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This study investigated the occurrence and seasonal distribution of different classes of pesticides in surface waters of the Ondas River Watershed, as well as potential risks to the aquatic health and human water consumption in the western region of Bahia state, Brazil. Two gas chromatography-mass spectrometry analytical methods were applied to monitor 34 pesticides in water samples collected during both the dry and rainy seasons at 17 sites. Upon individual analysis, only γ-HCH, methoxychlor, demeton-S, methyl parathion, fenitrothion, chlorpyrifos, and azoxystrobin exhibited statistically significant differences between seasons. During rainy season, concentration medians of residues were higher for γ-HCH (74.7 ng L -1 ), methoxychlor (25.1 ng L -1 ), and azoxystrobin (47.2 ng L -1 ), potentially linked to historical contamination or illegal use. Conversely, pesticides like methyl parathion, fenitrothion, and chlorpyrifos, belonging to the organophosphate class, showed higher concentration medians in the dry period, measuring 75.1, 5.50, and 10.8 ng L -1 , respectively, probably due to region crop activities. The risk quotient (RQ) assessment for aquatic life indicated that 59.0% of the samples in the dry season and 76.0% in the rainy season had RQ values greater than one, signifying a critical scenario for species conservation. Regarding human consumption, elevated risks were observed for heptachlor in both sampling periods and for azoxystrobin during the rainy season, surpassing RQ levels above 1, indicating danger in untreated water ingestion. Additionally, 24.0% and 53.0% of the samples in the dry and rainy seasons, respectively, contained at least one pesticide exceeding the EU resolution limit (100 ng L -1 ). Therefore, considering this information, implementing mitigation measures to avoid the river's contamination becomes imperative., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Antiretroviral therapy has significantly evolved in the last decade, with an increasing number of new drugs and classes. Currently, even heavily experienced patients can be successfully treated with new regimens. In Brazil, the recent incorporation of some new antiretroviral drugs made it possible to suppress HIV plasma viremia in most treated patients, with significant benefits in terms of quality of life and survival. However, little has been published on outcomes of patients under new drugs-based regimens. We reviewed the safety and efficacy of antiretroviral regimens using recently introduced drugs in Bahia. Our results confirm that patients using darunavir, raltegravir, enfuvirtide, or etravirine presented with a high rate of virological suppression without significant adverse events, after one year of follow-up., (Copyright © 2015 Elsevier Editora Ltda. All rights reserved.)

Mutations in the connection subdomain (CN) and RNase H domain (RH) of HIV-1 reverse transcriptase (RT) from subtype B-infected patients enhance nucleoside and nonnucleoside RT inhibitor (NRTI and NNRTI) resistance by affecting the balance between polymerization and RNase H activity. To determine whether CN mutations in subtype C influence drug sensitivity, single genome sequencing was performed on Brazilian subtype C-infected patients failing RTI therapy. CN mutations identified were similar to subtype B, including A376S, A400T, Q334D, G335D, N348I, and A371V, and increased AZT resistance in the presence of thymidine analog mutations. CN mutations also enhanced NNRTI resistance in the presence of classical NNRTI mutations: etravirine resistance was enhanced 6- to 11-fold in the presence of L100I/K103N/Y181C. These results indicate that selection of CN mutations in treatment-experienced patients also occurs in subtype-C-infected patients and are likely to provide valuable information in predicting clinical RTI resistance., (Published by Elsevier Inc.)

Nonnucleoside reverse transcriptase inhibitors (NNRTIs) are potent and well tolerated. In Brazil, the first-generation NNRTI efavirenz is included in the majority of first-line antiretroviral treatment regimens. In this study, we evaluated the effectiveness of etravirine, a new second-generation NNRTI, among patients failing antiretroviral regimens containing first-generation NNRTIs. We assessed single resistance mutations to etravirine as well as complex resistance mutations profile and discuss the potential of introducing etravirine as salvage therapy.