The status and health risk assessment of dietary fipronil contamination among 20 provinces of China / 中华预防医学杂志

Objective@#To understand the status and health risk assessment of dietary fipronil contamination among 20 provinces of China.@*Methods@#A total of 13 kinds of dietary samples in Chinese total diet study include cereals, legumes, potatoes, meats, eggs, aquatics, dairies, vegetables, fruits, sugars, beverages and water, alcohols, condiments and their corresponding products. Among them, condiments were used in the preparation of 12 other sample categories; thus, the actual mixed dietary samples of each province covered 12 groups. A total of 240 mixed dietary samples were collected from 20 provinces in China from 2009 to 2013. After the sample extraction and cleanup, dietary samples were analyzed for the residues of fipronil and its metabolites to obtain the contamination levels of fipronil residues using liquid chromatography-high resolution mass spectrometry. The dietary intake of adult residents was estimated based on food consumption of general population of China.@*Results@#Among the 240 dietary samples, the detection rate of fipronil was 10.4% (25 samples), and the detection rates of fipronil metabolites, i.e. fipronil desulfinyl, fipronil sulfone and fipronil sulfide were 20.4% (49 samples), 40.0% (96 samples) and 8.8% (21 samples), respectively. According to the dietary exposure analysis, the average lower and upper dietary exposure levels of fipronil residues in adult residents of China were 11.34 and 12.35 ng·kg-1·d-1, accounting for 5.7% and 6.2% of acceptable daily intake (ADI), respectively. The highest adult dietary intake of fipronil residues was found in Hunan province, with a value of 72.98 ng·kg-1·d-1, accounting for 36.5% of ADI. Vegetables were the main dietary source of fipronil residues, which contributed to 71.0% of the total intake dose.@*Conclusion@#Fipronil residues were detected in varying degrees in dietary samples, yet the health risk caused by the dietary intake of adult residents among 20 provinces of China is low.

Effect of the ratio of living related donor renal volume to recipient body surface area on early function of transplanted kidney / 器官移植

Objective To investigate the relationship between the ratio of living related donor renal volume (RV) to recipient body surface area (BSA) (RV/BSA) and early postoperative function of transplanted kidney. Methods Clinical data of 120 pairs of donors and recipients undergoing living related renal transplantation were retrospectively analyzed. According to the RV/BSA ratio, the recipients were divided into group A (RV/BSA<65.33 mL/m2), group B (RV/BSA 65.33~76.49 mL/m2), group C (RV/BSA 76.50~96.96 mL/m2) and group D (RV/BSA > 96.96 mL/m2). The postoperative estimated glomerular filtration rate (eGFR) of recipients was compared among 4 groups. The correlation between the RV/BSA and eGFR of recipients at postoperative 6 and 12 months was analyzed. Results The eGFR at postoperative 6 month in group A was significantly lower than that in groups B, C and D (t=2.313, 2.947, 5.903; all P<0.05). The eGFR at postoperative 12 month in group A was also significantly lower than that in groups B, C and D (t=2.189, 2.433, 2.909;all P<0.05). The RV/BSA was significantly correlated with the eGFR of recipients at postoperative 6 and 12 months (all P<0.05).Conclusions RV/BSA is intimately correlated with the early function of transplanted kidney after living related renal transplantation.

Analysis of fipronil and metabolites residues distrubution in eggs / 中华预防医学杂志

Objective@#To compare the residual distribution of fipronil and its metabolites in white and yellow egg, and to analyze the residual changes of fipronil and its metabolites in raw and cooked samples, regarding the risk assessment of fipronil and its metabolites via consuming egg for different age groups.@*Methods@#The white egg and yellow egg were isolated from 10 egg samples containing fipronil residues. Samples were extracted with acetonitrile and purified, and determined by liquid chromatography-high resolution mass spectrometry. The chromatographic analysis was performed on a BEH C18 column with 0.1% acetic acid and acetonitrile as mobile phase with gradient elution, and external standard calibration was used for quantification. The negative ion acquisition mode was applied and quantitative analysis was carried out by using Full Scan/ddms2 model.@*Results@#The results showed that fipronil sulfone was the main residue detected in eggs; The content of fipronil sulfone in white egg was between 2.5 and 59.9 μg/kg, the median was 16.1 μg/kg; and the content of fipronil sulfone in yellow egg ranged from 81.5 and 1 526.0 μg/kg, with a median of 390.0 μg/kg. The ratio of fipronil sulfone in yellow egg to white egg ranged from 8.0 and 14.6. Compared with that observed in fresh egg, after heating or cooking, the content ratio of fipronil sulfone residue between cooked samples and raw samples from yellow egg was between 0.80 and 0.96, the median was 0.90; and the ratio from white egg ranged from 0.65 to 1.06, the median was 0.83. The conversion coefficient of fipronil sulfone (f) between white egg and yellow egg was 3.1.@*Conclusion@#Yellow egg is a major intake source of fipronil and metabolites residues, and there is no obvious change for fipronil sulfone residue in eggs after heating or cooking. The conversion coefficient of fipronil sulfone (f) between white egg and yellow egg lays the foundation for assessing the health risks of fipronil and metabolites residues through yellow egg intake in special population.

The contamination and dietary exposure analysis for seven mycotoxins in the Fifth Chinese Total Diet Study / 中华预防医学杂志

Objective@#To investigate the contamination levels and dietary intakes of seven mycotoxins in Chinese diets.@*Methods@#In Chinese Total Diet Study, food aggregation was based on the food consumption of local residents, thus generating the sampling scheme. According to the sampling scheme, the food items were sampled at three survey points in each province and then mixed in the same proportion. The mixed dietary samples were prepared after being cooked and processed. The samples comprised of 13 categories of food: cereals, beans, potatoes, meat, eggs, aquatic products, milk, vegetables, fruits, saccharides, beverages and drinking water, alcohol, and condiments. Condiments were used in cooking, so there were in total 12 varieties of samples for determination. Altogether, the study included 240 mixed dietary samples from 20 provinces with 12 varieties. The contamination levels of the seven mycotoxins, including sterigmatocystin (SMC), citrinin (CIT), cyclopiazonic acid (CPA), moniliformin (MON), gliotoxin (GLIO), mycophenolateacid (MPA) and verruculogen (Verru), were analyzed by UPLC-MS/MS method, and dietary intakes of residents were estimated as well.@*Results@#Among the detected seven mycotoxins, MPA,GLIO and Verru were not detected. The content range of CPA in beans was 0.47-1.57 μg/kg and in alcohol was 0.19-2.26 μg/kg, and the detection rate of CPA was 7.1% (17/240). The content of SMC in aquatic products of Guangxi, in saccharides of Beijing, and in beverages of Liaoning was 2.88 μg/kg, 0.01 μg/kg, and 0.53 μg/kg, respectively. The content range of SMC in aquatic products was 0.70-1.76 μg/kg, and the detection rate was 2.9% (7/240). In addition, the content of CIT in fruit of Sichuan was 5.31 μg/kg, and the content of MON in milk of Jilin was 3.60 μg/kg. According to the dietary exposure analysis, the exposure levels of the seven mycotoxins in China's general population were low. MPA, GLIO and Verru were not detected, and the exposure range of the other four mycotoxins were 0.000-8.132 (CIT), 0.000-27.448 (SMC), 0.000-3.026 (CPA), and 0.000-62.847 ng·kg-1·d-1 (MON), respectively.@*Conclusion@#In the detected seven mycotoxins, CPA, SMC, CIT and MON were detected only in the individual diet in some areas with a low dietary exposure level. However, the contamination level of CPA in alcohol merits attention.

Determination of perchlorate in food by ultra performance liquid chromatography-tandem mass spectrometry / 中国食品卫生杂志

Objective To establish a method for the determination of perchlorate in food by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS).Methods The perchlorate residue in spices and condiments was extracted with water,that in vegetables and fruits was extracted with acetonitrile-water (1∶ 1,V/V),and that in meat,poultry,eggs,milk and aquatic products was extracted with acetonitrile-water (2∶ 1,V/V).The supernatant was cleaned up with C18 SPE (3 ml,200 mg),and the detection was carried out by UPLC-MS/MS with internal standardmethod for quantification.Results The calibration curve was linear in the concentration range of 0.3-20.0 pg/L (R2 ≥0.999),the recovery was in the range of 82.6％-108.6％,the relative standard deviation (RSD) was in the range of 1.0％-9.9％,and the limit of detection was 2.0 μg/kg for milk,and 10.0 μg/kg for other food.Conclusion The method was simple,accurate and highly sensitive,and suitable for the determination of perchlorate in food.

Screening and confirmation of copper chlorophyll adulteration in olive oils / 中华预防医学杂志

<p><b>OBJECTIVE</b>To develop a qualitative screening method by high performance liquid chromatograph-photo-diode array (HPLC-PDA) and a confirmation method by ultra performance liquid chromatograph-quadrupole-time of flight mass spectrometry (UPLC-Qtof-MSMS) for Copper Chlorophyll in olive oils.</p><p><b>METHODS</b>Commercial liposoluble copper chlorophyll diluted by petroleum ether was purified and concentrated by sep-pak silica solid-phase extraction (SPE) cartridges, the injection was separated by symmetry shield RP18 column, and detected by the PDA at the wavelength 430 nm. The injection was separated by ACQUITY UPLC BEH (18)C and determined by UPLC-Qtof-MSMS in negative atmospheric pressure chemical ionization mode, then confirmed by the exact mass of parent ion and secondary fragment ion provided by the mass spectrum. Samples from supermarket were screened for Cu-pyropheophytin a by established method.</p><p><b>RESULTS</b>Cu-pyropheophytin a could be used for discrimination as indicative compound whether the olive oils were mixed with copper chlorophyll. 25 samples including olive oil, soybean oil and spirulina from supermarket were screened, Cu-pyropheophytin a was found in one type of olive oil.</p><p><b>CONCLUSION</b>This method could be used for screening and qualitative analysis of Copper Chlorophyll in olive oils for its accuracy , reliability and excellent specificity.</p>

Analysis of perfluoroalkyl substances and their precursors in eighteen market milk / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the level of perfluoroalkyl substances (PFASs) and their precursors in 18 market milk samples of China.</p><p><b>METHOD</b>The 18 milk samples were selected in 8 provinces of China, including Ningxia, Neimeng, Beijing, Tianjin, Hebei, Shanxi, Chongqing, and Guangdong. 8 PFASs and 11 PFAS precursors were measured by ultra-high performance liquid chromatography-tandem quadruple mass spectrometry (UPLC-MS/MS). The dietary exposure assessment was made.</p><p><b>RESULTS</b>Three PFASs were detected in milk samples which were PFOA, PFUdA, and PFOS. The numbers of detected samples were 5, 12, and 14, respectively. Their concentration ranges were < Limit of determination (LOD)-431.94 pg/ml, < LOD -15.95 pg/ml and < LOD -126.98 pg/ml, respectively. Three PFAS precursors were also found above the detection limits, namely, 4:2 FTS, 6:2 FTS, and 6:2 diPAP. Only one sample was detected 4:2 FTS at the concentration of 3.75 pg/ml. The detected samples of 6:2 FTS and 6:2 diPAP were 12 and 3. Their concentration ranges were < LOD -2.49 pg/ml and < LOD -24.56 pg/ml, respectively. The ranges estimated daily intake of PFOA and PFOS of the detected samples were 2.49 × 10⁻³-405.89 × 10⁻³ ng · kg⁻¹ · d⁻¹ and 36.10 × 10⁻³-119.32 × 10⁻³ ng · kg⁻¹ · d⁻¹.</p><p><b>CONCLUSION</b>Our results suggested that there were different contamination levels of PFASs and their precursors in the 18 market milk produced from different regions in china. The estimated daily intake of PFASs from the milk in our study were far below the tolerable daily intake set by European Union (PFOS: 150 ng · kg⁻¹ · d⁻¹, PFOA: 1 500 ng · kg⁻¹ · d⁻¹).</p>

Analysis of perfluoroalkyl substances precursors in human milk from 12 provinces of China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the level of perfluoroalkyl substances (PFASs) precursors in Chinese human milk samples.</p><p><b>METHODS</b>The human milk samples were collected during the performance of Stockholm convention on survey of human milk in China in 2007. Based on the geographical location and dietary habits, China was divided into the south area and north area which 6 provinces were chosen from each area and there were 12 provinces in all. In each province, one urban site and two rural sites were selected to collect 80-110 samples. Mothers were randomly selected in each site to collect their breast milk. There were 1 237 individual human milk samples in all. For each province, the individual samples from the urban areas and the rural areas were pooled separately resulting in 24 pooled human milk samples. 11 PFAS precursors were measured in pooled samples by ultra-high performance liquid chromatography-tandem quadruple mass spectrometry (UPLC-MS/MS). The dietary exposure assessment of newborns was made.</p><p><b>RESULTS</b>Three PFAS precursors were found above the detection limits, namely, 6:2 FTS, FHUEA, and 6:2 diPAP. Their concentration ranges were < Limit of determination (LOD) -47.46 pg/ml, < LOD -70.68 pg/ml and < LOD -35.08 pg/ml, respectively. The highest total PFAS precursor concentration 77.70 pg/ml was found in urban area samples from Shannxi Province. Rural area samples from Hubei had the lowest total PFAS precursor concentration, which was below the LOD. There were significant differences between rural and urban areas in many provinces, such as Shannxi (rural: 1.51 pg/ml; urban: 77.70 pg/ml), Shanghai (rural: 1.13 pg/ml; urban: 71.88 pg/ml), Jiangxi (rural: 65.39 pg/ml; urban: 0.55 pg/ml) and so on. The ranges estimated daily intake of 6:2 FTS, FHUEA and 6:2 diPAP of the samples from 12 provinces were 0.05-4.51, 1.13-6.72 and 1.15-3.34 ng · kg⁻¹ · d⁻¹.</p><p><b>CONCLUSION</b>The results suggested the human exposure of PFAS precursors in China and the potential health impact of postnatal exposure through breastfeeding to infants. The level of PFAS precursors showed differences in regions, rural and urban places.</p>

Development of gas chromatography-mass spectrometry for determination of fatty acid esters of chloropropanols in milk powder and the pollution level of infant formula / 中华预防医学杂志

<p><b>OBJECTIVE</b>To establish a method for determination of fatty acid esters of chloropropanols (chloropropanols esters) in milk powder by isotope dilution-gas chromatography-mass spectrometry (GC-MS), and to acquire the pollution level of chloropropanols esters in infant formula and evaluate the dietary exposure risk of chloropropanols esters in infant formula for infants.</p><p><b>METHODS</b>A total of 111 infant formula samples were collected from supermarkets in Beijing, and the infant formula with no chloropropanols esters detected was served as the blank sample. The samples were ultrasonically extracted with hexane, followed by ester-bond cleavage reaction with sodium methylate-methanol and purification by matrix solid-supported liquid-liquid extraction, then being derivatived with heptafluoro butyrylimidazol. After extracted by sodium chloride solution, the derivatives were determined by GC-MS. The concentration of chloropropanols esters were quantified using the deuterium chloropropanols esters as the internal standards. The accuracy of the method was assessed by the recoveries of the blank spiked samples, and the relative standard deviations (RSD) of the recoveries represent the precision of the method. The contamination level of chloropropanols esters and the intake amount of the infant formula of the 6-month infant were used to estimate the dietary exposure assessment, and x (95% CI) and P97.5 of the contamination level of chloropropanols esters were used to represent the average dietary exposure and the high-end dietary exposure.</p><p><b>RESULTS</b>The satisfied linear correlations in the range of 0.010-0.800 mg/L was acquired for 3-MCPD esters, 2-MCPD esters, 1,3-DCP esters and 2,3-DCP esters with coefficient correlations of 0.999 9, 0.999 8, 0.999 5 and 0.999 6, respectively. The limits of detection (LOD) and the limits of quantitation (LOQ) for 3-MCPD esters, 2-MCPD esters, 1,3-DCP esters and 2,3-DCP esters were 0.005, 0.005, 0.015, 0.015 mg/kg, and 0.015, 0.015, 0.045, 0.045 mg/kg. The average recoveries of the four chloropropanols esters spiked at 0.025, 0.050 and 0.100 mg/kg in blank matrix were in a range from 80.3% to 111.9%, with relative standard deviations (RSD) less than 11.4%. Of the 111 infant formula samples, the detection rates and the contamination levels of 3-MCPD esters and 2-MCPD esters were 77.5% (86/111), 11.7% (13/111) with the contamination levels in the range of ND-0.230 mg/kg and ND-0.039 mg/kg, respectively, and χ (95% CI) and P97.5 of 3-MCPD esters and 2-MCPD esters were 0.020 (0.003-0.113) and 0.006 (0.005-0.025) mg/kg, 0.113 and 0.025 mg/kg, respectively. 1,3-DCP esters and 2,3-DCP esters were not detected in the 111 samples. x (95% CI) and P75 of the six-month old infants to 3-MCPD esters were 0.304 (0.038-1.735) and 1.735 µg · kg⁻¹ · d⁻¹, respectively, which accounted for 15.2% and 86.7% of the PMTDI (2 µg · kg⁻¹ · d⁻¹) of 3-MCPD.</p><p><b>CONCLUSION</b>This GC-MS method was accurate and rugged for the determination of chloropropanols esters in milk powder. Based on the exposure assessment results, the health risk of chloropropanols esters for infants caused by the intake of infant formula was acceptable.</p>

Long-term effect of cadmium exposure on residents' renal dysfunction: An epidemiologic study / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study long-term effect on renal function exposed to environmental cadmium.</p><p><b>METHODS</b>Stratified random sampling and cluster sampling method of epidemiological investigations were carried out in northern Guangdong province between April, 2011 and August, 2012. A total of 167 residents who lived in high cadmium exposure area for more than 15 years, aged above 40 were selected in exposed group. Moreover, A total of 145 residents who had similar living and economic conditions and lived in local for more than 15 years, aged above 40 were selected in control group. We used health questionnaires and medical examinations in order to acquire their health status. Home-harvested rice and vegetables were collected using quartering method for detection of cadmium level. Urine specimens of residents were collected for detection of cadmium level and creatinine as well as renal dysfunction biomarkers, namely, N-acetyl-beta-D-glucosamidase (NAG), β2-microglobulin (β2-MG), and retinol binding protein(RBP), respectively. The analysis of spearman rank correlation and multiple regression were used to investigate the relationships between age, urinary cadmium levels and renal injury biomarkers.</p><p><b>RESULTS</b>The cadmium levels in rice and vegetables of exposed group were 0.75 and 0.10 mg/kg, both were significantly higher than 0.07 and 0.01 mg/kg in the control group (Z values were -6.32 and -7.84, all P values < 0.001). The urinary cadmium level of exposed group was 8.29 µg/g · cr, which was higher than that of the control group 2.03 µg/g · cr with significant difference (Z value was -11.39, P < 0.001). After stratified the total population by age, the urinary cadmium level in 40-49 years, 50-59 years and ≥ 60 years subgroups were 7.22, 8.71, and 13.10 µg/g · cr, which both were significantly higher than 1.80, 2.04, and 2.05 µg/g · cr in the control group (Z values were -5.22, -7.41, and -7.14, all P values < 0.001). After stratified the total population by gender, the urinary cadmium level of male and female were 5.12 and 12.36 µg/g · cr, which both were significantly higher than 1.79 and 2.16 µg/g · cr in the control group (Z values were -7.68 and -9.03, all P values < 0.001). Comparing the differences of renal dysfunction biomarkers (NAG, β2-MG, RBP) between two groups. The level of urinary β2-MG and RBP of exposed group were 0.21 and 0.04 µg/g · cr, which were higher than 0.05 and 0.00 µg/g · cr of the control group with significant difference (Z value was -7.08 and -9.65, all P values < 0.001). Pearson correlation analysis showed that NAG, β2-MG and RBP were positively correlated with urinary cadmium and age, the correlation coefficients were 0.57, 0.49, 0.21 and 0.22, 0.26, 0.23 respectively (all P values < 0.001). After adjusting the effect of age, it was appeared that urinary cadmium levels contributed most to the alteration of NAG, β2-MG and RBP, the standardized regression coefficients were 0.57, 0.49 and 0.20 (all P values < 0.001), and suggested that the cadmium body burden was one of the most important factors for renal dysfunction.</p><p><b>CONCLUSION</b>Residents, who had cadmium contaminated rice and vegetables for a long time, would take the risk of increasing body burden of cadmium and urinary early biomarkers of renal tubular injury that referred to occurrence of renal dysfunction.</p>

CD62pUsing Light Transmission Aggregometry and Flow Cytometry to Examine the Effect of Clopidogrel / 现代检验医学杂志

Objective To detect clopidogrel effect with light transmission aggregometry (LTA)and flow cytometry (FC). Methods ①Venous blood samples were taken from 71 inpatient with acute corotary syndrome (ACS)in PLA General Hos-pital,including unstable anqina,ST segment elevation myocardial infarction and non ST segment elevation myocardial infarc-tion (46 males,25 females)by random number table from June 2011 to March 2012,whose average age was 69(57~92).②All of them were served 160 mg aspirin and 300 mg clopidogrel after they were in hospital in the beginning,and then served with 75 mg/d clopidogrel for 6 months.On some day,firstly,they were required withdrawing drug for 10 days,and then ve-nous blood samples were separately taken from them before their served-clopidogrel again and their severd-clopidogrel 2 hours later.③The samples were assayed with LTA and FC simultaneously and the platelet aggregation rates before served-clopidogrel (ADPLTA-before serving ),platelet aggregation rates after served-clopidogrel (ADPLTA-after serving ),inhibition rates (ADPLTA-INDU ),PAC-1 activity percentage before served-clopidogrel (PAC-1 before serving ),PAC-1 activity percentage after served-clopidogrel (PAC-1 after serving ),inhibition rates (PAC-1 INHI ),CD62p activity percentage before served-clopidogrel (CD62pbefore serving ),CD62pactivity percentage after served-clopidogrel (CD62pafter serving ),inhibition rates (CD62pINHI )weregotten.All volunteers were signed informed consents and the experiment was approved by the hospital ethics committee.Re-sults ①The paired samples t-test was (t=-2.082,P =0.041)between ADPLTA-before serving (0%~97%)and ADPLTA-after serving (12%~97%),the paired samples t-test was (t = 3.663,P < 0.01)between PAC-1 before serving (15.1% ~ 78.9%)and PAC-1 after serving (14.5% ~ 78.3%);the paired samples t-test was (t = 2.082 and P = 0.041)between CD62pbefore serving (1.5% ~80.8%)and CD62pafter serving (1.4%~41.4%).②The pearson coeffcient correlation results were:ADPLTA-INDU (0%~28.2%) and PAC-1 INHI (0.6%~ 9.1%)(r = 0.297,P = 0.012);ADPLTA-INDU (0% ~ 28.2%)and CD62pINHI (0.1% ~ 48.5%)(r =0.220,P =0.065);PAC-1 INHI (0.6%~9.1%)and CD62pINHI (0.1%~48.5%)(r=0.736,P <0.001).Conclusion Because the correlation was bad between the inhibition rates of clopidogrel detected by FC and them by LTA,FC didn’t apply to clin-ical routine examination of the platelet aggregation.But it could be used to scientific researchs and auxiliary confirmation of routine examination results.

The application of UPLC-MS/MS to detect precursors of perfluorooctanoic acid and perfluoroalkyl carboxylatesin serum / 中华预防医学杂志

<p><b>OBJECTIVE</b>We established a method of UPLC-MS/MS that was to detect fifteen precursors of perfluoroalkyl sulfonates (PFSA) and perfluoroalkyl carboxylates (PFCA) in serum.</p><p><b>METHODS</b>Briefly, TBAS solution was added to sera, then the mixed solution was extracted with aliquots of MTBE. The MTBE aliquots were combined, evaporated to dryness under nitrogen, and reconsituted in 0.25 ml of methanol and water (1:1). Then the reconstituted solution through 0.2 µm nylon syringe filter was collected. Chromatographic separation was performed using a Waters ACQUITY (TM) BEH ¹⁸C column (50 mm × 2.1 mm × 1.7 mm). Analyte quantitation was performed in the negative electrospray ionization mode and multiple reaction monitoring (MRM).</p><p><b>RESULTS</b>Three target substances, 6: 6PFPi, 6: 8PFPi, 8: 8PFPi, were externally confirmed by standard addition. Rates of recovery for these three chemicals were from 41.01% to 112.13% in two standard levels. And the relative standard deviations (RSD) were lower than 11.63% and higher than 1.80%. The other twelve substances were quantified with internal standard. Moreover in two standard levels, rate of recovery for these chemicals ranged from 70.25% to 127.51%. And RSD were more than 1.23% and less than 15.45%. And the corresponding limit of detection (LOD) and limit of quantitation (LOQ) for all target substances were 0.1-5.0 pg/ml and 0.2-10.0 pg/ml. Then we detected these target substances in ten different human serum samples. The levels of few substances were higher than LOD. And the ranges of FOSA-M, N-EtFOSA-M, N-MeFOSAA, N-EtFOSAA were respectively < LOD-0.94 pg/ml, < LOD-10.08 pg/ml, < LOD-6.74 pg/ml, < LOD-1.04 pg/ml.</p><p><b>CONCLUSION</b>The method, with high sensitivity and accuracy, could meet the actual testing requirements.</p>

Ocuurence of organophosphorus pesticides in animal foods and their diet exposure assessment / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the levels of organophosphorus pesticides (OPPs) in animal foods and to assess the diet exposure risk of OPPs to Chinese population.</p><p><b>METHODS</b>115 samples, including pork, beef, mutton, chicken, fish, eggs, and milk were collected from 13 provinces in China, were analyzed by dual gas chromatography-dual pulsed flame photometry (GC-PFPD) for the contamination of 58 organophosphorus pesticide residues including their metabolites. The cumulative exposure assessment and high-end exposure assessment were used to assess the diet exposure risk of OPPs to Chineses population.</p><p><b>RESULTS</b>The contamination levels of OPPs in animal foods were in the range of not detected (ND)-0.343 mg/kg, and the total detection rate was 37.4% (43/115). OPPs were frequently detected in samples of milk, fish and pork compared with other animal foods with the detection rate of 12/19, 9/16 and 7/16, respectively. The cumulative exposure amount of 10 OPPs to Chinese population was 0.12 µg×kg(-1)·d(-1), which accounted for 7.29% of the ADI.</p><p><b>CONCLUSION</b>The residue levels of OPPs were low in animal food in the surveyed areas in China with some banned individual OPPs, such as methamidophos and monocrotophos, were detected. The dietary exposure risk of OPPs raised by the intake of animal foods in surveyed areas of China was low.</p>

Nineteen cases of biliary ascariasis diagnosed and managed by endoscopic retrograde cholangiopancreatography / 中华传染病杂志

Objective To investigate the role of endoscopic retrograde cholangiopancreatography (ERCP) in the diagnosis and treatment of adult biliary ascariasis.Methods Clinical data of 19 cases of adult biliary ascariasis diagnosed and treated with ERCP during Jan 2005 to Dec 2012 were retrospectively analyzed.Results Among the 19 adult patients with biliary ascariasis,11 were male,and the mean age was (62.7± 10.8) years.Eight cases lived in the countryside,7 cases in the integration of urban and rural area,and 4 cases in urban area.All cases had histories of eating raw fruits and vegetables.Living worms were found in 9 cases.Four cases were complicated with common bile duct stones.Petrification of residual dead worms in the common bile duct was found in 10 cases.All ascariasis and residual bodies were removed successfully by ERCP.There were no postoperative complications except for 3 cases of hyperamylasemia.Conclusions Adult biliary ascariasis commonly occurs in the elderly,and is frequently complicated with common bile duct stones.ERCP is efficacious in treating biliary ascariasis.

Diagnostic value of double balloon endoscopy for gastrointestinal disease / 中华消化内镜杂志

ObjectiveTo study the diagnostic value of double balloon endoscopy (DBE) for gastrointestinal disease.MethodsClinical data of 53 patients with suspected intermediate gastrointestinal diseases who underwent DBE procedures were retrospectively analyzed for detection rate,complications and the incidence of adverse reactions.ResultsAll of 53 patients underwent successful DBE,Procedures were performed via mouth ( n =26),anus ( n =9 ) and the combined routes ( n =18 ).And definite diagnosis was made in 46 cases (86.79％),including upper gastrointestinal (above ligament of Treitz) disease in 3 cases (5.66％),intermediate gastrointestinal disease in 41 cases (77.36％ ) and lower gastrointestinal disease in 2 cases (3.77％).All 53 patients were tolerant to the operation and anesthesia.No severe complications like bleeding,perforation,intestinal torsion,mesenteric tear,pancreatitis or anesthetic accident occured.Several patients showed abdominal flatulence,transient abdominal pain.Some patients in oral route reported slight throat discomfort or slight nasal bleeding.Incarceration occurred in 1 case due to friction of endotracheal intubation and the silicone tube,which was released after deflation and removed out.2 patients showed mild diarrhea with low fever,and the symptoms were self-healing without special treatment in 48 h.ConclusionDBE is of high diagnostic value for gastrointestinal diseases with a high safety.

Particle-bound PCDD/Fs in the atmosphere of an electronic waste dismantling area in China / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>Particulate samples from the atmosphere in an electronic waste dismantling area were collected to investigate the levels and sources of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs).</p><p><b>METHODS</b>Particulate samples including total suspended particulates (TSP) and particulate matter <2.5 μm diameter (PM(2.5)) were collected on selected non-rainy days in summer (Jul 10-12, 2006) and winter (Jan 11-13, 2007) from Fengjiang (FJ), an electronic waste (e-waste) dismantling area in eastern China, and an adjacent area Luqiao (LQ). The samples were analyzed by isotope dilution - high resolution gas chromatography / high resolution mass spectrometry (HRGC/HRMS).</p><p><b>RESULTS</b>In FJ, the mean PCDD/F concentrations (mean TEQ values) were 280.6 pg Nm(-3) (3.432 pg WHO-TEQ Nm(-3)) for the TSP samples and 223.3 pg Nm(-3) (3.180 pg WHO-TEQ Nm(-3)) for the PM(2.5) samples. The total PCDD/F concentrations and TEQs in the PM(2.5) samples were about 66.8%-108.0% of the TSP samples, indicating that the fine particles contained higher levels of PCDD/Fs than coarse particles. The PCDD/F levels in FJ were much higher than those detected in common urban areas around the world, suggesting that the study area was heavily polluted by PCDD/Fs. Furthermore, the total average daily PCDD/F intake in FJ was estimated at 62.11 pg WHO-TEQ kg(-1)·day(-1) for adults and 110.11 pg WHO-TEQ kg(-1)·day(-1) for children, which greatly exceeds the WHO (1998) tolerable daily intake of 1-4 pg of WHO-TEQ kg(-1)·day(-1).</p><p><b>CONCLUSION</b>The PCDD/F homologues and congener profiles confirmed that the PCDD/Fs in FJ originated from crude e-waste recycling activities. The severe dioxin pollution present in FJ has also substantially influenced the adjacent area of LQ through atmospheric transport. Open burning of medical waste was another source of PCDD/Fs identified in LQ.</p>

Advances in functional studies of nonstructural proteins and development of antiviral agents for enterovirus 71 / 药学学报

Human enterovirus 71 (EV71) is one of the major etiological agents for the hand, foot, and month disease (HFMD) and is causing frequent, widespread occurrence in the mainland of China. The single positive-stranded RNA genome of EV71 is translated into a single polyprotein which is autocleavaged into structural and nonstructural proteins. The functions of many nonstructural proteins characterized in the life cycle of virus are potential targets for blocking viral replication. This article reviews the studies of the structures and functions of nonstructural proteins of EV71 and the anti-enterovirus 71 drugs targeting on these nonstructural proteins.

Endoscopic biliary stent drainage for obstructive jaundice due to hepatic portal metastatic carcinoma / 中华消化内镜杂志

Objective To investigate the clinical value of endoscopic biliary stent drainage for obstructive jaundice due to hepatic portal metastatic carcinoma. Methods Patients with obstructive jaundice arising from hepatic portal metastatic carcinoma were selected and treated with consent by plastic endoscopic bile duct stents since 2006. Success rate and survival were evaluated. A total of 38 patients with obstructive jaundice were treated and analyzed. Hepatic portal metastatic carcinoma included 13 cases of liver cancer, 3gallbladder carcinoma, 14 gastric carcinoma, 2 esophageal carcinoma, 1 ileum adenocarcinoma and 5 pancreatic carcinoma. Results Stents were successfully placed in all patients and jaundice rapidly subsided after the endoscopic procedure. Follow-up life span was 92-521 days, mean 264. 42 ± 104. 41 days. During follow-up, biliary stents were replaced in 5 patients in 3-14 months ( mean 8. 6 ± 4. 1 months) because of stent displacment in 1 case, biliary stone obstruction in 2 cases and carcinomatous obstruction in 2 others.Conclusion For patients with obstructive jaundice arising from hepatic portal metastatic carcinoma, endoscopic biliary stent drainage is effective and can prolong life span to some degree.

Endoscopic palliative treatment for advanced pancreatic cancer / 中华消化内镜杂志

Objective To investigate the therapeutic effects of endoscopy for palliative treatment of advanced pancreatic cancer. Methods A typical case of un-resectable advanced pancreatic cancer was reviewed, who underwent obstruction of upper gastrointestinal tract, obstructive jaundice and alimentary tract hemorrhage subsequently. The patient received multiple placement of intestinal tract stents, common bile duct stents and hemostatic treatment endoscopically. Because of the obstruction of upper gastrointestinal tract, jejunalostomy and retrograde endoscopy through the orificium fistulae were performed to place bile duct stents. Results The patient survived for 10 months with good life quality after diagnosis, obstruction of upper gastrointestinal tract, obstructive jaundice and alimentary tract hemorrhage were cured and didn't recur till death.Conclusion Therapeutic endoscopy, safe and effective, is the first choice for advanced pancreatic cancer complicated with obstruction of digestive tract (including gastrointestinal tract, bile duct and pancreatic duct).

Stress analysis of prosthodontics by finite element method / 生物医学工程学杂志

Finite element stress analysis has been widely used in stomatology. In this article, we summarized the stress distributions of all-ceramic crowns, post crowns, fixed partial dentures and implant support fixed dentures; and with the use of finite element method, we investigated the stress levels of the periodontal ligament of abutment. The results showed: the tensile stress and compressive stress concentrated at the cervical margin of all-ceramic crown and post crown; the stress at the surface of the crown was the highest; the stress concentration exhibited at the connector of fixed parital denture, the molar was an ideal abutment tooth for the fixed bridge; the largest stress appeared around the neck of the implant abutment. These results have provided a theoretical basis for clinical dentistry in terms of restoration design and manufacture. It is suggested that clinical dentists should be careful to avoid the horizontal laoding applied on the prostheses so as to improve the resistance of abutment tooth to fracture.