Aim To study the effect of silymarin on proliferation and apoptosis of human osteosarcoma saos-2 cells and to explore its possible mechanisms .Meth-ods Control group and different concentration groups of silymarin were set , and Saos-2 cells were treated with silymarin .Celluar morphologic changes were ob-served by inverted phase contrast microscope .Prolifer-ation of cells was tested CCK-8 assay .Apoptosis rate of cells was analyzed by flow cytometry . ERK1/2、p-ERK1/2 and cleaved caspase-3 protein expression were measured by Western blot .Results Silymarin inhibi-ted the proliferation of Saos-2 cells in a time-dependent and concentration-dependent manner . Silymarin in-duced the apoptosis of Saos-2 cells in a concentration-dependent manner . Silymarin decreased p-ERK1/2 protein expression and increased cleaved caspase-3 protein expression in a concentration-dependent man-ner, while ERK1/2 protein expression had no obvious change.Conculsions Silymarin can inhibit the prolif-eration of human osteosarcoma saos-2 cells and induce apoptosis of them , and the mechanism may be related to inhibition of ERK signaling pathway and upregulated caspase-3 protein expression .

Aim To study the role of the total flavonoids from arachniodes exilis(TFAE) in osteogenic differentiation of human umbilical cord mesenchymal stem cells(hUCMSCs).Methods hUCMSCs were isolated and cultured by tissue explants adherent method, hUCMSCs at passage 3 were used to do the experiment, hUCMSCs were treated by different concentrations of TFAE, and cellular viability was measured by CCK 8 assay;alkaline phosphatase(ALP) activity was tested by AMP method;calcium nodule formation was detected by alizarin red staining;expression level of osteogenesis-related gene type I collagen enzyme a1(collagen type Ia1, Col1a1), osteopontin(OPN), Runx2, Osterix(Osx) mRNA was measured by RT-PCR;expression level of Col1a1,OPN protein was measured by Western blot.Results Certain concentration of TFAE(1 mg·L-1, 5 mg·L-1) promoted cellular proliferation, calcium nodules were more, ALP activity was enhanced;expression level of osteogenesis-related gene Col1a1, OPN, Runx2, OsxmRNA and Col1a1, OPN protein was up-regulated.Conculsion A certain concentration of TFAE promotes proliferation and osteogenic differentiation of hUCMSCs.

Family physicians on contract for rural families play an important role in primary medical and health services. This research raises for the first time the practical function and position of rural family physicians on contract. On this basis, a theoretical competency model of rural family physicians was constructed by referring to McClelland′s competency dictionary, relevant policy documents in China and literatures at hand. The model included six level-1 dimension indicators: achievement, management, service, cognition, influence, and self-efficacy, as well as 17 level-2 dimension indicators. At the same time, the paper explained in detail these indicators and compared them with the international indicators of family physicians, highlighting the working characteristics and practical needs of family physicians on contract in rural China.

ObjectiveTo investigate chlorate contamination level in infant formula sold in Shanghai， and to evaluate the dietary exposure risk to infants in Shanghai. MethodsWith the risk monitoring data of chlorate in infant formula sold in Shanghai in 2020， combined with the dietary consumption data of infants， the dietary exposure of chlorate in infant formula was assessed via the point assessment method. ResultsIn 2020， the overall detection rate of chlorate in 120 infant formula samples was 98.3% （118/120）， the mean content was 124.5 μg⋅kg^-1， the 50 percentile value was 64.6 μg⋅kg^-1， and the maximum value was 1 475.0 μg⋅kg^-1. The mean and 95 percentile value of daily chlorate intake from infant formula for infants aged 0‒36 months in Shanghai were 1.10 and 1.84 μg⋅kg^-1， accounting for 36.7% and 61.3% of the tolerable daily intake （TDI） of chlorate （3μg⋅kg^-1）， respectively. The mean， 50 percentile value and 95 percentile value of daily chlorate exposure of infants in different month-age groups （0‒6 months， 6‒12 months， 12‒36 months） through infant formula were lower than the TDI value. ConclusionThe health risk of daily chlorate intake from infant formula for infants and young children aged 0‒36 months in Shanghai is at an acceptable level.