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Biomedical subjects

Y Shimoyama

Publications and source records attributed to Y Shimoyama.

84 records · Page 5Linked to original sources
PubMed1987

A functioning intrapericardial paraganglioma (pheochromocytoma).

A patient with a functioning intrapericardial paraganglioma (pheochromocytoma) that was located at the root of the aorta overlying the right coronary artery and adherent to the right ventricular wall is reported. The tumour was successfully removed under total cardiopulmonary bypass without inducing cardiac arrest.

Female↗
PubMed1987

Monoclonal antibody highly sensitive for the detection of ras p21 in immunoblotting analysis.

Four murine monoclonal antibodies (NCC-RAS-001, -004, -005, -017) reactive with ras p21 were produced by using recombinant c-Ha-ras p21 as an immunogen. Among these antibodies, NCC-RAS-004 was extremely sensitive when used in immunoblotting analysis, facilitating semiquantitative detection of c-Ha-, c-Ki- and N-ras p21 in cell and tissue lysates. In cells carrying a point-mutationally activated ras, p21 with abnormal mobility upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis was clearly detected.

Antibodies, Monoclonal↗
PubMed1987

[Antitumor activity of cisplatin and carboplatin against human tumor xenografts serially transplanted into nude mice--with special reference to gastric carcinomas].

Experimental chemotherapy with cisplatin and carboplatin was performed against nine human tumor xenografts serially transplanted into nude mice. Tumors used for the experiment were seven gastric (St-4, St-15, St-40, H-111, SC-2-JCK, SC-6-JCK and Exp-4), one breast (MX-1) and one colon (Co-4) carcinomas. Cisplatin 9 mg/kg and carboplatin 100 mg/kg were administered intraperitoneally (ip). Carboplatin 25 mg/kg was also given ip 4 times every 4 days. The efficacy rates of cisplatin and carboplatin by bolus injection were 77.8% and 66.7% respectively with no statistically significant differences. However, carboplatin was found more effective when given by bolus. The antitumor spectra of both drugs were similar. From these results, these two platinum compounds seemed to be effective against human gastric carcinomas.

Adenocarcinoma↗
PubMed1978

Molecular motion and order in oriented lipid multibilayer membranes evaluated by simulations of spin label ESR spectra. Effects of temperature, cholesterol and magnetic field.

A simulation method to interpret electron spin resonance (ESR) of spin labelled amphiphilic molecules in oriented phosphatidylcholine multibilayers in terms of a restricted motional model is presented. Order and motion of the cholestane spin label (3-spiro-doxyl-5alpha-cholestane) incorporated into egg yolk phosphatidylcholine, dipalmitoylphosphatidylcholine and dimyristoylphosphatidylcholine, pure and in mixture with cholesterol, were studied at various temperatures. With egg yolk phosphatidylcholine identical sets of motional parameters were obtained from simulations of ESR spectra obtained at three microwave frequencies (X-, K- and Q-band). With dipalmitoylphosphatidylcholine and dimyristoylphosphatidylcholine analyses of the spectra show that phase transitions occur in samples containing up to 30 mol % cholesterol. The activation energy for the motion of the spin label is about three times larger above than below the phase transition, indicating a more collective motion in the lipid crystalline state than in the gel state. In the liquid crystalline state the activation energy is larger in the pure phosphatidylcholines than with cholesterol added. Additions of cholesterol to egg phosphatidylcholine induces a higher molecular order but does not appreciably affect correlation times. This is in contrast to dipalmitoylphosphatidylcholine where both order and correlation times are affected by the presence of cholesterol. The activation energies follow the same order as the transition temperatures: dipalmitoylphosphatidylcholine greater than dimyristoylphosphatidylcholine greater than egg yokd phosphatidylcholine, suggesting a similar order of the cooperativity of the motion of the lipid molecules. Magnetic field-induced effects on egg phosphatidylcholine multibilayers were found at Q-band measurements above 40 degrees C. The cholestane spin label mimics order and motion of cholesterol molecule incorporated into the lipid bilayers. This reflects order and motion of the portions of the lipid molecules on the same depth of the bilayer as the rigid steroid portions of the intercalated molecules.

Chemical Phenomena↗
PubMedDate not supplied

Neuroendocrine carcinoma in the nasal cavity of ten dogs.

Neuroendocrine (NE) carcinoma was diagnosed in 10 dogs. In six cases examined by cephalometric radiography and computerized tomography, a large mass was seen to fill the nasal cavity. Histopathologically, sheets, nests or ribbons of neoplastic cells were separated by delicate or thick fibrovascular stroma. The neoplastic cells were round, oval, or spindle-shaped; cytoplasmic granules and hyperchromatic nuclei with prominent nucleoli were present. Neoplastic cells were invariably immunohistochemically positive for cytokeratin (CK) AE1/AE3, neuron-specific enolase, chromogranin A and vasoactive intestinal polypeptide. Eight dogs were positive for S100 protein, seven for synaptophysin, five for protein gene product 9.5, two for somatostatin, and one for Leu-7. Immunolabelling gave negative results for CK 8, CK 19, calcitonin, calcitonin gene-related polypeptide, neurofilaments, serotonin, gastrin and glial fibrillary acidic protein. Ultrastructurally, the neoplastic cells contained a large number of round, membrane-bounded, densely-cored granules corresponding to neurosecretory granules. These observations were consistent with the neuroendocrine nature of the carcinomas.

Animals↗
PubMedDate not supplied

Preferential expression of B7.2 (CD86), but not B7.1 (CD80), on B cells induced by CD40/CD40L interaction is essential for anti-DNA autoantibody production in patients with systemic lupus erythematosus.

OBJECTIVE: B7 (CD80/CD86) molecules are over-expressed in patients with SLE. However, it is not clear whether CD80/CD86 molecules are involved in the pathogenic autoantibody production specifically or in the polyclonal antibody production in human SLE. The present study was carried out to characterize B7 molecules on B cells in autoantibody production. METHODS: Expression of costimulatory molecules was analyzed by RT-PCR and two-color immunofluorescence staining. Purified B cells were co-cultured with T cells in the presence of anti-costimulatory molecule antibody. RESULTS: Excessive expression of CD86 and CD80 molecules was evident on freshly isolated B cells in patients with SLE. Normal B cells did not express CD86 molecules spontaneously and expressed it after co-culture with activated T cells. CD86 expression on normal and SLE B cells induced by the activated T cells was inhibited by the addition of anti-CD40L into the cell culture. Furthermore, CD40L expression on T cells upon activation was enhanced in SLE patients. Anti-DNA antibody production by SLE B cells in the presence of activated T cells was markedly inhibited by anti-CD86, but not anti-CD80. Anti-CD86 treatment inhibited polyclonal Ig and anti-SS-A antibody production of SLE B cells, suggesting the preferential involvement of CD86 in polyclonal antibody production. CONCLUSION: SLET T cells express CD40L excessively, and the CD40/CD40L pathway is involved in the CD86 over-expression of SLE B cells; thus T cell abnormality is at least partially involved in B cell hyperactivity. Enhanced CD86 expression of B cells by CD40L is essential for polyclonal antibody production.

Adolescent↗