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1.
John N. Freskos Bethel Asmelash Kimberly R. Gaston Amol Karwa Tim A. Marzan Maureen A. Nickols Thomas E. Rogers Tasha Schoenstein Carolyn J. Sympson Bich Vu 《Bioorganic & medicinal chemistry letters》2013,23(20):5566-5570
We describe the synthesis, MMP-2 and 9 potency, and in vitro evaluation of a series of α-sulfone hydroxmate MMP inhibitors conjugated to a series of dyes with different absorption/emission lamina maxima’s that can be used to visualize tumors. 相似文献
2.
Kelemework Adane Mark Spigt Semaw Ferede Tsehaye Asmelash Markos Abebe Geert-Jan Dinant 《PloS one》2016,11(2)
Introduction
Prison settings have been often identified as important but neglected reservoirs for TB. This study was designed to determine the prevalence of undiagnosed pulmonary TB and assess the potential risk factors for such TB cases in prisons of the Tigray region.Method
A cross-sectional study was conducted between August 2013 and February 2014 in nine prisons. A standardized symptom-based questionnaire was initially used to identify presumptive TB cases. From each, three consecutive sputum samples were collected for acid-fast bacilli (AFB) microscopy and culture. Blood samples were collected from consented participants for HIV testing.Result
Out of 809 presumptive TB cases with culture result, 4.0% (95% CI: 2.65–5.35) were confirmed to have undiagnosed TB. The overall estimated point prevalence of undiagnosed TB was found to be 505/100,000 prisoners (95% CI: 360–640). Together with the 27 patients who were already on treatment, the overall estimated point prevalence of TB would be 793/100,000 prisoners (95% CI: 610–970), about four times higher than in the general population. The ratio of active to passive case detection was 1.18:1. The prevalence of HIV was 4.4% (36/809) among presumptive TB cases and 6.3% (2/32) among undiagnosed TB cases. In a multivariate logistic regression analysis, chewing Khat (adjusted OR = 2.81; 95% CI: 1.02–7.75) and having had a close contact with a TB patient (adjusted OR = 2.18; 95% CI: 1.05–4.51) were found to be predictors of undiagnosed TB among presumptive TB cases.Conclusions
This study revealed that at least half of symptomatic pulmonary TB cases in Northern Ethiopian prisons remain undiagnosed and hence untreated. The prevalence of undiagnosed TB in the study prisons was more than two folds higher than in the general population of Tigray. This may indicate the need for more investment and commitment to improving TB case detection in the study prisons. 相似文献3.
Scott Dryden-Peterson Kara Bennett Michael D. Hughes Adrian Veres Oaitse John Rosina Pradhananga Matthew Boyer Carolyn Brown Bright Sakyi Erik van Widenfelt Koona Keapoletswe Madisa Mine Sikhulile Moyo Aida Asmelash Mark Siedner Mompati Mmalane Roger L. Shapiro Shahin Lockman 《PloS one》2015,10(2)
BackgroundLess than one-third of HIV-infected pregnant women eligible for combination antiretroviral therapy (ART) globally initiate treatment prior to delivery, with lack of access to timely CD4 results being a principal barrier. We evaluated the effectiveness of an SMS-based intervention to improve access to timely antenatal ART.MethodsWe conducted a stepped-wedge cluster randomized trial of a low-cost programmatic intervention in 20 antenatal clinics in Gaborone, Botswana. From July 2011-April 2012, 2 clinics were randomly selected every 4 weeks to receive an ongoing clinic-based educational intervention to improve CD4 collection and to receive CD4 results via an automated SMS platform with active patient tracing. CD4 testing before 26 weeks gestation and ART initiation before 30 weeks gestation were assessed.ResultsThree-hundred-sixty-six ART-naïve women were included, 189 registering for antenatal care under Intervention and 177 under Usual Care periods. Of CD4-eligible women, 100 (59.2%) women under Intervention and 79 (50.6%) women under Usual Care completed CD4 phlebotomy before 26 weeks gestation, adjusted odds ratio (aOR, adjusted for time that a clinic initiated Intervention) 0.87 (95% confidence interval [CI]0.47–1.63, P = 0.67). The SMS-based platform reduced time to clinic receipt of CD4 test result from median of 16 to 6 days (P<0.001), was appreciated by clinic staff, and was associated with reduced operational cost. However, rates of ART initiation remained low, with 56 (36.4%) women registering under Intervention versus 37 (24.2%) women under Usual Care initiating ART prior to 30 weeks gestation, aOR 1.06 (95%CI 0.53–2.13, P = 0.87).ConclusionsThe augmented SMS-based intervention delivered CD4 results more rapidly and efficiently, and this type of SMS-based results delivery platform may be useful for a variety of tests and settings. However, the intervention did not appear to improve access to timely antenatal CD4 testing or ART initiation, as obstacles other than CD4 impeded ART initiation during pregnancy. 相似文献
4.
Ineke?van?Gremberghe Katleen?Van der?Gucht Pieter?Vanormelingen Tsehaye?Asmelash Tadesse?Dejenie Sofie?D’hondt Steven?Declerck Luc?De?Meester Wim?VyvermanEmail author 《Aquatic Ecology》2011,45(2):289-306
The cyanobacterium Microcystis is notorious for forming extensive and potentially toxic blooms in nutrient-rich freshwater bodies worldwide. However, little
is known about the factors underlying the genetic diversity and structure of natural Microcystis populations, despite the fact that this knowledge is essential to understand the build-up of blooms. Microcystis blooms are common and occur year-round in Africa, but are underinvestigated in this continent. We studied the genetic diversity
and structure of Microcystis populations in 30 man-made reservoirs in Tigray (Northern Ethiopia) using Denaturing Gradient Gel Electrophoresis of the
16S–23S rDNA internal transcribed spacer (ITS) region and assessed the importance of local environmental conditions and geographic
position of the reservoirs for the observed patterns. The analyses showed that both regional and local Microcystis ITS diversity in these recently constructed reservoirs was relatively low, with several dense blooms containing only a single
ITS type. Especially one non-toxic ITS type dominated a considerable fraction of Microcystis blooms, but appeared restricted in its geographic distribution. The relationship between Microcystis ITS population structure and abiotic variables (water clarity, pH) and with zooplankton (Daphnia biomass) indicates a (limited) influence of environmental conditions on Microcystis population structure in the reservoirs of Tigray. 相似文献
5.
Poreddy AR Neumann WL Freskos JN Rajagopalan R Asmelash B Gaston KR Fitch RM Galen KP Shieh JJ Dorshow RB 《Bioorganic & medicinal chemistry》2012,20(8):2490-2497
Novel pyrazine carboxamides bearing hydrophilic poly(ethylene glycol) (PEG) moieties were designed, synthesized, and evaluated for use as fluorescent glomerular filtration rate (GFR) tracer agents. Among these, compounds 4d and 5c that contain about 48 ethylene oxide units in the PEG chain exhibited the most favorable physicochemical and renal clearance properties. In vitro studies show that these two compounds have low plasma protein binding, a necessary condition for renal excretion. In vivo animal model results show that 4d and 5c have a higher urine recovery of the injected dose than iothalamate (a commonly considered gold standard GFR agent). Pharmacokinetic studies show that these two compounds exhibit a plasma clearance equivalent to iothalamate, but with a faster (i.e. lower) terminal half-life than iothalamate (possibly from restricted distribution into the extracellular space due to large molecular size and hydrodynamic volume). Furthermore, the plasma clearance of 4d and 5c remained unchanged upon blockage of the tubular secretion pathway with probenecid, a necessary condition for establishment of clearance via glomerular filtration exclusively. Finally, noninvasive real-time monitoring of this class of compounds was demonstrated by pharmacokinetic clearance of 5c by optical measurements in rat model, which correlates strongly with plasma concentration of the tracer. Hence, 4d and 5c are promising candidates for translation to the clinic as exogenous fluorescent tracer agents in real-time point-of-care monitoring of GFR. 相似文献
6.
Yemane Tsehaye Trygve Berg Bayush Tsegaye Tesema Tanto 《Biodiversity and Conservation》2006,15(13):4289-4308
Tigray (region) is one of the major finger millet growing regions in Ethiopia and an important site from an archeobotanical
point of view. Three zones of Tigray (east, central and west) were identified as representative sites in the region and a
total of 14 districts/ ‘Woreda’ were surveyed. Thirty-seven landraces/farmers’ varieties of finger millet were identified/recorded.
Farmers in Tigray undertake pre and post harvest selection in finger millet and sometimes they also select seeds from storage
based on a number of attributes. Farmers maintain diversity as a way to ensure harvest security or stability of production,
to promote diversity of diet and income sources, minimize crop failure risk, reduce insect and disease incidences and ensure
efficient use of labour. The traditional management of finger millet in the entire study area is generally found to be demand
driven, showing the existence of potential sites for on-farm conservation. The high morphological diversity (H =0.76 ± 0.09)
found in the gene bank collections of Tigrayan origin also reveals the importance of linking ex situ with in situ conservation activities. Furthermore, the enhancement and conservation significance of the crop is discussed. 相似文献
7.
Vladimir Novitsky Rui Wang Hermann Bussmann Shahin Lockman Marianna Baum Roger Shapiro Ibou Thior Carolyn Wester C. William Wester Anthony Ogwu Aida Asmelash Rosemary Musonda Adriana Campa Sikhulile Moyo Erik van Widenfelt Madisa Mine Claire Moffat Mompati Mmalane Joseph Makhema Richard Marlink Peter Gilbert George R. Seage III Victor DeGruttola M. Essex 《PloS one》2010,5(4)
The first aim of the study is to assess the distribution of HIV-1 RNA levels in subtype C infection. Among 4,348 drug-naïve HIV-positive individuals participating in clinical studies in Botswana, the median baseline plasma HIV-1 RNA levels differed between the general population cohorts (4.1–4.2 log10) and cART-initiating cohorts (5.1–5.3 log10) by about one log10. The proportion of individuals with high (≥50,000 (4.7 log10) copies/ml) HIV-1 RNA levels ranged from 24%–28% in the general HIV-positive population cohorts to 65%–83% in cART-initiating cohorts. The second aim is to estimate the proportion of individuals who maintain high HIV-1 RNA levels for an extended time and the duration of this period. For this analysis, we estimate the proportion of individuals who could be identified by repeated 6- vs. 12-month-interval HIV testing, as well as the potential reduction of HIV transmission time that can be achieved by testing and ARV treating. Longitudinal analysis of 42 seroconverters revealed that 33% (95% CI: 20%–50%) of individuals maintain high HIV-1 RNA levels for at least 180 days post seroconversion (p/s) and the median duration of high viral load period was 350 (269; 428) days p/s. We found that it would be possible to identify all HIV-infected individuals with viral load ≥50,000 (4.7 log10) copies/ml using repeated six-month-interval HIV testing. Assuming individuals with high viral load initiate cART after being identified, the period of high transmissibility due to high viral load can potentially be reduced by 77% (95% CI: 71%–82%). Therefore, if HIV-infected individuals maintaining high levels of plasma HIV-1 RNA for extended period of time contribute disproportionally to HIV transmission, a modified “test-and-treat” strategy targeting such individuals by repeated HIV testing (followed by initiation of cART) might be a useful public health strategy for mitigating the HIV epidemic in some communities. 相似文献
8.
Spatial and temporal isolation and environmental variability are important factors explaining variation in plant species composition. The effect of fragmentation and disturbance on woody plant species composition was studied using data from 32 remnant church forest patches in northern Ethiopia. The church forests are remnants of dry Afromontane forest, embedded in a matrix of intensively used crop and grazing lands. We used canonical correspondence analysis and partial canonical correspondence analysis to analyze the effects of fragmented and isolated forest-patch identity, environmental and spatial variables on woody plant species composition in different growth stages. The dominance of late successional species was higher at the adult growth stage than seedlings and saplings growth stages. In the adult stages, late successional species like Olea europaea subsp. cuspidate had high frequency of occurrence. Forest patch identity was more important in explaining woody plant assemblages than environmental and spatial variables. For all growth stages combined, environmental variables explained more of the explained total fraction of variation in species composition than spatial variables. Topographic variables best explained variations in species composition for saplings, adults and all growth stages combined, whereas the management regime was most important for seedlings species composition. Our results show that in a matrix of cultivated and grazing land, fragmented and isolated forest patches differ in woody plant species assemblages. Some species are widely distributed and occurred in many patches while other occurred only in one or a few forest patches. Thus, our results indicate that remnant forest patches are important for preserving rare plant species and therefore management practices should focus on minimizing disturbance to the church forests and if possible increase church forest patch size. 相似文献
9.
Wang Hongyan Ai Jie Shopit Abdullah Niu Mengyue Ahmed Nisar Tesfaldet Tsehaye Tang Zhongyuan Li Xiaodong Jamalat Yazeed Chu Peng Peng Jinyong Ma Xiaodong Qaed Eskandar Han Guozhu Zhang Weisheng Wang Jun Tang Zeyao 《Cell biology and toxicology》2022,38(3):531-551
Cell Biology and Toxicology - Diabetes mellitus (DM) is a metabolic syndrome, caused by insufficient insulin secretion or insulin resistance (IR). DM enhances oxidative stress and induces... 相似文献
10.
Sebastian Bott Tsehaye Tesfamariam Hande Candan Ismail Cakmak Volker Römheld Günter Neumann 《Plant and Soil》2008,312(1-2):185-194
This investigation demonstrated potential detrimental side effects of glyphosate on plant growth and micronutrient (Mn, Zn) status of a glyphosate-resistant (GR) soybean variety (Glycine max cv. Valiosa), which were found to be highly dependent on the selected growth conditions. In hydroponic experiments with sufficient Mn supply [0.5 μM], the GR cv. Valiosa produced similar plant biomass, root length and number of lateral roots in the control treatment without glyphosate as compared to its non-GR parental line cv. Conquista. However, this was associated with 50% lower Mn shoot concentrations in cv. Conquista, suggesting a higher Mn demand of the transgenic cv. Valiosa under the selected growth conditions. Glyphosate application significantly inhibited root biomass production, root elongation, and lateral root formation of the GR line, associated with a 50% reduction of Mn shoot concentrations. Interestingly, no comparable effects were detectable at low Mn supply [0.1 μM]. This may indicate Mn-dependent differences in the intracellular transformation of glyphosate to the toxic metabolite aminomethylphosphonic acid (AMPA) in the two isolines. In soil culture experiments conducted on a calcareous loess sub-soil of a Luvisol (pH 7.6) and a highly weathered Arenosol (pH 4.5), shoot biomass production and Zn leaf concentrations of the GR-variety were affected by glyphosate applications on the Arenosol but not on the calcareous Loess sub-soil. Analysis of micronutrient levels in high and low molecular weight (LMW) fractions (80% ethanol extracts) of young leaves revealed no indications for internal immobilization of micronutrients (Mn, Zn, Fe) by excessive complexation with glyphosate in the LMW phase. 相似文献