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Photocatalytic degradation stands as a promising method for eliminating gas-phase pollutants, with the efficiency largely hinging on the capture of photogenerated electrons by oxygen. In this work, we synthesized a porous CeO2 single crystal cube with abundant oxygen vacancies as photocatalyst, employing urea as a pore-forming agent and for gas-phase formaldehyde degradation. Compared with the CeO2 cubes without pores, the porous ones were superior in specific surface area, akin to conventional CeO2 nanoparticles. The photocatalytic degradation for gas-phase formaldehyde on porous CeO2 cubes was significantly accelerated, of which degradation rate is 3.3 times and 2.1 times that of CeO2 cubes without pores and CeO2 nanoparticles, respectively. Photoelectric tests and DFT calculations revealed that this enhancement stemmed from facilitated oxygen adsorption due to pronounced oxygen vacancies. Consequently, the capture of photoelectrons by oxygen was promoted and its recombination with holes was suppressed, along with an accelerated generation of curial free radicals such as ·OH. This work reveals the pivotal role of surface oxygen vacancies in promoting adsorbed oxygen, proposing a viable strategy to enhance the photocatalytic degradation efficiency for gas-phase pollutants.
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Cério , Formaldeído , Oxigênio , Formaldeído/química , Cério/química , Oxigênio/química , Adsorção , Porosidade , Catálise , Gases/química , Poluentes Atmosféricos/químicaRESUMO
Metal oxide semiconductors have been regarded as ideal candidates for photoelectrochemical (PEC) CO2 reduction if the contradiction between photon harvesting and photocarrier collection can be resolved. The novel three-dimensional structure provides an available approach to balancing the above-mentioned contradiction. In this work, CuBi2O4 photonic crystal photocathodes with different feature sizes were developed to realize the regulation of optoelectrical properties. The resulted photocathode displays promoted PEC activity as the enhanced photocurrent and CO2 reduction activity. Such an excellent performance was attributed to the improved efficiency of charge carrier generation and collection through extending the optical path and shortening the carrier transport distance inside films. COMSOL simulations and PEC spectroscopy analysis confirmed the promoted photon harvesting capacity and carrier dynamics. This work demonstrates a feasible strategy for developing novel photocathodes with modulated microstructures in solar-fuel conversion.
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The recombination loss of photo-carriers in photocatalytic systems fatally determines the energy conversion efficiency of photocatalysts. In this work, an electrostatic field was used to inhibit the recombination of photo-carriers in photocatalysts by separating photo-holes and photo-electrons in space. As a model structure, (010) facet-exposed BiVO4 nanowires were grown on PDMS-insulated piezo-substrate of piezoelectric transducer (PZT). The PZT substrate will generate an electrostatic field under a certain stress, and the photocatalytic behavior of BiVO4 nanowires is influenced by the electrostatic field. Our results showed that the photocatalytic performance of the BiVO4 nanowires in CO2 reduction in the negative electrostatic field is enhanced to 5.5-fold of that without electrostatic field. Moreover, the concentration of methane in the products was raised from 29% to 64%. The enhanced CO2 reduction efficiency is mainly attributed to the inhibited recombination loss of photo-carriers in the BiVO4 nanowires. The increased energy of photo-carriers and the enhanced surface absorption to polar molecules, which are CO in this case, were also play important roles in improving the photocatalytic activity of the photocatalyst and product selectivity. This work proposed an effective strategy to improve photo-carriers separation/transfer dynamics in the photocatalytic systems, which will also be a favorable reference for photovoltaic and photodetecting devices.
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The low transfer efficiency and high recombination loss of photo-induced carriers in TiO2 are significant issues that hinder its photocatalytic activity. Herein, TiO2 nanoparticles (â¼5 nm) were loaded on MnO2 nanosheets (40-60 nm) to form TiO2-MnO2 nanostructured heterojunction (0D-2D nanostructure unit), possessing a high specific surface area. The separation/transfer efficiency of photocarriers and the solar absorptivity of TiO2-MnO2 were improved, thus enhancing solar energy conversion efficiency. The enhanced transfer efficiency of carriers is associated with the 2D network of MnO2 and abundant oxygen vacancies serving as media for electron transport. The enhanced visible absorption and reduced recombination should be attributed to the narrowed bandgap and modified energy band structure. The photocurrent of TiO2-MnO2 increased obviously and the H2 production rate increased to 0.38 mmol g-1 h-1, compared with that of pure TiO2 (0.25 mmol g-1 h-1). The enhanced photocatalytic properties are also associated with the excellent water oxidation kinetics caused by MnO2 nanosheets.
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In this work, it is verified that the preferred oxidation of Sn2+ in Sn3O4 during photocatalysis is the main cause for inefficient oxygen evolution. This could be inhibited by depositing BiVO4-QDs attributed to Z-scheme charge transfer. This inhibition, along with promoted charge separation, leads to the achievement of overall water-splitting.
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It is a great challenge for achieving efficiently controllable conversion of chlorinated organics through BiVO4-based photoelectrochemical methods by improving the selective adsorption of such organics and charge separation. Herein, we have successfully fabricated SnO2/010 facet-exposed BiVO4 nanocomposites by a series of hydrothermal processes and further used as efficient photoanodes. The resulting photoanode exhibits about 6.3 times higher photoelectrochemical activity than bulk-BiVO4, especially with the efficiently controllable conversion of 2,4-dichlorophenol (2,4-DCP) to the nontoxic valuable intermediates such as catechol and pyrogallol by preferential dechlorination. Based on the 2,4-DCP adsorption curves, in situ diffuse reflectance infrared spectra, transient-state surface photovoltage responses, and photocurrent action spectra, it was clearly confirmed that the exceptional performance could be mainly attributed to the promoted selective adsorption of 2,4-DCP for efficiently modulating holes by the strong coordination interactions between -Cl with lone-pair electrons in 2,4-DCP and Bi- with empty orbits on (010) facet-exposed BiVO4 nanoflakes and to the coupled nano-SnO2 for prolonging the charge lifetime of BiVO4 by acting as the high-energy-level electron-accepting platform. This work provides a feasible strategy to develop excellent BiVO4-based photoelectrochemical methods for efficiently controlling the conversion of chlorinated organics simultaneously with energy production and recovery.
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Chronic, lowgrade inflammation associated with obesity and diabetes result from the infiltration of adipose and vascular tissue by immune cells and contributes to cardiovascular complications. Despite an incomplete understanding of the mechanistic underpinnings of immune cell differentiation and inflammation, OGlcNAcylation, the addition of Olinked Nacetylglucosamine (OGlcNAc) to cytoplasmic, nuclear and mitochondrial proteins by the two cycling enzymes, the Olinked Nacetylglucosamine transferase (OGT) and the OGlcNAcase (OGA), may contribute to finetune immunity and inflammation in both physiological and pathological conditions. Early studies have indicated that OGlcNAcylation of proteins play a proinflammatory role in diabetes and insulin resistance, whereas subsequent studies have demonstrated that this posttranslational modification could also be protective against acute injuries. These studies suggest that diverse types of insults result in dynamic changes to OGlcNAcylation patterns, which fluctuate with cellular metabolism to promote or inhibit inflammation. In this review, the current understanding of OGlcNAcylation and its adaptive modulation in immune and inflammatory responses is summarized.
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Acetilglucosamina/imunologia , Imunidade , Inflamação/imunologia , Animais , Humanos , Inflamação/patologia , N-Acetilglucosaminiltransferases/imunologia , Proteínas/imunologia , beta-N-Acetil-Hexosaminidases/imunologiaRESUMO
Ascorbic acid (AA) is an essential vitamin and plays an irreplaceable role in humans' daily life. Therefore, it is of profound significance to develop effective strategies for AA sensing. Herein, a novel bi-functional sensing strategy was developed by using carbon dots (CDs) and MnO2 nanosheet as the fluorometric/magnetic signal source. When AA was absence, the fluorescence of CDs was quenched by MnO2 nanosheet due to the inner filter effect. Neither the fluorescence nor magnetic signal of the nanoprobe can be detected. In the presence of AA, a redox reaction occurred between MnO2 nanosheet and AA resulting in the generation of magnetic resonance imaging (MRI) response Mn2+ and decomposing of MnO2 nanosheet structure, thus leading to the recovery of CDs fluorescence. The detection limit of the AA was determined to be 2.89⯵M with a linear range of 0-80⯵M in fluorescence mode, and detection limit of 0.776⯵M with a linear range of 0-80⯵M in MRI mode when used transverse relaxation rate as signal. Furthermore, the developed fluorometric/magnetic bi-functional nanoprobe showed good biocompatibility, high response rate, high selectivity towards AA and could be used to analyses AA in real samples. Moreover, in vivo imaging of AA in mice was achieved in magnetic mode. The fluorometric/magnetic bi-function sensor for AA detection was introduced, which provided a novel strategy for sensor design based on CDs.
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Ácido Ascórbico/análise , Corantes Fluorescentes/química , Imageamento por Ressonância Magnética/métodos , Compostos de Manganês/química , Óxidos/química , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Animais , Ácido Ascórbico/química , Ácido Ascórbico/metabolismo , Fluorescência , Corantes Fluorescentes/toxicidade , Limite de Detecção , Fenômenos Magnéticos , Masculino , Camundongos Endogâmicos BALB C , Oxirredução , Óxidos/toxicidade , Pontos Quânticos/toxicidadeRESUMO
OBJECTIVE: To explore the clinical effect of laparoscopic exploration in the diagnosis and treatment of abdominal open trauma. METHODS: Patients with abdominal open trauma admitted to the First Affiliated Hospital of Dalian Medical University from August to December in 2018 were enrolled. According to different exploration methods, 11 patients undergoing laparoscopic exploration were grouped into laparoscopy group and 20 patients undergoing exploratory laparotomy were grouped into laparotomy group. The operation time, the length of hospital stay, cases without abdominal visceral injury, postoperative exhaustion time, cases with complications and incision length were compared between the two groups. RESULTS: All the 31 patients were experienced with knife stab wound, with 26 males and 5 females, and the age was (33.39±11.47) years old. Compared with the laparotomy group, the length of hospital stay was significantly shorted in the laparoscopy group (days: 6.64±2.94 vs. 11.65±5.62), the postoperative exhaustion time was significantly decreased (hours: 40.36±29.04 vs. 75.60±42.84), the cases with complication was significantly decreased (case: 1 vs. 9), the incision length was significantly shorted (cm: 5.50±5.14 vs. 16.95±5.28), all of which results had statistical significance (all P < 0.05). The operation time of laparoscopy group was shorter than that of laparotomy group (hours: 2.18±0.87 vs. 2.61 ±1.28), but without significant difference (P > 0.05). Confirmed by surgical exploration, 5 patients had no abdominal visceral injury, with 3 in the laparoscopy group and 2 in the laparotomy group, and the result had no significant difference between the two groups (P > 0.05). CONCLUSIONS: For patients with abdominal open trauma, laparoscopic exploration is helpful for diagnosis as quickly as possible, with less trauma and reduction of complications incidence, and is conducive to postoperative rehabilitation.
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Traumatismos Abdominais/diagnóstico , Traumatismos Abdominais/terapia , Laparoscopia , Laparotomia , Adulto , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Complicações Pós-Operatórias/epidemiologia , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
In this study, silver decorated graphene oxide (Ag/GO) composite was fabricated through a reduction process in the presence of potassium borohydride solution. Subsequently, physicochemical properties of the resulting Ag/GO composite were studied by scanning electron microscope, X-ray diffraction, Raman spectra, Fourier transformation infrared spectroscopy and UV-visible diffuse reflectance spectrum. Results indicated that Ag species existed in the form of Ag0, which greatly facilitated the visible light absorbance ability. Furthermore, the performance of Ag/GO was evaluated by PC inactiviation of Escherichia coli under Xenon lamp illumination. It was found that Ag/GO sample could kill the Escherichia coli within 60 min illumination by the non-selective attack of â OH radicals. This study provides a novel and facile strategy to fabricate high-efficient catalyst to kill the bacteria in drinking water treatment.
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Escherichia coli , Grafite , Prata , Catálise , Nanocompostos , ÓxidosRESUMO
In the present study, silver phosphate/graphene oxide (Ag3PO4/GO) composite was synthesized by ultrasound-precipitation processes. Afterwards, physicochemical properties of the resulting samples were studied through scanning electron microscope, transmission electron microscope, X-ray diffraction, N2 adsorption/desorption, UV-vis diffuse reflectance spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, surface photovoltage spectroscopy and photoelectrochemical measurements. Results indicated that spherical Ag3PO4 displayed an average diameter of 150 nm and body-centered cubic crystal phase, which was integrated with GO. In addition, the visible light absorbance, charge separation efficiency and lifetime of Ag3PO4 were significantly improved by integration with GO. In addition, Ag3PO4/GO composite was applied to decompose tetrabromosphenol A (TBBPA) in water body. It was found that TBBPA could be completely decomposed within 60 min illumination. Furthermore, several scavenger experiments were conducted to distinguish the contribution of reactive species to the photoctalytic efficiency. Moreover, the enhanced visible light mechanism of Ag3PO4/GO was proposed and discussed. Eventually, several PC decomposition pathways of TBBPA were identified including directly debromination and oxidation, and subsequently further oxidation and hydroxylation processes.
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It is challenging to design a photocatalyst with high-efficiency light absorption, charge separation and even high-efficiency charge transfer. Here, we report a demonstration by utilizing a three-dimensional multilayered core-shell nanowire array (rGO-ITO@BiVO4) as the composite photocatalyst. The core-shell structure can shorten the length of charge transfer and enhance light absorption through multireflection. RGO with defects can work as the charge transfer medium to improve the hole injection from semiconductor to electrolyte. Associated with the above effects, the Co-pi electrocatalyst modified rGO-ITO@BiVO4 photocatalyst yields a photocurrent of about 6.0 mA cm-2 at 0.6 V vs. Ag/AgCl. Transient-state surface photovoltage measurement shows that the rGO layer can prolong the lifetime of the photogenerated holes through π-π interactions, so that more holes can participate in the water oxidation reaction.
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Now, chronic psychological stress (CPS) related diseases are increasing. Many CPS patients have gastrointestinal complaints, immune suppression, and immune imbalance. Increasing evidence is indicating that acupuncture (AP) at the Zusanli point (ST36) can alleviate functional gastrointestinal disorders (FGID), immune suppression, and immune imbalance. However, few studies have investigated the potential mechanisms. In this study, CPS rat models were established, and electroacupuncture (EA) at ST36 was done for CPS rats. Daily food intake, weight, intestinal sensitivity, the morphology of interstitial cell of Cajal (ICC) in the small intestine, and serum indexes were measured. The study found that, in CPS rats, EA at ST36 could improve food intake, weight, visceral hypersensitivity, and immunity; in CPS rats, in small intestine, the morphology of ICCs was abnormal and the number was decreased, which may be part causes of gastrointestinal motility dysfunction. EA at ST36 showed useful therapeutic effects. The mechanisms may be partially related to its repairing effects on ICCs damages; in CPS rats, there were immune suppression and immune imbalance, which may be part causes of visceral hypersensitivity. EA at ST36 showed useful therapeutic effects. The mechanisms may be partially related to its regulation on immunity.
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OBJECTIVE: To observe the apoptosis of interstitial cells of Cajal in deep muscular layer (ICC-DMP) of small intestine in rats with multiple organ dysfunction syndrome (MODS) as a result of bacterial peritonitis, and the expression of c-kit (an ICC phenotype marker) and Bax/Bcl-2, in order to investigate the mechanism of gastrointestinal motility dysfunction in MODS. METHODS: According to the random number table, 40 Wistar rats were randomly divided into two groups: control group (n=20) and MODS group (n=20). The MODS model in rats was reproduced by intraperitoneal injection of 8×10(8) cfu/mL Escherichia coli suspension 1 mL, and the control group was given the same amount of normal saline. After 24 hours, the upper small intestine was harvested for examination. Ultrastructure of ICC-DMP was observed using electron microscope. The network structure of ICC-DMP and the expression of c-kit and Bax/Bcl-2 were observed and determined with immunofluorescence and laser scanning confocal microscope. RESULTS: Macroscopic observation revealed that the gastrointestinal motility of rats was normal in the control group. Compared with the control group, gastro intestine was significantly expanded with parulytic ileus in MODS group. It was shown by transmission electron microscopy that intermediate filament structure of ICC-DMP was clear without swelling of mitochondria; chromatin distributed uniformly with small amounts of heterochromatin aggregated in perinuclear. Compared with the control group, intermediate filament structure of ICC-DMP was fuzzy, and mitochondria were swollen obviously in MODS group; chromatin was assembled in nucleus centre. It was shown by laser scanning confocal microscope that the network structure of ICC-DMP was clear, the expression of c-kit and Bcl-2 was strongly and overlapping; the expression of Bax was weak and scatter distributed. Compared with control group, ICC-DMP quantity in MODS group was significantly reduced (cells/HP: 15.80±2.30 vs. 25.70±3.97, t=6.819, P=0.000 ), and ICC network was incomplete. The expression of c-kit and Bcl-2 was significantly decreased as compared with control group [ c-kit (fluorescence intensity): 129.56±36.90 vs. 307.23±40.07, t=10.314, P=0.000; Bcl-2 (fluorescence intensity): 103.23±25.19 vs. 378.92±43.79, t=17.259, P=0.000], whereas, the expression of Bax was significantly increased (fluorescence intensity: 270.94±36.98 vs. 92.57±20.92, t=-13.277, P=0.000 ). CONCLUSIONS: The mechanism of gastrointestinal motility dysfunction in MODS maybe closely related to ultrastructural damage of ICC-DMP, changes of c-kit phenotypic and activation of mitochondrial apoptosis pathway.
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Apoptose , Células Intersticiais de Cajal , Intestino Delgado , Insuficiência de Múltiplos Órgãos , Animais , Motilidade Gastrointestinal , Mitocôndrias , Músculo Liso , Proteínas Proto-Oncogênicas c-kit , Ratos , Ratos WistarRESUMO
OBJECTIVE: To observe the morphological changes in enteric nerve system (ENS) of rats with multiple organ dysfunction syndrome (MODS) treated by Dachengqi Decoction (, DCQD). METHODS: Fifty Wistar rats were randomly assigned to the control group, MODS model group and DCQD treated group. The rats in MODS model group and DCQD treated group were injected Escherichia coli (E. coli) suspension into abdominal cavity under sterile condition. The DCQD treated group was gavaged with DCQD 2 days before the E. coli suspension was injected. Twenty-four hours after injection, the proximal segment of intestine was resected and studied by immunohistofluorescence using vesicular acetylcholine transporter, vasoactive intestinal polypeptide (VIP), substance P (SP) and neuronal nitric oxide synthase (nNOS) antibodies. The whole-mount preparations were observed by laser scanning confocal microscope to detect the changes of quantity and fluorescence integral optical density (IOD) value of intestine enteric nerves. RESULTS: Compared with the control group, the quantity and IOD value of acetylcholine (ACh), VIP, SP and nitric oxide (NO) nerves of intestine in the MODS group were significantly decreased (P<0.01), and the network of enteric nerves was remarkably disrupted. Compared with the MODS group, the quantity and fluorescence IOD value of ACh, VIP, SP and NO nerves in the DCQD group were significantly increased (P<0.01), and the network of enteric nerves was remarkably recovered. CONCLUSION: DCQD can protect and repair damage in the network of ACh, SP, NO and VIP nerves in rats with MODS, which may be one of mechanisms involved in promoting gastrointestinal motility by DCQD.
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Sistema Nervoso Entérico/efeitos dos fármacos , Insuficiência de Múltiplos Órgãos/patologia , Extratos Vegetais/farmacologia , Animais , Sistema Nervoso Entérico/patologia , Feminino , Masculino , Ratos , Ratos WistarRESUMO
OBJECTIVE: To discuss the mechanism of promotion of gastrointestinal motility during multiple organ dysfunction syndrome (MODS) by Dachengqi decoction, by examining the expression of Bcl-2, Bax of mitochondrial pathway, and nuclear factor-ΚB (NF-ΚB) in smooth muscle of the small intestinal in rats. METHODS: According to the random number table, 100 healthy adult Wistar rats were divided into three groups: control group with 20 rats, model group with 40 rats, and Dachengqi decoction group with 40 rats. Rat model of MODS was reproduced by bacterial peritonitis induced by an injection of 1 mL Escherichia coli suspension (8×10(8) cfu/mL) into peritoneal cavity. The rats in control group were given 1 mL normal saline intraperitoneally. The rats in Dachengqi decoction group were given 10 mL/kg Dachengqi decoction by gavage, twice a day, before inoculation of the bacterial suspension. Twenty-four hours after modelling, rats in all groups were sacrificed by cervical vertebra luxation, and the upper small intestine was harvested to detect the protein expressions of Bcl-2, Bax, and NF-ΚB in smooth muscle tissue using immunohistochemical staining. RESULTS: In the control group, a large amount of Bcl-2 protein was expressed and it was distributed uniformly in small intestinal smooth muscle. On the other hand, a small amount of Bax and NF-ΚB protein was expressed, and they were also distributed uniformly. Compared with the control group, Bcl-2 protein was distributed only sparsely, and it was scattered in intestinal smooth muscle in blocks in the model group. The expression of Bcl-2 protein was obviously down-regulated [integral optical density (A) value: 7 115.3±1 797.2 vs. 22 085.5±4 892.2, P < 0.05], and this phenomenon was more prominent in circular muscle layer. Bax and NF-ΚB were densely distributed, and their expressions were upgraded obviously [Bax (A value): 33 802.6±5 778.0 vs. 7 984.4±1 804.5, NF-ΚB (A value): 2 465.9±664.8 vs. 1 572.6±256.0, both P < 0.05]. This phenomenon was more outstanding in circular muscle layer. Compared with that of the model group, the expression of Bcl-2 protein was stronger obviously in intestinal smooth muscle in Dachengqi decoction group (A value: 12 458.6±2 491.1 vs. 7 115.3±1 797.2, P < 0.05). The expressions of Bax and NF-ΚB were down-regulated obviously [Bax (A value): 12 529.2±2 018.5 vs. 33 802.6±5 778.0, NF-ΚB (A value): 1 843.1±373.6 vs. 2 465.9±664.8, both P < 0.05], and the change was more obvious in circular muscle layer. CONCLUSIONS: Dachengqi decoction may promote recovery of gastrointestinal motility through an increase of Bcl-2 expression in nuclear membrane, thus preventing translocation of Bax to mitochondrion, thereby reduces mitochondrial damage in MODS.
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Intestinos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Insuficiência de Múltiplos Órgãos/tratamento farmacológico , Músculo Liso/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Animais , Regulação para Baixo , Medicamentos de Ervas Chinesas/uso terapêutico , NF-kappa B , Proteínas Proto-Oncogênicas c-bcl-2 , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Proteína X Associada a bcl-2RESUMO
In this work, we have successfully constructed phosphate bridges in a TiO2-Fe2O3 nanocomposite using wet-chemical processes. Based on FTIR, XPS and TEM measurements it is confirmed that phosphate groups form bridges that effectively connect TiO2 and α-Fe2O3. From steady-state surface photovoltage spectra (SS-SPS) and transient-state surface photovoltage (TS-SPV) measurements in N2, it is clearly demonstrated that the separation and lifetime of the photogenerated charge carriers in the TiO2-Fe2O3 nanocomposite are greatly enhanced by the introduction of the phosphate bridges. As a consequence, the visible light photocatalytic activity in water reduction by methanol and the photoelectrochemical water oxidation were obviously improved after phosphate bridging. It is concluded mainly on the basis of ultra-low-temperature EPR signals, EIS spectra, and the normalized photocurrent action spectra that the photogenerated electrons of α-Fe2O3 under irradiation with visible light would transfer to TiO2 in the nanocomposite, and the built phosphate bridges are favorable for charge transportation, leading to the greatly-increased separation and lifetime of visible-light excited charge carriers. This work provides a feasible route to improve the photoactivity of other visible-response nanocomposites for water splitting.
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The increased surface-carried negative charge of BiVO4 after phosphate modification prolongs the photogenerated charge carrier lifetime and improves the separation by inducing the holes to transfer to the surface, leading to the obvious enhancement of visible light activities for PEC water oxidation.
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In this study, we investigate the morphologic changes of enteric nerve system (ENS) and the expression of neurotransmitters, acetylcholine (ACh), substance P (SP), vasoactive intestinal peptide (VIP) and nitric oxide synthase (NOS), in small bowel of rats undergoing multiple organ dysfunction syndrome (MODS). Undergoing MODS, fluorescence integral optical density (IOD) value of enteric nerve fibers were significantly decreased (P<0.05), and the network structure of ENS was destroyed. The expression of ACh, SP, VIP and NOS was inhibited, IOD value of the four neurotransmitters was significantly decreased (P<0.05). After intervention of DCQD, the fluorescence IOD value of enteric nerves were significantly increased (P<0.05), and the network structure of ENS was repaired. The expression of ACh, SP, VIP and NOS was recovered, fluorescence IOD value of the four neurotransmitters was significantly increased (P<0.05). In conclusion, the gastrointestinal motility disorders undergoing MODS may be closely related to the morphology destroy of ENS and down regulation of neurotransmitters (ACh, SP, VIP and NOS) expression. DCQD could promote gastrointestinal motility through protecting the morphology of ENS and up regulation of neurotransmitters (ACh, SP, VIP and NOS) expression.
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Wistar rats were randomly divided into control group, multiple organ dysfunction syndrome (MODS) group, and Da-Cheng-Qi decoction (DCQD) group. The network of enteric nerves-interstitial cells of Cajal- (ICC-) smooth muscle cells (SMC) in small intestine was observed using confocal laser scanning microscopy and transmission electron microscopy. The results showed that the numbers of cholinergic/nitriergic nerves, and the deep muscular plexus of ICC (ICC-DMP) and connexin43 (Cx43) in small intestine with MODS were significantly decreased. The network integrity of enteric nerves-ICC-SMC was disrupted. The ultrastructures of ICC-DMP, enteric nerves, and SMC were severely damaged. After treatment with DCQD, the damages were repaired and the network integrity of enteric nerves ICC-SMC was significantly recovered. In conclusion, the pathogenesis of gastrointestinal motility dysfunction in MODS in part may be due to the damages to enteric nerves-ICC-SMC network and gap junctions. The therapeutic mechanism of DCQD in part may be that it could repair the damages and maintain the integrity of enteric nerves ICC-SMC network.