Description of the feeding preferences of triatominae in the Chagas disease surveillance study for the State of Pernambuco, Brazil (Hemiptera: Reduviidae)

Abstract INTRODUCTION: Studying the feeding preferences of triatomines is an important entomological surveillance tool, since continuous surveillance of the disease is necessary. METHODS: The precipitin reaction was used to describe the feeding preferences of triatomines along with their natural infection by flagellates similar to Tyrpanosoma cruzi. Six hundred eighty-seven insects were examined, including Triatoma brasiliensis, Triatoma pseudomaculata, and Panstrongylus lutzi. RESULTS: Sixty-nine (10%) of 687 triatomines examined tested positive for flagellates similar to T. cruzi, and 8 (1.2%) of these fed on human blood. CONCLUSIONS: This study found potential transmitters of Chagas disease both inside and outside the domiciliar environment.

Comparative study of the accuracy of different technique for the laboratory diagnosis of schistosomiasis mansoni in areas of low endemicity in Barra Mansa City, Rio de Janeiro State, Brazil

Schistosomiasis constitutes a major public health problem, with an estimated 200 million people infected worldwide. Many areas of Brazil show low endemicity of schistosomiasis, and the current standard parasitological techniques are not sufficiently sensitive to detect the low-level helminth infections common in areas of low endemicity (ALEs). This study compared the Kato-Katz (KK); Hoffman, Pons, and Janer (HH); enzyme-linked immunosorbent assay- (ELISA-) IgG and ELISA-IgM; indirect immunofluorescence technique (IFT-IgM); and qPCR techniques for schistosomiasis detection in serum and fecal samples, using the circumoval precipitin test (COPT) as reference. An epidemiological survey was conducted in a randomized sample of residents from five neighborhoods of Barra Mansa, RJ, with 610 fecal and 612 serum samples. ELISA-IgM (21.4%) showed the highest positivity and HH and KK techniques were the least sensitive (0.8%). All techniques except qPCR-serum showed high accuracy (82­95.5%), differed significantly from COPT in positivity , and showed poor agreement with COPT. Medium agreement was seen with ELISA-IgG (Kappa = 0.377) and IFA (Kappa = 0.347). Parasitological techniques showed much lower positivity rates than those by other techniques. We suggest the possibility of using a combination of laboratory tools for the diagnosis of schistosomiasis in ALEs.

Evaluation of ‘cattle’ and ‘Indian Bison’ type antigens of Mycobacterium avium subspecies paratuberculosis for diagnosis of Bovine Johne’s Disease using ‘indigenous ELISA’ and AGPT .

Two antigens (‘cattle’ type and ‘Indian Bison’ type) of Mycobacterium avium subspecies paratuberculosis were evaluated for diagnosis of Johne’s disease (JD) in a gaushala (cattle herd). Of the 160 cows of Sahiwal and Hariana breeds screened, 81 (50.6%) tested positive in ELISA and 66 (41.8%) in AGPT test. Using the two antigens, 33.5% tested positive in both the tests while 41.1% tested negative. Exclusively, only 8.2% tested positive in ELISA while 17.1% tested positive in AGPT. Two antigens together detected 58.9% prevalence of MAP in the gaushala. Individually, indigenous ELISA using antigen from native source of MAP proved superior to AGPT in the diagnosis of JD in cows.

Effects of grape powder supplementation on inflammatory and antioxidant markers in hemodialysis patients: A randomized double-blind study / Efeitos da suplementação de farinha de uva sobre marcadores inflamatórios e antioxidantes em pacientes em hemodiálise: Estudo duplo-cego randomizado

Introduction: Polyphenols contained in natural sources such as grapes, have been considered pharmacological agents to combat oxidative stress and inflammation, common features in Chronic Kidney Disease patients. Objective: To evaluate the effects of grape powder supplementation on inflammatory and antioxidant biomarkers in hemodialysis (HD) patients. Methods: The double-blind placebo-controlled randomized clinical trial evaluated non-diabetic HD patients that received grape powder (500 mg of polyphenols/day) (n = 16, 9 men, 53.0 ± 9.8 years of age, 111.6 ± 58.2 HD months) or placebo (n = 16, 9 men, 52.7 ± 13.7 years of age, 110.4 ± 93.1 HD months) for five weeks. The glutathione peroxidase (GSH-Px) activity and C-reactive protein (CRP) levels were evaluated by ELISA method. Results: After the intervention period, the patients receiving grape powder showed an increase in the GSH-Px activity (16.5 (41.0) to 42.0 (43.3) nmol/min/ml) (p < 0.05) and they did not have the CRP levels increased as seen in placebo group (2.6 (0.28) to 2.8 (0.23 mg/L) (p < 0.05). Conclusion: The use of grape powder as phenolic source could play an important role as an antioxidant and anti-inflammatory agent in non-diabetic HD patients. .

Introdução: Polifenóis contidos em fontes naturais, como as uvas, têm sido considerados agentes farmacológicos no combate ao estresse oxidativo e inflamação, condições comuns na Doença Renal Crônica. Objetivo: Avaliar os efeitos da suplementação de farinha de uva sobre marcadores inflamatórios e antioxidantes em pacientes submetidos à hemodiálise (HD). Métodos: Estudo randomizado, duplo-cego, placebocontrolado, no qual foram avaliados pacientes não diabéticos em HD que receberam farinha de uva (500 mg de polifenóis/dia) (n = 16, 9 homens, 53,0 ± 9,8 anos, 111,6 ± 58,2 meses em HD) ou placebo (n = 16, 9 homens, 52,7 ± 13,7 anos, 110,4 ± 93,1 meses em HD) por cinco semanas. A atividade da glutationa peroxidase (GSH-Px) e os níveis plasmáticos de proteína C-reativa (PCR) foram mensurados por meio do método ELISA. Resultados: Após o período de intervenção, os pacientes que receberam farinha de uva apresentaram elevação na atividade da GSH-Px (16,5 (41,0) para 42,0 (43,3) nmol/min/ml) (p < 0,05) e não foi observada elevação nos níveis de PCR, como visto no grupo placebo (2,6 (0,28) para 2,8 (0,23) mg/L) (p < 0,05). Conclusão: O uso da farinha de uva como fonte de polifenóis pode desempenhar um importante papel anti-inflamatório e antioxidante em pacientes não diabéticos submetidos à HD. .

Eclectic feeding behavior of Lutzomyia (Nyssomyia) intermedia (Diptera, Psychodidae, Phlebotominae) in the transmission area of American cutaneous leishmaniasis, state of Paraná, Brazil

Introduction The blood meal source of sandflies provides valuable information about the vector/host interaction and allows for an understanding of American cutaneous leishmaniasis (ACL) transmission mechanisms. The aim of this study was to identify the blood meal sources of Lutzomyia (Nyssomyia) intermedia in an endemic area of leishmaniasis in Brazil's State of Paraná using a precipitin test. Methods Sandflies were collected in the rural locality of Epitácio Pessoa within the City of Adrianópolis, State of Paraná, in southern Brazil. A total of 864 female sandflies were captured, and 862 (99.8%) were identified as L. intermedia species. However, two unidentified specimens were considered to be part of the genus Lutzomyia. Results Among the females examined, 396 specimens presented reactions to a certain type of tested antiserum, and most (67.9%) reacted to the simple type. These sandflies fed mainly on the blood of birds, opossums, and rodents, but specimens that fed on the blood of humans, dogs, horses, cattle, and cats were also found. Among the cross-reactions found (32.1%), bird/rodent, bird/opossum, bird/dog, bird/human, and horse/dog cross-reactions were the most common. Conclusions These results demonstrate a tendency in the eclectic feeding behavior of L. intermedia and support its potential role as a vector for ACL in the study area. .

Análise da fonte alimentar de Panstrongylus megistus (Hemiptera, Reduviidae, Triatominae) e sua atual importância como vetor do Trypanosoma cruzi, no Estado de Minas Gerais / Analysis on the food source of Panstrongylus megistus (Hemiptera, Reduviidae, Triatominae) and its present importance as a vector for Trypanosoma cruzi, in the State of Minas Gerais

INTRODUÇÃO: A pesquisa da fonte alimentar dos triatomíneos auxilia no conhecimento sobre a biologia destes insetos, inclusive para inferir-se a importância dos mesmos como transmissores do Trypanosoma cruzi ao homem. MÉTODOS: O presente estudo objetivou registrar, através da reação de precipitina, a fonte alimentar de triatomíneos provenientes de 54 municípios da região centro-oeste de Minas Gerais, assim como a infecção natural destes para flagelados semelhantes ao Trypanosoma cruzi. RESULTADOS: De julho de 2003 até março de 2007, foram avaliados 416 insetos, todos da espécie Panstrongylus megistus. Somando-se as ocorrências, as aves (70 por cento) e os humanos (22,5 por cento) constituíram as principais fontes sanguíneas. Encontrou-se 16 (3,8 por cento) insetos positivos para flagelados semelhantes ao Trypanosoma cruzi sendo que oito realizaram hematofagia no homem. CONCLUSÕES: Os resultados demonstram necessidade de acentuar a vigilância entomológica na região, visto que foi detectada a possibilidade de ocorrência de novos casos da doença de Chagas através da transmissão vetorial.

INTRODUCTION: Investigation of the food source of triatomines helps in understanding the biology of these insects, and also helps to infer their importance in transmitting Trypanosoma cruzi to humans. METHODS: The present study aimed to use the precipitin reaction to record the food source of triatomines from 54 municipalities in the central-western region of the State of Minas Gerais, as well as their natural infection by flagellates similar to Trypanosoma cruzi. RESULTS: From July 2003 to March 2007, 416 insects were evaluated, all from the species Panstrongylus megistus. Among all these occurrences, birds (70 percent) and humans (22.5 percent) were the major blood sources. Sixteen (3.8 percent) of the insects were found to be positive for flagellates similar to Trypanosoma cruzi, and eight performed hematophagia on humans. CONCLUSIONS: The results show the need to increase the entomological surveillance in this region, given that the possibility of new cases of Chagas disease occurring through vector transmission was detected.

Preferência alimentar de Lutzomyia longipalpis (Lutz & Neiva, 1912) em área de transmissão de leishmaniose visceral em Mato Grosso / Feeding preference of Lutzomyia longipalpis (Lutz & Neiva, 1912) in transmission area of visceral leishmaniasis in Mato Grosso

O estudo dos hábitos alimentares e do conteúdo intestinal dos flebotomíneos permite a identificação dos hospedeiros, indicando os potenciais reservatórios das leishmanias. Este trabalho objetivou determinar a preferência alimentar de Lutzomyia longipalpis e sua relação com a transmissão da leishmaniose visceral. As capturas mensais foram realizadas em área de transmissão de leishmaniose visceral, município de Várzea Grande, Estado de Mato Grosso, no período de janeiro de 2004 a junho de 2006, utilizando-se armadilhas de luz CDC. Foram capturadas 2.376 fêmeas de Lutzomyia longipalpis, das quais 104 (4,4 por cento) estavam ingurgitadas, sendo 32 (30,8 por cento) capturadas no intradomicílio e 72 (69,2 por cento) no peridomicílio. Após reação de precipitina, observou-se que as fêmeas de Lutzomyia longipalpis alimentaram-se preferencialmente em aves (30,8 por cento) e roedores (21,2 por cento), mas também foram encontradas fêmeas alimentadas de sangue de humanos, gambás, bois, cavalos e cães, demonstrando o caráter oportunista da espécie.

Studies on the feeding habits and intestinal content of sandflies make it possible to identify hosts, thereby indicating potential reservoirs for Leishmania. The present study had the aim of determining the feeding preferences of Lutzomyia longipalpis and its relationship with the transmission of visceral leishmaniasis. Specimens were caught every month in a transmission area of visceral leishmaniasis, in the municipality of Várzea Grande, State of Mato Grosso, from January 2004 to June 2006, using CDC light traps. 2,376 females of Lutzomyia longipalpis were caught, of which 104 (4.4 percent) were engorged. Among these, 32 (30.8 percent) were caught inside homes and 72 (69.2 percent) in areas surrounding homes. From the precipitin reaction, it was observed that Lutzomyia longipalpis females fed preferentially on birds (30.8 percent) and rodents (21.2 percent), but they were also found to have fed on blood from humans, opossums, oxen, horses and dogs, thus demonstrating the opportunist nature of this species.

Fuentes de alimentación de panstrongylus herreri (hemiptera: Triatominae) capturados en utcubamba, amazonas - perú / Food sources of panstrongylus herreri (hemiptera: triatominae) collected in utcubamba, Amazonas - Peru

Objetivo. Identificar las fuentes de alimentación de Panstrongylus herreri, procedente del distrito de Cajaruro, provincia de Utcubamba, departamento de Amazonas. Materiales y métodos. El estudio se realizó en dos etapas: primera, se estandarizó la prueba de precipitina usando como antígenos sueros sanguíneos de: humano, perro, gato, cobayo y pollo, y anticuerpos específicos obtenidos por inoculaciónde los antígenos en conejos. Se alimentaron ninfas de Triatoma infestans del IV y V estadio criadas en laboratorio con sangre de perro,cobayo, pollo y humano para luego determinar la sensibilidad y especificidad de la prueba. Segunda, se aplicó la prueba de precipitina a 102ejemplares de P. herreri domiciliarios, procedentes de la zona de estudio. Resultados. Se obtuvo títulos de anticuerpos desde 1:10 000 a1:30 000. La especificidad de la prueba fue 100 por ciento para todos los intervalos de tiempo evaluados; mientras, que la sensibilidad varió de 70 a 100 por ciento. De los 102 P. herreri, en 93 ejemplares se detectó contenido intestinal y se encontró la fuente alimenticia en 77 de ellos, la sangre de cobayo (36,3 por ciento) fue la principal fuente de alimentación, seguido de humano (18,2 por ciento) y pollo (14,3 por ciento). El índice de infección tripano-triatomíno fue 62,4 por ciento. Conclusiones. La prueba de precipitina mostró mejor especificidad que sensibilidad. En las áreas de estudio, la fuente principal de alimentación de P. herreri es la sangre de cobayo, seguido del humano y pollo. El elevado índice de infección a Trypanosoma sp. relacionado con la fuente de alimentación por cobayo, nos indicaría que es el principal reservorio.

Objective. To identify the food sources of Panstrongylus herreri from district of Cajaruro, province of Utcubamba, department of Amazonas. Material and methods. The study was performed in two steps: in the first, a precipitin test was standardized using as antigen, blood sera from human being, dog, cat, guinea pig and chicken and the specific antibodies obtained by inoculation of the antigens in rabbits. Nymphs of Triatoma infestans (IV and V instars)maintained in the laboratory were fed on dog, cat, guinea pig, and human being to determine the sensitivity and the specificity of the precipitin test. In the second step, 102 P. herreri specimens collected from houses of the two villageswere submitted to the standardized precipitin test. Results. The developed test permitted good titles of antibodies in the range from 1:10 000 to 1:30 000. The specificity was 100 per cent and the sensitivity was 70 per cent to 100 per cent. Of the 102 P. herreri specimens were detected intestinal content in 93 and found the food source in 77 of them, the blood of guinea pig (36.3 per cent) was the main source of food, followed by human (18.2 per cent) and chicken (14.3 per cent).The Trypano-triatomine index was 62.4 per cent. Conclusions. The precipitin test showed better specificity than sensitivity. In this study sites, the main food source of P. herreri was guinea pig follow by the human being and chicken. The high rate of insects carrying Trypanosoma sp. was related to the insects fed on guinea pig pointing it out as reservoir of the parasite.

Estudo das fontes alimentares de Panstrongylus lutzi (Neiva & Pinto, 1923) (Hemiptera: Reduviidae: Triatominae) no Estado do Ceará / Feeding sources evaluation of Panstrongylus lutzi (Neiva & Pinto, 1923) (Hemiptera: Reduviidae: Triatominae) in the State of Ceará

Os autores utilizaram a técnica de precipitina para identificar as fontes alimentares de Panstrongylus lutzi (Neiva & Pinto, 1923) em 20 municípios do Estado do Ceará, Brasil. Os resultados detectaram a presença de sangue de oito diferentes fontes sanguíneas e alimentações mistas, demonstrando que Panstrongylus lutzi é uma espécie eclética. Altas taxas de infecção por tripanosomatídeos foram detectadas.

The authors used precipitin technique to detect the feeding sources of Panstrongylus lutzi (Neiva & Pinto, 1923) in 20 municipalities of Ceará State, Brazil. The results detected the presence of blood from eight different blood sources and mixed feedings, demonstrating that Panstrongylus lutzi is an eclectic species. High infection rates for Trypanosoma like-cruzi were detected.

Triatomíneos rupestres infectados por Trypanosomatidae, coletados em Quaraí, Rio Grande do Sul, 2003 / Rupestrian triatomines infected by Trypanosomatidae, collected in Quaraí, Rio Grande do Sul, 2003

Foram capturados triatomíneos rupestres em seis localidades do município de Quaraí-RS, com o intuito de verificar o índice de infeccão por Trypanosomatidae, bem como o animal reservatório. A captura ocorreu no ambiente silvestre, sendo coletados 453 exemplares, os quais foram identificados e separados por estádio ninfal. Coletaram-se 421 (92,9 por cento) exemplares de Triatoma rubrovaria, 26 (5,7 por cento) de Triatoma circummaculata e 6 (1,3 por cento) de Panstrongylus tupynambai. Dentre as três espécies coletadas, somente Triatoma rubrovaria mostrou-se positivo para Trypanosomatidae, num total de 13 (4,2 por cento) exemplares. Após a inoculacão em camundongos e meio de cultura LIT, isolaram-se cinco cepas de Trypanosoma cruzi. Dos triatomíneos infectados com Trypanosomatidae, 4 (30,8 por cento) tiveram a reacão de precipitina não reagente para os anti-soros testados, 4 (30,8 por cento) positivos para anti-soro de roedor, 4 (30,8 por cento) para anti-soro de cabra e 1 (7,7 por cento) para anti-soro de porco e humano.

Passive immunization using purified IgYs against infectious bursal disease of chickens in Pakistan

Infectious bursal disease (IBD) is an acute and highly contagious disease of young chickens caused by Birnavirus. Mortality of infected birds can be best prevented if injected with antibodies. The present study was an attempt to raise specific hyper-immune polyclonal antibodies against IBD virus in Pakistan. Commercial layers divided into four groups were injected with IBD vaccine subcutaneously according to four different treatment regimens. Eggs were collected daily and antibodies were purified from yolk with dextran sulphate. Titers of antibodies in serum and yolk were evaluated with enzyme linked immunosorbant assay and agar gel precipitation test. Antibody titers were significantly higher in yolk than serum. Eggs collected at 28 days post-vaccination had maximum antibody titers. Of treatment regimens, T3 was found to be most effective for hyperimmunization. Lyophilized antibodies stored at 4oC did not lose their activity till the end of experiment. IBD virus infected birds were injected with purified antibodies which induced 92% recovery as compared to control birds. The study implicates that the purified antibodies may be useful as a therapeutic agent to cure IBD infected birds.

Activation of the intrinsic mitochondrial apoptotic pathway in swine influenza virus-mediated cell death

The mitochondrial pathway of swine influenza virus (SIV)-induced apoptosis was investigated using porcine kidney (PK-15) cells, swine testicle (ST) cells, and HeLa cervical carcinoma cells which are known not to support viral replication. As judged by cell morphology, annexin V staining, and DNA fragmentation, PK-15 and ST cells infected with three different subtypes of SIV (H1N1, H3N2, and H1N2) were obviously killed by apoptosis, not necrosis. SIV infection in PK-15 and HeLa cells was shown to decrease the cellular levels of Bcl-2 protein compared to that of mock-infected control cells at 24 h post-infection, whereas expression levels of Bax protein increased in the PK-15 cells, but did not increase in HeLa cells by SIV infection. Cytochrome c upregulation was also observed in cytosolic fractions of the PK-15 and HeLa cells infected with SIV. Apoptosome (a multi-protein complex consisting of cytochrome c, Apaf-1, caspase-9, and ATP) formation was confirmed by immunoprecipitation using cytochrome c antibody. Furthermore, SIV infection increased the cellular levels of TAJ, an activator of the JNK-stressing pathway, and the c-Jun protein in the PK-15 and HeLa cells. Taken together, these results suggest that the mitochondrial pathway should be implicated in the apoptosis of PK-15 cells induced by SIV infection.

The homotrimeric structure of HtrA2 is indispensable for executing its serine protease activity

Serine protease activity of high temperature requrement 2 (HtrA2) is essential for promoting cell death, as well as for protecting against cellular stresses. An X-ray crystallographic study described the formation of a pyramid shaped homotrimer that is a proteolytically competent form of HtrA2; however, little is known about effects of the trimeric structure of HtrA2 on the natural substrates. In this study, we generated the HtrA2 protein that has a single point mutation at the homotrimerization motif to assess relationship between structure and the proteolytic activity of HtrA2 on its substrates. Using gel filtration, a native gel electrophoresis system, and a co-precipitation assay, we confirm that phenylalanine 149 in HtrA2 is a crucial determinant for the formation of the HtrA2 homotrimeric structure. Moreover, we described that the HtrA2 monomeric form abolished not only autoproteolytic activity, but also the proteolytic activity against XIAP (X-linked inhibitor of apoptosis protein) known as the HtrA2 substrate. Taken together, the results indicate that the homotrimeric structure of HtrA2 is required for executing its serine protease activity.

Phospholipase D is activated and phosphorylated by casein kinase-II in human U87 astroglioma cells

Elevated expression of protein casein kinase II (CKII) stimulated basal phospholipase D (PLD) activity as well as PMA-induced PLD activation in human U87 astroglioma cells. Moreover, CKII-selective inhibitor, emodin and apigenin suppressed PMA-induced PLD activation in a dose-dependent manner as well as basal PLD activity, suggesting the involvement of CKII in the activation of both PLD1 and PLD2. CKII was associated with PLD1 and PLD2 in co-transfection experiments. Furthermore, CKII induced serine/threonine phosphorylation of PLD2 in vivo, and the multiple regions of PLD2 were phosphorylated by CKII in vitro kinase assay using glutathione S-transferase-PLD2 fusion protein fragments. Elevated expression of CKII or PLD increased cell proliferation but pretreatment of cells with 1-butanol suppressed CKII-induced cell proliferation. These results suggest that CKII is involved in proliferation of U87 cells at least in part, through stimulation of PLD activity.

Shear stress stimulates phosphorylation of protein kinase A substrate proteins including endothelial nitric oxide synthase in endothelial cells

Fluid shear stress plays a critical role in vascular health and disease. While protein kinase A (PKA) has been implicated in shear-stimulated signaling events in endothelial cells, it remains unclear whether and how PKA is stimulated in response to shear stress. This issue was addressed in the present study by monitoring the phosphorylation of endogenous substrates of PKA. Shear stress stimulated the phosphorylation of cAMP responsive element binding protein (CREB) in a PKA-dependent manner. Western blot analysis using the antibody reactive against the consensus motif of PKA substrates detected two proteins, P135 and P50, whose phosphorylation was increased by shear stress. The phosphorylation of P135 was blocked by a PKA inhibitor, H89, but not by a phosphoinositide 3-kinase inhibitor, wortmannin. Expression of a constitutively active PKA subunit stimulated P135 phosphorylation, supporting the potential of P135 as a PKA substrate. P135 was identified as endothelial nitric oxide synthase (eNOS) by immunoprecipitation study. PKA appeared to mediate shear stress-stimulated eNOS activation. Shear stress stimulated intracellular translocation of PKA activity from 'soluble' to 'particulate' fractions without involving cellular cAMP increase. Taken together, this study suggests that shear stress stimulates PKA-dependent phosphorylation of target proteins including eNOS, probably by enhancing intracellular site-specific interactions between protein kinase and substrates.

Studies on the feeding habits of Lutzomyia ( N. ) intermedia ( Diptera, Psychodidae ), vector of cutaneous leishmaniasis in Brazil

O teste de precipitina foi aplicado na identificação das fontes alimentares de Lutzomyia intermedia, de ambientes intra e peri-domiciliar, do Município de Mesquita, Estado do Rio de Janeiro, Brasil, área de transmissão de Leishmania (V.) braziliensis. Foram testados os seguintes antisoros: homem, ave, cão, eqüino, gambá e roedor. De um total de 370 fêmeas analisadas, revelaram reatividade, contra os antisoros testados, 128 espécimes do intra-domicílio e 59 do ambiente peridomiciliar. A antropofilia de L. intermedia foi confirmada nos dois ambientes trabalhados; da mesma forma, a alimentação deste flebotomíneo em animais domésticos, observada anteriormente em levantamentos entomológicos, foi comprovada pela forte reatividade com antisoros de ave, cão e eqüino. Entretanto, a alimentação em roedores, animais sinantrópicos no ambiente domiciliar (interior e ao redor das residências), é mais uma forte evidência da competência vetorial de L. intermedia, uma vez que roedores sinantrópicos e silvestres são comprovadamente reservatórios de L. (V.) braziliensis.

Aspectos da ecologia e do comportamento de flebotomíneos em área endêmica de leishmaniose visceral, Minas Gerais / Aspects of the ecology and behaviour of phlebotomines in endemic area for visceral leishmaniasis in State of Minas Gerais

O comportamento e hábitos alimentares de algumas espécies da flebotomíneos têm sido útil na compreensão da epidemiologia das leishmanioses. No município de Porteirinha (MG), foram realizadas capturas mensais sistematizadas utilizando-se 28 armadilhas luminosas tipo CDC, durante o período de janeiro a dezembro de 2002. Foram capturadas 14 espécies de flebotomíneos, totalizando 1.408 exemplares. De acordo com o ambiente, os resultados obtidos mostraram que o peridomicílio apresentou a maior (53,3 por cento) porcentagem dos espécimens encontrados na região, embora parte (46,7 por cento) da fauna também tenha sido encontrada no intradomicílio. O repasto sanguíneo de 38 fêmeas de Lutzomyia longipalpis, provenientes do campo, foi identificado através da reação de precipitina. Os resultados indicam que Lutzomyia longipalpis foi a espécie predominante (65,1 por cento), mostrando-se oportunista, podendo sugar uma ampla variedade de vertebrados.

Observações sobre padrões alimentares de mosquitos (Diptera: Culicidae) no Pantanal Mato-Grossense / Observations on feeding patterns among mosquitoes (Diptera: Culicidae) in the Pantanal, MT, Brazil

O hábito alimentar dos culicídeos foi estudado através da técnica de precipitina. As coletas foram realizadas no km 52 da rodovia Transpantaneira (MT-060), a 65km da sede do município de Poconé (MT). Bimestralmente, de dezembro de 2002 a dezembro de 2003, foram realizadas capturas em armadilha Shannon e CDC automática à base de CO2 das 15:00h às 21:00h. Foram utilizados os seguintes anti-soros: ave, roedor, humano, cavalo, boi, capivara e sapo. Das 2.134 fêmeas capturadas, 1.946 (92,2 por cento) foram coletadas em armadilha de Shannon e 188 (8,8 por cento) em armadilha CDC. Desse total, 276 fêmeas (13,0 por cento) estavam ingurgitadas e próprias para o teste de precipitina, sendo 235 (85,1 por cento) coletadas em armadilha de Shannon e 41 (14,9 por cento) em CDC. Verificou-se que 84,2 por cento dos espécimes analisados reagiram para uma fonte alimentar e 15,8 por cento para duas fontes. As espécies Mansonia titillans (Walker), Culex nigripalpus (Theobald), Aedeomyia squamipennis (Theobald) e Psorophora albigenu (Peryassu) foram as mais freqüentes e reagiram para todos os anti-soros. Os anofelinos Anopheles albitarsis (Lynch-Arribalzaga), An. matogrossensis (Lutz & Neiva) e An. triannulatus (Neiva & Pinto), com poucos espécimes, reagiram para cinco anti-soros. As demais espécies apresentaram positividade que variou de três a seis anti-soros. As estimativas do índice alimentar (feeding index) revelaram resultados positivos para oito espécies de culicídeos, destas cinco apresentaram preferência marcante para o hospedeiro capivara.

The feeding habits of culicids were studied by means of the precipitin technique. The collections were made the Trans-Pantanal highway (MT-060- km 52), at 65 km from the main settlement of the municipality of Poconé, MT, every other month, from December 2002 to December 2003. Trapping was performed using Shannon traps and CDC automatic CO2-based traps from 3:00 p.m. to 9:00 p.m. The following antisera were utilized: bird, rodent, human, horse, cattle, capybara and toad. Of the 2,134 females captured, 1,946 (92,2 percent) were collected in Shannon traps and 188 (8,8 percent) in CDC traps. Among these totals, 276 females (13,0 percent) were engorged and suitable for the precipitin test, of which 235 (85,1 percent) were collected in Shannon traps and 41 (14,9 percent) in CDC traps. It was found that 84.2 percent of the specimens analyzed reacted to one food source and 15.8 percent to two sources. Mansonia titillans (Walker), Culex nigripalpus (Theobald), Aedeomyia squamipennis (Lynch-Arribalzaga) and Psorophora albigenu (Peryassu) were the most frequently found species, and reacted to all the antisera. On the other hand, few specimens of the anophelines, Anopheles albitarsis (Lynch-Arribalzaga), An. matogrossensis (Lutz & Neiva) and An. triannulatus (Neiva & Pinto), reacted to five antisera. The other species were positive to three up to six antisera. The estimate of the feeding index revealed positive results for eight species, of these five they presented outstanding preference for the host capybara.

Padronização da técnica imunoenzimática do ELISA de captura, no sistema avidina-biotina para a identificação de sangue ingerido por Lutzomyia (Lutzomyia) longipalpis (Lutz & Neiva, 1912) / Enzyme-linked Immunosorbent Assay biotin/avidin method standardization, for identification of Lutzomyia (Lutzomyia) longipalpis bloodmeals (Lutz & Neiva, 1912)

A identificação de sangue ingerido pelos insetos é um importante parâmetro para elucidar aspectos ligados à transmissão de zoonoses, dentre elas, as leishmanioses. Dos métodos empregados para esclarecer a atração de vetores por animais que possam atuar como reservatórios dessas parasitoses, destacam-se os imunológicos. O estudo teve como objetivo, padronizar a técnica imunoenzimática de captura e titular amostras de sangue ingerido em fêmeas de flebotomíneos ingurgitadas de Lutzomyia longipalpis criadas em laboratório e alimentadas experimentalmente em rato. Em vista da alta sensibilidade, favorecida pelo sistema avidina-biotina, foi possível a realização de pelo menos noventa testes, de cada uma das amostras em duplicata, e constatar a presença de sangue para todas as amostras com períodos de 12 e 24 horas pós-ingestão, observando-se diferença significativa entre os respectivos títulos.

Presence of autoantibodies against HeLa small nuclear ribonucleoproteins in chagasic and non-chagasic cardiac patients

We detected anti-human small nuclear ribonucleoprotein (snRNP) autoantibodies in chagasic patients by different immunological methods using HeLa snRNPs. ELISA with Trypanosoma cruzi total lysate antigen or HeLa human U small nuclear ribonucleoproteins (UsnRNPs) followed by incubation with sera from chronic chagasic and non-chagasic cardiac patients was used to screen and compare serum reactivity. Western blot analysis using a T. cruzi total cell extract was also performed in order to select some sera for Western blot and immunoprecipitation assays with HeLa nuclear extract. ELISA showed that 73 and 95 percent of chronic chagasic sera reacted with HeLa UsnRNPs and T. cruzi antigens, respectively. The Western blot assay demonstrated that non-chagasic cardiac sera reacted with high molecular weight proteins present in T. cruzi total extract, probably explaining the 31 percent reactivity found by ELISA. However, these sera reacted weakly with HeLa UsnRNPs, in contrast to the chagasic sera, which showed autoantibodies with human Sm (from Stefanie Smith, the first patient in whom this activity was identified) proteins (B/B', D1, D2, D3, E, F, and G UsnRNP). Immunoprecipitation reactions using HeLa nuclear extracts confirmed the reactivity of chagasic sera and human UsnRNA/RNPs, while the other sera reacted weakly only with U1snRNP. These findings agree with previously reported data, thus supporting the idea of the presence of autoimmune antibodies in chagasic patients. Interestingly, non-chagasic cardiac sera also showed reactivity with T. cruzi antigen and HeLa UsnRNPs, which suggests that individuals with heart disease of unknown etiology may develop autoimmune antibodies at any time. The detection of UsnRNP autoantibodies in chagasic patients might contribute to our understanding of how they develop upon initial T. cruzi infection.