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1.
BMC Med Imaging ; 20(1): 50, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32408867

RESUMO

BACKGROUND: To investigate the ability of amide proton transfer (APT) weighted magnetic resonance imaging (MRI), arterial spin labeling (ASL), diffusion weighted imaging (DWI) and the combination for differentiating high-grade gliomas (HGGs) from low-grade gliomas (LGGs). METHODS: Twenty-seven patients including nine LGGs and eighteen HGGs underwent conventional, APT, ASL and DWI MRI with a 3.0-T MR scanner. Histogram analyses was performed and quantitative parameters including mean apparent diffusion coefficient (ADC mean), 20th-percentile ADC (ADC 20th), mean APT (APT mean), 90th-percentile APT (APT 90th), relative mean cerebral blood flow (rCBF mean) and relative 90th-percentile CBF (rCBF 90th) were compared between HGGs and LGGs. The diagnostic performance was evaluated with receiver operating characteristic (ROC) analysis of each parameter and their combination. Correlations were analyzed among the MRI parameters and Ki-67. RESULTS: The APT values were significantly higher in the HGGs compared to the LGGs (p <  0.005), whereas ADC values were significantly lower in HGGs than LGGs (P <  0.0001). The ADC 20th and APT mean had higher discrimination abilities compared with other single parameters, with the area under the ROC curve (AUC) of 0.877 and 0.840. Adding ADC parameter, the discrimination ability of APT and rCBF significantly improved. The ADC was negatively correlated with the APT and rCBF value, respectively, while APT value was positively correlated with rCBF value. Significant correlations between ADC values and Ki-67 were also observed. CONCLUSIONS: APT and DWI are valuable in differentiating HGGs from LGGs. The combination of APT, DWI and ASL imaging could improve the ability for discriminating HGGs from LGGs.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Glioma/diagnóstico por imagem , Imagem Multimodal/métodos , Adulto , Idoso , Amidas , Neoplasias Encefálicas/irrigação sanguínea , Circulação Cerebrovascular , Imagem de Difusão por Ressonância Magnética , Feminino , Glioma/irrigação sanguínea , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Curva ROC , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos , Sensibilidade e Especificidade , Marcadores de Spin
2.
Front Neuroinform ; 16: 937891, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36120083

RESUMO

Objective: To explore the feasibility of a deep learning three-dimensional (3D) V-Net convolutional neural network to construct high-resolution computed tomography (HRCT)-based auditory ossicle structure recognition and segmentation models. Methods: The temporal bone HRCT images of 158 patients were collected retrospectively, and the malleus, incus, and stapes were manually segmented. The 3D V-Net and U-Net convolutional neural networks were selected as the deep learning methods for segmenting the auditory ossicles. The temporal bone images were randomized into a training set (126 cases), a test set (16 cases), and a validation set (16 cases). Taking the results of manual segmentation as a control, the segmentation results of each model were compared. Results: The Dice similarity coefficients (DSCs) of the malleus, incus, and stapes, which were automatically segmented with a 3D V-Net convolutional neural network and manually segmented from the HRCT images, were 0.920 ± 0.014, 0.925 ± 0.014, and 0.835 ± 0.035, respectively. The average surface distance (ASD) was 0.257 ± 0.054, 0.236 ± 0.047, and 0.258 ± 0.077, respectively. The Hausdorff distance (HD) 95 was 1.016 ± 0.080, 1.000 ± 0.000, and 1.027 ± 0.102, respectively. The DSCs of the malleus, incus, and stapes, which were automatically segmented using the 3D U-Net convolutional neural network and manually segmented from the HRCT images, were 0.876 ± 0.025, 0.889 ± 0.023, and 0.758 ± 0.044, respectively. The ASD was 0.439 ± 0.208, 0.361 ± 0.077, and 0.433 ± 0.108, respectively. The HD 95 was 1.361 ± 0.872, 1.174 ± 0.350, and 1.455 ± 0.618, respectively. As these results demonstrated, there was a statistically significant difference between the two groups (P < 0.001). Conclusion: The 3D V-Net convolutional neural network yielded automatic recognition and segmentation of the auditory ossicles and produced similar accuracy to manual segmentation results.

3.
Front Psychiatry ; 11: 456, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32528327

RESUMO

OBJECTIVE: Neuroimaging-based brain signatures may be informative in identifying patients with psychosis who will respond to antipsychotics. However, signatures that inform the electroconvulsive therapy (ECT) health care professional about the response likelihood remain unclear in psychosis with radiomics strategy. This study investigated whether brain structure-based signature in the prediction of ECT response in a sample of schizophrenia patients using radiomics approach. METHODS: This high-resolution structural magnetic resonance imaging study included 57 patients at baseline. After ECT combined with antipsychotics, 28 and 29 patients were classified as responders and non-responders. Features of gray matter were extracted and compared. The logistic regression model/support vector machine (LRM/SVM) analysis was used to explore the predictive performance. RESULTS: The regularized multivariate LRM accurately discriminated responders from non-responders, with an accuracy of 90.91%. The structural features were further confirmed in the validating data set, resulting in an accuracy of 87.59%. The accuracy of the SVM in the training set was 90.91%, and the accuracy in the validation set was 91.78%. CONCLUSION: Our results support the possible use of structural brain feature-based radiomics as a potential tool for predicting ECT response in patients with schizophrenia undergoing antipsychotics, paving the way for utilization of markers in psychosis.

4.
Schizophr Res ; 208: 160-166, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30967317

RESUMO

OBJECTIVE: We aimed to evaluate the functional network properties in first-episode schizophrenia (SZ) patients at baseline and after 4-months treatment with second-generation antipsychotic drugs. METHODS: Resting-state functional magnetic resonance imaging and graph theory approaches were utilized to evaluate the functional integration and segregation of brain networks in 36 first-episode patients (20 male/16 female) with SZ and 36 age and sex matched healthy controls (20 male/16 female). RESULTS: Compared with healthy controls, SZ at baseline showed lower clustering coefficient (Cp) and local network efficiency (Eloc), and this abnormal pattern was modulated with treatment of antipsychotic drugs at follow-up. Longitudinally, the increase of Cp was associated with the improvement of negative symptom. We found that the strength of functional connectivity between brain regions were significantly increased in three connections after treatment, mainly involving the frontal, parietal and occipital lobes. CONCLUSION: The current study suggested that antipsychotic drugs could modulate the faulty local clustering of the functional connectome in SZ. Furthermore, Cp, the parameter that reflects local clustering of topological organization, demonstrated the potential to be a connectome-based biomarker of treatment response to second-generation antipsychotics in patients with SZ.


Assuntos
Antipsicóticos/uso terapêutico , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Imageamento por Ressonância Magnética , Esquizofrenia/tratamento farmacológico , Esquizofrenia/fisiopatologia , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiopatologia , Descanso , Esquizofrenia/diagnóstico por imagem , Resultado do Tratamento , Adulto Jovem
5.
Brain Behav ; 9(2): e01211, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30701701

RESUMO

INTRODUCTION: Treatment response at an early stage of schizophrenia is of considerable value with regard to future management of the disorder; however, there are currently no biomarkers that can inform physicians about the likelihood of response. OBJECTS: We aim to develop and validate regional brain activity derived from functional magnetic resonance imaging (fMRI) as a potential signature to predict early treatment response in schizophrenia. METHODS: Amplitude of low-frequency fluctuation (ALFF) was measured at the start of the first/single episode resulting in hospitalization. Inpatients were included in a principal dataset (n = 79) and a replication dataset (n = 44). Two groups of healthy controls (n = 87; n = 106) were also recruited for each dataset. The clinical response was assessed at discharge from the hospital. The predictive capacity of normalized ALFF in patients by healthy controls, ALFFratio , was evaluated based on diagnostic tests and clinical correlates. RESULTS: In the principal dataset, responders exhibited increased baseline ALFF in the left postcentral gyrus/inferior parietal lobule relative to non-responders. ALFFratio of responders before treatment was significantly higher than that of non-responders (p < 0.001). The area under the receiver operating characteristic curve was 0.746 for baseline ALFFratio to distinguish responders from non-responders, and the sensitivity, specificity, and accuracy were 72.7%, 68.6%, and 70.9%, respectively. Similar results were found in the independent replication dataset. CONCLUSIONS: Baseline regional activity of the brain seems to be predictive of early response to treatment for schizophrenia. This study shows that psycho-neuroimaging holds promise for influencing the clinical treatment and management of schizophrenia.


Assuntos
Encéfalo/fisiopatologia , Hospitalização , Imageamento por Ressonância Magnética/métodos , Esquizofrenia , Adulto , Cuidado Periódico , Feminino , Humanos , Masculino , Neuroimagem/métodos , Avaliação de Resultados em Cuidados de Saúde , Prognóstico , Curva ROC , Esquizofrenia/diagnóstico , Esquizofrenia/fisiopatologia , Esquizofrenia/terapia
6.
Front Neurosci ; 13: 424, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31130837

RESUMO

Background: Hippocampal dysconnectivity has been detected in schizophrenia patients with auditory verbal hallucinations (AVHs). Neuroanatomical evidence has indicated distinct sub-regions in the hippocampus, but which sub-regions within the hippocampus may emerge dysfunction in the brain network, and the relationship between connection strength and the severity of this debilitating disorder have yet to be revealed. Masked independent component analysis (mICA), i.e., ICA restricted to a defined region of interest, can provide insight into observing local functional connectivity in a particular brain region. We aim to map out the sub-regions in the hippocampus with dysconnectivity linked to AVHs in schizophrenia. Methods: In this functional magnetic resonance imaging study of schizophrenia patients with (n = 57) and without (n = 83) AVHs, and 71 healthy controls, we first examined hippocampal connectivity using mICA, and then the correlation between connection metric and clinical severity was generated. Results: As compared with patients without AVHs, mICA showed a group of hyper-connections for the left middle part, as well as another group of hypo-connections for the bilateral antero-lateral and right antero-medial parts in patients with AVHs. Connectivity was linked to the clinical symptoms scores in the sample of patients with AVHs. Conclusion: These findings demonstrate that the left middle part is more densely connected, but the bilateral antero-lateral and right antero-medial parts are more sparsely connected in schizophrenia patients with AVHs. The findings in the present study show proof of precious location in the hippocampus mediating the neural mechanism behind AVHs in schizophrenia.

7.
J Psychiatr Res ; 116: 126-132, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31233895

RESUMO

Despite evidence of structural brain abnormalities in schizophrenia, the current study aimed to explore the effects of antipsychotic treatment on gray matter (GM) volume using structural magnetic resonance imaging (MRI) and investigate the relationship between brain structure and treatment response. The GM volumes of 33 patients with first-episode schizophrenia were calculated with voxel-based morphometry (VBM), with 33 matched healthy controls. Longitudinal volume changes within subjects after 4-month antipsychotic treatment were also evaluated. Correlation between volumetric changes and clinical symptoms derived from the Positive and Negative Syndrome Scale (PANSS) were further investigated. Compared with healthy controls, decreased GM volumes in the frontal gyrus were observed in schizophrenia patients. After 4-month treatment, patients showed significantly decreased GM volume primarily in the bilateral frontal, temporal and left parietal brain regions. In addition, the GM volume changes of the left postcentral gyrus was positively correlated with negative symptoms improvement, and the correlation analysis revealed the total PANSS scores changes were associated with GM volume changes in the right inferior frontal gyrus and the right superior temporal gyrus. Besides, non-responders had reduced GM volume in the bilateral middle frontal gyrus and the right superior frontal gyrus compared with responders and healthy controls. Our results suggest that the abnormality in the right frontal gyrus exists in the early stage of schizophrenia. Moreover, the relationship between antipsychotics and structural changes was identified. The GM volume might have the potential to reflect the symptom improvement in schizophrenia patients. And MRI may assist in predicting the antipsychotic treatment response in first-episode schizophrenia patients.


Assuntos
Antipsicóticos/farmacologia , Substância Cinzenta/efeitos dos fármacos , Substância Cinzenta/patologia , Avaliação de Resultados em Cuidados de Saúde , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/patologia , Esquizofrenia/tratamento farmacológico , Esquizofrenia/patologia , Adulto , Seguimentos , Substância Cinzenta/diagnóstico por imagem , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/fisiopatologia , Adulto Jovem
8.
Huan Jing Ke Xue ; 36(4): 1208-16, 2015 Apr.
Artigo em Zh | MEDLINE | ID: mdl-26164892

RESUMO

Based on the collected activity data, the 2012 emission inventory of crop residues field burning in Sichuan province was developed through the emission factor approach. Besides, the temporal and spatial distribution of pollutant emissions was also analysed in this paper. The results showed that the total emissions of SO2, NO(x), NH3, CH4, NMVOC, CO, PM2.5, EC and OC from crop residues field burning in Sichuan province in the year of 2012 were 1 210, 12 185, 2 827, 20 659, 40 463, 292 671, 39 277, 1 984 and 10 215 t, respectively; The rice straw, wheat straw, corn straw and oil rape straw were four major contributors to pollutant emissions, with a total contribution about 88% - 94%; Crop residues field burning emissions were affected by agricultural harvesting. Temporally, the emissions were concentrated in July and August with a small peak in May; Spatially, the Chengdu plain, the Northern area and the Eastern area of Sichuan province were the highest emission areas, while the Western area had relatively low emissions; The key uncertain sources included emission factors and parameters used for estimating crop burning amounts.


Assuntos
Poluentes Atmosféricos/análise , Produtos Agrícolas , Monitoramento Ambiental , Agricultura , Brassica rapa , China , Incêndios , Oryza , Triticum , Zea mays
9.
Huan Jing Ke Xue ; 34(12): 4535-42, 2013 Dec.
Artigo em Zh | MEDLINE | ID: mdl-24640887

RESUMO

Based on Sichuan province environmental statistical survey data and other relevant activity data, volatile organic compounds (VOCs) emissions from typical anthropogenic sources in Sichuan province were calculated for the year of 2011 by applying the emission factor method. Besides, ozone and secondary organic aerosol formation potentials of these typical anthropogenic sources were discussed. The total VOC emission from these sources was about 482 kt in Sichuan province, biomass burning, solvent utilization, industrial processes, storage and distribution of fuel, and fossil fuel combustion contributed 174 kt, 153 kt, 121 kt, 21 kt and 13 kt, respectively; architecture wall painting, furniture coating, wood decoration painting and artificial board were the major emission sectors of the solvent utilization; while for the industrial processes, 19.4% of VOCs emission was from the wine industry. Chengdu was the largest contributor compared to the other cities in Sichuan, whose VOCs emission from these typical anthropogenic sources in 2011 was 112 kt. OFP of these sources was 1,930 kt altogether. Solvent utilization contributed 50.5% of the total SOA formation potentials, biomass burning and industrial processes both contributed about 23% , with storage and distribution of fuel and fossil fuel combustion accounting for 1% and 1.4%, respectively.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Compostos Orgânicos Voláteis/análise , Aerossóis/análise , China , Cidades , Ozônio/análise
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