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Objective: The aim of the study was to investigate the clinical, neuropsychological, and regional cerebral blood flow (rCBF) perfusion changes in patients with neuropsychiatric symptoms caused by nitrous oxide (N2O) abuse. Methods: A total of 16 patients with neuropsychiatric symptoms caused by nitrous oxide abuse were recruited for this study. The study was carried out in the withdrawal phase of N2O abuse. A 925-1110 MBq 99mTc-ECD was administered intravenously. SPECT/CT images were collected with a low-energy and high-resolution collimator. The region uptake statistics of different brain regions of interest between patients with N2O abuse and normal people of the databases for younger subjects from the Scenium DB Comparison software were calculated automatically. Results: The clinical manifestations of the 16 patients with neuropsychiatric symptoms were mood lability, anxiety, hallucination, delusion, agitation, confusion, and other psychiatric symptoms. In addition, 15 of the patients also complained of memory decline; 14 patients manifested numbness or paresthesia; 14 patients developed limb weakness, and their motor impairments were more severe in the lower limbs than in the upper limbs; and eight patients had urinary and defecation disturbances. In the neuropsychological examination, the BPRS score was 54.69 ± 11.48, the HAMD score was 30.00 ± 11.06, the HAMA score was 18.06 ± 5.77, the MMSE score was 28.06 ± 2.29, and the MoCA score was 25.06 ± 3.40. SPECT showed hypoperfusion in the frontal and temporal lobes, which is consistent with the clinical findings. Conclusion: This was the first study to demonstrate the obvious effect of N2O abuse on CBF in patients with neuropsychiatric symptoms. CBF perfusion imaging is helpful to detect the changes in the local brain functional activity in patients with N2O abuse.
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Neuroimaging studies have revealed that insomnia is characterized by aberrant neuronal connectivity in specific brain regions, but the topological disruptions in the white matter (WM) structural connectivity networks remain largely unknown in insomnia. The current study uses diffusion tensor imaging (DTI) tractography to construct the WM structural networks and graph theory analysis to detect alterations of the brain structural networks. The study participants comprised 30 healthy subjects with insomnia symptoms (IS) and 62 healthy subjects without IS. Both the two groups showed small-world properties regarding their WM structural connectivity networks. By contrast, increased local efficiency and decreased global efficiency were identified in the IS group, indicating an insomnia-related shift in topology away from regular networks. In addition, the IS group exhibited disrupted nodal topological characteristics in regions involving the fronto-limbic and the default-mode systems. To our knowledge, this is the first study to explore the topological organization of WM structural network connectivity in insomnia. More importantly, the dysfunctions of large-scale brain systems including the fronto-limbic pathways, salience network and default-mode network in insomnia were identified, which provides new insights into the insomnia connectome. Topology-based brain network analysis thus could be a potential biomarker for IS.
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Insomnia is one of the most common health complaints, with a high prevalence of 30~50% in the general population. In particular, neuroimaging research has revealed that widespread dysfunctions in brain regions involved in hyperarousal are strongly correlated with insomnia. However, whether the topology of the intrinsic connectivity is aberrant in insomnia remains largely unknown. In this study, resting-state functional magnetic resonance imaging (rsfMRI) in conjunction with graph theoretical analysis, was used to construct functional connectivity matrices and to extract the attribute features of the small-world networks in insomnia. We examined the alterations in global and local small-world network properties of the distributed brain regions that are predominantly implicated in the frontostriatal network between 30 healthy subjects with insomnia symptoms (IS) and 62 healthy subjects without insomnia symptoms (NIS). Correlations between the small-world properties and clinical measurements were also generated to identify the differences between the two groups. Both the IS group and the NIS group exhibited a small-worldness topology. Meanwhile, the global topological properties didn't show significant difference between the two groups. By contrast, participants in the IS group showed decreased regional degree and efficiency in the left inferior frontal gyrus (IFG) compared with subjects in the NIS group. More specifically, significantly decreased nodal efficiency in the IFG was found to be negatively associated with insomnia scores, whereas the abnormal changes in nodal betweenness centrality of the right putamen were positively correlated with insomnia scores. Our findings suggested that the aberrant topology of the salience network and frontostriatal connectivity is linked to insomnia, which can serve as an important biomarker for insomnia.
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Poor sleep and insomnia have been recognized to be strongly correlated with the development of depression. The exploration of the basic mechanism of sleep disturbance could provide the basis for improved understanding and treatment of insomnia and prevention of depression. In this study, 31 subjects with insomnia symptoms as measured by the Hamilton Rating Scale for Depression (HAMD-17) and 71 age- and gender-matched subjects without insomnia symptoms were recruited to participate in a clinical trial. Using resting-state functional magnetic resonance imaging (rs-fMRI), we examined the alterations in spontaneous brain activity between the two groups. Correlations between the fractional amplitude of low frequency fluctuations (fALFF) and clinical measurements (e.g., insomnia severity and Hamilton Depression Rating Scale [HAMD] scores) were also tested in all subjects. Compared to healthy participants without insomnia symptoms, participants with insomnia symptoms showed a decreased fALFF in the left ventral anterior insula, bilateral posterior insula, left thalamus, and pons but an increased fALFF in the bilateral middle occipital gyrus and right precentral gyrus. More specifically, a significant, negative correlation of fALFF in the left thalamus with early morning awakening scores and HAMD scores in the overall sample was identified. These results suggest that insomnia symptoms are associated with altered spontaneous activity in the brain regions of several important functional networks, including the insular cortex of the salience and the thalamus of the hyperarousal network. The altered fALFF in the left thalamus supports the "hyperarousal theory" of insomnia symptoms, which could serve as a biomarker for insomnia.
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Córtex Cerebral/fisiopatologia , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Tálamo/fisiopatologia , Adulto , Encéfalo/fisiopatologia , Mapeamento Encefálico , Transtorno Depressivo/fisiopatologia , Feminino , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/fisiopatologia , Escalas de Graduação PsiquiátricaRESUMO
OBJECTIVE: This study aimed to investigate the association of galanin (GAL) gene and the development of depression in the Chinese Han population. METHODS: A total of 700 patients with depression who met the diagnostic criteria of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) and 673 healthy controls were used in this study. Ligase detection reactions were performed on 10 selected single nucleotide polymorphism (SNP) sites in the GAL gene. A series of statistical methods were carried out to investigate the correlation between the GAL gene SNP and the patient susceptibility to depression. RESULTS: The SNPs of rs694066 in the GAL gene showed a positive correlation with MDD. Compared with the healthy controls, lower frequency of G/G genotype and higher frequency of A/G genotype were observed in rs694066 in MDD patients, a lower frequency of G-allele and higher frequency of A-allele were observed in rs694066. These correlations were more pronounced in the 376 female patients and 360 female control subjects than in the 324 male patients and 313 healthy male subjects. CONCLUSIONS: This study investigated the relationship between the GAL gene SNP and the susceptibility to depression in the Chinese Han population. The findings clearly indicate that the GAL gene polymorphism is closely correlated to the incidence of depression in the Chinese Han female patients.
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Transtorno Depressivo Maior/genética , Galanina/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Povo Asiático , Estudos de Casos e Controles , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/etnologia , Feminino , Expressão Gênica , Frequência do Gene , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores SexuaisRESUMO
BACKGROUND: Major depressive disorder (MDD) is a highly heritable psychiatric disease, and the existing literature is not robust enough to allow us to evaluate whether MDD-associated biomarkers are state-independent heritable endophenotypes or state markers related to depression per se. METHODS: Twenty two patients diagnosed with MDD, 22 siblings, as well as 26 gender-, age-, and education-matched healthy subjects, participated in the resting-state functional magnetic resonance imaging (fMRI) analysis. We compared the differences in the fractional amplitude of low-frequency fluctuation (fALFF) among the three groups and investigated the correlation between clinical measurements and fALFF in the regions displaying significant group differences. RESULTS: Both the MDD and siblings groups showed an increased fALFF in the left middle frontal gyrus (l-MFG, Brodmann Area, BA 10) compared to the healthy controls. The MDD groups demonstrated an increased fALFF in the right dorsal medial frontal gyrus (r-DMFG, BA 9) and a decreased fALFF in the bilateral lingual gyrus relative to siblings and healthy controls. LIMITATIONS: Medication effects, an inability to control subjects' thoughts during imaging. CONCLUSIONS: Our results suggest that the dysfunction in the l-MFG may represent an imaging endophenotype which may indicate a risk for MDD. The r-DMFG may play a critical role in depressive symptomatology and may reveal therapeutic target for MDD.
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Córtex Cerebral/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Imageamento por Ressonância Magnética , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , IrmãosRESUMO
OBJECTIVE: This study aimed to investigate the single nucleotide polymorphisms (SNPs) of neuropeptide Y (NPY) and major depressive disorder (MDD) in Chinese Han population. DESIGN: Prospective and randomized studies were carried out. PATIENTS: A total of 700 patients (324 male and 376 female; mean ageâ=â40±14.9 years) with depression who met the diagnostic criteria of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) and 673 healthy controls (313 male and 360 female; mean ageâ=â41.9±17.2 years) were used to investigate the relationship between SNPs of NPY and the pathogenesis of MDD. A total of 417 patients (195 male and 202 female; mean ageâ=â36±14.2 years) diagnosed with MDD and 314 healthy controls (153 male and 161 female; mean ageâ=â37.9±14.2 years) from Chinese Han population were used to verify the relationship between SNPs of NPY and the pathogenesis of MDD. INTERVENTION AND OUTCOME: Ligase detection reactions were performed to detect the SNP sites of NPY. A series of statistical methods was carried out to investigate the correlation between the NPY gene SNP and MDD. RESULTS: Statistical analysis showed a significant correlation between the SNP sites rs16139 in NPY and the morbidity of depression. Patients with MDD have a lower frequency of A-allele in rs16139 in replicate samples from Chinese Han population. However, the frequency varied between male and female patients. CONCLUSION: The gene polymorphism loci rs16139 was closely related to MDD in Chinese Han population.
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Povo Asiático/genética , Transtorno Depressivo Maior/genética , Predisposição Genética para Doença , Neuropeptídeo Y/genética , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Estudos de Casos e Controles , China , Feminino , Frequência do Gene , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: Bipolar disorder patients experiencing a depressive episode (BD-dep) without an observed history of mania are often misdiagnosed and are consequently treated as having unipolar depression (UD), leading to inadequate treatment and poor outcomes. An essential solution to this problem is to identify objective biological markers that distinguish BD-dep and UD patients at an early stage. However, studies directly comparing the brain dysfunctions associated with BD-dep and UD are rare. More importantly, the specificity of the differences in brain activity between these mental disorders has not been examined. With whole-brain regional homogeneity analysis and region-of-interest (ROI) based receiver operating characteristic (ROC) analysis, we aimed to compare the resting-state brain activity of BD-dep and UD patients. Furthermore, we examined the specific differences and whether these differences were attributed to the brain abnormality caused by BD-dep, UD, or both. METHODS: Twenty-one bipolar and 21 unipolar depressed patients, as well as 26 healthy subjects matched for gender, age, and educational levels, participated in the study. We compared the differences in the regional homogeneity (ReHo) of the BD-dep and UD groups and further identified their pathophysiological abnormality. In the brain regions showing a difference between the BD-dep and UD groups, we further conducted receptive operation characteristic (ROC) analyses to confirm the effectiveness of the identified difference in classifying the patients. RESULTS: We observed ReHo differences between the BD-dep and UD groups in the right ventrolateral middle frontal gyrus, right dorsal anterior insular, right ventral anterior insular, right cerebellum posterior gyrus, right posterior cingulate cortex, right parahippocampal gyrus, and left cerebellum anterior gyrus. Further ROI comparisons and ROC analysis on these ROIs showed that the right parahippocampal gyrus reflected abnormality specific to the BD-dep group, while the right middle frontal gyrus, the right dorsal anterior insular, the right cerebellum posterior gyrus, and the right posterior cingulate cortex showed abnormality specific to the UD group. CONCLUSIONS: We found brain regions showing resting state ReHo differences and examined their sensitivity and specificity, suggesting a potential neuroimaging biomarker to distinguish between BD-dep and UD patients. We further clarified the pathophysiological abnormality of these regions for each of the two patient populations.
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Transtorno Bipolar/diagnóstico , Transtorno Bipolar/fisiopatologia , Encéfalo/fisiopatologia , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/fisiopatologia , Descanso/fisiologia , Adulto , Transtorno Bipolar/psicologia , Transtorno Depressivo/psicologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
AIM: We sought to use a regional homogeneity (ReHo) approach as an index in resting-state functional magnetic resonance imaging (fMRI) to investigate the features of spontaneous brain activity within the default mode network (DMN) in patients suffering from bipolar depression (BD). METHODS: Twenty-six patients with BD and 26 gender-, age-, and education-matched healthy subjects participated in the resting-state fMRI scans. We compared the differences in ReHo between the two groups within the DMN and investigated the relationships between sex, age, years of education, disease duration, the Hamilton Rating Scale for Depression (HAMD) total score, and ReHo in regions with significant group differences. RESULTS: Our results revealed that bipolar depressed patients had increased ReHo in the left medial frontal gyrus and left inferior parietal lobe compared to healthy controls. No correlations were found between regional ReHo values and sex, age, and clinical features within the BD group. CONCLUSIONS: Our findings indicate that abnormal brain activity is mainly distributed within prefrontal-limbic circuits, which are believed to be involved in the pathophysiological mechanisms underlying bipolar depression.
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Transtorno Bipolar/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Adulto , Algoritmos , Transtorno Bipolar/patologia , Encéfalo/patologia , Mapeamento Encefálico/métodos , Estudos de Casos e Controles , Depressão/diagnóstico , Feminino , Lobo Frontal/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Lobo Parietal/patologia , Análise de RegressãoRESUMO
We examined resting state brain activity in the depressive phase of bipolar disorder (BD) by measuring the amplitude of low-frequency fluctuations (ALFF) in the functional magnetic resonance imaging (fMRI) signal. Unlike functional connectivity, the ALFF approach reflects local properties in specific regions and provides direct information about impaired foci. Groups of 26 patients with BD depression and 26 gender-, age-, and education-matched healthy subjects participated in fMRI scans. We examined group differences in ALFF findings as well as correlations between clinical measurements and ALFF in the regions showing significant group differences. Our results showed that patients with BD depression had significantly increased ALFF in the left insula, the right caudate nucleus, the temporal gyrus, the bilateral inferior frontal gyrus, and the posterior lobe of the cerebellum. They also had decreased ALFF in the left postcentral gyrus, the left parahippocampal gyrus, and the cerebellum. Moderate negative correlations were found between the Hamilton Depression Rating Scale score and ALFF in the left insular cortex in the patient group. These results support a model of BD that involves dysfunction in the prefrontal-limbic networks and associated striatal systems. We also demonstrated the feasibility of ALFF as a technique to investigate persistent cerebral dysfunction in BD.
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Afeto/fisiologia , Nível de Alerta/fisiologia , Transtorno Bipolar/fisiopatologia , Encéfalo/fisiopatologia , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Adulto , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/psicologia , Mapeamento Encefálico , Núcleo Caudado/fisiopatologia , Cerebelo/fisiopatologia , Córtex Cerebral/fisiopatologia , Dominância Cerebral/fisiologia , Feminino , Lobo Frontal/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/fisiopatologia , Valores de Referência , Estatística como Assunto , Adulto JovemRESUMO
Depression has been associated with reduced expression of brain-derived neurotrophic factor (BDNF) in the hippocampus. Genetic association studies of the BDNF Val66Met polymorphism (rs6265) in geriatric depression have produced inconsistent results. A meta-analysis of studies was conducted to compare the frequency of the BDNF Val66Met variant between cases with geriatric depression and age-matched controls. A total of five studies involving 523 cases with geriatric depression and 1,220 psychiatrically healthy controls was included. Met allele carriers had an increased risk for geriatric depression when compared to Val/Val homozygotes (P = 0.004, OR = 1.48, 95% CI = 1.13-1.93). Our findings suggest the BDNF Met allele may confer increased risk for depression as individual age.
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Substituição de Aminoácidos/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Depressão/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único/genética , Idoso , Humanos , Viés de PublicaçãoRESUMO
In the present study, we investigated differences in resting-state brain activity in patients with bipolar depression (BD) and unipolar depression (UD) by measuring the amplitude of low-frequency fluctuation (ALFF) of functional magnetic resonance imaging (fMRI) signals. Twenty-one BD and 21 gender-, age-, and education-matched UD patients participated in the fMRI analysis. We compared the differences in the ALFF between the two groups and investigated the correlation between clinical measurements and ALFF in the regions displaying significant group differences. BD subjects displayed significantly decreased ALFF in the left superior parietal lobule and the left posterior insula (l-PI). They also displayed increased ALFF in the right dorsal anterior insula (r-dAI) when compared to the UD group. Moderate negative correlations were found between the Hamilton Depression Rating Scale score (HAMD) and the ALFF in the l-PI for the BD (r=-0.44, P=0.02) and UD (r=-0.45, P=0.02) groups. Our results support the notion that insular subregions may contribute to the precise differentiation between BD and UD.