TÉCNICAS BIOMOLECULARES APLICADAS EM HOSPEDEIROS INTERMEDIÁRIOS DA ESQUISTOSSOMOSE

Schistosomiasis is a parasitic disease that affects millions of people worldwide. This parasitosis is transmitted by snails that serve as intermediate hosts for digenetic helminths. The correct identification of the transmitting species can help in the epidemiological knowledge of the disease. However, conventional methods of classification may present questionable results due to intraspecific variation between specimens. As a result, this review aimed to describe the main molecular techniques that can be applied, as well as describe the improvement of the methods over time. PCR is a technique developed through the polymerization of DNA strands carried out in vitro, where it amplifies the DNA in multiple copies by enzymatic replication, without needing a living organism. In real-time PCR, amplification, detection and quantification phases are fully automated, occurring simultaneousl. The evolution of the conventional technique resulted in the advent of Protein C Reactive - Restriction Fragment Length Polymorphism (PCR-RFLP), microsatellites, and Protein C Reactive – Random Amplification of Polymorphic DNA (PCR-RAPD). Through these variants it was possible to accurately classify the transmitting species, perform the analysis of intraspecific genetic variability and expand the phylogenetic studies of the populations. Knowledge of the application of molecular techniques can assist in research related to the epidemiology and population control of these vectors that transmit schistosomiasis mansoni.A esquistossomose é uma doença parasitária acometida por milhões de pessoas no mundo. Essa parasitose é transmitida por caramujos que servem de hospedeiros intermediários de helmintos digenéticos. A identificação correta das espécies transmissoras pode auxiliar no conhecimento epidemiológico da doença. Contudo, métodos convencionais de classificação podem ter resultado duvidoso, devido à variação intraespecífica entre os espécimes. Em virtude disso, esta revisão teve como objetivo descrever as principais técnicas moleculares que podem ser aplicadas, assim como o aprimoramento dos métodos ao longo do tempo. A PCR é uma técnica desenvolvida através da polimerização de DNA em cadeia realizada in vitro, onde se amplifica o DNA em múltiplas cópias, por replicação enzimática, sem necessidade de um organismo vivo. Na PCR, em tempo real, as fases de amplificação, detecção e quantificação são totalmente automatizadas, ocorrendo em simultâneo. Com a evolução da técnica convencional, foi surgindo a Proteína C Reativa – Polimorfismo de Comprimento de Fragmento de Restrição (PCR-RFLP), os microssatélites, e a PCR-RAPD. Através dessas variantes foi possível classificar, com precisão, as espécies transmissoras, fazer as análises da variabilidade genética intraespecífica e ampliar os estudos filogenéticos das populações. O conhecimento da aplicação de técnicas moleculares pode auxiliar em pesquisas relacionadas à epidemiologia e ao controle populacional dos vetores transmissores da esquistossomose mansônica

The performance of serological tests for Leishmania infantum infection screening in dogs depends on the prevalence of the disease

Dogs are considered the main reservoir of Leishmania infantum. This protozoan causes visceral leishmaniasis (VL), an uncontrolled urban zoonosis in Brazil. Serological tests and polymerase chain reaction (PCR) on peripheral blood were performed to identify infected dogs in scenarios of higher and lower prevalence of the disease (Teresina and Vitória). One-hundred infected and 57 non-infected animals from Teresina and 100 non-infected animals from Vitória were studied. Animal selection was not dependent on previous serology. The sensitivity (Teresina) and specificity (Teresina and Vitória) were as follows: indirect antibody fluorescence (IFAT) cut-off of 1:40 (IFAT 1:40): 96%, 18%, and 76%; IFAT 1:80: 90%, 33%, and 93%; direct agglutination test (DAT): 96%, 33%, and 98%; fast agglutination screening test (FAST): 93%, 68%, and 100%; immunochromatographic assay with a recombinant rK39 antigen (rK39): 88%, 74%, and 98%; enzyme linked immunosorbent assay (ELISA): 91%, 79%, and 98%; rapid dual-path platform test (TR DPP®): 98%, 60%, and 98%; and blood PCR: 29%, 93%, and 97%, respectively. In the high transmission area, none of the tests adequately discriminated L. infantum-infected from non-infected dogs. However, in the high transmission city, the area under the receiver operating characteristic (ROC) curve of FAST, DAT, ICrK39, ELISA and TR DPP® was high

Ectoparasitismo por Struthiolipeurus rheae (Harrison, 1916) em emas criadas em cativeiro

Os malófagos são piolhos mastigadores, encontrados em aves e mamíferos. Nas emas (Rhea americana) podem causar grandes prejuízos ao comércio, devido à perda da qualidade das plumas, danificação das penas, lesões na pele e debilidade. Sendo assim, objetiva-se com o estudo relatar a infestação por piolhos em emas criadas em cativeiro. Os piolhos foram preservados em álcool 70%, clarificados com lactofenol e montadas as lâminas para observação em microscópio óptico. Nas emas observou-se alterações como desidratação, pele descamada e áspera, penas deformadas, falhadas e opacas e presença de piolhos malófagos da espécie Struthiolipeurus rheae

Histopathological evaluation of the intestine of jabutis (Chelonoidis carbonarius e Chelonoidis denticulatus) reared in captivity and parasitized by helminths (Chapiniella variabilis and Atractis thapari)

El estudio tuvo como objetivo identificar y describir lesiones intestinales ocasionadas por helmintos en jabutis (Chelonoidis carbonarius y Chelonoidis denticulatus) criados en cautiverio en el Parque Zoobotánico de Teresina, estado de Piauí, Brasil. La evaluación parasitológica de 142 de estas tortugas reveló que todas estaban parasitados por helmintos (ascarídeos y estrongilideos), que fueron identificados como Atractis thapari y Chapiniella variabilis por medio de microscopio de luz y microscopio electrónico. Los 12 animales más parasitados (seis de cada especie) fueron eutanasiados y muestras de intestino delgado y grueso fueron evaluadas por histopatología. Macroscópicamente, todos los intestinos, tanto delgado como grueso, presentaban hiperemia. Microscópicamente, en el intestino delgado se observó hiperemia (12/12), hiperplasia difusa de células caliciformes (8/12) y edema de submucosa (1/12). En el intestino grueso se observó hiperemia, variando entre discreta a intensa (12/12) y enteritis transmural granulomatosa focalmente extensa e intensa (1/12).The aim of this study was to identify and describe intestinal lesions caused by helminths in red-footed tortoise (Chelonoidis carbonarius) and yellow-footed tortoise (Chelonoidis denticulatus) reared in captivity in the Zoo and Botanical Park of Teresina, Piauí State, Brazil. The parasitological evaluation of 142 of these tortoises revealed that all were parasitized by helminths (ascarids and strongyles), which were identified as Atractis thapari and Chapiniella variabilis by light and electron microscopy. The 12 most parasitized tortoises (six per species) were euthanized, and samples of small and large intestine were evaluated by histopathology. Macroscopically, all small and large intestines had hyperaemia. Microscopically, hyperaemia (12/12), diffuse goblet cell hyperplasia (8/12) and submucosa oedema (1/12) were observed in the small intestine. Hyperaemia was observed in the large intestine, varying from discrete to intense (12/12) and focally extensive and severe transmural granulomatous enteritis (1/12)

EFEITO DE VERMIFUGAÇÃO ESTRATÉGICA, COM PRINCÍPIO ATIVO À BASE DE IVERMECTINA NA INCIDÊNCIA DE PARASITOS GASTRINTESTINAIS NO REBANHO CAPRINO DA UFPI

Objetivou-se avaliar a eficácia de vermifugação realizada durante um ano no rebanho caprino da raça anglonubiana da Universidade Federal do Piauí, sendo a estratégia adotada caracterizada por vermifugações no período seco e no período chuvoso, com princípio ativo à base de ivermectina em aplicação oral. Avaliou-se a prevalência estacional de nematódeos gastrintestinais em cabritos, machos e fêmeas de seis a dez meses, cabra e reprodutor. Estimou-se o número médio de ovos e larvas de acordo com a época do ano, considerando-se os exames mensais como repetições dentro da época. Os resultados foram interpretados com base em estatísticas descritiva,médias e desvios padrões. Constatou-se baixa prevalência de ovos de nematódeos, oocistos de protozoários e larvas infectantes. Entretanto a variabilidade dentro da estação foi alta e, portanto, não se pode estabelecer com segurança associação entre a freqüência dos parasitas com a categoria animal, nem mesmo com a época do ano, mas há indícios de que a estratégia de vermifugação adotada interferiu no ciclo parasitário, alterando a maior incidência de parasitos gastrintestinais durante o período chuvoso. PALAVRAS-CHAVE: Caprino, helmintos gastrintestinais, protozoários

Evaluation of the serum biochemistry and histopathology of kidney and bladder of dogs with Leishmania sp. in their urine

The visceral establishment of Leishmania infantum in dogs may result in kidney and bladder tissue injury, with L. infantum ending up in urine. This study therefore aimed at investigating the presence of Leishmania sp. in urinary sediments, and correlating the results with those from renal and bladder serum biochemistry and histopathology. Thirty dogs with negative Nested-Polymerase Chain Reaction (PCR) for E. canis were used in the experiment, and were divided into three groups: control group (10 dogs), neither leishmaniasis nor clinical changes; group I (15 dogs), leishmaniasis but no Leishmania sp. in urine; and group II (5 dogs), leishmaniasis, as well as Leishmania sp. in urine. All animals were submitted to clinical, serological, and parasitological diagnosis for leishmaniasis, biochemical exams, and kidney and bladder histopathology. The parasite was also detected in the bladder imprint of one group II dog. Group II dogs presented with very low albumin concentrations, low albumin/globulin ratios, and kidney and bladder lesions. In the kidneys, hydropic degeneration, thickened Bowman's capsule, and thickening of the tubular capsule were detected in all dogs with positive urinary sediment. However, no significant difference in these renal changes was observed between groups. The intensity and distribution of bladder inflammatory infiltrates were significantly (p-value < 0.05, Kruskal-Wallis’ and Dunn’s tests) higher in group II dogs, compared with those of the other groups. The presence of Leishmania sp. in the urine of infected dogs appeared to be related to low serum albumin concentrations and more severe bladder lesions

The performance of serological tests for Leishmania infantum infection screening in dogs depends on the prevalence of the disease

Dogs are considered the main reservoir of Leishmania infantum. This protozoan causes visceral leishmaniasis (VL), an uncontrolled urban zoonosis in Brazil. Serological tests and polymerase chain reaction (PCR) on peripheral blood were performed to identify infected dogs in scenarios of higher and lower prevalence of the disease (Teresina and Vitória). One-hundred infected and 57 non-infected animals from Teresina and 100 non-infected animals from Vitória were studied. Animal selection was not dependent on previous serology. The sensitivity (Teresina) and specificity (Teresina and Vitória) were as follows: indirect antibody fluorescence (IFAT) cut-off of 1:40 (IFAT 1:40): 96%, 18%, and 76%; IFAT 1:80: 90%, 33%, and 93%; direct agglutination test (DAT): 96%, 33%, and 98%; fast agglutination screening test (FAST): 93%, 68%, and 100%; immunochromatographic assay with a recombinant rK39 antigen (rK39): 88%, 74%, and 98%; enzyme linked immunosorbent assay (ELISA): 91%, 79%, and 98%; rapid dual-path platform test (TR DPP®): 98%, 60%, and 98%; and blood PCR: 29%, 93%, and 97%, respectively. In the high transmission area, none of the tests adequately discriminated L. infantum-infected from non-infected dogs. However, in the high transmission city, the area under the receiver operating characteristic (ROC) curve of FAST, DAT, ICrK39, ELISA and TR DPP® was hig