On the Nature of the Rotational Energy Barrier of Atropisomeric Hydrazides

N-N atropisomers represent a useful class of compounds that has recently received important attention from many research groups. This article presents an in-depth analysis of the energy barrier needed for the racemization process of atropoisomeric hydrazides, combining an experimental and computational approach. The focus is on examining how electronic and steric factors impact the racemization process. The results obtained indicate that the barrier observed during the racemization process mainly arises from an increase in the p-orbital character of the nitrogen atoms

Determinants of multidrug-resistant tuberculosis in Addis Ababa, Ethiopia

Demelash Assefa,1 Berhanu Seyoum,2 Lemessa Oljira2 1KNCV Tuberculosis Foundation, Addis Ababa, 2School of Public Health, College of Health and Medical Sciences, Haramaya University, Harar, Ethiopia Abstract: Multidrug-resistant tuberculosis (MDR-TB) has been jeopardizing the global effort to prevent and control tuberculosis (TB). However, data on MDR-TB in Ethiopia in general, and in our study area in particular, are very scarce. The aim of this study was to identify determinants of MDR-TB in a cohort of patients managed in two referral hospitals of Addis Ababa, Ethiopia, between April 1, 2013 and June 30, 2013. A health facility-based case–control study was conducted. A total of 710 TB patients (229 confirmed MDR-TB and 481 drug susceptible TB patients) were enrolled in this study. Identified independent determinants for MDR-TB were contact history with a known TB patient (adjusted odds ratio [AOR]: 1.9, 95% CI: 1.1–3.3), previous history of TB treatment (AOR: 11.9, 95% CI: 6.8–21), history of hospitalization (AOR: 4.4 95% CI: 2.2–7.8), sputum-smear positivity (AOR: 1.9, 95% CI: 1.1–3.4), and social stigma (AOR: 5.1, 95% CI: 1.8–14.4). These identified factors should be considered for use in MDR-TB screening tool development if universal drug susceptibility testing is not possible. Moreover, TB infection control practices in health care settings should be further strengthened. As factors may vary from region to region, further broader studies need to be conducted in other parts of Ethiopia. Keywords: MDR-TB, drug susceptible TB, determinants, sputum smear positive, treatment completed, cured, drug susceptibility testin

Factors affecting acceptance of provider-initiated HIV testing and counseling services among outpatient clients in selected health facilities in Harar Town, Eastern Ethiopia

Sami Abdurahman,1 Berhanu Seyoum,2 Lemessa Oljira,2 Fitsum Weldegebreal2 1Harari Regional Health Bureau, 2Haramaya University, College of Health and Medical Sciences, Harar, Ethiopia Purpose: To improve the slow uptake of HIV counseling and testing, the World Health Organization (WHO) and the Joint United Nations Programme on HIV/AIDS (UNAIDS) have developed draft guidelines on provider-initiated testing and counseling (PITC). Both in low- and high-income countries, mainly from outpatient clinics and tuberculosis settings, indicates that the direct offer of HIV testing by health providers can result in significant improvements in test uptake. In Ethiopia, there were limited numbers of studies conducted regarding PITC in outpatient clinics. Therefore, in this study, we have assessed the factors affecting the acceptance of PITC among outpatient clients in selected health facilities in Harar, Harari Region State, Ethiopia. Materials and methods: Institutional-based, cross-sectional quantitative and qualitative studies were conducted from February 12–30, 2011 in selected health facilities in Harar town, Harari Region State, Ethiopia. The study participants were recruited from the selected health facilities of Harar using a systematic random sampling technique. The collected data were double entered into a data entry file using Epi Info version 3.5.1. The data were transferred to SPSS software version 16 and analyzed according to the different variables. Results: A total of 362 (70.6%) clients accepted PITC, and only 39.4% of clients had heard of PITC in the outpatient department service. Age, occupation, marital status, anyone who wanted to check their HIV status, and the importance of PITC were the variables that showed significant associations with the acceptance of PITC upon bivariate and multivariate analyses. The main reasons given for not accepting the tests were self-trust, not being at risk for HIV, not being ready, needing to consult their partners, a fear of the results, a shortage of staff, a busy work environment, a lack of private rooms, and a lack of refresher training, which were identified as the main barriers for PITC. Conclusion: There is evidence of the relatively increased acceptability of PITC services by outpatient department clients. A program needs to be strengthened to enhance the use of PITC; the Ministry of Health, Regional Health Bureau, and other responsible bodies – including health facilities – should design and strengthen information education and communication/behavioral change and communication interventions and promote activities related to PITC and HIV counseling and testing in both health facilities and the community at large. Keywords: PITC, outpatient clients, Harar town, Eastern Ethiopi

Multiple Rare Variants as a Cause of a Common Phenotype: Several Different Lactase Persistence Associated Alleles in a Single Ethnic Group

Persistence of intestinal lactase into adulthood allows humans to use milk from other mammals as a source of food and water. This genetic trait has arisen by convergent evolution and the derived alleles of at least three different single nucleotide polymorphisms (-13910C > T, -13915T > G, -14010G > C) are associated with lactase persistence in different populations. Each allele occurs on an extended haplotype, consistent with positive directional selection. The SNPs are located in an 'enhancer' sequence in an intron of a neighboring gene (MCM6) and modulate lactase transcription in vitro. However, a number of lactase persistent individuals carry none of these alleles, but other low-frequency single nucleotide polymorphisms have been observed in the same region. Here we examine a cohort of 107 milk-drinking Somali camel-herders from Ethiopia. Eight polymorphic sites are identified in the enhancer. -13915*G and -13907*G (a previously reported candidate) are each significantly associated with lactase persistence. A new allele, -14009*G, has borderline association with lactase persistence, but loses significance after correction for multiple testing. Sequence diversity of the enhancer is significantly higher in the lactase persistent members of this and a second cohort compared with non-persistent members of the two groups (P = 7.7 x 10(-9) and 1.0 x 10(-3)). By comparing other loci, we show that this difference is not due to population sub-structure, demonstrating that increased diversity can accompany selection. This contrasts with the well-documented observation that positive selection decreases diversity by driving up the frequency of a single advantageous allele, and has implications for association studies

Tuberculosis Prevalence and Predictors Among Health Care-Seeking People Screened for Cough of Any Duration in Ethiopia: A Multicenter Cross-Sectional Study

Background: Tuberculosis (TB) remains a major cause of morbidity and mortality in sub-Saharan Africa. This high burden is mainly attributed to low case detection and delayed diagnosis. We aimed to determine the prevalence and predictors of TB among health care-seeking people screened for cough of any duration in Ethiopia. Methods: In this multicenter cross-sectional study, we screened 195,713 (81.2%) for cough of any duration. We recruited a sample of 1,853 presumptive TB (PTB) cases and assigned them into three groups: group I with cough ≥2 weeks, group II with cough of Results: The overall prevalence of PTB was 16.7% (309/1853). Of the positive cases, 81.2% (251/309) were in group I (cough ≥2 weeks), 14.2% (44/309) in group II (cough of Conclusion: The prevalence of confirmed PTB among routine outpatients was high, and this included those with a low duration of cough who can serve as a source of infection. Screening all patients at outpatient departments who passively report any cough irrespective of duration is important to increase TB case finding and reduce TB transmission and mortality.</p