Pilot and definitive studies to evaluate Insertional Mutagenesis

该合同的目的是进行研究，这将有助于国家毒理学计划（NTP）在短期接触各种化学品的毒理学特性。这些研究旨在确定可能的毒性靶器官、动物性别和种属之间的敏感性差异、剂量-反应关系以及可能的毒性机制。NTP将使用慢性前研究的数据来表征和报告所研究化学品的毒性，并确定随后长期致癌性研究所选化学品的剂量水平。在转基因小鼠模型中进行的研究旨在验证模型的使用，以取代为期两年的小鼠生物测定，并获得有关肿瘤发生机制的信息。转基因模型也被用于前瞻性地评估化学品的毒理学潜力。毒理基因组学研究旨在确定是否使用基因组技术可以在较短的时间内检测出潜在的致癌物质。2006财政年度完成或正在进行以下研究：用于毒理基因组学变异性研究的RNA分离：从两个不同实验室的不同年龄的Fischer 344哨兵大鼠中分离RNA，以确定肝脏中差异基因表达（DGE）的变异性。本研究正在进行中，分离的肝脏RNA将被送往另一个合同实验室进行基因表达谱分析。雄性Fischer 344大鼠中4种大鼠肝脏致癌物和3种非致癌物的毒理基因组学评价：本研究的活体部分已由实验室完成。本研究将确定肝脏组织病理学、谷胱甘肽、临床病理学、肝脏RNA分离和后续微阵列分析、肝脏蛋白质组学和血清多分析物谱（MAP）。在CB 6 F1-Tg（HRAS 2）转基因小鼠中进行的多溴二苯醚同系物DE-47的围产期研究：实验室正在进行一项试点研究，预计2007财政年度将得出结果。壳聚糖的6个月安全性研究：本研究的活体部分正在进行中，将研究在Sprague-Dawley大鼠中以饲料给药壳聚糖对骨质减少和骨质疏松症、脂肪和钙吸收以及脂溶性维生素（A、K、E和25-羟基维生素D代谢产物）状态的影响和其他毒理学效应。通过植入式遥测技术延长比格犬的QT间期：本研究已授予实验室，以确定清醒犬无线电遥测模型用于评价使用6种药物（索他洛尔、特非尼定、苄普地尔、氯雷他定、洛伐他汀和地尔硫卓）的QT间期延长的灵敏度和特异性。.如果成功，将扩展确定性研究，以检查检测试剂盒的灵敏度和特异性。插入突变的FDA-NTP研究-初步研究：已授予实验室为期12周的初步研究，以开发和验证用于评估逆转录病毒载体介导的插入肿瘤发生风险的临床前模型。这项研究拟于2007财政年度开始。39-番泻叶在p53（+/-）转基因小鼠中的一周研究：研究已授予实验室以确定番泻叶在杂合p53（+/-）转基因小鼠模型中的毒性/肿瘤反应。研究将于2007财政年度开始。支持暴露生物学计划鼠类方案部分的熟练度评价：本项目的目标是开发一组环境因子（臭氧、香烟烟雾、内毒素和过敏原）的生物反应标志物，已知这些环境因子会干扰生物系统，导致气道变化，从而导致慢性气道疾病的发展。为了建立一个程序化的基础设施来支持这些项目，我们已经向实验室发出了一项工作任务，该任务将用于建立实验室在选定的特殊技术方面的熟练程度。 关键词毒理学评价;围产期研究;大鼠- F344/N; CB 6 F1-Tg（HRAS 2）转基因小鼠;转基因小鼠模型; RNA分离;毒理基因组学评价;微阵列;差异基因表达（DGE）;肝蛋白质组学;血清多分析物谱（MAPs）; N-乙酰基-对氨基苯酚（APAP）;亚硝基二甲胺;蒽醌;黄曲霉毒素B1;抗坏血酸; l-色氨酸;甲基丁香酚;番泻叶;多溴二苯醚同系物; PBDE-47;致癌物和非致癌物; RNA制备，壳聚糖; QT延长;插入突变;气道功能，烯丙基苯，丙烯基苯，风味成分，甲基丁香酚，黄樟素，雌草脑，异黄樟素，丁香酚，异丁香酚，肉豆蔻醚和茴香脑。

The purpose of this contract is to conduct studies, which will help the National Toxicology Program (NTP) in the toxicologic characterization associated with short-term exposures to a variety of chemicals. The studies are designed to identify possible target organs of toxicity and differences in sensitivity between sexes and species of animals and dose-response relationships, and possible mechanism of toxicity. Data from prechronic studies will be used by the NTP to characterize and report the toxicity of chemicals studied and for establishment of dose levels of chemicals selected for subsequent long-term carcinogenicity studies. The studies in genetically modified mouse models are designed to validate the use of models as a replacement of the two-year mouse bioassay and to obtain information about mechanisms involved in tumorgenesis. The transgenic models are also used prospectively to evaluate chemicals for their toxicologic potential. Toxicogenomic studies are designed to determine whether the use of genomic technology can detect potential carcinogens in a shorter time frame. The following studies have been completed or are ongoing during FY 2006: RNA isolation for Toxicogenomic Variability Study: RNA is being isolated from sentinel Fischer 344 rats of varying ages from two different laboratories to determine the variability of Differential Gene Expression (DGE) in liver. This study is ongoing and the isolated hepatic RNA will be sent to another contract lab for gene expression profiling. Toxicogenomic evaluation of four rat liver carcinogens and three non-carcinogens in male Fischer 344 rats: The in-life portion of this study has been completed by the lab. Liver histopathology, glutathione, clinical pathology, hepatic RNA isolation and subsequent microarray profiling, liver proteomics and serum multiple analyte profiles (MAPs) will be determined in this study. Perinatal study of polybrominated diphenyl ether congener DE-47 in CB6F1-Tg(HRAS2) transgenic mice: A pilot study is being performed at the lab and the results are expected in FY 2007. Six Month Safety Study of Chitosan: The in-life portion of this study is ongoing and will investigate the effect of chitosan administered in dosed feed on bone osteopenia and osteoporosis, on fat and calcium absorption, and on the status of fat soluble vitamins (A, K, E, and 25-hydroxy vitamin D metabolites) and other toxicological effects in Sprague-Dawley rats. QT Prolongation in Beagle Dog via Implantable Telemetry: This study has been awarded to the lab to determine the sensitivity and specificity of the conscious canine radio telemetry model for the evaluation of QT interval prolongation using six drugs (Sotalol, Terfenedine, Bepridil, Loratadine, Lovastatin, and Diltiazem). . If successful, definitive studies will be extended to examine the sensitivity and specificity of the assay. FDA-NTP Studies of Insertional Mutagenesis - Pilot Study: 12-week pilot study has been awarded to the lab to develop and validate preclinical model for assessing risk of retroviral vector-mediated insertional tumorgenesis. The study is proposed to start in FY 2007. 39-week study of Senna in p53 (+/-) transgenic mice: Study has been awarded to the lab to determine the toxic/neoplastic responses of Senna in heterozygous p53 (+/-) transgenic mouse model. Studies will start in FY-2007. Proficiency Evaluation in Support of the Murine Protocol Section of the Exposure Biology Program: The goal of this project is to develop a panel of biologic response markers for environmental agents (ozone, cigarette smoke, endotoxin, and allergen) that are known to perturb biologic systems resulting in changes in the airway that lead to the development of chronic airway disease. In order to establish a programmatic infrastructure to support these projects we have issued a work assignment to the lab that will be used to establish laboratory proficiency in selected special techniques. Keywords Toxicologic evaluation; Perinatal study; Rats- F344/N; CB6F1-Tg(HRAS2)transgenic mice; Genetically Modified Mouse Models; RNA isolation; Toxicogenomic evaluation; Microarray; Differential Gene Expression (DGE);liver proteomics; serum multiple analyte profiles (MAPs); N-acetyl-p-Aminophenol(APAP); Nitrosodimethylamine; Anthraquinone; Aflatoxin B1; Ascorbic acid; l-tryptophan; Methlyeugenol; Senna; PolyBrominated diphenyl ether congeners; PBDE-47; Carcinogen and Non-carcinogen; RNA Preparation, Chitosan; QT Prolongation; Insertional Mutagenesis; Airway Proficiency, Allylbenzene, Propenylbenzene, Flavor constituents, Methyleugenol, Safrole, Estragole, Isosafrole, Eugenol, Isoeugenol, Myristicin, and Anethole.