Abstract Background: There is still a need for new alternatives in pharmacological therapy for neglected diseases, as the drugs available show high toxicity and parenteral administration. That is the case for the treatment of leishmaniasis, particularly to the cutaneous clinical form of the disease. In this study, we present the synthesis and biological screening of eight 4-phenyl-1,3-thiazol-2-amines assayed against Leishmania amazonensis. Herein we propose that these compounds are good starting points for the search of new antileishmanial drugs by demonstrating some of the structural aspects which could interfere with the observed activity, as well as suggesting potential macromolecular targets. Methods: The compounds were easily synthesized by the methodology of Hantzsch and Weber, had their purities determined by Gas Chromatography-Mass spectrometry and assayed against the promastigote forms of Leishmania amazonensis as well as against two white cell lines (L929 and THP-1) and the monkey's kidney Vero cells. PrestoBlue® and MTT viability assays were the methodologies applied to measure the antileishmanial and cytotoxic activities, respectively. A molecular modeling target fishing study was performed aiming to propose potential macromolecular targets which could explain the observed biological behavior. Results: Four out of the eight compounds tested exhibited important anti-promastigote activity associated with good selectivity indexes when considering Vero cells. For the most promising compound, compound 6, IC50 against promastigotes was 20.78 while SI was 5.69. Compounds 3 (IC50: 46.63 μM; SI: 26.11) and 4 (IC50: 53.12 μM; SI: 4.80) also presented important biological behavior. A target fishing study suggested that S-methyl-5-thioadenosine phosphorylase is a potential target to these compounds, which could be explored to enhance activity and decrease the potential toxic side effects. Conclusions: This study shows that 4-phenyl-1,3-thiazol-2-amines could be good scaffolds to the development of new antileishmanial agents. The S-methyl-5-thioadenosine phosphorylase could be one of the macromolecular targets involved in the action.

A contaminação do solo com fezes de animais mamíferos representa importante fator de risco para a ocorrência de zoonoses, sobretudo a larva migrans visceral e a larva migrans cutânea, causadas por Toxocara spp. e Ancylostoma spp., respectivamente. O presente estudo teve como objetivo verificar a contaminação ambiental por Toxocara spp. e Ancylostoma spp. em amostras de solos coletadas de praças e parques públicos do município de Guarulhos, região metropolitana de São Paulo (São Paulo, Brasil). No período de setembro a dezembro de 2010 as amostras do solo foram coletadas e examinadas pela técnica de centrífugo-flutuação, com dicromato de sódio e sulfato de zinco, e pelo método de Baermann modificado. Dos 47 distritos analisados, 35 (74,5%) estavam contaminadas com ovos de Toxocara spp. e/ou ovos ou larvas de Ancylostoma spp., sendo que a frequencia de Toxocara spp. e Ancylostoma spp. foi de 68,1% e 46,8%, respectivamente. No geral, a Zona Leste de Guarulhos foi a região com maior ocorrência desses parasitas com potencial zoonótico. Em todas as áreas públicas, dos 47 distritos, notou-se a presença de fezes de cães e gatos, assim como animais errantes ou acompanhados de seus proprietários. Faz-se necessário salientar a importância da adoção de medidas de controle reprodutivo de cães e gatos, o tratamento dos animais infectados, assim como medidas educativas para reduzir os riscos de crianças e adultos à exposição desses parasitas causadores de zoonoses

The contaminated soil with mammal feces is an important factor of risk to infection with zoonotic diseases. Amongst these zoonoses are visceral larva migrans and cutaneous larva migrans caused by Toxocara spp. and Ancylostoma spp., respectively. The aim of this study was to assess the environmental contamination by Toxocara spp. eggs and hookworms (Ancylostoma spp.) in public parks and squares in the city of Guarulhos, a metropolitan area of São Paulo, São Paulo State, Brazil. Soil samples were collected, between September and December 2010, and examined using the centrifugal flotation technique with sodium dichromate and zinc sulphate as well as the modified Baermann method. Notably, 35 (74.5%) of the 47 districts surveyed in Guarulhos possessed samples contaminated with Toxocara spp. and/or eggs or larvae of Ancylostoma spp. The frequency of Toxocara spp. and Ancylostoma spp. in the samples from public areas was 68.1% and 46.8%, respectively. Overall, the eastern side of Guarulhos is the region with the highest occurrence of causative agents of larva migrans. In all collection sites, the presence of feces from dogs and cats accompanied by their owners and stray animals were observed. Notably, it is important to adopt measures to control dog and cat breeding, to treat infected animals, and provide health education to the population.

Um total de 909 exemplares de Biomphalaria tenagophila foi coletado de duas regiões em Guarulhos (área Metropolitana de São Paulo, Estado de São Paulo, Brasil) a fim de que fosse verificada infecção por larvas de trematódeos. Em todos os locais de coleta, somente essa espécie foi encontrada e 183 (20,13%) caramujos estavam infectados. Nestes locais, quatro tipos de cercárias foram identificadas com microscópio confocal. Xiphidiocercaria (Cercaria luzti) foi o tipo de cercária mais comum, contribuindo com 76,5% de toda infecção. Cercárias de Schistosoma mansoni foram encontradas, obtendo um total de 13,11%. Strigea cercaria (Cercaria caratinguensis) e Brevifurcate pharyngeate Clinostomatoide cercaria (Cercaria ocellifera) contribuíram com 8,33% e 2,22% de toda infecção, respectivamente. Dupla infecção foi encontrada em doze caramujos, contribuindo com 6,55% de toda infecção. Em todos os locais, pequenos vertebrados foram encontrados e foi observado contato humano com a água. A presença de caramujos infectados por trematódeos que infectam o homem em grandes cidades tem implicações na saúde pública. Deve-se salientar a importância de mais estudos epidemiológicos e biológicos destes parasitas de importância médica e veterinária.

A total of 909 Biomphalaria tenagophila were collected from two areas in Guarulhos (Metropolitan area of São Paulo, São Paulo State, Brazil) to assess larval trematode infections. In all collection sites, only this species was found and 183 (20.13%) harbored trematode infections. In these collections, four morphologically distinguishable types of cercariae were identified by confocal microscopy. Xiphidiocercaria (Cercaria lutzi) was the most common type of cercaria recovered, contributing 76.5% of all infections. Schistosoma mansoni cercariae were recovered and comprised the total of 13.11%. Strigea cercaria (Cercaria caratinguensis) and Brevifurcate pharyngeate Clinostomatoide cercaria (Cercaria ocellifera) contributed 8.33% and 2.22% of all infections, respectively. Double infections (S. mansoni and C. lutzi) were found in twelve snails, contributing 6.55% of all infections. In all sites studied, small vertebrates were found in snail habitats and it was observed human contact with the water. The presence of trematode infected snails in large cities has public health implications. It further provides a starting point for some comprehensive studies on snail-related aspects of transmission and biology of trematode of medical and veterinary importance.

Biomphalaria glabrata (Say, 1818) é um gastrópode pulmonado de água doce que desperta grande interesse médico e veterinário. Bradybaena similaris (Férussac, 1821) é um gastrópode pulmonado terrestre considerado uma praga agrícola de plantações de hortaliças. Ambas as espécies são hospedeiras intermediárias de helmintos. Esses moluscos possuem uma gônada hermafrodita produtora de óvulos e espermatozóides de forma simultânea. Neste estudo foram avaliados aspectos histomorfológicos das gônadas hermafroditas de B. glabrata e B. similaris. A gônada de B. similaris encontra-se subdividida em lobos com glândulas em seu interior, o que não foi observado em B. glabrata. Além disso, em B. similaris as células germinativas estão acumuladas em determinados pontos e com a presença de um ovócito em cada folículo da gônada; não obstante, em B. glabrata as células germinativas encontraram-se justapostas e com mais de um ovócito em cada folículo.

Biomphalaria glabrata (Say, 1818) is a freshwater pulmonate gastropod that represents great medical importance. Bradybaena similaris (Férussac, 1821) is a terrestrial pulmonate gastropod and an important plague to the different plant cultures with economic interest. Both species are intermediate hosts of helminths. These molluscs have hermaphrodites gonads producing eggs and sperm. Here, we examined histoformological aspects of hermaphrodites gonads of both B. glabrata and B. similaris. The gonad of B. similaris is subdivided into lobes and presence of glands in its interior, which was not observed in B. glabrata. Moreover, in B. similaris the germ cells are accumulated in some areas, and has one oocyte in each follicle in the gonad; however, in B. glabrata the germ cells are juxtaposed and more than one oocyte in each follicle.