GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Myonucleus-Related Properties in Soleus Muscle Fibers of 〈i〉mdx〈/i〉 Mice
    S. Karger AG ; 2010
    In:  Cells Tissues Organs Vol. 191, No. 3 ( 2010), p. 248-259
    Details
    In: Cells Tissues Organs, S. Karger AG, Vol. 191, No. 3 ( 2010), p. 248-259
    Abstract: Distribution and total number of myonuclei in single soleus muscle fibers, sampled from tendon to tendon, were analyzed in 〈 i 〉 mdx 〈 /i 〉 and wild-type (WT) mice. Apoptotic myonuclei and the microscopic structure around the myonuclei were also analyzed. Three types of muscle fibers of 〈 i 〉 mdx 〈 /i 〉 mice with myonuclear distribution at either central, peripheral, or both central and peripheral regions were observed in the longitudinal analyses. All of the myonuclei were located at the peripheral region in WT mice. The total number of myonuclei counted in the whole length of fibers with peripheral myonuclei only was 17% less in 〈 i 〉 mdx 〈 /i 〉 than in WT mice (p 〈 0.05). But the total myonuclear numbers in 〈 i 〉 mdx 〈 /i 〉 mouse fibers with different distribution (peripheral vs. central) of myonuclei were identical, and the peripheral nucleus was noted where the central nucleus was missing. Myonuclei located between the center and peripheral regions were also seen in the cross-sectional analyses of muscle fibers. The cross-sectional area and length of fibers, sarcomere number, myonuclear size, myosin heavy chain expression, satellite cell number and neuromuscular junction were identical between each type of fiber. Apoptosis was not detected in any myonuclei located either in central or peripheral regions of muscle fibers. Thus, it was suggested that apoptosis-related loss of central myonuclei and regeneration-related new accretion at the peripheral region is not the cause of different distribution of myonuclei seen in muscle fibers in 〈 i 〉 mdx 〈 /i 〉 mice. However, it was speculated that cross-sectional migration of myonuclei from central to peripheral regions may be induced in response to regeneration, because the total myonuclear numbers in fibers with different distribution of myonuclei were identical, and the peripheral nucleus was noted where the central nucleus was missing. Further, myonuclei located between the center and peripheral regions were also seen. However, the question remains as to how or why nuclei might migrate to the periphery in a regenerating muscle fiber, since there was no microscopic evidence of any structural changes around the myonuclei that may be responsible for the movement of the nucleus.
    Type of Medium: Online Resource
    ISSN: 1422-6405 , 1422-6421
    URL: Article
    DOI: 10.1159/000240245
    Language: English
    Publisher: S. Karger AG
    Publication Date: 2010
    detail.hit.zdb_id: 1481840-1
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Cortical Actin Alteration at the Matrix-Side Cytoplasm in Lung Adenocarcinoma Cells and Its Significance in Invasion
    S. Karger AG ; 2017
    In:  Pathobiology Vol. 84, No. 4 ( 2017), p. 171-183
    Details
    In: Pathobiology, S. Karger AG, Vol. 84, No. 4 ( 2017), p. 171-183
    Abstract: 〈 b 〉 〈 i 〉 Objectives: 〈 /i 〉 〈 /b 〉 Cortical actin is a thin layer of filamentous (F-)actin that lies beneath the plasma membrane, and its role in pathophysiology remains unclear. We investigated the subcellular localization of cortical actin by the histopathological and experimental studies of lung adenocarcinomas. 〈 b 〉 〈 i 〉 Materials and Methods: 〈 /i 〉 〈 /b 〉 The subcellular localization of cortical actin was studied in surgically resected lung adenocarcinomas tissues and in 3-dimensionally cultured lung adenocarcinoma A549 cells. 〈 b 〉 〈 i 〉 Results: 〈 /i 〉 〈 /b 〉 In normal type II alveolar cells and the bronchiolar epithelium, cortical actin was localized to the apical-side cytoplasm. In invasive adenocarcinoma cells, cortical actin was frequently localized to the matrix side. The degree of cortical actin localized to the matrix side was associated with the loss of basement membrane and a poor prognosis. In A549 cell spheroids cultured in a type I collagen and basement membrane extract Matrigel™ mixed gel, cortical F-actin was localized to the matrix side with phosphorylated myosin light chain. Super-resolution and electron microscopy results suggest that compact wrinkling of the plasma membrane by myosin-mediated F-actin contraction is an explanation for cortical actin accumulation at the matrix side. The myosin II inhibitor blebbistatin suppressed the 3-dimensional collective migration of A549 cells induced by constitutively active Cdc42 and MT1-MMP. 〈 b 〉 〈 i 〉 Conclusion: 〈 /i 〉 〈 /b 〉 Cortical actin accumulation at the matrix-side cytoplasm of cancer cells occurs in invasive lung adenocarcinomas and it possibly participates in the migration of cancer cells through myosin-mediated contraction.
    Type of Medium: Online Resource
    ISSN: 1015-2008 , 1423-0291
    URL: Article
    DOI: 10.1159/000452838
    Language: English
    Publisher: S. Karger AG
    Publication Date: 2017
    detail.hit.zdb_id: 1483541-1
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    The Role of Neural and Mechanical Influences in Maintaining Normal Fast and Slow Muscle Properties
    S. Karger AG ; 2006
    In:  Cells Tissues Organs Vol. 182, No. 3-4 ( 2006), p. 129-142
    Details
    In: Cells Tissues Organs, S. Karger AG, Vol. 182, No. 3-4 ( 2006), p. 129-142
    Abstract: The relative importance of neural and mechanical influences in maintaining normal slow and fast muscle properties remains unclear. To address this issue, we studied the effects of 10 days of hindlimb unloading (HU) with or without tenotomy and/or denervation on the cross-sectional area (CSA), myosin heavy chain (MHC) expression (immunohistochemistry) and composition (gel electrophoresis), and myonuclear number in soleus and plantaris fibers in adult male Wistar rats. In general, the adaptations in fiber type and size were similar using either single fiber gel or immunohistochemical analyses. HU resulted in atrophy of type I and I+IIa/x MHC fibers in the soleus and in type I, I+IIa/x, IIa/x, IIa/x+IIb, and IIb MHC fibers in the plantaris. Addition of tenotomy and/or denervation in HU rats had minimal effects on fiber CSA in the soleus, but fiber CSA in the plantaris further decreased, particularly in fibers expressing only fast MHCs. HU resulted in a de novo appearance of type I+IIa/x+IIb and IIa/x+IIb MHC fibers in the soleus and of type I+IIa/x+IIb MHC fibers in the plantaris.Tenotomy and/or denervation in HU rats had no further effect on the fiber type composition of either muscle. Mean myonuclear number/mm of type I fibers was decreased in the soleus of HU rats, and increased in type I and I+IIa/x fibers in HU plus tenotomy (HU+Ten) rats. In the plantaris, mean myonuclear number/mm of type IIa/x, IIa/x+IIb, and IIb fibers was lower after HU with or without tenotomy and/or denervation. Mean cytoplasmic volume/myonucleus ratio of type I and I+IIa/x fibers in the soleus of the HU group tended to be smaller than in controls. The largest decrease was noted in the HU+Ten group. In the plantaris, this ratio was unaffected by HU alone, but was decreased by addition of tenotomy and/or denervation when all fiber types were combined. These data indicate that the major cause of fiber atrophy and adaptations in myonuclear domain size in the slow soleus of HU rats is the chronic reduction in force generation, whereas the elimination of neuromuscular contact via denervation results in additional fiber atrophy and adaptations in myonuclear domain size in the fast plantaris.
    Type of Medium: Online Resource
    ISSN: 1422-6405 , 1422-6421
    URL: Article
    DOI: 10.1159/000093963
    Language: English
    Publisher: S. Karger AG
    Publication Date: 2006
    detail.hit.zdb_id: 1481840-1
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...