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51.
Juliana Cogo Juan Cantizani Ignacio Cotillo Diego Pereira Sangi Arlene Gonçalves Corrêa Tânia Ueda-Nakamura Benedito Prado Dias Filho José Julio Martín Celso Vataru Nakamura 《Bioorganic & medicinal chemistry》2018,26(14):4065-4072
Continuous efforts have been made to discover new drugs for the treatment of Chagas’ disease, human African trypanosomiasis, and leishmaniasis. We have previously reported the synthesis and antileishmanial and antitrypanosomal (Y strain) properties of 2,3-disubstituted quinoxalines. Considering their promising antiparasitic potential, the present study was conducted to expand our search and take advantage of high-throughput assays to investigate the effects of quinoxaline derivatives against Leishmania donovani, Trypanosoma brucei, and Trypanosoma cruzi (Tulahuen strain). These compounds were active against the kinetoplastid parasites that were evaluated. The 2-chloro-3-methylsulfoxylsulfonyl and 2-chloro-3-methylsulfinyl quinoxalines were the most potent, and some of these derivatives were even more active than the reference drugs. Although the 2,3-diaryl-substituted quinoxalines were not active against all of the parasites, they were active against T. brucei and intracellular amastigotes of T. cruzi, without interfering with mammalian cell viability. These compounds presented encouraging results that will guide our future studies on in vivo bioassays towards the mode of action. 相似文献
52.
Miguel Santana de Almeida Neto Carolina Alves Collier de Almeida José Souto Rosa Filho Ana Carla Asfora El-Deir José da Silva Mourão 《Human ecology: an interdisciplinary journal》2018,46(4):561-571
Ecological models derived from Optimal Foraging Theory have been used to understand the decision-making processes and optimization of artisanal fisheries. However, many studies do not consider the influence of fishing techniques or seasonality on foraging strategies. We analyzed the optimization strategies and decision-making processes of the fishers at a Brazilian reservoir. Data were collected through interviews and questionnaires involving 65 artisanal fishers, and daily catches were monitored in July/2015 and January/2016. Fishing techniques and seasonality influenced the fishers’ behavior. The fishery activities monitored here were partially or totally consistent with the predictions of the Central-Place Foraging model, but due to the complexity of these activities, other factors also influenced the decision-making of individual fishers. Furthermore, the adoption of strategies that involve “non-ideal” behaviors may be advantageous for the fishers in the context of their individual necessities. 相似文献
53.
de Castro Assumpção Daniel Rivera Elmer Alberto Ccopa Tovar Laura Plazas Ezeji Thaddeus Chukwuemeka Filho Rubens Maciel Mariano Adriano Pinto 《Bioprocess and biosystems engineering》2018,41(11):1651-1663
Bioprocess and Biosystems Engineering - In flexible ethanol-butanol plants, low tolerance to butanol by solventogenic clostridia (and resulting dilute fermentation) results in considerable number... 相似文献
54.
V. A. F. Alves A. Castelo A. L. Filho M. R. Vianna E. Taromaru G. Namiyama A. Lorincz G. B. D. Dores DNA-Citoliq Working Group São Paulo Brazil 《Cytopathology》2006,17(2):86-93
OBJECTIVE: To evaluate the performance of a new, manual, simplified liquid-based system, DNA-Citoliq (Digene Brasil), employed under routine conditions as compared to conventional smears collected from six collaborating private laboratories. METHODS: A panel of cytopathologists, who served as the gold standard diagnosis, adjudicated discordant opinions. RESULTS: Of 3206 pairs of slides considered valid for comparison, there were 3008 in full agreement (93.8%), 112 (3.5%) with one diagnostic category discrepancies, and 86 (2.7%) discordant cases. Among the 288 borderline+ by either method, DNA-Citoliq detected abnormalities in 243 (84.4%), and conventional smears (CS) detected abnormalities in 178 (61.8%) (McNemar test, P < 0.000), a 36.5% increased detection of borderline+ cases. CONCLUSIONS: For mild dyskaryosis, DNA-Citoliq detected 176 cases and CS 125 cases (McNemar test, P < 0.000); and for moderate+severe dyskaryosis 66 versus 32 cases respectively (McNemar test, P < 0.000). 相似文献
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Saraiva L Andrade Filho JD Silva Sde O Andrade AS Melo MN 《Memórias do Instituto Oswaldo Cruz》2010,105(8):1033-1039
Over the last 20 years, there has been an increase in the number of leishmaniasis cases in Brazil. Belo Horizonte (BH) is one of the most highly populated Brazilian cities that is affected by visceral leishmaniasis (VL). The health services in BH are coordinated by a central nucleus that is subdivided into nine sanitary districts. Historically, the highest level of human VL cases was found in the northeast sanitary district (NSD). The objective of our study was to detect Leishmania infection in the phlebotomine sand flies collected in the NSD by dissection and molecular approaches. Following the occurrence of human VL cases in 2005, entomological captures were performed from July 2006-June 2007. Out of the 245 sand flies dissected, only three Lutzomyia longipalpis spp contained flagellates. The female sand flies were grouped into 120 pools according to date, collection site and species, with approximately 10 individual sand flies in each pool. Subsquently, the DNA was extracted and Leishmania spp and other parasites were detected and identified by polymerase chain reaction (PCR) and PCR-restriction fragment length polymorfism. Leishmania infantum was present in at least 19% of the Lu. longipalpis collected, in 3.8% of the Nyssomiya whitmani collected, in 33.3% of the Evandromiya termitophila collected and in 14.3% of the Nyssomiya intermedia collected. When the females of the cortelezzii complex were compared with each other, 3.2% of the females were infected with Leishmania braziliensis, whereas 3.2% of the females were infected with trypanosomatids. 相似文献
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59.
Evlyn Márcia Leão de Moraes Novo Cláudio Clemente de Farias Barbosa Ramon Moraes de Freitas Yosio Edimir Shimabukuro John M. Melack Waterloo Pereira Filho 《Limnology》2006,7(3):153-161
To assess seasonal changes in phytoplanktonic chlorophyll distributions in Amazon floodplain lakes, a linear mixing model
was applied to Moderate Resolution Imaging Spectroradiometer (MODIS) reflectance data acquired at four river stages: rising
(April), high (June), decreasing (September), and low (November). The study area is located in a floodplain reach from Parintins
(Amazonas) to near Almeirim (Pará). A three-end-member mixing model designed to uncouple three fractions [high suspended inorganic
matter (ip), low inorganic suspended matter (w), and high chlorophyll a (Chl)] was tested in Lake Curuaí (1.5°S 55.43°W) based on field sampling done almost concurrently with satellite overpasses.
During high water, phytoplankton patches are confined to lakes closer to terra firme under the influence of clear water inflow,
whereas during the low and decreasing water stages, the patches are more evenly distributed over the floodplain. 相似文献
60.
Wagner Serra e Silva Filho Renato C. V. Casarin Eduardo L. Nicolela Junior Humberto M. Passos Ant?nio W. Sallum Reginaldo B. Gon?alves 《PloS one》2014,9(10)