Emerging options for the management of scorpion stings

Proteomic analysis and lethality of the venom of Aegaeobuthus nigrocinctus, a scorpion of medical significance in the Middle East

The scorpion Aegaeobuthus nigrocinctus inhabits areas in Turkey and the Levant region of the Middle East where severe/lethal envenomings have been reported. Previous research indicated its extreme venom lethality to vertebrates and distinct envenomation syndrome. We report on the composition of A. nigrocinctus venom from Lebanese specimens using nESI-MS/MS, MALDI-TOF MS, SDS-PAGE and RP-HPLC. Venom lethality in mice was also assessed (LD50 = 1.05 (0.19-1.91) mg/kg, i.p), confirming A. nigrocinctus venom toxicity from Levantine populations. Forty-seven peaks were resolved using RP-HPLC, 25 of which eluted between 20 and 40 % acetonitrile. In reducing SDS-PAGE, most predominant components were <10 kDa, with minor components at higher molecular masses of 19.6, 26.1, 46.3 and 57.7 kDa. MALDI-TOF venom fingerprinting detected 20 components within the 1,000-12,000 m/z range. Whole venom 'shotgun' bottom-up nLC-MS/MS approach, combined with in-gel tryptic digestion of SDS-PAGE bands, identified at least 67 different components belonging to 15 venom families, with ion channel-active components (K+ toxins (23); Na+ toxins (20); Cl- toxins (2)) being predominant. The sequence of a peptide (named α-KTx9.13) ortholog to Leiurus hebraeus putative α-KTx9.3 toxin was fully determined, which exhibited 81-96 % identity to other members of the α-KTx9 subfamily targeting Kv1.x and Ca2+-activated K+ channels. Chlorotoxin-like peptides were also identified. Our study underscores the medical significance of A. nigrocinctus in the region and reveals the potential value of its venom components as lead templates for biomedical applications. Future work should address whether available antivenoms in the Middle East are effective against A. nigrocinctus envenoming in the Levant area.

Unlocking nature's arsenal: Nanotechnology for targeted delivery of venom toxins in cancer therapy

AIM

The aim of the present review is to shed light on the nanotechnological approaches adopted to overcome the shortcomings associated with the delivery of venom peptides which possess inherent anti-cancer properties.

BACKGROUND

Venom peptides although have been reported to demonstrate anti-cancer effects, they suffer from several disadvantages such as in vivo instability, off-target adverse effects, limited drug loading and low bioavailability. This review presents a comprehensive compilation of different classes of nanocarriers while underscoring their advantages, disadvantages and potential to carry such peptide molecules for in vivo delivery. It also discusses various nanotechnological aspects such as methods of fabrication, analytical tools to assess these nanoparticulate formulations, modulation of nanocarrier polymer properties to enhance loading capacity, stability and improve their suitability to carry toxic peptide drugs.

CONCLUSION

Nanotechnological approaches bear great potential in delivering venom peptide-based molecules as anticancer agents by enhancing their bioavailability, stability, efficacy as well as offering a spatiotemporal delivery approach. However, the challenges associated with toxicity and biocompatibility of nanocarriers must be duly addressed.

PERSPECTIVES

The everlasting quest for new breakthroughs for safer delivery of venom peptides in human subjects is fuelled by unmet clinical needs in the current landscape of chemotherapy. In addition, exhaustive efforts are required in obtaining and purifying the venom peptides followed by designing and optimizing scale up technologies.

Development and Efficacy of the Antivenom Specific to Severe Envenomations in Morocco and North Africa: Advancements in Scorpion Envenomation Management

Scorpion envenomation poses a global public health issue, with an estimated 1,500,000 cases worldwide annually resulting in 2600 deaths. North Africa, particularly Morocco, experiences severe envenomations, mainly attributed to Androctonus mauretanicus and Buthus occitanus in Morocco, and Buthus occitanus and Androctonus australis hector in Algeria and Tunisia, with case numbers often underestimated. Current treatment relies mainly on symptomatic approaches, except in Morocco, where management is limited to symptomatic treatment due to controversies regarding specific treatment. In Morocco, between 30,000 and 50,000 scorpion envenomation cases are reported annually, leading to hundreds of deaths, mainly among children. Controversies among clinicians persist regarding the appropriate course of action, often limiting treatments to symptomatic measures. The absence of a specific antivenom for the venoms of the most lethal scorpions further exacerbates the situation. This study aims to address this gap by developing a monovalent antivenom against the endemic and most dangerous scorpion, Androctonus mauretanicus. The antivenom was produced by immunizing albino rabbits with a mixture of Androctonus mauretanicus venom collected from high-risk areas in Morocco. Immunizations were performed by subcutaneous injections at multiple sites near the lymphatic system, following an immunization schedule. Production control of neutralizing antibody titers was conducted through immunodiffusion. Once a sufficient antibody titer was achieved, blood collection was performed, and the recovered plasma underwent affinity chromatography. The efficacy of purified IgG was evaluated by determining the ED50 in mice, complemented by histological and immunohistochemical studies on its ability to neutralize venom-induced tissue alterations and the neutralization of toxins bound to receptors in the studied organs. The monovalent antivenom demonstrated specificity against Androctonus mauretanicus venom and effective cross-protection against the venom of the scorpions Buthus occitanus and Androctonus australis hector, highly implicated in lethal envenomations in the Maghreb. This study shows that the developed monovalent antivenom exhibits notable efficacy against local scorpions and a surprising ability to neutralize the most lethal envenomations in North Africa. These results pave the way for a new, more specific, and promising therapeutic approach to countering severe scorpion envenomations, especially in Morocco, where specific treatment is lacking.

Divergence in toxin antigenicity and venom enzymes in Tityus melici, a medically important scorpion, despite transcriptomic and phylogenetic affinities with problematic Brazilian species

The Brazilian scorpion Tityus melici, native to Minas Gerais and Bahia, is morphologically related to Tityus serrulatus, the most medically significant species in Brazil. Despite inhabiting scorpion-envenomation endemic regions, T. melici venom remains unexplored. This work evaluates T. melici venom composition and function using transcriptomics, enzymatic activities, and in vivo and in vitro immunological analyses. Next-Generation Sequencing unveiled 86 components putatively involved in venom toxicity: 39 toxins, 28 metalloproteases, seven disulfide isomerases, six hyaluronidases, three phospholipases and three amidating enzymes. T. serrulatus showed the highest number of toxin matches with 80-100 % sequence similarity. T. melici is of medical importance as it has a venom LD50 of 0.85 mg/kg in mice. We demonstrated venom phospholipase A2 activity, and elevated hyaluronidase and metalloprotease activities compared to T. serrulatus, paralleling our transcriptomic findings. Comparison of transcriptional levels for T. serrulatus and T. melici venom metalloenzymes suggests species-specific expression patterns in Tityus. Despite close phylogenetic association with T. serrulatus inferred from COI sequences and toxin similarities, partial neutralization of T. melici venom toxicity was achieved when using the anti-T. serrulatus antivenom, implying antigenic divergence among their toxins. We suggest that the Brazilian therapeutic scorpion antivenom could be improved to effectively neutralize T. melici venom.

Evaluation of Scorpion Stings in Children

INTRODUCTION

Scorpion stings are a significant public health problem in many parts of the world. Children are at a higher risk of developing severe complications from scorpion envenoming, including cardiac, respiratory, and neurologic complications. In Turkey, members of the Buthidae family are the most common culprits in severe envenoming events.

METHODS

This retrospective-descriptive study was conducted in Turkey. Children aged 0 to 18 y admitted to the emergency department of Kahta State Hospital between December 2017 and December 2020 were included in the study. Patient information was reviewed, and 78 patients with complete demographic, laboratory, and clinical data were included in the study.

RESULTS

Out of the 78 patients, 24.4% were six years old or younger while the 75.6% were older than six years. Alpha blocker was given to 12.8% of the patients, and antivenom was given to 43.6% of the patients. Of the 78 patients, 71.8% were followed up in the emergency department, 21.8% were followed up in the inpatient unit, and 6.4% were followed up in the intensive care unit. Two patients (2.6%) died within 1 month. There was a significant difference regarding lactate dehydrogenase value according to the sting site (P=0.014). Lactate dehydrogenase values of patients stung on the head and neck and upper extremity were higher than those of patients bitten on lower extremities.

CONCLUSIONS

Elevated levels of specific laboratory parameters, such as leukocytes, aspartate transaminase, and lactate dehydrogenase, are linked to worse outcomes. Additionally, stings on the head, neck, and upper extremities are more strongly associated with severity. These findings guide tailored treatment strategies for scorpion stings, with the potential for further refinement through broader studies across diverse regions and populations.

Neutralization Capacity of Tissue Alterations Caused by the Venoms of the Most Dangerous Scorpions in North Africa Using a Selective Antivenom

In North Africa, scorpion stings pose an urgent public health problem, particularly for children with high morbidity and mortality rates. The main species implicated are the Androctonus mauretanicus (Am), Androctonus australis hector (Aah), and Buthus occitanus (Bo). Immunotherapy is the specific therapeutic approach aimed at directly neutralizing toxins, despite their severity and rapid diffusion. In the present study, we evaluate, histologically and immunohistologically, the neutralization potency of the selective antivenom produced against, among other species, the Am, Aah, and Bo at the level of the tissue alterations in Swiss mice, as experimental subjects. Firstly, the lethal doses 50 test was conducted to assess the venom's toxic activity, and then the median effective dose of the antivenom was determined against each venom. The histological and immunohistological analyses were performed by injecting the sublethal dose of venom, the complex venom and antivenom, or the antivenom 2 h following inoculation of venom. Our study revealed the highest toxicity of the Am, followed by the Aah and then the Bo venom. The neutralizing ability and effectiveness of the antivenom to completely or partially neutralize the tissular damages were demonstrated in all organs studied: brain, heart, lungs, liver, and kidneys. Our results highlighted the important cytoplasmic and membranous staining in the heart compared to the brain tissue for the three scorpion venoms. Therefore, the scorpionic antivenoms are able to reach their target even at the tissue level. Immunotherapy represents the specific and recommended treatment against the scorpionic stings in North Africa.

Scorpion Stings in Minas Gerais (Brazil): A Monocentric Retrospective Study Evaluating All Envenoming Cases of Local Scorpionism

INTRODUCTION

We aim to provide better insights into the demographic, epidemiological, and seasonal characteristics of scorpion envenomation reported in the Rio Doce Valley, Brazil.

METHODS

We conducted this monocentric retrospective descriptive study with data on Investigation Forms of Accidents by Venomous Animals, only envenoming cases of scorpion stings, between January 1, 2017 and December 31, 2020, belonging to the compulsory notification system of the Municipal Hospital of Governador Valadares.

RESULTS

There were 3032 accidents, and the male-to-female ratio was 1.17:1 (male, 54%; females, 46%). Accidents occurred every month, but there was an increase in June, July, and October to January. In most cases, the time between the scorpion sting and medical care was between 1 and 3 h (n=1304; 43%). The most frequent clinical and systemic manifestations were pain at the bite site (94%) and vagal symptoms (7%). Cases were mild (n=2750, 91%), moderate (n=221, 7%), and severe (n=56, 2%). Children younger than 10 y constituted the most cases, 522 (17%). There was a significant difference between clinical severity and age (P<0.01). Ten patients developed acute pulmonary edema. Two 4-y-old children died. All severely envenomated patients as well as 74% and 2% of mild and moderately envenomated patients, respectively, received specific scorpion antivenoms.

CONCLUSIONS

Scorpion envenomation is of greater severity in children aged <10 y. The clinical presentation includes mainly local pain associated with vagal symptoms. Accidents occur every month, but there was an increase in June, July, and October to January.

Scorpion venom peptides: Molecular diversity, structural characteristics, and therapeutic use from channelopathies to viral infections and cancers

Animal venom is an important evolutionary innovation in nature. As one of the most representative animal venoms, scorpion venom contains an extremely diverse set of bioactive peptides. Scorpion venom peptides not only are 'poisons' that immobilize, paralyze, kill, or dissolve preys but also become important candidates for drug development and design. Here, the review focuses on the molecular diversity of scorpion venom peptides, their typical structural characteristics, and their multiple therapeutic or pharmaceutical applications in channelopathies, viral infections and cancers. Especially, the group of scorpion toxin TRPTx targeting transient receptor potential (TRP) channels is systematically summarized and worthy of attention because TRP channels play a crucial role in the regulation of homeostasis and the occurrence of diseases in human. We also further establish the potential relationship between the molecular characteristics and functional applications of scorpion venom peptides to provide a research basis for modern drug development and clinical utilization of scorpion venom resources.

A Fast Method for Detection of Fake Venoms and Investigation of Interspecies Variation Using Venoms of Androctonus, Buthus, and Leiurus (Scorpiones: Buthidae) Species

Background

Within the scorpion family Buthidae, some of the most dangerous venomous genera are Androctonus (A), Buthus (B), and Leiurus (L). This venom is valuable raw material for numerous therapeutic formulations because of its pharmacological potential; however, because of its high prices in the global market, fake "venom mixes" are being made to market illegally, and it is important that these unknown mixes be evaluated. A fast and accurate response to the request for this identification is necessary.

Method

This study was conducted in Turkey in 2022. Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) is a linear positive-ionization mode was used for identification of scorpion species. The mass spectra of the three scorpion venoms were examined in detail. The peptide and protein profiles in the venoms of congenerous three scorpion venoms and the proportional differences in these venoms were investigated. For interspecific variation, a principal component analysis of all venoms was conducted, and variance values and distance-proximity indices were determined.

Results

The top three peptide masses in the highest relative abundance for A. australis, B. mardochei, and L. quinquestriatus quinquestriatus, respectively, were 6901, 7431, and 7447; 4238, 5283, and 4055; and 3828, 7868, and 6799 Da. While the variance rate between A. australis and the other two venoms was 40%, this rate was 38% between B. mordochei and L. quinquestriatus quinquestriatus venoms.

Conclusion

A very simple protocol of species identification using scorpion venom samples was created using recent advances in MALDI-TOF MS.

Production of recombinant scorpion antivenoms in E. coli: current state and perspectives

Scorpion envenomation is a serious health problem in tropical and subtropical zones. The access to scorpion antivenom is sometimes limited in availability and specificity. The classical production process is cumbersome, from the hyper-immunization of the horses to the IgG digestion and purification of the F(ab)'₂ antibody fragments. The production of recombinant antibody fragments in Escherichia coli is a popular trend due to the ability of this microbial host to produce correctly folded proteins. Small recombinant antibody fragments, such as single-chain variable fragments (scFv) and nanobodies (V_HH), have been constructed to recognize and neutralize the neurotoxins responsible for the envenomation symptoms in humans. They are the focus of interest of the most recent studies and are proposed as potentially new generation of pharmaceuticals for their use in immunotherapy against scorpion stings of the Buthidae family. This literature review comprises the current status on the scorpion antivenom market and the analyses of cross-reactivity of commercial scorpion anti-serum against non-specific scorpion venoms. Recent studies on the production of new recombinant scFv and nanobodies will be presented, with a focus on the Androctonus and Centruroides scorpion species. Protein engineering-based technology could be the key to obtaining the next generation of therapeutics capable of neutralizing and cross-reacting against several types of scorpion venoms. KEY POINTS: • Commercial antivenoms consist of predominantly purified equine F(ab)'₂fragments. • Nanobody-based antivenom can neutralize Androctonus venoms and have a low immunogenicity. • Affinity maturation and directed evolution are used to obtain potent scFv families against Centruroides scorpions.

Comparative Proteomic Analysis of the Venoms from the Most Dangerous Scorpions in Morocco: Androctonus mauritanicus and Buthus occitanus

Morocco is known to harbor two of the world's most dangerous scorpion species: the black Androctonus mauritanicus (Am) and the yellow Buthus occitanus (Bo), responsible for 83% and 14% of severe envenomation cases, respectively. Scorpion venom is a mixture of biological molecules of variable structures and activities, most of which are proteins of low molecular weights referred to as toxins. In addition to toxins, scorpion venoms also contain biogenic amines, polyamines, and enzymes. With the aim of investigating the composition of the Am and Bo venoms, we conducted an analysis of the venoms by mass spectrometry (ESI-MS) after separation by reversed-phase HPLC chromatography. Results from a total of 19 fractions obtained for the Am venom versus 22 fractions for the Bo venom allowed the identification of approximately 410 and 252 molecular masses, respectively. In both venoms, the most abundant toxins were found to range between 2-5 kDa and 6-8 kDa. This proteomic analysis not only allowed the drawing of an extensive mass fingerprint of the Androctonus mauritanicus and Buthus occitanus venoms but also provided a better insight into the nature of their toxins.

Ethnomedicines for the treatment of scorpion stings: A perspective study

ETHNOPHARMACOLOGICAL RELEVANCE

Scorpion sting is a public health concern with limited clinical symptomatic treatment. The clinical treatment uses anti-scorpion antivenom and prazosin (α-adrenergic inhibitor), often in combination with insulin, to reduce scorpion venom-induced hyperglycemia and other complications. However, these therapies also possess some limitations, necessitating urgent exploration of ethnomedicines, mainly traditional medicinal plants, to treat scorpion stings. Unfortunately, several conventional treatments are not scientifically validated, thus raising questions about their quality and utility. Therefore, pharmacological re-assessment of such medicinal plants to alleviate scorpion stings' complications is essential.

AIM OF THE STUDY

The principal objectives of this study are to provide a brief overview of medically important scorpions of the world, outline the extant traditional practices, and comprehensively review plants used in conventional ethnic medicines to treat scorpion stings over time. Modern technological advances in identifying and characterizing plant bioactive molecules are also mentioned in this review.

MATERIALS AND METHODS

The traditionally used medicinal plants against scorpion stings were reviewed from the available literature in the database. The Plant List (http://www.theplantlist.org/) was used to validate the scientific names of the plants mentioned in this study. The search targeted literature on conventional treatments and crude plant extracts or their bioactive components with proven neutralization capacity against scorpion stings. Search words used were 'scorpion sting,' 'treatment for a scorpion sting,' 'antivenom and scorpion sting,' 'traditional treatment for scorpion stings, and 'natural compounds against scorpion stings'.

RESULTS

A list of more than 200 medicinal plants traditionally used in several countries for treating scorpion stings is presented in this review. Though some myth-based remedies are practiced to treat scorpion stings, no empirical evidence exists to validate this aspect of traditional knowledge. Only 38 traditional medicinal plant extracts have been tested under in-vivo and in-vitro conditions to determine their neutralization potency of scorpion envenomation. Although a few bioactive plant constituents showing scorpion venom neutralization potency have been characterized, they are not yet commercially available for clinical application.

CONCLUSIONS

There is tremendous potential locked in medicinal plants' traditional knowledge for scorpion envenomation treatment. Translating this knowledge into the clinical application will require pharmacological reassessment, in tandem with isolation and characterization of active compounds to prove their prophylactic prowess. Almost equally important would be the formulation of stringent strategies to conserve such medicinal plants from overexploitation.

Case Report: Fatal Scorpion Envenomation in a Shuar Child by Tityus cisandinus from Amazonian Ecuador: A Call for Specific Antivenom Availability in the Amazon Basin

Envenomation by scorpions belonging to the genus Tityus can be life threatening in the Americas, particularly in the Amazon Basin. We report a 4-month-old Ecuadorean boy of Shuar origin stung by a scorpion identified as Tityus cisandinus in the Amazonian province of Morona Santiago, presenting with pulmonary edema and systemic inflammation. We administered immunotherapy using the scorpion antivenom available in Ecuador, of Mexican origin (anti-Centruroides). Catecholamine discharge-related events such as hyperglycemia and thrombocytosis were resolved after treatment but leukocytosis did not, suggesting that factors associated with the sting-admission delay and specificity of antivenom played a role in the envenomation outcome. Cardiorespiratory arrest determined a fatal outcome, despite specific maneuvers. The case severity and the limited supply of nonspecific scorpion antivenoms in problematic areas of Amazonian Ecuador and elsewhere in northwestern Amazonia are discussed in regard to the need for specific therapeutic immunoglobulins in the area and in the Amazon Basin as a whole.

Clinical, epidemiological and faunistic characterization of scorpionism in Azilal, Central High Atlas (Morocco)

The province of Azilal is one of the most scorpion-infested areas in Morocco. The current study aims to investigate the clinical and epidemiological characteristics of scorpion envenomation in the Azilal province, as well as to contribute to the study of its scorpio-faunistic diversity. We examined clinical and epidemiological data from 5684 scorpion stings recorded between 2017 and 2021. Prospections on the ground were carried out in the study area. The species were identified using the taxonomic keys. Distribution maps of inventoried species have been created using SIG. 5684 scorpions stings were reported in the study area, with 18 cases of deaths. Most of the cases was reported in the summer especially at night (64%). A positive significant correlation was found between scorpion stings incidence and season (P < 0.005; r = 0.56). A positive correlation was found between scorpion stings incidence and mortality (r = 0.09). Pediatric mortality was higher compared to lethality in adults (P < 0.05). A positive correlation was found between the number of stung children (Age <15 years) and the number of patients presenting clinical signs of severe envenomation (Class III) (r = 0.40). The percentage of patients that use traditional remedies was significantly higher in the rural areas (P < 0.05). Most scorpion stings occurred in human habitat (54.5%) or in their neighbourhood (24.5%). Six species were identified in the study area. The findings of this study have highlighted the extent of scorpion envenomation and have elucidated certain characteristics of the scorpio-faunistic biodiversity in the Azilal province.

Scorpion Peptides and Ion Channels: An Insightful Review of Mechanisms and Drug Development

The Buthidae family of scorpions consists of arthropods with significant medical relevance, as their venom contains a diverse range of biomolecules, including neurotoxins that selectively target ion channels in cell membranes. These ion channels play a crucial role in regulating physiological processes, and any disturbance in their activity can result in channelopathies, which can lead to various diseases such as autoimmune, cardiovascular, immunological, neurological, and neoplastic conditions. Given the importance of ion channels, scorpion peptides represent a valuable resource for developing drugs with targeted specificity for these channels. This review provides a comprehensive overview of the structure and classification of ion channels, the action of scorpion toxins on these channels, and potential avenues for future research. Overall, this review highlights the significance of scorpion venom as a promising source for discovering novel drugs with therapeutic potential for treating channelopathies.

Peptides with Diverse Functions from Scorpion Venom: A Great Opportunity for the Treatment of a Wide Variety of Diseases

Toxicology Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran

The venom glands are a rich source of biologically important peptides with pharmaceutical properties. Scorpion venoms have been identified as a reservoir for components that might be considered as great candidates for drug development. Pharmacological properties of the venom compounds have been confirmed in the treatment of different disorders. Ion channel blockers and AMPs are the main groups of scorpion venom components. Despite the existence of several studies about scorpion peptides, there are still valuable components to be discovered. Additionally, owing to the improvement of proteomics and transcriptomics, the number of peptide drugs is steadily increasing, which reflects the importance of these medications. This review evaluates available literatures on some important scorpion venom peptides with pharmaceutical activities. Given that the last three years have been dominated by the COVID-19 from the medical/pharmaceutical perspective, scorpion compounds with the potential against the coronavirus 2 (SARS-CoV-2) are discussed in this review.

Spatial Analysis in Areas with High Occurrence of Accidents Caused by Tityus serrulatus and Tityus bahiensis (Scorpiones: Buthidae) in Brazil

INTRODUCTION

In Brazil, scorpion stings are recorded in high numbers with an increasing epidemiological situation in most municipalities. In the present study, data between 1998 and 2018 in Americana, São Paulo, were analyzed.

METHODS

In total, 4122 records on scorpion stings were georeferenced using a Garmin eTREX 30X global positioning system device, with WGS84 datum projection and Universal Transverse Mercator zone 23S. Multiple Poisson regression was used to explore the relationship between the incidence rates of stings and urban planning areas (UPAs). Eight quantitative variables were used to establish the environmental and anthropic characterization of UPAs associated or not associated with scorpionism. A spatial analysis was performed for geoprocessing maps of Americana using spatial statistics tools (optimized hotspot analysis and kernel density function) from cartographic clusters in the ArcMap software, version 10.5.

RESULTS

The optimized hotspot analysis tool identified spatial clusters with high values of the incidence of scorpion stings in the surroundings of all UPAs in the municipality. The estimation of the kernel function of event intensity showed a wide distribution of stings across the area of the entire municipal territory, with UPA-02 and UPA-06 exhibiting the highest occurrence of scorpion stings. Six significant hotspots were established as highest-event-density areas (with occurrences of 160-270) and were contiguous to 4 environmental protection areas, located in more peripheral regions, and to 2 municipal cemeteries, which were located in urban central areas.

CONCLUSIONS

This analysis showed that the risk of scorpion stings in different Americana's UPAs has increased occurrence and incidence intensity.

An overview of Tityus cisandinus scorpion venom: Transcriptome and mass fingerprinting reveal conserved toxin homologs across the Amazon region and novel lipolytic components

Tityus cisandinus, a neglected medically important scorpion in Ecuadorian and Peruvian Amazonia, belongs to a complex of species related to the eastern Amazon endemic Tityus obscurus, spanning a distribution of ca. 4000 km. Despite high morbidity and mortality rates, no effective scorpion antivenom is currently available in the Amazon region. Knowledge of the structural/functional relationships between T. cisandinus venom components and those from related Amazonian species is crucial for designing region-specific therapeutic antivenoms. In this work, we carried out the first venom gland transcriptomic study of an Amazonian scorpion outside Brazil, T. cisandinus. We also fingerprinted its total venom through MALDI-TOF MS, which supported our transcriptomic findings. We identified and calculated the expression level of 94 components: 60 toxins, 25 metalloproteases, five disulfide isomerases, three amidating enzymes, one hyaluronidase, and also uncovered transcripts encoding novel lipolytic beta subunits produced by New World buthid scorpions. This study demonstrates the high similarity between T. cisandinus and T. obscurus venoms, reinforcing the existence of a neglected complex of genetically and toxinologically related Amazonian scorpions of medical importance. Finally, we demonstrated the low recognition of currently available therapeutic sera against T. cisandinus and T. obscurus venoms, and concluded that these should be improved to protect against envenomation by Amazonian Tityus spp.

Do Spiders Ride on the Fear of Scorpions? A Cross-Cultural Eye Tracking Study

Deep fear of spiders is common in many countries, yet its origin remains unexplained. In this study, we tested a hypothesis based on recent studies suggesting that fear of spiders might stem from a generalized fear of chelicerates or fear of scorpions. To this end, we conducted an eye tracking experiment using a spontaneous gaze preference paradigm, with spiders and scorpions (previously neglected but crucial stimuli) as threatening stimuli and grasshoppers as control stimuli. In total, 67 participants from Somaliland and 67 participants from the Czech Republic were recruited and presented with a sequence of paired images. Both Somali and Czech people looked longer (total duration of the gaze) and more often (number of fixations) on the threatening stimuli (spiders and scorpions) when presented with a control (grasshopper). When both threatening stimuli were presented together, Somali participants focused significantly more on the scorpion, whereas in Czech participants, the effect was less pronounced, and in Czech women it was not significant. This supports the hypothesis that fear of spiders originated as a generalized fear of scorpions. Moreover, the importance of spiders as fear-eliciting stimuli may be enhanced in the absence of scorpions in the environment.

Scorpion Sting: A Hurt to the Heart Reported in a Tertiary Care Hospital in Central Rural India

Scorpion stings are painful but harmless and are rarely life-threatening. There is emerging evidence of the association of electrocardiographic (ECG) changes in patients following scorpion stings. We report a case of scorpion sting in a patient in central rural India and provide a review of similar published cases. A 55-year-old previously healthy female was hospitalized in the department of medicine at our institute within two hours of a scorpion sting. She presented with severe pain at the site of the sting and profuse sweating. Her routine investigations (complete blood count renal function test, liver function tests, and arterial blood gas analysis) results were normal. Her electrocardiogram revealed acute myocardial infarction, and serial ECG showed ST and T-wave changes. On laboratory investigation, it was found that her troponin-T was positive and creatinine phosphokinase levels were raised. There was apical wall hypokinesia on transthoracic echocardiography on Day 1 and Day 2. The patient recovered completely and was discharged within five days of hospitalization once her symptoms improved. This case highlights the severe presentation of scorpion stings in otherwise healthy females. The chances of improved clinical symptoms are more if prazosin (125-250 ug) is administered early after scorpion-stung patients experience cardiac abnormalities. This treatment can dramatically alter scorpion envenomation's morbidity and mortality depending on the duration after which it is administered. This case raised our interest due to cardiovascular manifestations in the patient and the early treatment with prazosin for the scorpion sting. Hence, this case was reported for the purpose of creating awareness among physicians and protecting the more vulnerable population.

Comparison of Intravenous Paracetamol, Dexketoprofen Trometamol, or Topical Lidocaine Use for Pain Relief in Scorpion Stings: A Placebo-Controlled, Randomized Study

INTRODUCTION

After a scorpion sting, patients commonly present to hospitals with pain. Our study sought to compare the analgesic efficacy of IV paracetamol, IV dexketoprofen trometamol, topical lidocaine, and placebo in patients reporting pain after presenting with a history of scorpion sting.

METHODS

This double-blind, randomized, placebo-controlled study was conducted in the emergency department of a tertiary hospital. Adult patients who presented with the complaint of pain after a scorpion sting and did not have systemic findings were randomly assigned to 1 of the following 4 groups: IV paracetamol, IV dexketoprofen trometamol, topical lidocaine, and placebo. The visual analog scale scores were measured at the time of presentation to the emergency department and at 30 and 60 min to determine the pain intensity.

RESULTS

The study included 106 patients, of whom 30 were in the paracetamol group, 26 in the dexketoprofen trometamol group, 25 in the topical lidocaine group, and 25 in the placebo group. We did not find a different analgesic effect among the groups in the first 30 min (P=0.185). IV paracetamol, dexketoprofen trometamol, and topical lidocaine did not show different analgesic effects in the first 60 min (P>0.05). IV paracetamol and dexketoprofen trometamol were found to provide a more effective analgesia than the placebo at 60 min (P<0.05). The analgesic effects of topical lidocaine and placebo did not differ (P=0.330).

CONCLUSIONS

IV paracetamol and IV dexketoprofen trometamol provided analgesia in the first 60 min, similar to topical lidocaine but superior to placebo.

French Scorpionism (Mainland and Oversea Territories): Narrative Review of Scorpion Species, Scorpion Venom, and Envenoming Management

Sixty-seven scorpion species have been described in France and its territories, where they have been found to be heterogeneously distributed. Indeed, only one species can be found on Réunion Island, while 38 species exist in French Guiana. The number of stings is also heterogenous, with up to 90 stings per 100,000 inhabitants occurring annually. Scorpion species can frequently be determined through simple visual factors, including species of medical importance (i.e., Buthus, Centruroides and Tityus). Scorpion venom is composed of local enzymes and peptides with a cysteine-stabilized α/β motif (NaTxs, Ktxs, Calcines), which allow for venom diffusion and the prey's incapacitation, respectively. Harmful scorpion species are limited to Centruroides pococki in the French West Indies, which can induce severe envenoming, and the Tityus obscurus and Tityus silvestris in French Guiana, which can cause fatalities in children and can induce severe envenoming, respectively. Envenomation by one of these scorpions requires hospital monitoring as long as systemic symptoms persist. Typical management includes the use of a lidocaine patch, pain killers, and local antiseptic. In the case of heart failure, the use of dobutamine can improve survival, and pregnant women must consult an obstetrician because of the elevated risk of preterm birth or stillbirth. France does not have scorpion antivenom, as scorpion stings are generally not fatal.

Acute Pancreatitis: Diagnosis and Treatment

Acute pancreatitis is a common indication for hospital admission, increasing in incidence, including in children, pregnancy and the elderly. Moderately severe acute pancreatitis with fluid and/or necrotic collections causes substantial morbidity, and severe disease with persistent organ failure causes significant mortality. The diagnosis requires two of upper abdominal pain, amylase/lipase ≥ 3 ×upper limit of normal, and/or cross-sectional imaging findings. Gallstones and ethanol predominate while hypertriglyceridaemia and drugs are notable among many causes. Serum triglycerides, full blood count, renal and liver function tests, glucose, calcium, transabdominal ultrasound, and chest imaging are indicated, with abdominal cross-sectional imaging if there is diagnostic uncertainty. Subsequent imaging is undertaken to detect complications, for example, if C-reactive protein exceeds 150 mg/L, or rarer aetiologies. Pancreatic intracellular calcium overload, mitochondrial impairment, and inflammatory responses are critical in pathogenesis, targeted in current treatment trials, which are crucially important as there is no internationally licenced drug to treat acute pancreatitis and prevent complications. Initial priorities are intravenous fluid resuscitation, analgesia, and enteral nutrition, and when necessary, critical care and organ support, parenteral nutrition, antibiotics, pancreatic exocrine and endocrine replacement therapy; all may have adverse effects. Patients with local complications should be referred to specialist tertiary centres to guide further management, which may include drainage and/or necrosectomy. The impact of acute pancreatitis can be devastating, so prevention or reduction of the risk of recurrence and progression to chronic pancreatitis with an increased risk of pancreas cancer requires proactive management that should be long term for some patients.

Neutralizing Dromedary-Derived Nanobodies Against BotI-Like Toxin From the Most Hazardous Scorpion Venom in the Middle East and North Africa Region

Scorpion envenoming is a severe health problem in many regions causing significant clinical toxic effects and fatalities. In the Middle East/North Africa (MENA) region, Buthidae scorpion stings are responsible for devastating toxic outcomes in human. The only available specific immunotherapeutic treatment is based on IgG fragments of animal origin. To overcome the limitations of classical immunotherapy, we have demonstrated the in vivo efficacy of NbF12-10 bispecific nanobody at preclinical level. Nanobodies were developed against BotI analogues belonging to a distinct structural and antigenic group of scorpion toxins, occurring in the MENA region. From Buthus occitanus tunetanus venom, BotI-like toxin was purified. The 41 N-terminal amino acid residues were sequenced, and the LD₅₀ was estimated at 40 ng/mouse. The BotI-like toxin was used for dromedary immunization. An immune VHH library was constructed, and after screening, two nanobodies were selected with nanomolar and sub-nanomolar affinity and recognizing an overlapping epitope. NbBotI-01 was able to neutralize 50% of the lethal effect of 13 LD₅₀ BotI-like toxins in mice when injected by i.c.v route, whereas NbBotI-17 neutralized 50% of the lethal effect of 7 LD₅₀. Interestingly, NbBotI-01 completely reduced the lethal effect of the 2 LD₅₀ of BotG50 when injected at 1:4 molar ratio excess. More interestingly, an equimolar mixture of NbBotI-01 with NbF12-10 neutralized completely the lethal effect of 7 and 5 LD₅₀ of BotG50 or AahG50, at 1:4 and 1:2 molar ratio, respectively. Hence, NbBotI-01 and NbF12-10 display synergic effects, leading to a novel therapeutic candidate for treating Buthus occitanus scorpion stings in the MENA region.

Güneybatı Türkiye'de Çocuklarda Akrep Sokması: Bir Eğitim ve Araştırma Hastanesi Deneyimi

Aim: The aim of this study is to evaluate the clinical and laboratory features and prognosis of scorpion stings in children. Methods: This retrospective study was in children with scorpion stings who were admitted to the pediatric emergency department in Alanya Alaaddin Keykubat University (ALKU) Training and Research Hospital between 1st of January 2019-31 st of December 2020. Demographic data, admission date, time intervals from sting to admission to hospital, geographical location in which the sting occurred, affected body sites, local and systemic signs and symptoms of envenomation, results of hematological and biochemical laboratory tests, management, length of hospital stay, and outcome were recorded. Results: Totally, medical records of 111 children were reviewed. Patients were divided according to the clinical findings into 3 groups, 70 patients (63.1%) with mild symptoms, 34 patients (30.6%) with moderate symptoms, 7 patients (29%) with severe symptoms. There was one exitus due to scorpion stings in the study period. Fortyone (37%) patients were hospitalised and 7 patients (%63) had hospitalisation in the pediatric intensive care unit. Five patients (4%) received doxasozin and 19 (17%) patients had antivenom therapy. Hospitalization in the intensive care unit was required for seven cases. No patient presented sequelae at the hospital discharge. Conclusions: Scorpion stings in our region mostly end up with mild envenomation. Doxazosin also a prazosin analog, which is more easily available in our country can be considered as a treatment option in serious scorpion envenomations with significant sympathetic symptoms.

Scorpion Species with Smaller Body Sizes and Narrower Chelae Have the Highest Venom Potency

Scorpionism is a global health concern, with an estimation of over one million annual envenomation cases. Despite this, little is known regarding the drivers of scorpion venom potency. One widely held view is that smaller scorpions with less-developed chelae possess the most potent venoms. While this perception is often used as a guide for medical intervention, it has yet to be tested in a formal comparative framework. Here, we use a phylogenetic comparative analysis of 36 scorpion species to test whether scorpion venom potency, as measured using LD50, is related to scorpion body size and morphology. We found a positive relationship between LD50 and scorpion total length, supporting the perception that smaller scorpions possess more potent venoms. We also found that, independent of body size, scorpion species with long narrow chelae have higher venom potencies compared to species with more robust chelae. These results not only support the general perception of scorpion morphology and potency, but also the presence of an ecology trade-off with scorpions either selected for well-developed chelae or more potent venoms. Testing the patterns of venom variations in scorpions aids both our ecological understanding and our ability to address the global health burden of scorpionism.

Induced pathophysiological alterations by the venoms of the most dangerous Moroccan scorpions Androctonus mauretanicus and Buthus occitanus: A comparative pathophysiological and toxic-symptoms study

Scorpion envenomation is a serious public health issue. Androctonus mauretanicus (Am) and Buthus occitanus (Bo) are the most dangerous scorpions in Morocco. Despite their medical relevance, no study has yet related their kinetics of symptom apparition and the consequent tissue disorders at the same interval post-injection. This work achieved the first comparative pathophysiological and toxic-symptoms study between the Am and Bo venoms from a biochemical, toxicological and physiopathological standpoint. The activity of venoms and their subletal dose were determined by administration of increasing concentrations of the venoms. 30, 60 and 120 min following the experimental envenomation in mice, the profile of clinical symptoms was underlined and the main organs: brain, heart, lungs, liver and kidneys were removed for histological examination. The Am venom is a rich source of proteins and three-times more toxic than the Bo. The most observed clinical symptoms are neurological and cardiopulmonary. The Am venom caused histopathological alterations at 30, 60, and 120 min which were more important than the Bo. This study highlighted that both venoms exhibited a strong toxicity with variable intensities. Moreover, we showed the presence of correlation between the level of histopathological disorders observed and the intensity of signs appeared at the same time following venom inoculation.

Emotions triggered by live arthropods shed light on spider phobia

Spiders are mostly harmless, yet they often trigger high levels of both fear and disgust, and arachnophobia (the phobia of spiders) ranks among the most common specific animal phobias. To investigate this apparent paradox, we turned to the only close relatives of spiders that pose a real danger to humans: scorpions. We adopted a unique methodology in order to assess authentic emotions elicited by arthropods. Over 300 respondents were asked to rate live specimens of 62 arthropod species (including spiders, scorpions, cockroaches, and other insects) based on perceived fear, disgust, and beauty. We found that species' scores on all three scales depended on the higher taxon as well as on body size. Spiders, scorpions, and other arachnids scored the highest in fear and disgust, while beetles and crabs scored the highest in beauty. Moreover, all chelicerates were perceived as one cohesive group, distinct from other arthropods, such as insects or crabs. Based on these results, we hypothesize that the fear of spiders might be triggered by a generalized fear of chelicerates, with scorpions being the original stimulus that signals danger.

Relationship Between Scorpion Stings Events and Environmental Conditions in Mainland France

In the world, the impact of environmental conditions on the number of scorpion events was evaluated in North Africa,Middle East, and the Amazonian region but not in Europe. In mainland France, scorpion species described are Buthus occitanus (Amoreux, 1789), Belisarius xambeui (Simon, 1879) and 4 Euscorpiidae: Euscorpius concinnus (Koch, 1837), Euscorpius italicus (Herbst, 1800), Euscorpius tergestinus (Koch, 1837), and Tetratrichobothrius flavicaudis (De Geer, 1778). We aimed to describe the impact of environmental conduction on the number of scorpion events. For this, a retrospective multi-center study was conducted with data from the French poison control centers files about scorpion events between 1 January 2011 and 31 December 2020. During the study period, 975 incoming calls for scorpion events were recorded and 574 were related to scorpions native to mainland France and Corsica: B. occitanus (n = 86), Euscorpiidae species (n = 222), B. xambeui (n = 1), and undetermined species (n = 265). Cases were mostly reported along the Mediterranean coast, along rivers, and in cities with a trading port. The number of scorpion events was linked to the rivers' water level, rivers' flow, temperature, sunshine, and pluviometry (P < 0.05 for all variables). B. occitanus need warmest and driest environment than Euscorpiidae spp. A link between the severity of the envenoming and climatic condition or seasonality was not demonstrated.

Biochemical and Proteomic Characterization, and Pharmacological Insights of Indian Red Scorpion Venom Toxins

The Indian red scorpion (Mesobuthus tamulus) is one of the world's deadliest scorpions, with stings representing a life-threatening medical emergency. This species is distributed throughout the Indian sub-continent, including eastern Pakistan, eastern Nepal, and Sri Lanka. In India, Indian red scorpions are broadly distributed in western Maharashtra, Saurashtra, Kerala, Andhra Pradesh, Tamil Nadu, and Karnataka; however, fatal envenomations have been recorded primarily in the Konkan region of Maharashtra. The Indian red scorpion venom proteome comprises 110 proteins belonging to 13 venom protein families. The significant pharmacological activity is predominantly caused by the low molecular mass non-enzymatic Na+ and K+ ion channel toxins. Other minor toxins comprise 15.6% of the total venom proteome. Indian red scorpion stings induce the release of catecholamine, which leads to pathophysiological abnormalities in the victim. A strong correlation has been observed between venom proteome composition and local (swelling, redness, heat, and regional lymph node involvement) and systemic (tachycardia, mydriasis, hyperglycemia, hypertension, toxic myocarditis, cardiac failure, and pulmonary edema) manifestations. Immediate administration of antivenom is the preferred treatment for Indian red scorpion stings. However, scorpion-specific antivenoms have exhibited poor immunorecognition and neutralization of the low molecular mass toxins. The proteomic analysis also suggests that Indian red scorpion venom is a rich source of pharmacologically active molecules that may be envisaged as drug prototypes. The following review summarizes the progress made towards understanding the venom proteome of the Indian red scorpion and addresses the current understanding of the pathophysiology associated with its sting.

Risk factors for fatal scorpion envenoming among Brazilian children: a case-control study

BACKGROUND

Scorpion envenoming is relatively frequent in tropical and subtropical regions and potentially fatal. We aimed to identify risk factors for fatal scorpion envenoming among Brazilian children.

METHODS

A case-control study investigated all fatal cases of scorpion envenoming among children up to 10 y old, reported to the Brazilian Diseases Surveillance System between 1 January 2007 and 18 July 2016. Controls were randomly sampled from children who survived the envenoming over this period. Data were analysed using logistic regression.

RESULTS

Of the 254 cases and 1083 controls investigated, the identified risk factors were age ≤5 y, occurred in a rural area, time-to-treatment ≥3 h, treatment with scorpion antivenom (SAV) but either excessive or insufficient number of vials, treatment with antivenom that was neither SAV nor anti-spider and no antivenom administered compared with the standard recommended treatment. Treatment effectiveness at preventing fatal scorpion envenoming was 77.0% when time-to-treatment was <3 h and 75% in children 9-10 y of age. SAV was 63% effective at preventing death when administered early at the recommended dosage.

CONCLUSIONS

Fatal scorpion envenoming was associated with younger age, incident occurring in a rural area, late treatment and inadequate antivenom treatment. SAV was effective at preventing death when administered early.

Singapore First Aid Guidelines 2021

The Singapore Resuscitation and First Aid Council is updating the guidelines for first aid based on the latest evidence-based review from the International First Aid Taskforce Consensus on Science with Treatment Recommendations published in 2020. This is part of the regular updating of standards of care and training for first aid. This article presents some of the updated evidence-based approaches to first aid treatments in common emergencies such as asthma, chronic bronchitis, anaphylaxis, shock, unresponsiveness, seizure, heat disorders, ingested poisons, bleeding, head and spinal injury, bites and dental injuries. These updated treatments will be incorporated into the Standard and Child First Aid course syllabus in Singapore.

Ecological association between socioeconomic, occupational and sanitation factors and the occurrence of scorpionism in Brazil, 2007-2019

OBJECTIVE

To analyze ecological association between socioeconomic, occupational and sanitation characteristics and scorpionism in Brazil.

METHODS

This was an ecological study with data on scorpion sting accidents reported on the Notifiable Health Conditions Information System (2007-2019). Negative binomial regression was used to estimate incidence rate ratios (IRR) and confidence intervals (95%CI).

RESULTS

In the study period there were 1,079,333 scorpion sting accidents, with a cumulative incidence rate of 41.5/100,000 inhabitants. In the adjusted analysis, there was association with the municipal percentages of: women (IRR=1.65 - 95%CI 1.18;2.30) and men (IRR=0.90 - 95%CI 0.88;0.91) working in the construction industry, women (IRR=1.21 - 95%CI 1.18;1.25) and men (IRR=0.73 - 95%CI 0.69;0.77) working in domestic service, women (IRR=1.03 - 95%CI 1.02;1.04) and men (IRR=0.93 - 95%CI 0.92;0.93) working in farming, households with refuse collection (IRR=0.99 - 95%CI 0.98;0.99) and households with refuse left nearby (IRR=1.02 - 95%CI 1.01;1.02), expected years of schooling (IRR=0.88 - 95%CI 0.83;0.92), and unemployment rate (IRR=1.07 - 95%CI 1.05;1.09).

CONCLUSION

Scorpionism was associated with precarious infrastructure/sanitation, job availability, education and female occupation.

The lethality, histological, haematological and biochemical alterations in mice envenomated with Aegaeobuthus nigrocinctus venom

There is currently no data regarding the toxicity or the in vivo effects of the venom the Aegaeobuthus nigrocinctus species, since it has not been studied thus far according to the best of our knowledge. In the present study, and for the first time, the median lethal dose, the in vivo toxic effects, the histological changes in some of the vital organs were all determined as well as an assessment was made of the histological, biochemical and haematological changes which were caused by the venom injected in mice. The median lethal dose (LD₅₀) of the scorpion venom for mice was found to be 0.38 mg/kg in terms of body weight. The results of the study show that the A. nigrocintus is a potentially lethal scorpion. The evidence related to the venom indicated that it could cause tissue injury in some vital organs. In conclusion, this scorpion venom could cause significant medical complications, and may lead to death, regarding at-risk patients. Therefore, health professionals should be aware of the various scorpion species in their regions and should follow current medical approaches concerning scorpion envenomation.

The venom of the scorpion Centruroides limpidus, which causes the highest number of stings in Mexico, is neutralized by two recombinant antibody fragments

Phage display and directed evolution have made it possible to generate recombinant antibodies in the format of single chain variable fragments (scFvs) capable of neutralizing different toxins and venoms of Mexican scorpions. Despite having managed to neutralize a significant number of venoms, some others have not yet been completely neutralized, due to the diversity of the toxic components present in them. An example is the venom of the scorpion Centruroides limpidus, which contains three toxins of medical importance, called Cll1, Cll2 and Cl13. The first two are neutralized by scFv 10FG2, while Cl13, due to its sequence divergence, was not even recognized. For this reason, the aim of the present work was the generation of a new scFv capable of neutralizing Cl13 toxin and thereby helping to neutralize the whole venom of this scorpion. By hybridoma technology, a monoclonal antibody (mAb B7) was generated, which was able to recognize and partially neutralize Cl13 toxin. From mAb B7, its scFv format was obtained, named scFv B7 and subjected to three cycles of directed evolution. At the end of these processes, scFv 11F which neutralized Cl13 toxin was obtained. This scFv, administered in conjunction with scFv 10FG2, allowed to fully neutralize the whole venom of Centruroides limpidus scorpion.

Mass spectrometry-based top-down and bottom-up approaches for proteomic analysis of the Moroccan Buthus occitanus scorpion venom

Buthus occitanus (B. occitanus) is one of the most dangerous scorpions in the world. Despite the involvement of B. occitanus scorpion in severe cases of envenomation in Morocco, no study has focused yet on the proteomic composition of the Moroccan B. occitanus scorpion venom. Mass spectrometry‐based proteomic techniques are commonly used in the study of scorpion venoms. The implementation of top‐down and bottom‐up approaches for proteomic analyses facilitates screening by allowing a global view of the structural aspects of such complex matrices. Here, we provide a partial overview of the venom of B. occitanus scorpion, in order to explore the diversity of its toxins and hereafter understand their effects. To this end, a combination of top‐down and bottom‐up approaches was applied using nano‐high liquid chromatography coupled to nano‐electrospray tandem mass spectrometry (nano‐LC‐ESI MS/MS). The LC‐MS results showed that B. occitanus venom contains around 200 molecular masses ranging from 1868 to 16 720 Da, the most representative of which are those between 5000 and 8000 Da. Interestingly, combined top‐down and bottom‐up LC‐MS/MS results allowed the identification of several toxins, which were mainly those acting on ion channels, including those targeting sodium (NaScTxs), potassium (KScTxs), chloride (ClScTxs), and calcium channels (CaScTx), as well as antimicrobial peptides (AMPs), amphipathic peptides, myotropic neuropeptides, and hypothetical secreted proteins. This study reveals the molecular diversity of B. occitanus scorpion venom and identifies components that may have useful pharmacological activities.

Scorpionicidal activity of secondary metabolites from Paecilomyces sp. CMAA1686 against Tityus serrulatus

INTRODUCTION

Urban pests pose enormous risks to human health. Control initiatives are carried out in regions of high infestation and incidence of accidents caused by scorpions OBJECTIVE: In this study, we aimed to analyze the anti-scorpionic activity of fungal isolates obtained from a cemetery in Brazil.

MATERIALS AND METHODS

A total of thirteen fungi were subjected to a bioassay test against Tityus serrulatus, and the two isolates with the highest scorpionicidal activity were selected for molecular identification through sequencing of the ITS DNA hypervariable region and large-scale cultivation on liquid medium for secondary metabolite extraction. The crude extracts were partitioned by solid-phase extraction, and the resulting purified extracts were tested for anti-scorpionic activity. The extracts from one of the isolates presented better results and were submitted to UPLC-MS/MS. The metabolomics data were submitted to GNPS website for Molecular Networking and MASST searches. We also performed a MolNetEnhancer analysis to identify the chemical classes of the molecules found in the samples.

RESULTS

The most promising fungal isolate was identified as Paecilomyces sp. CMAA1686 which has 98% of similarity to Paecilomyces formosus. The sub-fractions C and D had the best activity against the scorpions (54 and 32% mortality, respectively). Molecular Networking and MolNetEnhancer revealed a range of molecular classes in our extracts that are known to include bioactive metabolites from Paecilomyces species.

CONCLUSIONS

The scorpionicidal activity of Paecilomyces sp. CMAA1686 and its secondary metabolites may provide new alternative compounds for biological and chemical control of scorpions from the species T. serrulatus. Paecilomyces sp. CMAA1686 is an isolate that has great potential for isolation of secondary metabolites.

Scorpions and scorpion sting envenoming (scorpionism) in the Arab Countries of the Middle East

The twelve Arab countries of the Middle East are inhabited by 117 species of scorpions of varying medical importance within six families. Scorpion stings are a very common occurrence throughout the region. Twenty-two scorpion species are considered to be dangerously venomous, causing potentially life threatening stings. Accessible literature in English and Arabic on scorpions, scorpion stings and available antivenoms was reviewed to document the scorpion fauna and scorpion stings in each country. Saudi Arabia, Iraq and Jordan report the highest numbers of stings and envenomings. Clinically, the most important toxins in Old World scorpion venoms are α-toxins that target voltage-gated sodium (Na_v) channels at neurotoxin binding site 3, causing sympathetic excitation and the endogenous release of catecholamines that is responsible for transient, but life-threatening myocardial damage. Most victims of scorpion stings suffer severe local pain, but a few, especially children, develop systemic envenoming which, in the case of most Middle Eastern buthid species, such as Androctonus and Leiurus species, is dominated by the cardiovascular and respiratory consequences of hypercatecholinaemic myocarditis. Other syndromes include paralysis (Parabuthus leiosoma), coagulopathy (Nebo hierichonticus and Hemiscorpius species), and local tissue damage, haemolysis and acute kidney injury (H. lepturus). Early antivenom treatment is recommended but its value remains controversial. However, intensive care, with the ancillary use of vasoactive drugs such as prazosin and dobutamine, has proved effective.

Coronavirus disease 2019: investigational therapies in the prevention and treatment of hyperinflammation

Introduction: The mortality of coronavirus disease 2019 (COVID-19) is frequently driven by an injurious immune response characterized by the development of acute respiratory distress syndrome (ARDS), endotheliitis, coagulopathy, and multi-organ failure. This spectrum of hyperinflammation in COVID-19 is commonly referred to as cytokine storm syndrome (CSS). Areas covered: Medline and Google Scholar were searched up until 15th of August 2020 for relevant literature. Evidence supports a role of dysregulated immune responses in the immunopathogenesis of severe COVID-19. CSS associated with SARS-CoV-2 shows similarities to the exuberant cytokine production in some patients with viral infection (e.g.SARS-CoV-1) and may be confused with other syndromes of hyperinflammation like the cytokine release syndrome (CRS) in CAR-T cell therapy. Interleukin (IL)-6, IL-8, and tumor necrosis factor-alpha have emerged as predictors of COVID-19 severity and in-hospital mortality. Expert opinion: Despite similarities, COVID-19-CSS appears to be distinct from HLH, MAS, and CRS, and the application of HLH diagnostic scores and criteria to COVID-19 is not supported by emerging data. While immunosuppressive therapy with glucocorticoids has shown a mortality benefit, cytokine inhibitors may hold promise as 'rescue therapies' in severe COVID-19. Given the arguably limited benefit in advanced disease, strategies to prevent the development of COVID-19-CSS are needed.

Factors involved in the resilience of incidence and decrease of mortality from scorpion stings in Mexico

In Mexico, scorpion sting envenomation (SSE) is a significant public health issue that has engaged the attention of health authorities for more than a century. Rigorously characterized today, scorpion sting incidence is stable around 230 stings per 100,000 population, i.e. 300,000 annual stings treated in Mexican health centers and hospitals. Higher incidence is observed mainly in central and Pacific Mexico. Scorpion populations thrive in populated places, particularly in impoverished areas. Scorpion stings occur in houses. This could explain similar incidence according to gender and age. The number of scorpion stings has remained stable since the mid-2000s. In contrast, mortality, which was over 1500 deaths per year before the 1960s, underwent a dramatic drop after the 1970s, from 500 deaths per year to fewer than 50 annual deaths today. Case fatality rates have shown similar trend. We noted a significantly higher specific mortality in males than in females (0.199 and 0.168 per 100,000 respectively; P < 1.9·10^-6). Three causes explained the drop in mortality and case fatality rate, a) ongoing improvement in hospital care, particularly in terms of supportive standardized treatments, b) the use of highly purified immunoglobulin F(ab')₂ fragments after 1995 and, c) increasing access to health services for most of the Mexican population. The authors retrace the history of the management of SSE, including the development of antivenoms, in Mexico between 1905 and today.