Abstract Amyotrophic lateral sclerosis (ALS) is a complex and serious neurodegenerative disorder that develops in consequence of the progressive loss of the upper and lower motor neurons. Cases of ALS are classified as sporadic (sALS), or familial (fALS). Over 90% of cases are sALS, while roughly 10% are related to inherited genetic mutations (fALS). Approximately 70% of the genetic mutations that contribute to fALS have been identified. On the other hand, the majority of the sALS cases have an undetermined genetic contributor and few mutations have been described, despite the advanced genetic analysis methods. Also, several factors contribute to the onset and progression of ALS. Numerous lines of evidence indicate that epigenetic changes are linked to aging, as well as neurodegenerative disorders, such as ALS. In most cases, they act as the heritable regulation of transcription by DNA methylation, histone modification and expression of noncoding RNAs. Mechanisms involving aberrant DNA methylation could be relevant to human ALS pathobiology and therapeutic targeting. Despite advances in research to find factors associated with ALS and more effective treatments, this disease remains complex and has low patient survival. Here, we provide a narrative review of the role of DNA methylation for this complex neurodegenerative disorder.

O conhecimento tem sido estudado há bastante tempo dentro da área de Gestão. Entretanto, a partir da década de 1990, com o crescimento da economia baseada em ativos intangíveis, as empresas passaram a preocupar-se com o conhecimento existente em suas organizações, assim como com o seu gerenciamento. Assim, o objetivo deste trabalho é identificar, exploratoriamente, por meio de um estudo de caso, quais são os fatores relevantes à transferência de conhecimento tácito em uma grande empresa petrolífera brasileira. A presente pesquisa analisa parte relevante da bibliografia acerca da transferência de conhecimento tácito em organizações e, usando abordagem quantitativa baseada em análise fatorial exploratória, coleta evidências visando a identificar, exploratoriamente, os fatores-chave de sucesso à transferência de conhecimento tácito nessa organização em questão. Como resultado final do trabalho, fatores idiossincráticos, a estratégia de gestão do conhecimento adotada pela empresa e a sua estrutura organizacional são identificados como elementos-chave ao sucesso na transferência de conhecimento tácito na organização. Por fim, são consolidadas e apresentadas proposições derivadas dos resultados obtidos - de modo que sejam testadas em estudo explanatório ulterior -, assim como elencadas as limitações da pesquisa em questão.

Knowledge and management of such knowledge have been studied for some time now in the field of Management. However, in the 1990s, with the growth in the economy based on intangible assets, companies needed more than an unstructured approach to corporate knowledge management to succeed in this new competitive environment. Therefore, this article aims to identify, in an exploratory way, the relevant factors for tacit knowledge transfer within a major Brazilian oil company trough a case study. This study reviews the literature concerning tacit knowledge transfer within organizations, and using a quantitative approach based on exploratory factorial analysis, it collects facts in order to identify the relevant factors for tacit knowledge transfer within the organization under study. It can be said that idiosyncratic factors, the knowledge management strategy adopted by the company, and its organizational structure are the critical elements for the success of tacit knowledge transfer within the organization under analysis. Finally, three propositions arising from the results obtained are then consolidated and presented in order that they may be tested in a future explanatory study and the research limitation are unveiled.