Non-adherence among women enrolled in a contraceptive vaginal ring use study in Kisumu, Kenya, 2014-2015.

BACKGROUND: Given future potential use of vaginal rings to prevent HIV infection, we examined the association of contraceptive vaginal ring (CVR) non-adherence with user dissatisfaction, tolerability, demographic, and behavioral factors. METHODS: In an open-label single-group study, sexually active women aged 18-34 years using oral or injectable hormonal contraception, conveniently sampled from general population, were assigned to 6-month use of a commercial CVR currently not licensed for use in Kenya. Non-adherence in any CVR cycle completed was assessed from: (1) self-report (not used for at least 1 day), and (2) pharmacy record (failure to timely receive a new CVR or return a used one). Additionally, non-adherence was assessed in a subset of participants by residual progestin and estrogen levels measured in returned CVRs. RESULTS: Of 202 participants who underwent CVR insertion by a study clinician, 142 completed all 6 visits, 172 responded to questions about ring use, and 43 provided used CVRs from months 1, 3, and 6 for residual hormone analysis. Non-adherence was 14.0% (24/172) by self-report and 54.5% (110/202) by pharmacy record. Non-adherence by pharmacy record was significantly reduced among women with a salary-based income (prevalence ratio (PR) 0.71, 95% confidence interval (CI) (0.55-0.91)] compared to women with income not salary-based or no income. Participants dissatisfied with CVR on ≥4 aspects (ambiguity of instructions, inconvenience of use, sensation, sexual discomfort, etc.) were more likely to report non-adherence (PR 2.69, 95% CI=(1.31-5.52)] compared to those dissatisfied with ≤3 aspects. Non-adherence by residual hormone levels was identified in 46.5% (20/43) participants. Over time, this subset of participants showed increasing non-adherence (P=0.004). We found lack of agreement among the various measures of non-adherence. CONCLUSIONS: Economic empowerment interventions, especially those emphasizing partner-independent income options, and expanded education on CVR features may alleviate non-adherence. Addressing CVR dissatisfaction preemptively may also help mitigate non-adherence.

Rapid detection and differentiation of antibodies to HIV-1 and HIV-2 using multivalent antigens and magnetic immunochromatography testing.

A simplified lateral-flow assay for the detection of antibodies to HIV using magnetic-bead conjugates and multibranched peptides from both HIV-1 and HIV-2 was developed. Magnetic immunochromatography testing (MICT) uses a standard lateral-flow platform that incorporates magnetic-bead conjugates for quantitative measurement of the magnetic field distortion associated with the bound magnetic conjugate (reported as adjusted relative magnetic units [MAR]). The results of the optimized MICT assay were compared to standard enzyme immunoassay (EIA) and Western blotting (WB) results using a blinded 649-member panel of specimens from the United States, Cameroon, and West Africa. The panel was comprised of samples from individuals infected with various HIV-1 subtypes (n = 234) or HIV-2 (n = 65) and HIV-seronegative specimens (n = 350). Additionally, 13 HIV-1 seroconversion panels (total specimens = 85), a worldwide panel containing seven of the major circulating HIV-1 subtypes (n = 18), an HIV-2 panel, an HIV-1/HIV-2 mixed panel, and 100 prospective specimens were tested with completely concordant results. Assay reproducibility (observed MAR) for both intra- and interrun testing was excellent, with coefficients of variation of <12%. MICT can provide a rapid, low-cost method of determining HIV antibody status requiring no subjective interpretations.

Facilitating chromophore formation of engineered Ca(2+) binding green fluorescent proteins.

Green fluorescent protein (GFP) containing a self-coded chromophore has been applied in protein trafficking and folding, gene expression, and as sensors in living cells. While the "cycle3" mutation denoted as C3 mutation (F99S/M153T/V163A) offers the ability to increase GFP fluorescence at 37 degrees C, it is not clear whether such mutations will also be able to assist the folding and formation of the chromophore upon the addition of metal ion binding sites. Here, we investigate in both bacterial and mammalian systems, the effect of C2 (M153T/V163A) and C3 (F99S/M153T/V163A) mutations on the folding of enhanced GFP (EGFP, includes F64L/S65T) and its variants engineered with two types of Ca(2+) binding sites: (1) a designed discontinuous Ca(2+) binding site and (2) a grafted continuous Ca(2+) binding motif. We show that, for the constructed EGFP variants, the C2 mutation is sufficient to facilitate the production of fluorescence in both bacterial and mammalian cells. Further addition of the mutation F99S decreases the folding efficiency of these variants although a similar effect is not detectable for EGFP, likely due to the already greatly enhanced mutation F64L/S65T from the original GFP, which hastens the chromophore formation. The extinction coefficient and quantum yield of purified proteins of each construct were also examined to compare the effects of both C2 and C3 mutations on protein spectroscopic properties. Our quantitative analyses of the effect of C2 and C3 mutations on the folding and formation of GFP chromophore that undergoes different folding trajectories in bacterial versus mammalian cells provide insights into the development of fluorescent protein-based analytical sensors.