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Staphylococcus aureus, a common pathogen, is capable of producing a significant array of toxins and can develop biofilms or small colony variants (SCVs) to evade detection by the immune system and resist the effects of antibiotics. Its ability to persist for extended periods within host cells has led to increased research interest. This review examines the process of internalization of S. aureus, highlighting the impact of its toxins and adhesion factors on host cells. It elucidates the intricate interactions between them and the host cellular environment, thereby offering potential strategies for the treatment and prevention of S. aureus infections. [ABSTRACT FROM AUTHOR]

Animal venoms are a focus of research due to the hazards they represent and to their relationship to evolution and ecology, pharmacology, biodiscovery, and biotechnology. Venoms have evolved multiple times in Lepidoptera, mostly as defensive adaptations that protect the larval life stages. While venoms are always produced in structures derived from cuticle and setae, they are diverse in their composition and bioactivity, reflecting their multiple evolutionary origins. The most common result of envenomation by lepidopterans is pain and inflammation, but envenomation by some species causes fatal hemorrhagic syndromes or chronic inflammatory conditions in humans or veterinary pathologies such as equine amnionitis and fetal loss. The handful of lepidopteran venom toxins that have been characterized includes coagulotoxins from Lonomia obliqua (Saturniidae) and pain-causing cecropin-like peptides from Doratifera vulnerans (Limacodidae). However, our knowledge of lepidopteran venoms remains comparatively poor, with further studies required to yield a clear picture of the evolution, composition, and function of venoms produced by Lepidoptera. [ABSTRACT FROM AUTHOR]

l‐(+)‐Muscarin (1)‐produzierende Pilze stellen eine ernste Gefahr für die menschliche Gesundheit dar, da deren Aufnahme zu Kreislaufversagen oder sogar zum Tod führen kann. Jedoch ist deren Inhaltsstoff‐Profil erstaunlich wenig verstanden, ebenso fehlt Wissen zur Freisetzung dieses Giftes und zu potentiell giftigen verwandten Stoffen. Wir identifizierten im Mycel des 1‐produzierenden Rinnigbereiften Trichterlings Clitocybe rivulosa 4'‐Phosphomuscarin (2) als hauptsächlichen Inhaltsstoff. Dessen Struktur wurde durch hochauflösende Massenspektrometrie, Kernresonanzspektroskopie, und durch Vergleich mit einem synthetisierten Standard aufgeklärt. Diese bislang übersehene phosphorylierte Verbindung detektierten wir ebenfalls in den Risspilzen Pseudosperma spectrale und Inocybe nitidiuscula. Studien zur Aktivierung des muscarinischen Acetylcholinrezeptors M3 zeigten nur geringe Affinität von 2 am Wirkort. Außerdem präsentieren wir biologische Beweise, dass Muscaridin (3), ein mit 1 verwandtes und mit diesem zusammen vorkommendes quaternäres Amin den muscarinischen Acetylcholinrezeptor M3 menschlicher embryonaler Nierenzellen nicht aktiviert. Unsere Arbeit gewährt wichtige Einblicke in das Inhaltsstoffprofil und die Pharmakologie einiger der wichtigsten Giftpilze. Da das harmlose 2 durch unspezifische enzymatische Esterspaltung das potentiell tödliche 1 freisetzen kann, sind diese Ergebnisse für die Notfallmedizin sehr relevant, um die wahre Toxizität dieser Pilze einzuschätzen. [ABSTRACT FROM AUTHOR]

l‐(+)‐Muscarine (1)‐producing mushrooms pose a severe threat to human health as ingestion can result in circulatory collapse or even death. However, their metabolic profile is surprisingly poorly understood, including knowledge of poison release and potentially toxic congeners. In the mycelium of the 1‐producing fool's funnel mushroom Clitocybe rivulosa, we identified 4'‐phosphomuscarine (2) as the major natural product. Its structure was elucidated by high‐resolution mass spectrometry, nuclear magnetic resonance spectroscopy and by comparison with a synthesized reference. We also detected this previously overlooked phosphorylated compound in the fiber cap mushrooms Pseudosperma spectrale and Inocybe nitidiuscula. Studies on the activation of the muscarinic acetylcholine receptor M3 indicate only weak affinity of 2 to this target. Furthermore, we present biological evidence that muscaridine (3), a quaternary amine congener related to and co‐occurring with 1, does not activate the muscarinic acetylcholine receptor M3 on human embryonic kidney cells. Our work provides important insight into the metabolic profile and the pharmacology of some of the most poisonous mushrooms. As the harmless 2 can liberate the potentially fatal 1 by unspecific enzymatic ester cleavage, these results are highly relevant for emergency medicine to estimate the true toxicity of these mushrooms. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive model of predator–prey interactions within a toxic environment, with a particular focus on the effect of toxicant compounds on the development of populations. By incorporating environmental disturbances, the dynamics of the model are investigated to enhance the system’s authenticity. Analytical explanations have been provided for the deterministic system solutions, including positivity, uniform boundedness and persistence. The deterministic portion of the investigation entails a comprehensive examination of occurrence and stability criteria pertaining to every possible equlibria. The bifurcation studies conducted on the system exhibit the appearance of local bifurcations, including transcritical, saddle-node and Hopf bifurcations. Moreover, these evaluations establish the parametric region in which Bautin, Bogdanov–Takens and cusp bifurcation occur. Under a relevant selection of parametric values, the suggested system has the capacity to manifest a wide range of dynamic phenomena, such as bi-stable behavior, emergence of limit cycles, and presence of homoclinic loops. Furthermore, in a stochastic environment, the use of Lyapunov functions explains the existence of a global positive solution. It has additionally been argued that the proposed system exhibits ultimate stochastic boundedness. Subsequently, specific and adequate criteria demonstrate the eradication of both species as well as the long-term survival of prey communities. We have also investigated the impact of the exogenous input rate of toxic substances and the coefficient of toxic substances in both species on the behavior of the whole system, both in deterministic and stochastic scenarios. Theoretical findings have been confirmed by various numerical investigations. [ABSTRACT FROM AUTHOR]

Bacteria use the type VI secretion system (T6SS) to secrete toxins into pro- and eukaryotic cells via machinery consisting of a contractile sheath and a rigid tube. Rearrangement hotspot (Rhs) proteins represent one of the most common T6SS effectors. The Rhs C-terminal toxin domain displays great functional diversity, while the Rhs core is characterized by YD repeats. We elucidate the Rhs core structures of PAAR- and VgrG-linked Rhs proteins from Salmonella bongori and Advenella mimigardefordensis , respectively. The Rhs core forms a large shell of β-sheets with a negatively charged interior and encloses a large volume. The S. bongori Rhs toxin does not lead to ordered density in the Rhs shell, suggesting the toxin is unfolded. Together with bioinformatics analysis showing that Rhs toxins predominantly act intracellularly, this suggests that the Rhs core functions two-fold, as a safety feature for the producer cell and as delivery mechanism for the toxin. [Display omitted] • PAAR- and VgrG-linked Rhs form large, negatively charged shells • Rhs toxins function predominantly intracellularly, in contrast to non-Rhs toxins • TMDs, prePAAR motifs, and VIRs are not consistently present in Rhs effectors Kielkopf et al. elucidate the structures of two bacterial T6SS-associated Rhs proteins. Rhs cores form large, negatively charged shells that encapsulate unfolded or molten globule toxin domains. Their bioinformatic analyses show that Rhs toxins predominantly act intracellularly and that TMDs, prePAAR motifs, and VIRs are not consistently present in Rhs effectors. [ABSTRACT FROM AUTHOR]

Purpose of Review: Snakebite envenomation, classified as a neglected tropical disease, represents a significant global health threat, particularly in Asia and Africa, where it causes between 57,000 and 100,000 deaths annually. Envenomation by cobras, especially those of the genus Naja, contributes substantially to this burden. This review explores the complexities of cobra venom composition, its associated complications, and current treatment strategies, with a focus on venom-derived therapeutic prospects. Recent Findings: Cobra venom is a complex mixture primarily composed of proteins and peptides that exert various toxic effects, including neurotoxicity, tissue damage, and systemic complications. Antivenom therapy remains the primary treatment for envenomation, successfully mitigating critical effects such as bleeding and paralysis. Recent research, however, has revealed that certain venom-derived molecules possess therapeutic potential, opening up new possibilities for drug development. Summary: Despite the lethal nature of cobra envenomation, advances in antivenom therapy and emerging research into the medicinal properties of venom-derived molecules offer hope. This review highlights the dual nature of cobra venom—both as a source of severe pathology and as a potential reservoir for therapeutic agents—fostering the development of novel drugs. [ABSTRACT FROM AUTHOR]

Background: Extracorporeal membrane oxygenation (ECMO) is used in Hong Kong to provide additional circulation and respiratory support to patients. Exposure to toxins could cause profound shock and respiratory failure. The role of using ECMO to support severe circulatory and respiratory failure in patients with a toxicological cause of admission in Hong Kong is explored in this study. Objective: This study aims to describe the local practice of the use of ECMO in poisoning in Hong Kong. Method: This was a retrospective analysis of patients receiving ECMO for toxicological‐related causes between January 2013 and December 2023. Indications, the poisons of concern, and the mortality of the patients were reviewed. Results: We reported a total of 20 cases during the study period. Fourteen of them received VA‐ECMO, and six of them received VV‐ECMO. The most common poisons in patients receiving VA‐ECMO were calcium channel blockers and beta blockers. The ICU mortality rate for patients receiving VV‐ECMO was 16.6%, whereas it was 42.8% for those receiving VA‐ECMO. Of the 4 patients who received ECPR, the mortality rate was 75%. Most of the patients who survived had excellent cerebral performance category at 3 months. Conclusion: ECMO might be a useful modality for providing temporary respiratory and circulatory support to poisoned patients. [ABSTRACT FROM AUTHOR]

Mycolactone is a complex macrolide toxin produced by Mycobacterium ulcerans, the causative agent of Buruli ulcer. The aim of this paper is to review the chemistry, biosynthetic, and synthetic pathways of mycolactone A/B to help develop an understanding of the mode of action of these polyketides as well as their therapeutic potential. The synthetic work has largely been driven by the desire to afford researchers enough (≥100 mg) of the pure toxins for systematic biological studies toward understanding their very high biological activities. The review focuses on pioneering studies of Kishi which elaborate first-, second-, and third-generation approaches to the synthesis of mycolactones A/B. The three generations focused on the construction of the key intermediates required for the mycolactone synthesis. Synthesis of the first generation involves assignment of the relative and absolute stereochemistry of the mycolactones A and B. This was accomplished by employing a linear series of 17 chemical steps (1.3% overall yield) using the mycolactone core. The second generation significantly improved the first generation in three ways: (1) by optimizing the selection of protecting groups; (2) by removing needless protecting group adjustments; and (3) by enhancing the stereoselectivity and overall synthetic efficiency. Though the synthetic route to the mycolactone core was longer than the first generation, the overall yield was significantly higher (8.8%). The third-generation total synthesis was specifically aimed at an efficient, scalable, stereoselective, and shorter synthesis of mycolactone. The synthesis of the mycolactone core was achieved in 14 linear chemical steps with 19% overall yield. Furthermore, a modular synthetic approach where diverse analogues of mycolactone A/B were synthesized via a cascade of catalytic and/or asymmetric reactions as well as several Pd-catalyzed key steps coupled with hydroboration reactions were reviewed. In addition, the review discusses how mycolactone is employed in the diagnosis of Buruli ulcer with emphasis on detection methods of mass spectrometry, immunological assays, RNA aptamer techniques, and fluorescent-thin layer chromatography (f-TLC) methods as diagnostic tools. We examined studies of the structure–activity relationship (SAR) of various analogues of mycolactone. The paper highlights the multiple biological consequences associated with mycolactone such as skin ulceration, host immunomodulation, and analgesia. These effects are attributed to various proposed mechanisms of actions including Wiskott–Aldrich Syndrome protein (WASP)/neural Wiskott–Aldrich Syndrome protein (N-WASP) inhibition, Sec61 translocon inhibition, angiotensin II type 2 receptor (AT2R) inhibition, and inhibition of mTOR. The possible application of novel mycolactone analogues produced based on SAR investigations as therapeutic agents for the treatment of inflammatory disorders and inflammatory pain are discussed. Additionally, their therapeutic potential as anti-viral and anti-cancer agents have also been addressed. [ABSTRACT FROM AUTHOR]

BACKGROUND: Widespread resistance of insect pests to insecticides and transgenic crops in the field is a significant challenge for sustainable agriculture, and calls for the development of novel alternative strategies to control insect pests. One potential resource for the discovery of novel insecticidal molecules is natural toxins, particularly those derived from the venoms of insect predators. RESULTS: In this study, we identified three insecticidal proteinaceous toxins from the venom glands (VGs) of the predatory stink bug, Arma custos (Hemiptera: Asopinae). Transcriptomic analysis of A. custos VGs revealed 151 potentially secreted VG‐rich venom proteins. Three VG‐rich venom proteins (designated AcVP1 ~ 3) were produced by overexpression in Escherichia coli. Injection of the recombinant proteins into tobacco cutworm (Spodoptera litura) larvae showed that all of the three recombinant proteins caused paralysis, liquefaction and death. Injection of recombinant proteins into rice brown planthopper (Nilaparvata lugens) nymphs showed higher insecticidal activities, among which a trypsin (AcVP2) caused 100% mortality postinjection at 1.27 pmol mg−1 body weight. CONCLUSION: A natural toolkit for the discovery of insecticidal toxins from predatory insects has been revealed by the present study. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

SUMMARY: Animal feed hygiene is a critical aspect of ensuring the safety and well-being of animals and the quality of animal products. Contamination of animal feed can lead to various hazards and diseases, affecting both animal diseases and human food safety. Observance of poultry feed hygiene in feed mill factories should be one of the most important issues to witness a reduction in cost and increase in production. Food/feed safety veterinarian should be to control of hygiene of human/animal commodity to safety and public health. Microbial hazards are major agent which seen in food/feed and secondary metabolites of fungal is named of mycotoxin are highly toxic metabolits compounds that produced in ingredient and finish feedstuffs. The effects of mycotoxin on poultry include reduced feed intake, growth performance, immunity, antioxidants status and blood parameters, and they have been associated with increased mortality, carcinogenicity, teratogenicity and organ damage in poultry industry. Poultry feed hygiene regulations are crucial for ensuring the safety and quality of animal feed products. The aim of this study was to prevent the contamination of poultry feed with harmful substances are control of its negative impact on poultry health and human food safety. This review provides an overview of feed health factors with the importance of mycotoxins and poultry feed contamination by natural toxins. Contamination of raw materials with mycotoxins in poultry feedstuffs during production is a significant challenge for the safety and quality of finish poultry feed. The importance of monitoring and controlling mycotoxin contamination in poultry feedstuffs to ensure poultry/human health. [ABSTRACT FROM AUTHOR]

Aspergillus flavus and aflatoxin on pistachio are the most important hazards to human health, which start in the orchard and will continue to the storage. This research selected 16 most effective yeast strains through dual culture (DC) assay according to the interaction between 376 yeast strains and A. flavus isolate P1684 in an initial screening. The antifungal ability of the strains was determined to be 94.5%, 72.08 %, and 91.31% in DC, volatile organic compounds (VOCs), and extracellular secretions (ESs) assays, respectively. In DC and VOCs assays, the YE 43-6 yeast strain showed maximum inhibition of growth, whereas powder and liquid formulation of the YE 43-10 yeast strain showed better performance. Ammonia vapor assay revealed that yeast strains significantly reduced aflatoxin production in A. flavus. Under in-situ conditions, trees were sprayed with cell/spore populations of both effective yeasts and A. flavus to determine the ability of yeast strains to compete with the pathogen. After 45 days, the fruits were harvested, and the average number of colonies per pistachio fruit unit (CFU/Nut) was determined. The highest and lowest reduction of populations were observed in YE 43-10 (85.71%) and YE 36-9 (35.18%), respectively. In both YE 43-6 and YE 43-10 strains, powder formulation was slightly more effective than liquid, and VOCs effectively prevented pistachio contamination with A. flavus and aflatoxin.

Abstract Background Clostridioides difficile has been recognized as an emerging pathogen in both humans and animals. In this context, antimicrobial resistance plays a major role in driving the spread of this disease, often leading to therapeutic failure. Moreover, recent increases in community-acquired C. difficile infections have led to greater numbers of investigations into the animal origin of the disease. The aim of this study was to evaluate the genetic similarities between 23 environmental and animal isolates by using whole-genome sequencing and to determine antimicrobial resistance and virulence factor genes in toxigenic C. difficile strains to provide important data for the development of diagnostic methods or treatment guidelines. Results The most common sequence type was ST11 (87%), followed by ST2 (9%) and ST19 (4%). In addition, 86.95% of the strains exhibited multidrug resistance, with antimicrobial resistance to mainly aminoglycosides, fluoroquinolones, tetracycline and B-lactams; nevertheless, one strain also carried other resistance genes that conferred resistance to lincosamide, macrolides, streptogramin a, streptogramin b, pleuromutilin, oxazolidinone and amphenicol. In addition, a wide range of virulence factor genes, such as those encoding adherence factors, exoenzymes and toxins, were found. However, we observed variations between toxinotypes, ribotypes and sequence types. Conclusions The results of this study demonstrated significant genetic similarity between ST11 strains isolated from environmental sampling and from animal origin; these strains may represent a reservoir for community-acquired C. difficile infection, which is becoming a growing public health threat due to the development of multridug resistant (MDR) bacteria and the number of virulence factors detected.

La connaissance de l'anatomie permet non seulement un traitement optimum et donc une satisfaction pleine et entière de nos patientes, mais est aussi fondamentale dans la prévention des complications. Une compréhension approfondie du vieillissement permet de réaliser des traitements efficaces, car la plupart des patientes réclament un résultat naturel, supprimant les signes inévitables de l'âge, qui ne peuvent être compris qu'en prenant en compte leur vieillissement. Le vieillissement du visage est un processus naturel, mais multifactoriel complexe, plus particulièrement pour le front. Dans cet article, nous nous concentrerons sur la toxine botulique ainsi que les produits de comblement dans le cadre du vieillissement. Knowledge of anatomy not only allows optimal treatment and therefore full satisfaction of our patients, but is also fundamental in the prevention of complications. A thorough understanding of aging allows for effective treatments, as most patients demand a natural result, removing the inevitable signs of aging, which can only be understood by considering their aging. Facial aging is a natural but complex multifactorial process, particularly for the forehead. In this article, we will focus on botulinum toxin as well as fillers in aging. [ABSTRACT FROM AUTHOR]

The development of sustainable food preservation techniques and technologies to mitigate food losses and wastage during the harvest season has become a trending topic of global interest. This paper concisely summarizes the modern trends in food preservation as an indispensable element in the emerging food industry. The need to ensure the integrity of food preserved over a prolonged period is imperative to ascertain the quality of food consumed by humans. The food industry has recently been inundated with innovative techniques for better efficiency of food preservation technique that sustains the nutritive value and dietary content. Since the most widely adopted techniques include chemical, biological and physical methods, emphasis has been placed on this discussion in this review. While a series of other conventional and non-conventional techniques of preservation has been developed to achieve a longer shelf life of food, chemical preservation techniques seem to be more widely adopted essentially due to their ease of use, affordability and tendency to maintain the nutritional quality of food products for a prolong period. Despite the disadvantage of toxin introduction by chemicals among other associated hazards, chemical preservative techniques enjoy superior patronage. The presence of moisture in food, allowing microbes to thrive and their elimination via thermal means, is often a great choice. Chemical preservation receives more attention because of the impossibility of eliminating moisture via thermal means in many cases. Modern, advanced, innovative food preservative techniques such as the use of high-pressure processing, thermal processing, microwave, ultraviolet, infrared, ionizing, biosensors, vacuum packaging, high electric discharge, high hydrostatic processing, magnetic field, pulsed electric field, ultrasonication, nanotechnology means need further investigation and adaptation for seamless application. [ABSTRACT FROM AUTHOR]

Clostridioides difficile strains of sequence type (ST) 37, primarily including PCR ribotype (RT) 017, are prevalent in mainland China. Our study aimed to compare the major virulence factors of an epidemic C. difficile isolate of ST37 type (Xy06) from China with the well-characterized C. difficile reference strains R20291 (RT027) and CD630E (ST54), as well as a Chinese ST54 strain (Xy07) isolated from the same hospital. The Xy06 genome was predicted to harbor two complete prophages and several transposon-like elements. Comparative analysis of PaLoc revealed a truncated tcdA gene, a functional tcdB gene, a functional tcdC gene, and well-conserved tcdR and tcdE genes. Phenotypic comparisons showed that Xy06 was a robust producer of TcdB, readily sporulated and germinated, and strongly bound to human gut epithelial cells. In a mouse model of C. difficile infection, Xy06 was more virulent than strains CD630E and Xy07 and was comparable to strain R20291 in virulence. Our data suggest the potential threat of the epidemic ST37 strains in China. [ABSTRACT FROM AUTHOR]

Background/Aim: Pasteurella multocida is a significant cause of morbidity and mortality in rabbits, as well as other species. Some isolates elaborate a heat-labile toxin (PMT) that has been shown to be an important virulence factor. Though previous studies have demonstrated protective immunity can be conferred via immunization of rabbits with heat-inactivated PMT (IPMT), we investigated the ability of immunization to impact colonization of P. multocida. Materials and Methods: Rabbits were immunized at days 0, 7 and 14 with either phosphate buffered saline (PBS), the mucosal adjuvant cholera toxin (CT), IMPT or IPMT + CT. Male New Zealand white rabbits were used and confirmed to be free of P. multocida prior to experimentation. Results: Serum IgG and nasal lavage fluid IgA responses directed against PMT were found in rabbits immunized with IPMT, with or without CT, but not in those immunized with only PBS or CT; and the addition of CT to IPMT enhanced the response. Significantly more P. multocida CFUs (p≤0.05) were cultured from the lungs of rabbits immunized with IPMT, with or without CT, compared to those administered only PBS or CT, although no differences were observed in nasal lavage fluid samples. Further, immunization IPMT, with or without CT, conferred protection against pleuritis and pneumonia. Conclusion: PMT, in addition to its role as a virulence factor, may serve as a colonization factor for P. multocida in the lungs of rabbits. [ABSTRACT FROM AUTHOR]

Shouchella clausii (S. clausii) has been marketed as an important commercial probiotic, displaying significant therapeutic effects on antibiotic-associated diarrhea and providing benefits to humans. This study aimed to explore the distribution, adaptation, and probiotic properties of S. clausii. Based on 16S rRNA gene analysis, 43 strains of S. clausii were isolated from 317 soil samples in China. Based on the genomic index of Average Nucleotide Identity (ANI) results, 41 strains were confirmed as S. clausii, while two strains, FJAT-45399 and FJAT-45335, were identified as potential novel species distinct from S. clausii. Combined phenotypic and genomic predictions indicated that S. clausii could survive under harsh conditions. Comparative genomics revealed that these isolates possess antibiotic resistance genes, as well as capabilities for bacteriocin and folate production, while lacking toxins and hemolytic activity. Hemolysis tests indicated that strain FJAT-41761 exhibited non-pathogenic γ-hemolytic activity, while also demonstrating resistance to multiple antibiotics, consistent with probiotic characteristics. These findings suggest that strain FJAT-41761 is safe and holds potential as a future probiotic. [ABSTRACT FROM AUTHOR]

Pathogenic serotypes of Vibrio cholerae, transmitted through contaminated water and food, are responsible for outbreaks of cholera, an acute diarrheal disease. While the cholera toxin is the primary virulence factor, V. cholerae also expresses other virulence factors, such as the tripartite toxin MakABE that is secreted via the bacterial flagellum. These three proteins are co-expressed with two accessory proteins, MakC and MakD, whose functions remain unknown. Here, we present the crystal structures of MakC and MakD, revealing that they are similar in both sequence and structure but lack other close structural relatives. Our study further investigates the roles of MakC and MakD, focusing on their impact on the expression and secretion of the components of the MakABE tripartite toxin. Through deletion mutant analysis, we found that individual deletions of makC or makD do not significantly affect MakA expression or secretion. However, the deletion of both makC and makD impairs the expression of MakB, which is directly downstream, and decreases the expression of MakE, which is separated from makCD by two genes. Conversely, MakA, encoded by the makA gene located between makB and makE, is expressed normally but its secretion is impaired. Additionally, our findings indicate that MakC, in contrast to MakD, exhibits strong interactions with other proteins. Furthermore, both MakC and MakD were observed to be localized within the cytosol of the bacterial cell. This study provides new insights into the regulatory mechanisms affecting the Mak protein family in V. cholerae and highlights the complex interplay between gene proximity and protein expression. [ABSTRACT FROM AUTHOR]

Background: Clostridioides difficile has been recognized as an emerging pathogen in both humans and animals. In this context, antimicrobial resistance plays a major role in driving the spread of this disease, often leading to therapeutic failure. Moreover, recent increases in community-acquired C. difficile infections have led to greater numbers of investigations into the animal origin of the disease. The aim of this study was to evaluate the genetic similarities between 23 environmental and animal isolates by using whole-genome sequencing and to determine antimicrobial resistance and virulence factor genes in toxigenic C. difficile strains to provide important data for the development of diagnostic methods or treatment guidelines. Results: The most common sequence type was ST11 (87%), followed by ST2 (9%) and ST19 (4%). In addition, 86.95% of the strains exhibited multidrug resistance, with antimicrobial resistance to mainly aminoglycosides, fluoroquinolones, tetracycline and B-lactams; nevertheless, one strain also carried other resistance genes that conferred resistance to lincosamide, macrolides, streptogramin a, streptogramin b, pleuromutilin, oxazolidinone and amphenicol. In addition, a wide range of virulence factor genes, such as those encoding adherence factors, exoenzymes and toxins, were found. However, we observed variations between toxinotypes, ribotypes and sequence types. Conclusions: The results of this study demonstrated significant genetic similarity between ST11 strains isolated from environmental sampling and from animal origin; these strains may represent a reservoir for community-acquired C. difficile infection, which is becoming a growing public health threat due to the development of multridug resistant (MDR) bacteria and the number of virulence factors detected. [ABSTRACT FROM AUTHOR]

In food safety analysis, the detection and control of foodborne pathogens and their toxins are of great importance. Monitoring of virus transmission is equally important, especially in light of recent findings that coronaviruses have been detected in frozen foods and packages during the current global epidemic of coronavirus disease 2019. In recent years, field-effect transistor (FET) biosensors have attracted considerable scholarly attention for pathogenic microorganisms and toxins detection and sensing due to their rapid response time, high sensitivity, wide dynamic range, high specificity, label-free detection, portability, and cost-effectiveness. FET-based biosensors can be modified with specific recognition elements, thus providing real-time qualitative and semiquantitative analysis. Furthermore, with advances in nanotechnology and device design, various high-performance nanomaterials are gradually applied in the detection of FET-based biosensors. In this article, we review specific detection in different biological recognition elements are immobilized on FET biosensors for the detection of pathogenic microorganisms and toxins, and we also discuss nonspecific detection by FET biosensors. In addition, there are still unresolved challenges in the development and application of FET biosensors for achieving efficient, multiplexed, in situ detection of pathogenic microorganisms and toxins. Therefore, directions for future FET biosensor research and applications are discussed. [ABSTRACT FROM AUTHOR]

An isolate of a Gram-positive, strictly aerobic, motile, rod-shaped, endospore forming bacterium was originally isolated from soil when screening and bioprospecting for plant beneficial microorganisms. Phylogenetic analysis of the 16S rRNA gene sequences indicated that this strain was closely related to Lysinibacillus fusiformis NRRL NRS-350T (99.7%) and Lysinibacillus sphaericus NRRL B-23268T (99.2%). In phenotypic characterization, the novel strain was found to grow between 10 and 45 °C and tolerate up to 8% (w/v) NaCl. Furthermore, the strain grew in media with pH 5 to 10 (optimal growth at pH 7.0). The predominant cellular fatty acids were observed to be iso-C15: 0 (52.3%), anteiso-C15: 0 (14.8%), C16:1ω7C alcohol (11.2%), and C16: 0 (9.5%). The cell-wall peptidoglycan contained lysine-aspartic acid, the same as congeners. A draft genome was assembled and the DNA G+C content was determined to be 37.1% (mol content). A phylogenomic analysis on the core genome of the new strain and 5 closest type strains of Lysinibacillus revealed this strain formed a distinct monophyletic clade with the nearest neighbor being Lysinibacillus fusiformis. DNA–DNA relatedness studies using in silico DNA–DNA hybridizations (DDH) showed this species was below the species threshold of 70%. Based upon the consensus of phylogenetic and phenotypic analyses, we conclude that this strain represents a novel species within the genus Lysinibacillus, for which the name Lysinibacillus pinottii sp. nov. is proposed, with type strain PB211T (= NRRL B-65672T, = CCUG 77181T). [ABSTRACT FROM AUTHOR]

In this paper we explores a mathematical model with toxin producing spaces and viral infection of plankton bloom in a nutrient phytoplankton. Here we discuss the simple law of mass action and Holling type-II function for response term. We also discuss the equilibria and their existence and local stability of equilibrium points. To investigate the biological significance of threshold parameters. In this paper we observed that stable, coexistence and periodic oscillatory and periodic solution. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was the analysis of the problem of laryngeal dystonia in patients of Otolaryngology and Neurology Clinics to assess the efficiency of effects of Botulin Toxin type A (BOTOXTM) injections on voice quality and function of vocal cords with the use of videolaryngostroboscopic and laryngographic examinations, GRBAS (G - grade of hoarseness, R - roughness, B - breathiness, A - aesthenia, S -strain) scale and voice field. Material and methods: Between 2020 and 2022 a total of 50 patients with laryngeal dystonia were examined. The videolaryngostroboscopic and laryngographic examinations confirmed laryngeal dystonia. Afterwards the patients undertook Botulinum Toxin type A injections into the thyro-arythenoid muscle. Results: Control examinations confirmed the improvement of vocal folds movability and the decrease in number of irregular vocal folds vibrations. The next injection of BOTOXTM substance was done 3-6 months after the last injection. Conclusions: The results of our study suggest that although BOTOXTM toxin still remains the main form of treatment for laryngeal dystonia, using it improves phonatory function of larynx (as proven by videolaryngostroboscopic examination). [ABSTRACT FROM AUTHOR]

Toxin–antitoxin (TA) systems in bacteria are key regulators of the cell cycle and can activate a death response under stress conditions. Like other bacterial elements, TA modules have been widely exploited for biotechnological purposes in diverse applications, such as molecular cloning and anti-cancer therapies. However, their use in plants has been limited, leaving room for the development of new approaches. In this study, we examined two TA systems previously tested in plants, MazEF and YefM-YoeB, and identified interesting differences between them, likely related to their modes of action. We engineered modifications to these specific modules to transform them into molecular switches that can be activated by a protease, inducing necrosis in the plant cells where they are expressed. Finally, we demonstrated the antiviral potential of the modified TA modules by using, as a proof-of-concept, the potyvirus plum pox virus as an activator of the death phenotype. [ABSTRACT FROM AUTHOR]

The pine processionary moth Thaumetopoea wilkinsoni (Tams, 1926) (Lepidoptera: Notodontidae) is one of the most harmful species that causes destruction in pine ecosystems and also causes critical skin reactions in humans and animals due to its urticating hairs. This study aimed to evaluate the efficacy of different strains [Bti ATCC 35646 (wild-type strain), Bti pHT315, and Bti pHTppk (mutant strain)] of Diptera-targeted Bacillus thuringiensis subsp. israelensis (Bti) and toxins (spore/crystal mixtures) obtained from these strains against the 4th larval stage of T. wilkinsoni under laboratory conditions. T. wilkinsoni eggs were collected from pine trees at Ondokuz Mayıs University in Samsun, Turkey, in 2022. Pine needles were contaminated with bacterial strains of different concentrations (1 × 107, 1 × 108, 1 × 109 cfu/mL) in 5 mL and toxins in different concentrations (0.15, 0.3, 0.6, 1.25, 2.5, 5 mg/mL) in 2 mL. Larvae were placed in containers with 30 larvae in each group and were observed for 25 days. As a result of the study, Bti ATCC 35646 with 63.4% mortality and the lowest LC50 value of 1.2 × 109 cfu/mL among the three strains of Bti and Bti pHTppk with 76.7% mortality and the lowest LC50 value of 1.2 mL among the toxins from the Bti strains had found to be virulent for T. wilkinsoni. The results obtained from our study suggest that Diptera-targeted Bti is virulent to T. wilkinsoni and that this strain and spore/crystal mixture can be used in the biological control of this species. [ABSTRACT FROM AUTHOR]

Escherichia coli strains producing the genotoxin colibactin, designated as CoPEC (colibactin-producing E. coli), have emerged as an important player in the etiology of colorectal cancer (CRC). Here, we investigated the role of macroautophagy/autophagy in myeloid cells, an important component of the tumor microenvironment, in the tumorigenesis of a susceptible mouse model infected with CoPEC. For that, a preclinical mouse model of CRC, the ApcMin/+ mice, with Atg16l1 deficiency specifically in myeloid cells (ApcMin/+/Atg16l1[∆MC]) and the corresponding control mice (ApcMin/+), were infected with a clinical CoPEC strain 11G5 or its isogenic mutant 11G5∆clbQ that does not produce colibactin. We showed that myeloid cell-specific Atg16l1 deficiency led to an increase in the volume of colonic tumors in ApcMin/+ mice under infection with 11G5, but not with 11G5∆clbQ. This was accompanied by increased colonocyte proliferation, enhanced inflammasome activation and IL1B/IL-1β secretion, increased neutrophil number and decreased total T cell and cytotoxic CD8+ T cell numbers in the colonic mucosa and tumors. In bone marrow-derived macrophages (BMDMs), compared to uninfected and 11G5∆clbQ-infected conditions, 11G5 infection increased inflammasome activation and IL1B secretion, and this was further enhanced by autophagy deficiency. These data indicate that ATG16L1 in myeloid cells was necessary to inhibit colonic tumor growth in CoPEC-infected ApcMin/+ mice via inhibiting colibactin-induced inflammasome activation and modulating immune cell response in the tumor microenvironment. Abbreviation: AOM, azoxymethane; APC, APC regulator of WNT signaling pathway; ATG, autophagy related; Atg16l1[∆MC] mice, mice deficient for Atg16l1 specifically in myeloid cells; CASP1, caspase 1; BMDM, bone marrow-derived macrophage; CFU, colony-forming unit; CoPEC, colibactin-producing Escherichia coli; CRC, colorectal cancer; CXCL1/KC, C-X-C motif chemokine ligand 1; ELISA, enzyme-linked immunosorbent assay; IL, interleukin; MC, myeloid cell; MOI, multiplicity of infection; PBS, phosphate-buffered saline; pks, polyketide synthase; qRT-PCR, quantitative real-time reverse-transcription polymerase chain reaction; siRNA, small interfering RNA; TME, tumor microenvironment; TNF/TNF-α, tumor necrosis factor. [ABSTRACT FROM AUTHOR]

Acute intoxications and poisonings are a relevant cause for ICU admission of critically ill patients. This study aimed to determine the characteristics of intoxicated patients in a tertiary center medical ICU in Austria over time and to investigate parameters associated with ICU mortality. This study was a retrospective data analysis including adult ICU patients from the years 2007 to 2021. In addition to ICU documentation, pre-hospital, and emergency department documents as well as autopsy reports were utilized. In an exploratory subanalysis, we compared these findings to a historical dataset from our facility from 1992 to 1996. We identified 581 cases admitted to the medical ICU because of acute poisoning (2007–2021), of which 45% were female and 46.6% were mixed intoxications. Suicidal intent was the primary cause of intoxication (48.2%) and ICU length of stay was median 1.2 days. The majority of deceased patients received pre-hospital mechanical CPR. Primary and secondary poison/toxin removal modalities were used in 29.9% and 11.7% of cases, whereas antidotes were administered in 54.4%. Comparing the data with a historical cohort (n = 168), we found a shift in primary detoxification away from gastric lavage and an increase in alternative secondary poison/toxin removal techniques. The ICU mortality was 4.1% and 4.2% in the present and historic cohort, respectively. Pre-existing psychiatric illnesses increased from 49% in the historic to 69% in the present cohort. Psychiatric illness predisposes patients to severe intoxications necessitating ICU care, thus increasing prevention measures seems warranted. Females did present with a different spectrum of intoxications compared to males. ICU mortality remained low over time and most deceased patients had a grim prognosis already on ICU arrival. [ABSTRACT FROM AUTHOR]

Ricin is a toxic protein regarded as a potential chemical weapon for bioterrorism or criminal use. In the event of a ricin incident, rapid analytical methods are essential for ricin confirmation in a diversity of matrices, from environmental to human or food samples. Mass spectrometry–based methods provide specific toxin identification but require prior enrichment by antibodies to reach trace-level detection in matrices. Here, we describe a novel assay using the glycoprotein asialofetuin as an alternative to antibodies for ricin enrichment, combined with the specific detection of signature peptides by high-resolution mass spectrometry. Additionally, optimizations made to the assay reduced the sample preparation time from 5 h to 80 min only. Method evaluation confirmed the detection of ricin at trace levels over a wide range of pH and in protein-rich samples, illustrating challenging matrices. This new method constitutes a relevant antibody-free solution for the fast and specific mass spectrometry detection of ricin in the situation of a suspected toxin incident, complementary to active ricin determination by adenine release assays. [ABSTRACT FROM AUTHOR]

Mushrooms produce a great variety of defense chemical compounds to protect themselves from fungivores. Alpha‐amanitin is one of such compounds found in some Amanita mushrooms. The present study focuses on the effect of α‐amanitin on adult survival in 17 drosophilid species including mycophagous ones from the subgenus Drosophila and the genus Hirtodrosophila and nonmycophagous ones of the subgenera Drosophila, Siphlodora and Sophophora. The results showed that all the essential fungivores and some partially mycophagous species from different lineages are tolerant to this lethal toxin at a concentration of 50 μg/mL, suggesting that the α‐amanitin tolerance may have been acquired more or less independently of the evolution of mycophagy in the family Drosophilidae. [ABSTRACT FROM AUTHOR]

Bisphenol-A (BPA) is a synthetically manufactured phenolic substance that is very widely employed in producing polycarbonate polymers and epoxy resins which further can be found in numerous items of daily use such as foodstuff and their containers, beverages, milk, audit rolls, dental fillings and so forth. Additionally, it is present in the air we breathe-in. The studies have reported that BPA produces toxic impacts on reproductive, cardiovascular, endocrine, renal, gastrointestinal, immune, respiratory, nervous and skeletal system. In the current literature review, we have targeted to highlight the protective role of herbs in opposition to BPA toxicity. The gift of nature-'Plants' seem to be very efficient and potential agents to overcome the BPA induced toxicity as they themselves are devoid of adverse effects. Plants contain a mixture of phyto-molecules which together act to provide a synergistic effect. Further, we have explained the signaling mechanisms implicated in BPA toxicity. Even though, multiple mechanisms involved in BPA toxicity have been examined, no particular target therapy for this toxicity is available at present. Thus, naturally occurring substances may be looked at in the future for restorative use to mitigate the deleterious and negative consequences of exposure to BPA. [ABSTRACT FROM AUTHOR]

ABSTRACT Widespread vagal activation following honey consumption is a sign of mad honey poisoning. Early initiation and appropriate treatment can prevent fatal outcomes.

Background: The seeds of Abrus precatorius are highly poisonous with no antidote available and are often consumed as a means of suicide. To date, there are no clear treatment strategies for Abrus poisoning induced by ingestion. Case report: Here, we report a case in which a large number of Abrus precatorius seeds was successfully removed using gastrointestinal surgery to rescue the patient.Why should an emergency physician be aware of this?Abrus precatorius, as a rare but important cause of plant poisoning, is usually being unrecognized even by emergency physicians in China because of its scarce documentation in the Chinese medical literature. In managing such instances of intoxication, conventional gastric emptying techniques prove insufficient to effectively address the toxicity. Through this report, we hope to raise public awareness regarding this highly toxic plant. We also aim to offer a treatment reference for clinicians encountering similar situations.

The foodborne mycotoxin deoxynivalenol (DON) produced by Fusarium species threats animal and human health through disruption of the intestinal barrier. Targeting the gut microbiota and its products appears as a promising strategy to mitigate DON intestinal toxicity. In this study, we investigated whether the bacterial metabolite butyrate could alleviate epithelial barrier disruption induced by DON. We used a model of cell monolayers derived from porcine jejunum organoids allowing to reproduce the cellular complexity of the intestinal epithelium. Our results show that DON dose-dependently disrupted the epithelial barrier integrity, reduced epithelial differentiation, and altered innate immune defenses. Butyrate attenuated the DON-induced increase in paracellular permeability. Butyrate also prevented epithelial barrier dysfunction triggered by anisomycin, a ribosome inhibitor like DON. Moreover, butyrate partially counteracted the effects of DON on tight junctions (TJP1, OCLN), innate epithelial defenses (PTGS2, CD14, TLR4, TLR5), and absorptive cell functions (CA2, VIL1, NHE3, CFTR). In contrast, butyrate did not prevent the toxic effects of DON on mitochondrial metabolism, proliferation and goblet cell functions. Taken together, our results demonstrate that the bacterial metabolite butyrate is able to reduce DON-induced epithelial barrier disruption.

This study investigates the use of Moringa Leaf Powder (MLP) and Vitamin C in the diets of broiler chickens exposed to Aflatoxin B1 (AFB1) to enhance performance and health. Two hundred one-day old Cobb 500 broiler breed chicks were divided into four diet groups: CON (no AFB1, no MLP), AFB (0.2 mg AFB1 per kg of feed), AFV (0.2 mg AFB1 with 200 mg vitamin C), and AFM (0.2 mg AFB1 with 500 mg MLP). Supplementation with MLP and vitamin C led to improved broiler performance, with AFM and AFV groups exhibiting higher body weight gain, similar or lower feed intake, and better feed conversion ratios compared to AFB. Mortality rates were lower in AFM and AFV, and dressing percentages and liver weights were higher. Haematological parameters showed significant improvements in AFM and AFV compared to AFB. MLP and vitamin C reduced serum cholesterol levels and normalised liver enzymes. MLP improved kidney function. Using 200 mg kg-1 vitamin C or 500 mg kg-1 Moringa oleifera powder as dietary supplements for broiler chickens exposed to aflatoxin B1 is recommended for improved productivity and health.

Knowledge of the biological properties of bacterial toxins is constantly being updated. Over the past two decades, the research interest has shifted from natural toxins to their genetically modified derivatives. The purpose of the work is to summarize the knowledge of the biological properties of bacterial toxins accumulated in the English-language scientific literature in recent years. The research method is analytical. The source base for the research is Englishlanguage scientific literature, accessible through the global Internet. Results. The work examines: the organization and general mechanism of action of bacterial toxin molecules; the reliability of their toxicity indicators given in the scientific literature; toxic effects of toxins of various groups, differing in their mechanism of action; obtaining hybrid and modified toxins; identification of artificial toxins. Conclusions. Among bacterial toxins, binary toxins are the most dangerous. The binary composition of bacterial exotoxins, a good understanding of their subunits, functional domains, assembly mechanisms and intracellular action, make it possible to modify them in the direction of changing the range of targets, toxicity, mechanism of damaging action and immunogenicity. To identify genetically modified toxins, poorly studied analogues and isoforms of natural toxins, special programs based on machine learning can be used.