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1.
ACS Appl Mater Interfaces ; 16(9): 11835-11848, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38382008

RESUMO

Metal-organic frameworks (MOFs) are emerging as promising materials for water purification membranes, owing to their uniform microporous structures and chemical functionalities. Here, we report a simple procedure for depositing MOF-based nanofiltration membranes on commercial TiO2 ceramic tubular supports, completely avoiding the use of dispersants or binders. Zeolite imidazolate frameworks-8 (ZIF-8) nanocrystals were synthesized in methanol at room temperature and subsequently coated with an amorphous SiO2-ZrO2 gel to generate a dispersion of ZIF-8@SiO2-ZrO2 core-shell nanoparticles. The amorphous SiO2-ZrO2 gel served as a binding agent for the ZIF-8 nanocrystals, thus forming a defect-free continuous membrane layer. After repeating the coating twice, the active layer had a thickness of 0.96 µm, presenting a rejection rate >90% for the total organic carbon in an aquaculture effluent and in a wastewater treatment plant, while reducing the concentration of trimethoprim, here used as a target pollutant. Moreover, the oxide gel provided the MOF-based active layer with good adhesion to the support and enhanced its hydrophilicity, resulting in a membrane with excellent mechanical stability and resistance to fouling during the crossflow filtration of the real wastewater samples. These results implied the high potential of the MOF-based nanocomposite membrane for effective treatment of actual wastewater streams.

2.
Sci Total Environ ; 851(Pt 2): 158360, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36041623

RESUMO

Post thermal treatment of bulk graphitic carbon nitride (g-C3N4) by ammonia gas acts as a significant structure regulation approach, while pure ammonia-assisted g-C3N4 synthesis from precursors like melamine is rarely investigated. Here we prove the synthesis of N-defects abundant carbon nitride nanosheets (ACN) through a one-pot thermal polymerization of melamine in pure ammonia gas, for photocatalytic organic pollutant removal in water and H2 evolution applications. Compared to bulk g-C3N4 (BCN), ACN-550 (ACN prepared at 550 °C) exhibited thin-layered porous morphology with higher surface area and abundant N defects, resulting in wider distribution of active sites. Moreover, the abundant N defects in the heptazine heterocycle structure could change the electronic structure of g-C3N4, leading to more efficient transport of photogenerated charge carriers and enhanced photoreduction potential, which gives rise to notable improvement activities in photocatalytic reaction. With superoxide ion radical and photoinduced holes as the predominant reactive species, ACN-550 realized efficient photocatalytic bisphenol A (BPA) degradation, which is 1.6- and 4.7-fold high over commercial TiO2 (P25) and BCN, respectively. ACN-550 exhibited excellent reusability and stability in five consecutive photocatalytic BPA degradation tests. In photo-reductive H2 production system by ACN-550, 761.8 ± 4.3 µmol/h/g H2 was produced, which was 11.6-fold as high as that by BCN.


Assuntos
Poluentes Ambientais , Amônia , Catálise , Superóxidos , Água
3.
J Colloid Interface Sci ; 608(Pt 2): 1334-1347, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34739993

RESUMO

Acid treatment serves as an effective engineering strategy to modify the structure of graphitic carbon nitride (g-C3N4) for enhanced metal-free photocatalysis, while their lacks a comprehensive understanding about the impacts of different acid species and acid treatment approaches on the intrinsic structure and properties of g-C3N4 and structure-activity relationships are ambiguous. Employing inorganic/organic acids including hydrochloric acid (HCl), nitric acid (HNO3), acetic acid (HAc), sulphuric acid (H2SO4), or oxalic acid (H2C2O4) as treatment acids, herein, we compare the impacts of different acid pretreatment approaches on the structure and properties of g-C3N4. Due to different acid-melamine interaction modes and the activation roles of various acids, the obtained g-C3N4 samples exhibit varied structures, physiochemical properties and photocatalytic activities. Compared with bulk graphitic carbon nitride (BCN), g-C3N4 prepared by acid pretreatment show enhanced photocatalytic performance on bisphenol A (BPA) degradation. The photocatalytic degradation rates of BPA by g-C3N4 prepared by HNO3, HAc, H2SO4, H2C2O4, or HCl pretreatment are about 2.2, 2.7, 2.8, 3.2 and 3.8 folds faster than that by BCN. HCl pretreatment proves to be the optimal approach, with the derived g-C3N4 (HTCN) showing more intact heptazine structural units, and increased specific surface area, which promote the exposure of more active sites, accelerate charge transfer, and give rise to a notable improvement in photocatalysis, eventually. Mechanistic investigations through quenching experiments and electron paramagnetic resonance (EPR) characterization unveil that superoxide ion radical (O2-) and photo-induced holes (h+) worked principally in the photodegradation reaction. This work provides new insights for the rational selection of acid types and treatment methods to synthesize metal-free carbon nitrides with improved activity for photocatalytic applications.


Assuntos
Poluentes Ambientais , Grafite , Catálise , Compostos de Nitrogênio
4.
BMC Cardiovasc Disord ; 21(1): 369, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34340681

RESUMO

BACKGROUND: The optimum lipid indexes, predicting the coronary lesion in postmenopausal women are not clear. OBJECTIVE: To evaluate the optimum lipid predicter for coronary lesion in routine and advanced lipid tests. METHOD: 300 postmenopausal women were enrolled and assigned into coronary heart disease (CHD) Group (242), and non-CHD Group (58). Routine and advanced lipid indexes were measured with standard laboratory test and nuclear magnetic resonance (NMR) spectroscopy. The correlation and predictivities for CHD of routine and advanced lipid indexes were performed with Logistic regression, Spearman correlation analysis and receiver operating characteristic (ROC). RESULTS: Age (hazard ratio (HR) 2.58, 95% confidence interval (CI) 1.08-5.86, P = 0.03), apolipoprotein B (ApoB) (HR 1.35, 95% CI 1.15-1.59, P < 0.001), corrected particles of low-density lipoprotein (LDL-p-corr) (HR 1.05, 95% CI 1.03-1.06, P < 0.001) and corrected particles of non-high-density lipoprotein (non-HDL-p-corr) (HR 1.02, 95% CI 1.01-1.03, P < 0.001) were the risk factors of CHD. LDL cholesterol (LDL-C), LDL-p, LDL-p-corr, HDL cholesterol (HDL-C), non-HDL cholesterol (non-HDL-C), non-HDL-p and non-HDL-p-corr were in linear correlation with Gensini score. Advanced lipid indexes LDL-p (area under curve (AUC) = 0.750, P = 0.02), LDL-p-corr (AUC = 0.759, P = 0.02), non-HDL-p (AUC = 0.693, P = 0.03) and non-HDL-p-corr (AUC = 0.699, P = 0.03) were more predictive for CHD than the routine ones (LDL-C and non-HDL-C). CONCLUSION: In postmenopausal women, age, ApoB, LDL-p-corr and non-HDL-p-corr were risk factors of CHD. Compared with traditional lipid items, LDL-p, LDL-p-corr, non-HDL-p and non-HDL-p-corr may be better lipid indexes for CHD in postmenopausal women.


Assuntos
Apolipoproteína B-100/sangue , LDL-Colesterol/sangue , Doença da Artéria Coronariana/diagnóstico , Espectroscopia de Ressonância Magnética , Pós-Menopausa/sangue , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , HDL-Colesterol/sangue , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/etiologia , Estudos Transversais , Feminino , Fatores de Risco de Doenças Cardíacas , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Medição de Risco
5.
BMC Cardiovasc Disord ; 21(1): 41, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33468066

RESUMO

BACKGROUND: Lp(a) and LDL-C are both risk factors of atherosclerotic cardiovascular disease (ASCVD). But there was a contradiction point in LDL-C and Lp(a) control. The appropriate level of LDL-C and Lp(a) in the prevention of ASCVD is still pending. OBJECTIVE: To investigate the correlation of Lp(a) and coronary atherosclerotic lesion, and find out the balance point in LDL-C and Lp(a) control. METHOD: 3449 patients were divided to coronary atherosclerotic heart disease (CAHD) Group and Non-CAHD Group based on the result of coronary angiography. The clinical characteristics were compared, and Logistic regressions were applied to find the CAHD risk factors in total, High-LDL-C Group (LDL-C ≥ 100 mg/dL) and Low-LDL-C Group (LDL-C < 100 mg/dL) patients. Spearman correlation analysis of Lp(a), LDL-C and Gensini Score was performed in patients with different LDL-C concentration. RESULTS: Except male and diabetes, the traditional CAHD risk factors were well matched between two groups. But triglyceride, LDL-C and Lp(a) were higher, HDL-C and Apo-A1 were lower in CAHD group (2771). In the Logistic regression analysis, diabetes, LDL-C and Lp(a) are risk factors of CAHD in all patients, while in High-LDL-C Group, they were age, LDL-C, non-HDL-C and ApoB, in Low-LDL-C Group, they were age, Lp(a) and ApoB. Lp(a) correlated with Gensini with coefficient r = 0.41 in all patients, 0.67 in Low-LDL-C Group and 0.32 in High-LDL-C Group. The coefficient r for Lp(a) and Gensini decreased, while the r for LDL-C and Gensini increased with LDL-C concentration increasing. The two fitted lines of rs crossed at LDL-C = 2.7 mmol/L (104 mg/dL). CONCLUSION: Lp(a) was the risk factor of CAHD in patients with LDL-C < 100 mg/dL. The correlation between Lp(a) and Gensini was influenced by LDL-C concentration, and the correlation was stronger than LDL-C when LDL-C < 104 mg/dl.


Assuntos
LDL-Colesterol/sangue , Doença da Artéria Coronariana/sangue , Estenose Coronária/sangue , Dislipidemias/sangue , Lipoproteína(a)/sangue , Idoso , Biomarcadores/sangue , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/etiologia , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/etiologia , Estudos Transversais , Dislipidemias/complicações , Dislipidemias/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença
6.
Exp Ther Med ; 18(4): 2497-2502, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31572501

RESUMO

This study explored the clinical application of ventriculoperitoneal (VP) shunting in treating traumatic brain injury (TBI). A retrospective analysis was performed on 100 patients who had hydrocephalus due to TBI and were admitted to Shanxian Central Hospital from February 2012 to June 2016. Among these patients, 50 underwent VP shunting surgery and were assigned to the experimental group. The remaining 50 underwent lumboperitoneal (LP) shunting surgery and were assigned to the control group. Twenty days after surgery, all patients were evaluated for clinical outcomes, neurological deficit scores and complications. The results were compared between the two groups. Patients in the experimental group were further separated into three subgroups according to the severity of hydrocephalus, and clinical outcomes were compared among the subgroups. It was found that the effective rate in the experimental group was significantly higher than that in the control group, and the difference was statistically significant (P<0.05). The effective rate in the mild hydrocephalus subgroup was significantly higher than that in the severe hydrocephalus subgroup, with a statistically significant difference (P<0.05). The effective rate in the moderate hydrocephalus subgroup was significantly higher than that in the severe hydrocephalus subgroup, with a statistically significant difference (P<0.05). The incidence of complications in the control group was significantly higher than that in the experimental group, and the difference was statistically significant (P<0.05). The postoperative neurological deficit score in the experimental group was significantly lower than that in the control group, and the difference was statistically significant (P<0.05). In conclusion, patients with hydrocephalus due to TBI had better clinical outcome when treated with VP shunting than those treated with LP shunting. Moreover, a better outcome was observed when the patient had milder hydrocephalus. Therefore, the early diagnosis and timely treatment with VP shunting are of great importance for patients with hydrocephalus.

7.
Adv Exp Med Biol ; 1155: 13-24, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31468382

RESUMO

Taurine is a sulfur-containing amino acid which has strong activities in enhancing immunity. Gut microbiota is closely interrelated with intestinal mucosal immunity, but the effects and mechanisms of taurine on intestinal microbiota and mucosal immune cells under an immunosuppressive condition remain unclear. This study was conducted to investigate the effect of taurine on gut microbiota and immune cells in Peyer's patches (PPs) of dexamethasone (Dex)-induced immunosuppressive mice. Mice (4-week-old, Male) were randomly divided into three groups: the Control group (n = 12), the Dex-induced immunosuppressive model group (n = 12) and the taurine intervention group (n = 12). The model was established by Dex injection for 7 days and the taurine intervention group was gavaged 100 mg/kg soluble taurine for 30 days. The changes of intestinal microbiota and immune cells in PPs were tested by denaturing gradient gel electrophoresis (DGGE) and flow cytometry, respectively. Results showed that the microbiota in immunosuppressive mice was obvious different compared with control group, in which, the Lachnospiraceae and Ruminococcaceae groups were significantly reduced, and their reduction were reversed after taurine intervention. Compared to the control group, the total cell number in PPs, as well as the subsets of CD3+ cells (T cells), CD19+ cells (B cells) in model groups were significantly lower, and they were dramatically improved after taurine treatment. Our results suggested that taurine has a positive effect on i ntestinal homeostasis of the immunosuppressive mice.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Tolerância Imunológica , Nódulos Linfáticos Agregados/efeitos dos fármacos , Taurina/farmacologia , Animais , Homeostase , Masculino , Camundongos , Distribuição Aleatória
8.
Adv Exp Med Biol ; 1155: 381-390, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31468416

RESUMO

Taurine (2-aminoethanesulfonic acid) has positive effects on the formation of immune systems. In this study, we evaluated the effects of taurine on the development of T lymphocyte subpopulations in thymus of immunosuppresive mice. The immunosuppressed mice model was established by intraperitoneal injection of dexamethasone (Dex) for 7 days. Mice (male, Kunming strain) were randomly divided into three groups, the normal control group (Cont.), the Dex-induced immunosuppressive model group (Dex + PBS), and the taurine intervention group (Dex + TAU). Taurine was administered at a dose of 200 mg/kg for 30 days or until euthanasia. Total cell numbers in the thymi of mice were evaluated by cell count, and the flow cytometry was used to determine the proportion of different cell subsets. Our results showed that the size and weight of thymi of Dex + PBS group were significantly smaller than those of Cont. group, and taurine administration efficiently increased the thymus index. Taurine also significantly increased the number of CD4- CD8- double negative (DN), CD4+ CD8+ double positive (DP), CD4+ single positive (CD4+) and CD8+ SP (CD8+) cells compared with the Dex + PBS group, but did not affect the CD4+/CD8+ cell ratio in thymus of Dex-induced immunoseppressive mice. Our results suggested that taurine has a positive effect on thymus differentiation in Dex-induced immunosuppressive mice.


Assuntos
Diferenciação Celular , Terapia de Imunossupressão , Subpopulações de Linfócitos T/efeitos dos fármacos , Taurina/farmacologia , Timo/efeitos dos fármacos , Animais , Relação CD4-CD8 , Dexametasona , Citometria de Fluxo , Masculino , Camundongos , Distribuição Aleatória , Subpopulações de Linfócitos T/citologia
9.
J Colloid Interface Sci ; 532: 321-330, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30096526

RESUMO

Photocatalysis has been believed as one of the green and sustainable avenues to address energy and environmental crises by converting solar energy to chemical energy via reactions. Temperature is usually a vital factor controlling kinetics and thermodynamics of a reaction, but it has been less investigated in photocatalysis. In this work, the effect of reaction temperature on photocatalysis was investigated in a simple process, photocatalytic degradation of Congo Red (CR) on three typical catalysts, g-C3N4, TiO2 and ZnO, to differentiate the interfacial radical generation and reaction mechanism. The results showed that the temperature has a positive effect on the photocatalytic activity of the three catalysts. The scavenger experiments at various temperatures indicated that the generation of reactive species from the three photocatalysts is different and that the free radicals can be produced more quickly at higher temperatures, causing improved activities in photocatalysis. However, photocurrent analysis and EIS at various temperatures showed that the temperature had a different effect on recombination rate and transfer barriers of the charge carriers from each catalyst. Therefore, the dramatic enhancement in photodegradation activities probably originated from a novel mechanism of the photothermocatalytic oxidation. The interfacial reaction and mechanism from the influence of reaction temperature on the photocatalytic process was proposed.

10.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 33(3): 262-266, 2017 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-29931944

RESUMO

OBJECTIVE: To investigate the relationship between zinc finger protein(ZFP580)and ventricular remodeling after myocardial is-chemia/reperfusion(I/R) injury in rats. METHODS: Seventy-two rats were divided into sham group and I/R groups which would be tested in se-ries time of 0.5 h, 1 h, 2 h, 4 h, 1 d,7 d,14 d,28 d after reperfusion to observe the expression of ZFP580 in rat myocardium. The H9C2 cells were cultured and treated with transforming growth factor-beta1 (TGF-ß 1) to establish cardiac hypertrophy in vitro model in series time of 0 h, 8h, 16 h and 24 h. The cardiomyocyte hypertrophy morphology was measured. The mRNA levels of atrial natriuretic peptide(ANP), myosin heavey chain beta(ß -MHC) and ZFP580 genes were quantified. The protein levels of MMP-3 and ZFP580 were quantified after H9C2 cells were transfected by lentiviral-mediated ZFP580 gene. RESULTS: Myocardial I/R injury model was successfully established. Myocardial tis-sue in rats had large area infarction, and myocardial cells were eosinophilic changed. The increased level of ZFP580 protein was observed in the cardiomyocytes around infarction zone. The expression of TGF-ß 1 in myocardium was up-regulated after myocardial I/R injury. TGF-ß 1 (5 ng/ml) treatment could induce cardiomyocyte hypertrophy in H9C2 cells. TGF-ß 1 treatment increased the cell size and mRNA levels of ANP andß -MHC genes (P < 0.05), which represent degree of cardiac hypertrophy. TGF-ß 1 treatment also increased the protein levels of ZFP580 in H9C2 cells (P < 0.05). In the H9C2 cells transfected by lentiviral-mediated gene, the protein level of MMP3 was decreased (P < 0.05). CONCLUSIONS: ZFP580 is probably related with ventricular remodeling after myocardial I/R injury by involving TGF-ß 1 induced cardiomyocyte hypertrophy and attenuating MMP-3 production.


Assuntos
Isquemia Miocárdica/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Fatores de Transcrição/metabolismo , Remodelação Ventricular , Animais , Fator Natriurético Atrial/metabolismo , Linhagem Celular , Metaloproteinase 3 da Matriz/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Ratos , Traumatismo por Reperfusão , Fatores de Transcrição/genética , Transfecção , Fator de Crescimento Transformador beta1/farmacologia
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