Neuroscience
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Widespread white matter (WM) microstructural abnormalities have been reported in patients with spinocerebellar ataxia type 3 (SCA3) using diffusion tensor imaging (DTI), whereas the ability of DTI to detect WM degeneration over short-term period remains insufficiently explored. Additionally, WM dysfunction remains entirely unknown in this disease. This study aims to investigate WM structural and functional alterations in SCA3, and provide promising progression biomarkers for short-term clinical trials. ⋯ The longitudinal analysis further showed decreased ALFF in the right PLIC and increased mean diffusivity in the left inferior cerebellar peduncle and right medial lemniscus over time in SCA3 patients. These findings emphasized that pons and the CST were the most vulnerable WM areas in SCA3, and have the potential to become therapeutic targets of SCA3 for upcoming interventional trials. In addition, both DT metrics and WM ALFF were efficient progression biomarkers for SCA3 even in short-term period.
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Review Meta Analysis
Potential similarities in gut microbiota composition between autism spectrum disorder and neurotypical siblings: Insights from a comprehensive meta-analysis.
Previous studies have explored the differences in gut microbiota (GM) between individuals with autism spectrum disorder (ASD) and neurotypical controls. However, factors such as diet, lifestyle, and environmental exposure influence GM, leading to significant variability, even among neurotypical individuals. Comparing the GM of ASD individuals with neurotypical siblings, who share similar genes and living conditions, may offer better insights into the GM mechanisms associated with ASD. Therefore, this study aims to analyze the GM composition in ASD by comparing it to that of neurotypical siblings, potentially identifying microbiota that influence ASD. ⋯ GM composition in ASD individuals closely resembles that of neurotypical siblings, with only a few unstable differences. This suggests that other crucial bacteria or certain interacting environmental factors play a role. Further studies are needed to gather stronger evidence to uncover the differences in GM and their mechanisms in ASD people.
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In two recent papers (Curr Trends Neurol 17: 83-98, 2023; J Neurophysiol 124: 1029-1044, 2020), James Lee has argued that his Transmembrane Electrostatically-Localized Cations (TELC) hypothesis offers a model of neuron transmembrane potentials that is superior to Hodgkin-Huxley classic cable theory and the Goldman-Hodgkin-Katz (GHK) equation. Here we examine critically the arguments in these papers, finding key weaknesses and fallacies. We also examine closely the literature cited by Lee, and find (i) strong support for the GHK equation; (ii) published measurements that contradict TELC predictions; and (iii) no convincing support for the TELC hypothesis.
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Local protein synthesis (LPS) in axons is now recognized as a physiological process, participating both in the maintenance of axonal function and diverse plastic phenomena. In the last decades of the 20th century, the existence and function of axonal LPS were topics of significant debate. Very early, axonal LPS was thought not to occur at all and was later accepted to play roles only during development or in response to specific conditions. ⋯ This review discusses key findings related to the localization and abundance of axonal mRNAs and their translation levels, both in basal states and in response to physiological processes, such as learning and memory consolidation, as well as neurodevelopmental and neurodegenerative disorders, including Alzheimer's disease, autism spectrum disorder, and axonal injury. Moreover, we discuss the current understanding of axonal ribosomes, from their localization to the potential roles of locally translated ribosomal proteins, in the context of emerging research that highlights the regulatory roles of the ribosome in translation. Lastly, we address the main challenges and open questions for future studies.
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Attention deficit hyperactivity disorder (ADHD) is one of the most frequent and disabling neurodevelopmental disorders. Recent research on cerebral blood flow (CBF) has enhanced understanding of the underlying pathophysiology in neuropsychiatric disorders. This systematic review aims to synthesize the existing literature on CBF anomalies among individuals with ADHD in comparison to controls. ⋯ This review highlights diverse CBF anomalies in ADHD. The most consistently reported findings suggest hypoperfusion during resting state in prefrontal and temporal areas, along with the basal ganglia, while there is a hyperperfusion in frontal, parietal and occipital regions. Further research, including longitudinal studies, is essential to develop a comprehensive understanding of CBF implications in ADHD.