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1.
J Affect Disord ; 263: 437-444, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31969275

RESUMO

BACKGROUND: Given that current unimodal strategies for treating late-life depression are insufficient, the awareness of the necessity and importance of multidomain intervention has increased. We assessed the efficacy of multidomain intervention in reducing symptoms of late-life depression. METHODS: This was a 12-week community-based randomized controlled trial in 78 older adults diagnosed with major depressive disorder. Participants were randomly assigned to the multidomain intervention or supportive therapy group. We provided four home visits and 12 telephone calls over 12 weeks. Four therapeutic approaches (physical activity, healthy diet, social activity, and brief cognitive restructuring) were incorporated into the multidomain intervention. The primary outcome was the change in depressive symptoms, as measured by the Montgomery-Asberg Depression Rating Scale (MADRS). Secondarily, we investigated changes in resting-state functional connectivity. RESULTS: The MADRS total score was reduced more in the multidomain intervention group than in the supportive therapy group during the 12 weeks (intervention × time interaction, P = =0.007). After correction for multiple comparisons, the multidomain intervention group exhibited a lower MADRS total score at week 12 (score difference 5.117; P = =0.029). At follow-up, the multidomain intervention group also exhibited less functional connectivity between the posterior cingulate cortex and left inferior parietal lobule within the default mode network (FDR < 0.1). LIMITATIONS: Caution is needed in the interpretation of the results, considering the small sample size and high percentage of female participants. CONCLUSIONS: A 12-week multidomain intervention resulted in a greater reduction of depressive symptoms among the elderly with major depressive disorder than their counterparts who received supportive therapy.

2.
J Korean Med Sci ; 35(3): e23, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31950778

RESUMO

BACKGROUND: Barley is a grain that is consumed in various forms in Asia. Studies on barley allergy are limited to a few case reports about hypersensitivity reactions to beer, but there is no barley allergy study in children. This study aimed to identify the phenotype and immunologic findings in Korean children with barley allergy. METHODS: Forty-two participants with a history of ingesting barley who underwent serum specific immunoglobulin E to barley (barley-sIgE) assay at the Department of Pediatrics in Ajou Medical Center were enrolled through a retrospective analysis of medical records from March 2008 to February 2018. The demographic characteristics, symptoms, and immunologic parameters of the patients were assessed. RESULTS: Twenty subjects presented with clinical barley allergy (B-allergic group), and 22 were atopic controls without allergic reactions after the ingestion of barley (B-tolerant group). The median ages of the B-allergic and B-tolerant groups were 1 and 3 years, respectively. In the B-allergic group, the cutaneous system (90.0%) was most frequently affected, followed by the respiratory system (40.0%). Anaphylaxis was observed in 35.0% of the B-allergic group. The median level of barley-sIgE was 13.90 kUA/L (range, 0.14-101.00 kUA/L) in the B-allergic group, and this value was significantly higher (P < 0.001) than that of the B-tolerant group (0.30 kUA/L; range, 0.01-24.40 kUA/L), with an optimal cutoff level of 1.24 kUA/L (sensitivity, 85.0%; specificity, 86.4%). A positive correlation was found between the serum levels of barley-sIgE and wheat-sIgE in the B-allergic group with clinical wheat allergy. CONCLUSION: Barley is an important allergen for children in Korea. This study showed the clinical characteristics of barley allergy and suggested optimal cut-off levels of barley-sIgE for clinical barley allergy. Clinically, cross-reactivity or co-sensitization is often observed between barley and wheat.

3.
Radiology ; : 191227, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31990269

RESUMO

Background The decision to perform endovascular treatment (EVT) for stroke related to vertebrobasilar occlusion (VBO) remains controversial. Purpose To identify preprocedural predictors of good outcomes and to develop a model to aid patient selection for VBO. Materials and Methods For this retrospective study using a Korean multicenter registry, a predictive model for good outcomes (modified Rankin scale score, 0-2) was generated based on a derivation sample of patients with VBO (January 2011-February 2016). Preprocedural parameters, including onset-to-puncture time, infarct volume, occlusion type as a surrogate marker of intracranial atherosclerotic stenosis-related occlusion or embolic occlusion (truncal-type occlusion vs branching site occlusion), and collateral status, were analyzed. Continuous variables were dichotomized based on receiver operating characteristic analysis. Multiple logistic regression analysis was performed to generate a predictive model. The model was internally validated with the bootstrap method and was externally validated with a single-center sample (April 2016-December 2018). Results A predictive model was generated from 71 patients (mean age, 67 years ± 11 [standard deviation]; 41 [58%] men) and was externally validated in 32 patients (mean age, 72 years ± 13; 19 [59%] men). The composite of initial DW imaging volume of less than 10 mL (odds ratio [OR], 19.3; 95% confidence interval [CI]: 3.0, 126.4; P = .002), onset-to-puncture time of less than 8 hours (OR, 8.7; 95% CI: 1.8, 42.0; P = .007), and branching-site occlusion (OR, 6.1; 95% CI: 1.5, 26.0; P = .01) could be used to predict good outcomes, with a median area under the receiver operating characteristic curve of 0.86 (interquartile range [IQR], 0.77-0.95; bootstrap optimism-corrected C statistic, 0.837) in the derivation sample and 0.78 (IQR, 0.62-0.95) in the validation sample. Results failed to show an association between collateral status and outcome (P = .67). Conclusion When selecting patients with vertebrobasilar occlusion for endovascular treatment, the combination of onset-to-puncture time of less than 8 hours, initial infarct volume of less than 10 mL, and presence of branching-site occlusions is indicative of a good outcome. © RSNA, 2020 Online supplemental material is available for this article.

4.
Ann Thorac Surg ; 109(2): 496-503, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31336071

RESUMO

BACKGROUND: Long-term outcomes of mitral valve replacement (MVR) recipients with pulmonary hypertension (PH) remain unclear. We determined the effect of concomitant PH on the clinical outcomes and late-onset progression of tricuspid regurgitation (TR) after MVR for rheumatic mitral stenosis. METHODS: We retrospectively reviewed 394 patients who underwent MVR between January 2000 and December 2013. PH was defined as systolic pulmonary arterial pressure (sPAP) >50 mm Hg. Changes in echocardiographic parameters (preoperative to postoperative), TR progression (grade ≥ II), and long-term survival were evaluated according to the presence of PH at MVR (non-PH, n = 322; PH, n = 72). RESULTS: The 10-year overall survival rate was significantly lower in the PH group (79.7% vs 90.7%, P = .04), whereas the rate of freedom from TR progression was similar between groups (76.9% vs 80.5%, P = .373). High preoperative sPAP and right ventricular systolic pressure (RVSP) did not affect TR progression. However, substantial postoperative reductions in sPAP and RVSP protected against TR progression (hazard ratio [95% confidence interval], 0.966 [0.942-0.991], P = .008, and 0.973 [0.960-0.986], P < .001, respectively). The 10-year rate of freedom from TR progression was significantly higher in patients with substantial sPAP and RVSP reductions (sPAP, 84.2% vs 70.6%, P = .003; RVSP, 84.9% vs 71.0%, P < .001). CONCLUSIONS: Although concomitant PH at MVR is associated with poor long-term survival, adequate sPAP and RVSP reduction can prevent TR progression even in patients with severe PH preoperatively. Therefore, we suggest careful monitoring of PAP and RVSP after MVR and should make an effort to reduce postoperative PAP.

5.
Front Psychiatry ; 10: 856, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824354

RESUMO

Background: Depression and anxiety are the most common comorbid psychiatric disorders in the elderly. Psychiatrists have been reporting worsened depression symptoms and prognosis by comorbid anxiety symptoms. However, it is still unclear how anxiety affects the course of depression in the elderly. The aims of this study are (1) to identify the symptom network in late-life depression (LLD), and (2) to examine the role of anxiety in LLD with a network perspective. Methods: The study analyzed 776 community-based participants who were clinically diagnosed with depression and enrolled in Suwon Geriatric Mental Health Center. Network analysis was used to investigate the relationships between the symptoms of the Montgomery-Åsberg Depression Rating Scale (MADRS). The depression sample was divided into groups of low and high anxiety according to the Beck Anxiety Index. Propensity score matching (PSM) was used to minimize the effects of depression severity on the network. Network comparison test (NCT) were carried out to compare the global connectivity, global strength, and specific edge strength between the two subgroups. Results: Reported sadness, pessimistic thinking, and suicidal ideation are the core symptoms of LLD in terms of node strength. The MADRS sum score [mean (SD) 28.10 (9.19) vs 20.08 (7.11); P < .01] was much higher in the high anxiety group. The NCT before PSM showed the high anxiety group had significantly higher global strength (P < .01). However, the NCT after PSM did not reveal any statistical significance both in global structure (P = .46) and global strength (P = .26). A comparison between centrality indices showed a higher node strength of vegetative symptoms in the high anxiety group and this also remained after PSM. Conclusion: Based on the statistical analysis, anxiety worsens the severity of depression in the elderly. However, NCT after PSM revealed comorbid anxiety does not change the global structure and strength of the depression symptom network. Therefore, anxiety may affect LLD in a way of worsening the severity, rather than changing psychopathology. Additionally, the study revealed the centrality of vegetative symptoms was low in LLD but increased substantially in patients with comorbid anxiety.

6.
Gut Liver ; 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31818048

RESUMO

Background/Aims: Adequate bowel preparation is important for successful colonoscopy. We aimed to evaluate the clinical feasibility and effectiveness of abdominal vibration stimulation in bowel preparation before therapeutic colonoscopy. Methods: A single center, prospective, randomized, investigator-blinded study was performed between January 2016 and December 2016. Patients for therapeutic colonoscopy were prospectively enrolled and assigned to either the vibrator group or walking group. Patients who refused to participate in this study as part of the experimental group consented to register in the control group instead. During the preparation period, patients assigned to the walking group walked ≥3,000 steps, whereas those assigned to the vibrator group received abdominal vibrator stimulation and restricted walking. All patients received the same colon cleansing regimen: 4-L split-dose polyethylene glycol (PEG) solution. Results: Three hundred patients who received PEG solution for therapeutic colonoscopy were finally enrolled in this study (n=100 per group). Bowel cleansing with abdominal vibration stimulation showed almost similar results to that with walking exercise (Boston Bowel Preparation Scale score for the entire colon: vibrator vs walking vs control, 7.38±1.55 vs 7.39±1.55 vs 6.17±1.15, p<0.001). There were no significant differences between the vibrator group and walking group regarding instances of diarrhea after taking PEG, time to first diarrhea after taking PEG, total procedure time, and patient satisfaction. Conclusions: This study indicates that, compared with conventional walking exercise, abdominal vibration stimulation achieved similar rates of bowel cleansing adequacy and colonoscopy success without compromising safety or patient satisfaction.

7.
Medicine (Baltimore) ; 98(50): e18233, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31852086

RESUMO

Percutaneous epidural neuroplasty (PEN) is an effective interventional treatment for radicular pain. However, in some cases, contrast runoff to the spinal nerve root does not occur. We investigated whether contrast runoff to the spinal nerve root affects the success rate of PEN and whether additional transforaminal epidural blocks for intentional contrast runoff affect the success rate of PEN in cases in which contrast runoff is absent.This study was registered at ClinicalTrials.gov (Identifier: NCT03867630) in March 2019. We reviewed the medical records of 112 patients who underwent PEN with a wire-type catheter from May 2016 to August 2018. Patients were divided in 3 groups (Runoff group, Non-runoff group, Transforaminal group).Patients with low back pain and leg radicular pain who did not respond to lumbar epidural steroid injectionsPEN was performed in 112 patients with a wire-type catheter in target segment. We compared the success rate of PEN betweenThe success rate was significantly different between the Runoff group and the Non-runoff group (P < .0007) and between the Non-runoff group and the Transforaminal group (P = .0047), but not between the Runoff group and the Transforaminal group (P = .57).Contrast runoff influenced the success rate of PEN. In cases without contrast runoff, additional transforaminal epidural blocks for intentional contrast runoff increased the success rate of PEN with a wire-type catheter.


Assuntos
Anestesia Epidural/instrumentação , Cateteres , Dor Lombar/terapia , Procedimentos Neurocirúrgicos/métodos , Manejo da Dor/métodos , Raízes Nervosas Espinhais/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fluoroscopia , Seguimentos , Humanos , Injeções Epidurais/métodos , Dor Lombar/diagnóstico , Região Lombossacral , Masculino , Pessoa de Meia-Idade , Medição da Dor , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
8.
Front Psychiatry ; 10: 615, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31555158

RESUMO

Background: It has been suggested that maintaining the efficient organization of the brain's functional connectivity (FC) supports neuroflexibility under neurogenerative stress. This study examined psychological resilience-related FC in 112 older adults with mild cognitive impairment (MCI). Methods: Using a resting-state functional magnetic resonance imaging (fMRI) approach, we investigated reorganization of the orbitofrontal gyrus (OFG)/amygdala (AMG)/hippocampus (HP)/parahippocampal gyrus (PHG) FC according to the different levels of resilience scale. Results: Compared with the low resilient group, the high resilient group had greater connectivity strengths between the left inferior OFG and right superior OFG (P < 0.05, Bonferroni corrected), between the right inferior OFG and left PHG (P < 0.05, Bonferroni corrected), and between the right middle OFG and left PHG (false discovery rate < 0.05). Conclusion: Psychological resilience may be associated with enhancement of the orbitofrontal network in the elderly with MCI.

9.
J Clin Med ; 8(7)2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295896

RESUMO

Osteoarthritis (OA) is considered to be one of the most disabling diseases. The intra-articular opioid injection has been widely studied for its simplicity, safety, and efficacy in OA. In this study, however, we suggest a novel method of buprenorphine transdermal patch (BTDP) to painful knee joints of OA patients, instead of intra-articular opioid injection, and subsequently compared the knee application with conventional chest application. We retrospectively enrolled 213 patients with knee OA who did not respond to conventional therapy. The Numeric Rating Scale (NRS), adverse effects, and compliance were recorded before and after the application of the BTDP. All parameters were compared between the knee applied group and the chest applied group. After the BTDP application, the NRS score in the knee applied group was lower than that of the chest applied group (p = 0.007). NRS scores after buprenorphine patch decreased to 2.21 ± 0.77, and 2.55 ± 0.71 in the chest applied group and the knee applied group, respectively. The adverse effects were 19.32% in the knee applied group, and 64.00% in the chest applied group. The compliances were 82.95% and 37.60% in the knee applied group and chest applied group, respectively. This novel application of BTDP directly to the painful knee joint of knee OA patients led to a decrease in the NRS score, adverse effects, and an increase in compliance compared with the chest application method.

10.
Medicine (Baltimore) ; 98(15): e15084, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30985662

RESUMO

Sphenopalatine ganglion block (SPGB) is a technique developed in the 1990s for the management of head and neck pain patients. Recently, transnasal sphenopalatine ganglion block (TN-SPGB) has been widely used for these patients; however, no objective methods exist for validating the success of TN-SPGB. In this study, we measured the changes in facial temperature before and 30 minutes after TN-SPGB by using digital infrared thermal imaging (DITI) to validate its success.The medical records of patients, who underwent TN-SPGB and facial DITI between January 2016 and December 2017, were reviewed. TN-SPGB and facial DITI were performed 36 times in 32 patients. The changes in facial temperatures measured at the forehead (V1), maxillary area (V2), and mandibular area (V3) by using DITI before and 30 minutes after TN-SPGB were recorded and compared. The temperatures on the ipsilateral and contralateral sides of these areas were also compared. The comparison between pain relief group and pain maintenance group was analyzed.After TN-SPGB, the temperature decreased significantly on both sides of V1 (P = .0208, 0.0181). No significant differences were observed between the ipsilateral and contralateral sides (P > .05). There was no correlation between changes in temperature and changes in pain score in the pain regions after the procedure (P > .05).The temperature decreased significantly in V1 area at 30 minutes after TN-SPGB compared with the temperature before TN-SPGB. Based on these results, we propose using DITI to measure temperature changes as an objective method for verifying the success of TN-SPGB.


Assuntos
Temperatura Corporal , Bloqueio do Gânglio Esfenopalatino , Face , Feminino , Humanos , Raios Infravermelhos , Masculino , Pessoa de Meia-Idade , Dor/diagnóstico , Dor/fisiopatologia , Manejo da Dor , Estudos Retrospectivos , Termografia , Resultado do Tratamento
11.
Sci Rep ; 9(1): 855, 2019 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-30696877

RESUMO

The cerebellum is an important region responsible for adolescent cognitive function and sleep, and their correlation is expected to show different patterns depending on age and gender. We examined the regional cerebellar gray matter volume (GMV), executive function (EF) and insomnia symptoms to identify their correlation and gender differences in adolescents. Data for a total of 55 subjects' (M = 31, F = 24, 14.80 ± 1.39 years old) were analyzed. The correlations between cerebellar regional GMV and Wisconsin card sorting test (WCST) subcategories showed that EF was better with larger GMV both in males and females. Far more overall correlations with cerebellar regions were observed in boys, with corresponding correlation strength being higher, and differences in localization were also observed in contrast to girls. Larger cerebellar GMV corresponded to better EF in adolescents. Insomnia did not influence the correlations between cerebellar regional GMV and EF, but more severe insomnia in boys correlated to smaller GMV in the right flocculonodular lobe. These results might implicate that the adolescent cerebellum is involved differently in EF dependent on gender.

12.
Neuroimage ; 180(Pt B): 594-608, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-29158202

RESUMO

Context-sensitive and activity-dependent fluctuations in connectivity underlie functional integration in the brain and have been studied widely in terms of synaptic plasticity, learning and condition-specific (e.g., attentional) modulations of synaptic efficacy. This dynamic aspect of brain connectivity has recently attracted a lot of attention in the resting state fMRI community. To explain dynamic functional connectivity in terms of directed effective connectivity among brain regions, we introduce a novel method to identify dynamic effective connectivity using spectral dynamic causal modelling (spDCM). We used parametric empirical Bayes (PEB) to model fluctuations in directed coupling over consecutive windows of resting state fMRI time series. Hierarchical PEB can model random effects on connectivity parameters at the second (between-window) level given connectivity estimates from the first (within-window) level. In this work, we used a discrete cosine transform basis set or eigenvariates (i.e., expression of principal components) to model fluctuations in effective connectivity over windows. We evaluated the ensuing dynamic effective connectivity in terms of the consistency of baseline connectivity within default mode network (DMN), using the resting state fMRI from Human Connectome Project (HCP). To model group-level baseline and dynamic effective connectivity for DMN, we extended the PEB approach by conducting a multilevel PEB analysis of between-session and between-subject group effects. Model comparison clearly spoke to dynamic fluctuations in effective connectivity - and the dynamic functional connectivity these changes explain. Furthermore, baseline effective connectivity was consistent across independent sessions - and notably more consistent than estimates based upon conventional models. This work illustrates the advantage of hierarchical modelling with spDCM, in characterizing the dynamics of effective connectivity.


Assuntos
Encéfalo/fisiologia , Conectoma/métodos , Imagem por Ressonância Magnética/métodos , Modelos Neurológicos , Rede Nervosa/fisiologia , Descanso/fisiologia , Adulto , Teorema de Bayes , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Vias Neurais/fisiologia
13.
Neuroimage ; 169: 485-495, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29284140

RESUMO

Although the relationship between resting-state functional connectivity and task-related activity has been addressed, the relationship between task and resting-state directed or effective connectivity - and its behavioral concomitants - remains elusive. We evaluated effective connectivity under an N-back working memory task in 24 participants using stochastic dynamic causal modelling (DCM) of 7 T fMRI data. We repeated the analysis using resting-state data, from the same subjects, to model connectivity among the same brain regions engaged by the N-back task. This allowed us to: (i) examine the relationship between intrinsic (task-independent) effective connectivity during resting (Arest) and task states (Atask), (ii) cluster phenotypes of task-related changes in effective connectivity (Btask) across participants, (iii) identify edges (Btask) showing high inter-individual effective connectivity differences and (iv) associate reaction times with the similarity between Btask and Arest in these edges. We found a strong correlation between Arest and Atask over subjects but a marked difference between Btask and Arest. We further observed a strong clustering of individuals in terms of Btask, which was not apparent in Arest. The task-related effective connectivity Btask varied highly in the edges from the parietal to the frontal lobes across individuals, so the three groups were clustered mainly by the effective connectivity within these networks. The similarity between Btask and Arest at the edges from the parietal to the frontal lobes was positively correlated with 2-back reaction times. This result implies that a greater change in context-sensitive coupling - from resting-state connectivity - is associated with faster reaction times. In summary, task-dependent connectivity endows resting-state connectivity with a context sensitivity, which predicts the speed of information processing during the N-back task.


Assuntos
Córtex Cerebral/fisiologia , Conectoma/métodos , Função Executiva/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Memória de Curto Prazo/fisiologia , Modelos Teóricos , Rede Nervosa/fisiologia , Adulto , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Adulto Jovem
14.
Sci Rep ; 7(1): 13213, 2017 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-29038507

RESUMO

The neurobiological basis of social dysfunction and the high male prevalence in autism spectrum disorder (ASD) remain poorly understood. Although network alterations presumably underlie the development of autistic-like behaviors, a clear pattern of connectivity differences specific to ASD has not yet emerged. Because the heterogeneous nature of ASD hinders investigations in human subjects, we explored brain connectivity in an etiologically homogenous rat model of ASD induced by exposure to valproic acid (VPA) in utero. We performed partial correlation analysis of cross-sectional resting-state 18F-fluorodeoxyglucose positron emission tomography scans from VPA-exposed and control rats to estimate metabolic connectivity and conducted canonical correlation analysis of metabolic activity and behavior scores. VPA-treated rats exhibited impairments in social behaviors, and this difference was more pronounced in male than female rats. Similarly, current analyses revealed sex-specific changes in network connectivity and identified distinct alterations in the distributed metabolic activity patterns associated with autistic-like social deficits. Specifically, diminished activity in the salience network and enhanced activity in a cortico-cerebellar circuit correlated with the severity of social behavioral deficits. Such metabolic connectivity features may represent neurobiological substrates of autistic-like behavior, particularly in males, and may serve as a pathognomonic sign in the VPA rat model of ASD.


Assuntos
Transtorno do Espectro Autista/metabolismo , Encéfalo/metabolismo , Comportamento Social , Animais , Transtorno do Espectro Autista/fisiopatologia , Modelos Animais de Doenças , Feminino , Masculino , Tomografia por Emissão de Pósitrons , Ratos , Caracteres Sexuais
15.
Front Hum Neurosci ; 11: 408, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28848416

RESUMO

The idea that structural white matter connectivity constrains functional connectivity (interactions among brain regions) has widely been explored in studies of brain networks; studies have mostly focused on the "average" strength of functional connectivity. The question of how structural connectivity constrains the "variability" of functional connectivity remains unresolved. In this study, we investigated the variability of resting state functional connectivity that was acquired every 3 h within a single day from 12 participants (eight time sessions within a 24-h period, 165 scans per session). Three different types of functional connectivity (functional connectivity based on Pearson correlation, direct functional connectivity based on partial correlation, and the pseudo functional connectivity produced by their difference) were estimated from resting state functional magnetic resonance imaging data along with structural connectivity defined using fiber tractography of diffusion tensor imaging. Those types of functional connectivity were evaluated with regard to properties of structural connectivity (fiber streamline counts and lengths) and types of structural connectivity such as intra-/inter-hemispheric edges and topological edge types in the rich club organization. We observed that the structural connectivity constrained the variability of direct functional connectivity more than pseudo-functional connectivity and that the constraints depended strongly on structural connectivity types. The structural constraints were greater for intra-hemispheric and heterologous inter-hemispheric edges than homologous inter-hemispheric edges, and feeder and local edges than rich club edges in the rich club architecture. While each edge was highly variable, the multivariate patterns of edge involvement, especially the direct functional connectivity patterns among the rich club brain regions, showed low variability over time. This study suggests that structural connectivity not only constrains the strength of functional connectivity, but also the within-a-day variability of functional connectivity and connectivity patterns, particularly the direct functional connectivity among brain regions.

16.
Sci Rep ; 7: 41414, 2017 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-28112247

RESUMO

Individuality, the uniqueness that distinguishes one person from another, may manifest as diverse rearrangements of functional connectivity during heterogeneous cognitive demands; yet, the neurobiological substrates of individuality, reflected in inter-individual variations of large-scale functional connectivity, have not been fully evidenced. Accordingly, we explored inter-individual variations of functional connectivity dynamics, subnetwork patterns and modular architecture while subjects watched identical video clips designed to induce different arousal levels. How inter-individual variations are manifested in the functional brain networks was examined with respect to four contrasting divisions: edges within the anterior versus posterior part of the brain, edges with versus without corresponding anatomically-defined structural pathways, inter- versus intra-module connections, and rich club edge types. Inter-subject variation in dynamic functional connectivity occurred to a greater degree within edges localized to anterior rather than posterior brain regions, without adhering to structural connectivity, between modules as opposed to within modules, and in weak-tie local edges rather than strong-tie rich-club edges. Arousal level significantly modulates inter-subject variability in functional connectivity, edge patterns, and modularity, and particularly enhances the synchrony of rich-club edges. These results imply that individuality resides in the dynamic reconfiguration of large-scale brain networks in response to a stream of cognitive demands.


Assuntos
Encéfalo/fisiologia , Filmes Cinematográficos , Rede Nervosa/fisiologia , Adulto , Feminino , Humanos , Masculino , Estatística como Assunto
17.
J Comput Assist Tomogr ; 41(2): 181-189, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27801694

RESUMO

OBJECTIVE: Obstructive sleep apnea (OSA) is accompanied by brain changes in areas that regulate autonomic, cognitive, and mood functions, which were initially examined by Gaussian-based diffusion tensor imaging measures, but can be better assessed with non-Gaussian measures. We aimed to evaluate axonal and myelin changes in OSA using axial (AK) and radial kurtosis (RK) measures. MATERIALS AND METHODS: We acquired diffusion kurtosis imaging data from 22 OSA and 26 controls; AK and RK maps were calculated, normalized, smoothed, and compared between groups using analysis of covariance. RESULTS: Increased AK, indicating axonal changes, emerged in the insula, hippocampus, amygdala, dorsolateral pons, and cerebellar peduncles and showed more axonal injury over previously identified damage. Higher RK, showing myelin changes, appeared in the hippocampus, amygdala, temporal and frontal lobes, insula, midline pons, and cerebellar peduncles and showed more widespread myelin damage over previously identified injury. CONCLUSIONS: Axial kurtosis and RK measures showed widespread changes over Gaussian-based techniques, suggesting a more sensitive nature of kurtoses to injury.


Assuntos
Axônios , Imagem de Tensor de Difusão/métodos , Bainha de Mielina , Apneia Obstrutiva do Sono/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Estudos Transversais , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Apneia Obstrutiva do Sono/fisiopatologia
19.
J Neurosci Res ; 94(10): 915-923, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27315771

RESUMO

Obstructive sleep apnea (OSA) is characterized by recurrent upper airway blockage, with continued diaphragmatic efforts to breathe during sleep. Brain structural changes in OSA appear in various regions, including white matter sites that mediate autonomic, mood, cognitive, and respiratory control. However, the relationships between brain white matter changes and disease severity in OSA are unclear. This study examines associations between an index of tissue integrity, magnetization transfer (MT) ratio values (which show MT between free and proton pools associated with tissue membranes and macromolecules), and disease severity (apnea-hypopnea index [AHI]) in OSA subjects. We collected whole-brain MT imaging data from 19 newly diagnosed, treatment-naïve OSA subjects (50.4 ± 8.6 years of age, 13 males, AHI 39.7 ± 24.3 events/hr], using a 3.0-Tesla MRI scanner. With these data, whole-brain MT ratio maps were calculated, normalized to common space, smoothed, and correlated with AHI scores by using partial correlation analyses (covariates, age and gender; P < 0.005). Multiple brain sites in OSA subjects, including superior and inferior frontal regions, ventral medial prefrontal cortex and nearby white matter, midfrontal white matter, insula, cingulate and cingulum bundle, internal and external capsules, caudate nuclei and putamen, basal forebrain, hypothalamus, corpus callosum, and temporal regions, showed principally lateralized negative correlations (P < 0.005). These regions showed significant correlations even with correction for multiple comparisons (cluster-level, family-wise error, P < 0.05), except for a few superior frontal areas. Predominantly negative correlations emerged between local MT values and OSA disease severity, indicating potential usefulness of MT imaging for examining the OSA condition. These findings indicate that OSA severity plays a significant role in white matter injury. © 2016 Wiley Periodicals, Inc.


Assuntos
Mapeamento Encefálico , Encéfalo/diagnóstico por imagem , Apneia Obstrutiva do Sono/patologia , Substância Branca/diagnóstico por imagem , Adulto , Sintomas Afetivos/diagnóstico por imagem , Sintomas Afetivos/etiologia , Estudos Transversais , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Polissonografia , Escalas de Graduação Psiquiátrica , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/diagnóstico por imagem
20.
PLoS One ; 11(5): e0155894, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27203600

RESUMO

Heart failure (HF) patients show brain injury in autonomic, affective, and cognitive sites, which can change resting-state functional connectivity (FC), potentially altering overall functional brain network organization. However, the status of such connectivity or functional organization is unknown in HF. Determination of that status was the aim here, and we examined region-to-region FC and brain network topological properties across the whole-brain in 27 HF patients compared to 53 controls with resting-state functional MRI procedures. Decreased FC in HF appeared between the caudate and cerebellar regions, olfactory and cerebellar sites, vermis and medial frontal regions, and precentral gyri and cerebellar areas. However, increased FC emerged between the middle frontal gyrus and sensorimotor areas, superior parietal gyrus and orbito/medial frontal regions, inferior temporal gyrus and lingual gyrus/cerebellar lobe/pallidum, fusiform gyrus and superior orbitofrontal gyrus and cerebellar sites, and within vermis and cerebellar areas; these connections were largely in the right hemisphere (p<0.005; 10,000 permutations). The topology of functional integration and specialized characteristics in HF are significantly changed in regions showing altered FC, an outcome which would interfere with brain network organization (p<0.05; 10,000 permutations). Brain dysfunction in HF extends to resting conditions, and autonomic, cognitive, and affective deficits may stem from altered FC and brain network organization that may contribute to higher morbidity and mortality in the condition. Our findings likely result from the prominent axonal and nuclear structural changes reported earlier in HF; protecting neural tissue may improve FC integrity, and thus, increase quality of life and reduce morbidity and mortality.


Assuntos
Encéfalo/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Adulto , Idoso , Mapeamento Encefálico , Cerebelo/fisiopatologia , Feminino , Lobo Frontal/fisiopatologia , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Lobo Parietal/fisiopatologia , Córtex Sensório-Motor/fisiopatologia , Lobo Temporal/fisiopatologia
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