Usefulness of gel filtration fraction as potential biomarker for neurocysticercosis in serum: towards a new diagnostic tool.

There is an increasing interest in improving neurocysticercosis (NCC) diagnosis through the search of new and alternative antigenic sources, as those obtained from heterologous antigens. The aim of this study was to obtain potential biomarkers for NCC diagnosis after gel filtration chromatography [gel filtration fraction (GFF)] from the total saline extract (SE) from Taenia saginata metacestodes, followed by protein identification and application in immunodiagnostic. SE and GFF proteic profiles were characterized in gel electrophoresis, and diagnostic performance was verified by testing 160 serum samples through enzyme-linked immunosorbent assay and immunoblotting. Sensitivity (Se), specificity (Sp) and other diagnostic parameters were calculated. Polypeptides of interest in the diagnosis of human NCC present at GFF were analysed by mass spectrometry (MS) and B-cell epitopes were predicted. GFF had the best diagnostic parameters: Se 93·3%; Sp 93%; AUC 0·990; LR+ = 13·42 and LR- = 0·07, and proved to be useful reacting with serum samples in immunoblotting. Proteic profile ranged from 64 to 68 kDa and enolase and calcium binding protein calreticulin precursor were identified after MS. The enolase and calcium-binding protein calreticulin precursor showed 18 and 10 predicted B-cell epitopes, respectively. In conclusion we identified important markers in the GFF with high efficiency to diagnose NCC.

Ion-exchange protocol to obtain antigenic fractions with potential for serodiagnosis of strongyloidiasis.

The aim of this study was to fractionate and partially characterize the antigenic extract of filariform larvae of Strongyloides venezuelensis in ion-exchange resin diethylaminoethyl sepharose (DEAE), to obtain antigenic fractions potentially applicable in immunoassays. Somatic antigen (SA) and its fractions DEAE S1 and DEAE S2 - which interacted with the resin - were evaluated by 1-dimensional electrophoresis to obtain protein profiles. SA and its fractions were tested in serum samples for IgG detection by ELISA. Serum samples (n = 155) were analysed: 50 from strongyloidiasis patients (G1), 55 from patients with other parasitic infections (G2) and 50 from healthy volunteers. Sensitivity (Se), specificity (Sp), area under curve (AUC) and likelihood ratios (LR) were calculated. The DEAE S2 fraction provided a high diagnostic value for IgG detection (Se 92·0%, Sp 91·4%, AUC 0·981, LR+ 10·75, LR - 0·09). In conclusion, the DEAE S2 fraction would probably be a source of immunodominant polypeptides for IgG detection in human strongyloidiasis serodiagnosis.

Specific phage-displayed peptides discriminate different forms of neurocysticercosis by antibody detection in the serum samples.

Neurocysticercosis (NC), caused by Taenia solium metacestode, infects the central nervous system and is a devastating parasitic infection. Diagnosis is based on symptoms, imaging, serology and epidemiology. Current markers present variable sensitivity and specificity, frequent cross-reactions and are not able to discriminate NC clinical forms. The aim of this study was to select mimotopes of T. solium metacestode antigens that may be used in NC immunodiagnosis, specifically to discriminate between active and inactive forms. A random peptide phage display library was screened against IgY from chickens immunized with total saline extract from T. solium metacestodes and validated against 110 serum samples, classified into active NC (18), inactive NC (22), cross-reactive parasitic diseases (40) and healthy controls (30). We have successfully selected seven peptides with significant immunoreactivity to IgG of NC patients, with sensitivity ranging from 95.5% to 100% to detect the inactive form and specificity varied from 85.7% to 94.3%. One phage-displayed peptide (Cc48) can be directly used as biomarker to distinguish inactive from active forms with an accuracy of 95.7%, and this novel mimotope may also be used as an auxiliary tool to neuroimaging tests and treatment follow-up.

Why are the rates of cesarean section in Brazil higher in more developed cities than in less developed ones?

The objective of the present study was to investigate factors associated with cesarean sections in two cities located in different regions of Brazil and to determine factors that explain the higher cesarean section rate in the more developed city, Ribeirão Preto, compared to the less developed one, São Luís. Data from two cohort studies comprising 2846 women in Ribeirão Preto in 1994, and 2443 women in São Luís in 1997/1998 were used. Adjusted and non-adjusted risk estimates were calculated using a Poisson regression model. The cesarean section rate was 33.7 percent in São Luís and 50.8 percent in Ribeirão Preto. Adjusted analysis in a joint sequential model revealed a 51 percent higher risk of cesarean section in Ribeirão Preto compared to São Luís (prevalence rate ratio (PRR) = 1.51). Adjustment for category of hospital admission reduced the PRR to 1.09, i.e., this variable explained 82 percent of the difference in the cesarean section rate between the two cities. Adjustment for the variable "the same physician for prenatal care and delivery" reduced the PRR to 1.07, with the "physician" factor explaining 86 percent of the difference between rates. When simultaneously adjusted for the two variables, the PRR decreased to 1.05, with these two variables explaining 90 percent of the difference in the cesarean section rate between the two cities, and the difference was no longer significant. The difference in the cesarean section rate between the two Brazilian cities, one more and one less developed, was mainly explained by the physician factor and, to a lesser extent, by the category of hospital admission.

Do socioeconomic factors explain why maternal smoking during pregnancy is more frequent in a more developed city of Brazil?

The prevalence of smoking during pregnancy in Ribeirão Preto, a rich Brazilian city, was significantly higher (21.4 percent) than in São Luís (5.9 percent), a less developed city. To assess which variables explain the difference in prevalence of smoking during pregnancy, data from two birth cohorts were used, including 2846 puerperae from Ribeirão Preto, in 1994, and 2443 puerperae from São Luís, in 1997/98. In multivariable analysis, risk of maternal smoking during pregnancy was higher in São Luís for mothers living in a household with five or more persons (OR = 1.72, 95 percentCI = 1.12-2.64), aged 35 years or older (OR = 1.98, 95 percentCI = 0.99-3.96), who had five or more children (OR = 2.10, 95 percentCI = 1.16-3.81), and whose companion smoked (OR = 2.20, 95 percentCI = 1.52-3.18). Age of less than 20 years was a protective factor (OR = 0.55, 95 percentCI = 0.33-0.92). In Ribeirão Preto there was association with maternal low educational level (OR = 2.18, 95 percentCI = 1.30-3.65) and with a smoking companion (OR = 3.25, 95 percentCI = 2.52-4.18). Receiving prenatal care was a protective factor (OR = 0.24, 95 percentCI = 0.11-0.49). Mothers from Ribeirão Preto who worked outside the home were at a higher risk and those aged 35 years or older or who attended five or more prenatal care visits were at lower risk of smoking during pregnancy as compared to mothers from São Luís. Smoking by the companion reduced the difference between smoking rates in the two cities by 10 percent. The socioeconomic variables in the model did not explain the higher prevalence of smoking during pregnancy in the more developed city.

Inadequate utilization of prenatal care in two Brazilian birth cohorts

Data for two birth cohorts from two Brazilian municipalities, Ribeirão Preto in 1994 and São Luís in 1997/1998, were used to identify and compare factors associated with inadequate utilization of prenatal care and to identify factors capable of explaining the differences observed between the two cities. Prenatal care was defined as adequate or inadequate according to the recommendations of the Brazilian Ministry of Health. The chi-square test and Poisson regression were used to compare differences in the inadequacy of prenatal care utilization. The percentage of inadequacy was higher in São Luís (34.6 percent) than in Ribeirão Preto (16.9 percent). Practically the same variables were associated with inadequacy in both cities. Puerperae with lower educational level, without a companion or cohabiting, who delivered in public health units, younger than 20 years, multiparae and smokers, with low family income presented higher percentages of inadequate prenatal care utilization. However, the effects of some variables differed between the two cities. The risk for inadequate use of prenatal care was higher for women attended in the public health sector in São Luís and for cohabiting women in Ribeirão Preto. The effect of the remaining factors studied did not differ between cities. The category of admission accounted for 57.0 percent of the difference in the inadequate use of prenatal care between cities and marital status accounted for 45.3 percent of the difference. Even after adjustment for all variables, part of the difference in the inadequacy of prenatal care utilization remained unexplained.

Do socioeconomic factors explain why maternal smoking during pregnancy is more frequent in a more developed city of Brazil?

The prevalence of smoking during pregnancy in Ribeirão Preto, a rich Brazilian city, was significantly higher (21.4%) than in São Luís (5.9%), a less developed city. To assess which variables explain the difference in prevalence of smoking during pregnancy, data from two birth cohorts were used, including 2846 puerperae from Ribeirão Preto, in 1994, and 2443 puerperae from São Luís, in 1997/98. In multivariable analysis, risk of maternal smoking during pregnancy was higher in São Luís for mothers living in a household with five or more persons (OR = 1.72, 95%CI = 1.12-2.64), aged 35 years or older (OR = 1.98, 95%CI = 0.99-3.96), who had five or more children (OR = 2.10, 95%CI = 1.16-3.81), and whose companion smoked (OR = 2.20, 95%CI = 1.52-3.18). Age of less than 20 years was a protective factor (OR = 0.55, 95%CI = 0.33-0.92). In Ribeirão Preto there was association with maternal low educational level (OR = 2.18, 95%CI = 1.30-3.65) and with a smoking companion (OR = 3.25, 95%CI = 2.52-4.18). Receiving prenatal care was a protective factor (OR = 0.24, 95%CI = 0.11-0.49). Mothers from Ribeirão Preto who worked outside the home were at a higher risk and those aged 35 years or older or who attended five or more prenatal care visits were at lower risk of smoking during pregnancy as compared to mothers from São Luís. Smoking by the companion reduced the difference between smoking rates in the two cities by 10%. The socioeconomic variables in the model did not explain the higher prevalence of smoking during pregnancy in the more developed city.

Inadequate utilization of prenatal care in two Brazilian birth cohorts.

Data for two birth cohorts from two Brazilian municipalities, Ribeirão Preto in 1994 and São Luís in 1997/1998, were used to identify and compare factors associated with inadequate utilization of prenatal care and to identify factors capable of explaining the differences observed between the two cities. Prenatal care was defined as adequate or inadequate according to the recommendations of the Brazilian Ministry of Health. The chi-square test and Poisson regression were used to compare differences in the inadequacy of prenatal care utilization. The percentage of inadequacy was higher in São Luís (34.6%) than in Ribeirão Preto (16.9%). Practically the same variables were associated with inadequacy in both cities. Puerperae with lower educational level, without a companion or cohabiting, who delivered in public health units, younger than 20 years, multiparae and smokers, with low family income presented higher percentages of inadequate prenatal care utilization. However, the effects of some variables differed between the two cities. The risk for inadequate use of prenatal care was higher for women attended in the public health sector in São Luís and for cohabiting women in Ribeirão Preto. The effect of the remaining factors studied did not differ between cities. The category of admission accounted for 57.0% of the difference in the inadequate use of prenatal care between cities and marital status accounted for 45.3% of the difference. Even after adjustment for all variables, part of the difference in the inadequacy of prenatal care utilization remained unexplained.

Why are the rates of cesarean section in Brazil higher in more developed cities than in less developed ones?

The objective of the present study was to investigate factors associated with cesarean sections in two cities located in different regions of Brazil and to determine factors that explain the higher cesarean section rate in the more developed city, Ribeirão Preto, compared to the less developed one, São Luís. Data from two cohort studies comprising 2846 women in Ribeirão Preto in 1994, and 2443 women in São Luís in 1997/1998 were used. Adjusted and non-adjusted risk estimates were calculated using a Poisson regression model. The cesarean section rate was 33.7% in São Luís and 50.8% in Ribeirão Preto. Adjusted analysis in a joint sequential model revealed a 51% higher risk of cesarean section in Ribeirão Preto compared to São Luís (prevalence rate ratio (PRR) = 1.51). Adjustment for category of hospital admission reduced the PRR to 1.09, i.e., this variable explained 82% of the difference in the cesarean section rate between the two cities. Adjustment for the variable "the same physician for prenatal care and delivery" reduced the PRR to 1.07, with the "physician" factor explaining 86% of the difference between rates. When simultaneously adjusted for the two variables, the PRR decreased to 1.05, with these two variables explaining 90% of the difference in the cesarean section rate between the two cities, and the difference was no longer significant. The difference in the cesarean section rate between the two Brazilian cities, one more and one less developed, was mainly explained by the physician factor and, to a lesser extent, by the category of hospital admission.

[Evaluation of data quality from the information system on live births in 1997-1998]. / Avaliação da qualidade dos dados do Sistema de Informações sobre Nascidos Vivos em 1997-1998.

OBJECTIVE: To verify the concordance between data routinely collected by the Sinasc (Information System on Live Births) and data obtained by a cross-sectional survey (gold standard). METHODS: The survey was performed in a sample of 2,831 hospital deliveries in ten maternity hospitals of the municipality of São Luís, Brazil. The sample frame represented about 98% of hospital births. Sinasc's data was compared with the survey data using a computerized linkage program. Sinasc's hospital births coverage, percentage of missing or unrecorded data and consistency between Sinasc 's and the survey's data were analyzed. Concordance was measured using the kappa indicator for qualitative variables and the intraclass correlation coefficient for quantitative variables. RESULTS: The estimated Sinasc coverage was 75.8% (95% CI: 73.3%-78.2%). Five Sinasc's data fields showed good reliability: birth weight, newborn sex, hospital of birth, type of delivery and maternal age. Low birth weight rates estimated by the two data sources were similar and the concordance was high (kappa=0.94). However, preterm birth rates were higher in the survey (11.2%) than according to Sinasc 's data (1.7%) and the concordance was low (kappa=0.09). CONCLUSIONS: Estimated Sinasc coverage was low. Low birth weight rates from Sinasc's data seem to be valid and reliable. Preterm birth rates from Sinasc's data are underestimated.

Perinatal health and mother-child health care in the municipality of São Luís, Maranhão State, Brazil.

The purpose of this article was to evaluate socioeconomic and demographic indicators, reproductive health, use of prenatal, childbirth, and neonatal services, and anthropometric data for mothers and infants. The authors performed a cross-sectional analysis of a systematic sample of 2,831 hospital births in São Luís, Maranhão State, from March 1997 to February 1998 at ten public and private maternity hospitals. The sample was stratified proportionally according to the number of births in each maternity hospital. Mothers answered a standard questionnaire. Of the total, 97.9% were live births and 98% were singletons. Prenatal coverage was 89.5%, and prevalence of cesarean sections was 33.8%. A physician provided prenatal care in 75.7% of cases and performed 73.8% of the deliveries. The Unified Health System covered the costs of 76.4% of the prenatal visits and 89.7% of the deliveries. A pediatrician was present in the delivery room in 50.2% of cases. The low birth weight rate was 9.6% and the preterm birth rate 13.9%. Reasons for concern included a high percentage of adolescent mothers, single mothers (or without partners), the high cesarean rate, and the high percentage of births attended by unqualified personnel.

[Neonatal mortality trends in São Luís, Maranhão, Brazil, from 1979 to 1996]. / Tendências da mortalidade neonatal em São Luís, Maranhão, Brasil, de 1979 a 1996.

This study examined neonatal mortality trends in São Luís in the last 18 years. The early and late components were assessed and causes were classified according to SEADE Foundation criteria based on reducibility of deaths and timing of prevention (during prenatal care, childbirth, or neonatal care). Data were derived from official live birth and death records. We detected an unexpected increase in the neonatal mortality rate, due primarily to a steep rise in early neonatal deaths. Causes reducible by early diagnosis and treatment (other specific infections and other neonatal respiratory causes) and those partially reducible by adequate monitoring of pregnancy (preterm births, low birth weight, and respiratory distress syndrome) showed the largest increase. Conversely, the post-neonatal mortality rate fell. The infant mortality rate remained the same, reflecting these antagonistic trends. The important rise in the neonatal mortality rate from 1995 onwards suggests a deterioration in the quality of obstetric and neonatal services. The high cesarean rate and overcrowded neonatal services (i.e., unable to cope with increasing demands foe specialized neonatal care) indicate the urgent need for restructuring the mother and child health care system.

[Hemoglobin H: laboratory identification]. / Hemoglobina H: identificação laboratorial.

Hemoglobin H (Hb H) disease is an alpha thalassemia form characterized by low synthesis of alpha chain and high beta chain concentration; this unbalance induces the beta chain tetramers formation. Hb H is relatively frequent in Thailand and Greece. Isolated cases have been reported in Chinese, Filipinos, Malaysians. In the Near East occasional cases were observed in Greek Cypriots and Jordanian Arabs. Hb H carriers were found in Italy, Spain, Canada, Indonesia and other countries. In Brazil there are descendants of Italians, Chinese and people of negro origin who are carriers of Hb H. We identified the Hb H by electrophoresis, instability and characteristic inclusion bodies.

Hemoglobina E alfa-2 beta-2(26) glutamico-lisina (Hb E alfa-2 beta-2(26). Glu-Lis). / Hemoglobin E alpha2 beta2(26) glutamic-lysine (Hb E alpha2 beta2(26) Glu leads to Lys)

Descrevemos uma familia brasileira de ascendencia indiana, com Hb E. Esta paciente tem um dos avos paternos natural da India e os avos maternos originarios da Escandinavia, Suecia. A identificacao desta hemoglobina permitiu elucidar a origem racial. A Hb E, que tem a mesma mobilidade da Hb C e O em pH alcalino, foi diferenciada desta pela eletroforese em agar pH 6,2, segundo Robbinson onde a Hb E tem mobilidade similar a da Hb A1. O estudo do "Fingerprinting" demonstrou tratar-se da Hb E alfa-2 beta-2(26) Glu-Lys, como foi descrita por Hunt & col. e Frischer & col. Os dois casos estudados nao apresentavam anemia e os pacientes levam vida normal