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1.
Food Chem ; 306: 125615, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31622833

RESUMO

Phycocyanin (PC), a plant-based protein with interesting biological activity, is rarely directly applied in the food industry because it has structural and functional limitations. This study combined ultra-high-pressure (UHP) treatment with glycation to improve PC functionality and explored resulting structural changes using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, scanning electron microscopy, Fourier-transform infrared spectroscopy, circular dichroism, and UV-visible spectroscopy. The UHP treatment obviously improved the speed and degree of glycation and the composite-modified PC (CM-PC) showed high solubility and good emulsifying and foaming performance. Scanning electron microscopy images showed the CM-PC surface was loose and fluffy. Gel electrophoresis, Fourier-transform infrared spectroscopy, and circular dichroism results demonstrated that the content of α-helix decreased from 78.1% in PC to 26.6% in CM-PC, and hydroxyl groups were introduced. UV-visible spectroscopy showed that the mechanism of composite modification involved stretching of the PC and promotion of binding with sugars.


Assuntos
Ficocianina/química , Spirulina/química , Dicroísmo Circular , Eletroforese em Gel de Poliacrilamida , Emulsões/metabolismo , Glicosilação , Pressão , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Exp Ther Med ; 15(3): 2263-2268, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29456633

RESUMO

The present study investigated the molecular mechanism of apoptosis and autophagy in prostate epithelial cells under androgen deprivation (AD). BPH-1 cells were divided into four groups as follows: Control (Cont), AD, autophagy inhibition (AI) and AD + AI groups. Cells in the four groups were treated accordingly, and the level of apoptosis was subsequently measured via flow cytometry. The expression of the microtubule-associated proteins 1A/1B light chain 3 (LC3), caspase-3, poly (ADP-ribose) polymerase 1 (PARP-1) and Beclin-1 proteins of BPH-1 cells was detected at different time points following culture in androgen-deprived medium. Western blotting revealed that the basal levels of the LC3-II protein were detected at 0 h. At 4 h, LC3-II was significantly increased compared with 0 h (P<0.05). Beginning at 20 h, the expression level of the LC3-II protein decreased significantly (P<0.05). Western blotting revealed that beginning at 24 h, the expression level of the PARP-1 protein decreased significantly (P<0.001) and the cleavage fragments of the PARP-1 protein appeared. These results further imply that autophagy serves a cell protective function by mutual inhibition with apoptosis in BPH-1 cells in the removal of androgen conditions. Furthermore, the fragments of the cleaved Beclin-1 protein appeared as 35 and 37 kDa bands. Flow cytometry analysis demonstrated that the rate of cell apoptosis in the AD, AI and AD + AI groups was significantly increased compared with the Cont group (P<0.01). Compared with the AD or the AI groups individually, the rate of cell apoptosis in the AD + AI group was significantly increased (P<0.001). These findings suggest that in the early stage of AD, autophagy has a compensatory function in the cell, whereas in the whole process, autophagy and apoptosis share a mutual antagonism. The Beclin-1-C protein fragment contributed positive feedback to the process of apoptosis, which may be a potential mechanism of AD therapy. Therefore, AD and AI exhibit a synergistic effect to further improve the level of apoptosis.

3.
ACS Appl Mater Interfaces ; 9(8): 7125-7130, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28166623

RESUMO

N-doped graphene (NDG) was investigated for oxygen reduction reaction (ORR) and used as air-electrode catalyst for Zn-air batteries. Electrochemical results revealed a slightly lower kinetic activity but a much larger rate capability for the NDG than commercial 20% Pt/C catalyst. The maximum power density for a Zn-air cell with NDG air cathode reached up to 218 mW cm-2, which is nearly 1.5 times that of its counterpart with the Pt/C (155 mW cm-2). The equivalent diffusion coefficient (DE) of oxygen from electrolyte solution to the reactive sites of NDG was evaluated as about 1.5 times the liquid-phase diffusion coefficient (DL) of oxygen within bulk electrolyte solution. Combined with experiments and ab initio calculations, this seems counterintuitive reverse ORR of NDG versus Pt/C can be rationalized by a spontaneous adsorption and fast solid-state diffusion of O2 on ultralarge graphene surface of NDG to enhance effective ORR on N-doped-catalytic-centers and to achieve high-rate performance for Zn-air batteries.

4.
ACS Appl Mater Interfaces ; 8(40): 26722-26729, 2016 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-27632809

RESUMO

Specific capacity and cyclic performance are critically important for the electrode materials of rechargeable batteries. Herein, a capacity boost effect of Li- and Na-ion batteries was presented and clarified by nitrogen-doped graphene sheets. The reversible capacities progressively increased from 637.4 to 1050.4 mAh g-1 (164.8% increase) in Li-ion cell tests from 20 to 185 cycles, and from 187.3 to 247.5 mAh g-1 (132.1% increase) in Na-ion cell tests from 50 to 500 cycles. The mechanism of the capacity boost is proposed as an electrochemical induced cascading evolution of graphitic N to pyridinic and/or pyrrolic N, during which only these graphitic N adjacent pyridinic or pyrrolic structures can be taken precedence. The original and new generated pyridinic and pyrrolic N have strengthened binding energies to Li/Na atoms, thus increased the Li/Na coverage and delivered a progressive capacity boost with cycles until the entire favorable graphitic N transform into pyridinic and pyrrolic N.

5.
Eur J Pharmacol ; 772: 124-30, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26723515

RESUMO

Eriodictyol, a flavonoid present in citrus fruits, has been reported to have antioxidant and anti-inflammatory effects. In this study, the protective effects of eriodictyol on cisplatin (CP)-induced kidney injury were detected. CP-induced kidney injury model was established by administration of CP (20mg/kg). The results showed that treatment of eriodictyol inhibited the production of blood urea nitrogen (BUN), creatinine, MDA, TBARS, reactive oxygen species (ROS), as well as the production of TNF-α, and IL-1ß in kidney tissues induced by CP. Eriodictyol also up-regulated the activities of SOD, CAT, and GSH-PX decreased by CP. Furthermore, eriodictyol was found to up-regulate the expression of Nrf2/HO-1 and inhibited CP-induced NF-κB activation in kidney tissues. In conclusion, eriodictyol protected against CP-induced kidney injury through activating Nrf2 and inhibiting NF-κB activation.


Assuntos
Cisplatino/efeitos adversos , Citoproteção/efeitos dos fármacos , Flavanonas/farmacologia , Rim/efeitos dos fármacos , Rim/lesões , Estresse Oxidativo/efeitos dos fármacos , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Apoptose/efeitos dos fármacos , Citocinas/metabolismo , Flavanonas/uso terapêutico , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Inflamação/tratamento farmacológico , Rim/metabolismo , Rim/patologia , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo
6.
ACS Appl Mater Interfaces ; 7(47): 26284-90, 2015 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-26548376

RESUMO

Maghemite (γ-Fe2O3) nanocrystalline microspheres (MNMs) self-assembled with 52 nm nanocrystals bridged with FeOOH around grain boundaries were formed by solvothermal reaction and thermal oxidation. The unique architecture endows the MNMs with the lithium storage behavior of a hybrid battery-supercapacitor electrode: initial charge capacity of 1060 mAh g(-1) at the 100 mA g(-1) rate, stable cyclic capacity of 1077.9 mAh g(-1) at the same rate after 140 cycles, and rate capability of 538.8 mAh g(-1) at 2400 mA g(-1). This outstanding performance was attributed to the nanocrystal superiority, which shortens the Li(+) diffusion paths. The mechanism of this hybrid anode material was investigated with experimental measurements and structural analysis. The results indicate that at the first discharge, the MNM nanocrystal microsphere, whose structure can buffer the volume change that occurs during lithiation/delithiation, goes through four stages: Li(+) insertion in cation vacancies, spinel-to-rocksalt transformation, Li(+) intercalation of Li(1.75+x)Fe2O3 nanocrystals, and interfacial Li storage around nanocrystal boundaries. Only the latter two stages were reversible at and after the second charging/discharging cycle, exhibiting the hybrid behavior of a battery-supercapacitor with superior lithium storage.

7.
Bioorg Med Chem Lett ; 24(16): 3877-81, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25001482

RESUMO

A series of pyrimidine-benzimidazol hybrids was synthesized and evaluated for anticancer activity on four human cancer cell lines including MCF-7, MGC-803, EC-9706 and SMMC-7721. Some of the synthesized compounds exhibited moderate to potent activity against MGC-803 and MCF-7. Among them, compounds 5a-b and 6a-b showed most effective activity. Compounds 5b and 6b were more cytotoxic than 5-fluorouracil against all tested four human cancer cell lines, with IC50 values ranging from 2.03 to 10.55 µM and 1.06 to 12.89 µM, respectively. Flow cytometry analysis demonstrated that treatment of MGC-803 with 6b led to cell cycle arrest at G2/M phase accompanied by an increase in apoptotic cell death.


Assuntos
Antineoplásicos/farmacologia , Benzimidazóis/farmacologia , Pirimidinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Benzimidazóis/química , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células MCF-7 , Estrutura Molecular , Pirimidinas/química , Relação Estrutura-Atividade
8.
Bioorg Med Chem Lett ; 24(10): 2388-91, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24745970

RESUMO

In this study we report the synthesis and activity against bovine viral diarrhea virus (BVDV) of a novel series of bicycle δ-sultones containing γ-lactones. BVDV is responsible for major losses in cattle. Some of the synthesized δ-sultones showed pronounced anti-BVDV activity with EC50 values of 0.12-1.0µM and no significant cytotoxicity. Among them, the ortho bromosubstituted derivative 4f (EC50=0.12µM) showed better antiviral activity than other derivatives and was 10 fold more that of than positive control ribavirin (EC50=1.3µM). BVDV is also considered to be a valuable surrogate for the hepatitis C virus (HCV) in antiviral drug studies. The above results provided a novel candidate for the development of anti-HCV agents.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Vírus da Diarreia Viral Bovina/efeitos dos fármacos , Hepacivirus/efeitos dos fármacos , Animais , Bovinos , Modelos Animais de Doenças , Desenho de Drogas
9.
Eur J Med Chem ; 65: 323-36, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23735281

RESUMO

Series of 5-substituted-3,4-diphenylfuran-2-ones were stereoselectively prepared. Their potential anti-proliferative effects on prostate cancer and some of their cyclooxygenases (COXs) inhibitory activities were evaluated. Structure-activity relationship (SAR) data, acquired by substituent modification at the para-position and ortho-position of the C-3 phenyl ring and 5-substituted modification of the central furanone, showed that 3-(2-chloro-phenyl)-4-(4-methanesulfonyl-phenyl)-5-(1-methoxy-ethyl)-5H-furan-2-one (13p) was the most potent compound and could effectively reduce the proliferation of prostate cancer cells (PC3 cell IC50 = 20 µM; PC3 PCDNA cell IC50 = 5 µM; PC3 SKP2 cell IC50 = 5 µM; DU145 cell IC50 = 25 µM). The cell cycle analysis for 13p in DU145 indicated that 13p may induce G1 phase arrest.


Assuntos
Antineoplásicos/farmacologia , Inibidores de Ciclo-Oxigenase/farmacologia , Furanos/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase/síntese química , Inibidores de Ciclo-Oxigenase/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Furanos/síntese química , Furanos/química , Humanos , Masculino , Estrutura Molecular , Neoplasias da Próstata/patologia , Estereoisomerismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
10.
Eur J Med Chem ; 64: 99-110, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23644193

RESUMO

A series of novel 1,2,3-triazole-dithiocarbamate-urea hybrids were designed, synthesized and their antiproliferative activities against four selected human cancer cell lines were evaluated. The results showed that a number of the hybrids exhibited potent activity in selected human cancer cell lines. Among them, compounds 27 and 34 showed broad spectrum anticancer activity with IC50 values ranging from 1.62 to 20.84 µM and 0.76 to 13.55 µM, respectively. Interestingly, compounds 27 and 34, being very potent against MGC-803 cells, exhibited no significant cytotoxicity against normal human embryonic kidney cells at up to 55 µM and 70 µM, respectively. Evidences of cell cycle arrest and apoptosis induction were obtained for the most effective compounds 27 and 34 by means of flow cytometry and microscopic techniques.


Assuntos
Antineoplásicos/farmacologia , Desenho de Drogas , Tiocarbamatos/farmacologia , Triazóis/farmacologia , Ureia/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Tiocarbamatos/química , Triazóis/química , Ureia/análogos & derivados , Ureia/química
11.
Bioorg Med Chem Lett ; 21(10): 3074-7, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21486694

RESUMO

Three series of butenolide-containing dithiocarbamates were designed and synthesized. Their anti-tumor activity in vitro was evaluated. Among them compound I-14 exhibited broad spectrum anti-cancer activity against five human cancer cell lines with IC(50) <30 µM. Structure-activity relationship analysis showed that the introduction of dithiocarbamate side chains on the C-3 position of butenolide was crucial for anti-tumor activity.


Assuntos
4-Butirolactona/análogos & derivados , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Desenho de Drogas , Tiocarbamatos/síntese química , Tiocarbamatos/farmacologia , 4-Butirolactona/química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Relação Estrutura-Atividade , Tiocarbamatos/química
12.
Chirality ; 21(8): 745-50, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18988258

RESUMO

Optically pure (S)-betaxolol and (S)-metoprolol were prepared with an extremely facile and practical method using kinetic resolution of beta-amino alcohols employing HCS as chiral auxiliary. High enantiomeric purity (ee > 99%) was achieved and the synthetic strategy is amenable to industrial scale-up.


Assuntos
Antagonistas Adrenérgicos beta/síntese química , Betaxolol/síntese química , Metoprolol/síntese química , Antagonistas Adrenérgicos beta/química , Betaxolol/química , Cinética , Metoprolol/química , Estrutura Molecular , Estereoisomerismo
13.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 28(6): 537-40, 2008 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-18655565

RESUMO

OBJECTIVE: To explore the action mechanism of the immune active components of sappon wood (SWE) for antagonizing reject reaction by observing the influence of its ethyl acetate extract on mRNA expression of myocardial GrB in rat model of allogenic ectopic cardiac transplantation. METHODS: Animal model of abdominal cardiac ectopic transplantation was established taking Wistar rat as the donor and SD rat as the receptor. The successfully modeled rats were randomly divided into the model group, the SWE group and the CsA group. GrB mRNA expression was detected by RT-PCR method and myocardial pathomorphologic picture was observed in routine. RESULTS: The pathologic changes in the SWE group (23 scores) and the CsA group (14 scores) were milder than in the model group (31 scores), the former two could markedly alleviate the myocardial pathologic injury (P<0.05, P<0.01). The GrB mRNA expression in the model group was 1.3000 +/- 0.1207, the SWE group 0. 7070 +/- 0.1215, and the CsA group 0.6700 +/- 0.0997, respectively; compared with the model group, the latter two could obviously down-regulate the expression of GrB mRNA (P<0.01) and no significant difference was found between the latter two groups (P>0.05). CONCLUSION: SWE could alleviate the pathologic change, down-regulate the mRNA expression of myocardial GrB in allogenic ectopic transplanted myocardium of rats, it is possibly one of the factors for its antagonizing effect against reject reaction.


Assuntos
Acetatos/química , Caesalpinia/química , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Granzimas/genética , Transplante de Coração , Miocárdio/metabolismo , Extratos Vegetais/farmacologia , Animais , Rejeição de Enxerto/tratamento farmacológico , Coração/efeitos dos fármacos , Transplante de Coração/imunologia , Masculino , Modelos Animais , Miocárdio/patologia , Extratos Vegetais/uso terapêutico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Transplante Homólogo
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