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1

REPRODUCTIVE BIOLOGY OF AGKISTRODON PISCIVORUS LACE PE` DE (SQUAMATA, SERPENTES, VIPERIDAE, CROTALINAE)  

E-print Network

REPRODUCTIVE BIOLOGY OF AGKISTRODON PISCIVORUS LACE´ PE` DE (SQUAMATA, SERPENTES, VIPERIDAE, Springfield, OH 45501, USA ABSTRACT: Aspects of the reproductive biology of male and female Agkistrodon of the male and female urogenital cycles to the reproductive life history of A. piscivorus. New anatomical

Sever, David M.

2

Postprandial thermogenesis in Bothrops moojeni (Serpentes: Viperidae) Stuginski DR (1), Fernandes W (1), Tattersall GJ (2), Abe AS (3)  

E-print Network

Postprandial thermogenesis in Bothrops moojeni (Serpentes: Viperidae) Stuginski DR (1), Fernandes W postprandial thermogenesis in Bothrops moojeni. Briefly, two groups of snakes were fed meals equivalent to 17 words: Bothrops, thermogenesis, feeding behavior, digestion. OriginalPaPer The Journal of Venomous

Tattersall, Glenn

3

Post-fight levels of plasma lactate and corticosterone in male copperheads, Agkistrodon contortrix (Serpentes, Viperidae): differences between winners and losers  

Microsoft Academic Search

During the mating seasons (late summer and spring), male copperheads (Agkistrodon contortrix; Serpentes, Viperidae) engage in aggressive physical interactions for priority of access to females. These fights generally involve two individuals and are characterized by prominent vertical displays, a high degree of physical contact, and the absence of biting. Ritualized aggression does not occur in females. Although intrasexual aggression in

Gordon W. Schuett; Matthew S. Grober

2000-01-01

4

The genus Atheris (Serpentes: Viperidae) in East Africa: Phylogeny and the role of rifting and climate in shaping the current pattern of species diversity.  

PubMed

Past climatic and tectonic events are believed to have strongly influenced species diversity in the Eastern Afromontane Biodiversity Hotspot. We investigated the phylogenetic relationships and historical biogeography of the East African genus Atheris (Serpentes: Viperidae), and explored temporal and spatial relationships between Atheris species across Africa, and the impact of palaeoclimatic fluctuations and tectonic movements on cladogenesis of the genus. Using mitochondrial sequence data, the phylogeny of East African species of Atheris shows congruent temporal patterns that link diversification to major tectonic and aridification events within East Africa over the last 15million years (my). Our results are consistent with a scenario of a delayed direct west-east colonisation of the Eastern Arc Mountains of Atheris by the formation of the western rift. Based on the phylogenetic patterns, this terrestrial, forest-associated genus has dispersed into East Africa across a divided route, on both west-southeasterly and west-northeasterly directions (a C-shaped route). Cladogenesis in the Eastern Arc Mountains and Southern Highlands of Tanzania corresponds to late Miocene and Plio-Pleistocene climatic shifts. Taxonomically, our data confirmed the monophyly of Atheris as currently defined, and reveal four major East African clades, three of which occur in discrete mountain ranges. Possible cryptic taxa are identified in the Atheris rungweensis and A. ceratophora clades. PMID:24952316

Menegon, M; Loader, S P; Marsden, S J; Branch, W R; Davenport, T R B; Ursenbacher, S

2014-10-01

5

Inhibition of hemorrhagic and edematogenic activities of snake venoms by a broad-spectrum protease inhibitor, murinoglobulin; the effect on venoms from five different genera in Viperidae family.  

PubMed

In order to obtain basic data on the effect of broad-spectrum protease inhibitor against local symptoms of Viperidae snake envenomation, inhibitory capacity of rat murinoglobulin on local hemorrhagic and edematogenic activities of venoms from Crotalus atrox, Bothrops jararaca, Lachesis muta muta, Trimeresurus flavoviridis and Echis carinatus sochureki were examined. Murinoglobulin, pre-incubated with the crude venoms at 37 degrees C for 15 min, inhibited hemorrhagic activity of all five venoms to various extents. The activity of C. atrox was almost completely inhibited at the murinoglobulin/venom ratio (w/w) of 20. The activity of B. jararaca, Lachesis muta muta and T. flavoviridis venoms was considerably inhibited at the ratio of 20 (77.2, 80.0 and 86.2% inhibition, respectively), however some of the activity still remained even at the ratio of 40 (84.2, 79.8 and 86.2% inhibition, respectively). Among the five venoms, E. c. sochureki venom is quite resistant to murinoglobulin treatment and statistically significant inhibition was only found at the ratio of 40 (64.1% inhibition). Fibrinolytic and gelatinase activities were more susceptible to murinoglobulin inhibition. The treatment at the ratios of 10 and 20 almost completely inhibited respectively the fibrinolytic and the gelatinase activities of all the venoms. Murinoglobulin treatment also significantly inhibited the edematogenic activity of L. muta muta, T. flavoviridis and Echis carinatus sochureki. The treatment of murinoglobulin at the ratio of 40 considerably suppressed the swelling up to 60 min after subcutaneous injection of L. muta muta and E. c. sochureki venoms, and up to 30 min after T. flavoviridis venom injection. Murinoglobulin is a potent inhibitor against local effects of multiple snake venoms in Viperidae family. PMID:12906888

Ribeiro Filho, Wilker; Sugiki, Masahiko; Yoshida, Etsuo; Maruyama, Masugi

2003-08-01

6

Is the population of Crotalus durissus (Serpentes, Viperidae) expanding in Brazil?  

PubMed Central

Crotalus durissus are found from Mexico to northern Argentina in a highly disjunct distribution. According to some studies, this species is prone to occupy areas disturbed by human activities and floods comprise a plausible method of dispersal as inferred for some North American rattlesnakes. Based on the literature, it seems plausible that Crotalus durissus expanded their natural distribution in Brazil due to floods, but only in a few municipalities in Rio de Janeiro State. Data entries of Butantan Institute, in São Paulo, Brazil, from 1998 to 2012 show a declining tendency of snakes brought by donors. In addition, research shows no evidence of Crotalus durissus being an expanding species in the Brazilian territory. PMID:24314146

2013-01-01

7

Discovery of a Novel Accessory Structure of the Pitviper Infrared Receptor Organ (Serpentes: Viperidae)  

PubMed Central

The facial pits of rattlesnakes, copperheads, lanceheads, bushmasters and other American and Asian pitvipers (Crotalinae) are highly innervated and densely vascularized infrared (IR) receptor organs. For over a century, studies have focused on a small sample of model species from North America and Asia. Based on an expanded survey of Central and South American crotalines, we report a conspicuous accessory structure composed of well-defined papillae that project from the anterior orbital adnexa. The papillae are continuous with the inner chamber of the IR receptor organ and our histological and ultrastructural data suggest that they possess a well-developed nervous network and extensive vascularization; however, they lack the characteristic IR-sensitive terminal nerve masses found in the IR-receptive pit membrane. The function of the IR receptor organ papillae is unknown. PMID:24595025

Bolívar-G, Wilmar; Antoniazzi, Marta M.; Grant, Taran; Jared, Carlos

2014-01-01

8

Feeding, Reproduction, and Morphology of Bothrops mattogrossensis (Serpentes, Viperidae, Crotalinae) in the Brazilian Pantanal  

Microsoft Academic Search

Bothrops mattogrossensis occurs in open wet habitats in the Pantanal of western Brazil. As part of a series of studies focusing on how ecological characters evolved in the genus Bothrops, we gathered information on diet, reproduction, and morphology for B. mattogrossensis using museum specimens. Bothrops mattogrossensis has a generalized diet (anurans, small mammals, lizards, snakes, and centipedes), a plesiomorphic character

Carolina Monteiro; Chad E. Montgomery; Felipe Spina; Ricardo J. Sawaya; Marcio Martins

2006-01-01

9

The role of the vomeronasal organ of crotalines (Reptilia: Serpentes: Viperidae) in predator detection.  

PubMed

Most reptiles and mammals, with the exceptions of crocodilians, aquatic mammals and some primates, have a functional vomeronasal organ that detects and perceives semi-volatile chemicals in the environment. This organ is used in detection of prey and is also important for recognition of conspecifics and potential predators. We tested eight species of North American pit vipers for behavioural responses to an ophiophagous (snake-eating) predator, the common kingsnake, Lampropeltis getula. Kingsnakes have a substance in their skin that is recognized by crotalines, which react with a series of defensive responses including, but not limited to, avoidance, fleeing, body bridging and head hiding. The vomeronasal duct of the pit vipers was sutured closed to determine the role of this organ in detection of kingsnakes. Pit vipers with intact and sutured vomeronasal ducts were tested in a neutral cage with a kingsnake and monitored for behavioural responses. Results demonstrated that the vomeronasal organ is important in the recognition of kingsnakes by pit vipers and raises doubts that any other sense plays a major role in this behaviour. Copyright 1999 The Association for the Study of Animal Behaviour. PMID:10413540

Miller; Gutzke

1999-07-01

10

Antitumor effect of Bothrops jararaca venom.  

PubMed Central

Many experimental studies have been carried out using snake venoms for the treatment of animal tumors, with controversial results. While some authors have reported an antitumor effect of treatment with specific snake venom fractions, others have reported no effects after this treatment. The aim of this study was to evaluate the effect of Bothrops jararaca venom (BjV) on Ehrlich ascites tumor (EAT) cells in vivo and in vitro. In the in vivo study, Swiss mice were inoculated with EAT cells by the intraperitoneal (i.p.) route and treated with BjV venom (0.4 mg/kg, i.p.), on the 1st, 4th, 7th, 10th, and 13th days. Mice were evaluated for total and differential cells number on the 2nd, 5th, 8th, 11th and 14th days. The survival time was also evaluated after 60 days of tumor growth. In the in vitro study, EAT and normal peritoneal cells were cultivated in the presence of different BjV concentrations (2.5, 5.0, 10.0, 20.0, 40.0, and 80 microg) and viability was verified after 3, 6, 12 and 24 h of cultivation. Results were analyzed statistically by the Kruskal-Wallis and Tukey tests at the 5% level of significance. It was observed that in vivo treatment with BjV induced tumor growth inhibition, increased animal survival time, decreased mortality, increased the influx of polymorphonuclear leukocytes on the early stages of tumor growth, and did not affect the mononuclear cells number. In vitro treatment with BjV produced a dose-dependent toxic effect on EAT and peritoneal cells, with higher effects against peritoneal cells. Taken together, our results demonstrate that BjV has an important antitumor effect. This is the first report showing this in vivo effect for this venom. PMID:12061431

da Silva, Reinaldo J; da Silva, Marcia G; Vilela, Lizia C; Fecchio, Denise

2002-01-01

11

Agathos Daimon and the Asklepian serpent.  

PubMed

Much conjecture abounds about the origin of the Asklepian serpent of healing, this latter the universal metonym for curative medicine. Iconographic evidence of Asklepios with his staff-entwined serpent exists from Hippocratic times. Many theories exist about the origin of this reptilian symbol of curative medicine. Speculation has ranged from the skin-shed serpent emergent in new and robust health to putative associations with earlier Egyptian and Babylonian anguine (snake) symbols of life-determining power. Other scholars have drawn attention to the Palaeolithic, Neolithic and later Bronze-Age associations with serpent veneration in the context of rain and fertility religious invocations in India; and in many other cultures. In the South Pacific, in Australia and in Central and South America, serpents were regarded as spirits of the earth, often chthonian spirits who possessed life-giving powers. In Chaldean and Arabic etymology, the words for "serpent" and "life" have a synergy. In Classical Greece, the Agathos Daimon was literally the "noble spirit", a personal companion spirit ensuing health and good fortune. The Agathos Daimon was portrayed in iconography as a serpent, or as a fit and comely youth. This paper conjectures that the serpentine Agathos Daimon was one origin of the Asklepian symbol of medicine, portrayed as the serpent associated of the Homeric Asklepios. In later Roman times, the Agathos Daimon was transliterated to the agathodaemon, a protective companion spirit both of individuals and of the homes in which they lived. This benign resident spirit featured prominently in Roman art and was a common feature as a protective household spirit in first century homes at both Pompeii and Herculaneum. The agathodaemon motif also featured on Roman coins, such as bronze diobols of Antoninus Plus (138 - 161 A.D.) from Alexandrian mints in Egypt. In the twenty-first century, the serpentine Agathos Daimon is honoured not only as the symbol of medicine; but is daily acknowledged in toasts to "Good Health". PMID:22043596

Pearn, John

2011-06-01

12

Appraisal of Antiophidic Potential of Marine Sponges against Bothrops jararaca and Lachesis muta Venom  

PubMed Central

Snakebites are a health problem in many countries due to the high incidence of such accidents. Antivenom treatment has regularly been used for more than a century, however, this does not neutralize tissue damage and may even increase the severity and morbidity of accidents. Thus, it has been relevant to search for new strategies to improve antiserum therapy, and a variety of molecules from natural sources with antiophidian properties have been reported. In this paper, we analyzed the ability of ten extracts from marine sponges (Amphimedon viridis, Aplysina fulva, Chondrosia collectrix, Desmapsamma anchorata, Dysidea etheria, Hymeniacidon heliophila, Mycale angulosa, Petromica citrina, Polymastia janeirensis, and Tedania ignis) to inhibit the effects caused by Bothrops jararaca and Lachesis muta venom. All sponge extracts inhibited proteolysis and hemolysis induced by both snake venoms, except H. heliophila, which failed to inhibit any biological activity. P. citrina inhibited lethality, hemorrhage, plasma clotting, and hemolysis induced by B. jararaca or L. muta. Moreover, other sponges inhibited hemorrhage induced only by B. jararaca. We conclude that Brazilian sponges may be a useful aid in the treatment of snakebites caused by L. muta and B. jararaca and therefore have potential for the discovery of molecules with antiophidian properties. PMID:24141284

Faioli, Camila Nunes; Domingos, Thaisa Francielle Souza; de Oliveira, Eduardo Coriolano; Sanchez, Eladio Flores; Ribeiro, Suzi; Muricy, Guilherme; Fuly, Andre Lopes

2013-01-01

13

Richard Owen and the sea-serpent.  

PubMed

The well known naturalist, Richard Owen, had a career long engagement with monstrous creatures. In the 1830s he famously christened large fossil reptiles, Dinosauria. He investigated fossil marine reptiles as well as the giant moa. He also looked into the sea-serpents and sea monsters then drawing wide public attention. He actively collected letters and analyzed correspondence on the topic, consulted with the admiralty on reports of Royal Navy encounters and sightings, and commented in the public press. He concluded that such reports were based upon misidentifications of whales and other large marine mammals, and not run-ins with mythological creatures. His work on the sea-serpent shows that rather than discount the idea out of hand, a number of high profile naturalists were intrigued by monsters and attempted to understand what they were. His work is key to understanding the skepticism over monsters held by modern mainstream science. This skepticism opened the field to later amateur investigators. PMID:22305471

Regal, Brian

2012-06-01

14

Bothrops jararaca Peptide with AntiHypertensive Action Normalizes Endothelium Dysfunction Involved in Physiopathology of Preeclampsia  

Microsoft Academic Search

Preeclampsia, a pregnancy-specific syndrome characterized by hypertension, proteinuria and edema, is a major cause of fetal and maternal morbidity and mortality especially in developing countries. Bj-PRO-10c, a proline-rich peptide isolated from Bothrops jararaca venom, has been attributed with potent anti-hypertensive effects. Recently, we have shown that Bj-PRO-10c-induced anti-hypertensive actions involved NO production in spontaneous hypertensive rats. Using in vitro studies

Gabriel Benedetti; Katia L. P. Morais; Juliano R. Guerreiro; Eduardo Fontana de Oliveira; Mara Sandra Hoshida; Leandro Oliveira; Nelson Sass; Ivo Lebrun; Henning Ulrich; Claudiana Lameu; Antonio Carlos Martins de Camargo

2011-01-01

15

A Transcriptomic View of the Proteome Variability of Newborn and Adult Bothrops jararaca Snake Venoms  

PubMed Central

Background Snake bite is a neglected public health problem in communities in rural areas of several countries. Bothrops jararaca causes many snake bites in Brazil and previous studies have demonstrated that the pharmacological activities displayed by its venom undergo a significant ontogenetic shift. Similarly, the venom proteome of B. jararaca exhibits a considerable variation upon neonate to adult transition, which is associated with changes in diet from ectothermic prey in early life to endothermic prey in adulthood. Moreover, it has been shown that the Brazilian commercial antibothropic antivenom, which is produced by immunization with adult venom, is less effective in neutralizing newborn venom effects. On the other hand, venom gland transcripts of newborn snakes are poorly known since all transcriptomic studies have been carried out using mRNA from adult specimens. Methods/Principal Findings Here we analyzed venom gland cDNA libraries of newborn and adult B. jararaca in order to evaluate whether the variability demonstrated for its venom proteome and pharmacological activities was correlated with differences in the structure of toxin transcripts. The analysis revealed that the variability in B. jararaca venom gland transcriptomes is quantitative, as illustrated by the very high content of metalloproteinases in the newborn venom glands. Moreover, the variability is also characterized by the structural diversity of SVMP precursors found in newborn and adult transcriptomes. In the adult transcriptome, however, the content of metalloproteinase precursors considerably diminishes and the number of transcripts of serine proteinases, C-type lectins and bradykinin-potentiating peptides increase. Moreover, the comparison of the content of ESTs encoding toxins in adult male and female venom glands showed some gender-related differences. Conclusions/Significance We demonstrate a substantial shift in toxin transcripts upon snake development and a marked decrease in the metalloproteinase P-III/P-I class ratio which are correlated with changes in the venom proteome complexity and pharmacological activities. PMID:22428077

Zelanis, Andre; Andrade-Silva, Debora; Rocha, Marisa M.; Furtado, Maria F.; Serrano, Solange M. T.; Junqueira-de-Azevedo, Inacio L. M.; Ho, Paulo Lee

2012-01-01

16

Proteomic Analysis of the Ontogenetic Variability in Plasma Composition of Juvenile and Adult Bothrops jararaca Snakes  

PubMed Central

The ontogenetic variability in venom composition of some snake genera, including Bothrops, as well as the biological implications of such variability and the search of new molecules that can neutralize the toxic components of these venoms have been the subject of many studies. Thus, considering the resistance of Bothrops jararaca to the toxic action of its own venom and the ontogenetic variability in venom composition described in this species, a comparative study of the plasma composition of juvenile and adult B. jararaca snakes was performed through a proteomic approach based on 2D electrophoresis and mass spectrometry, which allowed the identification of proteins that might be present at different levels during ontogenetic development. Among the proteins identified by mass spectrometry, antihemorrhagic factor Bj46a was found only in adult plasma. Moreover, two spots identified as phospholipase A2 inhibitors were significantly increased in juvenile plasma, which can be related to the higher catalytic PLA2 activity shown by juvenile venom in comparison to that of adult snakes. This work shows the ontogenetic variability of B. jararaca plasma, and that these changes can be related to the ontogenetic variability described in its venom. PMID:24062950

de Morais-Zani, Karen; Grego, Kathleen Fernandes; Tanaka, Aparecida Sadae; Tanaka-Azevedo, Anita Mitico

2013-01-01

17

Do Sidewinder Rattlesnakes (Crotalus cerastes, Viperidae) Cease Feeding During the Breeding Season?  

E-print Network

Do Sidewinder Rattlesnakes (Crotalus cerastes, Viperidae) Cease Feeding During the Breeding Season? Michael M. Webber1 , Xavier Glaudas1 , and Javier A. Rodri´guez-Robles1 Seasonal aphagia (a lack and male Crotalus cerastes (Sidewinders) exhibit seasonal aphagia during the reproductive season. We

Rodríguez, Javier A.

18

Lachesis muta (Viperidae) cDNAs Reveal Diverging Pit Viper Molecules and Scaffolds Typical of Cobra (Elapidae) Venoms: Implications for Snake Toxin Repertoire Evolution  

Microsoft Academic Search

Efforts to describe toxins from the two major families of venomous snakes (Viperidae and Elapidae) usually reveal proteins belonging to few structural types, particular of each family. Here we carried on an effort to determine uncommon cDNAs that represent possible new toxins from Lachesis muta (Viperidae). In addition to nine classes of typical toxins, atypical molecules never observed in the

Inácio L. M. Junqueira-de-Azevedo; Ana T. C. Ching; Eneas Carvalho; Fernanda Faria; Milton Y. Nishiyama Jr; Paulo L. Ho; Marcelo R. V. Diniz

2006-01-01

19

Google Explores the 10th Mermaids and Sea Serpents  

E-print Network

Google Explores the 10th Planet Mermaids and Sea Serpents NASA has spent tens of billions of Planet Earth and Planet Ocean is highlighted by the computer program and image repository Google Earth altimeter data may be used to predict bathymetry at a scale of 6-9 km. The ability to use Google Earth below

Vernon, Frank

20

Antivenom Effects of 1,2,3-Triazoles against Bothrops jararaca and Lachesis muta Snakes  

PubMed Central

Snake venoms are complex mixtures of proteins of both enzymes and nonenzymes, which are responsible for producing several biological effects. Human envenomation by snake bites particularly those of the viperid family induces a complex pathophysiological picture characterized by spectacular changes in hemostasis and frequently hemorrhage is also seen. The present work reports the ability of six of a series of 1,2,3-triazole derivatives to inhibit some pharmacological effects caused by the venoms of Bothrops jararaca and Lachesis muta. In vitro assays showed that these compounds were impaired in a concentration-dependent manner, the fibrinogen or plasma clotting, hemolysis, and proteolysis produced by both venoms. Moreover, these compounds inhibited biological effects in vivo as well. Mice treated with these compounds were fully protected from hemorrhagic lesions caused by such venoms. But, only the B. jararaca edema-inducing activity was neutralized by the triazoles. So the inhibitory effect of triazoles derivatives against some in vitro and in vivo biological assays of snake venoms points to promising aspects that may indicate them as molecular models to improve the production of effective antivenom or to complement antivenom neutralization, especially the local pathological effects, which are partially neutralized by antivenoms. PMID:23710441

Domingos, Thaisa F. S.; Moura, Laura de A.; Carvalho, Carla; Campos, Vinicius R.; Jordao, Alessandro K.; Cunha, Anna C.; Ferreira, Vitor F.; de Souza, Maria Cecilia B. V.; Sanchez, Eladio F.; Fuly, Andre L.

2013-01-01

21

The defensive strike of five species of lanceheads of the genus Bothrops (Viperidae).  

PubMed

We studied the defensive strike of one species of each of five recognized lineages within the genus Bothrops, namely, B. alternatus, B. jararaca, B. jararacussu, B. moojeni and B. pauloensis. The defensive strike of the studied species was in general similar to that of Crotalus viridis and C. atrox, but some important differences were observed. Bothrops alternatus and B. pauloensis struck preferentially from a tight body posture, whereas B. jararaca and B. moojeni from a loose body posture. Defensive strikes were either true or false (during the latter, the mouth remains closed or partially open). Almost all strikes were successful; only on a few occasions snakes missed their target (flawed strikes). Strike variables were very conservative among the five species, especially strike distance and height, and one possible explanation may be related to constraints imposed on strike variables as a way of increasing strike accuracy. PMID:17876444

Araújo, M S; Martins, M

2007-05-01

22

Comparative analysis of viperidae venoms antibacterial profile: a short communication for proteomics.  

PubMed

Bacterial infections involving multidrug-resistant strains are one of the ten leading causes of death and an important health problem in need for new antibacterial sources and agents. Herein, we tested and compared four snake venoms (Agkistrodon rhodostoma, Bothrops jararaca, B. atrox and Lachesis muta) against 10 Gram-positive and Gram-negative drug-resistant clinical bacteria strains to identify them as new sources of potential antibacterial molecules. Our data revealed that, as efficient as some antibiotics currently on the market (minimal inhibitory concentration (MIC) = 1-32 ?g mL(-1)), A. rhodostoma and B. atrox venoms were active against Staphylococcus epidermidis and Enterococcus faecalis (MIC = 4.5 ?g mL(-1)), while B. jararaca inhibited S. aureus growth (MIC = 13 ?g ml(-1)). As genomic and proteomic technologies are improving and developing rapidly, our results suggested that A. rhodostoma, B. atrox and B. jararaca venoms and glands are feasible sources for searching antimicrobial prototypes for future design new antibiotics against drug-resistant clinical bacteria. They also point to an additional perspective to fully identify the pharmacological potential of these venoms by using different techniques. PMID:18955360

Ferreira, Bruno L; Santos, Dilvani O; Dos Santos, André Luis; Rodrigues, Carlos R; de Freitas, Cícero C; Cabral, Lúcio M; Castro, Helena C

2011-01-01

23

Ancient scientific basis of the "great serpent" from historical evidence  

NASA Technical Reports Server (NTRS)

Zoological data and a growing mythology contributed to ancient Western knowledge about large serpents. Yet little modern attention has been paid to the sources, transmission, and receipt in the early Middle Ages of the ancients' information concerning "dragons" and "sea serpents." Real animals--primarily pythons and whales--lie behind the ancient stories. Other animals, conflations of different animals, simple misunderstandings, and willful exaggerations are found to account for the fanciful embellishments, but primitive myths played no significant role in this process during classical times. The expedition of Alexander the Great into India (327-325 B.C.) and the Bagradas River incident in North Africa (256 B.C.) had enormous repercussions on the development of serpent lore. Credible evidence is found for the presence of ancient populations of pythons living along the North African coast west of Egypt and along the coast of the Arabian Sea between the Indus River and the Strait of Hormuz--places where they no longer exist today. The maximum sizes of ancient pythons may have been greater than those of today's specimens.

Stothers, Richard B.

2004-01-01

24

Ancient scientific basis of the "great serpent" from historical evidence.  

PubMed

Zoological data and a growing mythology contributed to ancient Western knowledge about large serpents. Yet little modern attention has been paid to the sources, transmission, and receipt in the early Middle Ages of the ancients' information concerning "dragons" and "sea serpents." Real animals--primarily pythons and whales--lie behind the ancient stories. Other animals, conflations of different animals, simple misunderstandings, and willful exaggerations are found to account for the fanciful embellishments, but primitive myths played no significant role in this process during classical times. The expedition of Alexander the Great into India (327-325 B.C.) and the Bagradas River incident in North Africa (256 B.C.) had enormous repercussions on the development of serpent lore. Credible evidence is found for the presence of ancient populations of pythons living along the North African coast west of Egypt and along the coast of the Arabian Sea between the Indus River and the Strait of Hormuz--places where they no longer exist today. The maximum sizes of ancient pythons may have been greater than those of today's specimens. PMID:15490966

Stothers, Richard B

2004-06-01

25

Comparative pathology of parasitic infections in free-ranging and captive pit vipers (Bothrops jararaca).  

PubMed

Between June 1997 and May 1998, 47 pit vipers (Bothrops jararaca) (Group A) were euthanased when they were brought to the Instituto Butantan by farmers, and examined postmortem; during the same period, 91 snakes of the same species (group B) were examined after they had died in an outdoor serpentarium. The majority of the parasites encountered were nematodes; lungworms, Rhabdias vellardi, and the intestinal hookworm Kalicephalus inermis were the most common. Some of the snakes in group A were heavily infested, but their lesions were mild, whereas in group B the parasites were generally accompanied by severe lesions. The parasites with a direct life cycle were more common than those with obligatory intermediate hosts, and the snakes were more commonly infected during the hotter and more humid seasons. PMID:15144001

Grego, K Fernandes; Gardiner, C H; Catão-Dias, J L

2004-05-01

26

Two-Dimensional NMR of Velocity Exchange: VEXSY and SERPENT  

NASA Astrophysics Data System (ADS)

Two different multidimensional pulsed field gradient sequences are compared which have the purpose of correlating spin displacements in different time intervals with each other. The simplest possible sequence, three-pulse SERPENT, measures displacements in two interleaved time intervals, while in VEXSY, consisting of two independent pairs of gradient pulses separated by a mixing time, displacements during the two encoding intervals are compared to each other. The formalism for both sequences is discussed in q space and in displacement space and common features as well as differences between the two types of experiments are highlighted, employing the particular case of the concurrent VEXSY scheme which allows treatment according to both formalisms.

Blümich, B.; Callaghan, P. T.; Damion, R. A.; Han, S.; Khrapitchev, A. A.; Packer, K. J.; Stapf, S.

2001-09-01

27

Two-dimensional NMR of velocity exchange: VEXSY and SERPENT.  

PubMed

Two different multidimensional pulsed field gradient sequences are compared which have the purpose of correlating spin displacements in different time intervals with each other. The simplest possible sequence, three-pulse SERPENT, measures displacements in two interleaved time intervals, while in VEXSY, consisting of two independent pairs of gradient pulses separated by a mixing time, displacements during the two encoding intervals are compared to each other. The formalism for both sequences is discussed in q space and in displacement space and common features as well as differences between the two types of experiments are highlighted, employing the particular case of the concurrent VEXSY scheme which allows treatment according to both formalisms. PMID:11531375

Blümich, B; Callaghan, P T; Damion, R A; Han, S; Khrapitchev, A A; Packer, K J; Stapf, S

2001-09-01

28

Characterization of two hemorrhagic factors isolated from the venom of Bothrops neuwiedi (jararaca pintada).  

PubMed

Two hemorrhagic factors were isolated from the venom of Bothrops neuwiedi (jararaca pintada) by ammonium sulfate precipitation followed by chromatography on DEAE-Sephadex A-50 and DEAE-cellulose DE-32, gel filtration on Sephadex G-100 and polyacrylamide-gel electrophoresis. These factors were named neuwiedi hemorrhagic factors NHFa and NHFb. They are acidic proteins of pI 4.2-4.3 and consist of single polypeptide chains of molecular weights 46,000 and 58,000, respectively, as determined by sodium dodecyl sulfate polyacrylamide-gel electrophoresis. The hemorrhagic activity of NHFb is 23 times stronger than that of NHFa. Both hydrolyse casein, although NHFa is about 20 times more active than NHFb. They are metalloproteins inhibited by EDTA and 1,10-phenanthroline. NHFa and NHFb are serologically closely related antigens. These two factors are recognized as identical antigens by horse serum against crude Bothrops neuwiedi venom. However, the rabbit specific antiserum was able to differentiate NHFa from NHFb showing, nevertheless, that they have common determinants apart from specific determinants for each one. PMID:6427978

Mandelbaum, F R; Assakura, M T; Reichl, A P

1984-01-01

29

The Serpent Monte Carlo Code: Status, Development and Applications in 2013  

NASA Astrophysics Data System (ADS)

The Serpent Monte Carlo reactor physics burnup calculation code has been developed at VTT Technical Research Centre of Finland since 2004, and is currently used in 100 universities and research organizations around the world. This paper presents the brief history of the project, together with the currently available methods and capabilities and plans for future work. Typical user applications are introduced in the form of a summary review on Serpent-related publications over the past few years.

Leppänen, Jaakko; Pusa, Maria; Viitanen, Tuomas; Valtavirta, Ville; Kaltiaisenaho, Toni

2014-06-01

30

[Phylogenetic relationships among Viperidae, Crotalinae based on mitochondrial 12S rRNA sequence variations].  

PubMed

This paper analyzed the phylogenetic relationships and classification of pit vipers (Viperidae, Crotalinae) based on mitochondrial 12S rRNA gene sequence variations. We have sequenced mtDNA 12S rRNA gene about 370 bp fragment from Gloydius saxatilis Emelianov, Gloydius shedaoensis Zhao, Gloydius ussurriensis (Emelianov), Trimeresurus stejnegeri Schmidt and Deinagkistrodon acutus, Gloydius brevicaudus (Stejneger) from two different localities, respectively. Combined with the sequence of Dinodon semicarinatus from GenBank, we have constructed two molecular phylogenetic trees using both Maximum-parsimony analysis and Neighbor-joining. Our results support the following conclusions: (1) Deinagkistrodon is a valid genus; (2) we also discussed the origin of Gloydius shedaoensis and showed it is a subspecies of Gloydius saxatilis; (3) Gloydius brevicaudsu and Gloydius ussurriensis are classified two species. PMID:11147345

Zhou, J L; Yao, Y G; Huang, M H; Yang, D T; Lü, S Q; Zhang, Y P

2000-01-01

31

N-terminal amino acid sequences and some characteristics of fibrinolytic/hemorrhagic metalloproteinases purified from Bothrops jararaca venom.  

PubMed

We determined the N-terminal amino acid sequences of the fibrinolytic/hemorrhagic metalloproteinases (jararafibrases I, III and IV) purified from Bothrops jararaca venom. The N-terminal amino acid sequences of jararafibrase I and its degradation products were identical to those of jararhagin, another hemorrhagic metalloproteinase purified from the same snake venom. Together with enzymatic and immunological properties, we concluded that those two enzymes are identical. The N-terminal amino acid sequence of jararafibrase III was quite similar to C-type lectin isolated from Crotalus atrox, and the protein had a hemagglutinating activity on intact rat red blood cells. PMID:12165326

Maruyama, Masugi; Sugiki, Masahiko; Anai, Keita; Yoshida, Etsuo

2002-08-01

32

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

PubMed

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. PMID:21967222

Abo-Eleneen, Rasha E; Allam, Ahmed A

2011-10-01

33

Aqueous Leaf Extract of Jatropha gossypiifolia L. (Euphorbiaceae) Inhibits Enzymatic and Biological Actions of Bothrops jararaca Snake Venom  

PubMed Central

Snakebites are a serious public health problem due their high morbi-mortality. The main available specific treatment is the antivenom serum therapy, which has some disadvantages, such as poor neutralization of local effects, risk of immunological reactions, high cost and difficult access in some regions. In this context, the search for alternative therapies is relevant. Therefore, the aim of this study was to evaluate the antiophidic properties of Jatropha gossypiifolia, a medicinal plant used in folk medicine to treat snakebites. The aqueous leaf extract of the plant was prepared by decoction and phytochemical analysis revealed the presence of sugars, alkaloids, flavonoids, tannins, terpenes and/or steroids and proteins. The extract was able to inhibit enzymatic and biologic activities induced by Bothrops jararaca snake venom in vitro and in vivo. The blood incoagulability was efficiently inhibited by the extract by oral route. The hemorrhagic and edematogenic local effects were also inhibited, the former by up to 56% and the latter by 100%, in animals treated with extract by oral and intraperitoneal routes, respectively. The inhibition of myotoxic action of B. jararaca reached almost 100%. According to enzymatic tests performed, it is possible to suggest that the antiophidic activity may be due an inhibitory action upon snake venom metalloproteinases (SVMPs) and/or serine proteinases (SVSPs), including fibrinogenolytic enzymes, clotting factors activators and thrombin like enzymes (SVTLEs), as well upon catalytically inactive phospholipases A2 (Lys49 PLA2). Anti-inflammatory activity, at least partially, could also be related to the inhibition of local effects. Additionally, protein precipitating and antioxidant activities may also be important features contributing to the activity presented. In conclusion, the results demonstrate the potential antiophidic activity of J. gossypiifolia extract, including its significant action upon local effects, suggesting that it may be used as a new source of bioactive molecules against bothropic venom. PMID:25126759

Felix-Silva, Juliana; Souza, Thiago; Menezes, Yamara A. S.; Cabral, Barbara; Camara, Rafael B. G.; Silva-Junior, Arnobio A.; Rocha, Hugo A. O.; Rebecchi, Ivanise M. M.; Zucolotto, Silvana M.; Fernandes-Pedrosa, Matheus F.

2014-01-01

34

Lachesis muta (Viperidae) cDNAs Reveal Diverging Pit Viper Molecules and Scaffolds Typical of Cobra (Elapidae) Venoms: Implications for Snake Toxin Repertoire Evolution  

PubMed Central

Efforts to describe toxins from the two major families of venomous snakes (Viperidae and Elapidae) usually reveal proteins belonging to few structural types, particular of each family. Here we carried on an effort to determine uncommon cDNAs that represent possible new toxins from Lachesis muta (Viperidae). In addition to nine classes of typical toxins, atypical molecules never observed in the hundreds of Viperidae snakes studied so far are highly expressed: a diverging C-type lectin that is related to Viperidae toxins but appears to be independently originated; an ohanin-like toxin, which would be the third member of the most recently described class of Elapidae toxins, related to human butyrophilin and B30.2 proteins; and a 3FTx-like toxin, a new member of the widely studied three-finger family of proteins, which includes major Elapidae neurotoxins and CD59 antigen. The presence of these common and uncommon molecules suggests that the repertoire of toxins could be more conserved between families than has been considered, and their features indicate a dynamic process of venom evolution through molecular mechanisms, such as multiple recruitments of important scaffolds and domain exchange between paralogs, always keeping a minimalist nature in most toxin structures in opposition to their nontoxin counterparts. PMID:16582429

Junqueira-de-Azevedo, Inacio L. M.; Ching, Ana T. C.; Carvalho, Eneas; Faria, Fernanda; Nishiyama, Milton Y.; Ho, Paulo L.; Diniz, Marcelo R. V.

2006-01-01

35

Post-ovipositional development of the monocled cobra, Naja kaouthia (Serpentes: Elapidae)  

E-print Network

Post-ovipositional development of the monocled cobra, Naja kaouthia (Serpentes: Elapidae) Kate development between oviposition and hatching of the monocled cobra, Naja kaouthia, is described. Ten deve- cled cobras (Naja kaouthia). Ten clutches, totaling ap- proximately 70 eggs, were obtained from

Jackson, Kate

36

Brain nitric oxide production by a proline-rich decapeptide from Bothrops jararaca venom improves baroreflex sensitivity of spontaneously hypertensive rats  

Microsoft Academic Search

Baroreflex sensitivity is disturbed in many people with cardiovascular diseases such as hypertension. Brain deficiency of nitric oxide (NO), which is synthesized by NO synthase (NOS) in the citrulline–NO cycle (with argininosuccinate synthase (ASS) activity being the rate-limiting step), contributes to impaired baroreflex. We recently showed that a decapeptide isolated from Bothrops jararaca snake venom, denoted Bj-PRO-10c, exerts powerful and

Claudiana Lameu; Vera Pontieri; Juliano R Guerreiro; Eduardo F Oliveira; Carlos Alberto da Silva; Joyce M Giglio; Robson L Melo; Ruy R Campos; Antonio Carlos Martins de Camargo; Henning Ulrich

2010-01-01

37

SERPent: Automated reduction and RFI-mitigation software for e-MERLIN  

NASA Astrophysics Data System (ADS)

The Scripted E-merlin Rfi-mitigation PipelinE for iNTerferometry (SERPent) is an automated reduction and RFI-mitigation procedure utilising the SumThreshold methodology (Offringa et al., 2010a), originally developed for the LOFAR pipeline. SERPent is written in the Parseltongue language enabling interaction with the Astronomical Image Processing Software (AIPS) program. Moreover, SERPent is a simple ‘out of the box’ Python script, which is easy to set up and is free of compilers. In addition to the flagging of RFI affected visibilities, the script also flags antenna zero-amplitude dropouts and Lovell telescope phase calibrator stationary scans inherent to the e-MERLIN system. Both the flagging and computational performances of SERPent are presented here, for e-MERLIN commissioning datasets for both L-band (1.3-1.8 GHz) and C-band (4-8 GHz) observations. RFI typically amounts to <20%-25% for the more problematic L-band observations and <5% for the generally RFI quieter C-band. The level of RFI detection and flagging is more accurate and delicate than visual manual flagging, with the output immediately ready for AIPS calibration. SERPent is fully parallelised and has been tested on a range of computing systems. The current flagging rate is at 110 GB day-1 on a ‘high-end’ computer (16 CPUs, 100 GB memory) which amounts to ˜6.9 GB CPU-1 day-1, with an expected increase in performance when e-MERLIN has completed its commissioning. The refining of automated reduction and calibration procedures is essential for the e-MERLIN legacy projects and future interferometers such as the SKA and the associated pathfinders (MeerKAT and ASKAP), where the vast data sizes (>TB) make traditional astronomer interactions unfeasible.

Peck, Luke W.; Fenech, Danielle M.

2013-08-01

38

The GATA factor Serpent cross-regulates lozenge and u-shaped expression during Drosophila blood cell development  

PubMed Central

The Drosophila GATA factor Serpent interacts with the RUNX factor Lozenge to activate the crystal cell program, whereas SerpentNC binds the Friend of GATA protein U-shaped to limit crystal cell production. Here, we identified a lozenge minimal hematopoietic cis-regulatory module and showed that lozenge-lacZ reporter-gene expression was autoregulated by Serpent and Lozenge. We also showed that upregulation of u-shaped was delayed until after lozenge activation, consistent with our previous results that showed u-shaped expression in the crystal cell lineage is dependent on both Serpent and Lozenge. Together, these observations describe a feed forward regulatory motif, which controls the temporal expression of u-shaped. Finally, we showed that lozenge reporter-gene activity increased in a u-shaped mutant background and that forced expression of SerpentNC with U-shaped blocked lozenge- and u-shaped-lacZ reporter-gene activity. This is the first demonstration of GATA:FOG regulation of Runx and Fog gene expression. Moreover, these results identify components of a Serpent cross-regulatory sub-circuit that can modulate lozenge expression. Based on the sub-circuit design and the combinatorial control of crystal cell production, we present a model for the specification of a dynamic bi-potential regulatory state that contributes to the selection between a Lozenge-positive and Lozenge-negative state. PMID:17869239

Muratoglu, Selen; Hough, Barry; Mon, Soe T.; Fossett, Nancy

2007-01-01

39

Primary structure of two-chain botrocetin, a von Willebrand factor modulator purified from the venom of Bothrops jararaca.  

PubMed Central

The complete amino acid sequence and location of the disulfide bonds of two-chain botrocetin, which promotes platelet agglutination in the presence of von Willebrand factor, from venom of the snake Bothrops jararaca are presented. Sequences of the alpha and beta subunits were determined by analysis of peptides generated by digestion of the S-pyridylethylated protein with Achromobacter protease I or alpha-chymotrypsin and by chemical cleavage with cyanogen bromide or 2-(2'-nitrophenylsulfenyl)-3-methyl-3-bromoindolenine. Two-chain botrocetin is a heterodimer composed of the alpha subunit (consisting of 133 amino acid residues) and the beta subunit (consisting of 125 amino acid residues) held together by a disulfide bond. Seven disulfide bonds link half-cystine residues 2 to 13, 30 to 128, and 103 to 120 of the alpha subunit; 2 to 13, 30 to 121, and 98 to 113 of the beta subunit; and 80 of the alpha subunit to 75 of the beta subunit. In terms of amino acid sequence and disulfide bond location, two-chain botrocetin is homologous to echinoidin (a sea urchin lectin) and other C-type (Ca(2+)-dependent) lectins. PMID:8430107

Usami, Y; Fujimura, Y; Suzuki, M; Ozeki, Y; Nishio, K; Fukui, H; Titani, K

1993-01-01

40

An alternative micromethod to access the procoagulant activity of Bothrops jararaca venom and the efficacy of antivenom.  

PubMed

The assessment of the capacity of antivenoms to neutralize the lethal activity of snake venoms still relies largely on traditional rodent lethality assay (LD50). However, adequately validated in vitro tests should be introduced for assessing antivenom neutralizing capacity in plasma of immunized horses as well as for in-process quality control. The dynamic of fibrin formation in recalcified avian plasma samples is extremely slow, when compared to that presented by mammalian plasmas. In this study, we present one new coagulant assay, by performing dose-response curve after plotting the clotting time (CT) parameter of the ROTEM profile of recalcified chicken plasma samples (target) against semi-logarithmic doses of Bothrops jararaca venom (agonist), either in absence or in presence of the semi-logarithmic doses of anti-bothropic serum (ABS) (antagonist). The mean coagulant dose 50% (CD50) was defined as the quantity of venom (in ?g) which reduces CT to 900 s, between minimum and maximum responses. The CT induced by 5CD50 of the venom was used as the control for calculating the effective dose (ED) of each batch of ABS. ED was defined as the ABS dose (nanoliters, nL) at which CT induced by one amount of venom corresponding to 5CD50 is displaced to the maximum threshold (1800 s). Five batches of the ABS, previously assayed for their lethality neutralizing activity (ED50) were assayed. The correlation coefficient (r) between both in vitro (ED) and in vivo (ED50) values was 0.87 (p value < 0.05). We propose this micro method as highly sensitive for characterization and quantification of possible procoagulant activity of small doses of snake venoms (nanograms) and for detecting small doses (nanoliters) of specific antibodies against this effect in little volume samples of biological fluids. PMID:25128708

Oguiura, N; Kapronezai, J; Ribeiro, T; Rocha, M M T; Medeiros, C R; Marcelino, J R; Prezoto, B C

2014-11-01

41

Combining mitochondrial DNA sequences and morphological data to infer species boundaries: phylogeography of lanceheaded pitvipers in the Brazilian Atlantic forest, and the status of Bothrops pradoi (Squamata: Serpentes: Viperidae)  

Microsoft Academic Search

Phylogeographic studies using mitochondrial DNA sequence information are frequently used as the principal source of evidence to infer species boundaries. However, a critical analysis of further evidence is essential to test whether different haplotype clades identify different species. We demonstrate a hypothesis-testing approach, using a combination of phylogeographic methods, multivariate morphometrics and matrix association tests, to investi- gate species boundaries

G. P UORTO; M. D A G RACA; R. D. G. T HEAKSTON; R. S. T HORPE; D. A. W ARRELL; W. WUSTER

42

Contribution of metalloproteases, serine proteases and phospholipases A2 to the inflammatory reaction induced by Bothrops jararaca crude venom in mice.  

PubMed

Various toxins isolated from Bothrops snake venoms induce inflammatory reactions and have been claimed to contribute to the severity of local symptoms present in this envenomation. Notwithstanding, the relative participation of serine proteases, metalloproteases and phospholipases A(2) in the inflammatory reaction produced by crude Bothrops venoms is poorly understood. Herein, crude Bothrops jararaca venom was treated with phenylmethanesulfonyl fluoride (PMSF), 1,10-phenanthroline (oPhe), or p-bromophenacyl-bromide (p-BPB) to inhibit those classes of enzymes, respectively, and inflammatory parameters were evaluated and compared to those induced by the control crude venom. The intensity of edema and hyperalgesia/allodynia was remarkably reduced in animals administered with oPhe-treated venom. Leukocyte-endothelium interactions (LEI), such as adhesion and migration of leukocytes, were also modified at 2h and 24h. Edema and LEI parameters induced by p-BPB-treated venom were similar to those observed with the control venom, but hyperalgesia/allodynia was significantly lower. Inflammatory parameters induced by PMSF-treated venom were similar to those induced by the crude venom, except for a mild reduction in edema intensity. Our results indicate that metalloproteases have a pivotal role in the inflammatory reactions induced by B. jararaca venom, and phospholipases A(2) and serine proteases have a minor role. PMID:19646466

Zychar, Bianca Cestari; Dale, Camila Squazoni; Demarchi, Denise Soares; Gonçalves, Luis Roberto C

2010-01-01

43

The ecological distribution of Causus Wagler 1830 (Viperidae) in Nigeria, with special reference to C. resimus (Peters 1862) and C. lichtensteini (Jan 1859), two species rarely recorded from this country  

Microsoft Academic Search

New data for snakes of the genus Causus Wagler 1830 (Viperidae) are reported for Nigeria, with emphasis on their ecological distribution and biology. Causus rhombeatus (Lichtenstein 1823) was never observed during our long-term field study, and is probably a very rare species in Nigeria, confined to a small area in the north-east of the country. We confirmed that Causus maculatus

G. C. Akani; L. Luiselli; Z. Tooze; F. M. Angelici; C. Corti; M. A. L. Zuffi

2001-01-01

44

Potassic and sodic metasomatism in the Southern Province of the Canadian Shield: Evidence from the Paleoproterozoic Serpent Formation, Huronian Supergroup, Canada  

Microsoft Academic Search

Major element geochemistry, petrographic observations, and microprobe analyses of the Paleoproterozoic Serpent Formation, Huronian Supergroup, Canada, suggest that these strata experienced both potassium and sodium metasomatism. Major element data, plotted in Al2O3?CaO? + Na2O?K2O compositional space, form an array nearly identical to data from sub-Huronian paleosols reported elsewhere, suggesting that Serpent fluvial systems captured materials from entire weathering profiles. Potassium

C. M. Fedo; G. M. Young; H. W. Nesbitt; J. M. Hanchar

1997-01-01

45

Angiotensin-degrading serine peptidase: a new chymotrypsin-like activity in the venom of Bothrops jararaca partially blocked by the commercial antivenom.  

PubMed

Snakebite envenomation is considered a highly relevant public health hazard in South America, having an impact in terms of mortality and morbidity. In Brazil, Bothrops (sensu latu) poisoning is responsible for 90% of the snakebites and in patients treated at the Vital Brazil Hospital (Butantan Institute) this index reaches 97.5%. The objective of the present study was to analyze more specifically the ability of the antibothropic antivenom, produced by the Butantan Institute, São Paulo, Brazil, to neutralize metallo-and serine peptidases, known as the major toxins present in Bothrops jararaca venom. A set of Fret peptides (Free Ressonance Energy Transfer) was studied using the BjV (B. jararaca venom) and site-directed inhibitors PMSF, EDTA and 1,10-phenanthroline. Two substrates were reached to be used as specific tools for studies with metallo peptidases, Abz-FASSAQ-EDDnp, and the serine peptidases, Abz-RPPGFSPFRQ-EDDnp. In disagreement with the literature, the use of both substrates and the antibothropic serum showed a weak neutralization of the serine peptidases present in this venom and a strong neutralization of the metallo peptidases. In order to investigate possible mechanisms of action that have not yet been described for the serine peptidases from the BjV, the present study shows for the first time a new tyrosine-specific chymotrypsin-like and angiotensin-degrading serine peptidase activity, that was partially blocked by the antibothropic serum. In conclusion, the antivenom presented a good neutralization of metallo peptidases but not of serine peptidases, indicating that further studies about serine peptidases immunogenicity are necessary to improve the antibothropic serum. PMID:22093545

Kuniyoshi, Alexandre Kazuo; Rocha, Marisa; Cajado Carvalho, Daniela; Juliano, Maria Aparecida; Juliano Neto, Luiz; Tambourgi, Denise Vilarinho; Portaro, Fernanda Calheta Vieira

2012-01-01

46

A Novel Phospholipase A2, BJ-PLA2, from the Venom of the Snake Bothrops jararaca: Purification, Primary Structure Analysis, and Its Characterization as a Platelet-Aggregation-Inhibiting Factor  

Microsoft Academic Search

This paper describes the isolation and primary structure analysis of a new phospholipase A2 with platelet-aggregation-inhibiting activity from the venom of Bothrops jararaca. The protein, named BJ-PLA2, was isolated by means of ammonium sulfate precipitation and anion-exchange and reversed-phase chromatographies and behaved as a homogeneous single-chain protein on SDS–PAGE. Its amino acid sequence was determined by N-terminal sequencing and analysis

Solange M. T. Serrano; Antonia P. Reichl; Reinhard Mentele; Ennes A. Auerswald; Marcelo L. Santoro; Claudio A. M. Sampaio; Antonio C. M. Camargo; Marina T. Assakura

1999-01-01

47

2007 was an extremely busy year for the SERPENT project. We continued to carry out a high number of offshore missions, with  

E-print Network

up by the largest body of marine science researchers in the world. The year also saw some changes that you enjoy reading these highlights from 2007. The SERPENT Team Cover picture: A stunning image from & Education 22 Media & Events 24 Publications 25 Research Assistants & Students 27 New Partnerships 28 2007

National Oceanography Centre, Southampton

48

Epidemiology of venomous and semi-venomous snakebites (Ophidia: Viperidae, Colubridae) in the Kashan city of the Isfahan province in Central Iran  

PubMed Central

Background: Information on the epidemiology of venomous snake species responsible for envenomation to humans in Iran has not been well documented. In the Kashan city, venomous snakebite remains a recurring medical problem. Information providing the correct identification of snake species responsible for envenomation in this geographic region would be useful to regional medical clinics and personnel for the effective and optimal management of the patients. Materials and Methods: In this cross-sectional study, all patient data was collected from Kashan city and its suburbs. The specific data relating to the taxonomic identification of snakes responsible for envenomation were evaluated. A general approach to the diagnosis and management of patients was also provided. Snakes responsible for bites were transported to a laboratory, where their taxonomic classification was confirmed based on key anatomical features and morphological characteristics. Results: A total of 46 snakes were examined. Of these, 37 (80%) were non-venomous species, and 9 (20%) were identified as venomous. Seven of the nine venomous snake species (78%) were of the family Viperidae, and two specimens (22%) were in the family Colubridae. Specifically, the viperid species were Macrovipera lebetina obtusa, Pseudocerastes persicus, Pseudocerastes fieldi, and Echis carinatus. The two colubrid species were Malpolon monspessulanus insignitus and Psammophis schkari. Conclusion: Five different species of venomous snakes responsible for envenomation in the Kashan city region were confirmed. The viper, P. fieldi, was reported for the first time in the central part of Iran. PMID:24672563

Dehghani, Rouhullah; Mehrpour, Omid; Shahi, Morteza Panjeh; Jazayeri, Mehrdad; Karrari, Parissa; Keyler, Dan; Zamani, Nasim

2014-01-01

49

Discovery of microscopic evidence for shock metamorphism at the Serpent Mound structure, south-central Ohio: Confirmation of an origin by impact  

USGS Publications Warehouse

The origin of the Serpent Mound structure in south-central Ohio has been disputed for many years. Clearly, more evidence was needed to resolve the confusion concerning the origin of the Serpent Mound feature either by endogenic processes or by hypervelocity impact. A petrographic study of 21 samples taken from a core 903 m long drilled in the central uplift of the structure provides evidence of shock metamorphism in the form of multiple sets of planar deformation features in quartz grains, as well as the presence of clasts of altered impact-melt rock. Crystallographic orientations of the planar deformation features show maxima at the shock-characteristic planes of {101??3} and {101??2} and additional maxima at {101??1}, {213??1}, and {516??1}. Geochemical analyses of impact breccias show minor enrichments in the abundances of the siderophile elements Cr, Co, Ni, and Ir, indicating the presence of a minor meteoritic component.

Carlton, R.W.; Koeberl, C.; Baranoski, M.T.; SchuMacHer, G.A.

1998-01-01

50

Anesthesia with isoflurane and sevoflurane in the crested serpent eagle (Spilornis cheela hoya): minimum anesthetic concentration, physiological effects, hematocrit, plasma chemistry and behavioral effects.  

PubMed

The initial goal of this study was to determine the minimum anesthetic concentration (MAC) for isoflurane (ISO) and sevoflurane (SEVO) for the crested serpent eagle. Next, we compared the anesthetic effects of each on the physiological effects, hematocrit, plasma chemistry values and behavior in spontaneously breathing captive adult crested serpent eagles. Sixteen eagles were randomly allocated to two groups for anesthesia with ISO (n=8) or SEVO (n=8). First, we measured the MAC values of ISO and SEVO, and four weeks later, we investigated the effect of each on the physiological effects, hematocrit (HCT) and plasma chemistry values. The MAC values of ISO and SEVO for crested serpent eagles were 1.46 ± 0.30 and 2.03 ± 0.32%, respectively. The results revealed no significant differences between the two anesthetics in induction time, while time of extubation to recovery was significantly shorter with SEVO. A time-related increase in end-tidal CO? and decreases in body temperature and respiratory rates were observed during anesthesia with each anesthetic. There were no significant differences between the effect of the two anesthetics on heart rate, hematocrit, plasma chemistry values or respiration, although each caused minor respiration depression. We concluded that SEVO is a more effective inhalant agent than ISO for use in eagles, showing the most rapidest induction and recovery from anesthesia. PMID:23955396

Chan, Fang-Tse; Chang, Geng-Ruei; Wang, Hsien-Chi; Hsu, Tien-Huan

2013-12-30

51

Anesthesia with Isoflurane and Sevoflurane in the Crested Serpent Eagle (Spilornis cheela hoya): Minimum Anesthetic Concentration, Physiological Effects, Hematocrit, Plasma Chemistry and Behavioral Effects  

PubMed Central

ABSTRACT The initial goal of this study was to determine the minimum anesthetic concentration (MAC) for isoflurane (ISO) and sevoflurane (SEVO) for the crested serpent eagle. Next, we compared the anesthetic effects of each on the physiological effects, hematocrit, plasma chemistry values and behavior in spontaneously breathing captive adult crested serpent eagles. Sixteen eagles were randomly allocated to two groups for anesthesia with ISO (n=8) or SEVO (n=8). First, we measured the MAC values of ISO and SEVO, and four weeks later, we investigated the effect of each on the physiological effects, hematocrit (HCT) and plasma chemistry values. The MAC values of ISO and SEVO for crested serpent eagles were 1.46 ± 0.30 and 2.03 ± 0.32%, respectively. The results revealed no significant differences between the two anesthetics in induction time, while time of extubation to recovery was significantly shorter with SEVO. A time-related increase in end-tidal CO2 and decreases in body temperature and respiratory rates were observed during anesthesia with each anesthetic. There were no significant differences between the effect of the two anesthetics on heart rate, hematocrit, plasma chemistry values or respiration, although each caused minor respiration depression. We concluded that SEVO is a more effective inhalant agent than ISO for use in eagles, showing the most rapidest induction and recovery from anesthesia. PMID:23955396

CHAN, Fang-Tse; CHANG, Geng-Ruei; WANG, Hsien-Chi; HSU, Tien-Huan

2013-01-01

52

A new species of Caryospora Léger, 1904 (Apicomplexa: Eimeriidae) from the endangered Round Island boa Casarea dussumieri (Schlegel) (Serpentes: Bolyeridae) of Round Island, Mauritius: an endangered parasite?  

Microsoft Academic Search

A new species of Caryospora Léger, 1904 (Apicomplexa: Eimeriidae), C. durelli n. sp., is described from the endangered Round Island boa Casarea dussumieri (Schlegel) (Serpentes: Bolyeridae) from Round Island, Mauritius. Six of 11 hosts were infected. Oöcysts are spherical to\\u000a subspherical, 19.2 × 18.2 (17.5–21 × 16–21) ?m, n = 20, and have a shape index (mean length\\/mean width) of 1.05 (1.02–1.09).\\u000a The bi-layered wall is

Peter DaszakStanley; Stanley J. Ball; Daniel G. Streicker; Carl G. Jones; Keith R. Snow

2011-01-01

53

Combinatorial interactions of Serpent, Lozenge, and U-shaped regulate crystal cell lineage commitment during Drosophila hematopoiesis  

PubMed Central

The GATA factor Serpent (Srp) is required for hemocyte precursor formation during Drosophila hematopoiesis. These blood cell progenitors give rise to two distinct lineages within the developing embryo. Lozenge, a Runx protein homologue, and Glial cells missing-1 and -2 are essential for crystal cell and plasmatocyte production, respectively. In contrast U-shaped, a Friend of GATA class factor, antagonizes crystal cell formation. Here we show that Srp, Lozenge, and U-shaped interact in different combinations to regulate crystal cell lineage commitment. Coexpression of Srp and Lozenge synergistically activated the crystal cell program in both embryonic and larval stages. Furthermore, expression of Lozenge and SrpNC, a Srp isoform with N- and C-terminal zinc fingers, inhibited u-shaped expression, indicating that crystal cell activation coincided with the down-regulation of this repressor-encoding gene. In contrast, whereas U-shaped and SrpNC together blocked crystal cell production, coexpression of U-shaped with noninteracting Srp proteins failed to prevent overproduction of this hemocyte population. Such results indicated that U-shaped and SrpNC must interact to block crystal cell production. Taken together, these studies show that the specialized SrpNC isoform plays a pivotal role during crystal cell lineage commitment, acting as an activator or repressor depending on the availability of specific transcriptional coregulators. These findings provide definitive proof of the combinatorial regulation of hematopoiesis in Drosophila and an in vivo demonstration of GATA and Runx functional interaction in a blood cell commitment program. PMID:14504400

Fossett, Nancy; Hyman, Kristy; Gajewski, Kathleen; Orkin, Stuart H.; Schulz, Robert A.

2003-01-01

54

The Descent of the Serpent: Using a Successful Ancient Solar Observatories Webcast from Chichen Itza to Highlight Space Weather Research  

NASA Astrophysics Data System (ADS)

Over the past seven years, NASA's Sun-Earth Connection Education Forum has sponsored and coordinated education and public outreach events to highlight NASA's heliophysics research and discoveries. Our strategy involves using celestial events, such as total solar eclipses and the Transit of Venus, as well as Sun-Earth Day during the March Equinox, to engage K-12 schools and the general public in space science activities, demonstrations, and interactions with space scientists. In collaboration with partners that include the Exploratorium and other museums, Ideum, NASA TV, NASA heliophysics missions, and others, we produce webcasts, other multi-media, and print resources for use by school and informal educators nation-wide and internationally. We provide training and professional development to K-12 educators, museum personnel, amateur astronomers, Girl Scout leaders, etc., so they can implement their own outreach programs taking advantage of our resources. A coordinated approach promotes multiple programs occurring each year under a common theme. As part of an Ancient Observatories theme in 2005, we have successfully featured solar alignments with ancient structures made by indigenous cultures that mark the equinoxes and/or solstices in cultural and historical parks in the Americas. In partnership with the Exploratorium, we produced broadcast-quality and webcast programming during the March equinox that shared heliophysics within a broad cultural context with formal and informal education audiences internationally. The program: "Descent of the Serpent" featured the light and shadow effect at sunset that takes place during the spring equinox at the Pyramid of El Castillo, in Chichén Itzá (México). This program made unique and authentic cultural connections to the knowledge of solar astronomy of the Maya, the living Mayan culture of today, and the importance of the Sun across the ages. We involved Sun-Earth Connection scientists, their missions, and research programs from México and the US to share NASA solar research with diverse audiences in the US and across the world, and to share how our dynamic Sun impacts the Earth and other planets in the solar system. During our presentation, we will highlight the strategies we used to successfully engage Hispanics of native heritage in heliophysics from all over the world.

Hawkins, I.; Higdon, R.; Cline, T.

2006-12-01

55

An extended version of the SERPENT-2 code to investigate fuel burn-up and core material evolution of the Molten Salt Fast Reactor  

NASA Astrophysics Data System (ADS)

In this work, the Monte Carlo burn-up code SERPENT-2 has been extended and employed to study the material isotopic evolution of the Molten Salt Fast Reactor (MSFR). This promising GEN-IV nuclear reactor concept features peculiar characteristics such as the on-line fuel reprocessing, which prevents the use of commonly available burn-up codes. Besides, the presence of circulating nuclear fuel and radioactive streams from the core to the reprocessing plant requires a precise knowledge of the fuel isotopic composition during the plant operation. The developed extension of SERPENT-2 directly takes into account the effects of on-line fuel reprocessing on burn-up calculations and features a reactivity control algorithm. It is here assessed against a dedicated version of the deterministic ERANOS-based EQL3D procedure (PSI-Switzerland) and adopted to analyze the MSFR fuel salt isotopic evolution. Particular attention is devoted to study the effects of reprocessing time constants and efficiencies on the conversion ratio and the molar concentration of elements relevant for solubility issues (e.g., trivalent actinides and lanthanides). Quantities of interest for fuel handling and safety issues are investigated, including decay heat and activities of hazardous isotopes (neutron and high energy gamma emitters) in the core and in the reprocessing stream. The radiotoxicity generation is also analyzed for the MSFR nominal conditions. The production of helium and the depletion in tungsten content due to nuclear reactions are calculated for the nickel-based alloy selected as reactor structural material of the MSFR. These preliminary evaluations can be helpful in studying the radiation damage of both the primary salt container and the axial reflectors.

Aufiero, M.; Cammi, A.; Fiorina, C.; Leppänen, J.; Luzzi, L.; Ricotti, M. E.

2013-10-01

56

A new species of Caryospora Léger, 1904 (Apicomplexa: Eimeriidae) from the endangered Round Island boa Casarea dussumieri (Schlegel) (Serpentes: Bolyeridae) of Round Island, Mauritius: an endangered parasite?  

PubMed

A new species of Caryospora Léger, 1904 (Apicomplexa: Eimeriidae), C. durelli n. sp., is described from the endangered Round Island boa Casarea dussumieri (Schlegel) (Serpentes: Bolyeridae) from Round Island, Mauritius. Six of 11 hosts were infected. Oöcysts are spherical to subspherical, 19.2 × 18.2 (17.5-21 × 16-21) ?m, n = 20, and have a shape index (mean length/mean width) of 1.05 (1.02-1.09). The bi-layered wall is composed of an outer layer of c.0.6 ?m thick and an inner layer of c.0.4 ?m thick. A micropyle, oöcyst residuum and polar granule are absent. Sporocysts are ellipsoidal, 14.7 × 11.0 (13-16 × 9.5-11.5) ?m, n = 20, and have a shape index of 1.33. Both Stieda and substieda bodies are present. The sporocyst residuum measures c.12 × 4.5 ?m, is surrounded by sporozoites and composed of numerous granules. Refractile bodies are present but not clearly visible. This is the first coccidian parasite reported from the family Bolyeridae and the first species of Caryospora durrelli [corrected] reported from the Mascarenes. Conservation issues concerning parasites of endangered host species are discussed. PMID:21279561

Daszak, Peter; Ball, Stanley J; Streicker, Daniel G; Jones, Carl G; Snow, Keith R

2011-02-01

57

A taxonomic revision of boas (serpentes: boidae).  

PubMed

Large molecular datasets including many species and loci have greatly improved our knowledge of snake phylogeny, particularly within the group including boas (Table 1). Recent taxonomic revisions using molecular phylogenies have clarified some of the previously contentious nomenclature of the group (Wilcox et al. 2002; Lawson et al. 2004; Burbrink 2005; Noonan & Chippindale 2006), resulting in a robust taxonomy that is mostly concordant with the phylogeny as currently known, which includes ~85% of described, extant species (Pyron et al. 2013; Reynolds et al. 2014). However, a few unresolved issues remain, related primarily to the rules of the International Code of Zoological Nomenclature (the Code hereafter) and the application of Linnaean ranks (International Commission on Zoological Nomenclature et al. 1999).  PMID:25112250

Pyron, R Alexander; Reynolds, R Graham; Burbrink, Frank T

2014-01-01

58

Body Size Evolution in Insular Speckled Rattlesnakes (Viperidae: Crotalus mitchellii)  

PubMed Central

Background Speckled rattlesnakes (Crotalus mitchellii) inhabit multiple islands off the coast of Baja California, Mexico. Two of the 14 known insular populations have been recognized as subspecies based primarily on body size divergence from putative mainland ancestral populations; however, a survey of body size variation from other islands occupied by these snakes has not been previously reported. We examined body size variation between island and mainland speckled rattlesnakes, and the relationship between body size and various island physical variables among 12 island populations. We also examined relative head size among giant, dwarfed, and mainland speckled rattlesnakes to determine whether allometric differences conformed to predictions of gape size (and indirectly body size) evolving in response to shifts in prey size. Methodology/Principal Findings Insular speckled rattlesnakes show considerable variation in body size when compared to mainland source subspecies. In addition to previously known instances of gigantism on Ángel de la Guarda and dwarfism on El Muerto, various degrees of body size decrease have occurred frequently in this taxon, with dwarfed rattlesnakes occurring mostly on small, recently isolated, land-bridge islands. Regression models using the Akaike information criterion (AIC) showed that mean SVL of insular populations was most strongly correlated with island area, suggesting the influence of selection for different body size optima for islands of different size. Allometric differences in head size of giant and dwarf rattlesnakes revealed patterns consistent with shifts to larger and smaller prey, respectively. Conclusions/Significance Our data provide the first example of a clear relationship between body size and island area in a squamate reptile species; among vertebrates this pattern has been previously documented in few insular mammals. This finding suggests that selection for body size is influenced by changes in community dynamics that are related to graded differences in area over what are otherwise similar bioclimatic conditions. We hypothesize that in this system shifts to larger prey, episodic saturation and depression of primary prey density, and predator release may have led to insular gigantism, and that shifts to smaller prey and increased reproductive efficiency in the presence of intense intraspecific competition may have led to insular dwarfism. PMID:20209105

Meik, Jesse M.; Lawing, A. Michelle; Pires-daSilva, Andre

2010-01-01

59

A bradykinin-potentiating peptide (BPP-10c) from Bothrops jararaca induces changes in seminiferous tubules  

PubMed Central

Background The testis-specific isoform of angiotensin-converting enzyme (tACE) is exclusively expressed in germ cells during spermatogenesis. Although the exact role of tACE in male fertility is unknown, it clearly plays a critical function in spermatogenesis. The dipeptidase domain of tACE is identical to the C-terminal catalytic domain of somatic ACE (sACE). Bradykinin potentiating peptides (BPPs) from snake venoms are the first natural sACE inhibitors described and their structure–activity relationship studies were the basis for the development of antihypertensive drugs such as captopril. In recent years, it has been showed that a number of BPPs – including BPP-10c – are able to distinguish between the N- and C-active sites of sACE, what is not applicable to captopril. Considering the similarity between tACE and sACE (and since BPPs are able to distinguish between the two active sites of sACE), the effects of the BPP-10c and captopril on the structure and function of the seminiferous epithelium were characterized in the present study. BPP-10c and captopril were administered in male Swiss mice by intraperitoneal injection (4.7 ?mol/kg for 15 days) and histological sections of testes were analyzed. Classification of seminiferous tubules and stage analysis were carried out for quantitative evaluation of germ cells of the seminiferous epithelium. The blood-testis barrier (BTB) permeability and distribution of claudin-1 in the seminiferous epithelium were analyzed by hypertonic fixative method and immunohistochemical analyses of testes, respectively. Results The morphology of seminiferous tubules from animals treated with BPP-10c showed an intense disruption of the epithelium, presence of atypical multinucleated cells in the lumen and degenerated germ cells in the adluminal compartment. BPP-10c led to an increase in the number of round spermatids and total support capacity of Sertoli cell in stages I, V, VII/VIII of the seminiferous epithelium cycle, without affecting BTB permeability and the distribution of claudin-1 in the seminiferous epithelium. Interestingly, no morphological or morphometric alterations were observed in animals treated with captopril. Conclusions The major finding of the present study was that BPP-10c, and not captopril, modifies spermatogenesis by causing hyperplasia of round spermatids in stages I, V, and VII/VIII of the spermatogenic cycle. PMID:24195771

2013-01-01

60

The rod and the serpent: history's ultimate healing symbol.  

PubMed

The snake has served as a medical emblem for more than 2400 years, since its association with the ancient Greek god of medicine and healing, Asclepius, in the 4th century BC. Its symbolic background can be traced further back to the worship of gods of earth's blossom in ancient Egypt and earth-related deities of the archaic period of Greek antiquity. It is featured entwined around a staff of knowledge and wisdom in most anaglyphs depicting Asclepius. The snake was impressed in the Old and the New Testament as well as in the Christian tradition as a symbol of sin, rejuvenation, death, resurrection, asthenia, and therapy. It is postulated that the double-snake motif was reintroduced by Renaissance philosophers as a medical emblem due to the symbolic connections of Hermes with deliverance and redemption. However, its use during the last two centuries seems to lack substantial historical background. The historical, mythological, and traditional retrospection of the snake's symbolism validates its appropriateness in the health-care field. PMID:20556606

Antoniou, Stavros A; Antoniou, George A; Learney, Robert; Granderath, Frank A; Antoniou, Athanasios I

2011-01-01

61

Geographic variation in Elaphe guttata (Linnaeus) (Serpentes: Colubridae  

E-print Network

to the synonymy of ~E1 he ~~1 and E. laeta to the synonymy of E. ~o . He pointed out that the type of S. ~1 etus is a )uvenile (45. 7 cm in total length) and that young E. obsoleta are very similar to E. ~emor i. The following year, Dowling (1952a) designated... in Utah and western Colorado represents a distinct race, E. laeta intermontanus. Dowling (1951a, b) placed this 21 for in *he synonymy of E. E ttat ~em i. Neill (1949) remarked on pattern variation in corn snakes in the eastern United States...

Thomas, Robert Allen

2012-06-07

62

The Pleistocene serpent Wonambi and the early evolution of snakes  

Microsoft Academic Search

The Madtsoiidae were medium sized to gigantic snakes with a fossil record extending from the mid-Cretaceous to the Pleistocene, and spanning Europe, Africa, Madagascar, South America and Australia. This widely distributed group survived for about 90 million years (70% of known ophidian history), and potentially provides important insights into the origin and early evolution of snakes. However, madtsoiids are known

John D. Scanlon; Michael S. Y. Lee

2000-01-01

63

Evolutionary relationships among the true vipers (Reptilia: Viperidae) inferred from mitochondrial DNA sequences.  

PubMed

Nucleotide sequences of mitochondrial cytochrome b and 16S rRNA genes, totaling 946 bp, were used to reconstruct a molecular phylogeny of 42 species of the subfamily Viperinae representing 12 of the 13 recognized genera. Maximum-parsimony and maximum-likelihood were used as methods for phylogeny reconstruction with and without a posteriori weighting. When representatives of the Causinae were taken as outgroup, five major monophyletic groups were consistently identified: Bitis, Cerastes, Echis, the Atherini (Atheris s.l.), and the Eurasian viperines. Proatheris was affiliated with Atheris, and Adenorhinos clustered within Atheris. The African Bitis consisted of at least three monophyletic groups: (i) the B. gabonica group, (ii) the B. caudalis group, and (iii) the B. cornuta group. B. worthingtoni and B. arietans are not included in any of these lineages. Eurasian viperines could be unambiguously devided into four monophyletic groups: (i) Pseudocerastes and Eristicophis, (ii) European vipers (Vipera s.str.), (iii) Middle East Macrovipera plus Montivipera (Vipera xanthina group), and (iv) North African Macrovipera plus Vipera palaestinae and Daboia russelii. These evolutionary lineages are consistent with historical biogeographical patterns. According to our analyses, the viperines originated in the Oligocene in Africa and successively underwent a first radiation leading to the five basal groups. The radiation might have been driven by the possession of an effective venom apparatus and a foraging startegy (sit-wait-strike) superior in most African biomes and might have been adaptive. The next diversifications led to the Proatheris-Atheris furcation, the basal Bitis splitting, and the emergence of the basal lineages within the Eurasian stock. Thereafter, lineages within Echis, Atheris, and Cerastes evolved. The emergence of three groups within Vipera s.l. might have been forced by the existence of three land masses during the early Miocene in the area of the Paratethys and the Mediterranean Seas. Taxonomic consequences of these findings are discussed. PMID:11286494

Lenk, P; Kalyabina, S; Wink, M; Joger, U

2001-04-01

64

The Morphology of Vipera ammodytes transcaucasiana (Reptilia, Viperidae) Specimens Collected from Murgul (Artvin, Turkey)  

Microsoft Academic Search

The morphological characteristics and distribution of Vipera ammodytes transcaucasiana, which is a member of the Vipera kaznakovi group, were studied. The transcaucasian horned viper specimens were captured from Murgul, Artvin, in Turkey. This species differs from all other vipers in the Near and Middle East in respect of its pronounced horn. It is similar to Vipera pontica in the greenish-yellowish

Bilal KUTRUP

65

The in vitro toxicity of venoms from South Asian Hump-nosed pit vipers (Viperidae: Hypnale)  

PubMed Central

Hump-nosed pit vipers (Genus Hypnale) are venomous snakes from South India and Sri Lanka. Envenoming by Hypnale species may cause significant morbidity and is characterized by local envenoming and less commonly coagulopathy and acute renal failure. Currently there are three nominal species of this genus: H. hypnale, H. zara and H. nepa. This study investigates the biochemical and pharmacological properties of the venoms from the three Hypnale species in Sri Lanka. The three Hypnale venoms had similar chromatographic profiles using reverse phase high performance liquid chromatography and fractions with procoagulant activity were identified. Hypnale venoms had potent cytotoxicity in cultured rat aorta smooth muscle cells with similar IC50 values. The venoms had weak neurotoxic and myotoxic activity in the isolated chick biventer muscle preparation. They had mild procoagulant activity with close MCC5 values and also phospholipase activity. Locally available polyvalent antivenom did not neutralise any venom effects. The study demonstrates that the three Hypnale venoms are similar and cytotoxicity appears to be the most potent effect, although they have mild procoagulant activity. These findings are consistent with clinical reports. PMID:21677795

Maduwage, Kalana; Hodgson, Wayne C; Konstantakopoulos, Nicki; O'Leary, Margaret A; Gawarammana, Indika; Isbister, Geoffrey K

2011-01-01

66

The in vitro toxicity of venoms from South Asian hump-nosed pit vipers (Viperidae: Hypnale).  

PubMed

Hump-nosed pit vipers (Genus Hypnale) are venomous snakes from South India and Sri Lanka. Envenoming by Hypnale species may cause significant morbidity and is characterized by local envenoming and less commonly coagulopathy and acute renal failure. Currently there are three nominal species of this genus: H. hypnale, H. zara and H. nepa. This study investigates the biochemical and pharmacological properties of the venoms from the three Hypnale species in Sri Lanka. The three Hypnale venoms had similar chromatographic profiles using reverse phase high performance liquid chromatography and fractions with procoagulant activity were identified. Hypnale venoms had potent cytotoxicity in cultured rat aorta smooth muscle cells with similar IC(50) values. The venoms had weak neurotoxic and myotoxic activity in the isolated chick biventer muscle preparation. They had mild procoagulant activity with close MCC(5) values and also phospholipase activity. Locally available polyvalent antivenom did not neutralise any venom effects. The study demonstrates that the three Hypnale venoms are similar and cytotoxicity appears to be the most potent effect, although they have mild procoagulant activity. These findings are consistent with clinical reports. PMID:21677795

Maduwage, Kalana; Hodgson, Wayne C; Konstantakopoulos, Nicki; O'Leary, Margaret A; Gawarammana, Indika; Isbister, Geoffrey K

2011-01-01

67

Within-clutch variation in venoms from hatchlings of Deinagkistrodon acutus (Viperidae).  

PubMed

We used 17 hatchling five-paced pit-vipers snakes (Deinagkistrodon acutus) to study within-clutch variation in snake venoms. We measured venom yield and total protein content, and examined the correlations between venom yield and hatchling size [snout-vent length (SVL) and body mass]. We also analyzed the electrophoretic profiles and enzymatic activities of venoms from hatchlings. Lyophilized venom mass was not correlated with SVL, nor with body mass. Liquid venom mass and total protein content were not correlated with body mass, but were positively correlated with SVL. Venom composition, as shown in SDS-PAGE chromatograms did vary among individuals but there were biochemical differences in activity which had to be due to subtle venom composition differences between the sexes. Female hatchlings showed higher esterolytic and fibrinogenolytic activities but lower proteolytic, collagenolytic, phosphomonoesterase and fibrinolytic activities than male hatchlings. We did not find sexual differences in 5' nucleotidase, phospholipase A(2) and hyaluronidase activities, and l-amino acid oxidase activities in either female or male hatchlings. Within-clutch variation in venoms from D. acutus hatchlings should be attributed to the individual-based differences in presence or absence, and the relative amount of the protein components, and might have a genetic basis. PMID:21459103

Gao, Jian-Fang; Qu, Yan-Fu; Zhang, Xiu-Qin; Ji, Xiang

2011-06-01

68

Unusual horizontal transfer of a long interspersed nuclear element between distant vertebrate classes  

PubMed Central

We have shown previously by Southern blot analysis that Bov-B long interspersed nuclear elements (LINEs) are present in different Viperidae snake species. To address the question as to whether Bov-B LINEs really have been transmitted horizontally between vertebrate classes, the analysis has been extended to a larger number of vertebrate, invertebrate, and plant species. In this paper, the evolutionary origin of Bov-B LINEs is shown unequivocally to be in Squamata. The previously proposed horizontal transfer of Bov-B LINEs in vertebrates has been confirmed by their discontinuous phylogenetic distribution in Squamata (Serpentes and two lizard infra-orders) as well as in Ruminantia, by the high level of nucleotide identity, and by their phylogenetic relationships. The horizontal transfer of Bov-B LINEs from Squamata to the ancestor of Ruminantia is evident from the genetic distances and discontinuous phylogenetic distribution. The ancestor of Colubroidea snakes is a possible donor of Bov-B LINEs to Ruminantia. The timing of horizontal transfer has been estimated from the distribution of Bov-B LINEs in Ruminantia and the fossil data of Ruminantia to be 40–50 My ago. The phylogenetic relationships of Bov-B LINEs from the various Squamata species agrees with that of the species phylogeny, suggesting that Bov-B LINEs have been maintained stably by vertical transmission since the origin of Squamata in the Mesozoic era. PMID:9724768

Kordis, Dusan; Gubensek, Franc

1998-01-01

69

NEW DISTRIBUTION RECORDS FOR THE QUERÉTERO DUSKY RATTLESNAKE CROTALUS AQUILUS (VIPERIDAE), WITH COMMENTS ON MORPHOLOGY AND HABITAT USE  

Microsoft Academic Search

We provide the 1st documented accounts of the Mexican endemic rattlesnake Crotalus aquilus from the state of México. The new records extend the known distribution of the species into a region where it may be sympatric with the superficially similar C. triseriatus. Because these taxa have previously been subject to some taxonomic confu- sion, we performed a preliminary morphological comparison

Jesse M. Meik; Estrella Mociño Deloya; Kirk Setser

2007-01-01

70

Evolution of reptilian viviparity: a test of the maternal manipulation hypothesis in a temperate snake, Gloydius brevicaudus (Viperidae).  

PubMed

We kept 48 gravid short-tailed pit vipers (Gloydius brevicaudus) under four laboratory thermal conditions during gestation and collected 10 females from the field soon before they gave birth to test whether Shine's (1995) maternal manipulation hypothesis applies to temperate reptiles. Females thermoregulated more precisely but did not shift their selected body temperatures during pregnancy, with females at high body temperatures giving birth early in the breeding season. The lowest (22 degrees C) and highest (32 degrees C) temperature treatments Increased maternal mortality and resulted in production of offspring with smaller body dimensions. More deformed offspring were produced at 32 degrees C, and more poorly performing offspring were produced at 22 degrees C. In the field, air temperatures lower than 22 degrees C and higher than 32 degrees C accounted for about 9% and 33% of total temperature readings, respectively. However, offspring produced by field-caught females did not differ from those produced by laboratory-kept females with body temperatures optimal for embryonic development in nearly all traits examined. This suggests that in nature, gravid females avoid exposure of their embryos to temperature extremes through thermoregulation. Our study validates the key prediction of the maternal manipulation hypothesis that maternal thermoregulation should enhance fitness-related offspring traits, and demonstrates that viviparity evolves in temperate reptiles because internal development shields offspring from temperature extremes. PMID:20192693

Gao, Jian-Fang; Qu, Yan-Fu; Luo, Lai-Gao; Ji, Xiang

2010-03-01

71

Comparative in-vivo toxicity of venoms from South Asian hump-nosed pit vipers (Viperidae: Crotalinae: Hypnale)  

PubMed Central

Background Envenoming by south Asian hump-nosed pit vipers (Genus: Hypnale) is a significant health issue in Sri Lanka and in peninsular India. Bites by these snakes frequently lead to local envenoming, coagulopathy and acute renal failure even resulting in death. Recently the genus was revised and the existence of three species viz H. hypnale, H. nepa and H. zara were recognized. There is, however, a paucity of information on the toxicity of the venoms of these species. Hence, we compared the toxic effects of the three Hypnale venoms using BALB/c mice. Findings Intraperitoneal median lethal doses (LD50) for H. hypnale, H. zara and H. nepa venoms were 1.6, 6.0 and 9.5??g protein/g respectively. Minimum haemorrhagic doses for venoms of H. hypnale, H. zara and H. nepa were 3.4, 11.0 and 16.6??g protein/mouse respectively. The minimum necrotic doses for the same venoms were 15.0, 55.1 and 68.2??g protein/mouse respectively. Severe congestion and petecheal haemorrhages were observed in lungs, kidneys, liver and the alimentary tract. Histopathogical examination of kidneys revealed proximal tubular cell injury and acute tubular necrosis with intact basement membrane indicating possible direct nephrotoxicity. Hypnale venoms caused pulmonary oedema, hepatocellular degeneration and necrosis, focal neuronal degeneration in brain and extramedullary haemopoiesis in spleen. H. hypnale venom caused all above histopathological alterations at lower doses compared to the other two. Conclusion Hypnale venoms cause similar pathological changes with marked differences in the severity of the toxic effects in vivo. Therefore, differences in the severity of the clinical manifestations could possibly be seen among bite victims of the three Hypnale species. PMID:22932058

2012-01-01

72

DISCOVERY OF THE MADAGASCAR SERPENT-EAGLE, EUTRIORCHIS ASTUR, IN CENTRAL AND SOUTHEASTERN MADAGASCAR. (U915543)  

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

73

Complete mitochondrial genome sequence from an endangered Indian snake, Python molurus molurus (Serpentes, Pythonidae).  

PubMed

This paper reports the complete mitochondrial genome sequence of an endangered Indian snake, Python molurus molurus (Indian Rock Python). A typical snake mitochondrial (mt) genome of 17258 bp length comprising of 37 genes including the 13 protein coding genes, 22 tRNA genes, and 2 ribosomal RNA genes along with duplicate control regions is described herein. The P. molurus molurus mt. genome is relatively similar to other snake mt. genomes with respect to gene arrangement, composition, tRNA structures and skews of AT/GC bases. The nucleotide composition of the genome shows that there are more A-C % than T-G% on the positive strand as revealed by positive AT and CG skews. Comparison of individual protein coding genes, with other snake genomes suggests that ATP8 and NADH3 genes have high divergence rates. Codon usage analysis reveals a preference of NNC codons over NNG codons in the mt. genome of P. molurus. Also, the synonymous and non-synonymous substitution rates (ka/ks) suggest that most of the protein coding genes are under purifying selection pressure. The phylogenetic analyses involving the concatenated 13 protein coding genes of P. molurus molurus conformed to the previously established snake phylogeny. PMID:22331485

Dubey, Bhawna; Meganathan, P R; Haque, Ikramul

2012-07-01

74

Morphological variation and affinities of the poorly known snake Atractus caxiuana (Serpentes: Dipsadidae) .  

PubMed

Atractus caxiuana was recently described based on three specimens (two males and one female) from the Floresta Nacional de Caxiuanã, municipality of Melgaço, state of Pará, in the eastern portion of the Brazilian Amazon. Apart from the type series, no additional samples are known for the species. In this study, we report new specimens of A. caxiuana, providing new morphological data (meristic, morphometric, pholidosis, colour pattern, and hemipenis) and localities. We relate the variability displayed by the characters analyzed to sexual dimorphism, geographic variation, and ontogeny. Additionally, we provide detailed comparisons with A. collaris and putative sister species, and propose a new species group to accommodate this distinct and possible monophyletic assemblage.  PMID:25113336

Passos, Paulo; Ramos, Luciana O; Pinna, Pedro H; Prudente, Ana L C

2013-01-01

75

Unusual labial glands in snakes of the genus Geophis Wagler, 1830 (Serpentes: Dipsadinae).  

PubMed

Geophis belongs to the goo-eating dipsadine assemblage of snakes that are known to feed exclusively on earthworms, snails, and slugs. Although the unusual feeding strategies of the goo-eating dipsadines are well known (but poorly documented), little attention has been paid to their internal anatomy. Here, we describe a new and noteworthy morphological and histochemical condition of the infralabial glands in three species of Geophis (G. brachycephalus, G. nasalis and G. semidoliatus), all earthworm feeders. Their infralabial glands are constituted of two distinct parts: an anterolateral portion composed of mucous and seromucous cells that stretches from the tip of the dentary to the corner of the mouth, and a tubular posteromedial portion that is exclusively seromucous. The anterolateral portion receives fibers of the levator anguli oris muscle that attaches on its posterodorsal extremity while the posteromedial portion extends posteriorly to the corner of the mouth where it receives fibers of the adductor mandibulae externus medialis muscle. Furthermore, the posteromedial portion of the infralabial gland is constituted by large acini filled with secretion that is periodic acid-Schiff positive. These acini release their secretion directly into a large lumen located in the middle of the glandular portion. In the three species examined, the supralabial glands show a traditional configuration, being constituted of mucous and seromucous cells and retaining an enlarged part in its caudal region that resembles a Duvernoy's gland. The presence in Geophis of an expanded lumen in part of the infralabial gland that is compressed by an adjacent muscle suggests a more specialized role for the secretion produced by these glands that may not be related to envenomation but rather to prey transport and mucus control. PMID:24127255

de Oliveira, Leonardo; da Costa Prudente, Ana Lúcia; Zaher, Hussam

2014-01-01

76

Complete mitochondrial genome of the black-headed snake Sibynophis collaris (Squamata, Serpentes, Colubridae).  

PubMed

The black-headed snake Sibynophis collaris (Reptilia, Squamata, Colubridae) is a least concern species in the world. Two universal and two specific polymerase chain reaction (PCR) primers were used for long PCRs to amplify the whole mitochondrial genome of S. collaris. The products were subjected to do sequencing reactions. The complete genome is 17,163 bp in size, containing 37 genes coding for 13 proteins, 2 rRNAs, 22 tRNAs, and 2 control regions (CRI and CRII). The results could play an important role in the preservation of genetic resources for helping conservation of the endangered species. PMID:22040070

Jang, Kuem Hee; Hwang, Ui Wook

2011-08-01

77

Envenomation by neotropical opisthoglyphous colubrid Thamnodynastes cf. pallidus Linne, 1758 (Serpentes:Colubridae) in Venezuela.  

PubMed

This is a case report of a "non-venomous" snake bite in a herpetologist observed at the Sciences Faculty of the Universidad de los Andes (Mérida, Venezuela). The patient was bitten on the middle finger of the left hand, and shows signs of pronounced local manifestations of envenomation such as bleeding from the tooth imprint, swelling and warmth. He was treated with local care, analgesics, and steroids. He was dismissed from the hospital and observed at home during five days with marked improvement of envenomation. The snake was brought to the medical consult and identified as a Thamnodynastes cf. pallidus specimen. This report represents the first T. pallidus accident described in a human. PMID:15517037

Diaz, Fresnel; Navarrete, Luis F; Pefaur, Jaime; Rodriguez-Acosta, Alexis

2004-01-01

78

Helminthic parasites of water snakes, Natrix spp. (Serpentes: Colubridae), from southeast Texas  

E-print Network

is the distance from mid-acetabulum to the anterior 'extremity. Two DeMann's formulas are used in nematode descriptions, the ratio to total length of 1) the distance of the vulva from the anterior extremity and 2) the length of the esophagus. Wright and Wright... is the distance from mid-acetabulum to the anterior 'extremity. Two DeMann's formulas are used in nematode descriptions, the ratio to total length of 1) the distance of the vulva from the anterior extremity and 2) the length of the esophagus. Wright and Wright...

Guidry, Edmund Vaughn

2012-06-07

79

Serpents in the Garden: English Professors in Contemporary Film and Television  

ERIC Educational Resources Information Center

In an article on "Smart People" (2008), a film in which Dennis Quaid plays an English professor who becomes romantically involved with a former student, Jeffery J. Williams notes that a "common complaint among academics is that films don't depict them correctly, and in some ways Quaid was accoutered by central casting, beginning the movie in a…

Carens, Timothy L.

2010-01-01

80

Kleptothermy: an additional category of thermoregulation, and a possible example in sea kraits (Laticauda laticaudata, Serpentes)  

PubMed Central

Lacking the capacity for thermogenesis, most ectotherms inhabiting thermally heterogeneous environments rely instead upon exploiting that ambient heterogeneity. In many cases they maintain body temperatures within a narrow range despite massive spatial and temporal variation in ambient conditions. Reliance on diverse thermal opportunities is reflected in specific terms for organisms that bask in sunlight to regulate their temperature (heliotherms), or that press their bodies against warm substrates to facilitate heat flow (thigmotherms), or that rely on large body mass to maintain thermal constancy (gigantothermy). We propose an additional category of thermoregulators: kleptotherms, which regulate their own temperature by ‘stealing’ heat from other organisms. This concept involves two major conditions: the thermal heterogeneity created by the presence of a warm organism in a cool environment and the selective use of that heterogeneity by another animal to maintain body temperatures at higher (and more stable) levels than would be possible elsewhere in the local area. Kleptothermy occurs in endotherms also, but is usually reciprocal (rather than unilateral as in ectotherms). Thermal monitoring on a small tropical island documents a possible example of kleptothermy, based on high stable temperatures of a sea snake (Laticauda laticaudata) inside a burrow occupied by seabirds. PMID:19656862

Brischoux, Francois; Bonnet, Xavier; Shine, Richard

2009-01-01

81

Neogene diversification and taxonomic stability in the snake tribe Lampropeltini (Serpentes: Colubridae)  

Microsoft Academic Search

The impact of climate change during the Pleistocene on organ- isms living in temperate areas of the world has been documented for more than fifty years (Rand, 1948). A major impact of Pleisto- cene glacial cycles on vertebrates in temperate zones is hypothe- sized to be the isolation of species into allopatric populations (Avise and Walker, 1998). Refugial isolation and

R. Alexander Pyron; Frank T. Burbrink

2009-01-01

82

Evolutionary derived modulations of attention to two common fear stimuli: Serpents and hostile humans  

Microsoft Academic Search

In this paper we present an evolutionary analysis of attention to stimuli that are threatening from an evolutionary perspective, such as angry faces and snakes. We review data showing that angry, photographically depicted angry faces are more rapidly detected than happy faces in a visual search setting provided that they are male and that distractors are redundant in the sense

Arne Öhman; Sandra C. Soares; Pernilla Juth; Björn Lindström; Francisco Esteves

2012-01-01

83

The Rod and the Serpent: History’s Ultimate Healing Symbol  

Microsoft Academic Search

The snake has served as a medical emblem for more than 2400 years, since its association with the ancient Greek god of medicine\\u000a and healing, Asclepius, in the 4th century BC. Its symbolic background can be traced further back to the worship of gods of\\u000a earth’s blossom in ancient Egypt and earth-related deities of the archaic period of Greek antiquity. It

Stavros A. Antoniou; George A. Antoniou; Robert Learney; Frank A. Granderath; Athanasios I. Antoniou

2011-01-01

84

The transvestite serpent: why do male garter snakes court (some) other males?  

PubMed

In large mating aggregations of red-sided garter snakes, Thamnophis sirtalis parietalis, in Manitoba, male courtship is directed not only to females, but also to other males with female-like skin lipids ('she-males'). We show that 'she-maleness' is an intrinsic property of a male rather than an artefact of lipid transfer from females, and that male-male courtship is very common in the field. She-males were distinctive in terms of appearance (they were heavier than other males and more often covered with mud), behaviour (they were inactive and rarely courted females) and performance (they were slow crawlers, ineffective courters and easily outcompeted by other males in mating trials). 'She-maleness' was not a characteristic of a particular subset of males, as envisaged in previous work; instead, it was a transitory phase that most (perhaps all) male snakes passed through soon after they first emerged from the winter den. Recently emerged males spent their first day or two relatively inactive, while restoring physiological functions (including locomotor performance and courtship ability). Experimental application of female skin lipids on to males dramatically decreased courtship levels of the recipient snakes. Thus, recently emerged males may derive two kinds of benefit from mimicking female skin lipids. First, female mimicry 'switches off' the male's own (energetically expensive) courtship at a time when that courtship would be unproductive. Second, it may disadvantage his rivals by distracting them from females, and increasing their energy expenditure. Copyright 2000 The Association for the Study of Animal Behaviour. PMID:10675257

Shine; Harlow; LeMaster; Moore; Mason

2000-02-01

85

Mechanical properties of the integument of the common gartersnake, Thamnophis sirtalis (Serpentes: Colubridae)  

Microsoft Academic Search

The evolution of the ophidian feeding mechanism has involved substantial morphological restructuring associated with the ability to ingest relatively large prey. Previous studies examining the morphological consequences of macrophagy have concentrated on modifications of the skull and cephalic musculature. Although it is evident that macrophagy requires highly compliant skin, the mechanical properties of the ophidian integument have received limited attention,

Gabriel Rivera; Alan H. Savitzky; Jeffrey A. Hinkley

2005-01-01

86

Mechanical properties of the integument of the common gartersnake, Thamnophis sirtalis (Serpentes: Colubridae).  

PubMed

The evolution of the ophidian feeding mechanism has involved substantial morphological restructuring associated with the ability to ingest relatively large prey. Previous studies examining the morphological consequences of macrophagy have concentrated on modifications of the skull and cephalic musculature. Although it is evident that macrophagy requires highly compliant skin, the mechanical properties of the ophidian integument have received limited attention, particularly in the context of feeding. We examined mechanical properties of skin along the body axis in Thamnophis sirtalis (Colubridae). Data were collected from tensile tests and were analyzed using a multivariate analysis of variance (MANOVA) and post-hoc multiple comparison tests. Significant differences in mechanical properties were detected among regions of the body. In general, prepyloric skin is more compliant than postpyloric skin, consistent with the demands of macrophagy. PMID:16043596

Rivera, Gabriel; Savitzky, Alan H; Hinkley, Jeffrey A

2005-08-01

87

Morphological systematics of kingsnakes, Lampropeltis getula complex (Serpentes: Colubridae), in the eastern United States  

Microsoft Academic Search

Kingsnakes of the Lampropeltis getula complex range throughout much of North America. Using morphology and color pattern, Blaney made the last revision of this species complex nearly 30 years ago and recognized seven subspecies. Furthermore, Blaney hypothesized that populations in the eastern United States consist of two closely related taxa, L. g. getula & L. g. floridana, whichare morphologically divergent

KENNETH L. KRYSKO; WALTER S. JUDD

2006-01-01

88

“Three serpents with tongues and eyes of flame”: the 1905 pogroms in Russian?Jewish literature  

Microsoft Academic Search

Despite the fact that the 1881\\/82 pogroms had a much greater effect on Jewish thinking, representing a watershed in the Jewish strategy of assimilation, the 1905 pogroms were much more widely mirrored in literature. The Silver Age period of Russian literature had a great impact on new stylistic strategies that were capable of depicting the horror and avoiding the sentimental,

Zsuzsa Hetényi

2010-01-01

89

Mitochondrial DNA-Based phylogeography of North American rubber boas, Charina bottae (Serpentes: Boidae).  

PubMed

We used 783 bp of mitochondrial DNA sequences to study the phylogeography of Charina bottae (rubber boa) in western North America, with an emphasis on populations from California (U.S.A.). Maximum-parsimony and maximum-likelihood methods identified a basal divergence within C. bottae that corresponds to southern and northern segments of its current distribution. These clades coincide with the ranges of the two recognized subspecies, C. b. umbratica in the south and C. b. bottae to the north. A subsequent cladogenetic event in the C. b. bottae clade resulted in two groupings, which we refer to as the Sierra Nevada and the Northwestern subclades, based on the geographic distribution of their constituent populations. The two subclades have completely allopatric distributions, with a genetic break in the vicinity of Lassen Volcanic National Park in northeastern California, an area that was subjected to glaciation during the Pleistocene and that has been volcanically active in the past 100 years. An earlier genetic study documented fixed differences between populations of bottae and umbratica in four of seven allozymes surveyed, and despite noticeable variation and overlap in the characters that define C. b. bottae and C. b. umbratica, the two forms still can be separated in most cases using a suite of morphological traits. All available evidence thus indicates that C. b. umbratica is a genetically cohesive, allopatric taxon that is morphologically diagnosable, and we conclude that it is an independent evolutionary unit that should be recognized as a distinct species, Charina umbratica. PMID:11161758

Rodríguez-Robles, J A; Stewart, G R; Papenfuss, T J

2001-02-01

90

Mitochondrial DNA-Based Phylogeography of North American Rubber Boas, Charina bottae (Serpentes: Boidae)  

Microsoft Academic Search

We used 783 bp of mitochondrial DNA sequences to study the phylogeography of Charina bottae (rubber boa) in western North America, with an emphasis on populations from California (U.S.A.). Maximum-parsimony and maximum-likelihood methods identified a basal divergence within C. bottae that corresponds to southern and northern segments of its current distribution. These clades coincide with the ranges of the two

Javier A Rodr??guez-Robles; Glenn R. Stewart; Theodore J. Papenfuss

2001-01-01

91

Nest sites of a northern population of an oviparous snake, Opheodrys vernalis (Serpentes, Colubridae)  

Microsoft Academic Search

The thermal characteristics of nest sites of the oviparous snake, Opheodrys vernalis, were studied in 1975 and 1976 near Cheboygan, Michigan. These characteristics were contrasted to the thermal regime of potential nest sites at shallow (1 cm) and deep (30 cm) locations in two contrasting habitats, open fields versus forest. On the basis of the great difference in temperatures of

Owen J. Sexton; Lee Claypool

1978-01-01

92

Coccidian parasites (Apicomplexa: Eimeriidae) of the endemic Florida snake Tantilla relicta Telford (Serpentes: Colubridae)  

Microsoft Academic Search

The endemic Florida snake Tantilla relicta Telford is parasitised by six species of coccidia. Caryospora tantillae n. sp. has nearly spherical oöcysts, 19.6 × 18.9 µm (16–22 × 16–21), with no polar body, and an oöcyst length\\/width ratio (shape index, SI) of 1.04 (1.00–1.11). Ovoidal sporocysts are 15.1 × 11.6 µm (12–17 × 10–13), with an SI of 1.30 (1.1–1.6),

Sam R. Telford Jr

1997-01-01

93

Ultrastructure and wear patterns of the ventral epidermis of four snake species (Squamata, Serpentes).  

PubMed

Snakes are limbless tetrapods highly specialized for sliding locomotion. This locomotion leads to the skin being exposed to friction loads, especially on the ventral body side, which leads to wear. It is presumed that snakes therefore have specific optimizations for minimizing abrasion. Scales from snakes with habitat, locomotor and/or behavior specializations have specific gradients in material properties that may be due to different epidermal architecture. To approach this issue we examined the skin of Lampropeltis getula californiae (terrestrial), Epicrates cenchria cenchria (generalist), Morelia viridis (arboreal), and Gongylophis colubrinus (burrowing) with a focus on (i) the ultrastructure of the ventral epidermis and (ii) the qualitative abrasion pattern of the ventral scales. Scanning and transmission electron microscopy revealed variations in the structure, thickness, layering, and material composition of the epidermis between the species. Furthermore, SEM and white light interferometer images of the scale surface showed that the abrasion patterns differed, even when the snakes were reared on the same substrate. These data support the idea that (i) a specific gradient in material properties may be due to a variation in epidermis architecture (thickness/ultrastructure) and (ii) this variation may be an optimization of material properties for specific ways of life. PMID:25169958

Klein, Marie-Christin G; Gorb, Stanislav N

2014-10-01

94

Morphological variation and taxonomy of Atractus latifrons (Günther, 1868) (Serpentes: Dipsadidae).  

PubMed

As currently understood Atractus latifrons is widely distributed in South America, occurring from Suriname to the east of the Andes in Bolivia. Throughout this widespread distribution, at least three distinct color patterns were previously reported in the literature. Here, we test whether quantitative variation and qualitative distribution of morphological characters are correlated with any color pattern displayed by the species along its range. We recognize three aposematic color patterns (bicolor in monads, tricolor in dyads, and tricolor in tetrads) for A. latifrons. We found no obvious correspondence between these patterns and any character systems analyzed herein. Additionally, we redescribe the holotype of A. latifrons and report on morphological variability (meristics, morphometrics, color patterns, and hemipenis) and geographical distribution (extending its distribution to the state Roraima, Brazil) of the species.  PMID:25283190

Almeida, Paula C; Feitosa, Darlan T; Passos, Paulo; Prudente, Ana L C

2014-01-01

95

Close karyological kinship between the reptilian suborder serpentes and the class aves  

Microsoft Academic Search

In contrast to the situation found in two classes of warm-blooded vertebrates, mammals and birds, the class Reptilia is not uniform with regard to total genetic content; rather, it contains two distinct categories. The close cytological kinship between snakes and birds was revealed. Both are almost identical in total genetic content, which is about 50 per cent that of placental

Willy Beçak; Maria Luiza Beçak; H. R. S. Nazareth; Susumu Ohno

1964-01-01

96

When colour patterns reflect phylogeography: new species of Dasypeltis (Serpentes: Colubridae: Boigini) from West Africa.  

PubMed

Six colour phases are currently known in the genus Dasypeltis in West Africa, three in the D. scabra complex and three in the D. fasciata complex. Molecular phylogenetic analysis reveals that all correspond to distinct species. D. parascabra sp. nov. is described from wet savannah areas of Guinea and Ivory Coast. D. latericia is given full specific rank. The validity of D. sahelensis, D. gansi and D. confusa - three species recently described on the basis of colour pattern and biogeography - is confirmed. D. fasciata is confined to rain forest areas of West and Central Africa. D. scabra is absent from West Africa. PMID:22847016

Trape, Sébastien; Mediannikov, Oleg; Trape, Jean-François

2012-07-01

97

The Serpent in the Garden State: Juvenile Delinquency in 1920s New Jersey  

ERIC Educational Resources Information Center

School administrators, educators, psychologists, social workers, the juvenile courts, institutional reformers, and others shape the manner in which children are labeled, portrayed, and treated. However, the agendas, motivations, political language, and influence of these "helping professionals" in "treating" and "reforming" juvenile delinquents…

Ferry, Thomas M.

2010-01-01

98

Food resources influence spatial ecology, habitat selection, and foraging behavior in an ambush-hunting snake (Viperidae: Bothrops asper): an experimental study.  

PubMed

Prey availability affects many aspects of predators' life history and is considered a primary factor influencing individuals' decisions regarding spatial ecology and behavior, but few experimental data are currently available. Snakes may represent ideal model organisms relative to other animal groups for addressing such resource dependency, due to a presumably more direct link between food resources and many aspects of behavior and natural history. We experimentally investigated the relationship between food intake and spatial behavior in a population of the snake Bothrops asper in a Costa Rican lowland rainforest. Six adult snakes were allowed to forage naturally while six were offered supplemental food in the field, with both groups monitored using radiotelemetry. Mean home range size did not differ between groups presumably due to small sample size, but supplementally fed snakes demonstrated altered patterns of macro- and microhabitat selection, shorter and less frequent movements, and increased mass acquisition. Fed snakes also devoted less time to foraging efforts, instead more frequently remaining inactive and utilizing shelter. Because snakes were always fed in situ and not at designated feeding stations, observed shifts in habitat selection are not explained by animals simply moving to areas of higher food availability. Rather, B. asper may have moved to swamps in order to feed on amphibians when necessary, but remained in preferred forest habitat when food was otherwise abundant. The strong behavioral and spatiotemporal responses of snakes in this population may have been influenced by an overall scarcity of mammalian prey during the study period. PMID:22440190

Wasko, Dennis K; Sasa, Mahmood

2012-06-01

99

On the systematics of Trimeresurus labialis Fitzinger in Steindachner, 1867, a pitviper from the Nicobar Islands (India), with revalidation of Trimeresurus mutabilis Stoliczka, 1870 (Squamata, Viperidae, Crotalinae).  

PubMed

The Asian pitviper currently identified as Trimeresurus labialis Fitzinger in Steindachner, 1867 is revised on the basis of morphological data obtained from 37 preserved specimens originating from seven islands of the Nicobar Islands. Multivariate analyses shows that these specimens can be divided into two clusters of populations which differ by a series of constant taxonomically informative morphological characters. The first cluster, which includes the name-bearing types of Trimeresurus labialis Fitzinger in Steindachner, 1867, is present only on Car Nicobar Island. The second cluster, which includes the name-bearing types of Trimeresurus mutabilis Stoliczka, 1870, is distributed on the Central Nicobar Islands. We regard these clusters as distinct species, which are morphologically diagnosable and isolated from each other. As a consequence, Trimeresurus mutabilis, long considered a synonym of T. labialis, is here resurrected to specific level. A lectotype is designated for Trimeresurus mutabilis. PMID:24869554

Vogel, Gernot; David, Patrick; Chandramouli, S R

2014-01-01

100

Comparative study of anticoagulant and procoagulant properties of 28 snake venoms from families Elapidae, Viperidae, and purified Russell's viper venom-factor X activator (RVV-X).  

PubMed

Snake venoms consist of numerous molecules with diverse biological functions used for capturing prey. Each component of venom has a specific target, and alters the biological function of its target. Once these molecules are identified, characterized, and cloned; they could have medical applications. The activated clotting time (ACT) and clot rate were used for screening procoagulant and anticoagulant properties of 28 snake venoms. Crude venoms from Daboia russellii siamensis, Bothrops asper, Bothrops moojeni, and one Crotalus oreganus helleri from Wrightwood, CA, had procoagulant activity. These venoms induced a significant shortening of the ACT and showed a significant increase in the clot rate when compared to the negative control. Factor X activator activity was also measured in 28 venoms, and D. r. siamensis venom was 5-6 times higher than those of B. asper, B. moojeni, and C. o. helleri from Wrightwood County. Russell's viper venom-factor X activator (RVV-X) was purified from D. r. siamensis venom, and then procoagulant activity was evaluated by the ACT and clot rate. Other venoms, Crotalus atrox and two Naja pallida, had anticoagulant activity. A significant increase in the ACT and a significant decrease in the clot rate were observed after the addition of these venoms; therefore, the venoms were considered to have anticoagulant activity. Venoms from the same species did not always have the same ACT and clot rate profiles, but the profiles were an excellent way to identify procoagulant and anticoagulant activities in snake venoms. PMID:20685219

Suntravat, Montamas; Nuchprayoon, Issarang; Pérez, John C

2010-06-01

101

Comparative study of anticoagulant and procoagulant properties of 28 snake venoms from families Elapidae, Viperidae, and purified Russell's viper venom-factor X activator (RVV-X).  

PubMed

Snake venoms consist of numerous molecules with diverse biological functions used for capturing prey. Each component of venom has a specific target, and alters the biological function of its target. Once these molecules are identified, characterized, and cloned; they could have medical applications. The activated clotting time (ACT) and clot rate were used for screening procoagulant and anticoagulant properties of 28 snake venoms. Crude venoms from Daboia russellii siamensis, Bothrops asper, Bothrops moojeni, and one Crotalus oreganus helleri from Wrightwood, CA, had procoagulant activity. These venoms induced a significant shortening of the ACT and showed a significant increase in the clot rate when compared to the negative control. Factor X activator activity was also measured in 28 venoms, and D. r. siamensis venom was 5-6 times higher than those of B. asper, B. moojeni, and C. o. helleri from Wrightwood County. Russell's viper venom-factor X activator (RVV-X) was purified from D. r. siamensis venom, and then procoagulant activity was evaluated by the ACT and clot rate. Other venoms, Crotalus atrox and two Naja pallida, had anticoagulant activity. A significant increase in the ACT and a significant decrease in the clot rate were observed after the addition of these venoms; therefore, the venoms were considered to have anticoagulant activity. Venoms from the same species did not always have the same ACT and clot rate profiles, but the profiles were an excellent way to identify procoagulant and anticoagulant activities in snake venoms. PMID:20677373

Suntravat, Montamas; Nuchprayoon, Issarang; Pérez, John C

2010-09-15

102

Evolution of rattlesnakes (Viperidae; Crotalus) in the warm deserts of western North America shaped by Neogene vicariance and Quaternary climate change.  

PubMed

During Pleistocene, the Laurentide ice sheet rearranged and diversified biotic distributions in eastern North America, yet had minimal physical impact in western North America where lineage diversification is instead hypothesized to result from climatic changes. If Pleistocene climatic fluctuations impacted desert species, the latter would reflect patterns of restricted gene flow concomitant with indications of demographic bottlenecks. Accordingly, molecular evidence for refugia should be present within these distributions and for subsequent range expansions as conditions improved. We sought answers to these questions by evaluating mitochondrial DNA (mtDNA) sequences from four species of rattlesnakes [Crotalus mitchellii (speckled rattlesnake), Crotalus cerastes (sidewinder), Crotalus tigris (tiger rattlesnake), Crotalus ruber (red diamond rattlesnake)] with distributions restricted to desert regions of southwestern North America. We inferred relationships using parsimony and maximum likelihood, tested intraspecific clades for population expansions, applied an isolation-with-migration model to determine bi-directional migration rates (m) among regions, and inferred divergence times for species and clades by applying a semiparametric penalized likelihood approach to our molecular data. Evidence for significant range expansion was present in two of eight regions in two species (Crotalus mitchellii pyrrhus, C. tigris region north). Two species (C. cerastes, C. mitchellii) showed a distribution concomitant with northward displacement of Baja California from mainland México, followed by vicariant separation into subclades. Effects of Pleistocene climate fluctuations were found in the distributions of all four species. Three regional diversification patterns were identified: (i) shallow genetic diversity that resulted from Pleistocene climatic events (C. tigris, C. ruber); (ii) deep Pleistocene divisions indicating allopatric segregation of subclades within refugia (C. mitchellii, C. cerastes); and (iii) lineage diversifications that extended to Pliocene or Late Miocene (C. mitchellii, C. cerastes). Clade-diversifying and clade-constraining effects impacted the four species of rattlesnakes unequally. We found relatively high levels of molecular diversification in the two most broadly distributed species (C. mitchellii, C. cerastes), and lower levels of genetic diversification in the two species (C. tigris, C. ruber) whose ranges are relatively more restricted. Furthermore, in several cases, the distributions of subspecies were not congruent with our molecular information. We suggest regional conservation perspectives for southwestern deserts cannot rely upon subspecies as biodiversity surrogates, but must instead employ a molecular and deep historical perspective as a primary mechanism to frame biodiversity reserves within this region. PMID:16968275

Douglas, Michael E; Douglas, Marlis R; Schuett, Gordon W; Porras, Louis W

2006-10-01

103

NOTES ON SCUTELLATION, LENGTH, AND DISTRIBUTION OF RATTLESNAKES (SERPENTES: VIPERIDADE: CROTALUS) IN THE STATE OF HIDALGO, MEXICO  

Microsoft Academic Search

We studied the eight species of Crotalus inhabiting the Mexican state of Hidalgo and found additional variation involving number of scales, body length, and distribution previously unreported in the literature. Supplementary morphological variation is reported for C. aquilus and C. atrox, and new distributional records are reported for C. aquilus, C. atrox, C. intermedius, C. scutulatus, and C. totonacus.

Ángel Alberto VALENCIA-HERNÁNDEZ; Irene GOYENECHEA; Jesús Martín CASTILLO-CERÓN

104

'Heaven' for serpents? A mark-recapture study of tiger snakes (Notechis scutatus) on Carnac Island, Western Australia  

Microsoft Academic Search

Animals resident on small islands provide excellent opportunities to carry out detailed mark- recapture studies. Populations are closed and ecosystems are often simpler than those of mainland sites. These factors enable the study of cryptic species that have otherwise been neglected. Snakes are notable for their secretive nature and, as a result, few natural populations have been accurately described through

Xavier Bonnet; David Pearson; Mitchell Ladyman; Olivier Lourdais; Don Bradshaw

2002-01-01

105

The unexpected discovery of blind snakes (Serpentes: Typhlopidae) in Micronesia: Two new species of Ramphotyphlops from the Caroline Islands  

USGS Publications Warehouse

Two new blind snakes in the genus Ramphotyphlops are described from Ulithi (R. hatmaliyeb sp. nov.) and Ant Atoll (R. adocetus sp. nov.) in the Caroline Islands, the first blind snake species known from Micronesia east of Palau (excluding Ramphotyphlops braminus). Both species are unusual in being known only from small, low-lying atolls. They can be distinguished from other Ramphotyphlops by the combination of 22 scale rows over the length of the body; a wedge-shaped snout, without a keratinized keel; and a broad, pyriform (R. adocetus) or ovate (R. hatmaliyeb) rostral scale.

Wynn, A.H.; Reynolds, R.P.; Buden, D.W.; Falanruw, M.; Lynch, B.

2012-01-01

106

The unexpected discovery of blind snakes (Serpentes: Typhlopidae) in Micronesia: two new species of Ramphotyphlops from the Caroline Islands  

USGS Publications Warehouse

Two new blind snakes in the genus Ramphotyphlops are described from Ulithi (R. hatmaliyeb sp. nov.) and Ant Atoll (R. adocetus sp. nov.) in the Caroline Islands, the first blind snake species known from Micronesia east of Palau (excluding Ramphotyphlops braminus). Both species are unusual in being known only from small, low-lying atolls. They can be distinguished from other Ramphotyphlops by the combination of 22 scale rows over the length of the body; a wedge-shaped snout, without a keratinized keel; and a broad, pyriform (R. adocetus) or ovate (R. hatmaliyeb) rostral scale.

Wynn, Addison H.; Reynolds, Robert P.; Buden, Donald W.; Falanruw, Marjorie; Lynch, Brian

2012-01-01

107

["Lingue di seripi", "serpents' tongues" and "glossopetrae". Highlights from the history of popular "cult" medicine in early modern times].  

PubMed

In the 16th, 17th and 18th century "Glossopetrae", popularly known as "Lingue di Serpi", found on the Mediterranean island of Malta, were extensively used for medical purposes as antidotes. These fossil teeth, including specimens of the "Carcharodon Megalodon" (an extinct variant of the great white shark), were ground to powder or used as amulet pendants and "credence" and exported to pharmacies and shops in various cities of Europe. In antiquity, authors like Plinius or Solinus, excluding any religious connotations, had regarded "Glossopetrae" as objects "fallen from heaven on dark moonless nights". However, from the beginning of the 16th century the miraculous antidotic power of the specimens found at Malta was very strongly connected with the Pauline cult there. This cult owed ist origin to the excerpt of the shipwreck of the Apostle of the Gentiles on this island, as recorded in the New Testament. As in so many cases found in medieval and early modern medicine and pharmacy, the renown, collection, distribution and use of the antidote "Glossopetrae" or "Lingue di Serpi" was never limited to its real chemical and pharmaceutical properties. In the period of enlightenment and secular thinking mythic medicine as "Glossopetrae" had lost ist "magical" power. Consequently, with beginning of the late 18th century also the Maltese "Glossopetrae" featured in literature merely as exotic objects of curiosity or symbols of an age bound to medical superstition. PMID:9333999

Freller, T

1997-01-01

108

A NEW SPECIES OF HEPATOZOON (APICOMPLEXA: ADELEORINA) FROM PYTHON REGIUS (SERPENTES: PYTHONIDAE) AND ITS EXPERIMENTAL TRANSMISSION BY A MOSQUITO VECTOR  

Microsoft Academic Search

Hepatozoon ayorgbor n. sp. is described from specimens of Python regius imported from Ghana. Gametocytes were found in the peripheral blood of 43 of 55 snakes examined. Localization of gametocytes was mainly inside the erythrocytes; free gametocytes were found in 15 (34.9%) positive specimens. Infections of laboratory-reared Culex quinquefasciatus feeding on infected snakes, as well as experimental infection of juvenile

Michal Sloboda; Martin Kamler; Jana Bulantová; Jan Votýpka; David Modrý

2007-01-01

109

Lessons Learned from Cosmic Serpent, a professional development project for informal educators on science and native ways of knowing  

NASA Astrophysics Data System (ADS)

How can one engage native communities and the public alike in understanding nature and our universe? Our approach has been to bring together practitioners at informal science centers, cultural museums, and tribal museums to develop relationships cross culturally, learn about different ways of studying and learning about nature and our universe, and start to develop informal education programs or exhibits at their institution through their new understandings and peer networks. The design of the grant has been to provide an initial week-long professional development workshop in a region in the Western U.S. with a follow-up workshop in that region the following year, culminating in a final conference for all participants. We focus on three regions: the southwest (SW - Utah, Arizona, New Mexico and Colorado); the northwest (Alaska, Washington, and Oregon); and California. We are in our fourth year of our four year grant and have in this time organized and run three regional week-long workshops and two follow-up workshops (in the SW and NW). We have learned many lessons through this work, including: the importance of incorporating workshop participants as presenters in the workshop agenda; how the content of astronomy, earth science, ecology, and health resonates with these museum professionals and can easily be discussed with different world views in this type of cross cultural science education; and how to best present different ways of knowing how nature and our universe work (science) in a manner that provides a context for science educators and museum professionals. In our poster presentation, we will share these and other lessons we have learned from the leadership perspective of bringing together such a diverse and under-represented-in-science group of educators.

Peticolas, L. M.; Maryboy, N.; Begay, D.; Paglierani, R.

2010-12-01

110

Lessons Learned from Cosmic Serpent: A Professional Development Project for Informal Educators on Science and Native Ways of Knowing  

NASA Astrophysics Data System (ADS)

How can one engage native communities and the public alike in understanding nature and our universe? Our approach has been to bring together practitioners at informal science centers, cultural museums, and tribal museums to develop relationships cross-culturally, to learn about different ways of studying and learning about nature and our universe, and to start to develop informal education programs or exhibits at their institution through their new understandings and peer networks. The design of this National Science Foundation (NSF) grant has been to provide an initial week-long professional development workshop in a region in the Western U.S. with a follow-up workshop in that region the following year, culminating in a final conference for all participants. We focus on three regions: the southwest (Utah, Arizona, New Mexico, and Colorado), the northwest (Alaska, Washington, and Oregon); and California. We are in our third year of our four-year grant and have in this time organized and run three regional week-long workshops and a follow-up workshop in the southwest. We have learned many lessons through this work, including: the importance of incorporating workshop participants as presenters in the workshop agenda; how the content of astronomy, ecology, and health resonates with these museum professionals and can easily be discussed with different world views in this type of cross-cultural science education; and how to best present different ways of knowing how nature and our universe work (science) in a manner that provides a context for science educators and museum professionals. In this article, we share these and other lessons we have learned from the leadership perspective of bringing together such a diverse and under-represented-in-science group of educators.

Peticolas, L. M.; Maryboy, N.; Begay, D.; Paglierani, R.; Frappier, R.; Teren, A.

2011-09-01

111

The Descent of the Serpent: Using a Successful Ancient Solar Observatories Webcast from Chichen Itza to Highlight Space Weather Research  

Microsoft Academic Search

Over the past seven years, NASA's Sun-Earth Connection Education Forum has sponsored and coordinated education and public outreach events to highlight NASA's heliophysics research and discoveries. Our strategy involves using celestial events, such as total solar eclipses and the Transit of Venus, as well as Sun-Earth Day during the March Equinox, to engage K-12 schools and the general public in

I. Hawkins; R. Higdon; T. Cline

2006-01-01

112

Molecular phylogeny of the Australian venomous snake genus Hoplocephalus (Serpentes, Elapidae) and conservation genetics of the threatened H. stephensii  

Microsoft Academic Search

The Australian elapid snakeHoplocephalus stephensii (Stephens' BandedSnake) is patchily distributed in disjunctforest remnants in eastern Australia and islisted as threatened in both states in which itoccurs (Qld and NSW). Here we focus on thephylogeography of H. stephensii toaddress (1) the genetic distinctiveness of thistaxon within its genus and (2) the level ofgenetic diversity present within and betweendisjunct populations from throughout

Scott J. Keogh; Ian A. W. Scott; Mark Fitzgerald; Richard Shine

2003-01-01

113

Phylogeography across a continent: The evolutionary and demographic history of the North American racer (Serpentes: Colubridae: Coluber constrictor)  

Microsoft Academic Search

Most phylogeographic studies examine organisms that do not have transcontinental distributions and therefore the genetic and temporal effects of barriers across an entire continent cannot be assessed with respect to a single species. We examined the phylogeographic structure, lineage age, and historical demography using sequences from the mtDNA cytochrome b gene of the widespread North American racer (Coluber constrictor), one

Frank T. Burbrink; Frank Fontanella; R. Alexander Pyron; Timothy J. Guiher; Cynthia Jimenez

2008-01-01

114

Phylogeography across a continent: the evolutionary and demographic history of the North American racer (Serpentes: Colubridae: Coluber constrictor).  

PubMed

Most phylogeographic studies examine organisms that do not have transcontinental distributions and therefore the genetic and temporal effects of barriers across an entire continent cannot be assessed with respect to a single species. We examined the phylogeographic structure, lineage age, and historical demography using sequences from the mtDNA cytochrome b gene of the widespread North American racer (Coluber constrictor), one of the few abundant transcontinental snakes that occurs throughout many diverse biomes. Our results indicate that this complex is comprised of six lineages differing greatly in geographic extent, with the largest (a central US clade) being approximately 26 times greater than the smallest (a lineage restricted to the Florida Panhandle and nearby portions of adjacent States). Most of the six lineages appear to be separated at previously identified genetic barriers for several vertebrates with similar ranges. Lineage diversification in this species began in the late Miocene, separating populations in the Florida Peninsula from the remainder of the US. Diversification of lineages continued throughout the Pliocene and early Pleistocene. Four of the six lineages occur east of the Mississippi River, with only two distinctly young ( approximately 1.5 mya) lineages found west of the Mississippi River (one occurs west of Continental Divide). All methods of demographic inference, including the mismatch distribution, Fu and Li's D and Tajima's D , and Bayesian skyline plots revealed population expansion occurring in the mid-to-late Pleistocene for every lineage, regardless of size or proximity to formerly glaciated areas. Population expansion for lineages found east of the Mississippi River occurred earlier and was much greater than those found west of the River. PMID:18093846

Burbrink, Frank T; Fontanella, Frank; Alexander Pyron, R; Guiher, Timothy J; Jimenez, Cynthia

2008-04-01

115

Two additional Hepatozoon species (Apicomplexa: Hepatozoidae) from the southern black racer, Coluber constrictor priapus (Serpentes: Colubridae), in northern Florida.  

PubMed

Hepatozoon priapus n. sp. from Coluber constrictor priapus has robust gamonts with broadly rounded ends, 18.0 x 4.2 microm (17.0-20.0 x 3.5-6.0), with LW 76.4 microm2 (59-105) and L/W 4.31 (2.9-5.4). The nucleus is always present in second quarter of gamont, seldom extend into first quarter but often into third quarter, 6.0 x 3.0 (5.0-7.0 x 2.5-4.0), with LW 17.9 (13.7-21.0). Erythrocyte cytoplasm is always thin, appearing dehemoglobinized, with infected cells always distorted. Infected erythrocytes are much longer and wider than uninfected cells, with longer nuclei. Oocysts are spherical to ovoid, 92.5 x 86.0 (55-123 x 47-115) and L/W 1.08 (1.0-1.3), contain 14.0 (6-31) sporocysts. Sporocysts, which are also spherical to ovoid, 26.3 x 23.3 (19-50 x 16-38), LW 641.2 (320-1,500) and L/W 1.13 (1.0-2.2), contain 12.6 (5-18) sporozoites. Hepatozoon confusus n. sp., also from C. constrictor priapus, has slender gamonts with rounded ends, 15.6 x 4.1 (14.0-17.0 x 3.5-5.0), with LW 64.3 (52-80) and L/W 3.82 (2.8-4.4). The nucleus is always present in second quarter of gamont, commonly extending into first and third quarters, 5.0 x 2.7 (2.5-4.4 x 4.0-6.0), with LW 13.5 (11.0-16.5). Erythrocyte cytoplasm is sometimes thin, appearing partially dehemoglobinized, with infected cells usually distorted. Infected erythrocytes are longer than uninfected cells but similar in width, with erythrocyte nuclei longer. Oocysts are spherical to ovoid, 115.5 x 108.9 (52-278 x 50-278), with L/W 1.06 (1.0-1.2), and contain 25.0 (7-111) sporocysts. Sporocysts are spherical to ovoid, 27.6 x 25.2 (21-38 x 20-33), LW 701.3 (420-1,125) and L/W 1.09 (1.0-1.4), containing 20.2 (12-32) sporozoites. PMID:15856888

Telford, Sam R; Butler, J F; Moler, Paul E

2005-02-01

116

The Scientific and Environmental ROV Partnership using Exisiting iNdustrial Technology The Newsletter of the SERPENT Project  

E-print Network

made at the workshop, which can be viewed on the Web at http://www.cdc.noaa.gov/~bem/ECMWF2001.htm and diabatic processes reside deep inside atmosphere models, where their control parameters act as a major the weakest links in the chain of parameterization efforts. Figure 1: Schematic of the parts of a model

National Oceanography Centre, Southampton

117

Sea snakes in Australian waters (Serpentes: subfamilies Hydrophiinae and Laticaudinae)-a review with an updated identification key.  

PubMed

Sea snakes (Elapidae, subfamilies Hydrophiinae and Laticaudinae) reach high species richness in the South China Sea and in the Australian region; however, most countries in the two regions still lack up-to-date checklists and identification tools for these snakes. We present an updated reviewed checklist and a new complete identification key to sea snakes in Australian waters. The identification key includes 29 species documented and 4 possibly occurring taxa and is based mostly on easy-to-use external characters. We find no evidence for breeding populations of Laticauda in Australian waters, but include the genus on the list of possibly occurring taxa.  PMID:25283923

Rasmussen, Arne Redsted; Sanders, Kate Laura; Guinea, Michael L; Amey, Andrew P

2014-01-01

118

A new species of triadal coral snake of the genus Micrurus Wagler, 1824 (Serpentes: Elapidae) from northeastern Brazil.  

PubMed

The genus Micrurus comprises 123 currently recognized taxa (species and subspecies) that are traditionally arranged in four species groups diagnosable mainly by color pattern characteristics. Here, we describe a new species of triadal coral snake from northeastern Brazil. The new species is distinguished from other sympatric triadal congeners (M. lemniscatus carvalhoi, M. ibiboboca and M. brasiliensis) mainly by the entirely black parietals and by a suite of external characters and hemipenial morphology. The new species appears to be restricted to tropical ombrophilous lowland coastal forests of northeastern Brazil and all recently collected specimens are known to occur in small forest patches surrounded by periurban environment, which calls for an urgent evaluation on its conservation status. PMID:24943187

Pires, Matheus Godoy; Da Silva, Nelson Jorge; Feitosa, Darlan Tavares; Prudente, Ana Lúcia Da Costa; Filho, Gentil Alves Pereira; Zaher, Hussam

2014-01-01

119

In Brief . . . No sooner it seems than we get the Christmas and New Year celebrations over, it's suddenly time for the next edition of  

E-print Network

Deep Seas. The SERPENT brand is undergoing a transformation with the launch of our new logo, so look events where you can have a go on the simulator yourself! The SERPENT Project National Oceanography takes to the road. Visit a venue and you can have a go yourself! Mark Benfield of GOM SERPENT reports

National Oceanography Centre, Southampton

120

Redescription of Haemogregarina garnhami (Apicomplexa: Adeleorina) from the blood of Psammophis schokari (Serpentes: Colubridae) as Hepatozoon garnhami n. comb. based on molecular, morphometric and morphologic characters.  

PubMed

Hepatozoon garnhami n. comb. was redescribed from Schokari sand snakes (Psammophis schokari) collected from Riyadh city in Saudi Arabia. Gametocytes were found in the peripheral blood of 2 of 15 snakes examined. Based on the similar morphological and morphometric characteristics, the same host and a similar host habitat environment, it can be concluded for the first time that the present species is conspecific with Haemogregarina garnhami previously reported from Psammophis shokari aegyptius. To further characterize this parasite, the partial 18S rRNA gene was amplified and sequenced. The sequence analysis also showed that Haemogregarina garnhami should be reassigned into the genus Hepatozoon as Hepatozoon garnhami which has 99.5% (859/863 bp) sequence similarity to Hepatozoon ayorgbor, infecting the erythrocytes of Python regius in Ghana. Phylogenetic analysis showed that H. garnhami formed a mixed clade with Hepatozoon spp. from geckos, snakes and rodents and ophidian Hepatozoon spp. did not form a separated phylogenetic unit. Also, Psammophis schokari-infecting Hepatozoon contained several different genetic lineages. To our knowledge, the present work extends the geographic distribution of H. garnhami and is the first report of Hepatozoon infection in snakes from Saudi Arabia. PMID:24827101

Abdel-Baki, Abdel-Azeem S; Al-Quraishy, Saleh; Zhang, J Y

2014-06-01

121

Population genetic structure and geographic differentiation in the hot spring snake Thermophis baileyi (Serpentes, Colubridae): indications for glacial refuges in southern-central Tibet.  

PubMed

The endangered hot spring snake (Thermophis baileyi) is endemic to the Tibetan Plateau and restricted to a few sites at high altitudes (>3500 m a.s.l.). Its strong preference for habitats with hot springs might be an early adaptation to the cooling climate during the plateau uplift. Some of these thermal sites may have been free of ice during the last glacial maximum (LGM) serving as refuges for the snake. To test this and to examine the population genetic structure data of 12 microsatellites and mitochondrial DNA were obtained from 153 individuals from 12 sites across the plateau. Four of the microsatellite loci were newly developed for this study. The results suggest that T. baileyi has at least two genetically diverse clades in Tibet, which developed during the Pleistocene and expanded after the LGM. Accordingly, the existence of separate glacial refuges on the central plateau can be assumed. Analyses of the genetic variation indicated a high level of geographic differentiation and population structure on a regional as well as on a range-wide scale. The study shows that, apart from the phylogeographic signatures, the diversification of current Thermophis populations is caused by (a) a limited dispersal due to mountain ranges, (b) a strong preference for hot springs and (c) the insular distribution of suitable habitats on the plateau. The present data should be taken into account in necessary monitoring and management plans for T. baileyi. PMID:22306823

Hofmann, Sylvia

2012-05-01

122

Phylogenetic relationships within Bothrops neuwiedi group (Serpentes, Squamata): geographically highly-structured lineages, evidence of introgressive hybridization and Neogene/Quaternary diversification.  

PubMed

Eight current species of snakes of the Bothrops neuwiedi group are widespread in South American open biomes from northeastern Brazil to southeastern Argentina. In this paper, 140 samples from 93 different localities were used to investigate species boundaries and to provide a hypothesis of phylogenetic relationships among the members of this group based on 1122bp of cyt b and ND4 from mitochondrial DNA and also investigate the patterns and processes occurring in the evolutionary history of the group. Combined data recovered the B. neuwiedi group as a highly supported monophyletic group in maximum parsimony, maximum likelihood and Bayesian analyses, as well as four major clades (Northeast I, Northeast II, East-West, West-South) highly-structured geographically. Monophyly was recovered only for B. pubescens. By contrast, B. diporus, B. lutzi, B. erythromelas, B. mattogrossensis, B. neuwiedi, B. marmoratus, and B. pauloensis, as currently defined on the basis of morphology, were polyphyletic. Sympatry, phenotypic intergrades and shared mtDNA haplotypes, mainly between B. marmoratus and B. pauloensis suggest recent introgressive hybridization and the possible occurrence of a narrow hybrid zone in Central Brazil. Our data suggest at least three candidate species: B. neuwiedi from Espinhaço Range, B. mattogrossensis (TM173) from Serra da Borda (MT) and B. diporus (PT3404) from Castro Barros, Argentina. Divergence estimates highlight the importance of Neogene events in the origin of B. neuwiedi group, and the origin of species and diversification of populations of the Neotropical fauna from open biomes during the Quaternary climate fluctuations. Data reported here represent a remarkable increase of the B. neuwiedi group sampling size, since representatives of all the current recognized species from a wide geographic range are included in this study, providing basic information for understanding the evolution and conservation of Neotropical biodiversity. PMID:24140980

Machado, Taís; Silva, Vinícius X; Silva, Maria José de J

2014-02-01

123

A phylogeny of the Lampropeltis mexicana complex (Serpentes: Colubridae) based on mitochondrial DNA sequences suggests evidence for species-level polyphyly within Lampropeltis  

Microsoft Academic Search

The systematic relationships of snakes in the Lampropeltis mexicana complex (L. mexicana, L. alterna, and L. ruthveni) are poorly known despite several taxonomic studies over the last 80 years. Mitochondrial DNA sequences were used to infer the phylogeny of the L. mexicana complex. At least one representative sample from the nine currently recognized species of Lampropeltis was sequenced. Our results

Robert W. Bryson Jr.; Jennifer Pastorini; Frank T. Burbrink; Michael R. J. Forstner

2007-01-01

124

A review of the uses of work-class ROVs for the benefits of science: Lessons learned from the SERPENT project  

E-print Network

Vol 26 A review of the uses of work-class ROVs for the benefits of science: Lessons learned from and Environmental ROV Partnership using Existing Industrial Technology) is a collaboration programme that was designed to make better use of remotely operated vehicle (ROV) technology and data available through links

National Oceanography Centre, Southampton

125

77 FR 15383 - Endangered Species; Receipt of Applications for Permit  

Federal Register 2010, 2011, 2012, 2013

...American alligator) Boidae (does not include Mona boa or Puerto Rican boa) Crocodylidae (does not include American crocodile) Emydidae Gekkonidae Iguanidae Pelomedusidae Testudinidae Trionychidae Varanidae Viperidae (includes Crotalus unicolor but not...

2012-03-15

126

BULLETIN OF THE UNITED STATRS FISH COMMISSION. 325 . 111-MONSTER SEA-HEEPENTS.  

E-print Network

sea-serpent story was not worthier of credence than a storyabout ghosts. That particular ghost he thought he had laid. Sincethen all sorts of explanations of sea-serpent stories have been advanced the.story of a sea-creature Seen swiftly advancing against wind nnd sea, at a distan~eof less than 200

127

NAGAS IN THE SCULPTURAL DECORATIONS OF EARLY WEST ORISSAN TEMPLES  

Microsoft Academic Search

The Nagas are mentioned in the Puranas as a race of serpents who were inhabiting the Patalaloka or the nether regions. We find descriptions on the origin of the Nagas in the Mahabharata and also in the Varaha Purana, according to which Rsi Kasyapa begot the seven great serpents Vasuki, Taksaka, Karkotaka, Padma, Mahapadma, Sankhapala and Kulika by Daksayani, the

Sasanka Sekhar Panda

128

ROV PACK: INFORMATION AND GUIDELINES www.serpentproject.com  

E-print Network

ROV PACK: INFORMATION AND GUIDELINES www.serpentproject.com SERPENT Project Office 496/02 National © 2008, SERPENT. CONFIDENTIAL. ALL RIGHTS RESERVED. #12;ROV PACK: INFORMATION AND GUIDELINES www WELCOME! A BRIEF INTRODUCTION 3 OUR DEEPWATER MISSION 3 OUR PRIORITIES 3 ROV PACKS 4 OUR LOCATIONS 5 AIMS

National Oceanography Centre, Southampton

129

On first reliable record of the sea snake Chitulia belcheri (Gray, 1849) from Australian waters, with notes on species composition and taxonomic status of the genus Chitulia (Serpentes, Hydrophiidae)  

Microsoft Academic Search

A description of the first reliable record of the rare sea snake Chitulia belcheri from Australian waters (Arafura Sea) is given. The species composition of the genus Chitulia and its taxonomic status in the genus group Hydrophis sensu lato (Leisoelasma, Chitulia, Polyodontognathus, and Hydrophis sensu stricto) are discussed. A revised key to the species of the genus Chitulia is provided.

V. E. Kharin; V. P. Cheblukov

2007-01-01

130

The Seminole Serpent Warrior At Miramar, FL, Shows Settlement Locations Enabled Environmental Monitoring Reminiscent Of the Four-corners Kokopelli-like EMF Phenomena, and Related to Earthquakes, Tornados and Hurricanes  

Microsoft Academic Search

Certain Native Americans of the past seem to have correctly deduced that significant survival information for their tradition-respecting cultures resided in EMF-based phenomena that they were monitoring. This is based upon their myths and the place or cult-hero names they bequeathed us. The sites we have located in FL have been detectable by us visually, usually by faint blue light,

Chan Balam Matagamon; Sagamo Pawa Matagamon

2004-01-01

131

The Seminole Serpent Warrior At Miramar, FL, Shows Settlement Locations Enabled Environmental Monitoring Reminiscent Of the Four-corners Kokopelli-like EMF Phenomena, and Related to Earthquakes, Tornados and Hurricanes.  

NASA Astrophysics Data System (ADS)

Certain Native Americans of the past seem to have correctly deduced that significant survival information for their tradition-respecting cultures resided in EMF-based phenomena that they were monitoring. This is based upon their myths and the place or cult-hero names they bequeathed us. The sites we have located in FL have been detectable by us visually, usually by faint blue light, or by the elicitation of pin-like prickings, by somewhat intense nervous-system response, by EMF interactions with aural electrochemical systems that can elicit tinitus, and other ways. In the northeast, Cautantowit served as a harbinger of Indian summer, and appears to be another alter ego of the EMF. The Miami, FL Tequesta site along the river clearly correlates with tornado, earthquake and hurricane locations. Sites like the Mohave Deserts giant man may have had similar significance.

Balam Matagamon, Chan; Pawa Matagamon, Sagamo

2004-03-01

132

Phan Anh Tu Member of ASF cohort VIIth THE SIGNIFICATION OF NAGA IN THAI ARCHITECTURAL  

E-print Network

Asian region and Naga of Indian religions in ancient times. It seems that the remains of indigenous and the Northwest of Vietnam) and the North of Thailand usually tattoo the water serpent on their back and arm

Baez, John

133

The Daily Echo Saturday, March 4, 2006 Page 19 ReviewThe SATURDAY NEWS REVIEW SECTION STORIES BEHIND THE NEWS plus PUZZLES & FIND THE BALL  

E-print Network

to SERPENT Project leader Ian Hudson, pictured. SSEECCRREETTSS OOFF TTHHEE DDEEEEPP COUNCIL TAX LOSERS: Page access to more than 100 oil rigs through the world's biggest drilling company, Transocean, alone. Partner

National Oceanography Centre, Southampton

134

77 FR 13147 - U.S. Nominations to the World Heritage List; 15-Day Notice of Opportunity for Public Comment  

Federal Register 2010, 2011, 2012, 2013

...properties on the Tentative List: The Frank Lloyd Wright Buildings and Poverty Point State...Newark and Heath, including: --Wright Earthworks --The Octagon Earthworks...Cabras) Serpent Mound, Ohio Wright (Frank Lloyd) Buildings [Selected To...

2012-03-05

135

75 FR 77901 - 30-Day Notice of Opportunity for Public Comment on U.S. Nominations to the World Heritage List...  

Federal Register 2010, 2011, 2012, 2013

...Dayton --Wright Hall (housing the Wright Flyer III), Dayton --Hawthorn...Newark and Heath, including: --Wright Earthworks --The Octagon Earthworks...las Cabras) Serpent Mound, Ohio Wright (Frank Lloyd) Buildings Taliesin West,...

2010-12-14

136

Neutralizing potency of horse antibothropic Brazilian antivenom against Bothrops snake venoms from the Amazonian rain forest.  

PubMed

Neutralization of lethal toxicity (50% effective dose; ED(50)), hemorrhagic (minimum hemorrhagic dose; MHD) and hemolytic activity (PLA(2)) and levels of antibodies, measured by enzyme-linked immunosorbent assay (ELISA), were investigated to test the potency of horse antibothropic serum (ABS) against Bothrops venoms from the Amazonian rain forest. ABS neutralized the lethal activity with a potency (mg of venom neutralized per 1 ml of antivenom) of 5.5, 3.7, 1.6, 1.3 and 6.5, respectively, for B. jararaca (reference venom for assessing the ABS potency in Brazil), B. atrox, B. brazili, B. bilineatus smaragdinus and B. taeniatus venoms. The volume of antivenom (microl) that neutralized one MHD of B. jararaca, B. atrox, B. brazili, B. bilineatus smaragdinus and B. taeniatus venoms was 5, 7.71, 7.76, 8.3 and 5, respectively. ABS neutralized the PLA(2) activity with a potency of 6.2, 3.2, 1.4, 2.6 and 5 respectively, for B. jararaca, B. atrox, B. brazili, B. bilineatus smaragdinus and B. taeniatus venoms. ELISA reactivity of ABS against the separate venoms was found to be quite variable. The reactivity against B. jararaca venom was higher than against other Bothrops venoms. In conclusion, the assays described here suggest that Brazilian Bothrops polyspecific antivenom is not very efficient in neutralizing the effects of venom from some Amazonian Bothrops species. PMID:10858523

Muniz, E G; Maria, W S; Estevão-Costa, M I; Buhrnheim, P; Chávez-Olórtegui, C

2000-12-01

137

Horizontal transfer of non-LTR retrotransposons in vertebrates  

Microsoft Academic Search

Since their discovery in family Bovidae (bovids), Bov-B LINEs, believed to be order-specific SINEs, have been found in all\\u000a ruminants and recently also in Viperidae snakes. The distribution and the evolutionary relationships of Bov-B LINEs provide\\u000a an indication of their origin and evolutionary dynamics in different species. The evolutionary origin of Bov-B LINE elements\\u000a has been shown unequivocally to be

Dušsan Kordišs; Franc Gubenšsek

1999-01-01

138

Asclepius, Caduceus, and Simurgh as medical symbols, part I.  

PubMed

This is the first of two articles reviewing the history of medical symbols. In this first article I have briefly reviewed the evolution of the Greek god, Asclepius, (and his Roman counterpart Aesculapius) with the single serpent entwined around a wooden rod as a symbol of western medicine and have alluded to the misplaced adoption of the Caduceus of the Greek god Hermes (and his Roman counterpart Mercury) with its double entwined serpents as an alternative symbol. In the second part of this article (to be published later), I have made a tentative suggestion of why the Simorgh might be adopted as an Eastern or an Asian symbol for medicine. PMID:20039773

Nayernouri, Touraj

2010-01-01

139

Traductions bibliques opposes Il est difficile de traduire la Bible. L'Ancien Testament est crit en hbreu  

E-print Network

pourquoi le serpent, Satan, est qualifié de menteur : non seulement il dit à Eve qu'ils ne mourront pas en puissance verbale de Satan, qui halshs-00449964,version1-24Jan2010 #12;trompe jusqu'aux traducteurs

Paris-Sud XI, Université de

140

Eastern Diamondback Rattlesnake  

E-print Network

, important members of their ecosystem, just like other animals. Although the snakes are NOT mean it was the biggest snake I had ever seen in the wild. The huge serpent was inching across the asphalt like rattlesnake -- was just yards away. As we approached the snake at a safe distance, I noticed it shift its huge

Georgia, University of

141

Did Indians of the Americas Preserve Linguistic Place-names Like Willimantic, CT, Indicating Some Islamic Interactions and Applied Physics Use, Before Columbus?  

Microsoft Academic Search

Modern Peruvians document: ``Ñari Huallac is the name of the town in the north of Peru (Piura) where our families come from. The words Ñari Huallac mean Serpent God, [editorial emphasis by underlining script is added], and are some of the few words which remain from the ancient Tallan civilization.'' Tallan seems related to The God, Allah, of Islam, as

Erica Crory; Roger D. Mc Leod

2007-01-01

142

Performance Analysis of AES candidates on the 6805 CPU core  

Microsoft Academic Search

The AES candidate block ciphers Crypton, Mars, RC6, Rijndael, and Serpent were implemented on the Motorola 6805 series 8-bit architecture. Their performance, including ROM and RAM sizes and time to encrypt a single block, was measured in simulation, and the results presented and compared with results for the other NIST cryptography algorithms SHA and DEA and previously published results for

Geoffrey Keating

1999-01-01

143

Radium226 in cattails, Typha latifolia, and bone of muskrat, Ondatra zibethica (L.), from a watershed with uranium tailings near the city of Elliot Lake, Canada  

Microsoft Academic Search

Radium-226 concentrations were measured in the main food plants (cattails, Typha latifolia) and bone of adult muskrats (Ondatra zibethica (L.)), taken from a study area near Quirke Lake in the Serpent River drainage basin. This watershed receives drainage containing radionuclides from the U tailings near the City of Elliot Lake, Ontario, Canada. Two control sites (one local, one 130 km

M. A. Mirka; F. V. Clulow; N. K. Davé; T. P. Lim

1996-01-01

144

Asclepius, Caduceus, and Simurgh as Medical Symbols Part I  

Microsoft Academic Search

This is the first of two articles reviewing the history of medical symbols. In this first article I have briefly reviewed the evolution of the Greek god, Asclepius, (and his Roman counterpart Aesculapius) with the single serpent entwined around a wooden rod as a symbol of western medicine and have alluded to the misplaced adoption of the Caduceus of the

Touraj Nayernouri

145

GreenWingsGreenWingsGreenWingsGreenWings Brian Wyvill  

E-print Network

was that Greenwings did not eat maidens. In fact he had never developed a taste for flesh of any kind, in short he was such a dragon. He had all the required dragon characteristics. A huge serpent covered in scales, enormous teeth which filled his fiercesome mouth. He had fiery breath, particularly when he didn't clean his teeth

Wyvill, Brian

146

1999 Macmillan Magazines Ltd ost snakes transport prey through  

E-print Network

) are tiny, burrowing serpents that feed pre- dominantly on the larvae, pupae and adults of social insects3, are difficult to main- tain in captivity. As a result, little is known about their natural history or about how of Leptotyphlops can repel some species of ant9 , this effect is variable, and selection is likely to favour

Brainerd, Elizabeth

147

Sea snakes: overlooked predators at a urban fringing reef Fig. 1 a Horned sea snake (Acalyptophis peronii) in Baie des  

E-print Network

the city of Nouméa. Baie des Citrons, the most popular beach in the city, harbours a sizeable resident. University Park Press, Baltimore, pp. 217-232 Shine R (2005) All at sea: aquatic life modifies mate (Serpentes, Hydrophiidae): the effects of sex, body size, and color pattern. Biol J Linn Soc 80:1­10 P. Borsa

Paris-Sud XI, Université de

148

A genome-wide RNA interference screen identifies a differential role of the mediator CDK8 module subunits for GATA/ RUNX-activated transcription in Drosophila.  

PubMed

Transcription factors of the RUNX and GATA families play key roles in the control of cell fate choice and differentiation, notably in the hematopoietic system. During Drosophila hematopoiesis, the RUNX factor Lozenge and the GATA factor Serpent cooperate to induce crystal cell differentiation. We used Serpent/Lozenge-activated transcription as a paradigm to identify modulators of GATA/RUNX activity by a genome-wide RNA interference screen in cultured Drosophila blood cells. Among the 129 factors identified, several belong to the Mediator complex. Mediator is organized in three modules plus a regulatory "CDK8 module," composed of Med12, Med13, CycC, and Cdk8, which has long been thought to behave as a single functional entity. Interestingly, our data demonstrate that Med12 and Med13 but not CycC or Cdk8 are essential for Serpent/Lozenge-induced transactivation in cell culture. Furthermore, our in vivo analysis of crystal cell development show that, while the four CDK8 module subunits control the emergence and the proliferation of this lineage, only Med12 and Med13 regulate its differentiation. We thus propose that Med12/Med13 acts as a coactivator for Serpent/Lozenge during crystal cell differentiation independently of CycC/Cdk8. More generally, we suggest that the set of conserved factors identified herein may regulate GATA/RUNX activity in mammals. PMID:20368357

Gobert, Vanessa; Osman, Dani; Bras, Stéphanie; Augé, Benoit; Boube, Muriel; Bourbon, Henri-Marc; Horn, Thomas; Boutros, Michael; Haenlin, Marc; Waltzer, Lucas

2010-06-01

149

Intelligence in Animals---Can a Viper Commit Suicide?  

Microsoft Academic Search

HAVING occasionally caught a viper, and kept it for a time in a glass case, one of the platelayers called me last Thursday and said ``there was a fine `Long Cripple' (a local name for a serpent of any kind) lying on the bank a few yards down the line.'' I went to the place indicated, and there was a

R. Langdon

1883-01-01

150

The symbol of modern medicine: why one snake is more than two.  

PubMed

Today, two serpent motifs are commonly used to symbolize the practice and profession of medicine. Internationally, the most popular symbol of medicine is the single serpent-entwined staff of Asklepios (Latin, Aesculapius), the ancient Greco-Roman god of medicine. However, in the United States, the staff of Asklepios (the Asklepian) and a double serpent-entwined staff with surmounting wings (the caduceus) are both popular medical symbols. The latter symbol is often designated as the "medical caduceus" and is equated with the ancient caduceus, the double serpent-entwined staff of the Greco-Roman god Hermes (Latin, Mercury). Many physicians would be surprised to learn that the medical caduceus has a quite modern origin: Its design is derived not from the ancient caduceus of Hermes but from the printer's mark of a popular 19th-century medical publisher. Furthermore, this modern caduceus became a popular medical symbol only after its adoption by the U.S. Army Medical Corps at the beginning of the 20th century. This paper describes the ancient origin of the Asklepian and how a misunderstanding of ancient mythology and iconography seems to have led to the inappropriate popularization of the modern caduceus as a medical symbol. PMID:12693891

Wilcox, Robert A; Whitham, Emma M

2003-04-15

151

Animal Symbols in the Art of the Hodensaunee.  

ERIC Educational Resources Information Center

Explains the significance of the main animal symbols incorporated into the social, cultural, artistic, and spiritual fabric of the Hodenosaunee (the People of the Longhouse) also known as the Six Nations Iroquois: the eagle, turtle, bear, wolf, hawk, heron, snipe, eel, deer, beaver, moose, snake, and serpent. (NEC)

Hill, Richard

1987-01-01

152

In Brief . . . Send us your stories!  

E-print Network

innovation research education 1 SERPENT The Scientific and Environmental ROV Partnership using Exisiting i Morvin Norway May 02 - 07 Andrew Gates Yes Science New Stena Carron mission images The Oceaneering ROV ( ) swims lazily away as the ROV approaches. Right: A curious Dumbo Squid (Cirroteuthiidae) watches us as we

National Oceanography Centre, Southampton

153

www.serpentproject.com issue 14: june 2008  

E-print Network

Hydro, the Norwegian gas and oil company and Oceaneering, a world leading ROV company, designed and delivered a highly opportunity to show children how the SERPENT project uses industrial Remotely Operated Vehicles (ROVs) to do at Oceaneering's high-tech ROV (Remotely Operated Vehicle) MIMIC simulation suite at the Stavanger facility

National Oceanography Centre, Southampton

154

Reproduced from Underwater Contractor International A collaboration between Southampton  

E-print Network

beyond the depths at which divers can operate. Operations rely heavily on ROV support, which is pro platforms operated by Transocean. As part of the SERPENT (Scientific and Environmen- tal ROV Partnership- nent Subsea 7 Pioneer HD work-class ROV on board the deepwater semi-submersible drilling rig Paul B

National Oceanography Centre, Southampton

155

CYRANO CAST LIST: All Cast members need to be measured in the costume shop before semester break. Please  

E-print Network

CYRANO CAST LIST: All Cast members need to be measured in the costume shop before semester break: Anna Morreale #12;The Serpent Lady Cast List FARRUSCAD; Casey James CHERESTANI; Adia Alli CANZADE/s CHERESTANI); Katherine Schooler FULMINA; Jenna Jo Pawlicki TERRAMOTA; Marley Boone Peter Pan Cast List PETER

Liu, Taosheng

156

Interior view, detail view of the balustrade; the balustrade is ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior view, detail view of the balustrade; the balustrade is cast bronze and consists of two ribbed posts alternating with a single post decorated with twisted serpents - New Post Office Building, Twelfth Street and Pennsylvania Avenue, Washington, District of Columbia, DC

157

AES Key Agility Issues in High-Speed IPsec Implementations  

Microsoft Academic Search

Some high-speed IPsec hardware systems need to support many thousands of security associations. The cost of switching among differen t encryption keys can dramatically affect throughput, particularly for the very common case of small packets. Three of the AES finalists (Rijndael, Serpent, and Twofish) provide very high key agility, as is required for such applications. The other two candidates (MARS,

Doug Whiting; Bruce Schneier; Steve Bellovin

2000-01-01

158

Inhibition of Hemorragic Snake Venom Components: Old and New Approaches  

PubMed Central

Snake venoms are complex toxin mixtures. Viperidae and Crotalidae venoms, which are hemotoxic, are responsible for most of the envenomations around the world. Administration of antivenins aimed at the neutralization of toxins in humans is prone to potential risks. Neutralization of snake venom toxins has been achieved through different approaches: plant extracts have been utilized in etnomedicine. Direct electric current from low voltage showed neutralizing properties against venom phospholipase A2 and metalloproteases. This mini-review summarizes new achievements in venom key component inhibition. A deeper knowledge of alternative ways to inhibit venom toxins may provide supplemental treatments to serum therapy. PMID:22069593

Panfoli, Isabella; Calzia, Daniela; Ravera, Silvia; Morelli, Alessandro

2010-01-01

159

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

NASA Astrophysics Data System (ADS)

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.

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

1999-11-01

160

Use of microarrays for investigating the subtoxic effects of snake venoms: insights into venom-induced apoptosis in human umbilical vein endothelial cells.  

PubMed

The pathological effects of only a small percentage of the total number of protein components of snake venoms are well documented, yet this knowledge has led to a general understanding of the physiological consequences of snake venom poisoning. The aim of this study was to assess the effect of subpathological levels of Crotalus atrox (Western diamondback rattlesnake) and Bothrops jararaca (Jararaca) snake venoms on the gene expression profile of human umbilical vein endothelial cells (HUVEC) in culture. Analysis of the data demonstrated that HUVECs treated with C. atrox venom had 33 genes up-regulated with significant fold changes of 1.5 or greater compared to untreated control cells. Ten genes were down-regulated with 1.5 or greater fold changes. In cells treated with B. jararaca venom, 33 genes were observed to be up-regulated and 11 genes were down-regulated with a fold change of 1.5 or more. More than half of the up-regulated genes and approximately half of the down-regulated genes detected in cells treated with the venoms were found in both data sets underscoring both the similarities and differences between the two venoms. Ontological categorization of the up-regulated genes from endothelial cells treated with either C. atrox or B. jararaca venom gave the cell growth/maintenance and signal transducer groups as having the most members. The ontology of the down-regulated genes from both venom-treated cell samples was more varied but interestingly, the predominant ontology class was also cell growth/maintenance. Many of the up-regulated genes are involved in the Fas ligand/TNF-alpha receptor apoptotic pathway. In summary, these experiments demonstrate the power of gene expression profiling to explore the subtoxic effects of venoms on gene expression and highlight its potential for the discovery of novel insights into a variety of biological processes and signal transduction pathways. Furthermore, these studies illustrate the subtle functional differences between similar venoms that are not always evident from standard analyses. PMID:12657312

Gallagher, Paul G; Bao, Yongde; Serrano, Solange M T; Kamiguti, Aura S; Theakston, R David G; Fox, Jay W

2003-03-01

161

Neutralization of the hemorrhagic activity of Bothrops and Lachesis snake venoms by a monoclonal antibody against mutalysin-II.  

PubMed

One mAb reactive with mutalysin-II, a hemorrhagic metalloproteinase isolated from Lachesis muta muta venom, was produced in mice immunized with L. m. muta venom. Indirect ELISA was employed to compare the antigenic cross-reactivity among the venoms from Bothrops snakes. The mAb anti-mutalysin-II efficiently neutralized the hemorrhagic effect of both mutalysin-II and L. m. muta crude venom. Furthermore, the mAb were cross-reactive with B. alternatus, B. atrox, B. itapetiningae, B. jararaca and B. neuwiedii and showed variable potencies in neutralizing the hemorrhagic activity of several bothropic venoms. PMID:10669019

Estêvão-Costa, M I; Martins, M S; Sánchez, E F; Diniz, C R; Chávez-Olórtegui, C

2000-01-01

162

On the role of competing word units in visual word recognition: The neighborhood frequency effect  

Microsoft Academic Search

Psychologie Expérimentale, 28 rue Serpente, 75006 Paris, France. Current models of word recognition generally assume that\\u000a word units orthographically similar to a stimulus word are involved in the visual recognition of this word. We refer to this\\u000a set of orthographically similar words as an orthographic neighborhood. Two experiments are presented that investigate the\\u000a ways in which the composition of this

Jonathan Grainger; J. Kevin O’regan; Arthur M. Jacobs; Juan Segui

1989-01-01

163

Does prey size induce head skeleton phenotypic plasticity during early ontogeny in the snake Boa constrictor ?  

Microsoft Academic Search

Diet was manipulated in juveniles of the snakeBoaconstrictor (Serpentes: Boidae) to test the hypothesis of whether prey size induces phenotypic plasticity of the head skeleton. Additionally, the onset of sexual size dimorphisms (SSDs) was determined under a feeding schedule where total prey mass consumed by snakes was held constant. Twenty-three neonatalB. constrictor from a single-sired litter were placed into two

Gordon W. Schuett; David L. Hardy Sr; Ryan L. Earley; Harry W. Greene

2005-01-01

164

The Sunlight Effect of the Kukulcán Pyramid or The History of a Line  

Microsoft Academic Search

When the sunlight bathes the Kukulcán Pyramid in the Mayan city of Chichén-Itzá during the equinox sunset, it casts seven\\u000a triangles of light and shadow that creep downwards along its northeast stairway. According to the Popol Vuh, the effect can be interpreted as the myth of the gods of the Heart of Sky coming to the Sovereign Plumed Serpent. Unfortunately,

Tomás García-Salgado

2010-01-01

165

Uptake of 5 9 Fe from soluble 5 9 Fe-humate complexes by cucumber and barley plants  

Microsoft Academic Search

The capability of cucumber (Cucumis sativus L., cv. Serpente cinese), a Strategy I plant and barley (Hordeum vulgaris L., cv. Europa), a Strategy II plant to use Fe complexed by a water-soluble humic fraction (WEHS) extracted from a peat, was studied. Uptake of 59Fe from 59Fe-WEHS by cucumber plants was higher at pH 6.0 than at pH 7.5. Roots of

S. Cesco; M. Nikolic; V. Römheld; Z. Varanini; R. Pinton

2002-01-01

166

Ophiuchus  

NASA Astrophysics Data System (ADS)

(the Serpent-bearer; abbrev. Oph, gen. Ophiuchi; area 948 sq. deg.) An equatorial constellation which lies between Hercules and Scorpius, and culminates at midnight in mid-June. The ecliptic cuts across the southern part of Ophiuchus, but the constellation is not included among the constellations of the zodiac. Ophiuchus is usually said to represent Asclepius, the Greek god of medicine, and is sh...

Murdin, P.

2000-11-01

167

"A fit soule": Italian influences upon Milton's Eve  

E-print Network

including Adam, Eve, God, Angels, and the Serpent. According to one of Milton' s biographers, "Milton pierc'd through the Absurdity of that Performance to the hidden Majesty of the Subject, which being altogether unfit for the Stage, yet might be (for...). An encomium written by the Roman, Salzilli, praises Milton: An Epigram, by Giovanni Salzilli, a Roman on John Milton, Englishman, who deserves a coronal fashioned of the triple laurel of poesy ? Greek, Latin, and Italian. Yield, Meles, yield; let Mincius...

Pennebaker, Mattie Katherine

2013-02-22

168

Patent frenzy!  

Microsoft Academic Search

The Ouroboros is a universal symbol. This iconic depiction of a serpent eating its own tail has been interpreted and re-interpreted by a diverse array of cultures, from Egypt, India, and Japan to the Aztecs and Native Americans. Had the ancient Egyptians filed for a patent with the U.S. Patent Office for the method of drawing said symbol, they'd probably

Aaron Weiss

2004-01-01

169

The conserved structure of snake venom toxins confers extensive immunological cross-reactivity to toxin-specific antibody.  

PubMed

We have demonstrated previously that antisera from mice immunised with DNA encoding the carboxy-terminal domain (JD9) of a potent haemorrhagic metalloproteinase, jararhagin, neutralised over 70% of the haemorrhagic activity of the whole Bothrops jararaca venom. Here, we demonstrate that the JD9-specific antibody possesses extensive immunological reactivity to venom components in snakes of distinct species and genera. The polyspecific immunological reactivity of the antibody showed a correlation with amino acid sequence identity and with predicted antigenic domains of JD9-analogues in venoms of snakes with closest phylogenetic links to B. jararaca. This study further promotes the potential of DNA immunisation to generate toxin-specific antibodies with polyspecific cover. An analysis of the reactivity of the JD9-specific antisera to B. atrox complex venoms that exhibited intraspecific variation in the venom proteome revealed, however, that the toxin-specific approach to antivenom development requires a more in-depth knowledge of the target molecules than is required for conventional antivenoms. PMID:12657313

Harrison, R A; Wüster, W; Theakston, R D G

2003-03-01

170

Two related thrombin-like enzymes present in Bothrops atrox venom.  

PubMed

This article describes the presence of two new forms of a thrombin-like enzyme, both with apparent molecular masses of 38 kDa, in Bothrops atrox venom. Both share the ability to cleave fibrinogen into fibrin and to digest casein. Both present identical K(m) on the substrate BApNA. Their N-terminal amino acid sequences are identical for 26 residues, sharing 80% homology with batroxobin and flavoxobin. Two groups of monoclonal antibodies (mAbs) raised against the purified enzyme forms recognized different epitopes of the putative corresponding enzymes present in B. atrox crude venom. On Western blotting analysis of B. atrox crude venom, mAbs 5DB2C8, 5AA10 and 5CF11, but not mAbs 6CC5 and 6AD2-G5, revealed two or more protein bands ranging from 25 to 38 kDa. By immunoprecipitation assays, the 6AD2-G5 mAb was able to precipitate protein bands of 36-38 kDa from B. atrox, B. leucurus, B. pradoi, B. moojeni, B. jararaca and B. neuwiedii crude venoms. Fibrinogen-clotting activity was inhibited when the same venom specimens were pre-incubated with mAb 6AD2-G5, except for B. jararaca and B. neuwiedii. PMID:11050658

Petretski, J H; Kanashiro, M; Silva, C P; Alves, E W; Kipnis, T L

2000-11-01

171

Neutralization of bothropic and crotalic venom toxic activities by IgG(T) and IgGa subclasses isolated from immune horse serum.  

PubMed

IgG(T) and IgGa isotypes were isolated from horse hyperimmune anti-bothropic and anti-crotalic sera using a combination of two affinity chromatographic processes. IgG(T) and IgGa isotypes were isolated from these sera by chromatography on protein A-Sepharose followed by separation of the two isotypes by chromatography on a column of anti-IgG(T)-Sepharose. LO-HoGT-1, a rat anti-horse IgG(T) monoclonal antibody, was used. A comparative study of the efficiency of these isotypes in neutralizing the main toxic activities of the homologous venoms was carried out. It was found that IgG(T) was about three-fold and seven-fold more protective than IgGa for neutralization of the lethal activity of B. jararaca and C. d. terrificus venoms, respectively. IgG(T) was also more effective than IgGa for the neutralization of the haemorrhagic activity induced by B. jararaca venom, while both isotypes neutralized equally well the blood incoagulability induced by this venom. The results suggest that IgG(T) is the most protective isotype present in both anti-bothropic and anti-crotalic sera, followed by IgGa. Owing to their very low concentration in the serum, other IgG isotypes are not likely to be important in neutralizing the venoms' toxic activities. PMID:9241786

Fernandes, I; Takehara, H A; Santos, A C; Cormont, F; Latinne, D; Bazin, H; Mota, I

1997-06-01

172

Venomous snakebites.  

PubMed

More than 5 million people are bitten by venomous snakes annually and more than 100,000 of them die. In Europe, one person dies due to envenomation every 3 years. There is only one venomous snake species in Lithuania--the common adder (Vipera berus)--which belongs to the Viperidae family; however, there are some exotic poisonous snakes in the zoos and private collections, such as those belonging to the Elapidae family (cobras, mambas, coral snakes, etc.) and the Crotalidae subfamily of the Viperidae family (pit vipers, such as rattlesnakes). Snake venom can be classified into hemotoxic, neurotoxic, necrotoxic, cardiotoxic, and nephrotoxic according to the different predominant effects depending on the family (i.e., venom of Crotalidae and Viperidae snakes is more hemotoxic and necrotoxic, whereas venom of Elapidae family is mainly neurotoxic). The intoxication degree is estimated according to the appearance of these symptoms: 1) no intoxication ("dry" bite); 2) mild intoxication (local edema and pain); 3) moderate intoxication (pain, edema spreading out of the bite zone, and systemic signs); 4) severe intoxication (shock, severe coagulopathy, and massive edemas). This topic is relevant because people tend to make major mistakes providing first aid (e.g., mouth suction, wound incision, and application of ice or heat). Therefore, this article presents the essential tips on how first aid should be performed properly according to the "Guidelines for the Management of Snake-Bites" by the World Health Organization (2010). Firstly, the victim should be reassured. Rings or other things must be removed preventing constriction of the swelling limb. Airway/breathing must be maintained. The bitten limb should be immobilized and kept below heart level to prevent venom absorption and systemic spread. Usage of pressure bandage is controversial since people usually apply it improperly. Incision, mouth suction, or excision should not be performed; neither a tourniquet nor ice or heat should be applied. A doctor must monitor respiratory rate, blood pressure, heart rate, renal function, fluid balance, and coagulation status. The only specific treatment method is antivenin--serum with antibodies against antigens of snake venom. Antivenins against pit vipers used in the United States are Antivenin Crotalidae Polyvalent (ACP) and a more purified and hence causing less adverse reactions--Crotalidae Polyvalent Immune Fab (CroFab). In Europe, a polyvalent antiserum against Viperidae family snakes (including the common adder) can be used. Antivenins often may cause severe hypersensitivity reactions because of their protein nature. The bite of the common adder (the only poisonous snake in such countries as Lithuania and Great Britain) relatively rarely results in death; thus, considering the risk of dangerous reactions the antivenin causes itself, the usage of it is recommended to be limited only to life-threatening conditions. PMID:22123554

Adukauskien?, Dalia; Varanauskien?, Egl?; Adukauskait?, Agn?

2011-01-01

173

Biochemical Characterization, Action on Macrophages, and Superoxide Anion Production of Four Basic Phospholipases A2 from Panamanian Bothrops asper Snake Venom  

PubMed Central

Bothrops asper (Squamata: Viperidae) is the most important venomous snake in Central America, being responsible for the majority of snakebite accidents. Four basic PLA2s (pMTX-I to -IV) were purified from crude venom by a single-step chromatography using a CM-Sepharose ion-exchange column (1.5 × 15?cm). Analysis of the N-terminal sequence demonstrated that pMTX-I and III belong to the catalytically active Asp49 phospholipase A2 subclass, whereas pMTX-II and IV belong to the enzymatically inactive Lys49 PLA2s-like subclass. The PLA2s isolated from Panama Bothrops asper venom (pMTX-I, II, III, and IV) are able to induce myotoxic activity, inflammatory reaction mainly leukocyte migration to the muscle, and induce J774A.1 macrophages activation to start phagocytic activity and superoxide production. PMID:23509779

Rueda, Aristides Quintero; Rodriguez, Isela Gonzalez; Arantes, Eliane C.; Setubal, Sulamita S.; Calderon, Leonardo de A.; Zuliani, Juliana P.; Stabeli, Rodrigo G.; Soares, Andreimar M.

2013-01-01

174

Neutralization of local and systemic toxicity of Daboia russelii venom by Morus alba plant leaf extract.  

PubMed

Antivenom therapy is the current best therapy available for the treatment of fatal snake envenomation. However, the antivenom offers less or no protection against local effects such as extensive edema, hemorrhage, dermo-, myonecrosis and inflammation at the envenomed region. Viperidae snakes are highly known for their violent local effects and such effects have been commonly treated with plant extracts without any scientific validation in rural India. In this investigation Morus alba plant leaf extract has been studied against the Indian Vipera/Daboia russelii venom induced local and systemic effects. The extract completely abolished the in vitro proteolytic and hyaluronolytic activities of the venom. Edema, hemorrhage and myonecrotic activities were also neutralized efficiently. In addition, the extract partially inhibited the pro-coagulant activity and completely abolished the degradation of Aalpha chain of human fibrinogen. Thus, the extract processes potent antisnake venom property, especially against the local and systemic effects of Daboia russelii venom. PMID:19235141

Chandrashekara, K T; Nagaraju, S; Nandini, S Usha; Kemparaju, K

2009-08-01

175

Current challenges for confronting the public health problem of snakebite envenoming in Central America  

PubMed Central

Snakebite envenoming is a serious public health problem in Central America, where approximately 5,500 cases occur every year. Panama has the highest incidence and El Salvador the lowest. The majority, and most severe, cases are inflicted by the pit viper Bothrops asper (family Viperidae), locally known as ‘terciopelo’, ‘barba amarilla’ or ‘equis’. About 1% of the bites are caused by coral snakes of the genus Micrurus (family Elapidae). Despite significant and successful efforts in Central America regarding snakebite envenomings in the areas of research, antivenom manufacture and quality control, training of health professionals in the diagnosis and clinical management of bites, and prevention of snakebites, much remains to be done in order to further reduce the impact of this medical condition. This essay presents seven challenges for improving the confrontation of snakebite envenoming in Central America. Overcoming these challenges demands a coordinated partnership of highly diverse stakeholders though inter-sectorial and inter-programmatic interventions. PMID:24602234

2014-01-01

176

Venomous snakebite in Thailand. I: Medically important snakes.  

PubMed

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). PMID:9597848

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

1998-05-01

177

Comparative Sex Chromosome Genomics in Snakes: Differentiation, Evolutionary Strata, and Lack of Global Dosage Compensation  

PubMed Central

Snakes exhibit genetic sex determination, with female heterogametic sex chromosomes (ZZ males, ZW females). Extensive cytogenetic work has suggested that the level of sex chromosome heteromorphism varies among species, with Boidae having entirely homomorphic sex chromosomes, Viperidae having completely heteromorphic sex chromosomes, and Colubridae showing partial differentiation. Here, we take a genomic approach to compare sex chromosome differentiation in these three snake families. We identify homomorphic sex chromosomes in boas (Boidae), but completely heteromorphic sex chromosomes in both garter snakes (Colubridae) and pygmy rattlesnake (Viperidae). Detection of W-linked gametologs enables us to establish the presence of evolutionary strata on garter and pygmy rattlesnake sex chromosomes where recombination was abolished at different time points. Sequence analysis shows that all strata are shared between pygmy rattlesnake and garter snake, i.e., recombination was abolished between the sex chromosomes before the two lineages diverged. The sex-biased transmission of the Z and its hemizygosity in females can impact patterns of molecular evolution, and we show that rates of evolution for Z-linked genes are increased relative to their pseudoautosomal homologs, both at synonymous and amino acid sites (even after controlling for mutational biases). This demonstrates that mutation rates are male-biased in snakes (male-driven evolution), but also supports faster-Z evolution due to differential selective effects on the Z. Finally, we perform a transcriptome analysis in boa and pygmy rattlesnake to establish baseline levels of sex-biased expression in homomorphic sex chromosomes, and show that heteromorphic ZW chromosomes in rattlesnakes lack chromosome-wide dosage compensation. Our study provides the first full scale overview of the evolution of snake sex chromosomes at the genomic level, thus greatly expanding our knowledge of reptilian and vertebrate sex chromosomes evolution. PMID:24015111

Zektser, Yulia; Mahajan, Shivani; Bachtrog, Doris

2013-01-01

178

Time Correlations in Fluid Transport Obtained by Sequential Rephasing Gradient Pulses  

NASA Astrophysics Data System (ADS)

We present a basic experiment by which the evolution of the displacement probability density (propagator) of static or flowing fluid in Nsuccessive time intervals is obtained by single labeling, coupled with multiple rephasing events during the course of a pulsed field-gradient sequence. We term this type of sequence SERPENT: SEquential Rephasing by Pulsed field-gradients Encoding N Time-intervals. Realizations of the SERPENT experiment for the case N= 2 which include spin echo, stimulated echo, and Carr-Purcell pulse sequences are suggested. They have in common a spatial spin-labeling of the initial magnetization by a gradient of area q 0, followed by successive rephasing via gradients q 1and q 2at times t= ? 1and t= ? 2, respectively, where q 0+ q 1+ q 2= 0. A two-dimensional Fourier transform with respect to q 1and q 2gives directly the joint probability density W2(R 1, ? 1; R 2, ? 2) for displacements R 1and R 2in times ? 1and ? 2, respectively. q 1and q 2may be in arbitrary directions. Assuming R 1?R 2, the correlation coefficient ? R 1,R 2then reflects the time-history of the fluctuating velocities. The behavior of the cross moment can be obtained from either a full two-dimensional or a set of one-dimensional SERPENT measurements. Experimental results are presented for water flowing through a bed of packed glass beads. While ? 1is appropriately chosen to sample the short-time velocity field within the system, increasing ? 2clearly shows the loss of correlation when the average fluid element displacement exceeds the bead diameter.

Stapf, Siegfried; Damion, Robin A.; Packer, Ken J.

1999-04-01

179

Time Correlations in Fluid Transport Obtained by Sequential Rephasing Gradient Pulses.  

PubMed

We present a basic experiment by which the evolution of the displacement probability density (propagator) of static or flowing fluid in N successive time intervals is obtained by single labeling, coupled with multiple rephasing events during the course of a pulsed field-gradient sequence. We term this type of sequence SERPENT: SEquential Rephasing by Pulsed field-gradients Encoding N Time-intervals. Realizations of the SERPENT experiment for the case N = 2 which include spin echo, stimulated echo, and Carr-Purcell pulse sequences are suggested. They have in common a spatial spin-labeling of the initial magnetization by a gradient of area q0, followed by successive rephasing via gradients q1 and q2 at times t = Delta1 and t = Delta2, respectively, where q0 + q1 + q2 = 0. A two-dimensional Fourier transform with respect to q1 and q2 gives directly the joint probability density W2(R1, Delta1; R2, Delta2) for displacements R1 and R2 in times Delta1 and Delta2, respectively. q1 and q2 may be in arbitrary directions. Assuming R1 ||R2, the correlation coefficient rhoR1,R2 then reflects the time-history of the fluctuating velocities. The behavior of the cross moment can be obtained from either a full two-dimensional or a set of one-dimensional SERPENT measurements. Experimental results are presented for water flowing through a bed of packed glass beads. While Delta1 is appropriately chosen to sample the short-time velocity field within the system, increasing Delta2 clearly shows the loss of correlation when the average fluid element displacement exceeds the bead diameter. Copyright 1999 Academic Press. PMID:10089165

Stapf; Damion; Packer

1999-04-01

180

Amino acid sequence of a lectin-like protein from Lachesis muta stenophyrs venom.  

PubMed

The primary structure of the lectin-like protein from Lachesis muta stenophyrs venom was deduced from analysis of the N-terminus and the sequence of peptides obtained after digestion with trypsin, Arg-C enzyme, Staphylococcus aureus V8 protease and endoproteinase Asp-N. Peptides generated by cleavage of the lectin with cyanogen bromide and o-iodosobenzoic acid were also sequenced. Comparison of the complete 135 amino acid residues sequence with those of the lectin from the venom of Crotalus atrox, with platelet coagglutinin from Bothrops jararaca beta-fragment and with the anticoagulant B protein chain from Trimeresurus flavoviridis venom, revealed 92, 46 and 29% identity, respectively. Significant homology was also found with C-type carbohydrate-recognition domain-like structures from invertebrate and vertebrate lectins. To our knowledge, this is the second known primary structure of a lectin-like protein from snake venom. PMID:8843577

Aragón-Ortiz, F; Mentele, R; Auerswald, E A

1996-07-01

181

Malformations in neotropical viperids: qualitative and quantitative analysis.  

PubMed

Malformations can occur in all living species, but there is little information about anomalies that occur in snakes and their frequency. This study assessed malformations in newborn South American pit vipers (Bothrops jararaca) and South American rattlesnakes (Crotalus durissus) from wild captured pregnant females (240 and 35 litters, respectively). Newborn snakes were measured, weighed, sexed and studied grossly and by radiography for the presence of malformations. Ninety-five malformed pit vipers were identified from 4,087 births (2.3%), while 36 malformed rattlesnakes were found from 324 births (11.1%). Spinal abnormalities were the most common in both species, followed by fusion of ventral scales. Pit vipers showed a greater range of malformations including schistosomia (22.1%), kinked tail (13.7%), bicephaly (3.1%) and hydrocephaly (2.1%). PMID:23885804

Sant'Anna, S S; Grego, K F; Lorigados, C A B; Fonseca-Pinto, A C B C; Fernandes, W; Sá-Rocha, L C; Catão-Dias, J L

2013-11-01

182

Literary feature reviews  

Microsoft Academic Search

Letting history be the guide: writings by African?American womenThe Temple of My Familiar Alice Walker London: The Women's Press. 1989. 405pp. £12.95hb.Quicksand and Passing Nella Larsen London: Serpent's Tail. 1989. 277pp. £7.95pb.Corregidora Gayl Jones London: Camden Press. 1988. 185pp. £5.95pb.Bird at my Window Rosa Guy London: Virago. 1989. 282pp. £4.99pb.Lyrical Campaigns: selected poems June Jordan London: Virago. 1988. 143pp. £5.99pb.Moving

Margaret Busby; Giovanni Pontiero

1990-01-01

183

A Serrate-expressing signaling center controls Drosophila hematopoiesis  

PubMed Central

The differentiation of Drosophila blood cells relies on a functional hierarchy between the GATA protein, Serpent (Srp), and multiple lineage-specific transcription factors, such as the AML1-like protein, Lozenge (Lz). Two major branches of Drosophila hematopoiesis give rise to plasmatocytes/macrophages and crystal cells. Serrate signaling through the Notch pathway is critical in the regulation of Lz expression and the specification of crystal cell precursors, thus providing a key distinction between the two lineages. The expression of Serrate marks a discrete cluster of cells in the lymph gland, a signaling center, with functional similarities to stromal signaling in mammalian hematopoiesis. PMID:12569125

Lebestky, Tim; Jung, Seung-Hye; Banerjee, Utpal

2003-01-01

184

Isolation and Chemical Characterization of a Toxin Isolated from the Venom of the Sea Snake, Hydrophis torquatus aagardi  

PubMed Central

Sea snakes (family: Hydrophiidae) are serpents found in the coastal areas of the Indian and Pacific Oceans. There are two subfamilies in Hydrophiidae: Hydrophiinae and Laticaudinae. A toxin, aagardi toxin, was isolated from the venom of the Hydrophiinae snake, Hydrophis torquatus aagardi and its chemical properties such as molecular weight, isoelectric point, importance of disulfide bonds, lack of enzymatic activity and amino acid sequence were determined. The amino acid sequence indicated a close relationship to the primary structure of other Hydrophiinae toxins and a significant difference from Laticaudinae toxins, confirming that primary toxin structure is closely related to sea snake phylogenecity. PMID:22069538

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

2009-01-01

185

Literary reviews  

Microsoft Academic Search

Thinly?veiled autobiographyThe Enigma of Arrival. V S Naipaul, London: Viking. 1987. 318pp. £10.95hbUnmasking MexicoThe Good Conscience. Carlos Fuentes, London: André Deutsch. 1986. 148pp. £8.95hb\\/£3.95pbA Change of Skin. Carlos Fuentes, London: André Deutsch. 1986. 462pp. £6.95pbThe Old Gringo. Carlos Fuentes, London: André Deutsch. 1986. 199pp. £8.95Alternative realities: novels from BrazilDona Flor and Her Two Husbands. Jorge Amado, London: Serpent's Tail. 1986.

Johnt Hieme; Jason Wilson; Amanda Hopkinson; Nissa Torrents; Judie Newman; Maria Couto; William Walsh; Fadia A Faqir; M. M. Badawi; Shahrukh A Husain

1987-01-01

186

Women in the Early Spanish American Theatre.  

E-print Network

FALL 1970 23 Women in the Early Spanish American Theatre WILLIS KNAPP JONES Few will deny that the first actress to "strut her hour upon the stage" was Eve, the leading lady in the melodrama "The Apple and the Serpent, or How to Sin without... for almost 2,000 years a man's world, and was to know no women performers, even though the greatest creations in the Golden Age of Greek drama were women characters. It was a man, Polus, admired by Petrarch, who first enacted Electra in Sophocles' tragedy...

Jones, W. K.

1970-10-01

187

Improved Neutronics Treatment of Burnable Poisons for the Prismatic HTR  

SciTech Connect

In prismatic block High Temperature Reactors (HTR), highly absorbing material such a burnable poison (BP) cause local flux depressions and large gradients in the flux across the blocks which can be a challenge to capture accurately with traditional homogenization methods. The purpose of this paper is to quantify the error associated with spatial homogenization, spectral condensation and discretization and to highlight what is needed for improved neutronics treatments of burnable poisons for the prismatic HTR. A new triangular based mesh is designed to separate the BP regions from the fuel assembly. A set of packages including Serpent (Monte Carlo), Xuthos (1storder Sn), Pronghorn (diffusion), INSTANT (Pn) and RattleSnake (2ndorder Sn) is used for this study. The results from the deterministic calculations show that the cross sections generated directly in Serpent are not sufficient to accurately reproduce the reference Monte Carlo solution in all cases. The BP treatment produces good results, but this is mainly due to error cancellation. However, the Super Cell (SC) approach yields cross sections that are consistent with cross sections prepared on an “exact” full core calculation. In addition, very good agreement exists between the various deterministic transport and diffusion codes in both eigenvalue and power distributions. Future research will focus on improving the cross sections and quantifying the error cancellation.

Y. Wang; A. A. Bingham; J. Ortensi; C. J. Permann

2012-10-01

188

Polyarnye siyaniya sistemy avroral'nogo ovala kak kosmoloficheskij obraz drevnej mifologii %t The northern light of the auroral oval system as a cosmological concept of the archaic mythology  

NASA Astrophysics Data System (ADS)

Since archaic epochs people attentively observe the sky. They used to associate the sky phenomena with gods, heroes, spirits, etc. People interpreted the regularities in the motion of celestial objects in terms of their mythological model of the Universe. These observations and interpretations were first steps of the archaeoastronomy. Many remarkable features are inherent in the patterns of northern lights of the auroral oval system. Their manifestations are fairly regular. Did the ancients observe and some how classify these northern light phenomena? If yes, with which mythological personages were they associated? When were studies of the polar lights initiated? The present work is an attempt to answer these questions. We shall see that the ancient people assumed the spirit-world to be situated on the North. If so, it should manifest itself in spectacular polar aurorae. The specifically northern mythic cosmology formed the basis for Slavic fairy tales (theme of the Serpent and Serpent Fighter) and folk-beliefs. Other inhabitants of snowy latitudes should also manifest similar views. Studying the mythological reflections of typical auroral phenomena, it is possible to trace up long-standing ideological trends from the late glaciation epoch to the present time. Our results can help geophysicists in studying paleoauroral phenomena.

Alekseeva, L. M.

189

Is Continuing Contumely Relative to Mc Leod's Vision and ``Secret Sacred Science, (SSS),'': Contagiously Counterproductive in Science, or an Unhealthy Artifact of ``Turf Wars''?  

NASA Astrophysics Data System (ADS)

Mc Leod confirmed, with physics, his models for vision, and for electromagnetic artifacts, by traditional methods, associated with phenomena like tornados, hurricanes, and earthquakes. The latter confirmations are evidently apparent across current ethnology, cultures, linguistics, religion, rituals, exotic astronomy, somewhat concealed evidence of native record-keeping/writing, and iconography. Use of cultural anthropology while observing a modern Peruvian sacred-site-sweeping at Cuzco, coupled with their assertion that Ñari Huallac means ``serpent God,'' plus electromagnet information, reveals that their religious world-view include(s)(d) applied science that is still otherwise unacknowledged. Alexander Thom's precise megalithic site-measurements also imply that ``The Ancients' Serpent'' made/makes precise tracks that convey valuable information. The linguistics of words like Seminole, and unusual visual effects, reveal some traditionalists have done better than most scientists, for vision, and observational physics, and earth science. Tornado and hurricane tracks are predictable, as are some earthquakes. Tornado ``detuning'' or shutdown is electromagnetically possible. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.NES07.C2.7

Leod, Roger

2007-04-01

190

Mars Hand Lens Imager (MAHLI) Efforts and Observations at the Rocknest Eolian Sand Shadow in Curiosity's Gale Crater Field Site  

NASA Technical Reports Server (NTRS)

The Mars Science Laboratory (MSL) mission is focused on assessing the past or present habitability of Mars, through interrogation of environment and environmental records at the Curiosity rover field site in Gale crater. The MSL team has two methods available to collect, process and deliver samples to onboard analytical laboratories, the Chemistry and Mineralogy instrument (CheMin) and the Sample Analysis at Mars (SAM) instrument suite. One approach obtains samples by drilling into a rock, the other uses a scoop to collect loose regolith fines. Scooping was planned to be first method performed on Mars because materials could be readily scooped multiple times and used to remove any remaining, minute terrestrial contaminants from the sample processing system, the Collection and Handling for In-Situ Martian Rock Analysis (CHIMRA). Because of this cleaning effort, the ideal first material to be scooped would consist of fine to very fine sand, like the interior of the Serpent Dune studied by the Mars Exploration Rover (MER) Spirit team in 2004 [1]. The MSL team selected a linear eolian deposit in the lee of a group of cobbles they named Rocknest (Fig. 1) as likely to be similar to Serpent Dune. Following the definitions in Chapter 13 of Bagnold [2], the deposit is termed a sand shadow. The scooping campaign occurred over approximately 6 weeks in October and November 2012. To support these activities, the Mars Hand Lens Imager (MAHLI) acquired images for engineering support/assessment and scientific inquiry.

Edgett, K. S.; Yingst, R. A.; Minitti, M. E.; Goetz, W.; Kah, L. C.; Kennedy, M. R.; Lipkaman, L. J.; Jensen, E. H.; Anderson, R. C.; Beegle, L. W.; Carsten, J. L.; Cooper, B.; Deen, R. G.; Dromart, G.; Eigenbrode, J. L.; Grotzinger, J. P.; Gupta, S.; Hamilton, V. E.; Hardgrove, C. J.; Harker, D. E.; Herkenhoff, K. E.; Herrera, P. N.; Hurowitz, J. A.; Jandura, L.; Ming, D. W.

2013-01-01

191

Capillary damage in the area postrema by venom of the northern black-tailed rattlesnake (Crotalus molossus molossus)  

PubMed Central

The Northern black-tailed rattlesnake (Crotalus molossus molossus) venom is mainly hemotoxic, hemorrhagic, and neurotoxic. Its effects in the central nervous system are unknown and only poorly described for all Viperidae species in general. This is why we are interested in describe the damage induced by C. m. molossus venom in rat brain, particularly in the area postrema capillaries. Four C. m. molossus venom doses were tested (0.02, 0.05, 0.10 and 0.20mg/kg) injected intramuscularly at the lower limb, incubated by 24 hours and the brains were harvested. Area postrema coronal sections were stained with Haematoxylin and Eosin, and examined to observe the venom effect in quantity of capillaries and porphology. Starting from the 0.10mg/kg treatment we observed lysed extravasated erythrocytes and also capillary breakdown, as a consequence of hemorrhages appearance. The number of capillaries decreased significantly in response to the venom dose increment. Hemorrhages could be caused by the metalloproteinase activity on the basal membrane and the apoptosis generated by L-amino acid oxidases. Hemolysis could be caused by phospholipase A2 hemotoxic effect. We conclude that C. m. molossus crude venom produces hemolysis, capillary breakdown, hemorrhages, and the reduction in number of capillaries in the area postrema. PMID:25035793

Melendez-Martinez, David; Macias-Rodriguez, Eduardo; Vargas-Caraveo, Alejandra; Martinez-Martinez, Alejandro; Gatica-Colima, Ana; Plenge-Tellechea, Luis Fernando

2014-01-01

192

Reptile envenomations.  

PubMed

Venomous reptiles are distributed in select habitats in temperate and tropical areas of the world with few geographical exceptions, and have adapted to not only terrestial existence, but to arboreal and aquatic environments as well. Venomous snakes are found in the families Colubridae (fixed and rear fanged snakes), Elapidae (fixed and front fang snakes), Hydrophiidae (sea snakes), Viperidae (Old World vipers) and Crotalidae (pit vipers). Venomous lizards are found in the United States and Mexico, and comprise the family Helodermatidae. Venom delivery systems and venom components show diversity, and greater appreciation of interspecies clinical effect is apparent in modern literature. First aid care for the bitten individual remains controversial, but most authorities now tend to minimize field procedures, especially those endeavors which may potentially damage tissue. The weight of evidence in the area of definitive therapy lies with the use of antivenin, although proponents of primary surgical intervention in crotalid envenomations have followings, particularly in the United States. Recent developments in "purification" of existing antivenins are promising, and attention to species-specific antivenin production, especially to the venoms of the crotalid species of the New World, is encouraged. Due to a growing international traffic in venomous animals for the purposes of research and supply of zoos and private reptile collections, knowledge of resources for assistance in bites of non-indigenous reptiles is a growing consideration. PMID:6381754

Kunkel, D B; Curry, S C; Vance, M V; Ryan, P J

193

[Study on the venoms of the principal venomous snakes from French Guiana and the neutralization].  

PubMed

We studied some biochemical, toxic and immunological characteristics of the venoms of Bothrops atrox, Bothrops brazili and Lachesis muta, Viperidae responsible for most of the bites of venomous snakes in French Guiana. Chromatographic (HPLC) and electrophoretical profiles (SDS-PAGE), lethal, hemorrhagic, defibrinogenating, coagulant, thrombin like, proteolytic, fibrino(geno)lytic and phospholipase activities were studied. In addition, the neutralization of some toxic activities conferred by four antivenins was compared. The chromatographic and electrophoretic profiles were different for the three venoms, showing differences between Bothrops and L. muta venoms. In general, bothropic venoms showed the highest toxic and enzymatic activities, while the venom of L. muta showed the lowest lethal, hemorrhagic and coagulant activities. The enzymes of bothropic venoms responsible for gelatinolytic activity were around 50-90 kDa. All the venoms were able to hydrolyze a and beta chains of the fibrinogen, showing different patterns of degradation. Although all the antivenoms tested were effective to various degrees in neutralizing the venom of B. brazili and B. atrox, neutralization of L. muta venom was significantly better achieved using the antivenom including this venom in its immunogenic mixture. For the neutralization of L. muta venom, homologous or polyvalent antivenoms that include the "bushmaster" venom in their immunogenic mixture should be preferred. PMID:18956820

Estévez, J; Magaña, P; Chippaux, J P; Vidal, N; Mancilla, R; Paniagua, J F; de Roodt, A R

2008-10-01

194

Expression of mRNAs coding for VAP1/crotastatin-like metalloproteases in the venom glands of three South American pit vipers assessed by quantitative real-time PCR.  

PubMed

Snake venom metalloproteases encompass a large family of toxins, with approximately 200 members already catalogued, which exhibit a diversity of structures and biological functions. From this relatively large number, only a dozen examples of apoptosis-inducing metalloproteases, like VAP1 and 2 from the venom of Crotalus atrox, are known. Since most VAP1-like toxins ever characterized were purified from the venom of Viperidae species inhabiting diverse places on earth, we investigate the expression of VAP-like metalloproteases in the venom gland of three representative pit vipers of the Brazilian territory. By molecular cloning and quantitative real-time polymerase chain reaction, using as calibrator gene the Crotalus durissus terrificus homolog of VAP1, named crotastatin, it is reported here that VAP1/crotastatin-like homologues in the venom gland of Bothrops atrox, C. d. cascavella and Lachesis m. rhombeata are expressed at different levels. Hence, batroxstatins, the crotastatin-like precursors from B. atrox, are expressed 87 times more than crotastatin-1, from C. d. cascavella, and 7.5-fold that lachestatins, from L. m. rhombeata. Moreover, in silico structural analysis of amino acid sequences indicates that batroxstatin-2, crotastatins and lachestatin-1 and -2 which share the archetypal motifs and metal- binding sites of VAP1, are subgrouped in a branch that comprises some apoptosis-inducing toxins. PMID:18926840

Tavares, N A C; Correia, J M; Guarnieri, M C; Lima-Filho, J L; Prieto-da-Silva, A R B; Rádis-Baptista, G

2008-12-15

195

Snakebite management in Iran: Devising a protocol  

PubMed Central

Background: Snakebite in Iran has been a health concern. However, management of snakebite is not standardized and varies from center to center. This study is aimed at devising an evidence-based comprehensive protocol for snakebite management in Iran, to reduce unnecessary variations in practice. Materials and Methods: A narrative search in electronic databases was performed. Fifty peer-reviewed articles, guidelines, and textbooks were reviewed and practical details were extracted. Our currently used protocol in the Mashhad Toxicology Center was supplemented with this information. Consequently an improved wide-range protocol was developed. The protocol was then discussed and amended within a focus group comprised of medical toxicologists and internal medicine specialists. The amended version was finally discussed with expert physicians specialized in different areas of medicine, to be optimized by supplementing other specific considerations. Results: During a one-year process, the protocol was finalized. The final version of the protocol, which was designed in six steps, comprised of three components: A schematic algorithm, a severity grading scale, and instructions for supportive and adjunctive treatments. The algorithm pertains to both Viperidae and Elapidae snakebite envenomations and consists of a planned course of action and dosing of antivenom, based on the severity of the envenomation. Conclusion: Snakebite envenomation is a clinical toxicologic emergency, which needs to be treated in a timely and organized manner. Hence, a multi-aspect protocol was designed to improve the clinical outcomes, reduce unnecessary administration of antivenom, and help physicians make more proper clinical judgments. PMID:24778670

Monzavi, Seyed Mostafa; Dadpour, Bita; Afshari, Reza

2014-01-01

196

Molecular Cloning, Characterization, and Chromosome Mapping of Reptilian Estrogen Receptors  

PubMed Central

In many vertebrates, steroid hormones are essential for ovarian differentiation during a critical developmental stage as well as promoting the growth and differentiation of the adult female reproductive system. Although studies have been extensively conducted in mammals and a few fish, amphibians, and bird species, the molecular mechanisms of sex steroid hormone (estrogens) action have been poorly examined in reptiles. Here, we evaluate hormone receptor and ligand interactions in two species of snake, the Okinawa habu (Protobothrops flavoviridis, Viperidae) and the Japanese four-striped rat snake (Elaphe quadrivirgata, Colubridae) after the isolation of cDNAs encoding estrogen receptor ? (ESR1) and estrogen receptor ? (ESR2). Using a transient transfection assay with mammalian cells, the transcriptional activity of reptilian (Okinawa habu, Japanese four-striped rat snake, American alligator, and Florida red-belly freshwater turtle) ESR1 and ESR2 was examined. All ESR proteins displayed estrogen-dependent activation of transcription via an estrogen-response element-containing promoter; however, the responsiveness to various estrogens was different. Further, we determined the chromosomal locations of the snake steroid hormone receptor genes. ESR1 and ESR2 genes were localized to the short and long arms of chromosome 1, respectively, whereas androgen receptor was localized to a pair of microchromosomes in the two snake species examined. These data provide basic tools that allow future studies examining receptor-ligand interactions and steroid endocrinology in snakes and also expands our knowledge of sex steroid hormone receptor evolution. PMID:20926589

Katsu, Yoshinao; Matsubara, Kazumi; Kohno, Satomi; Matsuda, Yoichi; Toriba, Michihisa; Oka, Kaori; Guillette, Louis J.; Ohta, Yasuhiko; Iguchi, Taisen

2010-01-01

197

Scales microstructure of snakes from the Egyptian area.  

PubMed

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. PMID:23106563

Allam, Ahmed A; Abo-Eleneen, Rasha E

2012-11-01

198

Small serum protein-1 changes the susceptibility of an apoptosis-inducing metalloproteinase HV1 to a metalloproteinase inhibitor in habu snake (Trimeresurus flavoviridis)  

PubMed Central

Viperidae snakes containing various venomous proteins also have several anti-toxic proteins in their sera. However, the physiological function of serum protein has been elucidated incompletely. Small serum protein (SSP)-1 is a major component of the SSPs isolated from the serum of a Japanese viper, the habu snake (Trimeresurus flavoviridis). It exists in the blood as a binary complex with habu serum factor (HSF), a snake venom metalloproteinase inhibitor. Affinity chromatography of the venom on an SSP-1-immobilized column identified HV1, an apoptosis-inducing metalloproteinase, as the target protein of SSP-1. Biacore measurements revealed that SSP-1 was bound to HV1 with a dissociation constant of 8.2 × 10?8 M. However, SSP-1 did not inhibit the peptidase activity of HV1. Although HSF alone showed no inhibitory activity or binding affinity to HV1, the SSP-1–HSF binary complex bound to HV1 formed a ternary complex that non-competitively inhibited the peptidase activity of HV1 with a inhibition constant of 5.1 ± 1.3 × 10?9 M. The SSP-1–HSF complex also effectively suppressed the apoptosis of vascular endothelial cells and caspase 3 activation induced by HV1. Thus, SSP-1 is a unique protein that non-covalently attaches to HV1 and changes its susceptibility to HSF. PMID:23100271

Shioi, Narumi; Ogawa, Eiki; Mizukami, Yuki; Abe, Shuhei; Hayashi, Rieko; Terada, Shigeyuki

2013-01-01

199

Hunter-gatherers and other primates as prey, predators, and competitors of snakes.  

PubMed

Relationships between primates and snakes are of widespread interest from anthropological, psychological, and evolutionary perspectives, but surprisingly, little is known about the dangers that serpents have posed to people with prehistoric lifestyles and nonhuman primates. Here, we report ethnographic observations of 120 Philippine Agta Negritos when they were still preliterate hunter-gatherers, among whom 26% of adult males had survived predation attempts by reticulated pythons. Six fatal attacks occurred between 1934 and 1973. Agta ate pythons as well as deer, wild pigs, and monkeys, which are also eaten by pythons, and therefore, the two species were reciprocally prey, predators, and potential competitors. Natural history data document snake predation on tree shrews and 26 species of nonhuman primates as well as many species of primates approaching, mobbing, killing, and sometimes eating snakes. These findings, interpreted within the context of snake and primate phylogenies, corroborate the hypothesis that complex ecological interactions have long characterized our shared evolutionary history. PMID:22160702

Headland, Thomas N; Greene, Harry W

2011-12-27

200

e-MERLIN data reduction pipeline  

NASA Astrophysics Data System (ADS)

Written in Python and utilizing ParselTongue (ascl:1208.020) to interface with AIPS (ascl:9911.003), the e-MERLIN data reduction pipeline processes, calibrates and images data from the UK's radio interferometric array (Multi-Element Remote-Linked Interferometer Network). Driven by a plain text input file, the pipeline is modular and can be run in stages. The software includes options to load raw data, average in time and/or frequency, flag known sources of interference, flag more comprehensively with SERPent (ascl:1312.001), carry out some or all of the calibration procedures (including self-calibration), and image in either normal or wide-field mode. It also optionally produces a number of useful diagnostic plots at various stages so data quality can be assessed.

Argo, Megan

2014-07-01

201

Snake Robots.com  

NSDL National Science Digital Library

One of the latest developments in robotics is flexible, snake-like machines that could be used for such activities as Martian landscape exploration because they are highly flexible, adaptable, and maneuverable into tight spaces and over relatively large obstacles. Snake Robots.com comes from robotics engineer Gavin Miller who developed his own "snakes" with inspiration from his work on physically-based computer animation at Alias Research, Inc. and Apple Computer, Inc. (Note: this private site is not affiliated with those corporations.) Visitors to Miller's site can see color videos, with audio, of his incredibly life-like serpents (.mpeg). Links to other snake robot sites are provided along with information about upcoming museum exhibitions and articles.

202

Helminth fauna of a Japanese golden eagle, Aquila chrysaetos japonica.  

PubMed

A Japanese golden eagle, Aquila chrysaetos japonica, was found dead in Nagano Prefecture PB 399-8200, Japan, and subjected to necropsy. The necropsy revealed that the entire length of the intestine was filled with several masses of intestinal parasites. The recovered helminths were identified as one digenean trematode species, Neodiplostomum reflexum; two species of nematodes, Synhimantus sp. and larvae of Porrocaecum sp.; and a single species of Acanthocephala, Centrorhynchus sp. Digenea and acanthocephalans were found in massive numbers, obliterating the intestinal lumen, which suggests that the bird died as a result of the parasitic intestinal obstruction. The same type of helminths as those observed in this case was previously recorded in crested serpent eagles (Spilornis cheela perplexus) in Japan, but the present study emphasizes the presence of the four species in the Japanese golden eagle as a new host record. To the authors' knowledge, this is the first report of N. reflexum in Japan. PMID:23272374

El-Dakhly, Khaled; El-Nahass, El-Shaymaa; Sudo, Akiko; Uchida, Tadayoshi; Kakogawa, Masayoshi; Hirata, Akihiro; Sakai, Hiroki; Yanai, Tokuma

2012-12-01

203

Presence of a radioactive gas in archaeological excavations, determination and mitigation.  

PubMed

During recent archaeological discovery and excavation of a tunnel build approximately 2000 years ago by the Teotihuacans under the feathered serpent temple, in Mexico, abnormal radon concentrations up to 700 Bq m(-3) were measured at several excavation stages. The tunnel is at 15m below the earth surface with a vertical rectangular entrance of 4×4 m(2), a semi cylindrical shape of 3m in diameter, with a probable length of 100 m. This study supports the assumption that at the opening of the tunnel radon concentration was around 5500 Bq m(-3); however, although natural convection in the tunnel atmosphere naturally pups radon out, it build up to a maximum concentration of 2000 Bq m(-3). This paper presents the identification of the radon problem in this archaeological site, dose determination, and the mitigation actions that reduced the radon concentration down to 40 Bq m(-3) that ensure a negligible radon risk for archaeologist. PMID:23938077

Balcázar, M; Gómez, S; Peña, P; Zavala Arredondo, J; Gazzola, J; Villamares, A

2014-01-01

204

Boron concentration in water, sediment and different organisms around large borate deposits of Turkey.  

PubMed

Boron is an essential nutrient for plants and an essential element for many organisms, but can be toxic to aquatic and terrestrial organisms above certain concentrations. The aim of this research was to determine boron concentrations in water, sediment and biotic samples (Gammaridae spp.-Crustacea, Helix sp.-Gastropoda, Donax sp.-Bivalvia, Helobdella sp.-Hirudinae, Ephemeroptera nymph, Chrinomidae larvae, Tipulidae larvae-Insecta, Rana sp.-Amphibia, Natrix sp.-Serpentes, fish sample Leiscus cephalus (Linnaeus, 1758) and leaves of Salix sp.-Salicacea from Seydi Stream (Kirka-Eski?ehir). Our results have shown that boron concentrations of the Seydi Stream water is higher than the Turkish Environmental Guidelines standard (>1 mg L(-1)) and in Europe (mean values typically below 0.6 mg L(-1)). PMID:20352187

Emiro?lu, Ozgür; Ciçek, Arzu; Arslan, Naime; Aksan, Serdar; Rüzgar, Melih

2010-04-01

205

Teotihuacan and its influence in Mesoamerica. Archaeomagnetic studies  

NASA Astrophysics Data System (ADS)

Teotihuacan located at the north of the Basin of Mexico was one of the most important metropolises of Mesoamerica between AD 300-500. The chronological information of the city and its neighborhoods is very important to understand its evolution. We present the results of the sampling at the Feathered Serpent Temple and E complex at La Ciudadela, a zone at the south area of the Pyramids of the Sun and the Moon. These results correspond with a stratigraphic sequence between the 50 BC to AD 500. Two ritual events related with the beginning and the end of the Xolalpan stage (AD325-AD545) were archaeomagnetic dated, events that had been observed too at Teopancazco, the neighborhood of the taylors located at the SE of the city, denoting the importance of them. The beginning of Xolalpan stage is related with the exile of a group of teotihuacan warriors that arrived to Tikal.

Terán, A.; Soler-Arechalde, A. M.

2013-05-01

206

Floridas Miami Tequesta Indian Site, Its Calusa Indian Locations, the Matacumbe Keys, and Orlandos Wikiwa Springs Generate Environmentally Significant EMFs.  

NASA Astrophysics Data System (ADS)

Florida purchased the Tequesta ([Langue] doc Christ Spirit-signal) Indian site along the Miami River site that vigorously pulsates with even minor rainstorms entering or leaving the area. Although there is a laughable chimera of a fountain of youth associated with Ponce de Leons discovery of the Florida peninsula in about AD 1513, the Calusa (Royal Christ Jesus Spirit-signal) Indian Nation has an associated significance with EMF signals they possibly monitored throughout their area of activity. Our efforts have also led to the investigation of cultural and other influences implied by the Matacumbe Keys that indicate a shared commonality of awareness with Native Americans of the northeast such as Metacomet, or regions like Maines Grand Lake Matagamon and its associated electromagnetic Spirit Signal. Wikiwa Springs near Orlando shares much with Massachusetts (adherent of serpent Jesus Christ Spirit-signal) Natick, and New Hampshires Naticook Island. These are the locales of environmentally sensitive instrumentation.

Mac Dougall, Jean S.; Mc Leod, Roger D.; Mc Leod, David M.

2003-10-01

207

Origins of the ancient constellations: I. The Mesopotamian traditions  

NASA Astrophysics Data System (ADS)

In the sky-map of ancient Babylon, constellations had two different roles, and thus developed into two overlapping traditions. One set of constellations represented the gods and their symbols; the other set represented rustic activities and provided a farming calendar. Many constellations were shared by the two traditions, but in some regions of sky there were alternative divine and rustic figures. These figures developed in stages from ~3200 BC to ~500 BC. Of the divine set, the most important (although the last to be finalised) were the twelve zodiacal signs, plus several associated animals (the serpent, crow, eagle, and fish), which were all transmitted to the classical Greek sky-map that we still use today. Conversely, the rustic constellations of workers and tools and animals were not transmitted to the West. However, a few of them may have survived in Bedouin Arab sky-maps of the first millennium AD.

Rogers, J. H.

1998-02-01

208

Molecular cloning and expression of catrocollastatin, a snake-venom protein from Crotalus atrox (western diamondback rattlesnake) which inhibits platelet adhesion to collagen.  

PubMed Central

A 50 kDa protein that inhibits platelet adhesion to collagen has been isolated from snake venom of Crotalus atrox (western diamondback rattlesnake) and has been named 'catrocollastatin'. The cDNA cloning of catrocollastatin has been accomplished. A full-length cDNA of 2310 bp with an open reading frame between nucleotides 51 and 1880 was obtained. The deduced amino acid sequence consists of 609 amino acids. The cDNA-predicted amino acid sequence is highly similar to that of haemorrhagic metalloproteinase jararhagin from Bothrops jararaca venom, HR1B from Trimeresurus flavoviridis, Ht-e from C. atrox and trigramin from T. gramineus. Like jararhagin and HR1B, catrocollastatin is a multidomain molecule composed of an N-terminal domain, a metalloproteinase domain, a disintegrin-like domain and a cysteine-rich C-terminal domain. In the disintegrin-like domain, the frequently seen RGD (Arg-Gly-Asp) sequence is replaced by SECD (Ser-Glu-Cys-Asp). This cDNA was expressed in Spodoptera frugiperda (fall armyworm) (Sf9) insect cells using a baculovirus expression system. Like native catrocollastatin, the expressed protein is capable of selectively blocking collagen-induced platelet aggregation. This is the first full-length clone of a high-molecular-mass haemorrhagin to be expressed. Images Figure 1 Figure 4 PMID:7733877

Zhou, Q; Smith, J B; Grossman, M H

1995-01-01

209

Development of an ELISA to assess the potency of horse therapeutic polyvalent antibothropic antivenom.  

PubMed

The objective of this study was the search for a suitable venom antigen to be used in an in vitro alternative immunoassay, to the standard antivenom neutralization assay using mice. Bothrops jararaca venom was fractionated in DEAE-Sephacel columns and the fractions were tested for a correlation between antibody capture enzyme linked immunosorbent assay (ELISA) absorbance values and the 'in vivo' antivenom potency. Individual antivenoms from 14 horses and 15 separate FUNED polyspecific Bothrops ampouled antivenoms (final product) were used. Fractions showing the higher correlations were further chromatographed in a Sephadex G-75 column and again tested for the correlation. Two fractions with haemorrhagic activity displayed a correlation of r = 0.77 and r = 0.8 against the individual horse antivenom sera and of r = 0.79 and r = 0.8 for the ampouled antivenom. For all results p < 0.001. Two other fractions with phospholipase A2 activity showed a correlation of r = 0.66 (p < 0.01) and r = 0.56 (p < 0.03) against the individual horse antivenom sera. Electrophoresis results show a similar composition for both antigens with haemorrhagic activity. Results indicate that the fractions purified would be suitable for the desired objective of this study. PMID:9723835

Heneine, L G; Carvalho, A D; Barbosa, C F; Arávjo dos Santos, M R

1998-10-01

210

Interaction of viper venom serine peptidases with thrombin receptors on human platelets.  

PubMed

The serine peptidases, thrombocytin and PA-BJ, isolated from the venom of Bothrops atrox and Bothrops jararaca, respectively, induce platelet aggregation and granule secretion without clotting fibrinogen. The specific platelet aggregation activity of each enzyme was about 15 times lower than that of thrombin. This activity was blocked by monoclonal antibodies recognizing protease activated receptor 1 (PAR1) and by heparin, but not by hirudin nor thrombomodulin. Both enzymes induced calcium mobilization in platelets and desensitized platelets to the action of thrombin and the SFLLRN peptide. We compared the effect of thrombin, PA-BJ, and thrombocytin on the degradation of the soluble N-terminal domain of the PAR1 receptor. The major cleavage site by thrombin and both viper enzymes was Arg41-Ser42. In addition, a rapid cleavage of the peptide bond at Arg46-Asn47 by the viper enzymes was observed, resulting in the inactivation of the tethered ligand. PA-BJ and thrombocytin both cleaved at 41-42 and 46-47 peptide bonds, and fragment 42-103 disappeared rapidly. Both viper enzymes caused calcium mobilization in fibroblasts transfected with PAR4 and desensitized these cells to the thrombin action. In conclusion, both PAR1 and PAR4 mediate the effect of viper venom serine peptidases on platelets. PMID:10908720

Santos, B F; Serrano, S M; Kuliopulos, A; Niewiarowski, S

2000-07-21

211

Effects of Schizolobium parahyba Extract on Experimental Bothrops Venom-Induced Acute Kidney Injury  

PubMed Central

Background Venom-induced acute kidney injury (AKI) is a frequent complication of Bothrops snakebite with relevant morbidity and mortality. The aim of this study was to assess the effects of Schizolobium parahyba (SP) extract, a natural medicine with presumed anti-Bothrops venom effects, in an experimental model of Bothrops jararaca venom (BV)-induced AKI. Methodology Groups of 8 to 10 rats received infusions of 0.9% saline (control, C), SP 2 mg/kg, BV 0.25 mg/kg and BV immediately followed by SP (treatment, T) in the doses already described. After the respective infusions, animals were assessed for their glomerular filtration rate (GFR, inulin clearance), renal blood flow (RBF, Doppler), blood pressure (BP, intra-arterial transducer), renal vascular resistance (RVR), urinary osmolality (UO, freezing point), urinary neutrophil gelatinase-associated lipocalin (NGAL, enzyme-linked immunosorbent assay [ELISA]), lactate dehydrogenase (LDH, kinetic method), hematocrit (Hct, microhematocrit), fibrinogen (Fi, Klauss modified) and blinded renal histology (acute tubular necrosis score). Principal Findings BV caused significant decreases in GFR, RBF, UO, HcT and Fi; significant increases in RVR, NGAL and LDH; and acute tubular necrosis. SP did not prevent these changes; instead, it caused a significant decrease in GFR when used alone. Conclusion SP administered simultaneously with BV, in an approximate 10?1 concentration, did not prevent BV-induced AKI, hemolysis and fibrinogen consumption. SP used alone caused a decrease in GFR. PMID:24551041

Martines, Monique Silva; Mendes, Mirian M.; Shimizu, Maria H. M.; Melo Rodrigues, Veridiana; de Castro, Isac; Filho, Sebastiao R. Ferreira; Malheiros, Denise M. A. C.; Yu, Luis; Burdmann, Emmanuel A.

2014-01-01

212

Transcriptome analysis of the Amazonian viper Bothrops atrox venom gland using expressed sequence tags (ESTs).  

PubMed

Bothrops atrox is a highly dangerous pit viper in the Brazilian Amazon region. We produced a global catalogue of gene transcripts to identify the main toxin and other protein families present in the B. atrox venom gland. We prepared a directional cDNA library, from which a set of 610 high quality expressed sequence tags (ESTs) were generated by bioinformatics processing. Our data indicated a predominance of transcripts encoding mainly metalloproteinases (59% of the toxins). The expression pattern of the B. atrox venom was similar to Bothrops insularis, Bothrops jararaca and Bothrops jararacussu in terms of toxin type, although some differences were observed. B. atrox showed a higher amount of the PIII class of metalloproteinases which correlates well with the observed intense hemorrhagic action of its toxin. Also, the PLA2 content was the second highest in this sample compared to the other three Bothrops transcriptomes. To our knowledge, this work is the first transcriptome analysis of an Amazonian rain forest pit viper and it will contribute to the body of knowledge regarding the gene diversity of the venom gland of members of the Bothrops genus. Moreover, our results can be used for future studies with other snake species from the Amazon region to investigate differences in gene patterns or phylogenetic relationships. PMID:19708221

Neiva, Márcia; Arraes, Fabricio B M; de Souza, Jonso Vieira; Rádis-Baptista, Gandhi; Prieto da Silva, Alvaro R B; Walter, Maria Emilia M T; Brigido, Marcelo de Macedo; Yamane, Tetsuo; López-Lozano, Jorge Luiz; Astolfi-Filho, Spartaco

2009-03-15

213

Characterization and cDNA cloning of aminopeptidase A from the venom of Gloydius blomhoffi brevicaudus.  

PubMed

The aminopeptidase activities of snake venoms from Gloydius blomhoffi brevicaudus, Gloydius halys blomhoffii, Trimeresurus flavoviridis, Bothrops jararaca and Crotalus atrox were investigated. Aminopeptidase A (APA), aminopeptidase B and aminopeptidase N activities were present in all snake venoms. The strongest APA activity was found in venom from G. blomhoffi brevicaudus. The susceptibility to metallopeptidase inhibitors and the pH optimum of the partially purified enzyme from G. blomhoffi brevicaudus venom were similar to those of known APAs from mammals. A G. blomhoffi brevicaudus venom gland cDNA library was screened to isolate cDNA clones using probes based on highly conserved amino acid sequences in known APAs. Molecular cloning of APA from G. blomhoffi brevicaudus venom predicted that it was a type II integral membrane protein containing 958 amino acid residues with 17 potential N-linked glycosylation sites. It possessed a His-Glu-Xaa-Xaa-His-(Xaa)(18)-Glu zinc binding motif that allowed the classification of this protein as a member of the M1 family of zinc-metallopeptidases, or gluzincins. The deduced amino acid sequence shows approximately 60% sequence identity to mammalian APA sequences. This is the first study to report the primary structure of APA from a reptile. PMID:17383704

Ogawa, Yuko; Murayama, Nobuhiro; Fujita, Yoshiaki; Yanoshita, Ryohei

2007-06-15

214

Preclinical assessment of the neutralizing capacity of antivenoms produced in six Latin American countries against medically-relevant Bothrops snake venoms.  

PubMed

Species of the genus Bothrops induce the vast majority of snakebite envenomings in Latin America. A preclinical study was performed in the context of a regional network of public laboratories involved in the production, quality control and development of antivenoms in Latin America. The ability of seven polyspecific antivenoms, produced in Argentina, Brazil, Peru, Bolivia, Colombia and Costa Rica, to neutralize lethal, hemorrhagic, coagulant, defibrinogenating and myotoxic activities of the venoms of Bothrops neuwiedi (diporus) (Argentina), Bothrops jararaca (Brazil), B. neuwiedi (mattogrossensis) (Bolivia), Bothrops atrox (Peru and Colombia) and Bothrops asper (Costa Rica) was assessed using standard laboratory tests. Despite differences in the venom mixtures used in the immunization of animals for the production of these antivenoms, a pattern of extensive cross-neutralization was observed between these antivenoms and all the venoms tested, with quantitative differences in the values of effective doses. This study reveals the capacity of these antivenoms to neutralize, in preclinical tests, homologous and heterologous Bothrops venoms in Central and South America, and also highlight quantitative differences in the values of Median Effective Doses (ED50s) between the various antivenoms. PMID:20621114

Segura, A; Castillo, M C; Núñez, V; Yarlequé, A; Gonçalves, L R C; Villalta, M; Bonilla, C; Herrera, M; Vargas, M; Fernández, M; Yano, M Y; Araújo, H P; Boller, M A A; León, P; Tintaya, B; Sano-Martins, I S; Gómez, A; Fernández, G P; Geoghegan, P; Higashi, H G; León, G; Gutiérrez, J M

2010-11-01

215

A survey of hemoparasite infections in free-ranging mammals and reptiles in French Guiana.  

PubMed

Blood smears of 1,353 free-ranging mammals (35 species) and 112 reptiles (31 species) from French Guiana were examined for hemoparasites. Parasites from 3 major groups were recorded: Apicomplexa (including hemogregarines, piroplasms, and Plasmodium spp.), Trypanosomatidae, and Filaroidea. Fifty percent of the individuals (86% of the species) were infected by parasites from at least 1 group. Hemogregarines, identified as Hepatozoon sp., infected numerous snakes with high prevalences (30-100%); infection is reported for the first time in 5 host genera of snakes: Clelia, Oxybelis, Pseustes, Rhinobotryum, and Bothriopsis. Infections were also observed in 4 marsupial species and 1 rodent. Hepatozoon spp. recorded in Didelphis albiventris (Marsupialia) and Coendou prehensilis (Rodentia) may be new species. Plasmodium sp. were observed in 2 snake species, Dipsas indica (Colubridae) and Bothrops atrox (Viperidae). Plasmodium brasilianum was recorded in all 5 primate species examined. Piroplasms were observed in all mammal orders except primates. Large terrestrial rodents were the main hosts of members of the Babesidae; 42% of Myoprocta acouchy, 36% of Dasyprocta agouti, and 44% of Agouti paca were infected. Trypanosomes were common in mammals and were recorded in 70% of the examined genera. Trypanosoma cruzi-like infections were reported in 21 mammal species, including sloths, rodents, carnivores, and primates. Microfilariae were also widespread, with higher prevalences in sloths, anteaters, and porcupines (>40% of the individuals infected) and in tamarins (95% infected). This survey highlights some potential anthropozoonotic risks due to the recent further evidence of Plasmodium brasilianum and P. malariae as a single species and to the increased diversity of hosts for Trypanosoma cruzi. PMID:11128476

de Thoisy, B; Michel, J C; Vogel, I; Vié, J C

2000-10-01

216

Isolation and characterization of two disintegrins inhibiting ADP-induced human platelet aggregation from the venom of Crotalus scutulatus scutulatus (Mohave Rattlesnake)  

SciTech Connect

Disintegrins and disintegrin-like proteins are molecules found in the venom of four snake families (Atractaspididae, Elapidae, Viperidae, and Colubridae). The disintegrins are nonenzymatic proteins that inhibit cell-cell interactions, cell-matrix interactions, and signal transduction, and may have potential in the treatment of strokes, heart attacks, cancers, and osteoporosis. Prior to 1983, the venom of Crotalus scutulatus scutulatus (Mohave Rattlesnake) was known to be only neurotoxic; however, now there is evidence that these snakes can contain venom with: (1) neurotoxins; (2) hemorrhagins; and (3) both neurotoxins and hemorrhagins. In this study, two disintegrins, mojastin 1 and mojastin 2, from the venom of a Mohave rattlesnake collected in central Arizona (Pinal County), were isolated and characterized. The disintegrins in these venoms were identified by mass-analyzed laser desorption ionization/time-of-flight/time-of-flight (MALDI/TOF/TOF) mass spectrometry as having masses of 7.436 and 7.636 kDa. Their amino acid sequences are similar to crotratroxin, a disintegrin isolated from the venom of the western diamondback rattlesnake (C. atrox). The amino acid sequence of mojastin 1 was identical to the amino acid sequence of a disintegrin isolated from the venom of the Timber rattlesnake (C. horridus). The disintegrins from the Mohave rattlesnake venom were able to inhibit ADP-induced platelet aggregation in whole human blood both having IC{sub 5}s of 13.8 nM, but were not effective in inhibiting the binding of human urinary bladder carcinoma cells (T24) to fibronectin.

Sanchez, Elda E. [Natural Toxins Research Center, College of Arts and Science, 920 University Blvd. MSC 158, Texas A and M University-Kingsville, MSC 158, Kingsville, TX 78363 (United States); Galan, Jacob A. [Natural Toxins Research Center, College of Arts and Science, 920 University Blvd. MSC 158, Texas A and M University-Kingsville, MSC 158, Kingsville, TX 78363 (United States); Russell, William K. [Laboratory for Biological Mass Spectrometry, Department of Chemistry, PO Box 30012, Texas A and M University, College Station, TX 77842-3013 (United States); Soto, Julio G. [Department of Biological Sciences, One Washington Square Duncan Hall, San Jose State University, San Jose, CA 95192-0100 (United States); Russell, David H. [Laboratory for Biological Mass Spectrometry, Department of Chemistry, PO Box 30012, Texas A and M University, College Station, TX 77842-3013 (United States); Perez, John C. [Natural Toxins Research Center, College of Arts and Science, 920 University Blvd. MSC 158, Texas A and M University-Kingsville, MSC 158, Kingsville, TX 78363 (United States)]. E-mail: kfjcp00@tamuk.edu

2006-04-01

217

Stable isotope tracer reveals that viviparous snakes transport amino acids to offspring during gestation.  

PubMed

Viviparity and placentation have evolved from oviparity over 100 times in squamate reptiles (lizards and snakes). The independent origins of placentation have resulted in a variety of placental morphologies in different taxa, ranging from simple apposition of fetal and maternal tissues to endotheliochorial implantation that is homoplasious with mammalian placentation. Because the eggs of oviparous squamates transport gases and water from the environment and calcium from the eggshell, the placentae of viviparous squamates are thought to have initially evolved to accomplish these functions from within the maternal oviduct. Species with complex placentae have also been shown to rely substantially, or even primarily, on placental transport of organic nutrients for embryonic nutrition. However, it is unclear whether species with only simple placentae are also capable of transporting organic nutrients to offspring. Among viviparous squamates, all of the snakes that have been studied thus far have been shown to have simple placentae. However, most studies of snake placentation are limited to a single lineage, the North American Natricinae. We tested the abilities of four species of viviparous snakes - Agkistrodon contortrix (Viperidae), Boa constrictor (Boidae), Nerodia sipedon (Colubridae: Natricinae) and Thamnophis sirtalis (Colubridae: Natricinae) - to transport diet-derived amino acids to offspring during gestation. We fed [(15)N]leucine to pregnant snakes, and compared offspring (15)N content with that of unlabeled controls. Labeled females allocated significantly more (15)N to offspring than did controls, but (15)N allocation did not differ among species. Our results indicate that viviparous snakes are capable of transporting diet-derived amino acids to their offspring during gestation, possibly via placentation. PMID:22323198

Van Dyke, James U; Beaupre, Steven J

2012-03-01

218

Purification, characterization and cDNA cloning of a phospholipase A2 inhibitor from the serum of the non-venomous snake Elaphe quadrivirgata.  

PubMed Central

The serum of a non-venomous striated snake, Elaphe quadrivirgata, was found to contain phospholipase A2 (PLA2) inhibitory proteins (PLIs). One of these inhibitors was purified by Sephadex G-200 gel filtration, Q-Sepharose FF ion-exchange chromatography and Butyl Sepharose 4FF hydrophobic chromatography. The purified PLI inhibited the enzymic activities of all PLA2 groups, including Elapidae venom (group-I), Viperidae venom (group-II) and honeybee PLA2s (group-III). The inhibitor was a 130 kDa glycoprotein consisting of two distinct subunits, A and B, of 30 and 29 kDa respectively; each of which was glycosylated with N-linked oligosaccharide chains. The cDNAs encoding the respective inhibitor subunits were isolated from a liver cDNA library by the use of probes, prepared by PCR, based on the partially determined amino-acid sequences of the corresponding subunits. The respective nucleotide sequences encoded 19-amino-acid-residue signal sequences, followed by 183- and 181-residue protein sequences for the A and B subunits respectively. The amino-acid sequences revealed that the E. quadrivirgata inhibitor corresponded to PLIgamma, one of three kinds of inhibitors purified from venomous snakes. The existence of PLIgamma in the serum of this non-venomous snake suggested that, besides having a protective role against the venom PLA2s of other venomous snakes, PLIgamma has other important physiological functions in regulating local PLA2 activities; and thus it raises the possibility that PLIgamma occurs in other animals, including mammals. PMID:10377258

Okumura, K; Masui, K; Inoue, S; Ikeda, K; Hayashi, K

1999-01-01

219

Structural and Functional Studies of a Bothropic Myotoxin Complexed to Rosmarinic Acid: New Insights into Lys49-PLA2 Inhibition  

PubMed Central

Snakebite envenoming is an important public health problem in many tropical and subtropical countries, and is considered a neglected tropical disease by the World Health Organization. Most severe cases are inflicted by species of the families Elapidae and Viperidae, and lead to a number of systemic and local effects in the victim. One of the main problems regarding viperidic accidents is prominent local tissue damage whose pathogenesis is complex and involves the combined actions of a variety of venom components. Phospholipases A2 (PLA2s) are the most abundant muscle-damaging components of these venoms. Herein, we report functional and structural studies of PrTX-I, a Lys49-PLA2 from Bothops pirajai snake venom, and the influence of rosmarinic acid (RA) upon this toxin's activities. RA is a known active component of some plant extracts and has been reported as presenting anti-myotoxic properties related to bothopic envenomation. The myotoxic activity of Lys49-PLA2s is well established in the literature and although no in vivo neurotoxicity has been observed among these toxins, in vitro neuromuscular blockade has been reported for some of these proteins. Our in vitro studies show that RA drastically reduces both the muscle damage and the neuromuscular blockade exerted by PrTX-I on mice neuromuscular preparations (by ?80% and ?90%, respectively). These results support the hypothesis that the two effects are closely related and lead us to suggest that they are consequences of the muscle membrane-destabilizing activity of the Lys49-PLA2. Although the C-terminal region of these proteins has been reported to comprise the myotoxic site, we demonstrate by X-ray crystallographic studies that RA interacts with PrTX-I in a different region. Consequently, a new mode of Lys49-PLA2 inhibition is proposed. Comparison of our results with others in the literature suggests possible new ways to inhibit bothropic snake venom myotoxins and improve serum therapy. PMID:22205953

dos Santos, Juliana I.; Cardoso, Fabio F.; Soares, Andreimar M.; dal Pai Silva, Maeli; Gallacci, Marcia; Fontes, Marcos R. M.

2011-01-01

220

Ten years of snakebites in Iran.  

PubMed

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. PMID:25193748

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

2014-11-01

221

Structure of saxthrombin, a thrombin-like enzyme from Gloydius saxatilis.  

PubMed

Snake-venom thrombin-like enzymes (SVTLEs) are serine proteases that are widely distributed in snakes from the Crotalinae subfamily of the Viperidae. In contrast to other snake-venom serine proteases, they have a biochemical activity similar to that of thrombin and play an important role in the process of blood coagulation. However, SVTLEs cannot activate factor VIII, which is essential in blood-clot stabilization. Consequently, blood clots produced by SVTLEs are not stable and are cleared rapidly. This characteristic makes SVTLEs attractive as potential candidates for antithrombotic therapy. Saxthrombin, an SVTLE from Gloydius saxatilis, was purified and crystallized to obtain a high-quality crystal, from which data were acquired to 1.43?Å resolution. Preliminary X-ray diffraction analysis showed that the crystal belonged to space group C2, with unit-cell parameters a = 94.2, b = 52.2, c = 50.1?Å, ? = 96.7°. The crystal structure was determined by molecular replacement and the final R factor was 18.69%; the R(free) was 20.01%. This is the first report of a crystal structure of an SVTLE. Saxthrombin belongs to the typical ?/?-hydrolase fold of serine proteases. Its structure was compared with those of thrombin and other snake-venom serine proteases. The observed differences in the amino-acid composition of the loops surrounding the active site appear to contribute to different surface-charge distributions and thus alter the shape of the active-site cleft, which may explain the differences in substrate affinity. PMID:21821882

Huang, Kai; Zhao, Wei; Gao, Yongxiang; Wei, Wenqing; Teng, Maikun; Niu, Liwen

2011-08-01

222

A new tyrosine-specific chymotrypsin-like and angiotensin-degrading serine proteinase from Vipera lebetina snake venom.  

PubMed

Vipera lebetina venom contains different metallo- and serine proteinases that affect coagulation and fibrin(ogen)olysis. A novel serine proteinase from V. Lebetina venom having ChymoTrypsin Like Proteolytic activity (VLCTLP) was purified to homogeneity from the venom using Sephadex G-100sf, DEAE-cellulose, heparin-agarose and FPLC on Superdex 75 chromatographies. VLCTLP is a glycosylated serine proteinase with a molecular mass of 41926 Da. It reacts with N-acetyl-L-tyrosine ethyl ester (ATEE) but not with Suc-Ala-Ala-Pro-Phe-pNA or Suc-Ala-Ala-Pro-Leu-pNA. The complete amino acid sequence of the VLCTLP is deduced from the nucleotide sequence of the cDNA encoding this protein. The full-length cDNA sequence of the VLCTLP encodes open reading frame of 257 amino acid residues that includes a putative signal peptide of 18 amino acids, a proposed activation peptide of six amino acid residues and serine proteinase of 233 amino acid residues. VLCTLP belongs to the S1 (chymotrypsin) subfamily of proteases. The multiple alignment of its deduced amino acid sequence showed structural similarity with other serine proteases from snake venoms. The protease weakly hydrolyses azocasein, A?-chain and more slowly B?-chain of fibrinogen. VLCTLP does not cleave fibrin and has no gelatinolytic activity. Specificity studies against peptide substrates (angiotensin I and II, oxidized insulin B-chain, glucagon, fibrinogen fragments etc.) showed that VLCTLP catalysed the cleavage of peptide bonds after tyrosine residues. VLCTLP is the only purified and characterized serine proteinase from snake venoms that catalyses ATEE hydrolysis. We detected ATEE-hydrolysing activities also in 9 different Viperidae and Crotalidae venoms. PMID:20950666

Siigur, Ene; Tõnismägi, Külli; Trummal, Katrin; Samel, Mari; Vija, Heiki; Aaspõllu, Anu; Rönnholm, Gunilla; Subbi, Juhan; Kalkkinen, Nisse; Siigur, Jüri

2011-02-01

223

Molecular Evolution of Vertebrate Neurotrophins: Co-Option of the Highly Conserved Nerve Growth Factor Gene into the Advanced Snake Venom Arsenalf  

PubMed Central

Neurotrophins are a diverse class of structurally related proteins, essential for neuronal development, survival, plasticity and regeneration. They are characterized by major family members, such as the nerve growth factors (NGF), brain-derived neurotrophic factors (BDNF) and neurotrophin-3 (NT-3), which have been demonstrated here to lack coding sequence variations and follow the regime of negative selection, highlighting their extremely important conserved role in vertebrate homeostasis. However, in stark contrast, venom NGF secreted as part of the chemical arsenal of the venomous advanced snake family Elapidae (and to a lesser extent Viperidae) have characteristics consistent with the typical accelerated molecular evolution of venom components. This includes a rapid rate of diversification under the significant influence of positive-selection, with the majority of positively-selected sites found in the secreted ?-polypeptide chain (74%) and on the molecular surface of the protein (92%), while the core structural and functional residues remain highly constrained. Such focal mutagenesis generates active residues on the toxin molecular surface, which are capable of interacting with novel biological targets in prey to induce a myriad of pharmacological effects. We propose that caenophidian NGFs could participate in prey-envenoming by causing a massive release of chemical mediators from mast cells to mount inflammatory reactions and increase vascular permeability, thereby aiding the spread of other toxins and/or by acting as proapoptotic factors. Despite their presence in reptilian venom having been known for over 60 years, this is the first evidence that venom-secreted NGF follows the molecular evolutionary pattern of other venom components, and thus likely participates in prey-envenomation. PMID:24312363

Sunagar, Kartik; Fry, Bryan Grieg; Jackson, Timothy N. W.; Casewell, Nicholas R.; Undheim, Eivind A. B.; Vidal, Nicolas; Ali, Syed A.; King, Glenn F.; Vasudevan, Karthikeyan; Vasconcelos, Vitor; Antunes, Agostinho

2013-01-01

224

A novel family of RGD-containing disintegrin (Tablysin-15) from the salivary gland of the horsefly Tabanus yao targets integrins ?IIb?3 and ?V?3 and inhibits platelet aggregation and angiogenesis  

PubMed Central

A novel family of RGD-containing molecule (Tablysin-15) has been molecularly characterized from the salivary gland of the hematophagous horsefly Tabanus yao. Tablysin-15 does not share primary sequence homology to any disintegrin discovered so far, and displays an RGD motif in the N-terminus of the molecule. It is also distinct from disintegrins from Viperidae since its mature form is not released from a metalloproteinase precursor. Tablysin-15 exhibits high affinity for platelet ?IIb?3 and endothelial cell ?v?3 integrins, but not for ?5?1 or ?2?1. Accordingly, it blocks endothelial cell adhesion to vitronectin (IC50 ~ 1 nM) and marginally to fibronectin (IC50 ~ 1 µM), but not to collagen. It also inhibits FGF-induced endothelial cell proliferation, and attenuates tube formation in vitro. In platelets, Tablysin-15 inhibits aggregation induced by collagen, ADP and convulxin, and prevents static platelet adhesion to immobilized fibrinogen. In addition, solid-phase assays and flow cytometry demonstrates that ?IIb?3 binds to Tablysin-15. Moreover, immobilized Tablysin-15 supports platelet adhesion by a mechanism which was blocked by anti-integrin ?IIb?3 monoclonal antibody (e.g. abciximab) or by EDTA. Furthermore, Tablysin-15 dose-dependently attenuates thrombus formation to collagen under flow, without affecting platelet adhesion to collagen fibrils. Consistent with these findings, Tablysin-15 displays antithrombotic properties in vivo suggesting that it is a useful tool to block ?IIb?3, or as a prototype to develop antithrombotics. The RGD motif in the unique sequence of Tablysin-15 represents a novel template for studying the structure-function relationship of the disintegrin family of inhibitors. PMID:21475772

Ma, Dongying; Xu, Xueqing; An, Su; Liu, Huan; Yang, Xuening; Andersen, John F.; Wang, Yipeng; Tokumasu, Fuyuki; Ribeiro, Jose M. C.; Francischetti, Ivo M. B.; Lai, Ren

2012-01-01

225

Identification of bothrojaracin-like proteins in snake venoms from Bothrops species and Lachesis muta.  

PubMed

Bothrojaracin, a 27 kDa protein isolated from Bothrops jararaca venom, forms a non-covalent complex with thrombin, thus blocking its activity. We have previously identified a bothrojaracin-like protein in B. alternatus venom [Castro, H.C., Dutra, D.L.S., Oliveira-Carvalho, A.L., Zingali, R.B., 1998. Bothroalternin, an inhibitor of thrombin from the venom of Bothrops alternatus. Toxicon 36, 1903-1912]. In this report, we have examined snake venoms from six different Bothrops species (B. atrox, B. cotiara, B. jararacussu, B. moojeni and B. neuwiedi), from Lachesis muta and from Crotalus durissus terrificus for the presence of bothrojaracin-like proteins, which we define here as 27 kDa proteins that are immunologically related to bothrojaracin and that inhibit thrombin-induced platelet aggregation. The immunological analysis of these venoms by different techniques indicated the existence of at least one protein recognized by anti-bothrojaracin serum in all venoms tested. Bothrojaracin-like proteins were purified from all crude venoms, except for C. d. terrificus, by a single-step procedure using a thrombin affinity column (PPACK-thrombin-Sepharose). Retained material that inhibits thrombin-induced platelet aggregation was found in a different proportion in each species. Under non-reducing conditions, SDS-PAGE of this material revealed several bands between 20-60 kDa; only those bands corresponding to 27 kDa were recognized by anti-bothrojaracin serum. ELISA confirmed the greater bothrojaracin immunoreactivity of proteins present in B. atrox and B. cotiara as compared to other Bothrops species. Smaller amounts of proteins related to bothrojaracin were found in L. muta venom and were absent from the venom of C. d. terrificus. Our results thus suggest that bothrojaracin-like proteins are widely distributed among Bothrops genera. PMID:10414865

Castro, H C; Fernandes, M; Zingali, R B

1999-10-01

226

Biochemical and biological properties of phospholipases A(2) from Bothrops atrox snake venom.  

PubMed

Phospholipases A(2) (PLA(2)s), of molecular mass 13-15kDa, are commonly isolated from snake venom. Two myotoxins with PLA(2) activity, BaPLA(2)I and BaPLA(2)III, with estimated molecular masses of 15kDa were isolated from the venom of Bothrops atrox using Sephacryl S-100-HR and reverse-phase chromatography. BaPLA(2)I was basic, with a pI of 9.1, while BaPLA(2)III was neutral with a pI of 6.9. On a molecular basis, BaPLA(2)III exhibited higher catalytic activity on synthetic substrates than BaPLA(2)I. Comparison of the N-terminal residues of BaPLA(2)I with other PLA(2) proteins from snake venoms showed that it has the highest homology (94%) with B. asper myotoxin II and homology with a PLA(2) Lys(49) from B. atrox (89%). In contrast, BaPLA(2)III demonstrated 75, 72, and 71% homology with PLA(2) from Vipera ammodytes meridionalis, B. jararacussu, and B. jararaca, respectively. BaPLA(2)I and BaPLA(2)III were capable, in vitro, of inducing mast cell degranulation and, in vivo, of causing creatine kinase release, edema, and myonecrosis typical of PLA(2)s from snake venoms, characterized by rapid disruption of the plasma membrane as indicated by clumping of myofilaments and necrosis of affected skeletal muscle cells. BaPLA(2)I- and BaPLA(2)III-specific monoclonal and polyclonal antibodies, although incapable of neutralizing PLA(2) edematogenic activity, blocked myonecrosis efficiently in an in vivo neutralization assay. The results presented herein suggest that the biological active site responsible for edema induction by these two PLA(2) enzymes is distinct from the myonecrosis active site and is not dependent upon the catalytic activity of the PLA(2) enzyme. PMID:12234622

Kanashiro, Milton M; de Cássia M Escocard, Rita; Petretski, Jorge H; Prates, Maura V; Alves, Elias W; Machado, Olga L T; da Silva, Wilmar Dias; Kipnis, Thereza L

2002-10-01

227

Comparison of indirect and direct approaches using ion-trap and Fourier transform ion cyclotron resonance mass spectrometry for exploring viperid venom proteomes.  

PubMed

In a sense, the field of snake venom proteomics has been under investigation since the very earliest biochemical studies where it was soon recognized that venoms are comprised of complex mixtures of bioactive molecules, most of which are proteins. Only with the re-emergence of 2D polyacrylamide gel electrophoresis (2D PAGE) and the recent developments in mass spectrometry for the identification/characterization of proteins coupled with venom gland transcriptomes has the field of snake venom proteomics began to flourish and provide exciting insights into the protein composition of venoms and subsequently their pathological activities. In this manuscript we will briefly discuss the state of snake venom proteomics followed by the presentation of several straightforward experiments designed to explore approaches to investigating venom proteomics. The first set of experiments used 1D gel electrophoresis (1D PAGE) of Crotalus atrox venom followed by slice-by-slice analysis of the proteins using liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS). In the second set of experiments, C. atrox and Bothrops jararaca venoms were subjected to in-solution digestion followed by Fourier transform ion cyclotron resonance (FTICR) LC/MS/MS. The peptide ion-maps of these venoms were compared along with the proteins identified. In addition, the results were compared to the results observed from the 1D PAGE approach. From these studies it is clear that sample de-complexation/fractionation before mass spectrometry is still the best approach for maximum proteome coverage. Furthermore, comparison of venom proteomes based on tryptic peptide identities between the proteomes is not particularly effective since there does not appear to be a sufficient number of such identical peptides, derived from related proteins, present in venoms. Finally, as has previously been recognized without either better databases of venom protein sequences or facile and rapid de novo sequencing technologies for mass spectrometry, snake venom proteome investigation will remain a laborious task. PMID:16574175

Fox, Jay W; Ma, Li; Nelson, Kristina; Sherman, Nicholas E; Serrano, Solange M T

2006-05-01

228

A multifaceted analysis of viperid snake venoms by two-dimensional gel electrophoresis: an approach to understanding venom proteomics.  

PubMed

The complexity of Viperid venoms has long been appreciated by investigators in the fields of toxinology and medicine. However, it is only recently that the depth of that complexity has become somewhat quantitatively and qualitatively appreciated. With the resurgence of two-dimensional gel electrophoresis (2-DE) and the advances in mass spectrometry virtually all venom components can be visualized and identified given sufficient effort and resources. Here we present the use of 2-DE for examining venom complexity as well as demonstrating interesting approaches to selectively delineate subpopulations of venom proteins based on particular characteristics of the proteins such as antibody cross-reactivity or enzymatic activities. 2-DE comparisons between venoms from different species of the same genus (Bothrops) of snake clearly demonstrated both the similarity as well as the apparent diversity among these venoms. Using liquid chromatography/tandem mass spectrometry we were able to identify regions of the two-dimensional gels from each venom in which certain classes of proteins were found. 2-DE was also used to compare venoms from Crotalus atrox and Bothrops jararaca. For these venoms a variety of staining/detection protocols was utilized to compare and contrast the venoms. Specifically, we used various stains to visualize subpopulations of the venom proteomes of these snakes, including Coomassie, Silver, Sypro Ruby and Pro-Q-Emerald. Using specific antibodies in Western blot analyses of 2-DE of the venoms we have examined subpopulations of proteins in these venoms including the serine proteinase proteome, the metalloproteinase proteome, and the phospholipases A2 proteome. A functional assessment of the gelatinolytic activity of these venoms was also performed by zymography. These approaches have given rise to a more thorough understanding of venom complexity and the toxins comprising these venoms and provide insights to investigators who wish to focus on these venom subpopulations of proteins in future studies. PMID:15627971

Serrano, Solange M T; Shannon, John D; Wang, Deyu; Camargo, Antonio C M; Fox, Jay W

2005-02-01

229

Crotalid snake venom subproteomes unraveled by the antiophidic protein DM43.  

PubMed

Snake venoms are mixtures of proteins and peptides with different biological activities, many of which are very toxic. Several animals, including the opossum Didelphis aurita, are resistant to snake venoms due to the presence of neutralizing factors in their blood. An antihemorrhagic protein named DM43 was isolated from opossum serum. It inhibits snake venom metalloproteinases through noncovalent complex formation with these enzymes. In this study, we have used DM43 and proteomic techniques to explore snake venom subproteomes. Four crotalid venoms were chromatographed through an affinity column containing immobilized DM43. Bound fractions were analyzed by one- and two-dimensional gel electrophoresis, followed by identification by MALDI-TOF/TOF mass spectrometry. With this approach, we could easily visualize and compare the metalloproteinase compositions of Bothrops atrox, Bothrops jararaca, Bothrops insularis, and Crotalus atrox snake venoms. The important contribution of proteolytic processing to the complexity of this particular subproteome was demonstrated. Fractions not bound to DM43 column were similarly analyzed and were composed mainly of serine proteinases, C-type lectins, C-type lectin-like proteins, l-amino acid oxidases, nerve growth factor, cysteine-rich secretory protein, a few metalloproteinases (and their fragments), and some unidentified spots. Although very few toxin families were represented in the crotalid venoms analyzed, the number of protein spots detected was in the hundreds, indicating an important protein variability in these natural secretions. DM43 affinity chromatography and associated proteomic techniques proved to be useful tools to separate and identify proteins from snake venoms, contributing to a better comprehension of venom heterogeneity. PMID:19267469

Rocha, Surza L G; Neves-Ferreira, Ana G C; Trugilho, Monique R O; Chapeaurouge, Alex; León, Ileana R; Valente, Richard H; Domont, Gilberto B; Perales, Jonas

2009-05-01

230

Immunome and venome of Bothrops jararacussu: a proteomic approach to study the molecular immunology of snake toxins.  

PubMed

A combination of anti-bothropic and anti-crotalic sera has been reported to be more effective in neutralizing the effects of Bothrops jararacussu venom than anti-bothropic serum alone. The role of proteins from B. jararacussu venom in the horse immune response was evaluated via the analysis of cross-reactivity with homologous and heterologous sera. Many of the proteins in B. jararacussu venom were identified via 2D gel electrophoresis. Western blots revealed that anti-jararacussu showed higher reactivity to l-aminoxidase (LAOs) and snake venom metalloproteinase, (SVMPs) and weaker reactivity towards Snake venom serine proteases (SVSPs), PLA(2), C-type lectin and cysteine-rich proteins. Anti-jararaca preferentially recognized LAOs, SVMPs and SVSPs. Both of these sera failed to recognize low-molecular weight proteins. Anti-crotalic serum clearly recognized LAOs, C-type lectin, SVSP, cysteine-rich proteins, SVMP and Asp49-PLA(2). The cross-reactivity with anti-PLA(2) revealed the immunoreactivity of these antibodies to proteins with molecular masses in a range that is poorly recognized by other studied anti-sera. Our results suggest that the contribution of anti-crotalic serum to the neutralization of B. jararacussu by may be due to its cross-reactivity with proteins such as C-type lectins, SVSPs, Asp49-PLA(2). These results also reinforce the importance of neutralizing the highly toxic proteins inclusive those with low immunogenicity in commercial antivenom production to obtain a highly protective serum against snake venoms. PMID:20060013

Correa-Netto, Carlos; Teixeira-Araujo, Ricardo; Aguiar, Aniesse Silva; Melgarejo, Aníbal Rafael; De-Simone, Salvatore Giovanni; Soares, Márcia Regina; Foguel, Debora; Zingali, Russolina Benedeta

2010-06-15

231

Art exhibit focuses on African astronomy  

NASA Astrophysics Data System (ADS)

Connections between Africans and astronomy are the focus of a new exhibition in the National Museum of African Art in Washington, D. C. “African Cosmos: Stellar Arts,” which includes artwork, cultural items, and scientific displays from ancient to contemporary times, is the first major exhibit “that brings together arts and science focused on Africa's contribution to keen observations of the heavens over time,” curator Christine Mullen Kreamer said at a 20 June news briefing. Among the exhibit's nearly 100 objects are an ancient Egyptian mummy board that includes a representation of the sky goddess Nut, sculptures by the Dogon people of Mali depicting figures in relation to the cosmos, a video that uses data from two square degrees of the Hubble Space Telescope Cosmic Evolution Survey, and a nearly floor-to-ceiling “Rainbow Serpent” constructed of plastic containers by Benin artist Hazoume. An untitled acrylic painting (Figure 1) by South African Gavin Jantjes evokes a myth of the Khoi San people of southern Africa, as it portrays a girl throwing evening fire embers into the night sky, where they remained as the Milky Way.

Showstack, Randy

2012-07-01

232

Adaptive Evolution of the Venom-Targeted vWF Protein in Opossums that Eat Pitvipers  

PubMed Central

The rapid evolution of venom toxin genes is often explained as the result of a biochemical arms race between venomous animals and their prey. However, it is not clear that an arms race analogy is appropriate in this context because there is no published evidence for rapid evolution in genes that might confer toxin resistance among routinely envenomed species. Here we report such evidence from an unusual predator-prey relationship between opossums (Marsupialia: Didelphidae) and pitvipers (Serpentes: Crotalinae). In particular, we found high ratios of replacement to silent substitutions in the gene encoding von Willebrand Factor (vWF), a venom-targeted hemostatic blood protein, in a clade of opossums known to eat pitvipers and to be resistant to their hemorrhagic venom. Observed amino-acid substitutions in venom-resistant opossums include changes in net charge and hydrophobicity that are hypothesized to weaken the bond between vWF and one of its toxic snake-venom ligands, the C-type lectin-like protein botrocetin. Our results provide the first example of rapid adaptive evolution in any venom-targeted molecule, and they support the notion that an evolutionary arms race might be driving the rapid evolution of snake venoms. However, in the arms race implied by our results, venomous snakes are prey, and their venom has a correspondingly defensive function in addition to its usual trophic role. PMID:21731638

Jansa, Sharon A.; Voss, Robert S.

2011-01-01

233

Combining Total Monte Carlo and Benchmarks for Nuclear Data Uncertainty Propagation on a Lead Fast Reactor's Safety Parameters  

NASA Astrophysics Data System (ADS)

Analyses are carried out to assess the impact of nuclear data uncertainties on keff for the European Lead Cooled Training Reactor (ELECTRA) using the Total Monte Carlo method. A large number of 239Pu random ENDF-formatted libraries generated using the TALYS based system were processed into ACE format with NJOY-99.336 code and used as input into the Serpent Monte Carlo neutron transport code to obtain distribution in keff. The mean of the keff distribution obtained was compared with the major nuclear data libraries, JEFF-3.1.1, ENDF/B-VII.1 and JENDL-4.0. A method is proposed for the selection of benchmarks for specific applications using the Total Monte Carlo approach. Finally, an accept/reject criterion was investigated based on ?2 values obtained using the 239Pu Jezebel criticality benchmark. It was observed that nuclear data uncertainties in keff were reduced considerably from 748 to 443 pcm by applying a more rigid acceptance criteria for accepting random files.

Alhassan, E.; Sjöstrand, H.; Duan, J.; Gustavsson, C.; Koning, A. J.; Pomp, S.; Rochman, D.; Österlund, M.

2014-04-01

234

The story of the condom  

PubMed Central

Condoms have been a subject of curiosity throughout history. The idea of safer sex has been explored in ancient and modern history, and has been used to prevent venereal diseases. We conducted a historical and medical review of condoms using primary and secondary sources as well as using the RSM library and the internet. These resources show that the first use of a condom was that of King Minos of Crete. Pasiphae, his wife, employed a goat's bladder in the vagina so that King Minos would not be able to harm her as his semen was said to contain “scorpions and serpents” that killed his mistresses. To Egyptians, condom-like glans caps were dyed in different colours to distinguish between different classes of people and to protect themselves against bilharzia. The Ancient Romans used the bladders of animals to protect the woman; they were worn not to prevent pregnancy but to prevent contraction of venereal diseases. Charles Goodyear, the inventor, utilized vulcanization, the process of transforming rubber into malleable structures, to produce latex condoms. The greater use of condoms all over the world in the 20th and 21st centuries has been related to HIV. This account of the use of condoms demonstrates how a primitive idea turned into an object that is used globally with a forecast estimated at 18 billion condoms to be used in 2015 alone. PMID:23671357

Khan, Fahd; Mukhtar, Saheel; Dickinson, Ian K.; Sriprasad, Seshadri

2013-01-01

235

Birmingham Conservatoire Historical Instrument Collection  

NSDL National Science Digital Library

If you have ever had a penchant to check out an ancient flageolet or a historic bass horn, this delightful online collection from the Birmingham Conservatoire Historical Instrument Collection is just the ticket. The project was developed by Professor George Caird and his colleagues at Birmingham City University, and funding for the project was provided by Arts & Humanities Research Council. From the homepage, visitors can browse the catalog of instruments by name or by maker, look over a host of images, and listen to some excellent audio samples of the instruments. The instruments are divided into categories that include "Trombones", "Plucked Strings", "Keyboards", and "Serpents, Ophicleides and Bass Horns". Each instrument is accompanied by information about its place of origin, its maker, its overall size, and numerous photographs. Moving on, the "Audio Resources" area is quite a pip, and visitors can listen to expert musicians playing everything from an 1836 piccolo to a folded coach horn making its way through Mozart's Post Horn Serenade.

236

Micrurus snake venoms activate human complement system and generate anaphylatoxins  

PubMed Central

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 ? chain of the component C3, but not of the C4, which was inhibited by 1,10 Phenanthroline, suggesting the presence of a C3? 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. PMID:22248157

2012-01-01

237

Changes in deep-water epibenthic megafaunal assemblages in relation to seabed slope on the Nigerian margin  

NASA Astrophysics Data System (ADS)

Local-scale habitat heterogeneity associated with changes in slope is a ubiquitous feature of bathyal continental margins. The response of deep-sea species to high habitat heterogeneity is poorly known and slope can be used as a proxy for many important ecological variables, such as current flow, sedimentation and substratum type. This study determines how slope angle effects megafaunal species density and diversity at the Usan field, offshore Nigeria, between 740 and 760 m depth. This deep-water area is increasingly exploited for hydrocarbons, yet lacking in baseline biological information. Replicated remotely operated vehicle video transect surveys were carried out using industry infrastructure (through the SERPENT Project) at a representative range of slopes (1°, 3°, 11° and 29°). Twenty-four species of benthic megafaunal invertebrate were found, numerically dominated by the echinoid Phormosoma placenta, and nine species of fish were observed. Megafaunal invertebrate deposit feeder density decreased significantly with increasing slope (density range 0.503-0.081 individuals m-2). Densities of megafaunal suspension feeders were very low except at the highest slope site (mean density 0.17 m-2). Overall species richness was greater on steeper slopes, although the richness of deposit feeders was not affected. Reduced labile organic matter in sediments on steeper slopes likely reduced deposit feeder densities, but increased current flow at higher slopes allowed both increased richness and density of suspension feeders.

Jones, Daniel O. B.; Mrabure, Charles O.; Gates, Andrew R.

2013-08-01

238

Do Cross-circle Designs, the Mayan World Tree, Chitto Tustenuggee's, and Miami's Tequesta, Sites have Analogs in Brazil as they have in Peru, Europe, and Africa?  

NASA Astrophysics Data System (ADS)

Florida's Miami Tequesta site conveys information about potential tornadoes, hurricanes, and even earthquakes. It is visually analogous to cross-circle designs, like other equivalent sites we have located, as in Maine, New Hampshire, in Medicine Wheels, and elsewhere. We focus on the detectable effects of time-and-place dependent electromagnetic signals. Non-technologic societies, and individuals, still find and use them, even today, especially in places like Cuzco, Peru. Modes of detection involve senses, such as sensitive, observant eyesight, and electromagnetically induced nerve signals interpreted as tinnitus, as traditionally indicated by ``Kokopelli's'' flute-playing, ``pins and needles,'' or even odor sensations. Recorded events show that youthful children are sometimes involved, as by Pacal's Classic-Mayan-era son, who became Kan Balum, Serpent Jaguar. Our intent is to check whether similar signals can be technologically identified in Brazil and New England. Site information investigated by us seems to be driven by the electromagnetic field. Enigmatic Brazilian locations should be technologically investigated with site correlations to other possible analogs, such as Florida's Chitto Tustenuggee site at Miramar. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.NES07.C2.6

Ataide, Jade; Mc Leod, Roger; Mc Leod, David

2007-04-01

239

Commiphora molmol in human welfare (review article).  

PubMed

The origins of myrrh and frankincense are traced to the Arabian Peninsula. According to Herodotus (5th century BC): "Arabia is the only country which produces frankincense, myrrh, cassia and cinnamon ... the trees bearing the frankincense are guarded by winged serpents of small size and various colors." Diodorus Siculus writes, in the second half of the first century BC, that "all of Arabia exudes a most delicate fragrance; even the seamen passing by Arabia can smell the strong fragrance that gives health and vigor." He also mentioned gold mines so pure that no smelting was necessary. The Magi, carrying myrrh, frankincense, and gold, came from the East: Arabia. The frankincense trade route, with transport by donkeys and later by camel caravans, reached Jerusalem and Egypt from the Dhofar region of what is today Oman, through Yemen, turning north to follow the Red Sea coast. It is likely that the same or similar species of the resin-bearing plants grew across the Red Sea in the area that is now Somalia and Ethiopia, while the collection of the gum resins was initiated in Arabia. Myrrh contributed much in the human welfare. This review selected some but not all of the value application of myrrh (Commiphora molmol). PMID:17985580

Al-Mathal, Ebtsam M

2007-08-01

240

226Ra and other radionuclides in water, vegetation, and tissues of beavers (Castor canadensis) from a watershed containing U tailings near Elliot Lake, Canada.  

PubMed

Radionuclide levels were measured in tissues, gut contents, diet items, and water at site of capture, of adult beavers from the Serpent River drainage basin which contains U tailings at Elliot Lake, Ontario, and from nearby control sites. Levels of (226)Ra in beaver bone, muscle and kidney were highest in animals from locations close to U tailings; liver levels did not vary by site. Environmental (226)Ra levels were within ranges previously reported at these or similar locations elsewhere; levels in beaver gut contents reflected levels in diet items. Concentration ratios exceeded unity only between some vegetation items and beaver bone at the Elliot Lake site and were less than 0.19 between vegetation and other tissues. In two beavers with tissue levels of (226)Ra higher than other sampled, neither (232)Th nor (230)Th were detected in bone, muscle or liver tissues. U-238 was measurable in bone, muscle and liver, (228)Th in bone, (210)Po bone, muscle and liver; and (210)Pb was measurable only in bone. Estimated yearly intakes of radionuclides by people eating beavers were calculated to be below current allowable levels set by the Canadian regulatory authorities. PMID:15092150

Clulow, F V; Mirka, M A; Davé, N K; Lim, T P

1991-01-01

241

Large Cretaceous sphenodontian from Patagonia provides insight into lepidosaur evolution in Gondwana.  

PubMed

Sphenodontian reptiles successfully radiated during Triassic and Jurassic times, but were driven almost to extinction during the Cretaceous period. The sparse Early Cretaceous record of sphenodontians has been interpreted as reflecting the decline of the group in favour of lizards, their suspected ecological successors. However, recent discoveries in Late Cretaceous beds in Patagonia partially modify this interpretation. Numerous skeletons of a new sphenodontian, Priosphenodon avelasi gen. et sp. nov., were collected from a single locality in the Cenomanian-Turonian Candeleros Formation, where it is more abundant than any other tetrapod group recorded in the quarry (for example, Crocodyliformes, Serpentes, Dinosauria and Mammalia). Adult specimens of Priosphenodon reached one metre in length, larger than any previously known terrestrial sphenodontian. Here we propose, using available evidence, that sphenodontians were not a minor component of the Cretaceous terrestrial ecosystems of South America, and that their ecological replacement by squamates was delayed until the early Tertiary. The new discovery helps to bridge the considerable gap in the fossil record (around 120 million years) that separates the Early Cretaceous sphenodontians from their living relatives (Sphenodon). PMID:14534584

Apesteguía, Sebastián; Novas, Fernando E

2003-10-01

242

Diversity, natural history, and geographic distribution of snakes in the Caatinga, Northeastern Brazil.  

PubMed

The present study is a synthesis on snake diversity and distribution in the Caatinga region of northeastern Brazil, providing an updated species list and data on natural history and geographic distribution. Our study is based on the careful revision of 7,102 voucher specimens, housed in 17 herpetological collections, complemented by data on taxonomic literature. We recorded a total of 112 snake species in the Caatinga, belonging to nine families: Anomalepididae, Leptotyphlopidae, Typhlopidae, Aniliidae, Boidae, Viperidae, Elapidae, Colubridae, and Dipsadidae. Our list includes at least 13 never recorded species for this region, as well as distribution records for all species known from the Caatinga (including expansion and new records of distribution). The snake assemblage of the Caatinga is complex, sharing species with other continental open areas (38.4%), forested areas (27.7%), and both open and forested areas (32.1%). The richest areas were isolated plateaus, followed by contact areas, semi-arid caatinga, and sandy dunes of the São Franscisco River. We identified 22 Caatinga endemic species with the sandy dunes of São Franscico River showing the highest endemism level (12 species, with six endemic species restricted to the area) followed by semi-arid caatinga, and isolated plateaus (eight endemic species each, and six and three endemic species with restricted distribution to each area, respectively). Most species show relatively restricted ranges in parts of the Caatinga. The snake assemblage in Caatinga includes mainly terrestrial species (38.4%), followed by fossorial/cryptozoic (26.8%), arboreal/semi-arboreal (26.8%), and aquatic/semi-aquatic (7.1%) species. Vertebrates are the most important dietary item (80.4%), with 56.6% of species being generalist consumers of this kind of prey; 24.4% are frog-eaters, 7.8% prey on caecilians/amphisbaenians, 6.7% lizard-eaters, 3.3% mammal-eaters, and 1.1% are fish-eaters. Only 18.7% of the snakes eat invertebrate prey, as arthropods, annelids, and mollusks. In relation to time of activity, 35.7% of snakes are both diurnal and nocturnal, 33.0% are strictly nocturnal, and 30.4% are diurnal. The data provided herein increase the list of Caatinga snake species from 50 to 112, and includes detailed maps and information on geographic distribution. The Caatinga snake assemblage shows high richness and endemism levels, and our results highlight the usefulness of basic natural history data and revision of voucher specimens as baseline information for biogeographic studies and conservation strategies.  PMID:25283535

Guedes, Thaís B; Nogueira, Cristiano; Marques, Otavio A V

2014-01-01

243

The crucial role of the MyD88 adaptor protein in the inflammatory response induced by Bothrops atrox venom.  

PubMed

Most snake accidents in North Brazil are attributed to Bothrops atrox, a snake species of the Viperidae family whose venom simultaneously induces local and systemic effects in the victims. The former are clinically more important than the latter, as they cause severe tissue lesions associated with strong inflammatory responses. Although several studies have shown that inflammatory mediators are produced in response to B. atrox venom (BaV), there is little information concerning the molecular pathways involved in innate immune system signaling. Myeloid differentiation factor 88 (MyD88) is an adaptor molecule responsible for transmitting intracellular signals from most toll-like receptors (TLRs) after they interact with pathogen-associated molecular patterns (PAMPs) or other stimuli such as endogenous damage-associated molecular patterns (DAMPs). The MyD88-dependent pathway leads to activation of transcription factors, which in turn induce synthesis of inflammatory mediators such as eicosanoids, cytokines and chemokines. The aim of this study was to investigate the involvement of MyD88 on the acute inflammatory response induced by BaV. Wild-type (WT) C57BL/6 mice and MyD88 knockout (MyD88(-/-)) mice were intraperitoneally injected with BaV. Compared to WT mice, MyD88(-/-) animals showed an impaired inflammatory response to BaV, with lower influx of polymorphonuclear and mononuclear cells to the peritoneal cavity. Furthermore, peritoneal leukocytes from BaV-injected MyD88(-/-) mice did not induce COX-2 or LTB4 protein expression and released low concentrations of PGE2. These mice also failed to produce Th1 and Th17 cytokines and CCL-2, but IL-10 levels were similar to those of BaV-injected WT mice. Our results indicate that MyD88 signaling is required for activation of the inflammatory response elicited by BaV, raising the possibility of developing new therapeutic targets to treat Bothrops sp. poisoning. PMID:23474268

Moreira, Vanessa; Teixeira, Catarina; Borges da Silva, Henrique; D'Império Lima, Maria Regina; Dos-Santos, Maria Cristina

2013-06-01

244

Dexamethasone antagonizes the in vivo myotoxic and inflammatory effects of Bothrops venoms.  

PubMed

In the present work we investigated the toxic activities of two Bothrops snake venoms using in vivo and in vitro experimental protocols in mice and tested the protective effect of dexamethasone (DEXA) in different conditions, comparing it with the polyvalent antivenom. We also expanded the investigations on the antiophidic effect of the Eclipta prostrata (EP) crude extract. The administration of Bothrops jararaca and Bothrops jararacussu snake venoms induced muscle damage demonstrated in vivo by the elevation on plasma creatine kinase (CK) activity in mice and by the decrease in CK content in the extensor digitorum longus (EDL) muscle of these animals, and in vitro by the increase in the rate of CK release from the isolated EDL muscle. We also observed inflammatory response following perimuscular injection of B. jararacussu venom (1.0 mg/kg). Treatment with DEXA (1.0 mg/kg) preserved over 50% of the EDL muscle CK content in vivo when evaluated 24 and 72 h after the injection of B. jararacussu venom in mice, and likewise reduced about 20% of the edema induced by this venom. DEXA reduced in 50% the presence of inflammatory cells and their activity in EDL muscle. The EP extract (50 mg/kg) showed similar ability in preventing the induction of edema and the decrease in muscle CK content, and its association with DEXA showed additive effect. EP reduced over 77% of the plasma CK activity induced by the B. jararacussu venom. In the in vitro experiments, DEXA was not able to change the rate of CK release from EDL muscles exposed to 25 ?g/mL of B. jararacussu venom, neither to prevent the fall in the amplitude of the indirectly evoked twitch at the phrenic-diaphragm preparation. EP extract showed otherwise a protective effect on these protocols, reaching up to 100% of protection when concentrations of 50.0 and 100.0 ?g/mL were used. Altogether our results show that inflammation is at least in part responsible for the tissue damage induced by Bothrops snake venoms, once the steroidal anti-inflammatory drug dexamethasone was able to decrease the myotoxic effects of these venoms, by reducing the inflammatory response to the venom injection. PMID:23416798

Patrão-Neto, Fernando Chagas; Tomaz, Marcelo Amorim; Strauch, Marcelo Abrahão; Monteiro-Machado, Marcos; Rocha, José Roberto Da Silva; Borges, Paula Alvarenga; Calil-Elias, Sabrina; Melo, Paulo A

2013-07-01

245

Myotoxic phospholipases A(2) in bothrops snake venoms: effect of chemical modifications on the enzymatic and pharmacological properties of bothropstoxins from Bothrops jararacussu.  

PubMed

Venoms from eight Bothrops spp. were fractionated by ion-exchange chromatography on CM-Sepharose at pH 8.0 for the purification of myotoxins. Chromatographic profiles showed differences regarding myotoxic components among these venoms. B. alternatus, B. atrox and B. jararaca venoms did not show the major basic myotoxic fractions identified in the other venoms. Polyacrylamide gel electrophoresis for basic proteins also showed distinct patterns for these toxins. In vivo, all the isolated myotoxins induced release of creatine kinase due to necrosis of muscle fibers, accompanied by polymorphonuclear cell infiltration, and edema in the mouse paw. In addition, the toxins showed cytotoxic and liposome-disrupting activities in vitro. B. jararacussu bothropstoxins-I (BthTX-I) and II (BthTX-II) were submitted to chemical modifications of: His, by 4-bromophenacyl bromide (BPB) or photooxidation by Rose Bengal (RB); Tyr, by 2-nitrobenzenesulphonyl fluoride (NBSF); and Trp, by o-nitrophenylsulphenyl chloride (NPSC). The myotoxic and cytotoxic activities of BthTX-I, a Lys49 PLA(2) homologue, after modification by BPB, RB, NBSF and NPSC, were reduced to 50%, 20%, 75%, 65% and 13%, 0.5%, 76%, 58%, respectively. However, the edema-inducing and liposome-disrupting activities were not significantly reduced by the above modifications. BPB-treated BthTX-II, an Asp49 PLA(2) homologue, lost most of its catalytic, indirect hemolytic, anticoagulant, myotoxic and cytotoxic activities. The edema-inducing and liposome-disrupting activities were reduced to 50% and 80%, respectively. Lethality caused by BthTX-I and -II was strongly reduced after treatment with BPB or RB, but only partially with NBSF or NPSC. BthTX-I and -II, both native or modified, migrated similarly in a charge-shift electrophoresis. Antibodies raised against BthTX-I or -II, B. asper Basp-II and the C-terminal 115-129 peptide from Basp-II did not show significant differences in their cross-reactivity with the modified toxins, except with RB photooxidized toxins. PMID:11018293

Andrião-Escarso, S H; Soares, A M; Rodrigues, V M; Angulo, Y; Díaz, C; Lomonte, B; Gutiérrez, J M; Giglio, J R

2000-08-01

246

Peptidomics of Three Bothrops Snake Venoms: Insights Into the Molecular Diversification of Proteomes and Peptidomes*  

PubMed Central

Snake venom proteomes/peptidomes are highly complex and maintenance of their integrity within the gland lumen is crucial for the expression of toxin activities. There has been considerable progress in the field of venom proteomics, however, peptidomics does not progress as fast, because of the lack of comprehensive venom sequence databases for analysis of MS data. Therefore, in many cases venom peptides have to be sequenced manually by MS/MS analysis or Edman degradation. This is critical for rare snake species, as is the case of Bothrops cotiara (BC) and B. fonsecai (BF), which are regarded as near threatened with extinction. In this study we conducted a comprehensive analysis of the venom peptidomes of BC, BF, and B. jararaca (BJ) using a combination of solid-phase extraction and reversed-phase HPLC to fractionate the peptides, followed by nano-liquid chromatography-tandem MS (LC-MS/MS) or direct infusion electrospray ionization-(ESI)-MS/MS or MALDI-MS/MS analyses. We detected marked differences in the venom peptidomes and identified peptides ranging from 7 to 39 residues in length by de novo sequencing. Forty-four unique sequences were manually identified, out of which 30 are new peptides, including 17 bradykinin-potentiating peptides, three poly-histidine-poly-glycine peptides and interestingly, 10 l-amino acid oxidase fragments. Some of the new bradykinin-potentiating peptides display significant bradykinin potentiating activity. Automated database search revealed fragments from several toxins in the peptidomes, mainly from l-amino acid oxidase, and allowed the determination of the peptide bond specificity of proteinases and amino acid occurrences for the P4-P4? sites. We also demonstrate that the venom lyophilization/resolubilization process greatly increases the complexity of the peptidome because of the imbalance caused to the venom proteome and the consequent activity of proteinases on venom components. The use of proteinase inhibitors clearly showed different outcomes in the peptidome characterization and suggested that degradomic-peptidomic analysis of snake venoms is highly sensitive to the conditions of sampling procedures. PMID:22869554

Tashima, Alexandre K.; Zelanis, Andre; Kitano, Eduardo S.; Ianzer, Danielle; Melo, Robson L.; Rioli, Vanessa; Sant'anna, Savio S.; Schenberg, Ana C. G.; Camargo, Antonio C. M.; Serrano, Solange M. T.

2012-01-01

247

A new structurally atypical bradykinin-potentiating peptide isolated from Crotalus durissus cascavella venom (South American rattlesnake).  

PubMed

Venom glands of some snakes synthesize bradykinin-potentiating peptides (BPP's) which increase bradykinin-induced hypotensive effect and decrease angiotensin I vasopressor effect by angiotensin-converting enzyme (ACE) inhibition. The present study shows a new BPP (BPP-Cdc) isolated from Crotalus durissus cascavella venom: Pro-Asn-Leu-Pro-Asn-Tyr-Leu-Gly-Ile-Pro-Pro. Although BPP-Cdc presents the classical sequence IPP in the C-terminus, it has a completely atypical N-terminal sequence, which shows very low homology with all other BPPs isolated to date. The pharmacological effects of BPP-Cdc were compared to BBP9a from Bothrops jararaca and captopril. BPP-Cdc (1 ?M) significantly increased BK-induced contractions (BK; 1 ?M) on the guinea pig ileum by 267.8% and decreased angiotensin I-induced contractions (AngI; 10 nM) by 62.4% and these effects were not significantly different from those of BPP9a (1 ?M) or captopril (200 nM). Experiments with 4-week hypertensive 2K-1C rats show that the vasopressor effect of AngI (10 ng) was decreased by 50 ?g BPP-Cdc (69.7%), and this result was similar to that obtained with 50 ?g BPP9a (69.8%). However, the action duration of BPP-Cdc (60 min) was 2 times greater than that of BPP-9a (30 min). On the other hand, the hypotensive effect of BK (250 ng) was significantly increased by 176.6% after BPP-Cdc (50 ?g) administration, value 2.5 times greater than that obtained with BPP9a administered at the same doses (71.4%). In addition, the duration of the action of BPP-Cdc (120 min) was also at least 4 times greater than that of BPP-9a (30 min). Taken together, these results suggest that BPP-Cdc presents more selective action on arterial blood system than BPP9a. Besides the inhibition of ACE, it may present other mechanisms of action yet to be elucidated. PMID:25091347

Lopes, Denise M; Junior, Norberto E G; Costa, Paula P C; Martins, Patrícia L; Santos, Cláudia F; Carvalho, Ellaine D F; Carvalho, Maria D F; Pimenta, Daniel C; Cardi, Bruno A; Fonteles, Manassés C; Nascimento, Nilberto R F; Carvalho, Krishnamurti M

2014-11-01

248

Insights into cardiovascular effects of proline-rich oligopeptide (Bj-PRO-10c) revealed by structure-activity analyses: dissociation of antihypertensive and bradycardic effects.  

PubMed

We have previously reported that the proline-rich decapeptide from Bothrops jararaca (Bj-PRO-10c) causes potent and sustained antihypertensive and bradycardic effects in SHR. These activities are independent of ACE inhibition. In the present study, we used the Ala-scan approach to evaluate the importance of each amino acid within the sequence of Bj-PRO-10c (Pyr(1)-Asn(2)-Trp(3)-Pro(4)-His(5)-Pro(6)-Gln(7)-Ile(8)-Pro(9)-Pro(10)). The antihypertensive and bradycardic effects of the analogues Bj-PRO-10c Ala(3), Bj-PRO-10c Ala(7), Bj-PRO-10c Ala(8) were similar to those of Bj-PRO-10c, whereas the analogues Bj-PRO-10c Ala(2), Bj-PRO-10c Ala(4), Bj-PRO-10c Ala(5), Bj-PRO-10c Ala(9), and Bj-PRO-10c Ala(10) kept the antihypertensive activity and lost bradycardic activity considerably. In contrast, Bj-PRO-10c Ala(1) and Bj-PRO-10c Ala(6) were unable to provoke any cardiovascular activity. In summary, we demonstrated that (1) the Pyr(1) and Pro(6) residues are essential for both, the antihypertensive and bradycardic effects of Bj-PRO-10c; (2) Ala-scan approach allowed dissociating blood pressure reduction and bradycardic effects. Conformational properties of the peptides were examined by means of circular dichroism (CD) spectroscopy. The different Ala-scan analogues caused either an increase or decrease in the type II polyproline helix content compared to Bj-PRO-10c. The complete loss of activity of the Pro(6) ? Ala(6) mutant is probably due to the fact that in the parent peptide the His(5)-Pro(6) bond can exist in the cis configuration, which could correspond to the conformation of this bond in the bound state. Current data support the Bj-PRO-10c as a promising leader prototype to develop new agents to treat cardiovascular diseases and its co-morbidities. PMID:24337901

Paschoal, Juliana F B; Yamaguchi, Juliana; Miranda, José R R; Carretero, Gustavo; Melo, Robson L; Santos, Robson A S; Xavier, Carlos H; Schreier, Shirley; Camargo, Antonio C M; Ianzer, Danielle

2014-02-01

249

PepExplorer: a similarity-driven tool for analyzing de novo sequencing results.  

PubMed

Peptide spectrum matching is the current gold standard for protein identification via mass-spectrometry-based proteomics. Peptide spectrum matching compares experimental mass spectra against theoretical spectra generated from a protein sequence database to perform identification, but protein sequences not present in a database cannot be identified unless their sequences are in part conserved. The alternative approach, de novo sequencing, can make it possible to infer a peptide sequence directly from a mass spectrum, but interpreting long lists of peptide sequences resulting from large-scale experiments is not trivial. With this as motivation, PepExplorer was developed to use rigorous pattern recognition to assemble a list of homologue proteins using de novo sequencing data coupled to sequence alignment to allow biological interpretation of the data. PepExplorer can read the output of various widely adopted de novo sequencing tools and converge to a list of proteins with a global false-discovery rate. To this end, it employs a radial basis function neural network that considers precursor charge states, de novo sequencing scores, peptide lengths, and alignment scores to select similar protein candidates, from a target-decoy database, usually obtained from phylogenetically related species. Alignments are performed using a modified Smith-Waterman algorithm tailored for the task at hand. We verified the effectiveness of our approach using a reference set of identifications generated by ProLuCID when searching for Pyrococcus furiosus mass spectra on the corresponding NCBI RefSeq database. We then modified the sequence database by swapping amino acids until ProLuCID was no longer capable of identifying any proteins. By searching the mass spectra using PepExplorer on the modified database, we were able to recover most of the identifications at a 1% false-discovery rate. Finally, we employed PepExplorer to disclose a comprehensive proteomic assessment of the Bothrops jararaca plasma, a known biological source of natural inhibitors of snake toxins. PepExplorer is integrated into the PatternLab for Proteomics environment, which makes available various tools for downstream data analysis, including resources for quantitative and differential proteomics. PMID:24878498

Leprevost, Felipe V; Valente, Richard H; Lima, Diogo B; Perales, Jonas; Melani, Rafael; Yates, John R; Barbosa, Valmir C; Junqueira, Magno; Carvalho, Paulo C

2014-09-01

250

Radium-226 levels and concentration ratios between water, vegetation, and tissues of ruffed grouse (Bonasa umbellus) from a watershed with uranium tailings near Elliot Lake, Canada.  

PubMed

Radionuclide levels measured in bone, muscle, kidney and liver tissues, gut contents and diet items of 47 grouse from the Serpent River drainage basin, containing uranium (U) tailings at Elliot Lake, and from control areas in Ontario, showed variation by site and tissue. The mean level of 226radium (Ra) in bones of grouse sampled from Elliot Lake (28.5 mBq g(-1)) was higher than that in bones of birds from a distant control site near Sudbury, Ontario (8.0 mBq g(-1)) but similar to the value in a local control population (28.1 mBq g(-1)). Birds from Mid- and Low-Serpent River basin populations (with 17.1 and 17.7 mBw g(-1), respectively) did not differ from local or distant control populations; muscle, liver and kidney had lower 226Ra concentrations, which did not differ significantly among populations. Levels of 226Ra in the crop contents and intestine did not differ significantly by site and were similar to those of food items consumed by the birds. Stomach content values were higher in birds sampled in Elliot Lake and at the local control site than in those taken at the distant control site; birds sampled downstream from Elliot Lake did not differ from distant controls in this regard. Levels of 232thorium (Th) and 230Th were below detection limits (0.1 microg g(-1) and 5.0 mBq g(-1), respectively) in bone, muscle and liver tissue in two grouse with elevated levels of 226Ra. Other radionuclides were measurable in some tissues: 238U in bone at 0.4 microg g(-1), in muscle to 0.2 microg g(-1), in liver to 1.0 gmg g(-1.), 228Th was found only in muscle (8.0 mBq g(-1)), 210poloniuim (Po) was found in bone, muscle and liver (maxima: 24.0, 7.0, 16.0 mBq g(-1)) with the exception of one muscle sample; 210lead (Pb) was detected in only one liver sample (50.0 mBq g(-1)). Environmental levels fell within ranges previously reported at the sites, or at similar locations elsewhere. Leaves of trembling and largetooth aspen growing in the basin had mean 226Ra levels of 14.8 and 52.7 mBq g(-1) (dry weight) respectively, and fungal material carried up to 215.4 mBq g(-1) (air-dried), with some variation by site. River and lake waters sampled near the U tailings had 118.1 mBq litre(-1) of dissolved 226Ra; at the distant control site the value was 12.1 mBq litre(-1). The concentration ratios (CR) between bone of grouse collected at the Elliot Lake sites and trembling and largetooth aspen leaves were 1.38 and 1.09 (fresh weight basis); from other diet items and to other tissues the values were less than unity. Bone tissue: water ratios, based on dissolved 226Ra levels, ranged to 30.89. People eating grouse from the study area are unlikely to consume radionuclides in excess of limits currently established by Canadian regulatory authorities. PMID:15091976

Clulow, F V; Lim, T P; Davé, N K; Avadhanula, R

1992-01-01

251

Development of 3D full-core ERANOS-2.2/MCNPX-2.7.0 models and neutronic analysis of the BFS-2 zero-power facility  

SciTech Connect

The present paper is addressing the development and validation against experimental data of 3D full-core models of the BFS-2 zero-power fast-reactor using both the deterministic system code ERANOS-2.2 and the stochastic code MCNPX-2.7.0. The model configuration of BFS considered for analysis is the BFS-62-3A benchmark. To extend the - deterministic/stochastic - code-to-code comparison, neutronic parameters, i.e. reactivity, neutron spectrum and reaction rates, were also simulated at the cell level with the Monte Carlo code SERPENT-1.1.7 with two modern data libraries, ENDF-B/VII and JEFF-3.1.1. The BFS-2 critical zero-power facility at the Inst. of Physics and Power Engineering (IPPE) was designed for simulations of the core and shielding of sodium-cooled, fast reactors, for neutron data validation and comparison with experimental results. At the BFS-2 facility, the BFS-62-3A critical benchmark experiment was set-up as a mock-up of the BN-600 reactor, with hybrid MOX fuel and stainless steel reflectors. A UO{sub 2} blanket and a large non-homogeneous stainless-steel reflector surround the core. The lattice is hexagonal of pitch 5.1 cm and metallic dowels are used to keep in central position cylindrical rods made of different types of material (fissile, fertile, blanket, plenum, shielding and absorber). A typical subassembly is formed in piling up various pellets of about 1 cm in height and 4.6 cm in diameter, conferring large heterogeneity in the axial direction. The full-core model development was a complex task due to the large number of subassemblies and the axial subassembly heterogeneity. In ERANOS-2.2, it was necessary to homogenize axially per region the pellets used to form the subassembly. The self-shielded macroscopic cross-sections were calculated using the cell code ECCO in association with JEFF-3.1 and ENDF/B-VI.8 data libraries. The core calculations were performed with broad cross-sections data in 33 neutron energy groups with the solver AVNM in the diffusion approximation, mostly. In MCNPX-2.7.0, a step-by-step approach was used, starting with a model in which the fissile rods were simulated on a homogeneous level, to finally integrate the actual heterogeneous description of the subassemblies. The code-to-code cell analysis performed between ECCO, SERPENT and MCNPX with different modern nuclear data library revealed that the results for the infinite multiplication factor between Monte Carlo and deterministic analysis are in good agreement ({Delta}p < 100 pcm). The differences between the results were observed to be larger for the neutron data libraries, with reactivity differences up to 350 pcm. (authors)

Girardin, G.; Alonso, M. [Ecole Polytechnique Federale de Lausanne EPFL, CH-1015 Lausanne (Switzerland); Mikityuk, K. [Paul Scherrer Institut PSI, CH-5232 Villigen-PSI (Switzerland)

2012-07-01

252

Introduction to the symposium "New frontiers from marine snakes to marine ecosystems".  

PubMed

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 might presently work with other organisms or systems, and (4) identify leading-edge topics for which studies of marine snakes might contribute uniquely to the advancement of research. PMID:22537936

Lillywhite, Harvey B; Brischoux, François

2012-08-01

253

Isotopic analysis of Bothrops atrox in Amazonian forest  

NASA Astrophysics Data System (ADS)

The poisoning of snakes is considered a public health problem, especially in populations from rural areas of tropical and subtropical countries. In Brazil, the 26,000 snakebites, 90% are of the genus Bothrops, and Bothrops atrox species predominant in the Amazon region including all the Brazilian Amazon. Research shows that using stable isotopes, we can verify the isotopic composition of tissues of animals that depend mainly on food, water ingested and inhaled gases. For this study, samples taken from Bothrops atrox (B. atrox), in forest using pitfall traps and fall ("Pitt-fall traps with drift fence"). The analyzes were performed by mass spectrometry, where the analytical error is 0.3‰ for carbon and 0.5‰ to nitrogen. The results of the forest animals are significantly different from results of animal vivarium. The average values of the tissues and venoms of snakes of the forest for carbon-13 and nitrogen-15 are: ?13C = -24.68‰ and ?15N = 14.22‰ and mean values of tissue and poisons snakes vivarium (Instituto Butantan) to carbon-13 and nitrogen-15 are ?13C = -20.47‰ and ?15N = 8.36‰, with a significantly different due to different sources of food animals. Based on all results isotopic ?13C and ?15N, we can suggest that changes as the power of the serpent, (nature and captivity), changes occur in relation to diet and environment as the means of the isotopic data are quite distinct, showing that these changes can also cause metabolic changes in the body of the animal itself and the different periods of turnover of each tissue analyzed.

Martinez, M. G.; Silva, A. M.; Chalkidis, H.; de Oliveira Júnior, R. C.; Camargo, P. B.

2012-12-01

254

Developmental sequences of squamate reptiles are taxon specific.  

PubMed

Recent studies in comparative vertebrate embryology have focused on two related questions. One concerns the existence of a phylotypic period, or indeed any period, during development in which sequence variation among taxa is constrained. The second question concerns the degree to which developmental characters exhibit a phylogenetic signal. These questions are important because they underpin attempts to understand the evolution of developmental characters and their links to adult morphology. To address these questions, we compared the sequence of developmental events spanning the so-called phylotypic period of vertebrate development in squamate reptiles (lizards and snakes), from the formation of the primary optic placode to the first appearance of scale anlagen. We used Bayesian phylogenetic ancestral state reconstruction analyses and estimates of Bayesian posterior probabilities of the rank order of developmental events to determine the level of support for phylogenetically associated variation in development. We assessed the amount of variation in event sequences by plotting the proportions of reconstructed ranks (excluding unlikely events, PP?Serpentes are distinguished by the earlier completion of torsion (rank 3) compared to acrodonts and pleurodonts (ranks 7 and 5, respectively). Clade specific sequences of developmental events mean that investigators should not extend observations on the development on particular squamate species to distantly related taxa for use in comparative studies. PMID:24074279

Andrews, Robin M; Brandley, Matthew C; Greene, Virginia W

2013-01-01

255

Transmutation Analysis of Enriched Uranium and Deep Burn High Temperature Reactors  

SciTech Connect

High temperature reactors (HTRs) have been under consideration for production of electricity, process heat, and for destruction of transuranics for decades. As part of the transmutation analysis efforts within the Fuel Cycle Research and Development (FCR&D) campaign, a need was identified for detailed discharge isotopics from HTRs for use in the VISION code. A conventional HTR using enriched uranium in UCO fuel was modeled having discharge burnup of 120 GWd/MTiHM. Also, a deep burn HTR (DB-HTR) was modeled burning transuranic (TRU)-only TRU-O2 fuel to a discharge burnup of 648 GWd/MTiHM. For each of these cases, unit cell depletion calculations were performed with SCALE/TRITON. Unit cells were used to perform this analysis using SCALE 6.1. Because of the long mean free paths (and migration lengths) of neutrons in HTRs, using a unit cell to represent a whole core can be non-trivial. The sizes of these cells were first set by using Serpent calculations to match a spectral index between unit cell and whole core domains. In the case of the DB-HTR, the unit cell which was arrived at in this way conserved the ratio of fuel to moderator found in a single block of fuel. In the conventional HTR case, a larger moderator-to-fuel ratio than that of a single block was needed to simulate the whole core spectrum. Discharge isotopics (for 500 nuclides) and one-group cross-sections (for 1022 nuclides) were delivered to the transmutation analysis team. This report provides documentation for these calculations. In addition to the discharge isotopics, one-group cross-sections were provided for the full list of 1022 nuclides tracked in the transmutation library.

Michael A. Pope

2012-07-01

256

Phylogeography of the Mekong mud snake (Enhydris subtaeniata): the biogeographic importance of dynamic river drainages and fluctuating sea levels for semiaquatic taxa in Indochina  

PubMed Central

During the Cenozoic, Southeast Asia was profoundly affected by plate tectonic events, dynamic river systems, fluctuating sea levels, shifting coastlines, and climatic variation, which have influenced the ecological and evolutionary trajectories of the Southeast Asian flora and fauna. We examined the role of these paleogeographic factors on shaping phylogeographic patterns focusing on a species of semiaquatic snake, Enhydris subtaeniata (Serpentes: Homalopsidae) using sequence data from three mitochondrial fragments (cytochrome b, ND4, and ATPase—2785 bp). We sampled E. subtaeniata from seven locations in three river drainage basins that encompassed most of this species’ range. Genetic diversities were typically low within locations but high across locations. Moreover, each location had a unique suite of haplotypes not shared among locations, and pairwise ?ST values (0.713–0.998) were highly significant between all location pairs. Relationships among phylogroups were well resolved and analysis of molecular variance (AMOVA) revealed strong geographical partitioning of genetic variance among the three river drainage basins surveyed. The genetic differences observed among the populations of E. subtaeniata were likely shaped by the Quaternary landscapes of Indochina and the Sunda Shelf. Historically, the middle and lower Mekong consisted of strongly dissected river valleys separated by low mountain ranges and much of the Sunda Shelf consisted of lowland river valleys that served to connect faunas associated with major regional rivers. It is thus likely that the contemporary genetic patterns observed among populations of E. subtaeniata are the result of their histories in a complex terrain that created abundant opportunities for genetic isolation and divergence yet also provided lowland connections across now drowned river valleys. PMID:22393504

Lukoschek, Vimoksalehi; Osterhage, Jennifer L; Karns, Daryl R; Murphy, John C; Voris, Harold K

2011-01-01

257

Molecular systematics of new world gopher, bull, and pinesnakes (Pituophis: Colubridae), a transcontinental species complex.  

PubMed

Pituophis melanoleucus (gopher, bull, and pinesnakes) is among the most widely distributed polytypic species complexes in North America, with most authors recognizing from a single transcontinental species (the melanoleucus complex, composed of 15 subspecies) to four (monotypic and polytypic) species. We used mitochondrial gene sequences from the two middle American species, P. deppei and P. lineaticollis, and from 13 subspecies from most of the range of the melanoleucus complex to test various phylogenetic hypotheses for Pituophis. Maximum parsimony and maximum likelihood methods identified the same major clades within Pituophis and indicated that two segments of the melanoleucus complex, the lodingi-melanoleucus-mugitus eastern pinesnake clade and the affinis-annectens-bimaris-catenifer-deserticola- sayi-ruthveni-vertebr alis clade from central and western United States and northern Mexico, represent divergent, allopatric lineages with no known intergradation zone. We recognize each of these two groupings as a different species. Our data also indicate that some ruthveni are more closely related to sayi than to other ruthveni. Nonetheless, ruthveni is an allopatric taxon diagnosable from its closest relatives by a combination of morphometric characters, and because it is likely that at least some of these traits are independent and genetically inherited, we interpret this as evidence that ruthveni has attained the status of independent evolutionary lineage, despite the fact that it retains strong genetic affinities with sayi. The endemic Baja Californian gopher snakes (bimaris and vertebralis) are considered by some taxonomists as a different species, P. vertebralis, but we discovered that these serpents belong to two different clades and hence we do not agree with the recognition of P. vertebralis as presently defined. In summary, we believe that three distinct species are included in the melanoleucus complex, Pituophis melanoleucus (sensu stricto), P. catenifer, and P. ruthveni, and that their recognition better represents the evolutionary diversity within this species complex. PMID:10631041

Rodríguez-Robles, J A; De Jesús-Escobar, J M

2000-01-01

258

Organization and operation of the marine ornamental fish and invertebrate export fishery in Puerto Rico.  

PubMed

This fishery was examined utilizing public records, stakeholder interviews, and operational site visits to describe the fishery for the Puerto Rico Coral Reef Advisory Committee as a first step toward development of policies for the effective management of these natural resources. The fishery is not large, including fewer than 20 licensed fishers operating primarily on the west end of the island. Only three operators export product, with the remaining fishers providing specimens to the exporters based upon customer orders. Most collection of coral reef species occurs over hard rubble zones mixed with relic reef structures and rock, or on the sides and frontal areas of active reefs. Other species are collected from among mangrove prop root zones, tidal flats, and seagrass beds. Collections are made using simple barrier and dip nets for fish and motile invertebrates such as shrimp. Invertebrates such as crabs, starfish, and sea cucumbers are commonly collected by overturning small rocks, gathering the specimens, and then replacing the rocks in their original positions. Specimens are carried to the boat and transferred to individual cup holders to maximize survival. Although statements concerning former use of chemicals to assist capture were noted, no evidence of current chemical use was observed. Specimens are held in re-circulating seawater systems onshore until collections are aggregated and shipped. The fishery strives to operate with mortality of<1%, as mortalities of>3% are described as unacceptable to customers. More than 100 fish species are collected in this fishery, but the top ten species account for >70% of the total numbers and >60% of the total value of the fishery, with a single species, Gramma loreto (Royal Gramma), comprising >40% of the numbers. More than 100 species of invertebrates are collected, but this fishery is also dominated by a handful of species, including anemones, hermit crabs, turbo snails, serpent starfish, and feather duster polychaetes. PMID:17465154

Legorel, Richard S; Hardin, Mark P; Ter-Ghazaryan, Diana

2005-05-01

259

Sun-Earth Day 2005: Ancient Observatories: Timeless Knowledge  

NASA Astrophysics Data System (ADS)

The NASA Sun-Earth Connection Education Forum (SECEF) annually promotes an event called Sun-Earth Day. For Sun-Earth Day 2005 SECEF has selected a theme called "Ancient Observatories: Timeless Knowledge. This year's Sun-Earth Day theme is your ticket to a fascinating journey through time as we explore centuries of sun watching by a great variety of cultures. From ancient solar motion tracking to modern solar activity monitoring the Sun has always occupied an important spot in mankind's quest to understand the Universe. Sun-Earth Day events usually are centered on the spring equinox around March 21, but this year there has already been a webcast from the San Francisco Exploratorium and the Native American ruins at Chaco Canyon, New Mexico on the day of winter solstice 2004. There will be another webcast on March 20 live from Chichen Itza, Mexico highlighting the solar alignment that makes a serpent appear on one of the ancient pyramids. The website http://sunearthday.nasa.gov has been developed to provide the necessary resources and opportunities for participation by scientists and educators in giving school or general public programs about Sun-Earth Day. The goal is to involve as much of the student population and the public in this event as possible and to help them understand the importance of the Sun for ancient and modern peoples. Through engaging activities available on the website, classrooms and museums can create their own event or participate in one of the opportunities we make available. Scientists, educators, amateur astronomers, and museums are invited to register on the website to receive a free packet of materials about Sun-Earth Day for use in making presentations or programs about the event. Past and future Sun-Earth Days will be discussed as well.

Thieman, J. R.; Cline, T.; Lewis, E.; Hawkins, I.; Odenwald, S.; Mayo, L.

2005-05-01

260

Phylogeography of the Mekong mud snake (Enhydris subtaeniata): the biogeographic importance of dynamic river drainages and fluctuating sea levels for semiaquatic taxa in Indochina.  

PubMed

During the Cenozoic, Southeast Asia was profoundly affected by plate tectonic events, dynamic river systems, fluctuating sea levels, shifting coastlines, and climatic variation, which have influenced the ecological and evolutionary trajectories of the Southeast Asian flora and fauna. We examined the role of these paleogeographic factors on shaping phylogeographic patterns focusing on a species of semiaquatic snake, Enhydris subtaeniata (Serpentes: Homalopsidae) using sequence data from three mitochondrial fragments (cytochrome b, ND4, and ATPase-2785 bp). We sampled E. subtaeniata from seven locations in three river drainage basins that encompassed most of this species' range. Genetic diversities were typically low within locations but high across locations. Moreover, each location had a unique suite of haplotypes not shared among locations, and pairwise ?(ST) values (0.713-0.998) were highly significant between all location pairs. Relationships among phylogroups were well resolved and analysis of molecular variance (AMOVA) revealed strong geographical partitioning of genetic variance among the three river drainage basins surveyed. The genetic differences observed among the populations of E. subtaeniata were likely shaped by the Quaternary landscapes of Indochina and the Sunda Shelf. Historically, the middle and lower Mekong consisted of strongly dissected river valleys separated by low mountain ranges and much of the Sunda Shelf consisted of lowland river valleys that served to connect faunas associated with major regional rivers. It is thus likely that the contemporary genetic patterns observed among populations of E. subtaeniata are the result of their histories in a complex terrain that created abundant opportunities for genetic isolation and divergence yet also provided lowland connections across now drowned river valleys. PMID:22393504

Lukoschek, Vimoksalehi; Osterhage, Jennifer L; Karns, Daryl R; Murphy, John C; Voris, Harold K

2011-11-01

261

Effect of the Target Motion Sampling Temperature Treatment Method on the Statistics and Performance  

NASA Astrophysics Data System (ADS)

Target Motion Sampling (TMS) is a stochastic on-the-fly temperature treatment technique that is being developed as a part of the Monte Carlo reactor physics code Serpent. The method provides for modeling of arbitrary temperatures in continuous-energy Monte Carlo tracking routines with only one set of cross sections stored in the computer memory. Previously, only the performance of the TMS method in terms of CPU time per transported neutron has been discussed. Since the effective cross sections are not calculated at any point of a transport simulation with TMS, reaction rate estimators must be scored using sampled cross sections, which is expected to increase the variances and, consequently, to decrease the figures-of-merit. This paper examines the effects of the TMS on the statistics and performance in practical calculations involving reaction rate estimation with collision estimators. Against all expectations it turned out that the usage of sampled response values has no practical effect on the performance of reaction rate estimators when using TMS with elevated basis cross section temperatures (EBT), i.e. the usual way. With 0 Kelvin cross sections a significant increase in the variances of capture rate estimators was observed right below the energy region of unresolved resonances, but at these energies the figures-of-merit could be increased using a simple resampling technique to decrease the variances of the responses. It was, however, noticed that the usage of the TMS method increases the statistical deviances of all estimators, including the flux estimator, by tens of percents in the vicinity of very strong resonances. This effect is actually not related to the usage of sampled responses, but is instead an inherent property of the TMS tracking method and concerns both EBT and 0 K calculations.

Viitanen, Tuomas; Leppänen, Jaakko

2014-06-01

262

Cross-Cultural Astronomy in Informal Education Settings - Collaboration with Integrity  

NASA Astrophysics Data System (ADS)

The richness of astronomical knowledge and traditions from diverse cultures can engage participants of all ages and backgrounds. We will present astronomy-focused programs for museums, planetariums, and community centers designed to enhance participation of underserved populations in celebrating the International Year of Astronomy (IYA) in 2009. We will share examples of how the indigenous astronomies from the Southwestern US and Mesoamerica can be juxtaposed with Western astronomy to enhance education efforts and understanding for all audiences. In these examples, the traditional knowledge has been highlighted and incorporated into the realm of innovative and unique multimedia resources that engage students and the public, and which often ignite a deeper and more authentic interest in western astronomy and astrophysics. We will discuss approaches to displaying the Navajo sky in a digital planetarium in a manner that is true to the Navajo worldview and that also presents images and information from Western astronomy. We will share multi-media resources that highlight the importance of solar alignments in architecture and in landscape within the context of the seasons. We will also discuss how we are exploring ways to protect the intellectual property rights of indigenous sky knowledge while making aspects of it available to the general public. Our collaboration upholds the integrity of both Western and Indigenous astronomy knowledge and research protocols, and honors indigenous languages. We will discuss collaborative and relationship-based evaluation strategies emerging from the above efforts and from a new effort, Cosmic Serpent, a professional development program to increase the capacity of museum practitioners to bridge indigenous and western science learning in informal settings. We will provide links and information to access products and programs to engage all audiences in the wonder, complexity, and beauty of our Universe. We acknowledge the generous support of NASA/SMD and NSF DRL/ISE.

Maryboy, Nancy; Hawkins, I.; Begay, D.; Sakimoto, P.

2008-05-01

263

[A history of Korean medical association's emblem: the caduceus of Asklepios and Hermes].  

PubMed

An emblem represents the identity of an organization. Through the emblem of an organization, they differentiate the members from others and reinforce the membership, homogeneity, and pride. It is also a tool that an organization officially publicizes its mission and values. The symbol designed by Cho, Byungduk was announced as the first emblem of Korean Medical Association (KMA) on October 31st 1947. His design work has the caduceus with the Taeguk sign on the top, the symbol of Korea, and the Red Cross in the background including the name, 'KMA'. Since then, the emblem was revised three times: in 1964, 1973, and 1995. The current symbol is based on the design of the first one. Although Asklepian, the single serpent-entwined staff of Asklepios, is the one known as the symbol of medicine, this emblem takes the caduceus of Hermes who is the patron god of merchants, thieves, and travelers. The mistake comes from the unawareness of the distinction between the caduceus of Asklepios and Hermes. Moreover, it proves that U. S. Army Medical Corps (USAMC) heavily influenced the reconstruction of Korean health care system including KMA. The USAMC has used the symbol of caduceus since 1902. In 1947, the year that the first emblem of KMA was established, Southern part of Korea was governed by the United States Military Government (USMG, 1945-1948). The current emblem of KMA brings up a question whether we should continue to use the symbol that was taken from USMAC in the historical period of USMG governance. Celebrating 100th anniversary year of KMA, KMA needs to re-evaluate the appropriateness of the KMA symbol. PMID:18175460

Shin, Young-Jeon

2007-06-01

264

Hydrogen Isotope Measurements of Organic Acids and Alcohols by Pyrolysis-GC-MS-TC-IRMS: Application to Analysis of Experimentally Derived Hydrothermal Mineral-Catalyzed Organic Products  

NASA Technical Reports Server (NTRS)

We report results of experiments to measure the H isotope composition of organic acids and alcohols. These experiments make use of a pyroprobe interfaced with a GC and high temperature extraction furnace to make quantitative H isotope measurements. This work compliments our previous work that focused on the extraction and analysis of C isotopes from the same compounds [1]. Together with our carbon isotope analyses our experiments serve as a "proof of concept" for making C and H isotope measurements on more complex mixtures of organic compounds on mineral surfaces in abiotic hydrocarbon formation processes at elevated temperatures and pressures. Our motivation for undertaking this work stems from observations of methane detected within the Martian atmosphere [2-5], coupled with evidence showing extensive water-rock interaction during Mars history [6-8]. Methane production on Mars could be the result of synthesis by mineral surface-catalyzed reduction of CO2 and/or CO by Fischer-Tropsch Type (FTT) reactions during serpentization [9,10]. Others have conducted experimental studies to show that FTT reactions are plausible mechanisms for low-molecular weight hydrocarbon formation in hydrothermal systems at mid-ocean ridges [11-13]. Our H isotope measurements utilize an analytical technique combining Pyrolysis-Gas Chromatograph-Mass Spectrometry-High Temperature Conversion-Isotope Ratio Mass Spectrometry (Py-GC-MS-TC-IRMS). This technique is designed to carry a split of the pyrolyzed GC-separated product to a Thermo DSQII quadrupole mass spectrometer as a means of making qualitative and semi-quantitative compositional measurements of separated organic compounds, therefore both chemical and isotopic measurements can be carried out simultaneously on the same sample.

Socki, Richard A.; Fu, Qi; Niles, Paul B.; Gibson, Everett K., Jr.

2012-01-01

265

Antioxidants Maintain E-Cadherin Levels to Limit Drosophila Prohemocyte Differentiation  

PubMed Central

Mitochondrial reactive oxygen species (ROS) regulate a variety of biological processes by networking with signal transduction pathways to maintain homeostasis and support adaptation to stress. In this capacity, ROS have been shown to promote the differentiation of progenitor cells, including mammalian embryonic and hematopoietic stem cells and Drosophila hematopoietic progenitors (prohemocytes). However, many questions remain about how ROS alter the regulatory machinery to promote progenitor differentiation. Here, we provide evidence for the hypothesis that ROS reduce E-cadherin levels to promote Drosophila prohemocyte differentiation. Specifically, we show that knockdown of the antioxidants, Superoxide dismutatase 2 and Catalase reduce E-cadherin protein levels prior to the loss of Odd-skipped-expressing prohemocytes. Additionally, over-expression of E-cadherin limits prohemocyte differentiation resulting from paraquat-induced oxidative stress. Furthermore, two established targets of ROS, Enhancer of Polycomb and FOS, control the level of E-cadherin protein expression. Finally, we show that knockdown of either Superoxide dismutatase 2 or Catalase leads to an increase in the E-cadherin repressor, Serpent. As a result, antioxidants and targets of ROS can control E-cadherin protein levels, and over-expression of E-cadherin can ameliorate the prohemocyte response to oxidative stress. Collectively, these data strongly suggest that ROS promote differentiation by reducing E-cadherin levels. In mammalian systems, ROS promote embryonic stem cell differentiation, whereas E-cadherin blocks differentiation. However, it is not known if elevated ROS reduce E-cadherin to promote embryonic stem cell differentiation. Thus, our findings may have identified an important mechanism by which ROS promote stem/progenitor cell differentiation. PMID:25226030

Gao, Hongjuan; Wu, Xiaorong; Simon, LaTonya; Fossett, Nancy

2014-01-01

266

STELLAR 'EGGS' EMERGE FROM MOLECULAR CLOUD (Star-Birth Clouds in M16)  

NASA Technical Reports Server (NTRS)

This eerie, dark structure, resembling an imaginary sea serpent's head, is a column of cool molecular hydrogen gas (two atoms of hydrogen in each molecule) and dust that is an incubator for new stars. The stars are embedded inside finger-like protrusions extending from the top of the nebula. Each 'fingertip' is somewhat larger than our own solar system. The pillar is slowly eroding away by the ultraviolet light from nearby hot stars, a process called 'photoevaporation'. As it does, small globules of especially dense gas buried within the cloud is uncovered. These globules have been dubbed 'EGGs' -- an acronym for 'Evaporating Gaseous Globules'. The shadows of the EGGs protect gas behind them, resulting in the finger-like structures at the top of the cloud. Forming inside at least some of the EGGs are embryonic stars -- stars that abruptly stop growing when the EGGs are uncovered and they are separated from the larger reservoir of gas from which they were drawing mass. Eventually the stars emerge, as the EGGs themselves succumb to photoevaporation. The stellar EGGS are found, appropriately enough, in the 'Eagle Nebula' (also called M16 -- the 16th object in Charles Messier's 18th century catalog of 'fuzzy' permanent objects in the sky), a nearby star-forming region 6,500 light-years away in the constellation Serpens. The picture was taken on April 1, 1995 with the Hubble Space Telescope Wide Field and Planetary Camera 2. The color image is constructed from three separate images taken in the light of emission from different types of atoms. Red shows emission from singly-ionized sulfur atoms. Green shows emission from hydrogen. Blue shows light emitted by doubly- ionized oxygen atoms. Credit: Jeff Hester and Paul Scowen (Arizona State University), and NASA Image files in GIF and JPEG format and captions may be accessed on Internet via anonymous ftp from oposite.stsci.edu in /pubinfo:

2002-01-01

267

Hubble Unveils Colorful and Turbulent Star-Birth Region on 100,000th Orbit Milestone  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site] Click on the image for orientation annotation

In commemoration of NASA's Hubble Space Telescope completing its 100,000th orbit in its 18th year of exploration and discovery, scientists at the Space Telescope Science Institute in Baltimore, Md., have aimed Hubble totake a snapshot of a dazzling region of celestial birth and renewal.

Hubble peered into a small portion of the nebula near the star cluster NGC 2074 (upper, left). The region is a firestorm of raw stellar creation, perhaps triggered by a nearby supernova explosion. It lies about 170,000 light-years away near the Tarantula nebula, one of the most active star-forming regions in our Local Group of galaxies.

The three-dimensional-looking image reveals dramatic ridges and valleys of dust, serpent-head 'pillars of creation,' and gaseous filaments glowing fiercely under torrential ultraviolet radiation. The region is on the edge of a dark molecular cloud that is an incubator for the birth of new stars.

The high-energy radiation blazing out from clusters of hot young stars already born in NGC 2074 is sculpting the wall of the nebula by slowly eroding it away. Another young cluster may be hidden beneath a circle of brilliant blue gas at center, bottom.

In this approximately 100-light-year-wide fantasy-like landscape, dark towers of dust rise above a glowing wall of gases on the surface of the molecular cloud. The seahorse-shaped pillar at lower, right is approximately 20 light-years long, roughly four times the distance between our Sun and the nearest star, Alpha Centauri.

The region is in the Large Magellanic Cloud (LMC), a satellite of our Milky Way galaxy. It is a fascinating laboratory for observing star-formation regions and their evolution. Dwarf galaxies like the LMC are considered to be the primitive building blocks of larger galaxies.

This representative color image was taken on August 10, 2008, with Hubble's Wide Field Planetary Camera 2. Red shows emission from sulfur atoms, green from glowing hydrogen, and blue from glowing oxygen.

2008-01-01

268

Deterministic Modeling of the High Temperature Test Reactor  

SciTech Connect

Idaho National Laboratory (INL) is tasked with the development of reactor physics analysis capability of the Next Generation Nuclear Power (NGNP) project. In order to examine INL’s current prismatic reactor deterministic analysis tools, the project is conducting a benchmark exercise based on modeling the High Temperature Test Reactor (HTTR). This exercise entails the development of a model for the initial criticality, a 19 column thin annular core, and the fully loaded core critical condition with 30 columns. Special emphasis is devoted to the annular core modeling, which shares more characteristics with the NGNP base design. The DRAGON code is used in this study because it offers significant ease and versatility in modeling prismatic designs. Despite some geometric limitations, the code performs quite well compared to other lattice physics codes. DRAGON can generate transport solutions via collision probability (CP), method of characteristics (MOC), and discrete ordinates (Sn). A fine group cross section library based on the SHEM 281 energy structure is used in the DRAGON calculations. HEXPEDITE is the hexagonal z full core solver used in this study and is based on the Green’s Function solution of the transverse integrated equations. In addition, two Monte Carlo (MC) based codes, MCNP5 and PSG2/SERPENT, provide benchmarking capability for the DRAGON and the nodal diffusion solver codes. The results from this study show a consistent bias of 2–3% for the core multiplication factor. This systematic error has also been observed in other HTTR benchmark efforts and is well documented in the literature. The ENDF/B VII graphite and U235 cross sections appear to be the main source of the error. The isothermal temperature coefficients calculated with the fully loaded core configuration agree well with other benchmark participants but are 40% higher than the experimental values. This discrepancy with the measurement stems from the fact that during the experiments the control rods were adjusted to maintain criticality, whereas in the model, the rod positions were fixed. In addition, this work includes a brief study of a cross section generation approach that seeks to decouple the domain in order to account for neighbor effects. This spectral interpenetration is a dominant effect in annular HTR physics. This analysis methodology should be further explored in order to reduce the error that is systematically propagated in the traditional generation of cross sections.

Ortensi, J.; Cogliati, J. J.; Pope, M. A.; Ferrer, R. M.; Ougouag, A. M.

2010-06-01

269

Snake Venom  

NSDL National Science Digital Library

The following collection of Web sites explores the properties and novel medical uses of snake venom. The first Web site (1), a ThinkQuest prizewinner, is one part of a well-crafted and informative guide to the earth's poisonous plants and animals. This particular Web page offers a good introduction to snake venom, including a table detailing the effect and concentration of the different proteins found in venom that can kill or paralyze prey. The next Web site comes from The Reptile House, a commercial breeder and supplier of reptiles and amphibians, and presents photos and facts about the ten deadliest snakes on the planet (2). A straightforward description of the three types of venomous snakes (opisthoglyphs, proteroglyphs, and solenoglyphs) and a short overview of the properties of venom is available from www.venomous.com, a privately hosted Web site (3). The next Web site comes from the online companion to the PBS Nature documentary: The Serpent's Tooth (4). The site contains an engaging article about the intrepid Bill Haast, director of the Miami Serpentarium, who "has been bitten by venomous snakes more than 160 times -- and lived to tell the tale." Howard Reinert, another snake biologist and (surprise!) snakebite victim, relates his experiences with a "dry" bite and the real thing in the next Web site from AnimalPlanet.com (5). The site also includes audio segments of experts discussing the physiological effects of snake venom and what to do if bitten by a rattlesnake. Is rattlesnake venom evolving? Research suggests that North American rattlesnake venom has become increasingly potent -- the focus of an interesting article from the American Museum of Natural History (6). The article also provides a detailed introduction to rattlesnakes and their deadly venom. Scientists around the world have been exploring the possible medicinal uses of venom, and not just for antivenin. The last two Web sites relate just some of the work being done in this area. The BBC news article recounts efforts to determine whether certain snake venoms contain chemicals that could prevent heart attacks and strokes (7). Likewise, scientists at the Howard Hughes Medical Center (8) have found a protein in snake venom that could offer a way to explore how nicotine and other drugs turn on the "pleasure centers" of the brain.

Sohmer, Rachel.

2003-01-01

270

pha-4 is Ce-fkh-1, a fork head/HNF-3alpha,beta,gamma homolog that functions in organogenesis of the C. elegans pharynx.  

PubMed

The C. elegans Ce-fkh-1 gene has been cloned on the basis of its sequence similarity to the winged-helix DNA binding domain of the Drosophila fork head and mammalian HNF-3alpha,beta,gamma genes, and mutations in the zygotically active pha-4 gene have been shown to block formation of the pharynx (and rectum) at an early stage in embryogenesis. In the present paper, we show that Ce-fkh-1 and pha-4 are the same gene. We show that PHA-4 protein is present in nuclei of essentially all pharyngeal cells, of all five cell types. PHA-4 protein first appears close to the point at which a cell lineage will produce only pharyngeal cells, independently of cell type. We show that PHA-4 binds directly to a 'pan-pharyngeal enhancer element' previously identified in the promoter of the pharyngeal myosin myo-2 gene; in transgenic embryos, ectopic PHA-4 activates ectopic myo-2 expression. We also show that ectopic PHA-4 can activate ectopic expression of the ceh-22 gene, a pharyngeal-specific NK-2-type homeodomain protein previously shown to bind a muscle-specific enhancer near the PHA-4 binding site in the myo-2 promoter. We propose that it is the combination of pha-4 and regulatory molecules such as ceh-22 that produces the specific gene expression patterns during pharynx development. Overall, pha-4 can be described as an 'organ identity factor', completely necessary for organ formation, present in all cells of the organ from the earliest stages, capable of integrating upstream developmental pathways (in this case, the two distinct pathways that produce the anterior and posterior pharynx) and participating directly in the transcriptional regulation of organ specific genes. Finally, we note that the distribution of PHA-4 protein in C. elegans embryos is remarkably similar to the distribution of the fork head protein in Drosophila embryos: high levels in the foregut/pharynx and hindgut/rectum; low levels in the gut proper. Moreover, we show that pha-4 expression in the C. elegans gut is regulated by elt-2, a C. elegans gut-specific GATA-factor and possible homolog of the Drosophila gene serpent, which influences fork head expression in the fly gut. Overall, our results provide evidence for a highly conserved pathway regulating formation of the digestive tract in all (triploblastic) metazoa. PMID:9584117

Kalb, J M; Lau, K K; Goszczynski, B; Fukushige, T; Moons, D; Okkema, P G; McGhee, J D

1998-06-01

271

Profiling the venom gland transcriptomes of Costa Rican snakes by 454 pyrosequencing  

PubMed Central

Background A long term research goal of venomics, of applied importance for improving current antivenom therapy, but also for drug discovery, is to understand the pharmacological potential of venoms. Individually or combined, proteomic and transcriptomic studies have demonstrated their feasibility to explore in depth the molecular diversity of venoms. In the absence of genome sequence, transcriptomes represent also valuable searchable databases for proteomic projects. Results The venom gland transcriptomes of 8 Costa Rican taxa from 5 genera (Crotalus, Bothrops, Atropoides, Cerrophidion, and Bothriechis) of pitvipers were investigated using high-throughput 454 pyrosequencing. 100,394 out of 330,010 masked reads produced significant hits in the available databases. 5.165,220 nucleotides (8.27%) were masked by RepeatMasker, the vast majority of which corresponding to class I (retroelements) and class II (DNA transposons) mobile elements. BLAST hits included 79,991 matches to entries of the taxonomic suborder Serpentes, of which 62,433 displayed similarity to documented venom proteins. Strong discrepancies between the transcriptome-computed and the proteome-gathered toxin compositions were obvious at first sight. Although the reasons underlaying this discrepancy are elusive, since no clear trend within or between species is apparent, the data indicate that individual mRNA species may be translationally controlled in a species-dependent manner. The minimum number of genes from each toxin family transcribed into the venom gland transcriptome of each species was calculated from multiple alignments of reads matched to a full-length reference sequence of each toxin family. Reads encoding ORF regions of Kazal-type inhibitor-like proteins were uniquely found in Bothriechis schlegelii and B. lateralis transcriptomes, suggesting a genus-specific recruitment event during the early-Middle Miocene. A transcriptome-based cladogram supports the large divergence between A. mexicanus and A. picadoi, and a closer kinship between A. mexicanus and C. godmani. Conclusions Our comparative next-generation sequencing (NGS) analysis reveals taxon-specific trends governing the formulation of the venom arsenal. Knowledge of the venom proteome provides hints on the translation efficiency of toxin-coding transcripts, contributing thereby to a more accurate interpretation of the transcriptome. The application of NGS to the analysis of snake venom transcriptomes, may represent the tool for opening the door to systems venomics. PMID:21605378

2011-01-01

272

An update review on Commiphora molmol and related species.  

PubMed

The origins of myrrh and frankincense are traced to the Arabian Peninsula. According to Herodotus (5th century BC): "Arabia is the only country which produces frankincense, myrrh, cassia, and cinnamon.., the trees bearing the frankincense are guarded by winged serpents of small size and various colors." Diodorus Siculus wrote, in the second half of the first century BC, that "all of Arabia exudes a most delicate fragrance; even the seamen passing by Arabia can smell the strong fragrance that gives health and vigor." He also mentioned gold mines so pure that no smelting was necessary. The Magi, carrying myrrh, frankincense, and gold, came from the East: Arabia. The frankincense trade route, with transport by donkeys and later by camel caravans, reached Jerusalem and Egypt from the Dhofar region of what is today Oman, through Yemen, turning north to follow the Red Sea coast. It is likely that the same or similar species of the resin-bearing plants grew across the Red Sea in the area that is now Somalia and Ethiopia, while the collection of the gum resins was initiated in Arabia. Myrrh contributed much in the human welfare. Schistosomiasis was known in ancient Egypt since remote times. Haematuria with urinary bladder disturbances was mentioned in four Papyrus papers dated back to 1950-1900 BC, and Schistosoma ova was detected in a cirrhotic liver of a mummy from 1200 BC (Ruffer, 1910). Also, Fasciola eggs were detected in a mummy (Looss, 1896). Fascioliasis infected over 17 million people worldwide causing marked morbidity and mortality (Haseeb et al., 2002). Schistosomiasis affected over 200 million people in 74 countries and territories worldwide (WHO, 1999) causing several chronic complications. Both were incriminated to predispose or accompanied human hepatitis and predisposed to HCV (Wahib et al., 2006). Most zoonotic helminthes induced immune response (Nutman, 2001) characterized by producing of type 2 cytokines, Ig G1, IgG2, IgE antibodies and eosinophil and mast cell activation (Hoffman et al., 2002). Treatment of fascioliasis required high or drug multiple doses with side effect (Farid et al., 1990). In schistosomiasis, praziquantel (PZQ) in use for > 20 years was faced with low efficacy (Leishout et al., 1998), or with increased resistance (Coles et al., 1986; Watt et al., 1988; Herrera et al., 1994; Ismail et al., 1994; 1999; Tonelli et al., 1995; Stelma et al., 1995; Fallon et al., 1997; Bennett et al., 1997; Boisier et al., 1998; Periera et al., 1998; Kusel and Hagan, 1999; Liang et al., 2000; King et al., 2000; N'Goran et al., 2003; Raso et al., 2004), potentiality of carcinogenicity, genotoxicity (Rosenkranz et al., 1995), mutagenicity (Montero et al., 1993), big dose lethality and enhanced clastogenicity of environmental pollutants (Anwar, 1994). On the other hand, Nomicos (2007) in USA reported that since antiquity, the genus Commiphora is composed of more than 200 species, and exploited as a natural drug to treat pain, skin infections, inflammatory conditions, diarrhea, and periodontal diseases. He added that in more recent history, products derived from C. myrrha and various other species of Commiphora are becoming recognized to possess significant antiseptic, anesthetic, and antitumor properties. Traditional practice and evidence-based research have supported that these properties are directly attributable to terpenoids (especially furanoses-quiterpenes), the active compounds present in myrrh essential oil. Very recently, current studies have focused on applying clinical trial methodologies to validate its use as an antineoplastic, an antiparasitic agent, and as an adjunct in healing wounds. Weeks and Simpson (2007) in USA presented the molecular phylogeny of Commiphora, a predominantly tropical African, arid-adapted tree genus to test the monophyly of its taxonomic sections and to identify clades to help direct future study of this species-rich and geographically widespread taxon. The multiple fossil calibrations of Commiphora phylogeny proved that it is sister to Vietnamese Burse

Tonkal, Abdulkader M D; Morsy, Tosson A

2008-12-01

273

Application de la methode des sous-groupes au calcul Monte-Carlo multigroupe  

NASA Astrophysics Data System (ADS)

This thesis is dedicated to the development of a Monte Carlo neutron transport solver based on the subgroup (or multiband) method. In this formalism, cross sections for resonant isotopes are represented in the form of probability tables on the whole energy spectrum. This study is intended in order to test and validate this approach in lattice physics and criticality-safety applications. The probability table method seems promising since it introduces an alternative computational way between the legacy continuous-energy representation and the multigroup method. In the first case, the amount of data invoked in continuous-energy Monte Carlo calculations can be very important and tend to slow down the overall computational time. In addition, this model preserves the quality of the physical laws present in the ENDF format. Due to its cheap computational cost, the multigroup Monte Carlo way is usually at the basis of production codes in criticality-safety studies. However, the use of a multigroup representation of the cross sections implies a preliminary calculation to take into account self-shielding effects for resonant isotopes. This is generally performed by deterministic lattice codes relying on the collision probability method. Using cross-section probability tables on the whole energy range permits to directly take into account self-shielding effects and can be employed in both lattice physics and criticality-safety calculations. Several aspects have been thoroughly studied: (1) The consistent computation of probability tables with a energy grid comprising only 295 or 361 groups. The CALENDF moment approach conducted to probability tables suitable for a Monte Carlo code. (2) The combination of the probability table sampling for the energy variable with the delta-tracking rejection technique for the space variable, and its impact on the overall efficiency of the proposed Monte Carlo algorithm. (3) The derivation of a model for taking into account anisotropic effects of the scattering reaction consistent with the subgroup method. In this study, we generalize the Discrete Angle Technique, already proposed for homogeneous, multigroup cross sections, to isotopic cross sections on the form of probability tables. In this technique, the angular density is discretized into probability tables. Similarly to the cross-section case, a moment approach is used to compute the probability tables for the scattering cosine. (4) The introduction of a leakage model based on the B1 fundamental mode approximation. Unlike deterministic lattice packages, most Monte Carlo-based lattice physics codes do not include leakage models. However the generation of homogenized and condensed group constants (cross sections, diffusion coefficients) require the critical flux. This project has involved the development of a program into the DRAGON framework, written in Fortran 2003 and wrapped with a driver in C, the GANLIB 5. Choosing Fortran 2003 has permitted the use of some modern features, such as the definition of objects and methods, data encapsulation and polymorphism. The validation of the proposed code has been performed by comparison with other numerical methods: (1) The continuous-energy Monte Carlo method of the SERPENT code. (2) The Collision Probability (CP) method and the discrete ordinates (SN) method of the DRAGON lattice code. (3) The multigroup Monte Carlo code MORET, coupled with the DRAGON code. Benchmarks used in this work are representative of some industrial configurations encountered in reactor and criticality-safety calculations: (1)Pressurized Water Reactors (PWR) cells and assemblies. (2) Canada-Deuterium Uranium Reactors (CANDU-6) clusters. (3) Critical experiments from the ICSBEP handbook (International Criticality Safety Benchmark Evaluation Program).

Martin, Nicolas

274

Latest climate changes in Romania :tornadoes  

NASA Astrophysics Data System (ADS)

Latest climate changes in Romania :tornadoes As climate change has been considered a research priority in the European Strategy for enduring development , I have done a detailed research with my students of the new climate change that has been going on in Romania for the past decade. More precisely I have studied together with my students the phenomenon of tornadoes that have seriously affected on some occasions some our our country's locations, such as Facaeni, in the county of Ialomita, in August 2002. A quite unusual phenomenon occurred on that location situated at 44.56 degrees northern latitude and at 27.89 degrees eastern longitude, that caused severe damage to the local environment and three persons lost their lives in the process, as well as other thirty people suffering from bad injuries. The magnitude of that strong phenomenon rose on the Fujita scale at level F3 which implied wing gusts between 252-300 km/ hour . A main cause of occurrence of such a severe weather was the difference in temperature of two huge air masses, one of Polar origin, and other coming from tropical latitudes . Their crossroads was on that precise territory of Romania. The duration of the worst part of the tornado path lasted only for two minutes, but the consequences of its passage were colossal : total destruction of 33 households, and other 395 were partially damaged, 1,000 people afflicted by the devastation and 100 acres of acacia tree forest ripped off the ground. The first ever recorded tornado phenomenon in Romania was around 1894-1896, considered at that time " a freak of nature" was seen as a cloud formation abnormality , an uncontrolled force of nature that had a huge impact , and at the same time, it vanished into "thin air " fast. The most affected areas in Romania by tornadoes are the south-eastern planes where the cloud formations can create fast columns of air rotating up to 500 km/hour. The local people compared the cloud funnels created on the planes to "serpents " that eat and spit out roofs, animals, trucks and concrete road poles. I have minutely searched with my students all the data of that tornado, the direction of wind gusts, we have calculated the force of the impact by studying the photos taken on that occasion. I have also done some research on other tornadoes that have taken place In Movilita and Brezoaele the past years. I have studied the increase of the centrifugal force and that of Coriolis in the context of repetition of such dangerous atmospheric phenomena that showed their apparition as ten per year in Romania. Therefore the average Coriolis parameter is 10-4 s-1, for a typical atmospheric speed of 10 m/s (22 mph) the radius is 100 km (62 mi), with a period of about 17 hours. The lowering of the air pressure occurring on such occasions has been one of my concerns as well the the speed of the cloud column rotation. All these phenomena are the effect of the climate change occurring all over our Planet due to pollution. As you can see the devastation produced by such extreme climate lead to spontaneous floods and later desertification on the south-eastern part of our country. References : 1. Craciun, Cristina, Bala, Bogdan, Tornadele din Romania, http://dezechilibrenaturale.blogspot.ro/2013/02/tornadele-din-romania.html 2. Bell, Aurora, Tornadele in Romania, http://vremea.meteoromania.ro/node/33 3. Lemon, R. Leslie, Stan-Sion, Aurora, Soci , Cornel, Corduneanu, Elena, A strong, long -track, Romanian tornado, http://www.sciencedirect.com/science/article/pii/S0169809503000632 Author : Mrs. Elena Pop, Science teacher at "Lucian Blaga" Secondary School, Ocna Mures, Romania

Pop, Elena

2014-05-01

275

Clear New View of a Classic Spiral  

NASA Astrophysics Data System (ADS)

ESO is releasing a beautiful image of the nearby galaxy Messier 83 taken by the HAWK-I instrument on ESO's Very Large Telescope (VLT) at the Paranal Observatory in Chile. The picture shows the galaxy in infrared light and demonstrates the impressive power of the camera to create one of the sharpest and most detailed pictures of Messier 83 ever taken from the ground. The galaxy Messier 83 (eso0825) is located about 15 million light-years away in the constellation of Hydra (the Sea Serpent). It spans over 40 000 light-years, only 40 percent the size of the Milky Way, but in many ways is quite similar to our home galaxy, both in its spiral shape and the presence of a bar of stars across its centre. Messier 83 is famous among astronomers for its many supernovae: vast explosions that end the lives of some stars. Over the last century, six supernovae have been observed in Messier 83 - a record number that is matched by only one other galaxy. Even without supernovae, Messier 83 is one of the brightest nearby galaxies, visible using just binoculars. Messier 83 has been observed in the infrared part of the spectrum using HAWK-I [1], a powerful camera on ESO's Very Large Telescope (VLT). When viewed in infrared light most of the obscuring dust that hides much of Messier 83 becomes transparent. The brightly lit gas around hot young stars in the spiral arms is also less prominent in infrared pictures. As a result much more of the structure of the galaxy and the vast hordes of its constituent stars can be seen. This clear view is important for astronomers looking for clusters of young stars, especially those hidden in dusty regions of the galaxy. Studying such star clusters was one of the main scientific goals of these observations [2]. When compared to earlier images, the acute vision of HAWK-I reveals far more stars within the galaxy. The combination of the huge mirror of the VLT, the large field of view and great sensitivity of the camera, and the superb observing conditions at ESO's Paranal Observatory makes HAWK-I one of the most powerful near-infrared imagers in the world. Astronomers are eagerly queuing up for the chance to use the camera, which began operation in 2007 (eso0736), and to get some of the best ground-based infrared images ever of the night sky. Notes [1] HAWK-I stands for High-Acuity Wide-field K-band Imager. More technical details about the camera can be found in an earlier press release (eso0736). [2] The data used to prepare this image were acquired by a team led by Mark Gieles (University of Cambridge) and Yuri Beletsky (ESO). Mischa Schirmer (University of Bonn) performed the challenging data processing. More information ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world's most advanced visible-light astronomical observatory and VISTA, the world's largest survey telescope. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning a 42-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become "the world's biggest eye on the sky".

2010-05-01

276

The Thousand-Ruby Galaxy  

NASA Astrophysics Data System (ADS)

ESO's Wide Field Imager has captured the intricate swirls of the spiral galaxy Messier 83, a smaller look-alike of our own Milky Way. Shining with the light of billions of stars and the ruby red glow of hydrogen gas, it is a beautiful example of a barred spiral galaxy, whose shape has led to it being nicknamed the Southern Pinwheel. Messier 83, M83 ESO PR Photo 25/08 Spiral Galaxy Messier 83 This dramatic image of the galaxy Messier 83 was captured by the Wide Field Imager at ESO's La Silla Observatory, located high in the dry desert mountains of the Chilean Atacama Desert. Messier 83 lies roughly 15 million light-years away towards the huge southern constellation of Hydra (the sea serpent). It stretches over 40 000 light-years, making it roughly 2.5 times smaller than our own Milky Way. However, in some respects, Messier 83 is quite similar to our own galaxy. Both the Milky Way and Messier 83 possess a bar across their galactic nucleus, the dense spherical conglomeration of stars seen at the centre of the galaxies. This very detailed image shows the spiral arms of Messier 83 adorned by countless bright flourishes of ruby red light. These are in fact huge clouds of glowing hydrogen gas. Ultraviolet radiation from newly born, massive stars is ionising the gas in these clouds, causing the great regions of hydrogen to glow red. These star forming regions are contrasted dramatically in this image against the ethereal glow of older yellow stars near the galaxy's central hub. The image also shows the delicate tracery of dark and winding dust streams weaving throughout the arms of the galaxy. Messier 83 was discovered by the French astronomer Nicolas Louis de Lacaille in the mid 18th century. Decades later it was listed in the famous catalogue of deep sky objects compiled by another French astronomer and famous comet hunter, Charles Messier. Recent observations of this enigmatic galaxy in ultraviolet light and radio waves have shown that even its outer desolate regions (farther out than those seen in this image) are populated with baby stars. X-ray observations of the heart of Messier 83 have shown that its centre is a hive of vigorous star formation, held deep within a cloud of superheated gas, with temperatures of 7 million degrees Celsius. Messier 83 is also one of the most prolific producers of supernovae, that is, exploding stars: this is one of the two galaxies, which had 6 supernovae in the past 100 years. One of these, SN 1957D was observable for 30 years! The Wide Field Imager (WFI) is a specialised astronomical camera attached to the 2.2-metre Max-Planck Society/ESO telescope, sited at the La Silla observatory in Chile. Located nearly 2400 m above sea level, atop the mountains of the Atacama Desert, ESO's La Silla enjoys some of the clearest and darkest skies on the whole planet, making the site ideally suited for studying the farthest depths of the Universe. To make this image, the WFI stared at M83 for roughly 100 minutes through a series of specialist filters, allowing the faint detail of the galaxy to reveal itself. The brighter stars in the foreground are stars in our own galaxy, whilst behind M83 the darkness is peppered with the faint smudges of distant galaxies.

2008-09-01

277

First Super-Earth Atmosphere Analysed  

NASA Astrophysics Data System (ADS)

The atmosphere around a super-Earth exoplanet has been analysed for the first time by an international team of astronomers using ESO's Very Large Telescope. The planet, which is known as GJ 1214b, was studied as it passed in front of its parent star and some of the starlight passed through the planet's atmosphere. We now know that the atmosphere is either mostly water in the form of steam or is dominated by thick clouds or hazes. The results will appear in the 2 December 2010 issue of the journal Nature. The planet GJ 1214b was confirmed in 2009 using the HARPS instrument on ESO's 3.6-metre telescope in Chile (eso0950) [1]. Initial findings suggested that this planet had an atmosphere, which has now been confirmed and studied in detail by an international team of astronomers, led by Jacob Bean (Harvard-Smithsonian Center for Astrophysics), using the FORS instrument on ESO's Very Large Telescope. "This is the first super-Earth to have its atmosphere analysed. We've reached a real milestone on the road toward characterising these worlds," said Bean. GJ 1214b has a radius of about 2.6 times that of the Earth and is about 6.5 times as massive, putting it squarely into the class of exoplanets known as super-Earths. Its host star lies about 40 light-years from Earth in the constellation of Ophiuchus (the Serpent Bearer). It is a faint star [2], but it is also small, which means that the size of the planet is large compared to the stellar disc, making it relatively easy to study [3]. The planet travels across the disc of its parent star once every 38 hours as it orbits at a distance of only two million kilometres: about seventy times closer than the Earth orbits the Sun. To study the atmosphere, the team observed the light coming from the star as the planet passed in front of it [4]. During these transits, some of the starlight passes through the planet's atmosphere and, depending on the chemical composition and weather on the planet, specific wavelengths of light are absorbed. The team then compared these precise new measurements with what they would expect to see for several possible atmospheric compositions. Before the new observations, astronomers had suggested three possible atmospheres for GJ 1214b. The first was the intriguing possibility that the planet was shrouded by water, which, given the close proximity to the star, would be in the form of steam. The second possibility was that this is a rocky world with an atmosphere consisting mostly of hydrogen, but with high clouds or hazes obscuring the view. The third option was that this exoplanet was like a mini-Neptune, with a small rocky core and a deep hydrogen-rich atmosphere. The new measurements do not show the telltale signs of hydrogen and hence rule out the third option. Therefore, the atmosphere is either rich in steam, or it is blanketed by clouds or hazes, similar to those seen in the atmospheres of Venus and Titan in our Solar System, which hide the signature of hydrogen.. "Although we can't yet say exactly what that atmosphere is made of, it is an exciting step forward to be able to narrow down the options for such a distant world to either steamy or hazy," says Bean. "Follow-up observations in longer wavelength infrared light are now needed to determine which of these atmospheres exists on GJ 1214b." Notes [1] The number of confirmed exoplanets reached 500 on 19 November 2010. Since then, more exoplanets have been confirmed. For the latest count, please visit: http://exoplanet.eu/catalog.php [2] If GJ 1214 were seen at the same distance from us as our Sun, it would appear 300 times fainter. [3] Because the star GJ1214 itself is quite faint - more than 100 times fainter in visible light than the host stars of the two most widely studied hot Jupiter exoplanets - the large collecting area of the Very Large Telescope was critical for acquiring enough signal for these measurements. [4] GJ 1214b's atmospheric composition was studied using the FORS instrument on the Very Large Telescope, which can perform very sensitive spectroscopy of

2010-12-01