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1.
J Colloid Interface Sci ; 660: 961-973, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38281477

RESUMO

High-performance photocatalysts for catalytic reduction of CO2 are largely impeded by inefficient charge separation and surface activity. Reasonable design and efficient collaboration of multiple active sites are important for attaining high reactivity and product selectivity. Herein, Cu-Cu2O and Ag nanoparticles are confined as dual sites for assisting CO2 photoreduction to CH4 on TiO2. The introduction of Cu-Cu2O leads to an all-solid-state Z-scheme heterostructure on the TiO2 surface, which achieves efficient electron transfer to Cu2O and adsorption and activation of CO2. The confined nanometallic Ag further enhances the carrier's separation efficiency, promoting the conversion of activated CO2 molecules to •COOH and further conversion to CH4. Particularly, this strategy is highlighted on the TiO2 system for a photocatalytic reduction reaction of CO2 and H2O with a CH4 generation rate of 62.5 µmol∙g-1∙h-1 and an impressive selectivity of 97.49 %. This work provides new insights into developing robust catalysts through the artful design of synergistic catalytic sites for efficient photocatalytic CO2 conversion.

2.
J Colloid Interface Sci ; 606(Pt 2): 1477-1487, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34500152

RESUMO

A well-designed photocatalyst with excellent activity and selectivity is crucial for photocatalytic CO2 conversion and utilization. TiO2 is one of the most promising photocatalysts. However, its excessive surface oxidation potential and insufficient surface active sites inhibit its activity and photocatalytic CO2 reduction selectivity. In this work, highly dispersed Bi2Ti2O7 was introduced into defective TiO2 to adjust its oxidation potential and the generation of radicals, further inhibiting reverse reactions during the photocatalytic conversion of CO2. Moreover, an in situ topochemical reaction etching route was designed, which achieved defective surfaces, a contacted heterophase interface, and an efficient electron transfer path. The optimized heterophase photocatalyst exhibited 93.9% CH4 selectivity at a photocatalytic rate of 6.8 µmol·g-1·h-1, which was 7.9 times higher than that of P25. This work proposes a feasible approach to fabricating photocatalysts with well-designed band structures, highly dispersed heterophase interfaces, and sufficient surface active sites to effectively modulate the selectivity and activity of CO2 photoreduction by manipulating the reaction pathways.


Assuntos
Dióxido de Carbono , Radical Hidroxila , Catálise , Oxirredução , Titânio
4.
Curr Drug Metab ; 20(10): 799-803, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31608839

RESUMO

BACKGROUND: To investigate MiRNA-126 amounts in serum exosomes from allergic asthma patients as well as lung tissues of asthmatic mice, evaluating the expression of its target gene DNMT1 in mouse specimens. METHODS: MiRNA-126 amounts in serum exosomes from asthmatic patients were detected by real-time PCR. The mouse model of allergic asthma was established by OVA-sensitization, and allergic symptoms were recorded; serum IL-4 and sIgE level evaluation (ELISA), broncho alveolar lavage fluid (BALF) cell count and H&E staining were performed to assess airway inflammation. MiRNA-126 and DNMT1 levels in the lung of asthmatic and control mice were detected by real-time PCR; DNMT1 protein levels were detected by immunoblot. RESULTS: MiRNA-126 amounts in peripheral blood exosomes from patients with allergic asthma were significantly higher than that of healthy volunteers (P<0.05). The frequencies of scratching of both sides of the nose and sneezing were elevated within 10 min of excitation in asthmatic rats compared with controls. Meanwhile, OVA-sIgE and IL-4 levels were significantly higher in asthmatic animals than controls (P<0.05). In the asthma group, narrowed bronchial lumen and thickened wall were observed, and bronchial and peripheral vessels showed overt inflammatory cell infiltration. Eosinophil, neutrophil and mast cell amounts in the BALF of asthmatic mice were significantly higher than control values. Furthermore, lung miRNA-126 expression in asthmatic mice was significantly higher than that of controls. Finally, DNMT1 mRNA and protein levels were significantly lower in asthmatic animals compared with controls (P < 0.01). CONCLUSION: MiRNA-126 is highly expressed in serum exosomes from allergic asthma patients and lung tissues of asthmatic mice, suggesting that it may be involved in the pathogenesis of bronchial asthma.


Assuntos
Asma/sangue , Exossomos/genética , MicroRNAs/sangue , Animais , Asma/genética , Asma/metabolismo , Asma/patologia , Líquido da Lavagem Broncoalveolar/citologia , Contagem de Células , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Feminino , Humanos , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C
5.
Kaohsiung J Med Sci ; 33(4): 201-206, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28359408

RESUMO

Conventional laparoscopic cholecystectomy (CLC) is currently the standard of surgical procedure for gallstone disease. Robotic cholecystectomy (RC) has revolutionized the field of minimally invasive surgery; it is safe and ergonomic, but expensive. The aim of this study is to compare the medical resource utilization and clinical outcomes between the two procedures. This study was conducted retrospectively by assessing data of the clinical outcomes and medical resource of 78 patients receiving RC and 367 patients receiving CLC. We reviewed the data of operation times, length of hospital stay, hospital charges, outpatient department visits, outpatient department service charges, and postoperative complications, which were retrieved from the health information system (HIS) database in this hospital. Patients in both groups had similar demographic and clinical features. The RC group had longer length of hospital stay (p=0.056), significantly longer operation time (p=0.035), and much more hospital charges (p=0.001). The RC group, however, experienced less postoperative complication rates (average 3.8% vs. 20.4%, p=0.001). Conversion rate was 1.9% in the CLC group versus 0% in the RC group (p=0.611). Most complications were mild, and following the Clavien-Dindo classification, there were two cases (2.5%) Grade I for the RC group; 50 cases (13.6%) Grade I and 14 cases (3.81%) Grade II for the CLC group (p<0.001 and 0.001, respectively). Procedure-related complications of Grade IIIa status were encountered in nine patients (2.45%) in the CLC group and none in the RC group (p=0.002).The RC group consumed more medical resources in the index hospitalization; however, they experienced significantly less postoperative complications.


Assuntos
Colecistectomia Laparoscópica/estatística & dados numéricos , Recursos em Saúde/estatística & dados numéricos , Procedimentos Cirúrgicos Robóticos/estatística & dados numéricos , Colecistectomia Laparoscópica/efeitos adversos , Demografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/estatística & dados numéricos , Complicações Pós-Operatórias/etiologia , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Resultado do Tratamento
6.
Sci Rep ; 6: 24918, 2016 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-27114050

RESUMO

Surface defect of nanomaterials is an important physical parameter which significantly influences their physical and chemical performances. In this work, high concentration of surface oxygen vancancies (SOVs) are successfully introduced on {001} facets exposed BiOBr nanosheets via a simple surface modification using polybasic carboxylic acids. The chelation interaction between carboxylic acid anions and Bi(3+) results in the weakness of Bi-O bond of BiOBr. Afterwards, under visible-light irradiation, the oxygen atoms would absorb the photo-energy and then be released from the surface of BiOBr, leaving SOVs. The electron spin resonance (ESR), high-resolution transmission electron microscopy (HRTEM), and UV-vis diffuse reflectance spectra (DRS) measurements confirm the existence of SOVs. The SOVs can enhance the absorption in visible light region and improve the separation efficiency of photo-generated charges. Hence, the transformation rate of adsorbed O2 on the as-prepared BiOBr with SOVs to superoxide anion radicals (•O2(-)) and the photocatalytic activity are greatly enhanced. Based on the modification by several carboxylic acids and the photocatalytic results, we propose that carboxylic acids with natural bond orbital (NBO) electrostatic charges absolute values greater than 0.830 are effective in modifying BiOBr.

7.
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.

8.
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.

9.
PLoS One ; 4(2): e4450, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19214221

RESUMO

BACKGROUND: Phosphatase of regenerating liver-3 (PRL-3) is a member of the novel phosphatases of regenerating liver family, characterized by one protein tyrosine phosphatase active domain and a C-terminal prenylation (CCVM) motif. Though widely proposed to facilitate metastasis in many cancer types, PRL-3's cellular localization and the function of its CCVM motif in metastatic process remain unknown. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, a series of Myc tagged PRL-3 wild type or mutant plasmids were expressed in B16F1 melanoma cells to investigate the relationship between PRL-3's cellular localization and metastasis. With immuno-fluorescence microcopy and cell adhesion/migration assay in vitro, and an experimental passive metastasis model in vivo, we found that CCVM motif is critical for the localization of PRL-3 on cell plasma membrane and the lung metastasis of melanoma. In particular, Cystine170 is the key site for prenylation in this process. CONCLUSIONS/SIGNIFICANCE: These results suggest that cellular localization of PRL-3 is highly correlated with its function in tumor metastasis, and inhibition of PRL-3 prenylation might be a new approach to cancer therapy.


Assuntos
Membrana Celular/enzimologia , Melanoma , Metástase Neoplásica , Proteínas de Neoplasias/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Animais , Sequência de Bases , Adesão Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Humanos , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/genética , Prenilação , Proteínas Tirosina Fosfatases/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
10.
Mol Med ; 13(3-4): 151-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17592549

RESUMO

Phosphatase of regenerating liver-3 (PRL-3) has been proposed to promote the invasion of tumor cells to metastasis sites. However, the effect of PRL-3 on spontaneous metastasis has not been clearly demonstrated, and whether PRL-3 could become a new therapeutic target in malignant tumor is still unknown. In this study, we used PRL-3 siRNA as a molecular medicine to specifically reduce the expression of PRL-3 in B16-BL6 cells, a highly metastatic melanoma cell line. In vitro, PRL-3 siRNA significantly inhibited cell adhesion and migration, but had no effect on cell proliferation. In the spontaneous metastatic tumor model in vivo, PRL-3 siRNA treatment remarkably inhibited the proliferation of primary tumor, prevented tumor cells from invading the draining lymph nodes, and prolonged the life span of mice. Therefore, our results indicate that PRL-3 plays a critical role in promoting the whole process of spontaneous metastasis and tumor growth initiation, and that inhibiting PRL-3 will improve malignant tumor therapy.


Assuntos
Proteínas Imediatamente Precoces/metabolismo , Melanoma Experimental/patologia , Melanoma Experimental/fisiopatologia , Metástase Neoplásica/prevenção & controle , Proteínas Tirosina Fosfatases/metabolismo , RNA Interferente Pequeno/farmacologia , Animais , Proteínas Imediatamente Precoces/genética , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Proteínas Tirosina Fosfatases/genética , Transplante Homólogo , Células Tumorais Cultivadas
11.
Biochem Biophys Res Commun ; 333(4): 1269-75, 2005 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-15979576

RESUMO

In this study, we report the role of integrin alpha(5) in promoting melanoma metastasis. The alpha(5) expression was remarkably elevated in highly metastatic B16F10 melanoma cells compared to lowly metastatic B16F1 cells, whereas no significant changes were detected in those of integrin alpha(4), alpha(v), and beta(1) subunits. Neutralization of alpha(5) with anti-alpha(5) antibody significantly suppressed the potential of B16F10 cells for pulmonary metastasis in mice and inhibited cell adhesion or spreading to fibronectin in vitro. Furthermore, loss of the interaction between alpha(5) and fibronectin diminished cell survival and induced apoptosis in B16F10 cells. Above results provide clear evidence that integrin alpha(5) is positively correlated with melanoma metastasis and might be an anti-melanoma target.


Assuntos
Biomarcadores Tumorais/metabolismo , Fibronectinas/metabolismo , Integrina alfa5/metabolismo , Melanoma/metabolismo , Melanoma/secundário , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Melanoma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Mapeamento de Interação de Proteínas
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