Distribution of toxins

Not all these polyether occur together in the same shellfish samples. OA was the major toxin in the mussel specimens from most of the European countries (42), while DTXl was the major toxin in mussel in Japan and in Sogndal, Norway (43). Scallops in Japan show the most complicated toxin profile. Furthermore, the relative ratio of the toxins varied regionally, seasonally, and annually. Pectenotoxins were detected, however, only in Japanese shellfish. Distribution of toxins is summarized in Table I. 

Pasteels JM, Termonia A, Daloze D, Windsor DM (2000) Distribution of toxins in Chrysomeline leaf beetles possible taxonomic inferences. In Furth DG (ed) Special topics in leaf beetle biology. Proc 5th Symposium on the Chrysomelidae. Pensoft Publishers, Sofia Moscow, p 261... 

Pharmacology The mode of entry and distribution of toxins in the body Biochemistry The metabolism and interaction of toxins with cell components Physiology The effect of toxins on body organs... 

Pharmacology (the mode of entry and distribution of toxins in the body)... 

In this study we have used a combination of scanning electron microscopy, transmission electron microscopy, immunoelectron microscopy and immunocytochemistry to determine the earliest pathological changes in skeletal muscle following the inoculation of notexin and to study the distribution of toxin binding sites. 

The actions of toxins may be classified according to the our current perspective of ion channel function. Channels open, or gate , in response to a range of stimuli , variables that perturb the population distribution among a set of possible channel... 

Tetrodotoxin (TTX) and saxitoxin (STX) are potent sodium channel blockers that are found in phylogenetically diverse species of marine life. The wide distribution of TTX and STX has resulted in speculation that bacteria are the source of these toxins. Recently, investigators have reported isolation of marine bacteria, including Vibrio Alteromonas, Plesiomonas, and Pseudomonas species, that produce TTX and STX. This chapter details the methods and results of research to define bacterial sources of TTX and STX. 

Palytoxin isolated from zoanthids Palythoa spp. is known to be extremely lethal (0.5 fig/kgy mouse, i.p.) and to have the most complicated natural product structure (Figure 4) ever elucidated (13,14). The toxin was later revealed to be a potent tumor promoter (15). Yet, health risks due to the toxin have remained unclear, as the zoathids are the most unlikely organisms to be regarded as foodstuff. Recently, however, data are being compiled to indicate the wide distribution of this toxin among marine biota. 

Of particular interest in brevetoxin research are the diagnosis of intoxication and identification of brevetoxins and their metabolites in biological fluids. We are investigating the distribution and fate of radiolabeled PbTx-3 in rats. Three model systems were used to study the toxicokinetics and metabolism of PbTx-3 1) rats injected intravenously with a bolus dose of toxin, 2) isolated rat livers perfused with toxin, and 3) isolated rat hepatocytes exposed to the toxin in vitro. 

These studies represent the first report of the metabolism of brevetoxins by mammalian systems. PbTx-3 was rapidly cleared from the bloodstream and distributed to the liver, muscle, and gastrointestinal tract. Studies with isolated perfused livers and isolated hepatocytes conflrmed the liver as a site of metabolism and biliary excretion as an important route of toxin elimination. [ H]PbTx-3 was metabolized to several compounds exhibiting increased polarity, one of which appeared to be an epoxide derivative. Whether this compound corresponds to PbTx-6 (the 27,28 epoxide of PbTx-2), to the corresponding epoxide of PbTx-3, or to another structure is unknown. The structures of these metabolites are currently under investigation. 

Wilson, A.D., Bland, P.W. and Stokes, C.R. (1990) Expression and distribution of la antigen in the murine small intesine influence of environment and cholera toxin. International Archives of Allergy and Applied Immunology 91, 348—353. 

Walker SJ, Llewellyn GC, Lillehoj EB, Dashek WV. Uptake and distribution of aflatoxin Bj in excised, soybean roots and toxin effects on root elongation. JEnviron ExperBot 1984 24 113-122. 

One role of cyanobacterial allelochemicals may be to alter the motility and distribution of competing photoautotrophs. In a recent study, Kearns and Hunter (2001) examined the effects of toxic metabolites from the filamentous cyanobacterium A. flos-aquae on a unicellular phytoplankton species, Chlamydomonas rein-hardtii. A. flos-aquae synthesizes both microcystins as well as anatoxins, providing the authors with an ecologically relevant opportunity to assess the individual and combinatorial effects of these toxins on an alga. 

Disch A, Schwender J, Muller C, Lichtenthaler HK, Rohmer M (1998) Distribution of the meval-onate and glyceraldehyde phosphate/pyruvate pathways for isoprenoid biosynthesis in unicellular algae and the cyanobacterium Synechocystis PCC 6714. Biochem J 333 381-388 Dittmann E, Wiegand C (2006) Cyanobacterial toxins - occurrence, biosynthesis and impact on human affairs. Mol Nutr Food Res 50 7-17... 

The risk of CFP and the severity of disease symptoms may be associated with population sensitivity to the disease and a variety of other conditions. These conditions include the location where the fish was caught, the amount and parts of the fish eaten, fish species, fish size, seasonal fish distribution patterns, types of toxins present, and local ecologic reef disturbances (Lange et ah, 1992). 

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