Determination of Palytoxins in Soft Coral and Seawater from a Home Aquarium. Comparison between Palythoa- and Ostreopsis-Related Inhalatory Poisonings.

Anecdotal reports exist of aquarium hobbyists that experienced severe respiratory distress and/or skin injury following cleaning operation of home aquaria containing Palythoa sp. soft corals. Hundreds of cases of respiratory illness and/or dermatitis have been recorded in proximity to the sea concomitantly with algal blooms of Ostreopsis spp. in the Mediterranean area. Both Palythoa spp. and Ostreopsis spp. contain congeners of palytoxin, a highly potent toxin whose inhalation hazard is however unknown. In this study, we demonstrate the presence of high levels of palytoxins (palytoxin and hydroxypalytoxin) in both soft coral and seawater from a home marine aquarium involved in the poisoning of a whole family. Due to the high toxin levels found in seawater, a procedure for a rapid and efficient determination of palytoxin in seawater was setup. A comparison of symptoms of Palythoa- and Ostreopsis-related inhalatory poisonings showed many similarities including fever, respiratory distress, nausea, and flu-like symptoms. From the chemical and symptomatological data reported herein it is reasonable to hold palytoxins responsible for respiratory disorders following inhalation. Although the exact mechanism through which palytoxin congeners exert their inhalatory toxicity is still unknown, this represents a step toward demonstrating that palytoxin congeners exert toxic effects through inhalation both in natural environments and in the surroundings of private and public aquaria.

Diarrhetic shellfish poisoning, Washington, USA, 2011.

Diarrhetic shellfish poisoning is a gastrointestinal illness caused by consumption of bivalves contaminated with dinophysistoxins. We report an illness cluster in the United States in which toxins were confirmed in shellfish from a commercial harvest area, leading to product recall. Ongoing surveillance is needed to prevent similar illness outbreaks.

[Can solar/geomagnetic activity restrict the occurrence of some shellfish poisoning outbreaks? The example of PSP caused by Gymnodinium catenatum at the Atlantic Portuguese coast].

Cyclic outbreaks of accumulation of paralytic shellfish poisoning (PSP) toxins in mussels attributed to Gymnodinium catenatum blooms displayed several of the highest inter-annual maxima coincidental with minima of the 11-year solar sunspot number (SSN) cycle. The monthly distribution of PSP was associated with low levels of the solar radio flux, a more quantitative approach than SSN for fluctuations in solar activity. A comparison between monthly distribution of PSP and other common biotoxins (okadaic acid (OA), dinophysistoxin-2 (DTX2) and amnesic shellfish poisoning (ASP) toxins) demonstrated that only PSP was significantly associated with low levels of radio flux (p < 0.01). PSP occurrence suggests a prior decline in solar activity could be required to act as a trigger, in a similar manner to a photoperiodic signal. The seasonal frequency increased towards autumn during the study period, which might be related to the progressive atmospheric cut-off of deleterious radiation associated with the seasonal change in solar declination, and might play an additional role in seasonal signal-triggering. PSP distribution was also associated with low levels of the geomagnetic index Aa. A comparison between monthly distribution of PSP and other common biotoxins, also demonstrated that only PSP was significantly associated with low levels of the Aa index (p < 0.01). In some years of SSN minima no significant PSP-outbreaks in mussels were detected. This was attributed to a steady rise in geomagnetic activity that could disrupt the triggering signal. Global distribution patterns show that hotspots for G. catenatum blooms are regions with deficient crustal magnetic anomalies. In addition to the variable magnetic field mostly of solar origin, static fields related to magnetized rocks in the crust and upper mantle might play a role in restricting worldwide geographic distribution.

Nairobi fly (Paederus) dermatitis in South Sudan: a case report.

A 28-year-old nursing student working in Juba, South Sudan, suddenly developed a rash over her mid-right clavicle. Beginning as a 10-cm-diameter erythematous patch with an irregular border, within 24 hours it had developed an increasingly gray, necrotic center, appearing similar to a burn. The patient was seen by 2 local physicians without a diagnosis being made. Ultimately, it was diagnosed as being caused by the toxic hemolymph, pederin, from the Nairobi fly (Paederus). The rash usually affects body parts not covered by clothing; healing time ranges from 7 to 28 days, usually with permanent skin discoloration. Preventive measures include typical antivector precautions, including bed nets, long-sleeve clothing, and avoiding fluorescent lights. If the beetles are found on the skin, brushing them off, rather than crushing them, avoids producing dermatitis. Treatment includes rapidly washing the affected area, applying cold, wet compresses, and possibly treating with antibiotics, steroids, and antihistamines.

Food poisoning outbreaks linked to mussels contaminated with okadaic acid and ester dinophysistoxin-3 in France, June 2009.

In June 2009, 11 outbreaks of food poisoning occurred in France, involving 45 individuals who had consumed mussels harvested in Vilaine Bay (Northwestern France). Because the toxic dinoflagellate Dinophysis spp. had been detected in the area from mid-May, okadaic acid (OA) and dinophysistoxins were suspected to be the cause of these outbreaks, although the weekly monitoring tests by mouse bioassay had been negative. With the help of the French reporting system for food-borne disease outbreaks, the detailed data on epidemiology, mussel consumption and complete product traceback, were collected for 11 individuals involved in three reported outbreaks. The batch of mussels identified as the source of these three outbreaks contained concentrations of toxins of the okadaic acid group that were approximately eight times higher than the European regulatory limit. Moreover, based on the consumption data available for the 11 cases, a lowest observable adverse effects level (LOAEL) was deduced. The LOAEL calculated from this study, although based on a very limited number of individuals, was in the same range, i.e. approximately 50 µg OA equivalents per person, as the LOAEL established by the European Food Safety Authority in 2006.

Accidental salinomycin intoxication in calves.

Twenty-four 10- to 16-week-old calves in a dairy herd in Birjand, Iran, inadvertently received an excessive dose of salinomycin mixed with barley grain. There was 58% mortality within 10 d. The calves had high serum AST, LDH, and CK activities; histopathologic lesions in myocardium, liver, and kidneys; and clinical signs associated with acute and congestive heart failure.

Marine toxins and the cytoskeleton: azaspiracids.

The azaspiracids (AZAs) are a group of marine phycotoxins discovered during the second half of the 1990s. Several cases of human intoxication due to the presence of AZAs in shellfish have been reported, with gastrointestinal symptoms. Toxicological studies in vivo and in vitro have revealed that various cell types are sensitive to AZA toxicity; however, the biological target of the toxin is still unknown. One of the in vitro signs of AZA toxicity is the alteration of the actin cytoskeleton arrangement, which is accompanied by changes in cell shape and loss of cell adherence to the substrate. Moreover, the cytoskeletal damage is irreversible after toxin withdrawal. Several other in vitro effects of AZAs have been described that could be related to cytoskeletal changes, such as E-cadherin degradation, caspase activation/apoptosis, membrane cholesterol reduction, or gene expression alterations, although evidence for a direct relationship between any of these effects and AZA-induced cytoskeletal damage is still nonexistent.

Detection of diarrheic shellfish poisoning and azaspiracid toxins in Moroccan mussels: comparison of the LC-MS method with the commercial immunoassay kit.

Diarrheic shellfish poisoning (DSP) is a recurrent gastrointestinal illness in Morocco, resulting from consumption of contaminated shellfish. In order to develop a rapid and reliable technique for toxins detection, we have compared the results obtained by a commercial immunoassay-"DSP-Check" kit" with those obtained by LC-MS. Both techniques are capable of detecting the toxins in the whole flesh extract which was subjected to prior alkaline hydrolysis in order to detect simultaneously the esterified and non esterified toxin forms. The LC-MS method was found to be able to detect a high level of okadaic acid (OA), low level of dinophysistoxin-2 (DTX2), and surprisingly, traces of azaspiracids 2 (AZA2) in mussels. This is the first report of a survey carried out for azaspiracid (AZP) contamination of shellfish harvested in the coastal areas of Morocco. The "DSP-Check" kit was found to detect quantitatively DSP toxins in all contaminated samples containing only OA, provided that the parent toxins were within the range of detection and was not in an ester form. A good correlation was observed between the two methods when appropriate dilutions were performed. The immunoassay kit appeared to be more sensitive, specific and faster than LC-MS for determination of DSP in total shellfish extract.

Iridoids as DNA topoisomerase I poisons.

The discovery of new topoisomerase I inhibitors is necessary since most of the antitumor drugs are targeted against type II and only a very few can specifically affect type I. Topoisomerase poisons generate toxic DNA damage by stabilization of the covalent DNA-topoisomerase cleavage complex and some have therapeutic efficacy in human cancer. Two iridoids, aucubin and geniposide, have shown antitumoral activities, but their activity against topoisomerase enzymes has not been tested. Here it was found that both compounds are able to stabilize covalent attachments of the topoisomerase I subunits to DNA at sites of DNA strand breaks, generating cleavage complexes intermediates so being active as poisons of topoisomerase I, but not topoisomerase II. This result points to DNA damage induced by topoisomerase I poisoning as one of the possible mechanisms by which these two iridoids have shown antitumoral activity, increasing interest in their possible use in cancer chemoprevention and therapy.

An unaddressed issue of agricultural terrorism: a case study on feed security.

In the late winter of 2003, a number of livestock animals in the Midwest were poisoned due the accidental contamination of a popular commercial feed with a lethal additive. Although all the evidence indicates this incident had no malicious or terrorist intent, it is informative as a case study highlighting potential security implications with respect to a terrorist event directed at U.S. agriculture.

[Dermatitis caused by 2 species of Paederus in south Iran]. / Dermatite due à deux espèces de Paederus au sud de l'Iran.

Paederus dermatitis is a pruritic, self-healing dermatitis, showing vesicle and squamose in ordinary cases. It is caused by rove beetles' Paederus hemolymph coming into contact with human skin. Paederus hemolymph contains the powerful pederin toxin. Paederus ilsae Bernhaurt and Paederus iliensis Coiffait are found in southern Iran and cause numerous cases of cutaneous lesions every year, chiefly in spring and summer. This is the first report describing the pathogen of Paederus in Iran. Dermatitis caused by these two species is the same except for duration and severity which are higher in P. ilsae. Clinical manifestations of the above mentioned species in human beings and Guinea pigs are different. Laboratory tests of pederin dissolved in ethanol is also part of the study. Complications arising from secondary infections, pederin stability and local treatment are also discussed.

Salinomycin-induced polyneuropathy in cats: morphologic and epidemiologic data.

In April 1996, an outbreak of toxic polyneuropathy in cats occurred in the Netherlands. All cats had been fed one of two brands of dry cat food from one manufacturer. Chemical analyses of these foods, stomach contents, and liver and kidney of affected cats revealed contamination with the ionophor salinomycin. Epidemiologic and clinical data were collected from 823 cats, or about 1% of the cats at risk. In 21 affected cats, postmortem examination was performed. The affected cats had acute onset of lameness and paralysis of the hindlimbs followed by the forelimbs. Clinical and pathologic examination indicated a distal polyneuropathy involving both the sensory and motor nerves.

[Salinomycin poisoning in a Polish stud horse]. / Salinomycinvergiftung in einem polnischen Pferdebestand.

24 cases of salinomycin poisoning in horses occurring recently in Silesia are discussed. All of these horses, used for riding-purposes, were fed with concentrate containing 61 mg/kg salinomycin as faulty prepared by the manufacturer. Each horse received approximately two to three kilograms of this forage. All horses developed severe clinical signs of intoxication. Despite therapy eight horses died within three to six days. Ten others became recumbent and had to be euthanased. Only six horses survived. Clinical and laboratory examinations were performed and are discussed. Laboratory examination of blood included red blood cell count, haematocrit, concentration of haemoglobin, enzyme activities of ASAT, ALAT and AP, also levels of urea, creatinine, sodium, potassium, magnesium, calcium and inorganic phosphor. Blood gas was also analysed. The dominating laboratory results were very high enzyme levels and alkalosis. The most characteristic clinical change appeared as paralysis of the hindlimbs.

[Epidemic of nutritional polyneuropathy in the cat. Final report of the investigational team]. / Epidemie van alimentaire polyneuropathie bij de kat. Eindverslag onderzoeksteam.

In June 1996 companion animal practitioners received a report prepared by the Faculty Investigative Team on the outbreak of polyneuropathy among cats, and at the end of August a 'definitive' bulletin was circulated by Spillers Petfoods. The coccidiostatic drug salinomycin, which was present in the vitamin premix supplied by a third party, was considered the cause of the neuropathy. The investigative team is of the opinion that all veterinary practitioners in the Netherlands should receive a conclusive report about the epidemic because of the unique nature of the epidemic, which despite its sudden outbreak could be well documented, and because aspects of the affair merit the attention of veterinary practitioners.

Development of a protein phosphatase-based assay for the detection of phosphatase inhibitors in crude whole cell and animal extracts.

Diarrhetic shellfish poisoning (DSP) is a serious and globally widespread phytoplankton-related seafood illness. Although DSP is rarely life-threatening, it causes incapacitating diarrhea and vomiting with no known medical treatments. In addition, phytoplankton producing DSP toxins have been identified in temperate coastal waters worldwide, and their numbers may be increasing as a result of coastal eutrophication. The toxic effects of the major DSP toxins, okadaic acid and dinophysistoxin-1 (35-methylokadaic acid), appear to originate from their inhibitory activity against a family of structurally related serine/threonine protein phosphatases (PSPases). In particular, the inhibition of essential PSPases (e.g. PP1 and PP2A) has catastrophic consequences in most eukaryonic cells. Exploiting the potent inhibitory property of the DSP toxins, we have developed an enzyme-based assay (PP2A assay) capable of detecting both okadaic acid and dinophysistoxin-1 in nanogram amounts. The assay employs purified PP2A, which has an extremely high affinity for both DSP toxins. This provides the PP2A assay with a level of sensitivity comparable to, or surpassing, that of most monoclonal antibody probes. To evaluate the PP2A assay as a means of detecting contaminated shellfish, a series of spike recovery experiments was conducted. The findings from these studies suggest that the PP2A assay has the potential for development into a rapid and relatively simple method for detecting PSPase inhibitors in crude extracts produced from shellfish.