sodium-dodecyl-sulfate and Pseudomonas-Infections

The aim of this study was to characterise metallo-β-lactamase (MBL)-harbouring plasmids, their change in copy number in respect to different antibiotic pressure, and the efficiency of different curing agents in eliminating these resistance plasmids from nosocomial Pseudomonas aeruginosa isolates.. Plasmids were extracted from four isolates harbouring bla. Conjugatively transferable MBL genes (bla. The spread of multidrug resistance plasmids has been noted as a key factor associated with increasing carbapenem resistance. Successful curing of resistance plasmids can reverse the bacterial phenotype back to susceptible. This study revealed that different antibiotic pressure induces a change in copy number of MBL-encoding plasmids. SDS can be successfully used as an eliminating agent for these resistance determinants, although therapeutic application of this agent is not possible due to its high toxicity and mutagenic nature.

Topics: Anti-Bacterial Agents; Aztreonam; beta-Lactamases; Cefotaxime; Cross Infection; DNA Copy Number Variations; Drug Resistance, Multiple, Bacterial; Ertapenem; Gene Expression Regulation, Bacterial; Humans; Imipenem; Meropenem; Microbial Sensitivity Tests; Plasmids; Pseudomonas aeruginosa; Pseudomonas Infections; Sodium Dodecyl Sulfate; Suppuration; Urine

Tumor necrosis factor alpha (TNF-alpha)/cachectin is a monocyte/macrophage-derived cytokine implicated as a proximal mediator of many of the catastrophic host responses to infection or endotoxin. However, circulating levels of TNF-alpha/cachectin have only been episodically detected in hospitalized patients with life-threatening bacterial infections. In the present report, increased quantities of immune-reactive TNF-alpha/cachectin were recovered from the livers of rats 3 days following a lethal burn and infection. Two species of TNF-alpha/cachectin were detected, one of approximately 29 kd and the other 17 kd, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In murine peritoneal macrophages and rat Kupffer cells stimulated in vitro with endotoxin, a 29-kd cell-associated and 17-kd secreted form were also detected. We conclude that the increased appearance in vivo of a 29-kd form of TNF-alpha/cachectin from the livers of lethally burned and infected rats represents a novel cell-associated form of the protein.

Topics: Animals; Blotting, Western; Burns; Electrophoresis, Polyacrylamide Gel; Female; Kupffer Cells; Liver; Macrophages; Male; Mice; Mice, Inbred C57BL; Molecular Weight; Pseudomonas aeruginosa; Pseudomonas Infections; Rats; Rats, Inbred Strains; Sodium Dodecyl Sulfate; Tumor Necrosis Factor-alpha