Objective To study the effect of different concentration of 1,25-dihydroxyvitamin D3[1,25(OH)2D3] on cell proliferation,differentiation and the expression of vitamin D receptor (VDR) in mouse MC3T3E1 osteoblast.Methods Osteoblast were cultured in medium with different concentrations of 1,25(OH)2D3.Incubated for 48 h,cell proliferation of osteoblast were examined by MTT reduction assay (mono-nuclear cell direc cytotoxicity assay),the osteocalcin (OC) levels in cell medium were detected by ELISA,and the expression of VDR mRNA and protein were examined by using SYBR Green real-time PCR and Western blot,respectively.Results 1.After incubation with 1,25(OH)2D3 for 48 h,the number of MC3T3E1 osteoblast was significantly less than that in control group(P0.05).3.SYBR Green real-time PCR and Western blot results showed that the expression of VDR mRNA as well as VDR protein of osteoblast in 10-8,10-9 mol/L experimental groups were significantly higher than those in control group (Pa0.05).Conclusions Cell proliferation of mouse osteoblast can be inhibited,while the cell differentiation was promoted by 1,25(OH)2D3.1,25(OH)2D3 up-regulated the expression of VDR in mouse osteoblast,which suggested that the VDR signal pathway may play some role in proliferation and differentiation of osteoblast.

[Objective]To evaluate the practicality of non-mydriatic digital fundus camera in the remote screen of diabetic retinopathy for community residents.[Methods]Ninety-two patients(184 eyes)with type 2 diabetes mellitus have been taken 1-field and 5-field non-mydriatic fundus photography and examination in mydriatic fundus by pre-placed-mirror ophthalmoscopy by a ophthalmologist,the results were sent to the hospital with a computer programs. A specialist evaluates the consistency of detectable rate of diabetic retinophathy(DR)among the 3 methods.The time of tak-ing 1-field and 5-field non-mydriatic fundus photography is compared.[Results]All the three methods show good consis-tency in detectable rate of DR compare with each other,the κ value is 0.89 for 1-field non-mydriatic fundus photography and examination in mydriatic fundus by preplaced-mirror ophthalmoscopy,0.95 for 1-field and 5-field non-mydriatic fundus photography and 0.95 for 5-field non-mydriatic fundus photography and examination in mydriatic fundus by pre-placed-mirror ophthalmoscopy,respectively. The 1-field non-mydriatic fundus photography spent less time compares with 5-field non-mydriatic fundus photography(55.4±5.8 vs 405.9±68.5 s,P<0.01).[Conclusion]The remote screen for diabetic retinopathy in community based on non-mydriatic digital fundus camera is worth promoting,we suggest 1-field non-mydriatic fundus photography as a screen method.