A-toxin

Caenorhabditis elegans is a useful model organism to study the xenobiotic detoxification pathways of various natural and synthetic toxins, but the mechanisms of phase II detoxification are understudied. 1-Hydroxyphenazine (1-HP), a toxin produced by the bacterium Pseudomonas aeruginosa , kills C. elegans . We previously showed that C. elegans detoxifies 1-HP by adding one, two, or three glucose molecules in N2 worms. Our current study evaluates the roles that some UDP-glycosyltransferase ( ugt ) genes play in 1-HP detoxification...

Snakebite envenomation is a life-threatening condition and antivenoms are used as the most effective treatment. Venom obtained from snakes in long-term captivity showed some variations in comparison to the venom of the wild snakes. The objective of this study is to compare the venom of the Pseudocerastes persicus under long-term captivity and wild conditions as well as the antivenom obtained from these venoms. We have analyzed venom samples and produced trivalent antivenoms using the venom of long-term captive (LTC) or recently wild-captured (RWC) Pseudocerastes persicus, and RWC Macrovipera lebetina, and Echis carinatus...

Bacteria and archaea respond and adapt to environmental stress conditions by modulating the toxin-antitoxin (TA) system for survival. Within the bacterium Helicobacter pylori , the protein HP0894 is a key player in the HP0894-HP0895 TA system, in which HP0894 serves as a toxin and HP0895 as an antitoxin. HP0894 has intrinsic ribonuclease (RNase) activity that regulates gene expression and translation, significantly influencing bacterial physiology and survival. This activity is influenced by the presence of metal ions such as Mg2+ ...

Proteinaceous toxins are peptides or proteins that hold great biotechnological value, evidenced by their ecological role, whether as defense or predation mechanisms. Bioprospecting using bioinformatics and omics may render screening for novel bioactives more expeditious, especially considering the immense diversity of toxin-secreting marine organisms. Eulalia sp. (Annelida: Phyllodocidae), a toxin bearing marine annelid, was recently shown to secrete cysteine-rich protein (Crisp) toxins (hitherto referred to as 'phyllotoxins') that can immobilize its prey...

While the unique symbiotic relationship between anemonefishes and sea anemones is iconic, it is still not fully understood how anemonefishes can withstand and thrive within the venomous environment of their host sea anemone. In this study, we used a proteotranscriptomics approach to elucidate the proteinaceous toxin repertoire from the most common host sea anemone, Entacmaea quadricolor . Although 1251 different toxin or toxin-like RNA transcripts were expressed in E. quadricolor tentacles (0.05% of gene clusters, 1...

As evaluation indicators of the primary productivity, the phytoplankton biomass and community structure are of great significance to the fishery industry, which can be driven by ocean currents, nutrients and water stratification. In the present study, the characteristics of phytoplankton assemblages in different water layers of a typical Yesso scallop farming area in Zhangzi Island, the North Yellow Sea were investigated from March 2021 to January 2022. According to the vertical distribution of temperature, water stratification was observed from June to August (stratification period), and disappeared in March, October and the following January with vertical homogeneity (mixing period)...

Microcystin-LR (MIC-LR) is a toxin which the mechanism of intoxication involves oxidative stress. Urolithin A (URO-A) is a metabolic from colonic fermentation of ellagic acid with antioxidant potential. This study aimed to evaluate the putative protective effect of URO-A against MIC-LR toxicity in C6 cells. C6 cells were incubated with MIC-LR (1 and 10 μM) and/or URO-A (3, 30, 60 and 100 μM) for 24h. MIC-LR induced reactive species (RS) generation, depletion in total thiol (SH) groups and survival loss when compared with control group...

The recommended treatment for post-exposure prophylaxis (PEP) following known/suspected exposure to Bacillus anthracis involves immunization with anthrax vaccine adsorbed (AVA, i.e., BioThrax® vaccine) and a course of antimicrobial therapy. A drug-vaccine interaction clinical trial was conducted to determine whether this combined treatment might modify antimicrobial exposure or vaccine immunogenicity. A Phase 2, randomized, open-label, multi-center trial involving 154 healthy adult participants was completed to evaluate the effect of AVA immunization (three doses administered subcutaneously (SC) at weeks 0, 2 and 4) on the pharmacokinetics (PK) of ciprofloxacin, as well as the effect of ciprofloxacin administration (500 mg po bid) on the immunogenicity of AVA...

The castor plant (Ricinus communis) is primarily known for its seeds, which contain a unique fatty acid called ricinoleic acid with several industrial and commercial applications. Castor seeds also contain ricin, a toxin considered a chemical and biological warfare agent. Despite years of investigation, there is still no effective antidote or vaccine available. However, some progress has been made, and the development of an effective treatment may be on the horizon. To provide an updated overview of this issue, we have conducted a comprehensive review of the literature on the current state of research in the fight against ricin...

Cytolethal distending toxins (CDTs) are released by Gram-negative pathogens into the extracellular medium as free toxin or associated with extracellular vesicles (EVs), commonly known as outer membrane vesicles (OMVs). CDT production by the gastrointestinal pathogen Campylobacter jejuni has been implicated in colorectal tumorigenesis. Despite CDT being a major virulence factor for C. jejuni , little is known about the EV-associated form of this toxin. To address this point, C. jejuni mutants lacking each of the three CDT subunits (A, B, and C) were generated...

Mosquitoes of the Culex pipiens complex are worldwide vectors of arbovirus, filarial nematodes, and avian malaria agents. In these hosts, the endosymbiotic bacteria Wolbachia induce cytoplasmic incompatibility (CI), i.e., reduced embryo viability in so-called incompatible crosses. Wolbachia infecting Culex pipiens (wPip) cause CI patterns of unparalleled complexity, associated with the amplification and diversification of cidA and cidB genes, with up to 6 different gene copies described in a single wPip genome...

This study aimed at assessing a new line of treatment for lifelong premature ejaculation which is botulinum-A toxin injection into the bulbospongiosus muscle. Sixty patients with lifelong premature ejaculation were independently randomized into 2 groups; group I, 100 U botulinum-A toxin at 10 U/ml saline was injected with ultrasound guidance into the bulbospongiosus muscle and group II which was injected with similar volume of saline. The primary outcome was to compare both groups for changes in the Premature Ejaculation Profile (PEP), Intravaginal Ejaculatory Latency Time (IELT) and partner's satisfaction at 1, 3 and 6 months after intervention...

Trichophyton mentagrophytes is increasingly considered to be a public health hazard because it causes the most severe manifestations of dermatophytosis. In this study, we performed a series of studies to determine the pathogenicity of the T. mentagrophytes complex. We show that the T. mentagrophytes complex interacts with keratinocytes through pattern-recognition receptors‒MAPK/noncanonical NF-κB pathways and that the hyphal form of T. mentagrophytes is responsible for the increased inflammatory responses in keratinocytes...

A 41-year-old man developed rapidly progressive cranial neuropathies and muscle weakness followed by respiratory failure, requiring ventilation support. On examination, there was marked bilateral ptosis and ophthalmoplegia with bulbar, neck and proximal upper limb weakness. He had a recent open left humeral fracture that eventually required amputation. Despite immunoglobulin therapy, his progressive weakness continued. Multiple investigation results were inconclusive. Eventually, botulinum type A toxin was found positive, by which time the therapeutic window for antitoxin had passed...

The endosymbiotic bacteria Wolbachia can invade insect populations by modifying host reproduction through cytoplasmic incompatibility (CI), an effect that results in embryonic lethality when Wolbachia-carrying males mate with Wolbachia-free females. Here we describe a transgenic system for recreating CI in the major arbovirus vector Aedes aegypti using CI factor (cif) genes from wAlbB, a Wolbachia strain currently being deployed to reduce dengue transmission. CI-like sterility is induced when cifA and cifB are co-expressed in testes; this sterility is rescued by maternal cifA expression, thereby reproducing the pattern of Wolbachia-induced CI...

Bacteria and the viruses that infect them (bacteriophages or phages) are engaged in an evolutionary arms race that has resulted in the development of hundreds of bacterial defense systems and myriad phage-encoded counterdefenses 1-5 . While the mechanisms of many bacterial defense systems are known 1 , how these systems avoid toxicity outside infection yet activate quickly upon sensing phage infection is less well understood. Here, we show that the bacterial P hage A nti- R estriction- I nduced S ystem (PARIS) operates as a toxin-antitoxin system, in which the antitoxin AriA sequesters and inactivates the toxin AriB until triggered by the T7 phage counterdefense protein Ocr...

Microcystin-LR (MC-LR) is a toxin produced by cyanobacteria, which is widely distributed in eutrophic water bodies and has multi-organ toxicity. Previous cytotoxicity studies have mostly elucidated the effects of MC-LR on intracellular-related factors, proteins, and DNA at the molecular level. However, there have been few studies on the adverse effects of MC-LR on cell ultrastructure and function. Therefore, research on the cytotoxicity of MC-LR in recent years was collected and summarized. It was found that MC-LR can induce a series of cytotoxic effects, including decreased cell viability, induced autophagy, apoptosis and necrosis, altered cell cycle, altered cell morphology, abnormal cell migration and invasion as well as leading to genetic damage...

Cetaceans are well-regarded as sentinels for toxin exposure. Emerging studies suggest that cetaceans can also develop neuropathological changes associated with neurodegenerative disease. The occurrence of neuropathology makes cetaceans an ideal species for examining the impact of marine toxins on the brain across the lifespan. Here, we describe TAR DNA-binding protein 43 (TDP-43) proteinopathy and Alzheimer's disease (AD) neuropathological changes in a beached harbor porpoise ( Phocoena phocoena ) that was exposed to a toxin produced by cyanobacteria called β-N-methylamino-L-alanine (BMAA)...

Acrylamide (ACR), a toxin present in fried and baked carbohydrate-rich foods, is known to cause liver and kidney damage. This study aimed to investigate the mechanisms of oxidative stress, inflammation, and apoptosis that contribute to liver and kidney damage induced by chronic administration of ACR. Additionally, the effectiveness of vitamin E in mitigating these toxic effects was examined. The study initially involved dividing 40 pregnant rats into four groups. After lactation, the research continued with male offspring rats from each group...

Improved therapies are needed against snakebite envenoming, which kills and permanently disables thousands of people each year. Recently developed neutralizing monoclonal antibodies against several snake toxins have shown promise in preclinical rodent models. Here, we use phage display technology to discover a human monoclonal antibody and show that this antibody causes antibody-dependent enhancement of toxicity (ADET) of myotoxin II from the venomous pit viper, Bothrops asper, in a mouse model of envenoming that mimics a snakebite...