摘要:

The expression and induction of heat shock proteins (HSPs) were examined in cultured SV-40-transformed human retinal pigment epithelial (RPE)-derived cells following exposure to chemical oxidants. Concentrations of hydrogen peroxide and the organic oxidants tert-butyl hydroperoxide, cumene hydroperoxide and linoleic acid hydroperoxide were used under conditions where cell viability was between 75% and 90% as determined by the trypan blue exclusion tests. The types of HSPs that are either induced and/or elevated from constitutive levels in cultured transformed cells were separated both by SDS-PAGE and by two-dimensional gel electrophoresis. Subsequent immunoblotting was performed with both a monoclonal antibody (MAb C92) specific for only the stress-inducible form of HSP 70, namely HSP 72, and with a monoclonal antibody (MAb N27) specific for both the stress-inducible HSP 72 and its constitutive form, HSP 73. As positive controls for comparison, other types of stressing agents were used that included heat shock at 41°C for various times and exposure to the proline analogue, azetidine-2-carboxylic acid (AzC). Protein immunoblotting analysis demonstrate that: (a) Stress-inducible HSP 72 is present at low levels in non-stressed cultured transformed RPE-derived cells and in fresh bovine retina and RPE, but is not detectable in non-stressed cultured lung fibroblasts until induction with heat shock; and (b) Stress-inducible HSP 72 is elevated from constitutive levels in RPE-derived cultured cells after exposure to various oxidants. After cellular exposure to both organic oxidants and to AzC in the presence of L-[35-S]-methionine, two-dimensional gel electrophoresis confirmed the elevation of newly synthesized HSP 72. Thus, these results indicate that cultured human SV-40-tranformed RPE-derived cells are capable of elevated HSP 72 biosynthesis under conditions of oxidative stress produced by organic oxidants.

ISSN:0271-3683    

DOI:10.3109/02713689209001792

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

摘要:

We investigated the glycoconjugates in frozen sections of keratoconus corneas, using a panel of 12 biotin- or f1uoresce in isothiocyanate-labeled lectins. No differences between the lectin binding sites of the epithelium, endothelium and Descemet's membrane of normal and keratoconus corneas could be observed. However, in contrast to normal corneas, intense staining with peanut agglutinin (PNA) could be detected at breaks in Bowman's layer, in scar tissue and in the adjacent stroma. Furthermore, in the majority of cases binding sites for Phaseolus vulgaris erythroagglutinin (PHA-E) and increased staining with Ricinus communis agglutinin I (RCA-I) and Lens culinaris agglutinin (LCA) could also be detected in ruptures in Bowman's layer and in scar tissue.These data suggest that the scarred regions of the anterior stroma in keratoconus corneas may contain oligosaccharides with terminal D-galactose (β1-3)-D-N-acetylgalactosamine disaccharides (recognized by PNA), increased amounts of glycoconjugates with terminalβ-galactose residues (recognized by RCA-I), increased amounts of glycoconjugates with glucose/mannose residues (recognized by LCA), and finally, biantennary complex-type glycopeptides containing two outer galactose residues and a residue of N-acetylglucosamine (recognized by PHA-E). Since corneal scars due to causes other than keratoconus revealed lectin binding sites (particularly for PNA and to a lesser extent also for PHA-E, LCA and RCA-I) similar to those seen in scar tissue of keratoconus corneas, we conclude that it is mainly scar formation that may be responsible for the altered lectin binding sites in keratoconus.

ISSN:0271-3683    

DOI:10.3109/02713689209001793

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

ISSN:0271-3683    

DOI:10.3109/02713689209001794

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

ISSN:0271-3683    

DOI:10.3109/02713689209001795

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

摘要:

Histopathology revealed mostly poorly differentiated tumors with necrosis and lack of Flexner-Wintersteiner rosettes. Immunocytochemical staining showed focal IRBP expression in one of the tumors and S-antigen in two cases. Immunoreactivity with rhodopsin was negative. N-CAM, a neural adhesive protein which appears to be involved in the regulation of adhesive interaction during neuronal differentiation, was positive except in two cases. All tumors showed immunoreactivity with NSE, whereas GFAP staining was limited to the perivascular glial tissue confirming the essential neuronal nature of retinoblastoma cells. Tc was detected in all tumors and TRαin one case. Messenger RNA for IRBP was detected in tumors in which IRBP immunoreactivity could not be detected.

ISSN:0271-3683    

DOI:10.3109/02713689209001796

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

ISSN:0271-3683    

DOI:10.3109/02713689209001797

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

摘要:

In this study we have shown that PCR based tissue typing is more sensitive and gives more detailed typing results than serology and would be suitable to type cadaveric donor material on a routine basis.

ISSN:0271-3683    

DOI:10.3109/02713689209001798

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

ISSN:0271-3683    

DOI:10.3109/02713689209001799

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

ISSN:0271-3683    

DOI:10.3109/02713689209001800

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor

ISSN:0271-3683    

DOI:10.3109/02713689209001801

出版商:Taylor&Francis    

年代:1992

数据来源: Taylor