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Biomedical subjects

M Tsuchiya

Publications and source records attributed to M Tsuchiya.

At least 649 records · Page 36Linked to original sources

Adult human autoimmune thymus transplantation into nude mice - functioning of human thymus epithelium in nude mice.

Thymuses from patients with autoimmune disease were transplanted into nude mice. The thymus transplants survived for over 40 days and evidence of restoration of thymic function was observed. The de facto loss of human thymocytes from the implanted tissue resulted in an in vitro culture of pure thymus epithelium. The results suggest that adult human autoimmune thymus has the functional ability to restore immunocompetence for a thymusless mouse, and that human "thymic hormone" is a substance which does not have species specificity. This new approach to the functional activity of thymus epithelium may also be useful for a study in the pathogenesis of autoimmune disease.

Adult↗

In vitro culture of thymic epithelial cells from various autoimmune diseases: its thymosin-like effect on human peripheral lymphocytes.

We succeeded in the culture of the thymic epithelium which obtained from the patients with various autoimmune diseases aged from 20 to 65 years whose thymuses should have already been involuted with decreased thymic function. The mean percentage of active rosette-forming cells significantly increased after the incubation with thymic monolayer culture medium. These observations suggest that thymic epithelia in autoimmune diseases produce thymosin-like factor(s) in culture medium.

Adult↗

HLA antigens and myasthenia gravis in Japan.

Recent studies have noted an increased association of the histocompatibility antigen HLA-B8 with myasthenia gravis in Caucasian patients. The HLA types of 63 Japanese patients with myasthenia were compared to those of 271 controls. The present study was designed to assess correlations between HLA antigens, sex, age at onset, the presence of autoantibodies and thymic morphology. HLA-B12 was increased Japanese patients, especially females with early age at onset, and in addition it was significantly correlated with thymic hyperplasia. HLA-B5 was frequently found in the patients with thymoma. Statistically the most frequent haplotype found in this disease was HLA-A10-HLA-B12.

Adult↗

Systemic hemodynamic effects of microspheres in conscious rats.

The effect of increasing quantities of carbonized microspheres (15 +/- 5 micrometer diam) on systemic hemodynamics was evaluated in 21 Sprague-Dawley, 6 normotensive Wistar-Kyoto (WKY), and 8 spontaneously hypertensive (SHR) male rats. Total cumulative injections of more than 100,000 microspheres produced significant systemic hemodynamic alterations manifested by decreased oxygen consumption, cardiac output, and mean arterial pressure; and by increased heart rate, total peripheral resistance, and arterial-venous blood oxygen content difference. There were no hemodynamic alterations characteristic of any rat species, and reproducibility of three separate injections of 20,000 microspheres in each rat was excellent.

Animals↗

HLA antigens and ulcerative colitis in Japan.

The HLA antigens in 44 cases of ulcerative colitis and 271 control individuals in Japan were studied. The NIH tissue typing method was used according to the new leukocyte nomenclature adapted by the WHO Committee. In normal Japanese populations, the HLA antigens, which were of high frequency, were HLA A2(37.3%), A9(60.9%) and B5 (40.6%). On the contrary, the significantly high frequency of HLA B5 was demonstrated in ulcerative colitis, compared with that in control. Moreover, HLA B5 in cases with ulcerative colitis excluding those with proctitis only, was found with higher frequency than that in total cases. Although the most frequent haplotype was HLA A9-B5 in control, so frequent haplotype was not found in ulcerative colitis. A family study revealed no significant diathesis on the hapolytpe of HLA in ulcerative colitis. The relationship between MLC locus and ulcerative colitis was not yet clarified from the study of one family whose two members suffered from ulcerative colitis.

Adult↗

Effects of Panax Ginseng root on conditioned avoidance response in rats.

Pole climbing and shuttle box tests were employed to study conditioned avoidance response (CAR) and discrimination behaviour in Wistar male rats given extracts from Panax Ginseng root intraperitonealy. Neutral saponins (GNS), a water soluble fraction (GF4) which does not contain saponins, and a lipid soluble fraction (GNo. 5) inhibited CAR and discrimination ability between 500 Hz sound with electric shock (SD) and 1000 Hz sound without shock (Sdelta). Small doses of GNo. 5 and ginsenoside Rg fraction (GRg) produced a slight shortening of the response latency (RL) to the conditioned stimulus in CAR. GNo. 5 produced the incorrect response to Sdelta. Significant changes in the extinction of CAR were not evident with any fraction. Data from these tests indicate that Panax Ginseng root contains at least three sedative compounds.

Animals↗

[Electron microscopic study of the small intestine in intestinal lymphangiectasia and constrictive pericarditis (author's transl)].

Electron microscopic study of the small intestine in cases of intestinal lymphangiectasia and in cases of constrictive pericarditis was performed. This study revealed that numerous chylomicron-like particles are present in the lymphatic lumina, in the extracellular spaces of the lamina propria, and within the interepithelial spaces between the absorptive cells. Presence of chylomicron-like particles in the intestinal lumen suggested possibility of passage of these substances into the intestinal tract through the interepithelial spaces. Similar findings to those as seen in intestinal lymphangiectasia were observed in constrictive pericarditis. A few pseudopode-like cytoplasmic projections of the undifferentiated crypt cells were noted. Other mechanisms of enteric protein loss are postulated.

Chylomicrons↗