This article analyzes the concept,the formation process,the main content of the United States food defense plan,the duties of stakeholders and the key points of the implementation.This article also summarizes the characteristics,similarities and differences between China and the United States in terms of food defense system,discusses the difficulties and put forward some suggestions for the food defense plan in China.

Objective To explore the effects of different doses of sodium fluoride (NaF) on cartilage lesion and expression of interleukin-6 (IL-6) in serum and cartilage tissue of Balb/c mice.Methods Sixty-four 5-week-old male Balb/c mice were divided into 4 groups based on body weight via the random number table method and 16 mice were in each group.The mice in control group were fed with distilled water,and experimental animals in low,middle and high fluoride groups were fed with distilled water containing NaF 25,50 and 100 mg/L,respectively.The mice were weighed once a week and fed for three months to establish the drinking water fluorosis model.The fluoride contents in spine were detected via the fluorin-ion selective electrode method.The pathological changes in articular cartilage and epiphyseal plate cartilage were observed through optical microscope.The levels of serum IL-6 and souble IL-6 receptor (sIL-6R) were detected via the enzyme-linked immunosorbent assay.The expression of IL-6 protein in articular cartilage and epiphyseal plate cartilage was examined by immunohistochemistry.Results From the sixth week of the experiment,compared with other 3 groups,the body weight of high fluoride group decreased significantly (all P ＜ 0.05);from the seventh week,compared with control and low fluoride groups,the body weight of middle fluoride group decreased significantly (all P ＜ 0.05);throughout the experiment,compared with control group,the body weight of low fluoride group had not changed significantly (all P ＞ 0.05).The fluoride contents of bone in control group,low fluoride group,middle fluoride group and high fluoride group were (842.46 ± 89.27),(1 705.05 ± 105.76),(2 614.17 ± 156.10) and (3 444.58 ± 233.69) mg/kg,respectively.The differences between groups were statistically significant (F =309.716,P ＜ 0.05),and fluoride contents of bone increased with increase of fluoride doses (all P ＜ 0.05).Under optical microscope,the cartilage tissue of control group was normal,while articular cartilage and epiphyseal plate cartilage showed different degrees of cartilage ossification in fluorosis mice and the changes increased with the increase of fluoride doses.The levels of serum IL-6 in control group,low fluoride group,middle fluoride group and high fluoride group were (5.98 ± 1.43),(7.54 ± 2.16),(5.25 ± 1.97) and (6.31 ±-1.36) ng/L,respectively.The differences between groups were statistically significant (F =3.840,P ＜ 0.05),low fluoride group was significantly higher than control group (P ＜ 0.05),and middle fluoride group was significantly lower than low fluoride group (P ＜ 0.05).The levels of serum slL-6R in control group,low fluoride group,middle fluoride group and high fluoride group were (0.83 ± 0.20),(0.93 ± 0.23),(0.82 ±0.27) and (0.92 ± 0.28) μg/L,respectively.The differences between groups were not statistically significant (F =0.738,P ＞ 0.05).Immunohistochemical results showed that articular cartilage full-layer cells in each group expressed IL-6 protein especially in the middle layer of chondrocytes,while IL-6 protein only expressed in hypertrophic chondrocytes of epiphyseal plate cartilage.Comparing with other groups,IL-6 positive cells were the most and had the deepest staining in low fluoride group.Conclusions Different doses of NaF could not only cause cartilage lesion,but also change the expression of IL-6 in serum and cartilage tissue of Balb/c mice.The results indicate that IL-6 may be involved in the cartilage lesion caused by fluoride.

Objective To explore characteristics and significance of the indexes of peripheral white blood cell (WBC) in patient with human brucellosis.Methods People checked by brucellosis physical checkup and routine physical checkup at Qiqihar Center for Disease Control and Prevention from December 2014 to December 2015,including 40 acute brucellosis patients (acute group),35 chronic brucellosis patients (chronic group) and 72 healthy people (control group),were selected.Automatic blood analyzer was used to determine the indexes of WBC,lymphocyte count (LY),lymphocyte percentage (LY％),monocytes count (MONO),monocytes percentage (MONO％),eosinophil count (EO),eosinophil percentage (EO％),basophilic granulocyte count (BASO),basophilic granulocyte percentage (BASO％),neutrophils count (NEUT) and neutrophils percentage (NEUT％).The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value of WBC parameters in acute and chronic groups.Results Compared to control group,the levels of WBC,EO,EO％,BASO,BASO％,NEUT and NEUT％ were decreased in acute group [(5.222 0-± 2.551 2) × 109/L vs (6.352 5 ± 1.905 8) × 109/L,(0.030 0 ± 0.006 8) × 109/[,vs (0.083 9 ± 0.039 3) × 109/L,(0.54 ± 0.12)％ vs (2.31 ± 0.14)％,(0.009 0 ± 0.001 1) × 109/L vs (0.019 0 ± 0.002 4) × 109/L,(0.17 ± 0.09)％ vs (0.32 ± 0.20)％,(2.698 7 ± 1.948 4) × 109/L vs (4.012 9 ± 1.579 0) × 109/L,(48.13 ± 14.38)％ vs (62.13 ± 9.00)％,all P ＜ 0.05],and the levels of LY,LY％ and MONO％ were increased in acute group [(2.125 3 ± 0.949 9) × 109/L vs (1.794 4 ± 0.606 6) × 109/L,(43.37 ± 14.52)％ vs (29.10 ± 7.97)％,(7.84 ± 2.23)％ vs (6.55 ± 2.04)％,all P ＜ 0.05].Compared to control group,the level of NEUT％ [(54.63 ± 9.26)％] was decreased in chronic group (P ＜ 0.05),and the levels of LY,LY％ and EO [(2.212 0 ± 0.633 2) × 109/L,(36.41 ± 8.51)％,(0.153 9 ± 0.028 8) × 109/L] were increased in chronic group (all P ＜ 0.05).The levels of LY％ and MONO％ [(6.45 ± 1.58)％] in chronic group were lower than those in acute group (all P ＜ 0.05),and the levels of WBC [(6.175 7 ± 1.469 5) × 109/L],EO,EO％ [(2.32 ± 1.21)％],BASO [(0.021 8 ± 0.001 9) × 109/L],BASO％ [(0.37 ± 0.21)％] and NEUT％ were higher than those in acute group (all P ＜ 0.05).The areas under ROC curve (AUCs) of LY and MONO in acute group were 0.681 and 0.529,they were in 0.5-0.7,and the diagnostic value was low;the AUCs of EO,EO％,LY％,NEUT％,NEUT,BASO,BASO％,MONO％ and WBC in acute group were 0.816,0.816,0.806,0.790,0.766,0.760, 0.721,0.715 and 0.710,they were in ＞ 0.7-0.9,and the diagnostic value was medium.The AUCs of LY,NEUT,BASO,EO,BASO％,EO％,MONO％,MONO and WBC in chronic group were 0.693,0.617,0.586,0.584,0.581,0.541,0.500,0.513 and 0.510,they were in 0.5-0.7,and the diagnostic value was low;the AUCs of LY％ and NEUT％ in chronic group were 0.725 and 0.717,they were in ＞ 0.7-0.9,and the diagnostic value was medium.Conclusion The indexes of peripheral WBC in patient with acute and chronic human brucellosis are changed abnormally,which has a certain reference value in diagnosis of human brucellosis.

Objective To investigate the risk factors of severe hemolysis during extracorporeal membrane oxygenation (ECMO). Methods The clinical data of adult patients undergoing ECMO after cardiac surgery admitted to Fuwai Hospital from December 2010 to October 2015 were retrospectively analyzed. Demographic characteristics, renal function, primary disease, operation data, ECMO related data and outcomes were recorded. Patients were divided into normal free hemoglobin (FHB) group (FHB ≤ 500 mg/L) and severe hemolysis group (FHB > 500 mg/L) according to the FHB level during ECMO support. The parameters before and after ECMO support were compared between the two groups. Logistic regression was used to identify the independent risk factors of severe hemolysis. Results A total of 81 patients including 19 patients with severe hemolysis was enrolled, and 62 in normal FHB group. There was no difference in cardiopulmonary bypass (CPB) time, clamping time, lactate level before ECMO, cardiopulmonary resuscitation, intra-aortic balloon pump use and central catheter insertion between two groups. The maximums of serum creatinine (SCr) and FHB levels were higher in severe hemolysis group as compared with those in normal FHB group [maximal SCr (μmol/L): 281.02±164.11 vs. 196.67±87.31, maximal FHB (mg/L): 600 (600, 700) vs. 200 (100, 300)], the incidence of clots in circuit or oxygenator, infection, and hemofiltration in severe hemolysis group was increased [26.3% (5/19) vs. 4.8% (3/62), 31.6% (6/19) vs. 12.9% (8/62), 36.8% (7/19) vs. 14.5% (9/62), all P < 0.1]. As well as outcomes including the rate of site of surgery or intubation bleeding and acute renal failure [ARF, 57.9 % (11/19) vs. 30.6% (19/62), 94.7% (18/19) vs. 41.9% (26/62)], and the survival rate was lowered [10.5% (2/19) vs. 51.6% (32/62), all P < 0.05]. As result of univariate analysis, clots in circuit or oxygenator, infection and hemofiltration were associated with severe hemolysis. It was showed by logistic regression analysis that the clots in circuit or oxygenator was a risk factor of severe hemolysis during ECMO [odds ratio (OR) = 6.262, 95% confidence interval (95%CI) = 1.244-31.515, P = 0.026]. Conclusions The clots in circuit or oxygenator were independent risk factors of severe hemolysis during ECMO. Severe hemolysis can induce the increase of the rate of bleeding in the operation site or intubation and the rate of ARF, and decrease of the survival rate.

Objective To detect the modification levels of H2AKll9 ubiquitination (H2AK119ub) and H2BK120ub,and to analyze the relationship between the levels of H2AK119ub,H2BK120ub and arsenic exposure.Methods A cross-sectional study was conducted in typical areas of drinking water type of endemic arsenicosis in Shanxi and Jilin provinces.Totally 281 residents who had drank local water for more 10 years were enrolled in this study,these participants were divided into control group (water arsenic content ＜ 0.01 mg/L),low arsenic exposure group (water arsenic content ranged 0.01-0.05 mg/L),medium arsenic exposure group (water arsenic content ranged ＞ 0.05-0.10 mg/L) and high arsenic exposure group (water arsenic content ＞ 0.10 mg/L).Among them,including 60 subjects in control group (20 males and 40 females),61 subjects in low arsenic exposure group (27 males and 34 females),50 subjects in medium arsenic exposure group (17 males and 33 females),and 110 subjects in high arsenic exposure group (40 males and 70 females).Drinking water and urine samples were collected and the arsenic content was detected by the method of atomic fluorescence spectrometry.After extracting leukocytes histone from the peripheral venous blood that collected from the subjects,the levels of H2AK119ub and H2BK120ub were detected by dot blotting.The levels of water arsenic,urinary arsenic,water arsenic accumulative intake,H2AK119ub and H2BK120ub were expressed as medium and quartile [M (P25,P75)].Results Age,body mass index (BMI),gender,smoking and alcohol drinking between control group and water arsenic exposure groups had no statistical differences (x2 =3.780,3.572,1.938,4.937,6.025,all P ＞ 0.05).Compared the contents of water arsenic [0.005 (0.003,0.006),0.024 (0.017,0.037),0.076 (0.057,0.084),0.150 (0.124,0.185) mg/L],the contents of urinary arsenic [0.011 (0.006,0.017),0.018 (0.004,0.072),0.061 (0.032,0.124),0.134 (0.069,0.223) mg/L],the water arsenic accumulative intake [0.342 (0.248,0.477),1.641 (1.012,2.324),5.273 (3.690,7.036),7.716 (5.608,12.053) mg] among the control,low,medium and high arsenic exposure groups,the differences were statistically significant (Hc =256.041,88.615,218.610,all P ＜ 0.01).Compared the levels of H2AK119ub [1.231 (0.856,1.817),1.244 (0.792,1.884),1.376 (0.743,1.981),1.390 (0.906,2.045)],H2BK120ub [0.350 (0.186,0.589),0.363 (0.152,0.678),0.428 (0.134,0.788),0.276 (0.146,0.453)] in human peripheral blood leukocytes among control,low,medium and high arsenic exposuregroups,the differences were not statistically significant (Hc =2.130,4.330,all P ＞ 0.05).There were no correlations between H2AK119ub and water arsenic content,water arsenic accumulative intake (r =0.104,-0.008,all P ＞ 0.05);there was a positive correlation between H2AK119ub and urinary arsenic content (r =0.166,P ＜ 0.05).There were negative correlations between H2BK120ub and water arsenic content,water arsenic accumulative intake (r =-0.183,-0.159,all P ＜ 0.05);there was no correlation between H2BK120ub and urinary arsenic content (r =-0.101,P ＞ 0.05).There was a negative correlation between H2AK119ub and H2BK120ub (r =-0.127,P ＜ 0.05).Conclusion External exposure to arsenic may change the levels of H2BK120ub in human peripheral blood leukocytes.

Objective: To summarize the peri-operative management experience of pulmonary endarterectomy (PEA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). Methods: A total of 56 CTEPH patients received PEA in our hospital from 2015-01 to 2016-11 were retrospectively analyzed. Our study was focused on the medication in respiratory and circulatory system during ICU stay, peri-operative application of vasoactive drug and target drug to pulmonary hypertension (HP), usage of ventilators, mechanical assisted devices and other management experiences. Results: No peri-operative death occurred. There were 2/56 (3.6%) patients with lung reperfusion, 2 (3.6%) with PH crisis. Compared with pre-operation, the post-operative pulmonary artery hemodynamics parameters were improved as right heart catheter measured pulmonary artery systolic pressure (PASP) decreased from (85.05±22.40) mmHg to (36.83 ±17.21) mmHg and pulmonary vascular resistance decreased from (773.84±342.95) dyn·s·cm-5 to (293.59±214.95) dyn·s·cm-5. Post-operative oxygen saturation was maintained at (95-100) % in all patients. Echocardiography found that PASP from pre-operation (85.03±25.78) mmHg decreased to (39.44±19.24) mmHg at follow-up period, P<0.01.Conclusion: A comprehensive peri-operative management of PEA was helpful to improve pulmonary hemodynamics in CTEPH patients; meanwhile, effective prevention and treatment of severe complication could obviously reduce peri-operative mortality.

Objective To investigate the relationship between Cytochrome P-450 1A1 (CYP1A1) gene polymorphism and the ethnic differences to brick-tea fluorosis and the gene-environment interaction.Methods Inhabitants over the age of 16 years old in Inner Mongolia,Qinghai and Xinjiang were investigated.The questionnaire survey included basic information,dietary survey and total fluoride intake,and peripheral venous blood was collected.The CYP1A1 gene single nucleotide polymorphism (SNP) genotyping was determined using mass spectrometry;the diagnosis of skeletal fluorosis was based on the X-ray method;combined genetic factors with environmental factors,the interaction of gene-environment was analyzed.Results In the 1 414 copies of whole blood samples (308 Tibetans,290 Kazakhs,261 Mongolians,425 Han people,130 Russians),CYP1A1 genes rs1048943 sites were typed into AA,AG and GG genotypes,and gene distribution met Hardy-Weinberg equilibrium (P ＞ 0.05).The frequencies of genotypes AA,AG and GG in Tibetans were 55.8％ (172/308),37.3％ (115/308) and 6.8％ (21/308),respectively;the frequencies of the three genotypes in Kazakhs were 69.7％ (202/290),27.6％ (80/290) and 2.8％ (8/290),respectively;the frequencies of the three genotypes in Mongolians were 60.5％ (158/261),36.0％ (94/261) and 3.4％ (9/261),respectively;the frequencies of the three genotypes in Han people were 60.9％ (259/425),33.6％ (143/ 425) and 5.4％ (23/425),respectively;the frequencies of genotypes in Russians were 72.3％ (94/130),26.9％ (35/130) and 0.8％ (1/130),respectively;the differences of the three genotype frequencies between different ethnic groups were statistically significant (x2 =24.757,P ＜ 0.05).The skeletal fluorosis detection rates in different ethnic from high to low were Tibetans (39.94％,123/308),Kazakhs (33.79％,98/290),Mongolians (22.22％,58/261),Han people (13.41％,57/425) and Russians (8.46％,11/130),and the differences were statistically significant (x2 =100.156,P＜ 0.05).Skeletal fluorosis detection rates of different genotypes were AA (24.18％,214/885),AG/GG (25.14％,133/529),the difference was not statistically significant between the groups (x2 =0.165,P ＞ 0.05).After the ethnic stratification,the differences were also not statistically significant (P ＞ 0.05).Only in the group of Tibetans whose urine fluoride level was 1.6-3.2 mg/L and Mongolians under age 45 were found that the G gene was one of the risk factors in skeletal fluorosis [OR =2.035,95％ CI (1.003-4.128);OR =5.602,95％CI (1.461-21.479)];G gene might be a protective factor in the Mongolians aged 45 years and over [OR =0.422,95％CI(0.190-0.938)].Conclusion This study does not find a positive correlation between CYP1A1 gene polymorphism and the ethnic differences to bricktea fluorosis.

Objective To study the value of endothelin-1 (ET-1) in predicting the outcome of stable coronary artery disease (SCAD) patients.Methods A total of 3154 SCAD patients who were followed up for 24 months were divided into cardiocerebral vascular events group (n=189) and cardiocerebral vascular events-free group (n =2965).Their serum ET-1 level was measured by ELISA.The patients were further divided into ET-1 ＜0.3 pmol/L group (n=1588) and ET-1≥0.3 pmol/L group (n=1566).The value of ET-1 in predicting the end events was assessed by Cox regression analysis.The survival curve was plotted by Kaplan-Meier analysis.Results The serum ET-1 level was signify-cantly higher in cardiocerebral vascular events group than in cardiocerebral vascular events-free group (0.33 pmol/L vs 0.30 pmol/L,P=0.004).The incidence of clinical end events was significantly lower in ET-1 ≥0.3 pmol/L group than in ET-1 ＜0.3 pmol/L group (7.02％ vs 4.97％,P=0.015).Multivariable Cox regression analysis showed that ET-1 was a predictor of clinical end events (HR=1.656,95％CI:1.099-2.496,P=0.016).Kaplan-Meier analysis showed that the events-free survival rate was lower in patients with a higher serum ET-1 level than in those with a lower serum ET-1 level (P=0.016).Conclusion ET-1 is an important risk factor for the outcome of SCAD patients.Further studies are needed to confirm its long-term value in predicting the outcome of SCAD patients.

Objective To investigate the relationship between single nucleotide polymorphism(SNP)of the peroxisome proliferator activated receptor γ (PPARγ) gene Rs1801282 and brick-tea type fluorosis. Methods From 2012 to 2013, this cross-sectional study was performed in 16 endemic fluorosis areas of brick-tea type in Inner Mongolia Autonomous Region,Qinghai and Xinjiang Uygur Autonomous Region of China,to select adults>18 years old as subjects, who were diagnosed as skeletal fluorosis by X-ray. All of the subjects filled in demography survey questionnaire; the survey contents included general characteristic s, and average daily brick tea intake. Drinking tea samples and urine samples of each subject were collected, and fluoride content of urine and brick-tea was determined via the ion selective electrode method (WS/T 89-2006). X-ray scintigraphy was used to diagnose skeletal fluorosis, according to the "Diagnostic Criteria of Endemic Skeletal Fluorosis" (WS/T 192-2007); the subjects were divided into skeletal fluorosis group (case group) and non-skeletal fluorosis group (control group). To collect venous blood 5 ml, whole blood DNA was extracted, and polymorphism at Rs1801282 of PPARγ was detected by MassARRAY time-of-flight mass spectrometry, to calculate odds ratio (OR) and 95% confidence interval (CI). Results There were 1 414 people included in this study,including 347 in case group and 1 067 in control group. By the Hardy-Weinberg balance test, the PPARγ gene Rs1801282 genotype was representative in case group, control group and each nationality (P > 0.05). The difference of PPARγ gene Rs1801282 genotype in case group and control group was not statistically significant (OR was 0.991, 95%CI: 0.704 - 1.395, the adjusted OR was 1.026, 95%CI: 0.707-1.489).The difference of PPARγ gene Rs1801282 genotype(CC,CG+GG)in case group and control group in different nationality was not statistically significant (Tibetan: OR was 1.400, 95%CI: 0.576 - 3.404, the adjusted OR was 1.258, 95%CI: 0.474 - 3.340; Kazak: OR was 0.898, 95%CI:0.516 -1.562,the adjusted OR was 0.936,95%CI:0.532 -1.648;Mongolia: OR was 1.148,95%CI:0.508-2.594, the adjusted OR was 1.644, 95%CI: 0.683 - 3.956; Han: OR was 1.058, 95%CI: 0.451 - 2.482, the adjusted OR was 0.959, 95%CI: 0.388 - 2.371; Russian: OR was 0.000, 95%CI: 0.000 - 0.000, the adjusted OR was 0.000, 95% CI: 0.000 - 0.000) with binary Logistic regression analysis. Conclusion We have found no association between SNP of PPARγ gene Rs1801282 and skeletal fluorosis of brick-tea type fluorosis in China.

Objective To study the urinary arsenic safety guideline value of a population for evaluating the arsenic exposure level in a certain population and providing evidence for the implementation of prevention and control measures in endemic arsenicosis area.Methods According to the data from the national high-arsenic drinking water sources screening in endemic arsenicosis area of drinking water type and quality supervision and inspection for water-improving project to decrease arsenic from 2005 to 2014,census data on arsenic poisoning in endemic arsenicosis area,data on surveillance of endemic arsenicosis,10 722 people with detailed personal information,complete water arsenic exposure data and accurate urinary arsenic detection data were selected to be the research objects.The relationship between urinary arsenic and water arsenic was analyzed based on the surveillance data of 4 501 people from 2013 to 2014.The safety guidance value of urinary arsenic was determined based on the geometric mean value of urinary arsenic in people exposed to water arsenic in the range of (0.050 ± 0.005) mg/L,and verified using the data of 6 221 people from 2005 to 2012.Every time,a random sample of 2 000 people was taken as the verification sample,the sensitivity and specificity of the index for determining whether water arsenic exposure exceeded the standard were determined by area under the ROC curve (AUC),and a total of 10 sample tests was performed.Results When the water arsenic concentration was less than 0.01 mg/L,the correlation coefficient of water arsenic concentration with urinary arsenic concentration was 0.097 (P ＜ 0.01);when the water arsenic concentration was more than 0.01 mg/L and less than 0.05 mg/L,the correlation coefficient of arsenic concentration with water arsenic concentration was 0.456 (P ＜ 0.01);when the water arsenic concentration was more than 0.05 mg/L,the correlation coefficient of water arsenic concentration with urinary arsenic concentration was 0.630 (P ＜ 0.01).With increase of water arsenic concentration,the concentration of urinary arsenic increased significantly,and the difference was statistically significant (x2 =2 337.956,P ＜ 0.01).When water arsenic concentration was in the range of (0.050 ± 0.005) mg/L,the urinary arsenic geometric mean was 0.032 mg/L.AUC analysis of 10 random samples of 2 000 people showed that the geometric mean of urinary arsenic was 0.032 mg/L in the population,which can accurately distinguish whether the water arsenic level exceeded 0.05 mg/L,and the AUC value was higher than 0.94.And the sensitivity and specificity were achieved 0.898 and 0.844.Conclusions The geometric mean of urinary arsenic is 0.032 mg/L,which can be used as a safety guideline value for urinary arsenic in the population.When the geometric mean of urinary arsenic exceeds this value,the population may be exposed to high arsenic.