Pseudomonas aeruginosa in vitro phenotypes distinguish cystic fibrosis infection stages and outcomes.

Rationale: Pseudomonas aeruginosa undergoes phenotypic changes during cystic fibrosis (CF) lung infection. Although mucoidy is traditionally associated with transition to chronic infection, we hypothesized that additional in vitro phenotypes correlate with this transition and contribute to disease.

Objectives: To characterize the relationships between in vitro P.

Pseudomonas aeruginosa phenotypes associated with eradication failure in children with cystic fibrosis.

Background: Pseudomonas aeruginosa is a key respiratory pathogen in people with cystic fibrosis (CF). Due to its association with lung disease progression, initial detection of P. aeruginosa in CF respiratory cultures usually results in antibiotic treatment with the goal of eradication.

Staphylococcus aureus small-colony variants are independently associated with worse lung disease in children with cystic fibrosis.

Background: Cystic fibrosis (CF) lung disease is associated with diverse bacteria chronically infecting the airways. Slow-growing, antibiotic-resistant mutants of Staphylococcus aureus known as small-colony variants (SCVs) have been isolated from respiratory secretions from European adults and children with CF lung disease using specific but infrequently used culture techniques. Staphylococcus aureus SCVs can be selected either by exposure to specific antibiotics or by growth with another CF pathogen, Pseudomonas aeruginosa.

Nutrient availability as a mechanism for selection of antibiotic tolerant Pseudomonas aeruginosa within the CF airway.

Microbes are subjected to selective pressures during chronic infections of host tissues. Pseudomonas aeruginosa isolates with inactivating mutations in the transcriptional regulator LasR are frequently selected within the airways of people with cystic fibrosis (CF), and infection with these isolates has been associated with poorer lung function outcomes. The mechanisms underlying selection for lasR mutation are unknown but have been postulated to involve the abundance of specific nutrients within CF airway secretions.

Pseudomonas aeruginosa lasR mutants are associated with cystic fibrosis lung disease progression.

Background: Pseudomonas aeruginosa with mutations in the transcriptional regulator LasR chronically infect the airways of people with cystic fibrosis (CF), yet the prevalence and clinical implications of lasR mutant infection are unknown.

Methods: In an exploratory study, we screened 166 P. aeruginosa isolates from 58 CF patients for LasR inactivation and mucoidy, and compared clinical characteristics among source patients.

Mycoplasma genitalium among young adults in the United States: an emerging sexually transmitted infection.

Objectives: We sought to determine the prevalence of and risk factors associated with Mycoplasma genitalium infection in a nationally representative sample of young adults in the United States.

Methods: Urine specimens from 1714 women and 1218 men who participated in Wave III of the National Longitudinal Study of Adolescent Health (N=14322) were tested for M genitalium. Poststratification sampling weights were used to generate nationally representative estimates.

Periodontitis vaccine decreases local prostaglandin E2 levels in a primate model.

Interleukin-1beta, tumor necrosis factor alpha, prostaglandin E2 (PGE2), and Porphyromonas gingivalis-specific immunoglobulin G levels in gingival crevicular fluid were measured in primates immunized with a P. gingivalis vaccine followed by ligature-induced periodontitis. Only PGE2 levels were dramatically suppressed (P < 0.