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Biomedical subjects

H Shibata

Publications and source records attributed to H Shibata.

At least 469 records · Page 26Linked to original sources
PubMed1991

Involvement of protein kinase C in angiotensin II-mediated release of 12-hydroxyeicosatetraenoic acid in bovine adrenal glomerulosa cells.

The present study was conducted to determine whether protein kinase C was involved in angiotensin II-mediated release of 12-hydroxyeicosatetraenoic acid (12-HETE) from bovine adrenal glomerulosa cells. Activators of protein kinase C, 12-O-tetradecanoylphorbol 4-acetate (TPA) and 1-oleoyl-2-acetylglycerol (OAG), significantly increased release of 12-HETE. The effect of OAG was potentiated by BAYK8644, a stimulator of calcium entry. Sphingosine, H-7 and staurosporine, which inhibited the activity of protein kinase C in vitro, almost completely blocked 12-HETE release induced by TPA. These agents also significantly reduced angiotensin II-mediated 12-HETE release. When time course of the liberation of 12-HETE was measured, angiotensin II elicited sustained release of 12-HETE, which was inhibited by staurosporine. These results indicate that angiotensin II induces sustained release of 12-HETE, a feed forward regulator of aldosterone secretion, and that protein kinase C may be involved in this process.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1991

Blood clearances of 99mTc-phytate and indocyanine green in carbon tetrachloride treated dogs.

The comparative study of the blood clearances of 99mTc-phytate (99mTc-P) and indocyanine green (ICG) was carried out in dogs with hepatic injury induced by carbon tetrachloride (CCl4), and the blood clearance of 99mTc-P or ICG was compared with the levels of serum transaminase and bilirubin. The blood clearances of 99mTc-P and ICG in dogs decreased with increase in doses of CCl4 and with elapsed time after CCl4 administration. The decreases were correspondent to the increase in serum transaminase activity and bilirubin level. The blood clearance test of 99mTc-P in dogs showed a equal degree of sensitivity and a higher degree of accuracy for the acute hepatic dysfunction induced by CCl4 as compared with the blood clearance test of ICG.

Alanine Transaminase↗
PubMed1991

Effects of acupuncture on immune response in mice.

The effect of acupuncture points stimulation on the induction of plaque-forming cells (PFC) in spleen cells of BALB/c mice was investigated in vivo and in vitro tests. In in vivo experiment, mice were immunized with 2 x 10(8) sheep red blood cells (SRBC) and the PFC was markedly increased by daily (once a day for 4 days) acupuncture stimulation. The enhancement of PFC by acupuncture was completely blocked by preadministration of procain, hexamethonium, naloxone, propranolol, but not by phentolamine. The enhancement of PFC by acupuncture was also observed in spleen cells of non-immunoized mice when spleen cells of the acupunctured mice were cultured with SRB in vitro. The enhancement of PFC in spleen was observed after stimulation with acupuncture, and a similar effect was also found in bone marrow cells of normal mice, but not in thymic cells. The spleen cells of mice given acupuncture showed no enhancement of PFC after treatment with anti-Thy 1.2 antibody and complement. Furthermore, these helper T cells were found to be not restricted by the H-2 gene complex. These data demonstrate that the helper T cells induced by acupuncture lack the H-2 restriction, and thus suggest that they may be drived from the bone marrow, but not from the thymus. It is therefore concluded that the helper T cells derived from the bone marrow were activated via the sympathetic nervous system stimulated by acupuncture.

Acupuncture Therapy↗
PubMed1991

Immunological and behavioral effects of fragrance in mice.

The aim of this study was to determine the effects of olfactory stimulation on immunological and behavioral states in mice. Anti-SRBC (IgM) plaque forming cell (PFC) count and spontaneous running activity (SRA) were measured to demonstrate the effects of exposure to a given fragrance. The decreased PFC count and thymic involution induced by high pressure stress in mice were recovered after exposing the stressed mice to the fragrance continuously for 4 days after the stress was given. The PFC and SRA also appeared to be maintained at normal levels by oflactory stimulation with the fragrance for 24 hrs after the given stress. The immunological suppression induced by high pressure stress was considered to be caused by the induction and activation of suppressor cells. However, exposure to the fragrance after the stress did not enhance suppressor activity. The restoration of the stress-induced immune suppression by olfactory stimulation was blocked by procain administration onto the olfactory cells.

Animals↗
PubMed1991

Synthesis and inhibitory activity of acyl-peptidyl-pyrrolidine derivatives toward post-proline cleaving enzyme; a study of subsite specificity.

Several pyrrolidine derivatives have been synthesized and examined for their inhibitory activity on post-proline cleaving enzymes from Flavobacterium meningosepticum and bovine brain. Almost all the compounds tested in this study inhibited the activity of both enzymes at low IC50 values (from nM to microM) but a specificity difference was observed with alkylacyl-peptidyl-pyrrolidine derivatives which strongly inhibited only the bacterial enzyme. The most effective inhibitors have a proline residue on their P2 sites and a substituted or unsubstituted phenoxybutyryl moiety on their P3 sites. Thus phenoxybutyryl-prolyl-pyrrolidine is the most effective partial structure of the inhibitors. The best inhibitors found were: 4-(4-benzylphenoxy)butyryl-prolyl-pyrrolidine for bacterial enzyme (IC50 1.4 nM) and 4-phenylbutyryl-thioprolyl-pyrrolidine for bovine brain enzyme (IC50 67 nM). In the passive avoidance test, using amnesic rats experimentally induced with scopolamine, the pyrrolidine derivatives which had potent inhibitory activity toward post-proline cleaving enzymes also showed strong anti-amnesic activities at doses of 1-5 mg/kg, i.p.

Acylation↗
PubMed1991

Intestinal brush border calcium uptake in spontaneously hypertensive rats and their genetically matched WKY rats.

The current studies were designed to characterize calcium transport by intestinal brush border membrane in the spontaneously hypertensive rat (SHR) and normotensive control, the Wistar-Kyoto (WKY) rat. The biochemical and functional purity of the intestinal brush border membranes in SHR and WKY rats was validated by marker enzymes and the ability to transiently transport D-glucose in the presence of Na+ gradient. Calcium transport into duodenal and jejunal vesicles represented a minor binding component and transmembrane movement as evident by initial rate studies, A23187 studies, and lanthanum displacement experiments. Initial rate and time course of calcium uptake was lower in SHR compared with WKY rats. Kinetic analysis of calcium uptake by the jejunum (total uptake minus binding component) showed a Vmax of 6.98 +/- 0.2 and 1.8 +/- 0.2 nmol/mg protein/7 sec in WKY rats and SHR, respectively (P less than 0.001), whereas Km values were 0.76 +/- 0.04 and 0.87 +/- 0.1 mM for WKY rats and SHR, respectively. Similar kinetic analysis of calcium uptake by the duodenal segments showed a Vmax of 10.3 +/- 0.8 and 2.8 +/- 0.2 nmol/mg protein/7 sec in WKY rats and SHR, respectively (P less than 0.01). Km values were 0.7 +/- 0.2 and 0.3 +/- 0.06 mM (P greater than 0.05). Vmax of calcium uptake in the 2-week-old rats (prehypertensive period) was 6.0 +/- 0.3 and 3.53 +/- 0.3 nmol/mg protein/7 sec in WKY rats and SHR, respectively (P less than 0.001), whereas Km values were 0.60 +/- 0.07 and 0.5 +/- 0.01 mM, respectively. These results suggest that calcium binding and uptake by duodenal and jejunal intestinal brush border membranes of SHR is significantly decreased compared with WKY rats. The decrease in transmembrane calcium uptake is secondary to decrease in Vmax and is present before the appearance of hypertension, implying a genetically determined defect in calcium uptake in intestinal brush border membranes of the SHR.

Animals↗
PubMed1991

Hemorrhagic cystitis after bone marrow transplantation: importance of a thin sectioning technique on urinary sediments for diagnosis.

We used a thin-sectioning technique for the electron microscopic detection of viral particles within the cells of urinary sediments in three recipients who developed hemorrhagic cystitis after allogeneic bone marrow transplantation. Results of viral cultures of urine and electron microscopic (EM) observations on urinary sediments were consistent in only one recipient. In this recipient, EM observations revealed many viral particles within the cells of urinary sediments with diameter of about 80 nm corresponding to adenovirus, of which type 11 was produced in viral cultures. In one of the other two recipients many viral particles with a mean diameter of 41.6 nm corresponding to papovavirus were observed, but viral cultures using conventional cells were negative. Re-cultures using HEK cells produced polyomavirus BK. EM observation was a clue to the correct diagnosis. In the remaining recipient, no viral particles were observed within the cells of urinary sediments, suggesting the hemorrhagic cystitis to be of non-viral origin, despite a positive result of viral culture. These results suggest that a thin-sectioning technique on the cells of urinary sediments is important for the differential diagnosis between a viral-induced and non-viral hemorrhagic cystitis.

Adenoviridae↗
PubMed1991

[Treatment of malignant gliomas by selective intraarterial infusion chemotherapy with high-dose ACNU and autologous bone marrow transplantation--preliminary report].

Six patients with malignant gliomas were treated by selective intracarotid infusion of ACNU at 15 mg/kg (about 600 mg per m2) or 10 mg/kg with or without radiotherapy and rescue of autologous bone marrow transplantation after surgery. These high doses of ACNU were well tolerated if bone marrow rescue was performed and granulocyte colony stimulating factor was used. With the development of microcatheters for use in selective intraarterial infusion, it has become possible to cannulate the major artery and infuse drugs at high dose into the artery feeding the tumor. The complication of ocular toxicity can be avoided by using the Tracker-18 or Balt (Magic) angiographic catheter. On the other hand, drug dosage and infusion rate must be chosen carefully, because of the increased likelihood of local arteritis and local necrosis caused by high dosage of ACNU. In the present study, local arteritis or cerebral infarction in the area of the middle cerebral artery was considered to have been prevented by extending the infusion time to 80 minutes. When combined with radiotherapy, 10 mg/kg of ACNU and 80 min. of infusion time were found to be optimal in relation to brain tolerance.

Adolescent↗
PubMed1991

Clinical effect of granulocyte colony-stimulating factor on neutrophils and leukemic cells in myelogenous leukemia: analysis.

Clinical experiences with recombinant granulocyte colony-stimulating factor (rhG-CSF) in 13 acute (AML) and four chronic (CML) myelogenous leukemia patients are reported. Sixteen patients received rhG-CSF in support of treatment for life threatening infections and one CML patient in support of induction chemotherapy. After their first induction chemotherapy, six out of eight AML patients showed a rapid increase of neutrophils, recovered from infections and achieved complete remission (CR). One patient, in whom both neutrophils and blasts had increased during rhG-CSF administration, achieved CR through the next administration of chemotherapy (CR rate 87.5%). The last of the eight AML patients showed no increase of neutrophils, and died of interstitial pneumonitis. Two of five AML patients who received rhG-CSF after reinduction chemotherapy for relapsed or refractory leukemia achieved CR, a rate of 40%. In one of the two, the administration of rhG-CSF prior to induction chemotherapy seemed advantageous in achieving CR. During rhG-CSF administration, an increase of blastic cells in peripheral blood was observed in four out of all 13 AML patients. One of three CML patients, with a lymphoid crisis, showed an increase only of neutrophils, and recovered from infection. The other two showed increases of both neutrophils and blasts. One patient with CML in blastic crisis, undergoing induction chemotherapy with rhG-CSF administration, returned to the chronic phase. These clinical experiences suggest rhG-CSF to be effective in supporting infection therapy and in possibly enhancing the sensitivity of myelogenous leukemic blasts to antileukemic agents.

Adolescent↗
PubMed1991

[Relationship of self-rated health to mortality among the community elderly].

The purpose of the present study is to examine the relationship of self-rated health to mortality. Subjects consisted of 1096 elderly (471 men, 625 women) aged 65 years and over in 1983, living in the town of Yuwa in Akita Prefecture. They were followed to determine survivorship status and relocation for 7 years after the baseline survey in 1983. The relationship of self-rated health to mortality was tested using a logistic model. The results obtained were as follows: (1) Poor self-rated health was significantly related to higher mortality in a graded fashion by univariate analyses. (2) The significant relationship of self-rated health to mortality was still observed after controlling for sex, age, education, drinking, smoking, physician visits, history of stroke, and activities of daily living. (3) The contribution of self-rated health to mortality differed by sex, age group (65-74, 75-), and period of follow-up (early, late). The contribution was greater in men, aged 75 and over, and during the latter part of the follow up.

Aged↗
PubMed1991

[The relationship of chewing ability to nutrient and food intakes in the community elderly].

The purpose of the present study is to investigate the relationship of chewing ability to nutrient and food intakes in the community elderly. Subjects consisted of 145 elderly residents (56 males, 89 females) ranging in age from 65 to 79 years, living at home in a village of Okinawa Prefecture. Chewing ability was divided into two categories: being able to chew ordinary foods was defined as "good", and being able to chew only soft foods as "bad". To determine quantitative food intakes 24-hour dietary records were utilized which were confirmed by nutritionists during interviews. Good chewing ability was found in 82.1% for males and 83.1% for females with no statistically significant difference concerning age or sex. Teeth status was significantly related to chewing ability. For both males and females, protein intake was lower in the group with bad chewing ability than in the good group. Only in males intakes of total energy, fats, Ca, and Fe were lower in the group with bad chewing ability. Concerning food items, intakes of dark green and yellow vegetables and fat in males, and intake of rice in females, were lower in the group with bad chewing ability.

Aged↗
PubMed1991

[Incidence of and circumstances related to falls among the elderly in a Japanese community].

In order to determine incidence of and the circumstances related to falls among the elderly in a community in Japan, general health surveys were carried out in 1988 and in 1989. Subjects for the first survey were 685 elderly residents (276 men, 409 women) aged 65 years and over, living in a rural village of Akita Prefecture. Subjects who were confined to bed almost all day were excluded from analysis. Subjects were interviewed regarding falls at both surveys. Results obtained were as follows; 1) Incidence of falls were 19.2% for men, and 20.3% for women at the first survey. There was no significant difference in incidence between sexes. 2) Age had no significant effect on incidence in either sex. 3) The incidence at the follow-up survey was significantly higher among those who had reported falls at the first survey than in those who had not (relative risk; men; 2.71, women 2.40, p less than 0.05). 4) Most falls occurred during the daytime in either sex, with approximately 90% of falls for men and 60% of falls for women occurring outdoors. The cause of falls was mainly extrinsic. Compared to men, falls of women had a greater tendency to lead to major injury.

Accidental Falls↗
PubMed1991

[Leukocyte removability of a newly developed filter, RC-100, in rapid transfusion].

Leukocyte-depleted blood products are currently a burning issue in transfusion medicine. As methods for depleting leukocytes, the bedside filters are shown to have a high removal rate and several kinds of them are in use. We investigated the leukocytes removal rate of a new filter RC-100 (Pall Co., Glen Cove, NY) under the condition of rapid rate of transfusion during operations. In flow rates of 30, 60, 100 ml.min-1, the removal rate of leukocytes for CRC were 99.9 +/- 0.06, 100.0 +/- 0.00 and 99.4 +/- 0.20% respectively, and for WB 100.0 +/- 0.00, 99.9 +/- 0.10 and 99.1 +/- 0.70%, respectively. The recovery rates of erythrocytes were not significantly decreased for CRC and for WB in all flow rates. These results suggest that RC-100 could be useful either for CRC and for WB even with the rapid flow rate under 100 ml.min-1.

Blood Transfusion↗
PubMed1991

Effect of chlorpromazine on the toxicity of doxorubicin in mice.

The effect of chlorpromazine (CPZ) on the toxicity of doxorubicin (DOX) were investigated in mice. CPZ significantly enhanced the acute toxicity and bone marrow toxicity induced by DOX. These results suggest the potentiation of DOX toxicity by CPZ is due to increase of sensitivity of mice to DOX.

Animals↗
PubMed1991

Influence of chlorpromazine on the toxicity of pirarubicin in mice.

The influence of chlorpromazine (CPZ) on the toxicity of pirarubicin (THP) was examined in mice. CPZ significantly enhanced the acute toxicity and bone marrow toxicity induced by THP. These results demonstrate that that in vivo combination of THP and CPZ at high doses will result in an increase of toxicity in mice.

Animals↗
PubMed1990

Cell-free stimulation of the insulin-sensitive cAMP phosphodiesterase by the joint actions of ATP and the soluble fraction from insulin-treated rat liver.

The insulin-sensitive cAMP phosphodiesterase (PDE) from rat adipocytes was stimulated 60-70% upon incubation with 2 mM ATP and the soluble fraction (Fraction S-1) from insulin-treated rat liver. The effect of ATP was partially mimicked by ATP-gamma-S or GTP, but not by AMP-PNP. The PDE-stimulating activity in Fraction S-1 was preserved in the presence of 50 mM sodium phenyl phosphate, 50 mM sodium fluoride, and 0.1 mM sodium vanadate. The PDE-stimulating activity was not inhibited with either 0.5 mM H-7 or 5 microM PKI-(5-24)-peptide, but was blocked with 1 mM Kemptide. The active component in Fraction S-1 may be a phosphorylated compound, which, in the presence of ATP, may mediate the hormonal action on PDE.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1990

Stimulation of the insulin-sensitive cAMP phosphodiesterase by an ATP-dependent soluble factor from insulin-treated rat adipocytes.

The insulin-sensitive cAMP phosphodiesterase (PDE) in the microsomal fraction (Fraction P-2) from basal (-insulin) rat adipocytes was stimulated upon incubation with 2 mM ATP plus the soluble fraction from insulin-treated adipocytes (Fraction S-2+). Fraction S-2+ was prepared in the presence of p-nitrophenylphosphate, sodium vanadate, and EGTA. The ATP-dependent stimulation of PDE was routinely 60-70%. The unknown factor in Fraction S-2 was water-soluble, heat-labile, excluded by Sephadex G-50, mostly retained by Sephadex G-100, and not inhibited with 1 microgram/ml heparin, 3 mM CaCl2, or 30 mM NaF. The soluble factor may be a mediator of insulin action on PDE, possibly a protein kinase.

3',5'-Cyclic-AMP Phosphodiesterases↗