Search results for "basement membrane"
showing 10 items of 80 documents
The mechanism of epithelial shedding after ischemic damage to the small intestinal mucosa
1979
The intestinal mucosa of the rat was examined by light and electron microscopy 15, 30, 60 and 120 min after complete ligation of the vessel arcades of the proximal jejunum. The characteristic sign of ischemic damage to the small intestinal mucosa and the reason for epithelial shedding is the appearance of membrane enclosed cytoplasmic blebs which arise at the cell base of the enterocytes and detach the epithelium from the basement membrane. This process begins at the tip of the villi before the enterocytes display signs of irreversible damage and progress to the base of the villi with continuation of the ischemia.
Perlecan controls neurogenesis in the developing telencephalon.
2006
This article is available from: http://www.biomedcentral.com/1471-213X/7/29
Perlecan-Induced Suppression of Smooth Muscle Cell Proliferation Is Mediated Through Increased Activity of the Tumor Suppressor PTEN
2004
We were interested in the elucidation of the interaction between the heparan sulfate proteoglycan, perlecan, and PTEN in the regulation of vascular smooth muscle cell (SMC) growth. We verified serum-stimulated DNA synthesis, and Akt and FAK phosphorylation were significantly reduced in SMCs overexpressing wild-type PTEN. Our previous studies showed perlecan is a potent inhibitor of serum-stimulated SMC growth. We report in the present study, compared with SMCs plated on fibronectin, serum-stimulated SMCs plated on perlecan exhibited increased PTEN activity, decreased FAK and Akt activities, and high levels of p27, consistent with SMC growth arrest. Adenoviral-mediated overexpression of cons…
Effects of aging and life-long physical training on collagen in slow and fast skeletal muscle in rats. A morphometric and immuno-histochemical study.
1987
Intramuscular collagen in a slow (m. soleus) and a fast (m. rectus femoris) skeletal muscle was studied by biochemical, morphometric, and immunohistochemical methods. Wistar white rats of 1, 4, 10, and 24 months were used as experimental animals. Our aim was to evaluate the effects of life-long physical training (treadmill running, 5 days a week for 1, 3, 9, and 23 months depending on the age attained). The biochemical concentration of collagen was higher in m. soleus than in m. rectus femoris and it increased in youth and in old age in m. soleus. The trained rats had higher concentrations of collagen than the untrained rats at 10 and 24 months. The morphometrically measured area-fractions …
Dot-immunobinding assay with the globular domain of collagen type IV for antiglomerular basement membrane antibodies
1988
A dot-immunobinding assay for the detection of antiglomerular basement membrane antibodies has been developed. The globular domain NC1 of basement membrane collagen type IV was used as antigen. The assay proved to be specific, sensitive, and reproducible. Circulating antibodies in each of 12 sera from patients with florid Goodpasture's syndrome could be demonstrated, whereas sera from patients with Goodpasture's syndrome in clinical remission and various control sera showed no reactivity. The advantages of the dot-blot assay are: the usage of the purified Goodpasature target antigen NCI reduces unspecific binding of IgG; only minimal amounts of antigen are required to give a positive signal…
Redistribution of aquaporin-4 in human glioblastoma correlates with loss of agrin immunoreactivity from brain capillary basal laminae
2003
Vasogenic edema is one of the most serious clinical problems in brain tumors and tightly connected to water shifts between the different fluid compartments in the brain. Aquaporin water channels have been recognized to have an important impact on the development of edematous swelling in the brain. Astrocytes, which are believed to induce or at least maintain the blood-brain barrier in the brain capillary endothelial cells, express the aquaporin isoform AQP4. Normally, AQP4 is highly concentrated in the glial membrane where astrocytes contact mesenchymal space, such as perivascular or brain superficial regions. Parenchymal membranes do not show any immunocytochemical AQP4-specific signal. We…
Effect of Prolonged Physical Training on the Development of Connective Tissues in Growing Mice
1975
A rapid progress has taken place in the field of connective tissue chemistry during recent years. The structure and metabolism of collagen, elastin, glycosaminoglycans and pro-. teoglycans of different connective tissues have been extensively investigated. One of the main observations has been that large differences exist between various connective tissues [12]. For example, four different forms of collagen have been identified. The collagens in bone, cartilage, skin and basement membrane have either different amino acid composition in the a-chains or contain one or two similar a-chains in the triple helix. The scope of the connective tissue research has been extended also to skeletal muscl…
The fine structure of de-and reinnervated muscle spindles
1974
Reinnervated muscle spindles in lower lumbrical muscles of rats studied 17 days to 24 months after crushing the sciatic nerve showed a series of alterations which have not been analysed, thus far, by electron microscopy. There was a striking increase of the number of intrafusal muscle fibers seen in approximately 20% of reinnervated spindles. These spindles showed 5–11 intrafusal muscle fibers whereas normal spindles usually contained 3–4 fibers only.
CONVENTIONAL INTERNAL LIMITING MEMBRANE PEELING VERSUS INVERTED FLAP FOR SMALL-TO-MEDIUM IDIOPATHIC MACULAR HOLE
2022
Purpose: To compare conventional internal limiting membrane (ILM) peeling versus inverted flap technique in small-to-medium idiopathic macular hole. Methods: Eyes with ≤400 μ m idiopathic macular holes were randomized into the conventional ILM peeling group (25 eyes) and inverted flap group (25 eyes). A 12-month follow-up was considered. Macular sensitivity (MS) change detected with MP-1 microperimetry was the primary outcome. Secondary outcomes included best-corrected visual acuity change, closure rate, anatomical findings on optical coherence tomography such as U-shape foveal contour, restoration of external limiting membrane, and ellipsoid zone. Results: In both groups, MS improved throu…
Perlecan is critical for heart stability
2008
Aims Perlecan is a heparansulfate proteoglycan found in basement membranes, cartilage, and several mesenchymal tissues that form during development, tumour growth, and tissue repair. Loss-of-function mutations in the perlecan gene in mice are associated with embryonic lethality caused primarily by cardiac abnormalities probably due to hemopericards. The aim of the present study was to investigate the mechanism underlying the early embryonic lethality and the pathophysiological relevance of perlecan for heart function. Methods and results Perlecan-deficient murine embryonic stem cells were used to investigate the myofibrillar network and the electrophysiological properties of single cardiomy…