Stephen E. Hawes

This cohort study of 182 women attending a sexually transmitted disease clinic evaluated the hypothesis that women colonized by lactobacilli have decreased acquisition of vaginal infections. During a 2-year follow-up, 50 women acquired bacterial vaginosis (BV), 25 acquired symptomatic vulvovaginal candidiasis (YYC), and 7 acquired vaginal trichomoniasis. By multivariate analysis, utilizing Cox proportional hazards modeling with time-dependent covariates, acquisition of BV was independently associated with lack of vaginal H202-producing lactobacilli (hazard ratio [HR] = 4.0, P < .001) or presence of only non–H202-producing lactobacilli (HR = 2.2, P = .02). Acquisition of BV was associated with having a new sex partner (HR = 2.5, P = .004) and with douching for hygiene (HR = 2.1, P = .05). Absence of lactobacilli did not increase acquisition of VVC. Trichomoniasis was associated only with having a new sex partner (HR = 4.7, P = .05). These results support the hypothesis that H202-producing vaginal lactobacilli protect against acquisition of BV but do not protect against VVC or vaginal trichomoniasis.

Lactobacillus acidophilus has been reported to be the predominant vaginal species. Vaginal lactobacilli isolated from 215 sexually active women were identified using whole-chromosomal DNA probes to 20 American Type Culture Collection Lactobacillus strains. Most women were colonized by L. crispatus (32%), followed by L. jensenii (23%), a previously undescribed species designated L. 1086V (15%), L. gasseri (5%), L. fermentum (0.3%), L. oris (0.3%), L. reuteri (0.3%), L. ruminis (0.3%), and L. vaginalis (0.3%). H2O2 was produced by 95% of L. crispatus and 94% of L. jensenii isolates, compared with only 9% of L. 1086V. Colonization by L. crispatus or L. jensenii was positively associated with being white (P<.001), age >/=20 years (P=.05), barrier contraceptive usage (P=.008), and lower frequency of bacterial vaginosis (P<.001) and gonorrhea (P=.03). L. crispatus and L. jensenii, not L. acidophilus, are the most common species of vaginal lactobacilli.

BACKGROUND: In contrast to the wealth of data on human papillomavirus (HPV) infections in women, much less is known about HPV in men. METHODS: Between June 2003 and March 2006, a total of 240 heterosexually active male university students 18-20 years of age were recruited for participation in a cohort study of HPV infection. Genital cell samples were collected, at 4-month intervals, for HPV-DNA analysis by polymerase chain reaction. The subjects maintained a Web-based journal of sexual activity. RESULTS: At 24 months, the cumulative incidence of new infection of any genital HPV type was 62.4% (95% confidence interval [CI], 52.6%-72.2%). Acquisition rates did not differ by genital site (i.e., glans, penile shaft, or scrotum) of initial detection (P=.86). The most commonly detected types were HPV-84 and HPV-16. In multivariate analysis, a report of a new sex partner during the prior 0-4 (hazards ratio [HR], 2.0 [95% CI, 1.3-3.0]) and 5-8 (HR, 1.8 [95% CI, 1.2-2.7]) months and a history of smoking (HR, 1.6 [95% CI, 1.1-2.4]) were associated with an elevated risk of HPV acquisition. CONCLUSION: Genital HPV infection is common and multifocal in young men, and its incidence is higher than that reported for similar cohorts of young women. The high rates of HPV infection in men should be considered when strategies for the prevention of HPV infection in female adolescents and young women are being developed.

PURPOSE: Novel approaches to breast cancer screening are necessary, especially in the developing world where mammography is not feasible. In this study, we explored the hypothesis that blood-based biomarkers have potential for biomarkers for breast cancer. PATIENTS AND METHODS: We first determined the frequency of aberrant methylation of four candidate genes (APC, GSTP1, Rassf1A, and RARbeta2) in primary breast cancer tissues from West African women with predominantly advanced cancers. We used a high-throughput DNA methylation assay (quantitative methylation-specific polymerase chain reaction) to examine plasma from 93 women with breast cancer and 76 controls for the presence of four methylated genes. Samples were randomly divided evenly into training and validation data sets. Cutoff values for gene positivity of the plasma-based assay and the gene panel were determined by receiver operating characteristic curves in the training data set and subsequently evaluated as a screening tool in the validation data set. RESULTS: Methylation of at least one gene resulted in a sensitivity of 62% and a specificity of 87%. Moreover, the assay successfully detected 33% (eight of 24) of early-stage tumors. CONCLUSION: These data suggest that epigenetic markers in plasma may be of interest for detection of breast cancer. Identification of additional breast cancer specific methylated genes with higher prevalence in early stage cancers would improve this approach.

To identify factors that predict sustained colonization by vaginal lactobacilli, microbiologic, behavioral, and demographic data were obtained from 101 nonpregnant women at baseline and at 4 and 8 months. A total of 272 isolates of lactobacilli were identified to the species level by use of whole chromosomal DNA homology to type strains. The predominant lactobacilli were the species Lactobacillus crispatus (38%) and L. jensenii (41%). Of 57 women initially colonized by H(2)O(2)-producing L. crispatus or L. jensenii, 23 (40%) remained colonized over 8 months, compared with 1 (5%) of 21 women colonized by other H(2)O(2)-producing species or by H(2)O(2)-negative strains (P=.01). Frequency of sexual intercourse (> or =1 sex act per week) was associated with loss of colonization with H(2)O(2)-producing lactobacilli (P=.018), as was antibiotic use (P< or =.0001). Other behavioral and demographic characteristics did not predict sustained colonization. The production of H(2)O(2) is closely linked with species and is a predictor for sustained long-term colonization of the vagina.