Objective:To understand the contents of edible salt iodine and urinary iodine of children and pregnant women in Yunnan Province, and to evaluate the iodine nutrition status, so as to provide a basis for scientific prevention and treatment of iodine deficiency disorders (IDD).Methods:From November to December 2020, one county (city) was selected from each prefecture (city), two townships (towns and streets) were selected from each county (city) and two villages (neighborhood committees) were selected from each township (town and street) from each of the 16 prefectures (cities) in Yunnan Province as the investigation sites. A total of 20 non-boarding children (male and female balanced) aged 8 - 10 years old were selected from each primary school in each village (neighborhood committee) to collect salt and urine samples. A total of 80 children were investigated in each county (city). A total of 20 pregnant women were selected from each township (town and street) to collect salt and urine samples. A total of 40 pregnant women were investigated in each county (city). All salt samples and urine samples were tested for iodine contents.Results:A total of 2 009 salt samples and 2 041 urine samples (1 375 for children, 666 for pregnant women) were collected from children aged 8 - 10 years old and pregnant women in 16 counties (cities) of Yunnan Province. Among them, the median salt iodine was 26.0 mg/kg, the coverage rate of iodized salt was 100.0% (2 009/2 009), the qualified rate of iodized salt was 98.7% (1 982/2 009), and the consumption rate of qualified iodized salt was 98.7% (1 982/2 009). The difference of salt iodine content in key populations in different counties (cities) was statistically significant ( H = 258.98, P < 0.01). The median urinary iodine of children aged 8 - 10 years old was 188.5 μg/L. There was statistically significant difference in urinary iodine content among children of different ages ( H = 29.45, P < 0.01), but there was no statistically significant difference in urinary iodine content among children of different genders ( H = 1.43, P > 0.05). In addition, the median urinary iodine of pregnant women was 141.9 μg/L, 52.1% (347/666) was < 150 μg/L. There was statistically significant difference in urinary iodine content of pregnant women in different counties (cities, H = 88.32, P < 0.01). Conclusions:The qualified rate of iodized salt, the coverage rate of iodized salt and the consumption rate of qualified iodized salt in key populations of Yunnan Province are more than 90%, and the iodized salt supply is good. Iodine nutrition of children aged 8 - 10 years old is at an appropriate level (100 - 199 μg/L); iodine nutrition of pregnant women is in an state of iodine deficiency ( < 150 μg/L). It is suggested to strengthen IDD monitoring and health education among key populations, improve residents' awareness of disease prevention, and make scientific iodine supplementation.

ObjectiveTo investigate effect of astragaloside Ⅳ on the proliferation， migration， and invasion of colorectal cancer HCT116 cells and the underlying molecular mechanism. MethodColorectal cancer HCT116 cells were classified into blank group （DMSO） and low-dose （15.7 mg·L^-1）， medium-dose （31.4 mg·L^-1）， and high-dose （62.8 mg·L^-1） astragaloside Ⅳ groups. After drug treatment， the morphological changes of HCT116 cells were observed under an inverted microscope. Cell viability was detected by cell counting kit-8 （CCK-8） assay， and the migration and invasion of cells were detected based on scratch assay and Transwell assay. The expression of cyclin-dependent kinase inhibitor （p21）， CyclinD₁， B-cell lymphoma-2 （Bcl-2）， and Bcl-2-associated X protein （Bax） in the cells was examined by Western blot. ResultCompared with the blank group， cells in the three astragaloside Ⅳ groups demonstrated slow growth， low density， inconsistent morphology， nuclear shrinkage， degradation of cytoplasm， and high death rate. Moreover， cell viability decreased in a concentration-dependent manner in the astragaloside Ⅳ groups. Cell migration and invasion were inhibited （P<0.05， P<0.01）， and the inhibition rate was in positive correlation with the concentration of the astragaloside Ⅳ. The expression of pro-apoptotic protein Bax in low-dose， medium-dose and high-dose astragaloside Ⅳ groups increased gradually in a concentration-dependent manner， while the expression of p21， CyclinD₁ and anti-apoptotic protein Bcl-2 decreased gradually in a concentration-dependent manner compared with those in the blank group （P<0.05， P<0.01）. ConclusionAstragaloside Ⅳ can suppress the proliferation， migration， and invasion of colorectal cancer HCT116 cells and promote the apoptosis， thus inhibiting the occurrence and development of colorectal cancer.