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M Tamura

Publications and source records attributed to M Tamura.

At least 829 records · Page 46Linked to original sources
PubMed1987

[Effects of smoking on asbestos-related pulmonary and pleural changes].

A radiologic study was made on 184 male asbestos workers in order to determine the effects of smoking on asbestos-related pulmonary and pleural changes. The effects of smoking on the prevalence of pleural changes could not be demonstrated, but the prevalence of pulmonary changes significantly increased with length of smoking history (p less than 0.01). It was found that smoking elevated the prevalence of asbestos-related pulmonary changes. These findings are of great importance in the health management of asbestos workers.

Asbestos↗
PubMed1987

[A case of systemic lupus erythematosus associated with an aneurysm of the lenticulostriate artery].

We describe a patient with established systemic lupus erythematosus (SLE) in whom an intracerebral hemorrhage developed secondary to a ruptured aneurysm of the lenticulostriate artery (LSA). A 24-year-old woman with a four-year history of SLE was admitted to the department of internal medicine of Iwate Medical University for the treatment of lupus nephritis in 1985. She suddenly complained of severe headache and nausea, and soon lost consciousness. The computed tomographic scan revealed intracerebral hemorrhage in the left front-temporal region and subarachnoid hemorrhage. Left common carotid angiography demonstrated a 3 X 3 mm aneurysm of the LSA and displacement of other LSAs and anterior cerebral artery. The incidence of intracerebral hemorrhage in SLE was about ten percent in the reported central nervous system SLE, and it seemed that the prognosis of SLE with intracerebral hemorrhage was poor. The mechanisms of the intracerebral hemorrhage and the aneurysmal formation in SLE seemed to be due to lupus angiitis, but without clinical, radiologic and pathologic correlation. In operation, a ruptured aneurysm without neck was found in LSA and extirpated. In the pathological study, there was transmural angiitis, which fibrinoid necrosis, elastic tissue disruption and infiltration of inflammatory cells were found. Inflammatory cells were chiefly lymphohistiocytic with some polymorphonuclear leukocytes. It seemed that pathologic studies confirmed transmural angiitis with secondary aneurysm formation.

Adult↗
PubMed1987

[Peroxidase].

Explore the source record for details and available documents.

Peroxidases↗
PubMed1987

[Extracorporeal shock wave lithotripsy of urolithiasis].

A total of 159 patients underwent 194 treatments with extracorporeal shock-wave lithotripsy for upper urinary tract calculi between August 4 and November 30, 1986. A single treatment was performed in 76% of the patients with renal stones and 90% of the patients with ureteral stones. Treatment was successful in 153 patients (93%). Seventy percent of the patients with renal stones and 95% of those with ureteral stones were stone-free over the one-month follow-up, while about 15% had small and asymptomatic fragments believed to be passable spontaneously. Only one patient required surgical removal of the calculi due to severe ureteral edema. Adjunctive urological management is required in about 9% of the patients preoperatively or postoperatively. The period of hospitalization averaged about 11 days after treatment and patients usually returned to work within a few days after their discharge. Extracorporeal shock-wave lithotripsy is the preferred form of management for symptomatic ureteral and renal calculi.

Adolescent↗
PubMed1987

Characterization of a second form of NADPH-flavin reductase purified from human erythrocytes.

A second form of the NADPH-flavin reductase with an isoelectric point of 6.1 was purified to homogeneity from human erythrocytes. The enzyme showed NADPH-specific flavin reductase activity when FAD, FMN or riboflavin was used as an electron acceptor. Analyses of the amino acid compositions and immunological reactivities of the enzyme and the other flavin reductase with an isoelectric point of 8.1 revealed that the proteins of these two enzymes are indistinguishable to each other. Tightly bound NADP+, which was reducible by a NADPH-generating system, was specifically found in the second form of the enzyme.

Amino Acids↗
PubMed1986

Structure-function relationship of islet-activating protein, pertussis toxin: biological activities of hybrid toxins reconstituted from native and methylated subunits.

Islet-activating protein (IAP), pertussis toxin, is a hexameric protein composed of an A protomer and a B oligomer, the residual pentamer having such a subunit assembly that two different dimers, dimer 1 and dimer 2, are connected with each other by means of the smallest C subunit. Incubation of IAP with formaldehyde and pyridine-borane produced the modified toxin in which most of the free amino groups were dimethylated. The methylated and nonmethylated (native) IAP were disintegrated into their respective constituent components, which were then cross combined to reconstitute hybrid toxins with the original hexameric structure. The binding of the B oligomer to the mammalian cell surface via dimer 2 was, but the binding via dimer 1 was not, seriously impaired by methylation of amino groups in the protein. The binding of the B oligomer allowed the A protomer to enter cells and to catalyze ADP-ribosylation of a membrane Mr 41 000 protein. The diverse biological activities of IAP occurring by this mechanism were mimicked by not only methylated IAP but also all hybrid toxins, indicating that the free amino groups in the protein were not essential for the enzyme activity of the A protomer and that the A protomer was able to enter cells if the B oligomer bound to cells "monovalently" via dimer 1. An additional effect of the B oligomer binding, i.e., the direct stimulation, without the transport of the A protomer, of cells leading to mitosis in lymphocytes in vitro or increases in circulating lymphocytes in vivo, was not mimicked by hybrid toxins containing methylated dimer 2.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Diphosphate Ribose↗
PubMed1986

Purification and characterization of human granulocyte colony-stimulating factor (G-CSF).

A colony-stimulating factor (CSF) has been purified to homogeneity from the serum-free medium conditioned by one of the human CSF-producing tumor cell lines, CHU-2. The molecule was a hydrophobic glycoprotein (mol. wt 19,000, pI = 6.1 as asialo form) with possible O-linked glycosides. Amino acid sequence determination of the molecule gave a single NH2-terminal sequence which had no homology to the corresponding sequence of the other CSFs previously reported. The biological activity was apparently specific for a neutrophilic granulocyte-lineage of both human and mouse bone marrow cells with a specific activity of 2.7 X 10(8) colonies/10(5) non-adherent human bone marrow cells/mg protein. The purified CSF can be regarded as a G-CSF of human origin and will become a useful material for investigation of regulatory mechanisms of human granulopoiesis.

Amino Acids↗
PubMed1986

Characterization of glycoproteins of viruses causing hemorrhagic fever with renal syndrome (HFRS) using monoclonal antibodies.

Viruses causing hemorrhagic fever with renal syndrome (HFRS) encode two glycoproteins, G1 and G2. For determination of the biological functions of these glycoproteins, we isolated 15 hybridomas secreting monoclonal antibodies directed against the glycoproteins of the B-1 and Hantaan viruses (HV). From results of neutralizing and hemagglutination inhibition (HI) tests, and studies on the antigenic reactivities of the antibodies with other HV-related viruses by immunofluorescence, we classified these hybridoma clones into two groups producing antibodies to the G1 proteins of the B-1 virus, six groups producing antibodies to G2 proteins of the B-1 virus, and four groups producing antibodies to the G2 protein of HV. Of the antibodies to G2 produced by 12 clones, groups A and B had high HI activity with HV-related virus cross-reactivity and moderate neutralizing activity, group C had moderate HI activity with virus specificity but low neutralizing activity, group G had high neutralizing activity and low HI activity, and five other groups had little or no HI or neutralizing activity. Group A reacting with G1 protein had low level of both neutralizing and HI activity, while group B had no HI activity. One clone of monoclonal antibody had high neutralizing activity and no HI activity, but it did not react with either polypeptide by immunoprecipitation followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis or by the immunoblotting method. These data suggest that both glycoproteins are the targets of neutralizing antibodies. Furthermore, the results indicate that the antigenic determinants with hemagglutination activity are mainly on the G2 protein, and that the domains related to neutralizing activity and to HI activity are separate.

Animals↗