Resilience of Neural Cellularity to the Influence of Low Educational Level.

BACKGROUND: Education is believed to contribute positively to brain structure and function, as well as to cognitive reserve. One of the brain regions most impacted by education is the medial temporal lobe (MTL), a region that houses the hippocampus, which has an important role in learning processes and in consolidation of memories, and is also known to undergo neurogenesis in adulthood. We aimed to investigate the influence of education on the absolute cell numbers of the MTL (comprised by the hippocampal formation, amygdala, and parahippocampal gyrus) of men without cognitive impairment. METHODS: The Isotropic Fractionator technique was used to allow the anisotropic brain tissue to be transformed into an isotropic suspension of nuclei, and therefore assess the absolute cell composition of the MTL. We dissected twenty-six brains from men aged 47 to 64 years, with either low or high education. RESULTS: A significant difference between groups was observed in brain mass, but not in MTL mass. No significant difference was found between groups in the number of total cells, number of neurons, and number of non-neuronal cells. Regression analysis showed that the total number of cells, number of neurons, and number of non-neuronal cells in MTL were not affected by education. CONCLUSIONS: The results indicate a resilience of the absolute cellular composition of the MTL of typical men to low schooling, suggesting that the cellularity of brain regions is not affected by formal education.

Hiit e insuficiência cardíaca: onde estamos e para onde vamos? / Hiit and heart failure: where are we and where are we going?

INTRODUÇÃO: O treinamento físico é essencial para indivíduos saudáveis e cardiopatas. Segundo a Sociedade Brasileira de Cardiologia, a reabilitação cardiovascular para pacientes com insuficiência cardíaca crônica (ICC) estável, em classe funcional II-III da New York Heart Association, resulta em melhora da qualidade de vida e capacidade funcional e tem sido classe de recomendação I e nível de evidência A. Diferentes estratégias de treinamento físico são capazes de aumentar a aptidão física e cardiovascular, dentre as mais utilizadas estão o Treinamento Contínuo de Moderada Intensidade (MCT) e o Treinamento Intervalado de Alta Intensidade (HIIT). Estudos anteriores compararam os efeitos do HIIT com o MCT, em indivíduos saudáveis, porém, poucos demonstraram seus efeitos em cardiopatas, assim, o objetivo deste estudo foi avaliar a eficácia do HIIT no treinamento de pacientes com ICC. MÉTODOS: A seleção foi realizada nas bases de dados PubMed, Biblioteca Virtual em Saúde e Cochrane Library de agosto de 2018 a fevereiro de 2019 utilizando os descritores: Insuficiência Cardíaca e Treinamento Intervalado de Alta Intensidade. Os critérios de inclusão consistiu em pesquisas que fossem ensaios clínicos randomizados em seres humanos, publicados em revistas indexadas, que apresentassem avaliações de intervenções e efeitos do HIIT em pacientes com ICC com duração mínima de 4 semanas. RESULTADOS: Na busca inicial foram acessados um total de 178 estudos e foram eleitos os 19 que preencheram os critérios de elegibilidade. Estes incluíram um total de 824 pacientes (83,6% homens, 16,4% mulheres) com ICC de etiologias diversas. Nossos achados salientam que até o presente momento, o HIIT se apresenta como uma estratégia de treinamento físico bem tolerado e seguro para pacientes com ICC (com e sem redução da Fração de Ejeção Ventricular Esquerda). Neste sentido, nossa revisão sistemática evidenciou efeitos significativos na melhoria dos parâmetros de aptidão física/ capacidade cardiorrespiratória, eficiência metabólica e ventilatória, porém, na análise global sem apresentar superioridade sobre o MCT. O HIIT permite aos pacientes se exercitarem com maior potência e similar tolerância do MCT, além de reverter a miopatia esquelética, contribuindo para induzir a hipertrofia muscular nessa população. CONCLUSÃO: O HIIT mostrou ser um método de treinamento seguro em pacientes com ICC, no entanto, até os últimos estudos não foi possível provar a sua superioridade sobre o MCT, sendo necessários novos estudos sobre o HIIT nesta população de grande relevância e implicância clínica. (AU)

Chronic Traumatic Encephalopathy Presenting as Alzheimer's Disease in a Retired Soccer Player.

The relationship between soccer and chronic traumatic encephalopathy (CTE) is not well established. We report clinicopathological correlations in an 83-year-old retired center-back soccer player, with no history of concussion, manifesting typical Alzheimer-type dementia. Examination revealed mixed pathology including widespread CTE, moderate Alzheimer's disease, hippocampal sclerosis, and TDP-43 proteinopathy. This case adds to a few CTE cases described in soccer players. Furthermore, it corroborates that CTE may present clinically as typical Alzheimer-type dementia. Further studies investigating the extent to which soccer is a risk for CTE are needed.

Higher Prevalence of TDP-43 Proteinopathy in Cognitively Normal Asians: A Clinicopathological Study on a Multiethnic Sample.

Transactive response DNA binding protein 43 (TDP-43) proteinopathy is the major hallmark of frontotemporal lobar degeneration and amyotrophic lateral sclerosis. It is also present in a subset of Alzheimer's disease cases. Recently, few reports showed TDP-43 changes in cognitively normal elderly. In Caucasians, TDP-43 proteinopathy independently correlate with cognitive decline. However, it is challenging to establish direct links between cognitive and/or neuropsychiatric symptoms and protein inclusions in neurodegenerative diseases because individual cognitive reserves modify the threshold for clinical disease expression. Cognitive reserve is influenced by demographic, environmental and genetic factors. We investigated the relationships between demographic, clinical and neuropathological variables and TDP-43 proteinopathy in a large multiethnic sample of cognitively normal elderly. TDP-43 proteinopathy was identified in 10.5%, independently associated with older age (P = 0.03) and Asian ethnicity (P = 0.002). Asians showed a higher prevalence of TDP-43 proteinopathy than Caucasians, even after adjustment for sex, age, Braak stage and schooling (odds ratio = 3.50, confidence interval 1.41-8.69, P = 0.007). These findings suggested that Asian older adults may be protected from the clinical manifestation of brain TDP-43 proteinopathy. Future studies are needed to identify possible race-related protective factors against clinical expression of TDP-43 proteinopathies.