Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Mol Psychiatry ; 25(4): 863-872, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-30283030

RESUMO

Although schizophrenia is considered a brain disorder, the role of brain organization for symptomatic improvement remains inadequately defined. We investigated the relationship between baseline brain morphology, resting-state network connectivity and clinical response after 24-weeks of antipsychotic treatment in patients with schizophrenia (n = 95) using integrated multivariate analyses. There was no significant association between clinical response and measures of cortical thickness (r = 0.37, p = 0.98) and subcortical volume (r = 0.56, p = 0.15). By contrast, we identified a strong mode of covariation linking functional network connectivity to clinical response (r = 0.70; p = 0.04), and particularly to improvement in positive (weight = 0.62) and anxious/depressive symptoms (weight = 0.49). Higher internal cohesiveness of the default mode network was the single most important positive predictor. Key negative predictors involved the functional cohesiveness of central executive subnetworks anchored in the frontoparietal cortices and subcortical regions (including the thalamus and striatum) and the inter-network integration between the default mode and sensorimotor networks. The present findings establish links between clinical response and the functional organization of brain networks involved both in perception and in spontaneous and goal-directed cognition, thereby advancing our understanding of the pathophysiology of schizophrenia.


Assuntos
Encéfalo/fisiopatologia , Vias Neurais/fisiopatologia , Esquizofrenia/fisiopatologia , Adulto , Atenção/fisiologia , Mapeamento Encefálico/métodos , Córtex Cerebral/fisiopatologia , Cognição/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Rede Nervosa , Tálamo/fisiopatologia
2.
Neuroimage ; 185: 27-34, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30312809

RESUMO

BACKGROUND: Intracortical myelin is a key determinant of neuronal synchrony and plasticity that underpin optimal brain function. Magnetic resonance imaging (MRI) facilitates the examination of intracortical myelin but presents with methodological challenges. Here we describe a whole-brain approach for the in vivo investigation of intracortical myelin in the human brain using ultra-high field MRI. METHODS: Twenty-five healthy adults were imaged in a 7 Tesla MRI scanner using diffusion-weighted imaging and a T1-weighted sequence optimized for intracortical myelin contrast. Using an automated pipeline, T1 values were extracted at 20 depth-levels from each of 148 cortical regions. In each cortical region, T1 values were used to infer myelin concentration and to construct a non-linearity index as a measure the spatial distribution of myelin across the cortical ribbon. The relationship of myelin concentration and the non-linearity index with other neuroanatomical properties were investigated. Five patients with multiple sclerosis were also assessed using the same protocol as positive controls. RESULTS: Intracortical T1 values decreased between the outer brain surface and the gray-white matter boundary following a slope that showed a slight leveling between 50% and 75% of cortical depth. Higher-order regions in the prefrontal, cingulate and insular cortices, displayed higher non-linearity indices than sensorimotor regions. Across all regions, there was a positive association between T1 values and non-linearity indices (P < 10-5). Both T1 values (P < 10-5) and non-linearity indices (P < 10-15) were associated with cortical thickness. Higher myelin concentration but only in the deepest cortical levels was associated with increased subcortical fractional anisotropy (P = 0.05). CONCLUSIONS: We demonstrate the usefulness of an automatic, whole-brain method to perform depth-dependent examination of intracortical myelin organization. The extracted metrics, T1 values and the non-linearity index, have characteristic patterns across cortical regions, and are associated with thickness and underlying white matter microstructure.


Assuntos
Encéfalo/anatomia & histologia , Imagem de Difusão por Ressonância Magnética/métodos , Bainha de Mielina , Neuroimagem/métodos , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Bainha de Mielina/ultraestrutura
3.
Hum Brain Mapp ; 38(4): 1846-1864, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28067006

RESUMO

Functional magnetic resonance imaging (fMRI) studies in psychiatry use various tasks to identify case-control differences in the patterns of task-related brain activation. Differently activated regions are often ascribed disorder-specific functions in an attempt to link disease expression and brain function. We undertook a systematic meta-analysis of data from task-fMRI studies to examine the effect of diagnosis and study design on the spatial distribution and direction of case-control differences on brain activation. We mapped to atlas regions coordinates of case-control differences derived from 537 task-fMRI studies in schizophrenia, bipolar disorder, major depressive disorder, anxiety disorders, and obsessive compulsive disorder comprising observations derived from 21,427 participants. The fMRI tasks were classified according to the Research Domain Criteria (RDoC). We investigated whether diagnosis, RDoC domain or construct and use of regions-of-interest or whole-brain analyses influenced the neuroanatomical pattern of results. When considering all primary studies, we found an effect of diagnosis for the amygdala and caudate nucleus and an effect of RDoC domains and constructs for the amygdala, hippocampus, putamen and nucleus accumbens. In contrast, whole-brain studies did not identify any significant effect of diagnosis or RDoC domain or construct. These results resonate with prior reports of common brain structural and genetic underpinnings across these disorders and caution against attributing undue specificity to brain functional changes when forming explanatory models of psychiatric disorders. Hum Brain Mapp 38:1846-1864, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Mapeamento Encefálico , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Transtornos Mentais/diagnóstico por imagem , Estudos de Casos e Controles , Bases de Dados Bibliográficas/estatística & dados numéricos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Transtornos Mentais/classificação , Transtornos Mentais/patologia , Oxigênio/sangue
4.
Hum Brain Mapp ; 38(12): 6068-6082, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28901713

RESUMO

Interoception has been defined as the sensing of the physiological condition of the body, with interoceptive sensibility (IS) characterizing an individual's self-reported awareness of internal sensation. IS is a multidimensional construct including not only the tendency to be aware of sensation but also how sensations are interpreted, regulated, and used to inform behavior, with different dimensions relating to different aspects of health and disease. Here we investigated neural mechanisms of interoception when healthy individuals attended to their heartbeat and skin temperature, and examined the relationship between neural activity during interoception and individual differences in self-reported IS using the Multidimensional Scale of Interoceptive Awareness (MAIA). Consistent with prior work, interoception activated a network involving insula and sensorimotor regions but also including occipital, temporal, and prefrontal cortex. Differences based on interoceptive focus (heartbeat vs skin temperature) were found in insula, sensorimotor regions, occipital cortex, and limbic areas. Factor analysis of MAIA dimensions revealed 3 dissociable components of IS in our dataset, only one of which was related to neural activity during interoception. Reduced scores on the third factor, which reflected reduced ability to control attention to body sensation and increased tendency to distract from and worry about aversive sensations, was associated with greater activation in many of the same regions as those involved in interoception, including insula, sensorimotor, anterior cingulate, and temporal cortex. These data suggest that self-rated interoceptive sensibility is related to altered activation in regions involved in monitoring body state, which has implications for disorders associated with abnormality of interoception. Hum Brain Mapp 38:6068-6082, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Conscientização/fisiologia , Encéfalo/fisiologia , Interocepção/fisiologia , Sensação/fisiologia , Atenção/fisiologia , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Análise Fatorial , Humanos , Individualidade , Imageamento por Ressonância Magnética , Testes Neuropsicológicos , Autorrelato
5.
J ECT ; 29(4): e61-2, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23670023

RESUMO

We present the case of a young man with a long-standing history of schizophrenia who presented with severe and life-threatening catatonia in the setting of synthetic cannabis use who was successfully treated with electroconvulsive therapy. To our knowledge, this is the first reported case of severe and persistent catatonia in the setting of synthetic cannabis use and the first documented successful treatment.


Assuntos
Cannabis/efeitos adversos , Catatonia/terapia , Eletroconvulsoterapia , Abuso de Maconha/terapia , Esquizofrenia/terapia , Adulto , Catatonia/complicações , Drogas Desenhadas/efeitos adversos , Humanos , Masculino , Abuso de Maconha/complicações , Esquizofrenia/complicações , Resultado do Tratamento
6.
Neuropsychopharmacology ; 44(2): 390-398, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30116006

RESUMO

Several psychiatric disorders involve abnormalities of interoception and associated neural circuitry centered on the insula. The development of interventions modulating interoceptive circuits could lead to novel treatment approaches for these disorders. The 5-HT3 receptor antagonist ondansetron is a good candidate for the modulation of interoceptive circuits, as 5-HT3 receptors are located abundantly on sensory pathways and ondansetron has shown some clinical utility in disorders characterized by sensory and interoceptive abnormalities. The present study tested the ability of three different doses of ondansetron to engage neural regions involved in interoception to determine the drug's utility as a therapeutic agent to target circuit abnormalities in patients. Fifty-three healthy subjects were randomized to receive a single 8-mg (n = 18), 16-mg (n = 17), or 24-mg (n = 18) dose of ondansetron and placebo before MRI scanning on separate days. Subjects performed an fMRI task previously shown to engage interoceptive circuitry in which they viewed videos depicting body movements/sensation and control videos. The results revealed a highly significant relationship between dosage and activation in bilateral insula, somatosensory and premotor regions, cingulate cortex, and temporal cortex for control but not body-focused videos. These effects were driven by a robust reduction in activation for ondansetron compared to placebo for the 24-mg group, with weaker effects for the 16-mg and 8-mg groups. In conclusion, high-dose ondansetron reduces activation of several areas important for interoception, including insula and sensorimotor cortical regions. This study reveals the potential utility of this drug in modulating hyperactivity in these regions in patients.


Assuntos
Encéfalo/efeitos dos fármacos , Interocepção/efeitos dos fármacos , Ondansetron/farmacologia , Antagonistas da Serotonina/farmacologia , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
7.
Schizophr Res ; 201: 208-216, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29709491

RESUMO

BACKGROUND: The functional architecture of resting-state networks (RSNs) is defined by their connectivity and metastability. Disrupted RSN connectivity has been amply demonstrated in schizophrenia while the role of metastability remains poorly defined. Here, we undertake a comprehensive characterisation of RSN organization in schizophrenia and test its contribution to the clinical profile of this disorder. METHODS: We extracted RSNs representing the default mode (DMN), central executive (CEN), salience (SAL), language (LAN), sensorimotor (SMN), auditory (AN) and visual (VN) networks from resting-state functional magnetic resonance imaging data obtained from patients with schizophrenia (n = 85) and healthy individuals (n = 48). For each network, we computed its functional cohesiveness and integration and used the Kuramoto order parameter to compute metastability. We used stepwise multiple regression analyses to test these RSN features as predictors of symptom severity in patients. RESULTS: RSN features respectively explained 14%, 17%, 12% and 5% of the variance in positive, negative, anxious/depressive and agitation/disorganization symptoms. Lower functional integration between the DMN, CEN and SMN primarily contributed to positive symptoms. The functional properties of the SAL network were key predictors of all other symptom dimensions; specifically, lower cohesiveness of the SAL, lower integration of this network with the LAN and higher integration with the CEN respectively contributed to negative, anxious/depressive and disorganization symptoms. Increased SAL metastability was associated with negative symptoms. CONCLUSIONS: These results confirm the primacy of the SAL network for schizophrenia and demonstrate that abnormalities in RSN connectivity and metastability are significant predictors of schizophrenia-related psychopathology.


Assuntos
Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Esquizofrenia/diagnóstico por imagem , Psicologia do Esquizofrênico , Adulto , Encéfalo/fisiopatologia , Mapeamento Encefálico , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Prognóstico , Escalas de Graduação Psiquiátrica , Descanso , Esquizofrenia/fisiopatologia , Índice de Gravidade de Doença
8.
JAMA Psychiatry ; 75(4): 386-395, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29516092

RESUMO

Importance: Alterations in multiple neuroimaging phenotypes have been reported in psychotic disorders. However, neuroimaging measures can be influenced by factors that are not directly related to psychosis and may confound the interpretation of case-control differences. Therefore, a detailed characterization of the contribution of these factors to neuroimaging phenotypes in psychosis is warranted. Objective: To quantify the association between neuroimaging measures and behavioral, health, and demographic variables in psychosis using an integrated multivariate approach. Design, Setting, and Participants: This imaging study was conducted at a university research hospital from June 26, 2014, to March 9, 2017. High-resolution multimodal magnetic resonance imaging data were obtained from 100 patients with schizophrenia, 40 patients with bipolar disorder, and 50 healthy volunteers; computed were cortical thickness, subcortical volumes, white matter fractional anisotropy, task-related brain activation (during working memory and emotional recognition), and resting-state functional connectivity. Ascertained in all participants were nonimaging measures pertaining to clinical features, cognition, substance use, psychological trauma, physical activity, and body mass index. The association between imaging and nonimaging measures was modeled using sparse canonical correlation analysis with robust reliability testing. Main Outcomes and Measures: Multivariate patterns of the association between nonimaging and neuroimaging measures in patients with psychosis and healthy volunteers. Results: The analyses were performed in 92 patients with schizophrenia (23 female [25.0%]; mean [SD] age, 27.0 [7.6] years), 37 patients with bipolar disorder (12 female [32.4%]; mean [SD] age, 27.5 [8.1] years), and 48 healthy volunteers (20 female [41.7%]; mean [SD] age, 29.8 [8.5] years). The imaging and nonimaging data sets showed significant covariation (r = 0.63, P < .001), which was independent of diagnosis. Among the nonimaging variables examined, age (r = -0.53), IQ (r = 0.36), and body mass index (r = -0.25) were associated with multiple imaging phenotypes; cannabis use (r = 0.23) and other substance use (r = 0.33) were associated with subcortical volumes, and alcohol use was associated with white matter integrity (r = -0.15). Within the multivariate models, positive symptoms retained associations with the global neuroimaging (r = -0.13), the cortical thickness (r = -0.22), and the task-related activation variates (r = -0.18); negative symptoms were mostly associated with measures of subcortical volume (r = 0.23), and depression/anxiety was associated with measures of white matter integrity (r = 0.12). Conclusions and Relevance: Multivariate analyses provide a more accurate characterization of the association between brain alterations and psychosis because they enable the modeling of other key factors that influence neuroimaging phenotypes.


Assuntos
Transtorno Bipolar/diagnóstico por imagem , Transtorno Bipolar/psicologia , Imagem Multimodal/estatística & dados numéricos , Neuroimagem/estatística & dados numéricos , Fenótipo , Esquizofrenia/diagnóstico por imagem , Psicologia do Esquizofrênico , Adulto , Transtornos de Ansiedade/diagnóstico por imagem , Transtornos de Ansiedade/fisiopatologia , Transtornos de Ansiedade/psicologia , Transtorno Bipolar/fisiopatologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Mapeamento Encefálico , Transtorno Depressivo/diagnóstico por imagem , Transtorno Depressivo/fisiopatologia , Transtorno Depressivo/psicologia , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Estilo de Vida , Masculino , Testes Neuropsicológicos , Tamanho do Órgão/fisiologia , Esquizofrenia/fisiopatologia , Substância Branca/diagnóstico por imagem , Substância Branca/fisiopatologia , Adulto Jovem
9.
Bioinformatics ; 22(19): 2437-8, 2006 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16740623

RESUMO

UNLABELLED: PROBER is an oligonucleotide primer design software application that designs multiple primer pairs for generating PCR probes useful for fluorescence in situ hybridization (FISH). PROBER generates Tiling Oligonucleotide Probes (TOPs) by masking repetitive genomic sequences and delineating essentially unique regions that can be amplified to yield small (100-2000 bp) DNA probes that in aggregate will generate a single, strong fluorescent signal for regions as small as a single gene. TOPs are an alternative to bacterial artificial chromosomes (BACs) that are commonly used for FISH but may be unstable, unavailable, chimeric, or non-specific to small (10-100 kb) genomic regions. PROBER can be applied to any genomic locus, with the limitation that the locus must contain at least 10 kb of essentially unique blocks. To test the software, we designed a number of probes for genomic amplifications and hemizygous deletions that were initially detected by Representational Oligonucleotide Microarray Analysis of breast cancer tumors. AVAILABILITY: http://prober.cshl.edu


Assuntos
Algoritmos , Mapeamento Cromossômico/métodos , Sondas de DNA/genética , Hibridização in Situ Fluorescente/métodos , Análise de Sequência de DNA/métodos , Software , Sequência de Bases , Desenho Assistido por Computador , Desenho de Equipamento , Hibridização in Situ Fluorescente/instrumentação , Dados de Sequência Molecular , Alinhamento de Sequência/métodos
11.
Genome Res ; 16(12): 1465-79, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17142309

RESUMO

Representational Oligonucleotide Microarray Analysis (ROMA) detects genomic amplifications and deletions with boundaries defined at a resolution of approximately 50 kb. We have used this technique to examine 243 breast tumors from two separate studies for which detailed clinical data were available. The very high resolution of this technology has enabled us to identify three characteristic patterns of genomic copy number variation in diploid tumors and to measure correlations with patient survival. One of these patterns is characterized by multiple closely spaced amplicons, or "firestorms," limited to single chromosome arms. These multiple amplifications are highly correlated with aggressive disease and poor survival even when the rest of the genome is relatively quiet. Analysis of a selected subset of clinical material suggests that a simple genomic calculation, based on the number and proximity of genomic alterations, correlates with life-table estimates of the probability of overall survival in patients with primary breast cancer. Based on this sample, we generate the working hypothesis that copy number profiling might provide information useful in making clinical decisions, especially regarding the use or not of systemic therapies (hormonal therapy, chemotherapy), in the management of operable primary breast cancer with ostensibly good prognosis, for example, small, node-negative, hormone-receptor-positive diploid cases.


Assuntos
Neoplasias da Mama/genética , Rearranjo Gênico , Genoma Humano , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , DNA de Neoplasias/genética , Diploide , Feminino , Amplificação de Genes , Dosagem de Genes , Perfilação da Expressão Gênica , Genômica , Humanos , Hibridização in Situ Fluorescente , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA