Human Poisoning Research Articles

DIVERSITY OF POTENTIALLY TOXIC BENTHIC DINOFLAGELLATES IN INDONESIAN WATERS

Ciguatera Fish Poisoning (CFP) is a syndrome caused by ciguatoxin-producing benthic dinoflagellate, which are typically attached to macroalgae. The toxin is responsible for the human poisoning symptom observed after the consumption of contaminated reef fish. Research on the composition and abundance of benthic dinoflagellate on macroalgae had already conducted within the 2010 - 2015 at several coral reef areas in Indonesian waters, such as Weh Island - Aceh, Belitung Island, Lampung Bay, Seribu Islands, and Lombok Island. This study reviewed all the references concern on benthic dinoflagellate researches in Indonesia, with aims to raise awareness on the presence of potentially toxic benthic dinoflagellates in Indonesian waters, also to create an inventory of the species discovered. The study revealed four of the six genera which are potentially toxic, namely Amphidinium, Gambierdiscus, Ostreopsis, and Prorocentrum. The Prorocentrum cells were identified in a larger number than any other genera in all the sampling locations. The relatively high number of benthic dinoflagellates were observed in Lampung Bay and Seribu Islands, which might be due to the high level of human activities. These findings are essential to compile a database on the CFP-causing species and to monitor the affected areas, specifically in highly populated locations or tourist sites.

Neurotoxicological profile of the hallucinogenic compound 25I-NBOMe

4-Iodo-2,5-dimethoxy-N-(2-methoxybenzyl)phenethylamine (25I-NBOMe) is a new psychoactive substance with strong hallucinogenic properties. Our previous data reported increased release of dopamine, serotonin, and glutamate after acute injections and a tolerance development in the neurotransmitters release and rats’ behavior after chronic treatment with 25I-NBOMe. The recreational use of 25I-NBOMe is associated with severe intoxication and deaths in humans. There is no data about 25I-NBOMe in vivo toxicity towards the brain tissue. In this article 25I-NBOMe-crossing through the blood–brain barrier (BBB), the impact on DNA damage, apoptosis induction, and changes in the number of cortical and hippocampal cells were studied. The presence of 25I-NBOMe in several brain regions shortly after the drug administration and its accumulation after multiple injections was found. The DNA damage was detected 72 h after the chronic treatment. On the contrary, at the same time point apoptotic signal was not identified. A decrease in the number of glial but not in neural cells in the frontal (FC) and medial prefrontal cortex (mPFC) was observed. The obtained data indicate that 25I-NBOMe passes easily across the BBB and accumulates in the brain tissue. Observed oxidative DNA damage may lead to the glial cells’ death.

Efficacy of Fumonisin Esterase in Piglets as Animal Model for Fumonisin Detoxification in Humans: Pilot Study Comparing Intraoral to Intragastric Administration

Fumonisins, a group of highly prevalent and toxic mycotoxins, are suspected to be causal agents of several diseases in animals and humans. In the animal feed industry, fumonisin esterase is used as feed additive to prevent mycotoxicosis caused by fumonisins. In humans, a popular dosage form for dietary supplements, with high patient acceptance for oral intake, is capsule ingestion. Thus, fumonisin esterase provided in a capsule could be an effective strategy against fumonisin intoxication in humans. To determine the efficacy of fumonisin esterase through capsule ingestion, two modes of application were compared using piglets in a small-scale preliminary study. The enzyme was administered intraorally (in-feed analogue) or intragastrically (capsule analogue), in combination with fumonisin B1 (FB1). Biomarkers for FB1 exposure; namely FB1, hydrolysed FB1 (HFB1) and partially hydrolysed forms (pHFB1a and pHFB1b), were measured both in serum and faeces using a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, and toxicokinetic parameters were calculated. Additionally, the serum sphinganine/sphingosine (Sa/So) ratio, a biomarker of effect, was determined using LC-MS/MS. A significantly higher Sa/So ratio was shown in the placebo group compared to both esterase treatments, demonstrating the efficacy of the esterase. Moreover, a significant decrease in serum FB1 area under the concentration-time curve (AUC) and an increase of faecal HFB1 AUC were observed after intraoral esterase administration. However, these effects were not observed with statistical significance after intragastric esterase administration with the current sample size.

Human poisonings by neurotoxic phycotoxins related to the consumption of shellfish: study of cases registered by the French Poison Control Centres from 2012 to 2019

Context In June 2019, a paralytic shellfish poisoning (PSP) case related to the consumption of mussels contaminated by saxitoxins at a concentration below the regulatory threshold came to the attention of the French Agency for Food, Environmental and Occupational Health and Safety (ANSES). This pointed to probable undetected human cases of poisoning by neurotoxic phycotoxins. Methods We conducted a retrospective study of poisoning cases by bivalve shellfish (oysters, mussels and scallops) recorded by the French Poison Control Centres (PCC) from 2012 to 2019. All medical records were reviewed by a toxicologist. Cases that could be related to neurotoxic phycotoxins were selected and described. Diagnosis was based on symptoms compatible with ingestion of contaminated shellfish and on contamination data for the shellfish production area (analysed by the French Research Institute for Exploitation of the Sea, Ifremer), or notifications to the European Rapid Alert System for Food and Feed when the origin of the shellfish was known. Results Among the 619 shellfish poisoning cases recorded by the PCCs from 2012 to 2019, 22% (n = 134) had reported at least one neurological symptom (headache, dizziness or paraesthesia). Review of medical records for the 134 patients led to suspicion of 14 cases of PSP and one case of amnesic shellfish poisoning. Five patients experienced persistent neurological symptoms. Marine toxins were not tested for in the blood or urine of these patients. Conclusion This retrospective identification of cases strongly suspected of being related to neurotoxic phycotoxins led ANSES, PCCs and Ifremer to develop a specific questionnaire and to recommend actions to take when neurological symptoms related to shellfish consumption are reported to a PCC. Daily monitoring of shellfish poisoning cases registered in the national PCCs database was also implemented in order to rapidly detect any suspicious cases, alert the competent authorities, and warn the general population.

2020 webPOISONCONTROL data summary

IntroductionIncreasing use of the internet for health information has decreased utilization of traditional telephone-based poison centers in the United States. webPOISONCONTROL®, a browser-based tool and app was launched to meet the growing demand for online, personalized recommendations for human poison exposures. This study was conducted to characterize webPOISONCONTROL cases and highlight its potential for real-time monitoring of poisoning. MethodsCase data for all completed, nonduplicated public cases entered in 2020 were analyzed using a custom Qlik Sense dashboard. ResultsOf the 156,202 cases, 52.9% occurred in children younger than 4 years. Most cases (109,057, 69.8%) were initially triaged to home, 28.4% were advised to call Poison Control, and 1.7% were referred to the ED. Follow-up was available for 33.3% of home-triaged cases; 1.7% of those had a change in triage recommendation.Pharmaceuticals were implicated in 41.5% of cases (nonpharmaceuticals in 58.5%). Ingestion was the most common route (88.4%, 138,012). One-time double dose therapeutic error cases were implicated in 17,901 cases (27.6% of pharmaceutical cases). Cosmetics (13.9%) and cleaning substances (12.9%) were the most frequent substance categories. Melatonin was the most frequently implicated generic substance (4.5% of cases). Most (72.0%) cases had no effect (21.4%), a minor effect (3.9%) or were minimally toxic with unknown outcome (46.7%). There were no deaths, 17 major outcomes (0.01%), and 26.7% of cases had potentially toxic exposures with no outcome determination.In 2020, webPOISONCONTROL handled 7.3% as many human poison exposure cases as were reported to U.S. phone-based poison centers. Online cases are skewed towards younger ages (53% in children younger than 4 years vs 37% of phone-based cases) and towards nonpharmaceuticals (58.5% vs 43.5%). Near real-time data visualizations enabled detection of COVID-19-related increases in exposures to hand sanitizers and cleaners, illustrating the public health surveillance and hazard detection capabilities of webPOISONCONTROL. ConclusionThe webPOISONCONTROL tool provides a safe, quick and fully-automated alternative to those who are unable or unwilling to use the telephone to call a traditional poison center.

Differences in caecal microbiota composition and Salmonella carriage between experimentally infected inbred lines of chickens

BackgroundSalmonella Enteritidis (SE) is one of the major causes of human foodborne intoxication resulting from consumption of contaminated poultry products. Genetic selection of animals that are more resistant to Salmonella carriage and modulation of the gut microbiota are two promising ways to decrease individual Salmonella carriage. The aims of this study were to identify the main genetic and microbial factors that control the level of Salmonella carriage in chickens (Gallus gallus) under controlled experimental conditions. Two-hundred and forty animals from the White Leghorn inbred lines N and 61 were infected by SE at 7 days of age. After infection, animals were kept in isolators to reduce recontamination of birds by Salmonella. Caecal contents were sampled at 12 days post-infection and used for DNA extraction. Microbiota DNA was used to measure individual counts of SE by digital PCR and to determine the bacterial taxonomic composition, using a 16S rRNA gene high-throughput sequencing approach.ResultsOur results confirmed that the N line is more resistant to Salmonella carriage than the 61 line, and that intra-line variability is higher for the 61 line. Furthermore, the 16S analysis showed strong significant differences in microbiota taxonomic composition between the two lines. Among the 617 operational taxonomic units (OTU) observed, more than 390 were differentially abundant between the two lines. Furthermore, within the 61 line, we found a difference in the microbiota taxonomic composition between the high and low Salmonella carriers, with 39 differentially abundant OTU. Using metagenome functional prediction based on 16S data, several metabolic pathways that are potentially associated to microbiota taxonomic differences (e.g. short chain fatty acids pathways) were identified between high and low carriers.ConclusionsOverall, our findings demonstrate that the caecal microbiota composition differs between genetic lines of chickens. This could be one of the reasons why the investigated lines differed in Salmonella carriage levels under experimental infection conditions.

OnabotulinumtoxinA for the treatment of headache: an updated review.

Botulinum toxin (BT) is a neurotoxin produced by Clostridium botulinum, a gram-positive anaerobic bacterium. Systemic human intoxication from BT following oral ingestion results in acute and life-threatening muscle paralysis called botulism. BT has a wide scope of therapeutic uses, including conditions associated with increased muscle tone, smooth muscle hyperactivity, salivation, sweating, and allergies, as well as for cosmetic purposes. Several commercial forms of BT are available for medical use, including Botox (onabotulinumtoxinA). Multiple studies have found evidence of an analgesic effect of onabotulinumtoxinA and demonstrated the benefits of its use for the treatment of various chronic pain disorders. In this review, we provide an update on the use of onabotulinumtoxinA for the treatment of headache disorders.

Tannic Acid Inhibits Salmonella enterica Serovar Typhimurium Infection by Targeting the Type III Secretion System.

Salmonella enterica serovar Typhimurium (S. Typhimurium) is a zoonotic pathogen that can cause food poisoning and diarrhea in both humans and animals worldwide. The Salmonella pathogenicity island (SPI) genes encoded type III secretion system (T3SS) is important for S. Typhimurium invasion and replication in host cells. Due to the increasing problem of antibiotic resistance, antibiotic treatment for clinical Salmonella infection has gradually been limited. Anti-virulence inhibitors are a promising alternative to antibiotics because they do not easily induce bacterial antibiotic resistance. Here, we systematically evaluated the therapeutic effect of tannic acid (TA) on Salmonella-infected mice and elucidated its anti-infection mechanism. TA treatment improved the survival rate of S. Typhimurium-infected mice and alleviated cecum pathological lesions. In addition, TA inhibited S. Typhimurium invasion to HeLa cells without affecting their growth. Further studies showed that TA could inhibit the expression of sipA and sipB. This inhibition may be implemented by inhibiting the transcription of key regulatory and structural genes of the T3SS. This study provides an alternative anti-virulence strategy for Salmonella infection treatment.

Dinophysis spp. abundance and toxicity events in South Cornwall, U.K.: Interannual variability and environmental drivers at three coastal sites

Dinophysis is a genus of dinoflagellates with the potential to cause diarrhoeic Shellfish Poisoning (DSP) in humans. The lipophilic toxins produced by some species of Dinophysis spp. can accumulate within shellfish flesh even at low cell abundances, and this may result in the closure of a shellfish farm if toxins exceed the recommended upper limit. Over the period 2014 to 2020 inclusive there were several toxic events along the South West coast of U.K. related to Dinophysis spp. The Food Standards Agency (FSA) monitoring programme measure Dinophysis cell abundances and toxin concentration within shellfish flesh around the coasts of England and Wales, but there are few schemes routinely measuring the environmental parameters that may be important drivers for these Harmful Algal Blooms (HABs). This study uses retrospective data from the FSA monitoring at three sites on the south Cornwall coast as well as environmental data from some novel platforms such as coastal WaveRider buoys to investigate potential drivers and explore whether either blooms or toxic events at these sites can be predicted from environmental data. Wind direction was found to be important in determining whether a bloom develops at these sites, and low air temperature in June was associated with low toxicity in the shellfish flesh. Using real time data from local platforms may help shellfish farmers predict future toxic events and minimise financial loss.

Design of Middle School Chemistry Experiment Simulation System Based on Apriori Algorithm

Aiming at the safety problems of toxic, flammable and explosive chemicals used in middle school chemical experiments, such as human poisoning, skin corrosion, fire or explosion caused by improper experimental operation, a virtual simulation method of chemical experiments based on unity is proposed. Due to the need to analyze and compare the data in chemical experiments, summarize the experimental characteristics and data relevance. Therefore, based on the Apriori algorithm, this method deeply excavates the data obtained in the chemical experiment, uses Maya to model the experimental environment, uses unity to design the interactive functions in the experimental process, and uses visual effect graph technology, shader graph technology and other methods to realize the special effect simulation of various chemical experiments. With this method, the virtual simulation prototype system of middle school chemistry experiment is developed. The example shows that this method can vividly and realistically reproduce the simulation effect of chemical experiment, find the correlation between the experimental data, classification, properties and the overall characteristics of the data, describe and predict the development trend of the data, so as to make better use of these data to provide support for chemical experiment, and not only solve the problems of poisoning, corrosion of skin and It also solves the problems that it is difficult to scientifically compare data and find data relevance in traditional chemical experiments.

Cytotoxicity of the Fusarium mycotoxin deoxynivalenol on mammalian and avian cell lines

Trichothecenes are mycotoxins that occur in grains and can lead to acute and chronic poisoning in animals and humans. Deoxynivalenol (DON) is a type B trichothecene affecting protein synthesis, immune system, leading to brain, blood and kidney disorders. The aim of this work was to evaluate in vitro the cytotoxicity and the pathological effects of DON in short-term experiments on cells from non-tumour and tumour permanent cell lines and to compare their sensitivity. Cell cultivation of BALB/c 3T3, DEC 99, MDA-MB-231, MCF-7 and Hela cells was performed. Quantitative and qualitative methods evaluating cytotoxicity on the base of statistical and morphological analyses for determining the impact on the viability and proliferative activity were used: Neutral Red Uptake (NRU) cytotoxicity test, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test and fluorescence microscopy. The cytotoxic effect of DON was assessed after an exposure period of 24 h. DON treatment induced significant alterations in the growth and morphology of the cells, involving early and late apoptosis and necrosis signs. Statistically significant decrease of the viability of all cell lines was established at concentrations of DON starting from 1.9 µg/mL to 3.7 µg/mL, the mean IC50 concentrations were calculated. According to the IC50 values the hierarchical order of cell lines’ sensitivity was determined.

Thymol Disrupts Cell Homeostasis and Inhibits the Growth of Staphylococcus aureus.

Staphylococcus aureus (S. aureus) is a typical kind of symbiotic bacteria, which can cause human pneumonia, food poisoning, and other health problems. Nowadays, the corresponding prevention and treatment have been a hot issue of general concern in related research areas. However, the mechanism of action against S. aureus is not well understood. In order to tackle such problem, we used broth microdilution to discuss the antibacterial effect of 5-methyl-2-isopropylphenol and determine inhibitory concentration. In addition, membrane potential and lipid peroxidation levels were also measured under experimental conditions. The experimental results suggested that 300 μg/mL thymol might cause cell membrane damage and decrease of NADPH concentration and increase of NADP+ and lipid peroxidation level. In such condition, thymol has the potential to result in membrane rupture and disruption of cellular homeostasis. Furthermore, we also found that NOX2 is involved in maintaining the balance of NADPH/NADP+ in cells. Finally, our work confirms that NOX2 is a potential downstream target for thymol in the cell. Such target can provide specific guidance and recommendations for its application in antifungal activity. Meanwhile, our study also provides a new inspiration for the molecular mechanism of thymol's bacteriostatic action.

Profile of work accidents caused by venomous animals in Brazil's Federal District from 2009 to 2019.

IntroductionThe high numbers of accidents involving venomous animals in tropical countries is a major public health problem and has prompted the World Health Organization to place them on its list of neglected tropical diseases. The Notifiable Diseases Information System shows that the number of notifications of accidents involving venomous animals increases every year. In Brazil, accidents involving venomous animals are the number one cause of human intoxications. The public health importance of accidents and their consequential importance for workers is clearly illustrated by the more than 100,000 accidents and almost 200 deaths that occur annually.ObjectivesTo observe and analyze the profile of accidents involving venomous animals in Brazil’s Federal District.MethodsA retrospective descriptive case series study of data from four databases containing information on accidents involving venomous animals. In addition to analyzing each one, they were also compared to each other.ResultsA total of 11,376 accidents involving venomous animals from 2009 to 2019 were registered in the Federal District. There were 363 occupational accidents and zero deaths in the period. There were discrepancies between each of the databases analyzed.ConclusionsSubnotification and discrepancies should be better evaluated and subsequently resolved by the managers of each database. Actively seeking information and better organization of the organs responsible for database management are possible solutions to the current problems.

Tetrodotoxin in live bivalve mollusks from Europe: Is it to be considered an emerging concern for food safety?

Tetrodotoxins (TTXs) are a group of potent neurotoxins named after the Tetraodontidae fish family (pufferfish). TTXs have been reported in several animal taxa, both terrestrial and marine. The ingestion of TTX-contaminated flesh can cause serious neurotoxic symptomatology and can eventually lead to death. Traditionally, TTXs have been associated with Asian countries, in particular with pufferfish consumption. However, they have also been reported in bivalve mollusks farmed in the Pacific area and, recently, in European seas. In Europe, different countries have reported TTXs, especially those bordering the Mediterranean Sea. As a consequence, in 2017 the European Food Safety Authority (EFSA) released an opinion with reference to TTX present in marine gastropods and bivalves, proposing a safety limit of 44 µg/kg TTXs in shellfish meat, below which no adverse effects should be observed in humans. Nevertheless, this limit has been exceeded on many occasions in European shellfish and, while for bivalves there have been no registered human intoxications, that is not the case for marine gastropods. However, TTXs have not yet been included in the list of marine biotoxins officially monitored in live bivalve mollusks within the European Union (EU). Thus, the aims of this manuscript are to discuss the increasing occurrence of TTXs in live bivalve mollusks from European sea waters, to acknowledge the still ongoing knowledge gaps that should be covered and to stimulate constructive debate on the eventuality of adopting a shared regulatory context, at least in the EU, for monitoring and managing this potential threat to food safety.

Tetramine Contents in the Salivary Glands from 16 Species of Marine Carnivorous Gastropods Collected along Japanese Coasts

Tetramine (tetramethyl ammonium ion), a neurotoxin, is present at high levels in the salivary glands of buccinid gastropods and is responsible for human intoxication due to consumption of the gastropods. We used LC-MS/MS to examine the tetramine contents of salivary glands from 16 species of carnivorous gastropods collected along Japanese coasts. Tetramine was detected in all specimens except for Babylonia japonica. High levels of tetramine were detected in whelks, Neptunea lamellosa (1,380-9,410 μg/g of salivary gland) and N. purpurea (1,190-7,400 μg/g of salivary gland). Although consumption of N. lamellosa is well-known cause of foodborne tetramine poisoning, it was newly discovered that N. purpurea has tetramine. In addition, we found 7 other species of gastropods containing tetramine: Siphonalia cassidariaeformis (117-135 μg/g), S. fusoides (204 μg/g), Buccinum inclytum (2.94-3.40 μg/g), and B. aniwanum (0.700 μg/g) of the family Buccinidae, and Fusinus perplexus (397 μg/g), F. ferrugineus (105 μg/g), and F. forceps salisburyi (67.5 μg/g) of the family Fasciolariidae. The present study, together with previous studies, shows that gastropods with salivary glands containing more than 1,000 μg tetramine/g of salivary gland, including the genus Neptunea as well as Fusitriton oregonesis and Hemifusus tuba, carry a high risk of tetramine poisoning, and their salivary glands should be removed before consumption to prevent food poisoning.

Shielding Analysis of Metal Hydride-based Materials for Both Neutron and Gamma Rays Using Monte Carlo Simulation

Radiation causes damage to the human body, the environment, and electronic equipment. Shielding against neutron and gamma rays is particularly difficult because of their strong ability to penetrate materials. Conventional gamma ray shields are typically made of materials containing Pb. However, they pose problems in that Pb is a heavy metal, and human poisoning and/or pollution can result from the manufacturing, use, and disposal of these materials. In addition, neutron rays are shielded by materials rich in H2 or concrete. In the case of the latter, the manufacturing cost is high. Thus, it is necessary to develop a new multilayer structure that can shield against both neutron and gamma rays. We set up a simulation model of a multilayered structure consisting of metal hydrides and heavy metals, and then evaluated the simulations using Monte Carlo N-Particle Transport Code. Monte Carlo simulation is an accurate method for simulating the interaction between radiation and materials, and can be applied to the transport of radiation particles to predict values such as flux, energy spectrum, and energy deposition. The results of the study indicated the multilayer structure of ZrH2, U, and W could shield both neutron and gamma rays, thus showing potential as a new shielding material to replace Pb and concrete.

Identification of Histamine in Fish and Fish Products in Poland During 2014-2018.

IntroductionHistamine is one of the most important and toxic biogenic amines which may be present in food and may cause food poisoning in humans when contained at a high level. It is produced during bacterial decarboxylation of histidine in fish muscles. The aim of the study was to investigate the presence of histamine in fish and fish products available in Poland during 2014–2018.Material and MethodsA total of 421 samples of raw (248), smoked (107), canned (50), and marinated fish (16) were analysed by high-performance liquid chromatography with diode array detection.ResultsHistamine was detected in 14.1% samples of raw fish, 29% of smoked fish, 22% of canned fish and 93.8% of marinated fish in concentrations ranging from 3.4 to 156.4 mg/kg. Content of this amine above 100 mg/kg was found in four samples: raw Atlantic salmon, smoked European sprat and two samples of marinated Atlantic herring.ConclusionThe study showed that fish and fish products on the Polish market generally meet the food safety criteria for histamine and are safe for consumers.

Assessment of glufosinate-containing herbicide exposure: A multi-center retrospective study.

Exposure to glufosinate ammonium, an herbicide used worldwide, can cause CNS and respiratory toxicities. This study aimed to analyze acute human glufosinate ammonium poisoning. This multicenter retrospective cohort study involved five medical institutes affiliated with the Chang Gung Memorial Hospital system. Patients with glufosinate ammonium exposure visiting the emergency department (ED) between January 2008 and December 2020 were included. In total, 95 patients were enrolled. Compared to exposure via the non-oral route, patients exposed orally (n = 61) had lower GCS scores, higher mortality rates, and longer hospital lengths of stay (P-value: <0.001, 0.002, and < 0.001, respectively). In the subgroup analysis among oral exposure patients, the survival group had a lower amount of estimated glufosinate ingestion than the non-survival group (10.5 [3.4-27] vs. 40.5 [27-47.3] g, P-value: 0.022), lower rate of substance co-exposure (9 [19.6%] vs. 10 [66.7%] P-value: 0.001), and lower rate of paraquat co-exposure (0 [0%] vs. 7 [46.7%] P < 0.001) compared with the mortality group. In the orally-exposed and non-paraquat co-exposure patients (n = 54), age > 70 years and GCS score < 9 at triage presented a high sensitivity (100.00%, 95% CI: 63.06-100.00%) and medium specificity (58.70%, 95% CI: 43.23-73.00%) in predicting mortality. Old age, change in consciousness, and paraquat co-exposure were associated with higher mortality in human glufosinate poisoning. Age > 70 years and GCS score < 9 at triage could be predictors of mortality in patients with acute oral glufosinate poisoning.

Cross-Genus "Boot-Up" of Synthetic Bacteriophage in Staphylococcus aureus by Using a New and Efficient DNA Transformation Method.

Staphylococcus aureus is an opportunistic pathogen that causes a wide range of infections and food poisoning in humans with antibiotic resistance, specifically to methicillin, compounding the problem. Bacteriophages (phages) provide an alternative treatment strategy, but these only infect a limited number of circulating strains and may quickly become ineffective due to bacterial resistance. To overcome these obstacles, engineered phages have been proposed, but new methods are needed for the efficient transformation of large DNA molecules into S. aureus to "boot-up" (i.e., rescue) infectious phages. We presented a new, efficient, and reproducible DNA transformation method, NEST (non-electroporation Staphylococcus transformation), for S. aureus to boot-up purified phage genomic DNA (at least 150 kb in length) and whole yeast-assembled synthetic phage genomes. This method was a powerful new tool for the transformation of DNA in S. aureus and will enable the rapid development of engineered therapeutic phages and phage cocktails against Gram-positive pathogens. IMPORTANCE The continued emergence of antibiotic-resistant bacterial pathogens has heightened the urgency for alternative antibacterial strategies. Phages provide an alternative treatment strategy but are difficult to optimize. Synthetic biology approaches have been successfully used to construct and rescue genomes of model phages but only in a limited number of highly transformable host species. In this study, we used a new, reproducible, and efficient transformation method to reconstitute a functional nonmodel Siphophage from a constructed synthetic genome. This method will facilitate the engineering of Staphylococcus and Enterococcus phages for therapeutic applications and the engineering of Staphylococcus strains by enabling transformation of higher molecular weight DNA to introduce more complex modifications.

Chemodiversity of Brevetoxins and Other Potentially Toxic Metabolites Produced by Karenia spp. and Their Metabolic Products in Marine Organisms.

In recent decades, more than 130 potentially toxic metabolites originating from dinoflagellate species belonging to the genus Karenia or metabolized by marine organisms have been described. These metabolites include the well-known and large group of brevetoxins (BTXs), responsible for foodborne neurotoxic shellfish poisoning (NSP) and airborne respiratory symptoms in humans. Karenia spp. also produce brevenal, brevisamide and metabolites belonging to the hemi-brevetoxin, brevisin, tamulamide, gymnocin, gymnodimine, brevisulcenal and brevisulcatic acid groups. In this review, we summarize the available knowledge in the literature since 1977 on these various identified metabolites, whether they are produced directly by the producer organisms or biotransformed in marine organisms. Their structures and physicochemical properties are presented and discussed. Among future avenues of research, we highlight the need for more toxin occurrence data with analytical techniques, which can specifically determine the analogs present in samples. New metabolites have yet to be fully described, especially the groups of metabolites discovered in the last two decades (e.g tamulamides). Lastly, this work clarifies the different nomenclatures used in the literature and should help to harmonize practices in the future.