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1.
J Magn Reson Imaging ; 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38031466

RESUMO

BACKGROUND: Glioma grading transformed in World Health Organization (WHO) 2021 CNS tumor classification, integrating molecular markers. However, the impact of this change on radiomics-based machine learning (ML) classifiers remains unexplored. PURPOSE: To assess the performance of ML in classifying glioma tumor grades based on various WHO criteria. STUDY TYPE: Retrospective. SUBJECTS: A neuropathologist regraded gliomas of 237 patients into WHO 2016 and 2021 from 2007 criteria. FIELD STRENGTH/SEQUENCE: Multicentric 0.5 to 3 Tesla; pre- and post-contrast T1-weighted, T2-weighted, and fluid-attenuated inversion recovery. ASSESSMENT: Radiomic features were selected using random forest-recursive feature elimination. The synthetic minority over-sampling technique (SMOTE) was implemented for data augmentation. Stratified 10-fold cross-validation with and without SMOTE was used to evaluate 11 classifiers for 3-grade (2, 3, and 4; WHO 2016 and 2021) and 2-grade (low and high grade; WHO 2007 and 2021) classification. Additionally, we developed the models on data randomly divided into training and test sets (mixed-data analysis), or data divided based on the centers (independent-data analysis). STATISTICAL TESTS: We assessed ML classifiers using sensitivity, specificity, accuracy, and the area under the receiver operating characteristic curve (AUC). Top performances were compared with a t-test and categorical data with the chi-square test using a significance level of P < 0.05. RESULTS: In the mixed-data analysis, Stacking Classifier without SMOTE achieved the highest accuracy (0.86) and AUC (0.92) in 3-grade WHO 2021 grouping. The results of WHO 2021 were significantly better than WHO 2016 (P-value<0.0001). In the 2-grade analysis, ML achieved 1.00 in all metrics. In the independent-data analysis, ML classifiers showed strong discrimination between grade 2 and 4, despite lower performance metrics than the mixed analysis. DATA CONCLUSION: ML algorithms performed better in glioma tumor grading based on WHO 2021 criteria. Nonetheless, the clinical use of ML classifiers needs further investigation. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

2.
Eur J Radiol ; 167: 111051, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37632999

RESUMO

PURPOSE: Magnetic resonance imaging (MRI) can reduce the need for unnecessary invasive diagnostic tests by nearly half. In this meta-analysis, we investigated the diagnostic accuracy of intravoxel incoherent motion modeling (IVIM) and dynamic contrast-enhanced (DCE) MRI in differentiating benign from malignant breast lesions. METHOD: We systematically searched PubMed, EMBASE, and Scopus. We included English articles reporting diagnostic accuracy for both sequences in differentiating benign from malignant breast lesions. Articles were assessed by quality assessment of diagnostic accuracy studies-2 (QUADAS-2) questionnaire. We used a bivariate effects model for standardized mean difference (SMD) analysis and diagnostic test accuracy analysis. RESULTS: Ten studies with 537 patients and 707 (435 malignant and 272 benign) lesions were included. The D, f, Ktrans, and Kep mean values significantly differ between benign and malignant lesions. The pooled sensitivity (95 % confidence interval) and specificity were 86.2 % (77.9 %-91.7 %) and 70.3 % (56.5 %-81.1 %) for IVIM, and 93.8 % (85.3 %-97.5 %) and 68.1 % (52.7 %-80.4 %) for DCE, respectively. Combined IVIM and DCE depicted the highest area under the curve of 0.94, with a sensitivity and specificity of 91.8 % (82.8 %-96.3 %) and 87.6 % (73.8 %-94.7 %), respectively. CONCLUSIONS: Combined IVIM and DCE had the highest diagnostic accuracy, and multiparametric MRI may help reduce unnecessary benign breast biopsy.


Assuntos
Meios de Contraste , Imagem de Difusão por Ressonância Magnética , Humanos , Imagem de Difusão por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Mama/diagnóstico por imagem , Sensibilidade e Especificidade , Movimento (Física)
3.
Cell Physiol Biochem ; 56(6): 707-729, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36537138

RESUMO

Natural resources have long played a prominent part in conventional treatments as a parental source due to their multifaceted functions and lesser side effects. The diversity of marine products is a significant source of possible bioactive chemical compounds with a wide range of potential medicinal applications. Marine organisms produce natural compounds and new drugs with unique properties are produced from these compounds. A lot of bioactive compounds with medicinal properties are extracted from marine invertebrates, including Peptides, Alkaloids, Terpenoids, Steroids. Thus, it can be concluded that marine ecosystems are endowed with natural resources that have a wide range of medicinal properties, and it is important to examine the therapeutic and pharmacological capabilities of these molecules. So, finding particular inhibitors of the COVID-19 in natural compounds will be extremely important. Natural ingredients, in this light, could be a valuable resource in the progression of COVID-19 therapeutic options. Controlling the immunological response in COVID-19 patients may be possible by addressing the PI3K/Akt pathway and regulating T cell responses. T cell effector activity can be improved by preventing anti-viral exhaustion by suppressing PI3K and Akt during the early anti-viral response. The diversity of marine life is a significant supply of potentially bioactive chemical compounds with a broad range of medicinal uses. In this study, some biologically active compounds from marine organisms capable of inhibiting PI3K/AKT and the possible therapeutic targets from these compounds in viral infection COVID-19 have been addressed.


Assuntos
Produtos Biológicos , COVID-19 , Humanos , Inibidores da Angiogênese , Organismos Aquáticos/química , Organismos Aquáticos/metabolismo , Produtos Biológicos/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , SARS-CoV-2/efeitos dos fármacos
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