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It is important to study the impact of land use change on terrestrial ecosystem carbon stocks in urban agglomerations for the optimization of land use structure and sustainable development in urban agglomerations. Based on the patch-generating land use simulation (PLUS) model and integrated valuation of ecosystem services and trade-offs (InVEST) model, a simulation was developed that predicted the land use change and carbon stock of the Guanzhong Plain urban agglomeration in 2040 under different scenarios and further analyzed the impact of land use change on carbon stock. The results showed that:â The land use types of the Guanzhong Plain urban agglomeration were mainly cultivated land, forest land, and grassland, which accounted for more than 90 % of the total study area. â¡ From 2000 to 2020, the carbon stock in the Guanzhong Plain showed a continuous downward trend, with cropland, woodland, and grassland being the main sources of carbon stock in the Guanzhong Plain, and the overall carbon stock declined by 15.12×106 t, with the spatial distribution presenting the distribution characteristics of "high in the north and south and low in the middle." ⢠By 2040, the carbon stock would decrease the most under the urban development scenario, with a total reduction of 27.08×106 t, and the least under the ecological development scenario, with a total reduction of 4.14×106t. The research results can provide data support for the high-quality development and rational land use planning of the Guanzhong Plain urban agglomeration.
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To quantitatively evaluate the effects of drought on vegetation productivity in the Qinling-Daba Mountains, we analyzed the temporal and spatial characteristics of gross primary productivity (GPP) and drought, identified the fluctuation of negative GPP extremes under different vegetation types, and quantified the drought vulnerability and drought risk of GPP from 2001 to 2020 with MODIS GPP products and standardized precipitation evapotranspiration index (SPEI). The results showed that the annual GPP from 2001 to 2020 had an increasing trend in 98.0% of areas in the Qinling-Daba Mountains. The GPP of all vegetation types except wetlands increased significantly. SPEI decreased in 23.8% of area in the Qinling-Daba Mountains from 2001 to 2020. The number of negative GPP extremes had no significant trend, but abnormal GPP fluctuations had intensified, especially in the cultivated land. After 2011, the proportion of concurrent negative GPP extreme and drought had decreased for all vegetation types, but the spatial and temporal range of drought in these negative GPP extremes showed an expanding trend. Compared with the pattern during 2001-2010, the proportion of area with positive drought vulnerability and drought risk increased by 104.1% and 6.7% after 2011, indicating that the area with drought-induced GPP decline had expanded. Among all the vegetation types, drought caused the largest decrease of GPP in wetlands. The results revealed that drought led to an aggravation of GPP fluctuations and increased frequency of GPP extremes in the Qinling-Daba Mountains from 2001 to 2020, which resulted in GPP decline with different magnitudes in most vegetation types.
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Secas , Ecossistema , China , Mudança ClimáticaRESUMO
The ecosystem services cascade (ESC), which connects the components of ecosystem services with social value and builds a bridge between natural science and social science, can help decision-makers better integrate the concept of ecosystem services into decision-making. We reviewed the concept and the research progress of ESC. From the perspective of theory, the theoretical research of ESC mainly focused on how to accurately define each component and the causal relationship among different components, improve the practicability and applicability of ESC model, and how to effectively connect stakeholders and ecosystem service structure. From the perspective of application, ESC played an important role in ecosystem services mapping, ecosystem services assessment, and policy making. There were still great uncertainties in index selection and mutual feedback mechanism. Future research should be strengthened from the following aspects: to pay more attention to the structure process and classification standard of ecosystem services, to make up the lack of ESC of the feedback mechanism through multi-model fusion and regional survey, and to provide scientific guidance for human-earth coupling and sustainable development combined with regional characteristics .
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Conservação dos Recursos Naturais , Ecossistema , Tomada de Decisões , Ecologia , Humanos , Formulação de PolíticasRESUMO
A mild and efficient method has been developed using ultrasound irradiation for oxidative cleavage of hydrobenzoin with ACC/silica gel in dichloromethane. A high yield of 72-99% has been obtained for the oxidation of a series of hydrobenzoins into aromatic aldehydes at room temperature.
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Synthesis of 2,3-epoxyl-1,3-diaryl-1-propanone via epoxidation of chalcone with aqueous sodium hypochlorite was carried out in 62-92% yields using benzyldimethyltetradecyl ammonium chloride as phase transfer catalyst under ultrasound irradiation. Compared to the classical method, the advantages of this method are a safer oxidant, mild conditions, no toxic solvent and shorter reaction time.
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Chalconas/síntese química , Compostos de Epóxi/síntese química , Catálise , Cromatografia em Camada Fina , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Oxidantes , Hipoclorito de Sódio , UltrassomRESUMO
MicroRNAs (miRNAs) play important roles in the development of head and neck squamous cell carcinoma (HNSCC). However, their potential clinical value as biomarkers remains poorly known. The aim of this study was to assess the association between tissue/serum miR-31 expression levels and prognosis of HNSCC. In this clinical study, tumor samples were obtained from 118 patients with HNSCC and 48 patients with oral epithelial dysplasia, and blood samples were collected from all the HNSCC cases and 60 normal controls. The expression levels of tissue/serum miR-31 were measured by real-time PCR. Chi-square test was used to evaluate the correlation between tissue/serum miR-31 and clinical parameters of HNSCC. Survival curves were constructed using the Kaplan-Meier method and log-rank test. Multivariate Cox regression analyses were used to estimate independent predictors of survival for HNSCC. Our findings showed that tissue miR-31 levels in HNSCC tumor specimens exhibited higher than that in oral epithelial dysplasia samples and normal tissues. Oral epithelial dysplasia with higher expression of miR-31 was more prone to progress into HNSCC. Likewise, serum miR-31 expression in HNSCC patients was markedly increased in compared to normal controls. Moreover, serum miR-31 performed well to distinguish HNSCC subjects from controls. In addition, increased tissue/serum miR-31 expression was positively correlated with poor clinical variables and dismal prognosis. Finally, tissue miR-31 was confirmed to be an independent prognostic factor for HNSCC. Taken together, miR-31 had strong potential as a promising biomarker in HNSCC detection.
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Modern radiotherapy (RT) is being enriched by big digital data and intensive technology. Multimodality image registration, intelligence-guided planning, real-time tracking, image-guided RT (IGRT), and automatic follow-up surveys are the products of the digital era. Enormous digital data are created in the process of treatment, including benefits and risks. Generally, decision making in RT tries to balance these two aspects, which is based on the archival and retrieving of data from various platforms. However, modern risk-based analysis shows that many errors that occur in radiation oncology are due to failures in workflow. These errors can lead to imbalance between benefits and risks. In addition, the exact mechanism and dose-response relationship for radiation-induced malignancy are not well understood. The cancer risk in modern RT workflow continues to be a problem. Therefore, in this review, we develop risk assessments based on our current knowledge of IGRT and provide strategies for cancer risk reduction. Artificial intelligence (AI) such as machine learning is also discussed because big data are transforming RT via AI.
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OBJECTIVE: Tumor dormancy has been defined clinically as a condition in which tumor cells are present but do not grow for a long period of time. Breast cancer is noted for its long periods of tumor dormancy and metastases can occur many years after treatment. METHOD: Simulating the characteristics of breast cancer patients after treatment, we established the animal model of breast cancer dormancy by inoculating 500 Ca761-03 cells into the limb muscle of 615 mice and then selecting animals with tumor dormancy 2 months post inoculation (corresponding to 5 years for humans). RESULTS: Two months after inoculation of Ca761-03 cells into the muscle of 615 mice, tumor occurred in 30% of the mice. The remaining 70% of mice did not show tumor growth. After repeated traumatic stimulation, 90% of the mice developed tumors after 5 months, therefore representing tumor dormancy. CONCLUSIONS: These results demonstrate that breast cancer cells can remain in a dormant state for long periods of time in vivo. Trauma can stimulate the dormant tumor cells to proliferate again, and causes tumor relapse. This murine model system promises a sound animal model for the study of solid tumor dormancy.
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Neoplasias da Mama/fisiopatologia , Modelos Animais de Doenças , Neoplasias do Colo do Útero/fisiopatologia , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Progressão da Doença , Feminino , Humanos , Masculino , Camundongos , Recidiva Local de Neoplasia , Transplante de Neoplasias , Distribuição Aleatória , Neoplasias do Colo do Útero/patologiaRESUMO
Forty-nine patients with stage IIb cervical cancer were included to investigate the changes in bladder volume in response to different approaches to maintaining consistent bladder filling. The impacts of age (P age), water consumption (P wat ), and body mass index (BMI, P bmi ) on the mean urinary inflow rate (v tot ) were analysed. The bladder volume (BV) increased linearly over time. A large variation in v tot among individuals was observed, ranging from 0.19 to 5.13 ml/min. The v tot was correlated with P age (R = -0.53, p = 0.01) and P wat (R = 0.84, p = 0.00), and no correlation between v tot and P bmi was found (p > 0.05). Therefore, v tot could be parameterized using two methods: multivariable linear regression and iterative fitting. There was no statistically significant difference between the two methods. The model accuracy was successfully assessed with several validation tests for patients with good compliance (79.2% of all patients), and the proportion of radiotherapy (RT) fractions with zero wait time (one ultrasound (US) scan) increased from 6.5% to 41.2%. The optimal US scanning number and RT time could be provided using this model. This adaptive RT approach could reduce patient discomfort caused by holding onto urine and reduce technician labour as well as cost.
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Bexiga Urinária/anatomia & histologia , Bexiga Urinária/fisiologia , Neoplasias do Colo do Útero/radioterapia , Adulto , Idoso , Feminino , Humanos , Individualidade , Pessoa de Meia-Idade , Modelos EstatísticosRESUMO
PURPOSE: To explore the effect of different doses of radiation on human salivary gland adenoid cystic carcinoma cells (SACC-83, SACC-LM). METHODS: Different doses of radiation (0, 2, 4, 6, 8, 10 Gy) were applied to SACC-83, SACC-LM cells and the cells were continued to culture for 48 h. CCK-8 test, flow cytometry(FCM) and cell scratch experiment were used to observe cell proliferation, apoptosis and cell migration. SPSS19.0 software package was used for data analysis. RESULTS: The effect of radiation on SACC-LM cells survival rate, cell apoptosis, heteroploid and cell migration ability were significantly greater than that on SACC-83 cells (P<0.05). In SACC-83 cells, compared with other doses of radiation, 6 Gy of irradiation was the most sensitive on cell survival rate, cell apoptosis, heteroploid and cell migration ability. CONCLUSIONS: Radiation sensitivity of SACC-LM was greater than that of SACC-83 cells. With 6 Gy of radiation, changes of biology in SACC-83 cells most significant than other doses of radiation.
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Apoptose , Carcinoma Adenoide Cístico/radioterapia , Neoplasias das Glândulas Salivares/radioterapia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Humanos , Glândulas SalivaresRESUMO
OBJECTIVE: To establish a rabbit tumor cell line and to characterize its biological parameters. METHODS: VX2 tumor tissue was used for the primary culture in vitro. After 40 passages, the cell morphology, CK expression (immunohistochemical staining), cell cycle, karyotype and tumorigenecity in rabbits and nude mice were investigated. RESULTS: The newly established cell line VX2 was maintained in continuous culture for over 70 passages in 10 months. Morphologically, VX2 cells were polygonal to short spindled. Tonal fibril and tight junction were found under the electron microscope. CK was positive. The cell cycle analysis showed 69.3% in G1 phase, 5.6% in G2 phase and 25.1% in S phase. The population doubling time was 34.5 hours. The chromosomal analysis showed a hypotriploidy with a median chromosome number of 58 approximately 62. The tumorigenecity in rabbits and nude mice were both 100%. CONCLUSION: The established VX2 cell line derived from rabbit squamous carcinoma could serve as a model system for experimental oncology in the rabbit.
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Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Animais , Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/ultraestrutura , Ciclo Celular , Queratinas/análise , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Poliploidia , CoelhosRESUMO
BACKGROUND: The objective of this study is to detect HMGA2 expression in renal carcinoma to explore its relationship with clinicopathology and its significance in prognosis. METHODS: Expressions of HMGA2 mRNA and protein were detected in 50 renal carcinoma specimens, 50 corresponding adjacent normal kidney tissue samples and 40 renal benign tumour specimens via reverse transcription polymerase chain reaction and immunohistochemical assay. Expression analysis was performed along with clinical data analysis. RESULTS: The relative expression levels of HMGA2 mRNA in renal carcinoma, renal benign tumour tissues and adjacent normal renal tissues were 0.84±0.23, 0.19±0.06 and 0.08±0.04, respectively. HMGA2 protein positive rates were 68.0%, 7.5% and 2.0%, with a significant difference (P<0.05). HMGA2 expression was not significantly correlated with gender, age, tumour size and histological type (P>0.05), but was significantly correlated with TNM stages and lymph node metastasis (P<0.05). CONCLUSIONS: The expressions of HMGA2 gene and protein in renal carcinoma were closely correlated with tumour formation, progression and metastasis. HMGA2 may become a powerful new pathological marker and prognostic factor for renal carcinoma.
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OBJECTIVE: To analyze the expressions of Bcl-2, B7-H1, EGFR and VEGF in colorectal cancer for the further investigation of their correlations with the clinical pathological features of colorectal cancer. METHOD: Fresh colorectal cancer tissues and the expressions of Bcl-2, B7-H1, VEGF and EGFR in paraneoplastic normal mucosal tissues of 57 cases were tested by immunohistochemisty method, and the results were analyzed by SPSS10.0. RESULTS: 1. Compared with paraneoplastic normal tissues, the expressions of Bcl-2 and B7-H1 in colorectal cancer tissues increased significantly with significant difference (P<0.05), while the expression of EGFR and VEGF in colorectal cancer tissues showed no significant difference with those in paraneoplastic normal tissue (P>0.05); 2. The correlation with clinical pathological features: there was significant difference of expression rates of EGFR between different genders (P<0.05); the expressions of BCL-2 and B7-H1 in colorectal cancer of the high- and medium- differentiated groups were significantly higher than those of the low-differentiated group, and the difference was significant (P<0.01); compared with the colorectal cancer patients without lymph node metastasis (Dukes stage A+B), the expression of B7-H1 in patients with lymph node metastasis (Dukes stage C+D) was significantly higher (P<0.05); 3. Within the high- and medium- differentiated colorectal cancer tissues, Bcl-2 expression rate in B7-H1 negative group was higher than the positive group with significant difference (P<0.01). CONCLUSIONS: In colorectal carcinoma, Bcl-2, B7-H1, EGFR and VEGF were all expressed, independent from age and depth of invasion. However, the expression level of Bcl-2 and B7-H1 correlated with tissue differentiation, and the latter also had correlation with tumor staging. Meanwhile, the short-term follow-up showed that high expression of Bcl-2/B7-H1 existed in death cases. Therefore, the expression detection of Bcl-2, B7-H1 might provide a clear understanding of the biological behavior of colorectal cancer, and was important for the diagnosis, treatment and prognosis judgment of colorectal cancer.
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OBJECTIVE: To investigate the clinical effect of Tianzhi Granule (TZK) on senile vascular dementia (VaD), which is classified as sthenia of liver-yang. METHOD: Two hundred VaD patients were treated with TZK (0.5 g/bag), which was taken one bag each, three times a day. The treatment course was one month and they were treated for rwo courses. RESULT: TZK could remarkably increase gnosia and activity, with no striking difference from that of positive control group (P > 0.05). Simultaneously, TZK could significantly improve the clinical syndrome of traditional Chinese medicine and viability. It could also drastically reduce the whole blood and plasma viscosity and improve erythrodegeneration and abnormality of aggregation index in the abnormal blood viscosity patients. CONCLUSION: TMC has certain effects on senile VaD.
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Demência Vascular/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Fitoterapia , Plantas Medicinais , Idoso , Viscosidade Sanguínea/efeitos dos fármacos , Demência Vascular/sangue , Método Duplo-Cego , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/isolamento & purificação , Agregação Eritrocítica/efeitos dos fármacos , Deformação Eritrocítica/efeitos dos fármacos , Humanos , Medicina Tradicional Chinesa , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Plantas Medicinais/química , Reconhecimento Psicológico/efeitos dos fármacosRESUMO
This study aims to investigate the suitability of volumetric-modulated arc therapy (VMAT) with RapidArc for primary leiomyosarcoma (LMS) in the spine, and present a new method to improve the target coverage and organs at risk (OAR) sparing. Five patients with LMS were retrospectively reviewed. The intensity-modulated radiotherapy (IMRT) with five coplanar beams (5b-IMRT) or seven coplanar beams (7b-IMRT), and VMAT using four quasi-quarter coplanar arcs (4q-VMAT) or two full coplanar arcs (2f-VMAT) were generated. Planning target volume (PTV) dose coverage, OAR dose sparing, conformity index (CI), and homogeneity index (HI) were evaluated. A hollow-cylinder model (HCM) was also used for feasible optimal beam arrangements. The mean doses to PTV were 95.2% ± 1.0%, 93.0% ± 1.0%, 97.9% ± 1.0% and 96.2% ± 1.5% for 4q-VMAT, 2f-VMAT, 5b-IMRT and 7b-IMRT respectively, while the mean maximum doses to spinal cord (SC) were 43.7 ± 0.9 Gy, 42.0 ± 0.8 Gy, 41.4 ± 1.2 Gy and 40.6 ± 1.4 Gy. Compared to 5b-IMRT, the mean doses delivered to kidneys decreased by about 35.1% (8.5 Gy), 2.5% (0.6 Gy) and 35.5% (8.6 Gy) for 4q-VMAT, 2f-VMAT, and 7b-IMRT, respectively. The CI proposed by Baltas et al. was twice as good with IMRT than with 4q-VMAT, and the numbers of monitor units were increased five- and threefold with 7b-IMRT and with 5b-IMRT compared to VMAT. The unexpected results we presented here show that VMAT technique can't achieve highly conformal treatment plans while maintaining SC sparing for LMS in the spine. An approach is proposed based on a hollow-cylinder model, but it is difficult to apply to clinical practice. In this case, VMAT is not superior to IMRT except for significant reduction in delivery time.
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Leiomiossarcoma/radioterapia , Radioterapia de Intensidade Modulada , Neoplasias da Medula Espinal/radioterapia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão , Órgãos em Risco , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos , Coluna Vertebral/patologia , Resultado do TratamentoRESUMO
By using Penman-Monteith model and Hurst index model, this paper analyzed the spatiotemporal variation patterns of potential evapotranspiration (ET0) in the five provinces of Northwest China in 1960-2011. In the meantime, the dominant factors driving the variations of the ET0 were quantitatively analyzed by using sensitivity analysis method. In 1960-2011, the ET0 in the five provinces presented an overall decreasing trend, with a drop rate of -0.72 mm x a(-1), but the ET0 increased gradually after 1993. An obvious spatial difference was shown in the annual average ET0. The average ET0 in the five provinces was 1158 mm (675-2282 mm), wit the maximum (2282 mm) in Qijiaojing of Xinjiang and the low values (>800 mm) in Qinba Mountains in south Shaanxi. Except in spring, the ET0 in other seasons showed a decreasing trend. In the analysis of future trend, the ET0 in most areas (81.4%) of Northwest China would present a trend from decrease to increase. Therefore, under the background of global warming, the warm and wet degree in Northwest China would be somewhat weakened, but the ET0 in the middle part of Xinjiang would be decreased continuously. Wind speed was the main factor affecting the ET0 in Northwest China at both annual and monthly scales, but the affecting extent of wind speed differed with seasons and areas. The spatial extent affected by the wind speed in winter expanded across the entire five provinces of Northwest China, while the spatial extent affected by the wind speed in summer included the entire Xinjiang and the northwest of Gansu and Qinghai.
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Produtos Agrícolas/crescimento & desenvolvimento , Ecossistema , Modelos Teóricos , Transpiração Vegetal , Movimentos da Água , China , Mudança Climática , Análise Espaço-Temporal , Temperatura , Água/metabolismoRESUMO
OBJECTIVE: To assess the prevalence of and related risk factors for aspirin resistance in elderly patients with coronary artery disease (CAD). METHODS: Two hundred and forty-six elderly patients (75.9 ± 7.4 years) with CAD who received daily aspirin therapy (≥ 75 mg) over one month were recruited. The effect of aspirin was assessed using light transmission aggregometry (LTA) and thrombelastography platelet mapping assay (TEG). Aspirin resistance was defined as ≥ 20% arachidonic acid (AA)-induced aggregation and ≥ 70% adenosine diphosphate (ADP)-induced aggregation in the LTA assay. An aspirin semi-responder was defined as meeting one (but not both) of the criteria described above. Based on the results of TEG, aspirin resistance was defined as ≥ 50% aggregation induced by AA. RESULTS: As determined by LTA, 23 (9.3%) of the elderly CAD patients were resistant to aspirin therapy; 91 (37.0%) were semi-responders. As determined by TEG, 61 patients (24.8%) were aspirin resistant. Of the 61 patients who were aspirin resistant by TEG, 19 were aspirin resistant according to LTA results. Twenty-four of 91 semi-responders by LTA were aspirin resistant by TEG. Multivariate logistic regression analysis revealed that elevated fasting serum glucose level (Odds ratio: 1.517; 95% CI: 1.176-1.957; P = 0.001) was a significant risk factor for aspirin resistance as determined by TEG. CONCLUSIONS: A significant number of elderly patients with CAD are resistant to aspirin therapy. Fasting blood glucose level is closely associated with aspirin resistance in elderly CAD patients.
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This study was purposed to investigate the effect of clopidogrel on gene expression profile of cultured human umbilical vein endothelial cell (HUVEC) line (EA.hy926), and explore its potential molecule mechanism. A Affymetrix U133 plus 2.0 oligonucleotide microarray was applied to detect the alteration of gene expression profile induced by clopidogrel in HUVEC. Real time RT-PCR was used to verify the result of selected differentially expressing genes. The results showed that total 508 genes (including 139 up-regulated and 369 down-regulated genes) were obtained with differential expression more than 1.5-fold after clopidogrel (10 µmol/L) acted on HUVEC for 48 h. Clopidogrel affected the expression levels of genes involved protein binding, transcription factor activity, zinc ion binding, regulation of DNA-dependent transcription, transcription, RNA splicing and so on. It is concluded that the clopidogrel modulate function of endothelial cells by regulating sets of genes through different pathway.
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Células Endoteliais da Veia Umbilical Humana/metabolismo , Ticlopidina/análogos & derivados , Transcriptoma , Linhagem Celular , Clopidogrel , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , Ticlopidina/farmacologia , Transcrição GênicaRESUMO
Krüppel-like transcription factors (KLFs) play a key role in both vascular development and pathophysiological processes, but little is known about the relationship between KLFs and oxidized low-density lipoprotein (ox-LDL). We investigated the effects of ox-LDL on KLF expression. Furthermore, since atorvastatin is commonly used to treat high cholesterol, we also examined the role of this drug in the regulation of KLF expression. The human umbilical vein endothelial cell line EA.hy926 was treated with atorvastatin and ox-LDL alone or in combination, and KLF expression was examined by DNA microarray, semi-quantitative real-time PCR, western blot and immunoï¬uorescence analyses. Atorvastatin upregulated KLF expression in EA.hy926 cells in both the quiescent and ox-LDL-induced inflammatory states, suggesting that KLFs were novel participants in the vascular endothelial dysfunction response to ox-LDL. Our study demonstrated that atorvastatin increased both the mRNA and protein levels of KLF in quiescent EA.hy926 cells. Moreover, atorvastatin counteracted the ox-LDL-induced downregulation of KLF expression.