Network Meta-analysis to Synthesize Evidence for Decision Making in Cardiovascular Research

Abstract Clinical decision-making requires synthesis of evidence from literature reviews focused on a specific theme. Evidence synthesis is performed with qualitative assessments and systematic reviews of randomized clinical trials, typically covering statistical pooling with pairwise meta-analyses. These methods include adjusted indirect comparison meta-analysis, network meta-analysis, and mixed-treatment comparison. These tools allow synthesis of evidence and comparison of effectiveness in cardiovascular research.

Estudos sobre accountability no Brasil: meta-análise de periódicos brasileiros das áreas de administração, administração pública, ciência política e ciências sociais

O artigo tem por objetivo identificar como o termo accountability tem sido tratado na literatura brasileira, considerando periódicos das áreas de administração, administração pública, ciência política e ciências sociais. Foram identificados e analisados 53 artigos. Os resultados indicaram que o tema ganhou mais relevância nos estudos a partir de 2006, tendo a Revista de Administração Pública (RAP) o maior número de publicações. Os artigos analisados, em sua maioria, são empíricos, e muitos apenas citam o termo accountability, sem defini-lo ou analisá-lo. Constatou-se que os artigos que discutem o tema apresentam uma clara confusão sobre o seu significado, sendo "responsabilização" e "prestação de contas" os termos mais citados nas definições. Acredita-se que este estudo torna-se relevante por, além de demonstrar a significação dada ao termo, também apontar os limites de sua utilização.

A efetividade do dentifrício fluoretado no controle da cárie dental: uma meta-análise

OBJETIVO: Realizar uma meta-análise sobre a efetividade da escovação com dentifrício fluoretado na redução da cárie dental para calcular o efeito das diferentes hipóteses testadas. MÉTODOS: Foram revisados artigos publicados sobre a efetividade da educação em saúde oral no período compreendido entre 1980 e 1998, indexados nas bases de dados Medline e Lilacs. Para avaliação da qualidade dos artigos, foram utilizados os critérios de rigor metodológico de Kay & Locker após serem submetidos a um comitê de experts formado por pesquisadores I-A do CNPq. Dos 43 artigos identificados, 22 (51,2%) atingiram os critérios de rigor metodológico propostos. O cálculo do tamanho do efeito da intervenção de cada estudo foi feito a partir das diferenças de resultados entre os grupos de teste e controle. O efeito global foi calculado para cada agrupamento de estudos segundo as hipóteses testadas. RESULTADOS: O aumento da concentração do flúor parece estar associado com o aumento do efeito (redução global = -0,17 IC 95% -0,22/-0,12). O maior percentual de redução de cárie foi verificado na comparação entre dentifrícios fluoretados e aqueles sem flúor (redução global = -0,29 IC 95% -0,34/-0,24). A adição de anti-microbianos (redução global = -0,03 IC 95% -0,07/+0,02), diferenças nos sistemas abrasivos (redução global = -0,02 IC 95% -0,09/+0,04) e diferenças nos princípios ativos não aumentam a efetividade dos mesmos (redução global = -0,04 IC 95% -0,10/+0,01). CONCLUSÕES: As maiores reduções de cárie foram encontradas nos estudos com escovação supervisionada. A síntese confirmou a importância da escovação com dentifrício fluoretado no controle da cárie dental. Contudo, aponta para uma ênfase nos aspectos medicamentosos relacionados ao controle da doença, em detrimento de ações educativas específicas. A heterogeneidade de resultados indica que sejam considerados os contextos de implantação das práticas preventivas no processo de sua avaliação.

Peso ao nascer e síndrome metabólica em adultos: meta-análise

OBJETIVO: Analisar as evidências na literatura do efeito do peso ao nascer sobre a ocorrência de síndrome metabólica em adultos. MÉTODOS: Foram pesquisados nas bases PubMed and LILACS, no período de 1966 a maio de 2006, artigos publicados usando os seguintes descritores: "birth weight" , "birthweight" , "intra-uterine growth restriction (IUGR)", "fetal growth retardation", "metabolic syndrome", "syndrome X", "Reaven's X syndrome". Foram selecionados 224 estudos considerados elegíveis que relatavam estimativas de associação entre peso ao nascer e síndrome metabólica ou seus componentes. Desses, 11 apresentavam razões de odds e foram usados na meta-análise. RESULTADOS: Com exceção de dois estudos, os demais relataram associação inversa entre peso ao nascer e síndrome metabólica. Comparadas com pessoas de peso normal, a razão de odds do efeito combinado naquelas que nasceram com baixo peso foi de 2,53 (IC 95%: 1,57;4,08). O gráfico de funil sugere viés de publicação e o resultado permanece estatisticamente significativo mesmo em estudos com mais de 400 pessoas (efeito combinado 2,37; IC 95%: 1,15;4,90). CONCLUSÕES: Baixo peso ao nascer aumenta o risco de síndrome metabólica na idade adulta.

Gender in the allocation of organs in kidney transplants: meta-analysis

OBJECTIVE To analyze whether gender influence survival results of kidney transplant grafts and patients.METHODS Systematic review with meta-analysis of cohort studies available on Medline (PubMed), LILACS, CENTRAL, and Embase databases, including manual searching and in the grey literature. The selection of studies and the collection of data were conducted twice by independent reviewers, and disagreements were settled by a third reviewer. Graft and patient survival rates were evaluated as effectiveness measurements. Meta-analysis was conducted with the Review Manager® 5.2 software, through the application of a random effects model. Recipient, donor, and donor-recipient gender comparisons were evaluated.RESULTS : Twenty-nine studies involving 765,753 patients were included. Regarding graft survival, those from male donors were observed to have longer survival rates as compared to the ones from female donors, only regarding a 10-year follow-up period. Comparison between recipient genders was not found to have significant differences on any evaluated follow-up periods. In the evaluation between donor-recipient genders, male donor-male recipient transplants were favored in a statistically significant way. No statistically significant differences were observed in regards to patient survival for gender comparisons in all follow-up periods evaluated.CONCLUSIONS The quantitative analysis of the studies suggests that donor or recipient genders, when evaluated isolatedly, do not influence patient or graft survival rates. However, the combination between donor-recipient genders may be a determining factor for graft survival.

Prevalence of hypertension among adolescents: systematic review and meta-analysis

ABSTRACT OBJECTIVE To estimate the prevalence of hypertension among adolescent Brazilian students. METHODS A systematic review of school-based cross-sectional studies was conducted. The articles were searched in the databases MEDLINE, Embase, Scopus, LILACS, SciELO, Web of Science, CAPES thesis database and Trip Database. In addition, we examined the lists of references of relevant studies to identify potentially eligible articles. No restrictions regarding publication date, language, or status applied. The studies were selected by two independent evaluators, who also extracted the data and assessed the methodological quality following eight criteria related to sampling, measuring blood pressure, and presenting results. The meta-analysis was calculated using a random effects model and analyses were performed to investigate heterogeneity. RESULTS We retrieved 1,577 articles from the search and included 22 in the review. The included articles corresponded to 14,115 adolescents, 51.2% (n = 7,230) female. We observed a variety of techniques, equipment, and references used. The prevalence of hypertension was 8.0% (95%CI 5.0–11.0; I2 = 97.6%), 9.3% (95%CI 5.6–13.6; I2 = 96.4%) in males and 6.5% (95%CI 4.2–9.1; I2 = 94.2%) in females. The meta-regression failed to identify the causes of the heterogeneity among studies. CONCLUSIONS Despite the differences found in the methodologies of the included studies, the results of this systematic review indicate that hypertension is prevalent in the Brazilian adolescent school population. For future investigations, we suggest the standardization of techniques, equipment, and references, aiming at improving the methodological quality of the studies.

Systematic reviews on leptospirosis

OBJECTIVES: To find the existing clinical evidence on interventions for leptospirosis. The objective is to evaluate the effectiveness and safety of any intervention on leptospirosis through systematic reviews of randomized controlled trials (RCTs). DATA SOURCE: The sources of studies used (where there were no limitations concerning language, date, or other restrictions) were: EMBASE, LILACS, MEDLINE, the Cochrane Controlled Clinical Trials Database, and the Cochrane Hepato-Biliary Group Randomized Trials register. SELECTION OF STUDIES: Type of Study: All systematic reviews of randomized controlled trials. Participants: patients with clinical and/or laboratorial diagnosis of leptospirosis, and subjects potencially exposed to leptospirosis as defined by the authors Interventions: any intervention for leptospirosis (as antibiotics or vaccines for prevention or treatment). DATA COLLECTION: The assessment will be independently made by the reviewers and cross-checked. The external validity was assessed by analysis of: studies, interventions, and outcomes. DATA SYNTHESIS: Located 163 studies using the search strategy described above, at the electronic databases above. Only 2 hits were selected, which are protocols of systematic reviews of Cochrane Collaboration, and not full reviews. One of the protocols evaluates antibiotics for treatment, and the other evaluates antibiotics for prevention of leptospirosis. CONCLUSIONS: There were not complete systematic reviews on interventions for leptospirosis. Any interventions for leptospirosis, such as prevention and treatment remains unclear for guidelines and practice.

ANTIFUNGAL ACTIVITY OF SILVER NANOPARTICLES OBTAINED BY GREEN SYNTHESIS

Silver nanoparticles (AgNPs) are metal structures at the nanoscale. AgNPs have exhibited antimicrobial activities against fungi and bacteria; however synthesis of AgNPs can generate toxic waste during the reaction process. Accordingly, new routes using non-toxic compounds have been researched. The proposal of the present study was to synthesize AgNPs using ribose as a reducing agent and sodium dodecyl sulfate (SDS) as a stabilizer. The antifungal activity of these particles against C. albicans and C. tropicalis was also evaluated. Stable nanoparticles 12.5 ± 4.9 nm (mean ± SD) in size were obtained, which showed high activity against Candida spp. and could represent an alternative for fungal infection treatment.

Evaluation of intrathecal synthesis of specific IgG antibodies against Toxoplasma gondii in the diagnosis assessment of presumptive toxoplasma encephalitis in aids patients

The diagnosis of neurotoxoplasmosis in patients with acquired immunodeficiency syndrome is mainly based on tomographic or magnetic resonance findings and on the response to specific treatment. We studied 55 patients with AIDS and neurotoxoplasmosis according to these diagnostic criteria (group 1), 37 patients with AIDS and neurological involvement of other etiology (group 2), and 16 anti-HIV-negative individuals with neurological manifestations (group 3). Serum and cerebrospinal fluid were examined for the presence of anti-T. gondii IgG, by indirect immunofluorescence. In 72 of them, the total amounts of these antibodies were determined in order to assess local production of anti-T. gondii antibodies in the central nervous system and to correlate their titers with infection activity in patients with AIDS and neurotoxoplasmosis. IgG titers > 1/64 in cerebrospinal fluid reached 100% specificity for the diagnosis of neurotoxoplasmosis in AIDS. Evidence of local synthesis of these antibodies was detected in 42.8% of patients of group 1, in 29.1% of patients of group 2 and in no patient of group 3. The test showed 70.8% specificity and therefore was not useful in our study for the differential diagnosis of neurotoxoplasmosis in patients with AIDS.

Liver synthesis function in chronic asymptomatic or oligosymptomatic alcoholics: correlation with other liver tests

Liver function and its correlation with bilirubin and hepatic enzymes were evaluated in 30 male chronic asymptomatic or oligosymptomatic alcoholics admitted into the psychiatric hospital for detoxification and treatment of alcoholism. Hypoalbuminemia, lowered prothrombin activity, hypotransferrinemia and hypofibrinogenemia were detected in 32 %, 32 %, 28 %, and 24 % of patients, respectively. Transferrin was elevated in 8 %. Greater prevalence of hyperbilirubinemia was found in patients with lowered prothrombin activity, hypofibrinogenemia, or hypotransferrinemia. No correlation was found between serum bilirubin or aminotransferase levels and normal or elevated albumin levels, time or activity of prothrombin, and fibrinogen levels. Serum alkaline phosphatase was elevated in normoalbuminemics and gamma-glutamyltransferase in patients with lowered prothrombin activity. Hypoalbuminemia was associated with hypofibrinogenemia, hypotransferrinemia with elevated aspartate aminotransferase or gamma-glutamyltransferase, and hypertransferrinemia with elevation of alanine aminotransferase. These data indicated the occurrence of hepatic dysfunction due to liver damage caused directly by alcohol or by alcoholism-associated nutritional deficiencies.

Inhaled nitric oxide in the management of persistent pulmonary hypertension of the newborn: a meta-analysis

OBJECTIVES: To evaluate the use of inhaled nitric oxide (NO) in the management of persistent pulmonary hypertension of the newborn. METHODS: Computerized bibliographic search on MEDLINE, CURRENT CONTENTS and LILACS covering the period from January 1990 to March 1998; review of references of all papers found on the subject. Only randomized clinical trials evaluating nitric oxide and conventional treatment were included. OUTCOMES STUDIED: death, requirement for extracorporeal membrane oxygenation (ECMO), systemic oxygenation, complications at the central nervous system and development of chronic pulmonary disease. The methodologic quality of the studies was evaluated by a quality score system, on a scale of 13 points. RESULTS: For infants without congenital diaphragmatic hernia, inhaled NO did not change mortality (typical odds ratio: 1.04; 95% CI: 0.6 to 1.8); the need for ECMO was reduced (relative risk: 0.73; 95% CI: 0.60 to 0.90), and the oxygenation was improved (PaO2 by a mean of 53.3 mm Hg; 95% CI: 44.8 to 61.4; oxygenation index by a mean of -12.2; 95% CI: -14.1 to -9.9). For infants with congenital diaphragmatic hernia, mortality, requirement for ECMO, and oxygenation were not changed. For all infants, central nervous system complications and incidence of chronic pulmonary disease did not change. CONCLUSIONS: Inhaled NO improves oxygenation and reduces requirement for ECMO only in newborns with persistent pulmonary hypertension who do not have diaphragmatic hernia. The risk of complications of the central nervous system and chronic pulmonary disease were not affected by inhaled NO.

Synthesis and antibiotic activity of some β-Carboline alkaloids

Nine β-carboline alkaloids were synthetized and screened for antibiotic activity. Six of the compounds testes showed inhibitory activity against one or more of the microorganisms assayed.

Myocardial repair with long-term and low-dose administration of a nitric oxide synthesis inhibitor. Myofibroblasts, type III collagen and fibronectin

OBJECTIVE: To study the healing process of the myocardium in hypertensive rats undergoing inhibition of nitric oxide synthesis. METHODS: Two groups of animals were studied: one received L-NAME, 12mg/kg/day, and the other was a control group. The presence of type III collagen, fibronectin, and alpha-smooth muscle actin-positive cells was assessed by immunohistochemistry. RESULTS: Fibronectin was seen in both early and late lesions, while type III collagen was seen mainly in areas of incomplete healing, situated among myocytes and around the intramyocardial branches of the coronary arteries. Areas representing early and late lesions showed a population of spindle-shaped cells. Immunohistochemistry showed that these cells were positive for alpha-smooth muscle actin. CONCLUSION: In the myocardium of hypertensive rats, the alpha-smooth muscle actin-positive cells are related to the accumulation of type III collagen and fibronectin in the areas of myocardial damage.