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Sample records for serologicos por elisa

  1. Utilidad de sangre almacenada en papel de filtro para estudios serologicos por ELISA de inhibicion Use of filter paper strips on an ELISA inhibition test for serologic studies on dengue

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    S. Vázquez

    1991-08-01

    Full Text Available Para evaluar la utilidad del método de recolección de muestras de sangre en papel de filtro para la detección de anticuerpos anti-dengue mediante un ELISA de Inhibición recientemente desarrollado en nuestro laboratorio, se realizó una toma simultánea de muestras de sangre en papel de filtro y de suero, de donantes de Banco de Sangre. Ambas muestras fueron conservadas a -20ºC y probadas a los 15 dias, 3 y 6 meses respectivamente. A las muestras que resultaron positivos se les amplió el rango de dilución para determinar título. Al realizar la comparación entre ambas muestras, sangre en papel de filtro y suero, encontramos que no existían diferencias de detección significativas, tanto para los casos positivos como los negativos. No obstante se observó en ambas muestras y de forma general una disminución del titulo de anticuerpos (una dilución al transcurrir el tiempo máximo establecido en nuestro estudio (6 meses.To evaluate the usefullness of the collecting method of blood samples in filter paper strips for anti-dengue antibody detection using an ELISA Inhibition test which has been recently developed in our laboratory, blood samples collected on filter paper strips and serum samples were obtained from the same blood donors. Both samples were kept at -20ºC and tested at 15 days, 3 and 6 months. Titers were determined in positive samples. Comparing the results, no significant differences were found between serum samples and blood samples collected in filter paper strips in relation to the number of negative and positive cases. Nevertheless, it was observed in both types of samples a decrease of the antibody titers (one dilution in the longest period of our study (6 months.

  2. Elisa Mújica: verdadera vocación por la escritura

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    Nelly Rocío Amaya Méndez

    2001-01-01

    Full Text Available Son excepcionales las escritoras colombianas de las que puede decirse que con su obra han conquistado las más altas cimas del valor literario en géneros como la novela, el cuento y el ensayo, y obtenido al mismo tiempo su consagración dentro del ámbito de las letras hispanoamericanas. Es el caso de doña Elisa Mújica, considerada modelo en el arte de escribir en Colombia gracias a su dedicación y disciplina durante decenios de continuo quehacer literario, siendo la primera mujer en ser admitida en la Academia Colombiana de la Lengua y como miembro correspondiente de la Real Academia Española

  3. Detección de anticuerpos antiplasmodium por ELISA en donantes de sangre

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    Patricia Olaya de Morales

    1982-06-01

    Full Text Available La malaria, una enfermedad transmitida por mosquitos del genero anopheles, puede ser inducida a través de transfusiones de sangre infectada con alguna de las especies de Plasmodium que afectan al hombre. Con el objeto de determinar el riesgo potencial de infección inducida por transfusiones, se analizaron durante 9 meses y mediante la técnica de E.L.I.S.A., las muestras de suero tomadas a los donantes de sangre del Hospital Militar Central de Bogotá. El 8.6 por mil de las 3114 muestras analizadas, resultaron positivas para anticuerpos antimaláricos y durante el tiempo del estudio fueron detectados 3 casos de malaria inducida por transfusiones.

  4. Fiebre Tifoidea Diagnóstico por pruebas inmunoenzimáticas: Elisa

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    Miguel Guzmán

    1981-06-01

    Full Text Available Este trabajo describe el desarrollo y normalización de una técnica inmunoenzimática para el diagnóstico indirecto de la Fiebre Tifoidea. El método permite un análisis simple y objetivo de los resultados. La reacción enzimática es proporcional a la concentración de anticuerpos en el suero contra el antígeno somático-0, por tanto, el método es cuantitativo. Por lo demás, la técnica tiene un alto grado de especificidad para Salmonella typhi, ya que los sueros de pacientes con Salmonelosis causada por Salmonella enteritidis serotipos paratyphi A, B y typhimurium dieron resultados negativos, en forma similar a los presentados por el grupo control antes de la vacunación específica. Los resultados obtenidos con esta técnica permitieron definir el nivel de anticuerpos que puede presentar una población control supuestamente sana frente a los niveles inducidos por la enfermedad. Los resultados postvacunales en el grupo control mostraron títulos sorprendentemente bajos; un análisis de este fenómeno se presentó en forma amplia. Igualmente se proponen futuras investigaciones sobre este campo.

  5. Comparação entre diversos antígenos para o diagnóstico de Anaplasma marginale por ELISA Comparison between several antigens for diagnosis of Anaplasma marginale by ELISA

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    Carlos A.N. Ramos

    2010-01-01

    Full Text Available Anaplasmose bovina é uma doença com grande importância nas regiões tropicais e subtropicais do mundo por determinar perdas econômicas devido à mortalidade e redução da produtividade. É causada por Anaplasma marginale, uma riquétsia intraeritrocítica obrigatória cujo controle requer, além de uma vacina eficiente, uma acurada identificação de bovinos cronicamente infectados. Apesar de existirem atualmente diversos métodos de diagnóstico dessa riquétsia, os métodos sorológicos, em particular o ensaio de imunoadsorção enzimática-ELISAs, são os mais utilizados devido à sua versatilidade e praticidade. No entanto, devido ao grande número de antígenos disponíveis, atualmente torna-se necessária uma avaliação para definir quais antígenos apresentam um melhor desempenho no diagnóstico da anaplasmose. Soros de bovinos positivos e negativos para A. marginale por PCR, e soros de animais provenientes do Brasil e Costa Rica, foram testados em ELISAs baseados em MSP1a, MSP2 e MSP5 recombinantes, um pool das três proteínas recombinantes, e antígeno de lisado de corpúsculos iniciais da riquétsia (CI. Utilizando soro de bovinos positivos para A. marginale por PCR, uma maior sensibilidade foi observada no ELISA CI. No entanto, uma maior especificidade, com soro de bovinos negativos a PCR, foi observada com os ELISAs recombinantes. O porcentual de bovinos positivos do Brasil e Costa Rica foi maior com ELISA CI. Razões para essas diferenças são discutidas.Bovine anaplasmosis is a major disease in tropical and subtropical regions of the world by determine economical loss due mortality and productive reduction. The disease is caused by Anaplasma marginale, an intraerythrocytic rickettsia whose control requires, besides an efficient vaccine, the accurate identification of chronically infected cattle. Although the existence of diverse methods of diagnosis of this rickettsia, the serological methods, in particular the enzyme

  6. Nivel de corte de los ELISAs para cuantificación de anticuerpos inducidos por la vacuna antimeningocócica VA-MENGOC-BC

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    Rolando Ochoa

    2001-06-01

    Full Text Available Para medir el grado de protección inducido por vacunas antimeningocócicas se ha establecido el Ensayo Bactericida en Suero (EBS y se perfeccionan otros ensayos inmunobiológicos, sin embargo, es necesario contar con pruebas sencillas como el ELISA, capaz de evaluar un gran número de muestras. Se estimó el nivel de corte de los ELISAs para la cuantificación de IgG humana contra los antígenos de VA-MENGOC-BC, vacuna antimeningocócica compuesta por vesículas proteicas de membrana externa de meningococo B y polisacárido capsular de meningococo C, con respecto a un panel de muestras de suero de lactantes, caracterizado por Ensayo Bactericida en Sangre Total (EBST. Los valores correspondientes a la máxima sensibilidad y especificidad fueron respectivamente; 2 μg/mL y 12 μg/mL para antipolisacárido C, y 1000 U/mL y 7000 U/mL para antiproteínas de membrana externa. La mayor coincidencia se obtuvo con 6 μg/mL y 2500 U/mL. Se evaluó otro panel de muestras de suero de adolescentes entre 14 y 18 años, por ELISA y EBS para Neisseria meningitidis serogrupos B y C, alcanzándose una buena concordancia. Doce años después de la inmunización con VA-MENGOC-BC persiste una importante concentración de anticuerpos contra los antígenos vacunales en los sueros estudiados.

  7. Inmunodiagnóstico de la infección en humanos por Trypanosoma cruzi mediante ELISA utilizando sangre recolectada en papel de filtro

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    Luis C. Orozco

    1999-06-01

    Full Text Available Los estudios seroepidemiológicos para la detección de anticuerpos contra Trypanosoma cruzi requieren de un gran número de muestras y la obtención de sangre por punción venosa y su transporte se hacen difíciles y costosos. La recolección de sangre en papel de filtro minimiza éstas dificultades y el estudio valoró tanto éste sistema como la validez y reproducibilidad del inmunoensayo ELlSA para el inmunodiagnóstico de la infección en humanos por T cruzi Se utilizó suero y eluídos de sangre recolectada en papel de filtro de personas de zona endémica de enfermedad de Chagas para la detección de anticuerpos contra T cruzi mediante las pruebas de inmunofluorescencia indirecta (IFI y ELISA. Lavalidez del ELlSA utilizando eluídos de sangre en papel de filtro presentó un área bajo la curva de receptor operador (ROC de 0.9944. El acuerdo del ELlSA entre los dos tipos de muestra presentó una distribución cercana a la normal con un promedio de -0.01 y una desviación estándar de 0.23. Se evidenció que la reproducibilidad del IFI es inferior a la del ELISA. Esta mayor concordancia y la mayor sensibilidad y especificidad encontrada previamente para el ELISA hacen pensar en la posibilidad de presentarla como alternativa de prueba de referencia para la detección de anticuerpos contra 7: cruziy su utilización en estudios epidemiológicos.

  8. Usefulness of serological ELISA assay for Taenia saginata to detect naturally infected bovines Utilização de teste sorológico ELISA para a detecção de bovinos naturalmente infectados por Taenia saginata

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    Silvana de Cássia Paulan

    Full Text Available Bovine cysticercosis, a cosmopolitan disease caused by Taenia saginata, leads to economic losses due to carcass devaluation at slaughter. Sanitary inspection at slaughterhouses, the routine diagnostic method in Brazil, lacks the necessary sensitivity to detect the mildly infected cattle that are typically encoutered in Brazil. In this study we have tested cattle sera from animals diagnosed as positive and negative by veterianry inspection for (1 anti-parasite antibodies using metacestodes antigens (T. solium vesicular fluid and T. saginata secretions and (2 the HP10 secreted antigen of viable metacestodes. The cut-off values were calculated by ROC curve for intense and mild infections conditions, and by the classical method ( for negative samples. The sensitivity and specificity of these diagnostic tests were different depending on the assumed cut-off value and, importantly, whether the infection was mild or intense. In spite of these observations, however, such ELISA assays for serum antibodies and parasite antigens constitute an important tool for epidemiological porposes, and in establishing priorities for the control of bovine cysticercosis.A cisticercose bovina, uma doença cosmopolita causada pela Taenia saginata, resulta em perdas econômias devido à desvalorização de carcaças durante o abate. A inspeção sanitária nos frigoríficos, método de diagnóstico de rotina no Brasil, não possui sensibilidade necessária para detectar animais levemente infectados, os quais são tipicamente encontrados no Brasil. Neste estudo testou-se soro de animais diagnosticados positivos e negativos pela inspeção veterinária por (1 anticorpos anti-parasita usando antígenos de metacestóides (fluido vesicular de T. solium e secreções de T. saginata e (2 antígeno secretado de metacestóides viáveis. Os pontos de corte foram calculados pela curva ROC, considerando condições de intensa e leve infeção, e pelo método clássico ( das amostras

  9. Fas2-ELISA y la técnica de sedimentación rápida modificada por lumbreras en el diagnóstico de la infección por Fasciola hepática

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    Vicente Maco Flores

    2002-04-01

    Full Text Available La fasciolosis humana es un problema de salud pública debido a la mayor incidencia de casos reportados en los últimos años alrededor del mundo. La necesidad de contar con técnicas o métodos de diagnóstico para Fasciola hepatica de mayor sensibilidad y especificidad es importante tanto para la práctica clínica como para determinar zonas endémicas. Objetivo: Evaluar las técnicas coprológicas y serológicas para el diagnóstico de la infección por Fasciola hepatica en humanos. Material y métodos: La población de estudio comprendió a niños en edad escolar entre 1-16 años de edad, pertenecientes a una zona de alta endemicidad (Junin, Perú. Se obtuvieron un total de 194 muestras de heces y 158 muestras de suero. Se evaluaron tres métodos coproparasitológicos: Método de Concentración éter-formol (MCEF, Técnica de Sedimentación Espontánea (TSE y la Técnica de Sedimentación Rápida (TSR modificada por Lumbreras, y tres métodos serológicos: Arco 2, Western blot para F. hepatica y Fas2-ELISA. Resultados: La TSR modificada por Lumbreras fue la de mayor rendimiento (20.61% en comparación con la TSE (13.40% y MCEF (7.72%. La sensibilidad de Fas2-ELISA fue de 96.77% superior a la del Western blot y Arco 2, con sensibilidades de 71.87% y 35.48%, respectivamente. Conclusiones: La TSR es superior a TSE y MCEF para el diagnóstico de la fasciolosis humana en la fase crónica. Fas2-ELISA, es una prueba de inmunodiagnóstico altamente sensible y que se propone debe ser usada como la prueba de diagnóstico de fasciolosis humana y de tamizaje de la infección en poblaciones humanas que habitan en regiones de alta endemicidad para esta parasitosis.

  10. Comportamento do método quimioluminescente-ELISA em relação a resultados considerados discordantes por meio de três técnicas convencionais para diagnóstico da doença de Chagas Behavior of the chemiluminescent ELISA method in relation to results considered discordant via three conventional techniques for diagnosing Chagas disease

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    Cláudia Regina De Marchi

    2007-02-01

    Full Text Available Quando utilizadas, em conjunto, a hemaglutinação indireta, a imunofluorescência indireta e ELISA para diagnóstico sorológico da doença de Chagas por vezes ocorrem resultados considerados discordantes, por não haver concordância entre o que indicam essas técnicas. A disponibilidade do método quimioluminescente-ELISA permitiu executá-lo com 200 soros que examinados pelos três testes citados que motivaram a obtenção de resultados discordantes. Com o método quimioluminescente-ELISA sucederam 193 negativos e sete positivos. O emprego desse novo procedimento trouxe mais um subsídio para compreensão do assunto, mas avanço mais concreto dependerá de documentação com soros de pessoas infectadas ou não pelo Trypanosoma cruzi conforme comprovação parasitológica.When indirect hemagglutination, indirect immunofluorescence and enzyme-linked immunosorbent assay are used together for serologically diagnosing Chagas disease, results that are considered discordant sometimes occur because there is disagreement between what these tests indicate. The availability of the chemiluminescent ELISA method enabled tests on 200 serum samples that had previously produced discordant results from the three abovementioned methods. CL-ELISA revealed that 193 of these samples were negative and seven were positive. The use of this new procedure provides further support for understanding this subject, but more concrete advances will depend on documentation with blood analyses from people previously demonstrated to be unquestionably infected or uninfected with Trypanosoma cruzi.

  11. Elisa Miller | NREL

    Science.gov (United States)

    Elisa Miller Photo of Elisa Miller Elisa Link-Miller Researcher III-Chemistry Elisa.Miller@nrel.gov | 303-384-6777 Dr. Elisa Miller-Link studies the surface of semiconductors that are applicable for , and other nanocrystalline films. Elisa came to NREL in 2013 as an NREL Director's Fellowship recipient

  12. Characterization and optimization of bovine Echinococcus granulosus cyst fluid to be used in immunodiagnosis of hydatid disease by ELISA Caracterização e otimização do líquido vesicular de Echinococcus granulosus bovino para utilização no imunodiagnóstico da hidatidose por ELISA

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    Oscar IRABUENA

    2000-10-01

    Full Text Available The aim of this work was to assess the influence in the diagnostic value for human hydatid disease of the composition of bovine hydatid cyst fluid (BHCF obtained from fertile (FC and non-fertile cysts (NFC. Eight batches from FC and 5 from NFC were prepared and analysed with respect to chemical composition: total protein, host-derived protein, carbohydrate and lipid contents. No differences were observed in the first two parameters but carbohydrate and lipid contents were shown to be higher in batches from FC than in those from NFC. Bands of 38 and 116 kD in SDS-PAGE profiles were observed to be present in BHCF from FC only. Two pools were prepared from BHCF batches obtained from FC (PFC and NFC (PNFC, respectively. Antigen recognition patterns were analysed by immunoblot. Physicochemical conditions for adsorption of antigens to the polystyrene surface (ELISA plates were optimized. The diagnostic value of both types of BHCF as well as the diagnostic relevance of oxidation of their carbohydrate moieties with periodate were assessed by ELISA using 42 serum samples from hydatid patients, 41 from patients with other disorders, and 15 from healthy donors. Reactivity of all sera against native antigen were tested with and without free phosphorylcholine. The best diagnostic efficiency was observed using BHCF from periodate-treated PFC using glycine buffer with strong ionic strength to coat ELISA plates.O objetivo do presente trabalho foi testar a composição química do líquido hidático bovino (BHCF obtido de cistos hidáticos férteis (FC e não férteis (NFC. Oito lotes de FC e 5 de NFC foram preparados e testados quanto à composição química, proteínas totais, proteínas derivadas do hospedeiro, conteúdo de carbohidratos e lipídeos. Não foram observadas diferenças entre os dois primeiros parâmetros sendo que o conteúdo de carbohidratos e lipídeos foi maior nos lotes FC do que nos NFC. Por SDS-PAGE foram observadas bandas de 38 e 116 k

  13. Detection of anti-Toxoplasma gondii antibodies in experimentally and naturally infected non-human primates by Indirect Fluorescence Assay (IFA and indirect ELISA Detecção de anticorpos anti-Toxoplasma gondii por meio das técnicas de Imunofluorescência Indireta e ELISA Indireto em primatas experimentalmente e naturalmente infectados

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    Andréa Bouer

    2010-03-01

    Full Text Available The Indirect Fluorescence Assay (IFA and the indirect ELISA were comparatively used to detect IgG and IgM antibodies for Toxoplasma gondii in experimentally and naturally infected primates. In the experimentally infected group, antibodies of diagnostic value were detected at day 9 post-infection (PI with the IFA (IgG and IgM and with IgG-ELISA. IgM-ELISA detected antibodies for T. gondii starting at day 3 PI until the end of the experiment (102 days PI. Of the 209 naturally infected sera tested, from many zoos of State of Sao Paulo, 64.59 and 67.94% were positive in the IgG-IFA test and IgG-ELISA respectively. IgM-ELISA test detected seropositivity in 52.63% of the sera although IgM-IFA test detected it in only in 0.96% of the samples. The differential toxoplasmosis diagnosis was accomplished with Neospora caninum by IFA, observing 61 (29.2% seropositive animals for this parasite and 149 (70.8% negative. Sixty animals were positive for both T. gondii and N. caninum. Pneumonia, splenomegaly, and intestinal ulcers were macroscopically observed. Unremarkable interstitial pneumonia, enteritis, colitis, splenitis, and glomerulitis were microscopically observed. The immunohistochemical stain could not detect the presence of T. gondii in the tissues of the animals infected experimentally.Detectou-se anticorpos das classes IgG e IgM anti-Toxoplasma gondii em primatas experimentalmente e naturalmente infectados, utilizando-se como técnicas comparativas a RIFI e o ELISA-teste. No grupo dos primatas experimentalmente infectados, anticorpos de valor diagnóstico foram detectados a partir do 9º dia de infecção tanto na RIFI (IgG e IgM como no ELISA-IgG. O ELISA IgM detectou anticorpos a partir do 3º dia de infecção até o final do experimento (102 dias pós-infecção. Dos 209 soros dos primatas naturalmente infectados, de diversos zoológicos do Estado de São Paulo, 64,59 e 67,94% mostraram-se positivos na RIFI-IgG e no ELISA-IgG, respectivamente. O

  14. Determinação da infecção por Entamoeba histolytica em residentes da área metropolitana de Belém, Pará, Brasil, utilizando ensaio imunoenzimático (ELISA para detecção de antígenos Determination of Entamoeba histolytica infection in patients from Greater Metropolitan Belém, Pará, Brazil, by enzyme-linked immunosorbent assay (ELISA for antigen detection

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    Mônica Cristina de Moraes Silva

    2005-06-01

    Full Text Available O status epidemiológico da amebíase está sendo reavaliado desde que a Entamoeba histolytica (patogênica foi considerada espécie distinta de Entamoeba dispar (não patogênica. Em nosso estudo, realizamos pesquisa de antígenos de E. histolytica em amostras fecais de pacientes residentes na cidade de Belém, Pará, Brasil, utilizando ensaio imunoenzimático (E. histolytica Test, TechLab Inc., Blacksburg, Estados Unidos disponível comercialmente. Foram analisadas 845 amostras, com positividade em 248 (29,35%. A infecção por E. histolytica foi maior no grupo etário acima de 14 anos (30,36% que no grupo de 0-14 anos (28,28%, porém sem significância estatística (p The epidemiological status of amebiasis has been reevaluated since Entamoeba histolytica (pathogenic was considered a distinct species from Entamoeba dispar (non-pathogenic. We investigated E. histolytica antigens in stool samples from residents of Belém, Pará State, Brazil, with commercially available enzyme-linked immunosorbent assay (E. histolytica Test, TechLab Inc., Blacksburg, USA. A total of 845 samples were analyzed, of which 248 were positive (29.35%. E. histolytica infection was more frequent in the over-14-year age group (30.36% than in the 0-14-year group (28.28%, but the difference was not statistically significant (p < 0.05. Of all the samples, 334 were also submitted to parasitological methods (direct, Hoffman, and Faust et al.. There were discordant results between ELISA and parasitological methods in 83 samples (24.85%, with more positive results using ELISA. Our results thus suggest that intestinal amebiasis is an important public health problem in Greater Metropolitan Belém.

  15. Cornelius Elisa Bertus Bremekamp

    NARCIS (Netherlands)

    Lanjouw, J.

    1969-01-01

    Cornelis Elisa Bertus Bremekamp was born at Dordrecht on February 7th 1888. He is therefore now just past eighty, and he has been a member of the Koninklijke Nederlandse Botanische Vereniging for sixty years. He studied at the Utrecht State University and, like many of his contemporaries, was

  16. Comparação de kits ELISA® comerciais para anticorpos no soro e leite com um teste coproparasitológico em bovinos naturalmente infectados por Fasciola hepatica Comparison of comercial® ELISA kits for antibodies in serum and milk with a fecal test in cattle naturally infected with Fasciola hepatica

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    Cíntia das C. Bernardo

    2013-01-01

    Full Text Available A fasciolose é uma enfermidade causada por um trematoda que acomete o fígado principalmente de ruminantes domésticos, podendo parasitar o homem e seu diagnóstico é realizado rotineiramente por exames coproparasitológicos. O objetivo do presente estudo foi comparar kits comerciais de ELISA para anticorpos no soro e leite com um teste coproprarasitológico em bovinos naturalmente infectados por Fasciola hepatica. Foram coletadas amostras de fezes (92 sangue (92 e leite (43 de bovinos provenientes de propriedades de gado leiteiro do município de Jerônimo Monteiro, sul do Estado do Espírito Santo. As amostras de fezes coletadas foram processadas pela técnica de sedimentação fecal para ovos de F. hepatica, utilizada como padrão ouro para as análises. Amostras de sangue e de leite foram processadas segundo a orientação do fabricante dos respectivos Kits ELISA comerciais testados. Utilizou-se o c² de McNemar para comparação estatística e calcularam-se a sensibilidade e especificidade, valores preditivos e kappa. Os resultados obtidos mostraram que as frequências de positividade pelo uso dos kits ELISA comerciais de soro e de leite diferiram significativamente (pThe fascioliasis is a disease caused by a trematode that affects the liver mainly of domestic ruminants and can also parasite man; its diagnosis is routinely done by coprological methods. The aim of this study was to compare commercial ELISA kits for antibodies in serum and milk with a coprological test in cattle naturally infected by Fasciola hepatica. We collected fecal, blood and milk samples from cattle in the municipality of Jerônimo Monteiro, southern Espírito Santo state. The fecal samples were processed by the fecal egg sedimentation for F. hepatica, which is used as a gold standard for analyzis. Blood (92 and milk (43 samples were processed according to the manufacturer instructions of the respective commercial ELISA kits tested. We used the McNemar chi-square for

  17. Estandarización de ensayos inmunoenzimáticos (ELISA para la cuantificación de anticuerpos IgG inducidos por una vacuna de vesículas de membrana externa de los serogrupos A y W135 de Neisseria meningitidis

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    Aleida Mandiarote

    2013-04-01

    Full Text Available La enfermedad meningocócica es una afección invasiva, de amplia incidencia mundial, cuyo agente causal es la bacteria gramnegativa Neisseria meningitidis . Existen vacunas polisacarídicas sin conjugar o conjugadas, contra cuatro de los cinco serogrupos responsables del 95% de los casos en el mundo. Para el serogrupo B, cuyo polisacárido es pobremente inmunogénico, se han evaluado varios candidatos vacunales producidos a base de vesículas de membrana externa. La determinación de la actividad bactericida y la cuantificación de IgG por ELISA han sido los métodos más utilizados en la medición de la respuesta inmune generada por vacunas contra la meningitis meningocócica. El segundo de estos métodos es utilizado en el Instituto Finlay como ensayo de inmunogenicidad para la liberación de lotes de VA-MENGOC-BC®. Como parte de una colaboración con investigadores noruegos, se trabaja en la obtención de un candidato vacunal contra los serogrupos A y W135 , basado en vesículas de membrana externa. En el presente trabajo se describe la estandarización de un ELISA para ser utilizado en la evaluación de la respuesta inmune del candidato vacunal bivalente.

  18. Elisa Biagini (Florencia, 1970

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    Berta González Saavedra

    2017-01-01

    Full Text Available Elisa Biagini vive en Italia tras haber estudiado y enseñado en los Estados Unidos durante varios años. Sus poesías han sido publicadas en varias revistas y antologías italianas y americanas, entre otras. Algunas de las más recientes son Nuovissima poesia italiana (Mondadori, 2004 y Parola plurale (Sosselam 2005. Ha publicado siete colecciones poéticas, algunas bilingües, entre las que figuran  L'Ospite (Einaudi, 2004, Fiato. Parole per musica (Edizionidif, 2006, Nel bosco (Einaudi, 2007, The guest in the wood (Chelsea editions, 2013 – 2014 Best Translated Book Award, y la reciente Da una crepa (Einaudi, 2014. Sus poesías han sido traducidas al inglés, español, francés, portugués, japonés, croata, eslovaco, alemán, albanés, ruso, árabe y chino. Ha participado en importantes festivales italianos e internacionales (entre otros, en Italia “Festival della Letteratura” de Mantua, “Festival Poesia” de Parma, “RomaPoesia” de Roma, y en el extranjero “Stanza- Scotland's International Poetry Festival” en St. Andrews, Escocia, “Dubai International Poetry Festival” en Emiratos Árabes Unidos, “PoesieFestivalBerlin” en Berlín, “International Writers Workshop” en Hong Kong, “Struga Poetry Festival” en Struga, Macedonia, “Poetry Parnassus” en Londres, “Printemps des poètes” en Luxemburgo, “Queensland Poetry Festival” en Brisbane, Australia, “Festival Internacional de Poesía de Granada” en Nicaragua, “Xu Zhimo Poetry and Art Festival” en el King's College de Cambridge. Asimismo es traductora de poesía americana y, además de editar algunas colecciones de poetisas americanas contemporáneas, se ha encargado de la edición del volumen Nuovi poeti americani (Einaudi, 2006. Infine, insegna Scrittura Creativa (poesia, Travel Writing e Storia dell'Arte in Italia e all’estero, además de colaborar con artistas visules, coreógrafos y músicos. Entre otras actividades, es artista visual. www.elisabiagini.it

  19. Mobile phone based ELISA (MELISA).

    Science.gov (United States)

    Zhdanov, Arsenii; Keefe, Jordan; Franco-Waite, Luis; Konnaiyan, Karthik Raj; Pyayt, Anna

    2018-04-30

    Enzyme-linked immunosorbent assay (ELISA) is one of the most important technologies for biochemical analysis critical for diagnosis and monitoring of many diseases. Traditional systems for ELISA incubation and reading are expensive and bulky, thus cannot be used at point-of-care or in the field. Here, we propose and demonstrate a new miniature mobile phone based system for ELISA (MELISA). This system can be used to complete all steps of the assay, including incubation and reading. It weighs just 1 pound, can be fabricated at low cost, portable, and can transfer test results via mobile phone. We successfully demonstrated how MELISA can be calibrated for accurate measurements of progesterone and demonstrated successful measurements with the calibrated system. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. ELISA

    Science.gov (United States)

    ... care provider about the meaning of your specific test results. What Abnormal Results ... and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than ...

  1. Avaliação do método imunoenzimático (ELISA para diagnóstico da infecção por Helicobacter pylori em crianças e adolescentes Evaluation of enzyme-linked immunosorbent assay for the diagnosis of Helicobacter pylori infection in children and adolescents

    Directory of Open Access Journals (Sweden)

    Aurea Portorreal

    2002-07-01

    Full Text Available RACIONAL: A infecção por Helicobacter pylori é reconhecida como a causa mais freqüente de gastrite crônica em adultos e crianças. Seu diagnóstico é realizado com métodos invasivos em fragmentos de mucosa gástrica obtidos com pinça endoscópica e os não-invasivos. O método imunoenzimático constitui exame simples, rápido e de baixo custo, apresentando alta sensibilidade em pacientes adultos. OBJETIVO: Avaliou-se o método ELISA prospectivamente em 111 crianças e adolescentes. MATERIAL E MÉTODOS: Utilizou-se o kit "Cobas Core II" (Roche. Considerou-se Helicobacter pylori positivo quando o teste rápido da urease e a histologia resultaram ambos positivos ou quando a cultura foi positiva, e Helicobacter pylori negativo quando todos os testes foram negativos. RESULTADOS: A idade dos 111 pacientes variou de 3 meses a 16 anos, (mediana = 9a 5m; média = 8a 7m ± 4.0. Infecção por Helicobacter pylori foi diagnosticada em 47,7% (53/111. A sensibilidade da sorologia foi de 83,0% e 86,0% e a especificidade foi de 70,6% e 71,0%, utilizando o ponto de corte de 7 U/mL e 5 U/mL, respectivamente. Em pacientes maiores de 10 anos de idade, a sensibilidade foi de 90,6% e 96,8% e a especificidade 71,0% e 61,9%, com ponto de corte de 7 U/mL e 5 U/mL, respectivamente. Quando foi utilizada somente a cultura positiva como padrão ouro e ponto de corte em 5 U/mL, a sensibilidade foi de 93,3%. CONCLUSÃO: O método ELISA apresentou boa sensibilidade em crianças maiores de 10 anos, utilizando o ponto de corte de 5 U/mL, porém a especificidade foi menor.BACKGROUND: Helicobacter pylori infection is recognized as the most frequent cause of chronic gastritis in adults and children. The diagnosis is accomplished with invasive methods in fragments of endoscopic gastric biopsies and non-invasive methods. The enzyme-linked immunosorbent assay constitutes a simple, fast exam and of low cost with high sensibility in adult patients. AIM: The purpose of this study

  2. ELISA-BASE: an integrated bioinformatics tool for analyzing and tracking ELISA microarray data

    OpenAIRE

    White, Amanda M.; Collett, James R.; Seurynck-Servoss, Shannon L.; Daly, Don S.; Zangar, Richard C.

    2009-01-01

    Summary:ELISA-BASE is an open source database for capturing, organizing and analyzing enzyme-linked immunosorbent assay (ELISA) microarray data. ELISA-BASE is an extension of the BioArray Software Environment (BASE) database system.

  3. Canine specific ELISA for coagulation factor VII

    DEFF Research Database (Denmark)

    Knudsen, Tom; Kjelgaard-Hansen, Mads; Tranholm, Mikael

    2011-01-01

    available to date. In this study, a canine specific ELISA for measurement of FVII:Ag in plasma was developed and validated. The FVII:Ag ELISA correctly diagnosed homozygous and heterozygous hereditary FVII deficiency. Together with activity based assays, such as FVII:C, the FVII:Ag ELISA should be valuable...

  4. Elisa technology consolidation study overview

    Science.gov (United States)

    Fitzsimons, E. D.; Brandt, N.; Johann, U.; Kemble, S.; Schulte, H.-R.; Weise, D.; Ziegler, T.

    2017-11-01

    The eLISA (evolved Laser Interferometer Space Antenna) mission is an ESA L3 concept mission intended to detect and characterise gravitational radiation emitted from astrophysical sources [1]. Current designs for eLISA [2] are based on the ESA study conducted in 2011 to reformulate the original ESA/NASA LISA concept [3] into an ESA-only L1 candidate named NGO (New Gravitational Observatory) [4]. During this brief reformulation period, a number of significant changes were made to the baseline LISA design in order to create a more costeffective mission. Some of the key changes implemented during this reformulation were: • A reduction in the inter satellite distance (the arm length) from 5 Gm to 1 Gm. • A reduction in the diameter of the telescope from 40 cm to 20 cm. • A reduction in the required laser power by approximately 40%. • Implementation of only 2 laser arms instead of 3. Many further simplifications were then enabled by these main design changes including the elimination of payload items in the two spacecraft (S/C) with no laser-link between them (the daughter S/C), a reduction in the size and complexity of the optical bench and the elimination of the Point Ahead Angle Mechanism (PAAM), which corrects for variations in the pointing direction to the far S/C caused by orbital dynamics [4] [5]. In the run-up to an L3 mission definition phase later in the decade, it is desirable to review these design choices and analyse the inter-dependencies and scaling between the key mission parameters with the goal of better understanding the parameter space and ensuring that in the final selection of the eLISA mission parameters the optimal balance between cost, complexity and science return can be achieved.

  5. E.L.I.S.A. en coccidioidomicosis humana E.L.I.S.A. in human coccidioidomycosis

    Directory of Open Access Journals (Sweden)

    Iris Nora Tiraboschi

    1991-08-01

    Full Text Available Se realizó E.L.I.S.A. con exoantígeno de Coccidioides immitis para la detectión de anticuerpos, en 67 sueros humanos diluidos 1/1000, 1/2000, 1/4000 y 1/8000. De los 18 sueros de enfermos de coccidioidomicosis comprobada por examen directo, cultivo y/o histología, 5 fueron negativos, en otros 13 fueron positivos en una o varias diluciones. 3/26 sueros de personas sanas, coccidioidino positivas, fueron positivos en títulos de 1/1000 y el resto no tuvo anticuerpos detectables. No presentaron reacciones positivas ninguno de los sueros controles de personas sanas, pero sí lo hicieron 4/8 pacientes con otras micosis. Se concluye que E.L.I.S.A. es útil para la detección de mínimas cantidades de anticuerpos o en sueros que no pueden ser procesados por fijación de complemento. No es recomendable el uso de la técnica en forma aislada por al presencia de reacciones cruzadas.An E.L.I.S.A. test for antibody detection, with an exo-antigen of Coccidioides immitis was standardized in 67 humans sera diluited in 1/1000, 1/2000, 1/4000 and 1/8000. Eightheen sera from mycologically proved cases of coccidioidomycosis were studied: 5 were negative and 13 were positive in some dilutions. 3/26 sera of healthy persons who presented positive skin tests with coccidioidin were positive and the other 23 sera did not have positive reactions. None of the 15 sera of healthy human exhibited positive E.L.I.S.A. Serum samples of 8 patients suffering other deep mycosis were studied, 4 of them presented cross-reactions in E.L.I.S.A. tests. E.L.I.S.A. test seems to be a useful Serologic technique for antibody detection in anticomplementary serum samples or when a low concentration of antibodies should be detected. As it is very sensitive, cross-reactions with other mycoses are frequent, thus the use other more specific serologic technique together E.L.I.S.A. is recommended.

  6. A Simple ELISA Exercise for Undergraduate Biology.

    Science.gov (United States)

    Baker, William P.; Moore, Cathy R.

    Understanding of immunological techniques such as the Enzyme Linked Immuno Sorbent Assay (ELISA) is an important part of instructional units in human health, developmental biology, microbiology, and biotechnology. This paper describes a simple ELISA exercise for undergraduate biology that effectively simulates the technique using a paper model.…

  7. Hyperglucagonaemia analysed by glucagon sandwich ELISA

    DEFF Research Database (Denmark)

    Albrechtsen, Nicolai Jacob Wewer; Hartmann, Bolette; Veedfald, Simon

    2014-01-01

    the extent to which the hyperglucagonaemia measured in clinical samples was caused by authentic glucagon. METHODS: We examined the performance of three commercial glucagon 'sandwich' ELISAs. The ELISA with the best overall performance was selected to compare glucagon measurements in clinical samples...... sensitivity for glucagon in plasma (>10-20 pmol/l). Thus, only the third assay was suitable for measuring glucagon concentrations in clinical samples. The ELISA and RIA measured similar glucagon levels in healthy individuals. Measurements of samples from individuals with abnormally high (type 2 diabetes...... or obese) or very elevated (post vagotomy with pyloroplasty, post-RYGB) glucagon levels were also similar in both assays. However, glucagon levels in participants with ESRD were much lower when measured by ELISA than by RIA, indicating that the apparent hyperglucagonaemia is not caused by fully processed...

  8. Field trial of brucellosis competitive ELISA

    International Nuclear Information System (INIS)

    Perez, B.; Rojas, M.

    1998-01-01

    2990 sera samples from cattle were tested for antibodies to Brucella abortus using 8 serological tests for. The tests used were Rose Bengal (RBT), Buffer Plate Agglutination Test (BPAT), Complement Fixation (CFT), 2 Indirect and 2 Competitive Enzyme Linked Immunosorbent Assays (ELISA). Bacteriological evaluation from milk was done also. All tests were compared with respect to diagnostic specificity in vaccinated herds which were considered to be Brucella-free. The diagnostic specificity of the Indirect and Competitive ELISA was greater than 99,8%. Estimates of relative sensitivity were obtained from infected herds. The diagnostic sensitivity of the Indirect ELISA was greater than 95,8% and for the Competitive ELISA between 98,8 and 100 %, the last value refers to the Competitive ELISA Prototype II (SLPS antigen/M84 Mab), which was found highly suitable to differentiate vaccinated from brucella-infected cattle. The use of C-ELISA II for monitoring bovine populations under an eradication programme is recommended. (author)

  9. SIMPLIFIED DIAGNOSIS OF MALARIA INFECTION: GFM/PCR/ELISA A SIMPLIFIED NUCLEIC ACID AMPLIFICATION TECHNIQUE BY PCR/ELISA

    Directory of Open Access Journals (Sweden)

    Ricardo Luiz Dantas MACHADO

    1998-09-01

    Full Text Available We report an adaptation of a technique for the blood sample collection (GFM as well as for the extraction and amplification of Plasmodium DNA for the diagnosis of malaria infection by the PCR/ELISA. The method of blood sample collection requires less expertise and saves both time and money, thus reducing the cost by more than half. The material is also suitable for genetic analysis in either fresh or stored specimens prepared by this method.Relatamos a adaptação de uma técnica para coleta de amostras (MFV e outra para extração, amplificação de DNA de parasitas da malária para diagnóstico por PCR/ELISA. O método de coleta de amostras requer menos habilidade e economisa tempo e dinheiro, assim reduzindo a mais da metade o custo. O material é também adequado para análise genética em especimens frescos ou estocados, preparados por este método.

  10. Immunodiagnosis of Human Fascioliasis by an Enzyme-Linked Immunosorbent Assay (ELISA) and a Micro-ELISA

    OpenAIRE

    Carnevale, Silvana; Rodríguez, Mónica I.; Santillán, Graciela; Labbé, Jorge H.; Cabrera, Marta G.; Bellegarde, Enrique J.; Velásquez, Jorge N.; Trgovcic, Jorge E.; Guarnera, Eduardo A.

    2001-01-01

    Enzyme-linked immunosorbent assay (ELISA) and micro-ELISA were evaluated for their ability to detect anti-Fasciola hepatica antibodies in humans by using excretory-secretory antigen. The sensitivity of each method was 100%, but the specificity was 100% for ELISA and 97% for micro-ELISA. The micro-ELISA could be used as a screening assay and ELISA could be used as a confirmatory method for the serodiagnosis of human fascioliasis.

  11. Enzyme-Linked Immunosorbent Assay (ELISA).

    Science.gov (United States)

    Konstantinou, George N

    2017-01-01

    Food allergy is a public health concern especially after recognizing its constantly increased prevalence and severity. Despite careful reading of food ingredient statements, food allergic individuals may experience reactions caused by "hidden", "masked", or "contaminated" proteins that are known major allergens. Many techniques have been developed to detect even small traces of food allergens, for clinical or laboratory purposes. Enzyme-linked immunosorbent assay (ELISA) is one of the best validated and most routinely used immunoassay in allergy research, in allergy diagnosis in allergy-related quality control in various industries. Although as a technique it has been implemented for the last 45 years, the evolution in biochemistry allowed the development of ultrasensitive ELISA variations that are capable of measuring quantities in the scale of picograms, rendering ELISA attractive, robust, and very famous.

  12. Specificity of Toxocara ELISA in tropical populations.

    Science.gov (United States)

    Lynch, N R; Wilkes, L K; Hodgen, A N; Turner, K J

    1988-05-01

    The diagnosis of human infection by Toxocara canis relies heavily upon serological tests, the specificity of which can be inadequate in regions of endemic helminthiasis. When different population groups of tropical Venezuela were evaluated using ELISA based upon Toxocara excretory-secretory antigen (TcESA), solid-phase adsorption of the sera with extracts of a wide variety of non-homologous parasites revealed the existence of significant cross-reactivity. This was effectively and conveniently overcome when the test sera were incubated in the presence of the soluble parasite extracts in a competitive inhibition ELISA. The mean reduction of ELISA values caused by pre-adsorption of the sera tested was 32.2%, and that caused by competitive inhibition was 42.3%, the effects of these two procedures being strongly correlated (r = 0.83). The magnitude of the reduction was inversely proportional to the actual ELISA value (r = -0.55), and ranged from a mean of 68.0% in sera from apparently healthy individuals of medium-high socio-economic level, down to 28.1% in heavily parasitized Amazon indians. Ascaris showed the greatest degree of cross-reactivity in these tests, although under conditions of competitive inhibition even sera with high levels of antibody against this parasite could be negative in Toxocara ELISA. Western blotting revealed a major 81,400 D component that was shared between Ascaris and TcESA. Our results indicate that the competitive inhibition of cross-reactivity by soluble non-homologous parasite extracts provides a convenient and economical means of increasing the specificity of ELISA for the determination of the seroprevalence of toxocariasis in tropical populations.

  13. Galactic binaries with eLISA

    OpenAIRE

    Nelemans, G.

    2013-01-01

    I review what eLISA will see from Galactic binaries -- double stars with orbital periods less than a few hours and white dwarf (or neutron star/black hole) components. I discuss the currently known binaries that are guaranteed (or verification) sources and explain why the expected total number of eLISA Galactic binaries is several thousand, even though there are large uncertainties in our knowledge of this population, in particular that of the interacting AM CVn systems. I very briefly sketch...

  14. Radiolinja, Vodafone või Elisa

    Index Scriptorium Estoniae

    2004-01-01

    Jüri Kaljundi, Tarvo Ulejev ning Anne Mere vastavad küsimusele, kas Radiolinja peaks jätma alles olemasoleva nime, võtma nimeks Soomes peagi Radiolinjat asendama hakkava Elisa või rahvusvaheliselt tuntud kaubamärgi Vodafone

  15. Elisa Studio showroom = Elisa Studio showroom / Jan Joonas Graps ; kommenteerinud Tiina Kuusisto

    Index Scriptorium Estoniae

    Graps, Jan Joonas, 1972-

    2015-01-01

    Elisa Studio showroom Helsingis Lasiplatsi, Mannerheimintie 22-24. Sisekujunduse autorid Jan Joonas Graps, Ken-Kristjan Ruut, Anne Määrmann (JanKen Wisespace). Lühidalt loovstuudiost JanKen Wisespace

  16. Development of ELISA kit for rat albumin

    International Nuclear Information System (INIS)

    Yuan Zhigang; Han Shiquan; Liu Yibing; Xu Wenge; Jia Juanjuan

    2009-01-01

    The Anti-rat albumin serum was prepared by immunized the sheep with rat albumin. A ELISA method was established for rat albumin. The measurement range of the assay was 1-50 mg/L, sensitivity of the assay was 0.42 mg/L, recovery rate was 85.0%-106.0%. Intra-and inter-assay variation coefficients were <8.9% and <12.8% respectively. The correlation coefficients between measured and expected values were 0.999 after serial dilution of the urine samples with high concentrations of rat albumin. A good correlation was observed between the ELISA and RIA methods, and the kit for rat albumin might provide a convenience in exploitation of renal drugs and experimental injury of the kidney. (authors)

  17. ELISA technique standardisation for human toxocariasis diagnosis

    International Nuclear Information System (INIS)

    Espinoza, Y.; Suarez, R.; Huiza, A.

    2003-01-01

    To standardise ELISA technique for toxocara canis human infection diagnosis by using excreted-secreted antigen prepared in our country. T. canis eggs were collected by incubation with formalin (2%) at 28 o C in order to obtain third stage larvae that were freed and incubated in RPMI at 37 o C for 7 days; the medium was replaced by a similar one and stored at -20 o C. Antigen was concentrated and protein dosage was made. Sera from patients with toxocariasis and newborns were used as positive and negative controls by ELISA technique, dilutions 1/4 to 1/1024. Polystyrene plates were sensitised with antigen in several concentrations and conjugated peroxidase with horseradish IgG, anti human IgG and substrate OPD were used. Absorbance was read with spectrophotometer (Multiskan plus labsystems) at 492 nm. Cut off point was determined by negative sera absorbencies arithmetic mean plus 3 standard deviations. Antigen concentration was 50 ug/mL, sera dilution 1/128, conjugate dilution 1/1000 with optical density above 0,241. ELISA technique for serologic diagnosis of human infection by toxocara canis could be used in epidemiological studies in our country. Its efficacy will be determined in future studies

  18. Jatobal virus antigenic characterization by ELISA and neutralization test using EIA as indicator, on tissue culture

    Directory of Open Access Journals (Sweden)

    Luiz Tadeu M. Figueiredo

    1988-06-01

    Full Text Available A virus antigenic characterization methodology using an indirect method of antibody detection ELISA with virus-infected cultured cells as antigen and a micro virus neutralisation test using EIA (NT-EIA as an aid to reading were used for antigenic characterization of Jatobal (BeAn 423380. Jatobal virus was characterized as a Bunyaviridae, Bunyavirus genus, Simbu serogroup virus. ELISA using infected cultured cells as antigen is a sensitive and reliable method for identification of viruses and has many advantages over conventional antibody capture ELISA's and other tests: it eliminates solid phase coating with virus and laborious antigen preparation; it permits screening of large numbers of virus antisera faster and more easily than by CF, HAI, or plaque reduction NT. ELISA and NT using EIA as an aid to reading can be applicable to viruses which do not produce cytopathogenic effect. Both techniques are applicable to identification of viruses which grow in mosquito cells.A caracterização antigênica do vírus Jatobal (BeAn 423380 foi efetuada utilizando uma técnica de ELISA para deteccão de anticorpos que utiliza culturas celulares infectadas como antígeno e um micro teste de neutralização para vírus que utiliza o método imunoenzimático como auxiliar para a leitura dos resultados (NT-EIA. O vírus Jatobal foi caracterizado como um Bunyaviridae, gênero Bunyavirus, pertencente ao sorogrupo Simbu. A técnica de ELISA, utilizando culturas celulares infectadas como antígeno, trata-se de método sensível e confiável na identificação de agentes virais, possuindo muitas vantagens sobre ELISA convencionais e outros testes: elimina a preparação laboriosa de antígenos para o revestimento em fase sólida; permite que se teste de forma mais rápida e fácil que por CF, HAI e neutralização por redução de plaques um grande número de antisoros de vírus. ELISA e NT-EIA podem ser utilizados para a classificação de vírus que não produzem

  19. ELISA technique standardization for strongyloidiasis diagnosis

    International Nuclear Information System (INIS)

    Huapaya, P.; Espinoza, I.; Huiza, A.; Universidad Nacional Mayor de San Marcos, Lima; Sevilla, C.

    2002-01-01

    To standardize ELISA technique for human Strongyloides stercoralis infection diagnosis a crude antigen was prepared using filariform larvae obtained from positive stool samples cultured with charcoal. Harvested larvae were crushed by sonication and washed by centrifugation in order to obtain protein extracts to be used as antigen. Final protein concentration was 600 μg/mL. Several kinds of ELISA plates were tested and antigen concentration, sera dilution, conjugate dilution and cut off were determined to identify infection. Sera from patients with both hyper-infection syndrome and intestinal infection demonstrated by parasitological examination were positive controls and sera from people living in non-endemic areas with no infection demonstrated by parasitological examination were negative controls. Best values were 5 μg/mL for antigen, 1/64 for sera, 1/1000 for conjugate; optical density values for positive samples were 1,2746 (1,1065 - 1,4206, DS = 0,3284) and for negative samples 0,4457 (0,3324 - 0,5538, DS = 0,2230). Twenty sera samples from positive subjects and one hundred from negative subjects were examined, obtaining 90% sensitivity and 88% specificity. The results show this technique could be useful as strongyloidiasis screening test in population studies

  20. [Effect evaluation of three ELISA kits in detection of fasciolasis].

    Science.gov (United States)

    Ai, Lin; Chen, Mu-Xin; Chen, Shao-Hong; Chu, Yan-Hong; Cai, Yu-Chun; Zhou, Xiao-Nong; Chen, Jia-Xu

    2013-04-01

    To evaluate the effect of 3 ELISA kits on detection of human fasciolasis. Twenty-six serum samples from patients with fasciolasis, 180 serum samples from patients with other parasitic diseases as well as 26 serum samples from healthy people were detected by ELISA kits which using soluble antigen of Fasciola gigantica, Fasciola hepatica (Fg-ELISA and Fh-ELISA) as well as IgG antigen ELISA detection kits made by DRG company in Germany. The effects of the 3 kits were evaluated. The sensitivities of Fg-ELISA, Fh-ELISA, and DRG-ELISA were 100.0%, 80.8% (95% CI: 65.7%-95.9%) and 100.0%, respectively; the specificities of the three were 87.9% (95% CI: 83.5%-92.4%), 85.0%(95% CI: 80.1%-89.9%) and 83.5% (95% CI: 78.4%-88.6%), respectively, and Youden indexes of them were 0.88, 0.66 and 0.84, respectively. The detection rate of Fg-ELISA (100%) was significantly higher than that of Fh-ELISA (80.8%) (P DRG-ELISA for clinical sample tests as well as massive screening in fasciolasis endemic areas in southwest China.

  1. Mycotoxin determination using RIA and ELISA methods

    Energy Technology Data Exchange (ETDEWEB)

    Fukal, L; Sova, Z

    1985-12-01

    Experience is summed up of various authors with the determination of some mycotoxins (aflatoxin, ochratoxin A, T-2 toxin, rubratoxin, zearalenon, sterigmatocystine) using radioimmunoassay and enzyme immunoassay. For RIA purposes, tritium or sometimes iodine 125 is frequently used for labelling mycotoxins. Mycotoxins do not show immunogenic properties and must thus be conjugated with a high-molecular compound (serum albumin, polylysine) prior to immunozation. Factors are discussed making mycotoxin determination in foods difficult. Specificity of the obtained antisera is total between the individual mycotoxin groups while cross reactions are always recorded within the groups. RIA makes it possible to determine down to 200 pg (labelled with /sup 3/H) or 5 pg (labelled with /sup 125/I) of mycotoxins in a standard solution. In addition to high sensitivity and specificity, immunoassays of mycotoxins minimize the quantities of samples and solvents needed for extraction. Large series of samples can be processed using automatic analyzers. ELISA generally is more advantageous than RIA.

  2. LISA Pathfinder and eLISA news

    Science.gov (United States)

    Thorpe, James Ira; Mueller, Guido

    2014-01-01

    Two important gatherings of the space-based gravitational-wave detector community were held in Zurich, Switzerland this past March. The first was a meeting of the Science Working Team for LISA Pathfinder (LPF), a dedicated technology demonstrator mission for a future LISA-like gravitational wave observatory. LPF is entering an extremely exciting phase with launch less than 15 months away. All flight components for both the European science payload, known as the LISA Technology Package (LTP), and the NASA science payload, known as the Space Technology 7 Disturbance Reduction System (ST7-DRS), have been delivered and are undergoing integration. The final flight component for the spacecraft bus, a cold-gas thruster based on the successful GAIA design, will be delivered later this year. Current focus is on completing integration of the science payload (see Figures 1 and 2) and preparation for operations and data analysis. After a launch in Summer 2015, LPF will take approximately 90 days to reach its operational orbit around the Earth-Sun Lagrange point (L1), where it will begin science operations. After 90 days of LTP operations followed by 90 days of DRS operations, LPF will have completed its prime mission of paving the way for a space-based observatory of gravitational waves in the milliHertz band. Immediately following the meeting of the LPF team, the eLISA consortium held its third progress meeting. The consortium (www.elisascience.org) is the organizing body of the European space-based gravitational-wave community, and it was responsible for the "The Gravitational Universe" whitepaper that resulted in the November 2013 election of a gravitational-wave science theme for ESA's Cosmic Visions L3 opportunity. In preparation for an L3 mission concept call, which is expected later this decade, and for launch in the mid 2030s, the eLISA consortium members are coordinating technology development and mission study activities which will build on the LPF results. The final

  3. A chromogranin A ELISA absent of an apparent high-dose hook effect observed in other chromogranin A ELISAs.

    Science.gov (United States)

    Erickson, J Alan; Grenache, David G

    2016-01-15

    Routine testing for chromogranin A (CgA) using an established commercial ELISA revealed an apparent high-dose hook effect in approximately 15% of specimens. Investigations found the same effect in two additional ELISAs. We hypothesized that a CgA derived peptide(s) at high concentrations was responsible but experiments were inconclusive. Here we describe the analytical performance characteristics of the Chromoa™ CgA ELISA that did not display the apparent high-dose hook effect. Performance characteristics of the Chromoa ELISA were assessed. The reference interval was established utilizing healthy volunteers. Specimens producing the apparent high-dose hook effect in other assays were evaluated using the Chromoa ELISA. The limit of detection was 8ng/ml. Linearity was acceptable (slope=1.04, intercept=18.1 and r(2)=0.997). CVs were ≤4.6 and ≤9.3% for repeatability and within-laboratory imprecision, respectively. CgA was stable at ambient and refrigerated temperatures for a minimum of two and 14days, respectively. An upper reference interval limit of 95ng/ml was established. Specimens demonstrating the apparent high-dose hook effect in other ELISAs did not exhibit the phenomenon using the Chromoa ELISA. The Chromoa ELISA demonstrates acceptable performance for quantifying serum CgA. The apparent high-dose hook effect exhibited in other ELISAs was absent using the Chromoa assay. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. (ELISA) kit for diagnosis copro-antigens of Giardia lamblia

    African Journals Online (AJOL)

    STORAGESEVER

    2010-08-02

    Aug 2, 2010 ... methods based on antigen scanning of parasites such as enzyme linked immunosorbent assay (ELISA), ... samples. To design this method, a pure antibody against parasite as well as an antibody conjugated to a ..... school children in Santiago, Chile by capture ELISA for the detection of fecal Giardia ...

  5. Agricultural production - Phase 2. Indonesia. ELISA for epidemiology of brucellosis

    International Nuclear Information System (INIS)

    Sutherland, S.S.

    1992-01-01

    This document is a travel report of a three-week mission (from October 13 to November 1, 1991) to Indonesia within the framework of ''The implementation of ELISA technology for the sero-diagnosis of important livestock diseases''. The mission evaluated the implementation of ELISA technology at the Regional Laboratories and its role in the surveillance and control of bovine brucellosis

  6. Multi-Laboratory Validation of Estrone (E1) ELISA Methods

    Science.gov (United States)

    This project is a round-robin evaluation of commercially available Enzyme-Linked Immunosorbent Assay (ELISA) technology to quantitatively or qualitatively measure the hormone estrone (E1) in combined animal feeding operation (CAFO) receiving streams. ELISA is meant to be a simpl...

  7. DETERMINATION OF HISTAMINE IN FISH USING ELISA TECHNIQUE

    NARCIS (Netherlands)

    KRUGER, C; SEWING, U; STENGEL, G; KEMA, [No Value; WESTERMANN, J; MANZ, B

    1995-01-01

    The analysis of histamine in fish and fish products via competitive ELISA is described. The advantages of this method are easy sample preparation and handling, screening capabilities, and low costs. Automation enables the performance of the assay with higher series of samples. The Histamine-ELISA is

  8. AN ELISA ASSAY FOR HEME OXYGENASE (HO-1)

    Science.gov (United States)

    An ELISA assay for heme oxygenase (HO-l ) Abstract A double antibody capture ELISA for the HO-l protein has been developed to separately quantitate HO-I protein. The use of 2.5% NP40 detergent greatly assists in freeing HO-l protein from membranes and/or other cel...

  9. SENSIBILIDAD DE INMUNOIMPRESIÓN-ELISA Y DAS-ELISA EN EL DIAGNÓSTICO Y MUESTREO DEL VIRUS DE LA TRISTEZA DE LOS CÍTRICOS EN HUERTOS COMERCIALES DE TAMAULIPAS, MEXICO

    Directory of Open Access Journals (Sweden)

    N. Ruiz-García

    2009-01-01

    Full Text Available El Virus de la tristeza de los cítricos (VTC causa una enfermedad de interés regulatorio para la citricultura mexicana. El diagnóstico y un muestreo oportuno y confiable es esencial para aplicar estrategias de manejo ante el avance en territorio nacional del pulgón café, su principal vector. Con el fin de contar con un método eficaz y eficiente para el muestreo y detección del VTC, se evaluó el desempeño del método de inmunoimpresión-ELISA con respecto a DAS-ELISA, el método oficial de diagnóstico, debido a su economía, facilidad y rapidez. Con este propósito se evaluaron 7,421 árboles, considerando la edad del brote y de infección, provenientes de 11 huertos comerciales de Tamaulipas. El método de inmunoimpresión-ELISA superó en sensibilidad y capacidad de pronóstico de positivos a DAS-ELISA en el diagnóstico de árboles con infección reciente o desconocida del VTC (P¿0.028. La disposición de brotes positivos en el dosel fue heterogénea siendo descrita por la función beta binomial (P¿0.16-0.23. Con base en esta función y la reproducción de los resultados de impresiones dobles por pecíolo (93.2 % se sugiere un tamaño óptimo de muestra de 10 pecíolos por árbol en impresiones simples. Este método fue 54.9 % más económico que DAS-ELISA y los diagnósticos se realizaron en una sexta parte del tiempo requerido en esta última prueba. Sin embargo, por el requerimiento de la norma oficial mexicana vigente (NOM- 031-FITO-2000, se recomienda el método de inmunoimpresión-ELISA como un método rápido para discriminar árboles positivos en muestreos de campo que deben posteriormente ser verificados por el método oficial de diagnóstico.

  10. Frequency of antiphospholipid antibodies in patients with infectious diseases using three different ELISA methods Freqüência de anticorpos antifosfolípides em pacientes com doenças infecciosas usando três diferentes testes de ELISA

    Directory of Open Access Journals (Sweden)

    Mittermayer Barreto Santiago

    2006-02-01

    anticorpos anticardiolipina (aCL é o mais importante teste para o diagnóstico da síndrome antifosfolipídica (SAF. Entretanto esse teste também pode ser positivo em algumas doenças infecciosas. Tem sido sugerido que a detecção de anticorpos para uma mistura de fosfolípides ou para beta2-glicoproteína I (beta2-GP I teria uma maior especificidade para a SAF que o teste de ELISA-padrão para aCL. O objetivo do presente estudo é comparar a especificidade de três testes para anticorpos antifosfolípides (aFL em pacientes com doenças infecciosas. MÉTODOS: Anticorpos antifosfolípides foram pesquisados por três técnicas de ELISA, ou seja, o teste-padrão para aCL, o kit de ELISA APhL® e o teste para anti-beta2-GP I em pacientes com doenças infecciosas, tais como sífilis (69, leptospirose (33 e Calazar (30. RESULTADOS: A freqüência de positividade de aFL da classe IgG em pacientes com sífilis, leptospirose e Calazar foi de 13/69 (19%, 9/33 (27% e 2/30 (6%, respectivamente, com o ELISA-padrão para aCL versus 1/69 (1,4%, 0/33 (0% e 0/30 (0% com o kit de ELISA APhL®. A positividade do isotipo IgM foi de 10/69 (14%, 4/33 (12% e 1/30 (3%, respectivamente, com o ELISA-padrão para aCL, e 1/69 (1,4%, 0/33 (0% e 0/30 (0% com o kit de ELISA APhL®. Anticorpos da classe IgG contra beta2GPI foram detectados em 14/69 casos de sífilis (20%, 6/33 casos de leptospirose (18% e 16/30 casos de Calazar (53%. Assim, o kit de ELISA APhL® apresentou uma maior especificidade: 97% (95% CI: 92%-99% comparado com 81% (95% CI: 74%-87% para o teste de aCL-padrão e 72% (95% CI: 64%-79% para o teste de anticorpos anti-beta2 GPI. CONCLUSÕES: O kit de ELISA APhL® parece ser mais específico para a SAF que o ELISA-padrão para aCL, assim como o teste para anti-beta2GPI. Esse kit pode ser usado para ajudar no diagnóstico e na confirmação da SAF.

  11. Analysis of fenbendazole residues in bovine milk by ELISA.

    Science.gov (United States)

    Brandon, David L; Bates, Anne H; Binder, Ronald G; Montague, William C; Whitehand, Linda C; Barker, Steven A

    2002-10-09

    Fenbendazole residues in bovine milk were analyzed by ELISAs using two monoclonal antibodies. One monoclonal antibody (MAb 587) bound the major benzimidazole anthelmintic drugs, including fenbendazole, oxfendazole, and fenbendazole sulfone. The other (MAb 591) was more specific for fenbendazole, with 13% cross-reactivity with the sulfone and no significant binding to the sulfoxide metabolite. The limit of detection of the ELISA method in the milk matrix was 7 ppb for MAb 587 and 3 ppb for MAb 591. Fenbendazole was administered in feed, drench, and paste form to three groups of dairy cattle. Milk was collected immediately before dosing and then every 12 h for 5 days. The ELISA indicated that residue levels varied widely among individual cows in each group. Fenbendazole levels peaked at approximately 12-24 h and declined rapidly thereafter. Metabolites were detected at much higher levels than the parent compound, peaked at approximately 24-36 h, and declined gradually. Residue levels were undetectable by 72 h. The ELISA data correlated well with the total residues determined by chromatographic analysis, but the use of the two separate ELISAs did not afford an advantage over ELISA with the single, broadly reactive MAb 587. The ELISA method could be used to flag high-residue samples in on-site monitoring of fenbendazole in milk and is a potential tool for studying drug pharmacokinetics.

  12. Comparison of dot-ELISA and standard ELISA for detection of Neisseria meningitidis outer membrane complex-specific antibodies

    Directory of Open Access Journals (Sweden)

    Elza FT Belo

    Full Text Available Dot-ELISA using the outer membrane complex antigens of Neisseria meningitidis as a target was standardized for rapid detection of meningococcal-specific antibodies in human serum. We investigated the level of meningococcal-specific IgG, IgA, and IgM in serum using dot-ELISA with outer membrane antigens prepared from Neisseria meningitidis serotype B:4.19:P1.15,3,7,9 (a strain isolated from a Brazilian epidemic. The dot-ELISA is based on the same principles as the standard ELISA and is useful for detection of anti-N. meningitidis B antibodies in serum of patients with meningococcal infections. For the assay, outer membrane complexes (OMCs were absorbed by nitrocellulose membrane and blocked with a 5% skim milk solution. Serum samples were drawn upon hospital admission and during convalescence from patients with meningococcal septicemia, and single samples were drawn from uninfected controls. We retrospectively examined a total of 57 serum samples: 35 from patients infected with N. meningitidis B, 12 from patients infected with Haemophilus influenzae b, and 10 from health individuals. When performed at room temperature, dot-ELISA took approximately four hours to perform, and the optimum antigen concentration was 0.42 µg per dot. The specificity of IgG, IgM, and IgA demonstrates that dot-ELISA using OMCs from N. meningitidis B as a target is suitable for serologic verification of clinically suspected meningococcal disease in patients and for titer determination of antibodies produced during different phases of natural infection. Furthermore, the sensitivity of dot-ELISA was comparable to that of standard ELISA. Overall, dot-ELISA is simple to perform, rapid, and low cost. Further validation of the test as a screening tool is required.

  13. Grantee Spotlight: Elisa Rodriguez, Ph.D., M.S.

    Science.gov (United States)

    Dr. Elisa M. Rodriguez tests the feasibility of community-based participatory research approaches to engaging Hispanics, African Americans, and the medically underserved in the Buffalo, NY area in biospecimen donation for cancer research.

  14. Determinación de Glifosato mediante inmunoensayo enzimático (ELISA en el Paisaje Protegido Laguna de Rocha y su entorno, Uruguay.

    Directory of Open Access Journals (Sweden)

    Daniela Nardo

    2015-12-01

    Full Text Available En el entorno de la Laguna de Rocha se ha visto incrementada la superficie dedicada a las actividades agrícolas con un mayor uso de plaguicidas, entre ellos el herbicida glifosato, usado en cultivos de soja principalmente. Mediante la utilización de técnicas de inmunoensayo enzimático (ELISA, se investigó la presencia de glifosato en la Laguna y algunos de sus afluentes en dos momentos específicos de tiempo. Se detectó glifosato en 27 de las 28 muestras estudiadas. Muestras positivas por ELISA fueron confirmadas por cromatografía iónica. El método ELISA demostró ser una herramienta de screening adecuada para determinar la presencia de glifosato en agua.

  15. Direct Competitive Enzyme-Linked Immunosorbent Assay (ELISA).

    Science.gov (United States)

    Kohl, Thomas O; Ascoli, Carl A

    2017-07-05

    The competitive enzyme-linked immunosorbent assay (ELISA) (cELISA; also called an inhibition ELISA) is designed so that purified antigen competes with antigen in the test sample for binding to an antibody that has been immobilized in microtiter plate wells. The same concept works if the immobilized molecule is antigen and the competing molecules are purified labeled antibody versus antibody in a test sample. Direct cELISAs incorporate labeled antigen or antibody, whereas indirect assay configurations use reporter-labeled secondary antibodies. The cELISA is very useful for determining the concentration of small-molecule antigens in complex sample mixtures. In the direct cELISA, antigen-specific capture antibody is adsorbed onto the microtiter plate before incubation with either known standards or unknown test samples. Enzyme-linked antigen (i.e., labeled antigen) is also added, which can bind to the capture antibody only when the antibody's binding site is not occupied by either the antigen standard or antigen in the test samples. Unbound labeled and unlabeled antigens are washed away and substrate is added. The amount of antigen in the standard or the test sample determines the amount of reporter-labeled antigen bound to antibody, yielding a signal that is inversely proportional to antigen concentration within the sample. Thus, the higher the antigen concentration in the test sample, the less labeled antigen is bound to the capture antibody, and hence the weaker is the resultant signal. © 2017 Cold Spring Harbor Laboratory Press.

  16. An ELISA test for the detection of antibodies to Legionella pneumophila.

    OpenAIRE

    Wreghitt, T G; Nagington, J; Gray, J

    1982-01-01

    An enzyme-linked immunosorbent assay (ELISA) test has been developed to detect antibodies to Legionella pneumophila serogroup 1. There is good correlation between indirect fluorescent antibody (IFA) and ELISA titres but ELISA is more sensitive.

  17. Teste de ELISA indireto para o diagnóstico sorológico de pitiose Indirect ELISA for the serodiagnostic of pythiosis

    Directory of Open Access Journals (Sweden)

    Janio M. Santurio

    2006-03-01

    Full Text Available A pitiose, doença granulomatosa de eqüinos causada pelo oomiceto Pythium insidiosum, tem como característica a evolução rápida seguida de morte dos animais. Estas mortes muitas vezes são causadas por diagnósticos errôneos ou demorados quando os doentes já não respondem ao tratamento. Este trabalho teve por objetivo a padronização do ensaio imunoenzimático indireto (ELISA para diagnóstico sorológico de pitiose em eqüinos e coelhos, visando a diminuição de erros e de tempo necessário para o diagnóstico. Para o desenvolvimento e validação do teste foram utilizadas 72 amostras de soro de eqüinos saudáveis e 44 soros de eqüinos com pitiose confirmada. Os resultados da validação do ELISA para eqüinos foram: sensibilidade 97,72%, especificidade 90,27%, valor preditivo positivo 86%, valor preditivo negativo 98,4% e eficiência de 93,1%. Para coelhos, o teste foi padronizado com 48 amostras de soro de animais saudáveis e 24 amostras de coelhos imunizados com antígenos de P. insidiosum. Os resultados foram: sensibilidade 91,66%, especificidade 95,83%, valor preditivo positivo 91,66%, valor preditivo negativo 95,83% e eficiência de 94,44%. Os resultados deste trabalho demonstram que o ensaio imunoenzimático indireto é um método seguro e eficaz para o diagnóstico sorológico da pitiose.Pythiosis is a granulomatous disease caused by the oomycete Pythium insidiosum that affects humans and animals, especially horses. Deaths are very often the consequence of incorrect or late diagnosis when animals no longer respond to treatment. This study aimed standardization of the ELISA assay for the serodiagnostic of pythiosis in horses and rabbits, in order to minimize errors and delays in the diagnosis of the disease. Sera of 72 healthy and 44 of by pythiosis affected horses were used for development and evaluation of the test. The ELISA for equine diagnostic showed 97.72% sensitivity, 90.27% specificity, 86% positive predictive value

  18. A new ELISA for determination of potency in snake antivenoms.

    Science.gov (United States)

    Rial, A; Morais, V; Rossi, S; Massaldi, H

    2006-09-15

    A competitive ELISA for potency determination of bothropic equine antivenom was developed and compared to the conventional in vivo ED(50) assay, with the aim of partially substituting the in vivo assay in the monitoring of antivenom immunoglobulin levels. On this purpose, blood samples were taken at different times during and after the immunization protocol of the lot of horses used for production of snake antivenom at the Instituto de Higiene, Uruguay. Both the competitive ELISA and the ED(50) assay were performed on those samples. In addition, a group of five commercial pepsin-digested antivenoms were tested by both methods. A significant (P<0.001) correlation (Pearson's r=0.957) was found between the ELISA titres and the corresponding ED(50) values, indicating that the in vitro test can estimate the neutralizing antibody capacity of the sera as well as the in vivo assay. By means of this new ELISA, it was found that the immunized animals maintained good venom antibody titres, in the order of 20-50% of the maximum achieved, even 10 month after the end of the immunization schedule. The main advantage of our ELISA design is its ability to correctly estimate the neutralization capacity of crude hyperimmune plasma and antivenom sera independently of their antibody composition in terms of whole IgG or F(ab')(2) fragment.

  19. ELISA reader does not interfere by mobile phone radiofrequency radiation

    Science.gov (United States)

    Mortazavi, Seyyed Mohammad Javad; Baradaran-Ghahfarokhi, Hamid Reza; Abdi, Mohammad Reza; Baradaran-Ghahfarokhi, Milad; Mostafavi, Nayyer Sadat; Mahmoudi, Golshan; Berenjkoub, Nafiseh; Akmali, Zahra; Hossein-Beigi, Fahimeh; Arsang, Vajiheh

    2016-01-01

    Background: The increasing number of mobile phones can physically cause electromagnetic interference (EMI) in medical environments; can also cause errors in immunoassays in laboratories. The ELISA readers are widely used as a useful diagnostic tool for Enzymun colorimetric assay in medicine. The aim of this study was to investigate whether the ELISA reader could be interfered by the exposure to the 900 MHz cell phones in the laboratory. Materials and Methods: Human serum samples were collected from 14 healthy donors (9 women and 5 men) and each sample was divided into four aliquots and was placed into four batches for the in-vitro quantitative determination of human chorionic gonadotropin (hCG). During colorimetric reading of the first, second, and third batches, the ELISA reader (Stat Fax 2100, Awareness Technology, Inc., USA) was exposed to 0.5, 1.0, and 2.0 W exposure of 900 MHz radiation, respectively. For the forth batch (control group), no radiation was applied. All experiments were performed comparing ELISA read out results of the I, II, and III batches with the control batch, using the Wilcoxon test with criterion level of P = 0.050. Results: The final scores in the exposed batches I, II, and III were not statistically significant relative to the control batch (P > 0.05). The results showed that 900 MHz radiation exposure did not alter the ELISA measured levels of hCG hormone in I (P = 0.219), II (P = 0.909), and III (P = 0.056) batches compared to the control batch. Conclusion: This study showed that ELISA reader does not interfere by mobile phone RF radiation at a closed contact (less than 5 cm distance). However, we recommend that medical institutions discuss these issues in the context of their specific use of technologies and frame a policy that is clear and straightforward to guide staff, patients, and visitors. PMID:27376040

  20. Evaluation of SD BIOLINE H. pylori Ag rapid test against double ELISA with SD H. pylori Ag ELISA and EZ-STEP H. pylori Ag ELISA tests.

    Science.gov (United States)

    Negash, Markos; Kassu, Afework; Amare, Bemnet; Yismaw, Gizachew; Moges, Beyene

    2018-01-01

    Helicobacter pylori antibody titters fall very slowly even after successful treatment. Therefore, tests detecting H. pylori antibody lack specificity and sensitivity. On the other hand, H. pylori stool antigen tests are reported as an alternative assay because of their reliability and simplicity. However, the comparative performance of H. pylori stool antigen tests for detecting the presence of the bacterium in clinical specimens in the study area is not assessed. Therefore, in this study we evaluated the performance of SD BIOLINE H. pylori Ag rapid test with reference to the commercially available EZ- STEP ELISA and SD BIOLINE H. pylori Ag ELISA tests. Stool samples were collected to analyse the diagnostic performance of SD BIOLINE H. pylori Ag rapid test kit using SD H. pylori Ag ELISA kit and EZ- STEP ELISA tests as a gold standard. Serum samples were also collected from each patient to test for the presence of H. pylori antibodies using dBest H. pylori Test Disk. Sensitivity, specificity, predictive values and kappa value are assessed. P values H. pylori Ag rapid test were: 95.6% (95% CI, 88.8-98.8), 92.5% (95%CI, 89-94.1%), 86.7% (95% CI, 80.5-89.6), and 97.6% (95% CI, 993.9-99.3) respectively. The performance of SD BIOLINE H. pylori Ag rapid test was better than the currently available antibody test in study area. Therefore, the SD BIOLINE Ag rapid stool test could replace and be used to diagnose active H. pylori infection before the commencement of therapy among dyspeptic patients.

  1. Comparative evaluation of competitive ELISA test in Colombian cattle

    International Nuclear Information System (INIS)

    Marino, O.; Rueda, E.; Sedano, L.; Zuniga, I.; Calderon, C.; Ortega, A.; Puentes, A.

    1998-01-01

    In order to contribute to the definition of the best ELISA test for screening and differential diagnosis of Brucella abortus to be applied for control programmes, a total of 2971 sera from Colombian cattle were tested for brucellosis. Conventional agglutination tests, Buffered Plate antigen test (BPAT) and Rose Bengal (RB) as well as Complement Fixation test (CFT) (Alton, et al. 1988) were used comparatively. Radial immunodiffusion test (RID) was also performed to all sera. The sera were also tested using four different ELISAs: indirect ELISA from FAO/IAEA and the indirect ELISA modified by Nielsen, et al. 1992 as well as two competitive ELISAs: one competitive ELISA used B. abortus O-polysaccharide antigen and an enzyme conjugated monoclonal to the O-polysaccharide for competition and detection. The second competitive ELISA used lipopolysaccharide (sLPS) antigen, a different monoclonal antibody for competition but also specific for the O-polysaccharide and a commercially available goat anti-mouse IgG enzyme conjugate for detection. The sera were analyzed based on its population status, 987 positive obtained from Brucella abortus infected herds based on clinical and/or bacteriological evidence and a high prevalence of brucellosis, CFT percentage of positive animals in the herd was greater than 5%. Eight hundred sixty six (866) negative sera from non-vaccinated cattle from a brucellosis free area and 1118 negative sera obtained from reglamentary vaccinated areas under a free herd program. Initial cut-off values were derived using negative serum samples. The diagnostic sensitivity and specificity was defined from frequency histograms based on this cut-off values and using 2x2 tables, corresponding confidence limits (95%) were calculated. The data were also analysed using signal detection analysis (ROC). Kappa statistics was determined for all tests and populations, accuracy was used as index of comparison to evaluate different assays. The data support the initial

  2. An ELISA for the quantitation of von Willebrand Factor

    DEFF Research Database (Denmark)

    Vinholt, Pernille Just; Overgaard, Martin; Diederichsen, Axel Cosmus Pyndt

    2013-01-01

    for measurement of von Willebrand factor-osteoprotegerin complex (VWF:OPG) in human plasma. Furthermore, the significance of VWF:OPG complex as a marker of cardiovascular disease (CVD) was evaluated. PATIENTS/METHODS: A sandwich ELISA for quantification of VWF:OPG was developed using a polyclonal rabbit anti...... with and without documented coronary calcification (total n=118). RESULTS AND CONCLUSIONS: The assay detected VWF:OPG complexes in human plasma, while no significant signal was observed when testing solutions containing VWF or recombinant OPG alone. Importantly, the ELISA assay was able to detect in vitro formed...

  3. Evaluation of monoclonal antibody-based sandwich direct ELISA (MSD-ELISA for antigen detection of foot-and-mouth disease virus using clinical samples.

    Directory of Open Access Journals (Sweden)

    Kazuki Morioka

    Full Text Available A monoclonal antibody-based sandwich direct ELISA (MSD-ELISA method was previously developed for foot-and-mouth disease (FMD viral antigen detection. Here we evaluated the sensitivity and specificity of two FMD viral antigen detection MSD-ELISAs and compared them with conventional indirect sandwich (IS-ELISA. The MSD-ELISAs were able to detect the antigen in saliva samples of experimentally-infected pigs for a longer term compared to the IS-ELISA. We also used 178 RT-PCR-positive field samples from cattle and pigs affected by the 2010 type-O FMD outbreak in Japan, and we found that the sensitivities of both MSD-ELISAs were about 7 times higher than that of the IS-ELISA against each sample (P<0.01. In terms of the FMD-positive farm detection rate, the sensitivities of the MSD-ELISAs were about 6 times higher than that of the IS-ELISA against each farm (P<0.01. Although it is necessary to conduct further validation study using the other virus strains, MSD-ELISAs could be appropriate as a method to replace IS-ELISA for FMD antigen detection.

  4. Evaluation of monoclonal antibody-based sandwich direct ELISA (MSD-ELISA) for antigen detection of foot-and-mouth disease virus using clinical samples.

    Science.gov (United States)

    Morioka, Kazuki; Fukai, Katsuhiko; Sakamoto, Kenichi; Yoshida, Kazuo; Kanno, Toru

    2014-01-01

    A monoclonal antibody-based sandwich direct ELISA (MSD-ELISA) method was previously developed for foot-and-mouth disease (FMD) viral antigen detection. Here we evaluated the sensitivity and specificity of two FMD viral antigen detection MSD-ELISAs and compared them with conventional indirect sandwich (IS)-ELISA. The MSD-ELISAs were able to detect the antigen in saliva samples of experimentally-infected pigs for a longer term compared to the IS-ELISA. We also used 178 RT-PCR-positive field samples from cattle and pigs affected by the 2010 type-O FMD outbreak in Japan, and we found that the sensitivities of both MSD-ELISAs were about 7 times higher than that of the IS-ELISA against each sample (P<0.01). In terms of the FMD-positive farm detection rate, the sensitivities of the MSD-ELISAs were about 6 times higher than that of the IS-ELISA against each farm (P<0.01). Although it is necessary to conduct further validation study using the other virus strains, MSD-ELISAs could be appropriate as a method to replace IS-ELISA for FMD antigen detection.

  5. Elisa development for detection of glyphosat resistant gm soybean

    Directory of Open Access Journals (Sweden)

    Владислав Геннадійович Спиридонов

    2015-11-01

    Full Text Available During research we have utilized recombinant enzyme 5-enolpyruvylshikimate-3-phosphate synthase (CP4 EPSPS, conferring resistance to glyphosate for GM soybean, for the hen immunization and obtaining specific yolk antibodies IgY. Stages of ELISA development that can detect at least 0,1 % of GM-soybean resistant to glyphosate were present

  6. Detection of antibodies to the 20s proteasome by ELISA

    DEFF Research Database (Denmark)

    Jørgensen, Karin Meinike; Frederiksen, Jette Lautrup; Nielsen, Christoffer Tandrup

    2013-01-01

    The presence of antibodies against the 20S proteasome has been correlated with diseases like multiple sclerosis (MS) and systemic lupus erythematosus (SLE) but no definite association has been established. In order to investigate this further, we optimized an ELISA for proteasome antibodies...

  7. An experiment to test in-field pointing for Elisa

    Science.gov (United States)

    Brugger, Christina; Broll, Bernhard; Fitzsimons, Ewan; Johann, Ulrich; Jonke, Wouter; Lucarelli, Stefano; Nikolov, Susanne; Voert, Martijn; Weise, Dennis; Witvoet, Gert

    2017-11-01

    The evolved Laser Interferometer Space Antenna (eLISA) Mission is being developed to detect and characterise gravitational waves by measuring pathlength changes between free flying inertial test masses over a baseline of order 1 Gm. Here the observed astrophysical events and objects lie in a frequency range between 30 μHz and 1 Hz (the LISA measurement band, LMB).

  8. Opportunities and challenges when pooling milk samples using ELISA

    DEFF Research Database (Denmark)

    Græsbøll, Kaare; Andresen, Lars Ole; Hisham Beshara Halasa, Tariq

    2017-01-01

    -positive samples by pooling. To illustrate this, the sensitivity of antibody ELISA on pooled samples of bovine milk for Salmonella Dublin, Mycobacterium avium spp. paratuberculosis, and bovine virus diarrhea was tested. For these milk assays, the analytical sensitivity decreased rapidly with increasing pool sizes...

  9. ELISA reader does not interfere by mobile phone radiofrequency radiation

    Directory of Open Access Journals (Sweden)

    Seyyed Mohammad Javad Mortazavi

    2016-01-01

    Conclusion: This study showed that ELISA reader does not interfere by mobile phone RF radiation at a closed contact (less than 5 cm distance. However, we recommend that medical institutions discuss these issues in the context of their specific use of technologies and frame a policy that is clear and straightforward to guide staff, patients, and visitors.

  10. A novel indirect ELISA for diagnosis of dengue fever

    Directory of Open Access Journals (Sweden)

    Rohan Narayan

    2016-01-01

    Full Text Available Background & objectives: Dengue fever (DF is associated with significant morbidity and mortality in the tropical and sub-tropical regions of the world. Since there are no effective antiviral drugs for treatment, clinicians often rely on the accurate diagnosis of dengue fever to begin supportive therapy at early stages of the illness. The objective of this study was to develop an in-house dengue virus serotype 2 (DENV-2 non-structural protein- 5 (NS5 based indirect ELISA. Methods: DENV-2 was raised in Vero cells and the viral proteins were separated and subsequently the NS5 protein was eluted. Serum samples from primary and secondary dengue fever patients; and acute and convalescent samples from Japanese encephalitis (JE and West Nile virus (WNV cases were used to validate the ELISA. Results: The assay was found to be 100 per cent specific in detecting DENV-2 specific antibodies from patient′s serum. However, in terms of sensitivity, the assay could detect IgM antibodies only from 90 per cent of the primary dengue samples. The IgM/IgG ratio of the primary and secondary samples was 7.24 and 0.64, respectively. Interpretation & conclusions: The results indicate that the DENV-2 NS5 ELISA is dengue group specific and can be used to differentiate dengue infection from other circulating Flavivirus infections. This NS5 ELISA can also be used to distinguish between primary and secondary dengue fever on the basis of IgM/IgG ratios. Further studies with larger sample sizes and different DENV serotypes are required to validate the ELISA.

  11. Toxoplasma gondii antibodies sheep in Lages, Santa Catarina, Brazil, and comparison using IFA and ELISA Anticorpos toxoplásmicos em ovinos de Lages, Santa Catarina, Brasil, e comparação utilizando RIFI e ELISA

    Directory of Open Access Journals (Sweden)

    Francine Bragagnolo Liz Stefen Sakata

    2012-09-01

    Full Text Available Toxoplasmosis in sheep is a disease of great importance in veterinary medicine, which causes economic losses in livestock and has a great impact on human health, since consumption of infected meat facilitates transmission of zoonotic infections. Blood samples from sheep (n = 360 were collected from 13 farm properties in the municipality of Lages, Santa Catarina, to estimate the prevalence of toxoplasmosis and identify risk factors associated with Toxoplasma gondii infection. T. gondii, antibodies were investigated by means of the indirect immunofluorescence assay (IFA and enzyme-linked immunosorbent assay (ELISA. Animals infected with T. gondii were found on 100% of the farms. IFA detected 56.9% (205/360 and ELISA 42.5% of the infected sheep. Breed was the only risk factor associated with the presence of T. gondii antibodies. ELISA showed sensitivity of 61%, specificity of 82% and kappa of 0.41, which was considered moderate. This allows use of ELISA as an alternative technique for diagnosing T. gondii in sheep.A toxoplasmose ovina é uma doença parasitária de elevada importância em medicina veterinária e em saúde pública, acarretando prejuízos na produção animal, gerados pelas perdas reprodutivas e econômicas, além de sua implicação na saúde humana, já que o consumo de carne infectada facilita a transmissão zoonótica. Para determinar a prevalência e identificar fatores de risco para a infecção por T. gondii em ovinos de Lages, Santa Catarina, amostras de sangue (n = 360 foram coletadas em 13 propriedades. Cada criador respondeu a um questionário para permitir a identificação dos fatores de risco da infecção. A pesquisa de anticorpos foi realizada por meio da Reação de Imunofluorescência Indireta (RIFI > 64 e do Ensaio Imunoenzimático Indireto (ELISA. Em 100% das propriedades foram encontrados animais positivos. Pela RIFI, 205 (56,94% ovinos apresentaram anticorpos contra T. gondii e pelo ELISA, 153 (42

  12. Comparison of indirect ELISA based on recombinant protein NcSRS2 and IFAT for detection of Neospora caninum antibodies in sheep Comparação entre ELISA baseado no antígeno recombinante NcSRS2 e RIFI para detecção de anticorpos de Neospora caninum em ovinos

    Directory of Open Access Journals (Sweden)

    Renato Andreotti

    2009-06-01

    Full Text Available Neospora caninum, an Apicomplexan parasite that can causes abortion, is responsible for considerable economic and reproductive losses in livestock. The purpose of the present study was to determine whether recombinant NcSRS2 is a suitable indirect ELISA antigen for determining specific immune response to N. caninum in sheep. A total of 441 serum samples were subjected to IFAT and rNcSRS2 based-ELISA, with both tests performing similarly. The sensitivity and specificity of indirect ELISA were 98.6 and 98.3%, respectively. The kappa index shows 0.98 concordance between the two tests, which is considered excellent. Seroprevalences of 30.8 and 32.0% were detected by IFAT and indirect ELISA, respectively, showing these tests did not differ significantly on this measure (p > 0.05. Serological analysis showed that HisG tag was detected by Western Blotting recognizing rNcSRS2 protein. The potential value of rNcSRS2-based ELISA as a highly specific and sensitive tool for serological diagnosis is also supported by the strong agreement found between IFAT and ELISA. The results support the potential use of recombinant protein NcSRS2 as an antigen in indirect ELISA in sheep.Neospora caninum é um parasito Apicomplexa que pode causar abortos e é reconhecido como agente importante responsável por perdas econômicas e reprodutivas. Este estudo avaliou a proteína recombinante NcSRS2 como antígeno para ELISA indireto na determinação de resposta imune para N. caninum em ovinos. 441 amostras de soro foram analisadas por IFAT e ELISA indireto com rNcSRS2 e ambos os testes revelaram comportamento similar. A sensibilidade e especificidade de ELISA indireto foram 98,6 e 98,3%, respectivamente. O índice kappa mostrou uma concordância entre os dois testes com valor de 0,98, que é considerado excelente. Prevalências de 30,8 e 32,0% detectadas por IFAT e ELISA indireto, respectivamente, mostraram que os testes não diferiram significativamente nesse aspecto (P

  13. Measles serodiagnosis: standardization and evaluation of a dot-ELISA Diagnóstico sorológico do sarampo: padronização e avaliação do teste Dot-ELISA

    Directory of Open Access Journals (Sweden)

    Lourdes R. A. Vaz de Lima

    1994-04-01

    Full Text Available A Dot-ELISA using a measles virus (MV antigen obtained by sodium deoxycholate treatment was standardized and evaluated for IgM and IgG antibody detection in measles patients and measles-vaccinated subjects. A total of 192 serum samples were studied, comprising 47 from patients with acute and convalescent measles, 55 from 9-month old children prior to measles vaccination and 41 from children of the same age after vaccination, and 49 from patients with unrelated diseases. The diagnostic performances of the IgG Dot-ELISA and IgG immuno fluorescence test (IFT were found to be close, varying from 0.97 to 1.00 in sensitivity and the specificities were maximum (1.00. Nevertheless, the sensitivity of the IgM Dot-ELISA (0.85 was higher than that (0.63 of the IgM IFT, although both assays had comparably high (1.00 specificities. The IgM Dot-ELISA in particular proved to be more sensitive in relation to other assays studied by revealing antibodies in 80.0% (12/15 of vaccinated children on the 15th day after immunization. In contrast the IgM IFT, failed to detect antibodies in the same group of vaccinated children. The stability of the MV antigen was longer than that of the IFT antigen, and the reproducibility of the Dot-Elisa was satisfactory.A técnica de Dot-ELISA (DE para detecção de anticorpos IgM e IgG anti vírus do sarampo foi padronizada e avaliada utilizando-se antígeno viral obtido por tratamento com desoxicolato de sódio (DOC. Foram estudadas 192 amostras de soros, compreendendo 47 amostras de 22 pacientes com sarampo nas fases aguda e convalescente, 55 amostras de soros de crianças antes da vacinação, tendo 9 meses de idade, 41 amostras de soros de crianças da mesma idade colhidas após vacinação e 49 amostras de soros de pacientes com outras patologias. O desempenho diagnóstico da técnica de Dot-ELISA-IgG foi semelhante ao de Imunofluorescência indireta (IFI IgG cujos índices de sensibilidade variaram de 0,97 a 1,00 e os de

  14. DEVELOPMENT AND STANDARDIZATION OF AN INDIRECT ELISA FOR THE DIAGNOSIS MAEDI-VISNA IN SHEEP DESENVOLVIMENTO E PADRONIZAÇÃO DE UM ELISA INDIRETO PARA DIAGNÓSTICO DE MAEDI VISNA EM OVINOS

    Directory of Open Access Journals (Sweden)

    Tânia Valeska Medeiros Dantas

    2008-04-01

    Full Text Available The objective of this work was to develop and standardize an indirect ELISA for diagnosis of Maedi Visna (MV infection. The antigen was produced from the supernatants of caprine synovial membrane (CSM cell monolayers inoculated with Maedi Visna virus (MVV, strain K1514, by cycles of freezing and thawed, and clarified by centrifugation at 3000 g for 40 min. The clarified suspension was precipitated with PEG 8000 and centrifugated at 12000 g for 60 min; the pellet was resuspended in buffer TNE and layered onto a sucrose cushion by centrifugation at 42000 g for 105 min. The pellet was resuspended in PBS containing phenylmethylsulphonyl fluoride (PMSF. The ELISA was performed in 96 wells plates, incubated for 1 h at 37 ºC. The reaction was detected by incubation with the enzyme substrate and o-phenylenediamine (OPD during 15 min.  The tests were compared using 175 sera samples. The concentration of the antigen was 2 µg/mL and the best dilution of the sera was 1:100. ELISA detected more positive samples (22.9% than AGID (6.3% and presented a better sensitivity than AGID and, although the specificity was below the expected, it could already be recomended in the diagnosis of MVV infection.KEY WORDS: ELISA, MaediVisna, serologic diagnosis, sheep lentivirus. O objetivo deste trabalho foi desenvolver e padronizar um ELISA indireto para diagnóstico de Maedi Visna (MV. Produziu-se o antígeno em sobrenadantes de cultivo celular de membrana sinovial caprina (MSC inoculado com o Maedi Visna Vírus (MVV cepa K1514, que passou por ciclos de congelamento e descongelamento, sendo logo após clarificado

  15. Efficacy demonstration of tetanus vaccines by double antigen ELISA.

    Science.gov (United States)

    Rosskopf, U; Noeske, K; Werner, E

    2005-09-01

    This paper describes a double antigen ELISA (DAE) for rapid, specific and reliable assessment of the antitetanus immune status of horses and sheep. Compared with the indirect ELISA, the double antigen ELISA has the advantage of species-independent testing of sera. Thanks to its test design, it is more specific since the detected antibodies are forced to bind tetanus toxoid twice. In addition, it is very sensitive to tetanus antibodies, enabling the detection of low antibody titres, in range which is relevant for the assessment of the protective status (tetanus toxin neutralising antibodies). The detection limit of the DAE for tetanus antibodies is in the order of 10(-4) EU/ml. A comparison of in vitro results of individual sera with in vivo titres showed that horse sera with titres of 0.04 and 0.05 EU/ml in the DAE showed titres of > 0.05 IU and 0.034 IU/ml respectively during in vivo testing thus indicating good agreement. For tested sheep sera which were rated > 0.05 IU/ml in vivo, the corresponding titre in the DAE was 0.24 EU/ml. Clear tetanus antitoxin establishment of protective ELISA limits requires further comparative examination of sera with low titres (tetanus vaccines ad us. vet. As a consequence, the toxin neutralisation test (still being the standard method of choice for quantifying tetanus toxin neutralising antitoxin titres) could be replaced, since it requires too great a number of animals per test and involves considerable suffering for the animals. The test described here reduces the use of mice and guinea pigs within vaccine efficacy testing. In addition, it involves less exposure of the laboratory personnel to toxin.

  16. Purification, characterization and ELISA detection of mink immunoglobulins

    DEFF Research Database (Denmark)

    Martel, Cyril Jean-Marie; Aasted, Bent

    2008-01-01

    the estimated molecular weights of the immunoglobulin gamma, alpha and mu heavy chains were found to be 54 kDa, 69 kDa and 83 kDa respectively. The purities of purified IgG, IgM and IgA were estimated by immunoglobulin class specific ELISAs to be more than 90% for IgG and IgM, and more than 80% for IgA....

  17. ELISA techniques for the determination of methanogenic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Bryniok, D; Troesch, W [Fraunhofer-Institut fuer Grenzflaechen- und Bioverfahrenstechnik (IGB), Stuttgart (Germany, F.R.)

    1989-12-01

    Easy-to-handle enzyme-linked immunosorbent assay (ELISA) techniques have been developed suitable for quantitative species-specific determination of very low numbers of methanogens in complex bacterial populations. The amount and the distribution of different species of methanogens in anaerobic digestors is a reflection of the functional status of the degradation process; this can be recognized with these tests and hence may be used for process control. (orig.).

  18. Detección de anticuerpos contra Trypanosoma cruzi en Somoto, Nicaragua, mediante ELISA indirecto e IFI en muestras de sangre en papel de filtro

    Directory of Open Access Journals (Sweden)

    Palacios Xiomara

    2000-01-01

    Full Text Available Se estandarizó un inmunoensayo enzimático en fase sólida (ELISA para estudiar la presencia de anticuerpos contra Trypanosoma cruzi en personas asintomáticas que viven en un área endémica de enfermedad de Chagas en Nicaragua. El ensayo fue estandarizado para el análisis de muestras de sangre colectadas en papel de filtro como método simple de transporte de muestras de sangre. Se realizó un estudio previo en el que se estudiaron por ELISA 18 muestras de suero total y 18 eluidos de sangre de pacientes con enfermedad de Chagas crónica, 30 muestras de suero y 30 eluidos de sangre de personas sanas que se utilizaron como controles negativos y 14 muestras de suero y 14 eluidos de sangre de pacientes con leishmaniasis cutánea o visceral que se utilizaron para los estudios de reacciones cruzadas. Tanto con el suero total como con los eluidos de sangre, la prueba de ELISA proporcionó una sensibilidad de 100% y una especificidad de 90%; solo se observaron reacciones cruzadas con las muestras de pacientes con leishmaniasis visceral. El estudio poblacional incluyó a ocho comunidades rurales de Somoto, Nicaragua. Mediante un muestreo al azar se colectaron muestras de sangre en papel de filtro a 2 434 personas (1 335 del sexo masculino y 1 099 del sexo femenino de las comunidades de Aguas Calientes, La Manzana, Los Canales, Santa Rosa, Las Playas, El Brocal, Santa Isabel y Santa Teresa. Las muestras fueron estudiadas por ELISA e inmunofluorescencia indirecta (IFI encontrándose un total de 260 seropositivos por ELISA (10,7%, 207 de los cuales fueron también positivos por IFI (8,5%. La mayoría de los sueros seropositivos correspondieron a personas del sexo femenino con ambas técnicas, pero la diferencia entre hombres y mujeres no fue estadísticamente significativa. Los resultados obtenidos con ambas técnicas mostraron una excelente concordancia. Con respecto a la edad se observó una curva ascendente, con 5,4% de seropositivos por ELISA en

  19. Influence of affinity on antibody determination in microtiter ELISA systems

    International Nuclear Information System (INIS)

    Peterman, J.H.; Voss, E.W. Jr.; Butler, J.E.

    1986-01-01

    Theoretically, all immunoassays are affinity (Ka) dependent when the product of the antibody (Ab) Ka and the free epitope concentration is less than 10. Thus, the degree of dependence on Ka depends on the concentration of available antigen in the system. The authors examined the binding of 125 I-anti-fluorescein (a-FLU) monoclonal antibodies of different affinities to FLU-gelatin adsorbed on Immunlon 2 microtiter plates. Data obtained were in general agreement with our theoretical predictions; the percent of 125 I-a-FLU which bound correlated with Ka, as did the shape of the titration curves. Measurement of 5 a-FLU monoclonals by the ELISA showed that the determination of Ab concentrations depends on the FLU-gelatin concentration, epitope density, and on the relationship between the Kas of test samples and the reference standard Ab preparation. Thus the ELISA is Ka dependent and should not be used routinely to estimate the absolute amount to Ab in unknown samples. However, the Ka dependency of the ELISA might provide a convenient assay for the estimation of the relative functional Ka (rfKa) of antibody preparations

  20. Quantitative sandwich ELISA for the determination of fish in foods.

    Science.gov (United States)

    Faeste, Christiane K; Plassen, Christin

    2008-01-01

    Allergy to fish represents one of the most prevalent causes for severe food-allergic reactions. Therefore, food authorities in different countries have implemented mandatory labeling of fish in pre-packed foods. Detection of fish proteins in food has previously been based on the use of patient serum. In the present study, a novel sandwich enzyme-linked immunosorbent assay (ELISA) for the quantitation of fish in food matrixes has been developed and validated, using a polyclonal rabbit anti-cod parvalbumin antibody for capture and a biotinylated conjugate of the same antibody for detection. By employing the ubiquitous muscle protein parvalbumin as target the method succeeds to detect a variety of fish. However, the ELISA is specific for fish and does not cross-react with other species. Recoveries ranged from 68-138% in typical food matrixes, while the intra- and inter-assay precisions were parvalbumin ELISA with a limit of detection of 0.01 mg parvalbumin/kg food, about 5 mg fish/kg food, seems sufficient to detect fish protein traces in foods at levels low enough to minimize the risk for fish allergic consumers.

  1. Indirect Competitive Enzyme-Linked Immunosorbent Assay (ELISA).

    Science.gov (United States)

    Kohl, Thomas O; Ascoli, Carl A

    2017-07-05

    The indirect competitive ELISA (indirect cELISA) pits plate-immobilized antigen against antigens in solution for binding to antigen-specific antibody. The antigens in solution are in the test sample and are first incubated with antigen-specific antibody. These antibody-antigen complexes are then added to microtiter plates whose wells have been coated with purified antigen. The wells are washed to remove unbound antigen-antibody complexes and free antigen. A reporter-labeled secondary antibody is then added followed by the addition of substrate. Substrate hydrolysis yields a signal that is inversely proportional to antigen concentration within the sample. This is because when antigen concentration is high in the test sample, most of the antibody is bound before adding the solution to the plate. Most of the antibody remains in solution (as complexes) and is thus washed away before the addition of the reporter-labeled secondary antibody and substrate. Thus, the higher the antigen concentration in the test sample, the weaker the resultant signal in the detection step. The indirect cELISA is often used for competitive detection and quantification of antibodies against viral diseases in biological samples. © 2017 Cold Spring Harbor Laboratory Press.

  2. Modification the ELISA Kit for diagnosis of “Pseudomonas aeruginosa and comparing it with ordinary ELISA kit”

    Directory of Open Access Journals (Sweden)

    Taghreed A. Mohammad

    2017-07-01

    Full Text Available The first aim of the present study was to diagnosis Pseudomonas  aeruginosa by many tests. This study consisted "200 patients " who suffered from burn wound and compare with 100 health individuals (male and female as a control group, Vitek test was used to diagnose  118 (87 "local isolate  ATCC 15692" with 31 other isolate of Pseudomonas  aeruginosa  ((ATCC 15690, ATCC 15688  from 200 samples which were taken from burn patients. This result was similar to Analytical profile index ( API   test (118 isolates of  P. aeruginosa with 82 isolations of  other bacteria. Then the detection P. aeruginosa isolate  ATCC 15692 by new ELISA Technique and comparing its with modify the ordinary ELISA kit.

  3. A noise simulator for eLISA: Migrating LISA Pathfinder knowledge to the eLISA mission

    OpenAIRE

    Armano, M.; Audley, H.; Auger, G.; Baird, J.; Binetruy, P.; Born, Michael; Bortoluzzi, D.; Brandt, N.; Bursi, A.; Caleno, M.; Cavalleri, A.; Cesarini, A.; Cruise, M.; Danzmann, Karsten; Diepholz, I.

    2015-01-01

    We present a new technical simulator for the eLISA mission, based on state space modeling techniques and developed in MATLAB. This simulator computes the coordinate and velocity over time of each body involved in the constellation, i.e. the spacecraft and its test masses, taking into account the different disturbances and actuations. This allows studying the contribution of instrumental noises and system imperfections on the residual acceleration applied on the TMs, the latter reflecting the ...

  4. Methodology for determination of plasma cortisol in fish using Competitive Enzyme-Linked Immunosorbent Assay (ELISA)

    DEFF Research Database (Denmark)

    Velasco-Santamaría, Yohana M.; Cruz-Casallas, Pablo E.

    2007-01-01

    Objective. To determine plasma cortisol procedure in fish using competitive enzymelinked immunosorbent assay (ELISA). Materials and methods. Two plasma samples of juveniles rainbow trout Oncorhynchus mykiss were analized by using ELISA human kit for cortisol assay. For standard curve calibration...

  5. Rapid enzyme-linked immunosorbent assay (ELISA) for Aspergillus fumigatus antibodies.

    OpenAIRE

    Richardson, M D; Stubbins, J M; Warnock, D W

    1982-01-01

    A rapid enzyme-linked immunosorbent assay (ELISA) where component incubation periods were shortened to one hour, was compared with agar gel double diffusion (AGDD) and a standard ELISA procedure for detecting antibodies to Aspergillus fumigatus in 28 asthmatic patients with suspected allergic aspergillosis. Using two A fumigatus antigens the rapid ELISA compared well with AGDD and the standard ELISA method. Eleven sera that reacted with both antigens in AGDD were all positive against antigen ...

  6. Detection of toxoplasma-specific immunoglobulin G in human sera: performance comparison of in house Dot-ELISA with ECLIA and ELISA.

    Science.gov (United States)

    Teimouri, Aref; Modarressi, Mohammad Hossein; Shojaee, Saeedeh; Mohebali, Mehdi; Zouei, Nima; Rezaian, Mostafa; Keshavarz, Hossein

    2018-05-08

    In the current study, performance of electrochemiluminescence immunoassay (ECLIA) in detection of anti-toxoplasma IgG in human sera was compared with that of enzyme-linked immunosorbent assay (ELISA). Furthermore, performance of an in house Dot-ELISA in detection of anti-toxoplasma IgG was compared with that of ECLIA and ELISA. In total, 219 human sera were tested to detect anti-toxoplasma IgG using Dynex DS2® and Roche Cobas® e411 Automated Analyzers. Discordant results rechecked using immunofluorescence assay (IFA). Then, sera were used in an in house Dot-ELISA to assess toxoplasma-specific IgG. Of the 219 samples, two samples were found undetermined using ECLIA but reactive using ELISA. Using IFA, the two sera were reported unreactive. Furthermore, two samples were found reactive using ECLIA and unreactive using ELISA. These samples were reported reactive using IFA. The overall agreement for the two former methods was 98% (rZ0.98.1; P house Dot-ELISA included sensitivity of 79.5, specificity of 78.2, and accuracy of 78.9%, compared to ECLIA and ELISA. Positive and negative predictive values included 82.9 and 74.2%, respectively. A 100% sensitivity was found in in house Dot-ELISA for highly reactive sera in ECLIA and ELISA. ECLIA is appropriate for the first-line serological screening tests and can replace ELISA due to high speed, sensitivity, and specificity, particularly in large laboratories. Dot-ELISA is a rapid, sensitive, specific, cost-effective, user-friendly, and field-portable technique and hence can be used for screening toxoplasmosis, especially in rural fields or less equipped laboratories.

  7. Evaluación del rendimiento diagnóstico de técnicas ELISA para la Enfermedad de Chagas en Colombia

    OpenAIRE

    Caicedo DIaz, Ricardo Andrés

    2017-01-01

    Introducción: La enfermedad de Chagas es producida por el Trypanosoma cruzi, endémica en América Latina. El diagnóstico es complejo, lo cual constituye una barrera al acceso actualmente. El método recomendado por la OMS en fase crónica es una combinación de dos pruebas inmunoserológicas con diferentes configuraciones antigénicas. El procedimiento actual en Colombia es la tamización con una ELISA y la confirmación con una IFI. Objetivo: Evaluar el rendimiento diagnóstico de siete pruebas de...

  8. Comparison of DOT-ELISA and Standard-ELISA for Detection of the Vibrio cholerae Toxin in Culture Supernatants of Bacteria Isolated from Human and Environmental Samples.

    Science.gov (United States)

    Meza-Lucas, Antonio; Pérez-Villagómez, María-Fernanda; Martínez-López, José-Patricio; García-Rodea, Ricardo; Martínez-Castelán, María-Guadalupe; Escobar-Gutiérrez, Alejandro; de-la-Rosa-Arana, Jorge-Luis; Villanueva-Zamudio, Altagracia

    2016-09-01

    A comparison of DOT-ELISA and Standard-ELISA was made for detection of Vibrio cholerae toxin in culture supernatants of bacteria isolated from human and environmental samples. A total of 293 supernatants were tested in a double blind assay. A correlation of 100 % was obtained between both techniques. The cholera toxin was found in 20 Inaba and 3 Ogawa strains. Positive samples were from seafood (17 samples), potable water (1 sample) and sewage (5 samples). The DOT-ELISA was useful as the standard-ELISA to confirm the presence of cholera toxin in the environmental samples.

  9. The Diagnostic Value of ELISA Method for Pertussis in Children

    Directory of Open Access Journals (Sweden)

    O. P. Popova

    2016-01-01

    Full Text Available Because of low effectiveness of laboratory methods for diagnosing pertussis it is important to look for new ways of verification of this infection. The article presents the analysis of the diagnostic value of ELISA method, which involves the identification of antibodies of different isotypes (IgM, IgG, IgA to pertussis toxoid (PT and filamentous haemagglutinin (FHA. The study included 279 children: 114 were under 1 year of age, 165 — older than 1 year. The pertussis was confirmed in 74.3 ± 2.6% of patients by using ELISA method. A significant proportion of seronegative patients (46.1 ± 6.2 per cent was revealed in the group of patients under 1 year. The pattern of production of antibodies in unvaccinated children was different. It depended on the age of the children and timing of illness. A low proportion of diagnostically significant indicators of IgM-antibodies at 2—3 weeks of illness was typical for patients under 1 year of age (e.g. 6.7 ± 6.5% as compared to 20.0 ± 7.9% and 50.0 ± 15.3 — 1—3 and 4—6 years of age. The diagnosis of pertussis in children under 1 year of age was confirmed mainly by the detection of IgG, starting from the 4th week of the disease. In the examination of vaccinated children diagnostically significant levels of IgA and IgG were identified (even in the late stages of the disease. Thus, the results of the analysis show special significance of using ELISA method for the diagnosis of pertussis in vaccinated children.

  10. Elisa Live -palvelu : Laajentuminen Ison-Britannian markkinoilla

    OpenAIRE

    Heimolinna, Rami

    2016-01-01

    Tämän opinnäytetyön tarkoituksena oli tuottaa Elisan liiketoimintatiimille tietoa, joka liittyy Elisa Live -palvelun vuonna 2015 alkaneeseen kansainväliseen laajentumiseen. Työn tavoitteita olivat asiakasymmärryksen lisääminen ja tiedon kerääminen Elisan kilpailijoista valitussa myyntikanavassa Amazon-verkkokaupassa. Teoriaosuudessa selvitettiin kilpailutekijöitä, markkinointiviestintää ja kansainvälistymistä. Nykytilanneanalyysissä tutkittiin Isoa-Britanniaa markkina-alueena ja Amazon-ve...

  11. Rubella virus detection by ELISA method in exposed radiation workers

    International Nuclear Information System (INIS)

    Wu Jianmei; Zhu Bo; Zhu Youming; Shao Jinhui; Wu Weiping; Han Jinxiang

    2005-01-01

    Objective: A rapid diagnosis method was developed to detect Rubella virus infection in radiation workers. Methods: Modified ELISA method was used to detect the level of lgG and lgM antibodies in 514 in Jinan district. Results: 90.47% of 514 cases was shown to be resistant against Rubella virus; 6.42% were sensitive type; 0.78% belonged to be reinfected. Conclusion: Detection of Rubella virus in exposed radiation workers was imperative, and vaccine against Rubella virus was also needed to eliminate the infection risk. (authors)

  12. Evaluation Of Antibody Elisa, Coproscopy And Serum Enzyme ...

    African Journals Online (AJOL)

    Le titrage avec immunoadsorbant lié à une enzyme (ELISA), la sédimentation fécale et les tests de l'action de l'enzyme du sérum ont été faits sur des échantillons de fèces et de sérum recueillis de 134 bovins (55 positifs et 79 négatifs pour les lésions dues à la douve du foie) lors de l'inspection de viande en Ethiopie.

  13. Evaluation of antibody responses in american visceral leishmaniasis by ELISA and immunoblot Avaliação da resposta imune humoral na leishmaniose visceral americana pelos métodos ELISA e "immunoblot"

    Directory of Open Access Journals (Sweden)

    Thomas G. Evans

    1989-06-01

    indivíduos controles. Apenas um dos 72 controles, que tinha um irmäo com leishmaniose visceral, apresentou positividade para o teste. "Immunoblots" de soros de pacientes apresentaram bandas múltiplas, sendo as mais freqüentes de aproximadamente 116 kDa, 70 kDa. Com menor freqüência foram observadas bandas de 93 kDa, 74 kDa, 62 kDa, 46 kDa e 32 kDa. As respostas, através de ELISA e dos padröes de separaçäo por "immunoblot", foram distintas na leishmaniose visceral e podem ser usadas para diferenciar pacientes com leishmaniose visceral daqueles com doenças de Chagas ou leishmaniose cutânea. As amostras sorológicas de pacientes acompanhados durante seis semanas após o tratamento näo apresentaram nenhuma banda nova. A eletroforese em gel de poliacrilamida-sulfato de dodecil de sódio (SDS-PAGE das proteínas iodinadas da superfície do parasita mostrou uma banda principal e quatro menores, enquanto a eletroforese de proteínas biotiniladas do parasita mostrou um padräo semelhante aquele apresentado pelos soros dos pacientes. A leishmaniose visceral parece produzir um padräo de "immunoblot" característico que pode ser usado, juntamente com um método sensível tipo ELISA, no diagnóstico de leishmaniose visceral americana.

  14. ELISA, a demonstrator environment for information systems architecture design

    Science.gov (United States)

    Panem, Chantal

    1994-01-01

    This paper describes an approach of reusability of software engineering technology in the area of ground space system design. System engineers have lots of needs similar to software developers: sharing of a common data base, capitalization of knowledge, definition of a common design process, communication between different technical domains. Moreover system designers need to simulate dynamically their system as early as possible. Software development environments, methods and tools now become operational and widely used. Their architecture is based on a unique object base, a set of common management services and they host a family of tools for each life cycle activity. In late '92, CNES decided to develop a demonstrative software environment supporting some system activities. The design of ground space data processing systems was chosen as the application domain. ELISA (Integrated Software Environment for Architectures Specification) was specified as a 'demonstrator', i.e. a sufficient basis for demonstrations, evaluation and future operational enhancements. A process with three phases was implemented: system requirements definition, design of system architectures models, and selection of physical architectures. Each phase is composed of several activities that can be performed in parallel, with the provision of Commercial Off the Shelves Tools. ELISA has been delivered to CNES in January 94, currently used for demonstrations and evaluations on real projects (e.g. SPOT4 Satellite Control Center). It is on the way of new evolutions.

  15. Inmunodiagnóstico de la fasciolosis humana en la provincia de Chupaca-Junin, mediante un ELISA de captura basado en cistatina

    Directory of Open Access Journals (Sweden)

    William Cornejo

    2003-12-01

    Full Text Available OBJETIVO: Determinar la prevalencia de fasciolosis humana en un área endémica mediante un inmunoensayo enzimático (ELISA que emplea la cistatina como agente de captura para la detección de anticuerpos específicos para cisteinil proteinasas de Fasciola hepatica. MATERIAL Y MÉTODOS: Una placa de ELISA fue sensibilizada con cistatina, incubada con los productos de excreción-secreción del parásito adulto, seguido del procedimiento estándar para la prueba. La aplicación del ELISA de captura para el inmunodiagnóstico de la fasciolosis consideró el estudio de 200 muestras de suero de niños y adultos de la provincia de Chupaca, en el departamento de Junín. RESULTADOS: Las muestras de suero provenientes de una población endémica evaluada por la prueba de ELISA de captura revelaron 27/200 (13,5% casos positivos. CONCLUSIÓN: La fasciolosis constituye un problema de salud importante en la provincia de Chupaca, departamento de Junín.

  16. Celulitis por citomegalovirus

    Directory of Open Access Journals (Sweden)

    A. Ruiz Lascano

    2002-12-01

    Full Text Available Las lesiones cutáneas por citomegalovirus (CMV son infrecuentes y a menudo una manifestación tardía de una enfermedad sistémica, que generalmente anuncia un curso fatal. Comunicamos un caso de celulitis por CMV: una mujer de 70 años con trasplante renal efectuado 1 mes antes de la consulta, terapia inmunosupresora con ciclosporina A y metilprednisona. La paciente ingresó por fiebre, dolor e impotencia funcional en pierna derecha. Comprobamos la existencia de una placa de 8 por 4 cm eritematoedematosa. La tratamos con antibióticos sin mejoría, por lo que realizamos un estudio histopatológico de piel que mostró cambios citopáticos compatibles con infección por CMV. Los cultivos bacteriológicos y micológicos fueron negativos. La inmunohistoquímica específica para CMV y el estudio de reacción en cadena de la polimerasa (PCR de la biopsia de piel fueron positivas, al igual que la antigenemia. El tratamiento con ganciclovir produjo la mejoría del cuadro clínico. En la literatura revisada no hemos encontrado la celulitis como manifestación de enfermedad cutánea por CMV.

  17. The Electron Cyclotron Resonance Light Source Assembly of PTB - ELISA

    CERN Document Server

    Gruebling, P; Ulm, G

    1999-01-01

    In the radiometry laboratory of the Physikalisch-Technische,Bundesanstalt at the Berlin electron storage ring BESSY I, radiation sources for radiometric applications in industry and basic research in the vacuum ultraviolet (VUV) spectral range are developed, characterized and calibrated. Established sources such as deuterium lamps, Penning and hollow cathode discharge sources have limited spectral ranges and in particular their stability and life time suffers from the erosion of the cathode material. To overcome these limitations we have developed a radiation source based on the principle of the electron cyclotron resonance ion source. ELISA is a 10 GHz monomode source with a compact design featuring a tunable cavity and axially positionable permanent magnets. The radiation emission of the source can be detected simultaneously in the VUV and X-ray spectral range via a toroidal grating monochromator and a Si(Li)-detector. The special design of the source allows spectroscopic investigations of the plasma in dep...

  18. ELISA for Detection of Soya Proteins in Meat Products

    Directory of Open Access Journals (Sweden)

    Eva Renčová

    2009-01-01

    Full Text Available Indirect competitive ELISA method for the detection of soya proteins in meat products was developed. The detection limit of the method is 0.5% of the weight of added soya protein. A total of 131 meat product samples such as salamis or sausages from the Czech Republic market were investigated for the presence of soya proteins. Soya proteins were detected in 84% of the investigated samples without any declaration on the package of the product. The use of vegetable additives, namely soya in meat products in the market of the Czech Republic is very frequent and the restriction of its usage by legislation relates only to some kinds of durable products and ham (Act 264/2003 Coll.. The need for sensitive inspecting methods for soya protein detection is not only associated with the economic aspect (adulteration, but mainly with consumer health protection in case of allergy to soya proteins.

  19. Enzyme-linked immunosorbent assay (ELISA for measles antibody: a comparison with haemagglutination inhibition, immunofluorescence and plaque neutralization tests Reação imunoenzimática (ELISA para detecção de anticorpos para o vírus do sarampo: comparação com reações de inibição da hema-glutinação, imunofluorescência indireta e neutralização de placas

    Directory of Open Access Journals (Sweden)

    Vanda Akico Ueda Fick de Souza

    1991-02-01

    Full Text Available An enzyme-linked immunosorbent assay (ELISA for measles antibodies was compared with Plaque Neutralization (PRN, Haemagglutination inhibition (HI and Fluorescent antibody (IFA tests in 181 sera from vaccinated children and umbilical cord. Of 179 positive samples by the sensitive PRN, only two, with titers of 8, were negative by ELISA (copositivity of 98.9%. IFA and HI presented, respectively, copo-sitivities of 93.3% and 82.7%. The ELISA presented a high sensitivity as well as a good reproducibility and represents an alternative for the time consuming PRN for detection of low measles antibodies.A reação imunoenzimática (ELISA para determinação de anticorpos para o vírus do sarampo foi comparada com a reação de neutralização de placas (RNP, inibição da hemaglutinação (RIH e imunofluorescência indireta (RIF. Das 179 amostras positivas pela RNP, somente 2, com títulos iguais a 8, se apresentaram negativas por ELISA (copositividade de 98.9%. A RIF e RIH apresentaram, respectivamente, copositividade de 93.3 e 82.7%. ELISA apresentou sensibilidade equivalente à complexa RNP, boa reprodutibilidade e representa uma alternativa para a detecção de baixos títulos de anticorpos contra o sarampo.

  20. Prueba de Elisa indirecta para la detección de anticuerpos IgM para el diagnóstico de Leptospirosis humana

    Directory of Open Access Journals (Sweden)

    Manuel Céspedes Z

    2002-01-01

    Full Text Available Para el diagnóstico temprano de enfermedades con cuadro clínico inespecífico como la leptospirosis, es necesario la confirmación laboratorial mediante pruebas específicas, con la finalidad de que el diagnóstico sea más acertado y rápido. Objetivo: se realizó un estudio comparativo entre la prueba de microaglutinacion (MAT y la prueba de ELISA indirecta estandarizada con un "pool" de antígenos de Leptospira interrogans, para la detección de anticuerpos IgM, en muestras de suero de fase aguda de leptospirosis humana. Materiales y métodos: 40 muestras de pacientes con sospecha clínica y con títulos de 1:100-1:12800 por la prueba de MAT, 80 muestras negativas de pacientes aparentemente sanos con enfermedades como Brucelosis, Sífilis, Tifus murino, Hepatitis B, Fiebre Amarilla, Dengue y Enfermedad de Carrión fueron evaluados por ELISA IgM. Resultados: se obtuvo una sensibilidad de 97,5% y especificidad de 98,75%, no observándose reacción cruzada con otras enfermedades. Conclusión: ELISA IgM validado en el laboratorio es suficiente sensible, específico y de fácil aplicación para el uso como prueba de tamizaje en una infección por Leptospiras con la subsecuente confirmación por MAT.

  1. [A double antibody sandwich ELISA based assay for titration of severe fever with thrombocytopenia syndrome virus].

    Science.gov (United States)

    Liu, Lin; Zhang, Quan-Fu; Li, Chuan; Li, Jian-Dong; Jiang, Xiao-Lin; Zhang, Fu-Shun; Wu, Wei; Liang, Mi-Fang; Li, De-Xin

    2013-06-01

    To develop an assay for titration of severe fever with thrombocytopenia syndrome virus (SFTSV) based on double antibody sandwich ELISA. A double antibody sandwich ELISA was developed for detection of SFTSV based on SFTSV nucleocapsid (N) protein specific poly- and monoclonal antibodies, procedures were optimized and evaluated. This ELISA based titration assay was compared with fluorescence assasy and plaque assay based titration method. The results suggested that the titers obtained by ELISA based method are consistent with those obtained by IFA based method (R = 0.999) and the plaque assay titration method (R = 0.949). The novel ELISA based titration method with high sensitivity and specificity is easy to manage and perform, and can overcome the subjectivity associated with result determination of the fluorescence assay and plaque assay based methods. The novel ELISA based titration method can also be applied to high throughput detection.

  2. Evaluation of an indirect ELISA for detection and typing of foot-and-mouth disease virus

    International Nuclear Information System (INIS)

    Prado, J.A.

    1998-01-01

    An indirect enzyme linked immunosorbent assay (ELISA) kit was used for diagnosis of foot-and-mouth disease virus (FMDV) types O1, A23, C3 which occurred in Rio Grande do Sul State, Southern Brazil during 1984-1994. The samples were randomly selected and tested by ELISA, Complement Fixation Test (CFT) and in tissue culture. Out of 106 samples 78 (73,5%) were positive by ELISA and 39 (36,8%) were found positive in CFT, when original suspensions were used. Once these samples were inoculated onto tissue culture both tests gave similar results, although ELISA picked up more positive samples during the 1st passage in tissue culture. The negative samples (16) included in this study were negative in all tests. The ELISA was more sensitive than and as specific as CFT. ELISA and tissue culture together were shown to be a better system for detection of foot-and-mouth disease virus antigen than CFT. (author)

  3. Fasciola hepatica saposin-like-2 protein based ELISA for the serodiagnosis of chronic human fascioliasis

    Science.gov (United States)

    Figueroa-Santiago, Olgary; Delgado, Bonnibel; Espino, Ana M.

    2011-01-01

    An indirect enzyme-linked immunosorbent assay (ELISA) was developed and evaluated for its diagnostic ability to detect human IgG antibodies against Fasciola hepatica saposin-like protein-2. The assay was compared with an indirect ELISA with excretory-secretory products (FhES) from adult F. hepatica. In an analysis of the sera of 37 patients infected with F. hepatica, 40 patients with other parasitic infections, and 50 healthy controls, the sensitivity of both ELISA assays was 100%. However, the FhSAP2-based ELISA was more specific (95.6%) than the FhES-ELISA (91.9%). These results demonstrated that FhSAP2 can be used in the serodiagnosis of chronic human fascioliasis with additional advantage that is relative cheap and easy to produce. Studies are in progress to evaluate this FhSAP2-ELISA assay in a large-scale prevalence surveys in endemic areas. PMID:21683266

  4. The evaluation of CLIA, RIA and MSP-ELISA for measurement of thyroid hormones

    International Nuclear Information System (INIS)

    Jing Hua; Li Dan; Chen Yiguang; Zhou Huiqin; Xu Liyan

    2005-01-01

    To compare the characteristics of chemiluminescent immunoassay (CLIA), RIA and magnetic solid phase enzyme-linked immnosorbent assay (MSP-ELISA) in measuring thyroid hormones, TT 3 , TT 4 , FT 3 , FT 4 and TSH were tested in 40 samples of human serum and in standard samples of thyroid hormones by CLIA, RIA and MSP-ELISA respectively. The linearity, relativiy, precision, recovery of these three met hods were compared. The result showed that there were no statistical differences between CLIA, RIA and MSP-ELISA in linearity and relativity. CLIA was better than RIA and MSP-ELISA in precision and accuracy. (authors)

  5. A multi-purpose ultrasonic streaming mixer for integrated magnetic bead ELISAs

    International Nuclear Information System (INIS)

    Brandhoff, Lukas; Lang, Walter; Vellekoop, Michael J; Zirath, Helene; Peham, Johannes; Wiesinger-Mayr, Herbert; Salas, Mariugenia; Haller, Anna; Spittler, Andreas; Schnetz, Guntram

    2015-01-01

    We present an ultrasonic streaming mixer for disposable and on-chip magnetic bead ELISAs. The ultrasonic transducer is placed at system-level to keep cost per chip as low as possible, and is coupled to the chip by means of a solid ultrasonic horn. The system provides mixing of liquids, as well as dispersion of the superparamagnetic beads in the ELISA. Additionally it can be used clean the chamber surface from nonspecifically bound proteins during the washing steps in the ELISA protocol. Using our system the time for the ELISA protocol has been greatly reduced down to 30 min. (paper)

  6. Prospects of eLISA for Detecting Galactic Binary Black Holes Similar to GW150914

    OpenAIRE

    Seto, Naoki

    2016-01-01

    We discuss the prospects of eLISA for detecting gravitational waves (GWs) from Galactic binary black holes (BBHs) similar to GW150914. For a comoving merger rate that is consistent with current observation, eLISA is likely to identify at least one BBH with a sufficient signal-to-noise ratio. In addition, eLISA has a potential to measure the eccentricity of the BBH as small as $e\\sim 0.02$, corresponding to the residual value $e\\sim 10^{-6}$ at 10Hz. Therefore, eLISA could provide us with a cr...

  7. Application of anti-leptospira ELISA-lgM for the etiologic elucidation of meningitis Aplicação do ELISA-IgM anti-leptospira na elucidação etiológica das meningites

    Directory of Open Access Journals (Sweden)

    Marcos V Silva

    1996-04-01

    Full Text Available Leptospirosis is one of the causes of meningitis, although its importance is not well known. In the present study we contributed to this knowledge by demonstrating specific IgM class anti-leptospira antibodies by the immunoenzymatic method ELISA in 14.6% of cerebrospinal fluid (CSF samples from 171 patients with meningitis considered to be of indeterminate etiology. The frequencies of positivity were similar in cases with predominance of polymorphonuclear or lymphomononuclear leucocytes in the CSF. Age distribution showed a predominance of the 5 to 15 year age range (72%, and sex distribution showed a predominance of males (68%. The authors discuss the contribution of this method to the etiologic elucidation of meningitis.A Leptospirose é uma das causas de meningite, embora sua importância seja pouco conhecida. O presente estudo contribui para este conhecimento ao demonstrar anticorpos específicos da classe IgM anti-Leptospira pelo método imunoenzimático (ELISA, em 14,6% das amostras de líqüido cefalorraquianos (LCR de 171 pacientes com meningite considerada de etiología indeterminada. As freqüências de positividade foram parecidas nos casos com predomínio no LCR de leucócitos polimorfonucleares ou linfomononucleares. A distribuição por idade mostrou predomínio na faixa etária entre 5 e 15 anos (72% e por sexo o predomínio do masculino (68%. Os autores discutem a contribuição desse método na elucidação etiológica das meningites.

  8. UltramicroELISA para la detección de anticuerpos IgM anti M. leprae UltramicroELISA assay for the detection of human IgM antibodies to M. leprae

    Directory of Open Access Journals (Sweden)

    José Laferte

    1991-12-01

    Full Text Available La disponibilidad del sistema Ultramicroanalítico (SUMA y de un antígeno especie-específico del M. leprae obtenido mediante síntesis química, permitió la normalización y validación de un ultramicroELISA para la detección de anticuerpos IgM específicos a esta micobacteria. El análisis de 433 sueros de banco de sangre y 265 sueros usados para validar el método y clasificados en un grupo control de donantes de banco de sangre (100, un grupo de pacientes tuberculosos (50, un grupo de enfermos de lepra (65 y un grupo de contactos de estos enfermos (50, mostró la especificidad del ensayo para evidenciar la infección con el M. leprae. Los resultados obtenidos del estudio adicional de 140 muestras de suero de contactos de enfermos estuvieron estrechamente correlacionados (r = 0,98 con los resultados obtenidos por la técnica de microELISA convencional. La utilización del SUMA no solo permite un notable ahorro de reactivos si no además facilita la lectura, cálculo, validación y almacenamiento automático de los resultados.The availability of an ultramicroanalitic system (SUMA and specie-specific antigen of M. leprae obtained by chemical synthesis, have made possible the standardization and validation of an ultramicroELISA assay for detecting specific human IgM antibodies to this mycobacterium. The specificity of this test to demonstrate the infection with M. leprae was corroborated through a screening of 433 blood bank serum samples and other 265 from diferent groups (100, control group, 50 tuberculosis patients, 65 leprosy patients, 50 from household. The results obtained in the aditional study of 140 household sero showed a high correlation (r = 0.98 with the conventional microELISA method. The use of SUMA allows saving reagents and time since sample handling, plate reading, print out and storing the data are computer assisted.

  9. ELISA analysis of soybean trypsin inhibitors in processed foods.

    Science.gov (United States)

    Brandon, D L; Bates, A H; Friedman, M

    1991-01-01

    Soybean proteins are widely used in human foods in a variety of forms, including infant formulas, flour, protein concentrates, protein isolates, soy sauces, textured soy fibers, and tofu. The presence of inhibitors of digestive enzymes in soy proteins impairs the nutritional quality and possibly the safety of soybeans and other legumes. Processing, based on the use of heat or fractionation of protein isolates, does not completely inactivate or remove these inhibitors, so that residual amounts of inhibitors are consumed by animals and humans. New monoclonal antibody-based immunoassays can measure low levels of the soybean Kunitz trypsin inhibitor (KTI) and the Bowman-Birk trypsin and chymotrypsin inhibitor (BBI) and the Bowman-Birk foods. The enzyme-linked immunosorbent assay (ELISA) was used to measure the inhibitor content of soy concentrates, isolates, and flours, both heated and unheated; a commercial soy infant formula; KTI and BBI with rearranged disulfide bonds; browning products derived from heat-treatment of KTI with glucose and starch; and KTI exposed to high pH. The results indicate that even low inhibitor isolates contain significant amounts of specific inhibitors. Thus, infants on soy formula consume about 10 mg of KTI plus BBI per day. The immunoassays complement the established enzymatic assays of trypsin and chymotrypsin inhibitors, and have advantages in (a) measuring low levels of inhibitors in processed foods; and (b) differentiating between the Kunitz and Bowman-Birk inhibitors. The significance of our findings for food safety are discussed.

  10. Electrocardiografo por computadora

    OpenAIRE

    Tinoco Hernandez, Rosanna; Paredes Bejarano, Margarita; Romero Chaglia, Norman; Yapur Auad, Miguel Eduardo

    2009-01-01

    El presente trabajo trata sobrees el diseño y la implementación de un graficador de señales cardiacas por computadora, para lo cual diseñamos un circuito electrónico capaz de recibir la senal analógica proveniente de la actividad electrica del corazón , amplificarla, y luego convertirla en una señal digital para ser procesada por software y finalmente ser graficada, siendo posible así observar la señal cardiaca en el monitor de un computador como un tren de pulsos. Cabe destacar que par...

  11. TOXOCARIASIS: SEROLOGICAL DIAGNOSIS BY INDIRECT ANTIBODY COMPETITION ELISA Diagnóstico sorológico da toxocaríase através do método de ELISA indireto de competição

    Directory of Open Access Journals (Sweden)

    Cáris Maroni NUNES

    1999-03-01

    Full Text Available Toxocariasis is caused by infection of man by Toxocara canis and Toxocara cati larvae, the common roundworm of dogs and cats. Because larvae are difficult to detect in tissues, diagnosis is mostly based on serology. Non specific reactions are observed mainly due to cross-reactivity with Ascaris sp antigens. This investigation aimed at developing and evaluating an indirect antibody competition ELISA (IACE employing a specific rabbit IgG anti-Toxocara canis excretory-secretory antigens as the competition antibody, in order to improve indirect ELISA specificity performed for toxocariasis diagnosis. For that, the rabbit IgG was previously absorbed by Ascaris suum adult antigens. Sensitivity and specificity of IACE were first evaluated in 28 serum samples of mice experimentally infected with T. canis embryonated eggs. Adopting cut-off value established in this population before infection, sensitivity and specificity were 100% after 20 days post-inoculation. For human population IACE was evaluated using sera from 440 patients with clinical signs of toxocariasis and the cut-off value was established with 60 serum samples from apparently healthy individuals. Using as reference test the indirect ELISA performed by Adolfo Lutz Institute, sensitivity was 60.2%, specificity was 98% and concordance was 77.3%. Repeatability of IACE was evaluated by the inter-reactions variation coefficient (2.4%.A toxocaríase, uma emergente zoonose, é uma síndrome clínica decorrente da infecção humana por larvas de Toxocara canis e Toxocara cati, parasitas intestinais de cães e gatos, respectivamente. A dificuldade de detecção das larvas nos tecidos e a inespecificidade dos sinais clínicos tornam os testes sorológicos os meios diagnósticos mais adequados. Os antígenos excretores-secretores de T. canis empregados nos testes sorológicos, embora tenham contribuído para melhorar a especificidade destes, apresentam reações cruzadas com diversos parasitas

  12. Teste de ELISA indireto para diagnóstico sorológico de leishmaniose visceral em canídeos silvestres Indirect ELISA for the serological diagnosis of visceral leishmaniasis in wild canids

    Directory of Open Access Journals (Sweden)

    Paulo R.B. Ferreira

    2013-04-01

    Full Text Available Na América do Sul, alguns canídeos silvestres são considerados reservatórios naturais da Leishmania chagasi. A resposta imunológica desses animais à Leishmania é pouco conhecida, havendo a necessidade de métodos diagnósticos adequados para esse fim. No presente estudo, é descrita a padronização do ensaio imunoenzimático indireto (ELISA para o diagnóstico sorológico de leishmaniose visceral em canídeos silvestres brasileiros. Foram estudadas amostras de soro e plasma de 12 canídeos cativos: sete lobos-guará (Chrysocyon brachyurus, três raposinhas (Lycalopex vetulus e dois cachorros-do-mato (Cerdocyon thous. As amostras de um C. brachyurus e uma L. vetulus, cativos em área endêmica para LV, que apresentavam doença clínica e positividade em testes de Imunofluorescência Indireta e Reação em Cadeia de Polimerase, foram utilizadas como controles positivos. Foram comparados os conjugados anti-IgG de cão e proteína A, ambos ligados a peroxidase, cujos testes detectaram quatro (04/12 e três (03/12 C. brachyurus soropositivos para anticorpos anti-Leishmania sp., respectivamente. As médias das densidades ópticas (DOs das amostras negativas foram nitidamente mais baixas do que as médias das DOs dos positivos tanto no ELISA com anti-IgG de cão (4,8 vezes como com proteína A (15,5 vezes. Os soros de três C. brachyurus positivos no ELISA indireto foram avaliados por Western blotting e identificaram 22 bandas, sendo imunodominantes as de peso molecular de 19, 22, 24, 45 e 66 kDa. Os testes ELISA com a proteína A e o conjugado anti-IgG de cão apresentaram respectivamente concordância excelente (Kappa = 1; pIn South America, some wild canids are considered natural reservoirs of Leishmania chagasi. The immunological response of wild canids to Leishmania is not well understood, and the development of diagnostic methods is necessary for such purpose. In the present study, the standardization of an enzyme-linked immunosorbent

  13. Undergraduate Laboratory Module for Implementing ELISA on the High Performance Microfluidic Platform

    Science.gov (United States)

    Giri, Basant; Peesara, Ravichander R.; Yanagisawa, Naoki; Dutta, Debashis

    2015-01-01

    Implementing enzyme-linked immunosorbent assays (ELISA) in microchannels offers several advantages over its traditional microtiter plate-based format, including a reduced sample volume requirement, shorter incubation period, and greater sensitivity. Moreover, microfluidic ELISA platforms are inexpensive to fabricate and allow integration of…

  14. A sandwich ELISA for measurement of the primary glucagon-like peptide-1 metabolite

    DEFF Research Database (Denmark)

    Wewer Albrechtsen, Nicolai J; Asmar, Ali; Jensen, Frederik

    2017-01-01

    developed a sandwich ELISA recognizing both GLP-1 9-36NH2 and nonamidated GLP-1 9-37. The ELISA was validated using analytical assay validation guidelines and by comparing it to a subtraction-based method, hitherto employed for estimation of GLP-1 9-36NH2 Its accuracy was evaluated from measurements...

  15. Elisa ja EMT kemplevad, kumb pakub paremat levi / Toivo Tänavsuu

    Index Scriptorium Estoniae

    Tänavsuu, Toivo

    2007-01-01

    Mobiilifirma Elisa väitel on Tartus kõige kvaliteetsem leviala Elisal. EMT võrgujuhi Margus Malvi hinnangul on EMT ja Elisa võrgud Tartus samaväärsed, ainus erinevus on kliendi kaugus tugijaamast. Lisa: Mobiililevi kvaliteet

  16. Early antihepatitis C virus response with second-generation C200/C22 ELISA

    NARCIS (Netherlands)

    van der Poel, C. L.; Bresters, D.; Reesink, H. W.; Plaisier, A. A.; Schaasberg, W.; Leentvaar-Kuypers, A.; Choo, Q. L.; Quan, S.; Polito, A.; Houghton, M.

    1992-01-01

    Detection of early antibody to hepatitis C virus (HCV) by a new second-generation C200/C22 anti-HCV enzyme-linked immunosorbent assay (ELISA) and a four-antigen recombinant immunoblot assay (4-RIBA) was compared with the first-generation anti-HCV C100 ELISA using sequential serum samples of 9

  17. EMT nurjas Rate.ee ostuga Elisa kõnekaardiplaani / Gert D. Hankewitz

    Index Scriptorium Estoniae

    Hankewitz, Gert D.

    2006-01-01

    Ilmunud ka: Delovõje Vedomosti 12. apr. lk. 2. Elisa juhatuse esimehe Sami Seppäneni sõnul ostis EMT suhtlusportaali Rate.ee, kuna sai teada, et Elisa ning portaal plaanivad koos uue kõnekaardi turule tuua

  18. Development of a sandwich ELISA for quantification of immunoglobulin G in mink blood

    DEFF Research Database (Denmark)

    Mathiesen, Ronja; Chriél, Mariann; Struve, T.

    2016-01-01

    early immunity and thus their resistance against pathogenic agents found in the environment. This study describes a sandwich ELISA for quantification of the concentration of total immunoglobulin G in mink blood. The ELISA was validated with serum samples from females (n=8) and their kits (litters of 4...

  19. ANALYSIS OF SOIL AND DUST SAMPLES FOR POLYCHLORINATED BIPHENYLS BY ENZYME LINKED IMMUNOSORBENT ASSAY (ELISA)

    Science.gov (United States)

    An inhibition enzyme-linked immunosorbent assay (ELISA) was used to determine polychlorinated biphenyls (PCBs) in house dust and soil. Soil and house dust samples were analyzed for PCB by both gas chromatography/electron capture detection (GC/ECD) and ELISA methods. A correlati...

  20. Indice por Materias

    Directory of Open Access Journals (Sweden)

    Montoya H Luz Marina

    1982-09-01

    Full Text Available Un índice es una lista de palabras o frases indicadores asociados que permite la ubicación de material al interior de un libro o una publicación, en este caso será por el nombre de la materia.

  1. Evaluation of CSFV Antibody ELISAs for the differentiation of infected from vacci-nated animals

    DEFF Research Database (Denmark)

    Schroeder, Sabine; Blome, Sandra; Koenen, Frank

    countries and out-breaks occurred recently e.g. in Germany, France, Hungary, Romania, Bulgaria, and the Slovak Republic. Preventive vaccination is prohibited within the EU, but emergency vaccination can be part of the strategy in case of a contingency. Using conventional vaccines, differentiation...... of vaccinated from infected animals (DIVA) is not possible. Newly developed modified live marker vaccines allow a DIVA strategy based on the use of enzyme linked immunosorbent assay (ELISA) tests. The aim of this study was to evaluate CSF virus (CSFV) Antibody ELISAs, com-mercially available in Europe......, for their diagnostic sensitivity as well as for their potential in differentiating between infected and marker vaccinated animals. Two newly available ELISAs were included into the tests, the Priocheck® CSFV Erns ELISA, a special DIVA test, and the LDL Pigtype® CSFV Antibody ELISA. An inter-laboratory comparison test...

  2. Cystatin capture elisa immunodiagnosis of human fasciolosis at Chupaca-Junin Province

    International Nuclear Information System (INIS)

    Cornejo, W.; Alva, P.; Sevilla, C.; Huiza, A.; Universidad Nacional Mayor de San Marcos, Lima

    2003-01-01

    To determine the prevalence of human fasciolosis in an endemic area by means of an Enzyme-Linked Immunosorbent Assay (ELISA) using cystatin as a capture agent for the detection of specific antibodies to fasciola hepatica cysteine proteinases. An ELISA plate was sensitized with cystatin, incubated with excretory-secretory products of adult flukes, and followed by standard ELISA procedures. Clinical applicability of the cystatin capture ELISA for the immunodiagnosis of fasciolosis was tested with 200 serum samples of children and adults from an endemic area in Chupaca province, Junin department. Serum samples from the endemic area tested by cystatin capture ELISA showed 27/200 (13,5%) of positive cases. Fasciolosis remains a major health problem at Chupaca province, Junin department

  3. Introducción de un ELISA como ensayo alternativo en la determinación de la potencia de vacunas antitetánicas

    Directory of Open Access Journals (Sweden)

    Juan Carlos Ramírez

    2005-05-01

    Full Text Available Por más de medio siglo de uso, la vacunación con el toxoide tetánico ha mostrado un elevado porcentaje de eficacia en la prevención del tétanos. Este trabajo pretende introducir un ensayo inmunoenzimático en fase sólida (ELISA como método alternativo a la prueba de seroneutralización in vivo utilizada en la evaluación de la potencia de las vacunas antitetánicas.Se desarrolló un ELISA de tipo indirecto para la cuantificación de antitoxina tetánica en suero de curiel a partir de un estándar con 29 UI/mL, previamente calibrado. Se determinó la precisión, exactitud y linealidad del ensayo. Se analizó la correlación entre el ELISA y la prueba biológica mediante la evaluación de un total de 75 muestras de sueros por ambos métodos. Por último, se estudió la respuesta individual de un grupo de animales contra 15 lotes de toxoide tetánico. El ensayo demostró ser preciso y exacto, con imprecisiones inferiores al 20% y valores de recuperación entre el 90–110%. Las desviaciones del paralelismo mostraron coeficientes de variación alrededor del 10%. El análisis por regresión lineal mostró una buena correlación entre el ELISA y el ensayo biológico (R2= 0,989. El método alternativo desarrollado probó ser una herramienta útil para la determinación de la potencia de vacunas antitetánicas a partir de la evaluación independiente de la respuesta de cada animal contra el toxoide tetánico.Los niveles de seroprotección alcanzados se encontraron entre el 83–100%.

  4. Apendicitis por Paracoccidioides brasiliensis

    Directory of Open Access Journals (Sweden)

    Ana Beatriz MUÑOZ URRIBARRI

    2006-01-01

    Full Text Available La paracoccidioidomicosis es la micosis más prevalente en Sudamérica. La forma aguda afecta el sistema fagocítico mononuclear de niños y personas inmunocomprometidas. El compromiso gastrointestinal es frecuente y su patogenia implica diseminación hematógena y linfática. La linfadenomegalia abdominal causa obstrucción intestinal y abdomen agudo. En este artículo damos a conocer el caso de un niño con compromiso gastrointestinal por apendicitis. Este es el primer caso reportado de apendicitis por esta patología. (Rev Med Hered 2006;17:58-60.

  5. A Simple and Specific Noncompetitive ELISA Method for HT-2 Toxin Detection

    Directory of Open Access Journals (Sweden)

    Henri O. Arola

    2017-04-01

    Full Text Available We developed an HT-2 toxin-specific simple ELISA format with a positive read-out. The assay is based on an anti-immune complex (IC scFv antibody fragment, which is genetically fused with alkaline phosphatase (AP. The anti-IC antibody specifically recognizes the IC between a primary anti-HT-2 toxin Fab fragment and an HT-2 toxin molecule. In the IC ELISA format, the sample is added together with the scFv-AP antibody to the ELISA plate coated with the primary antibody. After 15 min of incubation and a washing step, the ELISA response is read. A competitive ELISA including only the primary antibody recognizes both HT-2 and T-2 toxins. The anti-IC antibody makes the assay specific for HT-2 toxin, and the IC ELISA is over 10 times more sensitive compared to the competitive assay. Three different naturally contaminated matrices: wheat, barley and oats, were used to evaluate the assay performance with real samples. The corresponding limits of detection were 0.3 ng/mL (13 µg/kg, 0.1 ng/mL (4 µg/kg and 0.3 ng/mL (16 µg/kg, respectively. The IC ELISA can be used for screening HT-2 toxin specifically and in relevant concentration ranges from all three tested grain matrices.

  6. Detection of Fusarium verticillioides by PCR-ELISA based on FUM21 gene.

    Science.gov (United States)

    Omori, Aline Myuki; Ono, Elisabete Yurie Sataque; Bordini, Jaqueline Gozzi; Hirozawa, Melissa Tiemi; Fungaro, Maria Helena Pelegrinelli; Ono, Mario Augusto

    2018-08-01

    Fusarium verticillioides is a primary corn pathogen and fumonisin producer which is associated with toxic effects in humans and animals. The traditional methods for detection of fungal contamination based on morphological characteristics are time-consuming and show low sensitivity and specificity. Therefore, the objective of this study was to develop a PCR-ELISA based on the FUM21 gene for F. verticillioides detection. The DNA of the F. verticillioides, Fusarium sp., Aspergillus sp. and Penicillium sp. isolates was analyzed by conventional PCR and PCR-ELISA to determine the specificity. The PCR-ELISA was specific to F. verticillioides isolates, showed a 2.5 pg detection limit and was 100-fold more sensitive than conventional PCR. In corn samples inoculated with F. verticillioides conidia, the detection limit of the PCR-ELISA was 1 × 10 4 conidia/g and was also 100-fold more sensitive than conventional PCR. Naturally contaminated corn samples were analyzed by PCR-ELISA based on the FUM21 gene and PCR-ELISA absorbance values correlated positively (p PCR-ELISA developed in this study can be useful for F. verticillioides detection in corn samples. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Purification of a polyclonal antibody against CD147 for ELISA using antigen-immunoaffinity chromatography

    Science.gov (United States)

    Liu, Shuangshuang; Li, Shasha; Zhang, Yang; Wang, Ye; Zhu, Yumeng; Wang, Bin; Chen, Zhi-Nan

    2017-01-01

    The immunoglobulin superfamily member CD147 is a widely expressed glycoprotein that occurs in both a membrane-spanning and soluble form. Sandwich ELISA is a powerful tool for analyzing soluble antigens. The aim of the present study was to obtain a highly specific polyclonal antibody against human CD147 that can be used for sandwich ELISA analysis. Expression of recombinant CD147 by a eukaryotic expression system was used to immunize rabbits to obtain antiserum. A highly specific polyclonal antibody that was able to detect soluble CD147 in sandwich ELISA was obtained by antigen-immunoaffinity chromatography purification. The purity of rabbit anti-CD147 polyclonal antibodies was ~99%, and ELISA analysis was able to determine the titer of the rabbit anti-CD147 polyclonal antibodies at 1:512,000. The lowest concentration of the standard CD147 antigen that the sandwich ELISA was able to detect was 31.25 pg/ml. The sandwich ELISA system was composed of anti-hepatoma HAb18 monoclonal antibodies and purified rabbit anti-CD147 polyclonal antibodies. The present study demonstrated that antigen-immunoaffinity chromatography may be a good technique for the purification of polyclonal antibodies, which may be used to detect antigen in sandwich ELISAs. PMID:28487989

  8. Homologous ELISA for detection of oligomeric human TNF: properties of the assay.

    Science.gov (United States)

    Petyovka, N; Lyach, L; Voitenok, N N

    1995-10-26

    In order to quantify oligomeric human tumor necrosis factor-alpha (TNF), we have developed a sensitive homologous enzyme-linked immunosorbent assay (Hm-ELISA) using the same monoclonal antibody (MoAb) for both solid and liquid phase. Different anti-TNF MoAb have been compared in terms of their efficacy in the Hm-ELISA, affinity, neutralization capacity and epitope specificity. The data suggest, that effectiveness in the Hm-ELISA may represent a novel characteristic of MoAb. Of the MoAbs tested, 5 N was capable of recognizing oligomeric TNF in the Hm-ELISA with a detection limit of 15 pg/ml. Furthermore, using Hm-ELISA against human TNF, interleukin-8 (IL-8) and lymphotoxin, we have demonstrated that these cytokines are oligomeric in physiological solutions, but are converted into monomeric forms in the presence of the non-ionic detergent Tween 20. High salt buffer was employed to abrogate a nonspecific false positive reaction in the Hm-ELISA found in nearly half of the plasma samples obtained from healthy subjects. Finally, a good correlation between the Hm-ELISA and the L929 bioassay was observed for natural and recombinant TNF measured in human plasma.

  9. Evaluation of serum and milk ELISAs for paratuberculosis in Danish dairy cattle

    DEFF Research Database (Denmark)

    Klausen, Joan; Huda, A.; Ekeroth, Lars

    2003-01-01

    concurrently from six dairy herds infected with MAP and from two dairy herds without history of infection with MAP. A cut-off value of 7 OD% was used in the ELISAs. At this cut-off value, all six culture-positive herds were positive in the serum ELISA but one was negative in the milk ELISA. All six culture......-positive herds were positive in the CFT. In the two culture-negative herds, the serum and the milk ELISA deemed all serum samples negative at this cut-off value, whereas four serum samples from one of these herds were positive in the CFT. The highest cut-off value enabling the milk ELISA to record all six...... culture-positive herds as positive was 4 OD%. The highest cut-off value enabling the serum ELISA to record all six culture-positive herds as positive was 17 OD%. Individual-sample relative sensitivities of the ELISAs ranged from 49 to 64% and relative specificities were 80-96% at the cut-off values of 4...

  10. [Use of new immunoglobulin isotype-specific ELISA-systems to detect Salmonella infections in pigs].

    Science.gov (United States)

    Ehlers, Joachim; Alt, Michael; Trepnau, Daniela; Lehmann, Jörg

    2006-01-01

    In Germany, the program for controlling salmonella infections in pigs is based on tests detecting salmonella-lipopolysaccharide (LPS) induced antibodies in meat-juice or blood. These conventional tests which are based on the technology of enzyme-linked immunosorbent assay (ELISA) detect exclusively or mainly immunoglobulin(lg)G antibodies. Meanwhile, novel ELISA systems (WCE-ELISA, 3-Isotype-Screening-ELISA) have been developed, which additionally detect the antibody classes IgM and IgA.This fact enables the registration of fresh salmonella infections (starting with day 5 p.i.) and thus, the distinction between early and older infections. The results show that animals with early salmonella infections appear significantly more often in herds with a high than with a low prevalence. With the newly developed tests this group of animals can be detected much more efficiently and precisely than with the tests used so far. Due to their clearly improved sensitivity the application of the WCE-ELISA and the 3-Isotype-Screening-ELISA in terms of the QS-Salmonella-Monitoring program can therefore significantly improve the selection of farms with potential salmonella excretors. Additionally, the WCE-ELISA can be applied very suitable for the examination of individual animals.

  11. Microchip ELISA coupled with cell phone to detect ovarian cancer HE4 biomarker in urine.

    Science.gov (United States)

    Wang, ShuQi; Akbas, Ragip; Demirci, Utkan

    2015-01-01

    Ovarian cancer is a leading cause of death from gynecologic cancers in the USA, and early diagnosis can potentially increase 5-year survival rate. Detection of biomarkers derived from hyperplasia of epithelial tissue by enzyme-linked immunosorbent assay (ELISA) proves to be a practical way of early diagnosis of ovarian cancer. However, ELISA is commonly performed in a laboratory setting, and it cannot be used in a clinical setting for on-site consultation. We have shown a microchip ELISA that detects HE4, an ovarian cancer biomarker, from urine using a cell phone integrated with a mobile application for imaging and data analysis. In microchip ELISA, HE4 from urine was first absorbed on the surface; the primary and secondary antibodies were subsequently anchored on the surface via immuno-reaction; and addition of substrate led to color development because of enzymatic labeling. The microchip after color development was imaged using a cell phone, and the color intensity was analyzed by an integrated mobile application. By comparing with an ELISA standard curve, the concentration of HE4 was reported on the cell phone screen. The presented microchip ELISA coupled with a cell phone is portable as opposed to traditional ELISA, and this method can facilitate the detection of ovarian cancer at the point-of-care (POC).

  12. EVALUATION OF AN O-ANTIGEN ELISA FOR SCREENING CATTLE HERDS FOR SALMONELLA-TYPHIMURIUM

    DEFF Research Database (Denmark)

    Hoorfar, Jeffrey; Bitsch, V.

    1995-01-01

    A total of 2585 serum samples from 62 dairy herds located in four different regions of Denmark were tested in an O-antigen (0:1,4,5,12)-based ELISA for the detection of antibodies against Salmonella typhimurium. Ten closed herds from an island with no reported occurrence of salmonellosis for seve......A total of 2585 serum samples from 62 dairy herds located in four different regions of Denmark were tested in an O-antigen (0:1,4,5,12)-based ELISA for the detection of antibodies against Salmonella typhimurium. Ten closed herds from an island with no reported occurrence of salmonellosis...... for several years, and 12 herds from a salmonella enzootic area which had had clinical outbreaks of S typhimurium were used to define a herd ELISA cut-off value. When herds with at least 5 per cent of the serum samples having an optical density of >0.5 were considered ELISA-positive, all 10 herds from...... the salmonellosis-free island were ELISA-negative, and all but one of the 12 S typhimurium-infected herds were ELISA-positive, which resulted in a herd test sensitivity of 0.92 and herd test specificity of 1.0. Eleven of the 12 S typhimurium-infected herds were negative in a blocking ELISA based on a monoclonal...

  13. RT-PCR-ELISA as a tool for diagnosis of low-pathogenicity avian influenza

    DEFF Research Database (Denmark)

    Dybkaer, Karen; Munch, Mette; Handberg, Kurt Jensen

    2003-01-01

    A one-tube reverse transcriptase/polymerase chain reaction coupled with an enzyme-linked immunosorbent assay (RT-PCR-ELISA) was developed for the rapid detection of avian influenza virus (AIV) in clinical specimens. A total of 419 swab pools were analyzed from chickens experimentally infected wit...... of the twenty-three VI-positive specimens were negative when tested by RT-PCR-ELISA. The diagnostic sensitivity and specificity of the RT-PCR-ELISA was 91% and 97%, respectively, using VI in SPF eggs as the gold reference standard....

  14. Use of a trypanosomal antigen ELISA to monitor tsetse and trypanosomosis control programmes in Kenya

    Energy Technology Data Exchange (ETDEWEB)

    Olaho-Mukani, W; Munga, L K; Nyanga` O, J N.M.; Ouma, J O; Masika, P; Okech, G; Ndungu, J M [Kenya Trypanosomiasis Research Inst., Kikuyu (Kenya)

    1997-02-01

    The capture Antigen-ELISA was used to monitor serum samples originating from three study areas in Kenya. At the Galana ranch the test was used to assess re-invasion of an area previously cleared of Glossina pallidipes. In Busia district the Ag-ELISA is being used to monitor the progress of a tsetse and trypanosomosis control programme. At Taita and Tara ranches the capture Antigen ELISA and the buffy coat technique (BCT) were used to evaluate the efficacy of a commercial Cypermethrin dip for the control of Glossina pallidipes. (author). 3 refs, 4 figs, 2 tabs.

  15. Development and evaluation of an ELISA for human trefoil factor 3

    DEFF Research Database (Denmark)

    Vestergaard, Else Marie; Poulsen, Steen Seier; Grønbaek, Henning

    2002-01-01

    are warranted. METHODS: An ELISA was developed that uses two antibodies from rabbits immunized with recombinant human TFF3 and a calibrator (3-100 pmol/L) prepared from recombinant human TFF3. RESULTS: The ELISA had a detection limit of 3.0 pmol/L. The imprecision (CV) was 5-9% for mean concentrations of 13...... exacerbation of chronic inflammatory bowel disease restricted to the colon, normal concentrations and only minor variations during treatment and tapering were observed. CONCLUSIONS: The ELISA measures TFF3 in human serum and represents a specific and precise method for measurement of TFF3, which...

  16. DETECTION OF SERIAL SERUM P-185 LEVEL IN PATIENTS WITH MALIGNANCY USING ELISA

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi-hui; WU Ping; LI Li; MIAO Yi-meng; LI Jun

    2006-01-01

    Objective: To investigate P-185 contents in serum of the normal person and cancer patients and it's the significance on prognosis of diseases. Methods: We used ELISA method to evaluate P-185 levels in 193 normal persons, 133 malignancies and 34 hepatocirrhosises were evaluated using ELISA method. Results: Normal person had lower expression of P-185. However, malignancy and hepatocirrhosis patients had a significantly higher expression level of P-185 than normal (P<0.05). Conclusion: ELISA method is an easy and reliable way to measure the level of P-185 in serum. Being a cancer marker, P-185 overexpression can be used for early diagnosis and prognosis of cancer patients.

  17. Prevalence of entamoeba histolytica and entamoeba dispar by means of microscopy and ELISA in a suburb of Lima

    International Nuclear Information System (INIS)

    Cornejo, W.; Alva, P.; Suarez, R.; Espinoza, Y.; Huiza, A.; Sevilla, C.; Naquira, C.

    1999-01-01

    To assess the prevalence of E. histolytica and E. dispar in a marginal population of Callao, Lima, using ELISAs. Two ELISAs were used, one of them for both Entamoeba species (Entamoeba-ELISA), and an E. histolytica-specific ELISA. 128 stool samples from randomized Callao inhabitants were microscopically examined. Thirteen (10%) were microscopically diagnosed as having E. histolytica or E. dispar infection; and 7 (6%) were positive to Entamoeba-ELISA (sensitivity= 54%). Five of the 115 samples without cysts of E. histolytica or E. dispar were Entamoeba ELISA positive (specificity= 96%). All samples were negative to the E. histolytica-specific ELISA. The correlation between the microscopical identification and Entamoeba-ELISA was not good, it may be due to an overvaluation of the of the morphological diagnosis. (authors)

  18. Performance of the multitarget Mikrogen Chlamydia trachomatis IgG ELISA in the prediction of tubal factor infertility (TFI) in subfertile women : Comparison with the Medac MOMP IgG ELISA plus

    NARCIS (Netherlands)

    van Ess, Eleanne F.; Ouburg, Sander; Spaargaren, Joke; Land, Jolande A.; Morre, Servaas A.

    2017-01-01

    There is a need for more accurate Chlamydia trachomatis (CT) IgG antibody tests for tubal factor infertility (TFI) diagnostics. We evaluated the predictive value for TFI of Medac ELISA plus (MOMP) and multitarget Mikrogen ELISA (MOMP-CPAF-TARP). Based on Medac ELISA plus results, 183 subfertile

  19. Bayesian estimation of sensitivity and specificity of Coxiella burnetii antibody ELISA tests in bovine blood and milk

    DEFF Research Database (Denmark)

    Paul, Suman; Toft, Nils; Agerholm, Jørgen S.

    2013-01-01

    Serological tests for Coxiella burnetii (the causative agent of Q fever) antibodies are usually based on enzyme linked immunosorbent assay (ELISA) although this method is not thoroughly evaluated. The objective of this study was to determine the sensitivity and specificity of an ELISA for detection...... lactating cows is relatively easy, non-invasive and inexpensive and hence milk ELISA may be a better option for screening lactating cows. But, blood ELISA is an option for screening non-lactating cattle....

  20. Apendicitis por Paracoccidioides brasiliensis.

    OpenAIRE

    MUÑOZ URRIBARRI, Ana Beatriz; CHAPARRO DAMMERT, Eduardo; FERRUFINO LLACH, Juan Carlos; VASQUEZ FLORES, Luciola

    2012-01-01

    La paracoccidioidomicosis es la micosis más prevalente en Sudamérica. La forma aguda afecta el sistema fagocítico mononuclear de niños y personas inmunocomprometidas. El compromiso gastrointestinal es frecuente y su patogenia implica diseminación hematógena y linfática. La linfadenomegalia abdominal causa obstrucción intestinal y abdomen agudo. En este artículo damos a conocer el caso de un niño con compromiso gastrointestinal por apendicitis. Este es el primer caso reportado de apendicitis p...

  1. Meningitis por Streptococcus suis

    OpenAIRE

    Geffner Sclarsky, D. E.; Moreno Muñoz, R.; Campillo Alpera, Mª.S.; Pardo Serrano, F.J.; Gómez Gómez, A.; Martínez-Lozano, Mª.D.

    2001-01-01

    La infección humana por Streptococcus suis (S. suis) es una zoonosis, con un riesgo ocupacional conocido y que suele presentarse como meningitis purulenta, que tiene baja mortalidad y frecuentes secuelas de hipoacusia y ataxia. Se han publicado menos de 150 casos humanos desde el informe original de hace 30 años. Hay una reconocida distribución geográfica viviendo la mayoría de los afectados en el norte de Europa y el sudeste Asiático. En España se han comunicado dos pacientes con enfermedad ...

  2. Por mil devaluados pesos

    Directory of Open Access Journals (Sweden)

    Annie Rodríguez Collázos

    2013-03-01

    Full Text Available El estudio de lo popular y lo urbano hasta ahora se ha centrado en el comportamiento y en algunas relaciones de los habitantes con su entorno. “Por mil devaluados pesos. Publicidad popular y urbana”, pretende explorar las formas de publicidad, dispersas en diferentes espacios populares y urbanos en Bogotá, identificando esquemas y formas características de sus propios códigos comunicativos; se centran en un objeto de estudio consistente en las estrategias publicitarias y los códigos comunicativos en los mensajes publicitarios populares en las subculturas de San Victorino, 7 de Agosto y Sanandresito de San José.

  3. The time course of the specific antibody response by various ELISAs in pigs experimentally infected with Toxoplasma gondii

    DEFF Research Database (Denmark)

    Lind, Peter; Haugegaard, J.; Wingstrand, Anne

    1997-01-01

    With the aim of developing routine serological tests for monitoring the Toxoplasma infection status of Danish swine herds, four ELISAs based on tachyzoite antigen were set up: (1) an indirect ELISA for IgG-antibody; (2) a blocking ELISA for antibody to the membrane antigen, P-30; (3) an indirect ...

  4. Evaluation of four indirect ELISA systems for the detection of trypanosomal antibodies in bovine serum

    International Nuclear Information System (INIS)

    Ndamkou, C.N.; Yomo, J.P.

    2000-01-01

    Four indirect-ELISA systems developed by the Joint FAO/IAEA Division for the detection of trypanosomal antibodies in bovine serum were evaluated in the field. Internal quality control data obtained were good showing that pre-coating plates with antigen increase the robustness of the assay and contribute to its standardisation. ELISA systems derived from Trypanosoma vivax antigen lysates gave a better performance than ELISA systems using T. congolense antigens. Sensitivity and specificity corresponding to the highest accuracy were 86-87% and 83-85% respectively. When comparing the two ELISA systems utilising T. vivax antigens, there was no significant difference between native and denatured antigens and diagnostic threshold was higher for denatured antigens. (author)

  5. The use of filter paper plasticized with polyvinyl alcohol-glutaraldehyde in ELISA

    Directory of Open Access Journals (Sweden)

    G.H.T.S. Barbosa

    2000-07-01

    Full Text Available F1-antigen purified from Yersinia pestis was covalently linked to 5-mm diameter filter paper discs plasticized with polyvinyl alcohol-glutaraldehyde. These discs were used both for ELISA and dot-ELISA for the detection of anti-F1 IgG in rabbits. The best conditions were achieved using 1.25 µg of F1 antigen/disc, 3% w/v skim milk in PBS as blocking agent, anti-IgG peroxidase conjugate diluted 12,000 times, and serum from rabbits immunized or not against Y. pestis, diluted 6,400 times. The absorbance values obtained from the comparative study between this procedure and conventional ELISA were not significantly different but the low cost of the reagents employed in ELISA using the filter paper discs plasticized with polyvinyl alcohol-glutaraldehyde makes this method economically attractive.

  6. A liquid phase blocking ELISA for the detection of antibodies against infectious bronchitis virus

    Directory of Open Access Journals (Sweden)

    Cardoso T.C.

    1999-01-01

    Full Text Available A liquid phase blocking ELISA (LPB-ELISA was developed for the detection and measurement of antibodies against infectious bronchitis virus (IBV. The purified and nonpurified virus used as antigen, the capture and detector antibodies, and the chicken hyperimmune sera were prepared and standardized for this purpose. A total of 156 sera from vaccinated and 100 from specific pathogen-free chickens with no recorded contact with the virus were tested. The respective serum titers obtained in the serum neutralization test (SNT were compared with those obtained in the LPB-ELISA. There was a high correlation (r2 = 0.8926 between the two tests. The LPB-ELISA represents a single test suitable for the rapid detection of antibodies against bronchitis virus in chicken sera, with good sensitivity (88%, specificity (100% and agreement (95.31%.

  7. The use of the antigen ELISA for monitoring tsetse and trypanosomosis control programmes in Zimbabwe

    Energy Technology Data Exchange (ETDEWEB)

    Ries, R; Nqindi, J [Central Veterinary Lab., Causeway, Harare (Zimbabwe)

    1997-02-01

    Blood and serum samples from cattle originating from tsetse free and tsetse infested areas were analyzed using the Buffy Coat technique and an ELISA to detect trypanosomes and trypanosomal antigens, respectively. The results of the two tests were compared and apparent sensitivity and trypanosomal prevalence were calculated. The BCT seemed to be the most suitable test to detect acute infections, while the antigen capture ELISA (Ag-ELISA) was able to detect more chronic infections. The specificity of the Ag-ELISA was found to be very good, but the sensitivity of the test should be improved. One way to detect more T. congolense and T. vivax infections was to lower the cut-off point of percent positivity from 10 to 5%. (author). 1 ref., 1 fig., 7 tabs.

  8. ELISA with double antigen sandwich for screening specific serum anti-TP antibody in blood donors

    International Nuclear Information System (INIS)

    Wang Yiqing; Shi Zhixu

    2002-01-01

    Objective: To select a sensitive and specific laboratory examination suitable for screening serum anti-TP antibody in blood donors. Methods: The serum anti-TP antibody in 11271 blood donors were detected using ELISA with double antigen sandwich and the outcomes were compared with those using RPR assay. The conflicting specimen were confirmed by repeating the test with TPHA assay. Results: The positive rates of serum anti-TP antibody by ELISA with double antigen sandwich and RPR was 0.36% (41/11271) and 0.26% (29/11271), respectively. The coincidence of the detecting outcomes by ELISA with double antigen sandwich and RPR with TPHA was 97.5% (40/41) and 63.41%(26/41) respectively. Conclusion: Compared with RPR assay, ELISA with double antigen sandwich has higher sensibility and specificity for screening serum anti-TP antibody in blood donors

  9. Inkassofirma ähvardab tuhandeid Elisa kliente aegunud nõuetega / Lauri Linnamäe

    Index Scriptorium Estoniae

    Linnamäe, Lauri

    2008-01-01

    Julianus Inkasso nõuab Elisa praegustelt ja kunagistelt klientidelt aegunud võlgade tasumist koos intressidega. Kommenteerib Urmas Volens. Vt. samas: Julianus Inkasso: aegumist saab tõlgendada mitmeti

  10. Comparison of three commercial fecal calprotectin ELISA test kits used in patients with Inflammatory Bowel Disease

    DEFF Research Database (Denmark)

    Mirsepasi-Lauridsen, Hengameh Chloé; Bachmann Holmetoft, Ulla; Halkjær, Sofie Ingdam

    2016-01-01

    OBJECTIVE: Fecal calprotectin is a noninvasive marker of intestinal inflammation used to distinguish between functional and organic bowel diseases and to evaluate disease activity among patients with Inflammatory Bowel Disease (IBD). The goal of this study was to compare three different ELISA tests...... and 18 to 67 years, respectively. Disease activity in the patients was established using the following clinical activity indices: the Simple Clinical Colitis Activity Index (SCCAI), the Harvey Bradshaw Index (HBI) and the Modified Pouchitis Disease Activity Index (MPDAI). Three ELISA calprotectin tests...... (EK-CAL, CALPRO and HK325) were performed on fecal specimens and results compared. RESULTS: The CALPRO calprotectin ELISA test was shown to have the best specificity of 96% compared to the HK325 and the EK-CAL calprotectin ELISA tests with 28% specificity and 74% specificity, respectively...

  11. Development and evaluation of porcine cysticercosis QuickELISA in Triturus EIA analyzer.

    Science.gov (United States)

    Handali, Sukwan; Pattabhi, Sowmya; Lee, Yeuk-Mui; Silva-Ibanez, Maria; Kovalenko, Victor A; Levin, Andrew E; Gonzalez, Armando E; Roberts, Jacquelin M; Garcia, Hector H; Gilman, Robert H; Hancock, Kathy; Tsang, Victor C W

    2010-01-01

    We evaluated three diagnostic antigens (recombinant GP50, recombinant T24H, and synthetic Ts18var1) for cysticercosis and found that all three performed well in detecting cysticercosis in humans and pigs in several assay formats. These antigens were adapted to a new antibody detection format (QuickELISA). With one single incubation step which involves all reactants except the enzyme substrate, the QuickELISA is particularly suited for automation. We formatted the QuickELISA for the Triturus EIA analyzer for testing large numbers of samples. We found that in QuickELISA formats rGP50 and rT24H have better sensitivity and specificity than sTs18var1 for detecting porcine cysticercosis.

  12. The use of the antigen ELISA for monitoring tsetse and trypanosomosis control programmes in Zimbabwe

    International Nuclear Information System (INIS)

    Ries, R.; Nqindi, J.

    1997-01-01

    Blood and serum samples from cattle originating from tsetse free and tsetse infested areas were analyzed using the Buffy Coat technique and an ELISA to detect trypanosomes and trypanosomal antigens, respectively. The results of the two tests were compared and apparent sensitivity and trypanosomal prevalence were calculated. The BCT seemed to be the most suitable test to detect acute infections, while the antigen capture ELISA (Ag-ELISA) was able to detect more chronic infections. The specificity of the Ag-ELISA was found to be very good, but the sensitivity of the test should be improved. One way to detect more T. congolense and T. vivax infections was to lower the cut-off point of percent positivity from 10 to 5%. (author). 1 ref., 1 fig., 7 tabs

  13. The Platelia Aspergillus ELISA in diagnosis of invasive pulmonary aspergilosis (IPA).

    Science.gov (United States)

    Siemann, M; Koch-Dörfler, M

    2001-01-01

    The sensitivity of a sandwich enzyme-linked immunosorbent assay (ELISA) for detecting Aspergillus galactomannan was evaluated with 66 serum samples and 113 specimens of the respiratory tract obtained from 52 patients with pulmonary diseases. The patients were divided into five groups: proven invasive pulmonary aspergillosis (IPA) (five patients), probable IPA (seven patients), Aspergillus colonization (eight patients) or unlikely Aspergillus infection (27 patients). Another five patients with doubtful diagnostic test results are discussed in detail. The results of the Platelia Aspergillus ELISA (Sanofi Pasteur, Freiburg, Germany) in testing specimens of the respiratory tract were 90% sensitivity in proven (serum 38%), 60% in probable (serum 37%) and 71% in Aspergillus colonization (serum 0%). Furthermore, 85% of the Aspergillus spp. from positive cultures of specimens of the respiratory tract were also detected in the ELISA. A total of 57% of the culture negative specimens of patients with a least one positive culture or proven aspergillosis in a series of specimens were positive in the ELISA.

  14. Factors Influencing the Measurement of Plasma/Serum Surfactant Protein D Levels by ELISA

    OpenAIRE

    Bratcher, Preston E.; Gaggar, Amit

    2014-01-01

    BACKGROUND: Extensive variations in human surfactant protein D (SP-D) levels in circulation as measured by ELISA exist in the published literature. In order to determine the source of these variations, factors influencing the measurement by ELISA were explored. MATERIALS AND METHODS: Peripheral blood from healthy individuals was collected into various vacutainers during the same blood draw. Recombinant SP-D was diluted into different matrices and used for a standard curve. Samples were analyz...

  15. Evaluation of immunoradiometric and ELISA versions of a microtitre plate assay for Bacillus anthracis spores

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, A P; Martin, K L; Cross, N L [Chemical Defence Experimental Establishment, Porton (UK); Drake, R G [Glasgow Univ. (UK). Inst. of Biochemistry

    1984-05-11

    Solid-phase indirectly-labelled antibody assays for Bacillus anthracis spores heat-fixed on polystyrene microtitre plates were compared as immunoradiometric assay (IRMA) and enzyme-linked immunosorbent assay (ELISA) versions. Signal-to-noise ratios were usually higher in the IRMA than in the ELISA performed under parallel conditions but replicates were more varied in the IRMA. The antigen detection threshold and resolution limit calculated after regression analysis were broadly comparable in the 2 types of assay.

  16. Refining the LPS-Antigen in Salmonella Antibody Elisa for Poultry Enhanced Specificity without Impairing Sensitivity

    DEFF Research Database (Denmark)

    Lauritsen, Klara Tølbøl; Lind, Peter; Klausen, Joan

    2014-01-01

    In the Danish serological surveillance for Salmonella in poultry (serum and egg yolk) a mix-ELISA is used, based on S. typhimurium and S. enteritidis antigens (Feld et al., 2000). When we evaluated results of the test retrospectively, over the years an unacceptably large fraction of seropositive...... findings could not be confirmed by the subsequent confirmatory bacteriological sampling in the herd. Therefore we tried to enhance specificity of the ELISA, without losing sensitivity, by refining the antigens used....

  17. Constraining stellar binary black hole formation scenarios with eLISA eccentricity measurements

    OpenAIRE

    Nishizawa, Atsushi; Sesana, Alberto; Berti, Emanuele; Klein, Antoine

    2016-01-01

    A space-based interferometer such as eLISA could observe few to few thousands progenitors of black hole binaries (BHBs) similar to those recently detected by Advanced LIGO. Gravitational radiation circularizes the orbit during inspiral, but some BHBs retain a measurable eccentricity at the low frequencies where eLISA is most sensitive. The eccentricity of a BHB carries precious information about its formation channel: BHBs formed in the field, in globular clusters, or close to a massive black...

  18. Rabbit haemorrhagic disease: advantages of cELISA in assessing immunity in wild rabbits (Oryctolagus cuniculus).

    Science.gov (United States)

    Zheng, Tao; Parkes, John P

    2011-12-15

    Rabbit haemorrhagic disease (RHD) is an acute fatal disease of domestic and wild European rabbits (Oryctolagus cuniculus) caused by RHD virus (RHDV). Accurate assessment of immunity is of great importance for the conservation and control of wild rabbits. We evaluated a competitive ELISA (cELISA) against isotype ELISAs for assessing the protective immunity against the disease by challenging 50 wild-caught rabbits with a lethal dose of RHDV. Death or survival to the challenge was used as a criterion to determine the performance characteristics of the assay for the assessment of immunity in rabbits. At 1:10 dilution, a serum exhibiting ≥ 25% inhibition (1:10(25)) was regarded as the presence of RHDV-specific antibodies. Eleven of 16 (68.8%) rabbits with antibodies at 1:10(25) (<1:40) died of RHD. When the cut-off was moved from 25% to 50% inhibition (1:10(50)) at 1:10 serum dilution, the assay sensitivity, specificity and accuracy for the protective immunity were improved from 84%, 54.2% and 69.4% to 84%, 100% and 91.8%, respectively. We also demonstrated at the epitope amino acid sequence level why the presence of the RHDV-cross reactive benign rabbit calicivirus, which interfered with isotype ELISAs, had little impact on the specificity of the cELISA for the diagnosis of RHDV infection. The presence of RHDV-specific antibody at 1:10(50) by the cELISA is a reliable indicator for the protective immunity. In contrast to isotype ELISAs, the cELISA is a valuable specific tool for monitoring the herd immunity to RHD for the conservation and management of wild rabbits in the field. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Anti-signal recognition particle autoantibody ELISA validation and clinical associations.

    Science.gov (United States)

    Aggarwal, Rohit; Oddis, Chester V; Goudeau, Danielle; Fertig, Noreen; Metes, Ilinca; Stephens, Chad; Qi, Zengbiao; Koontz, Diane; Levesque, Marc C

    2015-07-01

    The aim of this study was to develop and validate a quantitative anti-signal recognition particle (SRP) autoantibody serum ELISA in patients with myositis and longitudinal association with myositis disease activity. We developed a serum ELISA using recombinant purified full-length human SRP coated on ELISA plates and a secondary antibody that bound human IgG to detect anti-SRP binding. Protein immunoprecipitation was used as the gold standard for the presence of anti-SRP. Serum samples from three groups were analysed: SRP(+) myositis subjects by immunoprecipitation, SRP(-) myositis subjects by immunoprecipitation and non-myositis controls. The ELISA's sensitivity, specificity, positive predictive value and negative predictive value were evaluated. Percentage agreement and test-retest reliability were assessed. Serial samples from seven SRP immunoprecipitation-positive subjects were also tested, along with serum muscle enzymes and manual muscle testing. Using immunoprecipitation, we identified 26 SRP(+) myositis patients and 77 SRP(-) controls (including 38 patients with necrotizing myopathy). Non-myositis control patients included SLE (n = 4) and SSc (n = 7) patients. Anti-SRP positivity by ELISA showed strong agreement (97.1%) with immunoprecipitation (κ = 0.94). The sensitivity, specificity, positive predictive value, and negative predictive value of the anti-SRP ELISA were 88, 100, 100 and 96, respectively. The area under the curve was 0.94, and test-retest reliability was strong (r = 0.91, P < 0.001). Serial samples showed that anti-SRP levels paralleled changes in muscle enzymes and manual muscle testing. We developed a quantitative ELISA for detecting serum anti-SRP autoantibodies and validated the assay in myositis. Longitudinal assessment of SRP levels by ELISA may be a useful biomarker for disease activity. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions

  20. Investigation of enrofloxacin residues in broiler tissues using ELISA and LC-MS/MS.

    Science.gov (United States)

    Panzenhagen, Pedro Henrique N; Aguiar, Waldemir S; Gouvêa, Raquel; de Oliveira, Andréa M G; Barreto, Fabiano; Pereira, Virgínia L A; Aquino, Maria Helena C

    2016-01-01

    This study investigated the efficiency of an enrofloxacin ELISA test kit to detect the presence of enrofloxacin residues in broiler tissues compared with LC-MS/MS. Broiler tissues from 72 samples consisting of 60 breast muscle, six pools of livers (500 g each) and six pools of kidneys (500 g each) were obtained from six different slaughterhouses. Breast muscle from 10 carcasses and pools of livers and kidneys from approximately 200 carcasses of the same flock were collected from each slaughterhouse. ELISA and HPLC were used to identify and quantify the contamination of the samples with enrofloxacin. A total of 72% of the analysed samples contained enrofloxacin residues detected by the ELISA and 22.2% were detected by LC-MS/MS. The mean values of enrofloxacin contamination found in chicken breast by ELISA and HPLC were 8.63 and 12.25 μg kg(-1), respectively. None of the samples exceeded the maximum limit of 100 μg kg(-1) by both methods set by the European Union as well as the Brazilian Agriculture Ministry. All positive samples for enrofloxacin residues detected by LC-MS/MS were also positive by ELISA. These data confirm the efficiency of the ELISA test, and suggest its use as a screening method for enrofloxacin residues in poultry tissues due to its quick results, low price and ease of applicability.

  1. Seroprevalence of Toxoplasma gondii in southern districts of Tamil Nadu using IgG-ELISA.

    Science.gov (United States)

    Sucilathangam, G; Palaniappan, N; Sreekumar, C; Anna, T

    2012-10-01

    The present study was conducted to assess the seroprevalence of Toxoplasma gondii in and around Tirunelveli by in-house IgG assay using ELISA. Serum samples from 175 immunodeficient and 175 immunocompetent patients were collected at Tirunelveli district, Tamil Nadu from May 2006 to October 2007. They were subjected into in-house IgG assay using enzyme-linked immune sorbent assay (ELISA) in which tachyzoite soluble antigen derived from solubilised whole organisms was used. Out of 350 patients tested by IgG ELISA, 46 patients (13.14%) had antibodies for toxoplasmosis with mean OD value of 0.2 ± 0.073 and the OD value ranged from 0.144 to 0.444. Among the immunocompetent group of 175 patients, 19 patients (10.86%) had antibodies to toxoplasmosis whereas, in immunodeficient group of 175 patients, 27 patients (15.43%) had antibodies for toxoplasmosis. There was no statistical difference (P > 0.05) between the immunocompetent and immunodeficient group. The sensitivity and specificity of IgG ELISA in detecting toxoplasmosis was 90 and 100%, respectively. The overall seroprevalence of toxoplasmosis in and around Tirunelveli district of Tamil Nadu was 13.14% based on IgG ELISA. The study has proved ELISA to be a sensitive and specific procedure for the serodiagnosis of toxoplasmosis.

  2. Consistency of direct microscopic examination and ELISA in detection of Giardia in stool specimen among children

    Directory of Open Access Journals (Sweden)

    Zohreh Torabi

    2014-09-01

    Full Text Available Objective: To investigate the consistency of direct microscopic examination and ELISA for determination of Giadia in stool specimen. Method: Study population consisted of children with any clinical symptoms of Giardia infestation since last two weeks. Fresh stool specimen was collected from each child. The stools specimens were assessed by two methods of direct microscopic examination and ELISA.The degree of agreement between direct stool exam and ELISA was calculated by Cohen's kappa coefficient. Results: In this study, 124 children with age range 2-12 years were investigated. A total of 64 (61.7% and 79 (65.7% of children had Giardia by direct stool exam and ELISA test respectively. There was association between frequency of constipation and Giardia infection (P=0.036. The Cohen's kappa coefficient calculated for degree of agreement between direct stool exam and ELISA showed κ=0.756 (P<0.001. Conclusions: The frequency of Giardia infection in symptomatic children was high and there was high agreement rate between ELISA and direct stool smear.

  3. Constraining stellar binary black hole formation scenarios with eLISA eccentricity measurements

    Science.gov (United States)

    Nishizawa, Atsushi; Sesana, Alberto; Berti, Emanuele; Klein, Antoine

    2017-03-01

    A space-based interferometer such as the evolved Laser Interferometer Space Antenna (eLISA) could observe a few to a few thousands of progenitors of black hole binaries (BHBs) similar to those recently detected by Advanced LIGO. Gravitational radiation circularizes the orbit during inspiral, but some BHBs retain a measurable eccentricity at the low frequencies where eLISA is the most sensitive. The eccentricity of a BHB carries precious information about its formation channel: BHBs formed in the field, in globular clusters, or close to a massive black hole (MBH) have distinct eccentricity distributions in the eLISA band. We generate mock eLISA observations, folding in measurement errors, and using a Bayesian model selection, we study whether eLISA measurements can identify the BHB formation channel. We find that a handful of observations would suffice to tell whether BHBs were formed in the gravitational field of an MBH. Conversely, several tens of observations are needed to tell apart field formation from globular cluster formation. A 5-yr eLISA mission with the longest possible armlength is desirable to shed light on BHB formation scenarios.

  4. Villa Elisa Rice Cooperative, a good example of Entre Rios cooperative tradition (Argentina La Cooperativa Arroceros Villa Elisa, un buen ejemplo de la tradición cooperativista de Entre Ríos (Argentina

    Directory of Open Access Journals (Sweden)

    Graciela Mateo

    2011-01-01

    Full Text Available Historians recognize Entre Rios province as the birthplace of colonization but it is also there that, since the beginning of the twentieth century, agricultural cooperatives providing important services to partners in sourcing, marketing and industrialization have developed. Cooperative aid have brought about a more rational use of the land, increased turnover, improved product quality, efficient use of capital and rising demand due to expanding markets, different services that each farmer by itself could not reach. This article proposes to analyse the trajectory of a rice producers cooperative -founded in the 1970's - located in the town of Villa Elisa, Entre Rios province, which in greater or lesser degree has been giving these benefits and ranks nowadays as the third national rice exporter and occupies the first place in cooperative management. As well as economic issues, particular attention will be given to the institutional articulation of the company and the introduccion of organizational changes.Así como la Historia reconoce a Entre Ríos como cuna de la colonización, es también en esta provincia donde desde el comienzo del siglo XX se desarrolla el cooperativismo agrario que presta importantes servicios al asociado en materia de abastecimiento, comercialización y transformación. Prestación que se traduce en un uso más racional de la tierra, un mayor volumen de negocios, el mejoramiento en la calidad del producto, la utilización eficiente del capital, el aumento de la demanda por la ampliación de los mercados y la introducción de servicios que cada agricultor por si sólo no podría alcanzar. El presente artículo se propone analizar la trayectoria de una cooperativa arrocera -fundada en la década de 1970- ubicada en la localidad entrerriana de Villa Elisa que en mayor o menor media ha ido cumpliendo con esas prestaciones y que hoy se posiciona como el tercer exportador nacional de arroz y el primero de gestión cooperativa

  5. Sepsis por shigella flexneri

    Directory of Open Access Journals (Sweden)

    César Cabrera C

    2005-04-01

    Full Text Available Se presenta un caso raro de sepsis por Shigella flexneri en una paciente de 45 años de edad quien estando hospitalizada para el estudio de un tumor cerebral, requirió el uso de manitol y dosis altas de corticoides; luego de ello presenta deposiciones líquidas con moco y sangre, desarrolla síndrome de respuesta inflamatoria sistémica, luego se aísla Shigella flexneri en el hemocultivo; recibió tratamiento antibiótico con ciprofloxacina. Se describen las características del caso y se comenta de acuerdo con la revisión de literatura.

  6. Portable exhausters POR-004 SKID B, POR-005 SKID C, POR-006 SKID D storage plan

    International Nuclear Information System (INIS)

    Nelson, O.D.; Keller, G.M.

    1997-01-01

    This document provides a storage plan for portable exhausters POR-004 SKID B, POR-005 SKID C, AND POR-006 SKID D. The exhausters will be stored until they are needed by the TWRS (Tank Waste Remediation Systems) Saltwell Pumping Program. The storage plan provides criteria for portable exhauster storage, periodic inspections during storage, and retrieval from storage

  7. Estandarización de la técnica de ELISA para el diagnóstico de Toxocariasis humana

    Directory of Open Access Journals (Sweden)

    Yrma Espinoza

    2003-03-01

    Full Text Available Objetivo: Estandarizar la técnica ELISA para el diagnóstico de infección humana por Toxocara canis con antígeno excretado-secretado preparado en nuestro medio. Material y Métodos: Se colectó huevos de T. canis y se les incubó con formol (2% a 28°C hasta obtener larvas de tercer estadio, las que luego de ser liberadas fueron incubadas en RPMI a 37°C por 7 días; se reemplazó el medio por otro similar y almacenó a -20°C. Se concentró el antígeno y se dosó proteínas. Para la técnica de ELISA se utilizó sueros de pacientes con toxocariasis y de niños recién nacidos, como controles positivos y negativos, respectivamente, diluidos desde ¼ hasta 1/1024. Se sensibilizó placas de poliestireno con varias concentraciones de antígeno, utilizándose conjugado de peroxidasa e IgG de carnero anti IgG humana y sustrato OPD. Se realizó lectura de absorbancia a 492 nm con espectrofotómetro (Multiskan plus labsystems, siendo el punto de corte el promedio aritmético de la absorbancia de los sueros negativos más 3 desviaciones estándar. Resultados: La concentración óptima del antígeno fue 50 ug/mL, la dilución del suero 1/128, la dilución del conjugado 1/1000 con densidad óptica mayor a 0,241. Conclusiones: La técnica de ELISA para diagnóstico serológico de infección humana por Toxocara canis podría ser utilizada en estudios epidemiológicos en nuestro país. Queda pendiente la evaluación de su eficacia en futuros estudios.

  8. Development, standardisation and validation of ELISA methods to improve the control of trypanosomosis

    International Nuclear Information System (INIS)

    Rebeski, D.E.; Winger, E.M.; Robinson, M.M.; Dwinger, R.H.; Crowther, J.R.

    2000-01-01

    During the period from 1995 to 2000, comprehensive laboratory and field studies on enzyme-linked immunosorbent assay (ELISA) methods for detection of trypanosomal antibodies and antigens were undertaken to improve the proficiency of diagnostic laboratories involved in control of trypanosomosis in the tropics. The work was initiated by the FAO/IAEA through the Coordinated Research Programme D3.20.13 and undertaken in close collaboration with Research Agreement Holders and Research Contract Holders. Initially, the CRP facilitated the field evaluation of three direct sandwich antigen detection ELISAs based on monoclonal antibodies. Diagnostic laboratories were supported with ELISA equipment, disposables, and training. ELISA reagents were produced in sufficient quantities and distributed in a standardised kit format. As a result of the laboratory and field evaluation studies, the assays were found unreliable for trypanosomosis control and rejected for routine use in diagnostic laboratories. At that time, no standardised ELISA system was available for trypanosomosis that was considered suitable for distribution and use under tropical conditions. Through the CRP, a new generation of standardised antibody ELISAs were developed and established using a novel approach, namely the use of antigen-precoated ELISA plates. In addition, the potential of native and denatured trypanosomal antigens as diagnostic candidates was examined. In-house and field evaluation studies in the tropics demonstrated that a reasonable robustness with an acceptable diagnostic assay proficiency was achieved by means of utilising plates precoated with denatured antigens. Moreover, a data charting method for continuous monitoring of the operational performance of the ELISAs was developed and established. It was routinely used as remote control and follow up tool saving the need for costly expert missions to the diagnostic laboratories during the assay validation period. In parallel, preliminary studies

  9. Comparative Diagnosis of Serum IgG1 and Coproantigen ELISA for Fasciolosis Detection of Goats in Mexico

    Science.gov (United States)

    Molina-Mendoza, Pedro; Hernández-Guzmán, Karina; Olivares-Pérez, Jaime; Sarracent-Pérez, Jorge; Zumaquero-Ríos, José

    2016-01-01

    The objective of present study was to determine the prevalence of natural caprine fasciolosis in the Mixteca region of Mexico using coproantigen and serum IgG1 ELISA tests for comparative purposes. A total of 1070 serum and faecal samples were analyzed for IgG1 antibodies and coproantigens, using ELISA with E/S products as antigen and a monoclonal antibody-based sandwich ELISA. Prevalence of 73.46% was found using the serological ELISA and a percentage of 77.20 was found for coproantigen ELISA. The diagnostic sensitivity and specificity for serum ELISA were 86.7% and 96.4%, and for the coproantigen ELISA they were 93.1% and 97.8%, respectively. The seropositive samples were further categorized as low, medium, or high positivity. Results show a great proportion of low and medium positive goats when the serum ELISA test was used. Correlation coefficients between coproantigens and seropositivity were statistically significant (P < 0.01) for low seropositivity (r = 0.93) and medium seropositivity (r = 0.84). The accuracy of faecal antigen ELISA was higher compared to indirect ELISA serological test. Two ELISAs were shown to be useful for demonstrating the current status of F. hepatica infection in the endemic areas and can be employed in studies on epidemiology as well as anthelmintics treatment for preventing economic loss and the risk of transmission to humans. PMID:27563665

  10. Diagnosis of Caprine Arthritis Encephalitis Virus infection in dairy goats by ELISA, PCR and Viral Culture.

    Science.gov (United States)

    Panneum, S; Rukkwamsuk, T

    2017-03-01

    For preventive and control strategies of Caprine Arthritis Encephalitis Virus (CAEV) infection in dairy goats, performance of the available diagnostic tests was described as one of the most important and necessary aspects. The study aimed at evaluating the diagnostic test performance, including PCR, ELISA and viral culture, for CAEV infection in dairy goats in Thailand. Blood samples of 29 dairy goats from five low- to medium-prevalence herds and one very low-prevalence herd were collected for PCR and ELISA methods. The performance of these two diagnostic methods was evaluated by comparing with cytopathic effects (CPE) in the co-cultivation of CAEV and primary synovial cells. Results indicated that sensitivity, specificity were, respectively, 69.6%, 100%, for PCR; and 95.7%, 83.3% for ELISA. The PCR assay tended to have lower sensitivity and higher specificity than ELISA. When multiple tests were applied, parallel testing provided sensitivity and specificity of 98.7% and 83.3%, while series testing showed sensitivity and specificity of 66.6% and 100% respectively. These results indicated that combination of ELISA and PCR provided some advantages and possibly offered optimal methods to detect CAEV-infected goats. Kappa value of the agreement between PCR and ELISA test was 0.34, indicating fair agreement. Regarding the possibility of antigenic variation between CAEV strains used in both PCR and ELISA assays, the actual circulating CAEV strain should be reviewed in order to develop and enhance the diagnostic tests using the CAE viral antigens derived from specific local strains of Thailand.

  11. Development and primary application of ELISA method for detecting residual calf serum protein

    International Nuclear Information System (INIS)

    Li Hua; Yu Jiankun; Hong Chao; Long Ruixiang; Zhai Yougang; Xu Qiongfang; Cui Pingfang; Ding Xuefeng; Xie Zhongping

    2005-01-01

    To develop a new DAS-ELISA (double antibody sandwich ELISA) kit for detecting residual calf serum protein (CSP) in vaccines, calf sera from different district were pooled and used to immunize rabbits and hens respectively. Then, the IgY from yolk and the anti-CSP IgG from rabbit were separated and purified. The purified IgY was used as the coating antibody, and purified rabbit anti-CSP IgG was labeled by HRP. The optimal concentration of IgY was 25-30 μg/mL. The coating buffer was 0.01mol/L PBS(pH7.4) containing 0.4% glutin. The optimal dilutions of HRP-IgG were from 1:2000 to 1:3000. The sensitivity of this ELISA method was higher (up to 2.5μg/mL) than that of current RPHA, the variation coefficient was about 6.3%-9.4%, and the recovery rate was 90.4%-112.8%. Furthermore, there was no cross-reaction with sera of pig, monkey and guinea pig. Twenty lots of vaccines with Al(OH) 3 or without Al(OH) 3 were tested by ELISA and RPHA respectively. The results proved that the adjuvant of Al(OH) 3 had fewer influence on ELISA than on RPHA, the variation of PRHA among different lots of vaccines was more significant than ELISA. The ELISA method is a highly sensitive and useful method to detect CSP in vaccines. (authors)

  12. Control Multivariable por Desacoplo

    Directory of Open Access Journals (Sweden)

    Fernando Morilla

    2013-01-01

    Full Text Available Resumen: La interacción entre variables es una característica inherente de los procesos multivariables, que dificulta su operación y el diseño de sus sistemas de control. Bajo el paradigma de Control por desacoplo se agrupan un conjunto de metodologías, que tradicionalmente han estado orientadas a eliminar o reducir la interacción, y que recientemente algunos investigadores han reorientado con objetivos de solucionar un problema tan complejo como es el control multivariable. Parte del material descrito en este artículo es bien conocido en el campo del control de procesos, pero la mayor parte de él son resultados de varios años de investigación de los autores en los que han primado la generalización del problema, la búsqueda de soluciones de fácil implementación y la combinación de bloques elementales de control PID. Esta conjunción de intereses provoca que no siempre se pueda conseguir un desacoplo perfecto, pero que sí se pueda conseguir una considerable reducción de la interacción en el nivel básico de la pirámide de control, en beneficio de otros sistemas de control que ocupan niveles jerárquicos superiores. El artículo resume todos los aspectos básicos del Control por desacoplo y su aplicación a dos procesos representativos: una planta experimental de cuatro tanques acoplados y un modelo 4×4 de un sistema experimental de calefacción, ventilación y aire acondicionado. Abstract: The interaction between variables is inherent in multivariable processes and this fact may complicate their operation and control system design. Under the paradigm of decoupling control, several methodologies that traditionally have been addressed to cancel or reduce the interactions are gathered. Recently, this approach has been reoriented by several researchers with the aim to solve such a complex problem as the multivariable control. Parts of the material in this work are well known in the process control field; however, most of them are

  13. ELISA for detection of variant rabbit haemorrhagic disease virus RHDV2 antigen in liver extracts.

    Science.gov (United States)

    Dalton, K P; Podadera, A; Granda, V; Nicieza, I; Del Llano, D; González, R; de Los Toyos, J R; García Ocaña, M; Vázquez, F; Martín Alonso, J M; Prieto, J M; Parra, F; Casais, R

    2018-01-01

    The emergence and rapid spread of variant of the rabbit hemorrhagic disease virus (RHDV2) require new diagnostic tools to ensure that efficient control measures are adopted. In the present study, a specific sandwich enzyme-linked immunosorbent assay (ELISA) for detection of RHDV2 antigens in rabbit liver homogenates, based on the use of an RHDV2-specific monoclonal antibody (Mab) 2D9 for antigen capture and an anti-RHDV2 goat polyclonal antibody (Pab), was developed. This ELISA was able to successfully detect RHDV2 and RHDV2 recombinant virions with high sensitivity (100%) and specificity (97.22%). No cross-reactions were detected with RHDV G1 viruses while low cross-reactivity was detected with one of the RHDVa samples analyzed. The ELISA afforded good repeatability and had high analytical sensitivity as it was able to detect a dilution 1:163,640 (6.10ng/mL) of purified RHDV-N11 VLPs, which contained approximately 3.4×10 8 molecules/mL particles. The reliable discrimination between closely related viruses is crucial to understand the epidemiology and the interaction of co-existing pathogens. In the work described here we design and validate an ELISA for laboratory based, specific, sensitive and reliable detection of RHDVb/RHDV2. This ELISA is a valuable, specific virological tool for monitoring virus circulation, which will permit a better control of this disease. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. His-tag ELISA for the detection of humoral tumor-specific immunity

    Directory of Open Access Journals (Sweden)

    Disis Mary L

    2008-05-01

    Full Text Available Abstract Background The application of high throughput molecular techniques such as SEREX are resulting in the identification of a multitude of tumor associated antigens. As newly identified antigens are incorporated into a variety of clinical trials, standardization of immunologic monitoring methods becomes increasingly important. We questioned whether mammalian cell expression of a histadine-linked human protein could be used to produce antigen suitable for detecting tumor-specific humoral immunity and whether such an assay could be amenable to standardization for clinical use. Methods We designed a his-tagged capture ELISA based on lysate from genetically engineered CHO cells for detection of antibodies to insulin-like growth factor binding protein 2, a novel tumor antigen. We performed technical and preliminary clinical validation studies, including comparison to a standard indirect ELISA based on commercially prepared recombinant antigen. Results The his-tagged capture ELISA could be standardized. Precision experiments resulted in CVs 2 values of 0.99. In comparison to Western blot analysis, his-tag and indirect ELISA accurately identified 88% and 93% of samples, respectively. Sample concordance between capture and indirect assays was highly significant (p = 0.003. Furthermore, significantly greater levels of IGFBP-2 antibody immunity were found in cancer patients compared to normal controls (p = 0.008. Conclusion A genetically engineered cell lysate based ELISA can be amenable to standardization and can detect increased levels of antibody immunity to tumor-associated antigen in cancer patients compared to non tumor-bearing healthy controls.

  15. A Monoclonal Antibody-Based ELISA for Multiresidue Determination of Avermectins in Milk

    Directory of Open Access Journals (Sweden)

    Wenxiao Jiang

    2012-06-01

    Full Text Available Due to the widespread use and potential toxicity of avermectins (AVMs, multi-residue monitoring of AVMs in edible tissues, especially in milk, has become increasingly important. With the aim of developing a broad-selective immunoassay for AVMs, a broad-specific monoclonal antibody (Mab was raised. Based on this Mab, a homologous indirect enzyme-linked immunosorbent assay (ELISA for the rapid detection of AVMs in milk was developed. Under the optimized conditions, the IC50 values in assay buffer were estimated to be 3.05 ng/mL for abamectin, 13.10 ng/mL for ivermectin, 38.96 ng/mL for eprinomectin, 61.00 ng/mL for doramectin, 14.38 ng/mL for emamectin benzoate. Detection capability (CCβ of the ELISA was less than 5 ng/mL and 2 ng/mL in milk samples prepared by simple dilution and solvent extraction, respectively. The optimized ELISA was used to quantify AVMs in milk samples spiked at different amounts. The mean recovery and coefficient of variation (CV were 95.90% and 15.42%, respectively. The Mab-based ELISA achieved a great improvement in AVMs detection. Results proved this broad-selective ELISA would be useful for the multi-residue determination of AVMs in milk without purification process.

  16. Development of indirect sandwich ELISA for determination of excretory-secretory antigens of Fasciola hepatica

    Directory of Open Access Journals (Sweden)

    Libertad Alzamora-Gonzales

    2016-05-01

    Full Text Available Fasciolosis is a cosmopolitan parasitosis medical-veterinary importance caused by Fasciola hepatica, which affects sheep, goats and cattle; and it affects man accidentally causing an epidemic-endemic infection difficult to diagnose. The aim was to develop an indirect sandwich ELISA with 3 antibodies for detecting excretory-secretory antigens of Fasciola hepatica (ESFh. For the development of indirect sandwich ELISA were used, as capture antibody, mouse polyclonal antibodies anti ESFh and polyclonal antibodies rabbit anti-ESFh as detection antibody, at the concentrations of 10 and 5 µg/mL respectively. The conjugate used was mouse monoclonal anti- total immunoglobulins rabbit linked to peroxidase (1/1000. Were analized 31 sheep fecal samples, and the results were compared with those obtained by direct coproparasitological examination (DC and counterimmunoelectrophoresis (CIEP. The detection limit obtained for indirect sandwich ELISA was 100 ng/mL. The test had a 100% sensitivity, 96.6% specificity, positive and negative predictive values of 50% and 96.6% respectively, in relation to DC test. Comparing with CIEP the specificity obtained for indirect sandwich ELISA was 93.5% and a negative predictive value of 100%. We concluded that indirect sandwich ELISA designed is able to detect metabolic antigens in ovine feces samples and can be used for Fasciola hepatica diagnosis.

  17. Detection of ciguatoxin in fish tissue using sandwich ELISA and neuroblastoma cell bioassay.

    Science.gov (United States)

    Empey Campora, Cara; Dierking, Jan; Tamaru, Clyde S; Hokama, Yoshitsugi; Vincent, Douglas

    2008-01-01

    The applicability of a new enzyme-linked immunoassay (ELISA) for detecting ciguatoxin (CTX) in fish tissue was evaluated by testing three fish species commonly implicated in ciguatera fish poisoning in Hawaii. A total of 164 individual almaco jack (Seriola rivoliana) and greater amberjack (S. dumerili) and a total of 175 individuals of the blue-spotted grouper (Cephalopholis argus) were caught at various locations in the Hawaiian Islands. Muscle tissue from each individual was assessed for the presence of CTX using two methods: a semi-quantitative ELISA that was recently developed for detecting picogram levels of CTX in fish extract and a neuroblastoma (NB) cell assay commonly used to screen for marine toxins in fish. Results of the tests were highly correlated, with the ELISA indicating the presence of CTX in 9.4% of all fish samples, and the NB assay indicating toxicity in 6.8% of the fish samples. We conclude that the ELISA produces reliable and accurate results that are consistent with those provided by the accepted NB assay and that the ELISA has potential for future applications in screening fish populations for CTX.

  18. Comparison of monomeric and polymeric horseradish peroxidase as labels in competitive ELISA for small molecule detection

    International Nuclear Information System (INIS)

    Li, Dongyang; Ying, Yibin; Wu, Jian; Niessner, Reinhard; Knopp, Dietmar

    2013-01-01

    We have developed a simple and sensitive competitive enzyme-linked immunosorbent assay (ELISA) to determine aflatoxin B1 (as a model small analyte) and using streptavidin-polymeric horseradish peroxidase complex (SApolyHRP) as a label for signal amplification. The performance of the assay was evaluated by comparing it with the classical indirect competitive ELISA using HRP labeled anti-mouse IgG as the tracer antibody. The results indicate that the SApolyHRP-based competitive ELISA exhibits a typically 2.4-fold steeper slope of the linear working range of the calibration curve compared to the monomeric HRP based classical ELISA, i.e., the sensitivity was increased. The SApolyHRP conjugate causes a typically 19-fold stronger signal generation in comparison to the traditional HRP labeled anti-mouse IgG at the same concentration (25 ng mL −1 ). Moreover, the SApolyHRP-based assay has a much wider linear range and a 3.8-fold better signal-to-noise ratio. Considering its simplicity, sensitivity and ease of operation, this competitive ELISA is considered to be a promising tool for small molecule immuno detection. (author)

  19. Comparison of viral RNA electrophoresis and indirect ELISA methods in the diagnosis of human rotavirus infection

    Energy Technology Data Exchange (ETDEWEB)

    Avendano, L F; Dubinovsky, S; James, Jr, H D

    1984-01-01

    A total of 177 stool samples from Chilean diarrhea patients under two years of age were tested for rotavirus by two methods - the indirect enzyme-linked immunosorbent assay (indirect ELISA) and viral RNA electrophoresis in agarose gels (v RNA EPH). Fifty of the specimens came from patients with acute diarrhea and 127 came from patients with protracted diarrhea. The indirect ELISA testing was performed at the National Institutes of Health in the United States: the electrophoretic testing was carried out in Santiago, Chile by the authors. The electrophoretic method detected rotavirus in 36% of the acute samples and 25% of the samples from protracted cases, while the indirect ELISA method detected rotavirus in higher percentages of samples - 46% and 38%, respectively. These results support the conclusion that v RNA EPH is a less sensitive method for detecting rotavirus than the indirect ELISA. Nevertheless, the former method's high specificity, ease of application, and low cost make it a worthwhile alternative to indirect ELISA. Thus, considering the important role played by rotavirus in infant diarrhea and the need for a diagnostic technique that can be incorporated into the routines of medical center laboratories in developing countries, there is good reason to conclude that v RNA EPH is a useful tool for studying rotavirus diarrhea. 18 refs, 3 tabs. Also published in the Bol. Oficina Sanit. Panam. (1984) v. 97(1), p. 1-7 (In Spanish).

  20. Preparation and Characteristic of Dextran-BSA Antibody and Establishment of its ELISA Immunoassay.

    Science.gov (United States)

    Xie, Zhen-ming; Yu, Lin; Fang, Li-sha

    2015-01-01

    The enzyme-linked immunosorbent assay (ELISA) is a potential tool for the determination of dextran. In this study, dextran neoglycoprotein antigens were prepared by Reductive Amination method, and were confirmed by SDS-PAGE and free amino detection. The impact factors such as different oxidation degree of dextran, the conjugate reaction time to BSA were investigated. The best preparation conditions were obtained (n(dextran)/n(oxidant) of NaIO4 = 1/120, the reaction time of 24 h), and the antigen with best combination with standard was obtained. The antigens interacted with standard antibody and were evaluated through ELISA. The immunogen was immunized with white rabbits to obtained antibody, respectively. A general and broad class-specific ELISA immunoassay was developed for dextran detection according to ELISA theory. The optimized conditions of assay used coating antigen at 10 μg/mL, reaction time of antibody and rabbit-anti-bovine IgG in 45 min, blocking reagents with 5% calf serum. The developed ELISA detection method with good linear and accuracy was put to use for quantitative analysis of dextran T40 in commercial sugarpractical for detection of dextran.

  1. Short communication: ELISA system for screening of bovine mastitis caused by Prototheca zopfii.

    Science.gov (United States)

    Kano, Rui; Sato, Ayano; Sobukawa, Hideto; Sato, Yuko; Ito, Takaaki; Suzuki, Kazuyuki; Hasegawa, Atsuhiko; Kamata, Hiroshi

    2016-08-01

    Prototheca zopfii is an achlorophyllic alga that causes bovine mastitis, resulting in a reduction in milk production and the secretion of thin, watery milk with white flakes. This study evaluated the use of an ELISA system for distinguishing cows with mastitis due to P. zopfii genotype 2 from healthy cows and cows with chronic candidal mastitis. We also investigated the transitional changes of specific antibody titers in healthy cows injected with inactivated P. zopfii genotype 2 cells. The ELISA system exhibited the highest sensitivity (94%) and specificity (100%) for chronic protothecal mastitis when the positive cutoff value was set at 43.4 ELISA units. Anti-protothecal IgG titers were positive in all cows after they were inoculated with inactivated P. zopfii genotype 2 cells. These results indicated that ELISA detection of anti-protothecal IgG in serum provided specificity and sensitivity sufficient for diagnosing protothecal mastitis. Thus, an ELISA system incorporating this specific antiserum is expected to be valuable for definitive field-based diagnosis of bovine mastitis due to P. zopfii genotype 2. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  2. Comparison of viral RNA electrophoresis and indirect ELISA methods in the diagnosis of human rotavirus infection

    International Nuclear Information System (INIS)

    Avendano, L.F.; Dubinovsky, S.

    1984-01-01

    A total of 177 stool samples from Chilean diarrhea patients under two years of age were tested for rotavirus by two methods - the indirect enzyme-linked immunosorbent assay (indirect ELISA) and viral RNA electrophoresis in agarose gels (v RNA EPH). Fifty of the specimens came from patients with acute diarrhea and 127 came from patients with protracted diarrhea. The indirect ELISA testing was performed at the National Institutes of Health in the United States: the electrophoretic testing was carried out in Santiago, Chile by the authors. The electrophoretic method detected rotavirus in 36% of the acute samples and 25% of the samples from protracted cases, while the indirect ELISA method detected rotavirus in higher percentages of samples - 46% and 38%, respectively. These results support the conclusion that v RNA EPH is a less sensitive method for detecting rotavirus than the indirect ELISA. Nevertheless, the former method's high specificity, ease of application, and low cost make it a worthwhile alternative to indirect ELISA. Thus, considering the important role played by rotavirus in infant diarrhea and the need for a diagnostic technique that can be incorporated into the routines of medical center laboratories in developing countries, there is good reason to conclude that v RNA EPH is a useful tool for studying rotavirus diarrhea. (author)

  3. Development of a species-specific coproantigen ELISA for human Taenia solium taeniasis.

    Science.gov (United States)

    Guezala, Maria-Claudia; Rodriguez, Silvia; Zamora, Humberto; Garcia, Hector H; Gonzalez, Armando E; Tembo, Alice; Allan, James C; Craig, Philip S

    2009-09-01

    Taenia solium causes human neurocysticercosis and is endemic in underdeveloped countries where backyard pig keeping is common. Microscopic fecal diagnostic methods for human T. solium taeniasis are not very sensitive, and Taenia saginata and Taenia solium eggs are indistinguishable under the light microscope. Coproantigen (CoAg) ELISA methods are very sensitive, but currently only genus (Taenia) specific. This paper describes the development of a highly species-specific coproantigen ELISA test to detect T. solium intestinal taeniasis. Sensitivity was maintained using a capture antibody of rabbit IgG against T. solium adult whole worm somatic extract, whereas species specificity was achieved by utilization of an enzyme-conjugated rabbit IgG against T. solium adult excretory-secretory (ES) antigen. A known panel of positive and negative human fecal samples was tested with this hybrid sandwich ELISA. The ELISA test gave 100% specificity and 96.4% sensitivity for T. solium tapeworm carriers (N = 28), with a J index of 0.96. This simple ELISA incorporating anti-adult somatic and anti-adult ES antibodies provides the first potentially species-specific coproantigen test for human T. solium taeniasis.

  4. Elisa Alicia Lynch: a Dama de Aço do Paraguai * Elisa Alicia Lynch: the Steel ‘S Lady of Paraguay

    OpenAIRE

    Frota, Luciara Silveira de Aragão e

    2015-01-01

    Este trabalho mostra uma nova visão da irlandesa Elisa Alicia Lynch, longe da figura de prostituta manipuladora que incitou o Marechal Solano López no começo da Guerra do Paraguai. Dentro de uma corrente revisionista histórica, apoiada em Marc Bloch, propõe uma nova análise de seu papel na vida de Solano López e do Paraguai, comentando a literatura sobre o assunto.

  5. Applicability of Commercially Available ELISA Kits for the Quantification of Faecal Immunoreactive Corticosterone Metabolites in Mice

    DEFF Research Database (Denmark)

    Abelson, Klas S P; Kalliokoski, Otto; Teilmann, Anne Charlotte

    2016-01-01

    Background: Commercially available ELISA kits are popular among investigators that quantify faecal corticosterone or cortisol metabolites (FCM) for stress assessment in animals. However, in faeces, these assays mainly detect immunoreactive glucocorticoid metabolites. Since different assays contain......: The present study was designed to investigate corticosterone (CORT) in serum and FCM levels in faeces of laboratory mice, as quantified in four different ELISA kits (DRG EIA-4164, Demeditec DEV9922, Enzo ADI-900-097 and Cayman EIA kit 500655). Assay kits were chosen based on the origin of the antibody...... assays, in both groups of mice. In faecal samples, there was no consistent positive correlation between the levels detected in the four assays and the measured concentration of FCM also differed between assays. Conclusion: Whereas commercially available CORT ELISAs are frequently successfully used...

  6. Determination of PCBs in fish using enzyme-linked immunosorbent assay (ELISA)

    Science.gov (United States)

    Lasrado, J.A.; Santerre, C.R.; Zajicek, J.L.; Stahl, J.R.; Tillitt, D.E.; Deardorff, D.

    2003-01-01

    Polychlorinated biphenyls (PCBs) were determined in fish tissue using an enzyme-linked immunosorbent assay (ELISA). Standard curves for Aroclor 1248, 1254, and 1260 in catfish tissue were developed with ranges from 0.05 to 0.5 ppm and 0.5 to 5.0 ppm. Wild fish were initially analyzed using gas chromatography/electron-capture detection (GC/ECD) and those having residues within the standard curve ranges were analyzed with ELISA. Results obtained using ELISA and GC/ECD were not significantly different (p < 0.05) from 0.05 to 0.5 ppm. From 0.5 to 5.0 ppm, the standard curve for Aroclor 1254 was the best predictor of total PCB in wild fish samples.

  7. Evaluation of commercial ELISA kits for detection of antibodies against bovine atypical pestivirus

    DEFF Research Database (Denmark)

    Larska, Magdalena; Polak, Mirosław P.; Uttenthal, Åse

    A group of emerging bovine pestiviruses becomes a possible threat to Bovine Viral diarrhea virus (BVDV) control and eradication programs in the countries of their origin and in the new continents due to the lack of validated detection methods. The use of ELISA kits may be acheaper, time saving...... and less laborious option allowing screening for antibodies in large populations. Since test specific for emerging and new BVDV strains are still under preparation, the purpose of this work was to evaluate available BVDV antibody ELISA assays for their ability to detect antibodies against Hobi-like viruses....... Analysis of a panel of sera obtained from calves experimentally inoculated with Hobi-like virus (isolated from a calf from Thailand) and BVDV type 1 strain using five different ELISA kits in comparison to neutralization test was performed. The specificity and sensitivity of the tests depended greatly...

  8. Follow-up of neurocysticercosis patients after treatment using an antigen detection ELISA

    Directory of Open Access Journals (Sweden)

    Nguekam

    2003-03-01

    Full Text Available Seven patients with active neurocysticercosis (NCC received an eight days treatment with albendazole and were followed up using computed tomography (CT-scan and a monoclonal antibody based ELISA for the detection of circulating antigen (Ag-ELISA. Only three patients were cured as was shown by CT-scan and by the disappearance of circulating antigens one month after treatment. After a second course of albendazole therapy, two other patients became seronegative. CT-scan showed the disappearance of viable cysts in all persons who became seronegative whereas patients who were not cured remained seropositive. These preliminary results show that this Ag-ELISA is a promising technique for monitoring the success of treatment of NCC patients because of the excellent correlation between the presence of circulating antigens and of viable brain cysts.

  9. Field trial of a brucellosis competitive enzyme linked immunoabsorbent assay (ELISA)

    International Nuclear Information System (INIS)

    Samartino, L.E.; Gregoret, R.J.; Sigal, G.

    1998-01-01

    The purpose of this study was to evaluate the performance of a competitive ELISA system for the diagnosis of bovine brucellosis in comparison to conventional aerological tests routinely used in Argentina. A total of 2.500 serum samples, comprising Brucella-free herds, vaccinated cattle and naturally infected animals, was tested by the following tests: buffered plate agglutination, Rose Bengal, 2-mercaptoethanol, complement fixation, and indirect and competitive ELISAs. Specificity and relative sensitivity at each test were determined. The competitive ELISA was considered suitable for detection of vaccinated animals and had higher specificity than the other tests. The results point to the potential use of the test as a complementary assay in the brucellosis control programme in Argentina. (author)

  10. Performance of microscopy and ELISA for diagnosing Giardia duodenalis infection in different pediatric groups.

    Science.gov (United States)

    Silva, Renata K N R; Pacheco, Flávia T F; Martins, Adson S; Menezes, Joelma F; Costa-Ribeiro, Hugo; Ribeiro, Tereza C M; Mattos, Ângela P; Oliveira, Ricardo R; Soares, Neci M; Teixeira, Márcia C A

    2016-12-01

    Techniques for Giardia diagnosis based on microscopy are usually applied as routine laboratory testing; however, they typically exhibit low sensitivity. This study aimed to evaluate Giardia duodenalis and other intestinal parasitic infections in different pediatric groups, with an emphasis on the comparison of Giardia diagnostic techniques. Feces from 824 children from different groups (diarrheic, malnourished, with cancer and from day care) were examined by microscopy and ELISA for Giardia, Cryptosporidium sp. and Entamoeba histolytica coproantigen detection. Giardia-positive samples from day-care children, identified by either microscopy or ELISA, were further tested by PCR targeting of the β-giardin and Gdh genes. Statistically significant differences (Psp. in diarrheic and malnourished groups; infections by Entamoeba histolytica were found only in children with diarrhea. Considering positivity for Giardia by at least one method, ELISA was found to be more sensitive than microscopy (97% versus 55%). To examine discrepancies among the diagnostic methods, 71 Giardia-positive stool samples from day-care children were tested by PCR; of these, DNA was amplified from 51 samples (77.4%). Concordance of positivity between microscopy and ELISA was found for 48 samples, with 43 confirmed by PCR. Parasite DNA was amplified from eleven of the 20 Giardia samples (55%) identified only by ELISA. This study shows the higher sensitivity of ELISA over microscopy for Giardia diagnosis when a single sample is analyzed and emphasizes the need for methods based on coproantigen detection to identify this parasite in diarrheic fecal samples. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. Evaluation of dengue NS1 antigen rapid tests and ELISA kits using clinical samples.

    Directory of Open Access Journals (Sweden)

    Subhamoy Pal

    Full Text Available Early diagnosis of dengue virus (DENV infection can improve clinical outcomes by ensuring close follow-up, initiating appropriate supportive therapies and raising awareness to the potential of hemorrhage or shock. Non-structural glycoprotein-1 (NS1 has proven to be a useful biomarker for early diagnosis of dengue. A number of rapid diagnostic tests (RDTs and enzyme-linked immunosorbent assays (ELISAs targeting NS1 antigen (Ag are now commercially available. Here we evaluated these tests using a well-characterized panel of clinical samples to determine their effectiveness for early diagnosis.Retrospective samples from South America were used to evaluate the following tests: (i "Dengue NS1 Ag STRIP" and (ii "Platelia Dengue NS1 Ag ELISA" (Bio-Rad, France, (iii "Dengue NS1 Detect Rapid Test (1st Generation" and (iv "DENV Detect NS1 ELISA" (InBios International, United States, (v "Panbio Dengue Early Rapid (1st generation" (vi "Panbio Dengue Early ELISA (2nd generation" and (vii "SD Bioline Dengue NS1 Ag Rapid Test" (Alere, United States. Overall, the sensitivity of the RDTs ranged from 71.9%-79.1% while the sensitivity of the ELISAs varied between 85.6-95.9%, using virus isolation as the reference method. Most tests had lower sensitivity for DENV-4 relative to the other three serotypes, were less sensitive in detecting secondary infections, and appeared to be most sensitive on Day 3-4 post symptom onset. The specificity of all evaluated tests ranged from 95%-100%.ELISAs had greater overall sensitivity than RDTs. In conjunction with other parameters, the performance data can help determine which dengue diagnostics should be used during the first few days of illness, when the patients are most likely to present to a clinic seeking care.

  12. Development of a sandwich ELISA for the thrombin light chain identified by serum proteome analysis

    Directory of Open Access Journals (Sweden)

    Kazuyuki Sogawa

    2017-08-01

    Full Text Available We previously identified novel biomarker candidates in biliary tract cancer (BTC using serum proteome analysis. Among several candidates, we focused on thrombin light chain which is a 4204 Da peptide as the most promising biomarker for BTC. To move thrombin light chain toward potential diagnostic use, we developed an enzyme immunoassay that enables to measure serum thrombin light chain levels.Both one monoclonal antibody specific to the N-termini and one polyclonal antibody were used to develop a sandwich ELISA for thrombin light chain. The assay was evaluated by comparing the results with those obtained by the ClinProt™ system. Serum samples were obtained from 20 patients with BTC, 20 patients with BBTDs and 20 HVs using the ClinProt™ system and ELISA.The results of the established ELISA showed a positive correlation with the findings by ClinProt™ system (slope=0.3386, intercept=34.901, r2=0.9641. The performance of the ELISA was satisfactory in terms of recovery (97.9–102.5% and within-run (1.5–4.8% and between-day (1.9–6.7% reproducibility. Serum thrombin light chain levels were significantly greater in BTC (176.5±47.2 ng/mL than in BBTDs (128.6±17.4 ng/mL and HVs (127.6±16.0 ng/mL (p<0.001.The sandwich ELISA developed in this study will be useful for validation of the diagnostic significance of serum thrombin light chain levels in various cancers. Keywords: Thrombin light chain, Biliary tract cancer, Sandwich ELISA, Serum biomarker

  13. Antibody-nanoparticle conjugates to enhance the sensitivity of ELISA-based detection methods.

    Directory of Open Access Journals (Sweden)

    Margaret M Billingsley

    Full Text Available Accurate antigen detection is imperative for clinicians to diagnose disease, assess treatment success, and predict patient prognosis. The most common technique used for the detection of disease-associated biomarkers is the enzyme linked immunosorbent assay (ELISA. In an ELISA, primary antibodies are incubated with biological samples containing the biomarker of interest. Then, detectible secondary antibodies conjugated with horseradish peroxidase (HRP bind the primary antibodies. Upon addition of a color-changing substrate, the samples provide a colorimetric signal that directly correlates to the targeted biomarker concentration. While ELISAs are effective for analyzing samples with high biomarker content, they lack the sensitivity required to analyze samples with low antigen levels. We hypothesized that the sensitivity of ELISAs could be enhanced by replacing freely delivered primary antibodies with antibody-nanoparticle conjugates that provide excess binding sites for detectible secondary antibodies, ultimately leading to increased signal. Here, we investigated the use of nanoshells (NS decorated with antibodies specific to epidermal growth factor receptor (EGFR as a model system (EGFR-NS. We incubated one healthy and two breast cancer cell lines, each expressing different levels of EGFR, with EGFR-NS, untargeted NS, or unconjugated EGFR antibodies, as well as detectable secondary antibodies. We found that EGFR-NS consistently increased signal intensity relative to unconjugated EGFR antibodies, with a substantial 13-fold enhancement from cells expressing high levels of EGFR. Additionally, 40x more unconjugated antibodies were required to detect EGFR compared to those conjugated to NS. Our results demonstrate that antibody-nanoparticle conjugates lower the detection limit of traditional ELISAs and support further investigation of this strategy with other antibodies and nanoparticles. Owing to their enhanced sensitivity, we anticipate that

  14. Improved detection of canine Angiostrongylus vasorum infection using real-time PCR and indirect ELISA.

    Science.gov (United States)

    Jefferies, Ryan; Morgan, Eric R; Helm, Jenny; Robinson, Matthew; Shaw, Susan E

    2011-12-01

    This study reports the development of a real-time PCR assay and an indirect ELISA to improve on current detection of canine Angiostrongylus vasorum infection. A highly specific fluorescent probe-based, real-time PCR assay was developed to target the A. vasorum second internal transcribed spacer region and detected DNA in EDTA blood, lung tissue, broncho-alveolar larvage fluid, endotracheal mucus, pharyngeal swabs and faecal samples. PCR was fast (∼1 h), highly efficient when using EDTA blood samples, consistently detected a single molecule of parasite DNA and did not amplify DNA from other parasitic nematodes or definitive host species. An indirect ELISA was also developed using the soluble protein fraction from adult A. vasorum worms. Some cross-reactive antigen recognition was observed when tested against sera from dogs infected with Crenosoma vulpis (n = 8), Toxocara canis (n = 5) and Dirofilaria immitis (n = 5). This was largely overcome by setting the cut-off for a positive result at an appropriately high level. Field evaluation of the real-time PCR and ELISA was conducted by testing sera and EDTA blood from dogs with suspected A. vasorum infection (n = 148) and compared with the Baermann's larval migration test in faeces. Thirty-one dogs were positive by at least one test. Of these, 20 (65%) were detected by the Baermann method, 18 (58%) by blood PCR, 24 (77%) by ELISA and 28 (90%) by blood PCR and ELISA together. Combined testing using real-time PCR and ELISA therefore improved the detection rate of A. vasorum infection and holds promise for improved clinical diagnosis and epidemiological investigation.

  15. Validation and use of an ELISA kit for the diagnosis of Babesia bovis in Cuba

    International Nuclear Information System (INIS)

    Blandino, T.; Alonso, M.; Barrera, M.; Mendoza, E.

    1998-01-01

    Babesia bovis, the most important etiological agent causing bovine babesiosis, is widely distributed in Cuba and affects mainly adult cattle. A survey of the prevalence of the disease in cattle using an ELISA kit (FAO/IAEA) revealed that 34.2% of the animals between 6 and 18 months of age were positive to Babesia bovis, whereas 69.9% on the cattle older than 18 months were positive. Antibodies to Babesia bovis were detected in 96.9% of calves vaccinated with an attenuated Babesia bovis vaccine. A good correlation was found between the results of ELISA kit with those from indirect immunofluorescence and immunoperoxidase tests developed in Cuba. (author)

  16. Evaluation of a serological Salmonella Mix-ELISA for poultry used in a national surveillance programme

    DEFF Research Database (Denmark)

    Feld, Niels Christian; Ekeroth, Lars; Gradel, K.O.

    2000-01-01

    by Mix-ELISA and by faecal culture, and in case of a positive result in either of these a repeated, serological testing was performed, and 60 animals were organ-cultured. If one of these samplings was positive, the flock was declared salmonella infected. In a period of 3 months, 35 flocks were found......A Mix-ELISA using lipopolysaccharide antigens from Salmonella enterica serotype Enteritidis and Typhimurium? was evaluated using samples collected over time in the Danish salmonella surveillance programme for poultry. Serological samples (n = 42813) taken from broiler-breeder flocks after a year...

  17. Glove powder's carrying capacity for latex protein: analysis using the ASTM ELISA test.

    Science.gov (United States)

    Beezhold, D; Horton, K; Hickey, V; Daddona, J; Kostyal, D

    2003-01-01

    Glove donning powders carry latex proteins and disperse them into the workplace environment. We have used the ASTM D6499 ELISA to quantify the amount of latex antigen bound to and carried by glove powders. We could differentiate between a small amount of protein actually bound to the powders and a larger amount carried by the powder. Enhanced binding of a major allergen, Hev b 5, to the starch powders was demonstrated by Western blot. The D6499 ELISA is able to measure total latex antigen, soluble and powder bound, simultaneously without the need to centrifuge the samples.

  18. Replacement of Antibodies in Pseudo-ELISAs: Molecularly Imprinted Nanoparticles for Vancomycin Detection.

    Science.gov (United States)

    Canfarotta, Francesco; Smolinska-Kempisty, Katarzyna; Piletsky, Sergey

    2017-01-01

    The enzyme-linked immunosorbent assay (ELISA) is a widely employed analytical test used to quantify a given molecule. It relies on the use of specific antibodies, linked to an enzyme, to target the desired molecule. The reaction between the enzyme and its substrate gives rise to the analytical signal that can be quantified. Thanks to their robustness and low cost, molecularly imprinted polymer nanoparticles (nanoMIPs) are a viable alternative to antibodies. Herein, we describe the synthesis of nanoMIPs imprinted for vancomycin and their subsequent application in an ELISA-like format for direct replacement of antibodies.

  19. Protein unfolding allows use of commercial antibodies in an apolipoprotein M sandwich ELISA

    DEFF Research Database (Denmark)

    Bosteen, Markus Høybye; Dahlbäck, Björn; Nielsen, Lars Bo

    2015-01-01

    that specifically recognizes human apoM in plasma using commercially available reagents. Commercial apoM antibodies were screened for compatibility in a sandwich ELISA-based assay. One optimal pair of antibodies was chosen, and sample preparation, buffers, and incubation times were optimized to generate a simple...... and reproducible method. Validation and comparison to a previously described ELISA for apoM confirmed that the assay displays a high degree of sensitivity, specificity, and precision. Our results show that commercially available antibodies can be used to accurately measure human plasma apoM. This method can...

  20. New technology for regiospecific covalent coupling of polysaccharide antigens in ELISA for serological detection

    DEFF Research Database (Denmark)

    Jauho, E.S.; Boas, Ulrik; Wiuff, Camilla

    2000-01-01

    In this study we demonstrate a new UV irradiation technique for covalent coupling of bacterial polysaccharides derived from lipopolysaccharides to microtiter plates and the use of such plates in an enzyme linked immunosorbent assay (ELISA). Lipopolysaccharides were cleaved by mild acid hydrolysis...... describe the use of this technique for the immobilization of Lipopolysaccharide derived polysaccharides from Salmonella Typhimurium and Salmonella Choleraesuis lipopolysaccharides, representing the O-antigens 1, 4, 5, 6, 7, and 12, The functional polysaccharide surface gave similar ELISA results to plates...

  1. Microcapillary blood sampling for serological examinations by radioimmunoassay (RIA) and enzyme immunoassay (ELISA)

    Energy Technology Data Exchange (ETDEWEB)

    Rodak, L; Smid, B; Valicek, L; Jurak, E [Vyzkumny Ustav Veterinarniho Lekarstvi, Brno-Medlanky (Czechoslovakia)

    1984-01-01

    Methods were tested of sampling blood and blood serum for serological examinations on filtration paper and into heparinized glass capillaries with transfer into the dilution solution of the given composition. Samples were also examined for ACH virus antibodies. The suitability of the sampling was verified by an examination of samples using ELISA and RIA methods. The results showed the suitability of sampling using microcapillaries. The titres of virus antibodies found using the ELISA and RIA methods were identical and the sensitivity of antibody detection was not reduced even after the sample had been stored for 60 days at a temperature of 20 degC.

  2. Comparison of radioimmunoassay and ELISA methods for detection of antibodies to chromatin components

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, E; Cheng, N [North Carolina Univ., Chapel Hill (USA). Dept. of Bacteriology and Immunology

    1983-09-16

    A solid phase radioimmunoassay has been compared with an enzyme-linked immunosorbent assay (ELISA) for efficacy in measuring anti-chromatin antibodies. The low backgrounds achieved with the radioimmunoassay method produced a high signal-to-noise ratio and enabled detection of the human test antiserum at a dilution of 1:102,400. By contrast, the ELISA could detect the same antiserum only at a dilution of 1;3200 and above. The radioimmunoassay was consistently more sensitive than the ELSIA for detection of anti-chromatin antibodies in a number of human and mouse sera and ascites fluid containing a monoclonal antibody. Factors affecting sensitivity in both assays are discussed.

  3. Diogenite-like Features in the Spitzer IRS (5-35 micrometers) Spectrum of 956 ELISA

    Science.gov (United States)

    Lim, Lucy F.; Emery, Joshua P.; Moskovitz, Nicholas A.

    2009-01-01

    We report preliminary results from the Spitzer Infrared Spectrograph (IRS) observations of the V-type asteroid 956 Elisa. Elisa was observed as part of a campaign to measure the 5.2-38 micron spectra of small basaltic asteroids with the Spitzer IRS. Targets include members of the dynamical family of the unique large differentiated asteroid 4 Vesta ("Vesroids"), several outer-main-belt basaltic asteroids whose orbits exclude them from originating on 4 Vesta, and the basaltic near-Earth asteroid 4055 Magellan.

  4. Validation of the ELISA technique for diagnosis of trypanosomiasis in cattle in Uganda

    International Nuclear Information System (INIS)

    Okuna, N.M.

    1992-01-01

    ELISA, developed in ILRAD for diagnosis of T. congolense, T. brucei and T. vivax in cattle, has not been validated in Uganda. This study was undertaken to validate the technique. Negative reference sera were collected from 44 cattle in Kapchorwa, a tsetse-free area. The cattle were free of the three trypanosome species T. congolense, T. brucei and T. vivax by the haematocrit buffy coat technique (BCT). But by ELISA, three were positive for T. vivax, one for both T. congolense and T. vivax and one for T. congolense. Sera were collected from the same 44 cattle 10 weeks later. The cattle were again free of T. congolense, T. brucei and T. vivax, both by BCT and by mouse inoculations. Two cattle out of 450 screened at a centre 5 km away had T. vivax by BCT. The ELISA results for the second set of sera were quite similar to the results obtained from the first set of sera. The calculated optical density (D) cut off point was 50 for both T. brucei and T. vivax, but it was 60 for T. congolense. Sera from 5 cattle which had T. theileri and two which had microfilaria were all negative for antigenaemia by ELISA. Positive reference sera were collected form 40 cattle in a high tsetse challenge area. Using the haematocrit buffy coat technique, 5 had T. vivax, two had T. brucei and one had T. congolense. Checked by ELISA for antigenaemia, only 4 cattle were free of all the three trypanosome species, T. congolense, T. vivax and T. brucei. All the 40 cattle were treated with Diminazene aceturate at the rate of 7 mg/kg body weight. Two weeks later, the ELISA test showed that 10 cattle were free of any antigenaemia. Those still positive for antigenaemia had lower OD readings. The ELISA technique is valid. It is much more sensitive compared to parasitological tests. It is specific since none of the 7 cattle with either T. theileri or microfilaria gave positive results by ELISA. The technique would be very useful for epizootiological studies. (author)

  5. Acoustic waves and the detectability of first-order phase transitions by eLISA

    Science.gov (United States)

    Weir, David J.

    2017-05-01

    In various extensions of the Standard Model it is possible that the electroweak phase transition was first order. This would have been a violent process, involving the formation of bubbles and associated shock waves. Not only would the collision of these bubbles and shock waves be a detectable source of gravitational waves, but persistent acoustic waves could enhance the signal and improve prospects of detection by eLISA. I summarise the results of a recent campaign to model such a phase transition based on large-scale hydrodynamical simulations, and its implications for the eLISA mission.

  6. European Union funded project on the development of a whole complement deficiency screening ELISA

    DEFF Research Database (Denmark)

    Würzner, Reinhard; Tedesco, Francesco; Garred, Peter

    2015-01-01

    A whole complement ELISA-based assay kit, primarily designed to screen for deficiencies in components of the complement system was developed during a European Union grant involving more than a dozen European scientists and a small-medium enterprise company (Wieslab, which later merged into Eurodi......A whole complement ELISA-based assay kit, primarily designed to screen for deficiencies in components of the complement system was developed during a European Union grant involving more than a dozen European scientists and a small-medium enterprise company (Wieslab, which later merged...

  7. Capture ELISA for IgM antibodies against Plasmodium falciparum glutamate rich protein

    DEFF Research Database (Denmark)

    Dziegiel, M; Borre, Mette; Petersen, E

    1992-01-01

    This report describes a novel mu chain capture ELISA for the detection of IgM antibodies against a Plasmodium falciparum antigen. A fragment of the 220 kDa P. falciparum glutamate rich protein containing amino acid residues 489-1271 was expressed in E. coli as a recombinant chimeric beta-galactos......This report describes a novel mu chain capture ELISA for the detection of IgM antibodies against a Plasmodium falciparum antigen. A fragment of the 220 kDa P. falciparum glutamate rich protein containing amino acid residues 489-1271 was expressed in E. coli as a recombinant chimeric beta...

  8. eLISA eccentricity measurements as tracers of binary black hole formation

    OpenAIRE

    Nishizawa, Atsushi; Berti, Emanuele; Klein, Antoine; Sesana, Alberto

    2016-01-01

    Up to hundreds of black hole binaries individually resolvable by eLISA will coalesce in the Advanced LIGO/Virgo band within ten years, allowing for multi-band gravitational wave observations. Binaries formed via dynamical interactions in dense star clusters are expected to have eccentricities $e_0\\sim 10^{-3}$-$10^{-1}$ at the frequencies $f_0=10^{-2}$ Hz where eLISA is most sensitive, while binaries formed in the field should have negligible eccentricity in both frequency bands. We estimate ...

  9. Microcapillary blood sampling for serological examinations by radioimmunoassay (RIA) and enzyme immunoassay (ELISA)

    International Nuclear Information System (INIS)

    Rodak, L.; Smid, B.; Valicek, L.; Jurak, E.

    1984-01-01

    Methods were tested of sampling blood and blood serum for serological examinations on filtration paper and into heparinized glass capillaries with transfer into the dilution solution of the given composition. Samples were also examined for ACH virus antibodies. The suitability of the sampling was verified by an examination of samples usiOg ELISA and RIA methods. The results showed the suitability of sampling using microcapillaries. The titres of virus antibodies found using the ELISA and RIA methods were identical and the sensitivity of antibody detection was not reduced even after the sample had been stored for 60 days at a temperature of 20 degC. (B.S.)

  10. Evaluation of a blocking ELISA for screening of antibodies against porcine reproductive and respiratory syndrome (PRRS) virus

    DEFF Research Database (Denmark)

    Sørensen, K.J.; Bøtner, Anette; Madsen, E.S.

    1997-01-01

    A blocking Elisa was developed for the detection of antibodies against PRRS virus with a view to satisfying the need for examination of blood samples on a large scale. The test was evaluated in comparison with an indirect Elisa and the immunoperoxidase monolayer assay. The blocking Elisa...... was sensitive and specific. It had a higher capacity and was cheaper to perform than the immunoperoxidase monolayer assay and the indirect Elisa. It was comparable to the immunoperoxidase monolayer assay and better than the indirect Elisa in detecting antibodies formed early after infection, and it was superior...... to both the immunoperoxidase monolayer assay and the indirect Elisa in detecting antibodies at a late stage of infection....

  11. A comparative study of an elisa test and an indirect immunofluorescence test for serological diagnosis of Babesia bovis infection

    International Nuclear Information System (INIS)

    Martins, J.R.; Cheong, F.H.; Correa, B.L.; Radley, D.E.; Cereser, V.H.

    1998-01-01

    Detection of antibodies to Babesia bovis in cattle is essential for the understanding of the epidemiology of babesiosis and this study was concerned with comparing the indirect fluorescent antibody with the ELISA. Both assays gave rise to 100% sensitivity whilst the ELISA was shown to be marginally more specific at 98%. The ease of use and low cost of the ELISA would make it the more obvious choice in conducting future serological surveys for this parasite. (author)

  12. Application of the antigen ELISA for monitoring the effectiveness of the tsetse and trypanosomosis control campaign in Zambia

    Energy Technology Data Exchange (ETDEWEB)

    Sinyangwe, L N; Munyama, G M; Mubanga, J [Central Veterinary Research Inst. (CVRI), Lusaka (Zambia)

    1997-02-01

    Antibody and antigen-detection ELISA were used to screen sera originating from a tsetse free area. In addition, bovine samples from tsetse infested areas were analysed using the Buffy Coat Technique (BCT) and the antigen ELISA. Few samples from a negative control population were detected positive resulting in a very good specificity for both tests. When screening a trypanosome infected population the BCT detected more acute and the Ag-ELISA more chronic infections. In conclusion, the antigen ELISA should be used in combination with the BCT, especially in geographical areas where the BCT does not detect any patent infections. (author). 2 refs, 4 figs, 4 tabs.

  13. Application of the antigen ELISA for monitoring the effectiveness of the tsetse and trypanosomosis control campaign in Zambia

    International Nuclear Information System (INIS)

    Sinyangwe, L.N.; Munyama, G.M.; Mubanga, J.

    1997-01-01

    Antibody and antigen-detection ELISA were used to screen sera originating from a tsetse free area. In addition, bovine samples from tsetse infested areas were analysed using the Buffy Coat Technique (BCT) and the antigen ELISA. Few samples from a negative control population were detected positive resulting in a very good specificity for both tests. When screening a trypanosome infected population the BCT detected more acute and the Ag-ELISA more chronic infections. In conclusion, the antigen ELISA should be used in combination with the BCT, especially in geographical areas where the BCT does not detect any patent infections. (author). 2 refs, 4 figs, 4 tabs

  14. Development of a blocking ELISA for detection of Mycoplasma hyopneumoniae infection based on a monoclonal antibody against protein P65.

    Science.gov (United States)

    Liu, Maojun; DU, Gaimei; Zhang, Yue; Wu, Yuzi; Wang, Haiyan; Li, Bin; Bai, Yun; Feng, Zhixin; Xiong, Qiyan; Bai, Fangfang; Browning, Glenn F; Shao, Guoqing

    2016-09-01

    Mycoplasma hyopneumoniae causes porcine enzootic pneumonia, an economically important disease of swine. A more sensitive and reliable method for detection of serum antibodies is needed for epidemiological investigations and to evaluate the effect of immunization. We expressed the M. hyopneumoniae protein P65 in Escherichia coli and produced a monoclonal antibody (mAb) that bound specifically to recombinant P65. Using this mAb, a blocking enzyme linked immunosorbent assay (ELISA) was developed. The blocking ELISA had similar specificity to and sensitivity with the commercial ELISA produced by IDEXX. Thus, this blocking ELISA is a useful test for serological confirmation of M. hyopneumoniae infection.

  15. Agricultural production - Phase 2. Indonesia. Implementation of ELISA for brucellosis at DGLS laboratories in indonesia

    International Nuclear Information System (INIS)

    Patten, B.

    1992-01-01

    This expert mission was performed to assess the current status of activities relating to brucellosis testing at the Regional Disease Investigation Centres of the Directorate General of Livestock Services in Indonesia, and to assist in the establishment and validation of the ELISA technique for detecting Brucella antibodies

  16. Development of hen antihepatitis B antigen IgY-based conjugate for ELISA assay

    Directory of Open Access Journals (Sweden)

    Najat Muayed Nafea

    2015-01-01

    Conclusions: This study showed that laying hens can be used as an alternative source for production of polyclonal antibodies against HBsAg and anti-HBs IgY could be labeled with HRP enzyme and could subsequently be used successfully as secondary antibody in ELISA for detection of HBsAg in the patients sera.

  17. Measuring BDNF in saliva using commercial ELISA : Results from a small pilot study

    NARCIS (Netherlands)

    Vrijen, Charlotte; Schenk, Hendrika M.; Hartman, Catharina A.; Oldehinkel, Albertine J.

    Brain-derived neurotrophic factor (BDNF) is a protein often studied in psychiatric populations. Commercial ELISA kits have been validated for measuring BDNF in blood plasma and serum, but blood collection is an invasive method which cannot always be used. The aim of this pilot study was to explore

  18. Comparison of four HTLV-I and HTLV-I + II ELISAs

    NARCIS (Netherlands)

    Vrielink, H.; Reesink, H.; Habibuw, M.; Schuller, M.; van der Meer, C.; Lelie, P.

    1999-01-01

    BACKGROUND: Various countries require blood donor screening using assays applying specific HTLV-I and HTLV-II antigens. We evaluated the sensitivity and specificity of 4 anti-HTLV-I + II ELISAs (Abbott, Murex, Organon Teknika and Ortho). METHODS: Panel A consisted of HTLV-I-positive individuals (n =

  19. A Direct, Competitive Enzyme-Linked Immunosorbent Assay (ELISA) as a Quantitative Technique for Small Molecules

    Science.gov (United States)

    Powers, Jennifer L.; Rippe, Karen Duda; Imarhia, Kelly; Swift, Aileen; Scholten, Melanie; Islam, Naina

    2012-01-01

    ELISA (enzyme-linked immunosorbent assay) is a widely used technique with applications in disease diagnosis, detection of contaminated foods, and screening for drugs of abuse or environmental contaminants. However, published protocols with a focus on quantitative detection of small molecules designed for teaching laboratories are limited. A…

  20. Evaluation of ethanol vortex ELISA for detection of bovine tuberculosis in cattle and deer

    Science.gov (United States)

    Background The use of serological assays for diagnosis of bovine tuberculosis (TB) has been intensively studied and use of specific antigens have aided in improving the diagnostic accuracy of the assays. In the present study, we report an in-house enzyme linked immunosorbent assay (ELISA), developed...

  1. An ELISA-inhibition test using monoclonal antibody for the serology of leprosy

    NARCIS (Netherlands)

    Klatser, P. R.; de Wit, M. Y.; Kolk, A. H.

    1985-01-01

    In this study a mouse monoclonal antibody (47-9) is described, which recognized an epitope on the 36 kD protein antigen of M. leprae. The monoclonal antibody showed specificity for M. leprae. An ELISA-inhibition test based on the competitive inhibition by antibodies from human test sera of the

  2. Rapid Detection of Food Allergens by Microfluidics ELISA-Based Optical Sensor

    Directory of Open Access Journals (Sweden)

    Xuan Weng

    2016-06-01

    Full Text Available The risks associated with the presence of hidden allergens in food have increased the need for rapid, sensitive, and reliable methods for tracing food allergens in commodities. Conventional enzyme immunosorbent assay (ELISA has usually been performed in a centralized lab, requiring considerable time and sample/reagent consumption and expensive detection instruments. In this study, a microfluidic ELISA platform combined with a custom-designed optical sensor was developed for the quantitative analysis of the proteins wheat gluten and Ara h 1. The developed microfluidic ELISA biosensor reduced the total assay time from hours (up to 3.5 h to 15–20 min and decreased sample/reagent consumption to 5–10 μL, compared to a few hundred microliters in commercial ELISA kits, with superior sensitivity. The quantitative capability of the presented biosensor is a distinctive advantage over the commercially available rapid methods such as lateral flow devices (LFD and dipstick tests. The developed microfluidic biosensor demonstrates the potential for sensitive and less-expensive on-site determination for rapidly detecting food allergens in a complex sample system.

  3. A monoclonal antibody to inclusion body disease of cranes virus enabling specific immunohistochemistry and competitive ELISA

    Science.gov (United States)

    Letchworth, G.J.; Fishel, J.R.; Hansen, W.R.

    1997-01-01

    Inclusion body disease of cranes (IBDC) herpesvirus kills some infected cranes and persists in convalescent animals. To enable further study and rapid identification of carrier animals, we developed a monoclonal antibody (MAb) to IBDC virus and used it in immunohistochemistry and a competitive enzyme-linked immunosorbent assay (ELISA). We used conventional techniques to make murine MAbs directed against IBDC virus purified from infected duck embryo cells. Hybridomas reacting in an ELISA with IBDC virus but not uninfected duck embryo cells were characterized by radioimmunoprecipitation, in situ immunohistochemistry, and competitive ELISA with neutralizing and nonneutralizing crane sera. MAb 2C11 immunoprecipitated 59-, 61-, and 110-kD proteins from IBDC virus-infected but not uninfected cells and stained glutaraldehyde-fixed IBDC virus plaques but not surrounding uninfected duck embryo cells in vitro. Antibody 2C11 did not react with duck embryo cells infected with falcon herpesvirus, psittacine herpesvirus, infectious laryngotracheitis, pigeon herpesvirus, or duck plague virus. A competitive ELISA using antibody 2C11 identified most sera that were positive in the neutralization test. This antibody will be useful in further characterizing IBDC virus, its pathogenesis, and its natural history.

  4. Evaluation of an indirect ELISA for the diagnosis of Babesia bovis in Uruguay

    International Nuclear Information System (INIS)

    Cardozo, H.; Solari, M.A.; Etchebarne, J.

    1992-01-01

    In initially establishing the FAO/IAEA indirect ELISA for the detection of antibodies to Babesia bovis, the optical density (OD) values of sera from known positive or negative local cattle were compared to the OD values obtained from the negative and positive reference sera provided with the ELISA kit. The percentage of false positive and negative sera were 2.53% and 2.97% respectively. The cut-off values for the negative reference serum in the kit were compared with those of a local negative population. These values were found to be similar. The specificity of the test was evaluated by testing 30 sera from animals experimentally infected with Anaplasma marginale and 30 sera from animals infected with Babesia bigemina. These were no cross-reaction either between A. marginale and B. bovis or between B. bigemina and B. bovis. A serological survey using this ELISA kit was carried out on animals from an enzootic area and an area free from the vecot Boophilus microplus. 53 out of 282 animals (18.8%) in the enzootic area were positive whilst all the animals (113) from the free area were negative. This study would indicate that the FAO/IAEA ELISA kit has a sensitivity of around 98% and specificity of 97%. (author). 8 refs, 2 figs, 2 tabs

  5. Correlation between ELISA and ML Flow assays applied to 60 Brazilian patients affected by leprosy

    NARCIS (Netherlands)

    Da Silva, Rozana C.; Lyon, Sandra; Lyon, Ana C.; Grossi, Maria A. F.; Lyon, Silvia H.; Bührer-Sékula, Samira; Antunes, Carlos M. F.

    2010-01-01

    Serological tests can be helpful in classifying leprosy patients as having either the paucibacillary or the multibacillary form. The aim of this study was to evaluate the concordance between two serological assays, i.e. ML Flow and ELISA, in a population of leprosy patients in Brazil. The

  6. Evaluation of ELISA tests specific for Shiga toxin 1 and 2 in food and water samples

    Science.gov (United States)

    Two enzyme-linked immunosorbent assay (ELISA) kits were evaluated for their effectiveness in detecting and differentiating between Shiga toxin 1 and 2 (Stx1 and Stx2) produced by Shiga toxin-producing E. coli (STEC) inoculated into food and water samples. Each kit incorporated monoclonal antibodies ...

  7. Establishment of a quantitative ELISA capable of determining peptide - MHC class I interaction

    DEFF Research Database (Denmark)

    Sylvester-Hvid, C; Kristensen, N; Blicher, T

    2002-01-01

    dependent manner. Here, we exploit the availability of these molecules to generate a quantitative ELISA-based assay capable of measuring the affinity of the interaction between peptide and MHC-I. This assay is simple and sensitive, and one can easily envisage that the necessary reagents, standards...

  8. Agricultural production - Phase 2. Indonesia. National training course on ELISA for seradiagnosis of animal diseases (5)

    International Nuclear Information System (INIS)

    Jacobson, R.H.

    1992-01-01

    This report describes the content of a three-week national training course for 16 participants from regional Disease Investigation Centres and other agencies in Indonesia. The subject of the course was the use of ELISA for the diagnosis of animal diseases in Indonesia, with particular emphasis placed on bovine brucellosis

  9. Characterisation of an ELISA detecting immunoglobulin G to Mycobacterium avium subsp. paratuberculosis in bovine colostrum

    DEFF Research Database (Denmark)

    Zervens, Lisa Marie-Louise; Nielsen, Søren Saxmose; Jungersen, Gregers

    2013-01-01

    Although colostrum has been used to detect specific immunoglobulin (Ig) G to Mycobacterium avium subsp. paratuberculosis (MAP) in cattle, confounding, non-specific reactions can be a problem. The objectives of this study were to determine the proportion of non-specific ELISA reactions in samples...

  10. Validation of an indirect ELISA for the diagnosis of Babesia bovis in cattle in Yucatan, Mexico

    International Nuclear Information System (INIS)

    Dominguez, A.J.L.; Rodriguez, V.R.I.; Oura, C.; Cob, G.L.A.

    1998-01-01

    The ELISA kit provided by the FAO/IAEA for the diagnosis of Babesia bovis was validated. In order to determine the appropriate ELISA cut-off point that would serve as the threshold between positive and negative samples, 119 serum samples from a Mexican Babesia-free zone were analyzed. The optimal cut-off point chosen was at 12% of the reactivity of the high positive control serum sample (PP) which resulted in a specificity of 97%. One hundred and ninety-six cattle from Wisconsin, USA, were introduced into Yucatan, Mexico, of which 181 were vaccinated with an attenuated live Babesia bovis vaccine; 15 animals remained as unvaccinated controls. Before and after vaccination all animals were bled and tested by enzyme linked immunosorbent assay (ELISA) and indirect fluorescence antibody test (IFAT). Both tests showed a high degree of correlation in their results. To evaluate an immune response to vaccination the optimal cut-off point chosen was 12% PP resulting in a sensitivity 99% and a specificity 95%. We concluded that the ELISA test has proved to be useful in Yucatan, Mexico for serological surveys and monitoring the efficiency o vaccination programmes. (author)

  11. Combined use of random access and ELISA analyzers in the microbiological serology laboratory

    Directory of Open Access Journals (Sweden)

    Alessandra Moroni

    2008-09-01

    Full Text Available In the last years the trend of centralizing small laboratories in large reference centers led to a careful evaluation of the diagnostic profiles. In the serology laboratory of Microbiology Unit, St. Orsola-Malpighi Hospital, Bologna, Italy the choice has been to combine random access analyzers (ARCHITECT Abbott and ELISA analyzers (BEPIII Dade Behring.

  12. RT-PCR-ELISA as a tool for diagnosis of low-pathogenicity avian influenza

    DEFF Research Database (Denmark)

    Dybkaer, Karen; Munch, Mette; Handberg, Kurt Jensen

    2003-01-01

    A one-tube reverse transcriptase/polymerase chain reaction coupled with an enzyme-linked immunosorbent assay (RT-PCR-ELISA) was developed for the rapid detection of avian influenza virus (AIV) in clinical specimens. A total of 419 swab pools were analyzed from chickens experimentally infected...

  13. High sensitivity, high surface area Enzyme-linked Immunosorbent Assay (ELISA).

    Science.gov (United States)

    Singh, Harpal; Morita, Takahiro; Suzuki, Yuma; Shimojima, Masayuki; Le Van, An; Sugamata, Masami; Yang, Ming

    2015-01-01

    Enzyme-linked immunosorbent assays (ELISA) are considered the gold standard in the demonstration of various immunological reactions with an application in the detection of infectious diseases such as during outbreaks or in patient care. This study aimed to produce an ELISA-based diagnostic with an increased sensitivity of detection compared to the standard 96-well method in the immunologic diagnosis of infectious diseases. A '3DStack' was developed using readily available, low cost fabrication technologies namely nanoimprinting and press stamping with an increased surface area of 4 to 6 times more compared to 96-well plates. This was achieved by stacking multiple nanoimprinted polymer sheets. The flow of analytes between the sheets was enhanced by rotating the 3DStack and confirmed by Finite-Element (FE) simulation. An Immunoglobulin G (IgG) ELISA for the detection of antibodies in human serum raised against Rubella virus was performed for validation. An improved sensitivity of up to 1.9 folds higher was observed using the 3DStack compared to the standard method. The increased surface area of the 3DStack developed using nanoimprinting and press stamping technologies, and the flow pattern between sheets generated by rotating the 3DStack were potential contributors to a more sensitive ELISA-based diagnostic device.

  14. International ring trial to detect anti-Trichinella IgG by ELISA on pig sera.

    Science.gov (United States)

    In the present study, the sensitivity and specificity of the ELISA assay determined by the CRLP validation was 100% and 98.29%, respectively. The assay was reproducible, moreover, based on the receiver-operator characteristic (ROC) curve, the sensitivity and specificity of the assay reached 97.5% an...

  15. COMPARISONS OF ELISA AND WESTERN BLOT ASSAYS FOR DETECTION OF CRYPTOSPORIDIUM ANTIBODY

    Science.gov (United States)

    A seroprevalence survey was conducted using ELISA and Western blot (WB) assays for antibody to three Cryptosporidium antigens on 380 blood donors in Jackson County, Oregon. The purpose was to determine if either assay could detect serological evidence of an outbreak which occurre...

  16. DETERMINATION OF 3,5,6-TRICHLORO-2-PYRIDINOL (TCP) BY ELISA

    Science.gov (United States)

    A sensitive, competitive enzyme-linked immunosorbent assay (ELISA) for 3,5,6-trichloro-2pyridinol (TCP) has been developed to quantitate parts per billion (ppb) amounts of the analyte in urine. TCP is a major metabolite and environmental degradation product of the insecticide c...

  17. The impact of milk handling procedures on Ostertagia ostertagi antibody ELISA test results.

    Science.gov (United States)

    Vanderstichel, Raphaël; Dohoo, Ian; Stryhn, Henrik

    2010-04-19

    The impact of various milk handling stressors were analyzed using a commercially available enzyme-linked immunosorbent assay (ELISA) test measuring Ostertagia ostertagi antibodies in milk from dairy cattle (Svanovir). An indirect ELISA has the ability to determine the amount of milk production losses related to intestinal parasitism. The ELISA test recommends fresh defatted milk, however, milk collected from Dairy Herd Improvement (DHI) programs in North America undergo many stressors, including, heating, freezing and are not defatted. Normalized optical density ratios (ODRs) were compared between fresh defatted milk and milk subjected to one or more stressors with a linear mixed model accounting for differences in variation between the fresh and the frozen samples. Concordance correlation coefficients were also analyzed for comparisons to other similar studies. After accounting for random cow and container effects, the treatment factors interacted with each other (p<0.001). Biologically interesting contrasts were created to explain the interaction. The estimated difference in ODR between the milk samples handled according to recommendations of the manufacturers of Svanovir and the whole milk samples that were subjected to the most extreme treatment (heated, frozen, thawed, and re-frozen for 4 weeks) was 0.062 (p<0.001). This difference represented less than 5% of the range, and was thus considered biologically negligible. Frozen whole milk processed by DHI programs, the most likely method of collecting on-farm samples in North America, will likely yield reliable results for the indirect ELISA tests, particularly, Svanovir.

  18. A false positive food chain error associated with a generic predator gut content ELISA

    Science.gov (United States)

    Conventional prey-specific gut content ELISA and PCR assays are useful for identifying predators of insect pests in nature. However, these assays are prone to yielding certain types of food chain errors. For instance, it is possible that prey remains can pass through the food chain as the result of ...

  19. Ultrasensitive microfluidic solid-phase ELISA using an actuatable microwell-patterned PDMS chip.

    Science.gov (United States)

    Wang, Tanyu; Zhang, Mohan; Dreher, Dakota D; Zeng, Yong

    2013-11-07

    Quantitative detection of low abundance proteins is of significant interest for biological and clinical applications. Here we report an integrated microfluidic solid-phase ELISA platform for rapid and ultrasensitive detection of proteins with a wide dynamic range. Compared to the existing microfluidic devices that perform affinity capture and enzyme-based optical detection in a constant channel volume, the key novelty of our design is two-fold. First, our system integrates a microwell-patterned assay chamber that can be pneumatically actuated to significantly reduce the volume of chemifluorescent reaction, markedly improving the sensitivity and speed of ELISA. Second, monolithic integration of on-chip pumps and the actuatable assay chamber allow programmable fluid delivery and effective mixing for rapid and sensitive immunoassays. Ultrasensitive microfluidic ELISA was demonstrated for insulin-like growth factor 1 receptor (IGF-1R) across at least five orders of magnitude with an extremely low detection limit of 21.8 aM. The microwell-based solid-phase ELISA strategy provides an expandable platform for developing the next-generation microfluidic immunoassay systems that integrate and automate digital and analog measurements to further improve the sensitivity, dynamic ranges, and reproducibility of proteomic analysis.

  20. A novel approach for osteocalcin detection by competitive ELISA using porous silicon as a substrate.

    Science.gov (United States)

    Rahimi, Fereshteh; Mohammadnejad Arough, Javad; Yaghoobi, Mona; Davoodi, Hadi; Sepehri, Fatemeh; Amirabadizadeh, Masood

    2017-11-01

    In this study, porous silicon (PSi) was utilized instead of prevalent polystyrene platforms, and its capability in biomolecule screening was examined. Here, two types of porous structure, macroporous silicon (Macro-PSi) and mesoporous silicon (Meso-PSi), were produced on silicon wafers by electrochemical etching using different electrolytes. Moreover, both kinds of fresh and oxidized PSi samples were investigated. Next, osteocalcin as a biomarker of the bone formation process was used as a model biomarker, and the colorimetric detection was performed by competitive enzyme-linked immunosorbent assay (ELISA). Both Macro-PSi and Meso-PSi substrates in the oxidized state, specifically the Meso-porous structure, were reported to have higher surface area to volume ratio, more capacitance of surface-antigen interaction, and more ability to capture antigen in comparison with the prevalent platforms. Moreover, the optical density signal of osteocalcin detected by the ELISA technique was notably higher than the common platforms. Based on the findings of this study, PSi can potentially be used in the ELISA to achieve better results and consequently more sensitivity. A further asset of incorporating such a nanometer structure in the ELISA technique is that the system response to analyte concentration could be maintained by consuming lower monoclonal antibody (or antigen) and consequently reduces the cost of the experiment. © 2016 International Union of Biochemistry and Molecular Biology, Inc.

  1. Transfer of Trypanosoma ELISA technology to Onderstepoort Veterinary Institute, South Africa

    International Nuclear Information System (INIS)

    Waal, D.T. de

    2000-01-01

    Following a brief historical overview of trypanosomosis in South Africa, the present day role is explained of the Onderstepoort Veterinary Institute (OVI) in assisting disease diagnosis and surveillance. Production and distribution of ELISA kits will be initiated at OVI, initially for brucellosis and at a later stage for trypanosomosis. (author)

  2. Evaluation of an indirect elisa for the diagnosis of bovine brucellosis in Patagonia, Argentina

    International Nuclear Information System (INIS)

    Uzal, F.A.; Carrasco, E.A.; Robles, C.A.; Echaide, S.

    1998-01-01

    Control and eradication of bovine brucellosis is usually based on the serological detection of antibodies. In Argentina, the Rose Bengal test (RB) and the Buffered Plate antigen test (BPA) are the two screening test officially recognized, while the 2-mercaptoethanol test (2ME) and the Tube Agglutination test (SAT) are the confirmatory assays currently in use. In order to improve the serological diagnosis of bovine brucellosis in Patagonia, Argentina, an indirect ELISA kit produced by the Joint FAO/IAEA Division was evaluated. Sera from negative non-vaccinated, negative but vaccinated and positive animals were tested by all the above techniques. The specificity of the I-ELISA (99.6% and 99.7%) was similar to that of the BPA, RB, 2ME and Complement Fixation test (CF) when used to test sera from non-vaccinated, negative and vaccinated, negative animals, respectively. The sensitivity of the I-ELISA (98%) was higher than the BPA test (96%) and the CF test (95,2%). The I-ELISA kit evaluated in this study was thought to be a valuable tool for the diagnosis of bovine brucellosis in Patagonia region where little epidemiological information is available about this disease and where large numbers of sera should be tested to obtain such information. (author)

  3. ELISA indireto para detecção de Ig G anti-vírus da doença de newcastle em soro de codorna

    OpenAIRE

    Daniela Duarte de Oliveira

    2004-01-01

    Foram desenvolvidos e comparados dois ELISAs para detecção de IgG de codorna (Coturnix coturnix japônica) contra o vírus da doença de Newcastle (VDN). Um deles utilizando anticorpo secundário de camundongo anti-IgG de codorna e o outro, conjugado anti-IgG de galinha. Para a produção de anticorpo secundário (IgG de camundongo anti-IgG de codorna), métodos de purificação de IgG de codorna foram avaliados utilizando 30 amostras de soros e gemas de ovos de codornas, confirmados posteriormente por...

  4. Polymerase chain reaction and blood culture in blood donors screened by ELISA test for Chagas' disease

    Directory of Open Access Journals (Sweden)

    Andréa Tieko Kinoshita-Yanaga

    2011-03-01

    Full Text Available The objective of this study was to evaluate, through blood culture and PCR, the results of the ELISA for Chagas' disease in the screening of blood donors in the public blood-supply network of the state of Paraná, Brazil, and to map the epidemiological profile of the donors with respect to their risk of infection by Trypanosoma cruzi. The negative and positive results of the ELISA were confirmed by blood culture and PCR for 190/191 individuals (99.5%. For one individual (0.5%, the ELISA was inconclusive, blood culture and IIF were negative, and IHA and PCR positive. Three individuals (1.6% were positive for T. cruzi on all the tests. Donors were predominantly female, and natives of Paraná, of rural origin, had observed or been informed of the presence of the vector in the municipalities where they resided, had never received a blood transfusion, had donated blood 1 to 4 times, and reported no cases of Chagas' disease in their families. We concluded that PCR and blood culturing have excellent potential for confirming the results of the ELISA, and that candidate blood donors with negative or positive tests have a similar risk of infection by T. cruzi, indicating that the ELISA test is sufficiently safe for screening blood prior to use.O objetivo deste estudo foi avaliar, pela hemocultura e PCR, os resultados do teste ELISA utilizado para doença de Chagas na triagem de doadores de sangue na rede pública do Estado do Paraná, Brasil, e traçar o perfil epidemiológico dos doadores quanto ao risco de infecção pelo Trypanosoma cruzi. Os resultados negativos e positivos do ELISA foram confirmados pela hemocultura e PCR em 190/191 indivíduos (99,5%. Para um indivíduo (0,5%, o teste de ELISA foi inconclusivo, hemocultura e IFI foram negativas, HAI e PCR foram positivas. Três indivíduos (1,6% foram positivos para T. cruzi em todos os testes. A maioria dos doadores era do sexo feminino, oriundos do Estado do Paraná, de origem rural, tinham

  5. O uso de Elisa como ferramenta complementar para o controle da tuberculose bovina no Brasil

    Directory of Open Access Journals (Sweden)

    Walter Lilenbaum

    2006-04-01

    Full Text Available A detecção de animais infectados é um dos mais importantes fatores envolvidos no controle da tuberculose e, com algumas variações, é realizado através de testes intradérmicos de tuberculinização. No entanto, animais negativos aos testes intradérmicos podem estar infectados e representam uma importante ameaça aos programas de erradicação da tuberculose. Apesar deste conhecido fenômeno, o uso de ELISA não é rotina nestes programas. Nosso objetivo foi o de descrever experiências do uso a campo de ELISA na detecção de animais anérgicos no Rio de Janeiro, Brasil. Dentre 18 rebanhos envolvidos em um programa de controle da tuberculose, dois apresentaram animais infectados negativos aos testes intradérmicos, o que atrasou e comprometeu o sucesso do programa, com severas perdas econômicas. A infecção nestes animais foi identificada através de ELISA e confirmada pelo isolamento de M.bovis nas lesões pulmonares. Desta forma foram considerados como a mais provável fonte de infecção e responsáveis pela manutenção da enfermidade nos rebanhos. Sem o uso de testes sorológicos como ELISA estes animais provavelmente permaneceriam nos rebanhos perpetuando a infecção e a erradicação da enfermidade seria impossível. Em conclusão, sugere-se o uso de ELISA como uma valiosa ferramenta complementar para identificar animais anérgicos que possam atuar como reservatórios do agente nos rebanhos.

  6. Porøse materialer

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place

    2000-01-01

    Dette undervisningsnotat er en samling af noter, der refererer til den indledende del af kurset Materialmekanik og Porøse materailer på Insitut for Bærende Konstruktiner og Materialer (BKM).......Dette undervisningsnotat er en samling af noter, der refererer til den indledende del af kurset Materialmekanik og Porøse materailer på Insitut for Bærende Konstruktiner og Materialer (BKM)....

  7. Comparative study of the enzyme linked immunosorbent assay (ELISA) and two radioimmunoassays (RIA'S) for in-sulin

    Energy Technology Data Exchange (ETDEWEB)

    Klimes, I; Jurcovicova, J; Palkovic, M [Slovenska Akademia Vied, Bratislava (Czechoslovakia). Ustav Experimentalnej Endokrinologie

    1978-06-30

    The results of the quality control tests for enzyme linked immunosorbent assay (ELISA) were compared with the results of two different radioimmunoassays (RIA'S) for insulin. Using the manufacturer's procedure for the ELISA kit we found that the analytical variables such as assay sensitivity, recovery study and the 50% binding intercept were in good agreement with those obtained with the RIA method.

  8. Development and evaluation of a sandwich ELISA for quantification of the 20S proteasome in human plasma

    DEFF Research Database (Denmark)

    Dutaud, Dominique; Aubry, Laurent; Henry, Laurent

    2002-01-01

    Because quantification of the 20S proteasome by functional activity measurements is difficult and inaccurate, we have developed an indirect sandwich enzyme-linked immunosorbent assays (ELISA) for quantification of the 20S proteasome in human plasma. This sandwich ELISA uses a combination...

  9. A comparison of ELISA methods for the determination of human serum antibodies to Haemophilus influenzae type b

    NARCIS (Netherlands)

    van Gageldonk PGM; Mariani M; Berbers GAM; LVO-BI; Centro Ricerche; CHIRON S.p.A.; Siena; Italy/Laboratorio di Immunochimica e Sierologia Sperimentale/Departimento Immunologia

    1998-01-01

    Een vergelijking tussen de non-competitieve ELISA van Phipps et al., de klassieke radio-antigeen bindings assay (RABA) en de nieuw ontwikkelde Chiron competitieve ELISA voor de bepaling van anti-Hib polysaccharide (HibPs) antistof concentraties in humane sera wordt beschreven in het rapport. Voor

  10. AN ENZYME LINKED IMMUNOSORBENT ASSAY (ELISA) METHOD FOR MONITORING 2,4 DICHLOROPHENOXYACETIC ACID (2,4-D) EXPOSURES

    Science.gov (United States)

    Abstract describes a streamlined ELISA method developed to quantitatively measure 2,4-D in human urine samples. Method development steps and comparison with gas chromatography/mass spectrometry are presented. Results indicated that the ELISA method could be used as a high throu...

  11. Diagnosis of theileria equi infections in horses in the Azores using cELISA and nested PCR

    Science.gov (United States)

    Equine piroplasmosis is a tick-borne disease of equids that is often caused by the parasite Theileria equi. We applied competitive ELISA (cELISA) and nested PCR diagnostic methods to detect this parasite in horses by screening 162 samples from mainland Portugal where the parasite is endemic, and 143...

  12. Development of duplex RT-PCR-ELISA for the simultaneous detection of hepatitis A virus and hepatitis E virus.

    Science.gov (United States)

    Tahk, Hongmin; Lee, Min Hwa; Lee, Kang Bum; Cheon, Doo-Sung; Choi, Changsun

    2011-07-01

    This study aimed to develop a specific and sensitive duplex reverse transcription polymerase chain reaction enzyme-linked immunosorbent assay (duplex RT-PCR-ELISA) for hepatitis A virus (HAV) and hepatitis E virus (HEV). Duplex RT-PCR-ELISA could detect and differentiate HAV and HEV with specific probes. When ELISA technique was used to detect probe-bound RT-PCR products, duplex RT-PCR-ELISA could detect as little as 0.1 ng/μL HAV and HEV from clinical samples. Human norovirus, enterovirus, poliovirus, murine norovirus and feline calicivirus were used for the specificity test; all were negative. Therefore duplex RT-PCR-ELISA can be used for the simultaneous detection of HAV and HEV in contaminated fecal samples. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Case study on human α1-antitrypsin: Recombinant protein titers obtained by commercial ELISA kits are inaccurate

    DEFF Research Database (Denmark)

    Hansen, Henning Gram; Kildegaard, Helene Faustrup; Min Lee, Gyun

    2016-01-01

    Accurate titer determination of recombinant proteins is crucial for evaluating protein production cell lines and processes. Even though enzyme-linked immunosorbent assay (ELISA) is the most widely used assay for determining protein titer, little is known about the accuracy of commercially available...... ELISA kits. We observed that estimations of recombinant human ø1-antitrypsin (rø1AT) titer by Coomassie-stained SDS-PAGE gels did not correspond to previously obtained titers obtained by a commercially available ELISA kit. This prompted us to develop two independent quantification assays based...... on biolayer interferometry and reversed-phase high-performance liquid chromatography. We compared the rø1AT titer obtained by these assays with three different off-the-shelf ELISA kits and found that the ELISA kits led to inconsistent results. The data presented here show that recombinant protein titers...

  14. Matrix effects in applying mono- and polyclonal ELISA systems to the analysis of weathered oils in contaminated soil.

    Science.gov (United States)

    Pollard, S J T; Farmer, J G; Knight, D M; Young, P J

    2002-01-01

    Commercial mono- and polyclonal enzyme-linked immunosorbent assay (ELISA) systems were applied to the on-site analysis of weathered hydrocarbon-contaminated soils at a former integrated steelworks. Comparisons were made between concentrations of solvent extractable matter (SEM) determined gravimetrically by Soxhlet (dichloromethane) extraction and those estimated immunologically by ELISA determination over a concentration range of 2000-330,000 mg SEM/kg soil dry weight. Both ELISA systems tinder-reported for the more weathered soil samples. Results suggest this is due to matrix effects in the sample rather than any inherent bias in the ELISA systems and it is concluded that, for weathered hydrocarbons typical of steelworks and coke production sites, the use of ELISA requires careful consideration as a field technique. Consideration of the target analyte relative to the composition of the hydrocarbon waste encountered appears critical.

  15. Standardization and application of indirect ELISA for diagnosis of Mycoplasma bovis in bovine blood serum samples

    Directory of Open Access Journals (Sweden)

    Samira Moraes Cunha de Mesquita

    2015-06-01

    Full Text Available ABSTRACT. Mesquita S.M.C., Mansur F.J., Nascimento E.R., Barreto M.L. & Kimura L.M.S. [Standardization and application of indirect ELISA for diagnosis of Mycoplasma bovis in bovine blood serum samples.] Padroniza- ção e aplicação de ELISA indireto para diagnóstico de Mycoplasma bovis em amostras de soro sanguíneo bovino. Revista Brasileira de Medicina Veterinária, 37(2:101-107, 2015. Universidade Federal Fluminense, Faculdade de Veteriná- ria, Rua Vital Brazil Filho, 64, Vital Brazil, Niterói, RJ 24230-340, Brasil. E-mail: samira.veterinaria@gmail.com International researchers presented results indicating frequent involvement of Mycoplasma spp. as a causative agent of mastitis in cattle, associating its presence with significant economic losses to farmers. Mycoplasma bovis is the species most reported and relevant, because it causes more severe disease. The level of antibodies against M. bovis remains high for several months and can be detected by ELISA. The aim of this work was to develop an indirect ELISA with whole cell antigen of M. bovis (strain Donetta PG 45 with subsequent application in bovine blood serum samples for detection of antibodies against M. bovis. The immunization of cows A and B by inoculating an immunogen against M. bovis to obtain hyperimmune blood serum was the first stage of this work, then the stage of standardization of ELISA was proceeded. The concentration of 2 mg of antigen/mL for coating the microtiter plates was decided by statistical analyses. The optical density value 0,2 was determined as the limit of reactivity discrimination of samples (the cut-off point. The hyperimmune blood serum sample of the cow A (collected 30 days after immunization was chosen as the positive control and, the fetal calf serum was chosen as negative control of the assay. In addition, the ideal optimal dilutions found for blood serum samples was 1:400 and for conjugate was 1:10.000 and the substrate used was the ortho

  16. ELISA cualitativo de IgA anti-Lipopolisacárido de Vibrio cholerae en saliva de humanos

    Directory of Open Access Journals (Sweden)

    Judith Mónica del Campo

    2002-03-01

    Full Text Available Se estandarizó un ELISA para detectar el principal antígeno inductor de protección de Vibrio cholerae en saliva IgA contra el lipopolisacárido (LPS. El estudio se llevó a cabo en voluntarios que fueron inoculados por vía oral con dosis de 0, 107, 108, 109 unidades formadoras de colonias (ufc del candidato vacunal El Tor Ogawa, cepa 638. Las muestras de saliva fueron tomadas de forma seriada, a los 0, 7, 8, 9, 10 y 14 días postinoculación. Se consideró seroconversión si las densidades ópticas eran superiores al nivel de corte y si los incrementos después de inmunizar duplicaban los valores antes de la inmunización. Los resultados, al ser comparados con los grupos experimentales, condición individuos inoculados y los placebos, demostraron que la técnica tiene una sensibilidad del 93,3%, una especificidad del 96,0%, un valor predictivo positivo de 98,2% y negativo de 85,7%, y una eficiencia del 94,1%. Se demostró la presencia de IgA anti LPS en saliva de los individuos inoculados con el candidato vacunal, con una mayor concentración de anticuerpos con el inóculo de (109 ufc y se obtuvo la máxima positividad a los nueve días.

  17. Construction of an optical test-bed for eLISA

    International Nuclear Information System (INIS)

    Lieser, Maike; Isleif, K-S; Schuster, S; Tröbs, M; Veith, S; Heinzel, G; Danzmann, K; Fitzsimons, E; Killow, C; Perreur-Lloyd, M; Robertson, D; Ward, H

    2016-01-01

    In the planned eLISA mission a key part of the system is the optical bench that holds the interferometers for reading out the inter-spacecraft distance and the test mass position. We report on ongoing technology development for the eLISA optical system like the back-link between the optical benches and the science interferometer where the local beam is interfered with the received beam from the distant spacecraft. The focus will be on a setup to investigate the tilt-to-pathlength coupling in the science interferometer. To test the science interferometer in the lab a second bench providing a laser beam and a reference interferometer is needed. We present a setup with two ultra-stable low expansion glass benches and bonded optics. To suppress the tilt-to-pathlength coupling to the required level (few μm/rad) imaging optics are placed in front of the interferometer photo diodes. (paper)

  18. The use of polyvinyl alcohol glutaraldehyde as solid-phase in ELISA for plague

    Directory of Open Access Journals (Sweden)

    Aureci Maria Araujo

    1996-04-01

    Full Text Available Discs of polyvinyl alcohol cross-linked with glutaraldehyde were synthesized under acid catalysis (H2SO4. Then, the antigen F1 purified from Yersinia pestis was covalently linked to this modified polymer. Afterwards, an enzyme-linked immunosorbent assay (ELISA was established for the diagnosis of plague in rabbit and human. The best conditions for the method were achieved by using 1.3 ¼g of F1 prepared in 0.067 M phosphate buffer, pH 7.2, containing 1 M NaCl (PBS; anti-IgG peroxidase conjugate diluted 6,000 times and as a blocking agent 3% w/v skim milk in PBS. The titration of positive rabbit serum according to this procedure detected antibody concentrations up to 1:12,800 times. The present method, the conventional ELISA and passive haemagglutination assay are compared.

  19. Quantitative Detection of Horse Contamination in Cooked Meat Products by ELISA.

    Science.gov (United States)

    Thienes, Cortlandt P; Masiri, Jongkit; Benoit, Lora A; Barrios-Lopez, Brianda; Samuel, Santosh A; Cox, David P; Dobritsa, Anatoly P; Nadala, Cesar; Samadpour, Mansour

    2018-05-01

    Concerns about the contamination of meat products with horse meat and new regulations for the declaration of meat adulterants have highlighted the need for a rapid test to detect horse meat adulteration. To address this need, Microbiologique, Inc., has developed a sandwich ELISA that can quantify the presence of horse meat down to 0.1% (w/w) in cooked pork, beef, chicken, goat, and lamb meats. This horse meat authentication ELISA has an analytical sensitivity of 0.000030 and 0.000046% (w/v) for cooked and autoclaved horse meat, respectively, and an analytical range of quantitation of 0.05-0.8% (w/v) in the absence of other meats. The assay is rapid and can be completed in 1 h and 10 min. Moreover, the assay is specific for cooked horse meat and does not demonstrate any cross-reactivity with xenogeneic cooked meat sources.

  20. LDRD final report on microencapsulated immunoreagents for development of one-step ELISA

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, C.C.; Singh, A.K.

    1997-08-01

    Microencapsulation of biological macromolecules was investigated as a method for incorporating the necessary immunoreagents into an improved enzyme-linked immunosorbant assay (ELISA) package that would self-develop. This self-contained ELISA package would eliminate the need for a trained technician to perform multiple additions of immunoreagent to the assay. Microencapsulation by insolution drying was selected from the many available microencapsulation methods, and two satisfactory procedures for microencapsulation of proteins were established. The stability and potential for rapid release of protein from these microencapsulates was then evaluated. The results suggest that the chosen method for protein entrapment produces microcapsules with a considerable amount of protein in the walls making these particular microcapsules unsuitable for their intended use.

  1. Detection of Double White Dwarf Binaries with Gaia, LSST and eLISA

    Science.gov (United States)

    Korol, V.; Rossi, E. M.; Groot, P. J.

    2017-03-01

    According to simulations around 108 double degenerate white dwarf binaries are expected to be present in the Milky Way. Due to their intrinsic faintness, the detection of these systems is a challenge, and the total number of detected sources so far amounts only to a few tens. This will change in the next two decades with the advent of Gaia, the LSST and eLISA. We present an estimation of how many compact DWDs with orbital periods less than a few hours we will be able to detect 1) through electromagnetic radiation with Gaia and LSST and 2) through gravitational wave radiation with eLISA. We find that the sample of simultaneous electromagnetic and gravitational waves detections is expected to be substantial, and will provide us a powerful tool for probing the white dwarf astrophysics and the structure of the Milky Way, letting us into the era of multi-messenger astronomy for these sources.

  2. Agricultural production - Phase 2. Indonesia. National training course on ELISA for seradiagnosis of animal diseases (4)

    International Nuclear Information System (INIS)

    Spencer, T.

    1992-01-01

    This report details and UNDP/FAO/IAEA consultancy undertaken from Monday 13 February to Saturday 25 February 1989. The purpose of the consultancy was to provide practical and theoretical training to Indonesian scientists in ELISA technology. This occurred under the program title of ''National Training Course on the Use of ELISA for Serodiagnosis of Animal Diseases, with Emphasis on Brucellosis''. The course was held in the Bacteriology Department, Research Institute for Veterinary Sciences (Balitvet), Bogor, Indonesia. The majority of the 19 participants came from the Regional Disease Investigation Centre Laboratories within Indonesia. The principal course instructor was Dr. Richard Jacobson who was assisted by Dr. Larry McClure, Dr. Susan Sutherland, Dr. Mark Eisler, Dr. Barry Patten and myself. The course concluded with a one day seminar organized by BATAN, DITKESWAN and BALITVET entitled ''Bovine Brucellosis: A Challenging Disease for Indonesia'' which was attended by approximately fifty people. Refs and tabs

  3. Evaluation of antigen and antibody ELISA's for epidemiological surveys of tsetse-transmitted trypanosomosis in cattle

    International Nuclear Information System (INIS)

    Eisler, M.C.; Hopkins, J.S.; Machila, N.; Bossche, P. van den; Peregrine, A.S.; Luckins, A.G.

    2000-01-01

    Sensitivity and specificity of the FAO/IAEA antigen-detection enzyme-linked immunosorbent assay (ELISA) kits for diagnosis of bovine trypanosomosis were investigated using sera from experimental cattle infected by tsetse challenge with cloned populations of Trypanosoma congolense (3 populations) or T. vivax (1 population). The kits are based on monoclonal antibodies that recognise internal antigens of tsetse-transmitted trypanosomes. Ten cattle were infected with each trypanosome population for at least 60 days, and in combination with uninfected cohorts (n=16) were used in a double-blind study design. Sensitivity and specificity of the tests depended on the choice of positive-negative thresholds expressed as percent positivity with respect to the median OD of 4 replicates of the strong positive reference serum provided with the kit. In general, while overall specificities were high, sensitivities of the antigen-ELISA's were poor. For example, at a cut-off of 5% positivity, the sensitivities of the antigen-ELISA's were 11% for samples (n=1162) from T. congolense infected cattle (n=30), and 24% for samples (n=283) from T. vivax infected cattle (n=10). The corresponding specificity values were 95% and 79%, respectively. There were no values of the positive-negative threshold at which both sensitivity and specificity were satisfactory. Trypanosome species-specificities of the antigen-ELISA's were also poor. Sensitivity and species-specificity of the antigen-ELISA for T. brucei infections were not investigated. The indirect ELISA for the detection of anti-trypanosomal antibodies in bovine serum was adapted for use with dried blood spots on filter paper, and standardised using a strong positive reference serum and the percent positivity system of data expression. The antibody-ELISA was evaluated in Zambia for use in epidemiological surveys of the prevalence of tsetse-transmitted bovine trypanosomosis. Known negative samples (sera, n=209; blood spots, n=466) were

  4. ELISA validation and determination of cut-off level for chloramphenicol residues in honey

    Directory of Open Access Journals (Sweden)

    Biernacki Bogumił

    2015-09-01

    Full Text Available An analytical validation of a screening ELISA for detection of chloramphenicol (CAP in honey was conducted according to the Commission Decision 2002/657/EC and Guidelines for the Validation of Screening Methods for Residues of Veterinary Medicines. The analyte was extracted from honey with a water and ethyl acetate mixture, and CAP concentrations were measured photometrically at 450 nm. The recovery rate of the analyte from spiked samples was 79%. The cut-off level of CAP in honey as the minimum recovery (0.17 units was established. Detection capability (CCβ was fixed at 0.25 μg kg−1. No relevant interferences between matrix effects and structurally related substances including florfenicol and thiamphenicol were observed. The ELISA method should be useful for determination of CAP residues in honey monitoring.

  5. Rapid Enhanced MM3-COPRO ELISA for Detection of Fasciola Coproantigens

    Science.gov (United States)

    Martínez-Sernández, Victoria; Orbegozo-Medina, Ricardo A.; González-Warleta, Marta; Mezo, Mercedes; Ubeira, Florencio M.

    2016-01-01

    ELISA-based methods of detecting Fasciola cathepsins in feces are powerful techniques for diagnosing infections by F. hepatica and F. gigantica. In the last decade, the in-house MM3-COPRO ELISA and its commercial version BIO K 201 (BIO X Diagnostics, Belgium) have been recognized as useful tools for detecting early infections by such trematodes and for monitoring the efficacy of anthelmintic treatments in human and animal species, as they provide some advantages over classic fecal egg counts. However, the sensitivity of MM3-COPRO ELISA can sometimes be compromised by the high variability in the concentration of cathepsins in fecal samples throughout the biological cycle of Fasciola (mainly in cattle) and by differences in the between-batch performance of peroxidase-labeled anti-mouse IgG polyclonal antibodies. To prevent such problems, we investigated whether the incorporation of a commercial streptavidin-polymerized horseradish peroxidase conjugate, in order to reveal bound biotinylated monoclonal antibody MM3, can improve the sensitivity of the MM3-COPRO ELISA. We observed that inclusion of this reagent shifted the previous detection limit of the assay from 0.6 ng/mL to 150 pg/mL and that the modified test is able to identify infection in cows harboring only one fluke. Moreover, we demonstrated that maximal OD values can be achieved with short incubations (30 min each step) at RT with shaking, rather than standard incubations, which significantly accelerates the diagnostic procedure. Finally, we did not find a significant correlation between coproantigen concentration and parasite burden in cattle, which may be due to the low parasite burden (1–10 adult flukes) of the animals used in the present study. As the usefulness of the classic MM3-COPRO test for detecting animal and human infections has already been demonstrated, it is expected that the improvements reported in this study will add new insights into the diagnosis and control of fasciolosis. PMID:27438470

  6. Performance of immunochromatographic and ELISA tests for detecting fallow deer infected with Mycobacterium bovis.

    Science.gov (United States)

    Boadella, M; Barasona, J A; Diaz-Sanchez, S; Lyashchenko, K P; Greenwald, R; Esfandiari, J; Gortazar, C

    2012-04-01

    Fallow deer (Dama dama) are widely distributed as natural or naturalised populations, as well as in game parks and deer farms. We used 157 fallow deer sampled in populations considered to be Mycobacterium tuberculosis complex (MTC) free and 73 Mycobacterium bovis-infected fallow deer confirmed postmortem by culture to evaluate the diagnostic performance of two tests for the detection of anti-mycobacterial antibodies: the dual path platform (DPP) VetTB assay and the bovine purified protein derivative (bPPD) ELISA. We also compared their sensitivity with that of the skin test, analyzed the effect of haemolysis degree on the antibody detection and described the relationship between the test readings and presence/absence of gross tuberculosis (TB) compatible lesions. Sensitivity of bPPD ELISA was 51% at a specificity of 96%. Depending on the cut-off value selected, the sensitivity of DPP VetTB ranged from 62 to 71%, while its specificity was 88-95%. In the subgroup of M. bovis-infected deer for which the skin test data were available (33 of 73); this method detected 76% of culture-positive animals, although the specificity of the intradermal test was not determined in this study. When the DPP VetTB and skin test data were combined, the resulting sensitivity obtained in this sub-group of M. bovis-infected deer increased to 97%. Gross pathology identified TB compatible lesions (TBL) in 89% culture-confirmed fallow deer. The infected animals with visible lesions had significantly higher readings in the DPP VetTB, but not in the bPPD ELISA. Only high levels of haemolysis decreased antibody test sensitivity and this effect was more evident for the bPPD ELISA. The results allowed inferring a number of management recommendations for rapid detection of MTC infection in live fallow deer and in surveys on hunter-harvested cervids. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Evaluation of methods to reduce background using the Python-based ELISA_QC program.

    Science.gov (United States)

    Webster, Rose P; Cohen, Cinder F; Saeed, Fatima O; Wetzel, Hanna N; Ball, William J; Kirley, Terence L; Norman, Andrew B

    2018-05-01

    Almost all immunological approaches [immunohistochemistry, enzyme-linked immunosorbent assay (ELISA), Western blot], that are used to quantitate specific proteins have had to address high backgrounds due to non-specific reactivity. We report here for the first time a quantitative comparison of methods for reduction of the background of commercial biotinylated antibodies using the Python-based ELISA_QC program. This is demonstrated using a recombinant humanized anti-cocaine monoclonal antibody. Several approaches, such as adjustment of the incubation time and the concentration of blocking agent, as well as the dilution of secondary antibodies, have been explored to address this issue. In this report, systematic comparisons of two different methods, contrasted with other more traditional methods to address this problem are provided. Addition of heparin (HP) at 1 μg/ml to the wash buffer prior to addition of the secondary biotinylated antibody reduced the elevated background absorbance values (from a mean of 0.313 ± 0.015 to 0.137 ± 0.002). A novel immunodepletion (ID) method also reduced the background (from a mean of 0.331 ± 0.010 to 0.146 ± 0.013). Overall, the ID method generated more similar results at each concentration of the ELISA standard curve to that using the standard lot 1 than the HP method, as analyzed by the Python-based ELISA_QC program. We conclude that the ID method, while more laborious, provides the best solution to resolve the high background seen with specific lots of biotinylated secondary antibody. Copyright © 2018. Published by Elsevier B.V.

  8. Antigenisitas, Sensitivitas, dan Spesifisitas Protein Toxocara canis pada Pemeriksaan Antibodi Serum Mencit dengan Indirect-ELISA

    Directory of Open Access Journals (Sweden)

    Sri Subekti Bendryman

    2015-05-01

    Full Text Available The aim of this research were to determine antigenicity, sensitivity, and specificity of Toxocara canisprotein used as antigen in indirect-ELISA for the detection antibody against the worm in the infected hostin order to proper diagnose kit. The design used was true experimental, with Post-test Only ControlGroups Design. Mouse was immunized with various worm homogenates used to antigenicity, sensitivityand specificity tests of T. canis protein with indirect-ELISA technique. The independence variable werevarious immunogens (homogenates; the dependence variables were antigenicity, sensitivity and specificityvalues interpreted by optical density (OD value of mouse sera; and controlled variable were mouse strain,feed and retrieval time of sera. The result showed that OD values of mouse sera immunized with T. canisand T.cati homogenate were signicantly difference (p<0.01 as compared to those immunized withAncylostoma spp., Dipylidium caninum and control sera. Using the diagnosis based on the finding ofToxocara, the sensitivity of OD value by ELISA result from mouse sera immunized with Toxocara spp.homogenate were 100%. Using negative OD value by ELISA from mouse sera immunized with Ancylostomaspp. and D. caninum homogenate, the specificity of the test was 87.5%. In conclusion, protein of T.canishas the same antigenicity against anti-T. canis and anti-T. cati sera, but they had the lower antigenicityagainst anti-Ancylostoma spp. and anti-D.caninum sera. As the sensitivity value of 100% and specificityvalue of 87.5%, in detecting antibody against toxocariasis, the possibility of obtaining false positive was12.5%.

  9. Titration ELISA as a Method to Determine the Dissociation Constant of Receptor Ligand Interaction.

    Science.gov (United States)

    Eble, Johannes A

    2018-02-15

    The dissociation constant describes the interaction between two partners in the binding equilibrium and is a measure of their affinity. It is a crucial parameter to compare different ligands, e.g., competitive inhibitors, protein isoforms and mutants, for their binding strength to a binding partner. Dissociation constants are determined by plotting concentrations of bound versus free ligand as binding curves. In contrast, titration curves, in which a signal that is proportional to the concentration of bound ligand is plotted against the total concentration of added ligand, are much easier to record. The signal can be detected spectroscopically and by enzyme-linked immunosorbent assay (ELISA). This is exemplified in a protocol for a titration ELISA that measures the binding of the snake venom-derived rhodocetin to its immobilized target domain of α2β1 integrin. Titration ELISAs are versatile and widely used. Any pair of interacting proteins can be used as immobilized receptor and soluble ligand, provided that both proteins are pure, and their concentrations are known. The difficulty so far has been to determine the dissociation constant from a titration curve. In this study, a mathematical function underlying titration curves is introduced. Without any error-prone graphical estimation of a saturation yield, this algorithm allows processing of the raw data (signal intensities at different concentrations of added ligand) directly by mathematical evaluation via non-linear regression. Thus, several titration curves can be recorded simultaneously and transformed into a set of characteristic parameters, among them the dissociation constant and the concentration of binding-active receptor, and they can be evaluated statistically. When combined with this algorithm, titration ELISAs gain the advantage of directly presenting the dissociation constant. Therefore, they may be used more efficiently in the future.

  10. Rapid Enhanced MM3-COPRO ELISA for Detection of Fasciola Coproantigens.

    Science.gov (United States)

    Martínez-Sernández, Victoria; Orbegozo-Medina, Ricardo A; González-Warleta, Marta; Mezo, Mercedes; Ubeira, Florencio M

    2016-07-01

    ELISA-based methods of detecting Fasciola cathepsins in feces are powerful techniques for diagnosing infections by F. hepatica and F. gigantica. In the last decade, the in-house MM3-COPRO ELISA and its commercial version BIO K 201 (BIO X Diagnostics, Belgium) have been recognized as useful tools for detecting early infections by such trematodes and for monitoring the efficacy of anthelmintic treatments in human and animal species, as they provide some advantages over classic fecal egg counts. However, the sensitivity of MM3-COPRO ELISA can sometimes be compromised by the high variability in the concentration of cathepsins in fecal samples throughout the biological cycle of Fasciola (mainly in cattle) and by differences in the between-batch performance of peroxidase-labeled anti-mouse IgG polyclonal antibodies. To prevent such problems, we investigated whether the incorporation of a commercial streptavidin-polymerized horseradish peroxidase conjugate, in order to reveal bound biotinylated monoclonal antibody MM3, can improve the sensitivity of the MM3-COPRO ELISA. We observed that inclusion of this reagent shifted the previous detection limit of the assay from 0.6 ng/mL to 150 pg/mL and that the modified test is able to identify infection in cows harboring only one fluke. Moreover, we demonstrated that maximal OD values can be achieved with short incubations (30 min each step) at RT with shaking, rather than standard incubations, which significantly accelerates the diagnostic procedure. Finally, we did not find a significant correlation between coproantigen concentration and parasite burden in cattle, which may be due to the low parasite burden (1-10 adult flukes) of the animals used in the present study. As the usefulness of the classic MM3-COPRO test for detecting animal and human infections has already been demonstrated, it is expected that the improvements reported in this study will add new insights into the diagnosis and control of fasciolosis.

  11. Significance of Serology by Multi-Antigen ELISA for Tissue Helminthiases in Korea

    Science.gov (United States)

    2017-01-01

    It is clinically important to differentiate tissue-invading helminthiasis. The purpose of this study was to assess the specific immunoglobulin G (IgG) antibody positive rates for clonorchiasis, paragonimiasis, cysticercosis, and sparganosis 4 helminthiases from 1996 to 2006 using multi-antigen enzyme-linked immunosorbent assay (ELISA) in Korea. Results of 6,017 samples, which were referred to our institute for serodiagnosis, were analyzed. The subjects with positive serum IgG antibodies were 1,502 (25.0%) for any of the 4 helminthiases. The overall positive numbers for clonorchiasis, paragonimiasis, cysticercosis, and sparganosis were 728 (12.1%), 166 (2.8%), 729 (12.1%), and 263 (4.4%), respectively. The positive serologic reaction to multi-antigens was determined in 309 (20.6%) of the 1,502 total seropositive subjects. Those with multi-antigen positivity were regarded as positive for the antigen of strongest reaction but cross-reaction to others with weak positive reaction. Annual seropositive rates for those 4 tissue helminthiases ranged from 12.1% to 35.7%. The highest rate was observed in age from 60 to 69 years old and prevalence of men (27.4%; 1,030/3,763) was significantly higher than of women (19.1%; 332/1,741). Hospital records of 165 ELISA positive patients were reviewed to confirm correlation with their clinical diagnosis. Paragonimiasis was highly correlated as 81.8% (9/11), cysticercosis 29.9% (20/67), clonorchiasis 29.0% (20/69), and sparganosis 11.1% (2/18). In conclusion, the multi-antigen ELISA using 4 helminth antigens is useful to differentiate suspected tissue-invading helminthiases, especially ELISA diagnosis of paragonimiasis is reliable. The seropositivity is still high among suspected patients in Korea. PMID:28581268

  12. Detection of Foot-and-mouth Disease Serotype O by ELISA Using a Monoclonal Antibody

    OpenAIRE

    Chen, Hao-tai; Peng, Yun-hua; Zhang, Yong-guang; Liu, Xiang-tao

    2012-01-01

    An ELISA assay with monoclonal antibody (MELISA) was used to type serotype O of foot-and-mouth disease virus (FMDV). All FMDV serotype O reference strains were positive by MELISA, while other viruses such as FMDV serotypes Asia 1, C, and A and classical swine fever virus, swine vesicular disease virus, and porcine reproductive and respiratory syndrome virus remained negative. Furthermore, FMDV serotype O positive samples were able to be detected by MELISA. This assay may be particularly suita...

  13. A membrane-based ELISA assay for the herbicide Isoproturon in soil samples

    OpenAIRE

    Baskeyfield, Damian E. H.; Davis, Frank; Magan, Naresh; Tothill, Ibtisam E.

    2012-01-01

    A membrane based enzyme linked immunosorbent assay (MELISA) for the detection of a common herbicide, isoproturon is described. A heterogeneous competitive ELISA was the format chosen for isoproturon detection. An immunoassay system with a horseradish peroxidase (HRP) labeled polyclonal antibody preparation was developed and characterized before suitable sensitivity and selectivity for isoproturon were attained. After development as a microtiter plate immunoassay, the system was transferred to...

  14. The use of ELISAs for monitoring exposure of pig herds to Brachyspira hyodysenteriae

    Directory of Open Access Journals (Sweden)

    Song Yong

    2012-01-01

    Full Text Available Abstract Background Swine dysentery (SD, a mucohaemorrhagic diarrhoeal disease of pigs, results from infection of the large intestine with the spirochaete Brachyspira hyodysenteriae. ELISA systems using whole spirochaete cells (WC and the B. hyodysenteriae outer membrane lipoprotein Bhlp29.7 previously have been established as potential diagnostic tools for SD. However, their true value in identifying infected herds remains unclear. The present study aimed to compare the performance of whole-cell and Bhlp29.7 based ELISAs in detecting specific immunoglobulin class IgG and IgM to B. hyodysenteriae in growing pigs, and additionally evaluated whether meat juice could serve as a source of specific antibodies. Results Levels of circulating IgG and IgM reacting with WC spirochaete preparations and recombinant Bhlp29.7 peaked 4-6 weeks post-infection in the experimentally challenged pigs, and remained elevated in the present study. In a cohort of pigs on an infected farm levels of antibody directed against both antigens showed a progressive increase with time. However, other than for the level of IgG against WC antigen, a significant increase in antibody levels also was observed in a cohort of pigs on a non-infected farm. In addition, assays using meat juice had 100% specificity and equivalent sensitivity to those based on serum, and likewise the best performance was achieved using the WC IgG ELISA. Conclusions IgG ELISAs using either WC or Bhlp29.7 as plate-coating antigens were shown to be useful for monitoring the dynamics of B. hyodysenteriae infection in grower pigs. Of the two antigens, the WC preparation tended to give better discrimination between pigs from infected and non-infected farms. Testing of meat juice was shown to have potential for identifying infected herds.

  15. ELISA-seroprevalence of Toxoplasma gondii in draught horses in Greater Cairo, Egypt.

    Science.gov (United States)

    Haridy, Fouad M; Shoukry, Nahla M; Hassan, Aly Awad; Morsy, Tosson A

    2009-12-01

    Toxoplasma gondii is one of the important zoonotic parasites of worldwide. In this paper the seroprevalence of T. gondii in draught horses (3-15 years) including 90 males and 10 females in the first half of the year 2009 was studied. The result showed that the overall ELISA-T. gondii antibodies were 25% of the horses in Greater Cairo, 50% (females) and 22.2% (males).

  16. [Effect comparison between two ELISA kits in IgG antibody detection of Echinococcus granulosus].

    Science.gov (United States)

    Chu, Yan-Hong; Cai, Yu-Chun; Ai, Lin; Lu, Yan; Zhang, Jia; Chen, Jia-Xu

    2013-06-01

    To compare the effects of two ELISA kits on IgG antibody detection of human Echinococcus granulosus. A Total of 134 sera of patients with echinococcosis, paragonimiasis westermani, clonorchiasis sinensis, schistosomiasis japonica, and cysticercosis cellulosae, and normal persons were detected by two IgG ELISA kits produced by different companies. Furthermore, the specificity, sensitivity and cross reactivity were counted and analyzed statistically. The sensitivity and specificity were extremely high of the two kits as 100.00%. The cross-reactivity rates were 25.00% (paragonimiasis westermani), 26.09% (clonorchiasis sinensis), 10.00% (schistosomiasis japonica), and 87.5% (cysticercosis), respectively, by using the kit produced by the Combined Company in Shenzhen; the cross-reactivity rates were 5.00% (paragonimiasis westermani), 13.04% (clonorchiasis sinensis), 20.00% (schistosomiasis japonica), and 93.75% (cysticercosis) respectively, by using the kit produced by Haitai Company in Zhuhai. In addition, there was a significant difference of Paragonimus westermani detection (P 0.05) between the two kits. Both ELISA kits on IgG antibody detection of human Echinococcus granulosus have the advantages of a high sensitivity, specificity, convenience and high-speed. However, it is also in urgent need to further solve the cross-reactivity of Echinococcus granulosus with other parasites, in order to improve the accuracy of early diagnosis.

  17. Comparison between mixed lysate antigen and α-actinin antigen in ELISA for serodiagnosis of trichomoniasis.

    Science.gov (United States)

    Kim, Seung-Ryong; Kim, Jung-Hyun; Park, Soon-Jung; Lee, Hye-Yeon; Kim, Yong-Suk; Kim, Yu-Mi; Hong, Yeon-Chul; Ryu, Jae-Sook

    2015-10-01

    The aim of this study was to identify an antigen suitable for ELISA for serodiagnosis of Trichomonas vaginalis (T. vaginalis) infection. Mixed lysate antigen (Ag) from eight strains of T. vaginalis and recombinant α-actinin protein was compared. The sera of three groups were examined by ELISA: 73 women infected with trichomoniasis served as a positive control, 31 male volunteers as a negative control, and 424 women attending an outpatient health screening at Hanyang University Guri Hospital. Based on the cutoff optical density for each Ag obtained with a negative control, the serosensitivity of the mixed lysate Ag (79.5%) was significantly higher than that of the α-actinin (52.1%) in the 73 patients with trichomoniasis. The specificity using lysate Ag and α-actinin was 100% and 96.8%, respectively. On the other hand, the positivity rate in 424 outpatients was 39.2% and 11.8% with mixed lysate and α-actinin Ag, respectively. Taken together, mixed lysate Ag showed higher sensitivity and specificity than α-actinin. Therefore, mixed lysate may be a better Ag than α-actinin for ELISA for the diagnosis of trichomoniasis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  18. Implementation and Setup of a System Dedicated Logbook based on ELisA

    CERN Document Server

    Van Tonder, Raynette

    2016-01-01

    ELisA is a web tool used by the ATLAS community as a daily logbook facility in order to record and share information concerning the experiment's operation and deployment. A few subsystems, notably the FTK subsystem, of the ATLAS experiment would like to setup a logbook based on the ELisA logbook for their own private usage. This new logbook would be completely separated from the main ATLAS logbook and will only be accessed from the general public network. In this project the implementation and setup of the ELisA based logbook will be discussed as well as various modifications that were made to the new logbook. These modifications were specified by the FTK users in order to make the logbook relevant to the FTK subsystem. Once the logbook was functioning as expected and the users were satisfied with the modifications, the FTK logbook was installed on a FTK dedicated machine where it is currently being used by members of the FTK group.

  19. Comparison of the sensitivity of determining soyeabean allergens by ELISA method and SYBR green I

    Directory of Open Access Journals (Sweden)

    Jozef Golian

    2013-07-01

    Full Text Available Normal 0 false false false SK JA X-NONE The aim of this study was to compare the suitability of two methods for detecting defatted soybean powder; SYBR Green I Real-time PCR and enzyme-linked immunosorbent assay (ELISA. Analysis of 20 artificially contaminated samples prepared by simple dilution with wheat flour revealed that both techniques were able to detect defatted soybean powder, although there were significant differences between the two methods. Wheat flour contamination with defatted soybean powder was detected in samples 1-5, (0.012 %; 120 mg.kg-1, but not in samples with lower contamination with soybean powder saples 6-20 using SYBR Green I real-time PCR. Samples 1-10 could not be quantified by ELISA as the absorbance values were greater than the detection limit, and while samples 11-20 were measured, only the values of samples 16, 17 and 18 were within the guaranteed quantification range specified by the ELISA kit manufacturer. Defatted soybean powder contamination was detected in samples 19 and 20, but absorbance values were highly similar to those of the negative control sample.

  20. Development of an ELISA and Immunochromatographic Strip for Highly Sensitive Detection of Microcystin-LR

    Directory of Open Access Journals (Sweden)

    Liqiang Liu

    2014-08-01

    Full Text Available A monoclonal antibody for microcystin–leucine–arginine (MC-LR was produced by cell fusion. The immunogen was synthesized in two steps. First, ovalbumin/ bovine serum albumin was conjugated with 6-acetylthiohexanoic acid using a carbodiimide EDC (1-ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride/ NHS (N-hydroxysulfosuccinimide reaction. After dialysis, the protein was reacted with MC-LR based on a free radical reaction under basic solution conditions. The protein conjugate was used for immunization based on low volume. The antibodies were identified by indirect competitive (icELISA and were subjected to tap water and lake water analysis. The concentration causing 50% inhibition of binding of MC-LR (IC50 by the competitive indirect ELISA was 0.27 ng/mL. Cross-reactivity to the MC-RR, MC-YR and MC-WR was good. The tap water and lake water matrices had no effect on the detection limit. The analytical recovery of MC-LR in the water samples in the icELISA was 94%–110%. Based on this antibody, an immunochromatographic biosensor was developed with a cut-off value of 1 ng/mL, which could satisfy the requirement of the World Health Organization for MC-LR detection in drinking water. This biosensor could be therefore be used as a fast screening tool in the field detection of MC-LR.

  1. Biomimetic ELISA detection of malachite green based on magnetic molecularly imprinted polymers.

    Science.gov (United States)

    Li, Lu; Lin, Zheng-Zhong; Peng, Ai-Hong; Zhong, Hui-Ping; Chen, Xiao-Mei; Huang, Zhi-Yong

    2016-11-01

    A direct competitive enzyme-linked immunosorbent assay (ELISA) method was used for the detection of malachite green (MG) with a high sensitivity and selectivity using magnetic molecularly imprinted polymers (MMIPs) as a bionic antibody. MMIPs were prepared through emulsion polymerization using Fe 3 O 4 nanoparticles as magnetic nuclei, MG as a template, methacrylic acid (MAA) as a functional monomer, ethylene glycol dimethacrylate (EGDMA) as a crosslinking agent and span-80/tween-80 as mixed emulsifiers. The MMIPs were characterized by scanning electron micrographs (SEM), thermal-gravimetric analyzer (TGA), Fourier transform infrared spectrometer (FT-IR) and vibrating sample magnetometer (VSM), respectively. A high magnetic saturation value of 54.1emug -1 was obtained, resulting in rapid magnetic separation of MMIPs with an external magnet. The IC 50 of the established ELISA method was 20.1μgL -1 and the detection limit (based on IC 85 ) was 0.1μgL -1 . The MMIPs exhibited high selective binding capacity for MG with cross-reactivities less than 3.9% for MG structural analogues. The MG spiking recoveries were 85.0%-106% with the relative standard deviations less than 4.7%. The results showed that the biomimetic ELISA method by using MMIPs as bionic antibody could be used to detect MG rapidly in fish samples with a high sensitivity and accuracy. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. DETECTION OF HUMAN BLOODSTAINS BY ENZYME-LINKED IMMUNOSORBENT ASSAY (ELISA

    Directory of Open Access Journals (Sweden)

    GHOLAM-HOSSEIN EDRISSIAN

    1982-07-01

    Full Text Available The microplate method of e nzyme-l i nke d i rnmuno s o r be n t a s s ay (ELISA , usi ng alkaline phosphatase anti-human I gG conj ugate , was modified and appl ied in t he dete c t i on of the human b lood specimens among the blood samples prep a r ed fr om human and laborat or y anima l s i n t he form of small dr ied b loodst a i ns on f ilt e r paper . The modi f i e d ELISA t e chnique wa s compa red wit h t he agar double d i f f us ion me t hod of prec ipitin test ."nThe results of this primary study showed t ha t the ELISA i n compare to gel diffusi o n t e st is sensitive and specific. It is also enough repr oducible and practical t o be consider as a competent technique for i de nt i f i c ation o f human bloodstains in medicolegal laboratories .

  3. HPLC and ELISA analyses of larval bile acids from Pacific and western brook lampreys

    Science.gov (United States)

    Yun, S.-S.; Scott, A.P.; Bayer, J.M.; Seelye, J.G.; Close, D.A.; Li, W.

    2003-01-01

    Comparative studies were performed on two native lamprey species, Pacific lamprey (Lampetra tridentata) and western brook lamprey (Lampetra richardsoni) from the Pacific coast along with sea lamprey (Petromyzon marinus) from the Great Lakes, to investigate their bile acid production and release. HPLC and ELISA analyses of the gall bladders and liver extract revealed that the major bile acid compound from Pacific and western brook larval lampreys was petromyzonol sulfate (PZS), previously identified as a migratory pheromone in larval sea lamprey. An ELISA for PZS has been developed in a working range of 20pg-10ng per well. The tissue concentrations of PZS in gall bladder were 127.40, 145.86, and 276.96??g/g body mass in sea lamprey, Pacific lamprey, and western brook lamprey, respectively. Releasing rates for PZS in the three species were measured using ELISA to find that western brook and sea lamprey released PZS 20 times higher than Pacific lamprey did. Further studies are required to determine whether PZS is a chemical cue in Pacific and western brook lampreys. ?? 2003 Elsevier Inc. All rights reserved.

  4. Low-Frequency Gravitational-Wave Science with eLISA/ NGO

    Science.gov (United States)

    Amaro-Seoane, Pau; Aoudia, Sofiane; Babak, Stanislav; Binetruy, Pierre; Berti, Emanuele; Bohe, Alejandro; Caprini, Chiara; Colpi, Monica; Cornish, Neil J.; Danzmann, Karsten; hide

    2011-01-01

    We review the expected science performance of the New Gravitational-Wave Observatory (NGO, a.k.a. eLISA), a mission under study by the European Space Agency for launch in the early 2020s. eLISA will survey the low-frequency gravitational-wave sky (from 0.1 mHz to 1 Hz), detecting and characterizing a broad variety of systems and events throughout the Universe, including the coalescences of massive black holes brought together by galaxy mergers; the inspirals of stellar-mass black holes and compact stars into central galactic black holes; several millions of ultracompact binaries, both detached and mass transferring, in the Galaxy; and possibly unforeseen sources such as the relic gravitational-wave radiation from the early Universe. eLISA's high signal-to-noise measurements will provide new insight into the structure and history of the Universe, and they will test general relativity in its strong-field dynamical regime.

  5. Detection of pregnancy in sheep using an ELISA for pregnancy-specific protein B.

    Science.gov (United States)

    Milisits-Németh, Tímea; Balogh, Orsolya Gabriella; Egerszegi, István; Kern, László; Sasser, R Garth; Gábor, György

    2018-06-01

    The early detection of pregnancy and the determination of fetal numbers have economic benefits in sheep production because of the seasonal breeding patterns where missing a breeding opportunity means the loss of one productive year. The purpose of this study was to evaluate the efficacy of the B6-HRP ELISA for ovine pregnancy-specific protein B (oPSPB) measurement in the detection of pregnancy and estimation of fetal numbers in different sheep breeds. BioPRYN® ELISA assay kit was used for the detection of pregnancy in the experimental animals. Ninety-three ewes of three breeds (British Milksheep - BM, Lacaune - L and Transylvanian Racka - TR), each from three farms in Hungary, were included in the study. BM and L ewes were artificially inseminated (AI). Thirty-five days after AI, all ewes were examined by transabdominal ultrasound. The TR flock was mated naturally over a six-week period. At the end of the mating period, the ewes were similarly examined by ultrasound. Blood samples were taken from all pregnant ewes twice (35 and 65 days after AI), and serum samples were assayed by the BioPRYN test. It can be concluded that the detection of serum PSPB by ELISA is a much easier, safer, less expensive and highly accurate method for the detection of ovine pregnancy. Although some breed-related differences were detectable at 35 and 65 days post breeding, no differences in oPSPB levels were found in pregnant ewes carrying different numbers of fetuses.

  6. Comparison of ELISA, radioimmunoassay and stool examination for Schistosoma mansoni infection

    Energy Technology Data Exchange (ETDEWEB)

    Long, E G [Ministry of Health, St. Lucia (West Indies); McLaren, M M; Goddard, M J [London School of Hygiene and Tropical Medicine (UK); Bartholomew, R K; Goodgame, R [Rockefeller Foundation, New York (USA); Peters, P [Case Western Reserve Univ., Cleveland, OH (USA)

    1981-01-01

    A comparison was made of the sensitivity and specificity of four diagnostic tests for Schistosoma mansoni infection in a community of 516 untreated persons in St. Lucia, West Indies. Prevalence of infection as obtained by: (i) the Bell filtration technique was 44.4% (one filter) and 63.2% (three filters); (ii) the Kato thick smear, 60.2%; (iii) by radioimmunoassay (RIA), using /sup 125/I, 73.3%; and (iv) enzyme-immunoassay (ELISA) 70.9%. The age distribution of persons serologically positive but parasitologically negative showed these to be mostly children and persons 40 years old and over. By means of a statistical test due to Cochrane it was concluded that there was no evidence to indicate a difference between paired serological tests and paired parasitological tests in their diagnostic capability. There was a very significant difference between the Bell technique and the other three tests. The ELISA emerged as a less satisfactory test than the RIA or the Kato thick smear. The levels of sensitivity and specificity of each test were measured by Armitage's ''J'' index. The reliability of the Bell filtration technique was 64%, of the ELISA 68%, of the RIA 78% and of the Kato 85%.

  7. Selectivity verification of cardiac troponin monoclonal antibodies for cardiac troponin detection by using conventional ELISA

    Science.gov (United States)

    Fathil, M. F. M.; Arshad, M. K. Md; Gopinath, Subash C. B.; Adzhri, R.; Ruslinda, A. R.; Hashim, U.

    2017-03-01

    This paper presents preparation and characterization of conventional enzyme-linked immunosorbent assay (ELISA) for cardiac troponin detection to determine the selectivity of the cardiac troponin monoclonal antibodies. Monoclonal antibodies, used to capture and bind the targets in this experiment, are cTnI monoclonal antibody (MAb-cTnI) and cTnT monoclonal antibody (MAb-cTnT), while both cardiac troponin I (cTnI) and T (cTnT) are used as targets. ELISA is performed inside two microtiter plates for MAb-cTnI and MAb-cTnT. For each plate, monoclonal antibodies are tested by various concentrations of cTnI and cTnT ranging from 0-6400 µg/l. The binding selectivity and level of detection between monoclonal antibodies and antigen are determined through visual observation based on the color change inside each well on the plate. ELISA reader is further used to quantitatively measured the optical density of the color changes, thus produced more accurate reading. The results from this experiment are utilized to justify the use of these monoclonal antibodies as bio-receptors for cardiac troponin detection by using field-effect transistor (FET)-based biosensors coupled with substrate-gate in the future.

  8. Development of monoclonal antibody-based sandwich ELISA for detection of dextran.

    Science.gov (United States)

    Wang, Sheng-Yu; Li, Zhe; Wang, Xian-Jiang; Lv, Sha; Yang, Yun; Zeng, Lian-Qiang; Luo, Fang-Hong; Yan, Jiang-Hua; Liang, Da-Feng

    2014-10-01

    Dextran as anti-nutritional factor is usually a result of bacteria activity and has associated serial problems during the process stream in the sugar industry and in medical therapy. A sensitive method is expected to detect dextran quantitatively. Here we generated four monoclonal antibodies (MAbs) against dextran using dextran T40 conjugated with bovine serum albumin (BSA) as immunogen in our lab following hybridoma protocol. Through pairwise, an MAb named D24 was determined to be conjugated with horseradish peroxidase (HRP) and was used in the establishment of a sensitive sandwich enzyme-linked immunosorbent assay (ELISA) method for determination of dextran, in which MAb D9 was chosen as a capture antibody. The detection limit and working scope of the developed sandwich ELISA method were 3.9 ng/mL and 7.8-500 ng/mL with a correlation coefficient of 0.9909. In addition, the cross-reaction assay demonstrated that the method possessed high specificity with no significant cross-reaction with dextran-related substances, and the recovery rate ranged from 96.35 to 102.00%, with coefficient of variation ranging from 1.58 to 6.94%. These results indicated that we developed a detection system of MAb-based sandwich ELISA to measure dextran and this system should be a potential tool to determine dextran levels.

  9. Development of an ELISA for evaluation of swab recovery efficiencies of bovine serum albumin.

    Directory of Open Access Journals (Sweden)

    Nadja Sparding

    Full Text Available After a potential biological incident the sampling strategy and sample analysis are crucial for the outcome of the investigation and identification. In this study, we have developed a simple sandwich ELISA based on commercial components to quantify BSA (used as a surrogate for ricin with a detection range of 1.32-80 ng/mL. We used the ELISA to evaluate different protein swabbing procedures (swabbing techniques and after-swabbing treatments for two swab types: a cotton gauze swab and a flocked nylon swab. The optimal swabbing procedure for each swab type was used to obtain recovery efficiencies from different surface materials. The surface recoveries using the optimal swabbing procedure ranged from 0-60% and were significantly higher from nonporous surfaces compared to porous surfaces. In conclusion, this study presents a swabbing procedure evaluation and a simple BSA ELISA based on commercial components, which are easy to perform in a laboratory with basic facilities. The data indicate that different swabbing procedures were optimal for each of the tested swab types, and the particular swab preference depends on the surface material to be swabbed.

  10. Detection of tetracosactide in plasma by enzyme-linked immunosorbent assay (ELISA).

    Science.gov (United States)

    Martin, Laurent; Chaabo, Ayman; Lasne, Françoise

    2015-06-01

    As a synthetic analogue of adrenocorticotropic hormone (ACTH), tetracosactide is prohibited in sport by the World Anti-Doping Agency (WADA). An enzyme-linked immunosorbent assay (ELISA) method is proposed for detection of this drug in plasma. Since its structure corresponds to the 24 N-terminal of the 39 amino acids of the natural endogenous peptide ACTH, tetracosactide can be detected with a commercial ELISA kit for ACTH that uses antibodies, the epitopes of which are located in the 1-24 part of ACTH. However, an essential condition for detection specificity is the preliminary total clearance of endogenous ACTH in the plasma samples. This is achieved by a preparative step based on cation-exchange chromatography before ELISA. The method is specific and sensitive (LOD: 30 pg/mL) and may be used as a screening analysis in anti-doping control. The pre-analytical conditions are shown to be of the upmost importance and recommendations for blood collection (EDTA tubes), sample transport (4 °C) and plasma sample storage (-20 °C) are presented. Copyright © 2014 John Wiley & Sons, Ltd.

  11. Merozoite proteins from Babesia sp. BQ1 (Lintan) as potential antigens for serodiagnosis by ELISA.

    Science.gov (United States)

    Guan, G Q; Chauvin, A; Rogniaux, H; Luo, J X; Yin, H; Moreau, E

    2010-05-01

    Babesia sp. BQ1 (Lintan) is a Babesia isolated from sheep infested with Haemaphysalis qinghaiensis in China, and is closely related to B. motasi based on the 18S rRNA gene sequence. In the present study, an ELISA was developed with merozoite antigens of Babesia sp. BQ1 (Lintan) (BQMA) purified from in vitro culture. When the positive threshold was chosen as 30% of the antibodies rate, evaluated with 198 negative sera, the specificity was 95.5%. Except for Babesia sp. Tianzhu, there was no cross-reaction between BQMA and positive sera from Babesia sp. BQ1 (Ningxian)-, Babesia sp. Hebei-, Babesia sp. Xinjiang-, Theileria luwenshuni-, T. uilenbergi-, or Anaplasma ovis-infected sheep, which are the dominant haemoparasites of small ruminants in China. Specific antibodies against Babesia sp. BQ1 (Lintan) were produced 1 or 2 weeks post-infection and a high level of antibodies persisted for more than 8 months in experimentally infected sheep. This ELISA was tested on 974 sera collected from field-grazing sheep in 3 counties of Gansu province, northwestern China to evaluate the seroprevalence of Babesia sp. BQ1 (Lintan) infection and the average positive rate was 66.84%. The feasibility of increasing the specificity of this BQMA-based ELISA, by using some BQMA antigens for serodiagnosis is discussed.

  12. Immunoprecipitation techniques and Elisa in the detection of anti-Fonsecaea pedrosoi antibodies in chromoblastomycosis

    Directory of Open Access Journals (Sweden)

    Vidal Mônica Scarpelli Martinelli

    2003-01-01

    Full Text Available Chromoblastomycosis (CBM is a chronic subcutaneous infection caused by several dematiaceous fungi. The most commonly etiological agent found in Brazil is Fonsecaea pedrosoi, which appears as thick walled, brownish colored cells with transverse and longitudinal division in the lesions, called "muriform cells". This disease is found worldwide but countries like Madagascar and Brazil have highest incidence. Diagnosis is made by clinical, direct and histopathologic examination and culture of specimens. Serological tests have been used to identify specific antibodies against Fonsecaea pedrosoi antigens, as well as immunotechniques have been used for CBM serological identification and diagnosis. In the present study double immunodiffusion (DID, counterimmunoelectrophoresis (CIE and immunoenzymatic test (ELISA have been used to evaluate humoral immune response in patients with CBM caused by F. pedrosoi. Metabolic antigen was used for immunoprecipitation tests (DID and CIE while somatic antigen for ELISA. Our results demonstrated 53% sensitivity and 96% specificity for DID, while CIE presented 68% sensitivity and 90.5% specificity. ELISA demonstrated 78% sensibility and 83% specificity. Serological tests can be a useful tool to study different aspects of CBM, such as helping differential diagnosis, when culture of the pathogenic agent is impossible.

  13. Outstanding insecurities concerning the use of an Ov16-based ELISA in the Amazonia onchocerciasis focus

    Directory of Open Access Journals (Sweden)

    Sérgio Luiz Bessa Luz

    2014-07-01

    Full Text Available In a recent issue of Memórias do Instituto Oswaldo Cruz, published in Rio de Janeiro in February 2014 (109: 87-92, Adami et al. have published a survey reporting Mansonella parasite prevalence in the Amazon Region. This report makes a useful contribution to the existing knowledge of filarial parasite distribution within the Amazon area, parasite prevalence rates in relation to age and occupation and provides observations on the possible clinical impact of Mansonella ozzardi. Their publication also provides an account of what appears to be a novel ELISA that has recently been used in the Simuliidae and Onchocerciasis Laboratory of the Oswaldo Cruz Institute, Rio de Janeiro, Brazil. We are concerned that the publication of this ELISA may have created an excessively positive impression of the effectiveness of the onchocerciasis recrudescence serological surveillance tools that are presently available for use in the Amazonia onchocerciasis focus. In this letter we have, thus, sought to highlight some of the limitations of this ELISA and suggest how continuing insecurities concerning the detection of antibodies to Onchocerca volvulus within the Amazonia onchocerciasis focus might be minimised.

  14. Transferability of antibody pairs from ELISA to fiber optic surface plasmon resonance for infliximab detection

    Science.gov (United States)

    Van Stappen, Thomas; Lu, Jiadi; Bloemen, Maarten; Geukens, Nick; Spasic, Dragana; Delport, Filip; Verbiest, Thierry; Lammertyn, Jeroen; Gils, Ann

    2015-03-01

    Tumor necrosis factor (TNF)-alpha is a pleiotropic cytokine up-regulated in inflammatory bowel disease, rheumatoid arthritis and psoriasis. The introduction of anti-TNF drugs such as infliximab has revolutionized the treatment of these diseases. Recently, therapeutic drug monitoring (TDM) of infliximab has been introduced in clinical decision making to increase cost-efficiency. Nowadays, TDM is performed using radio-immunoassays, homogeneous mobility shift assays or ELISA. Unfortunately, these assays do not allow for in situ treatment optimization, because of the required sample transportation to centralized laboratories and the subsequent assay execution time. In this perspective, we evaluated the potential of fiber optic-surface plasmon resonance (FO-SPR). To achieve this goal, a panel of 55 monoclonal anti-infliximab antibodies (MA-IFX) was developed and characterized in-house, leading to the identification of nine different clusters. Based on this high diversity, 22 antibody pairs were selected and tested for their reactivity towards IFX, using one MA-IFX as capture and one MA-IFX for detection, in a sandwich type ELISA and FO-SPR. This study showed that the reactivity towards IFX of each antibody pair in ELISA is highly similar to its reactivity on FO-SPR, indicating that antibody pairs are easily transferable between both platforms. Given the fact that FO-SPR shows the potential for miniaturization and fast assay time, it can be considered a highly promising platform for on-site infliximab monitoring.

  15. Las cosas por su nombre

    OpenAIRE

    Storani, Emilia

    2017-01-01

    El artículo propone indagar sobre los modos y diferentes formatos que se utilizan tanto en la escritura como en la lectura, para articular con las luchas por la identidad de género. La Ley de Identidad de Género ha sido un puntapié clave para pensarnos a nosotros mismos culturalmente y para pensar a los demás. Pero, ¿cómo mencionamos, escribimos y leemos las diferentes identidades? La escritura, también es un mundo transformador para quienes bregan por una sociedad más libre y sin prejuicios....

  16. Ptose palpebral causada por Paquidermoperiostose

    Directory of Open Access Journals (Sweden)

    Patricia Regina de Pinho Tavares

    2014-08-01

    Full Text Available A paquidermoperiostose é uma síndrome caracterizada por acometimento cutâneo e ósseo, e em alguns casos ocorre comprometimento palpebral leve. É uma síndrome rara, idiopática ou hereditária, com provável herança autossômica dominante de penetrância variável. Descreve-se o caso de um paciente com ptose grave por paquidermoperiostose elucidando sua fisiopatologia e conduta cirúrgica aplicada.

  17. Diverticulitis yeyunal perforada por enterolito.

    OpenAIRE

    Marenco De la Cuadra, Beatriz; Gomez-Rosado, Juan-Carlos; Capitan-Morales, Luis-Cristobal; Valdés Hernández, Javier; Reyes-lopera, N.J. De los

    2012-01-01

    La diverticulosis yeyunal es una enfermedad adquirida rara. Casi el 60-70% keeps asymptomátic or Con síntomas crónicos inespecíficos, aunque puede presentarse como un abdomen agudo. La perforación debida a enterolitos es una causa extremadamente rara do complicación, y puede producirse por la impactación de ésta contra la pared intestinal. Presentamos caso de un varón de 82 años que acude a urgencias por un dolor súbito abdominal, difuso, con irritación peritoneal, leucocitosis con neutro...

  18. Mortalidad intrahospitalaria por accidente cerebrovascular

    OpenAIRE

    Federico Rodríguez Lucci; Virginia Pujol Lereis; Sebastián Ameriso; Guillermo Povedano; María F. Díaz; Alejandro Hlavnicka; Néstor A. Wainsztein; Sebastián F. Ameriso

    2013-01-01

    La mortalidad global por accidente cerebrovascular (ACV) ha disminuido en las últimas tres décadas, probablemente debido a un mejor control de los factores de riesgo vascular. La mortalidad hospitalaria por ACV ha sido tradicionalmente estimada entre 6 y 14% en la mayoría de las series comunicadas. Sin embargo, los datos de ensayos clínicos recientes sugieren que esta cifra sería sustancialmente menor. Se revisaron datos de pacientes internados con diagnóstico de ACV del Banco de Datos de Str...

  19. Development and Evaluation of a Novel ELISA for Detection of Antibodies against HTLV-I Using Chimeric Peptides.

    Science.gov (United States)

    Mosadeghi, Parvin; Heydari-Zarnagh, Hafez

    2018-04-01

    We aimed to develope a peptide-based indirect ELISA to detect antibodies against Human T-lymphotropic virus type I (HTLV-I). Two chimeric peptides (CP-1 and CP-2) were designed using linear immunodominant epitopes of gp-46-I, and gp21-I proteins, according to the sequence from Uniprot database. These peptides were studied initially in the ELISA using infected sera. The most promising peptideCP-1, was used to develop a peptide ELISA for detection of HTLV-I infected sera. The optimal conditions for CP-1ELISA were: the optimum coating buffer was 100mM NaHCO3, pH 9.6; coating peptide concentration was 10 µg/mL; the optimal blocking buffer was5% fetal bovine serum (FBS); the secondary antibody concentration was 1:2000; and serum dilution was 1:20. 20serum samples from HTLV-I infected patients were evaluated by ELISA developed. CP-1 showed high antigenicity while lacking any cross-reactivity with normal human sera. The results of evaluations indicated that in comparison with commercial ELISA, CP-1 ELISA showed good sensitivity and specificity. With further validation, CP-1as described in the present study could be introduced as novel reliable and cost-effective candidates for the high-specific screening of HTLV-I/-II infections in endemic regions.

  20. Immune response to Mycoplasma pneumoniae P1 and P116 in patients with atypical pneumonia analyzed by ELISA

    Directory of Open Access Journals (Sweden)

    Birkelund Svend

    2004-02-01

    Full Text Available Abstract Background Serology is often used for the diagnosis of Mycoplasma pneumoniae. It is important to identify specific antigens that can distinguish between the presence or absence of antibodies against M. pneumoniae. The two proteins, P116 and P1, are found to be immunogenic. By using these in ELISA it is possible to identify an immune response against M. pneumoniae in serum samples. Results A recombinant protein derived from the P116 protein and one from the P1 protein were used in two ELISA tests, rP116-ELISA and rP1-ELISA. Human serum samples from patients with atypical pneumonia were tested and compared to the results of the complement fixation test. There was a good agreement between the two tests but the rP1-ELISA showed the best discrimination between positive and negative samples. Conclusion Two ELISA tests based on recombinant proteins have been analysed and compared to the complement fixation test results. The two ELISA tests were found suitable for use in serodiagnostics of M. pneumoniae infections. The use of specific antigens eliminates the risk of cross reaction to an immune response against other bacteria.

  1. Detection of Trypanosoma congolense type savannah in field samples of buffy coats of bovins using PCR-ELISA

    International Nuclear Information System (INIS)

    Sidibe, I.

    2007-01-01

    PCR-ELISA was set up to detect strain of Trypanosoma congolense type savannah in field samples of buffy coats. Results of PCR-ELISA and PCR were compared and the sensibility and specificity of both techniques were also compared with those of the method of Murray [1] for the detection of TCS in 257 samples. The PCR products were labelling with DIG-dUTP during amplification cycles of the repetitive satellite DNA. A DNA biotinyled capture probe was used to detect the amplicon by ELISA in streptavidine coated microplates. Both of PCR-ELISA and PCR were more sensible and more specific than the method of Murray. Indeed, for the 257 samples analysed by the three techniques, PCR-ELISA and PCR have detected TCS in 98 and 97 samples respectively, whereas the method of Murray has detected TCS in only 39 samples. In addition, PCRELISA and PCR had almost the same sensibility and specificity. So, PCR-ELISA and PCR have respectively detected TCS in 38.62% and 39.22% of all the 334 samples analysed by both techniques during this study. At the end of this study, the cost of analyse by PCR-ELISA of a sample of buffy coat, was evaluated at 1993 FCFA or Euro 3,04. (author) [fr

  2. 2004 National Atrazine Occurrence Monitoring Program using the Abraxis ELISA method.

    Science.gov (United States)

    Graziano, Nicole; McGuire, Michael J; Roberson, Alan; Adams, Craig; Jiang, Hua; Blute, Nicole

    2006-02-15

    The goal of this project was to gain a better understanding of atrazine occurrence in the United States by surveying drinking water utilities' sources and finished water for atrazine on a weekly basis for seven months. Atrazine is a contaminant of interest because the United States Environmental Protection Agency (USEPA) has found short-term atrazine exposure above the drinking water maximum contaminant level (MCL) to potentially cause heart, lung, and kidney congestion, low blood pressure, muscle spasms, weight loss, and damage to the adrenal glands. Long-term exposure to atrazine concentrations above the drinking water MCL has been linked to weight loss, cardiovascular damage, retinal and muscle degeneration, and cancer. This survey effort improved upon previously conducted atrazine surveys through intensive, high frequency sampling (participating plants sampled their raw and finished water on a weekly basis for approximately seven months). Such an intensive effort allowed the authors to gain a better understanding of short-term atrazine occurrence and its variability in drinking water sources. This information can benefit the drinking water industry by facilitating (1) better atrazine occurrence management (i.e., awareness when plants may be more susceptible to atrazine), (2) more efficient atrazine control (e.g., effective treatment alternatives and more effective response to atrazine occurrence), and (3) treatment cost reduction (e.g., efficient atrazine control can result in substantial cost savings). Forty-seven drinking watertreatment plants located primarily in the Midwestern United States participated in the survey and sampled their raw and finished water on a weekly basis from March through October. Samples were analyzed using the Abraxis enzyme-linked immunosorbent assay (ELISA) test kit. Confirmation samples for quality assurance/quality control (QA/QC) purposes were analyzed using solid-phase extraction (SPE) followed by gas chromatography mass

  3. Elisa for the diagnosis and epidemiology of Brucella abortus infection in cattle in Chile

    International Nuclear Information System (INIS)

    Rojas, X.; Alonso, O.

    1998-01-01

    A serum bank of 1251 adult cows sera was prepared. The sera originated from animals of three different epidemiological groups: 1) 244 from infected cows, strain 19 vaccinated when calves; 2) 507 from herds free of infection but all cows were strain 19 vaccinated when calves and 3) the last group, 500 sera from cows free of infection and non-vaccinated. All the sera where tested with the routine Rose Bengal (RB) Rivanol (RIV) and Complement Fixation (CF) tests and additionally three enzyme immunoassays were performed. They included two indirect Elisa both using the kit from the Joint FAO/IAEA Division, Vienna, Austria. One assay used a polyclonal conjugated antibody (I-ELISAp) and the other a monoclonal conjugated antibody (I-ELISAm). The third assay was a competitive ELISA (C-ELISA) performed with sLPS, plus monoclonal antibody, M84, and goat anti-mouse antibody-HRPO. Using the CFT as 'gold standard' the sensitivities of all the methods were: RB 87.1%, RIV 87.1%, I-ELISAp 100% I-ELISAm 100%. The calculated specificity was: RB 100%, RIV 100%, I-ELISAp 96.4% and I-ELISAm 100%. In the group of infected animals (244) the following results were obtained: RB 13.5%, RIV 11.9%, CF 12.7%, I-ELISAp 50.8% and I-ELISAm 22.9%. Results for the non-vaccinated group were: RB 0.2%, RIV 0%, CFT 0.2%, I-ELISAp 6.9% and I-ELISAm 2.9%. The C-ELISA was performed on samples from the positive group or with positivity values close to the cut-off value in the I-ELISAm. In the infected group 28 out of 63 animals were detected as infected and from the non-vaccinated herds none of 15 I-ELISAm positive samples were detected as infected in the C-ELISA. (author)

  4. Doing Science with eLISA: Astrophysics and Cosmology in the Millihertz Regime

    Science.gov (United States)

    Amaro, Seoane, Pau; Aoudia, Sofiane; Babak, Stanislav; Binetruy, Pierre; Berti, Amanuele; Bohe, Alejandro; Caprini, Chiara; Colpi, Monica; Cornish, Neil J.; Danzmann, Karsten; hide

    2012-01-01

    This document introduces the exciting and fundamentally new science and astronomy that the European New Gravitational Wave Observatory (NGO) mission (derived from the previous LISA proposal) will deliver. The mission (which we will refer to by its informal name eLISA ) will survey for the first time the low-frequency gravitational wave band (about 0.1 mHz to 1 Hz), with sufficient sensitivity to detect interesting individual astrophysical sources out to z = 15. The measurements described here will address the basic scientific goals that have been captured in ESA s New Gravitational Wave Observatory Science Requirements Document ; they are presented here so that the wider scientific community can have access to them. The eLISA mission will discover and study a variety of cosmic events and systems with high sensitivity: coalescences of massive black holes binaries, brought together by galaxy mergers; mergers of earlier, less-massive black holes during the epoch of hierarchical galaxy and black-hole growth; stellar-mass black holes and compact stars in orbits just skimming the horizons of massive black holes in galactic nuclei of the present era; extremely compact white dwarf binaries in our Galaxy, a rich source of information about binary evolution and about future Type Ia supernovae; and possibly most interesting of all, the uncertain and unpredicted sources, for example relics of inflation and of the symmetry-breaking epoch directly after the Big Bang. eLISA s measurements will allow detailed studies of these signals with high signal-to-noise ratio, addressing most of the key scientific questions raised by ESA s Cosmic Vision programme in the areas of astrophysics and cosmology. They will also provide stringent tests of general relativity in the strong-field dynamical regime, which cannot be probed in any other way. This document not only describes the science but also gives an overview on the mission design and orbits. LISA s heritage in the eLISA design will be

  5. Influence of clinical and laboratory variables on faecal antigen ELISA results in dogs with canine parvovirus infection.

    Science.gov (United States)

    Proksch, A L; Unterer, S; Speck, S; Truyen, U; Hartmann, K

    2015-06-01

    False negative faecal canine parvovirus (CPV) antigen ELISA results in dogs with CPV infection are common, but the factors that lead to these false negative results are still unknown. The aim of this study was to investigate whether dogs with a false negative faecal CPV antigen ELISA result have milder clinical signs and laboratory changes, a lower faecal virus load, higher faecal and serum CPV antibody titres and a faster recovery than dogs with a positive result. Eighty dogs with CPV infection, confirmed by the presence of clinical signs and a positive faecal CPV polymerase chain reaction (PCR), were assigned to two groups according to their faecal antigen ELISA result. Time until presentation, severity of symptoms, laboratory parameters, faecal virus load, faecal and serum antibody titres, and CPV sequencing data were compared between both groups. In 38/80 dogs that were hospitalised until recovery, the time to recovery, mortality, and the course of the disease were compared between dogs with positive and negative faecal antigen ELISA results. Of the 80 dogs included, 41 (51.3%) had a false negative faecal antigen ELISA result. ELISA-negative dogs had a significantly shorter time until presentation, lower frequency of defaecation, lower faecal virus load, and higher serum antibody concentrations than ELISA-positive dogs. Laboratory changes, CPV shedding, and outcomes were not associated with faecal antigen ELISA results. In conclusion, low faecal CPV load and antibodies binding to CPV antigen in faeces are likely to be important reasons for false negative faecal antigen ELISA results. Dogs with clinical signs of CPV infection should be retested by faecal PCR. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Evaluation of two commercially available ELISA kits for the determination of melatonin concentrations in amniotic fluid throughout pregnancy.

    Science.gov (United States)

    Bagci, Soyhan; Altuntas, Özlem; Katzer, David; Berg, Christoph; Willruth, Arne; Reutter, Heiko; Bartmann, Peter; Müller, Andreas; Zur, Berndt

    2017-01-01

    Background The aim of the present study is to evaluate the utility of extraction versus non-extraction-based commercial melatonin ELISA kits for determining the melatonin concentration in amniotic fluid obtained in early and late pregnancy. Methods Pregnancy duration less than 28 weeks was defined as early and from 28 weeks until delivery as late gestation. Nine samples were obtained in early and 18 in late pregnancy. Two commercially available melatonin ELISA kits (melatonin ELISA RE54021, including methanol-based extraction and direct saliva melatonin ELISA RE 54041, not including an extraction step, both from IBL-International, Germany) were used to determine melatonin concentrations in amniotic fluid. Results The mean melatonin concentration in ELISAs assayed by the non-extraction was significantly lower than those assayed after extraction. Subgroup analysis showed that there was no significant difference between melatonin concentration measured by non-extraction versus extraction ELISA in early pregnancy (11.2 ± 7.4 vs. 12.2 ± 7.7, respectively, P = 0.463) but that the mean melatonin concentration in late pregnancy was significantly lower when assayed by non-extraction ELISA than when assayed by extraction ELISA (14.8 ± 9.3 vs. 145.1 ± 179.3, respectively; P pregnancy was rather poor (r 2  = 0.271, P = 0.022), as opposed to the good correlation found in early pregnancy (r 2  = 0.929, P melatonin assay without an extraction step, such as direct saliva ELISA, does not seem to be a valid method to determine the melatonin concentration of amniotic fluid, especially in late gestation.

  7. DESAJUSTE EDUCATIVO POR REGIONES EN COLOMBIA: ¿COMPETENCIA POR SALARIOS O POR PUESTOS DE TRABAJO?

    Directory of Open Access Journals (Sweden)

    Maribel Castillo Caicedo

    2007-06-01

    Full Text Available Este trabajo aporta una perspectiva del fenómeno de la sobreeducación, entendida como un desajuste por exceso, entre el nivel educativo alcanzado por el individuo y el exigido por el puesto de trabajo en el cual se desempeña; esto se debe a que existe una demanda laboral estrecha de puestos de trabajo para personas calificadas en Colombia. Se analizan las contribuciones empíricas existentes y el debate sobre las mismas; se examinan las teorías que permiten explicar la existencia de un desajuste educativo y se realiza una revisión de la literatura internacional y nacional sobre el tema. Adicionalmente, se plantean una serie de hipótesis para desarrollar un esquema que permita determinar el comportamiento del individuo en el fenómeno de la sobreeducación.

  8. Consanguinidad por isonimia en Salta

    Directory of Open Access Journals (Sweden)

    Albeza, María V.

    2007-01-01

    Full Text Available Se estimó el coeficiente de parentesco por isonimia para localidades de la Puna, Valle Calchaquí y Valle de Lerma, a fin de evaluar diferentes factores evolutivos que podrían estar afectando la composición genética de la población. A partir de los apellidos de las parejas consignadas en fuentes primarias de información, se estimó la isonimia conyugal o marital, el coeficiente total Ft y sus componentes Fr (inbreeding azaroso y Fn (inbreeding no azaroso. De las localidades estudiadas, en la Puna se ha detectado sólo una pareja isónima en una de ellas, en el Valle Calchaquí, tres y ninguna en el Valle de Lerma. Tanto en el Valle Calchaquí como en el de Lerma, se han estimado valores negativos de Ft, y en la Puna se registran los valores más elevados. En las localidades estudiadas no se cumple el supuesto de transmisión patrilineal de apellidos por lo que los valores de Fr y por ende de Ft podrían estar subestimados. Es por ello que sería necesario contar con información desde otras vertientes metodológicas para corroborar, complementar y manejar cuidadosamente el análisis de los datos y las conclusiones que se obtienen.

  9. Detection of HBsAg and Anti HBc on donors of a blood bank by IRMA and ELISA methods

    International Nuclear Information System (INIS)

    Freire Martinez, D.Y.

    1985-10-01

    Comparative evaluation of two methods, Immunoradiometric Assay (IRMA) and Enzyme Immunoassay (ELISA), for detecting HBsAg and Anti HBc was made for determining which is the most advantageous and reliable. The study was made on 300 donors of the Hospital San Juan de Dios Blood Bank. In comparison with the reference method (IRMA), ELISA shows 91.67% of sensitivity. The Anti HBc detection by IRMA is more reliable than the HBsAg detection by IRMA and ELISA for determining the carrier state

  10. Celulitis por citomegalovirus Cytomegalovirus cellulitis

    Directory of Open Access Journals (Sweden)

    A. Ruiz Lascano

    2002-12-01

    Full Text Available Las lesiones cutáneas por citomegalovirus (CMV son infrecuentes y a menudo una manifestación tardía de una enfermedad sistémica, que generalmente anuncia un curso fatal. Comunicamos un caso de celulitis por CMV: una mujer de 70 años con trasplante renal efectuado 1 mes antes de la consulta, terapia inmunosupresora con ciclosporina A y metilprednisona. La paciente ingresó por fiebre, dolor e impotencia funcional en pierna derecha. Comprobamos la existencia de una placa de 8 por 4 cm eritematoedematosa. La tratamos con antibióticos sin mejoría, por lo que realizamos un estudio histopatológico de piel que mostró cambios citopáticos compatibles con infección por CMV. Los cultivos bacteriológicos y micológicos fueron negativos. La inmunohistoquímica específica para CMV y el estudio de reacción en cadena de la polimerasa (PCR de la biopsia de piel fueron positivas, al igual que la antigenemia. El tratamiento con ganciclovir produjo la mejoría del cuadro clínico. En la literatura revisada no hemos encontrado la celulitis como manifestación de enfermedad cutánea por CMV.Cutaneous lesions in CMV infection are rare, often a late manifestation of systemic infection, and usually herald a fatal course. A 70 year-old woman received a kidney transplantation one month before consulting and immunosuppressive therapy that included cyclosporine A and methylprednisone. She complained of fever, local pain in her right leg, and an erythematous and swelling plaque. She was treated with intravenous antibiotics without improvement. A skin biopsy was performed and the tissue obtained was sent for bacterial and fungal cultures as well as for histological examination. Cultures were negative. The biopsy showed CMV cytopathic changes. Immunoperoxidase staining was positive for CMV and polymerase chain reaction (PCR testing revealed CMV DNA. She was treated with ganciclovir with resolution of the lesion. CMV cellulitis is a rare cutaneous manifestation

  11. DEVELOPMENT AND EVALUATION OF AN ENZYME-LINKED IMMUNOASSAY (ELISA) METHOD FOR THE MEASUREMENT OF 2,4-DICHLOROPHENOXYACETIC ACID IN HUMAN URINE

    Science.gov (United States)

    This paper describes the development of a 96-microwell high sample capacity ELISA method for measuring 2,4-D in urine; the analysis of 2,4-D in real-world urine samples by both ELISA and GC/MS methods; and compares the ELISA and GC/MS results in several key areas: accuracy, preci...

  12. Evaluation of an enzyme-linked immunosorbent assay (ELISA) for the serological diagnosis of sarcoptic mange in dogs.

    Science.gov (United States)

    Lower, K S; Medleau, L M; Hnilica, K; Bigler, B

    2001-12-01

    Canine scabies is a challenging disease to diagnose because sarcoptic mites are hard to find on skin scrapings. The purpose of this study was to evaluate a serologic enzyme-linked immunosorbent assay (ELISA) as an aid in the diagnosis of canine scabies. In addition, serum samples were obtained post treatment to determine the duration and persistence of circulating scabies antibodies after resolution of natural infection. Nineteen dogs diagnosed with sarcoptic mange and 38 control dogs were tested. Sixteen scabies-infested dogs showed positive pretreatment ELISA results (84.2% sensitivity). Thirty-four control dogs showed negative ELISA results (89.5% specificity). In the 11 scabies dogs from which multiple post treatment serum samples were obtained, detectable antibodies were not present 1 month after treatment in four cases, but were present for 1-4.5 months post treatment in seven dogs. Our results suggest that this scabies ELISA test is useful in the diagnosis of canine scabies.

  13. Evaluation of an Anti-rPA IgG ELISA for Measuring the Antibody Response in Mice

    National Research Council Canada - National Science Library

    Little, S

    2004-01-01

    A recombinant protective antigen (rPA)-based enzyme-linked immunosorbent assay (ELISA) was developed to measure the serological response of female A/J mice after inoculation with the new rPA-based anthrax vaccine...

  14. Demonstration of immunogenic keratan sulphate in commercial chondroitin 6-sulphate from shark cartilage. Implications for ELISA assays

    DEFF Research Database (Denmark)

    Møller, H J; Møller-Pedersen, T; Damsgaard, T E

    1995-01-01

    The prototype monoclonal keratan sulphate (KS) antibody 5D4 that is widely used for detection of KS in tissues and biological fluids reacts strongly with commercial low grade shark cartilage chondroitin 6-sulphate. Characterization of the immunogenic material by chondroitinase ABC digestion, ELISA...... cartilage chondroitin 6-sulphate is an easy accessible source of immunogenic KS that can be used as a reference standard and as coating antigen in KS-ELISAs. The concentration of immunogenic KS in synovial fluid measured with an ELISA based solely on reagents of shark cartilage chondroitin 6-sulphate...... correlated well (r = 0.90) with the concentrations obtained with a traditional KS-ELISA that uses purified aggrecan as standard and coating antigen, and KS in both serum and synovial fluid could be measured with sufficient linearity....

  15. Partially purified fraction antigen from adult Fasciola Gigantic a for the serodiagnosis of human fascioliasis using Dot-ELISA technique

    International Nuclear Information System (INIS)

    Dalimi, Abdolhossein; Hadighi, Ramtin; Madani, Rasool

    2004-01-01

    Human fascioliasis has been reported in many countries including Iran. Various techniques have been evaluated for diagnosis of human fascioliasis using different antigens. We evaluated fasciola gigantica partially purified fraction antigen (PPF) isolated from sheep's liver fluke for the diagnosis of human fascioliasis. 261 sera was collected from 104 patients living in an area endemic for human fascioliasis from 89 non-fascioliasis patients living in a non-endemic area and from 68 healthy individuals. Micro-ELISA ws used in the evaluation of the sensitivity and the specificity of dot-ELISA. With a 1:800 sera dilution as the cut-off titer, the sensitivity of Dot-ELISA test in diagnosis of human fascioliasis was 94.23% and the specificity was 99.36%.Dot-ELISA using PPF antigen is sensitive and specific method for diagnosis of human fascioliasisthat is also rapid and inexpensive. (author)

  16. Application of a coproantigen ELISA as an indicator of efficacy against multiple life stages of Fasciola hepatica infections in sheep.

    Science.gov (United States)

    George, S D; Vanhoff, K; Baker, K; Lake, L; Rolfe, P F; Seewald, W; Emery, D L

    2017-11-15

    At present diagnosis of true resistance and determination of drug efficacy in Fasciola hepatica infection rely solely on terminal experiments. The coproantigen ELISA (cELISA) has been reported previously as a sensitive and specific tool appropriate to detect treatment failure, and potentially drug resistance. Two studies were conducted to determine whether the cELISA was appropriate for on-farm efficacy and resistance testing in Australian Merino sheep. In Study 1 sheep were infected orally with 50 F. hepatica metacercariae on three occasions, twelve, six and two weeks prior to a single flukicide treatment with triclabendazole, closantel or albendazole. Sheep were sampled weekly for a further seven weeks prior to necropsy. Following effective treatment, no faecal antigen was detected from 1 week. When immature stages (≤6 weeks) survived treatment, coproantigen reappeared from 6 weeks post-treatment. Therefore, cELISA conducted 1-4 weeks after treatment will demonstrate obvious treatment failure against adult F. hepatica, but is not sufficiently sensitive to detect survival of immature fluke until these reach maturity. In study 2, fluke burdens of sheep necropsied 13 weeks post single infection were compared to fecal worm egg counts (FWEC) and cELISA at necropsy. Regression analysis demonstrated that cELISA correlated strongly with fluke burden, whilst FWEC correlated weakly with cELISA. The correlation between FWEC and fluke burden was also weak, although stronger than that of FWEC with cELISA. The cELISA is an appropriate tool for monitoring effectiveness of treatments against Fasciola hepatica if an adult infection is present, however when immature stages of the parasite are present it is not as reliable. Where immature parasites are present it is recommended that initial cELISA be followed with a secondary cELISA at least 6 weeks after treatment to ensure resistance to immature stages is detected. Further testing is justified for monitoring the effectiveness

  17. Heterologous antigen extract in ELISA for the detection of human IgE anti-Strongyloides stercoralis Extrato antigênico heterólogo em ELISA para a detecção de IgE humana anti-Strongyloides stercoralis

    Directory of Open Access Journals (Sweden)

    Julia Maria Costa-Cruz

    2003-10-01

    ífica a Strongyloides sp. e IgE total nos soros de pacientes com estrongiloidíase. Em conclusão, extrato heterólogo de S. ratti mostrou ser uma ferramenta útil para detecção de IgE gênero-específica por ELISA, desta forma contribuindo para melhor caracterização do perfil da resposta imune na estrongiloidíase humana.

  18. Detection of IgE in the sera of rodents: comparison of the applicability of ELISA and RIA

    Energy Technology Data Exchange (ETDEWEB)

    Reiner, G; Zahner, H [Institut fuer Parasitologie der Justus-Liebig-Universitaet Giessen, Germany, F.R.; Haque, A [Institut Pasteur, 59 - Lille (France). Centre d' Immunologie et de Biologie Parasitaire

    1984-04-13

    RIA and ELISA were compared for their ability to detect IgE in different rodent species. With a sheep anti-rat IgE antibody good correlation (P < 0.001) between the 2 assay methods for IgE was found in rats. RIA failed to detect the IgE of Mastomys natalensis while ELISA proved to be a suitable test. However, both tests failed to measure IgE in sera of Nile rats.

  19. Esporotricosis diagnosticada por el laboratorio

    Directory of Open Access Journals (Sweden)

    Nelly Ordóñez

    1989-06-01

    Full Text Available De 1976 a 1989 se han diagnosticado 40 casos de esporotricosis en el laboratorio de Micología del Instituto Nacional de Salud. La enfermedad se presentó en pacientes entre 4 y 52 años y tuvo predilección por el sexo masculino: 35 de 40 (87,5%; las formas clínicas más frecuentes fueron la cutánea fija, 18 de 40 (45%, y la linfocutánea, 17 de 40 (42,5%, con localización mayor en miembros superiores, 18 de 40 (45%. El diagnóstico se estableció por el aislamiento del Sporothrix schenckii en 35 de 38 pacientes (92%; los otros dos pacientes se diagnosticaron empleando otras técnicas: inmunofluorescencia directa, intradermorreacción y aglutinación en tubo.

  20. Comparison of the serological tests ICT and ELISA for the diagnosis of alveolar echinococcosis in France.

    Science.gov (United States)

    Knapp, Jenny; Sako, Yasuhito; Grenouillet, Frédéric; Bresson-Hadni, Solange; Richou, Carine; Gbaguidi-Haore, Houssein; Ito, Akira; Millon, Laurence

    2014-01-01

    Serological diagnosis of alveolar echinococcosis (AE) is a key element for efficient patient treatment management. A rapid immunochromatography test kit (ICT) using the recombinant Em18 antigen (rEm18) was recently developed. The aim of our study was to assess this test on a panel of sera from French patients with alveolar echinococcosis and control patients. In a blind test, a total of 112 serum samples were tested including samples of AE (n = 30), cystic echinococcosis [CE] (n = 15), and polycystic echinococcosis [PE] (n = 1). For the comparison, 66 sera from patients with hepatocarcinoma, fascioliasis, toxocariasis, Caroli's disease, or autoimmune chronic active hepatitis were used. The diagnostic test sets we used were the rEm18-ICT and two validated ELISAs with rEm18 and Em2-Em18 antigens, respectively. For the ICT, 27/30 sera from AE patients, 4/15 sera from CE patients and the PE patient serum were positive. One serum from the control panel (toxocariasis) was positive for the ICT. The rEm18-ICT sensitivity (90.0%) and specificity (92.7%) for detection of Em18-specific antibodies confirmed it as a relevant tool for AE diagnosis. The rEm18-ELISA had a sensitivity of 86.7% and specificity of 91.5%, and the Em2-Em18-ELISA had a sensitivity of 96.7% and specificity of 87.8%. However, when AE patient sera are recorded as weak in intensity with the ICT, we recommend a double reading and use of a reference sample if the ICT is used for patient follow-up. © J. Knapp et al., published by EDP Sciences, 2014.

  1. Comparison of the quantification of caffeine in human plasma by gas chromatography and ELISA

    Directory of Open Access Journals (Sweden)

    A.B. Carregaro

    2001-06-01

    Full Text Available In the present study we evaluated the precision of the ELISA method to quantify caffeine in human plasma and compared the results with those obtained by gas chromatography. A total of 58 samples were analyzed by gas chromatography using a nitrogen-phosphorus detector and routine techniques. For the ELISA test, the samples were diluted to obtain a concentration corresponding to 50% of the absorbance of the standard curve. To determine whether the proximity between the I50 of the standard curve and that of the sample would bring about a more precise result, the samples were divided into three blocks according to the criterion of difference, in modulus, of the I50 of the standard curve and of the I50 of the sample. The samples were classified into three groups. The first was composed of 20 samples with I50 up to 1.5 ng/ml, the second consisted of 21 samples with I50 ranging from 1.51 to 3 ng/ml, and the third of 17 samples with I50 ranging from 3.01 to 13 ng/ml. The determination coefficient (R² = 0.999 showed that the data obtained by gas chromatography represented a reliable basis. The results obtained by ELISA were also reliable, with an estimated Pearson correlation coefficient of 0.82 between the two methods. This coefficient for the different groups (0.88, 0.79 and 0.49 for groups 1, 2 and 3, respectively showed greater reliability for the test with dilutions closer to I50.

  2. Enzyme-linked immunosorbent assay (ELISA) for the anthropogenic marker isolithocholic acid in water.

    Science.gov (United States)

    Baldofski, Stefanie; Hoffmann, Holger; Lehmann, Andreas; Breitfeld, Stefan; Garbe, Leif-Alexander; Schneider, Rudolf J

    2016-11-01

    Bile acids are promising chemical markers to assess the pollution of water samples with fecal material. This study describes the optimization and validation of a direct competitive enzyme-linked immunosorbent assay for the bile acid isolithocholic acid (ILA). The quantification range of the optimized assay was between 0.09 and 15 μg/L. The assay was applied to environmental water samples. Most studies until now were focused on bile acid fractions in the particulate phase of water samples. In order to avoid tedious sample preparation, we undertook to evaluate the dynamics and significance of ILA levels in the aqueous phase. Very low concentrations in tap and surface water samples made a pre-concentration step necessary for this matrix as well as for wastewater treatment plant (WWTP) effluent. Mean recoveries for spiked water samples were between 97% and 109% for tap water and WWTP influent samples and between 102% and 136% for WWTP effluent samples. 90th percentiles of intra-plate and inter-plate coefficients of variation were below 10% for influents and below 20% for effluents and surface water. ILA concentrations were quantified in the range of 33-72 μg/L in influent, 21-49 ng/L in effluent and 18-48 ng/L in surface water samples. During wastewater treatment the ILA levels were reduced by more than 99%. ILA concentrations of influents determined by ELISA and LC-MS/MS were in good agreement. However, findings in LC-ELISA experiments suggest that the true ILA levels in concentrated samples are lower due to interfering effects of matrix compounds and/or cross-reactants. Yet, the ELISA will be a valuable tool for the performance check and comparison of WWTPs and the localization of fecal matter input into surface waters. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Establishment of an indirect ELISA for detection of the novel antifibrotic peptide M10.

    Directory of Open Access Journals (Sweden)

    Tanjina Akter

    Full Text Available M10 is a ten amino acid peptide generated from the intracellular cytoplasmic tail of the hepatocyte growth factor (HGF receptor c-Met following cleavage by caspase-3. Recently we reported that M10 interacts with Smad2 and demonstrates antifibrotic properties in vitro and in vivo and can be advanced into a novel antifibrotic remedy. The current study was undertaken to develop an immunoassay to measure M10 concentration in biological specimens.An Indirect Enzyme-Linked Immunosorbent Assay (ELISA for detection of M10 in biological fluids was developed using pharmaceutical grade synthetic M10 as a calibrator and commercially available anti-c-Met C12 antibody.M10 ELISA specifically detected in plasma M10, but not a scrambled peptide, following a single intraperitoneal administration of M10 (1mg/kg to mice. The detection limit was 9.6 ng/ml, and the measuring limit was between 15 ng/ml and 200 ng/ml. The recovery limits of M10 were between 80% and 120%; intra-assay coefficient of variation was between 5.3% and 6.3%; inter-assay coefficient of variation was between 5.0% and 8.0% over the buffer concentration tested in the range from 15 ng /ml to 250 ng /ml. The peak of M10 concentration following a single intraperitoneal injection (1mg/kg was achieved within 6 hours and declined to minimal levels by 48 hours. The experimentally obtained half-life for M10 was comparable to the theoretically predicted half-life for M10.We have established a highly sensitive ELISA to detect the antifibrotic peptide M10 in plasma samples, which should prove to be a novel tool to study the pharmacokinetics and efficacy of M10 in the treatment of fibroproliferative disorders.

  4. A novel Python program for implementation of quality control in the ELISA.

    Science.gov (United States)

    Wetzel, Hanna N; Cohen, Cinder; Norman, Andrew B; Webster, Rose P

    2017-09-01

    The use of semi-quantitative assays such as the enzyme-linked immunosorbent assay (ELISA) requires stringent quality control of the data. However, such quality control is often lacking in academic settings due to unavailability of software and knowledge. Therefore, our aim was to develop methods to easily implement Levey-Jennings quality control methods. For this purpose, we created a program written in Python (a programming language with an open-source license) and tested it using a training set of ELISA standard curves quantifying the Fab fragment of an anti-cocaine monoclonal antibody in mouse blood. A colorimetric ELISA was developed using a goat anti-human anti-Fab capture method. Mouse blood samples spiked with the Fab fragment were tested against a standard curve of known concentrations of Fab fragment in buffer over a period of 133days stored at 4°C to assess stability of the Fab fragment and to generate a test dataset to assess the program. All standard curves were analyzed using our program to batch process the data and to generate Levey-Jennings control charts and statistics regarding the datasets. The program was able to identify values outside of two standard deviations, and this identification of outliers was consistent with the results of a two-way ANOVA. This program is freely available, which will help laboratories implement quality control methods, thus improving reproducibility within and between labs. We report here successful testing of the program with our training set and development of a method for quantification of the Fab fragment in mouse blood. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Miasis cutanea por cordylobia anthropophaga

    Directory of Open Access Journals (Sweden)

    Alkorta Gurrutxaga Miriam

    2001-01-01

    Full Text Available El incremento progresivo en el número de personas que viajan a países tropicales ha hecho que las enfermedades importadas adquieran una relevancia cada vez mayor. Las miasis (o infestaciones por larvas de moscas cutáneas se encuentran entre este tipo de enfermedades siendo especialmente frecuentes en países tropicales. A propósito de la observación de un caso de miasis cutánea masiva por Cordylobia antropophaga, que ocurrió en una mujer de 34 años de edad al volver de un viaje a Senegal, se ha efectuado una revisión de los casos de miasis cutáneas forunculoides importadas publicados en España, así como de la biología, patología, tratamiento y prevención de la miasis humana por Cordylobia anthropophaga. El caso referido, se caracterizó por la infestación con un número inusualmente elevado de larvas, no sospechándose su etiología hasta la fase final de la enfermedad. La emergencia continuada de larvas (se recogieron 91 generó en la paciente un estado de ansiedad importante. Finalmente, la eliminación de las larvas provocó una rápida mejoría de la paciente. Aunque los casos de miasis cutánea no tienen la gravedad de otras enfermedades importadas, su conocimiento es necesario desde el punto de vista preventivo, diagnóstico y terapeútico. Es importante proceder a la identificación morfológica de las larvas diferenciándolas de otro tipo de miasis con implicaciones terapéuticas diferentes.

  6. The diagnosis of bovine basesiosis (babesia bovis) by means of the test of ELISA

    International Nuclear Information System (INIS)

    Leon Arenas, Edgar; Guillen, Ana Teresa; Silva, Maglene

    1997-01-01

    Between 1994 and 1996 a kit ELISA, developed by the FAO - IAEA for the diagnose of bovine babesiosis produced by Babesia bovis, was validated. There were processed a total of 547 blood serums from bovine between 9 and 18 months old, coming from high and low risk to illness areas. The point obtained for the test was 0.178 (DO) and the resulting percentages inside the population studied was 48% animal positive and 52% bovine negative. These results confirm that bovine population in Venezuela is in enzootic uncertainty areas for bovine babesiosis [es

  7. Study of FAO/IAEA/PANAFTOSA ELISA kit for the detection of antibodies against FMD

    International Nuclear Information System (INIS)

    Ravison, J.A.; Andrade Goncalves, D. de; Souza, R. de

    1998-01-01

    Two groups of sera were used to evaluate a liquid phase blocking ELISA (LPBE) for the detection of antibody against foot-and-mouth disease virus. One hundred and twenty sera, from animals with no previous history of FMD infection or vaccination, were analyzed by screening assay at a final dilution of 1:32. A second group of 120 sera, from animals vaccinated with an oil trivalent vaccine (O, A, C) were tested by titration in the LPBE. All the sera were tested against virus of three FMD serotypes, using O 1 Campos, A 24 Cruzeiro, C 3 Indaial virus strains. (author)

  8. Influence of gamma radiation on antibodies fixation on polystyrene. Application to ELISA enzyme immunoassay

    International Nuclear Information System (INIS)

    Esterlin, S.

    1986-01-01

    This thesis is divided into two parts: the first part includes a description of the ELISA test, a comparative analysis of the main supports (polystyrene microtitration trays) used for this technique and an evaluation of gamma radiation effects on the quality of the supports. The study was carried out with the following antigens: Spiroplasma citri R8A2, a tymovirus and Tristeza virus. The second part dealt with the effects of gamma radiations on antibodies and antibody-support system (interaction immobilized immunoglobulins-plastic support) [fr

  9. Comparison of complement fixation and ELISA for diagnosis of foot-and-mouth disease

    International Nuclear Information System (INIS)

    Caballero, P.H.; Gonzalez, S.; Orue, P.M.; Vergara, N.N.

    1998-01-01

    Foot-and-mouth disease (FMD) virus is characterised by its rapid transmission and its great antigenic variability which require a requires a rapid and accurate diagnosis in the laboratory, in order to initiate an immediate response for control. From these studies it is clear that Enzyme linked immunosorbent assay (ELISA) has the advantage over the Complement fixation test (CFT) of being a test of high sensitivity and specificity. Therefore, this technique is now used in our laboratory for diagnosis to detect FMD virus (O-A-C) in epithelia from animals affected by the disease. (author)

  10. Assessment of an ELISA for serodiagnosis of active pulmonary tuberculosis in a Cuban population

    Directory of Open Access Journals (Sweden)

    Julio Cesar Ayala

    2015-10-01

    Full Text Available Objective: To explore the serodiagnostic potential of the five recombinant Mycobacterium tuberculosis antigens CFP-10 (Rv3874, ESAT-6 (Rv3875, APA (Rv1860, PstS-1 (Rv0934, Ag85A (Rv3804c and their combination in a Cuban population with active pulmonary tuberculosis. Methods: The serodiagnostic potential of the recombinant antigens rESAT-6, rCFP-10, rAPA, rPstS-1 produced in Escherichia coli, rAg85A produced in Streptomyces lividans and the combination of the five proteins was evaluated by an indirect ELISA. Humoral immune response was analysed in a group of 140 patients with active pulmonary tuberculosis (smear-, Mantoux- and culture-positive and in a control group consisting of 34 bacillus CalmetteGuerin vaccinated, Mantoux-negative, healthy subjects. Results: With the exception of CFP-10, the use of the separate recombinant antigens or the antigenic cocktail in ELISA-based serodiagnosis resulted in a significant difference in the mean optical densitiy values between sera of patients and healthy subjects. The highest sensitivity of the assay using single antigens, being 58.57%, was achieved with rPstS-1 compared to 27.14% with rCFP-10, 31.65% with Ag85A, 42.86% with rAPA and 44.29% with rESAT-6. Single antigen ELISAs provided high specificity values ranging from 94.12% to 97.06%. A cocktail of the aforementioned antigens increased the sensitivity to 87.14% and the specificity to 97.06%. Conclusions: An ELISA using a multi-antigen mix containing recombinant immuno-dominant antigens of Mycobacterium tuberculosis, namely, rCFP-10, rESAT-6, rAPA, rPstS-1 and rAg85, increases the sensitivity and specificity compared with that using the single antigens and shows potential as a complementary tool for the diagnosis of active pulmonary tuberculosis in Cuba.

  11. Sandwich ELISA for quantitative detection of human collagen prolyl 4-hydroxylase

    Directory of Open Access Journals (Sweden)

    Myllyharju Johanna

    2010-06-01

    Full Text Available Abstract Background We describe a method for specific, quantitative and quick detection of human collagen prolyl 4-hydroxylase (C-P4H, the key enzyme for collagen prolyl-4 hydroxylation, in crude samples based on a sandwich ELISA principle. The method is relevant to active C-P4H level monitoring during recombinant C-P4H and collagen production in different expression systems. The assay proves to be specific for the active C-P4H α2β2 tetramer due to the use of antibodies against its both subunits. Thus in keeping with the method C-P4H is captured by coupled to an anti-α subunit antibody magnetic beads and an anti-β subunit antibody binds to the PDI/β subunit of the protein. Then the following holoenzyme detection is accomplished by a goat anti-rabbit IgG labeled with alkaline phosphatase which AP catalyzes the reaction of a substrate transformation with fluorescent signal generation. Results We applied an experimental design approach for the optimization of the antibody concentrations used in the sandwich ELISA. The assay sensitivity was 0.1 ng of C-P4H. The method was utilized for the analysis of C-P4H accumulation in crude cell extracts of E. coli overexpressing C-P4H. The sandwich ELISA signals obtained demonstrated a very good correlation with the detected protein activity levels measured with the standard radioactive assay. The developed assay was applied to optimize C-P4H production in E. coli Origami in a system where the C-P4H subunits expression acted under control by different promoters. The experiments performed in a shake flask fed-batch system (EnBase® verified earlier observations that cell density and oxygen supply are critical factors for the use of the inducer anhydrotetracycline and thus for the soluble C-P4H yield. Conclusions Here we show an example of sandwich ELISA usage for quantifying multimeric proteins. The method was developed for monitoring the amount of recombinant C-P4H tetramer in crude E. coli extracts. Due

  12. Phospho-SMC1 in-Cell ELISA based Detection of Ataxia Telangiectasia

    Directory of Open Access Journals (Sweden)

    Majid Zaki dizaji

    2016-12-01

    Full Text Available BackgroundAtaxia telangiectasia (A-T is a common genetically inherited cause of early childhood-onset ataxia. The infrequency of this disease, vast phenotype variation, disorders with features similar to those of A-T, and lack of definite laboratory test, make diagnosis difficult.  In addition, there is no rapid reliable laboratory method for identifying A-T heterozygotes, who susceptible to ionizing radiation (IR, atherosclerosis, diabetes, and cancers. We used SMC1pSer966 (pSMC1 in-cell colorimetric ELISA to diagnosis and screen in A-T families.Materials and Methods: With informed consent, 2cc peripheral blood was collected from the 15 A-T patients, their parents, and 24 healthy controls with no family history of malignancy, diabetes, and atherosclerosis. Extracted peripheral blood mononuclear cells (PBMCs were cultured in poly-L-Lysine treated 96-well plate with density of 70,000 cells per well. SMC1 phosphorylation was evaluated with cell-based ELISA kit 1 hour after 5 Gy IR and the pSMC1data normalized with Glyceraldehyde-3-phosphate dehydrogenase (GAPDH.Results: SMC1 phosphorylation was significantly low in A-T`s PBMC (mean + standard deviation [SD]: 0.075 + 0.034 in comparison to carriers (mean + SD: 0.190 + 0.060 and healthy controls (mean + SD: 0.312 +0.081, but unluckily could only discriminate A-T patients (Area Under the Curve -receiver operating characteristic [AUC-ROC]: 1.00, 1.00-1.00. This method in spite of rapidness and simplicity showed poor imprecision (22.49% coefficient of variation [CV] for intraday imprecision.Conclusion: It seems pSMC1 assessment by in-cell ELISA can be used for detection of A-T patients, but it may not sensitive enough for identification of carriers. This ELISA test is very simple, rapid, and requires less than 2cc blood. Thus it may be proposed for the early differential diagnosis of A-T as an alternative method.

  13. Validation of an indirect ELISA for the detection of Trypanosoma congolense antibodies in Ethiopian cattle

    International Nuclear Information System (INIS)

    Tadesse, Y.; Kefyalew, H.; Kembata, G.; Nega, A.

    2000-01-01

    Control and eradication of African Animal Trypanosomosis can be achieved if the reliability of the methods to diagnose the disease could be improved. The techniques currently used in the diagnosis of trypanosomosis in Ethiopia are not sufficiently sensitive to detect all infected animals. In order to improve disease diagnosis the indirect antibody detection ELISA, developed by FAO/IAEA, was evaluated under field conditions. Accordingly, reference serum samples were collected from trypanosomosis free and endemic areas. Serum samples negative for trypanosomes were collected from the Central highlands of Ethiopia where there is no previous record of trypanosomosis. The samples were used to establish the threshold and the specificity of the test. Trypanosoma congolense positive sera (based on thin and thick smears and BCT) were collected from endemic areas in the Southwestern part of the country to estimate the sensitivity of the test. Out of 701 negative serum samples, 690 were identified as negative with the indirect antibody ELISA, whereas the remaining 11 were detected as positive. Moreover, of the 282 infected samples the ELISA detected 155 sera as positive, but the remaining 127 cases fell in the negative range. The positive/negative threshold established from negative reference sera was found to be 81.38%. Based on this threshold the specificity of the test was 98.43%, whilst the sensitivity was calculated as 54.96%. Thus, the complementary use of both the ELISA and parasitological methods is encouraged. Since the internal quality controls (IQC) did not fall in the ranges prescribed in the protocol provided by FAO/IAEA precision was achieved by comparing the plate to plate variation of the IQC based on the means plot. Accordingly the assay process indicated that there was no significant difference between individual mean of each plate regarding the strong positive (C++) and moderate positive (C+) controls. Nevertheless, considerable discrepancies were

  14. From LPF to eLISA: new approach in payload software

    Science.gov (United States)

    Gesa, Ll.; Martin, V.; Conchillo, A.; Ortega, J. A.; Mateos, I.; Torrents, A.; Lopez-Zaragoza, J. P.; Rivas, F.; Lloro, I.; Nofrarias, M.; Sopuerta, CF.

    2017-05-01

    eLISA will be the first observatory in space to explore the Gravitational Universe. It will gather revolutionary information about the dark universe. This implies a robust and reliable embedded control software and hardware working together. With the lessons learnt with the LISA Pathfinder payload software as baseline, we will introduce in this short article the key concepts and new approaches that our group is working on in terms of software: multiprocessor, self-modifying-code strategies, 100% hardware and software monitoring, embedded scripting, Time and Space Partition among others.

  15. Detection and determination of Melamine in infant formula by ELISA method

    Directory of Open Access Journals (Sweden)

    A Shakerian

    2012-05-01

    Full Text Available Thirty-six samples of infant formula with different production dates and various brands were purchased from Isfahan city during 2012. The samples were assayed for the presence and quantity of melamine by ELISA screening method. According to the results, in any infant formula melamine contamination was observed above the detection limit of the kit (10 µg/L. Therefore, it was concluded that the infant formula at Isfahan retail is not considered a health hazard from the melamine contamination point of view.

  16. Extending the ELisA Logbook to use MySQL

    CERN Document Server

    Osman Jama Ali, Yosuf

    2017-01-01

    ELisA (Electronic Logbook for the Information Storage of ATLAS Experiments at LHC) is a web tool that is used within the ATLAS community to keep track of the daily experiments and deployments within ATLAS. It is implemented using the Spring framework and consists of a web interface, a REST API and a set of client libraries. This Report summarises the process taken in replacing the Oracle database that is used with MySQL, as well as the incorporation of Docker as a deployment strategy in order to make the logbook more portable.

  17. ELISA-based assay for IP-10 detection from filter paper samples

    DEFF Research Database (Denmark)

    Drabe, Camilla Heldbjerg; Blauenfeldt, Thomas; Ruhwald, Morten

    2014-01-01

    IP-10 is a small pro-inflammatory chemokine secreted primarily from monocytes and fibroblasts. Alterations in IP-10 levels have been associated with inflammatory conditions including viral and bacterial infections, immune dysfunction, and tumor development. IP-10 is increasingly recognized as a b...... as a biomarker that predicts severity of various diseases and can be used in the immunodiagnostics of Mycobacterium tuberculosis and cytomegalovirus infection. Here, we describe an ELISA-based method to detect IP-10 from dried blood and plasma spot samples....

  18. Establishment of a quantitative ELISA capable of determining peptide - MHC class I interaction

    DEFF Research Database (Denmark)

    Sylvester-Hvid, C; Kristensen, N; Blicher, T

    2002-01-01

    dependent manner. Here, we exploit the availability of these molecules to generate a quantitative ELISA-based assay capable of measuring the affinity of the interaction between peptide and MHC-I. This assay is simple and sensitive, and one can easily envisage that the necessary reagents, standards......Many different assays for measuring peptide-MHC interactions have been suggested over the years. Yet, there is no generally accepted standard method available. We have recently generated preoxidized recombinant MHC class I molecules (MHC-I) which can be purified to homogeneity under denaturing...

  19. New ELISA technique for analysis of p53 protein/DNA binding properties

    Czech Academy of Sciences Publication Activity Database

    Jagelská, Eva; Brázda, Václav; Pospíšilová, Š.; Vojtěšek, B.; Paleček, Emil

    2002-01-01

    Roč. 267, č. 2 (2002), s. 227-235 ISSN 0022-1759 R&D Projects: GA ČR GA301/00/D001; GA AV ČR IAB5004203; GA ČR GA301/00/P094; GA ČR GA301/02/0831; GA MZd NC6404; GA MZd NC5343; GA AV ČR IAA4004110 Institutional research plan: CEZ:AV0Z5004920 Keywords : ELISA * p53 * DNA-binding Subject RIV: BO - Biophysics Impact factor: 2.598, year: 2002

  20. Clinical implications of carcinoembryonic antigen distribution in serum exosomal fraction-Measurement by ELISA.

    Directory of Open Access Journals (Sweden)

    Shozo Yokoyama

    Full Text Available Serum exosomal proteins have great potential as indicators of disease status in cancer, inflammatory or metabolic diseases. The association of a fraction of various serum proteins such as carcinoembryonic antigen (CEA with circulating exosomes has been debated. The establishment of a method to measure the exosomal fraction of such proteins might help resolve this controversy. The use of enzyme-linked immunosorbent assays (ELISAs to measure serum exosomal molecules, for example CEA, is rare in research laboratories and totally absent in clinical biology. In this study, we optimized a method for assessment of serum exosomal molecules combining a treatment by volume-excluding polymers to isolate the exosomes, their subsequent solubilization in an assay buffer and ELISA.One hundred sixteen consecutive patients with colorectal cancer were enrolled for this study between June 2015 and June 2016 at Wakayama Medical University Hospital (WMUH. Whole blood samples were collected from patients during surgery. Exosomes were isolated using the ExoQuick reagent, solubilized in an assay buffer and subjected to CEA detection by ELISA. The procedure of serum exosome isolation and the formulation of the assay buffer used for the ELISA were optimized in order to improve the sensitivity and specificity of the assay.A five-fold increase in the concentration of the exosomes in the assay buffer (using initial serum volume as a reference and the addition of bovine serum albumin (BSA resulted in more accurate measurements of the serum exosomal CEA. The thawing temperature of frozen serum samples before exosome extraction was also optimized. A validation study that included one hundred sixteen patients with colorectal cancer demonstrated that serum exosomal CEA from samples thawed at 25°C exhibited a better AUC value, sensitivity, and specificity as well as a more correct classification than serum CEA.We optimized an easy and rapid detection method for assessment of

  1. Validation of an indirect ELISA for the diagnosis of Babesia bovis in El Salvador

    International Nuclear Information System (INIS)

    Molina, G.; Cardona, D.A.

    1998-01-01

    Validation and a preliminary serological study of Babesia bovis was made in El Salvador, using the indirect ELISA kit provided by the Joint FAO/IAEA Division of the International Atomic Energy Agency. Sera were collected from 545 cattle involving 10 regions of the country and various ages of cattle between 8 and 16 months. These were tested from May 1993 to February 1994. A 79.5% prevalence was found, but with a wide range from (5.8-100%), explained by different farm managing systems and different breeds. (author)

  2. Newly established ELISA for N-ERC/mesothelin improves diagnostic accuracy in patients with suspected pleural mesothelioma.

    Science.gov (United States)

    Sato, Tadashi; Suzuki, Yohei; Mori, Takanori; Maeda, Masahiro; Abe, Masaaki; Hino, Okio; Takahashi, Kazuhisa

    2014-10-01

    Pleural mesothelioma is an aggressive tumor, commonly caused by exposure to asbestos. The prognosis of mesothelioma remains disappointing despite multimodal treatment. We reported previously that N-ERC/mesothelin could be a useful biomarker for the early diagnosis of pleural mesothelioma and developed an enzyme-linked immunosorbent assay (ELISA) system for its detection. However, the reproducibility of our previous 7-16 ELISA system has been revealed to be unsatisfactory. To measure N-ERC/mesothelin more precisely, we developed a new 7-20 ELISA system. The subjects of this study were patients who were referred to our department with suspected pleural mesothelioma. The current study demonstrated that the newly established 7-20 ELISA system improved the sensitivity and specificity for diagnosing pleural mesothelioma compared with the previous system. Moreover, the 7-20 ELISA system showed better reproducibility and displayed the tendency of both higher sensitivity and higher specificity in plasma than in serum. Particularly for the epithelioid type, the area under the curve (AUC) and the diagnostic accuracy of N-ERC/mesothelin were excellent; the AUC was 0.91, the sensitivity was 0.95, and the specificity was 0.76 in plasma. In conclusion, assessment of N-ERC/mesothelin with our newly established 7-20 ELISA system is clinically useful for the precise diagnosis of pleural mesothelioma. © 2014 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  3. An ELISA using recombinant TmHSP70 for the diagnosis of Taenia multiceps infections in goats.

    Science.gov (United States)

    Wang, Yu; Nie, Huaming; Gu, Xiaobin; Wang, Tao; Huang, Xing; Chen, Lin; Lai, Weimin; Peng, Xuerong; Yang, Guangyou

    2015-09-15

    Infections with the tapeworm Taenia multiceps are problematic for ruminant farming worldwide. Here we develop a novel and rapid method for serodiagnosis of T. multiceps infections via an indirect ELISA (iELISA) that uses a heat shock protein, namely, TmHSP70. We extracted the total RNA of T. multiceps from the protoscoleces of cysts dissected from the brains of infected goats. Subsequently, we successfully amplified, cloned and expressed the TmHSP70 gene in Escherichia coli BL21 (DE3). Western blot analysis showed that the recombinant protein (∼34 kDa molecular weight) was recognized by the coenurosis positive serum. Given these initial, robust immunogenic properties for recombinant TmHSP protein, we assessed the ELISA-based serodiagnostic potential of this gene. The indirect ELISA was then optimized to 2.70 μg/well dilution for antigen and 1:80 dilution for serum,while the cut-off value is 0.446. We report that our novel TmHSP ELISA detected T. multiceps sera with a sensitivity of 1:10240 and a specificity of 83.3% (5/6). In a preliminary application, this assay correctly confirmed T. multiceps infection in 30 infected goats, consistent with the clinical examination. This study has revealed that our novel iELISA, which uses the rTmHSP protein, provides a rapid test for diagnosing coenurosis. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Detection of Bovine IgG Isotypes in a PPA-ELISA for Johne's Disease Diagnosis in Infected Herds.

    Science.gov (United States)

    Fernández, Bárbara; Gilardoni, Liliana Rosa; Jolly, Ana; Colavecchia, Silvia Beatriz; Paolicchi, Fernando Alberto; Mundo, Silvia Leonor

    2012-01-01

    Johne's Disease or Paratuberculosis is a chronic granulomatous enteritis disease affecting ruminants. Detection of subclinically infected animals is difficult, hampering the control of this disease. The aim of this work was to evaluate the performance of detection of IgG isotypes in a PPA-ELISA to improve the recognition of cattle naturally infected with Map in different stages. A total of 108 animals from Tuberculosis-free herds were grouped as follows: exposed (n = 30), subclinically infected (n = 26), clinically infected (n = 14), and healthy controls (n = 38). Receiver-operating characteristic (ROC) curves of isotypes/PPA-ELISAs were constructed and areas under the curves were compared to evaluate the performance of each test. Our study demonstrated that the conventional PPA-ELISA (detecting IgG) is the best to identify clinically infected animals with high sensitivity (92.9%) and specificity (100%). Meanwhile, IgG2/PPA-ELISA improved the number of subclinically infected cattle detected as compared with conventional IgG/PPA-ELISA (53.8 versus 23.1%). In addition, it had the maximum sensitivity (65.0%, taking into account all Map-infected cattle). In conclusion, the combination of IgG and IgG2/PPA-ELISAs may improve the identification of Map-infected cattle in different stages of disease. The usefulness of IgG2 detection in serological tests for Johne's Disease diagnosis should be further evaluated.

  5. A commercial ELISA detects high levels of human H5 antibody but cross-reacts with influenza A antibodies.

    Science.gov (United States)

    Stelzer-Braid, Sacha; Wong, Bruce; Robertson, Peter; Lynch, Garry W; Laurie, Karen; Shaw, Robert; Barr, Ian; Selleck, Paul W; Baleriola, Cristina; Escott, Ros; Katsoulotos, Gregory; Rawlinson, William D

    2008-10-01

    Commercial serological assays to determine influenza A H5N1 infection are available, although the accuracy and reproducibility of these are not reported in detail. This study aimed to assess the validity of a commercial ELISA H5 hemagglutinin (HA) antibody kit. A commercial ELISA for detection of antibodies towards influenza A H5 HA was evaluated using human sera from vaccinated individuals. The ELISA was used to screen 304 sera with elevated influenza A complement fixation titres collected between the period 1995-2007. The ELISA was found to be accurate for sera with high levels of anti-H5 antibodies, and would be useful in clinical settings where a rapid result is required. Thirteen of the stored sera were positive using the ELISA, but were confirmed as negative for H5N1 exposure using further serological tests. Absorption studies suggested that antibodies towards seasonal H3N2 and H1N1 influenza may cross-react with H5 antigen, giving false positive results with the ELISA.

  6. Abdome agudo por obstrução por ileobiliar

    Directory of Open Access Journals (Sweden)

    Márcia Cristina de Alencastro

    Full Text Available OBJETIVO: descrever a experiência na abordagem dos doentes com abdome agudo por obstrução por IB, desde o diagnóstico até o tratamento definitivo. MÉTODOS: estudo retrospectivo incluindo todos os casos de IB tratados em um período de 23 anos. De acordo com a abordagem cirúrgica realizada, os pacientes foram divididos em dois grupos (1 enterolitotomia com colecistectomia no segundo momento; e (2 enterolitotomia, colecistectomia e abordagem da fístula. RESULTADOS: Doze pacientes foram incluídos, sendo 11 mulheres (91,6%, com média de idade de 72,2 anos. Todos os pacientes apresentavam doenças associadas, principalmente hipertensão arterial sistêmica (75%. Dois pacientes não apresentavam sintomas significativos de obstrução intestinal. O diagnóstico de IB foi realizado em seis pacientes (50% antes da laparotomia. O grupo 1 foi constituído de oito pacientes e o grupo 2 de quatro, e a morbidade foi, respectivamente, 33,3% e 8,3%. A mortalidade foi 16,6% (um paciente de cada grupo. CONCLUSÃO: O manejo do IB deve ser individualizado. O tratamento da obstrução mediante remoção do cálculo biliar por enterotomia proximal é a escolha inicial para o tratamento do IB. A colecistectomia e a correção da fístula bilioentérica podem ser realizadas juntamente com a remoção do cálculo, no entanto, em pacientes com comorbidades significativas, esses procedimentos devem ser realizados posteriormente.

  7. Use of monoclonal antibodies against Hendra and Nipah viruses in an antigen capture ELISA

    Directory of Open Access Journals (Sweden)

    Spiropoulou Christina F

    2010-06-01

    Full Text Available Abstract Background Outbreaks of Hendra (HeV and Nipah (NiV viruses have been reported starting in 1994 and 1998, respectively. Both viruses are capable of causing fatal disease in humans and effecting great economical loss in the livestock industry. Results Through screening of hybridomas derived from mice immunized with γ-irradiated Nipah virus, we identified two secreted antibodies; one reactive with the nucleocapsid (N protein and the other, the phosphoprotein (P of henipaviruses. Epitope mapping and protein sequence alignments between NiV and HeV suggest the last 14 amino acids of the carboxyl terminus of the N protein is the target of the anti-N antibody. The anti-P antibody recognizes an epitope in the amino-terminal half of P protein. These monoclonal antibodies were used to develop two antigen capture ELISAs, one for virus detection and the other for differentiation between NiV and HeV. The lower limit of detection of the capture assay with both monoclonal antibodies was 400 pfu. The anti-N antibody was used to successfully detect NiV in a lung tissue suspension from an infected pig. Conclusion The antigen capture ELISA developed is potentially affordable tool to provide rapid detection and differentiation between the henipaviruses.

  8. Production of recombinant flagellin to develop ELISA-based detection of Salmonella Enteritidis

    Directory of Open Access Journals (Sweden)

    Seyed Ali Mirhosseini

    Full Text Available ABSTRACT Food-borne diseases, caused by the pathogenic bacteria, are highly prevalent in the world. Salmonella is one of the most important bacterial genera responsible for this. Salmonella Enteritidis (SE is one of the non-typhoid Salmonellae that can be transmitted to human from poultry products, water, and contaminated food. In recent years, new and rapid detection methods such as enzyme-linked immunosorbent assay (ELISA and polymerase chain reaction (PCR have been developed. In this study, recombinant FliC (rFliC was produced to be used as an antigen. The immunization was conducted in mice with the purified recombinant FliC (rFliC. The mice were subcutaneously immunized with rFliC and elicited significant rFliC specific serum IgG antibodies. An indirect ELISA system was established for the detection of Salmonella Enteritidis. Our results confirmed that the recombinant flagellin can be one of the excellent indicators for the detection of Salmonella Enteritidis.

  9. Evaluation of an ELISA kit in the serological diagnosis of Babesia bovis for epidemiological studies

    International Nuclear Information System (INIS)

    Martins, J.R.; Correa, B.L.; Cereser, V.H.; Artiles, J.M.; Alves-Branco, F.P.J.

    1998-01-01

    An enzyme linked immunosorbent assay (ELISA) kit for detect antibodies to Babesia bovis, an intraerytrocitic bovine parasite was evaluated using known negative and positive samples and the results were compared with an indirect immunofluorescent antibody test (IFAT). Results obtained with field samples were used to estimate seroprevalence of B. bovis in an endemic area to the cattle tick (Boophilus microplus) vector of bovine babesiosis. Percentage of positivity (PP) values (optical density of tested serum/mean optical density of positive control) on 274 negative samples, had major values ranged in the frequency of 4.0 to 7.0 PP. Comparison between ELISA and IFAT showed an agreement of 93.3% on field sera samples, collected in areas of low, good and high soil fertility in the region of Bage (31 degree 20 min 13 sec S, 54 degree 06 min 21 sec W), RS, Brazil. From 5,082 tested sera, 3,751 (73%) were positive for B. bovis antibodies. No significant difference (P>0.05) was observed between results from calves living in areas of low and good soil fertility (80 and 82% of seroprevalence, respectively). However, calves living in soil of high fertility showed a minor inoculation rate for B. bovis (63% of seroprevalence), indicating needs of measures to prevent losses due to babesiosis. (author)

  10. [The lysate and recombinant antigens in ELISA-test-systems for diagnostic of herpes simplex].

    Science.gov (United States)

    Ganova, L A; Kovtoniuk, G V; Korshun, L N; Kiseleva, E K; Tereshchenko, M I; Vudmaska, M I; Moĭsa, L N; Shevchuk, V A; Spivak, N Ia

    2014-08-01

    The lysate and recombinant antigens of various production included informula of ELISA-test-systems were analyzed. The ELISA-test-systems are used for detection of IgG to Herpes simplex virus type I and II. For testing the panel of serums PTH 201 (BBI Inc.) were used. The samples of this panel contain antibodies to Herpes simplex virus type I and II in mixed titers. The 69 serums of donors were used too (17 samples had IgG to Herpes simplex virus type I, 23 samples to Herpes simplex virus type II and 29 samples had no antibodies to Herpes simplex virus). The diagnostic capacity of mixture of recombinant antigens gG1 Herpes simplex virus type I and gG2 Herpes simplex virus type II (The research-and-production complex "DiaprofMed") was comparable with mixture of lysate antigen Herpes simplex virus type I and II (Membrane) EIE Antigen ("Virion Ltd."). In the test-systems for differentiation of IgG to Herpes simplex virus type I the recombinant antigen gG1 Herpes simplex virus type I proved to be comparable with commercial analogue Herpes simplex virus-1 gG1M ("Viral Therapeutics Inc."'). At the same time, capacity to detect IgG to Herpes simplex virus type II in recombinant protein gG2 Herpes simplex virus type II is significantly higher than in its analogue Herpes simplex virus-2 gG2c ("Viral Therapeutics Inc.").

  11. Improved Soluble ScFv ELISA Screening Approach for Antibody Discovery Using Phage Display Technology.

    Science.gov (United States)

    Tohidkia, Mohammad R; Sepehri, Maryam; Khajeh, Shirin; Barar, Jaleh; Omidi, Yadollah

    2017-09-01

    Phage display technology (PDT) is a powerful tool for the isolation of recombinant antibody (Ab) fragments. Using PDT, target molecule-specific phage-Ab clones are enriched through the "biopanning" process. The individual specific binders are screened by the monoclonal scFv enzyme-linked immunosorbent assay (ELISA) that may associate with inevitable false-negative results. Thus, in this study, three strategies were investigated for optimization of the scFvs screening using Tomlinson I and J libraries, including (1) optimizing the expression of functional scFvs, (2) improving the sensitivity of ELISA, and (3) preparing different samples containing scFvs. The expression of all scFv Abs was significantly enhanced when scFv clones were cultivated in the terrific broth (TB) medium at the optimum temperature of 30 °C. The protein A-conjugated with horseradish peroxidase (HRP) was found to be a well-suited reagent for the detection of Ag-bound scFvs in comparison with either anti-c-myc Ab or the mixing procedure. Based on our findings, it seems there is no universal media supplement for an improved expression of all scFvs derived from both Tomlinson I and J libraries. We thus propose that expression of scFv fragments in a microplate scale is largely dependent on a variety of parameters, in particular the scFv clones and relevant sequences.

  12. Determination of aflatoxins in nuts of Tabriz confectionaries by ELISA and HPLC methods

    Directory of Open Access Journals (Sweden)

    Siahi Shadbad Mohammad Reza

    2012-06-01

    Full Text Available Purpose: Aflatoxins (AFs are a group of mycotoxins and secondary metabolites of various species of Aspergillus. There are various forms of aflatoxins including B1, B2, G1, G2, M1 and M2 types. Aflatoxins cause important health problems and have high potential effect on liver cancer. Therefore, numerous investigations have been conducted during last three decades. The aim of this work is to determine the contamination levels of nuts used by the confectionaries in Tabriz. Methods: A total of 142 samples including 35 almond , 26 walnut, 4 seeds of apricot, 6 sunflower seeds kernel, 6 sesame seed, 6 peanuts , 32 pistachio,13 hazelnuts and 14 cashews samples were collected from Tabriz confectionaries. The ELISA method was employed for the screening of total aflatoxins. Results: In 13 cases (28.1% of pistachios, 5.1% of walnuts and 7.1% of cashews contamination rate of higher than 15 ppb were observed. The HPLC method was applied for the confirmation of ELISA results. Aflatoxin B1 was the highest detected AFs. Conclusion: The overall results of the tested samples indicated that the rate of contamination of pistachios is higher than the other tested samples.

  13. Development of ELISA for the detection of transgenic vegetative insecticidal protein in GM crops/produce.

    Science.gov (United States)

    Kumar, R

    2012-01-11

    In the process of the development of insect-resistant genetically modified (GM) crops and also to evaluate the consistency in the expression of toxin under field conditions, immunological assays are commonly being used. An immunoassay was developed to support the labelling of vegetative insecticidal protein (Vip3A)-based GM produce. The developed ELISA for the measurement of Vip3A is a triple antibody sandwich procedure utilising a polyclonal capture antibody (mouse anti-Vip3A) and a polyclonal detection antibody (rabbit anti-Vip3A) followed by use of a third HRP-conjugated anti-species antibody (goat anti-rabbit IgG). The limit of detection limit of the ELISA assay was 16 ng ml(-1) with a linear quantification range from approximately 31 to 500 ng ml(-1) of Vip3A protein. Furthermore, the assay was in-house validated with GM brinjal samples. The assay was specific, sensitive and reproducible, which can be helpful to detect and track down the spread of unapproved and intentionally/unintentionally released GM produce harbouring Vip protein.

  14. Interpolation of the magnetic field at the test masses in eLISA

    International Nuclear Information System (INIS)

    Mateos, I; Díaz-Aguiló, M; Ramos-Castro, J; García-Berro, E; Lobo, A

    2015-01-01

    A feasible design for a magnetic diagnostics subsystem for eLISA will be based on that of its precursor mission, LISA Pathfinder. Previous experience indicates that magnetic field estimation at the positions of the test masses has certain complications. This is due to two reasons. The first is that magnetometers usually back-act due to their measurement principles (i.e., they also create their own magnetic fields), while the second is that the sensors selected for LISA Pathfinder have a large size, which conflicts with space resolution and with the possibility of having a sufficient number of them to properly map the magnetic field around the test masses. However, high-sensitivity and small-sized sensors that significantly mitigate the two aforementioned limitations exist, and have been proposed to overcome these problems. Thus, these sensors will be likely selected for the magnetic diagnostics subsystem of eLISA. Here we perform a quantitative analysis of the new magnetic subsystem, as it is currently conceived, and assess the feasibility of selecting these sensors in the final configuration of the magnetic diagnostic subsystem. (paper)

  15. Biomimetic ELISA detection of malachite green based on molecularly imprinted polymer film.

    Science.gov (United States)

    Li, Lu; Peng, Ai-Hong; Lin, Zheng-Zhong; Zhong, Hui-Ping; Chen, Xiao-Mei; Huang, Zhi-Yong

    2017-08-15

    A highly selective and sensitive enzyme-linked immunosorbent assay (ELISA) was developed for the detection of malachite green (MG) using a molecularly imprinted polymer (MIP) film as bionic antibody. The MIP film, based on the self-polymerization of dopamine, was fabricated on the surfaces of a 96-well microplate. It showed specific recognition for MG in aqueous solution. A direct competitive ELISA method was established with the sensitivity reaching 10.31μgL -1 and the detection limit being 0.3μgL -1 . The cross-reactivity of two structural analogues to MG was less than 10%. The average recovery tested by MG standard spiking was 88.8% for bass and 90.4% for water, and the relative standard deviations were less than 3.6%. All the above results indicated that the developed method could be used to detect MG in fish and water samples rapidly, specifically and accurately. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Identification of the antigenic region of Neospora caninum dense granule protein 7 using ELISA.

    Science.gov (United States)

    Abdelbaky, Hanan H; Fereig, Ragab M; Nishikawa, Yoshifumi

    2018-06-26

    Dense granule protein 7 (NcGRA7) is a potent diagnostic antigen of Neospora caninum. Some studies have reported on the difficult expression, low yield, and variable degree of solubility of recombinant NcGRA7. We aimed to unravel the possible causes for these issues and tested NcGRA7 antigenicity in enzyme linked immunosorbent assays (ELISAs). The NcGRA7 coding sequence (217 amino acids) was split into five amino acid regions: NcGRA7m (27-217), NcGRA7m3 (27-160), NcGRA7m4 (27-135), NcGRA7m5 (161-190), and NcGRA7m6 (188-217). Three fragments, NcGRA7m, NcGRA7m3 and NcGRA7m4, exhibited high antigenic properties when tested against experimentally-infected mice and dog sera by ELISA. High levels of IgG2 antibodies against NcGRA7m were observed in field dog sera. In experimentally and naturally-infected cattle, the N. caninum-specific sera only reacted with NcGRA7m, indicating that this antigenic region differs among the three animal species. This study presents valuable information about the antigenic properties and topology of NcGRA7, and highlights its suitability for diagnostic purposes. Copyright © 2018. Published by Elsevier B.V.

  17. Rapid ELISA Using a Film-Stack Reaction Field with Micropillar Arrays.

    Science.gov (United States)

    Suzuki, Yuma; Morioka, Kazuhiro; Ohata, Soichiro; Shimizu, Tetsuhide; Nakajima, Hizuru; Uchiyama, Katsumi; Yang, Ming

    2017-07-11

    A film-stack reaction field with a micropillar array using a motor stirrer was developed for the high sensitivity and rapid enzyme-linked immunosorbent assay (ELISA) reaction. The effects of the incubation time of a protein (30 s, 5 min, and 10 min) on the fluorescence intensity in ELISAs were investigated using a reaction field with different micropillar array dimensions (5-µm, 10-µm and 50-µm gaps between the micropillars). The difference in fluorescence intensity between the well with the reaction field of 50-µm gap for the incubation time of 30 s and the well without the reaction field with for incubation time of 10 min was 6%. The trend of the fluorescence intensity in the gap between the micro pillars in the film-stack reaction field was different between the short incubation time and the long incubation time. The theoretical analysis of the physical parameters related with the biomolecule transport indicated that the reaction efficiency defined in this study was the dominant factor determining the fluorescence intensity for the short incubation time, whereas the volumetric rate of the circulating flow through the space between films and the specific surface area were the dominant factors for the long incubation time.

  18. Amyloid-β oligomer detection by ELISA in cerebrospinal fluid and brain tissue.

    Science.gov (United States)

    Bruggink, Kim A; Jongbloed, Wesley; Biemans, Elisanne A L M; Veerhuis, Rob; Claassen, Jurgen A H R; Kuiperij, H Bea; Verbeek, Marcel M

    2013-02-15

    Amyloid-β (Aβ) deposits are important pathological hallmarks of Alzheimer's disease (AD). Aβ aggregates into fibrils; however, the intermediate oligomers are believed to be the most neurotoxic species and, therefore, are of great interest as potential biomarkers. Here, we have developed an enzyme-linked immunosorbent assay (ELISA) specific for Aβ oligomers by using the same capture and (labeled) detection antibody. The ELISA predominantly recognizes relatively small oligomers (10-25 kDa) and not monomers. In brain tissue of APP/PS1 transgenic mice, we found that Aβ oligomer levels increase with age. However, for measurements in human samples, pretreatment to remove human anti-mouse antibodies (HAMAs) was required. In HAMA-depleted human hippocampal extracts, the Aβ oligomer concentration was significantly increased in AD compared with nondemented controls. Aβ oligomer levels could also be quantified in pretreated cerebrospinal fluid (CSF) samples; however, no difference was detected between AD and control groups. Our data suggest that levels of small oligomers might not be suitable as biomarkers for AD. In addition, we demonstrate the importance of avoiding HAMA interference in assays to quantify Aβ oligomers in human body fluids. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Assessing protein oxidation by inorganic nanoparticles with enzyme-linked immunosorbent assay (ELISA).

    Science.gov (United States)

    Sun, Wenjie; Luna-Velasco, Antonia; Sierra-Alvarez, Reyes; Field, Jim A

    2013-03-01

    Growth in the nanotechnology industry is leading to increased production of engineered nanoparticles (NPs). This has given rise to concerns about the potential adverse and toxic effects to biological system and the environment. An important mechanism of NP toxicity is oxidative stress caused by the formation of reactive oxygen species (ROS) or via direct oxidation of biomolecules. In this study, a protein oxidation assay was developed as an indicator of biomolecule oxidation by NPs. The oxidation of the protein, bovine serum albumin (BSA) was evaluated with an enzyme-linked immunosorbent assay (ELISA) to measure the protein carbonyl derivatives formed from protein oxidation. The results showed that some NPs such as Cu(0), CuO, Mn(2)O(3), and Fe(0) caused oxidation of BSA; whereas, many of the other NPs tested were not reactive or very slowly reactive with BSA. The mechanisms involved in the oxidation of BSA protein by the reactive NPs could be attributed to the combined effects of ROS-dependent and direct protein oxidation mechanisms. The ELISA assay is a promising method for the assessment of protein oxidation by NPs, which can provide insights on NP toxicity mechanisms. Copyright © 2012 Wiley Periodicals, Inc.

  20. The Electronic Logbook for the Information Storage of ATLAS Experiment at LHC (ELisA)

    International Nuclear Information System (INIS)

    Corso Radu, A; Lehmann Miotto, G; Magnoni, L

    2012-01-01

    A large experiment like ATLAS at LHC (CERN), with over three thousand members and a shift crew of 15 people running the experiment 24/7, needs an easy and reliable tool to gather all the information concerning the experiment development, installation, deployment and exploitation over its lifetime. With the increasing number of users and the accumulation of stored information since the experiment start-up, the electronic logbook actually in use, ATLOG, started to show its limitations in terms of speed and usability. Its monolithic architecture makes the maintenance and implementation of new functionality a hard-to-almost-impossible process. A new tool ELisA has been developed to replace the existing ATLOG. It is based on modern web technologies: the Spring framework using a Model-View-Controller architecture was chosen, thus helping building flexible and easy to maintain applications. The new tool implements all features of the old electronic logbook with increased performance and better graphics: it uses the same database back-end for portability reasons. In addition, several new requirements have been accommodated which could not be implemented in ATLOG. This paper describes the architecture, implementation and performance of ELisA, with particular emphasis on the choices that allowed having a scalable and very fast system and on the aspects that could be re-used in different contexts to build a similar application.

  1. Prevalence of Toxoplasma gondii in Chicken samples from delta of Egypt using ELISA, histopathology and immunohistochemistry.

    Science.gov (United States)

    Ibrahim, Hany M; Abdel-Ghaffar, Fathy; Osman, Gamalat Y; El-Shourbagy, Safinaz H; Nishikawa, Yoshifumi; Khattab, Reham A

    2016-06-01

    Estimates of the zoonotic diseases are helpful for monitoring and improving public health. Laboratory-based surveillance provides crucial information for assessing zoonotic disease trends and developments. Toxoplasmosis is considered as a zoonotic disease and has both medical and veterinary importance since it leads to abortion in humans and several animal species. In view of the worldwide importance of T. gondii, this study aimed to estimate the prevalence of T. gondii in chickens from the Delta of Egypt. A total of 304 blood and brain samples were collected from Egyptian chickens from Gharbiya, Qalyoubiya, Minufiya, Beheira, Kafr EL-Shaykh and Dakahlia Provinces. In order to determine the serological and histopathological prevalence of T. gondii, the samples were examined by ELISA, histopathology and immunohistochemistry (IHC). The prevalence of T. gondii was 11.18, 6.91, 6.91 % by ELISA, histopathology and IHC, respectively. Statistically significant differences in the prevalence of T. gondii were observed on the basis of season, sex and habitat. These data provide valuable information regarding the epidemiology of T. gondii infections in Egyptian chickens, which can be employed in developing efficient strategies for disease management and control.

  2. A Monoclonal Antibody Based Capture ELISA for Botulinum Neurotoxin Serotype B: Toxin Detection in Food

    Directory of Open Access Journals (Sweden)

    Larry H. Stanker

    2013-11-01

    Full Text Available Botulism is a serious foodborne neuroparalytic disease, caused by botulinum neurotoxin (BoNT, produced by the anaerobic bacterium Clostridium botulinum. Seven toxin serotypes (A–H have been described. The majority of human cases of botulism are caused by serotypes A and B followed by E and F. We report here a group of serotype B specific monoclonal antibodies (mAbs capable of binding toxin under physiological conditions. Thus, they serve as capture antibodies for a sandwich (capture ELISA. The antibodies were generated using recombinant peptide fragments corresponding to the receptor-binding domain of the toxin heavy chain as immunogen. Their binding properties suggest that they bind a complex epitope with dissociation constants (KD’s for individual antibodies ranging from 10 to 48 × 10−11 M. Assay performance for all possible combinations of capture-detector antibody pairs was evaluated and the antibody pair resulting in the lowest level of detection (L.O.D., ~20 pg/mL was determined. Toxin was detected in spiked dairy samples with good recoveries at concentrations as low as 0.5 pg/mL and in ground beef samples at levels as low as 2 ng/g. Thus, the sandwich ELISA described here uses mAb for both the capture and detector antibodies (binding different epitopes on the toxin molecule and readily detects toxin in those food samples tested.

  3. A monoclonal antibody based capture ELISA for botulinum neurotoxin serotype B: toxin detection in food.

    Science.gov (United States)

    Stanker, Larry H; Scotcher, Miles C; Cheng, Luisa; Ching, Kathryn; McGarvey, Jeffery; Hodge, David; Hnasko, Robert

    2013-11-18

    Botulism is a serious foodborne neuroparalytic disease, caused by botulinum neurotoxin (BoNT), produced by the anaerobic bacterium Clostridium botulinum. Seven toxin serotypes (A-H) have been described. The majority of human cases of botulism are caused by serotypes A and B followed by E and F. We report here a group of serotype B specific monoclonal antibodies (mAbs) capable of binding toxin under physiological conditions. Thus, they serve as capture antibodies for a sandwich (capture) ELISA. The antibodies were generated using recombinant peptide fragments corresponding to the receptor-binding domain of the toxin heavy chain as immunogen. Their binding properties suggest that they bind a complex epitope with dissociation constants (KD's) for individual antibodies ranging from 10 to 48 × 10-11 M. Assay performance for all possible combinations of capture-detector antibody pairs was evaluated and the antibody pair resulting in the lowest level of detection (L.O.D.), ~20 pg/mL was determined. Toxin was detected in spiked dairy samples with good recoveries at concentrations as low as 0.5 pg/mL and in ground beef samples at levels as low as 2 ng/g. Thus, the sandwich ELISA described here uses mAb for both the capture and detector antibodies (binding different epitopes on the toxin molecule) and readily detects toxin in those food samples tested.

  4. Occurrence of infectious laryngotracheitis outbreaks in commercial layer hens detected by ELISA.

    Science.gov (United States)

    Aras, Zeki; Yavuz, Orhan; Sanioğlu Gölen, Gökçenur

    2018-02-09

    Infectious laryngotracheitis (ILT) is an acute respiratory disease of chickens and a cause of great economic loss in commercial layers. The aims of this study were to investigate the prevalence of ILT in the field outbreaks and to compare the characteristics of ILT-infected and free flocks of commercial layers. A total of 625 blood serum samples were collected from 25 different layer flocks. The presence of antibodies against infectious laryngotracheitis virus (ILTV) in each sample was determined by ELISA. Of the 625 serum samples, 266 (42.56%) were found to be positive for ILTV antibodies. A total of 16 (64%) flocks were detected ILT positive by ELISA method. The mortality of infected flocks was statistically higher (P  0.05) than hens in free flocks. In conclusion, the results of this study indicated a high prevalence of ILT infection in the commercial layer flocks in Konya region, Turkey. In outbreaks, ILT significantly increased the mortality rate and decreased the average live weight in layer hens.

  5. Desajuste educativo por regiones en Colombia: ¿competencia por salarios o por puestos de trabajo?

    Directory of Open Access Journals (Sweden)

    Castillo Caicedo Maribel

    2007-08-01

    Full Text Available Este trabajo aporta una perspectiva del fenómeno de la sobreeducación,
    entendida como un desajuste por exceso, entre el nivel educativo alcanzado
    por el individuo y el exigido por el puesto de trabajo en el cual se
    desempeña; esto se debe a que existe una demanda laboral estrecha de
    puestos de trabajo para personas calificadas en Colombia. Se analizan las
    contribuciones empíricas existentes y el debate sobre las mismas; se
    examinan las teorías que permiten explicar la existencia de un desajuste
    educativo y se realiza una revisión de la literatura internacional y
    nacional sobre el tema. Adicionalmente, se plantean una serie de hipótesis
    para desarrollar un esquema que permita determinar el comportamiento
    del individuo en el fenómeno de la sobreeducación.

  6. Muerte materna por malaria grave por Plasmodium vivax

    Directory of Open Access Journals (Sweden)

    Nancy Arróspide

    Full Text Available Se presenta el caso de una mujer de 19 años con 29 semanas de gestación, procedente de Llumpe (Ancash con antecedentes de viajes a las localidades de Chanchamayo (Junín y Rinconada (Ancash. Ingresó al Hospital de Chacas (Ancash por presentar mal estado general, deshidratación, dificultad respiratoria, ictericia, sensación de alza térmica y dolor abdominal, tuvo reporte de: hemoparásitos 60% en frotis sanguíneo. Fue transferida al Hospital Ramos Guardia (Huaraz donde presentó mayor dificultad respiratoria, coluria, hematuria, disminución del débito urinario y reporte de Plasmodium (+, luego fue transferida al Hospital Cayetano Heredia (Lima donde ingresó a la Unidad de Cuidados Intensivos (UCI, con evolución a falla multiorgánica, óbito fetal y muerte materna. Se confirmó infección por Plasmodium vivax. Destacamos la importancia de mejorar nuestras capacidades de diagnóstico y manejo para brindar un tratamiento adecuado y oportuno.

  7. Miasis ocular por Oestrus ovis

    Directory of Open Access Journals (Sweden)

    María Beltrán F

    2006-01-01

    Full Text Available Se presentan tres casos de miasis ocular (dos adultos y un niñoprocedentes de zonas ganaderas de la provincia de Huaura,departamento de Lima,que acudieron al Hospital Regional de Huacho por presentar el ojo rojo,fotofobia, edema palpebral y sensación de cuerpo extraño;se extrajeron larvas adheridas al canto interno del ojo,las cuales se recibieron en el Instituto Nacional de Salud y fueron identificadas como Oestrus ovis .

  8. Comparison between microscopic examination, ELISA and quantitative buffy coat analysis in the diagnosis of falciparum malaria in an endemic population.

    Science.gov (United States)

    Tanpradist, S; Tharavanij, S; Yamokgul, P; Bualombai, P; Wongchotigul, V; Singhasivanon, P; Patarapotikul, J; Thammapalerd, N; Prasittisuk, C; Tantanasrikul, S

    1995-03-01

    Monoclonal antibody-based ELISA and QBC (quantitative buffy coat analysis) were tested in two endemic areas with low and high incidence of malaria in Kanchanaburi Province, West Thailand with annual parasite incidence in 1992 of 119 and 5 per 1,000 population, respectively. The numbers of individuals positive by thick blood film examination (TBF) for P. falciparum with or without P. vivax, and P. vivax only were 82 and 69, respectively. The detection limit of ELISA was 10 parasites/10(6) red blood cells (RBC) (0.001% parasitemia). Of 1,095 individuals involved in the study at the beginning of the study, ELISA showed sensitivity, specificity, positive predictive value and negative predictive value of 78.1%, 94.9%, 72% and 98.1%, respectively. Nine of 18 (50%) TBF-positive but ELISA-positive individuals had parasitemia of less than 10 parasites/10(6) RBC. High and low incidence areas did not affect the validity of our result. Regression analysis showed good correlation between log parasitemia and ELISA percent OD increase (Y = 0 + 64.9*logX, r = 0.65), and agreement between TBF and ELISA results was 95.9%. In a fortnightly follow-up, in 82 TBF-positive individuals, both ELISA and TBF positive rates correlatively declined with agreement of 96.3%. With samples taken on the first day of the study, the TBF and QBC results were also correlated with agreement of 95.8% for P. falciparum, 95.6% for P. vivax. During 8 week follow-up involving altogether 191 samples, agreement between TBF and QBC results were 87.4% for P. falciparum. QBC detected more cases with P. falciparum infections but detected smaller number of cases with P. vivax infections.

  9. Comparative diagnostic efficacy of recombinant LLO and PI-PLC-based ELISAs for detection of listeriosis in animals.

    Science.gov (United States)

    Suryawanshi, Rahul D; Malik, Satya Veer Singh; Jayarao, Bhushan; Chaudhari, Sandeep P; Savage, Emily; Vergis, Jess; Kurkure, Nitin V; Barbuddhe, Sukhadeo B; Rawool, Deepak B

    2017-06-01

    The present study for the first time evaluates the serodiagnostic efficacy of two recombinant antigens namely, listeriolysin O (rLLO) and phosphatidyl-inositol phospholipase C (rPI-PLC). Indirect ELISA with the above recombinant antigens was used on samples collected from bovines (n=106), goats (n=138) and pigs (n=92) having either a history of abortion, emaciation and/or apparently healthy animals. Isolation of Listeria was attempted from the blood samples using USDA-FSIS method. On screening of test sera by rLLO-based ELISA, antibodies against anti-listeriolysin O (ALLO) were observed in goats (22.46%), bovines (15.10%) and pigs (16.31%). As advocated, after adsorption of positive serum samples with streptolysin O (SLO), the seropositivity for ALLO was marginally reduced (p>0.05) in goats (21.73%) and bovines (10.38%), whereas, in pigs the reduction (5.43%) was significant (pPLC-based ELISA revealed higher non-specific seropositivity for antilisterial antibodies in goats (45.65%), bovines (31.13%) and pigs (8.69%). Further, on comparing the seropositivity with isolation rate, of the 16 animals that were culturally-positive for L. monocytogenes, 15 showed ALLO positivity in unadsorbed as well as SLO-adsorbed sera by rLLO-based ELISA, however, rPI-PLC-based ELISA could detect seropositivity in only 5 animals. Moreover, rPI-PLC-based ELISA also showed seropositivity in those animals (7/30) that were culturally positive for other Listeria spp. In conclusion, rLLO can serve as a better antigen than rPI-PLC in ELISA for the serodiagnosis of listeriosis in animals; however, prior adsorption of test sera with SLO is required to avoid false positive results. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. ELISA Cut-off Point for the Diagnosis of Human Brucellosis; a Comparison with Serum Agglutination Test

    Directory of Open Access Journals (Sweden)

    Anahita Sanaei Dashti

    2012-03-01

    Full Text Available Background: Brucellosis is a world-wide disease, which has a diverse clinical manifestation, and its diagnosis has to be proven by laboratory data. Serum agglutination test (SAT is the most-widely used test for diagnosing brucellosis. The enzyme linked immunosorbent assay (ELISA can also determine specific antibody classes against brucella. It is a sensitive, simple and rapid test, which could be an acceptable alternative to SAT with fewer limitations, however, like any other new test it should be further evaluated and standardized for various populations. This study was planned to determine an optimal cut-off point, for ELISA which would offer maximum sensitivity and specificity for the test when compared to SAT.Methods: Four hundred and seven patients with fever and other compatible symptoms of brucellosis were enrolled in the study. Serum agglutination test, 2-Mercaptoethanol test, and ELISA were performed on their sera. Results: The cut-off point of 53 IU/ml of ELISA-IgG yielded the maximal sensitivity and specificity comparing to the other levels of ELISA-IgG, and was considered the best cut off-point of ELISA-IgG to diagnose acute brucellosis. At this cut-off, the sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio were 84.09%, 85.38%, 62.20, 94.90, 5.75, 0.18, respectively.Conclusion: The best cut-off point of ELISA-IgG is 53 IU/ml, which yields the maximal sensitivity and specificity to diagnose acute brucellosis.

  11. Hipoglucemia inducida por carcinoma adrenal

    Directory of Open Access Journals (Sweden)

    Jimena Soutelo

    2013-08-01

    Full Text Available El carcinoma suprarrenal es una neoplasia maligna infrecuente y de mal pronóstico. La presentación clínica más común es originada por la producción hormonal excesiva, mientras que el desarrollo de hipoglucemia sintomática es excepcional. Presentamos el caso de una mujer de 37 años que ingresó al hospital por síntomas de hipoglucemias graves, hipertensión arterial, hipopotasemia y amenorrea secundaria. En el laboratorio se halló hipoglucemia con insulina inhibida y niveles de andrógenos en rango tumoral. La tomografía computarizada (TC de abdomen y pelvis mostró voluminosa formación heterogénea de aspecto sólido sin plano de clivaje con respecto al parénquima hepático e intenso realce con contraste. Luego de la extirpación de la masa retroperitoneal, evolucionó con valores de glucemia y potasemia normales, estabilizó la presión arterial y recuperó los ciclos menstruales.

  12. La curiosidad por la naturaleza

    Directory of Open Access Journals (Sweden)

    José Vicente Rodríguez

    2016-07-01

    Full Text Available Esta actitud es un instrumento estratégico para estimular procesos de desarrollo realmente sostenibles, donde se aproveche la admiración que nos embarga al conocer y apreciar lo que nos rodea para responsablemente utilizar y conservar nuestros recursos naturales. Con esta reflexión deseo resaltar esa motivación de escudriñar lo desconocido, que fue también la virtud que propició el desarrollo de la personalidad de Francisco José de Caldas y Tenorio, uno de nuestros primeros y connotados sabios colombianos, y en cuyo honor se constituyó la revista de divulgación científica más importante del país, que en estos momentos cumple 76 años de existencia. Caldas tuvo curiosidad por todo lo que existía en su entorno; inicialmente en su natal Popayán, donde se maravilló por lo natural, lo que lo motivó y llevó más allá de su tierra a formar parte de la mayor empresa de exploración científica adelantada en ese entonces en territorio americano: la primera Expedición Botánica al nuevo Reino de Granada, de José Celestino Mutis.

  13. Mortalidad por meningitis por Pasteurella canis. Oportunidades de aprendizaje

    Directory of Open Access Journals (Sweden)

    Ana Rosa Ropero Vera

    2016-01-01

    Full Text Available La meningitis bacteriana es una enfermedad importante de distribución mundial, causa mayor y sustancial de mortalidad y morbilidad en países en desarrollo. La Organización Mundial de la Salud (OMS sostiene que la meningitis es una de las diez afecciones principales del ser humano y debe ser considerada como una emergencia infectológica; por eso es fundamental reconocer que esta enfermedad es causa de muerte en niños de todo el mundo, sin distinción de raza, nivel económico o sociocultural. Se realizó una investigación de caso en menor de 53 días de nacido, que cumplía con los criterios clínicos y de laboratorio compatible con meningitis bacteriana, con el propósito de analizar y fortalecer la toma de decisiones en salud pública por parte de la secretaría local de salud del municipio de Valledupar (Colombia. Entre los hallazgos se encontró antecedentes infecciosos en el menor, coloración de Gram y cultivo de LCR, en el que se identificó cocobacilos Gram negativos, que fueron aislados como agente causal Pasteurella canis. Este estudio pretende sensibilizar a los prestadores de salud para que cuenten con personal altamente capacitado para brindar tratamientos adecuados y prevenir complicaciones en la meningitis bacteriana en niños, y así disminuir la posibilidad de secuelas o muerte, tanto en pacientes con compromiso inmunológico o sin este.

  14. Identification of heme oxygenase-1 stimulators by a convenient ELISA-based bilirubin quantification assay.

    Science.gov (United States)

    Rücker, Hannelore; Amslinger, Sabine

    2015-01-01

    The upregulation of heme oxygenase-1 (HO-1) has proven to be a useful tool for fighting inflammation. In order to identify new HO-1 inducers, an efficient screening method was developed which can provide new lead structures for drug research. We designed a simple ELISA-based HO-1 enzyme activity assay, which allows for the screening of 12 compounds in parallel in the setting of a 96-well plate. The well-established murine macrophage cell line RAW264.7 is used and only about 26µg of protein from whole cell lysates is needed for the analysis of HO-1 activity. The quantification of HO-1 activity is based on an indirect ELISA using the specific anti-bilirubin antibody 24G7 to quantify directly bilirubin in the whole cell lysate, applying a horseradish peroxidase-tagged antibody together with ortho-phenylenediamine and H2O2 for detection. The bilirubin is produced on the action of HO enzymes by converting their substrate heme to biliverdin and additional recombinant biliverdin reductase together with NADPH at pH 7.4 in buffer. This sensitive assay allows for the detection of 0.57-82pmol bilirubin per sample in whole cell lysates. Twenty-three small molecules, mainly natural products with an α,β-unsaturated carbonyl unit such as polyphenols, including flavonoids and chalcones, terpenes, an isothiocyanate, and the drug oltipraz were tested at typically 6 or 24h incubation with RAW264.7 cells. The activity of known HO-1 inducers was confirmed, while the chalcones cardamonin, flavokawain A, calythropsin, 2',3,4'-trihydroxy-4-methoxychalcone (THMC), and 2',4'-dihydroxy-3,4-dimethoxychalcone (DHDMC) were identified as new potent HO-1 inducers. The highest inductive power after 6h incubation was found at 10µM for DHDMC (6.1-fold), carnosol (3.9-fold), butein (3.1-fold), THMC (2.9-fold), and zerumbone (2.5-fold). Moreover, the time dependence of HO-1 protein production for DHDMC was compared to its enzyme activity, which was further evaluated in the presence of

  15. Development of an ELISA assay for screening inhibitors against divalent metal ion dependent alphavirus capping enzyme.

    Science.gov (United States)

    Kaur, Ramanjit; Mudgal, Rajat; Narwal, Manju; Tomar, Shailly

    2018-06-26

    Alphavirus non-structural protein, nsP1 has a distinct molecular mechanism of capping the viral RNAs than the conventional capping mechanism of host. Thus, alphavirus capping enzyme nsP1 is a potential drug target. nsP1 catalyzes the methylation of guanosine triphosphate (GTP) by transferring the methyl group from S-adenosylmethionine (SAM) to a GTP molecule at its N7 position with the help of nsP1 methyltransferase (MTase) followed by guanylylation (GT) reaction which involves the formation of m 7 GMP-nsP1 covalent complex by nsP1 guanylyltransferase (GTase). In subsequent reactions, m 7 GMP moiety is added to the 5' end of the viral ppRNA by nsP1 GTase resulting in the formation of cap0 structure. In the present study, chikungunya virus (CHIKV) nsP1 MTase and GT reactions were confirmed by an indirect non-radioactive colorimetric assay and western blot assay using an antibody specific for the m 7 G cap, respectively. The purified recombinant CHIKV nsP1 has been used for the development of a rapid and sensitive non-radioactive enzyme linked immunosorbent assay (ELISA) to identify the inhibitors of CHIKV nsP1. The MTase reaction is followed by GT reaction and resulted in m 7 GMP-nsP1 covalent complex formation. The developed ELISA nsP1 assay measures this m 7 GMP-nsP1 complex by utilizing anti-m 7 G cap monoclonal antibody. The mutation of a conserved residue Asp63 to Ala revealed its role in nsP1 enzyme reaction. Inductively coupled plasma mass spectroscopy (ICP-MS) was used to determine the presence of magnesium ions (Mg 2+ ) in the purified nsP1 protein. The divalent metal ion selectivity and investigation show preference for Mg 2+ ion by CHIKV nsP1. Additionally, using the developed ELISA nsP1 assay, the inhibitory effects of sinefungin, aurintricarboxylic acid (ATA) and ribavirin were determined and the IC 50 values were estimated to be 2.69 µM, 5.72 µM and 1.18 mM, respectively. Copyright © 2018. Published by Elsevier B.V.

  16. DPI-ELISA: a fast and versatile method to specify the binding of plant transcription factors to DNA in vitro

    Directory of Open Access Journals (Sweden)

    Chaban Christina

    2010-11-01

    Full Text Available Abstract Background About 10% of all genes in eukaryote genomes are predicted to encode transcription factors. The specific binding of transcription factors to short DNA-motifs influences the expression of neighbouring genes. However, little is known about the DNA-protein interaction itself. To date there are only a few suitable methods to characterise DNA-protein-interactions, among which the EMSA is the method most frequently used in laboratories. Besides EMSA, several protocols describe the effective use of an ELISA-based transcription factor binding assay e.g. for the analysis of human NFκB binding to specific DNA sequences. Results We provide a unified protocol for this type of ELISA analysis, termed DNA-Protein-Interaction (DPI-ELISA. Qualitative analyses with His-epitope tagged plant transcription factors expressed in E. coli revealed that EMSA and DPI-ELISA result in comparable and reproducible data. The binding of AtbZIP63 to the C-box and AtWRKY11 to the W2-box could be reproduced and validated by both methods. We next examined the physical binding of the C-terminal DNA-binding domains of AtWRKY33, AtWRKY50 and AtWRKY75 to the W2-box. Although the DNA-binding domain is highly conserved among the WRKY proteins tested, the use of the DPI-ELISA discloses differences in W2-box binding properties between these proteins. In addition to these well-studied transcription factor families, we applied our protocol to AtBPC2, a member of the so far uncharacterised plant specific Basic Pentacysteine transcription factor family. We could demonstrate binding to GA/TC-dinucleotide repeat motifs by our DPI-ELISA protocol. Different buffers and reaction conditions were examined. Conclusions We successfully applied our DPI-ELISA protocol to investigate the DNA-binding specificities of three different classes of transcription factors from Arabidopsis thaliana. However, the analysis of the binding affinity of any DNA-binding protein to any given DNA

  17. The use of antigen-detection ELISA for the diagnosis of bovine trypanosomosis in Cote d'Ivoire

    International Nuclear Information System (INIS)

    Kone, P.; Komoin-Oka, C.; N'Depo, A.

    1997-01-01

    An Antigen ELISA (Ag-ELISA) detecting circulating antigens of trypanosomes was evaluated in the central region of Cote d'Ivoire for the serodiagnosis of cattle trypanosomosis. Of 1423 sera examined, only 43 were positive in the MHCT/BCT, 105 (7%) were detected using stained blood smears, and 74 (5%) were found positive using the Ag-ELISA. The predominant trypanosome species was T. brucei, being present in 84% of the positive samples as detected by the BCT, in 96% using stained bloodsmears, and in 72% by Ag-ELISA. T.vivax was detected less frequently. The serological (ELISA) test did not detect all positive animals as found by the haematological techniques. However, the two techniques should be used in a complementary way to improve the diagnosis of the disease. The results confirm that the prevalence of trypanosomes in cattle is low in the study area. The low prevalence can be due to prophylaxis and therapy of livestock in combination with successful tsetse trapping. (author). 4 refs, 2 figs, 4 tabs

  18. Novel indirect enzyme-linked immunosorbent assay (ELISA) method to detect Total E. coli in water environment

    International Nuclear Information System (INIS)

    Wang Na; He Miao; Shi Hanchang

    2007-01-01

    In order to establish ELISA (enzyme-linked immunosorbent assay) method to detect Total E. coli in water environment, E. coli multi-characters antigens in water environment were prepared according to the characters of kinds of E. coli serotypes, including antigen of whole cell, antigen of disrupted whole cell, somatic antigen, flagellar antigen and fimbrial antigen. Total E. coli polyclonal antibodies were obtained from the New Zealand rabbits immunized with these five antigens, respectively. Antibodies generated in this research are with high titers and good purity, can conjugate with antigens, specifically, stably and strongly. Indirect ELISA shows the titers of antibody of whole cell and antibody of disrupted whole cell are both over 1 x 10 5 . The cross-reactivity of the antibody is from 12 to 30% which indicate the specificity of the antibody against Total E. coli. Based on these antibodies, we established indirect ELISA method to detect Total E. coli in water environment. The matrix effects were studied and the results show that there is no significant influence by all the factors. The ELISA result shows that the detection limitation could be 10 4 CFU (colony forming units) L -1 . The indirect ELISA method developed in this study is well suited for Total E. coli analysis in real water samples as a rapid screen method

  19. Influence of baking time and matrix effects on the detection of milk allergens in cookie model food system by ELISA.

    Science.gov (United States)

    Monaci, Linda; Brohée, Marcel; Tregoat, Virginie; van Hengel, Arjon

    2011-07-15

    Milk allergens are common allergens occurring in foods, therefore raising concern in allergic consumers. Enzyme-linked immunosorbent assay (ELISA) is, to date, the method of choice for the detection of food allergens by the food industry although, the performance of ELISA might be compromised when severe food processing techniques are applied to allergen-containing foods. In this paper we investigated the influence of baking time on the detection of milk allergens by using commercial ELISA kits. Baked cookies were chosen as a model food system and experiments were set up to study the impact of spiking a matrix food either before, or after the baking process. Results revealed clear analytical differences between both spiking methods, which stress the importance of choosing appropriate spiking methodologies for method validation purposes. Finally, since the narrow dynamic range of quantification of ELISA implies that dilution of samples is required, the impact of sample dilution on the quantitative results was investigated. All parameters investigated were shown to impact milk allergen detection by means of ELISA. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. The use of antigen-detection ELISA for the diagnosis of bovine trypanosomosis in Cote d`Ivoire

    Energy Technology Data Exchange (ETDEWEB)

    Kone, P [Laboratoire Regional de Pathologie Animale de Bouake (LANADA), Bouake (Cote d` Ivoire); Komoin-Oka, C; N` Depo, A [Laboratoire Central de Pathologie Animale de Bingerville (LANADA), Bingerville (Cote d` Ivoire)

    1997-02-01

    An Antigen ELISA (Ag-ELISA) detecting circulating antigens of trypanosomes was evaluated in the central region of Cote d`Ivoire for the serodiagnosis of cattle trypanosomosis. Of 1423 sera examined, only 43 were positive in the MHCT/BCT, 105 (7%) were detected using stained blood smears, and 74 (5%) were found positive using the Ag-ELISA. The predominant trypanosome species was T. brucei, being present in 84% of the positive samples as detected by the BCT, in 96% using stained bloodsmears, and in 72% by Ag-ELISA. T.vivax was detected less frequently. The serological (ELISA) test did not detect all positive animals as found by the haematological techniques. However, the two techniques should be used in a complementary way to improve the diagnosis of the disease. The results confirm that the prevalence of trypanosomes in cattle is low in the study area. The low prevalence can be due to prophylaxis and therapy of livestock in combination with successful tsetse trapping. (author). 4 refs, 2 figs, 4 tabs.

  1. Detection of thyroid stimulating hormone receptor antibodies (TRAb) by radioreceptor assay (RRA) and enzyme-linked immunosorbent assay (ELISA)

    International Nuclear Information System (INIS)

    Dumrongpisutikul, S.; Tuchinda, S.

    1990-01-01

    Thyroid stimulating hormone receptor antibodies (TRAb) were determined in 100 patients using radioreceptor assay (RRA) and enzyme-linked immunosorbent assay (ELISA). The sensitivity of RRA and ELISA were found to be 70.6% and 88.2% respectively (n=51). The specificity of both assays were 100% (n=16). With RRA as the standard test the sensitivity and specificity of ELISA were 75.8% and 86.8%. In the untreated hyperthyroid the RRA result which expressed as % specific 125 I-TSH inhibition was 33.6% (n=51), decline to 26.9% in the treated hyperthyroid (n=33) and 14.1% in the euthyroid (n=16). The mean 0.D 492nm of TRAb-ELISA were 0.861 in untreated hyperthyroid, 0.437 in treated hyperthyroid and 0.135 in euthyroid Phi coefficient analysis show that the RRA was 60.4% correlated to hyperthyroidism where as TRAb-ELISA was 80.1%

  2. Undressing of Waddlia chondrophila to enrich its outer membrane proteins to develop a new species-specific ELISA

    Directory of Open Access Journals (Sweden)

    J. Lienard

    2014-01-01

    Full Text Available Waddlia chondrophila, an obligate intracellular bacterium of the Chlamydiales order, is considered as an agent of bovine abortion and a likely cause of miscarriage in humans. Its role in respiratory diseases was questioned after the detection of its DNA in clinical samples taken from patients suffering from pneumonia or bronchiolitis. To better define the role of Waddlia in both miscarriage and pneumonia, a tool allowing large-scale serological investigations of Waddlia seropositivity is needed. Therefore, enriched outer membrane proteins of W. chondrophila were used as antigens to develop a specific ELISA. After thorough analytical optimization, the ELISA was validated by comparison with micro-immunofluorescence and it showed a sensitivity above 85% with 100% specificity. The ELISA was subsequently applied to human sera to specify the role of W. chondrophila in pneumonia. Overall, 3.6% of children showed antibody reactivity against W. chondrophila but no significant difference was observed between children with and without pneumonia. Proteomic analyses were then performed using mass spectrometry, highlighting members of the outer membrane protein family as the dominant proteins. The major Waddlia putative immunogenic proteins were identified by immunoblot using positive and negative human sera. The new ELISA represents an efficient tool with high throughput applications. Although no association with pneumonia and Waddlia seropositivity was observed, this ELISA could be used to specify the role of W. chondrophila in miscarriage and in other diseases.

  3. Characterization of ELISA Antibody-Antigen Interaction using Footprinting-Mass Spectrometry and Negative Staining Transmission Electron Microscopy

    Science.gov (United States)

    Lin, Margaret; Krawitz, Denise; Callahan, Matthew D.; Deperalta, Galahad; Wecksler, Aaron T.

    2018-05-01

    We describe epitope mapping data using multiple covalent labeling footprinting-mass spectrometry (MS) techniques coupled with negative stain transmission electron microscopy (TEM) data to analyze the antibody-antigen interactions in a sandwich enzyme-linked immunosorbant assay (ELISA). Our hydroxyl radical footprinting-MS data using fast photochemical oxidation of proteins (FPOP) indicates suppression of labeling across the antigen upon binding either of the monoclonal antibodies (mAbs) utilized in the ELISA. Combining these data with Western blot analysis enabled the identification of the putative epitopes that appeared to span regions containing N-linked glycans. An additional structural mapping technique, carboxyl group footprinting-mass spectrometry using glycine ethyl ester (GEE) labeling, was used to confirm the epitopes. Deglycosylation of the antigen resulted in loss of potency in the ELISA, supporting the FPOP and GEE labeling data by indicating N-linked glycans are necessary for antigen binding. Finally, mapping of the epitopes onto the antigen crystal structure revealed an approximate 90° relative spatial orientation, optimal for a noncompetitive binding ELISA. TEM data shows both linear and diamond antibody-antigen complexes with a similar binding orientation as predicted from the two footprinting-MS techniques. This study is the first of its kind to utilize multiple bottom-up footprinting-MS techniques and TEM visualization to characterize the monoclonal antibody-antigen binding interactions of critical reagents used in a quality control (QC) lot-release ELISA. [Figure not available: see fulltext.

  4. Development of enzyme linked immunosorbent assay (ELISA) for the detection of root-knot nematode Meloidogyne incognita.

    Science.gov (United States)

    Kapur-Ghai, J; Kaur, M; Goel, P

    2014-09-01

    Root-knot nematodes (Meloidogyne incognita) are obligate, sedentary plant endoparasites that are extremely polyphagous in nature and cause severe economic losses in agriculture. Hence, it is essential to control the parasite at an early stage. For any control strategy to be effective, an early and accurate diagnosis is of paramount importance. Immunoassays have the inherent advantages of sensitivity and specificity; have the potential to identify and quantify these plant-parasitic nematodes. Hence, in the present studies, enzyme-linked immunosorbent assay (ELISA) has been developed for the detection of M.incognita antigens. First an indirect ELISA was developed for detection and titration of anti-M.incognita antibodies. Results indicated as high as 320 K titre of the antisera. Finally competitive inhibition ELISA was developed employing these anti-M.incognita antibodies for detection of M.incognita antigens. Sensitivity of ELISA was 10 fg. Competitive inhibition ELISA developed in the present studies has the potential of being used as an easy, rapid, specific and sensitive diagnostic tool for the detection of M.incognita infection.

  5. Commercial Milk Enzyme-Linked Immunosorbent Assay (ELISA) Kit Reactivities to Purified Milk Proteins and Milk-Derived Ingredients.

    Science.gov (United States)

    Ivens, Katherine O; Baumert, Joseph L; Taylor, Steve L

    2016-07-01

    Numerous commercial enzyme-linked immunosorbent assay (ELISA) kits exist to quantitatively detect bovine milk residues in foods. Milk contains many proteins that can serve as ELISA targets including caseins (α-, β-, or κ-casein) and whey proteins (α-lactalbumin or β-lactoglobulin). Nine commercially-available milk ELISA kits were selected to compare the specificity and sensitivity with 5 purified milk proteins and 3 milk-derived ingredients. All of the milk kits were capable of quantifying nonfat dry milk (NFDM), but did not necessarily detect all individual protein fractions. While milk-derived ingredients were detected by the kits, their quantitation may be inaccurate due to the use of different calibrators, reference materials, and antibodies in kit development. The establishment of a standard reference material for the calibration of milk ELISA kits is increasingly important. The appropriate selection and understanding of milk ELISA kits for food analysis is critical to accurate quantification of milk residues and informed risk management decisions. © 2016 Institute of Food Technologists®

  6. Characterization of ELISA Antibody-Antigen Interaction using Footprinting-Mass Spectrometry and Negative Staining Transmission Electron Microscopy

    Science.gov (United States)

    Lin, Margaret; Krawitz, Denise; Callahan, Matthew D.; Deperalta, Galahad; Wecksler, Aaron T.

    2018-03-01

    We describe epitope mapping data using multiple covalent labeling footprinting-mass spectrometry (MS) techniques coupled with negative stain transmission electron microscopy (TEM) data to analyze the antibody-antigen interactions in a sandwich enzyme-linked immunosorbant assay (ELISA). Our hydroxyl radical footprinting-MS data using fast photochemical oxidation of proteins (FPOP) indicates suppression of labeling across the antigen upon binding either of the monoclonal antibodies (mAbs) utilized in the ELISA. Combining these data with Western blot analysis enabled the identification of the putative epitopes that appeared to span regions containing N-linked glycans. An additional structural mapping technique, carboxyl group footprinting-mass spectrometry using glycine ethyl ester (GEE) labeling, was used to confirm the epitopes. Deglycosylation of the antigen resulted in loss of potency in the ELISA, supporting the FPOP and GEE labeling data by indicating N-linked glycans are necessary for antigen binding. Finally, mapping of the epitopes onto the antigen crystal structure revealed an approximate 90° relative spatial orientation, optimal for a noncompetitive binding ELISA. TEM data shows both linear and diamond antibody-antigen complexes with a similar binding orientation as predicted from the two footprinting-MS techniques. This study is the first of its kind to utilize multiple bottom-up footprinting-MS techniques and TEM visualization to characterize the monoclonal antibody-antigen binding interactions of critical reagents used in a quality control (QC) lot-release ELISA. [Figure not available: see fulltext.

  7. Application of Microwave Irradiation and Heat to Improve Gliadin Detection and Ricin ELISA Throughput with Food Samples

    Directory of Open Access Journals (Sweden)

    Eric A. E. Garber

    2015-06-01

    Full Text Available The utility of microwave irradiation to accelerate the onset of equilibrium and improve ELISA performance was examined using ELISAs for the detection of the plant toxin ricin and gliadin. The ricin ELISA normally requires several one hour incubations at 37 °C, a total assay time of approximately five hours, and employs a complex buffer containing PBS, Tween-20®, and non-fat milk. Different energy levels and pulse designs were compared to the use of abbreviated incubation times at 37 °C for the detection of ricin in food. The use of microwave irradiation had no significant advantage over the application of heat using an oven incubator and performed worse with some foods. In contrast, a gliadin ELISA that relied on 30 min incubation steps at room temperature and a salt-based buffer performed better upon irradiation but also displayed improvement upon incubating the microtiter plate at 37 °C. Whether microwave irradiation was advantageous compared to incubation in an oven was inconclusive. However, by abbreviating the incubation time of the ricin ELISA, it was possible to cut the assay time to less than 2 hours and still display LOD values < 10 ppb and recoveries of 78%–98%.

  8. Comparative evaluation of antibody positive titer by ELISA and IFA in Theileria annulata vaccinated cattle in Iran

    Directory of Open Access Journals (Sweden)

    Hashemi-Fesharki R.

    2006-03-01

    Full Text Available An enzyme linked immunosorbent assay (ELISA was used to evaluate antibody positive titer in vaccinated and non-vaccinated cattle using schizont infected myeloid cells as an antigen. The result was compared with indirect fluorescent antibody level in the same animals. For this study 116 milking cows, 95 vaccinated and 21 non-vaccinated, were bleeded in order to prepare sera. They were tested with both ELISA and IFA tests. 94 sera had positive antibody titer and 22 sera were negative through ELISA test but, with IFA test, only 89 sera showed positive antibody titer and 27 were negative. Thereby, it was concluded that the sensitivity and specificity of ELISA test in comparison with IFA test was 95.5 % and 66.6 % respectively. This study generally indicated that ELISA could be an effective test for seroepidemiological investigations of bovine tropical theileriosis, and it is considered to be valid as an additional test to distinguish the vaccinated from the non vaccinated cattle in order to schedule vaccination programs.

  9. Development of a sensitive and specific epitope-blocking ELISA for universal detection of antibodies to human enterovirus 71 strains.

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    Fang He

    Full Text Available BACKGROUND: Human Enterovirus 71 (EV71 is a common cause of hand, foot and mouth disease (HFMD in young children. It is often associated with severe neurological diseases and mortalities in recent outbreaks across the Asia Pacific region. Currently, there is no efficient universal antibody test available to detect EV71 infections. METHODOLOGY/PRINCIPAL FINDING: In the present study, an epitope-blocking ELISA was developed to detect specific antibodies to human EV71 viruses in human or animal sera. The assay relies on a novel monoclonal antibody (Mab 1C6 that specifically binds to capsid proteins in whole EV71 viruses without any cross reaction to any EV71 capsid protein expressed alone. The sensitivity and specificity of the epitope-blocking ELISA for EV71 was evaluated and compared to microneutralization using immunized animal sera to multiple virus genotypes of EV71 and coxsackieviruses. Further, 200 serum sample from human individuals who were potentially infected with EV71 viruses were tested in both the blocking ELISA and microneutralization. Results indicated that antibodies to EV71 were readily detected in immunized animals or human sera by the epitope blocking ELISA whereas specimens with antibodies to other enteroviruses yielded negative results. This assay is not only simpler to perform but also shows higher sensitivity and specificity as compared to microneutralization. CONCLUSION: The epitope-blocking ELISA based on a unique Mab 1C6 provided highly sensitive and 100% specific detection of antibodies to human EV71 viruses in human sera.

  10. ELISA test for the diagnosis of cysticercosis in pigs using antigens of Taenia solium and Taenia crassiceps cysticerci Teste ELISA para diagnóstico da cisticercose suína usando antígenos de larvas de Taenia solium e Taenia crassiceps

    Directory of Open Access Journals (Sweden)

    Paulo Sérgio de Arruda PINTO

    2000-04-01

    Full Text Available In the present study ELISA was standardized for the diagnosis of swine cysticercosis based on necropsy parameters and confirmed positive and negative control sera. Serum samples from pigs with other infections were also assayed to determine possible cross-reactions. Four antigens were assayed: from Taenia crassiceps vesicular fluid (VF-Tcra and crude larvae extract (T-Tcra, and from Taenia solium extracts of scolex (S-Ts and of larvae (T-Ts. A checkerboard evaluation of antigen, serum and conjugate dilutions, as well as the use of Tween-20 and skim cow milk in wash and blocking solution had a marked effect on improving ELISA performance. All the antigens showed a good performance, but VF-Tcra was the best, with 96.0% and 80.0% sensitivities for cut-offs respectively at 2sd and 3sd, and corresponding specificities of 97.5% and 100.0%. Cross-reactivity was observed only with hydatidosis and ascaridiosis. In view of the high performance observed, the ELISA test should be recommended for the diagnosis of cysticercosis in suspected swine in slaughterhouses and for the screening of cysticercosis in swine production. These results will support integrated measures of cysticercosis control throughout the chain of swine production, effectively contributing to public health.Foi padronizado o teste ELISA para o diagnóstico da cisticercose suína. Após confirmação por exame post-mortem, os soros dos respectivos animais foram empregados como controles positivos e negativos. Soros de suínos portadores de infecções heterólogas foram ensaiados para determinação de reações cruzadas. Os quatro antígenos testados na fase de padronização foram líquido vesicular (VF e extrato total (T de larvas de Taenia crassiceps (Tcra e de extrato de escólex (S e de cisticercos (T de Taenia solium (Tso. A titulação em bloco das ótimas concentrações de antígenos e diluições de soros e de conjugado, bem como o emprego de Tween-20 e de leite desnatado nas

  11. Mortalidad intrahospitalaria por accidente cerebrovascular

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    Federico Rodríguez Lucci

    2013-08-01

    Full Text Available La mortalidad global por accidente cerebrovascular (ACV ha disminuido en las últimas tres décadas, probablemente debido a un mejor control de los factores de riesgo vascular. La mortalidad hospitalaria por ACV ha sido tradicionalmente estimada entre 6 y 14% en la mayoría de las series comunicadas. Sin embargo, los datos de ensayos clínicos recientes sugieren que esta cifra sería sustancialmente menor. Se revisaron datos de pacientes internados con diagnóstico de ACV del Banco de Datos de Stroke de FLENI y los registros institucionales de mortalidad entre los años 2000 y 2010. Los subtipos de ACV isquémicos se clasificaron según criterios TOAST y los ACV hemorrágicos en hematomas intrapanquimatosos, hemorragias subaracnoideas aneurismáticas, malformaciones arteriovenosas y otros hematomas intraparenquimatosos. Se analizaron 1514 pacientes, 1079 (71% con ACV isquémico (grandes vasos 39%, cardioembólicos 27%, lacunares 9%, etiología indeterminada 14%, otras etiologías 11% y 435 (29% con ACV hemorrágico (intraparenquimatosos 27%, hemorragia subaracnoidea 30%, malformaciones arteriovenosas 25% y otros hematomas espontáneos 18%. Se registraron 38 muertes intrahospitalarias (17 ACV isquémicos y 21 ACV hemorrágicos, representando una mortalidad global del 2.5% (1.7% en ACV isquémicos y 4.8% en ACV hemorrágicos. No se registraron muertes asociadas al uso de fibrinolíticos endovenosos. La mortalidad intrahospitalaria en pacientes con ACV isquémico y hemorrágico en nuestro centro fue baja. El manejo en un centro dedicado a las enfermedades neurológicas y el enfoque multidisciplinario por personal médico y no médico entrenado en el cuidado de la enfermedad cerebrovascular podrían explicar, al menos en parte, estos resultados.

  12. Application of 60Co γ-ray irradiated polystyrene microplate for anti-HCV ELISA

    International Nuclear Information System (INIS)

    Feng Bo; Zeng Hongyan; Tang Yufang; Wang Lu

    2005-01-01

    In order to explore the effect of 60 Co γ-ray irradiation on minor polypeptides absorption of polystyrene microplate, an indirect ELISA detection of anti-HCV was established, 60 Co γ-ray irradiated polystyrene microplates and the controls (without irradiation or UV-irradiated) were applied to absorb recombinant HCV antigens respectively. Cooperated with Bovine antihuman IgG labelled HRP, their related indices of sensitivity, specificity, homogeneity and stability were determinate. The results indicated that, optimum dose of the γ-ray irradiation is 8 kGy, and compared with the controls, detection sensitivity and homogeneity of the polystyrene microplate irradiated to 8 kGy could be improved markedly. (authors)

  13. Evaluation of ELISA screening test for detecting aflatoxin in biogenic dust samples

    Energy Technology Data Exchange (ETDEWEB)

    Durant, J.T.

    1996-05-01

    Aflatoxin is a carcinogenic chemical that is sometimes produced when agricultural commodities are infested by the fungi Aspergillus flavus and A. Parasiticus. Aflatoxin has been found to be present in air samples taken around persons handling materials likely to be contaminated. The purpose of this investigation was to demonstrate the feasibility of using an Enzyme Linked Immunosorbent Assay (ELISA) test kit that was developed to screen for aflatoxin in bulk agricultural commodities, to an air sample. Samples were taken from two environments likely to be contaminated with aflatoxin, a dairy farm feed mixing operation and a peanut bagging operation. The dust collected from these environments was considered to be biogenic, in that it originated primarily from biological materials.

  14. Penggunaan Crude Antigen Cysticercus cellulosae Isolat Bali Untuk Optimalisasi Uji ELISA

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    Inti Sari Pati R U Sianturi

    2017-01-01

    Full Text Available Sistiserkosis merupakan penyakit parasitik yang disebabkan oleh larva stadium metacestoda dari cacing pita yang disebut Cysticercus.  Cysticercus yang ditemukan pada babi adalah Cysticercus cellulosae yang merupakan larva dari cacing pita Taenia solium. Penelitian ini dilakukan dengan tujuan mengevaluasi antigen crude Cysticercus cellulosae untuk mendeteksi sistiserkosis pada babi. Cysticercus celllulosae yang digunakan adalah isolat lokal yang diperoleh dari babi terinfeksi Taenia solium asal Karangasem-Bali. Penelitian dilakukan untuk optimalisasi ELISA (Enzyme Linked Immunosorbent Assay terhadap antigen, serum, dan konjugat dengan cara mencari konsentrasi optimal dari antigen, pengenceran optimal serum, dan pengenceran optimal konjugat. Hasil penelitian didapatkan bahwa crude antigen Cysticercus cellulosae isolat Bali bersifat antigenik dan dapat digunakan untuk mendeteksi sistiserkosis pada babi dengan konsentrasi optimal antigen 0,3125 µg/ml, pengenceran optimal serum 1:50, dan pengenceran konjugat 1:2000.

  15. The rapid identification of human influenza neuraminidase N1 and N2 subtypes by ELISA.

    Science.gov (United States)

    Barr, I G; McCaig, M; Durrant, C; Shaw, R

    2006-11-10

    An ELISA assay was developed to allow the rapid and accurate identification of human influenza A N1 and N2 neuraminidases. Initial testing using a fetuin pre-coating of wells correctly identified 81.7% of the neuraminidase type from a series of human A(H1N1), A(H1N2) and A(H3N2) viruses. This result could be improved to detect the neuraminidase subtype of almost all human influenza A viruses from a large panel of viruses isolated from 2000 to 2005, if the fetuin pre-coating was removed and the viruses were coated directly onto wells. This method is simple, rapid and can be used to screen large numbers of currently circulating human influenza A viruses for their neurraminidase subtype and is a good alternative to RT-PCR.

  16. Effect of processing on the detectability of peanut protein by ELISA.

    Science.gov (United States)

    Iqbal, Amjad; Ateeq, Nadia

    2013-12-01

    Chicken IgY was used for the detection and quantification of peanut proteins by indirect competitive ELISA. The method was optimized by using a checker board approach to determine the optimal concentration of coating antigen, primary antibody and secondary antibody. Peanut protein could be detected in foods down to levels of 10 ppm. The effect of physical (heat treatment at 80 °C and 100 °C) and chemical (acid, alkali and reducing sugar) treatments on the IgY binding of peanut proteins was investigated. The optimized assay was relatively sensitive for the roasted peanut proteins. However, the binding ability of chicken IgYs to peanut proteins was found to be significantly altered by denaturation and hydrolysis of proteins. It was also observed that the effect of Millard chemistry on the detectability of peanut protein was less pronounced at high temperatures than at low temperatures. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Detection of helicobacter pylori in nasal polyps using rapid urease test and ELISA

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    Masood Kaviani

    2009-01-01

    Full Text Available Introduction: Nasal polyposis is an inflammatory condition of unknown etiology. Recently concerns regarding gastroesophageal reflux or helicobacter pylori as a possible pathologic cause of nasal polyps have been increasing. The present study was planned to investigate the presence of helicobacter pylori in nasal polyps. Materials and Methods: This case-control study was undertaken enrolling 37 patients with nasal polyps who had undergone nasal endoscopic sinus surgery and 38 control subjects. Biopsy specimens of nasal polyps and inferior turbinates were assessed by rapid urease test. Blood samples of both study and control subjects were evaluated for anti H.pylori IgG by ELISA. H. pylori status was regarded positive, if both tests were positive. Results: Seropositivity was more common in the patients with nasal polyps (66.2% than control subjects (36.8% (P

  18. eLISA Telescope In-field Pointing and Scattered Light Study

    Science.gov (United States)

    Livas, J.; Sankar, S.; West, G.; Seals, L.; Howard, J.; Fitzsimons, E.

    2017-05-01

    The orbital motion of the three spacecraft that make up the eLISA Observatory constellation causes long-arm line of sight variations of approximately ± one degree over the course of a year. The baseline solution is to package the telescope, the optical bench, and the gravitational reference sensor (GRS) into an optical assembly at each end of the measurement arm, and then to articulate the assembly. An optical phase reference is exchanged between the moving optical benches with a single mode optical fiber (“backlink” fiber). An alternative solution, referred to as in-field pointing, embeds a steering mirror into the optical design, fixing the optical benches and eliminating the backlink fiber, but requiring the additional complication of a two-stage optical design for the telescope. We examine the impact of an in-field pointing design on the scattered light performance.

  19. Determination of serum DNA concentration by enzyme immunoassay (ELISA) in gamma irradiated rats

    Energy Technology Data Exchange (ETDEWEB)

    Gabor, J; Misurova, E

    1987-01-01

    A sensitive and specific ELISA method was used to determine changes in the serum DNA concentration in rats at hours 6 and 9 and on the days 1, 3, 7, 10, 15 and 30 after acute whole-body gamma irradiation with a dose of 8 Gy. Changes in the DNA serum concentration were determined also on day 10 after irradiation with doses of 4, 6, 8, 10 and 12 Gy. The present results indicate that the pattern of changes in the serum DNA concentration is characterized by an initial decrease, typical also of the leukocyte count, followed by a statistically significant increase in the DNA concentration on day 10 and in later periods of time. These data confirmed, in principle, the authors' previous findings on changes in the DNA concentration in the rat blood plasma after acute X-ray irradiation assessed by the fluorimetric method with ethidium bromide. (author). 4 figs., 14 refs.

  20. Possible Periodic Orbit Control Maneuvers for an eLISA Mission

    Science.gov (United States)

    Bender, Peter L.; Welter, Gary L.

    2012-01-01

    This paper investigates the possible application of periodic orbit control maneuvers for so-called evolved-LISA (eLISA) missions, i.e., missions for which the constellation arm lengths and mean distance from the Earth are substantially reduced. We find that for missions with arm lengths of 106 km and Earth-trailing distance ranging from approx. 12deg to 20deg over the science lifetime, the occasional use of the spacecraft micro-Newton thrusters for constellation configuration maintenance should be able to essentially eliminate constellation distortion caused by Earth-induced tidal forces at a cost to science time of only a few percent. With interior angle variation kept to approx. +/-0:1deg, the required changes in the angles between the laser beam pointing directions for the two arms from any spacecraft could be kept quite small. This would considerably simplify the apparatus necessary for changing the transmitted beam directions.

  1. Incorporation of the ELISA technique to determine antibody levels against foot-and-mouth disease

    International Nuclear Information System (INIS)

    Vergara, N.N.; Caballero, P.H.; Santiago Gonzalez Patino, S.; Orue, P.M.

    1998-01-01

    Two groups of sera were evaluated by a liquid phase blocking ELISA (LPBE) for the detection and quantification of foot-and-mouth disease (FMD) antibodies to serotypes O, A and C to assess the sensitivity and specificity of the assay. The first group consisted of 120 sera from non-infected and non-vaccinated cattle, which were tested by a screening assay at a fix dilution of 1/32. The second group consisted of 120 sera from cattle vaccinated with a trivalent (O, A and C) vaccine. Sera from this group were titrated in a five fold dilution range: 1/10, 1/50, 1/250 and 1/1250. (author)

  2. Validation of a KHV antibody enzyme-linked immunosorbent assay (ELISA).

    Science.gov (United States)

    Bergmann, S M; Wang, Q; Zeng, W; Li, Y; Wang, Y; Matras, M; Reichert, M; Fichtner, D; Lenk, M; Morin, T; Olesen, N J; Skall, H F; Lee, P-Y; Zheng, S; Monaghan, S; Reiche, S; Fuchs, W; Kotler, M; Way, K; Bräuer, G; Böttcher, K; Kappe, A; Kielpinska, J

    2017-11-01

    Koi herpesvirus (KHV) causes KHV disease (KHVD). The virus is highly contagious in carp or koi and can induce a high mortality. Latency and, in some cases, a lack of signs presents a challenge for virus detection. Appropriate immunological detection methods for anti-KHV antibodies have not yet been fully validated for KHV. Therefore, it was developed and validated an enzyme-linked immunosorbent assay (ELISA) to detect KHV antibodies. The assay was optimized with respect to plates, buffers, antigens and assay conditions. It demonstrated high diagnostic and analytical sensitivity and specificity and was particularly useful at the pond or farm levels. Considering the scale of the carp and koi industry worldwide, this assay represents an important practical tool for the indirect detection of KHV, also in the absence of clinical signs. © 2017 John Wiley & Sons Ltd.

  3. DISKRIMINASI KELAMIN PADA IKAN TUNA SIRIP KUNING, Yellowfin tuna MENGGUNAKAN ANALISIS DOT BLOT DAN ELISA

    Directory of Open Access Journals (Sweden)

    Gusti Ngurah Permana

    2014-08-01

    Full Text Available Pemahaman tentang penentuan jenis kelamin dalam populasi induk merupakan hal yang sangat penting bagi keberhasilan program pembenihan. Pengukuran reaksi antibodi dan aktivitas hormon testosterone, serta estradiol adalah metode dengan potensi yang secara akurat dapat menentukan jenis kelamin ikan tanpa mematikan ikan. Tujuan penelitian ini adalah untuk mengetahui akurasi metode dot blot dan ELISA dengan 11-ketotestorsterone (11-KT yang tersedia secara komersial EIA-kit untuk membedakan jenis kelamin ikan tuna sirip kuning. Hasil analisis menunjukkan bahwa metode dot blot menghasilkan ekspresi vitelogenin tampak jelas pada individu betina dan efek plasma terlihat transparan, jika dibandingkan dengan individu jantan. Interpretasi dari metode ini memerlukan pengalaman dan keahlian dalam akurasi pembacaan hasil. Aktivitas hormon 11-KT dengan sampel klip sirip dan plasma memberikan hasil yang baik dengan aktivitas hormon terlihat jelas.

  4. ELISA Ureasa para selección primaria y monitoreo de anticuerpos monoclonales

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    Gladys Thalía Cortes

    1990-12-01

    Full Text Available Se empleó el método de Elisa Ureasa indirecto para detectar anticuerpos monoclonales obtenidos a partir de ratones inmunizados con merozoítos libres de Plasmodium falciparum. Se seleccionaron los anticuerpos monoclonales que mostraron ser muy estables en posteriores ensayos de caracterización. Los anticuerpos obtenidos no fueron específiCos contra antígeno de Plasmodium falciparum pero permitieron identificar la proteína Espectrina del citoesqueleto de eritrocito humano. En el ensayo fue empleado un antígeno de esquizontes concentrados y solubilizados. Se obtuvo la determinación del punto final de la reacción a través de lectura visual semicuantitativa. A partir de la enzima Ureasa de alta pureza que se encuentra disponible comercialmente y, empleando métodos muy sencillos se prepararon los reactivos utilizados en el ensayo.

  5. The use of monoclonal antibodies in competitive ELISA for the detection of antibodies to rinderpest and peste des petits ruminants viruses

    International Nuclear Information System (INIS)

    Anderson, J.; McKay, J.A.; Butcher, R.N.

    1991-01-01

    A monoclonal antibody against the haemagglutinin of rinderpest virus has been used in a competitive ELISA (C-ELISA) for the detection of antibodies to rinderpest virus in cattle, sheep, goat and game sera. Unlike the indirect ELISA and the virus neutralisation test (VNT), the C-ELISA detects only antibodies to rinderpest virus and gives no cross-reactivity with antibodies to peste des petits ruminants (PPR) virus. Antibodies to a wide range of strains of rinderpest virus have been detected using this assay, suggesting its suitability for both sero-monitoring and sero-surveillance. Analysis of C-ELISA results from the examination of field sera shows a much greater separation of negative and positive populations as compared to the indirect ELISA. A further monoclonal antibody against the H protein of PPR has also been found suitable for use in a C-ELISA for the detection of antibodies to PPR virus. The use of these two C-ELISA's has made possible rapid differential sero-diagnosis without recourse to cross-VNT testing. The use of monoclonal antibody-based assays will allow much greater standardisation of rinderpest and PPR diagnosis, and following field-trials the C-ELISA will replace the indirect ELISA for sero-monitoring throughout the Pan African Rinderpest Campaign. (author). 3 refs, 6 figs, 1 tab

  6. Seroprevalence of Mycoplasma gallisepticum antibody by ELISA and serum plate agglutination test of laying chicken

    Directory of Open Access Journals (Sweden)

    Md. Zulfekar Ali

    2015-01-01

    Full Text Available Aim: Mycoplasma gallisepticum (MG is important avian pathogen responsible for chronic respiratory disease of chicken and turkeys, which result in large economic loss for the poultry industry. The objectives of this study were determination of seroprevalence of MG antibody of commercial layer chicken at laying period in selected areas of Bangladesh. Materials and Methods: A total of 563 blood samples were collected randomly from selected commercial layer chickens at laying period during the period from July to December, 2013. Indirect enzyme linked immunosorbent assay (iELISA and serum plate agglutination (SPA test were performed to detect the presence of antibodies against MG. Results: Of 563 samples, 64.47% and 56.13% showed an overall prevalence of MG antibodies in iELISA and SPA test respectively. Prevalence of MG was recorded the highest (69.63% at 50-55 weeks of age compared with lowest (53.26% at 56-61 weeks of age (p<0.05. Significant (p<0.05 effect of breed were observed in the seroprevalence of MG infection in layer birds in the present study. The overall, 68.77%, 63.74% and 59.37% prevalence were found respectively in sonali, ISA Brown and White leg horn. The prevalence of MG antibodies was the highest (70.13% in December followed by November (68%, October (65.67%, August (63.46%, September (58.54% and July (51.78% month. The seroprevalence of MG antibodies was higher (69.63% in most of the large flocks and lower (56.82% in small flocks. Conclusion: Therefore, might be suggested that the commercial layer farms should be routinely checked to monitor MG infection and the reactor birds should be culled since MG organism has the potential to transmit vertically. The correlation between MG antibody in month and flock size was not significant (p=0.359 and p=0.868, respectively.

  7. Added value of antigen ELISA in the diagnosis of neurocysticercosis in resource poor settings.

    Directory of Open Access Journals (Sweden)

    Sarah Gabriël

    Full Text Available BACKGROUND: Neurocysticercosis (NCC is the most common cause of acquired epilepsy in Taenia solium endemic areas, primarily situated in low-income countries. Diagnosis is largely based upon the "Del Brutto diagnostic criteria" using the definitive/probable/no NCC diagnosis approach. Neuroimaging and specific T. solium cysticercosis antibody detection results are at the mainstay of this diagnosis, while antigen detection in serum has never been included. This study aimed at evaluating the addition of antigen detection as a major diagnostic criterion, especially in areas where neuroimaging is absent. METHODS: The B158/B60 monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA for the detection of circulating cysticercus antigen was carried out retrospectively on serum samples collected during a hospital-based study from 83 people with epilepsy (PWE in an endemic area. RESULTS: The addition of antigen results as a major criterion allowed the correct diagnosis of definitive NCC in 10 out of 17 patients as opposed to 0/17 without antigen results in the absence of neuroimaging. A sensitivity of 100% and a specificity of 84% were determined for the diagnosis of active NCC using antigen ELISA. While the use of a higher cutoff improves the specificity of the test to 96%, it decreases its sensitivity to 83%. CONCLUSIONS: In areas where neuroimaging is absent, NCC diagnosis according to the existing criteria is problematic. Taking into account its limitations for diagnosis of inactive NCC, antigen detection can be of added value for diagnosing NCC in PWE by supporting diagnostic and treatment decisions. Therefore, we recommend a revision of the "Del Brutto diagnostic criteria" for use in resource poor areas and suggest the inclusion of serum antigen detection as a major criterion.

  8. Development of monoclonal antibodies and quantitative ELISAs targeting insulin-degrading enzyme

    Directory of Open Access Journals (Sweden)

    Dickson Dennis W

    2009-10-01

    Full Text Available Abstract Background Insulin-degrading enzyme (IDE is a widely studied zinc-metalloprotease implicated in the pathogenesis of type 2 diabetes mellitus, Alzheimer disease (AD and varicella zoster virus infection. Despite more than six decades of research on IDE, progress has been hampered by the lack of well-characterized reagents targeting this biomedically important protease. To address this important need, we generated and characterized new mouse monoclonal antibodies (mAbs targeting natively folded human and rodent IDE. Results Eight monoclonal hybridoma cell lines were derived in house from mice immunized with full-length, natively folded, recombinant human IDE. The mAbs derived from these lines were shown to detect IDE selectively and sensitively by a wide range of methods. Two mAbs in particular—designated 6A1 and 6H9—proved especially selective for IDE in immunocytochemical and immunohistochemical applications. Using a variety of methods, we show that 6A1 selectively detects both human and rodent IDE, while 6H9 selectively detects human, but not rodent, IDE, with both mAbs showing essentially no cross reactivity with other proteins in these applications. Using these novel anti-IDE mAbs, we also developed sensitive and quantitative sandwich ELISAs capable of quantifying IDE levels present in human brain extracts. Conclusion We succeeded in developing novel mAbs that selectively detect rodent and/or human IDE, which we have shown to be suitable for a wide range of applications, including western blotting, immunoprecipitation, immunocytochemistry, immunohistochemistry, and quantitative sandwich ELISAs. These novel anti-IDE mAbs and the assays derived from them constitute important new tools for addressing many unresolved questions about the basic biology of IDE and its role in multiple highly prevalent human diseases.

  9. Validation of indirect ELISA systems for the serodiagnosis of bovine trypanosomosis in endemic areas of Kenya

    International Nuclear Information System (INIS)

    Ouma, J.O.; Mwangi, J.M.; Mdachi, R.; Njiru, Z.K.; Ndung'u, J.M.

    2000-01-01

    The present study was aimed at validating the performance of four indirect ELISA systems developed for the detection of anti-trypanosomal antibodies in bovine serum. The assay systems employ the use of either native or denatured crude lysate antigens prepared from Trypanosoma congolense (Tc) and Trypanosoma vivax (Tv). Assay systems were designated as TcAGd, TcAGn, TvAGd or TvAGn depending on the trypanosome species from which the antigen was prepared (Tc or Tv) and whether the antigen was denatured (AGd) or native (AGn). The microtitre plates used were precoated with the above antigen preparations at the International Atomic Energy Agency laboratories in Vienna, Austria and shipped to Kenya. Diagnostic sensitivities and specificities were assessed using both known infected and uninfected bovine sera, respectively. All the positive samples were collected from cattle kept in trypanosomosis endemic areas of Galana and Ukunda in Coast province and Mfangano Island in Nyanza province of Kenya. Known negative sera were obtained from animals kept in a non-trypanosomosis endemic area in Muguga, near Nairobi, Kenya. Assay sensitivity ranged from 86% to 97%, while specificity was between 82% and 100% depending on the assay system used. Systems employing denatured antigens had slightly higher, diagnostic sensitivity and specificity. The study has demonstrated that antigen precoated plates are useful in circumventing the problem of antigen instability. However, further studies need to be undertaken using a larger sample size to determine if there are any significant differences between plates pre-coated with native and denatured antigens. The present version of indirect ELISA is a useful epidemiological tool and can be incorporated in mapping out the extent of disease. (author)

  10. Herida precordial por arma blanca

    OpenAIRE

    Marcelo F. Jiménez; Nuria Novoa; José Luis Aranda; Gonzalo Varela

    2005-01-01

    Varón de 42 años con esquizofrenia paranoide. Intento de suicidio con tres autolesiones por arma blanca (Fig. 1). Fue traído al hospital en estado consciente, taquicárdico, taquipneico y con tensión arterial (TA) de 140/90 mmHg. Fue trasladado al quirófano, donde se practicó una toracotomía axilar izquierda sin extraer el arma. Durante la intervención se apreciaron tres heridas incisas, dos no penetrantes, hemotórax de 150 ml, herida pericárdica de 4 cm, sin lesiones cardíacas. La hoja del ar...

  11. Prueba de Elisa indirecta del lisado total de Bartonella bacilliformis para el diagnóstico rápido de la enfermedad de Carrión

    Directory of Open Access Journals (Sweden)

    Elizabeth Anaya

    2008-04-01

    Full Text Available Se elaboró y estandarizó una prueba de ELISA indirecta con el lisado total de Bartonella bacilliformis procedentes de una cepa ATCC y de un aislamiento clínico. Se seleccionaron 86 sueros de pacientes con diagnóstico confirmado de enfermedad de Carrión por frotis y cultivo, 51 sueros negativos de pacientes de zonas no endémicas y 32 sueros de pacientes con diagnóstico serológico confirmado para otras enfermedades bacterianas como brucelosis, leptospirosis, sífilis y Rickettsiosis. Se encontró una sensibilidad de 68,6% (IC95%: 58,2-79,0%, especificidad de 94,1% (86,7-100%, valor predictivo positivo de 95,2% (89,0-100% y valor predictivo negativo de 64,0% (54,3-71,2%, con una reacción cruzada con otras etiologías bacterianas de 78,1% (25/32. Esta no es una prueba idónea para ser usada como herramienta diagnóstica para la Enfermedad de Carrión, se debe continuar los estudios hacia la búsqueda de una prueba rápida con mayor sensibilidad.

  12. An enzyme-linked immunosorbent assay (ELISA) for quantification of mouse surfactant protein D (SP-D)

    DEFF Research Database (Denmark)

    Hansen, Soren; Schmidt, Vivi; Steffensen, Maria Abildgaard

    2008-01-01

    characterized and validated for use in sandwich enzyme-linked immunosorbent assay (ELISA). Based on two of these, we established an ELISA that allows for measurements of mouse SP-D in various body fluids. The final ELISA was optimized and calibrated with a standard of purified recombinant mouse SP-D, which......Surfactant protein D (SP-D) is a pattern recognition molecule of the collectin family of C-type lectins. It is found in the airways and at mucosal surfaces. SP-D is part of the innate immune system where it neutralizes and leads to elimination of microorganisms. It regulates the functions of other...... innate immune cells, such as macrophages and neutrophils. It also modulates the adaptive immune response by interacting with antigen-presenting cells and T cells. Monoclonal anti-mouse-SP-D antibodies were raised from SP-D deficient mice using recombinant SP-D as antigen. Ten monoclonal antibodies were...

  13. Science with the space-based interferometer eLISA. II. Gravitational waves from cosmological phase transitions

    International Nuclear Information System (INIS)

    Caprini, Chiara; Hindmarsh, Mark; Helsinki Univ.; Huber, Stephan

    2016-04-01

    We investigate the potential for the eLISA space-based interferometer to detect the stochastic gravitational wave background produced by strong first-order cosmological phase transitions. We discuss the resulting contributions from bubble collisions, magnetohydrodynamic turbulence, and sound waves to the stochastic background, and estimate the total corresponding signal predicted in gravitational waves. The projected sensitivity of eLISA to cosmological phase transitions is computed in a model-independent way for various detector designs and configurations. By applying these results to several specific models, we demonstrate that eLISA is able to probe many well-motivated scenarios beyond the Standard Model of particle physics predicting strong first-order cosmological phase transitions in the early Universe.

  14. Demonstration of immunogenic keratan sulphate in commercial chondroitin 6-sulphate from shark cartilage. Implications for ELISA assays

    DEFF Research Database (Denmark)

    Møller, H J; Møller-Pedersen, T; Damsgaard, T E

    1995-01-01

    The prototype monoclonal keratan sulphate (KS) antibody 5D4 that is widely used for detection of KS in tissues and biological fluids reacts strongly with commercial low grade shark cartilage chondroitin 6-sulphate. Characterization of the immunogenic material by chondroitinase ABC digestion, ELISA...... inhibition studies, immunoblotting and HPLC analyses confirmed the presence of substantial amounts of KS, probably as a large proteoglycan (> 120 kDa). Commercial and heterogenic glycosaminoglycan preparations therefore must be used with great caution in immunological analyses. On the other hand the shark...... cartilage chondroitin 6-sulphate is an easy accessible source of immunogenic KS that can be used as a reference standard and as coating antigen in KS-ELISAs. The concentration of immunogenic KS in synovial fluid measured with an ELISA based solely on reagents of shark cartilage chondroitin 6-sulphate...

  15. An enzyme-linked immunosorbent assay (ELISA) for quantification of human collectin 11 (CL-11, CL-K1)

    DEFF Research Database (Denmark)

    Selman, L; Henriksen, M L; Brandt, J

    2012-01-01

    -associated serine protease 1 (MASP-1) and/or MASP-3 in circulation. Mutation in the CL-11 gene was recently associated with the developmental syndrome 3MC. In the present study, we established and thoroughly validated a sandwich enzyme-linked immunosorbent assay (ELISA) based on two different monoclonal antibodies....... The assay is highly sensitive, specific and shows excellent quantitative characteristics such as reproducibility, dilution linearity and recovery (97.7-104%). The working range is 0.15-34 ng/ml. The CL-11 concentration in two CL-11-deficient individuals affected by the 3MC syndrome was determined...... and thawing to a certain extent did not influence the ELISA. This ELISA offers a convenient and reliable method for studying CL-11 levels in relation to a variety of human diseases and syndromes....

  16. Testes de ELISA e vírus-neutralização na detecção de anticorpos contra o vírus da diarréia viral bovina no leite

    Directory of Open Access Journals (Sweden)

    Diego A.F. Sturza

    2011-11-01

    Full Text Available O sucesso na estratégia de controle e erradicação do vírus da diarréia viral bovina (BVDV, passa necessariamente pela identificação e eliminação dos animais persistentemente infectados (PI. Como esses animais excretam continuamente o vírus em suas secreções e excreções, a prevalência de anticorpos no rebanho, frequentemente é alta e com altos títulos. Devido a essas características, amostras de tanques coletivos de leite, foram submetidas a duas técnicas sorológicas, a fim de estabelecer a mais adequada na realização de triagem de rebanhos. Para isso, 767 amostras coletivas de leite foram submetidas à análise por um kit ELISA indireto (teste referência e pela técnica de vírus-neutralização (VNT adaptada (teste proposto. Devido aos efeitos tóxicos do leite sobre o cultivo celular, a adaptação consistiu no aumento do volume final na etapa de incubação celular. Foram positivas, 177 e 139 amostras no ELISA e na VNT, respectivamente. Com isso, a VNT adaptada apresentou uma sensibilidade de 76,8% e uma especificidade de 99,5%. O índice Kappa (k foi de 0,82, demonstrando uma ótima concordância entre as duas técnicas. A análise do coeficiente de correlação entre os valores de absorbância no ELISA (OD e os títulos de anticorpos na VNT nas amostras positivas, demonstrou uma positividade moderada (r = 0,57 com p < 0,05. No entanto, várias amostras com títulos altos na VNT apresentaram ODs moderadas ou baixas. Por outro lado, algumas amostras com títulos neutralizantes baixos apresentaram ODs altas. Como a presença de animais PI é sugerida por títulos neutralizantes ≥ 80, conclui-se que a técnica de VNT adaptada é mais adequada para a realização de triagem em amostras coletivas de leite quando objetiva-se detectar rebanhos com altos títulos de anticorpos.

  17. Broad spectrum reactivity versus subtype specificity-trade-offs in serodiagnosis of influenza A virus infections by competitive ELISA.

    Science.gov (United States)

    Postel, A; Ziller, M; Rudolf, M; Letzel, T; Ehricht, Ralf; Pourquier, P; Dauber, M; Grund, C; Beer, Martin; Harder, T C

    2011-04-01

    Avian influenza viruses (AIVs) of the H5 and H7 subtypes can cause substantial economic losses in the poultry industry and are a potential threat to public health. Serosurveillance of poultry populations is an important monitoring tool and can also be used for control of vaccination campaigns. The purpose of this study was to develop broadly reactive, yet subtype-specific competitive ELISAs (cELISAs) for the specific detection of antibodies to the notifiable AIV subtypes H5 and H7 as an alternative to the gold standard haemagglutination inhibition assay (HI). Broadly reacting monoclonal competitor antibodies (mAbs) and genetically engineered subtype H5 or H7 haemagglutinin antigen, expressed and in vivo biotinylated in insect cells, were used to develop the cELISAs. Sera from galliform species and water fowl (n=793) were used to evaluate the performance characteristics of the cELISAs. For the H5 specific cELISA, 98.1% test sensitivity and 91.5% test specificity (97.7% and 90.2% for galliforms; 98.9% and 92.6% for waterfowl), and for the H7 cELISA 97.3% sensitivity and 91.8% specificity (95.3% and 98.9% for galliforms; 100% and 82.7% for waterfowl) were reached when compared to HI. The use of competitor mAbs with broad spectrum reactivity within an AIV haemagglutinin subtype allowed for homogenous detection with high sensitivity of subtype-specific antibodies induced by antigenically widely distinct isolates including antigenic drift variants. However, a trade-off regarding sensitivity versus nonspecific detection of interfering antibodies induced by phylo- and antigenically closely related subtypes, e.g., H5 versus H2 and H7 versus H15, must be considered. The observed intersubtype antibody cross-reactivity remains a disturbance variable in AIV subtype-specific serodiagnosis which negatively affects specificity. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Image-based ELISA on an activated polypropylene microtest plate--a spectrophotometer-free low cost assay technique.

    Science.gov (United States)

    Parween, Shahila; Nahar, Pradip

    2013-10-15

    In this communication, we report ELISA technique on an activated polypropylene microtest plate (APPµTP) as an illustrative example of a low cost diagnostic assay. Activated test zone in APPµTP binds a capture biomolecule through covalent linkage thereby, eliminating non-specific binding often prevalent in absorption based techniques. Efficacy of APPµTP is demonstrated by detecting human immunoglobulin G (IgG), human immunoglobulin E (IgE) and Aspergillus fumigatus antibody in patient's sera. Detection is done by taking the image of the assay solution by a desktop scanner and analyzing the color of the image. Human IgE quantification by color saturation in the image-based assay shows excellent correlation with absorbance-based assay (Pearson correlation coefficient, r=0.992). Significance of the relationship is seen from its p value which is 4.087e-11. Performance of APPµTP is also checked with respect to microtiter plate and paper-based ELISA. APPµTP can quantify an analyte as precisely as in microtiter plate with insignificant non-specific binding, a necessary prerequisite for ELISA assay. In contrast, paper-ELISA shows high non-specific binding in control sera (false positive). Finally, we have carried out ELISA steps on APPµTP by ultrasound waves on a sonicator bath and the results show that even in 8 min, it can convincingly differentiate a test sample from a control sample. In short, spectrophotometer-free image-based miniaturized ELISA on APPµTP is precise, reliable, rapid, and sensitive and could be a good substitute for conventional immunoassay procedures widely used in clinical and research laboratories. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Diagnostic accuracy study of a factor VIII ELISA for detection of factor VIII antibodies in congenital and acquired haemophilia A.

    Science.gov (United States)

    Batty, Paul; Moore, Gary W; Platton, Sean; Maloney, James C; Palmer, Ben; Bowles, Louise; Pasi, K John; Rangarajan, Savita; Hart, Daniel P

    2015-10-01

    Antibody formation to factor VIII (FVIII) remains the greatest clinical and diagnostic challenge to the haemophilia-treating physician. Current guidance for testing for inhibitory FVIII antibodies (inhibitors) recommends the functional Nijmegen-Bethesda assay (NBA). A FVIII ELISA offers a complementary, immunological approach for FVIII antibody testing. It was the aim of this study to retrospectively evaluate the performance of a FVIII ELISA (index) for detection of FVIII antibodies, compared with the NBA (reference). All samples sent for routine FVIII antibody testing at two haemophilia Comprehensive Care Centres, were tested in parallel using the NBA and a solid-phase, indirect FVIII ELISA kit (Immucor). A total of 497 samples from 239 patients (severe haemophilia A=140, non-severe haemophilia A=85, acquired haemophilia A=14) were available for analysis. Sixty-three samples tested positive by the NBA (prevalence 12.7%, 95% confidence interval [CI], 9.9-15.9 %), with a median inhibitor titre of 1.2 BU/ml (range 0.7-978.0). The FVIII ELISA demonstrated a specificity of 94.0% (95%CI, 91.3-96.0), sensitivity of 77.8% (95%CI, 65.5-87.3), negative predictive value of 96.7% (95%CI, 94.5-98.2), positive predictive value 65.3% (95%CI, 53.5-76.0), negative likelihood ratio 0.2 (95%CI, 0.1-0.4), positive likelihood ratio 13.0 (95%CI, 8.7-19.3) and a diagnostic odds ratio of 54.9 (95%CI, 27.0-112.0). Strong positive correlation (r=0.77, pNBA (log adjusted) and FVIII ELISA optical density. In conclusion, FVIII ELISA offers a simple, specific, surveillance method enabling batch testing of non-urgent samples for the presence of FVIII antibodies.

  20. Detecting diclofenac in livestock carcasses in India with an ELISA: A tool to prevent widespread vulture poisoning

    International Nuclear Information System (INIS)

    Saini, Mohini; Taggart, Mark A.; Knopp, Dietmar; Upreti, Suchitra; Swarup, Devendra; Das, Asit; Gupta, Praveen K.; Niessner, Reinhard; Prakash, Vibhu; Mateo, Rafael; Cuthbert, Richard J.

    2012-01-01

    Diclofenac, a non-steroidal anti-inflammatory drug (NSAID), has caused catastrophic vulture declines across the Indian sub-continent. Here, an indirect ELISA is used to detect and quantify diclofenac in 1251 liver samples from livestock carcasses collected across India between August 2007 and June 2008, one to two years after a ban on diclofenac manufacture and distribution for veterinary use was implemented. The ELISAs applicability was authenticated with independent data obtained using LC–ESI/MS. Of 1251 samples, 1150 (91.9%) were negative for diclofenac using both methods, and 60 (4.8%) were positive at 10–4348 and 10–4441 μg kg −1 when analysed by ELISA and LC–ESI/MS, respectively. The residue level relationship in the 60 positive samples was highly significant (p 2 = 0.644). Data suggest that this immunological assay could be used not only for cost effective sample screening, but also for residue level semi-quantification. - Highlights: ► An ELISA is validated for use in diclofenac monitoring. ► We compare ELISA and LC–ESI/MS data for 1251 samples. ► Results indicate the ELISA can be reliably used for screening and semi-quantification. ► In 2007–2008, in India, around 1 in 20 ungulate carcasses contained detectable diclofenac. - The prevalence of diclofenac in carcasses available to vultures in India has declined from around 1:10 to 1:20 since restrictions on veterinary use were first put in place in 2006.

  1. Assessment of the relative sensitivity of milk ELISA for detection of Mycobacterium avium ssp. paratuberculosis infectious dairy cows.

    Science.gov (United States)

    Laurin, Emilie L; Sanchez, Javier; Chaffer, Marcelo; McKenna, Shawn L B; Keefe, Greg P

    2017-01-01

    Milk ELISA are commonly used for detection of Mycobacterium avium ssp. paratuberculosis (MAP) antibodies in dairy cows, due to low cost and quick processing for large numbers of samples. However, low sensitivity and variations from host and environmental factors can impede detection of MAP antibodies at early disease stages. The objectives of our study were to assess the sensitivity of milk ELISA in comparison with fecal tests and to evaluate how detectable antibody concentrations in milk vary with changes in fecal shedding of MAP, cow age, cow parity, days in milk, and time of year. To compare the sensitivity of a commercial milk ELISA with solid and broth fecal culture and with fecal real-time PCR, a longitudinal study was performed for the identification of MAP-infectious animals as determined by prior fecal testing for MAP shedding. In addition, associations between variation in milk MAP ELISA score and changes in fecal MAP shedding, host age, days in milk, and season were evaluated. Monthly milk and fecal samples were collected over 1 yr from 46 cows that were previously shedding MAP in their feces. Sensitivity of milk ELISA was 29.9% (95% CI: 24.8 to 35.1%), compared with 46.7% (40.7 to 52.7%) for fecal solid culture, 55.0% (49.3 to 60.7%) for fecal broth culture, and 78.4% (73.3 to 83.1%) for fecal direct real-time PCR. The effect of stage of lactation could not be separated from the effect of season, with increased milk ELISA scores at greater days in milk in winter. However, unpredictable monthly variations in results were observed among the 3 assays for individual cow testing, which highlights the importance of identifying patterns in pathogen and antibody detection over time in MAP-positive herds. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  2. Frecuencia de infección por VIH en pacientes con episodio agudo de herpes zoster

    Directory of Open Access Journals (Sweden)

    Susana Lazarte Heraud

    2005-01-01

    Full Text Available Objetivo: Evaluar la frecuencia de infección por VIH en pacientes que consultan por episodio agudo de herpes zoster. Material y Métodos: Se incluyeron a todos los pacientes entre 18 y 49 años, atendidos entre setiembre del 2001 y enero del 2003 en el Departamento de Enfermedades Infecciosas, Tropicales y Dermatológicas del Hospital Nacional Cayetano Heredia, por un cuadro agudo de herpes zoster, diagnosticado clínicamente. Los criterios de inclusión fueron: status VIH desconocido tanto del paciente como de su pareja; que no presentaran alguna complicación neurológica o presentación atípica de zoster y que no tuvieran signos ni síntomas compatibles con infección por VIH (muguet oral, diarrea crónica, síndrome de desgaste, etc.. Previa firma de consentimiento informado, se tomó muestra de sangre para prueba de ELISA para VIH1. A todos los pacientes con resultado positivo se les realizó western blot. Resultados: Veintiún pacientes cumplieron los criterios del estudio, 14 varones y 7 mujeres. Cinco pacientes (23,8% fueron VIH positivos. De éstos, 4 fueron varones (4/14 y 1 mujer (1/7. No se encontró diferencias significativas en cuanto a la conducta sexual de riesgo. Conclusiones: Se encuentra un porcentaje elevado de infección por VIH en adultos jóvenes que consultan en un hospital general por un cuadro agudo de herpes zoster, sin ningún otro signo ni síntoma de inmunosupresión, independientemente de conductas sexuales de riesgo. Nuestro hallazgo justifica un despistaje de VIH en adultos jóvenes con herpes zoster.

  3. Colony to colorimetry in 6 h: ELISA detection of a surface-expressed Pseudomonas aeruginosa virulence factor using immobilized bacteria.

    Science.gov (United States)

    Adawi, Azmi; Neville, Lewis F

    2012-09-01

    A rapid ELISA employing intact Pseudomonas aeruginosa (PA) is described that allows discrimination between strains harboring flagellin type a or b. All 52 PA strains known to harbor flagellin type b were positive in this ELISA when screened with a fully human monoclonal antibody (LST-007) targeting flagellin type b. Completion of this assay in only 6 h, from picking a single bacterial colony to a colorimetric product, could easily be adapted to a clinical laboratory setting and permit the appropriate choice of therapeutic monoclonal antibody versus its homologous flagellin target in PA-infected patients. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Serological survey of African animal trypanosomosis in Ghana: The role of the antigen ELISA as a diagnostic tool

    Energy Technology Data Exchange (ETDEWEB)

    Doku, C K; Seidu, I B.M. [Central Veterinary Lab., Pong-Tamale (Ghana). Tsetse and Trypanosmosis Unit

    1997-02-01

    Preliminary results are presented of the analysis of 3000 serum samples collected from Zebu cattle in the Nabogu valley. Of the 3000 serum samples collected so far, 182 have been tested using the buffy coat technique (BCT) and the antigen ELISA test. A total of 56 samples have been found positive by both techniques. Using the parasitological technique (=BCT) 44 samples were diagnosed to be positive, while the Ag-ELISA detected 19 positive samples. The majority (75%) of cases detected positive by either technique was due to a single infection by Trypanosoma brucei. (author). 4 refs, 1 fig., 3 tabs.

  5. Serological survey of African animal trypanosomosis in Ghana: The role of the antigen ELISA as a diagnostic tool

    International Nuclear Information System (INIS)

    Doku, C.K.; Seidu, I.B.M.

    1997-01-01

    Preliminary results are presented of the analysis of 3000 serum samples collected from Zebu cattle in the Nabogu valley. Of the 3000 serum samples collected so far, 182 have been tested using the buffy coat technique (BCT) and the antigen ELISA test. A total of 56 samples have been found positive by both techniques. Using the parasitological technique (=BCT) 44 samples were diagnosed to be positive, while the Ag-ELISA detected 19 positive samples. The majority (75%) of cases detected positive by either technique was due to a single infection by Trypanosoma brucei. (author). 4 refs, 1 fig., 3 tabs

  6. Introduction and use of ELISA based technologies for the diagnosis and monitoring of foot-and-mouth disease in Malaysia

    International Nuclear Information System (INIS)

    Karuppanan, P.; Naheed, M.

    2000-01-01

    Continued outbreaks of foot-and-mouth disease (FMD) in northern Malaysia drove the decision to establish a diagnostic surveillance capability at the regional laboratory in Kota Bharu. Based on using ELISA based diagnostic systems the laboratory was equipped for the detection of both the conservative virus and a serological response in animals. Considerable detail was given on the subsequent testing that was carried out clearly demonstrating the value both of the ELISA technology but also of what can be achieved at reasonable costs for conducting routine surveillance of FMD. (author)

  7. Micro-enzyme-linked immunosorbent assay (ELISA) and radioimmunosorbent technique (RIST) for the detection of immunity to clinical tetanus

    Energy Technology Data Exchange (ETDEWEB)

    Layton, G T [Royal Infirmary, Manchester (UK)

    1980-10-01

    Enzyme-linked immunosorbent assay (ELISA), and radioimmunosorbent assay (RIST) techniques for the detection of tetanus toxin antibodies are described. Both methods proved to be highly sensitive, and allowed the measurement of 5 x 10/sup -3/ units/ml tetanus antitoxin in human serum or plasma, sensitivity and reproducibility comparing well with other techniques previously described, and being superior to haemagglutination and latex agglutination tests. Results of the two methods correlated well, and reflected the immunization histories obtained. Micro ELISA and micro RIST would seem to be suitable for the detection of immunity, or non-immunity to clinical tetanus.

  8. Use of avidin-biotin-peroxidase complex for measurement of UV lesions in human DNA by microELISA

    Energy Technology Data Exchange (ETDEWEB)

    Leipold, B [Technischen Universitaet Muenchen (Germany, F.R.). Dermatologische Klinik; Remy, W [Max-Planck-Institut fuer Biochemie, Muenchen (Germany, F.R.)

    1984-02-10

    The avidin/biotin system was introduced into the standard enzyme-linked immunosorbent assay (ELISA) to increase its sensitivity for detecting UV lesions in human DNA. Goat anti-rabbit IgG-peroxidase used in the standard ELISA as second antibody was replaced by biotinylated goat anti-rabbit IgG plus the avidin-biotin-peroxidase complex (ABC) reagent. Sensitivity of detection of plate-fixed UV-DNA-antibody complexes was increased about 8-fold and photolesions in human DNA samples irradiated with as low a dose as 1 J/m/sup 2/ UVC or a suberythermal dose of UVB light could be detected.

  9. A micro-enzyme-linked immunosorbent assay (ELISA) and radioimmunosorbent technique (RIST) for the detection of immunity to clinical tetanus

    International Nuclear Information System (INIS)

    Layton, G.T.

    1980-01-01

    Enzyme-linked immunosorbent assay (ELISA), and radioimmunosorbent assay (RIST) techniques for the detection of tetanus toxin antibodies are described. Both methods proved to be highly sensitive, and allowed the measurement of 5 x 10 -3 units/ml tetanus antitoxin in human serum or plasma, sensitivity and reproducibility comparing well with other techniques previously described, and being superior to haemagglutination and latex agglutination tests. Results of the two methods correlated well, and reflected the immunization histories obtained. Micro ELISA and micro RIST would seem to be suitable for the detection of immunity, or non-immunity to clinical tetanus. (author)

  10. Miotoxicidade por organofosforados Organophosphate myotoxicity

    Directory of Open Access Journals (Sweden)

    Maria J. Cavaliere

    1996-06-01

    Full Text Available Os organofosforados são um grupo de compostos químicos amplamente utilizados em agropecuária como inseticidas, ocasionando intoxicações acidentais em animais e humanos, e mesmo sendo utilizados em tentativas de suicídio. A toxicidade desses produtos decorre sobretudo de insuficiência cárdio-respiratória por compromentimento do sistema nervoso autônomo. Sabe-se que alguns destes compostos induzem em animais de experimentação e em humanos, uma miopatia caracterizada por degeneração de células musculares, comprometendo sobretudo a musculatura respiratória. Baseado no fato de que este comprometimento contribui para a piora da função respiratória, propõe-se um protocolo de avaliação rotineira de miotoxicidade por compostos organofosforados, através de uma bateria mínima e suficiente de colorações e reações histoquímicas para quantificação da necrose muscular. Utilizaram-se como modelo experimental, grupos de ratos albinos (Wistar intoxicados com o organofosforado paraoxon, com e sem antídotos (atropina ou pralidoxima. Verificou-se nos grupos tratados com paraoxon e paraoxon mais atropina, necrose de fibras musculares no diafragma, que atingia em determinadas áreas até 15% das fibras. No grupo tratado com paraoxon mais pralidoxima, a necrose foi mínima, evidenciando o papel mioprotetor deste último antídoto.Organophosphates comprise a group of chemical compounds extensively used in farming as insecticides, which cause accidental poisoning in animals and men and are also used in suicide attempts. The toxicity of these compounds is due especially to the cardiac and respiratory impairment in consequence of autonomic nervous system disorders. However, it is known that some of these products induce a myopathy in experimental animals and humans. This myopathy is characterized by muscle cell degeneration, involving above all the respiratory muscles. Based on the fact that this involvement certainly enhances the

  11. Development and optimization of an ESAT6-ELISA-based detection system of Mycobacterium tuberculosis complex, suitable for bovine TB eradication

    Directory of Open Access Journals (Sweden)

    Rouhollah Keshavarz

    2015-01-01

    Conclusion: Performing the ELISA test based on ESAT-6 antigen shows that this test can be a suitable way for screening beside the tuberculin test for accurate detection. It is noticed that the specificity of the ELISA test was determined more than the tuberculin test, especially since the culture and PCR are gold standards. Therefore, incorrect sampling can change the specificity of the tuberculin test. The results of this kit can encourage designing of an ELISA kit for the detection of human TB.

  12. Prevalence of Peste Des Petits Ruminants Virus (PPRV in Mardan, Hangu and Kohat District of Pakistan; Comparative Analysis of PPRV Suspected serum samples using Competitive ELISA (cELISA and Agar Gel Immunodiffusion (AGID

    Directory of Open Access Journals (Sweden)

    Misbah Aslam

    2009-06-01

    Full Text Available Peste des petits Ruminants (PPR is an acute, febrile, highly contagious and economically important viral disease of small ruminants. However PPR is more prevalent in sheep and goat. Competitive ELISA, Virus neutrilization test, and RT-PCR are the available techniques for diagnosis of PPR which give rapid detection where as Agar gel immunodiffusion and Counter immunoelectrophoresis were previously used for PPR detection. In this study two serological techniques were compared for PPR diagnosis. The main aim of this study was to evaluate the comparative sensitivity of both techniques for PPR detection. For this purpose one hundred and sixty PPR suspected serum samples collected from goats and sheep flocks (unvaccinated from three Districts of NWFP including Mardan, Hangu and Kohat were analyzed in National Veterinary Laboratories, Islamabad. Out of these 160 samples, fifty (50 were found positive for PPR antibodies with cELISA (Prevalence = 31.25%. The cELISA positive serum samples however gave negative results when tested with AGID although the control well was always positive. Thus it was concluded that cELISA technique is more sensitive and specific than AGID for PPR antibody detection. [Vet. World 2009; 2(3.000: 89-92

  13. Agricultural production - Phase 2. Indonesia. Validation of the ELISA technique for the diagnosis of bovine brucellosis and in the use of computer programs for recording and analysing ELISA data

    International Nuclear Information System (INIS)

    Eisler, M.C.

    1992-01-01

    In this mission three principal regional diagnostic laboratories of the Directorate General of Livestock Services in Indonesia were visited and advice was provided on the implementation of ELISA technology for the ser-diagnosis of important livestock diseases, especially bovine brucellosis

  14. Evaluation of a Commercial IgE ELISA in Comparison with IgA and IgM ELISAs, IgG Avidity Assay and Complement Fixation for the Diagnosis of Acute Toxoplasmosis

    Czech Academy of Sciences Publication Activity Database

    Kodym, P.; Machala, L.; Roháčová, H.; Širocká, B.; Malý, Marek

    2007-01-01

    Roč. 13, č. 1 (2007), s. 40-47 ISSN 1198-743X Source of funding: V - iné verejné zdroje Keywords : acute infection * diagnosis * IgE ELISA * lymphadenopathy * serology * toxoplasmosis Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 2.980, year: 2007

  15. ELISA-PLA: A novel hybrid platform for the rapid, highly sensitive and specific quantification of proteins and post-translational modifications.

    Science.gov (United States)

    Tong, Qing-He; Tao, Tao; Xie, Li-Qi; Lu, Hao-Jie

    2016-06-15

    Detection of low-abundance proteins and their post-translational modifications (PTMs) remains a great challenge. A conventional enzyme-linked immunosorbent assay (ELISA) is not sensitive enough to detect low-abundance PTMs and suffers from nonspecific detection. Herein, a rapid, highly sensitive and specific platform integrating ELISA with a proximity ligation assay (PLA), termed ELISA-PLA, was developed. Using ELISA-PLA, the specificity was improved by the simultaneous and proximate recognition of targets through multiple probes, and the sensitivity was significantly improved by rolling circle amplification (RCA). For GFP, the limit of detection (LOD) was decreased by two orders of magnitude compared to that of ELISA. Using site-specific phospho-antibody and pan-specific phospho-antibody, ELISA-PLA was successfully applied to quantify the phosphorylation dynamics of ERK1/2 and the overall tyrosine phosphorylation level of ERK1/2, respectively. ELISA-PLA was also used to quantify the O-GlcNAcylation of AKT, c-Fos, CREB and STAT3, which is faster and more sensitive than the conventional immunoprecipitation and western blotting (IP-WB) method. As a result, the sample consumption of ELISA-PLA was reduced 40-fold compared to IP-WB. Therefore, ELISA-PLA could be a promising platform for the rapid, sensitive and specific detection of proteins and PTMs. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Herida precordial por arma blanca

    Directory of Open Access Journals (Sweden)

    Marcelo F. Jiménez

    2005-04-01

    Full Text Available Varón de 42 años con esquizofrenia paranoide. Intento de suicidio con tres autolesiones por arma blanca (Fig. 1. Fue traído al hospital en estado consciente, taquicárdico, taquipneico y con tensión arterial (TA de 140/90 mmHg. Fue trasladado al quirófano, donde se practicó una toracotomía axilar izquierda sin extraer el arma. Durante la intervención se apreciaron tres heridas incisas, dos no penetrantes, hemotórax de 150 ml, herida pericárdica de 4 cm, sin lesiones cardíacas. La hoja del arma blanca penetraba a través del diafragma produciendo una herida incisa en el lóbulo hepático izquierdo (Fig. 2. Se extrajo el arma y se suturó la laceración hepática. El paciente fue trasladado el cuarto día a la Unidad de Psiquiatría.

  17. por láser

    Directory of Open Access Journals (Sweden)

    Mayra Garcimuño

    2013-01-01

    Full Text Available En el presente trabajo, la técnica Espectroscopia de plasmas producidos por láser (Laser-induced breakdown spectroscopy –LIBS– se aplicó a la determinación cuan- titativa de Na en agua natural dulce, de interés en agricultura para el estudio de la alcalinidad de aguas de regadío. Para efectuar el análisis, se prepararon soluciones con concentraciones conocidas del analito, se mezclaron con óxido de calcio y se compactaron en pastillas sólidas. Los plasmas se produjeron en aire a presión atmos- férica utilizando un láser pulsado Nd:YAG. Se construyó una curva de calibración y se calculó el límite de detección. Se analizaron muestras de agua natural y los resultados se compararon con los obtenidos mediante espectroscopia de absorción atómica. Se demostró la factibilidad del método para la determinación de Na en agua natural dulce.

  18. Osteomalacia inducida por tumor: hemangiopericitoma rinosinusal

    Directory of Open Access Journals (Sweden)

    Enriqueta M. Serafini

    2013-02-01

    Full Text Available La osteomalacia inducida por tumor es una rara enfermedad del metabolismo óseo caracterizada por el aumento en la excreción de fosfato a nivel renal seguido de hipofosfatemia. Es causada por agentes fosfatúricos producidos por determinados tumores. La resección total del tumor resulta en la completa reversión de las anormalidades bioquímicas, la desaparición de las manifestaciones clínicas y los hallazgos en los estudios por imágenes. Presentamos el caso de un varón de 61 años con cuadro clínico y laboratorio compatibles con osteomalacia oncogénica inducida por tumor mesenquimático de localización rinosinusal. En nuestro caso el diagnóstico histológico correspondió a una neoplasia de tipo vascular: hemangiopericitoma.

  19. Evaluación de una prueba de ELISA con antígeno metabólico de Fasciola hepatica para el diagnóstico de fasciolosis humana en Cajamarca, Perú Evaluation of an ELISA test with Fasciola hepatica metabolic antigen for diagnosis of human fascioliasis in Cajamarca, Peru

    Directory of Open Access Journals (Sweden)

    Hernán Cornejo

    2010-12-01

    Full Text Available Se obtuvo el antígeno metabólico (antígeno excreción - secreción de Fasciola hepatica de ovinos infectados de Cajamarca, con una concentración proteica de 1 005 μg/μL, compuesta principalmente por proteνnas de peso molecular entre 1,2 y 170 KDa. Se detectaron bandas de 170; 150; 31; 24; 18-14 y 10 kDa. Con este antνgeno se desarrollσ una prueba de ELISA y se determinσ su punto de corte en 0,140. Se evaluσ 33 sueros de pacientes con fasciolosis confirmada por visualización de huevos en heces, 177 sueros de pacientes sin fasciolosis provenientes de áreas endémicas de Cajamarca y 88 sueros de pacientes con otras infecciones parasitarias y bacterianas. Se encontró una sensibilidad de 97,0%, especificidad de 96,6%, valor predictivo positivo de 78,1% y valor predictivo negativo de 99,6%. Se encontró reacción cruzada en 9/88 sueros evaluados. Se recomienda la implementación y uso de esta prueba para el diagnóstico de fasciolosis.Metabolic (excretion/secretion antigen was obtained from sheep infected with Fasciola hepatica, with a 1005 μg/μL of protein concentration, composed principally by proteins of molecular weight between 1.2 and 170 KDa. Bands of 170, 150, 31, 24, 18-14 and 10 kDa were detected. With this antigen an ELISA test was developed and the cut off was determined in 0.140. We evaluated 33 serums of patient with fascioliasis confirmed by visualization of eggs in feces, 177 serums of persons without fascioliasis from endemic rural areas of Cajamarca and 88 serums of patients with others parasitic and bacterial infections. We found a 97.0% of sensitivity, 96.6 specificity, 78.1% predictive positive value, 99.6 % predictive negative value. In 9/88 serums was found cross reactions. We recommended the implementation and use of this test for the fascioliasis diagnosis.

  20. Non-competitive ELISA with broad specificity for microcystins and nodularins

    Directory of Open Access Journals (Sweden)

    Sultana Akter

    2017-05-01

    Full Text Available Simple and cost-effective methods with sufficient sensitivities for preliminary screening of cyanobacterial toxins are in high demand for assessing water quality and safety. We have recently developed a highly sensitive and rapid time-resolved fluorometry based non-competitive immunoassay for detection of microcystins and nodularins. The assay is based on a synthetic broad-specific anti-immunocomplex antibody SA51D1 capable of recognizing the immunocomplex formed by a generic anti-Adda monoclonal antibody (mAb bound to either microcystins or nodularins. Using the same antibody pair, here we describe a very simple and cost-efficient non-competitive ELISA test for microcystins and nodularins based on conventional alkaline phosphatase (AP activity measurement. The recombinant SA51D1 single-chain fragment of antibody variable domain (scFv was produced as a fusion with bacterial alkaline phosphatase in Escherichia coli. After one step affinity purification through His-tag, the scFv-AP fusion protein could directly be used in the assay. For the assay, toxin standard/sample, biotinylated anti-Adda mAb and the scFv-AP were incubated together for one hour on streptavidin-coated microtiter wells, washed and AP activity was then measured by incubating (1 h at 37 ˚C with chromogenic substrate para-nitrophenylphosphate (pNPP. The assay was capable of detecting all the eleven tested toxin variants (microcystin-LR, -dmLR, -RR, -dmRR, -YR, LA -LY, -LF -LW, -WR, and nodularin-R below WHO guide line value of 1 µg L-1. The detection limit (based on blank+3SD response for microcystin-LR was ~0.2 µg L-1. The assay was verified using spiked (0.25 - 4 µg L-1 of microcystin-LR tap, river and lake water samples with recoveries from 64 to 101%. The assay showed good correlation (r2>0.9 with four reference methods for its performance in detecting extracted intracellular microcystin/nodularin from 17 natural surface water samples. The described easy-to-perform assay

  1. detection of aflatoxin M1 contamination in milk for Syrian market using ELISA

    International Nuclear Information System (INIS)

    Ghanem, I.; Orfi, M.

    2008-01-01

    Aflatoxin M1 (AFM1) is the hydroxylated metabolite of a biotransformation process of Aflatoxin B1 (AFB1) which is produced in food and feed by the fungi Aspergillus flavus and A. paraciticus. AFM1 has been shown to be excreted in milk following exposure to AFB1 contaminated feed. Since milk is consumed in large quantities by human populations, particularly among infants and young children the occurrence of AFM1 in this product is constitutes and health hazard since it is carcinogenic and has been listed as Class 2B carcinogen. The occurrence of AFM1 in milk samples from the Syrian market was investigated by the competitive ELISA technique. A total of 126 samples consisting of fresh cow milk (74), locally processed pasteurized cow milk (10), sheep milk (23), goat milk (11) and powdered milk and infant formula (8) showed that the incidence of contamination, i.e. above the detection limit of the ELISA assay, was 80%. 18% of the tested samples contained higher than the acceptable level of AFM1 adopted in Syria, which is 200 ng/kg; whereas, 17% and 54% of all tested samples contained AFM1 higher than the acceptable level in the US, (500 ng/kg) and in the European Union (50 ng/kg), respectively. The range of contamination with AFM1 was higher in cow milk samples than in sheep milk and goat milk samples. 30% of the analyzed cow fresh milk samples contained levels of AFM1 exceeding that of the European Communities (Codex Alimentarius) recommended limits (50 ng/l); whereas, 13% of the analyzed sheep milk samples (23) exceeded the latter limit, and only 9% of the analyzed goat milk samples exceeded same limit. Pasteurized milk, which is collected from various locations, showed particularly high level of contamination, with 80% and 50% of tested samples showing levels of contamination higher than the European and US acceptable levels, respectively. Powdered milk and infant formula, which are imported and only dispensed locally, were free of contamination. The above result

  2. Effect of the presence of two commercial adsorbents in animal feed on Aflatoxin B1 determination by ELISA kit test

    Directory of Open Access Journals (Sweden)

    Francesco Masoero

    2010-01-01

    Full Text Available A rapid AFB1 detection method by ELISA kit test was used on feedstuff samples, and compared to an HPLC method, to verify if the presence of clay-adsorbent (SA could cause erroneous quantification of the toxin. Samples were obtained using two AFB1-contaminated feedstuffs (7.92 and 17.58 µg/kg for low and high contaminated feeds; LC and HC respectively, added either one of two commercial SAs (Atox® and Myco AD and three different inclusion doses (0, 10 and 20 g/kg, respectively for CTR, 1% and 2% doses. The HPLC and ELISA data were compared in CTR samples with a paired t-test. The AFB1 recoveries, performed with ELISA, were analysed as a completely randomized design using a 2×2×3 factorial arrangement. The ELISA method tended to underestimate the AFB1 concentrations with respect to the HPLC method, both in HC (P=0.050 and in LC (P<0.001 feedstuffs. A more drastic reduction (P<0.001 was observed when SAs were included in the two feedstuffs. In particular, Atox® determined an AFB1 recovery of 15,5% in HC and 7,6% in LC (1% dose and of 11,1% in HC and 8,4% in LC (2% dose. Less severe penalisation were observed when Myco AD was added to feeds.

  3. Comparison of in-house IgM and IgG ELISAs for the serodiagnosis of melioidosis in Malaysia.

    Science.gov (United States)

    Hii, Shirley Yi Fen; Ali, Noor Azila; Ahmad, Norazah; Amran, Fairuz

    2017-11-01

    Melioidosis is an endemic infectious disease in Southeast Asia and northern Australia, caused by Burkholderia pseudomallei. However, the incidence rate in Malaysia is not well documented. The high mortality rate and broad range of clinical presentations require rapid and accurate diagnosis for appropriate treatment. This study compared the efficacy of in-house IgM and IgG ELISA methods using a local B. pseudomallei strain. The diagnostic accuracy of the in-house IgG ELISA was better than that of the IgM ELISA: sensitivity (IgG: 84.71 %, IgM: 76.14 %) and specificity (IgG: 93.64 %, IgM: 90.17 %); positive predictive value (IgG: 86.75 %, IgM: 79.76 %) and negative predictive value (IgG: 92.57 %, IgM: 89.66 %); likelihood ratio (LR) [IgG: 13.32, IgM: 7.75 (LR+); IgG: 0.16, IgM: 0.26 (LR-)], and was supported by the observation of the absorbance value in comparisons between culture and serology sampling. In-house IgG ELISA was shown to be useful as an early diagnostic tool for melioidosis.

  4. Development of a sensitive ELISA for the quantification of human tumour necrosis factor-alpha using 4 polyclonal antibodies.

    NARCIS (Netherlands)

    Grebenchtchikov, N.J.; Ven-Jongekrijg, J. van der; Pesman, G.J.; Geurts-Moespot, A.; Meer, J.W.M. van der; Sweep, C.G.J.

    2005-01-01

    Despite the availability of many assays to measure concentrations of tumour necrosis factor alpha (TNF-alpha) in body fluids, these assays often lack specificity or sensitivity and are often of questionable reliability, resulting in inconsistent results. Therefore, we have developed an ELISA that is

  5. Full automation and validation of a flexible ELISA platform for host cell protein and protein A impurity detection in biopharmaceuticals.

    Science.gov (United States)

    Rey, Guillaume; Wendeler, Markus W

    2012-11-01

    Monitoring host cell protein (HCP) and protein A impurities is important to ensure successful development of recombinant antibody drugs. Here, we report the full automation and validation of an ELISA platform on a robotic system that allows the detection of Chinese hamster ovary (CHO) HCPs and residual protein A of in-process control samples and final drug substance. The ELISA setup is designed to serve three main goals: high sample throughput, high quality of results, and sample handling flexibility. The processing of analysis requests, determination of optimal sample dilutions, and calculation of impurity content is performed automatically by a spreadsheet. Up to 48 samples in three unspiked and spiked dilutions each are processed within 24 h. The dilution of each sample is individually prepared based on the drug concentration and the expected impurity content. Adaptable dilution protocols allow the analysis of sample dilutions ranging from 1:2 to 1:2×10(7). The validity of results is assessed by automatic testing for dilutional linearity and spike recovery for each sample. This automated impurity ELISA facilitates multi-project process development, is easily adaptable to other impurity ELISA formats, and increases analytical capacity by combining flexible sample handling with high data quality. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Cost-benefit analysis of the introduction of ELISA for the diagnosis of animal trypanosomosis in Africa

    International Nuclear Information System (INIS)

    Binsbergen, J.C. van; Schaik, G. van; Huirne, R.B.M.; Dwinger, R.H.

    2000-01-01

    Socio-economic data was requested by questionnaires from researchers in 15 different National Agricultural Research Systems (NARS). The results of the survey were analysed and used for a socio-economic cost-benefit analysis, comparing the costs of 'diagnosis, treatments and drug-resistance' in the two alternatives 'with' ELISA and the 'without' situation. The major assumptions of the cost-scheme used are: 1) an increase in the occurrence of drug-resistance if nothing changes in the current practice of drug-use; 2) large scale diagnosis in test and treatment practice, combined with the use of pour-on's, would lead to the abolishment of the current practice of administering prophylactic drugs. In order for this to be a feasible option, the development and subsequent promotion of Ag-ELISA and pour-on's is recommended. The first alternative, with BCT, has a slightly better cost-benefit ratio (1:53) than the second alternative, with Ag-ELISA (1:44). However, the latter is still considered the only feasible option because of the applicability of pen-side ELISA on local level and the low cost allowing for cost-price savings. The budgetary restrictions for the use of BCT and its labour-intensiveness explain the relatively small amount of diagnoses in current practice. (author)

  7. Evaluation of the Standard Diagnostics Leptospira IgM ELISA for diagnosis of acute leptospirosis in Lao PDR

    NARCIS (Netherlands)

    Tanganuchitcharnchai, Ampai; Smythe, Lee; Dohnt, Michael; Hartskeerl, Rudy; Vongsouvath, Manivanh; Davong, Viengmone; Lattana, Olay; Newton, Paul N.; Blacksell, Stuart D.

    2012-01-01

    The diagnostic utility of the Standard Diagnostics Leptospira IgM ELISA for detection of acute leptospirosis was assessed in febrile adults admitted in Vientiane, Laos. Using the cut-off suggested by the manufacturer [optical density (OD) >= 0.75], the assay demonstrated limited diagnostic capacity

  8. EVALUATION OF ELISA METHOD TO DETECTION OF COW β-LACTOGLOBULIN IN SHEEP MILK AND SHEEP MILK PRODUCTS

    Directory of Open Access Journals (Sweden)

    Juraj Paulov

    2010-11-01

    Full Text Available The aim of work was to optimalize the ELISA method to detect the adulteration of sheep milk and sheep milk products by cow milk in the laboratory. We have focused on laboratory testing of ELISA kit (β-Lactoglobulin ELISA Set, SEDIUM R&D for detection of cow β-Lg in sheep milk order to obtain high-quality, reliable and economically advantageous method suitable for routine use in practice. The results shown that for the quality of adulteration determination  it is necessary to verify the sensitivity of applied kit by the samples dilution in accordance with the producer declared quantification range contained in the manual ELISA kit. The starting point for obtaining of relevant data was to create separate regression curves with high deter­mination coefficient, which allowed to quickly and easily detect the cow milk additions in sheep milk, cloddish sheep and Slovak sheep cheese. doi:10.5219/78  

  9. A Modified ELISA Accurately Measures Secretion of High Molecular Weight Hyaluronan (HA) by Graves' Disease Orbital Cells

    Science.gov (United States)

    Krieger, Christine C.

    2014-01-01

    Excess production of hyaluronan (hyaluronic acid [HA]) in the retro-orbital space is a major component of Graves' ophthalmopathy, and regulation of HA production by orbital cells is a major research area. In most previous studies, HA was measured by ELISAs that used HA-binding proteins for detection and rooster comb HA as standards. We show that the binding efficiency of HA-binding protein in the ELISA is a function of HA polymer size. Using gel electrophoresis, we show that HA secreted from orbital cells is primarily comprised of polymers more than 500 000. We modified a commercially available ELISA by using 1 million molecular weight HA as standard to accurately measure HA of this size. We demonstrated that IL-1β-stimulated HA secretion is at least 2-fold greater than previously reported, and activation of the TSH receptor by an activating antibody M22 from a patient with Graves' disease led to more than 3-fold increase in HA production in both fibroblasts/preadipocytes and adipocytes. These effects were not consistently detected with the commercial ELISA using rooster comb HA as standard and suggest that fibroblasts/preadipocytes may play a more prominent role in HA remodeling in Graves' ophthalmopathy than previously appreciated. PMID:24302624

  10. Latent class analysis of bulk tank milk PCR and ELISA testing for herd level diagnosis of Mycoplasma bovis

    DEFF Research Database (Denmark)

    Nielsen, Per Kantsø; Petersen, Mette Bisgaard; Nielsen, Liza Rosenbaum

    2015-01-01

    of this study was to evaluate the herd-level diagnostic performance of an indirect ELISA test by comparison to a real-time PCR test when diagnosing M. bovis in cattle herds of bulk tank milk. Bulk tank milk samples from Danish dairy herds (N=3437) were analysed with both the antibody detecting BIO K 302 M...

  11. Development of an ELISA-based kit for the on-farm determination of progesterone in milk

    Czech Academy of Sciences Publication Activity Database

    Simerský, Radim; Swaczynová, Jana; Morris, David; Fránek, M.; Strnad, Miroslav

    2007-01-01

    Roč. 52, č. 1 (2007), s. 19-28 ISSN 0375-8427 Institutional research plan: CEZ:AV0Z50380511 Keywords : bovine milk * ELISA * oestrus Subject RIV: CE - Biochemistry Impact factor: 0.645, year: 2007 http://old.vri.cz/docs/vetmed/52-1-19.pdf

  12. Dot-ELISA affinity test: an easy, low-cost method to estimate binding activity of monoclonal antibodies

    Czech Academy of Sciences Publication Activity Database

    Svobodová, Z.; Jankovičová, B.; Horák, Daniel; Bílková, Z.

    2013-01-01

    Roč. 4, č. 3 (2013), 1000168_1-1000168_5 ISSN 2155-9872 R&D Projects: GA MŠk 7E12053; GA MŠk 7E09109 EU Projects: European Commission(XE) 246513 - NADINE; European Commission(XE) 228980 - CAMINEMS Institutional support: RVO:61389013 Keywords : dot-ELISA * affinity * monoclonal antibody Subject RIV: CD - Macromolecular Chemistry

  13. Monitoring of a tsetse and trypanosomosis control programme in plateau and Bauchi State, Nigeria, using antigen ELISA and parasitological techniques

    Energy Technology Data Exchange (ETDEWEB)

    Ajayi, S A; Ogedengbe, J D; Dogo, G I [National Veterinary Research Inst., Vom, Plateau State (Nigeria). Parasitology Div.; Frame, I A [London School of Hygiene and Tropical Medicine, London (United Kingdom). Dept. of Med. Parasitol

    1997-02-01

    Between July 1994 and January 1995 a total of 1153 samples were collected from cattle in Plateau and Bauchi State, Nigeria, and analyzed for the presence of trypanosome infections using parasitological (Buffy Coat Technique [BCT] and blood film smears) and serological techniques (Ag-ELISA). A simple random sampling technique was employed. Tsetse flies and other insects were trapped during the same period using NITSE and biconical traps. Twenty two tsetse flies (6 Glossina p. palpalis, 3 G. longipalpis and 13 G. tachinoides) were caught, identified and dissected to check for trypanosomal infections. The results obtained using parasitological techniques showed an average prevalence rate in the two states surveyed of 3.4%. The antigen-capture ELISA technique (Ag-ELISA) was used to analyze 280 serum samples which were negative for trypanosomes when checked by BCT. Of these samples none were positive for T. congolense and 4 (1.4%) were detected positive for T. brucei. A subset of 120 samples was analyzed for the presence of T. vivax and 3 (2.5%) were found to be positive. The relative specificity of the Ag-ELISA for T. brucei, T. congolense and T. vivax was 98.5% 100% and 97.5%, respectively. (author). 8 refs, 1 fig., 3 tabs.

  14. ELISA and ImmunoStrip® for detection of Phytophthora ramorum, P. kernoviae, and other Phytophthora species

    Science.gov (United States)

    Francisco J. Avila; Barbara Schoedel; Z. Gloria Abad; Michael D. Coffey; Cheryl Blomquist

    2009-01-01

    The goal of this work was to develop improved tools for the detection of Phytophthora ramorum and P. kernoviae for field and the laboratory use. ImmunoStrip® and ELISA were selected as the test formats for development. Presently, the diagnosis of sudden oak death (SOD) in the national survey of P. ramorum ...

  15. Quantitation of antibodies to nucleoribonucleoprotein by ELISA : relation between antibody levels and disease activity in patients with connective tissue disease

    NARCIS (Netherlands)

    Houtman, PM; Kallenberg, CGM; Limburg, PC; Huitema, MG; van Rijswijk, MH; The, TH

    1985-01-01

    We describe a solid-phase enzyme-linked immunosorbent assay (ELISA) for quantitation of antibodies to nucleoribonucleoprotein (nRNP/Sm). nRNP/Sm was purified from rabbit thymus acetone powder by immunoaffinity chromatography and characterized by counterimmunoelectrophoresis (CIE) and immunoblotting

  16. ELISA for complexes between urokinase-type plasminogen activator and its receptor in lung cancer tissue extracts

    DEFF Research Database (Denmark)

    de Witte, H; Pappot, H; Brünner, N

    1997-01-01

    A sandwich-type ELISA has been developed for the assessment of complexes between urokinase-type plasminogen activator (uPA) and its receptor (uPAR) in extracts of squamous cell lung carcinomas. The assay is based on a combination of rabbit polyclonal anti-uPA antibodies and a biotinylated mouse...... anti-uPAR monoclonal antibody (MAb). The detection limit of the assay is approximately 0.5 fmol/ml. A linear dose-response is obtained with up to 40 fmol/ml of uPA:uPAR complexes, while uPA and uPAR separately do not cause any response in the ELISA. A buffer which has been used previously for optimal...... extraction of uPAR yields the highest amounts of uPA:uPAR complexes. Absorption of tumor extracts with anti-uPA or anti-uPAR MAbs results in a complete disappearance of the ELISA signal, demonstrating the specificity of the ELISA. The recovery of chemically cross-linked uPA:uPAR complexes added to tumor...

  17. Constraining early and interacting dark energy with gravitational wave standard sirens: the potential of the eLISA mission

    International Nuclear Information System (INIS)

    Caprini, Chiara; Tamanini, Nicola

    2016-01-01

    We perform a forecast analysis of the capability of the eLISA space-based interferometer to constrain models of early and interacting dark energy using gravitational wave standard sirens. We employ simulated catalogues of standard sirens given by merging massive black hole binaries visible by eLISA, with an electromagnetic counterpart detectable by future telescopes. We consider three-arms mission designs with arm length of 1, 2 and 5 million km, 5 years of mission duration and the best-level low frequency noise as recently tested by the LISA Pathfinder. Standard sirens with eLISA give access to an intermediate range of redshift 1 ∼< z ∼< 8, and can therefore provide competitive constraints on models where the onset of the deviation from ΛCDM (i.e. the epoch when early dark energy starts to be non-negligible, or when the interaction with dark matter begins) occurs relatively late, at z ∼< 6. If instead early or interacting dark energy is relevant already in the pre-recombination era, current cosmological probes (especially the cosmic microwave background) are more efficient than eLISA in constraining these models, except possibly in the interacting dark energy model if the energy exchange is proportional to the energy density of dark energy.

  18. Use of IgG avidity ELISA to differentiate acute from persistent infection with Salmonella Dublin in cattle

    DEFF Research Database (Denmark)

    Hansen, K.R.; Nielsen, L.R.; Lind, Peter

    2006-01-01

    Aims: To investigate whether an immunoglobulin (Ig)G avidity ELISA can be used to differentiate between acute and persistent infection with Salmonella (S.) Dublin in cattle. To determine whether the IgG isotype, IgG(1) and IgG(2) responses in acute and persistent infections differ. Methods...

  19. Estimation of serum thyroglobulin using isotopic and non-isotopic methods: a comparison between RIA, IRMA and ELISA

    International Nuclear Information System (INIS)

    Ajay Kumar; Velumani, A.; Dandekar, S.R.; Shah, D.H.; Rajashekharrao, B.

    1997-01-01

    Three in-house immunoassays viz, RIA, IRMA and ELISA for estimation of serum Tg were compared for their assay characteristics and clinical utility. The inter- and intra-assay coefficient of variations of RIA and IRMA were comparable and were marginally better than that of ELISA. The sensitivity of IRMA was superior to RIA which in turn was superior than ELISA. Incubation time for both IRMA and ELISA was 4 h as compared to 90 h required for RIA. The enzyme conjugated antibody had longest shelf-life (9 months) followed by radiolabeled antibody (3 months) while radiolabeled Tg had shortest shelf-life (3 weeks). There was no interference from circulating anti-Tg autoantibodies in the RIA of Tg as compared to a gross underestimation observed in both sandwich methods. Assays correlated well with each other (r > 0.85, n=200) and had suitable clinical utility (sensitivity > 93% and specificity > 89%). Each assay though had its own merits and demerits, yet it served the clinical utility for an effective management of patients with differentiated thyroid carcinoma. (author)

  20. Monitoring of a tsetse and trypanosomosis control programme in plateau and Bauchi State, Nigeria, using antigen ELISA and parasitological techniques

    International Nuclear Information System (INIS)

    Ajayi, S.A.; Ogedengbe, J.D.; Dogo, G.I.; Frame, I.A.

    1997-01-01

    Between July 1994 and January 1995 a total of 1153 samples were collected from cattle in Plateau and Bauchi State, Nigeria, and analyzed for the presence of trypanosome infections using parasitological (Buffy Coat Technique [BCT] and blood film smears) and serological techniques (Ag-ELISA). A simple random sampling technique was employed. Tsetse flies and other insects were trapped during the same period using NITSE and biconical traps. Twenty two tsetse flies (6 Glossina p. palpalis, 3 G. longipalpis and 13 G. tachinoides) were caught, identified and dissected to check for trypanosomal infections. The results obtained using parasitological techniques showed an average prevalence rate in the two states surveyed of 3.4%. The antigen-capture ELISA technique (Ag-ELISA) was used to analyze 280 serum samples which were negative for trypanosomes when checked by BCT. Of these samples none were positive for T. congolense and 4 (1.4%) were detected positive for T. brucei. A subset of 120 samples was analyzed for the presence of T. vivax and 3 (2.5%) were found to be positive. The relative specificity of the Ag-ELISA for T. brucei, T. congolense and T. vivax was 98.5% 100% and 97.5%, respectively. (author). 8 refs, 1 fig., 3 tabs

  1. Control charts for identifying systematic errors using control sera to detect antibody to Salmonella in an indirect ELISA

    DEFF Research Database (Denmark)

    Bak, H.; Barfod, Kristen

    2008-01-01

    This study evaluated the preparation of Shewhart's control charts using the concept of rational subgroups for monitoring the Salmonella antibody ELISA used for surveillance of Danish pig herds. Control charts were prepared for a buffer control sample, a negative serum sample and a positive serum...

  2. Use of enzyme linked immunosorbent assay (ELISA) for the diagnosis of brucellosis in cattle in Yucatan, Mexico

    International Nuclear Information System (INIS)

    Dajer, A.; Gutierrez, E.; Zapata, D.

    1998-01-01

    Sera (247) from non-vaccinated brucellosis negative herds, 328 negative sera from Brucella abortus strain 19 vaccinated herds (brucellosis free), and 95 sera positive to the Rose Bengal test (RBT) and Complement Fixation test (CFT) from Brucella abortus-infected herds, were used to determine the relative sensitivity and specificity of a FAO/IAEA I-ELISA kit and the Rivanol Agglutination Test (RAT), using the CFT as a 'gold standard'. A threshold value for the I-ELISA was determined to be 37 PP using the mean plus 3 standard deviations of the negative sera from vaccinated animals. The I-ELISA showed a high relative sensitivity (100%) and a good relative specificity (92.5%), using the threshold determined for local conditions. The RAT gave a lower sensitivity value than the CFT (97.8%) and good specificity (99.3%). The I-ELISA could be used as a screening test under Yucatan conditions or as a confirmatory test in places where vaccination is not carried out. The RAT lacks sensitivity and is therefore not recommended for use in final stages of eradication programs but could be used in control programmes or early stages of eradication campaigns as a confirmatory test. (author)

  3. Evaluation of two commercial, rapid, ELISA kits testing or scrapie in retro-pharyngeal lymph nodes in sheep

    NARCIS (Netherlands)

    Kittelberger, R.; McIntuyre, L.; Watts, S.; MacDiarmid, S.; Hannah, M.J.; Jenner, J.; Bueno, R.; Swainsbury, R.; Langeveld, J.P.M.; Keulen, van L.J.M.; Zijderveld, van F.G.; Wemheuer, W.M.; Richt, J.A.; Sorenson, S.J.; Pigott, C.J.; O'Keefe, J.S.

    2014-01-01

    AIMS: To estimate the number of cases of scrapie that would occur in sheep of different prion protein (PrP) genotypes if scrapie was to become established in New Zealand, and to compare the performance of two commercially available, rapid ELISA kits using ovine retro-pharyngeal lymph nodes (RLN)

  4. ELISA MEASUREMENT OF STACHYLYSIN (TM) IN SERUM TO QUANTIFY HUMAN EXPOSURES TO THE INDOOR MOLD STACHYBOTRYS CHARTARUM

    Science.gov (United States)

    Antibodies were produced against the hemolytic agent stachylysin obtained from the mold Stachybotryis chartarum. These antibodies were used to develop two enzyme-linked immunosorbent assay (ELISA) methods for the analysis of stachylysin in human and rat sera and environmental sa...

  5. Performance of an ELISA and Indirect Immunofluorescence Assay in Serological Diagnosis of Zoonotic Cutaneous Leishmaniasis in Iran

    Directory of Open Access Journals (Sweden)

    Bahador Sarkari

    2014-01-01

    Full Text Available Serological assays have been extensively evaluated for diagnosis of visceral leishmaniasis (VL and considered as a routine method for diagnosis of VL while these methods are not properly evaluated for diagnosis of cutaneous leishmaniasis (CL. This study aimed to assess the performance of indirect immunofluorescent-antibody test (IFA and enzyme-linked immunosorbent assay (ELISA for serodiagnosis of cutaneous leishmaniasis in Iran. Sixty-one sera samples from parasitologically confirmed CL patients and 50 sera from healthy controls along with 50 sera from non-CL patients were collected. Antigen was prepared from promastigotes and amastigotes of Leishmania major. IFA was used to detect anti-Leishmania IgG while ELISA was used to detect anti-Leishmania IgM, total IgG, or IgG subclasses (IgG1 and 4. ELISA, for detection of total IgG and IgM, showed sensitivity of 83.6% and 84.7% and specificity of 62.7% and 54.6%, respectively. Sensitivity and specificity of ELISA for detecting IgG1 and IgG4 were 64%, 75% and 85%, 49%, respectively. Sensitivity and specificity of IFA were 91.6% and 81%. Conclusion. Findings of this study demonstrated that serological test, especially IFA, can be used for proper diagnosis of CL.

  6. A Laboratory Exercise to Illustrate Increased Salivary Cortisol in Response to Three Stressful Conditions Using Competitive ELISA

    Science.gov (United States)

    Haussmann, Mark F.; Vleck, Carol M; Farrar, Eugenia S.

    2007-01-01

    Perceived stress activates the hypothalamus-pituitary-adrenal axis, resulting in the release of glucocorticoids into the systemic circulation. Glucocorticoids cause the elevation of blood glucose, providing the necessary energy for the organism to cope with stress. Here, we outline a laboratory exercise that uses a competitive ELISA kit to…

  7. Pertussis serology: assessment of IgG anti-PT ELISA for replacement of the CHO cell assay*

    Science.gov (United States)

    DALBY, TINE; SØRENSEN, CHARLOTTE; PETERSEN, JESPER WESTPHAL; KROGFELT, KAREN ANGELIKI

    2010-01-01

    Dalby T, Sørensen C, Petersen JW, Krogfelt KA. Pertussis serology: assessment of IgG anti-PT ELISA for replacement of the CHO cell assay. APMIS 2010; 118: 968–72. Two types of serological assays are commonly used for the assessment of pertussis vaccine-induced antibodies; the Chinese hamster ovary cell (CHO cell) assay and the immunoglobulin G (IgG) anti pertussis toxin (PT) enzyme-linked immunosorbent assay (IgG anti-PT ELISA). Recently, both the techniques have been modified to improve performance with sera with interfering activity (CHO cell assay) or with heat-treated sera (IgG anti-PT ELISA). These two improved techniques were compared by the analysis of 100 individual serum samples from a previous clinical trial and 213 sera from a longitudinal serum collection from 20 Danish adults recently vaccinated with the Danish acellular pertussis vaccine. The comparison showed a significant linear correlation between the results of the two assays with a p-value of ELISA can be used as a replacement for the often troublesome and time-consuming CHO cell assay for the measurement of vaccine-induced human antibodies to PT. PMID:21091778

  8. Immunological Tools: Engaging Students in the Use and Analysis of Flow Cytometry and Enzyme-linked Immunosorbent Assay (ELISA)

    Science.gov (United States)

    Ott, Laura E.; Carson, Susan

    2014-01-01

    Flow cytometry and enzyme-linked immunosorbent assay (ELISA) are commonly used techniques associated with clinical and research applications within the immunology and medical fields. The use of these techniques is becoming increasingly valuable in many life science and engineering disciplines as well. Herein, we report the development and…

  9. Diagnostic Value of ELISA Tests for the Detection of Specific Antibodies in Cats and Rabbits with Dermatophytosis

    Directory of Open Access Journals (Sweden)

    Marinka Drobnič-Košorok

    2002-01-01

    Full Text Available Two indirect ELISA tests developed for the detection of specific IgG in cats and rabbits, infected with M. canis and T. mentagrophytes, respectively, were evaluated and compared. The levels of specific antibodies were determined in sera of 20 cats and 25 rabbits naturally infected with M. canis and T. mentagrophytes, respectively. Infection was confirmed by the results of fungal culture. Blood samples from 12 cats and 17 rabbits, previously unexposed to dermatophytes, served as negative controls. A significant increase in the level of specific antibodies in groups of infected animals was demonstrated. Sensitivity, specificity and predictive values of a positive and a negative test were determined to evaluate the diagnostic potential. ELISA for the detection of specific antibodies in cats infected with M. canis (ELISA-cats test exhibited 75.0 % of sensitivity at 91.7 % of specificity, whereas the test for the detection of specific antibodies in rabbits, infected with T. mentagrophytes (ELISA-rabbits test is highly sensitive (96.0 % and highly specific (94.1 %, confirming its encouraging diagnostic potential. The cross-reactivity of fungal antigens was tested by performing the assays with antigens M. canis, T. mentagrophytes, M. pachydermatis and A. fumigatus. There were no significant indications of cross-reactions in the test T. mentagrophytes-rabbits, whereas strong cross-reaction between dermatophyte antigens was observed in the test M. canis-cats.

  10. Development & standardization of an in-house IgM indirect ELISA for the detection of parvovirus B19 infections

    Directory of Open Access Journals (Sweden)

    Kumaran Vadivel

    2017-01-01

    Interpretation & conclusions: The in-house IgM indirect ELISA was found to be simple with high sensitivity and specificity when compared with nPCR and could be used as an alternative to expensive commercial kits in resource-poor settings.

  11. Comparison of ELISA, nested PCR and sequencing and a novel qPCR for detection of Giardia isolates from Jordan.

    Science.gov (United States)

    Hijjawi, Nawal; Yang, Rongchang; Hatmal, Ma'mon; Yassin, Yasmeen; Mharib, Taghrid; Mukbel, Rami; Mahmoud, Sameer Alhaj; Al-Shudifat, Abdel-Ellah; Ryan, Una

    2018-02-01

    Little is known about the prevalence of Giardia duodenalis in human patients in Jordan and all previous studies have used direct microscopy, which lacks sensitivity. The present study developed a novel quantitative PCR (qPCR) assay at the β-giardin (bg) locus and evaluated its use as a frontline test for the diagnosis of giardiasis in comparison with a commercially available ELISA using nested PCR and sequencing of the glutamate dehydrogenase (gdh) locus (gdh nPCR) as the gold standard. A total of 96 human faecal samples were collected from 96 patients suffering from diarrhoea from 5 regions of Jordan and were screened using the ELISA and qPCR. The analytical specificity of the bg qPCR assay revealed no cross-reactions with other genera and detected all the Giardia isolates tested. Analytical sensitivity was 1 Giardia cyst per μl of DNA extract. The overall prevalence of Giardia was 64.6%. The clinical sensitivity and specificity of the bg qPCR was 89.9% and 82.9% respectively compared to 76.5 and 68.0% for the ELISA. This study is the first to compare three different methods (ELISA, bg qPCR, nested PCR and sequencing at the gdh locus) to diagnose Jordanian patients suffering from giardiasis and to analyze their demographic data. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Casipoemas por Navidad : (1969-2010)

    OpenAIRE

    Sena Medina, Guillermo

    2011-01-01

    PRESENTACIÓN AL AIRE DE LA POESÍA RELIGIOSA Y NAVIDEÑA DE GUILLERMO SENA MEDINA Constituye un gran honor hacer la presentación de Guillermo Sena Medina por un doble motivo; por la larga y sincera amistad que nos une desde hace muchos años al socaire de nuestra común afición por la Historia, como cronistas oficiales de nuestros municipios; y, sobre todo y particularmente, por su rica y profunda personalidad como hombre de letras, nacida de su aún más rica y profunda personalidad humana. A...

  13. Evaluation of a serological test (indirect ELISA) for the diagnosis of sarcoptic mange in red foxes (Vulpes vulpes).

    Science.gov (United States)

    Bornstein, Set; Frössling, Jenny; Näslund, Katarina; Zakrisson, Göran; Mörner, Torsten

    2006-12-01

    Sarcoptic mange occurs in many parts of the world and is common in populations of domestic and wild canids, including red foxes (Vulpes vulpes). In recent years, an indirect antibody enzyme-linked immunosorbent assay (ELISA), with higher sensitivity and specificity than traditional diagnostic methods, has been successfully applied in the diagnosis of sarcoptic mange in dogs. The same ELISA has also demonstrated specific antibodies to Sarcoptes scabiei in experimentally infected red foxes. The aim of this study was to evaluate the indirect ELISA when used to detect antibodies to S. scabiei in field sera from Swedish red foxes. One cohort of both infected and non-infected red foxes (cohort 1; n = 88), and one cohort of apparently non-infected foxes (cohort 2; n = 67) were examined for skin lesions and presence of S. scabiei by thorough visual examination at autopsy and skin scrapings. Samples of blood-tinted body liquid from the abdomen or thorax cavity were collected and analysed by the indirect ELISA. The relative sensitivity and specificity of the ELISA at different cut-offs (OD values) were estimated by comparing the test results to the infection status as determined by examination and skin scrapings. The highest combination of relative sensitivity and specificity, calculated based on cohort 1, was 95.4 and 100.0%, respectively. These estimates were constant for cut-offs 0.150-0.225, which included the cut-off based on the mean plus three standard deviations of test results from cohort 2 (0.165). It is concluded that this test can be useful in diagnosis and epidemiological studies of S. scabiei infection in red foxes.

  14. Development of an Aquaporin-4 Orthogonal Array of Particle-Based ELISA for Neuromyelitis Optica Autoantibodies Detection.

    Directory of Open Access Journals (Sweden)

    Francesco Pisani

    Full Text Available Serological markers of Nuromyelitis Optica (NMO, an autoimmune disorder of the central nervous system, are autoantibodies targeting the astrocytic water channel aquaporin-4 (AQP4. We have previously demonstrated that the main epitopes for these autoantibodies (AQP4-IgG are generated by the supramolecular arrangement of AQP4 tetramers into an Orthogonal Array of Particles (OAPs. Many tests have been developed to detect AQP4-IgG in patient sera but several procedural issues affect OAP assembly and consequently test sensitivity. To date, the protein based ELISA test shows the lowest sensitivity while representing a valid alternative to the more sensitive cell based assay (CBA, which, however, shows economic, technical and interpretation problems. Here we have developed a high perfomance ELISA in which native OAPs are used as the molecular target. To this aim a native size exclusion chromatography method has been developed to isolate integral, highly pure and AQP4-IgG-recognized OAPs from rat brain. These OAPs were immobilized and oriented on a plastic plate by a sandwich approach and 139 human sera were tested, including 67 sera from NMO patients. The OAP-ELISA showed a 99% specificity and a higher sensitivity (91% compared to the CBA test. A comparative analysis revealed an end-point titer three orders of magnitude higher than the commercial ELISA and six times higher than our in-house CBA test. We show that CNS-extracted OAPs are crucial elements in order to perform an efficient AQP4-IgG test and the OAP-ELISA developed represents a valid alternative to the CBA currently used.

  15. Old and new diagnostic approaches for Q fever diagnosis: correlation among serological (CFT, ELISA) and molecular analyses.

    Science.gov (United States)

    Natale, A; Bucci, G; Capello, K; Barberio, A; Tavella, A; Nardelli, S; Marangon, S; Ceglie, L

    2012-07-01

    The objective of this study was to evaluate the performance of the complement fixation test (CFT) with respect to ELISA for the serological diagnosis of Q fever and to assess the role of serology as a tool for the identification of the shedder status. During 2009-2010, sera from 9635 bovines and 3872 small ruminants (3057 goats and 815 sheep) were collected and analyzed with CFT and ELISA. In addition, 2256 bovine, 139 caprine and 72 ovine samples (individual and bulk tank milk samples, fetuses, vaginal swabs and placentae) were analyzed with a real-time PCR kit. The relative sensitivity (Se) and specificity (Sp) of CFT with respect to ELISA were Se 26.56% and Sp 99.71% for cattle and Se 9.96% and Sp 99.94% for small ruminants. To evaluate the correlation between serum-positive status and shedder status, the ELISA, CFT and real-time PCR results were compared. Due to the sampling method and the data storage system, the analysis of individual associations between the serological and molecular tests was possible only for some of the bovine samples. From a statistical point of view, no agreement was observed between the serological and molecular results obtained for fetus and vaginal swab samples. Slightly better agreement was observed between the serological and molecular results obtained for the individual milk samples and between the serological (at least one positive in the examined group) and molecular results for the bulk tank milk (BTM) samples. The CFT results exhibited a better correlation with the shedder status than did the ELISA results. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Comparing validation of four ELISA-systems for detection of Salmonella derby- and Salmonella infantis-infected pigs.

    Science.gov (United States)

    Roesler, Uwe; Szabo, Istvan; Matthies, Claudia; Albrecht, Kerstin; Leffler, Martin; Scherer, Kathrin; Nöckler, Karsten; Lehmann, Jörg; Methner, Ulrich; Hensel, Andreas; Truyen, Uwe

    2011-01-01

    The objective of this study was the comparative evaluation of four indirect Salmonella ELISA tests at study time approved in Germany to detect Salmonella infection in pigs.Three tests are based on a LPS-antigen mix and directed against specific IgG antibodies. The fourth test is based on a purified S. Typhimurium whole-cell lysate antigen and discriminates between Salmonella-specific IgM-, IgA-, and IgG- antibodies. In a longitudinal study, two groups of six weeks old hybrid piglets were orally infected with a porcine S. Infantis or S. Derby strain. Clinical and bacteriological parameters were monitored weekly during an observation period of 130 days after infection and serum samples were investigated in parallel with the respective ELISAs. Apparently, the LPS-based ELISA systems used in this study failed to recognize S. Infantis-infected pigs although those animals shed the pathogen in high amounts throughout the study until day 81 post infection (p. i.). In contrast, the isotype-specific Salmonella Typhimurium whole-cell-lysate based ELISA was capable of detecting Salmonella-infected pigs from day ten p. i. at all tested serotypes and revealed the highest sensitivity in detection of S. Infantis-infected pigs. Furthermore, it became apparent that the often used surveillance cut-off value of 40 OD% is not appropriate for intra-vitam detection of S. Infantis- and S. Derby-infected pigs. In contrast, the cut-off values of the ELISAs given by the suppliers result in considerable higher detection rates.

  17. Synthesis and processing of ELISA polymer substitute: The influence of surface chemistry and morphology on detection sensitivity

    Science.gov (United States)

    Hosseini, Samira; Ibrahim, Fatimah; Djordjevic, Ivan; Rothan, Hussin A.; Yusof, Rohana; van der Marel, Cees; Koole, Leo H.

    2014-10-01

    Despite the known drawbacks of enzyme-linked immunosorbent assay (ELISA), one of the deficiencies that have relatively been ignored is the performance of ELISA substrate itself. Polystyrene (PS), as the cost effective material of choice for mass production of ELISA well-plates, has shown obvious lacks of suitable physical and chemical properties for protein attachment. The general concept of this work was to develop a potential substrate that can be suggested as a material of choice for production of a new generation of ELISA analytical kits. Spin-coated thin films of polymethyl methacrylate-co-methacrylic acid (PMMA-co-MAA) on silicon surfaces were designed and processed for detection of dengue virus. Coated surfaces of different molar ratios have been investigated as carboxyl-functionalized layers for obtaining platform for biomolecule immobilization with high level of protein activity. To improve the sensitivity of detection, we have used amine functional "spacers", hexamethylenediamine (HMDA) and polyethyleneimine (PEI), which were covalently bonded to the surfaces of PMMA-co-MAA coatings. Results demonstrate that the variation of surface concentration of carboxyl groups of PMMA-co-MAA can be used to control the amine surface concentration after carbodiimide coupling with HMDA and PEI spacers. The presence of amine spacers increases hydrophilicity of the coatings and significantly impacts the polymer surface morphology. In particular, protein immobilization via amine-bearing spacers has been achieved in two effective steps: (1) carbodiimide bonding between amine spacer molecules and PMMA-co-MAA polymer coatings; and (2) covalent immobilization of antibody via glutaraldehyde reaction with amine groups from amine-treated surfaces. The application of PEI spacer in comparison to HMDA has shown much higher intensity of detection signal in ELISA experiment, indicating better immobilization efficiency and preservation of antibody activity upon attachment to the

  18. Development of an Indirect ELISA Based on a Recombinant Chimeric Protein for the Detection of Antibodies against Bovine Babesiosis.

    Science.gov (United States)

    Jaramillo Ortiz, José Manuel; Montenegro, Valeria Noely; de la Fournière, Sofía Ana María; Sarmiento, Néstor Fabián; Farber, Marisa Diana; Wilkowsky, Silvina Elizabeth

    2018-01-23

    The current method for Babesia spp. serodiagnosis based on a crude merozoite antigen is a complex and time-consuming procedure. An indirect enzyme-linked immunosorbent assay (iELISA) based on a recombinant multi-antigen of Babesia bovis (rMABbO) was developed for detection of antibodies in bovines suspected of infection with this parasite. The multi-antigen comprises gene fragments of three previously characterized B. bovis antigens: MSA-2c, RAP-1 and the Heat Shock protein 20 that are well-conserved among geographically distant strains. The cutoff value for the new rMABbo-iELISA was determined using 75 known-positive and 300 known-negative bovine sera previously tested for antibodies to B. bovis by the gold-standard ELISA which uses a merozoite lysate. A cutoff value of ≥35% was determined in these samples by receiver operator characteristic (ROC) curve analysis, showing a sensitivity of 95.9% and a specificity of 94.3%. The rMABbo-iELISA was further tested in a blind trial using an additional set of 263 field bovine sera from enzootic and tick-free regions of Argentina. Results showed a good agreement with the gold standard test with a Cohen's kappa value of 0.76. Finally, the prevalence of bovine babesiosis in different tick enzootic regions of Argentina was analyzed where seropositivity values among 68-80% were obtained. A certain level of cross reaction was observed when samples from B. bigemina infected cattle were analyzed with the new test, which can be attributed to shared epitopes between 2 of the 3 antigens. This new rMABbo-iELISA could be considered a simpler alternative to detect anti Babesia spp. antibodies and appears to be well suited to perform epidemiological surveys at the herd level in regions where ticks are present.

  19. Comparsion of an immunochromatographic strip with ELISA for simultaneous detection of thiamphenicol, florfenicol and chloramphenicol in food samples.

    Science.gov (United States)

    Guo, Lingling; Song, Shanshan; Liu, Liqiang; Peng, Juan; Kuang, Hua; Xu, Chuanlai

    2015-09-01

    Rapid and sensitive indirect competitive enzyme-linked immunosorbent assays (ic-ELISA) and gold nanoparticle immunochromatographic strip tests were developed to detect thiamphenicol (TAP), florfenicol (FF) and chloramphenicol (CAP) in milk and honey samples. The generic monoclonal antibody for TAP, FF and CAP was prepared based on a hapten [D-threo-1-(4-aminophenyl)-2- dichloroacetylamino-1,3-propanediol], and the haptenwas linked to a carrier protein using the diazotization method. After the optimization of several parameters (coating, pH, sodium chloride content and methanol content), the ic-ELISA was established. The quantitative working range for TAP was 0.11-1.36 ng/mL, with an IC50 of 0.39 ng/mL. The optimized ELISA showed cross-reactivity to CAP (300%) and FF (15.6%), with IC50 values of 0.13 and 2.5 ng/mL, respectively. The analytical recovery of TAP, FF and CAP in milk and honey samples in the ic-ELISA ranged from 81.2 to 112.9%. Based on this monoclonal antibody, a rapid and sensitive immunochromatographic test strip was also developed. This strip had a detection limit of 1 ng/mL for TAP, FF and CAP in milk and honey samples. Moreover, the test was completed within 10 min. Our results showed that the proposed ic-ELISA and immunochromatographic test strip method are highly useful screening tools for TAP, FF and CAP detection in milk and honey samples. Copyright © 2015 John Wiley & Sons, Ltd.

  20. Expression, purification of metallothionein genes from freshwater crab (Sinopotamon yangtsekiense) and development of an anti-metallothionein ELISA

    Science.gov (United States)

    Zhang, Hao; Zhou, Hui

    2017-01-01

    Using the phoA-fusion technology, the recombinant metallothionein (MT) from freshwater crab (Sinopotamon yangtsekiense) has been successfully produced in Escherichia coli. MT purified from the bacterial suspension showed one polypeptide with a molecular weight of 7 kDa by tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis (Tricine-SDS-PAGE). Western-blotting confirmed the polypeptides had a specific reactivity with mouse polyclonal MT anti-serum. Based on the purified MT and MT anti-serum, the reaction parameters for an enzyme-linked immunosorbent assay (ELISA) were developed. The direct coating ELISA showed a higher linear relationship compared to antibody sandwich coating ELISA. The optimal dilution rates of purified MT anti-serum and coating period were shown to be 1:160,000 and 12 hours at 4°C. At 37°C, the appropriate reaction duration of the first antibody and the second antibody were 2 hours and 1 hour, respectively. According to these optimal parameters, the standard linear equation, y = 0.0032x + 0.1769 (R2 = 0.9779, x, y representing MT concentration and OD450 value), was established for the determination of MT concentration with a valid range of 3.9–500 ng/ml. In verification experiments, the mean coefficients of variation of the intra-assay and inter-assay were 3.260% and 3.736%, respectively. According to the result of MT recovery, ELISA with an approaching 100% MT recovery was more reliable and sensitive than the Cd saturation assay. In conclusion, the newly developed ELISA of this study was precise, stable and repeatable, and could be used as a biomarker tool to monitor pollution by heavy metals. PMID:28350826

  1. Development and validation of a quantitative competitive ELISA for potency testing of equine anti rabies sera with other potential use.

    Science.gov (United States)

    Korimbocus, Jehanara; Dehay, Nicolas; Tordo, Noël; Cano, François; Morgeaux, Sylvie

    2016-06-14

    In case of a bite by a rabies infected animal, the World Health Organisation recommends a prophylactic treatment including the administration of Human Rabies Immunoglobulins (HRIGs) or highly purified F(ab')2 fragments produced from Equine Rabies Immunoglobulin (F(ab')2 - ERIGs). According to international regulation, quality control of F(ab')2 - ERIGs lots requires potency testing by the in vivo Mouse Neutralisation Test (MNT) prior marketing. However, the strategy of the 3Rs (Reduce, Refine, Replace) for animal testing required by the European Directive encourages the replacement of the in vivo potency test by an in vitro assay. In this context, a competitive ELISA method (c-ELISA) has been developed by the Agence Nationale de Sécurité du Médicament et des Produits de Santé where F(ab')2 - ERIGs are in competition with a monoclonal antibody recognizing the trimeric native form of the rabies glycoprotein. After a full validation study, the c-ELISA has been applied to commercial batches of F(ab')2 - ERIGs. A correlation study with the MNT demonstrated a similarity between the two methods (r=0.751). Moreover, the c-ELISA method which does not need any species specific reagent has been applied to HRIGs potency testing as an alternative method to Rapid Fluorescent Focus Inhibition Test (RFFIT), thus avoiding the handling of live rabies virus in BSL3 containment. In conclusion, the c-ELISA has shown its potential to replace MNT and possibly RFFIT for the quantification of rabies immunoglobulin. After optimisation it may be used for the quantification of rabies immunoglobulin in any animal species, notably for rabies immunogenicity assay in mice. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. A High-Throughput, Precipitating Colorimetric Sandwich ELISA Microarray for Shiga Toxins

    Directory of Open Access Journals (Sweden)

    Andrew Gehring

    2014-06-01

    Full Text Available Shiga toxins 1 and 2 (Stx1 and Stx2 from Shiga toxin-producing E. coli (STEC bacteria were simultaneously detected with a newly developed, high-throughput antibody microarray platform. The proteinaceous toxins were immobilized and sandwiched between biorecognition elements (monoclonal antibodies and pooled horseradish peroxidase (HRP-conjugated monoclonal antibodies. Following the reaction of HRP with the precipitating chromogenic substrate (metal enhanced 3,3-diaminobenzidine tetrahydrochloride or DAB, the formation of a colored product was quantitatively measured with an inexpensive flatbed page scanner. The colorimetric ELISA microarray was demonstrated to detect Stx1 and Stx2 at levels as low as ~4.5 ng/mL within ~2 h of total assay time with a narrow linear dynamic range of ~1–2 orders of magnitude and saturation levels well above background. Stx1 and/or Stx2 produced by various strains of STEC were also detected following the treatment of cultured cells with mitomycin C (a toxin-inducing antibiotic and/or B-PER (a cell-disrupting, protein extraction reagent. Semi-quantitative detection of Shiga toxins was demonstrated to be sporadic among various STEC strains following incubation with mitomycin C; however, further reaction with B-PER generally resulted in the detection of or increased detection of Stx1, relative to Stx2, produced by STECs inoculated into either axenic broth culture or culture broth containing ground beef.

  3. [The comparison of two newborn cytomegalovirus IgG antibody screening ELISA kits].

    Science.gov (United States)

    Zhang, Shun-Xian; He, Xiao-Zhou; Wang, Shi-Wen; Wang, Xiao-Fang

    2013-10-01

    This study compared two newborn Cytomegalovirus (CMV) IgG antibody screening ELISA kits and evaluated the detection effectiveness of Abnova kit. CMV IgG antibodies were detected by both SeraQuest and Abnova kits from dried blood spot (DBS) samples of 488 newborn heel sticks. The detection abilities of these two kits were compared in different sample dilution concentrations. Relative detection effectiveness of the Abnova kit was defined by statistical method using the SeraQuest kit as a point of comparison. Compared to the SeraQuest screening test kit, the Abnova kit revealed a sensitivity of 98.9%, specificity of 78.6%, positive predictive value of 99.3%, negative predictive value of 68.8%, and the coincidence rate for these two screening test kits at 98.3%. The consistency check of both kits based on interpretation of the kappa statistic was relatively good. For the Abnova kit, the "area under the ROC curve" was 0.887, which indicates moderate accuracy. Abnova kit can be applied to newborn screening for congenital CMV infections. However, repeating the test for ambiguous results is suggested to increase the specificity and negative predictive value.

  4. An evaluation of ELISA using recombinant Brucella abortus bacterioferritin (Bfr) for bovine brucellosis.

    Science.gov (United States)

    Hop, Huynh Tan; Arayan, Lauren Togonon; Simborio, Hannah Leah; Reyes, Alisha Wehdnesday Bernardo; Min, WonGi; Lee, Hu Jang; Lee, Jin Ju; Chang, Hong Hee; Kim, Suk

    2016-04-01

    To date, detection of antibodies against the lipopolysaccharide portion is the backbone of most serodiagnostic methods for brucellosis screening. However this pose a risk for false positive reactions related to other pathogens especially that of Yersinia enterocolitica O:9 which has the most prominent cross reactivity with Brucella spp. In this study, cloning and expression of Brucella abortus bacterioferritin (Bfr) was accomplished by PCR amplification into an expression vector system, and purification of a recombinant B. abortus Bfr (rBfr). The immunogenicity of rBfr was confirmed by Western blot with Brucella-positive bovine serum. To determine whether rBfr has a potential benefit for use in the serodiagnosis of bovine brucellosis, rBfr-based ELISA was performed. Interestingly, rBfr was able to detect anti-Brucella antibodies in positive sera in a dependent manner of TAT values but did not show an immunoreaction with negative samples. Particularly, average OD492 values at the lowest, medium and highest TAT titer levels were 1.4, 2.2 and 2.6-fold increase compared with the cutoff value, respectively. The accuracy, specificity and sensitivity of rBfr showed 89.09%, 93.6% and 85.33%, respectively. These findings suggest that rBfr might be a good candidate for serological diagnosis development of bovine brucellosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Usefulness of serological ELISA assay forTaenia saginata to detect naturally infected bovines

    Directory of Open Access Journals (Sweden)

    Silvana de Cássia Paulan

    Full Text Available Bovine cysticercosis, a cosmopolitan disease caused by Taenia saginata, leads to economic losses due to carcass devaluation at slaughter. Sanitary inspection at slaughterhouses, the routine diagnostic method in Brazil, lacks the necessary sensitivity to detect the mildly infected cattle that are typically encoutered in Brazil. In this study we have tested cattle sera from animals diagnosed as positive and negative by veterianry inspection for (1 anti-parasite antibodies using metacestodes antigens (T. solium vesicular fluid and T. saginata secretions and (2 the HP10 secreted antigen of viable metacestodes. The cut-off values were calculated by ROC curve for intense and mild infections conditions, and by the classical method ( for negative samples. The sensitivity and specificity of these diagnostic tests were different depending on the assumed cut-off value and, importantly, whether the infection was mild or intense. In spite of these observations, however, such ELISA assays for serum antibodies and parasite antigens constitute an important tool for epidemiological porposes, and in establishing priorities for the control of bovine cysticercosis.

  6. Comparison between a Conductometric Biosensor and ELISA in the Evaluation of Johne’s Disease

    Directory of Open Access Journals (Sweden)

    Chika Okafor

    2014-10-01

    Full Text Available Johne’s disease (JD, caused by Mycobacterium avium subspecies paratuberculosis (MAP, is an important gastrointestinal disease of cattle worldwide because of the economic losses encountered in JD-affected herds. These losses include reduction in milk yield in cows, premature culling and reduced carcass weight of culled diseased animals. In the U.S. dairy industry, economic losses from reduced productivity associated with JD are estimated to cost between $200 and $250 million annually. The development of non-laboratory-based assays would support more frequent testing of animals for JD and could improve its control. Conductometric biosensors combine immunomigration technology with electronic signal detection and have been adapted for the detection of IgG antibody against MAP. In the present study, a capture membrane with limited variability in the immunomigration channel and an optimal concentration of the secondary anti-bovine antibody used in a previously developed conductometric biosensor were compared with a commercially available antibody detection ELISA in their evaluation of JD, using samples of serum from cattle whose JD status where unknown. There was a moderate strength of agreement (kappa = 0.41 between the two assays. Findings from this preliminary study support the continued development of conductometric biosensors for use in the diagnosis of JD.

  7. PrPSc detection in formalin-fixed paraffin-embedded tissue by ELISA

    Directory of Open Access Journals (Sweden)

    Nicholson Eric M

    2011-10-01

    Full Text Available Abstract Background Formalin-fixed paraffin-embedded tissue is regularly employed in the diagnosis of transmissible spongiform encephalopathies (TSE by immunohistochemistry (IHC, the standard by which all other TSE diagnostic protocols are judged. While IHC affords advantages over diagnostic approaches that typically utilize fresh or frozen tissue, such as Western blot and ELISA, the process of fixing, staining, and analyzing individual sections by hand does not allow for rapid or high throughput screening. However, preservation of tissues in formalin is not dependent upon the availability of refrigeration. Findings Formalin-fixed paraffin-embedded tissues from TSE transmission studies of scrapie in sheep, chronic wasting disease in white-tailed deer or transmissible mink encephalopathy in cattle were cut at 5 μm thickness. Samples containing the tissue equivalent of as little as one 5 μm section can be used to readily discriminate positive from negative samples. Conclusions This approach cannot replace IHC but may be used along with IHC as both a more rapid and readily high throughput screen where fresh or frozen tissues are not available or impractical.

  8. Preparation of anti-ciguatoxin monoclonal antibodies using synthetic haptens: sandwich ELISA detection of ciguatoxins.

    Science.gov (United States)

    Tsumuraya, Takeshi; Fujii, Ikuo; Hirama, Masahiro

    2014-01-01

    Ciguatera fish poisoning (CFP) is a form of food poisoning caused by the consumption of fish that have accumulated a type of sodium channel activator toxin called ciguatoxins (CTXs), which are produced by dinoflagellates of the genus Gambierdiscus through the food chain. CFP affects more than 50000 people each year. The extremely low level of CTXs in tainted fish has hampered the development of antibodies for the detection of these toxins. Monoclonal antibodies (mAbs) specific against major congeners of CTX3C, 51-hydroxyCTX3C, CTX1B, and 54-deoxyCTX1B were prepared by immunization of mice with protein conjugates of rationally designed synthetic haptens in place of the natural toxins. We found that haptenic groups possessing a surface area larger than 400 angstroms2 were required to produce mAbs that can bind strongly to CTXs. Direct sandwich ELISA utilizing two different monoclonal antibodies that bind specifically to one of the two wings of a CTX were established to detect CTXs. No cross-reactivity was observed against the other marine toxins tested, including brevetoxin A, brevetoxin B, okadaic acid, and maitotoxin.

  9. Validation of pre-coated ELISA tests to detect antibodies against T. congolense and T. vivax

    International Nuclear Information System (INIS)

    Shumba, W.

    2000-01-01

    The anti-trypanosomal antibody detecting enzyme linked immunosorbent assay (ELISA) was first described in 1977 and was further developed for use in large scale surveys in Zimbabwe. More recently, the IAEA initiated a programme to improve the robustness and standardisation of the assay. The IAEA supplied plates pre-coated with either a crude T. congolense or T. vivax antigen and the reagents necessary for analysing samples. Parasitologically positive and negative sera were used to validate and determine the cut-off values of the two tests. The samples were tested and results analysed using a variety of cut-off values. The tests provided similar information although the T. congolense pre-coated plates gave significantly higher optical density values than the plates coated with T. vivax. Sensitivity and specificity values were calculated using the different cut-off points. Results indicate that the test using T. congolense antigen had the highest specificity and sensitivity for a given cut-off value. Although the test could distinguish positive from negative sera, it was quite difficult to provide a suitable cut-off value, but the value should be dictated by the use of the test. (author)

  10. Antibodies to UV irradiated DNA: the monitoring of DNA damage by ELISA and indirect immunofluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Wani, A A; Gibson-D' Ambrosio, R E; D' Ambrosio, S M [Ohio State Univ., Columbus (USA). Dept. of Radiology

    1984-10-01

    The enzyme-linked immunosorbant assay (ELISA) was modified to (1) characterize antibodies raised in rabbits against UV-irradiated single-stranded DNA (UVssDNA) complexed with methylated BSA and (2) directly detect pyrimidine dimers in irradiated DNA. The antisera specifically bound to UVssDNA, UVpoly(dT) and to a limited extent to UVdsDNA and UVpoly(dC). Fifty per cent of the maximum antibody binding was observed at a 1-5000 dilution against UVssDNA. Binding to ssDNA and poly(dT) was observed only at much higher concentrations of antibody, whereas no binding to double stranded DNA (dsDNA) was observed. The extent of binding of the antibody was dependent on the UV dose to DNA and the concentration of antigen immobilized on the plate. The ability of various irradiated molecules, DNA, homopolymers and linkers to act as inhibitors of antibody binding establishes that the antigenic determinants are mainly thymine homodimers with lower affinity for cytosine dimers. Potential usefulness of the antibodies to directly quantitate pyrimidine dimers in cells exposed to UV radiation was determined by indirect immunofluorescence. Flow cytometric analysis of immunostained human lymphocytes irradiated with 254 nm radiation indicated that greater than 50% of the population had significantly higher fluorescent intensity than unirradiated cells.

  11. Development of an ELISA microarray assay for the sensitive and simultaneous detection of ten biodefense toxins.

    Energy Technology Data Exchange (ETDEWEB)

    Jenko, Kathryn; Zhang, Yanfeng; Kostenko, Yulia; Fan, Yongfeng; Garcia-Rodriguez, Consuelo; Lou, Jianlong; Marks, James D.; Varnum, Susan M.

    2014-10-21

    Plant and microbial toxins are considered bioterrorism threat agents because of their extreme toxicity and/or ease of availability. Additionally, some of these toxins are increasingly responsible for accidental food poisonings. The current study utilized an ELISA-based protein antibody microarray for the multiplexed detection of ten biothreat toxins, botulinum neurotoxins (BoNT) A, B, C, D, E, F, ricin, shiga toxins 1 and 2 (Stx), and staphylococcus enterotoxin B (SEB), in buffer and complex biological matrices. The multiplexed assay displayed a sensitivity of 1.3 pg/mL (BoNT/A, BoNT/B, SEB, Stx-1 and Stx-2), 3.3 pg/mL (BoNT/C, BoNT/E, BoNT/F) and 8.2 pg/mL (BoNT/D, ricin). All assays demonstrated high accuracy (75-120 percent recovery) and reproducibility (most coefficients of variation < 20%). Quantification curves for the ten toxins were also evaluated in clinical samples (serum, plasma, nasal fluid, saliva, stool, and urine) and environmental samples (apple juice, milk and baby food) with overall minimal matrix effects. The multiplex assays were highly specific, with little crossreactivity observed between the selected toxin antibodies. The results demonstrate a multiplex microarray that improves current immunoassay sensitivity for biological warfare agents in buffer, clinical, and environmental samples.

  12. Validation of a foot-and-mouth disease antibody ELISA in five Latin American countries

    International Nuclear Information System (INIS)

    Sondahl, M.S.; Penha Dias Gomes, M. da; Aurnheimer Martins, M.; Washington Lopez, J.

    1998-01-01

    The work plan consisted of using a liquid phase blocking ELISA test for the detection of antibodies to foot-and-mouth disease virus (FMDV) using the following categories of sera: (A) Spot test 120 non-infected/non-vaccinated bovine sera diluted 1:32; (B) Titration test: 120 bovine sera from animals vaccinated with trivalent oil vaccine, bled 30 days after vaccination; (C) Titration test with sera from non-infected/non-vaccinated bovines that presented titers >1:32 in the spot test. To detect FMD positive animals in the field, the spot test established with a cut-off of 1: 32 demonstrated in this work a good specificity with the non-vaccinated group, where 3 animals out of 120 were considered positive. The antibody titration test is an excellent tool to determine the level of antibodies in cattle populations. The protocol indicates that positive sera from the spot test should be tested in the titration assay in a starting dilution of 1:32. We suggest to use a lower starting dilution (1:16) in order to start below the discriminative of positive spot test sera 1:32 for the titration assay procedures. (author)

  13. The Electronic Logbook for the Information Storage of ATLAS Experiment at LHC (ELisA)

    CERN Document Server

    Corso-Radu, A; The ATLAS collaboration; Magnoni, L

    2012-01-01

    A large experiment like ATLAS at LHC (CERN), with over three thousand members and a shift crew of 15 people running the experiment 24/7, needs an easy and reliable tool to gather all the information concerning the experiment development, installation, deployment and exploitation over its lifetime. With the increasing number of users and the accumulation of stored information since the experiment start-up, the electronic logbook actually in use, ATLOG, started to show its limitations in terms of speed and usability. Its monolithic architecture makes the maintenance and implementation of new functionality a hard-to-almost-impossible process. A new tool ELisA has been developed to replace the existing ATLOG. It is based on modern web technologies: the Spring framework using a Model-View-Controller architecture was chosen, thus helping building flexible and easy to maintain applications. The new tool implements all features of the old electronic logbook with increased performance and better graphics: it uses the ...

  14. Diagnosis of gastritis caused by Helicobacter pylori in children by means of an ELISA.

    Science.gov (United States)

    Czinn, S J; Carr, H S; Speck, W T

    1991-01-01

    In this study, the systemic immune response to bacterial cell sonicates of Helicobacter pylori was characterized in children with symptomatic gastroduodenal disease. Isotype-specific antibodies to H. pylori in samples of serum from 16 children with culture-proven disease caused by H. pylori and from 19 controls with negative cultures were measured by ELISA with bacterial cell lysates. The levels in serum of IgA antibody to cell sonicates of H. pylori were significantly higher in the patients with positive cultures than in the controls. Only 45% of patients were infected when the established optical density cutoff was used to discriminate between patients infected and not infected with H. pylori. Levels of IgM antibody in serum were not significantly higher in patients who were infected with H. pylori. On the basis of this survey and of previous work conducted in our laboratory, we conclude that at a serum dilution of 1:800, IgG but not IgA or IgM antibody to H. pylori is useful in the rapid screening of symptomatic children for the presence of H. pylori.

  15. Comparison of a direct and indirect ELISA for quantitating antisperm antibody in semen.

    Science.gov (United States)

    Lynch, D M; Howe, S E

    1987-01-01

    A direct and an indirect quantitative ELISA for antisperm antibody were compared using the spermatozoa and cell-free seminal fluid of 66 infertile males. The normal concentration of sperm binding immunoglobulin was less than or equal to 1.5 fg Ig per spermatozoon for the indirect seminal plasma assay and less than or equal to 1.5 fg Ig per spermatozoon by the direct assay. Of the 66 infertile males, 21% (14/66) had elevated levels of antisperm antibody in their seminal plasma and 26% (17/66) had elevated levels bound directly to their spermatozoa. The direct correlation between the results of these assays was 94%. A simple linear regression analysis between the indirect and direct measurements of antisperm antibody resulted in a correlation coefficient of r = 0.907. There was no statistically significant difference between results from the direct and indirect methods of the patients as a group. However, there was evidence of autospecificity in a small percentage of males who had elevated levels of antisperm antibody by the direct assay that was not detected by the indirect assay using pooled donor spermatozoa.

  16. Development of a serodiagnostic IgM-ELISA for tick-borne encephalitis virus using subviral particles with strep-tag.

    Science.gov (United States)

    Nakayasu, Miki; Hirano, Minato; Muto, Memi; Kobayashi, Shintaro; Kariwa, Hiroaki; Yoshii, Kentaro

    2018-06-23

    Tick-borne encephalitis virus (TBEV) is a zoonotic agent causing severe encephalitis in humans. IgM antibody detection is useful for the serological diagnosis of TBEV infection, because IgM has high specificity for each flavivirus and indicates a recent infection. Commercial IgM-ELISA kits are somewhat expensive and difficulties in their sensitivity have been suggested due to their format and formalin-inactivated antigens. Therefore, the development of an inexpensive IgM-ELISA with high specificity and sensitivity is needed. In this study, a μ-capture ELISA was developed to detect TBEV-specific IgM antibodies using subviral particles (SPs) with strep-tag (strep-SP-IgM-ELISA). The results of our strep-SP-IgM-ELISA were highly correlated with diagnoses made by the neutralization test (sensitivity: 94.1%), and our strep-SP-IgM-ELISA could detect anti-TBEV IgM antibodies in patients who could not be diagnosed with the neutralization test. Besides, 51 of 52 positive samples by a commercial IgM-ELISA were also diagnosed as positive by our strep-SP-IgM-ELISA (98.1%), and our strep-SP-IgM-ELISA could detect anti-TBEV IgM antibodies in all samples that were inconclusive based on the commercial IgM-ELISA. Our strep-SP-IgM-ELISA will be useful for diagnoses in TBE-endemic areas. Copyright © 2018 Elsevier GmbH. All rights reserved.

  17. AN EVALUATION STUDY OF ENZYME-LINKED IMMUNOSORBENT ASSAY (ELISA USING RECOMBINANT PROTEIN GRA1 FOR DETECTION OF IGG ANTIBODIES AGAINTS TOXOPLASMA GONDII INFECTIONS

    Directory of Open Access Journals (Sweden)

    Nina Difla Muflikhah

    2017-08-01

    Full Text Available Toxoplasmosis is an infectious disease caused by Toxoplasma gondii, an intracellular protozoan parasite that live inside the cells of the reticulo endothelial and parenchymal cells of human and animals (mammals and birds. Some cases of toxoplasmosis usually have no symptoms, but in any cases caused severe symptoms, such as hydrocephalus, microcephalus, intracranial calcification, retinal damage, brain abscess, mental retardation, lymphadenopathy, and others. Its severe symptoms usually showed a long time after first exposure, except symptoms showed by congenital transmission caused by infected mother. Early diagnosis is important to prevent the illness but methods for toxoplasmosis screening are still too expensive for developing country. Enzyme-linked immunosorbent assay (ELISA allow the testing of a large number samples within short time frame and based on antibody or antigen detection. This study aimed to know the sensitivity and specificity of recombinat protein GRA1 as antigen using ELISA methods. We tested the sensitivity and spesificity of GRA1 protein as antigen in ELISA methods to diagnose toxoplasmosis and compared with ELISA Kit Commercial. Reliable laboratory testing is important to detect Toxoplasma gondii infection, and focused to improving the low cost and easy-to-use diagnostic instrument. Seventy sera collected and tested using both indirect ELISA, commercial ELISA kit and GRA1 protein coated as antigen. Fourty eight and fifty one samples showed positive IgG antibody result of ELISA-GRA1 and ELISA kit. Negative sample tested by ELISA-GRA1 was 22 samples and 19 sample tested by ELISA Kit. The sensitivity and specificity of GRA1-based on ELISA were 100% and 86.36%, positive prediction value (ppv was 94.11%. These data indicate that the recombinant protein GRA1 is a highly immunogenic protein in human toxoplasmosis and become a promising marker for the screening of toxoplasmosis.

  18. Hematoquecia letal por angiostrongilosis abdominal

    Directory of Open Access Journals (Sweden)

    Gerzain Rodríguez

    2000-06-01

    Full Text Available Una niña indigena de 4 años de edad, procedente de Carurú, Vaupés, un municipio semiselvático de 2.000 habitantes, presentó hematoquecia repetida con sincope y muerte 4 días después, a pesar de recibir transfusiones sanguíneas. El estudio postmortem descubrió dos masas de 3-4 cm de diámetro en el ileon distal que, al microscopio, correspondieron a inflamación severa de toda la pared intestinal, rica en eosinofilos y en granulomas con células gigantes que circunscribian y fagocitaban huevos y larvas de Angiostrongylus costaricensis, helminto situado también dentro de las arterias de la submucosa, vasos que presentaban engrosamiento de la intima y focos con inflamación granulomatosa con eosinófilos. La niña no presentó leucocitosis ni eosinofilia. Este es el segundo caso de angiostrongilosis de esta región. El primero fue el de una mujer indigena de 34 años también con hematoquecia anemizante. La angiostrongilosis abdominal se diagnosticó por primera vez en Colombia en 1979, en un niño de 5 años, de Dagua, Valle. La niña aquí presentada es el sexto paciente con esta entidad en Colombia. La hematoquecia como manifestación predominante de la angiostrongilosis es extraordinaria para una enfermedad parasitaria; se ha registrado solamente en tres ocasiones anteriores. La abundancia de cristales de Charcot-Leyden, que se tiñen muy bien con la coloración de Ziehl-Neelsen o de Fite-Faraco, en los infiltrados de la pared intestinal. sugiere que su búsqueda en las heces puede ser una ayuda en el diagnóstico de casos sospechosos. pues, los huevos y las larvas no se eliminan en las heces y el diagnóstico definitivo de la angiostrongilosis es histopatológico. Revisamos las caracteristicas clinicas, parasitológicas e histopatológicas de esta parasitosis que será más prevalente en Colombia a medida que los médicos. especialmente los patólogos, la conozcan mejor.

  19. Encefalopatía por priones

    Directory of Open Access Journals (Sweden)

    Carlos Colegial

    1999-01-01

    Full Text Available Las encefalopatías espongiformes por priones son enfermedades neurodegenerativas que pueden ser esporádicas o transmisibles, ya sea por mecanismos infecciosos o hereditarios. Su investigación ha planteado enormes retos y en el recorrido histórico en busca de su causa dos médicos han recibido el premio Nobel de Medicina: Carleton Gajdusek, por sus trabajos en Nueva Guinea donde describió la transmisión infecciosa por ritos canibalísticos, que llevó a estudios de transmisión experimental en chimpancés y a su teoría de los "virus lentos" (por el largo período de incubación de la enfermedad.

  20. Portable exhauster POR-007/Skid E and POR-008/Skid F storage plan

    International Nuclear Information System (INIS)

    Nelson, O.D.

    1998-01-01

    This document provides storage requirements for 1,000 CFM portable exhausters POR-O07/Skid E and POR-008/Skid F. These requirements are presented in three parts: preparation for storage, storage maintenance and testing, and retrieval from storage. The exhauster component identification numbers listed in this document contain the prefix POR-007 or POR-008 depending on which exhauster is being used