tetracycline and zinc-chloride

The emergence of livestock-associated (LA)-methicillin-resistant

Topics: Abattoirs; Animals; Anti-Bacterial Agents; Chlorides; Farmers; Farms; Methicillin; Methicillin Resistance; Methicillin-Resistant Staphylococcus aureus; Multilocus Sequence Typing; Prevalence; Republic of Korea; Staphylococcal Infections; Swine; Swine Diseases; Tetracycline; Zinc Compounds

Adsorption and desorption behaviors of tetracycline hydrochloride by activated carbon-based adsorbents derived from sugar cane bagasse modified with ZnCl

Topics: Adsorption; Cellulose; Charcoal; Chlorides; Hydrogen Bonding; Molecular Structure; Saccharum; Tetracycline; Zinc Compounds

Activated carbon (TAC) prepared under optimized conditions with ZnCl2 activation from a new precursor; tomato industrial processing waste (TW), was applied as an adsorbent to remove tetracycline (TC) from aqueous solution. The factors (TAC dosage, initial TC concentration, contact time, ionic strength and solution temperature) affecting the adsorption process were examined at natural pH (5.7) of TAC-TC system in aqueous solution. Kinetic data was found to be best complied by the pseudo-second order model. The isotherm analysis indicated that the equilibrium data could be represented by the Langmuir model. The maximum adsorption capacity was identified as 500.0mgg(-1) at 308K.

Topics: Adsorption; Anti-Bacterial Agents; Carbon; Chlorides; Hydrogen-Ion Concentration; Industrial Waste; Kinetics; Solanum lycopersicum; Solutions; Temperature; Tetracycline; Waste Disposal, Fluid; Water Pollutants, Chemical; Water Purification; Zinc Compounds

In this study, a new zinc chloride (ZnCl

Topics: Adsorption; Anti-Bacterial Agents; Charcoal; Chlorides; Costs and Cost Analysis; Kinetics; Solutions; Tetracycline; Water Pollutants, Chemical; Water Purification; X-Ray Diffraction; Zinc Compounds

To investigate the mechanism of action of a series of potential combination therapies for use against Helicobacter pylori.. The effects of certain anti-ulcer agents on the antimicrobial activity of antibiotics effective against H. pylori were determined in vitro.. H. pylori was cultured on Skirrow's agar. Amoxycillin, clarithromycin, erythromycin and tetracycline were used. The anti-ulcer agents studied comprised aluminum chloride, sofalcone [2'-carboxymethyl 4,4'-bis(3-methyl-2-butenyloxy)chalcone] and zinc chloride. Urease activity was measured by the urease-indophenol method. The minimum inhibitory concentration was determined by a plating method, with H. pylori streaked on plates containing various concentrations of the antibiotics plus sublethal doses of the anti-ulcer agents.. This in vitro study showed that sofalcone had a direct antibacterial effect and, in addition, inhibited the adhesive property of H. pylori. It did not inhibit the antimicrobial activity of the antibiotics amoxycillin, clarithromycin, erythromycin or tetracycline against H. pylori. The metal ions had inhibitory effects on the antimicrobial activity of amoxycillin, erythromycin and tetracycline, but not on that of clarithromycin.. This study suggests that sofalcone is a suitable candidate for combination therapy.

Topics: Aluminum Chloride; Aluminum Compounds; Amoxicillin; Anti-Bacterial Agents; Anti-Ulcer Agents; Chalcone; Chalcones; Chlorides; Clarithromycin; Drug Interactions; Drug Therapy, Combination; Erythromycin; Helicobacter Infections; Helicobacter pylori; Humans; Microbial Sensitivity Tests; Tetracycline; Zinc Compounds

We inserted the Tn10 tetracycline resistance determinant (tet) into the multicopy plasmid pACYC177, and we examined the phenotype of Escherichia coli K-12 strains harboring these plasmids. In agreement with others, we find that Tn10 tet exhibits a negative gene dosage effect. Strains carrying multicopy Tn10 tet plasmids are 4- to 12-fold less resistant to tetracycline than are strains with a single copy of Tn10 in the bacterial chromosome. In addition, we find that multicopy tet strains are 30- to 100-fold less resistant to the tetracycline derivative 5a,6-anhydrotetracycline than are single-copy tet strains. Multicopy tet strains are, in fact, 10- to 25-fold more sensitive to anhydrotetracycline than are strains that lack tet altogether. The hypersensitivity of multi-copy strains to anhydrotetracycline is correlated with the effectiveness of anhydrotetracycline as an inducer of tet gene expression, rather than its effectiveness as an inhibitor of protein synthesis. Anhydrotetracycline is 50- to 100-fold more effective than tetracycline as an inducer of tetracycline resistance and as an inducer of beta-galactosidase in strains that harbor tet-lac gene fusions. In contrast, anhydrotetracycline appears to be two- to fourfold less effective than tetracycline as an inhibitor of protein synthesis. Both anhydrotetracycline and tetracycline induce synthesis of tet polypeptides in minicells harboring multicopy tet plasmids. Differences between E. coli K-12 backgrounds influence the tetracycline and anhydrotetracycline sensitivity of multicopy strains; ZnCl2 enhances the tetracycline and anhydrotetracycline sensitivity of these strains two- to threefold. We propose that the overexpression of one or more Tn10 tet gene products inhibits the growth of multicopy tet strains and accounts for their relative sensitivity to inducers of tet gene expression.

Topics: Bacterial Proteins; beta-Galactosidase; Chlorides; DNA Transposable Elements; Drug Resistance, Microbial; Escherichia coli; Gene Expression Regulation; Genes, Bacterial; Plasmids; Tetracycline; Tetracyclines; Zinc; Zinc Compounds