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2.
J Clin Psychiatry ; 83(3)2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35377567

RESUMO

Objective: Suicidal ideation (SI) is a risk factor for completed suicide. Our previous resting state functional magnetic resonance imaging (fMRI) study found that higher amplitude of low frequency fluctuation (ALFF) in right hippocampus and thalamus was associated with SI in major depressive disorder (MDD). The present study aimed to evaluate that association in participants with bipolar disorder (BD).Methods: Thirty depressed, adult participants with a DSM-IV diagnosis of BD had resting state fMRI scans. Region-of-interest (ROI) analyses used ALFF values within areas that were previously associated with SI in MDD. Spearman rank correlation and ordinal regression analyses were performed to assess associations between ALFF values and the SI item of the Montgomery-Asberg Depression Rating Scale. Exploratory whole-brain analyses identified regions where ALFF was associated with SI.Results: Within the right hippocampus region, SI was positively associated with ALFF (Spearman R = 0.490, P = .0060). Ordinal regression analysis indicated that for every 0.1-unit increase in ALFF in that region, the odds of having higher SI were increased by 35% (odds ratio = 1.35; 95% confidence interval, 1.08-1.73; P = .012). Within the previously identified thalamus cluster, SI was associated with ALFF only at a trend level (Spearman R = 0.310, P = .069). Whole-brain analyses identified 3 clusters of positive association between SI and ALFF, 1 of which was located in the right hippocampus.Conclusions: This study found that our previous finding of positive association between SI and ALFF in the right hippocampus extended to bipolar depression. Future studies should examine the clinical utility of this association, and the role of the hippocampus in SI.Trial Registration: Data used for this secondary analysis came from studies with ClinicalTrials.gov identifiers NCT02239094 (January 2015 through September 2016) and NCT02473250 (January 2015 through December 2019).


Assuntos
Transtorno Bipolar , Transtorno Depressivo Maior , Adulto , Transtorno Bipolar/diagnóstico , Mapeamento Encefálico , Transtorno Depressivo Maior/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Ideação Suicida
3.
Int J Neuropsychopharmacol ; 25(7): 534-544, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34996114

RESUMO

BACKGROUND: The pathophysiology of bipolar disorder (BD) remains largely unknown despite it causing significant disability and suicide risk. Serotonin signaling may play a role in the pathophysiology, but direct evidence for this is lacking. Treatment of the depressed phase of the disorder is limited. Previous studies have indicated that positron emission tomography (PET) imaging of the serotonin 1A receptor (5HT1AR) may predict antidepressant response. METHODS: A total of 20 participants with BD in a current major depressive episode and 16 healthy volunteers had PET imaging with [11C]CUMI-101, employing a metabolite-corrected input function for quantification of binding potential to the 5HT1AR. Bipolar participants then received an open-labeled, 6-week clinical trial with a selective serotonin reuptake inhibitor (SSRI) in addition to their mood stabilizer. Clinical ratings were obtained at baseline and during SSRI treatment. RESULTS: Pretreatment binding potential (BPF) of [11C]CUMI-101 was associated with a number of pretreatment clinical variables within BD participants. Within the raphe nucleus, it was inversely associated with the baseline Montgomery Åsberg Rating Scale (P = .026), the Beck Depression Inventory score (P = .0023), and the Buss Durkee Hostility Index (P = .0058), a measure of lifetime aggression. A secondary analysis found [11C]CUMI-101 BPF was higher in bipolar participants compared with healthy volunteers (P = .00275). [11C]CUMI-101 BPF did not differ between SSRI responders and non-responders (P = .907) to treatment and did not predict antidepressant response (P = .580). Voxel-wise analyses confirmed the results obtained in regions of interest analyses. CONCLUSIONS: A disturbance of serotonin system function is associated with both the diagnosis of BD and its severity of depression. Pretreatment 5HT1AR binding did not predict SSRI antidepressant outcome.The study was listed on clinicaltrials.gov with identifier NCT02473250.


Assuntos
Transtorno Bipolar , Transtorno Depressivo Maior , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Transtorno Bipolar/diagnóstico por imagem , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/metabolismo , Radioisótopos de Carbono/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Humanos , Tomografia por Emissão de Pósitrons/métodos , Receptor 5-HT1A de Serotonina , Serotonina , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico
4.
Front Psychiatry ; 12: 653026, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149476

RESUMO

N-methyl-D-aspartate glutamate-receptor (NMDAR) antagonists such as ketamine have demonstrated efficacy in both major depressive disorder (MDD) and bipolar disorder depression (BP-D). We have previously reported that reduction in Glx (glutamate + glutamine) in the ventromedial prefrontal cortex/anterior cingulate cortex (vmPFC/ACC), measured by proton magnetic resonance spectroscopy (1H MRS) at 3T during a ketamine infusion, mediates the relationship of ketamine dose and blood level to improvement in depression. In the present study, we assessed the impact of D-cycloserine (DCS), an oral NMDAR antagonist combined with lurasidone in BP-D on both glutamate and Glx. Subjects with DSM-V BP-D-I/II and a Montgomery-Asberg Depression Rating Scale (MADRS) score>17, underwent up to three 1H MRS scans. During Scan 1, subjects were randomized to receive double-blind lurasidone 66 mg or placebo. During Scan 2, all subjects received single-blind DCS 950 mg + lurasidone 66 mg, followed by 4 weeks of open label phase of DCS+lurasidone and an optional Scan 3. Five subjects received lurasidone alone and three subjects received placebo for Scan 1. Six subjects received DCS+lurasidone during Scan 2. There was no significant baseline or between treatment-group differences in acute depression improvement or glutamate response. In Scan 2, after a dose of DCS+lurasidone, peak change in glutamate correlated negatively with improvement from baseline MADRS (r = -0.83, p = 0.04). There were no unexpected adverse events. These preliminary pilot results require replication but provide further support for a link between antidepressant effect and a decrease in glutamate by the NMDAR antagonist class of antidepressants.

5.
Neurosci Res ; 162: 63-70, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31931027

RESUMO

Previous studies based on an assumption of connectivity stationarity reported disconnections in mirror neuron system (MNS) and mentalizing networks of schizophrenic brains with social cognitive disruptions. However, recent studies demonstrated that functional brain connections are dynamic, and static connectivity metrics fail to capture time-varying properties of functional connections. The present study used a dynamic functional connectivity (dFC) method to test whether alterations of functional connectivity in the two networks are time-varying in adolescent-onset schizophrenia (AOS) patients. We collected resting-state fMRI data from 28 patients with AOS and 22 matched healthy controls. Static functional connectivity and dFC were used to explore the connectivity difference in the MNS and mentalizing networks between the two groups, respectively. Then a Pearson's correlation analysis between the connectivity showing intergroup differences and clinical scores was conducted in the AOS group. Compared with static functional connectivity analyses, dFC revealed state-specific connectivity decreases within the MNS network in the AOS group. Additionally, the dFC between the left middle temporal gyrus and left V5 was negatively correlated with the item2 of PANSS negative scores across all the AOS patients. Our findings suggest that social dysfunctions in AOS patients may be associated with the altered integrity and interaction of the MNS and mentalizing networks, and the functional impairments in the MNS are dynamic over time.


Assuntos
Mentalização , Neurônios-Espelho , Preparações Farmacêuticas , Esquizofrenia , Adolescente , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética , Vias Neurais/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem
6.
Bipolar Disord ; 22(3): 296-302, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31604361

RESUMO

OBJECTIVE: To compare white matter integrity (WMI) in bipolar disorder (BD) relative to healthy volunteers (HVs) and major depressive disorder (MDD). To determine the relationship of bipolar-specific differences in WMI to cerebral perfusion, body mass index (BMI), and blood pressure as indices of cardiovascular function. METHODS: Thirty-two participants with BD, 44 with MDD, and 41 HV were recruited. All BD and MDD participants were in a major depressive episode, and all but 12 BD participants were medication-free. 64-direction diffusion tensor imaging (DTI) and arterial spin labeling (ASL) sequences were obtained. Tract-based spatial statistics (TBSS) on four DTI indices were employed to distinguish patterns of DTI in BD relative to HV and MDD groups. BMI, blood pressure, and medical histories were also obtained for the BD participants. RESULTS: A cluster of lower axial diffusivity (AD) was found in BD participants in comparison to the HVs in the left posterior thalamic radiation, superior longitudinal fasciculus, inferior longitudinal fasciculus, fronto-occipital fasciculus, and internal capsule. Mean AD in the significant cluster was not associated with cerebral blood flow (CBF) in the region as measured by ASL, and was not associated with BMI or blood pressure. A cluster of lower AD was also found in the BD group when compared to MDD that had spatial overlap with the HV comparison. CONCLUSIONS: The results indicate a deficit of AD in BD when compared to MDD and HV groups. No association between AD values and either cerebral perfusion, BMI, or blood pressure was found in BD.


Assuntos
Transtorno Bipolar/patologia , Índice de Massa Corporal , Circulação Cerebrovascular/fisiologia , Transtorno Depressivo Maior/patologia , Substância Branca/patologia , Adulto , Transtorno Bipolar/diagnóstico por imagem , Transtorno Depressivo Maior/diagnóstico por imagem , Imagem de Tensor de Difusão , Feminino , Humanos , Cápsula Interna/diagnóstico por imagem , Cápsula Interna/patologia , Masculino , Pessoa de Meia-Idade , Substância Branca/diagnóstico por imagem
7.
Depress Anxiety ; 36(8): 766-779, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31111623

RESUMO

BACKGROUND: Brain mitochondrial dysfunction is implicated in the pathophysiology of mood disorders. Brain cytochrome-c-oxidase (COX) activity is associated with the mitochondrial function. Near-infrared spectroscopy (NIRS) noninvasively measures oxidized COX (oxCOX) and tissue oxygenation index (TOI) reflecting cerebral blood flow and oxygenation. METHODS: oxCOX and TOI were assessed in prefrontal cortex (Fp1/2, Brodmann area 10) in patients in a major depressive episode (N = 13) with major depressive disorder (MDD; N = 7) and bipolar disorder (BD; N = 6) compared with the controls (N = 10). One patient with MDD and all the patients with BD were taking medications. Computational modeling estimated oxCOX and TOI related indices of mitochondrial function and cerebral blood flow, respectively. RESULTS: oxCOX was lower in patients than controls (p = .014) correlating inversely with depression severity (r = -.72; p = .006), driven primarily by lower oxCOX in BD compared with the controls. Computationally modeled mitochondrial parameters of the electron transport chain, such as the nicotinamide adenine dinucleotide ratio (NAD+ /NADH; p = .001) and the proton leak rate across the inner mitochondrial membrane (klk2 ; p = .008), were also lower in patients and correlated inversely with depression severity. No such effects were found for TOI. CONCLUSIONS: In this pilot study, oxCOX and related mitochondrial parameters assessed by NIRS indicate an abnormal cerebral metabolic state in mood disorders proportional to depression severity, potentially providing a biomarker of antidepressant effect. Because the effect was driven by the medicated BD group, findings need to be evaluated in a larger, medication-free population.


Assuntos
Encéfalo/metabolismo , Encéfalo/fisiopatologia , Transtorno Depressivo Maior/metabolismo , Transtorno Depressivo Maior/fisiopatologia , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Mitocôndrias/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Mapeamento Encefálico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/fisiologia , Projetos Piloto , Espectroscopia de Luz Próxima ao Infravermelho , Adulto Jovem
8.
Depress Anxiety ; 36(5): 433-441, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30900329

RESUMO

BACKGROUND: Identifying brain activity patterns that are associated with suicidal ideation (SI) may help to elucidate its pathogenesis and etiology. Suicide poses a significant public health problem, and SI is a risk factor for suicidal behavior. METHODS: Forty-one unmedicated adult participants in a major depressive episode (MDE), 26 with SI on the Beck Scale for Suicidal Ideation and 15 without SI, underwent resting-state functional magnetic resonance imaging scanning. Twenty-one healthy volunteers (HVs) were scanned for secondary analyses. Whole brain analysis of both amplitude of low-frequency fluctuations (ALFFs) and fractional ALFF was performed in MDE subjects to identify regions where activity was associated with SI. RESULTS: Subjects with SI had greater ALFF than those without SI in two clusters: one in the right hippocampus and one in the thalamus and caudate, bilaterally. Multi-voxel pattern analysis distinguished between those with and without SI. Post hoc analysis of the mean ALFF in the hippocampus cluster found it to be associated with a delayed recall on the Buschke memory task. Mean ALFF from the significant clusters was not associated with depression severity and did not differ between MDE and HV groups. DISCUSSION: These results indicate that SI is associated with altered resting-state brain activity. The pattern of elevated activity in the hippocampus may be related to how memories are processed.


Assuntos
Mapeamento Encefálico/métodos , Núcleo Caudado/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Hipocampo/fisiopatologia , Ideação Suicida , Tálamo/fisiopatologia , Adulto , Núcleo Caudado/diagnóstico por imagem , Transtorno Depressivo Maior/diagnóstico por imagem , Feminino , Hipocampo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Tálamo/diagnóstico por imagem
9.
Brain Stimul ; 11(3): 575-581, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29454551

RESUMO

BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) is an effective treatment for medication-refractory major depression, yet the mechanisms of action for this intervention are poorly understood. Here we investigate cerebral cortex thickness as a possible biomarker of rTMS treatment response. METHODS: Longitudinal change in cortical thickness is evaluated relative to clinical outcomes across 48 participants in 2 cohorts undergoing left dorsolateral prefrontal cortex rTMS as a treatment for depression. RESULTS: Our results reveal changes in thickness in a region of the left rostral anterior cingulate cortex that correlate with clinical response, with this region becoming thicker in patients who respond favorably to rTMS and thinner in patients with a less favorable response. Moreover, the baseline cortical thickness in this region correlates with rTMS treatment response - those patients with thinner cortex before treatment tended to have the most clinical improvement. CONCLUSIONS: This study is the first analysis of longitudinal cortical thickness change with rTMS as a treatment for depression with similar results across two cohorts. These results support further investigation into the use of structural MRI as a possible biomarker of rTMS treatment response.


Assuntos
Transtorno Depressivo Maior/terapia , Transtorno Depressivo Resistente a Tratamento/terapia , Giro do Cíngulo/anatomia & histologia , Córtex Pré-Frontal/fisiologia , Estimulação Magnética Transcraniana , Feminino , Humanos , Hipertrofia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Resultado do Tratamento
10.
J Affect Disord ; 227: 498-505, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29156364

RESUMO

BACKGROUND: Bipolar Disorder (BD) cannot be reliably distinguished from Major Depressive Disorder (MDD) until the first manic or hypomanic episode. Consequently, many patients with BD are treated with antidepressants without mood stabilizers, a strategy that is often ineffective and carries a risk of inducing a manic episode. We previously reported reduced cortical thickness in right precuneus, right caudal middle-frontal cortex and left inferior parietal cortex in BD compared with MDD. METHODS: This study extends our previous work by performing individual level classification of BD or MDD in an expanded, currently unmedicated, cohort using gray matter volume (GMV) based on Magnetic Resonance Imaging and a Support Vector Machine. All patients were in a Major Depressive Episode and a leave-two-out analysis was performed. RESULTS: Nineteen out of 26 BD subjects and 20 out of 26 MDD subjects were correctly identified, for a combined accuracy of 75%. The three brain regions contributing to the classification were higher GMV in bilateral supramarginal gyrus and occipital cortex indicating MDD, and higher GMV in right dorsolateral prefrontal cortex indicating BD. LIMITATIONS: This analysis included scans performed with two different headcoils and scan sequences, which limited the interpretability of results in an independent cohort analysis. CONCLUSIONS: Our results add to previously published data which suggest that regional gray matter volume should be investigated further as a clinical diagnostic tool to predict BD before the appearance of a manic or hypomanic episode.


Assuntos
Transtorno Bipolar/patologia , Córtex Cerebral/patologia , Transtorno Depressivo Maior/patologia , Substância Cinzenta/patologia , Adulto , Transtorno Bipolar/diagnóstico por imagem , Encéfalo/patologia , Córtex Cerebral/diagnóstico por imagem , Transtorno Ciclotímico/patologia , Transtorno Depressivo Maior/diagnóstico por imagem , Feminino , Lobo Frontal/patologia , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Lobo Occipital/patologia , Lobo Parietal/patologia
11.
J Alzheimers Dis ; 60(3): 939-947, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28984586

RESUMO

This project compares three neuroimaging biomarkers to predict progression to dementia in subjects with mild cognitive impairment (MCI). Eighty-eight subjects with MCI and 40 healthy controls (HCs) were recruited. Subjects had a 3T magnetic resonance imaging (MRI) scan, and two positron emission tomography (PET) scans, one with Pittsburgh compound B ([11C]PIB) and one with fluorodeoxyglucose ([18F]FDG). MCI subjects were followed for up to 4 y and progression to dementia was assessed on an annual basis. MCI subjects had higher [11C]PIB binding potential (BPND) than HCs in multiple brain regions, and lower hippocampus volumes. [11C]PIB BPND, [18F]FDG standard uptake value ratio (SUVR), and hippocampus volume were associated with time to progression to dementia using a Cox proportional hazards model. [18F]FDG SUVR demonstrated the most statistically significant association with progression, followed by [11C]PIB BPND and then hippocampus volume. [11C]PIB BPND and [18F]FDG SUVR were independently predictive, suggesting that combining these measures is useful to increase accuracy in the prediction of progression to dementia. Hippocampus volume also had independent predictive properties to [11C]PIB BPND, but did not add predictive power when combined with the [18F]FDG SUVR data. This work suggests that PET imaging with both [11C]PIB and [18F]FDG may help to determine which MCI subjects are likely to progress to AD, possibly directing future treatment options.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo , Demência/diagnóstico por imagem , Demência/metabolismo , Idoso , Idoso de 80 Anos ou mais , Compostos de Anilina , Apolipoproteínas E/genética , Benzotiazóis , Encéfalo/patologia , Disfunção Cognitiva/genética , Disfunção Cognitiva/patologia , Demência/genética , Demência/patologia , Progressão da Doença , Feminino , Fluordesoxiglucose F18 , Humanos , Estimativa de Kaplan-Meier , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Tomografia por Emissão de Pósitrons , Prognóstico , Modelos de Riscos Proporcionais , Compostos Radiofarmacêuticos , Tiazóis
12.
Bipolar Disord ; 19(6): 444-449, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28796415

RESUMO

OBJECTIVES: Patients with bipolar disorder spend the most time in the depressed phase, and that phase is associated with the most morbidity and mortality. Treatment of bipolar depression lacks a test to determine who will respond to treatment. White matter disruptions have been found in bipolar disorder. Previous reports suggest that white matter disruptions may be associated with resistance to antidepressant medication, but this has never been investigated in a prospective study using a Food and Drug Administration (FDA)-approved medication. METHODS: Eighteen subjects with bipolar disorder who were in a major depressive episode and off all medications were recruited. Magnetic resonance imaging was acquired using a 64-direction diffusion tensor imaging sequence on a 3T scanner. Subjects were treated with 8 weeks of open-label lurasidone. The Montgomrey-Asberg Depression Rating Scale (MADRS) was completed weekly. Tract-Based Spatial Statistics were utilized to perform a regression analysis of fractional anisotropy (FA) data with treatment outcome as assessed by percent change in MADRS as a regressor while controlling for age and sex, using a threshold of P (threshold-free cluster enhancement-corrected) <.05. RESULTS: FA was positively correlated with antidepressant treatment response in multiple regions of the mean FA skeleton bilaterally, including tracts in the frontal and parietal lobes. CONCLUSIONS: Greater disruptions in the white matter tracts in bipolar disorder were associated with poorer antidepressant response to lurasidone. The disruptions may potentially indicate treatment with a different antidepressant medication class. These results are limited by the open-label study design, sample size and lack of a healthy control group.


Assuntos
Transtorno Bipolar , Transtorno Depressivo Resistente a Tratamento/diagnóstico , Cloridrato de Lurasidona/administração & dosagem , Substância Branca , Adulto , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/tratamento farmacológico , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Estudos Prospectivos , Escalas de Graduação Psiquiátrica , Reprodutibilidade dos Testes , Antagonistas do Receptor 5-HT2 de Serotonina/administração & dosagem , Estatística como Assunto , Substância Branca/diagnóstico por imagem , Substância Branca/efeitos dos fármacos , Substância Branca/patologia
13.
Brain Stimul ; 9(4): 577-83, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27017072

RESUMO

BACKGROUND: Repetitive transcranial magnetic stimulation (TMS) is an FDA-approved antidepressant treatment but little is known of its mechanism of action. Specifically, downstream effects of TMS remain to be elucidated. OBJECTIVE/HYPOTHESIS: This study aims to identify brain structural changes from TMS treatment of a treatment resistant depressive episode through an exploratory analysis. METHODS: Twenty-seven subjects in a DSM-IV current major depressive episode and on a stable medication regimen had a 3T magnetic resonance T1 structural scan before and after five weeks of standard TMS treatment to the left dorsolateral prefrontal cortex. Twenty-seven healthy volunteer (HVs) subjects had the same brain MRI acquisition. Voxel-based morphometry was performed using high dimensional non-linear diffusomorphic anatomical registration (DARTEL). RESULTS: Six clusters of gray matter volume (GMV) that were lower in pre-treatment MRIs of depressed subjects than in HVs. GMV in four of these regions increased in MDD after TMS treatment by 3.5-11.2%. The four brain regions that changed with treatment were centered in the left anterior cingulate cortex, the left insula, the left superior temporal gyrus and the right angular gyrus. Increases in the anterior cingulate GMV with TMS correlated with improvement in depression severity. CONCLUSIONS: To our knowledge, this is the first study of brain structural changes during TMS treatment of depression. The affected brain areas are involved in cognitive appraisal, decision-making and subjective experience of emotion. These effects may have potential relevance for the antidepressant action of TMS.


Assuntos
Córtex Cerebral/patologia , Transtorno Depressivo Maior/terapia , Transtorno Depressivo Resistente a Tratamento/terapia , Estimulação Magnética Transcraniana/métodos , Adulto , Córtex Cerebral/diagnóstico por imagem , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Resistente a Tratamento/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
14.
Neuroimage ; 94: 33-39, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24607934

RESUMO

Brain Derived Neurotrophic Factor (BDNF) regulates brain synaptic plasticity. BDNF affects serotonin signaling, increases serotonin levels in brain tissue and prevents degeneration of serotonin neurons. These effects have hardly been studied in human brain. We examined the relationship of the functional val66met polymorphism of the BDNF gene to serotonin 1A (5-HT(1A)) receptor binding in vivo. 50 healthy volunteers (HV) and 50 acutely depressed, unmedicated patients with major depressive disorder (MDD) underwent PET scanning with the 5-HT(1A) receptor ligand, [(11)C]WAY-100635 and a metabolite corrected arterial input function. A linear mixed effects model compared 5-HT(1A) receptor binding potential (BP(F), proportional to the number of available receptors) in 13 brain regions of interest between met allele carriers (met/met and val/met) and noncarriers (val/val) using sex and C-1019G genotype of the 5-HT(1A) receptor promoter functional polymorphism as covariates. There was an interaction between diagnosis and allele (F=4.23, df=1, 94, p=0.042), such that met allele carriers had 17.4% lower BP(F) than non-met carriers in the HV group (t=2.6, df=96, p=0.010), but not in the MDD group (t=-0.4, df=96, p=0.58). These data are consistent with a model where the met allele of the val66met polymorphism causes less proliferation of serotonin synapses, and consequently fewer 5-HT(1A) receptors. In MDD, however, the effect of the val66met polymorphism is not detectable, possibly due to a ceiling effect of over-expression of 5-HT(1A) receptors in mood disorders.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Encéfalo/fisiopatologia , Depressão/genética , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/metabolismo , Polimorfismo Genético/genética , Receptor 5-HT1A de Serotonina/metabolismo , Adolescente , Adulto , Idoso , Alelos , Depressão/metabolismo , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença/genética , Variação Genética/genética , Humanos , Masculino , Pessoa de Meia-Idade , Piperazinas/farmacocinética , Polimorfismo de Nucleotídeo Único/genética , Tomografia por Emissão de Pósitrons/métodos , Ligação Proteica , Piridinas/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Receptor 5-HT1A de Serotonina/genética , Estatística como Assunto , Distribuição Tecidual , Adulto Jovem
15.
Bipolar Disord ; 16(4): 378-88, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24428430

RESUMO

OBJECTIVES: Bipolar disorder (BD) is a psychiatric disorder with high morbidity and mortality that cannot be distinguished from major depressive disorder (MDD) until the first manic episode. A biomarker able to differentiate BD and MDD could help clinicians avoid risks of treating BD with antidepressants without mood stabilizers. METHODS: Cortical thickness differences were assessed using magnetic resonance imaging in BD depressed patients (n = 18), MDD depressed patients (n = 56), and healthy volunteers (HVs) (n = 54). A general linear model identified clusters of cortical thickness difference between diagnostic groups. RESULTS: Compared to the HV group, the BD group had decreased cortical thickness in six regions, after controlling for age and sex, located within the frontal and parietal lobes, and the posterior cingulate cortex. Mean cortical thickness changes in clusters ranged from 7.6 to 9.6% (cluster-wise p-values from 1.0 e-4 to 0.037). When compared to MDD, three clusters of lower cortical thickness in BD were identified that overlapped with clusters that differentiated the BD and HV groups. Mean cortical thickness changes in the clusters ranged from 7.5 to 8.2% (cluster-wise p-values from 1.0 e-4 to 0.023). The difference in cortical thickness was more pronounced when the subgroup of subjects with bipolar I disorder (BD-I) was compared to the MDD group. CONCLUSIONS: Cortical thickness patterns were distinct between BD and MDD. These results are a step toward developing an imaging test to differentiate the two disorders.


Assuntos
Transtorno Bipolar/patologia , Córtex Cerebral/patologia , Transtorno Depressivo Maior/patologia , Adulto , Análise de Variância , Encéfalo/patologia , Feminino , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica
16.
Synapse ; 67(11): 773-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23720414

RESUMO

Bipolar disorder is a major cause of disability and a high risk for suicide. The pathophysiology of the disorder remains largely unknown. Medication choice for bipolar depression patients involves trial and error. Our group reported previously that brain serotonin 1A (5-HT(1A)) receptor binding measured by positron emission tomography (PET) is higher in bipolar depression. We now investigated whether pretreatment 5-HT(1A) levels correlates with antidepressant medication outcome. Forty-one medication-free DSM-IV diagnosed, bipolar patients in a major depressive episode had brain PET scans performed using [(11)C]WAY-100635 and a metabolite corrected arterial input function. The patients then received naturalistic psychopharmacologic treatment as outpatients and a follow up Hamilton Depression Rating Scale (HDRS) after 3 months of treatment. Patients with 24 item HDRS scores less than 10 were considered to have remitted. A linear mixed effects model was used to compare BP(F) (binding potential, proportional to the total number of available receptors) in 13 brain regions of interest between remitters and nonremitters. Thirty-four patients completed 3 months of treatment and ratings; 9 had remitted. Remitters and nonremitters did not differ in age, sex, or recent medication history with serotonergic medications. Remitters had higher [(11)C]WAY-100635 BP(F) across all brain regions compared with nonremitters (P = 0.02). Higher pretreatment brain 5-HT(1A) receptor binding was associated with remission after 3 months of pharmacological treatment in bipolar depression. Prospective treatment studies are warranted to determine whether this test predicts outcome of specific types of treatment.


Assuntos
Transtorno Bipolar/tratamento farmacológico , Transtorno Depressivo/tratamento farmacológico , Tomografia por Emissão de Pósitrons , Receptor 5-HT1A de Serotonina/metabolismo , Adulto , Antidepressivos/uso terapêutico , Transtorno Bipolar/diagnóstico por imagem , Transtorno Bipolar/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Transtorno Depressivo/diagnóstico por imagem , Transtorno Depressivo/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Piperazinas/farmacologia , Piridinas/farmacologia , Compostos Radiofarmacêuticos/farmacologia , Indução de Remissão , Serotonina/metabolismo , Agonistas do Receptor 5-HT1 de Serotonina/farmacologia , Resultado do Tratamento
17.
Genome Biol Evol ; 2: 284-92, 2010 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-20624733

RESUMO

The study of gene expression evolution in vertebrates has hitherto focused on the analysis of transcriptomes in tissues of different species. However, because a tissue is made up of different cell types, and cell types differ with respect to their transcriptomes, the analysis of tissues offers a composite picture of transcriptome evolution. The isolation of individual cells from tissue sections opens up the opportunity to study gene expression evolution at the cell type level. We have stained neurons and endothelial cells in human brains by antibodies against cell type-specific marker proteins, isolated the cells using laser capture microdissection, and identified genes preferentially expressed in the two cell types. We analyze these two classes of genes with respect to their expression in 62 different human tissues, with respect to their expression in 44 human "postmortem" brains from different developmental stages and with respect to between-species brain expression differences. We find that genes preferentially expressed in neurons differ less across tissues and developmental stages than genes preferentially expressed in endothelial cells. We also observe less expression differences within primate species for neuronal transcriptomes. In stark contrast, we see more gene expression differences between humans, chimpanzees, and rhesus macaques relative to within-species differences in genes expressed preferentially in neurons than in genes expressed in endothelial cells. This suggests that neuronal and endothelial transcriptomes evolve at different rates within brain tissue.


Assuntos
Encéfalo/metabolismo , Evolução Molecular , Primatas/genética , Animais , Encéfalo/citologia , Células Endoteliais/metabolismo , Perfilação da Expressão Gênica , Humanos , Macaca mulatta/genética , Neurônios/metabolismo , Pan troglodytes/genética , Especificidade da Espécie , Distribuição Tecidual
18.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-671347

RESUMO

Objective To summarize the experience in laparoscopic resection of metastic liver cancer. Methods The clinical data of the patients receiving laparoscopic resection of metastic liver cancer performed in Brisbane hospital from 1999 to 2006 were retrospectively analyzed. Results A total of 28 patients received the laparoscopic resection of metastic liver cancer. Procedures included left lateral segmentectomy in 13 patients, right hemihepatectomy in 9 and segmental or subsegmental resection in 6. Survival rate and disease free survival rate in 12 patients with colorectal metastasis being followed up for 2 years were 75% and 67%. Conclusion Laparoscopic liver resection is safe and feasible in strictly selected patients with malignancy in an appropriate stage. The surgeons should have rich experience of open liver resection and advanced laparoscopic technique.

19.
PLoS One ; 3(12): e3964, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19088852

RESUMO

BACKGROUND: Previous studies of brain and peripheral tissues in schizophrenia patients have indicated impaired energy supply to the brain. A number of studies have also demonstrated dysfunction of the microvasculature in schizophrenia patients. Together these findings are consistent with a hypothesis of blood-brain barrier dysfunction in schizophrenia. In this study, we have investigated the cerebral vascular endothelium of schizophrenia patients at the level of transcriptomics. METHODOLOGY/PRINCIPAL FINDINGS: We used laser capture microdissection to isolate both microvascular endothelial cells and neurons from post mortem brain tissue from schizophrenia patients and healthy controls. RNA was isolated from these cell populations, amplified, and analysed using two independent microarray platforms, Affymetrix HG133plus2.0 GeneChips and CodeLink Whole Human Genome arrays. In the first instance, we used the dataset to compare the neuronal and endothelial data, in order to demonstrate that the predicted differences between cell types could be detected using this methodology. We then compared neuronal and endothelial data separately between schizophrenic subjects and controls. Analysis of the endothelial samples showed differences in gene expression between schizophrenics and controls which were reproducible in a second microarray platform. Functional profiling revealed that these changes were primarily found in genes relating to inflammatory processes. CONCLUSIONS/SIGNIFICANCE: This study provides preliminary evidence of molecular alterations of the cerebral microvasculature in schizophrenia patients, suggestive of a hypo-inflammatory state in this tissue type. Further investigation of the blood-brain barrier in schizophrenia is warranted.


Assuntos
Encéfalo/irrigação sanguínea , Terapia a Laser/métodos , Microdissecção/métodos , Microvasos/cirurgia , Esquizofrenia/cirurgia , Adulto , Algoritmos , Autopsia , Encéfalo/metabolismo , Encéfalo/patologia , Estudos de Casos e Controles , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Esquizofrenia/genética , Esquizofrenia/patologia , Adulto Jovem
20.
J Mol Neurosci ; 35(2): 225-34, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18437585

RESUMO

Valproate (Depakote) remains an effective medication for the prevention and treatment of seizures in epilepsy and of mood symptoms in bipolar disorder. Both of these disorders are severe and debilitating, and both warrant further medication options as well as a better understanding of the side effects associated with their current treatments. Although a number of molecular and cellular processes have been found to be altered by valproate, the medication's therapeutic mechanism has not been fully elucidated. In this paper, peroxisome proliferator-activated receptor (PPAR) signaling was examined to determine valproate's effects on this transcriptional regulatory system in neuronal tissue. PPAR signaling has been found to affect a number of biochemical processes, including lipid metabolism, cellular differentiation, insulin sensitivity, and cell survival. When primary neuronal cultures were treated with valproate, a significant decrease in PPARgamma signaling was observed. This effect was demonstrated through a change in nuclear quantities of PPARgamma receptor and decreased DNA binding of the receptor. Valproate also caused gene expression changes and a change to the peroxisome biochemistry consistent with a decrease of PPARgamma signaling. These biochemical changes may have functional consequences for either valproate's therapeutic mechanism or for its neurological side effects and merit further investigation.


Assuntos
Antimaníacos/farmacologia , Neurônios/efeitos dos fármacos , PPAR gama/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ácido Valproico/farmacologia , Acil-CoA Oxidase/genética , Acil-CoA Oxidase/metabolismo , Animais , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/metabolismo , Catalase/genética , Catalase/metabolismo , Epilepsia/tratamento farmacológico , Epilepsia/metabolismo , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/fisiologia , Masculino , Neurônios/enzimologia , PPAR gama/genética , Ratos , Ratos Endogâmicos WKY , Transdução de Sinais/fisiologia
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