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H Sakai

Publications and source records attributed to H Sakai.

At least 1,099 records · Page 61Linked to original sources

Pathological characteristics of metastatic carcinoma in the human mandible.

Based on the large celloidin-embedded section method, human mandibles from 62 autopsied carcinoma cases were examined histologically to determine the pathological characteristics of any mandibular metastases. Metastasis was confirmed histologically in 10 (16%) of the 62 cases and was comparatively frequent with gastric and pulmonary carcinomas. The hemopoietic areas in the mandibular marrow seemed to favor the early deposition of tumor cells. These micrometastatic foci seemed to increase in size, spreading to all parts, including the periodontal tissue or anterior part of the mandibular body. Increased hemopoietic activity following lodgement, seemed to play an important role for further metastases. Roentgenographic examination did not seem to be the best method of detecting metastasis.

Adenocarcinoma↗

Modified open renal biopsy: results in 934 patients.

Nine hundred and thirty-four cases of open renal biopsy using the 'Kawamura-modified forceps' have been performed over the past 9 years under general anesthesia. Sufficient amounts of renal tissue for routine histology, immunofluorescence staining and electron microscopy were obtained in all 934 cases. There were no serious major complications attributable to the procedure. It is concluded that this procedure can be performed easier and faster than the previous technique of percutaneous renal biopsy, although patients undergoing open renal biopsy with the Kawamura-modified forceps have to be transferred to the operating room for this procedure.

Adolescent↗

A case of IgA nephropathy associated with adeno- and herpes simplex viruses.

We report here an adult case of IgA nephropathy associated with episodes of recurrent tonsillitis. Various kinds of viral antigens were examined in the renal and tonsillar tissues by immunofluorescence. Granular depositions of adeno- and herpes simplex viral antigens were detected in the glomerular mesangial areas and in the tonsillar epithelial cells by immunofluorescence. IgA and IgA1 deposits were also observed in the glomerular mesangial areas. It was suggested that IgA nephropathy might be caused by multiple antigenic substances, including adeno- and/or herpes simplex viruses, located in the tonsillar regions.

Adenoviruses, Human↗

Identification of the 190 kD microtubule-associated protein in cultured fibroblasts and its association with interphase and mitotic microtubules.

We previously investigated the biochemical characteristics of microtubule-associated proteins (MAPs) of the adrenal medulla and adrenal cortex and found that they contain a new kind of MAP with a molecular weight of 190,000 (190 kD MAP) as a major species (Kotani, S., H. Murofushi, S. Maekawa, C. Sato, and H. Sakai. Eur. J. Biochem. 156, 23-29, 1986). We now have used an affinity purified anti-(190 kD MAP) antibody and show by indirect immunofluorescent microscopy the association of this MAP with microtubules in situ in TIG-3 cells (human embryonic lung fibroblasts). The 190 kD MAP was present along the interphase and mitotic microtubules, and there was no marked difference between the staining pattern with anti-tubulin and that with anti-(190 kD MAP) antibodies, evidence that the localization of 190 kD MAP is not restricted to the subset of microtubules. We also isolated MAPs from TIG-3 cells and identified their 190 kD MAP as a major heat-stable component. Several other unidentified polypeptides were recovered in the MAP fraction specifically.

Fibroblasts↗

Redistribution of fluorescently labeled tubulin in the mitotic apparatus of sand dollar eggs and the effects of taxol.

Fluorescently labeled tubulin was quickly incorporated into the mitotic apparatus when injected into a live sand dollar egg. After a rectangular area (1.6 X 16 microns) of the mitotic spindle was photobleached at metaphase or anaphase by the irradiation of a laser microbeam, redistribution of fluorescence was almost complete within 30 sec. The photobleached area did not change in shape during the redistribution. During the period of redistribution, the bleached area moved slightly toward the near pole at metaphase and anaphase (means: 1.6 and 1.8 micron/min, respectively). These results indicate that redistribution was not due to the exchange of tubulin subunits only at the ends of microtubules but to their rapid exchange at sites along the microtubules in the bleached region. Furthermore, treadmilling of tubulin molecules along with the spindle microtubules possibly occurred at the rate of 1.6 micron/min at metaphase. Birefringence of the mitotic apparatus increased with a large increase in both the number and length of astral rays shortly after taxol was injected. However, the microtubules did not all seem to elongate at the same rate but appeared to become equalized in length. Chromosome movement stopped within 60 sec after the injection. Centrospheres became large and the labeled tubulin already incorporated into the centrospheres was excluded from the enlarged centrospheres. Shortly after the labeled tubulin was injected following the injection of taxol, it accumulated in the peripheral region of the centrospheres, suggesting that microtubules first assembled at this region. Fluorescently labeled tubulin in the mitotic apparatus in the egg after injection of taxol was redistributed much more slowly after photobleaching than in uninjected eggs.

Alkaloids↗

Distribution among tissues and intracellular localization of cofilin, a 21kDa actin-binding protein.

Cofilin, a 21kDa actin-binding protein, binds to F-actin in a 1:1 molar ratio of cofilin to actin molecule (Nishida, E., S. Maekawa, and H. Sakai, Biochemistry, 23, 5307-5313, 1984) and is capable of controlling actin polymerization and depolymerization in vitro in a pH-sensitive manner (Yonezawa, N., E. Nishida, and H. Sakai, J. Biol. Chem., 260, 14410-14412, 1985). In this study, immunoblot analysis using monospecific antibodies against cofilin showed that cofilin is ubiquitously distributed in a variety of bovine and rat organs and tissues. Cofilin is also present in various cultured cell lines. Indirect immunofluorescence staining of mouse fibroblastic cells and human epidermoid carcinoma cells indicated that cofilin is distributed nearly uniformly in the cytoplasm and is concentrated in ruffling membranes where F-actin is also concentrated as revealed by staining with rhodamine-phalloin. Stress fiber structures were not strongly stained with the anti-cofilin antibody, although stress fiber staining was sometimes observed near the cell periphery in mouse 3T3 cells. These results suggest that the bulk of cofilin may not be associated with F-actin bundles in vivo.

Actin Depolymerizing Factors↗

Clinical effect of danazol in patients with IgA nephropathy.

A multi-center study on the clinical effect of danazol in patients with IgA nephropathy is described. Two different doses of oral administration, including 200 mg or 300 mg per day, were employed in the present study. Urinalysis and measurements of complement components, i.e. C3 and C4, were performed before, and in the eighth and 20th week after the administration of danazol. It was demonstrated that 200 or 300 mg of danazol administration was effective in reducing the amount of proteinuria and in increasing the levels of serum complement components in the patients. It is concluded that the administration of danazol may be useful for treatment of patients with IgA nephropathy.

Administration, Oral↗

Detection of IgA-class circulating immune complexes (CIC) in sera from patients with IgA nephropathy using a solid-phase anti-C3 Facb enzyme immunoassay (EIA).

The detection of circulating immune complexes (CIC) in sera from patients with IgA nephropathy is described. A solid-phase anti-C3 Facb enzyme immunoassay (EIA) was employed for detection of IgA-, IgG- and IgM-CIC in sera. The C1q-binding enzyme assay was also used for the detection of CIC in sera from these patients and healthy adults. Twenty-two patients with IgA nephropathy, 14 patients with other glomerular diseases and 19 healthy adults were examined by anti-C3 Facb EIA. The levels of IgA-CIC in sera from patients with IgA nephropathy were significantly higher than those in sera from patients with other glomerular diseases and healthy adults. CIC measured by the C1q-binding enzyme assay was detected in some patients with IgA nephropathy. The levels of serum IgA in patients with IgA nephropathy were significantly higher than those in patients with other glomerular diseases and healthy adults. However, there was no significant correlation between the levels of IgA-CIC in sera and those of serum IgA in patients with IgA nephropathy. There was also no significant correlation between the levels of IgA-CIC in sera and the degree of histopathological injuries in the patients. It is concluded that the solid-phase anti-C3 Facb EIA is useful for the detection of IgA-CIC in sera from patients with IgA nephropathy.

Adult↗