The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
S. Randal Voss - One of the best experts on this subject based on the ideXlab platform.
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Towards comparative analyses of salamander limb regeneration.
Journal of Experimental Zoology Part B: Molecular and Developmental Evolution, 2019Co-Authors: Varun B. Dwaraka, S. Randal VossAbstract:Among tetrapods, only salamanders can regenerate their limbs and tails throughout life. This amazing Regenerative Ability has attracted the attention of scientists for hundreds of years. Now that large, salamander genomes are beginning to be sequenced for the first time, omics tools and approaches can be used to integrate new perspectives into the study of tissue regeneration. Here we argue the need to move beyond the primary salamander models to investigate regeneration in other species. Salamanders at first glance come across as a phylogenetically conservative group that has not diverged greatly from their ancestors. While salamanders do present ancestral characteristics of basal tetrapods, including the Ability to regenerate limbs, data from fossils and data from studies that have tested for species differences suggest there may be considerable variation in how salamanders develop and regenerate their limbs. We review the case for expanded studies of salamander tissue regeneration and identify questions and approaches that are most likely to reveal commonalities and differences in regeneration among species. We also address challenges that confront such an initiative, some of which are regulatory and not scientific. The time is right to gain evolutionary perspective about mechanisms of tissue regeneration from comparative studies of salamander species.
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Revisiting the relationship between Regenerative Ability and aging
BMC biology, 2013Co-Authors: Ashley W. Seifert, S. Randal VossAbstract:Contrary to the longstanding view that newts (Notophthalamus viridescens), but not axolotls (Ambystoma mexicanum), can regenerate a lens, a recent report in BMC Biology by Panagiotis Tsonis and colleagues shows axolotls indeed possess this Ability during early larval stages. In contrast, they show that zebrafish never posses this Ability, even as embryos. This underscores the importance of comparing Regenerative Ability across species and reinforces the need to consider organ regeneration in the context of evolution, development, and aging.
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Early gene expression during natural spinal cord regeneration in the salamander Ambystoma mexicanum
Journal of Neurochemistry, 2006Co-Authors: James R. Monaghan, John A. Walker, Robert B. Page, Srikrishna Putta, Christopher K. Beachy, S. Randal VossAbstract:In contrast to mammals, salamanders have a remarkable Ability to regenerate their spinal cord and recover full movement and function after tail amputation. To identify genes that may be associated with this greater Regenerative Ability, we designed an oligonucleotide microarray and profiled early gene expression during natural spinal cord regeneration in Ambystoma mexicanum. We sampled tissue at five early time points after tail amputation and identified genes that registered significant changes in mRNA abundance during the first 7 days of regeneration. A list of 1036 statistically significant genes was identified. Additional statistical and fold change criteria were applied to identify a smaller list of 360 genes that were used to describe predominant expression patterns and gene functions. Our results show that a diverse injury response is activated in concert with extracellular matrix remodeling mechanisms during the early acute phase of natural spinal cord regeneration. We also report gene expression similarities and differences between our study and studies that have profiled gene expression after spinal cord injury in rat. Our study illustrates the utility of a salamander model for identifying genes and gene functions that may enhance Regenerative Ability in mammals.
James R. Monaghan - One of the best experts on this subject based on the ideXlab platform.
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Spinal Cord Regeneration in Amphibians: A Historical Perspective.
Developmental Neurobiology, 2019Co-Authors: Polina D. Freitas, Anastasia S. Yandulskaya, James R. MonaghanAbstract:In some vertebrates, a grave injury to the central nervous system (CNS) results in functional restoration, rather than in permanent incapacitation. Understanding how these animals mount a Regenerative response by activating resident CNS stem cell populations is of critical importance in Regenerative biology. Amphibians are of a particular interest in the field because the Regenerative Ability is present throughout life in urodele species, but in anuran species it is lost during development. Studying amphibians, who transition from a Regenerative to a nonRegenerative state, could give insight into the loss of Ability to recover from CNS damage in mammals. Here, we highlight the current knowledge of spinal cord regeneration across vertebrates and identify commonalities and differences in spinal cord regeneration between amphibians.
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Early gene expression during natural spinal cord regeneration in the salamander Ambystoma mexicanum
Journal of Neurochemistry, 2006Co-Authors: James R. Monaghan, John A. Walker, Robert B. Page, Srikrishna Putta, Christopher K. Beachy, S. Randal VossAbstract:In contrast to mammals, salamanders have a remarkable Ability to regenerate their spinal cord and recover full movement and function after tail amputation. To identify genes that may be associated with this greater Regenerative Ability, we designed an oligonucleotide microarray and profiled early gene expression during natural spinal cord regeneration in Ambystoma mexicanum. We sampled tissue at five early time points after tail amputation and identified genes that registered significant changes in mRNA abundance during the first 7 days of regeneration. A list of 1036 statistically significant genes was identified. Additional statistical and fold change criteria were applied to identify a smaller list of 360 genes that were used to describe predominant expression patterns and gene functions. Our results show that a diverse injury response is activated in concert with extracellular matrix remodeling mechanisms during the early acute phase of natural spinal cord regeneration. We also report gene expression similarities and differences between our study and studies that have profiled gene expression after spinal cord injury in rat. Our study illustrates the utility of a salamander model for identifying genes and gene functions that may enhance Regenerative Ability in mammals.
Lukas Brügger - One of the best experts on this subject based on the ideXlab platform.
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Autologous transplantation of adipose-derived stem cells improves functional recovery of skeletal muscle without direct participation in new myofiber formation
Stem Cell Research & Therapy, 2018Co-Authors: Agata Gorecka, Daniel Eberli, Souzan Salemi, Deana Haralampieva, Federica Moalli, Deborah Stroka, Daniel Candinas, Lukas BrüggerAbstract:Background Skeletal muscle has a remarkable Regenerative capacity. However, extensive damage that exceeds the self-Regenerative Ability of the muscle can lead to irreversible fibrosis, scarring, and significant loss of function. Adipose-derived stem cells (ADSC) are a highly abundant source of progenitor cells that have been previously reported to support the regeneration of various muscle tissues, including striated muscles. The aim of this study was to evaluate the effect of ADSC transplantation on functional skeletal muscle regeneration in an acute injury model. Methods Mouse ADSC were isolated from subcutaneous fat tissue and transplanted with a collagen hydrogel into the crushed tibialis anterior muscle of mice. Recovering muscles were analyzed for gene and protein expression by real-time quantitative polymerase chain reaction and immunohistochemistry. The muscle contractility was assessed by myography in an organ bath system. Results Intramuscular transplantation of ADSC into crushed tibialis anterior muscle leads to an improved muscle regeneration with ADSC residing in the damaged area. We did not observe ADSC differentiation into new muscle fibers or endothelial cells. However, the ADSC-injected muscles had improved contractility in comparison with the collagen-injected controls 28 days post-transplantation. Additionally, an increase in fiber cross-sectional size and in the number of mature fibers with centralized nuclei was observed. Conclusions ADSC transplantation into acute damaged skeletal muscle significantly improves functional muscle tissue regeneration without direct participation in muscle fiber formation. Cellular therapy with ADSC represents a novel approach to promote skeletal muscle regeneration.
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Autologous transplantation of adipose-derived stem cells improves functional recovery of skeletal muscle without direct participation in new myofiber formation.
Stem cell research & therapy, 2018Co-Authors: Agata Gorecka, Daniel Eberli, Souzan Salemi, Deana Haralampieva, Federica Moalli, Deborah Stroka, Daniel Candinas, Lukas BrüggerAbstract:Skeletal muscle has a remarkable Regenerative capacity. However, extensive damage that exceeds the self-Regenerative Ability of the muscle can lead to irreversible fibrosis, scarring, and significant loss of function. Adipose-derived stem cells (ADSC) are a highly abundant source of progenitor cells that have been previously reported to support the regeneration of various muscle tissues, including striated muscles. The aim of this study was to evaluate the effect of ADSC transplantation on functional skeletal muscle regeneration in an acute injury model. Mouse ADSC were isolated from subcutaneous fat tissue and transplanted with a collagen hydrogel into the crushed tibialis anterior muscle of mice. Recovering muscles were analyzed for gene and protein expression by real-time quantitative polymerase chain reaction and immunohistochemistry. The muscle contractility was assessed by myography in an organ bath system. Intramuscular transplantation of ADSC into crushed tibialis anterior muscle leads to an improved muscle regeneration with ADSC residing in the damaged area. We did not observe ADSC differentiation into new muscle fibers or endothelial cells. However, the ADSC-injected muscles had improved contractility in comparison with the collagen-injected controls 28 days post-transplantation. Additionally, an increase in fiber cross-sectional size and in the number of mature fibers with centralized nuclei was observed. ADSC transplantation into acute damaged skeletal muscle significantly improves functional muscle tissue regeneration without direct participation in muscle fiber formation. Cellular therapy with ADSC represents a novel approach to promote skeletal muscle regeneration.
James W. Fawcett - One of the best experts on this subject based on the ideXlab platform.
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Selective rab11 transport and the intrinsic Regenerative Ability of CNS axons
eLife, 2017Co-Authors: Hiroaki Koseki, Matteo Donegà, Brian Yh Lam, Veselina Petrova, Susan Van Erp, Giles S.h. Yeo, Jessica C. F. Kwok, Charles Ffrench-constant, Richard Eva, James W. FawcettAbstract:The nerves in the brain and spinal cord can be damaged by trauma, stroke and other conditions. Damage to these nerve fibres can destroy the connections they form with each other, which may lead to paralysis, loss of sensation and loss of body control. If we could stimulate the regeneration and reconnection of the damaged nerve fibres then neurological function could be restored. However, although embryonic nerve fibres can regenerate when they are transplanted into the adult central nervous system, this Regenerative Ability appears to be lost as the nerve fibres mature. To investigate when and why nerve fibres lose the Ability to regenerate, Koseki et al. first developed a tissue culture assay in which individual nerve fibres were cut with a laser and imaged for several hours to track their regeneration (or failure to regenerate). The results demonstrate that nerve fibres from the central nervous system progressively lose the Ability to grow and regenerate as they mature. To investigate why mature nerve fibres cannot regenerate, Koseki et al. measured whether nerve fibres can transport some of the molecules needed for growth and regeneration to sites of damage. This showed that the compartments in which some key growth molecules are transported become excluded from mature nerve fibres. These compartments are marked by a protein called rab11, and Koseki et al. found that forcing rab11 back into mature nerve fibres restored their Ability to regenerate. There is still a lot of work needed before these findings can lead to a new regeneration treatment for patients, but it is a crucial step forwards. Furthermore, the assay developed by Koseki et al. could be used to develop and test such treatments.
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differential Regenerative Ability of sensory and motor neurons
Neuroscience Letters, 2017Co-Authors: Menghon Cheah, James W. Fawcett, Barbara HaenziAbstract:After injury, the adult mammalian central nervous system (CNS) lacks long-distance axon regeneration. This review discusses the similarities and differences of sensory and motor neurons, seeking to understand how to achieve functional sensory and motor regeneration. As these two types of neurons respond differently to axotomy, growth environment and treatment, the future challenge will be on how to achieve full recovery in a way that allows regeneration of both types of fibres simultaneously.
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Overcoming inhibition in the damaged spinal cord.
Journal of neurotrauma, 2006Co-Authors: James W. FawcettAbstract:Inhibition by several inhibitory molecules on oligodendrocytes, and by chondroitin sulphate proteoglycans and semaphorins in the glial scar discourages regeneration of axons in the injured spinal cord. This inhibition is compounded by the poor Regenerative Ability of most central nervous system (CNS) axons. Treatments that block some of these inhibitory mechanisms promote regeneration in animal models of cord injury. Plasticity is also reduced by some of the inhibitory molecules, and some of the treatments that promote regeneration also promote plasticity. This is probably a more achievable therapeutic target than axon regeneration, and an effective treatment would be of assistance to the majority of patients with partial cord injuries.
Sunjay Kaushal - One of the best experts on this subject based on the ideXlab platform.
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abstract 18377 hypoplastic left heart syndrome derived cardiac stem cells show a strong Regenerative Ability
Circulation, 2013Co-Authors: Rachana Mishra, Sudhish Sharma, Ling Chen, Savitha Desmukh, Sunjay KaushalAbstract:Background: Human adult c-kit+ cardiac stem cells (CSCs) alleviates post-myocardial infarction left ventricle dysfunction in animal models and a Phase I clinical study. The Regenerative capacity of...
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abstract 243 end stage heart failure cardiac stem cells has strong Regenerative Ability compared to congenital heart cardiac stem cells
Circulation Research, 2013Co-Authors: Rachana Mishra, David Simpson, Sudhish Sharma, Savitha Desmukh, Sunjay KaushalAbstract:Cellular based therapy is an important component of cardiac Regenerative medicine. We have already identified and characterized a small population of undifferentiated cells present throughout the h...
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A Strong Regenerative Ability of Cardiac Stem Cells Derived From Neonatal Hearts
Circulation, 2012Co-Authors: David Simpson, Rachana Mishra, Sudhish Sharma, Saik Kia Goh, Savitha Deshmukh, Sunjay KaushalAbstract:Background—Human cardiac stem cells (CSCs) promote myocardial regeneration in adult ischemic myocardium. The Regenerative capacity of CSCs in very young patients with nonischemic congenital heart defects has not been explored. We hypothesized that isolated neonatal-derived CSCs may have a higher Regenerative Ability than adult-derived CSCs and might address the structural deficiencies of congenital heart disease. Methods and Results—Human specimens were obtained during routine cardiac surgical procedures from right atrial appendage tissue discarded from 2 age groups: neonates and adults patients. We developed a reproducible isolation method that generated cardiosphere-derived cells (CDCs), regardless of starting tissue weight or age. Neonatal-derived CDCs demonstrated increased number of cardiac progenitor cells expressing c-kit+, flk-1, and Islet-1 by flow cytometry and immunofluorescence. When transplanted into infarcted myocardium, neonatal-derived CDCs had a significantly higher Ability to preserve my...
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abstract 13138 a strong Regenerative Ability of cardiac progenitor cells in hypoplastic left heart syndrome patients a preclinical study
Circulation, 2011Co-Authors: Sunjay Kaushal, David Simpson, Rachana Mishra, Sudhish Sharma, Carl L Backer, Richard G Ohye, Elfriede PahlAbstract:Background: Human cardiac progenitor cells (hCPCs) may promote myocardial regeneration in adult ischemic myocardium. The Regenerative capabilities of hCPCs in young patients with non-ischemic conge...
