Search

An improved Apriori algorithm for association rule mining called Apriori-BR was proposed,which was based on bit operation and reverse index.Specifically,the reverse index from frequent itemsets to transactions was constructed firstly by scanning twice of database,and the reverse index was grouped by the length of transactions.Then in the mining process,bit operation was adopted to accelerate subset detection together with the dynamical elimination of invalid low-dimensional transactions.The numerical results show that the Apriori-BR proposed can substantially improve mining efficiency when compared with the conventional Apriori algorithm and the improved ones in the literature.

Objective To investigate the expression and clinical significance of silent information regulator 2 (SIRT2) form tissue of urothelial bladder cancer(UBC) and the effects of down-regulation of SIRT2 on the proliferation, invasion and migration of bladder cancer cells. Methods The expression of SIRT2 protein was detected in 95 samples of urothelial bladder cancer tissues and 39 paracancerous tissues using the immunohistochemical EnVision method. Its relationship with clinicopathological parameters was analyzed. The expression of SIRT2 mRNA in bladder cancer cell lines was detected by RT-qPCR, and the expression levels of SIRT2 protein in bladder cancer cell lines, 12 pairs of fresh bladder cancer tissues were detected by Western blot. Lentiviral infection was used to stably downregulate the SIRT2 gene in bladder cancer cell line T24. CCK8 and cell colony assays were performed to detect changes in cell proliferation ability and Transwell assay to detect changes in cell invasion and migration activity. Results The positive expression rate of SIRT2 in urothelial bladder cancer tissues was 84%(80/95), which was higher than that in normal uroepithelial tissues (5%, 2/39) (PConclusions SIRT2 is highly expressed in bladder uroepithelial carcinoma, and interfers with SIRT2 significantly and so inhibites bladder cancer cell proliferation, invasion and migration.