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1.
J Environ Manage ; 360: 121212, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38801803

RESUMO

This study investigates the impact of green finance (GF) and green innovation (GI) on corporate credit rating (CR) performance in Chinese A-share listed firms from 2018 to 2021. The least absolute shrinkage and selection operators (LASSOs) machine learning algorithms are first used to select the critical drivers of corporate credit performance. Then, we applied partialing-out LASSO linear regression (POLR) and double selection LASSO linear regression (DSLR) machine learning techniques to check the impact of GF and GI on CR. The main results reveal that a 1% increase in GF diminishes CR by 0.26%, whereas GI promotes CR performance by 0.15%. Moreover, the heterogeneity analysis reveals a more significant negative effect of GF on the CR performance of heavily polluting firms, non-state-owned enterprises, and firms in the Western region. The findings raise policies for managing green finance and encouraging green innovation formation, as well as addressing company heterogeneity to support sustainability.


Assuntos
Aprendizado de Máquina , Algoritmos , China
2.
J Chem Phys ; 160(7)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38364001

RESUMO

In this work, charge photogeneration and recombination processes of PM6:IDIC-4F and PM6:IDIC blend films were investigated by the steady-state and time-resolved spectroscopies, as well as the time-dependent density functional theory calculations. The peaks in absorption and photoluminescence (PL) spectra of IDIC and IDIC-4F solutions were assigned by combining the experiment and the simulation of UV-vis absorption and PL spectra. For neat acceptor films, the exciton diffusion length of neat IDIC and IDIC-4F films was estimated as ∼28.9 and ∼19.9 nm, respectively. For PM6-based blend films, we find that the fluorine substitution engineering on the IDIC acceptor material can increase the phase separate size of acceptor material in blend films, resulting in the reduction of dissociation efficiencies of acceptor excitons. In addition, we find that the charge recombination in PM6:IDIC-4F is dominated by bimolecular recombination, in comparison to geminate type carrier recombination in PM6:IDIC blend films. In addition, we find that thermal annealing treatment has a weak influence on carrier recombination but slightly reduces the exciton dissociation efficiency of acceptor in PM6:IDIC blend films, leading to a slightly reduced power conversion efficiency of PM6:IDIC solar cells. These results may shed light on the design of high-performance semiconductor molecules for application in solar cells.

4.
Cancer Imaging ; 23(1): 34, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37016465

RESUMO

BACKGROUND: The efficacy of 18F-fluorodeoxyglucose (18F-FDG) Positron Emission Tomography/Computed Tomography(PET/CT) in evaluating the neck status in clinically node-negative (cN0) oral squamous cell carcinoma(OSCC) patients was still unsatisfying. We tried to develop a prediction model for nodal metastasis in cN0 OSCC patients by using metabolic and pathological variables. METHODS: Consecutive cN0 OSCC patients with preoperative 18F-FDG PET/CT, subsequent surgical resection of primary tumor and neck dissection were included. Ninety-five patients who underwent PET/CT scanning in Shanghai ninth people's hospital were identified as training cohort, and another 46 patients who imaged in Shanghai Universal Medical Imaging Diagnostic Center were selected as validation cohort. Nodal-status-related variables in the training cohort were selected by multivariable regression after using the least absolute shrinkage and selection operator (LASSO). A nomogram was constructed with significant variables for the risk prediction of nodal metastasis. Finally, nomogram performance was determined by its discrimination, calibration, and clinical usefulness. RESULTS: Nodal maximum standardized uptake value(nodal SUVmax) and pathological T stage were selected as significant variables. A prediction model incorporating the two variables was used to plot a nomogram. The area under the curve was 0.871(Standard Error [SE], 0.035; 95% Confidence Interval [CI], 0.787-0.931) in the training cohort, and 0.809(SE, 0.069; 95% CI, 0.666-0.910) in the validation cohort, with good calibration demonstrated. CONCLUSIONS: A prediction model incorporates metabolic and pathological variables has good performance for predicting nodal metastasis in cN0 OSCC patients. However, further studies with large populations are needed to verify our findings.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18 , Neoplasias Bucais/diagnóstico por imagem , Neoplasias Bucais/cirurgia , Metástase Linfática , China , Estudos Retrospectivos , Compostos Radiofarmacêuticos
5.
Artigo em Inglês | MEDLINE | ID: mdl-36834301

RESUMO

Contamination of industry-derived antimony (Sb) is currently of great concern. This study was conducted to identify the source of Sb together with other potential toxic elements (PTEs) in a typical industrial area in China and emphasize the contribution of Sb to ecological risk in the local aquatic environment. By investigating the distribution of nine PTEs in surface water in Wujiang County in dry and wet seasons, this study revealed that textile wastewater was the main source of Sb. The distribution of Sb (0.48~21.4 µg/L) showed the least seasonal variation among the nine elements. Factor analysis revealed that the factor that controlled Sb distribution is unique. In general, Sb was more concentrated in the southeastern part of the study area where there was a large number of textile industries, and was affected by the specific conductivity and total dissolved solids in water (p < 0.01). Sb concentration in 35.71% of samples collected from the drainage outlet exceeded the standard limit of 10 µg/L. Results from three pollution assessment methods suggested that >5% of the sampling sites were slightly too heavily polluted and Sb contributed the most. Therefore, it is necessary to strengthen the administrative supervision of local textile enterprises and elevate the local standard of textile wastewater emission.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Lagos/análise , Indústria Têxtil , Águas Residuárias , Poluentes Químicos da Água/análise , Poluição da Água/análise , China , Água/análise , Medição de Risco , Metais Pesados/análise
6.
Front Bioeng Biotechnol ; 10: 1091752, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466322

RESUMO

[This corrects the article DOI: 10.3389/fbioe.2022.977282.].

7.
Front Bioeng Biotechnol ; 10: 977282, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36159673

RESUMO

With the continuous progress and development in biomedicine, metallic biomedical materials have attracted significant attention from researchers. Due to the low compatibility of traditional metal implant materials with the human body, it is urgent to develop new biomaterials with excellent mechanical properties and appropriate biocompatibility to solve the adverse reactions caused by long-term implantation. High entropy alloys (HEAs) are nearly equimolar alloys of five or more elements, with huge compositional design space and excellent mechanical properties. In contrast, biological high-entropy alloys (Bio-HEAs) are expected to be a new bio-alloy for biomedicine due to their excellent biocompatibility and tunable mechanical properties. This review summarizes the composition system of Bio-HEAs in recent years, introduces their biocompatibility and mechanical properties of human bone adaptation, and finally puts forward the following suggestions for the development direction of Bio-HEAs: to improve the theory and simulation studies of Bio-HEAs composition design, to quantify the influence of composition, process, post-treatment on the performance of Bio-HEAs, to focus on the loss of Bio-HEAs under actual service conditions, and it is hoped that the clinical application of the new medical alloy Bio-HEAs can be realized as soon as possible.

8.
Int J Nanomedicine ; 17: 953-967, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35280336

RESUMO

Purpose: In order to overcome the biological barriers at all levels and enhance the delivery efficiency of siRNA, we have prepared a multifunctional siRNA delivery system (CHCE/siRNA nanoparticles) through self-assembly of the carboxymethyl chitosan modified with histidine, cholesterol, and anti-EGFR antibody (CHCE). Methods: The morphology of CHCE/siRNA NPs was detected by dynamic light scattering and scanning electron microscope. In vitro, we assessed the tumor-targeting, cellular uptake, and endosomal escape by flow cytometry and confocal laser scanning microscopy, confirming the CHCE/siRNA NPs functions in gene silencing and cell killing ability. In vivo, we examined the biodistribution of the CHCE/siRNA NPs by the IVIS imaging system and confirmed the therapeutic effect of NPs in the nude-mouse tumor model. Results: The CHCE/siRNA NPs exhibited nanosized spherical with narrow size distribution. In vitro, the CHCE/siRNA NPs incorporated a dual capability of tumor targeting and pH response that could facilitate cellular bind, cellular uptake, and endosomal escape. The CHCE/siRNA NPs could effectively silence the vascular endothelial growth factor A (VEGFA) to cause cell apoptosis and inhibit proliferation. In vivo, the CHCE/siRNA NPs could target tumor sites to knock down VEGFA and achieve a better anti-tumor effect. Conclusion: We successfully prepared a novel siRNA delivery system with the double capability of tumor targeting and pH response, which can break through the biological barriers to penetrate deep into tumors and achieve better therapeutic tumor effects, providing a new ideal delivery platform for siRNA.


Assuntos
Nanopartículas , Fator A de Crescimento do Endotélio Vascular , Animais , Concentração de Íons de Hidrogênio , Camundongos , RNA Interferente Pequeno/genética , Distribuição Tecidual , Fator A de Crescimento do Endotélio Vascular/genética
9.
J Nanobiotechnology ; 20(1): 166, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35346194

RESUMO

The development of multidrug resistance (MDR) during cancer chemotherapy is a major challenge in current cancer treatment strategies. Numerous molecular mechanisms, including increased drug efflux, evasion of drug-induced apoptosis, and activation of DNA repair mechanisms, can drive chemotherapy resistance. Here we have identified the major vault protein (MVP) and the B-cell lymphoma-2 (BCL2) gene as two potential factors driving MDR in esophageal squamous cell carcinoma (ESCC). We have designed a novel and versatile self-assembling nanoparticle (NP) platform on a multifunctional carboxymethyl chitosan base to simultaneously deliver Adriamycin, and siRNAs targeting MVP and BCL2 (CEAMB NPs), thus reducing drug efflux and promoting apoptosis of esophageal cancer cells. To achieve effective delivery to tumor tissues and inhibit tumor growth in vivo, carboxymethyl chitosan was engineered to contain multiple histidines for enhanced cytosol delivery, cholesterol for improved self-assembly, and epidermal growth factor receptor (EGFR) antibodies to target cancer cells. Our results indicate that these nanoparticles are efficiently synthesized with the desired chemical composition to self-assemble into cargo-containing NPs. Furthermore, we have shown that the synthesized NPs will successfully inhibit cancer cells growth and tumor development when delivered to cultured ESCC cells or to in vivo mouse xenograft models. Our engineered NPs offer a potential novel platform in treating various types of chemotherapy-resistant tumors.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Nanopartículas Multifuncionais , Animais , Doxorrubicina/farmacologia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Neoplasias Esofágicas/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/genética , Humanos , Camundongos , RNA Interferente Pequeno
10.
Front Psychol ; 13: 808150, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35222196

RESUMO

Our research aimed to investigate the effectiveness of auditory, visual, and audiovisual warning signals for capturing the attention of the pilot, and how stimulus onset asynchronies (SOA) in audiovisual stimuli affect pilots perceiving the bimodal warning signals under different perceptual load conditions. In experiment 1 of the low perceptual load condition, participants discriminated the location (right vs. left) of visual targets preceded by five different types of warning signals. In experiment 2 of high perceptual load, participants completed the location task identical to a low load condition and a digit detection task in a rapid serial visual presentation (RSVP) stream. The main effect of warning signals in two experiments showed that visual and auditory cues presented simultaneously (AV) could effectively and efficiently arouse the attention of the pilots in high and low load conditions. Specifically, auditory (A), AV, and visual preceding auditory stimulus by 100 ms (VA100) increased the spatial orientation to a valid position in low load conditions. With the increase in visual perceptual load, auditory preceding the visual stimulus by 100 ms (AV100) and A warning signals had stronger spatial orientation. The results are expected to theoretically support the optimization design of the cockpit display interface, contributing to immediate flight crew awareness.

11.
IEEE Trans Pattern Anal Mach Intell ; 44(3): 1591-1603, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32986542

RESUMO

Real-time semantic video segmentation is a challenging task due to the strict requirements of inference speed. Recent approaches mainly devote great efforts to reducing the model size for high efficiency. In this paper, we rethink this problem from a different viewpoint: using knowledge contained in compressed videos. We propose a simple and effective framework, dubbed TapLab, to tap into resources from the compressed domain. Specifically, we design a fast feature warping module using motion vectors for acceleration. To reduce the noise introduced by motion vectors, we design a residual-guided correction module and a residual-guided frame selection module using residuals. TapLab significantly reduces redundant computations of the state-of-the-art fast semantic image segmentation models, running 3 to 10 times faster with controllable accuracy degradation. The experimental results show that TapLab achieves 70.6 percent mIoU on the Cityscapes dataset at 99.8 FPS with a single GPU card for the 1024×2048 videos. A high-speed version even reaches the speed of 160+ FPS. Code will be available soon at https://github.com/Sixkplus/TapLab.

12.
IEEE Trans Med Imaging ; 38(8): 1971-1980, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30998461

RESUMO

The segmentation of pancreas is important for medical image analysis, yet it faces great challenges of class imbalance, background distractions, and non-rigid geometrical features. To address these difficulties, we introduce a deep Q network (DQN) driven approach with deformable U-Net to accurately segment the pancreas by explicitly interacting with contextual information and extract anisotropic features from pancreas. The DQN-based model learns a context-adaptive localization policy to produce a visually tightened and precise localization bounding box of the pancreas. Furthermore, deformable U-Net captures geometry-aware information of pancreas by learning geometrically deformable filters for feature extraction. The experiments on NIH dataset validate the effectiveness of the proposed framework in pancreas segmentation.


Assuntos
Aprendizado Profundo , Processamento de Imagem Assistida por Computador/métodos , Pâncreas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Bases de Dados Factuais , Humanos
13.
PLoS One ; 11(9): e0162570, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27606422

RESUMO

Dermatosis often as a chronic disease requires effective long-term treatment; a comprehensive evaluation of mental health of dermatology drug does not receive enough attention. An interaction between dermatology and psychiatry has been increasingly described. Substantial evidence has accumulated that psychological stress can be associated with pigmentation, endocrine and immune systems in skin to create the optimal responses against pathogens and other physicochemical stressors to maintain or restore internal homeostasis. Additionally, given the common ectodermal origin shared by the brain and skin, we are interested in assessing how disruption of skin systems (pigmentary, endocrine and immune systems) may play a key role in brain functions. Thus, we selected three drugs (hydroquinone, isotretinoin, tacrolimus) with percutaneous excessive delivery to respectively intervene in these systems and then evaluate the potential neurotoxic effects. Firstly, C57BL/6 mice were administrated a dermal dose of hydroquinone cream, isotretinoin gel or tacrolimus ointment (2%, 0.05%, 0.1%, respectively, 5 times of the clinical dose). Behavioral testing was performed and levels of proteins were measured in the hippocampus. It was found that mice treated with isotretinoin or tacrolimus, presented a lower activity in open-field test and obvious depressive-like behavior in tail suspension test. Besides, they damaged cytoarchitecture, reduced the level of 5-HT-5-HT1A/1B system and increased the expression of apoptosis-related proteins in the hippocampus. To enable sensitive monitoring the dose-response characteristics of the consecutive neurobehavioral disorders, mice received gradient concentrations of hydroquinone (2%, 4%, 6%). Subsequently, hydroquinone induced behavioral disorders and hippocampal dysfunction in a dose-dependent response. When doses were high as 6% which was 3 times higher than 2% dose, then 100% of mice exhibited depressive-like behavior. Certainly, 6% hydroquinone exposure elicited the most serious impairment of hippocampal structure and survival. The fact that higher doses of hydroquinone are associated with a greater risk of depression is further indication that hydroquinone is responsible for the development of depression. These above data demonstrated that chronic administration of different dermatology drugs contributed into common mental distress. This surprising discovery of chemical stressors stimulating the hippocampal dysfunction, paves the way for exciting areas of study on the cross-talk between the skin and the brain, as well as is suggesting how to develop effective and safe usage of dermatological drugs in daily practice.


Assuntos
Comportamento Animal , Sistemas de Liberação de Medicamentos , Neuroquímica , Síndromes Neurotóxicas/etiologia , Administração Tópica , Animais , Apoptose/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Hipocampo/patologia , Hidroquinonas/administração & dosagem , Hidroquinonas/toxicidade , Isotretinoína/administração & dosagem , Isotretinoína/toxicidade , Masculino , Camundongos Endogâmicos C57BL , Modelos Biológicos , Receptor 5-HT1A de Serotonina/metabolismo , Receptor 5-HT1B de Serotonina/metabolismo , Serotonina/metabolismo , Tacrolimo/administração & dosagem , Tacrolimo/farmacologia
14.
Cytokine ; 74(1): 137-44, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25982845

RESUMO

Skin is the largest organ in human body and works as biologically active barrier to provide critical preservation of body homeostasis. The skin is highly innervated by a plenitude of nerve fiber subpopulations, each carrying one or more neuronal mediators. Melanocyte itself also intimately contact with nerve fibers to form 'synaptic-like structure' and its functions may be directly regulated by the mediators contained in terminals of intra-epidermal nerve fibers. Clinical and biochemical studies have suggested that calcitonin gene-related peptide (CGRP) is involved in vitiligo skin. The present study was designed to investigate the effect of CGRP on epidermal melanocytes. After treatment with CGRP ranging from 0 to 500 ng/mL for 48 h, tyrosinase activity and melanogenesis were with little changes compared to treatment with medium only in B16F10 cells. Treatment with 500 ng/mL of CGRP cooperates with substance P (SP) (0.1-10 nM) to decrease tyrosinase activity and decrease melanin biosynthesis in B16F10 cells in a concentration-dependent manner. Furthermore, CGRP (8-37) antagonizes the synergistic effect of CGRP. The effect of CGRP on the cell apoptosis was examined. Treatments with 0-500 ng/mL of CGRP for 24 h, the expression levels of cleaved caspase-3, total caspase-3, cleaved caspase-9 and total caspase-9 were increased in a concentration-dependent manner. And 500 ng/mL of CGRP induced B16F10 cell apoptosis showed by TUNEL assay. In addition, Bax expression was up-regulated and Bcl-2 down-regulated in response to CGRP treatment. Hence, the Bax/Bcl-2 ratio was significantly increased. These in vitro observations indicate the pro-apoptotic impact of CGRP on B16F10 cell.


Assuntos
Apoptose/efeitos dos fármacos , Peptídeo Relacionado com Gene de Calcitonina/farmacologia , Melaninas/antagonistas & inibidores , Melanócitos/efeitos dos fármacos , Melanócitos/fisiologia , Animais , Caspases/classificação , Caspases/genética , Linhagem Celular Tumoral , Células Epidérmicas , Epiderme/metabolismo , Melaninas/biossíntese , Camundongos , Monofenol Mono-Oxigenase , Substância P , Regulação para Cima , Proteína X Associada a bcl-2/genética
15.
Cytokine ; 69(1): 29-38, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25022959

RESUMO

Interleukin-18 (IL-18), a member of the IL-1 family of cytokines, was initially identified as an interferon (IFN)-γ-inducing factor. IL-18 is expressed in both immune and non-immune cells and participates in the adjustment of multitude cellular functions. Nonetheless, the effects of IL-18 on cortical neurons have not been explored. The present study was conducted to investigate the influence of IL-18 on rat primary cortical neurons and elucidate the underlying mechanisms. We proved that rrIL-18 increased the brain-derived neurotrophic factor (BDNF) expression in a time-dependent manner. Treatment with rrIL-18 (50 ng/ml) deactivated phosphatase and tensin homolog deleted on chromosome 10 (PTEN) by facilitating its phosphorylation, enhanced the expression of Phosphoinositide 3-OH kinase (PI3K) and p-Akt, standing for the activation of the PI3K/Akt pathway. As its pivotal downstream pathways, nuclear factor-kappa B (NF-κB), cAMP-responsive element binding protein (CREB)/Bcl-2 and glycogen synthase kinase-3ß (GSK-3ß) were examined in further steps. Our data revealed that rrIL-18 stimulated NF-κB activation, improved p-CREB and anti-apoptotic Bcl-2 expression levels. But rrIL-18 had little or no effect on GSK-3ß pathway. Besides, rrIL-18 increased levels of BDNF and Bcl-2/Bax ratio and decreased cleaved caspase-3 expression to protect cortical neurons from damage induced by oxygen-glucose deprivation (OGD). These results in vitro showed the protection of IL-18 on cortical neurons. And this direct neuroprotective effect of IL-18 is crippled by PI3K inhibitor wortmannin.


Assuntos
Córtex Cerebral/metabolismo , Interleucina-18/farmacologia , Fármacos Neuroprotetores/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Androstadienos/farmacologia , Animais , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Caspase 3/biossíntese , Córtex Cerebral/citologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Ativação Enzimática/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/biossíntese , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Interleucina-18/metabolismo , NF-kappa B/metabolismo , Neurônios/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/biossíntese , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Ratos , Wortmanina
16.
J Ethnopharmacol ; 143(1): 100-8, 2012 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-22750433

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Salvia Miltiorrhiza Bunge (also known as herb Danshen in Chinese) is a widely used Chinese herbal medicine. Tanshinone IIA (TSN IIA) is considered to be the most important bioactive ingredient in Danshen and exhibits an anti-atherosclerotic activity. AIM OF STUDY: To evaluate the protective effect of TSN IIA on the human endothelial EA.hy926 cells injured by hydrogen peroxide in vitro and its possible mechanism. MATERIALS AND METHODS: The EA.hy926 cells were incubated for 24h with different concentrations of TSN IIA (5, 10 and 20 µg/µL ) or DMEM. Subsequently, cells were treated with 300 µmol/L H(2)O(2) for another 4h. Then, the percentage of cell viability was evaluated by 3-(4, 5-di-methylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay. The apoptosis of EA.hy926 cells was detected by flow cytometry with AnnexinV-FITC/PI double staining and laser scanning spectral confocal technique. The generation of intracellular reactive oxygen species (ROS) generation was analyzed by flow cytometry. The mRNA expressions of caspase-3, Bcl-2 and Bax were tested by real time-reverse transcription polymerase chain reaction (real time RT-PCR). The protein expression of Bcl-2 and Bax was determined by Western blotting. MDA levels, NO production, LDH leakage, and SOD as well as caspase-3 activities were also measured using standard methods. RESULTS: Loss of cell viability and excessive cell apoptosis were observed in EA.hy926 cells after 4h of challenge with H(2)O(2) (300 µmol/L). However, cell apoptosis was attenuated in different concentrations of TSN IIA (5, 10 and 20 µg/µL) pretreated cells. Furthermore, TSN IIA markedly inhibited the elevation of ROS evoked by H(2)O(2). Real time RT-PCR and Western blotting analysis showed that TSN IIA significantly decreased the expressions of pro-apoptotic proteins (Bax and caspase-3) while significantly increased the expression of anti-apoptotic protein Bcl-2, and resulted in obvious reduction of Bax/Bcl-2 ratio in EA.hy926 cells induced by H(2)O(2). CONCLUSION: These observations provide preliminary evidence that TSN IIA protects EA.hy926 cells against H(2)O(2) damage, which is mainly associated with the ROS generation, followed by the imbalance of the Bax/Bcl-2 ratio, and caspase-3 activation leading to apoptosis.


Assuntos
Abietanos/farmacologia , Apoptose/efeitos dos fármacos , Aterosclerose/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Células Endoteliais/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fenantrolinas/farmacologia , Salvia miltiorrhiza/química , Abietanos/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Aterosclerose/prevenção & controle , Caspase 3/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Medicamentos de Ervas Chinesas/uso terapêutico , Células Endoteliais/metabolismo , Humanos , Peróxido de Hidrogênio , Fenantrolinas/uso terapêutico , Fitoterapia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína X Associada a bcl-2/metabolismo
17.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 27(7): 733-5, 2011 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-21722522

RESUMO

AIM: To observe the influence of tanshinone II A on the expression of toll like receptor 4(TLR4) and tumor necrosis factor-α(TNF-α) in cultured human umbilical veins endothelial cells EA.hy926 induced by LPS, and to investigate the molecular mechanism of tanshinone II A against atherosclerosis(AS). METHODS: The EA.hy926 cells were cultured in vitro. The mRNA and protein expression of TLR4 were tested by RT-PCR and immunocytochemistry technique respectively. The mRNA and protein expression of TNF-α were detected by RT-PCR and ELISA technique respectively. RESULTS: The expression of TLR4 and TNF-α were both increased compared to normal group after stimulation of LPS(P<0.05). The expression of TLR4 and TNF-α in tanshinone II A group were obviously inhibited compared to stimulation group(P<0.05). CONCLUSION: The molecular mechanism of tanshinone II A against AS is probably to inhibit the expression of TLR4 and TNF-α.


Assuntos
Abietanos/farmacologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Lipopolissacarídeos/farmacologia , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/genética , Abietanos/uso terapêutico , Aterosclerose/tratamento farmacológico , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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