Different sleep patterns during the COVID-19 pandemic: association with mood, exercise and light exposure.

The aim was to evaluate the sleep-wake cycle pattern, mood, perceived stress and some behaviors, such as physical exercise and exposure to natural light of college students during the COVID-19 pandemic. This is a cross-sectional study conducted between June and August 2020 using an electronic form provided by Google. The sample consisted of undergraduate students aged between 18 and 30 years old and residents of the northeast region of Brazil. The students generally had sleepiness and poor sleep quality, high levels of anxiety, mild to moderate depressive symptoms and moderate perceived stress. Some of these aspects were worse in women. The college students showed three sleep patterns: one group had good sleep quality without excessive daytime sleepiness; another group had poor sleep quality, but no excessive daytime sleepiness; and a third group had high daytime sleepiness, and less expressive sleep quality impairment. Greater exposure to sunlight and practicing physical exercise predominated in individuals with better sleep quality, suggesting that they are protective factors. In addition, excessive daytime sleepiness and poor sleep quality were separately associated with higher anxiety, depression and stress perception levels, proving to be important aspects for care in order to favor mental health during the pandemic. In conclusion, it is suggested that the COVID-19 pandemic affected the sleep of college students in a heterogeneous way. The differentiated sleep patterns are associated with exposure to natural light and exercising.

Environmental enrichment changes the effects of prenatal and postnatal undernutrition on memory, anxiety traits, Bdnf and TrkB expression in the hippocampus of male adult rats.

Environmental factors such as undernutrition and environmental enrichment can promote changes in the molecular and behavioural mechanisms related to cognition. Herein, we investigated the effect of enriched environment stimulation in rats that were malnourished in the pre- and postnatal periods on changes in the gene expression of brain-derived neurotrophic factor and its receptor in the hippocampus, as well as on anxiety traits and memory. Early undernutrition promoted weight reduction, increased the risk analysis, reduced permanence in the open arm of the elevated plus-maze and induced a reduction in the gene expression of brain-derived neurotrophic factor and tropomyosin receptor kinase B. However, exposure to an enriched environment from 30 to 90 days' old maintained the malnourished phenotype, leading to weight reduction in the control group. In addition, the enriched environment did not alter the risk assessment in the undernourished group, but it did increase the frequency of labyrinth entries. Sixty-day exposure to the enriched environment resulted in a reversal in the gene expression of brain-derived neurotrophic factor and tropomyosin receptor kinase B in the hippocampus of malnourished rats and favoured of long-term memory in the object recognition test in the open-field. These results suggest that an enriched environment may have a protective effect in adult life by inducing changes in long-term memory and anxiety traits in animals that were undernourished in early life. Furthermore, reversing these effects of undernutrition involves mechanisms linked to the molecular signalling of brain-derived neurotrophic factor and tropomyosin receptor kinase B in the hippocampus.

Transcriptomic effects of propranolol and primidone converge on molecular pathways relevant to essential tremor.

Essential tremor (ET) is one of the most common movement disorders, affecting nearly 5% of individuals over 65 years old. Despite this, few genetic risk loci for ET have been identified. Recent advances in pharmacogenomics have previously been useful to identify disease related molecular targets. Notably, gene expression has proven to be quite successful for the inference of drug response in cell models. We sought to leverage this approach in the context of ET where many patients are responsive to two drugs: propranolol and primidone. In this study, cerebellar DAOY and neural progenitor cells were treated for 5 days with clinical concentrations of propranolol and primidone, after which RNA-sequencing was used to identify convergent differentially expressed genes across treatments. Propranolol was found to affect the expression of genes previously associated with ET and other movement disorders such as TRAPPC11. Pathway enrichment analysis of these convergent drug-targeted genes identified multiple terms related to calcium signaling, endosomal sorting, axon guidance, and neuronal morphology. Furthermore, genes targeted by ET drugs were enriched within cell types having high expression of ET-related genes in both cortical and cerebellar tissues. Altogether, our results highlight potential cellular and molecular mechanisms associated with tremor reduction and identify relevant genetic biomarkers for drug-responsiveness in ET.

Predictors of stress in college students during the COVID-19 pandemic.

Background: College students experience high stress levels during emergency remote classes in the COVID-19 pandemic. However, it is not clear whether this is due to the summation effect of both stressors (classes and pandemic). Therefore, the aim of this study was to investigate predictors of stress in college students before and during remote classes five months after the beginning of the COVID-19 pandemic. Methods: The study was conducted before (BRC, July-August 2020) and during remote classes (DRC, October-November 2020). The sample consisted of 177 individuals (80 in BRC, 97 in DRC). Students were asked to self-collect saliva for cortisol analysis at each moment of the study, and to fill out a form to characterize the individual and assess the chronotype (Morningness-Eveningness Questionnaire), sleep quality (Pittsburgh Sleep Quality Index) and the stress (Perceived Stress Scale-10). Results: There was no difference between the evaluated periods for cortisol, perceived stress or sleep quality. Predictors for cortisol levels were gender, academic semester, chronotype, sleep quality and sadness due to pandemic (p<0.001). Limitations: Short interval between BRC and DRC assessments of perceived stress and salivary cortisol. Conclusions: Age, sex, income, academic semester, chronotype, and the impact of the pandemic on mood are predictors of stress among college students. In addition, emergency remote classes and sleep quality contribute to less stress.

Association of Essential Tremor With Novel Risk Loci: A Genome-Wide Association Study and Meta-analysis.

Importance: Essential tremor (ET) is one of the most common movement disorders, affecting 5% of the general population older than 65 years. Common variants are thought to contribute toward susceptibility to ET, but no variants have been robustly identified. Objective: To identify common genetic factors associated with risk of ET. Design, Setting, and Participants: Case-control genome-wide association study. Inverse-variance meta-analysis was used to combine cohorts. Multicenter samples collected from European populations were collected from January 2010 to September 2019 as part of an ongoing study. Included patients were clinically diagnosed with or reported having ET. Control individuals were not diagnosed with or reported to have ET. Of 485 250 individuals, data for 483 054 passed data quality control and were used. Main Outcomes and Measures: Genotypes of common variants associated with risk of ET. Results: Of the 483 054 individuals included, there were 7177 with ET (3693 [51.46%] female; mean [SD] age, 62.66 [15.12] years), and 475 877 control individuals (253 785 [53.33%] female; mean [SD] age, 56.40 [17.6] years). Five independent genome-wide significant loci and were identified and were associated with approximately 18% of ET heritability. Functional analyses found significant enrichment in the cerebellar hemisphere, cerebellum, and axonogenesis pathways. Genetic correlation (r), which measures the degree of genetic overlap, revealed significant common variant overlap with Parkinson disease (r, 0.28; P = 2.38 × 10-8) and depression (r, 0.12; P = 9.78 × 10-4). A separate fine-mapping of transcriptome-wide association hits identified genes such as BACE2, LRRN2, DHRS13, and LINC00323 in disease-relevant brain regions, such as the cerebellum. Conclusions and Relevance: The results of this genome-wide association study suggest that a portion of ET heritability can be explained by common genetic variation and can help identify new common genetic risk factors for ET.

Neuroimaging investigation of memory changes in migraine: a systematic review.

BACKGROUND: Individuals with migraine usually complain about lower memory performance. Diagnostic methods such as neuroimaging may help in the understanding of possible morphologic and functional changes related to the memory of those individuals. Therefore, the aim of this review is to analyze the available literature on neuroimaging changes related to memory processing in migraine. METHODS: We searched the following databases: Pubmed/Medline, Psycinfo, Science Direct, Cochrane and Web of Science. We used articles without restriction of year of publication. The combination of descriptors used for this systematic review of literature were Neuroimaging OR Imaging OR Brain AND Migraine OR Chronic Migraine AND Memory. RESULTS: Of the 306 articles found, nine were selected and all used magnetic resonance imaging (MRI). The studies used structural and functional MRI techniques with a predominance of 3 Tesla equipment and T1-weighted images. According to the results obtained reported by these studies, migraine would alter the activity of memory-related structures, such as the hippocampus, insula and frontal, parietal and temporal cortices, thereby suggesting a possible mechanism by which migraine would influence memory, especially in relation to the memory of pain. CONCLUSIONS: Migraine is associated to global dysfunction of multisensory integration and memory processing. This condition changes the activity of structures in various regions related to memory of pain, prospective memory, as well as in short- and long-term verbal and visuospatial memories. However, it is necessary to perform studies with larger samples in association with cognitive tests, and without the interference of medications to verify possible alterations and to draw more concrete conclusions.

Transcranial direct current stimulation in the modulation of neuropathic pain: a systematic review.

Objective To investigate the neuromodulating effect of Transcranial Direct Current Stimulation (tDCS) on Neuropathic Pain (NP). Method A systematic review of articles published in the past five years in MEDLINE, LILACS, Cochrane, Scopus, ScienceDirect, and PEDro. The search was carried out from February to May 2017 using the keywords: neuropathic pain, neuralgia, nerve pain, central pain, peripheral nerve pain, tDCS. The selected studies were full articles written in Portuguese, English, or Spanish with at least one control group, and no less than one pre- or post-intervention variable, with the exclusion of case studies or case series, animal model studies, and studies with combined therapy. The quality of the selected articles was evaluated through PEDro scale, whereas the level of agreement among reviewers was measured with the Cohen's κ test, considering P < 0.05 to be significant. Results Eight articles were selected (PEDro: 8.5 ± 0.6; Cohen's κ test: 0.703, P < 0.01), six of which were randomized controlled trials and two were controlled clinical trials. The following causes of NP were observed: spinal cord injury (SCI), amputation, stroke, multiple sclerosis (MS), and radiculopathy. All of the studies showed significant effects of tDCS on NP when compared to the control group, except for one with SCI and another related to radiculopathy. Discussion The shortage of good quality articles, the varying of ramp-on and ramp-off durations, and number of sessions, as well as the diversity of results found did not allow any definite conclusion on the efficacy of the neuromodulating effect of tDCS on NP.

Neuroimaging investigation of memory changes in migraine: a systematic review / Investigação por neuroimagem das alterações de memória na enxaqueca: uma revisão sistemática

ABSTRACT Background: Individuals with migraine usually complain about lower memory performance. Diagnostic methods such as neuroimaging may help in the understanding of possible morphologic and functional changes related to the memory of those individuals. Therefore, the aim of this review is to analyze the available literature on neuroimaging changes related to memory processing in migraine. Methods: We searched the following databases: Pubmed/Medline, Psycinfo, Science Direct, Cochrane and Web of Science. We used articles without restriction of year of publication. The combination of descriptors used for this systematic review of literature were Neuroimaging OR Imaging OR Brain AND Migraine OR Chronic Migraine AND Memory. Results: Of the 306 articles found, nine were selected and all used magnetic resonance imaging (MRI). The studies used structural and functional MRI techniques with a predominance of 3 Tesla equipment and T1-weighted images. According to the results obtained reported by these studies, migraine would alter the activity of memory-related structures, such as the hippocampus, insula and frontal, parietal and temporal cortices, thereby suggesting a possible mechanism by which migraine would influence memory, especially in relation to the memory of pain. Conclusions: Migraine is associated to global dysfunction of multisensory integration and memory processing. This condition changes the activity of structures in various regions related to memory of pain, prospective memory, as well as in short- and long-term verbal and visuospatial memories. However, it is necessary to perform studies with larger samples in association with cognitive tests, and without the interference of medications to verify possible alterations and to draw more concrete conclusions.

RESUMO Introdução: Indivíduos com enxaqueca geralmente se queixam de menor desempenho de memória. Métodos de diagnóstico como a neuroimagem podem auxiliar no entendimento de possíveis alterações morfológicas e funcionais relacionadas à memória desses indivíduos. Portanto, o objetivo desta revisão é analisar a literatura disponível sobre alterações de neuroimagem relacionadas a alterações de memória na enxaqueca. Métodos: Pesquisou-se nas seguintes bases de dados: PubMed/MEDLINE, Psycinfo, Science Direct, Cochrane e Web of Science. Foram utilizados artigos sem restrição de ano de publicação. A combinação dos descritores utilizados para esta revisão sistemática da literatura foram Neuroimaging OR Imaging OR Brain AND Migraine OR Chronic Migraine AND Memory. Resultados: Dos 306 artigos encontrados, nove foram selecionados e todos utilizaram ressonância magnética (RM). Os estudos utilizaram as técnicas de RM estrutural e funcional com predomínio de equipamentos de 3 Tesla e imagens ponderadas em T1. De acordo com os resultados obtidos nos estudos, a enxaqueca alteraria a atividade de estruturas relacionadas à memória, como o hipocampo, a ínsula e os córtices frontal, parietal e temporal, sugerindo um possível mecanismo pelo qual a enxaqueca influenciaria a memória, especialmente em relação à memória da dor. Conclusões: A enxaqueca está associada à disfunção global da integração multissensorial e processamento de memória. Essa condição altera a atividade de estruturas em várias regiões relacionadas à memória da dor, à memória prospectiva, bem como às memórias verbais e visuais-espaciais de curto e longo prazo. No entanto, é necessário realizar estudos com amostras maiores em associação com testes cognitivos, e sem a interferência de medicamentos para verificar possíveis alterações e tecer conclusões mais concretas.