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Biomedical subjects

S Yoshimoto

Publications and source records attributed to S Yoshimoto.

At least 91 records · Page 5Linked to original sources
PubMed1988

Serum and erythrocyte magnesium levels in junior high school students: relation to blood pressure and a family history of hypertension.

Serum and erythrocyte magnesium concentrations (S-Mg, E-Mg) were measured in 380 Japanese junior high school students, and the relationship to blood pressure and a family history of hypertension were studied. Systolic blood pressure was higher in the subjects with a positive family history of hypertension [FH(+)] than in those with a negative family history [FH(-)], whereas E-Mg was lower in the FH(+) group than in the FH(-) group with a significant different in boys. Furthermore, in the FH(+) group, systolic blood pressure was significantly higher in the subjects with lower S-Mg and E-Mg than in those with higher S-Mg and E-Mg. In the FH(-) group, however, no difference was observed in blood pressure levels between the two subgroups. These findings suggest that magnesium deficiency is partially responsible for a rise of blood pressure in the FH(+) children, and that a genetic predisposition of hypertension may be closely related to magnesium metabolism.

Adolescent↗
PubMed1987

Structural characterization of the isoenzymatic forms of human myeloperoxidase.

Myeloperoxidase from human neutrophils was isolated by ion-exchange and gel-filtration chromatography and shown by SDS-polyacrylamide gel electrophoresis to be comprised of alpha and beta subunits with apparent Mr values of 58,000 and 15,000, respectively. The apparent Mr of the native protein was 130,000-140,000, indicating that the holoenzyme has the quaternary structure alpha 2 beta 2. Automated Edman degradation of the separated alpha and beta subunits showed that the amino-terminal sequences were different from one another and demonstrated no sequence microheterogeneity. Comparison of these sequences with those in the National Biomedical Research Foundation data bank of protein sequences revealed that the subunits of human myeloperoxidase were not homologous to any known protein. Myeloperoxidase purified from HL-60 cells grown in culture demonstrated the same alpha 2 beta 2 subunit structure. Three isoenzymes of myeloperoxidase, prepared by gradient elution from a CM-Sepharose column, underwent quantitative analysis. No structural basis for the different elution pattern of the myeloperoxidase isoenzymes was discerned by amino-acid analysis, N-terminal sequence, polyacrylamide gel electrophoresis, or digestion with neuraminidase or enzymes known to cleave N-linked heterosaccharides. The structural basis for the myeloperoxidase isoenzymes of human neutrophils, each possessing equivalent activity, is not apparent from these studies.

Amino Acid Sequence↗
PubMed1987

Urinary trace amine excretion and platelet monoamine oxidase activity in schizophrenia.

The relationship between subtypes of schizophrenia classified by ICD-9 and 24-hour urinary beta-phenylethylamine (PEA) and phenylacetic acid (PAA) excretion has been studied. Schizophrenia was divided into two types: paranoid and nonparanoid. Increased urinary PEA excretion was found in paranoid schizophrenics, but urinary PAA excretion did not show any significant difference between schizophrenics and normal subjects. A relationship between platelet monoamine oxidase (MAO) activity and urinary PEA excretion was found. These findings offer some indication that PEA may play a role in the pathogenesis of schizophrenia.

Adult↗
PubMed1987

Mother-to-offspring transmission of human T cell leukemia virus type I in rabbits.

We studied the mode of natural transmission of human T-cell leukemia virus type I (HTLV-I) in rabbits. Four virus-infected rabbits (2 males and 2 females) were individually mated with 4 noninfected rabbits. Two virus-infected females mated with noninfected males gave birth to 7 offspring, and 2 noninfected females mated with infected males delivered 5 offspring. Four of the seven offspring born to the virus-infected mothers seroconverted for HTLV-I when aged 6 to 13 weeks with antibody titers of 1:40 to 1:160. None of the five offspring born to the noninfected mothers became seropositive during the observation period of 6 months, however. Peripheral lymphocytes were cultured with T cell growth factor, and HTLV-I-carrying lymphoid cell lines were established from the four seroconverted rabbits. All four cell lines were of T cells positive for Ia antigens. In addition, none of five newborn rabbits killed immediately after birth to a virus-infected rabbit was infected with HTLV-I. These findings provide an experimental support for the milkborne transmission of HTLV-I from mother to child in humans and indicate that the virus is tropic for T cells in rabbits as well.

Animals↗
PubMed1986

Serial transmission of human T-cell leukemia virus type I by blood transfusion in rabbits and its prevention by use of X-irradiated stored blood.

Human T-cell leukemia virus type I (HTLV-I) was serially transmitted for 5 passages from rabbit to rabbit by blood transfusion. The virus could be transmitted with 20 ml of whole blood or washed blood cell suspension (fresh or stored for 1-2 weeks at 4 degrees C) but not with cell-free plasma from seroconverted rabbits. Seroconversion occurred 2-4 weeks after blood transfusion and serum anti-HTLV-I titers ranged from 1:20 to 1:640 with the immunofluorescence assay. From transfusion recipients of the 1st to 4th passages, virus-producing cell lines were established by culturing lymphocytes in the presence of T-cell growth factor (TCGF). Three of the 4 cell lines became TCGF-independent after 2-12 months of continuous culture. Blood was transfused between rabbits of opposite sexes and the recipient origin of each cell line was determined by chromosome analysis. We also investigated the effect of X-irradiation (6,000 rad) on blood from seropositive rabbits. Seroconversion likewise occurred in rabbits transfused with blood that had been irradiated immediately before transfusion but not in rabbits transfused with blood that had been irradiated and stored for 1-2 weeks at 4 degrees C. Thus, our rabbit model shows that HTLV-I is serially transmissible by blood transfusion and that this can be prevented by irradiation of blood. The same procedure, therefore, may be useful for the prevention of transfusion-related transmission of HTLV-I in humans.

Animals↗
PubMed1986

Electron microscopic and immunohistochemical observations of differentiation of human myeloid leukemia line, PL-21.

A new human myeloid leukemia cell line, PL-21, consisting of promyelocytes, was microscopically and immunohistochemically studied for their maturation induced by 12-O-tetradecanoyl-phorbol-13-acetate (TPA) and retinoic acid (RA). More than 80% of PL-21 cells cultured for 4 days with 10 ng/ml of TPA became macrophage-like cells with functional and histochemical properties consistent with monocytes/macrophages. The cells adhered to the plastic flask, developed phagocytic activity and macrophage-specific intracytoplasmic alpha subunit of S-100 protein, and had reduced myeloid-specific cytochemical markers. In contrast, RA-treated PL-21 cells displayed mature neutrophil-like morphology after 7 days of exposure. Most of the cells had reduced nitro blue tetrazolium and acquired phagocytic activity with persistence of myeloid-specific cytochemical markers such as peroxidase, naphthol-AS-D chloroacetate esterase, and Sudan black B. These results indicate that the PL-21 cell line ca be induced to mature into two directions of macrophages and neutrophils by chemical inducers, and will provide a useful tool for studying the differentiation of leukemic cells and searching for other differentiation inducers.

Cell Differentiation↗
PubMed1986

[Association between uptake to lymphocytes from schizophrenic patients and therapeutic efficacy].

Using Le Fur's methods, 3H-spiperone binding was measured in lymphocytes from normal control persons. Although the haloperidol displaceable component of 3H-spiperone binding was present in intact lymphocytes, 3H-spiperone binding was not saturable over a wide range of ligand concentrations. It is suggested that this binding is associated with the degree of 3H-spiperone concentration transported into the lymphocytes. 3H-spiperone uptake to lymphocytes in schizophrenic patients (n = 10, including for chlorpromazine responders) and in normal control persons (n = 10) was measured. The 3H-spiperone uptake of schizophrenic patients was significantly higher than that of normal control persons. Especially in three out of the four chlorpromazine responders, 3H-spiperone uptake was much higher than in the rest of the schizophrenic patients. 3H-spiperone uptake of schizophrenic patients was independent of the daily medicational dosages. The 3H-spiperone uptake to the lymphocytes in schizophrenic patients seemed to be related to the therapeutic efficacy of the neuroleptics.

Adolescent↗
PubMed1986

Oral transmission of human T-cell leukemia virus type I in the rabbit.

Four female rabbits were given twice-weekly oral inoculation of 2-4 X 10(7) cells from a male rabbit lymphoid cell line persistently infected with human T-cell leukemia virus type I (HTLV-I). After 8 weeks, one of them was found to be seroconverted for HTLV-I. Peripheral lymphocytes from the 4 rabbits were cultured in the presence of T-cell growth factor, and a lymphoid cell line with a normal female karyotype was established only from the seroconverted rabbit. This cell line was reactive with a monoclonal antibody to rabbit T-cells and expressed HTLV-I antigens and virus particles.

Animals↗
PubMed1986

Inactivation of lymphocyte-transforming activity of human T-cell leukemia virus type I by heat.

Peripheral blood lymphocytes from 2 normal individuals seronegative for human T-cell leukemia virus type I (HTLV-I) were co-cultured with HTLV-I-producing MT-2 cells that had been heated at 56 degrees for 30 min or exposed to 10,000 rad of X-irradiation. HTLV-I-induced lymphocyte transformation was consistently achieved by co-culture with irradiated MT-2 cells but not by co-culture with heated MT-2 cells. The heat treatment was found to be lethal to both MT-2 cells and the virus. These findings are discussed in terms of their potential clinical application for preventing the transmission of HTLV-I.

Breast Feeding↗
PubMed1986

Reconstruction of chronic massive rotator cuff tears with synthetic materials.

Synthetic materials for repairing experimental massive rotator cuff tears were investigated in 60 rats. The same materials were investigated for massive rotator cuff ruptures in 25 patients. The materials were well tolerated when used for repair of torn segments of the musculotendinous cuff. Of 25 patients with massive rotator cuff tears, 23 had satisfactory functional results. The muscle strength tests on tendons repaired with Teflon felt (which was thicker than the other materials) were superior to results of repairs with other materials; 3-5 mm proved to be the optimum thickness of Teflon felt used for repair of the musculotendinous cuff.

Aged↗
PubMed1985

Adult T-cell leukemia in two siblings. Acute crisis of smoldering disease in one patient.

Two cases of human T-cell leukemia virus (HTLV)-positive adult T-cell leukemia (ATL) in brother and sister are presented. Six of 15 members of this family were seropositive for antibodies for ATL-associated antigens (ATLA). The sister of the ATL patient developed overt ATL after 5 years and 8 months of smoldering ATL. Immunologic examinations during the smoldering phase were normal except for negative skin tests for purified protein derivative. Factors leading to the induction of ATL among HTLV carriers remain to be studied.

Acute Disease↗
PubMed1985

Infectious transmission of human T-cell leukemia virus to rabbits.

A rabbit lymphoid cell line (Ra-1) was established by co-cultivation with a human T-cell line (MT-2) carrying human T-cell leukemia virus (HTLV). The Ra-1 cell line is chromosomally male and is persistently infected with HTLV. Ra-1 cells, with or without mitomycin C treatment, were inoculated intravenously (i.v.) into 3 female rabbits. All 3 animals responded with the production of antibodies to HTLV antigens. Lymphocytes from one of these seroconverters were cultured in the presence of T-cell growth factor (TCGF) and HTLV particles were detected in the TCGF-grown lymphocytes which were chromosomally female. Co-cultivation of lymphocytes from the 2 other seroconverters with lymphocytes from 2 anti-HTLV-negative healthy men gave rise to the establishment of an HTLV-producing T-cell line derived from each individual. Blood transfusion from one of the HTLV-infected rabbits into 2 female rabbits also resulted in the seroconversion of both recipients. An HTLV-carrying lymphoid cell line (Ra-2) was established from one of the transfusion-related seroconverters. The Ra-2 cell line was initially TCGF-dependent but later became TCGF-independent. There results indicate that HTLV can be transmitted to rabbits. These animals may provide a suitable model system for studying the mode of transmission and pathogenicity of HTLV.

Adult↗