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1.
Angew Chem Int Ed Engl ; 58(36): 12580-12584, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31310447

RESUMO

Chlorosilanes are versatile reagents in organic synthesis and material science. A mild pathway is now reported for the quantitative conversion of hydrosilanes to silyl chlorides under visible-light irradiation using neutral eosin Y as a hydrogen-atom-transfer photocatalyst and dichloromethane as a chlorinating agent. Stepwise chlorination of di- and trihydrosilanes was achieved in a highly selective fashion assisted by continuous-flow micro-tubing reactors. The ability to access silyl radicals using photocatalytic Si-H activation promoted by eosin Y offers new perspectives for the synthesis of valuable silicon reagents in a convenient and green manner.

2.
Chemotherapy ; 64(4): 177-186, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31935733

RESUMO

INTRODUCTION: This study aims to explore the relationship betweenextracellular histone and prostate cancer and its mechanism. METHODS: Migration of prostate cancer cells was detected by Transwell. Inflammatory factor expression was investigated by ELISA. Epithelial-mesenchymal transition and expression of NF-κB pathway-related proteins were investigated using Western blotting. RESULTS: Under the induction of extracellular histones, the migration rate of prostate cancer cells and the levels of IL-1ß, TNF-α, and IL-6 were notably enhanced. Then, expression of E-cadherin was significantly down-regulated, while levels of N-cadherin, vimentin, ß-catenin, Snail, p-p65 and p-IκBα were significantly up-regulated, which was reversed by PDTC (pyrrolidine dithiocarbamate). CONCLUSION: Extracellular histone significantly promotes the progression of prostate cancer cells via NF-κB pathway-mediated inflammatory responses, which may serve as a novel target for treating prostate cancer.


Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Histonas/farmacologia , NF-kappa B/metabolismo , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Humanos , Masculino , Inibidor de NF-kappaB alfa/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA/metabolismo , Regulação para Cima/efeitos dos fármacos
3.
J Am Chem Soc ; 140(44): 15099-15113, 2018 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-30362731

RESUMO

A recent experimental study reported a visible-light-mediated aerobic oxidative coupling reaction of phenol with alkynes that produces hydroxyl-functionalized aryl ketones using inexpensive CuCl as catalyst under mild conditions. Here we apply the complete active space self-consistent field (CASSCF) method and multistate second-order perturbation (MS-CASPT2) theory in combination with density functional theory (DFT) to systematically explore the entire photocatalytic reaction between phenol and phenylacetylene in acetonitrile solution in the presence of molecular oxygen and CuCl. Our main findings are as follows: (1) The visible-light-driven conversion of phenylacetylene to PhCCCu(I) occurs thermally because of efficient excited-state deactivation to the S0 state. (2) The single electron transfer from PhCCCu(I) to molecular oxygen that leads to the PhCCCu(II) cation takes place in the T1 state after an efficient S1 → T1 intersystem crossing. (3) During the initial oxidation of phenol, molecular oxygen prefers to attack the para position of the phenol radical intermediate to produce 1,4-benzoquinone, which further reacts with PhCCCu(II) to generate para-hydroxyl-substituted aryl ketones; this is the origin of the experimentally observed regioselectivity. (4) The C≡C bond of the phenylacetylene moiety is not activated by the triplet-state single electron transfer from PhCCCu(I) to molecular oxygen but is cleaved at a later stage, in the [2+2] cycloaddition between PhCCCu(II) and 1,4-benzoquinone. (5) The substrate phenol plays an active role in several hydrogen transfer and decarboxylation reactions; the barriers to these phenol-assisted reactions are lower than those for the corresponding direct or water-assisted reactions, which explains the experimental finding that adding water does not enhance the photocatalytic reaction yield. In summary, while supporting the general features of the experimentally proposed mechanism, our computational study provides detailed mechanistic insights that should be useful for understanding and further improving visible-light-induced copper-catalyzed coupling reactions.

4.
Phys Chem Chem Phys ; 20(23): 16138-16150, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29854994

RESUMO

Herein, we employed combined CASPT2 and B3LYP electronic structure methods in the framework of the quantum mechanics/molecular mechanics (QM/MM) approach to explore the ozonolysis of α-humulene and subsequent Criegee reactions with acids and water at the air-water/acetonitrile interface as a surrogate for atmospheric aqueous organic media. First, we found that the 1,3-cycloaddition reactions of ozone on α-humulene proceed concertedly and have small barriers (less than 2.5 kcal mol-1) at the QM(CASPT2)/MM level. Second, the five-membered ring cleavage reactions of the generated ozonides are rate-limiting steps and have considerable barriers (more than 10.0 kcal mol-1). These ring-opening reactions are also concerted and simultaneously lead to the cleavage of O-O and C-C bonds, producing sesquiterpene Criegee intermediates at the air-water/acetonitrile interface. Third, although these Criegee intermediates can react with water and acids near the air-water/acetonitrile boundary, the addition reactions with acids have smaller barriers, which range from 2.7 kcal mol-1 of R1-COOH to 5.6 kcal mol-1 of R7-COOH. In contrast, in water addition reactions, several different water-mediated reaction pathways have been disclosed. Their reaction barriers are found to decrease remarkably with an increase in the number of water molecules involved in the reactions. Finally, we found that in addition to low water concentration near the air-water/acetonitrile boundary, distinct reactivities of Criegee intermediates with acids and water play very important roles in the determination of the fates of the Criegee intermediates. Our present QM/MM study provides new mechanistic insights into ozonolysis and Criegee reactions at air-water/acetonitrile interfaces and gives important implications for new particle formation and secondary organic aerosol formation near the marine boundary.

5.
Biochim Biophys Acta Mol Basis Dis ; 1864(9 Pt B): 2769-2784, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29751081

RESUMO

Leukemia inhibitory factor receptor (LIFR) has been documented as a cancer promoter and to be present at high levels in various types of tumor tissues. In our search for molecules prognostic of colorectal cancer (CRC), we found high levels of LIFR in CRC tissue samples. Further analyses revealed that LIFR was indeed prognostic of CRC patient survival, and was associated with tumor size, lymphatic metastasis and stages. LIFR was found to promote tumor growth, metastasis and angiogenesis both in vitro and in vivo. High levels of LIFR in CRC facilitated proliferation and migration of endothelial cells, resulting in an increase in angiogenic activity. Moreover, interleukin 8 (IL-8) was found to play a role in the LIFR induced angiogenesis. IL-8 levels were correlated with LIFR levels in CRC tissues, whereas depletion of IL-8 led to a reduced angiogenic activity of LIFR in CRC cells. In addition, LIFR increased phosphorylation level of Erk, which regulates il-8 transcription. We conclude that LIFR is possibly a valuable prognostic marker for CRC. Our results also implicate a mechanism by which LIFR regulates tumor angiogenesis through Erk/IL-8 pathway, and that LIFR could be a potential therapeutic target for CRC.


Assuntos
Neoplasias Colorretais/irrigação sanguínea , Células Endoteliais/patologia , Interleucina-8/metabolismo , Subunidade alfa de Receptor de Fator Inibidor de Leucemia/metabolismo , Neovascularização Patológica/patologia , Idoso , Animais , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Regulação para Baixo , Feminino , Seguimentos , Células Endoteliais da Veia Umbilical Humana , Humanos , Interleucina-8/genética , Subunidade alfa de Receptor de Fator Inibidor de Leucemia/genética , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Neovascularização Patológica/mortalidade , Prognóstico , RNA Interferente Pequeno/metabolismo , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Angew Chem Int Ed Engl ; 57(31): 9965-9969, 2018 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-29786934

RESUMO

The weak photoluminescence of silver nanoclusters prevents their broad application as luminescent nanomaterials. Recent experiments, however, have shown that gold doping can significantly enhance the photoluminescence intensity of Ag29 nanoclusters but the molecular and physical origins of this effect remain unknown. Therefore, we have computationally explored the geometric and electronic structures of Ag29 and gold-doped Ag29-x Aux (x=1-5) nanoclusters in the S0 and S1 states. We found that 1) relativistic effects that are mainly due to the Au atoms play an important role in enhancing the fluorescence intensity, especially for highly doped Ag26 Au3 , Ag25 Au4 , and Ag24 Au5 , and that 2) heteronuclear Au-Ag bonds can increase the stability and regulate the fluorescence intensity of isomers of these gold-doped nanoclusters. These novel findings could help design doped silver nanoclusters with excellent luminescence properties.

7.
J Comput Chem ; 38(28): 2388-2395, 2017 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-28762255

RESUMO

N-alkenyl maleimides are found to exhibit spin state-specific chemoselectivities for [2 + 2] and [5 + 2] photocycloadditions; but, reaction mechanism is still unclear. In this work, we have used high-level electronic structure methods (DFT, CASSCF, and CASPT2) to explore [2 + 2] and [5 + 2] photocycloaddition reaction paths of an N-alkenyl maleimide in the S1 and T1 states as well as relevant photophysical processes. It is found that in the S1 state [5 + 2] photocycloaddition reaction is barrierless and thus overwhelmingly dominant; [2 + 2] photocycloaddition reaction is unimportant because of its large barrier. On the contrary, in the T1 state [2 + 2] photocycloaddition reaction is much more favorable than [5 + 2] photocyclo-addition reaction. Mechanistically, both S1 [5 + 2] and T1 [2 + 2] photocycloaddition reactions occur in a stepwise, nonadiabatic means. In the S1 [5 + 2] reaction, the secondary C atom of the ethenyl moiety first attacks the N atom of the maleimide moiety forming an S1 intermediate, which then decays to the S0 state as a result of an S1 → S0 internal conversion. In the T1 [2 + 2] reaction, the terminal C atom of the ethenyl moiety first attacks the C atom of the maleimide moiety, followed by a T1 → S0 intersystem crossing process to the S0 state. In the S0 state, the second CC bond is formed. Our present computational results not only rationalize available experiments but also provide new mechanistic insights. © 2017 Wiley Periodicals, Inc.

8.
J Comput Chem ; 38(27): 2289-2297, 2017 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-28718966

RESUMO

Silver-mediated hydroazidation of unactivated alkynes has been developed as a new method for the synthesis of vinyl azides. Density functional theory calculations toward this reaction reveal that terminal alkynes with TMS-N3 participated hydroazidation proceed through HN3 formation, deprotonation and silver acetylides formation, nucleophilic addition, and protonation of terminal carbon by AgHCO3 . It is also found that water molecules and activation modes of Ag (I) have a significant influence on the title reaction mechanism. Initially, catalyst Ag2 CO3 coordinates preferentially with internal N atom of TMS-N3 to assist water as hydrogen source and proton-shuttle in facilitating HN3 formation. Then, the regioselective anti-addition of HN3 to triple bond of active silver-acetylide or ethynyl carbinols affords product vinyl azide via Ag-C σ-bond activation or Ag…C π-coordination activation modes, and the former one is more favorable. The origin of the difference regioselectivity is ascribed to the electronic and orbital effects of the reactive sites. Moreover, Ag2 CO3 is the critical catalyst, acting as activator, base, and stabilizer to promote the HN3 and vinyl azide formation. Water molecule plays an important role as proton shuttle to promote HN3 and key active silver acetylides formation, thus improving the yield of product. © 2017 Wiley Periodicals, Inc.

9.
Phys Chem Chem Phys ; 19(21): 13524-13533, 2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28498381

RESUMO

In contrast to photophysics of thio-substituted nucleobases, their photoinduced cross-linking reactions with canonical nucleobases remain scarcely investigated computationally. In this work, we have adopted combined CASPT2/PCM//CASSCF and B3LYP-D3/PCM electronic structure methods to study this kind of photochemical reaction of 5-fluoro-4-thiouridine (truncated 5-fluoro-1-methyl-4-thiouracil used in calculations) and 1-methylthymine (referred to as thymine for clarity hereinafter). On the basis of CASPT2/PCM computed results, we have proposed two efficient excited-state relaxation pathways to populate the lowest T1 state of the complex of 5-fluoro-1-methyl-4-thiouracil and thymine from its initially populated S2(1ππ*) state. In the first one, the S2 system first hops to the S1 state via an S2/S1 conical intersection, followed by a direct S1 → T1 intersystem crossing process enhanced by large S1/T1 spin-orbit coupling. In the second path, the resultant S1 system first jumps to the T2 state, from which an efficient T2 → T1 internal conversion occurs. The T1 cross-linking reaction is overall divided into two phases. The first phase is a stepwise and nonadiabatic photocyclization reaction, which starts from the T1 complex and ends up with an S0 thietane intermediate. The second phase is a thermal reaction. The system first rearranges its four- and six-membered rings to form three new rings; then, an S0 fluorine atom transfer occurs, followed by the formation of photoproducts. Finally, the present work paves the way for studying light-induced cross-linking reactions of thionucleobases with canonical bases in DNA and RNA.


Assuntos
Tiouridina/análogos & derivados , Timina/química , Ciclização , Modelos Químicos , Estrutura Molecular , Processos Fotoquímicos , Tiouridina/química
10.
J Phys Chem A ; 121(22): 4253-4262, 2017 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-28513156

RESUMO

Photoinduced chemical reactions of organic compounds at the marine boundary layer have recently attracted significant experimental attention because this kind of photoreactions has been proposed to have substantial impact on local new particle formation and their photoproducts could be a source of secondary organic aerosols. In this work, we have employed first-principles density functional theory method combined with cluster models to systematically explore photochemical reaction pathways of nonanoic acids (NAs) to form volatile saturated and unsaturated C9 and C8 aldehydes at air-water interfaces. On the basis of the results, we have found that the formation of C9 aldehydes is not initiated by intermolecular Norrish type II reaction between two NAs but by intramolecular T1 C-O bond fission of NA generating acyl and hydroxyl radicals. Subsequently, saturated C9 aldehydes are formed through hydrogenation reaction of acyl radical by another intact NA. Following two dehydrogenation reactions, unsaturated C9 aldehydes are generated. In parallel, the pathway to C8 aldehydes is initiated by T1 C-C bond fission of NA, which generates octyl and carboxyl radicals; then, an octanol is formed through recombination reaction of octyl with hydroxyl radical. In the following, two dehydrogenation reactions result into an enol intermediate from which saturated C8 aldehydes are produced via NA-assisted intermolecular hydrogen transfer. Finally, two dehydrogenation reactions generate unsaturated C8 aldehydes. In these reactions, water and NA molecules are found to play important roles. They significantly reduce relevant reaction barriers. Our work has also explored oxygenation reactions of NA with molecular oxygen and radical-radical dimerization reactions.

11.
PLoS One ; 12(4): e0176802, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28453560

RESUMO

The aim of our study was to determine the impact of genetic polymorphisms in the caspase (CASP) genes on prognosis of hepatocellular carcinoma (HCC). We genotyped 7 potentially functional polymorphisms in CASP3, CASP7, CASP8, CASP9, CASP10 genes in 362 HCC patients of receiving surgical resection of HCC tumor. The associations of genotype and haplotype with overall survival (OS) and disease free survival (DFS) were analyzed by using the Cox proportional hazards model. We found that the CASP9 rs4645981 C allele was significantly associated with positive effect on DFS (P = 0.011 and 0.016 for CT+CC vs. TT in univariate and multivariate analysis, respectively), CT genotype was associated with a better OS of HCC than the TT genotype both in univariate and multivariate analysis (P = 0.048 and 0.041, respectively). Moreover, the CASP3 rs2705897 GT genotype showed marginally significant association with decreased OS and DFS, compared with the GG genotype. One haplotype TT/TG in CASP3 (constructed by rs12108497 T>C and rs2705897 T>G) was significantly associated with decreased OS and DFS, compared to the common haplotype TT/TT both in univariate analysis (P = 0.021 and 0.026, respectively) and multivariate analysis (P = 0.025 and 0.030, respectively). The haplotype GT/GT in CASP9 (constructed by rs4645978 A>G and rs4645981 C>T) was significantly associated with decreased DFS both in univariate and multivariate analysis (P = 0.012 and 0.010, respectively). In conclusion, the CASP9 rs4645981 polymorphism, CASP3 and CASP9 haplotypes may be useful prognosis markers for HCC patients with surgical resection of tumor.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/cirurgia , Caspases/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/cirurgia , Polimorfismo de Nucleotídeo Único , Grupo com Ancestrais do Continente Asiático/genética , Carcinoma Hepatocelular/patologia , China , Intervalo Livre de Doença , Feminino , Predisposição Genética para Doença , Técnicas de Genotipagem , Haplótipos , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , Carga Tumoral
12.
Org Biomol Chem ; 15(7): 1580-1583, 2017 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-28120998

RESUMO

The radical coupling of isocyanides and alcohols/phenols promoted by silver in the presence of water is reported for the first time, which led to the formation of diverse carbamates. In contrast to the well-known 1,1-addition to form imidoyl radicals, a novel reaction mechanism, involving sequential hydration of isocyanides and coupling with alkoxyl/phenoxyl radicals, is disclosed by combining experimental and theoretical studies.

13.
Tumour Biol ; 37(7): 9931-42, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26815502

RESUMO

Single nucleotide polymorphisms (SNPs) within microRNAs (miRNAs) are considered potential markers for risk and prognosis of various cancers. In the current study, we aimed to determine whether miR-608 rs4919510 affected hepatocellular carcinoma (HCC) prognosis. We genotyped rs4919510 using DNA from blood samples of 362 HCC patients receiving surgical resection of HCC tumor. Associations between rs4919510 and overall survival (OS) and demographic characteristics and clinical features were estimated using the Cox proportional hazards model. Results showed that HCC patients who carried the rs4919510 CC genotype had a significantly longer OS compared to those who carried the GG genotype (P = 0.013, hazard ratio [HR] = 0.600, 95 % confidence interval [CI] 0.402-0.897) and the CG + GG genotype (P = 0.033, HR = 0.681, 95 % CI 0.479-0.970) in univariate analysis. Similar results were obtained in multivariate analysis. Further stratification analysis indicated that rs4919510 was significantly associated with OS in patients who were satisfied with one of the following criteria: male gender, HbsAg-positive, α-fetoprotein (AFP)-positive, tumor size >5 cm, cirrhosis, solitary tumor, I + II pTNM stage, or no tumor capsule. Finally, a significantly higher frequency of rs4919510 CC genotype was observed in patients with cirrhosis (22.9 %, 55/240) than those without cirrhosis (14.0 %, 17/121) (P = 0.047). In conclusion, our results illustrated the potential role of miR-608 rs4919510 as a prognostic marker for HCC patients undergoing surgical resection of the tumor.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/patologia , Estudos de Coortes , Feminino , Seguimentos , Genótipo , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Taxa de Sobrevida , Adulto Jovem
14.
Tumour Biol ; 37(7): 8961-72, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26753964

RESUMO

Single-nucleotide polymorphisms (SNPs) of microRNAs (miRNAs) are considered potential markers of cancer risk and prognosis in various cancers. In the current study, the primary aim is to determine whether the miR-492G>C polymorphism (rs2289030) altered hepatocellular carcinoma (HCC) prognosis. The SNP rs2289030 of miR-492 was genotyped using DNA from blood samples of 362 HCC patients that had undergone surgical resection of a HCC tumor. The associations between overall survival and demographic characteristics, clinical features, and the SNP rs2289030 were estimated using the Cox proportional hazards model. Results showed that patients who carried the CG genotype (P = 0.015, hazard ratio [HR] = 0.704, 95 % confidence interval [CI] 0.530-0.934) and CG+GG genotype (P = 0.011, HR = 0.703, 95 % CI 0.536-0.924) had significantly decreased risk of death compared to those with the CC genotype. Similar results were found in the multivariate analysis adjusted by tumor size and venous invasion. Further stratification analysis indicated that the effect of rs2289030 had more prominence in patients ≤50 years old and that reported ever using alcohol, male gender, a family history of HCC, being HbsAg or alpha fetoprotein (AFP) positive, differentiation I + II, presence of venous invasion or cirrhosis, multiple tumors, and pTNM stage I + II. Results from this study illustrate the potential use of miR-492 rs2289030 as a prognostic marker for HCC patients that have undergone a surgical resection of the tumor.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/mortalidade , Predisposição Genética para Doença/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidade , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/patologia , Feminino , Genótipo , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Adulto Jovem
15.
Hepatology ; 63(4): 1102-11, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26704347

RESUMO

UNLABELLED: Interferon (IFN)-α is a first-line therapy for chronic hepatitis B (CHB) patients but only initiates a response in a minority of patients. A genetic variant, rs7574865 in STAT4, was recently reported to be associated with risk of developing CHB and hepatitis B virus-related hepatocellular carcinoma. We aimed to determine whether this variant is associated with the response to IFNα treatment for hepatitis B e antigen (HBeAg)-positive CHB patients. We studied 466 HBeAg-positive CHB patients who received either IFNα-2b (n = 224) or pegylated IFNα-2a (n = 242) therapy for 48 weeks and were followed for an additional 24 weeks. The rate of sustained virologic response (SVR), defined as HBeAg seroconversion along with hepatitis B virus DNA level <2000 copies/mL at week 72, was compared among patients with different genotypes of rs7574865. After 48 weeks of treatment and 24 weeks off treatment, the SVR rates in the IFNα-2b and pegylated IFNα-2a therapy groups were 30.4% and 28.9%, respectively. Compared to the rs7574865 GT/TT genotype, the GG genotype (a risk factor of CHB and hepatitis B virus-related hepatocellular carcinoma) was significantly associated with a reduced SVR rate in both patients who received IFNα-2b therapy (21.1% versus 37.2%, P = 0.01) and those who received pegylated IFNα-2a therapy (18.0% versus 41.2%, P = 9.74 × 10(-5) ). In joint analysis of the 466 patients, the GG genotype was associated with an approximately half SVR rate compared to the GT/TT genotype (19.3% versus 39.1%, P = 4.15 × 10(-6) ). A multivariate logistic regression model including rs7574865 and clinical variables showed that rs7574865 was the most significant factor for the prediction of SVR. CONCLUSION: STAT4 rs7574865 is a reliable predictor of response to IFNα therapy for HBeAg-positive CHB patients and may be used for optimizing the treatment of CHB.


Assuntos
Variação Genética , Antígenos E da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/genética , Interferon-alfa/uso terapêutico , Fator de Transcrição STAT4/genética , Adulto , Idoso , China , Estudos de Coortes , Intervalos de Confiança , Bases de Dados Factuais , Feminino , Seguimentos , Genótipo , Antígenos E da Hepatite B/imunologia , Hepatite B Crônica/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Polimorfismo de Nucleotídeo Único , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Resultado do Tratamento
16.
ACS Appl Mater Interfaces ; 7(50): 27959-67, 2015 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-26619747

RESUMO

In this work, the chemical interaction of cathode and lithium polysulfides (LiPSs), which is a more targeted approach for completely preventing the shuttle of LiPSs in lithium-sulfur (Li-S) batteries, has been established on the electrode level. Through simply posttreating the ordinary sulfur cathode in atmospheric environment just for several minutes, the Au nanoparticles (Au NPs) were well-decorated on/in the surface and pores of the electrode composed of commercial acetylene black (CB) and sulfur powder. The Au NPs can covalently stabilize the sulfur/LiPSs, which is advantageous for restricting the shuttle effect. Moreover, the LiPSs reservoirs of Au NPs with high conductivity can significantly control the deposition of the trapped LiPSs, contributing to the uniform distribution of sulfur species upon charging/discharging. The slight modification of the cathode with <3 wt % Au NPs has favorably prospered the cycle capacity and stability of Li-S batteries. Moreover, this cathode exhibited an excellent anti-self-discharge ability. The slight decoration for the ordinary electrode, which can be easily accessed in the industrial process, provides a facile strategy for improving the performance of commercial carbon-based Li-S batteries toward practical application.

17.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 23(6): 1560-3, 2015 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-26708871

RESUMO

OBJECTIVE: To investigate the inductive therapeutic effects of imatinib combined with VP low dose regiment on adult patients with Ph-positive acute lymphoblastic leukemia (Ph(+) ALL). METHODS: Fourteen newly diagnosed adult patients with Ph(+) ALL were treated with VP regimen, and imatinib (400 mg/d) was added at the 8(th) day. VP regimen would be stopped when neutropenia lasted for 1 week or complicated with infection, fever, etc. Therapeutic effects were assessed by bone marrow morphology and quantitative analysis of BCR/ABL:ABL at the 28(th) - 33(rd) day. Patients could be treated with imatinib combined with chemotherapy for consolidation and maintenance therapy or were treated with allogeneic hematopoietic stem cell transplantation after complete remission. RESULTS: Fourteen cases obtained CR1 after first course of treatment, the median decline of BCR/ABA:ABL was 55.89 (10.25 -180.97) %; during the induction chemotherapy, pulmonary infection occurred in 3 patients, diarrhea in 1 patients, facial edema in 3 patients, however, all these patients were cured after symptomatic treatment, only 1 patient died of relapse after transplantation. CONCLUSION: In the period of tyrosine kinase inhibitor (TKI), inductive chemotherapy combined with imatinib and low dose VP can obtaine satisfactory CR rate and decrease the toxicity of the traditional drugs. It is suggested that TKI combined with VP regimen chemotherapy can achieve CR1 and make possible for allo-HSCT, from which patients can achieve the long-term survival.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica , Medula Óssea , Cisplatino , Proteínas de Fusão bcr-abl , Transplante de Células-Tronco Hematopoéticas , Humanos , Mesilato de Imatinib , Quimioterapia de Indução , Neutropenia , Inibidores de Proteínas Quinases , Recidiva , Indução de Remissão , Transplante Homólogo , Vindesina
18.
Am J Cancer Res ; 5(10): 3249-59, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26693075

RESUMO

The apoptotic pathway is important in the control of vital processes of hepatocellular carcinoma (HCC). In the current study, we aimed to determine whether apoptotic gene-related polymorphisms modified HCC prognosis. We genotyped 16 single nucleotide polymorphisms (SNPs) in 10 core genes (TP53, TP53INP1, TP53BP1, CDKN2A, CDKN1A, CDKN1B, MDM2, BAX, CCDN1 and BCL2) in the apoptotic pathway by using DNA from blood samples of 362 HCC patients receiving surgical resection of HCC tumor. The associations between genotypes/haplotypes of the 10 genes and overall survival (OS) of HCC patients were assessed using the Cox proportional hazards model. We found one CDKN1B haplotype CCT/ACT (constructed by rs36228499 C>A, rs34330 C>T and rs2066827 T>G) significantly associated with decreased OS of HCC patients, compared to the common haplotype ACT/CTT both in univariate analysis (P=0.013, HR=1.198, 95% CI: 1.039-1.381) and multivariate analysis (P=0.006, HR=1.224, 95% CI: 1.059-1.413). We also find two SNPs (rs560191 G>C and rs2602141 T>G) in TP53BP1 shown to be marginally significantly associated with decreased OS of HCC patients. However, none of the other SNPs or haplotypes were significantly associated with HCC OS. Our results illustrated the potential use of CDKN1B haplotype as a prognostic marker for HCC patients with surgical resection of tumor.

19.
Sci Rep ; 5: 16278, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26538132

RESUMO

Recent genome-wide associated studies (GWASs) have revealed several common loci associated with the risk of hepatitis B virus (HBV)- or hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC). We selected 15 single nucleotide polymorphisms (SNPs) identified through GWASs on HBV- or HCV-related HCC, and genotyped them in two independent Chinese cohorts of chronic HBV carriers, including 712 LC cases and 2601 controls. The association of each SNP with the risk of HBV-related LC was assessed by meta-analysis of the two cohorts. Of the 12 SNPs reported in HBV-related HCC GWASs, five SNPs (rs7574865 in STAT4, rs9267673 near C2, rs2647073 and rs3997872 near HLA-DRB1 and rs9275319 near HLA-DQ), were found to be significantly associated with the risk of HBV-related LC (rs7574865: P = 1.79 × 10(-2), OR = 1.17, 95% CI = 1.03-1.34; rs9267673: P = 4.91 × 10(-4), OR = 1.37, 95% CI = 1.15-1.63; rs2647073: P = 3.53 × 10(-5), OR = 1.63, 95% CI = 1.29-2.06; rs3997872: P = 4.22 × 10(-4), OR = 1.86, 95% CI = 1.32-2.62; rs9275319: P = 1.30 × 10(-2), OR = 1.32, 95% CI = 1.06-1.64). However, among the three SNPs associated with the risk of HCV-related HCC in previous GWASs, none of them showed significant association with the risk of HBV-related LC. Our results suggested that genetic variants associated with HBV-related hepatocarcinogenesis may already play an important role in the progression from CHB to LC.


Assuntos
Antígenos HLA-DQ/genética , Cadeias HLA-DRB1/genética , Vírus da Hepatite B/metabolismo , Cirrose Hepática/genética , Cirrose Hepática/virologia , Polimorfismo de Nucleotídeo Único/genética , Fator de Transcrição STAT4/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Estudos de Casos e Controles , China , Feminino , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Genótipo , Hepatite B Crônica/genética , Hepatite B Crônica/virologia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Risco
20.
ACS Appl Mater Interfaces ; 7(30): 16440-9, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-26158231

RESUMO

The ability of nanostructures to facilitate the generation of reactive oxygen species and charge carriers underlies many of their chemical and biological activities. Elucidating which factors are essential and how these influence the production of various active intermediates is fundamental to understanding potential applications of these nanostructures, as well as potential risks. Using electron spin resonance spectroscopy coupled with spin trapping and spin labeling techniques, we assessed 3 mixed metal sulfides of varying compositions for their abilities to generate reactive oxygen species, photogenerate electrons, and consume oxygen during photoirradiation. We found these irradiated mixed metal sulfides exhibited composition dependent generation of ROS: ZnIn2S4 can generate (•)OH, O2(-•) and (1)O2; CdIn2S4 can produce O2(-•) and (1)O2, while AgInS2 only produces O2(-•). Our characterizations of the reactivity of the photogenerated electrons and consumption of dissolved oxygen, performed using spin labeling, showed the same trend in activity: ZnIn2S4 > CdIn2S4 > AgInS2. These intrinsic abilities to generate ROS and the reactivity of charge carriers correlated closely with the photocatalytic degradation and photoassisted antibacterial activities of these nanomaterials.


Assuntos
Nanopartículas Metálicas/química , Nanopartículas Metálicas/efeitos da radiação , Fotoquímica/métodos , Espécies Reativas de Oxigênio/síntese química , Sulfetos/química , Sulfetos/efeitos da radiação , Catálise/efeitos da radiação , Luz , Teste de Materiais , Espécies Reativas de Oxigênio/efeitos da radiação , Estatística como Assunto
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