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1.
Bipolar Disord ; 21(6): 503-513, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31025452

RESUMO

OBJECTIVES: Bipolar disorder is marked by progressive symptomatic changes, which have been linked with episode-related structural findings-particularly in the prefrontal cortex. However, few studies have examined neurofunctional and neurochemical effects of disease burden. In this study, we compared first- and multi-episode bipolar individuals. We hypothesized that the latter would demonstrate evidence of neurophysiological differences consistent with a model of progressive functional degradation of these networks. METHODS: First- and multi-episode manic bipolar subjects participated in functional magnetic resonance imaging (fMRI) including a continuous performance task with emotional distractors, and in single-voxel (1 H) magnetic resonance spectroscopy (MRS). A priori fMRI regions-of-interest (ROI) included structures comprising prefrontal-striatal-amygdala networks; (1 H)MRS voxels were placed within bilateral ventrolateral prefrontal (VLPFC) and anterior cingulate cortex (ACC). Both ROI and voxel-based brain activation in response to emotional stimuli, and neurochemical concentrations derived from (1 H)MRS were compared across bipolar groups. RESULTS: Multi-episode bipolar subjects showed relatively lower regional activation across prefrontal-striatal-amygdala networks, including bilateral VLPFC, orbitofrontal cortex, ACC, putamen, caudate, and amygdala. Exploratory whole-brain, voxel-based analysis suggested additional areas of lower activation extending into Brodmann area 22, posterior parietal regions, and right thalamus. Glutamate and N-acetylaspartate (NAA) concentrations were also relatively lower in the ACC of multi-episode subjects. CONCLUSIONS: Disease burden, exemplified by multiple affective episodes is associated with evidence of widespread decrements in affective network activity. Lower ACC NAA concentration is similarly consistent with a model of progressive functional deficits. These findings support the functional significance of previously observed progressive structural changes throughout these regions.

2.
Bipolar Disord ; 21(4): 330-341, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30864200

RESUMO

OBJECTIVES: To investigate neurochemical abnormalities in the left and right ventrolateral prefrontal cortex (VLPFC) and anterior cingulate cortex (ACC) of youth at risk for bipolar disorder using proton magnetic resonance spectroscopy before and after their first mood episode. METHODS: Children and adolescents offspring of parents with bipolar I disorder (at-risk group, n = 117) and matched healthy controls (HC group, n = 61) were recruited at the University of Cincinnati. At-risk subjects had no lifetime major mood and psychotic disorders at baseline, and were followed up every 4 months to monitor for development of a major depressive, manic, hypomanic, or mixed mood episode. Levels of N-acetyl-aspartate (NAA), phosphocreatine plus creatine (PCr + Cr), choline-containing compounds, myo-inositol, and glutamate were determined using LCModel and corrected for partial volume effects. RESULTS: There were no baseline differences in metabolite levels for any of the brain regions between at-risk and HC youth. Nineteen at-risk subjects developed a first mood episode during follow-up. Survival analyses showed that baseline PCr + Cr levels in the left VLPFC significantly predicted a mood episode during follow-up in the at-risk group (HR: 0.47, 95% CI: 0.27-0.82, P = 0.008). There were no longitudinal changes in metabolites levels in the VLPFC and ACC before and after a mood episode in at-risk subjects. CONCLUSIONS: We found no evidence for abnormal proton spectroscopy metabolite levels in the VLPFC and ACC of at-risk youth, prior and after the development of their first mood episode. Preliminary findings of association between baseline PCr + Cr levels in the left VLPFC and risk to develop a mood episode warrant further investigation.

3.
Bipolar Disord ; 19(4): 259-272, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28574156

RESUMO

OBJECTIVES: Individualized treatment for bipolar disorder based on neuroimaging treatment targets remains elusive. To address this shortcoming, we developed a linguistic machine learning system based on a cascading genetic fuzzy tree (GFT) design called the LITHium Intelligent Agent (LITHIA). Using multiple objectively defined functional magnetic resonance imaging (fMRI) and proton magnetic resonance spectroscopy (1 H-MRS) inputs, we tested whether LITHIA could accurately predict the lithium response in participants with first-episode bipolar mania. METHODS: We identified 20 subjects with first-episode bipolar mania who received an adequate trial of lithium over 8 weeks and both fMRI and 1 H-MRS scans at baseline pre-treatment. We trained LITHIA using 18 1 H-MRS and 90 fMRI inputs over four training runs to classify treatment response and predict symptom reductions. Each training run contained a randomly selected 80% of the total sample and was followed by a 20% validation run. Over a different randomly selected distribution of the sample, we then compared LITHIA to eight common classification methods. RESULTS: LITHIA demonstrated nearly perfect classification accuracy and was able to predict post-treatment symptom reductions at 8 weeks with at least 88% accuracy in training and 80% accuracy in validation. Moreover, LITHIA exceeded the predictive capacity of the eight comparator methods and showed little tendency towards overfitting. CONCLUSIONS: The results provided proof-of-concept that a novel GFT is capable of providing control to a multidimensional bioinformatics problem-namely, prediction of the lithium response-in a pilot data set. Future work on this, and similar machine learning systems, could help assign psychiatric treatments more efficiently, thereby optimizing outcomes and limiting unnecessary treatment.


Assuntos
Sintomas Comportamentais , Transtorno Bipolar , Resistência a Medicamentos , Compostos de Lítio , Imagem por Ressonância Magnética/métodos , Espectroscopia de Prótons por Ressonância Magnética/métodos , Adolescente , Adulto , Antimaníacos/administração & dosagem , Antimaníacos/efeitos adversos , Inteligência Artificial , Sintomas Comportamentais/diagnóstico , Sintomas Comportamentais/tratamento farmacológico , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/psicologia , Manual Diagnóstico e Estatístico de Transtornos Mentais , Monitoramento de Medicamentos/métodos , Feminino , Lógica Fuzzy , Humanos , Compostos de Lítio/administração & dosagem , Compostos de Lítio/efeitos adversos , Masculino , Imagem Multimodal/métodos , Projetos Piloto , Valor Preditivo dos Testes , Prognóstico
4.
Bipolar Disord ; 18(6): 490-501, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27647671

RESUMO

OBJECTIVES: We tested the hypothesis that, with treatment, functional magnetic resonance imaging (fMRI) regional brain activation in first-episode mania would normalize - i.e., that differences from healthy subjects would diminish over time, and would be associated with clinical remission status, potentially identifying neuroanatomic treatment response markers. METHODS: Forty-two participants with bipolar I disorder were recruited during their first manic episode, pseudo-randomized to open-label lithium or quetiapine, and followed for 8 weeks. fMRI scans were obtained at baseline and then after 1 and 8 weeks of treatment, while participants performed a continuous performance task with emotional distracters. Healthy participants received fMRI scans at these same intervals. Specific region-of-interest (ROI) activations within prefrontal emotional networks were assessed as potential measures of treatment response. RESULTS: ROI data were reduced using exploratory factor analysis, which identified five factors that were organizationally consistent with functional anatomic models of human emotion modulation. Half of the participants with bipolar disorder achieved remission by Week 8 and were contrasted with the other half that did not. Analyses demonstrated that, in the bipolar disorder group in general, treatment led to decreases in activation across brain regions toward healthy subject values. However, differences in activation changes were observed between subjects with bipolar disorder who did or did not achieve remission in subcortical and amygdala factors. CONCLUSIONS: These findings provide evidence for potential neuroanatomic treatment response markers in first-episode bipolar disorder.


Assuntos
Tonsila do Cerebelo , Transtorno Bipolar , Lítio/uso terapêutico , Imagem por Ressonância Magnética/métodos , Fumarato de Quetiapina/uso terapêutico , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiopatologia , Antimaníacos/uso terapêutico , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/psicologia , Transtorno Bipolar/terapia , Emoções/fisiologia , Cuidado Periódico , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Análise e Desempenho de Tarefas , Resultado do Tratamento
5.
Nutr Neurosci ; 19(4): 145-55, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-24915543

RESUMO

OBJECTIVE: To use proton magnetic resonance spectroscopy ((1)H MRS) to investigate the effects of fish oil (FO) supplementation on cortical metabolite concentrations in adolescents with major depressive disorder (MDD). METHODS: Metabolite concentrations were determined by (1)H MRS in the anterior cingulate cortex and bilateral dorsolateral prefrontal cortex (DLPFC) of adolescents with MDD before and following 10-week open-label supplementation with low (2.4 g/day, n = 7) or high (16.2 g/day, n = 7) dose FO. Depressive symptom severity scores and erythrocyte fatty acid levels were also determined. RESULTS: Baseline erythrocyte eicosapentaenoic acid (EPA) composition was positively correlated, and arachidonic acid (AA) and the AA/EPA ratio were inversely correlated, with choline (Cho) concentrations in the right DLPFC. Docosahexaenoic acid (DHA) composition was inversely correlated with myo-inositol (mI) concentrations in the left DLPFC. Erythrocyte EPA and DHA composition increased, and AA decreased, significantly following low-dose and high-dose FO supplementation. In the intent-to-treat sample, depressive symptom severity scores decreased significantly in the high-dose group (-40%, P < 0.0001) and there was a trend in the low-dose group (-20%, P = 0.06). There were no significant baseline-endpoint changes in metabolite levels in each voxel. In the low-dose group there were changes with large effect sizes, including a decrease in mI in the left DLPFC (-12%, P = 0.18, d = 0.8) and increases in glutamate + glutamine (Glx) (+12%, P = 0.19, d = 0.8) and Cho (+15%, P = 0.08, d = 1.2) in the right DLPFC. In the high-dose group, there was a trend for increases in Cho in the right DLPFC (+10%, P = 0.09, d = 1.2). DISCUSSION: These preliminary data suggest that increasing the LCn-3 fatty acid status of adolescent MDD patients is associated with subtle changes in Glx, mI, and Cho concentrations in the DLPFC that warrant further evaluation in a larger controlled trial.


Assuntos
Fenômenos Fisiológicos da Nutrição do Adolescente , Deficiências Nutricionais/dietoterapia , Transtorno Depressivo Maior/prevenção & controle , Suplementos Nutricionais , Ácidos Graxos Essenciais/uso terapêutico , Óleos de Peixe/uso terapêutico , Adolescente , Adulto , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Deficiências Nutricionais/metabolismo , Deficiências Nutricionais/fisiopatologia , Deficiências Nutricionais/psicologia , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/etiologia , Transtorno Depressivo Maior/metabolismo , Manual Diagnóstico e Estatístico de Transtornos Mentais , Ácidos Graxos Essenciais/deficiência , Ácidos Graxos Essenciais/metabolismo , Feminino , Óleos de Peixe/administração & dosagem , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/metabolismo , Humanos , Análise de Intenção de Tratamento , Perda de Seguimento , Imagem por Ressonância Magnética , Masculino , Neuroimagem , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/metabolismo , Escalas de Graduação Psiquiátrica , Adulto Jovem
6.
J Dual Diagn ; 10(1): 39-43, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24729763

RESUMO

OBJECTIVE: Bipolar and cannabis use disorders commonly co-occur during adolescence, and neurochemical studies may help clarify the pathophysiology underlying this co-occurrence. This study compared metabolite concentrations in the left ventral lateral prefrontal cortex among adolescents with bipolar disorder (bipolar group; n = 14), adolescents with a cannabis use disorder (cannabis use group; n = 13), adolescents with cannabis use and bipolar disorders (bipolar and cannabis group; n = 25), and healthy adolescents (healthy controls; n = 15). We hypothesized that adolescents with bipolar disorder (with or without cannabis use disorder) would have decreased N-acetyl aspartate levels in the ventral lateral prefrontal cortex compared to the other groups and that the bipolar and cannabis group would have the lowest N-acetyl aspartate levels of all groups. METHODS: N-acetyl aspartate concentrations in the left ventral lateral prefrontal cortex were obtained using proton magnetic resonance spectroscopy. RESULTS: Adolescents with bipolar disorder showed significantly lower left ventral lateral prefrontal cortex N-acetyl aspartate levels, but post hoc analyses indicated that this was primarily due to increased N-acetyl aspartate levels in the cannabis group. The cannabis use disorder group had significantly higher N-acetyl aspartate levels compared to the bipolar disorder and the bipolar and cannabis groups (p = .0002 and p = .0002, respectively). Pearson correlations revealed a significant positive correlation between amount of cannabis used and N-acetyl aspartate concentrations. CONCLUSIONS: Adolescents with cannabis use disorder showed higher levels of N-acetyl aspartate concentrations that were significantly positively associated with the amount of cannabis used; however, this finding was not present in adolescents with comorbid bipolar disorder.


Assuntos
Ácido Aspártico/análogos & derivados , Transtorno Bipolar/complicações , Transtorno Bipolar/metabolismo , Abuso de Maconha/complicações , Abuso de Maconha/metabolismo , Córtex Pré-Frontal/metabolismo , Adolescente , Adulto , Ácido Aspártico/análise , Feminino , Humanos , Masculino , Espectroscopia de Prótons por Ressonância Magnética , Adulto Jovem
7.
Psychiatry Res ; 213(3): 230-4, 2013 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-23810640

RESUMO

Although brain lactate levels are typically low and difficult to measure, a few previous investigators have reported that brain lactate levels are elevated in patients with bipolar disorder. The present study investigated the distribution of lactate in bipolar and healthy brains using 2D proton magnetic resonance spectroscopic imaging on a 4-Tesla magnetic resonance imaging system. Ratios of the concentration of lactate to N-acetylaspartate, and of lactate to total creatine, were significantly higher in bipolar than in healthy subjects. Lactate signals were primarily localized to the bipolar subjects' caudate and anterior cingulate cortices, components of the frontal-subcortical circuit, suggesting that affective dysregulation may be related to metabolic abnormalities in this network.


Assuntos
Transtorno Bipolar/patologia , Ácido Láctico/metabolismo , Adolescente , Adulto , Análise de Variância , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Transtorno Bipolar/tratamento farmacológico , Colina/metabolismo , Creatina/metabolismo , Feminino , Humanos , Imagem por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Escalas de Graduação Psiquiátrica , Adulto Jovem
8.
J Clin Psychopharmacol ; 33(4): 528-32, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23764689

RESUMO

Although the neurophysiology underlying pharmacotherapy for bipolar disorder remains poorly understood, recent studies suggest that therapeutic mechanisms may be reflected in changes in concentrations of N-acetylaspartate (NAA), a putative measure of neuronal integrity and metabolism. In this study, we used magnetic resonance spectroscopy (MRS) to examine prefrontal NAA in patients receiving quetiapine for bipolar mania. On the basis of previous findings, we hypothesized that remission would be associated with increased NAA concentrations in the prefrontal cortex. Thirty-one manic bipolar patients and 13 healthy subjects were recruited to participate in this prospective study. All subjects participated in MRS at baseline and after 8 weeks of treatment. Bipolar subjects received open-label quetiapine monotherapy (mean dose [SD], 584 [191] mg). Fourteen patients remitted (Young Mania Rating Scale ≤ 12) ("remitters"), 11 patients did not ("nonremitters"), and 6 patients were lost to follow-up. Bipolar and healthy subjects did not significantly differ in baseline NAA or degree of change during the 8 weeks. Remitters showed greater mean baseline NAA concentrations in the right ventrolateral prefrontal cortex compared with nonremitters (P < 0.05). In the anterior cingulate, remitters showed near significantly decreased baseline NAA concentrations at baseline (P < 0.06), and significant differences in NAA change during the 8 weeks of treatment (P < 0.03). Manic patients who remitted with quetiapine treatment in the course of this study exhibited distinct patterns of baseline prefrontal NAA concentration, coupled with decreased NAA in the anterior cingulate with treatment; the latter possibly reflecting disparate effects of quetiapine on neuronal metabolism. These data support suggestions that therapeutic effects of quetiapine involve metabolic effects on specific prefrontal regions.


Assuntos
Antipsicóticos/uso terapêutico , Ácido Aspártico/análogos & derivados , Transtorno Bipolar/tratamento farmacológico , Dibenzotiazepinas/uso terapêutico , Espectroscopia de Ressonância Magnética , Córtex Pré-Frontal/efeitos dos fármacos , Adolescente , Adulto , Ácido Aspártico/metabolismo , Biomarcadores/metabolismo , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/metabolismo , Transtorno Bipolar/psicologia , Estudos de Casos e Controles , Feminino , Giro do Cíngulo/efeitos dos fármacos , Giro do Cíngulo/metabolismo , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/metabolismo , Estudos Prospectivos , Fumarato de Quetiapina , Indução de Remissão , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
9.
Neuropsychobiology ; 67(4): 224-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23635944

RESUMO

BACKGROUND/AIMS: This study used proton magnetic resonance spectroscopy (¹H MRS) to evaluate the neurochemistry of the anterior cingulate cortex (ACC) in adolescents with generalized anxiety disorder (GAD). METHODS: Adolescents with GAD (n = 10) and healthy subjects (n = 10) underwent a ¹H MRS scan at 4 T. Glutamate (Glu), N-acetyl aspartate, creatine (Cr) and myo-inositol concentrations were measured in the ACC and were compared between untreated adolescents with GAD and age- and sex-matched healthy subjects. RESULTS: Glu/Cr ratios in the ACC correlated with the severity of both generalized anxiety symptoms on the Pediatric Anxiety Rating Scale and with total anxiety symptom severity as measured by the Hamilton Anxiety Rating Scale, but did not differ between adolescents with GAD and healthy subjects. In addition, no differences in N-acetyl aspartate, Cr, or myo-inositol were detected between groups. CONCLUSION: These findings suggest that Glu/Cr in untreated adolescents with GAD may relate to the severity of anxiety symptoms and raise the possibility that dysregulation of Glu within the ACC may be linked to the pathophysiology of pediatric GAD.


Assuntos
Transtornos de Ansiedade/metabolismo , Ácido Aspártico/análogos & derivados , Química Encefálica , Creatina/metabolismo , Ácido Glutâmico/metabolismo , Giro do Cíngulo/metabolismo , Inositol/metabolismo , Adolescente , Ácido Aspártico/análise , Ácido Aspártico/metabolismo , Estudos de Casos e Controles , Criança , Creatina/análise , Feminino , Ácido Glutâmico/análise , Giro do Cíngulo/química , Humanos , Inositol/análise , Espectroscopia de Ressonância Magnética , Masculino , Projetos Piloto
10.
Nutr Neurosci ; 16(4): 183-90, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23582513

RESUMO

Docosahexaenoic acid (DHA, 22:6n-3) is the principal omega-3 fatty acid in mammalian brain gray matter, and emerging preclinical evidence suggests that DHA has neurotrophic and neuroprotective properties. This study investigated relationships among DHA status, neurocognitive performance, and cortical metabolism measured with proton magnetic resonance spectroscopy (1H MRS) in healthy developing male children (aged 8-10 years, n = 38). Subjects were segregated into low-DHA (n = 19) and high-DHA (n = 19) status groups by a median split of erythrocyte DHA levels. Group differences in 1H MRS indices of cortical metabolism, including choline (Cho), creatine (Cr), glutamine + glutamate + γ-aminobutyric acid (Glx), myo-inositol (mI), and n-acetyl aspartate (NAA), were determined in the right and left dorsolateral prefrontal cortex (R/L-DLPFC, BA9) and bilateral anterior cingulate cortex (ACC, BA32/33). Group differences in neurocognitive performance were evaluated with the Kaufman Brief Intelligence Test and identical-pairs version of the continuous performance task (CPT-IP). Subjects in the low-DHA group consumed fish less frequently (P = 0.02), had slower reaction times on the CPT-IP (P = 0.007), and exhibited lower mI (P = 0.007), NAA (P = 0.007), Cho (P = 0.009), and Cr (P = 0.01) concentrations in the ACC compared with the high-DHA group. There were no group differences in ACC Glx or any metabolite in the L-DLPFC and R-DLPFC. These data indicate that low-DHA status is associated with reduced indices of metabolic function in the ACC and slower reaction time during sustained attention in developing male children.


Assuntos
Ácidos Docosa-Hexaenoicos/sangue , Giro do Cíngulo/fisiopatologia , Espectroscopia de Ressonância Magnética/métodos , Estado Nutricional , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análise , Atenção/efeitos dos fármacos , Criança , Colina/análise , Cromatografia Gasosa , Creatina/análise , Humanos , Inositol/análise , Testes de Inteligência , Masculino , Tempo de Reação/efeitos dos fármacos , Fatores Socioeconômicos , Inquéritos e Questionários , Ácido gama-Aminobutírico/análise
11.
Depress Anxiety ; 30(9): 842-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23495075

RESUMO

BACKGROUND: Despite recent data implicating functional abnormalities in the neurocircuitry underlying emotional processing in pediatric anxiety disorders, little is known regarding neurostructural abnormalities within these systems. METHODS: Using voxel-based morphometry, gray and white matter volumes were compared in 15 medication-free adolescents with generalized anxiety disorder (GAD; and no comorbid major depressive disorder) and 28 age- and sex-matched healthy comparison subjects. RESULTS: Compared to healthy adolescents, youth with GAD had larger gray matter volumes in the right precuneus and right precentral gyrus and decreased gray matter volumes in the left orbital gyrus and posterior cingulate. White matter volumes were decreased in the left medial and superior frontal gyrus and were increased in the left inferior temporal gyrus in youth with GAD relative to healthy subjects. CONCLUSIONS: Adolescents with GAD, who are early in the course of their illness, exhibit abnormalities in neural structures that subserve threat appraisal, modulation of fear responses, attachment, and mentalization.


Assuntos
Transtornos de Ansiedade/patologia , Encéfalo/patologia , Fibras Nervosas Mielinizadas/patologia , Fibras Nervosas Amielínicas/patologia , Adolescente , Mapeamento Encefálico , Estudos de Casos e Controles , Criança , Feminino , Lobo Frontal/patologia , Giro do Cíngulo/patologia , Humanos , Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Masculino , Tamanho do Órgão , Lobo Parietal/patologia , Lobo Temporal/patologia
12.
MAGMA ; 26(3): 337-43, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23053715

RESUMO

OBJECT: The relative amounts of choline (Cho), phosphocholine (PC), and glycerophosphocholine (GPC) may be sensitive indicators of breast cancer and the degree of malignancy. Here we implement some simple modifications to a previously developed (1)H NMR analysis of fine-needle-aspirate (FNA) biopsies designed to yield sufficient spectral resolution of Cho, PC, and GPC for usable relative quantitation of these metabolites. MATERIALS AND METHODS: FNA biopsies of eighteen breast lesions were examined using our modified procedure for direct (1)H NMR at 400 MHz. Resonances of choline metabolites and potential interferences were fit using the computer program NUTS. RESULTS: Quantitation of PC, GPC, and Cho relative to each other and to (phospho)creatine was obtained for eleven confirmed cases of infiltrating ductal carcinoma. Reliable results could not be obtained for the remaining cases primarily due to interference from lidocaine anesthetic. CONCLUSION: Some simple modifications of a previously developed (1)H NMR analysis of FNAs yielded sufficient spectral resolution of Cho, PC, and GPC to permit usable relative quantitation at 400 MHz. In 9 of the 11 quantified cases the sum of GPC and Cho exceeded 42 % of the total choline-metabolite peak area.


Assuntos
Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Biópsia por Agulha Fina/métodos , Neoplasias da Mama/metabolismo , Colina/análise , Colina/metabolismo , Diagnóstico por Computador/métodos , Neoplasias da Mama/patologia , Feminino , Humanos , Prótons , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
J Child Adolesc Psychopharmacol ; 22(4): 261-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22849427

RESUMO

OBJECTIVE: Mood stabilizers have been reported to affect brain concentrations of myo-inositol (mI) and N-acetylaspartate (NAA). We examined the effects of quetiapine (QUET), an atypical antipsychotic, on these neurochemicals, and potential predictors of response to QUET in adolescents with bipolar depression. METHODS: Twenty-six adolescents with bipolar depression participated in an 8-week placebo-controlled trial of QUET monotherapy. Subjects were scanned at baseline and after 8 weeks with proton magnetic resonance spectroscopy (1H-MRS) at 3T and 4T at two sites, with 8 cm(3) voxels placed in the right and left dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex (ACC). LCModel was used to calculate absolute concentrations of NAA and mI. RESULTS: Twenty-six subjects had pre- and posttreatment scans (mean age=15.6 years, 9 boys). Of these subjects, 5 out of 16 subjects receiving QUET and 5 out of 10 receiving placebo (PBO) were responders (50% decrease in Children's Depression Rating Scale [CDRS] score). Although baseline ACC mI did not predict responder status, responders had significantly lower posttreatment ACC mI values than did nonresponders (3.27±.71 vs. 4.23±.70; p=0.004). There were no significant differences in the changes in ACC and DLPFC NAA levels in the QUET group compared with the PBO group (ACC: -0.55±1.3 vs.+0.25±1.5, p=0.23; right-DLPFC: -0.55±1.3 vs. 0.33±0.89, p=0.13; left-DLPFC: -0.04±0.91 vs.+0.29±0.61, p=0.41). CONCLUSION: We found that posttreatment, not baseline, ACC mI levels were associated with response to QUET in adolescents with bipolar depression. There were no differences in NAA concentration changes between the QUET and PBO groups. Larger studies including different brain regions would help to clarify the effects of QUET on neurochemistry in patients with bipolar disorder.


Assuntos
Antipsicóticos/farmacologia , Transtorno Bipolar/tratamento farmacológico , Dibenzotiazepinas/farmacologia , Inositol/metabolismo , Adolescente , Antipsicóticos/uso terapêutico , Ácido Aspártico/análogos & derivados , Ácido Aspártico/efeitos dos fármacos , Ácido Aspártico/metabolismo , Criança , Dibenzotiazepinas/uso terapêutico , Feminino , Giro do Cíngulo/efeitos dos fármacos , Giro do Cíngulo/metabolismo , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Escalas de Graduação Psiquiátrica , Fumarato de Quetiapina , Resultado do Tratamento
14.
Magn Reson Med ; 68(2): 363-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22692991

RESUMO

This work demonstrates the first whole brain "high spatial resolution" (7)Li MR spectroscopy imaging in bipolar disorder subjects. The in vivo quantification is validated by a phantom containing 5 mM lithium salt using the identical radiofrequency sequence and imaging protocol. This study is the first demonstration of the (7)Li distribution in the brain of bipolar disorder patients on lithium therapy using a 3D MR spectroscopy imaging approach. The results show that brain lithium level is strongly correlated with serum lithium concentration. The brain-to-serum lithium ratios for the average brain and the local maximum were 0.39 ± 0.08 (r = 0.93) and 0.92 ± 0.16 (r = 0.90), respectively. The lithium distribution is found to be nonuniform throughout the brain for all patients, which is somewhat unexpected and highly intriguing. This uneven distribution is more evident in subjects at a higher therapeutic serum lithium level. This finding may suggest that lithium targets specific brain tissues and/or certain enzymatic and macromolecular sites that are associated with therapeutic effect. Further investigations of bipolar disorder patients on lithium therapy using 3D (7)Li MR spectroscopy imaging are warranted.


Assuntos
Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/metabolismo , Encéfalo/metabolismo , Imagem Tridimensional/métodos , Compostos de Lítio/farmacocinética , Compostos de Lítio/uso terapêutico , Espectroscopia de Ressonância Magnética/métodos , Adulto , Transtorno Bipolar/patologia , Encéfalo/patologia , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Distribuição Tecidual
15.
J Am Acad Child Adolesc Psychiatry ; 51(6): 642-51, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22632623

RESUMO

OBJECTIVES: This study used proton magnetic resonance spectroscopy ((1)H MRS) to evaluate the in vivo effects of extended-release divalproex sodium on the glutamatergic system in adolescents with bipolar disorder, and to identify baseline neurochemical predictors of clinical remission. METHOD: Adolescents with bipolar disorder who were experiencing a manic or mixed episode (N = 25) were treated with open-label, extended-release divalproex (serum levels 85-125 µg/mL) and underwent (1)H MRS scanning at baseline (before treatment) and on days 7 and 28. Healthy comparison subjects (n = 15) also underwent (1)H MRS scanning at the same time points. Glutamate (Glu) and glutamate+glutamine (Glx) concentrations were measured in three voxels: anterior cingulate cortex (ACC), left ventrolateral prefrontal cortex (LVLPFC), and right ventrolateral prefrontal cortex (RVLPFC), and were compared between bipolar and healthy subjects. Within the bipolar subjects, Glu and Glx concentrations at baseline and each time point were also compared between remitters and nonremitters after divalproex treatment. RESULTS: At baseline, no differences in Glu or Glx concentrations between bipolar and healthy subjects were observed. Group (HC vs. BP) by time effects revealed an interaction for Glu in the ACC, and change over time effects for Glx were noted in the ACC in patients with bipolar disorder (increase from day 0 to day 7 and then a decrease from day 7 to day 28) but not in HC. Remitters had significantly lower baseline Glx concentrations in LVLPFC, and in remitters the change in LVLPFC Glu correlated with the change in YMRS score. CONCLUSIONS: Successful treatment of mania with divalproex may be predicted by lower baseline concentrations of Glx in the LVLPFC. In addition, in remitters, the degree of symptomatic improvement is related to the change in Glu concentrations in this region, suggesting that divalproex may work via modulation of the prefrontal glutamatergic system in youth with bipolar disorder.


Assuntos
Transtorno Bipolar , Córtex Cerebral , Ácido Glutâmico/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Ácido Valproico , Adolescente , Antimaníacos/farmacologia , Antimaníacos/uso terapêutico , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Córtex Cerebral/fisiopatologia , Feminino , Humanos , Masculino , Neurotransmissores/metabolismo , Escalas de Graduação Psiquiátrica , Indução de Remissão , Resultado do Tratamento , Ácido Valproico/farmacologia , Ácido Valproico/uso terapêutico
16.
Depress Anxiety ; 29(11): 939-47, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22628125

RESUMO

BACKGROUND: Dysfunction of neural systems responsible for the processing of emotional stimuli is hypothesized to be involved in the pathophysiology of generalized anxiety disorder (GAD) in adolescents. We used standard fMRI and functional connectivity analyses to examine the functional neurocircuitry of GAD in adolescents. METHODS: Ten adolescents with GAD and 10 healthy comparison subjects underwent fMRI while performing a continuous performance task with emotional and neutral distractors. Standard event-related voxel-wise fMRI and steady-state functional connectivity analyses were performed. RESULTS: Increased activation was observed in the left medial prefrontal cortex and right ventrolateral prefrontal cortex (VLPFC) in response to emotional images compared to neutral imagines in youth with GAD. Connectivity analyses using the right VLPFC seed region suggested decreased connectivity between this region and the bilateral medial prefrontal cortex. Connectivity analyses using the right amygdala seed region revealed decreased correlation with the posterior cingulate cortex in adolescents with GAD. The left amygdala seed region demonstrated increased connectivity with the ipsilateral precuneus in youth with GAD compared to healthy subjects. CONCLUSIONS: In addition to increased activation of the medial prefrontal cortex and right VLPFC, we observed altered connectivity between the amygdala or VLPFC and regions, which subserve mentalization (e.g. posterior cingulate cortex, precuneus, and medial prefrontal cortex). This suggests that structures that regulate emotion and affect interact abnormally with key structures that are involved in mentalization, a process known to be disrupted in GAD.


Assuntos
Transtornos de Ansiedade/fisiopatologia , Encéfalo/fisiopatologia , Vias Neurais/fisiopatologia , Adolescente , Afeto , Tonsila do Cerebelo/fisiopatologia , Estudos de Casos e Controles , Criança , Emoções , Feminino , Neuroimagem Funcional , Giro do Cíngulo/fisiopatologia , Humanos , Imagem por Ressonância Magnética , Masculino , Lobo Parietal/fisiopatologia , Projetos Piloto , Córtex Pré-Frontal/fisiopatologia
17.
Psychiatry Res ; 193(2): 107-12, 2011 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-21683555

RESUMO

Several lines of evidence suggest that the neuropathophysiology of bipolar disorder is marked by structural and functional abnormalities in the caudate. We used magnetic resonance spectroscopy imaging (MRSI) to examine potential neurochemical changes in the caudate of adult bipolar patients (BP). 2D-MRSI scans including the caudate were obtained from 25 BP and 9 healthy subjects (HS). BP patients were further divided into medicated (n=14) and unmedicated (n=11) groups; the majority of medicated patients received atypical antipsychotics (AAP). Ratios of Cr/Cho, Cho/NAA and Cr/NAA in the caudate were compared between groups, controlling for age, gender and gray/white ratio. BP and HS did not significantly differ on any ratios. The Cr/Cho ratio, however, was significantly greater in medicated BP compared to HS. Conversely, the Cho/NAA ratio was non-significantly lower in medicated BP vs. HS. Medicated BP also showed significantly greater Cr/Cho and significantly smaller Cho/NAA ratios than unmedicated BP. Although we did not observe significant overall differences between BP and HS, our findings suggest the presence of reduced choline levels in the caudate of medicated BP receiving AAP. While speculative, these results suggest that AAP do not cause oxidative injury to neuronal membranes.


Assuntos
Transtorno Bipolar/patologia , Núcleo Caudado/metabolismo , Adolescente , Adulto , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Ácido Aspártico/metabolismo , Transtorno Bipolar/tratamento farmacológico , Mapeamento Encefálico , Núcleo Caudado/efeitos dos fármacos , Colina/metabolismo , Creatina/metabolismo , Feminino , Humanos , Imagem por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Adulto Jovem
18.
Proc Natl Acad Sci U S A ; 106(40): 16913-8, 2009 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-19805101

RESUMO

The delivery of nucleic acids with polycations offers tremendous potential for developing highly specific treatments for various therapeutic targets. Although materials have been developed and studied for polynucleotide transfer, the biological mechanisms and fate of the synthetic vehicle has remained elusive due to the limitations with current labeling technologies. Here, we have developed polymer beacons that allow the delivery of nucleic acids to be visualized at different biological scales. The polycations have been designed to contain repeated oligoethyleneamines, for binding and compacting nucleic acids into nanoparticles, and lanthanide (Ln) chelates [either luminescent europium (Eu(3+)) or paramagnetic gadolinium (Gd(3+))]. The chelated Lns allow the visualization of the delivery vehicle both on the nm/microm scale via microscopy and on the sub-mm scale via MRI. We demonstrate that these delivery beacons effectively bind and compact plasmid (p)DNA into nanoparticles and protect nucleic acids from nuclease damage. These delivery beacons efficiently deliver pDNA into cultured cells and do not exhibit toxicity. Micrographs of cultured cells exposed to the nanoparticle complexes formed with fluorescein-labeled pDNA and the europium-chelated polymers reveal effective intracellular imaging of the delivery process. MRI of bulk cells exposed to the complexes formulated with pDNA and the gadolinium-chelated structures show bright image contrast, allowing visualization of effective intracellular delivery on the tissue-scale. Because of their versatility, these delivery beacons posses remarkable potential for tracking and understanding nucleic acid transfer in vitro, and have promise as in vivo theranostic agents.


Assuntos
DNA/química , Luminescência , Imagem por Ressonância Magnética/métodos , Polímeros/química , DNA/genética , Európio/química , Fluoresceína-5-Isotiocianato/química , Gadolínio/química , Técnicas de Transferência de Genes , Células HeLa , Humanos , Aumento da Imagem/métodos , Elementos da Série dos Lantanídeos/química , Magnetismo , Microscopia Eletrônica de Transmissão , Estrutura Molecular , Nanopartículas/química , Nanopartículas/ultraestrutura , Tamanho da Partícula , Plasmídeos/química , Plasmídeos/genética , Poliaminas/química , Polietilenos/química , Transfecção/métodos
19.
Top Stroke Rehabil ; 15(5): 427-50, 2008 Sep-Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19008203

RESUMO

Brain-mapping techniques have proven to be vital in understanding the molecular, cellular, and functional mechanisms of recovery after stroke. This article briefly summarizes the current molecular and functional concepts of stroke recovery and addresses how various neuroimaging techniques can be used to observe these changes. The authors provide an overview of various techniques including diffusion-tensor imaging (DTI), magnetic resonance spectroscopy (MRS), ligand-based positron emission tomography (PET), single-photon emission computed tomography (SPECT), regional cerebral blood flow (rCBF) and regional metabolic rate of glucose (rCMRglc) PET and SPECT, functional magnetic resonance imaging (fMRI), near infrared spectroscopy (NIRS), electroencephalography (EEG), magnetoencephalography (MEG), and transcranial magnetic stimulation (TMS). Discussion in the context of poststroke recovery research informs about the applications and limitations of the techniques in the area of rehabilitation research. The authors also provide suggestions on using these techniques in tandem to more thoroughly address the outstanding questions in the field.


Assuntos
Mapeamento Encefálico/métodos , Recuperação de Função Fisiológica , Acidente Vascular Cerebral , Eletroencefalografia , Humanos , Imagem por Ressonância Magnética , Magnetoencefalografia , Tomografia por Emissão de Pósitrons , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia , Reabilitação do Acidente Vascular Cerebral , Tomografia Computadorizada de Emissão de Fóton Único , Estimulação Magnética Transcraniana
20.
Bioconjug Chem ; 19(8): 1505-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18620446

RESUMO

The development of novel macromolecular contrast agents that offer enhanced relaxivity profiles at high magnetic fields have the potential to greatly improve the diagnosis, understanding, and treatment of disease. To this end, we have designed a monodiperse paramagnetic beta-cyclodextrin click cluster decorated with seven paramagnetic arms. A novel alkyne-functionalized diethylenetriaminetetraacetic acid (DTTA) chelate (6) has been created and coupled to a per-azido-beta-cyclodextrin core (7) to yield the precursor macromolecule (8). After removal of the protecting groups and titrating with Gd (3+), the final paramagnetic click cluster, Gd10, was obtained. Luminescence measurements were carried out in H 2O and D 2O on an analogous structure, Eu10, and indicated that at each lanthanide has an average of 1.8 water exchange sites, which is important for enhancing relaxivity and MRI resolution. This discrete paramagnetic click cluster yields a high relaxivity profile (43.4 mM (-1) s (-1) per molecule and 6.2 mM (-1) s (-1) per Gd (3+) at 9.4 T) and enhanced contrast on a human MRI scanner as compared to a commercial agent, Magnevist (3.2 mM (-1) s (-1) at 9.4 T). Moreover, the useful inclusion properties exhibited by beta-cyclodextrin also make this an excellent host scaffold to functionalize via noncovalent assembly with receptor specific targeting moieties for biomolecular imaging.


Assuntos
Quelantes/química , Meios de Contraste/química , Magnetismo , Água/química , beta-Ciclodextrinas/química , Humanos , Imagem por Ressonância Magnética
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