ECMOFOBIA, porque 14 picadelas por dia deixam qualquer um ecmofóbico...

quarta-feira, 25 de fevereiro de 2015

PLOS ONE: Covariation of the Incidence of Type 1 Diabetes with Country Characteristics Available in Public Databases

PLOS ONE: Covariation of the Incidence of Type 1 Diabetes with Country Characteristics Available in Public Databases

Aqui fica a introdução de um estudo que me parece bastante interessante. Leia tudo no link acima.


It has long been noticed that the incidence of Type 1 Diabetes (T1D) is highly variable from one country to another. For example, the 62.42/100.000 persons/year incidence found in Finland [1] was 780-fold larger than the 0.08/100.000 persons/year incidence in Papua New Guinea [2]; differences in T1D incidence are also observed between countries where the health care systems are comparable. The variability of T1D incidence is even visible within countries; for example, in Italy, T1D incidence varied between 54.4/100.000 persons/year in Sardinia [3] and 4.4/100.000 persons/year in Lombardia [4]. The reason for these differences is not precisely known, but is most unlikely due to classification bias, as the disease cannot go untreated, and the diagnosis is relative easy to perform in children [5]. The country-to-country T1D variability is known to be partly explained by genetic variations. Indeed, HLA (human leukocyte antigen) and 33 other genes are associated with elevated risk of T1D (T1Dbase Version 4.18 updated on 30/9/2014 available at [511]. The genetic characteristics of several populations have been found to—at least partially—explain the level of their T1D incidence [12]. For example, the low incidence in Japan, and more generally in southeast Asia, was strongly associated with the absence of highly susceptible haplotypes, such as DRB1*03-DQB1*0201 and DRB1*04-DQB1*0302 found in Caucasian populations [13] or DRB1*030101-DQB1*0201 [14] found in Arab populations (Bahrainis, Lebanese, and Tunisians). Instead, the major susceptible HLA haplotypes in the Japanese and Korean populations were DRB1*0405-DQB1*0401 and DRB1*0901-DQB1*0303 [15].
Another peculiarity of T1D epidemiology is that a dramatic increase of the incidence (on average 3% per year [16]) was observed over the last decades in many countries, in particular European countries with previously low incidences. This increase cannot be explained by genetic factors, since the genetic structure of these countries cannot have varied greatly over such a short period of time. The reasons are more likely to be found in environmental factors (taking here environment broadly, as encompassing physical, chemical, social and life-style factors). However, no single environmental factor, or configuration of factors, that could explain the patterns of differences has ever been identified. More likely, there are complex networks of environmental causes, and of gene-environmental causes that remain to be discovered.
The search of genetic factors of T1D was facilitated during the last 10 years by the GWAS (genome-wide association studies) technology that replaced the gene candidate approaches and instead scanned the entire genome to find SNPs (Single-Nucleotide Polymorphisms) that were significantly associated with T1D [17]. The discovery of an SNP was not the discovery of a “gene”, but was a marker leading to the possible discovery of a gene. Here, we translate this data-driven approach to search for environmental markers related to variations of T1D incidence that might eventually lead to environmental causes, possibly in interaction with genetic factors. One could indeed expect that, in this age of information, plenty of environmental characteristics could be readily available, insofar as local and global organizations collect such data, and provide them free to researchers, with easy interface on the Internet. A limitation commonly advocated is that country statistics are in many cases of too low quality. However, for two related reasons, this argument does not hold, or will not hold for long: a) why collect, maintain and publish such statistics if they cannot be used by researchers? and b) how can one encourage a better quality for these statistics—meaning more resources devoted to them—if they are never used?
Here, we present the attempt we made to use open public data to identify climate and environmental, demographic, economic, and health characteristics correlated with variations in T1D incidence between countries.'

terça-feira, 17 de fevereiro de 2015

Diabetes tipo 1: desenvolvida insulina inteligente | ALERT® ONLINE - PT

Diabetes tipo 1: desenvolvida insulina inteligente | ALERT® ONLINE - PT

'Diabetes tipo 1: desenvolvida insulina inteligente
Estudo publicado na “Proceedings of the National Academy of Sciences”
12 fevereiro 2015

Investigadores americanos desenvolveram uma insulina de longa duração, a Ins-PBA-F, que se auto-ativa quando os níveis de glucose aumentam, dá conta um estudo publicado na revista “Proceedings of the National Academy of Sciences”.

Os investigadores da Universidade de Utah, nos EUA, verificaram em modelos de ratinhos que os efeitos de uma injeção deste tipo de insulina duram pelo menos 14 horas, período durante o qual pode reduzir repetidamente e automaticamente os níveis de glucose no sangue após a administração de quantidades de glucose comparáveis às ingeridas na alimentação.
Os pacientes com diabetes tipo 1 têm de monitorizar os seus níveis de açúcar várias vezes ao dia e determinar quando e quanta insulina devem administrar. Um erro de cálculo ou um lapso na administração de insulina pode fazer com que os níveis de glucose atinjam níveis demasiado elevados (hiperglicemia), conduzindo possivelmente a doenças cardíacas, cegueira ou outras complicações a longo prazo. Por outro lado, se os níveis de glucose atingirem níveis muito baixos (hipoglicemia) pode induzir o coma ou levar mesmo à morte.

Apesar dos avanços em torno do tratamento da diabetes, como bombas de insulina e o desenvolvimento de quatro tipos de insulina, os pacientes continuam a ter que ajustar manualmente a quantidade de insulina administrada diariamente. Os níveis de glucose variam bastante em função de vários fatores, incluindo alimentação e prática de exercício físico.

Deste modo, uma insulina sensível à glucose que é ativada automaticamente quando os níveis de açúcar no sangue são muito elevados, eliminaria a necessidade de injeções adicionais e reduziria os perigos associados a uma quantificação incorreta. Apesar de estarem em desenvolvimento várias insulinas “inteligentes”, muitas delas apresentam efeitos secundários indesejáveis.

Esta nova insulina inteligente, a Ins-PBA-F, foi criada através da modificação química da insulina. Esta insulina consiste num derivado da insulina de ação prolongada que tem um motivo químico, o ácido fenilborónico, num dos extremos. Em condições normais a Ins-PBA-F liga-se a proteínas séricas que circulam na corrente sanguínea, bloqueando a sua atividade. Quando os níveis de glucose são demasiado elevados estes ligam-se ao ácido fenilborónico fazendo com que a Ins-PBA-F seja libertada.
O estudo apurou ainda que a Ins-PBA-F é mais rápida a diminuir os níveis de glucose do que a insulina de ação prolongada detemir.

De acordo com um dos autores do estudo, Danny Chou, como a Ins-PBA-F é uma versão quimicamente modificada de uma hormona natural, é muito provável que seja segura o suficiente para ser utilizada numa base diária, de um modo semelhante a outros derivados de insulina que já estão atualmente no mercado.'

ALERT Life Sciences Computing, S.A.

sábado, 7 de fevereiro de 2015

Re-educating the Immune System in T1D | JDRF: Improving Lives. Curing Type 1 Diabetes

Re-educating the Immune System in T1D | JDRF: Improving Lives. Curing Type 1 Diabetes

"In a recent publication in the prestigious scientific journal, Proceedings of the National Academy of Sciences, JDRF partner Selecta published the details of a novel technology that is being used to develop a vaccine for the induction of immune tolerance in people with T1D. Their technique involves creating tiny packages called nanoparticles containing the T1D antigens and immunomodulatory agents that ultimately reach the key cells of the immune system and trigger the re-education process. Selecta is one of the leaders in the development of antigen-specific immune tolerance therapies and their approach holds great promise for T1D. With recently renewed support from a JDRF-Sanofi partnership, Selecta is set to begin testing this antigen-specific immune therapy in mouse models of T1D. If successful, this could pave the way for pilot clinical studies and ultimately a means to restore normal immune function and halt the T1D disease process.
For more information or to support the JDRF restoration research program, please click here."