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H Shibata

Publications and source records attributed to H Shibata.

At least 19 recordsLinked to original sources
PubMed1992

Stimulation of glucose transport by guanine nucleotides in permeabilized rat adipocytes.

Effects of guanine nucleotides on glucose transport were studied in permeabilized rat epididymal fat cells. GTP gamma S and Gpp(NH)p, but not App(NH)p, stimulated 3-O-methylglucose transport. Effect of GTP gamma S was dose-dependent, being detectable at 0.1 mM, and 1.0 mM GTP gamma S stimulated glucose transport to the same extent as insulin. GTP gamma S (0.3 mM) enhanced insulin-stimulated glucose transport while 1 mM GTP gamma S did not affect insulin-mediated transport. GDP beta S had no effect on glucose transport by itself but rather enhanced insulin action. NaF, which is known to activate trimeric G proteins, increased glucose transport to the same extent as insulin. Likewise, mastoparan augmented glucose transport. These results indicate that a certain type of trimeric G protein(s) is involved in the regulation of glucose transport.

3-O-Methylglucose↗
PubMed1992

Topographic organization of subcortical projections to the anterior thalamic nuclei in the rat.

Subcortical projections to the anterior thalamic nuclei were studied in the rat, with special reference to projections from the mammillary nuclei, by retrograde and anterograde transport of wheat germ agglutinin conjugated to horseradish peroxidase. The medial mammillary nucleus (MM) projects predominantly ipsilaterally to the entire anterior thalamic nuclei, whereas the lateral mammillary nucleus projects bilaterally to the anterodorsal nucleus (AD) of the anterior thalamic nuclei. A topographic relationship was recognized between the MM and the anterior thalamic nuclei. The dorsal region of the pars mediana of the MM projects to the interanteromedial nucleus (IAM), whereas the ventral region projects to the rostral part of the anteromedial nucleus (AM). The dorsal and the ventral regions of the pars medialis project to the dorsomedial part of the AM at its caudal and rostral levels, respectively. The dorsomedial region of the pars lateralis projects to the ventral AM. The ventrolateral region of the pars lateralis projects to the ventral part of the anteroventral nucleus (AV) in such a manner that rostral cells project rostrally and caudal cells project caudally. The pars basalis projects predominantly ipsilaterally to the dorsolateral AV and bilaterally to the AD. The rostrolateral region of the pars posterior projects to the lateral AV, whereas the medial and the caudal regions of the pars posterior project to the dorsomedial AV. The rostrodorsal part of the nucleus reticularis thalami was found to project to the anterior thalamic nuclei; cells located rostrally in this part project to the IAM and AM, whereas cells located caudodorsally project to the AV and AD. The laterodorsal tegmental nucleus projects predominantly ipsilaterally to the AV, especially to its dorsolateral part. The present study demonstrates that subdivisions of the subcortical structures are connected to the subnuclei of the anterior thalamic nuclei, with a clear-cut topography arranged in the dorsoventral and the rostrocaudal dimensions.

Animals↗
PubMed1992

Inhibitory effect of noradrenaline on acute liver injury induced by carbon tetrachloride in the rat.

The effect of exogenous noradrenaline (NA) on acute liver injury was investigated in rats receiving a single dose of carbon tetrachloride (CCl4). Animals were divided into the following groups: (I) no treatment, used for plasma catecholamine assay; (II) received CCl4 only; (III) treated with CCl4 plus noradrenaline (NA). Plasma levels of catecholamine (CA) were elevated in both groups II and III, particularly in NA: average value at 33 h after the exposure of CCl4 increased to 290-fold of the control in group II and to 513-fold in group III. Subsequently, the levels of NA decreased with time, and were comparatively well-preserved in the rats of group III. Hepatic changes observed in the animals of group II were as follows: destruction with reduced number in rough endoplasmic reticulum; destruction and disappearance of cristae in mitochondria, and numerous fat droplets (shown by electron microscopy); histologically observed marked centrilobular necrosis with steatosis followed by progression with time; and microangiographically demonstrated deranged intrahepatic microvasculature. By contrast, these changes were successfully prevented by NA treatment (group III). Furthermore, histologically observed centrilobular change was restored with time. It was concluded that, in a deranged state, NA takes a form quite dissimilar to ordinary state: Na exerts for hapatoprotective and is highly involved in liver injury.

Animals↗
PubMed1992

Menotropin stimulation after prolonged gonadotropin releasing hormone agonist pretreatment for in vitro fertilization in patients with endometriosis.

Two protocols were scheduled for in vitro fertilization and embryo transfer (IVF-ET) in patients with various stages of endometriosis who were resistant to conventional therapies. In the ultralong protocol (21 patients), gonadotropin releasing hormone agonist (Gn-RHa) was administered for at least 60 days prior to ovarian stimulation along with menotropin until human chorionic gonadotropin was injected. In the long protocol (11 patients), Gn-RHa was started at the midluteal phase and exogenous gonadotropin was commenced between the third and the seventh day of the menstrual cycle after pituitary suppression. The estradiol response and the number of retrieved oocytes, fertilized oocytes, cleaved oocytes, and transferred embryos were similar in both groups but the clinical pregnancy rate per transfer was superior in the ultralong protocol (67 vs 27%). The miscarriage rate was 14% (2/14) in the ultralong protocol. Prolonged Gn-RHa suppression of ovarian function before superovulation may overcome some causes of infertility in patients with endometriosis.

Adult↗
PubMed1992

Case report: hypertension in Cushing's syndrome.

Pathogenesis of hypertension in Cushing's syndrome has remained controversial. A 56-year-old Japanese man with Cushing's syndrome due to adrenal carcinoma has been followed up for more than 6 years. During the followup period, left adrenalectomy and hemihepatectomy due to metastatic lesion were performed. Blood pressure, serum cortisol, and urinary excretion of 17-OHCS, as well as other routine biochemicals, have been measured periodically. These data revealed that there is a marked correlation between the levels of blood pressure and serum cortisol or urinary excretion of 17-OHCS. This finding suggests that cortisol production by tumor is a determinant factor in hypertension in Cushing's syndrome.

Adrenal Gland Neoplasms↗
PubMed1992

Involvement of calcium in germination of coat-modified spores of Bacillus cereus T.

The effect of calcium on germination of coat-modified Bacillus cereus T spores was investigated. Coat-modified spores produced either by chemical extraction (SDS-DTT-treated spores) or by mutagenesis (10LD mutant spores) were unable to germinate in response to inosine. While SDS-DTT-treated spores could germinate slowly in the presence of L-alanine, 10LD mutant spores could not germinate at all. The lost or reduced germinability of coat-modified spores was restored when exogenous Ca2+ was supplemented to the germination media. The calcium requirement of coat-modified spores for germination was fairly specific. The simultaneous presence of germinant with Ca2+ was also required for germination of coat-modified spores. The optimal recovery of germinability was observed in the presence of 1.0 mM of calcium acetate. The calcium requirement itself was remarkably diminished under the condition in which L-alanine and a certain purine nucleoside analog, adenosine or inosine, coexisted. The lost or diminished germinability observed in SDS-DTT-treated spores or 10LD mutant spores may be attributed to the loss of calcium associated with the spore integuments.

Alanine↗
PubMed1992

Seroepidemiology status of Nepalese against hemolytic streptococcal infection in Katmandu.

Immune status of apparently healthy Nepalese against hemolytic streptococci was studied by measuring antibodies to various streptococcal antigens such as streptolysin-O (SO), streptokinase (SK), deoxyribonuclease-B (DN-B) and streptococcal polysaccharide (SP). The normal range of anti-streptolysin-O (ASO), anti-streptokinase (ASK), anti-deoxyribonuclease-B (ADN-B) and anti-Streptococcus polysaccharide (ASP) was 60-480 (T.U.), 40-1024 (titer), 60-1280 (titer) and less than 2-128 (Unit), respectively. No difference was observed between the two sexes. ASO and ADN-B were measured by the neutralization method. Passive hemagglutination (PHA) was used to measure ASK and ASP. These values were 2-3 fold higher than those obtained on the Japanese subjects.

Adolescent↗
PubMed1992

Human melanoma cells derived from lymphatic metastases use integrin alpha v beta 3 to adhere to lymph node vitronectin.

Human melanoma is a highly metastatic cancer and the regional lymph nodes are generally the first site of metastasis. Adhesion to cryostat sections of human lymph nodes was therefore studied using two human melanoma models established from lymph node metastases, namely, MeWo cell lines of diverse metastatic potentials and a highly metastatic cell line of recent origin designated MIM/8. We found a good correlation between the metastatic potentials of the melanoma cells as measured in nude mice and their ability to adhere to cryostat sections of human lymph nodes. When adhesion to immobilized extracellular matrix proteins was measured, a significant increase in adhesion, which correlated with increased metastasis, was seen mainly on vitronectin and to a lesser extent on fibronectin. The adhesion to vitronectin and to the frozen sections were specifically blocked by an RGD-containing peptide, mAb 661 to vitronectin and mAb LM609 to integrin alpha v beta 3. FACS analysis revealed a significant and specific increase in cell surface expression of alpha v beta 3 on the metastatic cells as compared to the parent line. Together these results suggest that the adhesion of melanoma cells to lymph node vitronectin via the alpha v beta 3 receptor plays a role in the process of lymphatic dissemination.

Animals↗
PubMed1992

Nutrition for the Japanese elderly.

The present paper examines the relationship of nutritional status to further life expectancy and health status in the Japanese elderly based on 3 epidemiological studies. 1. Nutrient intakes in 94 Japanese centenarians investigated between 1972 and 1973 showed a higher proportion of animal protein to total proteins than in contemporary average Japanese. 2. High intakes of milk and fats and oils had favorable effects on 10-year (1976-1986) survivorship in 422 urban residents aged 69-71. The survivors revealed a longitudinal increase in intakes of animal foods such as eggs, milk, fish and meat over the 10 years. 3. Nutrient intakes were compared, based on 24-hour dietary records, between a sample from Okinawa Prefecture where life expectancies at birth and 65 were the longest in Japan, and a sample from Akita Prefecture where the life expectancies were much shorter. Intakes of Ca, Fe, vitamins A, B1, B2, C, and the proportion of energy from proteins and fats were significantly higher in the former than in the latter. Intakes of carbohydrates and NaCl were lower.

Aged↗
PubMed1992

Effect of soft x-ray irradiation on immunological functions in mice.

Effect of soft x-ray irradiation on immunological functions in mice was investigated. Soft x-ray irradiation with 100R or more induced a significant reduction in the number of plaque-forming cells (PFC). The reduction in the number of PFC depended on the irradiation doses. Irradiation with 600R or more showed a significant reduction in the delayed reaction of footpad swelling. However, soft x-ray irradiation with doses ranging from 100R to 1000R did not exert significant influence on the K values of carbon clearance test. Irradiation with 100R or more of soft x-ray showed a remarkable reduction of response to concanavalinA (ConA) or lipopolysaccharide (LPS) in spleen cells, and the response to ConA was lower than that to LPS. These results suggest that in the soft x-ray-irradiated mice, antibody-producing ability, delayed type hypersensitivity reaction and mitogenic activity are sensitive to soft x-ray irradiation and furthermore, T cell is more sensitive than B cell, but phagocytic activity of reticulo-endothelial system (RES) is resistant to soft x-ray irradiation.

Animals↗
PubMed1992

Adult T-cell leukemia with a solitary lung mass.

A 49-year-old woman was admitted to the hospital with supraclavicular lymph node swelling. On a chest x-ray film, a 4 x 4-cm nodular shadow was observed in the right middle lung field. The white blood cell count was 10,100/cu mm, showing 44 percent abnormal lymphocytes with lobulated nuclei. Since HTLV-I antibodies were markedly positive, she was diagnosed as having ATL. Transbronchial tumor biopsy revealed accumulation of ATL cells. Our patient is the first case with only a large nodular accumulation of ATL cells without diffuse infiltration of the cells in the lung.

Female↗
PubMed1992

Gonadotropin induces expression of c-fos and c-jun genes in rat ovaries.

It has been shown that the expression of protooncogenes, c-fos and c-jun, induced by growth factors and hormones plays important roles in cellular proliferation, tissue differentiation and transcription of certain genes. Since gonadotropin stimulates ovarian steroidogenesis and cellular proliferation, we investigated whether gonadotropin affects the expression of c-fos and c-jun genes in rat ovaries. The expression of mRNA coding side chain cleavage enzyme (P450scc), the rate limiting enzyme in ovarian steroidogenesis was also studied. The effect of gonadotropin was examined in female rats whose gonadotrophs were medically ablated by GnRH agonist (TAP-144-SR). After intravenous administration of pregnant mare's serum gonadotropin (PMSG:30 IU/rat), their ovaries were dissected out at various time intervals and total RNA was extracted. Changes in the levels of c-fos, c-jun and P450scc mRNAs were determined by Northern blot analysis. The levels of c-fos and c-jun mRNAs increased rapidly and transiently with the peak levels at 15 min after PMSG administration. The levels of both mRNAs were decreased by 30 to 60 min. On the other hand, the levels of P450scc mRNA started to increase 60 min after PMSG. These results indicate that gonadotropin-induced increase in the expression of c-fos and c-jun genes may play important roles in mediating the action of gonadotropin on the ovaries.

Actins↗
PubMed1992

[A study on 24-hour ambulatory blood pressure in normotensive elderly, living in a local home for the aged].

Ambulatory blood pressure (BP) was non-invasively monitored in 124 normotensive elderly, living in an old people's home at the annual health examination. Cases were divided into 41 cases < 75 years (group A, mean age 70.6) and 83 cases > or = 75 years (group B, 82.7) for analysis of the office BP and 24-hour BP. Whole-day systolic BP in group B was significantly higher than those in the group A (p < 0.02) although no significant differences were observed in diastolic BP and pulse rate. Separated analysis of whole-day BP into daytime and nighttime revealed that the nighttime systolic BP in the group B was significantly higher than those in group A (132.2 +/- 17.4% vs. 123.8 +/- 18.6 mmHg, p < 0.02) whereas no significant difference was observed in day-time systolic BP between two groups (136.6 +/- 14.9 vs. 132.1 +/- 14.4 mmHg, n.s.). The day-night difference in systolic BP tended to be less in group B than in group A (4.5 +/- 11.6 vs. 8.2 +/- 12.2 mmHg, p < 0.10). The prevalence of non-dippers, who had a higher nighttime systolic BP than daytime systolic BP were 24.4% of the group A and 30.1% of the group B. It was concluded that systolic BP during the nighttime increased with the ageing process after age 60, although that during daytime did not change.

Aged↗
PubMed1992

Is necrosis induction therapy relevant to hepatocellular carcinoma? Prognostic evaluation viewed from necrosing feature in HCC occluding the main portal vein after treatment with DBcAMP and MMC.

Intraarterial infusion therapy combining dibutyryl adenosine 3',5'-monophosphate and mitomycin C was administered to 27 patients with hepatocellular carcinoma (HCC) occluding the main portal vein. Twelve patients (44%) survived more than 6 months, among them nine (75%) whose tumors were non-necrosing before treatment. When patients were compared for the presence or absence of necrosis in the tumor, those with necrosis responded poorly to treatment; only 3 of 11 (27%) survived more than 6 months. Although the combination therapy exerted a salutary effect on HCC occluding the main portal vein, the presence of necrosis in the tumor was an unfavorable sign for the prognosis, which casts doubt upon the use of the necrosis-inducing method for the treatment of HCC.

Adult↗
PubMed1992

Marked increase of CD57+CD16- cells in long-term survivors of graft-versus-host disease after allogeneic bone marrow transplantation.

We have evaluated long-term serial changes in the immunological state from soon after allogeneic bone marrow transplantation (BMT) In 44, mainly leukemia patients with respect to changes in lymphocyte surface markers. Absolute numbers of cluster designation (CD)2+, CD20+ and human lymphocyte antigen-DR+ (HLA-DR+) cells recovered to within their normal ranges three months, one year and two years, respectively, after BMT. The reversal of the CD4+: CD8+ ratio persisted for five years or more but returned to normal after six years. CD57+CD16- cells were markedly increased from three mo up to a maximum of five years after transplantation; they were increased between three and six months after transplantation irrespective of graft-versus-host disease (GVHD), but changes after one year or more differed among patients without GVHD, with acute GVHD, with acute and chronic GVHD or with chronic GVHD. Absolute numbers of CD57+CD16- cells tended gradually to return to normal after one year or more in the group without GVHD but only after six years in patients in the other three GVHD groups.

Adolescent↗
PubMed1992

[IgM HCV antibody in chronic hepatitis and liver cirrhosis].

To evaluate the role of IgM specific antibody in the diagnosis and monitoring of the patients with chronic hepatitis C, sera from 114 cases with chronic hepatitis C and liver cirrhosis were tested. IgM antibody to hepatitis C virus was detected in 40.0% of CAH, as compared with 21.4% of CIH, 17.4% of LC, 20.0% of LC with HCC. IgM antibody was also detectable in cases with high level of s-ALT. Patients with positive this antibody have high titer of IgG antibody to hepatitis C virus. In summary, testing for this antibody may be useful to evaluate the recurrence or disease activity and may also be helpful in IFN therapy.

Adult↗