The Role of the Cerebellum in Huntington's Disease: a Systematic Review.

Huntington's disease (HD) is a rare neurological disorder characterized by progressive motor, cognitive, and psychiatric disturbances. Although striatum degeneration might justify most of the motor symptoms, there is an emerging evidence of involvement of extra-striatal structures, such as the cerebellum. To elucidate the cerebellar involvement and its afferences with motor, psychiatric, and cognitive symptoms in HD. A systematic search in the literature was performed in MEDLINE, LILACS, and Google Scholar databases. The research was broadened to include the screening of reference lists of review articles for additional studies. Studies available in the English language, dating from 1993 through May 2020, were included. Clinical presentation of patients with HD may not be considered as the result of an isolated primary striatal dysfunction. There is evidence that cerebellar involvement is an early event in HD and may occur independently of striatal degeneration. Also, the loss of the compensation role of the cerebellum in HD may be an explanation for the clinical onset of HD. Although more studies are needed to elucidate this association, the current literature supports that the cerebellum may integrate the natural history of neurodegeneration in HD.

Neurology, psychiatry and the chess game: a narrative review.

The chess game comprises different domains of cognitive function, demands great concentration and attention and is present in many cultures as an instrument of literacy, learning and entertainment. Over the years, many effects of the game on the brain have been studied. Seen that, we reviewed the current literature to analyze the influence of chess on cognitive performance, decision-making process, linking to historical neurological and psychiatric disorders as we describe different diseases related to renowned chess players throughout history, discussing the influences of chess on the brain and behavior.

Is Ataxia an Underestimated Symptom of Huntington's Disease?

Background: Huntington's disease (HD) is a progressive disorder characterized by motor, cognitive and psychiatric features. Cerebellar ataxia is classically considered as uncommon in HD clinical spectrum. Objective: To determine the prevalence of cerebellar ataxia in patients with HD, both in the early and in the late stages of HD. Methods: Seventy-two individuals considered eligible were assessed by two trained doctors, applying the Scale for Assessment and Rating of Ataxia (SARA) and Brief Ataxia Rating Scale (BARS) for ataxia, the Unified Huntington's Disease Rating Scale (UHDRS) and also, Barthel Index (BI), in order to evaluate functional capacity. Results: Fifty-one patients (70.8%) presented with clinical ataxia at the time of examination (mean time of disease was 9.1 years). Six (8.33%) patients presented with cerebellar ataxia as first symptom. When stratified according to time of disease, a decline in the presence of chorea (p = 0.032) and an increase in cognitive deficit (p = 0.023) were observed in the patients as the disease progressed. The presence of ataxia was associated with longer duration of illness and severity of illness (UHDRS) (p < 0.0001), and shorter Barthel (less functionality) (p = 0.001). Conclusions: Cerebellar involvement may play an important role in natural history of brain degeneration in HD. The presence of cerebellar ataxia in HD is relevant and it may occur even in early stages, and should be included as part of the motor features of the disease.

Neurology, psychiatry and the chess game: a narrative review / Neurologia, psiquiatria e o jogo de xadrez: uma revisão narrativa

Abstract The chess game comprises different domains of cognitive function, demands great concentration and attention and is present in many cultures as an instrument of literacy, learning and entertainment. Over the years, many effects of the game on the brain have been studied. Seen that, we reviewed the current literature to analyze the influence of chess on cognitive performance, decision-making process, linking to historical neurological and psychiatric disorders as we describe different diseases related to renowned chess players throughout history, discussing the influences of chess on the brain and behavior.

Resumo O jogo de xadrez compreende diferentes domínios da função cognitiva, exige grande concentração e atenção e está presente em muitas culturas como instrumento de alfabetização, aprendizado e entretenimento. Ao longo dos anos, muitos efeitos do jogo no cérebro foram estudados. Dessa forma, revisamos a literatura atual para analisar a influência do xadrez no desempenho cognitivo, no processo de tomada de decisão, vinculando-a a distúrbios neurológicos e psiquiátricos históricos ao descrevermos diferentes doenças relacionadas a renomados jogadores de xadrez ao longo da história, discutindo as influências do xadrez no cérebro e no comportamento.

Matrix Metalloproteinase 2: A Possible Role inTooth Development and Eruption / Metaloproteinasa de matriz 2: Un posible papel en el desarrollo dental y la erupción

Abstract 18. Introduction: Tooth development results from a highly coordinated epithelial-mesenchyme interaction in which mesenchyme cells originate the dental papilla and dental follicle, while ectodermal cells originate the enamel organ. Simultaneously, bone tissue is formed around the developing tooth, trapping it in a bony crypt. Tooth eruption requires the resorption of the coronal part of the bony crypt, followed by degradation of the lamina propria, most likely by metalloproteinases (MMPs) activity. Objectives: The aim of this research was to determine MMP-2 expression in the dental germ cells (ameloblasts, odontoblasts, dental papilla and dental follicle) and surrounding tissues (alveolar bone and lamina propria) of rat molars throughout the eruptive process. Material and Methods: A total of 24 rats (4,6,9,11,14 and 16 days old) were used in this study. MMP-2 was detected through immunohistochemistry. A qualitative analysis was performed to investigate the expression of MMP2 in the dental germ cells, lamina propria, and coronal and basal regions of the bony crypt. Results: MMP-2 expression was observed in the dental papilla cells, dental follicle, ameloblasts, odontoblasts and bone cells from the coronal and basal regions of the bony crypt. MMP-2 was also detected in the lamina propria during the mucosal penetration stage of tooth eruption. Conclusion: We conclude that MMP-2 may be important for the extracellular matrix rearrangement necessary for tooth development and secretion of its mineralized tissues. We also conclude that MMP-2 may play a role in the extensive tissue remodeling during the intra-and-extra-osseous phases of the tooth eruption process.

Resumen 24. Introducción: el desarrollo del diente resulta de una interacción epitelial-mesénquima altamente coordinada en la cual las células mesénquima originan la papila dental y el folículo dental, mientras que las células ectodérmicas originan el órgano del esmalte. Simultáneamente, el tejido óseo se forma alrededor del diente en desarrollo y lo atrapa en una cripta ósea. La erupción dentaria requiere la resorción de la parte coronal de la cripta ósea, seguida de la degradación de la lámina propia, muy probablemente por la actividad metaloproteinasas (MMPs). Objetivos: el objetivo de esta investigación fue determinar la expresión de MMP-2 en las células germinales dentales (ameloblastos, odontoblastos, papila dentaria y folículo dentario) y tejidos circundantes (hueso alveolar y lámina propia) de molares de rata a lo largo del proceso eruptivo. Material y métodos: en este estudio se utilizó un total de 24 ratas (4,6,9,11,14 y 16 días de edad). MMP-2 se detectó a través de inmunohistoquímica. Un análisis cualitativo fue realizado para investigar la expresión de MMP-2 en las células de germen dentales, el lámina propria, y las regiones coronales y basales de la cripta ósea. Resultados: la expresión de MMP2 fue observada en las células de la papila dental, el folículo dental, el ameloblastos, el odontoblastos y las células del las regiones basales y coronales de la cripta ósea. La expresión de MMP-2 también se detectó en la lámina propia durante la etapa de penetración de la mucosa de la erupción dental. Conclusión: Concluimos que MMP-2 puede ser importante para el cambio extracelular de la matriz necesario para el desarrollo del diente y la secreción de sus tejidos mineralizados. También concluimos que MMP-2 puede desempeñar un papel en la remodelación extensa del tejido durante las fases intra y extraósea del proceso de erupción dental.