JULY: NCTR RESEARCH HIGHLIGHTS
Measurement of Melamine and Cyanuric Acid in Complex Food Matricies
NCTR organic chemists have synthesized and supplied to a number of laboratories non-radioactive melamine and cyanuric acid standards for certification of analytical methods that will be used for evaluating the levels of these contaminants in foods. The laboratories include the Animal Drug Research Center, Denver District Office; the Kansas City District Office; USDA, FSIS, OPHS; CFSAN; CVM; ORA Forensic Chemistry Center; and the Arkansas Regional Laboratory.
The challenge of quantitatively determining levels of contamination of melamine and cyanuric acid in complex food matrices or animal tissues is extremely difficult without isotopically labeled internal standards.
These custom synthesized chemicals, incorporating heavy nitrogen (15N) or carbon (13C), are not commercially available and can be conveniently used to assay very low levels using mass spectrometry techniques. The utilization of non-radioactive isotopes in the compounds also has the advantage of reducing environmental problems that are encountered with the use of radioactively labeled standards.
For further information, contact Dr. Frederick A. Beland, Director, Division of Biochemical Toxicology, NCTR.
Critical Path – Impact of Genomics Technologies on Regulatory Policies
Escalating amounts of information and a panoply of methodologies emanating from genomics research are clearly impacting the disciplines of toxicology and public health. As greater insight from these technologies is obtained, there is increasing focus and pressure on governmental regulatory agencies to evaluate the utility and validity of information generated using “omics" technologies. Several government agencies, including but not limited to the Food and Drug Administration, Department of Agriculture, and Environmental Protection Agency, have been addressing many of the issues raised by “omics” technologies.
A recent symposium entitled “Impact of Genomic Technologies on Regulatory Policies", planned by FDA and USDA scientists, was held at the 37th Annual Meeting of the Environmental Mutagen Society. The symposium provided an opportunity to review the strategic plans of various governmental agencies regarding the use of “omics” data in regulatory toxicology.
In addition, a special workshop entitled “Progress in Omics Technologies" provided a forum in which to highlight specific technological advances. Peer-reviewed manuscripts describing FDA, EPA, and USDA current thinking on these issues, along with technical strengths and limitations of “omics” technologies, were recently published under the editorship of Dr. James Fuscoe (FDA) and Dr. Kerry Dearfield (USDA). The set of manuscripts (Environmental and Molecular Mutagenesis 48:5, 2007) collectively outlines the impact of “omics” technologies on regulatory programs and policies. These policies will play a major role in the implementation of genomics technologies as they relate to important public health issues and movement toward personalized medicine.
For further information, contact Dr. James Fuscoe, Division of Systems Toxicology, NCTR, 870-543-7126.
AUGUST: NCTR RESEARCH HIGHLIGHTS
Continuous Quality Improvement - NCTR Division of Microbiology’s Research and Surveillance Programs reviewed
On July 24-25, 2007, the NCTR Division of Microbiology’s Research and Surveillance Programs were reviewed by a subcommittee of the NCTR Science Advisory Board that includes FDA liaison members. The review subcommittee included scientists from government, industry, and academia and was chaired by Dr. Anthony L. Pometto, Professor, Department of Food Science & Human Nutrition, Iowa State University. Representatives from CFSAN, CVM, CBER, and ORA participated in the review. Dr. Carl E. Cerniglia, Director of the Division of Microbiology, presented an overview of the research program, and the division research scientists described their current research interests.
Preliminary feedback from the reviewers noted that this program is to be complimented for its expertise and diverse research collaborations supporting FDA initiatives, such as antimicrobial resistance, food safety and biosecurity, gastrointestinal and host interactions, environmental biotechnology, and overall surveillance in support of the broader NCTR research community.
NCTR Scientists Participate in CFSAN Food Safety Grand Rounds
The first CFSAN Office of Food Additive Safety Grand Rounds of 2007 was held on July 31 and August 1, and addressed the topic Genetic Toxicology: Supporting Regulatory Decisions.
The agenda included a discussion of the latest developments in the optimal use of the current regulatory assays, new approaches to using in vivo mutation data to inform risk assessment, and the development of new genetic toxicology methods to improve regulatory decisions. Speakers included five NCTR scientists, one former NCTR scientist, and a guest speaker from Europe.
The discipline of genetic toxicology is concerned with assessing the ability of chemicals to alter genetic material. Because genetic damage is important in tumor development, data on the potential toxicity of a substance is used as a part of the evaluation of food substances, both for approval and for other regulatory decisions.In addition to the scientific presentations, the Grand Rounds provided an opportunity for CFSAN and NCTR scientists to share information and develop new ideas for continued collaboration and exchange of technical expertise.
NCTR Hosts FDA Assistant Commissioner for Food Protection
On August 7-8, 2007, Dr. David Acheson visited the NCTR. His seminar presentation, titled Food Protection, provided the NCTR/Jefferson Laboratories staff with a better understanding of the linkage of food defense and food/feed safety that comprise the Food Protection initiative in the Agency. Each NCTR division provided a brief overview of their research focus and capabilities followed by a walking tour of the NCTR/Jefferson Laboratories campus. Dr. Acheson’s visit provided him with a better understanding of how NCTR expertise and capabilities can assist him in addressing food protection issues for the Agency.
NCTR welcomes new Pine Bluff Arsenal Commander
NCTR, located in Jefferson, Arkansas, sits adjacent to the Army's Pine Bluff Arsenal (PBA). On August 15, 2007, Dr. William Slikker hosted a visit and tour of NCTR for the recently appointed PBA Commander, Colonel William Barnett; his Civilian Executive Assistant, Mr. Larry Wright; and the recently appointed commander of the Pine Bluff Chemical Activity, Lt. Colonel Clifton Johnston; and his Civilian Executive Assistant, Mr. Steve Lowry. Dr. Slikker presented an overview of NCTR capabilities followed by a walking tour of the Center. Discussions during the visit resulted in an agreement to initiate a series of seminars between the facilities to identify potential areas of collaboration in addition to continuing the ongoing IAG with the PBA for provision of essential support services to the NCTR/Jefferson Laboratories community.
SEPTEMBER: NCTR RESEARCH HIGHLIGHTS
On August 21, Price Feland, Arkansas Senator Mark Pryor’s Legislative Assistant, visited NCTR. Mr. Feland met with NCTR Director, Dr. William Slikker, Jr., who presented an overview of NCTR's programs followed by a tour of the Center. Included in his tour were the Divisions of Neurotoxicology (Dr. Merle Paule) and Microbiology (Dr. John Sutherland) and two Centers of Excellence, Metabolomics in the Division of Systems Toxicology (Drs. Rick Beger and Laura Schnackenberg) and Phototoxicology in the Division of Biochemical Toxicology (Dr. Paul Howard). Mr. Feland was especially interested in the work assessing toxicity related to nano particles.
New Pine Bluff Arsenal Commander
NCTR, located in Jefferson, Arkansas, sits adjacent to the Army's Pine Bluff Arsenal (PBA). On August 15, Dr. William Slikker hosted a visit and tour of NCTR for the recently appointed PBA Commander, Colonel William Barnett, and his Civilian Executive Assistant, Mr. Larry Wright; and the recently appointed commander of the Pine Bluff Chemical Activity, Lt. Colonel Clifton Johnston, and his Civilian Executive Assistant, Mr. Steve Lowry. Dr. Slikker presented an overview of NCTR capabilities followed by a walking tour of the Center. Discussions during the visit resulted in an agreement to initiate a series of seminars between the facilities to identify potential areas of collaboration in addition to continuing the ongoing Interagency agreement with the PBA for provision of essential support services to the NCTR/Jefferson Laboratories community.
Critical Path – NCTR Research on Genomics Helps the Development of New Guidance Document for Industry on Pharmacogenomic Data Submissions
On August 28, 2007, the FDA issued a new draft guidance for industry, “Pharmacogenomic Data Submissions - Companion Guidance”. This new guidance, to be used as a companion to the guidance “Pharmacogenomic Data Submissions” (March 2005), reflects experiences the Agency gained over the past three years. NCTR scientists have been instrumental in the management, analysis, and interpretation of Voluntary Genomic Data Submissions (VGDS) by providing a much-needed bioinformatics infrastructure (ArrayTrack™) and through close collaborations with scientists and reviewers from CDER, CBER, and CDRH. In addition, NCTR has been leading the MicroArray Quality Control (MAQC) project, a community-wide effort (with participation of all six FDA Centers) aimed at addressing performance, standards, quality, and data analysis issues on the application of microarray genomic data in clinical and preclinical settings. Experiences gained through the VGDS and MAQC efforts provided the regulatory and scientific foundations for the newly released pharmacogenomics guidance.
For further information, contact Dr. Weida Tong, Division of Systems Toxicology, NCTR, 870-543-7142.
NCTR Honor Awards Ceremony
The National Center for Toxicological Research (NCTR) held its annual honor awards ceremony on August 29, 2007, at the Harbor Oaks Championship Golf Course & Restaurant located in Pine Bluff, Arkansas. The honor awards ceremony recognized employees for outstanding accomplishments in support of the DHHS, FDA, and the NCTR. Awards presented included the: DHHS/PHS Outstanding Unit Citation, DHHS/PHS Crisis Response Service Award, FDA Commissioner’s Special Citation, Award of Merit, Group Recognition Award, Outstanding Service Award; Equal Opportunity Achievement Award, Quality-of-Work-Life Award, Leveraging/Collaboration Award, Diversity-in-Action Award, and Scientific Achievement Award. NCTR’s honor awards presented included the: NCTR Director’s Award, Outstanding Service Award, and Quality-of-Work-Life Awards. NCTR Director, Dr. William Slikker, Jr., presented the awards with assistance from the employee’s supervisors and/or government project officers to the recipients in front of their peers. Mrs. Vicky Ross-Barsh, Associate Director for Management Services, emceed the ceremony. In recognition of the occasion, the honorees participated in a luncheon preceding the ceremony.
Dietary Supplements - Usnic Acid
NCTR and CFSAN scientists have demonstrated that usnic acid preparations derived from Usnea lichens are significantly more toxic when fed to mice and rats than pure preparations of the acid.
It is known that high doses of usnic acid consumed as a fat burning agent has been associated with severe hepatotoxicity in humans, and currently dietary supplements marketed with low concentrations of acid from the Usnea lichen preparations are consumed for antimicrobial properties. The rodent studies showed that high doses of the acid (>100mg/kg/day) caused severe weight loss, hepatocellular damage, and thymic atrophy. Lower doses did not produce weight loss effects, but they did produce minimal hepatotoxicity. The low doses resulted in the induction of liver cytochrome P450s, enzymes very prominent in drug metabolism, signaling a high concern for effects in individuals on prescription drugs. Additional studies investigating the subchronic toxicity of usnic acid are being pursued. Supporting funding for this work is obtained from the National Toxicology Program.
For further information, contact Dr. William Slikker, Jr. or Dr. William Allaben at NCTR.
NCTR Scientist Provides Training to CBER and CDER PharmTox Reviewers
Dr. Martha Moore, Chair of the Mouse Lymphoma Assay Workgroup of the International Workshop on Genotoxicity Test Procedures (IWGT), conducted a training session for CBER and CDER PharmTox reviewers on September 25th. The training provided reviewers with the latest internationally harmonized consensus standards for the proper interpretation of mouse lymphoma gene mutation assay (MLA) data that are submitted as a part of preclinical safety evaluations. Reviewers submitted troublesome data sets, and the interpretation of positive and negative responses was discussed. The information in the training class was the result of a multiple-year effort by IWGT to standardize the MLA. The MLA panel is comprised of experts from Japan, Europe, and the United States.
For further information, contact Dr. Martha Moore at NCTR.