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Journal of Neuroengineering and... Jun 2024Repeated transcranial magnetic stimulation (rTMS) could induce alterations in cortical excitability and promote neuroplasticity. To precisely quantify these effects,... (Meta-Analysis)
Meta-Analysis Review
Impact of repetitive transcranial magnetic stimulation on cortical activity: a systematic review and meta-analysis utilizing functional near-infrared spectroscopy evaluation.
BACKGROUND
Repeated transcranial magnetic stimulation (rTMS) could induce alterations in cortical excitability and promote neuroplasticity. To precisely quantify these effects, functional near-infrared spectroscopy (fNIRS), an optical neuroimaging modality adept at detecting changes in cortical hemodynamic responses, has been employed concurrently alongside rTMS to measure and tailor the impact of diverse rTMS protocols on the brain cortex.
OBJECTIVE
This systematic review and meta-analysis aimed to elucidate the effects of rTMS on cortical hemodynamic responses over the primary motor cortex (M1) as detected by fNIRS.
METHODS
Original articles that utilized rTMS to stimulate the M1 cortex in combination with fNIRS for the assessment of cortical activity were systematically searched across the PubMed, Embase, and Scopus databases. The search encompassed records from the inception of these databases up until April, 2024. The assessment for risk of bias was also conducted. A meta-analysis was also conducted in studies with extractable raw data.
RESULTS
Among 312 studies, 14 articles were eligible for qualitative review. 7 studies were eligible for meta-analysis. A variety of rTMS protocols was employed on M1 cortex. In inhibitory rTMS, multiple studies observed a reduction in the concentration of oxygenated hemoglobin [HbO] at the ipsilateral M1, contrasted by an elevation at the contralateral M1. Meta-analysis also corroborated this consistent trend. Nevertheless, certain investigations unveiled diminished [HbO] in bilateral M1. Several studies also depicted intricate inhibitory or excitatory interplay among distinct cortical regions.
CONCLUSION
Diverse rTMS protocols led to varied patterns of cortical activity detected by fNIRS. Meta-analysis revealed a trend of increasing [HbO] in the contralateral cortices and decreasing [HbO] in the ipsilateral cortices following low frequency inhibitory rTMS. However, due to the heterogeneity between studies, further research is necessary to comprehensively understand rTMS-induced alterations in brain activity.
Topics: Transcranial Magnetic Stimulation; Spectroscopy, Near-Infrared; Humans; Motor Cortex
PubMed: 38915003
DOI: 10.1186/s12984-024-01407-9 -
Frontiers in Neuroanatomy 2024Literature suggests a common pathophysiological ground between carotid atherosclerosis (CAS) and white matter alterations in the brain. However, the association between...
INTRODUCTION
Literature suggests a common pathophysiological ground between carotid atherosclerosis (CAS) and white matter alterations in the brain. However, the association between carotid intima-media thickness (CIMT) and white matter hyperintensities (WMH) has not been conclusively reported. The current systematic review explores and reports the relationship between CIMT and WMH among asymptomatic/non-stroke adults.
METHODS
A recent literature search on PubMed, SCOPUS, and Web of Science databases was conducted in compliance with the PRISMA protocol. The pre-defined Population-Intervention-Comparison-Outcome-Study (PICOS) criteria included observational studies investigating the CIMT-WMH association among non-stroke adults undergoing magnetic resonance imaging and carotid ultrasound.
RESULTS
Out of 255 potential results, 32 studies were critically assessed for selection, and finally, 10 articles were included, comprising 5,116 patients (females = 60.2%; males = 39.8%) aged between 36-71 years. The included studies earned high quality ratings (6-9) based on the Newcastle-Ottawa-Scale criteria. Qualitative synthesis showed a significantly parallel relationship between increased CIMT and greater WMH burden in 50% of the studies. In addition, significant risk factors related to the CIMT-WMH association included older age, hypertension, depression, migraine, Hispanic ethnicity, and apolipoprotein E (ɛ4) in postmenopausal women.
CONCLUSION
Overall, the cumulative evidence showed a consistent CIMT-WMH association in asymptomatic middle-aged and older non-stroke adults, indicating that CAS may contribute to the progression of pathologically hyperintense white matter in the brain. However, further research is warranted to infer the plausible relationship between CIMT and WMH in the absence of stroke.
PubMed: 38903057
DOI: 10.3389/fnana.2024.1394766 -
Clinical Neurophysiology : Official... Jul 2024Fibromyalgia Syndrome (FMS), Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Long COVID (LC) are similar multisymptom clinical syndromes but with... (Review)
Review
Fibromyalgia Syndrome (FMS), Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Long COVID (LC) are similar multisymptom clinical syndromes but with difference in dominant symptoms in each individual. There is existing and emerging literature on possible functional alterations of the central nervous system in these conditions. This review aims to synthesise and appraise the literature on resting-state quantitative EEG (qEEG) in FMS, ME/CFS and LC, drawing on previous research on FMS and ME/CFS to help understand neuropathophysiology of the new condition LC. A systematic search of MEDLINE, Embase, CINHAL, PsycINFO and Web of Science databases for articles published between December 1994 and September 2023 was performed. Out of the initial 2510 studies identified, 17 articles were retrieved that met all the predetermined selection criteria, particularly of assessing qEEG changes in one of the three conditions compared to healthy controls. All studies scored moderate to high quality on the Newcastle-Ottawa scale. There was a general trend for decreased low-frequency EEG band activity (delta, theta, and alpha) and increased high-frequency EEG beta activity in FMS, differing to that found in ME/CFS. The limited LC studies included in this review focused mainly on cognitive impairments and showed mixed findings not consistent with patterns observed in FMS and ME/CFS. Our findings suggest different patterns of qEEG brainwave activity in FMS and ME/CFS. Further research is required to explore whether there are phenotypes within LC that have EEG signatures similar to FMS or ME/CFS. This could inform identification of reliable diagnostic markers and possible targets for neuromodulation therapies tailored to each clinical syndrome.
Topics: Humans; Fatigue Syndrome, Chronic; Fibromyalgia; COVID-19; Electroencephalography; Brain
PubMed: 38772083
DOI: 10.1016/j.clinph.2024.04.019 -
Psychiatry and Clinical... Sep 2023Gray matter alterations play a role in the panic disorder's pathophysiology origin. However, the current literature seemed inadequate to reach a consistent conclusion....
BACKGROUND
Gray matter alterations play a role in the panic disorder's pathophysiology origin. However, the current literature seemed inadequate to reach a consistent conclusion. Therefore, we conducted this gray matter meta-analysis on panic disorder.
METHODS
A systematic review and a voxel-wise meta-analysis based on voxel-based morphometry were conducted for the gray matter studies in patients with panic disorder. The Seed-based d Mapping toolbox was applied for the voxel-wise meta-analysis. Fourteen gray matter studies (954 subjects) were enrolled in the current meta-analysis. The subgroup analysis of typical-onset versus late-onset patients was also performed. At last, the clinical severity was meta-regressed with gray matter alterations.
RESULTS
Significant gray matter alterations were found in the left para-cingulate gyrus and the right amygdala of panic disorder patients. The subgroup analysis of typical-onset panic disorder patients showed a similar pattern. However, gray matter alterations were demonstrated in the bilateral opercular cortex of late-onset panic disorder patients. A significant association between the clinical severity and the gray matter alterations was found in the fronto-cingulate regions of panic disorder patients.
CONCLUSION
Gray matter alterations might represent a significant pillar of panic disorder's neurobiology, especially for the amygdala, cingulate, and frontal regions. Future gray matter studies in panic disorder should be needed to reconfirm this pattern of gray matter alterations.
PubMed: 38765308
DOI: 10.5152/pcp.2023.23684 -
European Review For Medical and... Apr 2024Dysgeusia is characterized by a loss of taste perception, leading to malnutrition. This situation affects inflammatory conditions such as respiratory and neurological... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
Dysgeusia is characterized by a loss of taste perception, leading to malnutrition. This situation affects inflammatory conditions such as respiratory and neurological conditions, obesity, cancer, chemotherapy, aging, and many others. To date, there is not much information on the prevalence and risk of dysgeusia in an inflammatory condition; also, it is unclear which flavor is altered.
MATERIALS AND METHODS
We systematically searched three databases from January 2018 to January 2023. Participants were children, adults, or elderly persons with an inflammatory condition and evaluated taste loss. A random effects model was used for statistical analysis to calculate the pooled odds ratio with its corresponding 95.0% confidence interval to estimate the probability of taste alteration (dysgeusia) in an inflammatory condition.
RESULTS
The data allowed us to conduct a systematic review, including 63 original articles and 15 studies to perform the meta-analysis. The meta-analysis indicated a heterogenicity of 84.7% with an odds ratio of 3.25 (2.66-3.96), indicating a significant risk of Alzheimer's disease, SARS-CoV-2, chemotherapy, and rhinosinusitis.
CONCLUSIONS
Inflammatory conditions and taste alterations are linked. Dysgeusia is associated with a higher risk of malnutrition and poorer general health status, especially in vulnerable populations.
Topics: Humans; Inflammation; Dysgeusia; Taste Perception; COVID-19; Alzheimer Disease; Taste; Malnutrition; SARS-CoV-2
PubMed: 38708467
DOI: 10.26355/eurrev_202404_36024 -
Heliyon May 2024Current imaging advancements quantify the use of cardiovascular magnetic resonance (CMR) derived T1 and T2 tissue characterization as robust indicators for...
BACKGROUND
Current imaging advancements quantify the use of cardiovascular magnetic resonance (CMR) derived T1 and T2 tissue characterization as robust indicators for cardiomyopathies, but limited literature exists on its clinical application in Takotsubo syndrome (TTS). This systematic review evaluated the T1 and T2 parametric mapping to delineate the current diagnostic and prognostic CMR imaging outcomes in TTS.
METHODS
A comprehensive literature search until October 2023 was performed on ScienceDirect, PubMed, Web of Science, and Cochrane Library by two independent reviewers adhering to the PRISMA framework. The Newcastle-Ottawa Scale (NOS) was used to evaluate the methodological quality of studies.
RESULTS
Out of 198 results, 8 studies were included in this qualitative synthesis, accounting for a total population of 399 subjects (TTS = 201, controls = 175, acute myocarditis = 14, and acute regional myocardial oedema without infarction = 9). Approximately 50.4 % were TTS patients aged between 61 and 73 years, whereof, females (n = 181, 90.0 %) and apical variants (n = 180, 89.6 %) were significantly higher, and emotional stressor (n = 42; 20.9 %) was more prevalent than physical (n = 27; 13.4 %). The NOS identified 62.5 % of studies as moderate and 37.5 % as high quality. Parametric tissue mapping revealed significantly prolonged T1 and T2 relaxation times at 1.5T and 3T respectively in TTS (1053-1164 msec, 1292-1438 msec; and 56-67 msec, 60-90 msec) with higher extracellular volume (ECV) fraction (29-36 %), compared to healthy subjects (944-1211 msec, 1189-1251 msec; and 46-54 msec, 32-68 msec; 23-29 %) and myocarditis (1058 msec, 60 msec). Other significant myocardial abnormalities included increased left ventricular (LV) end-systolic and diastolic volume and reduced global longitudinal strain. Overall, myocardial oedema, altered LV mass and strain, and worse LV systolic function, with higher native T1, T2, and ECV values were consistent.
CONCLUSIONS
Future research with substantially larger clinical trials is vital to explore the CMR imaging findings in diverse TTS patient cohorts and correlate the T1 and T2 mapping outcomes with demographic/clinical covariates. CMR is a valuable imaging tool for TTS diagnosis and prognostication. T1 and T2 parametric mapping facilitates the quantification of oedema, inflammation, and myocardial injury in Takotsubo.
PubMed: 38707280
DOI: 10.1016/j.heliyon.2024.e29755 -
The Ocular Surface Jul 2024Corneal neuropathy involves corneal nerve damage that disrupts ocular surface integrity, negatively impacting quality-of-life from pain and impaired vision. Any ocular... (Review)
Review
Corneal neuropathy involves corneal nerve damage that disrupts ocular surface integrity, negatively impacting quality-of-life from pain and impaired vision. Any ocular or systemic condition that damages the trigeminal nerve can lead to corneal neuropathy. However, the condition currently does not have standardized diagnostic criteria or treatment protocols. The primary aim of this systematic review was to evaluate the efficacy and safety of interventions for treating corneal neuropathy. Randomized controlled trials (RCTs) that investigated corneal neuropathy treatments were eligible if the intervention(s) was compared to a placebo or active comparator. Comprehensive searches were conducted in Ovid MEDLINE, Ovid Embase and clinical trial registries from inception to July 2022. The Cochrane Risk-of-Bias 2 tool was used to assess study methodological quality. Certainty of the body of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Overall, 20 RCTs were included. Evaluated interventions comprised regenerative therapies (n = 6 studies), dietary supplements (n = 4), anti-glycemic agents (n = 3), combination therapy (n = 3), supportive therapies (n = 2) and systemic pain pharmacotherapies (n = 2). Nine RCTs were judged at high risk of bias for most outcomes. Definitions for corneal neuropathy in the populations varied substantially across studies, consistent with lack of consensus on diagnostic criteria. A diverse range of outcomes were quantified, likely reflecting absence of an agreed core outcome set. There was insufficient evidence to draw definitive conclusions on the efficacy or safety of any intervention. There was low or very low certainty evidence for several neuroregenerative agents and dietary supplements for improving corneal nerve fiber length in corneal neuropathy due to dry eye disease and diabetes. Low or very low certainty evidence was found for neuroregenerative therapies and dietary supplements not altering corneal immune cell density. This review identifies a need to standardize the clinical definition of corneal neuropathy and define a minimum set of core outcome measures. Together, this will provide a foundation for improved phenotyping of clinical populations in studies, and improve the capacity to synthesize data to inform evidence-based care. Protocol registration: PROSPERO ID: CRD42022348475.
Topics: Humans; Cornea; Corneal Diseases; Randomized Controlled Trials as Topic; Trigeminal Nerve Diseases; Quality of Life
PubMed: 38688453
DOI: 10.1016/j.jtos.2024.04.004 -
The subcortical default mode network and Alzheimer's disease: a systematic review and meta-analysis.Brain Communications 2024The default mode network is a central cortical brain network suggested to play a major role in several disorders and to be particularly vulnerable to the...
The default mode network is a central cortical brain network suggested to play a major role in several disorders and to be particularly vulnerable to the neuropathological hallmarks of Alzheimer's disease. Subcortical involvement in the default mode network and its alteration in Alzheimer's disease remains largely unknown. We performed a systematic review, meta-analysis and empirical validation of the subcortical default mode network in healthy adults, combined with a systematic review, meta-analysis and network analysis of the involvement of subcortical default mode areas in Alzheimer's disease. Our results show that, besides the well-known cortical default mode network brain regions, the default mode network consistently includes subcortical regions, namely the thalamus, lobule and vermis IX and right Crus I/II of the cerebellum and the amygdala. Network analysis also suggests the involvement of the caudate nucleus. In Alzheimer's disease, we observed a left-lateralized cluster of decrease in functional connectivity which covered the medial temporal lobe and amygdala and showed overlap with the default mode network in a portion covering parts of the left anterior hippocampus and left amygdala. We also found an increase in functional connectivity in the right anterior insula. These results confirm the consistency of subcortical contributions to the default mode network in healthy adults and highlight the relevance of the subcortical default mode network alteration in Alzheimer's disease.
PubMed: 38665961
DOI: 10.1093/braincomms/fcae128 -
Schizophrenia Research May 2024Motor and cognitive alterations in schizophrenia-spectrum disorders (SSD) share common neural underpinnings, highlighting the necessity for a thorough exploration of the... (Review)
Review
Motor and cognitive alterations in schizophrenia-spectrum disorders (SSD) share common neural underpinnings, highlighting the necessity for a thorough exploration of the connections between these areas. This relationship is crucial, as it holds potential significance in unraveling the underlying mechanisms of SSD pathophysiology, ultimately leading to advancements in clinical staging and treatment strategies. The purpose of this review was to characterize the relationship between different hyper and hypokinetic domains of motor alterations and cognition in SSD. We systematically searched the literature (PROSPERO protocol CRD42019145964) and selected 66 original scientific contributions for review, published between 1987 and 2022. A narrative synthesis of the results was conducted. Hyper and hypokinetic motor alterations showed weak to moderate negative correlations with cognitive function across different SSD stages, including before antipsychotic treatment. The literature to date shows a diverse set of methodologies and composite cognitive scores hampering a strong conclusion about which specific cognitive domains were more linked to each group of motor alterations. However, executive functions seemed the domain more consistently associated with parkinsonism with the results regarding dyskinesia being less clear. Akathisia and catatonia were scarcely discussed in the reviewed literature. The present review reinforces the intimate relationship between specific motor alterations and cognition. Identified gaps in the literature challenge the formulation of definitive conclusions. Nevertheless, a discussion of putative underlying mechanisms is included, prompting guidance for future research endeavors.
Topics: Humans; Schizophrenia; Cognitive Dysfunction; Executive Function
PubMed: 38640851
DOI: 10.1016/j.schres.2024.04.014 -
Neural Regeneration Research Dec 2024The search for reliable and easily accessible biomarkers in Parkinson's disease is receiving a growing emphasis, to detect neurodegeneration from the prodromal phase and...
The search for reliable and easily accessible biomarkers in Parkinson's disease is receiving a growing emphasis, to detect neurodegeneration from the prodromal phase and to enforce disease-modifying therapies. Despite the need for non-invasively accessible biomarkers, the majority of the studies have pointed to cerebrospinal fluid or peripheral biopsies biomarkers, which require invasive collection procedures. Saliva represents an easily accessible biofluid and an incredibly wide source of molecular biomarkers. In the present study, after presenting the morphological and biological bases for looking at saliva in the search of biomarkers for Parkinson's disease, we systematically reviewed the results achieved so far in the saliva of different cohorts of Parkinson's disease patients. A comprehensive literature search on PubMed and SCOPUS led to the discovery of 289 articles. After screening and exclusion, 34 relevant articles were derived for systematic review. Alpha-synuclein, the histopathological hallmark of Parkinson's disease, has been the most investigated Parkinson's disease biomarker in saliva, with oligomeric alpha-synuclein consistently found increased in Parkinson's disease patients in comparison to healthy controls, while conflicting results have been reported regarding the levels of total alpha-synuclein and phosphorylated alpha-synuclein, and few studies described an increased oligomeric alpha-synuclein/total alpha-synuclein ratio in Parkinson's disease. Beyond alpha-synuclein, other biomarkers targeting different molecular pathways have been explored in the saliva of Parkinson's disease patients: total tau, phosphorylated tau, amyloid-β1-42 (pathological protein aggregation biomarkers); DJ-1, heme-oxygenase-1, metabolites (altered energy homeostasis biomarkers); MAPLC-3beta (aberrant proteostasis biomarker); cortisol, tumor necrosis factor-alpha (inflammation biomarkers); DNA methylation, miRNA (DNA/RNA defects biomarkers); acetylcholinesterase activity (synaptic and neuronal network dysfunction biomarkers); Raman spectra, proteome, and caffeine. Despite a few studies investigating biomarkers targeting molecular pathways different from alpha-synuclein in Parkinson's disease, these results should be replicated and observed in studies on larger cohorts, considering the potential role of these biomarkers in determining the molecular variance among Parkinson's disease subtypes. Although the need for standardization in sample collection and processing, salivary-based biomarkers studies have reported encouraging results, calling for large-scale longitudinal studies and multicentric assessments, given the great molecular potentials and the non-invasive accessibility of saliva.
PubMed: 38595280
DOI: 10.4103/NRR.NRR-D-23-01677