苜蓿皂苷提取物对BRL细胞Ldlr、LXRα和FXR mRNA表达的影响（英文） Xin-ping LIANG Dong-qiang ZHANG Yan-yan CHEN Rui GUO Jie WANG Cheng-zhang WANG Ying-hua SHI
浙江大学学报：B卷英文版,
2015, Letnik:
16, Številka:
6
Journal Article
Recenzirano
目的：分析苜蓿皂苷提取物对正常和脂变Buffalo大鼠肝细胞（BRL细胞）中Ldlr、LXRα和FXR m ...RNA表达的影响,进而初步探讨苜蓿皂苷调节脂质代谢及降低机体胆固醇含量的机制。创新点：苜蓿皂苷具有调节脂质代谢,降低机体胆固醇含量的作用,但是目前对其机理研究并不多,特别是在细胞水平上。本试验以BRL细胞为对象,研究苜蓿皂苷对胆固醇代谢相关基因表达的影响,从而探究苜蓿皂苷在细胞水平上对胆固醇代谢的调节作用。方法：通过50%胎牛血清诱导BRL细胞48 h建立细胞脂肪变性模型,运用实时荧光定量聚合酶链式反应（q RT-PCR）检测正常和脂变BRL细胞Ldlr、LXRα和FXR m RNA的表达,从而得出各处理组BRL细胞内Ldlr、LXRα和FXR m RNA表达的变化。结论：（1）添加苜蓿皂苷后,正常BRL细胞中Ldlr m RNA的表达量显著上调,脂变BRL细胞Ldlr m RNA的表达有增加的趋势;（2）苜蓿皂苷可以显著下调正常和脂变BRL细胞中LXRα和FXR m RNA的表达。因此,在细胞水平上,苜蓿皂苷可能通过促进Ldlr的表达,抑制LXRα和FXR的表达,从而调节BRL细胞胆固醇的代谢。
Objective: To describe the trajectory of BP across a 30-year span and evaluate its association with carotid intima–media thickness (CIMT) and brachial-ankle pulse wave velocity (baPWV) by middle age. ...Design and method: 4623 participants aged 6–18 years, recruited from the ongoing cohort of Hanzhong Adolescent Hypertension study, a total of 2780 subjects were followed up for 6 visits over 30 years, and 1925 participants with complete CIMT and baPWV data were used for final analyses. Systolic and diastolic BP trajectories were identified by latent mixture modeling. Results: We identified 5 distinct systolic BP (SBP) trajectories as: “low-stable” (n = 512, 26.6%), “moderate-stable” (n = 993, 51.6%), “high-stable” (n = 229, 11.9%), “moderate-increasing” (n = 152, 7.9%) and “high-increasing” (n = 39, 2.0%). The levels of CIMT and baPWV were linearly increased from low stable- to high-increasing SBP trajectories. A total of 85 individuals and 425 participants developed high CIMT and high baPWV by 2017, respectively. Compared with the low-stable SBP trajectory group, the high-increasing group had increasingly greater odds of high CIMT by middle age in the full adjustment OR = 5.04(1.76–14.44). Such association was observed in diastolic BP trajectories OR = 3.61(1.11–11.70). Conclusions: BP trajectories derived from childhood to middle age vary, and higher BP trajectories were associated with an increased risk of subclinical vascular damage in middle age. Monitoring trajectories of BP from childhood may help identify a high cardiovascular risk population in early life.
It is essential to develop a cheap, recyclable, and efficient photocatalyst to help degrade pollutants contaminating the environment. Herein, mesoporous molecular sieve titanium phosphate （MMS-TiP） ...was used as an efficient nano-photocatalyst to degrade 2,4-dichlorophenol （2,4-DCP） and to oxidize CO. The catalyst was successfully synthesized by a simple and convenient hydrothermal method in the presence of a tri-block copolymer surfactant. Exceptional photoactivity of the optimized MMS-TiP mainly depends on its porous structure, with a large surface area by means of O2 temperature-programmed desorption curves and fluorescence spectra related to the amounts of produced hydroxyl radical. Interestingly, the photocatalytic activity of the prepared MMS-TiP could be greatly improved by coupling with nanocrystalline SnO2. This is likely due to the increase in the lifetime and separation of photogenerated charges by transferring electrons to SnO2 and was observed by steady-state surface photovoltage spectra and time-resolved surface photovoltage responses. The SnOa-coupled MMS-TiP exhibits better photocatalytic performance for 2,4-DCP degradation and better self-settlement than those of the commercial catalyst P25 TiO2. Moreover, it was confirmed by radical-trapping experiments that ·O2^- is the main activated species for the photocatalytic degradation of 2,4-DCP, and is photogenerated by electron transfer from MMS-TiP to SnO2. Furthermore, the main intermediates in the degradation of 2,4-DCP, like parachlorophenol superoxide and 1,2-benzenediol superoxide radicals, were detected, and a possible decomposition pathway related to ·O2^- attack is proposed. These experimental results provide new strategies for developing a recyclable molecular sieve- based nano-photocatalyst with high photocatalytic activity for environmental remediation.
In this paper, taking precision cotton planting system as an example, from the three technology links of the precision agriculture cultivation management information system, including agricultural ...acquisition system information, information processing system, and implementation of the system to start, combine with the technology ideas, methods and means adopted by the precision cotton cultivation research as well as its preliminary results in the trial area. Then, design and develop the integrated managing information systems for the precision cotton cultivation, basing on the farmland information collecting system. It can provide a reference model for precision cotton cultivation in the other regions.
Since most typical alloys in industrial applications are multicomponent with three or more components, and various CA models proposed in the past mainly focus on the binary alloys, a two-dimensional ...modified cellular automaton model allowing for the quantitatively predicting dendrite growth of multicomponent alloys in the low P6clet number regime is presented. The elimination of the mesh-induced anisotropy is achieved by adopting a modified virtual front tracking method. A new efficient method based on the lever rule is applied to calculate the solid fraction increment of the interfacial cells. The thermodynamic data such as liquidus temperature, the partition coefficients, and the slope of liquidus surface, needed for determining the dynamics of dendrite growth, are obtained by coupling with PanEngine. This model is applied to simulate the dendrite morphology and microsegregation of A1-Cu-Mg temary alloy both for single and multi- dendrites growth. The simulated results demonstrate that the difference of the concentration distribution profiles ahead of the dendrite tip for each alloying element mainly results from the different partition coefficients and solute diffusion coefficients. Comparison with the prediction of analytical model is carded out and it reveals the correctness of the model. Consequently, the difference in interdendritic microsegregation behavior of different components is analyzed.
Based on the daily management of water conservancy projects in large basin, one of very effective methods is to use the three-dimensional (3D) geographic information system (GIS), which can greatly ...improve efficiency and cut down the costs resulted from the large area, complicated situation of terrain, and the higher overhead expenses. However, the most frustrating barriers to the widespread use of 3D GIS is the additional difficulty in 3D navigation. The previous research on 3D GIS is reviewed at these aspects of various domains including precision agriculture and digital river. In order to solve the problem, a holistic resolve treated longitude and latitude as a link between 2D and 3D GIS application to achieve the parameters of a link each other, which is designed according to the actual characteristics of basin simulation system construction based upon a uniform programming framework. This method not only achieves the real-time navigation of virtual 3D geographical scenes but also makes it mapping the geographical coordinates in 2D navigation map and 3D GIS application one. And become real in a basin simulation system too. In this paper, its fundamental idea, implementation techniques and application analysis of the Tarim river simulation system as a case are discussed. Presently, it has been applied in simulation management of the Tarim river basin and shows high facility and efficiency.
The main purpose of this study is to examine the fluctuation characteristics of natural Populus euphratica community under surface overtopping artificial disturbance in the lower reaches of the Tarim ...River, China. According to the representative plot sampling method and grid sampling method, sampling sites were conducted and investigated. Selecting plant community structure, species diversity and dominant species as the characterized values of community fluctuations, the influence of surface overtopping disturbance on the P. euphratica community was studied. The main results are shown as follows. The species composition is changed a lot in P. euphratica community under surface-water overtopping disturbance. Species numbers and richness are increased in community after the influence of the disturbance. On the other hand, community structure transform simple into power to complex. And the vertical stratification tends to increase under the disturbance. After the disturbance, species diversity of P. euphratica community has great change. And both the species richness and species diversity are increased obviously while species evenness is appreciably decreased in P. euphratica community. Based on the data, the dominant species is selected from community. During the fluctuation process of community, species composition and community structure transform simple into complex significantly in P. euphratica community under disturbance. The amount of community (e.g. species richness) and species diversity are increased during the process of community change. It shows that the surface water supplement is an effective measure to make P. euphratica community positively fluctuate.
In this paper, the niche breadth and overlap value of dominant species is calculated and analyzed along the community gradients to study population dynamics in the protection forest, Xinjiang, China. ...The main results are as follows. After four years, the amount of populations are increasing as a result of some local species naturally occurred or invaded. And seven dominant species including three native local species were selected from artificial-natural communities. Seven years later, Tamarix ramosissima becomes dominant species while P. communis was absent and H. glomeratus became subdominant species in communities under water stress-tolerant condition. And populations are decreased. The niche breadths of dominant species are ordered. Among dominant species, the niche overlap value between C. caput-medusae and P. euphratica is always the largest one. In addition, there is no relation between niche breadth and niche overlap of dominant species in community basing on the years data analysis, which is not in accordance with previous papers.
Due to the extensive application of Al-Si alloys in the automotive and aerospace industries as structural components, an understanding of their microstructural formation, such as dendrite and（Al＋Si） ...eutectic, is of great importance to control the desirable microstructure, so as to modify the performance of castings. Since previous major themes of microstructural simulation are dendrite and regular eutectic growth, few efforts have been paid to simulate the irregular eutectic growth. Therefore, a multiphase cellular automaton（CA） model is developed and applied to simulate the time-dependent Al-Si irregular eutectic growth. Prior to model establishment, related experiments were carried out to investigate the influence of cooling rate and Sr modification on the growth of eutectic Si. This CA model incorporates several aspects, including growth algorithms and nucleation criterion, to achieve the competitive and cooperative growth mechanism for nonfaceted-faceted Al-Si irregular eutectic. The growth kinetics considers thermal undercooling, constitutional undercooling, and curvature undercooling, as well as the anisotropic characteristic of eutectic Si growth. The capturing rule takes into account the effects of modification on the silicon growth behaviors.The simulated results indicate that for unmodified alloy, the higher eutectic undercooling results in the higher eutectic growth velocity, and a more refined eutectic microstructure as well as narrower eutectic lamellar spacing. For modified alloy, the eutectic silicon tends to be obvious fibrous morphology and the morphology of eutectic Si is determined by both chemical modifier and cooling rate. The predicted microstructure of Al-7Si alloy under different solidification conditions shows that this proposed model can successfully reproduce both dendrite and eutectic microstructures.
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