Objective:To study the role of cadherin 1 (CDH1) gene DNA methylation in autoimmune thyroiditis (AIT) in population from different water-iodine regions.Methods:From May to June 2019, the information of AIT cases and healthy individuals in Shandong Province were collected in three types of water-iodine regions: iodine-fortification (IF) region, iodine-adequate (IA) region and iodine-excess (IE) region. A case-control study design was applied to match 176 AIT cases (case group) with age, gender, body mass index, and place of residence in a 1 ∶ 1 ratio to 176 healthy individuals (control group). Fasting urine and whole blood samples were collected to test the contents of urinary iodine, thyroid function indicators [serum free triiodothyronine (FT 3), free thyroxine (FT 4), thyroid stimulating hormone (TSH)], and serum iodine. The DNA methylation levels of the target region of the CDH1 gene and its four CpG sites in whole blood were determined using methylation sequencing technology for target regions (MethylTarget TM). Results:The DNA methylation level of the target region of CDH1 gene in the case group was 0.832 ± 0.044, and that in the control group was 0.828 ± 0.049, there was no statistically significant difference between the two groups ( t = 0.76, P = 0.448). There was no statistically significant difference in DNA methylation levels of the four CpG sites in the target region of CDH1 gene between the case group and the control group ( P > 0.05). There was no statistically significant difference in the DNA methylation level of the CDH1 gene target region between the case group and the control group in IF, IA and IE regions ( P > 0.05). The detection results of DNA methylation levels at CpG sites in the target region of CDH1 gene in different water iodine regions showed that the DNA methylation level at site 83 in case group in IF region was higher than that in the control group ( t = 2.30, P = 0.023). However, there was no statistically significant difference in the DNA methylation levels of the four CpG sites between the case group and the control group in IA and IE regions ( P > 0.05). The DNA methylation level of CDH1 gene target region in AIT patients was not significantly correlated with urinary iodine, serum iodine, and serum FT 3, FT 4, and TSH contents ( P > 0.05), but was significantly negatively correlated with age ( r =-0.19, P = 0.014). Conclusions:The DNA methylation level at CpG site 83 of CDH1 gene in AIT patients in IF region is significantly higher than that in control population, indicating that DNA methylation at this locus may be involved in the occurrence and development of AIT after iodine fortification. The DNA methylation level of CDH1 gene is negatively correlated with age.

Objective:To study the role of cadherin 1 (CDH1) gene DNA methylation in autoimmune thyroiditis (AIT) in population from different water-iodine regions.Methods:From May to June 2019, the information of AIT cases and healthy individuals in Shandong Province were collected in three types of water-iodine regions: iodine-fortification (IF) region, iodine-adequate (IA) region and iodine-excess (IE) region. A case-control study design was applied to match 176 AIT cases (case group) with age, gender, body mass index, and place of residence in a 1 ∶ 1 ratio to 176 healthy individuals (control group). Fasting urine and whole blood samples were collected to test the contents of urinary iodine, thyroid function indicators [serum free triiodothyronine (FT 3), free thyroxine (FT 4), thyroid stimulating hormone (TSH)], and serum iodine. The DNA methylation levels of the target region of the CDH1 gene and its four CpG sites in whole blood were determined using methylation sequencing technology for target regions (MethylTarget TM). Results:The DNA methylation level of the target region of CDH1 gene in the case group was 0.832 ± 0.044, and that in the control group was 0.828 ± 0.049, there was no statistically significant difference between the two groups ( t = 0.76, P = 0.448). There was no statistically significant difference in DNA methylation levels of the four CpG sites in the target region of CDH1 gene between the case group and the control group ( P > 0.05). There was no statistically significant difference in the DNA methylation level of the CDH1 gene target region between the case group and the control group in IF, IA and IE regions ( P > 0.05). The detection results of DNA methylation levels at CpG sites in the target region of CDH1 gene in different water iodine regions showed that the DNA methylation level at site 83 in case group in IF region was higher than that in the control group ( t = 2.30, P = 0.023). However, there was no statistically significant difference in the DNA methylation levels of the four CpG sites between the case group and the control group in IA and IE regions ( P > 0.05). The DNA methylation level of CDH1 gene target region in AIT patients was not significantly correlated with urinary iodine, serum iodine, and serum FT 3, FT 4, and TSH contents ( P > 0.05), but was significantly negatively correlated with age ( r =-0.19, P = 0.014). Conclusions:The DNA methylation level at CpG site 83 of CDH1 gene in AIT patients in IF region is significantly higher than that in control population, indicating that DNA methylation at this locus may be involved in the occurrence and development of AIT after iodine fortification. The DNA methylation level of CDH1 gene is negatively correlated with age.

Objective To investigate the epidemic factors of human brucellosis in Qiqihar from 2008 to 2014 so as to provide a scientific basis for prevention and control of the disease.Methods Descriptive epidemiologic method was used to analyze the monitoring results of human brucellosis in Qiqihar between 2008 and 2014.Indexes observed were:the incidence rate,the distribution of gender,age,occupation,area and time.Results From 2008 to 2014,there were a total of 15 003 cases of brucellosis covering all counties.The average incidence rate was 38.85/100 000.The average incidence rate of Meilisi Daur District was the highest,178.93/100 000.Cases occurred year around and peaked in March-July.The average incidence rate of male and female brucellosis was 57.53/100 000 and 19.35/100 000,respectively,and male patients were more than female (x2 =3 658.973,P ＜ 0.05).Most patients were in the 41-50 years old age group,and the number of patients was 4 386.The major occupation was farmer (herdsmen),which acount for 93.96％ (14 097/15 003).Conclusions Qiqihar is the epidemic area of brucellosis and has a higher incidence.Governments should pay nore attention to the epidemic of brucellosis.Health education and intervention measure for high-risk population should be strengthened and the professional team should be reinforced so as to reduce the incidence of brucellosis.

Objective To investigate the knowledge awareness on hepatitis B prevention among voluntary blood donor in Qiqihar, and analyze its influencing factors to provide a evidence for implementation of effective health education. Methods A total of 1 026 voluntary blood donors were investigated by self-design questionnaire in Blood Donor Room in Qiqihar in June 2014, and the data was analyzed by SPSS 13. 0. Results The knowledge awareness of 1 026 donors was 55. 9%, in which the illiterate had the lowest rate of knowledge awareness (24. 0%), and junior college and beyond educational background having highest rate (73. 3%). There were no statistical differences of hepatitis B prevention knowledge awareness between different age groups (P>0. 05);but donors with different culture had statistical differences on the hepatitis B prevention knowledge awareness, and the method and expected method to acquire the knowledge (P<0. 01); the donors with different culture also had different attitudes towards the HBV infect-or (χ2 =94. 17,P<0. 01). Conclusions The voluntary blood donors have low awareness of hepatitis B prevention knowledge in Qiqihar, have the fear and discrimination for HBV infect-or, so we should provide different health education method according to different group characteristics.

Objective To enhance the level and ability of measuring pesticide residues in raw milk and find out the primary factors of affecting measurement uncertainty.Methods The mathematic model of measurement was established in order to evaluate measurement uncertainty of organophosphorus pesticide residues in raw milk with gas chromatography.Results The standard measurement uncertainty of organophosphorus pesticide residues in raw milk made up of weighing,sampling and diluting procedures,standard matter,sample volume,instrument calibration.The calculating formula of expanded measurement uncertainty was U=k?CX?urel(tptal).The expression of measurement result was C=CX?U.Volume of 6 kinds of organophosphorus pesticides residues were 0.4?0.050,0.4?0.029,0.4?0.027,0.4?0.029,0.4?0.057,0.4?0.034(mg/kg) respectively in raw milk which the standard matter of pesticide was added in.Conclusion From the evaluation of measurement uncertainty of pesticide residues in raw milk with gas chromatography,we can see that the measurement uncertainty is composed of many factors,which commonly comes from random variable and fuzzification,and can be assessed by statistic distribution and standard deviation.