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1.
Neuroinformatics ; 22(1): 45-62, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37924429

RESUMO

BOLD-based fMRI is the most widely used method for studying brain function. The BOLD signal while valuable, is beset with unique vulnerabilities. The most notable of these is the modest signal to noise ratio, and the relatively low temporal and spatial resolution. However, the high dimensional complexity of the BOLD signal also presents unique opportunities for functional discovery. Topological Data Analyses (TDA), a branch of mathematics optimized to search for specific classes of structure within high dimensional data may provide particularly valuable applications. In this investigation, we acquired fMRI data in the anterior cingulate cortex (ACC) using a basic motor control paradigm. Then, for each participant and each of three task conditions, fMRI signals in the ACC were summarized using two methods: a) TDA based methods of persistent homology and persistence landscapes and b) non-TDA based methods using a standard vectorization scheme. Finally, using machine learning (with support vector classifiers), classification accuracy of TDA and non-TDA vectorized data was tested across participants. In each participant, TDA-based classification out-performed the non-TDA based counterpart, suggesting that our TDA analytic pipeline better characterized task- and condition-induced structure in fMRI data in the ACC. Our results emphasize the value of TDA in characterizing task- and condition-induced structure in regional fMRI signals. In addition to providing our analytical tools for other users to emulate, we also discuss the unique role that TDA-based methods can play in the study of individual differences in the structure of functional brain signals in the healthy and the clinical brain.


Assuntos
Mapeamento Encefálico , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Giro do Cíngulo , Análise de Dados
2.
Front Psychiatry ; 13: 869106, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36032258

RESUMO

Abnormal function of the thalamo-cortical relay is considered a hallmark of obsessive-compulsive disorder (OCD) and aberrant network interactions may underpin many of the clinical and cognitive symptoms that characterize the disorder. Several statistical approaches have been applied to in vivo fMRI data to support the general loss of thalamo-cortical connectivity in OCD. However, (a) few studies have assessed the contextual constraints under which abnormal network interactions arise or (b) have used methods of effective connectivity to understand abnormal network interactions. Effective connectivity is a particularly valuable method as it describes the putative causal influences that brain regions exert over each other, as opposed to the largely statistical consistencies captured in functional connectivity techniques. Here, using dynamic causal modeling (DCM), we evaluated how attention demand induced inter-group differences (HC ≠ OCD) in effective connectivity within a motivated thalamo-cortical network. Of interest was whether these effects were observed on the ascending thalamo-cortical relay, essential for the sensory innervation of the cortex. fMRI time series data from sixty-two participants (OCD, 30; HC, 32) collected using an established sustained attention task were submitted to a space of 162 competing models. Across the space, models distinguished between competing hypotheses of thalamo-cortical interactions. Bayesian model selection (BMS) identified marginally differing likely generative model architectures in OCD and HC groups. Bayesian model averaging (BMA), was used to weight connectivity parameter estimates across all models, with each parameter weighted by each model's posterior probability, thus providing more stable estimates of effective connectivity. Inferential statistical analyses of estimated parameters revealed two principal results: (1) Significantly reduced intrinsic connectivity of the V1 → SPC pathway in OCD, suggested connective weakness in the early constituents of the dorsal visual pathway; (2) More pertinent with the discovery possibilities afforded by DCM, sustained attention in OCD patients induced significantly reduced contextual modulation of the ascending relay from the thalamus to the prefrontal cortex. These results form an important complement to our understanding of the contextual bases of thalamo-cortical network deficits in OCD, emphasizing vulnerability of the ascending relay.

3.
J Affect Disord ; 312: 208-216, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35697331

RESUMO

BACKGROUND: Obsessive-compulsive disorder (OCD) is an often disabling and chronic condition that is normally assessed using diagnostic interviews or lengthy self-report questionnaires. This makes routine screening in general health settings impractical, and as a result OCD is often under-(or mis-)recognized. The present study reports on the development of an ultra-brief version of the Obsessive-Compulsive Inventory-Child Version (OCI-CV) which may be administered routinely as a screener for pediatric OCD. METHOD: A total of 489 youth diagnosed with OCD, 259 non-clinical controls, and 299 youth with other disorders completed the OCI-CV and other indices of psychopathology. Using item analyses, we extracted five items and examined the measure's factor structure, sensitivity and specificity, and convergent and discriminant validity. RESULTS: We extracted five items that assess different dimensions of OCD (washing, checking, ordering, obsessing, neutralizing/counting), termed the OCI-CV-5. Results revealed that the measure possesses good to excellent psychometric properties, and a cutoff off (≥2) yielded optimal sensitivity and specificity. LIMITATIONS: Participants were predominantly White. In addition, more research is needed to examine the OCI-CV-5's test-retest reliability and sensitivity to treatment. CONCLUSIONS: The OCI-CV-5 shows promise as an ultra-brief self-report screener for identifying OCD in youth when in-depth assessment is unfeasible.


Assuntos
Transtorno Obsessivo-Compulsivo , Adolescente , Criança , Humanos , Transtorno Obsessivo-Compulsivo/diagnóstico , Escalas de Graduação Psiquiátrica , Psicometria/métodos , Reprodutibilidade dos Testes , Inquéritos e Questionários
4.
J Anxiety Disord ; 86: 102532, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35091252

RESUMO

BACKGROUND: The Obsessive-Compulsive Inventory-Children's Version (OCI-CV) was developed to assess obsessive-compulsive symptoms in youth. Recent changes in the Diagnostic and Statistical Manual (DSM-5) exclude hoarding from inclusion in the diagnosis of obsessive-compulsive disorder (OCD). Accordingly, the present study examined the reliability, validity, factorial structure, and diagnostic sensitivity of a revised version of the scale - the OCI-CV-R- that excludes items assessing hoarding. METHODS: Participant were 1047 youth, including 489 meeting DSM criteria for primary OCD, 298 clinical controls, and 260 nonclinical controls, who completed the OCI-CV and measures of obsessive-compulsive symptom severity, depression, and anxiety at various treatment and research centers. RESULTS: Findings support a five-factor structure (doubting/checking, obsessing, washing, ordering, and neutralizing), with a higher order factor. Factorial invariance was found for older (12-17 years) and younger (7-11 years) children. Internal consistency of the OCI-CV-R was acceptable, and discriminant and convergent validity were adequate and akin to that of its progenitor. Diagnostic sensitivity and specificity were found for a total score of 8 and higher. CONCLUSION: It is recommended that the OCI-CV-R replace the former version, and that this measure serve as part of a comprehensive clinical assessment of youth with OCD. Recommendations for further research with ethnically and racially diverse samples, as well as the need to establish benchmark scores are discussed.


Assuntos
Transtorno Obsessivo-Compulsivo , Adolescente , Ansiedade , Humanos , Transtorno Obsessivo-Compulsivo/diagnóstico , Escalas de Graduação Psiquiátrica , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
5.
Biomed Res Int ; 2021: 9996071, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34307687

RESUMO

BACKGROUND: Platelet concentrates like leucocyte- and platelet-rich fibrin (L-PRF) have been widely evaluated in different oral surgical procedures to promote the healing process. However, liquid L-PRF products such as liquid fibrinogen have been poorly explored, especially in the biomimetic functionalization of dental implants. The aim of this in vitro study is to evaluate the interaction between 5 different dental implant surfaces and liquid fibrinogen. METHODS: Five commercially available dental implants with different surfaces (Osseospeed™, TiUnite™, SLActive®, Ossean®, and Plenum®) were immersed for 60 minutes in liquid fibrinogen obtained from healthy donors. After this period, the implants were removed and fixed for scanning electron microscopy (SEM). RESULTS: All dental implants were covered by a fibrin mesh. However, noticeable noncontact areas were observed for the Osseospeed™, TiUnite™, and SLActive® surfaces. On the other hand, Ossean® and Plenum® surfaces showed a dense and uniform layer of fibrin covering almost the entire implant surface. The Osseospeed™, TiUnite™, and SLActive® surfaces presented with lower blood cell numbers inside the fibrin mesh compared with the others. Moreover, at higher magnification, thicker fibrin fibers were observed in contact with Ossean® and Plenum® surfaces. The Plenum ®surface showed the thickest fibers which also inserted and interconnect to the microroughness. CONCLUSION: The initial contact between an implant surface and the fibrin network differs significantly among different implant brands. Further studies are necessary to explore the clinical impact of these observations in the osseointegration process of dental implants.


Assuntos
Fibrinogênio/metabolismo , Implantes Dentários , Fibrina/metabolismo , Humanos , Microscopia Eletrônica de Varredura , Projetos Piloto
6.
Neurosci Biobehav Rev ; 125: 517-534, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33639178

RESUMO

Obsessive-compulsive disorder (OCD) is disabling and often treatment-refractory. Host immunity and gut microbiota have bidirectional communication with each other and with the brain. Perturbations to this axis have been implicated in neuropsychiatric disorders, but immune-microbiome signaling in OCD is relatively underexplored. We review support for further pursuing such investigations in OCD, including: 1) gut microbiota has been associated with OCD, but causal pathogenic mechanisms remain unclear; 2) early environmental risk factors for OCD overlap with critical periods of immune-microbiome development; 3) OCD is associated with increased risk of immune-mediated disorders and changes in immune parameters, which are separately associated with the microbiome; and 4) gut microbiome manipulations in animal models are associated with changes in immunity and some obsessive-compulsive symptoms. Theoretical pathogenic mechanisms could include microbiota programming of cytokine production, promotion of expansion and trafficking of peripheral immune cells to the CNS, and regulation of microglial function. Immune-microbiome signaling in OCD requires further exploration, and may offer novel insights into pathogenic mechanisms and potential treatment targets for this disabling disorder.


Assuntos
Microbioma Gastrointestinal , Microbiota , Transtorno Obsessivo-Compulsivo , Animais , Encéfalo
7.
J Psychiatr Res ; 132: 72-83, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33068817

RESUMO

Interest in the pathology of Obsessive-Compulsive Disorder\has focused on brain network profiles of the dorsal Anterior Cingulate Cortex (dACC), given its role as a principal control region. Both motor control and working memory tasks induce dysfunctional dACC profiles in OCD. H H We contrasted dACC network profiles in OCD and age-comparable controls during both tasks (from data collected in the same participants). The motor task required participants to tap their right forefinger in response to a flashing white probe; the memory task was a standard n-back (2-Back) requiring participants to identify if a current stimulus was identical to the one presented two items before it in the sequence. Network interactions were modeled using Psychophysiological Interactions (PPI), a model of directional functional connectivity. Inter-group analyses indicated a) that the motor control task evoked greater dACC modulation than the working memory task, and b) that the modulatory effect was significantly greater in the OCD group. We also investigated the relationship between OCD symptom dimensions (lifetime obsession and lifetime compulsion measured using the CY-BOCS) and dACC network profiles in OCD. This analysis revealed a dichotomy between Obsessive-Compulsive symptom dimensions and the degree of dACC modulation: primarily increased obsessions predicted increased modulation during the motor control task, but primarily increased compulsions predicted increased modulation during the working memory task. These results re-emphasize the salience of the dACC in OCD, and the primacy of tasks of motor control in evoking dACC pathology in the disorder.


Assuntos
Giro do Cíngulo , Transtorno Obsessivo-Compulsivo , Adolescente , Humanos , Imageamento por Ressonância Magnética , Memória de Curto Prazo
8.
Cereb Cortex ; 31(2): 1032-1045, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-32995843

RESUMO

The myeloarchitecture of the corpus callosum (CC) is characterized as a mosaic of distinct differences in fiber density of small- and large-diameter axons along the anterior-posterior axis; however, regional and age differences across the lifespan are not fully understood. Using multiecho T2 magnetic resonance imaging combined with multi-T2 fitting, the myelin water fraction (MWF) and geometric-mean of the intra-/extracellular water T2 (geomT2IEW) in 395 individuals (7-85 years; 41% males) were examined. The approach was validated where regional patterns along the CC closely resembled the histology; MWF matched mean axon diameter and geomT2IEW mirrored the density of large-caliber axons. Across the lifespan, MWF exhibited a quadratic association with age in all 10 CC regions with evidence of a positive linear MWF-age relationship among younger participants and minimal age differences in the remainder of the lifespan. Regarding geomT2IEW, a significant linear age × region interaction reflected positive linear age dependence mostly prominent in the regions with the highest density of small-caliber fibers-genu and splenium. In all, these two indicators characterize distinct attributes that are consistent with histology, which is a first. In addition, these results conform to rapid developmental progression of CC myelination leveling in middle age as well as age-related degradation of axon sheaths in older adults.


Assuntos
Axônios/fisiologia , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/fisiologia , Longevidade/fisiologia , Bainha de Mielina/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Contagem de Células/métodos , Contagem de Células/tendências , Criança , Corpo Caloso/citologia , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/tendências , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
J Am Acad Child Adolesc Psychiatry ; 60(6): 688-689, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33359031

RESUMO

"I'm a little bit OCD" is a common refrain on social media, usually referring to a benign tendency toward cleanliness, order, and "keeping one's eye on the prize." In truth, obsessive-compulsive disorder (OCD) is a debilitating disorder of ritual and doubt that carries a significant burden on functioning for those affected. Even subclinical OCD, which is 2-8 times more common than OCD in children, can engender considerable suffering, including social withdrawal, anxiety, depressed mood, and excess somatic complaints.1,2 It has been suggested that subclinical OCD symptoms during childhood may be precursors to developing the full disorder in adolescence and adulthood. However, the neurobiological underpinnings of subclinical OCD and their development and correlation to child functioning have not yet been well elucidated.


Assuntos
Transtorno Obsessivo-Compulsivo , Adolescente , Adulto , Ansiedade , Transtornos de Ansiedade , Criança , Família , Humanos , Neurobiologia
10.
Brain Struct Funct ; 225(3): 1089-1102, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32246244

RESUMO

Functional connectivity analyses for task-based fMRI data are generally preceded by methods for identification of network nodes. As there is no general canonical approach to identifying network nodes, different identification techniques may exert different effects on inferences drawn regarding functional network properties. Here, we compared the impact of two different node identification techniques on estimates of local node importance (based on Degree Centrality, DC) in two working memory domains: verbal and visual. The two techniques compared were the commonly used Activation Likelihood Estimate (ALE) technique (with node locations based on data aggregation), against a hybrid technique, Experimentally Derived Estimation (EDE). In the latter, ALE was first used to isolate regions of interest; then participant-specific nodes were identified based on individual-participant local maxima. Time series were extracted at each node for each dataset and subsequently used in functional connectivity analysis to: (1) assess the impact of choice of technique on estimates of DC, and (2) assess the difference between the techniques in the ranking of nodes (based on DC) in the networks they produced. In both domains, we found a significant Technique by Node interaction, signifying that the two techniques yielded networks with different DC estimates. Moreover, for the majority of participants, node rankings were uncorrelated between the two techniques (85% for the verbal working memory task and 92% for the visual working memory task). The latter effect is direct evidence that the identification techniques produced different rankings at the level of individual participants. These results indicate that node choice in task-based fMRI data exerts downstream effects that will impact interpretation and reverse inference regarding brain function.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Imageamento por Ressonância Magnética , Memória de Curto Prazo/fisiologia , Adolescente , Adulto , Interpretação Estatística de Dados , Feminino , Humanos , Funções Verossimilhança , Masculino , Metanálise como Assunto , Vias Neurais/fisiologia , Adulto Jovem
11.
Child Psychiatry Hum Dev ; 51(6): 888-899, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32030629

RESUMO

The study assessed the ability of the Obsessive-Compulsive Inventory-Child Version (OCI-CV) to detect pediatric obsessive-compulsive disorder (OCD) using receiver operating characteristic analyses. The sample consisted of 114 cases with current OCD, 340 cases with other psychiatric disorders (OPD), and 301 healthy controls (HC) ages 7 to 18 years. All 755 participants were assessed with two semi-structured interviews and seven rating scales. In a comparison of current OCD cases and all other participants, the optimal OCI-CV cut-score was 11 with an area under the curve (AUC) of .88. In a comparison of current OCD cases and OPD cases, the optimal OCI-CV cut-score was 11 with an AUC of .82. In a comparison of current OCD cases and HC, the optimal OCI-CV cut-score was 10 with an AUC of .94. The results indicate that the OCI-CV provides an effective screen for pediatric OCD using empirically derived cut-scores.


Assuntos
Programas de Rastreamento/estatística & dados numéricos , Transtorno Obsessivo-Compulsivo/diagnóstico , Inventário de Personalidade/estatística & dados numéricos , Adolescente , Criança , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Transtornos Mentais/diagnóstico , Transtornos Mentais/psicologia , Transtorno Obsessivo-Compulsivo/psicologia , Psicometria/estatística & dados numéricos , Curva ROC , Reprodutibilidade dos Testes
12.
Brain Imaging Behav ; 14(5): 1612-1625, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31187473

RESUMO

Obsessive-compulsive disorder (OCD) is phenotypically heterogeneous and genetically complex. This study aimed to reduce heterogeneity using structural brain imaging to study putative intermediate phenotypes for OCD. We hypothesized that select serotonin gene variants would differ in their relationship with brain volume in specific regions of the cortico-striato-thalamo-cortical (CSTC) circuits between OCD patients and controls. In a total of 200 pediatric subjects, we genotyped candidate serotonin genes (SLC6A4, HTR2A, HTR1B, and HTR2C) and conducted structural magnetic resonance imaging (sMRI) to measure regional brain volumes within CSTC circuits. In males and females separately, we first tested the association between serotonin gene variants and OCD and the effect of serotonin gene variants on brain volume irrespective of diagnosis. We then carried out a series of analyses to assess the effect of genotype-diagnosis interaction on brain volume. In females, but not in males, we identified a statistically significant genotype-diagnosis interaction for two single nucleotide polymorphisms (SNPs) in HTR2C, rs12860460 (interaction term estimate of 5.45 cc and interaction P value of 9.70e-8) and rs12854485 (interaction term estimate of 4.28 cc and interaction P value of 2.07e-6). The tested allele in each SNP was associated with decreased anterior cingulate cortex (ACC) volume in controls and with increased ACC volume in OCD patients. Our findings suggest that, in females, sequence variation in HTR2C influences ACC volume in pediatric OCD. The variants may contribute to differences in ACC volume and to OCD in a sex-specific manner when acting together with other genetic, biological, and/or environmental factors.


Assuntos
Transtorno Obsessivo-Compulsivo , Receptor 5-HT2C de Serotonina/genética , Serotonina , Encéfalo/diagnóstico por imagem , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina
14.
NPJ Genom Med ; 4: 26, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31602316

RESUMO

Copy number variations (CNVs) are implicated across many neurodevelopmental disorders (NDDs) and contribute to their shared genetic etiology. Multiple studies have attempted to identify shared etiology among NDDs, but this is the first genome-wide CNV analysis across autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), schizophrenia (SCZ), and obsessive-compulsive disorder (OCD) at once. Using microarray (Affymetrix CytoScan HD), we genotyped 2,691 subjects diagnosed with an NDD (204 SCZ, 1,838 ASD, 427 ADHD and 222 OCD) and 1,769 family members, mainly parents. We identified rare CNVs, defined as those found in <0.1% of 10,851 population control samples. We found clinically relevant CNVs (broadly defined) in 284 (10.5%) of total subjects, including 22 (10.8%) among subjects with SCZ, 209 (11.4%) with ASD, 40 (9.4%) with ADHD, and 13 (5.6%) with OCD. Among all NDD subjects, we identified 17 (0.63%) with aneuploidies and 115 (4.3%) with known genomic disorder variants. We searched further for genes impacted by different CNVs in multiple disorders. Examples of NDD-associated genes linked across more than one disorder (listed in order of occurrence frequency) are NRXN1, SEH1L, LDLRAD4, GNAL, GNG13, MKRN1, DCTN2, KNDC1, PCMTD2, KIF5A, SYNM, and long non-coding RNAs: AK127244 and PTCHD1-AS. We demonstrated that CNVs impacting the same genes could potentially contribute to the etiology of multiple NDDs. The CNVs identified will serve as a useful resource for both research and diagnostic laboratories for prioritization of variants.

15.
Artigo em Inglês | LILACS | ID: biblio-1003816

RESUMO

ABSTRACT: Background: Statins are drugs used for the treatment of dyslipidemia. However, statins have multiple actions, including anti-inflammatory and immunomodulatory effects, as well as the ability to stimulate new bone formation. Such features could be beneficial for periodontal pathology therapy. Methods: A literature review was conducted using filtered electronic databases (Cochrane and Trip) and unfiltered databases (Medline/PubMed, Scielo and Google Scholar). The articles chosen were controlled and randomized clinical trials that performed local delivery of statins to humans and assessed the effects of immunomodulation and bone regeneration on periodontal disease between 2010 and 2017. All of the studies were blind or double-blind and were written in English. Results: The inclusion criteria were applied to a total of 79 identified articles, and 10 studies were ultimately chosen. The results show that an injected dose of statins or the local delivery of atorvastatin (ATV) leads to a significant improvement in clinical and radiographic periodontal parameters. Moreover, rosuvastatin (RSV) induced stronger beneficial effects when administered systemically, whereas ATV and simvastatin (SMV) had better results following topical delivery. Conclusions: Statins can affect periodontal status, increasing the gain in clinical attachment and decreasing gingival bleeding, probing depth and the magnitude of bone defects. For this reason, statins represent an excellent support measure for conventional periodontal therapy. Specifically, positive effects are seen for local delivery of statins as an adjunct treatment to scaling and root planing (SRP) at doses of 1.2 to 2%. Statins could be administered through topical delivery via direct injection in the periodontal pocket or by brushing with medicated dentifrices. More studies with appropriate designs should evaluate the short and long term clinical benefit of statins inpatients with periodontal pathology. These studies should determine the appropriate dose, timing side effects and ideal vehicles for delivery.


Assuntos
Humanos , Doenças Periodontais , Terapêutica , Regeneração Óssea , Inibidores de Hidroximetilglutaril-CoA Redutases
16.
Hum Brain Mapp ; 40(5): 1458-1469, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30536968

RESUMO

Functional connectivity (FC) analysis of fMRI data typically rests on prior identification of network nodes from activation profiles. We compared Activation Likelihood Estimate (ALE) and the Experimentally Derived Estimate (EDE) approaches to network node identification and functional inference for both verbal and visual forms of working memory. ALE arrives at canonical activation maxima that are assumed to reliably represent peaks of brain activity underlying a psychological process (e.g., working memory). By comparison, EDEs of activation maxima are typically derived from individual participant data, and are thus sensitive to individual participant activation profiles. Here, nodes were localized by both ALE and EDE methods for each participant, and subsequently extracted time series were compared using connectivity analysis. Two sets of significance tests were performed: (1) correlations computed between nodal time series of each method were compared, and (2) correlations computed between network edges (functional connections) of each network node pair were compared. Large proportions of edge correlations significantly differed between methods. ALE effectively summarizes working memory network node locations across studies and subjects, but the sensitivity to individual functional loci suggest that EDE methods provide individualized estimates of network connectivity. We suggest that a hybrid method incorporating both ALE and EDE is optimal for network inference.


Assuntos
Mapeamento Encefálico/métodos , Rede Nervosa/fisiologia , Adolescente , Conectoma/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Individualidade , Funções Verossimilhança , Imageamento por Ressonância Magnética , Masculino , Memória de Curto Prazo , Rede Nervosa/diagnóstico por imagem , Aprendizagem Verbal , Percepção Visual/fisiologia , Adulto Jovem
17.
Brain Topogr ; 31(6): 985-1000, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30032347

RESUMO

We investigated the flexible modulation of undirected functional connectivity (uFC) of brain pathways during simple uni-manual responding. Two questions were central to our interests: (1) does response hand (dominant vs. non-dominant) differentially modulate connectivity and (2) are these effects related to responding under varying motor sets. fMRI data were acquired in twenty right-handed volunteers who responded with their right (dominant) or left (non-dominant) hand (blocked across acquisitions). Within acquisitions, the task oscillated between periodic responses (promoting the emergence of motor sets) or randomly induced responses (disrupting the emergence of motor sets). Conjunction analyses revealed eight shared nodes across response hand and condition, time series from which were analyzed. For right hand responses connectivity of the M1 ←→ Thalamus and SMA ←→ Parietal pathways was more significantly modulated during periodic responding. By comparison, for left hand responses, connectivity between five network pairs (including M1 and SMA, insula, basal ganglia, premotor cortex, parietal cortex, thalamus) was more significantly modulated during random responding. uFC analyses were complemented by directed FC based on multivariate autoregressive models of times series from the nodes. These results were complementary and highlighted significant modulation of dFC for SMA → Thalamus, SMA → M1, basal ganglia → Insula and basal ganglia → Thalamus. The results demonstrate complex effects of motor organization and task demand and response hand on different connectivity classes of fMRI data. The brain's sub-networks are flexibly modulated by factors related to motor organization and/or task demand, and our results have implications for assessment of medical conditions associated with motor dysfunction.


Assuntos
Encéfalo/fisiologia , Mãos , Atividade Motora/fisiologia , Adolescente , Gânglios da Base/fisiologia , Mapeamento Encefálico/métodos , Feminino , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Córtex Motor/fisiologia , Vias Neurais/fisiologia , Lobo Parietal/fisiologia , Tálamo/fisiologia , Adulto Jovem
18.
Int. j. morphol ; 35(2): 394-402, June 2017. ilus
Artigo em Inglês | LILACS | ID: biblio-892994

RESUMO

Reports indicate that statins (cholesterol-lowering drugs), in addition to lowering cholesterol, have an immunomodulatory effect. This effect may be beneficial for the treatment of several diseases, including periodontal disease. The aim of the present study was to evaluate the immunomodulatory effect of an atorvastatin-medicated dentifrice on CD4+ T cell proliferation. CD4+ T cell proliferation assays and peripheral blood mononuclear cell (PBMC) viability assays were conducted on PBMCs from healthy donors cultured under the following conditions: control, atorvastatin solution, atorvastatin-medicated dentifrice, and dentifrice without atorvastatin at concentrations of 1, 5, 10, 50 and 100 µM. A Generalized Equation Estimation (GEE) model was used to analyze concentration versus proliferation and concentration versus percentage of dead cells within each group evaluated. Atorvastatin-medicated dentifrice (p-value <0.0001) and atorvastatin solution (p-value <0.0001) significantly inhibited CD4+ T cell proliferation in a dose-dependent manner compared with the dentifrice without atorvastatin and control conditions. Only the relationship between atorvastatin solution and percentage of dead cells was significant compared to the other conditions (p-value 0.019). The results revealed that atorvastatin-medicated dentifrice at concentrations of 1 to 100 µM had immunomodulatory effects, inhibiting CD4+ T cell proliferation without affecting PBMC viability. The other components of the dentifrice did not affect CD4+ T cell proliferation or cell viability, indicating its utility as a vehicle to achieve the desired effects of atorvastatin in periodontal tissue. Controlled clinical trials are still needed to evaluate the clinical effects of an atorvastatin-medicated dentifrice on the periodontium.


La literatura indica que las estatinas (medicamentos para bajar el colesterol), además de reducir el colesterol, tienen un efecto inmunomodulador. Este efecto puede ser beneficioso para el tratamiento de varias enfermedades, incluyendo la enfermedad periodontal. El objetivo de este estudio es evaluar el efecto inmunomodulador de una pasta dental medicada con atorvastatina sobre la proliferación celular de linfocitos T CD4+. A partir de células mononucleares de sangre periférica de donantes sanos (PBMC), se realizaron ensayos de proliferación y viabilidad de linfocitos T CD4+ bajo las siguientes condiciones: control, solución de atorvastatina, dentífrico medicado con atorvastatina y dentífrico sin atorvastatina, en concentraciones 1, 5, 10, 50 and 100 µM. Se realizó el análisis estadístico utilizando el modelo Generalized Equation Estimation (GEE) a fin de analizar la concentración versus la proliferación y la concentración versus el porcentaje de muerte celular para cada uno de los grupos. El dentífrico medicado con atorvastatina (valor p <0,0001) y solución de atorvastatina (valor p <0,0001) inhibieron significativamente la proliferación de células T CD4 + de una manera dependiente de la dosis en comparación con el dentífrico sin atorvastatina y condiciones de control. Sólo la relación entre la atorvastatina solución y el porcentaje de células muertas fue significativa en comparación con las otras condiciones (vale-p 0,019). Los resultados revelaron que el dentífrico medicado con atorvastatina en concentraciones de 1 a 100 mM tenía efectos inmunomoduladores, inhibiendo la proliferación de células T CD4 + sin afectar la viabilidad de PBMC. Los otros componentes del dentífrico no afectaron la proliferación de células T CD4 + o la viabilidad celular, indicando su utilidad como vehículo para conseguir los efectos deseados de atorvastatina en el tejido periodontal. Todavía se necesitan ensayos clínicos controlados para evaluar los efectos clínicos de un dentífrico medicado con atorvastatina sobre el periodonto.


Assuntos
Periodonto/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Dentifrícios , Atorvastatina/administração & dosagem , Técnicas In Vitro , Linfócitos T CD4-Positivos/imunologia , Sobrevivência Celular/efeitos dos fármacos , Projetos Piloto , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo
19.
Psychiatry Res Neuroimaging ; 260: 6-15, 2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-27992792

RESUMO

In an effort to elucidate differences in functioning brain networks between youth with obsessive-compulsive disorder and controls, we used fMRI signals to analyze brain network interactions of the dorsal anterior cingulate cortex (dACC) during visually coordinated motor responses. Subjects made a uni-manual response to briefly presented probes, at periodic (allowing participants to maintain a "motor set") or random intervals (demanding reactive responses). Network interactions were assessed using psycho-physiological interaction (PPI), a basic model of functional connectivity evaluating modulatory effects of the dACC in the context of each task condition. Across conditions, OCD were characterized by hyper-modulation by the dACC, with loci alternatively observed as both condition-general and condition-specific. Thus, dynamically driven task demands during simple uni-manual motor control induce compensatory network interactions in cortical-thalamic regions in OCD. These findings support previous research in OCD showing compensatory network interactions during complex memory tasks, but establish that these network effects are observed during basic sensorimotor processing. Thus, these patterns of network dysfunction may in fact be independent of the complexity of tasks used to induce brain network activity. Hypothesis-driven approaches coupled with sophisticated network analyses are a highly valuable approach in using fMRI to uncover mechanisms in disorders like OCD.


Assuntos
Giro do Cíngulo/fisiopatologia , Rede Nervosa/fisiopatologia , Transtorno Obsessivo-Compulsivo/fisiopatologia , Desempenho Psicomotor/fisiologia , Adolescente , Mapeamento Encefálico , Criança , Feminino , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória , Rede Nervosa/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Adulto Jovem
20.
Psychiatry Res Neuroimaging ; 258: 30-36, 2016 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-27835798

RESUMO

There is evidence of greater cognitive deficits in attention deficit hyperactivity disorder with a comorbid reading disability (ADHD/+RD) compared to ADHD alone (ADHD/-RD). Additionally, the striatum has been consistently implicated in ADHD. However, the extent of morphological alterations in the striatum of ADHD/+RD is poorly understood, which is the main purpose of this study. Based on structural MRI images, the surface deformation of the caudate and putamen was assessed in 59 boys matching in age and IQ [19 ADHD/-RD, 15 ADHD/+RD and 25 typically developing controls (TDC)]. A vertex based analysis with multiple comparison correction was conducted to compare ADHD/-RD and ADHD/+RD to TDC. Compared to TDC, ADHD/+RD showed multiple bilateral significant clusters of surface compression. In contrast, ADHD/-RD showed fewer significant clusters of surface compression and restricted to the left side. Regarding the putamen, only ADHD/-RD showed significant clusters of surface compression. Results demonstrate for the first time a greater extent of morphological alterations in the caudate of ADHD/+RD than ADHD/-RD compared to TDC, which may suggest greater implicated cortical areas projecting to the caudate that are associated with the greater neuropsychological impairments observed in ADHD/+RD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/patologia , Corpo Estriado/patologia , Dislexia/patologia , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Criança , Corpo Estriado/diagnóstico por imagem , Dislexia/complicações , Dislexia/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Leitura
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