Integrating Prevention of Mother-to-Child HIV Transmission Programs to Improve Uptake: A Systematic Review

BACKGROUND: We performed a systematic review to assess the effect of integrated perinatal prevention of mother-to-child transmission of HIV interventions compared to non- or partially integrated services on the uptake in low- and middle-income countries. METHODS: We searched for experimental, quasi-experimental and controlled observational studies in any language from 21 databases and grey literature sources. RESULTS: Out of 28 654 citations retrieved, five studies met our inclusion criteria. A cluster randomized controlled trial reported higher probability of nevirapine uptake at the labor wards implementing HIV testing and structured nevirapine adherence assessment (RRR 1.37, bootstrapped 95% CI, 1.04-1.77). A stepped wedge design study showed marked improvement in antiretroviral therapy (ART) enrolment (44.4% versus 25.3%, p<0.001) and initiation (32.9% versus 14.4%, p<0.001) in integrated care, but the median gestational age of ART initiation (27.1 versus 27.7 weeks, p = 0.4), ART duration (10.8 versus 10.0 weeks, p = 0.3) or 90 days ART retention (87.8% versus 91.3%, p = 0.3) did not differ significantly. A cohort study reported no significant difference either in the ART coverage (55% versus 48% versus 47%, p = 0.29) or eight weeks of ART duration before the delivery (50% versus 42% versus 52%; p = 0.96) between integrated, proximal and distal partially integrated care. Two before and after studies assessed the impact of integration on HIV testing uptake in antenatal care. The first study reported that significantly more women received information on PMTCT (92% versus 77%, p<0.001), were tested (76% versus 62%, p<0.001) and learned their HIV status (66% versus 55%, p<0.001) after integration. The second study also reported significant increase in HIV testing uptake after integration (98.8% versus 52.6%, p<0.001). CONCLUSION: Limited, non-generalizable evidence supports the effectiveness of integrated PMTCT programs. More research measuring coverage and other relevant outcomes is urgently needed to inform the design of services delivering PMTCT programs

Parthenogenesis in insects: the centriole renaissance

Building a new organism usually requires the contribution of two differently shaped haploid cells, the male and female gametes, each providing its genetic material to restore diploidy of the new born zygote. The successful execution of this process requires defined sequential steps that must be completed in space and time. Otherwise, development fails. Relevant among the earlier steps are pronuclear migration and formation of the first mitotic spindle that promote the mixing of parental chromosomes and the formation of the zygotic nucleus. A complex microtubule network ensures the proper execution of these processes. Instrumental to microtubule organization and bipolar spindle assembly is a distinct non-membranous organelle, the centrosome. Centrosome inheritance during fertilization is biparental, since both gametes provide essential components to build a functional centrosome. This model does not explain, however, centrosome formation during parthenogenetic development, a special mode of sexual reproduction in which the unfertilized egg develops without the contribution of the male gamete. Moreover, whereas fertilization is a relevant example in which the cells actively check the presence of only one centrosome, to avoid multipolar spindle formation, the development of parthenogenetic eggs is ensured, at least in insects, by the de novo assembly of multiple centrosomes. Here, we will focus our attention on the assembly of functional centrosomes following fertilization and during parthenogenetic development in insects. Parthenogenetic development in which unfertilized eggs are naturally depleted of centrosomes would provide a useful experimental system to investigate centriole assembly and duplication together with centrosome formation and maturation