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1.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(3): 312-319, 2020 May.
Artigo em Chinês | MEDLINE | ID: mdl-32543135

RESUMO

OBJECTIVE: To investigate the effects of short hairpin RNA (shRNA) on the proliferation, invasion, apoptosis and tumor formation of non-small cell lung cancer cisplatin-resistant cell line (A549/DDP) via silencing of colon cancer associated transcript 2 ( CCAT2). METHODS: TA549/DDP cells were transfected with shRNA- CCAT2 (sh- CCAT2) or shRNA-negative control (shRNA-NC), and untransfected A549/DDP cells were used as the control group. CCAT2 mRNA expression in three groups of A549/DDP cells was detected by quantitative real-time PCR (qRT-PCR). The proliferation of three groups of A549/DDP cells treated with different mass concentrations of DDP (0-8 mg/L) was detected by MTT. According to the proliferation experiment results, 2 mg/L was selected as DDP concentration for subsequent experiments. The effects of 2 mg/L DDP treatment on the proliferation, apoptosis, and invasion ability of each group of cells (with untreated A549/DDP cells as the control group) were tested by clone formation experiments, flow cytometry analysis and Transwell experiments. The expression levels of cell proliferation marker proteins (Ki67, PCNA), apoptosis marker proteins (Caspase-3, Caspase-9) and invasion marker proteins (VEGF, MMP-14) were detected by Western blot. Nude mice were injected subcutaneously with A549/DDP cells, A549/DDP cells transfected with shRNA-NC or A549/DDP cells transfected with sh- CCAT2. DDP was intraperitoneally injected at the concentration of 2 mg per kilogram of mice body weight totally for 7 times with an interval of 3 d. A control group was injected subcutaneously with A549/DDP cells, and an equal volume of normal saline instead of DDP was injected intraperitoneally. The tumor volume was detected every 5 d for a total of 30 d. Mice were sacrificed and tumor tissues were taken out 30 d later. CCAT2 mRNA expression level in tumor tissues was detected by RT-PCR, and tumor cell apoptosis was detected by TUNEL staining. RESULTS: Compared with the control group and the shRNA-NC transfection group, the expression level of CCAT2 mRNA was decreased in sh- CCAT2 transfected A549/DDP cells ( P<0.01). The decrease degree of cell proliferation was more pronounced after treating with 2 to 8 mg/L of DDP ( P<0.01). Compared with the control group, in the three groups that treated with DDP, the formation of clones and the expression of proliferation marker proteins Ki67 and PCNA were reduce ( P<0.01), while the rate of apoptosis and the expression of apoptosis marker proteins Caspase-3 and Caspase-9 were increased ( P<0.01). Also, the number of invasion cell and the expression of invasion marker proteins VEGF and MMP-14 were reduced in the three groups that treated with DDP ( P<0.01). Among the three groups of DDP-treated cells, the changes in sh- CCAT2 transfected cells was the most obvious ( P<0.01). Compared with the control group, the tumor volume of the three DDP treatment groups was smaller and the differences were statistically significant at 30 d ( P<0.01). The expression of CCAT2 mRNA was decreased in tumor tissues ( P<0.01), while apoptosis increased ( P<0.01). Among the three DDP treatment groups, the A549/DDP cell group transfected with sh- CCAT2 showed the most notable changes ( P<0.01). CONCLUSION: sh- CCAT2 can inhibit the proliferation of A549/DDP cells, induce apoptosis and reduce the cell invasion ability, thereby inhibiting the growth of A549/DDP cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias do Colo , Neoplasias Pulmonares , RNA Interferente Pequeno , Animais , Antineoplásicos/farmacologia , Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Proliferação de Células , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Pulmonares/genética , Camundongos , Camundongos Nus , RNA Longo não Codificante , RNA Interferente Pequeno/genética
2.
Ying Yong Sheng Tai Xue Bao ; 26(4): 1055-63, 2015 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-26259446

RESUMO

Socio-hydrology is an interdiscipline of hydrology, nature, society and humanity. It mainly explores the two-way feedbacks of coupled human-water system and its dynamic mechanism of co-evolution, and makes efforts to solve the issues that human faces today such as sustainable utilization of water resources. Starting from the background, formation process, and fundamental concept of socio-hydrology, this paper summarized the features of socio-hydrology. The main research content of socio-hydrology was reduced to three aspects: The tradeoff in coupled human-water system, interests in water resources management and virtual water research in coupled human-water system. And its differences as well as relations with traditional hydrology, eco-hydrology and hydro-sociology were dwelled on. Finally, with hope to promote the development of socio-hydrology researches in China, the paper made prospects for the development of the subject from following aspects: Completing academic content and deepening quantitative research, focusing on scale studies of socio-hydrology, fusing socio-hydrology and eco-hydrology.


Assuntos
Conservação dos Recursos Naturais , Hidrologia , Recursos Hídricos , China , Humanos , Água
3.
Ying Yong Sheng Tai Xue Bao ; 25(9): 2716-22, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25757327

RESUMO

The 5th World Conference on Ecological Restoration was held in Madison, Wisconsin, USA on October 6-11, 2013. About 1200 delegates from more than 50 countries attended the conference, and discussed the latest developments in different thematic areas of ecological restoration. Discussions on evaluation of ecological restoration were mainly from three aspects: The construction for evaluation indicator system of ecological restoration; the evaluation methods of ecological restoration; monitoring and dynamic evaluation of ecological restoration. The meeting stressed the importance of evaluation in the process of ecological restoration and concerned the challenges in evaluation of ecological restoration. The conference had the following enlightenments for China' s research on evaluation of ecological restoration: 1) Strengthening the construction of comprehensive evaluation indicators system and focusing on the multi-participation in the evaluation process. 2) Paying more attentions on scale effect and scale transformation in the evaluation process of ecological restoration. 3) Expanding the application of 3S technology in assessing the success of ecological restoration and promoting the dynamic monitoring of ecological restoration. 4) Carrying out international exchanges and cooperation actively, and promoting China's international influence in ecological restoration research.


Assuntos
Recuperação e Remediação Ambiental , China , Congressos como Assunto , Ecologia
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(8): 1713-7, 2008 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-18975786

RESUMO

On-line measurement of size and composition of single particle using an aerosol time-of-flight Laser mass spectrometry (ATOFLMS) had been designed in our lab. Each particle's aerodynamic diameter is determined by measuring the delay time between two continuous-wave lasers, A Nd : YAG laser desorbs and ionizes molecules from the particle, and the time-of-flight mass spectrometer collects a mass spectrum of the generated ions. Then the composition of single particle is obtained. ATOFLMS generates large amount of data during the process period. How to process these data and extract valuable information is one of the key problems for the ATOFLMS. In this paper, the fuzzy clustering used to classify large numbers of mass spectral of air indoor by an ATOFLMS. Each revised spectrum is converted to a normalized 300-point vector, each point representing one mass unit. Then the positive ion mass spectra of a single particle are described as 300-dimensional data vectors using the ion masses as dimensions and the ion signal peak areas as values. The data vectors of all particles measured are written into a classification matrix. Each spectrum's data was stored as one row in this matrix. The Fuzzy c-means algorithm is an iterative method starting the calculation with random class centers to find a substructure in the data. The procedure works in such a way that finally similar objects (particle spectra) have a minimum distance between their corresponding data vectors, on the one hand, and to the center of a cluster, on the other hand. So the aim of the iteration is to find local minima in the N-dimensional space where N is the number of evaluated peak masses. The particle data used in this study were collected over a period one day in Hefei. During the campaign, inorganic salts, mineral particles, and carbonaceous particles, with varying degrees of secondary components, were identified. The detection results of particle size exhibit that aerosol is predominanantly in the form of fine particles, and the particles whose diameter larger than 1 microm are scare. The particles whose diameter less than 1 microm are make up of 95% of the total particles, and these particles are major distributed in 0.4-0.8 microm.

5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(8): 1919-22, 2008 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-18975833

RESUMO

Real-time measurement of size and composition of single soil dust particles using an aerosol time-of-flight laser mas spectrometry (ATOFLMS) was designed in our lab. Each particle's aerodynamic diameter was determined by measuring the delay time between two continuous-wave lasers, a Nd:YAG laser with a 266 nm pulsed output was used to desorb and ionize aerosol particles, and ions formed in the laser desorption/ionization process were accelerated into the time-of-flight drift region where they separated by mass-to-charge ratio, then the composition of single particle was obtained. In the present paper, soil samples were collected from four different areas in China. After the pretreatment and suspension, the particle sample was then transferred to ATOFLMS through a plastic transfer line. During the campaign, a large number of size and mass spectra of single par ticles were obtained. The presence of crustal elements was observed in the mass spectra of individual particles. Iron, potassium aluminum and calcium constitute the two most commonly detected cations. Other common cations observed in the mass spectra o soil particles include magnesium, and sodium. The detection results exhibit that the coarse particles with size of 1-2 microm are dominate in the detected particles. Experimental results show the ATOFLMS have important practical value for researching and monitoring of atmospheric aerosol environment.

6.
Ying Yong Sheng Tai Xue Bao ; 19(4): 859-65, 2008 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-18593050

RESUMO

Based on the theoretical meaning of vulnerability, a vulnerability assessment of eco-econom in fifteen counties in the northern slope region of Tianshan Mountains was conducted. The ecosystem services change to land use was regarded as the impact, and based on the fourteen indices from resource holding, society development, and economy development statistic data, the adaptive ability was evaluated by using the methods of analytic hierarchy process (AHP) and fuzzy synthetic evaluation. On the basis of assessment results of impact and adaptive capacity, the fifteen counties were divided into five classes under the assessment principles, and the district with higher-class number was of more vulnerability. The first class included Usu City and Changji City, the second class included Hutubi County, Miquan County, Fukang City, Jimsar County, Qitai County and Mori Kazak Autonomous County, the third class included Karamay City and Urumqi City, the fourth class included Kuitun City and Shawan County, and the fifth class included Jinghe County, Shihezi City and Manas County. The vulnerability reflected the level of eco-environment change and socioeconomic development, and the vulnerability assessment could be a good way to ensure the sustainable development. Aiming to decrease the vulnerability, various districts belonging to different class of vulnerability should establish relevant tactics according to the vulnerability factors to accelerate the region's sustainable development.


Assuntos
Ecologia/economia , Planejamento Ambiental , Monitoramento Ambiental/métodos , Algoritmos , China , Monitoramento Ambiental/estatística & dados numéricos , Lógica Fuzzy , Sistemas de Informação Geográfica/estatística & dados numéricos , Geografia , Modelos Teóricos
7.
J Environ Sci (China) ; 16(3): 436-42, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15272719

RESUMO

The purpose of this article is to identify the effect of land-use pattern on rainfall-runoff and runoff-sediment relations in Zichang Watershed of the Loess Plateau. From 1986 to 1997, many farmlands changed into grassland or woodland, especially the farmland in steep slope positions or far away from the river. The change of land-use pattern altered the rainfall-runoff and runoff-sediment relationships, and led to higher slope of trend curves (STCs) of annual rainfall-runoff mass curve and runoff-sediment mass curve in 1990s than that in 1980s. It is implied that more soil and water loss yielded in 1990s. In order to reduce soil loss, more attentions should be paid to land-use pattern and some grass or other herbaceous filter strips should be built along rivers.


Assuntos
Conservação dos Recursos Naturais , Sedimentos Geológicos/análise , Chuva , Solo , Movimentos da Água , Agricultura , China , Ecossistema , Monitoramento Ambiental , Filtração
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