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1.
BMC Med Imaging ; 23(1): 138, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37737166

RESUMO

BACKGROUND: This study aimed to develop a computed tomography (CT) model to predict Ki-67 expression in hepatocellular carcinoma (HCC) and to examine the added value of radiomics to clinico-radiological features. METHODS: A total of 208 patients (training set, n = 120; internal test set, n = 51; external validation set, n = 37) with pathologically confirmed HCC who underwent contrast-enhanced CT (CE-CT) within 1 month before surgery were retrospectively included from January 2014 to September 2021. Radiomics features were extracted and selected from three phases of CE-CT images, least absolute shrinkage and selection operator regression (LASSO) was used to select features, and the rad-score was calculated. CE-CT imaging and clinical features were selected using univariate and multivariate analyses, respectively. Three prediction models, including clinic-radiologic (CR) model, rad-score (R) model, and clinic-radiologic-radiomic (CRR) model, were developed and validated using logistic regression analysis. The performance of different models for predicting Ki-67 expression was evaluated using the area under the receiver operating characteristic curve (AUROC) and decision curve analysis (DCA). RESULTS: HCCs with high Ki-67 expression were more likely to have high serum α-fetoprotein levels (P = 0.041, odds ratio [OR] 2.54, 95% confidence interval [CI]: 1.04-6.21), non-rim arterial phase hyperenhancement (P = 0.001, OR 15.13, 95% CI 2.87-79.76), portal vein tumor thrombus (P = 0.035, OR 3.19, 95% CI: 1.08-9.37), and two-trait predictor of venous invasion (P = 0.026, OR 14.04, 95% CI: 1.39-144.32). The CR model achieved relatively good and stable performance compared with the R model (AUC, 0.805 [95% CI: 0.683-0.926] vs. 0.678 [95% CI: 0.536-0.839], P = 0.211; and 0.805 [95% CI: 0.657-0.953] vs. 0.667 [95% CI: 0.495-0.839], P = 0.135) in the internal and external validation sets. After combining the CR model with the R model, the AUC of the CRR model increased to 0.903 (95% CI: 0.849-0.956) in the training set, which was significantly higher than that of the CR model (P = 0.0148). However, no significant differences were found between the CRR and CR models in the internal and external validation sets (P = 0.264 and P = 0.084, respectively). CONCLUSIONS: Preoperative models based on clinical and CE-CT imaging features can be used to predict HCC with high Ki-67 expression accurately. However, radiomics cannot provide added value.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Antígeno Ki-67 , Estudos Retrospectivos , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X
2.
Eur Radiol ; 33(12): 8936-8947, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37368104

RESUMO

OBJECTIVES: To evaluate the performance of a radiomics nomogram developed based on gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (Gd-EOB-DTPA) MRI for preoperative prediction of microvascular invasion (MVI) of hepatocellular carcinoma (HCC), and to identify patients who may benefit from the postoperative adjuvant transarterial chemoembolization (PA-TACE). METHODS: A total of 260 eligible patients were retrospectively enrolled from three hospitals (140, 65, and 55 in training, standardized external, and non-standardized external validation cohort). Radiomics features and image characteristics were extracted from Gd-EOB-DTPA MRI image before hepatectomy for each lesion. In the training cohort, a radiomics nomogram which incorporated the radiomics signature and radiological predictors was developed. The performance of the radiomics nomogram was assessed with respect to discrimination calibration, and clinical usefulness with external validation. A score (m-score) was constructed to stratify the patients and explored whether it could accurately predict patient who benefit from PA-TACE. RESULTS: A radiomics nomogram integrated with the radiomics signature, max-D(iameter) > 5.1 cm, peritumoral low intensity (PTLI), incomplete capsule, and irregular morphology had favorable discrimination in the training cohort (AUC = 0.982), the standardized external validation cohort (AUC = 0.969), and the non-standardized external validation cohort (AUC = 0.981). Decision curve analysis confirmed the clinical usefulness of the novel radiomics nomogram. The log-rank test revealed that PA-TACE significantly decreased the early recurrence in the high-risk group (p = 0.006) with no significant effect in the low-risk group (p = 0.270). CONCLUSIONS: The novel radiomics nomogram combining the radiomics signature and clinical radiological features achieved preoperative non-invasive MVI risk prediction and patient benefit assessment after PA-TACE, which may help clinicians implement more appropriate interventions. CLINICAL RELEVANCE STATEMENT: Our radiomics nomogram could represent a novel biomarker to identify patients who may benefit from the postoperative adjuvant transarterial chemoembolization, which may help clinicians to implement more appropriate interventions and perform individualized precision therapies. KEY POINTS: • The novel radiomics nomogram developed based on Gd-EOB-DTPA MRI achieved preoperative non-invasive MVI risk prediction. • An m-score based on the radiomics nomogram could stratify HCC patients and further identify individuals who may benefit from the PA-TACE. • The radiomics nomogram could help clinicians to implement more appropriate interventions and perform individualized precision therapies.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/irrigação sanguínea , Nomogramas , Estudos Retrospectivos
3.
Angew Chem Int Ed Engl ; 62(19): e202302466, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36892310

RESUMO

Ethylene glycol is a useful organic compound and chemical intermediate for manufacturing various commodity chemicals of industrial importance. Nevertheless, the production of ethylene glycol in a green and safe manner is still a long-standing challenge. Here, we established an integrated, efficient pathway for oxidizing ethylene into ethylene glycol. Mesoporous carbon catalyst produces H2 O2 , and titanium silicalite-1 catalyst would subsequently oxidize ethylene into ethylene glycol with the in situ generated H2 O2 . This tandem route presents a remarkable activity, i.e., 86 % H2 O2 conversion with 99 % ethylene glycol selectivity and 51.48 mmol gecat -1 h-1 production rate at 0.4 V vs. reversible hydrogen electrode. Apart from generated H2 O2 as an oxidant, there exists ⋅OOH intermediate which could omit the step of absorbing and dissociating H2 O2 over titanium silicalite-1, showing faster reaction kinetics compared to the ex situ one. This work not only provides a new idea for yielding ethylene glycol but also demonstrates the superior of in situ generated H2 O2 in tandem route.

4.
Abdom Radiol (NY) ; 47(10): 3468-3477, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35842888

RESUMO

PURPOSE: This study aimed to establish a reliable diagnostic score model for the preoperative determination of pathological grade in HCC based on gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) enhanced MRI and biochemical indicators. METHODS: In this retrospective study, we analyzed 139 patients with HCC who underwent Gd-EOB-DTPA MRI between 2014 and 2020, including an establishment cohort of 76 patients and a validation cohort of 63 patients. Based on the imaging features demonstrated on Gd-EOB-DTPA MRI images and biochemical indicators of the establishment cohort, a scoring model based on logistic regression was developed, and compared with postoperative pathological findings in terms of effective determination of pathological grade. The validity of the scoring model was assessed by ROC curves and an independent external validation cohort. RESULTS: Three parameters related to pathological grades were identified, including maximum diameter of the tumor, peritumoral hypointensity in the hepatobiliary phase, and [alkaline phosphatase (U/L) + gamma glutamyl transpeptidase (U/L)]/ lymphocyte count (× 109/L) (AGLR) ratios. Based on these three parameters, a scoring model was developed. ROC curve showed that a score of > 5 was set as the threshold for determining pathological grades with accuracy, sensitivity, specificity, PPV, and NPV of 89.5%, 75.0%, 95.1%, 85.7%, and 90.7%, respectively. CONCLUSION: The study provided the groundwork for a promising and easily implementable scoring model for preoperative determination of HCC pathological grades, for which further validation should be pursued.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Meios de Contraste , Gadolínio DTPA , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos
5.
Eur Radiol ; 32(6): 4186-4197, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35048134

RESUMO

OBJECTIVES: This study aimed to establish a reliable diagnostic scoring model for the preoperative prediction of microvascular invasion (MVI) in hepatocellular carcinoma (HCC) patients based on gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) and biochemical indicators. METHODS: This retrospective study included 129 patients with HCC at our hospital from 2014 to 2020. Based on the intratumoral and peritumoral features on Gd-EOB-DTPA MRI and biochemical indicators, a scoring model was developed for preoperative prediction of MVI, and examined for diagnostic efficacy according to postoperative pathological results. The scoring model was further externally validated in an independent cohort of 63 HCC patients. RESULTS: Logistic regression analysis was performed to identify five parameters related to MVI, including maximum tumor diameter, peritumoral low intensity in the hepatobiliary phase, incomplete capsule, apparent diffusion coefficient (ADC), and [alkaline phosphatase (ALP) (U/L) + gamma-glutamyl transpeptidase (GGT) (U/L)] / lymphocyte count (× 109/L) ratio (AGLR). Based on these five parameters, a scoring model was developed, and the accuracy, sensitivity, specificity, PPV, and NPV in predicting MVI were 93.6%, 94.7%, 93.2%, 85.7%, and 97.6%, respectively, with a score > 8 set as the threshold. CONCLUSION: The scoring model based on Gd-EOB-DTPA MRI and biochemical indicators provides a reliable tool for preoperative prediction of MVI in HCC patients. KEY POINTS: • The scoring model based on Gd-EOB-DTPA MRI and biochemical indicators is practical for preoperative prediction of MVI in HCC patients. • AGLR is an independent risk factor for MVI. • The scoring model could help implement more appropriate interventions, potentially leading to precise and individualized treatments based on the biological characteristics of the tumor.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Meios de Contraste , Gadolínio DTPA , Humanos , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos
6.
Histochem Cell Biol ; 153(4): 257-269, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32062699

RESUMO

To master the effect of small nucleolar RNA, SNORD44, on the proliferation, apoptosis and invasion of glioma cells and its relevant mechanism. SNORD44 and GAS5 expression in glioma tissues and cells was detected through qRT-PCR. Then, the glioma cell lines (U87 and U251) were divided into different groups with different treatments. Cell proliferation was determined by MTT assay, while the abilities of the cell migration and invasion were measured by wound-healing test and Transwell assay, respectively. Cell apoptosis were detected by flow cytometry and TUNEL assay. The expression of apoptosis proteins was quantified through Western blotting. Finally, the xenograft models were established on nude mice to investigate the effects of SNORD44 on the growth of glioma and the expressions of Ki67, MMP2 and MMP9 in vivo. SNORD44 and GAS5 were down-regulated in glioma tissues and cells in a positive correlation. Either SNORD44 or GAS5 overexpression decreased the proliferation, invasion and migration of U87 and U251 cells with the up-regulation of apoptosis rates, as well as the expressions of cleaved PARP, caspase 3, caspase 8 and caspase 9. Moreover, the in vivo experiment showed that overexpression of SNORD44 blocked the growth of glioma xenograft in nude mice accompanying with the inhibition of Ki67, MMP2 and MMP9 expressions. The combination overexpression of SNORD44 and GAS5 gained better inhibitory effects on glioma cells. Overexpression of SNORD44 and GAS5 activate the caspase-dependent apoptosis pathway to facilitate the apoptosis with the inhibited proliferation, invasion and migration of glioma cells.


Assuntos
Apoptose , Neoplasias do Sistema Nervoso Central/metabolismo , Neoplasias do Sistema Nervoso Central/patologia , Glioma/metabolismo , Glioma/patologia , RNA Nucleolar Pequeno/metabolismo , Animais , Linhagem Celular , Proliferação de Células , Neoplasias do Sistema Nervoso Central/genética , Feminino , Glioma/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Nucleolar Pequeno/genética
7.
Biosci Rep ; 39(12)2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31729531

RESUMO

Colorectal cancer (CRC) remains the candidate for one of the typical types of malignant tumors of in gastrointestinal tract all around the world, which leads to tremendous death and ranks as the top leading death of cancer. Recently, microRNAs have emerged as double-edged sword in numerous cancers. This investigation aims to discuss the regulative role of microRNA-574-3p (miR-574-3p), elucidating its molecular mechanism and clinical significance in CRC. Herein, it revealed to us that miR-574-3p was lowly expressed in CRC tissues in comparison with the matched paracarcinoma tissues. In addition, transfection of SW480 and HT29 cells with miR-574-3p mimics prohibited the post-transcriptional expression of Cyclin D2 (CCND2), which then significantly blocked cell growth and cell migration, yet triggered cell apoptosis. Also, dual-luciferase reporter assays proved the role of CCND2 as the targeted gene for miR-574-3p. miR-574-3p overexpression prohibited the activity of CCND2 in SW480 and HT29 cells. Silencing of CCND2 in SW480 and HT29 CRC cell lines leading to reduced cell proliferative and migrative rates, and enhanced apoptotic rate. The suppressive effects of elevation of miR-574-3p on the proliferation of the human CRC cells and promotive effects on cell apoptosis by targeting CCND2 were further illustrated in the in vitro studies. Thus, we hypothesize that miR-574-3p may be served as a prospective therapeutic candidate for CRC.


Assuntos
Proliferação de Células/genética , Neoplasias Colorretais/genética , Ciclina D2/genética , MicroRNAs/genética , Idoso , Apoptose/genética , Movimento Celular/genética , Neoplasias Colorretais/patologia , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Células HCT116 , Células HT29 , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia
8.
Angew Chem Int Ed Engl ; 57(6): 1632-1635, 2018 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29292571

RESUMO

The development of highly selective, chemically stable and moisture-resistant adsorbents is a key milestone for gas separation. Porous carbons featured with random orientation and cross-linking of turbostratic nanodomains usually have a wide distribution of micropores. Here we have developed a thermoregulated phase-transition-assisted synthesis of carbon nanoplates with more than 80 % sp2 carbon, unimodal ultramicropore and a controllable thickness. The thin structure allows oriented growth of carbon crystallites, and stacking of crystallites in nearly parallel orientation are responsible for the single size of the micropores. When used for gas separation from CH4 , carbon nanoplates exhibit high uptakes (5.2, 5.3 and 5.1 mmol g-1 ) and selectivities (7, 71 and 386) for CO2 , C2 H6 and C3 H8 under ambient conditions. The dynamic adsorption capacities are close to equilibrium uptakes of single components, further demonstrating superiority of carbon nanoplates in terms of selectivity and sorption kinetics.

9.
ACS Appl Mater Interfaces ; 5(6): 2208-13, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23452385

RESUMO

Porous carbon materials with large pore volume are crucial in loading insulated sulfur with the purpose of achieving high performance for lithium-sulfur batteries. In our study, peapodlike mesoporous carbon with interconnected pore channels and large pore volume (4.69 cm(3) g(-1)) was synthesized and used as the matrix to fabricate carbon/sulfur (C/S) composite which served as attractive cathodes for lithium-sulfur batteries. Systematic investigation of the C/S composite reveals that the carbon matrix can hold a high but suitable sulfur loading of 84 wt %, which is beneficial for improving the bulk density in practical application. Such controllable sulfur-filling also effectively allows the volume expansion of active sulfur during Li(+) insertion. Moreover, the thin carbon walls (3-4 nm) of carbon matrix not only are able to shorten the pathway of Li(+) transfer and conduct electron to overcome the poor kinetics of sulfur cathode, but also are flexible to warrant structure stability. Importantly, the peapodlike carbon shell is beneficial to increase the electrical contact for improving electronic conductivity of active sulfur. Meanwhile, polymer modification with polypyrrole coating layer further restrains polysulfides dissolution and improves the cycle stability of carbon/sulfur composites.


Assuntos
Carbono/química , Fontes de Energia Elétrica , Eletrodos , Lítio/química , Enxofre/química , Eletroquímica/métodos , Porosidade
10.
J Colloid Interface Sci ; 254(1): 153-7, 2002 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-12702436

RESUMO

Polycondensation of a cresol mixture (C(m)) with formaldehyde (F) in basic aqueous solutions leads to formation of highly cross-linked C(m)F aquagels that can be supercritically dried with carbon dioxide to form organic C(m)F aerogels. Aerogels synthesized with different catalyst contents and reactant concentrations are characterized by low-temperature nitrogen adsorption. The present experimental results suggest that the C(m)F aerogels are typical mesoporous materials and have almost no micropores in bulk. The microstructure of the organic C(m)F aerogels can be controlled and tailored effectively by varying synthesis conditions during the initial sol-gel process. C(m)F organic aerogels with specific surface area as high as 627 m(2)/g and corresponding pore volume 2.06 ml/g have been obtained with a dominant pore size of 30 nm. C(m)F organic aerogels with peaky pore size distributions concentrated at 11 nm have also been prepared.

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