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1.
Chem Commun (Camb) ; 60(52): 6635-6638, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38853651

RESUMEN

Ultrathin catalysts predominantly expose surface active atoms to deliver promising applications in oxygen reduction reactions (ORRs). However, they are commonly synthesized at high reaction temperatures, with tedious chemical routes involved. Herein, we report a low temperature (273 K) electric field driven route to synthesize zigzag-surface ultrathin copper nanowires. Interestingly, the ultrathin copper nanowires assemble into three-dimensional microspheres, which exhibit hydrophobic-aerophilic features, eventually resulting in good ORR activities. The aerophilicity and hydrophobicity of copper nanowires are related to their Cu2O active sites and hierarchical protuberances, respectively. Our findings open a new door to grow ultrathin catalysts for new energy storage systems.

2.
Front Pharmacol ; 14: 1275113, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38094884

RESUMEN

Chinese olive is a popular fruit with a long history of cultivation and consumption. As a fruit with edible, nutritional, and even medicinal value, the Chinese olive has attracted increased interest from both nutrition researchers and health-conscious consumers. Chinese olive is a rich nutrient source, including essential and non-essential amino acids, various fatty acids, organic acids, vitamins, microelements, and high-quality dietary fibers. It is also an important natural source of phytochemicals such as phenolic acids, flavonoids, phenylpropanoids, and other bioactive compounds. The nutritional and phytochemical compounds obtained from the Chinese olive exhibit unique and potent biological activities, explaining its various benefits to human health, including anti-Helicobacter pylori, anti-influenza, anti-diabetes, anti-inflammatory, anti-tumor effects, among others. This review focuses on recent studies on Chinese olives and aims to summarize the major advances in their nutritional value, phytochemical composition, health benefits, and practical applications. It provides a reference for further research on Chinese olives and their properties and the development of novel functional products.

3.
Gastroenterol Rep (Oxf) ; 11: goac081, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36686571

RESUMEN

Background: In colonoscopy screening for colorectal cancer, human vision limitations may lead to higher miss rate of lesions; artificial intelligence (AI) assistance has been demonstrated to improve polyp detection. However, there still lacks direct evidence to demonstrate whether AI is superior to trainees or experienced nurses as a second observer to increase adenoma detection during colonoscopy. In this study, we aimed to compare the effectiveness of assistance from AI and human observer during colonoscopy. Methods: A prospective multicenter randomized study was conducted from 2 September 2019 to 29 May 2020 at four endoscopy centers in China. Eligible patients were randomized to either computer-aided detection (CADe)-assisted group or observer-assisted group. The primary outcome was adenoma per colonoscopy (APC). Secondary outcomes included polyp per colonoscopy (PPC), adenoma detection rate (ADR), and polyp detection rate (PDR). We compared continuous variables and categorical variables by using R studio (version 3.4.4). Results: A total of 1,261 (636 in the CADe-assisted group and 625 in the observer-assisted group) eligible patients were analysed. APC (0.42 vs 0.35, P = 0.034), PPC (1.13 vs 0.81, P < 0.001), PDR (47.5% vs 37.4%, P < 0.001), ADR (25.8% vs 24.0%, P = 0.464), the number of detected sessile polyps (683 vs 464, P < 0.001), and sessile adenomas (244 vs 182, P = 0.005) were significantly higher in the CADe-assisted group than in the observer-assisted group. False detections of the CADe system were lower than those of the human observer (122 vs 191, P < 0.001). Conclusions: Compared with the human observer, the CADe system may improve the clinical outcome of colonoscopy and reduce disturbance to routine practice (Chictr.org.cn No.: ChiCTR1900025235).

4.
Zhonghua Gan Zang Bing Za Zhi ; 20(11): 822-7, 2012 Nov.
Artículo en Zh | MEDLINE | ID: mdl-23206300

RESUMEN

OBJECTIVE: To investigate the effects of cAMP-response element binding protein-1 (CREB-1) on transforming growth factor-b3 (TGF b3) mRNA expression and promoter activity in hepatic stellate cells (HSCs). METHODS: Freshly isolated HSCs from rats were divided into six groups: CREB-1 expression plasmid transfected group (C), siRNA-CREB-1 plasmid transfected group (S), negative control group (N), forskolin treated group (F), H-89 treated group (H), and blank group (B). Rats in each group were further sub-divided according to whether (+) or not (-) they were exposed to exogenous TGF b3. TGF b3 mRNA expression was measured by real time quantitative PCR. HSCs of the C, S, N, F, H and B groups were transfected with the TGF b3 promoter luciferase reporter plasmid (PGL3-TGF b3-P; W group), the TGF b3 promoter luciferase reporter plasmid with CRE mutation (PGL3-basic-TGF b3P-mCRE; M group) and the renilla luciferase control plasmid (pRL-SV40; control group). TGF b3 promoter activity was assessed by luciferase reporter assays. RESULTS: Compared to N(-), the TGF b3 mRNA expression was reduced to 0.69+/-0.15 in S(-) (P less than 0.05) and increased to 4.68+/-2.76 in C(-) (P more than 0.05). Compared to B(-), the TGF b3 mRNA expression was reduced to 0.57+/-0.08 in H(-) (P less than 0.05). The differences between N(+) and N(-), S(+) and S(-), B(+) and B(-), and H(+) and H(-) were all significant (P less than 0.05). The values of TGF b3 promoter activity in S(W), N(W), and C(W) were 0.062+/-0.013, 0.122+/-0.011, and 0.165+/-0.016 (P less than 0.05), but the changes of TGF b3 promoter activity in S(M), N(M), and C(M) were not significant (P more than 0.05). The values of TGF b3 promoter activity in H(W), B(W), and F(W) were 0.154+/-0.010, 0.188+/-0.016, and 0.276+/-0.031 (P less than 0.05), but the changes of TGF b3 promoter activity in H(M), B(M), and F(M) were not significant (P more than 0.05). CONCLUSION: Increased levels of CREB-1 mRNA or p-CREB-1 up-regulate the TGF b3 mRNA expression and promoter activity in rat HSCs. The CRE site in the TGF b3 promoter is critical for this effect, and the gene's activity becomes significantly decreased when the site is missing. Exogenous TGF b3 enhances expression of endogenous TGF b3 in rat HSCs.


Asunto(s)
Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Células Estrelladas Hepáticas/metabolismo , Regiones Promotoras Genéticas , Factor de Crecimiento Transformador beta3/genética , Animales , Células Cultivadas , ARN Mensajero/genética , Ratas
5.
J Cell Biochem ; 112(4): 1046-54, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21308733

RESUMEN

Previous studies have demonstrated that transforming growth factor-ß3 (TGF-ß3) protected liver against fibrosis in vivo and vitro, but its regulation is poorly understood. In addition, the cAMP-responsive element (CRE) in TGF-ß3 promoter is recognized as an important regulatory site for TGF-ß3 auto-regulation. Thus, we hypothesize that transcription factor CRE-binding protein-1 (CREB-1) regulates the auto-induction of TGF-ß3 in hepatic stellate cells (HSCs). We used exogenous TGF-ß3 to activate the signal pathway of TGF-ß3 auto-regulation in HSCs, results indicated that exogenous TGF-ß3 could up-regulate the protein and mRNA expressions of TGF-ß3, and provoke the phosphorylation of CREB-1 on Ser-133, besides, it could induce the DNA binding activity of p-CREB-1 and activate TGF-ß3 promoter as well. Additionally, we used pGenesil-1.1-shRNA-CREB-1 and pRSV-CREB-1 expression vector to silence and up-regulate CREB-1 gene expression respectively, and the results indicated that inhibition of CREB-1 suppressed exogenous TGF-ß3 stimulation of TGF-ß3 mRNA and protein expressions in HSCs, whereas up-regulation of CREB-1 induced this stimulation. Our results indicate that exogenous TGF-ß3 up-regulates the activity of TGF-ß3 promoter by activating CREB-1, then induces the mRNA and protein expressions of TGF-ß3. Especially, p-CREB-1 is a critical transcription factor in mediating TGF-ß3 auto-induction.


Asunto(s)
Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Células Estrelladas Hepáticas/efectos de los fármacos , Factor de Crecimiento Transformador beta3/farmacología , Animales , Western Blotting , Línea Celular , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Relación Dosis-Respuesta a Droga , Células Estrelladas Hepáticas/metabolismo , Humanos , Modelos Genéticos , Regiones Promotoras Genéticas/genética , Interferencia de ARN , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Crecimiento Transformador beta3/genética , Factor de Crecimiento Transformador beta3/metabolismo
6.
Zhonghua Yi Xue Za Zhi ; 91(33): 2366-9, 2011 Sep 06.
Artículo en Zh | MEDLINE | ID: mdl-22321755

RESUMEN

OBJECTIVE: To explore the effects of exogenous transforming growth factor-ß3 (TGF-ß3) on the activities of its promoter and cAMP-responsive element binding protein-1 (CREB-1) in rat hepatic stellate cell (HSC-T6). METHODS: HSC-T6 was cultured and treated with or without exogenous TGF-ß3 (10 µg/L). Then cell extracts, total RNA and nuclear proteins were collected at different time points. The specimens were detected by luciferase reporter assay, Western blotting and real-time RT-PCR (reverse transcription-polymerase chain reaction) respectively. RESULTS: After treatment, the activity of TGF-ß3 promoter peaked at 24 h (10.68 ± 0.57 vs 4.83 ± 0.56, 2.2 folds vs control). And the mutational CRE site completely blocked the activity of TGF-ß3 promoter (0.73 ± 0.03, P < 0.05). In addition, exogenous TGF-ß3 increased the expression of phospho-CREB-1 in a time-dependent manner. It peaked at 1 h (2.0 folds vs control) and declined slowly. And exogenous TGF-ß3 had no effect on the mRNA and protein expressions of CREB-1 (P > 0.05). CONCLUSION: The activity of TGF-ß3 promoter is up-regulated by exogenous TGF-ß3. And CRE site in TGF-ß3 promoter region is important for the transcription of TGF-ß3 gene in HSC-T6. While activating CREB-1, exogenous TGF-ß3 has no effect on the expressions of CREB-1 protein and mRNA.


Asunto(s)
Células Estrelladas Hepáticas , Factor de Crecimiento Transformador beta3 , Animales , Células Estrelladas Hepáticas/efectos de los fármacos , Regiones Promotoras Genéticas , ARN Mensajero/genética , Ratas , Factor de Crecimiento Transformador beta/metabolismo , Factores de Crecimiento Transformadores
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