Spermicidal activity of extract from Cestrum parqui.

OBJECTIVE: The leaf extract of Cestrum parqui was examined for its effects on sperm motility in vitro. METHODS: Washed sperm were prepared by discontinuous buoyant density gradient centrifugation and incubated with varying concentrations of extract from C. parqui (40-250 microg/mL) at 37 degrees C and 5% CO(2). Sperm motility and viability were assessed at different intervals ranging from 5 to 240 min. Morphological changes in human ejaculated spermatozoa after exposure to the extract were evaluated under transmission electron microscope. RESULTS: A dose- and time-dependent effect of this extract on sperm motility and viability was observed. The maximal spermicidal effect was observed with a 250-microg/mL dose of the extract. Transmission electron microscope revealed a significant damage to sperm membrane in both head and acrosomal membranes, notable swelling and disruption. CONCLUSION: The present study indicates that this natural extract has potential spermicidal effect in vitro.

Inhibition of Neisseria gonorrhoeae genital tract infection by leading-candidate topical microbicides in a mouse model.

The development of effective vaginal microbicides is paramount in the fight against the spread of sexually transmitted infections. Preclinical testing of candidate microbicides for the prevention of gonorrhea has been seriously hindered by the lack of an animal model. We assessed the efficacy of 7 promising formulated agents--CarraGuard, Ushercell, [poly]sodium 4-styrene sulfonate (T-PSS), PRO 2000, ACIDFORM, cellulose acetate phthalate (CAP), and BufferGel--by use of a mouse model of Neisseria gonorrhoeae genital tract infection. Mice received test agent, relevant placebo, or no treatment, followed by intravaginal N. gonorrhoeae challenge. N. gonorrhoeae colonization was tested by vaginal culture. CarraGuard, Ushercell, and T-PSS demonstrated significant protection, compared with control agents and no treatment. PRO 2000, ACIDFORM, and CAP showed significant protection, compared with no treatment but not compared with respective control agents. Mice that received BufferGel were provided significant protection, compared with untreated control mice; no placebo was tested. The findings of the present study suggest that topical agents may effectively reduce N. gonorrhoeae infection and that further evaluation is warranted.

Considerations and development of topical microbicides to inhibit the sexual transmission of HIV.

The increased incidence of HIV/AIDS disease in women aged 15 - 49 years has identified the urgent need for a female-controlled, efficacious and safe vaginal topical microbicide. To meet this challenge, new topical microbicide candidates consisting of molecules or formulations that modify the genital environment (BufferGel, engineered Lactobacillus, over-the-counter lubricants), surfactants (C31D/Savvy, sodium dodecyl sulfate, sodium lauryl sulfate), polyanionic polymers (PRO 2000, beta-cyclodextrin, Carraguard, CAP, D2S, SPL-7013), proteins (cyanovirin-N, monoclonal antibodies, thromspondin-1 peptides, Pokeweed antiviral protein and others), reverse transcription inhibitors (PMPA [Tenofovir ]), UC-781, SJ-3366, DABO and thiourea) and other molecules (NCp7-specific virucides, chemokine receptor agonists/antagonists, WHI-05 and WHI-07) are currently being investigated for activity, safety and efficacy. This review will assess the development of these molecules in the context of cervicovaginal defences and the clinical failure of nonoxynol-9.

Tests of Buffergel for contraception and prevention of sexually transmitted diseases in animal models.

BACKGROUND: BufferGel is a novel spermicidal and microbicidal gel formulated to maintain the natural protective acidity of the vagina by acidifying semen, which otherwise alkalinizes the vagina. GOAL: To test the efficacy of BufferGel for preventing sexually transmitted infections and pregnancy in animal models. STUDY DESIGN: Animals were challenged with pathogens or sperm after pretreatment with both test and control agents, or after no pretreatment, then evaluated for infection or pregnancy using standard methods. RESULTS: BufferGel provided significant contraceptive efficacy in the rabbit, and significant protection against vaginal and rectal transmission of herpes simplex virus type 2 (HSV-2) in the mouse, vaginal transmission of Chlamydia trachomatis in the mouse, and skin transmission of cottontail rabbit papillomavirus in the rabbit. It did not protect against vaginal transmission of Neisseria gonorrhoeae in the mouse. CONCLUSIONS: The protective efficacy of BufferGel in five of the six animal models suggests that this microbicide warrants clinical evaluation for both contraception and disease prevention.

Choice of female-controlled barrier methods among young women and their male sexual partners.

CONTEXT: Little is known about the factors associated with the choice of female-controlled, over-the-counter barrier contraceptive methods among women and their male sexual partners. METHODS: Predictors of method choice were assessed following an educational presentation on contraceptive use and risk reduction among 510 sexually active females aged 15-30 who were recruited in the San Francisco Bay Area. In addition, the primary partners of 160 of these women participated in the survey RESULTS: Twenty-two percent of women who enrolled in the study alone, 25% of those who enrolled with their main partner and 18% of these male partners chose female-controlled, over-the-counter barrier methods alone. The strongest predictor of this choice was current use of a hormonal contraceptive both for women who participated in the study on their own (odds ratio, 2.1) and for those who enrolled their partner in the study (odds ratio, 6.3). Female-controlled methods were also chosen significantly more often by teenagers than by older women; for example, among those who enrolled with a male partner, the odds ratio for selection of a female-controlled barrier method by women younger than 18 was 6.0. Among women who enrolled without a partner, those who had had multiple partners in the previous six months and those who were current users of male condoms were less likely to choose female-controlled methods (odds ratios, 0.7 and 0.5, respectively). CONCLUSIONS: Although the majority of participants did not choose female-controlled, over-the-counter barrier methods without also choosing male condoms, such female-controlled methods appear to offer an acceptable alternative for prevention of sexually transmitted infections. They may be a particularly attractive option for individuals using hormonal contraceptives and for teenage women.