Abstract:To understand enterotoxin genes distribution and molecular characteristics of foodborne Staphylococcus aureus isolated from Ningbo.Methods Enterotoxin gene A,B,C and D were detected by polymerase chain reaction (PCR). Molecular characteristics were acquired by multi-locus sequence typing (MLST).Results 190 strains of foodborne S.aureus were isolated during 2005-2012.41 strains were positive for enterotoxin gene. The positive rate of 4 enterotoxin genes were 7.37%, 5.26%, 8.95% and 5.79%, respectively. 13 strains harbored at least two enterotoxin genes. 41 strains could be divided into 9 kinds of enterotoxin gene spectrum and 12 sequence types (STs) by MLST. ST5, ST6, ST188 and ST1 were the major STs. The positive rate of 4 STs was 75.61%. Four branches were formed in the phylogenetic tree.Conclusion The positive rate of enterotoxin gene was relatively high in foodborne S.aureus during 2005-2012, and monitoring needed to be strengthened. There were significant difference in molecular typing between the strains with enterotoxin gene in Ningbo and those food isolates from other part of China.

Abstract:The aim of this research was to establish a novel method based on tdh1 gene variation for identifying V.parahaemolyticus pandemic strains.Methods tdh sequences from various strains were compared, and specific sites for pandemic strains were searched. Allele-specific PCR was established based on the selected site, and verified by known isolates and isolates from 2014, compared with the joint of GS-PCR and tdh method as a reference methods. Results 26 sites in 6 tdh sequences from 3 isolates showed polymorphism, and only the 368^th base could be used to identify pandemic strains. tdh1_368 allele-specific PCR was based on this site which could discriminate pandemic O3∶K6 strains before and after 1996. This method could also discriminate other serovariants of pandemic strains from non-pandemic strains. According to the detection of 1 067 isolates from 2014, complete consistent was showed between the novel method and the reference method.Conclusion tdh1_368 allele-specific PCR was useful for V.parahaemolyticus pandemic strains identification, and the detection target was more simple and direct compared with the methods reported. It was the first time to use this mutation for pandemic strains identification.

Abstract:To study the distribution of virulence genes, evaluate the virulence of food-borne Bacillus cereus in Shijiazhuang City, and to investigate the potential risk.Methods 9 virulence genes (such as enterotoxin and voitoxin) were detected with PCR method in 131 Bacillus cereus collected from food risk monitoring program. The virulence of pathogens were also analyzed using blood agar plates. Results The carrying rate of virulence genes was high. 99.2%(130/131) of the strains carried at least one virulence gene. hblACD and entFM were the major virulence genes of Bacillus cereus in Shijiazhuang City. All strains produced hemolysin BL.Conclusion Diarrhea enterotoxin was widespread in food, and hemolysin was detected in all pathogens, which caused potential public health risk. More effective monitoring strategies should be developed to prevent and control the occurrence of Bacillus cereus food-borne diseases.

Abstract:The comparative study of serotypes and virulence genes of Vibrio parahaemolyticus isolated from contaminated aquatic products and infection cases in Beijing not only provided clues for the assessment of food safety risk monitoring, but also offered technical support on the correlation research of aquatic products contaminated by Vibrio parahaemolyticus and clinical infections.Methods Vibrio parahaemolyticus isolates were separated from aquatic product and stool samples of patients with diarrhea. Serotypes were tested by serum agglutination. tlh, tdh and trh gene of the strains were detected by PCR. Results 164 aquatic product samples were collected from July to September. Vibrio parahaemolyticus was isolated from 80 aquatic product samples. Total incidence of Vibrio parahaemolyticus was 48.78%. The incidence of Vibrio parahaemolyticus in sea products was 53.04%, and the incidence of Vibrio parahaemolyticus in freshwater products was 38.78%. The average concentration in sea products was 38.14 MPN/g, and was 66.63 MPN/g in freshwater products. 80 isolates were divided into 9 O serogroups, among which O2 (35.00%), O1 (13.75%) and O5 (12.5%) were the main serotypes. All 80 isolates had tlh gene, only 1 isolate had tdh gene, and no trh gene was detected. From stool samples of sentinel hospital patients with diarrhea, 21 Vibrio parahaemolyticus strains were isolated and identified. Among 21 clinical strains, 13 strains were O3∶K6 serotype, and 6 strains were O4∶K8 serotype, with the ratio of 61.90% and 28.57% respectively. Virulence genotype tdh(+)/trh(-) had 20 strains, tdh(-)/trh(-) had 1 strain, with the ratio of 95.24% and 4.76% respectively.Conclusion China's food safety risk monitoring was mainly to evaluate the occurrence of foodborne illness through monitoring in Vibrio parahaemolyticus in aquatic products. Most of the Vibrio parahaemolyticus strains isolated from aquatic product samples were not pathogenic, but all the Vibrio parahaemolyticus which led consumers to diarrhea carried pathogenic virulence genes, indicating that the current food safety risk monitoring results were not accurate for evaluating foodborne disease outbreaks or sporadic caused by Vibrio parahaemolyticus.

Abstract:Analysis and comparison of crude fat expression effect of five kinds of WRI1 transgenic rice.Methods The coconut WRI1 gene (regulation genesof fatty acid synthesis ) was introduced into japonica rice zhonghua11, and 5 transgenic plants, ZZWR1, ZZWR2, ZZWR3, ZZWR4 and ZZWR5 were obtained. The crude fat of the transgenic rice and control rice was extracted by Soxhlet extraction method and determined qualitatively and quantitatively using GC-MS method.Results Compared with the control rice which contained 2.59% crude fat, the contents of ZZWR1, ZZWR2, ZZWR4 were from 2.62% to 2.77%, which was significantly higher than the control rice. ZZWR4 was the highest with RSD of 0.96%. Palmitic acid methyl ester, methyl stearate and methyl oleate were quantified by GC-MS , and methyl oleate was the highest.Conclusion Coconut WRI1 gene introduced into rice could improve rice fat content. The different insertion sites of WRI1 gene may influence the original fatty acid expression. ZZWR4 insertion site had better expression.

Abstract:The aim of this study was to investigate subchronic toxicity of Flos Puerariae.Methods According to procedures and methods for toxicological assessment of food (2003 edition), eighty SD mice were randomly divide into four groups (10 male and 10 female in each group). 0,6.25,2.5,5.0 g/kg.BW of Flos Puerariae extract were given by gavage for 90 days respectively. On the 45th day, samples of blood were collected from tails to perform complete blood count and biochemical tests. After 90 days, samples of blood were collected and were used for blood count and biochemical tests; livers, kidneys, spleens and testicles(ovaries) were weighed; pathological examinations of livers, kidneys, spleens stomach intestines testicles and ovaries were conducted. Results The results showed that indexes including weight, food intakes, food utilizations, and organ-body ratios in treatment groups are not significant different from those in the control group (P>0.05); in the interim and at the end of experiments, the blood count and biochemical tests of some certain treatment groups have statistical difference (P<0.05); however, the difference is in a normal range and has no biological significance; minor pathological changes have been discovered in a few treatment groups through the histopathology examination.Conclusion Flos Puerariae extracts have no adverse effect on the growth performance of mice under the doses of pueraria flower in a range of 6.25-25.00 g/kg BW. Moreover, Flos Puerariae extracts haven't caused obvious toxic and side effects on experimental animals.

Abstract:To evaluate the current situation of the ability of epidemiology in food poisoning in local CDC by assessment of reports.Methods Reports of food poisoning above 20 people was collected. According to Guidelines for Foodborne Disease Outbreak Response, 30 index in 6 chapters was chosen to evaluate. Results 102 reports were evaluated. 99% of the reports recorded the accurate time and brief progress, but only 27% of them included the indicator case, 36% included RR, 44%included the definition of cases. 58 reports needed to carry out analytical epidemiology, but only 21% had the results and 16% calculated OR or RR. 13% of the reports analyzed the food contamination source, 36% investigated the food processing. 96% of the reports contained lab results, but only 87% analyzed the results. 70% of the reports gave out the exact pathogen, 48% found the contaminated food, and 40% found the contamination cause. Only 5.9% of the reports described the results of descriptive epidemiology completely. 2.9% described the investigation of hygiene completely, 46% described the test results completely, 13% made the conclusion completely. Only 1 report reached the requirement of the guidelines. Conclusion Food poisoning reports in Guangdong Province could not reach the requirement of guidelines which lack of analytical epidemiology. The ability of epidemiology in food poisoning in local CDC needed to be improved.

Abstract:The purpose of this research is to establish and optimize a new method for accurate and rapid capillary electrophoresis-chemiluminescence detection of fumonisin B₁.Methods The conditions for luminescence were optimized based on the effect of fumonisin B₁ on the chemiluminescence system of Ag(Ⅲ) and lumonol. The buffer solution was 2×10-3 mol/L luminol solution containing 5×10-3 mol/L borax, and the oxidation reagent was the 3×10-5 mol/L Ag(Ⅲ) solution containing sodium hydroxide. Results After optimization of separation and detection, the linear range was from 1 to 200 μg/ml, and the detection limit (S/N=3) was 1 μg/ml. On the eight parallel detections of 200 μg/ml fumonisin B₁, the relative standard deviations of peak time and peak height were 2.64% and 7.86%.Conclusion The method is simple, rapid, accurate and reliable for the detection of fumonisin B₁, and could be applied to detect fumonisin B₁ in corn.

Abstract:To establish a rapid screening and confirmation method for pesticide residues in tea using UPLC-MS/MS for instrument method and QuEChERS for sample preparation.Methods The pesticide residues were extracted from tea samples with acetonitrile, and purified by dispersion solid phase extraction (d-SPE) using N-propyl ethlene diamine (PSA), graphitized carbon black(GCB) and triple phase of tea(TPT). The pesticide analytes were then separated on a reversed phase column using a gradient elution program. The ion fragment were obtained using ultra high performance liquid chromatography-tandem mass spectrometry under multiple reaction monitoring mode and quantified by the external standard method. Results In checking tea sample, 10 pesticide were screened qualitatively and carried on the quantitative analysis. The method showed a good linearity (r>0.999) in the ranges of 0.1-20 μg/L for 10 pesticide with average recovery rates of 75.7%-105.8% and the relative standard deviation (RSD) of 2.3%-18.4%. The limits of quantification (LOQs) for 10 pesticide were between 0.5 and 2 μg/kg.Conclusion The method was simple, sensitive and accurate, and was suitable for confirmation multi-residue pesticides in agricultural products.

Abstract:A method of determination of lead in high salty food by GFAAS was established, and the interference model, various matrix modifiers, temperature program and correction model were explored.Methods Lead in high salty food was measured by standard addition method with Pd(NO₃)₂-NH₄H₂PO₄ as mixed matrix modifier after four kinds of pretreatment methods including microwave digestion, wet digestion, high-pressure tank digestion and direct dilution were adopted. Results While the salinity was below 2.2%, the interference could be eliminated by standard addition method with Pd(NO₃)₂-NH₄H₂PO₄ at the wavelength of 283.3 nm. The linear range was 1.8-40 μg/L. When 0.5 g sample were diluted to 10 ml, the limit of quantification was 0.036 mg/kg.Conclusion This method could eliminate the interference of high salinity during lead determination by GFAAS and improve the accuracy and reliability. The study provided good technical reserves for the revision and integration of national standards were established.

Abstract:To develop a fast and sensitive Real-Time PCR method with a short (3-5 h) enrichment to detect and quantify E.coli in food.Methods Experiments were performed with E.coli(ATCC 25922) as the reference strain. The optimal enrichment conditions were established from different medium and different temperature. Both quantification calibrators and samples were enriched for 3-5 h in the optimal enrichment medium. DNA was extracted using Triton-X 100 method, and was amplified using an E.coli-specific PCR assay targeting the specific gene. Standard curves were created by plotting the cycle threshold (Ct) values against the logarithm of the original quantity of reference strain (before enrichment), and samples were calculated from the respective Ct value.Results Under the conditions of pure E.coli growing in NB, standard curves showed a good linearity, with r²of 0.996,0.992 and 0.991 for 3,4 and 5 h enrichment respectively, and the corresponding limits of detection (LOD) were 136,4 and 1.4 cfu/100 ml, respectively. This method was validated by creating standard curves after the 4 h enrichment in NB and EC with background microorganisms at 42.0 ℃,with r²of 0.972 and 0.978, respectively. This method also tested the natural and spiked food samples, with a recovery rate from 74.0% to 174.0%. Conclusion The Real-Time PCR with 3-5 h enrichment is a rapid, accurate and reliable technique for quantifying the viable E.coli cells in food..

Abstract:This paper reports a new, simple and rapid method to determine histamine, cadaverine, putrescine, tyramine, tryptamine, spermine, spermidine and β-phenylethylamine in wine without sample pretreatment.Methods Following automatic online derivatization with a mixed solution of cysteamine and o-phthaldialdehyde, eight kinds of biogenic amines in wine were separated on a high performance liquid chromatography instrument with a C₁₈ column. Results The linear range of the proposed method was validated in the range 0.25-10 mg/L. The relative standard deviation was less than 5%, and the intermediate precision ranged from 2.5 to 6.3%. The recoveries varied from 91.2% to 104.1%, and the detection limits varied from 20 to 100 μg/L for the eight kinds of biogenic amines.Conclusion The method is able to accurately determine the content of eight kinds of biogenic amines in wine with good reproducibility, accurate quantization and without sample pretreatment.

Abstract:Based on Vibrio parahaemolyticus real-time fluorescent quantitative PCR method, rapid detection method of Vibrio parahaemolyticus was developed.Methods According to the Vibrio parahaemolyticus gene sequences published in GenBank, specific target genes were selected for primers and probes design, and the reaction system was optimized. An internal amplification control (IAC) was added to the raction system. This IAC was detected by TaqMan probes labeled with different fluorophore. The samples were artificially contaminated in 5-50 cfu/25 g, and were used to evaluate the performance of the reaction system. Results The assay could be used reliably for detection of Vibrio parahaemolyticus with the sensitivity of 1 pg/μl. For the 10-fold dilutions bacteria DNA extracted by cooking water, the lowest detection limit was 4×10² cfu/ml; and for the plasmid with gyrB, the lowest detection limit could reach 100 copies/μl. The standard curves of gyrB and gyrB-IAC were established, which the quantification was linear between Ct and template copy number (r²=0.999). When the initial sample amount of artificially contaminated bacteria was 7 cfu/25 g seafood, the Vibrio parahaemolyticus could be detected after 6 hours culture.Conclusion The gyrB-IAC fluorescence quantitative PCR assay was developed. It could not only be applied for detection of Vibrio parahaemolyticus in food, but also monitor the PCR reaction system to prevent ‘false negatives'. Therefore, the gyrB-IAC fluorescence quantitative PCR assay further ensures the reliability of the results and is helpful to standardize quantitative PCR method for Vibrio parahaemolyticus in seafood.

Abstract:To establish a method for the determination of sulfur dioxide in paprika by ion chromatography.Methods After the sample being crushed in acidic condition, sulfur dioxide in the sample was distilled and oxidized to sulfate by H₂O₂, and determined by ion chromatography. Results The calibration curve was linear in the concentration range of 0-667.0 mg/kg (r=0.999 9), the recovery was in the range of 82.79%-108.7%, the relative standard deviation (RSD) was less than 5%, and the limit of detection of sulfur dioxide was 0.1 mg/kg.Conclusion This simple method has less interference, good specificity, accuracy and sensitivity.

Abstract:To assess the epidemiologic investigation capacity to food safety incidents among prefectural and local CDC in Guangdong Province and provide references for health emergency management strategies and training programs planning.Methods Related institution chiefs of 124 prefectural and local CDCs in Guangdong Province were interviewed by E-mail with a questionnaire, which contained 35 items and four parts including staff composition, education and training, emergency response, and financial support. Results It was shown that the staff composition was basically reasonable, while staff numbers were generally limited. Compared with non-Pearl River Delta region, CDC staffs in Pearl River Delta region had more FETP training opportunities. Most prefectural CDCs and local CDCs had their own emergency plans, but never trained. For technical manuals or standards, the ratio of training would be higher. Case interview questionnaires were all prepared, but not unified. Most CDCs were equipped with sampling tools in the field and supplemented periodically, and Pearl River Delta region CDCs were equipped better. Information resources of food safety incidents were mainly from hospitals (74.2%). Task orders of food safety incidents were mainly from DOH (79.8%). Results of simulating case interview suggested the field epidemiology capacity, such as confounding factors eliminating, analytic epidemiology, statistical analysis and process, specimen collecting and testing items confirming, need to be improved greatly, especially in the local level. Great financial gaps for epidemiologic investigation of food safety incidents generally existed in CDCs. The ratio of financial funding from government in prefectural CDCs was 82.8% and local CDCs was 64.1%.Conclusion Staff and financial gaps, epidemiology capacity and differences among regions are very common in prefectural and local CDCs of Guangdong Province. The government should enhance the staff and financial support. CDCs should enhance the development of epidemiology investigation capacity to food safety incidents.

Abstract:Nutrition, health and related claims regulation in Australia is systematically introduced, including definition and classification, laws and regulations, and administration mode etc. Comparative analysis of nutrition, health claims regulation between Australian and China is reviewed. Related regulation is explored and regulation suggestions is put forward to related authorities and researchers.

Abstract:To understand the current situation of purchasing behavior and safety cognition of parents towards children's snacks, and to provide effective suggestions according to the characteristics of parents to protect children's health.Methods The purchasing behavior and safety cognition of 350 parents towards children's snacks in the rural area of Hebei Province were investigated by questionnaire. Arandom class from each grade from grade 1 to 6 was chosen and all studentsin the class were chosen as targets. The questionnaire was answered by children's parents. The results were analyzed by both descriptive statistics and factor analysis and cluster analysis by SPSS 21.0, parents were divided into different groups with different safety cognition. Results 60.3% of parents chose the small shops as the No.1 choice to purchase snacks and 70% of parents chose convenience as the No.1 factor when consider where to buy. 86.6% and 81.4% of the parents concerned the shelf-life and date of manufacture as main safety factors. The top 5 snacks parents purchased for children were sausages, candies, cake/pies, dairy products and instant noodles. 63.9% parents purchased sausages frequently. Parents did not pay much attention on the children's self-purchasing behavior and did not provide effective guidance. According to the degree of the safety cognition of snacks, parents were classified into three groups:passive parents, autognosis parents and learning parents.Conclusion It was critical to improve safety cognition of parents in rural area. The classification of parents according to their characteristics could promote a better education result through their well-directed way.

Abstract:To understand the implementation, comprehension, and compliance of national food safety standard GB 7718-2011 The General Principles of Prepackaged Food Labels among industries, supervision department, inspection agency and research institutions in Anhui Province, and to provide information for future revision.Methods Cross-sectional survey was done from July to October, 2013 by meeting, E-mail, fax and other forms to complete the questionnaire. The respondents were selected from the staffs from enterprises, supervision department, inspection agency and research institutions. The information of survey included the basic situation, general understanding, main problems in the process, suggestions and comments. Results The number of valid questionnaire screened from enterprise, supervision, inspection and research institutions were 35,5, 28,2 respectively, and feedback articles were 46,8, 22 and 17, respectively. The awareness rate of the standard was 92.0%. Most of the respondents considered the standard to be reasonable and practical. The frequency of use from the staffs in enterprises and supervision department was higher than others. Items such as the label content of prepackaged food provided directly to the consumers, mandatory labeling of allergen and the label form of food additives in the ingredient list were the main contribution part of the feedback problems.Conclusion The follow-up study indicated that the standard was generally reasonable and practical, but the science-base and practicability of some terms should be enhanced. It is recommended that more attention should be paid on the training for different stakeholder, especially small and medium-sized enterprises and regulators.

Abstract:To understand the current status of nutrition labeling, nutrition claims and nutrition function claims on prepackaged foods in Henan Province.Methods Photographs of prepackaged foods was taken and input to the database. The compliance check was performed and analyzed by SPSS. Results The 1 031 prepackaged foods from 9 categories were investigated. 970 prepackaged foods had nutrition label and the rate was 94.08%. 49 prepackaged foods were labeled with nutrition claims and the rate was 4.75%. Nutrition claims were focused on calcium, iron, zinc and vitamin.Conclusion Most of the prepackaged foods in Henan Province were labeled according to the standard. The labeling rate had increased, but the label was not accurate and normative. The supervision and inspection of nutrition labeling should be enhanced.

Abstract:To understand the distribution characteristics of heavy metal contamination in dairy products, and to evaluate the status and the extent of heavy metal contamination.Methods The contents of Pb, total-Hg, Cd, Cr and total-As in raw milk, fermented milk, sterilized milk, infant formula and milk powder during 2012-2013 were detected. Single factor contamination index method and comprehensive contamination index method of Nemerow were used to evaluate the contamination level according to the grading standard of agriculture product quality. Results The detection rate of Pb, total-As, total-Hg, Cd and Cr were 14.0%(21/150), 24.7%(37/150), 82.0%(109/133), 26.3%(35/133)and 72.9%(43/59) in dairy products, respectively. Pb in raw milk and Cd in sterilized milk were not detected. The mean, P75 and P95 of total-Hg in raw milk were higher than the limit. The P95 of total-Hg in fermented milk and sterilized milk and Cd in milk powder were higher than the limit. The detection rate and single factor contamination index of total-Hg were the highest in raw milk, fermented milk and sterilized milk, which indicated there was severe contamination in the raw milk(PHg>1) and mild contamination in fermented milk (PHg>0.6). The detection rate of Cr was the highest in infant formula and milk powder, while single factor contamination index of Cd was the highest. The heavy metal contamination in raw milk ranked the first with P_n=0.754, reaching mild level of contamination. The heavy metal contamination in dairy products could be lined in a decreasing order of raw milk, fermented milk, sterilized milk, milk powder and infant formula.Conclusion Four kinds of dairy products were at the safe level of heavy metal contamination. Total-Hg was the dominant heavy metal contamination in liquid milk, while Cd in solid milk. Single factor contamination index and comprehensive contamination index of total-Hg in raw milk indicated that measures should be taken to prevent the contamination.

Abstract:Evaluate relative risk of listeriosis for sensitive population in China among selected categories of ready-to-eat foods at retail.Methods Relative risk for per serving and per annum of 5 major kinds, 17 categories ready-to-eat food were estimated by using food contamination data of Listeria monocytogenes during 2010-2013 from National Surveillance Network, consumption data from Chinese National Nutrition and Health Survey in 2002, and number of population from China Statistical Yearbook in 2011. Results Ready-to-eat raw fish has the highest per serving risk of listeriosis among all the selected food categories, and loose packaged meat products also have very high risk. Ready-to-eat bean curd skin has the highest per annum risk among all the food categories. For same category of meat products, risk of listeriosis for loose packaged products was 4-10 times higher than the prepackaged ones.Conclusion Ready-to-eat raw fish and loose packaged meat products have relatively higher per serving risk of listeriosis for sensitive population and ready-to-eat bean curd skin has relatively higher per annum risk of listeriosis.

Abstract:To assess combined dietary exposure and health risk of anti-androgenic phthalate acid esters(PAEs) , that is,DEHP,DBP and BBP among Chinese adult liquor drinkers, including general drinkers population, male and female adults aged 18-59 years old as well as elderly male and female aged 60 and above.Methods Food samples were collected during 2011-2013 and categorized into 24 food groups which covered major foods in China. Food consumption data were taken from China national nutrition and health survey performed in 2002. Mean concentrations of individual PAEs were combined with individual food consumption data to estimate dietary exposure of DEHP, DBP and BBP respectively. Then, hazard index approach was used to calculate the cumulative risk of anti-androgenic phthalate acid esters. Results It was found that mean and high consumption (P97.5) for the general adult liquor drinkers as well as 4 age-gender groups were well below the corresponding tolerable daily intake (TDI) of DEHP, DBP and BBP respectively. Further analys is showed that there were 18 individuals having intake higher than the TDI of DBP, accounting for 0.64 percentage of Chinese adult liquor drinkers. As for combined exposure for DEHP, DBP and BBP, mean and high consumption consumer hazard index (P97.5) for the general adult liquor drinkers as well as 4 age-gender groups were well below 1. Further analysis showed that there were 22 individuals having hazard index higher than 1, accounting for 0.79 percentage of Chinese adult liquor drinkers.Conclusion It suggested that cumulative risk to anti-androgenic PAEs (DEHP, DBP and BBP) among general Chinese adult liquor drinkers population is low and do not pose an imminent health concern. A greater health risk exists for 22 adult liquor drinkers for whom moderate alcohol consumption is advised.

Abstract:As new media developed, food scandals exposed by Internet cause consumers' concern and influence consumers' behaviors and emotional reactions. Therefore, the study of consumers' risk perception is instructive to improve the risk communication efficiency.Methods This paper was based on the survey data from 1 083 questionnaires of six cities, and showed the result of statistical and econometric analysis. Results According to the ranking of consumers' concern, diet hazard followed subsequently environment pollution, which was considered to be the greatest risk. In general, consumers' risk perceptions were above the average level. The information from network got high attention from consumers, and nearly 80% consumers thought such information was believable. Government and its portals, as the main information dissemination, got highest trust from consumers. Based on the structure model analysis, four latent variables had significant correlation with the route of risk perception. By the regression analysis, it was demonstrated that age, education level, and family income per month had significantly negative impact to consumers' risk perception.Conclusion It is important to utilize big data for exploring consumers' food safety risk perception at the national level, along with establishing interactive risk communication among consumers and government. Such researches are able to promote the positive role of network media in food safety co-regulation.

Abstract:Find out the reason of food poisoning and take effective control measures to prevent similar incidents.Methods Use descriptive epidemiological curves to deduce suspicious meal, identify suspicious meal and suspicious foods from case-control study, analyze the dose-response relation between food and disease, and collect related samples of for laboratory test. Results The reason of the food poisoning was the dinner on August 15th. There was dose-response relation between fried mackerel consumption and morbidity (trend chi-square test P<0.05). The histamine content of the remaining fried mackerel exceeded the national standards.Conclusion Consumption of fried mackerel was the main reason of histamine food poisoning.

Abstract:Obesity has emerged as an important public health problem in recent several decades, and been regarded as an important factor of female infertility as well. Many researchers focused on the impact of obesity on follicle and oocyte structure and function, because successful development and normal structure of ovarian follicle and oocyte were the basis of healthy female reproduction. Current evidence has indicated that obesity and its concomitant events impair the number and structure of oocyte and follicle in ovary, as well as its maturation development. It is recognized that obesity may induce above impairment through the disorders in oxidative stress and endoplasmic reticulum stress, hormone and adipokines. However, the specific mechanism remained unclear. Future study is needed to elucidate the pathway through which obesity impairs the survival and development of ovarian follicles and oocytes, and propose reasonable measures against the impairment.

Abstract:Obesity has become one of the important chronic disease which threatens the human health, and gut microbiota play an important role in the occurrence and development of obesity. Proposed mechanisms for the role of gut microbiota include the increase of energy harvest from the diet, regulation synthesis and storage of fat, induction chronic low-grade inflammation, eventually leading to obesity and subsequent metabolism disorders. Elucidating the mechanism of the intestinal flora in obesity may provide new targets for the prevention and treatment of obesity.