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Background
Every year 40,000 people die of malaria in Burkina Faso. In 2010, the Burkinabè authorities implemented a national malaria control program that provides for the distribution of mosquito nets and the home-based treatment of children with fever by community health workers. The objective of this study was to measure the implementation fidelity of this program.Methods
We conducted a case study in two comparable districts (Kaya and Zorgho). Data were collected one year after the program’s implementation through field observations (10 weeks), documentary analysis, and individual interviews with stakeholders (n = 48) working at different levels of the program. The analysis framework looked at the fidelity of (i) the intervention’s content, (ii) its coverage, and (iii) its schedule.Results
The program’s implementation was relatively faithful to what was originally planned and was comparable in the two districts. It encountered certain obstacles in terms of the provision of supplies. Coverage fidelity was better in Kaya than in Zorgho, where many community health workers (CHW) experienced problems with the restocking of artemisinin-based combination therapy and with remuneration for periods of training. In both districts, the community was rarely involved in the process of selecting CHWs. The components affected by scheduling all experienced successive implementation delays that pushed nets distribution and the initial provision of artemisinin-based combination therapies to the CHWs past the 2010 malaria season.Conclusions
The activities intended by the program were mostly implemented with good fidelity. However, the implementation was plagued by delays that probably postponed the expected beneficial effects. 相似文献4.
Ben Fredj R Gross E Chouchen L B'Chir F Ben Ahmed S Neubauer S Kiechle M Saguem S 《Comptes rendus biologies》2007,330(10):764-769
Dihydropyrimidine dehydrogenase enzyme (DPD) deficiency is a pharmacogenetic syndrome leading to severe side-effects in patients receiving therapies containing the anticancer drug 5-fluorouracil (5-FU). The aim of this population study is to evaluate gene variations in the coding region of the dihydropyrimidine dehydrogenase gene (DPYD) in the Tunisian population. One hundred and six unrelated healthy Tunisian volunteers were genotyped by denaturing HPLC (DHPLC). Twelve variants in the coding region of the DPYD were detected. Allele frequencies of DPYD*5 (A1627G), DPYD*6 (G2194A), DPYD*9A (T85C), A496G, and G1218A were 12.7%, 7.1%, 13.7%, 5.7%, and 0.5%, respectively. The DPYD alleles DPYD*2A (IVS 14+1g>1), DPYD*3 (1897 del C) and DPYD*4 (G1601A) associated with DPD deficiency were absent from the examined subjects. We describe for the first time a new intronic polymorphism IVS 6-29 g>t, found in an allelic frequency of 4.7% in the Tunisian population. Comparing our data with that obtained in Caucasian, Egyptian, Japanese and African-American populations, we found that the Tunisian population resembles Egyptian and Caucasian populations with regard to their allelic frequencies of DPYD polymorphisms. This study describes for the first time the spectrum of DPYD sequence variations in the Tunisian population. 相似文献
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A 4 kb BamHI-HindIII fragment, corresponding to the cry2A operon of Bacillus thuringiensis subsp. kurstaki strain BNS3, was cloned. The sequencing of the corresponding cry2Aa-type gene, termed crybns3-4, revealed an open reading frame of 1902 bp, encoding a protein of 633 amino-acid residues. Both nucleotide and amino-acid sequences similarity analysis revealed that crybns3-4 is a new cry2Aa-type gene which has several differences from the reported cry2Aa-type genes. The transfer of the cloned operon to an acrystalliferous mutant of BNS3, revealed an expression of the new cry2Aa-type gene and a production of parasporal crystal inclusions in the transformants. 相似文献
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Two novel assay systems for the determination of sialyltransferase activity using a tetramethylrhodamine-labeled disaccharide Galbeta1-4GlcNAc (2) as the acceptor are described. The TMR-labeled disaccharide 2 was synthesized by directly coupling Galbeta1-4GlcNAc-O-(CH(2))(6)NH(2) (1) with 5-tetramethylrhodamine N-hydroxysuccinimide ester. The K(m) value for compound 2 obtained with alpha-2,6-sialyltransferase from rat liver (EC 2.4.99.1) was 160 +/- 20 microM. After incubation of compound 2 with sialyltransferase the product and the unreacted acceptor substrate were separated either by thin-layer chromatography (TLC) on C-18 silica gel plates or by polyacrylamide gel electrophoresis (PAGE). The density of the spots on the TLC plates and the fluorescence of the bands on the gel were quantified. The assay conditions were optimized using crude bovine colostrum extract and also alpha-2, 6-sialyltransferase from rat liver. The detection limits for the TLC and PAGE assays were 1 and 0.4 microU of the rat liver enzyme, respectively. Either assay allows the parallel investigation of several samples at a time and is useful for the testing of fractions during enzyme purification. 相似文献
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Amira Moussa Jihène Rejeb Asma Omezzine Lamia Rebhi Imen Boumaiza Slim Kacem Nabila Ben Rejeb Essia Boughzala Ahmed Ben Abdelaziz Ali Bouslama 《Biochemical genetics》2014,52(5-6):269-282
Haptoglobin (Hp) polymorphism generates three common human genotypes (Hp1-1, Hp2-1, and Hp2-2), having functional differences, related to the risk of development of cardiovascular diseases. These functions are a consequence of hemoglobin binding that leads to the synthesis of an antioxidant like ferritin. We explored the association of Hp polymorphism with significant coronary stenosis (SCS) and its severity within 400 Tunisian patients, using genotyping, biochemical parameters, and the Gensini score. After adjustments for age and gender, Hp2-2 was associated with the highest ferritin but the lowest Hp concentrations. After adjustments for confounding parameters, the OR of SCS associated with Hp2-2 was 1.74 (95% CI 1.18–2.58; p = 0.005). This effect was enhanced within diabetics (OR 1.90, 95% CI 1.11–3.24; p = 0.018), obese subjects (OR 1.98, 95% CI 1.10–4.86; p = 0.034), and smokers (OR 4.17, 95% CI 1.54–1.29; p = 0.005). The Hp2-2 genotype is associated with an increase in SCS especially in diabetics, the obese, and smokers. 相似文献
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Neil E. Olszewski Christopher M. West Slim O. Sassi Lynn M. Hartweck 《Biochimica et Biophysica Acta (BBA)/General Subjects》2010
The role in plants of posttranslational modification of proteins with O-linked N-acetylglucosamine and the evolution and function of O-GlcNAc transferases responsible for this modification are reviewed. Phylogenetic analysis of eukaryotic O-GlcNAc transferases (OGTs) leads us to propose that plants have two distinct OGTs, SEC- and SPY-like, that originated in prokaryotes. Animals and some fungi have a SEC-like enzyme while plants have both. Green algae and some members of the Apicomplexa and amoebozoa have the SPY-like enzyme. Interestingly the progenitor of the Apicomplexa lineage likely had a photosynthetic plastid that persists in a degenerated form in some species, raising the possibility that plant SPY-like OGTs are derived from a photosynthetic endosymbiont. OGTs have multiple tetratricopeptide repeats (TPRs) that within the SEC- and SPY-like classes exhibit evidence of strong selective pressure on specific repeats, suggesting that the function of these repeats is conserved. SPY-like and SEC-like OGTs have both unique and overlapping roles in the plant. The phenotypes of sec and spy single and double mutants indicate that O-GlcNAc modification is essential and that it affects diverse plant processes including response to hormones and environmental signals, circadian rhythms, development, intercellular transport and virus infection. The mechanistic details of how O-GlcNAc modification affects these processes are largely unknown. A major impediment to understanding this is the lack of knowledge of the identities of the modified proteins. 相似文献
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The evolution of seminal ribonuclease: pseudogene reactivation or multiple gene inactivation events?
Two approaches, one novel, are applied to analyze the divergent evolution of ruminant seminal ribonucleases (RNases), paralogs of the well-known pancreatic RNases of mammals. Here, the goal was to identify periods of divergence of seminal RNase under functional constraints, periods of divergence as a pseudogene, and periods of divergence driven by positive selection pressures. The classical approach involves the analysis of nonsynonymous to synonymous replacements ratios (omega) for the branches of the seminal RNase evolutionary tree. The novel approach coupled these analyses with the mapping of substitutions on the folded structure of the protein. These analyses suggest that seminal RNase diverged during much of its history after divergence from pancreatic RNase as a functioning protein, followed by homoplastic inactivations to create pseudogenes in multiple ruminant lineages. Further, they are consistent with adaptive evolution only in the most recent episode leading to the gene in modern oxen. These conclusions contrast sharply with the view, cited widely in the literature, that seminal RNase decayed after its formation by gene duplication into an inactive pseudogene, whose lesions were repaired in a reactivation event. Further, the 2 approaches, omega estimation and mapping of replacements on the protein structure, were compared by examining their utility for establishing the functional status of the seminal RNase genes in 2 deer species. Hog and roe deer share common lesions, which strongly suggests that the gene was inactive in their last common ancestor. In this specific example, the crystallographic approach made the correct implication more strongly than the omega approach. Studies of this type should contribute to an integrated framework of tools to assign functional and nonfunctional episodes to recently created gene duplicates and to understand more broadly how gene duplication leads to the emergence of proteins with novel functions. 相似文献