Expression of somatostatin mRNA in various differentiated types of gastric carcinoma

IM METHODS By using in situ hybridization and immunohistochemical techniques, the expression of somatostatin mRNA and somatostatin immunoreactivity in the normal gastric mucosa, the poorly, moderately and welldifferentiated gastric carcinomas, and various clinical stages of carcinoma were observed.RESULTS In comparison with the normal gastric mucosa, the significantly increased expression of somatostatin mRNA positive cells was displayed in gastric carcinoma (t=2681, P<001). The positive signal cells were distributed in a scattered form or aggregated as a mass or a cord, and the positive cells were more significantly enhanced in poorly differentiated carcinomas than those in well and moderately differentiated carcinomas (t=2962, P<001). The somatostatin mRNA hybridization signals in stages Ⅲ and Ⅳ of gastric carcinoma were significantly higher than those in stages Ⅰ and Ⅱ. The results of somatostatin immunoreactivity were consistent with those of in situ hybridization.CONCLUSION The alteration of the expression of somatostatin mRNA was associated with the development of gastric carcinoma and may play an important role in the process of tumor differentiation..

超声波辅助酶法制备北芪菇抽提物及其抗氧化能力研究

为探究北芪菇抽提物制备工艺及抗氧化活性,以氨基态氮含量和可溶性固形物含量为指标,采用单因素实验和响应面法对超声波辅助酶法制取北芪菇抽提物的条件进行优化。结果表明,最佳条件为:纤维素酶用量0.5%、水料比12∶1 mL/g、超声时间40 min、超声温度40℃、pH4.0,抽提物氨基态氮含量(0.765±0.12)mg/mL,总黄酮含量6.5%±0.25%,可溶性固形物含量为2.0%。以VC为阳性对照,抗氧化性结果表明酶法抽提物(EE)具有体外抗氧化活性,清除DPPH自由基的能力最强,当质量浓度为600μg/mL时与同质量浓度的VC标准品相比,清除能力明显高于对照。本研究可为北芪菇的进一步开发应用提供理论依据。