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Biomedical subjects

Y Kondo

Publications and source records attributed to Y Kondo.

At least 901 records · Page 50Linked to original sources
PubMed1983

Biliary cystadenocarcinoma diagnosed by liver biopsy performed under ultrasonographic guidance.

A case of a 60-yr-old man with biliary cystadenocarcinoma is reported. By needle biopsy of a cystic lesion performed under ultrasonographic guidance, overt malignant tissue could be obtained successfully. Histologic examination on autopsy material revealed that the tumor arose from preexisting benign liver cysts. The tumor showed a feature of well-differentiated, mucin-producing papillary adenocarcinoma in the primary site while, in the metastatic foci, it produced solid cell clusters with a tendency toward the differentiation into squamous cells.

Biopsy↗
PubMed1983

Renal vascular lesions in severe hypertension. Transitional changes from benign to malignant nephrosclerosis.

Renal vascular changes in severe hypertension were studied. Twenty-five cases selected from 4,629 autopsies were classified into 2 groups according to the cause of death: group 1 (9 cases died of renal failure) and group 2 (16 cases of extra-renal death). Group 1 had been clinically diagnosed as malignant hypertension and had the hallmarks of malignant nephrosclerosis characterized by arteriolar fibrinoid necrosis and edematous intimal thickening. Group 2 had been clinically diagnosed as benign hypertension and basically exhibited the changes of benign nephrosclerosis. However, about half of the cases of group 2 had arteriolar fibrinoid necrosis, though the lesion was usually less extensive than in group 1. Immunofluorescence revealed similar deposits of immunoglobulins and fibrinogen in the site of fibrinoid necrosis observed in both groups. As for the changes of interlobular arteries, a quantitative analysis disclosed a distinctive difference between groups 1 and 2 with respect to the narrowing ratio of arterial lumina, though edematous intimal thickening was recognized on relatively rare occasions in the distal interlobular arteries in a few cases of group 2. From the results, the problem of transition from the benign to malignant nephrosclerosis was discussed.

Adult↗
PubMed1982

Endocardial lesions in acute serum sickness in the rabbit. A scanning electron microscopic study.

Endocardial lesions in acute serum sickness in rabbits were studied with the aid of scanning electron microscopy (SEM). Prominent inflammation developed most often in the ventricular (pocket) side of the mitral valve and was confined to a hollowed area formed between valvular ridges. The early lesion consisted of swelling of endothelial cells with monocytic attachments. Subsequently, frequent endothelial perforations occurred, through which a number of monocytes emigrated into the subendothelial space. Focal or diffuse endothelial desquamation then followed. SEM revealed that the denuded basement membrane also had many perforations enabling monocytic emigration into the deeper valve layer. The accumulated monocytes and proliferating mesenchymal cells produced a granulomatous focus in the valvular tissue in which some monocytes were observed to convert to Anitschkow cells. Infiltration by polymorphs was minimal. Deposition of fibrin occurred in the more severe valvulitic lesions, but no verrucous vegetation formation was observed. The inflammatory process regressed rapidly, leaving focal areas of fibrosis. A possible pathogenesis is discussed in connection with the pathophysiologic conditions of the mitral valve pocket.

Animals↗
PubMed1982

Stimulation of tubulin-dependent ATPase activity in microtubule proteins from porcine brain by vinblas tine.

Vinblastine, a plant alkaloid which inhibits tubulin polymerization, stimulated an ATPase activity in microtubules. When microtubule proteins were separated into microtubule-associated proteins (MAPs) and tubulin by phosphocellulose column chromatography, vinblastine did not stimulate an ATPase activity recovered in the MAPs fraction unless tubulin was present. Therefore, vinblastine is considered to act through its binding to the tubulin molecule on MAPs ATPase. Divalent cations that activate tubulin-dependent MAPs ATPase activity were also required for the stimulation by vinblastine. In the presence of Ca2+ and vinblastine the ATPase activity was most active and the extent of stimulation reached about 200% of the original level in the absence of vinblastine. Half-maximal stimulation was attained when the molar ratio of vinblastine to tubulin was 0.5. The concentration of tubulin for half-maximal stimulation was increased in the presence of vinblastine, while divalent cation requirements were decreased. Several factors such as KCl (100 mM), alkaline pH (pH 7.5), and low temperature (10 degrees C) were not responsible for the disappearance of the stimulation. Vincristine stimulated tubulin-dependent MAPs ATPases activity as vinblastine did, whereas the activity was scarcely affected by colchicine, podophyllotoxin, strychnine, and chlorpromazine. Actin had no effect on MAPs ATPase activity in the absence and presence of vinblastine when it was used in place of tubulin.

Actins↗
PubMed1982

Immunohistocytochemical and immunofluorescent localization of catecholamine-synthesizing enzymes in the carotid body of the bat and dog.

By the immunoenzymatic PAP (peroxidase antiperoxidase) technique and immunofluorescent methods, the localization of a catecholamine-synthesizing enzyme, tyrosine hydroxylase (TH), in dopaminergic chief cells was elucidated in the dog and bat carotid bodies. Two types of cells were identified by PAP electron microscopy; TH-positive and TH-negative cells. The TH-positive reaction was observed both in the granules (about 170 and 300 nm in diameter) and in the ground substance, but not in the nucleus. Dopamine-beta-hydroxylase (DBH) reaction was negative in both cells. These findings may strongly suggest the presence of tyrosine hydroxylase not only in the cytoplasmic matrix but also in the granules in the dopaminergic cells of the carotid body.

Animals↗
PubMed1982

Experimental glomerulonephritis.

Our current understanding of glomerulonephritis has been established on the basis of experimental investigations. As shown in this short review, our knowledge is quite extensive, but still not enough to account for, in detail, the pathogenesis of diverse inflammatory processes occurring in the renal glomerulus. In this context, further correlated morphologic and immunopathologic studies need to be carried out. Fortunately, recent progress has been remarkable in revealing many possible chemical substances responsible for the mediation of various inflammations which may certainly encourage our experimental studies. Similarly, numerous new findings accumulated by basic immunology may be ready for application to the research about immunologic diseases, including many categories of glomerulonephritis. A modern immunologic aspect may also direct attention towards the immunologic background modulating inflammatory processes. It is expected that these possible future studies, in concert, will contribute to a comprehensive understanding of human glomerular diseases.

Animals↗
PubMed1982

Production of human alpha 1-antichymotrypsin-like protein by a human malignant melanoma transplanted into nude mice.

A tissue culture line of a human malignant melanoma, SEKI, induced cachexia in nude mice (BALB/c-nu/nu) (Kondo et al., Cancer Res., 41: 2912-2916, 1981). During the investigation of the cause of the cachexia, the melanoma was found to produce a protein immunologically identical to human alpha 1-antichymotrypsin (alpha 1-Ach). Tissues of the SEKI melanoma contained the protein immunologically equivalent to 0.29 +/- 0.11 (S.D.) mg of human alpha 1-Ach per g of wet tissue, while the other six human malignant tumors transplanted into nude mice did not contain a detectable amount of it. In the serum of nude mice bearing the melanoma, this protein appeared soon after the tumor growth occurred and gradually increased up to the level equivalent to 5 mg of human alpha 1-Ach per dl. Removal of the tumor resulted in a rapid decrease of the protein in the serum to an undetectable level within 1 day. This problem was never detected in the serum of nude mice bearing the other 27 human malignant tumors or controls. Purification of this protein was carried out by the column chromatography using DE-52, Blue-Sepharose, and SP-Sephadex. The elution patterns were the same as those of alpha 1-Ach in human serum, and the molecular weight of the protein was estimated as 69,000 by Sephadex G-100 column chromatography and 65,000 by polyacrylamide gel electrophoresis with sodium dodecyl sulfate. This purified protein, however, did not exhibit inhibitory activity against chymotrypsin. These results show that this melanoma produced a protein immunologically identical and physicochemically very similar to human alpha 1-Ach. This melanoma-nude mouse system may provide a useful model for investigating the synthesis of human alpha 1-Ach and analysis of its physiological roles.

Animals↗
PubMed1982

Chronic Masugi nephritis in the rat. An electron microscopic study on evolution and consequences of glomerular capsular adhesions.

Chronic focal glomerulonephritis was induced in the rat by using goat nephrotoxic IgG. In the later stage (6 to 15 months) a number of glomeruli were found to be attached to Bowman's capsule with variable segmental sclerosis and/or hyalinosis. The morphogenesis of the changes was studied by electron microscopy. It was found that partial cytoplasmic necrosis of podocytes was an initiating event of the capsular adhesion. When this occurred in the peripheral tufts, the denuded portion of the glomerular basement membrane (GBM) became attached to the parietal epithelium, resulting in progressive thickening of the mesangium and GBM, deposition of hyaline or proteinaceous material, and desquamation of the endothelial sheet, the features being compatible with segmental glomerular sclerosis and/or hyalinosis. It seemed that these changes, in turn, accelerated podocyte desquamation and extension of the capsular adhesion, producing a progressive cycle that terminated in global glomerular hyalinosis. Such a sequence of events most often occurred in rats with massive proteinuria, suggesting that persistent, severe proteinuria caused the podocyte lesion which led to the development of segmental glomerular sclerosis and/or hyalinosis.

Animals↗
PubMed1981

Biliary cystadenocarcinoma with peritoneal carcinomatosis.

An autopsy report of a patient with a hugh biliary cystadenocarcinoma arising in the right lobe of the liver is presented. The tumor had been though to be benign, but peritoneal carcinomatosis developed 18 months after the operation. Autopsy revealed marked peritoneal dissemination of mucinous adenocarcinoma, apparently a result of peritoneal seeding of hepatic cystadenocarcinoma, which was presumed to be triggered by cyst aspiration performed during the operation. Experience indicates that surgical procedures on cystic liver disease should be carried out carefully, considering the possible existence of malignancy.

Adenocarcinoma, Mucinous↗
PubMed1981

Role of tryptophanyl and tyrosyl residues of flavoproteins in binding with flavin coenzymes. X-ray structural studies using model complexes.

The crystal structures of 7,8-dimethylisoalloxazine-10-acetic acid-tryptamine (1:1) tetrahydrate and 7,8-dimethylisoalloxazine-10-acetic acid-tyramine (1:1) tetrahydrate complexes were determined by the X-ray diffraction method, as models for flavin-tryptophan and flavin-tyrosine interactions in flavoproteins. The observed parallel stackings and the intermolecular spacing distances, which were less than the normal van der Waals separation between the isoalloxazine and indole rings and between the isoalloxazine and phenol rings, suggest the existence of charge-transfer interactions in their ground states. The indole and phenol rings interact with the pyrimindinoid and pyrazinoid portions of the isoalloxazine ring and have short contacts, less than 3.4 A, with the reduction site (N1 and N5 atoms) of this ring. This suggests that the reduction of oxidized flavin to the semiquinone state may be facilitated by charge transfer from the former rings to the N1 and N5 atoms. Absorption difference spectra showed that both complexes associate with equimolar ratios in solution as well as in the crystalline state and that they have the same charge-transfer bands and association constants as flavin mononucleotide (FMN)-Trp and FMN-Tyr complexes, respectively. On the other hand, proton magnetic resonance spectra suggested that in solution, the stacking modes of the indole and phenol rings to the isoalloxazine ring are different from those observed in the crystal structures and both aromatic rings are stacked over the whole of the isoalloxazine ring.

Animals↗