A toroid model for in vitro investigations of toxic shock syndrome toxin-1 production.

Human behaviours and consumer products may affect vaginal microbial ecology, thereby influencing women's health. Relevant experimentation systems are needed to understand such possible links. Here, we describe the development of a practical semi-solid in vitro model to assess the effects of interactions between vaginal environment and the presence of tampons, on bacterial communities, including the production of toxic shock syndrome toxin-1 (TSST-1) by Staphylococcus aureus.

Antibodies to a surface-exposed, N-terminal domain of aggregation substance are not protective in the rabbit model of Enterococcus faecalis infective endocarditis.

The aggregation substance (AS) surface protein from Enterococcus faecalis has been implicated as an important virulence factor for the development of infective endocarditis. To evaluate the role of antibodies specific for Asc10 (the AS protein from the conjugative plasmid pCF10) in protective immunity to infective endocarditis, an N-terminal region of Asc10 lacking the signal peptide and predicted to be surface exposed (amino acids 44 to 331; AS(44-331)) was cloned with a C-terminal histidine tag translational fusion and expressed from Escherichia coli. N-terminal amino acid sequencing of the purified protein revealed the correct sequence, and rabbit polyclonal antisera raised against AS(44-331) reacted specifically to Asc10 expressed from E. faecalis OG1SSp, but not to other proteins as judged by Western blot analysis. Using these antisera, flow cytometry analysis demonstrated that antibodies to AS(44-331) bound to a surface-exposed region of Asc10. Furthermore, antibodies specific for AS(44-331) were opsonic for E. faecalis expressing Asc10 in vitro but not for cells that did not express Asc10. New Zealand White rabbits immunized with AS(44-331) were challenged intravenously with E. faecalis cells constitutively expressing Asc10 in the rabbit model of experimental endocarditis. Highly immune animals did not show significant differences in clearance of organisms from the blood or spleen or in formation of vegetations on the aortic valve, in comparison with nonimmune animals. Although in vivo expression of Asc10 was demonstrated by immunohistochemistry, these experiments provide evidence that immunity to Asc10 does not play a role in protection from experimental infective endocarditis due to E. faecalis and may have important implications for the development of immunological approaches to combat enterococcal endocarditis.

Development of streptococcal pyrogenic exotoxin C vaccine toxoids that are protective in the rabbit model of toxic shock syndrome.

Streptococcal pyrogenic exotoxin C (SPE C) is a superantigen produced by many strains of Streptococcus pyogenes that (along with streptococcal pyrogenic exotoxin A) is highly associated with streptococcal toxic shock syndrome (STSS) and other invasive streptococcal diseases. Based on the three-dimensional structure of SPE C, solvent-exposed residues predicted to be important for binding to the TCR or the MHC class II molecule, or important for dimerization, were generated. Based on decreased mitogenic activity of various single-site mutants, the double-site mutant Y15A/N38D and the triple-site mutant Y15A/H35A/N38D were constructed and analyzed for superantigenicity, toxicity (lethality), immunogenicity, and the ability to protect against wild-type SPE C-induced STSS. The Y15A/N38D and Y15A/H35A/N38D mutants were nonmitogenic for rabbit splenocytes and human PBMCs and nonlethal in two rabbit models of STSS, yet both mutants were highly immunogenic. Animals vaccinated with the Y15A/N38D or Y15A/H35A/N38D toxoids were protected from challenge with wild-type SPE C. Collectively, these data indicate that the Y15A/N38D and Y15A/H35A/N38D mutants may be useful as toxoid vaccine candidates.

Staphylococcal exfoliative toxins cleave alpha- and beta-melanocyte-stimulating hormones.

The staphylococcal exfoliative toxins (ETs) A and B (ETA and ETB) are 27-kDa exotoxins produced by certain strains of Staphylococcus aureus and are the causative agents of staphylococcal scalded-skin syndrome. The crystal structures of the ETs strongly indicate that the proteins are members of the serine protease family of enzymes, although protease activity until now has not yet been conclusively demonstrated. Here, we show that the peptide beta-melanocyte-stimulating hormone (beta-MSH) is cleaved by ETA and that both ETA and ETB are capable of cleaving alpha-MSH. Both toxins exhibit cleavage at specific glutamic acid residues in MSH peptides. Moreover, biologically inactive mutants of ETA were incapable of cleaving beta-MSH.

Comparing the health status of male and female veterans who use VA health care: results from the VA Women's Health Project.

BACKGROUND: In recent years the number of women serving in the military has increased substantially, resulting in more demand for VA services by women veterans. This paper describes the characteristics and health status of women veterans who use VA ambulatory services. METHODS: Respondents in the VA Women's Health Project (n = 719) represent a randomly selected subsample from all women who had an ambulatory visit between July 1, 1994 and June 30, 1995 at a large tertiary care VA facility in the Boston area. Summary statistics on eight dimensions of health status (using the SF-36) for women veterans who use VA ambulatory care are provided. Comparisons are made between women veterans and men veterans who use VA services. RESULTS: Women veterans reported consistently low scores on health status across multiple dimensions, reflecting considerable health needs. Among veterans using VA services, women were younger, better educated, and less likely to be married than male veterans. Women veterans who use VA ambulatory services scored lower on every scale except physical functioning and general health perceptions when compared to male VA users. There were more pronounced differences for women on scales measuring emotional health. CONCLUSIONS: Health status among women veterans is moderate to poor. Important differences in health status are observed between men and women who use VA services which have implications for improving health care to women veterans at VA facilities. These findings strongly indicate that increased mental health services need to be available for women veterans seeking VA health care.

Medical profile of women Veterans Administration outpatients who report a history of sexual assault occurring while in the military.

To profile differences in current physical symptoms and medical conditions among women users of Veterans Administration (VA) health services with and without a self-reported history of sexual assault sustained during military service, we conducted a cross-sectional analysis of a nationally representative, random sample of women veterans using VA outpatient services (n = 3632). A self-administered, mailed survey asked whether women had sustained sexual assault while in the military and requested information about a spectrum of physical symptoms and medical conditions. A history of sexual assault while in the military was reported by 23% of women VA users and was associated with current physical symptoms and medical conditions in every domain assessed. For example, women who reported sexual assault were more likely to indicate that they had a "heart attack" within the past year, even after adjusting for age, hypertension, diabetes, and smoking history (OR 2.3, 95% CI 1.3-4.0). Among women reporting a history of sexual assault while in the military, 26% endorsed > or = 12 of 24 symptoms/conditions, compared with 11% of women with no reported sexual assault while in the military (p < 0.001). Clinicians need to be attuned to the high frequency of sexual assault occurring while in the military reported by women VA users and its associated array of current physical symptoms and medical conditions. Clinicians should consider screening both younger and older patients for a sexual violence history, especially patients with multiple physical symptoms.

Prevalence of depressive and alcohol abuse symptoms among women VA outpatients who report experiencing sexual assault while in the military.

Among a national sample of 3,632 women VA outpatients, we determined self-reported prevalence of sexual assault experienced during military service and compared screening prevalence for current symptoms of depression and alcohol abuse between those who did and did not report this history. Data were obtained by mailed questionnaire. Military-related sexual assault was reported by 23%. Screening prevalence for symptoms of current depression was 3 times higher and for current alcohol abuse was 2 times higher among those who reported experiencing military-related sexual assault. Recent mental health treatment was reported by 50% of those who reported experiencing sexual assault during military service and screened positive for symptoms of depression, and by 40% of those who screened positive for symptoms of alcohol abuse.