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2.
Acad Radiol ; 31(5): 2074-2084, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38185571

RESUMO

RATIONALE AND OBJECTIVES: This study employed tract-based spatial statistics (TBSS) to investigate abnormalities in the white matter microstructure among children with autism spectrum disorder (ASD). Additionally, an eXtreme Gradient Boosting (XGBoost) model was developed to effectively classify individuals with ASD and typical developing children (TDC). METHODS AND MATERIALS: Multi-shell diffusion weighted images were acquired from 62 children with ASD and 44 TDC. Using the Pydesigner procedure, diffusion tensor (DT), diffusion kurtosis (DK), and white matter tract integrity (WMTI) metrics were computed. Subsequently, TBSS analysis was applied to discern differences in these diffusion parameters between ASD and TDC groups. The XGBoost model was then trained using metrics showing significant differences, and Shapley Additive explanations (SHAP) values were computed to assess the feature importance in the model's predictions. RESULTS: TBSS analysis revealed a significant reduction in axonal diffusivity (AD) in the left posterior corona radiata and the right superior corona radiata. Among the DK indicators, mean kurtosis, axial kurtosis, and kurtosis fractional anisotropy were notably increased in children with ASD, with no significant difference in radial kurtosis. WMTI metrics such as axonal water fraction, axonal diffusivity of the extra-axonal space (EAS_AD), tortuosity of the extra-axonal space (EAS_TORT), and diffusivity of intra-axonal space (IAS_Da) were significantly increased, primarily in the corpus callosum and fornix. Notably, there was no significant difference in radial diffusivity of the extra-axial space (EAS_RD). The XGBoost model demonstrated excellent classification ability, and the SHAP analysis identified EAS_TORT as the feature with the highest importance in the model's predictions. CONCLUSION: This study utilized TBSS analyses with multi-shell diffusion data to examine white matter abnormalities in pediatric autism. Additionally, the developed XGBoost model showed outstanding performance in classifying ASD and TDC. The ranking of SHAP values based on the XGBoost model underscored the significance of features in influencing model predictions.


Assuntos
Transtorno do Espectro Autista , Imagem de Tensor de Difusão , Aprendizado de Máquina , Substância Branca , Humanos , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/patologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Masculino , Feminino , Pré-Escolar , Imagem de Tensor de Difusão/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Criança , Interpretação de Imagem Assistida por Computador/métodos
3.
Front Hum Neurosci ; 17: 1303230, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38188507

RESUMO

Purpose: Presently, research concerning alterations in brain structure among individuals with attention deficit hyperactivity disorder (ADHD) predominantly focuses on entire brain volume and cortical thickness. In this study, we extend our examination to the cortical microstructure of male children with ADHD. To achieve this, we employ the gray-white matter tissue contrast (GWC) metric, allowing for an assessment of modifications in gray matter density and white matter microstructure. Furthermore, we explore the potential connection between GWC and the severity of disorder in male children by ADHD. Methods: We acquired 3DT1 sequences from the public ADHD-200 database. In this study, we conducted a comparative analysis between 43 male children diagnosed with ADHD and 50 age-matched male controls exhibiting typical development trajectories. Our investigation entailed assessing differences in GWC and cortical thickness. Additionally, we explored the potential correlation between GWC and the severity of ADHD. To delineate the cerebral landscape, each hemisphere was subdivided into 34 cortical regions using freesurfer 7.2.0. For quantification, GWC was computed by evaluating the intensity contrast of non-normalized T1 images above and below the gray-white matter interface. Results: Our findings unveiled elevated GWC within the bilateral lingual, bilateral insular, left transverse temporal, right parahippocampal and right pericalcarine regions in male children with ADHD when contrasted with their healthy counterparts. Moreover, the cortical thickness in the ADHD group no notable distinctions that of control group in all areas. Intriguingly, the GWC of left transverse temporal demonstrated a negative correlation with the extent of inattention experienced by male children with ADHD. Conclusion: Utilizing GWC as a metric facilitates a more comprehensive assessment of microstructural brain changes in children with ADHD. The fluctuations in GWC observed in specific brain regions might serve as a neural biomarker, illuminating structural modifications in male children grappling with ADHD. This perspective enriches our comprehension of white matter microstructure and cortical density in these children. Notably, the inverse correlation between the GWC of the left transverse temporal and inattention severity underscores the potential role of structural and functional anomalies within this region in ADHD progression. Enhancing our insight into ADHD-related brain changes holds significant promise in deciphering potential neuropathological mechanisms.

4.
Front Oncol ; 12: 1073983, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36713500

RESUMO

Objective: To evaluate the diagnostic ability of magnetic resonance imaging (MRI) based radiomics and traditional characteristics to differentiate between Ovarian sex cord-stromal tumors (SCSTs) and epithelial ovarian cancers (EOCs). Methods: We consecutively included a total of 148 patients with 173 tumors (81 SCSTs in 73 patients and 92 EOCs in 75 patients), who were randomly divided into development and testing cohorts at a ratio of 8:2. Radiomics features were extracted from each tumor, 5-fold cross-validation was conducted for the selection of stable features based on development cohort, and we built radiomics model based on these selected features. Univariate and multivariate analyses were used to identify the independent predictors in clinical features and conventional MR parameters for differentiating SCSTs and EOCs. And nomogram was used to visualized the ultimately predictive models. All models were constructed based on the logistic regression (LR) classifier. The performance of each model was evaluated by the receiver operating characteristic (ROC) curve. Calibration and decision curves analysis (DCA) were used to evaluate the performance of models. Results: The final radiomics model was constructed by nine radiomics features, which exhibited superior predictive ability with AUCs of 0.915 (95%CI: 0.869-0.962) and 0.867 (95%CI: 0.732-1.000) in the development and testing cohorts, respectively. The mixed model which combining the radiomics signatures and traditional parameters achieved the best performance, with AUCs of 0.934 (95%CI: 0.892-0.976) and 0.875 (95%CI: 0.743-1.000) in the development and testing cohorts, respectively. Conclusion: We believe that the radiomics approach could be a more objective and accurate way to distinguish between SCSTs and EOCs, and the mixed model developed in our study could provide a comprehensive, effective method for clinicians to develop an appropriate management strategy.

5.
J Pharm Biomed Anal ; 174: 674-682, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31288190

RESUMO

Near-infrared (NIR) spectroscopy is one of the most successful pharmaceutical process analytical tools. For botanical drug products (BDPs), many studies have applied NIR spectroscopy for rapid analysis of botanical raw materials, extracts and formulations. However, the real-time process analysis reported for BDPs was still mainly conducted on lab- or pilot- scale equipment, where some essential conditions of the materials and process parameters can be easily controlled for NIR spectral measurement. Due to the chemical and physical characteristics of the commercial production of BDPs, it is challenging to develop in-line NIR methods with enough robustness for industrial-scale application. This is the first reported case study of the development and validation of the in-line NIR method for the commercial production of BDPs, taking Compound Danshen Dripping Pill (CDDP) as an example. An in-line NIR method was developed for simultaneous measurement of the three critical quality attributes, i.e. the relative density, the moisture content and the content of 3,4-dihydroxyphenyl lactic acid (danshensu, a key active compound), during the extract concentration process. The NIR spectra and sample collection lasted for three years (67 production batches) to cover the variability of raw materials and process conditions. NIR calibration models were established respectively, with determination coefficients (r2) of 0.9905, root mean square errors of prediction (RMSEP) of 0.004 for the relative density in the range of 1.042-1.184; r2 of 0.9870, RMSEP of 1.1% for the moisture content in the range of 50.8-83.0%; r2 of 0.9870, RMSEP of 0.461 mg/g for danshensu in the range of 2.563-8.869 mg/g. Then, all the method validation parameters (accuracy, precision, range, specificity, linearity, robustness, detection and quantitation limits) were discussed according to the characteristics of the commercial production of BDPs. The NIR method development and validation strategy proposed may also be applied in the future for the commercial production of other BDPs.


Assuntos
Química Farmacêutica/métodos , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/farmacologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Algoritmos , Calibragem , Composição de Medicamentos , Lactatos/análise , Lactatos/farmacologia , Análise dos Mínimos Quadrados , Modelos Lineares , Teste de Materiais , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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