Difference in susceptibility to lysis between clones of the Y strain of Trypanosoma cruzi

Three clones isolated from the Y strain of Trypanosoma cruzi - YP1, YP2 and YP3 - were adapted to in vitro cultivation in VERO cells. The recovery of the parasites from the Y strain and clone YP3 was similar after 24 hr of contact with cells (3.2% and 2.7%, respectively) and much lower than the recovery of clones YP1 and YP2 (56.7% and 60.0% of inoculum, respectively). After five days incubation, the ratio Trypomastigotes/Amastigotes released into the supernatants was about 90/10 for clone YP1, YP3 and Y strain, and 50/50 for clone YP2. After nine days, the ratio was 62/38 for clone YP1, 97/3 for clone YP3, 81/19 for Y strain and 50/50 for clone YP2. The susceptibility of tissue culture derived trypomastigotes (TCT) to lysis in the presence of chronic chagasic human sera and human complement was assessed using Complement Mediated Lysis reaction (CML). Trypomastigotes from clone YP2 were consistently less susceptible to CML (% lysis less than 20), than parasites from the other clones and Y strain. Parasites of clone YP3 had susceptibility to CML comparable to that of the Y strain (about 70%), while TCT of clone YP1 had intermediary susceptibility (40%).

Hepatitis B and C prevalences among blood donors in the south region of Brazil

The prevalence of hepatitis B and C infection has been determined in a seroepidemiological survey among blood donors from the south of Brazil (Florianópolis, State of Santa Catarina). These markers has also been correlated with the levels of alanine aminotransferase (ALT), a surrogate marker to prevent post-transfusion hepatitis. Sera from 5000 donors were randomly collected in the period of April to November 1991. The prevalences of HBsAg, anti-HBs and anti-HBc were respectively 0.78, 7.02 and 13.98. The anti-HCV prevalence after confirmation testing with line immunoassay (LIA), was 1.14. Normal values of ALT ( < = 32 U/ml) were found in 59.78, values slightly above the mean (ALT between 32-70 U/ml) in 37.74 and high values of ALT ( > = 70 U/ml) in 2.48. The positivity of anti-HCV antibodies increased with the elevation of ALT levels. This correlation was not observed in relation to HBsAg. There exists a diversity in the recognition of HCV epitopes among HCV positive donors. Via the confirmation test used, we could observe that 94.7 of donors recognize the structural core antigen. Besides that, we observed that 5.26 of the HCV reactive sera recognized only epitopes located in the NS4 and/or NS5 region, indicating the importance of these epitopes for the improvement of assays.

Risk of hepatitis C among brazilian ex-soccer players

In order to evaluate the significance of injecting vitamins complexes and stimulants minutes before soccer games and its role in spread of hepatitis C virus (HCV) we interviewed and tested 40 ex-soccer players, who played professionally in Mato Grosso, Brazil, between 1970 and 1989. Five players were found anti-HCV positive with enzyme-immunoassay. When re-tested by imunoblot (RIBA), three of these five were confirmed to be positive reacting. The anti-HCV positivity (7.5%) was higher than usually found among blood donors (0.9%) in this region (p < 0.01). None of the players had had prior history of any risk factor that might indicate HCV exposure. We suggest that the common practice of soccer players in the inner part of Brazil in the 70's and 80's, to receive fortifying injections, often with shared syringes, may place ex-soccer players in a potencial risk group for HCV infection and warrants further investigation and attention by public health workers.

Prevalence and risk factors of hepatitis C virus infection in hemodialysis patients from one center in Recife, Brazil

A hemodialysis population from a dialysis unit in the city of Recife, Northeastern Brazil, was screened to assess the prevalence of hepatitis C virus (HCV) infection and to investigate the associated risk factors. Hemodialysis patients (n = 250) were interviewed and serum samples tested for anti-HCV antibodies by enzyme-linked immunosorbent assay (ELISA). All samples were also tested for HCV RNA by reverse transcriptase nested polymerase chain reaction (RT-nested-PCR). Out of 250 patients, 21 (8.4%) were found to be seropositive by ELISA, and 19 (7.6%) patients were HCV RNA positive. HCV viraemia was present in 90.5% of the anti-HCV positive patients. The predominant genotype was HCV 1a (8/19), followed by 3a (7/19), and 1b (4/19). None of the anti-HCV negative patients were shown to be viraemic by the PCR. Univariate analysis of risk factors showed that time spent on hemodialysis, the number of blood transfusions and a blood transfusion before November 1993 were associated with HCV positivity. However, multivariate analysis revealed that blood transfusions before November 1993 were significantly associated with HCV infection in this population. Low prevalence levels were encountered in this center, however prospective studies are necessary to confirm these findings.

Attaining the minimum target of resolution WHA 54.19 for schistosomiasis control in the Rainforest Zone of the state of Pernambuco, Northeastern Brazil

Resolution 19 of the 54th World Health Assembly (WHA-54.19) urged member nations to promote preventive measures, ensure treatment and mobilize resources for control of schistosomiasis and soil-transmitted helminthiases (STH). The minimum target is to attend 75% of all school-age children at risk by year 2010. The Brazilian Ministry of Health (MoH) recommends biennial surveys of whole communities and treatment of the positives through the Schistosomiasis Control Program within the Unified Health System (PCE-SUS). However, by 2004 the PCE-SUS had covered only 8.4% of the 1.2 million residents in the Rainforest Zone of Pernambuco (ZMP). Six of the 43 municipalities still remained unattended. Only three of the municipalities already surveyed reached coverage of 25% or more. At least 154 thousand children in the 7-14 years old range have to be examined (and treated if positive) within the next five years to attend the minimum target of the WHA 54.19 for the ZMP. To make this target feasible, it is suggested that from 2006 to 2010 the PCE-SUS actions should be complemented with school-based diagnosis and treatment, involving health and educational organs as well as community associations to include both children in schools and non-enrolled school-age children.

Small intestinal inflammation following oral infection with Toxoplasma gondii does not occur exclusively in C57BL/6 mice: review of 70 reports from the literature

Small intestinal immunopathology following oral infection with tissue cysts of Toxoplasma gondii has been described in C57BL/6 mice. Seven days after infection, mice develop severe small intestinal necrosis and succumb to infection. The immunopathology is mediated by local overproduction of Th1-type cytokines, a so-called "cytokine storm". The immunopathogenesis of this pathology resembles that of inflammatory bowel disease in humans, i.e., Crohn's disease. In this review, we show that the development of intestinal pathology following oral ingestion of T. gondii is not limited to C57BL/6 mice, but frequently occurs in nature. Using a Pubmed search, we identified 70 publications that report the development of gastrointestinal inflammation following infection with T. gondii in 63 animal species. Of these publications, 53 reports are on accidental ingestion of T. gondii in 49 different animal species and 17 reports are on experimental infections in 19 different animal species. Thus, oral infection with T. gondii appears to cause immunopathology in a large number of animal species in addition to mice. This manuscript reviews the common features of small intestinal immunopathology in the animal kingdom and speculates on consequences of this immunopathology for humankind.

Correlation of biological serum markers with the degree of hepatic fibrosis and necroinflammatory activity in hepatitis C and schistosomiasis patients

Liver biopsy is the gold-standard method to stage fibrosis; however, it is an invasive procedure and is potentially dangerous. The main objective of this study was to evaluate biological markers, such as cytokines IL-13, IFN-γ, TNF-α and TGF-β, platelets, bilirubins (Bil), alanine aminotransferase (ALT) and aspartate aminotransferase (AST), total proteins, γ-glutamil transferase (γ-GT) and alkaline phosphatase (AP), that could be used to predict the severity of hepatic fibrosis in schistosomiasis and hepatitis C (HC) as isolated diseases or co-infections. The following patient groups were selected: HC (n = 39), HC/hepatosplenic schistosomiasis (HSS) (n = 19), HSS (n = 22) and a control group (n = 13). ANOVA and ROC curves were used for statistical analysis. P < 0.05 was considered significant. With HC patients we showed that TNF-α (p = 0.020) and AP (p = 0.005) could differentiate mild and severe fibrosis. With regard to necroinflammatory activity, AST (p = 0.002), γ-GT (p = 0.034) and AP (p = 0.001) were the best markers to differentiate mild and severe activity. In HC + HSS patients, total Bil (p = 0.008) was capable of differentiating between mild and severe fibrosis. In conclusion, our study was able to suggest biological markers that are non-invasive candidates to evaluate fibrosis and necroinflammatory activity in HC and HC + HSS.

2D-immunoblotting analysis of Sporothrix schenckii cell wall

We utilized two-dimensional gel electrophoresis and immunoblotting (2D-immunoblotting) with anti-Sporothrix schenckii antibodies to identify antigenic proteins in cell wall preparations obtained from the mycelial and yeast-like morphologies of the fungus. Results showed that a 70-kDa glycoprotein (Gp70) was the major antigen detected in the cell wall of both morphologies and that a 60-kDa glycoprotein was present only in yeast-like cells. In addition to the Gp70, the wall from filament cells showed four proteins with molecular weights of 48, 55, 66 and 67 kDa, some of which exhibited several isoforms. To our knowledge, this is the first 2D-immunoblotting analysis of the S. schenckii cell wall.

Assessment of the treatment of chronic hepatitis C in the state of Mato Grosso, central Brazil

In Brazil, the treatment of hepatitis C virus (HCV) infection is funded by the national public health system (SUS). To evaluate treatment results in the state of Mato Grosso, central Brazil, we have consulted the files of the office of the State Department of Health responsible for supplying such medications. We obtained information on 232 treatments of 201 patients who underwent treatment in or prior to 2008. The study was conducted by reviewing medical records, making telephone calls and interviewing the assistant physicians. Thirty-nine patients (19.4%) had cirrhosis and HCV genotype 1 predominated (64.3%). Excluding patients with comorbidities or treatment without ribavirin we analysed 175 treatments (sustained virologic response occurred in 32.6% of cases). Twenty-six of these 175 were retreatments and the sustained virological response (SVR) rate among them was 30.8%; the SVR rate was 32.9% among those receiving treatment for the first time. The SVR rate of genotype 1 patients was 27.8%, whereas it was 37.5% in non-1 genotype patients. The adjusted multivariate analysis showed association of SVR with the absence of cirrhosis [odds ratio (OR): 7.7; confidence interval (CI) 95%: 2.5, 33.3], the use of pegylated interferon (OR: 5.8; CI 95%: 1.5, 21.4), non-1 genotype (OR: 5.3; CI 95%: 1.7, 16.7) and uninterrupted treatment (OR: 9.0; CI 95%: 3.3, 45.4). The SVR rates were similar to those found in other Brazilian studies about HCV, but lower than those found in national and international clinical trials. These data suggest that the treatments of chronic hepatitis C that are made available by SUS does not, under normal conditions, work as well as the original controlled studies indicated.

Biodistribution of meglumine antimoniate in healthy and Leishmania (Leishmania) infantum chagasi-infected BALB/c mice

Pentavalent antimonials such as meglumine antimoniate (MA) are the primary treatments for leishmaniasis, a complex disease caused by protozoan parasites of the genus Leishmania . Despite over 70 years of clinical use, their mechanisms of action, toxicity and pharmacokinetics have not been fully elucidated. Radiotracer studies performed on animals have the potential to play a major role in pharmaceutical development. The aims of this study were to prepare an antimony radiotracer by neutron irradiation of MA and to determine the biodistribution of MA in healthy and Leishmania (Leishmania) infantum chagasi-infected mice. MA (Glucantime(r)) was neutron irradiated inside the IEA-R1 nuclear reactor, producing two radioisotopes, 122Sb and 124Sb, with high radionuclidic purity and good specific activity. This irradiated compound presented anti-leishmanial activity similar to that of non-irradiated MA in both in vitro and in vivo evaluations. In the biodistribution studies, healthy mice showed higher uptake of antimony in the liver than infected mice and elimination occurred primarily through biliary excretion, with a small proportion of the drug excreted by the kidneys. The serum kinetic curve was bi-exponential, with two compartments: the central compartment and another compartment associated with drug excretion. Radiotracers, which can be easily produced by neutron irradiation, were demonstrated to be an interesting tool for answering several questions regarding antimonial pharmacokinetics and chemotherapy.

Tumour necrosis factor -308 and -238 promoter polymorphisms are predictors of a null virological response in the treatment of Brazilian hepatitis C patients

Certain host single nucleotide polymorphisms (SNPs) affect the likelihood of a sustained virological response (SVR) to treatment in subjects infected with hepatitis C virus (HCV). SNPs in the promoters of interleukin (IL)-10 (-1082 A/G, rs1800896), myxovirus resistance protein 1 (-123 C/A, rs17000900 and -88 G/T, rs2071430) and tumour necrosis factor (TNF) (-308 G/A, rs1800629 and -238 G/A, rs361525) genes and the outcome of PEGylated α-interferon plus ribavirin therapy were investigated. This analysis was performed in 114 Brazilian, HCV genotype 1-infected patients who had a SVR and in 85 non-responders and 64 relapsers. A significantly increased risk of having a null virological response was observed in patients carrying at least one A allele at positions -308 [odds ratios (OR) = 2.58, 95% confidence intervals (CI) = 1.44-4.63, p = 0.001] or -238 (OR = 7.33, 95% CI = 3.59-14.93, p < 0.001) in the TNF promoter. The risk of relapsing was also elevated (-308: OR = 2.87, 95% CI = 1.51-5.44, p = 0.001; -238: OR = 4.20, 95% CI = 1.93-9.10, p < 0.001). Multiple logistic regression of TNF diplotypes showed that patients with at least two copies of the A allele had an even higher risk of having a null virological response (OR = 16.43, 95% CI = 5.70-47.34, p < 0.001) or relapsing (OR = 6.71, 95% CI = 2.18-20.66, p = 0.001). No statistically significant association was found between the other SNPs under study and anti-HCV therapy response.

Comparative biology of Cycloneda sanguinea (Linnaeus, 1763) and Hippodamia convergens Guérin-Méneville, 1842 (Coleoptera, Coccinellidae) focusing on the control of Cinara spp. (Hemiptera, Aphididae)

The giant conifer aphids Cinara pinivora (Wilson, 1919) and Cinara atlantica (Wilson, 1919) (Hemiptera, Aphididae) have been observed attacking Pinus spp. in Southern and Southeastern Brazil. The coccinellids, on the other hand, were found feeding on these aphids in the field, which can be regarded as potential biological control agents. The biological cycle and mortality rate of larvae of Cycloneda sanguinea (Linnaeus, 1763) and Hippodamia convergens Guérin-Méneville, 1842 (Coleoptera, Coccinellidae) were evaluated using twenty larvae of each predator species fed with nymphs of Cinara. The vials with the insects were kept under 15 ºC, 20 ºC and 25 ºC, with 12h photophase and 70 ± 10% relative humidity. The consumption was evaluated every 24 hours and the nymphs replaced. For C. sanguinea, the egg incubation time was 10.5, 5.0 and 4.0 days; the average larval development period was 33.3, 15.8 and 8.6 days and the larval mortality rate 20%,0% and 15%, respectively at 15 ºC, 20 ºC and 25 ºC. For H. convergens, the larval development time was 41.9, 19.3 and 10.9 days at 15 ºC, 20 ºC and 25 ºC, respectively. The larval mortality rate was 35%, 15% and 0% under the three temperatures. Both species developed adequately when fed nymphs of Cinara, however, C. sanguinea performed better than H. convergens, even at 15 ºC, at which temperature the biological cycles of the coccinellids are prolonged, but the temperature is favorable for the development of Cinara populations in the field.

Resposta à temperatura de Aphidius colemani Viereck (Hymenoptera, Braconidae, Aphidiinae) originário de três regiões climáticas de Minas Gerais, Brasil

O parasitóide Aphidius colemani Viereck, 1912 apresenta alta mortalidade em temperaturas constantes superiores a 25°C. Provavelmente esta é a causa do insucesso no controle biológico de Aphis gossypii Glover, 1877 com o uso de A. colemani em temperaturas elevadas em casas de vegetação. Este trabalho teve como objetivo avaliar a resposta a diferentes temperaturas de indivíduos de A. colemani, originários de diferentes regiões climáticas do estado de Minas Gerais. Indivíduos de A. colemani foram coletados nos municípios de Juramento, Lavras e São Gotardo, e criados em laboratório por três gerações em A. gossypii em plantas de pepino, em sala climatizada (22±2°C, 70±10 UR e 12h de fotofase). Uma fêmea de A. colemani, acasalada e com 24-48h de vida, foi liberada por um período de uma hora em uma placa de Petri (15 cm) contendo 20 ninfas de 2° ínstar de A. gossypii em um disco foliar de pepino (4 cm de diâmetro) sobre uma solução ágar/água a 1%. Os pulgões parasitados foram mantidos em câmaras climáticas nas temperaturas de 16, 19, 22, 25 e 28±1ºC, com UR de 70±10% e fotofase de 12h. Nas temperaturas de 16 e 28°C, a emergência dos parasitóides originários de Juramento (65,9 e 35,4%) e São Gotardo (71,4 e 47,6%) foi significativamente inferior àquelas encontradas para os de Lavras (87,1 e 80,9%). A temperatura mais adequada para o desenvolvimento de indivíduos de A. colemani oriundos de Lavras foi mais alta do que para aqueles oriundos de Juramento e São Gotardo. Indivíduos de Lavras apresentaram alta emergência a 28°C, demonstrando a existência de indivíduos de A. colemani com tolerância a temperaturas mais altas. Esses resultados abrem novas perspectivas quanto a possibilidades de utilização de diferentes biótipos de A. colemani no controle biológico de A. gossypii em cultivos protegidos.

Desenvolvimento e exigências térmicas de Orius insidiosus (Say) (Hemiptera, Anthocoridae)

A temperatura exerce grande influência no desenvolvimento dos insetos e o conhecimento desse aspecto é essencial para subsidiar o uso de inimigos naturais como agentes de controle biológico, bem como para a sua criação massal. O presente trabalho teve como objetivo avaliar o efeito de diferentes temperaturas no desenvolvimento de Orius insidiosus (Say, 1832), bem como as suas exigências térmicas. O experimento foi conduzido em câmaras climáticas, a 16, 19, 22, 25, 28 e 31±1°C; UR de 70±10% e fotofase de 12 horas. Como alimento foram utilizados ovos de Anagasta kuehniella (Zeller, 1879). O período embrionário foi de 14,0; 8,9; 6,6; 4,8; 3,9 e 3,3 dias nas temperaturas de 16, 19, 22, 25, 28 e 31°C, respectivamente. Ninfas de todos os instares (independente do sexo que deram origem) foram influenciadas pela temperatura quanto ao seu desenvolvimento, com redução nesse período com o aumento da temperatura. Machos e fêmeas, na temperatura de 25°C, apresentaram um período de desenvolvimento em torno de 12 dias. A temperatura base da fase de ovo foi de 11,78°C e a da fase ninfal foi de 12,27°C e de 13,03°C, para machos e fêmeas, respectivamente. A constante térmica para a fase de ovo foi de 63,75 e para a fase de ninfa de 161,97 e 157,24 graus-dia, para machos e fêmeas, respectivamente. A temperatura de 25°C foi a mais adequada para o desenvolvimento de O. insidiosus.

Descrição dos estágios imaturos e biologia de Chinavia pengue (Rolston) (Hemiptera, Pentatomidae)

Adultos de Chinavia pengue (Rolston, 1983) foram coletados em Garopaba, SC, e criados em laboratório sob condições controladas (24 ± 1°C; UR 70 ± 10%; 12hL:12hE). Como alimento, adultos e ninfas receberam vagens verdes de feijão (Phaseolus vulgaris L.). Os ovos de C. pengue seguem o padrão de coloração e esculturação do cório e coloração e forma dos processos aero-micropilares descrito para as espécies neotropicais de Chinavia. Ninfas de 1º instar possuem uma mancha ovalada no dorso da cabeça e tórax, característica das espécies de Chinavia. Em C. pengue, essa mancha tem coloração laranja-avermelhada, e as manchas abdominais (4+4 manchas laterais e uma mediana) são brancas. Características exclusivas das ninfas de 2º a 5º ínstares de C. pengue são a coloração laranja-avermelhada das manchas do pro- e mesotórax e das manchas circulares no centro das placas abdominais laterais. Não se observou sobreposição nas medidas da largura da cabeça entre os cinco ínstares. Cada fêmea depositou 15,9 ± 4,18 posturas e 218,8 ± 48,60 ovos, sendo 14 ovos/postura o arranjo mais freqüente. A fertilidade foi de 70,0% ± 19,01; a mortalidade no 2º ao 5º estádio foi de 1,6% ± 4,49. A razão sexual obtida foi de 1 macho: 1 fêmea. A duração da fase imatura (ovo a adulto) foi de 45,7 ± 2,99 dias.