Disparities of conjugating protective enzyme activities in the colon of patients with adenomas and c

来源 :World Journal of Gastroenterology | 被引量 : 0次 | 上传用户:xiaoyezi422
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
AIM:To investigate the metabolic enzymatic capacity of the colon mucosa to detoxify noxious carcinogenic compounds.METHODS:We investigated the activity of 2 conjugating enzymes-the microsomal uridine glucuronosyltransferase(UGT)and the cytosomal glutathione S-transferase(GST)in the uninvolved mucosa of the colon transversum and sigmoideum in patients with adenomatous polyps and colorectal cancer.Biopsies were taken from the mucosa during colonoscopies which were done for clinical(diagnostic)reasons.After storage,the biopsy material was homogenized and after differential centrifugation the enzyme assays were performed with 4-nitrophenol(UGT)and 1-chloro 2,4-dinitrobenzene(GST)as substrates.RESULTS:About 48 patients were included of which28 had adenomas and 20 had colorectal carcinomas confirmed by histopathology.Enzyme activities were expressed as nmol/mg per minute protein for the GST and as pmol/mg per minute protein for the UGT.Analysis of variance(F-test)indicated that both enzymes were more widely distributed in adenoma than in cancer patients.The means±SD were smaller for cancer patients:GST for adenomas 268±152 vs 241±69 for carcinomas and UGT for adenomas 197±200 vs 150±86 for carcinomas.CONCLUSION:Compared to patients with adenomatous colon polyps those with colorectal carcinoma exhibited a lower capacity of detoxifying enzyme metabolism and their activities clustered over a smaller range. AIM: To investigate the metabolic enzymatic capacity of the colon mucosa to detoxify noxious carcinogenic compounds. METHODS: We investigated the activity of 2 conjugating enzymes-the microsomal uridine glucuronosyltransferase (UGT) and the cytosomal glutathione S-transferase (GST) in the uninvolved mucosa of the colon transversum and sigmoideum in patients with adenomatous polyps and colorectal cancer. Biopsies were taken from the mucosa during colonoscopies which were done for clinical (diagnostic) reasons. After storage, the biopsy material was homogenized and after differential centrifugation the enzyme assays were performed with 4-nitrophenol (UGT) and 1-chloro 2,4-dinitrobenzene (GST) as substrates .RESULTS: About 48 patients were included of 28 had adenomas and 20 had colorectal carcinomas confirmed by histopathology. Enzyme activities were expressed as nmol / mg per minute protein for the GST and as pmol / mg per minute protein for the UGT. Analysis of variance (F-test) indicating that both enzymes were more widely distributed in adenoma than in cancer patients. The means ± SD were smaller for cancer patients: GST for adenomas 268 ± 152 vs 241 ± 69 for carcinomas and UGT for adenomas 197 ± 200 vs 150 ± 86 for carcinomas. to patients with adenomatous colon polyps those with colorectal carcinoma exhibited a lower capacity of detoxifying enzyme metabolism and their activities clustered over a smaller range.
其他文献
本文基于Fluent6.1并结合其动网格技术和UDF功能,研究了在雷诺数Re = 100 时振动圆柱的绕流问题。振动圆柱绕流的一个重要特征就是出现锁定现象。首先,给出固定圆柱绕流的数值
会议
本文建立了跌落式冲击机的振动与冲击理论模型,分析下落物体自由振动线性系统特性同随后冲击响应的关系,并将其响应与直接冲击下的物体响应作比较。此外采用通用有限元软件ABAQ
会议
本文综述和总结了与转子系统主动平衡相关的动力学建模和分析方法;转子系统主动平衡理论及技术的发展,特别是变速期间转子的主动平衡理论;介绍了转子主动平衡系统作动器/传感器
本文介绍我公司生产的汽轮发电机,在五十多年的制造和运行过程中曾发生的几个机械振动问题和处理。主要介绍以下内容:转子的动平衡;转子二向刚度不等引起的倍频振动;定子机座的电
本文针对世界上首辆全自动双小车桥吊的工作特点,应用ANSYS 有限元程序对其动态特性进行了计算机仿真分析。计算得到了双小车桥吊结构的固有频率及动力响应。结合分析结果,指出
本文研究了三向网格浅球面网壳,在均布载荷作用下几何非线性的弯曲问题。使用拟壳法得到双层三向网格浅球面网壳的大挠度方程,采用修正迭代法,得到了载荷和中心挠度关系的二次近
本文在输入地震动功率谱为C-P 谱的假设下推导了计算组合系数的解析公式。然后通过功率谱曲线的拟合得到相应的C-P 谱参数,进而使用该解析公式计算组合系数并与数值积分的结果
本文应用摄动随机有限元法研究多自由度随机结构在随机振动输入作用下的动力反应问题。首先, 基于虚拟激励法原理,把多自由度结构体系的复合随机振动方程转化为多自由度确定性
会议
本文将地震动的输入采用了Ramadan 和Novak 提出的方法,同时考虑行波效应和部分相干效应的人工合成多点地震动。在考虑网壳结构材料非线性和几何非线性的基础上,采用大型有限元
会议
本文在设计起重机振动信号采集调理系统时,选取起重机的大梁、起升机构等一些重要位置布置传感器,综合运用传感技术、电子技术,通过在单片机的控制下,使得多路信号采集通道分时、
会议