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Biomedical subjects

R F Chen

Publications and source records attributed to R F Chen.

79 records · Page 5Linked to original sources
PubMed1965

Fluorescence quantum yield measurements: vitamin B6 compounds.

Quantum yields for pyridoxal, pyridoxamine, and pyridoxamine-5-phosphate at 25 degrees C in neutral aqueous solution were 0.048, 0.11, and 0.14, respectively. The fluorescence efficiencies were highly temperaturedependent, and the compounds were extremely sensitive to light. There were marked discrepancies between the values obtained in this study for quantum yield and fluorescence polarization of pyridoxamine-5-phosphate and the values recently reported by others.

Fluorescence↗
PubMedDate not supplied

Weber syndrome caused by intracerebral hemorrhage in a hemophiliac boy.

A rare occurrence of the Weber syndrome in childhood is reported. The patient was a 7-year-old hemophiliac with recurrent intracerebral bleeding into the right cerebral peduncle and pontine base. Left hemiparesis involving the face and tongue developed and was later accompanied by right oculomotor nerve palsy.

Brain↗
PubMedDate not supplied

Functional roles of human class II antigens in T cell proliferative response. Comparison of the DR and DQ molecules using mouse monoclonal antibodies.

The monoclonal antibody (mAb) NC1 recognizing a monomorphic DR determinant and the anti-DQ mAbs PLM2, PLM9, and PLM12 recognizing polymorphic DQ determinants were produced. NC1 reacted with the H1L1 (DR) and H1L2(DRw52, DRw53 and allelic products) complexes of a DR family, while the specificity of PLM12 was DQw3 (previously called TB21). Both PLM2 and PLM9 reacted with the allodeterminant of TA10 (a subtype of DQw3). These three mAbs immunoprecipitated the same H2L3 complex of a DQ family. With the aid of these mAbs, DR molecules but not DQw3 molecules were detected on monocytes in significant quantities. The functional roles of these class II molecules in the T cell proliferative responses to three soluble antigens (PPD, mite, Candida) and alloantigens were examined by blocking assays in vitro. NC1 almost completely inhibited T cell proliferative responses against both soluble antigens and allogeneic antigens. In contrast, PLM2, PLM9 and PLM12 showed no significant inhibitory effects at all. These results indicate that DR and DQ antigens are different in their functional roles as well as their serological and immunochemical characteristics and tissue distributions; these three soluble antigens and the alloantigen were presented in association with determinants residing predominantly on two forms of NC1-reactive molecule, namely the H1L1 and/or H1L2 complex of a DR family but not in association with the DQw3 allodeterminant on the H2L3 complex of a DQ family.

Antibodies, Monoclonal↗