Human Poisoning Research Articles

Regulatory role of oxidative stress in retrorsine – Induced apoptosis and autophagy in primary rat hepatocytes

Pyrrolizidine alkaloids (PAs) are a group of naturally occurring alkaloids widely present in plants. PAs are highly hepatotoxic and have been documented to cause many incidents of human and animal poisoning. Retrorsine (RTS) is a pyrrolizidine alkaloid (PA) derived from the Compositae Senecio, which has been shown to cause hepatotoxicity. Human liver poisoning occurs through the consumption of RTS-contaminated food, and animals can also be poisoned by ingesting RTS-containing toxic plants. The mechanism of RTS-induced liver toxicity is not fully understood. In this study, we demonstrated that RTS-induced oxidative stress plays a pivotal role in RTS-induced liver toxicity involving apoptosis and autophagy. The results showed that RTS treatment in the cultured Primary rat hepatocytes caused cytotoxicity and release of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in a time- and dose-dependent manner. Our study showed that treatment of RTS induced ROS and MDA (malondialdehyde, a lipid peroxidation marker) in the hepatocytes, and reduced antioxidant capacity (GSH content, SOD activity), suggesting RTS treatment caused oxidative stress response in the hepatocytes. Furthermore, we found that RTS induced apoptosis and autophagy in the hepatocytes, and RTS-induced apoptosis and autophagy could be alleviated by ROS scavenger N-acetylcysteine (NAC) and the MAPK pathway inhibitors suggesting ROS/MAPK signaling pathway plays a role in RTS induced apoptosis and autophagy. Collectively, this study reveals the regulatory mechanism of oxidative stress in RTS-induced apoptosis and autophagy in the hepatocytes, providing important insights of molecular mechanisms of hepatotoxicity induced by RTS and related pyrrolizidine alkaloids in liver. This mechanism provides a basis for the prevention and treatment of PA poisoning in humans and animals.

Purinergic Receptor Antagonists Inhibit Hemolysis Induced by Clostridium perfringens Alpha Toxin.

Clostridium perfringens alpha toxin (CPA), which causes yellow lamb disease in sheep and gas gangrene and food poisoning in humans, is produced by all types of C. perfringens and is the major virulence determinant of C. perfringens type A. CPA induces hemolysis in many species, including humans, murines, sheep and rabbits, through its enzymatic activity, which dissolves the cell membrane. Recent studies have shown that some pore-forming toxins cause hemolysis, which is achieved by the activation of purinergic receptors (P2). However, the relationship between P2 receptors and non-pore-forming toxin hemolysis has not been investigated. In the present study, we examined the function of P2 receptors in CPA toxin hemolysis and found that CPA-induced hemolysis was dependent on P2 receptor activation, and this was also true for Staphylococcus aureus β-Hemolysin, another non-pore-forming toxin. Furthermore, we use selective P2 receptor antagonists to demonstrate that P2X1 and P2X7 play important roles in the hemolysis of human and murine erythrocytes. In addition, we found that redox metabolism was mainly involved in CPA-induced hemolysis using metabolomic analysis. We further demonstrate that CPA activates P2 receptors and then activates NADPH oxidase through the PI3K/Akt and MEK1/ERK1 pathways, followed by the production of active oxygen to induce hemolysis. These findings contribute to our understanding of the pathological effects of CPA, clarify the relationship between P2 activation and non-pore-forming toxin-induced hemolysis, and provide new insights into CPA-induced hemolysis.

Co-administration of resveratrol rescued lead-induced toxicity in Drosophila melanogaster

Lead toxicity poses a significant environmental concern linked to diverse health issues. This study explores the potential mitigating effects of resveratrol on lead-induced toxicity in Drosophila melanogaster. Adult fruit flies, aged three days, were orally exposed to lead (60 mg/L), Succimer (10 mg), and varying concentrations of resveratrol (50, 100, and 150 mg). The investigation encompassed the assessment of selected biological parameters, biochemical markers, oxidative stress indicators, and antioxidant enzymes. Resveratrol exhibited a dose-dependent enhancement of egg-laying, eclosion rate, filial generation output, locomotor activity, and life span in D. melanogaster, significantly to 150 mg of diet. Most of the investigated biochemical parameters were significantly rescued in lead-exposed fruit flies when co-treated with resveratrol (p < 0.05). However, oxidative stress remained unaffected by resveratrol. The findings suggest that resveratrol effectively protects against lead toxicity in Drosophila melanogaster and may hold therapeutic potential as an agent for managing lead poisoning in humans.

Prevalence and Antibiotic Resistance Profile of Clostridium perfringens Isolated from Pork and Chicken Meat in Vietnam.

Clostridium perfringens is one of the most important zoonotic pathogens as it can cause food poisoning in humans and necrotic enteritis in both animals and humans. Meat, especially pork and chicken meat, is considered the main vehicle for the transmission of C. perfringens from animals to humans. The purpose of this study was to determine the prevalence, toxinotype, and antimicrobial resistance profile of C. perfringens isolated from pork and chicken meat sold in Vietnam. The isolation results showed that 15/50 (30%) of pork samples and 8/50 (16%) of chicken meat samples were contaminated with C. perfringens. The isolates exhibited their highest resistance rate to tetracycline (21/23; 91.30%) and clindamycin (10/23; 43.48%). On the contrary, their lowest resistance rates were observed in response to imipenem (2/23; 8.70%) and cefoxitin (1/23; 4.35%). In particular, 34.78% (8/23) of C. perfringens isolates were identified to be multidrug-resistant strains. The results of toxin genotyping indicated that all isolates were positive for the cpa gene and belonged to type A.

Bacillus cereus CwpFM induces colonic tissue damage and inflammatory responses through oxidative stress and the NLRP3/NF-κB pathway

Bacillus cereus (B. cereus) from cow milk poses a threat to public health, causing food poisoning and gastrointestinal disorders in humans. We identified CwpFM, an enterotoxin from B. cereus, caused oxidative stress and inflammatory responses in mouse colon and colonic epithelial cells. Colon proteomics revealed that CwpFM elevated proteins associated with inflammation and oxidative stress. Notably, CwpFM induced activation of the NLRP3/NF-κB signaling, but suppressed antioxidant NFE2L2/HO-1 expression in the intestine and epithelial cells. Consistently, CwpFM exposure led to cytotoxicity and ROS accumulation in Caco-2 cells in a dose-dependent manner. Further, NAC (ROS inhibitor) treatment abolished NLRP3/NF-κB activation due to CwpFM. Moreover, overexpression of Nfe2l2 or activation of NFE2L2 by NK-252 reduced ROS production and inhibited activation of the NLRP3/NF-κB pathway. Inhibition of NF-κB by ADPC and/or suppression of NLRP3 by MCC950 attenuated CwpFM-induced inflammatory responses in Caco-2 cells. Collectively, CwpFM induced oxidative stress and NLRP3/NF-κB activation by inhibiting the NFE2L2/HO-1 signaling and ROS accumulation, leading to the development of intestinal inflammation. Our data elucidate the role of oxidative stress and innate immunity in CwpFM enterotoxicity and contribute to developing diagnostic and therapeutic products for B. cereus-related food safety issues.

Characterization in the rat of the individual tendency to rely on alcohol to cope with distress and the ensuing vulnerability to drink compulsively.

Only some vulnerable individuals who recreationally drink alcohol eventually develop the compulsive drinking pattern that characterizes alcohol use disorder. A new frontier in biomedical research lies in understanding the neurobehavioural mechanisms of this individual vulnerability, a necessary step towards developing novel effective therapeutic strategies. Translational research has been hindered by the lack of valid, reliable and robust approaches that enable the study of the influence of the reliance on alcohol to cope with stress or self-medicate negative emotional states on the subsequent transition to alcohol use disorder. We have therefore developed a behavioural task in the rat that enables the investigation of the neural and cellular basis of the exacerbation of the vulnerability to develop compulsive alcohol drinking by the use of alcohol to develop an adjunctive, anxiolytic, polydipsic drinking behaviour in a schedule-induced polydipsia procedure. Hence, in our task, alcohol is introduced in the schedule-induced polydipsia context after several weeks of training with water so that rats are exposed to alcohol for the first time in a distressing context and learn to drink alcohol as a coping strategy. Capitalizing on this protocol, we have consistently been able to identify a subpopulation of rats that were unable to learn to cope with negative states by drinking water and relied on alcohol to do so. This maladaptive reliance on alcohol drinking to cope with distress has been shown to be associated with an exacerbation of the subsequent transition to compulsive drinking. Furthermore, these vulnerable rats reached blood alcohol levels comparable to that of intoxication in humans, thereby developing two key features of alcohol use disorder, namely excessive alcohol intake and compulsive drinking. Altogether, this behavioural task provides a novel and unique tool for the investigation of the neurobehavioural mechanisms underlying the exacerbation of the individual vulnerability to developing compulsive alcohol drinking by the use of alcohol as a strategy to cope with distress, and for the evaluation of the efficacy of potential therapeutic strategies in a personalized medicine approach. This procedure, which focuses on an understudied but key factor of the development of alcohol use disorder, may become widely used as it benefits the fields of alcohol, emotion regulation and stress, the interest in which has substantially increased since the evidence of a profound exacerbation of alcohol use and alcohol-related negative consequences by the distress and social isolation engendered by the various measures implemented worldwide in response to the COVID-19 pandemic.

Prevalence and antimicrobial susceptibility of Salmonella enteritidis and Salmonella typhimurium isolated from hen eggs and quail eggs in Karaj, Iran.

Different Salmonella serotypes are considered one of the most important food pathogens in the world. Poultry meat and eggs are the primary carriers of Salmonella in human populations. This study aimed to estimate the Salmonella enteritidis and Salmonella typhimurium contamination rates of retail hen and quail eggs in Karaj, Iran. Moreover, the antimicrobial resistance patterns of the strains were evaluated, and the efficiency of the standard culture method and multiplex polymerase chain reaction (m-PCR) were compared. In this descriptive cross-sectional study over 1 year (Jan-Dec 2022), 150 commercial and 150 backyard hen eggs and 300 commercial quail eggs, without cracks and fractures, were collected randomly from best selling groceries in Karaj city. All samples were examined for Salmonella contamination independently by standard culture and m-PCR approaches. A standard disc diffusion method was employed to assess the antimicrobial susceptibility of the strains against 18 antimicrobial agents. Out of 300 examined eggs, 2 S. enteritidis strains were isolated from the shell of backyard hen eggs. The same serotype was also detected in the contents of one of these two eggs. One S. typhimurium was isolated from the shell of a commercial hen egg. Overall, the Salmonella contamination of the shell and contents was 1% and 0.3%, respectively. Salmonella was not isolated from the eggshells or the contents of the quail eggs. There was complete agreement between the results of m-PCR and the standard culture methods. Among the 18 tested antibiotics, the highest resistance was recorded for colistin (100%), followed by nalidixic acid (75%). As most Salmonella spp. are associated with human food poisoning, continuous surveillance is required to effectively reduce the risk posed by contaminated poultry eggs. Furthermore, mandatory monitoring of antimicrobial use on Iranian poultry farms is recommended.

Environmental Factors Modulate Saxitoxins (STXs) Production in Toxic Dinoflagellate Alexandrium: An Updated Review of STXs and Synthesis Gene Aspects.

The marine dinoflagellate Alexandrium is known to form harmful algal blooms (HABs) and produces saxitoxin (STX) and its derivatives (STXs) that cause paralytic shellfish poisoning (PSP) in humans. Cell growth and cellular metabolism are affected by environmental conditions, including nutrients, temperature, light, and the salinity of aquatic systems. Abiotic factors not only engage in photosynthesis, but also modulate the production of toxic secondary metabolites, such as STXs, in dinoflagellates. STXs production is influenced by a variety of abiotic factors; however, the relationship between the regulation of these abiotic variables and STXs accumulation seems not to be consistent, and sometimes it is controversial. Few studies have suggested that abiotic factors may influence toxicity and STXs-biosynthesis gene (sxt) regulation in toxic Alexandrium, particularly in A. catenella, A. minutum, and A. pacificum. Hence, in this review, we focused on STXs production in toxic Alexandrium with respect to the major abiotic factors, such as temperature, salinity, nutrients, and light intensity. This review informs future research on more sxt genes involved in STXs production in relation to the abiotic factors in toxic dinoflagellates.

Procjena utjecaja matriksa na kvantifikaciju lipofilnih toksina u plodovima mora

Phycotoxin accumulation in seafood can cause human intoxication and significant economic losses in seafood-producing areas. To protect consumer safety, maximum permitted levels in bivalve molluscs have been set, with appropriate analytical methods for their determination and quantification. The reference method for lipophilic phycotoxins, commonly referred to as lipophilic toxins, is liquid chromatography tandem mass spectrometry (LCMS/MS method), where coeluting components from the matrix can affect the efficiency of ionisation, resulting in erroneous quantification. In this study, the matrix effect was evaluated using the slope ratio analysis method, which involves comparing the slopes of the calibration curves in the matrix with those in pure solvent. The extent of the matrix effect was investigated in mussels, oysters, queen scallops and ascidians. The study covered all phycotoxins under Regulation EU 853/2004 for which certified standards are commercially available, including unregulated pectenotoxin 2. The results indicated that all lipophilic toxins were susceptible to this effect when LC-MS/MS was used for their determination. Significant ion suppression was evident for most analytes in all matrices, except for okadaic acid and dinophysistoxin 2 in bivalves, where significant ion enhancement was demonstrated, and dinophysistoxin 1 in oyster and scallop extract where no significant effect on ionisation was observed. Further analysis revealed no significant differences between the slope of mussel matrix-matched calibration and that of other bivalve matrices. Given this minor difference, the mussel matrix-matched calibration curve could be applied to minimise the matrix effect and to quantify phycotoxins in bivalve matrices analysed here, with the exception of the okadaic acid group in ascidians, which requires matrix-matched calibration prepared with the blank extract of these mentioned species. Given the risks phycotoxins pose to human health, ongoing analytical method development is necessary in this field to properly control food safety and ensure consumer health.

Sudden peak in tetrodotoxin in French oysters during the summer of 2021: Source investigation using microscopy, metabarcoding and droplet digital PCR

Tetrodotoxin (TTX) is a potent neurotoxin causing human intoxications from contaminated seafood worldwide and is of emerging concern in Europe. Shellfish have been shown to contain varying TTX concentrations globally, with concentrations typically higher in Pacific oysters Crassostrea gigas in Europe. Despite many decades of research, the source of TTX remains unknown, with bacterial or algal origins having been suggested. The aim of this study was to identify potential source organisms causing TTX contamination in Pacific oysters in French coastal waters, using three different techniques. Oysters were deployed in cages from April to September 2021 in an estuary where TTX was previously detected. Microscopic analyses of water samples were used to investigate potential microalgal blooms present prior or during the peak in TTX. Differences in the bacterial communities from oyster digestive glands (DG) and remaining flesh were explored using metabarcoding, and lastly, droplet digital PCR assays were developed to investigate the presence of Cephalothrix sp., one European TTX-bearing species in the DG of toxic C. gigas. Oysters analysed by liquid chromatography-tandem mass spectrometry contained quantifiable levels of TTX over a three-week period (24 June–15 July 2021), with concentrations decreasing in the DG from 424 μg/kg for the first detection to 101 μg/kg (equivalent to 74 to 17 μg/kg of total flesh), and trace levels being detected until August 13, 2021. These concentrations are the first report of the European TTX guidance levels being exceeded in French shellfish. Microscopy revealed that some microalgae bloomed during the TTX peak, (e.g., Chaetoceros spp., reaching 40,000 cells/L). Prokaryotic metabarcoding showed increases in abundance of Rubritaleaceae (genus Persicirhabdus) and Neolyngbya, before and during the TTX peak. Both phyla have previously been described as possible TTX-producers and should be investigated further. Droplet digital PCR analyses were negative for the targeted TTX-bearing genus Cephalothrix.

In Vitro Characterization and Rescue of VX Metabolism in Human Liver Microsomes.

Venomous agent X (VX) is an organophosphate acetylcholinesterase (AChE) inhibitor, and although it is one of the most toxic AChE inhibitors known, the extent of metabolism in humans is not currently well understood. The known metabolism in humans is limited to the metabolite identification from a single victim of the Osaka poisoning in 1994, which allowed for the identification of several metabolic products. VX has been reported to be metabolized in vitro by paraoxonase-1 and phosphotriesterase, although their binding constants are many orders of magnitude above the LD50, suggesting limited physiologic relevance. Using incubation with human liver microsomes (HLMs), we have now characterized the metabolism of VX and the formation of multiple metabolites as well as identified a Food and Drug Administration-approved drug [ethylenediaminetetraacetic acid (EDTA)] that enhances the metabolic rate. HLM incubation alone shows a pronounced increase in the metabolism of VX compared with buffer, suggesting that cytochrome P450-mediated metabolism of VX is occurring. We identified a biphasic decay with two distinct rates of metabolism. The enhancement of VX metabolism in multiple buffers was assessed to attempt to mitigate the effect of hydrolysis rates. The formation of VX metabolites was shown to be shifted with HLMs, suggesting a pathway enhancement over simple hydrolysis. Additionally, our investigation of hydrolysis rates in various common buffers used in biologic assays discovered dramatic differences in VX stability. The new human in vitro VX metabolic data reported points to a potential in vivo treatment strategy (EDTA) for rescue in individuals that are poisoned though enhancement of metabolism alongside existing treatments. SIGNIFICANCE STATEMENT: Venomous agent X (VX) is a potent acetylcholinesterase inhibitor and chemical weapon. To date, we do not possess a clear understanding of its metabolism in humans that would assist us in treating those exposed to it. This study now describes the human liver microsomal metabolism of VX and identifies ethylenediaminetetraacetic acid, which appears to enhance the rate of metabolism. This may provide a potential treatment option for human VX poisoning.

Determination of Ethanol and Aromatics in Blood by Headspace Portable Gas Chromatography-Mass Spectrometry (HS-PGC-MS)

Ethanol abuse is increasingly becoming a global issue, adversely affecting both society and families. In blood alcohol concentration (BAC) detection, traditional techniques have long experimental cycles and harsh experimental conditions and often fail to produce timely results. Consequently, achieving swift and precise on-site detection of ethanol poisoning in humans poses a formidable challenge in analytical science. We designed a novel assay for swift on-site analysis of ethanol and BTEX (benzene, toluene, ethylbenzene, and xylene) poisoning in humans using a custom portable headspace injector (portable HS) and portable gas chromatography-mass spectrometry (portable GC-MS). This setup, known for its lightweight design and speed, allows on-site sampling and delivers rapid results. We established a calibration curve (R2 > 0.99) for ethanol in blood using portable gas chromatography-mass spectrometry (portable GC-MS). This on-site blood alcohol concentration (BAC) assay proves simpler than traditional methods, enabling rapid analysis of each sample within a short timeframe and requiring only a small blood volume (0.1 ml). In addition to our investigation on ethanol, we developed a portable method for detecting BTEX in blood. This method provides a favorable coefficient of determination (R2 > 0.99) for various substances, thereby broadening the utility of portable mass spectrometry in areas such as traffic inspection and forensic identification.

Development of a lateral flow immunochromatography assay for the detection of fluoroacetamide in blood samples

Fluoroacetamide (FAM) has been employed as a rodenticide for an extended duration, leading to a multitude of incidents involving human ingestion poisoning. Currently, FAMs have been prohibited by nations globally; however, there are still instances of their illegal usage. Conventional instrument methods are characterized by their time-consuming nature and complex operational procedures, rendering them inadequate for meeting urgent diagnostic needs in patients with acute FAM poisoning. Therefore, there is an immediate need to develop a prompt, user-friendly, and precise immunoassay method for the diagnosis of acute poisoning induced by FAM. A lateral flow immunochromatography assay (LFIA) was developed in this study for the visual detection of FAMs in blood samples, representing the first report of such an approach. The method exhibited a cut-off value of 0.5 mg/mL under the optimized conditions, enabling the entire FAM detection process in blood samples to be completed within a mere 8 min without any pretreatment requirements. Notably, the results were easily discernible by visual inspection alone. These results indicate that the developed LFIA holds great promise as a convenient and rapid diagnostic tool for FAM poisoning diagnosis, thereby offering valuable support for subsequent treatment strategies.

Harmful blooms caused by dinoflagellates in the Pacific of Guatemala (2019–2022)

Plankton studies in Guatemala are associated with the history of harmful algal blooms (HAB). An important event was observed in 1987, with 193 human poisonings due to shellfish consumption, of which 22 were lethal. The causative organism was Pyrodinium bahamense var. compressum. This species was reported again in November 2019 in the coastal Guatemalan Pacific. The species reached an abundance of 1 × 104 cells/L. In September 2020, the abundance of the Margalefidinium polykrikoides vegetative stage reached 1.24 × 106 cells/L, and its cysts 1.5 × 106 cells/L. Noctiluca scintillans proliferated (the first quantitatively estimated bloom of this species in Guatemala) in November 2020 and March 2021 (up to 1.2 × 106 cells/L). From January to December 2021, monthly monitoring was carried out in front of the Port of Quetzal at three sites (bottle and 25 μm mesh net samples). In April 2022, 11 cases of humans presenting symptoms of paralytic shellfish poisoning (PSP) were recorded in the western sector of the Guatemalan Pacific, in particular, in the municipality of Tiquisate in the department of Escuintla. From May 3 to 27, 2022, a HAB event caused the death of 4 and the poisoning of 34 humans in the departments near Mexico: Retalhuleu (Champerico), San Marcos (Tilapa) and Escuintla (Tiquisate, Buena Vista and Iztapa). The maximum saxitoxin (STX) concentration was determined in Retalhuleu (14,099 MU/100 g); until 7 July 2022, STX continued to be detected in Tilapa and Tiquisate (1,021 MU/100 g). The P. bahamense cells were observed in the stomach contents of the clam Tagelus sp. (Bivalvia: Solecurtidae).

Rapid detection of major enterotoxin genes and antibiotic resistance of Staphylococcus aureus isolated from raw milk in the Yazd province, Iran.

Raw milk is a nutrient-rich food, but it may harbour harmful bacteria, such as enterotoxigenic Staphylococcus aureus (S. aureus), which can cause staphylococcal food poisoning. Antibiotic resistance of S. aureus in raw milk can increase the risk of such infections, particularly among susceptible individuals. This study aimed to investigate the prevalence of enterotoxin genes a, d, g, i and j and the antibiotic resistance of S. aureus isolated from raw milk samples. During a 6-month sampling period, 60 raw milk specimens were obtained from diverse locations in Yazd province, Iran. Antibiogram profiling was conducted via the disc diffusion method. In addition, staphylococcal enterotoxin (SE) genes a, d, g, i, and j were detected through real-time PCR analysis. Bacteriological assays confirmed the presence of S. aureus in 11 samples (18.3%). All isolates demonstrated 100% resistance to penicillin G but exhibited sensitivity to vancomycin, while resistance to other antibiotics ranged from 36.4% to 45.5%. The prevalence of enterotoxin genes in these strains showed variable distribution, with sea being the predominant SE (45.5%), followed by sed (36.4%), seg (18.2), sej and sei (9.1% each). This study discovered the presence of multiple enterotoxins in S. aureus strains obtained from raw milk samples. These strains also demonstrated resistance to a variety of antibiotics. Since enterotoxigenic S. aureus is known to cause human food poisoning, monitoring food hygiene practices, especially during raw milk production, is critical.

Acute rotenone poisoning: A scoping review

ContextRotenone is a toxic chemical found in various plants, including some used as food. Rotenone poisoning can be fatal and there is no antidote. Mechanistically, rotenone inhibits mitochondrial complex I, leading to reduced ATP production, compensatory glycolytic upregulation and secondary lactate production, and oxidative stress. Our literature review examined acute rotenone poisoning in humans, including exposure scenarios, clinical presentations, and treatments. MethodsWe searched five databases for relevant literature from database inception through the search date: July 12, 2022, pairing controlled vocabulary and keywords for “rotenone” with terms relating to human exposures and outcomes, such as “ingestion,” “exposure,” and “poisoning.” We included all peer-reviewed reports found using the search terms where the full English text was available. Data abstracted included the number, age, weight, and sex of the exposed person(s), country where exposure happened, exposure scenario, ingestion context, estimated dose, clinical features, whether hospitalization occurred, treatments, and outcomes. ResultsAfter removing non-qualifying sources from 2,631 publications, we identified 11 case reports describing 18 victims, 15 of whom were hospitalized and five died. Most cases occurred in private quarters where victims unknowingly consumed rotenone-containing plants. Vomiting and metabolic acidosis occurred most commonly. Some patients exhibited impaired cardiopulmonary function. Supportive treatment addressed symptoms and included gastric lavage and/or activated charcoal to remove rotenone from the stomach, vasopressors for hypotension, mechanical ventilation for respiratory insufficiency, and sodium bicarbonate for acidosis. Some patients received N-acetylcysteine to counter oxidative stress. ConclusionsRotenone poisoning, though rare, can be fatal. Exposure prevention is impractical since rotenone is found in some plants used as food or pesticides. Cases may be under-diagnosed because symptoms are non-specific and under-reported in English-language journals since most cases occurred in non-English speaking countries. Treatments are supportive. Exploring antioxidant therapy in animal models of rotenone poisoning may be indicated considering rotenone's mechanism of toxicity.

Strain typing and antimicrobial susceptibility of Salmonella enterica Albany isolates from duck farms in South Korea

Salmonella enterica is distributed worldwide and is a common cause of bacterial food poisoning in humans and a serious public health problem. Although duck meat consumption has recently increased in Korea, studies on the epidemiological relationship between S. enterica contamination in duck farms are scarce. Salmonella enterica serovar Albany isolates recovered from duck farms were analyzed using two typing methods — IR Biotyper® (IRBT) and multilocus variable-number tandem repeat analysis (MLVA). The clustering results were compared with the epidemiological survey findings and the antimicrobial resistance profiles. From April 2019 to October 2020, 20 individual feces per farm from 5–6-week-old ducks were collected repeatedly from 105 duck farms. Salmonella spp. isolated from duck feces were identified using PCR and multilocus sequence typing to investigate the prevalence and distribution of the Salmonella serovars. The prevalence of S. enterica was 19%, and S. enterica Albany was the predominantly recovered isolate. The S. enterica Albany isolates underwent antimicrobial susceptibility testing to determine the minimum inhibitory concentration. MLVA and IRBT methods established relatedness and diversity among the S. enterica Albany isolates. Multidrug-resistant S. enterica Albany was distributed in all the farms. Antimicrobial resistance profiles reflected the duck farm characteristics and isolates recovered from the same farm showed an identical profile. Isolates repeatedly recovered from the same farm also showed identical IRBT clusters and MLVA groups. These findings suggest that the isolates remained on the duck farm and re-infected new duck flocks. Thus, proper cleaning and disinfection is required before the farms are repopulated.

The amnesic shellfish poisoning toxin, domoic acid: The tattoo of the king scallop Pecten maximus

Domoic acid (DA) is a potent neurotoxin produced by diatoms of the genus Pseudo-nitzschia and is responsible for Amnesic Shellfish Poisoning (ASP) in humans. Some fishery resources of high commercial value, such as the king scallop Pecten maximus, are frequently exposed to toxic Pseudo-nitzschia blooms and are capable of accumulating high amounts of DA, retaining it for months or even a few years. This poses a serious threat to public health and a continuous economical risk due to fishing closures of this resource in the affected areas. Recently, it was hypothesized that trapping of DA within autophagosomic-vesicles could be one reason explaining the long retention of the remaining toxin in P. maximus digestive gland. To test this idea, we follow the kinetics of the subcellular localization of DA in the digestive glands of P. maximus during (a) the contamination process — with sequential samplings of scallops reared in the field during 234 days and naturally exposed to blooms of DA-producing Pseudo-nitzschia australis, and (b) the decontamination process — where highly contaminated scallops were collected after a natural bloom of toxic P. australis and subjected to DA-depuration in the laboratory for 60 days. In the digestive gland, DA-depuration rate (0.001 day−1) was much slower than contamination kinetics. The subcellular analyses revealed a direct implication of early autophagy in DA sequestration throughout contamination (r = 0.8, P < 0.05), while the presence of DA-labeled residual bodies (late autophagy) appeared to be strongly and significantly related to slow DA-depuration (r = -0.5) resembling an analogous DA-tattooing in the digestive glands of P. maximus. This work provides new evidence about the potential physiological mechanisms involved in the long retention of DA in P. maximus and represents the baseline to explore procedures to accelerate decontamination in this species.

Epidemiology and Clinical Characteristics of Acute Plant Exposure in Patients Aged between 0 and 18 Years-A Six-Year Retrospective Study.

Exposure to plants accounts for approximately 5% of human poisoning cases reported by poison control centers in North America and Europe. The aim of this study was to investigate acute plant poisoning in patients aged 0-18 years admitted to a Romanian pediatric poison center, focusing on epidemiological and clinical aspects. A retrospective observational study was conducted between 2017 and 2022, analyzing medical records for demographic information, clinical features, biological findings, and outcomes. Statistical analysis was performed using Microsoft Excel. 71 patients (aged 7 months to 16 years) presented with acute plant poisoning. Most cases were unintentional (92.9%), peaking during the autumn season. Colocasia (18.3%), Dieffenbachia (9.8%), and Ricinus (5%) were the most frequently involved plants. Gastrointestinal symptoms, especially vomiting, predominated. The Poisoning Severity Score classified most cases as mild (52.1%), with no severe or fatal cases. The mean length of hospitalization was 1.8 days. Unintentional plant exposure, mainly in children under 5 years of age, accounted for more than 90% of cases. Gastrointestinal exposure and symptoms were prevalent, and treatment consisted mainly of symptomatic and supportive measures. Severe and fatal cases were rare, highlighting the generally favorable outcome and low incidence of severe poisoning in the pediatric population.

HYDRO-TELLURIC FLUOROSIS IN MOROCCO: TOXICITY, FLUOROPATHY AND CURRENT STATE OF PREVENTIVE ASPECTS

Prolonged exposure to fluorides causes chronic fluoride intoxication in humans and animals, which the main manifestation is, osteodental fluorosis. In Morocco, fluorosis affects a large number of animals, particularly ruminants, and constitutes a serious handicap in contaminated regions, both economically and in terms of health. It is identified by a change in the color, structure and orientation of the teeth, and by a change in the structure and texture of the bones. Regardless of the animal species affected, fluorosis appears after a relatively long period of exposure, from several months to several years, by disorders of phosphocalcic metabolism resulting in osteodental changes associated with various general symptoms. These lesions compromise the grip, chewing and movement of the animals, and thus cause malnutrition, a drop in productivity and sometimes may lead to death. These disturbances have the characteristic of being irreversible, since once installed, no treatment allows to eliminate them in a definitive way, prevention is therefore the only way to alleviate. In order to face this fluoride intoxication, farmers use mainly empirical methods, such as transhumance, the purchase of animals from fluoride free zones or their sale at a young age before the appearance of dental lesions. The reduction of ingestion by using water sources and feed with low fluoride content as well as the supplementation of minerals (Al, Mg, B, Ca) and vitamins (the case of vitamin C) to limit absorption, are also practiced. However, aluminum-based licking salt blocks and supplemented feed enriched with minerals and vitamins are no longer used due to the lack of financial means of some breeders and state financial support. While the preventive effects of calcium, magnesium and boron, have still not been the subject of clinical studies in ruminants. Decidedly, the lack of vulgarization and the socio-economic level of the population, as well as the lack of financial support, constitute the main obstacles in the ultimate goal of counteracting hydrotelluric fluorosis.