A Rapid Method for the Detection of Diarrhetic Shellfish Toxins and Azaspiracid Shellfish Toxins in Washington State Shellfish by Liquid Chromatography Tandem Mass Spectrometry.

Background: Diarrhetic shellfish toxins (DSTs) in domestic shellfish and azaspiracids (AZAs) in imported products are emerging seafood safety issues in the United States. In addition to causing gastrointestinal illnesses, some of these toxins are also carcinogenic and genotoxic. Efficient analytical strategies are needed for their monitoring in U.

Ultrahigh-Performance Hydrophilic Interaction Liquid Chromatography with Tandem Mass Spectrometry Method for the Determination of Paralytic Shellfish Toxins and Tetrodotoxin in Mussels, Oysters, Clams, Cockles, and Scallops: Collaborative Study.

Background: An ultrahigh-performance LC (UHPLC)-tandem MS (MS/MS) method for determination of paralytic shellfish poisoning toxins and tetrodotoxin (TTX) in bivalve molluscs was developed. To be used for regulatory testing, it needed to be validated through collaborative study.

Objective: The aim was to conduct a collaborative study with 21 laboratories, using results to assess method performance.

Validation Study of MaxSignal Histamine Enzymatic Assay for the Detection of Histamine in Fish/Seafood.

Bioo Scientific Corp. has developed a rapid enzymatic quantitative assay for the determination of histamine in seafood. Fresh/frozen tuna, canned tuna, pouched tuna, and frozen mahi mahi samples were used for the validation study under the specific guidelines of the AOAC Research Institute Performance Tested MethodsSM program.

Dexmedetomidine for Sedation During Noninvasive Ventilation in Pediatric Patients.

Objectives: To describe the use of dexmedetomidine for sedation in a large cohort of nonintubated children with acute respiratory insufficiency receiving noninvasive ventilatory support.

Design: Single-center, retrospective, observational cohort study.

Setting: A large quaternary-care PICU.

Remifentanil for Sedation of Children With Traumatic Brain Injury.

Objective: To determine whether remifentanil would provide adequate sedation while allowing frequent and reproducible neurologic assessments in children admitted to the pediatric intensive care unit (PICU) with traumatic brain injury (TBI) during mechanical ventilation.

Design: Retrospective review.

Setting: Tertiary care PICU.

Validation of the Biofish-300 HIS Enzymatic Biosensor for the Detection of Histamine in Fishery Products.

The Biofish-300 HIS method is a simple, reliable, and specific enzymatic biosensor for the detection of histamine. This technology is highly specific and selective and allows quantification of histamine in fishery products (fresh/frozen and processed) in a short time frame (2-3 min). Histamine in raw tuna, raw mackerel, raw sardine, raw anchovy, boiled tuna, canned tuna in water, canned tuna in oil, canned mackerel in tomato sauce, canned pickled sardine, and canned salted anchovy was analyzed using a water-based extract.

Potential Threats Posed by Tetrodotoxins in UK Waters: Examination of Detection Methodology Used in Their Control.

Tetrodotoxin is a neurotoxin responsible for many human fatalities, most commonly following the consumption of pufferfish. Whilst the source of the toxin has not been conclusively proven, it is thought to be associated with various species of marine bacteria. Whilst the toxins are well studied in fish and gastropods, in recent years, there have been a number of reports of tetrodotoxin occurring in bivalve shellfish, including those harvested from the UK and other parts of Europe.

Potential threats posed by new or emerging marine biotoxins in UK waters and examination of detection methodology used in their control: brevetoxins.

Regular occurrence of brevetoxin-producing toxic phytoplankton in commercial shellfishery areas poses a significant risk to shellfish consumer health. Brevetoxins and their causative toxic phytoplankton are more limited in their global distribution than most marine toxins impacting commercial shellfisheries. On the other hand, trends in climate change could conceivably lead to increased risk posed by these toxins in UK waters.

Flow cytometric-membrane potential detection of sodium channel active marine toxins: application to ciguatoxins in fish muscle and feasibility of automating saxitoxin detection.

Ciguatoxins are potent neurotoxins with a significant public health impact. Cytotoxicity assays have allowed the most sensitive means of detection of ciguatoxin-like activity without reliance on mouse bioassays and have been invaluable in studying outbreaks. An improvement of these cell-based assays is presented here in which rapid flow cytometric detection of ciguatoxins and saxitoxins is demonstrated using fluorescent voltage sensitive dyes.

Scombroid poisoning: a review.

Scombroid poisoning, also called histamine fish poisoning, is an allergy-like form of food poisoning that continues to be a major problem in seafood safety. The exact role of histamine in scombroid poisoning is not straightforward. Deviations from the expected dose-response have led to the advancement of various possible mechanisms of toxicity, none of them proven.

Flow cytometric detection of saxitoxins using fluorescent voltage-sensitive dyes.

By virtue of their ability to block depolarization of nerve cells, the saxitoxins exert the toxic effects associated with paralytic shellfish poisoning and allow for their detection through various methodologies. When veratridine-induced depolarization is followed using voltage-sensitive fluorescent dyes, the presence of these toxic blocking agents can be observed as a decrease in fluorescence of dye-treated nerve cells. Detection using flow cytometry provides for selection of the most responsive population of cultured mouse neuroblastoma (Neuro 2a) cells thereby enhancing assay sensitivity and this approach can be accomplished in real time.

Marine and freshwater toxins.

In a very busy and exciting year, 2005 included First Action approval of a much needed official method for paralytic shellfish toxins and multiple international toxin symposia highlighted by groundbreaking research. These are the first-year milestones and activities of the Marine and Freshwater Toxins Task Force and Analytical Community. Inaugurated in 2004 and described in detail in last year's General Referee Report (1) this international toxins group has grown to 150 members from many regions and countries.

Insulin dynamically regulates calmodulin gene expression by sequential o-glycosylation and phosphorylation of sp1 and its subcellular compartmentalization in liver cells.

O-glycosylation and phosphorylation of Sp1 are thought to modulate the expression of a number of genes in normal and diabetic state. Sp1 is an obligatory transcription factor for constitutive and insulin-responsive expression of the calmodulin gene (Majumdar, G., Harmon, A.

Committee on Natural Toxins and Food Allergens. Marine and freshwater toxins.

There have been major developments this past year in the Marine and Freshwater Toxins topic area (formerly Phycotoxins). These include AOAC approval and inauguration of a new AOAC Presidential Task Force on Marine and Freshwater Toxins to accelerate methods validation, and the appointment of several new Topic Advisors. A joint FAO/IOC/WHO group addressing biotoxins in molluscan bivalves is also relevant to this report and to the new Task Force.

Detection of paralytic shellfish poison by rapid cell bioassay: antagonism of voltage-gated sodium channel active toxins in vitro.

Although cytotoxicity assays provide several advantages over mouse bioassays, sodium channel-blocking marine toxins, such as those associated with paralytic shellfish poison (PSP), require prolonged incubation periods of 24-48 h. This is in marked contrast to in vitro detection of sodium channel-enhancing marine toxins such as ciguatoxins or brevetoxins which can be accomplished in as few as 4-6 h. We developed a modified PSP cell bioassay that is as rapid as in vitro methods for sodium channel-enhancing toxins.