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Y Ueda

Publications and source records attributed to Y Ueda.

At least 991 records · Page 55Linked to original sources

[Insulin receptors in fat tissue of human and rat during pregnancy].

Insulin receptors in fat cell membranes (10(5)g pellets) were investigated by a conventional incubation method in pregnant and nonpregnant rats or women. Insulin binding in pregnant L20 rats was 8.1 +/- 2.1% (M +/- SD) less than that in nonpregnant rats (14.5 +/- 3.5%) in peripheral adipose tissues (p less than 0.05). In the former a reciprocal rise in the serum insulin level was observed. In pregnant women, insulin binding was determined in subcutaneous fat tissues obtained at cesarean section or other laparotomy. Insulin binding was 29.3 +/- 8.9% in nonpregnant women, and it did not change in early pregnancy (34.3 +/- 6.2%, NS). However, it decreased obviously in late pregnancy (20.4 +/- 6.4%) (p less than 0.05). Scatchard analysis indicated that the decrease in insulin binding was due to the changes in the number of insulin receptors in fat cell membranes. Their Kd values were indistinguishable from each other in rats and women. In addition, insulin binding correlated significantly with Insulin Sum, Glucose Sum at 75g OGTT, TG and FFA in serum. These results suggested that insulin receptors in adipose tissues were suppressed in late pregnancy, and this might be the cause of the "insulin resistance" observed in the maternal body in late pregnancy.

Adipose Tissue↗

[Insulin receptors in pregnant nonobese diabetic (NOD) mice].

The dynamics of insulin receptors was investigated in the feto-placenta-maternal system of DM-onset pregnant nonobese diabetic (NOD) mice. Insulin binding experiments were carried out by conventional incubation methods using cell membrane fractions (10(5) X g pellets). The results were as follows. In the case of JCL-ICR mice, used as the control, insulin specific binding in liver cell membranes, which was 26.6 +/- 3.2% in the nonpregnant state, decreased in late pregnancy (20.7 +/- 2.7%). On the other hand, in pregnant NOD mice hepatic insulin binding was 24.3 +/- 1.0%, more than that of JCL-ICR pregnant mice. By Scatchard analyses, these changes were found to be due to the changes in the number of receptors especially in high affinity sites. The serum insulin level was 6.3 +/- 4.2 microU/ml in pregnant NOD mice, which was much lower than that in other mice (nonpregnant JCL-ICR: 14.8 +/- 6.4, pregnant JCL-ICR: 37.3 +/- 18.3). In fetal liver and carcasses of NOD fetuses, insulin binding was also much greater than that in JCL-ICR fetuses. In conclusion, the hormone sensitivity to insulin was accentuated in pregnant DM-onset NOD mice not only in the maternal body but also in the fetus. This is regarded as a metabolic adaptation to the environment in the insulin deficient state of these mice. And it is speculated that insulin receptors are also down-regulated in fetal liver as well as in adult mice.

Animals↗

Characterization of T lymphocyte subpopulations responsible for deficient interleukin 2 activity in patients with systemic lupus erythematosus.

Normal immunoregulation depends on a complex set of cellular interactions in which interleukin 2 (IL 2) appears to play an important role. We have examined the IL 2 activity in patients with systemic lupus erythematosus (SLE). IL 2 production by phytohemagglutinin (PHA)-stimulated T cells for 48 hr was measured by the ability of their culture fluid to induce proliferation of normal human T cells that had been activated for more than 20 days by PHA plus IL 2. To measure IL 2 responsiveness, T cells were blasted by preincubation with concanavalin A for 96 hr and stimulated for another 72 hr with lectin-free standard IL 2. SLE T cells failed to produce normal levels of IL 2 in vitro compared with normal control T cells. This failure resided in both OKT4+ and OKT8+ cells. Furthermore, the abnormality was due neither to soluble inhibitory factors produced by SLE T cells nor to active suppressor cells that might be induced by PHA-stimulation. Responsiveness to IL 2 of T cells from some, but not all, SLE patients was decreased significantly from that of normal controls. Absorption studies as well as studies with anti-Tac antibody demonstrated that the impaired responsiveness of T cells in the specific patients with SLE was due to inadequate expression of IL 2 receptors on the T cells upon activation. This defect was exclusively ascribed to the dysfunction of OKT4+, but not OKT8+, cells. The above defects in production of and responsiveness to IL 2 observed in patients with SLE were present at all times regardless of the disease activity or of corticosteroid therapy. Thus, the deficient IL 2 activity may be intrinsic to SLE lymphocytes and may contribute to impaired immunoregulation and to the development of SLE.

Adult↗

OKT4+ and OKT8+ T lymphocytes produce soluble factors that can modulate growth and differentiation of human B cells.

The human T cell subset(s) responsible for the production of soluble factors that can modulate B cell growth and B cell differentiation was investigated in the present study. For this purpose, highly purified OKT4+ and OKT8+ lymphocytes were stimulated with phytohaemagglutinin and phorbol myristate acetate. Subsequently, culture supernatants were analysed for B cell growth factor (BCGF) activity and B cell differentiation factor (BCDF) activity in the following systems: 1) maintenance of a proliferative state of Staphylococcus aureus of strain Cowan I (SAC)-stimulated B cells and 2) induction of plaque-forming cell responses of SAC-stimulated B cells. Mitogenic stimulation led to production of equivalent amounts of either BCGF activity or BCDF activity from both of the OKT4+ and OKT8+ subsets. These findings may provide a basis for further studies of the molecular mechanisms as well as cellular interactions involved in human B cell activation, proliferation and differentiation.

Adult↗

[A case report of tubular adenoma of the breast].

Pure adenoma of the breast was seen in a 34-year-old Japanese woman. On examination, there was a firm, movable, nontender mass, 2.0 cm in diameter, in the upper outer quadrant of the left breast. The xeromammographic and macroscopical diagnosis was fibroadenoma. Histological examination, however, identified pure tubular adenoma of the breast. This was reported herein because of its extreme rarity.

Adenofibroma↗

[Clinical studies on the effectiveness of SM-4300, a new non-modified gammaglobulin preparation suitable for intravenous use, in refractory infections].

Eighteen cases of various infections, mostly having severe underlying diseases and showing no or insufficient responses to antibacterial chemotherapy, were treated with additional intravenous drip infusion of SM-4300 (2.5 or 5 g, once a day, for 1-3 days). Eight of the cases were excluded from the assessment of the effectiveness, as they died too early, or as their fever was supposed to have been "tumor fever" retrospectively. SM-4300 was found to be effective in 2 out of 5 septicemia cases, in 3 pneumonia cases, including 1 complicated with septicemia, out of 4, and also in 1 patient with liver abscess, as well as in another of meningitis caused by Campylobacter fetus; i.e. the efficacy rate was estimated as 60% in total. Any side effects attributable to SM-4300 were observed in none of the 18 cases. These results obtained seem to endorse the usefulness of the preparation.

Adolescent↗