PubMed Health⌕ Search

Biomedical subjects

M Kaneda

Publications and source records attributed to M Kaneda.

At least 181 records · Page 10Linked to original sources

Piperazinomycin, a new antifungal antibiotic. I. Fermentation, isolation, characterization and biological properties.

A new antifungal antibiotic, named piperazinomycin, was isolated from the cultured broth of Streptoverticillium olivoreticuli subsp. neoenacticus. The antibiotic was obtained from the mycelial cake by extraction with methanol and also from the broth filtrate by adsorption on Amberlite XAD-2 and subsequent elution with aqueous acetone. The antibitoic is of basic and lipophilic nature and can be extracted with methyl isobutyl ketone at alkaline pH. Its purification was carried out by column chromatography on Sephadex LH-20 and then on Sephadex G-15 followed by preparative thin-layer chromatography on silica gel. The molecular formula of piperazinomycin was determined to be C125H20NsO2 by high resolution mass spectrum and the spectroscopic and chemical properties were examined. Piperazinomycin showed inhibitory activity against fungi and yeasts, especially against Trichophyton.

Antifungal Agents↗

Correlation between the molecular structure of N-alkylureas and N-alkylthioureas and their teratogenic properties.

Eleven urea compounds were administered individually as a single oral dose to rats either on day 12 or 14 and to mice on day 10 of pregnancy. 1-Methylurea and 1-ethylurea were not teratogenic in either of the animal species. Administration of 1-methylthiourea and 1-ethylthiourea, however, resulted in high incidences of malformations in the rat but not in the mouse fetuses. The types of malformation were similar to those produced by the known teratogen ethylenethiourea. Methylated ureas such as 1,3-dimethylurea, 1,3-dimethylthiourea, 1,1,3,3-tetramethylurea, and 1,1,3,3-tetramethylthiourea were fetotoxic and produced malformations in the tail, palate, or extremities of the surviving rat and/or mouse fetuses. These findings suggest that the teratogenic properties of N-alkylureas can be categorized into two groups, i.e., mono-alkylated thioureas and methylated ureas or thioureas.

Abnormalities, Drug-Induced↗

Adsorption of 14C-labeled gramicidin S on cell of bacteria.

Gramicidin S (GS) containing 14C-labeled proline was synthesized by a solid-phase method, and the labeled GS dihydrochloride was obtained as crystals. The labeled GS exhibited same antibacterial activity as natural GS. Strains sensitive to GS (B. subtilis and S. aureus) and an insensitive strain (E. coli) were treated with the labeled GS, and the amount of the labeled GS adsorbed on the cells was measured. GS was adsorbed rapidly on the cells of the sensitive strains; the amount adsorbed increased linearly with GS concentration up to 1-1.5 microgram/ml, and at a lower rate at above 1.5 microgram/ml. GS molecules covered most of the cell surface at the minimum inhibitory concentration of 1.5 microgram/ml; the number of molecules adsorbed per cell was 1.3-1.4 x 10(6). No GS was adsorbed by the insensitive strain.

Adsorption↗

Comparative studies on alveolar macrophages and polymorphonuclear leukocytes. I. H2O2 and O2- generation by rabbit alveolar macrophages.

The oxidative metabolism of rabbit alveolar macrophages (A-MO) was compared with that of rabbit polymorphonuclear leukocytes (PMN) with respect to H2O2 generation by intact cells or subcellular fractions. Rabbit PMN exhibited an increase in the oxygen uptake and a marked release of H2O2 upon addition of heat-killed E. coli in the presence and absence of opsonin. However, rabbit A-MO exhibited an increase in the oxygen uptake upon addition of E. coli only in the presence of anti-E. coli serum as an opsonin, whereas a very small amount of H2O2 release was observed during ingestion of the opsonized E. coli. The generation of O2- and H2O2 by a granule-rich fraction isolated from phagocytosing PMN was larger than that by a similar fraction isolated from resting PMN. However, there was no significant difference in O2- and H2O2 generation by the granule fractions between phagocytosing and resting A-MO in the presence of either NADH or NADPH. In contrast to the granule fraction of rabbit PMN, the O2- and H2O2 generating activities in the A-MO granule fraction were higher in the presence of NADH than in the presence of NADPH. The rates of NADH and NADPH oxidation by both A-MO and PMN granule fractions were measured with and without addition of Mn2+ to the assay medium. The effect of Mn2+ on the NAD(P)H oxidase was found to differ between rabbit A-MO and PMN.

Animals↗

Comparative studies on alveolar macrophages and polymorphonuclear leukocytes. II. The ability of guinea pig alveolar macrophages to produce H2O2.

Guinea pig alveolar macrophages (A-M0) were studied with respect ot the phagocytic metabolism: the respiratory burst and its KCN sensitivity, the ability to generate H2O2, and myeloperoxidase (MPO) activity. Only fifty percent of the O2 uptake by A-M0 samples during phagocytosis was inhibited by the addition of 1 mK KCN. Guinea pig A-M0 released H2O2 amounting to 7.7 and 12.5 nmol/min/10(7) cells upon addition of E. coli in the absence and presence of anti-E. coli antibody, respectively. Myristic acid, an effective membrane activator, induced a marked release of H2O2 amounting to 16.1 nmol/min/10(7) cells. We observed a high MPO activity in some alveolar lavage cells which contained a large number of polymorphonuclear leukocytes (PMN), but none at all in preparations containing fewer PMN. The MPO activity detected did not seem to be due to A-M0, but to the PMN contained in the preparations.

Animals↗