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Y Masugi

Publications and source records attributed to Y Masugi.

53 records · Page 3Linked to original sources

The significance of in vitro activation of guinea pig complement in glomeruli of human renal biopsy materials from varied subtypes of glomerulonephritis.

To measure the potential ability of complement activation by glomerular-bound immune complex or C3 convertase, the in vitro fixation of guinea pig complement (GPC) components to glomeruli was examined by immunofluorescence on the frozen sections of human renal biopsy materials, from the varied subtypes of glomerulonephritis (GN). Study for the pathway of complement activation in each subtype was also done. The extent of GPC activation fairly well paralleled with those of the autologous immunoreactants depositions and further with the morphological alterations of glomeruli in the cases of proliferative GN, advanced membranoproliferative GN (MPGN), lupus nephritis, purpura nephritis of non-IgA nephritis type and advanced focal segmental glomerular sclerosis. The ability of GPC activation was present but generally weak in the cases of post-streptococcal acute GN (post-str. AGN) and subsiding MPGN. The rate of positivity was further reduced in the cases of membranous nephropathy (MN), IgA nephritis and related purpura nephritis. The dominant alternative pathway of GPC activation was found in MPGN, post-str. AGN, IgA nephritis, and related purpura nephritis, the only classical pathway was noted in MN.

Adolescent↗

Immunopathologic studies of renal glomerular change in liver cirrhosis with special reference to its pathogenesis.

The kidneys from 62 proven liver cirrhosis cases were examined by immunofluorescence (IF), and 94% of the cases were positive for some immune reactants deposition. Combined deposition of immunoglobulin(s), both or each one of C1q and C4, and further with C3 were observed in about 70% of all IF positive cases. The morphological alterations of the glomeruli correlated with the intensities of regional immune reactants depositions. Guinea pig C3 was frequently activated in vitro on the glomeruli of these cases. Immune reactants depositions in the glomeruli appeared to form immune complex locally. Smooth muscle and liver cell antigens in the immune complex at the glomeruli were examined by indirect method of IF using monospecific antibodies and positive cases concerning each antigen were found in about 1/3 of the kidneys from 21 liver cirrhosis cases. These facts suggest that the high rate of the occurrence of immune complex deposition type glomerulo-nephritis may be due to the glomerular deposition of some autoantigen-antibody complexes including smooth muscle and liver cell antigens.

Adolescent↗

Membranous glomerulonephritis associated with active liver cirrhosis both involved by HBs antigen.

This is a case report of a 35-year-old female who showed a relatively short clinical course of severe liver cirrhosis and proteinuria. On light microscopical studies of autopsy material, besides active postnecrotic type liver cirrhosis, typical membranous glomerulonephritis was found. Immunofluorescent study disclosed not only clustered HBsAg (hepatitis type B surface antigen) in occasional hepatic cells but also beaded granular type deposition of HBsAg, IgG, IgM, IgA and complement C3 along renal glomerular basement membrane (GBM). Electron microscopical study disclosed multiple particulated material in occasional inclusion bodies of hepatic cells and in subepithelial and subendothelial dense deposits along the GBM. Enzymatic immunoelectron microscopical study confirmed these particles especially along the GBM being HBsAg themselves. It was concluded that HBsAg-Ab (antibody) complex was the pathogenetic factor responsible for the glomerular change of this particular case. Although HBsAg and Ab were examined to be negative in serum throughout the patient's clinical course, the possibility of the presence of circulating HBsAg-Ab complex in serum was discussed.

Adult↗

Renal lesions in a strain of spontaneously diabetic WBN/Kob rats.

In WBN/Kob strain rats, only males spontaneously develop hyperglycemia, glycosuria, hypoinsulinemia and glucose intolerance from about nine months of age. The kidneys of male rats of this strain were histopathologically studied to evaluate the changes which appeared as complications of diabetes mellitus. Thickening of the basement membrane, increase of the mesangial matrix and fibrin-cap lesions were noted in the glomeruli. Armanni-Ebstein degeneration was occasionally found in the tubules. Linear deposition of plasma components such as IgG and albumin in the basement membrane of the glomeruli, tubules and Bowman's capsule characterized the immunohistological pattern. These findings are similar to the findings in diabetic nephropathy in humans. Since the onset of diabetes mellitus in the strain is slow and symptoms are generally mild, insulin administration is usually not necessary for survival. This strain, therefore, appears to be an important animal model for the study of complications of diabetes in humans.

Animals↗