Positive selection results in frequent reversible amino acid replacements in the G protein gene of human respiratory syncytial virus.

Human respiratory syncytial virus (HRSV) is the major cause of lower respiratory tract infections in children under 5 years of age and the elderly, causing annual disease outbreaks during the fall and winter. Multiple lineages of the HRSVA and HRSVB serotypes co-circulate within a single outbreak and display a strongly temporal pattern of genetic variation, with a replacement of dominant genotypes occurring during consecutive years. In the present study we utilized phylogenetic methods to detect and map sites subject to adaptive evolution in the G protein of HRSVA and HRSVB. A total of 29 and 23 amino acid sites were found to be putatively positively selected in HRSVA and HRSVB, respectively. Several of these sites defined genotypes and lineages within genotypes in both groups, and correlated well with epitopes previously described in group A. Remarkably, 18 of these positively selected tended to revert in time to a previous codon state, producing a "flip-flop" phylogenetic pattern. Such frequent evolutionary reversals in HRSV are indicative of a combination of frequent positive selection, reflecting the changing immune status of the human population, and a limited repertoire of functionally viable amino acids at specific amino acid sites.

The impact of vitamin A supplementation on the immune system of vitamin A-deficient children.

BACKGROUND & AIMS: To investigate the effect of vitamin A supplementation on parameters of the immune system of vitamin A-deficient children. METHODS: The study was carried out in four phases: 1) determination of serum retinol in 631 children from 36 to 83 months of age; 2) assessment of immunological markers [immunoglobulins and complement fractions, immunophenotyping of T and B lymphocytes, and natural killer (NK) cells], blood count, and serum ferritin of 52 vitamin A-deficient children (serum retinol < 0.70 micromol/L); 3) supplementation of the 52 deficient children with 200,000 IU of vitamin A; 4) determination of serum retinol and the immunological parameters 2 months after vitamin A supplementation. RESULTS: before vitamin A supplementation, 24.0 % of the children were anemic and 4.3 %had reduced ferritin concentrations. There was no significant difference between mean values of retinol according to the presence/absence of anemia. The mean values of the humoral and cellular immunological parameters did not show a statistically significant difference before and after supplementation with vitamin A. Children with concomitant hypovitaminosis A and anemia presented a significant increase in absolute CD4 and CD8 T-cell counts after vitamin A supplementation (p < 0.05). CONCLUSION: vitamin A had an effect on the recruitment of T and B lymphocytes to the circulation of children with hypovitaminosis A and anemia.

[Prevalence and factors associated with vitamin A deficiency in preschool children from Teresina, Piauí, Brazil]. / Prevalência de deficiência de vitamina A e fatores associados em pré-escolares de Teresina, Piauí, Brasil.

Vitamin A deficiency is a public health problem in the Northeast of Brazil. This study aimed to determine the prevalence of vitamin A deficiency and associated factors among preschool children in Teresina, Piauí, Brazil. We studied the serum retinol levels and socioeconomic and demographic characteristics of 631 children from 36 to 83 months of age. The statistical association between each of the above characteristics and serum retinol levels was investigated by univariate and multivariate linear regression analysis. Mean serum retinol was 1.21 mmol/L (95%CI: 1.17-1.25 micromol/L) and was independent of gender (p = 0.259). Prevalence of vitamin A deficiency (retinol < 0.69 micromol/L) was 15.4% (95%CI: 12.7-18.4), with a tendency to decrease with age. Acceptable but not adequate retinol levels (0.70 to 1.04 micromol/L) were observed in 29% of children (95%CI: 25.2-32.4). There were positive associations between retinol levels and age, income, vitamin A supplementation, and maternal schooling. Vitamin A deficiency appeared as a moderately serious public health problem, emphasizing the importance of strategies to combat this problem in the region.

Parainfluenza virus as a cause of acute respiratory infection in hospitalized children.

BACKGROUND: Human parainfluenza viruses account for a significant proportion of lower respiratory tract infections in children. OBJECTIVE: To assess the prevalence of Human parainfluenza viruses as a cause of acute respiratory infection and to compare clinical data for this infection against those of the human respiratory syncytial virus. METHODS: A prospective study in children younger than five years with acute respiratory infection was conducted. Detection of respiratory viruses in nasopharyngeal aspirate samples was performed using the indirect immunofluorescence reaction. Length of hospital stay, age, clinical history and physical exam, clinical diagnoses, and evolution (admission to Intensive Care Unit or general ward, discharge or death) were assessed. Past personal (premature birth and cardiopathy) as well as family (smoking and atopy) medical factors were also assessed. RESULTS: A total of 585 patients were included with a median age of 7.9 months and median hospital stay of six days. No difference between the HRSV+ and HPIV+ groups was found in terms of age, gender or length of hospital stay. The HRSV+ group had more fever and cough. Need for admission to the Intensive Care Unit was similar for both groups but more deaths were recorded in the HPIV+ group. The occurrence of parainfluenza peaked during the autumn in the first two years of the study. CONCLUSION: Parainfluenza was responsible for significant morbidity, proving to be the second-most prevalent viral agent in this population after respiratory syncytial virus. No difference in clinical presentation was found between the two groups, but mortality was higher in the HPIV+ group.

Assessment of the rapid test based on an immunochromatography technique for detecting anti-Treponema pallidum antibodies.

A rapid test based on an immunochromatography assay - Determine Syphilis TP (Abbott Lab.) for detecting specific antibodies to Treponema pallidum was evaluated against serum samples from patients with clinical, epidemiological and serological diagnosis of syphilis, patients with sexually transmitted disease other than syphilis, and individuals with negative serology for syphilis. The Determine test presented the sensitivity of 93.6%, specificity of 92.5%, and positive predictive value and negative predictive value of 95.2% and 93.7%, respectively. One serum sample from patient with recent latent syphilis showed a prozone reaction. Determine is a rapid assay, highly specific and easy to perform. This technique obviates the need of equipment and its diagnostic features demonstrate that it may be applicable as an alternative assay for syphilis screening under some emergency conditions or for patients living in remote localities.

Parainfluenza virus as a cause of acute respiratory infection in hospitalized childrens

Background: Human parainfluenza viruses account for a significant proportion of lower respiratory tract infections in children.Objective: To assess the prevalence of Human parainfluenza viruses as a cause of acute respiratory infection and to compare clinical data for this infection against those of the human respiratory syncytial virus.Methods: A prospective study in children younger than five years with acute respiratory infection was conducted. Detection of respiratory viruses in nasopharyngeal aspirate samples was performed using the indirect immunofluorescence reaction. Length of hospital stay, age, clinical history and physical exam, clinical diagnoses, and evolution (admission to Intensive Care Unit or general ward, discharge or death) were assessed. Past personal (premature birth and cardiopathy) as well as family (smoking and atopy) medical factors were also assessed.Results: A total of 585 patients were included with a median age of 7.9 months and median hospital stay of six days. No difference between the HRSV+ and HPIV+ groups was found in terms of age, gender or length of hospital stay. The HRSV+ group had more fever and cough. Need for admission to the Intensive Care Unit was similar for both groups but more deaths were recorded in the HPIV+ group. The occurrence of parainfluenza peaked during the autumn in the first two years of the study.Conclusion: Parainfluenza was responsible for significant morbidity, proving to be the second-most prevalent viral agent in this population after respiratory syncytial virus. No difference in clinical presentation was found between the two groups, but mortality was higher in the HPIV+ group.

Estabilidade dos anticorpos anti-HIV em amostras de soro armazenadas por períodos de dois a dezoito anos / Stability of anti-HIV antibodies in serum samples stored for two to eighteen years periods

Introduction: The antibodies have an important role in the serodiagnosis, constituting the most widely used biomarkers to detect and confirm various diseases. Objective: To investigate the reproducibility of anti-human immunodeficiency virus (HIV) antibodies reactivity, to assess the stability of the sera samples stored at -20ºC for two to eighteen years. Method: Sera were collected in the period 1988-2004 for routine anti-HIV antibodies diagnostic testing. The remaining samples stored at -20ºC, were analyzed in this study. Serum sample stability was assessed by enzyme-linked immunosorbent assay/enzyme immunoassay (ELISA/EIA), indirect immunofluorescence assay (IFA), and Western blot (WB) for detecting anti-HIV antibodies. The previously found results (1988-2004) and those obtained in 2006 were subjected to Kappa index analysis. Result: In the period 1988-to 2004, the degree of concordance of the ELISA/EIA, IFA and WB results were considered, good (k = 0.80), regular (k = 0.35), and good (k = 0.63), respectively. Conclusion: Regarding HIV serologic test, the serum samples were stable for 18 years in ELISA/EIA and for 4 years in IFA technique, however, for the WB methodology it was not possible to determine the time of stability of the anti-HIV antibodies...

Introdução: Os anticorpos possuem papel fundamental no sorodiagnóstico e constituem os mais difundidos biomarcadores empregados na detecção e na confirmação de diversas doenças. Objetivo: Verificar a reprodutibilidade dos resultados de anticorpos contra o vírus da imunodeficiência humana (HIV) para avaliar a estabilidade dos soros armazenados a -20ºC durante período de dois a dezoito anos. Método: Os soros utilizados foram provenientes de amostras remanescentes da rotina diagnóstica para detecção de anticorpos anti-HIV, no período de 1988 a 2004, os quais estavam armazenados em freezer a -20ºC. A estabilidade das amostras de soro foi avaliada por meio de enzyme-linked immunosorbent assay/enzyme immunoassay (ELISA/EIA), imunofluorescência indireta (IFI) e Western blot (WB) para detecção de anticorpos anti-HIV, e os resultados dos testes realizados anteriormente (1988-2004) e os obtidos em 2006 foram submetidos à análise do índice Kappa. Resultado: No período de 1988-2004, os graus de concordância dos resultados do ELISA/EIA, IFI e WB foram considerados, respectivamente, bom (k = 0,80), regular (k = 0,35) e bom (k = 0,63). Conclusão: No que diz respeito à sorologia para HIV, as amostras de soro foram estáveis por 18 anos no ELISA/EIA e por quatro anos na técnica de IFI, no entanto, para a metodologia de WB, não foi possível determinar o tempo de estabilidade dos anticorpos anti-HIV...

Estudo de homogeneidade dos soros utilizados em controle de qualidade interno de testes imunodiagnósticos de HIV/Aids / AidsHomogeneity study of the internal quality control sera for immunodiagnosis of HIV/AIDS

Introduction: The present study reports the data from the first homogeneity assessment of samples composing the serum panels produced at the Immunology Center of Instituto Adolfo Lutz, São Paulo. These samples have been distributed to the public laboratories and those partaking in the Brazilian Unified Health System, and to the participants in the Internal Quality Control Program for human immunodeficiency virus (HIV) antibody (Ab) testing. Objective: To assess the homogeneity of serum samples in panels from different lots for HIV/acquired immunodeficiency syndrome (AIDS) immunodiagnosis by using the statistical method to ensure quality of the reference material. Method: Sera homogeneity was evaluated by means of enzyme-linked immunoassay/enzyme immunoassay (ELISA/EIA) for detection of HIV Ab, and the one-way analysis of variance was employed for analyzing the data. No statistically significant differences were found among the several serum vials. Conclusion: The sera dispensed in the vials were homogeneous in the respective lots...

Introdução: No presente estudo estão descritos os resultados das primeiras análises feitas sobre a avaliação da homogeneidade das amostras componentes de painéis de soros produzidos no Centro de Imunologia do Instituto Adolfo Lutz e distribuídos aos laboratórios públicos e conveniados ao Sistema Único de Saúde e participantes do Programa de Controle de Qualidade Interno para imunodiagnóstico de vírus da imunodeficiência humana/síndrome da imunodeficiência adquirida (HIV/AIDS). Objetivo: Avaliar a homogeneidade das amostras de soro componentes de painéis de diferentes lotes para imunodiagnóstico de HIV/Aids por meio de método estatístico para garantir a qualidade do material de referência. Material e método: A homogeneidade das amostras de soro foi avaliada por meio de enzyme-linked immunoassay/enzyme immunoassay (ELISA/EIA) para detecção de anticorpos anti-HIV, e os resultados foram submetidos à análise de variância fator único. Não foram encontradas diferenças significativas entre os resultados obtidos para os diversos frascos de soro. Conclusão: As amostras distribuídas nos frascos foram homogêneas entre si nos respectivos lotes...

Estabilidade dos soros para o controle de qualidade interno de testes imunodiagnósticos de HIV/AIDS / Study on the stability of internal quality control sera for HIV/AIDS immunodiagnostic tests

Introduction: The use of reference materials in order to assure and perform the quality control of analytical measurements is a requirement in clinical laboratories. Objectives: Stability of serum samples, kept frozen at -20°C for long-term storage and at varied temperatures during short periods, was evaluated by investigating the persistency of anti-human immunodeficiency virus (HIV) antibodies reactivity on enzyme-linked immunosorbent assay/enzyme immunoassay (ELISA/EIA), Western blot and indirect immunofluorescence assays. Method: The analyzed sera were part of serum panels (comprised of anti-HIV positive and negative samples), produced at the Immunology Center of Instituto Adolfo Lutz, which have been the reference specimens for producing the internal quality assurance sera of HIV/acquired immunodeficiency syndrome (AIDS) immunodiagnostic assays. Sera stability was assessed in samples stored at -20°C for 56 weeks, and at various temperature conditions: from 2°C to 8°C (refrigerator), from 15°C to 25°C (room temperature), at 37°C (incubator) and at -80°C (freezer) for 24 and 48 hours. The statistical analyses on HIV-negative serum samples (long-term storage) were significant (p < 0.05), and neither adverse effects on these samples as the occurrence of false-positive results nor false-negative results in HIV antibody positive sera were found in both studies. Conclusion: It was possible to conclude that the reference material remained stable for 48 hours at different temperatures (short-term) and it remained stable at -20°C for 56 weeks (long-term)...

Introdução: A utilização de materiais de referência para assegurar e desempenhar o papel de controle de qualidade das medições analíticas é requisito em laboratórios clínicos. Objetivo: O presente estudo avaliou a estabilidade das amostras de soro, armazenadas a -20°C por um longo período de tempo e durante curto prazo em diferentes temperaturas, quanto à invariabilidade da reatividade de anticorpos contra o vírus da imunodeficiência humana (HIV), por meio de enzyme-linked immunosorbent assay/enzyme immunoassay (ELISA/EIA), Western blot e imunofluorescência indireta. Método: As amostras analisadas foram provenientes de painéis de soros (constituídos de amostras anti-HIV positivo e negativo), produzidos no Centro de Imunologia do Instituto Adolfo Lutz (IAL), os quais têm sido material de referência para o preparo de amostras do controle de qualidade interno de testes imunodiagnósticos de HIV/síndrome da imunodeficiência adquirida (AIDS). A avaliação da estabilidade dos soros foi efetuada em amostras armazenadas a -20°C por 56 semanas e nas diferentes condições de temperaturas: de 2°C a 8°C (geladeira), de 15°C a 25°C (ambiente), 37°C (estufa) e -80°C (freezer), durante 24 e 48 horas. Os resultados das análises de tendência das amostras de soro HIV negativo (armazenamento de longo prazo) foram significantes (p < 0,05) e nenhum efeito adverso foi observado nessas amostras, como a ocorrência de resultados falso-positivos, tampouco foram detectados resultados falso-negativos em amostras de soro positivas para detecção de anticorpos anti-HIV em ambas as avaliações. Conclusão: Foi possível concluir que o material de referência manteve-se estável por 48 horas nas diferentes temperaturas (curto prazo) e permaneceu estável a -20°C por 56 semanas (longo prazo)...

Better CD4+ T cell recovery in Brazilian HIV-infected individuals under HAART due to cumulative carriage of SDF-1-3'A, CCR2-V64I, CCR5-D32 and CCR5-promoter 59029A/G polymorphisms.

Polymorphisms of chemokines and chemokine-receptors genes have been shown to influence the rate of progression to AIDS; however, their influence on response to HAART remains unclear. We investigated the frequency of the SDF-1-3'A, CCR2-64I, CCR5-D32 and CCR5-Promoter-59029-A/G polymorphisms in Brazilian HIV-1-infected and uninfected individuals and their influence on CD4+ T-cell evolution HIV-1 infected individuals before and during HAART. Polymorphism detection was done in a transversal study of 200 HIV-1-infected and 82 uninfected individuals. The rate of CD4+ T cell increase or decrease was studied in a cohort of 155 HIV-1 infected individuals on pre and post-HAART. Polymorphisms were determined by PCR associated with RFLP. The rate of CD4+ T-cell decline or increase was also determined. HIV-1 infected and uninfected subjects showed, respectively, frequencies of 0.193 and 0.220 for SDF-1-3'A, of 0.140 and 0.110 for CCR2-V64I, of 0.038 and 0.055 for CCR5-D32, and of 0.442 and 0.390 for CCR5-P-59029-A/G. HIV-1-infected subjects carrying one, two or three of these four polymorphisms showed better CD4+ T-cell recovery than HIV-1-infected subjects carrying the four wild-type alleles (+2.7, +1.6, +3.5, and -0.9 lymphocytes/microl/month, respectively). Regression logistic analysis showed that the CCR5-D32/CCR2-V64I association was predictor of positive CD4+ T cell slope after HAART. The distribution of polymorphisms did not differ between HIV-1-infected and uninfected individuals, but differed from more homogenous ethnic groups probably reflecting the miscegenation of the Brazilian population. We add further evidence of the role of these polymorphisms by showing that the CD4 gain was influenced by carriage of one or more of the polymorphisms studied here. These results highlight the possibility that these genetic traits can be useful to identify patients at risk for faster progression to AIDS or therapeutic failure.

Incidence and clinical characteristics of the infection by the respiratory syncytial virus in children admitted in Santa Casa de São Paulo Hospital.

The purpose of this study was to identify the rate of infections due to RSV and other viruses in children. In addition we have analyzed demographic data and clinical characteristics of the RSV-positive patients comparing with patients infected by other respiratory viruses. We also described the seasonality of the RSV occurrence in a hospital in São Paulo. Children below 5 years old admitted in Santa Casa de São Paulo Hospital between February 2005 and September 2006 due to acute respiratory infections (ARI) were included. A nasopharyngeal specimens were obtained with sterile No. 5 French feeding catheters as soon as possible (usually within 24 h). Specimens were kept refrigerated at 4 degrees C and transported to Adolfo Lutz Institute, where the indirect immunofluorescent assay was performed. Virus identified by these assay included RSV, Adenovirus, Influenza A and B virus and Parainfluenza 1, 2, and 3. Clinical data from each group was compared. Four hundred and fifty five cases were included in the study, with 30% positive for some type of virus. Viruses that were identified included Respiratory Syncytial Virus (73.03%), Influenza (8.42%), Parainfluenza (8.42%) and Adenovirus (3.37%). We divided the subjects in 3 groups: Group 1 RSV-Positive, Group 2 Other Positive Viruses and Group 3 Negative for Respiratory Virus. Mean age (months) was of 7.5 for RSV-positive children, 7.6 for other viruses, and 8 for negative for respiratory virus. The RSV-Positive Group was significantly younger than the Group Negative for Respiratory Virus (p<0.05). Signs of UAI were more present in the Positive RSV Group (p<0.05). General mortality was of 2.41%. There was a higher incidence of RSV between the months of March and August in the two years of the study. Our study indicates RSV as the most prevalent viral agent in children admitted due to (ARI), especially in infants below 3 months old. We have also found that infections due to RSV can occur in months others than the classic seasonal period.

Reatividade do anticorpo IgM anti-Treponema pallidum na soroconversão e na resposta sorológica ao tratamento de sífilis / IgM antibody reactivity to Treponema pallidum in seroconversion and in the serologic response to syphilis treatment

INTRODUÇÃO: A utilidade da detecção de anticorpos da imunoglobulina da classe M (IgM) no diagnóstico da sífilis tem sido discutida há tempos. OBJETIVO: No presente estudo foi analisada a ocorrência de anticorpo IgM anti-T. pallidum (Tp-IgMAc) nas amostras de pacientes com sífilis recente, na fase de soroconversão e no monitoramento da resposta sorológica pós-tratamento. MÉTODOS: Amostras séricas de 11 indivíduos. RESULTADOS: Na soroconversão, o Tp-IgMAc foi detectado nas amostras de 10 indivíduos, e em um paciente a reatividade IgM ocorreu anteriormente ao Venereal Disease Research Laboratory (VDRL). A sororreversão foi evidenciada nas amostras de três pacientes com sífilis secundária tratada, e em um indivíduo com reinfecção. CONCLUSÃO: A detecção de Tp-IgMAc mostrou ser um potencial marcador diagnóstico de sífilis ativa e o desempenho do ensaio imunoenzimático de captura de IgM (ELISA-IgM) para o monitoramento pós-tratamento foi similar ao da VDRL.

INTRODUCTION: The appropriateness of IgM antibody detection in the diagnosis of syphilis has been extensively discussed. OBJECTIVE: This study aimed at assessing the detection of anti-T. pallidum IgM antibody (TP-IgMAb) in serum samples from patients with recent syphilis in seroconversion and in the monitoring of post-treatment serological response. METHODS: Serum samples from 11 individuals. RESULTS: At seroconversion, positive Tp-IgMAb was detected in 10 samples and IgM reactivity previous to Venereal Disease Research Laboratory (VDRL) was detected in one sample. Seroreversion was found in samples from three treated patients with secondary syphilis and in one individual with reinfection. CONCLUSION: Tp-IgMAb detection proved to be a potential diagnostic marker for active syphilis, and IgM capture enzyme linked immunosorbent assay (ELISA-IgM) performance was similar to VDRL in post-treatment monitoring.

Rate and incidence estimates of recent human immunodeficiency virus type 1 infections among pregnant women in Sao Paulo, Brazil, from 1991 to 2002.

The serological testing algorithm for recent human immunodeficiency virus (HIV) seroconversion (STARHS) was employed to estimate HIV incidence among pregnant women from Sao Paulo, Brazil. A cross-sectional study (1999 to 2002) showed an incidence of infection of 0.2 per 100 pregnant women per year (95% confidence interval, 0.041 to 0.608). Western blot profiles suggested an association between results of the STARHS analysis and gp41/gp31 bands.

Incidence and clinical characteristics of the infection by the Respiratory Syncytial Virus in children admitted in Santa Casa de São Paulo Hospital

The purpose of this study was to identify the rate of infections due to RSV and other viruses in children. In addition we have analyzed demographic data and clinical characteristics of the RSV-positive patients comparing with patients infected by other respiratory viruses. We also described the seasonality of the RSV occurrence in a hospital in São Paulo. Children below 5 years old admitted in Santa Casa de São Paulo Hospital between February 2005 and September 2006 due to acute respiratory infections (ARI) were included. A nasopharyngeal specimens were obtained with sterile No. 5 French feeding catheters as soon as possible (usually within 24 h). Specimens were kept refrigerated at 4ºC and transported to Adolfo Lutz Institute, where the indirect immunofluorescent assay was performed. Virus identified by these assay included RSV, Adenovirus, Influenza A and B virus and Parainfluenza 1, 2, and 3. Clinical data from each group was compared. Four hundred and fifty five cases were included in the study, with 30 percent positive for some type of virus. Viruses that were identified included Respiratory Syncytial Virus (73.03 percent), Influenza (8.42 percent), Parainfluenza (8.42 percent) and Adenovirus (3.37 percent). We divided the subjects in 3 groups: Group 1 RSV-Positive, Group 2 Other Positive Viruses and Group 3 Negative for Respiratory Virus. Mean age (months) was of 7.5 for RSV-positive children, 7.6 for other viruses, and 8 for negative for respiratory virus. The RSV-Positive Group was significantly younger than the Group Negative for Respiratory Virus (p<0.05). Signs of UAI were more present in the Positive RSV Group (p<0.05). General mortality was of 2.41 percent. There was a higher incidence of RSV between the months of March and August in the two years of the study. Our study indicates RSV as the most prevalent viral agent in children admitted due to (ARI), especially in infants below 3 months old. We have also found that infections...

Prevalência de deficiência de vitamina A e fatores associados em pré-escolares de Teresina, Piauí, Brasil / Prevalence and factors associated with vitamin A deficiency in preschool children from Teresina, Piauí, Brazil

A deficiência de vitamina A constitui um problema de saúde pública no Nordeste brasileiro. O objetivo deste estudo foi determinar a prevalência da deficiência de vitamina A e os fatores associados em pré-escolares de Teresina, Piauí, Brasil. Os níveis de retinol sérico foram determinados por HPLC, e foram investigadas as características sócio-econômicas e demográficas de 631 crianças com idade de 36 a 83 meses. Investigou-se a associação entre os níveis de retinol e as variáveis de interesse por análise de regressão linear uni e multivariada. O nível médio de retinol foi de 1,21mmol/L (IC95 por cento: 1,17-1,25µmol/L), independente do sexo (p = 0,259). A hipovitaminose A (retinol < 0,69µmol/L) foi observada em 15,4 por cento das crianças (IC95 por cento: 12,7-18,4), com tendência à diminuição com o avanço da idade; 29 por cento das crianças (IC95 por cento: 25,2-32,4) tinham valores aceitáveis de retinol, mas não adequados (0,70 a 1,04µmol/L). Encontrou-se associação positiva entre níveis de retinol e idade, renda per capita, suplementação prévia com vitamina A e escolaridade materna. A prevalência de hipovitaminose A representa um problema moderado de saúde pública, ressaltando a importância das estratégias de combate a essa carência na região.

Penicilinoterapia intravenosa em altas doses na neurossífilis: III. Avaliaçäo de anticorpos antitreponêmicos da classe IgM no líquido cefalorraqueano e do soro / High-dose intravenous penicillin G in the treatment of neurosyphilis: III. Avaluation of antitreponemic antibodies of the IgM class in cerebrospinal fluid and serum

Anticorpos antitreponêmicos da classe IgM foram pesquisados no soro e no LCR de 9 casos de neurossífilis sintomática, antes e, em diversos momentos, depois do tratamento. Esses anticorpos foram investigados mediante reaçöes de imunofluorescência (IgM-FTA-Abs), hemadsorçäo em fase sólida e imunoenzimática (ELISA). Os títulos das reaçöes reduziram-se, mas houve persistência da reatividade no soro e no LCR no segundo ano após tratamento

Importância de Rattus norvegicus capturados no Município de São Paulo, SP, Brasil, como hospedeiros paratênicos de Toxocara canis (Ascaroidea, Nematoda) / Importance of Rattus norvegicus as parathenic hosts to Toxocara canis (Ascaroidea, Nematoda) in Sao Paulo, SP, Brazil

Analisaram-se os soros de 121 exemplares de Rattus noruetricus capturados no município de São Paulo, através de reação de hemaglutinação passiva, para pesquisar a presença de anticorpos anti-Toxocara, com a finalidade de avaliar o potencial destes roedores como hospedeiros paratênicos de Toxooara canis. Considerando como positivos os soros cujo título foi igualou superior a 1:20, em 28 ratos (23,120/0) revelaram-se anticorpos anti-Toxocara, indicando que é freqüente a infecção destes animais por T. canis em nosso meio e a possibilidade de atuarem estes murídeos como hospedeiros paratênicos para o nematóide (AU).

Assessment of the rapid test based on an immunochromatography technique for detecting anti-Treponema pallidum antibodies

A rapid test based on an immunochromatography assay - DetermineÕ Syphilis TP (Abbott Lab.) for detecting specific antibodies to Treponema pallidum was evaluated against serum samples from patients with clinical, epidemiological and serological diagnosis of syphilis, patients with sexually transmitted disease other than syphilis, and individuals with negative serology for syphilis. The DetermineÕ test presented the sensitivity of 93.6 percent, specificity of 92.5 percent, and positive predictive value and negative predictive value of 95.2 percent and 93.7 percent, respectively. One serum sample from patient with recent latent syphilis showed a prozone reaction. DetermineÕ is a rapid assay, highly specific and easy to perform. This technique obviates the need of equipment and its diagnostic features demonstrate that it may be applicable as an alternative assay for syphilis screening under some emergency conditions or for patients living in remote localities.

Passive haemagglutination test for human neuroCysticercosis immunodiagnosis: I. Standardization and evaluation of the passive haemagglutination test for the detection of anti-Cysticercus cellulosae antibodies

Foi padronizada e avaliada a reaçäo de hemaglutinaçäo passiva (RHA) para pesquisa de anticorpos específicos, anti-Cysticercus cellulosae, no líquido cefalorraquiano (LCR). Foram utilizadas hemácias humanas. O Rh-formolizadas e sensibilizadas com extrato antigênico salino total de cisticercos, ainda pouco estudado. De 115 amostras estudadas de LCR de pacientes com neurocisticercose, 94 foram reagentes, resultando em 81,7% de sensibilidade, com intervalo de confiança de 95% de probabilidade (IC95%) abrangendo de 74,5% e 88,9%. Também foram ensaiadas 89 amostras de LCR de indivíduos do grupo controle, sendo täo reagentes em 94,4%, com IC95%, de 89,6% a 99,2%. Os valores preditivos positivo e negativo obtidos para a RHA foram, respectivamente, de 14% e 99,9%, considerando a prevalência média de neurocisticercose na América Latina de 0,1%. Os resultados indicam que a RHA como um método simples, altamente reprodutível e moderadamente sensível para a detecçäo de anticorpos específicos no LCR, porém apropiados para a triagem de infectados

Passive Haemagglutination test for human neuroCysticercosis immunodiagnosis: I. Comparasion of two standardized procedures for the passive haemagglutination reagent in the detection of anti-Cysticercus cellulosae antibodies cerebrospinal fluids

Säo descritas duas metodologias para o preparo de reagente para a reaçäo de hemaglutinaçäo passiva (HRHA) destinada à pesquisa de anticorpos anti-Cysticercus cellulosae no líquido cefalorraquiano (LCR). Foram utilizadas hemácias humanas 0 Rh-formolizadas (HA-1) e hemácias de carneiro tratadas com glutaraldeído (HA-2), sensibilizadas com extrato antigênico salino total (ST) de cisticercos. Cento e quinze amostras de LCR de pacientes com neurocisticercose foram ensaiadas pelos testes HA-1 e HA-2, resultando em positividade de 81-7% e 88,7%, respectivamente. A especificidade obtida foi de 94,4% para HA-1 e 96,6% para HA-2. Näo foi observada diferença significativa quanto à capacidade diagnóstica dos reagentes na RHA em neurocisticercose (p < 0.05)