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.

Taiwan cobra envenoming: serum venom concentration before and after specific treatment and relationship with debridement of necrotic wound tissue

Background: Bivalent freeze-dried neurotoxic (FN) antivenom has been the primary treatment since the 1980s for Taiwan cobra (Naja atra) envenomation in Taiwan. However, envenomation-related wound necrosis is a significant problem after cobra snakebites. In the present study, we analyzed the changes in serum venom concentration before and after antivenom administration to discover their clinical implications and the surgical treatment options for wound necrosis. Methods: The patients were divided into limb swelling and wound necrosis groups. The clinical outcome was that swelling started to subside 12 hours after antivenom treatment in the first group. Serum venom concentrations before and after using antivenoms were measured to assess the antivenom's ability to neutralize the circulating cobra venom. The venom levels in wound wet dressing gauzes, blister fluids, and debrided tissues were also investigated to determine their clinical significance. We also observed the evolutional changes of wound necrosis and chose a better wound debridement timing. Results: We prospectively enrolled 15 Taiwan cobra snakebite patients. Males accounted for most of this study population (n = 11, 73%). The wound necrosis group received more antivenom doses than the limb swelling group (4; IQR:2-6 vs 1; IQR:1-2, p = 0.05), and less records of serum venom concentrations changed before/after antivenom use (p = 0.0079). The necrotic wound site may release venom into circulation and cause more severe envenomation symptoms. Antivenom can efficiently diminish limb swelling in cobra bite patients. However, antivenom cannot reduce wound necrosis. Patients with early debridement of wound necrosis had a better limb outcome, while late or without debridement may have long-term hospital stay and distal limb morbidity. Conclusions: Antivenom can efficiently eliminate the circulating cobra venom in limb swelling patients without wound necrosis. Early debridement of the bite site wound and wet dressing management are suggestions for preventing extended tissue necrosis and hospital stay.(AU)

Glutamine ameliorates Bungarus multicinctus venom-induced lung and heart injury through HSP70: NF-κB p65 and P53/PUMA signaling pathways involved

Background: Bungarus multicinctus is one of the most dangerous venomous snakes prone to cardiopulmonary damage with extremely high mortality. In our previous work, we found that glutamine (Gln) and glutamine synthetase (GS) in pig serum were significantly reduced after Bungarus multicinctus bite. In the present study, to explore whether there is a link between the pathogenesis of cardiopulmonary injury and Gln metabolic changes induced by Bungarus multicinctus venom. We investigated the effect of Gln supplementation on the lung and heart function after snakebite. Methods: We supplemented different concentrations of Gln to mice that were envenomated by Bungarus multicinctus to observe the biological behavior, survival rate, hematological and pathological changes. Gln was supplemented immediately or one hour after the venom injection, and then changes in Gln metabolism were analyzed. Subsequently, to further explore the protective mechanism of glutamine on tissue damage, we measured the expression of heat-shock protein70 (HSP70), NF-κB P65, P53/PUMA by western blotting and real-time polymerase in the lung and heart. Results: Gln supplementation delayed the envenoming symptoms, reduced mortality, and alleviated the histopathological changes in the heart and lung of mice bitten by Bungarus multicinctus. Additionally, Gln increased the activity of glutamine synthetase (GS), glutamate dehydrogenase (GDH) and glutaminase (GLS) in serum. It also balanced the transporter SLC7A11 expression in heart and lung tissues. Bungarus multicinctus venom induced the NF-κB nuclear translocation in the lung, while the HO-1 expression was suppressed. At the same time, venom activated the P53/PUMA signaling pathway and the BAX expression in the heart. Gln treatment reversed the above phenomenon and increased HSP70 expression. Conclusion: Gln alleviated the glutamine metabolism disorder and cardiopulmonary damage caused by Bungarus multicinctus venom. It may protect lungs and heart against venom by promoting the expression of HSP70, inhibiting the activation of NF-κB and P53/PUMA, thereby delaying the process of snake venom and reducing mortality. The present results indicate that Gln could be a potential treatment for Bungarus multicinctus bite.

Phylogeography of cliff racer (Platyceps rhodorachis Jan, 1865) from Punjab, Pakistan / Filografia de penhasco (Platyceps rhodorachis Jan, 1865) de Punjab, Paquistão

The present study reports the existence of cliff racer, Platyceps rhodorachis from the plains of Punjab, Pakistan. A total of 10 specimens were captured during the field surveys from June to September, 2018 from different sites of Punjab. Platyceps rhodorachis was identify on the basis of morphology and confirmed through COI gene sequences. The obtained DNA sequences have shown reliable and exact species identification. Newly produced DNA sequences of Platyceps rhodorachis were submitted to GenBank and accession numbers were obtained (MK936174.1, MK941839.1 and MT790210.1). N-J tree based on COI sequences of Platyceps rhodorachis clearly separated as out-group with other members of family Colubridae based on p-distance. The intra-specific genetic variation ranges from 12% to 18%. The DNA sequences of Platyceps rhodorachis kashmirensis, Platyceps rhodorachis ladacensis, Platyceps ventromaculatus, Platyceps ventromaculatus bengalensis and Platyceps ventromaculatus indusai are not available at NCBI to validate their taxonomic positions. In our recommendations, a large scale molecular based identification of Pakistan’s herpetofauna is required to report more new or subspecies from country.

O presente estudo relata a existência de um corredor de penhasco, Platyceps rhodorachis, das planícies de Punjab, Paquistão. Um total de 10 espécimes foi capturado durante os levantamentos de campo de junho a setembro de 2018 em diferentes locais de Punjab. Platyceps rhodorachis foi identificada com base na morfologia e confirmada por meio de sequências do gene COI. As sequências de DNA obtidas mostraram identificação de espécies confiável e exata. Sequências de DNA de Platyceps rhodorachis recém-produzidas foram submetidas ao GenBank e os números de acesso foram obtidos (MK936174.1, MK941839.1 e MT790210.1). Árvore N-J baseada em sequências COI de Platyceps rhodorachis claramente separadas como out-group com outros membros da família Colubridae com base na distância-p. A variação genética intraespecífica varia de 12% a 18%. As sequências de DNA de Platyceps rhodorachis kashmirensis, Platyceps rhodorachis ladacensis, Platyceps ventromaculatus, Platyceps ventromaculatus bengalensis e Platyceps ventromaculatus indusai não estão disponíveis no NCBI para validar suas posições taxonômicas. Em nossas recomendações, uma identificação de base molecular em grande escala da herpetofauna do Paquistão é necessária para relatar mais novas ou subespécies do país.

Phylogeography of cliff racer (Platyceps rhodorachis Jan, 1865) from Punjab, Pakistan / Filografia de penhasco (Platyceps rhodorachis Jan, 1865) de Punjab, Paquistão

The present study reports the existence of cliff racer, Platyceps rhodorachis from the plains of Punjab, Pakistan. A total of 10 specimens were captured during the field surveys from June to September, 2018 from different sites of Punjab. Platyceps rhodorachis was identify on the basis of morphology and confirmed through COI gene sequences. The obtained DNA sequences have shown reliable and exact species identification. Newly produced DNA sequences of Platyceps rhodorachis were submitted to GenBank and accession numbers were obtained (MK936174.1, MK941839.1 and MT790210.1). N-J tree based on COI sequences of Platyceps rhodorachis clearly separated as out-group with other members of family Colubridae based on p-distance. The intra-specific genetic variation ranges from 12% to 18%. The DNA sequences of Platyceps rhodorachis kashmirensis, Platyceps rhodorachis ladacensis, Platyceps ventromaculatus, Platyceps ventromaculatus bengalensis and Platyceps ventromaculatus indusai are not available at NCBI to validate their taxonomic positions. In our recommendations, a large scale molecular based identification of Pakistans herpetofauna is required to report more new or subspecies from country.(AU)

O presente estudo relata a existência de um corredor de penhasco, Platyceps rhodorachis, das planícies de Punjab, Paquistão. Um total de 10 espécimes foi capturado durante os levantamentos de campo de junho a setembro de 2018 em diferentes locais de Punjab. Platyceps rhodorachis foi identificada com base na morfologia e confirmada por meio de sequências do gene COI. As sequências de DNA obtidas mostraram identificação de espécies confiável e exata. Sequências de DNA de Platyceps rhodorachis recém-produzidas foram submetidas ao GenBank e os números de acesso foram obtidos (MK936174.1, MK941839.1 e MT790210.1). Árvore N-J baseada em sequências COI de Platyceps rhodorachis claramente separadas como out-group com outros membros da família Colubridae com base na distância-p. A variação genética intraespecífica varia de 12% a 18%. As sequências de DNA de Platyceps rhodorachis kashmirensis, Platyceps rhodorachis ladacensis, Platyceps ventromaculatus, Platyceps ventromaculatus bengalensis e Platyceps ventromaculatus indusai não estão disponíveis no NCBI para validar suas posições taxonômicas. Em nossas recomendações, uma identificação de base molecular em grande escala da herpetofauna do Paquistão é necessária para relatar mais novas ou subespécies do país.(AU)

Two records of xanthism in Corallus hortulana (Serpentes: Boidae) in Bolivia with comments on the yellow, patternless morphotype / Dos registros de xantismo en Corallus hortulana (Serpentes: Boidae) en Bolivia con comentarios sobre el morfotipo amarillo sin patrón

Snakes display a wide range of skin colors and patterns, acting in ecological, behavioral, and physiological roles. Xanthism has been reported in numerous snake species, including many neotropical taxa. Corallus hortulana is a polychromatic species widely distributed throughout South America. Yellow, patternless individuals, while rare, have been recognized as within the species' polychromatic range. We report the first yellow, patternless specimens of Corallus hortulana collected in Bolivia and discuss whether these individuals fit the criteria of xanthism.(AU)

Las serpientes muestran una amplia gama de colores y patrones de piel, actuando en roles ecológicos, de comportamiento y fisiológicos. Además, se ha informado xantismo en numerosas especies de serpientes, incluidos muchos taxones neotropicales. Corallus hortulana es una especie policromática ampliamente distribuida en América del Sur. Los individuos amarillos sin patrón, aunque raros, se han reconocido dentro del rango policromático de la especie. Reportamos los primeros especímenes amarillos sin patrón de Corallus hortulana recolectados en Bolivia y discutimos si estos individuos cumplen con los criterios de xantismo.(AU)

Guidelines for the diagnosis and differential diagnosis of snakebite envenoming of ruminants in Brazil / Diretrizes para o diagnóstico e diagnóstico diferencial de envenenamento por picadas de cobra em ruminantes no Brasil

In Brazil, snakebites are often cited as a cause of mortality in ruminants, but there are discrepancies in the literature regarding its actual prevalence, either by lack of diagnosis or by mistakes in the differential diagnosis. Among the factors that hinder the diagnosis are included the inconsistencies to distinguish between accidents caused by Bothrops and Crotalus, responsible for over 90% of the cases. For the diagnosis of accidents involving Lachesis muta, both the neurotropic and the proteolytic/hemolytic effects must be considered, similar to what is described in Crotalus scutulatus. This article describes the main clinical, pathological, and laboratory findings observed in envenoming by the aforementioned snakes and suggests procedures for establishing the diagnosis and differential diagnosis starting from a logical sequence, based on epidemiological evidence, clinical, laboratory, and pathological findings.

No Brasil, acidentes ofídicos são frequentemente citados como causa de mortalidade em ruminantes, mas existem discrepâncias em relação a sua atual prevalência, seja por falta de diagnóstico ou por erros no diagnóstico diferencial. Entre os fatores que dificultam o diagnóstico estão as inconsistências para distinguir entre os acidentes causados por Bothrops e Crotalus, responsáveis por mais de 90% dos casos. Para o diagnóstico de envenenamentos por Lachesis muta, devem ser considerados os efeitos neurotrópico e proteolítico/hemolíticos concomitantes, a exemplo do que ocorre com algumas cascavéis norte-americanas (Crotalus scutulatus, entre elas). Este artigo descreve os principais achados clinicopatológicos e laboratoriais observados em casos de envenenamento pelas serpentes citadas e sugere um roteiro simplificado para o estabelecimento do diagnóstico e diagnóstico diferencial, a partir de uma sequência lógica, baseada em evidências epidemiológicas e achados clínicos, laboratoriais e patológicos.

ß-micrustoxin (Mlx-9), a PLA2 from Micrurus lemniscatus snake venom: biochemical characterization and anti-proliferative effect mediated by p53

Background: Endogenous phospholipases A2 (PLA2 ) play a fundamental role in inflammation, neurodegenerative diseases, apoptosis and cellular senescence. Neurotoxins with PLA2 activity are found in snake venoms from the Elapidae and Viperidae families. The mechanism of action of these neurotoxins have been studied using hippocampal and cerebellar neuronal cultures showing [Ca2+]i increase, mitochondrial depolarization and cell death. Astrocytes are rarely used as a model, despite being modulators at the synapses and responsible for homeostasis and defense in the central nervous system. Preserving the cell division ability, they can be utilized to study the cell proliferation process. In the present work cultured astrocytes and glioblastoma cells were employed to characterize the action of ß-micrustoxin (previously named Mlx-9), a PLA2 isolated from Micrurus lemniscatus snake venom. The ß-micrustoxin structure was determined and the cell proliferation, cell cycle phases and the regulatory proteins p53, p21 and p27 were investigated. Methods: ß-micrustoxin was characterized biochemically by a proteomic approach. Astrocytes were obtained by dissociation of pineal glands from Wistar rats; glioblastoma tumor cells were purchased from ATCC and Sigma and cultured in DMEM médium. Cell viability was evaluated by MTT assay; cell proliferation and cell cycle phases were analyzed by flow cytometry; p53, p21 and p27 proteins were studied by western blotting and immunocytochemistry. Results: Proteomic analysis revealed fragments on ß-micrustoxin that aligned with a PLA2 from Micrurus lemniscatus lemniscatus previously identified as transcript ID DN112835_C3_g9_i1/m.9019. ß-micrustoxin impaired the viability of astrocytes and glioblastoma tumor cells. There was a reduction in cell proliferation, an increase in G2/M phase and activation of p53, p21 and p27 proteins in astrocytes. Conclusion: These findings indicate that ß-micrustoxin from Micrurus lemniscatus venom could inhibit cell proliferation through p53, p21 and p27 activation thus imposing cell cycle arrest at the checkpoint G2/M.(AU)

Bothrops envenomation in dogs: local and systemic manifestations

Background: Snakebite envenoming is a condition that affects humans and domestic animals worldwide. Identification of the snake species involved in the envenomation is infrequent. Bothrops envenomation presents typical clinicopathological features. This report describes epidemiological, clinical, and pathological data of 2 cases of Bothrops envenomation in dogs, including the first case of Bothrops moojeni snake striking a domestic animal in Brazil. Cases: Case 1. A dog was witnessed to have a Bothrops moojeni snakebite on a farm. In the first 24 h, acute lameness, pain, diffuse swelling, focal bleeding at the left forelimb, and increased whole-blood clotting time were observed in the envenomed dog. Polyvalent antivenom was administered in addition to fluid therapy, analgesics, corticosteroids, and antibiotics. On the 5th day, the animal presented spontaneous bleeding at the wound site, thrombocytopenia, and increased whole-blood clotting time. An additional dose of polyvalent antivenom was administered, and local treatment at the snakebite site was initiated. After 13 days, the dog showed no clinical or laboratory changes and recovered entirely. Case 2. A mongrel dog was taken for a necropsy to determine the cause of death. Grossly, major findings included swelling in the nasal plane that extended to the neck and dissecting hemorrhage in the subcutaneous tissue and adjacent musculature. Hemorrhages were observed in the heart, parietal pleura, left forelimb, lumbar region, and perirenal tissue. Marked necrosis and disruption of small blood vessels and lymphatics within the deep dermis and subcutaneous tissue were the main microscopic findings close to the snakebite site. Additionally, degeneration and necrosis of muscle fibers and dissecting hemorrhage were observed in the head and neck tissues surrounding the snakebite site. Kidneys showed marked interstitial hemorrhage and acute tubular nephrosis. Discussion: Bothrops envenoming is characterized by local (hemorrhage, dermonecrosis, and myonecrosis) and systemic (coagulative disorders, systemic hemorrhage, and acute kidney injury) changes due to the effect of the main venom components such as phospholipase A2 and metalloproteinases. These changes are hallmarks for the bothropic envenomation, supporting the diagnosis in cases 1 and 2. In case 1, the dog developed a Bothrops moojeni snakebite envenomation, but the immediate treatment with antivenom allowed a favorable outcome. In case 2, gross and microscopic findings supported the presumptive diagnosis of fatal bothropic envenomation. A marked local reaction such as swelling, pain, bleeding, bruising, and tissue necrosis was observed in case 1. In case 2, the most significant local changes were swelling and edema at the head and neck, hemorrhage in the subcutaneous tissue, and adjacent musculature. Systemic effects were observed clinically as spontaneous bleeding, thrombocytopenia, increased whole-blood clotting time (Case 1), systemic hemorrhages, and acute tubular nephrosis (Case 2). A proper treatment probably prevented the development of acute renal failure in Case 1. Herein, we show the first case of accidental snakebite envenomation by B. moojeni in a dog in Brazil. Information is scarce on the identification of venomous snake species striking domestic animals. Fast detection of well-determined clinical and pathological findings of Bothrops envenomation is essential for a correct diagnosis, therapeutics, and a good prognosis, even in cases with an unknown history.

Compositional and toxicological investigation of pooled venom from farm-raised Naja atra

Background: Naja atra is a venomous snake species medically relevant in China. In the current study, we evaluated the composition and toxicological profile of venom collected from farm-raised N. atra. Methods: Venom was collected from third-generation captive bred N. atra on a snake farm in Hunan Province, China. The venom was analyzed using sodium dodecyl sulfate polyacrylamide gel electrophoresis and nano-liquid chromatography with electrospray ionization tandem mass spectrometry. In addition, hemolytic activity, median lethal dose, serum biochemical and histopathological parameters were accessed. Results: N. atra venom proteome was dominated by phospholipase A2 (46.5%) and three-finger toxins (41.4 %), and a set of common low relative abundance proteins, including cysteine-rich secretory proteins (4.7%), NGF-beta (2.4%), snake venom metalloproteinase (1.5%), glutathione peroxidase (0.6%), vespryn (0.3%), and 5ʹ-nucleotidases (0.2%) were also found. Furthermore, the venom exhibited direct hemolytic activity, neurotoxicity, myotoxicity, and high lethal potency in mice, with a subcutaneous median lethal dose of 1.02 mg/kg. Histopathological analysis and serum biochemical tests revealed that venom caused acute hepatic, pulmonary and renal injury in mice. Conclusion: This study revealed the composition and toxicity of venom collected from farm-raised N. atra, thereby providing a reference for the analysis of venom samples collected from captive-born venomous snakes in the future.(AU)

Compositional and toxicological investigation of pooled venom from farm-raised Naja atra

Abstract Background: Naja atra is a venomous snake species medically relevant in China. In the current study, we evaluated the composition and toxicological profile of venom collected from farm-raised N. atra. Methods: Venom was collected from third-generation captive bred N. atra on a snake farm in Hunan Province, China. The venom was analyzed using sodium dodecyl sulfate polyacrylamide gel electrophoresis and nano-liquid chromatography with electrospray ionization tandem mass spectrometry. In addition, hemolytic activity, median lethal dose, serum biochemical and histopathological parameters were accessed. Results: N. atra venom proteome was dominated by phospholipase A2 (46.5%) and three-finger toxins (41.4 %), and a set of common low relative abundance proteins, including cysteine-rich secretory proteins (4.7%), NGF-beta (2.4%), snake venom metalloproteinase (1.5%), glutathione peroxidase (0.6%), vespryn (0.3%), and 5-nucleotidases (0.2%) were also found. Furthermore, the venom exhibited direct hemolytic activity, neurotoxicity, myotoxicity, and high lethal potency in mice, with a subcutaneous median lethal dose of 1.02 mg/kg. Histopathological analysis and serum biochemical tests revealed that venom caused acute hepatic, pulmonary and renal injury in mice. Conclusion: This study revealed the composition and toxicity of venom collected from farm-raised N. atra, thereby providing a reference for the analysis of venom samples collected from captive-born venomous snakes in the future.

New multienzymatic complex formed between human cathepsin D and snake venom phospholipase A2

Background Cathepsin D (CatD) is a lysosomal proteolytic enzyme expressed in almost all tissues and organs. This protease is a multifunctional enzyme responsible for essential biological processes such as cell cycle regulation, differentiation, migration, tissue remodeling, neuronal growth, ovulation, and apoptosis. The overexpression and hypersecretion of CatD have been correlated with cancer aggressiveness and tumor progression, stimulating cancer cell proliferation, fibroblast growth, and angiogenesis. In addition, some studies report its participation in neurodegenerative diseases and inflammatory processes. In this regard, the search for new inhibitors from natural products could be an alternative against the harmful effects of this enzyme. Methods An investigation was carried out to analyze CatD interaction with snake venom toxins in an attempt to find inhibitory molecules. Interestingly, human CatD shows the ability to bind strongly to snake venom phospholipases A2 (svPLA2), forming a stable muti-enzymatic complex that maintains the catalytic activity of both CatD and PLA2. In addition, this complex remains active even under exposure to the specific inhibitor pepstatin A. Furthermore, the complex formation between CatD and svPLA2 was evidenced by surface plasmon resonance (SPR), two-dimensional electrophoresis, enzymatic assays, and extensive molecular docking and dynamics techniques. Conclusion The present study suggests the versatility of human CatD and svPLA2, showing that these enzymes can form a fully functional new enzymatic complex.

Venom composition of Trimeresurus albolabris, T. insularis, T. puniceus and T. purpureomaculatus from Indonesia

Background: Several studies have been published on the characterization of Trimeresurus venoms. However, there is still limited information concerning the venom composition of Trimeresurus species distributed throughout Indonesia, which contributes to significant snakebite envenomation cases. The present study describes a comparative on the composition of T. albolabris, T. insularis, T. puniceus, and T. purpureomaculatus venoms originated from Indonesia. Methods: Protein content in the venom of four Trimeresurus species was determined using Bradford assay, and the venom proteome was elucidated using one-dimension SDS PAGE nano-ESI- LCMS/MS shotgun proteomics. Results: The venom of T. albolabris contained the highest protein content of 11.1 mg/mL, followed by T. puniceus, T. insularis and T. purpureomaculatus venom with 10.7 mg/mL, 8.9 mg/mL and 5.54 mg/mL protein, respectively. In total, our venomic analysis identified 65 proteins belonging to 16 protein families in T. purpureomaculatus; 64 proteins belonging to 18 protein families in T. albolabris; 58 different proteins belonging to 14 protein families in T. puniceus; and 48 different proteins belonging to 14 protein familiesin T. insularis. Four major proteins identified in all venoms belonged to snake venom metalloproteinase, C-type lectin, snake venom serine protease, and phospholipase A2. There were 11 common proteins in all venoms, and T. puniceus venom has the highest number of unique proteins compared to the other three venoms. Cluster analysis of the proteins and venoms showed that T. puniceus venom has the most distinct venom composition. Conclusions: Overall, the results highlighted venom compositional variation of four Trimeresurus spp. from Indonesia. The venoms appear to be highly similar, comprising at least four protein families that correlate with venom's toxin properties and function. This study adds more information on venom variability among Trimeresurus species within the close geographic origin and may contribute to the development of optimum heterologous antivenom.(AU)

S- and P-type cobra venom cardiotoxins differ in their action on isolated rat heart

Background: The cardiovascular system is one of the first systems to be affected by snake toxins; but not many toxins exert a direct effect on the heart. Cobra venom cardiotoxins are among those few toxins that attack the heart. Although the two cardiotoxin types (S and P) differ in their central-loop structure, it is not known whether they differ in their effect on the mammalian heart. We compared the effects of S- and P-type cardiotoxins, CTÐ¥-1 and CTÐ¥-2, respectively, from the cobra Naja oxiana, on the isolated rat heart. Methods: An isolated rat heart perfused according to the Langendorff technique was used in this study to investigate the activity of cardiotoxins CTX-1 and CTX-2. The following parameters were registered: the left ventricular developed pressure, calculated as the difference between systolic and diastolic pressure in the left ventricle, the end-diastolic pressure, the heart rate, time to maximal end-diastolic pressure (heart contracture), and time to depression of the heart contraction. Results: Both cardiotoxins at the concentration of 5 µg/mL initially produce a slight increase in systolic intraventricular pressure, followed by its rapid decrease with a simultaneous increase in diastolic intraventricular pressure until reaching contracture. CTX-2 blocks cardiac contractions faster than CTX-1; in its presence the maximum diastolic pressure is reached faster and the magnitude of the developed contracture is higher. Conclusion: The P-type cardiotoxin CTX-2 more strongly impairs rat heart functional activity than the S-type cardiotoxin CTX-1, as expressed in its faster blockage of cardiac contractions as well as in more rapid development and greater magnitude of contracture in its presence.(AU)

First record of leucism in the polychromatic Amazon tree boa, Corallus hortulana (Serpentes, Boidae) of South America / Primeiro registro de leucismo em suaçuboia, Corallus hortulana (Serpentes, Boidae) uma espécie policromática da América do Sul

Snakes have a wide variety of color patterns that can be related to specific ecological and physiological functions. However, genetic mutations can lead to the appearance of anomalous color patterns, which can directly interfere with the fitness of individuals. Leucism is a chromatic anomaly characterized by the almost total absence of epidermal and dermal chromatophores that produce the color. Corallus hortulana is an arboreal snake with nocturnal habits, widely distributed throughout South America, with a wide range of color patterns, known as polychromatism. Here we report the first case of leucism in Corallus hortulana and discuss the potential ecological implications of this anomaly in this species.(AU)

As cobras possuem uma grande variedade de padrões de coloração que podem estar relacionadas a funções ecológicas e fisiológicas específicas. No entanto, mutações genéticas podem levar ao aparecimento de padrões de coloração anômalos que podem interferir diretamente na fitness do indivíduo. O leucismo é uma anomalia cromática caracterizada pela ausência quase total de cromatóforos epidérmicos e dérmicos que produzem a cor. Corallus hortulana é uma serpente arborícola de hábitos noturnos, amplamente distribuída pela América do Sul, com grande variação de padrões de cor, conhecida como policromatismo. Aqui nós relatamos o primeiro caso de leucismo em Corallus hortulana e discutimos as potenciais implicações ecológicas desta anomalia para a espécie.(AU)

Necrotic wound caused by jararaca (Bothrops jararaca) in a dog - hyperbaric oxygen therapy (HBTO)

Background: Snakebites are the main responsible for envenoming in dogs and the bothropic venom remains the mostcommon in Brazil, which can induce a necrotic skin wound. Hyperbaric oxygen therapy (HBOT) use 100% oxygen underhigh pressure and used to treat different wounds in human patients. To the authors’ knowledge, no reports regarding to usethe HBOT in skin wound caused by snakebite (Bothrops jararaca) are present in the literature. The present clinical caseaimed to describe the use of HBOT for the treatment of an extensive necrotic wound caused by jararaca snakebite in a dog.Case: A neutered 8-year-old mixed-breed dog, weighing 12 kg, was admitted with a 7-day history of extensive necroticwound was identified in the face and neck causing by a snakebite, and no sign of pain. The procedure of HBOT (singlesessions of 1.5 ATM, 45 min, repeated every 48 h, up to 12 sessions) was decided, and the complete blood cells, alanineaminotransferase, creatinine, creatine kinase, prothrombin time, activated partial thromboplastin time, wound clinicalevaluation were measured at the following time-points: 2nd, 5th, 10th, and 12th sessions. At the 5th session was identifiedleukopenia, neutropenia and lymphopenia. Wound re-epithelialization was initiated after the 5th session, and the completeepithelialization was identified at the 12th session of HBOT. During the HBOT no side effects were identified. Threemonths after the HBOT finished, the animal returned to the clinic and the clinical status evolved positively, and the woundwas completed healed.Discussion: This report described the treatment of an extensive necrotic skin wound caused by snakebite (Bothrops jararaca)in an 8-year-old, neutered, mixed-breed dog using the HBOT. The wound healing...

Necrotic wound caused by jararaca (Bothrops jararaca) in a dog - hyperbaric oxygen therapy (HBTO)

Background: Snakebites are the main responsible for envenoming in dogs and the bothropic venom remains the mostcommon in Brazil, which can induce a necrotic skin wound. Hyperbaric oxygen therapy (HBOT) use 100% oxygen underhigh pressure and used to treat different wounds in human patients. To the authors knowledge, no reports regarding to usethe HBOT in skin wound caused by snakebite (Bothrops jararaca) are present in the literature. The present clinical caseaimed to describe the use of HBOT for the treatment of an extensive necrotic wound caused by jararaca snakebite in a dog.Case: A neutered 8-year-old mixed-breed dog, weighing 12 kg, was admitted with a 7-day history of extensive necroticwound was identified in the face and neck causing by a snakebite, and no sign of pain. The procedure of HBOT (singlesessions of 1.5 ATM, 45 min, repeated every 48 h, up to 12 sessions) was decided, and the complete blood cells, alanineaminotransferase, creatinine, creatine kinase, prothrombin time, activated partial thromboplastin time, wound clinicalevaluation were measured at the following time-points: 2nd, 5th, 10th, and 12th sessions. At the 5th session was identifiedleukopenia, neutropenia and lymphopenia. Wound re-epithelialization was initiated after the 5th session, and the completeepithelialization was identified at the 12th session of HBOT. During the HBOT no side effects were identified. Threemonths after the HBOT finished, the animal returned to the clinic and the clinical status evolved positively, and the woundwas completed healed.Discussion: This report described the treatment of an extensive necrotic skin wound caused by snakebite (Bothrops jararaca)in an 8-year-old, neutered, mixed-breed dog using the HBOT. The wound healing...(AU)

A three-year Herpetofauna survey from one of the largest remnants of the Atlantic Rainforest Biome (Reserva Natural Vale)

Here we present a three-year survey of amphibian and reptile species registered in the Vale Natural Reserve (VNR), located in the north of Espírito Santo, southeastern Brazil. The VNR, along with the Sooretama Biological Reserve (SBR) and other surrounding areas, form a forest block that constitutes one of the largest remnants of continuous forest in the Atlantic Forest biome. We systematically sampled the herpetofauna community from 2015 to 2018, using the method of active search method in 27 plots of RAPELD distributed in the different types of vegetation present in the area. We recorded 39 species of amphibians belonging to the order Anura, distributed in seven families and 40 species of reptiles belonging to 20 families distributed in three orders: Crocodylia, Testudines and Squamata. The supplementation the samplings with those records from occasional encounters was important for the survey of the region's herpetofauna, mainly for reptiles. We added four species (two lizards, one amphisbaenid and one snake) to the known list for the VNR-SBR forest block: Micrablepharus maximiliani, Strobilurus torquatus, Amphisbaena alba and Tantilla sp. We demonstrated that VNR contains a high species richness of amphibians and reptiles, with a high number of anurans being endemic to the Atlantic Forest biome. The present species inventory provided the most current approximation of known the richness and composition of species of the existing herpetofauna at Vale Natural Reserve, since the period of the gathering of records is quite recent (2015-2018). Also, it brings the knowledge of some community parameters as species richness and composition not only for the whole area of the Vale Natural Reserve, but also for its different vegetation types, with no inclusion of environments outside this reserve. Furthermore, the presence of threatened species, the addition of four species to the current list, and the potential for new species to occur, reinforce the role of VNR as an important area for the protection of amphibian and reptile biodiversity in the Atlantic Forest.(AU)

Testicle histology of the Epicrates cenchria: a morphological and reproductive biology analysis / [Histologia dos testículos de Epicrates cenchria: uma análise morfológica e da biologia reprodutiva]

The lack of information about anatomy, physiology and reproductive biology in many snake species makes the understanding of these free-living animals' reproduction and reproductive biotechnics application in captivity difficult. The present study aims to evaluate the Epicrates cenchria's testicle morphology and correlate these findings with environmental aspects and reproductive biology. The testicles of five specimens of E. cenchria were histologically evaluated, and it was possible to observe seasonality in sperm production, with the presence of mature spermatozoa in the wettest and warmest periods of the year, as well as the highest testicular volume in these periods. Correlating these findings with that reported in the literature on copulation period presupposes a prenuptial (or associated) pattern in E. cenchria.

A falta de informações sobre anatomia, fisiologia e biologia reprodutiva em muitas espécies de serpentes impossibilita compreender melhor a reprodução desses animais em vida livre e aprimorar as biotécnicas reprodutivas nessas espécies em cativeiro. O presente trabalho tem como objetivo avaliar a morfologia dos testículos de Epicrates cenchria e correlacionar esses achados com aspectos ambientais e da biologia reprodutiva. Os testículos de cinco espécimes de E. cenchria foram avaliados histologicamente, sendo possível observar sazonalidade na produção espermática, com presença de espermatozoides maduros nos períodos mais chuvosos e quentes do ano, bem como o maior volume testicular nesses períodos. Correlacionando-se esses achados com o relatado em literatura sobre período de cópulas, pressupõe-se um padrão pré-nupcial (ou associado) em E. cenchria.

Biochemical and proteomic analyses of venom from a new pit viper, Protobothrops kelomohy

Background: A new pit viper, Protobothrops kelomohy, has been recently discovered in northern and northwestern Thailand. Envenoming by the other Protobothrops species across several Asian countries has been a serious health problem since their venom is highly hematotoxic. However, the management of P. kelomohy bites is required as no specific antivenom is available. This study aimed to investigate the biochemical properties and proteomes of P. kelomohy venom (PKV), including the cross-neutralization to its lethality with antivenoms available in Thailand. Methods: PKV was evaluated for its neutralizing capacity (ER50), lethality (LD50), procoagulant and hemorrhagic effects with three monovalent antivenoms (TAAV, DSAV, and CRAV) and one polyvalent (HPAV) hematotoxic antivenom. The enzymatic activities were examined in comparison with venoms of Trimeresurus albolabris (TAV), Daboia siamensis (DSV), Calloselasma rhodostoma (CRV). Molecular mass was separated on SDS-PAGE, then the specific proteins were determined by western blotting. The venom protein classification was analyzed using mass spectrometry-based proteomics. Results: Intravenous LD50 of PKV was 0.67 µg/g. ER50 of HPAV, DSAV and TAAV neutralize PKV at 1.02, 0.36 and 0.12 mg/mL, respectively. PKV exhibited procoagulant effect with a minimal coagulation dose of 12.5 ± 0.016 µg/mL and hemorrhagic effect with a minimal hemorrhagic dose of 1.20 ± 0.71 µg/mouse. HPAV was significantly effective in neutralizing procoagulant and hemorrhagic effects of PKV than those of TAAV, DSAV and CRAV. All enzymatic activities among four venoms exhibited significant differences. PKV proteome revealed eleven classes of putative snake venom proteins, predominantly metalloproteinase (40.85%), serine protease (29.93%), and phospholipase A2 (15.49%). Conclusions: Enzymatic activities of PKV are similarly related to other viperid venoms in this study by quantitatively hematotoxic properties. Three major venom toxins were responsible for coagulopathy in PKV envenomation. The antivenom HPAV was considered effective in neutralizing the lethality, procoagulant and hemorrhagic effects of PKV.(AU)