Objective To investigate the status of coal-burning type endemic fluorosis in Ludian County of Yunnan Province,to evaluate the prevention and control effect.Methods Multi-stage sampling was adopted in 2016.Five townships from Ludian endemic fluorosis areas and 2 villages of each township were randomly selected.The condition (children's dental fluorosis,urinary fluoride,adult skeletal fluorosis),epidemic factors (use of stoves,fluoride content of main household foods,indoor air fluoride content),health education awareness of endemic fluorosis were investigated in the above mentioned villages.Results The dental fluorosis positive rate of children aged 8-12 was 10.14％ (51/503) while a total of 503 children were investigated,the index of dental fluorosis was 0.16,and adult skeletal fluorosis detection rate was 1.92％ (2/104) while a total of 104 adults were investigated.The geometric mean of urinary fluoride content of children was 0.39 mg/L,ranging from 0.02 to 2.54 mg/L.Totally 98,161,and 151 samples of pepper,rice,and corn were detected.The medians of fluoride content were 0.96,0.42,and 0.43 mg/kg,respectively,ranging from 0.26 to 13.46,0.13 to 2.20,and 0.21 to 2.54 mg/kg,respectively,in which the fluorine contents of pepper 48.98％ (48/98) was higher than 1.0 mg/kg.The correct drying rates of both corn and pepper were 100.00％ (201/201),and the correct preservation rates of corn and pepper was 99.50％ (200/201) and 100.00％ (201/201),respectively.The use rate of improved stove,rate of intact stove,correct use rate of intact stove were 100.00％ (201/201),96.02％ (193/201) and 100.00％ (193/193),respectively.The fluoride contents in the indoor air of the families (the fire period was 0.32 μg/m3 and the fire extinguishing period was 1.22 μg/m3) from the areas of fluorosis which had properly used the improved stoves were lower than that of the national hygienic limit content (the one-hour average concentration limit is 20 μg/m3).The knowledge of prevention and control of coal-burning type fluorosis among fifth-grade primary school students and household heads was investigated in 104 and 201 people,respectively,with the awareness rates of 80.77％ (252/312) and 86.23％ (520/603),respectively.Conclusion By implementing the comprehensive prevention and control measures,which mainly focus on the improvement of the stove and the health education,the coal-burning fluorosis in Ludian County has been effectively controlled,and the prevention and control work has achieved remarkable results.

Objective After implementation of new standard iodized salt,to comprehensively assess the iodine nutrition levels of different populations in Dali City of Yunnan Province.Methods From 2012 to 2015,in Dali City,there were 5 districts divided into east,west,south,north and middle,each district selected 1 township (town),and each township (town) selected 4 administrative villages,15 households for edible salt in each administrative village were sampled,and the salt iodine content was measured by "General Test Method in Salt Industry Determination of Iodine" (GB/T 13025.7-2012).In 2014,in the five districts of east,west,south,north and middle of Dali City,one township (town) was selected,and 20 pregnant women in the early,middle and late stages,respectively,20 lactating women,20 ordinary healthy adults and 20 children aged 0 to 4 were selected from each township (town);one primary school in each township (town) was selected in each district,and 40 students aged 8-10 years old were selected from each primary school as the survey objects.The urine samples of the survey objects were collected,and the urinary iodine content was measured by "Method for Determination of Iodine in Urine by As3+-Ce4+ Catalytic Spectrophotometry" (WS/T 107-2006).In 2015,in each administrative village of Dali,a water source with the largest number of drinking people was investigated,and water iodine was detected by the "Method of Water Iodine Detection Suitable for Iodine Deficiency and High Iodine Areas".Through questionnaires,the sources of iodine supplementation for pregnant and lactating women were investigated.Results The qualified iodized salt consumption rate of residents was higher than 90％ per year from 2012 to 2015,and median of salt iodine decreased from 29.38 mg/kg (2012) to 24.96 mg/kg (2015).The medians of urinary iodine in different populations were 136.85 μg/L for pregnant women (n =356),102.63 μg/L for lactating women (n =111),164.03 μg/L for adults (n =163),209.61 μg/L for 8-10 years old children (n =200),157.27 μg/L for children aged 0-＜ 2 years old (n =57),and 134.08 μg/L for 2-4 years old children (n =50).The median of iodine content of drinking water (n =142) in Dali was 0.62 μg/L,the range of iodine content was 0.00-9.92 μg/L.The average intake frequencies of iodine-rich seaweed for pregment women and lacting women were 0.99,1.07 time/month,respectively,only 1.99％ (9/453) of the population supplemented iodine through multivitamin and minerals tablets.Conclusions After reduction of salt iodine content,the iodine nutrition of populations in Dali City (a low water iodine region) is generally at an appropriate level.Maintaining a higher level of qualified iodized salt consumption rate,strengthening the monitoring of different populations and promotion of healthy behaviors are key steps in prevention and control of the disease in the future.

Objective To study the urinary iodine and serum thyroid stimulating hormone (TSH) and thyroglobulin (Tg) levels in adult women (pregnant women, lactating women, childbearing age women) in Dali City, Yunnan Province, and to explore the feasibility of TSH and Tg as indicators for iodine nutrition evaluation in pregnant women. Methods From July to December 2014, from the five districts of east, west, south, north and middle district of Dali City, Yunnan Province, one township ( town ) was selected , and 20 pregnant women in the early, middle and late stages, respectively, 20 lactating women, 20 childbearing age women were selected from each township ( town ) , collected urine and blood samples , and urinary iodine , serum TSH and Tg levels were detected. Results The medians urinary iodine (MUI) in different populations were 136.85μg/L for pregnant women (n = 356 ) , 102 . 63 μg/L for lactating women ( n = 111 ) , 166 . 21 μg/L for childbearing age women ( n = 98 ) . The medians TSH in pregnant women (n = 368), lactating women (n = 112) and childbearing age women (n = 96) were 1.995, 2.345 and 2.565 mU/L, respectively, the difference between the different populations was statistically significant(χ2=16.128, P<0.05). The medians Tg of pregnant women, lactating women and childbearing age women were 10.49, 9.28 and 9.66μg/L, respectively, the difference between the three groups was not statistically significant (χ2 = 2.083, P > 0.05). A total of 120, 126, and 122 cases of pregnant women in the early, middle, and late stages were investigated. The medians TSH of early, middle and late pregnancy were 1.850, 2.030 and 2.235 mU/L, respectively, the difference between the different stages of pregnancy was statistically significant (χ2 = 6.970, P <0.05). The medians Tg of early, middle and late stages were 10.56, 10.78 and 10.08 μg/L, respectively, the difference between the different stages of pregnancy was not statistically significant (χ2= 1.058, P > 0.05). Conclusions Tg levels are stable in the different stages of pregnancy women and it can be considered as an indicator of iodine nutrition evaluation in pregnant women.

Objective To understand the situation of iodine deficiency disorders and iodine nutrition of children in Yunnan Province after the implementation of new standard of salt iodine,and provide the basic data for prevention and control of iodine deficiency disorders.Methods Using multistage sampling method,Yunnan provincial evaluations for iodine deficiency disorders elimination were carried out.According to the comparative analysis of 2010 (pre-adjustment) and 2015 (post-adjustment) evaluation results,the changes of the median of salt iodine,the coverage rate of iodized salt,the qualified rate of iodized salt,the rate of qualified iodized salt consumption,goiter rate of school children aged 8-10 and the median of urinary iodine were evaluated.Salt iodine was tested using the "Salt Industry General Test Method for Determination of Iodine" (GB/T 13025.7-1999);thyroid volume examination of children using B-scan ultrasonography,thyroid volume calculation and enlargement judgment using "Diagnostic Criteria for Endemic Goiter" (WS 276-2007);and urinary iodine detection using "Urinary Iodine Arsenic Cerium Catalytic Spectrophotometry" (WS/T 107-2006).Results The medians of salt iodine in 2010 and 2015 were 30.6 and 22.4 mg/kg,respectively,the difference was statistically significant (U =317 503.50,P ＜ 0.01).The coverage rates of iodized salt in 2010 and 2015 were 99.6％ (1 681/1 688) and 98.9％ (2 592/2 622),the qualified rates of iodized salt were 98.6％ (1 657/1 681) and 89.7％ (2 325/2 592),and the rates of qualified iodized salt consumption were 98.2％ (1 657/1 688) and 88.7％ (2 325/2 622),and the differences were statistically significant (x2 =6.42,125.11,130.18,P ＜ 0.01);the rates of children goiter in 2010 and 2015 were 0.8％ (25/3 272) and 1.4％(44/3 245),respectively;the medians of urinary iodine of children were 289.0 and 157.3 μg/L,respectively,the difference was statistically significant (U =1 121 669.50,P ＜ 0.01).Conclusion After decreasing of salt iodine level starting from 2012 in Yunnan Province,the children iodine nutrition condition is in a more proper level.

Objective To optimize the extraction process of main iridoid glycosides in Damnacanthus officinarum Huang and evaluate the antioxidant activity of Damnacanthus officinarum Huang in vitro. Methods The classical heating-reflux extraction method was selected. The volume fraction of ethanol, the volume of solvent and extraction time were taken as the evaluation factors. The comprehensive score of extraction yield and the monotropein content were used as the evaluation indexes. An orthogonal test was designed to select the best extraction conditions. The total reducing capacity, DPPH clearance rate and hydroxyl radical scavenging rate were measured to determine its antioxidant activity in vitro. Results The optimal extraction process was the reflux with 6 times volume of 60% ethanol for 2 hours. Damnacanthus officinarum Huang has certain antioxidant capacity, and the activity of ethyl acetate part had the best effect. Conclusion The optimized extraction process is stable and feasible, which can be used for extraction of the iridoid glycosides from Damnacanthus officinarum Huang. This study has proved that Damnacanthus officinarum Huang has certain antioxidant activity.