Atividade antiplasmódica e toxicológica de plantas medicinais usadas popularmente no Brasil : uma abordagem etnobotânica

Malaria is a disease of global distribution, recognized by governments around the world as a serious public health problem, affecting more than 109 countries and territories and endangering more than 3.3 billion people. The economic costs of this disease are also relevant: the African continent itself has malaria-related costs of about $ 12 billion annually. Nowadays, in addition to chloroquine, Plasmodium falciparum is resistant to many drugs used in the treatment of malaria, such as amodiaquine, mefloquine, quinine and sulfadoxine-pyrimethamine; resistance of Plasmodium vivax to treatments, although less studied, is also reported. Nature, in general, is responsible for the production of most known organic substances, and the plant kingdom is responsible for the most of the chemical diversity known and reported in the literature. Most medicinal plants commercialized in Brazil, however, are of exotic origin, which makes the search for endemic medicinal plants, besides a patent necessity, a fascinating subject of academic research and development. This study aimed to: (i) verify the antimalarial activity of ethanolic and hydroalcoholic extracts of Boerhavia paniculata Rich. And acetonic extract of Clethra scabra Pers. in Swiss albino mice infected by Plasmodium berghei NK65, (ii) observe possible combined effects between the course of infection by P. berghei NK65 and administration of these extracts in Swiss albino mice, and (iii) conduct a preliminary study of the acute toxicity of these extracts in Swiss albino mice. All extracts notable pharmacological activities - with parasite infections inhibitions ranging from 22% to 54%.These characteristics suggest that the activities are relevant, although comparatively lower than the activity displayed by the positive control group (always above 90%). The general framework of survival analysis demonstrates an overall reduction in survival times for all groups. Necroscopy has not pointed no change in color, shape, size and/or consistency in the evaluated organs - the only exception was the livers of rats submitted to treatment to hydroalcoholic extracts: these organs have been presented in a slightly congestive aspect with mass increasing roughly 28% higher than the other two groups and a p-value of 0.0365. The 250 mg/Kg ethanolic group has been pointed out by the Dunn s post test, as the only class with simultaneous inequalities (p<0.05) between positive and negative control groups. The extracts, notably ethanol extract, have, in fact, a vestigial antimalarial activity, although well below from the ones perceived to chloroquine-treated groups; nevertheless, the survival times of the animals fed with the extracts do not rise by presence of such therapy. Both the toxicopharmacological studies of the synergism between the clinical course of malaria and administration of extracts and the isolated evaluation of toxicity allow us to affirm the absence of toxicity of the extracts at the level of CNS and ANS, as well as their non-influence on food and water consumption patterns, until dosages of 500 mg/Kg. Necroscopic analysis leads us to deduct a possible hepatotoxic effect of hydroalcoholic extract at dosages of 500 mg/Kg, and an innocuous tissue activity of the ethanol extract, in the same dosage. We propose a continuation of the studies of these extracts, with protocol modifications capable of addressing more clearly and objectively their pharmacological and toxicological aspects

Proteínas SAG1, SAG2, SAG3 de toxoplasma gondii como perspectivas para o desenvolvimento de protótipo vacinal contra a toxoplasmose

Toxoplasmosis is a zoonosis of worldwide distribution caused by the protozoan Toxoplasma gondii, triggering dangerous complications in immunocompromised patients and pregnant women, as well as having great economic impact for the livestock. So far the control of toxoplasmosis is made primarily by chemotherapy. However, most drugs used routinely have some limitations. In order to control this disease, several research groups, including ours, has been working to develop a medical-veterinary vaccine based on parasite antigens, vectors and protocols of immunization. In this study were implemented and standardized methodologies for amplification and cloning of recombinant immunogens in the system for the development of a prototype vaccine, based on the surface antigens of T. gondii and recombinant adenovirus encoding these antigens. Genes encoding BAG1, GRA2 and SAG1 proteins were amplified. We established a strategy for cloning SAG1, SAG2, SAG3 and TgAMA1- genes in recombinant system. The genes encoding SAG1 and SAG2 were cloned and their sequences showed high similarity with sequences from GenBank. The virtual translation of these proteins showed polymorphisms in the amino acid sequence, which can be correlated with levels of antigenicity. Simultaneously, the adenovirus encoding the SAGs (HAdSAGs) were expanded, purificated and characterizated. Immunization of C57bl/6 mice, using viral supernatant was not enought to elicit immune responses at high levels, being required HAdSAGs titration for future immunizations. Therefore, this study allowed the cloning of the two genes important for the development of a prototype vaccine. Besides, implementations methodologies that permit advancements in the development of a vaccine against toxoplasmosis using adenovirus to express proteins of the parasite

Leishmania (Viannia) shawi purified antigens confer protection against murine cutaneous leishmaniasis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Protozoan parasites of Xiphophorus spp. (Poeciliidae) and their relation with water characteristics

Investigou-se a relação entre as características da água e a infestação de protozoários parasitos, Icthyophthirius multifiliis e Trichodina sp., em peixe espada, Xiphophorus helleri e em plati, Xiphophorus maculatus, coletados em uma piscicultura de peixes ornamentais no Estado de São Paulo, Brasil. Os peixes foram coletados mensalmente, durante um ano, dos viveiros e das caixas de estocagem. A prevalência da infestação nos peixes das caixas e dos viveiros foram, respectivamente, 34,2% e 22,5% para I. multifiliis e 13% e 54% para Trichodina sp. A elevada condutividade elétrica e o pH da água reduziram a infestação por I. multifiliis. A baixa concentração de oxigênio resultou em aumento na infestação por Trichodina sp. O uso do sal, para aumentar a condutividade elétrica da água, consistiu em um método de controle de I. multifiliis. A redução do oxigênio dissolvido e a adição de fertilizante orgânico favoreceram a reprodução de Trichodina sp.

Alterações nas concentrações das SRAT, conteúdo de GSH e atividade da CAT em pacientes com esquistossomose aguda

Schistosomiasis is an ancient disease caused by helminth Schistosoma mansoni and is a public health problem in Brazil. The granulomatous lesion, typical of the disease, associates itself with increase in the oxidative damage through the generation of free radicals. The aim of this work was to evaluate the occurrence of changes in parameters oxidant / antioxidant that are part of the human defense system, and observe whether they would cause oxidative stress in subjects with schistosomiasis. Moreover, correlating with some biochemical and hematological parameters. Two groups were selected for study, consisting of individuals of both sexes, aged between 16 and 30 years. A control group, formed by individuals without schistosomiasis (n = 30) and a test group, formed by individuals with schistosomiasis (n = 30). The evaluation of lipid peroxidation in plasma was performed by determination of malondialdehyde and antioxidant defense by the quantification of reduced glutathione and catalase activity. For the parameters that assess oxidative stress, the results showed a decrease in the content of reduced glutathione and no change in the activity of catalase, with an increase in the value of malondialdehyde. Therefore, the data found suggest the occurrence of oxidative stress in subjects with schistosomiasis. Of the parameters that assess hepatic function, only levels of aspartate aminotransferase have been high, while there was a decrease of bilirubine. There was a significant change in the lipid profile (p <0.5), however with regard to the renal function of patients, there was a decrease in creatinine. The assessment hematological, made through hemogram and the quantification of hemoglobin, shows increase of eosinophils individuals in the group test, which can be related to the presence of the parasite. The amendments suggest the involvement of oxidative stress in the pathophysiology of this disease

Estudo dos fatores associados à infecção chagásica em área endêmica do Rio Grande do Norte

The Chagas disease is a infectious and parasite disease that has as the causative agent a Trypanosoma cruzi, a protozoan parasite that can be transmitted to humans by the faeces of triatomines ( barbeiros ) in the blood-sucking. To understand the relationship between factors associated with chagasic infection and the risk of transmission of Trypanosoma cruzi, this work aimed to make a correlation between the results of serology, obtained by different immunological techniques, used for diagnosis of Chagas disease and risk factors to which the population of the city of Apodi-RN is exposed, to be considered a endemic area. The case-control study was conducted with 199 individuals, which initially was applied a questionary about socio-economic questions and some risk factors which they were exposed and also favor the spread of disease. Then was given the diagnosis by immunological techniques of serology by indirect hemagglutination, ELISA and indirect immunofluorescence. From the diagnosis, the subjects were divided into case group (presence of infection) and control group (no infection). Regarding the descriptive characteristics of the sample, were found a higher frequency of female individuals (59.3%), between 36 and 50 years of age (36.7%), with low education level (91%) and income monthly up to 1 minimum wage (67.8%). The serology, performed by three techniques of different principles, had a reactivity of 38.9% by Indirect Hemagglutination, 39.7% by ELISA and 38.7% by Indirect Immunofluorescence. As the result of the serology, 71 of samples showed reactivity in 2 or more techniques. On some risk variables, was found a significant relationship between individuals who had been bitten by the triatomines and had positive serology for Chagas disease (93.3%). Other variables of risk revealed individuals who had positive serology and had domestic animal (80.3%), lived in poorly maintained homes (97.2%) and near the forest (84.5%). A better understanding of the dynamics of transmission of T. cruzi and the risk factors that contribute to its occurrence in a region are needed to develop effective strategies for control of Chagas disease in these áreas

Morphologic and morphometric analysis of Hepatozoon spp. (Apicomplexa, Hepatozoidae) of snakes

Hepatozoon species are the most abundant hemoparasites of snakes. Its identification has been based mainly on the morphologic characterization of the gamonts in the peripheral blood of the vertebrate host and also of the cysts found in the internal organs of the vertebrate and invertebrate hosts. Using a computerized image analysis system, we studied five species of Hepatozoon from recently captured snakes in Botucatu, State of São Paulo, Brazil, to evaluate the importance of the morphology and morphometry of the gamonts for the characterization of Hepatozoon species and to analyze the morphologic changes induced in the erythrocytes by the parasite. The studied species were H. terzii of Boa constrictor amarali, Hepatozoon sp. of Crotalus durissusterrificus, H. philodryasi of Philodryas patagoniensis, and H. migonei and H. cyclagrasi of Hydrodynastes gigas. We observed three different groups, one of them including the species H. terzii, H. philodryasi and Hepatozoon sp. of C. durissus terrificus; and the other two consisting of H. migonei and H. cyclagrasi. Degree of alterations in the erythrocytes was variable and it may be useful for characterization of Hepatozoon species.

Soroprevalência da infecção pelo Trypanosoma cruzi no município de Caicó, RN, e caracterização genética por RAPD do parasito isolado de humanos e de triatomíneos no semiárido potiguar

Trypanosoma cruzi infection was evaluated in 390 resident individuals in different rural communities of Caicó municipality, State of Rio Grande do Norte (RN). Of 28 investigated communities the soroprevalence of T. cruzi infection was 2.8% in eight rural communities individuals. The epidemiological characteristics of seropositive shown that the age ranged from 22 to 64 years, being significantly raised from 31 years (90.9%). The female gender was predominant and low education degree. Those individuals reported that they never donated blood, but they had direct contact with triatomines bug. The isolation of the parasite was performed by blood culture and xenoculture methods to determine the genetic variability of the samples. Twenty seven T. cruzi isolates were analyzed by RAPD as genetic marker using three random primers (M13-40, gt11-F and L15996). The T. cruzi isolates showed 73.7% of shared bands considering the average obtained with the three primers, and were genetically well correlated. Using this marker it was possible to separate the populations of the parasite in three distinct groups. The first group composed by isolates obtained of triatomines and humans from four different districts (Caicó, Caraúbas, Serra Negra doNorte and Governador Dix-Sept Rosado); the second contained isolates obtained of triatomines of two different species (T. brasiliensis and P. lutzi) captured in Caraúbas and Serra Negra do Norte. The third grouped isolates obtained from humans of Angicos and Caicó municipalities. In different localities of distinct mesoregions, State of RN, a profile genetic well correlated was identified among all isolates and the presence of three distinct groups of the parasite circulating among vertebrate and invertebrate hosts

An investigation of Leishmania spp. in Didelphis spp. from urban and peri-urban areas in Bauru (São Paulo, Brazil)

Blood and bone marrow samples were taken from 112 Didelphis spp., collected between March 2005 and February 2006, from urban and peri-urban areas of Bauru, São Paulo State, Brazil, to evaluate the hypothesis that these animals might constitute a reservoir of Leishmania spp. Anti-Leishman ia ssp. antibodies were screened in the serum samples using an enzyme-linked immuno-sorbent assay (ELISA) and the polymerase chain reaction (PCR). PCR was performed on fragments of DNA samples from Leishmania spp. using primers 13A and 13B, and showed a positive outcome in 91.6% of the 112 samples tested. of the 107 samples analyzed by ELISA, 71 % were positive. Evidence of epidemiological risk factors such as a circulating parasite and freely moving vectors suggests that Didelphis spp. may participate in the transmission cycle of Leishmania spp. in Bauru. (c) 2007 Elsevier B.V. All rights reserved.

Estudo clínico, cirúrgico e anatomopatológico de intussuscepção em quatro bovinos

Descrevem-se os achados clínico, cirúrgico e anatomopatológico de intussuscepção em quatro bovinos fêmeas. Observaram-se intussuscepção do jejuno, com obstrução total, em três animais, e intussuscepção do cólon, com obstrução parcial, em um animal. A presença de parasitismo intenso por Oesophagostomum sp. em dois animais sugere a participação desse parasita na gênese da intussuscepção.

Detecção de formas amastigotas em exame parasitológico de esfregaço obtido a partir de suabe conjuntival de cães com leishmaniose visceral

Leishmaniose é uma enfermidade multissistêmica cujas manifestações clínicas são extremamente variáveis. em cães sinais clínicos oftálmicos são relativamente frequentes, ainda que outros sinais sistêmicos não sejam identificados. Atualmente, o diagnóstico da doença baseia-se em métodos parasitológicos, sorológicos e moleculares, mas, até o momento, a identificação de formas amastigotas desse parasito em esfregaços feitos a partir de suabes conjuntivais não é empregada rotineiramente. Valendo-se de cães sorologicamente positivos para leishmaniose, portadores (G1) ou não (G2) de alterações oftálmicas, este estudo avaliou a viabilidade do esfregaço a partir de suabe conjuntival como método de diagnóstico para a enfermidade. O exame suprarreferido foi positivo em 60% dos animais do G1 e 38,1% do G2, no entanto não houve diferença estatisticamente significativa em relação à positividade nos dois grupos (P=0,2167). Os dados apontam para uma tendência de os cães com leishmaniose e com sinais oftálmicos serem positivos ao exame parasitológico de esfregaço a partir de suabe conjuntival, podendo esse método ser útil no diagnóstico parasitológico da leishmaniose canina.

Astrocytic and microglial response and histopathological changes in the brain of horses with experimental chronic Trypanosoma evansi infection

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ectoparasitos associados a aves de um fragmento de Floresta Estacional Decidual no Rio Grande do Norte, Brasil

This study to aimed investigate the community of ectoparasites associated with birds in the Mata do Olho D água, in the municipality of Macaíba, Rio Grande do Norte (RN), Brazil, its structure and the ambiental and hosts influential variables on it, and to verify microhabitats preferences by species of chewing lice and feather mites. We examined 172 individuals belonging to 38 species of Passeriformes and non-Passeriformes. 12 new geographic records are reported and 11 host-parasite associations not yet known for chewing lice and feather mites species. Significant relationship was found between the abundance of chewing lice and the variables total length (r = 0.29, p <0.05) and exposed culmen (r = 0.38, p <0.05) of the hosts. A principal component (PC1) accounted for 90.1% of the hosts morphological variation was significantly influential on the abundance of chewing lice (p <0.05), indicating that the morphological characteristics of the hosts may be positively influencing the abundance of these ectoparasites. Significantly higher frequency of individuals with high loads of chewing lice was detected during the dry period (x ² = 8.5, p <0.05), corroborating studies that propose that birds of arid environments suffer as much pressure as those of parasitic humid environments. Analyses of null models of co-occurrence and niche overlap showed a high degree of structure in the feather mites and chewing lice assemblies, when compared with other groups, and preferences in the use of microhabitats by taxa identified. These results corroborate ecological theories in host-parasite systems, contribute to the knowledge of ectoparasites associated with neotropical birds, and the need for experimental studies, as well as further deepening the biology of these arthropods

Efeito de quatro tipos de mel na longevidade e reprodução de Catolaccus grandis (Hymenoptera:pteromalidae)

O trabalho teve como objetivo conhecer o melhor tipo de mel em relação à longevidade e fertilidade do parasitóide do bicudo-do-algodoeiro Catolaccus grandis. Adultos recém-emergidos foram transferidos para recipientes plásticos de 500mL, adaptados com tubo para fornecer água e umidade para os insetos. Um casal do parasitóide foi mantido em cada recipiente em câmara climatizada a 25±1°C, UR = 70±10% e fotoperíodo de 14h. O trabalho constou de 4 tratamentos: mel de flor de laranjeira; mel de flores de plantas silvestres; mel de cana-de-açúcar (todos produzidos por Apis mellifera) e mel de flores silvestres produzido por abelha Jataí (Tetragonistica angustula), com 15 repetições cada. Adultos recém-emergidos do parasitóide receberam cinco larvas de Euscepes postfasciatus encapsuladas em parafilm. Três gotículas de mel foram colocadas sobre o parafilm. Calculou-se a longevidade de machos e fêmeas, número de ovos dia-1 fêmea-1 e número total de ovos fêmea-1 e construíram-se as tabelas de fertilidade. As melhores dietas para alimentar adultos de C. grandis foram o mel silvestre e o de laranjeira. A melhor fecundidade foi observada na dieta de mel de laranjeira (101,60 ovos fêmea-1) e os melhores resultados para aumento reprodutivo e populacional deste parasitóide foram obtidos com mel de laranja e com mel silvestre.

Eficácia do paration metílico e do extrato aquoso de folhas secas de nim no controle de anacanthorus penilabiatus (monogenoidea) em pacu (piaractus mesopotamicus)

This work determined the efficacy of the insecticide methyl parathion and the natural pesticide azadirachtin present in the aqueous extract of dry neem leaves (AEDNL) to Anacanthorus penilabiatus (Monogenoidea) control in pacu (Piaractus mesopotamicus). The efficacy of methyl parathion was evaluated in an experiment consisting of six treatments (0.0, 3.0, 4.0, 5.0, 6.0 and 7.0 mg methyl parathion/L water) and five exposure times (2, 4, 8, 16 and 24 h). The efficacy of azadirachtin present in AEDNL was assessed in an experiment consisting of seven treatments (0,0; 25; 50; 75; 100; 125; e 150 mL/L water) and five exposure times (24, 48, 72, 96 and 120 h). The efficacy of methyl parathion increased with increasing concentration and exposure time. The highest control efficacy was obtained with a concentration of 7 mg methyl parathion/L at all exposure times. In this treatment, the highest efficacies were observed at 16 and 24 h of exposure, with a control rate of 96.2 and 97.0%, respectively. For the AEDNL, the highest control efficacy (89.2%) was obtained with a concentration of 2.9 mg/L after 120 h of exposure. The efficacy in the treatments employing 1.47 and 1.18 mg/L was 83.9 and 82.5%, respectively, after 120 h of exposure. Methyl parathion presented a higher efficacy in the control of A. penilabiatus than the AEDNL. The AEDNL was moderately effective in the control of the parasite.