Search

Preexposure prophylaxis (PrEP) and treatment as prevention (TasP) involve the use of antiretroviral (ARV) drugs by human immunodeficiency virus (HIV)-negative and -positive individuals to reduce HIV acquisition and transmission, respectively. Clinical science has delivered a consistently high effect size for TasP and a range from 0%-73% reduction in incidence across placebo-controlled PrEP trials. However, the quality of evidence for PrEP compares favorably with evidence for postexposure prophylaxis (PEP). It is clear from treatment programs and PrEP trials that daily adherence presents challenges to a large proportion of the population. Although there are factors associated with inconsistent use (ie, younger age), they do not assist clinicians at the point of care. There are additional provider concerns about PrEP (covering cost of drug and delivery, undermining condom promotion, and facilitating resistant strains) that have delayed widespread acceptance. These issues need to be addressed in order to realize the full public health potential of antiretrovirals., (© The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America.)

Relaxin, a uterine relaxant secreted by the corpus luteum, was able to elevate cAMP concentrations in the presence of 1-methyl-3-isobutyl xanthine (MIX) (0.1 mM) or forskolin (0.4 microM) in a time- and dose-dependent manner in rat myometrial cells in culture but not in stromal cells. The optimal culture conditions for the cAMP response were determined to be an initial plating density of 1-1.5 X 10(6) cells/ml (3 ml/35-mm dish) and a 2-day culture period. In the presence of MIX, the time course of cAMP elevation in response to relaxin exhibited a lag phase of more than 5 min before cAMP concentrations rose significantly. However, in the presence of forskolin, relaxin elevated cAMP within 1 min. The concentration-response relationships were almost identical in the presence of MIX or forskolin. Isoproterenol was able to increase cAMP concentrations in myometrial cultures in both the absence and presence of MIX and to elevate cAMP levels rapidly within 1 min. These data suggest that cAMP could play some role in the initiation of uterine relaxation mediated by relaxin.