Over-expression of APP and Swedish mutation could cause some familial early onset AD. In this study, a primary screening was conducted of effective small interference RNAs (siRNAs) targeted wild type APP (APPwt) and Swedish mutant APP (APPswe). One siRNA targeting APPwt and the other siRNA targeting APPswe were designed. All these siRNAs were endogenously expressed by siRNAs expressing plasmids. COS-7 cells were transiently co-transfected with APP-GFP recombinant plasmids and siRNA expression vector. The silencing effect of each siRNA was quantitatively assessed by the level of expression of green fluorescent protein (GFP). It was found that the siRNAs silenced APPwt and APPswe to different degrees. siRNA directed against APPswe was more effective in suppressing the expression of fusion gene of APPswe than that of APPwt. The silencing effect of siRNA directed against APPswe indicating allele-specific silencing property of the siRNAs. Therefore, siRNAs directed against APP play an important role both in the therapeutic study of Alzheimer disease and functional exploration ofAPP gene.

Objective To compare the dosimetric differences of four fluence smoothing (FS) levels of the Monaco system in intensity-modulated radiation therapy (IMRT) after rectal cancer surgery, and to provide a reference for FS selection in clinical practice. Methods A total of 15 postoperative patients with rectal cancer admitted in 2020 were selected. Under the same optimal conditions, FS was set to Off, Low, Medium, and High for IMRT planning. The data were analyzed by SPSS 20.0 software. The dosimetric parameters of planning target volume and organs at risk (OARs), the number of Segments, the number of monitor units (MUs), the estimated total delivery time (ETDT), and the gamma pass rate were compared between the four FS levels. Results The four FS levels resulted in clinically acceptable dosimetric parameters of the planning target volume and OARs, and there was no significant difference in dose distribution between FS levels. From FS-Off to FS-High, number of Segments, number of Mus, and ETDT decreased by 15.2%, 11.8%, and 6.7%, respectively, whereas gamma pass rate increased by 1.6%. Conclusion The IMRT plans at four FS levels can meet the clinical requirements. Considering the planning quality and execution efficiency, FS-High is recommended for postoperative IMRT of patients with rectal cancer.

Over-expression of APP and Swedish mutation could cause some familial early onset AD.In this study, a primary screening was conducted of effective small interference RNAs (siRNAs) targeted wild type APP (APPwt) and Swedish mutant APP (APPswe). One siRNA targeting APPwt and the other siRNA targeting APPswe were designed. All these siRNAs were endogenously expressed by siRNAs expressing plasmids. COS-7 cells were transiently co-transfected with APP-GFP recombinant plasmids and siRNA expression vector. The silencing effect of each siRNA was quantitatively assessed by the level of expression of green fluorescent protein (GFP). It was found that the siRNAs silenced APPwt and APPswe to different degrees. siRNA directed against APPswe was more effective in suppressing the expression of fusion gene of APPswe than that of APPwt. The silencing effect of siRNA directed against APPswe indicating allele-specific silencing property of the siRNAs. Therefore, siRNAs directed against APP play an important role both in the therapeutic study of Alzheimer disease and functional exploration of APP gene.