Inhibitory effects of four plants flavonoids extracts on fatty acid synthase

Fatty acid synthase (FAS) had been found overexpress and hyperactive in most cancers. Pharmacological inhibitors of FAS activity preferentially repress cancer cell proliferation and induce cancer cell apoptosis without affecting nonmalignant fibroblasts. These made FAS an excellent drug target for cancer therapy. The activity of FAS in 11 different kinds of cancer cells, including esophageal carcinoma (EC109, EC8712, H5E973), gastric carcinoma (N87, BGC823), lung carcinoma (A549, 95-D), hepatoma (HepG2), uterine cervix cancer (HeLa) and leukaemia (K562, U937) were compared using spectrophotometric method. We selected the cell line with the highest FAS activity as cell model to study the inhibitory effect of the flavonoids extracts on FAS. Four plants including Canavium album Raeuseh leaves, Bombax ceiba Linn, Brassica albograbra Bailey, and Citrus reticulata Blanco were selected for extracting flavonoids. The results showed significantly different FAS activity among different cancer cells. The FAS activity is the lowest in gastric cancer cell N87 (15.91 ± 3.61 U/mg protein) and the highest in lung cancer cell A549 (127.36 ± 10.14 U/mg protein). The cancer cell A549 was used as cell model to test the inhibitory effort of flavonoids extracts on FAS. Results showed that the flavonoids extracts of Citrus reticulata Blanco and Canavium album Raeuseh leaves have higher inhibitory effect on FAS activity compared with the universally used FAS inhibitor C75 and both extracts inhibit cancer cell proliferation when added to cultured cancer cells. These studies provided a good cell model for testing the inhibitory effect on FAS activity and suggested that Citrus reticulata Blanco rind and Canavium album Raeuseh leaves are good biomaterials for separating and purifying natural flavonoids FAS inhibitors and exploring their inhibitory mechanisms.     

金刚石钻进规程的实验室模拟及参数校核

金刚石钻进的钻进规程决定了钻进效率和钻头的使用寿命，也决定了钻进的安全性、可靠性和经济效益。因此，选择最佳的钻进规程尤其重要。本文通过智能微钻实验台对金刚石钻进的模拟钻进参数及其变化曲线、参数值，以及对应的钻进速度、进尺变化曲线、参数值进行分析，得到相应岩石条件下的最优钻进规程。     

酸雨(水)对地质环境的影响研究及其意义

酸雨沉降对地质环境产生危害.地质体(岩石、矿物)为酸雨敏感性研究不可或缺的组成部分.开展地质环境对酸雨危害降解效应的研究具有重要的理论与现实意义.     

几种阴阳离子对磷钨酸光催化降解甲基橙的影响

以磷钨酸为光催化剂,在紫外灯照射下,对甲基橙溶液进行光催化降解,考察了几种阴阳离子对磷钨酸光催化降解甲基橙溶液的影响。结果表明：Mg^2＋、Ca^2＋、NO3^-、SO4^2-和CO3^2-均对催化活性有促进作用,其中Mg^2＋和Ca^2＋仅有微弱的促进作用;NO3^-和SO4^2-随着浓度的增加促进作用也有所增加;CO3^2-则随着浓度的增加促进作用呈下降趋势;Mn^2＋、Al^3＋和Cl^-对光解反应存在较强的抑制作用,且Al^3＋和Cl^-随着其浓度的增加,抑制作用增强。     

环保评价标准和监督管理技术规范中环境监测信息的确认方法

近年来,各类环保评价标准和监督管理技术规范不断推陈出新,其中对环境监测的要求不断明晰。本文结合环境管理要求,围绕着环保评价标准和监督管理技术规范的特点,对其中的环境监测信息进行分析,提出确认思路和程序,并选取实例进行应用效果分析。     

等面积法确定翻边预冲孔直径

介绍了钢板翻边工艺中预冲孔直径的等面积计算与工艺验证结合的确定方法。采用这种方法 ,可以保证翻边成形后工件的尺寸要求 ,对于精度高、批量大的产品加工很有意义     

Performance evaluation of the effect of humic acid on Anammox granular sludge:Apparent morphology,nitrogen removal and microbial community

Humic acid(HA)is a typical refractory organic matter,so it is of great significance to investi-gate its effect on the performance of Anammox granular sludge.When the dosage of HA ≤ 50 mg/L,HA promotes the total nitrogen removal rate(NRR)to 1.45 kg/(m3·day).When HA was between 50 and 100 mg/L,the NRR of Anammox was stable.At this time,the adsorption of HA causes the sludge to gradually turn from red to brown,but the activities of heme and en-zymes showed that its capacity was not affected.When HA levels reached 250 mg/L,the NRR dropped to 0.11 kg/(m3·day).Moderate HA levels promoted the release of extracellular poly-meric substance(EPS),but excessive HA levels lead to a decrease in EPS concentrations.HA inhibited Anammox activity,which indirectly hindered the transmission of substrate and accumulated substrate toxicity.Although HA promoted the increase of heterotrophic micro-bial abundance in Anammox system,the microbial diversity decreased gradually.With the increase of HA concentration,the abundance of Candidatus_Brocadia,the main functional microorganism of Anammox system,decreased gradually,while the abundance of Candida-tus_Kuenenia increased gradually.     

De novo biosynthesis of Δ3-Isoxazolin-5-one and 3-Nitropropanoic acid derivatives inChrysomela tremulae

The nature of the cosmic redshift is one of the most fundamental questions in modern science. Hubble's discovery of the apparent Expansion of the Universe is derived from obsevations on a small number of galaxies at very low redshifts. Today, quasar redshits have a range more than 1000 times greater than those in Hubble's sample, and represent more than 100 times as many objects. A recent comprehensive compilation of published measurements provides the basis for a study indicating that quasar observations are not in good agreement with the original predictions of the Expanding Universe theory, but are well fit by the predictions of an alternative theory having fewer adjustable parameters.