Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PSEUDOMONAS INFECTIONS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 703 records · Page 39Linked to original sources

Natural antibodies in Pseudomonas aeruginosa infections.

Studying 347 sera of 49 patients suffering from Pseudomonas aeruginosa infection the mean titre value (MTV) calculated from the exponent of the binary logarithm of natural antibody (NA) titres, was found suitable to characterize the humoral immune status. As long as the organism is in equilibrium with the infection, the NA level rises. In septic shock, before death or at the development of a massive infection, the NA titre decreases rapidly. The decrease may be due partly to the permeability increasing effect of endotoxin and antigen-antibody reactions exerted on the capillaries. Consequently, in the most severe phase of sepsis, when bacteria enter the circulation less NA is available to fight against them. This might be a cause of the still very high lethality of septic shock due to Gram-negative bacteria. Finally, when applying the MTV one always has to consider that despite its advantages it gives less information than the Backhausz immunogram.

Antibodies↗

Influence of gender and interleukin-10 deficiency on the inflammatory response during lung infection with Pseudomonas aeruginosa in mice.

Cystic fibrosis females have a worse prognosis compared to male patients. Furthermore, cystic fibrosis patients infected with Pseudomonas aeruginosa have been shown to have dysregulated cytokine profiles, as higher levels of tumour necrosis factor alpha (TNF-alpha), interleukin (IL)-8, and lower levels of IL-10 are found in the bronchoalveolar lavage fluid compared to healthy controls. The present study was aimed at investigating the importance of gender and IL-10 in the susceptibility of C57BL/6 mice to pulmonary infection with Pseudomonas aeruginosa. We found that wildtype females were more susceptible than males to infection, as we observed greater weight loss, higher bacterial load, and inflammatory mediators in their lungs. IL-10 knockout mice, both females and males, had higher levels of TNF-alpha in the lungs compared to wildtype mice and maintained higher levels of polymorphonuclear cells and lower levels of macrophages for a longer period of time. Our results demonstrate that the number of bacteria recovered from the lungs of IL-10 knockout male mice was significantly higher than that observed in their wildtype male counterparts and we show that neutralization of IL-10 in infected female mice for a prolonged period of time leads to increased susceptibility to infection. Results reported in this study clearly demonstrate that females, both wildtype and IL-10 knockout mice are more susceptible to Pseudomonas aeruginosa infection than males, and that they mount a stronger inflammatory response in the lungs.

Animals↗

Zinc tape treatment of burns infected by Pseudomonas aeruginosa: an experimental study on guinea pigs.

Third-degree burns on guinea pigs were infected with Pseudomonas aeruginosa. The wounds were treated with a zinc tape, a gauze sponge, or a plastic foil. In tissue specimens from the wounds, less growth of Pseudomonas was found in zinc tape treated wounds than in gauze- or plastic foil treated wounds. In vitro it was found that zinc oxide possesses an antibacterial effect on Pseudomonas aeruginosa, Staphylococcus aureus and Streptococcus pyogenes.

Animals↗

Pulmonary retention of free and liposome-encapsulated tobramycin after intratracheal administration in uninfected rats and rats infected with Pseudomonas aeruginosa.

The pulmonary residence time of free and liposome-encapsulated tobramycin was studied with uninfected rats and rats infected with Pseudomonas aeruginosa. Chronic infection in lungs was established by intratracheal administration of 10(8) CFU of P. aeruginosa PA 508 prepared in agar beads. After 3 days, a single dose (300 micrograms) of free or liposome-encapsulated tobramycin was given intratracheally to both infected and uninfected rats. At various time intervals (0.25 to 16 h) after drug instillations, the remaining tobramycin was evaluated in blood, lungs, and kidneys by a microbiological assay. Intratracheal instillation of liposome-encapsulated tobramycin resulted in high and sustained levels of tobramycin in lungs of uninfected and infected rats over the 16-h period studied; however, the tobramycin levels were two times higher in uninfected rats. There was no tobramycin detected in the blood or kidneys from these animals. In contrast, the intratracheally instilled free tobramycin was cleared within 3 and 1 h from the lungs of uninfected and infected animals, respectively. These data suggest that the encapsulation of tobramycin in liposomes can result in a significant increase of its residence time within lungs. This study also shows that pulmonary infection was associated with a lowering of tobramycin levels in lungs.

Animals↗

Effects of the beige mutation on respiratory tract infection with Pseudomonas aeruginosa in mice.

The role of neutrophil proteinases in the pathogenesis of respiratory tract infections with Pseudomonas aeruginosa was evaluated by studying the course of murine respiratory tract infection with a clinical isolate of P. aeruginosa mucoid strain developed by the agarose beads method in C57BL/6J(bg/bg) mice (beige mice). Neutrophils of beige mice are known to have defects in elastase and cathepsin G, but to have normal ability to produce reactive oxygen species. Contrary to the reported high susceptibility of beige mice to bacterial infections, we found that intratracheal inoculation of approximately 10(5) colony-forming units (CFU) of P. aeruginosa enmeshed in agarose beads resulted in lower mortality (0/16 versus 16/16, p < .01), fewer CFU counts in the lungs on day 5 (p < .05), and fewer elastolytic lung tissue injuries in beige mice compared with C57BL/6(+/+) mice. In vitro bactericidal study, however, revealed that beige neutrophils killed fewer bacteria than those of C57BL/6(+/+) mice (p < .05). Neutrophil elastase activities in the supernatants of pulmonary lavaged fluids measured using methoxysuccinyl-alanyl-alanyl-prolyl-valine-4-methylcoumar-7-amide were lower (p < .05) in beige mice than those in the normal littermates, whereas neutrophil recruitment into the airways and production of superoxide anion measured as the superoxide dismutase inhibitable rate of cytochrome c reduction were not impaired. These results suggest that neutrophil proteinases play a key role in tissue injuries in the respiratory tract infection with P. aeruginosa.

Animals↗

Pseudomonas aeruginosa infections in the neonatal intensive care unit.

Pseudomonas aeruginosa is a highly adaptable gram-negative bacillus with the ability to cause serious disease in vulnerable populations. This article reviews the relevant epidemiology of this pathogen in the hospital setting with particular attention to the neonatal unit. Issues related to reservoirs of the organism with special consideration of the hands of staff are also addressed. Virulence factors and pathogenic mechanisms are highlighted as well as the important role of antimicrobial resistance patterns. Finally, there is a discussion of the clinical syndromes found in neonates and the appropriate antibiotic usage strategies for effective treatment of this pathogen of continuing importance.

Cross Infection↗

Pseudomonas aeruginosa infections associated with use of contaminated medicaments.

Pseudomonas aeruginosa was recovered from three hospital-prepared medicaments being used on the wards. Sixty-six patients were studied to observe the effect of using these contaminated medicaments. Psaeruginosa was recovered from 29 patients; in five the strains recovered bore a close resemblance to strains previously isolated from the contaminated medicaments.

Cosmetics↗

Drosophila as a model host for Pseudomonas aeruginosa infection.

Using the fruit fly Drosophila melanogaster as model host, we have identified mutants of the bacterium Pseudomonas aeruginosa with reduced virulence. Strikingly, all strains strongly impaired in fly killing also lacked twitching motility; most such strains had a mutation in pilGHIJKL chpABCDE, a gene cluster known to be required for twitching motility and potentially encoding a signal transduction system. The pil chp genes appear to control the expression of additional virulence factors, however, since the wild-type fly-killing phenotype of a subset of mutants isolated on the basis of their compact colony morphology indicated that twitching motility itself was not required for full virulence in the fly.

Animals↗

Role of elastase as a virulence factor in experimental Pseudomonas aeruginosa infection in mice.

The role of elastase and alkaline protease in the pathogenesis of fatal infections caused by Pseudomonas aeruginosa was determined in mice treated with calcium chloride. Mortality increased significantly when solutions containing elastase were injected together with non-lethal inocula of strain PA 103, which does not produce proteolytic enzyme. In contrast, solutions containing alkaline protease did not increase mortality. In mice injected intramuscularly with strain PA 103 and calcium chloride, the organisms grew rapidly in the injected muscle but not in the liver. However, when elastase was injected together with strain PA 103 and calcium chloride, viable bacteria were also found in the liver. Moreover, the survival rate of mice challenged with elastase-producing strain 5 and calcium chloride was enhanced, and colonization of the liver prevented, by immunization with elastase toxoid. These results suggest that elastase contributes to the invasiveness of the organism.

Animals↗