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Striated Muscle Cells (striated + muscle_cell)

Distribution by Scientific Domains
Life Sciences83%

Selected Abstracts

Ultrastructural analysis of the smooth-to-striated transition zone in the developing mouse esophagus: Emphasis on apoptosis of smooth and origin and differentiation of striated muscle cells

DEVELOPMENTAL DYNAMICS, Issue 3 2005
Jürgen Wörl
Abstract The exact mechanism of smooth-to-striated muscle conversion in the mouse esophagus is controversial. Smooth-to-striated muscle cell transdifferentiation vs. distinct differentiation pathways for both muscle types were proposed. Main arguments for transdifferentiation were the failure to detect apoptotic smooth and the unknown origin of striated muscle cells during esophageal myogenesis. To reinvestigate this issue, we analyzed esophagi of 4-day-old mice by electron microscopy and a fine-grained sampling strategy considering that, in perinatal esophagus, the replacement of smooth by striated muscle progresses craniocaudally, while striated myogenesis advances caudocranially. We found numerous (1) apoptotic smooth muscle cells located mainly in a transition zone, where smooth intermingled with developing striated muscle cells, and (2) mesenchymal cells in the smooth muscle portion below the transition zone, which appeared to give rise to striated muscle fibers. Taken together, these results provide further evidence for distinct differentiation pathways of both muscle types during esophagus development. Developmental Dynamics 233:964,982, 2005. © 2005 Wiley-Liss, Inc. [source]

Bves expression during avian embryogenesis

DEVELOPMENTAL DYNAMICS, Issue 3 2004
Megan E. Osler
Abstract Bves (blood vessel/epicardial substance) is a transmembrane protein postulated to play a role in cell adhesion. While it is clear that Bves and gene products of the same family are expressed in adult striated muscle cells, the distribution of these proteins during development has not been critically examined. An understanding of the expression pattern of Bves is essential for a determination of protein function and its role in embryogenesis. In this study, we present an expression analysis of Bves during chick gastrulation and germ layer formation. Our data show that Bves is expressed in epithelia of all three germ layers early in development. Furthermore, Bves protein is observed in epithelial tissues during organogenesis, specifically the developing epidermis, the gut endoderm, and the epicardium of the heart. These data support the hypothesis that Bves may play a role in cell adhesion and movement of epithelia during early embryogenesis. Developmental Dynamics 229:658,667, 2004. © 2004 Wiley-Liss, Inc. [source]

Autologous bone-marrow-derived mesenchymal stem cell transplantation into injured rat urethral sphincter

INTERNATIONAL JOURNAL OF UROLOGY, Issue 4 2010
Yoshiaki Kinebuchi
Objectives: To evaluate the functional and histological recovery by autologous bone-marrow-derived mesenchymal stem cell (BMSC) transplantation into injured rat urethral sphincters. Methods: BMSC were harvested from female Sprague,Dawley retired breeder rats for later transplantation. The cells were cultured, and transfected with the green fluorescence protein gene. The urethral sphincters were injured by combined urethrolysis and cardiotoxin injection. One week after injury, the cultured BMSC were injected autologously into the periurethral tissues. Controls included sham-operated rats and injured rats injected with cell-free medium (CFM). Abdominal leak point pressures (LPP) were measured before and after surgery during the following 13 weeks. The urethras were then retrieved for histological evaluation. The presence of green-fluorescence-protein-labeled cells and the regeneration of skeletal muscles, smooth muscles, and peripheral nerves were evaluated by immunohistochemical staining. Results: LPP was significantly reduced in the injured rats. It increased gradually after transplantation, but there was no significant difference between the BMSC and CFM groups. In the BMSC group, transplanted cells survived and differentiated into striated muscle cells and peripheral nerve cells. The proportions of skeletal muscle cells and peripheral nerves in the urethra were significantly greater in the BMSC group compared to the CFM group. Conclusions: Despite a clear trend towards recovery of LPP in BMSC-transplanted urethras, no significant effect was detected. Further study is required for clinical applications for the treatment of stress urinary incontinence. [source]

Control of asymmetric cell divisions: will cnidarians provide an answer?

BIOESSAYS, Issue 9 2004
Thomas C.G. Bosch
Cells in the basal metazoan phylum Cnidaria are characterized by remarkable plasticity in their differentiation capacity. The mechanism controlling asymmetric cell divisions is not understood in cnidarians or in any other animal group. PIWI proteins recently have been shown to be involved in maintaining the self-renewal capacity of stem cells in organisms as diverse as ciliates, flies, worms and mammals. Seipel et al.1 find that, in the cnidarian Podocoryne carnea, the Piwi homolog Cniwi is transcriptionally upregulated when the polyp generates buds, which will develop into medusae. Since transdifferentiation of striated muscle cells to smooth muscle cells also activated Cniwi expression, Cniwi appears to play a crucial role in differentiation events. The discovery should facilitate elucidation of the poorly understood factors that control asymmetric cell divisions at the beginning of animal evolution. BioEssays 26:929,931, 2004. © 2004 Wiley Periodicals, Inc. [source]