The latest medical research on Neurodegenerative Disorders

The research magnet gathers the latest research from around the web, based on your specialty area. Below you will find a sample of some of the most recent articles from reputable medical journals about neurodegenerative disorders gathered by our medical AI research bot.

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Deciphering Cognitive Impairments in Huntington's Disease: A Comparative Study of Stroop Test Variations.

Journal of Huntingtons Disease

Huntington's disease (HD) is a neurodegenerative disorder marked by cognitive impairment, movement abnormalities, and behavioral disturbances. The Stroop Color Word Test (SCWT) is a widely used tool to detect cognitive decline in HD. Variations in SCWT formats-horizontal (original) and vertical (Golden)-may influence performance, given HD's impact on cognitive and oculomotor abilities.

This study aimed to compare the effectiveness of the horizontal and Golden vertical SCWT formats in detecting cognitive decline in HD, and to determine how performance may have been influenced by eye movement abnormalities.

Forty-five participants with genetically confirmed HD were recruited. Both SCWT formats were administered to each participant in a counterbalanced fashion. Individual performance of all three sections on each format was standardized across 2 different norms. Raw and normed scores on each variation were compared and correlated with eye movement ratings on the Unified Huntington's Disease Rating Scale.

The Golden variation elicited significantly slower responses, particularly in the Word Reading section, across two benchmark norms. Statistical analysis revealed significant performance differences between the two formats. Correlations between vertical eye movement ratings and performance on the Golden SCWT were highly significant, highlighting the impact of oculomotor coordination on cognitive assessments in HD.

This study underscores the importance of considering test format in cognitive assessments for HD. The Golden vertical SCWT demonstrates increased sensitivity in detecting deficits in HD, possibly linked to vertical saccade abnormalities. These insights are important for improving the sensitivity of cognitive assessments and monitoring disease progression in HD research and clinical practice.

Cognitive rehabilitation effects on grey matter volume and Go-NoGo activity in progressive multiple sclerosis: results from the CogEx trial.

Neurology, Neurosurgery and Psychiatry

NCT03679468.

Participants were randomised to: 'CR plus EX', 'CR plus sham EX (EX-S)', 'EX plus sham CR (CR-S)' and 'CR-S plus EX-S' and attended 12-week intervention. All subjects performed physical/cognitive assessments at baseline, week 12 and 6 months post intervention (month 9). All MRI substudy participants underwent volumetric MRI and fMRI (Go-NoGo task).

104 PMS enrolled at four sites participated in the CogEx MRI substudy; 84 (81%) had valid volumetric MRI and valid fMRI. Week 12/month 9 cognitive performances did not differ among interventions; however, 25-62% of the patients showed Symbol Digit Modalities Test improvements. Normalised cortical grey matter volume (NcGMV) changes at week 12 versus baseline were heterogeneous among interventions (p=0.05); this was mainly driven by increased NcGMV in 'CR plus EX-S' (p=0.02). Groups performing CR (ie, 'CR plus EX' and 'CR plus EX-S') exhibited increased NcGMV over time, especially in the frontal (p=0.01), parietal (p=0.04) and temporal (p=0.04) lobes, while those performing CR-S exhibited NcGMV decrease (p=0.008). In CR groups, increased NcGMV (r=0.36, p=0.01) at week 12 versus baseline correlated with increased California Verbal Learning Test (CVLT)-II scores. 'CR plus EX-S' patients exhibited Go-NoGo activity increase (p<0.05, corrected) at week 12 versus baseline in bilateral insula.

In PMS, CR modulated grey matter (GM) volume and insular activity. The association of GM and CVLT-II changes suggests GM plasticity contributes to cognitive improvements.

Relationship Between the Gut Microbiota and Neurological Deficits in Patients With Cerebral Ischemic Stroke.

Neurorehabilitation and Neural Repair

The aim of the paper was to investigate the composition and structure of intestinal flora in patients with cerebral ischemic stroke (CIS), and to investigate the relationship between gut microbiota (GM) and different levels of stroke severity.

In this study, 47 CIS patients (16 mild, 21 moderate, and 10 severe) and 15 healthy controls were included. General information, clinical data, and behavioral scores of the enrolled subjects were collected. Deoxyribonucleic acid in fecal intestinal flora was extracted and detected using high-throughput Illumina 16S ribosomal ribonucleic acid sequencing technology. Finally, the correlation between the community composition of intestinal microbiota and National Institutes of Health Stroke Scale (NIHSS) score in CIS patients was analyzed.

Compared with healthy controls, there was no statistically significant difference in Alpha diversity among CIS patients, but the principal coordinate analysis showed significant differences in the composition of the GM among stroke patients with different degrees of severity and controls. In CIS patients, Streptococcus was significantly enriched, and Eshibacter-Shigella, Bacteroides, and Agathobacter were significantly down-regulated (P < .05). In addition, the relative abundance of Blautia was negatively correlated with the NIHSS score.

Our results show that different degrees of CIS severity exert distinct effects on the intestinal microbiome. This study reveals the intestinal microecological changes after brain injury from the perspective of brain-gut axis. Intestinal microorganisms not only reveal the possible pathological process and indicate the severity of neurologic impairment, but also make targeted therapy possible for CIS patients.

Alzheimer blood biomarkers: practical guidelines for study design, sample collection, processing, biobanking, measurement and result reporting.

Molecular Neurodegeneration

Alzheimer's disease (AD), the most common form of dementia, remains challenging to understand and treat despite decades of research and clinical in...

Gut Microbiota as a Modifier of Huntington's Disease Pathogenesis.

Journal of Huntingtons Disease

Huntingtin (HTT) protein is expressed in most cell lineages, and the toxicity of mutant HTT in multiple organs may contribute to the neurological a...

The Priority Goals and Underlying Impairments Contributing to Goal-Related Problems of People with Parkinson's Disease Receiving a Community-Based Rehabilitation Program.

Parkinsons Disease

Goal setting is a core rehabilitation practice in Parkinson's disease (PD). Targeting therapy towards specific goals leads to greater improvements in performance and psychosocial outcomes. Goal setting in PD is feasible, and although the nature of goals has been described in previous studies, the underlying impairments related to goals have not been described. Understanding the nature of goals ensures that interventions for people with PD are aligned with their needs and priorities. Understanding the underlying impairments highlights which symptoms have the biggest impact on daily life and is necessary for planning appropriate interventions to target them.

To describe the nature of the goals of people with PD; the underlying impairments related to goals; and to compare differences between high and low priority goals.

Deductive content analysis was used to map goal statements to the international classification of function (ICF) activity and participation category and to map therapist field notes detailing the primary underlying impairment to the ICF Body Functions category. These results were then compared across goal priority rankings.

88 goals of 22 people with PD were analysed. We found that people with PD set diverse goals across all chapters of the ICF Activity and Participation category, with "self-care" goals making up the highest proportion of goals. The primary underlying impairment related to the goals was predominantly related to impairments in "mental functions" under the Body Functions category. Regardless of goal priority, most goal-related underlying impairments were found to be in the "mental functions" category.

The goals of this sample of community-dwelling people with PD highlight their diverse needs and priorities. These findings indicate that nonmotor symptoms, namely, executive dysfunction and amotivation most commonly impact the performance of and participation in activities of greatest importance to people with PD. This trial is registered with ACTRN12621001483842.

Characterization of an Algorithm for Autonomous, Closed-Loop Neuromodulation During Motor Rehabilitation.

Neurorehabilitation and Neural Repair

Recent evidence demonstrates that manually triggered vagus nerve stimulation (VNS) combined with rehabilitation leads to increased recovery of upper limb motor function after stroke. This approach is premised on studies demonstrating that the timing of stimulation relative to movements is a key determinant in the effectiveness of this approach.

The overall goal of the study was to identify an algorithm that could be used to automatically trigger VNS on the best movements during rehabilitative exercises while maintaining a desired interval between stimulations to reduce the burden of manual stimulation triggering.

To develop the algorithm, we analyzed movement data collected from patients with a history of neurological injury. We applied 3 different algorithms to the signal, analyzed their triggering choices, and then validated the best algorithm by comparing triggering choices to those selected by a therapist delivering VNS therapy.

The dynamic algorithm triggered above the 95th percentile of maximum movement at a rate of 5.09 (interquartile range [IQR] = 0.74) triggers per minute. The periodic algorithm produces stimulation at set intervals but low movement selectivity (34.05%, IQR = 7.47), while the static threshold algorithm produces long interstimulus intervals (27.16 ± 2.01 seconds) with selectivity of 64.49% (IQR = 25.38). On average, the dynamic algorithm selects movements that are 54 ± 3% larger than therapist-selected movements.

This study shows that a dynamic algorithm is an effective strategy to trigger VNS during the best movements at a reliable triggering rate.

Presence of Self-Reported Sleep Alterations After Stroke and Their Relationship With Disability: A Longitudinal Study.

Neurorehabilitation and Neural Repair

Sleep disorders have a prevalence of 30% to 70% in post-stroke individuals. The presence of sleep disorders and poor sleep quality after stroke can affect important functions and lead to worse outcomes. However, most studies are restricted to the acute post-stroke stage only.

To investigate the frequency of self-reported sleep alterations in a sample of chronic stroke individuals and to identify which self-reported sleep alterations were associated with disability.

Prospective exploratory study. Self-reported sleep alterations were measured by the Pittsburgh Sleep Quality Index, Insomnia Severity Index, Epworth Sleepiness Scale, and STOP-Bang Questionnaire. The dependent variable was measured 3 years after the first contact by the Modified Rankin Scale (mRS). Step-wise multiple linear regression analysis was employed to identify which sleep alterations were associated with disability.

Sixty-five individuals with stroke participated. About 67.7% of participants had poor sleep quality, 52.4% reported insomnia symptoms, 33.9% reported excessive daytime sleepiness, and 80.0% were classified as intermediate or high risk for obstructive sleep apnea. Only risk for obstructive sleep apnea was significantly associated with disability and explained 5% of the variance in the mRS scores.

Self-reported sleep alterations had a considerable frequency in a sample of chronic stroke individuals. The risk of obstructive sleep apnea was associated with disability in the chronic stage of stroke. Sleep alterations must be considered and evaluated in the rehabilitation process even after a long period since the stroke onset.

What Huntington's Disease Patients Say About Their Illness: An Online Direct-to-Participant Pilot Study.

Journal of Huntingtons Disease

Direct-to-participant online reporting facilitates the conduct of clinical research by increasing access and clinically meaningful patient engagement.

We assessed feasibility of online data collection from adults with diagnosed Huntington's disease (HD) who directly reported their problems and impact in their own words.

Data were collected online from consenting United States residents who self-identified as 1) having been diagnosed with Huntington's disease, 2) able to ambulate independently, and 3) self-sufficient for most daily needs. Data for this pilot study were collected using the Huntington Study Group myHDstory online research platform. The Huntington Disease Patient Report of Problems (HD-PROP), an open-ended questionnaire, was used to capture verbatim bothersome problems and functional impact. Natural language processing, human-in-the-loop curation of verbatim reports involving clinical and experience experts, and machine learning classified verbatim-reports into clinically meaningful symptoms.

All 8 questionnaires in the online pilot study were completed by 345 participants who were 60.9% men, 34.5±9.9 (mean±SD) years old, and 9.5±8.4 years since HD diagnosis. Racial self-identification was 46.4% Caucasian, 28.7% African American, 15.4% American Indian/Alaska Native, and 9.5% other. Accuracy of verbatim classification was 99%. Non-motor problems were the most frequently reported symptoms; depression and cognitive impairment were the most common.

Online research participation was feasible for a diverse cohort of adults who self-reported an HD diagnosis and predominantly non-motor symptoms related to mood and cognition. Online research tools can help inform what bothers HD patients, identify clinically meaningful outcomes, and facilitate participation by diverse and under-represented populations.

Effectiveness of Motor Imagery in the Rehabilitation of People With Parkinson's Disease: A Systematic Review and Meta-Analysis.

Neurorehabilitation and Neural Repair

With more research completed using Motor imagery (MI) in people with Parkinson's disease, this study gathered and synthesized evidence on the use of MI for Parkinson's disease in improving rehabilitation outcomes.

Medical Literature Analysis and Retrieval System Online, Embase, Web of Science, The Cochrane Library, PsycINFO, Cumulative Index to Nursing and Allied Health Literature, and Scopus were searched from inception to May 2023. We included randomized controlled trials that examine the effects of MI on individuals with Parkinson's disease. Two reviewers selected articles and extracted study characteristics and results independently. The Physiotherapy Evidence Database scale was used to assess the methodological quality. Mean differences and 95% confidence intervals were calculated. Heterogeneity was assessed using the I2 statistic.

Thirteen articles with 12 studies were included, involving 320 individuals with Parkinson's disease, with moderate to high methodological quality (mean = 6.62/10). Compared with the control group, 3 articles reported significant greater improvements in cognitive function, 7 reported significant greater improvement in motor function, 1 article reported significant greater improvement in quality of life, and 1 reported significant greater confidence in daily task performance. No statistically significant effects were found in the meta-analyses. Conclusion. Results of individual articles were in favor of the MI intervention. No statistically significant results were found in the meta-analyses. This might be due to the small number of studies and the heterogeneity of interventions and outcome measures used. MI may be effective in improving some rehabilitation outcomes, but meta-analytic evidence is lacking. More research with larger sample size and less heterogeneous samples, interventions, and outcome measures, is warranted.

PROSPERO registration number CRD42021230556.

Exploring the Structural Plasticity Mechanism of Corticospinal Tract during Stroke Rehabilitation Based Automated Fiber Quantification Tractography.

Neurorehabilitation and Neural Repair

Corticospinal tract (CST) is the principal motor pathway; we aim to explore the structural plasticity mechanism in CST during stroke rehabilitation.

A total of 25 patients underwent diffusion tensor imaging before rehabilitation (T1), 1-month post-rehabilitation (T2), 2 months post-rehabilitation (T3), and 1-year post-discharge (T4). The CST was segmented, and fractional anisotropy (FA), axial diffusion (AD), mean diffusivity (MD), and radial diffusivity (RD) were determined using automated fiber quantification tractography. Baseline level of laterality index (LI) and motor function for correlation analysis.

The FA values of all segments in the ipsilesional CST (IL-CST) were lower compared with normal CST. Repeated measures analysis of variance showed time-related effects on FA, AD, and MD of the IL-CST, and there were similar dynamic trends in these 3 parameters. At T1, FA, AD, and MD values of the mid-upper segments of IL-CST (around the core lesions) were the lowest; at T2 and T3, values for the mid-lower segments were lower than those at T1, while the values for the mid-upper segments gradually increased; at T4, the values for almost entire IL-CST were higher than before. The highest LI was observed at T2, with a predominance in contralesional CST. The LIs for the FA and AD at T1 were positively correlated with the change rate of motor function.

IL-CST showed aggravation followed by improvement from around the lesion to the distal end. Balance of interhemispheric CST may be closely related to motor function, and LIs for FA and AD may have predictive value for mild-to-moderate stroke rehabilitation. Clinical Trial Registration. URL: http://www.chictr.org.cn; Unique Identifier: ChiCTR1800019474.

Clinical Review of Juvenile Huntington's Disease.

Journal of Huntingtons Disease

 Juvenile Huntington's disease (JHD) is rare. In the first decade of life speech difficulties, rigidity, and dystonia are common clinical motor sym...