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1.
Nanomaterials (Basel) ; 14(7)2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38607145

RESUMEN

Thermocatalytic decomposition is an efficient purification technology that is potentially applicable to degrading chemical warfare agents and industrial toxic gases. In particular, ZrO2 has attracted attention as a catalyst for the thermocatalytic decomposition of dimethyl methylphosphonate (DMMP), which is a simulant of the nerve gas sarin. However, the influence of the crystal phase and morphology on the catalytic performance of ZrO2 requires further exploration. In this study, monoclinic- and tetragonal-phase ZrO2 (m- and t-ZrO2, respectively) with nanoparticle, flower-like shape and hollow microsphere morphologies were prepared via hydrothermal and solvothermal methods, and their thermocatalytic decomposition of DMMP was systematically investigated. For a given morphology, m-ZrO2 performed better than t-ZrO2. For a given crystalline phase, the morphology of hollow microspheres resulted in the longest protection time. The exhaust gases generated by the thermocatalytic decomposition of DMMP mainly comprised H2, CO2, H2O and CH3OH, and the by-products were phosphorus oxide species. Thus, the deactivation of ZrO2 was attributed to the deposition of these phosphorous oxide species on the catalyst surface. These results are expected to help guide the development of catalysts for the safe disposal of chemical warfare agents.

2.
Materials (Basel) ; 16(10)2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37241390

RESUMEN

Carbon monoxide (CO) is a colourless, odourless, and toxic gas. Long-term exposure to high concentrations of CO causes poisoning and even death; therefore, CO removal is particularly important. Current research has focused on the efficient and rapid removal of CO via low-temperature (ambient) catalytic oxidation. Gold nanoparticles are widely used catalysts for the high-efficiency removal of high concentrations of CO at ambient temperature. However, easy poisoning and inactivation due to the presence of SO2 and H2S affect its activity and practical application. In this study, a bimetallic catalyst, Pd-Au/FeOx/Al2O3, with a Au:Pd ratio of 2:1 (wt%) was formed by adding Pd nanoparticles to a highly active Au/FeOx/Al2O3 catalyst. Its analysis and characterisation proved that it has improved catalytic activity for CO oxidation and excellent stability. A total conversion of 2500 ppm of CO at -30 °C was achieved. Furthermore, at ambient temperature and a volume space velocity of 13,000 h-1, 20,000 ppm CO was fully converted and maintained for 132 min. Density functional theory (DFT) calculations and in situ FTIR analysis revealed that Pd-Au/FeOx/Al2O3 exhibited stronger resistance to SO2 and H2S adsorption than the Au/FeOx/Al2O3 catalyst. This study provides a reference for the practical application of a CO catalyst with high performance and high environmental stability.

3.
Molecules ; 28(6)2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36985410

RESUMEN

Cyanogen chloride (CNCl) is highly toxic and volatile, and it is difficult to effectively remove via porous substances such as activated carbon due to the weak interaction between CNCl and the adsorbent surface. Developing a highly effective elimination material against CNCl is of great importance in military chemical protection. In this work, a new metal-organic framework (MOF) CuBTC@PA-PEI (polyacrylate-polyethyleneimine) composite was prepared and exhibited excellent CNCl elimination performance in the breakthrough tests. PEI was used for the functionalization of PA with amino groups, which is beneficial to anchor with metal ions of MOF. Afterward, the growth of MOF occurred on the surface and in the pores of the matrix by molecular self-assembly via our newly proposed stepwise impregnation layer-by-layer growth method. Breakthrough tests were performed to evaluate the elimination performance of the composites against CNCl. Compared with the pristine CuBTC powder, the CuBTC@PA-PEI composite exhibited better adsorption capacity and a longer breakthrough time. By compounding with the PA matrix, a hierarchically porous structure of CuBTC@PA-PEI composite was constructed, which provides a solution to the mass transfer problem of pure microporous MOF materials. It also solves the problems of MOF molding and lays a foundation for the practical application of MOF.

4.
J Chem Phys ; 158(10): 104110, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36922144

RESUMEN

Lithium-ion batteries are key elements of electric vehicles and energy storage systems, and their accurate State of Charge (SOC) estimation is momentous for battery energy management, safe operation, and extended service life. In this paper, the Multi-Kernel Relevance Vector Machine (MKRVM) and Whale Optimization Algorithm (WOA) are used to estimate the SOC of lithium-ion batteries under different operating conditions. In order to better learn and estimate the battery SOC, MKRVM is used to establish a model to estimate lithium-ion battery SOC. WOA is used to automatically adjust and optimize weights and kernel parameters of MKRVM to improve estimation accuracy. The proposed model is validated with three lithium-ion batteries under different operating conditions. In contrast to other optimization algorithms, WOA has a better optimization effect and can estimate the SOC more accurately. In contrast to the single kernel function, the proposed multi-kernel function greatly improves the precision of the SOC estimation model. In contrast to the traditional method, the WOA-MKRVM has a higher precision of SOC estimation.

5.
Nanomaterials (Basel) ; 13(4)2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36839095

RESUMEN

NH3 is a typical alkaline gaseous pollutant widely derived from industrial production and poses great risks to humans and other biota. Metal-organic frameworks (MOFs) have excellent adsorption capacities relative to materials traditionally used to adsorb NH3. However, in practice, applications of MOFs as adsorbents are restricted because of its powder form. We prepared a polyamide (PA) macroporous polyester substrate using an emulsion template method and modified the surface with polyethylenimine (PEI) to improve the MOF growth efficiency on the substrate. The difficulty of loading the MOF because of the fast nucleation rate inside the PA macroporous polyester substrate was solved using a stepwise impregnation layer-by-layer (LBL) growth method, and a PA-PEI-MOF303(Al) hierarchical pore composite that very efficiently adsorbed NH3 was successfully prepared. The PA-PEI-MOF303(Al) adsorption capacity for NH3 was 16.07 mmol·g-1 at 298 K and 100 kPa, and the PA-PEI-MOF303(Al) could be regenerated repeatedly under vacuum at 423 K. The NH3 adsorption mechanism was investigated by in situ Fourier transform infrared spectroscopy and by performing two-dimensional correlation analysis. Unlike for the MOF303(Al) powder, the formation of multi-site hydrogen bonds between Al-O-Al/C-OH, N-H, -OH, C=O, and NH3 in PA-PEI-MOF303(Al) was found to be an important reason for efficient NH3 adsorption. This study will provide a reference for the preparation of other MOF-polymer composites.

6.
Molecules ; 27(20)2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36296717

RESUMEN

Cyanide gas is highly toxic and volatile and is among the most typical toxic and harmful pollutants to human health and the environment found in industrial waste gas. In the military context, cyanide gas has been used as a systemic toxic agent. In this paper, we review cyanide gas elimination methods, focusing on adsorption and catalysis approaches. The research progress on materials capable of affecting cyanide gas adsorption and catalytic degradation is discussed in depth, and the advantages and disadvantages of various materials are summarized. Finally, suggestions are provided for future research directions with respect to cyanide gas elimination materials.


Asunto(s)
Cianuros , Contaminantes Ambientales , Humanos , Residuos Industriales , Adsorción , Catálisis
7.
RSC Adv ; 11(8): 4444-4453, 2021 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-35424377

RESUMEN

Ru(ii) complexes have attracted increasing attention as promising antitumor agents for their relatively low toxicity, high affinity to DNA molecules, and correlation with multiple targets. Meanwhile, quinolones are synthetic antibacterial agents widely used in the clinical practice. In this paper, two novel Ru(ii) complexes coordinated by levofloxacin (LOFLX), [Ru(bpy)2(LOFLX)]·2ClO4 (1), and [Ru(dmbpy)2(LOFLX)]·2ClO4 (2) (bpy = 2,2'-bipyridine, dmbpy = 4,4'-dimethyl-2,2'-bipyridine) were synthesized with high efficiency under microwave irradiation and characterized by ESI-MS, 1H NMR, and 13C NMR. The binding behavior of these complexes with double-strand calf thymus DNA(CT-DNA) was investigated using spectroscopy, molecular docking, and density functional theory calculations. Results showed that 2 exhibited higher binding affinity than 1 and LOFLX. Further studies showed that 2 could induce the G2/M phase arrest of A549 cells via DNA damage. In summary, these results indicated that 2 could be developed as a potential anticancer agent in treatment of lung cancer through the induction of cell cycle arrest at G2/M phase by triggering DNA damage.

8.
Zhongguo Zhong Yao Za Zhi ; 38(10): 1595-600, 2013 May.
Artículo en Chino | MEDLINE | ID: mdl-23947145

RESUMEN

Lipid accumulation in the vessel wall and tunica intima vasorum pathological changes are important factors in the development of atherosclerosis, which are closely related with hemodynamics. In this paper, we established a model of local low shear stress in rabbits using carotid artery cannula and a high cholesterol diet for 2 weeks, 4 weeks and 8 weeks. The effects of Shenlian extract on blood flow, vascular pathology formation and lipid metabolism were assessed by electromagnetic blood flow meter and hematoxylin-eosin staining of the proximal end in carotid artery at different times. The results demonstrate that the relationship between blood flow and shear stress for control, atorvastatin, Shenlian extract high-dose, Shenlian extract middle-dose, and Shenlian extract low-dose were linearly related. The blood flow and the shear stress of proximal end in carotid artery of Shenlian extract (1.12, 2.24, 4.48 g x kg(-1)), and atorvastatin (4.7 x 10(-4) g x kg(-1)) were significantly (P < 0.05)increased compared with the control. Plasma total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) ,and high density lipoprotein cholesterol (HDL-C) were markedly decreased with the increasing of dose and time. This study is the first to prove that the inhibition of Shenlian extract on low shear stress (LSS) induces rabbits carotid atherosclerosis with increasing blood flow and decreasing lipids and vessel pathological changes.


Asunto(s)
Enfermedades de las Arterias Carótidas/tratamiento farmacológico , Medicamentos Herbarios Chinos/administración & dosificación , Animales , Fenómenos Biomecánicos , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Arterias Carótidas/química , Arterias Carótidas/efectos de los fármacos , Arterias Carótidas/patología , Arterias Carótidas/fisiopatología , Enfermedades de las Arterias Carótidas/patología , Enfermedades de las Arterias Carótidas/fisiopatología , Humanos , Masculino , Conejos , Estrés Mecánico
9.
Zhongguo Zhong Yao Za Zhi ; 38(6): 791-4, 2013 Mar.
Artículo en Chino | MEDLINE | ID: mdl-23717953

RESUMEN

The effect of adventitia on the occurrence and development of atherosclerosis (As) is getting more attentions. Fibroblasts, mast cells, dendritic cells, vasa vasorums, vascular-associated lymphoid tissues, and vascular peripheral nerves are related to the occurrence and development of As. This essay summarizes studies on the changes in adventitia in As process and its effect on the occurrence and development of As, as well as the latest progress.


Asunto(s)
Adventicia/patología , Aterosclerosis/patología , Adventicia/efectos de los fármacos , Adventicia/metabolismo , Animales , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/metabolismo , Progresión de la Enfermedad , Humanos
10.
Life Sci ; 91(11-12): 402-408, 2012 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-22906633

RESUMEN

AIMS: The present work investigated the underlying mechanism for the positive inotropic effect of liguzinediol (LZDO) in isolated rat hearts. MAIN METHODS: Isolated rat heart perfusion, intracellular action potential recording, patch clamp and Ca2+ imaging were used to measure the isolated rat heart contractility, action potential duration, L-type Ca2+ current and sarcoplasmic reticulum (SR) Ca2+ transient in rat cardiomyocyte, respectively. KEY FINDINGS: LZDO (1, 10, and 100µM) significantly enhanced the inotropy of isolated rat hearts, but not heart rates. Nimodipine (1µM, an L-type Ca2+ channel antagonist), ruthenium red (5µM, a ryanodine receptor inhibitor) and thapsigargin (2µM, an irreversible SR Ca2+ ATPase inhibitor) completely blocked the positive inotropic effect of LZDO. LZDO significantly enhanced the intracellular Ca2+ transient in rat cardiomyocyte. However, LZDO (100µM) did not increase L-type Ca2+ channel current. Moreover, LZDO (100µM) restored the depletion effect of caffeine on Ca2+ transient. The following compounds also failed to block the positive inotropic effect of LZDO (100µM): ß-AR antagonist (propranolol 1µM), phosphodiesterase (PDE) inhibitor (IBMX 5µM), Na+-K+ ATPase inhibitor (ouabain 1µM), α(1)-AR antagonist (prazosin 1µM), dopamine D1 receptor antagonist (SCH23390 1µM) and Na+-Ca2+ exchange inhibitor (KB-R7943 1µM). SIGNIFICANCE: The positive inotropic effect of LZDO in isolated rat hearts was mediated through an elevation of SR Ca2+ transient, which may act on SR Ca2+ ATPase. LZDO has a unique biological mechanism that may prove effective in treating heart failure in clinic.


Asunto(s)
Cardiotónicos/farmacología , Corazón/efectos de los fármacos , Pirazinas/farmacología , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/efectos de los fármacos , 1-Metil-3-Isobutilxantina/farmacología , Animales , Cafeína/farmacología , Cardiotónicos/antagonistas & inhibidores , Relación Dosis-Respuesta a Droga , Corazón/fisiología , Masculino , Contracción Miocárdica/efectos de los fármacos , Contracción Miocárdica/fisiología , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/fisiología , Nimodipina/farmacología , Ouabaína/farmacología , Prazosina/farmacología , Propranolol/farmacología , Ratas , Ratas Sprague-Dawley , Rojo de Rutenio/farmacología , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/antagonistas & inhibidores , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/fisiología , Tapsigargina/farmacología
11.
Zhongguo Zhong Yao Za Zhi ; 36(23): 3338-43, 2011 Dec.
Artículo en Chino | MEDLINE | ID: mdl-22393747

RESUMEN

OBJECTIVE: To evaluate the effects of Tiangou Jiangya capsule on blood pressure and hemodynamics in anesthetized Beagle dogs. METHOD: Anesthetized dogs were divided into five groups: Tiangou Jiangya capsule 3-dose groups as 1.6, 3.2, 6.4 g x kg(-1), positive control group was giving captopril, negative control was giving 0.5% CMC-Na, duodenal administration. The blood pressure and hemodynamic changes were observed. RESULT: The systolic blood pressure of middle-dose Tiangou Jiangya capsule group was significantly reduced at 30 min after administration. The systolic blood pressure (SAP) and diastolic blood pressure (DAP) of high-dose group of Tiangou Jiangya capsule was significantly reduced at 15 min to 90 min after administration. High-dose Tiangou Jiangya capsule can also significantly reduce cardiac work (LVW) and total peripheral resistance (TPR). Tiangou Jiangya capsule had no significant effect on the other hemodynamic parameters and myocardial oxygen consumption. CONCLUSION: Tiangou Jiangya capsule has a significant effect on reducing blood pressure, which is related to the reducing total peripheral resistance and reducing cardiac work. The result can provide a reference to further clarify the Tiangou Jiangya capsule mechanism on reducing blood pressure.


Asunto(s)
Antihipertensivos/uso terapéutico , Alcoholes Bencílicos/uso terapéutico , Flavonoides/uso terapéutico , Furanos/uso terapéutico , Glucósidos/uso terapéutico , Hemodinámica/efectos de los fármacos , Hipertensión/tratamiento farmacológico , Lignanos/uso terapéutico , Animales , Antihipertensivos/administración & dosificación , Antihipertensivos/farmacología , Alcoholes Bencílicos/farmacología , Presión Sanguínea/efectos de los fármacos , Modelos Animales de Enfermedad , Perros , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Femenino , Flavonoides/farmacología , Furanos/farmacología , Glucósidos/farmacología , Frecuencia Cardíaca/efectos de los fármacos , Lignanos/farmacología , Masculino , Consumo de Oxígeno/efectos de los fármacos , Resistencia Vascular/efectos de los fármacos
12.
J Ethnopharmacol ; 124(1): 98-102, 2009 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-19527823

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Neferine was isolated from green seed embryo of Nelumbo nucifera Gaertn which has been used as an anti-obesity agent in traditional Chinese herbal medicine. AIM OF THE STUDY: This study was conducted to investigate the effects of neferine on enhancing insulin sensitivity in insulin resistant rats compared with rosiglitazone and to potentially reveal its role in mediating the anti-obesity properties of Nelumbo nucifera Gaertn. MATERIALS AND METHODS: Fasting blood glucose (FBG), fasting blood insulin (FINS), triglycerides (TG) and tumor necrosis factor-alpha (TNF-alpha) were measured, and the oral glucose tolerance test for 2-h plasma glucose level (2-h PG) was carried out. The glucose infusion rate (GIR) was used to measure the insulin sensitivity by hyperinsulinemic euglycemic clamp technique. RESULTS: The levels of FBG, FINS, TG, TNF-alpha and 2-h PG all decreased significantly in the rosiglitazone and neferine groups compared with the insulin resistance (IR) model group. Neferine diminished the 2-h PG more than did rosiglitazone treatment. Compared to the IR model group, the treatments of neferine and rosiglitazone remarkably increased GIRs but no difference between these two treatments themselves was evident. CONCLUSIONS: These data demonstrate that neferine has effects similar to rosiglitazone in decreasing fasting blood glucose, insulin, TG, TNF-alpha and enhancing insulin sensitivity in insulin resistant rats.


Asunto(s)
Bencilisoquinolinas/farmacología , Glucemia/metabolismo , Hipoglucemiantes/farmacología , Resistencia a la Insulina/fisiología , Insulina/sangre , Nelumbo/química , Extractos Vegetales/farmacología , Animales , Fármacos Antiobesidad/farmacología , Fármacos Antiobesidad/uso terapéutico , Bencilisoquinolinas/uso terapéutico , Femenino , Prueba de Tolerancia a la Glucosa , Hipoglucemiantes/uso terapéutico , Obesidad/prevención & control , Fitoterapia , Extractos Vegetales/uso terapéutico , Ratas , Ratas Wistar , Rosiglitazona , Semillas , Tiazolidinedionas/farmacología , Tiazolidinedionas/uso terapéutico , Triglicéridos/sangre , Factor de Necrosis Tumoral alfa/sangre
13.
Life Sci ; 84(7-8): 250-6, 2009 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-19133277

RESUMEN

AIMS: Diabetes mellitus is associated with changes of alpha(1)-adrenoceptor (alpha(1)-AR) on heart electrical function and expression. In this study, we investigated the ionic basis underlying abnormal alpha(1)-AR mediated QT prolongation in the diabetic rat hearts. MAIN METHODS: Electrophysiological and biochemical techniques were used in Streptozotocin (STZ)-induced diabetic and control rat hearts. KEY FINDINGS: In both control and diabetic rats, the alpha(1)-AR agonist, phenylephrine (PE, 10-100 microM) prolonged the rate-corrected QT intervals (QTc) and action potential durations at 30% (APD(30)) and 90% (APD(90)) repolarization levels with the increased QTc and APD(90) significantly greater in diabetic rats. PE significantly decreased the transient outward K(+) current (I(to)) and the steady-state K(+) current (I(ss)) in both control and diabetic rats but had no effects on the delayed rectifier K(+) current (I(k)). However, PE induced a greater reduction mainly in the I(ss), but not I(to), in diabetic rats. Furthermore, using RT-PCR and Western blot analyses, we found that alpha(1A)-ARs were over-expressed in the left ventricular tissues of the diabetic rat hearts at both the mRNA and the protein levels. SIGNIFICANCE: These data suggested that in diabetic hearts, a greater sensitivity of the alpha(1A)-AR mediated the larger suppression of I(ss) and resulted in a more prolonged APD(90) and QTc. Thus, higher alpha(1A)-AR expression levels in diabetic heart may underlie this type of diabetic cardiomyopathy and suggests that alpha(1A)-AR may serve as a therapeutic target.


Asunto(s)
Diabetes Mellitus Experimental/fisiopatología , Electrocardiografía , Receptores Adrenérgicos alfa 1/fisiología , Potenciales de Acción/efectos de los fármacos , Animales , Masculino , Fenilefrina/farmacología , Canales de Potasio/efectos de los fármacos , Canales de Potasio/fisiología , ARN Mensajero/análisis , Ratas , Ratas Sprague-Dawley , Receptores Adrenérgicos alfa 1/clasificación , Receptores Adrenérgicos alfa 1/genética , Estreptozocina
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