Pouco é sabido sobre o potencial patogênico de Blastocystis sp. em modelos experimentais. Neste trabalho a patogenicidade desse parasito para o trato gastrointestinal de camundongos Swiss machos foi avaliada de acordo com o inóculo e tempo de infecção. Os animais foram infectados, via intragástrica, com 100, 500, 1.000, 5.000 e 10.000 formas vacuolares de Blastocystis sp. obtidos a partir de uma mistura de oito isolados humanos cultivados axenicamente em meio Jones. Após 7, 14, 21, 28 e 60 dias de infecção os animais foram sacrificados e fragmentos do intestino delgado (duodeno), grosso e ceco foram retirados para análise histopatológica. Blastocystis sp. desencadeou resposta inflamatória nos diferentes tecidos analisados, com predominância de infiltrado mononuclear. No ceco o parasito foi encontrado na túnica muscular mostrando seu caráter invasivo. Inóculos maiores desencadearam processos inflamatórios mais precocemente (7 dias) e inóculos menores mais tardiamente (a partir de 21 dias). Conclui-se que no modelo proposto a patogenicidade dos isolados de Blastocystis sp. estudados tem relação com o inóculo e tempo de infecção.

The pathogenic potential of Blastocystis sp. in experimental models requires further investigation. In this work, the pathogenicity of this parasite in the gastrointestinal tract of male Swiss mice was evaluated according to the inoculum size and period of infection. Animals were infected intragastrically, with 100, 500, 1,000, 5,000 and 10,000 Blastocystis sp. vacuolar forms obtained from a mixture of eight human isolates cultured axenically in Jones' medium. After seven, 14, 21, 28 and 60 days of infection, the animals were sacrificed and fragments of the small intestine (duodenum), large intestine, and cecum were subjected to histopathological analysis. Blastocystis sp. triggered an inflammatory response in the different tissues analyzed, with a predominance of mononuclear cells. The parasite was found in the muscular layer of the cecum, showing its invasive character. Larger inocula triggered inflammatory processes earlier (seven days) than smaller ones (from 21 days). We conclude that, in the proposed model, the pathogenicity of Blastocystis sp. isolates that were studied is related to inoculum size and period of infection.

Definir um modelo experimental de avaliação de alterações quantitativas e morfométricas nos neurônios mientéricos do cólon de camundongos infectados pelo Trypanosoma cruzi. Vinte e oito camundongos Swiss machos foram distribuídos nos grupos: controle (GC, n=9) e infectados com 100 (IG100, n=9) e 1000 (IG1000, n=10) tripomastigotas sanguíneos, cepa Y-T. cruzi II. A parasitemia foi avaliada 3-25 dias pós inoculação (dpi), com pico de parasitos de 7,7 × 10(6) e 8,4 × 10(6) tripomastigotas/mL no 8º dpi (p>0,05) em IG100 e IG1000, respectivamente. A fase crônica da infecção foi obtida com duas doses de 100mg/Kg/weight e uma dose de 250mg/Kg/ weight do benznidazol, em 11, 16 e 18 dpi. Três animais de cada grupo foram sacrificados aos 18, 30 e 75 dpi. O cólon foi corado com Giemsa. A análise quantitativa e morfométrica de neurônios revelou que a infecção causou uma diminuição da densidade neuronal no 30º dpi (p<0,05) e 75 dpi (p<0,05) em IG100 e IG1000. A infecção causou morte e hipertrofia neuronal no 75º dpi em IG100 e IG1000 (p<0,05, p<0,01). As alterações observadas nos neurônios mientéricos foram diretamente relacionadas ao inóculo e tempo de infecção

Define an experimental model by evaluating quantitative and morphometric changes in myenteric neurons of the colon of mice infected with Trypanosoma cruzi. Twenty-eight Swiss male mice were distributed into groups: control (CG, n=9) and inoculated with 100 (IG100, n=9) and 1000 (IG1000, n=10) blood trypomastigotes, Y strain-T. cruzi II. Parasitemia was evaluated from 3-25 days post inoculation (dpi) with parasites peak of 7.7 × 10(6) and 8.4 × 10(6) trypomastigotes/mL at 8th dpi (p>0.05) in IG100 and IG1000, respectively. Chronic phase of the infection was obtained with two doses of 100mg/Kg/weight and one dose of 250mg/Kg/weight of Benznidazole on 11, 16 and 18 dpi. Three animals from each group were euthanized at 18, 30 and 75 dpi. The colon was stained with Giemsa. The quantitative and morphometric analysis of neurons revealed that the infection caused a decrease of neuronal density on 30th dpi (p<0.05) and 75 dpi (p<0.05) in IG100 and IG1000. Infection caused death and neuronal hypertrophy in the 75th dpi in IG100 and IG1000 (p<0.05, p<0.01). The changes observed in myenteric neurons were directly related to the inoculate and the time of infection

A falta de métodos de diagnóstico laboratorial específico e sintomas específicos fazem da toxocaríase uma doença negligenciada nos serviços públicos de saúde. Este estudo teve por objetivo determinar a freqüência de infecção por Toxocara spp. em crianças atendidas no serviço público do Hospital Municipal de Maringá, sul do Brasil, e avaliar a associação com dados epidemiológicos e clínicos, em estudo observacional e transversal. De 14.690 crianças/ano atendidas, com idade entre sete meses a 12 anos, foram coletados 450 soros de setembro/2004 a setembro/2005. Um questionário foi utilizado para avaliar dados epidemiológicos, clínicos e hematológicos. Pelo teste ELISA, com antígeno de excreção/secreção de larvas de Toxocara canis, detectou-se 130 (28,8%) soros positivos, principalmente em crianças entre sete meses e cinco anos (p = 0,0016). Houve significante correlação entre sorologia positiva para Toxocara e freqüente recreação das crianças em caixas de areia da escola ou pré escola (p = 0,011) e presença do gato no domicilio (p = 0,056). Das famílias dessas crianças, 50% possuíam cachorros e o quintal com solo exposto. Eosinofilia (p = 0,776), sinais e sintomas (febre p = 0,992, pneumonia p = 0,289, resfriado p = 0,277, tosse p = 0,783, problema gastrointestinal p = 0877, dor de cabeça p = 0,979, dor abdominal p = 0,965, dores articulares p = 0,686, urticária p = 0,105) não se correlacionaram com a soropositividade. Todavia, duas crianças asmáticas apresentaram títulos de 1:10.240 (> 1:320) e acentuada eosinofilia (p = 0.0001). Os autores enfatizam a necessidade de atividades preventivas.

The lack of specific laboratorial diagnosis methods and precise symptoms makes the toxocariasis a neglected disease in Public Health Services. This study aims to determine the frequency of Toxocara spp. infection in children attended by the Health Public Service of Hospital Municipal de Maringá, South Brazil. To evaluate the association of epidemiological and clinical data, an observational and cross-section study was carried out. From 14,690 attended children/year aged from seven month to 12 years old, 450 serum samples were randomly collected from September/2004 to September/2005. A questionnaire was used to evaluate epidemiological, clinical and hematological data. An ELISA using Toxocara canis larval excretory-secretory products as antigen detected 130 (28.8%) positive sera, mainly between children from seven month to five years old (p = 0.0016). Significant correlation was observed between positive serology for Toxocara, and frequent playing in sandbox at school or daycare center (p = 0.011) and the presence of a cat at home (p = 0.056). From the families, 50% were dog owners which exposed soil backyards. Eosinophilia (p = 0.776), and signs and symptoms analyzed (fever p = 0.992, pneumonia p = 0.289, cold-like symptoms p = 0.277, cough p = 0.783, gastrointestinal problems p = 0.877, migraine p = 0.979, abdominal pain p = 0.965, joint pain p = 0.686 and skin rash p = 0.105) could not be related to the presence of anti-Toxocara antibodies. Therefore, two asthmatics children showed titles of 1:10,240 and accentuated eosinophilia (p = 0.0001). The authors emphasize the needs of prevention activities.

Realizou-se inquérito sorológico e epidemiológico para cisticercose em indivíduos de cinco municípios da região Norte do Estado do Paraná, Brasil. De 2.180 indivíduos investigados através da reação de imunofluorescência indireta, 69 (3,2%) apresentaram títulos significativos de anticorpos anti-Cysticercus cellulosae. Os percentuais de indivíduos com títulos significativos encontrados em Sarandi (6,6%) e Marialva (4,7%) não diferem estatisticamente (Z=1.319, P=0,0936), mas diferem dos percentuais encontrados em Mandaguaçu, Paiçandu e Maringá (P<0,01). Destes indivíduos, 47,9% estavam na faixa etária de 21 a 49 anos e 79,4% eram do sexo feminino. Foi comum o relato de queixas como "dores de cabeça" (70,6%), "tonturas" (57,4%) e "convulsões" (7,4%), além de história de teníase (22,1%) e hábitos de ingestão de carne crua bovina (41,2%) ou suína (27,9%) e carne com "canjiquinha" (25,0%).

An epidemiological and serological study was carried out on a sample of 2,180 individuals, in five counties in the north of Paraná State - Brazil, using the indirect immunofluorescence test to detect anti-Cysticercus cellulosae antibodies. These individuals, 69 (3.2%) showed significant titers of antibodies. No single significant difference between the proportion of reactivity in Sarandi (6.6%) and in Marialva (4.7%) was observed (Z=1,319, P=0,0936), but it was significantly higher than that observed in Mandaguaçu, Paiçandu and Maringá (P<0.01). Of these individuals, 47.9% were within 21-49 years old and 79.4% were of female sex. "Headache" (70.6%), "faintness" (57.4%), and "convulsions" (7.4%) were among the most frequent by reported, moreover, cases of Taenia infections (22.1%) and the custom of eating uncooked beef (41.2%) or pork (27.9%) and meat containing cysticerci (25.0%) were also related.

Realizou-se inquérito sorológico e epidemiológico para cisticercose em indivíduos de cinco municípios da região Norte do Estado do Paraná, Brasil. De 2.180 indivíduos investigados através da reação de imunofluorescência indireta, 69 (3,2%) apresentaram títulos significativos de anticorpos anti-Cysticercus cellulosae. Os percentuais de indivíduos com títulos significativos encontrados em Sarandi (6,6%) e Marialva (4,7%) não diferem estatisticamente (Z=1.319, P=0,0936), mas diferem dos percentuais encontrados em Mandaguaçu, Paiçandu e Maringá (P<0,01). Destes indivíduos, 47,9% estavam na faixa etária de 21 a 49 anos e 79,4% eram do sexo feminino. Foi comum o relato de queixas como "dores de cabeça" (70,6%), "tonturas" (57,4%) e "convulsões" (7,4%), além de história de teníase (22,1%) e hábitos de ingestão de carne crua bovina (41,2%) ou suína (27,9%) e carne com "canjiquinha" (25,0%).

An epidemiological and serological study was carried out on a sample of 2,180 individuals, in five counties in the north of Paraná State - Brazil, using the indirect immunofluorescence test to detect anti-Cysticercus cellulosae antibodies. These individuals, 69 (3.2%) showed significant titers of antibodies. No single significant difference between the proportion of reactivity in Sarandi (6.6%) and in Marialva (4.7%) was observed (Z=1,319, P=0,0936), but it was significantly higher than that observed in Mandaguaçu, Paiçandu and Maringá (P<0.01). Of these individuals, 47.9% were within 21-49 years old and 79.4% were of female sex. "Headache" (70.6%), "faintness" (57.4%), and "convulsions" (7.4%) were among the most frequent by reported, moreover, cases of Taenia infections (22.1%) and the custom of eating uncooked beef (41.2%) or pork (27.9%) and meat containing cysticerci (25.0%) were also related.

Four Trypanosoma cruzi strains from zymodermes A, B, C and D were successively clonedon BHI-LIT-agar-blood BLAB). Twenty clones from the first generation (F1), 10 from The second (F2) and 4 from the third (F3) from the strains A138, B147 and C23 were isolated. The D150 strain provied 29 F1 and F2 clones. The strains and clones had their isoenzyme and K-DNA patterns determined. The clones from A138, Bl47 and C231 strains presented isoemzyme and K-DNA patterns identical between thewmselves and their respective parental strains. Therefore showing the homogenety and stability of isoenzyme and K-DNA patterns after successive cloning. The Dl50 strain from zymodeme D (ZD) showed heterogeneity. Twenty-eight out of 29 clones of the first generation were of zymodeme A and only one was of zymodeme C, confirming previous reports that ZD strains consisted of ZA and ZC parasite populations. The only D150 strain clone of zymodeme C showed a K-DNA pattern identical to its parental strain. The remining clones although similar among themselves were different from the parental strain. Thus the T. cruzi strains had either homonogeneus or heterogeneous populations. The clones produced by successive cloning provided genetically homonogeous populations. Their experimental use will make future results more reliable and reproducible.