Estudio de infestación de caninos con Echinococcus granulosus en la provincia de La Rioja, Argentina / Study of infestatioon of dogs with Echinococcus granulosus in the province of La Rioja, Argentina

Este trabajo fue realizado en la provincia de La Rioja, ubicada en el noroeste argentino. El objetivo fue estimar el porcentaje de heces de caninos con presencia de antígenos de Echinococcus sp. en las distintas regiones de la provincia. Se tomaron un total de 269 muestras de materia fecal seca de caninos, que fueron analizadas por la técnica de copro-ELISA. La zona más afectada fue la zona IV, que contó con un 30,5% de muestras positivas. La zona I, que corresponde al Departamento Capital, tuvo un 12% de positividad. En el resto de las zonas, los porcentajes variaron entre el 11,4 y el 14,8%. Este es el primer estudio en la provincia sobre la existencia de la enfermedad en caninos. La falta de estrategias para el control de la equinococosis ha permitido la dispersión de la enfermedad

This work was conducted in the province of La Rioja, located in northwestern Argentina. The aim of this study was to estimate the percentage of dog feces showing the presence of antigens of Echinococcus sp. in different regions of the province. A total of 269 samples of dried canine stool were taken, which were analyzed by the copro-ELISA technique. The most affected area was zone IV, which had 30.5% of positive samples. Zone I corresponding to the Capital Department of the province had 12% of positivity. In other areas, the percentages ranged between 11.4% and 14.8%. This is the first study in the province of La Rioja on the existence of this disease in dogs. The lack of control strategies has allowed the spread of echinococcosis

Emprego de estirpes Leptospira spp. isoladas no Brasil na microtécnica de soroaglutinação microscópica aplicada ao diagnóstico da leptospirose em rebanhos bovinos de oito estados brasileiros / Use of Leptospira spp. strains isolated in Brazil in the microscopic agglutination test applied to diagnosis of leptospirosis in cattle herds in eight brazilian states

O objetivo do presente trabalho foi investigar a conveniência do emprego de estirpes de leptospiras autóctones isoladas no Brasil, na coleção de antígenos da microtécnica de soroaglutinação microscópica (SAM) aplicada a leptospirose. Foram amostradas por conveniência 109 propriedades e 9820 bovinos, fêmeas em idade reprodutiva, distribuídos em 85 municípios, dos Estados de Goiás, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Paraná, Rio Grande do Sul, Santa Catarina e São Paulo. Dos 9820 animais examinados, 5806 (59,12%) foram reagentes na SAM para pelo menos um sorovar com a coleção de 23 sorovares de referência. Com a coleção de antígenos de referência e dez estirpes autóctones houve 6400 (65,17%) reagentes, com diferença significativa entre as proporções (p=0,001). Os sorovares mais prováveis identificados com a coleção de antígenos de referência foram Hardjo (43,03%), Shermani (20 %), Wolffi (9,96%), Grippothyphosa (5,42%) e Pomona (4,28%). Com a coleção ampliada por dez estirpes isoladas no Brasil, os sorovares mais prováveis foram Hardjo (31,00%), Guaricura-M4/84 (22,50%), Shermani (15,43%), Wolffi (4,76%), Grippothyphosa (3,71%) e Autumnalis (3,24%). O sorovar Guaricura, estirpe M4/84, isolada de bovinos e búfalos no Estado de São Paulo, despontou como um dos três sorovares mais freqüentes nos Estados de Goiás, Mato Grosso, Mato Grosso do Sul, Minas Gerais e São Paulo. A introdução de estirpes autóctones na coleção de antígenos da SAM propiciou a confirmação do diagnóstico de leptospirose em 594 animais (6,00%) classificados como não reagentes pela coleção de referência (p=0,001).

The aim of this study was to investigate the adequacy of the use of autochthonous strains of leptospires isolated in Brazil, added to antigen collection of the microscopic agglutination test (MAT) applied to the diagnosis of bovine leptospirosis. By means of non-probability sampling, 109 farms and 9,820 cattle, females at reproductive age were chosen from 85 municipalities in the states of Goiás, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Paraná, Rio Grande do Sul, Santa Catarina and São Paulo. Among the 9,820 examined animals, 5,806 (59.12%) were reactants at MAT for at least one serovar using the 23 reference serovars. Employing the collection of reference serovars and the ten autochthonous strains, 6,400 (65.24%) reactants and significant difference (p=0.001) was found. The most probable serovars identified by the collection of reference antigens were Hardjo (43.03%), Shermani (20%), Wolfi (9.96%), Grippothyphosa (5.42%) and Pomona (4.28%). With the collection amplified with the ten strains isolated in Brazil, the most probable serovars were Hardjo (31%), Guaricura-M4/84 (22.50%), Shermani (15.43%), Wolffi (4.76%), Grippothyphosa (3.71%) and Autumnalis (3.24%). The serovar Guaricura, strain M4/84, isolated from bovines and buffaloes in the State of São Paulo, was ranked as one of the three most probable serovars in the states of Goiás, Mato Grosso, Mato Grosso do Sul, Minas Gerais and São Paulo. The addition of autochthonous strains to the MAT antigen collection provided the confirmation of the diagnosis of leptospirosis in 594 cattle (6%) which have been classified as non-reactants by the reference collection (p=0.001).

Value of purified schistosoma snails antigens in diagnosis of schistosomiasis

This study was done to assess the value of purified Schistosoma snails antigens in diagnosis of schistosomiasis. Five antigens were used, S.mansoni adult worm crude antigen, snails antigens [foot and visceral hump of B.alexandrina and B.truncatus]. Specific hyperimmune mice sera versus each antigen were prepared. Known positive and negative human sera and uninfected mice sera were used as control. Two ELISA techniques [conventional and sandwich] were performed. There was high similarity between S.mansoni crude antigen and B.alexandrina foot antigen in detecting S.mansoni antibodies [100% and 80% respectively] at serum dilution 1:50. B.alexandrina visceral hump antigen detected only 33.3%. Both B.truncatus antigens gave negative results. Sandwich ELISA technique proved to be more species specific than conventional ELISA. B.alexandrina foot antigen was found to be the best antigen among the tested antigens that can replace S.mansoni adult worm crude antigen in diagnosis of schistosomiasis

Production of Trichophyton mentagrophytes antigens and their characterization in mice

The participation of dermatophytic antigens in the host-parasite balance is still poorly understood. One of the difficulties encountered by researchers is the lack of dominant and specific antigens that can be used in such studies. In order to contribute to a better understanding of this aspect of infection, the present study identifies antigen fractions obtained from exoantigen and cytoplasmic extracts of Trichophyton mentagrophytes. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) revealed the presence of 13 proteins in the exoantigen extract, whose molecular weight ranged from 12.5 to 90 kDa. The cytoplasmic extract contained 18 protein fractions ranging from 11 to 110 kDa. Immunoblotting showed the presence of immunodominant antigens against IgG, IgM and IgA antibodies. This affinity was observed in three proteins of the exoantigen extract and in three proteins of the cytoplasmic extract, with respective molecular weights of 33, 39 and 59, and 40, 55 and 82 kDa. These results are promising, especially when considering that these extracts contain antigenically distinct protein fractions which, once determined, may contribute to a better understanding of dermatophytoses, and may thus help in the development of alternative strategies for the diagnosis and treatment of this condition.

Fasciola hepatica: identificação in situ de antígenos / In situ identification of Fasciola hepatica antigens

O presente estudo objetivou avaliar antígenos excretórios/ secretórios (Ag E/S) e somáticos (Ag S) de Fasciola hepatica, anticorpos específicos e demonstrar a presença de sítios reativos em corte histológico do parasito adulto pela técnica de imunoistoquímica. A resposta imune foi observada pela reação intensa nas células que circundam a ventosa ventral do parasito. A técnica de imunoistoquímica é sensível e de fácil execução na detecção de sítios antigênicos em cortes histológicos de Fasciola hepatica.

The aim of the present study was to assess excretory-secretory antigens and somatic antigens of Fasciola hepatica, specific antibodies, and to identify reactive sites in histological sections of adult parasites by means of immunohistochemistry. The immune response was observed through the intense reaction of cells that surround the ventral sucker of Fasciola hepatica. lmmunohistochemistry is a sensitive and easy-to-use method for detecting antigenic sites in histological sections of this parasite.

Immunization of rabbits against Hyalomma anatolicum anatolicum tick using antigens derived from whole tick and gut extract

This study was conducted in three phases for identification of protective antigens in Hyalomma anatolicum anatolicum that can induce the best protection in the sheep and cattle. In the first phase of study, H. anatolicum anatolicum was cultured for preparing enough antigens. Then, four antigenic preparation, viz, whole tick supernatant antigen [WTSA], whole tick pellet antigen [WTPA], gut supernatant antigen [GSA] and gut pellet antigen [GPA] were made partially fed adult female H. anatolicum anatolicum. Four groups of five rabbits were immunized with the antigens in Freund's adjuvant emulsion and a fifth group was kept as control. The rabbits were challenged with ten pairs of homologus ticks and characteristic representing tick feeding and fertility were recorded and compared between groups. A significant decrease in percent of engorgement, index feeding, percent of oviposited, weight of egg and index fertility were observed in GSA immunized rabbits

Studies on concomitant antigens of Bithynia funiculata for detection of antibody to Opisthorchis viverrini: effect of different centrifugal speeds on antigen preparation.

Antigens derived from somatic extracts of Bithynia funiculata, an intermediate snail host of O. viverrini, have been demonstrated to be highly heterogeneous in molecular weight (MW). These antigens have been suggested to be of potential use for serodiagnosis. In this study, B. funiculata somatic antigens were extracted using five different centrifugal speeds, namely 10,000 (C1); 20,000 (C2); 30,000 (C3); 40,000 (C4) and 50,000 (C5) rpm, with the aim of removing some non-specific antigens and determining the optimal centrifugal speed to obtain the highest efficiency of the test for which they will be used. The enzyme-linked immunosorbent assay technique was used to compare the reactivity of the five different centrifugal speed-prepared antigens. The sensitivity and specificity of all five antigens were compared by testing against sera from 81 opisthorchiasis patients, 30 parasite-free healthy individuals and 50 individuals infected with other helminthic infections, using mean + 4SD of all healthy individuals as the cut-off value. The sensitivity of these antigens was 69.1, 84.0, 80.2, 84.0 and 70.4, respectively; while the specificity was 66.2, 76.2, 82.5, 86.2 and 71.2, respectively. Immunoreactive components of each antigen were analyzed by SDS-PAGE and Western blot technique. The assay showed that three pairs of antigens with MW of 29 and 30, 47 and 50, and 86 and 90 kDa of all five antigens, which have previously been shown to be highly immunogenic, still reacted with a pooled serum from patients with opisthorchiasis. However, the C4 antigens gave more distinct components. Our results showed that 40,000 rpm is the optimal speed for antigen preparation for use in the serological diagnosis of opisthorchiasis, as demonstrated by the most satisfactory results of both sensitivity and specificity in the indirect ELISA and Western blot technique.

Modelo biológico para la detección de antígenos alimentarios / Biological model for detection of food antigens

Antigenic macromolecules present in food can induce inflammatory allergic reaction in sensitized persons. The aim of the present work is the development of an animal model to detect food antigens based on hypersensitivity reaction after food ingestion. New Zealand rabbits were divided in 5 groups. Group 1 (GI): control. G2: Ovalbumin (OVA) sensitized. G3: sensitized and orally challenged with OVA. G4: OVA sensitized and phosphate buffer solution challenged (PBS). G5: sensitized and challenged with OVA. Samples from cecum were stained with Alcian Blue pH < 1 for mast cells and with silver method for enteroendocrine cells (EEC). Other samples were immunostained with anti CD5 and CD25 monoclonal antibodies. Specific IgE levels were detected by PCA. Histopathology of G5 showed patchy edema, lymphangiectasia and eosinophilic infiltration. Results were expressed as cells per HPF (high power field); Mast cells in G1: 1.33; G2: 12.80 and G5: 10.20. Enteroendocrine cells in surface epithelium: G1: 1.6; G2: 6.0; G5: 4.2 and in deep epithelium: G1: 3.0; G2: 12.0 and G5: 7.3. Lymphocytes CD5+ in G1: 24.21: G2: 22.12 and G5: 23.97 and CD25+ in G1: 12.10: G2: 14.30 and G5: 21.68. Group 3 were similar to G1 and G4 to G2. We observed: mast cells increased in number probably due to OVA induced response. EEC showed an increase in sensitized animals because of higher expression of cytoplasmatic granules or differentiation from stem cells. Decrease in EEC number in challenged groups was likely to be based on vesicles release. Total T cells showed no significant differences among groups. CD 25+ cells were higher in sensitized and challenged animals. We concluded that rabbit model of sensitization and oral challenge is valid to study ingested food antigens and potential digestive pathologic reactions.

Trichomonas tenax: protozoario flagelado de la cavidad bucal. Consideracione generales / Trichomonas tenax: flagellate protozoan of the oral cavity. General considerations

En el presente artículo se describen los principales aspectos relacionado con Trichomonas tenax, protozoario que se encuentra en la cavidad bucal humana de algunos individuos, en donde se destacan: historia, taxonomía, características morfológicas, fisiológicas y de cultivo, estructura antigénica, biología molecular, así como algunas consideraciones en referencia a la ecología y a la patogenicidad por parte de este microorganismo, tanto dentro como fuera de los límites de la cavidad bucal

Diversidade antígena entre amostras de Arcobacter spp isoladas de suínos no Rio Grande do Sul e presença de anticorpos aglutinanates em amostras de soro de porcas com problemas reprodutivos / Antigenic diversity among strains of Arcobacter spp isolated from pigs in Rio Grande do Sul, Brazil and presence of agglutinin titers in serum samples of sows with reproductive problems

O teste de aglutinaçäo microscópica, usando a técnica descrita para o diagnóstico de leptospirose, foi utilizado para verificar a antigenicidade de 47 amostras de Arcobacter cryaerophilus e duas amostras de Arcobacter butzleri isoladas de suínos no Rio Grande do Sul, Brasil, em frente a soros hiperimunes produzidos em coelhos a partir de amostras padröes das bactérias. Verificou-se grande heterogeneidade antigênica e apenas quatro amostras provocaram títulos acima de 1.600 com os anti-soros padröes. A classificaçäo genética dos microorganismos foi confirmada no teste em 48,97 por cento dos antígenos. Igualmente, utilizando a técnica de aglutinaçäo microscópica, foram testadas amostras de soro de porcas que apresentaram problemas reprodutivos, procedentes de granjas de onde foram isoladas amostras de Arcobacter spp. Näo existe registro anterior na literatura sobre o uso do referido teste em infecçöes por Arcobacter spp. Os exames sorológicos em fêmeas suínas reprodutoras revelaram títulos de até 1.600, possibilitando indicar que houve a presença de aglutininas para Arcobacter spp.

Diagnostic efficiency of Brucella soluble antigens in immunodiffusion tests and ability to differentiate Brucella abortus strain 19 vaccinated cattle

Foram comparados três antígenos solúveis: um hapteno nativo (NH) de B. melitensis 16M, um polissacarídeo (PS) obtido de B. abortus 1119-3 e outro polissacarídeo de cadeia O (O-Chain) originado também da última Brucella. Os testes de imunodifusão radial (RID) e imunodifusão em gel de ágar (AGID) foram confrontados com as três classes de soros bovinos: a) infectados naturalmente (n = 76), b) não infectados (n = 130) e c) vacinados com B19 (n = 61) reagindo a testes sorológicos clássicos. Foram determinadas a sensibilidade (Se), a especificidade (Sp) e a capacidade para discriminar vacinados (ADV). A Se mais alta (84,3%) no teste RID foi demonstrada pelo antígeno NH, enquanto os três antígenos tiveram 100% de Sp. O antígeno O-Chain teve 100% de ADV nesse teste. O teste AGID com estes antígenos demonstrou 100% Sp e ADV, enquanto o antígeno PS mostrou uma melhor Se (86,6%). Finalmente, por sua qualidade de produção e eficiência, os antígenos PS e NH representam uma alternativa segura e econômica para o diagnóstico suplementar da brucelose.

Purificacion de antigeno de Candida Albicans para pruebas cutaneas: Estudio Preliminar / Candida Albicans antigen purification for skin test: preliminary study

La evaluacion de la inmunidad celular mediante la respuesta producida por los linfocitos T, que son estimulados por la presencia de un antigeno determinado, es de sumo interes para el tratamiento de diversas enfermedades infecciosas que se producen durante el transcurso de quemaduras, lesiones, traumatismos, etcetera, por lo que la obtencion de antigenos purificados para su uso en pruebas cutaneas que se emplean para dicha evaluacion es de gran importancia. En nuestro trabajo nos dimos a la tarea de desarrollar un metodo de purificacion para la obtencion de uno de estos antigenos, a partir de la Candida albicans. El metodo utilizado fue el descrito por Buckley et al., al cual se le realizaron modificaciones. Se encontro que la metodologia era adecuada y reproducible, pues el antigeno obtenido tenia caracteristicas similares al antigeno de referencia

Leishmania brasiliensis: isolation of carbohydrate-containing antigen and possibility of its use in the immunodiagnosis of american cutaneous leishmaniasis

A Leishmania brasiliensis e um dos agentes causadores da Leishmaniose Tegumentar Americana (LTA). A cepa 034-jcg, isolada de paciente da regiao norte do estado do Parana, Brasil, foi cultivada em meio Blood Agar Base, liofilizada e submetida a extracao com fenol-agua e o extrato obtido foi tratado com RNase I. O antigeno contendo carboidrato (AgCHO) mostrou-se imunogenico para coelhos e apresentou pelo menos uma fracao com poucas cargas negativas em pH 8,2. Este antigeno apresenta reacao cruzada com extrato fenolico do meio de cultura usado para o cultivo de promastigotas...

Detección de antígenos fecales de cryptosporidium parvum mediante técnica de ELISA / Detection of cryptosporidium parvum fecal antigens by ELISA technic (AU)

ELISA techniques using monoclonal antibodies have been recently developed for the detection of cryptosporidium parvum fecal antigens. The aim of this work was compare the yield of these ELISA techniques with Ziehl-Nielsen and Safranin stains in formaldehyde-salt fixed samples. One hundred five fecal samples of patients with acute diarrhea were studied. Forty seven samples did not contain cryptosporidium and ELISA was negative. Also, ELISA was positive in 52 of 58 that contained Cryptosporidium (89.6 percent), the samples with false negative results containing scanty oocysts. Seven intensily positive Paf-fixed stool samples from AIDS patients with chronic diarrhea, were not reactive to ELISA. There was a good correlation between visually and mechanically read samples and there were no false positive. It is concluded that ELISA cannot be used in Paf-fixed samples and has a lower sensitivity that the stained commonly used for the diagnosis of cryptosporidiosis

Antígeno nuclear de proliferación celular (PC10) en pacientes con síndrome de malabsorción: estudio comparativo con parámetros morfométricos / Proliferating cell nuclear antigen (PCNA) in patients with malabsorption syndrome: comparative study with morphometric parameters

The study of small bowel mucosa is routine in the study of patients with malabsorption. We report 16 children aged from 8 months to 6 years old (2 with giardiasis, 8 with primary malnutrition and 5 with celiac diasease) in whom a morphometric and PCNA immunostaining was performed in the small intestinal biopsy. Positively for PCNA was found in the lower portion of the crypts reaching 156 µm of heigh in patients with giardiasis, 103 µm in primary malnutrition and 182 µm in celiac dosease (p<0.01 compared to primary malnutrition). A negative and significant correlation was found between the degree of architectural disorder (expressed the mucosal index) and the proliferative portion of the crypts (expressed as the percentage of PCNA(+) crypts. We propose these methods as complements to the small bowel mucosa histopathological study in the diagnosis of celiac disease, to assess the degree of architectural disorder and the proliferative activity

Evaluación inmunorradiométrica de orina humana y murina como especímenes para la detección de antígenos de trypanosoma cruzi / Immunoradiometric evaluation of human and murine urine as specimens for the detection of trypanosoma cruzi antigens

En orina de ratones, infectados en forma aguda experimental con la cepa Tulahuén de T cruzi, se detectó señales radioautográficas en inmunodot, desarrollado con suero humano chagásico. En inmunoelectrotransferencia (IET) de orina murina concentrada, desarrollada con suero de humanos seropositivos, se detectó bandas de pesos moleculares 66, 56 (también presentes en orinas normales), 19, 12, 10 y 8 kDa. En orina de humanos seropositivos, sometida a IET contra una dilusión adecuada de sueros de estos mismos individuos se detectó bandas de 66, 56 (también presentes en orinas normales), 87, 46, 36 y 26 kDa. Hubo diferencias importantes en relación al número de éstos polipéptidos presentes en cada muestra. Curiosamente, si todos estos polipéptidos urinarios se enfrentan en IET a sueros humanos normales (seronegativos para T cruzi), son detectados en grado variable. este problema, a pesar de la sensibilidad de los ensayos usados y de la extensiva concentración a que se sometió los especímenes, cuestiona seriamente la especificidad del método, por lo cual el uso de orina como especímen para el diagnóstico expedito de Chagas, experimental y humano, no parece ser muy promisorio

Evaluation of specific fasciola gigantica antigens for the diagnosis of fascioliasis in experimentally and naturally infected sheep by ELISA

The value of peak II and E/S Fasciola antigens for diagnosis of experimental and natural sheep fascioliasis were studied by ELISA. The antibody levels of experimentally infected sheep with F. gigantica which appeared at 2 weeks post-infection, gradually increased and the highest concentration of antibodies was found 9 - 13 weeks post- infection with both antigens. Also, both antigens gave 100% sensitivity for diagnosis of naturally infected sheep with fascioliasis. On the other hand, peak II antigen gave 100% specificity, while E/S antigen gave 94.29% specificity