Objective To develop and compare the methods for determining the carrier status in the 18 deleted families of Duchenne and Becker muscular dystrophy. Methods Deletion analysis of the probands was performed by multiplex polymerase chain reaction (PCR) to amplify 9 dystrophin exons described by Chamberlain. Polymorphism linkage analysis was made on DNA with PCR amplification using primers of intragenic short tandem repeat sequences (STR44, STR45, STR49 and STR50), primers of 5′ end (5′DYS II) and primers of 3′end (MZ18, MZ19) in the members of the families. Gene dosage analysis was performed and DQ value was calculated. Results Both of deletions of exons and STR allelic fragments adjacent to the deleted exons were determined in the probands. STR allelic fragments of 6 pairs of heterozygotes, 2 pairs of homozygotes and 11 hemizygotes were detected at those loci in all of the female relatives. 13 female relatives in deleted families were assayed with gene dosage analysis. In 9 /13 female relatives DQ value was in the range of single copy and carrier status was ascertained.Conclusion Repeat sequence polymorphism as well as gene dosage analysis can potentially be used in carrier detection in the deleted families of Duchenne and Becker muscular dystrophy.

OBJECTIVETo assess dietary exposure of diethylhexyl phthalate(DEHP) among Chinese population, including general population, children aged 2-6 years, adolescent aged 7-12, young people aged 13-17, adults aged 18-59 years old as well as older people aged 60 and above and its health risk.

METHODSA total of 6 650 food samples were collected during 2011 to 2013 from 140 local markets of 14 provinces in China, which covered major foods in China. Samples were detected by GC-MS and categorized into 22 food groups. Food consumption data were taken from China National Nutrition and Health Survey performed in 2002 including 68 959 subjects. Mean concentrations of DEHP in food were combined with individual food consumption data to estimate dietary exposure, and food contributors to dietary DEHP intake were also calculated. Then, the exposure was compared with the tolerable daily intake (TDI, 50 µg·kg(-1)-d(-1)) of DEHP.

RESULTSDEHP level in foods (n = 6 650) was in the range of not detected to 43.80 mg/kg. Mean dietary intakes of DEHP in general population was 2.07 (95% CI: 0.06-4.09) µg·kg(-1)·d(-1), accounting for 4.14 percent of TDI (50 µg·kg(-1)·d(-1)). Mean dietary intake for population aged 2-6, 7-12, 13-17, 18-59 as well as elderly aged 60 and above were 3.92 (95% CI: 0.83-7.01), 3.02 (95% CI: 0.69-5.36), 2.17 (95% CI: 0.54-3.81), 1.83 (95% CI: 0.46-3.21) and 1.66 (95% CI: 0.38-2.94) µg·kg(-1)·d(-1) respectively. The 97.5 percentile intakes in the general populations was 4.73 µg·kg(-1)·d(-1), accounting for 9.46% of TDI. Main food sources of DEHP were rice (28.4% (0.59/2.07)), melon solanaceous vegetables (14.7% (0.30/2.07)) and flour (13.2% (0.27/2.07)) for the general population.

CONCLUSIONThe results suggested that dietary exposure to DEHP among Chinese population was lower than tolerable daily intake of DEHP and there were no health concerns based on generally accepted exposure limits. Rice, melon solanaceous vegetables and flour were main food contributors of DEHP dietary intake for Chinese populations.

Adolescent ; Adult ; Aged ; Asian Continental Ancestry Group ; Child ; Child, Preschool ; China ; Diet ; Diet Surveys ; Diethylhexyl Phthalate ; Flour ; Food ; Food Contamination ; Gas Chromatography-Mass Spectrometry ; Humans ; Middle Aged ; Oryza ; Risk Assessment ; Vegetables

BACKGROUND: China has the world's largest tea plantation area in the world. To sustain high yields of the tea, multiple pesticides are used on tea crops to control pests. Organophosphorus (OP) pesticides are among the most widely used types of agricultural pesticides in China. As tea is a significant potential source of exposure to pesticide residues, the public concern has increased in relation to pesticide residues found in tea in China. The aim of the study was to estimate cumulative dietary exposure to OP residues from tea infusion for Chinese tea consumers to determine whether exposure to OP residues from tea infusion is a cause of health concern for tea consumers in China. METHODS: OP residue data were obtained from the China National Monitoring Program on Food Safety (2013-2014), encompassing 1687 tea samples from 12 provinces. Tea consumption data were obtained from the China National Nutrient and Health Survey (2002), comprising 506 tea consumers aged 15-82 years. The transfer rates of residues from tea leaves into tea infusions were obtained from the literature. The relative potency factor (RPF) approach was used to estimate acute cumulative exposure to 20 OP residues from tea infusion using methamidophos as the index compound. Dietary exposure was calculated in a probabilistic way. RESULTS: For tea consumers, the mean and the 99.9th percentile (P99.9) of cumulative dietary exposure to OP residues from tea infusion equalled 0.08 and 1.08 μg/kg bw/d. When compared with the acute reference dose (ARfD), 10 μg/kg bw/d for methamidophos, this accounts for 0.8 and 10.8% of the ARfD. CONCLUSIONS Even when considering OP residues from vegetables, fruits and other foods, there are no health concerns based on acute dietary exposure to OP residues from tea infusion. However, it is necessary to strengthen the management of the OP pesticides used on tea in China to reduce the risk of chronic dietary exposure to OPs from tea infusion.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; China ; Dietary Exposure ; analysis ; Female ; Humans ; Male ; Middle Aged ; Organophosphorus Compounds ; analysis ; Pesticide Residues ; analysis ; Risk Assessment ; methods ; Tea ; chemistry ; Young Adult