992 resultados para luorescent Treponemal Antibody Absorp- tion Assay
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AZEVEDO, Luciana Karla Araújo de, et al. Caracterização e correlação do fenômeno pró-zona com títulos de sororeatividade do VDRL e reação de imuno-fluorescência indireta em soros de pacientes com sífilis. Revista Brasileira de Análises Clínicas, Rio de Janeiro, v. 38, n. 2, p. 183-187, 2006.
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AZEVEDO, Luciana Karla Araújo de, et al. Caracterização e correlação do fenômeno pró-zona com títulos de sororeatividade do VDRL e reação de imuno-fluorescência indireta em soros de pacientes com sífilis. Revista Brasileira de Análises Clínicas, Rio de Janeiro, v. 38, n. 2, p. 183-187, 2006.
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AZEVEDO, Luciana Karla Araújo de, et al. Caracterização e correlação do fenômeno pró-zona com títulos de sororeatividade do VDRL e reação de imuno-fluorescência indireta em soros de pacientes com sífilis. Revista Brasileira de Análises Clínicas, Rio de Janeiro, v. 38, n. 2, p. 183-187, 2006.
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Os autores apresentam o caso clínico de um homem de 55 anos com antecedentes de sífilis primária na juventude e quatro reinfecções posteriores, a última das quais há dois anos, adequadamente tratada e com remissão do quadro. Observado em consulta externa de Oftalmologia, por olho vermelho, foi-lhe diagnosticada pan-uveíte, com íris de características sifilíticas (roséola sifilítica). Na sua avaliação laboratorial salientaram-se: Venereal Disease Research Laboratory (VDRL) positivo, Fluorescent Treponemal Antibody Absorbed Test (FTA-ABS) positivo, Vírus da Imunodeficiência Humana (VIH-1) positivo. Internado no Serviço de Medicina, foi submetido a punção lombar, tendo a análise do liquor revelado pleocitose, proteinorraquia aumentada, VDRL negativo, Treponema Pallidum Hemagglutination Assay (TPHA) positivo e FTA/ABS positivo, aspectos estes compatíveis com envolvimento sifilítico do SNC. O diagnóstico de neurosífilis assintomática nos doentes duplamente infectados é difícil e complexo, pois fundamenta-se em testes serológicos que não obedecem ao padrão habitual. A terapêutica é controversa, devido à recorrência dos quadros neurológicos após terapêuticas consideradas adequadas, sendo recomendada vigilância apertada destes doentes.
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A sífilis congênita (SC) vem ocupando um lugar de destaque no mundo todo, desde que se observou um aumento no número de casos a partir dos meados de 1980. Apesar do fato de ser uma doença perfeitamente prevenível, a SC permanece como um importante problema de saúde pública. O objetivo deste trabalho foi verificar a incidência de SC em neonatos. A pesquisa foi realizada na Maternidade da Fundação Santa Casa de Misericórdia do Pará (FSCMPA), no período de maio a setembro de 1996. Foram entrevistadas 361 mães e realizado o exame físico de seus recém-nascidos (RN). Os soros das puérperas e neonatos foram testados através de 3 métodos: um não treponêmico, Veneral Disease Research Laboratory (VDRL) e dois treponêmicos, Fluorescent Treponemal Antibody Absorption (FTA-Abs) e Enzime-Linked Immunosorbent Assay (ELISA) Imunoglobina M (IgM). Foi dado o diagnóstico de SC em 9,1% dos conceptos; no que diz respeito a outros fatores relacionados com a doença, encontrou-se que 39,4% dos recém natos com sífilis apresentaram algum sinal sugestivo da infecção; 36,4% das puérperas com sífilis não realizaram o pré-natal; 12,1% dessas puérperas confessaram consumir drogas e a maioria tinha história pregressa de natimortalidade e aborto; a bissexualidade paterna foi significativamente maior no que diz respeito aos recém natos com sífilis em comparação aos sem a moléstia. Investigações mais amplas devem ser realizadas para melhor compreensão das características epidemiológicas da infecção na região amazônica, e para adoção de medidas adequadas para controle e erradicação.
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Tick-borne encephalitis (TBE) is one of the most dangerous human neurological infections occurring in Europe and Northern parts of Asia with thousands of cases and millions vaccinated against it. The risk of TBE might be assessed through analyses of the samples taken from wildlife or from animals which are in close contact with humans. Dogs have been shown to be a good sentinel species for these studies. Serological assays for diagnosis of TBE in dogs are mainly based on purified and inactivated TBEV antigens. Here we describe novel dog anti-TBEV IgG monoclonal antibody (MAb)-capture assay which is based on TBEV prME subviral particles expressed in mammalian cells from Semliki Forest virus (SFV) replicon as well as IgG immunofluorescence assay (IFA) which is based on Vero E6 cells transfected with the same SFV replicon. We further demonstrate their use in a small-scale TBEV seroprevalence study of dogs representing different regions of Finland. Altogether, 148 dog serum samples were tested by novel assays and results were compared to those obtained with a commercial IgG enzyme immunoassay (EIA), hemagglutination inhibition test and IgG IFA with TBEV infected cells. Compared to reference tests, the sensitivities of the developed assays were 90-100% and the specificities of the two assays were 100%. Analysis of the dog serum samples showed a seroprevalence of 40% on Åland Islands and 6% on Southwestern archipelago of Finland. In conclusion, a specific and sensitive EIA and IFA for the detection of IgG antibodies in canine sera were developed. Based on these assays the seroprevalence of IgG antibodies in dogs from different regions of Finland was assessed and was shown to parallel the known human disease burden as the Southwestern archipelago and Åland Islands in particular had considerable dog TBEV antibody prevalence and represent areas with high risk of TBE for humans.
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One of the main difficulties related to the detection of the Hepatitis Delta Virus (HDV) antigen and antibody has been the source of the needed HD antigen since HDV containing human and animal livers are very difficult to obtain and since yield is low. This fact prompted us to try to use the serum of patients in the acute phase of HDV infection as a source of HDAg and turn to enzyme immunoassays (EIA) instead of RIA for the sake of easiness and economy in the amount of HDAg needed. The antigen for EIA was obtained from patients during the acute phase of HDV infection and the antibody from patients who have been carriers for many years. For the detection of the antigen, a sandwich type method was employed, whereas for the antibody a competition assay was developed. In order to assess the relative specificity and sensibility of the test, the antibody assay was compared to a commercial RIA (C. RIA, Abbott) and to a non-commercial RIA (NC RIA). Forty-two sera were tested by the two methods and only in two cases discrepant results were obtained. Its is concluded that: 1) sera from patients in the acute and chronic phases of HDV infection can be used as source of both antigen and antibody, for immunoassays; 2) EIA and RIA have comparable relative specificity and sensibility and 3) EIA is easier to perform, cheaper, non-hazardous, has a longer shelf-life and saves scarce HDAg.
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Crude Toxoplasma gondii antigens represent raw material used to prepare reagents to be employed in different serologic tests for the diagnosis of toxoplasmosis, including the IgM and IgG indirect hemagglutination (IgG-HA and IgM-HA) tests. So far, the actual antigenic molecules of the parasite involved in the interaction with agglutinating anti-T. gondii antibodies in these tests are unknown. The absorption process of serum samples from toxoplasmosis patients with the IgG-HA reagent (G-toxo-HA) demonstrated that red cells from this reagent were coated with T. gondii antigens with Mr of 39, 35, 30, 27, 22 and 14 kDa. The immune-absorption process with the IgM-HA reagent (M-toxo-HA), in turn, provided antibody eluates which recognized antigenic bands of the parasite corresponding to Mr of 54, 35 and 30 kDa, implying that these antigens are coating red cells from this reagent. The identification of most relevant antigens for each type of HA reagent seems to be useful for the inspection of the raw antigenic material, as well as of reagent batches routinely produced. Moreover the present findings can be used to modify these reagents in order to improve the performance of HA tests for the diagnosis of toxoplasmosis
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Three GST fusion recombinant antigen of Treponema pallidum, described as GST-rTp47, GST-rTp17 and GST-rTp15 were analyzed by Western blotting techniques. We have tested 53 serum samples: 25 from patients at different clinical stages of syphilis, all of them presenting anti-treponemal antibody, 25 from healthy blood donors and three from patients with sexually transmitted disease (STD) other than syphilis. Almost all samples from patients with syphilis presented a strong reactivity with GST-rTp17 antigen. Some samples were non-reactive or showed a weak reaction with GST-rTp47 and/or GST-rTp15, and apparently there was no correlation with the stage of disease. There was no seropositivity among blood donors. No sample reacted with purified GST. We concluded that due to their specificity these recombinant antigens can be used as GST fusion protein for development of syphilis diagnostic assays.
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A sífilis é uma doença sexualmente transmitida, reconhecida como tal desde o século XVI, cujo agente etiológico é Treponema pallidum subespécie pallidum, para o qual não existe meio de cultura artificial. Sendo uma infecção com inúmeras manifestações clínicas, incluindo a fase de latência e não havendo uma técnica que possa ser um verdadeiro teste padrão, o seu diagnóstico clínico e laboratorial afigura-se muitas vezes difícil. Nesta tese foram avaliados vários testes Venereal Disease Research Laboratory (VDRL), Rapid Plasma Reagin Test (RPR), Treponema pallidum Hemaglutination Antibody (TPHA), Fluorescent Treponemal Antibody Absortion (FTA-Abs), Passive Particle Agglutination Test (TP.PA), teste imunoenzimática (SYPHILIS-EIA) e Western-blot para a pesquisa de anticorpos anti-Treponema pallidum e técnicas de biologia molecular reacção em cadeia da polimerase (PCR) para o diagnóstico da sífilis nos seus diferentes estádios, incluindo neurossífilis. Experimentaram-se várias sequências iniciadoras (47-F/47-R, polA-F/polA-R-(PE), KO3A/KO4 e polA-F/polA-R) para amplificação de fragmentos dos genes da lipoproteína de 47kDa e do ADN polimerase I, e diferentes tipos de amostras: exsudado de úlceras genitais e de lesões cutâneas de secundarismo, exsudado de biopsias do lóbulo da orelha, sangue total, plasma, soro e liquor. Foram também optimizadas técnicas de PCR para a genotipagem de Treponema pallidum (amplificação de um fragmento do gene tpr e do gene arp) as quais foram aplicadas em algumas amostras incluídas neste estudo. Com a técnica de RPR obtiveram-se resultados idênticos ao VDRL no sangue e no liquor, pelo que parece que ambas as técnicas podem ser indiscriminadamente utilizadas nos dois tipos de produtos. Com os testes treponémicos obtiveram-se também, resultados semelhantes no liquor e no sangue. No entanto, as diferenças encontradas indicam que: a) o FTA-Abs, o Western-blot e o TP.PA devem ser os testes a utilizar nas fases precoces da infecção; b) o teste EIA parece indicado no caso de um grande número de amostras; c) o TP.PA e o TPHA podem ser utilizados na rotina laboratorial e, o primeiro eventualmente, também, na monitorização da terapêutica; d) o FTA-Abs e o Western-blot são os testes treponémicos que, de preferência devem ser utilizados no diagnóstico de neurossífilis embora os resultados do TP.PA se comparem aos do TPHA, no caso da infecção do sistema nervoso central por Treponema pallidum. A co-infecção com o VIH parece, ter efeito apenas, na reactividade dos testes não treponémicos, ocasionando falsa reactividade, independentemente da existência simultânea de toxicodependência. Em relação à técnica de PCR para o diagnóstico de sífilis, e para as várias sequências iniciadoras experimentadas os melhores resultados obtiveram-se com o par KO3A/KO4. A sensibilidade da técnica de PCR e de genotipagem nas amostras das úlceras genitais e das lesões cutâneas de sífilis secundária foi de 100%, o mesmo não acontecendo quando as técnicas se aplicaram à identificação de Treponema pallidum no sangue e no liquor, pelo que a técnica de PCR aplicada a este tipo de amostras necessita de ser aperfeiçoada. No entanto o exsudado de biopsia do lóbulo da orelha, seguida do plasma são os produtos, em que mais vezes, se identificou ADN de Treponema pallidum. O genótipo de Treponema pallidum subespécie pallidum mais frequentemente encontrado foi o 14c, sendo que o genótipo 10a foi pela primeira vez identificado no presente estudo.
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Background:It has been suggested that the relative importance of oestrogen-metabolising pathways may affect the risk of oestrogen-dependent tumours including endometrial cancer. One hypothesis is that the 2-hydroxy pathway is protective, whereas the 16α-hydroxy pathway is harmful.Methods:We conducted a case-control study nested within three prospective cohorts to assess whether the circulating 2-hydroxyestrone : 16α-hydroxyestrone (2-OHE1 : 16α-OHE1) ratio is inversely associated with endometrial cancer risk in postmenopausal women. A total of 179 cases and 336 controls, matching cases on cohort, age and date of blood donation, were included. Levels of 2-OHE1 and 16α-OHE1 were measured using a monoclonal antibody-based enzyme assay.Results:Endometrial cancer risk increased with increasing levels of both metabolites, with odds ratios in the top tertiles of 2.4 (95% CI=1.3, 4.6; P(trend)=0.007) for 2-OHE1 and 1.9 (95% CI=1.1, 3.5; P(trend)=0.03) for 16α-OHE1 in analyses adjusting for endometrial cancer risk factors. These associations were attenuated and no longer statistically significant after further adjustment for oestrone or oestradiol levels. No significant association was observed for the 2-OHE1 : 16α-OHE1 ratio.Conclusion:Our results do not support the hypothesis that greater metabolism of oestrogen via the 2-OH pathway, relative to the 16α-OH pathway, protects against endometrial cancer.
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Data obtained during the past five years have indicated that there are important age- and gender-based differences in the regulation and action of leptin in humans. To study the physiological changes of leptin during puberty in both sexes, and its relationship with body composition and sexual maturation, we measured leptin concentrations in 175 healthy adolescents (80 girls, 95 boys, 10-18 years of age), representing all pubertal stages. We excluded individuals with a body mass index (BMI) below the 5thor above the 95th percentile relative to age. Serum concentrations of leptin were determined by a monoclonal antibody-based immunofluorimetric assay, developed in our laboratory. Body composition was determined by dual-energy X-ray absorptiometry. Pubertal stage was assigned by physical examination, according to Tanner criteria for breast development in females and genital development in males. Leptin concentration in girls (N = 80) presented a positive linear correlation with age (r = 0.35, P = 0.0012), BMI (r = 0.65, P < 0.0001) and %fat mass (r = 0.76, P < 0.0001). In boys (N = 95) there was a positive correlation with BMI (r = 0.49, P < 0.0001) and %fat mass (r = 0.85, P < 0.0001), but a significant negative linear correlation with Tanner stage (r = -0.45, P < 0.0001) and age (r = -0.40, P < 0.0001). The regression equation revealed that %fat mass and BMI are the best parameters to be used to estimate leptin levels in both sexes. Thus, the normal reference ranges for circulating leptin during adolescence should be constructed according to BMI or %fat mass to assure a correct evaluation.
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In this study, we aimed to determine the prevalence and risk factors associated to Toxoplasma gondii infection in sheep from northeastern Brazil. A total of 932 ovine serum samples from 54 properties in 19 municipalities of the state of Sergipe were collected and assayed using indirect fluorescent antibody test. The assay used antibodies against Toxoplasma gondii (IFAT-IgG) with a cutoff point of 1:64. We observed that 28.22% (263/932) of the ovine samples were serum-reactive. In a logistic regression, factors such as consumption of water directly from the source, consumption of water from a deep well, and age below 12 months were associated with protection; whereas factors such as presence of cats on the property, presence of slatted floor, and use of exchanged or borrowed breeding males were associated with infection. The studied area can be considered endemic for toxoplasmosis, so it is necessary to adopt preventive and control measures because this zoonotic infection poses risks to public health.
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Syphilis is a sexually transmitted infectious disease caused by Treponema pallidum. This study reports 3 cases of syphilis and highlights the importance of identifying oral lesions for its final diagnosis. Case 1: a 48-year-old male patient presented with a bleeding ulcer in the lower lip. Overall clinical examination revealed patchy alopecia and skin target lesions. Case 2: a 61-year-old male patient presented with white spots on the lateral tongue and nodules on the dorsum of the tongue. Overall clinical examination showed erythematous target lesions on the abdomen, forearm, palms of the hand, and soles of the feet. Case 3: a 17-year-old male patient presented with an ulcerated lesion on the tongue and lymph node involvement. The following serologic tests were requested: Venereal Disease Research Laboratory, fluorescent treponemal antibody-absorption, anti-HIV-1 and anti-HIV-2, and anti-hepatitis C virus. An incisional biopsy revealed epithelial hyperplasia associated with intense and diffuse mononuclear inflammatory cell infiltration consisting mainly of plasma cells, in a perivascular and perineural distribution. The final diagnosis in the 3 patients was syphilis. Treatment consisted of 1 weekly dose of penicillin (2.4 million units, intramuscular) for 2 or 3 weeks. Immunohistochemical reactions for XIIIa, CD3, CD20, CD68, CD163, S100, CD1a, CD11c, CD83, CD138, and CD208 were performed. Clinicians should be familiarized with oral syphilis lesions in order to be able to diagnose this emerging infectious disease of variable clinical presentation.
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Elintarviketeollisuudessa tärkeimpiä pakkausmateriaaleja ovat erilaiset kartonkipakkaukset ja erityisesti niiden kuljetuksessa käytettävät aaltopahvipakkaukset. Aaltopahvilta vaadittavia ominaisuuksia ovat muun muassa puristuslujuus ja kosteudenkestävyys. Elintarvikekäyttöön tarkoitetuilla aaltopahveilla on myös tiettyjä vaatimuksia niissä käytettävistä yhdisteistä. Erilaiset kuitumateriaalit käyttäytyvät vettyessään eri tavalla ja niistä voi liueta yhdisteitä pakattavaan elintarvikkeeseen. Työn tavoitteena oli selvittää vettymiseen vaikuttavia tekijöitä ja veden vaikutus aaltopahvin rakenteeseen. Havaittiin, että ligniiniä tai uuteaineita sisältävä mekaanisesti valmistettu kartonkimateriaali ei sido vettä yhtä paljon kuin kemiallisesti valmistettu tai valkaistu kartonki. Aaltopahvissa tapahtuvan kapillaariabsorptio sai veden nousemaan pääasiassa aallotuskartonkiin. Vesi imeytyi korkeammalle puolikemiallisesti valmistetuissa aaltopahveissa kuin keräyskartonkipahveissa, jotka eivät myöskään turvonneet yhtä voimakkaasti. Työssä kartoitettiin myös elintarvikekäyttöä rajoittavia liukoisia yhdisteitä, jotka löytyivät paperiteollisuudessa yleisesti käytetyistä liimoista. Tällaisia yhdisteitä olivat märkälujaliimojen formaldehydiyhdisteet ja polyamidoamiini-epikloorihydriinihartsi. Keräyskartongin joukossa olevat raskasmetallit rajoittavat myös niiden käyttöä elintarvikepakkauksissa.