Diversity of marine biotoxins in the near-shore ocean area: presence of a palytoxin-like entity at Barber's Point Harbor, Oahu.

The presence of palytoxin or palytoxin-like compounds in fish extracts has been presented in this study. The hemolytic assay with sheep erythrocytes demonstrated the occurrence of hemolytic factors in fish extracts of Hawaiian reef fish from Barber's Point, Oahu. The rabbit anti-palytoxin inhibition assay with fish extracts and sheep erythrocytes demonstrated that palytoxin or its congener contributed to the lysis of sheep erythrocytes. From these results, it was concluded that sheep erythrocyte hemolysis was caused by palytoxin or palytoxin-like factors present in the fish extracts. Moderate correlation (R2) between mouse toxicity and sheep erythrocyte hemolysis was shown with 50 microg (R2 = 0.48) and 100 microg (R2 = 0.45) extracts. An inverse correlation of R2 = 0.64 was shown between hemolysis and MIA endpoint.

The biological assessment of flora and fauna as standards for changes in the near-shore ocean environment: a study of Barbers Point Harbor.

The biological assessments of the flora and fauna in the near-shore ocean environment, specifically Barbers Point Harbor (BPH), demonstrate the usefulness of these biological analyses for evaluation of the changes occurring following man-made excavation for expansion of the harbor. The study included identification and enumeration of macroalgae and dinoflagellates and analyses of herbivores and carnivores in four areas within the perimeter of the harbor and the north and south entrances into the harbor. Numbers of macroalgae varied between 1994 and 1999 surveys, with significant decrease in numbers in stations C, D and E. Stations A and B were similar between 1994 and 1999 with a slight increase in 1999. The significant differences were shown with the appearance of Gambierdiscus toxicus (G toxicus) in 1999 among the algae in stations A and B. Assessment of herbivores and carnivores with the immunological membrane immunobead assay using monoclonal antibody to ciguatoxin and related polyethers demonstrated an increase in fish toxicity among the herbivore from 1994-1999 (22% increase) with a decrease (22%) in non-toxic fish. This was also demonstrated in the carnivores, but to a lesser degree. It is suggested that the biological analyses of the flora and the fauna of the near-shore ocean environment are appropriate to assess the changes that occur from natural and man-made alterations.

Evidence for palytoxin as one of the sheep erythrocyte lytic in lytic factors in crude extracts of ciguateric and non-ciguateric reef fish tissue.

The occurrence of palytoxin or its congener in fish extracts has been presented in this study. The presences of hemolytic factors in fish extracts of Hawaiian reef fish and their implication in ciguatera poisoning have been shown by the sheep erythrocyte assay. By use of the anti-palytoxin inhibition assay with fish extracts and sheep red blood cell (RBC), it was shown that palytoxin was one of the major factors in the lysis of sheep erythrocytes. Ouabain, an antagonist of palytoxin for the Na+/K+ ATPase receptor on RBC, also showed inhibition of sheep RBC lysis by fish extracts. From these results, it was concluded that, in part, palytoxin and other palytoxin-related, hemolysin-like factors in fish extracts were responsible for sheep cell hemolysis.

Stereospecific taurine conjugation of the trans-OH metabolite (active metabolite) of CS-670, a new 2-arylpropionic acid nonsteroidal anti-inflammatory drug, in dogs.

CS-670, (+/-)-2-[4-(2-oxocyclohexylidenemethyl)phenyl]propionic acid, is a novel derivative of 2-arylpropionic acid non-steroidal anti-inflammatory drugs (profen NSAIDs). The major urinary metabolite of this drug from dogs was isolated and its chemical structure was determined by MS and NMR spectroscopy. The metabolite was identified as a taurine conjugate of the trans-OH form (trans-OH-taurine) which was first generated by stereoselective reduction of the double bond and the carbonyl function of the CS-670 molecule. The taurine conjugate was excreted in urine as the main metabolite, regardless of the optical configuration of CS-670 administered [2R)-enantiomer: 47.2% of the dose, (2S)-enantiomer: 70.9% of the dose]. The trans-OH-taurine was hydrolyzed by refluxing it in 6 N HCl without racemization. The released trans-OH was derivatized to diastereoamides with (+)-(R)-1-(1-naphthyl)ethylamine to examine the stereochemical properties of the 2-arylpropionic acid side chain. It was found that the configuration of the 2-carbon of the trans-OH-taurine was almost entirely (S). As the CoA thioesters are obligate intermediates for amino acid conjugation, the results suggest that the (2S)-enantiomer of the trans-OH metabolite serves as a substrate for canine acyl CoA ligase (EC 6.2.1.3) as well as the (2R)-enantiomer, but only the CoA thioester with a (2S)-configuration is a substrate for taurine N-acyl transferase. It is interesting to note that these results are not consistent with the chiral inversion mechanism by which the (2R)-enantiomers of profen NSAIDs are stereospecifically converted to CoA thioester intermediates.

Synthesis and thromboxane synthetase inhibitory activity of di- or tetrahydrobenzo[b]thiophenecarboxylic acid derivatives.

1-Imidazolylalkyl-substituted di- or tetrahydrobenzo[b]thiophenecarboxylic acid derivatives and related compounds were synthesized from tetrahydrobenzo[b]thiophene derivatives (1 or 4) in order to study the structure-activity relationships of the inhibition of thromboxane A2 synthetase in vitro. Sodium 2-(1-imidazolylmethyl)-4,5-dihydrobenzo[b]thiophene-6-carboxylate (26) and 2-(1-imidazolylmethyl)-4,5,6,7-tetrahydrobenzo[b]thiophene-6-carbo xylic acid hydrochloride (28) showed the most potent and specific activity in vitro for thromboxane A2 synthetase inhibition.

Synthesis and antiinflammatory activity of [(cycloalkylmethyl)phenyl]acetic acids and related compounds.

[(Cycloalkylmethyl)phenyl]acetic acid derivatives and related compounds were synthesized to test their antiinflammatory and analgesic activities. Some of the compounds in this series were found to have good activity in the carrageenan edema test. Among them, sodium 2-[4-[(2-oxocyclopentyl)methyl] phenyl]propionate dihydrate (15) and 2-[4-[(2-oxocyclohexylidene)methyl]phenyl]propionic acid (13b) showed potent analgesic and antiadjuvant arthritis activities with excellent antipyretic properties.