To construct a recombinant attenuated Salmonella strain carrying the p57 and BLID genes and to evaluate its inhibitory effect on breast cancer cells and apoptosis induction in vitro,the recombinant attenuated Salmonella LH430/pEGFP-p57-BLID was constructed.RT-PCR and Western blot were used to detect the transcription and expression of the recombinant attenuated Salmonella in cancer cells.The CCK-8 method was used to assess the safety of the recombinant at-tenuated Salmonella and its impact on the activity of breast cancer cells.The cell scratch assay was used to analyze the influence of the recombinant attenuated Salmonella on the migratory ability of cancer cells.Flow cytometry and Western blot were used to analyze the effect of the recombinant attenuated Salmonella on the apoptosis of MDA-MB-231 cells.The bands of target genes carried by the recombinant attenuated Salmonella could be amplified by PCR,and these target genes could be transcribed and expressed in MDA-MB-231 cells.The recombinant attenuated Salmonella showed good growth characteristics and genetic stability.Compared with the PBS group,recombi-nant attenuated Salmonella LH430/pEGFP-p57-BLID significantly reduced(P＜0.01)the activity of MDA-MB-231 cells and significantly inhibited(P＜0.01)the migration of MDA-MB-231 cells.Recombinant attenuated Salmonella LH430/pEGFP-p57-BLID can obviously increase the number of apoptosis in MDA-MB-231 cells,significantly upregulate(P＜0.01)the expression of apoptotic protein Bax,and significantly downregulate(P＜0.01)the expression of apoptotic protein Bcl-2.The results showed that the recombinant attenuated Salmonella had an inhibitory effect on breast cancer MDA-MB-231 cells and could induce apoptosis,which laid a foundation for the subsequent study of anti-tumor in vivo.

To construct a recombinant attenuated Salmonella strain carrying the p57 and BLID genes and to evaluate its inhibitory effect on breast cancer cells and apoptosis induction in vitro,the recombinant attenuated Salmonella LH430/pEGFP-p57-BLID was constructed.RT-PCR and Western blot were used to detect the transcription and expression of the recombinant attenuated Salmonella in cancer cells.The CCK-8 method was used to assess the safety of the recombinant at-tenuated Salmonella and its impact on the activity of breast cancer cells.The cell scratch assay was used to analyze the influence of the recombinant attenuated Salmonella on the migratory ability of cancer cells.Flow cytometry and Western blot were used to analyze the effect of the recombinant attenuated Salmonella on the apoptosis of MDA-MB-231 cells.The bands of target genes carried by the recombinant attenuated Salmonella could be amplified by PCR,and these target genes could be transcribed and expressed in MDA-MB-231 cells.The recombinant attenuated Salmonella showed good growth characteristics and genetic stability.Compared with the PBS group,recombi-nant attenuated Salmonella LH430/pEGFP-p57-BLID significantly reduced(P＜0.01)the activity of MDA-MB-231 cells and significantly inhibited(P＜0.01)the migration of MDA-MB-231 cells.Recombinant attenuated Salmonella LH430/pEGFP-p57-BLID can obviously increase the number of apoptosis in MDA-MB-231 cells,significantly upregulate(P＜0.01)the expression of apoptotic protein Bax,and significantly downregulate(P＜0.01)the expression of apoptotic protein Bcl-2.The results showed that the recombinant attenuated Salmonella had an inhibitory effect on breast cancer MDA-MB-231 cells and could induce apoptosis,which laid a foundation for the subsequent study of anti-tumor in vivo.

Objective To analyze the related factors of foot blisters caused by long-distance weight-bearing march and to explore the pathogenesis of foot blisters to provide a useful way for the prevention and treatment.Methods After the 300 km march,counted the number who had accomplished the march,and then recorded the number of foot blisters,location of blisters,and abrasion of sole.Collected the data of gender,age,body mass index (BMI),hand dominance,and whether had bliters before the march through questionnaire.And the data were coded for analysis with SPSS 13.0 statistical package.Results The 7 cases who complete the whole march and 17 cases who already had foot blisters before the march were ruled out of the final statistics.Among the remaining 590 cases,there were 554 cases (93.9%)suffered from foot blisters.And there were 1 282 blisters in total,among which the plantar blisters occupied 98% (1 257 cases).The analysis showed that the incidence of foot blisters had no significant correlation with gender,left/right foot,hand dominance,BMI and age.The predilection sites of blisters were the second and third metatarsals (28.2%),the hallux (21.3%),the fifth metatarsal (18.1%),and the calcaneus (15.8%)of the left foot.The predilection sites of blisters were the second and third metatarsals (33.3%),the hallux (22.4%),the fifth metatarsal (18.6%),and the calcaneus (14.5%)of the right foot.In terms of the abrasion of sole,the lateral heel was worn out the most (34.6% on the left and 34.2% on the right).Conclusion The study confirmed that the incidence of foot blisters had no significant correla-tion with gender,left/right foot,hand dominance,BMI and age,which may be affected by the particularity of this march.Most of the foot blisters occurred in the planta,and the predilection sites of blisters were in accord with sites of of the abrasion of sole and the distribution of plantar shear force,which demonstrated the shear force is the most critical factor on the pathogenesis of foot blisters.