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1.
Front Med (Lausanne) ; 9: 962765, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36250095

RESUMO

Objective: The aim of this study was to assess the accuracy of prenatal imaging for the diagnosis of congenital Zika syndrome. Data sources: Medline (via Pubmed), PubMed, Scopus, Web of Science, and Google Scholar from inception to March 2022. Two researchers independently screened study titles and abstracts for eligibility. Study eligibility criteria: Observational studies with Zika virus-infected pregnant women were included. The index tests included ultrasound and/or magnetic resonance imaging. The reference standard included (1) Zika infection-related perinatal death, stillbirth, and neonatal death within the first 48 h of birth, (2) neonatal intensive care unit admission, and (3) clinically defined adverse perinatal outcomes. Synthesis methods: We extracted 2 × 2 contingency tables. Pooled sensitivity and specificity were estimated using the random-effects bivariate model and assessed the summary receiver operating characteristic (ROC) curve. Risk of bias was assessed using QUADAS 2 tool. The certainty of the evidence was evaluated with grading of recommendations. Results: We screened 1,459 references and included 18 studies (2359 pregnant women, 347 fetuses with confirmed Zika virus infection). Twelve studies (67%) were prospective cohorts/case series, and six (37%) were retrospective cohort/case series investigations. Fourteen studies (78%) were performed in endemic regions. Ten studies (56%) used prenatal ultrasound only, six (33%) employed ultrasound and fetal MRI, and two studies (11%) used prenatal ultrasound and postnatal fetal MRI. A total of six studies (ultrasound only) encompassing 780 pregnant women (122 fetuses with confirmed Zika virus infection) reported relevant data for meta-analysis (gestation age at which ultrasound imagining was captured ranged from 16 to 34 weeks). There was large heterogeneity across studies regarding sensitivity (range: 12 to 100%) and specificity (range: 50 to 100%). Under a random-effects model, the summary sensitivity of ultrasound was 82% (95% CI, 19 to 99%), and the summary specificity was 97% (71 to 100%). The area under the ROC curve was 97% (95% CI, 72 to 100%), and the summary diagnostic odds ratio was 140 (95% CI, 3 to 7564, P < 0.001). The overall certainty of the evidence was "very low". Conclusion: Ultrasound may be useful in improving the diagnostic accuracy of Zika virus infection in pregnancy. However, the evidence is still substantially uncertain due to the methodological limitations of the available studies. Larger, properly conducted diagnostic accuracy studies of prenatal imaging for the diagnosis of congenital Zika syndrome are warranted. Systematic review registration: Identifier [CRD42020162914].

2.
Syst Rev ; 10(1): 205, 2021 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-34274019

RESUMO

BACKGROUND: Biologic drugs such as adalimumab, etanercept, and infliximab represent major first-line and second-line treatments for rheumatoid arthritis (RA) patients. However, their high cost poses a massive burden on healthcare systems worldwide. The expiration of patents for these biologics has driven the production of biosimilar drugs, which are potentially less costly and remarkably similar, albeit not identical to the reference molecules. This paper aims to outline the protocol of a systematic review that will investigate the efficacy and safety profile of biosimilars compared to biologics (objective 1) and the impact of switching between biosimilar drugs and reference biologics on the management of RA patients (objective 2). METHODS: We will investigate the effects of any biosimilars of adalimumab, etanercept, and infliximab on RA patients. We will include randomized controlled trials (RCTs) or quasi-RCTs to assess efficacy and safety outcomes and RCTs with two- or multiple-part designs to evaluate the consequences of switching from reference biologics to biosimilar drugs (and vice-versa). Electronic searches will be performed through MEDLINE (via PubMed), EMBASE, LILACS, and CENTRAL (from inception to April 2021). Two independent reviewers will screen studies, extract data, and evaluate the risk of bias. The latter will be carried out considering specific domains from equivalence trials and switching studies. Random-effects models will be fitted to obtain summary estimates using either relative risk or standardized mean difference as a metric. The primary outcome will be the rate of treatment success according to the American College of Rheumatology 20 (ACR20), and the co-primary outcome will be the Health Assessment Questionnaire-Disability Index (HAQ-DI). Conclusions will be based on equivalence hypothesis testing using predefined margins of equivalence elicited from a group of experienced rheumatologists and prior studies. The overall certainty of the evidence will be assessed based on the GRADE system. DISCUSSION: The present investigation proposes a comprehensive, clinician-oriented approach to assess the equivalence and the impact of switching between biosimilars and biologics on the management of patients with RA. Our results will elucidate the efficacy, safety, immunogenicity of biosimilars, and the clinical consequences of substituting biologics with biosimilars in the management of RA. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42019137152 and CRD42019137155.


Assuntos
Antirreumáticos , Artrite Reumatoide , Medicamentos Biossimilares , Anticorpos Monoclonais/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Medicamentos Biossimilares/uso terapêutico , Humanos , Metanálise como Assunto , Revisões Sistemáticas como Assunto , Resultado do Tratamento
3.
Cad. saúde pública ; 29(supl.1): s45-s58, Nov. 2013. graf, tab
Artigo em Português | LILACS | ID: lil-690737

RESUMO

A mucopolissacaridose tipo II (MPS II) é uma doença genética de amplo espectro clínico, caracterizada por deficiência da enzima iduronato-2sulfatase. Revisão sistemática avaliou a eficácia e segurança da terapia de reposição enzimática (TRE) com idursulfase (IDS) na MPS II. As bases de dados PubMed/MEDLINE, Embase, LILACS e Biblioteca Cochrane foram pesquisados até 30 de novembro de 2012. Apenas cinco estudos preencheram os critérios de inclusão (ensaios clínicos randomizados - ECRs, ECRs abertos ou séries de caso prospectivas, incluindo cinco ou mais pacientes e avaliando desfechos relevantes). Metanálise foi realizada para capacidade vital forçada (CVF; valores absolutos e em %) e para a distância percorrida no teste da caminhada dos seis minutos, com mudanças significativas em ambas as variáveis; também foi encontrado risco aumentado de reações leves relacionadas à infusão e de desenvolvimento de anticorpos IgG à IDS. Em face dos dados apresentados neste estudo, conclui-se que a TRE com IDS é segura e tem benefício potencial em MPS II, mas estudos adicionais são necessários.


Mucopolysaccharidosis type II (MPS II) is a genetic disease of broad clinical spectrum, characterized by a deficiency of the enzyme iduronate2-sulfatase. The aim of this study was to assess whether enzyme replacement therapy (ERT) with idursulfase (IDS) for MPS II is effective and safe. PubMed/MEDLINE, Embase, LILACS, and Cochrane Library were searched until November 30, 2012. Only five articles met the inclusion criteria (randomized controlled trials - RCTs, or open-label trials/prospective case series including > 5 patients and evaluating relevant outcomes). A meta-analysis was performed for forced vital capacity (FVC; absolute and %) and for distance walked on the 6-minute walking test (6MWT). There was a statistically significant increase, but not clinically relevant, in both variables; an increased risk for development of mild infusion-related reactions and IgG antibodies to IDS were also found. The data suggest that ERT with IDS is safe and has a potential benefit for MPS II patients, but further studies are required.


La mucopolisacaridosis tipo II (MPS II) es una enfermedad genética de amplio espectro clínico, caracterizada por una deficiencia de la enzima iduronato-2-sulfatasa. El objetivo fue evaluar la seguridad y eficacia de la Terapia de Reemplazo Enzimático (TRE) con idursulfasa (IDS) en la MPS II. En las bases PubMed/MEDLINE, EMBASE, LILACS y Cochrane Library se inició la búsqueda hasta el 30 de noviembre de 2012. Sólo cinco estudios cumplieron los criterios de inclusión (ensayos controlados aleatorios -ECA, o ECA abiertos o series de casos prospectivo incluyendo > 5 pacientes y evaluación de los resultados pertinentes). El metaanálisis se realizó para la capacidad vital forzada (FVC; absoluta y %) y la distancia caminada en 6 minutos, con cambios significativos en ambas variables; el riesgo también se encuentra aumentado por reacciones leves y anticuerpos IgG, relacionados con la infusión con IDS. El TRE con IDS es seguro y tiene un beneficio potencial en la MPS II, pero se necesitan estudios adicionales.


Assuntos
Humanos , Terapia de Reposição de Enzimas/métodos , Iduronato Sulfatase/uso terapêutico , Mucopolissacaridose II/tratamento farmacológico , Iduronato Sulfatase/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto
4.
Cad Saude Publica ; 29 Suppl 1: S45-58, 2013 Nov.
Artigo em Português | MEDLINE | ID: mdl-25402250

RESUMO

Mucopolysaccharidosis type II (MPS II) is a genetic disease of broad clinical spectrum, characterized by a deficiency of the enzyme iduronate2-sulfatase. The aim of this study was to assess whether enzyme replacement therapy (ERT) with idursulfase (IDS) for MPS II is effective and safe. PubMed/MEDLINE, Embase, LILACS, and Cochrane Library were searched until November 30, 2012. Only five articles met the inclusion criteria (randomized controlled trials - RCTs, or open-label trials/prospective case series including > 5 patients and evaluating relevant outcomes). A meta-analysis was performed for forced vital capacity (FVC; absolute and %) and for distance walked on the 6-minute walking test (6MWT). There was a statistically significant increase, but not clinically relevant, in both variables; an increased risk for development of mild infusion-related reactions and IgG antibodies to IDS were also found. The data suggest that ERT with IDS is safe and has a potential benefit for MPS II patients, but further studies are required.


Assuntos
Terapia de Reposição de Enzimas/métodos , Iduronato Sulfatase/uso terapêutico , Mucopolissacaridose II/tratamento farmacológico , Humanos , Iduronato Sulfatase/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
JAMA ; 308(16): 1676-84, 2012 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-23093165

RESUMO

CONTEXT: Most medical interventions have modest effects, but occasionally some clinical trials may find very large effects for benefits or harms. OBJECTIVE: To evaluate the frequency and features of very large effects in medicine. DATA SOURCES: Cochrane Database of Systematic Reviews (CDSR, 2010, issue 7). STUDY SELECTION: We separated all binary-outcome CDSR forest plots with comparisons of interventions according to whether the first published trial, a subsequent trial (not the first), or no trial had a nominally statistically significant (P < .05) very large effect (odds ratio [OR], ≥5). We also sampled randomly 250 topics from each group for further in-depth evaluation. DATA EXTRACTION: We assessed the types of treatments and outcomes in trials with very large effects, examined how often large-effect trials were followed up by other trials on the same topic, and how these effects compared against the effects of the respective meta-analyses. RESULTS: Among 85,002 forest plots (from 3082 reviews), 8239 (9.7%) had a significant very large effect in the first published trial, 5158 (6.1%) only after the first published trial, and 71,605 (84.2%) had no trials with significant very large effects. Nominally significant very large effects typically appeared in small trials with median number of events: 18 in first trials and 15 in subsequent trials. Topics with very large effects were less likely than other topics to address mortality (3.6% in first trials, 3.2% in subsequent trials, and 11.6% in no trials with significant very large effects) and were more likely to address laboratory-defined efficacy (10% in first trials,10.8% in subsequent, and 3.2% in no trials with significant very large effects). First trials with very large effects were as likely as trials with no very large effects to have subsequent published trials. Ninety percent and 98% of the very large effects observed in first and subsequently published trials, respectively, became smaller in meta-analyses that included other trials; the median odds ratio decreased from 11.88 to 4.20 for first trials, and from 10.02 to 2.60 for subsequent trials. For 46 of the 500 selected topics (9.2%; first and subsequent trials) with a very large-effect trial, the meta-analysis maintained very large effects with P < .001 when additional trials were included, but none pertained to mortality-related outcomes. Across the whole CDSR, there was only 1 intervention with large beneficial effects on mortality, P < .001, and no major concerns about the quality of the evidence (for a trial on extracorporeal oxygenation for severe respiratory failure in newborns). CONCLUSIONS: Most large treatment effects emerge from small studies, and when additional trials are performed, the effect sizes become typically much smaller. Well-validated large effects are uncommon and pertain to nonfatal outcomes.


Assuntos
Interpretação Estatística de Dados , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Pesquisa Empírica , Metanálise como Assunto , Razão de Chances , Tamanho da Amostra
6.
PLoS One ; 6(1): e15656, 2011 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-21298044

RESUMO

A total of 172 persons from nine South Amerindian, three African and one Eskimo populations were studied in relation to the Paired box gene 9 (PAX9) exon 3 (138 base pairs) as well as its 5'and 3'flanking intronic segments (232 bp and 220 bp, respectively) and integrated with the information available for the same genetic region from individuals of different geographical origins. Nine mutations were scored in exon 3 and six in its flanking regions; four of them are new South American tribe-specific singletons. Exon3 nucleotide diversity is several orders of magnitude higher than its intronic regions. Additionally, a set of variants in the PAX9 and 101 other genes related with dentition can define at least some dental morphological differences between Sub-Saharan Africans and non-Africans, probably associated with adaptations after the modern human exodus from Africa. Exon 3 of PAX9 could be a good molecular example of how evolvability works.


Assuntos
Dentição , Evolução Molecular , Variação Genética , Fator de Transcrição PAX9/genética , África , Éxons , Geografia , Humanos , Inuíte , Mutação , América do Sul
7.
Obesity (Silver Spring) ; 19(6): 1244-51, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21233811

RESUMO

We investigated whether variants in major candidate genes for food intake and body weight regulation contribute to obesity-related traits under a multilocus perspective. We studied 375 Brazilian subjects from partially isolated African-derived populations (quilombos). Seven variants displaying conflicting results in previous reports and supposedly implicated in the susceptibility of obesity-related phenotypes were investigated: ß2-adrenergic receptor (ADRB2) (Arg16Gly), insulin induced gene 2 (INSIG2) (rs7566605), leptin (LEP) (A19G), LEP receptor (LEPR) (Gln223Arg), perilipin (PLIN) (6209T > C), peroxisome proliferator-activated receptor-γ (PPARG) (Pro12Ala), and resistin (RETN) (-420 C > G). Regression models as well as generalized multifactor dimensionality reduction (GMDR) were employed to test the contribution of individual effects and higher-order interactions to BMI and waist-hip ratio (WHR) variation and risk of overweight/obesity. The best multilocus association signal identified in the quilombos was further examined in an independent sample of 334 Brazilian subjects of European ancestry. In quilombos, only the PPARG polymorphism displayed significant individual effects (WHR variation, P = 0.028). No association was observed either with the risk of overweight/obesity (BMI ≥ 25 kg/m2), risk of obesity alone (BMI ≥ 30 kg/m2) or BMI variation. However, GMDR analyses revealed an interaction between the LEPR and ADRB2 polymorphisms (P = 0.009) as well as a third-order effect involving the latter two variants plus INSIG2 (P = 0.034) with overweight/obesity. Assessment of the LEPR-ADRB2 interaction in the second sample indicated a marginally significant association (P = 0.0724), which was further verified to be limited to men (P = 0.0118). Together, our findings suggest evidence for a two-locus interaction between the LEPR Gln223Arg and ADRB2 Arg16Gly variants in the risk of overweight/obesity, and highlight further the importance of multilocus effects in the genetic component of obesity.


Assuntos
Obesidade/genética , Obesidade/fisiopatologia , PPAR gama/genética , Polimorfismo de Nucleotídeo Único , Receptores Adrenérgicos beta 2/genética , Receptores para Leptina/genética , Adulto , Substituição de Aminoácidos , Pesos e Medidas Corporais , Brasil , Ingestão de Energia , Feminino , Estudos de Associação Genética , Humanos , Indígenas Sul-Americanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Redução Dimensional com Múltiplos Fatores , Tipagem de Sequências Multilocus , Obesidade/etnologia , Sobrepeso/etnologia , Sobrepeso/genética , Sobrepeso/fisiopatologia , Análise de Regressão , Caracteres Sexuais , População Branca
8.
Obesity (Silver Spring) ; 19(7): 1523-7, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21233812

RESUMO

The objective of the present study was to validate a recently reported synergistic effect between variants located in the leptin receptor (LEPR) gene and in the ß-2 adrenergic receptor (ADRB2) gene on the risk of overweight/obesity. We studied a middle-aged/elderly sample of 4,193 nondiabetic Japanese subjects stratified according gender (1,911 women and 2,282 men). The LEPR Gln223Arg (rs1137101) variant as well as both ADRB2 Arg16Gly (rs1042713) and Gln27Glu (rs1042714) polymorphisms were analyzed. The primary outcome was the risk of overweight/obesity defined as BMI ≥25 kg/m(2), whereas secondary outcomes included the risk of a BMI ≥27 kg/m(2) and BMI as a continuous variable. None of the studied polymorphisms showed statistically significant individual effects, regardless of the group or phenotype studied. Haplotype analysis also did not disclose any associations of ADRB2 polymorphisms with BMI. However, dimensionality reduction-based models confirmed significant interactions among the investigated variants for BMI as a continuous variable as well as for the risk of obesity defined as BMI ≥27 kg/m(2). All disclosed interactions were found in men only. Our results provide external validation for a male specific ADRB2-LEPR interaction effect on the risk of overweight/obesity, but indicate that effect sizes associated with these interactions may be smaller in the population studied.


Assuntos
Predisposição Genética para Doença , Obesidade/genética , Polimorfismo Genético , Receptores Adrenérgicos beta 2/genética , Receptores para Leptina/genética , Idoso , Substituição de Aminoácidos , Índice de Massa Corporal , Feminino , Frequência do Gene , Estudos de Associação Genética , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Redução Dimensional com Múltiplos Fatores , Sobrepeso/genética , Reprodutibilidade dos Testes , Caracteres Sexuais
9.
BMC Genet ; 12: 10, 2011 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-21251252

RESUMO

BACKGROUND: Genome wide association studies (GWAS) are becoming the approach of choice to identify genetic determinants of complex phenotypes and common diseases. The astonishing amount of generated data and the use of distinct genotyping platforms with variable genomic coverage are still analytical challenges. Imputation algorithms combine directly genotyped markers information with haplotypic structure for the population of interest for the inference of a badly genotyped or missing marker and are considered a near zero cost approach to allow the comparison and combination of data generated in different studies. Several reports stated that imputed markers have an overall acceptable accuracy but no published report has performed a pair wise comparison of imputed and empiric association statistics of a complete set of GWAS markers. RESULTS: In this report we identified a total of 73 imputed markers that yielded a nominally statistically significant association at P < 10 -5 for type 2 Diabetes Mellitus and compared them with results obtained based on empirical allelic frequencies. Interestingly, despite their overall high correlation, association statistics based on imputed frequencies were discordant in 35 of the 73 (47%) associated markers, considerably inflating the type I error rate of imputed markers. We comprehensively tested several quality thresholds, the haplotypic structure underlying imputed markers and the use of flanking markers as predictors of inaccurate association statistics derived from imputed markers. CONCLUSIONS: Our results suggest that association statistics from imputed markers showing specific MAF (Minor Allele Frequencies) range, located in weak linkage disequilibrium blocks or strongly deviating from local patterns of association are prone to have inflated false positive association signals. The present study highlights the potential of imputation procedures and proposes simple procedures for selecting the best imputed markers for follow-up genotyping studies.


Assuntos
Estudo de Associação Genômica Ampla/métodos , Estatística como Assunto , Algoritmos , Diabetes Mellitus Tipo 2/genética , Reações Falso-Positivas , Frequência do Gene , Marcadores Genéticos , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único
10.
Int J Epidemiol ; 40(2): 457-69, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21149279

RESUMO

BACKGROUND: Meta-analysis is increasingly being employed as a screening procedure in large-scale association studies to select promising variants for follow-up studies. However, standard methods for meta-analysis require the assumption of an underlying genetic model, which is typically unknown a priori. This drawback can introduce model misspecifications, causing power to be suboptimal, or the evaluation of multiple genetic models, which augments the number of false-positive associations, ultimately leading to waste of resources with fruitless replication studies. We used simulated meta-analyses of large genetic association studies to investigate naïve strategies of genetic model specification to optimize screenings of genome-wide meta-analysis signals for further replication. METHODS: Different methods, meta-analytical models and strategies were compared in terms of power and type-I error. Simulations were carried out for a binary trait in a wide range of true genetic models, genome-wide thresholds, minor allele frequencies (MAFs), odds ratios and between-study heterogeneity (τ²). RESULTS: Among the investigated strategies, a simple Bonferroni-corrected approach that fits both multiplicative and recessive models was found to be optimal in most examined scenarios, reducing the likelihood of false discoveries and enhancing power in scenarios with small MAFs either in the presence or in absence of heterogeneity. Nonetheless, this strategy is sensitive to τ² whenever the susceptibility allele is common (MAF ≥ 30%), resulting in an increased number of false-positive associations compared with an analysis that considers only the multiplicative model. CONCLUSION: Invoking a simple Bonferroni adjustment and testing for both multiplicative and recessive models is fast and an optimal strategy in large meta-analysis-based screenings. However, care must be taken when examined variants are common, where specification of a multiplicative model alone may be preferable.


Assuntos
Estudo de Associação Genômica Ampla , Modelos Genéticos , Frequência do Gene , Metanálise como Assunto , Razão de Chances , Polimorfismo de Nucleotídeo Único
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