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1.
Curr Med Imaging ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38523520

RESUMO

OBJECTIVE: To develop and validate a radiomics-clinical nomogram for the detection of the acquired T790M mutation in patients with advanced non-small cell lung cancer (NSCLC) with resistance after the duration of first-line epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) treatment. MATERIALS AND METHODS: Thoracic CT was collected from 120 advanced NSCLC patients who suffered progression on first- or second-generation TKIs. Radiomics signatures were retrieved from the entire tumor. Pearson correlation and the least absolute shrinkage and selection operator (LASSO) regression method were adopted to choose the most suitable radiomics features. Clinical and radiological factors were assessed using univariate and multivariate analysis. Three Machine Learning (ML) models were constructed according to three classifiers, including Logistic Regression (LR), Support Vector Machine (SVM), and RandomForest (RF), combining clinical and radiomic features. A nomogram combining clinical features and the rad score signature was built. The predictive ability of the nomogram was assessed by the ROC curve, calibration curve, and decision curve analysis (DCA). RESULTS: Multivariate regression analysis showed that two clinicopathological characteristics and two radiological features were highly correlated with the acquired T790M mutation, including the progression-free survival (PFS) of first-line EGFR TKIs (P = 0.029), the initial EGFR profile (P = 0.01), vascular convergence (P = 0.043), and air bronchogram (P = 0.030). The AUCs of clinical, radiomics, and combined models using RF classifiers for T790M mutation detection were 0.951 (95% confidence interval [CI] 0.911,0.991), 0.917 (95%CI 0.856,0.978), and 0.961 (95%CI 0.927,0.995) in the training cohort, respectively, higher than those of other classifier models.The calibration curve and Hosmer-Lemeshow Test showed good calibration power, and the DCA demonstrated a significant net benefit. CONCLUSION: A radiomics-clinical nomogram based on CT radiomics proved valuable in non-invasively and efficiently predicting the acquired T790M mutation in patients who suffered progression on first-line TKIs.

2.
ACS Omega ; 8(35): 31946-31953, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37692214

RESUMO

Iron cokes were produced in an electrical furnace from a coal blend containing varying levels of added Fe2O3. The effects of Fe2O3 on the properties and structure of the iron coke were then investigated using the coke for metallurgy determination of mechanical strength, determination of coke reactivity and coke strength after the reaction, X-ray diffraction, Raman spectroscopy, and a method for quantitative analysis of the minerals in coal and coke. Further, the relationships between the properties and structures of iron coke samples were established. The results show that the addition of Fe2O3 can reduce the tumble strength, coke strength after the reaction, aromaticity, microcrystalline size, graphitization degree, crystalline volume, and carbon order degree of the iron coke and increase the abrasion resistance, coke reactivity index, and pulverization rate. Moreover, the degree of influence increases with increasing levels of added Fe2O3. The Fe2O3 is mainly transformed into metallic iron during the coking process, and part of metallic iron is converted into Fe3O4 during iron coke gasification. With an increasing Fe2O3 content, the trend of the change in the minerals from Fe to Fe3O4 becomes much more obvious, resulting in deeper influences on the iron coke thermal properties. There are obvious correlations among the iron coke reactivity and iron coke strength after the reaction and the crystalline volume, carbon order degree, and metallic iron content. It is concluded that the addition of Fe2O3 decreases the crystalline volume and carbon order degree and increases the metallic iron content, resulting in increases in abrasion resistance and coke reactivity and decreases in tumble strength and coke strength after the reaction.

3.
Lipids ; 47(3): 269-77, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22234516

RESUMO

We investigated the influence of an egg-enriched diet on plasma, hepatic and fecal lipid levels and on gene expression levels of transporters, receptors and enzymes involved in cholesterol metabolism. Sprague-Dawley rats fed an egg-enriched diet had lower plasma triglycerides, total cholesterol, low density lipoprotein (LDL)-cholesterol, hepatic triglyceride, and cholesterol concentrations, and greater plasma high-density lipoprotein cholesterol concentration, fecal neutral sterol and bile acid concentrations than those fed a plain cholesterol diet. Chicken egg yolk had no effect on sterol 12α-hydroxylase and sterol 27α-hydroxylase; but upregulated mRNA levels of hepatic LDL-receptor, cholesterol 7α-hydroxylase (CYP7A1) and lecithin cholesterol acyltransferase, and downregulated hepatic hydroxymethylglutaryl-(HMG)-CoA reductase and acyl-CoA:cholesterol acyltransferase (ACAT) after 90 days. Modification of the lipoprotein profile by an egg-enriched diet was mediated by reducing de novo cholesterol synthesis and enhancing the excretion of fecal cholesterol, via upregulation of CYP7A1 and the LDL receptor, and downregulation of HMG-CoA reductase and ACAT.


Assuntos
Colesterol/metabolismo , Ovos , Animais , Colesterol 7-alfa-Hidroxilase/genética , Colesterol 7-alfa-Hidroxilase/metabolismo , Dieta , Lipídeos/sangue , Fígado/enzimologia , Fígado/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Receptores de LDL/genética , Receptores de LDL/metabolismo , Esterol O-Aciltransferase/genética , Esterol O-Aciltransferase/metabolismo , Triglicerídeos/metabolismo
4.
Sheng Wu Gong Cheng Xue Bao ; 26(2): 194-200, 2010 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-20432938

RESUMO

We isolated the strain MBL13 with high collagenase productivity from the soil of piled up animal bones. It was identified as Bacillus cereus. We purified and characterized Bacillus cereus collagenase (BCC). The molecular weight of BCC was 38.0 kDa and the optimum temperature and pH for the enzyme activity were 40 degrees C and 8.0 respectively. The enzyme was stable when the temperature was below 50 degrees C, but only retained 10% activity when kept at 60 degrees C for 1 h. The enzyme activity was stable between pH 7.0-8.5. Some metal ions such as Ca2+, Zn2+, Mg2+ enhanced the enzyme activity, and Cu2+ brought the obvious inhibition. In addition, EDTA and EGTA could inhibit the enzyme activity. We suggested that the purified enzyme was a member of the metalloproteases. Based on the experiment of substrate specificity, we found that the purified enzyme was bone collagenolytic protease, and had a much stronger capacity of hydrolysis for type I collagen than that for type II collagen and type III collagen. By BCC hydrolyzing bone collagen, we obtained polypeptides with different chain lengths. The comparative test indicated that the hydrolysis capacity of BBC was higher than that of standard type I collagenase. The results introduced a new strain and a novel collagenolytic protease for industrial enzyme.


Assuntos
Bacillus cereus/enzimologia , Bacillus cereus/isolamento & purificação , Colagenases/biossíntese , Microbiologia do Solo , Animais , Osso e Ossos/microbiologia , Colagenases/isolamento & purificação , Hidrólise
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