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We investigated the mode of action underlying the anti-mycoplasma activity of cationic antimicrobial peptides (AMPs) using four known AMPs and Mycoplasma pulmonis as a model mycoplasma. Scanning electron microscopy revealed that the integrity of the M. pulmonis membrane was significantly damaged within 30min of AMPs exposure, which was confirmed by measuring the uptake of propidium iodine into the mycoplasma cells. The anti-mycoplasma activity of AMPs was found to depend on the binding affinity for phosphatidylcholine, which was incorporated into the mycoplasma membrane from the growth medium and preferentially distributed in the outer leaflet of the lipid bilayer.

Objectives.— To determine the 1-year prevalence of headache and clinical characteristics of primary headaches among school children in South Korea. Background.— Many population-based studies have estimated the 1-year prevalence of headache, migraine, and tension-type headache (TTH). The results of those studies vary in terms of race and region. There have been few epidemiological population-based studies of headache in children and adolescents in Korea. Methods.— We conducted a cross-sectional school-based study of a randomized and proportional sample of 5360 boys and girls. All 180 sampled schools participated in this study. The questionnaires collected demographic data in addition to specific questions about headache according to the International Classification of Headache Disorder criteria, 2nd Edition. Valid questionnaires were returned by 94.1% of the sample population. Modified criteria changed the “duration” of migraine (>1 hour instead of 4 hours). Results.— The prevalence of headache among school children was 29.1% (1465/5039) in South Korea. The prevalence of headache in girls (33.4%) was significantly higher than in boys (24.4%) (P

Pestalotia heterocornis was isolated from soil collected in yew forest and was shown to produce paclitaxel in semisynthetic liquid media. The presence of paclitaxel in the fungal extract was confirmed by FAB mass spectrometry and NMR spectroscopy. The maximum yield of paclitaxel was 31 mg per liter. Optimal paclitaxel production occurred after 5-7 days in a 20-liter scale fermentation at 23 degrees C. These results indicate that P. heterocornis is an excellent candidate for consideration in fermentation technology. Copyright 1999 John Wiley & Sons, Inc.

A series of 5-fluorocytosine derivatives, 5'-deoxy-N-alkyloxycarbonyl-5-fluorocytosine-5'-carboxylic acid 6, were synthesized and evaluated for their antitumor activity.

The structure and properties of the pulp-like aromatic polyamide PPTA fibers prepared directly from a polymerization medium were studied by scanning electron microscopy (SEM), X-ray diffractometry, and polarizing light microscopy. The morphology of the fiber appears significantly different from that of Kevlar and does not reveal a skin-core structure. Regular defect bands and, thus, the regular clustering of the chain ends also could not be observed.