584 research outputs found

    Di- and Trinuclear Mixed-Valence Copper Amidinate Complexes from Reduction of Iodine

    Get PDF
    Molecular examples of mixed-valence copper complexes through chemical oxidation are rare but invoked in the mechanism of substrate activation, especially oxygen, in copper-containing enzymes. To examine the cooperative chemistry between two metals in close proximity to each other we began studying the reactivity of a dinuclear Cu(I) amidinate complex. The reaction of [(2,6-Me2C6H3N)2C(H)]2Cu2, 1, with I2 in tetrahydrofuran (THF), CH3CN, and toluene affords three new mixed-valence copper complexes [(2,6-Me2C6H3N)2C(H)]2Cu2(μ2-I3)(THF)2, 2, [(2,6-Me2C6H3N)2C(H)]2Cu2(μ2-I) (NCMe)2, 3, and [(2,6-Me2C6H3N)2C(H)]3Cu3(μ3-I)2, 4, respectively. The first two compounds were characterized by UV-vis and electron paramagnetic resonance spectroscopies, and their molecular structure was determined by X-ray crystallography. Both di- and trinuclear mixed-valence intermediates were characterized for the reaction of compound 1 to compound 4, and the molecular structure of 4 was determined by X-ray crystallography. The electronic structure of each of these complexes was also investigated using density functional theory

    Photoreactive Stapled BH3 Peptides to Dissect the BCL-2 Family Interactome

    Get PDF
    SummaryDefining protein interactions forms the basis for discovery of biological pathways, disease mechanisms, and opportunities for therapeutic intervention. To harness the robust binding affinity and selectivity of structured peptides for interactome discovery, we engineered photoreactive stapled BH3 peptide helices that covalently capture their physiologic BCL-2 family targets. The crosslinking α helices covalently trap both static and dynamic protein interactors, and enable rapid identification of interaction sites, providing a critical link between interactome discovery and targeted drug design

    Loss to follow-up in a community clinic in South Africa – roles of gender, pregnancy and CD4 count

    Get PDF
    Background. Faith-based organisations have expanded antiretroviral therapy (ART) in community clinics across South Africa. Loss to follow-up (LTFU), however, limits the potential individual and population treatment benefits and optimal care. Objective. To identify patient characteristics associated with LTFU 6 months after starting ART in a large community clinic. Methods. Patients initiating ART between April 2004 and October 2006 in one South African Catholic Bishops’ Conference HIV treatment clinic who had at least one follow-up visit were included and routinely monitored every 6 months after ART initiation. Standardised instruments were used to collect data. Rates of LTFU over time were estimated by the Kaplan-Meier method. The Cox proportional hazard regression examined the impact of age, baseline CD4 count, baseline HIV RNA, gender and pregnancy status on LTFU. Results. Data from 925 patients (age >14 years, median age 36 years, 70% female, of whom 16% were pregnant) were included: 51 (6%) were lost to follow-up 6 months after ART initiation. Younger age (≤30 years) (hazard ratio (HR) 2.14, 95% confidence interval (CI) 1.05 - 4.38) and pregnancy for women (HR 3.75, 95% CI 1.53 - 9.16) were significantly associated with higher LTFU rates. When stratified by baseline CD4 count, gender and pregnancy status, pregnant women with lower baseline CD4 counts (≤200 cells/ μl) had 6.06 times the hazard (95% CI 2.20 - 16.71) of LTFU at 6 months compared with men. Conclusions. HIV-infected pregnant women initiating ART were significantly more likely to be lost to follow-up in a community clinic in South Africa. Urgent interventions to successfully retain pregnant women in care are needed

    Predictors of mortality in patients initiating antiretroviral therapy in Durban, South Africa

    Get PDF
    Objective. To identify predictors of mortality in patients initiating antiretroviral therapy (ART) in Durban, South Africa. Design. We conducted a retrospective cohort study analysing data on patients who presented to McCord Hospital, Durban, and started ART between 1 January 1999 and 29 February 2004. We performed univariate and multivariate analysis and constructed Kaplan-Meier curves to assess predictors. Results. Three hundred and nine patients were included. Forty-nine (16%) had died by the conclusion of the study. In univariate analysis, the strongest predictors of mortality were a CD4 cell coun

    The impact of HIV/HCV co-infection on health care utilization and disability: results of the ACTG Longitudinal Linked Randomized Trials (ALLRT) Cohort.

    Get PDF
    HIV/hepatitis C virus (HCV) co-infection places a growing burden on the HIV/AIDS care delivery system. Evidence-based estimates of health services utilization among HIV/HCV co-infected patients can inform efficient planning. We analyzed data from the ACTG Longitudinal Linked Randomized Trials (ALLRT) cohort to estimate resource utilization and disability among HIV/HCV co-infected patients and compare them to rates seen in HIV mono-infected patients. The analysis included HIV-infected subjects enrolled in the ALLRT cohort between 2000 and 2007 who had at least one CD4 count measured and completed at least one resource utilization data collection form (N = 3143). Primary outcomes included the relative risk of hospital nights, emergency department (ED) visits, and disability days for HIV/HCV co-infected vs HIV mono-infected subjects. When controlling for age, sex, race, history of AIDS-defining events, current CD4 count and current HIV RNA, the relative risk of hospitalization, ED visits, and disability days for subjects with HIV/HCV co-infection compared to those with HIV mono-infection were 1.8 (95% CI: 1.3-2.5), 1.7 (95% CI: 1.4-2.1), and 1.6 (95% CI: 1.3-1.9) respectively. Programs serving HIV/HCV co-infected patients can expect approximately 70% higher rates of utilization than expected from a similar cohort of HIV mono-infected patients

    Routine Rapid HIV Screening in Six Community Health Centers Serving Populations at Risk

    Get PDF
    In 2006, to increase opportunities for patients to become aware of their HIV status, the Centers for Disease Control and Prevention released updated guidelines for routine, opt-out HIV screening of adults, adolescents, and pregnant women in healthcare settings. To date, there are few documented applications of these recommendations. To measure the impact of application of the guidelines for routine screening in health centers serving communities disproportionately affected by HIV in the southeastern US. A multi-site program implementation study, describing patients tested and not tested and assessing changes in testing frequency before and after new guidelines were implemented. All patients aged 13 to 64 seen in participating health centers. Routine rapid HIV screening in accord with CDC guidelines. The frequency of testing before and after routine screening was in place and demographic differences in offering and receipt of testing. Compared to approximately 3,000 patients in the year prior to implementation, 16,148 patients were offered testing with 10,769 tested. Of 39 rapid tests resulting in preliminary positives, 17 were newly detected infections. Among these patients, 12 of 14 receiving referrals were linked to HIV care. Nineteen were false positives. Younger patients, African Americans and Latinos were more likely to receive testing. By integrating CDC-recommended guidelines and applying rapid test technology, health centers were able to provide new access to HIV testing. Variation across centers in offering and receiving tests may indicate that clinical training could enhance universal access

    Clinical Practices for Measles-Mumps-Rubella Vaccination Among US Pediatric International Travelers.

    Get PDF
    Importance: The US population is experiencing a resurgence of measles, with more than 1000 cases during the first 6 months of 2019. Imported measles cases among returning international travelers are the source of most US measles outbreaks, and these importations can be reduced with pretravel measles-mumps-rubella (MMR) vaccination of pediatric travelers. Although it is estimated that children account for less than 10% of US international travelers, pediatric travelers account for 47% of all known measles importations. Objective: To examine clinical practice regarding MMR vaccination of pediatric international travelers and to identify reasons for nonvaccination of pediatric travelers identified as MMR eligible. Design, Setting, and Participants: This cross-sectional study of pediatric travelers (ages ≥6 months and \u3c18 \u3eyears) attending pretravel consultation at 29 sites associated with Global TravEpiNet (GTEN), a Centers for Disease Control and Prevention-supported consortium of clinical sites that provide pretravel consultations, was performed from January 1, 2009, through December 31, 2018. Main Outcomes and Measures: Measles-mumps-rubella vaccination among MMR vaccination-eligible pediatric travelers. Results: Of 14 602 pretravel consultations for pediatric international travelers, 2864 travelers (19.6%; 1475 [51.5%] males; 1389 [48.5%] females) were eligible to receive pretravel MMR vaccination at the time of the consultation: 365 of 398 infants aged 6 to 12 months (91.7%), 2161 of 3623 preschool-aged travelers aged 1 to 6 years (59.6%), and 338 of 10 581 school-aged travelers aged 6 to 18 years (3.2%). Of 2864 total MMR vaccination-eligible travelers, 1182 (41.3%) received the MMR vaccine and 1682 (58.7%) did not. The MMR vaccination-eligible travelers who did not receive vaccine included 161 of 365 infants (44.1%), 1222 of 2161 preschool-aged travelers (56.5%), and 299 of 338 school-aged travelers (88.5%). We observed a diversity of clinical practice at different GTEN sites. In multivariable analysis, MMR vaccination-eligible pediatric travelers were less likely to be vaccinated at the pretravel consultation if they were school-aged (model 1: odds ratio [OR], 0.32 [95% CI, 0.24-0.42; P \u3c .001]; model 2: OR, 0.26 [95% CI, 0.14-0.47; P \u3c .001]) or evaluated at specific GTEN sites (South: OR, 0.06 [95% CI, 0.01-0.52; P \u3c .001]; West: OR, 0.10 [95% CI, 0.02-0.47; P \u3c .001]). The most common reasons for nonvaccination were clinician decision not to administer MMR vaccine (621 of 1682 travelers [36.9%]) and guardian refusal (612 [36.4%]). Conclusions and Relevance: Although most infant and preschool-aged travelers evaluated at GTEN sites were eligible for pretravel MMR vaccination, only 41.3% were vaccinated during pretravel consultation, mostly because of clinician decision or guardian refusal. Strategies may be needed to improve MMR vaccination among pediatric travelers and to reduce measles importations and outbreaks in the United States

    Does Modality of Survey Administration Impact Data Quality: Audio Computer Assisted Self Interview (ACASI) Versus Self-Administered Pen and Paper?

    Get PDF
    BACKGROUND. In the context of a randomized controlled trial (RCT) on HIV testing in the emergency department (ED) setting, we evaluated preferences for survey modality and data quality arising from each modality. METHODS. Enrolled participants were offered the choice of answering a survey via audio computer assisted self-interview (ACASI) or pen and paper self-administered questionnaire (SAQ). We evaluated factors influencing choice of survey modality. We defined unusable data for a particular survey domain as answering fewer than 75% of the questions in the domain. We then compared ACASI and SAQ with respect to unusable data for domains that address sensitive topics. RESULTS. Of 758 enrolled ED patients, 218 (29%) chose ACASI, 343 chose SAQ (45%) and 197 (26%) opted not to complete either. Results of the log-binomial regression indicated that older (RR=1.08 per decade) and less educated participants (RR=1.25) were more likely to choose SAQ over ACASI. ACASI yielded substantially less unusable data than SAQ. CONCLUSIONS. In the ED setting there may be a tradeoff between increased participation with SAQ versus better data quality with ACASI. Future studies of novel approaches to maximize the use of ACASI in the ED setting are needed.National Institute of Mental Health (R01 MH073445, R01 MH65869
    corecore