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Biomedical subjects

T Shibuya

Publications and source records attributed to T Shibuya.

At least 325 records · Page 18Linked to original sources
PubMed1987

Selective effects of ethanol on opiate receptor subtypes in brain.

Large concentrations of ethanol in vitro decreased ligand binding to mu and delta opiate receptors in the frontal cortex of the C57BL mouse, but did not alter binding to kappa opiate receptors. Mu and delta receptors were equally sensitive to the inhibitory effect of ethanol. Since the effects of ethanol were significant only in large concentrations, ethanol may alter opiate binding through its membrane lipid-perturbing actions, and the selectivity of the effects of ethanol may reflect differences in the microenvironments of the opiate receptor subtypes in membranes. After chronic ingestion of ethanol by mice, in vivo, there was a selective decrease in the number of mu receptors in the frontal cortex. This change may result from indirect effects of ethanol on the opiate receptor and may contribute to specific central effects of ethanol.

Animals↗
PubMed1987

Treatment of four patients with myelodysplastic syndrome with a small dose of aclacinomycin-A.

The effect of a small dose of aclacinomycin-A (ACR) was examined in two patients with refractory anemia (RA) and two with refractory anemia with excess of blasts in transformation (RAEB-t). ACR (7 or 14 mg/m2) was given for 10 days in a 2-h per day drip infusion. Clinical symptoms and laboratory data improved in 3 of these 4 patients. In a patient with RA, marked increase in reticulocytes and elevation of the hemoglobin level from 6 to 9 g/dl was observed after two courses of ACR therapy. In two with RAEB-t, Auer's rod bearing cells disappeared in the bone marrow and megaloblastic change of the erythroblasts was diminished in one patient. Hemoglobin levels rose from 4.7 to 10 g/dl in one, and platelets and WBC increased in another. No effect was seen in a patient with RA. The cytoreductive effect of ACR was minor compared to the therapy with small dose of cytosine arabinoside (Ara-C). Therefore, ACR warrants further consideration for the treatment of patients with MDS.

Aclarubicin↗
PubMed1987

Effects of glycyrrhizin and glycyrrhetinic acid on growth and melanogenesis in cultured B16 melanoma cells.

The effects of glycyrrhizin (GL) and its aglycone, glycyrrhetinic acid (GA), on the growth and differentiation of mouse melanoma (B16) cells in culture were studied. GA inhibits the growth of B16 melanoma cells, causes morphological alterations and stimulates melanogenesis. GL also resulted in the same changes but only when the concentration was about 20 times more than that needed for GA. When GA was removed after 84 h of treatment, the growth rate recovered slightly, but the doubling time was about twice that of the control. Cytofluorometric analysis showed that the growth inhibition of GA is the result of inhibition of the transfer from G1 to S phase.

Animals↗
PubMed1987

Differential effect of ethosuximide and of electrical stimulation on inhibitory and excitatory mechanisms.

Much longer trains of conditioning stimuli are required to elicit inhibition descending from the reticular formation than to elicit segmental inhibition in the trigeminal nucleus. In contrast, a single conditioning stimulus is the most effective in eliciting descending facilitation, while the test stimulus alone is most effective in eliciting segmental excitation. Ethosuximide (ESM) selectively depresses descending inhibition and to a lesser extent segmental inhibition. Thus, ESM only depresses pathways requiring repetitive stimulation, such as inhibitory pathways in the reticular formation. This action would account for ESM's specificity for absence seizures, which are probably due to paroxysmal activity in inhibitory pathways.

Animals↗
PubMed1987

Study on nonspecific immunity in pregnant women: increased chemiluminescence response of peripheral blood phagocytes.

The total number of circulating leucocytes in the peripheral blood of pregnant women progressively increased with advance in gestation because of neutrophilia. When the phagocytic activity, representing nonspecific immunity, was estimated by a luminol-dependent chemiluminescence (CL) response during phagocytosing opsonized zymosan, we observed that the CL response of whole blood and Ficoll-Paque separated polymorphonuclear leucocytes (PMNL) significantly increased throughout the pregnancy (P less than 0.01). The CL responses of mononuclear leucocytes (MN) and monocytes also increased and reached peak levels in the third trimester (P less than 0.05). These findings suggest that the phagocytic activity in pregnant women increases, not only with regard to the number of phagocytes but also with regard to individual cell function, from a relatively early stage of the pregnancy, and that this increased nonspecific immunity may compensate in part for a weakened specific immunity of the maternal host. Attention should be directed to effects of human chorionic gonadotropin (hCG) relative to the increased CL response during pregnancy.

Adult↗
PubMed1987

Aplastic anemia associated with type A viral hepatitis--possible role of T-lymphocytes.

Posthepatitic aplastic anemia (PHAA) is rather uncommon. Most reported cases have developed after non-A, non-B or B type hepatitis. The only case of PHAA occurring after hepatitis A reported so far, was described by Smith et al., who diagnosed it by the long-term elevation of IgG-class antibody in response to hepatitis A virus. Recently, the detection of IgM-class antibody specific against hepatitis A virus (IgM anti-HAV) has been commonly employed for precise diagnosis of hepatitis A. The case reported here is the first case of PHAA occurring after hepatitis A to be diagnosed by radioimmunoassay of IgM anti-HAV. Furthermore, evidence is presented suggesting that the PHAA may have been an immune-related response. Addition of the patient's peripheral T-lymphocytes to cultures of her own bone marrow cells resulted in a reduction in the number of colony-forming units in culture (CFU-C).

Adult↗
PubMed1987

Human bladder carcinoma cell line HTB9, which secretes a factor to stimulate clonogenic leukemic blast growth, expresses the granulocyte-macrophage colony-stimulating factor gene.

Media conditioned by the human bladder carcinoma cell line HTB9 contained high leukemic blast growth factor activity and also showed granulocyte-macrophage colony-stimulating factor (GM-CSF) activity. Northern blotting analysis of total RNA from HTB9 cells using GM-CSF cDNA as a probe demonstrated abundant expression of the GM-CSF gene. Thus, this cell line secretes GM-CSF, and this factor contributes to the proliferation of clonogenic leukemic blast cells.

Carcinoma↗
PubMed1987

[Malignant hemangiopericytoma of the right ventricular outflow tract and the pulmonary artery: a case report].

A case of malignant hemangiopericytoma of the right ventricular outflow tract and the pulmonary artery associated with formation of a pseudoaneurysm in the latter is presented. This 33 year-old man had a four month history of illness. From the surgical point of view, all non-invasive modalities including phonocardiography, M-mode and two-dimensional echocardiography, radionuclide angiocardiography and contrast computed tomography underestimated the extent of the tumor as compared with the selective cineangiographic estimation. Therefore, it was suggested that in some situations where surgery is contemplated, a combination of non-invasive methods and cineangiography is essential to obtain sufficient diagnostic information, although the introduction of catheters into the right-sided cardiac chambers containing a mass might be hazardous because of potentiality dislodging portions of a tumor or adherent thrombus. Concerning pericardial abnormalities, contrast computed tomography was the most sensitive and specific method among the diagnostic techniques used in this case.

Adult↗
PubMed1987

[A case of Ewing's sarcoma treated successfully by combination chemotherapy consisting of high-dose methotrexate, aclacinomycin-A and vindesine].

A 22-year-old man was admitted to Kyushu University Hospital because of high fever, and pain in the right foot and back. An X-ray examination revealed an osteolytic lesion on the 5th metatarsal bone of the right foot. Paraplegia and disturbance of bladder function occurred and compression of the spinal cord between T3 and L5 was found by myelography. An extradural tumor was removed by emergent laminectomy, and a histological examination of the tumor showed aggregations of small round cells, which suggested Ewing's sarcoma. Although T-9 protocol was started with initial effect, the tumor recurred during the therapy. The patient was then treated with HD-MTX, ACR and VDS, which induced a clinical improvement for 4 months without maintenance therapy. This result showed that HD-MTX, ACR and VDS warrant further consideration for the treatment of refractory Ewing's sarcoma.

Aclarubicin↗
PubMed1987

IgG and IgE antibodies to Chironomidae in asthmatic patients.

IgG antibodies to Chironomidae and its correlations to radioallergosorbent and skin reactions were examined with the aim of clarifying the relationship between asthma and Chironomidae. The level of specific IgG antibody in asthmatic patients (0.698 +/- 0.034, n = 104) was significantly greater than that in normal subjects (0.367 +/- 0.032, n = 52) (P less than 0.01). The specific IgG level was not correlated to skin reaction, nor to IgE RAST scores. Specific IgG1 and IgG4 levels in asthmatic patients were significantly greater than in control subjects (n = 14) (P less than 0.01).

Animals↗