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Biomedical subjects

M Tsuchiya

Publications and source records attributed to M Tsuchiya.

At least 487 records · Page 27Linked to original sources
PubMed1984

Repeated micro-monocyte adherence inhibition assay: a new technique of leukocyte adherence inhibition to detect tumor immunity in patients with hepatoma.

A microplate leukocyte adherence inhibition (micro-LAI) assay was performed with peripheral blood mononuclear cells obtained from patients with hepatoma and control subjects (including healthy donors and patients with other diseases). Cell extracts of human hepatoma cells (HCC-M) and human hepatic cells (Chang liver cell) in tissue culture were prepared by sonication followed by centrifugation. The supernatants of these two cell lines were used as a specific antigen and a nonspecific antigen, respectively. It was found that monocytes were major indicator cells and that monocytes produced an LAI reaction in the absence of lymphocytes. Therefore, a repeated microplate monocyte adherence inhibition (MAI) assay was developed, in which the monocyte population of adherent cells is increased by removing nonadherent cells after an initial assay in fetal calf serum-containing medium without test antigens, and monocytes are counted selectively as peroxidase-positive cells in a subsequent second assay with test antigens. With regard to sensitivity and reproducibility, the repeated micro-MAI assay is superior to a micro-MAI assay in which the initial assay is omitted although monocytes are selectively counted. With this simple and sensitive technique a hepatoma-associated immune response to the extract of HCC-M was detected in 16 out of 22 patients (73%) with hepatoma, whereas the false-positive rate was 7% (3/41) in all control subjects.

Carcinoma, Hepatocellular↗
PubMed1984

Improved assay for alcohol dehydrogenase activity in serum by centrifugal analysis.

We describe an improved method for determination of alcohol dehydrogenase (EC 1.1.1.1) activity in 60 microL of human serum, based on conversion of ethanol to acetaldehyde with simultaneous reduction of NAD+ in glycine NaOH buffer (pH 9.0) at 37 degrees C in a centrifugal analyzer. The final concentration of NAD+ was 10 mmol/L and ethanol was 20 mmol/L. The dilution curve was linear with enzyme activity up to 200 U/L, and results by this method correlated well with those by a manual method (N Engl J Med 279: 241-248, 1968). Within-run precision (CV) was 0.9 to 8.2% over the range of 4.5 to 88.1 U/L, and day-to-day precision was 5.4 to 5.6%. In sera from 198 healthy individuals, mean alcohol dehydrogenase activity was 1.6 (SD 1.2, range 0-5) U/L. To evaluate the clinical utility of determining alcohol dehydrogenase, we measured the activity of alanine aminotransferase and alcohol dehydrogenase in sera from 470 patients with various diseases in our hospital, and found that results for the two enzymes did not correlate well.

Adult↗
PubMed1984

Detection of antibodies to Chang liver cell in sera from patients with chronic liver diseases by 125I-labelled protein A binding assay and the effect of prednisolone and 6-mercaptopurine treatment on the level of the antibodies.

Antibody binding to living Chang liver cell was measured in sera from 71 patients with various chronic liver diseases using 125I-labelled protein A binding assay. The level of antibody binding to Chang liver cell was significantly elevated in sera from patients with chronic active hepatitis (CAH), chronic persistent hepatitis (CPH) and liver cirrhosis as compared to those from healthy donors, but not in sera from patients with fatty liver. There was no detectable antibody binding to HeLa cells in those sera. The antibody binding to Chang liver cell was blocked by a human liver specific protein (LSP) preparation. The levels of antibody binding to Chang liver cell were significantly higher in patients with CAH than patients with CPH. On the other hand, the level of antibody binding to Chang liver cell was significantly decreased in sera from patients with CAH after a treatment with prednisolone (PSL) for 2 months and a subsequent combined administration of 6MP and a maintenance dose of PSL for 1 month. These results suggest that antibodies to Chang liver cell are closely correlated with the activity of chronic liver disease and that PSL and 6MP treatment can reduce the level of the antibodies.

Antibodies↗
PubMed1984

Characterization of thymus cells in hyperplastic thymuses in patients with myasthenia gravis and ulcerative colitis with monoclonal antibodies.

Recently, increasing attention has been paid to thymic relevance to pathogenesis in some autoimmune diseases. In this report, the thymus cells from 7 patients with myasthenia gravis (MG) and 6 patients with ulcerative colitis (UC), who had undergone thymectomy for complication of thymic hyperplasia, were studied. The thymus cells were characterized with monoclonal antibodies (Anti-Leu-2a and Anti-Leu-3a) which define human T-cell surface antigens. Although the control thymus consisted of 82-94% of thymocytes which were reactive with Anti-Leu-2a and 90-95% of cells reactive with Anti-Leu-3a, in UC patients both Leu-2a positive thymus cells (38-56%) and Leu-3a positive cells (68-82%) were decreased. Concerning MG thymocytes, Leu-2a positive cells were also decreased (66-81%), but the percentage of Leu-3a positive cells did not show a remarkable change (86-90%) compared with control thymocytes. Considering the above results and many reports telling functional and populational abnormalities of peripheral immunocompetent cells, the process of intra-thymic T-cell maturation may be impaired in these autoimmune diseases.

Adult↗
PubMed1984

Induction of impaired activation of lymphocytes by suppressive factor in Crohn's disease patients.

Lymphocyte proliferative response to phytohemagglutinin (PHA) and relevance of serum factors to the response were studied in 12 patients with Crohn's disease (CD). The lymphocyte proliferative response was markedly reduced in patients with Crohn's disease (S.I. = 38.8 +/- 36.8) (mean +/- SD), as compared with normal controls (S.I. = 100.6 +/- 28.6) (p less than 0.01). In addition, the effect of sera from patients with CD or 10 patients with ulcerative colitis (UC) who had extremely impaired lymphocyte responsiveness to PHA on the proliferative response of normal lymphocytes to PHA was also measured. Sera from CD patients had a marked suppressive effect on the blastogenesis of normal lymphocytes (S.I. = 46.4 +/- 28.5), as compared with normal sera (S.I. = 126.2 +/- 14.7) (p less than 0.001). On the other hand, UC sera did not suppress the blastogenesis of normal lymphocytes (S.I. = 114.9 +/- 27.7). Moreover, serum immunosuppressive acidic protein (IAP) levels in patients' sera were measured by single radial immunodiffusion assay. A marked increase in serum IAP levels was revealed both in CD patients (780 +/- 470 micrograms/ml) and in UC patients (601 +/- 278 micrograms/ml), as compared with normal controls (376 +/- 92 micrograms/ml) (p less than 0.001). But there was no precise correlation between the suppressive effect of sera and serum IAP levels in patients with CD. Thus, we demonstrated an impairment of the lymphocyte responsiveness to PHA in CD patients and the possible existence of immunosuppressive factors which is not identical with IAP in the sera from patients with CD.

Adult↗
PubMed1983

Decreased natural killer activity in patients with liver cirrhosis.

Natural killer (NK) activity of peripheral blood mononuclear cells from patients with non-alcoholic liver cirrhosis (LC) (30 cases), patients with other, non-malignant diseases (41 cases), and healthy subjects (36 cases) were investigated using 51Cr-labelled CCRF-CEM and K562 target cells. NK activity in patients with LC was lower than that in healthy subjects and that in patients with other, non-malignant diseases. The differences were statistically significant by Student's t-test and the Wilcoxon rank test. There was no difference of NK activity between serologically hepatitis B surface antigen (HBsAg)-positive and -negative patients.

Adult↗
PubMed1983

ADP-ribosylation regulates the phosphorylation of histones by the catalytic subunit of cyclic AMP-dependent protein kinase.

Phosphorylation of whole histones from calf thymus by the catalytic subunit of cyclic AMP-dependent protein kinase was markedly reduced when the histones were ADP-ribosylated. NAD, nicotinamide or free ADP-ribose molecule did not suppress the phosphorylation. Urea gel electrophoretic analyses of the phosphorylated histones which had already been ADP-ribosylated revealed that the suppression of phosphorylation occurred in both H1 and core histones. Therefore, the possibility that ADP-ribosylation may regulate the phosphorylation of histones phosphorylation in nuclei warrants further investigation.

Adenosine Diphosphate Ribose↗
PubMed1983

Establishment of a cell line (HCC-M) from a human hepatocellular carcinoma.

A continuous human cell line was established from a hepatocellular carcinoma of an HBsAg-positive Japanese male. The cell line, designated HCC-M, grows as an adhering monolayer with a doubling time of 24 h in medium RPMI-1640 supplemented with 10% FCS and grows with 30% clonal efficiency in soft agar. The cells have been shown by light and electron microscopy to be of epithelial type. When they were transplanted subcutaneously into the back of athymic nude mice (BALB/c, nu/nu), tumors developed at the sites of inoculation, which were shown to be hepatocellular carcinoma, similar in morphology to the original tumor from which they were derived. HCC-M had a chromosome mode of 63 with five identifiable marker chromosomes. HCC-M produced albumin at the 10th passage but this property was lost by the 30th passage. This cell line has not secreted alpha-fetoprotein. Hepatitis B viral particles or HBsAg have not been demonstrated in the cells from the primary culture nor in several subsequent subcultures tested.

Adult↗
PubMed1983

Mono (ADP-ribosyl)ation of hen liver nuclear proteins suppresses phosphorylation.

The phosphorylation of nuclear proteins from hen liver nuclei was suppressed under conditions of incubation with NAD. The reconstituted protein kinase assay system containing heat-treated and subsequently ADP-ribosylated nuclei and NI type protein kinase revealed that the ADP-ribosylated nuclear proteins are poor acceptors for the phosphorylation reaction. Therefore, mono(ADP-ribosyl)ation may contribute to the regulation of phosphorylation reaction in nuclei.

Adenosine Diphosphate Ribose↗