RESUMO
Birth defects (BDs) are structural or functional anomalies, sporadic or hereditary, of prenatal origin. Public health surveillance is defined as the ongoing systematic collection, analysis, and interpretation of outcome-specific data for use in the planning, implementation, and evaluation of public health practice. BD surveillance systems may have different characteristics according to design, coverage, type of surveillance, case ascertainment, case definition, BD description, maximum age of diagnosis, pregnancy outcomes, coding systems, and the location of the coding process (central or local). The aim of this article is to describe and compare methodology, applications, and results of birth defect surveillance systems in two South-American countries: Colombia and Argentina. In both countries, the surveillance systems developed activities in relation to the Zika virus emergency. For most BDs, a statistically significant higher prevalence is observed in Argentina-RENAC than in Colombian registries. This may be due to methodological reasons or real differences in prevalence. The strengths, weaknesses, and the future perspectives of the Argentine and Colombian systems are presented. When developing a surveillance system, the objectives, the available resources, and previous experiences in similar contexts must be taken into account. In that sense, the experience of Argentina and Colombia can be useful for others when developing a birth defect surveillance system.
RESUMO
To further exploit yeast as a model for cellular aging we have modified the replicative life span assay to force respiration, by replacing glucose with the non-fermentable carbon source glycerol. The growth rates of several different strains varied greatly, with doubling times ranging from 2.7 to 7 h. Life spans of all strains were lower on media containing glycerol than on media containing glucose. However, supplementation of glycerol-containing media with copper resulted in increases in life span of between 17 and 72%; life spans equivalent to or beyond those obtained on glucose media. Addition of copper to glucose medium had no effect on life span. Microarray analysis showed that genes responsible for high affinity import of copper display reduced expression upon addition of copper, while most genes showed no change in expression. No differences in growth rate, oxygen uptake, or the levels of subunit II of the copper-containing cytochrome c oxidase were found between cultures of yeast grown with or without copper supplementation. Copper supplementation greatly extended the life span of sod1 and sod2 strains, suggesting that addition of copper may reduce the generation of superoxide. Forcing yeast to respire places an emphasis on mitochondrial function and may aid in the identification of factors involved in aging in other respiratory-dependent organisms.
Assuntos
Cobre/farmacologia , Mitocôndrias/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/fisiologia , Antiporters/genética , Antiporters/metabolismo , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Proliferação de Células , Transportador de Cobre 1 , Meios de Cultura/farmacologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Regulação Fúngica da Expressão Gênica , Glucose/metabolismo , Glicerol/metabolismo , Mutação , Oxigênio/metabolismo , Regiões Promotoras Genéticas , Proteínas SLC31 , Saccharomyces cerevisiae/citologia , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismoRESUMO
We have previously shown that copper supplementation extends the replicative life span of Saccharomyces cerevisiae when grown under conditions forcing cells to respire. We now show that copper's effect on life span is through Fet3p, a copper containing enzyme responsible for high affinity transport of iron into yeast cells. Life span extensions can also be obtained by supplementing the growth medium with 1mM ferric chloride. Extension by high iron levels is still dependent on the presence of Fet3p. Life span extension by iron or copper requires growth on media containing glycerol as the sole carbon source, which forces yeast to respire. Yeast grown on glucose containing media supplemented with iron show no extension of life span. The iron associated with cells grown in media supplemented with copper or iron is 1.4-1.8 times that of cells grown without copper or iron supplementation. As with copper supplementation, iron supplementation partially rescues the life span of superoxide dismutase mutants. Cells grown with copper supplementation display decreased production of superoxide as measured by dihydroethidium staining.