About FDA
Center for Veterinary Medicine (CVM)
2010 Preceptors
- Jamie L Boehmer, Ph.D.
- Pak-Sin Chu, Ph.D.
- Maureen K. Davidson, Ph.D.
- Hiranthi Jayasuriya, Ph.D.
- Haile Yancy, Ph.D.
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Office of Research Division of Animal Research Center for Veterinary Medicine (CVM) Laurel, MD Background B.S. – University of Maryland M.S. – Virginia Polytechnic Institute and State University Ph.D. – University of Maryland FDA Experience – 6 Years
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Research Interests Dr. Boehmer’s primary research focus is the application of mass spectrometry-based proteomic approaches to the analysis and quantification of differential protein expression in complex biological matrices for the discovery of candidate biomarkers of disease in food animals. Dr. Boehmer’s research supports efforts in the Office of New Animal Drug Evaluation (ONADE) to identify biomarkers that could be used to evaluate the efficacy of new veterinary drugs, especially drugs intended for use in food animals that have anti-inflammatory claims. Specific studies have involved the identification of biomarkers of coliform mastitis in bovine milk, as well as the evaluation of antimicrobial peptides present in bovine bronchial fluid during pneumonia. Analyses are currently being conducted to evaluate the response of candidate biomarkers to drug administration, which could facilitate the use of biomarkers to assess drug efficacy, and could lead to the approval of new veterinary drugs for use in food animals. Proposed Research Project for FDA Commissioner’s Fellow The Fellow would have the opportunity to work on all aspects of the development of high-throughput proteomic methods for screening biomarker response to drug administration in large and small ruminant models, including the collection and preparation of complex biological samples, as well as protein identification and quantification using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS.) Additionally, the Fellow would investigate correlations between in vivo and in vitro proteomic screens to assess the feasibility of utilizing isolated cell lines in challenge studies as a means of modeling in vivo host response. Select Recent Publications Boehmer, J.L., Ward, J.L., Peters, R.R., Shefcheck, K.J., McFarland, M.A., and Bannerman, D.D. 2009. Proteomic Analysis of the Temporal Expression of Bovine Milk Proteins during Coliform Mastitis and Relative Quantification using a Label-Free Approach. J Dairy Sci. (accepted). Boehmer, J.L., Bannerman, D.D., Shefcheck, K.J., and Ward, J.L. 2008. Proteomic Analysis of Differentially Expressed Proteins in Bovine Milk during Experimentally Induced Escherichia coli Mastitis. J Dairy Sci. 91(11):4206-18. Reimschuessel., Gieseker, C.M., Miller, R.A., Ward, J.L., Boehmer, J.L., Rummel, N., Heller, D., Nochetto, C., Hemakanthi de Alwis, G.K., Bataller, N., Andersen, W.C., Turnipseed, S.B., Karbiwnyk, C.M., Satzger, R.D., Crowe, J.B., Wilber, N.R., Reinhard, M.K., Roberts, J.F., and Witkowski, M.R. 2008. Histopathology of renal crystals in fish and pigs exposed to melamine and cyanuric acid. Am. J Vet Res. 69 (6): 1217-1228. Martin DN, Balgley B, Dutta S, Chen J, Rudnick P, Boehmer J, Kantartzis S, DeVoe DL, Lee C, and Baehrecke EH. 2007. Proteomic analysis of steroid-triggered autophagic programmed cell death during Drosophila development. Cell Death Differ. 14(5):916-23.
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Division of Residue Chemistry Center for Veterinary Medicine (CVM) Laurel, MD Background B.S., M.S., Ph.D. – University of California, Davis FDA Experience – 17 Years
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Research Interests Dr. Chu’s research focuses on analytical method development for drug residues in biological matrices and on their metabolism and disposition in animals. His current research efforts are aimed at developing analytical methodologies for hormones and for their metabolites. Conventional methods of determining hormone residues typically involve an initial hydrolysis of the phase II conjugates followed by derivatization and detection on gas chromatography–mass spectrometry. Information concerning the identity of the conjugates (glucuronides or sulfates), however, is lost after hydrolysis. For this reason, Dr. Chu is investigating new approaches of detecting and quantifying the intact phase II conjugates using liquid chromatography–tandem mass spectrometry. Proposed Research Project for FDA Commissioner’s Fellow The Fellow will participate in the method development, characterization, and identification of in vivo metabolites of hormones in fish using a variety of separation techniques and state-of-the-art instruments, such as liquid chromatography–tandem mass spectrometry. Through hands-on experience, the Fellow will attain a thorough understanding of separation science and its applications to methods development and metabolite identification. Emerging from this work will be the availability of sensitive multi-residue methods for determination of hormones in fish as well as innovative methodologies of detecting hormones and their metabolites. The Fellow is encouraged to publish and present the research findings in scientific meetings. In addition, the Fellow will gain valuable experience in a regulatory setting and conduct research in accordance with the Good Laboratory Practice and with the appropriate regulatory guidelines. Project Requirements Ph.D. in chemistry with training in separation science and analytical chemistry. Select Recent Publications Pak-Sin Chu, Mayda I. Lopez, Ann Abraham, Kathleen R. El Said, Steven M. Plakas “Residue Depletion of Nitrofuran Drugs and Their Tissue-Bound Metabolites in the Channel Catfish (Ictalurus Punctatus) after Oral Dosing” J. Agric. Food Chem. J. Agric. Food Chem. 56, 8030–8034 (2008). Mayda I. Lopez, Jeffery S. Pettis, Barton I. Smith, and Pak-Sin Chu “Multi-class Determination and confirmation of Antibiotic Residues in Honey Using LC-MS/MS.” J. Agric. Food Chem. 56, 1553-1559 (2008). Badar Shaikh, Nathan Rummel, Charles Gieseker, Pak-Sin Chu and Renate Reimschuessel “Residue Depletion of Tritium-labeled Ivermectin in Rainbow Trout Following Oral Administration.” Aquaculture 272, 192-198 (2007). Pak-Sin Chu and Mayda I. Lopez “Determination of Nitrofuran Residues in Milk of Dairy Cows Using Liquid Chromatography-Tandem Mass Spectrometry.” J. Agric. Food Chem. 55, 2129-2135 (2007). Mayda I. Lopez, Mark F. Feldlaufer, Anthony D. Williams, and Pak-Sin Chu “Determination and Confirmation of Nitrofuran Residues in Honey Using LC-MS/MS.” J. Agric. Food Chem. 55, 1103-1108 (2007). Pak-Sin Chu, Mayda I. Lopez, Stan Serfling, Charlie Gieseker, and Renate Reimschuessel “Determination of 17α-Methyltestosterone in Muscle Tissues of Tilapia, Rainbow Trout, and Salmon Using Liquid Chromatography-Tandem Mass Spectrometry.” J. Agric. Food Chem. 54, 3193-3198 (2006). Pak-Sin Chu and Mayda I. Lopez “Liquid Chromatography-Tandem Mass Spectrometry for the Determination of Protein-Bound Residues in Shrimp Dosed with Nitrofurans.” J. Agric. Food Chem. 53, 8934-8939 (2005). Pak-Sin Chu, Ro-Chen Wang, and Hiufung V. Chu “Liquid Chromatographic Determination of Fluoroquinolones in Egg Albumen and Egg Yolk of Laying Hens Using Fluorometric Detection.” J. Agric. Food Chem. 50, 4452-4455 (2002). Pak-Sin Chu, Dan J. Donoghue, and Badar Shaikh “Determination of Total 14C Residues of Sarafloxacin in Eggs of Laying Hens.” J. Agric. Food Chem. 48, 6409-6411 (2000). Badar Shaikh and Pak-Sin Chu “Distribution of Total 14C Residue in Egg Yolk, White and Tissues Following Oral 14C-Sulfamethazine Administration to Hens.” J. Agric. Food Chem. 48, 6409-6411 (2000). |
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Office of Research Division of Animal & Food Microbiology Center for Veterinary Medicine (CVM) Laurel, MD Background M.S., Ph.D., MT (ASCP) FDA Experience – 3 Years |
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Research Interests Infectious diseases; Microbiology;Immunology;Host-parasite relationships in infectious diseases; virulence mechanisms of microorganisms; host defense mechanisms; development of diagnostic tests for infectious diseases of animals Proposed Research Project for FDA Commissioner’s Fellow Antimicrobial susceptibility and genotyping of veterinary bacterial pathogens. The use of antibiotics for the treatment and control of pathogenic bacteria is needed to ensure both healthy pets and to rear healthy food animals destined for human consumption. While much effort has been focused on zoonotic pathogens and the consequences of resistance to human health, relatively little is known about the mechanisms of resistance compromising the treatment of animal pathogens. In this study, we will examine various veterinary pathogens for susceptibility to antibiotics, the genes underlying resistance, and the genetic relatedness of strains from different sources. The Fellow will become familiar with laboratory techniques for measuring antibiotic resistance, genetic methods for characterizing resistance traits, and molecular typing tools used to assess the evolutionary relationships among strains. Project Requirements Minimum degree: Ph.D in any scientific field Minimal experience: Experience with laboratory methods. College level microbiology or immunology coursework and laboratory experience preferred Select Recent Publications Schoeb TR, Dybvig K, Davidson MK, Davis JK. Detection of urogenital mycoplasma and ureaplasma infections in primates by polymerase chain reaction (PCR). Lab Anim Sci.47: 468-471.1997 Schoeb TR, Dybvig K, Davidson MK, Davis JK. Detection of Mycoplasma pulmonis in cilia-associated respiratory bacillus isolates and in respiratory tracts of rats by nested PCR. . J Clin Microbiol 35: 1667-1670.1997. Reyes, L., Davidson, MK., Thomas, L. Davis, JK. Effects of Mycoplasma fermentans strain incognitus on differentiation of THP-1 cells. Infect. Immun. 1999 67: 3188-3192. Dohm, ED., Richards, DS, Robertson, JA., Theele, DP., Schoeb, TR., Davis, JK., Thomas, LC., Davidson, MK. Vertical Transmission of Ureaplasma urealyticum in Pregnant Pigtail Macaques (Macaca nemestrina). 1999 Infect Dis Rev 1(3):208-213. Schleig, PM, Buergelt, CD, Davis, JK, Williams,E, Monif, GRG, and Davidson, MK. Attachment of Mycobacterium avium subspecies paratuberculosis to bovine intestinal organ Cultures: Method Development and Strain Differences. Vet Microbiol. 108: 271-279. 2005 Haulena M. , Gulland FMD, Lawrence JA, Fauquier DA, Jang S, Aldridge B, Spraker T, Thomas LC, Brown D, Wendland L , and Davidson MK. Lesions associated with a novel Mycoplasma sp. in stranded California sea lions (Zalophus californianus) undergoing rehabilitation. J. Wildlife Diseases 42: 40-45. 2006 Neverov, AA, George, J, Kong, H, Liu, SX, Anderson, C, Davidson MK, Chizhikov, VE. Genetic Analysis of Housekeeping Genes of Members of the Genus Acholeplasma: Phylogeny and Complementary Molecular Markers to the 16S rRNA Gene. Molecular Phylogenetics and Evolution. 44 (2): 699-710. 2007 Schoeb TR, McConnell EE, Juliana MM, Davis JK, Davidson MK, Lindsey JR. Mycoplasma pulmonis and lymphoma in bioassays in rats. Vet Pathol. 2009 Sep;46(5):952-9.
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Division of Residue Chemistry Center for Veterinary Medicine (CVM) Laurel, MD Background Ph.D. - Natural Products Chemistry, University of Mississippi 2008 FDA Commissioners’ Fellow
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Research Interests Structure elucidation of unknown metabolites, and metabolic profiling of steroids in animal tissue using the high resolution capabilities of the Q-TOF mass spectrometer. Validation of sensitive methods to analyze for steroid residues at lower ppb level in animal tissues by LC/MS/MS. Synthesis of analytical standards of steroidal analogs that is not commercially available. Proposed Research Project for FDA Commissioner’s Fellow The identification and quantification of metabolites requires specific analytical methods and therefore sample preparation is an essential part of the analytical procedure. Interfering matrix compounds, such as proteins, salts and endogenous and background compounds, will be removed in sample pretreatment to improve the selectivity, sensitivity and reliability of analysis. The Fellow will have the opportunity to explore and develop simple high throughput sample preparation methods for LC/MS/MS analysis of steroid residues from complex matrices such as bile, liver and kidney extracts of animals. The project will also require compilation of steroidal libraries to be used in conjunction with the mass profiler professional software of the Q-TOF instrument for metabolic profiling. Project Requirements Strong Chemistry background and analytical capabilities. Selected Recent Publications Sheo B. Singh, John G. Ondeyka, Kithsiri B. Herath, Chaowei Zhang, Hiranthi Jayasuriya, Deborah L. Zink, Gopalakrishnan Parthasarathy, Joseph W. Becker, Jun Wang, Stephen M. Soisson, Isolation, enzyme-bound structure and antibacterial activity of platencin A1 from Streptomyces platensis, Bioorganic & Medicinal Chemistry Letters, 2009 (19) 4756–4759. Sheo B. Singh *, Hiranthi Jayasuriya, Kithsiri B. Herath, Chaowei Zhang, John G. Ondeyka, Deborah L. Zink, Sookhee Ha, Gopalakrishnan Parthasarathy, Joseph W. Becker, Jun Wang, Stephen M. Soisson, Isolation, enzyme-bound structure, and activity of platensimycin A1 from Streptomyces platensis, Tetrahedron Letters, 2009 (50) 5182–5185. Jayasuriya, H., Zink, D., Basilio, A.,Vicente, F., Collado, J., Bills, G., Goldman, M.L. , Motyl, M. , Huber, J. , Dezeny, G., Byrne, K. , Singh. S.B., Discovery and antibacterial activity of glabramycin A-C from Neosartorya glabra by an antisense strategy, J. Antibiotics, 2009, 62(5), 265-269. Zhang, C.W. , Herath, K. , Jayasuriya, H. , Ondeyka, J.G. , Zink, D.L., Occi, J., Birdsall, G. , Venugopal, J. , Ushio, M. , Burgess, B. , Masurekar, P., Barrett, J.F., Singh S.B., Thiazomycins, Thiazolyl Peptide Antibiotics from Amycolatopsis fastidiosa, Journal of Natural Products, 2009, 72(5) 841-847. Herath, K.B. , Zhang, C.W., Jayasuriya, H. , Ondeyka, J.G. , Zink, D.L., Burgess, B. , Wang, J. , Singh,S.B., Structure and Semisynthesis of Platensimide A, Produced by Streptomyces platensis, Organic Letters, 2009, 11( 9), 2043. Herath, K. , Harris, G. , Jayasuriya, H. , Zink, D. , Smith S , Vicente, F. , Bills, G. , Collado, J., Gonzalez, A. , Jiang, B. , Kahn, J.N. , Galuska, S. , Giacobbe, R. , Abruzzo, G. , Hickey, E., Liberator, P., Xu, D.M. , Roemer, T., Singh, S.B., Isolation, structure and biological activity of phomafungin, a cyclic lipodepsipeptide from a widespread tropical Phoma sp., Bioorganic & Medicinal Chemistry, 2009, 17 (3), 1361-1366. Jayasuriya, H. , Herath, K.B. , Ondeyka, J.G. , Zink, D.L., Burgess, B. , Wang, J. , Singh, S.B., Structure of homoplatensimide A: a potential key biosynthetic intermediate of platensimycin isolated from Streptomyces platensis, Tetrahedron Letters, 2008, 49 (22), 3648-3651. Herath, K.B., Zhang, C., Jayasuriya, H., Ondeyka, J.G., Zink, D.L., Burgess, B., Wang, J., Singh, S.B.,Structure and semi synthesis of platensimide A, produced by Streptomyces platensis, Organic Letters, 2008, 10( 9), 1699-1702. Hiranthi Jayasuriya, Ziqiang, Guan, Anne W. Dombrowski, Gerald F. Bills, Jon D. Polishook, Rosalind G. Jenkins, Leslie Koch, Tami Crumley, Tamas Tamas, Michelle Dubois, Andrew Misura, Sandra J. Darkin-Rattray, Lynn Gregory and Sheo B. Singh, Isolation, structure and coccidiostat activity of coccidiostatin A, Journal of Natural Products, 2007, 70(8) 1364-1367. Hiranthi Jayasuriya, Kithsiri Herath, Chaowei Zhang, Deborah L. Zink, Mark Brower, Francis P.Gailliot, Joyce Greene, Gwyneth Birdsall, Jayashree Venugopal, Misti Ushio, Bruce Burgess, Greg Russotti, Andre Walker, Michelle Hesse, Anna Seeley, Beth Junker, Neal Connors, Oscar Salazar, Olga Genilloud, Kun Liu, Prakash Masurekar, John F.Barret and Sheo Singh, Isolation and structure elucidation of Thiazomycin, J. Antibiot. 2007, 60 (9) 554-564.
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Division of Animal Research Background B.S. – Jarvis Christian College Ph.D. – Howard University FDA Experience - 10 Years |
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Research Interests Molecular Biomarker Discovery and Molecular Assay Development Proposed Research Project for FDA Commissioner’s Fellow The MDR-1 gene encodes for P-gp, a transmembrane efflux protein that affects the absorption, distribution and elimination of certain drugs. P-gp is a member of the ATP-Binding Cassette (ABC) transport protein family, which are efflux pumps that remove select agents from within the cell. P-gp is part of a family of efflux transporters found along the intestinal tract, in the kidneys, biliary system, brain and other organs. A mutation in the MDR-1 gene is known to occur in several dog breeds. Most importantly, life threatening toxicity has been reported when certain P-gp substrates are administered to dogs that are known to be homozygous for the MDR-1 mutation. The goals of this Critical Path study are to explore the potential impact of multidrug resistance -1 (MDR-1) gene mutation on drug safety and effectiveness in the canine population; to define methods for determining drugs whose safety and/or effectiveness profile may necessitate studies in dogs known to be homozygous recessive for that mutation. Upon completion of this project, the Fellow would be expected to:
Select Recent Publications Yancy, H.F., Washington, J.D., Callahan, L., Mason J.A., Deaver, C.M., Farrell, D.E., Ha, T, Sespico, E., Falmlen, D., and Myers, M.J. Development, Evaluation, and Peer-Verification of a Rapid Real-Time PCR Method for the Detection of Animal Material. J Food Prot. (in Press). Yancy, H.F., Zemlak, T.S., Mason, J.A., Washington, J.D., Tenge, B.J., Nguyen, N.T, Barnett, J.D., Savary W.E., Hill, W.E., Moore, M.M., Fry, F.S., Randolph, S.C., Rogers, P.L., and Hebert, P.N. The Potential Use of DNA Barcodes in Regulatory Science: Applications of the Regulatory Fish Encyclopedia. J Food Prot. 2008 Jan;71(1):210-7. Yancy, H.F., Peters, S., Thompson, C.E., Mason, J.A., Littleton, G.K., and Day, A.A. Metastatic Progression and Gene Expression between African American and Caucasian Women with Breast Cancer. J Carcinog. 2007 May 1;6(1):8.
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