The point mutation of p53 gene exon7 in hepatocellular carcinoma from Anhui Province,a non HCC prevalent area in China

AIM: In hepatocellular carcinoma (HCC) prevalent areas of China, the point mutation of p53 exon7 is highly correlated with Hepatitis B virus(HBV) infection and aflatoxin B intake. While in non-HCC-prevalent areas of China, these factors are not so important in the etiology of HCC. Therefore, the point mutation of p53 exon7 may also be different than that in HCC-prevalent areas of China. The aim of this study is to investigate the status and carcinogenic role of the point mutation of p53 gene exon7 in hepatocellular carcinoma from Anhui Province, a non-HCC-prevalent area in China. METHODS: PCR PCR-SSCP and PCR-RFLP were applied to analyze the homozygous deletion and point mutation of p53 exon7 in HCC samples from Anhui, which were confirmed by DNA sequencing and Genbank comparison. RESULTS: In the 38 samples of hepatocellular carcinoma, no homozygous deletion of p53 exon7 was detected and point mutations of p53 exon7 were found in 4 cases, which were found to be heterozygous mutation of codon 249 with a mutation rate of 10.53%(4/38). The third base mutation(G-T) of p53 codon 249 was found by DNA sequencing and Genbank comparison. CONCLUSION: The incidence of point mutation of p53 codon 249 is lower in hepatocellular carcinoma and the heterozygous mutation of p53 exon7 found in these patients only indicate that they have genetic susceptibility to HCC. p53 codon 249 is a hotspot of p53 exon7 point mutation, suggesting that the point mutation of p53 exon 7 may not play a major role in the carcinogenesis of HCC in Anhui Province, a non-HCC-prevalent area in China.

Removal of copper from a copper sulphate solution using an ultrasonic-electrolysis process

The application of ultrasonic\|electrolysis process for the removal of copper is studied. In the ultrasonic field cavitation acts as jets and agitates the solution and breaks the barrier layer between the cathode surface and the bulk of the solution. Thus increases metal deposition on the cathode surface. The results show that an ultrasonic field is successful for the removal of low copper concentrations in solution.

在铝合金活塞裙上涂覆聚合物复合材料和Nil陶瓷复合材料与铸铁缸孔磨损及刮伤的特点

本研究的目的是评估涂层活塞裙与铝合金缸孔和铸铁缸孔配合的相容性和摩擦学行为。分别对铝活塞裙涂覆了多聚物复合材料和Ni-陶瓷复合材料进行了研究，在Ni-陶瓷复合材料涂覆活塞裙中，无论是铸铁缸孔还是铝缸孔Ni-P-BN表现出稳定的低磨损特点。镀锡活塞裙在铸铁缸孔和390铝缸孔中的磨损较少，但是在413铝合金和356铝合金缸孔中磨损较多。所有的多聚物复合材料涂覆的活塞裙与无论Ni-p-SiC或Ni-P-Si／3N／4陶瓷复合材料涂覆活塞裙相比在铸铁缸孔和铝合金缸孔中的磨损都很小。甚至在413铝合金和356铝合金缸孔中也表现出较小的磨损深度。在多聚物复合涂层中，有两种不同二硫化钼含量和石墨颗粒含量的树脂涂层获得了390铝合金缸孔中的最小磨损量，将多聚物复合涂层用在阳极硬化处理过的活塞裙上，与单独使用多聚物复合涂层相比磨损进一步降低，并且更加稳定。用刮磨试验条件来模拟缺油条件下的磨损，结果发现，多聚物涂层有内在的抗刮伤能力。但是耐久性不好。Ni-P-BN涂层有内在的抗刮伤能力并且耐久性也较好。在无润滑条件下与390铝合金滑动摩擦试验中发现，在阳极硬化后再增加多聚物涂层表现出良好的涂层耐久性和良好的抗刮伤能力。