Beginning in the fall of 1996, there was evidence of increasing activity of Pfiesteria and Pfiesteria-like dinoflagellates in estuarine areas on the easter shore of the Chesapeake Bay, as manifested by characteristic """"""""punched out"""""""" lesions and erratic behavior in fish. Persons exposed to affected waterways reported problems with confusion, """"""""forgetfulness,"""""""" headaches, and skin and respiratory irritation; on neuropsychologic evaluation, exposed persons had significant impairments in learning, with 75% of persons with a high level of exposure to affected waterways having scores on learning measures which were below the 2nd percentile for age- and educationally-stratified population norms. Based on these observations, we hypothesize that toxins produced by Pfiesteria-like dinoflagellates present in Maryland waters cause specific impairments in human learning and memory. We propose to further explore this hypothesis (and related questions about Pfiesteria) in a comprehensive interwoven program incorporating 6 projects and three supporting core activities. Projects include: 1) Neuropsychologic studies, focusing on defining the nature and extent of learning and memory impairments in affected persons; 2) Molecular genetic studies, directed toward genetic identification and characterization of the Pfiesteria species present in Maryland; 3) Studies of mechanisms underlying toxin expression by the dinoflagellate; 4) Comparative medicine studies, exploring the responses of fish to specific toxins, and the relationship of these response to observations in humans; 5) Neurotoxicologic studies, looking at the responses to toxin preparations in tissue culture and animals models, and evaluating possible mechanisms underlying these responses; and 6) Epidemiologic studies, to link human health effects with specific environmental exposures. Projects will be supported by administrative; clinical; and dinoflagellate culture, bioassay, and toxin production core activities; the latter core will include BSL3 laboratory facilities. Pfiesteria, with its propensity for killing fish and its human health effects, has generated great public concern and had a profound economic impact on affected area. Data from the proposed studies are essential if we are to understand the real risks associated with this microorganisms and develop rational interventions to protect public health.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Research Program Projects (P01)
Project #
5P01ES009563-04
Application #
6382266
Study Section
Special Emphasis Panel (ZES1-LKB-A (P))
Program Officer
Tyson, Frederick L
Project Start
1998-08-17
Project End
2003-07-31
Budget Start
2001-08-01
Budget End
2002-07-31
Support Year
4
Fiscal Year
2001
Total Cost
$1,278,963
Indirect Cost
Name
University of Maryland Baltimore
Department
Public Health & Prev Medicine
Type
Schools of Medicine
DUNS #
003255213
City
Baltimore
State
MD
Country
United States
Zip Code
21201
Drgon, Tomas; Saito, Keiko; Gillevet, Patrick M et al. (2005) Characterization of ichthyocidal activity of Pfiesteria piscicida: dependence on the dinospore cell density. Appl Environ Microbiol 71:519-29
Kazeto, Yukinori; Place, Allen R; Trant, John M (2004) Effects of endocrine disrupting chemicals on the expression of CYP19 genes in zebrafish (Danio rerio) juveniles. Aquat Toxicol 69:25-34
Miller, Todd R; Hnilicka, Kristin; Dziedzic, Amanda et al. (2004) Chemotaxis of Silicibacter sp. strain TM1040 toward dinoflagellate products. Appl Environ Microbiol 70:4692-701
Goto-Kazeto, Rie; Kight, Katherine E; Zohar, Yonathan et al. (2004) Localization and expression of aromatase mRNA in adult zebrafish. Gen Comp Endocrinol 139:72-84
Choich, J A; El-Nabawi, A; Silbergeld, E K (2004) Evidence of histamine receptors in fish brain using an in vivo [14C]2-deoxyglucose autoradiographic method and an in vitro receptor-binding autoradiographic method. Environ Res 94:86-93
Miller, Todd R; Belas, Robert (2004) Dimethylsulfoniopropionate metabolism by Pfiesteria-associated Roseobacter spp. Appl Environ Microbiol 70:3383-91
Miller, Todd R; Belas, Robert (2003) Pfiesteria piscicida, P. shumwayae, and other Pfiesteria-like dinoflagellates. Res Microbiol 154:85-90
Saito, Keiko; Drgon, Tomas; Robledo, Jose A F et al. (2002) Characterization of the rRNA locus of Pfiesteria piscicida and development of standard and quantitative PCR-based detection assays targeted to the nontranscribed spacer. Appl Environ Microbiol 68:5394-407
Trant, J M; Gavasso, S; Ackers, J et al. (2001) Developmental expression of cytochrome P450 aromatase genes (CYP19a and CYP19b) in zebrafish fry (Danio rerio). J Exp Zool 290:475-83
Kazeto, Y; Ijiri, S; Place, A R et al. (2001) The 5'-flanking regions of CYP19A1 and CYP19A2 in zebrafish. Biochem Biophys Res Commun 288:503-8

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