598 resultados para Lutzomyia (Helcocyrtomyia) peresi
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The kairomone octenol is known as attractive to hematophagous Diptera such as mosquitoes, tsetse flies, and midges. There is little evidence that traps baited with octenol are also effective in attracting phlebotomine sand flies. The present report evaluated octenol in modified Centers for Disease Control and Prevention (CDC) traps in two experiments: 1) modified CDC trap without light and 2) modified CDC trap with light. The traps were baited with octenol at concentrations of 0.5, 27, and 43 mg/h in Rifled() locality, São Paulo, Brazil. Traps without octenol were used as controls. The sand fly Nyssomyia neivai (Pinto) (=Lutzomyia neivai) (Diptera: Psychodidae: Phlebotominae) was the prevalent species (99.9%) in both experiments. The results of the experiments showed that traps baited with octenol at 27 and 43 mg/h caught significantly more N. neivai than control and octenol at 0.5 mg/h with and without light. This is the first report that shows that octenol itself is attractive to N. neivai and associated with light traps significantly increases the catches.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Background: Laboratory studies of host-seeking olfactory behaviour in sandflies have largely been restricted to the American visceral leishmaniasis vector Lutzomyia longipalpis. In comparison, almost nothing is known about the chemical ecology of related species, which transmit American cutaneous leishmaniasis (ACL), due in part to difficulties in raising these insects in the laboratory. Understanding how ACL vectors locate their hosts will be essential to developing new vector control strategies to combat this debilitating disease.Methods: This study examined host-odour seeking behaviour of the ACL vector Nyssomyia neivai (Pinto) (=Lutzomyia neivai) using a wind tunnel olfactometer. The primary aim was to determine whether field-collected female N. neivai would respond to host odours in the laboratory, thereby eliminating the need to maintain colonies of these insects for behavioural experiments. Responses to two key host odour components, 1-octen-3-ol and lactic acid, and a commercially-available mosquito lure (BG-Lure (TM)) were assessed and compared relative to an air control. We also tested whether trials could be conducted outside of the normal evening activity period of N. neivai without impacting on fly behaviour, and whether the same flies could be used to assess baseline responses to air without affecting responses to octenol, thereby reducing the number of flies required for experiments.Results: Octenol was found to both activate host-seeking behaviour and attract female N. neivai in the wind tunnel, while lactic acid elicited weaker responses of activation and attractiveness under identical conditions. The BG-Lure did not activate or attract N. neivai under test conditions. Further experiments showed that sandfly behaviour in the wind tunnel was not affected by time of day, such that experiments need not be restricted to nocturnal hours. Moreover, using the same flies to measure both baseline responses to air and attraction to test compounds did not affect odour-seeking behaviour.Conclusions: The results of this study demonstrate that N. neivai taken from the field are suitable for use in laboratory olfactometer experiments. It is hoped this work will facilitate further research into chemical ecology of this species, and other ACL vectors.
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O presente trabalho relata os aspectos epidemiológicos e clínicos de surto de leishmaniose tegumentar americana na região Sudoeste do estado de São Paulo, área de colonização antiga, não associada a derrubadas de matas. Foram examinados 231 indivíduos, observando-se: a) Sessenta e sete indivíduos (29%) apresentavam leishmaniose confirmada pela histopatologia das lesões cutâneas e intradermorreação de Montenegro. Destes casos, 40 (59,7%) eram homens; b) a idade variou entre 2 (5 casos) e 86 anos (1 caso); c) de acordo com o tipo de lesão, observou-se: 54 (80, 6%) pacientes apresentavam úlceras, 13 (19,4%) nódulos, 4 (5,9%) lesões úlcero-vegetantes e 3 (4,4%) cicatrizes típicas; d) a intradermorreção de Montenegro apresentou 94,7% de positividade nos casos de leishmaniose-doença. Este estudo reforça observações prévias de que, além da forma clássica de transmissão, a leishmaniose pode ser transmitida no intra e peri-domicílio.
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Tuberculosis (TB), a chronic infectious disease, is a major cause of morbidity and mortality worldwide. Expression of iNOS and consequent production of NO during the inflammatory process is an important defense mechanism against TB bacteria. We have tested whether pulmonary TB patients undergoing anti-tuberculosis treatment present DNA damage, and whether this damage is related to oxidative stress, by evaluating total hydrophilic antioxidant capacity and iNOS expression. DNA damage in peripheral blood mononuclear cells from patients and healthy tuberculin test (PPD) positive controls was evaluated by single-cell gel electrophoresis (comet assay), and iNOS expression was measured by qPCR. We also evaluated total hydrophilic antioxidant capacity in plasma from patients and controls. Compared to controls, pulmonary TB patients under treatment presented increased DNA damage, which diminished during treatment. Also, the antioxidant capacity of these individuals was increased at the start of treatment, and reduced during treatment. TB patients showed lower iNOS expression, but expression tended to increase during treatment. Our results indicate that pulmonary TB patients under anti-TB treatment exhibit elevated DNA damage in peripheral blood mononuclear cells. This damage was not related to nitric oxide but may be due to other free radicals. (C) 2012 Elsevier B.V. All rights reserved.
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Leishmania chagasi, which causes visceral leishmaniasis in South America, is an obligate intracellular protozoan. Production of nitric oxide by macrophages during the inflammatory response is one of the main microbicidal mechanisms against this parasite. The goal of this study was to evaluate whether L. chagasi infection causes DNA damage in peripheral blood and spleen cells of Balb/c mice and whether such damage may be related to NO production. Balb/c mice were either infected with L chagasi or maintained as controls. The single-cell gel electrophoresis (comet) assay was used to measure DNA damage in peripheral blood and spleen cells, and the Griess reaction was used to measure NO production in the spleen. L chagasi infection induced DNA damage in peripheral blood and spleen cells of infected mice. Macrophages from the control group, challenged with L. chagasi, showed significantly (p < 0.05) greater NO production, compared to non-challenged cells. Treatment of spleen cells with N(G)-monomethyl-L-arginine (LNMMA) caused a significant reduction of NO production and DNA damage (p < 0.05). Our results indicate that L. chagasi induces DNA damage in the peripheral blood and spleen cells and that NO not only causes killing of the parasite but also induces DNA damage in adjacent cells. (C) 2011 Elsevier B.V. All rights reserved.
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Tuberculosis is still increasing and was declared a worldwide sanitary emergency by the World Health Organization (WHO) in 1995. Its control is difficult due to long treatment duration and lack of markers of treatment success or failure. Cytokines such as IFN-gamma and TNF-alpha, a central factor in immune response against Mycobacterium tuberculosis, are responsible for the interaction between T lymphocytes and the infected macrophage and are also produced during this interaction. As proinflammatory cytokines have a close relationship with mycobacteria clearance, in fact even preceding it, they could be used as markers for inflammatory activity and response to treatment. Proinflammatory cytokines act in the liver and stimulate a strong local and systemic acute-phase response as a result of homeostatic and physiological responses also induced by them. Acute-phase proteins produced by cytokine activity are useful diagnostic markers that could also be used to monitor treatment response as they can be serially quantified. The objective of this study was to evaluate IFN-gamma, TNF-alpha, IL-10 and TGF-beta production in supernatant of peripheral blood mononuclear cell (PBMC) and monocyte (MO) cultures, as well as serum acute-phase response through total protein, albumin, globulin, C-reactive protein (CRP), alpha-1-acid glycoprotein (AGP), and erythrocyte sedimentation rate (ESR) as regression markers of inflammatory response during pulmonary tuberculosis treatment. Twenty blood donors (G1) from the Blood Bank at Botucatu School of Medicine's University Hospital (BSM-UH) were evaluated once and 28 pulmonary tuberculosis patients (G2): 13 from BSM-UH and 15 from the Bauru State Health Secretariat. Patients were evaluated at three moments of treatment: before (M1), at three months (M2), and at the end (M3). Cytokines were determined in 20ml of peripheral blood (ELISA), with or without activation: lipopolysaccharide (LPS) for MO culture and phytohemagglutinin (PHA) for PBMC culture. Acute-phase protein behavior in G2 throughout treatment was: Globulins: M1> M2, M1> M3 (rho < 0.001); CRP: M1> M2> M3 (.< 0.001); AGP for men: M1> M2, M1> M3 (rho < 0.001); ESR for men: M1> M2, M1> M3 (rho < 0.0016) and for women: M1> M2 (.< 0.025). Comparison between cytokine levels found in supernatant of MO and PBMC cultures, with and without stimulus, in G1 and G2 during treatment showed: TNF-alpha (with/ without LPS) at M1: G2> G1; at M2: G2> G1 (rho < 0.001); (without LPS) at M3: G2> G1 (rho < 0.001), (with LPS) at M3: G2> G1 (rho < 0.028); IFN-. (with and without PHA) at M1: G2> G1; at M2: G2> G1 (rho < 0.001); IL-10 (with and without LPS) at M1: G2> G1; at M2: G2> G1; at M3: G2> G1 (rho < 0.001); TGF-beta (with and without LPS) at M1: G2> G1; at M2: G2> G1 (rho < 0.001), (without LPS) at M3: G2> G1 (rho < 0.001). In G2, all cytokines in supernatant of MO and PBMC cultures, with and without stimulus, showed: M1> M2> M3 (rho < 0.01). Levels of globulins, CRP, AGP, and ESR in patients with pulmonary tuberculosis before treatment (M1) were significantly higher than reference values, suggesting their use as diagnostic markers and indicators of treatment. The CRP decreasing values along treatment could be taken as a marker of the regression of inflammatory process and of response to treatment in patients with pulmonary tuberculosis.Regarding cytokines, there was significant increase in TNF-alpha, IFN-gamma, IL-10, and TGF-alpha levels before and at three months treatment, with and without stimulus; in TNF-a and IL-10 lvels, with and without stimulus, as well as in TGF-alpha levels without stimulus at six months. Patients had higher levels of all studied cytokines than controls before treatment, and these values decreased along treatment. In this study, pulmonary tuberculosis patients showed a Th0 cytokine profile before treatment, with the production of both Th1 (IFN-gamma) and Th2 (IL-10) cytokines, in addition to TNF-alpha inflammatory and TGF-alpha regulatory and fibrosis-inducer cytokines. At the end of treatment, all had evolved to Th2 profile, probably in an attempt to reduce the harmful effects of the proinflammatory activity of the Th1 cytokine profile and of the still above-normal levels of TNF-alpha. The high levels of TGF-alpha, also found in these patients, are related to its important role in the extracellular matrix deposition and fibrosis induction that characterize tuberculosis healing process. IFN-gamma was the only cytokine reaching normal levels at the end of treatment, which suggests its use as a marker of response to treatment.
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OBJETIVO: Analisar o padrão de citocinas pró- e antiinflamatórias e da resposta de fase aguda (RFA) como marcadores de resposta ao tratamento da tuberculose pulmonar. MÉTODOS: Determinação dos níveis de interferon-gama (IFN-γ), tumor necrosis factor-alpha (TNF-α, fator de necrose tumoral-alfa), interleucina-10 (IL-10) e transforming growth factor-beta (TGF-β, fator transformador de crescimento-beta), pelo método ELISA, em sobrenadante de cultura de células mononucleares do sangue periférico e monócitos, assim como dos níveis de proteínas totais, albumina, globulinas, alfa-1-glicoproteína ácida (AGA), proteína C reativa (PCR) e velocidade de hemossedimentação (VHS) em 28 doentes com tuberculose pulmonar, em três tempos: antes (T0), aos três meses (T3) e aos seis meses (T6) de tratamento, em relação aos controles saudáveis, em um único tempo. RESULTADOS: Os pacientes apresentaram valores maiores de citocinas e RFA que os controles em T0, com diminuição em T3 e diminuição (TNF-α, IL-10, TGF-β, AGA e VHS) ou normalização (IFN-γ e PCR) em T6. CONCLUSÕES: PCR, AGA e VHS são possíveis marcadores para auxiliar no diagnóstico de tuberculose pulmonar e na indicação de tratamento de indivíduos com baciloscopia negativa; PCR (T0 > T3 > T6 = referência) pode também ser marcador de resposta ao tratamento. Antes do tratamento, o perfil Th0 (IFN-γ, IL-10, TNF-α e TGF-β), indutor de e protetor contra inflamação, prevaleceu nos pacientes; em T6, prevaleceu o perfil Th2 (IL-10, TNF-α e TGF-β), protetor contra efeito nocivo pró-inflamatório do TNF-α ainda presente. O comportamento do IFN-γ (T0 > T3 > T6 = controle) sugere sua utilização como marcador de resposta ao tratamento.
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Despite the existence of highly sensitive tests, inconclusive serological results are frequent in chronic chagasic infection. This study aimed to define a diagnostic conduct for 30 individuals with inconclusive serology (G3) for chagasic infection assisted at the Outpatient Unit for Infectious and Parasitic Diseases of the Botucatu School of Medicine. Twenty-one individuals with negative serology (G1) and 33 with positive serology (G2) were also studied. Serological methods ELISA, HAI, IFI and immunoblotting TESA-cruzi were used for G1, G2 and G3, and parasitological methods xenodiagnosis, hemoculture and PCR-LIT were used for G2 and G3 individuals. ELISA, HAI and IFI were performed in 5 different blood samples in G2 and G3. TESA-cruzi was carried out only once in G1, G2 and G3 and, since it is the most sensitive, it was utilized as standard. In G3, positivity for ELISA reached 86% in the fifth blood sample; the ELISA+HAI+IFI combination showed a maximum of 44.8% in the second sample; and TESA-cruzi, 76% in one single sample. Xenodiagnosis positivity was 9.4%; hemoculture showed 15.2%; and PCR-LIT exhibited 22% positivity in G2. Nevertheless, in G3, positivity percentage was 3.4% for xenodiagnosis, 6.7% for PCR-LIT, and no positive result was found for hemoculture. In G3, PCR-LIT resolved one case which was still inconclusive according to serology tests. In order to define inconclusive diagnoses, the results suggest the combined use of ELISA+HAI+IFI in 2 blood samples, decreasing the occurrence of false positive/negative results. If results remain inconclusive, the performance of TESA-cruzi and PCR-LIT, if necessary, is recommended.
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Toll-like receptors (TLRs) recognise pathogen-derived molecules and influence immunity to control parasite infections. This study aimed to evaluate the mRNA expression of TLRs 2 and 4, the expression and production of the cytokines interleukin (IL)-12, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, IL-17, IL-10 and transforming growth factor (TGF)-β and the production of nitric oxide (NO) in the spleen of mice infected with Leishmania chagasi. It also aimed to evaluate any correlations between mRNA expression TLR2 and 4 and cytokines and NO production. Infection resulted in increased TLR2-4, IL-17, TNF-α and TGF-β mRNA expression during early infection, with decreased expression during late infection correlating with parasite load. IFN-γ and IL-12 mRNA expression decreased at the peak of parasitism. IL-10 mRNA expression increased throughout the entire time period analysed. Although TGF-β, TNF-α and IL-17 were highly produced during the initial phase of infection, IFN-γ and IL-12 exhibited high production during the final phase of infection. IL-10 and NO showed increased production throughout the evaluated time period. In the acute phase of infection, there was a positive correlation between TLR2-4, TNF-α, IL-17, NO, IL-10 and TGF-β expression and parasite load. During the chronic phase of infection, there was a positive correlation between TLR2-4, TNF-α, IL-17 and TGF-β expression and parasite load. Our data suggest that infection by L. chagasi resulted in modulation of TLRs 2 and 4 and cytokines.
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Leishmaniasis is a parasitic zoonosis caused by protozoans of the genus Leishmania transmitted by insects known as phlebotomines, which are found in wild or urban environments. It affects domestic and wild animals and transmission to man happens by accident. The disease occurs in tropical and sub-tropical areas, mainly in Asia, Europe, Africa, and the Americas. There are two forms that affect man: American cutaneous leishmaniasis (ACL) and American visceral leishmaniasis (AVL). The latter is caused by three species of Leishmania: Leishmania (Leishmania) donovani, Leishmania (Leishmania) infantum, and Leishmania (Leishmania) chagasi, which are grouped in the Leishmania (Leishmania) donovani complex. Wild reservoir hosts of L. chagasi known so far are foxes and marsupials. In domestic environment, dogs are the most important reservoir hosts and sources of infection to the vectors Lutzomyia longipalpis. Leishmaniasis is difficult to control, causing epidemic outbreaks, thus being an important public health problem. Due to lesions caused by the mucocutaneous type and the severity of those caused by the visceral type in humans, visceral leishmaniasis is one of the main public health concerns. This paper is part of the monograph presented at the end of the residency program in the field of Zoonosis and Public Health at the School of Veterinary Sciences and Animal Husbandry, São Paulo State University, UNESP, Botucatu, São Paulo State, Brazil, in 2005.
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Background: Leishmaniasis is one of the most important vector-borne diseases of humans. This parasitic disease can be caused by many species of Leishmania. In humans, different species of the parasite are associated with different forms of the disease, cutaneous and visceral. Among domesticated animals, dogs are the most important species in the epidemiology of this disease. Leishmania chagasi, an important zoonosis, is well established as the agent of visceral leishmaniasis in Brazil. The disease is endemic in north, northeast, midwest and southeast, and is transmitted to mammals by hematophagous insects such as the Lutzomyia longipalpis. In 2008, our research group has diagnosed a case of canine leishmaniasis in the municipality of Uruguaiana and subsequently there were several cases in the city and the neighbor municipality of Sao Borja. Most Brazilian states are endemic for leishmaniasis, with the exception of Rio Grande do Sul. In southern Brazil, the reports of humans and dogs infected by Leishmania spp. are the source of endemic area in the country. Therefore, the aim of this study is register the first clinical case of canine visceral leishmaniasis in the municipality of Santa Maria, RS.Case: In october 2010, a veterinary clinic of Santa Maria received a canine, female, Doberman, with two years of age. The animal had severe skin lesions on the head and limbs, pale mucous membranes, and enlarged lymph nodes. According to the owner, the animal showed progressive weight loss and anorexia for more than five days. During the clinical examination the blood was collected for hemogram and cytology of lymph nodes was performed by puncture aspiration with a fine needle. In the erythrogram, it was observed a decrease in the total number of erythrocytes (2.8 x 10(6)/mu L), hematocrit (21%), hemoglobin (6.8 g/dL) and platelets (98 x 10(3)/mu L). In the leucogram, any alteration was observed. The cytology of lymph nodes showed amastigotes forms, suggestive of the Leishmania spp. Based on this finding; we performed the blood collection for PCR, to confirm parasitism and to determine the species of Leishmania. At the molecular test was used PCR-specific for L. chagasi, and the result was positive.Discussion: This is the first autochthonous clinical case in the central region of the RS, non-endemic area for leishmaniasis. In serological studies of visceral leishmaniasis it was diagnosed in five asymptomatic dogs in the municipalities of Santa Maria, Julio de Castilhos and Itaara, however not confirmed by molecular analysis. In the municipalities of Cruz Alta and Uruguaiana cases of L. chagasi have been reported in dogs which previously resided in Leishmania sp. endemic areas. The municipality of Sao Borja had the first record of L. longipalpis in the RS during the leishmaniasis outbreak in 2008-2009. In the central region of the RS vector has not been found, but because in this first autochthonous case dog in Santa Maria believe that the parasite is present and/or doing other insect transmission of leishmaniasis. Clinical signs associated with hematologic and coagulation disorders observed in the canine are commonly described in symptomatic dogs in endemic regions. This case of autochthonous leishmaniasis reinforces the idea of the vector presence in Santa Maria, center of the RS. We believe that canine leishmaniasis is an emerging disease in the southern region of Brazil.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The problem of the classification of the extensions of the Virasoro algebra is discussed. It is shown that all H-reduced G(r)-current algebras belong to one of the following basic algebraic structures: local quadratic W-algebras, rational U-algebras, nonlocal W-algebras, nonlocal quadratic WV-algebras and rational nonlocal UV-algebras. The main new features of the quantum Ir-algebras and their heighest weight representations are demonstrated on the example of the quantum V-3((1,1))-algebra.
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A Leishmaniose Visceral (LV) é causada por protozoários do gênero Leishmania e transmitida por flebotomíneos do gênero Lutzomyia, os quais vêm adaptando-se ao ambiente peridomiciliar, onde o cão é sua principal fonte de alimento, aumentando assim o risco de casos em humanos. Neste trabalho, foram utilizadas técnicas de geoprocessamento e de estastística espacial como contribuição à compreensão da dinâmica epidemiológica da LV na área urbana de Ilha Solteira-SP.