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S H Cheon

Publications and source records attributed to S H Cheon.

22 records · Page 2Linked to original sources

Flow cytometric analysis of DNA ploidy in primary non-small cell carcinoma of the lung in Korea.

Flow cytometrically determined nuclear DNA content has been measured on 74 formalin-fixed, paraffin embedded specimens of non-small cell carcinoma of the lung. Of the 60 tumors that were successfully analyzed, 32 (53%) were diploid and 28 (47%) were aneuploid. The mean DNA index of aneuploid tumor was 1.5 +/- 0.25, ranging from 1.1 to 2.0. There was no significant correlation between DNA ploidy and the patient's clinical characteristics, histology of tumor, nodal status or tumor stage. Tumor ploidy was not found as a prognostic determinant in non-small cell carcinoma of the lung in this study.

Adult↗

Detection of Mycobacterium tuberculosis in clinical samples from patients with tuberculosis or other pulmonary diseases by polymerase chain reaction.

Polymerase chain reaction (PCR) using primers targeting the IS6110 repetitive sequence was employed to detect Mycobacterium tuberculosis in 228 samples from patients with tuberculosis or other pulmonary diseases and controls, and the results were compared with culture and clinical findings. None of culture negative samples from 17 healthy controls were PCR positive. Of 109 active tuberculosis patients under chemotherapy, 88 (80.7%) were PCR positive and were significantly higher than 63 (57.8%) positive by culture. Fifty-nine (93.7) of 63 culture positive and 29 (63.0%) of 46 culture negative specimens contained M. tuberculosis detectable by PCR. In 41 specimens from inactive tuberculosis patients who visited to the chest clinic because of chest problems, 16 (39.0%) also gave PCR positive results. In addition, 14 (46.7%) of 30 specimens submitted for M. tuberculosis culture from patients with pulmonary diseases were PCR positive. Presumptive diagnosis of these PCR positive patients was bronchitis, pneumonia, bronchial asthma, etc. Therefore, this study suggests that PCR is sensitive and specific in detecting M. tuberculosis in clinical specimens. However, the interpretation of the PCR results in specimens from patients with pulmonary diseases should be done cautiously in areas with a high prevalence of tuberculosis.

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Synthesis and pharmacology of a novel class of long-lasting PAF receptor antagonists.

Several new charged PAF receptor antagonists were prepared, where the phosphate moiety has been replaced by a methylsulfonylcarbamoylpyridinium moiety, and evaluated for duration of inhibitory activity against PAF-induced bronchoconstriction and hemoconcentration in the guinea pig. One of these compounds (1d; SDZ 64-619) has shown potency and duration of inhibition in the range of CV-6209 (1c).

Adult↗

Cyclic oxygen analogues of alkyl-lysophospholipids. Synthesis and neoplastic cell growth inhibitory properties.

Ether phospholipids have demonstrated both in vitro and in vivo activity against a wide variety of tumor cell lines. The known cyclic ether phospholipid, SRI 62-834, was used as the model to prepare eight novel phospholipids containing a cyclic ether. All of the compounds were as effective as ET-18-OCH3 in their ability to activate macrophage-induced cytotoxicity against the Abelson-8.1 tumor cell line but varied in their direct cytotoxic effects. One of the new compounds, SDZ 62-406, was selected for in vivo studies and showed oral and i.v. activity in the mouse MethA fibrosarcoma model in the same range as ET-18-OCH3. No correlation was found between the direct or macrophage-activated cytotoxicity and the ability of the compounds to inhibit or promote platelet-activating factor (PAF)-induced aggregation of human platelets.

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