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Wu P.,U.S. Center for Disease Control and Prevention | Cai C.,Zhejiang University of Science and Technology | Yang D.,National Center for Food Safety Risk Assessment | Zhang Y.,Zhejiang University of Science and Technology | And 2 more authors.
Journal of Separation Science | Year: 2015

A gradient clean-up method for the quantification of five kinds of banned drugs (two hormones, two sedatives, and one chloramphenicol) in milk powder was developed. We used the combination of solid-phase extraction purification with gas chromatography and mass spectrometry. Milk powder was initially hydrolyzed by β-glucuronidase/arylsulfatase, and then the hydrolyzed solution was concentrated and purified using a C8 and cation resin solid-phase extraction column. To isolate hormones and chloramphenicol drugs, products from the previous step were diluted with methanol and further purified using a silica and diatomite solid-phase extraction column. After derivatization, the drugs were analyzed by gas chromatography with mass spectrometry, and the hydrolyzed solution was diluted with 5% ammoniated methanol to purify sedatives before gas chromatography with mass spectrometry analysis. Results showed that after adding the banned drugs at concentrations of 0.3-10.0 μg/kg, the average recovery range was 78.2-97.3% with relative standard deviations of 5.3-12.5%. The limit of quantification of the banned drugs (S/N ≥ 10) was 0.3-5.0 μg/kg, whereas the limit of detection (S/N ≥ 3) was 0.1-2.0 μg/kg. The solid-phase extraction gradient purification system was simple, rapid, and accurate, and could satisfy the detection requirements of hormone, sedatives, and chloramphenicol drugs when used together with gas chromatography and mass spectrometry. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Yan H.,Food Laboratory of Beijing Inspection and Quarantine Testing Center | Liu X.,Food Laboratory of Beijing Inspection and Quarantine Testing Center | Cui F.,Food Laboratory of Beijing Inspection and Quarantine Testing Center | Yun H.,Food Laboratory of Beijing Inspection and Quarantine Testing Center | And 4 more authors.
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2013

A novel sample pretreatment method was developed for the quantitative determination of amantadine and rimantadine in chicken muscle tissues by ultra high performance liquid chromatography coupled with high resolution LTQ Orbitrap mass spectrometry (UHPLC-LTQ Orbitrap MS). The samples were pretreated by modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method, using acetonitrile (1% acetic acid, v/v) as extraction solution and C18 sorbent for clean-up. The separation was carried out on a Waters ACQUITY UPLC HSS T3 column (150mm×2.1mm, 1.8μm particle), using a mobile phase of acetonitrile and 0.1% aqueous formic acid solution. LTQ Orbitrap MS with resolving power of 60000 was applied for analysis of the samples. Amantadine and rimantadine were identified from their accurate mass (within 5ppm) and retention times from the acquired full-scan chromatogram and quantified by their peak areas. The linear range for the determination of the analytes was 1-100μg/kg. Limits of detection (LODs) for amantadine and rimantadine were 1.02μg/kg and 0.67μg/kg, respectively. The intra- and inter-day accuracy ranged from 87.5% to 102.4%, and 82.5% to 105.8% for amantadine, and 95.3% to 97.4%, and 89.4% to 93.2% for rimantadine, respectively. The precision of intra- and inter-day was between 3.9-6.3% and 5.95-13.9% for amantadine, 6.0-7.45% and 7.8-12.4% for rimantadine, respectively. Finally, the method was applied for the determination of these antiviral agents in routine samples, and amantadine residue was detected in some cases. © 2013 Elsevier B.V. Source

Huang X.,U.S. Center for Disease Control and Prevention | Huang X.,Sun Yat Sen University | Li Y.,U.S. Center for Disease Control and Prevention | Huang Q.,U.S. Center for Disease Control and Prevention | And 9 more authors.
BMC Public Health | Year: 2013

Background: Haff disease is unexplained rhabdomyolysis caused by consumption of fishery products in the previous 24 h. It was first identified in Europe in 1924 but the condition is extremely rare in China. Here we describe a past outbreak of acute food borne muscle poisoning that occurred in Guangdong Province (South China) in 2009. Methods. The first full outbreak of Haff disease reported in Jiangsu Province (East China) in 2010, indicated that the incidence of the disease may be increasing in China. We, therefore first retrospectively reviewed epidemiologic, trace-back, environmental studies, and laboratory analyses, including oral toxicity testing to ascertain risk and chemical analysis to identify toxin(s), from the 2009 Guangdong outbreak. Then we compared data from the 2009 outbreak with data from all other Haff disease outbreaks that were available. Results: Clinical symptoms and laboratory findings indicated that the 2009 Guangdong outbreak disease was consistent with rhabdomyolysis. Epidemiologic, trace-back, environmental studies and laboratory analyses implied that the disease was caused by freshwater Pomfrets consumed prior to the onset of symptoms. We also identified common factors between the 2009 Guangdong outbreak and previous Haff disease outbreaks reported around the world, while as with other similar outbreaks, the exact etiological factor(s) of the disease remains unknown. Conclusions: The 2009 Guangdong outbreak of 'muscle poisoning' was retrospectively identified as an outbreak of Haff disease. This comprised the highest number of cases reported in China thus far. Food borne diseases emerging in this unusual form and the irregular pattern of outbreaks present an ongoing public health risk, highlighting the need for improved surveillance and diagnostic methodology. © 2013 Huang et al.; licensee BioMed Central Ltd. Source

Yang H.,National Center for Food Safety Risk Assessment | Jia X.,National Center for Food Safety Risk Assessment
Zhonghua yu fang yi xue za zhi [Chinese journal of preventive medicine] | Year: 2015

Threshold of toxicological concern (TTC) is a scientific and practical method for the food safety risk assessment of chemicals, and also an useful tool for the identification and screening of chemicals with risk assessment priority. However, there were still controversial opinions concerning the application of this method, which was established to provide risk characterization on the bases of chemical structures whereas in the lack of conventional toxicological data. Here, we reviewed the principles, critical factors, and recent progress in the application of TTC method, to explore and summarize the critical aspects that need particular considerations in the risk assessment of chemicals. Source

Ma N.,National Center for Food Safety Risk Assessment | Wang X.,National Center for Food Safety Risk Assessment | Gao P.,National Center for Food Safety Risk Assessment | Xu H.,National Center for Food Safety Risk Assessment
Wei sheng yan jiu = Journal of hygiene research | Year: 2013

OBJECTIVE: To explore the effects of diisobutyl phthalate (DiBP) on the cAMP/PKA-CREB signaling pathway of hippocampus in mice.METHODS: Accommodating 30 KunMing mice to the animal house for 3 days, then dividing the mice into 5 groups according to their weights. That is, one control group and four experimental groups (I group, 50 mg/kg BW; II group, 250 mg/kg BW; Ill group, 500 mg/kg BW; IV group, 1000 mg/kg BW). The mice were fed with the corn oil in control group, and the other groups were fed with the related dose of DiBP mixture by gavages last for 8 weeks. At the end of experimental time, the mice were killed, and the tissue samples of hippocampus were taken immediately. The content of cAMP was determined by ELISA, and p-CREB, P-PKA C were measured by western blotting, while mRNA expressions including CREB, BDNF, c-fos and c-jun were checked by RT-PCR.RESULTS: The cAMP content and the p-PKA C protein of hippocampus in IV group was significantly less than control group (P<0.05) and compared with control group, the p-CREB protein of hippocampus in 1I group decreased (P<0.05), while the relative level of CREB, BDNF, c-fos and c-jun mRNA were down-regulated in all experimental groups.CONCLUSIONS: The abnormal changes of expression of the signal molecules composing the cAMP/PKA-CREB signaling pathway were observed in the hippocampus of DiBP exposure mice. This might be one of the possible mechanisms of DiBP induced cognitive impairment. Source

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