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1.
Phys Chem Chem Phys ; 25(6): 4553-4562, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36722893

RESUMO

A Z-scheme BNO/BSO composite photocatalyst has been successfully prepared using an in situ solvothermal method. The phase component, microstructure and optical properties of the as-prepared samples were characterized using X-ray diffractometry, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, photoluminescence spectroscopy and other means. The photocatalytic performance of the BNO/BSO composite was evaluated via the degradation of the typical antibiotic tetracycline (TC) under hydrogen peroxide assistance and visible light irradiation. The "cata + H2O2 + vis" system shows the best photocatalytic activity, and its apparent rate constant reaches 0.03164 min-1, which is 4.9 times and 5.7 times that of the "cata + vis" system and the "cata + H2O2" system, respectively. Compared with pristine that of BSO alone, the reaction rate constant of the 15% BNO/BSO composite increases 1.8 times. The enhanced photocatalytic activity is attributed to the construction of a unique Z-scheme-type heterojunction, which effectively suppresses the recombination of electron-hole pairs. In addition, the addition of H2O2 promotes the generation of more active species. Moreover, a possible photocatalytic degradation mechanism is also further proposed.

2.
Tumour Biol ; 36(1): 371-4, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25263716

RESUMO

Genes coding for proteins involved in steroid hormone signaling have been identified as ovarian cancer risk-modifier candidates. AIB1 gene (amplified in breast cancer-1), an androgen receptor (AR) coactivator, expresses a polyglutamine (poly-Q) sequence within the carboxyl-terminal coding region. We hypothesized that genotypic variations in the androgen-signaling pathway promote aggressive epithelial ovarian cancer biology and sought to examine the effect of AIB1 poly-Q repeat length on ovarian cancer risk with a case-control study. The genotype analysis of the AIB1 poly-Q repeat was conducted in 3,000 epithelial ovarian cancer (EOC) cases and 3,000 healthy controls. When analyzed as a categorical variable with cutoff of <28 or <29, both of results showed significant asociations. Compared to those with the shorter (<29) AIB1 poly-Q repeat length, women in the category of longer (≥29) poly-Q repeats had a significantly 20 % increased EOC risk (odds ratio (OR) = 1.20; 95 % confidence interval (CI), 1.08-1.33; P = 5.88 × 10(-4)). When analyzed as a continuous covariate, women with longer average poly-Q repeat length had a significantly increased risk of developing EOC (OR = 1.05 for per poly-Q repeat; 95 % CI, 1.00-1.08; P = 0.013). The association was more stronger for per longer allele (OR = 1.07; 95 % CI, 1.01-1.12; P = 0.010). These results strongly suggest that there is a significant effect of AIB1 genetic variation on ovarian cancer risk, and AIB1 underlies the development of ovarian cancer.


Assuntos
Neoplasias Epiteliais e Glandulares/genética , Coativador 3 de Receptor Nuclear/genética , Neoplasias Ovarianas/genética , Peptídeos/genética , Adulto , Carcinoma Epitelial do Ovário , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Polimorfismo Genético , Risco , Sequências Repetidas Terminais
3.
Chemosphere ; 259: 127463, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32599388

RESUMO

To treat typical organic wastewater efficiently, a novel Fenton-like processes based on ZnO/CuO composite cathode induced by oxygen reduction reaction (ORR) electrocatalysis with enhanced electrocatalytic performance was established successfully. Electrochemical testing investigation indicated that the ZnO/CuO cathode possessed conspicuous redox peak and better conductivity than uncompounded electrodes. Additionally, the removal efficiency of methylene blue and its chemical oxygen demand (COD) reached 96.4% and 70.8% after 120 min, respectively. Next, the feasibility of the material in practical application was also discussed. Subsequently, electrocatalytic principle based on valence state changes of metal elements on the electrode surface were also studied by x-ray photoelectron spectroscopy (XPS). Redox reactions between the active species H2O2 and the species Cu+ promoting Fenton-like processes were deduced. Namely, the conversion of Cu(I) and Cu(II) on the electrode surface was accompanied by OH generation. The combination of ZnO and CuO improved the surface morphology, increasing the active site of ORR and the yield of H2O2, thus greatly enhanced the Fenton-like activity. Finally, the main intermediates were identified by Gas chromatography-mass spectrometer (GC-MS), and possible pathways for dye degradation were proposed. In short, the research of ZnO/CuO cathode provided great significance for heterogeneous Fenton-like degradation and also showed its application potential in water treatment and remediation.


Assuntos
Poluentes Químicos da Água/análise , Purificação da Água/métodos , Análise da Demanda Biológica de Oxigênio , Catálise , Cobre , Eletrodos , Peróxido de Hidrogênio/química , Azul de Metileno , Oxirredução , Oxigênio , Águas Residuárias/química , Óxido de Zinco
4.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 7): o1352, 2008 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-21202971

RESUMO

In the crystal structure of the title Schiff base, C(20)H(25)N(3)O(2), the salicylaldimine groups at each end of the mol-ecule are essentially planar and make a dihedral angle of 84.94 (3)° with each other. There are strong intra-molecular O-H⋯N hydrogen bonds and a weak inter-molecular N-H⋯O hydrogen bond.

5.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 12): m1486, 2008 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-21581110

RESUMO

In the title complex, [Co(C(15)H(14)NO)(2)], the Co(II) atom, situated on an inversion centre, is coordinated by two O and two N atoms from two symmetry-related bidentate Schiff base ligands in a slightly distorted square-planar geometry. The two phenolate rings form a dihedral angle of 10.53 (2)°.

6.
J Hazard Mater ; 318: 732-741, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27493012

RESUMO

The 3-dimensional hierarchical ZnO flower-like architectures have been synthesized in a Zn(Ac)2·2H2O-Na2SeO3-KBH4-pyridine solvothermal system at 100°C for 24h. The flower-like architecture is assembled from ZnO nanosheets with a thickness of ∼1.5nm, and the flower-like architecture specific surface area is 132m(2)/g. When the ZnO flower-like architecture is used as the adsorbent for acid fuschin (AF), malachite green (MG), basic fuchsin (BF), congo red (CR) and acid red (AR) in water, the adsorption capacities for AF, MG, BF, CR and AR are 7154.9, 2587.0, 1377.9, 85.0 and 38.0mg/g, respectively. Evidently, the as-obtained ZnO flower-like architectures show excellent adsorption performances for triphenylmethane dyes, and the adsorption capacity of 7154.9mg/g for AF is the highest of all adsorbents for dyes. The adsorption mechanism can be attributed to the electrostatic attraction and the formation of ion-association complex between triphenylmethane dyes and ZnO hierarchical flower-like architectures.

7.
IEEE Trans Med Imaging ; 24(2): 170-9, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15707243

RESUMO

Fan-beam collimators are designed to improve the system sensitivity and resolution for imaging small objects such as the human brain and breasts in single photon emission computed tomography (SPECT). Many reconstruction algorithms have been studied and applied to this geometry to deal with every kind of degradation factor. This paper presents a new reconstruction approach for SPECT with circular orbit, which demonstrated good performance in terms of both accuracy and efficiency. The new approach compensates for degradation factors including noise, scatter, attenuation, and spatially variant detector response. Its uniform attenuation approximation strategy avoids the additional transmission scan for the brain attenuation map, hence reducing the patient radiation dose and furthermore simplifying the imaging procedure. We evaluate and compare this new approach with the well-established ordered-subset expectation-maximization iterative method, using Monte Carlo simulations. We perform quantitative analysis with regional bias-variance, receiver operating characteristics, and Hotelling trace studies for both methods. The results demonstrate that our reconstruction strategy has comparable performance with a significant reduction of computing time.


Assuntos
Algoritmos , Encéfalo/diagnóstico por imagem , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Tomografia Computadorizada de Emissão de Fóton Único/instrumentação , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Inteligência Artificial , Humanos , Análise Numérica Assistida por Computador , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
IEEE Trans Nucl Sci ; 52(5 Pt 1): 1274-1280, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16575431

RESUMO

In the paper, we present a new hardware acceleration method to speedup the ordered-subsets expectation-maximization (OS-EM) algorithm for quantitative SPECT (single photon emission computed tomography) image reconstruction with varying focal-length fan-beam (VFF) collimation. By utilizing the geometrical symmetry of VFF point-spread function (PSF), compensation for object-specific attenuation and system-specific PSF are accelerated using currently available PC video/graphics card technologies. A ten-fold acceleration of quantitative SPECT reconstruction is achieved.

9.
ACS Appl Mater Interfaces ; 7(11): 6109-17, 2015 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-25734621

RESUMO

Crystal facet engineering of semiconductors has been proven to be an effective strategy to increase photocatalytic performances. However, the mechanism involved in the photocatalysis is not yet known. Herein, we report our success in that photocatalytic performances of the Cl(-) ion capped CoO octahedrons with exposed {111} facets were activated by a treatment using AgNO3 and NH3·H2O solutions. The clean CoO {111} facets were found to be highly reactivity faces. On the basis of the polar structure of the exposed {111} surfaces, a charge separation model between polar {111} surfaces is proposed. There is an internal electric field between polar {111} surfaces due to the spontaneous polarization. The internal electric field provides a driving force for charge separation. The reduction and oxidation reactions selectively take place on the positive and negative polar {111} surfaces. The charge separation model provides a clear insight into charge transfer in the semiconductor nanocrystals with high photocatalytic activities and offer guidance to design more effective photocatalysts, solar cells, photoelectrodes, and other photoelectronic devices.

10.
Med Oncol ; 31(7): 35, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24915899

RESUMO

We investigated the efficacy and safety of a new second-line chemotherapy of combining folinic acid, 5-fluorouracil and irinotecan (FOLFIRI) with both panitumumab and bevacizumab to treat patients with metastatic colorectal cancer (mCRC). Patients with mCRC and unsuccessful previous oxaliplatin-based chemotherapy were included in the study. The FOLFIRI arm was given FOLFIRI only. The FOLFIRI+PB arm was given panitumumab (3 mg/kg) and bevacizumab (3 mg/kg) plus FOLFIRI every other week. Between 2009 and 2013, 155 and 137 patients were included in the FOLFIRI arm and FOLFIRI+PB arm, respectively. The response rate was 40.1 % for FOLFIRI+PB arm versus 30.1 % for FOLFIRI arm. The disease-controlled rate in FOLFIRI+PB arm was improved to 62.2 from 50.2 % in FOLFIRI arm. The median overall survival was 13.9 months in FOLFIRI+PB arm as compared to 10.7 months in FOLFIRI arm. A series of adverse events were comparable between two arms, whereas some of the antibody therapy-associated toxicities were observed in FOLFIRI+PB arm. The new strategy of combining panitumumab and bevacizumab with FOLFIRI as second-line chemotherapy for patients with mCRC is safe and feasible.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Camptotecina/análogos & derivados , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bevacizumab , Camptotecina/uso terapêutico , Neoplasias Colorretais/mortalidade , Feminino , Fluoruracila/uso terapêutico , Humanos , Leucovorina/administração & dosagem , Leucovorina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Panitumumabe , Resultado do Tratamento , Adulto Jovem
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