Cells and mediators of inflammation (C-reactive protein, nitric oxide, platelets and neutrophils) in the acute and convalescent phases of uncomplicated Plasmodium vivax and Plasmodium falciparum infection

The haematological changes and release of soluble mediators, particularly C-reactive protein (CRP) and nitric oxide (NO), during uncomplicated malaria have not been well studied, especially in Brazilian areas in which the disease is endemic. Therefore, the present study examined these factors in acute (day 0) and convalescent phase (day 15) patients infected with Plasmodium falciparum and Plasmodium vivax malaria in the Brazilian Amazon. Haematologic parameters were measured using automated cell counting, CRP levels were measured with ELISA and NO plasma levels were measured by the Griess reaction. Our data indicate that individuals with uncomplicated P. vivax and P. falciparum infection presented similar inflammatory profiles with respect to white blood cells, with high band cell production and a considerable degree of thrombocytopaenia during the acute phase of infection. Higher CRP levels were detected in acute P. vivax infection than in acute P. falciparum infection, while higher NO was detected in patients with acute and convalescent P. falciparum infections. Although changes in these mediators cannot predict malaria infection, the haematological aspects associated with malaria infection, especially the roles of platelets and band cells, need to be investigated further.

Diagnostic reliability of an immunochromatographic test for Chagas disease screening at a primary health care centre in a rural endemic area

Many patients with Chagas disease live in remote communities that lack both equipment and trained personnel to perform a diagnosis by conventional serology (CS). Thus, reliable tests suitable for use under difficult conditions are required. In this study, we evaluated the ability of personnel with and without laboratory skills to perform immunochromatographic (IC) tests to detect Chagas disease at a primary health care centre (PHCC). We examined whole blood samples from 241 patients and serum samples from 238 patients. Then, we calculated the percentage of overall agreement (POA) between the two groups of operators for the sensitivity (S), specificity (Sp) and positive (PPV) and negative (NPV) predictive values of IC tests compared to CS tests. We also evaluated the level of agreement between ELISAs and indirect haemagglutination (IHA) tests. The readings of the IC test results showed 100% agreement (POA = 1). The IC test on whole blood showed the following values: S = 87.3%; Sp = 98.8%; PPV = 96.9% and NPV = 95.9%. Additionally, the IC test on serum displayed the following results: S = 95.7%; Sp = 100%; PPV = 100% and NPV = 98.2%. Using whole blood, the agreement with ELISA was 96.3% and the agreement with IHA was 94.1%. Using serum, the agreement with ELISA was 97.8% and the agreement with IHA was 96.6%. The IC test performance with serum samples was excellent and demonstrated its usefulness in a PHCC with minimal equipment. If the IC test S value and NPV with whole blood are improved, then this test could also be used in areas lacking laboratories or specialised personnel.

Atrazine and picloram adsorption in organic horizon forest samples under laboratory conditions

Adsorption of two herbicides, atrazine and picloram, displaying different sorption characteristics, were evaluated for O (organic) horizon samples collected from SMZs (streamside management zones) in Piedmont (Ultisol) of Georgia, USA. Samples were randomly collected from within 5 SMZs selected for a study of surface flow in field trials. The five SMZs represented five different slope classes, 2, 5, 10, 15 and 20%. Results indicate that 0 horizons have the potential for sorbing atrazine from surface water moving through forested SMZs. Atrazine adsorption was nearly linear over a 24-hour period. Equilibrium adsorption, determined through 24-hour laboratory tests, resulted in a Freundlich coefficient of 67.5 for atrazine. For picloram, negative adsorption was observed in laboratory experiments. This seemed to be due to interference with ELISA analyses; however, this was not confirmed. The adsorption coefficient (Kd) obtained for atrazine in 0 horizons was greater than it would have been expected for mineral soil (from 1 to 4). Picloram was not sorbed in 0 horizons at any significant degree. Although there is a significant potential for the direct adsorption of soluble forms of herbicides in SMZs, the actual value of this adsorption for protecting water is likely to be limited even for relatively strongly sorbed chemicals, such as atrazine, due to relatively slow uptake kinetics.

Role of chemokines in promoting instability of coronary atherosclerotic plaques and the underlying molecular mechanism

Our aim was to investigate the role of chemokines in promoting instability of coronary atherosclerotic plaques and the underlying molecular mechanism. Coronary angiography and intravascular ultrasound (IVUS) were performed in 60 stable angina pectoris (SAP) patients and 60 unstable angina pectoris (UAP) patients. The chemotactic activity of monocytes in the 2 groups of patients was examined in Transwell chambers. High-sensitivity C-reactive protein (hs-CRP), monocyte chemoattractant protein-1 (MCP-1), regulated on activation in normal T-cell expressed and secreted (RANTES), and fractalkine in serum were examined with ELISA kits, and expression of MCP-1, RANTES, and fractalkine mRNA was examined with real-time PCR. In the SAP group, 92 plaques were detected with IVUS. In the UAP group, 96 plaques were detected with IVUS. The plaques in the UAP group were mainly lipid 51.04% (49/96) and the plaques in the SAP group were mainly fibrous 52.17% (48/92). Compared with the SAP group, the plaque burden and vascular remodeling index in the UAP group were significantly greater than in the SAP group (P<0.01). Chemotactic activity and the number of mobile monocytes in the UAP group were significantly greater than in the SAP group (P<0.01). Concentrations of hs-CRP, MCP-1, RANTES, and fractalkine in the serum of the UAP group were significantly higher than in the serum of the SAP group (P<0.05 or P<0.01), and expression of MCP-1, RANTES, and fractalkine mRNA was significantly higher than in the SAP group (P<0.05). MCP-1, RANTES, and fractalkine probably promote instability of coronary atherosclerotic plaque.

Detection of Chlamydia psittaci DNA in avian clinical samples by polymerase chain reaction

A polymerase chain reaction (PCR) assay was developed to detect Chlamydia psittaci DNA in faeces and tissue samples from avian species. Primers were designed to amplify a 264 bp product derived from part of the 5' non-translated region and part of the coding region of the ompA gene which encodes the major outer membrane protein. Amplified sequences were confirmed by Southern hybridization using an internal probe. The sensitivity of the combined assay was found to be between 60 to 600 fg of chlamydial DNA (approximately 6 to 60 genome copies). The specificity of the assay was confirmed since PCR product was not obtained from samples containing several serotypes of C. trachomatis, strains of C. pneumoniae, the type strain of C. pecorum, nor from samples containing microorganisms commonly found in the avian gut flora. In this study, 404 avian faeces and 141 avian tissue samples received by the Central Veterinary Laboratory over a 6 month period were analysed by PCR, antigen detection ELISA and where possible, cell culture isolation. PCR performed favourably compared with ELISA and cell culture, or with ELISA alone. The PCR assay was especially suited to the detection of C. psittaci DNA in avian faeces samples. The test was also useful when applied to tissue samples from small contact birds associated with a case of human psittacosis where ELISA results were negative and chlamydial isolation was a less favourable method due to the need for rapid diagnosis.

Desenvolvimento de uma prova de imunoadsorção enzimática para detecção de anticorpos contra Babesia bovis

Uma prova de imunoadsorção enzimática (ELISA) para detecção de anticorpos contra Babesia bovis foi desenvolvida e avaliada em comparação à imunofluorescência indireta (IFI). A sensibilidade e especificidade do ELISA, determinadas pela análise de 100 soros positivos de bovinos infectados experimentalmente com B. bovis e 108 soros negativos colhidos de bovinos livres de infecção por este hemoparasito, foram de 98,0% e 98,1%, respectivamente. Os valores preditivos positivo e negativo foram, respectivamente, 98,0% e 98,1% e a precisão do teste foi de 98,1%. Não foram detectadas reações cruzadas com 80 soros de bezerros experimentalmente inoculados com Babesia bigemina. O ELISA foi comparado à IFI usando 110 soros de rebanhos de área de estabilidade endêmica e 168 soros de rebanhos de áreas de instabilidade endêmica. em ambos os casos, houve concordância significativa (P=0,631 e 0,4725, respectivamente) entre os resultados demonstrados pelos dois testes. em um estudo epidemiológico realizado com o ELISA na região do Pantanal de Mato Grosso do Sul, com 1.365 soros de bovinos, 83,9% foram positivos para anticorpos contra B. bovis, caracterizando a região estudada como endemicamente estável.

Variabilidade populacional de Plutella xylostella (L., 1758) (Lepidoptera: Plutellidae) e suscetibilidade a Bacillus thuringiensis Berliner

Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV

Investigação de Leishmania spp. em Didelphis spp. (Linnaeus, 1756) na cidade de Bauru-São Paulo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Correlação clínico-laboratorial na amebíase intestinal

O diagnóstico clínico da amebíase intestinal continua sendo meramente presuntivo; o diagnóstico de certeza depende sempre de confirmação laboratorial. Com o objetivo de correlacionar os achados clínicos com a pesquisa do coproantígeno GIAP de Entamoeba histolytica, por teste imunoenzimático, foram estudados 105 pacientes de ambos os sexos, com idade entre 13 e 18 anos, provenientes de demanda passiva do Serviço Ambulatorial de Clínica Médica da Polícia Militar. A prevalência de amebíase intestinal encontrada por coproscopia foi de 13,33% (14/105) e por ELISA 24,76% (26/105). Houve diferença estatisticamente significativa na prevalência desta protozoose quando os métodos foram comparados (p<0,05-McNemar). Entre os enteroparasitas detectados por métodos coproscópicos de rotina destacaram-se: Endolimax nana com 61,90% (65/105), Blastocystis hominis 28,57% (30/105), Entamoeba coli 18,10% (19/105) e Giardia amblia em 5,71 (06/105). Entre os helmintos, os mais prevalentes foram o Trichiuris.trichiura com 4,76% (5/105) e de Ascaris lumbricoides em 3,81% (4,105). A prevalência dessas parasitoses na população estudada foi compatível com a casuística regional. No estudo da sintomatologia dos pacientes com teste de ELISA positivo, 73,08% (19/26) relataram um ou mais sintomas sugestivos de amebíase intestinal, observando-se cólicas intestinais em 46,15% (12/26), diarréia sem elementos anormais em 42,31% (11/26), tenesmo em 3,85% (1/26) e constipação intestinal em 11,54% (3/26). A presença desses sintomas quando comparada com os casos clinicamente idênticos, porém com teste de ELISA não apresentaram significância estatística (p<0,05-McNemar). Quanto a diarréia mucossanguinolenta, esta foi referida por 4,76% de apresentação das síndromes clínicas e sua amplitude de diagnósticos diferenciais, aliados às possibilidades de equívocos que os métodos diagnósticos usualmente empregados podem fornecer. Recomenda-se a inclusão do teste de ELISA no diagnóstico da amebíase intestinal como um recurso indispensável na clínica, embora ele não dispense o exame coproparasitológico, por ser capaz de indetificar somente um patógeno, a E. histolyca.

Níveis de TNF-alfa, IL-4 e IL-10 no baço e no fígado de cães naturalmente infectados por Leishmania (Leishmania) chagasi

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Cyanobacteria, microcystins and cylindrospermopsin in public drinking supply reservoirs of Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Comparative evaluation of several methods for Canine Visceral Leishmaniasis diagnosis

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

Antibody Responses of Vaccinated and Nonvaccinated Calves to Haemophilus somnus

Respiratory disease resulting from infection of calves with Haemophilus somnus (H. somnus) is an annual occurrence in fall calves at the McNay Farm. Previous observations of skin test reactivity to H. somnus antigens suggested a role for this phenomenon in the pathogenesis of the disease. Groups of calves, about 90 days of age, were vaccinated with four different commercial H. somnus vaccines, and serum levels of H. somnus antibodies were determined. Antibodies of the IgG and IgE classes were detected with ELISA procedures conducted on sera collected before and after vaccination. Most of the calves had detectable H. somnus IgE class antibodies at the start of the experimentation but IgG class antibodies were minimal. Antibodies of both classes increased in nonvaccinated and vaccinated calves during the 30 day period of experimentation. However, the level of IgE class antibodies in vaccinates was lower than in controls suggesting that vaccination may limit the IgE response.

Non-sexual household transmission of HCV infection: A cohort study

Objective. This study was designed to determine the prevalence and incidence of HCV infection among non-sexual household contacts of HCV-infected women and to describe the association between HCV infection and potential household risk factors in order to examine whether non-sexual household contact is a route of transmission for HCV infection. ^ Methods. A baseline prevalence survey included 409 non-sexual household contacts of 241 HCV-infected index women in the Houston area from 1994 to 1997. A total of 470 non-sexual household contacts with no evidence of HCV infection at baseline investigation were re-assessed approximately three years after baseline enrollment. Information on potential risk factors was collected through face to face interviews and blood samples were tested for anti-HCV with ELISA-2 and Matrix/RIBA-2. The relationships between HCV infection and potential risk factors were examined by using univariate and multivariate logistic regression analyses. ^ Results. The overall prevalence of anti-HCV positivity among 409 non-sexual household contacts was 4.4%. The highest prevalence of anti-HCV was found in parents (19.5%), followed by siblings (8.1%) and other relatives (5.6%); the children had the lowest prevalence of anti-HCV (1.2%). The univariate analysis showed that IDU, blood transfusion, tattoos, sexual contact with injecting drug users, more than 3 sexual partners in a lifetime, history of a STD, incarceration, previous hepatitis, and contact with hepatitis patients were significantly associated with HCV infection, however, sharing razors, nail clippers, toothbrushes, gum, food or beds with HCV-infected women, and history of dialysis, health care job, body piercing, and homosexual activities were not. Multivariate analysis found that IDU (OR = 221.7 with 95% CI of 22.8 to 2155.7) and history of a STD (OR = 11.7 with 95% CI of 1.2 to 113.1) were the only variables significantly associated with HCV infection. No such associations remained for other risk factors. The three-year cumulative incidence of anti-HCV among 352 non-sexual household contacts of HCV-infected women was zero. ^ Conclusion. This study has provided no evidence that non-sexual household contact is a likely route of transmission for HCV infection. The risk of sharing razors, nail clippers, toothbrushes, gum, food and/or beds with HCV-infected women is not evident and has not been shown to be the likely mode for HCV spread among family members. This study does suggest that IDU is the likely route of transmission for most HCV infection. Association also has been shown independently with a history of STD. The prevalence of anti-HCV among non-sexual household contacts was low. Exposure to common parenteral risk factors and sexual transmission between sexual partners may account for HCV spread among household members of HCV-infected persons. ^

Biotin-avidin sandwich elisa with specific human isotypes IgG1 and IgG4 for Culicidae mosquito blood meal identification from an epizootic yellow fever area in Brazil

With a view toward investigating the feeding behavior of Culicidae mosquitoes from an area of epizootic yellow fever transmission in the municipalities of Garruchos and Santo Antônio das Missões, Rio Grande do Sul State, Brazil, specimens were collected by aspiration from September 2005 to April 2007. The engorged females were submitted to blood meal identification by enzyme-linked immunosorbent assay (ELISA). A total of 142 blood-engorged samples were examined for human or monkey blood through species-specific IgG. Additional tests for specificity utilizing isotypes IgG1 and IgG4 of human monoclonal antibodies showed that only anti-human IgG1 was effective in recognizing blood meals of human origin. The results indicated a significant difference (p = 0.027) in detection patterns in samples of Haemagogus leucocelaenus recorded from human blood meals at Santo Antônio das Missões, which suggests some degree of exposure, since it was an area where epizootic outbreaks have been reported.