Division of Intramural Research, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina 27709, USA.
Epigenetic modifications, such as DNA methylation, due to in utero exposures may play a critical role in early programming for childhood and adult illness. Maternal smoking is a major risk factor for multiple adverse health outcomes in children, but the underlying mechanisms are unclear.
We investigated epigenome-wide methylation in cord blood of newborns in relation to maternal smoking during pregnancy.
We examined maternal plasma cotinine (an objective biomarker of smoking) measured during pregnancy in relation to DNA methylation at 473,844 CpG sites (CpGs) in 1,062 newborn cord blood samples from the Norwegian Mother and Child Cohort Study (MoBa) using the Infinium HumanMethylation450 BeadChip (450K).
We found differential DNA methylation at epigenome-wide statistical significance (p-value
We identified age-dependent post-translational modifications of skeletal muscle glycogen phosphorylase b (Ph-b), isolated from F1 hybrids of Fisher 344 x Brown Norway rats. Ph-b isolated from 34 months old rats showed a statistically significant decrease in specific activity compared to 6 months old animals: 13.8+/-0.7 vs. 20.6+/-0.8 U mg(-1) protein, respectively. Western blot analysis of the purified Ph-b with anti-3-NT antibodies revealed an age-dependent accumulation of 3-nitrotyrosine (3-NT), quantified by reverse-phase HPLC-UV analysis to increase from 0.05+/-0.03 to 0.34+/-0.11 (mol 3-NT/mol Ph-b) for 6 vs. 34 months old rats, respectively. HPLC-nanoelectrospray ionization-tandem mass spectrometry revealed the accumulation of 3-NT on Tyr113, Tyr161 and Tyr573. While nitration of Tyr113 was detected for both young and old rats, 3-NT at positions 161 and 573 was identified only for Ph-b isolated from 34 months old rats. The sequence of the rat muscle Ph-b was corrected based on our protein sequence mapping and a custom rat PHS2 sequence containing 17 differently located amino acid residues was used instead of the database sequence. The in vitro reaction of peroxynitrite with Ph-b resulted in the nitration of multiple Tyr residues at positions 51, 52, 113, 155, 185, 203, 262, 280, 404, 473, 731, and 732. Thus, the in vitro nitration conditions only mimic the nitration of a single Tyr residue observed in vivo suggesting alternative pathways controlling the accumulation of 3-NT in vivo. Our data show a correlation of age-dependent 3-NT accumulation with Ph-b inactivation.
Alternaria alternata has been reported to be the most common fungus on Canadian Western wheat. The Alternaria toxins alternariol (AOH) and alternariol monomethyl ether (AME) are mutagenic in vitro and there is also limited evidence for carcinogenic properties. They have been found in wheat from Europe, Argentina, China and Australia, but they have not been looked for in Canadian grains or grain foods. In the present study, 83 samples of grain-based food sold in Canada, including flour, bran, breakfast cereals, infant cereals and bread, were analysed for AOH and AME using extraction with methanol, clean-up on combined aminopropyl/C18 solid phase extraction (SPE) columns, and liquid chromatography (LC) with tandem mass spectrometric (MS/MS) determination. The overall average recoveries of AOH and AME from a variety of spiked cereal foods (n?=?13) were 45?±?9% and 53?±?9%, which could be attributed mainly to MS matrix effects The instrumental limits of detection (LOD) were 0.34 ng/g and 0.13 ng/g for AOH and AME, respectively, and the instrumental limits of quantitation (LOQ) were 1.1 and 0.43 ng/g. Of 83 samples analysed, 70 were positive for AOH (up to 63 ng/g, in a soft wheat bran) and 64 contained AME (up to 12 ng/g in a bran-based breakfast cereal). Of particular interest was the presence of AOH and/or AME in 27 out of 30 infant foods (up to 4.4 ng/g and 9.0 ng/g, respectively, in a sample of multigrain cereal).
Anabolic Androgenic Steroids (AAS) are considered drugs of abuse and are controlled substances in Sweden since 1999. Traditionally AAS have been used by elite athletes to enhance performance, but in recent years it has become an increasing problem outside elite sport among athletes, bodybuilders and criminals. Use of AAS is associated with psychiatric side effects such as aggression, depression and violent behavior. Supraphysiological doses and long term use can cause serious physical harm such as cardiovascular toxicity and even premature death. We investigated and evaluated the drug analytical findings in forensic cases from suspected perpetrators in cases from the police where a screening for AAS was requested to get information about the prevalence of AAS use and the occurrence of poly-drug abuse. The study was based on samples submitted from the police authorities to the Department of Forensic Toxicology in Sweden during the period 1999-2009. Urines were analyzed by methods based on GC-MS and LC-MS-MS. We also analyzed the prevalence of AAS use at the prison and probation services. A total number of 12,141 urine samples (6362 police cases and 5779 inmates) were analyzed and 33.5% of the cases from the police and 11.5% of the inmates were tested positive for AAS. The users of AAS were mainly in 99.2% men with a mean age of 26.2±6.2 years whereas the women were 29.5±6.5 years old. The most frequently used AAS was nandrolone followed by testosterone and methandienone. Other illicit and licit drugs were detected in 60% of the cases from the police, strongly indicating a frequent poly-drug abuse among users of AAS.
On October 26, 2002, Russian Special Forces deployed a chemical aerosol against Chechen terrorists to rescue hostages in the Dubrovka theatre. Its use confirmed Russian military interest in chemicals with effects on personnel and caused 125 deaths through a combination of the aerosol and inadequate medical care. This study provides evidence from liquid chromatography-tandem mass spectrometry analysis of extracts of clothing from two British survivors, and urine from a third survivor, that the aerosol comprised a mixture of two anaesthetics--carfentanil and remifentanil--whose relative proportions this study was unable to identify. Carfentanil and remifentanil were found on a shirt sample and a metabolite called norcarfentanil was found in a urine sample. This metabolite probably originated from carfentanil.
Food Research Division, Food Directorate, Health Products and Food Branch, Health Canada, 2203D, 251 Sir Frederick Banting Driveway, Tunney's Pasture, Ottawa, Ontario, Canada K1A 0K9. email@example.com
Blue-green algae and spirulina are marketed in health food stores and over the Internet as food supplements in Canada, the United States, and Europe. The reported benefits of consuming these products include improved digestion, strengthening of the immune system, and relief from the symptoms of attention deficit disorder. Some of these products have been found to contain elevated concentrations of microcystins, which are known hepatotoxins. In addition to producing microcystins, Anabaena sp. and Aphanizomenon sp. also produce the potent neurotoxin anatoxin-a. Samples of food supplements containing blue-green algae and spirulina were collected in Portugal and from urban centers across Canada in 2005. Extracts of these supplements were analyzed to determine the presence and concentrations of anatoxin-a and its two main metabolites, dihydroanatoxin-a and epoxyanatoxin-a. Initial analyses were performed using high-performance liquid chromatography (HPLC) with fluorescence detection, and confirmation required the use of LC with tandem mass spectrometry (LC-MS-MS). The HPLC with fluorescence detection indicated no anatoxin-a, but four samples were suspected to contain either dihydroanatoxin-a or epoxyanatoxin-a at 0.1 to 0.2 microg/g. LC-MS-MS results, however, indicated no trace of either transformation product in any sample analyzed. The detection limits for anatoxin-a, dihydroanatoxin-a, and epoxyanatoxin-a were similar for both fluorescence detection (0.2 to 0.3, 0.4 to 1.4, and 0.2 to 1.5 pg on the column, respectively) and mass spectrometry (0.3 to 1.5, 0.3 to 0.8, and 0.5 to 0.8 pg on the column, respectively). Because of the higher specificity of the LC-MS-MS analysis, all tested food supplement samples were considered free of anatoxin-a and its transformation products.
A fast and simple method for the analysis of 17 commonly used antibiotics in Finland in water samples was developed. The method combines online solid phase extraction using a reusable online trapping column combined with analytical separation on a C18 analytical column and detection by a triple quadrupole mass spectrometer. The method was fully validated for detection and quantification limits as well as linearity, repeatability, and matrix effects. The method gave an excellent linear response (r (2) > 0.99) and detection limits for all compounds (1-10 ng(-1)), except for tetracycline (20 ng l(-1)) and roxithromycin (50 ng l(-1)). The repeatability was evaluated at two concentrations, and the values at 5 ng l(-1) ranged from 5 to 39% and at 100 ng l(-1) ranged from 3 to 19%. To test the method on real samples at low environmental concentrations, water samples collected from a river receiving discharges from two wastewater treatment plants were analyzed as well as samples from a pristine river. Seven antibiotics as well as carbamazepine were detected in the samples. The concentration of the compounds ranged from 5 to 81 ng l(-1).
Abdominal aortic aneurysm (AAA) evolution is unpredictable, and there is no therapy except surgery for patients with an aortic size>?5 cm (large AAA). We aimed to identify new potential biomarkers that could facilitate prognosis and treatment of patients with AAA. A differential quantitative proteomic analysis of plasma proteins was performed in AAA patients at different stages of evolution [small AAA (aortic size=3-5 cm) vs large AAA] using iTRAQ labelling, high-throughput nano-LC-MS/MS and a novel multi-layered statistical model. Among the proteins identified, ApoA-I was decreased in patients with large AAA compared to those with small AAA. These results were validated by ELISA on plasma samples from small (n=90) and large AAA (n=26) patients (150± 3 vs 133± 5 mg/dl, respectively, p
Analytical methods are generally developed and optimized for specific commodities. Total Diet Studies, representing typical food products 'as consumed', pose an analytical challenge since every food product is different. In order to address this technical challenge, a selective and sensitive analytical method was developed suitable for the quantitation of ochratoxin A (OTA) in Canadian Total Diet Study composites. The method uses an acidified solvent extraction, an immunoaffinity column (IAC) for clean-up, liquid chromatography-tandem mass spectrometry (LC-MS/MS) for identification and quantification, and a uniformly stable isotope-labelled OTA (U-[(13)C(20)]-OTA) as an internal recovery standard. Results are corrected for this standard. The method is accurate (101% average recovery) and precise (5.5% relative standard deviation (RSD)) based on 17 duplicate analysis of various food products over 2 years. A total of 140 diet composites were analysed for OTA as part of the Canadian Total Diet Study. Samples were collected at retail level from two Canadian cities, Quebec City and Calgary, in 2008 and 2009, respectively. The results indicate that 73% (102/140) of the samples had detectable levels of OTA, with some of the highest levels of OTA contamination found in the Canadian bread supply.
Perfluoroalkyl substances (PFASs) are a group of highly persistent chemicals that are widespread contaminants in wildlife and humans. Exposure to PFAS affects thyroid homeostasis in experimental animals and possibly in humans. The objective of this study was to examine the association between plasma concentrations of PFASs and thyroid stimulating hormone (TSH) among pregnant women.
A total of 903 pregnant women who enrolled in the Norwegian Mother and Child Cohort Study from 2003 to 2004 were studied. Concentrations of thirteen PFASs and TSH were measured in plasma samples collected around the 18th week of gestation. Linear regression models were used to evaluate associations between PFASs and TSH.
Among the thirteen PFASs, seven were detected in more than 60% of samples and perfluorooctane sulfonate (PFOS) had the highest concentrations (median, 12.8 ng/mL; inter-quartile range [IQR], 10.1 -16.5 ng/mL). The median TSH concentration was 3.5 (IQR, 2.4 - 4.8) µIU/mL. Pregnant women with higher PFOS had higher TSH levels. After adjustment, with each 1 ng/mL increase in PFOS concentration, there was a 0.8% (95% confidence interval: 0.1%, 1.6%) rise in TSH. The odds ratio of having an abnormally high TSH, however, was not increased, and other PFASs were unrelated to TSH.
Our results suggest an association between PFOS and TSH in pregnant women that is small and may be of no clinical significance.