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1.
Small ; 20(4): e2304393, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37712098

RESUMO

Healed defects on photocatalysts surface and their interaction with plasmonic nanoparticles (NPs) have attracted attention in H2 production process. In this study, surface oxygen vacancy (Vo ) defects are created on ZnO (Vo -ZnO) NPs by directly pyrolyzing zeolitic imidazolate framework. The surface defects on Vo -ZnO provide active sites for the diffusion of single Au atoms and as nucleation sites for the formation of Au NPs by the in situ photodeposition process. The electronically healed surface defects by single Au atoms help in the formation of a heterojunction between the ZnO and plasmonic Au NPs. The formed Au/Vo -Au:ZnO-4 heterojunction prolongs photoelectron lifetimes and increases donor charge density. Therefore, the optimized photocatalysts of Au/Vo -Au:ZnO-4 has 21.28 times higher H2 production rate than the pristine Vo -ZnO under UV-visible light in 0.35 m Na2 SO4 and 0.25 m Na2 SO3 . However in 0.35 m Na2 S and 0.25 m Na2 SO3 , the H2 production rate is 25.84 mmole h-1 g-1 . Furthermore, Au/Vo -Au:ZnO-4 shows visible light activity by generating hot carries via induced surface plasmonic effects. It has 48.58 times higher H2 production rate than pristine Vo -ZnO. Therefore, this study infers new insight for defect healing mediated preparation of Au/Vo -Au:ZnO heterojunction for efficient photocatalytic H2 production.

2.
Phytother Res ; 29(3): 381-92, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25414115

RESUMO

Gouania leptostachya DC. var. tonkinensis Pitard. Rhamnaceae is a traditional medicinal plant used in Thailand for treating various inflammatory symptoms. However, no systematic studies have been performed concerning the anti-inflammatory effects or molecular mechanisms of this plant. The immunopharmacological activities of a methanol extract from the leaves and twigs of G. leptostachya (Gl-ME) were elucidated based on the gastritis symptoms of mice treated with HCl/EtOH and the inflammatory responses, such as nitric oxide (NO) release and prostaglandin E2 (PGE2) production, from RAW264.7 cells and peritoneal macrophages. Moreover, inhibitory target molecules were also assessed. Gl-ME dose-dependently diminished the secretion of NO and PGE2 from LPS-stimulated RAW264.7 cells and peritoneal macrophages. The gastritis lesions of HCl/EtOH-treated mice were also attenuated after Gl-ME treatment. The extract (50 and 300 µg/mL) clearly reduced mRNA expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2, nuclear translocation of p65/nuclear factor (NF)-κB, phosphorylation of p65-activating upstream enzymes, such as protein kinase B (AKT), inhibitor of κBα kinase (IKK), and inhibitor of κB (IκBα), and the enzymatic activity of Src. By HPLC analysis, one of the major components in the extract was revealed as resveratrol with NO and Src inhibitory activities. Moreover, this compound suppressed NO production and HCl/EtOH-induced gastric symptoms. Therefore, these results suggest that Gl-ME might be useful as an herbal anti-inflammatory medicine through the inhibition of Src and NF-κB activation pathways. The efficacy data of G. leptostachya also implies that this plant could be further tested to see whether it can be developed as potential anti-inflammatory preparation.


Assuntos
Anti-Inflamatórios/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Extratos Vegetais/farmacologia , Rhamnaceae/química , Estilbenos/farmacologia , Animais , Linhagem Celular , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Gastrite/tratamento farmacológico , Proteínas I-kappa B/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Inibidor de NF-kappaB alfa , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Resveratrol , Tailândia
3.
Toxicol Appl Pharmacol ; 273(3): 659-71, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24161344

RESUMO

A synthetic Militarin analog-1[(2R,3R,4R,5R)-1,6-bis(4-(2,4,4-trimethylpentan-2-yl)phenoxy) hexane-2,3,4,5-tetraol] is a novel derivative of constituents from Cordyceps militaris, which has been used to treat a variety of chronic diseases including inflammation, diabetes, hyperglycemia and cancers. Here, we report for the first time the synthesis of Militarin analog-1 (MA-1) and the apoptotic mechanism of MA-1 against human lung cancer cell lines. Treatment with MA-1 significantly inhibited the viability of 3 human lung cancer cell lines. The inhibition of viability and growth in MA-1-treated A549 cells with an IC50 of 5µM were mediated through apoptosis induction, as demonstrated by an increase in DNA fragmentation, sub-G0/G1-DNA fraction, nuclear condensation, and phosphatidylserine exposure. The apoptotic cell death caused mitochondrial membrane permeabilization through regulation of expression of the Bcl-2 family proteins, leading to cytochrome c release in a time-dependent manner. Subsequently, the final stage of apoptosis, activation of caspase-9/-3 and cleavage of poly (ADP ribose) polymerase, was induced. Furthermore, A549 lung cancer cells were more responsive to MA-1 than a bronchial epithelial cell line (BEAS-2B), involving the rapid generation of reactive oxygen species (ROS), c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK) activation. The pharmacological inhibition of ROS generation and JNK/p38 MAPK exhibited attenuated DNA fragmentation in MA-1-induced apoptosis. Oral administration of MA-1 also retarded growth of A549 orthotopic xenografts. In conclusion, the present study indicates that the new synthetic derivative MA-1 triggers mitochondrial apoptosis through ROS generation and regulation of MAPKs and may be a potent therapeutic agent against human lung cancer.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Glucosídeos/farmacologia , Malatos/farmacologia , Mitocôndrias/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Animais , Caspase 3/genética , Caspase 3/metabolismo , Caspase 9/genética , Caspase 9/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Citocromos c/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Feminino , Glucosídeos/síntese química , Humanos , Concentração Inibidora 50 , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Neoplasias Pulmonares/metabolismo , Malatos/síntese química , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Nus , Mitocôndrias/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Transdução de Sinais , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
4.
Mediators Inflamm ; 2013: 761506, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23970815

RESUMO

Amentoflavone is a biflavonoid compound with antioxidant, anticancer, antibacterial, antiviral, anti-inflammatory, and UV-blocking activities that can be isolated from Torreya nucifera, Biophytum sensitivum, and Selaginella tamariscina. In this study, the molecular mechanism underlying amentoflavone's anti-inflammatory activity was investigated. Amentoflavone dose dependently suppressed the production of nitric oxide (NO) and prostaglandin E2 (PGE2) in RAW264.7 cells stimulated with the TLR4 ligand lipopolysaccharide (LPS; derived from Gram-negative bacteria). Amentoflavone suppressed the nuclear translocation of c-Fos, a subunit of activator protein (AP)-1, at 60 min after LPS stimulation and inhibited the activity of purified and immunoprecipitated extracellular signal-regulated kinase (ERK), which mediates c-Fos translocation. In agreement with these results, amentoflavone also suppressed the formation of a molecular complex including ERK and c-Fos. Therefore, our data strongly suggest that amentoflavone's immunopharmacological activities are due to its direct effect on ERK.


Assuntos
Biflavonoides/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Extratos Vegetais/farmacologia , Taxaceae/metabolismo , Animais , Sobrevivência Celular , Cromatografia Líquida de Alta Pressão , Dinoprostona/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Inflamação , Lipopolissacarídeos/metabolismo , Macrófagos/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-fos/metabolismo , Fator de Transcrição AP-1/metabolismo
5.
ACS Appl Mater Interfaces ; 15(18): 21974-21981, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37000640

RESUMO

To develop a highly efficient solar cell using organometal halide perovskites, its microscale structure control is one of the most important factors because the microstructural defects inside the organometal halide perovskite are harmful to charge carrier flow and, thus, degrade device performance. In this study, we confirmed the existence of large physical gaps at the grain boundary in a methylammonium iodide (MAPbI3, MA = CH3NH3) perovskite with transmission electron microscopy (TEM) analysis and revealed that the physical gap prevents charge carrier flow in the MAPbI3 perovskite. To minimize the physical gap and its negative influences, the grain size of the MAPbI3 perovskite was optimized by increasing the portion of the cubic phase via microstructural phase control using liquid nitrogen (LN2). Through microstructural phase control of the MAPbI3 perovskite, its grain boundaries and physical gap were significantly decreased, and 20.23% power conversion efficiency (PCE) was achieved with a single cation MAPbI3 perovskite solar cell.

6.
Toxicol Appl Pharmacol ; 257(2): 165-73, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21933677

RESUMO

Cordycepin (3-deoxyadenosine), found in Cordyceps spp., has been known to have many therapeutic effects including immunomodulatory, anti-inflammatory, antimicrobial, and anti-aging effects. Moreover, anti-tumor and anti-metastatic effects of cordycepin have been reported, but the mechanism causing cancer cell death is poorly characterized. The present study was designed to investigate whether the mechanisms of cordycepin-induced cell death were associated with estrogen receptor in breast cancer cells. Exposure of both MDA-MB-231 and MCF-7 human breast cancer cells to cordycepin resulted in dose-responsive inhibition of cell growth and reduction in cell viability. The cordycepin-induced cell death in MDA-MB-231 cells was associated with several specific features of the mitochondria-mediated apoptotic pathway, which was confirmed by DNA fragmentation, TUNEL, and biochemical assays. Cordycepin also caused a dose-dependent increase in mitochondrial translocation of Bax, triggering cytosolic release of cytochrome c and activation of caspases-9 and -3. Interestingly, MCF-7 cells showed autophagy-associated cell death, as observed by the detection of an autophagosome-specific protein and large membranous vacuole ultrastructure morphology in the cytoplasm. Cordycepin-induced autophagic cell death has applications in treating MCF-7 cells with apoptotic defects, irrespective of the ER response. Although autophagy has a survival function in tumorigenesis of some cancer cells, autophagy may be important for cordycepin-induced MCF-7 cell death. In conclusion, the results of our study demonstrate that cordycepin effectively kills MDA-MB-231 and MCF-7 human breast cancer cell lines in culture. Hence, further studies should be conducted to determine whether cordycepin will be a clinically useful, ER-independent, chemotherapeutic agent for human breast cancer.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias da Mama/patologia , Desoxiadenosinas/farmacologia , Desoxiadenosinas/uso terapêutico , Receptores de Estrogênio/fisiologia , Apoptose/fisiologia , Autofagia/fisiologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/ultraestrutura , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Feminino , Humanos
7.
Immunopharmacol Immunotoxicol ; 33(1): 90-6, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20476843

RESUMO

Cordyceps species have been known as ethnopharmacologically valuable mushroom in Korea, China, and Japan. This plant has been reported to exhibit a variety of pharmacological activities such as antioxidative, anticancer, anti-inflammatory, antidiabetic, and antiobesity effects. Although numerous pharmacological potentials of Cordyceps spp. have been demonstrated, immunomodulatory effect of Cordyceps bassiana has not been published yet. To evaluate its immunomodulatory activity, macrophages activated by lipopolysaccharide (LPS) were employed and the production of interleukin-12 (IL-12) was explored in terms of understanding its molecular inhibitory mechanism. Seventy percent of ethanol extract from Cordyceps bassiana (Cb-EE) was able to suppress the expression of IL-12, a cytokine regulating interferon-γ (IFN-γ)-producing T helper type 1 (Th1) polarization response, at the transcriptional levels. The inhibitory effect of Cb-EE seemed to be due to activator protein-1 (AP-1) translocation inhibition, according to immunoblotting analysis with nuclear fraction and luciferase assay. In agreement with this, Cb-EE strongly suppressed the phosphorylation of p38, a prime signal to stimulate AP-1 translocation and IL-12 production, strongly suppressed by SB203580, a p38 inhibitor. Furthermore, this extract also suppressed IFN-γ production in both phytohemaglutinin A and LPS-activated splenocytes. Our results suggest that Cb-EE can be applied as a Th1 response regulatory herbal medicine.


Assuntos
Cordyceps/química , Fatores Imunológicos/farmacologia , Interleucina-12/biossíntese , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/imunologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/fisiologia , Etanol , Células HEK293 , Humanos , Immunoblotting , Fatores Imunológicos/isolamento & purificação , Interferon gama/biossíntese , Interleucina-12/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Luciferases/genética , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/genética , NF-kappa B/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Baço/citologia , Baço/efeitos dos fármacos , Baço/imunologia , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/fisiologia , Transfecção
8.
Pharmazie ; 66(1): 58-62, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21391436

RESUMO

Cordyceps species have been known since long as a multi-utility ethnomedicinal herbal in Korea, China and Japan. It has been reported to exhibit a number of properties such as anti-oxidative, anti-cancer, antiinflammatory, anti-diabetic, and anti-obesity effects. In a previously conducted study, we had demonstrated that the ethanol extract of Cordyceps bassiana was able to suppress the production of interleukin (IL)-12 and interferon (IFN)-gamma in macrophages and T lymphocytes. In this study, we were able to further explore the molecular basis of its inhibitory mechanism using a butanol fraction of this herbal (Cb-BF) preparation. Similarly, this fraction also blocked the expression of cytokines such as IL-12 and tumor necrosis factor (TNF)-alpha as well as the proliferation of splenic lymphocytes and their production of IFN-gamma but not IL-4. Cb-BF suppressed the luciferase activities that are mediated by nuclear factor (NF)-kappaB, activator protein (AP)-1, and signal transducers and activators of transcription (STAT)-1. In agreement with this, these fractions diminished the translocation of the transcription factors into the nucleus. The study also demonstrated that the upstream signaling events for the activation of these factors such as spleen tyrosine kinase (Syk), janus kinase (JAK)-2, and extracellular signal-regulated kinase (ERK) were suppressed. Therefore, these results suggest that the butanol extract of Cordyceps bassiana may contain more than one active component capable of inhibiting the inflammatory signaling cascade and this can be considered as a potential candidate for treatment of diseases that require suppression of immune system.


Assuntos
Cordyceps/química , Citocinas/antagonistas & inibidores , Citocinas/biossíntese , Animais , Western Blotting , Butanóis , Corantes , Genes Reporter/efeitos dos fármacos , Humanos , Interferon gama/biossíntese , Interleucina-12/biossíntese , Interleucina-4/biossíntese , Lipopolissacarídeos/farmacologia , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Extratos Vegetais/farmacologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Transdução de Sinais/efeitos dos fármacos , Solventes , Baço/citologia , Baço/efeitos dos fármacos , Sais de Tetrazólio , Tiazóis , Fatores de Transcrição , Fator de Necrose Tumoral alfa/biossíntese , Proteínas Quinases p38 Ativadas por Mitógeno/biossíntese
9.
Adv Mater ; 33(40): e2101574, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34402119

RESUMO

In response to the Comment on article "Self-Organized Superlattice and Phase Coexistence inside Thin Film Organometal Halide Perovskite", it is suggested that the facts that the existence of hexagonal PbI2 is discrepant in 3D crystallographic interpretation and that observation of ( 0 1 ¯ 0 ) and (100) reflections occurs in general, together make the challenges that were raised in the published Comment less convincing. In addition, a new transmission electron microscopy method using direction-selective electron beam damage of the organometal halide perovskite is disclosed.

10.
Biol Pharm Bull ; 33(1): 128-32, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20045950

RESUMO

Coffee is a popular beverage worldwide with various nutritional benefits. Diterpene cafestol, one of the major components of coffee, contributes to its beneficial effects through various biological activities such as chemopreventive, antitumorigenic, hepatoprotective, antioxidative and antiinflammatory effects. In this study, we examined the precise molecular mechanism of the antiinflammatory activity of cafestol in terms of prostaglandin E(2) (PGE(2)) production, a critical factor involved in inflammatory responses. Cafestol inhibited both PGE(2) production and the mRNA expression of cyclooxygenase (COX)-2 from lipopolysaccharide (LPS)-treated RAW264.7 cells. Interestingly, this compound strongly decreased the translocation of c-Jun into the nucleus and AP-1 mediated luciferase activity. In kinase assays using purified extracellular signal-regulated kinase 2 (ERK2) or immunoprecipitated ERK prepared from LPS-treated cells in the presence or absence of cafestol, it was found that this compound can act as an inhibitor of ERK2 but not of ERK1 and mitogen-activated protein kinase kinase 1 (MEK 1). Therefore our data suggest that cafestol may be a novel ERK inhibitor with AP-1-targeted inhibitory activity against PGE(2) production in LPS-activated RAW264.7 cells.


Assuntos
Café/química , Dinoprostona/biossíntese , Diterpenos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Macrófagos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Fator de Transcrição AP-1/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Linhagem Celular , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Lipopolissacarídeos , Luciferases/metabolismo , MAP Quinase Quinase 1/metabolismo , Macrófagos/metabolismo , Camundongos , RNA Mensageiro/metabolismo
11.
Pharm Res ; 26(10): 2280-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19629651

RESUMO

PURPOSE: Present study was undertaken to gain insights into the mechanism of cell cycle arrest by ginseng saponin ginsenoside Rh2 (Rh2) using MCF-7 and MDA-MB-231 breast cancer cells. METHODS: Cell viability and cell cycle distribution were determined by trypan blue dye exclusion assay and flow cytometry, respectively. Immunoblotting was performed to determine changes in protein levels. Knockdown of desired protein was achieved by transfection with small interfering RNA (siRNA). RESULTS: Rh2 treatment significantly inhibited viability of both cells in a concentration-dependent manner, which correlated with G(0)/G(1) phase cell cycle arrest. Rh2-mediated cell cycle arrest was accompanied by down-regulation of cyclin-dependent kinases (Cdk) and cyclins leading to decreased interaction between cyclin D1 and Cdk4/Cdk6 and increased recruitment of p15(Ink4B) and p27(Kip1) to cyclin D1/Cdk4 and cyclin D1/Cdk6 complexes. In addition, Rh2 treatment markedly reduced the levels of phosphorylated retinoblastoma protein (P-Rb) and decreased transcriptional activity of E2F1 in luciferase reporter assay. Rh2-induced cell cycle arrest was significantly attenuated by knockdown of p15(Ink4B) and/or p27(Kip1) proteins. CONCLUSIONS: Rh2-mediated cell cycle arrest in human breast cancer cells is caused by p15(Ink4B) and p27(Kip1)-dependent inhibition of kinase activities of G(1)-S specific Cdks/cyclin complexes.


Assuntos
Neoplasias da Mama/enzimologia , Inibidor de Quinase Dependente de Ciclina p15/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Quinases Ciclina-Dependentes/antagonistas & inibidores , Fase G1/fisiologia , Ginsenosídeos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p15/deficiência , Inibidor de Quinase Dependente de Ciclina p27/genética , Quinases Ciclina-Dependentes/metabolismo , Relação Dose-Resposta a Droga , Feminino , Fase G1/efeitos dos fármacos , Técnicas de Silenciamento de Genes/métodos , Ginsenosídeos/química , Ginsenosídeos/uso terapêutico , Humanos , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
12.
ACS Appl Mater Interfaces ; 11(15): 14222-14228, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30912424

RESUMO

Stretchable alternating-current electroluminescent (ACEL) devices are required due to their potential in wearable, biomedical, e-skin, robotic, lighting, and display applications; however, one of the main hurdles is to achieve uniform electroluminescence with an optimal combination of transparency, conductivity, and stretchability in electrodes. We therefore propose a fabrication scheme involving strategically combining two-dimensional graphene layers with a silver nanowire (Ag NW)-embedded PEDOT:PSS film. The developed hybrid electrode overcomes the limitations of commonly known metallic NWs and ionic conductor-based electrodes for ACEL applications. Furthermore, the potential of the hybrid electrode is realized in demonstrating large-area stretchable ACEL devices composed of an 8 × 8 passive array. The prototype ACEL passive array demonstrates efficient and uniform electroluminescence under high levels of mechanical deformation such as bending, rolling, twisting, and stretching.

13.
Eur J Pharmacol ; 597(1-3): 64-9, 2008 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-18782572

RESUMO

Percutaneous transluminal coronary angioplasty (PTCA) is a common procedure for treating atherosclerosis, but its efficacy is limited because of the occurrence of restenosis within 3-6 months after angioplasty. Restenosis is induced by the remodeling of the vessel wall and/or the accumulation of cells and extracellular matrix (ECM) in the intimal layer. Therefore, the matrix metalloproteinase (MMP) system may be a potential therapeutic target for the treatment of restenosis or atherosclerosis. Cordycepin is reported to possess many pharmacological activities including immunological stimulating, anti-cancer, antioxidant, and anti-inflammatory activities. The effect of cordycepin on restenosis has not yet been clearly elucidated. Therefore, in the present study, we tested the role of cordycepin on the MMP system in vascular smooth muscle cells. In the carotid artery of a balloon-injured Sprague-Dawley (SD) rat, neointimal formation was reduced by treatment with cordycepin (20 microM/day, i.p), which inhibited the proliferation of rat aortic smooth muscle cells (RaoSMCs). To investigate the mechanism by which cordycepin inhibits the remodeling of the vessel wall and/or the accumulation of cells and ECM, we examined the activation of MMP systems in collagen type I-activated RaoSMCs. Cordycepin markedly inhibited the activation of MMP-2 and -9 as well as the expression of extracellular matrix metalloproteinase inducer (EMMPRIN) in a dose-dependent manner in collagen type I-activated RaoSMCs. Moreover, cordycepin suppressed cycloxygenase-2 (COX-2) expression related to hyperplasia of RAoSMCs. Taken together, these data suggest that cordycepin may induce antiproliferation in RAoSMCs via the modulation of vessel wall remodeling. Therefore, cordycepin may be a potential therapeutic approach to treat restenosis.


Assuntos
Fármacos Cardiovasculares/farmacologia , Lesões das Artérias Carótidas/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Desoxiadenosinas/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Animais , Basigina/metabolismo , Lesões das Artérias Carótidas/enzimologia , Lesões das Artérias Carótidas/etiologia , Lesões das Artérias Carótidas/patologia , Cateterismo/efeitos adversos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Colágeno Tipo I/metabolismo , Ciclo-Oxigenase 2/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Humanos , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Músculo Liso Vascular/enzimologia , Músculo Liso Vascular/lesões , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/enzimologia , Miócitos de Músculo Liso/patologia , Ratos , Ratos Sprague-Dawley
14.
ACS Appl Mater Interfaces ; 10(31): 26293-26302, 2018 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-30016061

RESUMO

Dual-source vapor-phase deposition enables low-temperature fabrication of high-performance planar structure perovskite (CH3NH3PbI3) solar cells (PSCs), applicable in tandem devices or for industrial production with high homogeneity. Herein, we report low-temperature fabrication of high-efficiency PSCs by dual-source vapor-phase deposition and significance of TiO2 surface modification with [6,6]-phenyl C61 butyric acid methyl ester (PCBM) on cell performance. Co-evaporation of PbI2 and CH3NH3I, as confirmed by X-ray diffraction and high-resolution transmission electron microscopy analyses, results in CH3NH3PbI3 layers with a well-crystallized tetragonal phase formed on both TiO2 and TiO2/PCBM electron-transport layers (ETLs). The devices with PCBM interlayer between TiO2 and CH3NH3PbI3 showed remarkably higher performance than those with TiO2 only, which was attributed to enhance charge extraction and reduced recombination at the TiO2/PCBM/CH3NH3PbI3 interface. The devices composed of evaporated CH3NH3PbI3 on top of the TiO2/PCBM and [2,2',7,7'-tetrakis( N, N-di- p-methoxyphenyl-amine)-9,9'-spirobifluorene] (Spiro-OMeTAD) as hole-transport material demonstrated power conversion efficiencies of 17.1% (reverse scan) and 13.4% (forward scan) with stabilized efficiency of over 16%, which is, to the best of our knowledge, the highest efficiency reported for evaporated perovskite solar cells using low-temperature fabrication method involving compact TiO2 layer as ETL. Furthermore, we show that this process can be used to deposit a CH3NH3PbI3 layer on top of a textured silicon substrate, which is the first step for preparing perovskite-silicon tandem devices with enhanced antireflection and light-trapping properties.

15.
Adv Mater ; 30(8)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29318666

RESUMO

Organometal halide perovskites have attracted widespread attention as the most favorable prospective material for photovoltaic technology because of their high photoinduced charge separation and carrier transport performance. However, the microstructural aspects within the organometal halide perovskite are still unknown, even though it belongs to a crystal system. Here direct observation of the microstructure of the thin film organometal halide perovskite using transmission electron microscopy is reported. Unlike previous reports claiming each phase of the organometal halide perovskite solely exists at a given temperature range, it is identified that the tetragonal and cubic phases coexist at room temperature, and it is confirmed that superlattices composed of a mixture of tetragonal and cubic phases are self-organized without a compositional change. The organometal halide perovskite self-adjusts the configuration of phases and automatically organizes a buffer layer at boundaries by introducing a superlattice. This report shows the fundamental crystallographic information for the organometal halide perovskite and demonstrates new possibilities as promising materials for various applications.

16.
J Ethnopharmacol ; 114(3): 307-15, 2007 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-17936530

RESUMO

The mushroom Phellinus linteus has been known to exhibit potent biological activity. In contrast to the immuno-potentiating properties of Phellinus linteus, the anti-inflammatory properties of Phellinus linteus have rarely been investigated. Recently, ethanol extract and n-BuOH fractions from Phellinus linteus were deemed most effective in anti-inflammatory activity in RAW 264.7 macrophages. The regulatory mechanisms of Phellinus linteus butanol fractions (PLBF) on the pharmacological and biochemical actions of macrophages involved in inflammation have not been clearly defined yet. In the present study, we tested the role of PLBF on anti-inflammation patterns in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. To investigate the mechanism by which PLBF inhibits NO and PGE2 production as well as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression, we examined the activation of IkappaB and MAPKs in LPS-activated macrophages. PLBF clearly inhibited nuclear translocation of NF-kappaB p65 subunits, which correlated with PLBF's inhibitory effects on IkappaBalpha phosphorylation and degradation. PLBF also suppressed the activation of mitogen-activated protein (MAP) kinases including p38 and stress-activated protein kinase/c-Jun NH2-terminal kinase (SAPK/JNK). Furthermore, macrophages stimulated with LPS generated ROS via activation of membrane-bound NADPH oxidase, and ROS played an important role in the activation of nuclear factor-kappaB (NF-kappaB) and MAPKs. We demonstrated that PLBF directly blocked intracellular accumulation of reactive oxygen species in RAW 264.7 cells stimulated with LPS much as the NADPH oxidase inhibitors, diphenylene iodonium, and antioxidant pyrrolidine dithiocarbamate did. The suppression of NADPH oxidase also inhibited NO production and iNOS protein expression. Cumulatively, these results suggest that PLBF inhibits the production of NO and PGE2 through the down-regulation of iNOS and COX-2 gene expression via ROS-based NF-kappaB and MAPKs activation. Thus, PLBF may provide a potential therapeutic approach for inflammation-associated disorders.


Assuntos
Anti-Inflamatórios/farmacologia , Basidiomycota/química , Mediadores da Inflamação/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , NF-kappa B/antagonistas & inibidores , Transporte Ativo do Núcleo Celular , Animais , Linhagem Celular , Dinoprostona/biossíntese , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/biossíntese , Oxirredução , Fosforilação , Espécies Reativas de Oxigênio/metabolismo
17.
J Med Food ; 10(1): 80-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17472471

RESUMO

Inonotus obliquus (Pers.:Fr.) Pil. is a white rot fungus that belongs to the family Hymenochaetaceae of Basidiomycetes. Extracts and fractions of this fungus have been known to have biological activities, including antimutagenic, anticancer, antioxidative, and immunostimulating effects. Recently, there have been reports that the anti-inflammatory and antinociceptive properties of the methanol extract of I. obliquus may be due to the inhibition of inducible nitric oxide (NO) synthase (iNOS) and cyclooxygenase-2 (COX-2) expression via the down-regulation of nuclear factor kappaB (NF-kappaB) binding activity. However, the effects of I. obliquus on Akt and mitogen-activated protein kinase (MAPK) activation of inflammatory mediator production have not yet been elucidated. In the present study, a 70% ethanol extract of I. obliquus (IOE70) showed antioxidative effects. We also tested the ability of the I. obliquus extract to inhibit the inflammatory cascades in lipopolysaccharide (LPS)-induced RAW 264.7 macrophage cells. The NO inhibition of IOE70 was better than that of other ethanol extracts from I. obliquus. To investigate the mechanism by which IOE 70 inhibits NO production and iNOS and COX-2 expression, we examined the activations of IkappaBalpha, Akt, and c-Jun NH(2) -terminal kinase (JNK) in LPS-activated macrophages. IOE70 markedly inhibited the phosphorylation of IkappaBalpha, Akt, and MAPKs in dose-dependent manners in LPS-activated macrophages. Taken together, these experiments demonstrated that IOE70 inhibition of LPS-induced expression of iNOS and COX-2 protein is mediated by Akt and JNK. Based on our findings, the most likely mechanism that can account for this biological effect of IOE70 involves the inhibition of NF-kappaB through the phosphatidylinositol 3-kinase/Akt/IkappaB pathway and the inhibition of JNK activation. Thus, IOE70 might have useful clinical applications in the management of inflammatory diseases and may also be useful as a medicinal food.


Assuntos
Anti-Inflamatórios/farmacologia , Basidiomycota/química , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Animais , Linhagem Celular , Inibidores de Ciclo-Oxigenase 2/farmacologia , Inibidores Enzimáticos/farmacologia , Etanol , Expressão Gênica/efeitos dos fármacos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/genética , Fosforilação/efeitos dos fármacos , RNA Mensageiro/análise
18.
J Colloid Interface Sci ; 486: 287-295, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27721077

RESUMO

Reduced graphene oxide (rGO)/thorn-like TiO2 nanofiber (TTF) aerogels, or GTTF aerogels, with different TTF weight ratios were successfully prepared by electrospinning, silica etching and hydrothermal combination method. During the hydrothermal reaction, the rGO nanosheets and TTF self-assembled into three-dimensional (3D) interconnected networks, in which the TTF is loaded onto the rGO nanosheets. The electrochemical performance of the GTTF aerogels was assessed using cyclic voltammetry and galvanostatic charge-discharge measurements in a 1M aqueous Na2SO4 electrolyte. The TTF-to-rGO ratio of the aerogel material significantly affected the electrochemical performance of the aerogel electrodes, and the GTTF aerogels prepared with 20wt% TTF (denoted GTTF-20) exhibited excellent electrochemical performance. The maximum specific capacitance of this aerogel electrode was 178F/g at a current density of 1A/g. The GTTF-20 aerogel also exhibited good electrochemical stability with a capacitance degradation of less than 10% after 3000cycles. We can deduce that the electrochemical performance of the as-prepared aerogels may be enhanced by increasing the chemical interactions between rGO and TiO2. The results indicate that the GTTF aerogels show enormous potential for application in energy storage devices.

19.
Sci Rep ; 7(1): 14685, 2017 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-29089627

RESUMO

Highly transparent and stretchable Ag nanowire (NW)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) hybrid electrodes were prepared on stretchable polyurethane substrates by using simple and cost-effective brush painting technique. The optimized Ag NW/PEDOT:PSS hybrid electrode showed a sheet resistance of 19.7 Ohm/square and a high optical transmittance of 88.64% comparable to conventional ITO electrode. It was found that shear stress of the paintbrush led to an effective lateral alignment of the Ag NWs into the PEDOT:PSS matrix during brush painting process. In addition, we investigated mechanical properties of the brush painted Ag NW/PEDOT:PSS hybrid electrode using inner/outer bending test, stretching tests, twisting test and rolling test in detail. The optimized brush painted Ag NW/PEDOT:PSS electrode showed a higher strain (~30%) than brush painted Ag NW or sputtered ITO electrode. Furthermore, we demonstrated the outstanding stretchability of brush painted Ag NW/PEDOT:PSS hybrid electrode in two applications: stretchable interconnectors and stretchable electrodes for stretchable and wearable thin film heaters. These results provide clear evidence for its potential and widespread applications in next-generation, stretchable displays, solar cells, and electronic devices.

20.
Sci Rep ; 7: 46739, 2017 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-28436426

RESUMO

We report on semi-transparent stretchable Ag films coated on a wavy-patterned polydimethylsiloxane (PDMS) substrate for use as stretchable electrodes for stretchable and transparent electronics. To improve the mechanical stretchability of the Ag films, we optimized the wavy-pattern of the PDMS substrate as a function of UV-ozone treatment time and pre-strain of the PDMS substrate. In addition, we investigated the effect of the Ag thickness on the mechanical stretchability of the Ag electrode formed on the wavy-patterned PDMS substrate. The semi-transparent Ag films formed on the wavy-patterned PDMS substrate showed better stretchability (strain 20%) than the Ag films formed on a flat PDMS substrate because the wavy pattern effectively relieved strain. In addition, the optical transmittance of the Ag electrode on the wavy-patterned PDMS substrate was tunable based on the degree of stretching for the PDMS substrate. In particular, it was found that the wavy-patterned PDMS with a smooth buckling was beneficial for a precise patterning of Ag interconnectors. Furthermore, we demonstrated the feasibility of semi-transparent Ag films on wavy-patterned PDMS as stretchable electrodes for the stretchable electronics based on bending tests, hysteresis tests, and dynamic fatigue tests.

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