Functional consequences of inhibition of nucleotide breakdown in rat vas deferens: a study with Evans blue

The effect of Evans blue on nucleotide breakdown, nucleotide-evoked contractions and electrically evoked contractions, overflow of ATP and overflow of tritium (after labelling with [³H]-noradrenaline) was studied in rat vas deferens. Pieces of vas deferens degraded 83 to 85% of added ATP, ADP and 2-methylthio ATP (all 100 M) over 30 min. Evans blue (100 M) reduced this degradation to 22 to 26%. Nucleotides elicited contraction with potency declining in the order , \-methylene ATP > 2-methylthio ATP > ATP > ADP. Evans blue (100 M) shifted the concentration-response curve of , \-methylene ATP to the right and increased the maximum. Concentration-response curves of ATP, ADP and 2-methylthio ATP, in contrast, were shifted to the left and responses were much potentiated. In the presence of Evans blue, the rank order of potency was ATP > 2-methylthio ATP > , \-methylene ATP > ADP. Electrical field stimulation (100 pulses at 10 Hz) elicited contraction and an overflow of tritium and ATP. Evans blue (100 M) did not alter the contraction and the evoked overflow of tritium but increased 24-fold the evoked overflow of ATP. The results indicate that Evans blue may serve as an — albeit impure — ecto-nucleotidase inhibitor in functional experiments. Such experiments demonstrate that the low potency of ATP (and also ADP and 2-methylthio ATP) in eliciting contraction, and the small size of the overflow of ATP upon sympathetic nerve stimulation, are due to rapid breakdown.     

Prevalence of hypovitaminosis a in children of peripheral districts of Campinas São Paulo, Brazil

The prevalence of hypovitaminosis A among children of the peripheral districts of the city of Campinas, S o Paulo, Brazil, was estimated by determining serum retinol levels by High Performance Liquid Chromatography (HPLC) in a sample of 131 children aged between three and ten years, between April 1991 and February 1992. A prevalence of 17.6% and retinol concentrations in the range of 0.35 to 0.70 micromol/L were found (CI=11.1-24.1; 95%), indicating the existence of public health risk Ophthalmological examinations, however, failed to detect any cases of xerophthalmy. Additional characterization of the sample was obtained from 341 children. The per capita income of the average household was surprisingly high for low-income areas. According to FAO-WHO standards, food consumption was adequate only for protein (133.96%). Adequacy levels were low for energy (87.76%) and particularly for vitamin A (66.13%) and iron (42.14%). Height for-age and weight-for-height anthropometric indices revealed that many children were located below -1 standard deviation.     

Surfactant replacement therapy: a multicentric trial comparing two dosage approaches

This is an interim analysis of a multicentric trial that took place in 7 Neonatal Units to compare two initial doses of exigenous pulmonary surfactant (100 mg/kg and 200 mg/kg of phospholipids)by using a porcine surfactant for the treatment of very severe Hyaline Membrane Disease. The initial higher dose produced better oxigenation of arterial blood, reducing the time in high oxygen concentrations,while retreatments were necessary in less than half of the infants receiving 200 mg/kg as initial dose. The protocol of this study allowed the administration of additional doses only when FiO(2) was equal or greater than 0.40 instead of > 0.21, as in a large study recently published, where the same initial doses were given. This resulted in more than 40% reduction in the amount of surfactant administered,with apparently similar clinical outcome.     

Xanthogranulomatous pyelonephritis

A four years-old boy with Xanthogranulomatous pyelonephritis was surgically treated at the Pediatric Surgery Unit of the Santa Casa de Misericórdia of Maceió. Comments are made upon pathology, pre-operative diagnostic difficulties, differential diagnosis, and the rare occurrence in children.     

Measles seroprevalence among pediatricians in a teaching hospital]

OBJECTIVE: A measles outbreak occurred in S. Paulo state, during 1996 and 1997, resulting in 20,921 cases. Forty seven percent of the cases occurred in people between 20 and 29 years of age, and one of the control strategies of the Department of Health was the vaccination of health care workers. The prevalence of antibodies against measles among the hospital pediatricians was investigated. METHODS: One hundred and fifty samples were taken from volunteer pediatricians to test for measles antibodies using ELISA. A questionnaire about their having had measles and the vaccine was filled out. RESULTS: Of the 150 doctors, 122 (81.4%) were female and 28 (18.6%) male, of between 23 and 46 years of age (mean and median 27 years). The majority (98%-147/150) had protective levels of antibodies against measles (>100 UI/ml); 118 (80.3%-118/147) without and 29 (19.7%-29/147) with a history of measles. Only 3 pediatricians (2%-3/150), had negative serology, 2 without and 1 with a history of measles. Out of the 118 without history of measles, 79 (67%-39/118) in spite of the protective level of antibodies against measles, did not know if they, had been vaccinated. Out of the 79 vaccinated pediatricians, 64 (81%-64/79), had been vaccinated 25 years before, and still maintained protective levels of antibodies. Of the 3 doctors with negative serologies only one declared that he had been vaccinated. CONCLUSIONS: Measles seroprevalence among pediatricians of this hospital is high, especially due to preceding vaccination. On the other hand, the 2% of pediatricians with negative serology, in an epidemic situation could constitute a significant population for the acquisition and dissemination of the disease.     

Validity of information on occupation and principal cause on death certificates in Botucatu, Sao Paulo

The aim of this paper was to evaluate the accuracy of data on death certificates for occupation and main cause of death. Measure of agreement was assessed comparing data from death certificates with those from both medical records and next-of-kin interviews, analyzing information for 552 residents of Botucatu, Southeast Brazil, who died in 1997. Kappa coefficients of 0.31 (95% C.I. 0. 29-0.34) and 0.76 (95% C.I. 0.75-0.76) were obtained for data on occupation and main cause of death, coded by a Brazilian two-digit classification and the three-digit ICD-10 classification, respectively. One can conclude that, although quality of the main cause of death is acceptable for pilot studies, data on occupation taken only from death certificates is not accurate enough to be used in epidemiological research.     

Tuberculosis treatment adherence in Pelotas, Brazil, from the patient's perspective

This study deals with adherence to tuberculosis treatment among men and women as well as the disease's links and consequences vis-à-vis life styles and treatment outcomes. The ethnographic study was a component of the Tuberculosis Epidemiological Control Project in the city of Pelotas and aimed to identify the reasons patients failed to complete treatment. Direct ethnographic observations and semi-structured interviews were used. Use of the term "adherence" is justified by the concern for extending to other fundamental factors in addition to the patient's own individual responsibility. This approach fostered an understanding of views towards disease, social dynamics among the various protagonists involved in the disease process, and treatment. Some of the factors considered in adherence to treatment were: socio-demographic characteristics, cultural factors, popular beliefs, the cost-benefit relationship, physical and chemical aspects of the drugs, the physician-patient relationship, and level of family participation in treatment.     

Thalidomide in Brazil: monitoring with shared responsibility?

This paper discusses issues related to the regulation and rational use of thalidomide in Brazil, by means of a historical approach comprising three different stages. The first part is a historical review of the controversial drug since it was first synthesized, then marketed and subsequently banned during the 1950s and 60s, until the present, when an apparently irreversible process of rehabilitating the drug is under way. Brazilian experience with the use of thalidomide is described, emphasizing legal, political, and institutional work led by two social movements, the Brazilian Association of People with Thalidomide Syndrome (ABPST) and the Movement for Reintegration of People with Hansen's Disease (Morhan). The article describes the results and analyzes an active search of new cases in what is a second generation of thalidomide syndrome in Brazil. Finally, based on clinical and scientific evidence of thalidomide's therapeutic efficacy, the growth of social movements struggling both for and against authorization of the drug, and a restrictive regulation proposed by the Ministry of Health, the article discusses the implementation of policies for the regulation and rational use of thalidomide in Brazil.