Development and characterization of nanobody against envenomation by Naja naja oxiana.

Snakebites are considered a significant health issue. Current antivenoms contain polyclonal antibodies, which vary in their specificity against different venom components. Development and characterization of next generation antivenoms including nanobodies against Naja naja oxiana was the main aim of this study. Crude venom was injected into the Sephadex G50 filtration gel chromatography column and then toxic fractions were obtained. Then the corresponding fraction was injected into the HPLC column and the toxic peaks were identified. N. naja oxiana venom was injected into a camel and specific nanobodies screening was performed against the toxic peak using phage display technique. The obtained results showed that among the 12 clones obtained, N24 nanobody was capable of neutralizing P1, the most toxic peak obtained from HPLC chromatography. The molecular weight of P1 was measured with a mass spectrometer and was found to be about seven kDa. The results of the neutralization test of crude N. naja oxiana venom with N24 nanobody showed that 250 µg of recombinant nanobody could neutralize the toxic effects of 20 µg equivalent to LD50 × 10 of crude venom in mice. The findings indicate the potential of the developed nanobody to serve as a novel antivenom therapy.

Compartment syndrome of arm secondary to snake bite on hand: a case report.

Introduction: Snake bites pose a significant common public health concern, with more prevalence in rural areas. Compartment syndrome (CS) is one of the rare and severe manifestations of snake bite wherein venom-induced swelling within a closed anatomical compartment leads to increased pressure, which may result in ischemic damage to nerves and muscle. Antisnake venom and prompt fasciotomy is recommended for management of CS secondary to snake bite. Case details: Here, the authors report a case of 47-year-old female with Green Pit Viper bite on the left hand. Upon arrival to hospital, initial resuscitation measures were initiated. Six hours following the bite, there was severe pain on passive stretch and paresthesia. Ten vials of antisnake venom administration along with fasciotomy of hand and arm resulted in notable alleviation of pain and swelling. Eighteen pints of blood was transfused for coagulopathy and low hemoglobin. After continued care of wound and intensive physiotherapy, functional limb could be achieved. Discussion: Snake bite envenomation is one of the biggest hidden health crises with case fatality rate of 7.8% in the southern plains of Nepal. As in our case, snake bites commonly affect upper extremities, accounting for around two third of all cases. CS must be differentiated from acute swelling, which sometimes may be difficult. Surgical decompression is indicated in presence of signs and symptoms of CS, in case of resource limited setting. Conclusion: Multidisciplinary and prompt management with initial resuscitation, ASV administration, fasciotomy, and rehabilitative measures can save both life and limb in such cases.

Cryptosporidium spp. in captive snakes from 26 provinces in China: Prevalence, molecular characterization, and symptoms.

Snakes are sometimes regarded as pets and are used in traditional Chinese medicine. Cryptosporidium spp. are frequently identified in snakes, representing an important pathogen and causing gastrointestinal diseases. Current data indicate that risk factors for infection and patterns of clinical symptom presentation may differ among Cryptosporidium spp. To better understand the infection status by Cryptosporidium spp., fecal samples were collected from 603 asymptomatic and 147 symptomatic snakes in 26 provinces of China. These samples came from Elaphe guttata, Elaphe obsoleta, Pituophis melanoleucus, Thamnophis sirtalis, Lampropeltis getulus, and Heterodon nasicus. The partial small subunit (SSU) rRNA gene was amplified using nested polymerase chain reaction (PCR) to investigate the infection rate of Cryptosporidium spp., and to assess evolutionary relationships and genetic characterization. A prevalence of 20% was recorded in asymptomatic snakes, with age identified as a significant risk factor. In contrast, 70% of symptomatic snakes were positive for Cryptosporidium spp., with Cryptosporidium serpentis and Cryptosporidium varanii (syn. C. saurophilum). Further analysis revealed a potential association between C. serpentis and regurgitation, and C. varanii and diarrhea, while neither species was linked to flatulence. To our knowledge, this is the first study to report Cryptosporidium spp. and associated clinical signs in symptomatic snakes in China. This study aims to enhance the understanding of Cryptosporidium infections, risk factors, and clinical manifestations in snakes, providing data crucial for the control and prevention of cryptosporidiosis.

Title: Cryptosporidium spp. chez les serpents captifs de 26 provinces de Chine : prévalence, caractérisation moléculaire et symptômes. Abstract: Les serpents sont parfois considérés comme animaux de compagnie et sont utilisés en médecine traditionnelle chinoise. Des Cryptosporidium spp. sont fréquemment identifiés chez les serpents, ont un rôle d'agent pathogène important et provoquent des maladies gastro-intestinales. Les données actuelles indiquent que les facteurs de risque d'infection et les schémas de présentation des symptômes cliniques peuvent varier en fonction des espèces de Cryptosporidium. Pour mieux comprendre l'état d'infection par Cryptosporidium spp., des échantillons fécaux ont été collectés auprès de 603 serpents asymptomatiques et 147 serpents symptomatiques dans 26 provinces de Chine. Ces échantillons provenaient d'Elaphe guttata, Elaphe obsoleta, Pituophis melanoleucus, Thamnophis sirtalis, Lampropeltis getulus et Heterodon nasicus. Le gène de l'ARNr de la petite sous-unité partielle (SSU) a été amplifié à l'aide d'une réaction en chaîne par polymérase (PCR) imbriquée pour étudier le taux d'infection par Cryptosporidium spp. et évaluer les relations évolutives et la caractérisation génétique. Une prévalence de 20 % a été trouvée chez les serpents asymptomatiques, l'âge étant identifié comme un facteur de risque important. En revanche, 70 % des serpents symptomatiques étaient positifs à Cryptosporidium spp. avec Cryptosporidium serpentis et Cryptosporidium varanii (syn. C. saurophilum). Une analyse plus approfondie a révélé une association potentielle entre C. serpentis et la régurgitation, et C. varanii et la diarrhée, alors qu'aucune des deux espèces n'était liée aux flatulences. À notre connaissance, il s'agit ici de la première étude à signaler la présence de Cryptosporidium spp. et les signes cliniques associés chez des serpents symptomatiques en Chine. Cette étude vise à améliorer la compréhension des infections à Cryptosporidium, des facteurs de risque et des manifestations cliniques chez les serpents, en fournissant des données cruciales pour le contrôle et la prévention de la cryptosporidiose.

Exponential PID controller for effective load frequency regulation of electric power systems.

Load frequency regulation (LFR) is an indispensable scheme in planning electrical power production to provide consumers with stable, reliable and uninterrupted power. In the face of complicated power system (PS) structures with increasing and intricate power demand, new controllers that offer not only good performance, but also easy commissioning in practice are required. To this end, this research introduces an exponential PID (EXP-PID) controller as a new control scheme to ameliorate the LFR performance of PSs. This controller is simple to design and has a nonlinear feature inherited from two tunable exponential functions, which are placed in front of the PID controller and act on the error signal and its time derivative individually. To achieve the utmost performance, the EXP-PID controller's parameters are procured by a corrected variant of the snake optimizer (co-SO). To validate the proposed control scheme, various single-/multi-area single-/multi-source PSs favored in the area are considered as test benches. A thorough comparison with the state-of-the-art approaches is performed to disclose the true efficacy of our proposal. Among the rivals, co-SO tuned EXP-PID controller, despite its simplicity, is found to render credible and promising performance in mitigating frequency and tie-line power deviations effectively.

Engineering of pH-dependent antigen binding properties for toxin-targeting IgG1 antibodies using light-chain shuffling.

Immunoglobulin G (IgG) antibodies that bind their cognate antigen in a pH-dependent manner (acid-switched antibodies) can release their bound antigen for degradation in the acidic environment of endosomes, while the IgGs are rescued by the neonatal Fc receptor (FcRn). Thus, such IgGs can neutralize multiple antigens over time and therefore be used at lower doses than their non-pH-responsive counterparts. Here, we show that light-chain shuffling combined with phage display technology can be used to discover IgG1 antibodies with increased pH-dependent antigen binding properties, using the snake venom toxins, myotoxin II and α-cobratoxin, as examples. We reveal differences in how the selected IgG1s engage their antigens and human FcRn and show how these differences translate into distinct cellular handling properties related to their pH-dependent antigen binding phenotypes and Fc-engineering for improved FcRn binding. Our study showcases the complexity of engineering pH-dependent antigen binding IgG1s and demonstrates the effects on cellular antibody-antigen recycling.

Novel GPIb-independent platelet aggregation induced by botrocetin: Implications for diagnosis and antithrombotic therapy.

BACKGROUND: Snake venom botrocetin facilitates von Willebrand factor (VWF) binding to platelet GPIbα and has been widely used for the diagnosis of von Willebrand diseases and GPIb-related disorders. Botrocetin is also commonly employed for the development/characterization of antithrombotics targeting the GPIb-VWF axis. OBJECTIVE: To explore the alternative receptor(s)/mechanisms participate in botrocetin-induced platelet aggregation. METHODS: The effects of botrocetin on platelet aggregation were examined using platelets from wild-type, VWF and fibrinogen-deficient, GPIbα-deficient, IL4Rα/GPIbα-transgenic and αIIbß3-deficient mice, Bernard-Soulier syndrome (BSS) and healthy human samples. Platelet-fibrinogen and platelet-VWF interaction were measured using flow cytometry. GPIbα-VWF binding was evaluated utilizing ELISA. Botrocetin-αIIbß3 and botrocetin-GPIbα interactions were measured using ELISA and fluorescence anisotropy assays. Heparinized whole blood from healthy donors was examined for thrombus formation and growth in a perfusion chamber. RESULTS: Botrocetin could induce aggregation of platelets from a BSS patient and GPIbα-deficient mice as well as platelets lacking the N-terminal extracellular domain of GPIbα. Botrocetin could interact with αIIbß3 and facilitated αIIbß3-VWF interaction independent of GPIb. Botrocetin competitively bound to the ligand-binding domain of activated rather than resting αIIbß3. Although botrocetin-induced platelet aggregation requires VWF, strikingly, in the absence of VWF, botrocetin blocked fibrinogen and other ligand binding to αIIbß3, and inhibited platelet aggregation and thrombus formation. Consistently, recombinant botrocetin defective in VWF binding inhibited αIIbß3 and GPIb-mediated platelet aggregation, spreading and thrombus formation. CONCLUSION: Our study provides insights into avoiding the misdiagnosis of GPIb-related disorders and developing botrocetin mutants as potential new antithrombotics that may simultaneously target both αIIbß3 and GPIbα.

Paraspecific neutralization capacity of polyvalent snake antivenom against Montivipera wagneri venom.

PURPOSE: This study aims to measure the paraspecific neutralization capacity of nationally produced HSGM polyvalent snake antivenom (HSGM-PSAV), produced using Macrovipera lebetina obtusa, Montivipera xanthina, and Vipera ammodytes montandoni venom, against the lethal effect of the venom of Montivipera wagneri, which is endemic to the Eastern Black Sea and Eastern Anatolia regions of Turkey. METHODS: The neutralization capacity of HSGM-PSAV against the lethal effect of M. wagneri venom was studied using the potency determination testing method specified in the Turkish and European Pharmacopoeia. Lethal dose 50 (LD50) values of the venoms used in immunization, M. wagneri venom in mice, and effective dose 50 (ED50) values of HSGM-PSAV against four types of venoms were calculated using two-fold dilutions. RESULTS: HSGM-PSAV neutralized the lethal effect of M. wagneri venom in mice. The ED50 of the HSGM-PSAV against M. wagneri venom was calculated as 304.42 LD50/mL. CONCLUSION: As a result of this in-vivo study, it was determined that HSGM-PSAV neutralized M.wagneri venom above the antivenom neutralization capacity threshold values (≥50 LD50/mL) specified in the Turkish and European Pharmacopoeia. This result is important preclinical data regarding the usability of HSGM-PSAV in the treatment of poisoning due to M. wagneri bites.

The annual ovarian cycle in Northern pit vipers (Bothrops atrox) using serum steroids and ultrasound of the female reproductive tract.

Knowledge on hormonal regulation of reproductive cycles in viperid snakes is still incipient, especially when it comes to females and tropical species. There is an urgent need to understand the reproduction of venomous snakes to improve assisted reproduction techniques and optimize the maintenance of these animals in captivity. With this in mind, we monitored Northern pit viper females year-round throughout different seasons via serum levels of progesterone (P4) and estradiol (E2) in conjunction with ultrasound examinations. Ovarian follicles were classified according to their size and stage of vitellogenesis in F-I and F-II (non-vitellogenic phase) or in F-III and F-IV (vitellogenic phase). During autumn and winter, five adult males were rotated among these females for reproductive pairing, which resulted in 17 copulations and 2 pregnancies in the first year and 12 copulations and 5 pregnancies in the second year. Then, we assessed changes in P4 and E2 levels according to seasons, predominant ovarian structures and the presence of embryos or eggs in the oviduct. Our findings showed high levels of E2 when a greater number of vitellogenic follicles were detected, indicating a possible influence of E2 on vitellogenesis and higher levels of P4 whenever eggs and embryos were visualized in the oviduct, implying its role in maintaining pregnancy. Descriptive analysis of the vipers' ovarian cycles revealed a greater number of vitellogenic follicles during winter, probably as a result of increases in E2; whereas pregnancies occurred predominantly in spring, under the influence of P4. The use of ultrasound images, as a minimally invasive methodology, associated with serum steroid levels has proven to be an efficient approach in the reproductive monitoring of Northern pit vipers in vivo. In addition, these data suggest that female pit vipers under human care display a seasonal reproductive cycle, despite earlier studies involving captive males of the species indicating a lack of seasonality in sperm production and quality.

New perspective for pathomechanism and clinical applications of animal toxins: Programmed cell death.

Various animal toxins pose a significant threat to human safety, necessitating urgent attention to their treatment and research. The clinical potential of programmed cell death (PCD) is widely regarded as a target for envenomation, given its crucial role in regulating physiological and pathophysiological processes. Current research on animal toxins examines their specific components in pathomechanisms and injuries, as well as their clinical applications. This review explores the relationship between various toxins and several types of PCD, such as apoptosis, necroptosis, autophagy, ferroptosis, and pyroptosis, to provide a reference for future understanding of the pathophysiology of toxins and the development of their potential clinical value.

Evaluation of the International Society on Thrombosis and Haemostasis definition of major bleeding in Arizona rattlesnake bites.

INTRODUCTION: In 2023, a group of experts proposed that a definition of major bleeding in pharmaceutically anticoagulated patients be used in all snakebite trials. This includes bleeding that results in death, is life-threatening, causes chronic sequelae, or consumes major healthcare resources, including bleeding into a major area or hemoglobin concentration decrease ≥20 g/L. We hypothesized that a decline in hemoglobin concentration ≥20 g/L is common but rarely clinically significant in our population of Arizona rattlesnake bite patients. METHODS: Poison center records of rattlesnake bites in humans from 2018 through 2022 were retrospectively reviewed and assessed for major bleeding by the above criteria. RESULTS: Four hundred and eighty-one patients met the inclusion criteria, of whom 265 (55.1%) had a hemoglobin concentration decrease ≥20 g/L. No patients died, and there was no evidence of bleeding into a critical organ. Three patients (1.1%) received blood transfusions. A decrease in hemoglobin concentration ≥20 g/L was 100% sensitive for identifying the major bleeding-associated outcomes; however, specificity was only 45.2%. Measures of healthcare utilization and chronic sequelae were somewhat higher in patients with a decrease in hemoglobin concentration ≥20 g/L. DISCUSSION: Laboratory manifestations of hemotoxicity were common in this population, but hemorrhage was rare. While over half of patients met the major bleeding criterion of a decline in hemoglobin concentration ≥20 g/L, only 1.1% had bleeding that was potentially life-threatening as measured by receipt of a red blood cell transfusion. None died or had bleeding into a critical area. While nonspecific for major bleeding, a drop in hemoglobin concentration correlated with worse envenomation severity: these patients received more vials of antivenom, had a higher medical bill, a longer hospital stay, and were less likely to report full recovery at 90 days. CONCLUSIONS: A decrease in hemoglobin concentration ≥20 g/L should not be used as evidence of major bleeding for Arizona rattlesnake envenomation studies, but it may have a role as an indirect marker of envenomation severity.

Behavior and Activity Patterns of the Critically Endangered Mangshan Pit Viper (Protobothrops mangshanensis) Determined Using Remote Monitoring.

This study focuses on understanding the behavior and activity patterns of the critically endangered Protobothrops mangshanensis in China in order to better provide scientific data for upcoming artificial breeding and propagation efforts. We conducted a long-term observation of 15 Mangshan pit vipers at different sites in Hunan Province during the summer and autumn of 2021. Our methods involved analyzing the influence of environmental factors such as temperature, relative humidity, and light condition on the snakes' day and night activity and behaviors. The results revealed that the wild behaviors of Protobothrops mangshanensis include resting, sunbathing, crawling, and exploring, with distinct rhythms in their diel behavior. The snakes' diel activity exhibits three peak periods which may be related to food activity and sunbathing. This study also highlights the complex interplay of environmental factors on the activity of Protobothrops mangshanensis. Relative humidity was identified as a critical factor accounting for the difference in activity between observation groups. There was little inter-individual variation among the 15 Protobothrops mangshanensis, even though these snakes used terrestrial and arboreal habitats under different environmental conditions. These findings enhance our understanding of Protobothrops mangshanensis behavior and provide a basis for effective conservation measures for this rare and critically endangered species.

A case report of mis-snaken identity: When misdiagnosis really bites.

When patients present with an unknown puncture wound, emergency physicians need to consider regional hazards, in addition to standard mechanical injury etiologies. In the Southwestern United States, one such hazard is the rattlesnake. In this report, we present a case in which a rattlesnake envenomation was not considered as a possible cause for a puncture wound of unknown origin, which resulted in an envenomation left untreated for 7 days. A full dry bite observation period of 12 h with serial physical exams and laboratory analysis with guidance from the region poison control center might have led to earlier recognition of an envenomation and antivenom administration. A male patient in his late 70's felt a painon his right ankle while in his backyard in southern Arizona. He did not see the cause and assumed he had sustained an insect bite. He went to the ED that day with minor pain and swelling and was discharged home. One week later, he re-presented severely anemic with edema and ecchymosis to the entire right lower extremity that developed over several days after his first ED visit. He was admitted for antivenom and blood transfusion and discharged on hospital day three. For as long as humans continue to interact with the natural world, venomous creature encounters are going to continue to happen. Rattlesnake envenomation should be included in a physician's differential diagnosis even if one is not witnessed, especially in regions with high rattlesnake activity. In addition to assessing for other potential causes of undifferentiated puncture wounds, serial physical examinations and laboratory testing (with guidance of the regional poison center) are necessary to rule out rattlesnake envenomation.

Retrospective Detection of Ophidiomyces ophidiicola from Snake Moults Collected in Bieszczady Mountains, Poland.

Ophidiomyces ophidiicola, the causative agent of ophidiomycosis, poses a potential threat to wild snakes worldwide. This study aimed to retrospectively investigate the prevalence of O. ophidiicola in archived snake moults collected from the San River Valley in the Bieszczady Mountains, Poland, from 2010 to 2012. Using qPCR for O. ophidiicola detection and conventional PCR for clade characterisation, we analysed 58 moults and one road-killed specimen of Zamenis longissimus and Natrix natrix. A novel combination of primers (ITS2L) was used to simultaneously confirm SYBR Green-based qPCR results and perform genotyping. O. ophidiicola has been detected from two Z. longissimus and one N. natrix specimens. The identified clade (I-B) is consistent with those found in wild snakes of eastern Europe and San River Valley, indicating that O. ophidiicola has been present in this region for at least a decade. This study underscores the value of historical samples in understanding the long-term presence of pathogens and highlights the potential role of environmental reservoirs in the persistence of O. ophidiicola. Our findings are crucial for informing conservation strategies for the endangered Aesculapian snake populations in Poland, emphasising the need for ongoing monitoring and habitat management to mitigate the potential impact of ophidiomycosis.

Small Structural Differences in Proline-Rich Decapeptides Have Specific Effects on Oxidative Stress-Induced Neurotoxicity and L-Arginine Generation by Arginosuccinate Synthase.

INTRODUCTION: The proline-rich decapeptide 10c (Bj-PRO-10c; ENWPHPQIPP) from the Bothrops jararaca snake modulates argininosuccinate synthetase (AsS) activity to stimulate L-arginine metabolite production and neuroprotection in the SH-SY5Y cell line. The relationships between structure, interactions with AsS, and neuroprotection are little known. We evaluated the neuroprotective effects of Bj-PRO-10c and three other PROs (Bn-PRO-10a, Bn-PRO-10c > Bn-PRO-10a-MK > Bn-PRO-10a. The structure of PROs and their correlations with enzyme activity revealed that histidine (H5) and glutamine (Q7) in Bj-PRO-10c potentiated their affinity for AsS. CONCLUSIONS: Our investigation provides the first insights into the structure and molecular interactions of PROs with AsS, which could possibly further their neuropharmacological applications.

Venom variation among the three subspecies of the North African mountain viper Vipera monticola (Saint-Girons 1954).

The North African mountain viper (Vipera monticola) is a medically relevant venomous snake distributed in Morocco, Algeria, and Tunisia. Three subspecies of V. monticola, exhibiting differences in morphotypes and dietary regimes, are currently recognised: V. m. monticola, V. m. atlantica, and V. m. saintgironsi. Through the application of snake venomics, we analysed the venoms of specimens of Moroccan origin belonging to each of the three subspecies. Snake venom metalloproteinase (svMP), snake venom serine protease (svSP), C-type lectin and C-type lectin-related proteins (CTL), and phospholipase A2 (PLA2) were predominant, with PLA2 being the most abundant toxin family overall. Disintegrins (DI) and cysteine-rich secretory proteins (CRISP) were exclusive to V. m. monticola and V. m. atlantica, while l-amino-acid oxidases (LAAO) were only found in V. m. saintgironsi. The differences detected in the venom profiles, as well as in presence/absence and relative abundances of toxin families, indicate the occurrence of intraspecific venom variation within V. monticola. The identified patterns of venom similarity between subspecies seem to align more with their phylogenetic relationships than with the reported differences in their feeding habits.

A new species of the genus Hebius (Squamata, Natricidae) from Yunnan, China.

A new species of the genus Hebius Thompson, 1913 is described from Yingjiang County, Dehong Dai and Jingpo Autonomous Prefecture, Yunnan Province, China, based on molecular and morphological evidence. It can be distinguished from its congeners by the following set of characters: (1) dorsal scale rows 19-17-17, feebly keeled; (2) ventrals 146-151; (3) nasal complete, nostril in the middle of the nasal; (4) supralabials 9, the fourth to sixth in contact with the eye; (5) infralabials 10-11, the first 5 touching the first pair of chin shields; (6) preoculars 2; (7) postoculars 3; (8) temporals 3, arranged in two rows (1+2); (9) maxillary teeth 31, the last 4 slightly enlarged, without diastema; (10) tail comparatively long, TAL/TL ratio 0.334 in the male; (11) dorsolateral series of irregular orange or ochre yellow blotches, extending from the neck to the posterior part of the tail; and (12) venter pale orange, tips of ventrals with subrectangular black blotches. All Hebius specimens were strongly recovered as monophyletic, in which Hebiustaronensis (Smith, 1940) and Hebiusvenningi (Wall, 1910) were monophyletic as sister to the Yingjiang County specimens. According to the p-distance of cytochrome b, the new species differs from its congeners by 9.7-15.4%.

Effects of Freeze-Thaw Pretreatment Combined with Hot Air on Snake Gourd (Trichosanthes anguina L.).

Snake gourd is a seasonal vegetable with a high water content and medicinal value, but the short harvest period limits the large-scale application of snake gourd. Therefore, the effects of freeze-thaw pretreatment (FT) combined with hot air (HD) on the drying characteristics, active ingredients and bioactivities of snake gourd were investigated. The results showed that FT pretreatment reduced browning and shortened the drying time by 44%; the Page model was the best fit for describing the drying process. The polysaccharide contents (21.70% in alcoholic extract (TG1) and 44.34% in water extract (TG2)) and total phenol contents (1.81% in TG1 and 0.88% in TG2) of snake gourd pretreated by FT-HD were higher than those of snake gourd pretreated by the corresponding HD treatment. The FT pretreatment decreased the molecular weight of snake gourd polysaccharides and increased the molar ratio of glucose. The extracts pretreated by FT-HD showed greater chemical, cellular antioxidant capacity and α-amylase and α-glucosidase inhibition than those pretreated by HD. FT-HD can be recommended for achieving a short drying time and high quality of snake gourd and can be used for the drying of other fruits and vegetables.

Visual-Aided Obstacle Climbing by Modular Snake Robot.

Snake robots, also known as apodal robots, are among the most common and versatile modular robots. Primarily due to their ability to move in different patterns, they can evolve in scenarios with several constraints, some of them hardly accessible to other robot configurations. This paper deals with a specific environment constraint where the robot needs to climb a prismatic obstacle, similar to a step. The objective is to carry out simulations of this function, before implementing it in the physical model. To this end, we propose two different algorithms, parameterized by the obstacle dimensions determined by image processing, and both are evaluated in simulated experiments. The results show that both algorithms are viable for testing in real robots, although more complex scenarios still need to be further studied.

Identification of purinergic system components in the venom of Bothrops mattogrossensis and the inhibitory effect of specioside extracted from Tabebuia aurea.

Snake bites are a severe problem in the countryside of Brazil and are usually attributed to snakes of the genera Bothrops, Crotalus, and Lachesis. Snake venom can release ectoenzymes and nucleotidases that modulate the purinergic system. In addition to serum therapy against snake poisoning, medicinal plants with anti-inflammatory activities, such as Tabebuia aurea, is empirically applied in accidents that occur in difficult-to-access areas. This study aimed was to verify the presence and activity of nucleotidases in the crude venom of Bothrops mattogrossensis (BmtV) in vitro and characterize the modulation of purinergic components, myeloid differentiation, and inflammatory/oxidative stress markers by BmtV in vivo and in vitro. Moreover, our study assessed the inhibitory activities of specioside, an iridoid isolated from Tabebuia aurea, against the effects of BmtV. Proteomic analysis of venom content and nucleotidase activity confirm the presence of ectonucleotidase-like enzymes in BmtV. In in vivo experiments, BmtV altered purinergic component expression (P2X7 receptor, CD39 and CD73), increased neutrophil numbers in peripheral blood, and elevated oxidative stress/inflammatory parameters such as lipid peroxidation and myeloperoxidase activity. BmtV also decreased viability and increased spreading index and phagocytic activity on macrophages. Specioside inhibited nucleotidase activity, restored neutrophil numbers, and mediate the oxidative/inflammatory effects produced by BmtV. We highlight the effects produced by BmtV in purinergic system components, myeloid differentiation, and inflammatory/oxidative stress parameters, while specioside reduced the main BmtV-dependent effects.

Parturition of a rear-fanged rainbow water snake (Enhydrisenhydris) involved in snakebite and effects of its envenoming in Nepal.

Based on a specimen preserved in the snakebite treatment center in eastern Nepal, this study aims to analyse brief life history (i.e., litter size, parturition date, habitat preference) of Enhydris enhydris, effects of its envenoming, and anthropogenic threat on its populations. One euthanized gravid female E. enhydris collected alive from eastern Nepal by a snakebite victim was examined. The gravid female gave birth to 23 litters on July 11, 2012. This parturition suggested high reproductive potential. Its bite to a man walking on the road caused no ill-effects. However, the use of tourniquet as a part of prehospital care might be detrimental or be obstacle for in-hospital care of snakebite. The conflicts between E. enhydris and humans at roads and human-activity areas are inevitable across the distribution ranges of this species. The continued anthropogenic impact can threaten its populations. This study finding can be a basis for assessing conservation status and options for its conservation as well as prehospital care and prevention of its bites.