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Tetanus is a toxigenic illness caused by the action of Clostridium tetani neurotoxin (TeNT), which results in partial or generalized muscle stiffness in infected mammals and birds. The disease is rarely reported in cats due to their innate resistance to the toxin. This multicentric retrospective study aimed to describe a significant population of cats with a diagnosis of tetanus and report their signalment, clinical and neurological signs, diagnostic findings, treatment, and outcome. A retrospective search through medical records from 11 referral centers in Europe resulted in the identification of 27 cases of feline tetanus from July 2005 to April 2023. These cases were further compared with previously reported cases in the veterinary literature. Young cats were more commonly represented than older cats, with a median age of 4 years. Clinical signs were initially characterized by a lame and/or stiff limb, near the primary injury site, in 17/26 (65%) cats. Signs were focal or multifocal in 21/27 (78%) cats of this study and one typical sign was the inability to flex the most severely affected limbs. Electrodiagnostic studies revealed characteristic changes, such as continuous spontaneous motor unit discharges in both agonist and antagonist muscles. Such studies are particularly useful in focal and multifocal cases and should be performed to further support the diagnosis. The toxin was successfully identified in one case using the mouse bioassay. Treatment included antibiotherapy (metronidazole) in most cases, muscle relaxants, appropriate nursing cares and handling of potential complications. Overall, the outcome appeared to be positive, with only 1/27 (3.7%) cats being euthanized due to financial restrains. 23/25 (92%) cats returned to an independent ambulatory capacity on all limbs within a median delay of 25 days. Mild to moderate longterm sequelae were reported in eight (30%) cats. This multicentric study is the first to bring together such a large number of cats affected with tetanus. Presentation of the disease in cats differs from that observed in humans and dogs, with most cats being locally affected. Compared to previous reports of tetanus, this series of cats had a better outcome overall, especially for cats affected with generalized tetanus. [ABSTRACT FROM AUTHOR]

Onabotulinum Toxin-A (BTX-A) is a second-line treatment for neurogenic bladder (NB). It requires repeated injections over time, which is a possible limit for long-term adherence, especially in children, as general anesthesia is required. Almost 50% of adults discontinue therapy; few data on pediatric patients are present. The aim of this study is to share our long-term experience of BTX-A adherence in children. This study is a retrospective review of 230 refractory NB patients treated with BTX-A. The inclusion criteria were ≥3 treatments and the first injection performed ≥10 years before the study endpoint. Fifty-four patients were included. Mean follow-up was 10.2 years; mean treatment number was 6.4 for each patient. During follow-up, 7% did not need BTX-A anymore; 76% discontinued therapy, with a prevalence of acquired NB (64% acquired vs. 34% congenital; p = 0.03); sex-based and urodynamic findings did not influence the discontinuation rate (p = 0.6, p = 0.2, respectively). Considering those who withdrew from the therapy, 43% were lost to follow-up/died after a mean of 7.5 years (although 33% still experienced clinical efficacy); 33% changed therapy after a mean of 5.8 years (with reduced efficacy in 22%, persistent efficacy in 11%). BTX-A is a safe and effective therapy for pediatric patients. The treatment abandonment rate is higher for children than for adults; no specific reasons were highlighted. It is necessary to evaluate any age-specific factors to explain these data. [ABSTRACT FROM AUTHOR]

Abstract Cyanobacteria produce neurotoxic non-protein amino acids (NPAAs) that accumulate in ecosystems and food webs. American lobsters (Homarus americanus H. Milne-Edwards) are one of the most valuable seafood industries in Canada with exports valued at > $2 billion. Two previous studies have assessed the occurrence of β-N-methylamino-L-alanine (BMAA) in a small number of lobster tissues but a complete study has not previously been undertaken. We measured NPAAs in eyeballs, brain, legs, claws, tails, and eggs of 4 lobsters per year for the 2021 and 2022 harvests. Our study included 4 male and 4 female lobsters. We detected BMAA and its isomers, N-(2-aminoethyl)glycine (AEG), 2,4-diaminobutyric acid (DAB) and β-aminomethyl-L-alanine (BAMA) by a fully validated reverse phase chromatography—tandem mass spectrometry method. We quantified BMAA, DAB, AEG and BAMA in all of the lobster tissues. Our quantification data varied by individual lobster, sex and collection year. Significantly more BMAA was quantified in lobsters harvested in 2021 than 2022. Interestingly, more BAMA was quantified in lobsters harvested in 2022 than 2021. Monitoring of lobster harvests for cyanobacterial neurotoxins when harmful algal bloom events occur could mitigate risks to human health.

The larvae of some lampyrid beetles are highly specialized predators of snails. They have been observed to climb on the shells of their prey and use this exposed position to bite and inject secretions potentially originating from the midgut. Besides serving the purpose of extra-oral digestion (EOD), injected compounds also seem to have a paralyzing effect. Up to now, the toxins causing this paralyzing activity have not been identified. In the current study, we provide a first compositional analysis of the midgut secretion from lampyrid larvae, with a focus on identifying putative neurotoxins causing the observed paralyzing effect. For this purpose, we utilized a combined proteo-transcriptomic approach to characterize the compounds present in the midgut secretion of larval stages of Lampyris noctiluca. In terms of the absolute numbers of identified compounds, the midgut secretion is dominated by hydrolyzing enzymes comprising peptidases, carboxylesterases, and glycosidases. However, when considering expression levels, a few rather short cysteine-rich peptides exceed all other compounds. Some of these compounds show moderate similarity to putative neurotoxins identified in the venom of other arthropods and could be responsible for paralyzing effects. In addition to these potential toxins, we provide a list of peptides typical of the midgut secretion of L. noctiluca, supplemented by the corresponding precursor sequences. [ABSTRACT FROM AUTHOR]

This retrospective, observational study describes the clinical findings, case management trends, and outcomes of 83 dogs and nine cats exposed to eastern coral snakes in a university teaching hospital setting. The medical records of dogs and cats that received antivenom following coral snake exposure were reviewed. Data collected included signalment, time to antivenom administration, physical and laboratory characteristics at presentation, clinical course during hospitalization, length of hospitalization, and survival to discharge. The mean time from presentation to coral snake antivenom administration was 2.26 ± 1.46 h. Excluding cases where the owner declined in-hospital care, the mean hospitalization time for dogs and cats was 50.8 h and 34 h, respectively. The mean number of antivenom vials was 1.29 (1–4). Gastrointestinal signs (vomiting and ptyalism) occurred in 42.2% (35/83) of dogs and 33.3% (3/9) of cats. Peripheral neurologic system deficits (ataxia, paresis to plegia, absent reflexes, and hypoventilation) were noted in 19.6% (18/92) of dogs and cats. Hemolysis was also common in 37.9% (25/66) of dogs but was not observed in cats. Mechanical ventilation (MV) was indicated in 12% (10/83) of dogs but no cats. Acute kidney injury (AKI), while rare, was a common cause of euthanasia at 20% (2/5) and was the most common complication during MV at 44.4% (4/9). Pigmenturia/hemolysis occurred in 88.9% (8/9) of MV cases and in all cases with AKI. Despite delays in antivenom administration by several hours, dogs and cats with coral snake exposure have low mortality rates (6% of dogs (5/83) and 0% of cats). Gastrointestinal signs were common but were not predictive of progression to neurological signs. Thus, differentiating between coral snake exposure and envenomation before the onset of neurological signs remains challenging. [ABSTRACT FROM AUTHOR]

The pathophysiology of Lyme disease, especially in its persistent form, remains to be determined. As many of the neurologic symptoms are similar to those seen in other toxin-associated disorders, a hypothesis was generated that B. burgdorferi, the causative agent of Lyme disease, may produce a neurotoxin to account for some of the symptoms. Using primers against known conserved bacterial toxin groups, and PCR technology, a candidate neurotoxin was discovered. The purified protein was temporarily named BbTox, and was subsequently found to be identical to BB0755, a protein deduced from the genome sequence of B. burgdorferi that has been annotated as a Z ribonuclease. BbTox has cytotoxic activity against cells of neural origin in tissue culture. Its toxic activity appears to be directed against cytoskeletal elements, similar to that seen with toxins of Clostridioides difficile and Clostridioides botulinum, but differing from that of cholera and E. coli toxins, and other toxins. It remains to be determined whether BbTox has direct cytotoxic effects on neural or glial cells in vivo, or its activity is primarily that of a ribonuclease analogous to other bacterial ribonucleases that are involved in antibiotic tolerance remains to be determined. [ABSTRACT FROM AUTHOR]

Objectives: Aluminium (Al) is also a popular neurotoxin that accelerates oxidative damage to biomolecules, which is correlated to the aetiology of Alzheimer's disease (AD). It is a common metal on the globe and can easily enter the body through food and water additives, cutlery, deodorants, and medications. It accumulates mostly in the brain's frontal cortex and hippocampus, and its elimination half-life in the human brain is estimated to be 7 years. It is known to be particularly vulnerable to AD, which is a crippling neurological ailment that primarily affects ageing adults and has a large socioeconomic impact. Niruriflavone (NF) is a natural flavonoid isolated from Phyllanthus niruri Linn. It demonstrated remarkable neuroprotective efficacy by inhibiting oxidative stress, acetylcholinesterase (AChE), and 5-lipoxygenase. The efficacy of NF was improved by the formulation of NF-loaded chitosan nanoparticle (NFLC). Consequently, the current study sought to assess the neuroprotective role of synthesized NFLC against aluminium chloride (AlCl3)-induced AD through the neurobehavioural, biochemical, and histopathological analysis. Methods: Chronic administration of 100 mg/kg body weight of AlCl3 orally to Wistar rats resulted in AD. Neurobehavioural tests such the open-field test, elevated plus maze tests, and Morris water maze were used to evaluate the impact of NFLC treatment. The activity of the acetylcholinesterase enzyme and level of aluminium were also measured in AlCl3-induced AD rats. Cresyl violet staining was used to study the histopathological variations. Results: NFLC treatment considerably increased learning and memory skills, improved the exploratory activities, and reduced the anxiety-related behaviour. NFLC-treated rats had lower Al levels and higher AChE inhibition activity. NFLC prevented the neuronal loss in the AD rat brains which was observed in histopathological studies. Conclusion: NFLC helps to treat AD brought on by Al poisoning through the inhibition of AChE activity, oxidative stress, neuroinflammation, and neuronal loss. The development of these efficacious multitargeted NFLC could help people afflicted by AD. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a predominant neuromotor disorder characterized by the selective death of dopaminergic neurons in the midbrain. The majority of PD cases are sporadic or idiopathic, with environmental toxins and pollutants potentially contributing to its development or exacerbation. However, clinical PD patients are often associated with a reduced stroke frequency, where circulating blood platelets are indispensable. Although platelet structural impairment is evident in PD, the platelet functional alterations and their underlying molecular mechanisms are still obscure. Therefore, we investigated rotenone (ROT), an environmental neurotoxin that selectively destroys dopaminergic neurons mimicking PD, on human blood platelets to explore its impact on platelet functions, thus replicating PD conditions in vitro. Our study deciphered that ROT decreased thrombin‐induced platelet functions, including adhesion, activation, secretion, and aggregation in human blood platelets. As ROT is primarily responsible for generating intracellular reactive oxygen species (ROS), and ROS is a key player regulating the platelet functional parameters, we went on to check the effect of ROT on platelet ROS production. In our investigation, it became evident that ROT treatment resulted in the stimulation of ROS production in human blood platelets. Additionally, we discovered that ROT induced ROS production by augmenting Ca2+ mobilization from inositol 1,4,5‐trisphosphate receptor. Apart from this, the treatment of ROT triggers protein kinase C associated NADPH oxidase‐mediated ROS production in platelets. In summary, this research, for the first time, highlights ROT‐induced abnormal platelet functions and may provide a mechanistic insight into the altered platelet activities observed in PD patients. [ABSTRACT FROM AUTHOR]

Bacterial protein toxins are secreted by certain bacteria and are responsible for mild to severe diseases in humans and animals. They are among the most potent molecules known, which are active at very low concentrations. Bacterial protein toxins exhibit a wide diversity based on size, structure, and mode of action. Upon recognition of a cell surface receptor (protein, glycoprotein, and glycolipid), they are active either at the cell surface (signal transduction, membrane damage by pore formation, or hydrolysis of membrane compound(s)) or intracellularly. Various bacterial protein toxins have the ability to enter cells, most often using an endocytosis mechanism, and to deliver the effector domain into the cytosol, where it interacts with an intracellular target(s). According to the nature of the intracellular target(s) and type of modification, various cellular effects are induced (cell death, homeostasis modification, cytoskeleton alteration, blockade of exocytosis, etc.). The various modes of action of bacterial protein toxins are illustrated with representative examples. Insights in toxin evolution are discussed. [ABSTRACT FROM AUTHOR]

Background: Vaginismus, a prevalent genito-pelvic pain/penetration disorder in the Middle East, often leads to unconsummated marriages, with a significant impact on marital and social well-being. Traditional treatments have shown limited success in refractory cases. Objective: To evaluate the effectiveness of an integrated treatment program, including Botulinum Toxin A (BTXA) injections, gradual vaginal introitus dilation, and psychological support, in treating refractory vaginismus in Egyptian women. Patients and Methods: This retrospective case series analyzed 1,400 women with refractory vaginismus, treated between January 2013 and 2023. The program comprised BTXA injections in the perineal muscles, followed by guided physiotherapy for muscle dilation and psychological counseling. Success was defined as painless vaginal penetration. Results: Of the initial 1,512 cases, 1,400 completed the program. The average age of participants was 28 years. Most patients (93%) had tried conventional treatments without success. Post-treatment, 92.6% (1,288/1,400) achieved painless penetration. The majority required 3 to 5 dilatation treatment sessions for success. Mild adverse effects were reported in 28% of cases. Conclusion: The integrated treatment program, combining BTXA injections, gradual dilation, and psychological support, is highly effective in managing refractory vaginismus in Egyptian women, with a success rate of over 90%. This approach offers a promising solution for couples facing unconsummated marriages due to vaginismus. [ABSTRACT FROM AUTHOR]

Parkinson's disease is a complex neurodegenerative disease characterized by progressive movement impairments. Predominant symptoms encompass resting tremor, bradykinesia, limb rigidity, and postural instability. In addition, it also includes a series of non-motor symptoms such as sleep disorders, hyposmia, gastrointestinal dysfunction, autonomic dysfunction and cognitive impairment. Pathologically, the disease manifests through dopaminergic neuronal loss and the presence of Lewy bodies. At present, no significant breakthrough has been achieved in clinical Parkinson's disease treatment. Exploring treatment modalities necessitate the establishment of scientifically sound animal models. In recent years, researchers have focused on replicating the symptoms of human Parkinson's disease, resulting in the establishment of various experimental animal models primarily through drugs and transgenic methods to mimic relevant pathologies and identify more effective treatments. This review examines traditional neurotoxin and transgenic animal models as well as α-synuclein pre-formed fibrils models, non-human primate models and non-mammalian specie models. Additionally, it introduces emerging models, including models based on optogenetics, induced pluripotent stem cells, and gene editing, aiming to provide a reference for the utilization of experimental animal models and clinical research for researchers in this field.

Tetanus is a toxigenic illness caused by the action of Clostridium tetani neurotoxin (TeNT), which results in partial or generalized muscle stiffness in infected mammals and birds. The disease is rarely reported in cats due to their innate resistance to the toxin. This multicentric retrospective study aimed to describe a significant population of cats with a diagnosis of tetanus and report their signalment, clinical and neurological signs, diagnostic findings, treatment, and outcome. A retrospective search through medical records from 11 referral centers in Europe resulted in the identification of 27 cases of feline tetanus from July 2005 to April 2023. These cases were further compared with previously reported cases in the veterinary literature. Young cats were more commonly represented than older cats, with a median age of 4 years. Clinical signs were initially characterized by a lame and/or stiff limb, near the primary injury site, in 17/26 (65%) cats. Signs were focal or multifocal in 21/27 (78%) cats of this study and one typical sign was the inability to flex the most severely affected limbs. Electrodiagnostic studies revealed characteristic changes, such as continuous spontaneous motor unit discharges in both agonist and antagonist muscles. Such studies are particularly useful in focal and multifocal cases and should be performed to further support the diagnosis. The toxin was successfully identified in one case using the mouse bioassay. Treatment included antibiotherapy (metronidazole) in most cases, muscle relaxants, appropriate nursing cares and handling of potential complications. Overall, the outcome appeared to be positive, with only 1/27 (3.7%) cats being euthanized due to financial restrains. 23/25 (92%) cats returned to an independent ambulatory capacity on all limbs within a median delay of 25 days. Mild to moderate long-term sequelae were reported in eight (30%) cats. This multicentric study is the first to bring together such a large number of cats affected with tetanus. Presentation of the disease in cats differs from that observed in humans and dogs, with most cats being locally affected. Compared to previous reports of tetanus, this series of cats had a better outcome overall, especially for cats affected with generalized tetanus.

Peripheral autonomic nervous system (P-ANS) dysfunction is a critical non-motor phenotype of Parkinson's disease (PD). The majority of PD cases are sporadic and lack identified PD-associated genes involved. Epidemiological and animal model studies suggest an association with pesticides and other environmental toxins. However, the cellular mechanisms underlying toxin induced P-ANS dysfunctions remain unclear. Here, we mapped the global transcriptome changes in human induced pluripotent stem cell (iPSC) derived P-ANS sympathetic neurons during inhibition of the mitochondrial respiratory chain by the PD-related pesticide, rotenone. We revealed distinct transcriptome profiles between acute and chronic exposure to rotenone. In the acute stage, there was a down regulation of specific cation channel genes, known to mediate electrophysiological activity, while in the chronic stage, the human P-ANS neurons exhibited dysregulation of anti-apoptotic and Golgi apparatus-related pathways. Moreover, we identified the sodium voltage-gated channel subunit SCN3A/Nav1.3 as a potential biomarker in human P-ANS neurons associated with PD. Our analysis of the rotenone-altered coding and non-coding transcriptome of human P-ANS neurons may thus provide insight into the pathological signaling events in the sympathetic neurons during PD progression. [Display omitted] • A human model of the peripheral autonomic nervous system (P-ANS) in Parkinson's disease (PD) was developed. • Inhibiting the mitochondrial electron transport chain by rotenone alters specific transcriptional networks in P-ANS neurons. • In these neurons, several cation channels including SCN3A associated with excitability are downregulated by rotenone. • A new repertoire of non-coding genes that may be related to PD was identified in P-ANS neurons. [ABSTRACT FROM AUTHOR]

The interplay between predator and prey has catalyzed the evolution of venom systems, with predators honing their venoms in response to the evolving resistance of prey. A previous study showed that the African varanid species Varanus exanthematicus has heightened resistance to snake venoms compared to the Australian species V. giganteus, V. komodoensis, and V. mertensi, likely due to increased predation by sympatric venomous snakes on V. exanthematicus. To understand venom resistance among varanid lizards, we analyzed the receptor site targeted by venoms in 27 varanid lizards, including 25 Australian varanids. The results indicate an active evolutionary arms race between Australian varanid lizards and sympatric neurotoxic elapid snakes. Large species preying on venomous snakes exhibit inherited neurotoxin resistance, a trait potentially linked to their predatory habits. Consistent with the 'use it or lose it' aspect of venom resistance, this trait was secondarily reduced in two lineages that had convergently evolved gigantism (V. giganteus and the V. komodoensis/V. varius clade), suggestive of increased predatory success accompanying extreme size and also increased mechanical protection against envenomation due to larger scale osteoderms. Resistance was completely lost in the mangrove monitor V. indicus, consistent with venomous snakes not being common in their arboreal and aquatic niche. Conversely, dwarf varanids demonstrate a secondary loss at the base of the clade, with resistance subsequently re-evolving in the burrowing V. acanthurus/V. storri clade, suggesting an ongoing battle with neurotoxic predators. Intriguingly, within the V. acanthurus/V. storri clade, resistance was lost again in V. kingorum, which is morphologically and ecologically distinct from other members of this clade. Resistance was also re-evolved in V. glebopalma which is terrestrial in contrast to the arboreal/cliff dwelling niches occupied by the other members of its clade (V. glebopalma, V. mitchelli, V. scalaris, V. tristis). This 'Russian doll' pattern of venom resistance underscores the dynamic interaction between dwarf varanids and Australian neurotoxic elapid snakes. Our research, which included testing Acanthophis (death adder) venoms against varanid receptors as models for alpha-neurotoxic interactions, uncovered a fascinating instance of the Red Queen Hypothesis: some death adders have developed more potent toxins specifically targeting resistant varanids, a clear sign of the relentless predator–prey arms race. These results offer new insight into the complex dynamics of venom resistance and highlight the intricate ecological interactions that shape the natural world. [ABSTRACT FROM AUTHOR]

In accidents involving Crotalus snakes, the crotoxin complex (CTX) plays lethal action due to its neurotoxic activity. On the other hand, CTX have potential biotechnological application due to its anti-tumoral, anti-inflammatory, antimicrobial, analgesic and immunomodulatory properties. CTX is a heterodimer composed of Crotoxin A (CA or crotapotin), the acidic nontoxic and non-enzymatic component and; Crotoxin B (CB), a basic, toxic and catalytic PLA 2. Currently, there are two classes of CTX isoforms, whose differences in their biological activities have been attributed to features presented in CB isoforms. Here, we present the crystal structure of CB isolated from the Crotalus durissus collilineatus venom. It amino acid sequence was assigned using the SEQUENCE SLIDER software, which revealed that the crystal structure is a heterodimer composed of two new CB isoforms (col CB-A and col CB-B). Bioinformatic and biophysical analyses showed that the toxin forms a tetrameric assembly in solution similar to CB from Crotalus durissus terrificus venom, despite some differences observed at the dimeric interface. By the previously proposed classification, the col CB-B presents features of the class I isoforms while col CB-A cannot be classified into classes I and II based on its amino acid sequence. Due to similar features observed for other CB isoforms found in the NCBI database and the results obtained for col CB-A, we suggest that there are more than two classes of CTX and CB isoforms in crotalic venoms. • The crystal structure of CB from C. d. collilineatus venom was obtained. • Crystal structure is a heterodimer composed of two new CB isoforms. • Bioinformatic and biophysical analyses showed that the toxin is tetrameric. • col CB-A isoform cannot be classified into classes I and II based on its sequence. • We hypothesized that there are more than two classes of CB isoforms. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the effect of botulinum toxin-A (BoNT-A) on the age groups and gross motor function classification level in children with cerebral palsy (CP). Method: In this study, 116 children with spastic CP were investigated. BoNT-A was injected into the spastic muscles of the lower limbs of all participants. All participants received physiotherapy and functional electrical stimulation for 3 months after injection. We measured the change in spasticity using the Modified Ashworth Scale and gross motor function using the GMFM-88. Spasticity was measured before injection and at 1 and 3 months after injection. Measurement of gross motor function was performed before and after the injections. Results: The effect of BoNT-A injection in combination with physiotherapy and electrical stimulation significantly improved spasticity and gross motor function. After BoNT-A injection, younger children showed reduced spasticity and improved gross motor skills compared to older children. At the gross motor level, sitting, standing, and walking improved in children with gross motor function classification levels I-III, and posture and mobility improved in children with gross motor function classification levels IV-V. Conclusions: We conclude that BoNT-A injection is effective for improving gross motor function in patients younger than 72 months of age.

Abstract Two sheep presented with acute tonic‐clonic seizures, opisthotonos, absent pupillary light reflexes and abnormal vital signs within 18 hours after observed consumption of leaves from an ornamental shrub later identified as wintersweet (Chimonanthus praecox). Despite symptomatic treatment, both sheep died. Three other sheep that consumed the plant died after displaying similar clinical signs, resulting in 2 deaths the prior evening and 1 recovery the next morning. Gross necropsy and histologic findings were diagnostically inconclusive. Rumen contents tested positive for the alkaloid calycanthine, a centrally‐acting convulsant known to be present in wintersweet. Case reports of calycanthine toxicity in ruminants are limited, with no detailed reports published in the United States. Calycanthine has been isolated from the seeds, flowers, and leaves of the plant. Wintersweet is part of the family Calycanthaceae that including 3 species native to North America, all of which pose a neurologic risk to ruminants if consumed.

Onabotulinum Toxin-A (BTX-A) is a second-line treatment for neurogenic bladder (NB). It requires repeated injections over time, which is a possible limit for long-term adherence, especially in children, as general anesthesia is required. Almost 50% of adults discontinue therapy; few data on pediatric patients are present. The aim of this study is to share our long-term experience of BTX-A adherence in children. This study is a retrospective review of 230 refractory NB patients treated with BTX-A. The inclusion criteria were ≥3 treatments and the first injection performed ≥10 years before the study endpoint. Fifty-four patients were included. Mean follow-up was 10.2 years; mean treatment number was 6.4 for each patient. During follow-up, 7% did not need BTX-A anymore; 76% discontinued therapy, with a prevalence of acquired NB (64% acquired vs. 34% congenital; p = 0.03); sex-based and urodynamic findings did not influence the discontinuation rate (p = 0.6, p = 0.2, respectively). Considering those who withdrew from the therapy, 43% were lost to follow-up/died after a mean of 7.5 years (although 33% still experienced clinical efficacy); 33% changed therapy after a mean of 5.8 years (with reduced efficacy in 22%, persistent efficacy in 11%). BTX-A is a safe and effective therapy for pediatric patients. The treatment abandonment rate is higher for children than for adults; no specific reasons were highlighted. It is necessary to evaluate any age-specific factors to explain these data.

Background: Subcutaneous mastectomies in transmen have been gaining popularity. However, post-operative scars are an inevitable consequence. Recently, Botulinum neurotoxin A (BoNT-A) has shown positive effects in scar prevention. The objective of this study is to investigate the effectiveness of BoNT-A in scar prevention. Methods: Fifteen patients who had undergone subcutaneous mastectomy were included. At 14 days post-surgery, either incoBoNT-A or a placebo was injected into the scar on each side. The primary outcome assessment measured the scar's severity using the Vancouver Scar Scale (VSS) and the Patient and Observer Scar Assessment Scale (POSAS). The secondary outcome assessment evaluated the scar's color using a standard measurement device. Outcome assessments were conducted until 6 months post-surgery. Results: There were significantly lower VSS scores in the BoNT-A group compared to the placebo at the end of the study (7.43 ± 0.26 vs. 8.82 ± 0.26, p < 0.001). The objective assessment revealed a statistically significant decrease in redness values in the BoNT-A group compared to the placebo at 3 and 6 months. Conclusion: BoNT-A has demonstrated effectiveness in scar prevention by reducing the severity of postoperative scar formation and improving overall scar appearance. [ABSTRACT FROM AUTHOR]

Two sheep presented with acute tonic‐clonic seizures, opisthotonos, absent pupillary light reflexes and abnormal vital signs within 18 hours after observed consumption of leaves from an ornamental shrub later identified as wintersweet (Chimonanthus praecox). Despite symptomatic treatment, both sheep died. Three other sheep that consumed the plant died after displaying similar clinical signs, resulting in 2 deaths the prior evening and 1 recovery the next morning. Gross necropsy and histologic findings were diagnostically inconclusive. Rumen contents tested positive for the alkaloid calycanthine, a centrally‐acting convulsant known to be present in wintersweet. Case reports of calycanthine toxicity in ruminants are limited, with no detailed reports published in the United States. Calycanthine has been isolated from the seeds, flowers, and leaves of the plant. Wintersweet is part of the family Calycanthaceae that including 3 species native to North America, all of which pose a neurologic risk to ruminants if consumed. [ABSTRACT FROM AUTHOR]

Here, we introduce the third release of Kalium database (http://kaliumdb.org/), a manually curated comprehensive depository that accumulates data on polypeptide ligands of potassium channels. The major goal of this amplitudinous update is to summarize findings for natural polypeptide ligands of K+ channels, as well as data for the artificial derivatives of these substances obtained over the decades of exploration. We manually analyzed more than 700 original manuscripts and systematized the information on mutagenesis, production of radio‐ and fluorescently labeled derivatives, and the molecular pharmacology of K+ channel ligands. As a result, data on more than 1200 substances were processed and added enriching the database content fivefold. We also included the electrophysiological data obtained on the understudied and neglected K+ channels including the heteromeric and concatenated channels. We associated target channels in Kalium with corresponding entries in the official database of the International Union of Basic and Clinical Pharmacology. Kalium was supplemented with an adaptive Statistics page, where users are able to obtain actual data output. Several other improvements were introduced, such as a color code to distinguish the range of ligand activity concentrations and advanced tools for filtration and sorting. Kalium is a fully open‐access database, crosslinked to other databases of interest. It can be utilized as a convenient resource containing ample up‐to‐date information about polypeptide ligands of K+ channels. [ABSTRACT FROM AUTHOR]

Domoic acid (DA), the causative agent of amnesic shellfish poisoning, is produced by select organisms within two distantly related algal clades: planktonic diatoms and red macroalgae. The biosynthetic pathway to isodomoic acid A was recently solved in the harmful algal bloom-forming diatom Pseudonitzschia multiseries, establishing the genetic basis for the global production of this potent neurotoxin. Herein, we sequenced the 507-Mb genome of Chondria armata, the red macroalgal seaweed from which DA was first isolated in the 1950s, identifying several copies of the red algal DA (rad) biosynthetic gene cluster. The rad genes are organized similarly to the diatom DA biosynthesis cluster in terms of gene synteny, including a cytochrome P450 (CYP450) enzyme critical to DA production that is notably absent in red algae that produce the simpler kainoid neurochemical, kainic acid. The biochemical characterization of the N-prenyltransferase (RadA) and kainoid synthase (RadC) enzymes support a slightly altered DA biosynthetic model in C. armata via the congener isodomoic acid B, with RadC behaving more like the homologous diatom enzyme despite higher amino acid similarity to red algal kainic acid synthesis enzymes. A phylogenetic analysis of the rad genes suggests unique origins for the red macroalgal and diatom genes in their respective hosts, with native eukaryotic CYP450 neofunctionalization combining with the horizontal gene transfer of N-prenyltransferases and kainoid synthases to establish DA production within the algal lineages.

Voltage-gated sodium channel NaV1.8 regulates transmission of pain signals to the brain. While NaV1.8 has the potential to serve as a drug target, the molecular mechanisms that shape NaV1.8 gating are not completely understood, particularly mechanisms that couple activation to inactivation. Interactions between toxin producing animals and their predators provide a novel approach for investigating NaV structure-function relationships. Arizona bark scorpions produce Na+ channel toxins that initiate pain signaling. However, in predatory grasshopper mice, toxins inhibit NaV1.8 currents and block pain signals. A screen of synthetic peptide toxins predicted from bark scorpion venom showed that peptide NaTx36 inhibited Na+ current recorded from a recombinant grasshopper mouse NaV1.8 channel (OtNaV1.8). Toxin NaTx36 hyperpolarized OtNaV1.8 activation, steady-state fast inactivation, and slow inactivation. Mutagenesis revealed that the first gating charge in the domain I (DI) S4 voltage sensor and an acidic amino acid (E) in the DII SS2 - S6 pore loop are critical for the inhibitory effects of NaTx36. Computational modeling showed that a DI S1 - S2 asparagine (N) stabilizes the NaTx36 - OtNaV1.8 complex while residues in the DI S3 - S4 linker and S4 voltage sensor form electrostatic interactions that allow a toxin glutamine (Q) to contact the first S4 gating charge. Surprisingly, the models predicted that NaTx36 contacts amino acids in the DII S5 - SS1 pore loop instead of the SS2 - S6 loop; the DII SS2 - S6 loop motif (QVSE) alters the conformation of the DII S5 - SS1 pore loop, enhancing allosteric interactions between toxin and the DII S5 - SS1 pore loop. Few toxins have been identified that modify NaV1.8 gating. Moreover, few toxins have been described that modify sodium channel gating via the DI S4 voltage sensor. Thus, NaTx36 and OtNaV1.8 provide tools for investigating the structure-activity relationship between channel activation and inactivation gating, and the connection to alternative pain phenotypes.

Sea anemones are well-spread everywhere in the World Ocean and represent the most ancient active poisonous organisms. Their main instrument of attack on other animals are the nematocysts – stinging organelles with the curtailed hollow thread with poisonous edge on the end. In order to attract their potential victims, they use fluorescent proteins. These proteins became a separate object of research as genetically coded markers for the observation of activity of promotors of genes. The poisonous secret of sea anemones is characterized by the presence of maximum number of peptides of various structural classes and spatial structures among the studied land and marine organisms (bees, spiders, scorpions, snakes ect.). This fact complicates the identification of sea anemones' secret and its differentiation from poisons of animals of other taxons, if the concrete source of its origin is unknown. The toxicity of some biologically active sea anemone peptides (RpI, RpIII) at intravenous administration to experimental animals is comparable with that of the most well-known and dangerous representatives of natural toxins with the similar mechanism of action (an alpha-hemolysine and tetrodotoxin), or chemical warfare agents, such as sarin and hydrogen cyanide. Based on their toxic effect, the biologically active sea anemone peptides generally can be classified as neurotoxins due to their impact on the functioning of sodium channels in the cells of the nervous system of animals. Cardiotoxic effect of sea anemone secret is caused by the specificity of interaction between its separate neurotoxins and one of the sub-types of sodium channels of muscle cells, characteristic for heart tissues. The main ways of identification of sea anemone neurotoxins in samples (for example, during the investigation of biological crimes) can be sequence by Edman`s method or tandem mass spectrometry (the analysis of fragments of toxin molecule for the establishment of its structure). Further study on the mechanisms of interaction between the sea anemone neurotoxins and the ion channels of the cells of nervous and muscular systems may result in the creation of medicines for treatment of channelopathy, as well as pluripotential antidotes, blocking the toxins, that influence on sodium channels.

[Display omitted] The gene structure and amino acid sequences of the precursor proteins of the sea anemone Heteractis magnifica neurotoxin RpII, a modulator of voltage-gated sodium channels, have been determined. A technology has been developed for the recombinant production of RpII in the Escherichia coli BL21(DE3) expression system based on the pET32b vector containing the thioredoxin gene, which opens up the possibility of obtaining a pure neurotoxin for further structural and/or pharmacological studies. The neurotoxin exhibits a neurotropic effect when administered intravenously to mice in doses greater than 1 mg kg−1, but is not lethal in doses up to 6 mg kg−1 and, in addition, RpII in the nm range does significantly increase the metabolism of human malignant glioblastoma U87-MG. [ABSTRACT FROM AUTHOR]

The larvae of some lampyrid beetles are highly specialized predators of snails. They have been observed to climb on the shells of their prey and use this exposed position to bite and inject secretions potentially originating from the midgut. Besides serving the purpose of extra-oral digestion (EOD), injected compounds also seem to have a paralyzing effect. Up to now, the toxins causing this paralyzing activity have not been identified. In the current study, we provide a first compositional analysis of the midgut secretion from lampyrid larvae, with a focus on identifying putative neurotoxins causing the observed paralyzing effect. For this purpose, we utilized a combined proteo-transcriptomic approach to characterize the compounds present in the midgut secretion of larval stages of Lampyris noctiluca. In terms of the absolute numbers of identified compounds, the midgut secretion is dominated by hydrolyzing enzymes comprising peptidases, carboxylesterases, and glycosidases. However, when considering expression levels, a few rather short cysteine-rich peptides exceed all other compounds. Some of these compounds show moderate similarity to putative neurotoxins identified in the venom of other arthropods and could be responsible for paralyzing effects. In addition to these potential toxins, we provide a list of peptides typical of the midgut secretion of L. noctiluca, supplemented by the corresponding precursor sequences.

The pathophysiology of Lyme disease, especially in its persistent form, remains to be determined. As many of the neurologic symptoms are similar to those seen in other toxin-associated disorders, a hypothesis was generated that B. burgdorferi, the causative agent of Lyme disease, may produce a neurotoxin to account for some of the symptoms. Using primers against known conserved bacterial toxin groups, and PCR technology, a candidate neurotoxin was discovered. The purified protein was temporarily named BbTox, and was subsequently found to be identical to BB0755, a protein deduced from the genome sequence of B. burgdorferi that has been annotated as a Z ribonuclease. BbTox has cytotoxic activity against cells of neural origin in tissue culture. Its toxic activity appears to be directed against cytoskeletal elements, similar to that seen with toxins of Clostridioides difficile and Clostridioides botulinum, but differing from that of cholera and E. coli toxins, and other toxins. It remains to be determined whether BbTox has direct cytotoxic effects on neural or glial cells in vivo, or its activity is primarily that of a ribonuclease analogous to other bacterial ribonucleases that are involved in antibiotic tolerance remains to be determined.

This retrospective, observational study describes the clinical findings, case management trends, and outcomes of 83 dogs and nine cats exposed to eastern coral snakes in a university teaching hospital setting. The medical records of dogs and cats that received antivenom following coral snake exposure were reviewed. Data collected included signalment, time to antivenom administration, physical and laboratory characteristics at presentation, clinical course during hospitalization, length of hospitalization, and survival to discharge. The mean time from presentation to coral snake antivenom administration was 2.26 ± 1.46 h. Excluding cases where the owner declined in-hospital care, the mean hospitalization time for dogs and cats was 50.8 h and 34 h, respectively. The mean number of antivenom vials was 1.29 (1–4). Gastrointestinal signs (vomiting and ptyalism) occurred in 42.2% (35/83) of dogs and 33.3% (3/9) of cats. Peripheral neurologic system deficits (ataxia, paresis to plegia, absent reflexes, and hypoventilation) were noted in 19.6% (18/92) of dogs and cats. Hemolysis was also common in 37.9% (25/66) of dogs but was not observed in cats. Mechanical ventilation (MV) was indicated in 12% (10/83) of dogs but no cats. Acute kidney injury (AKI), while rare, was a common cause of euthanasia at 20% (2/5) and was the most common complication during MV at 44.4% (4/9). Pigmenturia/hemolysis occurred in 88.9% (8/9) of MV cases and in all cases with AKI. Despite delays in antivenom administration by several hours, dogs and cats with coral snake exposure have low mortality rates (6% of dogs (5/83) and 0% of cats). Gastrointestinal signs were common but were not predictive of progression to neurological signs. Thus, differentiating between coral snake exposure and envenomation before the onset of neurological signs remains challenging.

Bacterial protein toxins are secreted by certain bacteria and are responsible for mild to severe diseases in humans and animals. They are among the most potent molecules known, which are active at very low concentrations. Bacterial protein toxins exhibit a wide diversity based on size, structure, and mode of action. Upon recognition of a cell surface receptor (protein, glycoprotein, and glycolipid), they are active either at the cell surface (signal transduction, membrane damage by pore formation, or hydrolysis of membrane compound(s)) or intracellularly. Various bacterial protein toxins have the ability to enter cells, most often using an endocytosis mechanism, and to deliver the effector domain into the cytosol, where it interacts with an intracellular target(s). According to the nature of the intracellular target(s) and type of modification, various cellular effects are induced (cell death, homeostasis modification, cytoskeleton alteration, blockade of exocytosis, etc.). The various modes of action of bacterial protein toxins are illustrated with representative examples. Insights in toxin evolution are discussed.

Abstract Background Parkinson's disease is a neurodegenerative disorder of the central nervous system that is one of the mental disorders that cause tremors, rigidity, and bradykinesia. Many factors determine the development of disease. A comprehensive physical examination and medical history of the patient should be part of the differential diagnosis for Parkinson’s disease (PD). According to epidemiology, Parkinson’s disease majorly affects elderly persons and frequency of affecting men is more as compared to women where the worldwide burden of Parkinson’s disease (PD) increased more than twice in the past 20 years. Main body of the abstract In this review paper, we discussed screening models, recent clinical trials, cellular and molecular pathways, and genetic variants (mutations) responsible for induction of Parkinson’s disease. The paper also aims to study the pathophysiology, epidemiology, general mechanism of action, risk factors, neurotoxin models, cellular and molecular pathway, clinical trials genetic variants of Parkinson’s disease. These models correspond to our research into the pathogenesis of Parkinson’s disease. The collected data for the review have been obtained by studying the combination of research and review papers from different databases such as PubMed, Elsevier, Web of Science, Medline, Science Direct, Medica Database, Elton B. Stephens Company (EBSCO), and Google open-access publications from the years 2017–2023, using search keywords such as “Cellular and molecular pathways, Clinical trials, Genetic mutation, Genetic models, Neurotoxin, Parkinson’s disease, Pathophysiology.” Short Conclusion Microglia and astrocytes can cause neuroinflammation, which can speed the course of pathogenic damage to substantia nigra (SN). The mechanism of Parkinson’s disease (PD) that causes tremors, rigidity, and bradykinesia is a decrease in striatal dopamine. Genes prominently CYP1A2 (Cytochrome P450 A2), GRIN2A, and SNCA are Parkinson’s disease (PD) hazard factor modifiers. The most well-known neurotoxin is 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), which destroys dopaminergic neurons, resulting in the development of Parkinson’s disease (PD). Dopamine auto-oxidation in dopaminergic (DA) neurons is a significant source of reactive oxygen species (ROS) that causes neuronal oxidative stress. Most common genes which when affected by mutation lead to development and progression of Parkinson’s disease (PD) are LRRK2, SNCA (alpha-synuclein protein), DJ-1, PRKN (Parkin protein), PINK1, GBA1, and VPS35. The commonly used neurotoxin models for inducing Parkinson's disease are 6-hydroxydopamine (6-OHDA), rotenone, paraquat, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), and genetic models. Anti-apoptic drugs, gene mutation therapy, cell-based therapy, and plasma therapy were all discontinued due to insufficient efficacy. Because it is unclear how aging affects these molecular pathways and cellular functions, future research into these pathways and their interactions with one another in healthy and diseased states is essential to creating disease-specific therapeutics.

Introduction: Neurotrophin-3 (NT3) is a neuroprotective growth factor that induces the development, maintenance and survival of neurons. This study aims to localize NT3-expressing cells in the adult zebrafish brain and examine the role of NT3 in a zebrafish Parkinson’s disease (PD) model.Methods: Cellular localization of NT3 in adult zebrafish brains was conducted using in situ hybridization. Subsequently, adult zebrafish were injected intraperitoneally with 100 μg/g of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and treated with 400 ng/g body weight of recombinant NT3 (rNT3) via intracranial injection 24 h following MPTP injection. The fish were assessed for neurobehavioral, gene expression, immunohistology, and protein analysis on days 3, 5 and 10 post-MPTP injection.Results: Our findings showed that NT3 was extensively expressed throughout the adult zebrafish brain in neurons. Administration of rNT3 has significantly improved locomotor activity, with upregulation of th1, dat, ntf3 and bdnf gene expressions compared to MPTP-induced zebrafish. Dopaminergic neurons were also significantly increased in the zebrafish brain following rNT3 treatment. ELISA analysis reported raised GST and decreased caspase-3 levels on day 3 of assessment. The trophic changes of rNT3, however, decline as the assessment day progresses.Conclusion: This study is the first to examine the role of NT3 in the adult zebrafish PD model. NT3 has remarkable trophic effects in the zebrafish PD model. However, further study is needed to examine the dosage requirements and long-term effects of NT3 in PD.

Scorpion α‐toxins (α‐NaTx) inhibiting the inactivation of voltage‐gated sodium channels (Nav) are a well‐studied family of small proteins. We previously showed that the structure of α‐NaTx specificity module responsible for selective Nav binding is governed by an interplay between the nest and niche protein motifs. Here, we report the solution structure of the toxin Lqq4 from the venom of the scorpion Leiurus quinquestriatus. Unexpectedly, we find that this toxin presents an ensemble of long‐lived structurally distinct states. We unequivocally assign these states to the alternative configurations (cis–trans isomers) of two peptide bonds: V56–P57 and C17–G18; neither of the cis isomers has been described in α‐NaTx so far. We argue that the native conformational space of α‐NaTx is wider than assumed previously. [ABSTRACT FROM AUTHOR]

Ion channels play a crucial role in diverse physiological processes, including neurotransmission and muscle contraction. Venomous creatures exploit the vital function of ion channels by producing toxins in their venoms that specifically target these ion channels to facilitate prey capture upon a bite or a sting. Envenoming can therefore lead to ion channel dysregulation, which for humans can result in severe medical complications that often necessitate interventions such as antivenom administration. Conversely, the discovery of highly potent and selective venom toxins with the capability of distinguishing between different isoforms and subtypes of ion channels has led to the development of beneficial therapeutics that are now in the clinic. This review encompasses the historical evolution of electrophysiology methodologies, highlighting their contributions to venom and antivenom research, including venom-based drug discovery and evaluation of antivenom efficacy. By discussing the applications and advancements in patch-clamp techniques, this review underscores the profound impact of electrophysiology in unravelling the intricate interplay between ion channels and venom toxins, ultimately leading to the development of drugs for envenoming and ion channel-related pathologies. [ABSTRACT FROM AUTHOR]

Snake venom research has historically focused on front-fanged species (Viperidae and Elapidae), limiting our knowledge of venom evolution in rear-fanged snakes across their ecologically diverse phylogeny. Three-finger toxins (3FTxs) are a known neurotoxic component in the venoms of some rear-fanged snakes (Colubridae: Colubrinae), but it is unclear how prevalent 3FTxs are both in expression within venom glands and more broadly among colubrine species. Here, we used a transcriptomic approach to characterize the venom expression profiles of four species of colubrine snakes from the Neotropics that were dominated by 3FTx expression (in the genera Chironius, Oxybelis, Rhinobothryum, and Spilotes). By reconstructing the gene trees of 3FTxs, we found evidence of putative novel heterodimers in the sequences of Chironius multiventris and Oxybelis aeneus, revealing an instance of parallel evolution of this structural change in 3FTxs among rear-fanged colubrine snakes. We also found positive selection at sites within structural loops or "fingers" of 3FTxs, indicating these areas may be key binding sites that interact with prey target molecules. Overall, our results highlight the importance of exploring the venoms of understudied species in reconstructing the full evolutionary history of toxins across the tree of life. [ABSTRACT FROM AUTHOR]

Envenomation by the Trinidad thick-tailed scorpion Tityus trinitatis may result in fatal myocarditis and there is a high incidence of acute pancreatitis among survivors. Peptidomic analysis (reversed-phase HPLC followed by MALDI-TOF mass spectrometry and automated Edman degradation) of T. trinitatis venom led to the isolation and characterization of three peptides with antimicrobial activity. Their primary structures were established asTtAP-1 (FLGSLFSIGSKLLPGVFKLFSRKKQ.NH2), TtAP-2 (IFGMIPGLIGGLISAFK.NH2) and TtAP-3 (FFSLIPSLIGGLVSAIK.NH2). In addition, potassium channel and sodium channel toxins, present in the venom in high abundance, were identified by CID-MS/MS sequence analysis. TtAP-1 was the most potent against a range of clinically relevant Gram-positive and Gram-negative aerobes and against the anaerobe Clostridioides difficile (MIC = 3.1–12.5 µg/mL). At a concentration of 1× MIC, TtAP-1 produced rapid cell death (<15 min against Acinetobacter baumannii and Staphylococcus aureus). The therapeutic potential of TtAP-1 as an anti-infective agent is limited by its high hemolytic activity (LC50 = 18 µg/mL against mouse erythrocytes) but the peptide constitutes a template for the design of analogs that maintain the high bactericidal activity against ESKAPE pathogens but are less toxic to human cells. It is suggested that the antimicrobial peptides in the scorpion venom facilitate the action of the neurotoxins by increasing the membrane permeability of cells from either prey or predator. [ABSTRACT FROM AUTHOR]

ABSTRACT To determine whether the neurotoxin BoNT/B2 causing botulism in Spain is clonal, the genetic diversity and phylogenetic relationships of Clostridium botulinum from food-borne episodes and infant cases of the condition were explored. The botulinum toxin gene (bont) subtype, the variable region of the flagellin gene (flaVR), and a seven-gene multi-locus sequence type were examined by sequencing 37 BoNT-positive cultures obtained over the period 2010 to 2022. Out of 37 botulism events, 16 food-borne episodes and 16 infant cases were associated with bont/b2. Eight bont/b2 alleles were detected [nucleotide distance range 0.0259–0.415%, Hunter and Gaston discrimination index (HGDI) 0.71]. The most common bont/b2 allele corresponded to that of strain Prevot 25 NCASE and its single and double locus variations (87.5%). Four known flaVR types were identified (HGDI 0.79), along with one previously unknown (flaVR-15). Sixteen sequence types (STs) (HGDI 0.89) were recorded including seven new STs (ST164–ST170; 10 new alleles) and five new STs (ST171–ST175; with new allele combinations) were also noted. Correlations among some STs and flaVR types were seen. Overall, the present results show that the combined analysis of bont/b2-flaVR-ST at the nucleotide level could be used to track botulism events in Spain. The neurotoxin BoNT/B2 has largely been responsible for human botulism in Spain. The polymorphism analysis of bont/b2, flaVR typing, and sequence type determinations, revealed a wide variety of clones to be responsible for human botulism, ruling out a common source of acquisition. IMPORTANCE Botulism, a potentially fatal disease, is classically characterized by a symmetrical descending flaccid paralysis, which if left untreated can lead to respiratory failure and death. Botulinum neurotoxin (BoNT), produced by certain species of Clostridium, is the most potent biological toxin known, and the direct cause of botulism. This study characterizes the acquisition in Spain of two forms of botulism, i.e., food-borne and infant botulism, which are largely caused by the main neurotoxin BoNT/B2. Polymorphism analysis of the bont/b2 gene, typing of the flagellin variable region sequence (flaVR), and multilocus sequence typing, were used to explore the genetic background of Clostridium botulinum group I. To our knowledge, this is the first phylogenetic and typing study of botulism undertaken in Spain.

Immunotherapy is a promising method for cancer treatment. Among them, immune checkpoint inhibitors targeting PD-1/PD-L1 are increasingly used for certain cancers. However, with the widespread use of such drugs, reports of immune-related adverse events (irAEs) are also increasing. Neurological adverse events (nAEs) are one of the irAEs that affect the peripheral and central nervous systems. They are characterized by low incidence, hard to diagnose, and lifethreatening risks, which have a significant impact on the prognosis of patients. Biomarker-based early diagnosis and subsequent treatment strategies are worthy of attention, and comprehensive management of irAEs is important for optimizing patients’ quality of life and long-term outcomes. In this review, we summarized the mechanisms, common symptoms, early biomarkers, treatments, and future research directions of nAEs, in order to provide a comprehensive overview of immune checkpoint inhibitor-related nAEs targeting PD-1/PD-L1. [ABSTRACT FROM AUTHOR]

Simple Summary: Botulinum neurotoxins have been considered for therapeutic effects in different animal species and for several conditions. However, a review of the reports and the identification of the research priorities in this field is still lacking. This study provides an overview of the current knowledge on the characteristics and the mechanism of action of the available botulinum neurotoxin formulations applied in veterinary medicine, identifying critical issues and research gaps. Overall, the literature largely supports the beneficial activity of such toxins to manage pain and to treat a variety of dystonias and highlights the need for additional research. Botulinum neurotoxins (BoNTs) are emerging as multipurpose therapeutic compounds for the treatment of several different syndromes involving peripheral and central nervous systems, and muscular and musculoskeletal disorders both in human and veterinary medicine. Therefore, the study of BoNTs is rapidly developing and identifying newly produced BoNT variants. Efforts should be made to clarify the biological and pharmacological characteristics of these novel BoNTs as well as the natural ones. The high potential of BoNTs as a therapeutic compound for medical syndromes lies in its ability to reach a specific cell type while bypassing other cells, thus having mild or no side effects. In this paper the recent developments in BoNTs are reviewed with the aim of analyzing the current knowledge on BoNTs' biological mechanisms of action, immunogenicity, formulations, and therapeutic applications in the veterinary field, highlighting advantages and drawbacks and identifying the gaps to be filled in order to address research priorities. [ABSTRACT FROM AUTHOR]

Tetrodotoxin (TTX) is a potent neurotoxin that was first identified in pufferfish but has since been isolated from an array of taxa that host TTX-producing bacteria. However, determining its origin, ecosystem roles, and biomedical applications has challenged researchers for decades. Recognized as a poison and for its lethal effects on humans when ingested, TTX is primarily a powerful sodium channel inhibitor that targets voltage-gated sodium channels, including six of the nine mammalian isoforms. Although lethal doses for humans range from 1.5-2.0 mg TTX (blood level 9 ng/mL), when it is administered at levels far below LD50, TTX exhibits therapeutic properties, especially to treat cancer-related pain, neuropathic pain, and visceral pain. Furthermore, TTX can potentially treat a variety of medical ailments, including heroin and cocaine withdrawal symptoms, spinal cord injuries, brain trauma, and some kinds of tumors. Here, we (i) describe the perplexing evolution and ecology of tetrodotoxin, (ii) review its mechanisms and modes of action, and (iii) offer an overview of the numerous ways it may be applied as a therapeutic. There is much to be explored in these three areas, and we offer ideas for future research that combine evolutionary biology with therapeutics. The TTX system holds great promise as a therapeutic and understanding the origin and chemical ecology of TTX as a poison will only improve its general benefit to humanity.