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131.
Mng'ong'o FC Sambali JJ Sabas E Rubanga J Magoma J Ntamatungiro AJ Turner EL Nyogea D Ensink JH Moore SJ 《PloS one》2011,6(10):e25927
Sustained malaria control is underway using a combination of vector control, prompt diagnosis and treatment of malaria cases. Progress is excellent, but for long-term control, low-cost, sustainable tools that supplement existing control programs are needed. Conventional vector control tools such as indoor residual spraying and house screening are highly effective, but difficult to deliver in rural areas. Therefore, an additional means of reducing mosquito house entry was evaluated: the screening of mosquito house entry points by planting the tall and densely foliated repellent plant Lantana camara L. around houses. A pilot efficacy study was performed in Kagera Region, Tanzania in an area of high seasonal malaria transmission, where consenting families within the study village planted L. camara (Lantana) around their homes and were responsible for maintaining the plants. Questionnaire data on house design, socioeconomic status, malaria prevention knowledge, attitude and practices was collected from 231 houses with Lantana planted around them 90 houses without repellent plants. Mosquitoes were collected using CDC Light Traps between September 2008 and July 2009. Data were analysed with generalised negative binomial regression, controlling for the effect of sampling period. Indoor catches of mosquitoes in houses with Lantana were compared using the Incidence Rate Ratio (IRR) relative to houses without plants in an adjusted analysis. There were 56% fewer Anopheles gambiae s.s. (IRR 0.44, 95% CI 0.28-0.68, p<0.0001); 83% fewer Anopheles funestus s.s. (IRR 0.17, 95% CI 0.09-0.32, p<0.0001), and 50% fewer mosquitoes of any kind (IRR 0.50, 95% CI 0.38-0.67, p<0.0001) in houses with Lantana relative to controls. House screening using Lantana reduced indoor densities of malaria vectors and nuisance mosquitoes with broad community acceptance. Providing sufficient plants for one home costs US $1.50 including maintenance and labour costs, (30 cents per person). L. camara mode of action and suitability for mosquito control is discussed. 相似文献
132.
Background
Until now, little was known about the variation in incidence of twin births across developing countries, because national representative data was lacking. This study provides the first comprehensive overview of national twinning rates across the developing world on the basis of reliable survey data.Methods
Data on incidence of twinning was extracted from birth histories of women aged 15–49 interviewed in 150 Demographic and Health Surveys, held between 1987 and 2010 in 75 low and middle income countries. During the interview, information on all live births experienced by the women was recorded, including whether it was a singleton or multiple birth. Information was available for 2.47 million births experienced by 1.38 million women in a period of ten years before the interview. Twinning incidence was measured as the number of twin births per thousand births. Data for China were computed on the basis of published figures from the 1990 census. Both natural and age-standardized twinning rates are presented.Results/Conclusions
The very low natural twinning rates of 6–9 per thousand births previously observed in some East Asian countries turn out to be the dominant pattern in the whole South and South-East Asian region. Very high twinning rates of above 18 per thousand are not restricted to Nigeria (until now seen as the world''s twinning champion) but found in most Central-African countries. Twinning rates in Latin America turn out to be as low as those in Asia. Changes over time are small and not in a specific direction.Significance
We provide the most complete and comparable overview of twinning rates across the developing world currently possible. 相似文献133.
134.
van den Berg MA Albang R Albermann K Badger JH Daran JM Driessen AJ Garcia-Estrada C Fedorova ND Harris DM Heijne WH Joardar V Kiel JA Kovalchuk A Martín JF Nierman WC Nijland JG Pronk JT Roubos JA van der Klei IJ van Peij NN Veenhuis M von Döhren H Wagner C Wortman J Bovenberg RA 《Nature biotechnology》2008,26(10):1161-1168
135.
Mycobacterium avium subsp. paratuberculosis is a pathogen which causes a debilitating chronic enteritis in ruminants. Unfortunately, the mechanisms that control M. avium subsp. paratuberculosis persistence during infection are poorly understood and the key steps for developing Johne's disease remain elusive. A proteomic
analysis approach, based on one dimensional polyacrylamide gel electrophoresis (SDS-PAGE) followed by LC-MS/MS, was used to
identify and characterize the cell wall associated proteins of M. avium subsp. paratuberculosis K10 and an cell surface enzymatic shaving method was used to determine the surface-exposed proteins. 309 different proteins
were identified, which included 101 proteins previously annotated as hypothetical or conserved hypothetical. 38 proteins were
identified as surface-exposed by trypsin treatment. To categorize and analyze these proteomic data on the proteins identified
within cell wall of M. avium subsp. paratuberculosis K10, a rational bioinformatic approach was followed. The analyses of the 309 cell wall proteins provided theoretical molecular
mass and p I distributions and determined that 18 proteins are shared with the cell surface-exposed proteome. In short, a comprehensive
profile of the M. avium subsp. paratuberculosis K10 cell wall subproteome was created. The resulting proteomic profile might become the foundation for the design of new
preventive, diagnostic and therapeutic strategies against mycobacterial diseases in general and M. avium subsp. paratuberculosis in particular. 相似文献
136.
137.
Mary E. W. Dankbaar Karen M. Stegers-Jager Frank Baarveld Jeroen J. G. van Merrienboer Geoff R. Norman Frans L. Rutten Jan L. C. M. van Saase Stephanie C. E. Schuit 《PloS one》2014,9(12)
Objective
Each year over 1.5 million health care professionals attend emergency care courses. Despite high stakes for patients and extensive resources involved, little evidence exists on the quality of assessment. The aim of this study was to evaluate the validity and reliability of commonly used formats in assessing emergency care skills.Methods
Residents were assessed at the end of a 2-week emergency course; a subgroup was videotaped. Psychometric analyses were conducted to assess the validity and inter-rater reliability of the assessment instrument, which included a checklist, a 9-item competency scale and a global performance scale.Results
A group of 144 residents and 12 raters participated in the study; 22 residents were videotaped and re-assessed by 8 raters. The checklists showed limited validity and poor inter-rater reliability for the dimensions “correct” and “timely” (ICC = .30 and.39 resp.). The competency scale had good construct validity, consisting of a clinical and a communication subscale. The internal consistency of the (sub)scales was high (α = .93/.91/.86). The inter-rater reliability was moderate for the clinical competency subscale (.49) and the global performance scale (.50), but poor for the communication subscale (.27). A generalizability study showed that for a reliable assessment 5–13 raters are needed when using checklists, and four when using the clinical competency scale or the global performance scale.Conclusions
This study shows poor validity and reliability for assessing emergency skills with checklists but good validity and moderate reliability with clinical competency or global performance scales. Involving more raters can improve the reliability substantially. Recommendations are made to improve this high stakes skill assessment. 相似文献138.
van Oers Lauran Guinée Jeroen B. Heijungs Reinout 《The International Journal of Life Cycle Assessment》2020,25(2):309-310
The International Journal of Life Cycle Assessment - The original version of this article unfortunately contained a mistake which was missed during typesetting. The caption to Fig. 5 was... 相似文献
139.
The amino‐terminal tail of Hxt11 confers membrane stability to the Hxt2 sugar transporter and improves xylose fermentation in the presence of acetic acid 下载免费PDF全文
Hyun Yong Shin Jeroen G. Nijland Paul P. de Waal Arnold J. M. Driessen 《Biotechnology and bioengineering》2017,114(9):1937-1945
Hxt2 is a glucose repressed, high affinity glucose transporter of the yeast Saccharomyces cerevisiae and is subjected to high glucose induced degradation. Hxt11 is a sugar transporter that is stably expressed at the membrane irrespective the sugar concentration. To transfer this property to Hxt2, the N‐terminal tail of Hxt2 was replaced by the corresponding region of Hxt11 yielding a chimeric Hxt11/2 transporter. This resulted in the stable expression of Hxt2 at the membrane and improved the growth on 8% d ‐glucose and 4% d ‐xylose. Mutation of N361 of Hxt11/2 into threonine reversed the specificity for d ‐xylose over d ‐glucose with high d ‐xylose transport rates. This mutant supported efficient sugar fermentation of both d ‐glucose and d ‐xylose at industrially relevant sugar concentrations even in the presence of the inhibitor acetic acid which is normally present in lignocellulosic hydrolysates. Biotechnol. Bioeng. 2017;114: 1937–1945. © 2017 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc. 相似文献
140.
Integrin alpha4beta1 promotes focal adhesion kinase-independent cell motility via alpha4 cytoplasmic domain-specific activation of c-Src 下载免费PDF全文
Hsia DA Lim ST Bernard-Trifilo JA Mitra SK Tanaka S den Hertog J Streblow DN Ilic D Ginsberg MH Schlaepfer DD 《Molecular and cellular biology》2005,25(21):9700-9712
The fibronectin binding integrins alpha5beta1 and alpha4beta1 generate signals pivotal for cell migration through distinct yet undefined mechanisms. For alpha5beta1, beta1-mediated activation of focal adhesion kinase (FAK) promotes c-Src recruitment to FAK and the formation of a FAK-Src signaling complex. Herein, we show that FAK expression is essential for alpha5beta1-stimulated cell motility and that exogenous expression of human alpha4 in FAK-null fibroblasts forms a functional alpha4beta1 receptor that promotes robust cell motility equal to the alpha5beta1 stimulation of wild-type and FAK-reconstituted fibroblasts. alpha4beta1-stimulated FAK-null cell spreading and motility were dependent on the integrity of the alpha4 cytoplasmic domain, independent of direct paxillin binding to alpha4, and were not affected by PRNK expression, a dominant-negative inhibitor of Pyk2. alpha4 cytoplasmic domain-initiated signaling led to a approximately 4-fold activation of c-Src which did not require paxillin binding to alpha4. Notably, alpha4-stimulated cell motility was inhibited by catalytically inactive receptor protein-tyrosine phosphatase alpha overexpression and blocked by the p50Csk phosphorylation of c-Src at Tyr-529. alpha4beta1-stimulated cell motility of triple-null Src(-/-), c-Yes(-/-), and Fyn(-/-) fibroblasts was dependent on c-Src reexpression that resulted in p130Cas tyrosine phosphorylation and Rac GTPase loading. As p130Cas phosphorylation and Rac activation are common downstream targets for alpha5beta1-stimulated FAK activation, our results support the existence of a novel alpha4 cytoplasmic domain connection leading to c-Src activation which functions as a FAK-independent linkage to a common motility-promoting signaling pathway. 相似文献