scholarly journals Longitudinal Changes of Sensorimotor Resting-State Functional Connectivity Differentiate between Patients with Thalamic Infarction and Pontine Infarction

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Peipei Wang ◽  
Zhenxiang Zang ◽  
Miao Zhang ◽  
Yanxiang Cao ◽  
Zhilian Zhao ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Repeated Measures ◽  
Time Course ◽  
Stroke Onset ◽  
Repeated Measure ◽  
Precentral Gyrus ◽  
Resting State Functional Connectivity ◽  
Time Points ◽  
Thalamic Infarction ◽  
Pontine Infarction

Purpose. We investigated the disparate influence of lesion location on functional damage and reorganization of the sensorimotor brain network in patients with thalamic infarction and pontine infarction. Methods. Fourteen patients with unilateral infarction of the thalamus and 14 patients with unilateral infarction of the pons underwent longitudinal fMRI measurements and motor functional assessment five times during a 6-month period (<7 days, at 2 weeks, 1 month, 3 months, and 6 months after stroke onset). Twenty-five age- and sex-matched controls underwent MRI examination across five consecutive time points in 6 months. Functional images from patients with left hemisphere lesions were first flipped from the left to the right side. The voxel-wise connectivity analyses between the reference time course of each ROI (the contralateral dorsal lateral putamen (dl-putamen), pons, ventral anterior (VA), and ventral lateral (VL) nuclei of the thalamus) and the time course of each voxel in the sensorimotor area were performed for all five measurements. One-way ANOVA was used to identify between-group differences in functional connectivity (FC) at baseline stage (<7 days after stroke onset), with infarction volume included as a nuisance variable. The family-wise error (FWE) method was used to account for multiple comparison issues using SPM software. Post hoc repeated-measure ANOVA was applied to examine longitudinal FC reorganization. Results. At baseline stage, significant differences were detected between the contralateral VA and ipsilateral postcentral gyrus (cl_VA-ip_postcentral), contralateral VL and ipsilateral precentral gyrus (cl_VL-ip_precentral). Repeated measures ANOVA revealed that the FC change of cl_VA-ip_postcentral differ significantly among the three groups over time. The significant changes of FC between cl_VA and ip_postcentral at different time points in the thalamic infarction group showed that compared with 7 days after stroke onset, there was significantly increased FC of cl_VA-ip_postcentral at 1 month, 3 months, and 6 months after stroke onset. Conclusions. The different patterns of sensorimotor functional damage and reorganization in patients with pontine infarction and thalamic infarction may provide insights into the neural mechanisms underlying functional recovery after stroke.

scholarly journals Functional Connectivity and Networks Underlying Complex Tool-Use Movement in Assembly Workers: An fMRI Study

2021 ◽  
Vol 15 ◽  
Author(s):  
Seira Taniguchi ◽  
Yuichiro Higashi ◽  
Hirotaka Kataoka ◽  
Hiroshi Nakajima ◽  
Tetsuya Shimokawa
Keyword(s):  
Functional Connectivity ◽  
Tool Use ◽  
Repeated Measures ◽  
Inferior Frontal Gyrus ◽  
Real Life ◽  
Analysis Of Covariance ◽  
Repeated Measure ◽  
Angular Gyrus ◽  
Middle Temporal Gyrus ◽  
Resting State Functional Connectivity

The aim of this study was to identify the functional connectivity and networks utilized during tool-use in real assembly workers. These brain networks have not been elucidated because the use of tools in real-life settings is more complex than that in experimental environments. We evaluated task-related functional magnetic resonance imaging in 13 assembly workers (trained workers, TW) and 27 age-matched volunteers (untrained workers, UTW) during a tool-use pantomiming task, and resting-state functional connectivity was also analyzed. Two-way repeated-measures analysis of covariance was conducted with the group as a between-subject factor (TW &gt; UTW) and condition (task &gt; resting) as a repeated measure, controlling for assembly time and accuracy as covariates. We identified two patterns of functional connectivity in the whole brain within three networks that distinguished TW from UTW. TW had higher connectivity than UTW between the left middle temporal gyrus and right cerebellum Crus II (false discovery rate corrected p-value, p-FDR = 0.002) as well as between the left supplementary motor area and the pars triangularis of the right inferior frontal gyrus (p-FDR = 0.010). These network integrities may allow for TW to perform rapid tool-use. In contrast, UTW showed a stronger integrity compared to TW between the left paracentral lobule and right angular gyrus (p-FDR = 0.004), which may reflect a greater reliance on sensorimotor input to acquire complex tool-use ability than that of TW. Additionally, the fronto-parietal network was identified as a common network between groups. These findings support our hypothesis that assembly workers have stronger connectivity in tool-specific motor regions and the cerebellum, whereas UTW have greater involvement of sensorimotor networks during a tool-use task.

scholarly journals Functional connectome reorganization relates to post-stroke motor recovery and structural disconnection

2021 ◽  
Author(s):  
Emily Olafson ◽  
Keith Jamison ◽  
Elizabeth Sweeney ◽  
Hesheng Liu ◽  
Danhong Wang ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Time Course ◽  
Graph Matching ◽  
Brain Regions ◽  
Motor Recovery ◽  
First Episode ◽  
Resting State Functional Connectivity ◽  
Functional Reorganization ◽  
Time Points ◽  
Post Stroke

Motor recovery following ischemic stroke is contingent on the ability of surviving brain networks to compensate for damaged tissue. In rodent models, sensory and motor cortical representations have been shown to remap onto intact tissue around the lesion site, but remapping to more distal sites (e.g. in the contralesional hemisphere) has also been observed. Resting state functional connectivity (FC) analysis has been employed to study compensatory network adaptations in humans, but mechanisms and time course of motor recovery are not well understood. Here, we examine longitudinal FC in 23 first-episode ischemic pontine stroke patients (34-74 years old; 8 female, 15 male) and utilize a graph matching approach to identify patterns of regional functional connectivity reorganization during recovery. We quantified functional reorganization between several intervals ranging from 1 week to 6 months following stroke, and demonstrated that the areas that undergo functional reorganization most frequently are in cerebellar/subcortical networks. Brain regions with more structural connectome disruption due to the stroke also had more functional remapping over time. Finally, we show that the amount of functional reorganization between time points is correlated with the extent of motor recovery observed between those time points in the early to late subacute phases, and, furthermore, individuals with greater baseline motor impairment demonstrate more extensive early subacute functional reorganization (from one to two weeks post-stroke) and this reorganization correlates with better motor recovery at 6 months. Taken together, these results suggest that our graph matching approach can quantify recovery-relevant, whole-brain functional connectivity network reorganization after stroke.

scholarly journals Does Prior Surgery Affect Total Ankle Complication and Failure Rates?

2020 ◽  
Vol 5 (4) ◽  
pp. 2473011420S0034
Author(s):  
Luigi Manzi ◽  
Federico Giuseppe Usuelli ◽  
Alexander Caughman ◽  
Christopher E. Gross
Keyword(s):  
Functional Outcome ◽  
Repeated Measures ◽  
Functional Outcomes ◽  
Time Course ◽  
Temporal Evolution ◽  
Consecutive Series ◽  
Exact Test ◽  
Time Points ◽  
Significant Difference ◽  
Pain Outcomes

Category: Ankle Arthritis; Ankle Introduction/Purpose: Given that most ankle replacements are post-traumatic in origin, it is important to investigate if prior interventions can affect a patient’s functional outcome or the possibility of having a complication. Prior surgeries create scar, incisions, and possible affect bone health that could interfere with healing. The purpose of the study is to assess the pain and functional temporal outcomes of patients with and without prior surgeries in the ipsilateral ankle. We hypothesize that those with a previous ipsilateral ankle procedure will not have an increased complication rate or worse functional outcomes. Methods: We retrospectively identified a consecutive series of 100 primary TARs with a prior procedure who were followed for a minimum of 3 years. The follow-up time points considered were 0, 6, 12, and 36 months. Outcomes were measured using AOFAS, VAS, SF12, and range of motion scores. The mean patient age was 56.5 +- 13.4 years. Sixty-four patients had previous interventions which included osteosynthesis (49), arthroscopy (11), hardware removal (25), arthrodesis (3), prosthesis (1), open fracture (9), and other open surgery (12). Within-group comparisons were performed using one-way repeated-measures ANOVA (1-w rANOVA), analyzing temporal course of clinical data (comparisons between different time points) between the groups. To compare the time course of clinical measures between the two groups, 2-w rANOVAs were performed. Data and statistical analysis were conducted using Matlab (MathWorks, Natick, MA). Results: For each type of intervention, every outcome was compared to test whether presurgery interventions have an influence on the temporal evolution of the outcomes. The two groups did not show any difference on the temporal evolution of the outcomes. The type of intervention did have a weak effect on outcomes. Treatment of previous open fractures was the only pre- surgical intervention that showed a statistically significant difference in temporal evolution of functional and pain outcomes between intervention and non-intervention groups. No significant correlations were found between all outcomes and the time between the last intervention and prosthesis. Using Fisher’s-exact test, there was not a significant association between the those who had previous surgery and those who did not and the rate of complication and revision (p =0.10). Conclusion: A pre-operative discussion should center on potential complications and predicted functional outcomes. The presence, type, and timing of an intervention prior to an ankle replacement does not strongly affect the temporal outcomes of pain and functional outcome scores. Furthermore, the complication or revision rate is not affected by prior surgeries.

Dynamic modulation of intrinsic functional connectivity by transcranial direct current stimulation

2012 ◽  
Vol 108 (12) ◽  
pp. 3253-3263 ◽  
Author(s):  
Bernhard Sehm ◽  
Alexander Schäfer ◽  
Judy Kipping ◽  
Daniel Margulies ◽  
Virginia Conde ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Direct Current ◽  
Transcranial Direct Current Stimulation ◽  
Healthy Subjects ◽  
Time Course ◽  
Cortical Excitability ◽  
Eigenvector Centrality ◽  
Resting State Functional Connectivity ◽  
Brain Areas ◽  
Direct Current Stimulation

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique capable of modulating cortical excitability and thereby influencing behavior and learning. Recent evidence suggests that bilateral tDCS over both primary sensorimotor cortices (SM1) yields more prominent effects on motor performance in both healthy subjects and chronic stroke patients than unilateral tDCS over SM1. To better characterize the underlying neural mechanisms of this effect, we aimed to explore changes in resting-state functional connectivity during both stimulation types. In a randomized single-blind crossover design, 12 healthy subjects underwent functional magnetic resonance imaging at rest before, during, and after 20 min of unilateral, bilateral, and sham tDCS stimulation over SM1. Eigenvector centrality mapping (ECM) was used to investigate tDCS-induced changes in functional connectivity patterns across the whole brain. Uni- and bilateral tDCS over SM1 resulted in functional connectivity changes in widespread brain areas compared with sham stimulation both during and after stimulation. Whereas bilateral tDCS predominantly modulated changes in primary and secondary motor as well as prefrontal regions, unilateral tDCS affected prefrontal, parietal, and cerebellar areas. No direct effect was seen under the stimulating electrode in the unilateral condition. The time course of changes in functional connectivity in the respective brain areas was nonlinear and temporally dispersed. These findings provide evidence toward a network-based understanding regarding the underpinnings of specific tDCS interventions.

scholarly journals A Metabolomics Approach to the Identification of Urinary Biomarkers of Pea Intake

Nutrients ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1911 ◽  
Author(s):  
Pedapati S.C. Sri Harsha ◽  
Roshaida Abdul Wahab ◽  
Catalina Cuparencu ◽  
Lars Dragsted ◽  
Lorraine Brennan
Keyword(s):  
Mass Spectrometry ◽  
Repeated Measures ◽  
Time Course ◽  
Intervention Study ◽  
Random Order ◽  
Ultra Performance Liquid Chromatography ◽  
Nutritional Epidemiology ◽  
Dependent Manner ◽  
Time Points ◽  
Control Food

A significant body of evidence demonstrates that isoflavone metabolites are good markers of soy intake, while research is lacking on specific markers of other leguminous sources such as peas. In this context, the objective of our current study was to identify biomarkers of pea intake using an untargeted metabolomics approach. A randomized cross-over acute intervention study was conducted on eleven participants who consumed peas and couscous (control food) in random order. The urine samples were collected in fasting state and postprandially at regular intervals and were further analysed by ultra-performance liquid chromatography coupled to quadrupole time of flight mass spectrometry (UPLC-QTOF-MS). Multivariate statistical analysis resulted in robust Partial least squares Discriminant Analysis (PLS-DA) models obtained for comparison of fasting against the postprandial time points (0 h vs. 4 h, (R2X = 0.41, Q2 = 0.4); 0 h vs. 6 h, ((R2X = 0.517, Q2 = 0.495)). Variables with variable importance of projection (VIP) scores ≥1.5 obtained from the PLS-DA plot were considered discriminant between the two time points. Repeated measures analysis of variance (ANOVA) was performed to identify features with a significant time effect. Assessment of the time course profile revealed that ten features displayed a differential time course following peas consumption compared to the control food. The interesting features were tentatively identified using accurate mass data and confirmed by tandem mass spectrometry (MS using commercial spectral databases and authentic standards. 2-Isopropylmalic acid, asparaginyl valine and N-carbamoyl-2-amino-2-(4-hydroxyphenyl) acetic acid were identified as markers reflecting pea intake. The three markers also increased in a dose-dependent manner in a randomized intervention study and were further confirmed in an independent intervention study. Overall, key validation criteria were met for the successfully identified pea biomarkers. Future work will examine their use in nutritional epidemiology studies.

Prediction of headache severity (density and functional impact) after traumatic brain injury: A longitudinal multicenter study

Cephalalgia ◽  
2013 ◽  
Vol 33 (12) ◽  
pp. 998-1008 ◽  
Author(s):  
William C Walker ◽  
Jennifer H Marwitz ◽  
Amber R Wilk ◽  
Jessica M Ketchum ◽  
Jeanne M Hoffman ◽  
...  
Keyword(s):  
Risk Factors ◽  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Repeated Measures ◽  
Time Course ◽  
Time Points ◽  
Female Sex ◽  
Severe Tbi ◽  
Generalized Linear Mixed Effects ◽  
Prospective Longitudinal

Background: Headache (HA) following traumatic brain injury (TBI) is common, but predictors and time course are not well established, particularly after moderate to severe TBI. Methods: A prospective, longitudinal cohort study of HA severity post-TBI was conducted on 450 participants at seven participating rehabilitation centers. Generalized linear mixed-effects models (GLMMs) were used to model repeated measures (months 3, 6, and 12 post-TBI) of two outcomes: HA density (a composite of frequency, duration, and intensity) and HA disruptions to activities of daily living (ADL). Results: Although HA density and ADL disruptions were nominally highest during the first three months post-TBI, neither showed significant changes over time. At all time points, history of pre-injury migraine was by far the strongest predictor of both HA density and ADL disruptions (odds ratio (OR) = 8.0 and OR = 7.2, averaged across time points, respectively). Furthermore, pre-injury non-migraine HA (at three and six months post-TBI), penetrating-type TBI (at six months post-TBI), and female sex (at six and 12 months post-TBI) were each associated with an increase in the odds of a more severe HA density. Severity of TBI (post-traumatic amnesia (PTA) duration) was not associated with either outcome. Conclusion: Individuals with HA at three months after moderate-severe TBI do not improve over the ensuing nine months with respect to HA density or ADL disruptions. Those with pre-injury HA, particularly of migraine type, are at greatest risk for HA post-TBI. Other independent risk factors are penetrating-type TBI and, to a lesser degree and post-acutely only, female sex. Individuals with these risk factors should be monitored and considered for aggressive early intervention.

scholarly journals Dysbalanced Resting-State Functional Connectivity Within the Praxis Network Is Linked to Gesture Deficits in Schizophrenia

2020 ◽  
Vol 46 (4) ◽  
pp. 905-915 ◽  
Author(s):  
Florian Wüthrich ◽  
Petra V Viher ◽  
Katharina Stegmayer ◽  
Andrea Federspiel ◽  
Stephan Bohlhalter ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Resting State ◽  
Superior Temporal Gyrus ◽  
Brain Regions ◽  
Precentral Gyrus ◽  
Healthy Controls ◽  
Resting State Functional Connectivity ◽  
Neural Basis ◽  
Course Of Illness ◽  
Parietal Lobule

Abstract Patients with schizophrenia frequently present deficits in gesture production and interpretation, greatly affecting their communication skills. As these gesture deficits can be found early in the course of illness and as they can predict later outcomes, exploring their neural basis may lead to a better understanding of schizophrenia. While gesturing has been reported to rely on a left lateralized network of brain regions, termed praxis network, in healthy subjects and lesioned patients, studies in patients with schizophrenia are sparse. It is currently unclear whether within-network connectivity at rest is linked to gesture deficit. Here, we compared the functional connectivity between regions of the praxis network at rest between 46 patients and 44 healthy controls. All participants completed a validated test of hand gesture performance before resting-state functional magnetic resonance imaging (fMRI) was acquired. Patients performed gestures poorer than controls in all categories and domains. In patients, we also found significantly higher resting-state functional connectivity between left precentral gyrus and bilateral superior and inferior parietal lobule. Likewise, patients had higher connectivity from right precentral gyrus to left inferior and bilateral superior parietal lobule (SPL). In contrast, they exhibited lower connectivity between bilateral superior temporal gyrus (STG). Connectivity between right precentral gyrus and left SPL, as well as connectivity between bilateral STG, correlated with gesture performance in healthy controls. We failed to detect similar correlations in patients. We suggest that altered resting-state functional connectivity within the praxis network perturbs correct gesture planning in patients, reflecting the gesture deficit often seen in schizophrenia.

scholarly journals Timing Assessment of Response to Fluid Challenge in Patients with Septic Shock

2021 ◽  
Author(s):  
Hui-bin Huang ◽  
Biao Xu ◽  
Guang-Yun Liu ◽  
Bin Du
Keyword(s):  
Septic Shock ◽  
Repeated Measures ◽  
Time Course ◽  
Fluid Challenge ◽  
Time Points ◽  
Initial Resuscitation ◽  
Hemodynamic Variables ◽  
Assessment Time ◽  
Recorded Data ◽  
Time Courses

Abstract Objectives: Fluid challenge (FC) is most commonly used for fluid responsiveness (FR) evaluation, with a wide divergence in assessment time choices. Therefore, we aimed to explore the optimal assessment time for FC in patients with septic shock. Methods: A prospective cohort study was conducted. Septic shock patients who had experienced initial resuscitation and required an FC with 500 mL 4% gelatin or normal saline (NS) over 5-10 min were included. FR was defined by an increase in cardiac index (CI) >10%. FR and other predefined variables were recorded at baseline (Tb), immediately (T0), and at 10 (T1), 30 (T2), 45 (T3), 60 (T4), 90 (T5), and 120 (T6) min after FC. The incidence of FR and hemodynamic variables at predefined time points were recorded. Data were analyzed by repeated measures of analysis of variance. Results: 63 patients were enrolled, with 43 in the gelatin group and 20 in the NS group. Among the 45/63 (71%) responders, 31 were responded at T0 (ER), while 14 responded at T1 or later (LR). The proportion of NR, ER and LR was comparable between gelatin and NS groups. After FC, the time course of FR status was slightly different between gelatin and NS groups. In the gelatin group, FC induced most responders (69%, 31/45) and frequency of CI maximum (35%, 11/31) at T2 and sustained a positive FR status until T4; while in the NS group, FC induced most responders (55%, 11/20) and frequency of CI maximum (64%, 9/14) at T1, and sustained FR status until T1. Conclusions: Different time courses of FR were found between gelatin and NS group patients undergoing FC. Thus, when NS is used, FR should be performed within 10 min, while it is better to extend the assessment time to 30 min after FC when gelatin is used.

scholarly journals Robustness of sex-differences in functional connectivity over time in middle-aged marmosets

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Benjamin C. Nephew ◽  
Marcelo Febo ◽  
Ryan Cali ◽  
Kathryn P. Workman ◽  
Laurellee Payne ◽  
...  
Keyword(s):  
Sex Differences ◽  
Functional Connectivity ◽  
Cognitive Flexibility ◽  
Resting State ◽  
Cognitive Aging ◽  
Resting State Functional Connectivity ◽  
Common Marmosets ◽  
Time Points ◽  
Prefrontal Cortical ◽  
Age Related

Abstract Nonhuman primates (NHPs) are an essential research model for gaining a comprehensive understanding of the neural mechanisms of neurocognitive aging in our own species. In the present study, we used resting state functional connectivity (rsFC) to investigate the relationship between prefrontal cortical and striatal neural interactions, and cognitive flexibility, in unanaesthetized common marmosets (Callithrix jacchus) at two time points during late middle age (8 months apart, similar to a span of 5–6 years in humans). Based on our previous findings, we also determine the reproducibility of connectivity measures over the course of 8 months, particularly previously observed sex differences in rsFC. Male marmosets exhibited remarkably similar patterns of stronger functional connectivity relative to females and greater cognitive flexibility between the two imaging time points. Network analysis revealed that the consistent sex differences in connectivity and related cognitive associations were characterized by greater node strength and/or degree values in several prefrontal, premotor and temporal regions, as well as stronger intra PFC connectivity, in males compared to females. The current study supports the existence of robust sex differences in prefrontal and striatal resting state networks that may contribute to differences in cognitive function and offers insight on the neural systems that may be compromised in cognitive aging and age-related conditions such as mild cognitive impairment and Alzheimer’s disease.

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