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Biomedical subjects

H Takeda

Publications and source records attributed to H Takeda.

At least 505 records · Page 28Linked to original sources
PubMed1988

Effect of alpha 2-adrenoceptor antagonist on platelet activation during insulin-induced hypoglycaemia in type 2 (non-insulin-dependent) diabetes mellitus.

The role of epinephrine in platelet activation and the effect of an alpha 2-adrenoceptor antagonist, midaglizole, during insulin-induced hypoglycaemia in Type 2 (non-insulin-dependent) diabetes mellitus were examined. The action of midaglizole as a platelet alpha 2-antagonist was confirmed by in vitro studies using platelet-rich plasma and washed platelet suspension. Hypoglycaemia was induced by a bolus injection of short-acting insulin in 24 diabetic patients. They were divided into two groups, a control group (n = 12) and an alpha 2-group (n = 12), and midaglizole was administered orally 60 min before insulin injection in the latter. Blood glucose and plasma C-peptide levels were significantly decreased (p less than 0.005) by insulin injection in both groups. Counter-regulatory hormones, including epinephrine, and arginine vasopressin were similarly increased at the hypoglycaemic nadir compared with the levels at 0 min in both groups. Plasma beta-thromboglobulin was increased at the hypoglycaemic nadir (165.5 +/- 12.6 ng/ml) compared with the level at 0 min (121.0 +/- 11.5, p less than 0.005) in the control group, whereas no significant increase was demonstrated in the alpha 2-group. These results suggest that plasma epinephrine plays an important role in platelet activation during hypoglycaemia in Type 2 diabetes mellitus, and that the platelet activation is prevented by alpha 2-adrenoceptor antagonist.

Arginine Vasopressin↗
PubMed1988

Three cases of afferent loop obstruction--the role of ultrasonography in the diagnosis.

Three cases of obstruction of the afferent loop following a Billroth II type gastrectomy were preoperatively detected by ultrasonography. The obstructions in the 3 patients were caused by volvulus, internal herniation and recurrence of gastric cancer, respectively. The important US findings which helped diagnose this condition were a dilated intestinal loop without gas echo in the upper abdominal cavity and echo lucent swelling of the pancreas. Ultrasonography is very useful for the early and easy detection of this life-threatening condition which requires immediate surgery.

Afferent Loop Syndrome↗
PubMed1988

Effect of interleukin 1 and interleukin 2 on antibody production in asymptomatic hepatitis B virus (HBV) carriers.

Peripheral blood mononuclear cells from asymptomatic hepatitis B virus (HBV) carriers and healthy controls were incubated with recombinant interleukin 1 (r-IL1) or recombinant interleukin 2 (r-IL2) at 37 degrees C for 24 hours and with pokeweed mitogen (PWM) and estradiol for 72 hours. The number of antibody-producing cells was counted by hemolytic plaque assay. When the mononuclear cells were not pretreated with r-IL1 or r-IL2, the number of antibody-producing cells was not increased by estradiol in asymptomatic HBV carriers. However, when the mononuclear cells were pretreated with r-IL1 or r-IL2, the number of antibody-producing cells was increased. As we have reported before, this may be have been due to the increase in the estradiol-binding capacity of the mononuclear cells by treatment with IL1 and IL2. In asymptomatic HBv carriers, IL1 and IL2 production of the mononuclear cells or the response of the mononuclear cells to IL1 and IL2 is reduced. Consequently, the estradiol binding capacity is decreased, and antibody production is not increased by estradiol.

Antibody Formation↗
PubMed1988

Sensitivity and accuracy in recording His-Purkinje activity by surface-averaged electrocardiography.

A clinical evaluation of the surface-averaged ECG (SAE) to record His-Purkinje activity (HPA) was made on 70 patients who underwent His bundle electrograms (HBE). The recorded signals first judged as HPA in 43 patients by the noninvasive method alone were later verified in 37 patients by HBE; the accuracy of the HPA recordings (predictive value) was 86.0%. The HPA-V interval measured noninvasively had a high correlation with the HV interval by HBE (r = 0.89, p less than 0.01). The verified detection rate in all 70 patients was 52.9%: HPA was detected in 12 of 18 patients (66.7%) with sclerotic and hypertensive heart disease (Group I), five of 19 patients (26.3%) with rheumatic heart disease (Group II), 11 of 17 patients (64.7%) with congenital heart disease (Group III), and nine of 16 patients (56.2%) with miscellaneous conditions (Group IV). The detection rate was markedly lower in Group II than in other groups (Group II vs Group I or III, p less than 0.025). The PR segment was significantly longer in the patients in whom HPA was detected than in those in whom it was not detected (71.5 +/- 22.3 msec vs 43.9 +/- 19.5 msec, p less than 0.001). His-Purkinje activity (HPA) was detected in 32 of 52 recordings (61.5%) with sinus rhythm and seven of 20 recordings (35.0%) with atrial fibrillation, including two recordings in each of two cardioverted patients (p less than 0.05). We conclude that the surface-averaged ECG (SAE) has clinically acceptable sensitivity and accuracy except in patients with rheumatic heart disease, short PR segments or atrial fibrillations.

Atrial Fibrillation↗
PubMed1988

Immunofluorescent localization of tenascin during development of the mouse urogenital sinus: possible involvement in genital duct morphogenesis.

Tenascin is a compound of the mesenchymal extracellular matrix and has been proposed as a possible mediator in epithelial-mesenchymal interactions, because of its characteristic distribution in tissues during fetal development. In the present study, we have investigated by immunofluorescence the changes in the distribution of tenascin during development of the mouse urogenital sinus, a process in which tissue interactions were found to be essential. Tenascin first appears in dorsal mesenchyme on days 13-15 of gestation, coinciding with morphological changes of the epithelium. During male development, tenascin accumulates in the dorsal mesenchyme around the junction of Wolffian ducts, but not in the ventral mesenchyme, into which prostatic buds (prostate gland anlagen) project from the sinus epithelium. During female development, the mesenchyme that participates in the downgrowth of the vagina (derived from Müllerian ducts) stains intensively for tenascin. In both of these tenascin-positive areas, the epithelium undergoes conspicuous morphogenetic changes. The results suggest that mesenchymal tenascin could be involved in the epithelial morphogenesis of the sinus, especially in the morphogenesis of the genital ducts.

Animals↗
PubMed1988

Intracellular Ca2+ shift and signal transduction from the tubulovesicular portion of gastric parietal cells during gastrin stimulation or Ca2+ ionophore treatment: comparison between luminescent and fluorescent probes, and electron probe X-ray microanalyzer.

In gastrin-stimulated, aequorin-loaded parietal cells from guinea pig gastric mucosa, a rapid but transient increase in the cytosolic free Ca2+ concentration ([Ca2+]i), owing to Ca2+ released from the store(s), and a more prolonged Ca2+ entry from outside the cells were observed. However, there was a little increase in [Ca2+]i when similar measurements were assessed by quin 2 or fura-2 in physiological saline. However, depletion or elimination of Na+ from the incubation medium caused a significant increase in the [Ca2+]; response to gastrin as measured by quin 2. These findings suggest that aequorin and quin 2 (or fura-2) provide information about different aspects of Ca2+ homeostasis and that there is an inhomogeneity of [Ca2+]i in the cytoplasm during gastrin stimulation. By the gastrin stimulation, the intracellular Ca2+ gradients were shifted from the unidentified portion(s) to the restricted apical cytoplasm, as determined by electron probe X-ray microanalysis. Therefore, localization and identification of the source of intracellular Ca2+ as a pool were determined by an X-ray microanalyzer. In the resting state, the tubulovesicle had high Ca2+ concentration compared with the level in the apical cytoplasm. Cells treated with the Ca2+ ionophore ionomycin had a decreased tubulovesicular Ca2+ level, followed by a reciprocal increase in area of the canalicular membrane. The secretory canaliculus in stimulated cells had lower Ca2+ or higher K+ and Cl- concentrations than that of tubulovesicles or cytoplasm in the resting state, respectively. These findings suggest that the Ca2+ pool of the parietal cell is in the tubulovesicles and (or) luminal cell membrane and that the Ca2+ released from the store(s) may mediate a flow of K+ or Cl- into the secretory canaliculus.

Aequorin↗
PubMed1988

Effect of pre-exercise fructose ingestion on endurance performance in fed men.

Twelve trained males, in a fed state, were studied to examine the effect of pre-exercise fructose ingestion on endurance capacity during prolonged cycling exercise. Sixty minutes prior to exercise, subjects ingested either 60 or 85 g fructose or a sweet placebo. Mean exercise intensity initially required 62% of the maximal aerobic power and thereafter increased to elicit 72 and 81% of maximal aerobic power at 90 and 120 min of exercise, respectively. Exercise time (mean +/- SE) to exhaustion was significantly increased after fructose ingestion, as compared to placebo ingestion (145 +/- 4 vs 132 +/- 3 min, P less than 0.01). During the exercise, no differences were observed between both trials for oxygen uptake, heart rate, or perceived exertion. Serum glucose and insulin levels between both trials were not significantly different throughout the experiment. There were also no significant differences in serum-free fatty acids and glycerol levels as well as respiratory exchange ratio between fructose and placebo trials during the exercise. The results suggest that fructose ingestion is of benefit before prolonged exercise, because it provides a carbohydrate source to contracting muscles without transient hypoglycemia and a depression of fat utilization, and thereby delays the fatigue.

Adolescent↗
PubMed1988

Impairment in the response of peripheral blood mononuclear cells from asymptomatic hepatitis B virus carriers to estradiol.

Sex hormones are known to affect the immune system. Asymptomatic hepatitis B virus (HBV) carriers are thought to be immunologically tolerant to HBV, but in some HBV carriers, the immune response to HBV is induced, especially in females during their sexually-mature periods. This may be caused by the effects of estrogens on the immune system. In this study, we found that the level of estradiol receptors in the cytosol of peripheral blood mononuclear cells was significantly lower in asymptomatic HBV carriers compared to healthy controls. This suggests that in asymptomatic HBV carriers, antibody production of peripheral blood mononuclear cells was lower compared to that of healthy controls as a result of the low level of estradiol receptors.

Carrier State↗
PubMed1988

Ethyl eicosapentaenoate restored the immunosuppression in mice fed fat-free diet.

The effects of eicosapentaenoic acid (EPA) on the humoral immune response in fat free diet-fed (FF) mice were studied. The lowered anti-SRBC PFC activity of ICR male FF mice was restored in a dose-dependent manner when EPA was administered orally at doses of 60-360 mg/kg/day for 20 days. In in vitro experiments, EPA similarly enhanced anti-SRBC PFC activity but did not affect the response against lipopolysaccharide. Furthermore, EPA did not cause any substantial effect on T suppressor cell activity induced by Concanavalin A in vitro. On the other hand, T helper cell activity induced by keyhole limpet hemocyanin was augmented. From these results, it is suggestive that EPA caused immunopotentiation to FF mice at least partially by an enhancement of T helper cell activities.

Animals↗