Neurology eJournal最新文献

{"title":"Pelvic Floor Muscle Function Recovery Using Biofabricated Tissue Constructs with Neuromuscular Junctions","authors":"J. Kim, I. Ko, M. Jeon, Ickhee Kim, Margaret Maria Vanschaayk, A. Atala, J. Yoo","doi":"10.2139/ssrn.3674054","DOIUrl":"https://doi.org/10.2139/ssrn.3674054","url":null,"abstract":"Damages in pelvic floor muscles often cause dysfunction of the entire pelvic urogenital system, which is clinically challenging. A bioengineered skeletal muscle construct that mimics structural and functional characteristics of native skeletal muscle could provide a therapeutic option to restore normal muscle function. However, most of the current bioengineered muscle constructs are unable to provide timely innervation necessary for successful grafting and functional recovery. We previously have demonstrated that post-synaptic acetylcholine receptors (AChR) clusters can be pre-formed on cultured skeletal muscle myofibers with agrin treatment and suggested that implantation of AChR clusters containing myofibers could accelerate innervation and recovery of muscle function. In this study, we develop a 3-dimensional (3D) bioprinted human skeletal muscle construct, consisting of multi-layers bundles with aligned and AChR clusters pre-formed human myofibers, and investigate the effect of pre-formed AChR clusters in bioprinted skeletal muscle constructs and innervation efficiency in vivo. Agrin treatment successfully pre-formed functional AChR clusters on the bioprinted muscle constructs in vitro that increased neuromuscular junction (NMJ) formation in vivo in a transposed nerve implantation model in rats. In a rat model of pelvic floor muscle injury, implantation of skeletal muscle constructs containing the pre-formed AChR clusters resulted in functional muscle reconstruction with accelerated construct innervation. This approach may provide a therapeutic solution to the many challenges associated with pelvic floor reconstruction resulting from the lack of suitable bioengineered tissue for efficient innervation and muscle function restoration.","PeriodicalId":134810,"journal":{"name":"Neurology eJournal","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133758031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cortical Oscillatory Modular Processing Electrical Sources","authors":"A. D. da Rocha","doi":"10.2139/ssrn.3413566","DOIUrl":"https://doi.org/10.2139/ssrn.3413566","url":null,"abstract":"The brain is a distributed network (DIPS) of multiple agents specialized in solving specific tasks and joining efforts to handle complex cognitive activities as a time of efficient cortical columns assemblies (CA). The column distinct cortical layers generate different slow and fast currents that sum up into a total columnar oscillatory current that is low and noisy. The increment of the input activity triggered by sensory stimulation or internal activity created by reasoning, entrains not only the intrinsic activity of each column but also the activity of a defined number of neighboring columns. This entrainment increases the value of the different columnar that sum up into a larger current whose value heavily depends on the number of the entrained columns. The input and oscillatory activity of all cortical areas recruited to support a cognitive task is organized into a Cortical Oscillatory Modular Processing (COMP) that generates a event related activity that may be identified in the EEG recorded while the individual is solving the task. These are segmented into four waves of Wi components. Here, the sLORETA software was used to identify he input and oscillatory sources activated by different cognitive processing. The analysis of the temporal and spatial distribution of these sources revealed that and activity contributes to generate the distinct Wi components of the distinct supporting the cortical modular processing of any cognitive task. The source movement during the distinct entrains and integrates the sequential cortical processing COMP to update and unify the cognitive activity related to a task to be solved.","PeriodicalId":134810,"journal":{"name":"Neurology eJournal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128927312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biomimetic Injectable 3D Hydrogels with Aligned Topography for Neural Tissue Engineering","authors":"Liza J. Severs, Lindsay N. Cates, Dane M Dewees, Riana T. Hoagland, P. Horner, C. Hofstetter, Zin Z. Khaing","doi":"10.2139/ssrn.3399184","DOIUrl":"https://doi.org/10.2139/ssrn.3399184","url":null,"abstract":"Spinal cord trauma leads to destruction of the highly organized cytoarchitecture that carries information along the axis of the spinal column. Currently, there are no clinically accepted strategies that can help regenerate severed axons after spinal cord injury. Experimental neuroregenerative efforts include the creation of optimal biomaterials with aligned topography to support enhanced neuronal regeneration. Hydrogels are soft biomaterials with high water content that are widely used as scaffolds to interface with the central nervous system (CNS). Current available methods to create topography within the 3D amorphous hydrogels are typically complex. Here we examine a simple and reproducible method that results in consistently aligned fibrils within 3D matrices using thermally gelling biomimetic polymers that are compatible with neuronal cells. A collagen type I (Col)-based thermally gelling hydrogel system was used in combination with two other native extracellular matrix proteins: laminin I (LN), and hyaluronic acid (HA). Gelling kinetics for all gel types (Col, Col LN, Col HA) were examined, and we found that all three combinations of polymer formed consistent gels at 37°C. Col solution was faster to form gels (17 min), while Col LN and Col HA took longer (~22 minutes). A method of aspiration and ejection was used to produce Col-based hydrogels containing aligned fibrils. Gels were then examined using scanning electron microscopy (SEM). SEM images confirmed successful alignment in all gel types, and the size of fibers was consistent with reported values for collagen (~250 nm in diameter). We found that embryonic spinal cord neurons survive and produce processes aligned to collagen fibrils after 14 days <i>in vitro</i>. Next, we investigated the functionality of aligned and non-aligned Col hydrogels implanted acutely after a contusion type spinal cord injury to the thoracic spinal cord at T7/T8. Pan neuronal antibody-positive fibrils were found within all implants, aligned hydrogels supported neurite growth along the parallel direction of the implanted hydrogels. Our data indicate that thermally gelling biomimetic hydrogels can produce aligned matrices by a method of aspiration and ejection. The material composition and process of aligning hydrogels outlined here presents a novel platform for regenerative therapies for the CNS that is compatible with the survival and growth of neuronal cells <i>in vitro</i> and <i>in vivo</i>.","PeriodicalId":134810,"journal":{"name":"Neurology eJournal","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128287950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}