Detecting resorcinol in workplace air by gas chromatography with capillary column / 中国职业医学

OBJECTIVE: To establish a method for detecting resorcinol in workplace air by gas chromatography with capillary column. METHODS: The resorcinol in workplace air was collected into muiti-hole absorbing tubes with distilled water and detected by capillary chromatographic column by direct injection. RESULTS: The good linear range of resorcinol was 1.7-200.0 mg/L. The correlation coefficient was 0.999 9. The detection limit was 0.5 mg/L and the lower limit of quantitation was 1.7 mg/L. The minimum detection concentration was 0.7 mg/m~3(sample volume was 7.5 L). The standard recovery rate was 98.5%-102.6%. The within-run relative standard deviation(RSD) was 0.7%-3.6% and the between-run RSD was 1.8%-5.7%. CONCLUSION: This method has high sensitivity, accuracy and can effectively remove interference, which is suitable for determination of resorcinol in workplace air.

The protective mechanisms of MEK1/2 inhibitor PD98059 on ox-LDL induced injury of HUVEC and the influence on the expression of LOX-1 / 重庆医学

Objective To investigate the protective mechanism of MEK1/2 inhibitor PD98059 on ox-LDL induced injury of human umbilical vein endothelial cells (HUVEC),and its influence on the expression of LOX-1.Methods HUVEC damage models were established by using ox-LDL and were treated with PD98059 later,divided into the negative control group,the ox-LDL group,the positive control group and the PD98059+ox-LDL group.The effect of inhibition of MEK1/2 on ox-LDL induced HUVEC damage was measured.Results Compared with the negative control group,the levels in the ox-LDL group of LOX-1,pMEK1/2,RhoA,ROCK1,ROCK2,TNF-α and IL-6 were increased significantly,the proliferations of HUVEC and the productions of NO were decreased (P＜0.05).Compared with the ox-LDL group,the levels in the positive control group and the PD98059+ox-LDL group of pMEK1/2,RhoA,ROCK1,ROCK2,TNF-α and IL-6 were decreased,the proliferation of HUVEC and the production of NO were increased (P＜0.05).Conclusion PD98059 inhibit the MEK1/2 signaling pathway to suppress the ox-LDL induced damage of HUVEC by decreasing the expression of LOX-1.

Analysis of monitoring results of drinking-water fluorosis in Jiangsu Province from 2011 to 2015 / 中华地方病学杂志

Objective To understand the drinking water type fluorosis in Jiangsu Province, dynamically monitor the disease trends, and to evaluate the operation effect of the water project comprehensively. Methods Twenty-six fluorosis districts and counties in Xuzhou, Lianyungang, Suqian, Huaian and Yancheng were selected as the monitoring sites. The change of water improvement engineering and the value of water fluoride were surveyed and tested. There were three different situations of changed water: the water improvement engineering operated normally was the first, the water improvement engineering operated abnormally or water fluorine excesses the standard was the second,and without water improvement was the last.The teeth of children aged 8 to 12 years were checked according to the method of Dean. The skeletal fluorosis of adults was checked according to "Diagnostic Criteria of Endemic Skeletal Fluorosis"(WS 192-2008) by X-ray inspection. Results The normal operation rates of changed water project from 2011 to 2015 were 100.00% (30/30), 85.29% (29/34), 82.50% (33/40), 95.92% (47/49),and 97.83%(45/46),and the excessive rates of water fluorosis for normal operating engineering were 13.33%(4/30),17.24%(5/29),9.09%(3/33),14.89%(7/47),and 11.11%(5/45).The dental fluorosis detection rates of children aged 8 to 12 years were 33.68% (194/576), 28.30% (711/2 512), 36.25% (1 577/4 350), 22.06% (837/3 794), and 20.44% (903/4 417) from 2011 to 2015, the differences were statistically significant (χ2= 190.952, P < 0.05). The dental fluorosis detection rates in the three situations of water changed annually was statistically significant (χ2=129.336, 130.402, 21.419, P < 0.05). The detection rates between three different water conditions were 21.88% (2 857/13 057), 57.23% (1 156/2 020), 36.54%(209/572), and the differences were statistically significant (χ2=206.295, P < 0.05). Differences between the villages with water improvement engineering changed but not worked and the villages with water improvement engineering changed and worked well and the villages without the water improvement engineering were statistically significant(χ2=200.861,36.336,P<0.0125).The difference of detection rates between the villages with normal operation and the villages without water improvement was not statistically significant(χ2=2.131, P>0.0125).The X-ray detection rates of skeletal fluorosis in adults from 2011-2015 were 17.83% (51/286), 16.61% (49/295), 15.36% (51/332), 10.95% (53/484), and 5.16% (16/310); urinary fluoride range was 0.02 - 22.0 mg/L; the geometric average was 0.67 - 4.06 mg/L, there was no statistical significant difference of skeletal fluorosis distribution annually(χ2=6.060, P > 0.05). Conclusion The general condition of drinking water type fluorosis in Jiangsu Province from 2011 to 2015 is gradually under control, but the engineering operation and water quality improvement still need to be improved; water change project not functioning or with excess fluorine is more harmful to children's teeth.

Analysis of surveillance results on iodine deficiency disorders in Jiangsu Province in 2014 / 中华地方病学杂志

Objective To investigate the current status of iodine deficiency disorders (IDD) in Jiangsu Province and to evaluate the effects of preventive and control measures on IDD in Jiangsu Province in 2014.Methods With the use of probability proportional to size sampling method (PPS),30 counties (cities,districts)in Jiangsu Province were selected.Only 1 primary school was selected in each county (city,district) and 50 students of 8-10 years old (halt male and half female,uniformly distributed in age groups) were selected in each school.Goiter,salt iodine,urinary iodine,height and weight were examined.Thirty students from Grade 5 in each school were selected at random,and health education questionnaire survey was conducted.In the area where the primary school located,5 housewives were selected and a questionnaire survey was conducted.Two-5 drinking water samples from the village where the primary school located were collected and the water iodine concentration was tested.Urine samples and salt samples from 20 pregnant women and 10 lactating women in the village where the primary school located were collected,and urinary iodine and salt iodine were detected.Thyroid volume was measured by palpation method and ultrasound.Urinary iodine was detected by arsenic cerium catalytic spectrophotometry (WS/T 107-2006).The iodine level in salt was determined by direct titration;the salt samples from Sichuan and other enhanced salt were detected by arbitration (GB/T 13025.7-1999).Water iodine was tested using the method suitable for iodine deficiency and high iodine areas (recommended method of reference laboratory of national iodine deficiency disorders).Results A total of 1 524 children aged 8-10 years old were examined.Forty-two children had goiter by palpation method and the goiter rate was 2.76％ (42/1 524).Forty-one children had goiter by ultrasound and the goiter rate was 2.69％ (41/1 524).Totally 1 523 urine samples of children aged 8-10 years old were tested and the median of urinary iodine was 208.03 μg/L.A total of 1 524 salt samples were tested,the coverage rate of iodized salt was 97.44％ (1 485/1 524) and the qualified rate of iodized salt was 96.43％(1 432/1 485).The consumption rate of qualified iodized salt was 93.96％(1 432/1 524) and the consumption rate of non-iodized salt was 2.56％(39/1 524).The rates of knowledge awareness about IDD among students and housewives were 81.36％ (2 287/2 811)and 91.18％ (424/465),respectively.Sixty drinking water samples were collected and the median of water iodine was 16.83 μg/L.Six hundred urine samples of pregnant women and 304 urine samples of lactating women were tested.The median of urinary iodine was 155.16 and 138.33 μg/L,respectively.Conclusions After achieving the goal of eliminating IDD,the control effect in Jiangsu Province is sustainable.The crowd's risk of iodine deficiency has declined significantly.

Analysis of iodine nutrition in residents of coastal and inland areas of Jiangsu Province / 中华地方病学杂志

Objective To master iodine intake ways of children in Yancheng (coastal) and Zhenjiang (inland) cities,analyze their urinary iodine difference and provide solid evidence for adjustment of salt iodine and adequate iodine intake level of local residents.Methods Totally 50％ counties were randomly selected in Yancheng and Zhenjiang cities and 5 towns were sampled in each county in 2014,local water iodine,domestic salt iodine,local eating habits and urine iodine of children 8-10 years old were investigated,and the influences of different iodine intake ways on urine iodine level were analyzed.Results The median of water iodine was 4.76 μg/Lin Zhenjiang (n =40) and 50.80 μg/L in Yancheng (n =50),the difference was statisticelly significant in two cities (Z =6.93,P ＜ 0.05).Totally 2 400 salt samples were tested,the mean of salt iodine was (24.20 ± 5.07) mg/kg in Yancheng (n =1 500) and (22.87 ± 2.77) mg/kg in Zhenjiang (n =900),the difference was statisticelly significant in two cityies (t =7.23,P ＜ 0.05).The salt intake level in Zhenjiang (10.69-± 9.00) g/d appeared to be higher than that in Yancheng (8.40 ± 3.57) g/d,but the difference was not statistically significant (t =1.62,P ＞ 0.05).Totally 1 200urine samples were tested,the urine iodine level of Zhenjiang got higher results (265.83 μg/L,n =450) than that of Yancheng (182.15 μg/L,n =750,Z =12.18,P ＜ 0.05).The ratio of water iodine intake/salt iodine intake was about 1 ∶ 4 in Yancheng and 1 ∶ 50 in Zhenjiang,while residents in Zhenjiang got 21％ of daily iodine through extra ways.Eating habits like eating out did not have significant impact on urine iodine.Conclusions Based on the water iodine level,Yancheng is considered to be a appropriate iodine level area while Zhenjiang is a lack region.However,Zhenjiang has a higher urine iodine level than Yancheng,which is more than adequate to the recommendation.Salt iodine is a main iodine source in both cities.In iodine appropriate and deficiency areas,eating habits and food choices may play a more important role than geochemical factors in iodine intakes among residents.

A survey of iodine nutritional status of the crowd in iodine-deficient areas that did not participate in the provincial surveillance program on iodine deficiency disorders in Jiangsu Province / 中华地方病学杂志

Objective To investigate the iodine nutritional status of the crowd that did not participate in the iodine deficiency disorders (IDD) survey in iodine deficiency areas in Jiangsu Province so as to provide a basis for prevention and control of IDD.Methods Eight to ten years old children were chosen from the counties(cities,districts) of Jiangsu Province that did not participate in the IDD survey and urine samples of students and salt samples of their families were researched.In each county (city,district) one township (street) was selected according to 5 directions of east,south,west,north,center; in each township one primary school was selected and in each primary school 20 children aged 8-10 were chosen half of the male and female,to collect their urine samples and salt samples at their families.Urinary iodine was measured using arsenic cerium catalytic spectrophotometric method (WS/T 107-2006),and salt iodine was measured using direct titration of universal test method in salt industry (GB/T 13025.7-1999).Iodine nutrition criterion of international health organization recommended staindard:children urinary iodine ＜ 100 μg/L as iodine deficiency,100-199 μg/L as iodine appropriate,200-299 μg/L as iodine more than appropriate,≥ 300 μg/L as iodine excess.Results A total of 7 523 urinary samples of 8-10 years old children were collected from 76 iodine deficiency counties (cities,districts),and the median of urinary iodine was 235.0 μg/L.In all investigated counties (cities,districts),the medians of urinary iodine of 22 counties(cities,districts) were 100-199 μg/L,42 counties(cities,districts) were 200-299 μg/L,and 12 counties (cities,districts) were ≥300 μg/L.A total of 7 523 salt samples were collected,and the median of salt iodine was 29.68 mg/kg; Taizhou City had the highest salt iodine median,which was 31.43 mg/kg; and Lianyungang City,the lowest,25.11 mg/kg.The coverage rate of iodized salt was 98.6％(7 417/7 523); iodized salt qualification rate was 98.6％ (7 312/7 417); and consuming rate of qualified iodized salt was 97.2％(7 312/7 523) in 76 iodine deficiency counties (cities,districts).Conclusions The progress in prevention and control of IDD in iodine-deficient areas that did not participate in IDD survey in the past is good in Jiangsu Province; the overall level of iodine nutrition of whole population is adequate.But the median of urinary iodine in some counties (cities,districts) is at a higher level.

Evaluation of problem-based learning from students'angle / 中国实用护理杂志

Objective To know the advantages and disadvantages of problem-based learning from students'angle. Methods Interviewed 15 students by PBL scale and face to face interview,to know their ideas about problem-based learning,and then analyzed the results. Results PBL contributed to developing problem-solving skills,self-directed learning,team collaboration and extending professional knowl-edge. But it failed to show positive effect on students'learning motivation. Conclusions PBL has two sides on the outcomes of learning. Implementing PBL appropriately could gain the optimal effects.