Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Am Chem Soc ; 140(37): 11705-11715, 2018 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-30110545

RESUMO

Despite the recent surge of interest in inorganic lead halide perovskite nanocrystals, there are still significant gaps in their stability disturbance and the understanding of their destabilization, assembly, and growth processes. Here, we discover that polar solvent molecules can induce the lattice distortion of ligand-stabilized cubic CsPbI3, leading to the phase transition into orthorhombic phase, which is unfavorable for photovoltaic applications. Such lattice distortion triggers the dipole moment on CsPbI3 nanocubes, which subsequently initiates the hierarchical self-assembly of CsPbI3 nanocubes into single-crystalline nanowires. The systematic investigations and in situ monitoring on the kinetics of the self-assembly process disclose that the more amount or the stronger polarity of solvent can induce the more rapid self-assembly and phase transition. These results not only elucidate the destabilization mechanism of cubic CsPbI3 nanocrystals, but also open up opportunities to synthesize and store cubic CsPbI3 for their practical applications in photovoltaics and optoelectronics.

2.
Dis Esophagus ; 30(1): 1-7, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-26918692

RESUMO

Esophageal cancer (EC) is one of the most common cancers in China. The purpose of this study was to investigate the updated incidence rates and risk factors of EC in Nan'ao Island, where the EC incidence rate was chronically the highest in southern China. To calculate the annual incidence rate, data on 338 EC cases from Nan'ao Cancer Registry system diagnosed during 2005-2011 were collected. A case-control study was conducted to explore the EC risk factors. One hundred twenty-five alive EC patients diagnosed during 2005-2011 and 250 controls were enrolled into the case-control study. A pre-test questionnaire on demography, dietary factors, drinking water treatment, and behavioral factors was applied to collect information of all participants. The average EC incidence rates during 2005-2011 were 66.09/105, 94.62/105, 36.83/105 for both genders, males and females, respectively, in Nan'ao Island. The EC incidence rate in males was 2.40- to 4.55-fold higher than that in females in the period from 2006 to 2011 (P < 0.05). Considering the onset age, males tend to be much younger than females and reached peak incidence rate at a younger age (P < 0.05). Drinking water treatment by filter (odds ratio [OR] = 0.28, 95% confidence interval [95% CI] = 0.13-0.58) and fruit consumption (OR = 0.55, 95% CI = 0.32-0.94) reduced the risk for EC. On the contrary, the pickled vegetables consumption (OR = 2.64, 95% CI = 1.46-4.76) and liquor drinking (OR = 2.32, 95% CI = 1.21-4.44) increased the risk for EC. These results may be of importance for future research on EC etiology and prevention strategies.


Assuntos
Adenocarcinoma/epidemiologia , Consumo de Bebidas Alcoólicas/epidemiologia , Carcinoma de Células Escamosas/epidemiologia , Dieta/estatística & dados numéricos , Neoplasias Esofágicas/epidemiologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , China/epidemiologia , Água Potável , Feminino , Conservação de Alimentos , Frutas , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Proteção , Fatores de Risco , Distribuição por Sexo , Verduras
3.
Biosens Bioelectron ; 26(5): 1975-9, 2011 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20934864

RESUMO

This study focuses on the preparation of a new type of Prussian Blue/polyaniline (PB/PANI)-modified electrode as oxygen reduction cathode, and its availability in microbial fuel cell (MFC) for biological power generation. The PB/PANI-modified electrode was prepared by electrochemical and chemical methods, both of which exhibited good electrocatalytical reactivity for oxygen reduction in acidic electrolyte. The MFC with PB/PANI-modified cathode aerated by either oxygen or air was shown to yield a maximum power density being the same with that of the MFC with liquid-state ferricyanide cathode, and have an excellent duration as indicated by stable cathode potential for more than eight operating circles. This study suggests a promising potential to utilize this novel electrode as an effective alternative to platinum for oxygen reduction in MFC system without losing sustainability.


Assuntos
Compostos de Anilina/química , Bactérias Anaeróbias/fisiologia , Fontes de Energia Bioelétrica/microbiologia , Eletrodos/microbiologia , Ferrocianetos/química , Oxigênio/química , Desenho de Equipamento , Análise de Falha de Equipamento , Oxirredução
5.
Bioconjug Chem ; 19(3): 651-5, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18254583

RESUMO

Water-soluble gadofullerides exhibited high efficiency as magnetic resonance imaging (MRI) contrast agents. In this paper, we report the conjugation of the newly synthesized gadofulleride, Gd@C82O6(OH) 16(-)(NHCH2CH2COOH)8, with the antibody of green fluorescence protein (anti-GFP), as a model for "tumor targeted" imaging agents based on endohedral metallofullerenes. In this model system, the activity of the anti-GFP conjugate can be conveniently detected by green fluorescence protein (GFP), leading to in vitro experiments more direct and facile than those of tumor antibodies. Objective-type total internal reflection fluorescence microscopy revealed that each gadofulleride aggregate conjugated on average five anti-GFPs, and the activity of anti-GFPs was preserved after conjugation. In addition, the gadofulleride/antibody conjugate exhibited higher water proton relaxivity (12.0 mM (-1) s (-1)) than the parent gadofulleride aggregate (8.1 mM (-1) s (-1)) in phosphate buffered saline at 0.35 T, as also confirmed by T1-weighted images of phantoms. These observations clearly indicate that the synthesized gadofulleride/antibody conjugate not only has targeting potential, but also exhibits higher efficiency as an MRI contrast agent.


Assuntos
Anticorpos/química , Meios de Contraste/síntese química , Gadolínio/química , Imagem por Ressonância Magnética/métodos , Biotina/química , Fenômenos Químicos , Físico-Química , Proteínas de Fluorescência Verde/imunologia , Indicadores e Reagentes , Conformação Molecular , Peso Molecular , Soroalbumina Bovina/química , Solubilidade , Espectrometria de Fluorescência , Estreptavidina/química , Água
6.
J Biol Chem ; 283(10): 6261-71, 2008 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-18089556

RESUMO

Dehydration-responsive element-binding proteins (DREBs) and ethylene-responsive element (ERE) binding factors are two major subfamilies of the AP2/ethylene-responsive element-binding protein family and play crucial roles in the regulation of abiotic- and biotic-stress responses, respectively. In the present work, we have reported a previously identified DREB-like factor, TINY, that was involved in both abiotic- and biotic-stress signaling pathways. TINY was capable of binding to both DRE and ERE with similar affinity and could activate the expression of reporter genes driven by either of these two elements in tobacco cells. The 15th amino acid in the APETALA2 (AP2)/ethylene-responsive element-binding factor domain was demonstrated to be essential for its specific binding to ERE, whereas the 14th and 19th amino acids were responsible for the binding to DRE. The expression of TINY was greatly activated by drought, cold, ethylene, and slightly by methyl jasmonate. Additionally, overexpression of TINY in Arabidopsis resulted in elevated expressions of both the DRE- and the ERE-containing genes. Moreover, the expression of DRE-regulated genes, such as COR6.6 and ERD10, was up-regulated upon ethylene treatment, and the expression of ERE-regulated genes, such as HLS1, was also increased by cold stress, when the expression of TINY was being induced. These results strongly suggested that TINY might play a role in the cross-talk between abiotic- and biotic-stress-responsive gene expressions by connecting the DRE- and ERE-mediated signaling pathways. The results herein might promote the understanding of the mechanisms of specific DNA recognition and gene expression regulation by DREBs.


Assuntos
Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Elementos de Resposta/fisiologia , Transdução de Sinais/fisiologia , Acetatos/farmacologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Temperatura Baixa , Ciclopentanos/farmacologia , Desidratação/genética , Desidratação/metabolismo , Desastres , Etilenos/metabolismo , Etilenos/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Oxilipinas/farmacologia , Reguladores de Crescimento de Planta/metabolismo , Reguladores de Crescimento de Planta/farmacologia , Estrutura Terciária de Proteína/fisiologia , Transdução de Sinais/efeitos dos fármacos
7.
Zhonghua Zhong Liu Za Zhi ; 29(3): 232-5, 2007 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-17649645

RESUMO

OBJECTIVE: To investigate the efficacy of different interventional therapies for primary hepatic cell cancer (HCC). METHODS: 1126 HCC patients before or after hepatectomy were treated by different kinds of interventional therapies: transcatheter arterial chemoembolization (TACE), TACE and radio-frequency ablation (RFA), Chinese traditional medicine and biotherapy after TACE or the transcatheter arterial infusion (TAI). The results of liver function, alpha-fetoprotein, imaging, color-ultrasonography and survival rate were reviewed. RESULTS: 874 patients were followed up for 2 to 63 months. The overall 1-, 3-, 5-year survival rate was 67.8% , 28.7% and 18.8%, respectively. The 1-, 3-, 5-year survival rate of patients who received TACE before hepatectomy was 74.7%, 41.4% and 36.9% ; after hepatectomy 78.9%, 40.4% and 37.5%, respectively. The response rate ( PR + NC) of TACE and RFA was 93.4%, and the 1-, 3-year survival rate was 74.5% and 36.8%, respectively, after TACE and RFA. The response rate (PR + NC) of TACE was 83.2% with 1-, 3-, 5-year survival rate of 69.3%, 21.7%, 8.4% after TACE, respectively. The response rate (PR + NC) of TAI was 27.5% with 1-, 2-year survival rate of 11. 6% and 0 after TAI. The Child grade of liver function, color-ultrasonography and alpha-fetoprotein of TACE + RFA group, TACE and TAI were compared. There was no significant difference between each above mentioned index among TACE, RFA or TACE groups. CONCLUSION: Compared with other modalities, transcatheter arterial chemoembolization (TACE) before or after hepatectomy is more effective than other interventional therapies for primary hepatocellular cancer, whereas, if combined with radiofrequency ablation (TAI), it is much more effective than TACE alone.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/terapia , Adulto , Idoso , Carcinoma Hepatocelular/cirurgia , Ablação por Cateter , Terapia Combinada , Feminino , Seguimentos , Hepatectomia , Humanos , Infusões Intra-Arteriais , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Resultado do Tratamento , alfa-Fetoproteínas/metabolismo
8.
World J Gastroenterol ; 12(31): 5060-3, 2006 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-16937507

RESUMO

AIM: To verify the effect of combined interventional therapy for hepatocellular carcinoma (HCC). METHODS: The clinical data of 1126 HCC patients who received combined interventional therapy for transcatheter arterial chemoembolization (TACE) before or after hepatectomy, TACE and radio-frequency ablation (RFA), Chinese medicine treatment and biotherapy after TACE or transcatheter arterial infusion (TAI), were reviewed according to the results of their liver function, alpha-fetoprotein, image data, color-ultrasonography finding and survival rate. RESULTS: A total of 874 patients were followed up for a period of 2 to 63 mo. The overall 1-, 3- and 5- year survival rates were 67.8%, 28.7% and 18.8% respectively. The 1- 3- and 5- year survival rates of patients who received TACE were 74.7%, 41.4%, 36.9% before hepatectomy and 78.9%, 40.4%, 37.5% after hepatectomy. The effective rate (PR + NC) after TACE and RFA was 93.4%, the 1- and 3- year survival rates were 74.5% and 36.8% after TACE and RFA. The effective rate of PR + NC after TACE was 83.2%. The 1-, 3- and 5- year survival rates were 69.3%, 21.7%, 8.4% after TACE. The effective rate of PR + NC after TAI was 27.5%, the 1- and 2- year survival rates were 11.6% and 0% after TAI. The liver function, color-ultrasonography finding and alpha-fetoprotein after TACE + RFA, TACE and TAI were compared. There was no significant difference in each index between TACE and RFA or TACE as well as in liver function between TACE and RFA or between TACE and TAI. CONCLUSION: The therapeutic effectiveness of TACE before or after hepatectomy is most significant, while the effect of TACE and RFA is better than that of TACE, and the effect of TAI is minimal.


Assuntos
Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Adulto , Idoso , Quimioembolização Terapêutica/métodos , Terapia Combinada , Feminino , Seguimentos , Humanos , Rim/metabolismo , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo
9.
Ultramicroscopy ; 105(1-4): 129-36, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16095837

RESUMO

The adsorption of plasma protein fibrinogen on the self-assembled monolayers (SAMs) of n-hexadecyl mercaptan and citrate was investigated with atomic force microscopy (AFM). On the basis of the preparation of these two flat SAMs on Au(111), high-resolution AFM images of bovine fibrinogen were obtained with different protein concentrations. The results indicated that the surface chemical composition significantly affected the adsorption behavior of fibrinogen. Since fibrinogen plays a key role in the regulation of both haemostasis and thrombosis, high-resolution AFM imaging on SAMs is expected to be an effective approach to study the haemocompatibility of materials with different surface chemistry.


Assuntos
Fibrinogênio/farmacocinética , Microscopia de Força Atômica , Prata/química , Adsorção , Animais , Bovinos , Propriedades de Superfície
10.
J Nanosci Nanotechnol ; 4(6): 561-4, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15518386

RESUMO

Self-assembled monolayer of a double-stranded DNA, which was formed by a 20-nt 5'-thiol-modified oligonucleotide at the interface of Au(111)/solution, has been imaged and studied with electrochemical scanning tunneling microscopy (ECSTM). The results showed that the preferred directions of the adsorbed DNA were <110> and <112>. The measured width of the DNA stripes was 0.95 +/- 0.02 nm, which was consistent with the width of dsDNA base pairs. The contour of DNA in the STM image consisted of a series of blobs, which were due to the anchoring of the bases to the substrate along the dsDNA chain. The imaging of a large-scale array of DNA lying flat on the substrate offers a convenient method for the further application of high-resolution STM to the study of the interaction between DNA and a variety of molecules.


Assuntos
DNA/ultraestrutura , Eletroquímica/métodos , Ouro/química , Microscopia de Tunelamento/métodos , Nanotecnologia/métodos , Composição de Bases , DNA/química , Conformação de Ácido Nucleico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA