排序方式: 共有27条查询结果,搜索用时 15 毫秒
1.
E Abate M Belayneh A Gelaw J Idh A Getachew S Alemu E Diro N Fikre S Britton D Elias A Aseffa O Stendahl T Schön 《PloS one》2012,7(8):e42901
Background
Areas endemic of helminth infection, tuberculosis (TB) and HIV are to a large extent overlapping. The aim of this study was to assess the impact of asymptomatic helminth infection on the immunological response among TB patients with and without HIV, their house hold contacts and community controls.Methodology
Consecutive smear positive TB patients (n = 112), their household contacts (n = 71) and community controls (n = 112) were recruited in Gondar town, Ethiopia. Stool microscopy, HIV serology, serum IgE level, eosinophil and CD4 counts were performed and tuberculosis patients were followed up for 3 months after initiation of anti-TB treatment.Results
Helminth co-infection rate was 29% in TB patients and 21% in both community control and household contacts (p = 0.3) where Ascaris lumbricoides was the most prevalent parasite. In TB patients the seroprevalence of HIV was 47% (53/112). Eosinophilia and elevated IgE level were significantly associated with asymptomatic helminth infection. During TB treatment, the worm infection rate of HIV+/TB patients declined from 31% (10/32) at week 0 to 9% (3/32) at week 2 of TB treatment, whereas HIV−/TB patients showed no change from baseline to week 2, 29% (13/45) vs. 22.2% (10/45). This trend was stable at week 8 and 12 as well.Conclusion
One third of smear positive TB patients were infected with helminths. Eosinophilia and elevated IgE level correlated with asymptomatic worm infection, indicating an effect on host immunity. The rate of worm infection declined during TB treatment in HIV+/TB co-infected patients whereas no decline was seen in HIV−/TB group. 相似文献2.
Background
The effects of prenatal Zinc Deficiency (ZD) and Vitamin A Deficiency (VAD) on birthweight are controversial and their interaction has not been investigated.Objective
To assess the independent and interaction effects of prenatal zinc and vitamin A deficiencies on birthweight in rural Sidama, Southern Ethiopia.Methodology
A community-based prospective cohort study design was employed. Six hundred fifty pregnant women in their second or third trimester were randomly selected and their serum zinc and retinol concentrations were determined. About 575 subjects were successfully followed until delivery and birthweight was measured within 72 hours after delivery. The association between the exposures and birthweight was examined using log-binomial and liner regression analyses. Potential interaction between ZD and VAD was examined using Synergy Index (SI).Results
The mean birthweight (± standard deviation) was 2896 g (±423). About 16.5% (95% CI: 13.5–19.6%) of the babies had Low Birthweight (LBW). Prenatal ZD and VAD were not significantly associated to LBW with Adjusted Relative Risk (ARR) of 1.25 (95 CI: 0.86–1.82) and 1.27 (95% CI: 0.86–1.87), respectively. Stratified analysis on the basis of gestational trimester showed that the occurrence of the deficiencies neither in the second nor third trimester were associated to LBW. The deficiencies did not show synergetic interaction in causing LBW [SI = 1.04 (95% CI: 0.17–6.28)]. Important risk factors of LBW were maternal illiteracy [RR = 1.80 (95% CI: 1.11–2.93)], female sex of the newborn [RR = 1.79 (95% CI: 1.19–2.67)], primiparity [RR = 1.16 (95% CI: 1.02–1.35)], short maternal stature [RR = 1.63 (95% CI: 1.06–2.51)] and maternal thinness [RR = 1.52 (95% CI: 1.03–2.25)]. In the linear regression model, elevated CRP was also negatively associated to birthweight.Conclusion
LBW is of public health significance in the locality. The study did not witness any independent or interaction effect of prenatal ZD and VAD on birthweight. 相似文献3.
Astrid C. Erber Victoria Ewing Mark Turner Meseret Molla Gharib Murbe Fikre Enquoselassie Gail Davey Trudie Lang 《PLoS neglected tropical diseases》2021,15(7)
BackgroundClinical trials are often perceived as being expensive, difficult and beyond the capacity of healthcare workers in low-resource settings. However, in order to improve healthcare coverage, the World Health Organization (WHO) World Health Report 2013 stated that all countries need to become generators as well as recipients of data. This study is a methodological examination of the steps and processes involved in setting up the Gojjam Lymphoedema Best Practice Trial (GoLBeT; ISRCTN67805210), a highly pragmatic clinical trial conducted in northern Ethiopia. Challenges to the trial and strategies used to deal with them were explored, together with the reasons for delays.Methodology and principal findingsQualitative research methods were used to analyse emails and reports from the period between trial inception and recruitment. This analysis was complemented by interviews with key informants from the trial operational team. The Global Health Research Process Map was used as a framework against which to compare the steps involved in setting up the trial. A mini-group discussion was conducted with the trial operational team after study completion for reflection and further recommendations.This study showed that the key areas of difficulty in setting up and planning this trial were: the study design, that is, deciding on the study endpoint, where and how best to measure it, and assuring statistical power; recruitment and appropriate training of staff; planning for data quality; and gaining regulatory approvals. Collaboration, for example with statisticians, the trial steering committee, the study monitors, and members of the local community was essential to successfully setting up the trial.Conclusions and significanceLessons learnt from this trial might guide others planning pragmatic trials in settings where research is not common, allowing them to anticipate possible challenges and address them through trial design, planning and operational delivery. We also hope that this example might encourage similar pragmatic studies to be undertaken. Such studies are rarely undertaken or locally led, but are an accessible and efficient way to drive improved outcomes in public health. 相似文献
4.
Yoshihiro Tohyama Sho Takahashi Maraki Fikre Merid Arata Watanabe Mirko Diksic 《Neurochemistry international》2002,40(7):576-610
The effects of the tryptophan hydroxylase (TPH) inhibitor p-chlorophenylalanine (PCPA; 200mg/kg; 3 days), and of the protein synthesis inhibitor cycloheximide (CXM, 2mg/kg), on regional serotonin (5-HT) synthesis were studied using the alpha-[14C]methyl-L-tryptophan (alpha-[14C]MTrp) autoradiographic method. The objectives of these investigations were to evaluate the changes, if any, on 5-HT synthesis, as measured with alpha-MTrp method, following the inhibition of TPH by PCPA, or the inhibition of proteins synthesis by CXM. The rats were used in the tracer experiment approximately 24h after the last dose of PCPA was administered, and in the CXM experiments, they were used 30 min following a single injection of CXM. In both experiments, the control rats were injected with the same volume of saline (0.5 ml/kg; s.c.) and at the same times as the drug injections. The results demonstrate that trapping of alpha-MTrp, which is taken to be related to brain 5-HT synthesis, is drastically reduced (40-80%) following PCPA treatment. The inhibition of protein synthesis with CXM did not have a significant effect on the global brain trapping of alpha-MTrp and 5-HT synthesis. These findings suggest that the brain trapping of alpha-[14C]MTrp relates to brain 5-HT synthesis, but not to brain protein synthesis. 相似文献
5.
Ermias Diro Koert Ritmeijer Marleen Boelaert Fabiana Alves Rezika Mohammed Charles Abongomera Raffaella Ravinetto Maaike De Crop Helina Fikre Cherinet Adera Robert Colebunders Harry van Loen Joris Menten Lutgarde Lynen Asrat Hailu Johan van Griensven 《PLoS neglected tropical diseases》2015,9(10)
Background
Visceral leishmaniasis (VL) has become an important opportunistic infection in persons with HIV-infection in VL-endemic areas. The co-infection leads to profound immunosuppression and high rate of annual VL recurrence. This study assessed the effectiveness, safety and feasibility of monthly pentamidine infusions to prevent recurrence of VL in HIV co-infected patients.Methods
A single-arm, open-label trial was conducted at two leishmaniasis treatment centers in northwest Ethiopia. HIV-infected patients with a VL episode were included after parasitological cure. Monthly infusions of 4mg/kg pentamidine-isethionate diluted in normal-saline were started for 12months. All received antiretroviral therapy (ART). Time-to-relapse or death was the primary end point.Results
Seventy-four patients were included. The probability of relapse-free survival at 6months and at 12 months was 79% and 71% respectively. Renal failure, a possible drug-related serious adverse event, occurred in two patients with severe pneumonia. Forty-one patients completed the regimen taking at least 11 of the 12 doses. Main reasons to discontinue were: 15 relapsed, five died and seven became lost to follow-up. More patients failed among those with a CD4+cell count ≤ 50cells/μl, 5/7 (71.4%) than those with counts above 200 cells/μl, 2/12 (16.7%), (p = 0.005).Conclusion
Pentamidine secondary prophylaxis led to a 29% failure rate within one year, much lower than reported in historical controls (50%-100%). Patients with low CD4+cell counts are at increased risk of relapse despite effective initial VL treatment, ART and secondary prophylaxis. VL should be detected and treated early enough in patients with HIV infection before profound immune deficiency installs. 相似文献6.
Sergio Pérez-Guerrero Asnake Gelan-Begna Rafael Tamajón Enrique Vargas-Osuna 《Biocontrol Science and Technology》2013,23(3):335-347
The relative feeding rates and preferences of a hunting-spider assemblage inhabiting southern Spanish cotton fields for two major cotton pests, Helicoverpa armigera (Hübner) and Spodoptera littoralis (Boisdubal) (Lepidoptera: Noctuidae), were analyzed under laboratory conditions. First, a no-choice feeding test was used to determine relative feeding rates for hunting-spider families and species, offering a fixed number of 10 neonate larvae of H. armigera or S. littoralis and observing predation after 2 h, 4 h, 8 h, and 24 h. In a second test, Drosophila melanogaster, a very palatable alternative prey, was used to determine the degree of preference for cotton pest larvae. The mean number of first-instar lepidoptera larvae consumed by hunting spiders after 24 h was 8.57±0.25. As expected, spiders showed no preference for either of the two cotton pest species H. armigera and S. littoralis over the other. Results also showed that cursorial spiders of the families Miturigidae (represented here by Cheiracanthium pelasgicum) and Philodromidae consumed significantly higher percentages of larvae than crab spiders belonging to the Thomisidae family after 2 h and 24 h, respectively. In the prey choice test, Cheiracantium pelasgicum displayed a strong preference for cotton pest larvae while Thomisidae and Oxyopidae showed no significant preference. In addition, as the attack sequence progressed, Ch. pelasgicum showed a clear tendency towards the alternation of prey while Thomisidae, and more irregularly Oxyopidae, maintained their preference for D. melanogaster. These findings confirmed both the considerable potential value of some cursorial spiders (e.g. Ch. pelasgicum) in the biological control of lepidopteran cotton pests and the relatively low impact of other hunting spiders, e.g. Thomisidae, on pests of this kind. 相似文献
7.
Structure and biological activities of beta toxin from Staphylococcus aureus 总被引:1,自引:0,他引:1 下载免费PDF全文
Huseby M Shi K Brown CK Digre J Mengistu F Seo KS Bohach GA Schlievert PM Ohlendorf DH Earhart CA 《Journal of bacteriology》2007,189(23):8719-8726
Beta toxin is a neutral sphingomyelinase secreted by certain strains of Staphylococcus aureus. This virulence factor lyses erythrocytes in order to evade the host immune system as well as scavenge nutrients. The structure of beta toxin was determined at 2.4-Å resolution using crystals that were merohedrally twinned. This structure is similar to that of the sphingomyelinases of Listeria ivanovii and Bacillus cereus. Beta toxin belongs to the DNase I folding superfamily; in addition to sphingomyelinases, the proteins most structurally related to beta toxin include human endonuclease HAP1, Escherichia coli endonuclease III, bovine pancreatic DNase I, and the endonuclease domain of TRAS1 from Bombyx mori. Our biological assays demonstrated for the first time that beta toxin kills proliferating human lymphocytes. Structure-directed active site mutations show that biological activities, including hemolysis and lymphotoxicity, are due to the sphingomyelinase activity of the enzyme. 相似文献
8.
Kebede Deribe Simon J. Brooker Rachel L. Pullan Asrat Hailu Fikre Enquselassie Richard Reithinger Melanie Newport Gail Davey 《PloS one》2013,8(7)
Background
An up-to-date and reliable map of podoconiosis is needed to design geographically targeted and cost-effective intervention in Ethiopia. Identifying the ecological correlates of the distribution of podoconiosis is the first step for distribution and risk maps. The objective of this study was to investigate the spatial distribution and ecological correlates of podoconiosis using historical and contemporary survey data.Methods
Data on the observed prevalence of podoconiosis were abstracted from published and unpublished literature into a standardized database, according to strict inclusion and exclusion criteria. In total, 10 studies conducted between 1969 and 2012 were included, and data were available for 401,674 individuals older than 15 years of age from 229 locations. A range of high resolution environmental factors were investigated to determine their association with podoconiosis prevalence, using logistic regression.Results
The prevalence of podoconiosis in Ethiopia was estimated at 3.4% (95% CI 3.3%–3.4%) with marked regional variation. We identified significant associations between mean annual Land Surface Temperature (LST), mean annual precipitation, topography of the land and fine soil texture and high prevalence of podoconiosis. The derived maps indicate both widespread occurrence of podoconiosis and a marked variability in prevalence of podoconiosis, with prevalence typically highest at altitudes >1500 m above sea level (masl), with >1500 mm annual rainfall and mean annual LST of 19–21°C. No (or very little) podoconiosis occurred at altitudes <1225 masl, with annual rainfall <900 mm, and mean annual LST of >24°C.Conclusion
Podoconiosis remains a public health problem in Ethiopia over considerable areas of the country, but exhibits marked geographical variation associated in part with key environmental factors. This is work in progress and the results presented here will be refined in future work. 相似文献9.
Rajeev K. Varshney S. Murali Mohan Pooran M. Gaur N.V.P.R. Gangarao Manish K. Pandey Abhishek Bohra Shrikant L. Sawargaonkar Annapurna Chitikineni Paul K. Kimurto Pasupuleti Janila K.B. Saxena Asnake Fikre Mamta Sharma Abhishek Rathore Aditya Pratap Shailesh Tripathi Subhojit Datta S.K. Chaturvedi Nalini Mallikarjuna G. Anuradha Anita Babbar Arbind K. Choudhary M.B. Mhase Ch. Bharadwaj D.M. Mannur P.N. Harer Baozhu Guo Xuanqiang Liang N. Nadarajan C.L.L. Gowda 《Biotechnology advances》2013
10.
Thomas M. Lampinen Keith Chan Robert S. Remis Maraki Fikre Merid Melanie Rusch Jean Vincelette Ken Logue Vladimir Popovic Michel Alary Martin T. Schechter Robert S. Hogg 《CMAJ》2005,172(4):479-483