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Biomedical subjects

M Shimoyama

Publications and source records attributed to M Shimoyama.

At least 217 records · Page 12Linked to original sources
PubMed1987

ADP-ribosylation of Ca2+-dependent ATPase in vitro suppresses the enzyme activity.

We investigated the effect on the Ca2+-dependent ATPase activity of ADP-ribosylation of the enzyme from the rabbit skeletal muscle sarcoplasmic reticulum. A reconstituted ADP-ribosylation system of Ca2+-dependent ATPase in which the enzyme and ADP-ribosyltransferase, both were partially purified from the vesicles, and poly L-lysine were contained, was preincubated with 1 mM NAD, and the Ca2+-dependent ATPase activity was assayed. The NAD-dependent suppression of the enzyme activity depended on both the concentration of NAD and preincubation-time for the ADP-ribosylation, and was reversed by adding 20 mM arginine during the preincubation. These results taken together with the findings that Ca2+-dependent ATPase is a major acceptor protein for the modification in rabbit skeletal muscle sarcoplasmic reticulum [Hara et al. (1987) Biochem. Biophys. Res. Commun. 144; 856-862] suggest that Ca2+-transport in the sarcoplasmic reticulum may be regulated through changes in the rate of ADP-ribosylation of Ca2+-dependent ATPase.

Adenosine Diphosphate Ribose↗
PubMed1987

Mono(ADP-ribosyl)ation of Ca2+-dependent ATPase in rabbit skeletal muscle sarcoplasmic reticulum and the effect of poly L-lysine.

We investigated the endogenous mono(ADP-ribosyl)ation of the sarcoplasmic reticulum from rabbit skeletal muscle. The autoradiogram obtained after sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the [adenylate-32P]NAD-treated sarcoplasmic reticulum vesicles revealed a major band corresponding to the MW 105 K Ca2+-dependent ATPase and other bands corresponding to proteins of MW 153, 60 and 38 K and those of 125 to 135 K range. The addition of poly L-lysine during the incubation led to an enhancement of the modification. Poly L-lysine is proving to be a pertinent tool for identifying acceptor proteins.

Adenosine Diphosphate Ribose↗
PubMed1987

Potential limitation of growth-inhibitory action of recombinant human tumor necrosis factor (PAC-4D) due to easy induction of resistance: evidence in vitro.

The growth-inhibitory activity of recombinant human tumor necrosis factor (rH-TNF: PAC-4D) against 32 human cultured cell lines derived from leukemias and lymphomas (7 T cell, 11 B cell, 5 non-T,non-B cell and 9 myeloid cell lines) was measured quantitatively by in vitro regrowth assay. The growth of two non-T,non-B-cell lines (Reh, P30/OHK) and six myeloid cell lines (ML-1, U937, THP-1-0, P31/FUJ, P39/TSU, HEL) was found to be significantly inhibited by a 72 hr treatment with PAC-4D. Although the levels of sensitivity of these cell lines to PAC-4D were different, it was common to all these cell lines that increasing the dose of PAC-4D did not augment the growth-inhibitory action above a certain level. Neither dose-dependent nor time-dependent growth-inhibitory action was observed, namely, exposure to 100 U/ml of PAC-4D for 48 hr was sufficient to exhibit maximum growth-inhibitory action. Furthermore U937 cells were found to become completely resistant to PAC-4D during a continuous 12-day exposure to it. This resistance, however, was lost on culture of the cells with PAC-4D-free growth medium for 15 days. These results suggested that some non-T,non-B acute lymphoblastic leukemias and acute myelogenous leukemias might show an initial response to PAC-4D therapy, but prolonged administration might induce resistance to PAC-4D rather than increase the anti-tumor effect.

Drug Resistance↗
PubMed1987

Chromosome aberrations and clinical features of adult T cell leukemia-lymphoma not associated with human T cell leukemia virus type I.

Chromosome aberrations and clinical features of three patients with adult T cell leukemia-lymphoma (ATL) not associated with human T cell leukemia virus type I (HTLV-I) are described. From their clinical features, two patients were diagnosed as acute type and one patient was diagnosed as chronic type, which later converted to acute crisis. Clonal and many chromosomal abnormalities were observed before therapy in the two acute type cases and at relapse in the chronic type case. Karyotype aberrations, including trisomy 3, trisomy 7, trisomy 21, del(6)(q21), del(10)(p13), 14q11 translocation, and loss of X chromosome, all of which are frequently found in HTLV-I associated ATL, were also seen in these cases of HTLV-I-negative ATL.

Acute Disease↗
PubMed1987

A unique T-cell line derived from an HTLV-1-negative adult T-cell leukemia patient.

A unique T-cell line, designated ATL-5T, was established from lymphoma cells in pericardial effusion of an adult T-cell leukemia (ATL) patient not carrying HTLV-1 provirus. The cell line is OKT4 and/or Leu3a+ and OKT8 and/or Leu2a+, but interleukin 2 receptor (IL2R)- and HTLV-1 provirus genome negative, and has cytogenetically abnormal karyotypes. The cell line contains rearranged T-cell receptor beta-chain gene, which was identical in rearrangement pattern to the T-cell receptor beta-chain gene in primary cells. These results suggest that factors other than HTLV-1 may sometimes be associated with HTLV-1-negative ATL. The ATL-5T cell line we describe here is unique, and should contribute to further elucidation of the mechanisms involved in the pathogenesis of HTLV-1-negative ATL and HTLV-1-positive ATL.

DNA, Viral↗
PubMed1987

Prevalence of antibodies to human T-cell leukemia/lymphoma virus type I and human immunodeficiency virus in Japanese immigrant colonies in Bolivia and Bolivian natives.

This study was performed to estimate human T-cell leukemia-lymphoma virus type-I (HTLV-I) infection and human immunodeficiency virus (HIV) infection in Japanese immigrant colonies in Bolivia, where no seroepidemiological study of HTLV-I or HIV has ever been reported, among 647 healthy adults and children of Japanese descent and Bolivian natives living in the same colonies. The overall prevalence of HTLV-I antibody was 12.6% (59/469) among Japanese immigrant populations, but increased with age, being 16.2% (49/303) among adults and 6.0% (10/166) among children; no significant difference in relation to sex was noted. The first generation immigrants (issei) from Kyushu, the large southwestern island of Japan where adult T-cell leukemia (ATL) is endemic, had 19.0% (49/258) HTLV-I seroprevalence, while issei from outside Kyushu had none (0/39). Among Bolivian members of the community, consisting mostly of Indians and persons of Spanish descent, the HTLV-I seroprevalence was 4.3% (7/164) overall, 2.4% (1/42) among adults and 4.9% (6/122) among children. No antibody to HIV was detected among Japanese or Bolivian populations. The results of this study show that: (1) there is a considerable number of HTLV-I carriers among Japanese immigrant populations in Bolivia, especially among immigrants from Kyushu, (2) there exist some HTLV-I carriers among Bolivian natives, raising the possibility of HTLV-I transmission by co-habitation with Japanese immigrants, (3) HIV is far from endemic in this district of Bolivia, at present.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Revascularization surgery for 28 patients with moyamoya disease--operative methods, outcome and postoperative angiography.

51 times (sides) of reconstructive surgery using 28 patients with moyamoya diseases were evaluated concerning operative methods, outcome and postoperative angiographic findings. Twenty patients (72%) showed excellent results, 7 patients (25%) good and 1 patient (3%) poor. Development of collaterals shown on postoperative angiograms was excellent on 20 sides, good on 9 sides, and fair on 8. Abundant neovascularization was most commonly noted on angiogram in superficial temporal artery-middle cerebral artery bypass with encephalo-myo-synangiosis. Encephalo-myo-arterio-synangiosis, devised by the authors, or encephalo-myo-synangiosis alone also produced preferable development of collaterals shown on angiogram. Superficial temporal artery-middle cerebral artery bypass alone was insufficient for development of neovascularization.

Adolescent↗
PubMed1986

Immunoblastic lymphadenopathy, angioimmunoblastic lymphadenopathy, and IBL-like T-cell lymphoma. A spectrum of T-cell neoplasia.

Thirty cases of immunologically determined and histologically diagnosed immunoblastic lymphadenopathy (IBL), angioimmunoblastic lymphadenopathy (AILD), and IBL-like T-cell lymphoma were clinicopathologically reviewed. Clinical manifestations and laboratory findings did not reveal significant differences in these three groups. IBL, AILD, and IBL-like T-cell lymphoma showed a spectrum of histologic changes, in which proliferation of pale cells was a critical diagnostic point for the histologic malignancy. Immunostaining for their subsets revealed that 3 of 21 cases showed T4+ phenotype and the remaining 19 cases showed T8+ phenotype. Three of seven immunohistochemically determined T8+ cases simultaneously expressed Leu7+ phenotype. The latter cells were consistent with large granular lymphocytes in one case, but no clinicopathological differences from the other T8+ cases were present. IBL and AILD were considered to be T-cell malignancies, which show a spectrum of histologic features from T-cell dysplasia to peripheral T-cell lymphoma (IBL-like T-cell lymphoma). Despite intensive chemotherapy, prognosis was poor in T8+ cases of which half of the patients died within 1 year. T4+ cases showed better prognosis, but a higher incidence of synchronous second primary cancers was recognized.

Adult↗
PubMed1986

Adult T-cell leukemia/lymphoma not associated with human T-cell leukemia virus type I.

We describe five patients with adult T-cell leukemia/lymphoma (ATL) with neither integration of human T-cell leukemia virus type I (HTLV-I) into their leukemia cells nor anti-HTLV-I antibody in their sera. These findings indicate that HTLV-I may not have been involved in leukemogenesis in these patients. The clinicohematological, cytopathological, and immunological features of HTLV-I-negative ATL were exactly the same as those of HTLV-I-associated ATL. Leukemia cells with pleomorphic nuclei, generalized lymphadenopathy, hepatosplenomegaly, skin lesions, hypercalcemia, and elevated lactate dehydrogenase levels, all of which are characteristic features of typical ATL, were also seen in these patients with HTLV-I-negative ATL. Leukemia cells expressed T3, T4, and pan-T-cell antigens in three cases, and T3 and pan-T-cell antigens in two. All five patients had lived in ATL-nonendemic areas. The finding of HTLV-I-negative ATL suggests that factor(s) other than HTLV-I infection may be involved in ATL leukemogenesis.

Adult↗
PubMed1986

Effects of neurotransmitters or drugs on the in vivo release of dopamine and its metabolites.

The effects of neurotransmitters or drugs on the release of endogenous dopamine (DA) and extracellular levels of its metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), were examined in vivo by intracerebral dialysis. A dialysis tube was implanted stereotaxically through bilateral caudate nuclei of rats and perfused with the Ringer solution. Amounts of DA, DOPAC and HVA in the perfusates were measured by high performance liquid chromatography (HPLC) with electrochemical detection. The basal level of DA was 2.76 +/- 0.64 pg/min, whereas the levels of DOPAC and HVA were 218.7 +/- 20.7 and 142.4 +/- 10.6 pg/min, respectively. Apomorphine (4 mg/kg, i.v.) reduced the efflux of DA and its metabolites. Haloperidol (0.4 mg/kg, i.v.) did not change DA release and produced only a minor increase of its metabolites. This increase of metabolites was inhibited by pargyline. Met-enkephalin (10(-4) M), substance P (10(-4) M) and acetylcholine chloride (10(-4) M) added to the perfusing medium increased the release of DA. Met-enkephalin also increased the release of DOPAC. gamma-Amino-n-butyric acid (GABA, 10(-4) M) reduced the release of DOPAC and HVA when added to the perfusing medium. Thyrotropin releasing hormone (TRH, 5 mg/kg, i.v.) increased the release of HVA. These findings indicated that different mechanisms mediated effects of neurotransmitters or drugs on the release and metabolism of DA in the rat striatum.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1986

Karyotype aberrations and surface marker analyses of the tumor cells of Hodgkin's disease: a case report and review of literature.

Fresh tumor cells from pleural effusion of a patient with Hodgkin's disease were analyzed cytogenetically, immunologically and enzymocytochemically. They were characterized by the presence of alpha-naphthyl butyrate esterase activity, Fc gamma-receptor, HLA-DR antigen and No. 9 antigen which has been shown to be present in Hodgkin's cells and granulocytes, and the absence of definite T-, B- and myeloid cell markers. The karyotype analysis of these tumor cells revealed chromosome instability, but the clonality was confirmed by the many common abnormalities such as -4, -6, -10, -12, -13, -14, +21, del(X) (q22,q26), del(7) (q32q36), and +der(19)t(19;?). In addition, there were more duplicated tetraploid clones than near-diploid clones. The karyotype of the near-diploid clone was interpreted as: 48, X, del(X) (q22q26), -4, -6, -10, -12, -13, -14, +20, +21, +der(4)t(4;?) (p16;?), del(7) (q32q36), +der(19)t(19;?) (p13;?), +mar1, +mar2, +mar3. The karyotype abnormalities characteristic of lymphomas or leukemias were not found. These results indicate that the tumor cells are not of lymphoid or myeloid lineage. Further studies are needed to determine the cellular origin of the tumor cells of Hodgkin's disease.

Adult↗
PubMed1986

Antibodies to human immuno-deficiency virus and human T-cell leukemia virus type I in Japanese patients with hematologic malignancies.

One thousand six hundred and seventy-four blood samples drawn between January 1980 and April 1986 from 1454 Japanese, including 251 leukemia, 409 lymphoma, 76 adult T-cell leukemia and 25 benign lymphadenitis patients, were tested for antibodies to HIV and HTLV-I. No patient with lymphadenitis or lymphoma associated with HIV infection was found. In 87 patients with acute and chronic leukemias who had received multiple transfusions, 8 were positive for anti-HTLV-I antibody after blood transfusions amounting to 115 units, on average, while no patient was positive for anti-HIV antibody. Overall, no sample was positive for anti-HIV antibody, whereas 153 (10.5%) were positive for anti-HTLV-I antibody. These results indicate that the transmission of HIV by blood transfusions is far less prevalent than that of HTLV-I in Tokyo at present.

Acquired Immunodeficiency Syndrome↗