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1.
Entropy (Basel) ; 26(3)2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38539711

RESUMEN

This paper concerns a class of coupled competitive neural networks, subject to disturbance and discontinuous activation functions. To realize the fixed-time quasi-bipartite synchronization, an aperiodic intermittent controller is initially designed. Subsequently, by combining the fixed-time stability theory and nonsmooth analysis, several criteria are established to ensure the bipartite synchronization in fixed time. Moreover, synchronization error bounds and settling time estimates are provided. Finally, numerical simulations are presented to verify the main results.

2.
Clin Invest Med ; 42(4): E28-E36, 2019 12 29.
Artículo en Inglés | MEDLINE | ID: mdl-31922706

RESUMEN

PURPOSE: Oxygen therapy is commonly used in clinical settings, but several problems may result from improper use. Oxygen poisoning involves the initiation of a series of inflammatory reactions. In this study, we compared the effects of moderate hyperoxia (40% O2) and extreme hyperoxia (85% O2) on pulmonary bronchial epithelial cells. METHODS: Normal human tracheobronchial epithelium (NHBE) cells were exposed to hyperoxia (40% and 85%) for 24 hours, and their survival rates were determined by the colorimetic assay, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide). The protein and mRNA levels of RelA, RelB, ASK1, TNF-α and secretory component (SC) were detected by immunohistochemical staining, western blot, and real-time polymerase chain reaction. RESULTS: The NHBE cell survival increased in the presence of moderate hyperoxia. RelA, RelB, ASK1, TNF-α and SC expressions were significantly higher in the 85% O2 group in comparison with the control group and the 40% O2 group. In the 40% O2 group, RelA, RelB, ASK1 and TNF-α were upregulated, but SC expression was not significantly different than that of the control group. However, compared with the 85% O2 group, SC expression was significantly lower in the 40% O2 group. CONCLUSION: These results suggest that moderate hyperoxia promotes proliferation in NHBE cells and activates TNF-α and downstream ASK1. Then TNF-α activates NF-κB and SC to play a protective role.


Asunto(s)
Células Epiteliales/metabolismo , Hiperoxia/metabolismo , Línea Celular , Supervivencia Celular/genética , Supervivencia Celular/fisiología , Humanos , Inmunohistoquímica , MAP Quinasa Quinasa Quinasa 5/genética , MAP Quinasa Quinasa Quinasa 5/metabolismo , FN-kappa B/metabolismo , ARN Mensajero/metabolismo , Factor de Transcripción ReIA/genética , Factor de Transcripción ReIA/metabolismo , Factor de Transcripción ReIB/genética , Factor de Transcripción ReIB/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
3.
J Colloid Interface Sci ; 629(Pt B): 598-609, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36179579

RESUMEN

For photoelectrochemical (PEC) water splitting, constructing heterojunctions and loading co-catalysts are effective means to realizing sufficient light absorption, effective photogenerated carrier separation and fast charge transport. However, during implementation, the PEC performance of the catalyst is affected by both parasitic light absorption and reflection and the change in energy band structure due to the creation of new interfaces. Herein, in order to minimize the effect of recombination of photogenerated electron-hole pairs on the catalyst PEC performance due to the nascent interface arising from the co-catalyst compounding, WO3 and Ni/Co co-doped LaFeO3 (LFO) are constructed as heterojunctions, in which NiCo-LFO acts both as a part of the heterojunction to enhance photogenerated carrier separation and a co-catalyst to enhance the conductivity and modulate the surface state density at the catalyst-electrolyte interface. The current density of NiCo-LFO/WO3 reaches 3.92 mA cm-2, which is more than 7 times that of LFO/WO3. This work provides a reference for the efficient water splitting of B-site doped, especially the co-doped perovskite oxide as multifunctional roles integrated with conventional photoelectrodes.

4.
Front Nutr ; 8: 751627, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34631776

RESUMEN

The extent of retrogradation strongly affects certain physical and cooking properties of rice starch (RS), which are important to consumers. In this study, oligomeric procyanidins from lotus seedpod (LSOPC) was prepared and used to investigate its inhibitory effect on RS retrogradation. Various structural changes of RS during retrogradation were characterized by differential scanning calorimetry, low field nuclear magnetic resonance, X-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy. The results showed LSOPC could effectively retard both short- and long-term retrogradation of RS, and its inhibitory effect was dependent on the administered concentration of LSOPC. Molecule simulation revealed the interactions of RS and LSOPC, which indicated that the competition of hydrogen bonds between RS and LSOPC was the critical factor for anti-retrogradation. This inhibitory effect and mechanism of action of LSOPC could promote its applications in the field of starch anti-retrogradation.

5.
Food Funct ; 11(6): 5396-5408, 2020 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-32469349

RESUMEN

Advanced glycation end products (AGEs) and their important intermediate products (α-dicarbonyl compounds) that are generated by the Maillard reaction are closely related to diabetes. Our study first investigated the mechanisms of the anti-glycation effects of epicatechin (EC), (-)-epicatechin gallate (ECG), (-)-epigallocatechin (EGC), and (-)-epigallocatechin gallate (EGCG) in an alcoholic environment. The results showed that catechins played an important role in the inhibition of AGE formation, and the effect of EC was the best. Their corresponding mechanisms included total antioxidant capacity (TAOC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging ability, trapping of methylglyoxal (MGO), protection of the protein structure, and inhibition of the activities of α-amylase, α-glucosidase, and ß-glucosidase, which were consistent with the study of molecular docking. This study will offer a theoretical basis for the applications of different types of catechins to alcoholic beverages as natural AGE formation inhibitors.


Asunto(s)
Catequina/química , Catequina/metabolismo , Productos Finales de Glicación Avanzada/química , Productos Finales de Glicación Avanzada/metabolismo , Antioxidantes/farmacología , Sitios de Unión/efectos de los fármacos , Compuestos de Bifenilo , Catequina/análogos & derivados , Catequina/farmacología , Glucosidasas/efectos de los fármacos , Glicosilación , Simulación del Acoplamiento Molecular , Picratos , Piruvaldehído , alfa-Amilasas/efectos de los fármacos , alfa-Glucosidasas/metabolismo
6.
Food Chem ; 272: 679-687, 2019 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-30309598

RESUMEN

Nonenzymatic glycosylation (NEG) can generate advanced glycation end products (AGEs) and its intermediates α-dicarbonyl compounds, which contribute to the risk of diabetes. This study investigated the anti-glycation mechanisms and structure-activity relationship of (+)-catechin (CC) and (-)-epicatechin (EC). The results showed that the effect of CC on inhibiting AGEs was significantly better than that of EC (p < 0.05). By exploring the mechanism, we found that there was no significant difference in the ability of CC and EC to capture α-dicarbonyl compounds. But CC was found to be more efficient than EC to inhibit RO, OH and CHO radicals generation, which may be the primary reason that CC was more effective than EC on AGEs inhibition. What's more, CC showed better inhibitory effect on ß-glucosidase that was close to the molecular docking study. Our results will provide a theoretical foundation for development of different structure of procyanidins as natural AGEs inhibitors in food and medicine.


Asunto(s)
Biflavonoides/química , Catequina/química , Productos Finales de Glicación Avanzada/química , Proantocianidinas/química , Biflavonoides/metabolismo , Sitios de Unión , Catequina/metabolismo , Cromatografía Líquida de Alta Presión , Productos Finales de Glicación Avanzada/metabolismo , Glioxal/química , Humanos , Simulación del Acoplamiento Molecular , Proantocianidinas/metabolismo , Estructura Terciaria de Proteína , Relación Estructura-Actividad , Espectrometría de Masas en Tándem , alfa-Amilasas/antagonistas & inhibidores , alfa-Amilasas/metabolismo , beta-Glucosidasa/antagonistas & inhibidores , beta-Glucosidasa/metabolismo
7.
Int J Mol Med ; 41(1): 322-330, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29138796

RESUMEN

Long-term therapeutic hyperoxia may exert serious toxic effects on intestinal epithelial cells in vitro and in vivo. The aim of the present study was to investigate the cause of this intestinal injury under conditions of hyperoxia. Caco-2 cells were treated with different concentrations of hydrogen peroxide (H2O2) and 85% hyperoxia for 24 h. higher rates of injury of Caco-2 cells were observed in the hyperoxia and H2O2 groups compared with the control group. The reactive oxygen species (ROS) level of the hyperoxia group was significantly higher compared with that of the 400 µM H2O2 group. The protein and gene levels of RelA, RelB, hypoxia­inducible factor-1α, tumor necrosis factor-α and apoptosis signal­regulating kinase 1 were significantly higher in the hyperoxia and H2O2 groups compared with those in the control group. In conclusion, during hyperoxia, intestinal epithelial cells were destroyed and the levels of ROS were increased. Therefore, ROS may play an important role in intestinal injury in a hyperoxic environment.


Asunto(s)
Hiperoxia/fisiopatología , Mucosa Intestinal/metabolismo , Necrosis/patología , Especies Reactivas de Oxígeno/toxicidad , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Células CACO-2 , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/patología , Regulación de la Expresión Génica/genética , Humanos , Peróxido de Hidrógeno/toxicidad , Hiperoxia/inducido químicamente , Hiperoxia/genética , Hiperoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Mucosa Intestinal/lesiones , Mucosa Intestinal/patología , MAP Quinasa Quinasa Quinasa 5/genética , FN-kappa B/genética , Necrosis/inducido químicamente , Necrosis/metabolismo , Oxígeno/metabolismo , Oxígeno/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Factor de Necrosis Tumoral alfa/genética
8.
China Tropical Medicine ; (12): 906-2023.
Artículo en Zh | WPRIM | ID: wpr-1016365

RESUMEN

@#Abstract: Objective To evaluate the application of TB laboratory detection technology in Liaoning Province from 2016 to 2022, and to provide scientific basis for further improving the detection rate of Mycobacterium tuberculosis in the province. Methods The medical records of registered tuberculosis patients in Liaoning Province from 2016 to 2022 were collected from the "Tuberculosis Information Management System" in the "China Disease Prevention and Control Information System" subsystem. Statistical analysis was performed for sputum coating, sputum culture, and molecular biology testing. Results From 2016 to 2022, a total of 152 778 patients with pulmonary tuberculosis were registered in Liaoning Province. The detection rate of sputum smear microscopy was 98.03% (149 775/152 778), the detection rate of sputum culture was 20.72% (31 661/152 778), and the detection rate of molecular biology testing was 20.21% (30 737/152 778). From 2018 to 2022, the rate of molecular biological detection showed an increasing trend (χ2trend=7 104.466, P<0.01), while from 2016 to 2021, the detection rate of sputum culture showed an increasing trend, with statistical significance (χ2trend=3,068.701, P<0.01). The sputum smear detection rate showed a downward trend(χ2trend=689.913, P<0.01). . There were significant differences in the results of sputum smear microscopy, sputum culture, and molecular biology testing, as confirmed by the McNemar test (P<0.01). The positive rate of pathogenic academics increased from 26.27% in 2016 to 51.55% in 2022, showing a yearly upward trend (χ2trend=5 262.863, P<0.01), with significant differences between each year (χ2=5 686.935, P<0.01). Among pulmonary tuberculosis patients with positive pathogenic microorganisms, the proportion of sputum smear-positive cases decreased from 94.32% to 52.36%, showing a downward trend (χ2trend=5 010.104, P<0.01). The proportion of culture-positive cases increased from 5.68% in 2016 to 12.83% in 2022, showing an upward trend (χ2trend=122.501, P<0.01). In Liaoning Province, molecular biology testing has been carried out since 2018, and the proportion of molecular biology-positive cases increased from 11.51% to 34.81%, showing an increasing trend (χ2trend=1 969.326, P<0.01). The number of positive patients in molecular biological tests in municipal hospitals accounted for 18.69% (8 386/44 778) of etiological positive patients, while the number of positive patients in county-level hospitals accounted for 13.61% (2 439/17 924) of etiological positive patients, with significant differences (χ2=231.594, P<0.01). Conclusions The implementation of molecular biology testing for tuberculosis in Liaoning Province is one of the main measures to improve the positive rate of etiology, and it helps to diagnose tuberculosis patients timely and accurately

9.
Exp Ther Med ; 14(5): 4033-4040, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29075338

RESUMEN

Redox imbalance is established in various human diseases. Treatment of intestinal epithelial cells with hyperoxia for a prolonged period of time may cause serious effects on redox balance. Secretory component (SC) protein is secreted by intestinal epithelial cells, and has a vital role in mucosal immune systems and intestinal defense. The present study aimed to investigate the influence of reactive oxygen species (ROS) on intestinal epithelial cells and intestinal epithelial SC protein under hyperoxic conditions. Caco-2 cells were treated with increasing concentrations of hydrogen peroxide (H2O2) or 85% O2 (hyperoxia) for 24 h. Flow cytometry, immunohistochemistry staining, western blot analysis and reverse transcription-quantitative polymerase chain reaction were performed to detect the expression levels of SC protein. Significantly increased apoptosis and mortality rates were observed in hyperoxia- and H2O2-treated Caco-2 cells, as compared with the untreated control cells (P<0.05). Protein and mRNA expression levels of SC were significantly increased in hyperoxia- and H2O2-treated groups, as compared with the control group (P<0.05). During hyperoxia, intestinal epithelial cells were destroyed and ROS levels increased. Therefore, the results of the present study suggested that ROS might have an important role in intestinal injury in hyperoxic environments.

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