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Frontiers in Immunology 2024Recent evidence supports the contribution of gut microbiota dysbiosis to the pathophysiology of rheumatic diseases, neuropathic pain, and neurodegenerative disorders.... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
Recent evidence supports the contribution of gut microbiota dysbiosis to the pathophysiology of rheumatic diseases, neuropathic pain, and neurodegenerative disorders. The bidirectional gut-brain communication network and the occurrence of chronic pain both involve contributions of the autonomic nervous system and the hypothalamic pituitary adrenal axis. Nevertheless, the current understanding of the association between gut microbiota and chronic pain is still not clear. Therefore, the aim of this study is to systematically evaluate the existing knowledge about gut microbiota alterations in chronic pain conditions.
METHODS
Four databases were consulted for this systematic literature review: PubMed, Web of Science, Scopus, and Embase. The Newcastle-Ottawa Scale was used to assess the risk of bias. The study protocol was prospectively registered at the International prospective register of systematic reviews (PROSPERO, CRD42023430115). Alpha-diversity, β-diversity, and relative abundance at different taxonomic levels were summarized qualitatively, and quantitatively if possible.
RESULTS
The initial database search identified a total of 3544 unique studies, of which 21 studies were eventually included in the systematic review and 11 in the meta-analysis. Decreases in alpha-diversity were revealed in chronic pain patients compared to controls for several metrics: observed species (SMD= -0.201, 95% CI from -0.04 to -0.36, p=0.01), Shannon index (SMD= -0.27, 95% CI from -0.11 to -0.43, p<0.001), and faith phylogenetic diversity (SMD -0.35, 95% CI from -0.08 to -0.61, p=0.01). Inconsistent results were revealed for beta-diversity. A decrease in the relative abundance of the Lachnospiraceae family, genus and , and species of and , as well as an increase in spp., was revealed in chronic pain patients compared to controls.
DISCUSSION
Indications for gut microbiota dysbiosis were revealed in chronic pain patients, with non-specific disease alterations of microbes.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/, identifier CRD42023430115.
Topics: Humans; Chronic Pain; Dysbiosis; Hypothalamo-Hypophyseal System; Phylogeny; Pituitary-Adrenal System; Clostridiales
PubMed: 38352865
DOI: 10.3389/fimmu.2024.1342833 -
Neurosurgical Review Sep 2023Cingulate gyrus gliomas are rare among adult, hemispheric diffuse gliomas. Surgical reports are scarce. We performed a systematic review of the literature and... (Meta-Analysis)
Meta-Analysis Review
Cingulate gyrus gliomas are rare among adult, hemispheric diffuse gliomas. Surgical reports are scarce. We performed a systematic review of the literature and meta-analysis, with the aim of focusing on the extent of resection (EOR), WHO grade, and morbidity and mortality, after microsurgical resection of gliomas of the cingulate gyrus. Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we reviewed articles published between January 1996 and December 2022 and referenced in PubMed or Embase. Inclusion criteria were peer-reviewed clinical studies of microsurgical series reporting resection of gliomas of the cingulate gyrus. Primary outcome was EOR, classified as gross total (GTR) versus subtotal (STR) resection. Five studies reporting 295 patients were included. Overall GTR was 79.4% (range 64.1-94.7; I= 88.13; p heterogeneity and p < 0.001), while STR was done in 20.6% (range 5.3-35.9; I= 88.13; p heterogeneity < 0.001 and p= 0.008). The most common WHO grade was II, with an overall rate of 42.7% (24-61.5; I= 90.9; p heterogeneity, p< 0.001). Postoperative SMA syndrome was seen in 18.6% of patients (10.4-26.8; I2= 70.8; p heterogeneity= 0.008, p< 0.001), postoperative motor deficit in 11% (3.9-18; I= 18; p heterogeneity= 0.003, p= 0.002). This review found that while a GTR was achieved in a high number of patients with a cingulate glioma, nearly half of such patients have a postoperative deficit. This finding calls for a cautious approach in recommending and doing surgery for patients with cingulate gliomas and for consideration of new surgical and management approaches.
Topics: Adult; Humans; Gyrus Cinguli; Glioma; Postoperative Period; Syndrome
PubMed: 37656287
DOI: 10.1007/s10143-023-02127-9 -
Neuroscience and Biobehavioral Reviews Sep 2023Neural adaptations to resistance training (RT) and their correlation with muscle strength remain partially understood. We conducted a systematic review and multivariate... (Meta-Analysis)
Meta-Analysis Review
Neural adaptations to resistance training (RT) and their correlation with muscle strength remain partially understood. We conducted a systematic review and multivariate meta-analysis to examine the effects of metronome-paced (MP), self-paced (SP), and isometric (IM) training on M1 and corticospinal pathway activity. Following MP RT, a significant increase in corticospinal excitability was observed, correlating with increased strength. Conversely, no significant relationship was found after SP or IM training. RT also reduced the duration of the cortical silent period, but this change did not predict strength changes and was not specific to any training modality. No significant effects were found for short-interval intracortical inhibition. Our findings suggest that changes in corticospinal excitability may contribute to strength gains after RT. Furthermore, the relationship between these adaptations and strength appears dependent on the type of training performed.
Topics: Humans; Resistance Training; Pyramidal Tracts; Transcranial Magnetic Stimulation; Motor Cortex; Muscle Strength; Evoked Potentials, Motor; Muscle, Skeletal
PubMed: 37353049
DOI: 10.1016/j.neubiorev.2023.105289 -
Cognitive, Affective & Behavioral... Feb 2024All experiences preserved within episodic memory contain information on the space and time of events. The hippocampus is the main brain region involved in processing... (Meta-Analysis)
Meta-Analysis Review
All experiences preserved within episodic memory contain information on the space and time of events. The hippocampus is the main brain region involved in processing spatial and temporal information for incorporation within episodic memory representations. However, the other brain regions involved in the encoding and retrieval of spatial and temporal information within episodic memory are unclear, because a systematic review of related studies is lacking and the findings are scattered. The present study was designed to integrate the results of functional magnetic resonance imaging and positron emission tomography studies by means of a systematic review and meta-analysis to provide converging evidence. In particular, we focused on identifying the brain regions involved in the retrieval of spatial and temporal information. We identified a spatial retrieval network consisting of the inferior temporal gyrus, parahippocampal gyrus, superior parietal lobule, angular gyrus, and precuneus. Temporal context retrieval was supported by the dorsolateral prefrontal cortex. Thus, the retrieval of spatial and temporal information is supported by different brain regions, highlighting their different natures within episodic memory.
Topics: Humans; Memory, Episodic; Brain Mapping; Brain; Temporal Lobe; Parietal Lobe; Magnetic Resonance Imaging; Mental Recall
PubMed: 38030912
DOI: 10.3758/s13415-023-01140-1 -
Behavioural Neurology 2023Risk of suicidal ideation and suicidal behaviors greatly increases during adolescence, and rates have risen dramatically over the past two decades. However, few risk... (Review)
Review
INTRODUCTION
Risk of suicidal ideation and suicidal behaviors greatly increases during adolescence, and rates have risen dramatically over the past two decades. However, few risk factors or biomarkers predictive of suicidal ideation or attempted suicide have been identified in adolescents. Neuroimaging correlates hold potential for early identification of adolescents at increased risk of suicidality and risk stratification for those at high risk of suicide attempt.
METHODS
In this systematic review, we evaluated neural regions and networks associated with suicidal ideation and suicide attempt in adolescents derived from magnetic resonance imaging (MRI) studies. A total of 28 articles were included in this review.
RESULTS
After descriptively synthesizing the literature, we propose the Emotional paiN and social Disconnect (END) model of adolescent suicidality and present two key neural circuits: (1) the emotional/mental pain circuit and (2) the social disconnect/distortion circuit. In the END model, the emotional pain circuit-consisting of the cerebellum, amygdala, and hippocampus-shows similar aberrations in adolescents with suicidal ideation as in those with a history of a suicide attempt (but to a smaller degree). The social disconnect circuit is unique to adolescent suicide attempters and includes the lateral orbitofrontal cortex (OFC), the temporal gyri, and the connections between them.
CONCLUSION
Our proposed END brain model of suicidal behavior in youth, if confirmed by future prospective studies, can have implications for clinical goals of early detection, risk stratification, and intervention development. Treatments that target emotional pain and social disconnect may be ideal interventions for reducing suicidality in adolescents.
Topics: Humans; Adolescent; Suicidal Ideation; Prospective Studies; Magnetic Resonance Imaging; Risk Factors; Amygdala; Pain
PubMed: 37786433
DOI: 10.1155/2023/7254574 -
Molecular Psychiatry Oct 2023Aberrant anatomical brain connections in attention-deficit/hyperactivity disorder (ADHD) are reported inconsistently across diffusion weighted imaging (DWI) studies.... (Meta-Analysis)
Meta-Analysis
Aberrant anatomical brain connections in attention-deficit/hyperactivity disorder (ADHD) are reported inconsistently across diffusion weighted imaging (DWI) studies. Based on a pre-registered protocol (Prospero: CRD42021259192), we searched PubMed, Ovid, and Web of Knowledge until 26/03/2022 to conduct a systematic review of DWI studies. We performed a quality assessment based on imaging acquisition, preprocessing, and analysis. Using signed differential mapping, we meta-analyzed a subset of the retrieved studies amenable to quantitative evidence synthesis, i.e., tract-based spatial statistics (TBSS) studies, in individuals of any age and, separately, in children, adults, and high-quality datasets. Finally, we conducted meta-regressions to test the effect of age, sex, and medication-naïvety. We included 129 studies (6739 ADHD participants and 6476 controls), of which 25 TBSS studies provided peak coordinates for case-control differences in fractional anisotropy (FA)(32 datasets) and 18 in mean diffusivity (MD)(23 datasets). The systematic review highlighted white matter alterations (especially reduced FA) in projection, commissural and association pathways of individuals with ADHD, which were associated with symptom severity and cognitive deficits. The meta-analysis showed a consistent reduced FA in the splenium and body of the corpus callosum, extending to the cingulum. Lower FA was related to older age, and case-control differences did not survive in the pediatric meta-analysis. About 68% of studies were of low quality, mainly due to acquisitions with non-isotropic voxels or lack of motion correction; and the sensitivity analysis in high-quality datasets yielded no significant results. Findings suggest prominent alterations in posterior interhemispheric connections subserving cognitive and motor functions affected in ADHD, although these might be influenced by non-optimal acquisition parameters/preprocessing. Absence of findings in children may be related to the late development of callosal fibers, which may enhance case-control differences in adulthood. Clinicodemographic and methodological differences were major barriers to consistency and comparability among studies, and should be addressed in future investigations.
Topics: Adult; Humans; Child; White Matter; Attention Deficit Disorder with Hyperactivity; Diffusion Tensor Imaging; Brain; Corpus Callosum; Anisotropy
PubMed: 37479785
DOI: 10.1038/s41380-023-02173-1 -
Clinical Neurophysiology : Official... Oct 2023Cortico-cortical paired associative stimulation (ccPAS) is a form of dual-site transcranial magnetic stimulation (TMS) entailing a series of single-TMS pulses paired at...
OBJECTIVE
Cortico-cortical paired associative stimulation (ccPAS) is a form of dual-site transcranial magnetic stimulation (TMS) entailing a series of single-TMS pulses paired at specific interstimulus intervals (ISI) delivered to distant cortical areas. The goal of this article is to systematically review its efficacy in inducing plasticity in humans focusing on stimulation parameters and hypotheses of underlying neurophysiology.
METHODS
A systematic review of the literature from 2009-2023 was undertaken to identify all articles utilizing ccPAS to study brain plasticity and connectivity. Six electronic databases were searched and included.
RESULTS
32 studies were identified. The studies targeted connections within the same hemisphere or between hemispheres. 28 ccPAS studies were in healthy participants, 1 study in schizophrenia, and 1 in Alzheimer's disease (AD) patients. 2 additional studies used cortico-cortical repetitive paired associative stimulation (cc-rPAS) in generalized anxiety disorder (GAD) patients. Outcome measures include electromyography (EMG), behavioral measures, electroencephalography (EEG), and functional magnetic resonance imaging (fMRI). ccPAS seems to be able to modulate brain connectivity depending on the ISI.
CONCLUSIONS
ccPAS can be used to modulate corticospinal excitability, brain activity, and behavior. Although the stimulation parameters used across studies reviewed in this paper are varied, ccPAS is a promising approach for basic research and potential clinical applications.
SIGNIFICANCE
Recent advances in neuroscience have caused a shift of interest from the study of single areas to a more complex approach focusing on networks of areas that orchestrate brain activity. Consequently, the TMS community is also witnessing a change, with a growing interest in targeting multiple brain areas rather than a single locus, as evidenced by an increasing number of papers using ccPAS. In light of this new enthusiasm for brain connectivity, this review summarizes existing literature and stimulation parameters that have proven effective in changing electrophysiological, behavioral, or neuroimaging-derived measures.
Topics: Humans; Motor Cortex; Evoked Potentials, Motor; Transcranial Magnetic Stimulation; Brain; Neuronal Plasticity
PubMed: 37634335
DOI: 10.1016/j.clinph.2023.06.016 -
Developmental Cognitive Neuroscience Dec 2023Resting-state functional connectivity (rsFC) has the potential to shed light on how childhood abuse and neglect relates to negative psychiatric outcomes. However, a... (Review)
Review
Resting-state functional connectivity (rsFC) has the potential to shed light on how childhood abuse and neglect relates to negative psychiatric outcomes. However, a comprehensive review of the impact of childhood maltreatment on the brain's resting state functional organization has not yet been undertaken. We systematically searched rsFC studies in children and youth exposed to maltreatment. Nineteen studies (total n = 3079) met our inclusion criteria. Two consistent findings were observed. Childhood maltreatment was linked to reduced connectivity between the anterior insula and dorsal anterior cingulate cortex, and with widespread heightened amygdala connectivity with key structures in the salience, default mode, and prefrontal regulatory networks. Other brain regions showing altered connectivity included the ventral anterior cingulate cortex, dorsolateral prefrontal cortex, and hippocampus. These patterns of altered functional connectivity associated with maltreatment exposure were independent of symptoms, yet comparable to those seen in individuals with overt clinical disorder. Summative findings indicate that rsFC alterations associated with maltreatment experience are related to poor cognitive and social functioning and are prognostic of future symptoms. In conclusion, maltreatment is associated with altered rsFC in emotional reactivity, regulation, learning, and salience detection brain circuits. This indicates patterns of recalibration of putative mechanisms implicated in maladaptive developmental outcomes.
Topics: Adolescent; Humans; Child; Brain; Amygdala; Brain Mapping; Gyrus Cinguli; Child Abuse; Magnetic Resonance Imaging
PubMed: 37952287
DOI: 10.1016/j.dcn.2023.101322 -
Neurosurgical Review Sep 2023Recent literature demonstrates that a learning curve exists for endoscopic pituitary surgery. However, there is significant variability in the way these studies report... (Review)
Review
Recent literature demonstrates that a learning curve exists for endoscopic pituitary surgery. However, there is significant variability in the way these studies report their outcomes. This study aims to systematically review the literature regarding outcomes for endoscopic pituitary surgery and how this may be related to a surgical learning curve. An electronic search of the databases Medline, Scopus, Embase, Web of Science and Cochrane Library databases was performed and data extracted according 2020 Preferred Reporting Items of Systematic Reviews and Meta-Analyses (PRISMA) statement. Ten articles were included in the review as they examined the following: rates of gross total resection, average operative time, CSF leak rate, visual outcomes, endocrine outcomes and how these results were influenced by surgical experience. We have demonstrated that a learning curve exists for some outcome variables for endoscopic pituitary surgery. However, there is significant heterogeneity in the current body of literature which makes clear comparisons difficult.
Topics: Humans; Learning Curve; Pituitary Gland; Pituitary Diseases; Endoscopy; Databases, Factual
PubMed: 37698777
DOI: 10.1007/s10143-023-02136-8 -
Neuropsychology Review Dec 2023The central role of the corpus callosum in integrating perception and cognition across the cerebral hemispheres makes it highly desirable for clinical and basic research... (Meta-Analysis)
Meta-Analysis Review
The central role of the corpus callosum in integrating perception and cognition across the cerebral hemispheres makes it highly desirable for clinical and basic research to have a repertoire of experimental paradigms assessing callosal functioning. Here, the objective was to assess the validity of two such paradigms (Poffenberger, redundant-target paradigms) by conducting single-step meta-analyses on individual case data of callosotomy patients. Studies were identified by systematic literature search (source: Pubmed and WebOfKnowledge, date: 07.03.2022) and all studies were included that reported callosotomy case data for either paradigm. Twenty-two studies (38 unique cases) provided 116 observations of the crossed-uncrossed difference (CUD) for the Poffenberger paradigm, while ten studies (22 cases, 103 observations) provided bilateral redundancy gain (bRG) measures. Using linear-mixed models with "individual" and "experiment" as random-effects variable, the mean CUD was estimated at 60.6 ms (CI: 45.3; 75.9) for commissurotomy, 43.5 ms (26.7; 60.2) for complete callosotomy, and 8.8 ms (1.1; 16.6) for partial anterior-medial callosotomy patients. The estimates of commissurotomy/callosotomy patients differed significantly from patients with partial callosotomy and healthy controls. The mean bRG (minimum unilateral reference) was estimated at 42.8 ms (27.1;58.4) for patients with complete and 30.8 ms (16.8; 44.7) for patients with partial callosotomy, both differing significantly from controls. One limitation was that different formulas for bRG were used, making it necessary to split the sample and reducing test power of some analyses. Nevertheless, the present findings suggest that both paradigms assess interhemispheric callosal integration, confirming their construct validity, but likely test distinct callosal functions.
Topics: Humans; Cognition; Corpus Callosum; Functional Laterality
PubMed: 36484870
DOI: 10.1007/s11065-022-09569-w