Showing papers by "Oswaldo Cruz Foundation published in 2008"

Cancer survival in five continents: a worldwide population-based study (CONCORD)

Abstract: Summary Background Cancer survival varies widely between countries. The CONCORD study provides survival estimates for 1·9 million adults (aged 15–99 years) diagnosed with a first, primary, invasive cancer of the breast (women), colon, rectum, or prostate during 1990–94 and followed up to 1999, by use of individual tumour records from 101 population-based cancer registries in 31 countries on five continents. This is, to our knowledge, the first worldwide analysis of cancer survival, with standard quality-control procedures and identical analytic methods for all datasets. Methods To compensate for wide international differences in general population (background) mortality by age, sex, country, region, calendar period, and (in the USA) ethnic origin, we estimated relative survival, the ratio of survival noted in the patients with cancer, and the survival that would have been expected had they been subject only to the background mortality rates. 2800 life tables were constructed. Survival estimates were also adjusted for differences in the age structure of populations of patients with cancer. Findings Global variation in cancer survival was very wide. 5-year relative survival for breast, colorectal, and prostate cancer was generally higher in North America, Australia, Japan, and northern, western, and southern Europe, and lower in Algeria, Brazil, and eastern Europe. CONCORD has provided the first opportunity to estimate cancer survival in 11 states in USA covered by the National Program of Cancer Registries (NPCR), and the study covers 42% of the US population, four-fold more than previously available. Cancer survival in black men and women was systematically and substantially lower than in white men and women in all 16 states and six metropolitan areas included. Relative survival for all ethnicities combined was 2–4% lower in states covered by NPCR than in areas covered by the Surveillance Epidemiology and End Results (SEER) Program. Age-standardised relative survival by use of the appropriate race-specific and state-specific life tables was up to 2% lower for breast cancer and up to 5% lower for prostate cancer than with the census-derived national life tables used by the SEER Program. These differences in population coverage and analytical method have both contributed to the survival deficit noted between Europe and the USA, from which only SEER data have been available until now. Interpretation Until now, direct comparisons of cancer survival between high-income and low-income countries have not generally been available. The information provided here might therefore be a useful stimulus for change. The findings should eventually facilitate joint assessment of international trends in incidence, survival, and mortality as indicators of cancer control. Funding Centers for Disease Control and Prevention (Atlanta, GA, USA), Department of Health (London, UK), Cancer Research UK (London, UK).

Impact of environment and social gradient on Leptospira infection in urban slums.

Abstract: Background Leptospirosis has become an urban health problem as slum settlements have expanded worldwide. Efforts to identify interventions for urban leptospirosis have been hampered by the lack of population-based information on Leptospira transmission determinants. The aim of the study was to estimate the prevalence of Leptospira infection and identify risk factors for infection in the urban slum setting.

Cross-cultural adaptation of the Independence in Activities of Daily Living Index (Katz Index)

Abstract: Desenvolvimento e analise do desempenho de uma adaptacao transcultural para o portugues da Escala de Katz de independencia em atividades da vida diaria. Duas traducoes e duas retrotraducoes analisaram as equivalencias conceitual, de itens e semântica para a escolha da versao final. A equivalencia operacional foi avaliada em um estudo piloto, testando-se a confiabilidade e a consistencia interna da versao adaptada por meio de reteste no mesmo dia em 156 pacientes ou apos sete dias da primeira entrevista. A resolucao de diferencas sutis em alguns itens levou a equivalencia cultural. A versao final foi considerada facil de se entender e de aplicar. A concordância corrigida para o acaso (kappa ponderado) foi de 0,91. O alfa de Chronbach variou de 0,80 a 0,92. A versao em portugues da Escala de Katz de independencia em atividades da vida diaria, completamente desenvolvida e testada, provou ser equivalente a original em ingles. Os itens apresentaram consistencia interna e as taxa foram confiaveis.

Multiplex cytokine profile from dengue patients: MIP-1beta and IFN-gamma as predictive factors for severity

Abstract: Dengue virus pathogenesis is not yet fully understood and the identification of patients at high risk for developing severe disease forms is still a great challenge in dengue patient care. During the present study, we evaluated prospectively the potential of cytokines present in plasma from patients with dengue in stratifying disease severity. Seventeen-cytokine multiplex fluorescent microbead immunoassay was used for the simultaneous detection in 59 dengue patients. GLM models using bimodal or Gaussian family were determined in order to associate cytokines with clinical manifestations and laboratory diagnosis. IL-1β, IFN-γ, IL-4, IL-6, IL-13, IL-7 and GM-CSF were significantly increased in patients with severe clinical manifestations (severe dengue) when compared to mild disease forms (mild dengue). In contrast, increased MIP-1β levels were observed in patients with mild dengue. MIP-1β was also associated with CD56+NK cell circulating rates. IL-1β, IL-8, TNF-α and MCP-1 were associated with marked thrombocytopenia. Increased MCP-1 and GM-CSF levels correlated with hypotension. Moreover, MIP-1β and IFN-γ were independently associated with both dengue severity and disease outcome. Our data demonstrated that the use of a multiple cytokine assay platform was suitable for identifying distinct cytokine profiles associated with the dengue clinical manifestations and severity. MIP-β is indicated for the first time as a good prognostic marker in contrast to IFN-γ that was associated with disease severity.

P2X7 receptor-Pannexin1 complex: pharmacology and signaling

Abstract: Pannexin 1 (Panx1), an ortholog to invertebrate innexin gap junctions, has recently been proposed to be the pore induced by P2X7 receptor (P2X7R) activation. We explored the pharmacological action of compounds known to block gap junctions on Panx1 channels activated by the P2X7R and the mechanisms involved in the interaction between these two proteins. Whole cell recordings revealed distinct P2X7R and Panx1 currents in response to agonists. Activation of Panx1 currents following P2X7R stimulation or by membrane depolarization was blocked by Panx1 small-interfering RNA (siRNA) and with mefloquine > carbenoxolone > flufenamic acid. Incubation of cells with KN-62, a P2X7R antagonist, prevented current activation by 2′(3′)-O-(4-benzoylbenzoyl)adenosine 5′-triphosphate (BzATP). Membrane permeabilization to dye induced by BzATP was also prevented by Panx1 siRNA and by carbenoxolone and mefloquine. Membrane permeant (TAT-P2X7) peptides, provided evidence that the Src homology 3 death domain of the COOH-terminus ...

Vesicular transport in Histoplasma capsulatum: an effective mechanism for trans-cell wall transfer of proteins and lipids in ascomycetes

Abstract: Vesicular secretion of macromolecules has recently been described in the basidiomycete Cryptococcus neoformans, raising the question as to whether ascomycetes similarly utilize vesicles for transport. In the present study, we examine whether the clinically important ascomycete Histoplasma capsulatum produce vesicles and utilized these structures to secrete macromolecules. Transmission electron microscopy (TEM) shows transcellular secretion of vesicles by yeast cells. Proteomic and lipidomic analyses of vesicles isolated from culture supernatants reveal a rich collection of macromolecules involved in diverse processes, including metabolism, cell recycling, signalling and virulence. The results demonstrate that H. capsulatum can utilize a trans-cell wall vesicular transport secretory mechanism to promote virulence. Additionally, TEM of supernatants collected from Candida albicans, Candida parapsilosis, Sporothrix schenckii and Saccharomyces cerevisiae documents that vesicles are similarly produced by additional ascomycetes. The vesicles from H. capsulatum react with immune serum from patients with histoplasmosis, providing an association of the vesicular products with pathogenesis. The findings support the proposal that vesicular secretion is a general mechanism in fungi for the transport of macromolecules related to virulence and that this process could be a target for novel therapeutics.

Leishmaniasis treatment—a challenge that remains: a review

Abstract: Leishmaniasis is a disease caused by flagellate protozoan Leishmania spp. and represents an emergent illness with high morbidity and mortality in the tropics and subtropics. Since the discovery of the first drugs for Leishmaniasis treatment (i.e., pentavalent antimonials), until the current days, the search for substances with antileishmanial activity, without toxic effects, and able to overcome the emergence of drug resistant strains still remains as the current goal. This article reports the development of new chemotherapies through the rational design of new drugs, the use of products derived from microorganisms and plants, and treatments related to immunity as new alternatives for the chemotherapy of leishmaniasis.

Adherence to antiretroviral therapy for human immunodeficiency virus/acquired immune deficiency syndrome among drug users: a systematic review

Abstract: Aims Adherence to highly active antiretroviral therapy (HAART) is a key predictor of survival for human immunodeficiency virus (HIV)-infected people. Suboptimal adherence among marginalized populations such as HIV-positive drug users could be associated with clinical failure and the emergence of viral resistance. Objective To conduct a systematic review of studies assessing adherence to HAART among HIV-positive drug users (DU) and identify factors associated with non-adherence to HIV treatment. Data sources Seven electronic databases were searched for peerreviewed papers published in English, French, Spanish or Portuguese, from 1996 to 2007. Study selection and data abstraction Studies were excluded if they presented only qualitative data, were reviews themselves or assessed other populations without disaggregating data on DU. Findings on adherence were extracted and summarized. Data synthesis Forty-one studies were considered, which studied a total of 15 194 patients, the majority of whom were HIV-positive DU (n = 11 628, 76.5%). Twenty-two studies assessed adherence using patient self-reports, eight used pharmacy records, three used electronic monitoring [i.e. Medication Event Monitoring Systems (MEMS) caps], six studies used a combination of patient self-report, clinical data and MEMS-caps, and two analyzed secondary data. Overall, active substance use was associated with poor adherence, as well as depression and low social support. Higher adherence was found in patents receiving care in structured settings (e.g. directly observed therapy) and/or drug addiction treatment (especially substitution therapy). Conclusion While lower than other populations—especially among users of stimulants, incarcerated DU and patients with psychiatric comorbidities—adherence to HAART among HIV-positive DU can be achieved. Better adherence was identified among those engaged in comprehensive services providing HIV and addiction treatment with psychosocial support.

Out of South America: multiple origins of non-native apple snails in Asia

Abstract: Apple snails (Ampullariidae: Pomacea ) native to the New World have become agricultural and environmental pests widely in southern and eastern Asia since their introduction in about 1980. Although their impacts have been extensively documented, considerable confusion persists regarding their identities and geographical origins. Efforts to resolve the confusion have suffered from inadequate taxonomic and geographical sampling from both native and introduced ranges. Using phylogenetic and genealogical methods, we analysed 610–655 bp of cytochrome c oxidase subunit I DNA sequences from 783 apple snails from 164 Asian locations and 57 native South American locations. In Asia, we found four species of Pomacea in two clades: (1) Pomacea canaliculata and P. insularum , and (2) P. scalaris and P. diffusa . Parsimony networks and mismatch distributions indicate that the non-native ranges of the two most widespread species, P. canaliculata and P. insularum , probably result from multiple introductions. Molecular analyses are consistent with early accounts; non-native P. canaliculata populations trace back to multiple locations in Argentina and have probably been introduced more than once. In contrast, P. insularum was probably introduced from Brazil and Argentina independently. Multiple introductions may, in part, explain the success and rapid spread of these two species. Unlike P. canaliculata and P. insularum , P. scalaris and P. diffusa were probably introduced through the aquarium trade, derived originally from Argentina and Brazil, respectively. Possible physiological, ecological, and native range differences among these four species highlight the importance of accurate identification in understanding invasion patterns and processes, which is vital in developing and implementing management strategies.

Human eosinophils constitutively express multiple Th1, Th2, and immunoregulatory cytokines that are secreted rapidly and differentially

Abstract: Eosinophils are innate immune leukocytes implicated in the initiation and maintenance of type 2 immune responses, including asthma and allergy. The ability to store and rapidly secrete preformed cytokines distinguishes eosinophils from most lymphocytes, which must synthesize cytokine proteins prior to secretion and may be a factor in the apparent Th2 bias of eosinophils. Multiple studies confirm that human eosinophils from atopic or hypereosinophilic donors can secrete over 30 cytokines with a varying and often opposing immune-polarizing potential. However, it remains unclear whether all of these cytokines are constitutively preformed and available for rapid secretion from eosinophils in the circulation of healthy individuals or are restricted to eosinophils from atopic donors. Likewise, the relative concentrations of cytokines stored within eosinophils have not been studied. Here, we demonstrate that human blood eosinophils are not singularly outfitted with Th2-associated cytokines but rather, constitutively store a cache of cytokines with nominal Th1, Th2, and regulatory capacities, including IL-4, IL-13, IL-6, IL-10, IL-12, IFN-γ, and TNF-α. We demonstrate further rapid and differential release of each cytokine in response to specific stimuli. As agonists, strong Th1 and inflammatory cytokines elicited release of Th2-promoting IL-4 but not Th1-inducing IL-12. Moreover, a large quantity of IFN-γ was secreted in response to Th1, Th2, and inflammatory stimuli. Delineations of the multifarious nature of preformed eosinophil cytokines and the varied stimulus-dependent profiles of rapid cytokine secretion provide insights into the functions of human eosinophils in mediating inflammation and initiation of specific immunity.

Leptospirosis-associated Severe Pulmonary Hemorrhagic Syndrome, Salvador, Brazil

Abstract: We report the emergence of leptospirosis-associated severe pulmonary hemorrhagic syndrome (SPHS) in slum communities in Salvador, Brazil. Although active surveillance did not identify SPHS before 2003, 47 cases were identified from 2003 through 2005; the case-fatality rate was 74%. By 2005, SPHS caused 55% of the deaths due to leptospirosis.

Biological and socio-cultural determinants of physical activity in adolescents

Abstract: A atividade fisica e um comportamento importante na promocao de saude e na prevencao de doencas. Para que se desenvolvam programas eficazes no incentivo a pratica de atividade fisica em adolescentes, torna-se necessario que se identifiquem os fatores que a determinam. Este estudo pretende rever alguns dos aspectos do estado atual do conhecimento acerca da influencia de determinantes demografico-biologicos (idade, sexo, estatuto socio-economico) e socio-culturais (familia, pares e professor de educacao fisica) na atividade fisica de adolescentes. Nesta revisao apenas foram incluidos estudos efetuados com amostras superiores a 100 adolescentes com idades entre os 10 e os 18 anos, que tenham adotado delineamentos de pesquisa transversal e que tenham utilizado questionarios. Os principais resultados e conclusoes foram que: a idade parece estar negativamente associada a atividade fisica; o sexo masculino tende a estar mais envolvido nessas atividades; o estatuto socio-economico elevado parece ser um fator protetor do risco de inatividade fisica; a participacao da familia e dos pares em atividades fisicas parece estar positivamente associada as atividades por parte dos adolescentes; o professor de educacao fisica parece nao representar um fator propiciador da atividade fisica.

Immunity to a salivary protein of a sand fly vector protects against the fatal outcome of visceral leishmaniasis in a hamster model.

Abstract: Visceral leishmaniasis (VL) is a fatal disease for humans, and no vaccine is currently available. Sand fly salivary proteins have been associated with protection against cutaneous leishmaniasis. To test whether vector salivary proteins can protect against VL, a hamster model was developed involving intradermal inoculation in the ears of 100,000 Leishmania infantum chagasi parasites together with Lutzomyia longipalpis saliva to mimic natural transmission by sand flies. Hamsters developed classical signs of VL rapidly, culminating in a fatal outcome 5–6 months postinfection. Saliva had no effect on the course of infection in this model. Immunization with 16 DNA plasmids coding for salivary proteins of Lu. longipalpis resulted in the identification of LJM19, a novel 11-kDa protein, that protected hamsters against the fatal outcome of VL. LJM19-immunized hamsters maintained a low parasite load that correlated with an overall high IFN-γ/TGF-β ratio and inducible NOS expression in the spleen and liver up to 5 months postinfection. Importantly, a delayed-type hypersensitivity response with high expression of IFN-γ was also noted in the skin of LJM19-immunized hamsters 48 h after exposure to uninfected sand fly bites. Induction of IFN-γ at the site of bite could partly explain the protection observed in the viscera of LJM19-immunized hamsters through direct parasite killing and/or priming of anti-Leishmania immunity. We have shown that immunity to a defined salivary protein (LJM19) confers powerful protection against the fatal outcome of a parasitic disease, which reinforces the concept of using components of arthropod saliva in vaccine strategies against vector-borne diseases.

High Level of PD-1 Expression on Hepatitis C Virus (HCV)-Specific CD8+ and CD4+ T Cells during Acute HCV Infection, Irrespective of Clinical Outcome

Abstract: We monitored expression of PD-1 (a mediator of T-cell exhaustion and viral persistence) on hepatitis C virus (HCV)-specific CD8 + and CD4 + T cells from blood and liver during acute and chronic infections and after the resolved infection stage. PD-1 expression on HCV-specific T cells was high early in acute infection irrespective of clinical outcome, and most cells continued to express PD-1 in resolved and chronic stages of infection; intrahepatic expression levels were especially high. Our results suggest that an analysis of PD-1 expression alone is not sufficient to predict infection outcome or to determine T-cell functionality in HCV infection.

[Acute phase of Chagas disease in the Brazilian Amazon region: study of 233 cases from Pará, Amapá and Maranhão observed between 1988 and 2005].

Abstract: Two hundred and thirty-three cases of the acute phase of Chagas disease, from Para, Amapa and Maranhao, were observed between 1988 and 2005 One hundred and sixty were studied retrospectively from 1988 to 2002 and seventy-three were prospectively followed up from 2003 to 2005 Among the cases studied, 785% (183/233) formed part of outbreaks, probably due to oral transmission (affecting a mean of 4 individuals), and 215% (50/233) were isolated cases Cases were taken to be acute if they presented positive direct parasitological tests (fresh blood, thick drop or Quantitative Buffy Coat, QBC) and/or positive anti Trypanosoma cruzi IgM Xenodiagnosis was also performed on 224 patients and blood culturing on 213 All the patients had clinical and epidemiological evaluations The most frequent clinical manifestations were fever (100%), headache (923%), myalgia (841%), pallor (67%), dyspnea (584%), swelling of the legs (579%), facial edema (575%), abdominal pain (443%), myocarditis (399%) and exanthema (27%) The electrocardiogram showed abnormalities of ventricular repolarization in 385%, low QRS voltage in 154%, left-axis deviation in 115%, ventricular ectopic beats in 58%, bradycardia in 58%, tachycardia in 58%, right branch block in 48% and atrial fibrillation in 48% The most frequently observed abnormality on the echocardiogram was pericardial effusion, in 462% of the cases Thirteen (56%) patients died: ten (769%) of them due to cardiovascular involvement, two due to digestive complications and one due to indeterminate causes

Canine vector-borne diseases in Brazil.

Abstract: Canine vector-borne diseases (CVBDs) are highly prevalent in Brazil and represent a challenge to veterinarians and public health workers, since some diseases are of great zoonotic potential. Dogs are affected by many protozoa (e.g., Babesia vogeli, Leishmania infantum, and Trypanosoma cruzi), bacteria (e.g., Anaplasma platys and Ehrlichia canis), and helminths (e.g., Dirofilaria immitis and Dipylidium caninum) that are transmitted by a diverse range of arthropod vectors, including ticks, fleas, lice, triatomines, mosquitoes, tabanids, and phlebotomine sand flies. This article focuses on several aspects (etiology, transmission, distribution, prevalence, risk factors, diagnosis, control, prevention, and public health significance) of CVBDs in Brazil and discusses research gaps to be addressed in future studies.

A influência das quedas na qualidade de vida de idosos

Abstract: The objective of this study is to analyze the effect of falls and their consequences on the quality of life of elderly people living in a low-income community in the city of Rio de Janeiro. This article is part of an explorative research conducted at CLAVES, using quantitative and qualitative methods. In this study we used quantitative data about falls and quality of life. 72 elderly aged over 60 years participated in the study. 51,4% of them were females, 20,8% lived alone and 37,5% admitted having suffered a fall during the last year. Among the most frequently mentioned consequences were fractures (24,3%), the fear of falling (88,5%), abandonment of activities (26,9%), change of habits (23,1%) and immobilization (19%). The analysis showed that falls have influence upon in the quality of life of the aged. The WHOQOL-Bref domain scores showed a reduction in the means of the group that had suffered falls during the last year in comparison to those who didn't fall, and the difference was more significant in the psychological field. In short, falls are frequent among the elderly and bring consequences that change the quality of life of these people in a negative way. Their incidence can be avoided by identifying the causes and developing appropriate preventive measures.

Embryonic desiccation resistance in Aedes aegypti: presumptive role of the chitinized Serosal Cuticle

Abstract: Background One of the major problems concerning dengue transmission is that embryos of its main vector, the mosquito Aedes aegypti, resist desiccation, surviving several months under dry conditions. The serosal cuticle (SC) contributes to mosquito egg desiccation resistance, but the kinetics of SC secretion during embryogenesis is unknown. It has been argued that mosquito SC contains chitin as one of its components, however conclusive evidence is still missing.

Molecular Detection and Characterization of Gastroenteritis Viruses Occurring Naturally in the Stream Waters of Manaus, Central Amazônia, Brazil

Abstract: To assess the presence of the four main viruses responsible for human acute gastroenteritis in a hydrographic network impacted by a disordered urbanization process, a 1-year study was performed involving water sample collection from streams in the hydrographic basin surrounding the city of Manaus, Amazonas, Brazil. Thirteen surface water sample collection sites, including different areas of human settlement characterized as urban, rural, and primary forest, located in the Taruma-Acu, Sao Raimundo, Educandos, and Puraquequara microbasins, were defined with a global positioning system. At least one virus was detected in 59.6% (31/52) of the water samples analyzed, and rotavirus was the most frequent (44.2%), followed by human adenovirus (30.8%), human astrovirus (15.4%), and norovirus (5.8%). The viral contamination observed mainly in the urban streams reflected the presence of a local high-density population and indicated the gastroenteritis burden from pathogenic viruses in the water, principally due to recreational activities such as bathing. The presence of viral genomes in areas where fecal contamination was not demonstrated by bacterial indicators suggests prolonged virus persistence in aquatic environments and emphasizes the enteric virus group as the most reliable for environmental monitoring.

Phylogeography and Genetic Variation of Triatoma dimidiata, the Main Chagas Disease Vector in Central America, and Its Position within the Genus Triatoma

Abstract: Background: Among Chagas disease triatomine vectors, the largest genus, Triatoma, includes species of high public health interest. Triatoma dimidiata, the main vector throughout Central America and up to Ecuador, presents extensive phenotypic, genotypic, and behavioral diversity in sylvatic, peridomestic and domestic habitats, and non-domiciliated populations acting as reinfestation sources. DNA sequence analyses, phylogenetic reconstruction methods, and genetic variation approaches are combined to investigate the haplotype profiling, genetic polymorphism, phylogeography, and evolutionary trends of T. dimidiata and its closest relatives within Triatoma. This is the largest interpopulational analysis performed on a triatomine species so far. Methodology and Findings: Triatomines from Mexico, Guatemala, Honduras, Nicaragua, Panama, Cuba, Colombia, Ecuador, and Brazil were used. Triatoma dimidiata populations follow different evolutionary divergences in which geographical isolation appears to have had an important influence. A southern Mexican‐northern Guatemalan ancestral form gave rise to two main clades. One clade remained confined to the Yucatan peninsula and northern parts of Chiapas State, Guatemala, and Honduras, with extant descendants deserving specific status. Within the second clade, extant subspecies diversity was shaped by adaptive radiation derived from Guatemalan ancestral populations. Central American populations correspond to subspecies T. d. dimidiata. A southern spread into Panama and Colombia gave the T. d. capitata forms, and a northwestern spread rising from Guatemala into Mexico gave the T. d. maculipennis forms. Triatoma hegneri appears as a subspecific insular form. Conclusions: The comparison with very numerous Triatoma species allows us to reach highly supported conclusions not only about T. dimidiata, but also on different, important Triatoma species groupings and their evolution. The very large intraspecific genetic variability found in T. dimidiata sensu lato has never been detected in a triatomine species before. The distinction between the five different taxa furnishes a new frame for future analyses of the different vector transmission capacities and epidemiological characteristics of Chagas disease. Results indicate that T. dimidiata will offer problems for control, although dwelling insecticide spraying might be successful against introduced populations in Ecuador.

Gastroschisis: international epidemiology and public health perspectives.

Abstract: Gastroschisis offers the intriguing epidemiological situation of a pandemic, strongly associated with very low maternal age. Identifying gastroschisis, and distinguishing it from the other abdominal wall defects, is theoretically easy but difficult in practice. The baseline birth prevalence of gastroschisis before the pandemic was approximately 1 in 50,000 births and has increased since between 10- and 20-fold. In many populations worldwide, it is still increasing. Such increasing prevalence and the association with very low maternal age are well proven, but the interaction between these two findings remains unknown. Geographic gradients (decreasing prevalence from North to South) are clear in Continental Europe and suggestive in Britain and Ireland. Gastroschisis seems more frequent in Caucasians compared to African Blacks and Orientals, and in Northern compared to Southern Europeans. These observations indicate the need for investigating gene-environment interactions. Since the global human situation is marked by inequalities among as well as within countries, the medical care and public health impact of gastroschisis varies widely among regions and social strata. The postnatal benefits of prenatal diagnosis of gastroschisis include family awareness; adequate planning of delivery with alerted obstetrical, pediatric, and surgical staff; optimal risk categorization, and personalized protocol for action. The increasing prevalence of gastroschisis combined with improved medical techniques to reduce morbidity and mortality are also increasing the burden and costs of this anomaly on health systems.

Amostras complexas em inquéritos populacionais: planejamento e implicações na análise estatística dos dados

Abstract: A avaliacao do desempenho dos sistemas de saude das nacoes vem ganhando importância crescente entre os gestores do setor saude. Entre os instrumentais de avaliacao do desempenho de saude, destacam-se os inqueritos nacionais de saude, cada vez mais utilizados para avaliar o estado de saude da populacao e a assistencia de saude prestada do ponto de vista do usuario. A maioria dos inqueritos nacionais de saude nao usa amostragem aleatoria simples, em parte por restricoes orcamentarias, em parte por limites de tempo associado a coleta de dados. Em geral, utiliza-se combinacao de varios metodos probabilisticos de amostragem para selecao de uma amostra representativa da populacao, chamada de desenho complexo de amostragem. Entre os metodos de amostragem mais utilizados conjuntamente, destacam-se a amostra aleatoria simples, a amostragem estratificada, e a amostragem por conglomerados. Resultante desse processo, a preocupacao subsequente e a analise de dados provenientes de amostras complexas. Este artigo trata de questoes relacionadas a analise estatistica de dados obtidos atraves de pesquisas com desenhos complexos de amostragem. Apresentam-se os problemas que ocorrem quando a analise estatistica nao incorpora a estrutura do plano amostral. Ao ignorar o desenho de amostragem, a analise estatistica tradicional, sob a suposicao de amostragem aleatoria simples, pode produzir incorrecoes tanto para as estimativas medias como para as respectivas variâncias, comprometendo os resultados, os testes de hipoteses e as conclusoes da pesquisa. Para a exemplificacao dos metodos, e utilizada a Pesquisa Mundial de Saude (PMS), realizada no Brasil em 2003.