L'étude théorique d'oligomeres:rc-conjugués obtenus par association de thiophene avec le 1,4diaminobenzene est présentée. L'objectif est de comprendre l'influence de l'allongement de la chaîne sur ...les propriétés géométriques, optoélectroniques et photovoltaiques afin d'élaborer des nanostructures fortement л-conjuguées. La Théorie de la Fonctionnelle de Densité (DFT) avec la fonctionnelle hybride B3LYP ont servi a déterminer les propriétés structurales (distances inter-cycles, angles de torsion) et électroniques (l'énergie des orbitales HOMO et LUMO, la largeur de la bande interdite et l'énergie de chaque molécule). Les propriétés optiques (l'énergie d'excitation et la longueur d'onde d'absorption) ont été obtenues par la théorie de la fonctionnelle de la densité dépendante du temps (TD-DFT). L'étude révele que ces oligomeres possedent des structures partiellement planes avec de faibles largeurs de bande interdite. Les résultats de cette étude théorique montrent que ces composés possedent d'intéressantes propriétés et peuvent donc étre des candidats potentiels pour la conception de dispositifs optoélectroniques.
In the Sahelian countries, the degradation of surface water quality is the result of transportation of dissolved matter by the runoff. This study aims to analyze chemical processes that control the ...distribution of chemicals compounds in rainwater and runoff in the Sahelian watershed. The results show that rainwater has a neutral pH with the calcium chloride facies. They are strongly influenced by atmospheric dust coming from wind erosion of the soil watershed and the soil of Saharan desert, but also from agricultural activities. Runoff of Tougou watershed are calcium hydrogenocarbonate facies with a pH of 7.05 and an average temperature of 27 degree C. The chemical composition of runoff varies according to the physical environment of the sub-watershed. In the degraded sub-watershed (BVD), runoff have low mineralization compared to runoff of cultivated sub-watershed BVC (EC 27 pS.cm-1 on BVD and 83 pS.cm-1 on BVC). The total load dissolved is 66 mg.l-1for the runoff of BVD and 100 mg.l-1for the runoff of BVC.
In the Sahelian countries, the degradation of surface water quality is the result of transportation of dissolved matter by the runoff. This study aims to analyze chemical processes that control the ...distribution of chemicals compounds in rainwater and runoff in the Sahelian watershed. The results show that rainwater has a neutral pH with the calcium chloride facies. They are strongly influenced by atmospheric dust coming from wind erosion of the soil watershed and the soil of Saharan desert, but also from agricultural activities. Runoff of Tougou watershed are calcium hydrogenocarbonate facies with a pH of 7.05 and an average temperature of 27° C. The chemical composition of runoff varies according to the physical environment of the sub-watershed. In the degraded sub-watershed (BVD), runoff have low mineralization compared to runoff of cultivated sub-watershed BVC (EC 27 pS.cm-1 on BVD and 83 pS.cm-1 on BVC). The total load dissolved is 66 mg.l-1for the runoff of BVD and 100 mg.l-1for the runoff of BVC.
Summary Background Artemisinin-based combination regimens are widely advocated for malarial treatment, but other effective regimens might be cheaper and more readily available. Our aim was to compare ...the risk of recurrent parasitaemia in patients given artemether-lumefantrine with that in those given amodiaquine plus sulfadoxine-pyrimethamine for uncomplicated malaria. Methods We enrolled 521 patients aged 6 months or older with uncomplicated falciparum malaria in Bobo-Dioulasso, Burkina Faso. Patients were randomly assigned to receive standard doses of either artemether-lumefantrine (261) or amodiaquine plus sulfadoxine-pyrimethamine (260) for 3 days. Primary endpoints were the risks of treatment failure within 28 days, either unadjusted or adjusted by genotyping to distinguish recrudescence from new infection. The study is registered at controlled-trials.gov with the identifier ISRCTN54261005. Findings Of enrolled patients, 478 (92%) completed the 28-day study. The risk of recurrent symptomatic malaria was lowest in the group given amodiaquine plus sulfadoxine-pyrimethamine (1·7% vs 10·2%; risk difference 8·5%; 95% CI 4·3–12·6; p=0·0001); as was the risk of recurrent parasitaemia (4·7% vs 15·1%; 10·4%; 5·1–15·6; p=0·0002). Nearly all recurrences were due to new infections. Recrudescences were four late treatment failures with artemether-lumefantrine and one early treatment failure with amodiaquine plus sulfadoxine-pyrimethamine. Both regimens were safe and well tolerated, with pruritus more common with amodiaquine plus sulfadoxine-pyrimethamine than with artemether-lumefantrine. Each regimen selected for new isolates with mutations that have been associated with decreased drug susceptibility. Interpretation Amodiaquine plus sulfadoxine-pyrimethamine was more effective than was artemether-lumefantrine for the treatment of uncomplicated malaria. For regions of Africa where amodiaquine plus sulfadoxine-pyrimethamine continues to be effective, this less expensive and more available regimen should be considered as an alternative to blanket recommendations for artemisinin-based combination treatment for malaria.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Objectives
Artemisinin‐based combination therapies (ACTs) are essential for the effective control of falciparum malaria in endemic countries. However, in most countries, such choice has been carried ...out without knowing their effectiveness when deployed in real‐life conditions, that is, when treatment is not directly observed. We report here the results of a study assessing the effectiveness of the two ACTs currently recommended in Burkina Faso for the treatment of uncomplicated malaria, that is, artemether–lumefantrine (AL) and artesunate–amodiaquine (ASAQ).
Methods
Between September 2008 and January 2010, 340 children were randomised to one of the two study arms and followed up for 42 days. Treatment was administered according to routine practices, that is, the first dose was given by study nurses who explained to the parent/guardian how to administer the other doses at home during the following 2 days.
Results
The results showed a significantly higher unadjusted adequate clinical and parasitological response in the ASAQ (58.4%) than in the AL arm (46.1%) at day 28 but these trends were similar after correction with PCR data (ASAQ (89.7%) and AL (89.8%)). New infections started to appear after day 14, first in the AL and then in the ASAQ arm but at day 42 day of follow‐up we observed no difference in the occurrence of recrudescent infection.
Conclusion
Despite a lower cure rate than those reported in efficacy studies in which the treatment administration was directly observed, both AL and ASAQ can still be used for the treatment of uncomplicated malaria in Burkina Faso.
Objectifs
Les traitements de combinaison à base d'artémisinine (ACT) sont essentiels pour la lutte efficace contre le paludisme à falciparum dans les pays endémiques. Cependant, dans la plupart des pays, un tel choix a été fait sans connaître leur efficacité lorsqu'ils sont déployés dans des conditions réelles, c'est‐à‐dire, lorsque le traitement n'est pas directement observé. Nous rapportons ici les résultats d'une étude visant à évaluer l'efficacité des deux ACT actuellement recommandés au Burkina‐Faso pour le traitement du paludisme non compliqué, c'est‐à‐dire l'artéméther‐luméfantrine (AL) et l'artésunate‐amodiaquine (ASAQ).
Méthodes
Entre septembre 2008 et janvier 2010, 340 enfants ont été randomisés dans l'un des deux bras de l’étude et suivis pendant 42 jours. Le traitement a été administré selon les pratiques de routine, c'est à dire la première dose a été administrée par des infirmières de l’étude qui ont expliqué au parent/tuteur comment administrer les autres doses à la maison pendant les deux jours suivants.
Résultats
Les résultats ont montré une réponse clinique et parasitologique adéquate (RCPA) non ajustée significativement plus élevée dans le bras ASAQ (58.4 de%) que dans le bras AL (46.1%) au jour 28, mais ces tendances étaient similaires après correction avec les données de PCR (ASAQ (89.7%) et AL (89.8%)). Les nouvelles infections ont commencé à apparaître après le jour 14, d'abord dans le bras AL, puis dans le bras ASAQ mais au jour 42 de suivi, nous n'avons observé aucune différence dans l'incidence de recrudescence de l'infection.
Conclusion
Malgré un taux de guérison inférieur par rapport à ceux rapportés dans les études d'efficacité dans lesquelles l'administration du traitement a été directement observé, autant AL que ASAQ peut toujours être utilisé pour le traitement du paludisme non compliqué au Burkina‐Faso.
Objetivos
Las terapias de combinación de artemisinina (TCA) son esenciales para el control efectivo de la malaria por falciparum en países endémicos. Sin embargo, en la mayoría de los países esta opción se ha tomado sin conocer su efectividad en condiciones de la vida real, es decir cuando el tratamiento no se observa de forma directa. Reportamos los resultados de un estudio que evalúa la efectividad de las dos TCAs actualmente recomendadas en Burkina Faso para el tratamiento de la malaria no complicada, es decir artemeter‐lumefantrina (AL) y artesunato‐amodiaquina (ASAQ).
Métodos
Entre Septiembre 2008 y Enero 2010, se aleatorizaron 340 niños a uno de los dos brazos del estudio y se siguieron durante 42 días. Se administró el tratamiento según las prácticas rutinarias, es decir la primera dosis la entregó una enfermera del estudio que explicó al pariente/guardián como administrar las otras dosis en casa durante los siguientes dos días.
Resultado
Los resultados mostraban una respuesta clínica y parasitológica adecuada no ajustada significativamente mayor en el brazo de ASAQ (58.4%) que en el brazo AL (46.1%) a día 28, pero estas tendencias eran similares después de la corrección con datos de PCR (ASAQ (89.7%) y AL (89.8%)). Nuevas infecciones aparecieron después del día 14, primero en el brazo AL y después en el brazo ASAQ pero en el día 42 de seguimiento no se observaron diferencias en el recrudecimiento de la infección.
Conclusión
A pesar de haber encontrado una tasa de curación menor que aquellas reportados en estudios de eficacia en los que la administración del tratamiento se observaba de forma directa, se puede continuar utilizando tanto la AL como la ASAQ para el tratamiento de la malaria no complicada en Burkina Faso.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
We investigated the relationship between the two main molecular markers for chloroquine resistance (Pfcrt T76 and Pfmdr-1 Y86) and the clinical efficacy of amodiaquine in Burkina Faso. Before ...treatment, the prevalence of Pfcrt T76, Pfmdr-1 Y86 or both mutations in the same infection was significantly higher in patients who experienced a recrudescence than in those who successfully responded to the treatment. Therefore, these two molecular markers could be useful in monitoring amodiaquine resistance, particularly in countries where this drug is used in combination with artesunate as first- or second-line treatment.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Sulfadoxine-pyrimethamine efficacy was determined with a 28-day follow-up in 97 children between 6 months and 15 years of age. The polymerase chain reaction (PCR)-corrected treatment failure was 8.2% ...and the uncorrected was 21.6%. The presence of the dihydrofolate reductase (DHFR) and dihydropteroate synthetase (DHPS) mutations linked to sulfadoxine-pyrimethamine resistance before and after treatment was determined by PCR-restriction fragment length polymorphism (RFLP) and by a fluorogenic PCR assay. Before treatment, the prevalence of the triple DHFR mutations was higher among the patients having had a recurrent parasitemia (either recrudescence or new infection; 28.6% versus 9.3%), although the difference was not significant (P = 0.1). The double mutation Ala-436/Gly-437 was observed in 67% of samples, whereas no Glu-540 mutation was found. After treatment, the triple DHFR mutation was found in 76.2% of patients with recurrent parasitemia, recrudescence, and new infection alike. Such high prevalence of mutant parasites indicates that sulfadoxine-pyrimethamine should not be used as monotherapy.
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