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1.
Neurobiol Dis ; 175: 105922, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36371059

RESUMO

Our previous study suggests that hippocampal cysteinyl leukotriene receptor 1 (CysLT1R) could be involved in depression. Herein we hypothesize that CysLT1R may regulate depression by affecting synaptic glutamate cycling based on existence of CysLT1R in the astrocytes that participate in occurrence of depression. We found that CysLT1R expression was significantly increased in the astrocyte of chronic unpredictable mild stress (CUMS)-induced depression-like mice, CysLT1R astrocyte-specific conditional knockout (AcKO) significantly improved depression-like behaviors, as indicated by decreased immobility time in the forced swimming test and tail suspension test and increased sucrose preference in the sucrose preference test, and knockdown of CysLT1R in the astrocyte of dentate gyrus (DG), the region with the most significant increase of CysLT1R in the astrocyte of depression-like mice, produced similar effects. Correspondingly, overexpression of CysLT1R in the astrocyte of DG induced depression-like behaviors in mice. The further study showed that CysLT1R AcKO ameliorated synaptic plasticity impairment, as reflected by increased synapse, LTP and PSD95, and promoted glutamate transporter 1 (GLT-1) expression by inhibiting NF-κB p65 nuclear translocation mediated by ß-arestin2 and clatrhin, subsequently decreased glutamate in synaptic cleft and GluN2B on postsynaptic membrane in depression-like mice. The present study also showed that GLT-1 agonist or NF-κB inhibitor ameliorated depressive-like behaviors induced by overexpression of the astrocyte CysLT1R of DG. Our study demonstrated that astrocyte CysLT1R regulated depression by modulating glutamate synaptic transmission, suggesting that CysLT1R could be a potential target for developing novel drugs of anti-depression.


Assuntos
Astrócitos , Depressão , Ácido Glutâmico , Receptores de Leucotrienos , Transmissão Sináptica , Animais , Camundongos , Astrócitos/metabolismo , Ácido Glutâmico/metabolismo , Hipocampo/metabolismo , NF-kappa B/metabolismo , Estresse Psicológico , Sacarose/metabolismo , Sacarose/farmacologia , Receptores de Leucotrienos/metabolismo , Depressão/metabolismo , Depressão/patologia
2.
Int J Endocrinol ; 2022: 7916327, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36147726

RESUMO

Purpose: Microwave ablation (MWA) is a minimally invasive method for the thermal ablation of benign thyroid nodules and papillary thyroid cancer (PTC) and has shown promising results. The aim of this study was to investigate the impact of MWA on thyroid antibodies and associated influencing factors. Materials and Methods: A total of 119 patients, including 69 with benign thyroid nodules and 50 with PTC, underwent MWA between June 2019 and June 2021. The serum levels of (free) triiodothyronine, (free) thyroxine, thyrotropin, and antibodies against Tg (TGAb), thyrotropin receptors (TRAb), and thyroid peroxidase (TPOAb) were measured during the follow up. Results: One month after ablation, three patients (4.3%) in the benign group had hypothyroidism, and one (1.4%) had hyperthyroidism. Four patients (5.8%) had subclinical hypothyroidism, and two (2.9%) had subclinical hyperthyroidism. Among the PTC patients, two (4%) had hypothyroidism, and one (2%) had hyperthyroidism. Two patients (4%) had subclinical hypothyroidism, and one (2%) had subclinical hyperthyroidism. In the benign group, among patients with normal preablation antibodies, the postablation TGAb abnormal rate was 12.7%, the TPOAb level was 4.8%, and the TRAb level was 0%. Among PTC patients, the postablation TGAb abnormal rate was 11.4%, the TPOAb level was 8.7%, and the TRAb level was 4.0%. The cutoff value of preablation TGAb for predicting postoperative antibody abnormalities was 19.0 IU/mL, while that of TPOAb was 11.4 IU/mL. Conclusions: MWA of thyroid nodules had little influence on thyroid function and antibodies. Elevations in TGAb, TPOAb, and TRAb beyond the normal ranges after MWA may be related to high preablation levels of TGAb and TPOAb.

3.
Bioorg Chem ; 95: 103551, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31911301

RESUMO

Six new guaiane-type sesquiterpenes (1-6), and one monoterpenoid (7) along with five known analogues (8-12), were isolated from the leaves of Artemisia argyi Lévl et Vant. The new compounds were characterized by the basic analysis of the spectroscopic data (HRMS, 1D and 2D NMR), and the absolute configurations were determined by both calculated electronic circular dichroism and DP4 calculations. The inhibitory effects of 1-12 against human gastric adenocarcinoma (AGS) cells were investigated in vitro, among which 1-3 and 8 showed remarkable cytotoxic activity with IC50 values in the range of 6.69-10.25 µM. The results suggested that the variation in the inhibitory activities of the compounds are the result of different substitutions on C-8. In order to rationalize the binding interactions of active compounds with the active site of NF-кB, in silico study was conducted and the results were in complete agreement with the experimental data for cytotoxicity evaluation.


Assuntos
Adenocarcinoma/patologia , NF-kappa B/antagonistas & inibidores , Sesquiterpenos de Guaiano/farmacologia , Neoplasias Gástricas/patologia , Humanos , Análise Espectral/métodos , Células Tumorais Cultivadas
4.
Int Immunopharmacol ; 78: 105947, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31796384

RESUMO

Our previous study has found that zileuton, a selective 5-lipoxygenase (5LO) inhibitor, abrogated lipopolysaccharide-induced depressive-like behaviors and hippocampal neuroinflammation. Herein, we further extended our curiosity to investigate effects of zileuton on stress-induced depressive-like behaviors. Our data indicated that zileuton significantly ameliorated depressive-like behaviors in mice subjected to chronic mild stress (CMS), as shown in the tail suspension test, forced swimming test and novelty-suppressed feeding test. The further studies indicated that zileuton suppressed hippocampal neuroinflammation, evidenced by lower levels of TNF-α, IL-1ß and nuclear NF-κB p65 as well as decreased number of Iba1-positive cells. It also significantly ameliorated hippocampal apoptosis, indicated by deceased number of TUNEL-positive cells, deceased ratio of cleaved caspase-3/procaspase-3 and increased ratio of Bcl-2/Bax. More importantly, zileuton increased the level of synaptic proteins PSD-95 and SYN and the number of NeuN+/BrdU+ cells in the hippocampus. Over all, zileuton alleviated CMS-induced depressive-like behaviors, neuroinflammatory and apoptotic responses, abnormalities of synapse and neurogenesis in the hippocampus, suggesting that it might has beneficial effects on depression.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antidepressivos/uso terapêutico , Depressão/tratamento farmacológico , Encefalite/tratamento farmacológico , Hidroxiureia/análogos & derivados , Fármacos Neuroprotetores/uso terapêutico , Estresse Psicológico/tratamento farmacológico , Animais , Anti-Inflamatórios/farmacologia , Antidepressivos/farmacologia , Apoptose/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Depressão/metabolismo , Depressão/patologia , Encefalite/metabolismo , Encefalite/patologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/patologia , Hidroxiureia/farmacologia , Hidroxiureia/uso terapêutico , Interleucina-1beta/metabolismo , Masculino , Camundongos Endogâmicos ICR , Neurogênese/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Psicológico/metabolismo , Estresse Psicológico/patologia , Sinapses/efeitos dos fármacos , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
5.
Bioorg Chem ; 91: 103118, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31344517

RESUMO

Stauntonia brachyanthera Hand.-Mazz. (SB), reported as a traditional Chinese medicine, displays a wide spectrum of interesting bioactivities, such as anti-inflammatory and analgesia. It is noteworthy that anti-gout effects of the components in SB have been reported. Hence, this study contributes to the prediction of promising active compounds and mechanisms for the treatment of gout. The active compounds with better oral bioavailability, and drug-likeness of SB were selected for further investigation by the approach of network pharmacology, molecular docking, gene ontology (GO) analysis, and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis, respectively. A total of 34 predicted targets and 98 compounds in SB were obtained. Sorted by structure types of compounds, phenylethanoid glycosides exhibited the best anti-gout activity, followed by phenolics and flavonoids. What's more, it was shown in the network analysis that Serine/threonine-protein kinase mTOR (mTOR), Mitogen-activated protein kinase 12 (MAPK12), tumor necrosis factor (TNF-α), Integrin alpha-4 (ITGA4) and Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit gamma (PIK3CG) were the key targets with intensely interaction, which should be attached more attention for further study. The functional enrichment analysis indicated that SB probably produced the anti-gout effects by synergistically regulating many biological pathways, such as MAPK signaling pathway, PI3K-Akt signaling pathway, Toll-like receptor signaling pathway and NOD-like receptor signaling pathway, etc. In addition, C61, C67, C68 and C81 might be promising leading compounds with good molecular docking score. As a consequence, the active constituents and mechanisms based on data analysis were holistically illuminated, which was of vital importance to the development of new drugs for gout.


Assuntos
Anti-Inflamatórios/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Gota/tratamento farmacológico , Magnoliopsida/química , Extratos Vegetais/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Gota/metabolismo , Medicina Tradicional Chinesa , Simulação de Acoplamento Molecular , Estrutura Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estereoisomerismo , Relação Estrutura-Atividade
6.
Cancer Biomark ; 20(4): 581-588, 2017 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-28946557

RESUMO

Tyrosine kinase inhibitors (TKIs), a novel group of target-specific anti lung cancer drugs, have recently been found to resistant to some NSCLC cells which have the T790M EGFR mutation. However, recent investigations on the therapies of resistance to EGFR-TKIs are very limited. Therefore, it is important to develop more effective therapies to reverse EGFR-TKIs resistance. In our present study, erlotinib was used as the TKIs drug and the effects of the erlotinib on cell growth were evaluated. Cell viability and concentration dependent studies were performed using HCI-H1975 and HCI-H1299 cells alone with erlotinib, respectively. Further combined with rituximab, the results showed that erlotinib and rituximab were significantly inhibited the cell growth. Furthermore, the combination of erlotinib and rituximab greatly decreased the expression of p-mTOR and p-EGFR. Additional results from western blotting and immunofluorescence assays demonstrated that the accumulation of rictor was also decreased on MAM. Thus, all these results suggested that EGFR-TKIs combined with CD20 mono-antibody significantly decrease the cell growth of H1975 cells and H1299, with T790M EGFR mutation, and inhibit the localization of the key mTOR pathway proteins to MAM. So, it may be a promising strategy for overcoming EGFR TKI resistance in NSCLC patients.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Membranas Intracelulares/metabolismo , Mitocôndrias/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteína Companheira de mTOR Insensível à Rapamicina/metabolismo , Rituximab/farmacologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Humanos , Concentração Inibidora 50 , Mutação , Fosforilação , Serina-Treonina Quinases TOR/metabolismo
7.
Shanghai Kou Qiang Yi Xue ; 26(1): 42-47, 2017 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-28474065

RESUMO

PURPOSE: To explore the effects and molecular mechanisms of ginsenoside Rg1 on the proliferation and migration of human periodontal ligament cells (HPDLCs) under nicotine stress. METHODS: HPDLCs were isolated and cultured by method of explant cell culture. The cells were cultured under nicotine stress for 7 days, and treated respectively with ginsenoside Rg1 (0.01 µmol/L), ginsenoside Rg1 and LY294002 (PI3K inhibitor, 0.5 µmol/L), ginsenoside Rg1 and Tricirbine (Akt inhibitor, 5 µmol/L), ginsenoside Rg1 and L-NAME (Akt inhibitor, 1 mmol/L) from 3rd day after nicotine stress to 7th day. MTT assay and Transwell assay were used to evaluate the proliferation and migration of HPDLCs in each group. Western blot and quantitative real-time PCR methods were used for testing the changes of PI3K/Akt/eNOS signaling expression. SPSS 20.0 software package was used for statistical analysis. RESULTS: The proliferation and migration were significantly inhibited by nicotine treatment. PI3K levels were upregulated, but Akt1/2 and eNOS levels were remarkedly reduced by nicotine. Ginsenoside Rg1 attenuated the effects of nicotine on proliferation, migration and Akt/eNOS signaling. Tricirbine and L-NAME could reduce the inhibitory effects of ginsenoside Rg1 toward nicotine. CONCLUSIONS: Ginsenoside Rg1 regulates the proliferation and migration of HPDLCs under nicotine stress via Akt/eNOS signaling.


Assuntos
Estimulantes Ganglionares/toxicidade , Ginsenosídeos/metabolismo , Nicotina/toxicidade , Humanos , Óxido Nítrico Sintase Tipo III/metabolismo , Ligamento Periodontal , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Regulação para Cima
8.
Oncol Rep ; 34(3): 1279-88, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26134873

RESUMO

Radiation therapy is the most widely used treatment for patients with cervical cancer. Recent studies have shown that endoplasmic reticulum (ER) stress induces apoptosis and sensitizes tumor cells to radiotherapy, which reportedly induces ER stress in cells. Classical key tumor suppressor p53 is involved in the response to a variety of cellular stresses, including those incurred by ionizing irradiation. A recent study demonstrated that small-molecule RITA (reactivation of p53 and induction of tumor cell apoptosis) increased the radiosensitivity of tumor cells expressing mutant p53 (mtp53). In the present study, we explored the effects and the underlying mechanisms of RITA in regards to the radiosensitivity and ER stress in mtp53-expressing human cervix cancer cells. Treatment with 1 µM of RITA for 24 h before irradiation markedly decreased survival and increased apoptosis in C-33A and HT-3 cells; the effects were not significantly altered by knockdown of p53. In the irradiated C-33A and HT-3 cells, RITA significantly increased the expression of IRE1α, the spliced XBP1 mRNA level, as well as apoptosis; the effects were abolished by knockdown of IRE1α. Transcriptional pulse-chase assays revealed that RITA significantly increased the stability of IRE1α mRNA in the irradiated C-33A and HT-3 cells. In contrast, the same RITA treatment did not show any significant effect on sham-irradiated cells. In conclusion, the present study provides initial evidence that RITA upregulates the expression level of IRE1α by increasing the stability of IRE1α mRNA in irradiated mtp53-expressing cervical cancer cells; the effect leads to enhanced IRE1α/XBP1 ER stress signaling and increased apoptosis in the cells. The present study offers novel insight into the pharmacological potential of RITA in the radiotherapy for cervical cancer.


Assuntos
Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Endorribonucleases/biossíntese , Proteínas de Neoplasias/genética , Proteínas Serina-Treonina Quinases/biossíntese , Fatores de Transcrição/biossíntese , Proteína Supressora de Tumor p53/genética , Neoplasias do Colo do Útero/genética , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Estresse do Retículo Endoplasmático/genética , Endorribonucleases/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Mutação , Proteínas de Neoplasias/biossíntese , Proteínas Serina-Treonina Quinases/genética , Radiação , Tolerância a Radiação , Fatores de Transcrição de Fator Regulador X , Transdução de Sinais/efeitos da radiação , Fatores de Transcrição/genética , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/radioterapia , Proteína 1 de Ligação a X-Box
9.
Zhonghua Jie He He Hu Xi Za Zhi ; 33(2): 123-7, 2010 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-20367953

RESUMO

OBJECTIVE: to investigate the antitumor effects of tumstatin185-191 as a single agent or combination with cisplatin (DDP) on non-small lung cancer (NSCLC) cell lines A549. In addition, the changes of the protein kinase B(Akt) and extracellular regulated protein kinase (ERK) in cultured NSCLC cells treated by tumstatin185-191 and cisplatin were evaluated. METHODS: A549 cells were treated with tumstatin185-191 and cisplatin. Cell viability was assessed using the modified 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell apoptosis was measured by flow cytometry. The activation of Akt and Erk were evaluated by Western blotting. RESULTS: Tumstatin185-191 inhibited the proliferation of A549 and the IC(50) values of tumstatin 185-191 was 73.7 micromol/L. After cotreatment with 20 micromol/L tumstatin185-191, IC(50) values of cisplatin in A549 cells reduced from 5.2 micromol/L to 3.5 micromol/L, while 40 micromol/L tumstatin185-191 reduced from 5.2 micromol/L to 1.4 micromol/L. The early apoptosis rate was (19.34 +/- 0.97)% in the cotreatment group, (12.5 +/- 2.1)% in cisplatin group and (9.6 +/- 1.6)% in tumstatin185-191 group (F = 5.74, P < 0.01). The levels of phospho-Akt (p-Akt) and phospho-ERK (p-ERK) in the A549 cells were remarkably lower after being treated with tumstatin 185-191, while tumstatin 185-191 treatment whether alone, or in combination with cisplatin, had the similar effects on the protein levels of p-Akt and p-ERK in A549 cells. CONCLUSION: our data suggest that tumstatin185-191 might enhance the sensitivity of A549 cells to cisplatin. The effects of promoting apoptosis and downregulation of proliferation induced by tumstatin185-191 may be mediated through inactivation of the Akt and ERK pathways.


Assuntos
Adenocarcinoma/metabolismo , Autoantígenos/farmacologia , Colágeno Tipo IV/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Apoptose , Autoantígenos/administração & dosagem , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cisplatino/administração & dosagem , Cisplatino/farmacologia , Colágeno Tipo IV/administração & dosagem , Humanos , Neoplasias Pulmonares/patologia
10.
Zhonghua Zhong Liu Za Zhi ; 31(8): 577-81, 2009 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-20021943

RESUMO

OBJECTIVE: To investigate the effects and related mechanisms of Tumstatin 185-191 as a single agent or in combination with cisplatin on proliferation and apoptosis in a cisplatin-resistant human lung adenocarcinoma cell line A549-DDP cells. METHODS: A549-DDP cells were treated with Tumstatin185-191 and cisplatin at varying concentrations. Cell viability was assessed by a modified 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. 50% inhibiting concentration (IC(50)) values of the chemotherapeutic drugs were analyzed by MTT assay. Cell apoptosis was measured by flow cytometry. The activation of Akt and ERK was evaluated by Western blotting. RESULTS: Tumstatin185-191 inhibited the proliferation of A549-DDP cells and its IC(50) value was 80.25 micromol/L. After cotreatment with 20 micromol/L Tum185-191, the IC(50) value of cisplatin in A549-DDP cells reduced from 77.16 micromol/L to 57.97 micromol/L, the reverse index was 1.33, while with 40 micromol/L Tumstatin185-191 the IC(50) was reduced from 77.16 to 26.40 micromol/L and the reverse index was 2.92. The early apoptosis rate was 19.5% +/- 1.1% in the cotreatment group, while 13.3% +/- 1.5% in cisplatin group and 10.2% +/- 2.0% in Tum185-191 group (F = 4.09, P < 0.05). The levels of phospho-Akt (p-Akt) and phospho-ERK (p-ERK) in the A549-DDP cells were remarkably lower after treatment with Tumstatin 185-191. The Tumstatin 185-191 treatment alone or in combination with cisplatin had a similar effect on the protein levels of p-Akt and p-ERK in A549-DDP cells. CONCLUSION: Our data suggest that Tumstatin185-191 may promote apoptosis, downregulate proliferation and partly reverse the drug resistance of A549-DDP cells to cisplatin. The effects induced by Tum185-191 may be mediated through inactivation of the Akt and ERK pathways.


Assuntos
Adenocarcinoma/patologia , Apoptose/efeitos dos fármacos , Autoantígenos/farmacologia , Proliferação de Células/efeitos dos fármacos , Colágeno Tipo IV/farmacologia , Neoplasias Pulmonares/patologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Fragmentos de Peptídeos/farmacologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo
11.
Zhonghua Jie He He Hu Xi Za Zhi ; 32(2): 128-32, 2009 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-19567186

RESUMO

OBJECTIVE: To explore the effect of cyclooxygenase-2 on vascular endothelial cell apoptosis induced by cigarette smoke extract. METHODS: Human vascular endothelial cells (ECV-304) were cultured in vitro, and those at the exponential growth phase were studied in experiments. The experiment was completed through 3 steps: (1) ECV-304 cells were cultured with 0.0%, 0.5%, 1.0% and 5.0% CSE for 12 h. (2) ECV-304 cells were exposed to 5.0% CSE for 0, 3, 6, 9, 12 and 24 h. (3) Endothelial cells were treated by 5% CSE, together with different concentrations of selective COX-2 inhibitor celecoxib (0.0, 2.5, 5.0, 10.0, 20.0, 50.0 micromol/L concentrations) for 9 h. The cell apoptosis rate was tested by Hoechst staining and flow cytometry methods, and the expression of COX-2 protein by immunocytochemistry and Western blotting. RESULTS: CSE induced ECV-304 cell apoptosis and COX-2 expression in a dose-dependent manner. The apoptosis rate of ECV-304 cells with 5.0% CSE was the highest (5.40+/-0.39)%. CSE- induced COX-2 expression reached the highest level with 5.0% CSE (206.1+/-15.5), the differences being significant (F=90.03, 159.94, all P<0.05). Furthermore CSE induced both apoptosis rate and COX-2 expression time-dependently, with the apoptosis rate achieving the peak after 24 h (8.87+/-0.41)%, while COX-2 expression reached the highest level at 9 h. The selective COX-2 inhibitor celecoxib inhibited COX-2 protein expression partially and augmented cell apoptosis induced by CSE. CONCLUSIONS: CSE induces endothelial cell apoptosis and increases the expression of COX-2 protein in vascular endothelial cells. Celecoxib, the selective COX-2 inhibitor, reduces the expression of COX-2 protein and promotes cell apoptosis induced by CSE in vascular endothelial cells. COX-2 may play an important role in protecting development of CSE-associated apoptosis of endothelial cells.


Assuntos
Apoptose/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase 2/farmacologia , Ciclo-Oxigenase 2/metabolismo , Pirazóis/farmacologia , Fumaça/efeitos adversos , Sulfonamidas/farmacologia , Celecoxib , Linhagem Celular , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Humanos , Nicotiana
12.
Nanotechnology ; 20(18): 185504, 2009 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-19420616

RESUMO

The interactions between four different graphenes (including pristine, B- or N-doped and defective graphenes) and small gas molecules (CO, NO, NO(2) and NH(3)) were investigated by using density functional computations to exploit their potential applications as gas sensors. The structural and electronic properties of the graphene-molecule adsorption adducts are strongly dependent on the graphene structure and the molecular adsorption configuration. All four gas molecules show much stronger adsorption on the doped or defective graphenes than that on the pristine graphene. The defective graphene shows the highest adsorption energy with CO, NO and NO(2) molecules, while the B-doped graphene gives the tightest binding with NH(3). Meanwhile, the strong interactions between the adsorbed molecules and the modified graphenes induce dramatic changes to graphene's electronic properties. The transport behavior of a gas sensor using B-doped graphene shows a sensitivity two orders of magnitude higher than that of pristine graphene. This work reveals that the sensitivity of graphene-based chemical gas sensors could be drastically improved by introducing the appropriate dopant or defect.


Assuntos
Gases/análise , Gases/química , Grafite/química , Modelos Químicos , Nanoestruturas/química , Nanotecnologia/métodos , Titânio/química , Absorção , Simulação por Computador , Substâncias Macromoleculares/química , Conformação Molecular , Nanoestruturas/ultraestrutura , Propriedades de Superfície
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