons and transducing bi-directional signals across cell membranes. In the central nervous system (CNS), integrins are pivotal for CNS cell migration, differentiation, neurite outgrowth and synaptogenesis in both physiological and pathological conditions. Here we studied the effect of different integrin biding peptides for growth and development of primary cortical neurons in vitro. NEW METHOD Rat primary cortical neurons were cultured in an integrin-binding array platform, which contains immobilized varying short synthetic peptides that bind to 16 individual types of integrin on a 48-well cell culture plate. After cultured for 7 days, cells were fixed and processed for immunostaining with neuronal markers. The overall neuronal growth and neurite outgrowths were quantified. RESULTS We found that binding peptides for integrin αvβ8, α5β1 and α3β1 particularly the former two provided superior condition for neuronal growth, survival and maturation. Moreover, optimal neurite outgrowth was observed when neurons were cultured in 3-dimension using injectable hydrogel along with binding peptide for αvβ8 or α5β1 integrins. COMPARISON WITH EXISTING METHOD For primary neuronal culture, poly-D-lysine coating is conventional method to support cell attachment. Our study has demonstrated that selected integrin binding peptides provide greater support for the growth of cultured primary neurons. CONCLUSION These data suggest that integrin αvβ8 and α5β1 are conducive for survival, growth and maturation of primary cortical neurons. This information could be utilized in designing combinational biomaterial and cell-based therapy for neural regeneration following brain injury. Autologous grafts are the current gold standard of care for coronary artery bypass graft surgeries, but are limited by availability and plagued by high failure rates. Similarly, tissue engineering approaches to small diameter vascular grafts using naturally derived and synthetic materials fall short, largely due to inappropriate mechanical properties. Alternatively, decellularized extracellular matrix from tissue is biocompatible and has comparable strength to vessels, while poly(propylene fumarate) (PPF) has shown promising results for vascular grafts. This study investigates the integration of decellularized pericardial extracellular matrix (dECM) and PPF to create a biohybrid scaffold (dECM+PPF) suitable for use as a small diameter vascular graft. Our method to decellularize the ECM was efficient at removing DNA content and donor variability, while preserving protein composition. PPF was characterized and added to the dECM, where it acted to preserve the dECM against degradative effects of collagenase without disturbing the material's overall mechanics. A transport study showed that diffusion occurs across dECM+PPF without any effect from collagenase. dECM+PPF matched the modulus of human coronary arteries and saphenous veins. dECM+PPF vascular grafts demonstrated ample circumferential stress, burst pressure, and suture retention strength to survive in vivo. An in vivo study showed re-endothelialization and tissue growth. Overall, the dECM+PPF biohybrid presents a robust solution to overcome the limitations of current methods of treatment for small diameter vascular grafts.

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