Behl M.,Kelly Government Solutions Inc. |
Behl M.,National Health Research Institute |
Elmore S.A.,National Health Research Institute |
Malarkey D.E.,National Health Research Institute |
And 3 more authors.
Toxicology | Year: 2013
Styrene acrylonitrile (SAN) trimer is a by-product in the production of acrylonitrile styrene plastics. Following a report of a childhood cancer cluster in the Toms River section of Dover Township, New Jersey, SAN Trimer was identified as one of the groundwater contaminants at Reich Farm Superfund site in the township. The contaminants from the Reich Farm site's ground water plume impacted two wells at the Parkway well field. The National Toxicology Program (NTP) studied the toxicity and carcinogenicity of SAN Trimer in rats exposed during their perinatal developmental period and adulthood. The chronic toxicity and carcinogenicity studies in F344/N rats were preceded by 7- and 18-week perinatal toxicity studies to determine the exposure concentrations for the 2-year studies. Subsequently, Fisher 344 pregnant dams were exposed to SAN Trimer containing diet at 400, 800, or 1600. ppm concentrations during gestation, nursing and weaning periods of offspring followed by two year of adult exposures to both male and female pups. There was no statistically significant evidence of carcinogenic activity following SAN-Trimer exposure; however, rare neoplasms in the brain and spinal cord were observed in males and to lesser extent in female rats. These incidences were considered within the range of historical background in the animal model used in the current studies. Therefore, the presence of a few rarely occurring CNS tumors in the treated groups were not judged to be associated with the SAN Trimer exposure. The major finding was a dose-related peripheral neuropathy associated with the sciatic nerves in females and spinal nerve roots in males and females thereby suggesting that SAN Trimer is potentially a nervous system toxicant. © 2013.
Behl M.,Kelly Government Solutions Inc. |
Behl M.,U.S. National Institutes of Health |
Rao D.,Integrated Laboratory Systems, Inc. |
Aagaard K.,Baylor College of Medicine |
And 9 more authors.
Environmental Health Perspectives | Year: 2013
Background: An emerging literature suggests that environmental chemicals may play a role in the development of childhood obesity and metabolic disorders, especially when exposure occurs early in life. Objective: Here we assess the association between these health outcomes and exposure to maternal smoking during pregnancy as part of a broader effort to develop a research agenda to better understand the role of environmental chemicals as potential risk factors for obesity and metabolic disorders. Methods: PubMed was searched up to 8 March 2012 for epidemiological and experimental animal studies related to maternal smoking or nicotine exposure during pregnancy and childhood obesity or metabolic disorders at any age. A total of 101 studies-83 in humans and 18 in animals-were identified as the primary literature. Discussion: Current epidemiological data support a positive association between maternal smoking and increased risk of obesity or overweight in ofspring. The data strongly suggest a causal relation, although the possibility that the association is attributable to unmeasured residual confounding cannot be completely ruled out. This conclusion is supported by findings from laboratory animals exposed to nicotine during development. Te existing literature on human exposures does not support an association between maternal smoking during pregnancy and type 1 diabetes in ofspring. Too few human studies have assessed outcomes related to type 2 diabetes or metabolic syndrome to reach conclusions based on patterns of findings. There may be a number of mechanistic pathways important for the development of aberrant metabolic outcomes following perinatal exposure to cigarette smoke, which remain largely unexplored. Conclusions: From a toxicological perspective, the linkages between maternal smoking during pregnancy and childhood overweight/obesity provide proof-of-concept of how early-life exposure to an environmental toxicant can be a risk factor for childhood obesity.
Camp K.M.,Kelly Government Solutions Inc. |
Trujillo E.,U.S. National Institutes of Health
Journal of the Academy of Nutrition and Dietetics | Year: 2014
It is the position of the Academy of Nutrition and Dietetics that nutritional genomics provides insight into how diet and genotype interactions affect phenotype. The practical application of nutritional genomics for complex chronic disease is an emerging science and the use of nutrigenetic testing to provide dietary advice is not ready for routine dietetics practice. Registered dietitian nutritionists need basic competency in genetics as a foundation for understanding nutritional genomics; proficiency requires advanced knowledge and skills. Unlike single-gene defects in which a mutation in a single gene results in a specific disorder, most chronic diseases, such as cardiovascular disease, diabetes, and cancer are multigenetic and multifactorial and therefore genetic mutations are only partially predictive of disease risk. Family history, biochemical parameters, and the presence of risk factors in individuals are relevant tools for personalizing dietary interventions. Direct-to-consumer genetic testing is not closely regulated in the United States and may not be accompanied by access to health care practitioners. Applying nutritional genomics in clinical practice through the use of genetic testing requires that registered dietitian nutritionists understand, interpret, and communicate complex test results in which the actual risk of developing a disease may not be known. The practical application of nutritional genomics in dietetics practice will require an evidence-based approach to validate that personalized recommendations result in health benefits to individuals and do not cause harm. © 2014 Academy of Nutrition and Dietetics.
Strong D.R.,University of California at San Diego |
Hartman S.J.,University of California at San Diego |
Nodora J.,University of California at San Diego |
Messer K.,University of California at San Diego |
And 6 more authors.
Nicotine and Tobacco Research | Year: 2015
Objectives: The susceptibility to smoking index can be improved as it only identifies one third of future adult smokers. Adding curiosity to this index may increase the identification of future smokers and improve the identification of effective prevention messages. Methods: Analyses used data from the California Longitudinal Study of Smoking Transitions in Youth, for whom tobacco use behaviors, attitudes, and beliefs were assessed at 3 time points from age 12 through early adulthood. Logistic regressions were used to evaluate whether baseline curiosity about smoking was predictive of smoking during the 6-year follow-up period and whether curiosity about smoking provided evidence of incremental validity over existing measures of susceptibility to smoking. Results: Compared to those who were classified as definitely not curious about smoking, teens who were classified as probably not curious (ORadj = 1.90, 95% CI = 1.28-2.81) and those classified as definitely curious (ORadj = 2.38, 95% CI= 1.49-3.79) had an increase in the odds of becoming a young adult smoker. Adding curiosity to the original susceptibility to smoking index increased the sensitivity of the enhanced susceptibility index to 78.9% compared to 62.2% identified by the original susceptibility index. However, a loss of specificity meant there was no improvement in the positive predictive value. Conclusions: The enhanced susceptibility index significantly improves identification of teens at risk for becoming young adult smokers. Thus, this enhanced index is preferred for identifying and testing potentially effective prevention messages. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved.
Davis M.,U.S. National Cancer Institute |
Li J.,Kelly Government Solutions Inc. |
Li J.,National Health Research Institute |
Knight E.,U.S. National Cancer Institute |
And 3 more authors.
Frontiers in Genetics | Year: 2015
Combinations of anticancer agents may have synergistic anti-tumor effects, but enhanced hematological toxicity often limit their clinical use. We examined whether "microarray profiles" could be used to compare early molecular responses following a single dose of agents administered individually with that of the agents administered in a combination. We compared the mRNA responses within bone marrow of Sprague-Dawley rats after a single 30 min treatment with topotecan at 4.7 mg/kg or oxaliplatin at 15 mg/kg alone to that of sequentially administered combination therapy or vehicle control for 1, 6, and 24 h. We also examined the histopathology of the bone marrow following all treatments. Drug-related histopathological lesions were limited to bone marrow hypocellularity for animals dosed with either agent alone or in combination. Lesions had an earlier onset and higher incidence for animals given topotecan alone or in combination with oxaliplatin. Severity increased from mild to moderate when topotecan was administered prior to oxaliplatin compared with administering oxaliplatin first. Notably, six patterns of co-expressed genes were detected at the 1 h time point that indicate regulatory expression of genes that are dependent on the order of the administration. These results suggest alterations in histone biology, chromatin remodeling, DNA repair, bone regeneration, and respiratory and oxidative phosphorylation are among the prominent pathways modulated in bone marrow from animals treated with an oxaliplatin/topotecan combination. These data also demonstrate the potential for early mRNA patterns derived from target organs of toxicity to inform toxicological risk and molecular mechanisms for agents given in combination. © 2015 Davis, Li, Knight, Eldridge, Daniels and Bushel.