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1.
ACS Appl Mater Interfaces ; 14(9): 11873-11882, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35192341

RESUMO

A new generation of compact and high-speed electronic devices, based on carbon, would be enabled through the development of robust gate oxides with sub-nanometer effective oxide thickness (EOT) on carbon nanotubes or graphene nanoribbons. However, to date, the lack of dangling bonds on sp2 oriented graphene sheets has limited the high precursor nucleation density enabling atomic layer deposition of sub-1 nm EOT gate oxides. It is shown here that by deploying a low-temperature AlOx (LT AlOx) process, involving atomic layer deposition (ALD) of Al2O3 at 50 °C with a chemical vapor deposition (CVD) component, a high nucleation density layer can be formed, which templates the growth of a high-k dielectric, such as HfO2. Atomic force microscopy (AFM) imaging shows that at 50 °C, the Al2O3 spontaneously forms a pinhole-free, sub-2 nm layer on graphene. Density functional theory (DFT) based simulations indicate that the spreading out of AlOx clusters on the carbon surface enables conformal oxide deposition. Device applications of the LT AlOx deposition scheme were investigated through electrical measurements on metal oxide semiconductor capacitors (MOSCAPs) with Al2O3/HfO2 bilayer gate oxides using both standard Ti/Pt metal gates as well as TiN/Ti/Pd gettering gates. In this study, LT AlOx was used to nucleate HfO2 and it was shown that bilayer gate oxide stacks of 2.85 and 3.15 nm were able to achieve continuous coverage on carbon nanotubes (CNTs). The robustness of the bilayer was tested through deployment in a CNT-based field-effect transistor (FET) configuration with a gate leakage of less than 10-8 A/µm per CNT.

2.
Nat Prod Res ; 35(12): 2028-2036, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31496280

RESUMO

One new naturally occurring quinone, 3',4'-dihydroxy-1,2,6-trimethoxy-[1,1'-biphenyl]-4(1H)-one (1), one new diarylpropane, emarginone A (2), and one new neolignan, emarginone B (3), along with eighteen known compounds have been isolated from the chemical investigation of the EtOAc-soluble fraction of the Vaccinium emarginatum whole plant methanolic extract. The new structures were elucidated by combined analysis of spectroscopic analytical methods and comparison with the literature data obtained from known analogues. In addition, the cytotoxicity of compounds 2, 4, and 14-20 against Du145 and PC-3 prostate cancer cell lines using MTT cell proliferation assay was evaluated. Compounds 2 and 19 showed most potent cytotoxicity against Du145 with IC50 values of 7.53 and 6.63 µg/mL, respectively. Furthermore, compounds 2, 17, and 19 also exhibited significant cytotoxicity against PC-3 with IC50 values ranging from 3.44-6.64 µg/mL.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Vaccinium/química , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Estrutura Molecular , Células PC-3 , Fenilpropionatos/química , Fenilpropionatos/farmacologia , Extratos Vegetais/química , Neoplasias da Próstata/patologia , Quinonas/química , Quinonas/farmacologia
3.
Planta Med ; 86(17): 1313-1322, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32645739

RESUMO

Two new Δ12 ursene-type triterpenoid coumaroyl esters (1: and 2: ), one new Δ7,15 isopimarane-type diterpenoid glycoside (20: ), and two new irido-δ-lactone-type iridoids (21: and 22: ), together with 17 known pentacyclic triterpenoids (3:  - 19: ), were isolated during the phytochemical investigation of a methanol extract of the whole plant of Vaccinium emarginatum. Their structures were determined by detailed analysis of standard spectroscopic data (MS, IR, 1D, and 2D NMR) and comparison with data of known analogs. The isolates were evaluated for their cytotoxicity against the PC-3 and Du145 prostate cancer cell lines (as assessed by an MTT cell proliferation assay), as well as for their anti-inflammatory activity via the inhibition of nitric oxide production in lipopolysaccharide-induced murine macrophage RAW 264.7 cells. Among the isolates, the triterpenoid coumaroyl and feruloyl esters (1, 3: , and 4: ) exhibited strong cytotoxicity against PC-3 prostate cancer cells, with 85.6 - 90.2% inhibition at 10.0 µg/mL. The pomolic acid coumaroyl and feruloyl esters (1: and 3: ) also showed moderate anti-inflammatory activity against nitric oxide production in lipopolysaccharide-induced RAW 264.7 cells, with 59.2 (± 1.0) and 47.1% (± 0.2) inhibition at 12.5 µg/mL, respectively.


Assuntos
Vaccinium , Animais , Anti-Inflamatórios/farmacologia , Camundongos , Estrutura Molecular , Óxido Nítrico , Células RAW 264.7 , Terpenos
4.
Fitoterapia ; 141: 104446, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31790770

RESUMO

Phytochemical investigation of methanolic extract of the whole plants of Vaccinium emarginatum allowed for the characterization of one epicatechin derivative (1) that was isolated from a natural source for the first time and three new flavonoids, emarginin A (2), emarginin B (3), and emarginin C (4), together with 11 known compounds (5-15). The structures of compounds 1-4 were elucidated by combination of spectroscopic analysis (MS, IR, and NMR) and by comparison with that of literature analogues. Compounds 1-8 and 11-15 were evaluated for their preliminary in vitro anti-proliferative activity against Du145 and PC-3 prostate cancer cell lines. Among them, compound 15 exhibited most potent cytotoxicity against Du145 and PC-3 cells, with IC50 values of 8.46 and 10.98 µM, respectively. Furthermore, compounds 1-7 were assessed for their anti-inflammatory potential against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 cells. Compound 4 exhibited moderate anti-inflammatory activity, with an IC50 value of 27.99 µM.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Flavonoides/farmacologia , Vaccinium/química , Animais , Antineoplásicos Fitogênicos/química , Flavonoides/química , Humanos , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Camundongos , Modelos Moleculares , Estrutura Molecular , Óxido Nítrico
5.
Am J Chin Med ; 47(7): 1483-1506, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31645126

RESUMO

Adenostemma lavenia is a perennial herb belonging to the Compositae family and is widely distributed in the tropical parts of Asia. It has been widely used as medicine in Taiwan with the whole plant used to treat pulmonary congestion, pneumonia, bacterial infections of the respiratory tract, edema, and inflammation. This study sought to investigate the anti-inflammatory effects of A. lavenia in vitro and in animal models. The anti-inflammatory effects of ethyl acetate fractions of A. lavenia (EAAL) were stimulated with lipopolysaccharide (LPS) murine macrophages (RAW 264.7) and lung injury in mice. EAAL reduced proinflammatory cytokine responses. Preoral EAAL alleviated LPS-induced histological alterations in lung tissue and inhibited the infiltration of inflammatory cells and protein concentrations in bronchoalveolar lavage fluid (BALF). EAAL prevented protein expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2); phosphorylation of IκB-α, MAPKs, and AMP-activated protein kinase (AMPK); and activated anti-oxidant enzymes (catalase, SOD, and GPx), heme oxygenase-1 (HO-1), and nuclear factor E2-related factor 2 (Nrf2) in LPS-stimulated cells and lung tissues. Fingerprinting of EAAL was performed with HPLC to control its quality, and p-coumaric acid was found to be a major constituent. This study suggests that EAAL is a potential therapeutic agent to treat inflammatory disorders.


Assuntos
Proteínas Quinases Ativadas por AMP/imunologia , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/imunologia , Asteraceae/química , Ácidos Cumáricos/administração & dosagem , Medicamentos de Ervas Chinesas/administração & dosagem , Heme Oxigenase-1/imunologia , Fator 2 Relacionado a NF-E2/imunologia , Proteínas Quinases Ativadas por AMP/genética , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/metabolismo , Animais , Anti-Inflamatórios/administração & dosagem , Antioxidantes/metabolismo , Heme Oxigenase-1/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fator 2 Relacionado a NF-E2/genética , Transdução de Sinais/efeitos dos fármacos
6.
Molecules ; 24(18)2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31540241

RESUMO

Phytochemical investigation of the whole plant of Tradescantia albiflora Kunth led to the isolation and characterization of a butanolide, rosmarinosin B (1), that was isolated from natural sources for the first time, a new butenolide, 5-O-acetyl bracteanolide A (2), and a new apocarotenoid, 2ß-hydroxyisololiolide (11), together with 25 known compounds (compounds 3-10 and 12-28). The structures of the new compounds were elucidated by analysis of their spectroscopic data, including MS, 1D, and 2D NMR experiments, and comparison with literature data of known compounds. Furthermore, four butenolides 4a-4d were synthesized as novel derivatives of bracteanolide A. The isolates and the synthesized derivatives were evaluated for their preliminary anti-inflammatory activity against lipopolysaccharide (LPS)-stimulated nitric oxide (NO) production in RAW 264.7 cells. Among them, the synthesized butenolide derivative n-butyl bracteanolide A (4d) showed enhanced NO inhibitory activity compared to the original compound, with an IC50 value of 4.32 ± 0.09 µg/mL.


Assuntos
Anti-Inflamatórios/farmacologia , Furanos/farmacologia , Lipopolissacarídeos/efeitos adversos , Tradescantia/química , 4-Butirolactona/análogos & derivados , Animais , Anti-Inflamatórios/química , Furanos/química , Concentração Inibidora 50 , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Células RAW 264.7
7.
RSC Adv ; 8(55): 31515-31528, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-35548248

RESUMO

Alpinumisoflavone (AIF) is a plant-derived pyranoisoflavone that exhibits a number of pharmacological activities, but the protective effects of AIF against pulmonary inflammation are still unknown. This study aimed to investigate the anti-inflammatory effects and possible molecular mechanisms of AIF in both lipopolysaccharide (LPS)-stimulated macrophages and mice. The results revealed that AIF dramatically suppressed the production of pro-inflammatory mediators [including tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1ß, IL-17, intercellular adhesion molecule-1 (ICAM-1), and nitric oxide (NO)] and increased the levels of anti-oxidative enzymes [including catalase (CAT), heme oxygenase-1 (HO-1), glutathione peroxidase (GPx), and superoxide dismutase (SOD)] both in vitro and in vivo. Additionally, pre-treatment with AIF could not only significantly prevent histopathological changes and neutrophil infiltration but also decreased the expression levels of nuclear factor-kappa B (NF-κB), mitogen-activated protein kinases (MAPKs), and the nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasome, as well as IL-17 production in LPS-induced lung tissues. The anti-inflammatory effects of AIF were mediated by up-regulating anti-oxidative enzymes and suppressing the NF-κB, MAPK, NLRP3 inflammasome and IL-17 signaling pathways. This is the first study to reveal that AIF has a protective effect against LPS-induced lung injury in mice.

8.
Biomedicine (Taipei) ; 7(3): 18, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28840832

RESUMO

Background/Introduction: At present, human diet is replete with sugar and fat. Abnormal metabolism and hyperglycemia or hyperlipidemia in the body induces the development of an overactive and continuous inflammatory response, resulting in obesity and metabolic syndromes, including hypertension, hyperlipidemia, and insulin resistance. Torenia concolor Lindley var. formosana Yamazaki (TC), a perennial creeping herbaceous plant, is a traditional Chinese medicinal herb widely used for the treatment of heat stroke, aching muscles and bones, cold, dysentery, and ambustion. PURPOSE: This study evaluated the influence of TC on inflammation responses and lipid metabolism. METHODS: In this study, ground TC powder was extracted with 95% ethanol. The ethanol was removed by vacuum concentration, and the resulting extract was further extracted with a number of solvents of different polarity to produce four final extracts: an ethanol extract (TCEE), an ethyl acetate extract (TCEAE), an n-butanol extract (TCBUE), and a water extract (TCWE). The anti-inflammatory efficacy of the extracts and their capability for lipid metabolism regulation was then explored. RESULTS: TCEE, TCEAE, and TCBUE exhibited good anti-inflammatory efficacy; TCEAE also simultaneously regulated lipid metabolism. In RAW264.7 cells, these three extracts suppressed the expression of iNOS and IL-6 via the signaling pathway activation of the transcription factor peroxisome proliferator activated receptor γ (PPARγ) and thereby showed anti-inflammatory efficacy. In 3T3-L1 cells, these three extracts promoted lipid metabolism and reduced lipid accumulation through the activation of PPARα and the increased expression of adiponectin, thus demonstrating regulation of lipid metabolism. CONCLUSION: These results indicate that TC possesses anti-inflammatory efficacy and can regulate lipid metabolism through the activation of transcription factor PPARs. We speculate that these nutraceutical effects are attributable to betulin, an active ingredient in this herbal medicine.

9.
Int Immunopharmacol ; 50: 77-86, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28644965

RESUMO

3, 4-Dihydroxybenzalacetone (DBL) is a constituent of Phellinus linteus. This study demonstrated the protective effect of DBL on lipopolysaccharide (LPS)-induced acute lung injuries in mice. Pretreatment with DBL significantly improved LPS-induced histological alterations in lung tissues. In addition, DBL markedly reduced the total cell number, the leukocytes, the protein concentrations, and decreased the release of nitrite, tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6 and the activities of matrix metalloproteinase (MMP)-2 and -9 in the bronchoalveolar lavage fluid. DBL also inhibited the W/D ratio and myeloperoxidase activity in the lung tissues. Western blot analysis indicated DBL efficiently blocked the protein expressions of inducible nitric oxide synthase, cyclooxygenase-2, MMP-2, MMP-9, and the phosphorylation of mitogen-activated protein kinase (MAPK), phosphoinositide-3-kinase (PI3K), AKT, Toll-like receptor 4 (TLR4) and nuclear factor (NF)-κB. Moreover, DBL enhanced the expression of anti-oxidant proteins, such as superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx). Based on our results, DBL might be a potential target for attenuating tissue oxidative injuries and nonspecific pulmonary inflammation.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Butanonas/uso terapêutico , Pulmão/efeitos dos fármacos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Extratos Vegetais/uso terapêutico , Pneumonia/tratamento farmacológico , Lesão Pulmonar Aguda/imunologia , Animais , Butanonas/química , Citocinas/metabolismo , Regulação para Baixo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/imunologia , Pulmão/imunologia , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Óxido Nítrico/metabolismo , Phellinus , Fosfatidilinositol 3-Quinases/metabolismo , Extratos Vegetais/química , Pneumonia/imunologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
10.
Molecules ; 22(4)2017 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-28350337

RESUMO

3,4-Dihydroxybenzalactone (DBL) was isolated from Phellinus linteus (PL), which is a folk medicine possessing various physiological effects. In this study, we used highly metastatic A549 cells to investigate efficacy of DBL inhibition of cancer metastasis and possible mechanisms. The results revealed DBL inhibited migratory and invasive abilities of cancer cells at noncytotoxic concentrations. We found DBL suppressed enzymatic activities, protein expression, and RNA levels of matrix metalloproteinase (MMP)-2 and MMP-9. Western blot results showed DBL decreased phosphoinositide 3-kinase (PI3K)/AKT, phosphorylation status of mitogen-activated protein kinases (MAPKs), and focal adhesion kinase (FAK)/paxillin, which correlated with cell migratory ability. DBL also affected epithelial to mesenchymal transition (EMT)-related biomarkers. In addition, DBL enhanced cytoprotective effects through elevated antioxidant enzymes including heme oxygenase 1 (HO-1), catalase, glutathione peroxidase (GPx), and superoxide dismutase (SOD). Moreover, DBL influenced the nuclear translocation of nuclear factor κB (NFκB), nuclear factor erythroid 2-related factor 2 (Nrf2), Snail, and Slug in A549 cells. Taken together, these results suggested that treatment with DBL may act as a potential candidate to inhibit lung cancer metastasis by inhibiting MMP-2 and -9 via affecting PI3K/AKT, MAPKs, FAK/paxillin, EMT/Snail and Slug, Nrf2/antioxidant enzymes, and NFκB signaling pathways.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Lactonas/química , Neoplasias Pulmonares/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , NF-kappa B/metabolismo , Extratos Vegetais/química , Células A549 , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lactonas/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Metástase Neoplásica , Phellinus , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo
11.
Am J Chin Med ; 45(1): 137-157, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28081626

RESUMO

Scutellaria baicalensis has been widely used as both a dietary ingredient and traditional herbal medicine in Taiwan to treat inflammation, cancer, and bacterial and viral infections of the respiratory tract and gastrointestinal tract. This paper aims to investigate the in vitro and in vivo anti-inflammatory effects of S. baicalensis. In HPLC analysis, the fingerprint chromatogram of the water extract of S. baicalensis (WSB) was established. The anti-inflammatory effects of WSB were inverstigated using lipopolysaccharide (LPS)-stimulated mouse macrophage (RAW264.7) in vitro and LPS-induced lung injury in vivo. WSB attenuated the production of LPS-induced nitric oxide (NO), tumor necrosis factor-alpha (TNF-[Formula: see text], interleukin-[Formula: see text] (IL-1[Formula: see text], and IL-6 in vitro and in vivo. Pretreatment with WSB markedly reduced the LPS-induced histological alterations in lung tissues. Furthermore, WSB significantly reduced the number of total cells and the protein concentration levels in the BALF. WSB blocked protein expression of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), phosphorylation of I[Formula: see text]B-[Formula: see text] protein and MAPKs in LPS-stimulated RAW 264.7 cells and LPS-induce lung injury was also blocked. This study suggests that WSB possesses anti-inflammatory effects in vitro and in vivo, and the results suggested that WSB may be a potential therapeutic candidate for the treatment of inflammatory diseases.


Assuntos
Lesão Pulmonar Aguda/imunologia , Anti-Inflamatórios/farmacologia , Inflamação , Pulmão/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Lesão Pulmonar Aguda/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Ciclo-Oxigenase 2/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Técnicas In Vitro , Interleucina-1beta/efeitos dos fármacos , Interleucina-1beta/imunologia , Interleucina-6/imunologia , Lipopolissacarídeos/farmacologia , Pulmão/imunologia , Pulmão/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Inibidor de NF-kappaB alfa/efeitos dos fármacos , Inibidor de NF-kappaB alfa/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/metabolismo , Fosforilação/efeitos dos fármacos , Scutellaria baicalensis , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Fator de Necrose Tumoral alfa/imunologia
12.
Phys Chem Chem Phys ; 16(9): 3939-45, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24346132

RESUMO

Mesostructured PtRu nanoparticles were electrochemically reduced from their metallic salts directed by a hexagonally packed microemulsion lyotropic liquid-crystalline (MLLC) template. We investigated the structural evolution and atomic distribution of the MLLC-templated mesoporous PtRu nanoparticles (NPs) after electroreduction for varied duration using X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy, complemented by energy-dispersive X-ray spectroscopy (EDS) and field-emission transmission electron microscopy (FE-TEM). The XANES data at the Ru L2,3 and Pt L3 edges show predominantly metallic states of Ru and Pt in the PtRu NPs upon electroreduction. The reduction of Ru(3+) ions in RuCl3 into Ru atoms involves intermediate RuCl-containing complexes. A more rapid reduction of Pt precursors and a release of Ru atoms from Ru precursors in two steps upon electroreduction resulted in aggregation into PtRu nanoparticles, featuring a Pt-rich core, a Ru-rich shell and a varied alloy extent of Ru, deduced from EXAFS data. The complementary results provide insight into the mechanism of growth and atomic distribution of mesostructured PtRu bimetallic nanoparticles from the use of the MLLC-type templates.

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