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N A Rosario

Publications and source records attributed to N A Rosario.

16 recordsLinked to original sources
PubMed1999

Geographic heterogeneity of 4 common worldwide cystic fibrosis non-DF508 mutations in Brazil.

Cystic fibrosis (CF) is an autosomal recessive disease caused by at least 750 different mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The frequency of the most common mutation (DF508) in Brazilian patients of European origin is 47%. To determine the frequency of 4 other common CF mutations (G542X, G551D, R553X, and N1303K) in Brazilian patients of European origin, we used direct polymerase chain reaction (PCR) amplification of DNA obtained from dried blood spots on Guthrie cards. The DNA came from 247 non-DF508 chromosomes from 172 Brazilian CF patients ascertained from 5 different states of Brazil. The results show that the 4 mutations account for 17% of the non-DF508 alleles and only 9% of the total number of Brazilian CF alleles. Overall, the frequency of each mutation is different from northern European and North American populations but similar to southern European populations, mainly the Italian and Spanish populations. When Brazilian patients of European origin are grouped according to state of birth, the frequencies of the mutations are significantly different between southern and southeastern states of Brazil. Therefore there are serious implication for risk assessment of DNA-based tests in heterogeneous populations such as Brazilians. Further studies are needed to identify the remaining 44% of CF mutations for the different populations and regions of Brazil.

Adolescent↗
PubMed1997

Regional distribution of cystic fibrosis-linked DNA haplotypes in Brazil: multicenter study.

The restriction fragment length polymorphism (RFLP) haplotypes of cystic fibrosis (CF) alleles vary between populations. To determine the distribution of two RFLPs (XV-2C and KM-19) that are tightly linked to the CF locus, we analyzed a white sample from five different states of Brazil. The haplotypes of 314 CF- and 237 non-CF-bearing chromosomes were uniformly distributed over the five states. The XV-2C allele and haplotype frequencies and the degree of linkage disequilibrium were determined. These were similar to values previously reported in southern European countries but different from results reported for northern and central Europe and North America. In contrast, although KM-19 allele frequencies differed between Brazilian states and European and North American countries, these frequencies were similar to values reported in black Americans. A significant proportion of Brazilian CF-bearing chromosomes had less common haplotypes, suggesting a heterogeneous distribution of CF gene mutations among Brazilians. Further studies are needed to identify the mutations affecting the Brazilian CF patients with various haplotypes.

Adolescent↗
PubMed1997

Cystic fibrosis in the Brazilian population: DF508 mutation and KM-19/XV-2C haplotype distribution.

We have used PCR amplification of DNA obtained from Guthrie cards to identify the DF508 mutation and correlate it with the allele frequencies at two polymorphic loci (XV-2C and KM-19) closely linked to the cystic fibrosis gene. The DNA came from 193 white Brazilian families affected by cystic fibrosis and living in five different states of Brazil. The distribution of the haplotypes derived from the DF508 and non-DF508 XV-2C/KM-19 genotypes indicates that 88% of the DF508 alleles are linked to haplotype B and suggests that high heterogeneity exists among the non-DF508 cystic fibrosis alleles occurring in different states. Our data can be used to compare linkage disequilibrium between Brazilians and other heterogeneous populations where the DF508 mutation frequency is low and where many different rare mutations account for the remaining recessive cystic fibrosis alleles.

Adolescent↗
PubMed1993

Evaluation of complement activation in premature newborn infants with hyaline membrane disease.

Fifteen premature newborns with hyaline membrane disease causing acute respiratory distress were evaluated for complement activation. A high intrapulmonary right-to-left shunt and marked arterial-alveolar oxygen difference indicated the severity of the respiratory failure. Twenty preterm healthy infants served as controls. Total haemolytic activity, plasma concentrations of complement components and regulatory proteins (C3, C4, C1-inhibitor, factors H and I) as well as activation products (C3a, C3dg, C1rsC1-inhibitor, C3b(Bb)P) gave no evidence of significant complement activation. Functional activity of the ubiquitous regulatory protein C1-inhibitor was significantly reduced without impact on classical pathway activation. These data suggest that, in contrast to the adult form of respiratory distress syndrome, the low-pressure pulmonary oedema characterising hyaline membrane disease is not mediated by activation of the complement system.

Biomarkers↗
PubMed1981

Skin test sensitivity to Acacia pollen in Brazil.

A total of 36 patients with asthma and/or rhinitis were evaluated for the presence of allergy skin sensitivity to Acacia pollen in Brazil (eastern and southern regions). Only four patients showed mild intradermal skin test reactions to Acacia pollen extract (1,000 PNU/ml). Despite being largely distributed in those regions, Acacia pollen is not an important allergen involved in the pathogenesis of respiratory atopy in Brazil.

Adolescent↗
PubMed1976

Comparison of the allergenic properties of bee venom and whole bee body extract.

The allergenic properties of bee venom and whole bee body extract were compared by in vivo and in vitro tests. The majority of patients with known bee sting sensitivity had positive intracutaneous skin test reactions with bee venom and had bee venom specific IgE in their sera. Of seventeen patients with ppsitive bee venom skin tests, nine had positive tests with whole bee body extract. Of thirty sera containing elevated levels of bee venom specific IgE obtained from untreated patients, fourteen sera contained whole body specific IgE but in much lower titres. In RAST inhibition experiments using both bee venom and whole bee body extract as coupling antigens, bee venom was a more potent inhibiting antigen than whole body extract. From these experiments we conclude that bee venom is a more potent allergen than whole bee body extract.

Animals↗
PubMedDate not supplied

Comparison of terfenadine once daily with terfenadine twice daily for the treatment of perennial allergic rhinitis.

In a double-blind, parallel-group study to compare the efficacy of 120 mg terfenadine taken orally once daily with that of the conventional regimen of 60 mg terfenadine taken twice daily, 30 patients with perennial allergic rhinitis were enrolled. Groups of 15 patients were treated for 7 days with either 60 mg terfenadine twice daily, morning and evening, or 120 mg terfenadine once daily in the morning and placebo in the evening. The physician detected marked to total relief of symptoms (sneezing, rhinorrhoea, nasal pruritus and nasal obstruction) at similar rates (60% and 66%) in the two groups and patients in both groups reported a reduction in symptoms. The incidence of reported side-effects (sedation and mild headache) was low and not significantly different using either regimen. The results indicate that the new once-daily regimen of terfenadine was as effective and as well tolerated as the twice-daily regimen for the treatment of perennial allergic rhinitis.

Administration, Oral↗
PubMedDate not supplied

[Sensitization to the acarus Blomia tropicalis in patients with respiratory allergy].

House dust mites are important environmental allergens in Southern Brazil. Some allergic patients do not respond to specific immunotherapy for Dermatophagoides ssp. For that reason we decided to evaluate the skin test sensitivity to tropical mites, Blomia tropicalis and Blomia kulagini. Patients with perennial allergic rhinitis and/or asthma were selected for tests. (N = 135). The wheals cross diameter were recorded. The frequency of strong reactions were 82% for B. tropicalis, 69% for D. pteronyssinus, 56% for D. farinae and 46% for B. kulagini. Wheals were larger with Dermatophagoides sp in 30 patients (22%); similar in 61 patients (45%) and larger with-Blomia sp in 44 patients (33%). Three patients reacted only to Blomia. This study verifies that sensitization to Blomia is common in patients with respiratory allergy. In addition it contains unique allergens that could account for treatment failures with Dermatophagoides in some cases.

Acari↗
PubMedDate not supplied

Quantitative skin prick tests and serum IgE antibodies in atopic asthmatics.

We assessed the immediate skin reactivity to Dermatophagoides pteronyssinus in children with atopic asthma in order to determine the intensity of the skin reaction, its time course and the end-point allergen concentration. We also examined the correlation between the total and D. pteronyssinus-specific IgE levels and the severity of asthma. Asthmatic children were age- and sex matched to nonatopic children. Significant eosinophilia and elevated serum IgE levels were correlated with the presence of asthma but bore no relation to the severity of the disease. The average end-point allergen concentration was approximately 50 allergy units (AU). The mean wheal diameter ranged from 6.1 mm in mild asthmatics to 7.1 mm in severe cases; this difference, however, was not significant. Most of the patients (85%) reported local pruritus within 120 seconds after allergen injection. The time lag until the start of the reaction and the wheal diameters were correlated with the levels of D. pteronyssinus-specific serum IgE antibodies, and with the end-point allergen concentration. These two variables therefore provide good indicators of the time course and the extent of the skin test reaction in individuals sensitive to the allergen tested.

Adolescent↗