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1.
Nano Lett ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607382

RESUMO

We propose a band engineering scheme on the biphenylene network, a newly synthesized carbon allotrope. We illustrate that the electronic structure of the biphenylene network can be significantly altered by controlling conditions affecting the symmetry and destructive interference of wave functions through periodic fluorination. First, we investigate the mechanism for the appearance of a type-II Dirac fermion in a pristine biphenylene network. We show that the essential ingredients are mirror symmetries and stabilization of the compact localized eigenstates via destructive interference. While the former is used for the band-crossing point along high symmetry lines, the latter induces highly inclined Dirac dispersions. Subsequently, we demonstrate the transformation of the biphenylene network's type-II Dirac semimetal phase into various Dirac phases such as type-I Dirac, gapped type-II Dirac, and nodal line semimetals through the deliberate disruption of mirror symmetry or modulation of destructive interference by varying the concentration of fluorine atoms.

2.
Arch Pharm Res ; 34(4): 625-33, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21544728

RESUMO

Lung malignancy is a major cause of human mortality. As such, safe pharmacological agents that can detect lung cancer are urgently required. Magnolol has been reported to have anticancer property. However, it is still unclear whether magnolol induces apoptosis of lung carcinoma cells. In this study, magnolol inhibited cell growth, increased lactate dehydrogenase release, and modulated cell cycle in human lung carcinoma A549 cells. Magnolol induced the activation of caspase-3 and cleavage of Poly-(ADP)-ribose polymerase, and decreased the expression level of nuclear factor-κB/Rel A in the nucleus. In addition, magnolol inhibited basic fibroblast growth factor-induced proliferation and capillary tube formation of human umbilical vein endothelial cells. These data indicate that magnolol is a potential candidate for treating of human lung carcinoma.


Assuntos
Antineoplásicos/farmacologia , Compostos de Bifenilo/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Lignanas/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Compostos de Bifenilo/uso terapêutico , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Caspase 3/metabolismo , Técnicas de Cultura de Células , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Citometria de Fluxo , Humanos , Lignanas/uso terapêutico , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , NF-kappa B/biossíntese , Neovascularização Patológica/tratamento farmacológico , Poli(ADP-Ribose) Polimerases/metabolismo
3.
Immunopharmacol Immunotoxicol ; 32(2): 258-64, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20100031

RESUMO

BACKGROUND AND AIM: Corydalis heterocarpa is a biennial herb in South Korea, with spikes of yellow flowers. It has been used for as a folk medicine to cure travail and spasm. However, studies on this herb and its secondary metabolites have rarely been reported. In the present study, we isolated secondary metabolite libanlibanoridin from Corydalis heterocarpa. We have also examined the effect of libanoridin on the inflammatory cytokines production in phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore, A2318 stimulated human mast cell line, HMC-1. PMA plus A23187 significantly increased interleukin (IL)-1beta, IL-6, IL-8, and tumor necrosis factor (TNF)-alpha production compared to media control (P < 0.05). RESULTS: We report that treatment with libanlibanoridin can inhibit PMA plus A23187-induced IL-1beta, IL-6, IL-8, and TNF-alpha production in a concentration-dependent manner with IC50 of 0.002, 1.38, 1.48, and 0.36 mug/ml, respectively. Maximal inhibition rates of IL-1beta, IL-6, IL-8, and TNF-alpha production by libanlibanoridin were about 117.5%, 86.22%, 86.41%, and 90.74%, respectively. libanoridin inhibits the mRNA expression of IL-1beta, IL-6, IL-8, and TNF-alpha. libanoridin also inhibits the expression of cyclooxygenase-2. CONCLUSION: These results indicate that libanlibanoridin may be helpful in regulating mast cell-mediated allergic inflammatory response.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Cumarínicos/farmacologia , Citocinas/imunologia , Mastócitos/efeitos dos fármacos , Anti-Inflamatórios não Esteroides/isolamento & purificação , Western Blotting , Calcimicina/farmacologia , Técnicas de Cultura de Células , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Corydalis/química , Cumarínicos/isolamento & purificação , Citocinas/biossíntese , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Humanos , Hipersensibilidade/imunologia , Hipersensibilidade/prevenção & controle , Concentração Inibidora 50 , Ionóforos/farmacologia , Mastócitos/imunologia , Medicina Tradicional Coreana , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Acetato de Tetradecanoilforbol/farmacologia
4.
In Vitro Cell Dev Biol Anim ; 46(1): 72-81, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19789931

RESUMO

Ailanthus altissima swingle (ailanthic cortex, AAS) has been used as a traditional medicine for fever, bleeding, infection, and inflammation for many years in Korea. However, its mechanisms have not been examined. In the present study, we investigate the effect of AAS on the mast-cell-mediated allergic and inflammatory reaction using in vivo and in vitro models and elucidate its molecular mechanisms. AAS significantly inhibited compound 48/48-induced edema and systemic anaphylaxis. AAS significantly inhibited passive cutaneous anaphylaxis. AAS inhibited histamine release from rat peritoneal mast cells (RPMCs) in a dose-dependent manner. Moreover, AAS significantly inhibited production of inflammatory cytokines, tumor necrosis factor (TNF), interleukin (IL)-6, and IL-8 on the phorbol 12-myristate 13-acetate and calcium ionophore A23187 (PMACI)-stimulated human mast cell line, HMC-1 cells. AAS inhibits the IgE or stem cell factor-induced TNF production on RPMCs. In activated HMC-1 cells, the expression level of NF-kappaB/Rel A protein increased in the nucleus, whereas the level of NF-kappaB/Rel A in the nucleus was decreased by AAS treatment. In addition, AAS inhibited the PMACI-induced IkappaBalpha degradation. In conclusion, the present results indicate that AAS has potent anti-anaphylactic and anti-inflammatory properties.


Assuntos
Ailanthus/química , Anafilaxia/tratamento farmacológico , Anafilaxia/imunologia , Citocinas/biossíntese , Mediadores da Inflamação/metabolismo , NF-kappa B/metabolismo , Extratos Vegetais/uso terapêutico , Animais , Edema/patologia , Liberação de Histamina/efeitos dos fármacos , Humanos , Masculino , Mastócitos/efeitos dos fármacos , Mastócitos/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Fitoterapia , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , p-Metoxi-N-metilfenetilamina
5.
Biol Pharm Bull ; 32(6): 1027-31, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19483309

RESUMO

In the present study, we extracted Corydalis heterocarpa with various solvents in order to find the bioactive constituents that demonstrated anti-inflammatory effects. We isolated the active compound, Columbianetin. Anti-inflammatory effect of Columbianetin has been reported but the precise effects of Columbianetin in experimental models have remained unknown. In the present study, we investigate the effect of Columbianetin on the production of histamine, interleukin (IL)-1beta, IL-6, IL-8, and tumor necrosis factor (TNF)-alpha and expression of cyclooxygenase-2 (COX-2) by using the human mast cell line (HMC-1). Various concentrations of Columbianetin were treated before the activation of HMC-1 cells with phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore, A23187. PMA plus A23187 significantly increased IL-1beta, IL-6, IL-8, and TNF-alpha production compared with media control (p<0.05). We also show that the increased cytokines IL-1beta, IL-6, IL-8, and TNF-alpha level was significantly inhibited by Columbianetin in a dose-dependent manner (p<0.05). Maximal inhibition rates of IL-1beta, IL-6, IL-8, and TNF-alpha production by Columbianetin were about 102.6%, 101.1%, 95.8%, and 103.9%, respectively. Columbianetin inhibited expression of COX-2. In addition, the effect of Columbianetin was investigated on the histamine release from HMC-1 stimulated by substance P, which promotes histamine release. Columbianetin also inhibited the histamine release by substance P. In conclusion, these results indicate that Columbianetin may be helpful in regulating mast cell-mediated allergic inflammatory responses.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Furocumarinas/farmacologia , Mastócitos/efeitos dos fármacos , Anti-Inflamatórios não Esteroides/isolamento & purificação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Corydalis/química , Ciclo-Oxigenase 2/biossíntese , Furocumarinas/isolamento & purificação , Liberação de Histamina/efeitos dos fármacos , Humanos , Interleucinas/biossíntese , Mastócitos/imunologia , Mastócitos/metabolismo , Fator de Necrose Tumoral alfa/biossíntese
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