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1.
Chem Commun (Camb) ; 58(83): 11649-11652, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36129144

RESUMO

Inducing amorphous components into Al2O3 leads to elongation of the Al-O bond and the formation of oxygen vacancies, which makes Al2O3 an independent photocatalyst for CO2 adsorption and reduction. The generation rate of CO can reach 36.5 µmol g-1 h-1, which is 6.5 times that of P25 TiO2.

2.
World J Stem Cells ; 14(1): 104-116, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35126831

RESUMO

BACKGROUND: Type 1 diabetes (T1D), a chronic metabolic and autoimmune disease, seriously endangers human health. In recent years, mesenchymal stem cell (MSC) transplantation has become an effective treatment for diabetes. Menstrual blood-derived endometrial stem cells (MenSC), a novel MSC type derived from the decidual endometrium during menstruation, are expected to become promising seeding cells for diabetes treatment because of their noninvasive collection procedure, high proliferation rate and high immunomodulation capacity. AIM: To comprehensively compare the effects of MenSC and umbilical cord-derived MSC (UcMSC) transplantation on T1D treatment, to further explore the potential mechanism of MSC-based therapies in T1D, and to provide support for the clinical application of MSC in diabetes treatment. METHODS: A conventional streptozotocin-induced T1D mouse model was established, and the effects of MenSC and UcMSC transplantation on their blood glucose and serum insulin levels were detected. The morphological and functional changes in the pancreas, liver, kidney, and spleen were analyzed by routine histological and immunohistochemical examinations. Changes in the serum cytokine levels in the model mice were assessed by protein arrays. The expression of target proteins related to pancreatic regeneration and apoptosis was examined by western blot. RESULTS: MenSC and UcMSC transplantation significantly improved the blood glucose and serum insulin levels in T1D model mice. Immunofluorescence analysis revealed that the numbers of insulin+ and CD31+ cells in the pancreas were significantly increased in MSC-treated mice compared with control mice. Subsequent western blot analysis also showed that vascular endothelial growth factor (VEGF), Bcl2, Bcl-xL and Proliferating cell nuclear antigen in pancreatic tissue was significantly upregulated in MSC-treated mice compared with control mice. Additionally, protein arrays indicated that MenSC and UcMSC transplantation significantly downregulated the serum levels of interferon γ and tumor necrosis factor α and upregulated the serum levels of interleukin-6 and VEGF in the model mice. Additionally, histological and immunohistochemical analyses revealed that MSC transplantation systematically improved the morphologies and functions of the liver, kidney, and spleen in T1D model mice. CONCLUSION: MenSC transplantation significantly improves the symptoms in T1D model mice and exerts protective effects on their main organs. Moreover, MSC-mediated angiogenesis, antiapoptotic effects and immunomodulation likely contribute to the above improvements. Thus, MenSC are expected to become promising seeding cells for clinical diabetes treatment due to their advantages mentioned above.

3.
Pain Ther ; 10(2): 1649-1662, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34595723

RESUMO

INTRODUCTION: Dexmedetomidine (DEX) as a nerve block adjuvant can significantly prolong analgesia. However, whether perineural or systemic administration of DEX is more beneficial in patients undergoing total knee arthroplasty (TKA) has not been thoroughly investigated. To this end, we evaluated the effects of perineural and systemic DEX administration on postoperative analgesia in patients undergoing TKA surgery. METHODS: We randomly assigned patients undergoing TKA under general anesthesia combined with femoral nerve block and sciatic nerve block to one of three groups: (1) ropivacaine plus perineural dexmedetomidine (DP): 0.25% ropivacaine 40 mL plus 0.5 µg/kg dexmedetomidine; (2) ropivacaine plus systemic dexmedetomidine (DS): 0.25% ropivacaine 40 mL plus systemic 0.5 µg/kg dexmedetomidine; (3) control group (C): 0.25% ropivacaine 40 mL. RESULTS: The average length of time until patients first experienced postoperative pain was significantly longer in the DP group (26.0 h [22.0-30.0 h]) than in the DS group (22.4 h [18-26.8 h]) and the control group (22.9 h [19.5-26.3 h], P = 0.001). For this result there was no significant difference between the DS and the control group. Compared with the DS and control groups, patients in the DP group had lower resting visual analogue scale (VAS) scores at 24, 48, and 72 h after surgery (P < 0.05). VAS activity scores at 12, 24, and 48 h after surgery in the DP group were lower than those in the DS and control groups, with a statistically significant difference (P < 0.05). Compared with the DS and control groups, the amount of postoperative opioids in the DP group was also significantly reduced, and the number of people needing postoperative rescue analgesia was significantly lower, with a statistical difference (P < 0.05). Meanwhile, the sleep satisfaction of patients in the DP group on the first night after surgery and the satisfaction with pain control at 72 h after surgery were both higher than those in the DS group and control group (P < 0.05). CONCLUSIONS: Perineural administration of DEX can significantly prolong the interval until patients report pain for the first time after TKA, relieve postoperative pain, reduce postoperative opioid dosage, and improve postoperative sleep quality and satisfaction with pain control. TRIAL REGISTRATION: The trial was registered at the Chinese Clinical Trial Registry, identifier ChiCTR1900025808.

4.
Chem Commun (Camb) ; 57(76): 9676-9679, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34555138

RESUMO

In this paper, it is found that the preferential growth of secondary {117} facets of Bi24O31Br10 into dominant facets would lead to higher photocatalytic activity, although the original main {213} facet has a stronger molecular oxygen adsorption ability, which illustrates that the charge separation efficiency induced by dominant/secondary facet control plays a more important role than that of O2 adsorptive performance in improving activity.

5.
J Pain Res ; 14: 527-536, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33658840

RESUMO

BACKGROUND: Both lumbosacral plexus block (LSPB) and local infiltration analgesia (LIA) can provide postoperative analgesia for patients undergoing total hip arthroplasty (THA). The current study aimed to compare the differences between LSPB and LIA on postoperative pain and quality of life (QoL) in THA patients. METHODS: A total of 117 patients aged 40-80 years, ASA I-III, were prospectively randomized into two groups: a general anesthesia plus LSPB (Group LSPB) and a general anesthesia plus LIA (Group LIA). Pain intensity and opioid consumption were recorded Within 72 hours after surgery. QoL was measured by EQ-5D and EQ-VAS questionnaires, and the incidence of postoperative pain was measured as part of the EQ-5D on day 1, day 3, day 7, and month 1, month 3, and month 6 after surgery. RESULTS: EQ-5D scores: Mobility, Self-Care, Usual Activities, Pain/Discomfort, and Anxiety/Depression were higher in Group LSPB versus Group LIA throughout six-month follow-ups (p = 0.039). The pain intensity was lower in Group LSPB than in Group LIA 0-12 h after surgery (2.41 vs 2.79, p = 0.01), but was higher in Group LSPB than in Group LIA 12-24 h (2.59 vs 2.05, p = 0.02) and 24-48 h (2.18 vs 1.73, p = 0.02) after surgery. There were no differences in opioid consumption between the groups during the first 72 postoperative hours. In the first month after surgery, more patients in Group LSPB than in Group LIA had no pain (52 vs 40, p = 0.04). CONCLUSION: Both LSPB and LIA can provide satisfactory postoperative analgesia. The LSPB is better than LIA for long-term QoL in THA patients undergoing general anesthesia. CLINICAL TRIAL REGISTRATION NUMBER: The Chinese Clinical Trial Registry (ChiCTR-INR-17012545).

6.
Nanoscale ; 13(4): 2585-2592, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33480957

RESUMO

The main process of carbon dioxide (CO2) photoreduction is that excited electrons are transported to surface active sites to reduce adsorbed CO2 molecules. Obviously, electron transfer to the active site is one of the key steps in this process. However, current catalysts for CO2 adsorption, activation, and electron reduction occur in different locations, which greatly reduce the efficiency of photocatalysis. Herein, through a spontaneous chemical redox approach, the plasmonic photocatalysts of Au-BiOCl-OV with enhanced interfacial interaction were fabricated for visible light CO2 reduction through the simultaneous adsorption, activation and in situ reduction of CO2 without a sacrificial agent. By loading gold (Au) on the oxygen vacancy (OV), Au and BiOCl-OV formed a direct and tight interface contact, whose fine structure was confirmed by SEM, TEM, EPR and XPS, which not only effectively boosts the light utilization efficiency and the light carrier separation ability, but also can simultaneously adsorb, activate and in situ reduce carbon dioxide for highly efficient visible light photocatalysis. Thanks to the synergistic influence of Au and OV, Au-BiOCl-OV exhibits excellent photocatalytic performance without sacrificial agent and outstanding stability with a high CO and CH4 production yield, reaching 4.85 µmol g-1 h-1, which were 2.8 times higher than C-Au-BiOCl-OV (obtained by traditional NaBH4 reduction). This study proposes a new strategy for the production of high-performance collaborative catalysis in photocatalytic CO2 reduction.

7.
Pain Pract ; 21(1): 37-44, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32615020

RESUMO

BACKGROUND: Propofol and sevoflurane as frequently used general anesthetics can affect postoperative pain. Our study explored whether the incidence of postoperative pain differed among patients with chronic pain undergoing total knee arthroplasty (TKA) anesthetized with sevoflurane or propofol. METHODS: Patients were randomly assigned to groups receiving either sevoflurane (Group S, n = 50) or propofol (Group P, n = 47) for anesthesia maintenance during TKA. The incidences of postoperative pain and quality of life (QoL) were measured using the EuroQol 5-Dimension (EQ-5D) scale at 1, 3, and 7 days post-operation (DPO), and 1 and 3 months post-operation (MPO). RESULTS: At 3 DPO, fewer patients reported moderate pain (P = 0.001) and more patients reported no pain (P = 0.003) in Group S than that in Group P. At 3 MPO, more patients reported no pain (P = 0.04) and fewer patients reported moderate pain (P = 0.04) in Group S than in Group P. No significant differences were found in the incidence of postoperative pain between the 2 groups of patients at the other time points. The EQ-5D scores were higher in Group S than in Group P (P = 0.022), and the difference was 0.15 at most, which was not optimal. The EQ-5D clinical results might be not very significant. CONCLUSIONS: Sevoflurane anesthesia may have potential advantages in reducing postoperative pain in patients undergoing TKA with a preoperative VAS score > 4.


Assuntos
Anestésicos Gerais/uso terapêutico , Artroplastia do Joelho/métodos , Dor Pós-Operatória/epidemiologia , Dor Pós-Operatória/prevenção & controle , Propofol/uso terapêutico , Sevoflurano/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestesia Geral/métodos , Dor Crônica/etiologia , Dor Crônica/cirurgia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/cirurgia , Qualidade de Vida
8.
Biomed Environ Sci ; 30(1): 59-63, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28245900

RESUMO

Life course epidemiology should practically illustrate how risk exposures and their dynamic changes influence the occurrence, development and prognosis of chronic diseases from early life to the elderly. This paper develops the lifespan risk exposure measurement instrument (LREMI) in the framework of retrospective study to collect lifestyle, diet, physical activity information across subjects'life courses from 18-years-old to current age. Through a pilot study, the result of the test-retest analysis demonstrated the reliability of LREMI. In Shandong Multicenter Cohort, the LREMI showed its feasibility, for it could measure the exposure spectrum on both individuals and population with different life experiences. Moreover, it had good differentiation ability for identifying cases versus controls in population-based case-control study. However, further studies should be conducted in an already available prospective cohort to ascertain that our results could match prospective data.


Assuntos
Exposição Ambiental , Métodos Epidemiológicos , Estilo de Vida , Humanos , Estudos Retrospectivos
9.
Phys Chem Chem Phys ; 19(14): 9392-9401, 2017 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-28327717

RESUMO

The development of inexpensive visible-light-driven photocatalysts is an important prerequisite for realizing the industrial application of photocatalysis technology. In this paper, an earth-abundant FeAl2O4 photocatalyst is prepared via facile solution combustion synthesis. Density functional theory and the scanning Kelvin probe technique are employed to ascertain the positions of the energy bands and the Fermi level. Phenol is taken as a model pollutant to evaluate the photocatalytic activity of FeAl2O4. The scavenger experiment results, ˙OH-trapping fluorescence technique, and electron spin resonance measurements confirm that the superoxide anion radical is the main active species generated in the photocatalytic process, which also further corroborates the proposed electronic structure of FeAl2O4. The degradation experiments and O2 temperature programmed desorption results over various samples verify that the crystallinity degree is a more important factor than the oxygen adsorption ability in determining photocatalytic activity.

10.
Dalton Trans ; 45(6): 2444-53, 2016 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-26660856

RESUMO

Porous sphere-like tricobalt tetraoxide (Co3O4)-cobalt chloride hydrate (CoCl2·6H2O, CCH) heterojunctions are obtained using a one-step facile solution combustion route. The heterostructure is confirmed by XRD, HRTEM, and XPS measurements. Their photocatalytic performances are evaluated by the degradation of methyl orange (MO) and the reduction removal of Cr(VI) ions under visible light irradiation. The heterojunction containing 81.5 wt% Co3O4 and 18.5 wt% CCH exhibits the highest photocatalytic performance, for which the pseudo-first-order reaction rate constant is 10.0 and 8.7 times that of pure Co3O4 towards MO degradation and Cr(vi) reduction, respectively. This enhancement in activity can be attributed to the effective electron transfer from the conduction band of Co3O4 to that of CCH, which is verified with a double increase of the photocurrent valve of the heterojunction sample electrode in comparison with the bare Co3O4 sample electrode. Electron paramagnetic resonance, fluorescence spectrophotometry and scavenger experiments indicate that photo-induced holes, and hydroxyl and superoxide anion radicals are the active species responsible for the photo-oxidation of MO. The reasons for the formation of these species are discussed and proposed based on the band gap structures of Co3O4 and CCH. The recycling experiment results indicate that the activity can be regained by a remedial experiment.

11.
Dalton Trans ; 44(40): 17859-66, 2015 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-26399735

RESUMO

A Ti species modified g-C3N4 photocatalyst was synthesized via an in situ hydrothermal route and the subsequent low-temperature calcination. The hydrothermal process results in not only the fabrication of TiO2/g-C3N4 heterojunctions, but also the coordination between Ti species and g-C3N4, which are verified by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The electrical resistance test confirms that the coordination can improve the electrical conductivity of composites and can make the charge transfer easier. The photoluminescence (PL) and photocurrent measurements exhibit that the hybridization enhances the separation efficiency of photo-induced electrons and holes. As a result, the Ti species modified g-C3N4 photocatalysts exhibit much higher photocatalytic H2 evolution than the simple heterojunction of TiO2/g-C3N4 obtained via a microwave method and the mechanical mixture of TiO2 and g-C3N4 under visible-light irradiation. The coordination mechanism and synthesis route of TiO2/g-C3N4 heterojunctions are proposed.

12.
Chemistry ; 21(28): 10149-59, 2015 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-26043440

RESUMO

Heterojunctions of g-C3 N4 /Al2 O3 (g-C3 N4 =graphitic carbon nitride) are constructed by an in situ one-pot hydrothermal route based on the development of photoactive γ-Al2 O3 semiconductor with a mesoporous structure and a high surface area (188 m(2) g(-1) ) acting as electron acceptor. A structure modification function of g-C3 N4 for Al2 O3 in the hydrothermal process is found, which can be attributed to the coordination between unoccupied orbitals of the Al ions and lone-pair electrons of the N atoms. The as-synthesized heterojunctions exhibit much higher photocatalytic activity than pure g-C3 N4 . The hydrogen generation rate and the reaction rate constant for the degradation of methyl orange over 50 % g-C3 N4 /Al2 O3 under visible-light irradiation (λ>420 nm) are 2.5 and 7.3 times, respectively, higher than those over pristine g-C3 N4 . The enhanced activity of the heterojunctions is attributed to their large specific surface areas, their close contact, and the high interfacial areas between the components as well as their excellent adsorption performance, and efficient charge transfer ability.

13.
J Hazard Mater ; 292: 126-36, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25814184

RESUMO

Facets coupled BiOBr with amorphous TiO2 composite photocatalysts are synthesized via an in situ direct growth approach under microwave irradiation. XRD, SEM and HRTEM characterizations indicate that the heterointerface between BiOBr and amorphous TiO2 occurs mainly on the {001} facets of BiOBr. BET and TEM verify that the heterojunctions possess higher specific surface areas and smaller amorphous TiO2 particle size than bare BiOBr and amorphous TiO2, exhibiting the inhibition function of BiOBr on the growth of TiO2 particles. XPS verifies the interaction between the two components. The degradation of methyl orange (MO) and phenol are used as the objective reaction to evaluate the photocatalytic activity of the as-prepared samples. The reaction rate constant of 15% TiO2/BiOBr composite is 3.4 times greater than that of pure BiOBr, which is attributed to its higher surface area, and efficient separation of photo-generated electron-hole pairs between BiOBr and amorphous TiO2.


Assuntos
Bismuto/química , Titânio/química , Catálise , Microscopia Eletrônica de Varredura , Processos Fotoquímicos , Difração de Raios X
14.
J Hazard Mater ; 283: 371-81, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25306536

RESUMO

Novel Al2O3/g-C3N4 heterojunction photocatalysts were fabricated through ultrasonic dispersion method. Al2O3, obtained via solution combustion, contained amorphous ingredient with lots of defect sites and was used as active component for transferring photo-induced electrons of g-C3N4. G-C3N4 was grafted surface hydroxyl groups in the presence of ammonia aqueous solution to combine with Al2O3 possessing positive charges via hydrogen bond. The XRD, SEM, element map, TEM, HRTEM, FT-IR, and XPS results indicate that these synthesized materials are two-phase hybrids of Al2O3 and g-C3N4 with interaction. The photocatalytic results for the degradation of rhodamine B (RhB) indicate that the most active heterojunction proportion is 60wt.% g-C3N4:40wt.% Al2O3, the visible light photocatalytic activity of which is 3.8 times that of a mechanical mixture. The enhanced performance is attributed to the high separation efficiency of photo-induced electrons from the LUMO of g-C3N4 injected into the defect sites of Al2O3, which is verified by photoluminescence spectroscopy (PL) and surface photovoltage (SPV) measurements. The electron paramagnetic resonance (EPR) signals and radical scavengers trapping experiments reveal holes (h(+)) and superoxide anion radical (O2(-)) are the main active species responsible for the degradation of RhB.


Assuntos
Hidróxido de Alumínio/química , Modelos Químicos , Nitrilas/química , Radical Hidroxila/química , Processos Fotoquímicos , Rodaminas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química
15.
J Hazard Mater ; 239-240: 118-27, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23021102

RESUMO

Nitrogen-doped Degussa P25 TiO2-amorphous Al2O3 composites were prepared via facile solution combustion. The composites were characterised using X-ray diffraction, high-resolution transmission microscopy, scanning electron microscopy, nitrogen adsorption-desorption measurements, X-ray photoelectron spectroscopy, UV-vis light-diffusion reflectance spectrometry (DRS), zeta-potential measurements, and photoluminescence spectroscopy. The DRS results showed that TiO2 and amorphous Al2O3 exhibited absorption in the UV region. However, the Al2O3/TiO2 composite exhibited visible-light absorption, which was attributed to N-doping during high-temperature combustion and to alterations in the electronic structure of Ti species induced by the addition of Al. The optimal molar ratio of TiO2 to Al2O3 was 1.5:1, and this composite exhibited a large specific surface area of 152 m2/g, surface positive charges, and enhanced photocatalytic activity. These characteristics enhanced the degradation rate of anionic methylene orange, which was 43.6 times greater than that of pure P25 TiO2. The high visible-light photocatalytic activity was attributed to synthetic effects between amorphous Al2O3 and TiO2, low recombination efficiency of photo-excited electrons and holes, N-doping, and a large specific surface area. Experiments that involved radical scavengers indicated that OH and O2- were the main reactive species. A potential photocatalytic mechanism was also proposed.


Assuntos
Óxido de Alumínio/química , Corantes/química , Azul de Metileno/química , Titânio/química , Poluentes Químicos da Água/química , Adsorção , Óxido de Alumínio/efeitos da radiação , Catálise , Corantes/efeitos da radiação , Temperatura Alta , Luz , Azul de Metileno/efeitos da radiação , Nitrogênio/química , Fotólise , Titânio/efeitos da radiação , Poluentes Químicos da Água/efeitos da radiação
16.
Am J Physiol Renal Physiol ; 303(5): F757-65, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22718885

RESUMO

Heat shock protein (HSP)47 is a collagen-specific molecular chaperone that is essential for the biosynthesis of collagen molecules. It is likely that increased levels of HSP47 contribute to the assembly of procollagen and thereby cause an excessive accumulation of collagens in disease processes associated with fibrosis. Although HSP47 promotes renal fibrosis, the underlying mechanism and associated signaling events have not been clearly delineated. We examined the role of HSP47 in renal fibrosis using a rat unilateral ureteral obstruction model and transforming growth factor (TGF)-ß(1)-treated human proximal tubular epithelial (HK-2) cells. An upregulation of HSP47 in both in vivo and in vitro models was observed, which correlated with the increased synthesis of extracellular matrix (ECM) proteins and expression of tissue-type plasminogen activator inhibitor (PAI)-1. Blockade of HSP47 by short interfering RNA suppressed the expression of ECM proteins and PAI-1. In addition, TGF-ß(1)-induced HSP47 expression in HK-2 cells was attenuated by ERK1/2 and JNK MAPK inhibitors. These data suggest that ERK1/2 and JNK signaling events are involved in modulating the expression of HSP47, the chaperoning effect of which on TGF-ß(1) would ultimately contribute to renal fibrosis by enhancing the synthesis and deposition of ECM proteins.


Assuntos
Proteínas da Matriz Extracelular/biossíntese , Proteínas de Choque Térmico HSP47/fisiologia , Adulto , Animais , Linhagem Celular , Colágeno Tipo I/biossíntese , Colágeno Tipo IV/biossíntese , Fibrose , Humanos , Rim/metabolismo , Rim/patologia , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Proteína Quinase 1 Ativada por Mitógeno/fisiologia , Proteína Quinase 3 Ativada por Mitógeno/fisiologia , Inibidor 1 de Ativador de Plasminogênio/biossíntese , RNA Interferente Pequeno/farmacologia , Ratos , Fator de Crescimento Transformador beta1/farmacologia , Regulação para Cima , Obstrução Ureteral/fisiopatologia
17.
J Hazard Mater ; 205-206: 164-70, 2012 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-22230756

RESUMO

A new C5H9NO·SnCl2 coordinated ionic liquid (IL) was prepared by reacting N-methyl-pyrrolidone with anhydrous SnCl2. Desulfurization of dibenzothiophene (DBT) via extraction and oxidation with C5H9NO·SnCl2 IL as extractant, H2O2 and equal mol of CH3COOH as oxidants was investigated. The Nernst partition coefficients k(N) of C5H9NO·SnCl2 IL for the DBT in n-octane was above 5.0, showing its excellent extraction ability. During the oxidative desulfurization process, the optimal molar ratio of H2O2/DBT was six. Sulfur removal of DBT in n-octane was 94.8% in 30 min at 30 °C under the conditions of H2O2/DBT molar ratio of six and V (IL):V (oil)=1:3. Moreover, the sulfur removal increased with increasing temperature because of the high reaction rate constant, low viscosity, and high solubility of dibenzothiophene-sulfone in the IL. The kinetics of oxidative desulfurization of DBT was also investigated, and the apparent activation energy was found to be 32.5 kJ/mol. The IL could be recycled six times without a significant decrease in activity.


Assuntos
Líquidos Iônicos/química , Pirrolidinonas/química , Enxofre/química , Tiofenos/química , Compostos de Estanho/química , Poluição do Ar/prevenção & controle , Óleos Combustíveis , Oxirredução
18.
Ann N Y Acad Sci ; 1140: 383-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18991938

RESUMO

Photochemical oxidation of thiophene in an n-octane/acetonitrile extraction system using O(2) as oxidant was studied. Results obtained here can be used as a reference for desulfurization of gasoline, because thiophene is one of the main components containing sulfur in fluid catalytic cracking gasoline. A 500-W high-pressure mercury lamp was used as a light source for irradiation, and air was introduced by a gas pump to supply O(2). Thiophene dissolved in nopolar n-octane solvent was photodecomposed and removed into the polar acetonitrile phase. The desulfurization rate of thiophene in n-octane was 65.2% under photoirradiation for 5 h under the conditions of air flow at 150 mL min(-1), and V(n-octane):V(acetonitrile) = 1:1. This can be improved to 96.5% by adding 0.15 g Na-ZSM-5 zeolite into the 100-mL reaction system, which is the absorbent for O(2) and thiophene. Under such conditions, the photooxidation kinetics of thiophene with O(2) and Na-ZSM-5 zeolite is first-order with an apparent rate constant of 0.6297 h(-1) and half-time of 1.10 h. The sulfur content can be reduced from 800 microL L(-1) to 28 microL L(-1).


Assuntos
Oxigênio/química , Fotoquímica/métodos , Acetonitrilas/química , Catálise , Gasolina , Cinética , Octanos/química , Oxidantes/química , Enxofre/química , Tiofenos/química , Raios Ultravioleta
19.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 32(5): 806-11, 2007 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-18007075

RESUMO

OBJECTIVE: To explore the protective effect of amlodipine on the cytotoxicity induced by contrast media (meglumine diatrizoate) in human kidney cells (HKC). METHODS: An HKC line was used. The experiment was divided into 4 groups: a model group (diatrizoate 111g/L), a prevention group (diatrizoate 111g/L+amlodipine 10(-5)mol/L), an amlodipine control group (amlodipine 10(-5)mol/L), and a culture medium control group (simple none blood serum DMEM-F12 medium). Cytotoxicity induced by meglumine diatrizoate was analysed by methyl thiazolyl tetrazolium (MTT) test, lactate dehydrogenase (LDH) assay, Hochest33258 fluorescence stained cytospins, and flow cytometric DNA analysis. The protein expression of Bax was determined by Western blot, and caspase-3 activity was examined by fluorometric method. RESULTS: In the prevention group, the cell viability increased significantly (P<0.05), LDH levels decreased (P<0.05), and the apoptosis was lower than that of the model group (P<0.05) .Bax protein expression and caspase 3 activity decreased (P<0.05). CONCLUSION: Amlodipine can inhibit the HKC apoptosis and protect the renal tubule cell from injury induced by meglumine diatrizoate.


Assuntos
Anlodipino/farmacologia , Meios de Contraste/toxicidade , Células Epiteliais/efeitos dos fármacos , Túbulos Renais/citologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular , Diatrizoato de Meglumina/toxicidade , Células Epiteliais/citologia , Humanos , Túbulos Renais/efeitos dos fármacos , Substâncias Protetoras/farmacologia
20.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 32(6): 1013-9, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18182719

RESUMO

OBJECTIVE: To construct a subtracted cDNA library of chronic intermittent hypoxia (CIH) rabbit liver by suppression subtractive hybridization (SSH). METHODS: Twenty-four rabbits were divided into 4 groups: ordinary feeding group, full-fat food group, ordinary feeding in chronic intermittent hypoxia group, and full-fat food in chronic intermittent hypoxia group. The mRNAs were extracted from different rabbit livers and converted into double-strand cDNA. After digestion with restriction enzyme, the cDNA of hyperlipidemia-sensitive rabbit group was subdivided into 2 portions and each one was lighted with different adaptors. Two rounds of both hybridization and suppression PCR obtained the differentially expressed cDNA. The PCR products were inserted into T/A vector to set up the subtractive cDNA library. The clones were selected and amplified by PCR and identified. RESULTS: Based on the pathology of the abdominal aorta and liver, and the amplified library contained 500 positive bacteria clones, including 462 clones, which had inserts from 250 to 700 bp by PCR analysis. A novel rabbit gene, Cthrc1, involved in CHI had been cloned. The GenBank Accession Number is XM_418373. CONCLUSION: The molecular mechanism of CIH promoting atherogenesis formation is made clear.


Assuntos
Biblioteca Gênica , Hipóxia/metabolismo , Fígado/metabolismo , Hibridização de Ácido Nucleico/métodos , Animais , Vetores Genéticos , Hiperlipidemias , Hipóxia/patologia , Fígado/patologia , RNA Mensageiro/genética , Coelhos
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