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Biomedical subjects

T Kameda

Publications and source records attributed to T Kameda.

149 records · Page 9Linked to original sources

Localization of three subtypes of Fc gamma receptors in human placenta by immunohistochemical analysis.

We investigated the localization of the three subtypes of (Fc gamma R) in the normal human placenta using immunohistochemical and immunocytochemical techniques with specific monoclonal antibodies. The analysis revealed that Fc gamma RI was expressed on Hofbauer cells, that Fc gamma RII was expressed on Hofbauer cells and endothelial cells of fetal vessels, while Fc gamma RIII was expressed on trophoblasts, especially syncytiotrophoblasts. Moreover, we demonstrated that the expression of Fc gamma RI and Fc gamma RII on Hofbauer cells and endothelial cells of the fetal vessels in the 1st trimester placenta was different from that in the 3rd trimester placenta. These results, therefore, indicate that the three subtypes of Fc gamma R in the human placenta may contribute to maintenance of placental functions, because each Fc gamma R molecule displays unique biological functions similar to those on leukocytes.

Animals↗

Production of interleukin-6 by normal human trophoblast.

The placenta plays a number of important roles during pregnancy, some of which might be mediated by cytokines with multiple activities such as IL-6. Using an IL-6-dependent cell line, MH6o.BSF2, we showed that the placenta released IL-6 into the culture supernatant. Analysis of single-cell suspensions of placental cells determined the major source of IL-6 to be trophoblast. Using a mouse monoclonal antibody specific for IL-6 (alpha BSF2-I66), immuno-histochemical analysis of placental specimens demonstrated the localization of IL-6 only in the trophoblast layer. Additional immunocytochemical studies with single-cell suspensions of trophoblasts demonstrated the preferential presence of IL-6 molecules in syncytiotrophoblasts rather than cytotrophoblasts. The evidence that a high titer of IL-6 is produced spontaneously by syncytiotrophoblasts indicates that IL-6 may play immunological roles in fetomaternal interactions by means of IL-6-driven multiple immunoregulatory activities.

Cells, Cultured↗

Coronary-coronary bypass using the internal thoracic artery: a sparing procedure of the arterial conduit.

BACKGROUND: The internal thoracic artery (ITA) is well known to be the best conduit for coronary artery bypass grafting. However, the bilateral use of ITAs remains limited because in situ right ITAs (RITAs) do not possess an adequate length to be directed to the posterolateral myocardium. We thus considered using free ITAs for conduits between the two segments of the same coronary artery. METHODS: From March 1997 to May 1999, 17 patients underwent coronary-coronary bypass grafting (C-CBG) using free ITAs. Early operative results were analyzed. C-CBG was indicated when the right ITA had an inadequate length or when a distal part of the ITA was left unused. RESULTS: No patient died after C-CBG and none have experienced angina since C-CBG (mean follow-up period 27.3 +/- 19.8 months). Postoperative angiography was performed in all subjects at discharge. Only one coronary-coronary bypass graft was occluded, the other grafts were patent, and there were no stenotic changes. Bilateral ITAs were used in 75% of the patients undergoing CABG during the period of this study. CONCLUSIONS: C-CBG can expand the use of bilateral ITAs and can provide an alternative method for revascularization of the posterolateral myocardium.

Adult↗

Haemopathological changes in recurrent deep venous thrombosis of the extremities.

We observed 42 (11.7%) patients with multiple or recurrent thrombosis in 358 patients with deep venous thrombosis of the extremities (DVT) and its sequelae. In those patients with recurrent DVT, following characteristics were found in comparison with patients with recurrent DVT, following characteristics were found in comparison with patients who experienced only one episode of DVT. Collagen disease including Behçet disease are often observed as an important predisposing factor. Relatively high incidence in the young generation. Pulmonary embolism occurred about 4 times as frequent as in patients with single episode of DVT. The platelet adhesiveness increased in 7 (38.9%) cases and the hyperaggregability was also frequently found (34.8% by ADP, 26.1% by collagen), though no significant differences was noted from patients with single episode of DVT. Meanwhile, beta-thromboglobulin increased an antithrombin III decreased with a significant difference. DVT with those characteristics should more carefully be managed.

Adolescent↗