ISSN:1065-6995    

DOI:10.1006/cbir.1995.1025

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractThe present paper deals with the comparative EM study of the detachment of mouse urinary bladder epithelial cells under various physiological conditions, namely, during gestation and in adult mice following induction by endotoxin or by exposure to moderate stress. It has been shown that desquamation during gestation involves two distinct modes, shedding of single cells and formation of apoptotic bodies. Moderate stress in adult female mice induced by constant illumination for 72 or 96 hours, results in desquamation of superficial and intermediate cells. Application of LPS is followed by desquamation of single cells and whole sheets of cells.Cell detachment involves interruption of tight junctions between neighbouring cells and formation of numerous cup shaped vesicles, multivesicular bodies and vacuoles at the base of desquamating cells. LPS induces desquamation entails delivery of lysosomal enzymes extracellulary into the intercellular space. In the areas of sloughing the bladder epithelium lack permeability barrier. Desquamated cells in the bladder lumen are mostly alive. These results clearly demonstrate the existence of specific adhesion mechanisms of detachment and desquamation of uroepithelial cells.

ISSN:1065-6995    

DOI:10.1006/cbir.1995.1026

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractRetinoic acid (RA), known for its important role in cellular differentiation, may cause a modification of glycolipid distribution characterized by a shift from globoserie towards latto‐ and ganglio‐series. In the present paper, we have investigated the modifications of the lipidic pattern after exogenous RA treatment of Xenopus embryos. We have noticed a decrease in neutral glycolipids with a parallel increase in gangliosides; the content of sulfatides does not seem to be modified. Beside the shift toward ganglio‐serie, we have also observed a redistribution inside this class of lipids. In particular, following RA treatment, the relative distribution of GD1b and GT1b increases while that of GM3 decr

ISSN:1065-6995    

DOI:10.1006/cbir.1995.1027

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractThe programmed cell death inducing effect of the EGF receptor tyrosine kinase inhibitor α‐cyano‐3,4‐dihydroxycinnamthioamide (AG213) was investigated in vitro on HT‐29 human colon tumor. AG213 at concentrations between 45 to 450 μM blocks the proliferation of HT‐29 cells. Morphological findings suggest that the selective tyrosine kinase inhibitor AG213 induces Clarke III type (non‐lysosomal vesiculate cytoplasmic) programmed cell death; unlike ATP analog non‐selective tyrosine kinase inhibitors like Genistein which were found to induce apoptosis. Cycloheximide and Actinomycin‐D reduced the effect of AG213 pointing to the fact that protein and RNA synthesis are also needed for this form of cell death. Acid phosphatase activity was found in the Golgi and in the newly formed intracytoplasmic vacuoles 3 hours after AG213 treatment which disappeared by 6 hours. The induction of Clarke III cell death by tyrosine kinase inhibitors may open a new modality to selective killi

ISSN:1065-6995    

DOI:10.1006/cbir.1995.1028

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractThis study tested several aspects of a model proposed by Williamson (1990, 1991) in which stresses in plant cell walls, detected by stress‐receptive portions of inelastic cellulose microfibrils, orient microtubules via interactions with cell wall‐linked transmembrane proteins. Young expanding cells of pea root tips have highly ordered transverse arrays of microtubules oriented perpendicular to the direction of cell expansion. The recovery of these ordered MT arrays after depolymerisation with oryzalin was assessed. It was shown that treating roots with disruptors of microfibril synthesis (2,6‐dichlorobenzonitrile and calcofluor white) or the disruption of Arg‐Gly‐Asp (RGD)‐mediated wall‐membrane links did not affect the orientation of recovering microtubule arrays. Furthermore, cell wall stresses themselves appeared unnecessary for regeneration of transverse arrays. The relevance of these findings to Williamson's hypothesis

ISSN:1065-6995    

DOI:10.1006/cbir.1995.1029

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractUltrastructural and light microscopic cytochemical methods were used to study the distribution and changes in distribution of alkaline phospatase in the apical plasma membrane of rat uterine epithelial cells during different stages of early pregnancy up to the time of attachment of the blastocyst. Reaction product generated by alkaline phosphatase (AP) was located along the apical plasma membrane at each stage investigated. However, a very different organization of reaction product was observed depending on the time during early pregnancy with a continuous pattern appearing all along the microvilli on day 1. This pattern was subsequently converted into a clumped and highly ‘patchy’ appearance around the time of blastocyst attachment by day 6 of pregnancy. This change in pattern and distribution was only seen on the luminal epithelial cells with glandular epithelial cells and blood vessels displaying an unchanging distribut

ISSN:1065-6995    

DOI:10.1006/cbir.1995.1030

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:1065-6995    

DOI:10.1006/cbir.1995.1031

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractSeveral synthetic decapeptides containing an HAV tripeptide motif were tested for their ability to modulate the enzymatic activity of rat extracellular SOD, an enzyme which also contains an HAV motif. Out of nine decapeptides that were tested, only a FGF‐receptor derived peptide was active as a negative modulator of enzyme activity. These results strenghten the thesis that HAV motifs are not only involved in homophilic interactions and suggest that soluble FGF‐receptor molecules might moderate the activity of extracellular

ISSN:1065-6995    

DOI:10.1006/cbir.1995.1032

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:1065-6995    

DOI:10.1006/cbir.1995.1033

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:1065-6995    

DOI:10.1006/cbir.1995.1034

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY