Utilization of dapsone and hemoglobin in the epithelial skin regeneration therapy of cutaneous loxoscelism: A case report and integrative literature review

ABSTRACT BACKGROUND: Loxosceles spp are arthropods found worldwide. Its bite may produce cutaneous loxoscelism (necrotic or edematous) or cutaneous-visceral loxoscelism. Depending on their severity and location, cutaneous forms are managed with local cold application and systemic administration of antihistamines, corticosteroids, antibiotics, polymorphonuclear inhibitors, and analgesics. OBJECTIVE: This study aimed to report a case of cutaneous loxoscelism and to identify the main dermatological manifestations associated with the Loxosceles spp bite. DESIGN AND SETTING: This case report and literature review was conducted in a Mexican university. METHODS: A detailed report on the medical management of a patient with cutaneous loxoscelism treated at the emergency department of a public hospital was published. Scopus, PubMed, Web of Science, and Google Scholar databases were searched to identify articles reporting cutaneous loxoscelism. The following keywords were used during the database search: "loxoscelism" OR "spider bite," OR "loxosceles" OR "loxosceles species" OR "loxosceles venom" OR "loxoscelism case report" AND "cutaneous" OR "dermonecrotic arachnidism." RESULTS: A 62-year-old female patient with cutaneous loxoscelism was treated with systemic dapsone and local heparin spray. Eighteen studies with 22 clinical cases were included in this systematic review. Of the 22 patients, 12 (54.5%) were men. L. rufescens was the predominant spider species. CONCLUSIONS: The administration of dapsone and heparin for the management of cutaneous loxoscelism demonstrated success in this case, with no sequelae observed. In general, the literature review indicated favorable outcomes in patients treated with antimicrobials and corticosteroids, with continuous healing of skin lesions. SYSTEMATIC REVIEW REGISTRATION: PROSPERO ID CRD42023422424 (https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023422424).

Cytotoxic effects of crotoxin from Crotalus durissus terrificus snake in canine mammary tumor cell lines

Background: Mammary gland tumors are the most prevalent neoplasm in intact female dogs, and they are good natural models to study comparative oncology. Most canine mammary malignancies, as in women, are commonly refractory to conventional therapies and demand continuous new therapeutic approaches. Crotalus durissus terrificus, also called rattlesnake, has more than 60 different proteins in its venom with multiple pharmaceutical uses, such as antitumor, antiviral, and antimicrobial action. Crotoxin, a potent β-neurotoxin formed by the junction of two subunits, a basic subunit (CB-PLA2) and an acidic subunit (crotapotin), has already been reported to have anticancer properties in different types of cancers. Methods: In this work, we describe the cytotoxic potential of crotoxin and its subunits compared to doxorubicin (drug of choice) in two canine mammary carcinoma cell lines. Results: Crotoxin, CB-PLA2, crotalic venom, and doxorubicin decreased cell viability and the ability to migrate in a dose-dependent manner, and crotapotin did not present an antitumoral effect. For all compounds, the predominant cell death mechanism was apoptosis. In addition, crotoxin did not show toxicity in normal canine mammary gland cells. Conclusion: Therefore, this work showed that crotoxin and CB-PLA2 had cytotoxic activity, migration inhibition, and pro-apoptotic potential in canine mammary gland carcinoma cell lines, making their possible use in cancer research.

An overview of some enzymes from buthid scorpion venoms from Colombia: Centruroides margaritatus, Tityus pachyurus, and Tityus n. sp. aff. metuendus

Background: In Colombia, several species of Buthidae scorpions belonging to the genera Centruroides and Tityus coexist, and their stings are considered life-threatening to humans because of their venom neurotoxins. Despite previous studies focusing on neurotoxins from these scorpion genera, little is known about the enzymes present in their venoms and their relationship with whole venom toxicity. Methods: Here, using proteomic and biochemical protocols the enzymatic activities of the venoms of three Colombian scorpion species, C. margaritatus, T. pachyurus, and T. n. sp. aff. metuendus, were compared to establish the presence and absence of enzymes such as phospholipases, hyaluronidases, and proteases that could be related to venom toxicity. Results: C. margaritatus was positive for hyaluronidases, T. n. sp. aff. metuendus for proteases, and T. pachyurus exhibited activity for all three mentioned enzymes. Conclusion: This information provides valuable insights into the specific enzyme diversity of each species' venom and their potential role in venom toxicity, which could contribute to the development of better treatments and prevention strategies for scorpion envenomation.

Alterações oculares decorrentes de picada de abelha na córnea / Ocular changes due to corneal bee sting

RESUMO O propósito deste estudo foi reportar as alterações oculares observadas após picada de abelha com ferrão retido na córnea. Destacamos o tratamento e o desfecho de uma lesão de córnea incomum e sua patogênese. Trata-se de relato de caso e revisão da literatura de lesões oculares por picada de abelha. Paciente do sexo feminino, 63 anos, procurou atendimento oftalmológico de urgência devido à picada de abelha na córnea do olho direito há 6 dias. Queixava-se de embaçamento visual, dor e hiperemia ocular. Apresentou acuidade visual de vultos no olho afetado. Ao exame, notaram-se hiperemia moderada de conjuntiva bulbar, edema corneano com dobras de Descemet e presença do ferrão alojado na região temporal, no estroma profundo da córnea. A paciente foi internada para ser abordada no centro cirúrgico sob anestesia geral. Durante a cirurgia, o ferrão teve que ser retirado via câmara anterior, mediante a realização de uma paracentese e uma lavagem da câmara anterior, com dupla via e solução salina balanceada. Ainda não existe na literatura um tratamento padrão na abordagem de pacientes com lesões oculares por picada de abelha, sendo importantes a identificação e o reconhecimento precoce de possíveis complicações que ameacem a visão.

ABSTRACT The purpose of this study was to report the ocular changes observed after a bee sting with a stinger retained in the cornea. We show the treatment and outcome of an unusual corneal injury and its pathogenesis. This is a case report and literature review of ocular injuries caused by bee stings. A 63-year-old female patient sought emergency ophthalmic care because of a bee sting on the cornea of her right eye six days before. She complained of blurred vision, pain, and ocular hyperemia. She had glare sensitivity on visual acuity in the affected eye. Examination revealed moderate hyperemia of the bulbar conjunctiva, corneal edema with Descemet's folds and a stinger lodged in the temporal region, in the deep stroma of the cornea. The patient was admitted to the operating room under general anesthesia. During surgery, the stinger had to be removed via the anterior chamber, by performing a paracentesis and washing the anterior chamber with a double flushing and balanced saline solution. There is still no standard treatment in the literature for patients with eye injuries caused by bee stings, and early identification and recognition of possible sight-threatening complications is important.

Actividad antiinflamatoria in vitro de Plantago major L. y Piper aduncum L. sobre la fosfolipasa A2 del veneno de la serpiente Lachesis muta muta / In vitro anti-inflammatory activity of Plantago major L. and Piper aduncum L. on phospholipase A2 from the venom of snake Lachesis muta muta

Objetivo. Evaluar la actividad inhibitoria in vitro de los extractos de Plantago major «llantén» y Piper aduncum «matico» sobre Fosfolipasa A2 (PLA2) del veneno de la serpiente Lachesis muta muta. Materiales y métodos. Esta investigación fue de tipo explicativa con diseño experimental. Se recolectaron hojas de P. major y P. aduncum en la provincia de Huarochirí en Lima, Perú. Se prepararon extractos alcohólicos diluidos en agua destilada y se realizaron los ensayos fitoquímicos, la cuantificación de fenoles y flavonoides, la cromatografía de capa fina (CCF) en celulosa y la actividad enzimática con PLA2. Se analizó la capacidad de inhibir la PLA2 con los extractos en estudio y sus fracciones. Para el análisis estadístico se utilizó la prueba de Kruskal Wallis y comparaciones múltiples de Bonferroni. Resultados. Tanto en P. major como en P. aduncum se identificó cualitativamente la presencia de fenoles, flavonoides y taninos; además, P. aduncum presentó saponinas. La inhibición de la actividad de la PLA2 del veneno por el extracto total de P. major fue del 45,3%, y sus fracciones mostraron valores de inhibición: LLF-1 con 31,1%, LLF-2 con 66,3% y LLF-3 con 65,5%. En P. aduncum, los valores de inhibición para el extracto total fueron de 86,9%, y sus fracciones presentaron inhibiciones: MF-1 con 34,3%, MF-2 con 67,1% y MF-3 con 54,9%. El análisis estadístico demostró diferencias significativas en la inhibición de la PLA2 (p=0,009) por los extractos. Conclusión. Los ensayos realizados demostraron una asociación entre el efecto antiinflamatorio de los extractos y la inhibición de la PLA2.

Objective. To evaluate the in vitro inhibitory activity of Plantago major "llantén" and Piper aduncum "matico" extracts on phospholipase A2 (PLA2) from the venom of the snake Lachesis muta muta. Materials and methods. We carried out an explanatory study with experimental design. Leaves of P. major and P. aduncum were collected in the province of Huarochirí in Lima, Peru. Then, we prepared alcoholic extracts diluted in distilled water and conducted phytochemical assays, quantification of phenols and flavonoids, thin layer chromatography (TLC) on cellulose and enzymatic activity with PLA2. The ability to inhibit PLA2 with the extracts under study and their fractions was analyzed. The Kruskal Wallis test and Bonferroni multiple comparisons were used during statistical analysis. Results. Phenols, flavonoids and tannins were qualitatively identified in both P. major and P. aduncum; in addition, P. aduncum presented saponins. The inhibition of PLA2 activity of the venom by the total extract of P. major was 45.3%, and its fractions showed the following inhibition values: 31.1% for LLF-1, 66.3% for LLF-2 and 65.5% for LLF-3. The inhibition values for the total extract of P. aduncum were 86.9%, and its fractions showed the following inhibition rates: 34.3% for MF-1, 67.1% for MF-2 and 54.9% for MF-3. Statistical analysis showed significant differences in the inhibition of PLA2 (p=0.009) by the extracts. Conclusion. The tests demonstrated an association between the anti-inflammatory effect of the extracts and PLA2 inhibition.

Segurança da vacinação contra a COVID-19 em doentes referenciados dos cuidados de saúde primários por alergia ao veneno de himenópteros / COVID-19 vaccination safety in patients with hymenoptera venom allergy referred by primary health care

Introdução: As reações de hipersensibilidade após vacinação contra a COVID-19 têm vindo a ser descritas, embora a anafilaxia seja rara. A hipersensibilidade ao veneno de himenópteros constitui a terceira causa mais frequente de anafilaxia em Portugal, embora não pareça aumentar o risco de anafilaxia à vacinação contra a COVID-19. Objetivos: Avaliar a segurança da vacinação contra a COVID-19 em doentes com história de alergia ao veneno de himenópteros referenciados dos Cuidados de Saúde Primários (CSP). Métodos: Estudo observacional retrospectivo com inclusão dos doentes com alergia ao veneno de himenópteros referenciados pelos CSP ao serviço de Imunoalergologia, para estratificação do risco de reações de hipersensibilidade à vacina contra o SARS-CoV-2, entre janeiro e dezembro de 2021. Resultados: No total, incluíram-se 18 doentes, 72% do sexo feminino, média de idades de 61±18 [21-89] anos. Na caracterização do tipo da reação ao veneno de himenópteros, as reações locais exuberantes corresponderam a 33% de todas as reações referidas. Quanto a sintomas sistêmicos de anafilaxia, foram referidos sintomas mucocutâneos (33%), respiratórios (28%), cardiovasculares (33%) e gastrointestinais (11%). A abelha foi o inseto mais frequentemente implicado (61%). Relativamente aos valores de triptase basal, 3 doentes apresentaram níveis acima do cut-off estabelecido de 11,4 ng/mL, tendo indicação formal para iniciar esquema de vacinação em meio hospitalar. Durante o processo vacinal registrou-se um total de 46 administrações em 18 doentes, todas sem intercorrências. Apenas 5 doentes foram vacinados em meio hospitalar, tendo sido os restantes encaminhados para os CSP. Os doentes com mastocitose confirmada ou suspeita foram submetidos à pré-medicação com anti-histamínico anti-H1 e anti- H2, bem como montelucaste, na véspera e no dia da vacinação. Conclusões: A vacinação contra a COVID-19 é segura em doentes com reação de hipersensibilidade ao veneno de himenópteros. O protocolo utilizado mostrou ser eficaz na segregação de doentes entre CSP e cuidados secundários/terciários.

Introduction: Despite numerous reports of hypersensitivity reactions to COVID-19 vaccination, anaphylaxis is rare. Although hypersensitivity reactions to hymenoptera venom are the third most common cause of anaphylaxis in Portugal, they don't appear to enhance the risk of anaphylactic reaction to COVID-19 vaccination. Objectives: To assess the safety of COVID-19 vaccination in patients with a history of hymenoptera venom allergy. Methods: This retrospective observational study included patients with hymenoptera venom allergy referred by primary health care to the Immunoallergology Outpatient Clinic of a tertiary hospital between January and December 2021 to stratify the risk of hypersensitivity reactions to the SARSCoV- 2 vaccine. Results: A total of 18 patients were included: 72% women; mean age 61 (SD, 18 [range 21-89]) years. One-third of all reported reactions to hymenoptera venom were large and local. Topical systemic symptoms of anaphylaxis were mucocutaneous (33%), respiratory (28%), cardiovascular (33%) and gastrointestinal (11%). The honeybee was the most frequently involved hymenoptera species (61%). The basal tryptase levels of 3 patients were above the established cut-off (11.4 ng/mL) and they were formally indicated for vaccination in a hospital setting. Concerning the vaccination process, 46 doses were administered to the 18 patients and no reactions were recorded. Only 5 patients were vaccinated in a hospital environment; the rest were referred to primary health care centers. Patients with confirmed or suspected mastocytosis were premedicated with anti-H1 and anti-H2 antihistamines, as well as montelukast, the day before and on the day of vaccination. Conclusions: COVID-19 vaccination is safe for patients with hypersensitivity to hymenoptera venom. The risk assessment protocol effectively designated patients to primary or secondary/tertiary health care.

Anaphylaxis and systemic mastocytosis caused by Solenopsis invicta stings / Anafilaxia e mastocitose sistêmica ocasionada pela Solenopsis invicta

Indolent systemic mastocytosis is a rare disease characterized by an increased number of mast cells in the bone marrow and other tissues, such as the liver, spleen, lymph nodes, and skin. Patients with indolent systemic mastocytosis and high serum tryptase levels are at risk for Hymenoptera venom-induced anaphylaxis. Hymenoptera venom immunotherapy in patients with specific IgE is safe and effective. While some patients can receive ultra-rush venom immunotherapy with minimal side effects, omalizumab effectively protects against anaphylaxis during the build-up phase.

A mastocitose sistêmica indolente é uma doença rara caracterizada por um número aumentado de mastócitos na medula óssea e em outros tecidos, como fígado, baço, linfonodos e pele. Pacientes com mastocitose sistêmica indolente e altos níveis séricos de triptase correm risco de anafilaxia induzida pelo veneno dos Hymenoptera. A imunoterapia com veneno de himenópteros em pacientes com IgE específica é segura e eficaz. Embora alguns pacientes possam receber imunoterapia com veneno ultrarrápido com efeitos colaterais mínimos, o omalizumabe protegeu efetivamente contra a anafilaxia durante a fase de acúmulo.

Comparing modified Lee and White method against 20-minute whole blood clotting test as bedside coagulation screening test in snake envenomation victims

Abstract Background: Twenty-minute whole blood clotting test (20WBCT) and Modified Lee and White (MLW) method are the most routinely employed bedside tests for detecting coagulopathic snake envenomation. Our study compared the diagnostic utility of MLW and 20WBCT for snakebite victims at a tertiary care hospital in Central Kerala, South India. Methods: This single-center study recruited 267 patients admitted with snake bites. 20WBCT and MLW were performed simultaneously at admission along with the measurement of Prothrombin Time (PT). The diagnostic utility of 20WBCT and MLW was determined by comparing the sensitivity (Sn), specificity (Sp), positive and negative predictive values, likelihood ratios, and accuracy at admission with an INR value > 1.4. Results: Out of 267 patients, 20 (7.5%) patients had VICC. Amongst those who had venom-induced consumption coagulopathy (VICC), MLW was prolonged for 17 patients, (Sn 85% 95% confidence interval [CI]: 61.1-96.0) whereas 20WBCT was abnormal for 11 patients (Sn 55%, 95% CI: 32.04-76.17). MLW and 20WBCT were falsely positive for the same patient (Sp 99.6%, 95% CI: 97.4-99.9%). Conclusion: MLW is more sensitive than 20WBCT to detect coagulopathy at the bedside amongst snakebite victims. However, further studies are necessary for standardizing bedside coagulation tests in snakebite cases.

Basic research on toxin of Solenopsis invicta / 药学实践杂志

Solenopsis invicta is a kind of invasive pest that causes serious damage to local agriculture, environment, and human health. They attack mainly with venom within stingers. Those who are allergic to the venom would suffer a systemic anaphylaxis, even fatal shock, after being stinged by these ants. Many studies reveal that their venom is mainly composed by water, insoluble alkaloids and trace proteins, within which alkaloids are the main cause of burning sensation and blisters, while allergic reactions are caused by proteins or peptides. The research progress of toxic substances in the venom of Solenopsis invicta as well as the roles and functions of each component were reviewed in this paper.

Fatal intracranial bleedings in a viper bite: A case report / 中华创伤杂志(英文版)

Viper bite envenomation represents a significant occupational hazard among agricultural workers in India. The viper bite envenomation is usually suspected when a patient presents with predominant local symptoms at the bitten site, including pain, swelling, and necrosis. Further, systemic findings such as diffuse intravascular coagulation, hypotension, and shock may alert physicians of viper bite envenomation rather than a neurotoxic snake bite. However, cerebral complications are rare in viper bites but may potentially fatal. Central nervous system involvement in a viper bite is either due to neurotoxins or hemorrhagins present in the venom, which may induce cerebral thrombosis, ischemia, infarction, and hemorrhage. Here we present a case of a previously healthy adult male who succumbed to extensive subarachnoid, intracerebral, and intraventricular hemorrhages involving bilateral cerebral hemispheres following viper snake bite envenomation. This report highlights the importance of anticipating cerebral complications in viper bite envenomation, a rare occurrence. It also emphasizes the need for early antisnake venom administration to prevent and control systemic envenomation and its complications.

Snake venom disintegrins update: insights about new findings

ABSTRACT Snake venom disintegrins are low molecular weight, non-enzymatic proteins rich in cysteine, present in the venom of snakes from the families Viperidae, Crotalidae, Atractaspididae, Elapidae, and Colubridae. This family of proteins originated in venom through the proteolytic processing of metalloproteinases (SVMPs), which, in turn, evolved from a gene encoding an A Disintegrin And Metalloprotease (ADAM) molecule. Disintegrins have a recognition motif for integrins in their structure, allowing interaction with these transmembrane adhesion receptors and preventing their binding to proteins in the extracellular matrix and other cells. This interaction gives disintegrins their wide range of biological functions, including inhibition of platelet aggregation and antitumor activity. As a result, many studies have been conducted in an attempt to use these natural compounds as a basis for developing therapies for the treatment of various diseases. Furthermore, the FDA has approved Tirofiban and Eptifibatide as antiplatelet compounds, and they are synthesized from the structure of echistatin and barbourin, respectively. In this review, we discuss some of the main functional and structural characteristics of this class of proteins and their potential for therapeutic use.

Network meta-analysis of the effectiveness and safety of 3 kinds of snake venom hemocoagulase drugs for hemostasis in abdominal surgery / 中国药房

OBJECTIVE To systematically evaluate the hemostatic effect and safety of snake venom hemocoagulase drugs in abdominal surgery， so as to provide evidence-based evidence for clinic. METHODS Retrieved from Embase， Cochrane Library， PubMed， China Biomedical Literature Database， CNKI and Wanfang database， randomized controlled trials （RCTs） about 3 kinds of snake venom hemocoagulase drugs （Hemocoagulase injection， Hemocoagulase Bothrops atrox for injection， Haemocoagulase Agkistrodon for injection） in abdominal surgery were collected from the establishment of the database to Aug. 2023. Screening， quality evaluation， and data extraction were conducted on literature according to the inclusion and exclusion criteria， and Cochrane 5.1 was used for literature quality evaluation. The risk bias diagram and network diagram were drawn by Stata 15.1 software， and the Bayesian network meta-analysis was carried out by using R 3.6.2 software and Markov chain-Monte Carlo method. RESULTS A total of 11 studies were included， involving 1 401 patients， 852 in the study group， and 549 in the control group. In terms of hemostatic effect， Hemocoagulase injection was significantly superior to Haemocoagulase Agkistrodon for injection [MD＝－2.45， 95%CI （－4.39，－0.24）， P＜0.05]， and the probability of reducing intraoperative bleeding was ranked as follows： Hemocoagulase injection＞hemocoagulase B. atrox for injection＞Haemocoagulase Agkistrodon for injection； in terms of safety， there was no statistically significant difference between the three snake venom hemocoagulase drugs and placebo （P＞0.05）. CONCLUSIONS The hemostatic effect of Hemocoagulase injection in abdominal surgery is significantly better than that of Haemocoagulase Agkistrodon for injection； all three snake venom hemocoagulase drugs have good safety.

Bioactive peptides from scorpion venoms: therapeutic scaffolds and pharmacological tools / 中国天然药物

Evolution and natural selection have endowed animal venoms, including scorpion venoms, with a wide range of pharmacological properties. Consequently, scorpions, their venoms, and/or their body parts have been used since time immemorial in traditional medicines, especially in Africa and Asia. With respect to their pharmacological potential, bioactive peptides from scorpion venoms have become an important source of scientific research. With the rapid increase in the characterization of various components from scorpion venoms, a large number of peptides are identified with an aim of combating a myriad of emerging global health problems. Moreover, some scorpion venom-derived peptides have been established as potential scaffolds helpful for drug development. In this review, we summarize the promising scorpion venoms-derived peptides as drug candidates. Accordingly, we highlight the data and knowledge needed for continuous characterization and development of additional natural peptides from scorpion venoms, as potential drugs that can treat related diseases.

Métodos alternativos para determinação da potência de veneno e antiveneno botrópico: aplicações e perspectivas para o controle da qualidade / Alternative methods for potency evaluation for Bothrops venom and antivenom: applications and perspectives for quality control

Introdução: Acidentes com animais peçonhentos são classificados como doenças tropicais negligenciadas e são atualmente a mais frequente causa de intoxicação em humanos no Brasil. O único tratamento disponível é a rápida administração de antivenenos específicos e de qualidade garantida. Para assegurar a eficácia e a segurança desses produtos, são realizados ensaios de determinação da potência in vivo para veneno e antiveneno, desde as etapas de produção até sua liberação final. Apesar dos diversos estudos sobre métodos   alternativos ao ensaio murino, nenhum método foi efetivamente validado. Objetivo: Compilar os métodos alternativos desenvolvidos para os antivenenos botrópicos, avaliando sua disponibilidade, perspectivas e aplicações em laboratórios de produção e controle da qualidade. Método: Foi realizada uma busca nas bases PubMed, BVS e Scopus entre novembro de 2021 e junho de 2022. Foram identificados 89 trabalhos, dos quais 31 foram selecionados de acordo com os critérios de elegibilidade. Resultados: Nos métodos alternativos identificados, observamos a preferência de 42,80% dos estudos por metodologias que utilizem linhagens celulares como método alternativo aos ensaios murinos, sendo que a maioria destes trabalhos 58,30% optou pela linhagem celular Vero. Conclusões: Pela diversidade das toxinas encontradas em cada gênero de serpentes, entende-se que é de extrema importância que o ensaio de potência dos antivenenos tenha como base a avaliação e a quantificação precisa da inibição da atividade biológica dos venenos. Ensaios de citotoxicidade são amplamente utilizados e têm acumulado evidências de sua adequação como importante ferramenta alternativa ao ensaio murino para o controle da qualidade de veneno e antiveneno antibotrópico.

Introduction: Accidents with venomous animals are classified as neglected tropical diseases and are currently the most frequent cause of intoxication in humans in Brazil. The only available treatment is the rapid administration of specific, quality-assured antivenoms. To ensure the efficacy and safety of these products, in vivo potency determination tests for venom and antivenom are performed during the production stages, until final release. Despite several studies on alternative methods to the murine assay, no method has been effectively validated. Objective: To compile alternative methods developed for Bothrops antivenoms, assessing the availability of the methods and the prospects and applications in Bothrops venom and antivenom production and quality control laboratories. Method: A search was conducted in PubMed, BVS, and Scopus databases between November 2021 and June 2022. 89 articles were identified, of which 31 were selected according to the eligibility criteria. Results: We observed in the alternative methods identified a preference of 42.80% of the studies for methodologies that use cell lines as an alternative method to the murine assays, and most of these works (58.30%) opted for a VERO cell line. Conclusions: Due to the diversity of toxins found in each genus of snakes, it is understood that the potency assay for antivenoms should be based on the evaluation and precise quantification of the inhibition of biological activity of venoms. Cytotoxicity assays are widely used and have been accumulating evidence of their suitability as an important alternative tool to the murine assay for quality control for Bothrops venom and antivenom.

Surveillance of venomous arthropods on a Nigerian Public University campus: An ecological study

Background: Venomous arthropods are arthropod species that use toxins for defense and offense. The objective of this study was to assess the biodiversity and abundance of venomous arthropods on the premises of Nnamdi Azikiwe University (NAU), Awka, Nigeria. Materials and Methods: Pitfall traps, sticky, and bait traps, beating and knockdown, and active search and handpicking with forceps were the methods used to collect various arthropods on the university campus. The data collected during this study were analyzed using the statistical package for social sciences version 23.0. Results: A total of 1,070 venomous arthropods were collected from the study areas, and they belong to four classes, six orders, fourteen families, and twenty-two species of the phylum Arthropoda. Conclusion: This study demonstrates that venomous arthropods are widespread on the NAU, Awka campus. Regular fumigation of the university premises is important in preventing human injuries, and infectious diseases carried by some arthropods.

Accidente Lonómico: Reporte de dos casos / Lonomic accident: Report of two cases

Resumen Introducción: dentro de los insectos del orden lepidóptero, la familia Saturniidae tiene más de 2.400 especies, allí se encuentran Hylesia y Lonomia. Objetivo: presentar dos casos de pacientes con accidente lonómico, el manejo y desenlace para reconocer la importancia de estos eventos en las regiones silvestres de la Orinoquia colombiana. Casos clínicos: paciente de 8 años proveniente de área rural quien refería contacto en región palmar de mano derecha con gusanos quién 48 horas después de dicho contacto presentó equimosis en extremidades, flictena sangrante en talón derecho, cefalea, escalofríos y artralgias, además se evidenciaron tiempos de coagulación prolongados. Paciente de 13 años de características similares a las del caso previamente descrito sin presentar manifestaciones clínicas, pero que presentaba tiempos de coagulación prolongados. Se consideró que cursaba con accidente lonómico por lo que se aplicaron 5 ampollas de suero antilonómico polivalente a cada una sin registrar reacciones adversas. En ambos casos cursaron con evolución clínica adecuada con disminución a rangos de seguridad de tiempos de coagulación. Conclusiones: el veneno lonómico actúa en la cascada de coagulación produciendo manifestaciones hemorrágicas de gravedad variable. El suero antilonómico es el único tratamiento eficaz, a pesar de estar disponible desde hace más de 20 años en Brasil hay un 5% de progresión a síndromes hemorrágicos severos y un 1.5 a 2% de mortalidad. A pesar de tener gran relevancia clínica en las Américas existe subregistro, es importante conocer sus manifestaciones y el manejo para así poder evitar complicaciones mortales.

Abstract Background: among the insects of the order Lepidoptera, the family Saturniidae has more than 2,400 species, there are Hylesia and Lonomia. Objective: to present two cases of patients with lonomic accident, the management and outcome to recognize the importance of these events in the wild regions of the Colombian orinoquia. Clinical case: an 8-year-old patient from a rural area who refers to contact in the palmar region of the right hand with worms for more than 48 hours, presents ecchymosis in the extremities, bleeding flictena in the right heel, headache, chills and arthralgias. Clotting times are performed which are prolonged. A 13-year-old patient who also referred contact without presenting clinical manifestations but presenting prolonged clotting times. They are considered to occur due to a lonomic accident, so 5 ampoules of polyvalent antilonomic serum are administered to each one without registering adverse reactions. They have an adequate clinical evolution with a decrease in the safe ranges of clotting times. Conclusions: the lonomic venom acts in the coagulation cascade producing hemorrhagic manifestations of variable severity. Antilonomic serum is the only effective treatment, despite being available for more than 20 years in Brazil, there is a 5% progression to severe hemorrhagic syndromes and 1.5 to 2% mortality. Despite being of great clinical relevance in the Americas, there is an underreporting, it is important to know its manifestations and management in order to avoid fatal complications.

A new approach of immunotherapy against Crotalus snakes envenoming: ostrich (Struthio camelus) egg yolk antibodies (IgY-technology) / Un nuevo enfoque de inmunoterapia contra el envenenamiento de serpientes Crotalus: anticuerpos de yema de huevo de avestruz (Struthio camelus) (tecnología IgY)

Abstract Crotalid envenomation is a neglected collective health problem involving many countries in America, which need secure and inexpensive snake anti-venom treatments. Here, high antibody titers (IgY) were raised in the Ostrich (Struthio camelus) egg yolk by immunizing with the venom of Venezuelan venomous Crotalus snakes. Ostriches were immunized with a pool of venoms from common rattlesnake (Crotalus durissus cumanensis), Uracoan rattlesnake (Crotalus vegrandis), Guayana rattlesnake (Crotalus durissus ruruima) and black rattlesnake (Crotalus pifanorum). The anti-snake venom antibodies were prepared from egg yolk by the water dilution method, enriched by the addition of caprylic acid (CA) and precipitation with ammonium sulfate at 30% (W/V). The purity and molecular mass of the final product was satisfactory, yielding a single ∼ 175 kDa band in SDS-PAGE gels ran under non-reducing conditions. In the immunoblot analysis, specific binding of the antivenom was observed with most venom proteins. The LD50 was 16.5 g/mouse (825 μg/kg body weight). High titers of IgY against Crot/pool venom were shown by ELISA. The median effective dose (ED50) was 19.66 mg/2LD50. IgY antibodies neutralized efficiently the Crot/pool venom lethality. As far as we know, this is the first anti-snake venom produced in ostriches, which could make this technology an affordable alternative for low-income countries, since it is likely to produce manteniabout 2-4 g of IgY per ostrich egg. Hence, almost 400 g of IgY can be purified from only one ostrich during a year. In addition, there are enormous differences in the cost of investment in the maintenance of horses, from the points of view of infrastructure, feeding and veterinary care, in which the cost can reach USD 100 per animal per day, compared to a maintenance cost of USD 146 per month per producing bird. These results are encouraging and could easily be extrapolated to the manufacturing of other antivenoms and antitoxins as well, as they could be applied to the manufacturing of potential diagnostic tools.

Resumen El envenenamiento por crotálidos es un problema de salud colectiva desatendido, que involucra a muchos países del continente americano, los cuales necesitan tratamientos seguros y económicos. En este trabajo, se obtuvieron títulos altos de anticuerpos (IgY) producidos en yema de huevo de avestruz (Struthio camelus) mediante la inmunización con el veneno de serpientes venezolanas del genero Crotalus. Se inmunizaron avestruces con una colección de veneno de serpientes de cascabel común (Crotalus durissus cumanensis), cascabel de Uracoa (Crotalus vegrandis), cascabel de Guayana (Crotalus durissus ruruima) y cascabel negra (Crotalus pifanorum). Los anticuerpos anti-veneno de serpiente se prepararon a partir de yema de huevo por el método de dilución en agua, enriquecidos mediante la adición de ácido caprílico (CA), seguido de una precipitación con sulfato de amonio al 30% (P/V). La pureza y masa molecular de los anticuerpos (IgY) se definieron mediante ensayos de SDS-PAGE nativos y las masas moleculares se establecieron electroforéticamente, obteniéndose una única banda de IgY de ∼ 175 kDa. El análisis de inmunotransferencia mostró la unión específica del antiveneno con la mayoría de las proteínas del veneno. La DL50 fue de 16,5 μg/ratón (825 μg / kg de peso corporal); Se mostraron títulos altos de IgY contra el veneno de Crot / pool mediante ELISA. La dosis mediana efectiva (DE50) fue de 19,66 mg/2 LD50. Los anticuerpos IgY neutralizaron eficazmente la letalidad del veneno de Crot / pool. Hasta donde sabemos, se trata del primer antídoto de serpiente producido en avestruces, lo que podría abaratar la producción de este tratamiento en países del tercer mundo. Ya que es probable que se obtengan alrededor de 2-4 g de IgY por huevo de avestruz. Por lo tanto, se podrían purificar casi 400 g de IgY de un solo avestruz durante un año. Asimismo, debido a las enormes diferencias en el costo de inversión en el mantenimiento de los caballos desde el punto de vista de infraestructura, alimentación y atención veterinaria, en los que el costo puede llegar a los 100 USD por día, frente a los 146 USD por mes de mantenimiento de la producción de aves. Estos resultados abren un campo terapéutico, para la fabricación de otros antivenenos contra un amplio espectro de toxinas y también como probables herramientas de diagnóstico.

Comparative venomic profiles of three spiders of the genus Phoneutria

Spider venoms induce different physio-pharmacological effects by binding with high affinity on molecular targets, therefore being of biotechnological interest. Some of these toxins, acting on different types of ion channels, have been identified in the venom of spiders of the genus Phoneutria, mainly from P. nigriventer. In spite of the pharmaceutical potential demonstrated by P. nigriventer toxins, there is limited information on molecules from venoms of the same genus, as their toxins remain poorly characterized. Understanding this diversity and clarifying the differences in the mechanisms of action of spider toxins is of great importance for establishing their true biotechnological potential. This prompted us to compare three different venoms of the Phoneutria genus: P. nigriventer (Pn-V), P. eickstedtae (Pe-V) and P. pertyi (Pp-V). Methods: Biochemical and functional comparison of the venoms were carried out by SDS-PAGE, HPLC, mass spectrometry, enzymatic activities and electrophysiological assays (whole-cell patch clamp). Results: The employed approach revealed that all three venoms had an overall similarity in their components, with only minor differences. The presence of a high number of similar proteins was evident, particularly toxins in the mass range of ~6.0 kDa. Hyaluronidase and proteolytic activities were detected in all venoms, in addition to isoforms of the toxins Tx1 and Tx2-6. All Tx1 isoforms blocked Nav1.6 ion currents, with slight differences. Conclusion: Our findings showed that Pn-V, Pe-V and Pp-V are highly similar concerning protein composition and enzymatic activities, containing isoforms of the same toxins sharing high sequence homology, with minor modifications. However, these structural and functional variations are very important for venom diversity. In addition, our findings will contribute to the comprehension of the molecular diversity of the venoms of the other species from Phoneutria genus, exposing their biotechnological potential as a source for searching for new active molecules.(AU)

Antimicrobial activity and partial chemical structure of acylpolyamines isolated from the venom of the spider Acanthoscurria natalensis

Background: Acylpolyamines are one of the main non-peptide compounds present in spider venom and represent a promising alternative in the search for new molecules with antimicrobial action. Methods: The venom of Acanthoscurria natalensis spider was fractionated by reverse-phase liquid chromatography (RP-HPLC) and the antimicrobial activity of the fractions was tested using a liquid growth inhibition assay. The main antimicrobial fraction containing acylpolyamines (ApAn) was submitted to two additional chromatographic steps and analyzed by MALDI-TOF. Fractions of interest were accumulated for ultraviolet (UV) spectroscopy and ESI-MS/MS analysis and for minimum inhibitory concentration (MIC) and hemolytic activity determination. Results: Five acylpolyamines were isolated from the venom with molecular masses between 614 Da and 756 Da, being named ApAn728, ApAn614a, ApAn614b, ApAn742 and ApAn756. The analysis of UV absorption profile of each ApAn and the fragmentation pattern obtained by ESI-MS/MS suggested the presence of a tyrosyl unit as chromophore and a terminal polyamine chain consistent with structural units PA43 or PA53. ApAn presented MIC between 128 µM and 256 µM against Escherichia coli and Staphylococcus aureus, without causing hemolysis against mouse erythrocytes. Conclusion: The antimicrobial and non-hemolytic properties of the analyzed ApAn may be relevant for their application as possible therapeutic agents and the identification of an unconventional chromophore for spider acylpolyamines suggests an even greater chemical diversity.(AU)

A new therapeutic approach for bone metastasis in colorectal cancer: intratumoral melittin

Background: Melittin has shown antiproliferative effects on tumor cells. Therefore, it comprises a valuable compound for studies on cancer treatment. To the best of our knowledge, no studies have reported melittin effects on bone metastasis. Herein, we propose an approach based on intrametastatic melittin injection to treat bone metastases in colorectal cancer. Methods: Following the characterization of melittin and antiproliferative tests in vitro, a single dose was injected through intrametastatic route into the mouse bone metastasis model. Following treatment, metastasis growth was evaluated. Results: A single dose of melittin was able to inhibit metastasis growth. Histological analysis showed necrosis and inflammatory processes in melittin-treated metastasis. Except by mild weight loss, no other systemic effects were observed. Conclusion: Our data suggest that melittin might be a promising agent for the future development of treatment strategies aiming to reduce the bone metastasis skeletal-related impact in colorectal cancer patients with bone metastasis.(AU)