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Sample records for vipera lebetina snake

  1. [Influence of electromagnetic radiation on toxicity of Vipera lebetina obtusa venom].

    Science.gov (United States)

    Abiev, G A; Babaev, E I; Topchieva, Sh A; Chumburidze, T B; Nemsitsveridze, N G

    2009-11-01

    The aim of the article was to study the effect of electromagnetic radiation on toxicity of Vipera lebetina obtusa venom. It was found that mice intoxicated with snake venom, with moderate to high exposure to electromagnetic radiation and mice intoxicated with venom, which had not been exposed to the radiation showed the same symptoms of intoxication and death. At the same time, the longevity of mice intoxicated with venom exposed to electromagnetic radiation was higher. The longevity of mice in control group was 25+/-5 min. The longevity of mice intoxicated with exposed to electromagnetic radiation snake venom was from 29 to 60 min. The research showed that the longevity of mice intoxicated with snake venom rose with the level of electromagnetic radiation intensity the snake was exposed to. Accordingly, snake venom, with exposure to high intensity electromagnetic radiation is less toxic.

  2. Interactions of PLA2-s from Vipera lebetina, Vipera berus berus and Naja naja oxiana Venom with Platelets, Bacterial and Cancer Cells

    Science.gov (United States)

    Samel, Mari; Vija, Heiki; Kurvet, Imbi; Künnis-Beres, Kai; Trummal, Katrin; Subbi, Juhan; Kahru, Anne; Siigur, Jüri

    2013-01-01

    Secretory phospholipasesA2 (sPLA2s) form a large family of structurally related enzymes widespread in nature. Herein, we studied the inhibitory effects of sPLA2s from Vipera lebetina (VLPLA2), Vipera berus berus (VBBPLA2), and Naja naja oxiana (NNOPLA2) venoms on (i) human platelets, (ii) four different bacterial strains (gram-negative Escherichia coli and Vibrio fischeri; gram-positive Staphylococcus aureus and Bacillus subtilis) and (iii) five types of cancer cells (PC-3, LNCaP, MCF-7, K-562 and B16-F10) in vitro. sPLA2s inhibited collagen-induced platelet aggregation: VBBPLA2 IC50 = 0.054, VLPLA2 IC50 = 0.072, NNOPLA2 IC50 = 0.814 μM. p-Bromophenacylbromide-inhibited sPLA2 had no inhibitory action on platelets. 36.17 μM VBBPLA2 completely inhibited the growth of gram-positive Bacillus subtilis whereas no growth inhibition was observed towards gram-negative Escherichia coli. The inhibitory action of sPLA2s (~0.7 μM and ~7 μM) towards cancer cells depended on both venom and cell type. VBBPLA2 (7.2 μM) inhibited significantly the viability of K-562 cells and the cell death appeared apoptotic. The sPLA2s exhibited no inhibitory effect towards LNCaP cells and some effect (8%–20%) towards other cells. Thus, already sub-μM concentrations of sPLA2s inhibited collagen-induced platelet aggregation and from the current suite of studied svPLA2s and test cells, VBBPLA2 was the most growth inhibitory towards Bacillus subtilis and K-562 cells. PMID:23348053

  3. Interactions of PLA2-s from Vipera lebetina, Vipera berus berus and Naja naja oxiana Venom with Platelets, Bacterial and Cancer Cells

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    Jüri Siigur

    2013-01-01

    Full Text Available Secretory phospholipasesA2 (sPLA2s form a large family of structurally related enzymes widespread in nature. Herein, we studied the inhibitory effects of sPLA2s from Vipera lebetina (VLPLA2, Vipera berus berus (VBBPLA2, and Naja naja oxiana (NNOPLA2 venoms on (i human platelets, (ii four different bacterial strains (gram-negative Escherichia coli and Vibrio fischeri; gram-positive Staphylococcus aureus and Bacillus subtilis and (iii five types of cancer cells (PC-3, LNCaP, MCF-7, K-562 and B16-F10 in vitro. sPLA2s inhibited collagen-induced platelet aggregation: VBBPLA2 IC50 = 0.054, VLPLA2 IC50 = 0.072, NNOPLA2 IC50 = 0.814 μM. p-Bromophenacylbromide-inhibited sPLA2 had no inhibitory action on platelets. 36.17 μM VBBPLA2 completely inhibited the growth of gram-positive Bacillus subtilis whereas no growth inhibition was observed towards gram-negative Escherichia coli. The inhibitory action of sPLA2s (~0.7 μM and ~7 μM towards cancer cells depended on both venom and cell type. VBBPLA2 (7.2 μM inhibited significantly the viability of K-562 cells and the cell death appeared apoptotic. The sPLA2s exhibited no inhibitory effect towards LNCaP cells and some effect (8%–20% towards other cells. Thus, already sub-μM concentrations of sPLA2s inhibited collagen-induced platelet aggregation and from the current suite of studied svPLA2s and test cells, VBBPLA2 was the most growth inhibitory towards Bacillus subtilis and K-562 cells.

  4. Snakes of Medical Significance in India: The First Reported Case of Envenoming by the Levantine Viper (Macrovipera lebetina)

    National Research Council Canada - National Science Library

    Col. Lekh R. Sharma; Lt. Col. Vivek Lal; Ian D. Simpson

    2008-01-01

    ... (Macrovipera lebetina) in India. This snake is found in India in the mountainous regions of Jammu and Kashmir and is capable of causing necrosis and hemostatic manifestations, as seen in the case reported here...

  5. Unusual neurotoxic envenomations by Vipera aspis aspis snakes in France.

    Science.gov (United States)

    de Haro, L; Robbe-Vincent, A; Saliou, B; Valli, M; Bon, C; Choumet, V

    2002-03-01

    Vipera aspis aspis (V.a.a.) is the most dangerous poisonous snake in South-Eastern France. The clinical symptoms observed after V.a.a. envenomations involve mostly local signs (pain, edema) associated in the more severe cases with systemic symptoms (gastro-intestinal and cardiovascular manifestations). Since 1992, several unusual cases of moderate and severe 'neurotoxic' envenomations by V.a.a. snakes have been reported in a very localized area in South-Eastern France. Most of the human patients mainly suffered neurological signs owing to cephalic muscle paralysis. Drowsiness and dyspnea were observed for the most severe cases. Envenomed animals suffered respiratory distress and paralysis. The local signs were never as severe as observed after envenomations by vipers in other French regions. Human patients with moderate or severe clinical features received two intravenous injections of Viperfav antivenom, the first dose inducing the decrease of the neurological signs and the second reducing significantly the edema. Neurotoxic components immunologically cross-reacting with toxins from V. ammodytes ammodytes venom from Eastern Europe were detected in the blood of all patients suffering neurological symptoms after a V.a.a. bite. The protective efficacy of various antivenoms was evaluated in mice. The existence of geographical variations in the composition of V.a.a. venom emphasizes on the use of polyvalent antivenom in the treatment of viper envenomations in France.

  6. Variation in yield and lethality of venoms from Iranian snakes.

    Science.gov (United States)

    Latifi, M

    1984-01-01

    The dangerous venomous terrestrial snakes of Iran belong to three groups: the Elapidae (cobras); the Viperinae (true vipers); the Crotalinae (pit vipers). Geographical distribution of each species was determined. Studies on the venoms extracted from the following Iranian snakes, Oxus cobra, Naja naja oxiana, Levantine viper (Afyi), Vipera lebetina, Carpet viper, Echis carinatus, Persian horned viper, Pseudocerastes persicus, Latifii viper, Vipera latifii, Mountain viper, Vipera xanthina and Caucasus pit viper (Agkistrodon halys), indicated that the yield of venom varies in each species. Venoms were compared for their lethality (i.v. LD50 in mice) and their rate of production. The antigenic components of the venoms were compared with their antisera by gel diffusion tests. To obtain the best results from antivenom treatment, the serum should be made against the venom of the local population of snakes or, at least, the commercial antivenom should be controlled for potency by testing with local reference venom.

  7. Snake (Vipera berus) bite: The cause of severe anaphylactic shock and hepatocellular injury

    National Research Council Canada - National Science Library

    Pałgan, K; Kuźmiński, A; Janik, A; Gotz-Żbikowska, M; Bartuzi, Z

    2015-01-01

    Vipera berus bites lead to a variety of clinical manifestations. Local swelling, coagulopathy, nephrotoxicity, cardiac effects and myotoxicity are known to be associated with envenoming by a viper bite...

  8. Fat is sexy for females but not males: the influence of body reserves on reproduction in snakes (Vipera aspis).

    Science.gov (United States)

    Aubret, Fabien; Bonnet, Xavier; Shine, Richard; Lourdais, Olivier

    2002-09-01

    Reproduction is energetically expensive for both sexes, but the magnitude of expenditure and its relationship to reproductive success differ fundamentally between males and females. Males allocate relatively little to gamete production and, thus, can reproduce successfully with only minor energy investment. In contrast, females of many species experience high fecundity-independent costs of reproduction (such as migration to nesting sites), so they need to amass substantial energy reserves before initiating reproductive activity. Thus, we expect that the relationship between energy reserves and the intensity of reproductive behavior involves a threshold effect in females, but a gradual (or no) effect in males. We tested this prediction using captive vipers (Vipera aspis), dividing both males and females into groups of high versus low body condition. Snakes from each group were placed together and observed for reproductive behavior; sex-steroid levels were also measured. As predicted, females in below-average body condition had very low estradiol levels and did not show sexual receptivity, whereas males of all body condition indices had significant testosterone levels and displayed active courtship. Testosterone levels and courtship intensity increased gradually (i.e., no step function) with body condition in males, but high estradiol levels and sexual receptivity were seen only in females with body reserves above a critical threshold. Copyright 2002 Elsevier Science (USA)

  9. Reappraisal of Vipera aspis venom neurotoxicity.

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    Elisabeth Ferquel

    Full Text Available BACKGROUND: The variation of venom composition with geography is an important aspect of intraspecific variability in the Vipera genus, although causes of this variability remain unclear. The diversity of snake venom is important both for our understanding of venomous snake evolution and for the preparation of relevant antivenoms to treat envenomations. A geographic intraspecific variation in snake venom composition was recently reported for Vipera aspis aspis venom in France. Since 1992, cases of human envenomation after Vipera aspis aspis bites in south-east France involving unexpected neurological signs were regularly reported. The presence of genes encoding PLA(2 neurotoxins in the Vaa snake genome led us to investigate any neurological symptom associated with snake bites in other regions of France and in neighboring countries. In parallel, we used several approaches to characterize the venom PLA(2 composition of the snakes captured in the same areas. METHODOLOGY/PRINCIPAL FINDINGS: We conducted an epidemiological survey of snake bites in various regions of France. In parallel, we carried out the analysis of the genes and the transcripts encoding venom PLA(2s. We used SELDI technology to study the diversity of PLA(2 in various venom samples. Neurological signs (mainly cranial nerve disturbances were reported after snake bites in three regions of France: Languedoc-Roussillon, Midi-Pyrénées and Provence-Alpes-Côte d'Azur. Genomes of Vipera aspis snakes from south-east France were shown to contain ammodytoxin isoforms never described in the genome of Vipera aspis from other French regions. Surprisingly, transcripts encoding venom neurotoxic PLA(2s were found in snakes of Massif Central region. Accordingly, SELDI analysis of PLA(2 venom composition confirmed the existence of population of neurotoxic Vipera aspis snakes in the west part of the Massif Central mountains. CONCLUSIONS/SIGNIFICANCE: The association of epidemiological studies to

  10. Cross neutralization of dangerous snake venoms from Africa and the Middle East using the VACSERA polyvalent antivenom. Egyptian Organization for Biological Products & Vaccines.

    Science.gov (United States)

    Seddik, Salwa S; Wanas, Soheir; Helmy, Madiha H; Hashem, Mohamed

    2002-12-01

    This study was performed to assess the ability of polyvalent snake venom anti-serum, produced by the Egyptian Organization for Biological Products & Vaccines (VACSERA), to neutralize several toxic activities of snake venoms, not only of those included in the antivenom mixture, but also some additional venoms of snakes from Egyptian, African, and Middle Eastern habitats. In general, the results revealed that polyvalent snake venom anti-serum from VACSERA is highly effective in neutralizing Egyptian snake venoms, especially Naja haje, Naja nigricolles, Naja pallida, Cerastes cerastes, Cerastes cerastes cerastes, Cerastes vipera, Pseudocerastes persicus fieldi, and Walterinnisia egyptia. The antivenom was also effective against Naja haje, Walterinnisia egyptia, and Bites aritans from Saudi Arabia. High activity was obtained against venoms from Naja haje, Naja nigricolles, and Naja pallida of Sudan, as well as the African Naja melanoleuca, Naja mossambica, Naja naja oxiana, Bites gabonica, and Vipera lebetina. Only moderate effectiveness was obtained with Echis coloratus and Echis carinatus, and the polyvalent antiserum was ineffective against the venom of Naja nivea.

  11. A Single Dose of ViperfavTM May Be Inadequate for Vipera ammodytes Snake Bite: A Case Report and Pharmacokinetic Evaluation

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    Tihana Kurtović

    2016-08-01

    Full Text Available ViperfavTM is a commercial F(ab’2 antivenom prepared against European vipers venom. It is safe and effective for treating envenomation caused by Vipera aspis and Vipera berus. Therapeutic efficacy for treating Vipera ammodytes ammodytes (V. a. ammodytes envenoming has not been yet described, although protective efficacy has been demonstrated in preclinical studies. We report on a 32-year-old man bitten by V. a. ammodytes who was treated with Viperfav™. Viperfav™ promptly reduced local extension and improved systemic pathological signs, but 24 h after the incident a recurrence of thrombocytopenia occurred despite a favorable pharmacokinetic profile with systemic clearance (1.64 (mL·h−1·kg−1 and elimination half-life (97 h among the highest ever reported. The recommended dose of Viperfav™ for V. aspis and V. berus bites may be inadequate for serious V. a. ammodytes envenomations. Following V. a. ammodytes bite, serial blood counts and coagulation profiles should be performed to help guide Viperfav™ treatment, along with supplemental administration as indicated.

  12. Immunological Cross-Reactivity and Neutralisation of European Viper Venoms with the Monospecific Vipera berus Antivenom ViperaTAb

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    Nicholas R. Casewell

    2014-08-01

    Full Text Available Medically important cases of snakebite in Europe are predominately caused by European vipers of the genus Vipera. The mainstay of snakebite therapy is polyclonal antibody therapy, referred to as antivenom. Here we investigate the capability of the monospecific V. berus antivenom, ViperaTAb®, to cross-react with, and neutralise lethality induced by, a variety of European vipers. Using ELISA and immunoblotting, we find that ViperaTAb® antibodies recognise and bind to the majority of toxic components found in the venoms of the Vipera species tested at comparably high levels to those observed with V. berus. Using in vivo pre-clinical efficacy studies, we demonstrate that ViperaTAb® effectively neutralises lethality induced by V. berus, V. aspis, V. ammodytes and V. latastei venoms and at much higher levels than those outlined by regulatory pharmacopoeial guidelines. Notably, venom neutralisation was found to be superior to (V. berus, V. aspis and V. latastei, or as equally effective as (V. ammodytes, the monospecific V. ammodytes “Zagreb antivenom”, which has long been successfully used for treating European snake envenomings. This study suggests that ViperaTAb® may be a valuable therapeutic product for treating snakebite by a variety of European vipers found throughout the continent.

  13. Immunological Cross-Reactivity and Neutralisation of European Viper Venoms with the Monospecific Vipera berus Antivenom ViperaTAb

    Science.gov (United States)

    Casewell, Nicholas R.; Al-Abdulla, Ibrahim; Smith, David; Coxon, Ruth; Landon, John

    2014-01-01

    Medically important cases of snakebite in Europe are predominately caused by European vipers of the genus Vipera. The mainstay of snakebite therapy is polyclonal antibody therapy, referred to as antivenom. Here we investigate the capability of the monospecific V. berus antivenom, ViperaTAb®, to cross-react with, and neutralise lethality induced by, a variety of European vipers. Using ELISA and immunoblotting, we find that ViperaTAb® antibodies recognise and bind to the majority of toxic components found in the venoms of the Vipera species tested at comparably high levels to those observed with V. berus. Using in vivo pre-clinical efficacy studies, we demonstrate that ViperaTAb® effectively neutralises lethality induced by V. berus, V. aspis, V. ammodytes and V. latastei venoms and at much higher levels than those outlined by regulatory pharmacopoeial guidelines. Notably, venom neutralisation was found to be superior to (V. berus, V. aspis and V. latastei), or as equally effective as (V. ammodytes), the monospecific V. ammodytes “Zagreb antivenom”, which has long been successfully used for treating European snake envenomings. This study suggests that ViperaTAb® may be a valuable therapeutic product for treating snakebite by a variety of European vipers found throughout the continent. PMID:25153254

  14. [Vipera berus bite--a case report].

    Science.gov (United States)

    Zajkowska, Joanna; Garkowski, Adam; Pancewicz, Sławomir

    2010-11-01

    Cases of bite by common viper (Vipera berus) are rare on the territory of Poland, and the mortality after bites is less than 1%. This paper describes a case of 81-year-old patient with massive swelling, redness and soreness of the right hand, which occurred shortly after the adder bite. In this paper we present composition and mechanisms of the venom's action, clinical symptoms and treatment of poisoning after a snake bite. Based on the reported case authors draw attention to hospital treatment and indications for administration of antivenom as the only causative method of treatment.

  15. Comparative morphology of the skin of Natrix tessellata (family: Colubridae) and Cerastes vipera (family: Viperidae).

    Science.gov (United States)

    Abo-Eleneen, Rasha E; Allam, Ahmed A

    2011-10-01

    We studied beneficial difference of the skin of two snakes. Two snakes were chosen from two different habitats and two families: Colubridae (Natrix tessellata) and Viperidae (Cerastes vipera). The investigations were performed by light and electron microscopy. Histologically, the skin of the studied species show pronounced modifications that correlated with functional demands. The scales in Natrix tessellata overlapped slightly, while in Cerastes vipera they were highly overlapped. SEM shows that scales of Natrix tessellata had bidentate tips while the scales of Cerastes vipera were keeled. Histochemically, in both studied species, melanocytes and collagenous fibres were distributed throughout the dermis. Polysaccharides were highly concentrated in the epidermis and dermis of both species while proteins were highly concentrated only in the epidermis. Transmission electron microscopy (TEM) showed that the skin of both snakes consisted of keratins located in the epidermis. Some lipids and mucus were incorporated into the outer scale surfaces such that lipids were part of the fully keratinised hard layer of the snakes' skins. Lipids are probably responsible for limiting water loss and ion movements across the skin. Melanosomes from epidermal melanocytes were present only in Cerastes vipera. In aggregate, these results indicate that snakeskin may provide an ecological indicator whereby epidermal and integumentary specializations may be ecologically correlated.

  16. Clinical picture of envenoming with the Meadow Viper (Vipera (Acridophaga) ursinii).

    Science.gov (United States)

    Krecsák, László; Zacher, Gábor; Malina, Tamás

    2011-01-01

    The vipers in the Vipera (Acridophaga) ursinii complex are small-sized insectivorous snakes found in parts of central and southern Europe. Subspecies include Vipera ursinii ursinii, Vipera ursinii moldavica, Vipera ursinii macrops, Vipera ursinii rakosiensis, and Vipera ursinii graeca and are commonly known as the meadow vipers. These are the least known European Vipera from a clinical point of view. We identified cases of V. ursinii envenomations through three methods, including literature search in PubMed, ISI web of Knowldge, JSTOR, Biological Abstracts, Zoological Record, using the various combination of the following terms: snakebite, envenoming, bite, venom, ursinii, meadow viper, steppe viper (in English, French, Italian, Hungarian, Croatian, Serbian, Romanian), review of paper-based medical case records of hospitals in Hungary (four) and Romania (one) covering the 1970-July 2010 period, and personal communications of professional and amateur herpetologists studying V. ursinii and snake-handlers bitten by these snakes. We identified 64 cases from subspecies: V. u. ursinii (14), V. u. moldavica (8), V. u. macrops (5), and V. u. rakosiensis (37). Forty-five bites were collected from the literature, 5 from hospitals, 10 cases were communicated by seven herpetologists and four cases by two snake keepers. Bites were mostly asymptomatic. Forty-five envenomings (70%) resulted in mild and moderate local symptoms, involving pain with low-intensity, pruritus, numbness, swelling with or without erythema and/or local hematoma. Bullae (n = 3, 5%), mild superficial necrosis (n = 4, 6%), cellulitis (n = 1, 2%), and moderately extended edema (n = 8, 13%) of the bitten extremity rarely develop. Massive limb edema was recorded in eight (13%) cases. The most common systemic symptoms were dizziness caused by transient hypotension and tachycardia. Gastrointestinal disorders (i.e. nausea, vomiting) were rare (n = 2, 3%) compared to other Vipera, and probably triggered only by

  17. Phospholipases a2 from Viperidae snakes: Differences in membranotropic activity between enzymatically active toxin and its inactive isoforms.

    Science.gov (United States)

    Ghazaryan, Narine A; Ghulikyan, Lusine; Kishmiryan, Arsen; Andreeva, Tatyana V; Utkin, Yuri N; Tsetlin, Victor I; Lomonte, Bruno; Ayvazyan, Naira M

    2015-02-01

    We describe the interaction of various phospholipases A2 (PLA2) from snake venoms of the family Viperidae (Macrovipera lebetina obtusa, Vipera ursinii renardi, Bothrops asper) with giant unilamellar vesicles (GUVs) composed of natural brain phospholipids mixture, visualized through fluorescence microscopy. The membrane fluorescent probes 8-anilino-1-naphthalenesulfonicacid (ANS), LAUDRAN and PRODAN were used to assess the state of the membrane and specifically mark the lipid packing and membrane fluidity. Our results have shown that the three PLA2s which contain either of aspartic acid, serine, or lysine residues at position 49 in the catalytic center, have different effects on the vesicles. The PLA2 with aspartic acid at this position causes the oval deformation of the vesicles, while serine and lysine-containing enzymes lead to an appreciable increase of fluorescence intensity in the vesicles membrane, wherein the shape and dimensions of GUVs have not changed, but in this case GUV aggregation occurs. LAURDAN and PRODAN detect the extent of water penetration into the bilayer surface. We calculated generalized polarization function (GP), showing that for all cases (D49 PLA2, S49 PLA2 and K49 PLA2) both LAUDRAN and PRODAN GP values decrease. A higher LAURDAN GP is indicative of low water penetration in the lipid bilayer in case of K49 PLA2 compared with D49 PLA2, whereas the PRODAN mainly gives information when lipid is in liquid crystalline phase. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Snakes! Snakes! Snakes!

    Science.gov (United States)

    Nature Naturally, 1983

    1983-01-01

    Designed for students in grades 4-6, the teaching unit presents illustrations and facts about snakes. Topics include common snakes found in the United States, how snakes eat, how snakes shed their skin, poisonous snakes, the Eastern Indigo snake, and the anatomy of a snake. A student page includes a crossword puzzle and surprising snake facts. A…

  19. [Molecular cloning and analysis of cDNA sequences encoding serine proteinase and Kunitz type inhibitor in venom gland of Vipera nikolskii viper].

    Science.gov (United States)

    Ramazanova, A S; Fil'kin, S Iu; Starkov, V G; Utkin, Iu N

    2011-01-01

    Serine proteinases and Kunitz type inhibitors are widely represented in venoms of snakes from different genera. During the study of the venoms from snakes inhabiting Russia we have cloned cDNAs encoding new proteins belonging to these protein families. Thus, a new serine proteinase called nikobin was identified in the venom gland of Vipera nikolskii viper. By amino acid sequence deduced from the cDNA sequence, nikobin differs from serine proteinases identified in other snake species. Nikobin amino acid sequence contains 15 unique substitutions. This is the first serine proteinase of viper from Vipera genus for which a complete amino acid sequence established. The cDNA encoding Kunitz type inhibitor was also cloned. The deduced amino acid sequence of inhibitor is homologous to those of other proteins from that snakes of Vipera genus. However there are several unusual amino acid substitutions that might result in the change of biological activity of inhibitor.

  20. [Bites of venomous snakes in Switzerland].

    Science.gov (United States)

    Plate, Andreas; Kupferschmidt, Hugo; Schneemann, Markus

    2016-06-08

    Although snake bites are rare in Europe, there are a constant number of snake bites in Switzerland. There are two domestic venomous snakes in Switzerland: the aspic viper (Vipera aspis) and the common European adder (Vipera berus). Bites from venomous snakes are caused either by one of the two domestic venomous snakes or by an exotic venomous snake kept in a terrarium. Snake- bites can cause both a local and/or a systemic envenoming. Potentially fatal systemic complications are related to disturbances of the hemostatic- and cardiovascular system as well as the central or peripheral nervous system. Beside a symptomatic therapy the administration of antivenom is the only causal therapy to neutralize the venomous toxins.

  1. Evaluation of Iranian Snake ‘Macrovipera lebetina’ Venom Cytotoxicity in Kidney Cell Line HEK-293

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    Hourieh Esmaeili Jahromi

    2016-03-01

    Full Text Available Background:Envenomation by Macrovipera lebetina (M. lebetina is characterized by prominent local tissue damage, hemorrhage, abnormalities in the blood coagulation system, necrosis, and edema. However, the main cause of death after a bite by M. lebetina has been attributed to acute renal failure (ARF. It is unclear whether the venom components have a direct or indirect action in causing ARF. To investigate this point, we looked at the in vitro effect of M. lebetina crude venom, using cultured human embryonic kidney (HEK-293 mono layers as a model. Methods: The effect of M. lebetina snake venom on HEK-293 growth inhibition was determined by the MTT assay and the neutral red uptake assay. The integrity of the cell membrane through LDH release was measured with the Cytotoxicity Detection Kit. Morphological changes in HEK-293 cells were also evaluated using an inverted microscope. Results: In the MTT assay, crude venom showed a significant cytotoxic effect on HEK-293 cells at 24 hours of exposure and was confirmed by the neutral red assay. Also, at 24 hours exposure, crude venom caused a non-significant increase in LDH activity of the culture medium at concentrations above 20 μg/ml. Various morphological abnormalities were observed in cells exposed to the venom and showed loss of their common polygonal shape, appearing as several roughly rounded cells of variable size. The M. lebetina crude venom induced detachment of cells from the plate. Conclusion: Based on the results obtained in this study, it can be concluded that the Iranian snake M. lebetina venom causes a cytotoxic effect on kidney tissue not by necrotic mechanism but rather by secondary effects, including hypotension, hemolysis, hemoglobinuria, rhabdomyolysis, myoglobinuria and disseminated intravascular coagulation (DIC, which may lead to ARF.

  2. Morphometric differences between extant and extinct Italian populations of the adder, Vipera berus (Linnaeus, 1758

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    Augusto Gentilli

    2006-01-01

    Full Text Available Vipera berus (Linnaeus, 1758 is the terrestrial snake showing the widest distribution in the world, occuring from Great Britain, France and Northern Italy to the Sakhalin Island and North Korea (Nilson, 1980; Saint Girons, 1980; Nilson et al., 1994; Nilson & Andrén, 1997a. However, adders do not occur uniformly over their distribution area, but are scattered in several isolated populations (Nilson & Andrén, 1997a. Frequently, ecological traits of borderline and isolated populations differ from those living in the core area of the distribution range of the species, and might be subjected to higher risks of stochastic extinction and higher differentiation rates (Mayr, 1970. For example, meadow vipers (Vipera ursinii show a highly fragmented distribution, many of isolated groups being different subspecies (Nilson & Andrén, 1997b, 2001.

  3. Immunological cross-reactivity and neutralisation of European viper venoms with the monospecific Vipera berus antivenom ViperaTAb

    National Research Council Canada - National Science Library

    Casewell, Nicholas R; Al-Abdulla, Ibrahim; Smith, David; Coxon, Ruth; Landon, John

    2014-01-01

    .... Using ELISA and immunoblotting, we find that ViperaTAb® antibodies recognise and bind to the majority of toxic components found in the venoms of the Vipera species tested at comparably high levels to those observed with V. berus...

  4. A review of neogene and quaternary snakes of Central and Eastern Europe. Part 11: natricinae, elapidae, viperidae

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    Szyndlar, Z.

    1991-08-01

    Full Text Available Remains of Neogene and Quaternary "natricine" colubrids, elapids and viperids, including snakes previously described and those undescribed yet, coming from Poland, Ukraine, Moldavia, Czechoslovakia, Austria, Hungary, Romania, Bulgaria, and Greece are discussed. The following taxa, including 11 extinct species, were recognized: "Natricinae": Neonatrix nova, Neonatrix sp., Palaeonatrix silesiaca, Palaeonatrix lehmani, Natrix longivertebrata, Natrix cf. N. longivertebrata, Natrix natrix, Natrix tesselata, Natrix cf. N. tesselata, Natrix sp., "Natricinae" indet.; Elapidae: Naja romani, Naja sp., cf. Naja sp.; Viperidae: Vipera platyspondyla, Vipera sarmatica, Vipera burgenlandica, Vipera gedulyi, Vipera kuchurganica, Vipera antiqua, Vipera cf. V. ammodytes, Vipera berus, Vipera sp ('Oriental vipers' group, Vipera sp. ('aspis' group, Vipera sp. ('berus' group, Vipera sp. . (status unknown. Taxonomic status of two other extinct species, Natrix parva and Laophis crotaloides, is uncertain. Modern species appeared fírst in Central and East Europe in the middle Pliocene (MN 15. Older snakes belonged to extinct species of either extinct or extant genera; taxonomic distinction of most extinct genera is, however, not fully demonstrated. Best recognized oldest snakes from the area (Elapidae, Viperidae, and sorne Colubridae are clearly referable to modern genera and intrageneric subdivisions occurring today are observed in oldest (Iower Miocene remains; closest living relatives of these fossils are presently distributed in the Oriental Realm.Se revisan y estudian los restos neógenos y cuaternarios de colúbridos «natricinos», elápidos y vipéridos, incluyendo tanto serpientes previamente descritas como- otras inéditas. Los materiales analizados proceden de Polonia, Ukrania, Moldavia, Checoslovaquia, Austria, Hungría, Rumania, Bulgaria y Grecia. Se reconocen los siguientes taxones, incluyendo 11 especies extinguidas: Natricinae: Neonatrix nova

  5. Data on the reproduction of a Caucasian Viper, Vipera kaznakovi Nikolsky, 1909 (Serpentes: Viperidae from Hopa (Northeastern Anatolia, Turkey

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    Bayram Göçmen

    2013-12-01

    Full Text Available In the current study we report an observation of a Caucasian Viper, Vipera kaznakovi from Hopa (Artvin, Turkey giving birth. During our field studies, we captured a female Vipera kaznakovi on July 21, 2012 from Esenkıyı village, Hopa (Artvin, Turkey, it was brought to the laboratory and kept in a terrarium for a period until May 28, 2013. The female (SVL= 483 mm, total length, TL = 541 mm gave birth to eight young (mean SVL= 146 mm, mean TL= 161.4 mm, range= 155 – 172 mm; mean weight, W= 3.11 g, range= 2.6 – 3.4 g on August 11, 2012. In six and a half months, the juvenile snakes had reached 163 mm SVL, 187 mm TL and 5.1g W and increased their size by approximately 15%.

  6. Clinical and biochemical changes in 53 Swedish dogs bitten by the European adder - Vipera berus

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    Frendin Jan HM

    2010-04-01

    Full Text Available Abstract Background Every year many dogs in Sweden are bitten by Vipera berus, the only venomous viper in Sweden. This prospective study investigated clinical signs, some biochemical parameters, treatment, and progress of disease after snakebite in 53 dogs. Effects of treatment with and without glucocorticoids were evaluated. Methods All fifty-three dogs bitten by Vipera berus were examined the same day the dog was bitten and the next day. Two more examinations during 23 days post snake bite were included. Creatinine, creatine kinase (CK, alanine aminotransferase (ALT, glutamate dehydrogenase (GLDH, alkaline phosphatase (ALP and bile acid results were followed through 3 to 4 samplings from 34 of the dogs. Results All dogs had variable severity of local swelling in the bite area and 73 per cent had affected mental status. Initial cardiac auscultation examination was normal in all dogs, but six dogs had cardiac abnormalities at their second examination, including cardiac arrhythmias and cardiac murmurs. All dogs received fluid therapy, 36 dogs were given analgesics, 22 dogs were treated with glucocorticoids, and ten dogs were treated with antibiotics. Evidence of transient muscle damage (increased CK was seen one day after the snake bite in 15 (54% of 28 sampled dogs. Moderate changes in hepatic test results occurred in 1 dog and several dogs (22 of 34 had transient, minor increases in one or more hepatic test result. No dog died during the observation period as a consequence of the snake bite. Conclusions Snake bite caused local swelling in all dogs and mental depression of short duration in most dogs. Some dogs had transient clinical signs that could be indicative of cardiac injury and some other had transient biochemical signs of liver injury. Treatment with glucocorticoids did not have any clear positive or negative effect on clinical signs and mortality.

  7. Clinical and biochemical changes in 53 Swedish dogs bitten by the European adder--Vipera berus.

    Science.gov (United States)

    Lervik, Jessica Berger; Lilliehöök, Inger; Frendin, Jan H M

    2010-04-23

    Every year many dogs in Sweden are bitten by Vipera berus, the only venomous viper in Sweden. This prospective study investigated clinical signs, some biochemical parameters, treatment, and progress of disease after snakebite in 53 dogs. Effects of treatment with and without glucocorticoids were evaluated. All fifty-three dogs bitten by Vipera berus were examined the same day the dog was bitten and the next day. Two more examinations during 23 days post snake bite were included. Creatinine, creatine kinase (CK), alanine aminotransferase (ALT), glutamate dehydrogenase (GLDH), alkaline phosphatase (ALP) and bile acid results were followed through 3 to 4 samplings from 34 of the dogs. All dogs had variable severity of local swelling in the bite area and 73 per cent had affected mental status. Initial cardiac auscultation examination was normal in all dogs, but six dogs had cardiac abnormalities at their second examination, including cardiac arrhythmias and cardiac murmurs. All dogs received fluid therapy, 36 dogs were given analgesics, 22 dogs were treated with glucocorticoids, and ten dogs were treated with antibiotics. Evidence of transient muscle damage (increased CK) was seen one day after the snake bite in 15 (54%) of 28 sampled dogs. Moderate changes in hepatic test results occurred in 1 dog and several dogs (22 of 34) had transient, minor increases in one or more hepatic test result. No dog died during the observation period as a consequence of the snake bite. Snake bite caused local swelling in all dogs and mental depression of short duration in most dogs. Some dogs had transient clinical signs that could be indicative of cardiac injury and some other had transient biochemical signs of liver injury. Treatment with glucocorticoids did not have any clear positive or negative effect on clinical signs and mortality.

  8. Proteome and Peptidome of Vipera berus berus Venom

    Directory of Open Access Journals (Sweden)

    Aleksandra Bocian

    2016-10-01

    Full Text Available Snake venom is a rich source of peptides and proteins with a wide range of actions. Many of the venom components are currently being tested for their usefulness in the treatment of many diseases ranging from neurological and cardiovascular to cancer. It is also important to constantly search for new proteins and peptides with properties not yet described. The venom of Vipera berus berus has hemolytic, proteolytic and cytotoxic properties, but its exact composition and the factors responsible for these properties are not known. Therefore, an attempt was made to identify proteins and peptides derived from this species venom by using high resolution two-dimensional electrophoresis and MALDI ToF/ToF mass spectrometry. A total of 11 protein classes have been identified mainly proteases but also l-amino acid oxidases, C-type lectin like proteins, cysteine-rich venom proteins and phospholipases A2 and 4 peptides of molecular weight less than 1500 Da. Most of the identified proteins are responsible for the highly hemotoxic properties of the venom. Presence of venom phospholipases A2 and l-amino acid oxidases cause moderate neuro-, myo- and cytotoxicity. All successfully identified peptides belong to the bradykinin-potentiating peptides family. The mass spectrometry data are available via ProteomeXchange with identifier PXD004958.

  9. Reproductive cycle of free-living male Saharan sand vipers, Cerastes vipera (Viperidae) in the Negev desert, Israel.

    Science.gov (United States)

    Sivan, Jaim; Kam, Michael; Hadad, Shlomo; Allan Degen, A; Rozenboim, Israel; Rosenstrauch, Avi

    2012-11-01

    The Saharan sand viper, Cerastes vipera (Linnaeus, 1758), is distributed in all Saharan countries, being confined to sand and dune systems. This relatively small snake, up to 35 cm, is nocturnal, is active from spring to autumn (April to October) and hibernates during the winter (November to March). We predicted that C. vipera would have peak plasma testosterone concentration at mating and that the vas deferens would contain abundant spermatozoa at that time. To test our predictions, we collected information on the time of mating and measured monthly testosterone concentration, testes size and testicular activity in free-living male C. vipera during its active period from April to October. Mating occurred only during spring. The pattern of plasma testosterone concentration, testes volume, seminiferous tubule diameter and spermatogenesis all followed the general pattern of high values in autumn and spring and low values in early summer. Our predictions were partially supported. There was a high plasma testosterone concentration at mating in spring and the vas deferens contained abundant spermatozoa, as predicted, but there was also a high plasma testosterone concentration in autumn without mating. We concluded that: (1) males are both aestival in that they produce spermatozoa in autumn, which they store over the winter hibernation period, and vernal in that they produce spermatozoa in spring prior to mating; (2) matings are associated with spermatogenesis; and (3) the high plasma testosterone concentration is concomitant with both matings and spermatogenesis in spring and with spermatogenesis in autumn. We propose that C. vipera has a single peak of testicular activity and plasma testosterone concentration which start in autumn and end in spring. We also propose that spermatogenesis is prior to spring mating and, consequently, is prenuptial. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Preliminary evaluation of total protein concentration and electrophoretic protein fractions in fresh and frozen serum from wild Horned Vipers (Vipera ammodytes ammodytes).

    Science.gov (United States)

    Proverbio, Daniela; de Giorgi, Giada Bagnagatti; Della Pepa, Alessandra; Baggiani, Luciana; Spada, Eva; Perego, Roberta; Comazzi, Carlo; Belloli, Angelo

    2012-12-01

    Determination of the health status of reptiles is based on physical examination and evaluation of hematologic and biochemical values. Evaluation of serum total protein (TP) concentration and protein fractions plays an important role in health assessment; however, little is known about references value for these analytes in wild viperoid snakes. In addition, studies evaluating the stability of proteins in frozen viperoid serum are lacking. The aims of this study were to establish preliminary reference values for concentrations of TP and protein fractions in serum from wild vipers and to evaluate the stability of serum proteins in frozen serum samples from viperoid snakes. Blood samples were collected from wild Horned Vipers (Vipera ammodytes ammodytes). Using fresh serum, TP concentrations were determined using the biuret method and protein fractions were analyzed using agarose gel electrophoresis (AGE); albumin/globulin ratios were calculated. Analyses were also performed on serum frozen at -20°C for 70 days and then thawed. Pre- and post-storage results were compared using the Mann-Whitney U-test. Five adult wild Horned Vipers were sampled and comprised 4 males and 1 female. The female snake had higher TP concentrations than the male snakes. The electrophoretic patterns demonstrated 6 protein fractions that were similar for all 5 snakes. There were no significant changes in the concentrations of the 6 protein fractions post-storage; the percentage of the alpha-1 fraction was increased in frozen/thawed serum. Total protein concentrations in serum from Vipera ammodytes ammodytes were in agreement with published reference intervals for healthy reptiles and viperoid snakes. Serum protein fractions were easy to identify using AGE electrophoresis. © 2012 American Society for Veterinary Clinical Pathology.

  11. Nuclear markers support the mitochondrial phylogeny of Vipera ursinii-renardi complex (Squamata: Viperidae) and species status for the Greek meadow viper.

    Science.gov (United States)

    Mizsei, Edvárd; Jablonski, Daniel; Roussos, Stephanos A; Dimaki, Maria; Ioannidis, Yannis; Nilson, Göran; Nagy, Zoltán T

    2017-01-31

    Meadow vipers (Vipera ursinii-renardi complex) are small-bodied snakes that live in either lowland grasslands or montane subalpine-alpine meadows spanning a distribution from France to western China. This complex has previously been the focus of several taxonomic studies which were based mainly on morphological, allozyme or immunological characters and did not clearly resolve the relationships between the various taxa. Recent mitochondrial DNA analyses found unexpected relationships within the complex which had taxonomical consequences for the detected lineages. The most surprising was the basal phylogenetic position of Vipera ursinii graeca, a taxon described almost 30 years ago from the mountains of Greece. We present here new analyses of three nuclear markers (BDNF, NT3, PRLR; a first for studies of meadow and steppe vipers) as well as analyses of newly obtained mitochondrial DNA sequences (CYT B, ND4).Our Bayesian analyses of nuclear sequences are concordant with previous studies of mitochondrial DNA, in that the phylogenetic position of the graeca clade is a clearly distinguished and distinct lineage separated from all other taxa in the complex. These phylogenetic results are also supported by a distinct morphology, ecology and isolated distribution of this unique taxon. Based on several data sets and an integrative species concept we recommend to elevate this taxon to species level: Vipera graeca Nilson & Andrén, 1988 stat. nov.

  12. [The viper--Finland's only poisonous snake].

    Science.gov (United States)

    Vuori, Arno

    2011-01-01

    The viper (Vipera berus) is the most common poisonous snake in Europe, and the only one in Finland. In viper bites, highly varying amounts of venom end up into the victim, whereby prediction of the progression of symptoms of poisoning is very difficult. A severe clinical picture must always be anticipated. The size of the victim has also an effect on the outcome. Adequate monitoring and when necessary, massive fluid therapy are essential in the treatment. Due to possible kidney damage, anti-inflammatory drugs are not recommended. Severe or rapidly progressing symptoms require the use of an antidote.

  13. Assessment of leukocygram of Vipera berus from Samara region

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    Romanova Elena Borisovna

    2016-12-01

    Full Text Available The leucogram of peripheral blood of the common adder Vipera berus inhabiting the national park "Samarskaya Luka" and the forested urban area of Samara were studied. In the adders from Samara the activation of immune processes, and the enhancement of the blood protective function were revealed. It was shown that the determined features of leucogram were connected with genetic characteristics of adders’ population.

  14. The adder (Vipera berus in Southern Altay Mountains: population characteristics, distribution, morphology and phylogenetic position

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    Shaopeng Cui

    2016-08-01

    Full Text Available As the most widely distributed snake in Eurasia, the adder (Vipera berus has been extensively investigated in Europe but poorly understood in Asia. The Southern Altay Mountains represent the adder’s southern distribution limit in Central Asia, whereas its population status has never been assessed. We conducted, for the first time, field surveys for the adder at two areas of Southern Altay Mountains using a combination of line transects and random searches. We also described the morphological characteristics of the collected specimens and conducted analyses of external morphology and molecular phylogeny. The results showed that the adder distributed in both survey sites and we recorded a total of 34 sightings. In Kanas river valley, the estimated encounter rate over a total of 137 km transects was 0.15 ± 0.05 sightings/km. The occurrence of melanism was only 17%. The small size was typical for the adders in Southern Altay Mountains in contrast to other geographic populations of the nominate subspecies. A phylogenetic tree obtained by Bayesian Inference based on DNA sequences of the mitochondrial cytochrome b (1,023 bp grouped them within the Northern clade of the species but failed to separate them from the subspecies V. b. sachalinensis. Our discovery extends the distribution range of V. berus and provides a basis for further researches. We discuss the hypothesis that the adder expands its distribution border to the southwest along the mountains’ elevation gradient, but the population abundance declines gradually due to a drying climate.

  15. Incidence of snake bites in kashan, iran during an eight year period (2004-2011).

    Science.gov (United States)

    Dehghani, Rouhullah; Rabani, Davarkhah; Panjeh Shahi, Morteza; Jazayeri, Mehrdad; Sabahi Bidgoli, Mohammd

    2012-01-01

    Snake bites are one of the significant health problems in the tropical and subtropical regions. Snake bite is a common medical emergency in Iran, and the epidemiological features and management of such cases vary from region to region. This present research study was conducted to obtain new information about the epidemiology of snake bites in the region of Kashan, located in the central part of Iran. This research was a descriptive retrospective study. Data from 2004 to 2011 of snakebite cases were collected from case reports. Information included; age and sex of the victim, district, month of incident, mortality, and time of bite. The results of this study showed that the majority of snake bite patients were male (96%). The age distribution of patients indicated that the greatest rate of snake bites occurred among the 15-24 year old group. Data collected in this study revealed that the highest incidence of snake bite cases took place in summer (60%) and the lowest number occurred in winter, with no snake bite cases being recorded. The peak number of snakebite cases was seen during June-September. It was concluded that snake bite cases in Kashan are similar to other areas in Iran from an epidemiological point of view, including; age distribution rates, gender and site of the bites. The existence of Macrov ipera lebetina, a dangerous venomous snake, can cause a range of clinical effects among residents in central parts of Iran, such as Kashan area.

  16. Snake bites

    Science.gov (United States)

    ... bites by any of the following: Cobra Copperhead Coral snake Cottonmouth (water moccasin) Rattlesnake Various snakes found at ... Swelling Thirst Tiredness Tissue damage Weakness Weak pulse Coral snake bites may be painless at first. Major symptoms ...

  17. Morphological changes of proteolipid giant unilamellar vesicles affected by Macrovipera lebetina obtusa venom visualized with fluorescence microscope.

    Science.gov (United States)

    Ghazaryan, N A; Ghulikyan, L A; Ayvazyan, N M

    2013-08-01

    As a rule, zootoxins are complex and biologically active, and therefore the greater part of zootoxins is subjected to biotransformation and interacts with biological membranes. In this case, the interaction of different venom components with the membranes is not always the same. The present study shows how the giant unilamellar vesicles (GUV) from bovine brain proteolipids interact with Macrovipera lebetina obtusa venom. GUV (mean diameter 30 μm) were formed by the electroformation method. We used 8-anilino-1-naphthalenesulfonic acid and pyrene as fluorescence probes, which allowed us to quantify the fluidity changes in the membrane by measuring the fluorescence intensity.

  18. Snake bite: coral snakes.

    Science.gov (United States)

    Peterson, Michael E

    2006-11-01

    North American coral snakes are distinctively colored beginning with a black snout and an alternating pattern of black, yellow, and red. They have fixed front fangs and a poorly developed system for venom delivery, requiring a chewing action to inject the venom. The severity of a coral snake bite is related to the volume of venom injected and the size of the victim. The length of the snake correlates positively with the snakes venom yield. Coral snake venom is primarily neurotoxic with little local tissue reaction or pain at the bite site. The net effect of the neurotoxins is a curare like syndrome. In canine victims there have been reports of marked hemolysis with severe anemia and hemoglobinuria. The onset of clinical signs may be delayed for as much as 10 to 18 hours. The victim begins to have alterations in mental status and develops generalized weakness and muscle fasciculations. Progression to paralysis of the limbs and respiratory muscles then follows. The best flied response to coral snake envenomation is rapid transport to a veterinary medical facility capable of 24 hour critical care and assisted ventilation. First aid treatment advocated in Australia for Elapid bites is the immediate use of a compression bandage. The victim should be hospitalized for a minimum of 48 hours for continuous monitoring. The only definitive treatment for coral snake envenomation is the administration of antivenin (M. fulvius). Once clinical signs of coral snake envenomation become manifest they progress with alarming rapidity and are difficult to reverse. If antivenin is not available or if its administration is delayed, supportive care includes respiratory support. Assisted mechanical ventilation can be used but may have to be employed for up to 48 to 72 hours.

  19. Antitumoral Potential of Tunisian Snake Venoms Secreted Phospholipases A2

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    Raoudha Zouari-Kessentini

    2013-01-01

    Full Text Available Phospholipases type A2 (PLA2s are the most abundant proteins found in Viperidae snake venom. They are quite fascinating from both a biological and structural point of view. Despite similarity in their structures and common catalytic properties, they exhibit a wide spectrum of pharmacological activities. Besides being hydrolases, secreted phospholipases A2 (sPLA2 are an important group of toxins, whose action at the molecular level is still a matter of debate. These proteins can display toxic effects by different mechanisms. In addition to neurotoxicity, myotoxicity, hemolytic activity, antibacterial, anticoagulant, and antiplatelet effects, some venom PLA2s show antitumor and antiangiogenic activities by mechanisms independent of their enzymatic activity. This paper aims to discuss original finding against anti-tumor and anti-angiogenic activities of sPLA2 isolated from Tunisian vipers: Cerastes cerastes and Macrovipera lebetina, representing new tools to target specific integrins, mainly, and integrins.

  20. Antitumoral Potential of Tunisian Snake Venoms Secreted Phospholipases A2

    Science.gov (United States)

    Zouari-Kessentini, Raoudha; Srairi-Abid, Najet; Bazaa, Amine; El Ayeb, Mohamed; Luis, Jose; Marrakchi, Naziha

    2013-01-01

    Phospholipases type A2 (PLA2s) are the most abundant proteins found in Viperidae snake venom. They are quite fascinating from both a biological and structural point of view. Despite similarity in their structures and common catalytic properties, they exhibit a wide spectrum of pharmacological activities. Besides being hydrolases, secreted phospholipases A2 (sPLA2) are an important group of toxins, whose action at the molecular level is still a matter of debate. These proteins can display toxic effects by different mechanisms. In addition to neurotoxicity, myotoxicity, hemolytic activity, antibacterial, anticoagulant, and antiplatelet effects, some venom PLA2s show antitumor and antiangiogenic activities by mechanisms independent of their enzymatic activity. This paper aims to discuss original finding against anti-tumor and anti-angiogenic activities of sPLA2 isolated from Tunisian vipers: Cerastes cerastes and Macrovipera lebetina, representing new tools to target specific integrins, mainly, α5β1 and αv integrins. PMID:23509718

  1. [Envenoming by common viper (Vipera berus)--subject still exists...].

    Science.gov (United States)

    Ciszowski, Krzysztof; Modła, Arkadiusz

    2004-01-01

    The only venomous reptile that naturally occurs in Poland is the adder or common viper (Vipera berus). Its bites are not of great epidemiological importance, but in some cases serious life-threatening symptoms may appear. The most common symptoms of adder envenomation are: local edema, reddening and pain of the bitten site and also the general symptoms coming from the alimentary tract (vomiting, diarrhoea, abdominal pain), the circulatory system (hypotension, shock, ECG abnormalities), the central nervous system (sleepiness, vertigo, disorientation, loss of consciousness), hematological symptoms (leukocytosis, hemolysis, coagulopathy) and allergic symptoms (fever, urticaria, angio-oedema). In the present study we described the case of a twenty-year-old patient hospitalized at the Toxicology Department of the Collegium Medicum UJ after a viper bite. Except for some above-mentioned symptoms he also developed ocular symptoms like ptosis and blurred vision. Such symptoms after the common viper bite have not been described in the literature till now. The cause of them seems to be an intense allergic reaction in the region of the orbit and eyelids all the more so because the patient had the positive allergy history. However, taking into account the latest reports from the literature, a neurotoxic action of some components of the Vipera berus venom may also play a role. Because of the developing general symptoms a specific equine antivenom was administered to the patient, apart from the supportive care, without any serious side effects that usually are observed after the use of such a kind of sera. It is thought that the sheep antivenom is better than the equine one considering a lack of allergic side effects. As a result of applied treatment the local and general symptoms including ocular symptoms subsided.

  2. Seasonal biotic and abiotic factors affecting hunting strategy in free-living Saharan sand vipers, Cerastes vipera.

    Science.gov (United States)

    Horesh, Sefi J A; Sivan, Jaim; Rosenstrauch, Avi; Tesler, Itay; Degen, A Allan; Kam, Michael

    2017-02-01

    Sit-and-wait ambushing and active hunting are two strategies used by predators to capture prey. In snakes, hunting strategy is conserved phylogenetically; most species employ only one strategy. Active hunters encounter and capture more prey but invest more energy in hunting and have higher risks of being predated. This trade-off is important to small predators. The small Cerastes vipera employs both modes of hunting, which is unlike most viperids which use only sit-and wait ambushing. This species hibernates in October and emerges in April. Energy intake should be high prior to hibernation to overcome the non-feeding hibernation period and for reproduction on their emergence. We predicted that more individuals would hunt actively towards hibernation and an abiotic factor would trigger this response. Furthermore, since more energy is required for active hunting, we predicted that snakes in good body condition would use active hunting to a greater extent than snakes in poor body condition. To test our predictions, we tracked free-living snakes year round and determined their hunting strategy, estimated their body condition index (BCI), and calculated circannual parameters of day length as environmental cues known to affect animal behaviour. Two novel findings emerged in this study, namely, hunting strategy was affected significantly by 1) the circannual change in day length and 2) by BCI. The proportion of active hunters increased from 5% in April to over 30% in October and BCI of active foragers was higher than that of sit-and-wait foragers and, therefore, our predictions were supported. The entrainment between the proportion of active hunting and the abiotic factor is indicative of an adaptive function for choosing a hunting strategy. A trend was evident among life stages. When all life stages were present (September-October), the proportion of active foragers increased with age: 0.0% among neonates, 18.2% among juveniles and 31.4% among adults. We concluded that

  3. Snake bite.

    Science.gov (United States)

    Warrell, David A

    2010-01-02

    Snake bite is a common and frequently devastating environmental and occupational disease, especially in rural areas of tropical developing countries. Its public health importance has been largely ignored by medical science. Snake venoms are rich in protein and peptide toxins that have specificity for a wide range of tissue receptors, making them clinically challenging and scientifically fascinating, especially for drug design. Although the full burden of human suffering attributable to snake bite remains obscure, hundreds of thousands of people are known to be envenomed and tens of thousands are killed or maimed by snakes every year. Preventive efforts should be aimed towards education of affected communities to use proper footwear and to reduce the risk of contact with snakes to a minimum through understanding of snakes' behaviour. To treat envenoming, the production and clinical use of antivenom must be improved. Increased collaboration between clinicians, epidemiologists, and laboratory toxinologists should enhance the understanding and treatment of envenoming. Copyright 2010 Elsevier Ltd. All rights reserved.

  4. Age-dependent variations in the venom proteins of Vipera xanthina (Gray, 1849) (Ophidia: Viperidae).

    Science.gov (United States)

    Arikan, Hüseyin; Alpagut Keskin, Nurşen; Cevik, I Ethem; Ilgaz, Cetin

    2006-01-01

    In this study, polyacrylamide disc gel electrophoresis and densitometry analysis methods were used to analyze venom extracts of Vipera xanthina specimens of different lengths (35, 47 and 88 cm) collected from the same locality. The electropherograms of the venom protein samples showed age-dependent qualitative and quantitative variations.

  5. Cysteine-rich venom proteins from the snakes of Viperinae subfamily - molecular cloning and phylogenetic relationship.

    Science.gov (United States)

    Ramazanova, Anna S; Starkov, Vladislav G; Osipov, Alexey V; Ziganshin, Rustam H; Filkin, Sergey Yu; Tsetlin, Victor I; Utkin, Yuri N

    2009-01-01

    Cysteine-rich proteins found in animal venoms (CRISP-Vs) are members of a large family of cysteine-rich secretory proteins (CRISPs). CRISP-Vs acting on different ion channels were found in venoms or mRNA (cDNA) encoding CRISP-Vs were cloned from snakes of three main families (Elapidae, Colubridae and Viperidae). About thirty snake CRISP-Vs were sequenced so far, however no complete sequence for CRISP-V from Viperinae subfamily was reported. We have cloned and sequenced for the first time cDNAs encoding CRISP-Vs from Vipera nikolskii and Vipera berus vipers (Viperinae). The deduced mature CRISP-V amino acid sequences consist of 220 amino acid residues. Phylogenetic analysis showed that viper proteins are closely related to those of Crotalinae snakes. The presence of CRISP-V in the V. berus venom was revealed using a combination of gel-filtration chromatography, electrophoresis and MALDI mass spectrometry. The finding of the putative channel blocker in viper venom may indicate its action on prey nervous system.

  6. Individual variability of venom from the European adder (Vipera berus berus) from one locality in Eastern Hungary.

    Science.gov (United States)

    Malina, Tamás; Krecsák, László; Westerström, Alexander; Szemán-Nagy, Gábor; Gyémánt, Gyöngyi; M-Hamvas, Márta; Rowan, Edward G; Harvey, Alan L; Warrell, David A; Pál, Balázs; Rusznák, Zoltán; Vasas, Gábor

    2017-09-01

    We have revealed intra-population variability among venom samples from several individual European adders (Vipera berus berus) within a defined population in Eastern Hungary. Individual differences in venom pattern were noticed, both gender-specific and age-related, by one-dimensional electrophoresis. Gelatin zymography demonstrated that these individual venoms have different degradation profiles indicating varying protease activity in the specimens from adders of different ages and genders. Some specimens shared a conserved region of substrate degradation, while others had lower or extremely low protease activity. Phospholipase A 2 activity of venoms was similar but not identical. Interspecimen diversity of the venom phospholipase A 2 -spectra (based on the components' molecular masses) was detected by MALDI-TOF MS. The lethal toxicity of venoms (LD 50 ) also showed differences among individual snakes. Extracted venom samples had varying neuromuscular paralysing effect on chick biventer cervicis nerve-muscle preparations. The paralysing effect of venom was lost when calcium in the physiological salt solution was replaced by strontium; indicating that the block of twitch responses to nerve stimulation is associated with the activity of a phospholipase-dependent neurotoxin. In contrast to the studied V. b. berus venoms from different geographical regions so far, this is the first V. b. berus population discovered to have predominantly neurotoxic neuromuscular activity. The relevance of varying venom yields is also discussed. This study demonstrates that individual venom variation among V. b. berus living in particular area of Eastern Hungary might contribute to a wider range of clinical manifestations of V. b. berus envenoming than elsewhere in Europe. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Dictionary Snakes

    DEFF Research Database (Denmark)

    Dahl, Anders Bjorholm; Dahl, Vedrana Andersen

    2014-01-01

    for image segmentation that operates without training data. Our method is based on a probabilistic dictionary of image patches coupled with a deformable model inspired by snakes and active contours without edges. We separate the image into two classes based on the information provided by the evolving curve...

  8. Vixapatin (VP12, a C-Type Lectin-Protein from Vipera xantina palestinae Venom: Characterization as a Novel Anti-angiogenic Compound

    Directory of Open Access Journals (Sweden)

    Philip Lazarovici

    2012-10-01

    Full Text Available A C-type lectin-like protein (CTL, originally identified as VP12 and lately named Vixapatin, was isolated and characterized from Israeli viper Vipera xantina palestinae snake venom. This CTL was characterized as a selective α2β1 integrin inhibitor with anti-melanoma metastatic activity. The major aim of the present study was to prove the possibility that this protein is also a potent novel anti-angiogenic compound. Using an adhesion assay, we demonstrated that Vixapatin selectively and potently inhibited the α2 mediated adhesion of K562 over-expressing cells, with IC50 of 3 nM. 3 nM Vixapatin blocked proliferation of human dermal microvascular endothelial cells (HDMEC; 25 nM inhibited collagen I induced migration of human fibrosarcoma HT-1080 cells; and 50 nM rat C6 glioma and human breast carcinoma MDA-MB-231 cells. 1 µM Vixapatin reduced HDMEC tube formation by 75% in a Matrigel assay. Furthermore, 1 µM Vixapatin decreased by 70% bFGF-induced physiological angiogenesis, and by 94% C6 glioma-induced pathological angiogenesis, in shell-less embryonic quail chorioallantoic membrane assay. Vixapatin’s ability to inhibit all steps of the angiogenesis process suggest that it is a novel pharmacological tool for studying α2β1 integrin mediated angiogenesis and a lead compound for the development of a novel anti-angiogenic/angiostatic/anti-cancer drug.

  9. Snakes antibodies.

    Science.gov (United States)

    Gambón-Deza, Francisco; Sánchez-Espinel, Christian; Mirete-Bachiller, Serafín; Magadán-Mompó, Susana

    2012-09-01

    Immunoglobulins are basic molecules of the immune system of vertebrates. In previous studies we described the immunoglobulins found in two squamata reptiles, Anolis carolinensis and Eublepharis macularius. Snakes are squamata reptiles too but they have undergone an extreme evolutionary process. We therefore wanted to know how these changes affected their immunoglobulin coding genes. To perform this analysis we studied five snake transcriptomes and two genome draft sequences. Sequences coding for immunoglobulin M (IgM), immunoglobulin D (IgD) and two classes of immunoglobulin Y (IgY - named IgYa and IgYb-) were found in all of them. Moreover, the Thamnophis elegans transcriptome and Python molurus genome draft sequences showed a third class of IgY, the IgYc, whose constant region only presents three domains and lacks the CH2. All data suggest that the IgYb is the evolutionary origin of this IgYc. An exhaustive search of the light chains were carried out, being lambda the only light chain found in snakes. The results provide a clear picture of the immunoglobulins present in the suborder Serpentes. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Parasite assemblages in the Western whip snake Hierophis viridiflavus carbonarius (Colubridae) from southern Italy.

    Science.gov (United States)

    Santoro, M; Aznar, F J; Mattiucci, S; Kinsella, J M; Pellegrino, F; Cipriani, P; Nascetti, G

    2013-09-01

    Parasite assemblages of the Western whip snake Hierophis viridiflavus carbonarius were investigated from the Calabria region in southern Italy. A total of 14 parasite taxa including 6 nematodes, 3 acanthocephalans, 2 cestodes, 2 digeneans and a single pentastomid was identified. Within the study area, H. v. carbonarius serves as the final host for seven species of helminths, of which only four (Hexametra quadricornis, Kalicephalus viperae, Paracapillaria sonsinoi and Renifer aniarum) can be considered as snake specialists, while one (Oswaldocruzia filiformis) is shared with other reptiles and amphibians, and two (Paradistomum mutabile and Rhabdias fuscovenosa) with lizards. A large proportion of larval forms of six helminth taxa (about 95% of all helminths collected) was found, for which H. v. carbonarius serves as an intermediate and/or paratenic host; however, adult stages of helminths were prevalent in snakes with snout-to-vent length greater than 70 cm. Our results suggest that ontogenetic and ecological factors should exert a strong influence upon the helminth assemblage of Western whip snakes. We concluded that H. v. carbonarius plays an important role in southern Italy as an intermediate/paratenic host for species of helminths infecting vertebrate groups which may include this snake species within their feeding chain. Eleven taxa, including three potential agents of zoonosis, were added to the poorly known parasite fauna of this host.

  11. Snake classification from images

    OpenAIRE

    James, Alex.

    2017-01-01

    Incorrect snake identification from the observable visual traits is a major reason of death resulting from snake bites. So far no automatic classification method has been proposed to distinguish snakes by deciphering the taxonomy features of snake for the two major species of snakes i.e. Elapidae and Viperidae. We present a parallel processed inter-feature product similarity fusion based automatic classification of Spectacled Cobra, Russel's Viper, King Cobra, Common Krait, Saw Scaled Viper, ...

  12. Occurrence of European Adder (Vipera berus, Viperidae, Ophidia on Vlasina Plateau (Southeastern Serbia

    Directory of Open Access Journals (Sweden)

    Crnobrnja-Isailović, J.

    2011-09-01

    Full Text Available The European adder (Vipera berus is among the most widespread reptile species in Europe, but it’s distribution at the Balkan Peninsula seems to be scarce and fragmented. As going toward the south, specimens were more frequently found in the vegetational zone of boreal forests and high alpine pastures. In the South-eastern Serbia, recent occurrence of European adder was confirmed on the Vlasina Plateau, in June 2010, in a mosaic-complex of peat bogs and marsh vegetation. Recent engagement of ecology students from University of Niš in mapping actual local distribution of adder will help locating key spots for its conservation in this area.

  13. Frequency and effort of reproduction in female Vipera aspis from a southern population

    Science.gov (United States)

    Zuffi, Marco A. L.; Giudici, Federico; Ioalè, Paolo

    1999-11-01

    The frequency of reproduction of the asp viper ( Vipera aspis, Viperidae) was studied in a population living along the coasts of central Italy. An annual reproductive cycle seemed to be the rule during the 5-year study period. Annual reproduction, high average mass of reproductive females, and large size of neonates, compared with other northern or continental populations, are presumably due to the particularly suitable climatic conditions of the area, as in most coastal habitats of the Mediterranean region. Such a scenario should influence the extent of the feeding period, which allows females, within a few months after parturition, to regain their previous body condition and reproduce again the following year.

  14. Dangerous snakes, deadly snakes and medically important snakes

    OpenAIRE

    Silva, Anjana

    2013-01-01

    This correspondence argues that the dangerousness of a venomous snake species is not solely determined by the venom characteristics or the lethality of the snake, and recognizes that medical importance comprises a key variable as well. The medical importance of a snake is determined by several factors ? including frequency of medical attention after a bite, local or systemic envenomation provoked by the bite, fatal bites, long term consequences, availability of antivenom therapy as well as th...

  15. Systématique et répartition de Vipera ursinii (Bonaparte, 1835) (Reptilia, Viperidae), en Roumanie

    NARCIS (Netherlands)

    Vancea, St.; Saint Girons, H.; Fuhn, I.E.; Stugren, B.

    1985-01-01

    Analysis of geographical distribution and comparative morphology in Vipera ursinii from Romania leads to the following results: 1. The population from Fînaţele Clujului, which does not exist anymore, belonged to the subspecies V. ursinii rakosiensis. 2. Populations from Moldavia show a mixture of

  16. Characterization of Salmonella isolated from captive and free-living snakes in Germany.

    Science.gov (United States)

    Krautwald-Junghanns, Maria-Elisabeth; Stenkat, Julia; Szabo, Istvan; Ortlieb, Falk; Blindow, Irmgard; Neul, Ann-Kathrin; Pees, Michael; Schmidt, Volker

    2013-01-01

    Reptiles are well-known reservoirs of Salmonella spp. and cases of reptile-associated salmonellosis (RAS) are increasing since reptiles are becoming more popular as pets. In the present study, the presence, distribution and prevalence of serovars of Salmonella was investigated in captive snakes (n = 87) and in free-living snakes (n = 87) in Germany. A total of 43 S. enterica-isolates were recovered from organ samples and cloacal swabs, predominantly belonging to the subspecies diarizonae (IIIb) (n = 27), enterica (I) (n = 7) and houtenae (IV) (n = 6). S. enterica subsp. enterica (I) serovar Paratyphi B (n = 4) and S. enterica subsp. diarizonae (IIIb) serovar 47:l,v:z (n = 3) were the most frequently isolated serotypes. Nevertheless, the fact that most serotypes were only represented by a single isolate points out the high diversity of Salmonella present among snakes. Salmonella enterica subsp. diarizonae (IIIb) serotype 40:i:z53, which was isolated twice from two free-living Eurasian adders (Vipera berus) captured at different locations, has not been previously described. Our results confirm the role of both free-living and captive snakes as reservoirs of S. enterica in Germany.

  17. Reproductive Disorders in Snakes.

    Science.gov (United States)

    Di Girolamo, Nicola; Selleri, Paolo

    2017-05-01

    Reproduction of snakes is one of the challenging aspects of herpetology medicine. Due to the complexity of reproduction, several disorders may present before, during, or after this process. This article describes the physical examination, and radiographic, ultrasonographic, and endoscopic findings associated with reproductive disorders in snakes. Surgical techniques used to resolve reproductive disorders in snakes are described. Finally, common reproductive disorders in snakes are individually discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Dangerous snakes, deadly snakes and medically important snakes.

    Science.gov (United States)

    Silva, Anjana

    2013-10-07

    This correspondence argues that the dangerousness of a venomous snake species is not solely determined by the venom characteristics or the lethality of the snake, and recognizes that medical importance comprises a key variable as well. The medical importance of a snake is determined by several factors - including frequency of medical attention after a bite, local or systemic envenomation provoked by the bite, fatal bites, long term consequences, availability of antivenom therapy as well as the size of the population at risk - that may vary from one region to another.

  19. Resembling a viper: implications of mimicry for conservation of the endangered smooth snake.

    Science.gov (United States)

    Valkonen, Janne K; Mappes, Johanna

    2014-12-01

    The phenomenon of Batesian mimicry, where a palatable animal gains protection against predation by resembling an unpalatable model, has been a core interest of evolutionary biologists for 150 years. An extensive range of studies has focused on revealing mechanistic aspects of mimicry (shared education and generalization of predators) and the evolutionary dynamics of mimicry systems (co-operation vs. conflict) and revealed that protective mimicry is widespread and is important for individual fitness. However, according to our knowledge, there are no case studies where mimicry theories have been applied to conservation of mimetic species. Theoretically, mimicry affects, for example, frequency dependency of predator avoidance learning and human induced mortality. We examined the case of the protected, endangered, nonvenomous smooth snake (Coronella austriaca) that mimics the nonprotected venomous adder (Vipera berus), both of which occur in the Åland archipelago, Finland. To quantify the added predation risk on smooth snakes caused by the rarity of vipers, we calculated risk estimates from experimental data. Resemblance of vipers enhances survival of smooth snakes against bird predation because many predators avoid touching venomous vipers. Mimetic resemblance is however disadvantageous against human predators, who kill venomous vipers and accidentally kill endangered, protected smooth snakes. We found that the effective population size of the adders in Åland is very low relative to its smooth snake mimic (28.93 and 41.35, respectively).Because Batesian mimicry is advantageous for the mimic only if model species exist in sufficiently high numbers, it is likely that the conservation program for smooth snakes will fail if adders continue to be destroyed. Understanding the population consequences of mimetic species may be crucial to the success of endangered species conservation. We suggest that when a Batesian mimic requires protection, conservation planners should

  20. On the issue of taxonomical status of steppe viper (Vipera renardi in Right-bank Ukraine

    Directory of Open Access Journals (Sweden)

    A. L. Baybuz

    2011-07-01

    Full Text Available Data on morphologic variability of the steppe viper in the Kirovograd region (Right-bank Ukraine are given firstly. Tentative estimation of the similaritylevel of the local population and the populations from the Left-bank Ukraine and the Crimea was carried out using methods of the multivariate statistics. Morphological data in line with the results of mitochondrial DNA analysis show that the population in the Kirovograd region belongs to widespread Eurasian species Vipera renardiand morphologically most close to the original populations of the lowland Crimea, Sivash and Forest-Steppe of the Left-bank Ukraine. This could indicate the complicated history of the Right-bank Ukraine colonization by the steppe viper and possible influence of environmental conditions on the vipers’ morphology

  1. Inhibition of nicotinic acetylcholine receptors, a novel facet in the pleiotropic activities of snake venom phospholipases A2.

    Directory of Open Access Journals (Sweden)

    Catherine A Vulfius

    Full Text Available Phospholipases A2 represent the most abundant family of snake venom proteins. They manifest an array of biological activities, which is constantly expanding. We have recently shown that a protein bitanarin, isolated from the venom of the puff adder Bitis arietans and possessing high phospholipolytic activity, interacts with different types of nicotinic acetylcholine receptors and with the acetylcholine-binding protein. To check if this property is characteristic to all venom phospholipases A2, we have studied the capability of these enzymes from other snakes to block the responses of Lymnaea stagnalis neurons to acetylcholine or cytisine and to inhibit α-bungarotoxin binding to nicotinic acetylcholine receptors and acetylcholine-binding proteins. Here we present the evidence that phospholipases A2 from venoms of vipers Vipera ursinii and V. nikolskii, cobra Naja kaouthia, and krait Bungarus fasciatus from different snake families suppress the acetylcholine- or cytisine-elicited currents in L. stagnalis neurons and compete with α-bungarotoxin for binding to muscle- and neuronal α7-types of nicotinic acetylcholine receptor, as well as to acetylcholine-binding proteins. As the phospholipase A2 content in venoms is quite high, under some conditions the activity found may contribute to the deleterious venom effects. The results obtained suggest that the ability to interact with nicotinic acetylcholine receptors may be a general property of snake venom phospholipases A2, which add a new target to the numerous activities of these enzymes.

  2. Individual Growth Rates of Nikolsky’s Viper, Vipera berus nikolskii (Squamata, Viperidae

    Directory of Open Access Journals (Sweden)

    Bondarenko Z. S.

    2016-02-01

    Full Text Available Capture-mark-recapture data was used to infer growth rates of the Nikolsky’s viper, Vipera berus nikolskii (Vedmederja, Grubant et Rudaeva, 1986, in the Eastern Ukraine. We have found that growth rate is negatively correlated with age. The difference in growth rates before maturation is not significant between different sexes. Growth rates decrease rapidly after maturation in males and females, however adult males retain significantly higher average growth rates. There is large dispersion of growth rates in the group of adult females, which is caused, probably, by alteration of complete arrest of growth in the years with reproduction and more intensive growth in the years without it. Asymptotic snout-ventral length estimated after Von Bertalanffy model was 680 mm in females and 630 mm in males. Females mature after fifth and males mature after fourth hibernation. The larger females in vipers can not be the result of higher growth rates in females, but are the outcome of a combination of other factors including different maturation time and size (older and being larger, and, perhaps, longer life span due to lower mortality. Growth rates of the Nikolsky’s viper in the nature are higher than in other species in the group of small Eurasian vipers.

  3. Vipera russelli venom-induced oxidative stress and hematological alterations: amelioration by crocin a dietary colorant.

    Science.gov (United States)

    Sebastin Santhosh, M; Hemshekhar, M; Thushara, R M; Devaraja, S; Kemparaju, K; Girish, K S

    2013-01-01

    Snakebite is a serious medical and socio-economic problem affecting the healthy individuals and agricultural and farming populations worldwide. In India, Vipera russelli snakebite is common, ensuing high morbidity and mortality. The venom components persuade multifactorial stress phenomenon and alter the physiological setting by causing disruption of the blood cells and vital organs. The present study demonstrates the anti-ophidian property of Crocin (Crocus sativus), a potent antioxidant against viper venom-induced oxidative stress. The in vivo oxidative damage induced by venom was clearly evidenced by the increased oxidative stress markers and antioxidant enzymes/molecules along with the proinflammatory cytokines including IL-1β, TNF-α and IL-6. Furthermore, venom depleted the hemoglobin, hematocrit, mean corpuscular volume and platelet count in experimental animals. Crocin ameliorated the venom-induced oxidative stress, hematological alteration and proinflammatory cytokine levels. At present, administration of antivenom is an effective therapy against systemic toxicity, but it offers no protection against the rapidly spreading oxidative damage and infiltration of pro-inflammatory mediators. These pathologies will continue even after antivenom administration. Hence, a long-term auxiliary therapy is required to treat secondary as well as neglected complications of snakebite. Copyright © 2012 John Wiley & Sons, Ltd.

  4. Homicidal Snake Bite in Children.

    Science.gov (United States)

    Paulis, Melad G; Faheem, Ayman L

    2016-03-01

    Snake bites are common in many regions of the world. Snake envenomation is relatively uncommon in Egypt; such unfortunate events usually attract much publicity. Snake bite is almost only accidental, occurring in urban areas and desert. Few cases were reported to commit suicide by snake. Homicidal snake poisoning is so rare. It was known in ancient world by executing capital punishment by throwing the victim into a pit full of snakes. Another way was to ask the victim to put his hand inside a small basket harboring a deadly snake. Killing a victim by direct snake bite is so rare. There was one reported case where an old couple was killed by snake bite. Here is the first reported case of killing three children by snake bite. It appeared that the diagnosis of such cases is so difficult and depended mainly on the circumstantial evidences. © 2015 American Academy of Forensic Sciences.

  5. [Evidence of snakes in urban areas. Analysis of cases in the province of Cuneo and public health issues].

    Science.gov (United States)

    Dutto, M; Lonati, D; Goyffon, M

    2012-01-01

    In this paper the authors analyse the cases of intrusion of snakes into urban environments in southern Piedmont (province of Cuneo) in the years 2010-2012 (up to may). In the study period there were 83 cases of intrusions in urban and domestic areas, mostly due to native harmless species (97.6%), while in 2.4% (n=2) of the cases alien species were responsible, and in 4.8% (n=4) poisonous native species were involved (Vipera aspis). The incidence of bites after a domestic intrusion is found to be 6% (n=5). All bites have resulted in loco-regional minor symptoms and occurred as a result of an accidental contact. In order to limit the risk of poisoning, the authors recommend the intrusions to be handled by properly trained personnel, since it can never be ruled out the presence of dangerous alien species on the national territory.

  6. Snake evolution and prospecting of snake venom

    NARCIS (Netherlands)

    Vonk, Freek Jacobus

    2012-01-01

    in this thesis I have shown that snakes have undergone multiple changes in their genome and embryonic development that has provided them with the variation to which natural selection could act. This thesis provides evidence for the variable mechanisms of venom gene evolution, which presumably is

  7. Evaluation of the lethal potency of scorpion and snake venoms and comparison between intraperitoneal and intravenous injection routes.

    Science.gov (United States)

    Oukkache, Naoual; El Jaoudi, Rachid; Ghalim, Noreddine; Chgoury, Fatima; Bouhaouala, Balkiss; Mdaghri, Naima El; Sabatier, Jean-Marc

    2014-06-12

    Scorpion stings and snake bites are major health hazards that lead to suffering of victims and high mortality. Thousands of injuries associated with such stings and bites of venomous animals occur every year worldwide. In North Africa, more than 100,000 scorpion stings and snake bites are reported annually. An appropriate determination of the 50% lethal doses (LD₅₀) of scorpion and snake venoms appears to be an important step to assess (and compare) venom toxic activity. Such LD₅₀ values are also commonly used to evaluate the neutralizing capacity of specific anti-venom batches. In the present work, we determined experimentally the LD₅₀ values of reference scorpion and snake venoms in Swiss mice, and evaluated the influence of two main venom injection routes (i.e., intraperitoneal (IP) versus intravenous (IV)). The analysis of experimental LD₅₀ values obtained with three collected scorpion venoms indicates that Androctonus mauretanicus (Am) is intrinsically more toxic than Androctonus australis hector (Aah) species, whereas the latter is more toxic than Buthus occitanus (Bo). Similar analysis of three representative snake venoms of the Viperidae family shows that Cerastes cerastes (Cc) is more toxic than either Bitis arietans (Ba) or Macrovipera lebetina (Ml) species. Interestingly, the venom of Elapidae cobra snake Naja haje (Nh) is far more toxic than viper venoms Cc, Ml and Ba, in agreement with the known severity of cobra-related envenomation. Also, our data showed that viper venoms are about three-times less toxic when injected IP as compared to IV, distinct from cobra venom Nh which exhibited a similar toxicity when injected IP or IV. Overall, this study clearly highlights the usefulness of procedure standardization, especially regarding the administration route, for evaluating the relative toxicity of individual animal venoms. It also evidenced a marked difference in lethal activity between venoms of cobra and vipers, which, apart from the

  8. Evaluation of the Lethal Potency of Scorpion and Snake Venoms and Comparison between Intraperitoneal and Intravenous Injection Routes

    Directory of Open Access Journals (Sweden)

    Naoual Oukkache

    2014-06-01

    Full Text Available Scorpion stings and snake bites are major health hazards that lead to suffering of victims and high mortality. Thousands of injuries associated with such stings and bites of venomous animals occur every year worldwide. In North Africa, more than 100,000 scorpion stings and snake bites are reported annually. An appropriate determination of the 50% lethal doses (LD50 of scorpion and snake venoms appears to be an important step to assess (and compare venom toxic activity. Such LD50 values are also commonly used to evaluate the neutralizing capacity of specific anti-venom batches. In the present work, we determined experimentally the LD50 values of reference scorpion and snake venoms in Swiss mice, and evaluated the influence of two main venom injection routes (i.e., intraperitoneal (IP versus intravenous (IV. The analysis of experimental LD50 values obtained with three collected scorpion venoms indicates that Androctonus mauretanicus (Am is intrinsically more toxic than Androctonus australis hector (Aah species, whereas the latter is more toxic than Buthus occitanus (Bo. Similar analysis of three representative snake venoms of the Viperidae family shows that Cerastes cerastes (Cc is more toxic than either Bitis arietans (Ba or Macrovipera lebetina (Ml species. Interestingly, the venom of Elapidae cobra snake Naja haje (Nh is far more toxic than viper venoms Cc, Ml and Ba, in agreement with the known severity of cobra-related envenomation. Also, our data showed that viper venoms are about three-times less toxic when injected IP as compared to IV, distinct from cobra venom Nh which exhibited a similar toxicity when injected IP or IV. Overall, this study clearly highlights the usefulness of procedure standardization, especially regarding the administration route, for evaluating the relative toxicity of individual animal venoms. It also evidenced a marked difference in lethal activity between venoms of cobra and vipers, which, apart from the nature of

  9. Evaluation of the Lethal Potency of Scorpion and Snake Venoms and Comparison between Intraperitoneal and Intravenous Injection Routes

    Science.gov (United States)

    Oukkache, Naoual; Jaoudi, Rachid El; Ghalim, Noreddine; Chgoury, Fatima; Bouhaouala, Balkiss; Mdaghri, Naima El; Sabatier, Jean-Marc

    2014-01-01

    Scorpion stings and snake bites are major health hazards that lead to suffering of victims and high mortality. Thousands of injuries associated with such stings and bites of venomous animals occur every year worldwide. In North Africa, more than 100,000 scorpion stings and snake bites are reported annually. An appropriate determination of the 50% lethal doses (LD50) of scorpion and snake venoms appears to be an important step to assess (and compare) venom toxic activity. Such LD50 values are also commonly used to evaluate the neutralizing capacity of specific anti-venom batches. In the present work, we determined experimentally the LD50 values of reference scorpion and snake venoms in Swiss mice, and evaluated the influence of two main venom injection routes (i.e., intraperitoneal (IP) versus intravenous (IV)). The analysis of experimental LD50 values obtained with three collected scorpion venoms indicates that Androctonus mauretanicus (Am) is intrinsically more toxic than Androctonus australis hector (Aah) species, whereas the latter is more toxic than Buthus occitanus (Bo). Similar analysis of three representative snake venoms of the Viperidae family shows that Cerastes cerastes (Cc) is more toxic than either Bitis arietans (Ba) or Macrovipera lebetina (Ml) species. Interestingly, the venom of Elapidae cobra snake Naja haje (Nh) is far more toxic than viper venoms Cc, Ml and Ba, in agreement with the known severity of cobra-related envenomation. Also, our data showed that viper venoms are about three-times less toxic when injected IP as compared to IV, distinct from cobra venom Nh which exhibited a similar toxicity when injected IP or IV. Overall, this study clearly highlights the usefulness of procedure standardization, especially regarding the administration route, for evaluating the relative toxicity of individual animal venoms. It also evidenced a marked difference in lethal activity between venoms of cobra and vipers, which, apart from the nature of toxins

  10. 50 CFR 226.205 - Critical habitat for Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River...

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Critical habitat for Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. 226.205 Section... Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook...

  11. The Mongwande Snake Cult

    OpenAIRE

    Moen, Sveinung

    2005-01-01

    Moen's work is one in a succession of recent studies of African traditions of knowledge, facing today's process of modernisation. The Mongwande snake cult is an example of how such traditions have survived intense influence from the modern schools and Christian mission. In the problematic situation of today it seems that these traditions are going through a revitalisation. The snake cult of the Mongwande is not a vanishing tradition, everything indicates that it has preserved its vitality and...

  12. Nuove segnalazioni di Zootoca vivipara Jaquin e di Vipera berus Linnaeus, in Piemonte, Italia nord-occidentale (Novitates Herpetologicae Pedemontanae II

    Directory of Open Access Journals (Sweden)

    Samuele Ghielmi

    2006-01-01

    Full Text Available Vengono forniti nuovi dati distributivi di Zootoca vivipara e di Vipera berus in Piemonte (Italia nordoccidentale. La prima viene segnalata nelle valli Bognanco (VB, Sessera (BI, Mastallone (VC, Rimella (VC e Strona (VB. Il Marasso viene invece segnalato per le valli Sorba (VC e Strona (VB. I nuovi dati distributivi vengono commentati brevemente.

  13. Heterodimeric neurotoxic phospholipases A2--the first proteins from venom of recently established species Vipera nikolskii: implication of venom composition in viper systematics.

    Science.gov (United States)

    Ramazanova, Anna S; Zavada, Larisa L; Starkov, Vladislav G; Kovyazina, Irina V; Subbotina, Tatyana F; Kostyukhina, Ekaterina E; Dementieva, Irina N; Ovchinnikova, Tatiana V; Utkin, Yuri N

    2008-03-15

    For the first time the venom of recently established viper species Vipera nikolskii was fractionated and two heterodimeric phospholipases A(2) (HDP-1 and HDP-2) were isolated. Isolation of HDP-1 and HDP-2 is the first indication of the presence of two heterodimeric phospholipases A(2) in the venom of one viper species. When tested on the frog neuromuscular junction, isolated proteins affected neuromuscular transmission acting presynaptically. Using RP-HPLC, each heterodimer was separated into two monomeric subunits: basic phospholipase A(2) (HDP-1P and HDP-2P) and acidic component without enzymatic activity (HDP-In). The complete primary structures of subunits were deduced from corresponding sequences of cDNAs. The determined amino acid sequences were homologous to those of vipoxin from Vipera ammodytes and vaspin from Vipera aspis. Similar proteins were not found earlier in the well-studied venom of Vipera berus, the species from which V. nikolskii was recently separated. Our finding supports at the biochemical level the correctness of the establishment of V. nikolskii as an independent species. The finding of similar proteins (HDPs and vipoxin) in geographically remote species (V. nikolskii and V. ammodytes) corroborates the hypothesis about the pre-existence of genes encoding these proteins in all true viper species and their expression under certain conditions.

  14. In vitro screening and evaluation of antivenom phytochemicals from Azima tetracantha Lam. leaves against Bungarus caeruleus and Vipera russelli.

    Science.gov (United States)

    Janardhan, Bhavya; Shrikanth, Vineetha M; Mirajkar, Kiran K; More, Sunil S

    2014-04-01

    Snakebites are considered a neglected tropical disease that affects thousands of people worldwide. Although antivenom is the only treatment available, it is associated with several side effects. As an alternative, plants have been extensively studied in order to obtain an alternative treatment. In folk medicine, Azima tetracantha Lam. is usually used to treat snakebites. The present study aims to provide a scientific explanation for the use of this plant against snakebite. The extracts of shade dried leaves of A. tetracantha were tested for in vitro inhibitory activity on toxic venom enzymes like phosphomonoesterase, phosphodiesterase, acetylcholinesterase, hyaluronidase etc. from Bungarus caeruleus and Vipera russelli venoms. The ethylacetate extract rendered a significant inhibitory effect on the phosphomonoesterase, phosphodiesterase, phospholipase A2 and acetylcholinesterase enzymes. The present study suggests that ethylacetate extract of A. tetracantha leaves possesses compounds that inhibit the activity of toxic enzymes from Bungarus caeruleus and Vipera russelli venom. Further pharmacological and in vivo studies would provide evidence that this substance may lead to a potential treatment against these venoms.

  15. Compartment Syndrome Following Snake Bite

    National Research Council Canada - National Science Library

    Dhar, Dinesh

    2015-01-01

    .... The local effects of snake bite include tissue necrosis, edema, and compartment syndrome. Patients may also be left with permanent physical deformities due to residual sequelae of the snake bite...

  16. Strike Back Against Snake Bites

    Science.gov (United States)

    ... gov/news/fullstory_166748.html Strike Back Against Snake Bites Expert advice on what to do if ... News) -- With summer comes a higher risk of snake bites, but emergency doctors have some advice on ...

  17. Snakes: An Integrated Unit Plan.

    Science.gov (United States)

    Lawrence, Lisa

    This document presents an integrated unit plan on snakes targeting second grade students. Objectives of the unit include developing concepts of living things, understanding the contribution and importance of snakes to the environment, and making connections between different disciplines. The unit integrates the topic of snakes into the areas of…

  18. North American Snake Envenomation.

    Science.gov (United States)

    Corbett, Bryan; Clark, Richard F

    2017-05-01

    Native US snakes that produce clinically significant envenomation can be divided into 2 groups, crotalids and elapids. The crotalids include rattlesnakes, cottonmouths, and copperheads. Crotalid envenomation can result in significant local tissue damage as well as thrombocytopenia and coagulopathy. Rarely are bites fatal. Native US elapids are all coral snakes that possess neurotoxic venom that can cause weakness, respiratory paralysis, and rarely death. Treatment of both types of envenomation revolves around general supportive care and antivenom administration when indicated. Previously advocated treatments, such as tourniquets, venom extraction, and bite site excision are not recommended. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Pulmonoscopy of Snakes.

    Science.gov (United States)

    Knotek, Zdenek; Jekl, Vladimir

    2015-09-01

    Pulmonoscopy is a practical diagnostic tool for investigating respiratory diseases in snakes. Two different approaches exist for pulmonoscopy, tracheal and transcutaneous. The access to the proximal or distal lung is limited by the length and diameter of the endoscope when using the tracheal approach. The transcutaneous approach allows direct evaluation of the lung and distal trachea through the air sac. Both of the methods are safe, and specific contraindications for pulmonoscopy in snakes are not known except for any anesthesia contraindication. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Snow snake performance monitoring.

    Science.gov (United States)

    2008-12-01

    A recent study, Three-Dimensional Roughness Elements for Snow Retention (FHWA-WY-06/04F) (Tabler 2006), demonstrated : positive evidence for the effectiveness of Snow Snakes, a new type of snow fence suitable for use within the highway right-of...

  1. Where Galactic Snakes Live

    Science.gov (United States)

    2006-01-01

    This infrared image from NASA's Spitzer Space Telescope shows what astronomers are referring to as a 'snake' (upper left) and its surrounding stormy environment. The sinuous object is actually the core of a thick, sooty cloud large enough to swallow dozens of solar systems. In fact, astronomers say the 'snake's belly' may be harboring beastly stars in the process of forming. The galactic creepy crawler to the right of the snake is another thick cloud core, in which additional burgeoning massive stars might be lurking. The colorful regions below the two cloud cores are less dense cloud material, in which dust has been heated by starlight and glows with infrared light. Yellow and orange dots throughout the image are monstrous developing stars; the red star on the 'belly' of the snake is 20 to 50 times as massive as our sun. The blue dots are foreground stars. The red ball at the bottom left is a 'supernova remnant,' the remains of massive star that died in a fiery blast. Astronomers speculate that radiation and winds from the star before it died, in addition to a shock wave created when it exploded, might have played a role in creating the snake. Spitzer was able to spot the two black cloud cores using its heat-seeking infrared vision. The objects are hiding in the dusty plane of our Milky Way galaxy, invisible to optical telescopes. Because their heat, or infrared light, can sneak through the dust, they first showed up in infrared images from past missions. The cloud cores are so thick with dust that if you were to somehow transport yourself into the middle of them, you would see nothing but black, not even a star in the sky. Now, that's spooky! Spitzer's new view of the region provides the best look yet at the massive embryonic stars hiding inside the snake. Astronomers say these observations will ultimately help them better understand how massive stars form. By studying the clustering and range of masses of the stellar embryos, they hope to determine if the stars

  2. Snake Venom Metalloproteinases

    Directory of Open Access Journals (Sweden)

    Gâz Florea Şerban Andrei

    2016-03-01

    Full Text Available As more data are generated from proteome and transcriptome analysis revealing that metalloproteinases represent most of the Viperid and Colubrid venom components authors decided to describe in a short review a classification and some of the multiple activities of snake venom metalloproteinases. SVMPs are classified in three major classes (P-I, P-II and P-III classes based on the presence of various domain structures and according to their domain organization. Furthermore, P-II and P-III classes were separated in subclasses based on distinctive post-translational modifications. SVMPs are synthesized in a latent form, being activated through a Cys-switch mechanism similar to matrix metalloproteinases. Most of the metalloproteinases of the snake venom are responsible for the hemorrhagic events but also have fibrinogenolytic activity, poses apoptotic activity, activate blood coagulation factor II and X, inhibit platelet aggregation, demonstrating that SVMPs have multiple functions in addition to well-known hemorrhagic function.

  3. Exotic pet medicine I. Snakes.

    Science.gov (United States)

    Jacobson, E R

    1993-11-01

    Of the 6,000 extant species of reptiles, approximately 2500 are snakes. Several dozen species of snakes have become popular in the pet trade, and to meet the increased demand, more and more species are being bred in captivity. Along with this popularity comes the need for more sound veterinary expertise. Although much biomedical information on snakes exists in the literature and can be found in texts on reptile medicine, few reviews have tried to consolidate the literature on this subject. The purpose of this article is to bring together information on the most pertinent aspects of snake medicine and disease.

  4. Snakes Have Feelings, Too: Elements of a Camp Snake Program.

    Science.gov (United States)

    Allen, Robert Ross

    2001-01-01

    A camp snake program can help campers overcome their fear of snakes, and people cannot truly enjoy nature when they carry a phobia about any one part of it. It can also help overcome prejudice by teaching truth and respect, instilling compassion, and helping campers develop empathy. Advice on catching, handling, identifying, keeping, and feeding…

  5. \\'The snake will swallow you': supernatural snakes and the creation ...

    African Journals Online (AJOL)

    \\'The snake will swallow you': supernatural snakes and the creation of the Khotso legend. Felicity Wood. Abstract. No Abstract. Indilinga: African Journal of Indigenous Knowledge Systems (IAJIKS) Vol. 4(1) 2005: 347-359. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  6. Runaway snakes in TEXTOR-94

    NARCIS (Netherlands)

    Entrop, I.; R. Jaspers,; Cardozo, N. J. L.; Finken, K.H.

    1999-01-01

    Observations of a runaway beam confined in an island-like structure, a so-called runaway snake, are reported. The observations are made in TEXTOR-94 by measurement of synchrotron radiation emitted by these runaways. A full poloidal View allows for the study of the synchrotron pattern of the snake to

  7. Veterinary management of snake reproduction.

    Science.gov (United States)

    Stahl, Scott J

    2002-09-01

    The reptile veterinarian should approach the breeder with a comprehensive plan involving a review of proper husbandry, nutrition, record keeping, and a thorough prebreeding evaluation of the snakes. In addition, an evaluation of the reproductive strategy, assistance with confirming and monitoring gestation, and a review of potential reproductive complications will help to prepare the snake owner for a successful breeding season.

  8. Snake-Deterministic Tiling Systems

    Science.gov (United States)

    Lonati, Violetta; Pradella, Matteo

    The concept of determinism, while clear and well assessed for string languages, is still matter of research as far as picture languages are concerned. We introduce here a new kind of determinism, called snake, based on the boustrophedonic scanning strategy, that is a natural scanning strategy used by many algorithms on 2D arrays and pictures. We consider a snake-deterministic variant of tiling systems, which defines the so-called Snake-DREC class of languages. Snake-DREC properly extends the more traditional approach of diagonal-based determinism, used e.g. by deterministic tiling systems, and by online tessellation automata. Our main result is showing that the concept of snake-determinism of tiles coincides with row (or column) unambiguity.

  9. Snake bite in Nigeria.

    Science.gov (United States)

    Habib, A G; Gebi, U I; Onyemelukwe, G C

    2001-09-01

    Four families of venomous snakes are found in Nigeria--Viperidae, Elapidae, Colubridae and Actraspididae but three species carpet viper (Echis ocellatus), black-necked spitting cobra (Naja nigricollis) and puff adder (Bitis arietans), belonging to the first two families, are the most important snakes associated with envenoming in Nigeria. The incidence of bites has been reported as 497 per 100,000 population per year with a 12 percent natural mortality, with Echis ocellatus accounting for at least 66 percent in certain foci. Bites occur more often while victims were farming, herding or walking although the spitting cobra may bite victims who roll upon it in their sleep. Carpet viper venom contains a prothrombin activating procoagulant, haemorrhagin and cytolytic fractions which cause haemorrhage, incoagulable blood, shock and local reactions/ necrosis. The spitting cobra bite manifests with local tissue reaction and occassionally with bleeding from the site of bite, but no classic neurotoxic feature has been observed except following Egyptian cobra (N. haje) bites. Cardiotoxicity and renal failure may occassionally occur following bites by the carpet viper and the puff adder. In the laboratory, haematological and other features are noted and immunodiagnosis has a role in species identification. Immobilisation of the bitten limb is probably the single most important first aid measure. Antivenom should be used cautiously when indicated. As only 8.5 percent of snake bite victims attend hospitals in Nigeria, health education should be the main preventive measure, mean-while, the study of immunisation of occupationally predisposed individuals in endemic areas should be intensified. A new Fab fragment antivenom specific to Nigerian Echis ocellatus was investigated clinically, just as the local herbs-Aristolochia spp, Guiera spp and Schummaniophyton spp are investigated experimentally.

  10. Snake City North

    OpenAIRE

    Johannesson, Tomas

    2005-01-01

    SkivproduktionJonas Kullhammar Quartet with Norrbotten Big Band – Snake City North, 2005Utgiven av Moserobie music production 2005Inspelad av Göran Stegborn och Tomas JohannessonMixad av Göran StegbornMastrad av Claes PerssonGrammisnominerad till årets jazzskiva 2005Musiker:Jonas Kullhammar: Tenor SaxophoneJonas Holgersson: DrumsTorbjörn Gulz: PianoTorbjörn Zetterberg: BassNorrbotten Big Band:Trumpets: Bo Strandberg, Magnus Ekholm, Tapio MaunuvaaraTrumpet & Fluegelhorn: Dan Johansson (2,5...

  11. Natural History of Pseudoboine Snakes

    Directory of Open Access Journals (Sweden)

    Marília P. Gaiarsa

    2013-01-01

    Full Text Available Even though natural history information is crucial for answering key ecological, evolutionary, and conservation questions, basic studies are still lacking for Neotropical snakes. This study aims at contributing to the knowledge of the Neotropical tribe Pseudoboini, based on literature data, analysis of museum specimens and unpublished data. The tribe is mainly composed of moderate-sized snakes, although small and large-sized snakes also occur in the clade. Mean fecundity ranged from two (Rodriguesophis iglesiasi to 29 eggs (Clelia plumbea and the species are predominantly terrestrial and nocturnal. Most species are diet specialists and lizards are the most commonly consumed prey (found in the diet of 29 species, followed by small mammals (consumed by 20 species and snakes (consumed by 18 species. Although the tribe Pseudoboini appears to be well studied, for 15 species (32% only a small amount of information or none was available. We hope that our study can motivate research on the least known species.

  12. Analysis of the gut contents of Vipera aspis (Reptilia, Viperidae from an area of Central Italy (Tolfa Mountains, Latium: a new method to study the terrestrial small mammals / Contributo allo studio della microteriofauna di un'area dell'Italia centrale (Monti della Tolfa, Lazio mediante analisi del contenuto stomacale di Vipera aspis (Reptilia, Viperidae

    Directory of Open Access Journals (Sweden)

    Massimo Capula

    1990-07-01

    Full Text Available Abstract A preliminary study of the trophic system between terrestrial small mammals and their specialized predator, the Asp Viper (Vipera aspis, was carried out through analysis of gut contents of 62 Vipera aspis specimens from 6 localities of Tolfa Mountains (Latium, Central Italy. Two different techniques were used in order to obtain the gut contents from a living viper: (i gently pressing its belly; (ii exposing the animal at a low temperature (<8 °C. Twelve out of 18 small mammal species occurring in this area were preyed by the vipers. The number of preyed species is very similar to that observed in the pellets of Tyto alba (Aves, Strigiformes from the same area. The only apparent exception is represented by Microtus savii: this mammal was never preyed by Vipera aspis, although being one of the principal preys of Tyto alba. These data indicate that the analysis of Vipera aspis gut contents could be utilized as a method to integrate faunistic observations on terrestrial micromammals obtained with both traditional and Barn Owl pellets data. Riassunto Nel presente contributo sono stati presi in esame i dati desunti dall'analisi dei contenuti stomacali di 62 esemplari di Vipera aspis catturati in 6 diverse stazioni dei Monti della Tolfa (Lazio, Italia centrale. Tali dati sono stati confrontati con quelli esistenti sui micromammiferi della medesima area ottenuti con l'analisi dei rigetti dei rapaci notturni e con i metodi tradizionali. Le vipere esaminate hanno predato 12 delle 18 specie di micromammiferi terrestri presenti nei Monti della Tolfa. Un numero simile di specie predate è stato osservato nella stessa area con il metodo dell'analisi dei rigetti del Barbagianni (Tyto alba. Tali dati indicano che la metodologia descritta può essere utilizzata efficacemente al fine di integrare i dati faunistici sui micromammiferi

  13. Recombinant snake venom prothrombin activators

    OpenAIRE

    L?vgren, Ann

    2012-01-01

    Three prothrombin activators; ecarin, which was originally isolated from the venom of the saw-scaled viper Echis carinatus, trocarin from the rough-scaled snake Tropidechis carinatus, and oscutarin from the Taipan snake Oxyuranus scutellatus, were expressed in mammalian cells with the purpose to obtain recombinant prothrombin activators that could be used to convert prothrombin to thrombin. We have previously reported that recombinant ecarin can efficiently generate thrombin without the need ...

  14. Varespladib (LY315920 Appears to Be a Potent, Broad-Spectrum, Inhibitor of Snake Venom Phospholipase A2 and a Possible Pre-Referral Treatment for Envenomation

    Directory of Open Access Journals (Sweden)

    Matthew Lewin

    2016-08-01

    Full Text Available Snakebite remains a neglected medical problem of the developing world with up to 125,000 deaths each year despite more than a century of calls to improve snakebite prevention and care. An estimated 75% of fatalities from snakebite occur outside the hospital setting. Because phospholipase A2 (PLA2 activity is an important component of venom toxicity, we sought candidate PLA2 inhibitors by directly testing drugs. Surprisingly, varespladib and its orally bioavailable prodrug, methyl-varespladib showed high-level secretory PLA2 (sPLA2 inhibition at nanomolar and picomolar concentrations against 28 medically important snake venoms from six continents. In vivo proof-of-concept studies with varespladib had striking survival benefit against lethal doses of Micrurus fulvius and Vipera berus venom, and suppressed venom-induced sPLA2 activity in rats challenged with 100% lethal doses of M. fulvius venom. Rapid development and deployment of a broad-spectrum PLA2 inhibitor alone or in combination with other small molecule inhibitors of snake toxins (e.g., metalloproteases could fill the critical therapeutic gap spanning pre-referral and hospital setting. Lower barriers for clinical testing of safety tested, repurposed small molecule therapeutics are a potentially economical and effective path forward to fill the pre-referral gap in the setting of snakebite.

  15. Cutaneous Chromatophoromas in Captive Snakes.

    Science.gov (United States)

    Muñoz-Gutiérrez, J F; Garner, M M; Kiupel, M

    2016-11-01

    Chromatophoromas are neoplasms arising from pigment-bearing cells (chromatophores) of the dermis. While isolated cases have been reported in the literature, the prevalence and biological behavior of chromatophoromas in snakes are unknown. Forty-two chromatophoromas were identified among 4663 submissions (0.9%) to a private diagnostic laboratory in a 16-year period. The most commonly affected snakes were colubrids (23 cases, 55%) and vipers (8 cases, 19%). The San Francisco garter snake was the most commonly affected species (6 cases; 14% of all affected snake species and 3.7% of all garter snake submissions). No sex predilection was found. The age of 28 snakes ranged from 5 to 27 years. Single cutaneous chromatophoromas were most commonly observed and presented as pigmented cutaneous masses or plaques along any body segment. Euthanasia or death due to progressive neoplastic disease or metastasis was reported in 8 (19%) and 4 (10%) cases, respectively. The survival time of 4 animals ranged from 4 to 36 months. Microscopically, xanthophoromas, iridophoromas, melanocytic neoplasms, and mixed chromatophoromas were identified, with melanocytic neoplasms being most common. Microscopic examination alone was generally sufficient for the diagnosis of chromatophoroma, but immunohistochemistry for S-100 and PNL-2 may be helpful for diagnosing poorly pigmented cases. Moderate to marked nuclear atypia appears to be consistently present in cutaneous chromatophoromas with a high risk of metastasis, while mitotic count, lymphatic invasion, the level of infiltration, and the degree of pigmentation or ulceration were not reliable predictors of metastasis. © The Author(s) 2016.

  16. Ten years of snakebites in Iran.

    Science.gov (United States)

    Dehghani, Rouhullah; Fathi, Behrooz; Shahi, Morteza Panjeh; Jazayeri, Mehrdad

    2014-11-01

    Many species of venomous snakes are found in Iran. The most medically important species which are responsible for the most snakebite incidents in Iran belong to the Viperidae family, including Vipera lebetina, Echis carinatus, Pseudocerastes persicus, Vipera albicornuta and the Elapidae family, especially Naja naja oxiana. At least one kind of venomous snake is found in each of the 31 provinces, and many provinces have more than one venomous species. As a result, snakebite is a considerable health hazard in Iran, especially in the rural area of south and south-west of Iran. A retrospective, descriptive study of snakebite in Iran during 2002-2011 was carried out in order based on data collected from medical records of bite victims admitted to hospitals and health centers. From 2002 to 2011, 53,787 cases of snake bites were reported by medical centers in Iran. The annual incidence of snake bites in 100,000 of population varied from 4.5 to 9.1 during this decade and the number of recorded deaths were about 67 cases. The highest rate of snakebite was found in provinces of south and southwest of Iran. We suggest that people, especially in the rural areas, need to be trained and educated about venomous snakes, their hazards, prevention of bite and the importance of early hospital referral and treatment of victims. Also adequate antivenins as the main life saving medicine should be made available based on the recorded numbers of victims in each area of the country. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. snake and staff symbolism and healing 1. introduction 2. the snake ...

    African Journals Online (AJOL)

    Since time immemorial the snake has been venerated as an enigmatic creature with supernatural powers. As a snake and staff symbol it is also traditionally associated with the healing arts, either as the single-snake attribute of Asclepius, or as the double- snake attribute of Hermes. In this article the mythological basis for ...

  18. Plasma concentrations of chloramphenicol in snakes.

    Science.gov (United States)

    Clark, C H; Rogers, E D; Milton, J L

    1985-12-01

    Plasma chloramphenicol concentrations after a subcutaneous injection were studied in 87 snakes of 16 different species. The biological half-life of chloramphenicol varied from 3.3 hours in the indigo snake (Drymarchon corais couperi) to 22.1 hours in the midland water snake (Nerodia sipedon). A single dosage of 50 mg of chloramphenicol/kg of body weight produced plasma concentrations greater than 5 micrograms/ml for nearly 72 hours in 2 species of water snakes (Nerodia erythrogaster, Nerodia sipedon), for 24 hours in the Burmese python (Python molurus bivittatus), and for less than 12 hours in the gray rat snake, Indigo snake, and eastern king snake (Elaphe obsoleta spiloides, Drymarchon coraise couperi, and Lampropeltis getulus getulus). A dosage of 50 mg/kg administered to water snakes every 72 hours for 18 days maintained a minimum plasma concentration of chloramphenicol between 2 and 5 micrograms/ml.

  19. The oldest known snakes from the Middle Jurassic-Lower Cretaceous provide insights on snake evolution.

    Science.gov (United States)

    Caldwell, Michael W; Nydam, Randall L; Palci, Alessandro; Apesteguía, Sebastián

    2015-01-27

    The previous oldest known fossil snakes date from ~100 million year old sediments (Upper Cretaceous) and are both morphologically and phylogenetically diverse, indicating that snakes underwent a much earlier origin and adaptive radiation. We report here on snake fossils that extend the record backwards in time by an additional ~70 million years (Middle Jurassic-Lower Cretaceous). These ancient snakes share features with fossil and modern snakes (for example, recurved teeth with labial and lingual carinae, long toothed suborbital ramus of maxillae) and with lizards (for example, pronounced subdental shelf/gutter). The paleobiogeography of these early snakes is diverse and complex, suggesting that snakes had undergone habitat differentiation and geographic radiation by the mid-Jurassic. Phylogenetic analysis of squamates recovers these early snakes in a basal polytomy with other fossil and modern snakes, where Najash rionegrina is sister to this clade. Ingroup analysis finds them in a basal position to all other snakes including Najash.

  20. 33 CFR 117.331 - Snake Creek.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Snake Creek. 117.331 Section 117.331 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.331 Snake Creek. The draw of the Snake Creek...

  1. 33 CFR 117.1058 - Snake River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Snake River. 117.1058 Section 117... OPERATION REGULATIONS Specific Requirements Washington § 117.1058 Snake River. (a) The draw of the Burlington Northern Santa Fe railroad bridge across the Snake River at mile 1.5 between Pasco and Burbank is...

  2. Coyotes Are Afraid of Little Snakes.

    Science.gov (United States)

    Weewish Tree, 1979

    1979-01-01

    Wichita tale of a contest between Coyote and Small Snake to see whose teeth are strongest. They bite each other, and soon big, strong Coyote is dead from the poisoned bite of the tiny snake. Explains why, from that time onward, coyotes have been afraid of little snakes. (DS)

  3. Molecular Identification of Cryptosporidium Species from Pet Snakes in Thailand

    OpenAIRE

    Yimming, Benjarat; Pattanatanang, Khampee; SANYATHITISEREE, PORNCHAI; Inpankaew, Tawin; KAMYINGKIRD, Ketsarin; Pinyopanuwat, Nongnuch; Chimnoi, Wissanuwat; Phasuk, Jumnongjit

    2016-01-01

    Cryptosporidium is an important pathogen causing gastrointestinal disease in snakes and is distributed worldwide. The main objectives of this study were to detect and identify Cryptosporidium species in captive snakes from exotic pet shops and snake farms in Thailand. In total, 165 fecal samples were examined from 8 snake species, boa constrictor (Boa constrictor constrictor), corn snake (Elaphe guttata), ball python (Python regius), milk snake (Lampropeltis triangulum), king snake (Lampropel...

  4. Toxin synergism in snake venoms

    DEFF Research Database (Denmark)

    Laustsen, Andreas Hougaard

    2016-01-01

    Synergism between venom toxins exists for a range of snake species. Synergism can be derived from both intermolecular interactions and supramolecular interactions between venom components, and can be the result of toxins targeting the same protein, biochemical pathway or physiological process. Few...... simple systematic tools and methods for determining the presence of synergism exist, but include co-administration of venom components and assessment of Accumulated Toxicity Scores. A better understanding of how to investigate synergism in snake venoms may help unravel strategies for developing novel...

  5. Snake venom toxins: toxicity and medicinal applications.

    Science.gov (United States)

    Chan, Yau Sang; Cheung, Randy Chi Fai; Xia, Lixin; Wong, Jack Ho; Ng, Tzi Bun; Chan, Wai Yee

    2016-07-01

    Snake venoms are complex mixtures of small molecules and peptides/proteins, and most of them display certain kinds of bioactivities. They include neurotoxic, cytotoxic, cardiotoxic, myotoxic, and many different enzymatic activities. Snake envenomation is a significant health issue as millions of snakebites are reported annually. A large number of people are injured and die due to snake venom poisoning. However, several fatal snake venom toxins have found potential uses as diagnostic tools, therapeutic agent, or drug leads. In this review, different non-enzymatically active snake venom toxins which have potential therapeutic properties such as antitumor, antimicrobial, anticoagulating, and analgesic activities will be discussed.

  6. Snake fungal disease: An emerging threat to wild snakes

    Science.gov (United States)

    Lorch, Jeffrey M.; Knowles, Susan N.; Lankton, Julia S.; Michell, Kathy; Edwards, Jaime L.; Kapfer, Joshua M.; Staffen, Richard A.; Wild, Erik R.; Schmidt, Katie Z.; Ballmann, Anne; Blodgett, Doug; Farrell, Terence M.; Glorioso, Brad M.; Last, Lisa A.; Price, Steven J.; Schuler, Krysten L.; Smith, Christopher E.; Wellehan, James F. X.; Blehert, David S.

    2016-01-01

    Since 2006, there has been a marked increase in the number of reports of severe and often fatal fungal skin infections in wild snakes in the eastern USA. The emerging condition, referred to as snake fungal disease (SFD), was initially documented in rattlesnakes, where the infections were believed to pose a risk to the viability of affected populations. The disease is caused byOphidiomyces ophiodiicola, a fungus recently split from a complex of fungi long referred to as the Chrysosporium anamorph of Nannizziopsis vriesii (CANV). Here we review the current state of knowledge about O. ophiodiicola and SFD. In addition, we provide original findings which demonstrate that O. ophiodiicola is widely distributed in eastern North America, has a broad host range, is the predominant cause of fungal skin infections in wild snakes and often causes mild infections in snakes emerging from hibernation. This new information, together with what is already available in the scientific literature, advances our knowledge of the cause, pathogenesis and ecology of SFD. However, additional research is necessary to elucidate the factors driving the emergence of this disease and develop strategies to mitigate its impacts.

  7. Snake fungal disease: an emerging threat to wild snakes.

    Science.gov (United States)

    Lorch, Jeffrey M; Knowles, Susan; Lankton, Julia S; Michell, Kathy; Edwards, Jaime L; Kapfer, Joshua M; Staffen, Richard A; Wild, Erik R; Schmidt, Katie Z; Ballmann, Anne E; Blodgett, Doug; Farrell, Terence M; Glorioso, Brad M; Last, Lisa A; Price, Steven J; Schuler, Krysten L; Smith, Christopher E; Wellehan, James F X; Blehert, David S

    2016-12-05

    Since 2006, there has been a marked increase in the number of reports of severe and often fatal fungal skin infections in wild snakes in the eastern USA. The emerging condition, referred to as snake fungal disease (SFD), was initially documented in rattlesnakes, where the infections were believed to pose a risk to the viability of affected populations. The disease is caused by Ophidiomyces ophiodiicola, a fungus recently split from a complex of fungi long referred to as the Chrysosporium anamorph of Nannizziopsis vriesii (CANV). Here we review the current state of knowledge about O. ophiodiicola and SFD. In addition, we provide original findings which demonstrate that O. ophiodiicola is widely distributed in eastern North America, has a broad host range, is the predominant cause of fungal skin infections in wild snakes and often causes mild infections in snakes emerging from hibernation. This new information, together with what is already available in the scientific literature, advances our knowledge of the cause, pathogenesis and ecology of SFD. However, additional research is necessary to elucidate the factors driving the emergence of this disease and develop strategies to mitigate its impacts.This article is part of the themed issue 'Tackling emerging fungal threats to animal health, food security and ecosystem resilience'. © 2016 The Author(s).

  8. The effect of a single dose of prednisolone in dogs envenomated by Vipera berus--a randomized, double-blind, placebo-controlled clinical trial.

    Science.gov (United States)

    Brandeker, Erika; Hillström, Anna; Hanås, Sofia; Hagman, Ragnvi; Holst, Bodil Ström

    2015-02-26

    Treatment with glucocorticoids after snakebite in dogs is controversial and randomized clinical studies are missing. The objective of this study was to investigate the effect of a single dose of prednisolone in dogs envenomated by Vipera berus in a double-blind placebo-controlled study, after exclusion of dogs treated with antivenom. The two treatment groups were compared regarding clinical status and clinicopathological test results. A total of 75 dogs bitten by Vipera berus within the previous 24 hours were included. Clinical assessment, blood sampling and measurement of the bitten body part were done at admission (Day 1), after 24 hours (Day 2) and at a re-examination (Re-exam) after 10-28 days. Dogs were given prednisolone 1 mg/kg bodyweight (PRED) or saline (PLACEBO) subcutaneously in a randomized, double-blind clinical trial. Dogs were examined clinically and mental status and extent of edema were described. Furthermore, appetite, vomiting, diarrhea, cardiac arrhythmia and death were recorded. Concentrations of C-reactive protein (CRP) and high sensitivity cardiac Troponin I (cTnI), hematology variables and Prothrombin time (PT) were determined. Systemic inflammation was defined as present if CRP > 35 mg/l. None of the dogs died during the study period. The mental status was reduced in 60/75 (80%) of dogs on Day 1, compared to 19/75 (25%) on Day 2. The proportion of dogs with no or only mild edema increased significantly from Day 1 to Day 2. About one-third of the dogs developed gastrointestinal signs during the study period. Cardiac arrhythmia was uncommon. Clinicopathological changes included increased total leucocyte count, CRP and troponin concentration on Day 2. The cTnI concentration was increased in dogs with systemic inflammation, compared to dogs without systemic inflammation. A single dose of prednisolone did not significantly affect any of the clinical or clinicopathological parameters studied, except for a higher monocyte count on Day 2 in

  9. Snake Robots Modelling, Mechatronics, and Control

    CERN Document Server

    Liljebäck, Pål; Stavdahl, Øyvind; Gravdahl, Jan Tommy

    2013-01-01

    Snake Robots is a novel treatment of theoretical and practical topics related to snake robots: robotic mechanisms designed to move like biological snakes and able to operate in challenging environments in which human presence is either undesirable or impossible. Future applications of such robots include search and rescue, inspection and maintenance, and subsea operations. Locomotion in unstructured environments is a focus for this book. The text targets the disparate muddle of approaches to modelling, development and control of snake robots in current literature, giving a unified presentation of recent research results on snake robot locomotion to increase the reader’s basic understanding of these mechanisms and their motion dynamics and clarify the state of the art in the field. The book is a complete treatment of snake robotics, with topics ranging from mathematical modelling techniques, through mechatronic design and implementation, to control design strategies. The development of two snake robots is de...

  10. A description of parasites from Iranian snakes.

    Science.gov (United States)

    Nasiri, Vahid; Mobedi, Iraj; Dalimi, Abdolhossein; Mirakabadi, Abbas Zare; Ghaffarifar, Fatemeh; Teymurzadeh, Shohreh; Karimi, Gholamreza; Abdoli, Amir; Paykari, Habibollah

    2014-12-01

    Little is known of the parasitic fauna of terrestrial snakes in Iran. This study aimed to evaluate the parasitic infection rates of snakes in Iran. A total of 87 snakes belonging to eight different species, that were collected between May 2012 and September 2012 and died after the hold in captivity, under which they were kept for taking poisons, were examined for the presence of gastrointestinal and blood parasites. According to our study 12 different genera of endoparasites in 64 (73.56%) of 87 examined snakes were determined. Forty one snakes (47.12%) had gastrointestinal parasites. In prepared blood smears, it was found that in 23 (26.43%) of 87 examined snakes there are at least one hemoparasite. To our knowledge, these are the first data on the internal parasitic fauna of Iranian terrestrial snakes and our findings show a higher prevalence of these organisms among them. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Venomous Snake Bite Injuries at Kitui District Hospital | Kihiko ...

    African Journals Online (AJOL)

    Background Snake bites are a neglected public health issue in poor rural communities, and the true burden of snake bites is not known. Kitui County has a high incidence of snake bites and no functional snake bite control programs exists. Diagnostic tests for snake species identification are not available and management ...

  12. Snakes of the Guianan region

    NARCIS (Netherlands)

    Hoogmoed, M.S.

    1982-01-01

    The study of snaks from the Guianan region got an early start in 1705 when several species were pictured by Merian. As relatively large proportion of the snakes described by Linnaeus originated from Surinam. Interest for and knowledge of this group of animals steadily increased in the 18th and 19th

  13. Regina rigida (glossy crayfish snake)

    Science.gov (United States)

    David A. Steen; James A. Stiles; Sierra H. Stiles; Craig Guyer; Josh B. Pierce; D. Craig Rudolph; Lora L. Smith

    2011-01-01

    The overland movements and upland habitat use of wetland-associated reptiles has important conservation implications (Semlitsch and Bodie 2003. Conserv. BioI. 17:1219-1228). However, for many species, particularly snakes, we lack a basic understanding of spatial ecology and habitat use. Regina rigida is a poorly known species for which "observations of any kind...

  14. Snake venom metalloproteinases.

    Science.gov (United States)

    Markland, Francis S; Swenson, Stephen

    2013-02-01

    Recent proteomic analyses of snake venoms show that metalloproteinases represent major components in most of the Crotalid and Viperid venoms. In this chapter we discuss the multiple activities of the SVMPs. In addition to hemorrhagic activity, members of the SVMP family also have fibrin(ogen)olytic activity, act as prothrombin activators, activate blood coagulation factor X, possess apoptotic activity, inhibit platelet aggregation, are pro-inflammatory and inactivate blood serine proteinase inhibitors. Clearly the SVMPs have multiple functions in addition to their well-known hemorrhagic activity. The realization that there are structural variations in the SVMPs and the early studies that led to their classification represents an important event in our understanding of the structural forms of the SVMPs. The SVMPs were subdivided into the P-I, P-II and P-III protein classes. The noticeable characteristic that distinguished the different classes was their size (molecular weight) differences and domain structure: Class I (P-I), the small SVMPs, have molecular masses of 20-30 kDa, contain only a pro domain and the proteinase domain; Class II (P-II), the medium size SVMPs, molecular masses of 30-60 kDa, contain the pro domain, proteinase domain and disintegrin domain; Class III (P-III), the large SVMPs, have molecular masses of 60-100 kDa, contain pro, proteinase, disintegrin-like and cysteine-rich domain structure. Another significant advance in the SVMP field was the characterization of the crystal structure of the first P-I class SVMP. The structures of other P-I SVMPs soon followed and the structures of P-III SVMPs have also been determined. The active site of the metalloproteinase domain has a consensus HEXXHXXGXXHD sequence and a Met-turn. The "Met-turn" structure contains a conserved Met residue that forms a hydrophobic basement for the three zinc-binding histidines in the consensus sequence. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Lebein, a snake venom disintegrin, suppresses human colon cancer cells proliferation and tumor-induced angiogenesis through cell cycle arrest, apoptosis induction and inhibition of VEGF expression.

    Science.gov (United States)

    Zakraoui, Ons; Marcinkiewicz, Cezary; Aloui, Zohra; Othman, Houcemeddine; Grépin, Renaud; Haoues, Meriam; Essafi, Makram; Srairi-Abid, Najet; Gasmi, Ammar; Karoui, Habib; Pagès, Gilles; Essafi-Benkhadir, Khadija

    2017-01-01

    Lebein, is an heterodimeric disintegrin isolated from Macrovipera lebetina snake venom that was previously characterized as an inhibitor of ADP-induced platelet aggregation. In this study, we investigated the effect of Lebein on the p53-dependent growth of human colon adenocarcinoma cell lines. We found that Lebein significantly inhibited LS174 (p53wt), HCT116 (p53wt), and HT29 (p53mut) colon cancer cell viability by inducing cell cycle arrest through the modulation of expression levels of the tumor suppression factor p53, cell cycle regulating proteins cyclin D1, CDK2, CDK4, retinoblastoma (Rb), CDK1, and cyclin-dependent kinase inhibitors p21 and p27. Interestingly, Lebein-induced apoptosis of colon cancer cells was dependent on their p53 status. Thus, in LS174 cells, cell death was associated with PARP cleavage and the activation of caspases 3 and 8 while in HCT116 cells, Lebein induced caspase-independent apoptosis through increased expression of apoptosis inducing factor (AIF). In LS174 cells, Lebein triggers the activation of the MAPK ERK1/2 pathway through induction of reactive oxygen species (ROS). It also decreased cell adhesion and migration to fibronectin through down regulation of α5β1 integrin. Moreover, Lebein significantly reduced the expression of two angiogenesis stimulators, Vascular Endothelial Growth Factor (VEGF) and Neuropilin 1 (NRP1). It inhibited the VEGF-induced neovascularization process in the quail embryonic CAM system and blocked the development of human colon adenocarcinoma in nude mice. Overall, our work indicates that Lebein may be useful to design a new therapy against colon cancer. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  16. The Study on the Snake by TOXICON

    Directory of Open Access Journals (Sweden)

    Sung-wook Kim

    2003-06-01

    Full Text Available The study was carried out to investigate the researches of Snake which was published papers in the TOXICON(1990-2.000, one of the most famous Journal of toxicology. And the results were as follows: 1. The number related with Snake is 195papers. 2. There were great papers related wih Cobra, and next is Tigris, Viper, etc. 3. There were great papers related wih protein in the composition of snake venom. 4. There were great papers related wih neurotoxin in the research of poisonous character. 5. There were great papers related wih Viper according to the anticoagulation. 6. Eight papers were published to study the immune response of snake venom. 7. The papers of molecular study of snake venom were seven. 8. The papers of anti-snake venom study were three.

  17. Observations of Snake Resonance in RHIC

    CERN Document Server

    Bai, Mei; Lee, Shyh-Yuan; Lin, Fanglei; MacKay, William; Ptitsyn, Vadim; Roser, Thomas; Tepikian, Steven

    2005-01-01

    Siberian snakes now become essential in the polarized proton acceleration. With proper configuration of Siberian snakes, the spin precession tune of the beam becomes $\\frac{1}{2}$ which avoids all the spin depolarizing resonance. However, the enhancement of the perturbations on the spin motion can still occur when the betatron tune is near some low order fractional numbers, called snake resonances, and the beam can be depolarized when passing through the resonance. The snake resonances have been confirmed in the spin tracking calculations, and observed in RHIC with polarized proton beam. Equipped with two full Siberian snakes in each ring, RHIC provides us a perfect facility for snake resonance studies. This paper presents latest experimental results. New insights are also discussed.

  18. Snake scales, partial exposure, and the Snake Detection Theory: A human event-related potentials study

    Science.gov (United States)

    Van Strien, Jan W.; Isbell, Lynne A.

    2017-01-01

    Studies of event-related potentials in humans have established larger early posterior negativity (EPN) in response to pictures depicting snakes than to pictures depicting other creatures. Ethological research has recently shown that macaques and wild vervet monkeys respond strongly to partially exposed snake models and scale patterns on the snake skin. Here, we examined whether snake skin patterns and partially exposed snakes elicit a larger EPN in humans. In Task 1, we employed pictures with close-ups of snake skins, lizard skins, and bird plumage. In task 2, we employed pictures of partially exposed snakes, lizards, and birds. Participants watched a random rapid serial visual presentation of these pictures. The EPN was scored as the mean activity (225–300 ms after picture onset) at occipital and parieto-occipital electrodes. Consistent with previous studies, and with the Snake Detection Theory, the EPN was significantly larger for snake skin pictures than for lizard skin and bird plumage pictures, and for lizard skin pictures than for bird plumage pictures. Likewise, the EPN was larger for partially exposed snakes than for partially exposed lizards and birds. The results suggest that the EPN snake effect is partly driven by snake skin scale patterns which are otherwise rare in nature. PMID:28387376

  19. [Snake envenomation in French Guiana].

    Science.gov (United States)

    Chippaux, J P

    2002-01-01

    French Guiana is a French Overseas Department in South America. Ninety-five percent of the territory is a tropical rainforest. Its rich fauna includes seven families of snakes but only 3 are potentially venomous. Less than 12% of species and, depending on biotope, 10 to 30% of specimens collected are dangerous for humans. The annual incidence of snakebite is less than 50 bites per 100,000 inhabitants overall but increases to 600 per 100,000 for persons active in the rainforest where the risk is highest. The most common envenomation by Viperidae such as Bothrops, which is abundant throughout French Guiana, induces inflammation, necrosis and hemorrhage. Crotalus durissus, a rattlesnake living in coastal savannah, or Micrurus sp cause neuromuscular poisoning. Coral snakes are encountered throughout French Guiana, but envenomation is very rare. Antivenom therapy must be administered by the intravenous route in association with symptomatic treatment and, if necessary, resuscitation in a specialized care unit.

  20. Snake venom antibodies in Ecuadorian Indians.

    Science.gov (United States)

    Theakston, R D; Reid, H A; Larrick, J W; Kaplan, J; Yost, J A

    1981-10-01

    Serum samples from 223 Waorani Indians, a tribe in eastern Ecuador, were investigated by enzyme-linked immunosorbent assay for antibodies to snake venom. Seventy-eight per cent were positive, confirming the highest incidence and mortality from snake bite poisoning yet recorded in the world. Most samples were positive for more than one venom antibody. Antibodies were found to venoms of Bothrops viper in 60% of positive cases, of Micrurus coral snake in 21%, and of the bushmaster, Lachesis muta, in 18%. Further studies are needed to determine whether high venom-antibody levels afford protection against further snake envenoming.

  1. Snake bite in South Asia: a review

    National Research Council Canada - National Science Library

    Alirol, Emilie; Sharma, Sanjib Kumar; Bawaskar, Himmatrao Saluba; Kuch, Ulrich; Chappuis, François

    2010-01-01

    .... Despite increasing knowledge of snake venoms' composition and mode of action, good understanding of clinical features of envenoming and sufficient production of antivenom by Indian manufacturers...

  2. Experimental research of specificity of fear of snake: coral snake pattern

    OpenAIRE

    PRŮŠOVÁ, Lucie

    2013-01-01

    Due to shared coevolutionary history of snakes and primates with snakes acting as their main predators, snakes elicit fear in most of the primates, humans included. Humans are able to notice a stimulus that elicits fear, e.g., a snake, much faster. Such ability might have surely positively affected their survival in the past. In the nature, aposematic coloration acts as a warning of a dangerous prey to its predators not to devour it. The highly poisonous American coral snakes have this colora...

  3. Snake bioacoustics: toward a richer understanding of the behavioral ecology of snakes.

    Science.gov (United States)

    Young, Bruce A

    2003-09-01

    Snakes are frequently described in both popular and technical literature as either deaf or able to perceive only groundborne vibrations. Physiological studies have shown that snakes are actually most sensitive to airborne vibrations. Snakes are able to detect both airborne and groundborne vibrations using their body surface (termed somatic hearing) as well as from their inner ears. The central auditory pathways for these two modes of "hearing" remain unknown. Recent experimental evidence has shown that snakes can respond behaviorally to both airborne and groundborne vibrations. The ability of snakes to contextualize the sounds and respond with consistent predatory or defensive behaviors suggests that auditory stimuli may play a larger role in the behavioral ecology of snakes than was previously realized. Snakes produce sounds in a variety of ways, and there appear to be multiple acoustic Batesian mimicry complexes among snakes. Analyses of the proclivity for sound production and the acoustics of the sounds produced within a habitat or phylogeny specific context may provide insights into the behavioral ecology of snakes. The relatively low information content in the sounds produced by snakes suggests that these sounds are not suitable for intraspecific communication. Nevertheless, given the diversity of habitats in which snakes are found, and their dual auditory pathways, some form of intraspecific acoustic communication may exist in some species.

  4. Breaking Snake Camouflage: Humans Detect Snakes More Accurately than Other Animals under Less Discernible Visual Conditions.

    Directory of Open Access Journals (Sweden)

    Nobuyuki Kawai

    Full Text Available Humans and non-human primates are extremely sensitive to snakes as exemplified by their ability to detect pictures of snakes more quickly than those of other animals. These findings are consistent with the Snake Detection Theory, which hypothesizes that as predators, snakes were a major source of evolutionary selection that favored expansion of the visual system of primates for rapid snake detection. Many snakes use camouflage to conceal themselves from both prey and their own predators, making it very challenging to detect them. If snakes have acted as a selective pressure on primate visual systems, they should be more easily detected than other animals under difficult visual conditions. Here we tested whether humans discerned images of snakes more accurately than those of non-threatening animals (e.g., birds, cats, or fish under conditions of less perceptual information by presenting a series of degraded images with the Random Image Structure Evolution technique (interpolation of random noise. We find that participants recognize mosaic images of snakes, which were regarded as functionally equivalent to camouflage, more accurately than those of other animals under dissolved conditions. The present study supports the Snake Detection Theory by showing that humans have a visual system that accurately recognizes snakes under less discernible visual conditions.

  5. Breaking Snake Camouflage: Humans Detect Snakes More Accurately than Other Animals under Less Discernible Visual Conditions.

    Science.gov (United States)

    Kawai, Nobuyuki; He, Hongshen

    2016-01-01

    Humans and non-human primates are extremely sensitive to snakes as exemplified by their ability to detect pictures of snakes more quickly than those of other animals. These findings are consistent with the Snake Detection Theory, which hypothesizes that as predators, snakes were a major source of evolutionary selection that favored expansion of the visual system of primates for rapid snake detection. Many snakes use camouflage to conceal themselves from both prey and their own predators, making it very challenging to detect them. If snakes have acted as a selective pressure on primate visual systems, they should be more easily detected than other animals under difficult visual conditions. Here we tested whether humans discerned images of snakes more accurately than those of non-threatening animals (e.g., birds, cats, or fish) under conditions of less perceptual information by presenting a series of degraded images with the Random Image Structure Evolution technique (interpolation of random noise). We find that participants recognize mosaic images of snakes, which were regarded as functionally equivalent to camouflage, more accurately than those of other animals under dissolved conditions. The present study supports the Snake Detection Theory by showing that humans have a visual system that accurately recognizes snakes under less discernible visual conditions.

  6. 33 CFR 117.385 - Snake River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Snake River. 117.385 Section 117.385 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Idaho § 117.385 Snake River. The drawspan of the U.S. 12 bridge...

  7. Coral snake mimicry: does it occur?

    Science.gov (United States)

    Greene, H.W.; McDiarmid, R.W.

    1981-01-01

    Field observations and experimental evidence refute previous objections to the coral snake mimicry hypothesis. Concordant color pattern variation spanning hundreds of miles and several presumed venemous models strongly suggests that several harmless or mildly venemous colubrid snakes are indeed mimics of highly venemous elapids.

  8. Evolutionary stability of sex chromosomes in snakes.

    Science.gov (United States)

    Rovatsos, Michail; Vukić, Jasna; Lymberakis, Petros; Kratochvíl, Lukáš

    2015-12-22

    Amniote vertebrates possess various mechanisms of sex determination, but their variability is not equally distributed. The large evolutionary stability of sex chromosomes in viviparous mammals and birds was believed to be connected with their endothermy. However, some ectotherm lineages seem to be comparably conserved in sex determination, but previously there was a lack of molecular evidence to confirm this. Here, we document a stability of sex chromosomes in advanced snakes based on the testing of Z-specificity of genes using quantitative PCR (qPCR) across 37 snake species (our qPCR technique is suitable for molecular sexing in potentially all advanced snakes). We discovered that at least part of sex chromosomes is homologous across all families of caenophidian snakes (Acrochordidae, Xenodermatidae, Pareatidae, Viperidae, Homalopsidae, Colubridae, Elapidae and Lamprophiidae). The emergence of differentiated sex chromosomes can be dated back to about 60 Ma and preceded the extensive diversification of advanced snakes, the group with more than 3000 species. The Z-specific genes of caenophidian snakes are (pseudo)autosomal in the members of the snake families Pythonidae, Xenopeltidae, Boidae, Erycidae and Sanziniidae, as well as in outgroups with differentiated sex chromosomes such as monitor lizards, iguanas and chameleons. Along with iguanas, advanced snakes are therefore another example of ectothermic amniotes with a long-term stability of sex chromosomes comparable with endotherms. © 2015 The Author(s).

  9. Snake venom instability | Willemse | African Zoology

    African Journals Online (AJOL)

    Egyptian cobra Naja haje haje) and puffadder (Bills arietans). Considerable differences in electrophoretic characteristics were found between fresh venom and commercial venom samples from the same species of snake. These differences could be attributed partly to the instability of snake venom under conditions of drying ...

  10. On a collection of Snakes from Dehli

    NARCIS (Netherlands)

    Lidth de Jeude, van Th.W.

    1890-01-01

    During his stay in Laboean (Delili, East-Sumatra) Dr. B. Hagen, to whom the Leyden Museum is indebted for large series of mammals, birds and insects, also collected a large number of snakes, the greater part of which were sent to our Museum. Dr. Hagen took a lively interest in snakes, and being

  11. Snake Genome Sequencing: Results and Future Prospects.

    Science.gov (United States)

    Kerkkamp, Harald M I; Kini, R Manjunatha; Pospelov, Alexey S; Vonk, Freek J; Henkel, Christiaan V; Richardson, Michael K

    2016-12-01

    Snake genome sequencing is in its infancy-very much behind the progress made in sequencing the genomes of humans, model organisms and pathogens relevant to biomedical research, and agricultural species. We provide here an overview of some of the snake genome projects in progress, and discuss the biological findings, with special emphasis on toxinology, from the small number of draft snake genomes already published. We discuss the future of snake genomics, pointing out that new sequencing technologies will help overcome the problem of repetitive sequences in assembling snake genomes. Genome sequences are also likely to be valuable in examining the clustering of toxin genes on the chromosomes, in designing recombinant antivenoms and in studying the epigenetic regulation of toxin gene expression.

  12. Snake Genome Sequencing: Results and Future Prospects

    Directory of Open Access Journals (Sweden)

    Harald M. I. Kerkkamp

    2016-12-01

    Full Text Available Snake genome sequencing is in its infancy—very much behind the progress made in sequencing the genomes of humans, model organisms and pathogens relevant to biomedical research, and agricultural species. We provide here an overview of some of the snake genome projects in progress, and discuss the biological findings, with special emphasis on toxinology, from the small number of draft snake genomes already published. We discuss the future of snake genomics, pointing out that new sequencing technologies will help overcome the problem of repetitive sequences in assembling snake genomes. Genome sequences are also likely to be valuable in examining the clustering of toxin genes on the chromosomes, in designing recombinant antivenoms and in studying the epigenetic regulation of toxin gene expression.

  13. Snake Genome Sequencing: Results and Future Prospects

    Science.gov (United States)

    Kerkkamp, Harald M. I.; Kini, R. Manjunatha; Pospelov, Alexey S.; Vonk, Freek J.; Henkel, Christiaan V.; Richardson, Michael K.

    2016-01-01

    Snake genome sequencing is in its infancy—very much behind the progress made in sequencing the genomes of humans, model organisms and pathogens relevant to biomedical research, and agricultural species. We provide here an overview of some of the snake genome projects in progress, and discuss the biological findings, with special emphasis on toxinology, from the small number of draft snake genomes already published. We discuss the future of snake genomics, pointing out that new sequencing technologies will help overcome the problem of repetitive sequences in assembling snake genomes. Genome sequences are also likely to be valuable in examining the clustering of toxin genes on the chromosomes, in designing recombinant antivenoms and in studying the epigenetic regulation of toxin gene expression. PMID:27916957

  14. Snake and staff symbolism, and healing | Retief | South African ...

    African Journals Online (AJOL)

    Since time immemorial the snake has been venerated as an enigmatic creature with supernatural powers. As a snake and staff symbol it is also traditionally associated with the healing arts, either as the single-snake emblem of Asklepios, or as the double-snake emblem (caduceus) of Hermes. The mythological basis for this ...

  15. 27 CFR 9.208 - Snake River Valley.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Snake River Valley. 9.208... Snake River Valley. (a) Name. The name of the viticultural area described in this section is “Snake River Valley”. For purposes of part 4 of this chapter, “Snake River Valley” is a term of viticultural...

  16. 77 FR 10960 - Drawbridge Operation Regulation; Snake Creek, Islamorada, FL

    Science.gov (United States)

    2012-02-24

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Snake Creek, Islamorada, FL AGENCY... of Snake Creek Bridge, mile 0.5, across Snake Creek, in Islamorada, Florida. The regulation is set... Sheriff's Office has requested a temporary modification to the operating schedule of Snake Creek Bridge in...

  17. Epidemiology of Snake Bites among Selected Communities in the ...

    African Journals Online (AJOL)

    Snake is one of the major group of games feared by people in many localities because of their venoms, yet snakes are equally afraid of human beings. This balance of terror apart from affecting both man and snakes has also led to their deaths. Epidemiology of snake bites among selected communities in the enclave of ...

  18. 50 CFR Table 3 to Part 226 - Hydrologic Units Containing Critical Habitat for Snake River Sockeye Salmon and Snake River...

    Science.gov (United States)

    2010-10-01

    ... Habitat for Snake River Sockeye Salmon and Snake River Spring/Summer and Fall Chinook Salmon 3 Table 3 to... Part 226—Hydrologic Units Containing Critical Habitat for Snake River Sockeye Salmon and Snake River... Snake—Asotin 17060103 17060103 17060103 Upper Grande Ronde 17060104 Wallowa 17060105 Lower Grande Ronde...

  19. STUDY OF CLINICAL MANIFESTATIONS AND COMPLICATIONS OF HAEMOTOXIC SNAKE ENVENOMATION

    OpenAIRE

    Narasimham; Srinivasa Rao

    2015-01-01

    BACKGROUND AND OBJECTIVES: Snake bites are of major public health importance in many communities as causes of haemorrhage, other morbidity and mortality. 1 Of the 3000 species of snakes, about 500 belong to the 3 families of venomous snakes, Atr actaspididae, Elapidae and Viperidae. Estimated 15000 – 20000 people die each year from snake bite in India. 2 In tropical countries snake bite is occupational disease of farmers, plantation workers and hunters. In ...

  20. Head triangulation as anti-predatory mechanism in snakes

    OpenAIRE

    Dell'Aglio,Denise Dalbosco; Toma,Tiago Shizen Pacheco; Muelbert, Adriane Esquivel; Sacco, Anne Gomes; Tozetti,Alexandro Marques

    2012-01-01

    Anti-predator mechanisms in snakes are diverse and complex, including mimetic behavior. Some snakes triangulate their head, probably mimicking other more dangerous snakes. However, there is a lack of studies that demonstrate the effectiveness of this behavior with natural predators. The aim of this study was to verify, using artificial snakes, if snakes with triangular heads are less susceptible to attack by predators, and if predatory attack is targeted to the head of serpents. Artificial sn...

  1. Hemostatic interference of Indian king cobra (Ophiophagus hannah) Venom. Comparison with three other snake venoms of the subcontinent.

    Science.gov (United States)

    Gowtham, Yashonandana J; Kumar, M S; Girish, K S; Kemparaju, K

    2012-06-01

    Unlike Naja naja, Bungarus caeruleus, Echis carinatus, and Daboia/Vipera russellii venoms, Ophiophagus hannah venom is medically ignored in the Indian subcontinent. Being the biggest poisonous snake, O. hannah has been presumed to inject several lethal doses of venom in a single bite. Lack of therapeutic antivenom to O. hannah bite in India makes any attempt to save the victim a difficult exercise. This study was initiated to compare O. hannah venom with the above said venoms for possible interference in hemostasis. Ophiophagus hannah venom was found to actively interfere in hemostatic stages such as fibrin clot formation, platelet activation/aggregation, and fibrin clot dissolution. It decreased partial thromboplastin time (aPTT), prothrombin time (PT), and thrombin clotting time (TCT). These activities are similar to that shown by E. carinatus and D. russellii venoms, and thus O. hannah venom was found to exert procoagulant activity through the common pathway of blood coagulation, while N. naja venom increased aPTT and TCT but not PT, and hence it was found to exert anticoagulant activity through the intrinsic pathway. Venoms of O. hannah, E. carinatus, and D. russellii lack plasminogen activation property as they do not hydrolyze azocasein, while they all show plasmin-like activity by degrading the fibrin clot. Although N. naja venom did not degrade azocasein, unlike other venoms, it showed feeble plasmin-like activity on fibrin clot. Venom of E. carinatus induced clotting of human platelet rich plasma (PRP), while the other three venoms interfered in agonist-induced platelet aggregation in PRP. Venom of O. hannah least inhibited the ADP induced platelet aggregation as compared to D. russellii and N. naja venoms. All these three venoms showed complete inhibition of epinephrine-induced aggregation at varied doses. However, O. hannah venom was unique in inhibiting thrombin induced aggregation.

  2. Sea snakes rarely venture far from home.

    Science.gov (United States)

    Lukoschek, Vimoksalehi; Shine, Richard

    2012-06-01

    The extent to which populations are connected by dispersal influences all aspects of their biology and informs the spatial scale of optimal conservation strategies. Obtaining direct estimates of dispersal is challenging, particularly in marine systems, with studies typically relying on indirect approaches to evaluate connectivity. To overcome this challenge, we combine information from an eight-year mark-recapture study with high-resolution genetic data to demonstrate extremely low dispersal and restricted gene flow at small spatial scales for a large, potentially mobile marine vertebrate, the turtleheaded sea snake (Emydocephalus annulatus). Our mark-recapture study indicated that adjacent bays in New Caledonia (snake populations. Sea snakes could easily swim between bays but rarely do so. Of 817 recaptures of marked snakes, only two snakes had moved between bays. We genotyped 136 snakes for 11 polymorphic microsatellite loci and found statistically significant genetic divergence between the two bays (F(ST)= 0.008, P snakes rarely venture far from home, which has strong implications for their ecology, evolution, and conservation.

  3. Coral snakes predict the evolution of mimicry across New World snakes.

    Science.gov (United States)

    Davis Rabosky, Alison R; Cox, Christian L; Rabosky, Daniel L; Title, Pascal O; Holmes, Iris A; Feldman, Anat; McGuire, Jimmy A

    2016-05-05

    Batesian mimicry, in which harmless species (mimics) deter predators by deceitfully imitating the warning signals of noxious species (models), generates striking cases of phenotypic convergence that are classic examples of evolution by natural selection. However, mimicry of venomous coral snakes has remained controversial because of unresolved conflict between the predictions of mimicry theory and empirical patterns in the distribution and abundance of snakes. Here we integrate distributional, phenotypic and phylogenetic data across all New World snake species to demonstrate that shifts to mimetic coloration in nonvenomous snakes are highly correlated with coral snakes in both space and time, providing overwhelming support for Batesian mimicry. We also find that bidirectional transitions between mimetic and cryptic coloration are unexpectedly frequent over both long- and short-time scales, challenging traditional views of mimicry as a stable evolutionary 'end point' and suggesting that insect and snake mimicry may have different evolutionary dynamics.

  4. Coral snakes predict the evolution of mimicry across New World snakes

    Science.gov (United States)

    Davis Rabosky, Alison R.; Cox, Christian L.; Rabosky, Daniel L.; Title, Pascal O.; Holmes, Iris A.; Feldman, Anat; McGuire, Jimmy A.

    2016-01-01

    Batesian mimicry, in which harmless species (mimics) deter predators by deceitfully imitating the warning signals of noxious species (models), generates striking cases of phenotypic convergence that are classic examples of evolution by natural selection. However, mimicry of venomous coral snakes has remained controversial because of unresolved conflict between the predictions of mimicry theory and empirical patterns in the distribution and abundance of snakes. Here we integrate distributional, phenotypic and phylogenetic data across all New World snake species to demonstrate that shifts to mimetic coloration in nonvenomous snakes are highly correlated with coral snakes in both space and time, providing overwhelming support for Batesian mimicry. We also find that bidirectional transitions between mimetic and cryptic coloration are unexpectedly frequent over both long- and short-time scales, challenging traditional views of mimicry as a stable evolutionary ‘end point' and suggesting that insect and snake mimicry may have different evolutionary dynamics. PMID:27146100

  5. Venom peptide analysis of Vipera ammodytes meridionalis (Viperinae) and Bothrops jararacussu (Crotalinae) demonstrates subfamily-specificity of the peptidome in the family Viperidae.

    Science.gov (United States)

    Munawar, Aisha; Trusch, Maria; Georgieva, Dessislava; Spencer, Patrick; Frochaux, Violette; Harder, Sönke; Arni, Raghuvir K; Duhalov, Deyan; Genov, Nicolay; Schlüter, Hartmut; Betzel, Christian

    2011-12-01

    Snake venom peptidomes are valuable sources of pharmacologically active compounds. We analyzed the peptidic fractions (peptides with molecular masses Viperidae family: BPPs are the major peptide component of the Crotalinae venom peptidome lacking Kunitz-type inhibitors (with one exception) while the Viperinae venom, in addition to BPPs, can contain peptides of the bovine pancreatic trypsin inhibitor family. We found indications for a post-translational phosphorylation of serine residues in Bothrops jararacussu venom BPP (S[combining low line]QGLPPGPPIP), which could be a regulatory mechanism in their interactions with ACE, and might influence the hypotensive effect. Homology between venom BPPs from Viperidae snakes and venom natriuretic peptide precursors from Elapidae snakes suggests a structural similarity between the respective peptides from the peptidomes of both snake families. The results demonstrate that the venoms of both snakes are rich sources of peptides influencing important physiological systems such as blood pressure regulation and hemostasis. The data can be used for pharmacological and medical applications.

  6. The Hidden Snake in the Grass: Superior Detection of Snakes in Challenging Attentional Conditions.

    Directory of Open Access Journals (Sweden)

    Sandra C Soares

    Full Text Available Snakes have provided a serious threat to primates throughout evolution. Furthermore, bites by venomous snakes still cause significant morbidity and mortality in tropical regions of the world. According to the Snake Detection Theory (SDT Isbell, 2006; 2009, the vital need to detect camouflaged snakes provided strong evolutionary pressure to develop astute perceptual capacity in animals that were potential targets for snake attacks. We performed a series of behavioral tests that assessed snake detection under conditions that may have been critical for survival. We used spiders as the control stimulus because they are also a common object of phobias and rated negatively by the general population, thus commonly lumped together with snakes as "evolutionary fear-relevant". Across four experiments (N = 205 we demonstrate an advantage in snake detection, which was particularly obvious under visual conditions known to impede detection of a wide array of common stimuli, for example brief stimulus exposures, stimuli presentation in the visual periphery, and stimuli camouflaged in a cluttered environment. Our results demonstrate a striking independence of snake detection from ecological factors that impede the detection of other stimuli, which suggests that, consistent with the SDT, they reflect a specific biological adaptation. Nonetheless, the empirical tests we report are limited to only one aspect of this rich theory, which integrates findings across a wide array of scientific disciplines.

  7. The Hidden Snake in the Grass: Superior Detection of Snakes in Challenging Attentional Conditions.

    Science.gov (United States)

    Soares, Sandra C; Lindström, Björn; Esteves, Francisco; Ohman, Arne

    2014-01-01

    Snakes have provided a serious threat to primates throughout evolution. Furthermore, bites by venomous snakes still cause significant morbidity and mortality in tropical regions of the world. According to the Snake Detection Theory (SDT Isbell, 2006; 2009), the vital need to detect camouflaged snakes provided strong evolutionary pressure to develop astute perceptual capacity in animals that were potential targets for snake attacks. We performed a series of behavioral tests that assessed snake detection under conditions that may have been critical for survival. We used spiders as the control stimulus because they are also a common object of phobias and rated negatively by the general population, thus commonly lumped together with snakes as "evolutionary fear-relevant". Across four experiments (N = 205) we demonstrate an advantage in snake detection, which was particularly obvious under visual conditions known to impede detection of a wide array of common stimuli, for example brief stimulus exposures, stimuli presentation in the visual periphery, and stimuli camouflaged in a cluttered environment. Our results demonstrate a striking independence of snake detection from ecological factors that impede the detection of other stimuli, which suggests that, consistent with the SDT, they reflect a specific biological adaptation. Nonetheless, the empirical tests we report are limited to only one aspect of this rich theory, which integrates findings across a wide array of scientific disciplines.

  8. The Hidden Snake in the Grass: Superior Detection of Snakes in Challenging Attentional Conditions

    Science.gov (United States)

    Soares, Sandra C.; Lindström, Björn; Esteves, Francisco; Öhman, Arne

    2014-01-01

    Snakes have provided a serious threat to primates throughout evolution. Furthermore, bites by venomous snakes still cause significant morbidity and mortality in tropical regions of the world. According to the Snake Detection Theory (SDT Isbell, 2006; 2009), the vital need to detect camouflaged snakes provided strong evolutionary pressure to develop astute perceptual capacity in animals that were potential targets for snake attacks. We performed a series of behavioral tests that assessed snake detection under conditions that may have been critical for survival. We used spiders as the control stimulus because they are also a common object of phobias and rated negatively by the general population, thus commonly lumped together with snakes as “evolutionary fear-relevant”. Across four experiments (N = 205) we demonstrate an advantage in snake detection, which was particularly obvious under visual conditions known to impede detection of a wide array of common stimuli, for example brief stimulus exposures, stimuli presentation in the visual periphery, and stimuli camouflaged in a cluttered environment. Our results demonstrate a striking independence of snake detection from ecological factors that impede the detection of other stimuli, which suggests that, consistent with the SDT, they reflect a specific biological adaptation. Nonetheless, the empirical tests we report are limited to only one aspect of this rich theory, which integrates findings across a wide array of scientific disciplines. PMID:25493937

  9. Sea Snake Harvest in the Gulf of Thailand

    DEFF Research Database (Denmark)

    Van Cao, Nguyen; Thien Tao, Nguyen; Moore, Amelia

    2014-01-01

    Abstract: Conservation of sea snakes is virtually nonexistent in Asia, and its role in human–snake interactions in terms of catch, trade, and snakebites as an occupational hazard is mostly unexplored. We collected data on sea snake landings from the Gulf of Thailand, a hotspot for sea snake harvest...... sell snakes to merchants who sort, package, and ship the snakes to various destinations in Vietnam and China for human consumption and as a source of traditional remedies. Annually, 82 t, roughly equal to 225,500 individuals, of live sea snakes are brought to ports. To our knowledge, this rate...... of harvest constitutes one of the largest venomous snake and marine reptile harvest activities in the world today. Lapemis curtus and Hydrophis cyanocinctus constituted about 85% of the snake biomass, and Acalyptophis peronii, Aipysurus eydouxii, Hydrophis atriceps, H. belcheri, H. lamberti, and H. ornatus...

  10. Safe Handling of Snakes in an ED Setting.

    Science.gov (United States)

    Cockrell, Melanie; Swanson, Kristofer; Sanders, April; Prater, Samuel; von Wenckstern, Toni; Mick, JoAnn

    2017-01-01

    Efforts to improve consistency in management of snakes and venomous snake bites in the emergency department (ED) can improve patient and staff safety and outcomes, as well as improve surveillance data accuracy. The emergency department at a large academic medical center identified an opportunity to implement a standardized process for snake disposal and identification to reduce staff risk exposure to snake venom from snakes patients brought with them to the ED. A local snake consultation vendor and zoo Herpetologist assisted with development of a process for snake identification and disposal. All snakes have been identified and securely disposed of using the newly implemented process and no safety incidents have been reported. Other emergency department settings may consider developing a standardized process for snake disposal using listed specialized consultants combined with local resources and suppliers to promote employee and patient safety. Copyright © 2017 Emergency Nurses Association. Published by Elsevier Inc. All rights reserved.

  11. 2015 OLC FEMA Lidar: Snake River, ID

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Quantum Spatial has collected Light Detection and Ranging (LiDAR) data for the Oregon LiDAR Consortium (OLC) Snake River FEMA study area. This study area is located...

  12. Spin flipping in rings with Siberian Snakes

    Energy Technology Data Exchange (ETDEWEB)

    Mane, S.R. [Convergent Computing Inc., P.O. Box 561, Shoreham, NY 11786 (United States)], E-mail: srmane@optonline.net

    2009-07-01

    I display numerical spin tracking simulations for spin flippers in model storage rings with full or nearly full Siberian Snakes. In many cases, the results differ from the predictions using the Froissart-Stora formula.

  13. Friction enhancement in concertina locomotion of snakes

    Science.gov (United States)

    Marvi, Hamidreza; Hu, David L.

    2012-01-01

    Narrow crevices are challenging terrain for most organisms and biomimetic robots. Snakes move through crevices using sequential folding and unfolding of their bodies in the manner of an accordion or concertina. In this combined experimental and theoretical investigation, we elucidate this effective means of moving through channels. We measure the frictional properties of corn snakes, their body kinematics and the transverse forces they apply to channels of varying width and inclination. To climb channels inclined at 60°, we find snakes use a combination of ingenious friction-enhancing techniques, including digging their ventral scales to double their frictional coefficient and pushing channel walls transversely with up to nine times body weight. Theoretical modelling of a one-dimensional n-linked crawler is used to calculate the transverse force factor of safety: we find snakes push up to four times more than required to prevent sliding backwards, presumably trading metabolic energy for an assurance of wall stability. PMID:22728386

  14. Experimental Infection of Snakes with Ophidiomyces ophiodiicola Causes Pathological Changes That Typify Snake Fungal Disease.

    Science.gov (United States)

    Lorch, Jeffrey M; Lankton, Julia; Werner, Katrien; Falendysz, Elizabeth A; McCurley, Kevin; Blehert, David S

    2015-11-17

    Snake fungal disease (SFD) is an emerging skin infection of wild snakes in eastern North America. The fungus Ophidiomyces ophiodiicola is frequently associated with the skin lesions that are characteristic of SFD, but a causal relationship between the fungus and the disease has not been established. We experimentally infected captive-bred corn snakes (Pantherophis guttatus) in the laboratory with pure cultures of O. ophiodiicola. All snakes in the infected group (n = 8) developed gross and microscopic lesions identical to those observed in wild snakes with SFD; snakes in the control group (n = 7) did not develop skin infections. Furthermore, the same strain of O. ophiodiicola used to inoculate snakes was recovered from lesions of all animals in the infected group, but no fungi were isolated from individuals in the control group. Monitoring progression of lesions throughout the experiment captured a range of presentations of SFD that have been described in wild snakes. The host response to the infection included marked recruitment of granulocytes to sites of fungal invasion, increased frequency of molting, and abnormal behaviors, such as anorexia and resting in conspicuous areas of enclosures. While these responses may help snakes to fight infection, they could also impact host fitness and may contribute to mortality in wild snakes with chronic O. ophiodiicola infection. This work provides a basis for understanding the pathogenicity of O. ophiodiicola and the ecology of SFD by using a model system that incorporates a host species that is easy to procure and maintain in the laboratory. Skin infections in snakes, referred to as snake fungal disease (SFD), have been reported with increasing frequency in wild snakes in the eastern United States. While most of these infections are associated with the fungus Ophidiomyces ophiodiicola, there has been no conclusive evidence to implicate this fungus as a primary pathogen. Furthermore, it is not understood why the

  15. Nest defense- Grassland bird responses to snakes

    Science.gov (United States)

    Ellison, Kevin S.; Ribic, Christine

    2012-01-01

    Predation is the primary source of nest mortality for most passerines; thus, behaviors to reduce the impacts of predation are frequently quantified to study learning, adaptation, and coevolution among predator and prey species. Video surveillance of nests has made it possible to examine real-time parental nest defense. During 1999-2009, we used video camera systems to monitor 518 nests of grassland birds. We reviewed video of 48 visits by snakes to 34 nests; 37 of these visits resulted in predation of active nests. When adult birds encountered snakes at the nest (n = 33 visits), 76% of the encounters resulted in a form of nest defense (nonaggressive or aggressive); in 47% of the encounters, birds physically struck snakes. When defending nests, most birds pecked at the snakes; Eastern Meadowlarks (Sturnella magna) and Bobolinks (Dolichonyx oryzivorus) pecked most frequently in anyone encounter. Also, two Eastern Meadowlarks ran around snakes, frequently with wings spread, and three Bobolinks struck at snakes from the air. Nest defense rarely appeared to alter snake behavior; the contents of seven nests defended aggressively and two nests defended nonaggressively were partially depredated, whereas the contents of six nests defended each way were consumed completely. One fledgling was produced at each of three nests that had been aggressively defended. During aggressive defense, one snake appeared to be driven away and one was wounded. Our findings should be a useful starting point for further research. For example, future researchers may be able to determine whether the behavioral variation we observed in nest defense reflects species differences, anatomic or phylogenetic constraints, or individual differences related to a bird's prior experience. There appears to be much potential for studying nest defense behavior using video recording of both real and simulated encounters. 

  16. Prey handling and diet of Louisiana pine snakes (Pituophis ruthveni) and black pine snakes (P. melanoleucus lodingi), with comparisons to other selected colubrid snakes

    Science.gov (United States)

    D. Craig Rudolph; Shirley J. Burgdorf; Richard N. Conner; Christopher S. Collins; Daniel Saenz; Richard R. Schaefer; Toni Trees; C. Michael Duran; Marc Ealy; John G. Himes

    2002-01-01

    Diet and prey handling behavior were determined for Louisiana pine snakes (Pituophis ruthveni) and black pine snakes (P. melanoleucus lodingi). Louisiana pine snakes prey heavily on Baird's pocket gophers (Geomys breviceps), with which they are sympatric, and exhibit specialized behaviors that facilitate...

  17. Phylogeny, ecology, and heart position in snakes

    DEFF Research Database (Denmark)

    Gartner, Gabriel E.A.; Hicks, James W.; Manzani, Paulo R.

    2010-01-01

    The cardiovascular system of all animals is affected by gravitational pressure gradients, the intensity of which varies according to organismic features, behavior, and habitat occupied. A previous nonphylogenetic analysis of heart position in snakes-which often assume vertical postures-found the ......The cardiovascular system of all animals is affected by gravitational pressure gradients, the intensity of which varies according to organismic features, behavior, and habitat occupied. A previous nonphylogenetic analysis of heart position in snakes-which often assume vertical postures......, whereas an anterior heart position would not be needed in aquatic habitats, where the effects of gravity are less pronounced. We analyzed a new data set of 155 species from five major families of Alethinophidia (one of the two major branches of snakes, the other being blind snakes, Scolecophidia) using...... counterparts. The best‐fit model predicting snake heart position included aspects of both habitat and clade and indicated that arboreal snakes in our study tend to have hearts placed more posteriorly, opposite the trend identified in previous studies. Phylogenetic signal in relative heart position was apparent...

  18. Negative snakes in JET: evidence for negative shear

    Energy Technology Data Exchange (ETDEWEB)

    Gill, R.D.; Alper, B.; Edwards, A.W. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Pearson, D. [Reading Univ. (United Kingdom)

    1994-07-01

    The signature of the negative snakes from the soft X-ray cameras is very similar to the more usual snakes except that the localised region of the snake has, compared with its surroundings, decreased rather than increased emission. Circumstances where negative snakes have been seen are reviewed. The negative snake appears as a region of increased resistance and of increased impurity density. The relationship between the shear and the current perturbation is shown, and it seem probable that the magnetic shear is reversed at the point of the negative snake, i.e. that q is decreasing with radius. 6 refs., 6 figs.

  19. Anti-snake venom: use and adverse reaction in a snake bite study clinic in Bangladesh

    Directory of Open Access Journals (Sweden)

    MR Amin

    2008-01-01

    Full Text Available Snakebites can present local or systemic envenomation, while neurotoxicity and respiratory paralysis are the main cause of death. The mainstay of management is anti-snake venom (ASV, which is highly effective, but liable to cause severe adverse reactions including anaphylaxis. The types of adverse reaction to polyvalent anti-snake venom have not been previously studied in Bangladesh. In this prospective observational study carried out between 1999 and 2001, in the Snake Bite Study Clinic of Chittagong Medical College Hospital, 35 neurotoxic-snake-bite patients who had received polyvalent anti-snake venom were included while the ones sensitized to different antitoxins and suffering from atopy were excluded. The common neurotoxic features were ptosis (100%, external ophthalmoplegia (94.2%, dysphagia (77.1%, dysphonia (68.5% and broken neck sign (80%. The percentage of anti-snake venom reaction cases was 88.57%; pyrogenic reaction was 80.64%; and anaphylaxis was 64.51%. The common features of anaphylaxis were urticaria (80%; vomiting and wheezing (40%; and angioedema (10%. The anti-snake venom reaction was treated mainly with adrenaline for anaphylaxis and paracetamol suppository in pyrogenic reactions. The average recovery time was 4.5 hours. Due to the danger of reactions the anti-snake venom should not be withheld from a snakebite victim when indicated and appropriate guidelines should be followed for its administration.

  20. Experimental infection of snakes with Ophidiomyces ophiodiicola causes pathological changes that typify snake fungal disease

    Science.gov (United States)

    Lorch, Jeffrey M.; Lankton, Julia S.; Werner, Katrien; Falendysz, Elizabeth A.; McCurley, Kevin; Blehert, David S.

    2015-01-01

    Snake fungal disease (SFD) is an emerging skin infection of wild snakes in eastern North America. The fungus Ophidiomyces ophiodiicola is frequently associated with the skin lesions that are characteristic of SFD, but a causal relationship between the fungus and the disease has not been established. We experimentally infected captive-bred corn snakes (Pantherophis guttatus) in the laboratory with pure cultures of O. ophiodiicola. All snakes in the infected group (n = 8) developed gross and microscopic lesions identical to those observed in wild snakes with SFD; snakes in the control group (n = 7) did not develop skin infections. Furthermore, the same strain of O. ophiodiicola used to inoculate snakes was recovered from lesions of all animals in the infected group, but no fungi were isolated from individuals in the control group. Monitoring progression of lesions throughout the experiment captured a range of presentations of SFD that have been described in wild snakes. The host response to the infection included marked recruitment of granulocytes to sites of fungal invasion, increased frequency of molting, and abnormal behaviors, such as anorexia and resting in conspicuous areas of enclosures. While these responses may help snakes to fight infection, they could also impact host fitness and may contribute to mortality in wild snakes with chronic O. ophiodiicola infection. This work provides a basis for understanding the pathogenicity of O. ophiodiicola and the ecology of SFD by using a model system that incorporates a host species that is easy to procure and maintain in the laboratory.

  1. Cardiovascular Responses of Snakes to Gravitational Gradients

    Science.gov (United States)

    Hsieh, Shi-Tong T.; Lillywhite, H. B.; Ballard, R. E.; Hargens, A. R.; Holton, Emily M. (Technical Monitor)

    1998-01-01

    Snakes are useful vertebrates for studies of gravitational adaptation, owing to their elongate body and behavioral diversification. Scansorial species have evolved specializations for regulating hemodynamics during exposure to gravitational stress, whereas, such adaptations are less well developed in aquatic and non-climbing species. We examined responses of the amphibious snake,\\italicize (Nerodia rhombifera), to increments of Gz (head-to-tail) acceleration force on both a short- and long-arm centrifuge (1.5 vs. 3.7 m radius, from the hub to tail end of snake). We recorded heart rate, dorsal aortic pressure, and carotid arterial blood flow during stepwise 0.25 G increments of Gz force (referenced at the tail) in conscious animals. The Benz tolerance of a snake was determined as the Gz level at which carotid blood flow ceased and was found to be significantly greater at the short- than long-arm centrifuge radius (1.57 Gz vs. 2.0 Gz, respectively; P=0.016). A similar pattern of response was demonstrated in semi-arboreal rat snakes,\\italicize{Elaphe obsoleta}, which are generally more tolerant of Gz force (2.6 Gz at 1.5m radius) than are water snakes. The tolerance differences of the two species reflected cardiovascular responses, which differed quantitatively but not qualitatively: heart rates increased while arterial pressure and blood flow decreased in response to increasing levels of Gz. Thus, in both species of snakes, a reduced gradient of Gz force (associated with greater centrifuge radius) significantly decreases the Gz level that can be tolerated.

  2. Snake instability of dark solitons in fermionic superfluids

    OpenAIRE

    Cetoli, A.; Brand, J.; Scott, R. G.; Dalfovo, F.; Pitaevskii, L. P.

    2013-01-01

    We present numerical calculations of the snake instability in a Fermi superfluid within the Bogoliubov-de Gennes theory of the BEC to BCS crossover using the random phase approximation complemented by time-dependent simulations. We examine the snaking behaviour across the crossover and quantify the timescale and lengthscale of the instability. While the dynamic shows extensive snaking before eventually producing vortices and sound on the BEC side of the crossover, the snaking dynamics is pree...

  3. Ugrizi strupenih kač: Bites by venomous snakes:

    OpenAIRE

    Grenc, Damjan

    2009-01-01

    Eight different species of non-venomous snakes of the Colubridae family, and three different species of poisonous snakes of the Viperidae family are native in Slovenia. In the period between 1999 and October of 2008, 39 snake bites were reported to the Poison Control Centre. The most common clinical findings in snake bite victims are discernible fang marks, rapidly progressive swelling, pain, ecchymosis, lymphangitis, and regional lymphadenitis. Systemic signs of envenomation can be delayed a...

  4. Neurological manifestations of snake bite in Sri Lanka.

    OpenAIRE

    Seneviratne U; Dissanayake S

    2002-01-01

    BACKGROUND AND AIMS: Snake bite is an important cause of mortality and morbidity in certain parts of Sri Lanka. This study was designed to determine the offending snakes, neurological manifestations, disease course, and outcome in neurotoxic envenomation. METHODS AND MATERIAL: Fifty six consecutive patients admitted with neurological manifestations following snake bite were studied prospectively. Data were obtained regarding the offending snakes, neurological symptoms, time taken for onset of...

  5. Oral microbiota of Brazilian captive snakes

    Directory of Open Access Journals (Sweden)

    MG Fonseca

    2009-01-01

    Full Text Available The present work aimed to determine the oral microbiotic composition of snakes from São José do Rio Preto city, São Paulo State, Brazil. Ten snake species, comprising the families Boidae, Colubridae, Elapidae and Viperidae, were submitted to microbiological examination of their oral cavity, which indicated positivity for all buccal samples. Gram-negative bacilli, gram-negative cocci bacilli, gram-positive bacilli and gram-positive cocci were isolated from the snakes. Among isolated bacterium species, the occurrence of coagulase-negative staphylococci in the buccal cavity of Crotalus durissus (Viperiade, Eunectes murinus (Boidae, Mastigodryas bifossatus (Colubridae and Bacillus subtilis, common to oral cavity of Bothrops alternatus (Viperidae and Phalotris mertensi (Colubridae, was detected. It was observed higher diversity of isolated bacteria from the oral cavity of Micrurus frontalis (Elapidae and Philodryas nattereri (Colubridae, as well as the prevalence of gram-positive baccillus and gram-positive cocci. The composition of the oral microbiota of the studied snakes, with or without inoculating fangs, is diverse and also related to the formation of abscesses at the bite site in the victims of the ophidian accidents, and to pathogenic processes in the snakes that host these microorganisms.

  6. Pelagic sea snakes dehydrate at sea.

    Science.gov (United States)

    Lillywhite, Harvey B; Sheehy, Coleman M; Brischoux, François; Grech, Alana

    2014-05-07

    Secondarily marine vertebrates are thought to live independently of fresh water. Here, we demonstrate a paradigm shift for the widely distributed pelagic sea snake, Hydrophis (Pelamis) platurus, which dehydrates at sea and spends a significant part of its life in a dehydrated state corresponding to seasonal drought. Snakes that are captured following prolonged periods without rainfall have lower body water content, lower body condition and increased tendencies to drink fresh water than do snakes that are captured following seasonal periods of high rainfall. These animals do not drink seawater and must rehydrate by drinking from a freshwater lens that forms on the ocean surface during heavy precipitation. The new data based on field studies indicate unequivocally that this marine vertebrate dehydrates at sea where individuals may live in a dehydrated state for possibly six to seven months at a time. This information provides new insights for understanding water requirements of sea snakes, reasons for recent declines and extinctions of sea snakes and more accurate prediction for how changing patterns of precipitation might affect these and other secondarily marine vertebrates living in tropical oceans.

  7. Function of snake mobbing in spectral tarsiers.

    Science.gov (United States)

    Gursky, Sharon

    2006-04-01

    Numerous species are known for their tendency to approach and confront their predators as a group. This behavior is known as mobbing. Snakes seem to be one of the more consistent recipients of this type of predator-directed behavior. This paper explores individual differences (sex and age) in the mobbing behavior of the spectral tarsier toward live and model snakes. This study was conducted at Tangkoko Nature Reserve (Sulawesi, Indonesia) during 2003-2004. During this research, 11 natural mobbing events and 31 artificially induced mobbing events were observed. The mean number of individuals at a mobbing was 5.7. The duration of mobbing events was strongly correlated with the number of assembled mobbers. Adults were more likely than other age classes to participate in mobbings. Males were more likely than females to participate in mobbings. Mobbing groups often contained more than one adult male, despite the fact that no spectral tarsier group contains more than one adult male. No difference in body size between extragroup males and resident males was observed, refuting the "attract the mightier" hypothesis. The number of mobbers did not affect whether the tarsier or the snake retreated first, countering the "move-on" hypothesis. The "perception advertisement" hypothesis was tentatively supported, in that live snakes were rarely seen in the area following mobbing calls, in comparison to when tarsiers either ignored the snake or alarm call. Copyright 2006 Wiley-Liss, Inc.

  8. Severe Coagulopathy after Ingestion of "Snake Wine".

    Science.gov (United States)

    Moon, Jeong Mi; Chun, Byeong Jo

    2016-06-01

    This report describes a patient who developed coagulopathy after ingesting snake wine, which is an alcoholic libation containing an entire venomous snake. A 68-year-old man was admitted to the hospital 19 h after ingesting snake wine. The laboratory features upon admission included unmeasurable activated partial thromboplastin (aPTT) values, prolonged prothrombin time (PT) values, increased fibrinogen levels, modestly elevated fibrin degradation product and D-dimer values, uncorrected aPTT and PT values after a mixing test, and normal levels of aspartate transaminase and alanine transaminase. No pesticides, warfarin, or superwarfarin in the patient's blood or urine were detected. His coagulation profile normalized on the 6(th) day after admission after antivenom treatment. He was discharged 10 days later without sequelae. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: The physician should be aware that ingesting snake wine may lead to systemic envenomation. As for coagulopathy, which may develop by ingesting snake venom, related laboratory findings may differ from the features observed after direct envenomation by snakebite. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Blood flow dynamics in the snake spectacle.

    Science.gov (United States)

    van Doorn, Kevin; Sivak, Jacob G

    2013-11-15

    The eyes of snakes are shielded beneath a layer of transparent integument referred to as the 'reptilian spectacle'. Well adapted to vision by virtue of its optical transparency, it nevertheless retains one characteristic of the integument that would otherwise prove detrimental to vision: its vascularity. Given the potential consequence of spectacle blood vessels on visual clarity, one might expect adaptations to have evolved that mitigate their negative impact. Earlier research demonstrated an adaptation to their spatial layout in only one species to reduce the vessels' density in the region serving the foveal and binocular visual fields. Here, we present a study of spectacle blood flow dynamics and provide evidence of a mechanism to mitigate the spectacle blood vessels' deleterious effect on vision by regulation of blood flow through them. It was found that when snakes are at rest and undisturbed, spectacle vessels undergo cycles of dilation and constriction, such that the majority of the time the vessels are fully constricted, effectively removing them from the visual field. When snakes are presented with a visual threat, spectacle vessels constrict and remain constricted for longer periods than occur during the resting cycles, thus guaranteeing the best possible visual capabilities in times of need. Finally, during the snakes' renewal phase when they are generating a new stratum corneum, the resting cycle is abolished, spectacle vessels remain dilated and blood flow remains strong and continuous. The significance of these findings in terms of the visual capabilities and physiology of snakes is discussed.

  10. Molecular detection of Toxoplasma gondii in snakes.

    Science.gov (United States)

    Nasiri, Vahid; Teymurzadeh, Shohreh; Karimi, Gholamreza; Nasiri, Mehdi

    2016-10-01

    Toxoplasma gondii, an obligate intracellular protozoan parasite, is responsible for one of the most common zoonotic parasitic diseases in almost all warm-blooded vertebrates worldwide, and it is estimated that about one-third of the world human population is chronically infected with this parasite. Little is known about the circulation of T. gondii in snakes and this study for the first time aimed to evaluate the infection rates of snakes by this parasite by PCR methods. The brain of 68 Snakes, that were collected between May 2012 and September 2015 and died after the hold in captivity, under which they were kept for taking poisons, were examined for the presence of this parasite. DNA was extracted and Nested-PCR method was carried out with two of pairs of primers to detect the 344 bp fragment of T. gondii GRA6 gene. Five positive nested-PCR products were directly sequenced in the forward and reverse directions by Sequetech Company (Mountain View, CA). T. gondii GRA6 gene were detected from 55 (80.88%) of 68 snakes brains. Sequencing of the GRA6 gene revealed 98-100% of similarity with T. gondii sequences deposited in GenBank. To our knowledge, this is the first study of molecular detection of T. gondii in snakes and our findings show a higher frequency of this organism among them. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Pelagic sea snakes dehydrate at sea

    Science.gov (United States)

    Lillywhite, Harvey B.; Sheehy, Coleman M.; Brischoux, François; Grech, Alana

    2014-01-01

    Secondarily marine vertebrates are thought to live independently of fresh water. Here, we demonstrate a paradigm shift for the widely distributed pelagic sea snake, Hydrophis (Pelamis) platurus, which dehydrates at sea and spends a significant part of its life in a dehydrated state corresponding to seasonal drought. Snakes that are captured following prolonged periods without rainfall have lower body water content, lower body condition and increased tendencies to drink fresh water than do snakes that are captured following seasonal periods of high rainfall. These animals do not drink seawater and must rehydrate by drinking from a freshwater lens that forms on the ocean surface during heavy precipitation. The new data based on field studies indicate unequivocally that this marine vertebrate dehydrates at sea where individuals may live in a dehydrated state for possibly six to seven months at a time. This information provides new insights for understanding water requirements of sea snakes, reasons for recent declines and extinctions of sea snakes and more accurate prediction for how changing patterns of precipitation might affect these and other secondarily marine vertebrates living in tropical oceans. PMID:24648228

  12. Curvilinear shapes and the snake detection hypothesis : An ERP study

    NARCIS (Netherlands)

    Van Strien, Jan W; Christiaans, Gerwin; Franken, Ingmar H A; Huijding, Jorg

    Consistent with the snake detection hypothesis, previous ERP studies have established a larger early posterior negativity (EPN) in response to pictures depicting snakes than to pictures depicting other creatures. Here, we examined to what extent the curvilinear shape of the snake's body drives the

  13. Venomous Snake Bite Injuries at Kitui District Hospital

    African Journals Online (AJOL)

    presentation patterns and treatments offered for snake bites at Kitui District Hospital, and to characterize the causative venomous snakes. Patients and methods. This was a prospective case series carried out over a period of 8 months. Patients presenting at the hospital with snake bites were included in the study. A pre set.

  14. A successful trap design for capturing large terrestrial snakes

    Science.gov (United States)

    Shirley J. Burgdorf; D. Craig Rudolph; Richard N. Conner; Daniel Saenz; Richard R. Schaefer

    2005-01-01

    Large scale trapping protocols for snakes can be expensive and require large investments of personnel and time. Typical methods, such as pitfall and small funnel traps, are not useful or suitable for capturing large snakes. A method was needed to survey multiple blocks of habitat for the Louisiana Pine Snake (Pituophis ruthveni), throughout its...

  15. Snake and staff symbolism in healing | Retief | Acta Theologica

    African Journals Online (AJOL)

    Since time immemorial the snake has been venerated as an enigmatic creature with supernatural powers. As a snake and staff symbol it is also traditionally associated with the healing arts, either as the single-snake attribute of Asclepius, or as the doublesnake attribute of Hermes. In this article the mythological basis for this ...

  16. Snakes in the Grass: Weaving Success for Everyone.

    Science.gov (United States)

    Ide, Janet L.

    2000-01-01

    Describes "Snakes in the Grass," a weaving project used with special needs students. Discusses the preliminary skill-building activities used, the process for creating the students' individual snakes, and the preparation and process for how the students wove the snakes. (CMK)

  17. Cross neutralization of coral snake venoms by commercial Australian snake antivenoms.

    Science.gov (United States)

    Ramos, Henrique Roman; Vassão, Ruth Camargo; de Roodt, Adolfo Rafael; Santos E Silva, Ed Carlos; Mirtschin, Peter; Ho, Paulo Lee; Spencer, Patrick Jack

    2017-01-01

    Although rare, coral snake envenomation is a serious health threat in Brazil, because of the highly neurotoxic venom and the scarcely available antivenom. The major bottleneck for antivenom production is the low availability of venom. Furthermore, the available serum is not effective against all coral snake species found in Brazil. An alternative to circumvent the lack of venom for serum production and the restricted protection of the actually available antivenom would be of great value. We compared the Brazilian coral snake and mono and polyvalent Australian antivenoms in terms of reactivity and protection. The immunoreactivity of venoms from 9 coral snakes species were assayed by ELISA and western blot using the Brazilian Micrurus and the Australian pentavalent as well as monovalent anti-Notechis, Oxyuranus and Pseudechis antivenoms. Neutralization assays were performed in mice, using 3 LD 50 of the venoms, incubated for 30 minutes with 100 μL of antivenom/animal. All the venoms reacted against the autologous and heterologous antivenoms. Nevertheless, the neutralization assays showed that the coral snake antivenom was only effective against M. corallinus, M. frontalis, M. fulvius, M. nigrocinctus and M. pyrrhocryptus venoms. On the other hand, the Australian pentavalent antivenom neutralized all venoms except the one from M. spixii. A combination of anti-Oxyuranus and Pseudechis monovalent sera, extended the protection to M. altirostris and, partially, to M. ibiboboca. By adding Notechis antivenom to this mixture, we obtained full protection against M. ibiboboca and partial neutralization against M. lemniscatus venoms. Our findings confirm the limited effectiveness of the Brazilian coral snake antivenom and indicate that antivenoms made from Australian snakes venoms are an effective alternative for coral snake bites in South America and also in the United States were coral snake antivenom production has been discontinued.

  18. Snake Envenomation Causing Distant Tracheal Myonecrosis

    Directory of Open Access Journals (Sweden)

    Amina Khimani

    2013-01-01

    Full Text Available Snakebites are often believed to be poisonous. However, this is not always the case. In fact, each bite differs from snake to snake, depending on if the snake is poisonous and if there is envenomation. Venom in pit viper snakebites is often associated with local necrosis. The abundant literature selections and research articles justify local myonecrosis due to envenomation, but there is not much in the literature regarding myonecrosis at a site distant from the snakebite. We hereby present a case of a 42-year-old man who was transferred to our emergency department after a rattlesnake bit him twice. The patient, besides developing local myonecrosis at the site of the snakebite, developed necrosis of the scrotum as well as tracheal pressure myonecrosis at the site of the endotracheal tube balloon. In this review, we will attempt to discuss the myonecrosis pathophysiology and management related to the rattle snakebite.

  19. Drinking in snakes: resolving a biomechanical puzzle.

    Science.gov (United States)

    Cundall, David; Brainerd, Elizabeth L; Constantino, Joseph; Deufel, Alexandra; Grapski, Douglas; Kley, Nathan J

    2012-03-01

    Snakes have long been thought to drink with a two-phase buccal-pump mechanism, but observations that some snakes can drink without sealing the margins of their mouths suggest that buccal pumping may not be the only drinking mechanism used by snakes. Here, we report that some snakes appear to drink using sponge-like qualities of specific regions of the oropharyngeal and esophageal mucosa and sponge-compressing functions of certain muscles and bones of the head. The resulting mechanism allows them to transport water upward against the effects of gravity using movements much slower than those of many other vertebrates. To arrive at this model, drinking was examined in three snake species using synchronized ciné and electromyographic recordings of muscle activity and in a fourth species using synchronized video and pressure recordings. Functional data were correlated with a variety of anatomical features to test specific predictions of the buccal-pump model. The anatomical data suggest explanations for the lack of conformity between a buccal-pump model of drinking and the performance of the drinking apparatus in many species. Electromyographic data show that many muscles with major functions in feeding play minor roles in drinking and, conversely, some muscles with minor roles in feeding play major roles in drinking. Mouth sealing by either the tongue or mental scale, previously considered critical to drinking in snakes, is incidental to drinking performance in some species. The sponge mechanism of drinking may represent a macrostomatan exaptation of mucosal folds, the evolution of which was driven primarily by the demands of feeding. © 2012 WILEY PERIODICALS, INC.

  20. Snakes of Zaire and Their Bites

    OpenAIRE

    CHIFUNDERA, Kusamba

    1990-01-01

    The ophidiological survey made in Zaire revealed the presence of 152 species of snakes included in 60 genera and in 8 families. The family Colubridae contains the largest number of genera (45) and species (97). Their geographical distribution shows that the eastern part of Kivu region contains a wild variety of species (90 species). The density of Zairean snakes has not yet been known. But in some localities like Kamanyola in the Kivu province, the density is as high as 80 individuals per squ...

  1. The status of taxonomy and venom in sea snakes

    DEFF Research Database (Denmark)

    Redsted Rasmussen, Arne; Sanders, Kate L.

    2017-01-01

    The status of taxonomy and venom in sea snakesArne R Rasmussen1, Kate L Sanders21 The Royal Danish Academy of Fine Arts, School of Architecture, Design & Conservation, Copenhagen, Denmark2 School of Earth and Environmental Sciences, University of Adelaide, Adelaide, South Australia 5000, Australia......Sea snakes form two aquatic groups of snakes with a flat vertically paddle-form tail (sea kraits and viviparous sea snakes). Sea snakes belong to the same family Elapidae, which also includes the terrestrial mambas, cobra, kraits, taipan and brown snake. All elapids are characterized by the anterior position...... of the poison-fangs on the maxillary bone (proteroglyphous). Globally there are some 70 species of sea snake found in the tropical and subtropical waters of the Indian Ocean and the Pacific Ocean. Most species are found in the Indo-Malayan Archipelago, the China Sea, Indonesia, and the Australian region...

  2. Sea snake harvest in the gulf of Thailand.

    Science.gov (United States)

    Van Cao, Nguyen; Thien Tao, Nguyen; Moore, Amelia; Montoya, Alfred; Redsted Rasmussen, Arne; Broad, Kenneth; Voris, Harold K; Takacs, Zoltan

    2014-12-01

    Conservation of sea snakes is virtually nonexistent in Asia, and its role in human-snake interactions in terms of catch, trade, and snakebites as an occupational hazard is mostly unexplored. We collected data on sea snake landings from the Gulf of Thailand, a hotspot for sea snake harvest by squid fishers operating out of the ports of Song Doc and Khanh Hoi, Ca Mau Province, Vietnam. The data were collected during documentation of the steps of the trading process and through interviewers with participants in the trade. Squid vessels return to ports once per lunar synodic cycle and fishers sell snakes to merchants who sort, package, and ship the snakes to various destinations in Vietnam and China for human consumption and as a source of traditional remedies. Annually, 82 t, roughly equal to 225,500 individuals, of live sea snakes are brought to ports. To our knowledge, this rate of harvest constitutes one of the largest venomous snake and marine reptile harvest activities in the world today. Lapemis curtus and Hydrophis cyanocinctus constituted about 85% of the snake biomass, and Acalyptophis peronii, Aipysurus eydouxii, Hydrophis atriceps, H. belcheri, H. lamberti, and H. ornatus made up the remainder. Our results establish a quantitative baseline for characteristics of catch, trade, and uses of sea snakes. Other key observations include the timing of the trade to the lunar cycle, a decline of sea snakes harvested over the study period (approximately 30% decline in mass over 4 years), and the treatment of sea snake bites with rhinoceros horn. Emerging markets in Southeast Asia drive the harvest of venomous sea snakes in the Gulf of Thailand and sea snake bites present a potentially lethal occupational hazard. We call for implementation of monitoring programs to further address the conservation implications of this large-scale marine reptile exploitation. © 2014 Society for Conservation Biology.

  3. Born Knowing: Tentacled Snakes Innately Predict Future Prey Behavior

    Science.gov (United States)

    Catania, Kenneth C.

    2010-01-01

    Background Aquatic tentacled snakes (Erpeton tentaculatus) can take advantage of their prey's escape response by startling fish with their body before striking. The feint usually startles fish toward the snake's approaching jaws. But when fish are oriented at a right angle to the jaws, the C-start escape response translates fish parallel to the snake's head. To exploit this latter response, snakes must predict the future location of the fish. Adult snakes can make this prediction. Is it learned, or are tentacled snakes born able to predict future fish behavior? Methods and Findings Laboratory-born, naïve snakes were investigated as they struck at fish. Trials were recorded at 250 or 500 frames per second. To prevent learning, snakes were placed in a water container with a clear transparency sheet or glass bottom. The chamber was placed over a channel in a separate aquarium with fish below. Thus snakes could see and strike at fish, without contact. The snake's body feint elicited C-starts in the fish below the transparency sheet, allowing strike accuracy to be quantified in relationship to the C-starts. When fish were oriented at a right angle to the jaws, naïve snakes biased their strikes to the future location of the escaping fish's head, such that the snake's jaws and the fish's translating head usually converged. Several different types of predictive strikes were observed. Conclusions The results show that some predators have adapted their nervous systems to directly compensate for the future behavior of prey in a sensory realm that usually requires learning. Instead of behavior selected during their lifetime, newborn tentacled snakes exhibit behavior that has been selected on a different scale—over many generations. Counter adaptations in fish are not expected, as tentacled snakes are rare predators exploiting fish responses that are usually adaptive. PMID:20585384

  4. The upper cretaceous snake Dinilysia patagonica Smith-Woodward, 1901, and the crista circumfenestralis of snakes.

    Science.gov (United States)

    Palci, Alessandro; Caldwell, Michael W

    2014-10-01

    Studies on the phylogenetic relationships of snakes and lizards are plagued by problematic characterizations of anatomy that are then used to define characters and states in taxon-character matrices. State assignments and character descriptions must be clear characterizations of observable anatomy and topological relationships if homologies are to be hypothesized. A supposed homology among snakes, not observed in lizards, is the presence of a crista circumfenestralis (CCF), a system of bony crests surrounding the fenestra ovalis and lateral aperture of the recessus scalae tympani. We note that there are some fossil and extant snakes that lack a CCF, and some extant lizards that possess a morphological equivalent. The phylogenetically important upper Cretaceous fossil snake Dinilysia patagonica has been interpreted by different authors as either having or lacking a CCF. These conflicting results for Dinilysia were tested by re-examining the morphology of the otic region in a large sample of snakes and lizards. An unambiguous criterion arising from the test of topology is used to define the presence of a CCF: the enclosure of the ventral margin of the juxtastapedial recess by flanges of the otoccipital (crista tuberalis and crista interfenestralis) that extend forward to contact the posterior margin of the prootic. According to this criterion D. patagonica does not possess a CCF, therefore, this anatomical feature must have arisen later during the evolution of snakes. Copyright © 2014 Wiley Periodicals, Inc.

  5. Cytotoxicity of Southeast Asian snake venoms

    Directory of Open Access Journals (Sweden)

    A Jamunaa

    2012-01-01

    Full Text Available Cytotoxicity of venoms from eleven medically important snakes found in Southeast Asia (Naja kaouthia, Naja siamensis, Naja sumatrana, Ophiophagus hannah, Bungarus candidus, Bungarus fasciatus, Enhydrina schistosa, Calloselasma rhodostoma, Trimeresurus purpureomaculatus and Tropidolaemus sumatranus was determined, based on the MTS cytotoxicity assay, which determines the survival of viable cells in monolayer MDCK and Vero cell cultures upon exposure to the snake venoms. Snake venom toxicity was expressed as the venom dose that killed 50% of the cells (CTC50 under the assay conditions. Venoms of C. rhodostoma (2.6 µg/mL, 1.4 µg/mL and O. hannah were the most cytotoxic (3.8 µg/mL, 1.7 µg/mL whereas N. siamensis venom showed the least cytotoxicity (51.9 µg/mL, 45.7 µg/mL against Vero and MDCK cells, respectively. All the viper venoms showed higher cytotoxic potency towards both Vero and MDCK cell lines, in comparison to krait and cobra venoms. E. schistosa did not cause cytotoxicity towards MDCK or Vero cells at the tested concentrations. The cytotoxicity correlates well with the known differences in the composition of venoms from cobras, kraits, vipers and sea snakes.

  6. Snake oil and venoms for medical research

    Science.gov (United States)

    Wolpert, H. D.

    2011-04-01

    Some think that using derivatives of snake venom for medical purposes is the modern version of snake oil but they are seriously misjudging the research potentials of some of these toxins in medicines of the 2000's. Medical trials, using some of the compounds has proven their usefulness. Several venoms have shown the possibilities that could lead to anticoagulants, helpful in heart disease. The blood clotting protein from the taipan snake has been shown to rapidly stop excessive bleeding. The venom from the copperhead may hold an answer to breast cancer. The Malaysian pit viper shows promise in breaking blood clots. Cobra venom may hold keys to finding cures for Parkinson's disease and Alzheimer's. Rattlesnake proteins from certain species have produced blood pressure medicines. Besides snake venoms, venom from the South American dart frog, mollusks (i.e. Cone Shell Snail), lizards (i.e. Gila Monster & Komodo Dragon), some species of spiders and tarantulas, Cephalopods, mammals (i.e. Platypus & Shrews), fish (i.e. sting rays, stone fish, puffer fish, blue bottle fish & box jelly fish), intertidal marine animals (echinoderms)(i.e. Crown of Thorn Star Fish & Flower Urchin) and the Honeybee are being investigated for potential medical benefits.

  7. Status of Pituophis ruthveni (Louisiana pine snake)

    Science.gov (United States)

    D. Craig Rudolph; Shirley J. Burgdorf; Richard R. Schaefer; Richard N. Conner; Ricky W. Maxey

    2006-01-01

    Extensive trapping surveys across the historical range of Pituophis ruthveni (Louisiana Pine Snake) suggest that extant populations are extremely small and limited to remnant patches of suitable habitat in a highly fragmented landscape. Evaluation of habitat at all known historical localities of P. ruthveni documents the widespread...

  8. A Schoolwide Endeavor: Our Exquisite Snake

    Science.gov (United States)

    Hoffman, Anne Marie

    2009-01-01

    The author was originally inspired by "The Exquisite Snake" exhibit she saw at a local museum. Two hundred contemporary artists contributed to this exhibit, which was an adaptation of the old parlor game called "The Exquisite Corpse" that Surrealist artists used to play in the late 1920s and '30s. The author just loved this idea and decided to…

  9. Ontogenetic shifts of heart position in snakes.

    Science.gov (United States)

    Lillywhite, Harvey B; Lillywhite, Steven M

    2017-08-01

    Heart position relative to total body length (TL) varies among snakes, with anterior hearts in arboreal species and more centrally located hearts in aquatic or ground-dwelling species. Anterior hearts decrease the cardiac work associated with cranial blood flow and minimize drops in cranial pressure and flow during head-up climbing. Here, we investigate whether heart position shifts intraspecifically during ontogenetic increases in TL. Insular Florida cottonmouth snakes, Agkistrodon conanti, are entirely ground-dwelling and have a mean heart position that is 33.32% TL from the head. In contrast, arboreal rat snakes, Pantherophis obsoleta, of similar lengths have a mean heart position that is 17.35% TL from the head. In both species, relative heart position shifts craniad during ontogeny, with negative slopes = -.035 and -.021% TL/cm TL in Agkistrodon and Pantherophis, respectively. Using a large morphometric data set available for Agkistrodon (N = 192 individuals, 23-140 cm TL), we demonstrate there is an anterior ontogenetic shift of the heart position within the trunk (= 4.56% trunk length from base of head to cloacal vent), independent of head and tail allometry which are both negative. However, in longer snakes > 100 cm, the heart position reverses and shifts caudally in longer Agkistrodon but continues toward the head in longer individuals of Pantherophis. Examination of data sets for two independent lineages of fully marine snakes (Acrochordus granulatus and Hydrophis platurus), which do not naturally experience postural gravity stress, demonstrate both ontogenetic patterns for heart position that are seen in the terrestrial snakes. The anterior migration of the heart is greater in the terrestrial species, even if TL is standardized to that of the longer P. obsoleta, and compensates for about 5 mmHg gravitational pressure head if they are fully upright. © 2017 Wiley Periodicals, Inc.

  10. Snake instability of dark solitons in fermionic superfluids

    Science.gov (United States)

    Cetoli, A.; Brand, J.; Scott, R. G.; Dalfovo, F.; Pitaevskii, L. P.

    2013-10-01

    We present numerical calculations of the snake instability in a Fermi superfluid within the Bogoliubov-de Gennes theory of the Bose-Einstein condensate (BEC) to BCS crossover using the random-phase approximation complemented by time-dependent simulations. We examine the snaking behavior across the crossover and quantify the time scale and length scale of the instability. While the dynamics shows extensive snaking before eventually producing vortices and sound on the BEC side of the crossover, the snaking dynamics is preempted by decay into sound due to pair breaking in the deep BCS regime. At the unitarity limit, hydrodynamic arguments allow us to link the rate of snaking to the experimentally observable ratio of inertial to physical mass of the soliton. In this limit we witness an unresolved discrepancy between our numerical estimates for the critical wave number of suppression of the snake instability and recent experimental observations with an ultracold Fermi gas.

  11. Pathophysiological significance and therapeutic applications of snake venom protease inhibitors.

    Science.gov (United States)

    Thakur, Rupamoni; Mukherjee, Ashis K

    2017-06-01

    Protease inhibitors are important constituents of snake venom and play important roles in the pathophysiology of snakebite. Recently, research on snake venom protease inhibitors has provided valuable information to decipher the molecular details of various biological processes and offer insight for the development of some therapeutically important molecules from snake venom. The process of blood coagulation and fibrinolysis, in addition to affecting platelet function, are well known as the major targets of several snake venom protease inhibitors. This review summarizes the structure-functional aspects of snake venom protease inhibitors that have been described to date. Because diverse biological functions have been demonstrated by protease inhibitors, a comparative overview of their pharmacological and pathophysiological properties is also highlighted. In addition, since most snake venom protease inhibitors are non-toxic on their own, this review evaluates the different roles of individual protease inhibitors that could lead to the identification of drug candidates and diagnostic molecules. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Smart Material-Actuated Flexible Tendon-Based Snake Robot

    Directory of Open Access Journals (Sweden)

    Mohiuddin Ahmed

    2016-05-01

    Full Text Available A flexible snake robot has better navigation ability compare with the existing electrical motor-based rigid snake robot, due to its excellent bending capability during navigation inside a narrow maze. This paper discusses the modelling, simulation and experiment of a flexible snake robot. The modelling consists of the kinematic analysis and the dynamic analysis of the snake robot. A platform based on the Incompletely Restrained Positioning Mechanism (IRPM is proposed, which uses the external force provided by a compliant flexible beam in each of the actuators. The compliant central column allows the configuration to achieve three degrees of freedom (3DOFs with three tendons. The proposed flexible snake robot has been built using smart material, such as electroactive polymers (EAPs, which can be activated by applying power to it. Finally, the physical prototype of the snake robot has been built. An experiment has been performed in order to justify the proposed model.

  13. The Lurking Snake in the Grass: Interference of Snake Stimuli in Visually Taxing Conditions

    Directory of Open Access Journals (Sweden)

    Sandra Cristina Soares

    2012-04-01

    Full Text Available Based on evolutionary considerations, it was hypothesized that humans have been shaped to easily spot snakes in visually cluttered scenes that might otherwise hide camouflaged snakes. This hypothesis was tested in a visual search experiment in which I assessed automatic attention capture to evolutionarily-relevant distractor stimuli (snakes, in comparison with another animal which is also feared but where this fear has a disputed evolutionary origin (spiders, and neutral stimuli (mushrooms. Sixty participants were engaged in a task that involved the detection of a target (a bird among pictures of fruits. Unexpectedly, on some trials, a snake, a spider, or a mushroom replaced one of the fruits. The question of interest was whether the distracting stimuli slowed the reaction times for finding the target (the bird to different degrees. Perceptual load of the task was manipulated by increments in the set size (6 or 12 items on different trials. The findings showed that snake stimuli were processed preferentially, particularly under conditions where attentional resources were depleted, which reinforced the role of this evolutionarily-relevant stimulus in accessing the visual system (Isbell, 2009.

  14. Monkey pulvinar neurons fire differentially to snake postures.

    Science.gov (United States)

    Le, Quan Van; Isbell, Lynne A; Matsumoto, Jumpei; Le, Van Quang; Hori, Etsuro; Tran, Anh Hai; Maior, Rafael S; Tomaz, Carlos; Ono, Taketoshi; Nishijo, Hisao

    2014-01-01

    There is growing evidence from both behavioral and neurophysiological approaches that primates are able to rapidly discriminate visually between snakes and innocuous stimuli. Recent behavioral evidence suggests that primates are also able to discriminate the level of threat posed by snakes, by responding more intensely to a snake model poised to strike than to snake models in coiled or sinusoidal postures (Etting and Isbell 2014). In the present study, we examine the potential for an underlying neurological basis for this ability. Previous research indicated that the pulvinar is highly sensitive to snake images. We thus recorded pulvinar neurons in Japanese macaques (Macaca fuscata) while they viewed photos of snakes in striking and non-striking postures in a delayed non-matching to sample (DNMS) task. Of 821 neurons recorded, 78 visually responsive neurons were tested with the all snake images. We found that pulvinar neurons in the medial and dorsolateral pulvinar responded more strongly to snakes in threat displays poised to strike than snakes in non-threat-displaying postures with no significant difference in response latencies. A multidimensional scaling analysis of the 78 visually responsive neurons indicated that threat-displaying and non-threat-displaying snakes were separated into two different clusters in the first epoch of 50 ms after stimulus onset, suggesting bottom-up visual information processing. These results indicate that pulvinar neurons in primates discriminate between poised to strike from those in non-threat-displaying postures. This neuronal ability likely facilitates behavioral discrimination and has clear adaptive value. Our results are thus consistent with the Snake Detection Theory, which posits that snakes were instrumental in the evolution of primate visual systems.

  15. Monkey pulvinar neurons fire differentially to snake postures.

    Directory of Open Access Journals (Sweden)

    Quan Van Le

    Full Text Available There is growing evidence from both behavioral and neurophysiological approaches that primates are able to rapidly discriminate visually between snakes and innocuous stimuli. Recent behavioral evidence suggests that primates are also able to discriminate the level of threat posed by snakes, by responding more intensely to a snake model poised to strike than to snake models in coiled or sinusoidal postures (Etting and Isbell 2014. In the present study, we examine the potential for an underlying neurological basis for this ability. Previous research indicated that the pulvinar is highly sensitive to snake images. We thus recorded pulvinar neurons in Japanese macaques (Macaca fuscata while they viewed photos of snakes in striking and non-striking postures in a delayed non-matching to sample (DNMS task. Of 821 neurons recorded, 78 visually responsive neurons were tested with the all snake images. We found that pulvinar neurons in the medial and dorsolateral pulvinar responded more strongly to snakes in threat displays poised to strike than snakes in non-threat-displaying postures with no significant difference in response latencies. A multidimensional scaling analysis of the 78 visually responsive neurons indicated that threat-displaying and non-threat-displaying snakes were separated into two different clusters in the first epoch of 50 ms after stimulus onset, suggesting bottom-up visual information processing. These results indicate that pulvinar neurons in primates discriminate between poised to strike from those in non-threat-displaying postures. This neuronal ability likely facilitates behavioral discrimination and has clear adaptive value. Our results are thus consistent with the Snake Detection Theory, which posits that snakes were instrumental in the evolution of primate visual systems.

  16. Physical mechanisms of control of gliding in flying snakes

    OpenAIRE

    Jafari, Farid

    2017-01-01

    Flying snakes possess a sophisticated gliding ability with a unique aerial behavior, in which they flatten their body to make a roughly triangular cross-sectional shape to produce lift and gain horizontal acceleration. Also, the snakes assume an S-like posture and start to undulate by sending traveling waves down the body. The present study aims to answer how the snakes are able to control their glide trajectory and remain stable without any specialized flight surfaces. Undulation is the most...

  17. A massive infestation of sea snakes by cymothoid isopods.

    Science.gov (United States)

    Saravanakumar, A; Balasubramanian, T; Raja, K; Trilles, Jean-Paul

    2012-06-01

    In this study, a massive infestation of the sea snake Enhydrina schistosa by the cymothoid isopod Nerocila serra, commonly parasitizing fishes, is reported for the first time from India. This isopod was found attached on the different parts of the body of the snake. According to the month, the parasitic prevalence ranged from 30.8 to 55.3%, increasing during the monsson period. It was higher in female than in male snakes.

  18. Genetic assemblage of Sarcocystis spp. in Malaysian snakes

    OpenAIRE

    Lau, Yee Ling; Chang, Phooi Yee; Subramaniam, Vellayan; Ng, Yit Han; Mahmud, Rohela; Ahmad, Arine Fadzlun; Fong, Mun Yik

    2013-01-01

    Background Sarcocystis species are protozoan parasites with a wide host range including snakes. Although there were several reports of Sarcocytis species in snakes, their distribution and prevalence are still not fully explored. Methods In this study, fecal specimens of several snake species in Malaysia were examined for the presence of Sarcocystis by PCR of 18S rDNA sequence. Microscopy examination of the fecal specimens for sporocysts was not carried as it was difficult to determine the spe...

  19. Molecular evidence of Sarcocystis species in captive snakes in Japan.

    Science.gov (United States)

    Abe, Niichiro; Matsubara, Katsuki; Tamukai, Kenichi; Miwa, Yasutsugu; Takami, Kazutoshi

    2015-08-01

    Sarcocystis nesbitti, using snakes as the definitive host, is a causative agent of acute human muscular sarcocystosis in Malaysia. Therefore, it is important to explore the distribution and prevalence of S. nesbitti in snakes. Nevertheless, epizootiological information of S. nesbitti in snakes remains insufficient because few surveys have assessed Sarcocystis infection in snakes in endemic countries. In Japan, snakes are popular exotic pet animals that are imported from overseas, but the degree of Sarcocystis infection in them remains unclear. The possibility exists that muscular sarcocystosis by S. nesbitti occurs in contact with captive snakes in non-endemic countries. For a total of 125 snake faecal samples from 67 snake species collected at animal hospitals, pet shops and a zoo, this study investigated the presence of Sarcocystis using polymerase chain reaction (PCR) for the 18S ribosomal RNA gene (18S rDNA). Four (3.2%) faecal samples were positive by PCR. Phylogenetic analysis of the 18S rDNA sequences obtained from four amplification products revealed one isolate from a beauty snake (Elaphe taeniura), Sarcocystis zuoi, which uses rat snakes as the definitive host. The isolate from a Macklot's python (Liasis mackloti) was closely related with unidentified Sarcocystis sp. from reticulated pythons in Malaysia. The remaining two isolates from tree boas (Corallus spp.) were closely related with Sarcocystis lacertae, Sarcocystis gallotiae and unidentified Sarcocystis sp. from smooth snakes, Tenerife lizards and European shrews, respectively. This report is the first of a study examining the distribution of Sarcocystis species in captive snakes in Japan.

  20. Texas coral snake (Micrurus tener) bites.

    Science.gov (United States)

    Morgan, David L; Borys, Douglas J; Stanford, Rhandi; Kjar, Dean; Tobleman, William

    2007-02-01

    The clinical features of bites from Texas coral snakes (Micrurus tener) have not been well studied. Our goal was to review the largest number of victims of Texas coral snakebites to determine their characteristics, effects, treatment, and outcome. Retrospective case series of Micrurus tener exposures reported to the Texas Poison Center Network from 2000 to 2004. Eighty-two patients were included in the analysis. Most (57.3%) were 18 to 49-year-old men. Almost 90% had local swelling, pain, erythema, or paresthesias. Only 7.3% had systemic effects, and none of these were severe. Over half received coral snake antivenin, and 15.9% were given opioids for pain. No patient died and no patient required mechanical ventilation due to hypoventilation from the snakebite. There were more local findings and less severe systemic effects than previously reported. Antivenin is not needed for most of these patients, and opioids may be administered safely.

  1. Predator cognition permits imperfect coral snake mimicry.

    Science.gov (United States)

    Kikuchi, David W; Pfennig, David W

    2010-12-01

    Batesian mimicry is often imprecise. An underexplored explanation for imperfect mimicry is that predators might not be able to use all dimensions of prey phenotype to distinguish mimics from models and thus permit imperfect mimicry to persist. We conducted a field experiment to test whether or not predators can distinguish deadly coral snakes (Micrurus fulvius) from nonvenomous scarlet kingsnakes (Lampropeltis elapsoides). Although the two species closely resemble one another, the order of colored rings that encircle their bodies differs. Despite this imprecise mimicry, we found that L. elapsoides that match coral snakes in other respects are not under selection to match the ring order of their model. We suggest that L. elapsoides have evolved only those signals necessary to deceive predators. Generally, imperfect mimicry might suffice if it exploits limitations in predator cognitive abilities.

  2. Reading color barcodes using visual snakes.

    Energy Technology Data Exchange (ETDEWEB)

    Schaub, Hanspeter (ORION International Technologies, Albuquerque, NM)

    2004-05-01

    Statistical pressure snakes are used to track a mono-color target in an unstructured environment using a video camera. The report discusses an algorithm to extract a bar code signal that is embedded within the target. The target is assumed to be rectangular in shape, with the bar code printed in a slightly different saturation and value in HSV color space. Thus, the visual snake, which primarily weighs hue tracking errors, will not be deterred by the presence of the color bar codes in the target. The bar code is generate with the standard 3 of 9 method. Using this method, the numeric bar codes reveal if the target is right-side-up or up-side-down.

  3. Soft Snakes: Construction, Locomotion, and Control

    Science.gov (United States)

    Branyan, Callie; Courier, Taylor; Fleming, Chloe; Remaley, Jacquelin; Hatton, Ross; Menguc, Yigit

    We fabricated modular bidirectional silicone pneumatic actuators to build a soft snake robot, applying geometric models of serpenoid swimmers to identify theoretically optimal gaits to realize serpentine locomotion. With the introduction of magnetic connections and elliptical cross-sections in fiber-reinforced modules, we can vary the number of continuum segments in the snake body to achieve more supple serpentine motion in a granular media. The performance of these gaits is observed using a motion capture system and efficiency is assessed in terms of pressure input and net displacement. These gaits are optimized using our geometric soap-bubble method of gait optimization, demonstrating the applicability of this tool to soft robot control and coordination.

  4. Serpents in jars: the snake wine industry in Vietnam

    Directory of Open Access Journals (Sweden)

    R. Somaweera

    2010-10-01

    Full Text Available Exploitation of snakes in Vietnam takes place for different purposes, and among them the snake wine industry is prominent but has received far less attention than other dealings, such as the pet trade. Despite widespread commercialisation there is a general lack of information about this snake trade, which makes it difficult to evaluate its magnitude and impact on snake populations. This study documents the use of snakes in snake wine in four cities in Vietnam through surveys conducted in 127 locations selling snake wine in September 2009. This study provides a list of species used along with the number of individuals observed. While none of the species involved are listed in the IUCN Red List, seven species are listed in the Vietnam Red Data Book, of which five are regulated by CITES. On the other hand, the most abundant species used in the trade, Xenochrophis flavipunctatus, is not listed in any conservation document. The popularity and economic importance of snakes in the form of snake wine demonstrates the need for the development of sustainable use programs for these species.

  5. A fatal cobra-bite in a snake expert.

    Science.gov (United States)

    Hossain, M Z; Atiqullah, S; Saha, A C; Chowdhury, A J; Jahangir, K M; Faiz, M A

    2010-04-01

    A 35-year-old so called snake-expert from Thakurgaon district was admitted in Medicine department of Rangpur Medical College Hospital (RpMCH), Rangpur, Bangladesh on 2nd November 2007 with history of bites by a cobra snake. He was famous for his outstanding works to establish a snake farm first ever in Bangladesh. He had a collection of more than one hundred snakes of different species. He used to hatch eggs of the snakes, feed the young-snakes, collect venoms and sell those. Everyday many visitors used to visit his farm to watch exciting games with poisonous snakes. Several satellite television (TV) channels and some daily newspapers had covered him on different occasions. He was accidentally bitten by a newly caught hungry cobra snake while recording for a satellite TV channel. Following bites he was brought to the hospital three and a half hours later. By that time, neurotoxicity developed. Repeated doses of Anti Snake Venom (ASV) along with respiratory support and other supportive cares were provided. Despite utmost care feasible at RpMCH, patient expired around 49 hours later.

  6. Snake bite in Northwest Iran: A retrospective study

    Directory of Open Access Journals (Sweden)

    Leila Eslamian

    2016-08-01

    Full Text Available Introduction: bite affects about 2 million people every year, with more than 100000 mortalities annually. A person bitten by a snake represents a variety of symptoms. Snake bite might be asymptomatic or with mild local symptoms or even could lead to tissue damage and rapid death. This study aimed to investigate characteristics of snake bite in Northwest Iran. Methods: In this retrospective study, medical records of all patients with final diagnosis of snake bite who were admitted to Sina Clinical-Educational Center, the referral center for envenomation in Northwest Iran were investigated from 2002 to 2012. Demographic information and laboratory findings were collected using a checklist. Results: During a 10 year period, 160 individuals with snake bite were admitted, of which 128 (77.6% were male. With regard to occupation, farmers accounted for the largest portion (n = 57, 34.6%. The most prevalent sites bitten by snakes were right hand (25.5% and left leg (24.8%. Fifty-seven patients (34.5% had leukocytosis and four (2.4% had coagulopathy. Pain and swelling were two main complaints, with vomiting, dizziness, and tingling in extremities coming afterwards. Conclusion: Because snake bite is one of the most important emergencies presenting to emergency department and Iran’s geographic status bears wide spectrum of poisonous snakes, this study was performed to further explore the clinical and epidemiologic details of snake bite.

  7. Molecular Identification of Cryptosporidium Species from Pet Snakes in Thailand.

    Science.gov (United States)

    Yimming, Benjarat; Pattanatanang, Khampee; Sanyathitiseree, Pornchai; Inpankaew, Tawin; Kamyingkird, Ketsarin; Pinyopanuwat, Nongnuch; Chimnoi, Wissanuwat; Phasuk, Jumnongjit

    2016-08-01

    Cryptosporidium is an important pathogen causing gastrointestinal disease in snakes and is distributed worldwide. The main objectives of this study were to detect and identify Cryptosporidium species in captive snakes from exotic pet shops and snake farms in Thailand. In total, 165 fecal samples were examined from 8 snake species, boa constrictor (Boa constrictor constrictor), corn snake (Elaphe guttata), ball python (Python regius), milk snake (Lampropeltis triangulum), king snake (Lampropeltis getula), rock python (Python sebae), rainbow boa (Epicrates cenchria), and carpet python (Morelia spilota). Cryptosporidium oocysts were examined using the dimethyl sulfoxide (DMSO)-modified acid-fast staining and a molecular method based on nested-PCR, PCR-RFLP analysis, and sequencing amplification of the SSU rRNA gene. DMSO-modified acid-fast staining revealed the presence of Cryptosporidium oocysts in 12 out of 165 (7.3%) samples, whereas PCR produced positive results in 40 (24.2%) samples. Molecular characterization indicated the presence of Cryptosporidium parvum (mouse genotype) as the most common species in 24 samples (60%) from 5 species of snake followed by Cryptosporidium serpentis in 9 samples (22.5%) from 2 species of snake and Cryptosporidium muris in 3 samples (7.5%) from P. regius.

  8. Primary homologies of the circumorbital bones of snakes.

    Science.gov (United States)

    Palci, Alessandro; Caldwell, Michael W

    2013-09-01

    Some snakes have two circumorbital ossifications that in the current literature are usually referred to as the postorbital and supraorbital. We review the arguments that have been proposed to justify this interpretation and provide counter-arguments that reject those conjectures of primary homology based on the observation of 32 species of lizards and 81 species of snakes (both extant and fossil). We present similarity arguments, both topological and structural, for reinterpretation of the primary homologies of the dorsal and posterior orbital ossifications of snakes. Applying the test of similarity, we conclude that the posterior orbital ossification of snakes is topologically consistent as the homolog of the lacertilian jugal, and that the dorsal orbital ossification present in some snakes (e.g., pythons, Loxocemus, and Calabaria) is the homolog of the lacertilian postfrontal. We therefore propose that the terms postorbital and supraorbital should be abandoned as reference language for the circumorbital bones of snakes, and be replaced with the terms jugal and postfrontal, respectively. The primary homology claim for the snake "postorbital" fails the test of similarity, while the term "supraorbital" is an unnecessary and inaccurate application of the concept of a neomorphic ossification, for an element that passes the test of similarity as a postfrontal. This reinterpretation of the circumorbital bones of snakes is bound to have important repercussions for future phylogenetic analyses and consequently for our understanding of the origin and evolution of snakes. Copyright © 2013 Wiley Periodicals, Inc.

  9. Endogenous hepadnaviruses, bornaviruses and circoviruses in snakes.

    Science.gov (United States)

    Gilbert, C; Meik, J M; Dashevsky, D; Card, D C; Castoe, T A; Schaack, S

    2014-09-22

    We report the discovery of endogenous viral elements (EVEs) from Hepadnaviridae, Bornaviridae and Circoviridae in the speckled rattlesnake, Crotalus mitchellii, the first viperid snake for which a draft whole genome sequence assembly is available. Analysis of the draft assembly reveals genome fragments from the three virus families were inserted into the genome of this snake over the past 50 Myr. Cross-species PCR screening of orthologous loci and computational scanning of the python and king cobra genomes reveals that circoviruses integrated most recently (within the last approx. 10 Myr), whereas bornaviruses and hepadnaviruses integrated at least approximately 13 and approximately 50 Ma, respectively. This is, to our knowledge, the first report of circo-, borna- and hepadnaviruses in snakes and the first characterization of non-retroviral EVEs in non-avian reptiles. Our study provides a window into the historical dynamics of viruses in these host lineages and shows that their evolution involved multiple host-switches between mammals and reptiles. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  10. Development of snake-directed antipredator behavior by wild white-faced capuchin monkeys: I. Snake-species discrimination.

    Science.gov (United States)

    Meno, Whitney; Coss, Richard G; Perry, Susan

    2013-03-01

    Young animals are known to direct alarm calls at a wider range of species than adults. Our field study examined age-related differences in the snake-directed antipredator behavior of infant, juvenile, and adult white-faced capuchin monkeys (Cebus capucinus) in terms of alarm calling, looking behavior, and aggressive behavior. In the first experiment, we exposed infant and juvenile white-faced capuchins to realistic-looking inflatable models of their two snake predators, the boa constrictior (Boa constrictor) and neotropical rattlesnake (Crotalus durissus) and a white airplane as a novel control. In the second experiment, infants, juveniles, and adults were presented photographic models of a coiled boa constrictor, rattlesnake, indigo snake (Drymarchon corais), a noncapuchin predator, and a white snake-like model. We found that antipredator behavior changed during the immature stage. Infants as young as 4 months old were able to recognize snakes and display antipredator behavior, but engaged in less snake-model discrimination than juveniles. All age classes exhibited a lower response to the white snake-like model, indicating that the absence of color and snake-scale patterns affected snake recognition. Infants also showed a higher level of vigilance after snake-model detection as exhibited by a higher proportion of time spent looking and head cocking at the models. Aggressive antipredator behavior was found in all age classes, but was more prevalent in juveniles and adults than infants. This study adds to the knowledge of development of antipredator behavior in primates by showing that, although alarm calling behavior and predator recognition appear at a very young age in capuchins, snake-species discrimination does not become apparent until the juvenile stage. © 2012 Wiley Periodicals, Inc.

  11. A Systematic Review of the Hispaniolan Snake Genus Hypsirhynchus

    NARCIS (Netherlands)

    Schwartz, Albert

    1971-01-01

    One of the least known of the endemic Hispaniolan colubrid snake genera is Hypsirhynchus. The genus was proposed by GUNTHER (1858) for one specimen of a new snake, purportedly from the island of Barbados, to which he gave the name H. ferox. COPE (1862) later described H. scalaris from Hispaniola

  12. Snake mortality associated with late season radio-transmitter implantation

    Science.gov (United States)

    D. Craig Rudolph; Shirley J. Burgdorf; Richard R. Schaefer; Richard N. Conner; Robert T. Zappalorth

    1998-01-01

    Radio-telemetry is an increasingly used procedure to obtain data on the biology of free-living snakes (Reinert 1992, 1994). In Texas and Louisiana we have been using the surgical technique of Weatherhead and Anderka (1984) to implant transmitters in timber rattlesnakes (Crotalus horridus) and Louisiana pine snakes (Pituophis melanoleucus...

  13. An Unusual Case of Acute Asthma after Snake Bite | Ikuabe ...

    African Journals Online (AJOL)

    Background Although the cytolytic, neurotoxic and haemolytic actions of snake venoms are well known, the ability of snake venom to induce asthma (as a distinct entity from just difficulty in breathing) is not previously reported in the literature. Methods The case records of the patient in the index case and a review of existing ...

  14. Skin lipid structure controls water permeability in snake molts.

    Science.gov (United States)

    Torri, Cristian; Mangoni, Alfonso; Teta, Roberta; Fattorusso, Ernesto; Alibardi, Lorenzo; Fermani, Simona; Bonacini, Irene; Gazzano, Massimo; Burghammer, Manfred; Fabbri, Daniele; Falini, Giuseppe

    2014-01-01

    The role of lipids in controlling water exchange is fundamentally a matter of molecular organization. In the present study we have observed that in snake molt the water permeability drastically varies among species living in different climates and habitats. The analysis of molts from four snake species: tiger snake, Notechis scutatus, gabon viper, Bitis gabonica, rattle snake, Crotalus atrox, and grass snake, Natrix natrix, revealed correlations between the molecular composition and the structural organization of the lipid-rich mesos layer with control in water exchange as a function of temperature. It was discovered, merging data from micro-diffraction and micro-spectroscopy with those from thermal, NMR and chromatographic analyses, that this control is generated from a sophisticated structural organization that changes size and phase distribution of crystalline domains of specific lipid molecules as a function of temperature. Thus, the results of this research on four snake species suggest that in snake skins different structured lipid layers have evolved and adapted to different climates. Moreover, these lipid structures can protect, "safety", the snakes from water lost even at temperatures higher than those of their usual habitat. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Emerging fungal pathogen Ophidiomyces ophiodiicola in wild European snakes

    Science.gov (United States)

    Franklinos, Lydia H. V.; Lorch, Jeffrey M.; Bohuski, Elizabeth A.; Rodriguez-Ramos Fernandez, Julia; Wright, Owen; Fitzpatrick, Liam; Petrovan, Silviu; Durrant, Chris; Linton, Chris; Baláž, Vojtech; Cunningham, Andrew A; Lawson, Becki

    2017-01-01

    Snake fungal disease (SFD) is an emerging disease of conservation concern in eastern North America. Ophidiomyces ophiodiicola, the causative agent of SFD, has been isolated from over 30 species of wild snakes from six families in North America. Whilst O. ophiodiicola has been isolated from captive snakes outside North America, the pathogen has not been reported from wild snakes elsewhere. We screened 33 carcasses and 303 moulted skins from wild snakes collected from 2010–2016 in Great Britain and the Czech Republic for the presence of macroscopic skin lesions and O. ophiodiicola. The fungus was detected using real-time PCR in 26 (8.6%) specimens across the period of collection. Follow up culture and histopathologic analyses confirmed that both O. ophiodiicola and SFD occur in wild European snakes. Although skin lesions were mild in most cases, in some snakes they were severe and were considered likely to have contributed to mortality. Culture characterisations demonstrated that European isolates grew more slowly than those from the United States, and phylogenetic analyses indicated that isolates from European wild snakes reside in a clade distinct from the North American isolates examined. These genetic and phenotypic differences indicate that the European isolates represent novel strains of O. ophiodiicola. Further work is required to understand the individual and population level impact of this pathogen in Europe.

  16. The snakes of Ghana: myth, science and reality | Attuquayefio ...

    African Journals Online (AJOL)

    Snakes have been symbols of fear and hostility to most human societies throughout the ages, largely due to their perceived deceit of Adam and Eve to eat the forbidden fruit in the biblical Garden of Eden, as well as to the general lack of knowledge and appreciation of snake biology and behaviour. This has resulted in the ...

  17. Assessment of human-snake interaction and its outcomes in ...

    African Journals Online (AJOL)

    Background: Human-snake interactions has always been associated with different outcomes. This cross-sectional study was conducted to assess the human-snake interaction and its outcomes in Monduli District, northern Tanzania. Methods: Data collection was done through questionnaires, key informants interviews and ...

  18. Snake bite in Gombe | Mustapha | Highland Medical Research Journal

    African Journals Online (AJOL)

    Aims: Snake bite is an important cause of morbidity and mortality in Nigeria as in many parts of the tropics. This study was undertaken to determine the prevalence and the clinical pattern of snake bite in Gombe. Methods: Two hundred and seven (207) cases of snakebite admitted at the State Specialist Hospital Gombe over ...

  19. Major upper limb amputation after Snake Bite Gangrene | Ajibade ...

    African Journals Online (AJOL)

    Major lower limb amputations following snake bite gangrene have been reported from the savannah belt of Nigeria. In bites delivered to the upper limb, amputations are often of the digits (minor amputations). We report the case of a male farmer who had an above elbow amputation after a snake bite to the hand. Explanation ...

  20. Snakes of Sulawesi: checklist, key and additional Biogeographical remarks

    NARCIS (Netherlands)

    Bosch, in den H.A.J.

    1985-01-01

    A checklist with concise synonymy and a key to the snakes of Sulawesi is presented, comprising 63 species in 38 genera; 3 subspecies and 15 species, of which one constitutes a monotypic genus, are considered endemic. There is a strong Indo-Malayan relationship. Sea-snakes and Candoia carinata

  1. Snake scales, partial exposure, and the Snake Detection Theory: A human event-related potentials study

    NARCIS (Netherlands)

    J.W. van Strien (Jan); L.A. Isbell (Lynne A.)

    2017-01-01

    textabstractStudies of event-related potentials in humans have established larger early posterior negativity (EPN) in response to pictures depicting snakes than to pictures depicting other creatures. Ethological research has recently shown that macaques and wild vervet monkeys respond strongly to

  2. Snake fungal disease caused by Ophidiomyces ophiodiicola in a free-ranging mud snake (Farancia abacura).

    Science.gov (United States)

    Last, Lisa A; Fenton, Heather; Gonyor-McGuire, Jessica; Moore, Matthew; Yabsley, Michael J

    2016-11-01

    Snake fungal disease is an emerging infectious disease caused by the fungus Ophidiomyces ophiodiicola leading to severe dermatitis and facial disfiguration in numerous free-ranging and captive snakes. A free-ranging mud snake (Farancia abacura) from Bulloch County, Georgia, was presented for autopsy because of facial swelling and emaciation. Extensive ulceration of the skin, which was especially severe on the head, and retained shed were noted on external examination. Microscopic examination revealed severe heterophilic dermatitis with intralesional fungal hyphae and arthroconidia consistent with O. ophiodiicola A skin sample incubated on Sabouraud dextrose agar yielded a white-to-tan powdery fungal culture that was confirmed to be O. ophiodiicola by polymerase chain reaction and sequence analysis. Heavy infestation with adult tapeworms (Ophiotaenia faranciae) was present within the intestine. Various bacterial and fungal species, interpreted to either be secondary invaders or postmortem contaminants, were associated with oral lesions. Although the role of these other organisms in the overall health of this individual is not known, factors such as concurrent infections or immunosuppression should be considered in order to better understand the overall manifestation of snake fungal disease, which remains poorly characterized in its host range and geographic distribution. © 2016 The Author(s).

  3. Optimal axes of Siberian snakes for polarized proton acceleration

    Directory of Open Access Journals (Sweden)

    Georg H. Hoffstaetter

    2004-12-01

    Full Text Available Accelerating polarized proton beams and storing them for many turns can lead to a loss of polarization when accelerating through energies where a spin rotation frequency is in resonance with orbit oscillation frequencies. First-order resonance effects can be avoided by installing Siberian snakes in the ring, devices which rotate the spin by 180° around the snake axis while not changing the beam’s orbit significantly. For large rings, several Siberian snakes are required. Here a criterion will be derived that allows one to find an optimal choice for the orientation of the snake axes. Rings with superperiod four are analyzed in detail, and the HERA proton ring is used as an example for approximate fourfold symmetry. The proposed arrangement of Siberian snakes matches their effects so that all spin-orbit coupling integrals vanish at all energies and therefore there is no first-order spin-orbit coupling at all for this choice, which I call snake matching. It will be shown that in general at least eight Siberian snakes are needed and that there are exactly four possibilities to arrange their axes. When the betatron phase advance between snakes is chosen suitably, four Siberian snakes can be sufficient. Since the spin motion depends on a particle’s trajectory, protons at different phase space positions generally have different spin directions. The time averaged polarization at each phase space point is parallel to the invariant spin field, and the spread of this spin field limits the polarization that can be stored. By the here presented choice of Siberian snakes this limit is completely eliminated up to first order in the transverse phase space coordinates. The invariant spin field and the amplitude-dependent spin tune are also computed without linearization to show the advantages of this choice of snakes. Ultimately, the goal of snake matching is to reduce the loss of polarization during the acceleration of the beam. To show that a favorable

  4. Stress-Strain Measurements of Semi-Aquatic Snake Lenses

    Science.gov (United States)

    Lama, Nisha; Norwood, David, , Dr.; Fontenot, Cliff, , Dr.; Wallace, Addison; Koduri, Mahitha; Allain, Rhett, , Dr.

    It is of interest to understand the mechanism by which semi-aquatic maintain visual acuity when moving from land to underwater. Toward that end, we are interested in the mechanical properties of snake lenses and how this might affect the ability of snakes to deform the lens and thus alter the lens power. In this presentation, we will present data taken with a force sensor and a rotary motion sensor to measure, in one shot, force versus displacement, from which we estimate mechanical properties of stress and strain of the eye lens of a water snake. We will compare the results from lenses freshly removed from snake to those that have been stored. More importantly though, we will compare results from one species of semi-aquatic snakes to the other species of interest

  5. Genetic assemblage of Sarcocystis spp. in Malaysian snakes.

    Science.gov (United States)

    Lau, Yee Ling; Chang, Phooi Yee; Subramaniam, Vellayan; Ng, Yit Han; Mahmud, Rohela; Ahmad, Arine Fadzlun; Fong, Mun Yik

    2013-09-09

    Sarcocystis species are protozoan parasites with a wide host range including snakes. Although there were several reports of Sarcocytis species in snakes, their distribution and prevalence are still not fully explored. In this study, fecal specimens of several snake species in Malaysia were examined for the presence of Sarcocystis by PCR of 18S rDNA sequence. Microscopy examination of the fecal specimens for sporocysts was not carried as it was difficult to determine the species of the infecting Sarcocystis. Of the 28 snake fecal specimens, 7 were positive by PCR. BLASTn and phylogenetic analyses of the amplified 18S rDNA sequences revealed the snakes were infected with either S. nesbitti, S. singaporensis, S. zuoi or undefined Sarcocystis species. This study is the first to report Sarcocystis infection in a cobra, and S. nesbitti in a reticulated python.

  6. Venomous snakebite in Thailand. I: Medically important snakes.

    Science.gov (United States)

    Chanhome, L; Cox, M J; Wilde, H; Jintakoon, P; Chaiyabutr, N; Sitprija, V

    1998-05-01

    Thailand has an abundance of venomous snakes. Among the neurotoxic family Elapidae, there are three species of the genus Naja (cobras), three of the genus Bungarus (kraits), and the king cobra of the genus Ophiophagus. Other Elapidae snakes in Thailand include sea snakes and Asian coral snakes of the genus Calliophis. They have potent venoms but rarely bite humans. Tissue and hemotoxic snakes are represented by family Viperidae, subfamilies Viperinae and Crotalinae. They remain an occupational hazard for farmers and rubber tappers, causing serious morbidity but only rare deaths, since competent treatment is now widely available throughout Thailand. Purified equine antivenin is manufactured locally for the monocled and Siamese spitting cobras (Naja kaouthia and N. siamensis), king cobra (Ophiophagus hannah), banded krait (Bungarus fasciatus), most green pit vipers (Trimeresurus sp.), Malayan pit viper (Calloselasma rhodostoma), and the Siamese Russell's viper (Daboia russelli siamensis).

  7. NEOPLASIA IN SNAKES AT ZOO ATLANTA DURING 1992-2012.

    Science.gov (United States)

    Page-Karjian, Annie; Hahne, Megan; Leach, Kate; Murphy, Hayley; Lock, Brad; Rivera, Samuel

    2017-06-01

    A retrospective study was conducted to review neoplasia of captive snakes in the Zoo Atlanta collection from 1992 to 2012. Of 255 snakes that underwent necropsy and histopathologic examination at Zoo Atlanta during the study period, 37 were observed with neoplasia at necropsy. In those 37 snakes, 42 neoplastic lesions of 18 primary cell types were diagnosed. Thirty-five of those neoplasms (83.3%) were malignant, and of those, 19 were of mesenchymal origin, whereas 14 were of epithelial origin. The median annual rate of neoplasia at necropsy was 12.5% (interquartile range = 2.8-19.5%) over the 21-yr study period. The mean estimated age at death for snakes with neoplasia was 13.2 yr (range, 1-24 yr). Investigating the incidence and clinical significance of neoplasia in captive snakes is vital for developing effective preventative and treatment regimes.

  8. Oxygenation properties and isoform diversity of snake hemoglobins

    DEFF Research Database (Denmark)

    Storz, Jay F.; Natarajan, Chandrasekhar; Moriyama, Hideaki

    2015-01-01

    Available data suggest that snake hemoglobins (Hbs) are characterized by a combination of unusual structural and functional properties relative to the Hbs of other amniote vertebrates, including oxygenation-linked tetramer- dimer dissociation. However, standardized comparative data are lacking...... for snake Hbs, and the Hb isoform composition of snake red blood cells has not been systematically characterized. Here we present the results of an integrated analysis of snake Hbs and the underlying - and -type globin genes to characterize 1) Hb isoform composition of definitive erythrocytes, and 2......) the oxygenation properties of isolated isoforms as well as composite hemolysates. We used species from three families as subjects for experimental studies of Hb function: South American rattlesnake, Crotalus durissus (Viperidae); Indian python, Python molurus (Pythonidae); and yellow-bellied sea snake, Pelamis...

  9. Snakes as hazards: modelling risk by chasing chimpanzees.

    Science.gov (United States)

    McGrew, William C

    2015-04-01

    Snakes are presumed to be hazards to primates, including humans, by the snake detection hypothesis (Isbell in J Hum Evol 51:1-35, 2006; Isbell, The fruit, the tree, and the serpent. Why we see so well, 2009). Quantitative, systematic data to test this idea are lacking for the behavioural ecology of living great apes and human foragers. An alternative proxy is snakes encountered by primatologists seeking, tracking, and observing wild chimpanzees. We present 4 years of such data from Mt. Assirik, Senegal. We encountered 14 species of snakes a total of 142 times. Almost two-thirds of encounters were with venomous snakes. Encounters occurred most often in forest and least often in grassland, and more often in the dry season. The hypothesis seems to be supported, if frequency of encounter reflects selective risk of morbidity or mortality.

  10. The ecological origins of snakes as revealed by skull evolution.

    Science.gov (United States)

    Da Silva, Filipe O; Fabre, Anne-Claire; Savriama, Yoland; Ollonen, Joni; Mahlow, Kristin; Herrel, Anthony; Müller, Johannes; Di-Poï, Nicolas

    2018-01-25

    The ecological origin of snakes remains amongst the most controversial topics in evolution, with three competing hypotheses: fossorial; marine; or terrestrial. Here we use a geometric morphometric approach integrating ecological, phylogenetic, paleontological, and developmental data for building models of skull shape and size evolution and developmental rate changes in squamates. Our large-scale data reveal that whereas the most recent common ancestor of crown snakes had a small skull with a shape undeniably adapted for fossoriality, all snakes plus their sister group derive from a surface-terrestrial form with non-fossorial behavior, thus redirecting the debate toward an underexplored evolutionary scenario. Our comprehensive heterochrony analyses further indicate that snakes later evolved novel craniofacial specializations through global acceleration of skull development. These results highlight the importance of the interplay between natural selection and developmental processes in snake origin and diversification, leading first to invasion of a new habitat and then to subsequent ecological radiations.

  11. The Narrow Fellow in the Grass: Human Infants Associate Snakes and Fear

    Science.gov (United States)

    DeLoache, Judy S.; LoBue, Vanessa

    2009-01-01

    Why are snakes such a common target of fear? One current view is that snake fear is one of several innate fears that emerge spontaneously. Another is that humans have an evolved predisposition to learn to fear snakes. In the first study reported here, 9- to 10-month-old infants showed no differential spontaneous reaction to films of snakes versus…

  12. Snake venoms in science and clinical medicine. 2. Applied immunology in snake venom research.

    Science.gov (United States)

    Theakston, R D

    1989-01-01

    Enzyme-linked immunosorbent assay (ELISA) is a very important tool for studying both the epidemiology and clinical effects of snake bite in man. For epidemiology ELISA depends on the development and persistence of specific humoral venom antibody in previous snake bite victims. In the Nigerian savanna 63% of previous bite victims possessed specific venom antibodies against Echis carinatus venom; in Ecuador, where there is a 5% annual mortality due to snake bite in a population of Waorani Indians, venom antibodies against a wide range of different venoms were identified in previous bite victims using ELISA. In certain areas it is often not possible, using the symptoms of envenoming, to determine which species of snake has bitten the patient. Field studies using ELISA in Nigeria and Thailand have been successful in establishing the species responsible for envenoming. Current studies are in progress on the development of a rapid immunoassay which should be capable of detecting the biting species within 5-10 min of sampling from the admission patient. This will be useful for the clinician as it will enable the rapid detection of the species responsible for envenoming and, therefore, the use of the correct antivenom. Experimental work on the development of new methods of antivenom production includes immunization of experimental animals with venom/liposome preparations, the preparation of venom antigens using monoclonal antibodies on affinity columns, and recombinant deoxyribonucleic acid technology. Liposomal immunization requires only a single injection of venom to obtain a rapid, high level and protective immune response. Venom liposomes may also be given orally resulting in a serum immunoglobulin G immune response in experimental animals. Use of such a system may eventually result in immunization of man in areas of high snake bite incidence and mortality.

  13. Public perceptions of snakes and snakebite management: implications for conservation and human health in southern Nepal.

    Science.gov (United States)

    Pandey, Deb Prasad; Subedi Pandey, Gita; Devkota, Kamal; Goode, Matt

    2016-06-02

    Venomous snakebite and its effects are a source of fear for people living in southern Nepal. As a result, people have developed a negative attitude towards snakes, which can lead to human-snake conflicts that result in killing of snakes. Attempting to kill snakes increases the risk of snakebite, and actual killing of snakes contributes to loss of biodiversity. Currently, snake populations in southern Nepal are thought to be declining, but more research is needed to evaluate the conservation status of snakes. Therefore, we assessed attitudes, knowledge, and awareness of snakes and snakebite by Chitwan National Park's (CNP) buffer zone (BZ) inhabitants in an effort to better understand challenges to snake conservation and snakebite management. The results of this study have the potential to promote biodiversity conservation and increase human health in southern Nepal and beyond. We carried out face-to-face interviews of 150 randomly selected CNP BZ inhabitants, adopting a cross-sectional mixed research design and structured and semi-structured questionnaires from January-February 2013. Results indicated that 43 % of respondents disliked snakes, 49 % would exterminate all venomous snakes, and 86 % feared snakes. Farmers were the most negative and teachers were the most ambivalent towards snakes. Respondents were generally unable to identify different snake species, and were almost completely unaware of the need of conserve snakes and how to prevent snakebites. Belief in a snake god, and the ability of snakes to absorb poisonous gases from the atmosphere were among many superstitions that appeared to predispose negativity towards snakes of BZ residents. People with predisposed negativity towards snakes were not proponents of snake conservation. Fear, negativity, ambivalence towards, and ignorance about, snakes and the need for snake conservation were strong indicators of the propensity to harm or kill snakes. It seems that if wanton killing of snakes continues

  14. Analysis, reconstruction and manipulation using arterial snakes

    KAUST Repository

    Li, Guo

    2010-01-01

    Man-made objects often consist of detailed and interleaving structures, which are created using cane, coils, metal wires, rods, etc. The delicate structures, although manufactured using simple procedures, are challenging to scan and reconstruct. We observe that such structures are inherently 1D, and hence are naturally represented using an arrangement of generating curves. We refer to the resultant surfaces as arterial surfaces. In this paper we approach for analyzing, reconstructing, and manipulating such arterial surfaces. The core of the algorithm is a novel deformable model, called arterial snake, that simultaneously captures the topology and geometry of the arterial objects. The recovered snakes produce a natural decomposition of the raw scans, with the decomposed parts often capturing meaningful object sections. We demonstrate the robustness of our algorithm on a variety of arterial objects corrupted with noise, outliers, and with large parts missing. We present a range of applications including reconstruction, topology repairing, and manipulation of arterial surfaces by directly controlling the underlying curve network and the associated sectional profiles, which are otherwise challenging to perform. © 2010 ACM.

  15. Mandibular osteosynthesis in a Boa constrictor snake

    Directory of Open Access Journals (Sweden)

    Jorge Luiz Costa Castro

    2014-02-01

    Full Text Available Nowadays are observed an increase in the finding of certain wild animals in urban areas, due to environmental changes caused by deforestation and economic use of natural areas. It causes disappearance of usual prey and forces these animals, including snakes, to migrate to urban areas, becoming vulnerable to injuries caused by aggressions, car accidents and capture. Mandibular and maxillar fractures are common in many animal species, representing about 3-6% of all bone fractures in dogs and cats. Mandibular trauma usually occurs as a result of fights, car accidents and improper handling and/or restraint, and fractures can be closed or open, clean or contaminated. The jaw is a flat bone with differences from the long bones that should be taken into consideration for successful treatment, being minimal muscle coverage and need to maintain occlusion factors that influence the definition of the best ostheosynthesis method. The methods of stabilization include using intramedullary pins, wires, external skeletal fixation, bone plate, and acrylic resin. Conventional bone plates are efficient but related to some complications, such as the necessity of muscular elevation and high risk of injuries to mandibular structures. This article describes the successful results of the application of plate and screws in the ostheosynthesis of a mandibular fracture in a female Boa constrictor snake with weight of 8.0 kg and length of 1.80 m, at the RIOZOO Foundation (Rio de Janeiro, RJ, Brazil.

  16. Superconducting Helical Snake Magnet for the AGS

    CERN Document Server

    Willen, Erich; Escallier, John; Ganetis, George; Ghosh, Arup; Gupta, Ramesh C; Harrison, Michael; Jain, Animesh K; Luccio, Alfredo U; MacKay, William W; Marone, Andrew; Muratore, Joseph F; Okamura, Masahiro; Plate, Stephen R; Roser, Thomas; Tsoupas, Nicholaos; Wanderer, Peter

    2005-01-01

    A superconducting helical magnet has been built for polarized proton acceleration in the Brookhaven AGS. This "partial Snake" magnet will help to reduce the loss of polarization of the beam due to machine resonances. It is a 3 T magnet some 1940 mm in magnetic length in which the dipole field rotates with a pitch of 0.2053 degrees/mm for 1154 mm in the center and a pitch of 0.3920 degrees/mm for 393 mm in each end. The coil cross-section is made of two slotted cylinders containing superconductor. In order to minimize residual offsets and deflections of the beam on its orbit through the Snake, a careful balancing of the coil parameters was necessary. In addition to the main helical coils, a solenoid winding was built on the cold bore tube inside the main coils to compensate for the axial component of the field that is experienced by the beam when it is off-axis in this helical magnet. Also, two dipole corrector magnets were placed on the same tube with the solenoid. A low heat leak cryostat was built so that t...

  17. Coral snake bites and envenomation in children: a case series.

    Science.gov (United States)

    Sasaki, Jun; Khalil, Paul A; Chegondi, Madhuradhar; Raszynski, Andre; Meyer, Keith G; Totapally, Balagangadhar R

    2014-04-01

    North America is home to 2 families of venomous snakes, Crotalinae (pit viper family) and Elapidae (coral snake family). Although there are several published reports describing and reviewing the management of pit viper snakebites in children, there are no recent similar publications detailing the clinical course and management of coral snake envenomation. Our case series describes the hospital course of children with coral snake bites admitted to our regional pediatric intensive care. We also reviewed prior published case reports of coral snake bites in the United States. We identified 4 patients with either confirmed or suspected coral snake envenomation from our hospital's records. In 2 cases, the snakebite occurred after apparent provocation. Antivenom was administered to 3 patients. The regional venom response team was consulted for management advice and supplied the antivenom. One patient had a prolonged hospital course, which was complicated by respiratory failure, bulbar palsy, and ataxia. All survived to discharge. Admission to pediatric intensive care is warranted after all Eastern coral snake bites. A specialized regional or national venom response team can be a useful resource for management advice and as a source of antivenom.

  18. Chemosensory age discrimination in the snake Boa constrictor (Serpentes: Boidae

    Directory of Open Access Journals (Sweden)

    Marianne Gabirot

    2012-12-01

    Full Text Available Many snakes are able to use their chemosensory system to detect scent of conspecifics, which is important in many social contexts. Age discrimination based on chemical cues may be especially important to ensure access to sexually mature potential partners. In this study, we used 24 individual Boa constrictor snakes (12 adults mature and 12 non-mature individuals that had been captured in different areas of Ecuador, and were maintained in captivity at the Vivarium of Quito. We used tongue-flick experiments to examine whether these snakes were able to discriminate between scents from mature and non-mature individuals. Results showed that B. constrictor snakes used chemical cues to recognize conspecifics and that the scent of individuals of different ages elicited chemosensory responses of different magnitudes. The scents from adult conspecifics elicited the quickest and highest chemosensory responses (i.e., short latency times and high tongue-flick rates, although we did not find differential responses to scent of males and females. The magnitude of the responses was lower to scent of sub adult individuals, and then even lower to scent of juvenile snakes, but in all cases the scent of snakes was discriminated from a blank control. We discuss the potential chemical mechanisms that may allow age recognition and its implications for social and sexual behavior of this snake species.

  19. Fear the serpent: A psychometric study of snake phobia.

    Science.gov (United States)

    Polák, Jakub; Sedláčková, Kristýna; Nácar, David; Landová, Eva; Frynta, Daniel

    2016-08-30

    Millions of people worldwide suffer from specific phobias. Almost any stimulus may trigger a phobic reaction, but snakes are among the most feared objects. Half of the population feel anxious about snakes and 2-3% meet the diagnostic criteria for snake phobia. Despite such a high ratio, only one instrument is commonly used, the Snake Questionnaire (SNAQ). The aim of this study was to develop a standardized Czech translation, describe its psychometric properties and analyze the distribution of snake fears. In a counter-balanced design 755 respondents were asked to complete the English and Czech SNAQ (first or last) with a 2-3 month delay; 300 of them completed both instruments. We found excellent test-retest reliability (0.94), although the total scores differed significantly when the English version was administered first. The mean score was 5.80 and Generalized Linear Models revealed significant effects of sex and field of study (women and people with no biology education scored higher than men and biologists). A cut-off point for snake phobia as derived from a previous study identified 2.6% of the subjects as phobic. Finally, the score distribution was similar to other countries supporting the view that fear of snakes is universal. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. Chemosensory age discrimination in the snake Boa constrictor (Serpentes: Boidae).

    Science.gov (United States)

    Gabirot, Marianne; Picerno, Pablo; Valencia, Jorge; Lopez, Pilar; Martin, José

    2012-12-01

    Many snakes are able to use their chemosensory system to detect scent of conspecifics, which is important in many social contexts. Age discrimination based on chemical cues may be especially important to ensure access to sexually mature potential partners. In this study, we used 24 individual Boa constrictor snakes (12 adults mature and 12 non-mature individuals) that had been captured in different areas of Ecuador, and were maintained in captivity at the Vivarium of Quito. We used tongue-flick experiments to examine whether these snakes were able to discriminate between scents from mature and non-mature individuals. Results showed that B. constrictor snakes used chemical cues to recognize conspecifics and that the scent of individuals of different ages elicited chemosensory responses of different magnitudes. The scents from adult conspecifics elicited the quickest and highest chemosensory responses (i.e., short latency times and high tongue-flick rates), although we did not find differential responses to scent of males and females. The magnitude of the responses was lower to scent of sub adult individuals, and then even lower to scent of juvenile snakes, but in all cases the scent of snakes was discriminated from a blank control. We discuss the potential chemical mechanisms that may allow age recognition and its implications for social and sexual behavior of this snake species.

  1. Visual system evolution and the nature of the ancestral snake.

    Science.gov (United States)

    Simões, B F; Sampaio, F L; Jared, C; Antoniazzi, M M; Loew, E R; Bowmaker, J K; Rodriguez, A; Hart, N S; Hunt, D M; Partridge, J C; Gower, D J

    2015-07-01

    The dominant hypothesis for the evolutionary origin of snakes from 'lizards' (non-snake squamates) is that stem snakes acquired many snake features while passing through a profound burrowing (fossorial) phase. To investigate this, we examined the visual pigments and their encoding opsin genes in a range of squamate reptiles, focusing on fossorial lizards and snakes. We sequenced opsin transcripts isolated from retinal cDNA and used microspectrophotometry to measure directly the spectral absorbance of the photoreceptor visual pigments in a subset of samples. In snakes, but not lizards, dedicated fossoriality (as in Scolecophidia and the alethinophidian Anilius scytale) corresponds with loss of all visual opsins other than RH1 (λmax 490-497 nm); all other snakes (including less dedicated burrowers) also have functional sws1 and lws opsin genes. In contrast, the retinas of all lizards sampled, even highly fossorial amphisbaenians with reduced eyes, express functional lws, sws1, sws2 and rh1 genes, and most also express rh2 (i.e. they express all five of the visual opsin genes present in the ancestral vertebrate). Our evidence of visual pigment complements suggests that the visual system of stem snakes was partly reduced, with two (RH2 and SWS2) of the ancestral vertebrate visual pigments being eliminated, but that this did not extend to the extreme additional loss of SWS1 and LWS that subsequently occurred (probably independently) in highly fossorial extant scolecophidians and A. scytale. We therefore consider it unlikely that the ancestral snake was as fossorial as extant scolecophidians, whether or not the latter are para- or monophyletic. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

  2. Pentastomids of wild snakes in the Australian tropics☆

    Science.gov (United States)

    Kelehear, Crystal; Spratt, David M.; O’Meally, Denis; Shine, Richard

    2013-01-01

    Pentastomids are endoparasites of the respiratory system of vertebrates, maturing primarily in carnivorous reptiles. Adult and larval pentastomids can cause severe pathology resulting in the death of their intermediate and definitive hosts. The study of pentastomids is a neglected field, impaired by risk of zoonoses, difficulties in species identification, and life cycle complexities. We surveyed wild snakes in the tropics of Australia to clarify which host species possess these parasites, and then sought to identify these pentastomids using a combination of morphological and molecular techniques. We detected pentastomid infections in 59% of the 81 snakes surveyed. The ubiquity of pentastomid infections in snakes of the Australian tropics sampled in this study is alarmingly high considering the often-adverse consequences of infection and the recognized zoonotic potential of these parasites. The pentastomids were of the genera Raillietiella and Waddycephalus and infected a range of host taxa, encompassing seven snake species from three snake families. All seven snake species represent new host records for pentastomids of the genera Raillietiella and/or Waddycephalus. The arboreal colubrid Dendrelaphis punctulatus and the terrestrial elapid Demansia vestigiata had particularly high infection prevalences (79% and 100% infected, respectively). Raillietiella orientalis infected 38% of the snakes surveyed, especially frog-eating species, implying a frog intermediate host for this parasite. Raillietiella orientalis was previously known only from Asian snakes and has invaded Australia via an unknown pathway. Our molecular data indicated that five species of Waddycephalus infect 28% of snakes in the surveyed area. Our morphological data indicate that features of pentastomid anatomy previously utilised to identify species of the genus Waddycephalus are unreliable for distinguishing species, highlighting the need for additional taxonomic work on this genus. PMID:24918074

  3. Pentastomids of wild snakes in the Australian tropics.

    Science.gov (United States)

    Kelehear, Crystal; Spratt, David M; O'Meally, Denis; Shine, Richard

    2014-04-01

    Pentastomids are endoparasites of the respiratory system of vertebrates, maturing primarily in carnivorous reptiles. Adult and larval pentastomids can cause severe pathology resulting in the death of their intermediate and definitive hosts. The study of pentastomids is a neglected field, impaired by risk of zoonoses, difficulties in species identification, and life cycle complexities. We surveyed wild snakes in the tropics of Australia to clarify which host species possess these parasites, and then sought to identify these pentastomids using a combination of morphological and molecular techniques. We detected pentastomid infections in 59% of the 81 snakes surveyed. The ubiquity of pentastomid infections in snakes of the Australian tropics sampled in this study is alarmingly high considering the often-adverse consequences of infection and the recognized zoonotic potential of these parasites. The pentastomids were of the genera Raillietiella and Waddycephalus and infected a range of host taxa, encompassing seven snake species from three snake families. All seven snake species represent new host records for pentastomids of the genera Raillietiella and/or Waddycephalus. The arboreal colubrid Dendrelaphis punctulatus and the terrestrial elapid Demansia vestigiata had particularly high infection prevalences (79% and 100% infected, respectively). Raillietiella orientalis infected 38% of the snakes surveyed, especially frog-eating species, implying a frog intermediate host for this parasite. Raillietiella orientalis was previously known only from Asian snakes and has invaded Australia via an unknown pathway. Our molecular data indicated that five species of Waddycephalus infect 28% of snakes in the surveyed area. Our morphological data indicate that features of pentastomid anatomy previously utilised to identify species of the genus Waddycephalus are unreliable for distinguishing species, highlighting the need for additional taxonomic work on this genus.

  4. Comparison of sea snake (Hydrophiidae) neurotoxin to cobra (Naja) neurotoxin.

    Science.gov (United States)

    Komori, Yumiko; Nagamizu, Masaya; Uchiya, Kei-Ichi; Nikai, Toshiaki; Tu, Anthony T

    2009-12-01

    Both sea snakes and cobras have venoms containing postsynaptic neurotoxins. Comparison of the primary structures indicates many similarities, especially the positions of the four disulfide bonds. However, detailed examination reveals differences in several amino acid residues. Amino acid sequences of sea snake neurotoxins were determined, and then compared to cobra neurotoxins by computer modeling. This allowed for easy comparison of the similarities and differences between the two types of postsynaptic neurotoxins. Comparison of computer models for the toxins of sea snakes and cobra will reveal the three dimensional difference of the toxins much clearer than the amino acid sequence alone.

  5. Non-venomous snake bite and snake bite without envenoming in a Brazilian teaching hospital. Analysis of 91 cases.

    Science.gov (United States)

    Silveria, P V; Nishioka, S de A

    1992-01-01

    A retrospective survey of 473 cases of snake bite admitted to a Brazilian teaching hospital from 1984 to 1990 revealed 91 cases of bite without envenoming and/or caused by non-venomous snakes. In 17 of these cases the snake was identified, and one patient was bitten by a snake-like reptile (Amphisbaena mertensii). In 43 cases diagnosis was made on clinical grounds (fang marks in the absence of signs of envenoming). The other 30 cases were of patients who complained of being bitten but who did not show any sign of envenoming or fang mark. Most cases occurred in men (66;73%), in the 10-19 years age group (26;29%), in the lower limbs (51/74;69%), between 6 A. M. and 2 P.M. (49;61%) and in the month of April (16;18%). One patient bitten by Philodryas olfersii developed severe local pain, swelling and redness at the site of the bite, with normal clotting time. The patient bitten by Drymarcon corais was misdiagnosed as being bitten by a snake of the genus Bothrops, was given the specific antivenom, and developed anaphylaxis. One patient bitten by Sibynomorphus mikanii presented prolonged clotting time, and was also given antivenom as a case of Bothrops bite. Correct identification of venomous snakes by physicians is necessary to provide correct treatment to victims of snake bite, avoiding unnecessary distress to the patient, and overprescription of antivenom, which may eventually cause severe untoward effects.

  6. Expression pattern of three-finger toxin and phospholipase A2 genes in the venom glands of two sea snakes, Lapemis curtus and Acalyptophis peronii: comparison of evolution of these toxins in land snakes, sea kraits and sea snakes

    Science.gov (United States)

    Pahari, Susanta; Bickford, David; Fry, Bryan G; Kini, R Manjunatha

    2007-01-01

    Background Snake venom composition varies widely both among closely related species and within the same species, based on ecological variables. In terrestrial snakes, such variation has been proposed to be due to snakes' diet. Land snakes target various prey species including insects (arthropods), lizards (reptiles), frogs and toads (amphibians), birds (aves), and rodents (mammals), whereas sea snakes target a single vertebrate class (fishes) and often specialize on specific types of fish. It is therefore interesting to examine the evolution of toxins in sea snake venoms compared to that of land snakes. Results Here we describe the expression of toxin genes in the venom glands of two sea snakes, Lapemis curtus (Spine-bellied Sea Snake) and Acalyptophis peronii (Horned Sea Snake), two members of a large adaptive radiation which occupy very different ecological niches. We constructed cDNA libraries from their venom glands and sequenced 214 and 192 clones, respectively. Our data show that despite their explosive evolutionary radiation, there is very little variability in the three-finger toxin (3FTx) as well as the phospholipase A2 (PLA2) enzymes, the two main constituents of Lapemis curtus and Acalyptophis peronii venom. To understand the evolutionary trends among land snakes, sea snakes and sea kraits, pairwise genetic distances (intraspecific and interspecific) of 3FTx and PLA2 sequences were calculated. Results show that these proteins appear to be highly conserved in sea snakes in contrast to land snakes or sea kraits, despite their extremely divergent and adaptive ecological radiation. Conclusion Based on these results, we suggest that streamlining in habitat and diet in sea snakes has possibly kept their toxin genes conserved, suggesting the idea that prey composition and diet breadth may contribute to the diversity and evolution of venom components. PMID:17900344

  7. Testing the Snake-Detection hypothesis : Larger early posterior negativity in humans to pictures of snakes than to pictures of other reptiles, spiders and slugs

    NARCIS (Netherlands)

    van Strien, Jan W.; Franken, Ingmar H A; Huijding, Jorg

    2014-01-01

    According to the snake detection hypothesis (Isbell, 2006), fear specifically of snakes may have pushed evolutionary changes in the primate visual system allowing pre-attentional visual detection of fearful stimuli. A previous study demonstrated that snake pictures, when compared to spiders or bird

  8. Detection of Chlamydia pneumoniae in a collection of captive snakes and response to treatment with marbofloxacin.

    Science.gov (United States)

    Rüegg, S R; Regenscheit, N; Origgi, F C; Kaiser, C; Borel, N

    2015-09-01

    In a collection of 58 snakes comprising predominantly Eurasian vipers in Switzerland, five snakes died unexpectedly during hibernation from 2009 to 2012. In one snake, organisms resembling chlamydiae were detected by immunohistochemistry in multiple histiocytic granulomas. Real-time quantitative PCR and microarray analysis were used to determine the presence of Chlamydia pneumoniae in tissue samples and cloacal/choanal swabs from snakes in the collection; 8/53 (15.1%) of the remaining snakes were positive. Although one infected snake had suppurative periglossitis, infection with C. pneumoniae did not appear to be associated with specific clinical signs in snakes. Of seven snakes treated with 5 mg/kg marbofloxacin IM once daily, five became PCR negative for C. pneumoniae following treatment, whereas one animal remained positive and one snake was lost to follow-up. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Molecular Evolution of the Infrared Sensory Gene TRPA1 in Snakes and Implications for Functional Studies

    Science.gov (United States)

    Jiang, Ke; Zhang, Peng

    2011-01-01

    TRPA1 is a calcium ion channel protein recently identified as the infrared receptor in pit organ-containing snakes. Therefore, understanding the molecular evolution of TRPA1 may help to illuminate the origin of “heat vision” in snakes and reveal the molecular mechanism of infrared sensitivity for TRPA1. To this end, we sequenced the infrared sensory gene TRPA1 in 24 snake species, representing nine snake families and multiple non-snake outgroups. We found that TRPA1 is under strong positive selection in the pit-bearing snakes studied, but not in other non-pit snakes and non-snake vertebrates. As a comparison, TRPV1, a gene closely related to TRPA1, was found to be under strong purifying selection in all the species studied, with no difference in the strength of selection between pit-bearing snakes and non-pit snakes. This finding demonstrates that the adaptive evolution of TRPA1 specifically occurred within the pit-bearing snakes and may be related to the functional modification for detecting infrared radiation. In addition, by comparing the TRPA1 protein sequences, we identified 11 amino acid sites that were diverged in pit-bearing snakes but conserved in non-pit snakes and other vertebrates, 21 sites that were diverged only within pit-vipers but conserved in the remaining snakes. These specific amino acid substitutions may be potentially functional important for infrared sensing. PMID:22163322

  10. The origin of snakes: revealing the ecology, behavior, and evolutionary history of early snakes using genomics, phenomics, and the fossil record.

    Science.gov (United States)

    Hsiang, Allison Y; Field, Daniel J; Webster, Timothy H; Behlke, Adam D B; Davis, Matthew B; Racicot, Rachel A; Gauthier, Jacques A

    2015-05-20

    The highly derived morphology and astounding diversity of snakes has long inspired debate regarding the ecological and evolutionary origin of both the snake total-group (Pan-Serpentes) and crown snakes (Serpentes). Although speculation abounds on the ecology, behavior, and provenance of the earliest snakes, a rigorous, clade-wide analysis of snake origins has yet to be attempted, in part due to a dearth of adequate paleontological data on early stem snakes. Here, we present the first comprehensive analytical reconstruction of the ancestor of crown snakes and the ancestor of the snake total-group, as inferred using multiple methods of ancestral state reconstruction. We use a combined-data approach that includes new information from the fossil record on extinct crown snakes, new data on the anatomy of the stem snakes Najash rionegrina, Dinilysia patagonica, and Coniophis precedens, and a deeper understanding of the distribution of phenotypic apomorphies among the major clades of fossil and Recent snakes. Additionally, we infer time-calibrated phylogenies using both new 'tip-dating' and traditional node-based approaches, providing new insights on temporal patterns in the early evolutionary history of snakes. Comprehensive ancestral state reconstructions reveal that both the ancestor of crown snakes and the ancestor of total-group snakes were nocturnal, widely foraging, non-constricting stealth hunters. They likely consumed soft-bodied vertebrate and invertebrate prey that was subequal to head size, and occupied terrestrial settings in warm, well-watered, and well-vegetated environments. The snake total-group - approximated by the Coniophis node - is inferred to have originated on land during the middle Early Cretaceous (~128.5 Ma), with the crown-group following about 20 million years later, during the Albian stage. Our inferred divergence dates provide strong evidence for a major radiation of henophidian snake diversity in the wake of the Cretaceous-Paleogene (K

  11. Broodyear data - Snake River sockeye salmon captive propagation

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gene rescue captive broodstock program was established for ESA-listed endangered Snake River sockeye salmon from Redfish Lake, Idaho. The program has consisted of...

  12. Growth data - Snake River sockeye salmon captive propagation

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gene rescue captive broodstock program was established for ESA-listed endangered Snake River sockeye salmon from Redfish Lake, Idaho. The program has consisted of...

  13. Production data - Snake River sockeye salmon captive propagation

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gene rescue captive broodstock program was established for ESA-listed endangered Snake River sockeye salmon from Redfish Lake, Idaho. The program has consisted of...

  14. Snake Creek National Wildlife Refuge [Narrative report: September - December 1956

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This narrative report for Snake Creek National Wildlife Refuge outlines Refuge accomplishments from September through December of 1956. The report begins by...

  15. MODELING SNAKE MICROHABITAT FROM RADIOTELEMETRY STUDIES USING POLYTOMOUS LOGISTIC REGRESSION

    Science.gov (United States)

    Multivariate analysis of snake microhabitat has historically used techniques that were derived under assumptions of normality and common covariance structure (e.g., discriminant function analysis, MANOVA). In this study, polytomous logistic regression (PLR which does not require ...

  16. Spawning data - Snake River sockeye salmon captive propagation

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gene rescue captive broodstock program was established for ESA-listed endangered Snake River sockeye salmon from Redfish Lake, Idaho. The program has consisted of...

  17. Fish Culture data - Snake River sockeye salmon captive propagation

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gene rescue captive broodstock program was established for ESA-listed endangered Snake River sockeye salmon from Redfish Lake, Idaho. The program has consisted of...

  18. Spectacular manifestations of systemic diseases of the snake

    DEFF Research Database (Denmark)

    Da Silva, Mari-Ann Otkjær; Bertelsen, Mads Frost; Heegaard, Steffen

    2015-01-01

    This paper reports histopathological findings in the spectacles of four snakes diagnosed with systemic gout, inclusion body disease, disseminated lymphoma and myeloproliferative disease, respectively. Gout was characterised by urate ghost tophi in the stroma and outer epithelium of the spectacle...

  19. Locomotion Efficiency Optimization of Biologically Inspired Snake Robots

    Directory of Open Access Journals (Sweden)

    Eleni Kelasidi

    2018-01-01

    Full Text Available Snake robots constitute bio-inspired solutions that have been studied due to their ability to move in challenging environments where other types of robots, such as wheeled or legged robots, usually fail. In this paper, we consider both land-based and swimming snake robots. One of the principal concerns of the bio-inspired snake robots is to increase the motion efficiency in terms of the forward speed by improving the locomotion methods. Furthermore, energy efficiency becomes a crucial challenge for this type of robots due to the importance of long-term autonomy of these systems. In this paper, we take into account both the minimization of the power consumption and the maximization of the achieved forward velocity in order to investigate the optimal gait parameters for bio-inspired snake robots using lateral undulation and eel-like motion patterns. We furthermore consider possible negative work effects in the calculation of average power consumption of underwater snake robots. To solve the multi-objective optimization problem, we propose transforming the two objective functions into a single one using a weighted-sum method. For different set of weight factors, Particle Swarm Optimization is applied and a set of optimal points is consequently obtained. Pareto fronts or trade-off curves are illustrated for both land-based and swimming snake robots with different numbers of links. Pareto fronts represent trade-offs between the objective functions. For example, how increasing the forward velocity results in increasing power consumption. Therefore, these curves are a very useful tool for the control and design of snake robots. The trade-off curve thus constitutes a very useful tool for both the control and design of bio-inspired snake robots. In particular, the operators or designers of bio-inspired snake robots can choose a Pareto optimal point based on the trade-off curve, given the preferred number of links on the robot. The optimal gait parameters

  20. An airborne sex pheromone in snakes

    Science.gov (United States)

    Shine, R.; Mason, R. T.

    2012-01-01

    Most reptile sex pheromones so far described are lipid molecules too large to diffuse through the air; instead, they are detected via direct contact (tongue-flicking) with another animal's body or substrate-deposited trails, using the vomeronasal system. The only non-lipid pheromone reported in snakes involves courtship termination in red-sided gartersnakes (Thamnophis sirtalis parietalis): males that encounter copulatory fluids cease courtship, presumably reflecting the futility of courting an already-mating female. Our field experiments at a communal den in Manitoba show that this pheromone can work via olfaction: courtship is terminated by exposure to airborne scents from mating conspecifics, and does not require direct contact (tongue-flicking). Hence, the sexual behaviour of reptiles can be affected by airborne as well as substrate-bound pheromones. PMID:21992822

  1. Afibrinogenemia following snake bite (Crotalus durissus terrificus

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    C. F. S. Amaral

    1988-08-01

    Full Text Available This paper reports two cases of afibrinogenemia with normal platelet count following Crotalus durissus terrificus, snake bite Both patients presented high output acute renal failure and case two also had increased blood levels of CPK and LDH compatible with the diagnosis of rhabdomyolysis. Case one was given an unknown amount of antivenom and was treated with epsilonaminocaproic acid and a fresh whole blood transfusion and showed recovery of the coagulation disturbance 40 hours following these measures. Case two was given an adequate amount of crotalide antivenom and the coagulation tests performed 12 hours later showed a normal partial thromboplastin time and fibrinogen 86 mg/100ml. Case one presented no haemorrhagic disturbances. Case two presented persistent bleeding following venopuncture and after removal of impetigo crust in the legs. Acute renal failure was treated conservatively and both patients were discharged from the hospital with recovery of the renal function.

  2. Crystal structure of a snake venom cardiotoxin

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    Rees, B.; Samama, J.P.; Thierry, J.C.; Gilibert, M.; Fischer, J.; Schweitz, H.; Lazdunski, M.; Moras, D.

    1987-05-01

    Cardiotoxin V/sup II/4 from Naja mossambica crystallizes in space group P6/sub 1/ (a = b = 73.9 A; c = 59.0 A) with two molecules of toxin (molecular mass = 6715 Da) in the asymmetric unit. The structure was solved by using a combination of multiple isomorphous replacement and density modification methods. Model building and least-squares refinement led to an agreement factor of 27% for a data set to 3-A resolution prior to any inclusion of solvent molecules. The topology of the molecule is similar to that found in short and long snake neurotoxins, which block the nicotinic acetylcholine receptor. Major differences occur in the conformation of the central loop, resulting in a change in the concavity of the molecule. Hydrophobic residues are clustered in two distinct areas. The existence of stable dimeric entities in the crystalline state, with the formation of a six-stranded antiparallel ..beta.. sheet, may be functionally relevant.

  3. Factors underlying the natural resistance of animals against snake venoms

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    H. Moussatché

    1989-01-01

    Full Text Available The existence of mammals and reptilia with a natural resistance to snake venoms is known since a long time. This fact has been subjected to the study by several research workers. Our experiments showed us that in the marsupial Didelphis marsupialis, a mammal highly resistant to the venom of Bothrops jararaca, and other Bothrops venoms, has a genetically origin protein, a alpha-1, acid glycoprotein, now highly purified, with protective action in mice against the jararaca snake venom.

  4. Backward Masked Snakes and Guns Modulate Spatial Attention

    OpenAIRE

    Joshua M. Carlson; Andrea L. Fee; Reinke, Karen S.

    2009-01-01

    Fearful faces are important social cues that alert others of potential threat. Even backward masked fearful faces facilitate spatial attention. However, visual stimuli other than fearful faces can signal potential threat. Indeed, unmasked snakes and spiders modulate spatial attention. Yet, it is unclear if the rapid threat-related facilitation of spatial attention to backward masked stimuli is elicited by non-face threat cues. Evolutionary theories claim that phylogenetic threats (i.e. snakes...

  5. The venomous coral snakes (genus Micrurus) of Costa Rica

    OpenAIRE

    Savage, Jay M.; Vial, James L.

    2016-01-01

    Four species of venomous coral snakes (Micrurus) occur in Costa Rica. The single bicolor species, M. mipartitus has previously been defined as two subspecies; however, variations in diagnostic characters clemonstrate dinal shift that precludes recognition of geographic races.Presence of the tricolor M. clarki is concluded from but a single Costa Rican specimen, although the species is otherwise definitely known from adjacent areas in Panamá.Variation among tricolor coral snakes allied to M. n...

  6. Chemosensory age discrimination in the snake Boa constrictor (Serpentes: Boidae)

    OpenAIRE

    Marianne Gabirot; Pablo Picerno; Jorge Valencia; Pilar Lopez; José Martin

    2012-01-01

    Many snakes are able to use their chemosensory system to detect scent of conspecifics, which is important in many social contexts. Age discrimination based on chemical cues may be especially important to ensure access to sexually mature potential partners. In this study, we used 24 individual Boa constrictor snakes (12 adults mature and 12 non-mature individuals) that had been captured in different areas of Ecuador, and were maintained in captivity at the Vivarium of Quito. We used tongue-fli...

  7. Overcoming an intrinsic depolarizing resonance with a partial Siberian snake

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    H. Huang

    2004-07-01

    Full Text Available An 11.4% partial Siberian snake was used to successfully accelerate polarized protons through a strong intrinsic depolarizing spin resonance in the Alternating Gradient Synchrotron (AGS. No noticeable depolarization was observed. This opens up the possibility of using a 20% to 30% partial Siberian snake in the AGS or other medium energy proton synchrotrons to overcome all weak and strong depolarizing spin resonances.

  8. Oxygenation properties and isoform diversity of snake hemoglobins.

    Science.gov (United States)

    Storz, Jay F; Natarajan, Chandrasekhar; Moriyama, Hideaki; Hoffmann, Federico G; Wang, Tobias; Fago, Angela; Malte, Hans; Overgaard, Johannes; Weber, Roy E

    2015-11-01

    Available data suggest that snake hemoglobins (Hbs) are characterized by a combination of unusual structural and functional properties relative to the Hbs of other amniote vertebrates, including oxygenation-linked tetramer-dimer dissociation. However, standardized comparative data are lacking for snake Hbs, and the Hb isoform composition of snake red blood cells has not been systematically characterized. Here we present the results of an integrated analysis of snake Hbs and the underlying α- and β-type globin genes to characterize 1) Hb isoform composition of definitive erythrocytes, and 2) the oxygenation properties of isolated isoforms as well as composite hemolysates. We used species from three families as subjects for experimental studies of Hb function: South American rattlesnake, Crotalus durissus (Viperidae); Indian python, Python molurus (Pythonidae); and yellow-bellied sea snake, Pelamis platura (Elapidae). We analyzed allosteric properties of snake Hbs in terms of the Monod-Wyman-Changeux model and Adair four-step thermodynamic model. Hbs from each of the three species exhibited high intrinsic O2 affinities, low cooperativities, small Bohr factors in the absence of phosphates, and high sensitivities to ATP. Oxygenation properties of the snake Hbs could be explained entirely by allosteric transitions in the quaternary structure of intact tetramers, suggesting that ligation-dependent dissociation of Hb tetramers into αβ-dimers is not a universal feature of snake Hbs. Surprisingly, the major Hb isoform of the South American rattlesnake is homologous to the minor HbD of other amniotes and, contrary to the pattern of Hb isoform differentiation in birds and turtles, exhibits a lower O2 affinity than the HbA isoform. Copyright © 2015 the American Physiological Society.

  9. CORAL SNAKE ANTIVENOM PRODUCED IN CHICKENS (Gallus domesticus)

    OpenAIRE

    Irma Aguilar; Elda E. Sanchez; Maria E. Giron; Amalid Estrella; Belsy Guerrero; F. Alexis Rodriguez-Acosta

    2014-01-01

    The production of anti-snake venom from large mammal's blood has been found to be low-yielding and arduous, consequently, antivenom immunoglobulins for treatment are achieved regularly as polyvalent serum. We have standardized an undemanding technique for making purified immunoglobulin IgY antivenom consisting of polyclonal antibodies against coral snake venom in the egg yolk of immunized hens. We have adapted a reported process of antibody purification from egg yolks, and achieved 90% antibo...

  10. Ecological and phylogenetic influences on maxillary dentition in snakes

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    Kate Jackson

    2010-12-01

    Full Text Available The maxillary dentition of snakes was used as a system with which to investigate the relative importance of the interacting forces of ecological selective pressures and phylogenetic constraints indetermining morphology. The maxillary morphology of three groups of snakes having different diets, with each group comprising two distinct lineages — boids and colubroids — was examined. Our results suggest that dietary selective pressures may be more significantthan phylogenetic history in shaping maxillary morphology.

  11. Venom yields from Australian and some other species of snakes.

    Science.gov (United States)

    Mirtschin, Peter J; Dunstan, Nathan; Hough, Ben; Hamilton, Ewan; Klein, Sharna; Lucas, Jonathan; Millar, David; Madaras, Frank; Nias, Timothy

    2006-08-01

    The wet and dry venom yields for most Australian native dangerous snakes and a number of non-Australian species are presented. Snakes from the Pseudonaja genus yielded higher than previously published amounts and suggest reconsideration be given to increasing the volume of antivenom in each vial. Higher percentage solids were obtained from venoms from the 4 cobra species (Naja) and Pseudechis genus included in this series.

  12. [Clinical aspects and treatment of bites by poisonous snakes].

    Science.gov (United States)

    Van den Enden, E J; Van Gompel, A; Wijnants, H; Colebunders, R; Van den Ende, J

    1991-01-01

    Every year there are hundreds of snake bites in Europe, but the main problems occur in tropical areas. Symptoms such as hemorrhages, paralysis and local necrosis vary according to the snake species. Inappropriate first aid should be avoided. Antitoxin should be administered if there are signs of poisoning. It is never too late to give antitoxin. Antitoxin can have a number of potentially very dangerous side-effects.

  13. Diadophis Puntatus Puntatus (Southern Ring-neck Snake) Predation

    Science.gov (United States)

    Gotte, Steve W.

    2016-01-01

    DIADOPHIS PUNCTATUS PUNCTATUS (Southern Ring-necked Snake). PREDATION. Here I present the first record of Buteo lineatus (Red-shouldered Hawk) predator on a Diadophis p. punctatus. At ca. 1100h on l2 February2 013,I observed a B. lineatus eating a katydid in Corkscrew Swamp Sanctuary (26.2730'N, 81.6079"W;WGS 84), Collier Co., Florida, USA. The hawk was in a Pond Cypress tree on the edge of a small prairie bordered on one side by a cypress swamp and by pine woodland on the other. Immediately upon consuming the katydid, the hawk flew to the ground ca. 1.5 m from an elevated boardwalk to grab an adult D. punctatus. It then flew with the snake in its talons to a branch 3 m high ca. l0 m from the boardwalk. The hawk stretched and otherwise manipulated the struggling snake (Fig.1) before consuming the still moving snake. Although snakes are a well-known component of B. lineatus diet (Clark1 987A. Field Guide to the Hawks of North America. Houghton Mifflin Co. Boston, Massachusetts 198 pp.), I found only one literature reference to Red-shouldered Hawks eating Ring-neck Snakes (Fisher 1893.Hawks and Owls of the United States in their Relation to Agriculture. U.S. Dept. Agric., Div Ornith. Mamm. Bull. 3). That specimen was from Canton, New York (taken 26 Oct IBBB) and would be a D. p. edwardisii (Northern Ring-necked Snake), while the snake reported on here is a Diadophis p. punctatus (USNM Herp Image 2847a -c). Based on evidence presented by Fontanella et al. (2008. Mol. Phylogenet Evol.46:1049-1070), D. p. edwardisii and D. p. punctatus are likely different species.

  14. Mechanisms of virus resistance and antiviral activity of snake venoms

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    JVR Rivero

    2011-01-01

    Full Text Available Viruses depend on cell metabolism for their own propagation. The need to foster an intimate relationship with the host has resulted in the development of various strategies designed to help virus escape from the defense mechanisms present in the host. Over millions of years, the unremitting battle between pathogens and their hosts has led to changes in evolution of the immune system. Snake venoms are biological resources that have antiviral activity, hence substances of significant pharmacological value. The biodiversity in Brazil with respect to snakes is one of the richest on the planet; nevertheless, studies on the antiviral activity of venom from Brazilian snakes are scarce. The antiviral properties of snake venom appear as new promising therapeutic alternative against the defense mechanisms developed by viruses. In the current study, scientific papers published in recent years on the antiviral activity of venom from various species of snakes were reviewed. The objective of this review is to discuss the mechanisms of resistance developed by viruses and the components of snake venoms that present antiviral activity, particularly, enzymes, amino acids, peptides and proteins.

  15. Snake Venom: From Deadly Toxins to Life-saving Therapeutics.

    Science.gov (United States)

    Waheed, Humera; Moin, Syed F; Choudhary, M I

    2017-01-01

    Snakes are fascinating creatures and have been residents of this planet well before ancient humans dwelled the earth. Venomous snakes have been a figure of fear, and cause notable mortality throughout the world. The venom constitutes families of proteins and peptides with various isoforms that make it a cocktail of diverse molecules. These biomolecules are responsible for the disturbance in fundamental physiological systems of the envenomed victim, leading to morbidity which can lead to death if left untreated. Researchers have turned these life-threatening toxins into life-saving therapeutics via technological advancements. Since the development of captopril, the first drug that was derived from bradykininpotentiating peptide of Bothrops jararaca, to the disintegrins that have potent activity against certain types of cancers, snake venom components have shown great potential for the development of lead compounds for new drugs. There is a continuous development of new drugs from snake venom for coagulopathy and hemostasis to anti-cancer agents. In this review, we have focused on different snake venom proteins / peptides derived drugs that are in clinical use or in developmental stages till to date. Also, some commonly used snake venom derived diagnostic tools along with the recent updates in this exciting field are discussed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  16. A Review and Database of Snake Venom Proteomes

    Science.gov (United States)

    Tasoulis, Theo

    2017-01-01

    Advances in the last decade combining transcriptomics with established proteomics methods have made possible rapid identification and quantification of protein families in snake venoms. Although over 100 studies have been published, the value of this information is increased when it is collated, allowing rapid assimilation and evaluation of evolutionary trends, geographical variation, and possible medical implications. This review brings together all compositional studies of snake venom proteomes published in the last decade. Compositional studies were identified for 132 snake species: 42 from 360 (12%) Elapidae (elapids), 20 from 101 (20%) Viperinae (true vipers), 65 from 239 (27%) Crotalinae (pit vipers), and five species of non-front-fanged snakes. Approximately 90% of their total venom composition consisted of eight protein families for elapids, 11 protein families for viperines and ten protein families for crotalines. There were four dominant protein families: phospholipase A2s (the most common across all front-fanged snakes), metalloproteases, serine proteases and three-finger toxins. There were six secondary protein families: cysteine-rich secretory proteins, l-amino acid oxidases, kunitz peptides, C-type lectins/snaclecs, disintegrins and natriuretic peptides. Elapid venoms contained mostly three-finger toxins and phospholipase A2s and viper venoms metalloproteases, phospholipase A2s and serine proteases. Although 63 protein families were identified, more than half were present in snake species studied and always in low abundance. The importance of these minor component proteins remains unknown. PMID:28927001

  17. Nestedness of snake assemblages on islands of an inundated lake

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    Yanping WANG, Xi WANG, Ping DING

    2012-06-01

    Full Text Available Nestedness is a pattern frequently reported for faunal assemblages in fragmented systems. Although nestedness has been documented for a wide range of taxa, it is rarely tested in snake assemblages. To arrive at robust generalizations about proce­sses and mechanisms structuring island biotas, it is important to examine under-represented taxa such as snakes for the insights they may offer. We tested for the existence of nestedness and underlying causal mechanisms using snake data collected on islands in the Thousand Island Lake, China. We used the line-transect method to survey snake occupancy and abundance on 20 islands during two breeding seasons in 2009 and 2010. We used the recently developed metric WNODF to estimate nestedness. We used Spearman rank correlations to examine the associations of nestedness and habitat variables (area, isolation, and habitat diversity as well as life-history traits (body size, clutch size, geographical range size and area requirement related to species extinction and immigration tendencies. Snake assemblages were significantly nested and were shaped by extinction processes mediated through area effects and habitat nestedness. The nestedness of snake assemblages was not due to passive sampling or selective colonization. From a conservation viewpoint, our results indicate that we should protect both the largest island with the most species-rich community and habitat-rich islands to maximize the number of species preserved [Current Zoology 58 (6: 828–836, 2012].

  18. Snakes mimic earthworms: propulsion using rectilinear travelling waves

    Science.gov (United States)

    Marvi, Hamidreza; Bridges, Jacob; Hu, David L.

    2013-01-01

    In rectilinear locomotion, snakes propel themselves using unidirectional travelling waves of muscular contraction, in a style similar to earthworms. In this combined experimental and theoretical study, we film rectilinear locomotion of three species of snakes, including red-tailed boa constrictors, Dumeril's boas and Gaboon vipers. The kinematics of a snake's extension–contraction travelling wave are characterized by wave frequency, amplitude and speed. We find wave frequency increases with increasing body size, an opposite trend than that for legged animals. We predict body speed with 73–97% accuracy using a mathematical model of a one-dimensional n-linked crawler that uses friction as the dominant propulsive force. We apply our model to show snakes have optimal wave frequencies: higher values increase Froude number causing the snake to slip; smaller values decrease thrust and so body speed. Other choices of kinematic variables, such as wave amplitude, are suboptimal and appear to be limited by anatomical constraints. Our model also shows that local body lifting increases a snake's speed by 31 per cent, demonstrating that rectilinear locomotion benefits from vertical motion similar to walking. PMID:23635494

  19. Constrained snake vs. conventional snake for carotid ultrasound automated IMT measurements on multi-center data sets.

    Science.gov (United States)

    Molinari, Filippo; Meiburger, Kristen M; Saba, Luca; Acharya, U Rajendra; Ledda, Mario; Nicolaides, Andrew; Suri, Jasjit S

    2012-09-01

    Accurate intima-media thickness (IMT) measurement of the carotid artery from minimal plaque ultrasound images is a relevant clinical need, since IMT increase is related to the progression of atherosclerosis. In this paper, we describe a novel dual snake-based model for the high-performance carotid IMT measurement, called Carotid Measurement Using Dual Snakes (CMUDS). Snakes (which are deformable contours) adapt to the lumen-intima (LI) and media-adventitia (MA) interfaces, thus enabling the IMT computation as distance between the LI and MA snakes. However, traditional snakes might be unable to maintain a correct distance and in some spatial location along the artery, it might even collapse between them or diverge. The technical improvement of this work is the definition of a dual snake-based constrained system, which prevents the LI and MA snakes from collapsing or bleeding, thus optimizing the IMT estimation. The CMUDS system consists of two parametric models automatically initialized using the far adventitia border which we automatically traced by using a previously developed multi-resolution approach. The dual snakes evolve simultaneously and are constrained by the distances between them, ensuring the regularization of LI/MA topology. We benchmarked our automated CMUDS with the previous conventional semi-automated snake system called Carotid Measurement Using Single Snake (CMUSS). Two independent readers manually traced the LIMA boundaries of a multi-institutional, multi-ethnic, and multi-scanner database of 665 CCA longitudinal 2D images. We evaluated our system performance by comparing it with the gold standard as traced by clinical readers. CMUDS and CMUSS correctly processed 100% of the 665 images. Comparing the performance with respect to the two readers, our automatically measured IMT was on average very close to that of the two readers (IMT measurement biases for CMUSS was equal to -0.011±0.329mm and -0.045±0.317mm, respectively, while for CMUDS, it was

  20. Volume of eggs in the clutches of Grass snake Natrix natrix and Dice snake N. tessellata: error correction

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    Klenina Anastasiya Aleksandrovna

    2015-12-01

    Full Text Available The authors have made a mistake in calculating the volume of eggs in the clutches of snake family Natrix. In this article we correct the error. As a result, it was revealed, that the volume of eggs positively correlates with a female length and its mass, as well as with the quantity of eggs in the clutches. There is a positive correlation between the characteristics of newborn snakes (length and mass and the volume of eggs, from which they hatched.

  1. High helmintic infection of the European grass snake, Natrix natrix and the dice snake, Natrix tessellate (Serpentes: Colubridae) from Iran

    OpenAIRE

    Mohammad Reza Yossefi; Reza Nikzad; Mohammad Nikzad; Ali Mousapour; Shahab Ramazanpour; Mohammad Taghi Rahimi

    2014-01-01

    Objective: To determine the helminth parasites of Natrix natrix Linnaeus, 1758 (N. natrix) and Natrix tessellata Laurenti, 1768 (N. tessellate) in north of Iran. Methods: Eighteen snakes including nine N. natrix and nine N. tessellata from Mazandaran Province, north of Iran were collected and examined during March 2011 to October 2011 for helminth parasites. The collected specimens were fixed and preserved in 70% ethanol. Results: All of the examined snakes (100%) were infected...

  2. Molecular analysis of the diets of snakes: changes in prey exploitation during development of the rare smooth snake Coronella austriaca.

    Science.gov (United States)

    Brown, David S; Ebenezer, Katie L; Symondson, William O C

    2014-08-01

    Reptiles are declining in many parts of the world, mainly due to habitat loss and environmental change. A major factor in this is availability of suitable food. For many animals, dietary requirements shift during developmental stages and a habitat will only be suitable for conserving a species if it supports all stages. Conventional methods for establishing diet often rely on visual recognition of morphologically identifiable features of prey in faeces, regurgitation or stomach contents, which suffer from biases and poor resolution of taxa. DNA-based techniques facilitate noninvasive analysis of diet from faeces without these constraints. We tested the hypothesis that diet changes during growth stages of smooth snakes (Coronella austriaca), which have a highly restricted distribution in the UK but are widespread in continental Europe. Small numbers of the sympatric grass snake (Natrix natrix) were analysed for comparison. Faecal samples were collected from snakes and prey DNA analysed using PCR, targeting amphibians, reptiles, mammals and invertebrates. Over 85% of smooth snakes were found to have eaten reptiles and 28% had eaten mammals. Predation on mammals increased with age and was entirely absent among juveniles and subadults. Predation on reptiles did not change ontogenetically. Smooth snakes may, therefore, be restricted to areas of sufficiently high reptile densities to support young snakes. © 2013 John Wiley & Sons Ltd.

  3. Food or threat? Wild capuchin monkeys (Sapajus libidinosus) as both predators and prey of snakes.

    Science.gov (United States)

    Falótico, Tiago; Verderane, Michele P; Mendonça-Furtado, Olívia; Spagnoletti, Noemi; Ottoni, Eduardo B; Visalberghi, Elisabetta; Izar, Patrícia

    2017-09-16

    Snakes present a hazard to primates, both as active predators and by defensive envenomation. This risk might have been a selective pressure on the evolution of primate visual and cognitive systems, leading to several behavioral traits present in human and non-human primates, such as the ability to quickly learn to fear snakes. Primates seldom prey on snakes, and humans are one of the few primate species that do. We report here another case, the wild capuchin monkey (Sapajus libidinosus), which preys on snakes. We hypothesized that capuchin monkeys, due to their behavioral plasticity, and cognitive and visual skills, would be capable of discriminating dangerous and non-dangerous snakes and behave accordingly. We recorded the behavioral patterns exhibited toward snakes in two populations of S. libidinosus living 320 km apart in Piauí, Brazil. As expected, capuchins have a fear reaction to dangerous snakes (usually venomous or constricting snakes), presenting mobbing behavior toward them. In contrast, they hunt and consume non-dangerous snakes without presenting the fear response. Our findings support the tested hypothesis that S. libidinosus are capable of differentiating snakes by level of danger: on the one hand they protect themselves from dangerous snakes, on the other hand they take opportunities to prey on non-dangerous snakes. Since capuchins and humans are both predators and prey of snakes, further studies of this complex relationship may shed light on the evolution of these traits in the human lineage.

  4. Black Bear Reactions to Venomous and Non-venomous Snakes in Eastern North America

    Science.gov (United States)

    Rogers, Lynn L; Mansfield, Susan A; Hornby, Kathleen; Hornby, Stewart; Debruyn, Terry D; Mize, Malvin; Clark, Rulon; Burghardt, Gordon M

    2014-01-01

    Bears are often considered ecological equivalents of large primates, but the latter often respond with fear, avoidance, and alarm calls to snakes, both venomous and non-venomous, there is sparse information on how bears respond to snakes. We videotaped or directly observed natural encounters between black bears (Ursus americanus) and snakes. Inside the range of venomous snakes in Arkansas and West Virginia, adolescent and adult black bears reacted fearfully in seven of seven encounters upon becoming aware of venomous and non-venomous snakes; but in northern Michigan and Minnesota where venomous snakes have been absent for millennia, black bears showed little or no fear in four encounters with non-venomous snakes of three species. The possible roles of experience and evolution in bear reactions to snakes and vice versa are discussed. In all areas studied, black bears had difficulty to recognize non-moving snakes by smell or sight. Bears did not react until snakes moved in 11 of 12 encounters with non-moving timber rattlesnakes (Crotalus horridus) and four species of harmless snakes. However, in additional tests in this study, bears were repulsed by garter snakes that had excreted pungent anal exudates, which may help explain the absence of snakes, both venomous and harmless, in bear diets reported to date. PMID:25635152

  5. Gliding flight in Chrysopelea: turning a snake into a wing.

    Science.gov (United States)

    Socha, John J

    2011-12-01

    Although many cylindrical animals swim through water, flying snakes of the genus Chrysopelea are the only limbless animals that glide through air. Despite a lack of limbs, these snakes can actively launch by jumping, maintain a stable glide path without obvious control surfaces, maneuver, and safely land without injury. Jumping takeoffs employ vertically looped kinematics that seem to be different than any other behavior in limbless vertebrates, and their presence in a closely related genus suggests that gap-crossing may have been a behavioral precursor to the evolution of gliding in snakes. Change in shape of the body by dorsoventral flattening and high-amplitude aerial undulation comprise two key features of snakes' gliding behavior. As the snake becomes airborne, the body flattens sequentially from head to vent, forming a cross-sectional shape that is roughly triangular, with a flat surface and lateral "lips" that protrude ventrally on each side of the body; these may diminish toward the vent. This shape likely provides the snake with lift coefficients that peak at high angles of attack and gentle stall characteristics. A glide trajectory is initiated with the snake falling at a steep angle. As the snake rotates in the pitch axis, it forms a wide "S" shape and begins undulating in a complex three-dimensional pattern, with the body angled upward relative to the glide path. The head moves side-to-side, sending traveling waves posteriorly toward the tail, while the body (most prominently, the posterior end) oscillates in the vertical axis. These active movements while gliding are substantially different and more dynamic than those used by any other animal glider. As the snake gains forward speed, the glide path becomes less steep, reaching minimally recorded glide angles of 13°. In general, smaller snakes appear to be more proficient gliders. Chrysopelea paradisi can also maneuver and land either on the ground or on vegetation, but these locomotor behaviors have

  6. Postnatal ontogeny and the evolution of macrostomy in snakes

    Science.gov (United States)

    2016-01-01

    Macrostomy is the anatomical feature present in macrostomatan snakes that permits the ingestion of entire prey with high cross-sectional area. It depends on several anatomical traits in the skeleton and soft tissues, of which the elongation of gnathic complex and backward rotation of the quadrate represent crucial skeletal requirements. Here, the relevance of postnatal development of these skull structures and their relationship with macrohabitat and diet are explored. Contrary to the condition present in lizards and basal snakes that occupy underground macrohabitats, elements of the gnathic complex of most macrostomatan snakes that exploit surface macrohabitats display conspicuous elongation during postnatal growth, relative to the rest of the skull, as well as further backward rotation of the quadrate bone. Remarkably, several clades of small cryptozoic macrostomatans reverse these postnatal transformations and return to a diet based on prey with low cross-sectional area such as annelids, insects or elongated vertebrates, thus resembling the condition present in underground basal snakes. Dietary ontogenetic shift observed in most macrostomatan snakes is directly linked with this ontogenetic trajectory, indicating that this shift is acquired progressively as the gnathic complex elongates and the quadrate rotates backward during postnatal ontogeny. The numerous independent events of reversion in the gnathic complex and prey type choice observed in underground macrostomatans and the presence of skeletal requirements for macrostomy in extinct non-macrostomatan species reinforce the possibility that basal snakes represent underground survivors of clades that had the skeletal requirements for macrostomy. Taken together, the data presented here suggest that macrostomy has been shaped during multiple episodes of occupation of underground and surface macrohabitats throughout the evolution of snakes. PMID:28018652

  7. Ecological and phylogenetic variability in the spinalis muscle of snakes.

    Science.gov (United States)

    Tingle, J L; Gartner, G E A; Jayne, B C; Garland, T

    2017-11-01

    Understanding the origin and maintenance of functionally important subordinate traits is a major goal of evolutionary physiologists and ecomorphologists. Within the confines of a limbless body plan, snakes are diverse in terms of body size and ecology, but we know little about the functional traits that underlie this diversity. We used a phylogenetically diverse group of 131 snake species to examine associations between habitat use, sidewinding locomotion and constriction behaviour with the number of body vertebrae spanned by a single segment of the spinalis muscle, with total numbers of body vertebrae used as a covariate in statistical analyses. We compared models with combinations of these predictors to determine which best fit the data among all species and for the advanced snakes only (N = 114). We used both ordinary least-squares models and phylogenetic models in which the residuals were modelled as evolving by the Ornstein-Uhlenbeck process. Snakes with greater numbers of vertebrae tended to have spinalis muscles that spanned more vertebrae. Habitat effects dominated models for analyses of all species and advanced snakes only, with the spinalis length spanning more vertebrae in arboreal species and fewer vertebrae in aquatic and burrowing species. Sidewinding specialists had shorter muscle lengths than nonspecialists. The relationship between prey constriction and spinalis length was less clear. Differences among clades were also strong when considering all species, but not for advanced snakes alone. Overall, these results suggest that muscle morphology may have played a key role in the adaptive radiation of snakes. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  8. First recorded case of paramyxovirus infection introduced into a healthy snake collection in Croatia.

    Science.gov (United States)

    Prpic, Jelena; Keros, Tomislav; Balija, Maja Lang; Forcic, Dubravko; Jemersic, Lorena

    2017-04-08

    In the present study, we describe the first paramyxovirus infection in a snake collection in Croatia caused by an introduction of new snakes that were not previously tested and didn't show any signs of disease. In less than a month after introduction into a healthy colony, new snakes began to show respiratory symptoms (i.e. mouth opening, wheezing, etc.) and died within a month and a half after antibiotic therapy was applied. The same symptoms and a high mortality rate were then observed in in-contact snakes from other collections belonging to different snake families. Two entries of new snakes in different time periods were recorded and recognized as possible sources of infection. We stress the need for veterinary health control and monitoring of snakes prior to transportation as well as implementing obligatory quarantine measures to minimize the risk of infection among newly established snake groups.

  9. Species Profile: Eastern Indigo Snake (Drymarchon corals couperi) on Military Installations in the Southeastern United States

    National Research Council Canada - National Science Library

    Hallam, Charlotte

    1998-01-01

    The eastern indigo snake (Dtymarchon corais couperi) is an uncommon, large-bodied snake occurring in the southeastern United States, primarily in southern Alabama and Georgia and most of Florida. The U.S...

  10. Retrospective study of snake envenomation in 155 dogs from the Onderstepoort area of South Africa

    OpenAIRE

    R.G. Lobetti; K. Joubert

    2004-01-01

    A retrospective study was undertaken to evaluate the incidence, signalment, haematological and biochemical changes, therapy, and outcome of dogs presented to the Outpatients section of the Onderstepoort Veterinary Academic Hospital for confirmed snake envenomation. Three hundred and seventy-six records of dogs presented for snake envenomation from 1998 to 2002 were reviewed and 155 were selected on the basis of there being a positively identified snake. The 2 most commonly encountered snake e...

  11. Black Bear Reactions to Venomous and Non-venomous Snakes in Eastern North America

    OpenAIRE

    Rogers, Lynn L; Mansfield, Susan A; Hornby, Kathleen; Hornby, Stewart; Debruyn, Terry D; Mize, Malvin; Clark, Rulon; Burghardt, Gordon M

    2014-01-01

    Bears are often considered ecological equivalents of large primates, but the latter often respond with fear, avoidance, and alarm calls to snakes, both venomous and non-venomous, there is sparse information on how bears respond to snakes. We videotaped or directly observed natural encounters between black bears (Ursus americanus) and snakes. Inside the range of venomous snakes in Arkansas and West Virginia, adolescent and adult black bears reacted fearfully in seven of seven encounters upon b...

  12. Mechanical diffraction in a sand-specialist snake

    Science.gov (United States)

    Schiebel, Perrin E.; Rieser, Jennifer M.; Hubbard, Alex M.; Chen, Lillian; Goldman, Daniel I.

    Limbless locomotors such as snakes move by pressing the trunk against terrain heterogeneities. Our laboratory studies of the desert-dwelling Mojave Shovel-nosed snake (C. occipitalis, 40cm long, N=9) reveal that these animals use a stereotyped sinusoidal traveling wave of curvature. However, this snake also encounters rigid obstacles in its natural environment, and the tradeoff between using a cyclic, shape controlled gait versus one which changes shape in response to the terrain is not well understood. We challenged individuals to move across a model deformable substrate (carpet) through a row of 6.4 mm diameter force-sensitive pegs, a model of obstacles such as grass, oriented perpendicular to the direction of motion. Instead of forward-directed reaction forces, reaction forces generated by the pegs were more often perpendicular to the direction of motion. Distributions of post-peg travel angles displayed preferred directions revealing a diffraction-like pattern with a central peak at zero and symmetric peaks at 193 ° and 415 °. We observed similar dynamics in a robotic snake using shape-based control. This suggests that this sand-specialist snake adheres to its preferred waveform as opposed to changing in response to heterogeneity.

  13. Parasitic fauna of captive snakes in Tamilnadu, India

    Directory of Open Access Journals (Sweden)

    Nakulan Valsala Rajesh

    2015-07-01

    Full Text Available Objective: To study the parasitic fauna on serpentines under captive condition in zoological park of Tamilnadu, India. Methods: Fecal samples were collected from (n = 247 serpentines, Arignar Anna Zoological Park (n = 22, Vandalur, Tamilnadu, India and Snake Park (n = 27, Guindy, Tamilnadu, India and screened for endoparasites using sedimentation techniques. Ectoparasites were also reported in this study. Results: Coprological examination (n = 247 from captive snakes (n = 49 on random analysis revealed strongyles were predominant in Arignar Anna Zoological Park, Vandalur and Snake Park, Guindy, however the parasites were absent in king cobras (Ophiophagus hannah. Eggs of Capillaria sp. showed less predominance in Vandalur and Gunidy. Rat snakes [Ptyas mucosus (P. mucosus] showed higher prevalence of strongyle infection in Vandalur, and Russell’s viper (Daboia russelii showed higher prevalence in Guindy. Study on ectoparasites revealed Aponomma gerviasii ticks in P. mucosus, Indian cobras (Naja naja, king cobras (Ophiophagus hannah, reticulated pythons (Python reticulates and Indian rock pythons (Python molurus, among them, the most heavy infestation was documented in P. mucosus (n = 9. Conclusions: Confinement favour stress and dysecdysis in captive condition affect the health status of snakes in zoological park.

  14. Debunking the viper's strike: harmless snakes kill a common assumption.

    Science.gov (United States)

    Penning, David A; Sawvel, Baxter; Moon, Brad R

    2016-03-01

    To survive, organisms must avoid predation and acquire nutrients and energy. Sensory systems must correctly differentiate between potential predators and prey, and elicit behaviours that adjust distances accordingly. For snakes, strikes can serve both purposes. Vipers are thought to have the fastest strikes among snakes. However, strike performance has been measured in very few species, especially non-vipers. We measured defensive strike performance in harmless Texas ratsnakes and two species of vipers, western cottonmouths and western diamond-backed rattlesnakes, using high-speed video recordings. We show that ratsnake strike performance matches or exceeds that of vipers. In contrast with the literature over the past century, vipers do not represent the pinnacle of strike performance in snakes. Both harmless and venomous snakes can strike with very high accelerations that have two key consequences: the accelerations exceed values that can cause loss of consciousness in other animals, such as the accelerations experienced by jet pilots during extreme manoeuvres, and they make the strikes faster than the sensory and motor responses of mammalian prey and predators. Both harmless and venomous snakes can strike faster than the blink of an eye and often reach a target before it can move. © 2016 The Author(s).

  15. Does aquatic foraging impact head shape evolution in snakes?

    Science.gov (United States)

    Segall, Marion; Cornette, Raphaël; Fabre, Anne-Claire; Godoy-Diana, Ramiro; Herrel, Anthony

    2016-08-31

    Evolutionary trajectories are often biased by developmental and historical factors. However, environmental factors can also impose constraints on the evolutionary trajectories of organisms leading to convergence of morphology in similar ecological contexts. The physical properties of water impose strong constraints on aquatic feeding animals by generating pressure waves that can alert prey and potentially push them away from the mouth. These hydrodynamic constraints have resulted in the independent evolution of suction feeding in most groups of secondarily aquatic tetrapods. Despite the fact that snakes cannot use suction, they have invaded the aquatic milieu many times independently. Here, we test whether the aquatic environment has constrained head shape evolution in snakes and whether shape converges on that predicted by biomechanical models. To do so, we used three-dimensional geometric morphometrics and comparative, phylogenetically informed analyses on a large sample of aquatic snake species. Our results show that aquatic snakes partially conform to our predictions and have a narrower anterior part of the head and dorsally positioned eyes and nostrils. This morphology is observed, irrespective of the phylogenetic relationships among species, suggesting that the aquatic environment does indeed drive the evolution of head shape in snakes, thus biasing the evolutionary trajectory of this group of animals. © 2016 The Author(s).

  16. Neurological manifestations of snake bite in Sri Lanka.

    Directory of Open Access Journals (Sweden)

    Seneviratne U

    2002-10-01

    Full Text Available BACKGROUND AND AIMS: Snake bite is an important cause of mortality and morbidity in certain parts of Sri Lanka. This study was designed to determine the offending snakes, neurological manifestations, disease course, and outcome in neurotoxic envenomation. METHODS AND MATERIAL: Fifty six consecutive patients admitted with neurological manifestations following snake bite were studied prospectively. Data were obtained regarding the offending snakes, neurological symptoms, time taken for onset of symptoms, neurological signs, and time taken for recovery. RESULTS: The offending snake was Russell′s viper in 27(48.2%, common and Sri Lankan krait in 19(33.9%, cobra in 3(5.4%, and unidentified in 7(12.5%. Ptosis was the commonest neurological manifestation seen in 48(85.7% followed by ophthalmoplegia (75%, limb weakness (26.8%, respiratory failure (17.9%, palatal weakness (10.7%, neck muscle weakness (7.1%, and delayed sensory neuropathy (1.8%. Neurological symptoms were experienced usually within 6 hours after the bite. Following administration of antivenom, the signs of recovery became evident within a few hours to several days. The duration for complete recovery ranged from four hours to two weeks. CONCLUSIONS: Complete recovery of neuromuscular weakness was observed in all patients except for one who died with intracerebral haemorrhage shortly after admission.

  17. Gravity and the Evolution of Cardiopulmonary Morphology in Snakes

    Science.gov (United States)

    Lillywhite, Harvey B.; Albert, James S.; Sheehy, Coleman M.; Seymour, Roger S.

    2011-01-01

    Physiological investigations of snakes have established the importance of heart position and pulmonary structure in contexts of gravity effects on blood circulation. Here we investigate morphological correlates of cardiopulmonary physiology in contexts related to ecology, behavior and evolution. We analyze data for heart position and length of vascular lung in 154 species of snakes that exhibit a broad range of characteristic behaviors and habitat associations. We construct a composite phylogeny for these species, and we codify gravitational stress according to species habitat and behavior. We use conventional regression and phylogenetically independent contrasts to evaluate whether trait diversity is correlated with gravitational habitat related to evolutionary transitions within the composite tree topology. We demonstrate that snake species living in arboreal habitats, or which express strongly climbing behaviors, possess relatively short blood columns between the heart and the head, as well as relatively short vascular lungs, compared to terrestrial species. Aquatic species, which experience little or no gravity stress in water, show the reverse – significantly longer heart–head distance and longer vascular lungs. These phylogenetic differences complement the results of physiological studies and are reflected in multiple habitat transitions during the evolutionary histories of these snake lineages, providing strong evidence that heart–to–head distance and length of vascular lung are co–adaptive cardiopulmonary features of snakes. PMID:22079804

  18. Prevalence of neutralising antibodies against adenoviruses in lizards and snakes.

    Science.gov (United States)

    Ball, Inna; Ofner, Sabine; Funk, Richard S; Griffin, Chris; Riedel, Ulf; Möhring, Jens; Marschang, Rachel E

    2014-10-01

    Adenoviruses (AdVs) are relatively common in lizards and snakes, and several genetically distinct AdVs have been isolated in cell culture. The aims of this study were to examine serological relationships among lizard and snake AdVs and to determine the frequency of AdV infections in these species. Isolates from a boa constrictor (Boa constrictor), a corn snake (Pantherophis gutattus) and a central bearded dragon (Pogona vitticeps), and two isolates from helodermatid lizards (Heloderma horridum and H. suspectum) were used in neutralisation tests for the detection of antibodies in plasma from 263 lizards from seven families (including 12 species) and from 141 snakes from four families (including 28 species) from the USA and Europe. Most lizard and snake samples had antibodies against a range of AdV isolates, indicating that AdV infection is common among these squamates. Neutralisation tests with polyclonal antibodies raised in rabbits demonstrated serological cross-reactivity between both helodermatid lizard isolates. However, squamate plasma showed different reactions to each of these lizard isolates in neutralisation tests. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Retrospective review of snake bite victims.

    Science.gov (United States)

    Nazim, Muhammad H; Gupta, Sanjay; Hashmi, Syed; Zuberi, Jamshed; Wilson, Alison; Roberts, Lawrence; Karimi, Kamran

    2008-01-01

    Venomous snakebites are a rare but dangerous and potentially deadly condition in the U.S.. Most bites in the U. S. result from envenomation with snakes of the family Viperidae, subfamily Crotalinae, which includes rattlesnakes and copperheads. Treatment includes a comprehensive work-up to look for possible hematologic, neurologic, renal, and cardiovascular abnormalities, local wound care, systemic antivenom administration, tetanus prophylaxis, antibiotics in the presence of infection and surgical treatment if needed, which may include debridement, fasciotomy and rarely amputation. All these patients should be observed for a minimum of 8 hours. Any evidence of envenomation mandates a minimum of 24 hours of in-hospital observation. A grading system to classify the severity of envenomation is described. The most commonly used antivenom in the U.S. is CroFab, which has a much lower incidence of acute or delayed allergic reactions compared to the older antivenoms. When allergic reactions do occur, they are usually of mild to moderate severity. With the improved risk-benefit ratio of CroFab, antivenom is indicated with any grade of envenomation. In this a retrospective study, we will review our experience with 25 snakebite victims admitted to the West Virginia University over a five years period.

  20. 78 FR 76175 - Notice of Public Meeting for the John Day-Snake Resource Advisory Council

    Science.gov (United States)

    2013-12-16

    ... Bureau of Land Management Notice of Public Meeting for the John Day-Snake Resource Advisory Council... U.S. Department of the Interior, Bureau of Land Management (BLM), the John Day-Snake Resource Advisory Council (RAC) will meet as indicated below: DATES: The John Day-Snake RAC will hold a public...

  1. 75 FR 5803 - John Day/Snake Resource Advisory Council; Meetings

    Science.gov (United States)

    2010-02-04

    ... Bureau of Land Management John Day/Snake Resource Advisory Council; Meetings AGENCY: Bureau of Land Management, Interior. ACTION: Meeting Notice for the John Day/Snake Resource Advisory Council. SUMMARY.... Department of the Interior, Bureau of Land Management (BLM) John Day/Snake Resource Advisory Council (JDSRAC...

  2. 78 FR 64236 - Notice of Public Meeting for the John Day; Snake Resource Advisory Council

    Science.gov (United States)

    2013-10-28

    ... Bureau of Land Management Notice of Public Meeting for the John Day; Snake Resource Advisory Council... U.S. Department of the Interior, Bureau of Land Management (BLM), the John Day--Snake Resource Advisory Council (RAC) will meet as indicated below: DATES: The John Day--Snake RAC will hold a public...

  3. 77 FR 3115 - Safety Zone; Grain-Shipment Vessels, Columbia and Snake Rivers

    Science.gov (United States)

    2012-01-23

    ... 165 [Docket No. USCG-2011-1069] RIN 1625-AA00 Safety Zone; Grain-Shipment Vessels, Columbia and Snake... Snake Rivers. This safety zone extends to waters 500 yards ahead of these vessels and 200 yards abeam... will threaten safe navigation and the safety of persons and property on the Columbia and Snake rivers...

  4. Prevalence of Amblyomma gervaisi ticks on captive snakes in Tamil Nadu.

    Science.gov (United States)

    Catherine, B R; Jayathangaraj, M G; Soundararajan, C; Bala Guru, C; Yogaraj, D

    2017-12-01

    Ticks are the important ectoparasites that occur on snakes and transmit rickettsiosis, anaplasmosis and ehrlichiosis. A total of 62 snakes (Reticulated python, Indian Rock Python, Rat snakes and Spectacled cobra) were examined for tick infestation at Chennai Snake Park Trust (Guindy), Arignar Anna Zoological Park (Vandalur) and Rescue centre (Velachery) in Tamil Nadu from September, 2015 to June, 2016. Ticks from infested snakes were collected and were identified as Amblyomma gervaisi (previously known as Aponomma gervaisi). Overall occurrence of tick infestation on snakes was 66.13%. Highest prevalence of tick infestation was observed more on Reticulated Python (Python reticulatus, 90.91%) followed by Indian Rock Python (Python molurus, 88.89%), Spectacled cobra (Naja naja, 33.33%) and Rat snake (Ptyas mucosa, 21.05%). Highest prevalence of ticks were observed on snakes reared at Chennai Snake Park Trust, Guindy (83.33%), followed by Arignar Anna Zoological Park, Vandalur (60.00%) and low level prevalence of 37.50% on snakes at Rescue centre, Velachery. Among the system of management, the prevalence of ticks were more on captive snakes (70.37%) than the free ranging snakes (37.5%). The presences of ticks were more on the first quarter when compared to other three quarters and were highly significant (P ≤ 0.01).

  5. Body temperature variations of the Louisiana pine snake (Pituophis ruthveni) in a longleaf pine ecosystem

    Science.gov (United States)

    John G. Himes; Laurence M. Hardy; D. Craig Rudolph; Shirley J. Burgdorf

    2006-01-01

    The thermal ecology of the Louisiana pine snake, Pituophis ruthveni, was studied from 1993-97 in Louisiana and Texas. All snakes were implanted with temperature-sensitive radiotransmitters. Temperatures were recorded from snakes located above ground and underground and were compared between size and sex classes (juveniles, adult males, adult females). Associated air...

  6. A retrospective review of snake bite victims admitted in a tertiary ...

    African Journals Online (AJOL)

    Objective: Snake bite remains major public health problem worldwide. We present our experience with cases of snake bites managed in our tertiary care teaching center of South India. Materials and Methods:The details of all patients with snake bite admitted to a tertiary teaching care hospital from. 2010 to 2012 were ...

  7. Secondary analysis of snake bite data in the Western Region of Ghana

    African Journals Online (AJOL)

    Background: A snake bite is an injury caused by a bite from a snake, often resulting in puncture wounds, amputations and sometimes envenomation. Envenoming resulting from snake bite is a particularly important public health problem in rural areas of tropical and sub-tropical countries in Africa. This paper reports the ...

  8. Snake Bite: A review of Current Literature | Dreyer | East and Central ...

    African Journals Online (AJOL)

    Snake bite is a significant public health problem in rural areas of many parts of the world1. Venomous snakes are found worldwide, except for a few islands and the frozen environments. Snake bite most commonly affects those living in the tropical and sub-tropical areas of Africa, Asia, the. Americas and Oceania.

  9. Are Diet Preferences Associated to Skulls Shape Diversification in Xenodontine Snakes?

    Science.gov (United States)

    Klaczko, Julia; Sherratt, Emma; Setz, Eleonore Z F

    2016-01-01

    Snakes are a highly successful group of vertebrates, within great diversity in habitat, diet, and morphology. The unique adaptations for the snake skull for ingesting large prey in more primitive macrostomatan snakes have been well documented. However, subsequent diversification in snake cranial shape in relation to dietary specializations has rarely been studied (e.g. piscivory in natricine snakes). Here we examine a large clade of snakes with a broad spectrum of diet preferences to test if diet preferences are correlated to shape variation in snake skulls. Specifically, we studied the Xenodontinae snakes, a speciose clade of South American snakes, which show a broad range of diets including invertebrates, amphibians, snakes, lizards, and small mammals. We characterized the skull morphology of 19 species of xenodontine snakes using geometric morphometric techniques, and used phylogenetic comparative methods to test the association between diet and skull morphology. Using phylogenetic partial least squares analysis (PPLS) we show that skull morphology is highly associated with diet preferences in xenodontine snakes.

  10. Pattern of First-Aid Measures Used by Snake-bite Patients and ...

    African Journals Online (AJOL)

    The use of first aid measures in the management of snake bite by patients in rural communities in Africa is a popular practice. Records of 103 snake bite patients admitted at Zamko Comprehensive Health Centre, were retrieved and reviewed. 84 (81.6%) of the 103 cases with snake bite used first aid measures. Common first ...

  11. A retrospective review of snake bite victims admitted in a tertiary ...

    African Journals Online (AJOL)

    Objective: Snake bite remains major public health problem worldwide. We present our experience with cases of snake bites managed in our tertiary care teaching center of South India. Materials and Methods: The details of all patients with snake bite admitted to a tertiary teaching care hospital from 2010 to 2012 were ...

  12. Hibernation Site Philopatry in Northern Pine Snakes (Pituophis melanoleucus) in New Jersey

    Science.gov (United States)

    Burger, Joanna; Zappalorti, Robert

    2015-01-01

    Northern Pine Snakes (Pituophis melanoleucus) are one of the few snakes that spend the winter in underground hibernacula that they excavate. We report the use of hibernacula by Pine Snakes from 1986 to 2012 in the New Jersey Pine Barrens. We determined whether philopatry to a specific hibernaculum varied as a function of age, sex, and location of the hibernaculum. Three hibernacula were occupied nearly continuously for 27 yr by 1 to 27 snakes each year. With known-age snakes (N = 120), captured mainly as hatchlings and 2-yr-olds, we found that 23% were always philopatric. Philopatry was related to age of last capture, sex, and capture location. Philopatry was higher for 1) females compared with males, 2) snakes at two solitary hibernacula compared with a hibernaculum complex, and 3) snakes 6 yr old or younger, compared with older snakes. Of hatchlings found hibernating, 24% used the same hibernation site the next year, and 38% were located at year 4 or later. The number of snakes that always used the same hibernation site declined with the age of last capture. Snakes that entered hibernacula as hatchlings were found more often than those that entered as 2-yr-olds. For the seven snakes that were 14 yr or older, females were found 64– 86 % of the time, whereas males were found 15 to 50% of the time. Understanding the behavior and habitat requirements of snakes during different seasons is central to life-history analysis and for conserving viable populations. PMID:27011392

  13. Testing the snake-detection hypothesis: larger early posterior negativity in humans to pictures of snakes than to pictures of other reptiles, spiders and slugs.

    Science.gov (United States)

    Van Strien, Jan W; Franken, Ingmar H A; Huijding, Jorg

    2014-01-01

    According to the snake detection hypothesis (Isbell, 2006), fear specifically of snakes may have pushed evolutionary changes in the primate visual system allowing pre-attentional visual detection of fearful stimuli. A previous study demonstrated that snake pictures, when compared to spiders or bird pictures, draw more early attention as reflected by larger early posterior negativity (EPN). Here we report two studies that further tested the snake detection hypothesis. In Study 1, we tested whether the enlarged EPN is specific for snakes or also generalizes to other reptiles. Twenty-four healthy, non-phobic women watched the random rapid serial presentation of snake, crocodile, and turtle pictures. The EPN was scored as the mean activity at occipital electrodes (PO3, O1, Oz, PO4, O2) in the 225-300 ms time window after picture onset. The EPN was significantly larger for snake pictures than for pictures of the other reptiles. In Study 2, we tested whether disgust plays a role in the modulation of the EPN and whether preferential processing of snakes also can be found in men. 12 men and 12 women watched snake, spider, and slug pictures. Both men and women exhibited the largest EPN amplitudes to snake pictures, intermediate amplitudes to spider pictures and the smallest amplitudes to slug pictures. Disgust ratings were not associated with EPN amplitudes. The results replicate previous findings and suggest that ancestral priorities modulate the early capture of visual attention.

  14. Backward Masked Snakes and Guns Modulate Spatial Attention

    Directory of Open Access Journals (Sweden)

    Joshua M. Carlson

    2009-10-01

    Full Text Available Fearful faces are important social cues that alert others of potential threat. Even backward masked fearful faces facilitate spatial attention. However, visual stimuli other than fearful faces can signal potential threat. Indeed, unmasked snakes and spiders modulate spatial attention. Yet, it is unclear if the rapid threat-related facilitation of spatial attention to backward masked stimuli is elicited by non-face threat cues. Evolutionary theories claim that phylogenetic threats (i.e. snakes and spiders should preferentially elicit an automatic fear response, but it is untested as to whether this response extends to enhancements in spatial attention under restricted processing conditions. Thirty individuals completed a backward masking dot-probe task with both evolutionary relevant and irrelevant threat cues. The results suggest that backward masked visual fear stimuli modulate spatial attention. Both evolutionary relevant (snake and irrelevant (gun threat cues facilitated spatial attention.

  15. The distribution and identification of dangerously venomous Australian terrestrial snakes.

    Science.gov (United States)

    Shea, G M

    1999-12-01

    The identification of dangerous Australian snakes is important in instituting therapy for envenomation. Despite the availability of a number of identification guides with varying degrees of generality, identification can be problematic for several reasons. These include a diversity of common names, many of which are inappropriate or regionally applied to different species, identification keys that focus on variable features, intraspecific variation and interspecific convergence in colouration, and recent changes in scientific nomenclature of species and genera. Geographic distribution of the dangerously venomous species can be a useful aid to identification, by limiting the range of options in a region. However, delineation of the limits of distribution relies on fine scale mapping beyond the resolution of most identification guides. This article provides a summary of the geographic limits of the dangerously venomous Australian snakes, with particular emphasis on major population centres, and clarifies some problems in identification, particularly among brown-coloured snakes.

  16. [Application of rapid PCR to authenticate medicinal snakes].

    Science.gov (United States)

    Chen, Kang; Jiang, Chao; Yuan, Yuan; Huang, Lu-Qi; Li, Man

    2014-10-01

    To obtained an accurate, rapid and efficient method for authenticate medicinal snakes listed in Chinese Pharmacopoeia (Zaocysd humnades, Bungarus multicinctus, Agkistrodon acutus), a rapid PCR method for authenticate snakes and its adulterants was established based on the classic molecular authentication methods. DNA was extracted by alkaline lysis and the specific primers were amplified by two-steps PCR amplification method. The denatured and annealing temperature and cycle numbers were optimized. When 100 x SYBR Green I was added in the PCR product, strong green fluorescence was visualized under 365 nm UV whereas adulterants without. The whole process can complete in 30-45 minutes. The established method provides the technical support for authentication of the snakes on field.

  17. Satiety and eating patterns in two species of constricting snakes

    DEFF Research Database (Denmark)

    Nielsen, Torben T.; Jacobsen, Lars Magnus W.; Wang, Tobias

    2011-01-01

    Satiety has been studied extensively in mammals, birds and fish but very little information exists on reptiles. Here we investigate time-dependent satiation in two species of constricting snakes, ball pythons (Python regius) and yellow anacondas (Eunectes notaeus). Satiation was shown to depend...... on both fasting time and prey size. In the ball pythons fed with mice of a relative prey mass RPM (mass of the prey/mass of the snake×100) of 15%, we observed a satiety response that developed between 6 and 12h after feeding, but after 24h pythons regained their appetite. With an RPM of 10% the pythons...... a significant decrease in handling time between the first and the second prey and a positive correlation between handling time and the mass of the snake....

  18. Antioxidant activity and phytochemical compounds of snake fruit (Salacca Zalacca)

    Science.gov (United States)

    Suica-Bunghez, I. R.; Teodorescu, S.; Dulama, I. D.; Voinea, O. C.; imionescu, S.; Ion, R. M.

    2016-06-01

    Snake fruit (Salacca zalacca) is a palm tree species, which is found in Malaysia and Indonesia. This study was conducted to investigate and compare the composition, total phenolic, flavonoid, tanins and monoterpenoids contents in the core and shell fruits. Concentration values of extracts were obtained from standard curves obtained. Antioxidant activity was determined using DPPH method. For all methods it was used the UV-VIS Specord M40, using different wavelength. The infrared spectral analysis was carried out to caracterized the type of functional group existent in snake fruit parts (shell and core).

  19. Gait, Stability and Movement of Snake-Like Robots

    Directory of Open Access Journals (Sweden)

    Shengyong Chen

    2012-11-01

    Full Text Available This paper provides theoretical analysis of some key features of snake-like robot locomotion. Inspired by the moving mechanism of animals, the snake robot built with simple modules is numerically controlled. A most common method for its locomotion is to apply a central pattern generator to efficiently generate the control signals of gait and movement. This paper analyses stability, crawling gait, moving velocity, climbing capability, the capability to cross ditches and avoid obstacles, etc. Mathematical models and simulations show the theoretical validity and robot capabilities.

  20. [Snake venom metalloproteinases: structure, biosynthesis and function(s)].

    Science.gov (United States)

    Limam, I; El Ayeb, M; Marrakchi, N

    2010-01-01

    The biochemical and the pharmacological characterization of snake venoms revealed an important structural and functional polymorphism of proteins which they contain. Among them, snake venom metalloproteases (SVMPs) constitute approximatively 20 to 60% of the whole venom proteins. During the last decades, a significant progress was performed against structure studies and the biosynthesis of the SVMPs. Indeed, several metalloproteases were isolated and characterized against their structural and pharmacological properties. In this review, we report the most important properties concerning the classification, the structure of the various domains of the SVMPs as well as their biosynthesis and their activities as potential therapeutic agents.

  1. Presence of Porocephalus clavatus (Arthropoda: Porocephalidae) in Peruvian Boidae snakes.

    Science.gov (United States)

    Gomez-Puerta, Luis A; Lopez-Urbina, María T; Gonzalez, Armando E

    2011-09-27

    The pentastome species, Porocephalus clavatus, has been found to infect the lungs of two species of snakes in the family Boidae family (Boa constrictor and Epicrates cenchria). The individual of B. constrictor was collected in the Amazonian rainforest of Departamento Loreto, Peru. The E. cenchria was recovered from the pet trade in Lima, Peru's capital city. A total of 22 P. clavatus were collected and examined from these two snakes. This is the first report of P. clavatus in Peru. The morphology of the parasites and the possible importance in public and animal health are discussed. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Pentastomes (Pentastomida, Armillifer armillatus Wyman, 1848) in snakes from Zambia.

    Science.gov (United States)

    De Meneghi, D

    1999-12-01

    Twenty-three snakes, belonging to eight different species, were collected from rural areas of Zambia and inspected for the presence of pentastomes. Pentastomid parasites were found in four snakes: one African rock python (Python sebae), one puff adder (Bitis arietans) and two Mozambique spitting cobras (Naja mossambica) were infested with a small number of Armillifer armillatus, respectively five, two and one adult parasites. As humans can be incidental/intermediate hosts for reptilian pentastomes, the zoonotic potential of these parasites, especially in tropical countries, is discussed.

  3. Snake bite in dogs and its successful treatment

    Directory of Open Access Journals (Sweden)

    K. J. Ananda

    2009-04-01

    Full Text Available Two dog viz. Labrador and Alsatian cross were presented to the peripheral hospital with a history of frothy salivation, dull, depressed, abnormal gait and with recumbent position. They were diagnosed for snake bite based on the history and physical examination. The hematological parameters showed reduced values of hemoglobin, packed cell volume and increased total leukocyte count. The biochemical values showed elevated levels of alanine aminotransferase and creatinine. The successful treatment was done with anti-snake venom, fluid, corticosteroid, muscuranic receptor antagonist and antibiotic with careful monitoring. [Vet. World 2009; 2(2.000: 66-67

  4. What kills everyone, gives a high for some-Recreational Snake Envenomation.

    Science.gov (United States)

    Shukla, Lekhansh; Reddy, Shiva Shanker; Kandasamy, Arun; Benegal, Vivek

    2017-02-01

    There are multiple reports of recreational snake envenomation describing psychotropic effects in absence of any adverse effects. This is in contradiction with known effects of snake venom. We report a case of a young male who subjected himself to repeated envenomation by a snake purported to be 'Indian Cobra' and experienced a 'high'. However, a direct identification of snake revealed it was a benign 'Rat snake'. We attempt to explain the reported psychological effects as a result of high expectation of rewarding experience, strong suggestion, personality traits and most importantly the dangerous nature of willfully receiving snakebites. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Our Clinical Experiences in Snake Bites

    Directory of Open Access Journals (Sweden)

    Demet Altun

    2016-12-01

    Full Text Available In this study, we evaluate 25 cases who were admitted to the emergency service and transferred to the intensive care unit subsequently due to snakebite, prospectively. Clinical courses, toxic effects, complications and treatment approaches were aimed to be presented. Among the patients, 16 were female and 9 were male; the mean age was 42.1 (17-74 years. It was determined that all the cases were admitted to the hospital during working in the field in Eastern Anatolia Region, between the months of May and June, and between the hours of 15:00 to 18:00. When the cases were considered in terms of bitten body part, 15 were bitten from upper extremity and 10 were bitten from lower extremity. Within an hour the patients were admitted to a health facility with the complaints of nausea, pain, numbness, swelling and redness, and patients were transferred to emergency unit approximately within 1 hour (0.5 to 2 hours following the first intervention. Tetanus immunization is administered in all cases as the first intervention. Antivenom was administered to the 9 (36% of the patients in whom steroid, antihistamine and prophylactic antibiotic therapy was given in the intensive care unit. Under the control of infection clinic, antibiotic therapy was initiated to 13 (52% patients in who cellulitis, abscess, lymphedema and compartment syndrome were developed. Healing was observed approximately within 4 days (2-6 days and recovery was observed in all the cases. Patients admitted due to snake bites should be followed closely for at least 6 to 8 hours. According to the patient’s clinical condition and laboratory test results, early intervention therapy should be regulated and antivenom therapy should be administered in the presence of systemic symptoms.

  6. Diversity of Snakes in Rajegwesi Tourism Area, Meru Betiri National Park

    Directory of Open Access Journals (Sweden)

    Aji Dharma Raharjo

    2015-02-01

    Full Text Available Rajegwesi tourism area is one of the significant tourism areas in Meru Betiri National Park, East Java, Indonesia. The area rich in term of biodiversity which are potential for developed as natural tourism attraction.  The aim of this study is to identify snakes species diversity and its distribution in Rajegwesi tourism area. Field survey was done in Rajegwesi area, namely swamps forest, residential area, rice fields, agriculture area (babatan, resort area, and Plengkang cliff. This study found some snakes, encompasses Colubridae (10 species, Elapidae (four species, and Phytonidae (one species. There are Burmese Python (Python reticulatus, Red-necked Keelback (Rhabdophis subminiatus, Painted Bronzeback Snake (Dendrelaphis Pictus, Black Copper Rat Snake (Coelognathus flavolineatus, Radiated Rat Snake (C. radiatus, Striped Keelback (Xenochrophis vittatus, Checkered Keelback (X. piscator, Spotted Ground Snake (Gongyosoma balioderius, Gold-ringed Cat Snake (Boiga dendrophila, Common Wolf Snake (Lycodon capucinus, Banded Wolf snake (L. subcinctus, Cobra (Naja sputatrix, King Cobra (Ophiophagus hannah, Malayan Krait (Bungarus candidus, and Banded Krait (B. fasciatus was found. These snake habitats distributes at 21 coordinate points. Keywords: conservation, ecotourism, snakes.

  7. EVOLUTION. A four-legged snake from the Early Cretaceous of Gondwana.

    Science.gov (United States)

    Martill, David M; Tischlinger, Helmut; Longrich, Nicholas R

    2015-07-24

    Snakes are a remarkably diverse and successful group today, but their evolutionary origins are obscure. The discovery of snakes with two legs has shed light on the transition from lizards to snakes, but no snake has been described with four limbs, and the ecology of early snakes is poorly known. We describe a four-limbed snake from the Early Cretaceous (Aptian) Crato Formation of Brazil. The snake has a serpentiform body plan with an elongate trunk, short tail, and large ventral scales suggesting characteristic serpentine locomotion, yet retains small prehensile limbs. Skull and body proportions as well as reduced neural spines indicate fossorial adaptation, suggesting that snakes evolved from burrowing rather than marine ancestors. Hooked teeth, an intramandibular joint, a flexible spine capable of constricting prey, and the presence of vertebrate remains in the guts indicate that this species preyed on vertebrates and that snakes made the transition to carnivory early in their history. The structure of the limbs suggests that they were adapted for grasping, either to seize prey or as claspers during mating. Together with a diverse fauna of basal snakes from the Cretaceous of South America, Africa, and India, this snake suggests that crown Serpentes originated in Gondwana. Copyright © 2015, American Association for the Advancement of Science.

  8. Observations on the anterior testicular ducts in snakes with emphasis on sea snakes and ultrastructure in the yellow-bellied sea snake, Pelamis platurus.

    Science.gov (United States)

    Sever, David M; Freeborn, Layla R

    2012-03-01

    The anterior testicular ducts of squamates transport sperm from the seminiferous tubules to the ductus deferens. These ducts consist of the rete testis, ductuli efferentes, and ductus epididymis. Many histological and a few ultrastructural studies of the squamate reproductive tract exist, but none concern the Hydrophiidae, the sea snakes and sea kraits. In this study, we describe the anterior testicular ducts of six species of hydrophiid snakes as well as representatives from the Elapidae, Homolapsidae, Leptotyphlopidae, and Uropeltidae. In addition, we examine the ultrastructure of these ducts in the yellow-bellied Sea Snake, Pelamis platurus, only the third such study on snakes. The anterior testicular ducts are similar in histology in all species examined. The rete testis is simple squamous or cuboidal epithelium and transports sperm from the seminiferous tubules to the ductuli efferentes in the extratesticular epididymal sheath. The ductuli efferentes are branched, convoluted tubules composed of simple cuboidal, ciliated epithelium, and many species possess periodic acid-Schiff+ granules in the cytoplasm. The ductus epididymis at the light microscopy level appears composed of pseudostratified columnar epithelium. At the ultrastructural level, the rete testis and ductuli efferentes of P. platurus possess numerous small coated vesicles and lack secretory vacuoles. Apocrine blebs in the ductuli efferentes, however, indicate secretory activity, possibly by a constitutive pathway. Ultrastructure reveals three types of cells in the ductus epididymis of P. platurus: columnar principal cells, squamous basal cells, and mitochondria-rich apical cells. This is the first report of apical cells in a snake. In addition, occasional principal cells possess a single cilium, which has not been reported in reptiles previously but is known in some birds. Finally, the ductus epididymis of P. platurus differs from other snakes that have been studied in possession of apical, biphasic

  9. Hepatozoon infection prevalence in four snake genera: influence of diet, prey parasitemia levels, or parasite type?

    Science.gov (United States)

    Tomé, Beatriz; Maia, João P M C; Harris, D James

    2012-10-01

    Hepatozoon spp. (Apicomplexa: Haemogregarinidae) are the most commonly reported hemoparasites from snakes. Of over 300 Hepatozoon species identified, more than 120 were described from snakes. However, recent genetic assessments have found Hepatozoon lineages recovered from both prey and predators, indicating that diet may play an important role in the infection of final vertebrate hosts. Here 4 different snake genera with different diets were assessed. Hepatozoon spp. prevalence varied greatly between the genera, but only lineages already identified from potential prey, i.e., gecko and lacertid lizards, were recovered from the snakes. Interestingly, the Hepatozoon spp. lineage known from geckos was the most common in the snakes, but this does not reflect their diet. Higher parasitemia levels, reported for some geckos relative to lacertid lizards, may play a role. Alternatively, this lineage may be more effective at parasitizing snakes or may occur, despite being unrecorded, in other vertebrate groups consumed by snakes.

  10. An antemortem guide for the assessment of stranded Australian sea snakes (Hydrophiinae).

    Science.gov (United States)

    Gillett, Amber K; Flint, Mark; Mills, Paul C

    2014-12-01

    Marine snakes of the subfamily Hydrophiinae are obligate ocean dwellers, unlike their amphibious counterparts, the sea kraits (Laticaudinae), and as such they are often referred to as 'true' sea snakes. This specialization means that the presence of a true sea snake on a beach is atypical and likely indicates disease or injury. Traumatic injuries such as eye, jaw, and spinal lesions have been observed in stranded sea snakes and may present as acute injury or progress to chronic debilitation. Diseases, such as neoplasia, leukemia, and parasite overburden, have also been seen in wild sea snakes, and these animals may present similarly. Sick, moribund, or deceased sea snakes are intermittently found washed ashore along Australian beaches, and these specimens may prove valuable as bioindicators of marine health. This review is intended as a guide to the diagnostic investigation of sick or injured sea snakes by suitably qualified people.

  11. Optimization of AGS Polarized Proton Operation with the Warm Helical Snake

    CERN Document Server

    Takano, Junpei; Bai, Mei; Brown, Kevin A; Gardner, Chris J; Glenn, Joseph; Hattori, Toshiyuki; Huang, Haixin; Luccio, Alfredo U; MacKay, William W; Okamura, Masahiro; Roser, Thomas; Tepikian, Steven; Tsoupas, Nicholaos

    2005-01-01

    A normal conducting helical dipole partial Siberian snake (Warm Snake) has been installed in the Alternating Gradient Synchrotron (AGS) at Brookhaven National Laboratory (BNL) for overcoming all of imperfection depolarizing resonances and reducing the transverse coupling resonances caused by the solenoidal Siberian snake which had been operated in AGS before the last polarized run. The polarized proton beam has been accelerated successfully with the warm snake and the polarization at extraction of the AGS was increased to 50% as opposed to 40% with the solenoidal snake. The magnetic field and beam trajectory in the warm snake was calculated by using the OPERA-3D/TOSCA software. We present optimization of the warm snake with beam during RUN5.

  12. Human young children as well as adults demonstrate 'superior' rapid snake detection when typical striking posture is displayed by the snake.

    Directory of Open Access Journals (Sweden)

    Nobuo Masataka

    2010-11-01

    Full Text Available Humans as well as some nonhuman primates have an evolved predisposition to associate snakes with fear by detecting their presence as fear-relevant stimuli more rapidly than fear-irrelevant ones. In the present experiment, a total of 74 of 3- to 4-year-old children and adults were asked to find a single target black-and-white photo of a snake among an array of eight black-and-white photos of flowers as distracters. As target stimuli, we prepared two groups of snake photos, one in which a typical striking posture was displayed by a snake and the other in which a resting snake was shown. When reaction time to find the snake photo was compared between these two types of the stimuli, its mean value was found to be significantly smaller for the photos of snakes displaying striking posture than for the photos of resting snakes in both the adults and children. These findings suggest the possibility that the human perceptual bias for snakes per se could be differentiated according to the difference of the degree to which their presence acts as a fear-relevant stimulus.

  13. Antivenom Cross-Neutralization of the Venoms of Hydrophis schistosus and Hydrophis curtus, Two Common Sea Snakes in Malaysian Waters

    OpenAIRE

    Choo Hock Tan; Nget Hong Tan; Kae Yi Tan; Kok Onn Kwong

    2015-01-01

    Sea snake envenomation is a serious occupational hazard in tropical waters. In Malaysia, the beaked sea snake (Hydrophis schistosus, formerly known as Enhydrina schistosa) and the spine-bellied sea snake (Hydrophis curtus, formerly known as Lapemis curtus or Lapemis hardwickii) are two commonly encountered species. Australian CSL sea snake antivenom is the definitive treatment for sea snake envenomation; it is unfortunately extremely costly locally and is not widely available or adequately ...

  14. Neurological manifestations in speech after snake bite: A rare case ...

    African Journals Online (AJOL)

    Neurological manifestations in speech after snake bite: A rare case. D Vir, D Gupta, M Modi, N Panda. Abstract. No Abstract. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · http://dx.doi.org/10.4314/pamj.v4i1.53597 · AJOL African Journals Online. HOW TO ...

  15. Rediscovery of the Rare Sea Snake Hydrophis parviceps Smith 1935

    DEFF Research Database (Denmark)

    Rasmussen, Arne R.; Elmberg, Johan; Sanders, Kate L.

    2012-01-01

    Smith's small-headed sea snake, Hydrophis parviceps, was originally described in 1935 from a single type specimen collected in southern Vietnam. Since this time there has been only one further record for the species-a specimen collected near the type locality in 1960 that has since been lost...

  16. An additional trigeminal system in certain snakes possessing infrared receptors

    NARCIS (Netherlands)

    Molenaar, Gerard J.

    1974-01-01

    This communication describes a nucleus and tract of the trigeminal system whose existence is not mentioned in any account of brain stem architecture known to the present author. The structures were first recognised in the brain stem of a giant snake (Python reticulatus) and later were also found

  17. The Protocol of Choice for Treatment of Snake Bite

    Directory of Open Access Journals (Sweden)

    Afshin Mohammad Alizadeh

    2016-01-01

    Full Text Available The aim of the current study is to compare three different methods of treatment of snake bite to determine the most efficient one. To unify the protocol of snake bite treatment in our center, we retrospectively reviewed files of the snake-bitten patients who had been referred to us between 2010 and 2014. They were contacted for follow-up using phone calls. Demographic and on-arrival characteristics, protocol used for treatment (WHO/Haddad/GF, and outcome/complications were evaluated. Patients were entered into one of the protocol groups and compared. Of a total of 63 patients, 56 (89% were males. Five, 19, and 28 patients were managed by Haddad, WHO, or GF protocols, respectively. Eleven patients had fallen into both GF and WHO protocols and were excluded. Serum sickness was significantly more common when WHO protocol was used while 100% of the compartment syndromes and 71% of deformities had been reported after GF protocol. The most important complications were considered to be deformity, compartment syndrome, and amputation and were more frequent after the use of WHO and GF protocols (23.1% versus 76.9%; none in Haddad; P = NS. Haddad protocol seems to be the best for treatment of snake-bitten patients in our region. However, this cannot be strictly concluded because of the limited sample size and nonsignificant P values.

  18. Effects of oceanic salinity on body condition in sea snakes.

    Science.gov (United States)

    Brischoux, François; Rolland, Virginie; Bonnet, Xavier; Caillaud, Matthieu; Shine, Richard

    2012-08-01

    Since the transition from terrestrial to marine environments poses strong osmoregulatory and energetic challenges, temporal and spatial fluctuations in oceanic salinity might influence salt and water balance (and hence, body condition) in marine tetrapods. We assessed the effects of salinity on three species of sea snakes studied by mark-recapture in coral-reef habitats in the Neo-Caledonian Lagoon. These three species include one fully aquatic hydrophiine (Emydocephalus annulatus), one primarily aquatic laticaudine (Laticauda laticaudata), and one frequently terrestrial laticaudine (Laticauda saintgironsi). We explored how oceanic salinity affected the snakes' body condition across various temporal and spatial scales relevant to each species' ecology, using linear mixed models and multimodel inference. Mean annual salinity exerted a consistent and negative effect on the body condition of all three snake species. The most terrestrial taxon (L. saintgironsi) was sensitive to salinity over a short temporal scale, corresponding to the duration of a typical marine foraging trip for this species. In contrast, links between oceanic salinity and body condition in the fully aquatic E. annulatus and the highly aquatic L. laticaudata were strongest at a long-term (annual) scale. The sophisticated salt-excreting systems of sea snakes allow them to exploit marine environments, but do not completely overcome the osmoregulatory challenges posed by oceanic conditions. Future studies could usefully explore such effects in other secondarily marine taxa such as seabirds, turtles, and marine mammals.

  19. Snake Creek embankment research study subsides for season

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Snake Creek Embankment on U.S. Highway 83 between Lake Audubon and Lake Sakakawea was home to a research project on bird strikes with power lines this year. This...

  20. Effect of Subject Control and Graduated Exposure on Snake Phobias

    Science.gov (United States)

    Hepner, Alain; Cauthen, Nelson R.

    1975-01-01

    The influence of two of the variables in Leitenberg's graduated exposure technique for treating phobias, graduated exposure and subject control of the exposure time, was investigated using 15 snake-phobic subjects. Subjective fear significantly decreased from pretesting to posttesting. (Author)

  1. Gourds: Bitter, Bottle, Wax, Snake, Sponge and Ridge

    Science.gov (United States)

    Minor cucurbits include bitter gourd, bottle gourd, wax gourd, snake gourd, and sponge and ridge gourd, which are significant dietary sources of nutrients such as vitamin A and C, iron and calcium. These cucurbits are cultivated and marketed by smallholder farmers and remain important components of ...

  2. Spectral transmittance of the spectacle scale of snakes and geckos

    NARCIS (Netherlands)

    Doorn, van K.; Sivak, J.G.

    2015-01-01

    The spectral transmittance of the optical media of the eye plays a substantial role in tuning the spectrum of light available for capture by the retina. Certain squamate reptiles, including snakes and most geckos, shield their eyes beneath a layer of transparent, cornified skin called the

  3. A review of the hispaniolan colubrid snake Genus Ialtris

    NARCIS (Netherlands)

    Schwartz, Albert; Rossman, Douglas A.

    1976-01-01

    Of the four endemic Hispaniolan genera of colubrid snakes, the least known is Ialtris Cope. Two species of Ialtris are recognized, each monotypic – dorsalis Günther and parishi Cochran. Neither has been commonly collected. COCHRAN (1941 : 375) listed 12 specimens of I. dorsalis in American

  4. The Egg-Eating Snake, Introductory Problem, Explorations in Biology.

    Science.gov (United States)

    Mid-Continent Regional Educational Lab., Inc., Kansas City, MO.

    The booklet is designed as an introduction to a series of topics which use the same format, and which are published separately. A series of photographs of a snake eating an egg are used to ask students to identify a puzzling event that they would want to investigate if they were biologists. A scrambled programed text format is used to direct…

  5. Australia´s Dangerous Snakes Identification, Biology and Envenoming

    DEFF Research Database (Denmark)

    Mirtschin, Peter; Redsted Rasmussen, Arne; Weinstein, Scott A

    2017-01-01

    , the environmental roles of these snakes and the threats that are causing the decline of many of these reptiles are discussed. Drawing on the authors’ experience in the fields of herpetology, toxinology and clinical medicine, this book stimulates respect and admiration and dispels fear of Australia’s fascinating...

  6. Fascinating and forgotten: the conservation status of marine elapid snakes

    DEFF Research Database (Denmark)

    Redsted Rasmussen, Arne

    2013-01-01

    Abstract.—An assessment of marine elapid snakes found 9% of marine elapids are threatened with extinction, and an additional 6% are Near Threatened. A large portion (34%) is Data Deficient. An analysis of distributions revealed the greatest species diversity is found in Southeast Asia and norther...

  7. Natural Inhibitors of Snake Venom Metalloendopeptidases: History and Current Challenges

    Science.gov (United States)

    Bastos, Viviane A.; Gomes-Neto, Francisco; Perales, Jonas; Neves-Ferreira, Ana Gisele C.; Valente, Richard H.

    2016-01-01

    The research on natural snake venom metalloendopeptidase inhibitors (SVMPIs) began in the 18th century with the pioneering work of Fontana on the resistance that vipers exhibited to their own venom. During the past 40 years, SVMPIs have been isolated mainly from the sera of resistant animals, and characterized to different extents. They are acidic oligomeric glycoproteins that remain biologically active over a wide range of pH and temperature values. Based on primary structure determination, mammalian plasmatic SVMPIs are classified as members of the immunoglobulin (Ig) supergene protein family, while the one isolated from muscle belongs to the ficolin/opsonin P35 family. On the other hand, SVMPIs from snake plasma have been placed in the cystatin superfamily. These natural antitoxins constitute the first line of defense against snake venoms, inhibiting the catalytic activities of snake venom metalloendopeptidases through the establishment of high-affinity, non-covalent interactions. This review presents a historical account of the field of natural resistance, summarizing its main discoveries and current challenges, which are mostly related to the limitations that preclude three-dimensional structural determinations of these inhibitors using “gold-standard” methods; perspectives on how to circumvent such limitations are presented. Potential applications of these SVMPIs in medicine are also highlighted. PMID:27571103

  8. Sex, snakes and violence / Sherwin Das, Tim Ochser

    Index Scriptorium Estoniae

    Das, Sherwin

    2006-01-01

    Patrick Süskindi krimiromaani "Parfüüm" ekraniseering "Perfume: The Story of a Murderer" : režissöör Tom Tykver : Ameerika Ühendriigid - Saksamaa 2006. Õuduspõnevik "Maod lennukis" ("Snakes on a Plane") : režissöör David R. Ellis : Ameerika Ühendriigid 2006

  9. Diet of the Louisiana pine snake (Pituophis ruthveni)

    Science.gov (United States)

    D. Craig Rudolph; Christopher A. Melder; Josh Pierce; Richard R. Schaefer; Beau Gregory

    2012-01-01

    The Louisiana Pine Snake (Pituophis ruthveni) is a large-bodied constrictor endemic to western Louisiana and eastern Texas (Sweet and Parker 1991). Surveys suggest that the species has declined in recent decades and is now restricted to isolated habitat patches (Reichling 1995; Rudolph et al. 2006). Pituophis ruthveni is listed as...

  10. An Unusual Case of Acute Asthma after Snake Bite

    African Journals Online (AJOL)

    TNHJOURNALPH

    These presynaptically acting toxins exhibit phospholipase A;. activity. [7]. Cardiotoxins which cause augmentation of myocardial contractions at low concentration have been identified from cobra venoms [8]. Crotamine rattle snake venoms have a specific and unique effect on the sodium channel of excitable membrane [8].

  11. A review of diagnostic imaging of snakes and lizards.

    Science.gov (United States)

    Banzato, T; Hellebuyck, T; Van Caelenberg, A; Saunders, J H; Zotti, A

    2013-07-13

    Snakes and lizards are considered 'stoic' animals and often show only non-specific signs of illness. Consequently, diagnostic imaging--along with clinical examination and laboratory tests--is gaining importance in making a final diagnosis and establishing a correct therapy. The large number of captive snake and lizard species commonly kept as pets, together with the high inter- and intraspecific morphological variability that is innate in these animals, make the analysis of diagnostic images challenging for the veterinary practitioner. Moreover, a thorough knowledge of the anatomy, physiology and pathology of the species that are the object of clinical investigation is mandatory for the correct interpretation of diagnostic images. Despite the large amount of clinical and scientific work carried out in the past two decades, the radiographic features of snakes and lizards have not undergone systematic description, and therefore veterinarians often have to rely mostly on anatomical studies rather than radiological literature. The aim of this paper is to review the most commonly used diagnostic imaging modalities, as well as to provide an overview of the available international original studies and scientific reviews describing the normal and pathological imaging features in snakes and lizards.

  12. Taste buds in the palatal mucosa of snakes | Berkhoudt | African ...

    African Journals Online (AJOL)

    An examination of the oral mucosa of Crotalus and several Scolecophidia revealed the presence of taste buds. The taste buds in these two divergent groups of snakes are similar in appearance, and correspond to previous descriptions of gustatory organs in other reptiles. Few taste buds were present in any specimen, and ...

  13. Takotsubo cardiomyopathy in a snake bite victim: a case report ...

    African Journals Online (AJOL)

    Takotsubo cardiomyopathy occurs in patients with severe emotional or physiologic stress. The prognosis is usually favorable, and the left ventricular wall motion dyskinesis normalizes within days to weeks. In this paper we report a case of snake bite complicated by takotsubo cardiomyopathy. We advise physicians to ...

  14. Pitfalls to avoid when using phage display for snake toxins

    DEFF Research Database (Denmark)

    Laustsen, Andreas Hougaard; Lauridsen, Line Præst; Lomonte, Bruno

    2017-01-01

    Antivenoms against bites and stings from snakes, spiders, and scorpions are associated with immunological side effects and high cost of production, since these therapies are still derived from the serum of hyper-immunized production animals. Biotechnological innovations within envenoming therapies...

  15. Attention bias modification in specific fears: Spiders versus snakes.

    Science.gov (United States)

    Luo, Xijia; Ikani, Nessa; Barth, Anja; Rengers, Lea; Becker, Eni; Rinck, Mike

    2015-12-01

    Attention Bias Modification (ABM) is used to manipulate attention biases in anxiety disorders. It has been successful in reducing attention biases and anxious symptoms in social anxiety and generalized anxiety, but not yet in specific fears and phobias. We designed a new version of the dot-probe training task, aiming to train fearful participants' attention away from or towards pictures of threatening stimuli. Moreover, we studied whether the training also affected participants' avoidance behavior and their physical arousal upon being confronted with a real threat object. In Experiment 1, students with fear of spiders were trained. We found that the attention manipulation was successful, but the training failed to affect behavior or arousal. In Experiment 2, the same procedure was used on snake-fearful students. Again, attention was trained in the expected directions. Moreover, participants whose attention had been trained away from snakes showed lower physiological arousal upon being confronted with a real snake. The study involved healthy students with normal distribution of the fear of spider/snake. Future research with clinical sample could help with determining the generalizability of the current findings. The effect of ABM on specific phobia is still in question. The finding in the present study suggested the possibility to alter attentional bias with a dot-probe task with general positive stimuli and this training could even affect the behavior while encountering a real threat. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Of Mice and Snakes: A Tail of Oct4.

    Science.gov (United States)

    Shylo, Natalia A; Weatherbee, Scott D

    2016-08-08

    The vertebrate axial skeleton comprises regions of specialized vertebrae, which vary in length between lineages. Aires et al. (2016) uncover a key role for Oct4 in determining trunk length in mice. Additionally, a heterochronic shift in Oct4 expression may underlie the extreme elongation of the trunk in snakes. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Acid Mine Drainage Potential of the Coral Snake Waste Dump ...

    African Journals Online (AJOL)

    This paper assessed the Acid Mine Drainage (AMD) potential of the Coral Snake Waste Dump located close to the Enkansu and Kaw streams in Obuasi. Ten water and fifty rock samples were analysed for physico-chemical parameters. Acid Base Accounting (ABA) determinations using static methods were employed to ...

  18. High-throughput epitope profiling of snake venom toxins

    DEFF Research Database (Denmark)

    Engmark, Mikael; Andersen, Mikael Rørdam; Laustsen, Andreas Hougaard

    Insight into the molecular details of polyclonal antivenom antibody specificity is a prerequisite for accurate prediction of cross-reactivity and can provide a basis for design of novel antivenoms. In this work, a highthroughput approach was applied to characterize linear elements in epitopes in ...... toxins from four African mamba and three neurotoxic cobra snakes obtained from public databases....

  19. SNAKE VENOM INSTABILITY • Department of Physiology, Medical ...

    African Journals Online (AJOL)

    It is generally accepted that the biological activities of snake venom dried in vacuum at room temperature remain unaltered (Christensen 1955). The possibility of an alteration in biochemical properties due to the method of drying has been demonstrated by Bjork &. Boman (1959), but this would not necessarily influence the ...

  20. Knowledge and management of snake bite by general practitioners ...

    African Journals Online (AJOL)

    Background: The aim of the study was to determine the knowledge of general practitioners in the rural areas of the Free State and Northern Cape regarding snake bites and their treatment. Methods: Telephonic interviews using structured questionnaires were conducted with a random sample of 50 general practitioners from ...

  1. Critical Thinking as Miracle Tonic: Selling Snake Oil in Education.

    Science.gov (United States)

    Hyslop-Margison, Emery J.

    This paper proposes that the current interest in critical thinking is based on important conceptual, epistemological, and procedural confusions. It suggests that the attempt to identify a successful critical thinking construct mirrors the search for miracle tonics often peddled by snake oil salesmen as a medicinal cure-all. It goes to suggest that…

  2. Education for Sustainability: A Snakes and Ladders Game?

    Directory of Open Access Journals (Sweden)

    Daniella Tilbury

    2015-07-01

    Full Text Available How to reference this articleTilbury, D. (2015. Education for Sustainability: A Snakes and Ladders Game?. Foro de Educación, 13(19, 7-10. doi: http://dx.doi.org/10.14516/fde.2015.013.019.000

  3. Overview: Birth of the Snake River Plain

    Science.gov (United States)

    Camp, V. E.

    2006-12-01

    The Snake River Plain (SRP) is marked by a linear track of large, age-progressive calderas (Pierce and Morgan, 1992), the youngest of which is underlain by the Yellowstone mantle plume, which extends to a depth of ~500 km at the eastern edge of the province (Yuan and Dueker, 2005). Plate reconstruction to ~16.5 Ma, places the plume near the western edge of the SRP, contemporaneous with the abrupt onset of dike intrusion and flood-basalt magmatism on the Columbia Plateau, the Oregon Plateau, and within the Northern Nevada rift (NNR). Whereas most workers now embrace a plume-related origin for the SRP, others caution against accepting a similar origin for the other three contiguous provinces. This is understandable in light of more traditional models found in the geological literature, combined with the distinctive geology of each province and their locations in a back-arc environment associated with varying degrees of Basin and Range extension. This overview examines the development of ideas on the origin of the SRP and the associated flood-basalts that lie adjacent to its western margin. Often overlooked in the plume vs. nonplume debate is the fact that competing models of Basin and Range extension and plume emplacement are not mutually exclusive. The SRP, Columbia Plateau, Oregon Plateau, and NNR are clearly distinct in their stratigraphy and geological development. As a group, however, they also appear to be intrinsic parts of a single magmatic system, related in both time and space to the Miocene emplacement of the Yellowstone mantle plume into an environment of back-arc extension. The style of volcanism above the plume was manifested in different ways in each province. From ~16.5-15 Ma, an early phase of dike intrusion (NNR) and flood-basalt volcanism (Oregon and Columbia Plateaus) generated the greatest outpouring of continental basalt on Earth over the last 30 million years. This was followed, from ~15 Ma to Present, by a later phase of bimodal volcanism

  4. Australian tiger snake (Notechis scutatus) and mexican coral snake (Micruris species) antivenoms prevent death from United States coral snake (Micrurus fulvius fulvius) venom in a mouse model.

    Science.gov (United States)

    Wisniewski, Michael S; Hill, Robert E; Havey, Joshua M; Bogdan, Gregory M; Dart, Richard C

    2003-01-01

    Wyeth-Ayerst has discontinued production of Antivenin (Micrurus fulvius). Currently, there is no other approved coral snake antivenom available in the United States. This study was a randomized, placebo-controlled and blinded determination of the ability of a Mexican Micrurus (coral snake) antivenom and an Australian Notechis (tiger snake) antivenom to prevent lethality from a United States Micrurus fulvius fulvius venom in a mouse model. Venom dosing was based on an LD50 determined for this experiment. Our comparison groups included: (1) M. f. fulvius venom + Micrurus antivenom, (2) M. f. fulvius venom + Notechis antivenom, (3) M. f. fulvius venom + protein control, (4) 0.9% normal saline + protein control, (5) saline + Notechis antivenom, (6) saline + Micrurus antivenom. Venom dose was 5 times the determined LD50. The antivenom amounts were capable of neutralizing 10 times the venom injected (50 times the LD50). The LD50 of M. f. fulvius venom was determined to be 0.85 mg/kg. All mice in both antivenom test groups were protected from lethality for the entire 24-hour observation period. Six of the 7 mice in the venom test group died, with a survival time of 349 +/- 382 minutes (mean +/- s.d.) after the venom injection. All three groups of control mice survived the entire 24-hour observation period. Mexican Micrurus antivenom and Australian Notechis antivenom provide protection from lethality in mice envenomated with a United States M. f. filvius venom.

  5. Finding the neck-trunk boundary in snakes: anteroposterior dissociation of myological characteristics in snakes and its implications for their neck and trunk body regionalization.

    Science.gov (United States)

    Tsuihiji, Takanobu; Kearney, Maureen; Rieppel, Olivier

    2012-09-01

    The neck and trunk regionalization of the presacral musculoskeletal system in snakes and other limb-reduced squamates was assessed based on observations on craniovertebral and body wall muscles. It was confirmed that myological features characterizing the neck in quadrupedal squamates (i.e., squamates with well-developed limbs) are retained in all examined snakes, contradicting the complete lack of the neck in snakes hypothesized in previous studies. However, the posterior-most origins of the craniovertebral muscles and the anterior-most bony attachments of the body wall muscles that are located at around the neck-trunk boundary in quadrupedal squamates were found to be dissociated anteroposteriorly in snakes. Together with results of a recent study that the anterior expression boundaries of Hox genes coinciding with the neck-trunk boundary in quadrupedal amniotes were dissociated anteroposteriorly in a colubrid snake, these observations support the hypothesis that structures usually associated with the neck-trunk boundary in quadrupedal squamates are displaced relative to one another in snakes. Whereas certain craniovertebral muscles are elongated in some snakes, results of optimization on an ophidian cladogram show that the most recent common ancestor of extant snakes would have had the longest craniovertebral muscle, M. rectus capitis anterior, that is elongated only by several segments compared with that of quadrupedal squamates. Therefore, even such a posteriorly displaced "cervical" characteristic plesiomorphically lies fairly anteriorly in the greatly elongated precloacal region of snakes, suggesting that the trunk, not the neck, would have contributed most to the elongation of the snake precloacal region. A similar dissociation of structures usually associated with the neck-trunk boundary in quadrupedal squamates is observed in limb-reduced squamates, suggesting that these forms and snakes may share a developmental mechanism producing modifications in the

  6. Development of hemipenes in the ball python snake Python regius.

    Science.gov (United States)

    Leal, Francisca; Cohn, Martin J

    2015-01-01

    Within amniotes, external copulatory organs have undergone extensive morphological diversification. One of the most extreme examples is squamate (lizards and snakes) hemipenes, which are paired copulatory organs that extend from the lateral margins of the cloaca. Here, we describe the development of hemipenes in a basal snake, the ball python (Python regius). Snake hemipenes arise as a pair of lateral swellings on either side of the caudal part of the cloaca, and these paired outgrowths persist to form the left and right hemipenes. In non-squamate amniotes, external genitalia form from paired swellings that arise on the anterior side of the cloaca, which then fuse medially to form a single genital tubercle, the anlagen of the penis or clitoris. Whereas in non-squamate amniotes, Sonic hedgehog (Shh)-expressing cells of the cloacal endoderm form the urethral or sulcus epithelium and are required for phallus outgrowth, the hemipenes of squamates lack an endodermal contribution, and the sulcus does not express Shh. Thus, snake hemipenes differ from the genital tubercles of non-squamate amniotes both in their embryonic origins and in at least part of patterning mechanisms, which raises the possibility that hemipenes may not be direct homologs of the unpaired amniote penis. Nonetheless, we find that some developmental genes show similar expression patterns in snake hemipenes buds and non-squamate genital tubercles, suggesting that homologous developmental mechanisms are involved in aspects of external genital development across amniotes, even when these structures may have different developmental origins and may have arisen independently during evolution.

  7. Ontogenetic shifts and spatial associations in organ positions for snakes.

    Science.gov (United States)

    Anderson, Gretchen E; Secor, Stephen M

    2015-12-01

    Snakes possess an elongated body form and serial placement of organs which provides the opportunity to explore historic and adaptive mechanisms of organ position. We examined the influence of body size and sex on the position of, and spatial associations between, the heart, liver, small intestine, and right kidney for ten phylogenetically diverse species of snakes that vary in body shape and habitat. Snake snout-vent length explained much of the variation in the position of these four organs. For all ten species, the position of the heart and liver relative to snout-vent length decreased as a function of size. As body size increased from neonate to adult, these two organs shifted anteriorly an average of 4.7% and 5.7% of snout-vent length, respectively. Similarly, the small intestine and right kidney shifted anteriorly with an increase in snout-vent length for seven and five of the species, respectively. The absolute and relative positioning of these organs did not differ between male and female Burmese pythons (Python molurus). However, for diamondback water snakes (Nerodia rhombifer), the liver and small intestine were more anteriorly positioned in females as compared to males, whereas the right kidney was positioned more anteriorly for males. Correlations of residuals of organ position (deviation from predicted position) demonstrated significant spatial associations between organs for nine of the ten species. For seven species, individuals with hearts more anterior (or posterior) than predicted also tended to possess livers that were similarly anteriorly (or posteriorly) placed. Positive associations between liver and small intestine positions and between small intestine and right kidney positions were observed for six species, while spatial associations between the heart and small intestine, heart and right kidney, and liver and right kidney were observed in three or four species. This study demonstrates that size, sex, and spatial associations may have

  8. Postovipositional development of the sand snake Psammophis sibilans (Serpentes:Lamprophiidae) in comparison with other snake species

    Czech Academy of Sciences Publication Activity Database

    Khannoon, E. R.; Zahradníček, Oldřich

    2017-01-01

    Roč. 98, č. 2 (2017), s. 144-153 ISSN 0001-7272 R&D Projects: GA ČR GB14-37368G Institutional support: RVO:68378041 Keywords : embryonic development * Psammophis * snake Subject RIV: EA - Cell Biology Impact factor: 1.211, year: 2016

  9. Hypernatremia in Dice snakes (Natrix tessellata) from a coastal population: implications for osmoregulation in marine snake prototypes.

    Science.gov (United States)

    Brischoux, François; Kornilev, Yurii V

    2014-01-01

    The widespread relationship between salt excreting structures (e.g., salt glands) and marine life strongly suggests that the ability to regulate salt balance has been crucial during the transition to marine life in tetrapods. Elevated natremia (plasma sodium) recorded in several marine snakes species suggests that the development of a tolerance toward hypernatremia, in addition to salt gland development, has been a critical feature in the evolution of marine snakes. However, data from intermediate stage (species lacking salt glands but occasionally using salty environments) are lacking to draw a comprehensive picture of the evolution of an euryhaline physiology in these organisms. In this study, we assessed natremia of free-ranging Dice snakes (Natrix tessellata, a predominantly fresh water natricine lacking salt glands) from a coastal population in Bulgaria. Our results show that coastal N. tessellata can display hypernatremia (up to 195.5 mmol x l(-1)) without any apparent effect on several physiological and behavioural traits (e.g., hematocrit, body condition, foraging). More generally, a review of natremia in species situated along a continuum of habitat use between fresh- and seawater shows that snake species display a concomitant tolerance toward hypernatremia, even in species lacking salt glands. Collectively, these data suggest that a physiological tolerance toward hypernatremia has been critical during the evolution of an euryhaline physiology, and may well have preceded the evolution of salt glands.

  10. Hypernatremia in Dice snakes (Natrix tessellata from a coastal population: implications for osmoregulation in marine snake prototypes.

    Directory of Open Access Journals (Sweden)

    François Brischoux

    Full Text Available The widespread relationship between salt excreting structures (e.g., salt glands and marine life strongly suggests that the ability to regulate salt balance has been crucial during the transition to marine life in tetrapods. Elevated natremia (plasma sodium recorded in several marine snakes species suggests that the development of a tolerance toward hypernatremia, in addition to salt gland development, has been a critical feature in the evolution of marine snakes. However, data from intermediate stage (species lacking salt glands but occasionally using salty environments are lacking to draw a comprehensive picture of the evolution of an euryhaline physiology in these organisms. In this study, we assessed natremia of free-ranging Dice snakes (Natrix tessellata, a predominantly fresh water natricine lacking salt glands from a coastal population in Bulgaria. Our results show that coastal N. tessellata can display hypernatremia (up to 195.5 mmol x l(-1 without any apparent effect on several physiological and behavioural traits (e.g., hematocrit, body condition, foraging. More generally, a review of natremia in species situated along a continuum of habitat use between fresh- and seawater shows that snake species display a concomitant tolerance toward hypernatremia, even in species lacking salt glands. Collectively, these data suggest that a physiological tolerance toward hypernatremia has been critical during the evolution of an euryhaline physiology, and may well have preceded the evolution of salt glands.

  11. Clinical profile & complications of neurotoxic snake bite & comparison of two regimens of polyvalent anti-snake venom in its treatment

    Directory of Open Access Journals (Sweden)

    Krishna Sarin

    2017-01-01

    Interpretation & conclusions: In this preliminary study, it was found that the national ASV protocol was as effective as the conventional regimen for neurotoxic snake bites. However, the findings need to be tested in a larger randomized controlled trial for definitive conclusions.

  12. Habitat fragmentation effects on annual survival of the federally protected eastern indigo snake

    Science.gov (United States)

    Breininger, D.R.; Mazerolle, M.J.; Bolt, M.R.; Legare, M.L.; Drese, J.H.; Hines, J.E.

    2012-01-01

    The eastern indigo snake (Drymarchon couperi) is a federally listed species, most recently threatened by habitat loss and habitat degradation. In an effort to estimate snake survival, a total of 103 individuals (59 males, 44 females) were followed using radio-tracking from January 1998 to March 2004 in three landscape types that had increasing levels of habitat fragmentation: (1) conservation cores; (2) conservation areas along highways; (3) suburbs. Because of a large number of radio-tracking locations underground for which the state of snakes (i.e. alive or dead) could not be assessed, we employed a multistate approach to model snake apparent survival and encounter probability of live and dead snakes. We predicted that male snakes in suburbs would have the lowest annual survival. We found a transmitter implantation effect on snake encounter probability, as snakes implanted on a given occasion had a lower encounter probability on the next visit compared with snakes not implanted on the previous occasion. Our results indicated that adult eastern indigo snakes have relatively high survival in conservation core areas, but greatly reduced survival in conservation areas along highways and in suburbs. These findings indicate that habitat fragmentation is likely to be the critical factor for species' persistence.

  13. Keeping venomous snakes in the Netherlands: a harmless hobby or a public health threat?

    Science.gov (United States)

    van Genderen, P J J; Slobbe, L; Koene, H; Mastenbroek, R D L; Overbosch, D

    2013-10-01

    To describe the incidence of venomous snakebites and the hospital treatment thereof (if any) amongst private individuals who keep venomous snakes as a hobby. Descriptive study. Private keepers of venomous snakes were invited via the social media Facebook, Hyves, Twitter, Google Plus, Linked In and two large discussion forums to fill in an online questionnaire on a purely voluntary and anonymous basis. In the period from 1 September 2012 to 31 December 2012, 86 questionnaires were completed by individuals who keep venomous snakes as a hobby. One-third of the venomous snake keepers stated that they had at some point been bitten by a venomous snake. Out of those, two-thirds needed hospital treatment and one-third of those bitten required at least one, sometimes more, doses of antiserum. The chances of being bitten increased the more venomous snakes a person kept. An inventory of the collections of venomous snakes being kept further revealed that no antiserum exists for 16 of the species, including for the most commonly held venomous snake, the coral cobra. Keeping venomous snakes as a hobby is not without danger. Although in the majority of snakebite cases no antiserum had to be administered, there is nevertheless a significant risk of morbidity and sequelae. Preventing snakebites in the first place remains the most important safety measure since there are no antiserums available for a substantial number of venomous snakes.

  14. The two faces of Janus, or the dual mode of public attitudes towards snakes.

    Science.gov (United States)

    Liordos, Vasilios; Kontsiotis, Vasileios J; Kokoris, Spyridon; Pimenidou, Michaela

    2018-04-15

    Snakes are controversial animals, therefore a better understanding of public attitudes is critical for their effective protection and future survival. The attitudes towards snakes of 951 adults in Greece were investigated in personal interviews. Factor analysis revealed a dual mode of attitudes: respondents were highly intolerant of snakes, while they supported their conservation at the same time. Respondents had high knowledge about the behavior of snakes, medium knowledge of their biology and were strongly affected by folklore. Structural models revealed that tolerance was a positive mediator of conservation. Knowledge about snake behavior and biology was positively correlated with attitudes towards snakes. Moralistic and naturalistic attitudes were positively, and dominionistic attitudes negatively, correlated with snake tolerance and conservation attitudes. Younger, more educated people were more snake-tolerant than older, less educated people. Females were less snake-tolerant and more conservation-oriented than males. These findings increased the understanding of human attitudes towards snakes and helped identify factors critical for their conservation. As such they could be used to design environmental education programs incorporating both information-based and experiential activities that will improve attitudes, behaviors and, eventually, the chances for the survival of these uncharismatic animals. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. A transitional snake from the Late Cretaceous period of North America.

    Science.gov (United States)

    Longrich, Nicholas R; Bhullar, Bhart-Anjan S; Gauthier, Jacques A

    2012-08-09

    Snakes are the most diverse group of lizards, but their origins and early evolution remain poorly understood owing to a lack of transitional forms. Several major issues remain outstanding, such as whether snakes originated in a marine or terrestrial environment and how their unique feeding mechanism evolved. The Cretaceous Coniophis precedens was among the first Mesozoic snakes discovered, but until now only an isolated vertebra has been described and it has therefore been overlooked in discussions of snake evolution. Here we report on previously undescribed material from this ancient snake, including the maxilla, dentary and additional vertebrae. Coniophis is not an anilioid as previously thought a revised phylogenetic analysis of Ophidia shows that it instead represents the most primitive known snake. Accordingly, its morphology and ecology are critical to understanding snake evolution. Coniophis occurs in a continental floodplain environment, consistent with a terrestrial rather than a marine origin; furthermore, its small size and reduced neural spines indicate fossorial habits, suggesting that snakes evolved from burrowing lizards. The skull is intermediate between that of lizards and snakes. Hooked teeth and an intramandibular joint indicate that Coniophis fed on relatively large, soft-bodied prey. However, the maxilla is firmly united with the skull, indicating an akinetic rostrum. Coniophis therefore represents a transitional snake, combining a snake-like body and a lizard-like head. Subsequent to the evolution of a serpentine body and carnivory, snakes evolved a highly specialized, kinetic skull, which was followed by a major adaptive radiation in the Early Cretaceous period. This pattern suggests that the kinetic skull was a key innovation that permitted the diversification of snakes.

  16. A Study of Clinical Profile of Snake Bite at a Tertiary Care Centre

    Science.gov (United States)

    Bhalla, Gaurav; Mhaskar, Dhanesh; Agarwal, Anubhav

    2014-01-01

    Background: Snake bite is an important occupational and rural hazard because India has always been a land of Exotic snakes. In Maharashtra, common poisonous snakes are Cobra, Russell's Viper, Saw Scaled Viper, and Krait. It is a fact that inspite of heavy morbidity and mortality, very little attention is paid by the clinicians to this occupational hazard. Aims: To study the prevalence of poisonous and non-poisonous snake bites in part of Western Maharashtra with reference to age, sex, occupation, part of body bitten, time of bite and seasonal variation, and the types of poisonous snakes common in this locality and their clinical manifestations along with the systemic envenomation from various types of poisonous snakes and their effective management in reducing the mortality rate. Materials and Methods: This was a retrospective study conducted between May 2010 to May 2012 at a tertiary health care center in Maharashtra. Result: A total of 150 patients were studied in our hospital. Out of 150, 76 patients were of poisonous snake bite and 74 patients were of non-poisonous snake bite. Out of these 76 poisonous snake bites, 42 were viperine snake bites, 21 were neuroparalytic snake bites and 13 were locally toxic (LT) snake bites. Conclusion: Snake bite is a common life-threatening emergency in the study area. Delay in hospitalization is associated with poor prognosis and increased mortality rate due to consumptive coagulopathy, renal failure, and respiratory failure. Unusual complications like pulmonary edema, intracerebral hemorrhage, Disseminated intravascular coagulation (DIC) were observed in present study. PMID:25253932

  17. Predictors of orbital convergence in primates: a test of the snake detection hypothesis of primate evolution.

    Science.gov (United States)

    Wheeler, Brandon C; Bradley, Brenda J; Kamilar, Jason M

    2011-09-01

    Traditional explanations for the evolution of high orbital convergence and stereoscopic vision in primates have focused on how stereopsis might have aided early primates in foraging or locomoting in an arboreal environment. It has recently been suggested that predation risk by constricting snakes was the selective force that favored the evolution of orbital convergence in early primates, and that later exposure to venomous snakes favored further degrees of convergence in anthropoid primates. Our study tests this snake detection hypothesis (SDH) by examining whether orbital convergence among extant primates is indeed associated with the shared evolutionary history with snakes or the risk that snakes pose for a given species. We predicted that orbital convergence would be higher in species that: 1) have a longer history of sympatry with venomous snakes, 2) are likely to encounter snakes more frequently, 3) are less able to detect or deter snakes due to group size effects, and 4) are more likely to be preyed upon by snakes. Results based on phylogenetically independent contrasts do not support the SDH. Orbital convergence shows no relationship to the shared history with venomous snakes, likelihood of encountering snakes, or group size. Moreover, those species less likely to be targeted as prey by snakes show significantly higher values of orbital convergence. Although an improved ability to detect camouflaged snakes, along with other cryptic stimuli, is likely a consequence of increased orbital convergence, this was unlikely to have been the primary selective force favoring the evolution of stereoscopic vision in primates. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Traditional and scientific conceptions of snakes in Kenya: Alternative perspectives for teaching

    Science.gov (United States)

    Wojnowski, David

    A 3-month qualitative study was conducted mid-September through mid-December 2005 to investigate rural southeast Kenyan teachers' conceptions of snakes. Teachers from five villages near Mt. Kasigau were interviewed to obtain an overall sense of what they thought about snakes (n = 60). Of those 60 teachers, 28 attended a 6-hour seminar on reptiles and amphibians. From these 28 teachers, 8 teachers from three villages were afforded additional educational opportunities about snakes, and 2 teachers from this group of 8 were teamed with 2 herpetologists as mentors during the last 2 months of the study. In turn, seven of these eight teachers presented lessons about snakes using live specimens to their fellow teachers and students. Observations of teacher participants during workshops and field outings were documented as well as teacher classroom pedagogy involving snakes before, during, and after the institute. Semi-structured and open-ended interviews were conducted with the eight core teacher participants and field notes were used to document participant observations during serendipitous live snake encounters, of which, there were many. In addition, village elders, including medicine men, one education administrator and one minister were interviewed to obtain a historical cultural backdrop, which teachers expressed as being an important influence while formulating their own conceptions about snakes. Findings suggest that teachers' conceptions of snakes, within a culture where all snakes are feared and killed onsite, can change toward a more favorable orientation when given the opportunity to learn about snakes, witness positive modeling of snake handling through mentoring by herpetologists, and experience direct contact with live harmless nonaggressive snakes (e.g., the Brown House Snake [Lamprohis fuliginosus] and Kenyan Sand Boa [ Eryx colubrinus]).

  19. A preliminary investigations on infective parasites in King rat snakes(Elaphe carinata and Red-banded wolf snakes(Dinodon rufozonatum in Shanghai

    Directory of Open Access Journals (Sweden)

    WU Youling

    2013-12-01

    Full Text Available To investigate the infective status of parasites in snakes from Shanghai,19 snakes from 2 species ( 9 Dinodon rufozonatum and 10 Elaphe carinata confiscated from the market were dissected.The viscera (body,subcutaneous,muscles,heart,lungs,liver,stomach,intestinal organs and blood smears of the snakes were examined.The parasites from these viscera were collected and observed by microscope.The results showed nematodes,tapeworms and Hepatozoon were found,but no ectoparasites,trematodes and acanthocephalan.The parasitic infection rate of snakes checked was 100%.The infection rate of nematodes,tapeworms and Hepatozoon were 77.88%,100%,0 in Dinodon rufozonatum and 100%,100%,100% in Elaphe carinata, respectively.A total of 192 nematodes and 1236 tapeworms were collected in 19 snakes,and 69.79% of nematodes and 86.55% of tapeworms were from Elaphe carinata.According to the viscera,93.20% of tapeworms were found in subcutaneous and 65.63% of nematodes in stomach.The results indicated the parasitic infection rate and intensity of snakes from Shanghai market were very high.Sparganum mansoni found in this investigation was zoonotic parasite,and it is easy to infect humans through eating snake skin,meat and gall.Therefore,protecting wild animals like snakes is also to protect human themselves.

  20. Distribution and outcome of ocular lesions in snakes examined at a veterinary teaching hospital: 67 cases (1985-2010).

    Science.gov (United States)

    Hausmann, Jennifer C; Hollingsworth, Steven R; Hawkins, Michelle G; Kass, Philip H; Maggs, David J

    2013-07-15

    To determine the distribution and clinical outcome of ocular lesions in snakes. Retrospective case series. 67 snakes with ocular lesions. Signalment, lesion duration, diagnosis, treatment, and clinical outcome were recorded for all snakes with ocular lesions that were examined at a veterinary teaching hospital from 1985 to 2010. 71 ocular lesions were detected in 67 of 508 (13%) snakes examined. Affected snakes were of the families Boidae, Pythonidae, Colubridae, and Viperidae. The distribution of ocular lesions did not vary by taxonomic family, age, or sex; however, snakes from the genus Epicrates with ocular lesions were overrepresented in the population. The most commonly diagnosed ocular lesions were retained spectacle (n = 41), pseudobuphthalmos or subspectacular abscess (13), trauma (8), and cataracts (4). Pseudobuphthalmos or subspectacular abscess developed more frequently in Colubridae than in non-Colubridae snakes. Of the 16 snakes with retained spectacles for which data were available, the lesion recurred once in 4 snakes and multiple times in 5 snakes. Results indicated that retained spectacle was the most common ocular lesion diagnosed in snakes. Compared with other snakes with ocular lesions, snakes of the genus Epicrates had a higher than expected frequency of ocular lesions in general and snakes of the family Colubridae had a higher than expected frequency of pseudobuphthalmos or subspectacular abscess.

  1. Snake River Fall Chinook Salmon life history investigations

    Science.gov (United States)

    Erhardt, John M.; Bickford, Brad; Hemingway, Rulon J.; Rhodes, Tobyn N.; Tiffan, Kenneth F.

    2017-01-01

    Predation by nonnative fishes is one factor that has been implicated in the decline of juvenile salmonids in the Pacific Northwest. Impoundment of much of the Snake and Columbia rivers has altered food webs and created habitat favorable for species such as Smallmouth Bass Micropterus dolomieu. Smallmouth Bass are common throughout the Columbia River basin and have become the most abundant predator in lower Snake River reservoirs (Zimmerman and Parker 1995). This is a concern for Snake River Fall Chinook Salmon Oncorhynchus tshawytscha (hereafter, subyearlings) that may be particularly vulnerable due to their relatively small size and because their main-stem rearing habitats often overlap or are in close proximity to habitats used by Smallmouth Bass (Curet 1993; Tabor et al. 1993). Concern over juvenile salmon predation spawned a number of large-scale studies to quantify its effect in the late 1980s, 1990s, and early 2000s (Poe et al. 1991; Rieman et al. 1991; Vigg et al. 1991; Fritts and Pearsons 2004; Naughton et al. 2004). Smallmouth Bass predation represented 9% of total salmon consumption by predatory fishes in John Day Reservoir, Columbia River, from 1983 through 1986 (Rieman et al. 1991). In transitional habitat between the Hanford Reach of the Columbia River and McNary Reservoir, juvenile salmon (presumably subyearlings) were found in 65% of Smallmouth Bass (>200 mm) stomachs and comprised 59% of the diet by weight (Tabor et al. 1993). Within Lower Granite Reservoir on the Snake River, Naughton et al. (2004) showed that monthly consumption (based on weight) ranged from 5% in the upper reaches of the reservoir to 11% in the forebay. However, studies in the Snake River were conducted soon after Endangered Species Act (ESA) listing of Snake River Fall Chinook Salmon (NMFS 1992). During this time, Fall Chinook Salmon abundance was at an historic low, which may explain why consumption rates were relatively low compared to those from studies conducted in the

  2. Design of a new therapy to treat snake envenomation

    Directory of Open Access Journals (Sweden)

    Shahidi Bonjar L

    2014-06-01

    Full Text Available Leyla Shahidi BonjarDepartment of Pharmacology, College of Pharmacy, Kerman University of Medical Sciences, International Campus, Kerman, IranAbstract: The prospective removal of snake venoms from the blood of snake-bitten patients is discussed here. Opportune neutralization of killer antigens from the blood of poisoned victims is a vital treatment step. Delays may lead to death, or cripple the patient permanently. The present procedure describes the elimination of venom antigens of a wide range of snakes from the blood of such patients. Compared to conventional treatments, the treatment is administrable in the lack of proper antivenoms, expected to be more effective with less side effects, covers a vast range of snake venoms, minimizes contact of venoms with internal tissues and organs, is applicable in patients sensitive to serum injections, has a high chance of effectiveness because there is no need to identity the snake involved to administer its specific antibody, and is capable of universal application. The principal component to this approach is a “polyvalent venom antibody column” (PVAC, which selectively traps venom antigens from blood in an extracorporeal circuit while detoxified blood returns back to the patient's body. The PVAC is intended for removal of numerous snake venom antigens in a relatively simple procedure. Detoxification is performed under the supervision of trained personnel using simple blood-circulating machines in which blood circulates from patient to PVAC and back to the patient aseptically. The device acts as a biological filter that selectively immobilizes harmful venom antigens from poisoned blood. For effective neutralization, the PVAC provides a large contact surface area with blood. The PVAC’s reactive sites would consist of carbon nanotubes, on which a vast spectra of venoms' antibodies are bonded to. In this extracorporeal detoxification process, nocent antigens conjugate with their antibodies and

  3. Snake venomics and venom gland transcriptomic analysis of Brazilian coral snakes, Micrurus altirostris and M. corallinus.

    Science.gov (United States)

    Corrêa-Netto, Carlos; Junqueira-de-Azevedo, Inácio de L M; Silva, Débora A; Ho, Paulo L; Leitão-de-Araújo, Moema; Alves, Maria Lúcia M; Sanz, Libia; Foguel, Débora; Zingali, Russolina Benedeta; Calvete, Juan J

    2011-08-24

    The venom proteomes of Micrurus altirostris and M. corallinus were analyzed by combining snake venomics and venom gland transcriptomic surveys. In both coral snake species, 3FTx and PLA(2) were the most abundant and diversified toxin families. 33 different 3FTxs and 13 PLA(2) proteins, accounting respectively for 79.5% and 13.7% of the total proteins, were identified in the venom of M. altirostris. The venom of M. corallinus comprised 10 3FTx (81.7% of the venom proteome) and 4 (11.9%) PLA(2) molecules. Transcriptomic data provided the full-length amino acid sequences of 18 (M. altirostris) and 10 (M. corallinus) 3FTxs, and 3 (M. altirostris) and 1 (M. corallinus) novel PLA(2) sequences. In addition, venom from each species contained single members of minor toxin families: 3 common (PIII-SVMP, C-type lectin-like, L-amino acid oxidase) and 4 species-specific (CRISP, Kunitz-type inhibitor, lysosomal acid lipase in M. altirostris; serine proteinase in M. corallinus) toxin classes. The finding of a lipase (LIPA) in the venom proteome and in the venom gland transcriptome of M. altirostris supports the view of a recruitment event predating the divergence of Elapidae and Viperidae more than 60 Mya. The toxin profile of both M. altirostris and M. corallinus venoms points to 3FTxs and PLA(2) molecules as the major players of the envenoming process. In M. altirostris venom, all major, and most minor, 3FTxs display highest similarity to type I α-neurotoxins, suggesting that these postsynaptically acting toxins may play the predominant role in the neurotoxic effect leading to peripheral paralysis, respiratory arrest, and death. M. corallinus venom posesses both, type I α-neurotoxins and a high-abundance (26% of the venom proteome) protein of subfamily XIX of 3FTxs, exhibiting similarity to bucandin from Malayan krait, Bungarus candidus, venom, which enhances acetylcholine release presynaptically. This finding may explain the presynaptic neurotoxicity of M. corallinus venom

  4. Venom Down Under: Dynamic Evolution of Australian Elapid Snake Toxins

    Science.gov (United States)

    Jackson, Timothy N. W.; Sunagar, Kartik; Undheim, Eivind A. B.; Koludarov, Ivan; Chan, Angelo H. C.; Sanders, Kate; Ali, Syed A.; Hendrikx, Iwan; Dunstan, Nathan; Fry, Bryan G.

    2013-01-01

    Despite the unparalleled diversity of venomous snakes in Australia, research has concentrated on a handful of medically significant species and even of these very few toxins have been fully sequenced. In this study, venom gland transcriptomes were sequenced from eleven species of small Australian elapid snakes, from eleven genera, spanning a broad phylogenetic range. The particularly large number of sequences obtained for three-finger toxin (3FTx) peptides allowed for robust reconstructions of their dynamic molecular evolutionary histories. We demonstrated that each species preferentially favoured different types of α-neurotoxic 3FTx, probably as a result of differing feeding ecologies. The three forms of α-neurotoxin [Type I (also known as (aka): short-chain), Type II (aka: long-chain) and Type III] not only adopted differential rates of evolution, but have also conserved a diversity of residues, presumably to potentiate prey-specific toxicity. Despite these differences, the different α-neurotoxin types were shown to accumulate mutations in similar regions of the protein, largely in the loops and structurally unimportant regions, highlighting the significant role of focal mutagenesis. We theorize that this phenomenon not only affects toxin potency or specificity, but also generates necessary variation for preventing/delaying prey animals from acquiring venom-resistance. This study also recovered the first full-length sequences for multimeric phospholipase A2 (PLA2) ‘taipoxin/paradoxin’ subunits from non-Oxyuranus species, confirming the early recruitment of this extremely potent neurotoxin complex to the venom arsenal of Australian elapid snakes. We also recovered the first natriuretic peptides from an elapid that lack the derived C-terminal tail and resemble the plesiotypic form (ancestral character state) found in viper venoms. This provides supporting evidence for a single early recruitment of natriuretic peptides into snake venoms. Novel forms of kunitz

  5. Venom Down Under: Dynamic Evolution of Australian Elapid Snake Toxins

    Directory of Open Access Journals (Sweden)

    Timothy N. W. Jackson

    2013-12-01

    Full Text Available Despite the unparalleled diversity of venomous snakes in Australia, research has concentrated on a handful of medically significant species and even of these very few toxins have been fully sequenced. In this study, venom gland transcriptomes were sequenced from eleven species of small Australian elapid snakes, from eleven genera, spanning a broad phylogenetic range. The particularly large number of sequences obtained for three-finger toxin (3FTx peptides allowed for robust reconstructions of their dynamic molecular evolutionary histories. We demonstrated that each species preferentially favoured different types of α-neurotoxic 3FTx, probably as a result of differing feeding ecologies. The three forms of α-neurotoxin [Type I (also known as (aka: short-chain, Type II (aka: long-chain and Type III] not only adopted differential rates of evolution, but have also conserved a diversity of residues, presumably to potentiate prey-specific toxicity. Despite these differences, the different α-neurotoxin types were shown to accumulate mutations in similar regions of the protein, largely in the loops and structurally unimportant regions, highlighting the significant role of focal mutagenesis. We theorize that this phenomenon not only affects toxin potency or specificity, but also generates necessary variation for preventing/delaying prey animals from acquiring venom-resistance. This study also recovered the first full-length sequences for multimeric phospholipase A2 (PLA2 ‘taipoxin/paradoxin’ subunits from non-Oxyuranus species, confirming the early recruitment of this extremely potent neurotoxin complex to the venom arsenal of Australian elapid snakes. We also recovered the first natriuretic peptides from an elapid that lack the derived C-terminal tail and resemble the plesiotypic form (ancestral character state found in viper venoms. This provides supporting evidence for a single early recruitment of natriuretic peptides into snake venoms. Novel

  6. Pulvinar neurons reveal neurobiological evidence of past selection for rapid detection of snakes.

    Science.gov (United States)

    Van Le, Quan; Isbell, Lynne A; Matsumoto, Jumpei; Nguyen, Minh; Hori, Etsuro; Maior, Rafael S; Tomaz, Carlos; Tran, Anh Hai; Ono, Taketoshi; Nishijo, Hisao

    2013-11-19

    Snakes and their relationships with humans and other primates have attracted broad attention from multiple fields of study, but not, surprisingly, from neuroscience, despite the involvement of the visual system and strong behavioral and physiological evidence that humans and other primates can detect snakes faster than innocuous objects. Here, we report the existence of neurons in the primate medial and dorsolateral pulvinar that respond selectively to visual images of snakes. Compared with three other categories of stimuli (monkey faces, monkey hands, and geometrical shapes), snakes elicited the strongest, fastest responses, and the responses were not reduced by low spatial filtering. These findings integrate neuroscience with evolutionary biology, anthropology, psychology, herpetology, and primatology by identifying a neurobiological basis for primates' heightened visual sensitivity to snakes, and adding a crucial component to the growing evolutionary perspective that snakes have long shaped our primate lineage.

  7. Pulvinar neurons reveal neurobiological evidence of past selection for rapid detection of snakes

    Science.gov (United States)

    Van Le, Quan; Isbell, Lynne A.; Matsumoto, Jumpei; Nguyen, Minh; Hori, Etsuro; Maior, Rafael S.; Tomaz, Carlos; Tran, Anh Hai; Ono, Taketoshi; Nishijo, Hisao

    2013-01-01

    Snakes and their relationships with humans and other primates have attracted broad attention from multiple fields of study, but not, surprisingly, from neuroscience, despite the involvement of the visual system and strong behavioral and physiological evidence that humans and other primates can detect snakes faster than innocuous objects. Here, we report the existence of neurons in the primate medial and dorsolateral pulvinar that respond selectively to visual images of snakes. Compared with three other categories of stimuli (monkey faces, monkey hands, and geometrical shapes), snakes elicited the strongest, fastest responses, and the responses were not reduced by low spatial filtering. These findings integrate neuroscience with evolutionary biology, anthropology, psychology, herpetology, and primatology by identifying a neurobiological basis for primates’ heightened visual sensitivity to snakes, and adding a crucial component to the growing evolutionary perspective that snakes have long shaped our primate lineage. PMID:24167268

  8. The diets of Hispaniolan colubrid snakes : I. Introduction and prey genera.

    Science.gov (United States)

    Henderson, Robert W

    1984-05-01

    Approximately 1590 Hispaniolan colubrid snakes representing six genera and eight species were examined for prey remains (Alsophis cantherigerus, Antillophis parvifrons, Darlingtonia haetiana, Hypsirhynchus ferox, Ialtris dorsalis, Uromacer catesbyi, U. frenatus, and U. oxyrhynchus). The snakes were collected at many localities over a span of 80 years.Of 426 prey items, 77.9% were lizards (of which 69.6% were anoles), 19% frogs, 2.6% birds and mammals, and 0.5% other snakes. Darlingtonia was the only snake that did not exploit lizards; it fed exclusively on Eleutherodactylus frogs, including egg clutches. Disregarding Darlingtonia, there is no size class of Hispaniolan colubrids between 20-90 cm SVL that does not prey primarily on Anolis. Certain prey genera are added to, or deleted from, diets depending on snake size, but the data suggest that snake SVL alone does little to dictate what prey genera (or groups) are eaten. Shannon-Wiener values (H') indicate that Darlingtonia has the narrowest trophic niche, while Alsophis and Ialtris have the widest. Values of H' are not correlated with snake SVL, but highly significant (Psnake species grow larger, anoles play a decreasingly important role in their diets, there is no evidence to suggest that they are ever abandoned as a food source by any Hispaniolan colubrid of any size.Secretive lizards of low vagility are eaten almost exclusively by wide ranging foragers (Alsophis, Antillophis); very active prey (Ameiva) is taken by sit-and-wait strategists (Hysirhynchus, U. frenatus). Those snakes which exploit the most prey groups are active foragers. Uromacer catesbyi exhibits both foraging modes, and predictably, eats diurnally active (anoles) and diurnally quiescent (hylid frogs) prey with almost equal frequency.Within Maglio's cantherigerus species assemblage, in which an Alsophis cantherigerus-like snake was ancestral to the other species, and in which longsnouted Uromacer are the most morphologically derived, there is an

  9. Detection of eastern equine encephalomyelitis virus RNA in North American snakes.

    Science.gov (United States)

    Bingham, Andrea M; Graham, Sean P; Burkett-Cadena, Nathan D; White, Gregory S; Hassan, Hassan K; Unnasch, Thomas R

    2012-12-01

    The role of non-avian vertebrates in the ecology of eastern equine encephalomyelitis virus (EEEV) is unresolved, but mounting evidence supports a potential role for snakes in the EEEV transmission cycle, especially as over-wintering hosts. To determine rates of exposure and infection, we examined serum samples from wild snakes at a focus of EEEV in Alabama for viral RNA using quantitative reverse transcription polymerase chain reaction. Two species of vipers, the copperhead (Agkistrodon contortrix) and the cottonmouth (Agkistrodon piscivorus), were found to be positive for EEEV RNA using this assay. Prevalence of EEEV RNA was more frequent in seropositive snakes than seronegative snakes. Positivity for the quantitative reverse transcription polymerase chain reaction in cottonmouths peaked in April and September. Body size and sex ratios were not significantly different between infected and uninfected snakes. These results support the hypothesis that snakes are involved in the ecology of EEEV in North America, possibly as over-wintering hosts for the virus.

  10. Postmortem examination of Australian sea snakes ( Hydrophiinae): Anatomy and common pathologic conditions.

    Science.gov (United States)

    Gillett, Amber K; Ploeg, Richard; Flint, Mark; Mills, Paul C

    2017-09-01

    There is limited published information about disease in wild sea snakes and no standardized guideline for postmortem examination of sea snakes. Identifying causes of morbidity and mortality of marine vertebrate species has been pivotal to understanding disease factors implicated in stranding events and assisting with the formulation of conservation plans. Additionally, postmortem findings can provide valuable information on life history traits and the ecology of these reclusive species. Sick, moribund, or dead sea snakes are intermittently washed ashore along Australian and international beaches and provide an opportunity to examine a subset of the population and identify causes of population decline. We present an illustrated description of sea snake anatomy and describe a systematic approach to postmortem examination of sea snakes. We describe common pathologic conditions identified from clinical and postmortem examinations of stranded Australian sea snakes from southeast Queensland. Notable pathologic conditions include traumatic injury, inflammatory conditions, parasitic infections, and neoplasia.

  11. Biogeographic origins of the viviparous sea snake assemblage (Elapidae) of the Indian Ocean

    DEFF Research Database (Denmark)

    Ukuwela, D P; Lee, Michael S. Y.; Redsted Rasmussen, Arne

    2017-01-01

    Abstract: One of the primary goals in biogeography is to understand how different biotas have been assembled in different regions of the world. The presence of the viviparous sea snakes in the Indian Ocean (IO) poses a unique question in this regard due to their evolutionary origins in Australasia...... (Australia and New Guinea). Here, we examined the origins and patterns of colonization of the IO sea snake assemblage through time-calibrated molecular phylogenies and ancestral area reconstructions. We further evaluated how past and present barriers to dispersal affect genetic diversity of IO sea snakes...... by examining the population genetic structure of the widespread sea snake, Hydrophis curtus. Our phylogenetic analyses and ancestral area reconstructions strongly indicate that the majority of the IO sea snakes are derived from the Southeast Asian (SEA) sea snake fauna through dispersal and colonization...

  12. NEUTRALIZATION OF TWO NORTH AMERICAN CORAL SNAKE VENOMS WITH UNITED STATES AND MEXICAN ANTIVENOMS

    OpenAIRE

    Sánchez, Elda E.; Lopez-Johnston, Juan C.; Rodríguez-Acosta, Alexis; Pérez, John C.

    2007-01-01

    Elapid snakes throughout the world are considered very lethal containing neurotoxic venoms that affect the nervous system. When humans are envenomated it is considered a serious medical emergency, and antivenom is the main form of treatment considered, in spite of the fact that some patients may only survive under intensive therapy treatment such as respiratory support. Coral snakes are part of the family Elapidae and envenomations by these snakes are very low (< 2% of total snakebites) in mo...

  13. Decline in sea snake abundance on a protected coral reef system in the New Caledonian Lagoon

    Science.gov (United States)

    Goiran, C.; Shine, R.

    2013-03-01

    Monitoring results from a small reef (Ile aux Canards) near Noumea in the New Caledonian Lagoon reveal that numbers of turtle-headed sea snakes ( Emydocephalus annulatus) have been in consistent decline over a 9-year period, with average daily counts of snakes decreasing from >6 to snake populations to check whether the declines now documented for New Caledonia and in nearby Australian waters also occur around the islands of the Indo-Pacific.

  14. Neutralization of two North American coral snake venoms with United States and Mexican antivenoms.

    Science.gov (United States)

    Sánchez, Elda E; Lopez-Johnston, Juan C; Rodríguez-Acosta, Alexis; Pérez, John C

    2008-02-01

    Elapid snakes throughout the world are considered very lethal, containing neurotoxic venoms that affect the nervous system. When humans are envenomated it is considered a serious medical emergency, and antivenom is the main form of treatment considered, in spite of the fact that some patients may only survive under intensive therapy treatment such as respiratory support. Coral snakes are part of the family Elapidae and envenomations by these snakes are very low (coral snakes of medical importance that belong to the Micrurus genera: Micrurus fulvius fulvius (Eastern coral snake) and Micrurus tener tener (Texas coral snake). In 2006, Wyeth pharmaceutical notified customers that the production of the North American coral snake antivenin (NACSA) in the US was discontinued and adequate supplies were available to meet historical needs through the end of October 2008; and therefore, it is of utmost important to consider other antivenoms as alternatives for the treatment of coral snake envenoming. One logical alternative is the coral snake antivenom, Coralmyn, produced by the Mexican company, Bioclon. In order to compare neutralization between NACSA and Coralmyn antivenoms with the North American coral snake venoms, the venom lethal doses (LD(50)) and antivenom effective doses (ED(50)) were determined in 18-20 g, female, BALB/c mice. Additionally, venom comparisons were determined through a non-reduced SDS-PAGE for M.f.fulvius, M.t.tener and the Mexican coral snake venom, Micrurus nigrocinctus nigrocinctus. Coralmyn antivenom was able to effectively neutralize three LD(50) doses of all venom from both M.t.tener and M.f.fulvius, while Wyeth antivenom only neutralized M.f.fulvius venom and was not effective in neutralizing three LD(50) doses of M.t.tener venom. Coralmyn is effective in the neutralization of both clinically important coral snake venoms in the US.

  15. Predation upon hatchling dinosaurs by a new snake from the late Cretaceous of India.

    Directory of Open Access Journals (Sweden)

    Jeffrey A Wilson

    2010-03-01

    Full Text Available Derived large-mouthed snakes (macrostomatans possess numerous specializations in their skull and lower jaws that allow them to consume large vertebrate prey. In contrast, basal snakes lack these adaptations and feed primarily on small prey items. The sequence of osteological and behavioral modifications involved in the evolution of the macrostomatan condition has remained an open question because of disagreement about the origin and interrelationships of snakes, the paucity of well-preserved early snake fossils on many continental landmasses, and the lack of information about the feeding ecology of early snakes. We report on a partial skeleton of a new 3.5-m-long snake, Sanajeh indicus gen. et sp. nov., recovered from Upper Cretaceous rocks of western India. S. indicus was fossilized in association with a sauropod dinosaur egg clutch, coiled around an egg and adjacent to the remains of a ca. 0.5-m-long hatchling. Multiple snake-egg associations at the site strongly suggest that S. indicus frequented nesting grounds and preyed on hatchling sauropods. We interpret this pattern as "ethofossil" preservation of feeding behavior. S. indicus lacks specializations of modern egg-eaters and of macrostomatans, and skull and vertebral synapomorphies place it in an intermediate position in snake phylogeny. Sanajeh and its large-bodied madtsoiid sister taxa Yurlunggur camfieldensis and Wonambi naracoortensis from the Neogene of Australia show specializations for intraoral prey transport but lack the adaptations for wide gape that characterize living macrostomatan snakes. The Dholi Dungri fossils are the second definitive association between sauropod eggs and embryonic or hatchling remains. New fossils from western India provide direct evidence of feeding ecology in a Mesozoic snake and demonstrate predation risks for hatchling sauropod dinosaurs. Our results suggest that large body size and jaw mobility afforded some non-macrostomatan snakes a greater

  16. Prevalence and intensity of pentastomid infection in two species of snakes from northeastern Brazil

    OpenAIRE

    WO. Almeida; Vasconcellos,A.; SG. Lopes; EMX. Freire

    2007-01-01

    This study aimed to evaluate the infection rates of snakes by pentastomids in the semi-arid region of Brazil. Fifteen snakes (four Micrurus ibiboboca (Merrem, 1820) and eleven Philodryas nattereri Steindachner, 1870) were collected between January and April of 2005, in the municipality of Crato (07° 14' S and 39° 24' W), State of Ceará, Brazil. Laboratorial analysis of the respiratory tracts of the sampled snakes indicated differences in host infection rates: four individuals of P. na...

  17. A case study of Megaselia scalaris (Diptera: Phoridae) causing ocular myiasis in a western hognose snake.

    Science.gov (United States)

    Diclaro, J W; Lehnert, M S; Mitola, M A; Pereira, R M; Koehler, P G

    2011-07-01

    Late instar larvae of the scuttle fly, Megaselia scalaris Loew, were found near the right eye of a live captive-reared western hognose snake, Heterodon nasicus Baird and Girard. Dissection and removal of the snake's dorsal cranial bones revealed tissue degradation of the infected eye, the optic nerve, and the brain case; we suggest that these factors contributed to the death of this snake. This case study further demonstrates the opportunistic behavior of M. scalaris.

  18. The king cobra genome reveals dynamic gene evolution and adaptation in the snake venom system

    OpenAIRE

    Vonk, F.J.; Casewell, N. R.; Henkel, C.V.; Heimberg, A. M.; Jansen, H.J.; McCleary, R.J.R.; Kerkkamp, H. M. E.; Vos, R. A.; Guerreiro, I.; Calvete, J. J.; Wüster, W; Woods, A E; Logan, J. M.; Harrison, R. A.; Castoe, T. A.

    2013-01-01

    Snakes are limbless predators, and many species use venom to help overpower relatively large, agile prey. Snake venoms are complex protein mixtures encoded by several multilocus gene families that function synergistically to cause incapacitation. To examine venom evolution, we sequenced and interrogated the genome of a venomous snake, the king cobra (Ophiophagus hannah), and compared it, together with our unique transcriptome, microRNA, and proteome datasets from this species, with data from ...

  19. Adaptive Evolution and Functional Redesign of Core Metabolic Proteins in Snakes

    OpenAIRE

    Castoe, Todd A.; Jiang, Zhi J.; Wanjun Gu; Wang, Zhengyuan O.; Pollock, David D.

    2008-01-01

    BACKGROUND: Adaptive evolutionary episodes in core metabolic proteins are uncommon, and are even more rarely linked to major macroevolutionary shifts. METHODOLOGY/PRINCIPAL FINDINGS: We conducted extensive molecular evolutionary analyses on snake mitochondrial proteins and discovered multiple lines of evidence suggesting that the proteins at the core of aerobic metabolism in snakes have undergone remarkably large episodic bursts of adaptive change. We show that snake mitochondrial proteins ex...

  20. Abundance and species richness of snakes along the Middle Rio Grande riparian forest in New Mexico

    Science.gov (United States)

    Heather L. Bateman; Alice Chung-MacCoubrey; Howard L. Snell; Deborah M. Finch

    2009-01-01

    To understand the effects of removal of non-native plants and fuels on wildlife in the riparian forest of the Middle Rio Grande in New Mexico, we monitored snakes from 2000 to 2006 using trap arrays of drift fences, pitfalls, and funnel traps. We recorded 158 captures of 13 species of snakes from 12 study sites. We captured more snakes in funnel traps than in pitfalls...

  1. Students’ attitudes toward and knowledge about snakes in the semiarid region of Northeastern Brazil

    OpenAIRE

    Alves, Rômulo RN; Silva, Vanessa N; Trovão, Dilma MBM; Oliveira, José V; Mourão, José S; Dias, Thelma LP; Alves, Ângelo GC; Lucena, Reinaldo FP; Barboza, Raynner RD; Montenegro, Paulo FGP; Vieira, Washington LS; Souto, Wedson MS

    2014-01-01

    Background Humans in various cultures have feared snakes, provoking an aversion and persecution that hinders conservation efforts for these reptiles. Such fact suggests that conservation strategies for snakes should consider the interactions and perceptions of the local population towards these animals. The aim of this study was to investigate students' perception of snakes and if attitudes and knowledge may differ according to gender and local residence (urban or rural). Methods Data was col...

  2. Predation upon hatchling dinosaurs by a new snake from the late Cretaceous of India.

    Science.gov (United States)

    Wilson, Jeffrey A; Mohabey, Dhananjay M; Peters, Shanan E; Head, Jason J

    2010-03-02

    Derived large-mouthed snakes (macrostomatans) possess numerous specializations in their skull and lower jaws that allow them to consume large vertebrate prey. In contrast, basal snakes lack these adaptations and feed primarily on small prey items. The sequence of osteological and behavioral modifications involved in the evolution of the macrostomatan condition has remained an open question because of disagreement about the origin and interrelationships of snakes, the paucity of well-preserved early snake fossils on many continental landmasses, and the lack of information about the feeding ecology of early snakes. We report on a partial skeleton of a new 3.5-m-long snake, Sanajeh indicus gen. et sp. nov., recovered from Upper Cretaceous rocks of western India. S. indicus was fossilized in association with a sauropod dinosaur egg clutch, coiled around an egg and adjacent to the remains of a ca. 0.5-m-long hatchling. Multiple snake-egg associations at the site strongly suggest that S. indicus frequented nesting grounds and preyed on hatchling sauropods. We interpret this pattern as "ethofossil" preservation of feeding behavior. S. indicus lacks specializations of modern egg-eaters and of macrostomatans, and skull and vertebral synapomorphies place it in an intermediate position in snake phylogeny. Sanajeh and its large-bodied madtsoiid sister taxa Yurlunggur camfieldensis and Wonambi naracoortensis from the Neogene of Australia show specializations for intraoral prey transport but lack the adaptations for wide gape that characterize living macrostomatan snakes. The Dholi Dungri fossils are the second definitive association between sauropod eggs and embryonic or hatchling remains. New fossils from western India provide direct evidence of feeding ecology in a Mesozoic snake and demonstrate predation risks for hatchling sauropod dinosaurs. Our results suggest that large body size and jaw mobility afforded some non-macrostomatan snakes a greater diversity of prey items

  3. Snake-like chromatin in conjunctival cells of normal elderly persons and of patients with primary Sjögren's syndrome and other connective tissue diseases

    DEFF Research Database (Denmark)

    Bjerrum, Kirsten Birgitte

    1995-01-01

    Ophthalmology, snake-like chromatin, cytoplasm ratio, keratoconjunctivitis sicca, nucleus, goblet cell......Ophthalmology, snake-like chromatin, cytoplasm ratio, keratoconjunctivitis sicca, nucleus, goblet cell...

  4. Human, snake, and environmental factors in human-snake conflict in North Bihar — a one-year descriptive study.

    Directory of Open Access Journals (Sweden)

    Takanungsang Longkumer

    2016-01-01

    Full Text Available Background: The state of Bihar has the third largest number of snakebite deaths in India. The purpose of this study is to explore the factors related to human-snake conflicts in northwest Bihar and southern Nepal. Using these findings, various strategies were proposed to reduce the incidence of snakebites. Method: Data were collected from 609 patients at Duncan Hospital in Raxaul, Bihar, India between 1 July 2012 and 30 June 2013. Patients were included if they had a history of snakebite or unknown bites. Patients with symptoms of envenomation but no known bites were also included, as were patients who were dead on arrival due to a snakebite. Results: The 10-19 year old age group is the peak age group (28.4% for snakebite. There is a slight preponderance of males (52.7%. 51.4% of bites occurred on the foot/ankle. The envenomation rate was 12.6%. The mortality rate of those envenomed that arrived at the hospital alive was 6.3%. Fourteen people were dead on arrival at the hospital.75% of people were unable to identify what, or what type of snake, bit them. Common Wolf Snakes (Lycodon aulicus were the most common snakes brought to the hospital, followed by Spectacled Cobra (Naja naja. Patients who brought snakes to the hospital and attempted identification were all successful at identifying cobras, but all those who brought in Common Wolf Snakes incorrectly identified them as Kraits. The highest monthly frequency of snakebites occurred between June and September; while on a daily basis, the highest frequency occurred between 1700hrs-2200hrs, the time in which 39.1% of all bites occurred.59.2% of the bites occurred in and around the house. Farming, housework, sleeping, playing, and toileting in fields were the activities most commonly occurring when bitten. Sleeping on the floor increased the risk of envenomation [OR= 5.8, 95%CI 1.8-18.6], while sleeping under a mosquito net decreased the risk of envenomation [OR= 0.17, 95%CI 0.04-0.6]. Conclusion

  5. Acute barium toxicity from ingestion of "snake" fireworks.

    Science.gov (United States)

    Rhyee, Sean H; Heard, Kennon

    2009-12-01

    Ingestion of fireworks has been infrequently reported in the medical literature. We describe a case of acute barium poisoning following firework ingestion. A 35-year-old male with a history of severe mental retardation presented with vomiting and diarrhea following ingestion of 16 small fireworks ("color snakes" and "black snakes"). His condition rapidly deteriorated and he developed obtundation, wide complex dysrhythmias, and respiratory failure. Approximately 12 hours following ingestion, his serum potassium level was 1.5 mmol/L with a serum barium level of 20,200 microg/mL (reference range firework ingestion is uncommon, clinicians should be prepared for potentially severe complications. In the case of barium poisoning, treatment consists of potassium supplementation, along with respiratory and hemodynamic support.

  6. Actions of snake neurotoxins on an insect nicotinic cholinergic synapse.

    Science.gov (United States)

    Hue, Bernard; Buckingham, Steven D; Buckingham, David; Sattelle, David B

    2007-09-01

    Here we examine the actions of six snake neurotoxins (alpha-cobratoxin from Naja naja siamensis, erabutoxin-a and b from Laticauda semifasciata; CM12 from N. haje annulifera, toxin III 4 from Notechis scutatus and a long toxin from N. haje) on nicotinic acetylcholine receptors in the cercal afferent, giant interneuron 2 synapse of the cockroach, Periplaneta americana. All toxins tested reduced responses to directly-applied ACh as well as EPSPs evoked by electrical stimulation of nerve XI with similar time courses, suggesting that their action is postsynaptic. Thus, these nicotinic receptors in a well-characterized insect synapse are sensitive to both long and short chain neurotoxins. This considerably expands the range of snake toxins that block insect nicotinic acetylcholine receptors and may enable further pharmacological distinctions between nAChR subtypes.

  7. Design study of a normal conducting helical snake for AGS

    CERN Document Server

    Takano, Junpei; Okamura, Masahiro; Roser, Thomas; MacKay, William W; Luccio, Alfredo U; Takano, Koji

    2004-01-01

    A new normal conducting snake magnet is being fabricated for the Alternate Gradient Synchrotron (AGS) at Brookhaven National Laboratory (BNL). In the Relativistic Heavy Ion Collider (RHIC) project, a superconducting type helical dipole magnets had been developed and it performed successfully in high-energy polarized proton acceleration. The new AGS helical snake has the same basic magnetic structure but is more complicated. To achieve no beam shift and no beam deflection in one magnetic device, helical pitches and rotating angles were carefully calculated. Compared to a superconducting magnet, a normal warm magnet must have a large cross- sectional area of conductors which make it difficult to design a magnet with large helical pitch. We developed a modified window frame structure to accommodate the large number of conductors. Its three dimensional magnetic field was simulated by using OPERA3D/TOSCA. 3 Refs.

  8. Extração de rodovias utilizando SNAKES

    OpenAIRE

    Oliveira, Rafael Montanhini Soares de [UNESP

    2003-01-01

    A obtenção de informações a partir da extração de feições em fotos aéreas e imagens de satélite é um dos principais objetivos da nova tecnologia de automação em Fotogrametria Digital. Este trabalho propõe a extração de rodovias, e a conexão de segmentos de rodovias extraidos por outros extratores de feições, utilizando modelos de contorno ativo ou snakes. Snakes foi introduzido há quase duas décadas e consiste em uma curva representada parametricamente e controlada por injunções fotométricas ...

  9. Skeleton extraction based on the topology and Snakes model

    Directory of Open Access Journals (Sweden)

    Yuanxue Cai

    Full Text Available A new skeleton line extraction method based on topology and flux is proposed by analyzing the distribution characteristics of the gradient vector field in the Snakes model. The distribution characteristics of the skeleton line are accurately obtained by calculating the eigenvalues of the critical points and the flux of the gradient vector field. Then the skeleton lines can be effectively extracted. The results also show that there is no need for the pretreatment or binarization of the target image. The skeleton lines of complex gray images such as optical interference patterns can be effectively extracted by using this method. Compared to traditional methods, this method has many advantages, such as high extraction accuracy and fast processing speed. Keywords: Skeleton, Snakes model, Topology, Photoelasticity image

  10. Fossorial snake genus Apostolepis from South America (Serpentes: Colubridae: Elapomorphinae

    Directory of Open Access Journals (Sweden)

    De Lema, Thales

    2001-07-01

    Full Text Available An update commented list of the snake genus Apostolepis from South America, with keys for identification of the species. They are fossorial snakes that present different coloration according their distribution: (a 7 to 3 dark stripes coloration, without light nuchal collar (if present, vestigial, with snout not projected beyond jaws - in Amazonian and enclaves within Caatinga domain; (b 5 dark striped dorsal pattern, snout projected, usually without white nuchal collars — from region of contact between Cerrado and Chaco domains; (c dorsal pattern coloration uniformly red, with nucho-cervical collars, snout usually projected — in Cerrado with dispersion to Chaco and Caatinga; (d 2 or none dark stripes dorsally, venter immaculate or with black blotches, snout projecting: (e an aberrant pattern with oblique black dorsal stripes, without collars, head black and snout projecting — one species in an enclave within Caatinga, with 17 rows of scales instead of 15.

  11. [Comparative research of lumbar disc herniation treated with acupuncture and snake moxibustion].

    Science.gov (United States)

    Ma, Sheng; Ma, Jun; Pan, Jing-Nian; Zhang, Xiao-Su

    2010-07-01

    To compare the effects on lumbar disc snake herniation between acupuncture in combination of snake moxibustion with simple acupuncture or snake moxibustion. One hundred and twenty cases of lumbar disc herniation patients were randomly divided into an acupuncture and snake moxibustion group (group A, 60 cases), a acupuncture control group (group B, 30 cases) and a snake moxibustion control group (group C, 30 cases). In group A, acupuncture was applied to Shenshu (BL 23), Dachangshu (BL 25) and tender points bilateral to the spine, once a day. Additionally, at the end of acupuncture on the 1st day of a week, snake moxibustion was applied for one time. In group B and group C, acupuncture or snake moxibustion was applied respectively. The excellent rate was 95.0% (57/60) in group A, which was superior to that of 70.0% (21/30) in group B and 66.7% (20/30) in group C (both P efficiency on lumbar disc hernation treated with acupuncture and snake moxibustion is superior to that with either acupuncture or snake moxibustion.

  12. Diversity of toxic components from the venom of the evolutionarily distinct black whip snake, Demansia vestigiata.

    Science.gov (United States)

    St Pierre, Liam; Birrell, Geoff W; Earl, Stephen T; Wallis, Tristan P; Gorman, Jeffrey J; de Jersey, John; Masci, Paul P; Lavin, Martin F

    2007-08-01

    Included among the more than 300 species of elapid snakes worldwide is the Australian genus Demansia, or whip snakes. Despite evidence to suggest adverse clinical outcomes from envenomation by these snakes, together with confusion on their true phylogenetic relationship to other Australian elapids, not a single toxin sequence has previously been reported from the venom of a Demansia species. We describe here a combined proteomic and transcriptomic approach characterizing the venom from the black whip snake, Demansia vestigiata. A total of 13 distinct toxin families were identified, including homologues of all of the major toxic components previously reported from the venom of other Australian elapids, such as factor X-like prothrombin activators, neurotoxins, phospholipases, cysteine rich secretory proteins, textilinin-like molecules, nerve growth factors, l-amino acid oxidases, vespryns, 5' nucleotidases, metalloproteinases, and C-type lectins as well as a novel dipeptidyl peptidase family. Phylogenetic analysis of these sequences revealed an early evolutionary split of the black whip snake from all other characterized Australian snakes, with a low degree of sequence identity between D. vestigiata and the other snakes, across all toxin families. The results of this study have important implications not only for the further characterization of venom from whip snakes, but also for our understanding of the evolutionary relationship of Australian snake species.

  13. Chemosensory responses to chemical and visual stimuli in five species of colubrid snakes

    Directory of Open Access Journals (Sweden)

    Anthony J. Saviola

    2012-07-01

    Full Text Available Snakes utilize chemical and visual stimuli during predation, however the emphasis on these cues and which cues are used to initiate predation varies among species. For example, rattlesnakes using the ambush strategy rely on chemical cues to locate an ambush station, then visual and thermal cues to initiate envenomating strikes, then chemical cues again to track prey. By contrast, many natricine snakes use chemical cues to initiate predation, increasing the rate of tongue flicking regardless of whether visual cues are present. The present study examined the individual and interactive effects of chemical and visual stimuli of prey on the predatory behavior of five snake taxa representing three feeding guilds. Bull snakes (Pituophis catenifer, Eastern Corn snakes (Pantherophis guttatus, and Midland Rat snakes (Scotophis spiloides have a diet primarily consisting of mammals; Western Fox snakes (Mintonius vulpina prey primarily on bird eggs; and Common Kingsnakes (Lampropeltis getula prey equally on mammals and reptiles. Three patterns of response to chemical and visual stimuli of the test prey (Mus musculus were observed. Mammal specialists responded to chemical cues. Fox snakes responded to visual cues, but not to chemical cues. Kingsnakes exhibited increased rates of tongue flicking in response to both chemical and visual stimuli. This study suggests correlations between the evolution of prey preference, foraging ecology and the utilization of chemical or visual stimuli by snakes.

  14. The phylogenetic relationships of Pachyrhachis problematicus, and the evolution of limblessness in snakes (Lepidosauria, Squamata)

    Science.gov (United States)

    Zaher, Hussam; Rieppel, Olivier

    1999-12-01

    We have revisited the type material of Pachyrhachis problematicus, a fossil snake from the Cenomanian (Cretaceous) of the Middle East, and found a number of characters in need of revision with respect to its recent re-description. A new interpretation is given for several cranial characters. There is no identifiable regionalization of the presacral-vertebral column beyond that found in booid snakes. The identification of a free sacral rib in Pachyrhachis is more parsimoniously interpreted as the first lymphapophysis. It is questionable that the pelvic rudiment would have been suspended from the axial skeleton. We have also extensively reviewed the evidence that is believed to link Pachyrhachis, and with it all other snakes, to a mosasauroid ancestor. We were not able to corroborate this hypothesis, which involves characters related to the dentition, braincase morphology, and the intramandibular joint. Instead, re-analysis of the phylogenetic relationships of Pachyrhachis corroborates the hypothesis that it represents the sister-group of macrostomatan snakes, i.e., advanced snakes. Given that Pachyrhachis is nested within the hierarchy of snakes, it is entirely possible that this snake re-developed almost complete hind limbs. A less parsimonious hypothesis would be to consider the hind limbs to have been lost independently in the major basal clades of extant snakes (Scolecophidia, Anilioidea, and Macrostomata). The latter hypothesis is considered a serious possibility given the recently described findings on the mechanisms of limb development in Python, which could account for the highly variable pattern of hindlimb reduction found among basal snakes.

  15. Estimating prey size and number in crayfish-eating snakes, genus Regina

    Science.gov (United States)

    Godley, J.S.; McDiarmid, R.W.; Rojas, N.N.

    1984-01-01

    Snakes of the genus Regina feed almost exclusively on crayfish. The paired, symmetrical gastroliths of crayfish are not digested and are detectable from x-rays of the snake. Gastrolith length is directly proportional to carapace length and can be obtained from x-rays. Carapace length can be converted to kcal of ingested energy. Using these relationships and repeated captures of radio-telemetered Regina, estimates of food consumption and energy intake by freeliving snakes are feasible. New information on prey selectivity, feeding behavior, and predator-prey size relations in Regina grahami and R. septemvittata are presented and compared with similar data for other snakes.

  16. Reproductive trade-offs in the elapid snakes Austrelaps superbus and Austrelaps ramsayi

    National Research Council Canada - National Science Library

    Rohr, Detlef H

    2001-01-01

    Reproductive traits and the trade-offs among these traits were examined in two venomous terrestrial elapid snakes, the Australian lowland copperhead, Austrelaps superbus, and the Australian highland...

  17. Tick infestation on wild snakes in northern part of western Ghats of India.

    Science.gov (United States)

    Pandit, Pranav; Bandivdekar, Ruta; Geevarghese, G; Pande, Satish; Mandke, Omkar

    2011-05-01

    In total, 167 individuals of 30 species of snakes belonging to 22 genera and five families were examined for tick infestation from November 2008 to March 2010. Only two species of snakes, Ptyas mucosa (L., 1758) (Indian rat snake) and Naja naja (L., 1758) (spectacled cobra), were found infested by ticks. All ticks collected were identified to be Amblyomma gervaisi [previously Aponomma gervaisi (Lucas, 1847) 1. The average prevalence of these ticks on Indian rat snakes (n=48) was 29.16%, with abundance of 7.02 ticks per individual; on spectacled cobras (n=20), average prevalence was 30.00%, with abundance of 6.9 ticks per individual. The nymphs and males were predominant. All the ticks were found on the dorsal aspect of the body of the snake, and no ticks were recorded on the head, tail, or ventral body. The rate of tick infestation was highest in scrubland and was lowest in evergreen forests. Female Indian rat snakes showed higher tick infestation rates than male Indian rat snakes. Using Mann-Whitney U test, we found that longer snakes of both species had significantly higher rate of tick infestation in both the species of snakes.

  18. Transient snakes in an ohmic plasma associated with a minor disruption in the HT-7 Tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Songtao; Xu, Liqing; Hu, Liqun; Chen, Kaiyun [Chinese Academy of Sciences, Hefei (China)

    2014-05-15

    A transient burst (∼2 ms, an order of the fast-particle slowdown timescale) of a spontaneous snake is observed for the first time in a HT-7 heavy impurity ohmic plasma. The features of the low-Z impurity snake are presented. The flatten electron profile due to the heavy impurity reveals the formation of a large magnetic island. The foot of the impurity accumulation is consistent with the location of the transient snake. The strong frequency-chirping behaviors and the spatial structures of the snake are also presented.

  19. Identification and comparative analysis of the epidermal differentiation complex in snakes

    Science.gov (United States)

    Brigit Holthaus, Karin; Mlitz, Veronika; Strasser, Bettina; Tschachler, Erwin; Alibardi, Lorenzo; Eckhart, Leopold

    2017-01-01

    The epidermis of snakes efficiently protects against dehydration and mechanical stress. However, only few proteins of the epidermal barrier to the environment have so far been identified in snakes. Here, we determined the organization of the Epidermal Differentiation Complex (EDC), a cluster of genes encoding protein constituents of cornified epidermal structures, in snakes and compared it to the EDCs of other squamates and non-squamate reptiles. The EDC of snakes displays shared synteny with that of the green anole lizard, including the presence of a cluster of corneous beta-protein (CBP)/beta-keratin genes. We found that a unique CBP comprising 4 putative beta-sheets and multiple cysteine-rich EDC proteins are conserved in all snakes and other squamates investigated. Comparative genomics of squamates suggests that the evolution of snakes was associated with a gene duplication generating two isoforms of the S100 fused-type protein, scaffoldin, the origin of distinct snake-specific EDC genes, and the loss of other genes that were present in the EDC of the last common ancestor of snakes and lizards. Taken together, our results provide new insights into the evolution of the skin in squamates and a basis for the characterization of the molecular composition of the epidermis in snakes. PMID:28345630

  20. A longitudinal study of Salmonella from snakes used in a public outreach program.

    Science.gov (United States)

    Goupil, Brad A; Trent, Ava M; Bender, Jeff; Olsen, Karen E; Morningstar, Brenda R; Wünschmann, Arno

    2012-12-01

    Snakes are considered to be a source of Salmonella infection for humans, but little is known about the actual serotype prevalence in healthy snakes over time. Twelve snakes involved in a public outreach program, representing seven different species, were tested weekly for shedding of Salmonella sp. over a period of 10 consecutive weeks. The snakes were housed in close proximity but in separate exhibits. Fresh fecal samples (when available) or cloacal swabs were cultured for Salmonella sp., and subsequent Salmonella isolates were serotyped. As representatives of the feed source, the feces of two mice and the intestines of one rat were cultured weekly. Fecal samples from 11 of the 12 snakes were positive for Salmonella at least once. Seven (58%) of 12 snakes were culture positive five times or more. The weekly prevalence of Salmonella shedding varied between 25% and 66%. Two or more different serotypes were isolated from nine snakes over time; however, a predominant serotype was generally isolated from each of these snakes. Altogether 15 different serotypes were identified. Serotypes of public health concern included Newport, Oranienburg, and Muenchen. Two samples from feeder rodents were positive for Salmonella. The results are consistent with previous studies showing high intestinal colonization rates with Salmonella sp. in snakes. Frequent and intermittent shedding of multiple serotypes was evident. Feeder rodents might serve as a source for intestinal colonization. Appropriate handling protocols should be implemented for all reptiles associated with public outreach programs to minimize risk of Salmonella transmission to the public.

  1. Skeletal heterochrony is associated with the anatomical specializations of snakes among squamate reptiles.

    Science.gov (United States)

    Werneburg, Ingmar; Sánchez-Villagra, Marcelo R

    2015-01-01

    Snakes possess a derived anatomy, characterized by limb reduction and reorganization of the skull and internal organs. To understand the origin of snakes from an ontogenetic point of view, we conducted comprehensive investigations on the timing of skeletal elements, based on published and new data, and reconstructed the evolution of the ossification sequence among squamates. We included for the first time Varanus, a critical taxon in phylogenetic context. There is comprehensive delay in the onset of ossification of most skeletal elements in snakes when compared to reference developmental events through evolution. We hypothesize that progressing deceleration accompanied limb reduction and reorganization of the snake skull. Molecular and morphological studies have suggested close relationship of snakes to either amphisbaenians, scincids, geckos, iguanids, or varanids. Likewise, alternative hypotheses on habitat for stem snakes have been postulated. Our comprehensive heterochrony analyses detected developmental shifts in ossification for each hypothesis of snake origin. Moreover, we show that reconstruction of ancestral developmental sequences is a valuable tool to understand ontogenetic mechanisms associated with major evolutionary changes and test homology hypotheses. The "supratemporal" of snakes could be homolog to squamosal of other squamates, which starts ossification early to become relatively large in snakes. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

  2. Snake fungal disease in North America: U.S. Geological Survey updates

    Science.gov (United States)

    Thompson, Noelle E.; Lankau, Emily W.; Moede Rogall, Gail

    2018-01-12

    Snake fungal disease (SFD) results from a skin infection that has been documented only in snakes. Historically, reports of snakes with skin infections of unknown origin have been sporadic. Recently, the number of reported cases of skin infections in snakes has increased substantially. This emerging infectious disease, confirmed in numerous species of snakes, is caused by the fungus Ophidiomyces ophiodiicola. As of August 2017, O. ophiodiicola has been detected in at least 23 States and one Canadian Province. However, researchers suspect that SFD may be more widely distributed than these documented cases suggest, because efforts to monitor the health of many snake populations are limited. Snake fungal disease may also be underreported in populations where it affects snakes infrequently or in species that develop less severe illness. Signs of SFD include crusted or ulcerated scales, nodules (that is, abnormal bumps) under the skin, and facial disfiguration that can be quite severe, leading to emaciation and death. Many snake populations are already in decline due to habitat loss and dwindling prey populations, and the recent emergence of SFD may accelerate this decline, causing certain species to disappear entirely from some locations.

  3. Spin Transparency Mode in the NICA Collider with Solenoid Siberian Snakes for Proton and Deuteron Beam

    Science.gov (United States)

    Kovalenko, A. D.; Butenko, A. V.; Mikhaylov, V. A.; Kondratenko, M. A.; Kondratenko, A. M.; Filatov, Yu N.

    2017-12-01

    Two solenoid Siberian Snakes are required to obtain ion polarization in spin transparency mode of the NICA collider. The snake solenoids with a total field integral of 2×50 T·m are placed into the straight sections of the NICA collider. It allows one to control polarization of protons and deuterons up to 13.5 GeV/c and 4 GeV/c respectively. The snakes introduce a strong betatron oscillation coupling. The calculations of orbital parameters of proton and deuteron beams in the NICA collider with solenoid Snakes are presented.

  4. Ballistic and snake photon imaging for locating optical endomicroscopy fibres

    Science.gov (United States)

    Tanner, M. G.; Choudhary, T. R.; Craven, T. H.; Mills, B.; Bradley, M.; Henderson, R. K.; Dhaliwal, K.; Thomson, R. R.

    2017-01-01

    We demonstrate determination of the location of the distal-end of a fibre-optic device deep in tissue through the imaging of ballistic and snake photons using a time resolved single-photon detector array. The fibre was imaged with centimetre resolution, within clinically relevant settings and models. This technique can overcome the limitations imposed by tissue scattering in optically determining the in vivo location of fibre-optic medical instruments. PMID:28966848

  5. NEW ASPECTS FOR TREATMENT OF SNAKE BITE: A REVIEW

    OpenAIRE

    Abraham Jobin; Rai Neeta

    2012-01-01

    Recommendation of the effective dose to the medical facility and all the possible condition. Much of the first aid currently carried out is ineffective and dangerous The right method will get the victim to the hospital quickly, without recourse to traditional medical approaches which can dangerously delay effective treatment and will supply the doctor with the best possible information on arrival .Different consideration of the inapplicable method like PIM different treatment of the snake bit...

  6. Pentastomids of wild snakes in the Australian tropics ☆

    OpenAIRE

    Kelehear, Crystal; Spratt, David M.; O’Meally, Denis; Shine, Richard

    2013-01-01

    Pentastomids are endoparasites of the respiratory system of vertebrates, maturing primarily in carnivorous reptiles. Adult and larval pentastomids can cause severe pathology resulting in the death of their intermediate and definitive hosts. The study of pentastomids is a neglected field, impaired by risk of zoonoses, difficulties in species identification, and life cycle complexities. We surveyed wild snakes in the tropics of Australia to clarify which host species possess these parasites, an...

  7. SNAKE BITE WITH TOXIC DEMYELINATION – A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Justin

    2016-02-01

    Full Text Available INTRODUCTION Snakebite is an important cause of mortality and morbidity in India. India has the highest number of deaths due to snake bite1 Neurotoxicity due to snakebite is well-known with varied presentation.2 Common cases of snakebites are of saw-scaled viper (Echis carinatus, Russell’s viper (a viperidae, krait (Bungarus caeruleus, common cobra (Naja naja king cobra (Ophiophagus hannah.3

  8. SNAKE BITE WITH TOXIC DEMYELINATION – A CASE REPORT

    OpenAIRE

    Justin; Manivannan,; Ramu

    2016-01-01

    INTRODUCTION Snakebite is an important cause of mortality and morbidity in India. India has the highest number of deaths due to snake bite1 Neurotoxicity due to snakebite is well-known with varied presentation.2 Common cases of snakebites are of saw-scaled viper (Echis carinatus), Russell’s viper (a viperidae), krait (Bungarus caeruleus), common cobra (Naja naja) king cobra (Ophiophagus hannah).3

  9. Medical humanities in Nepal--snakes and ladders.

    Science.gov (United States)

    Shankar, P Ravi; Piryani, R M; Morgan, Huw; Thapa, T P

    2010-03-01

    In the last decade there has been a quantitative growth in medical schools in Nepal, a developing country in South Asia. Medical Humanities (MH) uses disciplines traditionally termed as the humanities in the pursuit of medical educational goals. The subject is slowly developing in Nepal. Sessions have been conducted at Manipal College of Medical Sciences, Pokhara and KIST Medical College, Lalitpur. In this article the authors examine inhibitory factors (snakes) and facilitating factors (ladders) for the development of the subject in Nepal.

  10. Minor snake venom proteins: Structure, function and potential applications.

    Science.gov (United States)

    Boldrini-França, Johara; Cologna, Camila Takeno; Pucca, Manuela Berto; Bordon, Karla de Castro Figueiredo; Amorim, Fernanda Gobbi; Anjolette, Fernando Antonio Pino; Cordeiro, Francielle Almeida; Wiezel, Gisele Adriano; Cerni, Felipe Augusto; Pinheiro-Junior, Ernesto Lopes; Shibao, Priscila Yumi Tanaka; Ferreira, Isabela Gobbo; de Oliveira, Isadora Sousa; Cardoso, Iara Aimê; Arantes, Eliane Candiani

    2017-04-01

    Snake venoms present a great diversity of pharmacologically active compounds that may be applied as research and biotechnological tools, as well as in drug development and diagnostic tests for certain diseases. The most abundant toxins have been extensively studied in the last decades and some of them have already been used for different purposes. Nevertheless, most of the minor snake venom protein classes remain poorly explored, even presenting potential application in diverse areas. The main difficulty in studying these proteins lies on the impossibility of obtaining sufficient amounts of them for a comprehensive investigation. The advent of more sensitive techniques in the last few years allowed the discovery of new venom components and the in-depth study of some already known minor proteins. This review summarizes information regarding some structural and functional aspects of low abundant snake venom proteins classes, such as growth factors, hyaluronidases, cysteine-rich secretory proteins, nucleases and nucleotidases, cobra venom factors, vespryns, protease inhibitors, antimicrobial peptides, among others. Some potential applications of these molecules are discussed herein in order to encourage researchers to explore the full venom repertoire and to discover new molecules or applications for the already known venom components. Copyright © 2016. Published by Elsevier B.V.

  11. Water Cycle Dynamics in the Snake River Basin, Alaska

    Science.gov (United States)

    Busey, R.; Hinzman, L. D.

    2009-12-01

    Alaska’s Seward Peninsula is underlain in the south by areas of near-freezing, continuous and discontinuous permafrost. These conditions make it susceptible to changing climatic conditions such as acceleration of the hydrologic cycle or general atmospheric warming. This study looks at the hydrologic record of the Snake River over the mid-twentieth century through present. The Snake River basin drains an area of about 22 square kilometers into Norton Sound near the Bering Strait, off the western coast of Alaska. Climate for this area is maritime in summer and somewhat continental in winter once the sea ice forms. Hydrometeorological parameters have been measured locally for more than fifty years with temperature being measured regularly over the last 100 years. Discharge has been measured in the Snake River intermittently over that time period as well. This study looks closely at drivers of inter-annual variations in soil moisture in the basin over the observational record using a physically based numerical hydrological model. Unlike many areas of Alaska, the meteorological record at Nome, located at the mouth of the watershed, shows no statistically significant increase in precipitation over either the last 30 years or the last 100 years. However, there has been a small increase in temperature over the 100 year time period.

  12. [Understanding snake venoms: 50 years of research in Latin America].

    Science.gov (United States)

    Gutiérrez, José María

    2002-06-01

    As a tribute to Revista de Biología Tropical in its 50th anniversary, this review describes some of the main research efforts carried out in the study of the chemical composition and the mechanism of action of toxins present in the venoms of snakes distributed in Latin America. Venom proteins involved in neurotoxicity, coagulopathies, hemorrhage and muscle necrosis are discussed, together with a description of the inflammatory reactions elicited by these venoms and toxins. In addition, the search for inhibitory substances present in plants and animals that may be utilized in the neutralization of venoms is analyzed. Some of the clinical studies performed on snakebite envenomations in Latin America are also reviewed, together with the development of technologies aimed at improving the quality of antivenoms produced in the region. Toxinology has become a fruitful and stimulating research field in Latin America which has contributed to a better understanding of snake venoms as well as to an improved management of snake bitten patients.

  13. CORAL SNAKE ANTIVENOM PRODUCED IN CHICKENS (Gallus domesticus

    Directory of Open Access Journals (Sweden)

    Irma Aguilar

    2014-01-01

    Full Text Available The production of anti-snake venom from large mammal's blood has been found to be low-yielding and arduous, consequently, antivenom immunoglobulins for treatment are achieved regularly as polyvalent serum. We have standardized an undemanding technique for making purified immunoglobulin IgY antivenom consisting of polyclonal antibodies against coral snake venom in the egg yolk of immunized hens. We have adapted a reported process of antibody purification from egg yolks, and achieved 90% antibody purity. The customized technique consisted of the removal of lipids from distilled water-diluted egg yolks by a freeze–thaw sequence. The specific immunoglobulins were present in the egg yolk for up to 180 days postimmunization. Therefore, by means of small venom quantities, a significant amount of immunoglobulins were found in an adequately purified state (The obtained material contained about 90% pure IgY. The antigen binding of the immunoglobulins was detected by a double immunodiffusion test. Titers of antibodies in the yolk were estimated with a serum protection assay (Median effective dose = ED50 (ED50= 477 mg/kg. Given that breeding hens is economically feasible, egg gathering is noninvasive and the purification of IgY antibodies is quick and easy, chicken immunization is an excellent alternative for the production of polyclonal antibodies. To the best of our knowledge, this is the first coral snake antivenom prepared in birds.

  14. Micrurus snake venoms activate human complement system and generate anaphylatoxins.

    Science.gov (United States)

    Tanaka, Gabriela D; Pidde-Queiroz, Giselle; de Fátima D Furtado, Maria; van den Berg, Carmen; Tambourgi, Denise V

    2012-01-16

    The genus Micrurus, coral snakes (Serpentes, Elapidae), comprises more than 120 species and subspecies distributed from the south United States to the south of South America. Micrurus snake bites can cause death by muscle paralysis and further respiratory arrest within a few hours after envenomation. Clinical observations show mainly neurotoxic symptoms, although other biological activities have also been experimentally observed, including cardiotoxicity, hemolysis, edema and myotoxicity. In the present study we have investigated the action of venoms from seven species of snakes from the genus Micrurus on the complement system in in vitro studies. Several of the Micrurus species could consume the classical and/or the lectin pathways, but not the alternative pathway, and C3a, C4a and C5a were generated in sera treated with the venoms as result of this complement activation. Micrurus venoms were also able to directly cleave the α chain of the component C3, but not of the C4, which was inhibited by 1,10 Phenanthroline, suggesting the presence of a C3α chain specific metalloprotease in Micrurus spp venoms. Furthermore, complement activation was in part associated with the cleavage of C1-Inhibitor by protease(s) present in the venoms, which disrupts complement activation control. Micrurus venoms can activate the complement system, generating a significant amount of anaphylatoxins, which may assist due to their vasodilatory effects, to enhance the spreading of other venom components during the envenomation process.

  15. Spatial and temporal drivers of phenotypic diversity in polymorphic snakes.

    Science.gov (United States)

    Cox, Christian L; Davis Rabosky, Alison R

    2013-08-01

    Color polymorphism in natural populations presents an ideal opportunity to study the evolutionary drivers of phenotypic diversity. Systems with striking spatial, temporal, and qualitative variation in color can be leveraged to study the mechanisms promoting the distribution of different types of variation in nature. We used the highly polymorphic ground snake (Sonora semiannulata), a putative coral snake mimic with both cryptic and conspicuous morphs, to compare patterns of neutral genetic variation and variation over space and time in color polymorphism to investigate the mechanistic drivers of phenotypic variation across scales. We found that strong selection promotes color polymorphism across spatial and temporal scales, with morph frequencies differing markedly between juvenile and adult age classes within a single population, oscillating over time within multiple populations, and varying drastically over the landscape despite minimal population genetic structure. However, we found no evidence that conspicuousness of morphs was related to which color pattern was favored by selection or to any geographic factors, including sympatry with coral snakes. We suggest that complex patterns of phenotypic variation in polymorphic systems may be a fundamental outcome of the conspicuousness of morphs and that explicit tests of temporal and geographic variation are critical to the interpretation of conspicuousness and mimicry.

  16. Coral snake antivenom produced in chickens (Gallus domesticus).

    Science.gov (United States)

    Aguilar, Irma; Sánchez, Elda E; Girón, María E; Estrella, Amalid; Guerrero, Belsy; Rodriguez-Acosta, F Alexis

    2014-01-01

    The production of anti-snake venom from large mammal's blood has been found to be low-yielding and arduous, consequently, antivenom immunoglobulins for treatment are achieved regularly as polyvalent serum. We have standardized an undemanding technique for making purified immunoglobulin IgY antivenom consisting of polyclonal antibodies against coral snake venom in the egg yolk of immunized hens. We have adapted a reported process of antibody purification from egg yolks, and achieved 90% antibody purity. The customized technique consisted of the removal of lipids from distilled water-diluted egg yolks by a freeze-thaw sequence. The specific immunoglobulins were present in the egg yolk for up to 180 days postimmunization. Therefore, by means of small venom quantities, a significant amount of immunoglobulins were found in an adequately purified state (The obtained material contained about 90% pure IgY). The antigen binding of the immunoglobulins was detected by a double immunodiffusion test. Titers of antibodies in the yolk were estimated with a serum protection assay (Median effective dose = ED50) (ED50= 477 mg/kg). Given that breeding hens is economically feasible, egg gathering is noninvasive and the purification of IgY antibodies is quick and easy, chicken immunization is an excellent alternative for the production of polyclonal antibodies. To the best of our knowledge, this is the first coral snake antivenom prepared in birds.

  17. Scales microstructure of snakes from the Egyptian area.

    Science.gov (United States)

    Allam, Ahmed A; Abo-Eleneen, Rasha E

    2012-11-01

    The morphology of many organisms seems to be related to the environments in which they live. Many snakes are so similar in their morphological patterns that it becomes quite difficult to distinguish any adaptive divergence that may have occurred. Many authors have suggested that the microstructure of the reptile's scales has important functional value. Herein, we investigate variations on the micromorphology of the external surface of dorsal scales on the head, the mid-body region (trunk), and the tail of Rhomphotyphlops braminus (Typhlopidae), Eryx jaculus (Boidae), Psammophis sibilans (Colubridae), Naja haje (Elapidae) and Echis carinatus (Viperidae). The specimens were metallized and analyzed by scanning electron microscopy. All species displayed unique dorsal scale surface microstructures of the investigated regions. The microstructural pattern of the scales of head, trunk, and tail differs in different species of these snakes. In conclusion, we detected ecomorphologic relationships between extant dorsal scale microstructures and snake microhabitat, enabling us to hypothesize that environmental pressures have significant influences not only on these animals' macrostructure, but also on its microstructure as well.

  18. Efficiency of snake sampling methods in the Brazilian semiarid region.

    Science.gov (United States)

    Mesquita, Paula C M D; Passos, Daniel C; Cechin, Sonia Z

    2013-09-01

    The choice of sampling methods is a crucial step in every field survey in herpetology. In countries where time and financial support are limited, the choice of the methods is critical. The methods used to sample snakes often lack objective criteria, and the traditional methods have apparently been more important when making the choice. Consequently researches using not-standardized methods are frequently found in the literature. We have compared four commonly used methods for sampling snake assemblages in a semiarid area in Brazil. We compared the efficacy of each method based on the cost-benefit regarding the number of individuals and species captured, time, and financial investment. We found that pitfall traps were the less effective method in all aspects that were evaluated and it was not complementary to the other methods in terms of abundance of species and assemblage structure. We conclude that methods can only be considered complementary if they are standardized to the objectives of the study. The use of pitfall traps in short-term surveys of the snake fauna in areas with shrubby vegetation and stony soil is not recommended.

  19. Micrurus snake venoms activate human complement system and generate anaphylatoxins

    Directory of Open Access Journals (Sweden)

    Tanaka Gabriela D

    2012-01-01

    Full Text Available Abstract Background The genus Micrurus, coral snakes (Serpentes, Elapidae, comprises more than 120 species and subspecies distributed from the south United States to the south of South America. Micrurus snake bites can cause death by muscle paralysis and further respiratory arrest within a few hours after envenomation. Clinical observations show mainly neurotoxic symptoms, although other biological activities have also been experimentally observed, including cardiotoxicity, hemolysis, edema and myotoxicity. Results In the present study we have investigated the action of venoms from seven species of snakes from the genus Micrurus on the complement system in in vitro studies. Several of the Micrurus species could consume the classical and/or the lectin pathways, but not the alternative pathway, and C3a, C4a and C5a were generated in sera treated with the venoms as result of this complement activation. Micrurus venoms were also able to directly cleave the α chain of the component C3, but not of the C4, which was inhibited by 1,10 Phenanthroline, suggesting the presence of a C3α chain specific metalloprotease in Micrurus spp venoms. Furthermore, complement activation was in part associated with the cleavage of C1-Inhibitor by protease(s present in the venoms, which disrupts complement activation control. Conclusion Micrurus venoms can activate the complement system, generating a significant amount of anaphylatoxins, which may assist due to their vasodilatory effects, to enhance the spreading of other venom components during the envenomation process.

  20. Riparian vegetation of the Snake River in Washington State

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, R.C. [Pacific Northwest Lab., Richland, WA (United States); Mettler, L. [US Army Corps of Engineers (United States)

    1994-06-01

    In January 1992, the US Army Corps of Engineers selected reservoir drawdown and lowered pool elevation as the preferred alternative in the Columbia River Salmon Flow Measured Options Analysis/Environmental Impact Statement (EIS). During March 1992, reservoirs upstream from Lower Granite and Little Goose Dams on the Snake River were drawn down below the minimum operating pool (MOP), which is 5 vertical feet below ordinary high water level (0@) level. The reservoir upstream from Lower Granite Dam was drawn down to approximately 37 ft below 0 while that upstream of Little Goose Dam was drawn down to approximately 15 ft (4.5 m) below MOP. Following the drawdown (March 1--31, 1992), the reservoirs of all four dams in the Snake River of Washington State (Lower Granite, Little Goose, Lower Monumental, Ice Harbor) were maintained at MOP (April 1--July 31,1992). This allowed a defined portion of shoreline to be exposed for an extended period. The objectives of the study were to monitor impacts to the associated upland, riparian/wetland, and aquatic vegetation and newly exposed shorelines of four reservoirs of the Snake River during the flow measures study; and monitor the newly exposed shorelines for invasion of pioneering species during the entire period of the wildlife monitoring study.

  1. A new snake of the genus Hydrops from Colombia A new snake of the genus Hydrops from Colombia

    Directory of Open Access Journals (Sweden)

    Dunn Emmett Reid

    1944-09-01

    Full Text Available While in Popayán recently Mr. F. C. Lehmann showed me the snakes in his care in the collection of the University of Cauca. Among them was a Hydrops which was taken in swampy terrain in the vicinity of the city (1760 m. As Hydrops was supposed to be confined to the area east of the Andes this was quite a surprise. The species seems to be undescribed and may be called: Hydrops lehmanni sp. nov. While in Popayán recently Mr. F. C. Lehmann showed me the snakes in his care in the collection of the University of Cauca. Among them was a Hydrops which was taken in swampy terrain in the vicinity of the city (1760 m. As Hydrops was supposed to be confined to the area east of the Andes this was quite a surprise. The species seems to be undescribed and may be called: Hydrops lehmanni sp. nov.

  2. Report on the Status of the Eastern Indigo Snake (Drymarchon couperi) on St. Vincent National Wildlife Refuge, Franklin County, Florida

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report discusses the status of the Indigo Snake and efforts being taken to repopulate habitat. The Eastern Indigo Snake (Drymarchon couperi) was listed as a...

  3. Lower Snake River Juvenile Salmon Migration Feasibility Report/Environmental Impact Statement. Appendix D: Natural River Drawdown Engineering

    National Research Council Canada - National Science Library

    2002-01-01

    ... (collectively called the Lower Snake River Project) and their effects on four lower Snake River salmon and steelhead stocks listed for protection under the Endangered Species Act (ESA). The U.S...

  4. The interaction of the antitoxin DM43 with a snake venom metalloproteinase analyzed by mass spectrometry and surface plasmon resonance

    DEFF Research Database (Denmark)

    Brand, Guilherme D; Salbo, Rune; Jørgensen, Thomas J D

    2012-01-01

    DM43 is a circulating dimeric antitoxin isolated from Didelphis aurita, a South American marsupial naturally immune to snake envenomation. This endogenous inhibitor binds non-covalently to jararhagin, the main hemorrhagic metalloproteinase from Bothrops jararaca snake venom, and efficiently...

  5. Snake-like chromatin in conjunctival cells of a population aged 30-60 years from Copenhagen City

    DEFF Research Database (Denmark)

    Bjerrum, Kirsten Birgitte

    1998-01-01

    ophthalmology, keratoconjunctivitis sicca, Sjögrens Syndrome, epidemiology, imprint biopsy, snake-like chromatin......ophthalmology, keratoconjunctivitis sicca, Sjögrens Syndrome, epidemiology, imprint biopsy, snake-like chromatin...

  6. Molecular basis for prey relocation in viperid snakes.

    Science.gov (United States)

    Saviola, Anthony J; Chiszar, David; Busch, Chardelle; Mackessy, Stephen P

    2013-03-01

    Vertebrate predators use a broad arsenal of behaviors and weaponry for overcoming fractious and potentially dangerous prey. A unique array of predatory strategies occur among snakes, ranging from mechanical modes of constriction and jaw-holding in non-venomous snakes, to a chemical means, venom, for quickly dispatching prey. However, even among venomous snakes, different prey handling strategies are utilized, varying from the strike-and-hold behaviors exhibited by highly toxic elapid snakes to the rapid strike-and-release envenomation seen in viperid snakes. For vipers, this mode of envenomation represents a minimal risk predatory strategy by permitting little contact with or retaliation from prey, but it adds the additional task of relocating envenomated prey which has wandered from the attack site. This task is further confounded by trails of other unstruck conspecific or heterospecific prey. Despite decades of behavioral study, researchers still do not know the molecular mechanism which allows for prey relocation. During behavioral discrimination trials (vomeronasal responsiveness) to euthanized mice injected with size-fractionated venom, Crotalus atrox responded significantly to only one protein peak. Assays for enzymes common in rattlesnake venoms, such as exonuclease, L-amino acid oxidase, metalloproteinase, thrombin-like and kallikrein-like serine proteases and phospholipase A(2), showed that vomeronasal responsiveness was not dependent on enzymatic activity. Using mass spectrometry and N-terminal sequencing, we identified the proteins responsible for envenomated prey discrimination as the non-enzymatic disintegrins crotatroxin 1 and 2. Our results demonstrate a novel and critical biological role for venom disintegrins far beyond their well-established role in disruption of cell-cell and cell-extracellular matrix interactions. These findings reveal the evolutionary significance of free disintegrins in venoms as the molecular mechanism in vipers allowing for

  7. High helmintic infection of the European grass snake, Natrix natrix and the dice snake, Natrix tessellate (Serpentes: Colubridae from Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Yossefi

    2014-02-01

    Full Text Available Objective: To determine the helminth parasites of Natrix natrix Linnaeus, 1758 (N. natrix and Natrix tessellata Laurenti, 1768 (N. tessellate in north of Iran. Methods: Eighteen snakes including nine N. natrix and nine N. tessellata from Mazandaran Province, north of Iran were collected and examined during March 2011 to October 2011 for helminth parasites. The collected specimens were fixed and preserved in 70% ethanol. Results: All of the examined snakes (100% were infected with parasitic helminth. The list of extracted helminths both in N. natrix and N. tessellata includes one Nematode: Rhabdias fuscovenosa (larva, one Digenea: Telorchis assula and one Cestoda: Ophiotaenia europaea. The infection rate of Ophiotaenia europaea, Telorchis assula and Rhabdias fuscovenosa (larva from collected snakes were 100%, 83.3% and 61.1%, respectively. Moreover, in the current investigation the morphological characteristics of the collected helminths were described elaborately. Conclusions: This is the first survey on helminth parasites from N. tessellata in Iran and the helminthes are reported for the first time from this host in Iran.

  8. Introduction to the symposium "New frontiers from marine snakes to marine ecosystems".

    Science.gov (United States)

    Lillywhite, Harvey B; Brischoux, François

    2012-08-01

    Interest in sea snakes and mythological "sea serpents" dates to ancient times and is represented in the writings of Aristotle, early voyagers, and explorers, and references in the Bible. Since then, awareness of the myriad species of snakes inhabiting the oceans has grown at a gradual pace. Scientific investigations into the biology of marine snakes-especially those in behavior, physiology, and other disciplines requiring living animals or tissues-have been comparatively challenging owing to difficulties in acquiring, transporting, handling, and husbanding these secondarily marine vertebrates. A broadening perspective with increasing interest in these animals peaked during the 1960s and 1970s, and literature from this period contributed to a growing knowledge that marine snakes comprise a very diverse fauna and are a significant part of marine ecosystems. Two persons figured prominently as influential drivers of research on sea snakes during this period, namely William Dunson and Harold Heatwole, and this symposium recognizes the contributions of these two individuals. Following a decline in scientific publications on sea snakes during the 1980s and 1990s, there has been a renaissance of scientific interest in recent years, and a wealth of new research findings has improved the understanding of phylogeny and diversity of marine snakes while simultaneously recognizing threats to marine ecosystems arising from climate change and other anthropogenic causes. The purposes of the symposium are to (1) illustrate the importance and relevance of sea snakes as contributors to better understanding a range of issues in marine biology, (2) establish and promote the use of marine systems as models for investigating conceptual issues related to environment, changing climate, and persistence of biological communities, with focus on marine snakes as novel or useful examples, (3) promote interest in sea snakes as useful organisms for study by scientists in a range of disciplines who

  9. Dehydration and drinking behavior of the marine file snake Acrochordus granulatus.

    Science.gov (United States)

    Lillywhite, Harvey B; Heatwole, Harold; Sheehy, Coleman M

    2014-01-01

    Dehydration and drinking behaviors were investigated in the little file snake (Acrochordus granulatus) collected from marine populations in the Philippines and in Australia. File snakes dehydrate in seawater and do not drink seawater when dehydrated in air and offered seawater to drink. Dehydrated file snakes drink freshwater, and the threshold of dehydration for first drinking response is a deficit of -7.4% ± 2.73% (mean ± SD) of original body mass. The thirst mechanism in this species is more sensitive than that recently studied in sea snakes. The volume of water ingested increases with increasing dehydration. Mean plasma osmolality was 278.89 ± 33.17 mMol/kg, mean hematocrit was 59% ± 5.45%, and both decreased in snakes that drank freshwater following acclimation in seawater. Snakes always drank freshwater at the water's surface, testing water with tongue flicks between each swallowing of water. Some snakes ingested large volumes of freshwater, approaching 50% of body mass. Visual observations and measurements of osmolality in plasma and stomach fluids suggest that water is taken up from the gut and dilutes body fluids slowly over the course of 48 h or longer. Eighty percent of snakes that were collected during the dry season (following >4 mo of drought) in Australia drank freshwater immediately following their capture, indicating that snakes were dehydrated in their marine environment even when known to have been feeding at the time. Snakes kept in seawater maintained a higher state of body condition when freshwater was periodically available. These results support a growing conclusion that diverse taxa of marine snakes require environmental sources of freshwater to maintain water balance, contrary to earlier belief. Identifying the freshwater requirements of secondarily marine vertebrates is important for better understanding how they maintain water balance in marine habitats, especially with respect to conservation in changing environments.

  10. Chemosensory age discrimination in the snake Boa constrictor (Serpentes: Boidae

    Directory of Open Access Journals (Sweden)

    Marianne Gabirot

    2012-12-01

    Full Text Available Many snakes are able to use their chemosensory system to detect scent of conspecifics, which is important in many social contexts. Age discrimination based on chemical cues may be especially important to ensure access to sexually mature potential partners. In this study, we used 24 individual Boa constrictor snakes (12 adults mature and 12 non-mature individuals that had been captured in different areas of Ecuador, and were maintained in captivity at the Vivarium of Quito. We used tongue-flick experiments to examine whether these snakes were able to discriminate between scents from mature and non-mature individuals. Results showed that B. constrictor snakes used chemical cues to recognize conspecifics and that the scent of individuals of different ages elicited chemosensory responses of different magnitudes. The scents from adult conspecifics elicited the quickest and highest chemosensory responses (i.e., short latency times and high tongue-flick rates, although we did not find differential responses to scent of males and females. The magnitude of the responses was lower to scent of sub adult individuals, and then even lower to scent of juvenile snakes, but in all cases the scent of snakes was discriminated from a blank control. We discuss the potential chemical mechanisms that may allow age recognition and its implications for social and sexual behavior of this snake species.Muchas serpientes son capaces de usar su sistema quimiosensorial para detectar el olor de individuos coespecíficos, lo que es importante en muchos contextos sociales. La discriminación de la edad basada en señales químicas puede ser especialmente importante para asegurar el acceso a parejas potenciales que sean sexualmente maduras. En este estudio, usamos 24 individuos de una especie de boa (Boa constrictor (12 individuos adultos y 12 inmaduros que habían sido capturados en diferentes partes de Ecuador y eran mantenidos en cautividad el Vivarium de Quito. Usamos

  11. 33 CFR 165.804 - Snake Island, Texas City, Texas; mooring and fleeting of vessels-safety zone.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Snake Island, Texas City, Texas... Guard District § 165.804 Snake Island, Texas City, Texas; mooring and fleeting of vessels—safety zone. (a) The following is a safety zone: (1) The west and northwest shores of Snake Island; (2) The...

  12. 75 FR 62137 - Notice of Intent To Collect Fees on Public Land in Fremont County, Idaho, Upper Snake Field...

    Science.gov (United States)

    2010-10-07

    ... Snake Field Office Under the Federal Lands Enhancement Act AGENCY: Bureau of Land Management, Interior...), the Upper Snake Field Office will begin collecting fees for the day use area and a fee for use of the... collection at this site. Six months after the publication of this notice, the Upper Snake Field Office will...

  13. Mutual mortality of great horned owl and southern black racer: a potential risk of raptors preying on snakes

    Science.gov (United States)

    Roger W. Perry; Raymond E. Brown; D. Craig Rudolph

    2001-01-01

    We encountered a dead southern black racer snake (Coluber constrictor priapus) coiled around a dead Great Horned Owl (Bubo virginianus). We suggest the owl was strangled by the snake before the snake did of wounds inflicted by the owl. There are previous reports of intense physical struggle between Great Horned Owls (and...

  14. Medicinal plants used to treat Snake bite by Fulani Herdsmen in ...

    African Journals Online (AJOL)

    Dr. Ameen

    ethnopharmacology revealed several of these medicinal plants with potential to treat snake bite. This work was designed to document medicinal plants used by Fulani herdsmen in Taraba State, Nigeria, for the treatment of snake bites. Information provided will enable further study on the efficacy of the medicinal plants so ...

  15. Snake venoms: A brief treatise on etymology, origins of terminology, and definitions.

    Science.gov (United States)

    Weinstein, Scott A

    2015-09-01

    The ancient perceptions of "venomous" and "poisonous snakes", as well as the Indo-European (IE) etymological origins of the term "venom" specifically associated with snakes are considered. Although several ancient cultures perceived snakes as symbols of fecundity and renewal, concurrent beliefs also associated venomous snakes with undesirable human characteristics or as portending non-propitious events. The respective IE roots of the terms "venom" and "poison", "wen" and "poi" refer to desire or the act of ingesting liquids. The origin of the term, "venom", is associated with polytheistic cults that emphasized attainment of desires sometimes assisted by "love potions", a term later interpolated with the word, "poison". Specific interpretation of the term, venom, has varied since its first probable use in the mid-Thirteenth Century. The definition of snake venom has long been contended, and interpretations have often reflected emphasis on the pharmacological or experimental toxicity of medically relevant snake venoms with less regard for the basic biological bases of these venoms, as well as those from snakes with no known medical significance. Several definitions of "snake venom" and their defining criteria are reviewed, and critical consideration is given to traditional criteria that might facilitate the future establishment of a biologically accurate definition. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  16. 75 FR 6020 - Electrical Interconnection of the Lower Snake River Wind Energy Project

    Science.gov (United States)

    2010-02-05

    ... Bonneville Power Administration Electrical Interconnection of the Lower Snake River Wind Energy Project... Puget Sound Energy Inc., a Large Generator Interconnection Agreement for interconnection of up to 1250... their proposed Lower Snake River Wind Energy Project (Wind Project) in Garfield and Columbia counties...

  17. Spawning Distribution of Fall Chinook Salmon in the Snake River : Annual Report 1999.

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Aaron P.

    2000-04-01

    This report is separated into 2 chapters. The chapters are (1) Progress toward determining the spawning distribution of supplemented fall chinook salmon in the Snake River in 1999; and (2) Fall chinook salmon spawning ground surveys in the Snake River, 1999.

  18. [A fish prey found in the coral snake Micrurus alleni (Serpentes: Elapidae) in Costa Rica].

    Science.gov (United States)

    Solórzano, Alejandro

    2005-01-01

    A fish prey found in the coral snake Micrurus alleni (Serpentes: Elapidae) in Costa Rica. The presence of a small specimen of the swamp eel Synbranchus marmoratus (84 mm total length) in the stomach contents of an adult coral snake Micrurus alleni with 692 mm total length from the Caribbean versant of Costa Rica is reported. This eel was swallowed headfirst.

  19. Garter snake population dynamics from a 16-year study: considerations for ecological monitoring

    Science.gov (United States)

    Amy J. Lind; Hartwell H. Welsh Jr; David A. Tallmon

    2005-01-01

    Snakes have recently been proposed as model organisms for addressing both evolutionary and ecological questions. Because of their middle position in many food webs they may be useful indicators of trophic complexity and dynamics. However, reliable data on snake populations are rare due to the challenges of sampling these patchily distributed, cryptic, and often...

  20. Analytical solutions for spin response functions in model storage rings with Siberian Snakes

    Energy Technology Data Exchange (ETDEWEB)

    Mane, S.R. [Convergent Computing Inc., P.O. Box 561, Shoreham, NY 11786 (United States)], E-mail: srmane@optonline.net

    2009-03-01

    I present analytical solutions for the spin response functions for radial field rf dipole spin flippers in models of storage rings with one Siberian Snake or two diametrically opposed orthogonal Siberian Snakes. The solutions can serve as benchmarks tests for computer programs. The spin response functions can be used to calculate the resonance strengths for radial field rf dipole spin flippers in storage rings.

  1. Population structure, body mass, activity, and orientation of an aquatic snake (Seminatrix pygaea) during a drought

    Science.gov (United States)

    Dodd, C.K.

    1993-01-01

    The snout – vent length, tail length, weight, sex, activity, and orientation of a population of swamp snakes (Seminatrix pygaea) in north – central Florida were recorded from 1985 through 1990. A small temporary pond was monitored for 1343 days, using a drift fence – pitfall trap sampling regime. I captured 123 different snakes, plus 45 recaptures. Juveniles comprised 89% of the snakes at the pond. Females were generally longer and weighed more than males, although regression analysis showed no differences between the sexes in the relationship of length versus wet body mass. Males had longer tails than females. The sex ratio of snakes with a snout – vent length of more than 150 mm was 1:1. Activity occurred throughout the year but peaked during summer. Hydroperiod and weather conditions did not appear to influence snake activity. During the latter years of the study, a regional drought that began in the mid-1980s became quite severe. However, drought had little direct effect on overland migration or body condition but caused snakes to leave or to shorten the amount of time they spent within the pond basin. Snakes immigrated and emigrated nonrandomly; orientation was directed to and from the nearest large water body. Certain temporary ponds may comprise developmental habitat for Seminatrix pygaea. The dynamic wet – dry climatic cycles in southeastern North America may lead to the formation of metapopulations in some aquatic snakes.

  2. A study on endoparasitic and ectoparasitic fauna of snakes in Mizoram, India

    OpenAIRE

    Gautam Patra; Sonjoy Kumar Borthakur; Seikh Sahanawaz Alam; Subhamoy Ghosh; Hmar Lalliankimi; Hniang Lalrinkima

    2017-01-01

    Objective: To record the prevalence of parasitic fauna of snakes from different parts of Mizoram, India. Methods: Collected fecal samples of different snakes were examined by sedimentation and floatation techniques. Similarly, blood samples were examined for presence of any haemoprotozoa following Giemsa staining technique. Ectoparasites were identified on the basis of morphological keys. Scanning electron microscopy (SEM) was performed for detailed surface structure studies...

  3. Asymmetry of mandibular dentition is associated with dietary specialization in snail-eating snakes

    National Research Council Canada - National Science Library

    Masaki Hoso

    2017-01-01

    .... A remarkable exception is known in the snail-eating snakes of the family Pareidae: almost all the pareid snakes have much more teeth on the right mandible than on the left for functional specialization in feeding on the dextral majority of land snails...

  4. Snake bite on scrotum – a case report | Arshad | Pan African Medical ...

    African Journals Online (AJOL)

    A 22-year old man was bitten by a snake on his scrotum. This interesting and unusual case occurred in the rural area of District Aligarh, India. The niqueness of the case lies in the fact that scrotum is an extremely rare and unusual site for snake bite. Further, with negligible local signs of envenoming the patient presented ...

  5. Comparison of cranial form and function in association with diet in natricine snakes.

    Science.gov (United States)

    Hampton, Paul M

    2011-12-01

    The skull of squamates has many functions, with food acquisition and ingestion being paramount. Snakes vary interspecifically in the frequency, size, and types of prey that are consumed. Natural selection should favor phenotypes that minimize the costs of energy acquisition; therefore, trophic morphology should reflect a snake's primary prey type to enhance some aspect of feeding performance. I measured 19 cranial variables for six natricine species that vary in the frequency with which they consume frogs and fish. Both conventional and phylogenetically corrected analyses indicated that fish-eating snakes have relatively longer upper and lower jaw elements than frog-eating snakes, which tended to have broader skull components. I also compared the ratio of the in-lever to the out-lever lengths of the jaw-closing mechanism [jaw mechanical advantage (MA)] among species. Fish-eating snakes had significantly lower MAs in the jaws than did the frog-eating snakes. This result suggests that piscivores have faster closing jaws and that the jaws of frog-eating snakes have higher closing forces. Cranial morphology and the functional demands of prey capture and ingestion appear to be associated with primary prey type in natricine snakes. Copyright © 2011 Wiley-Liss, Inc.

  6. Anti-snake Venom Activities of Ethanol and Aqueous Extract of ...

    African Journals Online (AJOL)

    Snake bite leads to medical emergencies and sometimes death. It is clinically managed by administration of monovalent/polyvalent antisera and it exhibit early or late adverse reactions and sometimes these adverse effects lead to fatalities. Cassia hirsute has been used against snake bite by the traditional healers; however ...

  7. Clinical Presentation And Outcome Of Snake-Bite Patients At Zamko ...

    African Journals Online (AJOL)

    Objective: To assess the pattern of clinical presentation and management outcome of snake bite victims treated in a comprehensive health centre in a rural setting in North-Central zone of Nigeria where snake bite morbidity and mortality are known to be unacceptably high. Methods: All records of admission in the ...

  8. Fatal cutaneous mycosis in tentacled snakes caused by the chrysosporium anamorph of nannizziposis vriesii

    DEFF Research Database (Denmark)

    Bertelsen, Mads Frost; Crawshaw, Graham J.; Sigler, Lynne

    2005-01-01

    The fungus Chrysosporium anamorph of Nannizziopsis vriesii was identified as the caurse of fatal, multifocal, heterophilic dermatitis in for freshwater aquatic captive-bred tentacled snakes......The fungus Chrysosporium anamorph of Nannizziopsis vriesii was identified as the caurse of fatal, multifocal, heterophilic dermatitis in for freshwater aquatic captive-bred tentacled snakes...

  9. Pre-Service Biology Teachers' and Primary School Students' Attitudes toward and Knowledge about Snakes

    Science.gov (United States)

    Tomazic, Iztok

    2011-01-01

    Snakes are controversial animals emblazoned by legends, but also endangered as a result of human prejudice and fear. The author investigated gender and age-related differences in attitudes to and knowledge of snakes comparing samples of school children and pre-service teachers. It was found that although pre-service teachers had better knowledge…

  10. An audit of the clinical profile of snake bites among female patients ...

    African Journals Online (AJOL)

    Background: A lot of work had been done on the clinical profiles of patients with snake bites but none on female patients alone. In this medical audit, we undertook to study the clinical profiles of snake bites among female patients seen over a two year period at a federal Government designated treatment centre, Zamko.

  11. Constructing snake-in-the-box codes and families of such codes covering the hypercube

    NARCIS (Netherlands)

    Haryanto, L.

    2007-01-01

    A snake-in-the-box code (or snake) is a list of binary words of length n such that each word differs from its successor in the list in precisely one bit position. Moreover, any two words in the list differ in at least two positions, unless they are neighbours in the list. The list is considered to

  12. Snake bites in Nigeria: A study of the prevalence and treatment in ...

    African Journals Online (AJOL)

    Purpose: Although snake bites occur frequently in Benin City, the prevalence has not been documented. This study was therefore done to determine the prevalence, morbidity, mortality, and the orthodox treatment of victims. Methods: The study was retrospective and data on victims of snake bite covering a period of twenty ...

  13. Snakes of the Savannah River Plant with Information About Snakebite Prevention and Treatment.

    Science.gov (United States)

    Gibbons, Whit

    This booklet is intended to provide information on the snakes of South Carolina, to point out the necessary steps to avoid a snakebite, and to indicate the current medical treatment for poisonous snakebite. It includes a checklist of South Carolina reptiles and a taxonomic key for the identification of snakes in the Savannah River Plant. Three…

  14. Science Education Researchers as Orthographers: Documenting Keiyo (Kenya) Knowledge, Learning and Narratives about Snakes.

    Science.gov (United States)

    Thomson, Norman

    2003-01-01

    Advances the argument that science educators have a pivotal role as orthographers in preserving and promoting science for all. Interviews Keiyo elders and students (n=748) to determine indigenous names for snakes and how Keiyo oral narratives of snakes are used in teaching and learning. Uses the data to document Keiyo language and construct…

  15. The Grass Snake and the Basilisk: From Pre-Christian Protective House God to the Antichrist

    NARCIS (Netherlands)

    Lenders, H.J.R.; Janssen, I.A.W.

    2014-01-01

    The grass snake owes its far northern distribution in Europe to the production and hoarding of dung from stock breeding. Dung heaps appear to be perfect breeding sites that surpass ‘natural’ reproduction sites in quality. Here we point out that the grass snake's dependency on manure goes back to

  16. Secondary analysis of snake bite data in the Western Region of Ghana

    African Journals Online (AJOL)

    2016-06-02

    Jun 2, 2016 ... Method: The study was a descriptive cross-sectional review of 2006 - 2010 snake bite secondary data generated by the Western Regional Health Information Office in Ghana. Data was .... Estimate of the burden of Snake bites in Sub-Saharan Africa; A meta-analytic approach. Toxicon. 2011; 57(4): 586-99.

  17. 75 FR 49514 - Notice of Availability for the Little Snake Proposed Resource Management Plan and Final...

    Science.gov (United States)

    2010-08-13

    ... Bureau of Land Management Notice of Availability for the Little Snake Proposed Resource Management Plan... Proposed Resource Management Plan (RMP)/Final Environmental Impact Statement (EIS) for the Little Snake... Visual Resource Management Class II, and designated as a right-of-way exclusion area unless associated...

  18. Progressive Loss of Function in a Limb Enhancer during Snake Evolution

    Energy Technology Data Exchange (ETDEWEB)

    Kvon, Evgeny Z.; Kamneva, Olga K.; Melo, Uirá S.; Barozzi, Iros; Osterwalder, Marco; Mannion, Brandon J.; Tissières, Virginie; Pickle, Catherine S.; Plajzer-Frick, Ingrid; Lee, Elizabeth A.; Kato, Momoe; Garvin, Tyler H.; Akiyama, Jennifer A.; Afzal, Veena; Lopez-Rios, Javier; Rubin, Edward M.; Dickel, Diane E.; Pennacchio, Len A.; Visel, Axel

    2016-10-20

    The evolution of body shape is thought to be tightly coupled to changes in regulatory sequences, but specific molecular events associated with major morphological transitions in vertebrates have remained elusive. In this paper, we identified snake-specific sequence changes within an otherwise highly conserved long-range limb enhancer of Sonic hedgehog (Shh). Transgenic mouse reporter assays revealed that the in vivo activity pattern of the enhancer is conserved across a wide range of vertebrates, including fish, but not in snakes. Genomic substitution of the mouse enhancer with its human or fish ortholog results in normal limb development. In contrast, replacement with snake orthologs caused severe limb reduction. Synthetic restoration of a single transcription factor binding site lost in the snake lineage reinstated full in vivo function to the snake enhancer. Our results demonstrate changes in a regulatory sequence associated with a major body plan transition and highlight the role of enhancers in morphological evolution.

  19. Morphology of the snake spectacle reflects its evolutionary adaptation and development

    DEFF Research Database (Denmark)

    Da Silva, Mari-Ann Otkjaer; Heegaard, Steffen; Wang, Tobias

    2017-01-01

    Background Covering the eye of all snakes is a transparent integumental structure known as the spectacle. In order to determine variations in spectacle thickness among species, the spectacles of 217 alcohol-preserved museum specimens of 44 species belonging to 14 different families underwent...... found in the Usambara bush viper (Viperidae) with a thickness of 74 ± 9 μm and the absolute thickest spectacle was found in the red-tailed pipe snake (Cylindrophiidae) which had a spectacle thickness of 244 ± 57 μm. Fossorial and aquatic snakes had significantly thicker spectacles than arboreal...... and terrestrial snakes. When spectacle thickness was correlated to eye size (horizontal spectacle diameter), Gray’s earth snake (Uropeltidae) had the lowest ratio (1:7) and the cottonmouth (Viperidae) had the highest ratio (1:65). Multivariable and phylogenetic analyses showed that spectacular thickness could...

  20. Putting the brakes on snake venom evolution: the unique molecular evolutionary patterns of Aipysurus eydouxii (Marbled sea snake) phospholipase A2 toxins.

    Science.gov (United States)

    Li, Min; Fry, Bryan G; Kini, R Manjunatha

    2005-04-01

    Accelerated evolution of toxins is a unique feature of venoms, with the toxins evolving via the birth-and-death mode of molecular evolution. The venoms of sea snakes, however, are remarkably simple in comparison to those of land snakes, which contain highly complex venoms. Aipysurus eydouxii (Marbled sea snake) is a particularly unique sea snake, feeding exclusively upon fish eggs. Secondary to this ecological change, the fangs have been lost and the venom glands greatly atrophied. We recently showed that the only neurotoxin (a three-finger toxin) gene found in the sea snake A. eydouxii has a dinucleotide deletion, resulting in the loss of neurotoxic activity. During these studies, we isolated and identified a number of cDNA clones encoding isozymes of phospholipase A(2) (PLA(2)) toxins from its venom gland. Sixteen unique PLA(2) clones were sequenced from the cDNA library and TA cloning of reverse transcription-polymerase chain reaction products. Phylogenetic analysis of these clones revealed that less diversification of the PLA(2) toxins has occurred in the A. eydouxii venom gland in comparison to equivalent terrestrial and other marine snakes. As there is no longer a positive selection pressure acting upon the venom, mutations have accumulated in the toxin-coding regions that would have otherwise had a deleterious effect upon the ability to use the venom for prey capture. Such mutations include substitutions of highly conserved residues; in one clone, the active site His(48) is replaced by Arg, and in two other clones, highly conserved cysteine residues are replaced. These mutations significantly affect the functional and structural properties of these PLA(2) enzymes, respectively. Thus, in A. eydouxii, the loss of the main neurotoxin is accompanied by a much slower rate of molecular evolution of the PLA(2) toxins as a consequence of the snake's shift in ecological niche. This is the first case of decelerated evolution of toxins in snake venom.

  1. Cheyletus eruditus (taurrus): an effective candidate for the biological control of the snake mite (Ophionyssus natricis).

    Science.gov (United States)

    Schilliger, Lionel H; Morel, Damien; Bonwitt, Jesse H; Marquis, Olivier

    2013-09-01

    The most commonly encountered ectoparasite in captive snakes is the hematophagous snake mite (Ophionyssus natricis). Infected snakes often exhibit lethargy, dysecdysis, pruritus, crusting dermatitis (sometimes progressing to abscesses), and behavioral changes (increased bathing time, rubbing against objects). Anemia and septicemia are occasional complications. Eliminating snake mites from a collection is frustrating. Insecticidal and acaricidal compounds used in mammals can be used against O. natricis infestation in reptiles, but they all are potentially neurotoxic to reptiles. The use of a biological agent to control the snake mite was first developed by using the predatory mites Hypoaspis miles and Hypoaspis aculeifer. However, no data are available regarding the potential of these mites to control O. natricis. Furthermore, the survival and predatory behavior of H. aculeifer and H. miles decreases above 28 degrees C, which is the lower value of the optimal temperature zone range required for rearing snakes. The aim of this study is to identify the ability of the predatory mite Cheyletus eruditus to control O. natricis. In the first experiment, 125 O. natricis mites where placed in separate plastic tubes together with the same number of C. eruditus mites. After 48 hr, the survival rate of snake mites was 6% compared with 92% in the control group (n = 125, P snake) ball pythons, with an average of 13 O. natricis per individual, were placed in separate cages with 1,000 C. eruditus mites + vermiculite After 15 days, only an average of two mites per snake remained, compared with 48 per snake in the control group (t-test, P < 0,01).

  2. Scales drive detection, attention, and memory of snakes in wild vervet monkeys (Chlorocebus pygerythrus).

    Science.gov (United States)

    Isbell, Lynne A; Etting, Stephanie F

    2017-01-01

    Predatory snakes are argued to have been largely responsible for the origin of primates via selection favoring expansion of the primate visual system, and even today snakes can be deadly to primates. Neurobiological research is now beginning to reveal the mechanisms underlying the ability of primates (including humans) to detect snakes more rapidly than other stimuli. However, the visual cues allowing rapid detection of snakes, and the cognitive and ecological conditions contributing to faster detection, are unclear. Since snakes are often partially obscured by vegetation, the more salient cues are predicted to occur in small units. Here we tested for the salience of snake scales as the smallest of potential visual cues by presenting four groups of wild vervet monkeys (Chlorocebus pytherythrus) with a gopher snake (Pituophis catenifer) skin occluded except for no more than 2.7 cm, in natural form and flat, the latter to control for even small curvilinear cues from their unusual body shape. Each of these treatments was preceded by a treatment without the snakeskin, the first to provide a baseline, and the second, to test for vigilance and memory recall after exposure to the snakeskin. We found that (1) vervets needed only a small portion of snakeskin for detection, (2) snake scales alone were sufficient for detection, (3) latency to detect the snakeskin was longer with more extensive and complex ground cover, and (4) vervets that were exposed to the snakeskin remembered where they last saw "snakes", as indicated by increased wariness near the occluding landmarks in the absence of the snakeskin and more rapid detection of the next presented snakeskin. Unexpectedly, adult males did not detect the snakeskin as well as adult females and juveniles. These findings extend our knowledge of the complex ecological and evolutionary relationships between snakes and primates.

  3. Inter- and intraspecific variation in mercury bioaccumulation by snakes inhabiting a contaminated river floodplain.

    Science.gov (United States)

    Drewett, David V V; Willson, John D; Cristol, Daniel A; Chin, Stephanie Y; Hopkins, William A

    2013-04-01

    Although mercury (Hg) is a well-studied contaminant, knowledge about Hg accumulation in snakes is limited. The authors evaluated Hg bioaccumulation within and among four snake species (northern watersnakes, Nerodia sipedon; queen snakes, Regina septemvittata; common garter snakes, Thamnophis sirtalis; and rat snakes, Elaphe obsoleta [Pantherophis alleghaniensis]) from a contaminated site on the South River (Waynesboro, VA, USA) and two nearby reference sites. Total Hg (THg) concentrations in northern watersnake tail tissue at the contaminated site ranged from 2.25 to 13.84 mg/kg dry weight (mean: 4.85 ± 0.29), or 11 to 19 times higher than reference sites. Blood THg concentrations (0.03-7.04 mg/kg wet wt; mean: 2.24 ± 0.42) were strongly correlated with tail concentrations and were the highest yet reported in a snake species. Within watersnakes, nitrogen stable isotope values indicated ontogenetic trophic shifts that correlated with THg bioaccumulation, suggesting that diet plays a substantial role in Hg exposure. Female watersnakes had higher mean THg concentrations (5.67 ± 0.46 mg/kg) than males (4.93 ± 0.49 mg/kg), but no significant differences between sexes were observed after correcting for body size. Interspecific comparisons identified differences in THg concentrations among snake species, with more aquatic species (watersnakes and queen snakes) accumulating higher mean concentrations (5.60 ± 0.40 and 4.59 ± 0.38 mg/kg in tail tissue, respectively) than the more terrestrial species, garter snakes and rat snakes (1.28 ± 0.32 and 0.26 ± 0.09 mg/kg, respectively). The results of the present study warrant further investigation of potential adverse effects and will aid in prioritizing conservation efforts. Copyright © 2013 SETAC.

  4. Snake cathelicidin from Bungarus fasciatus is a potent peptide antibiotics.

    Directory of Open Access Journals (Sweden)

    Yipeng Wang

    Full Text Available BACKGROUND: Cathelicidins are a family of antimicrobial peptides acting as multifunctional effector molecules of innate immunity, which are firstly found in mammalians. Recently, several cathelicidins have also been found from chickens and fishes. No cathelicidins from other non-mammalian vertebrates have been reported. PRINCIPAL FINDINGS: In this work, a cathelicidin-like antimicrobial peptide named cathelicidin-BF has been purified from the snake venoms of Bungarus fasciatus and its cDNA sequence was cloned from the cDNA library, which confirm the presence of cathelicidin in reptiles. As other cathelicidins, the precursor of cathelicidin-BF has cathelin-like domain at the N terminus and carry the mature cathelicidin-BF at the C terminus, but it has an atypical acidic fragment insertion between the cathelin-like domain and the C-terminus. The acidic fragment is similar to acidic domains of amphibian antimicrobial precursors. Phylogenetic analysis revealed that the snake cathelicidin had the nearest evolution relationship with platypus cathelicidin. The secondary structure of cathelicidin-BF investigated by CD and NMR spectroscopy in the presence of the helicogenic solvent TFE is an amphipathic alpha-helical conformation as many other cathelicidins. The antimicrobial activities of cathelicidin BF against forty strains of microorganisms were tested. Cathelicidin-BF efficiently killed bacteria and some fungal species including clinically isolated drug-resistance microorganisms. It was especially active against Gram-negative bacteria. Furthermore, it could exert antimicrobial activity against some saprophytic fungus. No hemolytic and cytotoxic activity was observed at the dose of up to 400 microg/ml. Cathelicidin-BF could exist stably in the mice plasma for at least 2.5 hours. CONCLUSION: Discovery of snake cathelicidin with atypical structural and functional characterization offers new insights on the evolution of cathelicidins. Potent, broad

  5. Elucidation of trends within venom components from the snake families Elapidae and Viperidae using gel filtration chromatography.

    Science.gov (United States)

    Graham, Robert Leslie James; Graham, Ciaren; Theakston, David; McMullan, Geoff; Shaw, Chris

    2008-01-01

    Research into snake venom components has intensified over the last number of decades, particularly that work directed towards the discovery of novel agents with potential applications in clinical therapy. In the present study we report, for the first time, defined patterns observed in the G-50 chromatographic elution profiles from 30 snake venoms taken from Elapidae and Viperidae families, as well as previously unreported patterns within subfamilies of these snake species. Development of this chromatographic technique thus offers a rapid method for the general classification of snakes within these families as well as providing insights into hitherto uncharacterised trends within the venoms of snake subfamilies that have opened new avenues for further investigation.

  6. Microstructure-mediated Optical Effects in Southern African Snakes

    Directory of Open Access Journals (Sweden)

    Singh Ishan

    2017-01-01

    Full Text Available The scales of the African Viper Bitis arietans were tested for optical effects. Spectral intensity was recorded at incident angles over the visible spectrum for dark, pale, and ventral scale regions. The lowest spectral intensity recordings were associated with scales which have the greatest level of micro-structuring. Our results indicate that scale appearance in B. arietans is a product of microstructure-mediated optical effects. The optical effect may play a role in improving the ecological performance of the snake in its natural environment.

  7. Microstructure-mediated Optical Effects in Southern African Snakes

    Science.gov (United States)

    Singh, Ishan; Alexander, Graham

    2017-03-01

    The scales of the African Viper Bitis arietans were tested for optical effects. Spectral intensity was recorded at incident angles over the visible spectrum for dark, pale, and ventral scale regions. The lowest spectral intensity recordings were associated with scales which have the greatest level of micro-structuring. Our results indicate that scale appearance in B. arietans is a product of microstructure-mediated optical effects. The optical effect may play a role in improving the ecological performance of the snake in its natural environment.

  8. Chlorinated hydrocarbon concentrations in plasma of the Lake Erie water snake (Nerodia sipedon insularum) and northern water snake (Nerodia sipedon sipedon) from the Great Lakes basin in 1998.

    Science.gov (United States)

    Bishop, C A; Rouse, J D

    2000-11-01

    From the Great Lakes basin, concentrations of 59 congener-specific polychlorinated biphenyls (PCBs) and 14 organochlorine pesticides were measured in blood plasma of northern water snake (Nerodia sipedon sipedon) and Lake Erie water snake (Nerodia sipedon insularum), which is endangered in Canada. In 1998, four male adult Lake Erie water snakes were sampled from Pelee Island, western Lake Erie; four male northern water snakes were sampled at Little Lake, about 20 km north of Parry Sound in central Ontario; and four adult gravid female northern water snakes were sampled from Garden Island, eastern Lake Ontario. The blood plasma was pooled by site for a total of three samples analyzed. The Pelee Island sample from male Lake Erie water snakes contained less than half the lipid concentration (0.349%) than samples from the other sites, but it was the most contaminated with PCBs, even on a wet weight basis. Summed concentration of individual PCBs in the Pelee Island sample was 167 ng/g (wet weight), which was 14-fold higher than the next most contaminated sample, which was from Little Lake. The plasma sample from Little Lake contained 12 ng/g (WW) and was four times more contaminated with PCBs than the sample from female snakes from Garden Island, Lake Ontario. Organochlorine pesticide concentrations in plasma were relatively similar among sites. None of the pesticides was found above trace concentrations (0.1-0.9 ng/g) except pp'-DDE, which occurred at 2-5 ng/g among sites. PCB congener patterns in the Lake Erie water snakes were compared to PCB patterns in plasma of common snapping turtle (Chelydra serpentina serpentina) from Lake Ontario, herring gull eggs (Larus argentatus) from western Lake Erie, and mudpuppy eggs (Necturus maculosus) from the Detroit River. The PCB patterns in water snake and herring gull sample were most similar, followed by the pattern in snapping turtle plasma. The presence of more lower-chlorinated chlorobiphenyls in the mudpuppy eggs relative

  9. Extinction, ecological opportunity, and the origins of global snake diversity.

    Science.gov (United States)

    Pyron, R Alexander; Burbrink, Frank T

    2012-01-01

    Snake diversity varies by at least two orders of magnitude among extant lineages, with numerous groups containing only one or two species, and several young clades exhibiting exceptional richness (>700 taxa). With a phylogeny containing all known families and subfamilies, we find that these patterns cannot be explained by background rates of speciation and extinction. The majority of diversity appears to derive from a radiation within the superfamily Colubroidea, potentially stemming from the colonization of new areas and the evolution of advanced venom-delivery systems. In contrast, negative relationships between clade age, clade size, and diversification rate suggest the potential for possible bias in estimated diversification rates, interpreted by some recent authors as support for ecologically mediated limits on diversity. However, evidence from the fossil record indicates that numerous lineages were far more diverse in the past, and that extinction has had an important impact on extant diversity patterns. Thus, failure to adequately account for extinction appears to prevent both rate- and diversity-limited models from fully characterizing richness dynamics in snakes. We suggest that clade-level extinction may provide a key mechanism for explaining negative or hump-shaped relationships between clade age and diversity, and the prevalence of ancient, species-poor lineages in numerous groups. © 2011 The Author(s). Evolution © 2011 The Society for the Study of Evolution.

  10. Unraveling the processing and activation of snake venom metalloproteinases.

    Science.gov (United States)

    Portes-Junior, José A; Yamanouye, Norma; Carneiro, Sylvia M; Knittel, Paloma S; Sant'Anna, Sávio S; Nogueira, Fabio C S; Junqueira, Magno; Magalhães, Geraldo S; Domont, Gilberto B; Moura-da-Silva, Ana M

    2014-07-03

    Snake venom metalloproteinases (SVMPs) are zinc-dependent enzymes responsible for most symptoms of human envenoming. Like matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinase (ADAM) proteins, SVMPs are synthesized as zymogens, and enzyme activation is regulated by hydrolysis of their prodomain, but the processing of SVMPs is still unclear. In this study, we attempted to identify the presence of prodomain in different compartments of snake venom glands as zymogens or in the free form to elucidate some mechanism involved in SVMP activation. Using antibodies obtained by immunization with a recombinant prodomain, bands of zymogen molecular mass and prodomain peptides were detected mostly in gland extracts all along the venom production cycle and in the venom collected from the lumen at the peak of venom production. Prodomain was detected in secretory cells mostly in the secretory vesicles near the Golgi. We hypothesize that the processing of SVMPs starts within secretory vesicles and continues in the lumen of the venom gland just after enzyme secretion and involves different steps compared to ADAMs and MMPs but can be used as a model for studying the relevance of peptides resulting from prodomain processing and degradation for controlling the activity of metalloproteinases.

  11. Learning structural bioinformatics and evolution with a snake puzzle

    Directory of Open Access Journals (Sweden)

    Gonzalo S. Nido

    2016-12-01

    Full Text Available We propose here a working unit for teaching basic concepts of structural bioinformatics and evolution through the example of a wooden snake puzzle, strikingly similar to toy models widely used in the literature of protein folding. In our experience, developed at a Master’s course at the Universidad Autónoma de Madrid (Spain, the concreteness of this example helps to overcome difficulties caused by the interdisciplinary nature of this field and its high level of abstraction, in particular for students coming from traditional disciplines. The puzzle will allow us discussing a simple algorithm for finding folded solutions, through which we will introduce the concept of the configuration space and the contact matrix representation. This is a central tool for comparing protein structures, for studying simple models of protein energetics, and even for a qualitative discussion of folding kinetics, through the concept of the Contact Order. It also allows a simple representation of misfolded conformations and their free energy. These concepts will motivate evolutionary questions, which we will address by simulating a structurally constrained model of protein evolution, again modelled on the snake puzzle. In this way, we can discuss the analogy between evolutionary concepts and statistical mechanics that facilitates the understanding of both concepts. The proposed examples and literature are accessible, and we provide supplementary material (see ‘Data Availability’ to reproduce the numerical experiments. We also suggest possible directions to expand the unit. We hope that this work will further stimulate the adoption of games in teaching practice.

  12. Identification and characterization of novel reptile cathelicidins from elapid snakes.

    Science.gov (United States)

    Zhao, Hui; Gan, Tong-Xiang; Liu, Xiao-Dong; Jin, Yang; Lee, Wen-Hui; Shen, Ji-Hong; Zhang, Yun

    2008-10-01

    Three cDNA sequences coding for elapid cathelicidins were cloned from constructed venom gland cDNA libraries of Naja atra, Bungarus fasciatus and Ophiophagus hannah. The open reading frames of the cloned elapid cathelicidins were all composed of 576bp and coded for 191 amino acid residue protein precursors. Each of the deduced elapid cathelicidin has a 22 amino acid residue signal peptide, a conserved cathelin domain of 135 amino acid residues and a mature antimicrobial peptide of 34 amino acid residues. Unlike the highly divergent cathelicidins in mammals, the nucleotide and deduced protein sequences of the three cloned elapid cathelicidins were remarkably conserved. All the elapid mature cathelicidins were predicted to be cleaved at Valine157 by elastase. OH-CATH, the deduced mature cathelicidin from king cobra, was chemically synthesized and it showed strong antibacterial activity against various bacteria with minimal inhibitory concentration of 1-20microg/ml in the presence of 1% NaCl. Meanwhile, the synthetic peptide showed no haemolytic activity toward human red blood cells even at a high dose of 200microg/ml. Phylogenetic analysis of cathelicidins from vertebrate suggested that elapid and viperid cathelicidins were grouped together in the tree. Snake cathelicidins were evolutionary closely related to the neutrophilic granule proteins (NGPs) from mouse, rat and rabbit. Snake cathelicidins also showed a close relationship with avian fowlicidins (1-3) and chicken myeloid antimicrobial peptide 27. Elapid cathelicidins might be used as models for the development of novel therapeutic drugs.

  13. CLINICO-EPIDEMIOLOGY AND THERAPEUTIC OUTCOME OF SNAKE BITE IN KONASEEMA REGION OF ANDHRA PRADESH

    Directory of Open Access Journals (Sweden)

    Sai Krishna

    2016-03-01

    Full Text Available INTRODUCTION Snake bite is a common and frequently devastating environmental and occupational problem, especially in rural areas of tropical developing countries. Snake bite incidence is high in Andhra Pradesh. With the onset of monsoon the incidence of snake bite used to increase. METHODS Present study is a retrospective study in which all the data of snake bite cases admitted in the Konaseema Institute of Medical Sciences was collected in last two years; details of the patient was obtained from bed head ticket. RESULTS In two years of data collection, 46 snake bite cases are found as per our record. Out of 46 patients, twenty seven were male and nineteen were female. Maximum twenty two (22 patients were between ages 20 to 40 years. Out of forty six patients, forty four recovered and only two patients died, cause of death was acute pulmonary oedema with cardiac arrhythmia. DISCUSSION Most of the patients were given ASV (anti-snake venom, out of that only four patients developed reaction to ASV. Most of the patients who have received ASV were recovered. Only two deaths were reported which was due to acute pulmonary oedema with cardiac arrhythmia. CONCLUSION Awareness and education about snake is required.

  14. Hematology and serum biochemistry of Indian spectacled cobra (Naja naja) and Indian rat snake (Ptyas mucosa).

    Science.gov (United States)

    Muliya, Sanath Krishna; Bhat, Mudraje Narayana

    2016-08-01

    To study the hematology and serum biochemistry parameters of Indian spectacled cobra (Naja naja) and Indian rat snake (Ptyas mucosa) and to evaluate the differences in the same between captive and wild populations. Animals were categorized into four groups, viz., wild Indian spectacled cobra (n=10), wild Indian rat snakes (n=10), captive Indian spectacled cobra (n=10), and captive Indian rat snake (n=10). The snakes were restrained with restraint tubes, and 2 ml of blood was collected from either heart or ventral coccygeal vein. Hematological examinations were performed manually and serum biochemistry assays were performed on semi-automated clinical chemistry analyzer. The values of total erythrocyte count, packed cell volume, and hemoglobin were slightly low in captive spectacled cobras and captive rat snakes compared to wild ones, whereas total leukocyte count was found to be slightly high in wild spectacled cobras compared to captive ones. All the recorded values of biochemical and electrolyte analytes were found to be well within expected range for snakes except for total protein and chloride levels in both the species which was slightly above the expected range. The hematology and serum biochemistry intervals of the two most common Indian snakes are presented here. The data will be useful in routine health evaluations and aiding in better medical management of the species studied. Since this study is the first to report complete hematologic and blood biochemical ranges for the study species, observations made here can also be used as referral intervals for future use.

  15. Snake-Like Robot with Fusion Gait for High Environmental Adaptability: Design, Modeling, and Experiment

    Directory of Open Access Journals (Sweden)

    Kundong Wang

    2017-11-01

    Full Text Available A snake changes its gait to adapt to different environments. A snake-like robot that is able to perform as many or more gaits than a real-life snake has the potential to successfully adapt to a range of environments, similar to a real-life snake. However, only a few mechanisms in the current snake-like framework can perform common gaits. In this paper, a novel snake-like robot is developed to resolve this problem. A multi-gait is established and used as a reference for the articulation design. A non-snake-like mechanism with linear articulation is combined with the classical swing joint. A prototype is designed and constructed for verification and analysis. Two basic main gaits, namely, serpentine and rectilinear locomotion, are fused, and a novel obstacle-aided locomotion based on rectilinear motion is developed. The experiment demonstrates that the robot can generate all of the expected gaits with high movement efficiency.

  16. Morphology of the snake spectacle reflects its evolutionary adaptation and development.

    Science.gov (United States)

    Da Silva, Mari-Ann Otkjaer; Heegaard, Steffen; Wang, Tobias; Gade, Jacob Thorup; Damsgaard, Christian; Bertelsen, Mads Frost

    2017-08-18

    Covering the eye of all snakes is a transparent integumental structure known as the spectacle. In order to determine variations in spectacle thickness among species, the spectacles of 217 alcohol-preserved museum specimens of 44 species belonging to 14 different families underwent optical coherence tomography (OCT) to measure spectacular thickness. Multivariable analyses were made to determine whether family, activity period (diurnal/nocturnal) and habitat (arboreal/terrestrial/fossorial/aquatic) influenced spectacle thickness. The thinnest spectacles in absolute terms were found in the Usambara bush viper (Viperidae) with a thickness of 74 ± 9 μm and the absolute thickest spectacle was found in the red-tailed pipe snake (Cylindrophiidae) which had a spectacle thickness of 244 ± 57 μm. Fossorial and aquatic snakes had significantly thicker spectacles than arboreal and terrestrial snakes. When spectacle thickness was correlated to eye size (horizontal spectacle diameter), Gray's earth snake (Uropeltidae) had the lowest ratio (1:7) and the cottonmouth (Viperidae) had the highest ratio (1:65). Multivariable and phylogenetic analyses showed that spectacular thickness could be predicted by taxonomic family and habitat, but not activity period. This phylogenetically broad systematic study of the thickness of the snake spectacle showed that spectacular thickness varies greatly across snake species and may reflect evolutionary adaptation and development.

  17. Revisiting the fear of snakes in children: the role of aposematic signalling

    Science.gov (United States)

    Souchet, Jérémie; Aubret, Fabien

    2016-01-01

    Why humans fear snakes is an old, yet unresolved debate. Its innate origin from evolutionary causes is debated against the powerful influence early experience, culture, media and religion may have on people’s aversion to snakes. Here we show that the aversion to snakes in human beings may have been mistaken for an aversion to aposematic signals that are commonly displayed by snakes. A total of 635 children were asked to rate single item images as “nice” or “mean”. Snakes, pets and smiley emoticon items were not rated as “mean” unless they displayed subtle aposematic signals in the form of triangular (rather than round) shapes. Another 722 children were shown images featuring two items and asked which item was “nice” and which item was “mean”. This context dependent comparison triggered even sharper responses to aposematic signals. We hypothesise that early primates evolved an aversion for aposematic signals in the form of potentially harmful triangular shapes such as teeth, claws or spikes, not for snakes per se. Further, we hypothesise that this adaptation was in turn exploited by snakes in their anti-predatory threat display as a triangular head or dorsal zig-zag pattern, and is currently the basis for efficient international road-danger signalling. PMID:27886218

  18. The North-South divide in snake bite envenomation in India.

    Science.gov (United States)

    Chauhan, Vivek; Thakur, Suman

    2016-01-01

    Snake bite envenomations are common in rural areas and the incidence peaks during monsoons in India. Prominent venomous species have been traditionally labeled as the 'big four' that includes Cobra, Krait, Russel's viper and Saw scaled viper. Systematic attempts for identification and classification of prevalent snakes in various states of India are missing till now and there is no concrete data on this aspect. The published literature however shows that some species of snakes are more prevalent in a particular region than the other parts of India e.g. Saw scaled vipers in Rajasthan. We reviewed the published literature from various parts of India and found that there is a North-South divide in the snake bite profile from India. Neurotoxic envenomations are significantly higher in North India compared to South India where Hematotoxic envenomations are prevalent. Russel's viper causes local necrosis, gangrene and compartment syndrome. These manifestations have never been reported in North Indian snake bite profile in the published literature. Early morning neuroparalysis caused by Krait is a common problem in North India leading to high mortality after snake bite. This review presents supporting evidence for the North-South divide and proposes a way forward in formulation and revision of guidelines for snake bite in India.

  19. Students' attitudes toward and knowledge about snakes in the semiarid region of Northeastern Brazil.

    Science.gov (United States)

    Alves, Rômulo R N; Silva, Vanessa N; Trovão, Dilma M B M; Oliveira, José V; Mourão, José S; Dias, Thelma L P; Alves, Ângelo G C; Lucena, Reinaldo F P; Barboza, Raynner R D; Montenegro, Paulo F G P; Vieira, Washington L S; Souto, Wedson M S

    2014-03-27

    Humans in various cultures have feared snakes, provoking an aversion and persecution that hinders conservation efforts for these reptiles. Such fact suggests that conservation strategies for snakes should consider the interactions and perceptions of the local population towards these animals. The aim of this study was to investigate students' perception of snakes and if attitudes and knowledge may differ according to gender and local residence (urban or rural). Data was collected in the second half of 2012 and consisted of questionnaires applied to 108 students in the Basic Education School in the municipality of Sumé, located in the semiarid region of Northeastern Brazil. The male respondents recognized more species than female did. Part of the students affirmed to have a fear of snakes, especially women. Nearly half of respondents (49%) showed negative behaviour towards these animals, reflecting the influence of potential risk and myths associated with snakes, and supported by a limited knowledge about these animals and their ecological and utilitarian role. We find that the rural students recognized significantly more species than the urban students. Our results point to the need for educational interventions in order to increase knowledge about the positive aspects associated with snakes, seeking to minimize the influence of myths and beliefs that contribute to a strong aversion to snakes by the locals. Conservation strategies should therefore engage students but also teachers, who are key individuals in the process.

  20. Spiders do not evoke greater early posterior negativity in the event-related potential as snakes.

    Science.gov (United States)

    He, Hongshen; Kubo, Kenta; Kawai, Nobuyuki

    2014-09-10

    It has been long believed that both snakes and spiders are archetypal fear stimuli for humans. Furthermore, snakes have been assumed as stronger threat cues for nonhuman primates. However, it is still unclear whether spiders hold a special status in human perception. The current study explored to what extent spider pictures draw early visual attention [as assessed with early posterior negativity (EPN)] when compared with insects similar to spiders. To measure the EPN, participants watched a random rapid serial presentation of pictures, which consisted of two conditions: spider condition (spider, wasp, bumblebee, beetle) and snake condition (snake, bird). EPN amplitudes revealed no significant difference between spider, wasp, bumblebee, and beetle pictures, whereas EPN amplitudes were significantly larger for snake pictures relative to bird pictures. In addition, EPN amplitudes were significantly larger for snake pictures relative to spider pictures. These results suggest that the early visual attentional capture of animate objects is stronger for snakes, whereas spiders do not appear to hold special early attentional value.