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Biomedical subjects

T Ishida

Publications and source records attributed to T Ishida.

At least 1,045 records · Page 58Linked to original sources
PubMed1987

Survey of nonhuman primates for antibodies reactive with Epstein-Barr virus (EBV) antigens and susceptibility of their lymphocytes for immortalization with EBV.

The susceptibility to transformation with Epstein-Barr virus (EBV) and the prevalence of antibodies reactive to EBV were examined in 43 primate species. In vitro EBV infection was revealed in lymphocytes from Old World monkeys, including patas monkeys and the colobines, as well as in lymphocytes from the apes. Antibodies reactive to EBV-early antigen/viral capsid antigen (EA/VCA) were detected in all the species of Old World monkeys and apes examined and in two out of seven species of New World monkeys.

Animals↗
PubMed1987

On the structure-activity relationship of histamine H2-receptor antagonists based on the X-ray crystal structures and 1H-NMR spectra of amidine derivatives.

The conformation of six amidine compounds, which possess a common 3-[(4-thiazolyl)methylthio]propionylamidine framework but exhibit different activities as histamine H2-receptor antagonists, have been subjected to both single crystal X-ray structural and 1H-NMR analyses. The X-ray studies suggest a correlation between antagonist activity and the relative spatial orientation of the thiazolyl and amidine nitrogen atoms. This correlation is supported by a comparison of the conformations observed for the amidines with those of other H2-receptor antagonists and reveal that a folded conformation, specifically the NH...N intramolecular hydrogen-bonded configuration, is important for antagonist activity. The 1H-NMR measurements on the active amidine compounds show that the intramolecular NH...N bond is likely to be present in solution.

Amidines↗
PubMed1987

[Clinicopathological studies of nuclear DNA distribution in colorectal cancer].

The nuclear DNA content of paraffin-embedded materials was measured by microfluorometry in 108 colorectal (59 colon and 49 rectal) cancers and 29 metastatic liver tumors from the colorectum. The classification of the nuclear DNA distribution is as follows: Low ploidy, 10% greater than over 4C; intermediate ploidy, 10% less than or equal to over 4C and 10% greater than over 6C; high ploidy, 10% less than or equal to over 6C. In primary lesions, thirty-one (29%) were found to contain cells with high ploidy. The ploidy pattern was not related to pathological stage. However, in curatively resected cases, only 24% of patients with high ploidy survived 10 years. This 10 year-survival rate was significantly lower as compared with 80% and 88% of patients with intermediate and low ploidy, respectively (p less than 0.05). In non-curatively resected cases, no patients with high ploidy survived 2 years, although 21% and 67% of patients with intermediate and low ploidy survived, respectively. In metastatic liver lesions, eleven materials (42%) were found to contain cells with high ploidy. Prognosis of patients with high ploidy was worse than that with intermediate and low ploidy (p less than 0.05). These observations suggest that the nuclear DNA distribution in colorectal cancers may be an important prognostic factor, independent of pathological stage.

Colonic Neoplasms↗
PubMed1987

Cross-reactivity between human and feline Ia antigens, using a monoclonal antibody HLA-D.m1.

A murine monoclonal antibody HLA-D.m1 produced against human Ia antigens which react with 10% to 30% of human peripheral-blood mononuclear cells was found to react with greater than 90% of feline mononuclear cells. The antigen was not expressed on granulocytes. By direct immunofluorescence, 7% to 41% of feline lymphocytes expressed surface immunoglobulins. In mixed-lymphocyte reaction, the addition of antibody HLA-D.m1 to cultures abolished proliferation. These studies indicate that most feline peripheral-blood mononuclear cells express Ia-like antigens.

Animals↗
PubMed1987

Characterization of feline T and B cells.

Feline peripheral-blood lymphocyte populations (n = 22) were examined for the following markers: rosette formation with guinea pig erythrocytes (GPE-T cells), rosette formation with human RBC (HRBC-T cells), rosette formation with sheep RBC, mixed rosette formation with GPE-T cells and HRBC-T cells (total T cells), erythrocyte antibody-complement rosettes, and surface immunoglobulin. An average of 28% +/- 7% (range, 16% to 39%) of the feline lymphocytes formed rosettes with GPE-T cells, and 27% +/- 7% (range, 11% to 36%), with HRBC-T cells. An average of 57% +/- 9% (range, 33% to 75%) of the lymphocytes formed mixed rosettes. The erythrocyte antibody-complement rosette-forming cells and surface immunoglobulin-bearing cells were found in peripheral blood lymphocytes (10% +/- 6% and 24% +/- 8%, respectively). The murine monoclonal antibodies OKT 11 and HuLy-m1, specific for a framework determinant of human E-rosette receptor antigens, cross-reacted with feline cell membrane molecules recognizing a bimolecular complex (45,000 to 50,000 daltons) similar to that described in persons. We investigated the distribution of these E-rosette receptor-like antigens on feline lymphocytes. By complement-mediated lymphocytotoxicity, about 30% of the feline lymphocytes expressed the antigens. When lymphocytes were treated with HuLy-m1 antibody, spontaneous rosette formation with HRBC-T cells was significantly inhibited.

Animals↗
PubMed1986

Stacking and hydrogen bonding interactions between phenylalanine and guanine nucleotide: crystal structure of L-phenylalanine-7-methylguanosine-5'-monophosphate complex.

The crystal structure of title complex has been analyzed by X-ray diffraction method as a model for elucidating the possible interaction between the phenylalanyl residue of proteins and the N7-protonated or methylated guanine base of nucleic acids. The guanine base is associated with the benzene ring of phenylalanine by stacking interaction, and further connected with the carboxyl group by the formation of a pair of hydrogen bonds. These two interaction modes are suggested to be responsible for the specific recognition of base sequence by protein.

Carrier Proteins↗
PubMed1986

[Serum thyroglobulin levels in patients with thyroid tumor].

Serum thyroglobulin (Tg) levels were measured in 15 normal volunteers, 69 patients with differentiated thyroid carcinoma, 22 with adenoma, 45 with adenomatous goiter, 5 with functioning adenoma and 24 with Graves' disease, utilizing a double antibody radioimmunoassay technique. Serum Tg levels in the normal volunteers were found to be less than 30 ng/ml as determined from their mean value, i.e., 16.9 +/- 13.4 ng/ml (mean + 2SD), whereas serum Tg in the patients with various thyroid disorders showed significantly elevated (P less than 0.01). Serum Tg of patients with differentiated thyroid carcinoma without distant metastasis was 71 +/- 7 ng/ml (mean +/- SE), that in adenoma 124 +/- 22 ng/ml, that in adenomatous goiter 147 +/- 19 ng/ml, that in functioning adenoma 120 +/- 41 ng/ml, and that in Basedow disease 122 +/- 22 ng/ml. Furthermore, it appears that Tg concentration in serum is correlated with the size of the nodules in differentiated thyroid carcinoma (P less than 0.01) and benign nodules (P less than 0.05). Present results suggest that thyroid tumor also release Tg into serum in addition to Tg stored in the normal tissue. Furthermore, the level of circulating Tg in patient is not correlated to the level of serum TSH. In treated differentiated thyroid carcinoma, serum Tg levels were markedly reduced (21 +/- 2 ng/ml) in patients with no evidence of either recurrences or metastases, but significantly elevated in those with recurrences and/or metastases (257 +/- 109 ng/ml). Therefore, serum Tg measurements in the follow-up of patients treated for differentiated thyroid carcinoma are useful in the search for recurrences or metastases.

Adenoma↗