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1.
Nanoscale Res Lett ; 16(1): 72, 2021 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-33914179

RESUMEN

A pressing need in low energy spintronics is two-dimensional (2D) ferromagnets with Curie temperature above the liquid-nitrogen temperature (77 K), and sizeable magnetic anisotropy. We studied Mn3Br8 monolayer which is obtained via inducing Mn vacancy at 1/4 population in MnBr2 monolayer. Such defective configuration is designed to change the coordination structure of the Mn-d5 and achieve ferromagnetism with sizeable magnetic anisotropy energy (MAE). Our calculations show that Mn3Br8 monolayer is a ferromagnetic (FM) half-metal with Curie temperature of 130 K, large MAE of - 2.33 meV per formula unit, and atomic magnetic moment of 13/3µB for the Mn atom. Additionally, Mn3Br8 monolayer maintains to be FM under small biaxial strain, whose Curie temperature under 5% compressive strain is 160 K. Additionally, both biaxial strain and carrier doping make the MAE increases, which mainly contributed by the magneto-crystalline anisotropy energy (MCE). Our designed defective structure of MnBr2 monolayer provides a simple but effective way to achieve ferromagnetism with large MAE in 2D materials.

2.
Zhonghua Xin Xue Guan Bing Za Zhi ; 48(9): 721-727, 2020 Sep 24.
Artículo en Chino | MEDLINE | ID: mdl-32957753

RESUMEN

Objective: To investigate the impact of history of hypertension and blood pressure levels on the thromboembolism risk in the setting of nonvalvular atrial fibrillation (NVAF). Methods: China Atrial Fibrillation Registry Study prospectively enrolled 25 512 atrial fibrillation (AF) patients between August 2011 and December 2018. After exclusion of patients with valvular AF, hypertrophic cardiomyopathy, receiving anticoagulation or ablation therapy at the enrollment, 7 757 patients were included in analysis. The primary endpoint was the time to the first occurrence of ischemic stroke or systemic embolism. Cox proportional hazards models were performed to evaluate whether a history of hypertension or blood pressure levels were independently associated with thromboembolism. Results: During a mean follow up of (35±25) months, 455 (5.9%)thromboembolic events occurred. The crude incidence rate of thromboembolism in patients with a history of hypertension was higher than that in patients without hypertension (2.38 vs. 1.35 per 100 patient-years, χ²=16.8,Log-rank P<0.001). Patients were further divided into 4 groups according to systolic blood pressure (SBP) levels at baseline, the crude incidence rate of thromboembolism significantly increased in proportion to the elevation of SBP levels (χ²=17.9,Log-rank P<0.001). However, there was no significant difference in thromboembolism risk among 4 groups stratified by diastolic blood pressure (DBP) levels (χ²=0.6,Log-rank P=0.907). Multivariable regression analysis showed that history of hypertension was independently associated with a 27% higher risk of thromboembolism (HR=1.27, 95%CI 1.01-1.61, P=0.045). Patients with SBP≥140 mmHg (1 mmHg=0.133 kPa) was associated with 36% higher risk of thromboembolism than patients with SBP<120 mmHg (HR=1.36, 95%CI 1.02-1.82, P=0.036). However, patients with SBP 120-129 mmHg or 130-139 mmHg were not at a higher risk of thromboembolism as compared to the patients with SBP<120 mmHg (SBP 120-129 mmHg: HR=1.23, 95%CI 0.90-1.67, P=0.193; SBP 130-139 mmHg: HR=1.30, 95%CI 0.95-1.77, P=0.098). In addition, DBP levels were not independently associated with the increased thromboembolism risk. Conclusion: A history of hypertension and SBP≥140 mmHg are independent predictors of thromboembolism risk in patients with NVAF. These results indicate that intensive efforts to lower SBP below 140 mmHg might be an important strategy to reduce the risk of stroke in patients with NVAF.


Asunto(s)
Fibrilación Atrial , Hipertensión , Accidente Cerebrovascular , Tromboembolia , Presión Sanguínea , China , Humanos , Factores de Riesgo
3.
Eur Rev Med Pharmacol Sci ; 24(9): 4697-4709, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32432733

RESUMEN

OBJECTIVE: Studies have demonstrated that long non-coding RNAs (lncRNAs) are important in the development and prognosis of prostate cancer. The aim of this study was to investigate the functions and mechanism of lnc-SNHG14 in prostate cancer. PATIENTS AND METHODS: Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) or Western blot (WB) were performed to detect mRNA expressions of SNHG14 and miR-5590-3p, and the protein levels of Yin Yang-1 (YY1) in prostate cancer tissues, adjacent tissues, and cancer cell lines. The correlation analysis was used to analyze the correlations between SNHG14, miR-5590-3p, and YY1. Kaplan-Meier survival analysis was used to analyze the overall survival for prostate cancer patients. Cell Counting Kit-8 (CCK-8) assay was performed to measure cell proliferation ability and flow cytometry assay was used to detect cell apoptotic rate. Besides, transwell assay was used to measure cell invasion ability. In addition, WB was performed to measure protein expressions in prostate cancer cell lines. Finally, Luciferase reporter assay was performed to verify the binding sites between SNHG14 and miR-5590-3p, miR-5590-3p, and YY1. RESULTS: The results showed that SNHG14 was significantly increased in prostate cancer tissues and prostate cancer cell lines, which were related with advanced stage and poor diagnosis for prostate cancer patients. MiR-5590-3p was reduced in prostate cancer tissues and cell lines, which were negatively correlated with SNHG14. YY1 was found to be increased in prostate cancer tissues, which was negatively correlated with miR-5590-3p and positively correlated with SNHG14. Furthermore, SNHG14 knockdown inhibited cell proliferation, invasion, and promoted cell apoptosis in DU145 cells. In addition, protein expressions of Cyclin D1, Bcl-2, and N-cadherin were repressed, and the levels of Bax, Cleaved Caspase-3, and E-cadherin were increased. Besides, miR-5590-3p inhibition promoted cell proliferation and invasion, and inhibited apoptosis in DU145 cells. Importantly, Luciferase reporter assay proved that SNHG14 could directly sponge with miR-5590-3p, which could bind with YY1 and regulate the functions of cancer cell. Finally, we proved that SNHG14 regulated cell proliferation, cell apoptosis, and invasion via miR-5590-3p/ YY1 axis in prostate cancer. CONCLUSIONS: Above all, we found that SNHG14 was increased in prostate cancer patients, which was related with future diagnosis for prostate cancer patients. Of note, we discovered that SNHG14 could promote cell proliferation, invasion, and repress cell apoptosis via miR-5590-3p/YY1 axis in prostate cancer, which might provide a new target for treating prostate cancer.


Asunto(s)
Movimiento Celular/fisiología , MicroARNs/metabolismo , Neoplasias de la Próstata/metabolismo , ARN Largo no Codificante/biosíntesis , Factor de Transcripción YY1/metabolismo , Anciano , Proliferación Celular , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/patología
4.
Nanoscale ; 12(21): 11627-11637, 2020 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-32436494

RESUMEN

Two-dimensional (2D) magnets with room temperature ferromagnetism and semiconductors with moderate band gap and high carrier mobility are highly desired for applications in nanoscale electronics and spintronics. By performing the first-principles calculations, we investigate novel Fe, Co, Ni carbide based pristine (M2C) and functionalized (M2CT2, T: F, O, OH) MXenes. Our calculations show that Fe2C, Co2C, Ni2C, Fe2CF2, Fe2CO2, Fe2C(OH)2, Co2CF2, Co2C(OH)2 and Ni2CF2 are dynamically and mechanically stable. More importantly, Fe2C, Co2C, Fe2CF2 and Fe2C(OH)2 exhibit intrinsic ferromagnetism (magnetic moments 2-5µB per unit cell). Monte Carlo simulations suggest high Curie temperatures of 590 and 920 K for Fe2C and Fe2CF2, respectively, at the HSE06 level owing to the large spin magnetic moments and strong ferromagnetic coupling. Based on the deformation potential theory, we predict high and anisotropic hole mobility (0.2-1.4 × 104 cm2 V-1 s-1) for semiconducting Fe2CO2 and Co2C(OH)2. Additionally, Ni2CF2 demonstrates highly anisotropic electron mobility together with a direct band gap. Our results further show the effectiveness of surface functionalization in modulating the electronic and magnetic properties and broadening the properties of MXenes to achieve long-range intrinsic ferromagnetism well above room temperature and high carrier mobility.

5.
Zhonghua Xin Xue Guan Bing Za Zhi ; 48(3): 223-227, 2020 Mar 24.
Artículo en Chino | MEDLINE | ID: mdl-32234180

RESUMEN

Objective: To investigate the relationship between high sensitivity C-reactive protein (hs-CRP) level and incidence of left atrial spontaneous echocardiographic contrast (LASEC) in the patients with nonvalvular atrial fibrillation (AF). Methods: Four hundred and ninety consecutive patients with nonvalvular atrial fibrillation who underwent radiofrequency ablation for the first time from January 1, 2018 to June 30, 2018 in the Department of Cardiology, Beijing Anzhen Hospital were enrolled. According to the results of transesophageal echocardiography before radiofrequency ablation, patients were divided into the group without LASEC (n=338) and the group with LASEC (n=152). hs-CRP was determined by latex enhanced immunoturbidimetry. The relationship between hs-CRP and LASEC in patients with nonvalvular atrial fibrillation was investigated by univariate and multivariate logistic analysis. Results: LASEC was detected in 152 (31%) of 490 patients. Significant differences in age, type of atrial fibrillation, previous embolic events, fibrinogen, D-dimer, the left atrial anteroposterior diameter and CHA(2)DS(2)-VASc scores were found between patients with and without LASEC (all P<0.05). Compared with the group without LASEC, the serum hs-CRP level was significantly higher in the group with LASEC (3.16 (1.30, 5.23) mg/L vs. 0.67 (0.37, 1.48) mg/L, P<0.001). Multivariate logistic regression analysis showed that hs-CRP (OR=1.136, 95%CI 1.060 - 1.217, P<0.001) and D-dimer (OR=1.040, 95%CI 1.011 - 1.070, P=0.007) were independent determinants for LASEC in this patient cohort. Conclusions: hs-CRP is an independent determinant for LASEC in patients with nonvalvular atrial fibrillation. Inflammation may thus be involved in the formation of prethrombotic state in patients with nonvalvular atrial fibrillation.


Asunto(s)
Fibrilación Atrial , Apéndice Atrial , Fibrilación Atrial/epidemiología , Proteína C-Reactiva , Ecocardiografía Transesofágica , Electrocardiografía , Atrios Cardíacos , Humanos , Incidencia , Factores de Riesgo
6.
J Anim Sci ; 89(8): 2356-64, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21421836

RESUMEN

Sorbic acid (SA) is a PUFA with a conjugated double bond. The conjugated fatty acids, including CLA, are multifunctional bioactive fatty acids with the ability to improve growth performance. The effect of SA on pig growth performance was examined to determine its mechanism of action. The ADG, ADFI, and serum IGF-I concentration were examined, as were IGF-I secretion and IGF system gene expression in hepatocytes. Two hundred forty 21-d-old Duroc × Landrace × Yorkshire weaned piglets (6.86 ± 0.02 kg) were randomly divided into 4 groups, each consisting of 3 pens of 20 piglets (10 female and 10 male). The 4 groups of piglets were kept in a temperature-controlled room (26 to 28 °C), and feed and water were provided to the pigs ad libitum. Weanling piglets were fed diets that included 0, 0.5, 2, or 4 g of SA/kg for 42 d. The diet supplemented with 0.5 g/kg of SA improved (P < 0.05) ADG, BW, and G:F, whereas supplementation with all 3 SA doses increased (P < 0.05) ADG and G:F at 21 to 42 d of age. The greatest concentration of plasma triglycerides was observed (P < 0.05) in the 4 g/kg of SA group. The SA increased (0.5 g of SA/kg, P > 0.05; 1 g of SA/kg, P < 0.05; and 2 g of SA/kg, P < 0.05, respectively) plasma total serum protein and globulin concentrations in a dose-dependent manner. It was noted that the smallest SA treatment dose (0.5 g/kg) dramatically increased (P < 0.05) serum IGF-I concentration but decreased (P < 0.05) the concentrations of blood urea N and cortisol. The SA increased (P < 0.05) IGF-I, IGF-II, IGF-I receptor (IGF-IR), and PPARα gene mRNA expression and IGF-I secretion, but not (P > 0.05) IGFBP or PPARγ mRNA expression, in pig primary hepatocytes. These results indicate that SA improves growth performance by regulating IGF system gene expression and hormone secretion.


Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Ácido Sórbico/farmacología , Porcinos/crecimiento & desarrollo , Porcinos/metabolismo , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Suplementos Dietéticos , Femenino , Hormona del Crecimiento/genética , Hormona del Crecimiento/metabolismo , Factor I del Crecimiento Similar a la Insulina/genética , Masculino , PPAR alfa/genética , PPAR alfa/metabolismo , PPAR gamma/genética , PPAR gamma/metabolismo
7.
Appl Opt ; 50(3): 387-91, 2011 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-21263739

RESUMEN

In this work we have replaced a commonly used Au film with an Au/Ag bimetallic film working as the sensing chip in the commercial surface plasmon resonance (SPR) instrument, Biacore 3000. The bimetallic chip gives out sharper SPR dip than that by the chip made of an Au film. The applicability and stability of the bimetallic chip on the Biacore 3000 are tested by real-time monitoring of biological coupling processes between sulfamethoxazole (SMX) and anti-SMX, which is useful in rapid detection of contaminations in food products. The bimetallic chip performs stably in 6 times' usage and regeneration. Our experiment is helpful to push the bimetallic film into real applications in commercial SPR instruments.


Asunto(s)
Análisis de los Alimentos/instrumentación , Contaminación de Alimentos/análisis , Resonancia por Plasmón de Superficie/instrumentación , Técnicas Biosensibles/instrumentación , Oro/química , Plata/química , Sulfametoxazol/química
8.
World J Gastroenterol ; 7(6): 868-71, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11854919

RESUMEN

AIM: To study preliminarily the properties of myosin light chain kinase (MLCK) in rabbit liver. METHODS: The expression of MLCK was detected by reverse transcription-polymerase chain reaction(RT-PCR); the MLCK was obtained from rabbit liver, and its activity was analyzed by gamma-(32)P incorporation technique to detect the phosphorylation of myosin light chain. RESULTS: MLCK was expressed in rabbit liver, and the activity of the enzyme was similar to rabbit smooth muscle MLCK, and calmodulin-dependent. When the concentration was 0.65 mg x L(-1), the activity was at the highest level. CONCLUSION: MLCK expressed in rabbit liver may catalyze the phosphorylation of myosin light chain, which may play important roles in the regulation of hepatic cell functions.


Asunto(s)
Hígado/enzimología , Cadenas Ligeras de Miosina/metabolismo , Quinasa de Cadena Ligera de Miosina/metabolismo , Animales , Hepatocitos/enzimología , Hígado/citología , Fosforilación , Conejos
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