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Biomedical subjects

T Lee

Publications and source records attributed to T Lee.

At least 433 records · Page 24Linked to original sources
PubMed1975

Trans-2-Acetoxycyclobutyltrimethylammonium iodide, a cyclobutane analog of "trans-ACTM".

The (+/-) title compound was prepared to evaluate prior observations that certain acetylcholine congeners derived from cyclobutane are devoid of muscarinic effects. It was prepared by a multistep sequence from trans-2-carbomethoxycyclobutyl methyl ketone. In a guinea pig ileum assay, it was 0.02 times as active as AcCh, and in a dog blood pressure assay, it was 0.09 times as active. In these assays, its (+/-)-cyclopropane congener and AcCh were equally active. This is the first cyclobutane-derived AcCh congener possessing significant muscarinic effect.

Animals↗
PubMed1975

N-Isopropyl derivatives of dopamine and 5,6-dihydroxy-2-aminotetralin.

Secondary and tertiary amino homologs of the title compounds have been prepared, bearing an N-isopropyl group. In peripheral evaluation, certain members of the series exhibited beta-adrenergic agonist effects of lower activity than isoproterenol. N-Methyl-N-isopropyl-5,6-dihydroxytetralin exhibited marked properties consistent with its being an alpha agonist, and it is concluded that introduction of considerable bulk about the nitrogen of a catecholamine does not a priori destroy alpha-agonist effects. The compounds qualitatively paralleled the effects of dopamine in assays based upon direct intrastriatal administration in rats, although they were less potent than dopamine.

2-Naphthylamine↗
PubMed1975

The acute and chronic effects of alcohol on the human immune system.

The immunologic status of 24 male patients admitted for acute alcoholic detoxification was evaluated by in vivo and in vitro parameters. In vivo reactivity, as measured by skin testing with a denovo antigen, dinitrochlorobenzene, as well as a recall antigen, tuberculin, was inact. However, both qualitative and quantitative defects were seen in vitro in the thymus-derived lymphocyte population. These defects were not seen in recovered alcoholics, that is, they appear reversible. The defects seen in the cell-mediated immunity of alcoholics may, in part, be responsible for the high incidence of head and neck cancer observed in this patient population.

Adult↗
PubMed1975

Cellular phosphorylation of 1-beta-D-arabinofuranosylcytosine 5-azacytidine with intact fibrosarcoma and leukemic cells.

The phosphorylation of 1-beta-D-arabinofuranosylcytosine (ara-C) and 5-azacytidine (5-aza-C) by A(T1)C1-3 hamster fibrosarcoma cells and L5178Y murine leukemic cells was studied, using intact cells. The cellular phosphorylation of both these nucleoside analogs appears to follow Michaelis-Menton kinetics. The apparent Km value for ara-C in the fibrosarcoma and leukemic cells was about 40 muM, whereas the apparent Km values for 5-aza-C in these cells were about 1.3 and 0.41 mM, respectively. Deoxycytidine and cytidine were found to be potent competitive inhibitors of the phosphorylation of ara-C and 5-aza-C, respectively, ara-C and 5-aza-C were found to be weak competitive inhibitors of the phosphorylation of deoxycytidine and cytidine, respectively. A clone isolated from the fibrosarcoma cells that was partially resistant to the cytotoxic effects of ara-C exhibited a higher Km value for both ara-C and deoxycytidine than the wild-type fibrosarcoma cells.

Animals↗