In silico models for predicting vector control chemicals targeting Aedes aegypti.

Human arboviral diseases have emerged or re-emerged in numerous countries worldwide due to a number of factors including the lack of progress in vaccine development, lack of drugs, insecticide resistance in mosquitoes, climate changes, societal behaviours, and economical constraints. Thus, Aedes aegypti is the main vector of the yellow fever and dengue fever flaviviruses and is also responsible for several recent outbreaks of the chikungunya alphavirus. As for the other mosquito species, the A. aegypti control relies heavily on the use of insecticides. However, because of increasing resistance to the different families of insecticides, reduction of Aedes populations is becoming increasingly difficult. Despite the unquestionable utility of insecticides in fighting mosquito populations, there are very few new insecticides developed and commercialized for vector control. This is because the high cost of the discovery of an insecticide is not counterbalanced by the 'low profitability' of the vector control market. Fortunately, the use of quantitative structure-activity relationship (QSAR) modelling allows the reduction of time and cost in the discovery of new chemical structures potentially active against mosquitoes. In this context, the goal of the present study was to review all the existing QSAR models on A. aegypti. The homology and pharmacophore models were also reviewed. Specific attention was paid to show the variety of targets investigated in Aedes in relation to the physiology and ecology of the mosquito as well as the diversity of the chemical structures which have been proposed, encompassing man-made and natural substances.

Impact of the Xpert(®) MTB/RIF molecular test on the late diagnosis of pulmonary tuberculosis.

We analysed the impact of the Xpert(®) MTB/RIF molecular test on health-care diagnostic delay among tuberculosis patients. Diagnostic delay was 17.2 days (standard deviation 23.2, median 10 days). Of 128 patients recruited into the study, 60 (47%) were smear-negative; of these, 40 (67%) were Xpert-positive and were started on treatment without culture. The sensitivity of smear microscopy was 53% compared with 82% for Xpert. In smear-negative patients, delay in Xpert-positive and -negative patients was respectively 15.5 ± 13.2 and 25.5 ± 12.5 days (P = 0.002). We conclude that Xpert results were significantly associated with shorter health-care diagnostic delay, particularly in smear-negative patients.

[Bronchial-associated lymphoid tissue lymphoma]. / Linfoma de tejido linfoide asociado al bronquio (BALT).

Two cases of non-Hodgkin's endobronchial or bronchial-associated lymphoid tissue lymphoma are reported; such cases are either extremely rare or underestimated. We emphasize the need to perform endoscopic examination in patients with lymphoma and clinical findings that suggest bronchial disease.