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The coupling of efficient adsorption and effective charge separation with photocatalysts enables the use of sunlight for photocatalytic reduction of carbon dioxide (CO2) into high-value-added products. In this work, we used a straightforward solid-phase hydrothermal technique to build an oxygen-vacancy-rich, heterogeneous interface-coupled CeO2/mesoporous TiO2 framework structural system. The heterogeneous structure was constructed by introducing oxygen-vacancy-rich CeO2 into mesoporous TiO2, which may encourage the transfer of charges and increase the number of active sites and CO2 adsorption by utilizing the coupled synergistic effect of oxygen vacancies and heterogeneous interfaces, and it can also regulate the pathway of the photocatalytic reaction and the selectivity of the products. The composite of CeO2 with different morphologies and oxygen-rich vacancies regulated the system's active sites and degree of exposure and enhanced photocatalytic CO2 reduction. The highest CO yield of 6.25 mmol gcat-1 was obtained by use of the rod CeO2/mesoporous TiO2 composite photocatalyst (R-CeO2/TiO2), and this yield was 1.6 times higher than that of pure mesoporous TiO2 and 1.84 times higher than that of pure R-CeO2. Also, the product selectivity increased by 4.3% compared to a single sample. Combining the Mott-Schottky plot results and the energy-barrier perspective to further explore the photocatalytic reduction of the CO2 reaction mechanism as well as the product selectivity, it appears that the construction of the composite system of oxygen-rich vacancies and heterogeneous boundary-coupled photocatalysis provides a practical pathway for the photocatalytic reaction, which may contribute to the photocatalytic reaction's high efficiency and yield selectivity.
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Aim: Lysosomal pH changes are associated with drug resistance, cell growth and invasion of tumors, but effective and specific real-time monitoring of lysosomal pH compounds for cancer therapy is lacking. Materials & methods: Here, based on the covalent linkage of the anticancer drug palbociclib and fluorescent dye fluorescein isothiocyanate (FITC), we designed and developed a novel palbociclib-derived multifunctional molecule (Pal-FITC) for lysosomal targeting and diagnostic therapeutic integration. Results & discussion: Pal-FITC fluoresces is 20-fold stronger than that of FITC and shows a linear response in the pH range of 4.0-8.2 (R2 = 0.9901). Pal-FITC blocks cells in G1 phase via Cyclin D-CDK4/6-Rb. Conclusion: Our study provides new strategies for tumor-targeted imaging and personalized therapy.
Based on the covalent linkage of the anticancer drug and the fluorescent dye, we designed and developed a novel palbociclib-derived multifunctional molecule (Pal-FITC) for lysosomal targeting and diagnostic therapeutic integration. Pal-FITC responded linearly in the pH range of 4.08.2. In addition, Pal-FITC was able to effectively treat lung cancer without toxic side effects on normal cells. It has a significant cell cycle blocking phenomenon and blocks G1 phase cells via Cyclin D-CDK4/6-Rb. Our study provides a new strategy for tumor-targeted imaging and personalized therapy.
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Antineoplásicos , Lisosomas , Piperazinas , Piridinas , Humanos , Piridinas/química , Piridinas/farmacología , Lisosomas/metabolismo , Piperazinas/química , Piperazinas/farmacología , Antineoplásicos/farmacología , Antineoplásicos/química , Colorantes Fluorescentes/química , Colorantes Fluorescentes/farmacología , Colorantes Fluorescentes/síntesis química , Fluoresceína-5-Isotiocianato/química , Proliferación Celular/efectos de los fármacos , Concentración de Iones de Hidrógeno , Línea Celular Tumoral , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 4 Dependiente de la Ciclina/metabolismo , Estructura MolecularRESUMEN
In this study, an ab initio molecular dynamics method is employed to investigate how the microstructures of UO2 and U3Si evolve under electron excitation. It is found that the U3Si is more resistant to electron excitation than UO2 at room temperature. UO2 undergoes a crystalline-to-amorphous structural transition with an electronic excitation concentration of 3.6%, whereas U3Si maintains a crystalline structure until an electronic excitation concentration reaches up to 6%. Such discrepancy is mainly due to their different electronic structures. For insulator UO2, once valence U 5f electrons receive enough energy, they are excited to the conduction bands, which induces charge redistribution. Anion disordering is then driven by cation disordering, eventually resulting in structural amorphization. As for metallic U3Si, the U 5f electrons are relatively more difficult to excite, and the electron excitation leads to cation disordering, which eventually drives the crystalline-to-amorphous phase transition. This study reveals that U3Si is more resistant to electron excitation than UO2 under an irradiation environment, which may advance the understanding of related experimental and theoretical investigations to design radiation-resistant nuclear fuel uranium materials.
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Objective: Based on the theory of Job Demands-Resources, this study has been set out to examine how parenting demands, parenting resources affect parental burnout of primary school students' parents. Methods: An online survey with four scales (Parenting Stress Scale, Perceived Family Support Scale, Psychological Resilience Scale and Parental Burnout Scale) was completed by 600 parents of students from three primary schools in Central China. Structural equation models were implemented. Results: Parenting stress had a positive impact on parental burnout (ß = 0.486, p < 0.001). Both perceived family support (ß = -0.228, p < 0.001) and psychological resilience (ß = -0.332, p = 0.001) had a negative impact on parental burnout. Perceived family support played a moderating role between parenting stress and parental burnout (ß = -0.121, p < 0.001). Psychological resilience also played a moderating role between parenting stress and parental burnout (ß = -0.201, p < 0.001). Psychological resilience partially mediated the relationship between perceived family support and parental burnout. The total effect was -0.290, with 95% CI (-0.350, -0.234). Direct effect was -0.228, with 95% CI (-0.283, -0.174), and indirect effect was -0.062, with 95% CI (-0.092, -0.037). Conclusion: Parental burnout may be reduced by increasing family support and self-improvement of psychological resilience. In the same way, the impact of parenting stress on parental burnout may be buffered under high-pressure situations.
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BACKGROUND: There is not a general agreement regarding antiarrhythmic effects on atrial fibrillation (AF) of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs). This study was to assess whether ACEIs and ARBs could decrease the incidence of AF. MATERIALS AND METHODS: Medline, Embase and Cochrane Library databases were searched for trials reported from 1950 to May 2009. Search terms included 'randomized controlled trial (RCT), controlled clinical trials, random allocation' and medical subject headings that included all spellings of ACEIs and ARBs agents, 'atrial fibrillation' and 'atrial flutter'. Randomized, controlled human trials of ACEIs or ARBs reporting AF were included. Data were extracted independently by two reviewers using a predefined data extraction sheet, including study quality indicators. Meta-analysis and subgroup analyses were carried out with a random effects model. RESULTS: Twenty-one trials including 91,381 patients and 5730 AF events were identified. Overall, ACEIs/ARBs reduced the relative risk (c) of AF by 25%. In primary and secondary prevention, ACEIs/ARBs decreased the incidence of AF by 24% and 27%, respectively. Patients with hypertension (RR: 0·71, 95%CI: 0·54-0·92), patients with chronic heart failure (RR: 0·58, 95%CI: 0·39-0·87) and those with AF (RR: 0·71, 95%CI: 0·52-0·96) benefited from ACEIs/ARBs treatment. CONCLUSIONS: ACEIs/ARBs are effective for primary prevention and secondary prevention of AF. They decrease the incidence of AF especially in patients with hypertension, patients with chronic heart failure and those with AF.
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Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Antiarrítmicos/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Anciano , Fibrilación Atrial/prevención & control , Humanos , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Resultado del TratamientoRESUMEN
The rational design and controlled construction of active centers remain grand challenges in heterogeneous catalysis, in particular for oxide catalysts with complex surface and interface structures. This work describes a facile way in the design of highly active Ni-O Lewis pairs for water activation where Ni and O sites act as Lewis acid and base, respectively. Surface science experiments indicate that dissociative adsorption of water occurs at edges of NiOx nanoislands grown on Au(111) and NiOx-Ni interfaces formed by further depositing metallic Ni layers along the edges of NiOx nanoislands. Enhanced activity of Ni-O Lewis pairs at the NiOx-Ni interface has been demonstrated by theoretical calculations, which are attributed to the higher Lewis acidity of metallic Ni sites and synergy of the metal and oxide components. Moreover, proton can migrate away from the NiOx-Ni interface and refresh the O base sites, leading to further hydroxylation of the neighboring Ni acid sites.
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OBJECTIVE: To explore the epidemiological status of abnormal glucose metabolism and its influential factors among middle and aged population with hypertension in Chengdu area. METHODS: In 2008, after adopting the methods of stratified cluster sampling, the authors investigated 4685 subjects of the middle and aged population between the age of 40 - 79 in Chengdu urban and rural area by checking blood pressure and oral glucose tolerance test (OGTT). Patients with previously known diabetes mellitus (DM) were only asked to perform fasting glucose and to carry out a questionnaire. Comparison of the prevalence rates of abnormal glucose metabolism in hypertensive and non-hypertensive subjects was carried out. The prevalence rates of isolated impaired glucose tolerance (I-IGT) and isolated postprandial hyperglycemia (IPH) among middle and aged subjects with hypertension were acquired and the influential factors of abnormal glucose metabolism among middle and aged subjects with hypertension were analyzed. RESULTS: The prevalence rate of abnormal glucose metabolism in the hypertensive subjects was obviously higher than that in the non-hypertensive subjects; without using OGTT, 72.9% of the pre-diabetic and 54.4% of the new diagnosed DM patients would remain undiagnosed if fasting plasma glucose detection was used alone. Age, diabetic history of first degree relatives, overweight or obesity were the risk factors for the development of abnormal glucose metabolism among middle and aged male subjects with hypertension in Chengdu area. Exercise training and high education level were the protective factors. Age, diabetic history of first degree relatives, abdominal obesity and hypertriglyceridemia were the risk factors for the development of abnormal glucose metabolism among middle and aged female subjects with hypertension in Chengdu area. CONCLUSIONS: More than 50% of middle and aged subjects with hypertension in Chengdu area has accompanying abnormal glucose metabolism. OGTT easily discloses the abnormal status and should be a routine procedure in the diagnosis of pre-diabetes or DM in such population. Appropriate exercise, learning diabetes-related knowledge to take reasonable lifestyle, and intervention of metabolic factors such as overweight or obesity are advised. Abdominal obesity and hypertriglyceridemia play important roles in leading to abnormal glucose metabolism among middle and aged population with hypertension.
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Glucemia/metabolismo , Trastornos del Metabolismo de la Glucosa/epidemiología , Hipertensión/metabolismo , Adulto , Anciano , China/epidemiología , Femenino , Intolerancia a la Glucosa , Trastornos del Metabolismo de la Glucosa/metabolismo , Humanos , Hipertensión/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Factores de RiesgoRESUMEN
OBJECTIVE: To develop the evaluation tool for the risk level of abnormal glucose metabolism morbidity in the middle-aged and elder populations. METHODS: By the stratified cluster sampling method, a survey was conducted in middle-aged and elder populations aged 40 - 70 years old in urban and rural areas of Chengdu during April-November 2008. The parameters included blood pressure, fasting blood glucose, blood glucose after oral administration of 75 g glucose, blood lipid, blood uric acid, height, body weight and waistline, etc. A total of 5205 valid copies of questionnaires were obtained. A discriminant analysis and a multifactorial logistic regression analysis were conducted. The quantitative scoring system was established and the ROC analysis conducted to screen the boundary point of the quantitative scoring system. The discriminant performance of simple scoring model was conducted in 336 subjects for physical examination. RESULTS: The accuracies of discriminant analysis in male and female models were 79.04% and 81.35% respectively. The simple male scoring mode included the following eight parameters: age, physical work intensity, parental history of diabetes mellitus, sibling's history of diabetes mellitus, BMI index, existing abdominal obesity and history of hypertension. The simple female scoring mode included the following eight parameters: age, physical work intensity, physical training, parental history of diabetes mellitus, sibling's history of diabetes mellitus, BMI index, existing abdominal obesity, history of hypertension, number of parturition and history of gestational diabetes mellitus. The ROC AUCs were 0.701 and 0.728 in male and female models respectively. During applications in other populations, the sensitivity and specificity of the male model were 86.86% and 65.12% while those of female model 88.89% and 72.97% respectively. CONCLUSIONS: The newly developed evaluation tool for the risk level of abnormal glucose metabolism morbidity in middle-aged and elder populations is both simple and practical. With an excellent practicability; it may be used to screen abnormal glucose metabolism in middle-aged and elder populations.
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Intolerancia a la Glucosa/epidemiología , Trastornos del Metabolismo de la Glucosa/epidemiología , Diseño de Software , Adulto , Anciano , China/epidemiología , Femenino , Intolerancia a la Glucosa/metabolismo , Trastornos del Metabolismo de la Glucosa/metabolismo , Prueba de Tolerancia a la Glucosa , Humanos , Masculino , Persona de Mediana Edad , Medición de RiesgoRESUMEN
The 1% Eu3+ doped Eu3+ /TiO2 nano-powders were prepared via sol-gel method by using Eu(NO3)3 and Eu2 (CA)3 (phen)2 (CA: camphoric acid; phen: 1, 10-phenanthroline) as precursors respectively, and the samples were characterized by thermal analyses (TG-DTA), X-ray powder diffraction(XRD), scanning electron microscope(SEM), Fourier transform infrared spectroscopy (FTIR), UV-Vis absorption spectra and fluorescence spectra for their microstructure, morphology and spectroscopy properties. The results of TG-DTA and XRD indicate that the increasing trend of particle size and the conversion temperature of crystalline phase of the as prepared samples was restrained when using organic complexes Eu2(CA)3 (phen)2 as the do pant. The particle size was decreased from 9 to 7 nm, and the name powders were still anatase TiO2 when the calcination temperature was increased up to 500 degrees C. The absorption peak at about 370 nm in UV-Vis spectra was red-shifted when doping with organic complexes Eu2 (CA)3 (phen)2, namely the doped TiO2 nano powders have the ability of visible light responding. The characteristic absorption peaks of organic complex did not appear in FTIR spectrum, indicating that the Eu3+ has little impact on the formation process of TiO2 crystal when using Eu2(CA)3 (phen)2 as precursor. The result of fluorescence spectrum indicates that the characteristic transition of Eu3+ at 578 nm (corresponding to (5)D0---(7)F0), 590 nm((5)D0-(7)F1) and 612 nm ((5)D0-(7)F2) appeared in both samples, in which the peak at 612 nm was the characteristic red transmutation peak. When doping Eu3+ with the same content, the nano-powders using Eu2 (CA)3 (phen)2 as precursor obtain higher luminescence intensity. Therefore, by using a simple approach, the authors prepared the light-emitting rare earth inorganic nano-powders with better luminescence property and high stability, and such inorganic nano-powders might have potential applications in many fields.
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Photoemission electron microscopy (PEEM) is a powerful surface technique for dynamic imaging of surface processes while PEEM studies have been performed under ultrahigh vacuum or high vacuum conditions. Here we report on a near ambient pressure PEEM (NAP-PEEM) instrument, which enables high resolution PEEM imaging in near ambient pressure (> 1 mbar) gases over a wide temperature range (150 - 1200â¯K). Installed with an electron gun near ambient pressure low energy electron microscopy (NAP-LEEM) can be achieved as well. The success of this new NAP-PEEM/LEEM instrument relies on the following key design concepts. First, a two-stage accelerating electric field consisting of a low field region between sample and intermediate electrode ("nozzle") and a high field between nozzle and objective lens. Second, a three-stage differential pumping system allowing a near ambient pressure atmosphere at the sample surface while ultrahigh vacuum maintained in the imaging lens systems. Third, a unique NAP cell with gas inlet/outlet, light illumination, sample cooling/heating, and precise sample positioning. The new technique will have important applications in surface catalysis, thin film growth, and energy conversion devices under nearly realistic working conditions.
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OBJECTIVE: To evaluate the predictive value of admission plasma B-type natriuretic peptide (BNP) and pulmonary capillary wedge pressure (PCWP) for long term cardiovascular events in patients with chronic heart failure (CHF). METHODS: A total of 134 patients [70 males and 64 females, mean age (71.28 +/- 8.22) years] with CHF were included in this study. PCWP was measured with a Swan-Ganz catheterization and plasma BNP level was determined by a rapid immunofluorescence assay (Triage, Biosite, USA) in all patients on admission day. Left ventricular end diastolic diameter (LVEDD) and cardiothoracic ratio (CRT) were measured within 24 hours before or after catheterization. All CHF patients received conventional therapy and the rates of cardiac death and rehospitalization were used as end points during 3-year follow up. RESULTS: (1) LVEDD, CRT, PCWP and BNP were increased in patients with cardiac events compared with patients without cardiac events (P < 0.01). (2) Multivariant logistic analysis showed that PCWP (OR = 1.423, 95% CI 1.163 - 1.741) and BNP (OR = 1.005, 95% CI 1.002 - 1.007) were the independent factors for cardiac events. (3) The area under the receiver operating curve (ROC) of BNP and PCWP to predict cardiac death was 0.846 (95% CI 0.771 - 0.922) and 0.762 (95% CI 0.666 - 0.875), respectively. The sensitivity was 76.5% and the specificity was 75.2% with BNP cutoff point of 720.5 ng/L, and the sensitivity was 68.1% and the specificity was 76.2% with PCWP cutoff point of 19.5 mm Hg (1 mm Hg = 0.133 kPa) for predicting cardiac deaths. (4) The survival rate of patients with BNP < or = 702.5 ng/L and PCWP < or = 19.5 mm Hg were significantly higher than that in patients with BNP > 702.5 ng/L (OR = 4.383, 95% CI 1.407 - 13.650) and PCWP > 19.5 mm Hg (OR = 2.843, 95% CI 1.013 - 8.854). CONCLUSION: Both plasma BNP and PCWP on admission day are independent predictors for long term cardiac events in patients with CHF.
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Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Péptido Natriurético Encefálico/sangre , Presión Esfenoidal Pulmonar , Anciano , Enfermedad Crónica , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Curva ROC , Tasa de SupervivenciaRESUMEN
Eu3+ Complexes with benzoic acid and 1,10-phenanthroline incorporated in SiO2, SiO2-B2O3 and SiO2-B2O3-Na2O matrices were prepared via the sol-gel method. Eu-doped SiO2, SiO2-B2O3 and SiO2-B2O3-Na2O luminescence materials were synthesized. The luminescence of Eu3+ was studied with excitation spectra and emission spectra. Different forms of dopants could influence the luminescence properties. The structure of Eu-doped glass was studied by comparing IR, TEM and XRD. The results showed that after the materials were annealed at 1 000 degrees C the structure was very stable because ingredient was already removed totally. The emission spectrum showed that the typical optical spectrum of Eu3+ is 5D0 --> 7Fj (j = 1, 2) at 588 nm and 614 nm. Comparing EuCl3 with Eu3+ complexes with benzoic acid and 1,10-phenanthroline as dopant, the latter has strong luminescence property though it has small mass fraction. The luminescence intensity of Eu(3+)-doped SiO2-B2O3 glass material was weaker than that of Eu(3+)-doped SiO2 glass material, and the former's spectrum showed that there were Si-O-B bonds. The luminescence intensity of Eu3+ was quenched by this kind of structure. The luminescence intensity of Eu(3+)-doped SiO2-B2O3-Na2O glass material was greatly increased, and the infrared spectrum illustrated that there was not vibration absorption of Si-O-B bonds. Probably Na replaced B, and Si-O-Na bonds formed. This kind of structure could enhance luminescence intensity of Eu3+ to some extend.
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Some novel binary and ternary complexes of rare earth (Tb) with N-phenylanthranilic acid and 1,10-phenanthroline were synthesized and their compositions were characterized by elemental analysis. The compositions of the complexes have been confirmed to be TbL3. 4H2O and TbL3 phen.2H20 (L: N-phenylanthranilic acid, phen: 1;10-phenanthroline). The spectroscopic properties of the complexes were discussed. The result shows that the luminescence intensities of binary and ternary complexes were decreased by N-phenylanthranilic acid and 1,10-phenanthroline. It is indicated that the intensity of Tb depends on the structure of ligands. The structure, energy transfer and energy matching were studied, and it is concluded that the structure of complex affects the luminescence properties of the complexes.
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Fenamatos/química , Fluorescencia , Compuestos Organometálicos/química , Fenantrolinas/química , Terbio/química , Compuestos Organometálicos/síntesis química , Espectrometría de Fluorescencia , Espectrofotometría Infrarroja , Espectrometría RamanRESUMEN
OBJECTIVE: To determine the correlation between the serum level of B-natriuretic peptide (BNP) and hemodynamic variables and to evaluate the diagnostic value of BNP in patients with decompensated heart failure (HF). METHODS: BNP levels (TRIAGE BIOSITE Diagnostics, San Diego, USA) were obtained by a rapid immunofluorescence assay in 117 patients with dyspnea including cardiogenic group (75 patients) and lung disease (42 patients). Hemodynamic parameters of 53 patients [male 28, female 25, mean age (71.6 +/- 9.8) years] with HF were determined and left ventricular end-diastolic diameter (LVEDD) of all patients were measured by echocardiogram. RESULTS: Pulmonary capillary wedge pressure (PCWP, mm Hg), mean pulmonary arterial pressure (MPAP, mm Hg), right atrial pressure (RAP, mm Hg) and BNP (ng/L) levels according to New York Heart Association (NYHA) class were: 16.10 +/- 3.50, 22.50 +/- 4.68, 3.11 +/- 1.90, 271.25 +/- 159.29 in NYHA class II, respectively; 21.50 +/- 4.42, 28.60 +/- 9.35, 8.95 +/- 3.86, 619.58 +/- 237.48 in NYHA class III; 29.28 +/- 8.61, 36.50 +/- 12.32, 15.27 +/- 4.96, 1519.28 +/- 618.62 in NYHA class IV (P < 0.01-0.05), respectively. PCWP, MPAP, RAP and plasma BNP levels were directly proportional to cardiac function. The plasma BNP levels had also significant positive correlations with PCWP, MPAP, RAP, (r = 0.59, 0.50, 0.32, P < 0.05-0.01). BNP level [(918.48 +/- 453.25) ng/L] of the group with LVEDD (n = 24) > or = 60 mm was much higher than that of the group with LVEDD (n = 29) < 60 mm [(298.58 +/- 167.51) ng/L]. However, the latter was significantly higher than that in pulmonary dyspnea group with a normal left and right ventricular end-diastolic diameter [(35.4 +/- 26.4) ng/L, P < 0.01]. There was a great difference of BNP between cardiogenic dyspnea group [(761.30 +/- 480.47) ng/L]and lung dyspnea group [(35.4 +/- 26.4) ng/L], P < 0.01. CONCLUSIONS: The plasma BNP levels had significant positive correlations with PCWP, MPAP, RAP. BNP is a cardiac neurohormone secreted from cardiac ventricles as a response to ventricular volume expansion and pressure overload. Rapid testing BNP should be of help to differentiate pulmonary dyspnea from cardiac etiologies.