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1.
Angew Chem Int Ed Engl ; 58(50): 18146-18149, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31591785

RESUMO

The key issue holding back the application of solid polymeric electrolytes in high-energy density lithium metal batteries is the contradictory requirements of high ion conductivity and mechanical stability. In this work, self-healable solid polymeric electrolytes (SHSPEs) with rigid-flexible backbones and high ion conductivity are synthesized by a facile condensation polymerization approach. The all-solid Li metal full batteries based on the SHSPEs possess freely bending flexibility and stable cycling performance as a result of the more disciplined metal Li plating/stripping, which have great implications as long-lifespan energy sources compatible with other wearable devices.

2.
J Virol ; 93(1)2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30333168

RESUMO

Type I interferon (IFN) inhibits viruses by inducing the expression of antiviral proteins. The IFN-induced myxovirus resistance B (MxB) protein has been reported to inhibit a limited number of viruses, including HIV-1 and herpesviruses, but its antiviral coverage remains to be explored further. Here we show that MxB interferes with RNA replication of hepatitis C virus (HCV) and significantly inhibits viral replication in a cyclophilin A (CypA)-dependent manner. Our data further show that MxB interacts with the HCV protein NS5A, thereby impairing NS5A interaction with CypA and NS5A localization to the endoplasmic reticulum, two events essential for HCV RNA replication. Interestingly, we found that MxB significantly inhibits two additional CypA-dependent viruses of the Flaviviridae family, namely, Japanese encephalitis virus and dengue virus, suggesting a potential link between virus dependence on CypA and virus susceptibility to MxB inhibition. Collectively, these data have identified MxB as a key factor behind IFN-mediated suppression of HCV infection, and they suggest that other CypA-dependent viruses may also be subjected to MxB restriction.IMPORTANCE Viruses of the Flaviviridae family cause major illness and death around the world and thus pose a great threat to human health. Here we show that IFN-inducible MxB restricts several members of the Flaviviridae, including HCV, Japanese encephalitis virus, and dengue virus. This finding not only suggests an active role of MxB in combating these major pathogenic human viruses but also significantly expands the antiviral spectrum of MxB. Our study further strengthens the link between virus dependence on CypA and susceptibility to MxB restriction and also suggests that MxB may employ a common mechanism to inhibit different viruses. Elucidating the antiviral functions of MxB advances our understanding of IFN-mediated host antiviral defense and may open new avenues to the development of novel antiviral therapeutics.


Assuntos
Ciclofilina A/farmacologia , Hepacivirus/fisiologia , Interferons/farmacologia , Proteínas de Resistência a Myxovirus/metabolismo , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacos , Animais , Linhagem Celular , Chlorocebus aethiops , Ciclosporina/farmacologia , Retículo Endoplasmático/metabolismo , Técnicas de Silenciamento de Genes , Células HEK293 , Hepacivirus/efeitos dos fármacos , Humanos , Proteínas de Resistência a Myxovirus/genética , Ligação Proteica/efeitos dos fármacos , Células Vero
3.
Nanoscale ; 10(15): 6832-6836, 2018 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-29610786

RESUMO

F-Doped MnWO4 nano-particles were synthesized by a one-pot hydrothermal reaction. When evaluated as an electrode material for a Li ion battery, the F-doped nano-MnWO4 delivers a theoretical capacity of 708 mA h g-1 and a long cycle life, as demonstrated by more than 85% capacity retention when cycled for 150 cycles.

4.
Chem Commun (Camb) ; 54(14): 1714-1717, 2018 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-29243767

RESUMO

A novel Bi-based anode material with a stable alloy reaction is prepared by a solvothermal method. The Mg storage mechanism is elucidated for the first time. Owing to the space confinement of in situ conversion, the anode material shows superior magnesium storage performance, especially the cycling stability (capacity retention >96% after 100 cycles).

5.
PLoS Pathog ; 13(9): e1006625, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28938017

RESUMO

Enterovirus 71 (EV71) is the major causative agent of hand, foot and mouth disease (HFMD) in children, causing severe clinical outcomes and even death. Here, we report an important role of the highly conserved alanine residue at position 107 in the capsid protein VP1 (VP1A107) in the efficient replication of EV71. Substitutional mutations of VP1A107 significantly diminish viral growth kinetics without significant effect on viral entry, expression of viral genes and viral production. The results of mechanistic studies reveal that VP1A107 regulates the efficient cleavage of the VP0 precursor during EV71 assembly, which is required, in the next round of infection, for the transformation of the mature virion (160S) into an intermediate or A-particle (135S), a key step of virus uncoating. Furthermore, the results of molecular dynamic simulations and hydrogen-bond networks analysis of VP1A107 suggest that flexibility of the VP1 BC loop or the region surrounding the VP1107 residue directly correlates with viral infectivity. It is possible that sufficient flexibility of the region surrounding the VP1107 residue favors VP0 conformational change that is required for the efficient cleavage of VP0 as well as subsequent viral uncoating and viral replication. Taken together, our data reveal the structural role of the highly conserved VP1A107 in regulating EV71 maturation. Characterization of this novel determinant of EV71 virulence would promote the study on pathogenesis of Enteroviruses.


Assuntos
Enterovirus Humano A/fisiologia , Infecções por Enterovirus/virologia , Células Vero/virologia , Replicação Viral/genética , Aminoácidos/genética , Animais , Proteínas do Capsídeo/metabolismo , Chlorocebus aethiops , Mutação de Sentido Incorreto/genética , Internalização do Vírus
6.
Sci Rep ; 7(1): 5093, 2017 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-28698545

RESUMO

Protein kinase B (PknB) is one of the Mycobacterium tuberculosis serine/threonine protein kinases and has an essential role in sustaining mycobacterial growth. Here, we identified and characterized a novel small molecule compound named IMB-YH-8 that inhibited PknB and served as anti-mycobacteria lead compound. IMB-YH-8 inhibited PknB auto-phosphorylation and the phosphorylation of GarA by PknB in a dose-dependent manner. The compound did not inhibit human Akt1 or other serine/threonine kinases in M. tuberculosis except for the highly homologous PknA. IMB-YH-8 bound to PknB with a moderate affinity. Molecular docking revealed that IMB-YH-8 interacts with the catalytic domain of PknB. Observations of electron microscopy showed that IMB-YH-8 changed the morphology of H37Rv and disrupted the cell wall. The differential transcriptional response of M. tuberculosis to IMB-YH-8 revealed changes in SigH regulatory pathways modulated by PknB. Notably IMB-YH-8 not only potently inhibited drug-sensitive and multidrug-resistant clinical isolates but also exhibited a dose dependent inhibition of intracellular M. tuberculosis. Taken together, these in vitro data demonstrate that IMB-YH-8 is a novel inhibitor of PknB, which potently prevents growth of M. tuberculosis. It is as yet unclear whether inhibition of PknA contributes to the anti-tubercular action of IMB-YH-8.


Assuntos
Anisóis/uso terapêutico , Antituberculosos/uso terapêutico , Butiratos/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Tuberculose/tratamento farmacológico , Anisóis/química , Anisóis/farmacologia , Antituberculosos/química , Antituberculosos/farmacologia , Proteínas de Bactérias/metabolismo , Butiratos/química , Butiratos/farmacologia , Domínio Catalítico , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Farmacorresistência Bacteriana/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/enzimologia , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/ultraestrutura , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Estereoisomerismo , Especificidade por Substrato/efeitos dos fármacos , Tuberculose/microbiologia
7.
Sci Rep ; 6: 31472, 2016 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-27510727

RESUMO

Multidrug resistance is a major limitation for microtubule-binding agents in cancer treatment. Here we report a novel microtubule inhibitor (2-morpholin-4-yl-5-nitro-benzoic acid 4-methylsulfanyl-benzyl ester, IMB5046), its cytotoxicity against multidrug-resistant cell lines and its antitumor efficacy in animal models. IMB5046 disrupted microtubule structures in cells and inhibited purified tubulin polymerization in vitro. It bound to the colchicine pocket of tubulin. IMB5046 displayed potent cytotoxicity against multiple tumor cell lines with an IC50 range of 0.037-0.426 µM. Notably, several multidrug-resistant cell lines which were resistant to colchicine, vincristine and paclitaxel remained sensitive to IMB5046. IMB5046 was not a P-glycoprotein substrate. IMB5046 blocked cell cycle at G2/M phase and induced cell apoptosis. Microarray assay indicated that the differentially expressed genes after IMB5046 treatment were highly related to immune system, cell death and cancer. In a mouse xenograft model IMB5046 inhibited the growth of human lung tumor xenograft by 83% at a well-tolerated dose. It is concluded that IMB5046 is a tubulin polymerization inhibitor with novel chemical structure and can overcome multidrug resistance. It is a promising lead compound for cancer chemotherapy, especially for treatment of multidrug-resistant tumors.


Assuntos
Benzoatos/administração & dosagem , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Morfolinas/administração & dosagem , Neoplasias/tratamento farmacológico , Nitrobenzoatos/administração & dosagem , Moduladores de Tubulina/administração & dosagem , Células A549 , Animais , Benzoatos/química , Benzoatos/farmacologia , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Células HT29 , Humanos , Camundongos , Morfolinas/química , Morfolinas/farmacologia , Células NIH 3T3 , Neoplasias/genética , Nitrobenzoatos/química , Nitrobenzoatos/farmacologia , Moduladores de Tubulina/química , Moduladores de Tubulina/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Yao Xue Xue Bao ; 51(2): 287-93, 2016 02.
Artigo em Chinês | MEDLINE | ID: mdl-29856583

RESUMO

Androgen receptor(AR) plays an important role in the maintenance of prostate function and development of prostate cancer. AR is the key target in the therapy of prostate cancer. In this study, a cell-based screening assay was established by dual-luciferase reporter system to analyze the activity of AR. In the screening assay, we detected the anti-prostate cancer activities of rhodiola root extract, wild kiwifruit root extract and tripterygium wilfordii root extract, which may provide a new strategy for the treatment of prostate cancer.


Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Antineoplásicos/farmacologia , Avaliação Pré-Clínica de Medicamentos , Extratos Vegetais/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Linhagem Celular Tumoral , Humanos , Luciferases , Masculino , Receptores Androgênicos
9.
Yao Xue Xue Bao ; 50(7): 797-801, 2015 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-26552138

RESUMO

Drug therapy is one of the efficient methods for prostate cancer treatment. However, drug resistance greatly hindered the treatment of prostate cancer patients. Herein, the mechanisms of drug resistance in prostate cancer have been exhaustively reviewed, and that can provide an alternative strategy and new targets for anti-prostate cancer therapy.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias da Próstata/tratamento farmacológico , Humanos , Masculino
10.
Yi Chuan ; 37(5): 480-6, 2015 05.
Artigo em Inglês | MEDLINE | ID: mdl-25998437

RESUMO

In the event of acute infection, only a few HIV-1 viral variants can establish the initial productive clinical infection, and these viral variants are known as transmitted/founder viruses (T/F viruses). As one of the accessory proteins of HIV-1, viral protein R (Vpr) plays an important role in viral replication. Therefore, the characterization of T/F virus Vpr is beneficial to understand how virus replicates in a new host. In this study, flow cytometry was used to analyze the effect of G2arrest and cell apoptosis induced by the T/F virus Vpr and the chronic strain MJ4 Vpr. The results showed that the ability of T/F virus ZM246 Vpr and ZM247 Vpr inducing G2arrest and cell apoptosis are more potent than the MJ4 Vpr. The comparison of protein sequences indicated that the amino acids of 77, 85 and 94 contain high freqency mutations, suggesting that these sites may be involved in inducing G2arrest and cell apoptosis. Taken together, our work suggests that in acute infections, T/F viruses increase the capacity of G2arrest and cell apoptosis and promote viral replication and transmission in a new host by Vpr genetic mutation.


Assuntos
Apoptose , Ciclo Celular , Infecções por HIV/fisiopatologia , HIV-1/genética , Produtos do Gene vpr do Vírus da Imunodeficiência Humana/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Infecções por HIV/virologia , HIV-1/química , HIV-1/fisiologia , Humanos , Dados de Sequência Molecular , Alinhamento de Sequência , Produtos do Gene vpr do Vírus da Imunodeficiência Humana/química , Produtos do Gene vpr do Vírus da Imunodeficiência Humana/genética
11.
Virus Genes ; 47(2): 235-43, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23877719

RESUMO

Enterovirus 71 (EV71) is the major causative agent of hand, foot, and mouth disease and induces fatal neurological complications. In recent years, this virus has become a major threat to public health in the Asia-Pacific region, while no effective antiviral therapies and vaccines are currently available. In this study, we constructed and characterized for the first time an infectious full-length EV71 cDNA clone derived from the SHZH98 strain, which was the first subgenotype C4 strain isolated in China. Our data demonstrate that the rescued EV71 viruses exhibited growth kinetics in vitro and morphologies similar to those of the BrCr-TR strain and reached a maximum titer of 10(7.5) TCID50/ml. Although the rescued viruses were able to infect suckling mice, no typical symptoms of EV71 infection were observed for up to 18 days post-inoculation. Taken together our research provides an important tool to study the epidemic strains of EV71 in the Asia-Pacific region and promote the development of vaccines.


Assuntos
DNA Complementar/genética , Enterovirus Humano A/genética , Enterovirus Humano A/fisiologia , RNA Viral/genética , Animais , China , DNA Complementar/química , Modelos Animais de Doenças , Enterovirus Humano A/isolamento & purificação , Genótipo , Doença de Mão, Pé e Boca/patologia , Doença de Mão, Pé e Boca/virologia , Camundongos , Dados de Sequência Molecular , Análise de Sequência de DNA , Carga Viral , Cultura de Vírus , Replicação Viral
12.
Yao Xue Xue Bao ; 47(9): 1159-63, 2012 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-23227545

RESUMO

Influenza virus RNA-dependent RNA polymerase (RdRP) is essential for replication and expression of influenza virus genome. Viral genomic sequences encoding RdRP are highly conservative, thus making it a potential anti-influenza drug target. A cell-based influenza RdRP inhibitor screening assay was established by a luciferase reporter system to analyze the activity of RdRP. Specificity study and statistic analysis showed that the screening assay is sensitive and reproducible.


Assuntos
Antivirais , Avaliação Pré-Clínica de Medicamentos/métodos , Genes Reporter , Luciferases/metabolismo , RNA Polimerase Dependente de RNA/antagonistas & inibidores , RNA Polimerase Dependente de RNA/metabolismo , Amantadina/farmacologia , Antivirais/isolamento & purificação , Antivirais/farmacologia , Células HEK293 , Humanos , Alphainfluenzavirus/enzimologia , Luciferases/genética , Oseltamivir/farmacologia , Plasmídeos , Reprodutibilidade dos Testes , Ribavirina/farmacologia , Sensibilidade e Especificidade , Transfecção , Zanamivir/farmacologia
13.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 25(5): 406-9, 2009 May.
Artigo em Chinês | MEDLINE | ID: mdl-19426596

RESUMO

AIM: To explore the regulatory effects of Egr-1 promoter sequences in transcriptional targeting by 5-fluorouracil(5-Fu) on the expression of hematopoietic growth factor genes. METHODS: The human Flt3 Ligand(FL) cDNA and the enhanced green fluorescent protein (EGFP) cDNA were linked with IRES and then inserted into the expression vector pCIneo under control of the Egr-1 promoter(Egr-EF). The vector was transferred into human bone marrow stromal cell line HFCL. The transfected cells (HFCL/EF) were exposed to the clinically important anticancer agent 5-fluorouracil. The activity of EGFP in HFCL/EF cells was detected by FACS. The expression of FL in HFCL/EF postchemotherapy was confirmed by ELISA, Western blot and RT-PCR, repectively. The effect of FL in HFCL/EF cultural supernatants on the expansion of CD34(+); cells and CFU-GM was studied. The effect of N-acetylcysteine (a free radical scavenger) on FL production following the exposure to 5-Fu was examined. RESULTS: The activity of EGFP and the amount of secreted FL in HFCL/EF cells exposed to 5-Fu increased compared to those in non-5-Fu group. The effects of FL in HFCL/EF cultural supernatants on the expansion of CD34(+); cells and CFU-GM were more significant than those of non-5-Fu group. N-acetylcysteine significantly decreased the concentration of FL produced by HFCL/EF treated with 5-FU. CONCLUSION: The therapy of hematopoietic growth factor gene regulated by Egr-1 promoter can protect hematopoiesis from 5-Fu injury.


Assuntos
Proteína 1 de Resposta de Crescimento Precoce/genética , Fluoruracila/farmacologia , Proteínas de Membrana/genética , Regiões Promotoras Genéticas/genética , Acetilcisteína/farmacologia , Antígenos CD34/sangue , Antimetabólitos Antineoplásicos/farmacologia , Western Blotting , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/farmacologia , Sangue Fetal/citologia , Citometria de Fluxo , Sequestradores de Radicais Livres/farmacologia , Expressão Gênica/efeitos dos fármacos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Proteínas de Membrana/metabolismo , Microscopia de Fluorescência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
14.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 17(2): 417-21, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19379579

RESUMO

This study was purposed to investigate the effect of hematopoietic growth factor expression regulated by Egr-1 promoter on the recovery of hematopoietic function in bearing-melanoma mice after chemotherapy with doxorubicin (ADM). The human GM-CSF cDNA and enhanced green fluorescence protein (GFP) cDNA were linked together with internal ribozyme entry site (IRES) and then were inserted into the expression vector pCI-neo under control of the Egr-1 promoter (Egr-EG). This vector was transduced into human bone marrow stromal cell lines HFCL by lipofectamine and was transfused in severe combined immunodeficiency (SCID) mice. The experimental mice were randomly divided into 4 groups (6 mice in each group): (1) HFCL/EG + ADM group in which the HFCL/EG cells were transplanted intravenously in SCID mice bearing melanoma, ADM was given intraperitoneally after 3 days; (2) HFCL + ADM group in which the HFCL cells were transplanted intravenously, ADM was given intraperitoneally after 3 days; (3) HPCL/EG group in which HFCL/EG cells were transplanted alone; (4) HFCL group in which HFCL cells were transplanted alone. The dynamic change of peripheral blood picture was assayed by hemocytometer; the eGFP(+) human stromal cells were detected by flow cytometry; the expression of GM-CSF mRNA and protein were determined by RT-PCR and Western blot respectively. The results indicated that as compared with HFCL/EG and HFCL groups, the leukocyte count in HFCL/EG + ADM group decreased, but decrease level was weaker than that in HFCL + ADM group, meanwhile the recovery of leukocyte count was earlier than that in HFCL + ADM group. The CFU-GM amount between 4 groups showed no significant difference. The detection results showed that the inhibitory rate of tumor was related to chemotherapy, but not to expression of exogenous gene; the eGFP(+) stromal cells existed in bone marrow of mice treated with ADM. The RT-PCR and Western blot assays revealed enhancement of GM-CSF mRNA and protein. It is concluded that the ADM-inducible GM-CSF gene therapy regulated by Egr-1 promoter may promote the hematopoietic recovery after chemotherapy.


Assuntos
Doxorrubicina/farmacologia , Proteína 1 de Resposta de Crescimento Precoce/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Hematopoese/efeitos dos fármacos , Animais , Feminino , Expressão Gênica , Vetores Genéticos , Células-Tronco Hematopoéticas , Humanos , Camundongos , Camundongos SCID , Regiões Promotoras Genéticas
15.
Chemotherapy ; 54(5): 357-63, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18772588

RESUMO

BACKGROUND: Extensive trials have indicated that cancer cells with high glycolytic activity exhibit decreased sensitivity to anticancer agents. Moreover, recent research has proven that specific inhibitors of hexokinase (HK) II, a key glycolytic enzyme, may enhance the activity of anticancer drugs. The aim of this study was to investigate the effect and mechanisms of HK II on chemosensitivity of a colon cancer cell line (LoVo) to 5-fluorouracil (5-FU). METHODS: HK II gene expression was downregulated by RNA interference in the colon cancer cell line LoVo, which was detected by Western blot analysis. Then the IC(50) value of 5-FU was determined in LoVo cells via MTT assay. In addition, cell apoptosis and mitochondrial membrane potential (MMP) were assessed by flow cytometry and caspase-3 activity by its substrate color reaction. RESULTS: In LoVo cells, HK II downregulation resulted in a decreased IC(50) value of 5-FU and increased apoptosis. Furthermore, HK II downregulation resulted in a decreased MPP and activation of caspase-3. CONCLUSION: Our findings suggest that targeting HK II may be beneficial for patients with colon cancer treated with 5-FU.


Assuntos
Neoplasias do Colo/enzimologia , Neoplasias do Colo/patologia , Regulação para Baixo , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica , Hexoquinase/genética , Hexoquinase/metabolismo , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Ativação Enzimática/efeitos dos fármacos , Humanos , Metaloproteinases da Matriz/metabolismo , Interferência de RNA
16.
Zhonghua Yi Xue Za Zhi ; 87(15): 1058-62, 2007 Apr 17.
Artigo em Chinês | MEDLINE | ID: mdl-17672972

RESUMO

OBJECTIVE: To investigate the expression of hexokinase (HK)-II gene in human colon cancer cells and the therapeutic significance of inhibition of HK-II gene. METHODS: Human colon cancer cells of the lines HCT-116, LOVO, HT-19, and SW480 were cultured. The mRNA expression and protein expression of HK-II in these cells were detected by RT-PCR and Western blotting respectively. 3-Bromopyruvic acid (3-BrPA), a HK-II specific inhibitor, of different concentrations was added into the culture fluid of the colon cancer cells for 48 h, then MTT method was used to examine the proliferation of the cells. 3-BrPA combined with adriamycin (ADM) of the concentrations of 0.05 and 0.1 microg/ml, or with oxaliplatin (L-OHP) of the concentration of 0.5 and 1.0 microg/ml was added into culture fluid for 48 h to observe the change of the cell proliferation rate. 3-BrPA of different concentrations was co-cultivated with LOVO cells for 24 h, and then enzyme labeling instrument was used to measure the activity of caspase-3, a cell apoptosis signal. 3-BrPA and CaCl2 were added into the culture fluid of LOVO cells and then ultra-violet spectrum was used to detect the mitochondrial permeability transition pore (PTP) opening degree. Flow cytometry (FCM), with addition of 10 microg/ml Rh123, was used to measure the mitochondrial membrane potential (DeltaPsim) of LOVO cells. RESULTS: Both HK-II mRNA and HK-II protein were expressed in the HCT-116, LOVO, HT-19, and SW480 cells. Treated by 3-BrPA combined with ADM of the concentrations of 0.05 and 0.1 microg/ml for 48 h, the cell proliferation inhibiting rates in the 4 lines were increased from 5.1% +/- 1.3% and 10.5% +/- 2.0% to 46.5% +/- 3.2% and 57.9% +/- 3.3% respectively (all P < 0.01). Treated by 3-BrPA combined with L-OHP of the concentration of 0.5 and 1.0 microg/ml for 48 h, the cell proliferation inhibiting rates were increased from 19.2% +/- 6.1% and 32.2% +/- 2.2% to 48.4% +/- 3.2% and 60.5% +/- 4.6% respectively (all P < 0.01). 24 h after the co-cultivation of 3-BrPA of different concentrations, the caspase-3 activity of the LOVO cells was increased along with the increase of the concentration of 3-BrPA (P = 0.000). The PTP opening degrees induced by 3-BrPA and CaCl(2) of the LOVO cells were 40.0% +/- 3.5% and 37.4% +/- 2.3% respectively (P = 0.348). After treated with 100 microml/L 3-BrPA for 1, 3, and 5 h, the DeltaPsim decrease rates of the LOVO cells were 12.7%, 15.4%, and 26.8% respectively. CONCLUSION: HK-II gene may be an effective therapeutic target for gene may be an effective therapeutic target for gene may be an effective therapeutic target for colon cancer.


Assuntos
Hexoquinase/antagonistas & inibidores , Hexoquinase/genética , Piruvatos/farmacologia , Antineoplásicos/farmacologia , Western Blotting , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/enzimologia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Inibidores Enzimáticos/farmacologia , Expressão Gênica , Células HCT116 , Hexoquinase/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Compostos Organoplatínicos/farmacologia , Oxaliplatina , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Chemistry ; 12(30): 7935-41, 2006 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-16874824

RESUMO

We report three crystal structures of a synthetic 5-fluoroalkylporphyrin molecule that was programmed for self-assembly. All the X-ray structures of zincated and free-base porphyrins Zn2 b, Zn5 a, and 2 b revealed rigorous pi-pi stacking and extremely hydrophobic interactions. Other the other hand, the strong aggregation of 5-fluoroalkylporphyrins in solution was also found. Interestingly, the regular nanopore formation of the 5-fluoroalkylporphyrin was visualized by atomic force microscopy (AFM). Importantly, the 5-fluoroalkylporphyrins possess liquid-crystalline properties that were confirmed by using a combination of differential scanning calorimetry (DSC) and polarizing optical microscopy (POM) techniques. By comparison, the self-assembly of non-fluorine-containing porphyrins with similar structure showed much lower aggregation ability, as investigated by NMR techniques. Additionally, no birefringent mesophase was observed for the non-fluorine-containing porphyrin.


Assuntos
Flúor/química , Cristais Líquidos/química , Porfirinas/química , Cristalografia por Raios X , Microscopia de Força Atômica
18.
Carbohydr Res ; 341(13): 2224-32, 2006 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-16839523

RESUMO

The effect of substitution by the fluorine atom at different positions of D-glucose was investigated by quantum chemical calculation of the low-energy conformers. These were obtained through the Random conformational search method. The geometries of conformers were optimized at the RHF/6-31(d) level, then reoptimization and vibrational analysis were performed at the B3LYP/6-31+G(d) level. Single-point energies were calculated at the B3LYP/6-311++G(2d,2p) level. The free energies of solvation in water were calculated utilizing the AM1-SM5.4 solvation model. For all substitution positions, the ring conformation does not change much, and the pyranoid 4C1 conformers are dominant, while variations in the substitution site result in different effects in the network of hydrogen bonds, anomeric effect, the solvation free energy, and the ratio of alpha- and beta-anomers.


Assuntos
Desoxiglucose/química , Flúor/química , Glucose/química , Simulação por Computador , Hidrocarbonetos Fluorados , Ligação de Hidrogênio , Modelos Químicos , Modelos Moleculares , Conformação Molecular , Eletricidade Estática , Estereoisomerismo , Termodinâmica
19.
J Org Chem ; 71(2): 527-36, 2006 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-16408960

RESUMO

[reaction: see text] Electrophilic nitration, formylation or bromination of metalated 5-fluoroalkyl-10,20-diphenylporphyrin (fluoroalkyl = CF3, ClCF2CF2, n-C6F13) proceeded with high regioselectivity, exclusively affording corresponding meso-substituted porphyrins, while the iodination reaction mainly took place at the adjacent beta site giving 2-iodo-10-fluoroalkyl-5,15-diphenylporphyrin. Suzuki, Sonogashira, and trifluoromethylation reactions of the obtained 5-bromo-15-fluoroalkyl-10,20-diphenylporphyrins or 2-iodo-10-fluoroalkyl-5,15-diphenylporphyrins could perform smoothly to give the corresponding various meso- or beta-functionalized fluoroalkylated porphyrin derivatives. Accordingly, two meso-to-meso butadiyne-bridged bisporphyrin dimers and two beta-to-beta butadiyne-linked dimeric porphyrins were prepared by the coupling reactions of 5-ethynyl-15-fluoroalkyl-10,20-diphenylporphyrins and 2-ethynyl-10-fluoroalkyl-5,15-diphenylporphyrins, respectively.

20.
J Chem Theory Comput ; 2(1): 157-65, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26626390

RESUMO

The binding mechanism of iminosugar inhibitor 1-deoxynojirimycin and isofagomine toward ß-glucosidase was studied with nanosecond time scale molecular dynamics. Four different systems were analyzed according to the different protonated states of inhibitor and enzyme (acid/base carboxyl group, Glu166). The simulations gained quite a reasonable result according to the thermodynamic experimental fact. Further conclusions were made including the following: (1) 1-deoxynojirimycin binds with the ß-glucosidase as conjugate acid forms; (2) the slow onset inhibition of isofagomine aims to slow deprotonation of the acid/base carboxyl group which is caused by a nearly zero hydrogen bond interaction between the hydroxyls of the acid/base carboxyl group; and (3) the nucleophile carboxyl group plays an important role when the inhibitor binds with glucosidase.

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