AIM: To study the effects of neuregulin-1β (NRG-1β) on the nervous behavioral function, cerebral infarction volume, brain water content (BWC), neuroal apoptosis and aquaporin-4 (AQP-4) expression in astrocytes after cerebral ischemic reperfusion in mice. METHODS: Intraluminal thread methods were applied to establish the middle cerebral artery occlusion reperfusion (MCAO/R) model in mice. Neuregulin-1β (2 μg/kg) was injected into the internal carotid artery for treatment. The nervous behavioral function was evaluated by Bedersons test. The cerebral infarction volume was observed with tetrazolium chloride (TTC) staining. The BWC was measured by calculating the dry-wet weight ratio. The apoptotic positive cells were counted by immunofluorescence assay. The expression of AQP-4 was determined by immunohistochemical method. RESULTS: Nervous behavioral malfunction appeared in all the mice with left middle cerebral artery occlusion (MCAO) and/or reperfusion. The infarction focus showed in the ischemic hemisphere following the injury. The BWC, the numbers of neuroal apoptotic cells and AQP-4 expression in astrocytes were higher than those in sham control group. In MCAO/R+NRG-1β treatment group, the nervous behavioral function at ischemia 24 h significantly improved, the numbers of apoptotic positive cells reduced and the infarction volume decreased significantly than those in MCAO/R group (P<0.05). The BWC and AQP-4 expression in astrocytes showed no significant difference compared with MCAO/R group (P>0.05). In the reperfusion 22 h, 46 h and 70 h groups, the five indexes mentioned above were significantly different from those in the corresponding MCAO/R groups (P<0.05). CONCLUSION: NRG-1β might reduce cerebral edema and infarction volume, and improve the nervous behavioral function via down-regulating the expression of AQP-4 in astrocytes and inhibiting the neuronal apoptosis induced by ischemia reperfusion injury.

Objective:To verify the revised method of cerium sulfate catalytic spectrophotometry for iodide index of "Standard Examination Methods for Drinking Water-Nonmetal Parameters" (GB/T 5750.5-2006).Methods:From July to September 2019, the Laboratory of Department for Endemic Disease Prevention and Control of Qinghai Institute for Disease Prevention and Control verified the revised method (determination of iodide in drinking water by cerium sulfate catalytic spectrophotometry) of cerium sulfate catalytic spectrophotometry (hereinafter referred to as original method) in "Standard Examination Methods for Drinking Water-Nonmetal Parameters" (GB/T 5750.5-2006). The revised method was verified according to the requirements of "Standard Examination Methods for Drinking Water-Water Analysis Quality Control" (GB/T 5750.3-2006), including standard curve, detection limit, precision, accuracy and actual sample determination.Results:The linear range of the revised method was 0 - 20.0 μg/L, the correlation coefficient was - 0.999 4 - 0.999 8, and the detection limit was 0.231 μg/L. The relative standard deviation ( RSD) of low, medium and high iodine water samples of 6 times detection ranged from 1.4% to 9.6%, and the recoveries of low and medium water samples ranged from 89.0% to 108.0%. The detection results of national first-class reference materials for iodine composition analysis in water were within the range of standard value ± uncertainty. There was no significant difference in the test of results of 12 tap water samples between the revised method and the original standard method ( t = - 0.075, P > 0.05). Conclusion:The revised method has a good linear relationship of standard curve, high precision and accuracy, and good reproducibility, is simple and easy to operate, and is suitable for promotion and application.

Objective To find out the distribution and status of drinking-water-borne fluorosis in Qinghai,and to provide basic data for prevention and control of the disease.Methods According to the "Action Plan of Endemic Fluorosis and Arsenic Poisoning in Qinghai (2016-2020)",10 counties were selected to carry out the epidemiological study in 2016.The operation of the improvment project was investigated.The fluoride content of water was determined with fluoride ion-selective electrode,and dental fluorosis of 8-12 years old children was diagnosed by the Deans method.Results A total of 97 villages have been investigated,and all water was improved.The range of water fluoride was 0.20-2.13 mg/L.Normal operation rate of water-improving project was 83.33％ (50/60).The pass rate of water fluorine content was 96.67％ (58/60).The prevalence rate of dental fluorosis of the children was 18.70％ (774/4 140),and it was significantly lower than national standards (30％).Conclusions Water has been improved in all of the fluorosis villages.Most of the water-improving engineering projects to control drinking-water fluorosis has played a positive role,and drinking-water-borne fluorosis is under control.

Objective:To systematically evaluate the changes of serum nitric oxide (NO) content in adult patients with Kaschin-Beck disease (KBD).Methods:Systematic retrieval was conducted on China National Knowledge Infrastructure (CNKI), WanFang Data, VIP Database, PubMed, Embase and other databases, to analyze the literatures published from the database establishment to March 31, 2019, on the changes of serum NO content of adult patients with KBD. Meta-analysis was performed using Revman 5.3 software, and mean difference ( MD) and 95% confidence interval ( CI) were calculated; sensitivity analysis was performed using fixed-effect model or random-effect model based on heterogeneity results; and publication bias was evaluated using funnel chart. Results:Totally 7 qualified literatures were included, including 358 cases in the adult KBD group and 305 cases in the control group. After the heterogeneity test, there was heterogeneity among the literatures (χ 2 = 188.07, I2 = 97%, P < 0.01), so a random-effect model was used for Meta-analysis. The NO content in the KBD group was significantly higher than that in the control group (MD = 44.29, 95% CI: 30.57 - 58.00), the difference was statistically significant ( Z = 6.33, P < 0.01). Sensitivity analysis showed that the results of this study were stable. The two sides of the funnel were basically symmetrical, suggesting that the possibility of publication bias was small. Conclusion:The serum level of NO content in adult patients with KBD is significantly increased.

Objective:To investigate the molecular mechanism of excessive iodine induced experimental autoimmune thyroiditis (EAT) in mice.Methods:Sixty female non-obese diabetic (NOD) mice were selected and divided into 5 groups according to body weight [(25 ± 3) g] via the random number table method, with 12 mice in each group: control group (group A), 10-fold high iodine group (group B), 100-fold high iodine group (group C), 1 000-fold high iodine group (group D) and 1 000-fold high iodine combined with polyinosinic acid-polycytidylic acid [Poly (I:C)] group (group E). The experiment period was 16 weeks. Mice in each group drank purified water with sodium iodine (NaI) content of 0.000, 0.005, 0.050, 0.500 and 0.500 mg/L, respectively; mice in group E were intraperitoneally injected with Poly (I:C) at week 7 and week 15, respectively. At the end of the 16th week, mice were dissected and blood samples and thyroid tissue were taken. The levels of serum thyroid function indexes [thyroid stimulating hormone (TSH), free triiodothyronine (FT 3), free thyroxine (FT 4), and thyroid peroxidase antibody (TPOAb)] were detected by enzyme-linked immunosorbent assay (ELISA); the pathological changes of thyroid tissue were observed after hematoxylin-eosin (HE) staining; differentially expressed genes in thyroid tissue were detected by RNA-sequencing (RNA-seq), and analyzed by KEGG pathway; mRNA and protein levels of p38, intercellular adhesion molecule-1 (ICAM-1) and chemokine 10 (CXCL10) in thyroid tissue were detected by real-time fluorescence quantitative PCR (qPCR) and Western blotting, respectively. Results:There were statistically significant differences in serum levels of TSH (ng/ml: 6.53 ± 0.86, 6.61 ± 0.82, 7.68 ± 0.55, 7.93 ± 0.60, 8.73 ± 1.60), FT 3 (pg/ml: 59.35 ± 10.16, 53.73 ± 10.96, 46.19 ± 8.03, 41.01 ± 8.67, 34.21 ± 11.75), FT 4 (pg/ml: 136.74 ± 10.06, 124.33 ± 14.34, 101.80 ± 6.78, 91.37 ± 6.75, 73.29 ± 17.31), and TPOAb (U/ml: 130.81 ± 24.53, 145.47 ± 28.89, 166.52 ± 41.59, 199.78 ± 42.19, 201.99 ± 44.03) among the 5 groups of mice ( F = 4.77, 4.96, 23.12, 3.68, P < 0.05). Compared with group A, the serum TSH levels of mice in groups C, D and E were higher, the levels of FT 3 and FT 4 in groups B, C, D and E were lower, and the levels of TPOAb in groups D and E were higher, and the differences were statistically significant ( P < 0.05). HE staining showed that the thyroid follicle lesion in groups D and E was serious, and the EAT phenotype appeared in both groups. The differentially expressed genes were analyzed by KEGG pathway. Compared with group A, 8 metabolic pathways related to thyroid autoimmunity and inflammation were found in groups B, C, D and E. Further analysis found that 3 genes appeared in multiple pathways, namely p38, ICAM-1 and CXCL10. There were significant differences in the mRNA levels of p38, ICAM-1 and CXCL10 in thyroid tissue of the 5 groups of mice ( F = 14.77, 12.76, 16.39, P < 0.05); compared with group A, the mRNA levels of p38 in groups B, C, D and E were higher, and the mRNA levels of ICAM-1 and CXCL10 in groups C, D and E were higher ( P < 0.05). There were significant differences in the protein levels of p38, ICAM-1 and CXCL10 in thyroid tissue of the 5 groups of mice ( F = 7.97, 73.86, 18.02, P < 0.05); compared with group A, the protein levels of ICAM-1 and CXCL10 in groups B, C, D and E were higher ( P < 0.05). Conclusion:Excessive iodine promotes the occurrence and development of EAT in mice by up-regulating the expressions of p38 and ICAM-1 genes that are closely related to thyroid autoimmune and inflammatory responses.

One of the important causes of developmental epileptic encephalopathy (DEE) is the mutation of ion channel genes, including the mutation of the CACNA1E gene. CACNA1E-related DEE cases were first reported in 2018.The mutation types include new missense mutations, nonsense mutations and frameshift mutations, but the correlation between mutation sites and types with the phenotype of DEE is not clear.This review aims to summarize the reported CACNA1E-related DEE cases, and explore the correlation between the clinical phenotype of CACNA1E-related DEE and gene mutation sites and mutation types.Meanwhile, possible pathogenesis of CACNA1E-related DEE and the progress of drug intervention were reviewed to provide references for the diagnosis and precise treatment of DEE.

Objective To dynamic monitor drinking-water-borne fluorosis in Huzhu County and water improvement projects,to know the trend of the disease,and to evaluate the effect of prevention and control measures.Methods Seven townships in Huzhu County including 60 history drinking-water-borne fluorosis villages were selected as investigation sites in 2017,and demographic data were collected.In the villages of the diseased areas where the water had been changed,the operation of the water improvement project was investigated,and 1 tap water sample was collected to determine the fluorine content;for the villages in the diseased areas where the water had not been changed,one water sample was collected from the drinking water source in accordance with the five directions of east,west,south,north and middle to determine the fluorine content.More than 90％ of the children aged 8-12 years old in the surveyed villages were examined and judged for dental fluorosis.According to historical data,1 village with severe illness of children was selected,50 people were selected who were over 25 years old and lived in the villages for more than 5 years.Clinical and X-ray examinations of skeletal fluorosis were performed.Urine samples from adults surveyed were collected for urinary fluoride detection.Results Six of the 60 villages in the 7 townships had been relocated.By 2017,a total of 54 villages in drinking-water-borne fluorosis areas had changed their water.A total of 16 water improvement project were surveyed,among them,there were small water improvement project 6,accounting for 37.50％,large water improvement project 10,accounting for 62.50％;normal operated project 16,accounting for 100.00％;water fluoride content of qualified project 16,the qualified rate was 100.00％,the water fluoride content ranged 0.10-0.66 mg/L,covering a population of about 160 thousand and 846 people.A total of 2 399 children aged 8-12 were examined,117 cases of dental fluorosis were detected,the detection rate of dental fluorosis was 4.88％,dental fluorosis index was 0.13.Among them,89 cases were extremely mild,accounting for 3.71％ of all the children examined,21 cases were mild,accounting for 0.88％ of all the children examined,7 cases were moderate,accounting for 0.29％ of all the children examined,and no severe cases were found.A total of 68 adults over 25 years old were examined for skeletal fluorosis.Twelve patients were found to have clinical skeletal fluorosis.The detection rate was 17.65％.X-ray radiography was used to examine 46 people,and 1 case was detected,the detection rate was 2.17％.Clinical and X ray examinations showed no more than moderate patients.Fifty samples of adult urine were tested,the level of urine fluorine was 0.72 mg/L.Conclusions Water improvement project is working well in Huzhu County,and no serious children with dental fluorosis and adult skeletal fluorosis are detected.The prevention and control measures of drinking-water-bornefluorosis has achieved remarkable results in Huzhu County.We will continue to strengthen water improvement project and disease monitoring,and thoroughly control the prevalence of drinking water fluorosis.

Objective:To follow up the iodine nutrition and intellectual development of school children aged 8-10 years old in Nangqian County of Qinghai Province after 9 years of the implementation of iodine deficiency disorders intervention measures with iodine supplement as the main measure.Methods:In order to improve the iodine nutritional status of the population in Nangqian County, free iodized salt distribution, health education and other intervention measures for iodine deficiency disorders were implemented for 9 consecutive years since 2013. In May 2012 (before iodine supplementation) and September 2021 (after iodine supplementation), the same 5 townships (towns) were selected, and children aged 8-10 years old (half male and half female, age balanced) born locally in the central primary school of each township (town) were selected as the survey subjects. Household edible salt samples and random urine samples were collected for salt iodine and urinary iodine detection; the second revised version of the Chinese Combined Raven's Test (rural version) was used to assess the intelligence quotient (IQ) of children. The Flynn effect (FE) gain was used to adjust IQ, the corrected IQ = (IQ starting point value - current year's IQ value) - FE gain (calculated by 0.74/year). The differences of salt iodine and urinary iodine related indexes, IQ value and corrected IQ were compared before and after iodine supplementation.Results:After iodine supplementation, the coverage rate of iodized salt reached 100.00% (300/300), and the consumption rate of qualified iodized salt reached95.00% (285/300), the median urinary iodine increased to 157.20 μg/L, and all indexes met the elimination standard of iodine deficiency disorders. The IQ value of children aged 8-10 years old after iodine supplementation was 99.00 ± 14.90, significantly higher than that before iodine supplementation (82.00 ± 13.20, F = 156.82, P < 0.001). The FE gain in 9 years was 6.66, and the actual IQ gain of children aged 8-10 years old after iodine supplementation was 10.34. There were statistically significant differences in IQ value before and after iodine supplementation in male and female children ( F = 78.84, 78.88, P < 0.001). After iodine supplementation, there was a statistically significant difference in IQ value between children in the 8-year-old group and the 10-year-old group ( P = 0.010). There were statistically significant differences in IQ value before and after iodine supplementation in 8, 9 and 10 years old groups ( F = 55.23, 65.79, 36.85, P < 0.001). Conclusion:Intervention measures for iodine deficiency disorders, mainly iodine supplement, can significantly improve the iodine nutrition status of children aged 8-10 years old, and significantly promote the intellectual development of children.

Objective:To investigate the prevalence of adult skeletal fluorosis caused by drinking tea-type endemic fluorosis in Yushu Tibetan Autonomous Prefecture (hereinafter referred to as Yushu Prefecture), Qinghai Province, and provide scientific basis for prevention and control of the disease.Methods:In August 2021, one village was selected as a survey site in six counties (cities) in Yushu Prefecture, including Nangqian, Chindu, Yushu, Zadoi, Qumarlêb, and Zhiduo. Drinking water samples and 10 brick tea samples were collected from each village to determine the fluoride content in water and brick tea; at least 100 permanent residents aged ≥ 25, who had a habit of drinking brick tea and had lived in the local area for more than 5 years, were selected for X-ray imaging to examine the prevalence of adult skeletal fluorosis.Results:A total of 75 samples of residential drinking water were collected, with a fluoride content of (0.21 ± 0.05) mg/L, ranging from 0.11 to 0.34 mg/L; 60 samples of brick tea, with a fluoride content of (626.70 ± 157.27) mg/kg, ranging from 324.00 to 2 102.00 mg/kg. A total of 1 136 adults were examined, and 318 cases of skeletal fluorosis were diagnosed, with a detection rate of 27.99%. Among them, the detection rates of mild, moderate, and severe skeletal fluorosis were 20.95% (238/1 136), 6.07% (69/1 136), and 0.97% (11/1 136), respectively, with mild symptoms being the main. The detection rates of skeletal fluorosis in males and females were 29.09% (121/416) and 27.36% (197/720), respectively, with no statistically significant difference between the gender (χ 2 = 0.39, P = 0.533). Comparison of the skeletal fluorosis in different gender, the differences were statistically significant (χ 2 = 22.31, P < 0.001). The detection rates of skeletal fluorosis in the age groups of 25 - 35, 36 - 45, 46 - 55, 56 - 65, 66 - 75, and ≥76 years old were 6.86% (7/102), 22.37% (51/228), 24.02% (92/383), 37.44% (73/195), 43.48% (70/161), and 37.31% (25/67), respectively. The differences between the groups were statistically significant (χ 2 = 59.84, P < 0.001). Moreover, there was a statistically significant difference in the composition of skeletal fluorosis among different age groups ( H = 37.66, P < 0.001). The Spearman correlation analysis results showed that the severity of adult skeletal fluorosis was positively correlated with age ( r = 0.34, P < 0.001). Conclusions:There is a certain degree of prevalence of adult skeletal fluorosis in Yushu Prefecture. And as age increases, the condition of skeletal fluorosis becomes more severe.

As the progress of population aging in China, the proportion of elderly population is increasing. Both chronic diseases and infectious diseases can threaten the health of the elderly. There are many kinds of infectious diseases, including vaccine preventable infectious diseases affecting the health of adults, such as influenza, pneumococcal diseases and herpes zoster. In addition, the newly emerged COVID-19 has caused a pandemic in the world, resulting the highest proportion of deaths occurred in the elderly and posing a serious threat to the health of the elderly. This paper mainly summarizes the prevention and control of vaccine preventable diseases and COVID-19 to which the elderly are susceptible, analyzes the infectious disease problems affecting the health of elderly population, and recommends countermeasures for the prevention and control of these diseases in elderly population.