f Schistosomiasis is a chronic and debilitating disease caused by a trematode of the genus Schistosoma and affects over 207 million people. Chemotherapy is the only immediate recourse for minimizing the prevalence of this disease and involves predominately the administration of a single drug, praziquantel (PZQ). Although PZQ has proven efficacy, there is a recognized need to develop new drugs as schistosomicides since studies have shown that repeated use of this drug in areas of endemicity may cause a temporary reduction in susceptibility in isolates of Schistosoma mansoni. Hydrazones, thiosemicarbazones, phthalimides, and thiazoles are thus regarded as privileged structures used for a broad spectrum of activities and are potential candidates for sources of new drug prototypes. The present study determined the in vitro schistosomicidal activity of 10 molecules containing these structures. During the assays, parameters such motility and mortality, oviposition, morphological changes in the tegument, cytotoxicity, and immunomodulatory activity caused by these compounds were evaluated. The results showed that compounds formed of thiazole and phthalimide led to higher mortality of worms, with a significant decline in motility, inhibition of pairing and oviposition, and a mortality rate of 100% starting from 144 h of exposure. These compounds also stimulated the production of nitric oxide and tumor necrosis factor alpha (TNF-␣), thereby demonstrating the presence of immunomodulatory activity. The phthalyl thiazole LpQM-45 caused significant ultrastructural alterations, with destruction of the tegument in both male and female worms. According to the present study, phthalyl thiazole compounds possess antischistosomal activities and should form the basis for future experimental and clinical trials.

Chagas disease is a parasitic infection caused by protozoan Trypanosoma cruzi that affects approximately 6-7 million people worldwide. Benznidazole is the only drug approved for treatment during the acute and asymptomatic chronic phases; however, its efficacy during the symptomatic chronic phase is controversial. The present work reports the synthesis and anti-T. cruzi activities of a novel series of phthalimido-thiazoles. Some of these compounds showed potent inhibition of the trypomastigote form of the parasite at low cytotoxicity concentrations in spleen cells, and the resulting structure-activity relationships are discussed. We also showed that phthalimido-thiazoles induced ultrastructural alterations on morphology, flagellum shortening, chromatin condensation, mitochondria swelling, reservosomes alterations and endoplasmic reticulum dilation. Together, these data revealed, for the first time, a novel series of phthalimido-thiazoles-structure-based compounds with potential effects against T. cruzi and lead-like characteristics against Chagas disease.

This work was carried out in collaboration between all authors. Author ALS participated in allexperiments of biological activity as well as the manufacture of writing and discussion of all results of the manuscript. Authors JFDO and ALS assisted in the preparation and correction of written of the manuscript. Author JFO participated in all experiments of biological activity. Author EFS participated in all experiments of biological activity. Author ASAAJ participated in all experiments of biological activity. Author ITTJ participated in all the syntheses for obtaining imidazolidinic derivative. Author CAP participated of experiments of biological activity. Author VPCR participated in experiments of biological activity. Author MBPS participated in experiments of biological activity. Author IRP assisted in the preparation and correction of written. Author MCAL participated in all the syntheses for obtaining imidazolidinic derivative, assisted in the preparation and correction of written and discussion of all results of the manuscript.

Phthalimide, 1,3-thiazole, and thiazolidinone cores are considered privileged scaffolds and represent an attractive starting point to design new bioactive compounds for neglected tropical disease (NTD). Schistosomiasis is a NTD, caused by Schistosoma worms which praziquantel (PZQ) is the only drug used to treat humans, but the decrease in the effect after treatment has been reported. Recently, some phthalimide-thiazole derivatives exhibited in vitro antischistosomal activity against adult worms with significant ultrastructural changes and a lower cytotoxic effect on splenocytes. This new biological phthalimido-thiazole profile has motivated us to evaluate a new generation of such molecules in immature and adult worms. Thus, a phthalimido-thiazolidinone derivative, (3c), and three phthalimido-thiazoles (6c, 7a, and 7h) were evaluated concerning their in vitro activity on schistosomulae and adult worms. The results showed that these compounds brought a significant reduction on the mortality, inhibited oviposition, and then induced mortality in immature and adult worms alike. According to scanning electron microscopy, the tegument was the principal target for 7a and 7h and revealed gradual damage to the tegument surface, inducing destruction and decomposition of the tegument in the same areas and exposition of subtegumental tissue and of muscle tissue. Furthermore, they caused less toxicity in splenocytes than PZQ. Compounds 7a and 7h revealed to possess promising activity against larval forms. According to the present study, the privileged structure phthalimido-thiazoles act as a molecular framework that has antischistosomal activity and most form the basis to the next pre-clinical tests. Graphical abstract.

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DETERMINAÇÃO DAS NECESSIDADES HÍDRICAS DO MELOEIRO PARA DUAS ÉPOCAS DE PLANTIO, NA REGIÃO DO SUBMÉDIO DO VALE DO SÃO FRANCISCO     JEONES MARINHO SIQUEIRA1; GERTUDES MACÁRIO DE OLIVEIRA2; MÁRIO DE MIRANDA VILAS BOAS RAMOS LEITÃO3; EDGO JACKSON PINTO SANTIAGO4 E GABRIELA VIEIRA DE SA SANTOS5.   1Unidade de Estudos e Projetos (UEP), Cia de Desenvolvimento dos Vales do São Francisco e Parnaíba (CODEVASF), Rua Presidente Dutra, 160, Centro, 56304-230, Petrolina, PE, Brasil. E-mail: jeonesmariho@gmail.com, 2Departamento de Tecnologia e Ciências Sociais (DTCS), Av, R. Edgar Chastinet, s/n - São Geraldo, Juazeiro - BA, 48900-000, Juazeiro-BA, Brasil. E-mail: gemoliveira@uneb.br 3Departamento de Engenharia Agrícola e Ambiental, Universidade do Vale do São Francisco (UNIVASF), Av. Antônio C. Magalhães, 510, Country Club, Juazeiro - BA, CEP: 48902-300, Juazeiro-BA, Brasil. E-mail: mario.miranda@univasf.edu.br 4Departamento de Estatística e Informática (DEINFO), Universidade Federal Rural de Pernambuco (UFRPE), Rua Dom Manuel de Medeiros, s/n, Dois Irmãos - CEP: 52171-900 - Recife/PE. edgoj@hotmail.com. 5Departamento de Tecnologia e Ciências Sociais (DTCS), Av, R. Edgar Chastinet, s/n - São Geraldo, Juazeiro - BA, 48900-000, Juazeiro-BA, Brasil. E-mail: gabrielavieira.sa@gmail.com     1 RESUMO   O objetivo deste estudo foi determinar a evapotranspiração da cultura (ETc) e o coeficiente de cultura (Kc) do meloeiro para duas épocas de plantio na região do Submédio do Vale do São Francisco. A pesquisa foi realizada na área experimental com estrutura de evapotranspirômetros de lençol freático constante, da Universidade do Estado da Bahia-UNEB em Juazeiro-BA. Foram realizados dois experimentos, (outubro a dezembro de 2019 e o outro de junho a agosto de 2020). Utilizou-se duas cultivares de melão, a Gladial e a Cantaloupe. O Kc foi determinado com base na ETc, obtidos nos evapotranspirômetros, e na evapotranspiração de referência (ETo) estimada pelo método Penman-Monteith. O consumo hídrico médio das cultivares de melão Gladial e Cantaloupe em 2019 foram respectivamente, 323,5 e 292,0 mm e em 2020 179,7 e 179,3 mm. O Kc foi em média de 0,81 para cv. Gladial e 0,77 para a cv. Cantaloupe (2019) e de 0,68 e 0,66 para as cultivares Gladial e Cantaloupe, respectivamente, em 2020. Diferenças no requerimento hídrico de cultivares de meloeiro estão associadas às características genéticas, condições climáticas e técnicas de cultivo.   Palavras-chave: cucumis melo L, coeficiente de cultura, evapotranspiração da cultura.     SIQUEIRA, J. M.; OLIVEIRA, G. M.; LEITÃO, M. M. V. R.; SANTIAGO, E. J. P.; SANTOS, G. V. S. DETERMINATION THE WATER NEEDS OF MELON FOR TWO PLANTING SEASONS, IN THE SUBMEDIUM REGION OF VALE DO SÃO FRANCISCO         2 ABSTRACT   The objective of this study was to determine crop evapotranspiration (ETc) and crop coefficient (Kc) of melon for two planting times in the Sub-Medium region of the São Francisco Valley. The research was carried out in the experimental area with a constant water table evapotranspirometer structure, at the State University of Bahia-UNEB in Juazeiro-BA. Two experiments were carried out, (October to December 2019 and the other from June to August 2020). Two melon cultivars were used, Gladial and Cantaloupe. Kc was determined based on ETc, obtained from evapotranspirometers, and on reference evapotranspiration (ETo) estimated by the Penman-Monteith method. The average water consumption of Gladial and Cantaloupe melon cultivars in 2019 were, respectively, 323.5 and 292.0 mm, and in 2020, 179.7 and 179.3 mm. Kc averaged 0.81 for hp. Gladial and 0.77 for cv. Cantaloupe (2019) and 0.68 and 0.66 for the Gladial and Cantaloupe cultivars, respectively, in 2020. Differences in the water requirement of melon cultivars are associated with genetic characteristics, climatic conditions and cultivation techniques.   Keywords: cucumis melo L, crop coefficient, culture evapotranspiration.

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Hokin y Hokin mostraron, en 1958, que cuando las fracciones de cerebro se incuban en condiciones óptimas para fosforilización oxidativa, se incorpora ortofosfato radiactivo en algún fosfolípido no identificado. Estos fosfolípidos no identificados se han resuelto por cromatografía en tres manchas definidas; el sistema de cromatografía en papel consiste en papel impregnado de ácido silícico con fenol saturado, con NH3, 0,1 % como disolvente. Estas tres manchas se llamaron fosfolípidos A (Rf, 0,09), B (Rf, 0,030) y C (Rf, 0,51). En el presente trabajo se intentó el estudio de algunas de las propiedades de estos compuestos, y el aislamiento y purificación de uno de ellos, mediante una combinación de técnicas de cromatografía en columna y distribución en contracorriente.