Antibiotic activity of isoxazolylnaphthoquinone imines on mice infected with Staphylococcus aureus

I. ALBESA, P. BOGDANOV, A. ERASO, N.R. SPERANDEO AND M.M. DE BERTORELLO. 1995. The antibiotic activity of new synthetic isoxazolylnaphthoquinone imines was studied. Pseudomonas aeruginosa ATCC 27853 and Escherichia coli ATCC 25922 were resistant to the four compounds studied (MIC > 128 µg ml⁻¹), but Staphylococcus aureus ATCC 25923, ATCC 29213 and 30 clinical isolates of Staph. aureus were inhibited by 2-hydroxy- N -(3,4-dimethyl-5-isoxazolyl)-1,4-naphthoquinone-4-imine (I). This compound diminished bloodstream infection of mice injected i.m. with Staph. aureus; septicaemia decayed significantly when I was applied at the beginning of the infection while when I was given 3 d after bacterial challenge, a significant protection was afforded. Bactericidal activity in serum increased during the 5 h after I was administered i.p.
The acetyl derivative of I had a high MIC but when inoculated orally in mice decreased the Staph. aureus counts in circulation. This protection occurred only when the schedule of administration started close to the bacterial challenge. Antibiotic activity in vivo may be associated with in vitro effects.     

蜂胶酊对金黄色葡萄球菌性阴道炎疗效观察

目的探讨蜂胶酊对小鼠阴道内致病菌抑制及调理阴道菌群的作用。方法通过感染金黄色葡萄球菌建立小鼠阴道炎模型,用10％蜂胶酊冲洗治疗去除金黄色葡萄球菌在小鼠阴道的定植。倾注培养法（37℃,48h）计数阴道分泌物的细菌总数,镜下观察阴道黏膜炎症程度。结果蜂胶酊治疗组小鼠阴道内细菌的数量明显较对照组数量减少（P〈0．05）,治疗组黏膜炎症的治愈程度显著好于对照组。结论蜂胶酊对小鼠金黄色葡萄球菌性阴道炎有较好的治疗效果。     

Effect of cisplatin on mitochondrial protein, glutathione, and succinate dehydrogenase in Dalton lymphoma-bearing mice

Cisplatin treatment of tumor-bearing mice resulted a significant decrease of protein in the tissues studied (liver, kidney, and Dalton lymphoma) and also in their mitochondrial fractions. As compared to respective tissues, the protein decrease was noted to be more conspicuous in their mitochondrial fractions. Similarly, mitochondrial glutathione also decreased significantly in the tissues. However, succinate dehydrogenase activity was selectively decreased in the kidney and Dalton lymphoma cells, whereas in liver it remained almost unchanged. An increase in serum urea concentration and kidney mitochondrial lipid peroxidation was also observed after cisplatin treatment. It is suggested that the cisplatin-induced biochemical changes in mitochondria involving mitochondrial protein, glutathione, and succinate dehydrogenase could be the important potent cellular sites contributing to toxicity/cytotoxicity after cisplatin treatment. This revised version was published online in July 2006 with corrections to the Cover Date.     

Effect of SH-reagents on aldehyde dehydrogenase activity of the rat liver

SH-reagents: tetraethylthiuram disulphide (TETD), 5,5'-dithiobisnitrobenzoic acid (DTNB), p-chloromercurybenzoate (p-ChMB), N-ethylmaleimide (NEM) were studied for their effect on the aldehyde dehydrogenase activity of mitochondrion (isoenzymes I and II) and microsome (isoenzyme II) fractions of the rat liver. TETD is established to inhibit isoenzyme I and isoenzyme II activity of mitochondrial aldehyde dehydrogenase by 100 and 50%, respectively, and the microsomal enzyme activity by 20%. DTNB and NEM inhibit 30-50% of the activity in two isoforms of mitochondrial aldehyde dehydrogenase having no effect on the enzymic activity in microsomes; p-ChMB inhibits completely the activity of the enzyme under study both in the mitochondrial and microsomal fractions. A conclusion is drawn that SH-groups are very essential for manifestation of the catalytic activity in the NAD+-dependent aldehyde dehydrogenase from mitochondrial and microsomal fractions.     

Effect of the cell components of Staphylococcus aureus on the functional activity of hemopoietic cells in mice

The data on the stimulating action of S. aureus cells, strains B-243, 2287, Wood-46, Cowan I, as well as cell-wall peptidoglycan, on the formation of endogenous colonies in the spleen of sublethally irradiated mice are presented. Teichoic acid, S. aureus ribosomal and cytoplasmic antigens produced no such effect. Whole S. aureus cells and their components were incapable of activating transitory colonies in the spleen of sublethally irradiated mice. After immunization with cell walls, peptidoglycan and protein A the mice showed a rise in the absolute and relative content of blood-forming stem cells in the marrow and the spleen. Killed S. aureus cells increased the relative content of blood-forming stem cells in the marrow, while in the spleen a rise in both absolute and relative content of such cells occurred, which was detected in the exocolonization test.     

Effect of corticotropin on the dehydrogenase activity of cells and tissues

The authors studied the effect of native ACTH on dehydrogenase activity of isolated strips of rat diaphragm and suspension of E. coli cells, serotype O III:B4, grown on beef extract agar in a medium with different dehydrogenation substrates. ACTH activated dehydrogenase of rat diaphragm in a medium containing pyruvate, alpha-ketoglutarate, malate, beta-hydroxybutyrate, D-aspartic acid and did not alter it in a medium containing succinate. In contradistinction to rat diaphragm, ACTH activated dehydrogenase of E. coli cells whatever the substrates used (oxaloacetate, isocitrate, alpha-ketoglutarate, succinate, fumarate, malate, pyruvate, lactate, beta-hydroxybutyrate, glucose, D-aspartic acid. Synacthen (ACTH1-24) exerted a similar effect. It is suggested that the effects of ACTH are mediated via its influence on adenylate cyclase in the absence of receptors.     

Polarized electric field effects on the regulation of succinate dehydrogenase activity in amphibian muscle and liver: kinetic study

Electropolarity treatment (0.8 V/DC/Cm) was given to the gastrocnemius muscle of Bufo melanostictus every day for 5 min. for 5 days, and kinetic study of succinate dehydrogenase (SDH) in muscle and liver was conducted with different effectors - sodium malonate, ethylene diamine tetra acetic acid (EDTA), calcium chloride (CACl2) and sodium citrate. Of the four modulators tested, the malonate and EDTA inhibited while sodium citrate and CACl2 activated the enzyme. The significance of the modulation in SDH activity to different extents was discussed.