Conductivity measurements in silicic acid gels during setting

During the course of extensive investigations of the properties and behavior of silicic acid gels, the study of the conductivity of these substances was begun in the hope that data could be assembled to throw some light on the mechanism of gelation. The experiments to be described are a continuation of the work on conductivity carried out at Union College under the direction of Dr. C. B. Hurd. H. Swanker (1), in 1932, making use of a Wheatstone bridge at 1000 cycles, failed to find any change in conductivity, but R. W. Gurry (2), using refined methods, was able to detect small changes as the gels set. Subsequently the technique of measurement was further improved by R. Slobod (3) in 1935, and R. E. Russel (4) in 1936. Slobod\u27s curves showed a definite increase in conductivity, but his own experiments and those of Russell made those results appear doubtful. Russell, continuing the work of Slobod on the equilibrium phenomena arising, studied the treatment of the electrodes

Estimating age-based antiretroviral therapy costs for HIV-infected children in resource-limited settings based on World Health Organization weight-based dosing recommendations

Background: Pediatric antiretroviral therapy (ART) has been shown to substantially reduce morbidity and mortality in HIV-infected infants and children. To accurately project program costs, analysts need accurate estimations of antiretroviral drug (ARV) costs for children. However, the costing of pediatric antiretroviral therapy is complicated by weight-based dosing recommendations which change as children grow. Methods: We developed a step-by-step methodology for estimating the cost of pediatric ARV regimens for children ages 0–13 years old. The costing approach incorporates weight-based dosing recommendations to provide estimated ARV doses throughout childhood development. Published unit drug costs are then used to calculate average monthly drug costs. We compared our derived monthly ARV costs to published estimates to assess the accuracy of our methodology. Results: The estimates of monthly ARV costs are provided for six commonly used first-line pediatric ARV regimens, considering three possible care scenarios. The costs derived in our analysis for children were fairly comparable to or slightly higher than available published ARV drug or regimen estimates. Conclusions: The methodology described here can be used to provide an accurate estimation of pediatric ARV regimen costs for cost-effectiveness analysts to project the optimum packages of care for HIV-infected children, as well as for program administrators and budget analysts who wish to assess the feasibility of increasing pediatric ART availability in constrained budget environments

Development of a Surgical Workforce Access Team (SWAT) in the Battle Against COVID-19

In response to the COVID-19 pandemic, our vascular surgery division has implemented a 24/7 vascular access team to provide line placement services throughout our medical center. We believe this model allows us to maximize our skillset while providing an important service for the hospital during this crisis. Additionally, this model allows us to control our own workforce and preserve workforce availability in the likely event that some of our providers contract the disease

Improving estimates of children living with HIV from the Spectrum AIDS Impact Model

Objective: Estimated numbers of children living with HIV determine programmatic and treatment needs. We explain the changes made to the UNAIDS estimates between 2015 and 2016, and describe the challenges around these estimates. Methods: Estimates of children newly infected, living with HIV, and dying of AIDS are developed by country teams using Spectrum software. Spectrum files are available for 160 countries, which represent 98% of the global population. In 2016, the methods were updated to reflect the latest evidence on mother-to-child HIV transmission and improved assumptions on the age children initiate antiretroviral therapy. We report updated results using the 2016 model and validate these estimates against mother-to-child transmission rates and HIV prevalence from population-based surveys for the survey year. Results: The revised 2016 model estimates 27% fewer children living with HIV in 2014 than the 2015 model, primarily due to changes in the probability of mother-to-child transmission among women with incident HIV during pregnancy. The revised estimates were consistent with population-based surveys of HIV transmission and HIV prevalence among children aged 5–9 years, but were lower than surveys among children aged 10–14 years. Conclusions: The revised 2016 model is an improvement on previous models. Paediatric HIV models will continue to evolve as further improvements are made to the assumptions. Commodities forecasting and programme planning rely on these estimates, and increasing accuracy will be critical to enable effective scale-up and optimal use of resources. Efforts are needed to improve empirical measures of HIV prevalence, incidence, and mortality among children

Interaction of opiate peptide and noradrenalin systems: Light microscopic studies

In this light microscopic immunocyto-chemical study [beta]-Endorphin ([beta]-END), leu-enkephalin and dopamine-[beta]hydroxylase (DBH) antisera are used to obtain an overview of the interaction of the noradrenergic and opiate peptide systems in brain. Serial brain areas were analyzed for DBH and then for [beta]-END or leu-enkephalin. Several areas were evaluated for cell and fiber interactions between these systems. The areas of richest possible contact between [beta]-END and DBH positive systems include the rostral locus coeruleus region, the periaqueductal grey, possibly the dorsal thalamus, the paraventricular hypothalamus and the arcuate nucleus. Enkephalin cells and fibers were seen surrounding the locus coeruleus throughout its length with a few fibers in the nucleus itself.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23268/1/0000205.pd

Early Infant Diagnosis of HIV in Three Regions in Tanzania; Successes and Challenges.

By the end of 2009 an estimated 2.5 million children worldwide were living with HIV-1, mostly as a consequence of vertical transmission, and more than 90% of these children live in sub-Saharan Africa. In 2008 the World Health Organization (WHO), recommended early initiation of Highly Active Antiretroviral Therapy (HAART) to all HIV infected infants diagnosed within the first year of life, and since 2010, within the first two years of life, irrespective of CD4 count or WHO clinical stage. The study aims were to describe implementation of EID programs in three Tanzanian regions with differences in HIV prevalences and logistical set-up with regard to HIV DNA testing. Data were obtained by review of the prevention from mother to child transmission of HIV (PMTCT) registers from 2009-2011 at the Reproductive and Child Health Clinics (RCH) and from the databases from the Care and Treatment Clinics (CTC) in all the three regions; Kilimanjaro, Mbeya and Tanga. Statistical tests used were Poisson regression model and rank sum test. During the period of 2009 - 2011 a total of 4,860 exposed infants were registered from the reviewed sites, of whom 4,292 (88.3%) were screened for HIV infection. Overall proportion of tested infants in the three regions increased from 77.2% in 2009 to 97.8% in 2011. A total of 452 (10.5%) were found to be HIV infected (judged by the result of the first test). The prevalence of HIV infection among infants was higher in Mbeya when compared to Kilimanjaro region RR = 1.872 (95%CI = 1.408 - 2.543) p < 0.001. However sample turnaround time was significantly shorter in both Mbeya (2.7 weeks) and Tanga (5.0 weeks) as compared to Kilimanjaro (7.0 weeks), p=<0.001. A substantial of loss to follow-up (LTFU) was evident at all stages of EID services in the period of 2009 to 2011. Among the infants who were receiving treatment, 61% were found to be LFTU during the review period. The study showed an increase in testing of HIV exposed infants within the three years, there is large variations of HIV prevalence among the regions. Challenges like; sample turnaround time and LTFU must be overcome before this can translate into the intended goal of early initiation of lifelong lifesaving antiretroviral therapy for the infants

Cost-Effectiveness of World Health Organization 2010 Guidelines for Prevention of Mother-to-Child HIV Transmission in Zimbabwe

Background. In 2010, the World Health Organization (WHO) released revised guidelines for prevention of mother-to-child human immunodeficiency virus (HIV) transmission (PMTCT). We projected clinical impacts, costs, and cost-effectiveness of WHO-recommended PMTCT strategies in Zimbabwe. Methods. We used Zimbabwean data in a validated computer model to simulate a cohort of pregnant, HIV-infected women (mean age, 24 years; mean CD4 count, 451 cells/µL; subsequent 18 months of breastfeeding). We simulated guideline-concordant care for 4 PMTCT regimens: single-dose nevirapine (sdNVP); WHO-recommended Option A, WHO-recommended Option B, and Option B+ (lifelong maternal 3-drug antiretroviral therapy regardless of CD4). Outcomes included maternal and infant life expectancy (LE) and lifetime healthcare costs (2008 US dollars [USD]). Incremental cost-effectiveness ratios (ICERs, in USD per year of life saved [YLS]) were calculated from combined (maternal + infant) discounted costs and LE. Results. Replacing sdNVP with Option A increased combined maternal and infant LE from 36.97 to 37.89 years and would reduce lifetime costs from $5760 to$5710 per mother–infant pair. Compared with Option A, Option B further improved LE (38.32 years), and saved money within 4 years after delivery ($5630 per mother–infant pair). Option B+ (LE, 39.04 years; lifetime cost,$6620 per mother–infant pair) improved maternal and infant health, with an ICER of $1370 per YLS compared with Option B. Conclusions. Replacing sdNVP with Option A or Option B will improve maternal and infant outcomes and save money; Option B increases health benefits and decreases costs compared with Option A. Option B+ further improves maternal outcomes, with an ICER (compared with Option B) similar to many current HIV-related healthcare interventions

Cost-effectiveness of Routine Provider-Initiated Testing and Counseling for Children With Undiagnosed HIV in South Africa

Background: We compared the cost-effectiveness of pediatric provider-initiated HIV testing and counseling (PITC) vs no PITC in a range of clinical care settings in South Africa. Methods: We used the Cost-Effectiveness of Preventing AIDS Complications Pediatric model to simulate a cohort of children, aged 2-10 years, presenting for care in 4 settings (outpatient, malnutrition, inpatient, tuberculosis clinic) with varying prevalence of undiagnosed HIV (1.0%, 15.0%, 17.5%, 50.0%, respectively). We compared "PITC" (routine testing offered to all patients; 97% acceptance and 71% linkage to care after HIV diagnosis) with no PITC. Model outcomes included life expectancy, lifetime costs, and incremental cost-effectiveness ratios (ICERs) from the health care system perspective and the proportion of children with HIV (CWH) diagnosed, on antiretroviral therapy (ART), and virally suppressed. We assumed a threshold of $3200/year of life saved (YLS) to determine cost-effectiveness. Sensitivity analyses varied the age distribution of children seeking care and costs for PITC, HIV care, and ART. Results: PITC improved the proportion of CWH diagnosed (45.2$710 to $1240/YLS. PITC remained cost-effective unless undiagnosed HIV prevalence was <0.2%. Conclusions: Routine testing improves HIV clinical outcomes and is cost-effective in South Africa if the prevalence of undiagnosed HIV among children exceeds 0.2%. These findings support current recommendations for PITC in outpatient, inpatient, tuberculosis, and malnutrition clinical settings

Weekly SARS-CoV-2 screening of asymptomatic kindergarten to grade 12 students and staff helps inform strategies for safer in-person learning

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission in K-12 schools was rare during in 2020-2021; few studies included Centers for Disease Control and Prevention (CDC)-recommended screening of asymptomatic individuals. We conduct a prospective observational study of SARS-CoV-2 screening in a mid-sized suburban public school district to evaluate the incidence of asymptomatic coronavirus disease 2019 (COVID-19), document frequency of in-school transmission, and characterize barriers and facilitators to asymptomatic screening in schools. Staff and students undergo weekly pooled testing using home-collected saliva samples. Identification of \u3e 1 case in a school prompts investigation for in-school transmission and enhancement of safety strategies. With layered mitigation measures, in-school transmission even before student or staff vaccination is rare. Screening identifies a single cluster with in-school staff-to-staff transmission, informing decisions about in-person learning. The proportion of survey respondents self-reporting comfort with in-person learning before versus after implementation of screening increases. Costs exceed $260,000 for assays alone; staff and volunteers spend 135-145 h per week implementing screening