Diabetes mellitus tipo 1: multifatores que conferem suscetibilidade à patogenia auto-imune = Type 1 diabetes mellitus: multifactors that confer susceptibility to the autoimmune pathogenesis

Objetivos: revisar dados de literatura concernentes aos fatores que conferem suscetibilidade à patogenia auto-imune do diabetes mellitus tipo 1. Fonte de dados: revisão de artigos especializados no assunto publicados em bancos de dados nacionais e internacionais (SCIELO, LILACS e PUBMED). Síntese de dados: a etiopatogenia do diabetes mellitus tipo 1 está associada a fatores inflamatórios, genéticos e ambientais. Nesta revisão, abordamos o papel da auto-imunidade humoral e celular que culmina com a disfunção das células-beta produtoras de insulina. A precocidade da presença de alguns autoanticorpos como anti-ilhotas pancreáticas, antiinsulina e anti-ácido glutâmico descarboxilase é uma característica importante nesta patologia. Os diversos fatores genéticos associados ao deflagramento do diabetes mellitus tipo 1, sobretudo os associados ao sistema de antígenos leucocitários humanos, acabam por potencializar a apresentação de antígenos das ilhotas para o sistema imune. Por fim, fatores ambientais como exposição viral também contribuem para a quebra de tolerância imunológica observada nesses pacientes. Conclusões: o diabetes mellitus tipo 1 é uma entidade de etiopatogenia altamente complexa. Diversos fatores genéticos e ambientais potencializam os mecanismos de auto-imunidade humoral e celular que levam à insulite. O risco de hipoglicemia severa observada com o tratamento insulínico e as complicações crônicas do diabetes mellitus tipo 1 justificam pesquisas contínuas em relação à etiopatogenia desta entidade, o que contribuirá para abordagens terapêuticas mais eficazes. <br> Aims: To review the literature data concerning the factors which confer susceptibilitiy to the autoimmune pathogenesis of type I diabetes mellitus. Source of data: Review of specific articles on the issue published in national and in-ternational databases (SCIELO, LILACS, PUBMED). Summary of the findings: The etiopathogenesis of type I diabetes mellitus is associated to immunoinflammatory, genetic, and environmental factors. In this review, we approach the role of humoral (autoantibodies) and cellular autoimmunity which culminate with the disfunction of insulin-producers beta-cells. The precocity of the presence of some autoantibodies such as anti-islet cell antibodies, anti-insulin and anti-GAD65 are important characteristics of this pathology. The diverse genetic factors related to development of type 1 diabetes mellitus, mostly those linked to the human leucocyte antigen system, surely increment the apresentation of islet antigens to the immune system. Lastly, environmental factors, such as viral exposure, also contribute to the break of immunological tolerance observed in these patients. Conclusions: Type 1 diabetes mellitus has a highly complex etiopathogenesis. A variety of genetic and environmental factors potentialize the mechanisms of humoral and cellular autoimmunity which generate insulitis. The risk of severe hypoglicemia usually seen with insulin therapy and the chronic complications related to type 1 diabetes mellitus justify continuous research on the etiopathogenesis of this entity, so providing new therapeutic strategies

A brief history of antiphospholipid antibodies and antiphospholipid syndrome = Uma breve história dos anticorpos antifosfolípides e da síndrome antifosfolípide

OBJETIVOS: Revisar os relatos históricos sobre anticorpos antifosfolípides (aAF) dos primeiros anos do século XX; delinear as características cardinais da síndrome antifosfolípide (SAF) a partir de 1983, incluindo critérios clínicos, etiopatogênese e terapia atual. MÉTODOS: Revisão de literatura utilizando o PubMed. Foram selecionados artigos com foco na história dos aAF e da SAF. RESULTADOS: Os aAF foram originalmente descritos em pacientes com sífilis ainda em 1906 por Wassermann. Uma primeira definição do anticoagulante lúpico foi proposta em 1963, enquanto o anticorpo anticardiolipina (aCL) foi descrito 20 anos mais tarde. A SAF, inicialmente reportada por Hughes em 1985 como "síndrome do aCL" é uma das mais prevalentes trombofilias adquiridas. Tromboses arteriais e venosas, associadas ou não à morbidade gestacional, compreendem os achados principais. É uma nova entidade, tendo sido primeiramente associada ao lupus eritematoso sistêmico. Uma forma primária de SAF foi reconhecida em1989, e muitas variantes de SAF são modernamente conhecidas. A terapia-padrão para a SAF trombótica é a anticoagulação plena e ininterrupta. Na SAF obstétrica, a combinação de ácido acetil-salicílico com enoxaparina tem-se mostrado altamente efetiva. CONCLUSÕES: A caracterização sequencial dos aAF desde Wasserman em 1906, e mais tarde da SAF nos anos 1980, é um interessante exemplo de como uma nova entidade é concebida passo a passo. A SAF é uma nova e intrigante causa de trombofilia autoimune, com uma complexa patogênese e uma pletora de manifestações clínicas e laboratoriais. O tratamento é baseado em anticoagulação contínu

Height and body-mass index trajectories of school-aged children and adolescents from 1985 to 2019 in 200 countries and territories: a pooled analysis of 2181 population-based studies with 65 million participants

Summary Background Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents. Methods For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5–19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence. Findings We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9–10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing countries, but they became progressively less healthy compared with their comparators as they grew older by not growing as tall (eg, boys in Austria and Barbados, and girls in Belgium and Puerto Rico) or gaining too much weight for their height (eg, girls and boys in Kuwait, Bahrain, Fiji, Jamaica, and Mexico; and girls in South Africa and New Zealand). In other countries, growing children overtook the height of their comparators (eg, Latvia, Czech Republic, Morocco, and Iran) or curbed their weight gain (eg, Italy, France, and Croatia) in late childhood and adolescence. When changes in both height and BMI were considered, girls in South Korea, Vietnam, Saudi Arabia, Turkey, and some central Asian countries (eg, Armenia and Azerbaijan), and boys in central and western Europe (eg, Portugal, Denmark, Poland, and Montenegro) had the healthiest changes in anthropometric status over the past 3·5 decades because, compared with children and adolescents in other countries, they had a much larger gain in height than they did in BMI. The unhealthiest changes—gaining too little height, too much weight for their height compared with children in other countries, or both—occurred in many countries in sub-Saharan Africa, New Zealand, and the USA for boys and girls; in Malaysia and some Pacific island nations for boys; and in Mexico for girls. Interpretation The height and BMI trajectories over age and time of school-aged children and adolescents are highly variable across countries, which indicates heterogeneous nutritional quality and lifelong health advantages and risks

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight NCD Risk Factor Collaboration (NCD-RisC)

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions