Objectives To explore the relationship between the extension force deficiency of the lower extremity and fall risks among the senior female,so as to reveal the potential factors contributing to fall.Methods Forty community-dwelling senior females aged 65 and older were assigned to the group of fallers or non-fallers according to their reported fall history and measured fall risk index (FRI).Extension force of the lower extremity was measured through 3-consecutive fast squats on a force platform.The time for 3m-time up and going (TUG),as well as static and dynamic balance were also measured.Results Compared to the non-fallers,the fallers showed lower peak extension force per body weight (PEF/BW) of the left leg and larger asymmetry of the peak extension force per body weight between the two legs in squats.Correlation analysis showed that FRI had a strong negative relation with PEF/BW of the left leg and a strong positive relation with extension force asymmetry/body weight.Also time for 3m-TUG was positively related to all the force variables standardized by the body weight,especially for the left leg.However,the analysis failed to find a relationship between the velocity of the center of pressure (COP) sway on static balance and any force variables.In addition,PEF/BW of the left leg decreased and force asymmetry/body weight between the two legs increased with aging.Conclusion Extension force measurement in squat is an effective way to assess the muscle strength deficiency related to the increased fall risk.The extension force of the lower extremity to support the body weight in squat had a strong relation to the function decline in the dynamic balance,which contributes greatly to fall risk.The extensive force asymmetry in squat between the two legs is another important fall risk factor for the senior females.

To examine the substrate specificity of carotenoid 3',4'-desaturase (DR2250) from Deinococcus radiodurans, we amplified the dr2250 gene by using PCR methods. The PCR products were digested by Hind III-BamH I and ligated into the vector pUC19, yielding recombinant vector pUC-CRTD. We analyzed the carotenoids of E. coli transformants containing pACCRT-EBI(Eu) and (or) pRK-CRTC and (or) pUC-CRTD. Our results demonstrated that DR2250 had substrate specificity on the carotenoids with hydroxyl group at C1 (1').
Carotenoids ; biosynthesis ; genetics ; metabolism ; Deinococcus ; enzymology ; genetics ; Escherichia coli ; genetics ; metabolism ; Oxidoreductases ; metabolism ; Substrate Specificity

Objective To construct the Wip1 gene recombinant lentiviral expression vector and to investigate its effects on breast cancer cell biological behaviors .Methods Wip1 gene short hairpin RNAs (shRNA) was transfected into breast cancer MCF-7 cells through lentiviral infection method .Wip1 mRNA and protein expressions before and after transfection were detected by u-sing qRT-PCR and Western blotting .The effects of Wip1-shRNA on the proliferation ,apoptosis ,cell cycle ,invasion and metastasis in MCF-7 cells were determined by using the MTT assay ,flow cytometry and transwell invasion test .Interfering RNA molecule p53dsRNA inhibiting p53 gene expression (p53 dsRNA) was screened ,and the effect of p53 inhibition on MCF-7 cells invasion and metastasis was analyzed .Results After transfection for 48 h ,the cellular fluorescence in the Wip1-shRNA group was stronger , while which in the NC-shRNA group was weaker .Cellular Wip1 mRNA and protein expressions in the Wip1 shRNA group were 0 .291 ± 0 .025 and 0 .203 ± 0 .021 respectively ,which in the NC-shRNA group were 0 .954 ± 0 .090 and 0 .963 ± 0 .092 respectively , the difference between the two groups was statistically significant (P<0 .05) .The cellular survival rate at various time points had statistical difference between the two groups (P<0 .05) .The early and late cell apoptosis number in the NC-shRNA group was less than that in the Wip1-shRNA group ,the difference was statistically significant (P<0 .05) .The cells numbers at phase G0 +G1 and phase S in the NC-shRNA group were 53 .5 ± 3 .6 and 27 .3 ± 1 .5 respectively ,which in the Wip-shRNA group were 72 .3 ± 5 .2 and 14 .6 ± 0 .8 respectively ,the difference was statistically significant(P<0 .05) .The Transwell invasion and metastasis results showed that the cell transmembrane number in the NC-shRNA group was more than that in the Wip1-shRNA group(P<0 .05) .The cellu-lar p53 mRNA and protein expression had statistical difference between the control group and p53dsRNA group(P<0 .05) .Conclu-sion RNA interference can effectively suppress Wip1 expression in MCF-7 cells .Wip1 may affect the proliferation ,apoptosis ,cell cycle ,invasion and metastasis of breast cancer cells by modulating protein expression .p53dsRNA increases the invasion and metas-tasis ability of breast cancer MCF-7 cells by interfering p53 gene down-regulation .