Influence of Matrix Polarity on the Properties of Ethylene Vinyl Acetate–Carbon Nanofiller Nanocomposites

A series of ethylene vinyl acetate (EVA) nanocomposites using four kinds of EVA with 40, 50, 60, and 70 wt% vinyl acetate (VA) contents and three different carbon-based nanofillers—expanded graphite (EG), multi-walled carbon nanotube (MWCNT), and carbon nanofiber (CNF) have been prepared via solution blending. The influence of the matrix polarity and the nature of nanofillers on the morphology and properties of EVA nanocomposites have been investigated. It is observed that the sample with lowest vinyl acetate content exhibits highest mechanical properties. However, the enhancement in mechanical properties with the incorporation of various nanofillers is the highest for EVA with high VA content. This trend has been followed in both dynamic mechanical properties and thermal conductivity of the nanocomposites. EVA copolymer undergoes a transition from partial to complete amorphousness between 40 and 50 wt% VA content, and this changes the dispersion of the nanofillers. The high VA-containing polymers show more affinity toward fillers due to the large free volume available and allow easy dispersion of nanofillers in the amorphous rubbery phase, as confirmed from the morphological studies. The thermal stability of the nanocomposites is also influenced by the type of nanofiller

Reproductive health and lifestyle factors associated with health-related quality of life among perinatally HIV-infected adolescents in Uganda

Background With increased survival of perinatally HIV - infected adolescents due to antiretroviral therapy (ART), the focus of HIV care has shifted to health-related quality of life (HRQoL) as a measure of disease progression, effects of ART co-morbidity and prognosis. We assessed factors associated with better HRQoL in perinatally HIV -infected adolescents in Uganda by determining the associations between sexual and reproductive health (SRH) or lifestyle experiences on HRQoL. Methods In a cross-sectional study, data on SRH, lifestyle experiences, socio demographic factors, communication with parents on sexuality and satisfaction of SRH services in ART clinics were collected from 614 HIV perinatally infected adolescents aged 10–19 using an interviewer-administered survey questionnaire. HRQoL data were collected using the Medical Outcomes Study HIV Health Survey instrument (MOS-HIV). Factors associated with better HRQoL were analysed using multiple logistic regression. Results The mean age was 16.2 ± 2.1 years, 362 (58.8 %) were females and 210 (34.2 %) were sexually active. Adolescents on ART were twice likely to present with better physical health (AOR = 2.07, 95 % CI: 1.24–3.46) and four times more likely to present with better mental health (AOR = 3.9, 95 % CI: 2.22–6.92) than those who were not on ART. There were no statistically significant associations between SRH (ever had sex, ever been pregnant, condom use, contraceptive use) or life style factors and physical health or mental health. Those with secondary or tertiary education were more likely to present with a better mental health (AOR = 5.3, 95 % CI: 1.86–15.41) compared those who had attained primary or no education. Participants who desired to have a child in future more likely (AOR 1.7, 95 % CI: 1.05–3.00) to present with a better mental health. Lack of communication with guardians on sexuality (AOR = 0.6, 95 % CI: 0.40–0.89), or dissatisfaction with SRH services (AOR 0.34, 95 % CI: 0.18–0.62) were associated with poorer mental health. Conclusion Among perinatally HIV-infected adolescents in Uganda, being on ART was associated with better physical and mental health while lack of communication with guardians on sexuality or dissatisfaction with SRH services was associated with poor mental health. Adolescents with pregnancy intentions were more likely to have a better mental health

RISK FACTORS OF HIV-1 VERTICAL TRANSMISSION (VT) AND THE INFLUENCE OF ANTIRETROVIRAL THERAPY (ART) IN PREGNANCY OUTCOME

In the absence of intervention, the rate of vertical transmission of HIV can range from 15-45%. With the inclusion of antiretroviral drugs during pregnancy and the choice of delivery route this amounts to less than 2%. However ARV use during pregnancy has generated several questions regarding the adverse effects of the gestational and neonatal outcome. This study aims to analyze the risk factors for vertical transmission of HIV-1 seropositive pregnant women living in Rio Grande and the influence of the use of ARVs in pregnancy outcome. Among the 262 pregnant women studied the rate of vertical transmission of HIV was found to be 3.8%. Regarding the VT, there was a lower risk of transmission when antiretroviral drugs were used and prenatal care was conducted at the referral service. However, the use of ART did not influence the outcome of pregnancy. However, initiation of prenatal care after the first trimester had an influence on low birth weight, as well as performance of less than six visits increased the risk of prematurity. Therefore, the risk factors analyzed in this study appear to be related to the realization of inadequate pre-natal and maternal behavior

Human immunodeficiency virus diagnostic testing of infants at clinical sites in North America: 2002-2006

Our objectives were to assess the timing of testing, the types of diagnostic assays used, and the costs associated with the diagnosis of HIV-1 infection among infants born to HIV-1-infected women enrolled in the International Maternal Pediatric Adolescent AIDS Clinical Trials Group Protocol 1025 (P1025). P1025 is a prospective cohort study of HIV-1-infected women and their infants at clinical sites in the United States and Puerto Rico. Enrollment began in 2002 and is ongoing. Follow-up of infants continued for at least 6 months after delivery/birth. The study population for this analysis comprised all live born infants of known HIV-1 infection status, born by December 31, 2006 to enrolled women. Nine hundred eighty-eight infants had 5147 HIV-1 diagnostic test results reported. The median number of HIV-1 diagnostic assays performed per infant was 5 (10th, 90th percentiles: 3, 7), and the greatest number of tests reported per infant was 13. The median ages at the time of the first, second, third, and fourth HIV-1 diagnostic assay were 0.1, 2.3, 7.0, and 17.6 weeks, respectively. Nucleic acid amplification tests (NAATs) represented 86.9% of all diagnostic assays (HIV-1 DNA PCR assays: n = 4082 [79.3%]; other NAATs: n = 389 [7.6%]). The median cost per infant for HIV-1 diagnostic testing was $1168 (10th, 90th percentiles:$762, $1642). Most assays reported for HIV-1-exposed infants at clinical sites in the United States and Puerto Rico were NAATs, but the number of HIV-1 diagnostic assays performed per infant, and the cost associated with HIV-1 diagnostic testing per infant, varied greatly

Missed Opportunities for Prevention of Mother-to-Child Transmission of Human Immunodeficiency Virus

OBJECTIVE:To identify missed opportunities for prevention of mother-to-child transmission of human immunodeficiency virus (HIV). METHODS:Data regarding HIV-infected children born between 2002 and 2009 to HIV-infected women enrolled in the U.S. International Maternal Pediatric Adolescent AIDS Clinical Trials prospective cohort study (protocol P1025) were reviewed. The characteristics of the HIV-infected infants and their mothers and the mothersʼ clinical management are described. RESULTS:Twelve cases of mother-to-child transmission of HIV occurred among 1,857 liveborn neonates, for a prevalence of 0.65 per 100 live births to HIV-infected women (95% confidence interval 0.33–1.13). Four transmissions occurred in utero, three were peripartum transmissions, and the timing of transmission for five neonates was unable to be determined. None were breastfed. Seven women had plasma viral loads greater than 400 copies/mL near delivery. Six women had less than 11 weeks of antiretroviral therapy during pregnancy; three of these women had premature deliveries. One woman received no antiretroviral therapy during pregnancy because she was diagnosed with HIV postpartum. Six had poor to moderate adherence to antiretroviral therapy. Four of the five mothers with viral loads greater than 1,000 copies/mL delivered preterm neonates. There were five women who delivered by cesarean; four were nonelective cesarean deliveries and only one was an elective cesarean delivery for HIV prevention. CONCLUSION:Despite access to high-level care and follow-up, a small proportion of HIV-infected women transmitted the virus to their neonates. This case series provides insight into factors contributing to HIV perinatal transmission and can inform the development of new strategies for prevention of mother-to-child transmission of HIV. CLINICAL TRIAL REGISTRATION:ClinicalTrials.gov, https://clinicaltrials.gov, NCT00028145