12th International Conference on Harmful Algae

INTERNATIONAL SOCIETY FOR THE STUDY OF HARMFUL ALGAE12 th <strong>International</strong> <strong>Conference</strong> on Harmful Algae, Copenhagen, Denmark, 4-8 September 2006and geographically restricted tooffshore waters between St.Petersburg and Naples. Kareniasp. was further restricted, presentonly at higher salinities in the Ft.Myers to Naples area. Thesepatterns of occurrence of thedifferent Karenia species throughoutthe blooms suggest that K. brevisoccupies the broadest ecologicalniche, with other species eitherspatially or temporally restricted.Management implications dependon impacts, toxins and toxicity ofdifferent strains. The first step isisolation of newly recorded species.O.22-01First evidence for the implicationof nitric oxide in Ciguatera FishPoisoningSession: O.22 - Toxicology 3Presentation time: 14.55 - 15:15S Pauillac, F Vernel-Pauillac, S Kumar-Roine, M-P Sauviat, E Benoit, MChinain, D LaurentInstitut Pasteur de Nouvelle-Calédonie,NOUMÉA, New CaledoniaThe involvement of the nitric oxide(NO) pathway in ciguatera fishpoisoning (CFP) has beeninvestigated, in vitro and in vivo, in aciguatoxin (CTX)/mouse model. Theinduction of inducible nitric oxidesynthase (iNOS) synthesis at themRNA level was kineticallymeasured using a real-time PCRprotocol based on the LightCycler®technology. CTX-pulsed Neuro-2acells (1 ng/mL) and peripheral bloodmononuclear cells from CTXinjectedmice (1ng/g), weredemonstrated to express iNOS in atime-dependent manner. Thisstrongly suggests that NO might beresponsible for certain ciguaterasymptoms (e.g. hypotension,allergenic effects and ChronicFatigue Syndrome) which could notbe solely explained by the activationof voltage-gated sodium channels.This hypothesis is supported by theobservation that the most currentlyused drugs for the treatment of CFPare free radical scavengers.In conclusion, the implication of NOin CFP paves the way for newtherapies for both occidental andtraditional medicines, together withnew CTXs detection and clinicaldiagnostic tools.O.22-02Implications of saxitoxins forpublic health and naturalresources in FloridaSession: O.22 - Toxicology 3Presentation time: 15:15 – 15.35JH Landsberg 1 , JP Abbott 2 , LJFlewelling 1 , PS Scott 1 , JL Wolny 21 FL Fish & Wildlife Conservation Comm.,ST. PETERSBURG, United States ofAmerica2 Florida Institute of Oceanography, ST.PETERSBURG, United States of AmericaIn early 2002, with the onset ofpuffer fish poisoning (PFP)originating from the Indian RiverLagoon (IRL), saxitoxin wasdiscovered in Florida andassociated with Pyrodiniumbahamense for the first time in theUnited States. Saxitoxins areusually associated with potentiallyfatal Paralytic Shellfish Poisoning(PSP), but prior to 2002, there wasno public health risk from PSP inFlorida. Since the detection ofsaxitoxins in puffer fish, the stateinitiated an intensive statewidemonitoring program to determineconcentrations and distribution ofsaxitoxins in biota. Because theyare immune to saxitoxins, puffer fishcan accumulate high toxinconcentrations in the muscle,making them an extreme threat toconsumers. Following FDA action80