WorldWideScience

Sample records for amphibian venoms

  1. Amphibians.

    Science.gov (United States)

    Naturescope, 1987

    1987-01-01

    Describes some of the characteristics of amphibians. Contains teaching activities ranging from a "frog sing-along" to lessons on amphibian adaptations, and night hikes to identify frog calls. Includes reproducible handouts to be used with the activities, and a quiz. (TW)

  2. Endoscopy in Amphibians.

    Science.gov (United States)

    Chai, Norin

    2015-09-01

    Despite advances in exotic animal endoscopy, descriptions involving amphibians are scarce. Amphibian endoscopy shares some similarities with reptiles, especially in lizards. Selected procedures are discussed, including stomatoscopy, gastroscopy, coelioscopy, and biopsy of coelomic organs and lesions. This short overview provides the practitioner with pragmatic advice on how to conduct safe and effective endoscopic examinations in amphibians.

  3. Tempo and Mode of the Evolution of Venom and Poison in Tetrapods

    OpenAIRE

    Harris, Richard J; Kevin Arbuckle

    2016-01-01

    Toxic weaponry in the form of venom and poison has evolved in most groups of animals, including all four major lineages of tetrapods. Moreover, the evolution of such traits has been linked to several key aspects of the biology of toxic animals including life-history and diversification. Despite this, attempts to investigate the macroevolutionary patterns underlying such weaponry are lacking. In this study we analyse patterns of venom and poison evolution across reptiles, amphibians, mammals, ...

  4. Book Review: McCranie, J.R., L.D. Wilson - G. Köhler. 2005. Amphibians and Reptiles of the Bay Islands and Cayos Cochinos, Honduras

    OpenAIRE

    Sasa, Mahmood

    2007-01-01

    During the last four years, we have witnessed the publication of several important books that summarized current knowledge on the herpetofauna of Central America: Savage's (2002) The Amphibians and Reptiles of Costa Rica, McCranie and Wilson's (2002) The Amphibians of Honduras, Campbell and Lamar's (2004) The Venomous Reptiles of the Western Hemisphere, and Solórzano's (2004) Serpientes de Costa Rica. Recently, McCranie, Wilson and Köhler inspire us with a volume on the species of amphibians ...

  5. Allergies to Insect Venom

    Science.gov (United States)

    Allergies To Insect Venom Facts About Allergies The tendency to develop allergies may be inherited. If you have allergic tendencies and ... lives of those who are sensitive to it...insect venom! Although less common than pollen allergy, insect ...

  6. HYMENOPTERA ALLERGENS: FROM VENOM TO VENOME

    Directory of Open Access Journals (Sweden)

    Edzard eSpillner

    2014-02-01

    Full Text Available In Western Europe hymenoptera venom allergy primarily relates to venoms of the honeybee and the common yellow jacket. In contrast to other allergen sources, only a few major components of hymenoptera venoms had been characterized until recently. Improved expression systems and proteomic detection strategies have allowed the identification and characterization of a wide range of additional allergens. The field of hymenoptera venom allergy research has moved rapidly from focusing on venom extract and single major allergens to a molecular understanding of the entire venome as a system of unique and characteristic components. An increasing number of such components has been identified, characterized regarding function and assessed for allergenic potential. Moreover, advanced expression strategies for recombinant production of venom allergens allow selective modification of molecules and provide insight into different types of IgE reactivities and sensitization patterns. The obtained information contributes to an increased diagnostic precision in hymenoptera venom allergy and may serve for monitoring, reevaluation and improvement of current therapeutic strategies.

  7. Surgery in Amphibians.

    Science.gov (United States)

    Chai, Norin

    2016-01-01

    Amphibian surgery has been especially described in research. Since the last decade, interest for captive amphibians has increased, so have the indications for surgical intervention. Clinicians should not hesitate to advocate such manipulations. Amphibian surgeries have no overwhelming obstacles. These patients heal well and tolerate blood loss more than higher vertebrates. Most procedures described in reptiles (mostly lizards) can be undertaken in most amphibians if equipment can be matched to the patients' size. In general, the most difficult aspect would be the provision of adequate anesthesia.

  8. Climate change and amphibians

    Directory of Open Access Journals (Sweden)

    Corn, P. S.

    2005-01-01

    Full Text Available Amphibian life histories are exceedingly sensitive to temperature and precipitation, and there is good evidence that recent climate change has already resulted in a shift to breeding earlier in the year for some species. There are also suggestions that the recent increase in the occurrence of El Niño events has caused declines of anurans in Central America and is linked to elevated mortality of amphibian embryos in the northwestern United States. However, evidence linking amphibian declines in Central America to climate relies solely on correlations, and the mechanisms underlying the declines are not understood. Connections between embryo mortality and declines in abundance have not been demonstrated. Analyses of existing data have generally failed to find a link between climate and amphibian declines. It is likely, however, that future climate change will cause further declines of some amphibian species. Reduced soil moisture could reduce prey species and eliminate habitat. Reduced snowfall and increased summer evaporation could have dramatic effects on the duration or occurrence of seasonal wetlands, which are primary habitat for many species of amphibians. Climate change may be a relatively minor cause of current amphibian declines, but it may be the biggest future challenge to the persistence of many species

  9. AMPHIBIAN POPULATION DYNAMICS

    Science.gov (United States)

    Agriculture has contributed to loss of vertebrate biodiversity in many regions, including the U.S. Corn Belt. Amphibian populations, in particular, have experienced widespread and often inexplicable declines, range reductions, and extinctions. However, few attempts have been made...

  10. Antiviral immunity in amphibians.

    Science.gov (United States)

    Chen, Guangchun; Robert, Jacques

    2011-11-01

    Although a variety of virus species can infect amphibians, diseases caused by ranaviruses ([RVs]; Iridoviridae) have become prominent, and are a major concern for biodiversity, agriculture and international trade. The relatively recent and rapid increase in prevalence of RV infections, the wide range of host species infected by RVs, the variability in host resistance among population of the same species and among different developmental stages, all suggest an important involvement of the amphibian immune system. Nevertheless, the roles of the immune system in the etiology of viral diseases in amphibians are still poorly investigated. We review here the current knowledge of antiviral immunity in amphibians, focusing on model species such as the frog Xenopus and the salamander (Ambystoma tigrinum), and on recent progress in generating tools to better understand how host immune defenses control RV infections, pathogenicity, and transmission.

  11. Inhibition of Escherichia coli ATP synthase by amphibian antimicrobial peptides

    OpenAIRE

    2010-01-01

    Previously melittin, the α-helical basic honey bee venom peptide, was shown to inhibit F1-ATPase by binding at the β-subunit DELSEED motif of F1Fo ATP synthase. Herein, we present the inhibitory effects of the basic α-helical amphibian antimicrobial peptides, ascaphin-8, aurein 2.2, aurein 2.3, carein 1.8, carein 1.9, citropin 1.1, dermaseptin, maculatin 1.1, maganin II, MRP, or XT-7, on purified F1 and membrane bound F1Fo E. coli ATP synthase. We found that the extent of inhibition by amphib...

  12. Quo Vadis Venomics? A Roadmap to Neglected Venomous Invertebrates

    Directory of Open Access Journals (Sweden)

    Bjoern Marcus von Reumont

    2014-12-01

    Full Text Available Venomics research is being revolutionized by the increased use of sensitive -omics techniques to identify venom toxins and their transcripts in both well studied and neglected venomous taxa. The study of neglected venomous taxa is necessary both for understanding the full diversity of venom systems that have evolved in the animal kingdom, and to robustly answer fundamental questions about the biology and evolution of venoms without the distorting effect that can result from the current bias introduced by some heavily studied taxa. In this review we draw the outlines of a roadmap into the diversity of poorly studied and understood venomous and putatively venomous invertebrates, which together represent tens of thousands of unique venoms. The main groups we discuss are crustaceans, flies, centipedes, non-spider and non-scorpion arachnids, annelids, molluscs, platyhelminths, nemerteans, and echinoderms. We review what is known about the morphology of the venom systems in these groups, the composition of their venoms, and the bioactivities of the venoms to provide researchers with an entry into a large and scattered literature. We conclude with a short discussion of some important methodological aspects that have come to light with the recent use of new -omics techniques in the study of venoms.

  13. Adaptive colouration in amphibians.

    Science.gov (United States)

    Rudh, Andreas; Qvarnström, Anna

    2013-01-01

    Amphibians, i.e. salamanders, frogs and caecilians show a wide range of bright colours in combination with contrasting patterns. There is variation among species, populations and also within species and populations. Furthermore, individuals often change colours during developmental stages or in response to environmental factors. This extraordinary variation means that there are excellent opportunities to test hypotheses of the adaptive significance of colours using amphibian species as models. We review the present view of functions of colouration in amphibians with the main focus on relatively unexplored topics. Variation in colouration has been found to play a role in thermoregulation, UV protection, predator avoidance and sexual signalling. However, many proposed cases of adaptive functions of colouration in amphibians remain virtually scientifically unexplored and surprisingly few genes influencing pigmentation or patterning have been detected. We would like to especially encourage more studies that take advantage of recent developments in measurement of visual properties of several possible signalling receivers (e.g. predators, competitors or mates). Future investigations on interactions between behaviour, ecology and vision have the potential to challenge our current view of the adaptive function of colouration in amphibians.

  14. Rainforest: Reptiles and Amphibians

    Science.gov (United States)

    Olson, Susanna

    2006-01-01

    Rainforest reptiles and amphibians are a vibrantly colored, multimedia art experience. To complete the entire project one may need to dedicate many class periods to production, yet in each aspect of the project a new and important skill, concept, or element is being taught or reinforced. This project incorporates the study of warm and cool color…

  15. Responding to Amphibian Loss

    NARCIS (Netherlands)

    Mendelson III, J.R.; Lips, K.R.; Gagliardo, R.W.; Rabb, G.B.; Collins, J.P.; Diffendorfer, J.E.; Daszak, P.; Ibáñez D., R.; Zippel, K.C.; Lawson, D.P.; Wright, K.M.; Stuart, S.N.; Gascon, C.; da Silva, H.R.; Burrowes, P.A.; Joglar, R.L.; La Marca, E.; Lötters, S.; du Preez, L.H.; Weldon, C.; Hyatt, A.; Rodriguez-Mahecha, J.V.; Hunt, S.; Robertson, H.; Lock, B.; Raxworthy, C.J.; Frost, D.R.; Lacy, R.C.; Alford, R.A.; Campbell, J.A.; Parra-Olea, G.; Bolaños, F.; Calvo Domingo, J.J.; Halliday, T.; Murphy, J.B.; Wake, M.H.; Coloma, L.A.; Kuzmin, S.L.; Price, M.S.; Howell, K.M.; Lau, M.; Pethiyagoda, R.; Boone, M.; Lannoo, M.J.; Blaustein, A.R.; Dobson, A.; Griffiths, R.A.; Crump, M.L.; Wake, D.B.; Brodie Jr, E.D.

    2006-01-01

    In their Policy Forum "Confronting amphibian declines and extinctions" (7 July, p. 48), J. R. Mendelson III and colleagues offer a strategy for "stopping" the widespread losses of frogs, toads, and salamanders. Disease research and captive breeding figure prominently in their call for action.

  16. Snake Venom Metalloproteinases

    Directory of Open Access Journals (Sweden)

    Gâz Florea Şerban Andrei

    2016-03-01

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

  17. Tempo and Mode of the Evolution of Venom and Poison in Tetrapods.

    Science.gov (United States)

    Harris, Richard J; Arbuckle, Kevin

    2016-06-23

    Toxic weaponry in the form of venom and poison has evolved in most groups of animals, including all four major lineages of tetrapods. Moreover, the evolution of such traits has been linked to several key aspects of the biology of toxic animals including life-history and diversification. Despite this, attempts to investigate the macroevolutionary patterns underlying such weaponry are lacking. In this study we analyse patterns of venom and poison evolution across reptiles, amphibians, mammals, and birds using a suite of phylogenetic comparative methods. We find that each major lineage has a characteristic pattern of trait evolution, but mammals and reptiles evolve under a surprisingly similar regime, whilst that of amphibians appears to be particularly distinct and highly contrasting compared to other groups. Our results also suggest that the mechanism of toxin acquisition may be an important distinction in such evolutionary patterns; the evolution of biosynthesis is far less dynamic than that of sequestration of toxins from the diet. Finally, contrary to the situation in amphibians, other tetrapod groups show an association between the evolution of toxic weaponry and higher diversification rates. Taken together, our study provides the first broad-scale analysis of macroevolutionary patterns of venom and poison throughout tetrapods.

  18. Tempo and Mode of the Evolution of Venom and Poison in Tetrapods

    Directory of Open Access Journals (Sweden)

    Richard J. Harris

    2016-06-01

    Full Text Available Toxic weaponry in the form of venom and poison has evolved in most groups of animals, including all four major lineages of tetrapods. Moreover, the evolution of such traits has been linked to several key aspects of the biology of toxic animals including life-history and diversification. Despite this, attempts to investigate the macroevolutionary patterns underlying such weaponry are lacking. In this study we analyse patterns of venom and poison evolution across reptiles, amphibians, mammals, and birds using a suite of phylogenetic comparative methods. We find that each major lineage has a characteristic pattern of trait evolution, but mammals and reptiles evolve under a surprisingly similar regime, whilst that of amphibians appears to be particularly distinct and highly contrasting compared to other groups. Our results also suggest that the mechanism of toxin acquisition may be an important distinction in such evolutionary patterns; the evolution of biosynthesis is far less dynamic than that of sequestration of toxins from the diet. Finally, contrary to the situation in amphibians, other tetrapod groups show an association between the evolution of toxic weaponry and higher diversification rates. Taken together, our study provides the first broad-scale analysis of macroevolutionary patterns of venom and poison throughout tetrapods.

  19. Tempo and Mode of the Evolution of Venom and Poison in Tetrapods

    Science.gov (United States)

    Harris, Richard J.; Arbuckle, Kevin

    2016-01-01

    Toxic weaponry in the form of venom and poison has evolved in most groups of animals, including all four major lineages of tetrapods. Moreover, the evolution of such traits has been linked to several key aspects of the biology of toxic animals including life-history and diversification. Despite this, attempts to investigate the macroevolutionary patterns underlying such weaponry are lacking. In this study we analyse patterns of venom and poison evolution across reptiles, amphibians, mammals, and birds using a suite of phylogenetic comparative methods. We find that each major lineage has a characteristic pattern of trait evolution, but mammals and reptiles evolve under a surprisingly similar regime, whilst that of amphibians appears to be particularly distinct and highly contrasting compared to other groups. Our results also suggest that the mechanism of toxin acquisition may be an important distinction in such evolutionary patterns; the evolution of biosynthesis is far less dynamic than that of sequestration of toxins from the diet. Finally, contrary to the situation in amphibians, other tetrapod groups show an association between the evolution of toxic weaponry and higher diversification rates. Taken together, our study provides the first broad-scale analysis of macroevolutionary patterns of venom and poison throughout tetrapods. PMID:27348001

  20. Field Surveys of Amphibian Populations.

    Science.gov (United States)

    Brodman, Robert

    2000-01-01

    Describes a course on amphibian research for environmental science majors. Involves students in field studies and introduces them to investigative research. Evaluates the course. (Contains 19 references.) (YDS)

  1. Toxin synergism in snake venoms

    DEFF Research Database (Denmark)

    Laustsen, Andreas Hougaard

    2016-01-01

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

  2. Scorpion venoms in gastric cancer

    Science.gov (United States)

    Zhang, Xiao-Ying; Zhang, Pei-Ying

    2016-01-01

    Venom secretions from snakes, scorpions, spiders and bees, have been widely applied in traditional medicine and current biopharmaceutical research. Possession of anticancer potential is another novel discovery for animal venoms and toxins. An increasing number of studies have shown the anticancer effects of venoms and toxins of snakes, and scorpions in vitro and in vivo, which were achieved mainly through the inhibition of cancer growth, arrest of cell cycle, induction of apoptosis and suppression of cancer metastasis. However, more evidence is needed to support this concept and the mechanisms of anticancer actions are not clearly understood. The present review is focused on the recant updates on anticancer venom research. PMID:27900054

  3. Sex determination in amphibians.

    Science.gov (United States)

    Nakamura, Masahisa

    2009-05-01

    The heterogametic sex is male in all mammals, whereas it is female in almost all birds. By contrast, there are two heterogametic types (XX/XY and ZZ/ZW) for genetic sex determination in amphibians. Though the original heterogametic sex was female in amphibians, the two heterogametic types were probably interchangeable, suggesting that sex chromosomes evolved several times in this lineage. Indeed, the frog Rana rugosa has the XX/XY and ZZ/ZW sex-determining systems within a single species, depending on the local population in Japan. The XY and ZW geographic forms with differentiated sex chromosomes probably have a common origin as undifferentiated sex chromosomes resulted from the hybridization between the primary populations of West Japan and Kanto forms. It is clear that the sex chromosomes are still undergoing evolution in this species group. Regardless of the presence of a sex-determining gene in amphibians, the gonadal sex of some species can be changed by sex steroids. Namely, sex steroids can induce the sex reversal, with estrogens inducing the male-to-female sex reversal, whereas androgens have the opposite effect. In R. rugosa, gonadal activity of CYP19 (P450 aromatase) is correlated with the feminization of gonads. Of particular interest is that high levels of CYP19 expression are observed in indifferent gonads at time before sex determination. Increases in the expression of CYP19 in female gonads and CYP17 (P450 17alpha-hydroxylase/C17-20 lyase) in male gonads suggest that the former plays an important role in phenotypic female determination, whereas the latter is needed for male determination. Thus, steroids could be the key factor for sex determination in R. rugosa. In addition to the role of sex steroids in gonadal sex determination in this species, Foxl2 and Sox3 are capable of promoting CYP19 expression. Since both the genes are autosomal, another factor up-regulating CYP19 expression must be recruited. The factor, which may be located on the X or W

  4. DNA barcoding amphibians and reptiles.

    Science.gov (United States)

    Vences, Miguel; Nagy, Zoltán T; Sonet, Gontran; Verheyen, Erik

    2012-01-01

    Only a few major research programs are currently targeting COI barcoding of amphibians and reptiles (including chelonians and crocodiles), two major groups of tetrapods. Amphibian and reptile species are typically old, strongly divergent, and contain deep conspecific lineages which might lead to problems in species assignment with incomplete reference databases. As far as known, there is no single pair of COI primers that will guarantee a sufficient rate of success across all amphibian and reptile taxa, or within major subclades of amphibians and reptiles, which means that the PCR amplification strategy needs to be adjusted depending on the specific research question. In general, many more amphibian and reptile taxa have been sequenced for 16S rDNA, which for some purposes may be a suitable complementary marker, at least until a more comprehensive COI reference database becomes available. DNA barcoding has successfully been used to identify amphibian larval stages (tadpoles) in species-rich tropical assemblages. Tissue sampling, DNA extraction, and amplification of COI is straightforward in amphibians and reptiles. Single primer pairs are likely to have a failure rate between 5 and 50% if taxa of a wide taxonomic range are targeted; in such cases the use of primer cocktails or subsequent hierarchical usage of different primer pairs is necessary. If the target group is taxonomically limited, many studies have followed a strategy of designing specific primers which then allow an easy and reliable amplification of all samples.

  5. Mitigating amphibian chytridiomycosis in nature

    Science.gov (United States)

    Garner, Trenton W. J.; Schmidt, Benedikt R.; Martel, An; Pasmans, Frank; Muths, Erin L.; Cunningham, Andrew A.; Weldon, Che; Fisher, Matthew C.; Bosch, Jaime

    2016-01-01

    Amphibians across the planet face the threat of population decline and extirpation caused by the disease chytridiomycosis. Despite consensus that the fungal pathogens responsible for the disease are conservation issues, strategies to mitigate their impacts in the natural world are, at best, nascent. Reducing risk associated with the movement of amphibians, non-amphibian vectors and other sources of infection remains the first line of defence and a primary objective when mitigating the threat of disease in wildlife. Amphibian-associated chytridiomycete fungi and chytridiomycosis are already widespread, though, and we therefore focus on discussing options for mitigating the threats once disease emergence has occurred in wild amphibian populations. All strategies have shortcomings that need to be overcome before implementation, including stronger efforts towards understanding and addressing ethical and legal considerations. Even if these issues can be dealt with, all currently available approaches, or those under discussion, are unlikely to yield the desired conservation outcome of disease mitigation. The decision process for establishing mitigation strategies requires integrated thinking that assesses disease mitigation options critically and embeds them within more comprehensive strategies for the conservation of amphibian populations, communities and ecosystems.

  6. Structural and functional analogs of the novel mammalian neuropeptide, neuromedin S (NmS), in the dermal venoms of Eurasian bombinid toads.

    Science.gov (United States)

    Chen, Tianbao; Zhou, Mei; Walker, Brian; Harriot, Pat; Mori, Kenji; Miyazato, Mikiya; Kangawa, Kenji; Shaw, Chris

    2006-06-23

    We report the isolation and structural characterization of two neuromedin S (NmS) analogs, (NmS-17 and NmS-33), from the dermal venoms of Eurasian bombinid toads. NmS is a novel neuromedin U (NmU)-related peptide with potent anorexigenic and circadian rhythm-modulating properties recently discovered in mammals. Cloning of NmS precursor-encoding cDNAs from skin venom-derived libraries revealed the presence of a high degree of transcript splice variation comparable to that found previously for NmU in both amphibian skin and mammalian brain. Synthetic replicates of both amphibian NmS peptides evoked robust and dose-dependent transient increases in intracellular calcium ion concentrations in CHO cells that had been stably transfected with either FM-3/GPR66 or FM-4/TGR-1 human NmU receptors. The potency and efficacy of these amphibian skin peptides at such receptors were comparable to those observed with human NmS and rat NmS. These data show that NmS and NmU genes had already diverged at the level of the Amphibia and that differential splicing of their transcribed mRNAs has been highly conserved throughout tetrapod vertebrate evolution indicative of fundamental biological function. NmS is additionally a novel neuropeptide homolog that can be added to the biologically active peptide arsenal of amphibian venom/defensive skin secretions.

  7. North American amphibians: distribution and diversity

    Science.gov (United States)

    : Green, David M.; Weir, Linda A.; Casper, Gary S.; Lannoo, Michael

    2014-01-01

    Some 300 species of amphibians inhabit North America. The past two decades have seen an enormous growth in interest about amphibians and an increased intensity of scientific research into their fascinating biology and continent-wide distribution. This atlas presents the spectacular diversity of North American amphibians in a geographic context. It covers all formally recognized amphibian species found in the United States and Canada, many of which are endangered or threatened with extinction. Illustrated with maps and photos, the species accounts provide current information about distribution, habitat, and conservation. Researchers, professional herpetologists, and anyone intrigued by amphibians will value North American Amphibians as a guide and reference.

  8. [Amphibian skin as a source of therapeutic peptides].

    Science.gov (United States)

    Amiche, Mohamed

    2016-01-01

    The search for new bioactive molecules that could be used in therapeutics is a major public health issue, particularly in the treatment of certain diseases such as cancer. In this context the exploration of the venom of animals (snakes, amphibians, cones, scorpions, insects...) that produce molecules of various structures and biological activities, is a very promising direction. Research in this area led to the discovery of neuropeptides, hormones, toxins, antimicrobial peptides and other extremely potent mediators. These are now used in many areas both in fundamental research and in translational research, respectively, to understand biochemical and physiological mechanisms, or to use as medical diagnostic tools and for therapeutic purposes. Pr. V. Erspamer is the first researcher to have shown, in the 1930s, that in addition to biogenic amines and alkaloids, granular glands from the skin of amphibians also produced huge amounts of peptides with various structures and biological activities. He also showed that these peptides had their counterparts, most often in the form of identical or similar peptides, in the central nervous system and the gastrointestinal tract of mammals. These observations are summarized in the form of a triangle concept of "brain-gut-skin" that states that any peptide found in a compartment should be present in the other two. In addition, abundance, ease of extraction and identification of peptides from amphibian skin make this model a means to search for their counterparts in mammals where they are present in minute quantities. This approach has two advantages: (i) at the fundamental level, the large peptide diversity, ubiquity and multiplicity of functions to which they participate, constitute a true chemical library to understand the mechanisms of recognition and signal transduction and study the physicochemical basic of the specificity; and (ii) in terms of applications, the relative simplicity of these peptides and the rise of the

  9. Privileged frameworks from snake venom.

    Science.gov (United States)

    Reeks, T A; Fry, B G; Alewood, P F

    2015-05-01

    Venom as a form of chemical prey capture is a key innovation that has underpinned the explosive radiation of the advanced snakes (Caenophidia). Small venom proteins are often rich in disulfide bonds thus facilitating stable molecular scaffolds that present key functional residues on the protein surface. New toxin types are initially developed through the venom gland over-expression of normal body proteins, their subsequent gene duplication and diversification that leads to neofunctionalisation as random mutations modify their structure and function. This process has led to preferentially selected (privileged) cysteine-rich scaffolds that enable the snake to build arrays of toxins many of which may lead to therapeutic products and research tools. This review focuses on cysteine-rich small proteins and peptides found in snake venoms spanning natriuretic peptides to phospholipase enzymes, while highlighting their three-dimensional structures and biological functions as well as their potential as therapeutic agents or research tools.

  10. Understanding Amphibian Declines Through Geographic Approaches

    Science.gov (United States)

    Gallant, Alisa

    2006-01-01

    Growing concern over worldwide amphibian declines warrants serious examination. Amphibians are important to the proper functioning of ecosystems and provide many direct benefits to humans in the form of pest and disease control, pharmaceutical compounds, and even food. Amphibians have permeable skin and rely on both aquatic and terrestrial ecosystems during different seasons and stages of their lives. Their association with these ecosystems renders them likely to serve as sensitive indicators of environmental change. While much research on amphibian declines has centered on mysterious causes, or on causes that directly affect humans (global warming, chemical pollution, ultraviolet-B radiation), most declines are the result of habitat loss and habitat alteration. Improving our ability to characterize, model, and monitor the interactions between environmental variables and amphibian habitats is key to addressing amphibian conservation. In 2000, the U.S. Geological Survey (USGS) initiated the Amphibian Research and Monitoring Initiative (ARMI) to address issues surrounding amphibian declines.

  11. Louisiana ESI: REPTILES (Reptile and Amphibian Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for reptiles and amphibians in coastal Louisiana. Vector polygons represent reptile and amphibian habitats,...

  12. BIOTIC FACTORS IN AMPHIBIAN POPULATION DECLINES

    Science.gov (United States)

    Amphibians evolved in, and continue to exist in, habitats that are replete with many other organisms. Some of these organisms serve as prey for amphibians and others interact with amphibians as predators, competitors, pathogens, or symbionts. Still other organisms in their enviro...

  13. Snake venom metalloproteinases.

    Science.gov (United States)

    Markland, Francis S; Swenson, Stephen

    2013-02-01

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

  14. Catalogue of the Type Specimens of Amphibians and Reptiles in the Herpetological Museum of the Chengdu Institute of Biology, Chinese Academy of Sciences:V. Viperidae (Reptilia, Serpentes)

    Institute of Scientific and Technical Information of China (English)

    Peng GUO; Qin LIU; Jiatang LI; Yan CAO; Yuezhao WANG

    2016-01-01

    In China, there are about 37 species of vipers belonging to 12 genera in the family Viperidae. In the Herpetological Museum of the Chengdu Institute of Biology (CIB), Chinese Academy of Sciences, the type specimens of snakes represent seven species in four genera. As a series of reports on the type specimens of Amphibians and Reptilies deposited in the Herpetological Museum of CIB, this paper focuses on the venomous snake family Viperidae in the collections at this Museum.

  15. Extraction of venom and venom gland microdissections from spiders for proteomic and transcriptomic analyses.

    Science.gov (United States)

    Garb, Jessica E

    2014-11-03

    Venoms are chemically complex secretions typically comprising numerous proteins and peptides with varied physiological activities. Functional characterization of venom proteins has important biomedical applications, including the identification of drug leads or probes for cellular receptors. Spiders are the most species rich clade of venomous organisms, but the venoms of only a few species are well-understood, in part due to the difficulty associated with collecting minute quantities of venom from small animals. This paper presents a protocol for the collection of venom from spiders using electrical stimulation, demonstrating the procedure on the Western black widow (Latrodectus hesperus). The collected venom is useful for varied downstream analyses including direct protein identification via mass spectrometry, functional assays, and stimulation of venom gene expression for transcriptomic studies. This technique has the advantage over protocols that isolate venom from whole gland homogenates, which do not separate genuine venom components from cellular proteins that are not secreted as part of the venom. Representative results demonstrate the detection of known venom peptides from the collected sample using mass spectrometry. The venom collection procedure is followed by a protocol for dissecting spider venom glands, with results demonstrating that this leads to the characterization of venom-expressed proteins and peptides at the sequence level.

  16. Ecopathology of ranaviruses infecting amphibians.

    Science.gov (United States)

    Miller, Debra; Gray, Matthew; Storfer, Andrew

    2011-11-01

    Ranaviruses are capable of infecting amphibians from at least 14 families and over 70 individual species. Ranaviruses infect multiple cell types, often culminating in organ necrosis and massive hemorrhaging. Subclinical infections have been documented, although their role in ranavirus persistence and emergence remains unclear. Water is an effective transmission medium for ranaviruses, and survival outside the host may be for significant duration. In aquatic communities, amphibians, reptiles and fish may serve as reservoirs. Controlled studies have shown that susceptibility to ranavirus infection and disease varies among amphibian species and developmental stages, and likely is impacted by host-pathogen coevolution, as well as, exogenous environmental factors. Field studies have demonstrated that the likelihood of epizootics is increased in areas of cattle grazing, where aquatic vegetation is sparse and water quality is poor. Translocation of infected amphibians through commercial trade (e.g., food, fish bait, pet industry) contributes to the spread of ranaviruses. Such introductions may be of particular concern, as several studies report that ranaviruses isolated from ranaculture, aquaculture, and bait facilities have greater virulence (i.e., ability to cause disease) than wild-type isolates. Future investigations should focus on the genetic basis for pathogen virulence and host susceptibility, ecological and anthropogenic mechanisms contributing to emergence, and vaccine development for use in captive populations and species reintroduction programs.

  17. Ecopathology of Ranaviruses Infecting Amphibians

    Directory of Open Access Journals (Sweden)

    Andrew Storfer

    2011-11-01

    Full Text Available Ranaviruses are capable of infecting amphibians from at least 14 families and over 70 individual species. Ranaviruses infect multiple cell types, often culminating in organ necrosis and massive hemorrhaging. Subclinical infections have been documented, although their role in ranavirus persistence and emergence remains unclear. Water is an effective transmission medium for ranaviruses, and survival outside the host may be for significant duration. In aquatic communities, amphibians, reptiles and fish may serve as reservoirs. Controlled studies have shown that susceptibility to ranavirus infection and disease varies among amphibian species and developmental stages, and likely is impacted by host-pathogen coevolution, as well as, exogenous environmental factors. Field studies have demonstrated that the likelihood of epizootics is increased in areas of cattle grazing, where aquatic vegetation is sparse and water quality is poor. Translocation of infected amphibians through commercial trade (e.g., food, fish bait, pet industry contributes to the spread of ranaviruses. Such introductions may be of particular concern, as several studies report that ranaviruses isolated from ranaculture, aquaculture, and bait facilities have greater virulence (i.e., ability to cause disease than wild-type isolates. Future investigations should focus on the genetic basis for pathogen virulence and host susceptibility, ecological and anthropogenic mechanisms contributing to emergence, and vaccine development for use in captive populations and species reintroduction programs.

  18. The metamorphosis of amphibian toxicogenomics

    Directory of Open Access Journals (Sweden)

    Caren eHelbing

    2012-03-01

    Full Text Available Amphibians are important vertebrates in toxicology often representing both aquatic and terrestrial forms within the life history of the same species. Of the thousands of species, only two have substantial genomics resources: the recently published genome of the Pipid, Xenopus (Silurana tropicalis, and transcript information (and ongoing genome sequencing project of Xenopus laevis. However, many more species representative of regional ecological niches and life strategies are used in toxicology worldwide. Since Xenopus species diverged from the most populous frog family, the Ranidae, ~200 million years ago, there are notable differences between them and the even more distant Caudates (salamanders and Caecilians. These differences include genome size, gene composition, and extent of polyploidization. Application of toxicogenomics to amphibians requires the mobilization of resources and expertise to develop de novo sequence assemblies and analysis strategies for a broader range of amphibian species. The present mini-review will present the advances in toxicogenomics as pertains to amphibians with particular emphasis upon the development and use of genomic techniques (inclusive of transcriptomics, proteomics, and metabolomics and the challenges inherent therein.

  19. Venomic and pharmacological activity of Acanthoscurria paulensis (Theraphosidae) spider venom.

    Science.gov (United States)

    Mourão, Caroline Barbosa F; Oliveira, Fagner Neves; e Carvalho, Andréa C; Arenas, Claudia J; Duque, Harry Morales; Gonçalves, Jacqueline C; Macêdo, Jéssica K A; Galante, Priscilla; Schwartz, Carlos A; Mortari, Márcia R; Almeida Santos, Maria de Fátima M; Schwartz, Elisabeth F

    2013-01-01

    In the present study we conducted proteomic and pharmacological characterizations of the venom extracted from the Brazilian tarantula Acanthoscurria paulensis, and evaluated the cardiotoxicity of its two main fractions. The molecular masses of the venom components were identified by mass spectrometry (MALDI-TOF-MS) after chromatographic separation (HPLC). The lethal dose (LD(50)) was determined in mice. Nociceptive behavior was evaluated by intradermal injection in mice and the edematogenic activity by the rat hind-paw assay. Cardiotoxic activity was evaluated on in situ frog heart and on isolated frog ventricle strip. From 60 chromatographic fractions, 97 distinct components were identified, with molecular masses between 601.4 and 21,932.3 Da. A trimodal molecular mass distribution was observed: 30% of the components within 500-1999 Da, 38% within 3500-5999 Da and 21% within 6500-7999 Da. The LD(50) in mice was 25.4 ± 2.4 μg/g and the effects observed were hypoactivity, anuria, constipation, dyspnea and prostration until death, which occurred at higher doses. Despite presenting a dose-dependent edematogenic activity in the rat hind-paw assay, the venom had no nociceptive activity in mice. Additionally, the venom induced a rapid blockage of electrical activity and subsequent diastolic arrest on in situ frog heart preparation, which was inhibited by pretreatment with atropine. In the electrically driven frog ventricle strip, the whole venom and its low molecular mass fraction, but not the proteic one, induced a negative inotropic effect that was also inhibited by atropine. These results suggest that despite low toxicity, A. paulensis venom can induce severe physiological disturbances in mice.

  20. Venom gland transcriptomics for identifying, cataloging, and characterizing venom proteins in snakes.

    Science.gov (United States)

    Brahma, Rajeev Kungur; McCleary, Ryan J R; Kini, R Manjunatha; Doley, Robin

    2015-01-01

    Snake venoms are cocktails of protein toxins that play important roles in capture and digestion of prey. Significant qualitative and quantitative variation in snake venom composition has been observed among and within species. Understanding these variations in protein components is instrumental in interpreting clinical symptoms during human envenomation and in searching for novel venom proteins with potential therapeutic applications. In the last decade, transcriptomic analyses of venom glands have helped in understanding the composition of various snake venoms in great detail. Here we review transcriptomic analysis as a powerful tool for understanding venom profile, variation and evolution.

  1. Amphibians as models for studying environmental change.

    Science.gov (United States)

    Hopkins, William A

    2007-01-01

    The use of amphibians as models in ecological research has a rich history. From an early foundation in studies of amphibian natural history sprang generations of scientists who used amphibians as models to address fundamental questions in population and community ecology. More recently, in the wake of an environment that human disturbances rapidly altered, ecologists have adopted amphibians as models for studying applied ecological issues such as habitat loss, pollution, disease, and global climate change. Some of the characteristics of amphibians that make them useful models for studying these environmental problems are highlighted, including their trophic importance, environmental sensitivity, research tractability, and impending extinction. The article provides specific examples from the recent literature to illustrate how studies on amphibians have been instrumental in guiding scientific thought on a broad scale. Included are examples of how amphibian research has transformed scientific disciplines, generated new theories about global health, called into question widely accepted scientific paradigms, and raised awareness in the general public that our daily actions may have widespread repercussions. In addition, studies on amphibian declines have provided insight into the complexity in which multiple independent factors may interact with one another to produce catastrophic and sometimes unpredictable effects. Because of the complexity of these problems, amphibian ecologists have been among the strongest advocates for interdisciplinary research. Future studies of amphibians will be important not only for their conservation but also for the conservation of other species, critical habitats, and entire ecosystems.

  2. Toxicity of crude and detoxified Tityus serrulatus venom in anti-venom-producing sheep

    Science.gov (United States)

    Ferreira, Marina G.; Duarte, Clara G.; Oliveira, Maira S.; Castro, Karen L. P.; Teixeira, Maílson S.; Reis, Lílian P. G.; Zambrano, José A.; Kalapothakis, Evanguedes; Michel, Ana Flávia R. M.; Soto-Blanco, Benito; Chávez-Olórtegui, Carlos

    2016-01-01

    Specific anti-venom used to treat scorpion envenomation is usually obtained from horses after hyperimmunization with crude scorpion venom. However, immunized animals often become ill because of the toxic effects of the immunogens used. This study was conducted to evaluate the toxic and immunogenic activities of crude and detoxified Tityus serrulatus (Ts) venom in sheep during the production of anti-scorpionic anti-venom. Sheep were categorized into three groups: G1, control, immunized with buffer only; G2, immunized with crude Ts venom; and G3, immunized with glutaraldehyde-detoxified Ts venom. All animals were subjected to clinical exams and supplementary tests. G2 sheep showed mild clinical changes, but the other groups tolerated the immunization program well. Specific antibodies generated in animals immunized with either Ts crude venom or glutaraldehyde-detoxified Ts venom recognized the crude Ts venom in both assays. To evaluate the lethality neutralization potential of the produced sera, individual serum samples were pre-incubated with Ts crude venom, then subcutaneously injected into mice. Efficient immune protection of 56.3% and 43.8% against Ts crude venom was observed in G2 and G3, respectively. Overall, the results of this study support the use of sheep and glutaraldehyde-detoxified Ts venom for alternative production of specific anti-venom. PMID:27297422

  3. Acutolysin C, a weak hemorrhagic toxin from the venom of Agkistrodon acutus with leucoagglutination activity

    Directory of Open Access Journals (Sweden)

    CB Wei

    2011-01-01

    Full Text Available The properties and agglutination activity of acutolysin C, a hemorrhagic metalloproteinase obtained from Agkistrodon acutus venom, were studied herein. Acutolysin C is a basic glycoprotein consisting of a single polypeptide chain with a molecular weight of 23.1 kDa and pI 8.7, containing one Zn2+ and one Ca²+ per molecule. It possesses caseinolytic, weak lethal (LD50 = 7.6 mg/kg and weak hemorrhagic (MHD = 12.0 μg activities, but does not present fibrinolytic, fibrinogenolytic, arginine esterase and phospholipase A2 actions. In addition, it revealed agglutination activity on some animal lymphocytes, including five species of mammals, six of birds, three of reptiles and one of amphibians, but had no effect on lymphocytes from two species of reptiles, one amphibian and nine species of fish. It had no effects on the erythrocytes and platelets of all 26 animal species tested. Both leucoagglutination and caseinolytic activities were inhibited by EDTA; while cysteine, 2-mercaptoethanol, 1,4-dithiothreitol, glutathione, serum against acutolysin C and serum against homologous snake venom as well as glucose, sucrose, mannose, lactose and galactose had no effects on inhibition. The lowest concentration of acutolysin C that induced mouse lymphocyte agglutination was 2.5 μg/mL. Acutolysin C is an interesting substance since it is the first member of the hemorrhagin family to be shown to have leucoagglutination activity.

  4. Colubrid Venom Composition: An -Omics Perspective

    Directory of Open Access Journals (Sweden)

    Inácio L. M. Junqueira-de-Azevedo

    2016-07-01

    Full Text Available Snake venoms have been subjected to increasingly sensitive analyses for well over 100 years, but most research has been restricted to front-fanged snakes, which actually represent a relatively small proportion of extant species of advanced snakes. Because rear-fanged snakes are a diverse and distinct radiation of the advanced snakes, understanding venom composition among “colubrids” is critical to understanding the evolution of venom among snakes. Here we review the state of knowledge concerning rear-fanged snake venom composition, emphasizing those toxins for which protein or transcript sequences are available. We have also added new transcriptome-based data on venoms of three species of rear-fanged snakes. Based on this compilation, it is apparent that several components, including cysteine-rich secretory proteins (CRiSPs, C-type lectins (CTLs, CTLs-like proteins and snake venom metalloproteinases (SVMPs, are broadly distributed among “colubrid” venoms, while others, notably three-finger toxins (3FTxs, appear nearly restricted to the Colubridae (sensu stricto. Some putative new toxins, such as snake venom matrix metalloproteinases, are in fact present in several colubrid venoms, while others are only transcribed, at lower levels. This work provides insights into the evolution of these toxin classes, but because only a small number of species have been explored, generalizations are still rather limited. It is likely that new venom protein families await discovery, particularly among those species with highly specialized diets.

  5. Colubrid Venom Composition: An -Omics Perspective

    Science.gov (United States)

    Junqueira-de-Azevedo, Inácio L. M.; Campos, Pollyanna F.; Ching, Ana T. C.; Mackessy, Stephen P.

    2016-01-01

    Snake venoms have been subjected to increasingly sensitive analyses for well over 100 years, but most research has been restricted to front-fanged snakes, which actually represent a relatively small proportion of extant species of advanced snakes. Because rear-fanged snakes are a diverse and distinct radiation of the advanced snakes, understanding venom composition among “colubrids” is critical to understanding the evolution of venom among snakes. Here we review the state of knowledge concerning rear-fanged snake venom composition, emphasizing those toxins for which protein or transcript sequences are available. We have also added new transcriptome-based data on venoms of three species of rear-fanged snakes. Based on this compilation, it is apparent that several components, including cysteine-rich secretory proteins (CRiSPs), C-type lectins (CTLs), CTLs-like proteins and snake venom metalloproteinases (SVMPs), are broadly distributed among “colubrid” venoms, while others, notably three-finger toxins (3FTxs), appear nearly restricted to the Colubridae (sensu stricto). Some putative new toxins, such as snake venom matrix metalloproteinases, are in fact present in several colubrid venoms, while others are only transcribed, at lower levels. This work provides insights into the evolution of these toxin classes, but because only a small number of species have been explored, generalizations are still rather limited. It is likely that new venom protein families await discovery, particularly among those species with highly specialized diets. PMID:27455326

  6. Endoparasites in some Swedish Amphibians

    DEFF Research Database (Denmark)

    Cedhagen, Tomas

    1988-01-01

    A study was made of the endoparasites in specimens of Rana arvalis and R. temporaria collected on two occasions from a locality of southern Sweden. Some frogs were investigated directly after capture while other frogs were kept hibernating and the composition of the parasites as well as the behav...... not previously been reported from Sweden. The late Prof. O. Nybelin's unpublished records of parasites found in Swedish amphibians are also given....

  7. Anaphylaxis to Insect Venom Allergens

    DEFF Research Database (Denmark)

    Ollert, Markus; Blank, Simon

    2015-01-01

    Anaphylaxis due to Hymenoptera stings is one of the most severe consequences of IgE-mediated hypersensitivity reactions. Although allergic reactions to Hymenoptera stings are often considered as a general model for the underlying principles of allergic disease, diagnostic tests are still hampered......, and to contribute to the understanding of the immunological mechanisms elicited by insect venoms....

  8. Survey for the amphibian chytrid Batrachochytrium dendrobatidis in Hong Kong in native amphibians and in the international amphibian trade.

    Science.gov (United States)

    Rowley, Jodi J L; Chan, Simon Kin Fung; Tang, Wing Sze; Speare, Richard; Skerratt, Lee F; Alford, Ross A; Cheung, Ka Shing; Ho, Ching Yee; Campbell, Ruth

    2007-12-13

    Chytridiomycosis, caused by the pathogen Batrachochytrium dendrobatidis, is responsible for many amphibian declines and has been identified in wild amphibian populations on all continents where they exist, except for Asia. In order to assess whether B. dendrobatidis is present on the native amphibians of Hong Kong, we sampled wild populations of Amolops hongkongensis, Paa exilispinosa, P. spinosa and Rana chloronota during 2005-2006. Amphibians infected with B. dendrobatidis have been found in the international trade, so we also examined the extent and nature of the amphibian trade in Hong Kong during 2005-2006, and assessed whether B. dendrobatidis was present in imported amphibians. All 274 individuals of 4 native amphibian species sampled tested negative for B. dendrobatidis, giving an upper 95% confidence limit for prevalence of 1.3%. Approximately 4.3 million amphibians of 45 species from 11 countries were imported into Hong Kong via air over 12 mo; we did not detect B. dendrobatidis on any of 137 imported amphibians sampled. As B. dendrobatidis generally occurs at greater than 5% prevalence in infected populations during favorable environmental conditions, native amphibians in Hong Kong appear free of B. dendrobatidis, and may be at severe risk of impact if it is introduced. Until it is established that the pathogen is present in Hong Kong, management strategies should focus on preventing it from being imported and decreasing the risk of it escaping into the wild amphibian populations if imported. Further research is needed to determine the status of B. dendrobatidis in Hong Kong with greater certainty.

  9. Amphibian haematology: Metamorphosis-related changes in blood cells

    DEFF Research Database (Denmark)

    Rosenkilde, Per; Sørensen, Inger; Ussing, Anne Phaff

    1995-01-01

    Zoofysiologi, Amphibian metamorphosis, Haematology, Immunosuppression, Immunological Tolerance, Protozoan Infection, metamorfose, springpadder, ontogenese, halepadder.......Zoofysiologi, Amphibian metamorphosis, Haematology, Immunosuppression, Immunological Tolerance, Protozoan Infection, metamorfose, springpadder, ontogenese, halepadder....

  10. Neuroendocrine-immune system interactions in amphibians: implications for understanding global amphibian declines.

    Science.gov (United States)

    Rollins-Smith, L A

    2001-01-01

    Amphibians are ancient creatures valued by biologists and naturalists around the world. They share with all other vertebrates a complex neuroendocrine system that enables them to flourish in a variety of aquatic and semiaquatic environments. Studies from a number of laboratories have demonstrated that the immune system of amphibian species is nearly as complex as that of mammals. Yet for reasons that are not well understood, amphibian species are facing greater survival challenges than in the recent past. This article will review our current understanding of the neuroendocrine immune system interactions in amphibians and address the question of whether environmental stressors may contribute to immunosuppression and amphibian declines.

  11. Amphibians at risk? Susceptibility of terrestrial amphibian life stages to pesticides.

    Science.gov (United States)

    Brühl, Carsten A; Pieper, Silvia; Weber, Brigitte

    2011-11-01

    Current pesticide risk assessment does not specifically consider amphibians. Amphibians in the aquatic environment (aquatic life stages or postmetamorphic aquatic amphibians) and terrestrial living juvenile or adult amphibians are assumed to be covered by the risk assessment for aquatic invertebrates and fish, or mammals and birds, respectively. This procedure has been evaluated as being sufficiently protective regarding the acute risk posed by a number of pesticides to aquatic amphibian life stages (eggs, larvae). However, it is unknown whether the exposure and sensitivity of terrestrial living amphibians are comparable to mammalian and avian exposure and sensitivity. We reviewed the literature on dermal pesticide absorption and toxicity studies for terrestrial life stages of amphibians, focusing on the dermal exposure pathway, that is, through treated soil or direct overspray. In vitro studies demonstrated that cutaneous absorption of chemicals is significant and that chemical percutaneous passage, P (cm/h), is higher in amphibians than in mammals. In vivo, the rapid and substantial uptake of the herbicide atrazine from treated soil by toads (Bufo americanus) has been described. Severe toxic effects on various amphibian species have been reported for field-relevant application rates of different pesticides. In general, exposure and toxicity studies for terrestrial amphibian life stages are scarce, and the reported data indicate the need for further research, especially in light of the global amphibian decline.

  12. The Biochemical Toxin Arsenal from Ant Venoms

    Directory of Open Access Journals (Sweden)

    Axel Touchard

    2016-01-01

    Full Text Available Ants (Formicidae represent a taxonomically diverse group of hymenopterans with over 13,000 extant species, the majority of which inject or spray secretions from a venom gland. The evolutionary success of ants is mostly due to their unique eusociality that has permitted them to develop complex collaborative strategies, partly involving their venom secretions, to defend their nest against predators, microbial pathogens, ant competitors, and to hunt prey. Activities of ant venom include paralytic, cytolytic, haemolytic, allergenic, pro-inflammatory, insecticidal, antimicrobial, and pain-producing pharmacologic activities, while non-toxic functions include roles in chemical communication involving trail and sex pheromones, deterrents, and aggregators. While these diverse activities in ant venoms have until now been largely understudied due to the small venom yield from ants, modern analytical and venomic techniques are beginning to reveal the diversity of toxin structure and function. As such, ant venoms are distinct from other venomous animals, not only rich in linear, dimeric and disulfide-bonded peptides and bioactive proteins, but also other volatile and non-volatile compounds such as alkaloids and hydrocarbons. The present review details the unique structures and pharmacologies of known ant venom proteinaceous and alkaloidal toxins and their potential as a source of novel bioinsecticides and therapeutic agents.

  13. Exploring the therapeutic potential of jellyfish venom.

    Science.gov (United States)

    Daly, Norelle L; Seymour, Jamie; Wilson, David

    2014-10-01

    The venom of certain jellyfish has long been known to be potentially fatal to humans, but it is only recently that details of the proteomes of these fascinating creatures are emerging. The molecular contents of the nematocysts from several jellyfish species have now been analyzed using proteomic MS approaches and include the analysis of Chironex fleckeri, one of the most venomous jellyfish known. These studies suggest that some species contain toxins related to peptides and proteins found in other venomous creatures. The detailed characterization of jellyfish venom is likely to provide insight into the diversification of toxins and might be a valuable resource in drug design.

  14. The Biochemical Toxin Arsenal from Ant Venoms.

    Science.gov (United States)

    Touchard, Axel; Aili, Samira R; Fox, Eduardo Gonçalves Paterson; Escoubas, Pierre; Orivel, Jérôme; Nicholson, Graham M; Dejean, Alain

    2016-01-20

    Ants (Formicidae) represent a taxonomically diverse group of hymenopterans with over 13,000 extant species, the majority of which inject or spray secretions from a venom gland. The evolutionary success of ants is mostly due to their unique eusociality that has permitted them to develop complex collaborative strategies, partly involving their venom secretions, to defend their nest against predators, microbial pathogens, ant competitors, and to hunt prey. Activities of ant venom include paralytic, cytolytic, haemolytic, allergenic, pro-inflammatory, insecticidal, antimicrobial, and pain-producing pharmacologic activities, while non-toxic functions include roles in chemical communication involving trail and sex pheromones, deterrents, and aggregators. While these diverse activities in ant venoms have until now been largely understudied due to the small venom yield from ants, modern analytical and venomic techniques are beginning to reveal the diversity of toxin structure and function. As such, ant venoms are distinct from other venomous animals, not only rich in linear, dimeric and disulfide-bonded peptides and bioactive proteins, but also other volatile and non-volatile compounds such as alkaloids and hydrocarbons. The present review details the unique structures and pharmacologies of known ant venom proteinaceous and alkaloidal toxins and their potential as a source of novel bioinsecticides and therapeutic agents.

  15. Peptide Toxins in Solitary Wasp Venoms

    Science.gov (United States)

    Konno, Katsuhiro; Kazuma, Kohei; Nihei, Ken-ichi

    2016-01-01

    Solitary wasps paralyze insects or spiders with stinging venom and feed the paralyzed preys to their larva. Accordingly, the venoms should contain a variety of constituents acting on nervous systems. However, only a few solitary wasp venoms have been chemically studied despite thousands of species inhabiting the planet. We have surveyed bioactive substances in solitary wasp venoms found in Japan and discovered a variety of novel bioactive peptides. Pompilidotoxins (PMTXs), in the venoms of the pompilid wasps Anoplius samariensis and Batozonellus maculifrons, are small peptides consisting of 13 amino acids without a disulfide bond. PMTXs slowed Na+ channel inactivation, in particular against neuronal type Na+ channels, and were rather selective to the Nav1.6 channel. Mastoparan-like cytolytic and antimicrobial peptides are the major components of eumenine wasp venoms. They are rich in hydrophobic and basic amino acids, adopting a α-helical secondary structure, and showing mast cell degranulating, antimicrobial and hemolytic activities. The venom of the spider wasp Cyphononyx fulvognathus contained four bradykinin-related peptides. They are hyperalgesic and, dependent on the structure, differently associated with B1 or B2 receptors. Further survey led to the isolation of leucomyosuppressin-like FMRFamide peptides from the venoms of the digger wasps Sphex argentatus and Isodontia harmandi. These results of peptide toxins in solitary wasp venoms from our studies are summarized. PMID:27096870

  16. Peptide Toxins in Solitary Wasp Venoms

    Directory of Open Access Journals (Sweden)

    Katsuhiro Konno

    2016-04-01

    Full Text Available Solitary wasps paralyze insects or spiders with stinging venom and feed the paralyzed preys to their larva. Accordingly, the venoms should contain a variety of constituents acting on nervous systems. However, only a few solitary wasp venoms have been chemically studied despite thousands of species inhabiting the planet. We have surveyed bioactive substances in solitary wasp venoms found in Japan and discovered a variety of novel bioactive peptides. Pompilidotoxins (PMTXs, in the venoms of the pompilid wasps Anoplius samariensis and Batozonellus maculifrons, are small peptides consisting of 13 amino acids without a disulfide bond. PMTXs slowed Na+ channel inactivation, in particular against neuronal type Na+ channels, and were rather selective to the Nav1.6 channel. Mastoparan-like cytolytic and antimicrobial peptides are the major components of eumenine wasp venoms. They are rich in hydrophobic and basic amino acids, adopting a α-helical secondary structure, and showing mast cell degranulating, antimicrobial and hemolytic activities. The venom of the spider wasp Cyphononyx fulvognathus contained four bradykinin-related peptides. They are hyperalgesic and, dependent on the structure, differently associated with B1 or B2 receptors. Further survey led to the isolation of leucomyosuppressin-like FMRFamide peptides from the venoms of the digger wasps Sphex argentatus and Isodontia harmandi. These results of peptide toxins in solitary wasp venoms from our studies are summarized.

  17. Cytotoxicity of Southeast Asian snake venoms

    Directory of Open Access Journals (Sweden)

    A Jamunaa

    2012-01-01

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

  18. The complexity of amphibian population declines: understanding the role of cofactors in driving amphibian losses.

    Science.gov (United States)

    Blaustein, Andrew R; Han, Barbara A; Relyea, Rick A; Johnson, Pieter T J; Buck, Julia C; Gervasi, Stephanie S; Kats, Lee B

    2011-03-01

    Population losses and extinctions of species are occurring at unprecedented rates, as exemplified by declines and extinctions of amphibians worldwide. However, studies of amphibian population declines generally do not address the complexity of the phenomenon or its implications for ecological communities, focusing instead on single factors affecting particular amphibian species. We argue that the causes for amphibian population declines are complex; may differ among species, populations, and life stages within a population; and are context dependent with multiple stressors interacting to drive declines. Because amphibians are key components of communities, we emphasize the importance of investigating amphibian declines at the community level. Selection pressures over evolutionary time have molded amphibian life history characteristics, such that they may remain static even in the face of strong, recent human-induced selection pressures.

  19. Fire and amphibians in North America

    Science.gov (United States)

    Pilliod, D.S.; Bury, R.B.; Hyde, E.J.; Pearl, C.A.; Corn, P.S.

    2003-01-01

    Information on amphibian responses to fire and fuel reduction practices is critically needed due to potential declines of species and the prevalence of new, more intensive fire management practices in North American forests. The goals of this review are to summarize the known and potential effects of fire and fuels management on amphibians and their aquatic habitats, and to identify information gaps to help direct future scientific research. Amphibians as a group are taxonomically and ecologically diverse; in turn, responses to fire and associated habitat alteration are expected to vary widely among species and among geographic regions. Available data suggest that amphibian responses to fire are spatially and temporally variable and incompletely understood. Much of the limited research has addressed short-term (1-3 years) effects of prescribed fire on terrestrial life stages of amphibians in the southeastern United States. Information on the long-term negative effects of fire on amphibians and the importance of fire for maintaining amphibian communities is sparse for the majority of taxa in North America. Given the size and severity of recent wildland fires and the national effort to reduce fuels on federal lands, future studies are needed to examine the effects of these landscape disturbances on amphibians. We encourage studies to address population-level responses of amphibians to fire by examining how different life stages are affected by changes in aquatic, riparian, and upland habitats. Research designs need to be credible and provide information that is relevant for fire managers and those responsible for assessing the potential effects of various fuel reduction alternatives on rare, sensitive, and endangered amphibian species. ?? 2003 Elsevier Science B.V. All rights reserved.

  20. Pharmacological action of Australian animal venoms.

    Science.gov (United States)

    Hodgson, W C

    1997-01-01

    1. Australia has some of the most venomous fauna in the world. Although humans are not usually perceived as being predators against these animals they are often envenomated, accidentally or otherwise. This has led to the development of antivenoms against some of the potentially lethal venoms. However, further understanding of the mechanism(s) of action of these and other venoms is important, not only for developing new treatment strategies but also in the search for novel research tools. 2. The present review discusses the pharmacology of some of the components found in venoms and outlines the research undertaken on some of Australia's venomous animals, with the exception of snakes. 3. Biogenic amines, peptides and enzymes are common venom components and produce a wide range of effects in envenomated humans. For example, respiratory failure observed after envenomation by the box jellyfish (Chirnex fleckeri) and Sydney funnel-web spider (Atrax robustus) is most likely due to potent neurotoxins in the venoms. Stonefish (Synanceja trachynis) and platypus (Ornithorhynchus anatinus) venoms, although not considered lethal, cause severe pain. However, the components responsible for these effects have not been isolated. Venom components, as yet unidentified, may be responsible for the cutaneous necrotic lesions that have been reported after some spider bites (e.g. Lampona cylindrata). Other venoms, such as those of the jumper ant (Myrmecia pilosula) and bull ant (M. pyriformis), may produce only mild skin irritation to the majority of humans but a severe anaphylactic response in sensitized victims. 4. While there has been a renewed interest in toxinology, further research is required to fully elucidate the pharmacological action of many of these venoms.

  1. Researching nature's venoms and poisons.

    Science.gov (United States)

    Warrell, David A

    2009-09-01

    Our environment hosts a vast diversity of venomous and poisonous animals and plants. Clinical toxinology is devoted to understanding, preventing and treating their effects in humans and domestic animals. In Sri Lanka, yellow oleander (Thevetia peruviana, Sinhala 'kaneru'), a widespread and accessible ornamental shrub, is a popular means of self-harm. Its toxic glycosides resemble those of foxglove, against which therapeutic antibodies have been raised. A randomised placebo-controlled trial proved that this treatment effectively reversed kaneru cardiotoxicity. There are strong scientific grounds for the use of activated charcoal, but encouraging results with multiple-dose activated charcoal were not confirmed by a recent more powerful study. Venom of Russell's viper (Daboia siamensis) in Burma (Myanmar) produces lethal effects in human victims. The case of a 17-year-old rice farmer is described with pathophysiological interpretations. During the first 9 days of hospital admission he suffered episodes of shock, coagulopathy, bleeding, acute renal failure, local tissue necrosis, generally increased capillary permeability and acute symptomatic hypoglycaemia with evidence of acute pituitary/adrenal insufficiency. Antivenom rapidly restored haemostatic function but failed to correct other effects of venom toxins incurred during the 3h before he could be treated.

  2. In-vitro diagnostics of Hymenoptera venom allergy

    NARCIS (Netherlands)

    Rueff, F.; Vos, B.; Przybilla, B.

    2013-01-01

    In-vitro diagnostics of Hymenoptera venom allergy Patients with a history of anaphylactic sting reactions require an allergological work-up (history, in-vitro tests, and skin tests) to clarify indications on venom immunotherapy and on the type of venom to be used. To demonstrate a venom sensitisatio

  3. First evidence of amphibian chytrid fungus (Batrachochytrium dendrobatidis) and ranavirus in Hong Kong amphibian trade.

    Science.gov (United States)

    Kolby, Jonathan E; Smith, Kristine M; Berger, Lee; Karesh, William B; Preston, Asa; Pessier, Allan P; Skerratt, Lee F

    2014-01-01

    The emerging infectious amphibian diseases caused by amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd) and ranaviruses are responsible for global amphibian population declines and extinctions. Although likely to have been spread by a variety of activities, transcontinental dispersal appears closely associated with the international trade in live amphibians. The territory of Hong Kong reports frequent, high volume trade in amphibians, and yet the presence of Bd and ranavirus have not previously been detected in either traded or free-ranging amphibians. In 2012, a prospective surveillance project was conducted to investigate the presence of these pathogens in commercial shipments of live amphibians exported from Hong Kong International Airport. Analysis of skin (Bd) and cloacal (ranavirus) swabs by quantitative PCR detected pathogen presence in 31/265 (11.7%) and in 105/185 (56.8%) of amphibians, respectively. In addition, the water in which animals were transported tested positive for Bd, demonstrating the risk of pathogen pollution by the disposal of untreated wastewater. It is uncertain whether Bd and ranavirus remain contained within Hong Kong's trade sector, or if native amphibians have already been exposed. Rapid response efforts are now urgently needed to determine current pathogen distribution in Hong Kong, evaluate potential trade-associated exposure to free-ranging amphibians, and identify opportunities to prevent disease establishment.

  4. First evidence of amphibian chytrid fungus (Batrachochytrium dendrobatidis and ranavirus in Hong Kong amphibian trade.

    Directory of Open Access Journals (Sweden)

    Jonathan E Kolby

    Full Text Available The emerging infectious amphibian diseases caused by amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd and ranaviruses are responsible for global amphibian population declines and extinctions. Although likely to have been spread by a variety of activities, transcontinental dispersal appears closely associated with the international trade in live amphibians. The territory of Hong Kong reports frequent, high volume trade in amphibians, and yet the presence of Bd and ranavirus have not previously been detected in either traded or free-ranging amphibians. In 2012, a prospective surveillance project was conducted to investigate the presence of these pathogens in commercial shipments of live amphibians exported from Hong Kong International Airport. Analysis of skin (Bd and cloacal (ranavirus swabs by quantitative PCR detected pathogen presence in 31/265 (11.7% and in 105/185 (56.8% of amphibians, respectively. In addition, the water in which animals were transported tested positive for Bd, demonstrating the risk of pathogen pollution by the disposal of untreated wastewater. It is uncertain whether Bd and ranavirus remain contained within Hong Kong's trade sector, or if native amphibians have already been exposed. Rapid response efforts are now urgently needed to determine current pathogen distribution in Hong Kong, evaluate potential trade-associated exposure to free-ranging amphibians, and identify opportunities to prevent disease establishment.

  5. Ossification sequence heterochrony among amphibians.

    Science.gov (United States)

    Harrington, Sean M; Harrison, Luke B; Sheil, Christopher A

    2013-01-01

    Heterochrony is an important mechanism in the evolution of amphibians. Although studies have centered on the relationship between size and shape and the rates of development, ossification sequence heterochrony also may have been important. Rigorous, phylogenetic methods for assessing sequence heterochrony are relatively new, and a comprehensive study of the relative timing of ossification of skeletal elements has not been used to identify instances of sequence heterochrony across Amphibia. In this study, a new version of the program Parsimov-based genetic inference (PGi) was used to identify shifts in ossification sequences across all extant orders of amphibians, for all major structural units of the skeleton. PGi identified a number of heterochronic sequence shifts in all analyses, the most interesting of which seem to be tied to differences in metamorphic patterns among major clades. Early ossification of the vomer, premaxilla, and dentary is retained by Apateon caducus and members of Gymnophiona and Urodela, which lack the strongly biphasic development seen in anurans. In contrast, bones associated with the jaws and face were identified as shifting late in the ancestor of Anura. The bones that do not shift late, and thereby occupy the earliest positions in the anuran cranial sequence, are those in regions of the skull that undergo the least restructuring throughout anuran metamorphosis. Additionally, within Anura, bones of the hind limb and pelvic girdle were also identified as shifting early in the sequence of ossification, which may be a result of functional constraints imposed by the drastic metamorphosis of most anurans.

  6. Sperm storage in caecilian amphibians

    Directory of Open Access Journals (Sweden)

    Kuehnel Susanne

    2012-06-01

    Full Text Available Abstract Background Female sperm storage has evolved independently multiple times among vertebrates to control reproduction in response to the environment. In internally fertilising amphibians, female salamanders store sperm in cloacal spermathecae, whereas among anurans sperm storage in oviducts is known only in tailed frogs. Facilitated through extensive field sampling following historical observations we tested for sperm storing structures in the female urogenital tract of fossorial, tropical caecilian amphibians. Findings In the oviparous Ichthyophis cf. kohtaoensis, aggregated sperm were present in a distinct region of the posterior oviduct but not in the cloaca in six out of seven vitellogenic females prior to oviposition. Spermatozoa were found most abundantly between the mucosal folds. In relation to the reproductive status decreased amounts of sperm were present in gravid females compared to pre-ovulatory females. Sperm were absent in females past oviposition. Conclusions Our findings indicate short-term oviductal sperm storage in the oviparous Ichthyophis cf. kohtaoensis. We assume that in female caecilians exhibiting high levels of parental investment sperm storage has evolved in order to optimally coordinate reproductive events and to increase fitness.

  7. Moving pieces in a venomic puzzle

    DEFF Research Database (Denmark)

    Verano-Braga, Thiago; Dutra, Alexandre A A; León, Ileana R

    2013-01-01

    Besides being a public health problem, scorpion venoms have a potential biotechnological application since they contain peptides that may be used as drug leads and/or to reveal novel pharmacological targets. A comprehensive Tityus serrulatus venom proteome study with emphasis on the phosphoproteome...

  8. Reappraisal of Vipera aspis venom neurotoxicity.

    Directory of Open Access Journals (Sweden)

    Elisabeth Ferquel

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

  9. Spider-Venom Peptides as Therapeutics

    Directory of Open Access Journals (Sweden)

    Glenn F. King

    2010-12-01

    Full Text Available Spiders are the most successful venomous animals and the most abundant terrestrial predators. Their remarkable success is due in large part to their ingenious exploitation of silk and the evolution of pharmacologically complex venoms that ensure rapid subjugation of prey. Most spider venoms are dominated by disulfide-rich peptides that typically have high affinity and specificity for particular subtypes of ion channels and receptors. Spider venoms are conservatively predicted to contain more than 10 million bioactive peptides, making them a valuable resource for drug discovery. Here we review the structure and pharmacology of spider-venom peptides that are being used as leads for the development of therapeutics against a wide range of pathophysiological conditions including cardiovascular disorders, chronic pain, inflammation, and erectile dysfunction.

  10. Pharmacological evaluation of bee venom and melittin

    Directory of Open Access Journals (Sweden)

    Camila G. Dantas

    2014-01-01

    Full Text Available The objective of this study was to identify the pharmacological effects of bee venom and its major component, melittin, on the nervous system of mice. For the pharmacological analysis, mice were treated once with saline, 0.1 or 1.2 mg/kg of bee venom and 0.1 mg/kg of melittin, subcutaneously, 30 min before being submitted to behavioral tests: locomotor activity and grooming (open-field, catalepsy, anxiety (elevated plus-maze, depression (forced swimming test and apomorphine-induced stereotypy. Haloperidol, imipramine and diazepam were administered alone (positive control or as a pre-treatment (haloperidol.The bee venom reduced motor activity and promoted cataleptic effect, in a similar manner to haloperidol.These effects were decreased by the pretreatment with haloperidol. Both melittin and bee venom decreased the apomorphine-induced stereotypies. The data indicated the antipsychotic activity of bee venom and melittin in a murine model.

  11. Spider venomics: implications for drug discovery.

    Science.gov (United States)

    Pineda, Sandy S; Undheim, Eivind A B; Rupasinghe, Darshani B; Ikonomopoulou, Maria P; King, Glenn F

    2014-10-01

    Over a period of more than 300 million years, spiders have evolved complex venoms containing an extraordinary array of toxins for prey capture and defense against predators. The major components of most spider venoms are small disulfide-bridged peptides that are highly stable and resistant to proteolytic degradation. Moreover, many of these peptides have high specificity and potency toward molecular targets of therapeutic importance. This unique combination of bioactivity and stability has made spider-venom peptides valuable both as pharmacological tools and as leads for drug development. This review describes recent advances in spider-venom-based drug discovery pipelines. We discuss spider-venom-derived peptides that are currently under investigation for treatment of a diverse range of pathologies including pain, stroke and cancer.

  12. [Bites of venomous snakes in Switzerland].

    Science.gov (United States)

    Plate, Andreas; Kupferschmidt, Hugo; Schneemann, Markus

    2016-06-08

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

  13. Pharmacological Aspects of Vipera xantina palestinae Venom

    Science.gov (United States)

    Momic, Tatjana; Arlinghaus, Franziska T.; Arien-Zakay, Hadar; Katzhendler, Jeoshua; Eble, Johannes A.; Marcinkiewicz, Cezary; Lazarovici, Philip

    2011-01-01

    In Israel, Vipera xantina palestinae (V.x.p.) is the most common venomous snake, accounting for several hundred cases of envenomation in humans and domestic animals every year, with a mortality rate of 0.5 to 2%. In this review we will briefly address the research developments relevant to our present understanding of the structure and function of V.x.p. venom with emphasis on venom disintegrins. Venom proteomics indicated the presence of four families of pharmacologically active compounds: (i) neurotoxins; (ii) hemorrhagins; (iii) angioneurin growth factors; and (iv) different types of integrin inhibitors. Viperistatin, a α1β1selective KTS disintegrin and VP12, a α2β1 selective C-type lectin were discovered. These snake venom proteins represent promising tools for research and development of novel collagen receptor selective drugs. These discoveries are also relevant for future improvement of antivenom therapy towards V.x.p. envenomation. PMID:22174978

  14. [Perspective on gravitational biology of amphibians].

    Science.gov (United States)

    Yamashita, Masamichi; Naitoh, Tomio; Wassersug, Richard J

    2002-12-01

    We review here the scientific significance of the use of amphibians for research in gravitational biology. Since amphibian eggs are quite large, yet develop rapidly and externally, it is easy to observe their development. Consequently amphibians were the first vertebrates to have their early developmental processes investigated in space. Though several deviations from normal embryonic development occur when amphibians are raised in microgravity, their developmental program is robust enough to return the organisms to an ostensibly normal morphology by the time they hatch. Evolutionally, amphibians were the first vertebrate animal to come out of the water and onto land. Subsequently they diversified and have adaptively radiated to various habitats. They now inhabit aquatic, terrestrial, arboreal and fossorial niches. This diversity can be used to help study the biological effects of gravity at the organismal level, where macroscopic phenomena are associated with gravitational loading. By choosing different amphibian models and using a comparative approach one can effectively identify the action of gravity on biological systems, and the adaptation that vertebrates have made to this loading. Advances in cellular and molecular biology provide powerful tools for the study in many fields, including gravitational biology, and amphibians have proven to be good models for studies at those levels as well. The low metabolic rates of amphibians make them convenient organisms to work with (compared to birds and mammals) in the difficult and confined spaces on orbiting research platforms. We include here a review of what is known about and the potential for further behavioral and physiological researches in space using amphibians.

  15. Chytridiomycosis: a global threat to amphibians.

    Science.gov (United States)

    Pereira, P L L; Torres, A M C; Soares, D F M; Hijosa-Valsero, M; Bécares, E

    2013-12-01

    Chytridiomycosis, which is caused by Batrachochytrium dendrobatidis, is an emerging infectious disease of amphibians. The disease is one of the main causes of the global decline in amphibians. The aetiological agent is ubiquitous, with worldwide distribution, and affects a large number of amphibian species in several biomes. In the last decade, scientific research has substantially increased knowledge of the aetiological agent and the associated infection. However, important epidemiological aspects of the environment-mediated interactions between the aetiological agent and the host are not yet clear. The objective of the present review is to describe chytridiomycosis with regard to the major features of the aetiological agent, the host and the environment.

  16. Cardiovascular physiology and diseases of amphibians.

    Science.gov (United States)

    Heinz-Taheny, Kathleen M

    2009-01-01

    The class Amphibia includes three orders of amphibians: the anurans (frogs and toads), urodeles (salamanders, axolotls, and newts), and caecilians. The diversity of lifestyles across these three orders has accompanying differences in the cardiovascular anatomy and physiology allowing for adaptations to aquatic or terrestrial habitats, pulmonic or gill respiration, hibernation, and body elongation (in the caecilian). This article provides a review of amphibian cardiovascular anatomy and physiology with discussion of unique species adaptations. In addition, amphibians as cardiovascular animal models and commonly encountered natural diseases are covered.

  17. [Venomous and poisonous animals. IV. Envenomations by venomous aquatic vertebrates].

    Science.gov (United States)

    Bédry, R; De Haro, L

    2007-04-01

    Epidemiological information on marine envenomation is generally less extensive in Europe than in tropical regions where these injuries are more severe and the need for medical advice is more frequent. For these reasons use of regional Poison Control Centers in the area where the injury occurs must be encouraged. The purpose of this review is to describe envenomation by bony fish (lion fish, stone fish, and catfish), cartilaginous fish (stingrays and poisonous sharks), or other venomous aquatic vertebrates (moray-eels and marine snakes). Understanding of these envenomation syndromes is important not only in tropical areas but also in Europe where importation of dangerous species has increased in recent years.

  18. Low cost venom extractor based on Arduino(®) board for electrical venom extraction from arthropods and other small animals.

    Science.gov (United States)

    Besson, Thomas; Debayle, Delphine; Diochot, Sylvie; Salinas, Miguel; Lingueglia, Eric

    2016-08-01

    Extracting venom from small species is usually challenging. We describe here an affordable and versatile electrical venom extractor based on the Arduino(®) Mega 2560 Board, which is designed to extract venom from arthropods and other small animals. The device includes fine tuning of stimulation time and voltage. It was used to collect venom without apparent deleterious effects, and characterized for the first time the venom of Zoropsis spinimana, a common spider in French Mediterranean regions.

  19. Report of Amphibian Development Group

    Science.gov (United States)

    Malacinski, G.

    1985-01-01

    Amphibian and fish embryos are extremely well suited for studies on pattern specification, whereas other systems (e.g., avian or mammalian) might be just as well suited for studies on differentiation or growth. Those distinctions are important for at least two reasons: (1) More precise focus regarding underlying mechanisms is called for when those distinctions are made. That facilitates the formulation of specific models or hypotheses; and (2) stress effects (i.e., the effects of weightlessness on structures (e.g., bones) which normally bear a load) are distinguished as being indirect, in contrast to direct effects of microgravity, which would be expected to act on pattern specification. That is, direct gravity effects are distinguished from indirect stress effects.

  20. Expression of venom gene homologs in diverse python tissues suggests a new model for the evolution of snake venom.

    Science.gov (United States)

    Reyes-Velasco, Jacobo; Card, Daren C; Andrew, Audra L; Shaney, Kyle J; Adams, Richard H; Schield, Drew R; Casewell, Nicholas R; Mackessy, Stephen P; Castoe, Todd A

    2015-01-01

    Snake venom gene evolution has been studied intensively over the past several decades, yet most previous studies have lacked the context of complete snake genomes and the full context of gene expression across diverse snake tissues. We took a novel approach to studying snake venom evolution by leveraging the complete genome of the Burmese python, including information from tissue-specific patterns of gene expression. We identified the orthologs of snake venom genes in the python genome, and conducted detailed analysis of gene expression of these venom homologs to identify patterns that differ between snake venom gene families and all other genes. We found that venom gene homologs in the python are expressed in many different tissues outside of oral glands, which illustrates the pitfalls of using transcriptomic data alone to define "venom toxins." We hypothesize that the python may represent an ancestral state prior to major venom development, which is supported by our finding that the expansion of venom gene families is largely restricted to highly venomous caenophidian snakes. Therefore, the python provides insight into biases in which genes were recruited for snake venom systems. Python venom homologs are generally expressed at lower levels, have higher variance among tissues, and are expressed in fewer organs compared with all other python genes. We propose a model for the evolution of snake venoms in which venom genes are recruited preferentially from genes with particular expression profile characteristics, which facilitate a nearly neutral transition toward specialized venom system expression.

  1. Evolution of Life Cycles in Early Amphibians

    Science.gov (United States)

    Schoch, Rainer R.

    2009-05-01

    Many modern amphibians have biphasic life cycles with aquatic larvae and terrestrial adults. The central questions are how and when this complicated ontogeny was established, and what is known about the lives of amphibians in the Paleozoic. Fossil evidence has accumulated that sheds light on the life histories of early amphibians, the origin of metamorphosis, and the transition to a fully terrestrial existence. The majority of early amphibians were aquatic or amphibious and underwent only gradual ontogenetic changes. Developmental plasticity played a major role in some taxa but was restricted to minor modification of ontogeny. In the Permo-Carboniferous dissorophoids, a condensation of crucial ontogenetic steps into a short phase (metamorphosis) is observed. It is likely that the origin of both metamorphosis and neoteny falls within these taxa. Fossil evidence also reveals the sequence of evolutionary changes: apparently, the ontogenetic change in feeding, not the transition to a terrestrial existence per se, made a drastic metamorphosis necessary.

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

    OpenAIRE

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

    2014-01-01

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

  3. Amphibians and Reptiles of Los Alamos County

    Energy Technology Data Exchange (ETDEWEB)

    Teralene S. Foxx; Timothy K. Haarmann; David C. Keller

    1999-10-01

    Recent studies have shown that amphibians and reptiles are good indicators of environmental health. They live in terrestrial and aquatic environments and are often the first animals to be affected by environmental change. This publication provides baseline information about amphibians and reptiles that are present on the Pajarito Plateau. Ten years of data collection and observations by researchers at Los Alamos National Laboratory, the University of New Mexico, the New Mexico Department of Game and Fish, and hobbyists are represented.

  4. Protease inhibitor in scorpion (Mesobuthus eupeus) venom prolongs the biological activities of the crude venom.

    Science.gov (United States)

    Ma, Hakim; Xiao-Peng, Tang; Yang, Shi-Long; Lu, Qiu-Min; Lai, Ren

    2016-08-01

    It is hypothesized that protease inhibitors play an essential role in survival of venomous animals through protecting peptide/protein toxins from degradation by proteases in their prey or predators. However, the biological function of protease inhibitors in scorpion venoms remains unknown. In the present study, a trypsin inhibitor was purified and characterized from the venom of scorpion Mesobuthus eupeus, which enhanced the biological activities of crude venom components in mice when injected in combination with crude venom. This protease inhibitor, named MeKTT-1, belonged to Kunitz-type toxins subfamily. Native MeKTT-1 selectively inhibited trypsin with a Kivalue of 130 nmol·L(-1). Furthermore, MeKTT-1 was shown to be a thermo-stable peptide. In animal behavioral tests, MeKTT-1 prolonged the pain behavior induced by scorpion crude venom, suggesting that protease inhibitors in scorpion venom inhibited proteases and protect the functionally important peptide/protein toxins from degradation, consequently keeping them active longer. In conclusion, this was the first experimental evidence about the natural existence of serine protease inhibitor in the venom of scorpion Mesobuthus eupeus, which preserved the activity of venom components, suggests that scorpions may use protease inhibitors for survival.

  5. Hemostatic properties of Venezuelan Bothrops snake venoms with special reference to Bothrops isabelae venom.

    Science.gov (United States)

    Rodríguez-Acosta, Alexis; Sánchez, Elda E; Márquez, Adriana; Carvajal, Zoila; Salazar, Ana M; Girón, María E; Estrella, Amalid; Gil, Amparo; Guerrero, Belsy

    2010-11-01

    In Venezuela, Bothrops snakes are responsible for more than 80% of all recorded snakebites. This study focuses on the biological and hemostatic characteristics of Bothrops isabelae venom along with its comparative characteristics with two other closely related Bothrops venoms, Bothrops atrox and Bothrops colombiensis. Electrophoretic profiles of crude B. isabelae venom showed protein bands between 14 and 100 kDa with the majority in the range of 14-31 kDa. The molecular exclusion chromatographic profile of this venom contains five fractions (F1-F5). Amidolytic activity evaluation evidenced strong thrombin-like followed by kallikrein-like activities in crude venom and in fractions F1 and F2. The fibrinogenolytic activity of B. isabelae venom at a ratio of 100:1 (fibrinogen/venom) induced a degradation of A alpha and B beta chains at 15 min and 2 h, respectively. At a ratio of 100:10, a total degradation of A alpha and B beta chains at 5 min and of gamma chains at 24 h was apparent. This current study evidences one of rarely reported for Bothrops venoms, which resembles the physiologic effect of plasmin. B. isabelae venom as well as F2 and F3 fractions, contain fibrinolytic activity on fibrin plate of 36, 23.5 and 9.45 mm(2)/microg, respectively using 25 microg of protein. Crude venom and F1 fraction showed gelatinolytic activity. Comparative analysis amongst Venezuelan bothropoid venoms, evidenced that the LD(50) of B. isabelae (5.9 mg/kg) was similar to B. atrox-Puerto Ayacucho 1 (6.1 mg/kg) and B. colombiensis-Caucagua (5.8 mg/kg). B. isabelae venom showed minor hemorrhagic activity, whereas B. atrox-Parguasa (Bolivar state) was the most hemorrhagic. In this study, a relative high thrombin-like activity was observed in B. colombiensis venoms (502-568 mUA/min/mg), and a relative high factor Xa-like activity was found in B. atrox venoms (126-294 mUA/min/mg). Fibrinolytic activity evaluated with 10 microg protein, showed that B. isabelae venom contained higher

  6. [Venomous and poisonous animals--I. Overview].

    Science.gov (United States)

    Chippaux, J P; Goyffon, M

    2006-06-01

    Venomous animals that are able to innoculate or inject venom and poisonous animals that cannot inject venom but are toxic when ingested belong to all zoological groups. They can be encountered worldwide in any ecosystem on land and at sea but they are more common and more dangerous in tropical areas. This first article of a series to appear in the next issues of Medecine Tropicale presents an overview of species involved in envenomations and poisonings. In addition to a brief reviewing geographic risks and circumstances in which bites, stings or ingestion occur, some information is provided about antivenim therapy, the only etiological treatment.

  7. Characterizing Tityus discrepans scorpion venom from a fractal perspective: Venom complexity, effects of captivity, sexual dimorphism, differences among species.

    Science.gov (United States)

    D'Suze, Gina; Sandoval, Moisés; Sevcik, Carlos

    2015-12-15

    A characteristic of venom elution patterns, shared with many other complex systems, is that many their features cannot be properly described with statistical or euclidean concepts. The understanding of such systems became possible with Mandelbrot's fractal analysis. Venom elution patterns were produced using the reversed phase high performance liquid chromatography (HPLC) with 1 mg of venom. One reason for the lack of quantitative analyses of the sources of venom variability is parametrizing the venom chromatograms' complexity. We quantize this complexity by means of an algorithm which estimates the contortedness (Q) of a waveform. Fractal analysis was used to compare venoms and to measure inter- and intra-specific venom variability. We studied variations in venom complexity derived from gender, seasonal and environmental factors, duration of captivity in the laboratory, technique used to milk venom.

  8. Ecological venomics: How genomics, transcriptomics and proteomics can shed new light on the ecology and evolution of venom.

    Science.gov (United States)

    Sunagar, Kartik; Morgenstern, David; Reitzel, Adam M; Moran, Yehu

    2016-03-01

    Animal venom is a complex cocktail of bioactive chemicals that traditionally drew interest mostly from biochemists and pharmacologists. However, in recent years the evolutionary and ecological importance of venom is realized as this trait has direct and strong influence on interactions between species. Moreover, venom content can be modulated by environmental factors. Like many other fields of biology, venom research has been revolutionized in recent years by the introduction of systems biology approaches, i.e., genomics, transcriptomics and proteomics. The employment of these methods in venom research is known as 'venomics'. In this review we describe the history and recent advancements of venomics and discuss how they are employed in studying venom in general and in particular in the context of evolutionary ecology. We also discuss the pitfalls and challenges of venomics and what the future may hold for this emerging scientific field.

  9. An examination of amphibian sensitivity to environmental contaminants: are amphibians poor canaries?

    Science.gov (United States)

    Kerby, Jacob L; Richards-Hrdlicka, Kathryn L; Storfer, Andrew; Skelly, David K

    2010-01-01

    Nearly two decades ago, the global biodiversity crisis was catapulted to the front pages of newspapers with the recognition of worldwide amphibian declines. Amphibians earned their appellation, 'canaries in a coal mine', because of apparent high sensitivity to human-mediated environmental change. The most frequently cited causes for high susceptibility include permeable skin, a dual aquatic-terrestrial life cycle and a relatively rudimentary immune system. While some researchers have questioned the basis for the canary assertion, there has been no systematic evaluation of amphibian sensitivity to environmental challenges relative to other taxa. Here, we apply a database representing thousands of toxicity tests to compare the responses of amphibians relative to that of other taxonomic groups. The use of standardized methods combined with large numbers of identical challenges enables a particularly powerful test of relative effect size. Overall, we found that amphibians only exhibit moderate relative responses to water-borne toxins. Our findings imply that, as far as chemical contaminants are concerned, amphibians are not particularly sensitive and might more aptly be described as 'miners in a coal mine'. To the extent that amphibian declines have been mediated by chemical contaminants, our findings suggest that population losses and extinctions may have already occurred in a variety of taxa much more sensitive than amphibians.

  10. Extreme diversity of scorpion venom peptides and proteins revealed by transcriptomic analysis: implication for proteome evolution of scorpion venom arsenal.

    Science.gov (United States)

    Ma, Yibao; He, Yawen; Zhao, Ruiming; Wu, Yingliang; Li, Wenxin; Cao, Zhijian

    2012-02-16

    Venom is an important genetic development crucial to the survival of scorpions for over 400 million years. We studied the evolution of the scorpion venom arsenal by means of comparative transcriptome analysis of venom glands and phylogenetic analysis of shared types of venom peptides and proteins between buthids and euscorpiids. Fifteen types of venom peptides and proteins were sequenced during the venom gland transcriptome analyses of two Buthidae species (Lychas mucronatus and Isometrus maculatus) and one Euscorpiidae species (Scorpiops margerisonae). Great diversity has been observed in translated amino acid sequences of these transcripts for venom peptides and proteins. Seven types of venom peptides and proteins were shared between buthids and euscorpiids. Molecular phylogenetic analysis revealed that at least five of the seven common types of venom peptides and proteins were likely recruited into the scorpion venom proteome before the lineage split between Buthidae and Euscorpiidae with their corresponding genes undergoing individual or multiple gene duplication events. These are α-KTxs, βKSPNs (β-KTxs and scorpines), anionic peptides, La1-like peptides, and SPSVs (serine proteases from scorpion venom). Multiple types of venom peptides and proteins were demonstrated to be continuously recruited into the venom proteome during the evolution process of individual scorpion lineages. Our results provide an insight into the recruitment pattern of the scorpion venom arsenal for the first time.

  11. Echidna venom gland transcriptome provides insights into the evolution of monotreme venom.

    Directory of Open Access Journals (Sweden)

    Emily S W Wong

    Full Text Available Monotremes (echidna and platypus are egg-laying mammals. One of their most unique characteristic is that males have venom/crural glands that are seasonally active. Male platypuses produce venom during the breeding season, delivered via spurs, to aid in competition against other males. Echidnas are not able to erect their spurs, but a milky secretion is produced by the gland during the breeding season. The function and molecular composition of echidna venom is as yet unknown. Hence, we compared the deeply sequenced transcriptome of an in-season echidna crural gland to that of a platypus and searched for putative venom genes to provide clues into the function of echidna venom and the evolutionary history of monotreme venom. We found that the echidna venom gland transcriptome was markedly different from the platypus with no correlation between the top 50 most highly expressed genes. Four peptides found in the venom of the platypus were detected in the echidna transcriptome. However, these genes were not highly expressed in echidna, suggesting that they are the remnants of the evolutionary history of the ancestral venom gland. Gene ontology terms associated with the top 100 most highly expressed genes in echidna, showed functional terms associated with steroidal and fatty acid production, suggesting that echidna "venom" may play a role in scent communication during the breeding season. The loss of the ability to erect the spur and other unknown evolutionary forces acting in the echidna lineage resulted in the gradual decay of venom components and the evolution of a new role for the crural gland.

  12. Countryside biogeography of Neotropical reptiles and amphibians.

    Science.gov (United States)

    Mendenhall, Chase D; Frishkoff, Luke O; Santos-Barrera, Georgina; Pacheco, Jesús; Mesfun, Eyobed; Mendoza Quijano, Fernando; Ehrlich, Paul R; Ceballos, Gerardo; Daily, Gretchen C; Pringle, Robert M

    2014-04-01

    The future of biodiversity and ecosystem services depends largely on the capacity of human-dominated ecosystems to support them, yet this capacity remains largely unknown. Using the framework of countryside biogeography, and working in the Las Cruces system of Coto Brus, Costa Rica, we assessed reptile and amphibian assemblages within four habitats that typify much of the Neotropics: sun coffee plantations (12 sites), pasture (12 sites), remnant forest elements (12 sites), and a larger, contiguous protected forest (3 sites in one forest). Through analysis of 1678 captures of 67 species, we draw four primary conclusions. First, we found that the majority of reptile (60%) and amphibian (70%) species in this study used an array of habitat types, including coffee plantations and actively grazed pastures. Second, we found that coffee plantations and pastures hosted rich, albeit different and less dense, reptile and amphibian biodiversity relative to the 326-ha Las Cruces Forest Reserve and neighboring forest elements. Third, we found that the small ribbons of "countryside forest elements" weaving through farmland collectively increased the effective size of a 326-ha local forest reserve 16-fold for reptiles and 14-fold for amphibians within our 236-km2 study area. Therefore, countryside forest elements, often too small for most remote sensing techniques to identify, are contributing -95% of the available habitat for forest-dependent reptiles and amphibians in our largely human-dominated study region. Fourth, we found large and pond-reproducing amphibians to prefer human-made habitats, whereas small, stream-reproducing, and directly developing species are more dependent on forest elements. Our investigation demonstrates that tropical farming landscapes can support substantial reptile and amphibian biodiversity. Our approach provides a framework for estimating the conservation value of the complex working landscapes that constitute roughly half of the global land surface

  13. Snake oil and venoms for medical research

    Science.gov (United States)

    Wolpert, H. D.

    2011-04-01

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

  14. On the venom system of centipedes (Chilopoda), a neglected group of venomous animals.

    Science.gov (United States)

    Undheim, Eivind A B; King, Glenn F

    2011-03-15

    Centipedes are among the oldest extant terrestrial arthropods and are an ecologically important group of soil and leaf litter predators. Despite their abundance and frequent, often painful, encounters with humans, little is known about the venom and venom apparatus of centipedes, although it is apparent that these are both quite different from other venomous lineages. The venom gland can be regarded as an invaginated cuticle and epidermis, consisting of numerous epithelial secretory units each with its own unique valve-like excretory system. The venom contains several different enzymes, but is strikingly different to most other arthropods in that metalloproteases appear to be important. Myotoxic, cardiotoxic, and neurotoxic activities have been described, most of which have been attributed to high molecular weight proteins. Neurotoxic activities are also unusual in that G-protein coupled receptors often seem to be involved, either directly as targets of neurotoxins or indirectly by activating endogenous agonists. These relatively slow responses may be complemented by the rapid effects caused by histamines present in the venom and from endogenous release of histamines induced by venom cytotoxins. The differences probably reflect the ancient and independent evolutionary history of the centipede venom system, although they may also be somewhat exaggerated by the paucity of information available on this largely neglected group.

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

    Science.gov (United States)

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

    2014-01-01

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

  16. Venom components from Citharischius crawshayi spider (Family Theraphosidae): exploring transcriptome, venomics, and function.

    Science.gov (United States)

    Diego-García, Elia; Peigneur, Steve; Waelkens, Etienne; Debaveye, Sarah; Tytgat, Jan

    2010-08-01

    Despite strong efforts, knowledge about the composition of the venom of many spider species remains very limited. This work is the first report of transcriptome and venom analysis of the African spider Citharischius crawshayi. We used combined protocols of transcriptomics, venomics, and biological assays to characterize the venom and genes expressed in venom glands. A cDNA library of the venom glands was constructed and used to generate expressed sequence tags (ESTs). Sequence comparisons from 236 ESTs revealed interesting and unique sequences, corresponding to toxin-like and other components. Mass spectrometrical analysis of venom fractions showed more than 600 molecular masses, some of which showed toxic activity on crickets and modulated sodium currents in DmNa(v)1 and Na(v)1.6 channels as expressed in Xenopus oocytes. Taken together, our results may contribute to a better understanding of the cellular processes involved in the transcriptome and help us to discover new components from spider venom glands with therapeutic potential.

  17. Amphibians do not follow Bergmann's rule.

    Science.gov (United States)

    Adams, Dean C; Church, James O

    2008-02-01

    The tendency for organisms to be larger in cooler climates (Bergmann's rule) is widely observed in endotherms, and has been reputed to apply to some ectotherms including amphibians. However, recent reports provide conflicting support for the pattern, questioning whether Bergmann's clines are generally present in amphibians. In this study, we measured 96,996 adult Plethodon from 3974 populations to test for the presence of Bergmann's clines in these salamanders. Only three Plethodon species exhibited a significant negative correlation between body size and temperature consistent with Bergmann's rule, whereas 37 of 40 species did not display a pattern consistent with this prediction. Further, a phylogenetic comparative analysis found no relationship between body size and temperature among species. A meta-analysis combining our data with the available data for other amphibian species revealed no support for Bergmann's rule at the genus (Plethodon), order (Caudata), or class (Amphibia) levels. Our findings strongly suggest that negative thermal body size clines are not common in amphibians, and we conclude that Bergmann's rule is not generally applicable to these taxa. Thus, evolutionary explanations of Bergmann's clines in other tetrapods need not account for unique life-history attributes of amphibians.

  18. Amphibians used in research and teaching.

    Science.gov (United States)

    O'Rourke, Dorcas P

    2007-01-01

    Amphibians have long been utilized in scientific research and in education. Historically, investigators have accumulated a wealth of information on the natural history and biology of amphibians, and this body of information is continually expanding as researchers describe new species and study the behaviors of these animals. Amphibians evolved as models for a variety of developmental and physiological processes, largely due to their unique ability to undergo metamorphosis. Scientists have used amphibian embryos to evaluate the effects of toxins, mutagens, and teratogens. Likewise, the animals are invaluable in research due to the ability of some species to regenerate limbs. Certain species of amphibians have short generation times and genetic constructs that make them desirable for transgenic and knockout technology, and there is a current national focus on developing these species for genetic and genomic research. This group of vertebrates is also critically important in the investigation of the inter-relationship of humans and the environment based on their sensitivity to climatic and habitat changes and environmental contamination.

  19. A study of bacterial contamination of rattlesnake venom

    Directory of Open Access Journals (Sweden)

    E. Garcia-Lima

    1987-03-01

    Full Text Available The authors studied the bacterial contamination of rattlesnake venom isolated from snakes in captivity and wild snakes caught recently. The captive snakes showed a relatively high incidence of bacterial contamination of their venom.

  20. Venom and cnidome ontogeny of the cubomedusae Chironex fleckeri.

    Science.gov (United States)

    McClounan, S; Seymour, J

    2012-12-15

    This is the first study to explore venom and cnidome variation of individual cubomedusae, Chironex fleckeri, of different ages and from different regional locations in relation to feeding ecology. As medusae matured the proportion of mastigophores (those nematocysts containing the lethal venom component) in the cnidome increased, along with proportion of the vertebrate toxic fraction, in the venom profile. This switch in cnidome and venom occurred at the seven to ten tentacle stage. Whole venom was found to be toxic specifically to vertebrate cardiac cells, as opposed to vertebrate skeletal cells, and dose dependent, along with the vertebrate toxic fraction. The venom and cnidome ontogeny, along with venom toxicity, is correlated with C. fleckeri's known feeding ecology. Large and mature C. fleckeri feed predominantly on vertebrates, and have a greater proportion of mastigophores in their cnidome along with more vertebrate toxic fraction in their venom, compared to when they are young and small feeding on invertebrates.

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

    Directory of Open Access Journals (Sweden)

    H. Moussatché

    1989-01-01

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

  2. Distortion product otoacoustic emissions in the amphibian ear

    NARCIS (Netherlands)

    Van Dijk, Pim; Meenderink, Sebastiaan W. F.; Nuttal, AL

    2006-01-01

    By comparing the range of emission frequencies with that of neural characteristic frequencies of the amphibian and basilar papillae, the emission generation site may be inferred. Spontaneous otoacoustic emissions in the amphibian car seem to originate from the amphibian papilla. In contrast, distort

  3. Microbiota and mucosal immunity in amphibians

    Directory of Open Access Journals (Sweden)

    Bruno M Colombo

    2015-03-01

    Full Text Available We know that animals live in a world dominated by bacteria. In the last twenty years we have learned that microbes are essential regulators of mucosal immunity. Bacterias, archeas and viruses influence different aspects of mucosal development and function. Yet the literature mainly covers findings obtained in mammals. In this review, we focus on two major themes that emerge from the comparative analysis of mammals and amphibians. These themes concern: i the structure and functions of lymphoid organs and immune cells in amphibians, with a focus on the gut mucosal immune system; and ii the characteristics of the amphibian microbiota and its influence on mucosal immunity. Lastly, we propose to use Xenopus tadpoles as an alternative small animal model to improve the fundamental knowledge on immunological functions of gut microbiota.

  4. Diversity and distribution of amphibians in Romania

    Directory of Open Access Journals (Sweden)

    Dan Cogălniceanu

    2013-04-01

    Full Text Available Nineteen species of amphibians inhabit Romania, 9 of which reach their range limit on this territory. Based on published occurrence reports, museum collections and our own data we compiled a national database of amphibian occurrences. We georeferenced 26779 amphibian species occurrences, and performed an analysis of their spatial patterns, checking for hotspots and patterns of species richness. The results of spatial statistic analyses supported the idea of a biased sampling for Romania, with clear hotspots of increased sampling efforts. The sampling effort is biased towards species with high detectability, protected areas, and large cities. Future sampling efforts should be focused mostly on species with a high rarity score in order to accurately map their range. Our results are an important step in achieving the long-term goals of increasing the efficiency of conservation efforts and evaluating the species range shifts under climate change scenarios.

  5. Biological Scaling Problems and Solutions in Amphibians.

    Science.gov (United States)

    Levy, Daniel L; Heald, Rebecca

    2015-08-10

    Size is a primary feature of biological systems that varies at many levels, from the organism to its constituent cells and subcellular structures. Amphibians populate some of the extremes in biological size and have provided insight into scaling mechanisms, upper and lower size limits, and their physiological significance. Body size variation is a widespread evolutionary tactic among amphibians, with miniaturization frequently correlating with direct development that occurs without a tadpole stage. The large genomes of salamanders lead to large cell sizes that necessitate developmental modification and morphological simplification. Amphibian extremes at the cellular level have provided insight into mechanisms that accommodate cell-size differences. Finally, how organelles scale to cell size between species and during development has been investigated at the molecular level, because subcellular scaling can be recapitulated using Xenopus in vitro systems.

  6. Amphibian monitoring in the Atchafalaya Basin

    Science.gov (United States)

    Waddle, Hardin

    2011-01-01

    Amphibians are a diverse group of animals that includes frogs, toads, and salamanders. They are adapted to living in a variety of habitats, but most require water for at least one life stage. Amphibians have recently become a worldwide conservation concern because of declines and extinctions even in remote protected areas previously thought to be safe from the pressures of habitat loss and degradation. Amphibians are an important part of ecosystem dynamics because they can be quite abundant and serve both as a predator of smaller organisms and as prey to a suite of vertebrate predators. Their permeable skin and aquatic life history also make them useful as indicators of ecosystem health. Since 2002, the U.S. Geological Survey has been studying the frog and toad species inhabiting the Atchafalaya Basin to monitor for population declines and to better understand how the species are potentially affected by disease, environmental contaminants, and climate change.

  7. Microbiota and mucosal immunity in amphibians.

    Science.gov (United States)

    Colombo, Bruno M; Scalvenzi, Thibault; Benlamara, Sarah; Pollet, Nicolas

    2015-01-01

    We know that animals live in a world dominated by bacteria. In the last 20 years, we have learned that microbes are essential regulators of mucosal immunity. Bacteria, archeas, and viruses influence different aspects of mucosal development and function. Yet, the literature mainly covers findings obtained in mammals. In this review, we focus on two major themes that emerge from the comparative analysis of mammals and amphibians. These themes concern: (i) the structure and functions of lymphoid organs and immune cells in amphibians, with a focus on the gut mucosal immune system; and (ii) the characteristics of the amphibian microbiota and its influence on mucosal immunity. Lastly, we propose to use Xenopus tadpoles as an alternative small-animal model to improve the fundamental knowledge on immunological functions of gut microbiota.

  8. Effects of Roads on Amphibian Populations

    DEFF Research Database (Denmark)

    Hels, T.

    to have experienced the wonders of early summer sunrises in the field - and the joy of thawing out frozen fingers after hours of field work around freezing point. Amphibian populations are declining. This worrying fact is what has initiated this work. Some fifty years ago, the life history of frogs...... is the result of my three year PhD study at the National Environmental Research Institute, Kalø, and University of Copenhagen. Funded by NERI, the Danish Research Academy, and the Danish Road Directorate, it has dealt mainly with the effects of traffic and roads on amphibian populations. The Spadefoot toad...... of Spadefoot toads (Pelobates fuscus Laur.) II The effect of road kills on amphibian populations III Simulating viability of a Spadefoot toad (P. fuscus) metapopulation in a landscape fragmented by a road The manuscripts are preceded by a synopsis which sums up the work and puts it into a broader perspective...

  9. Where to look when identifying roadkilled amphibians?

    Directory of Open Access Journals (Sweden)

    Marc Franch

    2015-12-01

    Full Text Available Roads have multiple effects on wildlife; amphibians are one of the groups more intensely affected by roadkills. Monitoring roadkills is expensive and time consuming. Automated mapping systems for detecting roadkills, based on robotic computer vision techniques, are largely necessary. Amphibians can be recognised by a set of features as shape, size, colouration, habitat and location. This species identification by using multiple features at the same time is known as “jizz”. In a similar way to human vision, computer vision algorithms must incorporate a prioritisation process when analysing the objects in an image. Our main goal here was to give a numerical priority sequence of particular characteristics of roadkilled amphibians to improve the computing and learning process of algorithms. We asked hundred and five amateur and professional herpetologists to answer a simple test of five sets with ten images each of roadkilled amphibians, in order to determine which body parts or characteristics (body form, colour, and other patterns are used to identify correctly the species. Anura was the group most easily identified when it was roadkilled and Caudata was the most difficult. The lower the taxonomic level of amphibian, the higher the difficulty of identifying them, both in Anura and Caudata. Roadkilled amphibians in general and Anura group were mostly identified by the Form, by the combination of Form and Colour, and finally by Colour. Caudata was identified mainly on Form and Colour and on Colour. Computer vision algorithms must incorporate these combinations of features, avoiding to work exclusively in one specific feature.

  10. [Evolution of brain development in amphibians].

    Science.gov (United States)

    Savel'ev, S V

    2009-01-01

    Principal events in the early embryonic development of the nervous system, from neurulation to primary differentiation, are considered in different amphibian species. Attention is paid to numerous interspecific differences in the structure of neuroepithelium and the patterns of neurulation and embryonic brain segmentation. The data presented indicate that similarity in brain developmental patterns is apparently explained by universality of morphogenetic mechanisms rather than by the common origin of particular species. A hypothesis is proposed that similarity in the shape of the developing amphibian brain is determined by mechanisms of coding positional information necessary for histogenetic differentiation.

  11. Amphibians as model to study endocrine disrupters.

    Science.gov (United States)

    Kloas, Werner; Lutz, Ilka

    2006-10-13

    Environmental compounds can interfere with endocrine systems of wildlife and humans. These so-called endocrine disrupters (ED) are known to affect reproductive biology and thyroid system. The classical model species for these endocrine systems are amphibians and therefore they can serve as sentinels for detection of the modes of action (MOAs) of ED. Recently, amphibians are being reviewed as suitable models to assess (anti)estrogenic and (anti)androgenic MOAs influencing reproductive biology as well as (anti)thyroidal MOAs interfering with the thyroid system. The development of targeted bioassays in combination with adequate chemical analyses is the prerequisite for a concise risk assessment of ED.

  12. Two novel antimicrobial peptides from skin venoms of spadefoot toad Megophrys minor.

    Science.gov (United States)

    Yang, Hong-Ling; Shen, Zhi-Qiang; Liu, Xuan; Kong, Yi

    2016-04-01

    Amphibian skin contains rich bioactive peptides. Especially, a large amount of antimicrobial peptides have been identified from amphibian skin secretions. Antimicrobial peptides display potent cytolytic activities against a range of pathogenic bacteria and fungi and play important defense roles. No antimicrobial peptides have been reported from toads belonging to the family of Pelobatidae. In this work, two novel antimicrobial peptides (Megin 1 and Megin 2) were purified and characterized from the skin venoms of spadefoot toad Megophrys minor (Pelobatidae, Anura, Amphibia). Megin 1 had an amino acid sequence of FLKGCWTKWYSLKPKCPF-NH2, which was composed of 18 amino acid residues and contained an intra-molecular disulfide bridge and an amidated C-terminus. Megin 2 had an amino acid sequence of FFVLKFLLKWAGKVGLEHLACKFKNWC, which was composed of 27 amino acid residues and contained an intra-molecular disulfide bridge. Both Megin 1 and Megin 2 showed potential antimicrobial abilities against bacteria and fungi. The MICs of Megin 1 against Escherichia coli, Bacillus dysenteriae, Staphylococcus aureus, Bacillus subtilis, and Candida albicans were 25, 3, 6.25, 3, and 50 μg·mL(-1), respectively. The corresponding MICs for Megin 2 were 6.25, 1.5, 12.5, 1.5, and 12.5 μg·mL(-1), respectively. They also exerted strong hemolytic activity against human and rabbit red cells. The results suggested that megin peptides in the toad skin of M. minor displayed toxic effects on both eukaryotes and prokaryotes. This was the first report of antimicrobial peptides from amphibians belonging to the family of Pelobatidae.

  13. Venom proteomic and venomous glands transcriptomic analysis of the Egyptian scorpion Scorpio maurus palmatus (Arachnida: Scorpionidae).

    Science.gov (United States)

    Abdel-Rahman, Mohamed A; Quintero-Hernandez, Veronica; Possani, Lourival D

    2013-11-01

    Proteomic analysis of the scorpion venom Scorpio maurus palmatus was performed using reverse-phase HPLC separation followed by mass spectrometry determination. Sixty five components were identified with molecular masses varying from 413 to 14,009 Da. The high percentage of peptides (41.5%) was from 3 to 5 KDa which may represent linear antimicrobial peptides and KScTxs. Also, 155 expressed sequence tags (ESTs) were analyzed through construction the cDNA library prepared from a pair of venomous gland. About 77% of the ESTs correspond to toxin-like peptides and proteins with definite open reading frames. The cDNA sequencing results also show the presence of sequences whose putative products have sequence similarity with antimicrobial peptides (24%), insecticidal toxins, β-NaScTxs, κ-KScTxs, α-KScTxs, calcines and La1-like peptides. Also, we have obtained 23 atypical types of venom molecules not recorded in other scorpion species. Moreover, 9% of the total ESTs revealed significant similarities with proteins involved in the cellular processes of these scorpion venomous glands. This is the first set of molecular masses and transcripts described from this species, in which various venom molecules have been identified. They belong to either known or unassigned types of scorpion venom peptides and proteins, and provide valuable information for evolutionary analysis and venomics.

  14. The state of amphibians in the United States

    Science.gov (United States)

    Muths, E.; Adams, M.J.; Grant, E.H.C.; Miller, D.; Corn, P.S.; Ball, L.C.

    2012-01-01

    More than 25 years ago, scientists began to identify unexplained declines in amphibian populations around the world. Much has been learned since then, but amphibian declines have not abated and the interactions among the various threats to amphibians are not clear. Amphibian decline is a problem of local, national, and international scope that can affect ecosystem function, biodiversity, and commerce. This fact sheet provides a snapshot of the state of the amphibians and introduces examples to illustrate the range of issues in the United States.

  15. Prevalence of the amphibian pathogen Batrachochytrium dendrobatidis in stream and wetland amphibians in Maryland, USA

    Science.gov (United States)

    Campbell Grant, Evan H.; Bailey, Larissa L.; Ware, Joy L.; Duncan, Karen L.

    2008-01-01

    The amphibian chytrid fungus Batrachochytrium dendrobatidis, responsible for the potentially fatal amphibian disease chytridiomycosis, is known to occur in a large and ever increasing number of amphibian populations around the world. However, sampling has been biased towards stream- and wetland-breeding anurans, with little attention paid to stream-associated salamanders. We sampled three frog and three salamander species in the Chesapeake and Ohio Canal National Historic Park, Maryland, by swabbing animals for PCR analysis to detect DNA of B. dendrobatidis. Using PCR, we detected B. dendrobatidis DNA in both stream and wetland amphibians, and report here the first occurrence of the pathogen in two species of stream-associated salamanders. Future research should focus on mechanisms within habitats that may affect persistence and dissemination of B. dendrobatidis among stream-associated salamanders

  16. Scorpion Venom and the Inflammatory Response

    Directory of Open Access Journals (Sweden)

    Vera L. Petricevich

    2010-01-01

    Full Text Available Scorpion venoms consist of a complex of several toxins that exhibit a wide range of biological properties and actions, as well as chemical compositions, toxicity, and pharmacokinetic and pharmacodynamic characteristics. These venoms are associated with high morbility and mortality, especially among children. Victims of envenoming by a scorpion suffer a variety of pathologies, involving mainly both sympathetic and parasympathetic stimulation as well as central manifestations such as irritability, hyperthermia, vomiting, profuse salivation, tremor, and convulsion. The clinical signs and symptoms observed in humans and experimental animals are related with an excessive systemic host inflammatory response to stings and stings, respectively. Although the pathophysiology of envenomation is complex and not yet fully understood, venom and immune responses are known to trigger the release of inflammatory mediators that are largely mediated by cytokines. In models of severe systemic inflammation produced by injection of high doses of venom or venoms products, the increase in production of proinflammatory cytokines significantly contributes to immunological imbalance, multiple organ dysfunction and death. The cytokines initiate a cascade of events that lead to illness behaviors such as fever, anorexia, and also physiological events in the host such as activation of vasodilatation, hypotension, and increased of vessel permeability.

  17. The role of amphibian antimicrobial peptides in protection of amphibians from pathogens linked to global amphibian declines.

    Science.gov (United States)

    Rollins-Smith, Louise A

    2009-08-01

    Amphibian species have experienced population declines and extinctions worldwide that are unprecedented in recent history. Many of these recent declines have been linked to a pathogenic skin fungus, Batrachochytrium dendrobatidis, or to iridoviruses of the genus Ranavirus. One of the first lines of defense against pathogens that enter by way of the skin are antimicrobial peptides synthesized and stored in dermal granular glands and secreted into the mucus following alarm or injury. Here, I review what is known about the capacity of amphibian antimicrobial peptides from diverse amphibians to inhibit B. dendrobatidis or ranavirus infections. When multiple species were compared for the effectiveness of their in vitro antimicrobial peptides defenses against B. dendrobatidis, non-declining species of rainforest amphibians had more effective antimicrobial peptides than species in the same habitat that had recently experienced population declines. Further, there was a significant correlation between the effectiveness of the antimicrobial peptides and resistance of the species to experimental infection. These studies support the hypothesis that antimicrobial peptides are an important component of innate defenses against B. dendrobatidis. Some amphibian antimicrobial peptides inhibit ranavirus infections and infection of human T lymphocytes by the human immunodeficiency virus (HIV). An effective antimicrobial peptide defense against skin pathogens appears to depend on a diverse array of genes expressing antimicrobial peptides. The production of antimicrobial peptides may be regulated by signals from the pathogens. However, this defense must also accommodate potentially beneficial microbes on the skin that compete or inhibit growth of the pathogens. How this delicate balancing act is accomplished is an important area of future research.

  18. Presence of the amphibian chytrid fungus Batrachochytrium dendrobatidis in native amphibians exported from Madagascar.

    Directory of Open Access Journals (Sweden)

    Jonathan E Kolby

    Full Text Available The emerging infectious disease chytridiomycosis is driven by the spread of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd, a highly virulent pathogen threatening global amphibian biodiversity. Although pandemic in distribution, previous intensive field surveys have failed to detect Bd in Madagascar, a biodiversity hotspot home to hundreds of endemic amphibian species. Due to the presence of Bd in nearby continental Africa and the ecological crisis that can be expected following establishment in Madagascar, enhanced surveillance is imperative. I sampled 565 amphibians commercially exported from Madagascar for the presence of Bd upon importation to the USA, both to assist early detection efforts and demonstrate the conservation potential of wildlife trade disease surveillance. Bd was detected in three animals via quantitative PCR: a single Heterixalus alboguttatus, Heterixalus betsileo, and Scaphiophryne spinosa. This is the first time Bd has been confirmed in amphibians from Madagascar and presents an urgent call to action. Our early identification of pathogen presence prior to widespread infection provides the necessary tools and encouragement to catalyze a swift, targeted response to isolate and eradicate Bd from Madagascar. If implemented before establishment occurs, an otherwise likely catastrophic decline in amphibian biodiversity may be prevented.

  19. Presence of the amphibian chytrid fungus Batrachochytrium dendrobatidis in native amphibians exported from Madagascar.

    Science.gov (United States)

    Kolby, Jonathan E

    2014-01-01

    The emerging infectious disease chytridiomycosis is driven by the spread of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd), a highly virulent pathogen threatening global amphibian biodiversity. Although pandemic in distribution, previous intensive field surveys have failed to detect Bd in Madagascar, a biodiversity hotspot home to hundreds of endemic amphibian species. Due to the presence of Bd in nearby continental Africa and the ecological crisis that can be expected following establishment in Madagascar, enhanced surveillance is imperative. I sampled 565 amphibians commercially exported from Madagascar for the presence of Bd upon importation to the USA, both to assist early detection efforts and demonstrate the conservation potential of wildlife trade disease surveillance. Bd was detected in three animals via quantitative PCR: a single Heterixalus alboguttatus, Heterixalus betsileo, and Scaphiophryne spinosa. This is the first time Bd has been confirmed in amphibians from Madagascar and presents an urgent call to action. Our early identification of pathogen presence prior to widespread infection provides the necessary tools and encouragement to catalyze a swift, targeted response to isolate and eradicate Bd from Madagascar. If implemented before establishment occurs, an otherwise likely catastrophic decline in amphibian biodiversity may be prevented.

  20. Full-Length Venom Protein cDNA Sequences from Venom-Derived mRNA: Exploring Compositional Variation and Adaptive Multigene Evolution.

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    Cassandra M Modahl

    2016-06-01

    Full Text Available Envenomation of humans by snakes is a complex and continuously evolving medical emergency, and treatment is made that much more difficult by the diverse biochemical composition of many venoms. Venomous snakes and their venoms also provide models for the study of molecular evolutionary processes leading to adaptation and genotype-phenotype relationships. To compare venom complexity and protein sequences, venom gland transcriptomes are assembled, which usually requires the sacrifice of snakes for tissue. However, toxin transcripts are also present in venoms, offering the possibility of obtaining cDNA sequences directly from venom. This study provides evidence that unknown full-length venom protein transcripts can be obtained from the venoms of multiple species from all major venomous snake families. These unknown venom protein cDNAs are obtained by the use of primers designed from conserved signal peptide sequences within each venom protein superfamily. This technique was used to assemble a partial venom gland transcriptome for the Middle American Rattlesnake (Crotalus simus tzabcan by amplifying sequences for phospholipases A2, serine proteases, C-lectins, and metalloproteinases from within venom. Phospholipase A2 sequences were also recovered from the venoms of several rattlesnakes and an elapid snake (Pseudechis porphyriacus, and three-finger toxin sequences were recovered from multiple rear-fanged snake species, demonstrating that the three major clades of advanced snakes (Elapidae, Viperidae, Colubridae have stable mRNA present in their venoms. These cDNA sequences from venom were then used to explore potential activities derived from protein sequence similarities and evolutionary histories within these large multigene superfamilies. Venom-derived sequences can also be used to aid in characterizing venoms that lack proteomic profiles and identify sequence characteristics indicating specific envenomation profiles. This approach, requiring only

  1. Variability of Venom-Neutralizing Properties of Serum from Snakes of the Colubrid Genus Lampropeltis

    Science.gov (United States)

    1992-01-01

    venoms of C. atrx , S. m. bar- potentials for C s. scauhatus (type B) venom bouri, or A. c. mokasen showed persistent (Table 2). inflammation and/or edema...tested, those injected with venom alone. This suggests Harvey (1960) described inhibition of C. atrx that elapid venom myolytic phospholipases Al venom

  2. The Comparison of Effectiveness between Bee Venom and Sweet Bee Venom Therapy on Low back pain with Radiating pain

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    Lee Tae-ho

    2007-12-01

    Full Text Available Objective : The aim of this study is to investigate if Sweet Bee Venom therapy has the equal effect in comparison with Bee Venom Therapy on Low back pain with Radiation pain. Methods : Clinical studies were done 24 patients who were treated low back pain with radiation pain to Dept. of Acupuncture & Moxibusition, of Oriental Medicine Se-Myung University from April 1, 2007 to September 30, 2007. Subjects were randomly divided into two groups ; Bee Venom treated group(Group A, n=10, Sweet Bee Venom treatred group(Group B, n=14. In Bee Venom treated group(Group A, we treated patients with dry needle acupuncture and Bee Venom therapy. In Sweet Bee Venom treatred group(Group B, we treated patients with dry needle acupuncture and Sweet Bee Venom therapy. All process of treatment were performed by double blinding method. To estimate the efficacy of controlling pain. we checked Visual Analog Scale(VAS. For evaluating functional change of patients, Straight Leg Raising Test(S.L.R.T was measured. Results :1. In controlling pain, Sweet Bee Venom treatred group(Group B had similar ability in comparison with Bee Venom treated group(Group A. 2. In promoting function, Sweet Bee Venom treatred group(Group B had similar ability in comparison with Bee Venom treated group(Group A. Conclusions : It may be equal effects as compared with using Bee Venom to treat low back pain with radiation pain using Sweet Bee Venom. We can try to treat other disease known to have effect with Bee Venom.

  3. Managing Amphibian Disease with Skin Microbiota.

    Science.gov (United States)

    Woodhams, Douglas C; Bletz, Molly; Kueneman, Jordan; McKenzie, Valerie

    2016-03-01

    The contribution of emerging amphibian diseases to the sixth mass extinction is driving innovative wildlife management strategies, including the use of probiotics. Bioaugmentation of the skin mucosome, a dynamic environment including host and microbial components, may not provide a generalized solution. Multi-omics technologies and ecological context underlie effective implementation.

  4. Culture of Cells from Amphibian Embryos.

    Science.gov (United States)

    Stanisstreet, Martin

    1983-01-01

    Describes a method for in vitro culturing of cells from amphibian early embryos. Such cells can be used to demonstrate such properties of eukaryote cells as cell motility, adhesion, differentiation, and cell sorting into tissues. The technique may be extended to investigate other factors. (Author/JN)

  5. Universal COI primers for DNA barcoding amphibians.

    Science.gov (United States)

    Che, Jing; Chen, Hong-Man; Yang, Jun-Xiao; Jin, Jie-Qiong; Jiang, Ke; Yuan, Zhi-Yong; Murphy, Robert W; Zhang, Ya-Ping

    2012-03-01

    DNA barcoding is a proven tool for the rapid and unambiguous identification of species, which is essential for many activities including the vouchering tissue samples in the genome 10K initiative, genealogical reconstructions, forensics and biodiversity surveys, among many other applications. A large-scale effort is underway to barcode all amphibian species using the universally sequenced DNA region, a partial fragment of mitochondrial cytochrome oxidase subunit I COI. This fragment is desirable because it appears to be superior to 16S for barcoding, at least for some groups of salamanders. The barcoding of amphibians is essential in part because many species are now endangered. Unfortunately, existing primers for COI often fail to achieve this goal. Herein, we report two new pairs of primers (➀, ➁) that in combination serve to universally amplify and sequence all three orders of Chinese amphibians as represented by 36 genera. This taxonomic diversity, which includes caecilians, salamanders and frogs, suggests that the new primer pairs will universally amplify COI for the vast majority species of amphibians.

  6. Centipede Venoms and Their Components: Resources for Potential Therapeutic Applications

    Directory of Open Access Journals (Sweden)

    Md Abdul Hakim

    2015-11-01

    Full Text Available Venomous animals have evolved with sophisticated bio-chemical strategies to arrest prey and defend themselves from natural predators. In recent years, peptide toxins from venomous animals have drawn considerable attention from researchers due to their surprising chemical, biochemical, and pharmacological diversity. Similar to other venomous animals, centipedes are one of the crucial venomous arthropods that have been used in traditional medicine for hundreds of years in China. Despite signifying pharmacological importance, very little is known about the active components of centipede venoms. More than 500 peptide sequences have been reported in centipede venomous glands by transcriptome analysis, but only a small number of peptide toxins from centipede has been functionally described. Like other venomous animals such as snakes, scorpions, and spiders, the venom of centipedes could be an excellent source of peptides for developing drugs for treatments as well as bio-insecticides for agrochemical applications. Although centipede venoms are yet to be adequately studied, the venom of centipedes as well as their components described to date, should be compiled to help further research. Therefore, based on previous reports, this review focusses on findings and possible therapeutic applications of centipede venoms as well as their components.

  7. Dynamic evolution of venom proteins in squamate reptiles.

    Science.gov (United States)

    Casewell, Nicholas R; Huttley, Gavin A; Wüster, Wolfgang

    2012-01-01

    Phylogenetic analyses of toxin gene families have revolutionised our understanding of the origin and evolution of reptile venoms, leading to the current hypothesis that venom evolved once in squamate reptiles. However, because of a lack of homologous squamate non-toxin sequences, these conclusions rely on the implicit assumption that recruitments of protein families into venom are both rare and irreversible. Here we use sequences of homologous non-toxin proteins from two snake species to test these assumptions. Phylogenetic and ancestral-state analyses revealed frequent nesting of 'physiological' proteins within venom toxin clades, suggesting early ancestral recruitment into venom followed by reverse recruitment of toxins back to physiological roles. These results provide evidence that protein recruitment into venoms from physiological functions is not a one-way process, but dynamic, with reversal of function and/or co-expression of toxins in different tissues. This requires a major reassessment of our previous understanding of how animal venoms evolve.

  8. Inflammatory effects of snake venom metalloproteinases

    Directory of Open Access Journals (Sweden)

    Catarina de Fátima Pereira Teixeira

    2005-03-01

    Full Text Available Metalloproteinases are abundant enzymes in crotaline and viperine snake venoms. They are relevant in the pathophysiology of envenomation, being responsible for local and systemic hemorrhage frequently observed in the victims. Snake venom metalloproteinases (SVMP are zinc-dependent enzymes of varying molecular weights having multidomain organization. Some SVMP comprise only the proteinase domain, whereas others also contain a disintegrin-like domain, cysteine-rich, and lectin domains. They have strong structural similarities with both mammalian matrix metalloproteinases (MMP and members of ADAMs (a disintegrin and metalloproteinase group. Besides hemorrhage, snake venom metalloproteinase induce local myonecrosis, skin damage, and inflammatory reaction in experimental models. Local inflammation is an important characteristic of snakebite envenomations inflicted by viperine and crotaline snake species. Thus, in the recent years there is a growing effort to understand the mechanisms responsible for SVMP-induced inflammatory reaction and the structural determinants of this effect. This short review focuses the inflammatory effects evoked by SVMP.

  9. Quantitative Proteomic Analysis of Venoms from Russian Vipers of Pelias Group: Phospholipases A2 are the Main Venom Components

    Directory of Open Access Journals (Sweden)

    Sergey I. Kovalchuk

    2016-04-01

    Full Text Available Venoms of most Russian viper species are poorly characterized. Here, by quantitative chromato-mass-spectrometry, we analyzed protein and peptide compositions of venoms from four Vipera species (V. kaznakovi, V. renardi, V. orlovi and V. nikolskii inhabiting different regions of Russia. In all these species, the main components were phospholipases A2, their content ranging from 24% in V. orlovi to 65% in V. nikolskii. Altogether, enzyme content in venom of V. nikolskii reached ~85%. Among the non-enzymatic proteins, the most abundant were disintegrins (14% in the V. renardi venom, C-type lectin like (12.5% in V. kaznakovi, cysteine-rich venom proteins (12% in V. orlovi and venom endothelial growth factors (8% in V. nikolskii. In total, 210 proteins and 512 endogenous peptides were identified in the four viper venoms. They represented 14 snake venom protein families, most of which were found in the venoms of Vipera snakes previously. However, phospholipase B and nucleotide degrading enzymes were reported here for the first time. Compositions of V. kaznakovi and V. orlovi venoms were described for the first time and showed the greatest similarity among the four venoms studied, which probably reflected close relationship between these species within the “kaznakovi” complex.

  10. Allergen immunotherapy for insect venom allergy

    DEFF Research Database (Denmark)

    Dhami, S; Zaman, H; Varga, Eva-Maria

    2017-01-01

    BACKGROUND: The European Academy of Allergy and Clinical Immunology (EAACI) is in the process of developing the EAACI Guidelines on Allergen Immunotherapy (AIT) for the management of insect venom allergy. To inform this process, we sought to assess the effectiveness, cost-effectiveness and safety...... of AIT in the management of insect venom allergy. METHODS: We undertook a systematic review, which involved searching 15 international biomedical databases for published and unpublished evidence. Studies were independently screened and critically appraised using established instruments. Data were...

  11. THE USE OF THE ANTI-VENOM SPECIFIC ANTIBODIES ISOLATED FROM DUCK EGGS FOR INACTIVATION OF THE VIPER VENOM

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    ADRIANA CRISTE

    2013-12-01

    Full Text Available The activity of specific anti-venom can be demonstrated using protection test in laboratory mice. Our study aimed to emphasize the possibility of viper venom inactivation by the antibodies produced and isolated from duck eggs and also to the activation concentration of these antibodies. The venom used for inoculation was harvested from two viper species (Vipera ammodytes and Vipera berus. The immunoglobulin extract had a better activity on the venom from Vipera berus compared to the venom from Vipera ammodytes. This could be the result of a better immunological response, as consequence of the immunization with this type of venom, compared to the response recorded when the Vipera ammodytes venom was used. Besides the advantages of low cost, high productivity and reduced risk of anaphylactic shock, the duck eggs also have high activity up to dilutions of 1/16, 1/32, respectively, with specific activity and 100 surviving in individuals which received 3 x DL50.

  12. Long-term primary culture of secretory cells of Bothrops jararaca venom gland for venom production in vitro.

    Science.gov (United States)

    Yamanouye, Norma; Kerchove, Celine Marie; Moura-da-Silva, Ana Maria; Carneiro, Sylvia M; Markus, Regina P

    2006-01-01

    This protocol details the optimal conditions to establish a long-term primary culture of secretory cells from the venom gland of the Bothrops jararaca snake. Furthermore, these conditions allow the production and secretion of venom into the culture medium. Snake venom is a rich source of active molecules and has been used for bioprospection studies. However, obtaining enough venom from snakes is a major obstacle. Secretory cells of venom glands are capable of producing active toxins. Therefore, a culture of secretory cells is a good in vitro system to acquire the venom of snakes without capturing the animal from the wild. The protocol described here provides a rapid (approximately 4 h) and reproducible means of producing sufficient amounts of snake venom for biological investigations.

  13. Amphibians as animal models for laboratory research in physiology.

    Science.gov (United States)

    Burggren, Warren W; Warburton, Stephen

    2007-01-01

    The concept of animal models is well honored, and amphibians have played a prominent part in the success of using key species to discover new information about all animals. As animal models, amphibians offer several advantages that include a well-understood basic physiology, a taxonomic diversity well suited to comparative studies, tolerance to temperature and oxygen variation, and a greater similarity to humans than many other currently popular animal models. Amphibians now account for approximately 1/4 to 1/3 of lower vertebrate and invertebrate research, and this proportion is especially true in physiological research, as evident from the high profile of amphibians as animal models in Nobel Prize research. Currently, amphibians play prominent roles in research in the physiology of musculoskeletal, cardiovascular, renal, respiratory, reproductive, and sensory systems. Amphibians are also used extensively in physiological studies aimed at generating new insights in evolutionary biology, especially in the investigation of the evolution of air breathing and terrestriality. Environmental physiology also utilizes amphibians, ranging from studies of cryoprotectants for tissue preservation to physiological reactions to hypergravity and space exploration. Amphibians are also playing a key role in studies of environmental endocrine disruptors that are having disproportionately large effects on amphibian populations and where specific species can serve as sentinel species for environmental pollution. Finally, amphibian genera such as Xenopus, a genus relatively well understood metabolically and physiologically, will continue to contribute increasingly in this new era of systems biology and "X-omics."

  14. Fossilized venom: the unusually conserved venom profiles of Heloderma species (beaded lizards and gila monsters).

    Science.gov (United States)

    Koludarov, Ivan; Jackson, Timothy N W; Sunagar, Kartik; Nouwens, Amanda; Hendrikx, Iwan; Fry, Bryan G

    2014-12-22

    Research into snake venoms has revealed extensive variation at all taxonomic levels. Lizard venoms, however, have received scant research attention in general, and no studies of intraclade variation in lizard venom composition have been attempted to date. Despite their iconic status and proven usefulness in drug design and discovery, highly venomous helodermatid lizards (gila monsters and beaded lizards) have remained neglected by toxinological research. Proteomic comparisons of venoms of three helodermatid lizards in this study has unravelled an unusual similarity in venom-composition, despite the long evolutionary time (~30 million years) separating H. suspectum from the other two species included in this study (H. exasperatum and H. horridum). Moreover, several genes encoding the major helodermatid toxins appeared to be extremely well-conserved under the influence of negative selection (but with these results regarded as preliminary due to the scarcity of available sequences). While the feeding ecologies of all species of helodermatid lizard are broadly similar, there are significant morphological differences between species, which impact upon relative niche occupation.

  15. Fossilized Venom: The Unusually Conserved Venom Profiles of Heloderma Species (Beaded Lizards and Gila Monsters

    Directory of Open Access Journals (Sweden)

    Ivan Koludarov

    2014-12-01

    Full Text Available Research into snake venoms has revealed extensive variation at all taxonomic levels. Lizard venoms, however, have received scant research attention in general, and no studies of intraclade variation in lizard venom composition have been attempted to date. Despite their iconic status and proven usefulness in drug design and discovery, highly venomous helodermatid lizards (gila monsters and beaded lizards have remained neglected by toxinological research. Proteomic comparisons of venoms of three helodermatid lizards in this study has unravelled an unusual similarity in venom-composition, despite the long evolutionary time (~30 million years separating H. suspectum from the other two species included in this study (H. exasperatum and H. horridum. Moreover, several genes encoding the major helodermatid toxins appeared to be extremely well-conserved under the influence of negative selection (but with these results regarded as preliminary due to the scarcity of available sequences. While the feeding ecologies of all species of helodermatid lizard are broadly similar, there are significant morphological differences between species, which impact upon relative niche occupation.

  16. Mediterranean Jellyfish Venoms: A Review on Scyphomedusae

    Directory of Open Access Journals (Sweden)

    Gian Luigi Mariottini

    2010-04-01

    Full Text Available The production of natural toxins is an interesting aspect, which characterizes the physiology and the ecology of a number of marine species that use them for defence/offence purposes. Cnidarians are of particular concern from this point of view; their venoms are contained in specialized structures–the nematocysts–which, after mechanical or chemical stimulation, inject the venom in the prey or in the attacker. Cnidarian stinging is a serious health problem for humans in the zones where extremely venomous jellyfish or anemones are common, such as in temperate and tropical oceanic waters and particularly along several Pacific coasts, and severe cases of envenomation, including also lethal cases mainly induced by cubomedusae, were reported. On the contrary, in the Mediterranean region the problem of jellyfish stings is quite modest, even though they can have anyhow an impact on public health and be of importance from the ecological and economic point of view owing to the implications on ecosystems and on some human activities such as tourism, bathing and fishing. This paper reviews the knowledge about the various aspects related to the occurrence and the stinging of the Mediterranean scyphozoan jellyfish as well as the activity of their venoms.

  17. Snake evolution and prospecting of snake venom

    NARCIS (Netherlands)

    Vonk, Freek Jacobus

    2012-01-01

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

  18. Venomous Animals; Are They Important in Iran?

    Directory of Open Access Journals (Sweden)

    Dehghani R.* PhD

    2015-12-01

    Full Text Available Many reports have indicated the medical importance of animal poisons in Iran. The significance numbers of Iranians are injured from high endemic to sporadic, by venomous snakes, scorpions, wasps, bees, fire and velvet ants, spiders and backswimmer bugs, so their nuisance prevention is an important task.

  19. Direct and indirect effects of climate change on amphibian populations

    Science.gov (United States)

    Blaustein, Andrew R.; Walls, Susan C.; Bancroft, Betsy A.; Lawler, Joshua J.; Searle, Catherine L.; Gervasi, Stephanie S.

    2010-01-01

    As part of an overall decline in biodiversity, populations of many organisms are declining and species are being lost at unprecedented rates around the world. This includes many populations and species of amphibians. Although numerous factors are affecting amphibian populations, we show potential direct and indirect effects of climate change on amphibians at the individual, population and community level. Shifts in amphibian ranges are predicted. Changes in climate may affect survival, growth, reproduction and dispersal capabilities. Moreover, climate change can alter amphibian habitats including vegetation, soil, and hydrology. Climate change can influence food availability, predator-prey relationships and competitive interactions which can alter community structure. Climate change can also alter pathogen-host dynamics and greatly influence how diseases are manifested. Changes in climate can interact with other stressors such as UV-B radiation and contaminants. The interactions among all these factors are complex and are probably driving some amphibian population declines and extinctions.

  20. Bee venom hypersensitivity and its management: patients perception of venom desensitisation.

    Science.gov (United States)

    Lui, C L; Heddle, R J; Kupa, A; Coates, T; Roberts-Thomson, P J

    1995-12-01

    The objectives of the study were to review bee venom immunotherapy from the patient's perspective: in particular its benefits and its problems, and to investigate any genetic tendency for bee venom hypersensitivity. A self administered, 9 item questionnaire was sent to 219 patients who had undergone either inpatient or outpatient bee venom immunotherapy at Flinders Medical Center. The clinic records of these patients were also reviewed. The controls for the genetic study were sought from patients, staff and students at Flinders University and Flinders Medical Centre. One hundred and forty-six questionnaires (some incomplete and anonymous) were received. The female to male ratio was 1:2.5. The age at the time of the initial anaphylactic reaction to a bee sting ranged between 2 to 59 years, with 67% of patients being less then 20 years old. Forty percent of patients underwent venom immunotherapy for a period less than 2 years with only 11% maintaining therapy for the recommended period of 5 years or more. Thirty three percent of patients stopped their therapy on their own accord. Bee stings occurring during bee venom immunotherapy (n = 56) were generally well tolerated except in 8 subjects, 7 of whom had not reached the maintenance dose. The reduction in systemic reactions to subsequent bee stings was significantly better in the study group receiving bee venom than in an historic control group treated with whole bee extract (p = 0.03). Fear of bee stings and restricted life styles were improved during or after venom immunotherapy. The frequency of a positive family history of systemic reactions to bee stings in the patient cohort was 31%, whereas in controls it was 15% (p = 0.013). Bee venom immunotherapy has dual benefits: patients are protected from subsequent sting anaphylaxis and there is reduced psychological morbidity. However, to be effective, venom immunotherapy requires a prolonged period of carefully supervised treatment and each venom injection can cause

  1. Global patterns of amphibian phylogenetic diversity

    DEFF Research Database (Denmark)

    Fritz, Susanne; Rahbek, Carsten

    2012-01-01

    phylogeny (2792 species). We combined each tree with global species distributions to map four indices of phylogenetic diversity. To investigate congruence between global spatial patterns of amphibian species richness and phylogenetic diversity, we selected Faith’s phylogenetic diversity (PD) index......Aim  Phylogenetic diversity can provide insight into how evolutionary processes may have shaped contemporary patterns of species richness. Here, we aim to test for the influence of phylogenetic history on global patterns of amphibian species richness, and to identify areas where macroevolutionary...... and the total taxonomic distinctness (TTD) index, because we found that the variance of the other two indices we examined (average taxonomic distinctness and mean root distance) strongly depended on species richness. We then identified regions with unusually high or low phylogenetic diversity given...

  2. Book review: Amphibians and reptiles in Minnesota

    Science.gov (United States)

    Mushet, David M.

    2014-01-01

    The photograph of a young boy poised to capture a wood frog (Lithobates sylvaticus) on page 3 of Amphibians and Reptiles in Minnesota captures perfectly the sense of awe and wonderment that one encounters throughout John Moriarty and Carol Hall’s new book. This is a spirit that most children possess naturally and that is so readily apparent when one of them comes face-to-face with one of the 53 species of frogs, toads, salamanders, turtles, lizards, or snakes that make Minnesota their home. This is a spirit that the authors have maintained in their hearts throughout almost 30 years of chasing, capturing, and studying amphibians and reptiles (a.k.a., herptiles or herps) in Minnesota. It is also the spirit that you will find reawakening in yourself as you turn from one page to the next and encounter the abundant color photos and descriptive text within this book.

  3. Neurosteroid biosynthesis in the brain of amphibians

    Directory of Open Access Journals (Sweden)

    Hubert eVaudry

    2011-11-01

    Full Text Available Amphibians have been widely used to investigate the synthesis of biologically active steroids in the brain and the regulation of neurosteroid production by neurotransmitters and neuropeptides. The aim of the present review is to summarize the current knowledge regarding the neuroanatomical distribution and biochemical activity of steroidogenic enzymes in the brain of anurans and urodeles. The data accumulated over the past two decades demonstrate that discrete populations of neurons and/or glial cells in the frog and newt brains express the major steroidogenic enzymes and are able to synthesize de novo a number of neurosteroids from cholesterol/pregnenolone. Since neurosteroidogenesis has been conserved during evolution from amphibians to mammals, it appears that neurosteroids must play important physiological functions in the central nervous system of vertebrates

  4. Pesticide Uptake Across the Amphibian Dermis Through Soil and Overspray Exposures

    Science.gov (United States)

    For terrestrial amphibians, accumulation ofpesticides through dermal contact is a primary route ofexposure in agricultural landscapes and may be contributingto widespread amphibian declines. To show pesticidetransfer across the amphibian dermis at permitted labelapplication rates...

  5. Pesticide Detection in Rainwater, Stemflow, and Amphibians from Agricultural Spray Drift in Southern Georgia, USA

    Science.gov (United States)

    Amphibians are important sentinel environmental species since they integrate stressors from both aquatic and terrestrial ecosystems. Pesticides are well established as a significant stressor for amphibians. In order to study spray-drift contributions to amphibian habitats, pestic...

  6. Neurosteroid Biosynthesis in the Brain of Amphibians

    OpenAIRE

    2011-01-01

    Amphibians have been widely used to investigate the synthesis of biologically active steroids in the brain and the regulation of neurosteroid production by neurotransmitters and neuropeptides. The aim of the present review is to summarize the current knowledge regarding the neuroanatomical distribution and biochemical activity of steroidogenic enzymes in the brain of anurans and urodeles. The data accumulated over the past two decades demonstrate that discrete populations of neurons and/or gl...

  7. Study on Bee venom and Pain

    Directory of Open Access Journals (Sweden)

    Hyoung-Seok Yun

    2000-07-01

    Full Text Available In order to study Bee venom and Pain, We searched Journals and Internet. The results were as follows: 1. The domestic papers were total 13. 4 papers were published at The journal of korean acupuncture & moxibustion society, 3 papers were published at The journal of korean oriental medical society, Each The journal of KyoungHee University Oriental Medicine and The journal of korean sports oriental medical society published 1 papers and Unpublished desertations were 3. The clinical studies were 4 and the experimental studies were 9. 2. The domestic clinical studies reported that Bee venom Herbal Acupuncture therapy was effective on HIVD, Subacute arthritis of Knee Joint and Sequale of sprain. In the domestic experimental studies, 5 were related to analgesic effect of Bee vnom and 4 were related to mechanism of analgesia. 3. The journals searched by PubMed were total 18. 5 papers were published at Pain, Each 2 papers were published at Neurosci Lett. and Br J Pharmacol, and Each Eur J Pain, J Rheumatol, Brain Res, Neuroscience, Nature and Toxicon et al published 1 paper. 4. In the journals searched by PubMed, Only the experimental studies were existed. 8 papers used Bee Venom as pain induction substance and 1 paper was related to analgesic effects of Bee venom. 5. 15 webpage were searched by internet related to Bee Venom and pain. 11 were the introduction related to arthritis, 1 was the advertisement, 1 was the patient's experience, 1 was the case report on RA, 1 was review article.

  8. Monitoring amphibians in Great Smoky Mountains National Park

    Science.gov (United States)

    Dodd, C. Kenneth

    2003-01-01

    Amphibian species have inexplicably declined or disappeared in many regions of the world, and in some instances, serious malformations have been observed. In the United States, amphibian declines frequently have occurred even in protected areas. Causes for the declines and malformations probably are varied and may not even be related. The seemingly sudden declines in widely separated areas, however, suggests a need to monitor amphibian populations as well as identify the causes when declines or malformations are discovered.

  9. Amphibians of the Ausoni Mountains (Latium, Central Italy)

    OpenAIRE

    Luigi Corsetti; Antonio Romano

    2007-01-01

    In this study we searched for amphibians in 89 potential breeding sites within the Ausoni Mounts, which are among the less investigated areas of Latium. Sixtynine spawning sites, and eight amphibian species (57.1% of the 14 amphibian species living in Latium region) were found. Reproductive activity was recorded for Salamandrina perspicillata, Triturus carnifex, Lissotriton vulgaris, Lissotriton italicus, Bufo bufo, Hyla intermedia, Rana italica and Pelophylax synklepton hispanica.

  10. Amphibians of the Ausoni Mountains (Latium, Central Italy

    Directory of Open Access Journals (Sweden)

    Luigi Corsetti

    2007-11-01

    Full Text Available In this study we searched for amphibians in 89 potential breeding sites within the Ausoni Mounts, which are among the less investigated areas of Latium. Sixtynine spawning sites, and eight amphibian species (57.1% of the 14 amphibian species living in Latium region were found. Reproductive activity was recorded for Salamandrina perspicillata, Triturus carnifex, Lissotriton vulgaris, Lissotriton italicus, Bufo bufo, Hyla intermedia, Rana italica and Pelophylax synklepton hispanica.

  11. Ranavirus outbreaks in amphibian populations of northern Idaho

    Science.gov (United States)

    Russell, Danelle M.; Goldberg, Caren S.; Sprague, Laura; Waits, Lisette P.; Green, D. Earl; Schuler, Krysten L.; Rosenblum, Erica Bree

    2011-01-01

    Ranavirus outbreaks, caused by pathogens in the genus Ranavirus (Family Iridoviridae), were the largest single cause of reported amphibian mass mortality events in the United States from 1996–2001 (Green et al. 2002). Mortality events associated with ranaviruses have been documented on five continents and throughout the latitudes and elevations where amphibians occur (Gray et al. 2009). However, the threat of ranaviruses to amphibian and reptile populations in specific regions is still largely unknown (Chinchar 2002; Gray et al. 2009).

  12. Status and trends of amphibian declines and extinctions worldwide.

    Science.gov (United States)

    Stuart, Simon N; Chanson, Janice S; Cox, Neil A; Young, Bruce E; Rodrigues, Ana S L; Fischman, Debra L; Waller, Robert W

    2004-12-01

    The first global assessment of amphibians provides new context for the well-publicized phenomenon of amphibian declines. Amphibians are more threatened and are declining more rapidly than either birds or mammals. Although many declines are due to habitat loss and overutilization, other, unidentified processes threaten 48% of rapidly declining species and are driving species most quickly to extinction. Declines are nonrandom in terms of species' ecological preferences, geographic ranges, and taxonomic associations and are most prevalent among Neotropical montane, stream-associated species. The lack of conservation remedies for these poorly understood declines means that hundreds of amphibian species now face extinction.

  13. Book review: The ecology and behavior of amphibians

    Science.gov (United States)

    Walls, Susan C.

    2008-01-01

    This state‐of‐the‐art book has made its timely emergence amid a crisis of global magnitude: that of population declines, range reductions, and extinctions of numerous species of amphibians. A clear understanding of the fundamental concepts in amphibian biology is crucial to the success of any conservation effort. This volume compiles the information necessary to acquire that basic understanding. It is a comprehensive synthesis of both traditional and contemporary facets of amphibian biology, spanning a breadth of topics ranging from phylogeny, physiology, behavior, population and community ecology, and conservation. As such, it undoubtedly takes its place among contemporary volumes as the single, authoritative source for basic topics relevant to amphibian life.

  14. Widespread Chemical Detoxification of Alkaloid Venom by Formicine Ants.

    Science.gov (United States)

    LeBrun, Edward G; Diebold, Peter J; Orr, Matthew R; Gilbert, Lawrence E

    2015-10-01

    The ability to detoxify defensive compounds of competitors provides key ecological advantages that can influence community-level processes. Although common in plants and bacteria, this type of detoxification interaction is extremely rare in animals. Here, using laboratory behavioral assays and analyses of videotaped interactions in South America, we report widespread venom detoxification among ants in the subfamily Formicinae. Across both data sets, nine formicine species, representing all major clades, used a stereotyped grooming behavior to self-apply formic acid (acidopore grooming) in response to fire ant (Solenopsis invicta and S. saevissima) venom exposure. In laboratory assays, this behavior increased the survivorship of species following exposure to S. invicta venom. Species expressed the behavior when exposed to additional alkaloid venoms, including both compositionally similar piperidine venom of an additional fire ant species and the pyrrolidine/pyrroline alkaloid venom of a Monomorium species. In addition, species expressed the behavior following exposure to the uncharacterized venom of a Crematogaster species. However, species did not express acidopore grooming when confronted with protein-based ant venoms or when exposed to monoterpenoid-based venom. This pattern, combined with the specific chemistry of the reaction of formic acid with venom alkaloids, indicates that alkaloid venoms are targets of detoxification grooming. Solenopsis thief ants, and Monomorium species stand out as brood-predators of formicine ants that produce piperidine, pyrrolidine, and pyrroline venom, providing an important ecological context for the use of detoxification behavior. Detoxification behavior also represents a mechanism that can influence the order of assemblage dominance hierarchies surrounding food competition. Thus, this behavior likely influences ant-assemblages through a variety of ecological pathways.

  15. Studies on Bee Venom and Its Medical Uses

    Science.gov (United States)

    Ali, Mahmoud Abdu Al-Samie Mohamed

    2012-07-01

    Use of honey and other bee products in human treatments traced back thousands of years and healing properties are included in many religious texts including the Veda, Bible and Quran. Apitherapy is the use of honey bee products for medical purposes, this include bee venom, raw honey, royal jelly, pollen, propolis, and beeswax. Whereas bee venom therapy is the use of live bee stings (or injectable venom) to treat various diseases such as arthritis, rheumatoid arthritis, multiple sclerosis (MS), lupus, sciatica, low back pain, and tennis elbow to name a few. It refers to any use of venom to assist the body in healing itself. Bee venom contains at least 18 pharmacologically active components including various enzymes, peptides and amines. Sulfur is believed to be the main element in inducing the release of cortisol from the adrenal glands and in protecting the body from infections. Contact with bee venom produces a complex cascade of reactions in the human body. The bee venom is safe for human treatments, the median lethal dose (LD50) for an adult human is 2.8 mg of venom per kg of body weight, i.e. a person weighing 60 kg has a 50% chance of surviving injections totaling 168 mg of bee venom. Assuming each bee injects all its venom and no stings are quickly removed at a maximum of 0.3 mg venom per sting, 560 stings could well be lethal for such a person. For a child weighing 10 kg, as little as 93.33 stings could be fatal. However, most human deaths result from one or few bee stings due to allergic reactions, heart failure or suffocation from swelling around the neck or the mouth. As compare with other human diseases, accidents and other unusual cases, the bee venom is very safe for human treatments.

  16. Modern trends in animal venom research - omics and nanomaterials

    Science.gov (United States)

    Utkin, Yuri N

    2017-01-01

    Animal venom research is a specialized investigation field, in which a number of different methods are used and this array is constantly expanding. Thus, recently emerged omics and nanotechnologies have already been successfully applied to venom research. Animal venoms have been studied for quite a long time. The traditional reductionist approach has been to isolate individual toxins and then study their structure and function. Unfortunately, the characterization of the venom as a whole system and its multiple effects on an entire organism were not possible until recent times. The development of new methods in mass spectrometry and sequencing have allowed such characterizations of venom, encompassing the identification of new toxins present in venoms at extremely low concentrations to changes in metabolism of prey organisms after envenomation. In particular, this type of comprehensive research has become possible due to the development of the various omics technologies: Proteomics, peptidomics, transcriptomics, genomics and metabolomics. As in other research fields, these omics technologies ushered in a revolution for venom studies, which is now entering the era of big data. Nanotechnology is a very new branch of technology and developing at an extremely rapid pace. It has found application in many spheres and has not bypassed the venom studies. Nanomaterials are quite promising in medicine, and most studies combining venoms and nanomaterials are dedicated to medical applications. Conjugates of nanoparticles with venom components have been proposed for use as drugs or diagnostics. For example, nanoparticles conjugated with chlorotoxin - a toxin in scorpion venom, which has been shown to bind specifically to glioma cells - are considered as potential glioma-targeted drugs, and conjugates of neurotoxins with fluorescent semiconductor nanoparticles or quantum dots may be used to detect endogenous targets expressed in live cells. The data on application of omics and

  17. Animal venom studies: Current benefits and future developments

    Institute of Scientific and Technical Information of China (English)

    Yuri; N; Utkin

    2015-01-01

    Poisonous organisms are represented in many taxa, including kingdom Animalia. During evolution, animals have developed special organs for production and injection of venoms. Animal venoms are complex mixtures, compositions of which depend on species producing venom. The most known and studied poisonous terrestrial animals are snakes, scorpions and spiders. Among marine animals, these are jellyfishes, anemones and cone snails. The toxic substances in the venom ofthese animals are mainly of protein and peptide origin. Recent studies have indicated that the single venom may contain up to several hundred different components producing diverse physiological effects. Bites or stings by certain poisonous species result in severe envenomations leading in some cases to death. This raises the problem of bite treatment. The most effective treatment so far is the application of antivenoms. To enhance the effectiveness of such treatments, the knowledge of venom composition is needed. On the other hand, venoms contain substances with unique biological properties, which can be used both in basic science and in clinical applications. The best example of toxin application in basic science is α-bungarotoxin the discovery of which made a big impact on the studies of nicotinic acetylcholine receptor. Today compositions of venom from many species have already been examined. Based on these data, one can conclude that venoms contain a large number of individual components belonging to a limited number of structural types. Often minor changes in the amino acid sequence give rise to new biological properties. Change in the living conditions of poisonous animals lead to alterations in the composition of venoms resulting in appearance of new toxins. At the same time introduction of new methods of proteomics and genomics lead to discoveries of new compounds, which may serve as research tools or as templates for the development of novel drugs. The application of these sensitive and

  18. [Use of medicinal plants against scorpionic and ophidian venoms].

    Science.gov (United States)

    Memmi, A; Sansa, G; Rjeibi, I; El Ayeb, M; Srairi-Abid, N; Bellasfer, Z; Fekhih, A

    2007-01-01

    The scorpionic and ophidian envenomations are a serious public health problem in Tunisia especially in Southeastern regions. In these regions Artemisia campestris L is a plant well known which has a very important place in traditional medicine for its effectiveness against alleged venom of scorpions and snakes. In this work, we tested for the first time, the anti-venomous activity of Artemisia campestris L against the scorpion Androctonus australis garzonii and the viper Macrovipera lebetina venoms. Assays were conducted by fixing the dose of extract to3 mg/mouse while doses of venom are variable. The leaves of Artemisia campestris L were extracted by various organic solvents (Ether of oil, ethyl acetate, methanol and ethanol) and each extract was tested for its venom neutralizing capacity. For the ethanolic extract, a significant activity with respect to the venoms of scorpion Androctonus australis garzonii (Aag), was detected. Similarly, a significant neutralizing activity against the venom of a viper Macrovipera lebetina (Ml), was obtained with the dichloromethane extract. These results suggest the presence of two different type of chemical components in this plant: those neutralizing the venom of scorpion are soluble in ethanol whereas those neutralizing the venom of viper are soluble in dichloromethane.

  19. Oral Absorption of Mesobuthus eupeus Scorpion Venom in Mice

    Directory of Open Access Journals (Sweden)

    Zohreh Hosseini

    2017-02-01

    Full Text Available Background: To explore the oral absorption of scorpion venom an ELISA were designed in this study. Scorpions and their venom were been used for centuries as medical treatments in traditional medicine. The oral administration of drug referred as the convenient way, as there was not any publication about gastro-intestinal absorption of scorpion venom; this experiment checked oral absorption of Mesobuthus eupeus scorpion venom in mice. Methods: Six groups of mice orally received 0, 0.2, 0.5, 1, 2 and 5 mg/kg of M. eupeus venom and their blood samples were tacked after 15, 30, 60 min and 2, 4, 6, 24, 48 h after that. The presence of venom the blood samples were detected with a house- antigen capture ELISA. Results: The venom was absorbed after its feeding to mice. The animals expressed no signs of envenomation and, the venom was detectable by AC-ELISA as soon as 15 min after its feed. Maximum serum levels were 2 h after its meal. Conclusion: The orally administrated venom was absorbed to the blood circulation without any clinically symptoms.

  20. A simple protocol for venom peptide barcoding in scorpions

    Directory of Open Access Journals (Sweden)

    Stephan Schaffrath

    2014-06-01

    Full Text Available Scorpion venoms contain many species-specific peptides which target ion channels in cell membranes. Without harming the scorpions, these peptides can easily be extracted and detected by MALDI-TOF mass spectrometry. So far, only few studies compared the venom of different species solely for taxonomic purposes. Here, we describe a very simple protocol for venom extraction and mass fingerprinting that was developed for peptide barcoding (venom code for species identification and facilitates reproducibility if sample preparation is performed under field conditions. This approach may serve as suitable basis for a taxonomy-oriented scorpion toxin database that interacts with MALDI-TOF mass spectra.

  1. Inhibitors of snake venoms and development of new therapeutics.

    Science.gov (United States)

    Sánchez, Elda E; Rodríguez-Acosta, Alexis

    2008-01-01

    Natural inhibitors of snake venoms play a significant role in the ability to neutralize the degradation effects induced by venom toxins. It has been known for many years that animal sera and some plant extracts are competent in neutralizing snake venoms. The purpose of this review is to highlight the recent work that has been accomplished with natural inhibitors of snake venoms as well as revisiting the past research including those found in plants. The biomedical value of these natural inhibitors can lead to the development of new therapeutics for an assortment of diseases as well as contributing to efficient antivenoms for the treatment of ophidic accidents.

  2. Effects of gamma radiation on bee venom: preliminary studies

    Energy Technology Data Exchange (ETDEWEB)

    Costa, H.; Boni-Mitake, M.; Souza, C.F.; Rogero, J.R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Div. de Radiobiologia

    1999-11-01

    Africanized honeybees are very common insects in Brazil and frequently cause accidents followed by important immunological reactions and even deaths. Their venoms are composed of a complex mixture of substances of general biological actions. several works utilizing ionizing radiation showed that it is able to modify protein structures, and successfully detoxify snake venoms toxins, although maintaining its immunological properties. The main objective of this paper was to study the effects of gamma radiation on bee venom, regarding some biochemical and toxicological aspects. Africanized Apis melllifera whole venom (2 mg/ml) in 0.15 M Na Cl solution was irradiated with 2 kGy in a {sup 60} Co source. Preliminary studies has been carried out in order to identify some biochemical changes after irradiation. Concerning this, irradiated and native venom were submitted to a molecular exclusion chromatography (Sephadex G-100), UV absorption spectrum and protein concentration analysis. It could be seen that irradiated bee venom spectrum presented differences when compared to native bee venom, suggesting that some structural alterations has occurred. Protein concentration and chromatography profiles were not changes after irradiation. In order to evaluate the toxicity a lethality assay (L D{sub 50}) has been performed with both venoms, and irradiated venom showed to be less toxic than native one. (author) 23 refs., 3 figs., 1 tab.

  3. Observations on white and yellow venoms from an individual southern Pacific rattlesnake (Crotalus viridis helleri).

    Science.gov (United States)

    Johnson, E K; Kardong, K V; Ownby, C L

    1987-01-01

    Biochemical differences in white and yellow venoms produced in the separate venom glands of an individual southern Pacific rattlesnake (Crotalus viridis helleri) were investigated. Compared to the yellow venom, the white venom contained fewer low molecular weight components and was considerably less toxic. Although the exact LD50 was not determined, the white venom did not produce toxic effects in mice when injected i.v. at concentrations up to 10 mg/kg. The i.v. LD50 of the yellow venom was approximately 1.6 mg/kg. Both white and yellow venoms had hemorrhagic activity, but the white venom caused less intradermal hemorrhage in mice. No L-amino acid oxidase activity was measured in the white venom and protease and phospholipase A2 activities of the white venom were much less than in the yellow venom. The white and yellow venoms both produced myonecrosis at 1, 3 and 24 hr after i.m. injection into mice, however, there were some qualitative differences in the myonecrosis produced. When the venom samples were reacted against Wyeth's polyvalent (Crotalidae) antivenom using immunodiffusion, three precipitin bands formed against the yellow venom, whereas only one formed against the white venom. When reacted against an antiserum to myotoxin alpha from C. viridis viridis venom, both the white and yellow venoms produced one precipitin band each.

  4. Conceptual Design for the Amphibian Research and Monitoring Initiative (ARMI)

    Science.gov (United States)

    Battaglin, W. A.; Langtimm, C. A.; Adams, M. J.; Gallant, A. L.; James, D. L.

    2001-12-01

    In 2000, the President of the United States (US) and Congress directed Department of Interior (DOI) agencies to develop a program for monitoring trends in amphibian populations on DOI lands and to conduct research into causes of declines. The U.S. Geological Survey (USGS) was given lead responsibility for planning and implementing the Amphibian Research and Monitoring Initiative (ARMI) in cooperation with the National Park Service (NPS), Fish and Wildlife Service, and Bureau of Land Management. The program objectives are to (1) establish a network for monitoring the status and distribution of amphibian species on DOI lands; (2) identify and monitor environmental conditions known to affect amphibian populations; (3) conduct research on causes of amphibian population change and malformations; and (4) provide information to resource managers, policy makers, and the public in support of amphibian conservation. The ARMI program will integrate research efforts of USGS, other Federal, and non-federal herpetologists, hydrologists, and geographers across the Nation. ARMI will conduct a small number (~20) of intensive research efforts (for example, studies linking amphibian population changes to hydrologic conditions) and a larger number (~50) of more generalized inventory and monitoring studies encompassing broader areas such as NPS units. ARMI will coordinate with and try to augment other amphibian inventory studies such as the National Amphibian Atlas and the North American Amphibian Monitoring Program. ARMI will develop and test protocols for the standardized collection of amphibian data and provide a centrally managed database designed to simplify data entry, retrieval, and analysis. ARMI pilot projects are underway at locations across the US.

  5. Global rates of habitat loss and implications for amphibian conservation

    Science.gov (United States)

    Gallant, A.L.; Klaver, R.W.; Casper, G.S.; Lannoo, M.J.

    2007-01-01

    A large number of factors are known to affect amphibian population viability, but most authors agree that the principal causes of amphibian declines are habitat loss, alteration, and fragmentation. We provide a global assessment of land use dynamics in the context of amphibian distributions. We accomplished this by compiling global maps of amphibian species richness and recent rates of change in land cover, land use, and human population growth. The amphibian map was developed using a combination of published literature and digital databases. We used an ecoregion framework to help interpret species distributions across environmental, rather than political, boundaries. We mapped rates of land cover and use change with statistics from the World Resources Institute, refined with a global digital dataset on land cover derived from satellite data. Temporal maps of human population were developed from the World Resources Institute database and other published sources. Our resultant map of amphibian species richness illustrates that amphibians are distributed in an uneven pattern around the globe, preferring terrestrial and freshwater habitats in ecoregions that are warm and moist. Spatiotemporal patterns of human population show that, prior to the 20th century, population growth and spread was slower, most extensive in the temperate ecoregions, and largely exclusive of major regions of high amphibian richness. Since the beginning of the 20th century, human population growth has been exponential and has occurred largely in the subtropical and tropical ecoregions favored by amphibians. Population growth has been accompanied by broad-scale changes in land cover and land use, typically in support of agriculture. We merged information on land cover, land use, and human population growth to generate a composite map showing the rates at which humans have been changing the world. When compared with the map of amphibian species richness, we found that many of the regions of the

  6. Effects of gamma radiation on snake venoms

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, N.; Spencer, P.J.; Andrade, H.F.; Guarnieri, M.C.; Rogero, J.R

    1998-06-01

    Ionizing radiation is able to detoxify several venoms, including snake venoms, without affecting significantly their immunogenic properties. In order to elucidate this phenomena, we conceived a comparative pharmacological study between native and irradiated (2,000 Gy) crotoxin, the main toxin of the South American rattlesnake Crotalus durissus terrificus. Crotoxin was isolated and purified by molecular exclusion chromatography, pI precipitation and, subsequently submitted to irradiation. Gel filtration of the irradiated toxin resulted in some high molecular weight aggregates formation. Crotoxin toxicity decreased two folds after irradiation, as determined by LD{sub 50} in mice. Native and irradiated crotoxin biodistribution ocurred in the same general manner, with renal elimination. However, in contrast to irradiated crotoxin, the native form was initially retained in kidneys. A later concentration (2-3 hr) appeared in phagocytic mononuclear cells rich organs (liver and spleen) and neural junction rich organs (muscle and brain)

  7. AMPHIBIAN DECLINES AND ENVIRONMENTAL CHANGE IN THE EASTERN "MOJAVE DESERT"

    Science.gov (United States)

    A number of amphibian species historically inhabited sparsely distributed wetlands in the Mojave Desert, USA, habitats that have been dramatically altered or eliminated as a result of human activities. The population status and distribution of amphibians were investigated in a 20...

  8. Amphibians and Reptiles from Paramakatoi and Kato, Guyana

    Science.gov (United States)

    MacCulloch, Ross D.; Reynolds, Robert P.

    2012-01-01

    We report the herpetofauna of two neighboring upland locations in west-central Guyana. Twenty amphibian and 24 reptile species were collected. Only 40% of amphibians and 12.5% of reptiles were collected in both locations. This is one of the few collections made at upland (750–800 m) locations in the Guiana Shield.

  9. All about Amphibians. Animal Life for Children. [Videotape].

    Science.gov (United States)

    2000

    This videotape teaches children about their favorite amphibious creatures, as well as amphibians' nearest cousins--toads, newts, and salamanders. Young students discover how these amazing creatures can live both in and out of water, learn about the amphibious life cycle, and compare the differences between amphibians and reptiles. This videotape…

  10. Climate change and amphibian diversity patterns in Mexico

    DEFF Research Database (Denmark)

    Ochoa-Ochoa, Leticia M.; Rodríguez, Pilar; Mora, Franz

    2012-01-01

    The aim of this article is to characterize at fine scale alpha and beta diversity patterns for Mexican amphibians and analyze how these patterns might change under a moderate climate-change scenario, highlighting the overall consequences for amphibian diversity at the country level. We used a geo...

  11. Peptidomic and transcriptomic profiling of four distinct spider venoms.

    Science.gov (United States)

    Oldrati, Vera; Koua, Dominique; Allard, Pierre-Marie; Hulo, Nicolas; Arrell, Miriam; Nentwig, Wolfgang; Lisacek, Frédérique; Wolfender, Jean-Luc; Kuhn-Nentwig, Lucia; Stöcklin, Reto

    2017-01-01

    Venom based research is exploited to find novel candidates for the development of innovative pharmacological tools, drug candidates and new ingredients for cosmetic and agrochemical industries. Moreover, venomics, as a well-established approach in systems biology, helps to elucidate the genetic mechanisms of the production of such a great molecular biodiversity. Today the advances made in the proteomics, transcriptomics and bioinformatics fields, favor venomics, allowing the in depth study of complex matrices and the elucidation even of minor compounds present in minute biological samples. The present study illustrates a rapid and efficient method developed for the elucidation of venom composition based on NextGen mRNA sequencing of venom glands and LC-MS/MS venom proteome profiling. The analysis of the comprehensive data obtained was focused on cysteine rich peptide toxins from four spider species originating from phylogenetically distant families for comparison purposes. The studied species were Heteropoda davidbowie (Sparassidae), Poecilotheria formosa (Theraphosidae), Viridasius fasciatus (Viridasiidae) and Latrodectus mactans (Theridiidae). This led to a high resolution profiling of 284 characterized cysteine rich peptides, 111 of which belong to the Inhibitor Cysteine Knot (ICK) structural motif. The analysis of H. davidbowie venom revealed a high richness in term of venom diversity: 95 peptide sequences were identified; out of these, 32 peptides presented the ICK structural motif and could be classified in six distinct families. The profiling of P. formosa venom highlighted the presence of 126 peptide sequences, with 52 ICK toxins belonging to three structural distinct families. V. fasciatus venom was shown to contain 49 peptide sequences, out of which 22 presented the ICK structural motif and were attributed to five families. The venom of L. mactans, until now studied for its large neurotoxins (Latrotoxins), revealed the presence of 14 cysteine rich

  12. Whole Transcriptome of the Venom Gland from Urodacus yaschenkoi Scorpion.

    Science.gov (United States)

    Luna-Ramírez, Karen; Quintero-Hernández, Verónica; Juárez-González, Víctor Rivelino; Possani, Lourival D

    2015-01-01

    Australian scorpion venoms have been poorly studied, probably because they do not pose an evident threat to humans. In addition, the continent has other medically important venomous animals capable of causing serious health problems. Urodacus yaschenkoi belongs to the most widely distributed family of Australian scorpions (Urodacidae) and it is found all over the continent, making it a useful model system for studying venom composition and evolution. This communication reports the whole set of mRNA transcripts produced by the venom gland. U. yaschenkoi venom is as complex as its overseas counterparts. These transcripts certainly code for several components similar to known scorpion venom components, such as: alpha-KTxs, beta-KTxs, calcins, protease inhibitors, antimicrobial peptides, sodium-channel toxins, toxin-like peptides, allergens, La1-like, hyaluronidases, ribosomal proteins, proteasome components and proteins related to cellular processes. A comparison with the venom gland transcriptome of Centruroides noxius (Buthidae) showed that these two scorpions have similar components related to biological processes, although important differences occur among the venom toxins. In contrast, a comparison with sequences reported for Urodacus manicatus revealed that these two Urodacidae species possess the same subfamily of scorpion toxins. A comparison with sequences of an U. yaschenkoi cDNA library previously reported by our group showed that both techniques are reliable for the description of the venom components, but the whole transcriptome generated with Next Generation Sequencing platform provides sequences of all transcripts expressed. Several of which were identified in the proteome, but many more transcripts were identified including uncommon transcripts. The information reported here constitutes a reference for non-Buthidae scorpion venoms, providing a comprehensive view of genes that are involved in venom production. Further, this work identifies new putative

  13. Estrogens can disrupt amphibian mating behavior.

    Directory of Open Access Journals (Sweden)

    Frauke Hoffmann

    Full Text Available The main component of classical contraceptives, 17α-ethinylestradiol (EE2, has high estrogenic activity even at environmentally relevant concentrations. Although estrogenic endocrine disrupting compounds are assumed to contribute to the worldwide decline of amphibian populations by adverse effects on sexual differentiation, evidence for EE2 affecting amphibian mating behaviour is lacking. In this study, we demonstrate that EE2 exposure at five different concentrations (0.296 ng/L, 2.96 ng/L, 29.64 ng/L, 2.96 µg/L and 296.4 µg/L can disrupt the mating behavior of adult male Xenopus laevis. EE2 exposure at all concentrations lowered male sexual arousal, indicated by decreased proportions of advertisement calls and increased proportions of the call type rasping, which characterizes a sexually unaroused state of a male. Additionally, EE2 at all tested concentrations affected temporal and spectral parameters of the advertisement calls, respectively. The classical and highly sensitive biomarker vitellogenin, on the other hand, was only induced at concentrations equal or higher than 2.96 µg/L. If kept under control conditions after a 96 h EE2 exposure (2.96 µg/L, alterations of male advertisement calls vanish gradually within 6 weeks and result in a lower sexual attractiveness of EE2 exposed males toward females as demonstrated by female choice experiments. These findings indicate that exposure to environmentally relevant EE2 concentrations can directly disrupt male mate calling behavior of X. laevis and can indirectly affect the mating behavior of females. The results suggest the possibility that EE2 exposure could reduce the reproductive success of EE2 exposed animals and these effects might contribute to the global problem of amphibian decline.

  14. Partners in amphibian and reptile conservation 2013 annual report

    Science.gov (United States)

    Conrad, Paulette M.; Weir, Linda A.; Nanjappa, Priya

    2014-01-01

    Partners in Amphibian and Reptile Conservation (PARC) was established in 1999 to address the widespread declines, extinctions, and range reductions of amphibians and reptiles, with a focus on conservation of taxa and habitats in North America. Amphibians and reptiles are affected by a broad range of human activities, both as incidental effects of habitat alteration and direct effect from overexploitation; these animals are also challenged by the perception that amphibians and reptiles are either dangerous or of little environmental or economic value. However, PARC members understand these taxa are important parts of our natural an cultural heritage and they serve important roles in ecosystems throughout the world. With many amphibians and reptiles classified as threatened with extinction, conservation of these animals has never been more important.

  15. Late Cretaceous vicariance in Gondwanan amphibians.

    Directory of Open Access Journals (Sweden)

    Ines Van Bocxlaer

    Full Text Available Overseas dispersals are often invoked when Southern Hemisphere terrestrial and freshwater organism phylogenies do not fit the sequence or timing of Gondwana fragmentation. We used dispersal-vicariance analyses and molecular timetrees to show that two species-rich frog groups, Microhylidae and Natatanura, display congruent patterns of spatial and temporal diversification among Gondwanan plates in the Late Cretaceous, long after the presumed major tectonic break-up events. Because amphibians are notoriously salt-intolerant, these analogies are best explained by simultaneous vicariance, rather than by oceanic dispersal. Hence our results imply Late Cretaceous connections between most adjacent Gondwanan landmasses, an essential concept for biogeographic and palaeomap reconstructions.

  16. Captive breeding, reintroduction, and the conservation of amphibians.

    Science.gov (United States)

    Griffiths, Richard A; Pavajeau, Lissette

    2008-08-01

    The global amphibian crisis has resulted in renewed interest in captive breeding as a conservation tool for amphibians. Although captive breeding and reintroduction are controversial management actions, amphibians possess a number of attributes that make them potentially good models for such programs. We reviewed the extent and effectiveness of captive breeding and reintroduction programs for amphibians through an analysis of data from the Global Amphibian Assessment and other sources. Most captive breeding and reintroduction programs for amphibians have focused on threatened species from industrialized countries with relatively low amphibian diversity. Out of 110 species in such programs, 52 were in programs with no plans for reintroduction that had conservation research or conservation education as their main purpose. A further 39 species were in programs that entailed captive breeding and reintroduction or combined captive breeding with relocations of wild animals. Nineteen species were in programs with relocations of wild animals only. Eighteen out of 58 reintroduced species have subsequently bred successfully in the wild, and 13 of these species have established self-sustaining populations. As with threatened amphibians generally, amphibians in captive breeding or reintroduction programs face multiple threats, with habitat loss being the most important. Nevertheless, only 18 out of 58 reintroduced species faced threats that are all potentially reversible. When selecting species for captive programs, dilemmas may emerge between choosing species that have a good chance of surviving after reintroduction because their threats are reversible and those that are doomed to extinction in the wild as a result of irreversible threats. Captive breeding and reintroduction programs for amphibians require long-term commitments to ensure success, and different management strategies may be needed for species earmarked for reintroduction and species used for conservation

  17. Grass Valley Venom FlashPak录像机

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Thomson新推出的Grass Valley Venom FIashPak录像机,可配合草谷VIPER Film Stream数字电影摄像机使用。Venom FlashPak是一款灵巧可靠的台式系统,可以记录VIPER摄影机输出的未压缩视频。

  18. Embriotoxic effects of maternal exposure to Tityus serrulatus scorpion venom

    Directory of Open Access Journals (Sweden)

    A. A. S. Barão

    2008-01-01

    Full Text Available Tityus serrulatus is the most venomous scorpion in Brazil; however, it is not known whether its venom causes any harm to the offspring whose mothers have received it. This study investigates whether the venom of T. serrulatus may lead to deleterious effects in the offspring, when once administered to pregnant rats at a dose that causes moderate envenomation (3mg/kg. The venom effects were studied on the 5th and on the 10th gestation day (GD5 and GD10. The maternal reproductive parameters of the group that received the venom on GD5 showed no alteration. The group that received the venom on GD10 presented an increase in post-implantation losses. In this group, an increase in the liver weight was also observed and one-third of the fetuses presented incomplete ossification of skull bones. None of the groups that received the venom had any visceral malformation or delay in the fetal development of their offspring. The histopathological analysis revealed not only placentas and lungs but also hearts, livers and kidneys in perfect state. Even having caused little effect on the dams, the venom may act in a more incisive way on the offspring, whether by stress generation or by a direct action.

  19. Recent Advances in Research on Widow Spider Venoms and Toxins

    Directory of Open Access Journals (Sweden)

    Shuai Yan

    2015-11-01

    Full Text Available Widow spiders have received much attention due to the frequently reported human and animal injures caused by them. Elucidation of the molecular composition and action mechanism of the venoms and toxins has vast implications in the treatment of latrodectism and in the neurobiology and pharmaceutical research. In recent years, the studies of the widow spider venoms and the venom toxins, particularly the α-latrotoxin, have achieved many new advances; however, the mechanism of action of the venom toxins has not been completely clear. The widow spider is different from many other venomous animals in that it has toxic components not only in the venom glands but also in other parts of the adult spider body, newborn spiderlings, and even the eggs. More recently, the molecular basis for the toxicity outside the venom glands has been systematically investigated, with four proteinaceous toxic components being purified and preliminarily characterized, which has expanded our understanding of the widow spider toxins. This review presents a glance at the recent advances in the study on the venoms and toxins from the Latrodectus species.

  20. Recent Advances in Research on Widow Spider Venoms and Toxins.

    Science.gov (United States)

    Yan, Shuai; Wang, Xianchun

    2015-11-27

    Widow spiders have received much attention due to the frequently reported human and animal injures caused by them. Elucidation of the molecular composition and action mechanism of the venoms and toxins has vast implications in the treatment of latrodectism and in the neurobiology and pharmaceutical research. In recent years, the studies of the widow spider venoms and the venom toxins, particularly the α-latrotoxin, have achieved many new advances; however, the mechanism of action of the venom toxins has not been completely clear. The widow spider is different from many other venomous animals in that it has toxic components not only in the venom glands but also in other parts of the adult spider body, newborn spiderlings, and even the eggs. More recently, the molecular basis for the toxicity outside the venom glands has been systematically investigated, with four proteinaceous toxic components being purified and preliminarily characterized, which has expanded our understanding of the widow spider toxins. This review presents a glance at the recent advances in the study on the venoms and toxins from the Latrodectus species.

  1. Accelerated evolution of crotalinae snake venom gland serine proteases.

    Science.gov (United States)

    Deshimaru, M; Ogawa, T; Nakashima, K; Nobuhisa, I; Chijiwa, T; Shimohigashi, Y; Fukumaki, Y; Niwa, M; Yamashina, I; Hattori, S; Ohno, M

    1996-11-11

    Eight cDNAs encoding serine proteases isolated from Trimeresurus flavoviridis (habu snake) and T. gramineus (green habu snake) venom gland cDNA libraries showed that nonsynonymous nucleotide substitutions have accumulated in the mature protein-coding regions to cause amino acid changes. Southern blot analysis of T. flavoviridis genomic DNAs using two proper probes indicated that venom gland serine protease genes form a multigene family in the genome. These observations suggest that venom gland serine proteases have diversified their amino acid sequences in an accelerating manner. Since a similar feature has been previously discovered in crotalinae snake venom gland phospholipase A2 (PLA2) isozyme genes, accelerated evolution appears to be universal in plural isozyme families of crotalinae snake venom gland.

  2. [Accidents with venomous and poisonous animals in Central Europe].

    Science.gov (United States)

    Bodio, Mauro; Junghanss, Thomas

    2009-05-01

    Central Europe is largely safe from accidents with venomous and poisonous animals. The regions where European vipers are regularly found are shrinking. Today accidents with jellyfish and stings of venomous fish afflicted during leisure activities at the sea side play the dominant role. Life threatening accidents in Europe are mainly due to exotic snakes held in captivity. A system useful in daily medical practice is explained to classify and stage accidents due to poisonous and venomous animals. The important poisonous and venomous animals of Central Europe and the specific therapeutics, the antivenoms, are covered. The antivenom depot "Antivenin-CH" of the Swiss Toxicology Information Centre in Zurich and the MRITox in Munich with the antivenom registry Munich AntiVenom INdex (MAVIN) are presented.

  3. Fetal adaptations for viviparity in amphibians.

    Science.gov (United States)

    Wake, Marvalee H

    2015-08-01

    Live-bearing has evolved in all three orders of amphibians--frogs, salamanders, and caecilians. Developing young may be either yolk dependent, or maternal nutrients may be supplied after yolk is resorbed, depending on the species. Among frogs, embryos in two distantly related lineages develop in the skin of the maternal parents' backs; they are born either as advanced larvae or fully metamorphosed froglets, depending on the species. In other frogs, and in salamanders and caecilians, viviparity is intraoviductal; one lineage of salamanders includes species that are yolk dependent and born either as larvae or metamorphs, or that practice cannibalism and are born as metamorphs. Live-bearing caecilians all, so far as is known, exhaust yolk before hatching and mothers provide nutrients during the rest of the relatively long gestation period. The developing young that have maternal nutrition have a number of heterochronic changes, such as precocious development of the feeding apparatus and the gut. Furthermore, several of the fetal adaptations, such as a specialized dentition and a prolonged metamorphosis, are homoplasious and present in members of two or all three of the amphibian orders. At the same time, we know little about the developmental and functional bases for fetal adaptations, and less about the factors that drive their evolution and facilitate their maintenance.

  4. Current extinction rates of reptiles and amphibians.

    Science.gov (United States)

    Alroy, John

    2015-10-20

    There is broad concern that a mass extinction of amphibians and reptiles is now underway. Here I apply an extremely conservative Bayesian method to estimate the number of recent amphibian and squamate extinctions in nine important tropical and subtropical regions. The data stem from a combination of museum collection databases and published site surveys. The method computes an extinction probability for each species by considering its sighting frequency and last sighting date. It infers hardly any extinction when collection dates are randomized and it provides underestimates when artificial extinction events are imposed. The method also appears to be insensitive to trends in sampling; therefore, the counts it provides are absolute minimums. Extinctions or severe population crashes have accumulated steadily since the 1970s and 1980s, and at least 3.1% of frog species have already disappeared. Based on these data and this conservative method, the best estimate of the global grand total is roughly 200 extinctions. Consistent with previous results, frog losses are heavy in Latin America, which has been greatly affected by the pathogenic chytrid fungus Batrachochytrium dendrobatidis. Extinction rates are now four orders-of-magnitude higher than background, and at least another 6.9% of all frog species may be lost within the next century, even if there is no acceleration in the growth of environmental threats.

  5. Influence of ionizing radiation on Cobra (Naja haje) and Cerastes cerastes venoms: Toxicological and immunological aspects

    OpenAIRE

    Esmat A. Shaban

    2003-01-01

    The effect of gamma irradiation (15 KGy) on the Cobra Naja haje and Cerastes cerastes venoms toxicity and immunogenicity was evaluated. Irradiated venoms were at least 28.1% less toxic than non-irradiated venoms. However the antigenic response was not changed as judged by the capacity of irradiated venoms to react with polyvalent antivenom horse serum. The immunodiffusion method showed identity between irradiated and non-irradiated samples. The effect of gamma radiation on some venom enzymes ...

  6. Venom landscapes: mining the complexity of spider venoms via a combined cDNA and mass spectrometric approach.

    Science.gov (United States)

    Escoubas, Pierre; Sollod, Brianna; King, Glenn F

    2006-05-01

    The complexity of Australian funnel-web spider venoms has been explored via the combined use of MALDI-TOF mass spectrometry coupled with chromatographic separation and the analysis of venom-gland cDNA libraries. The results show that these venoms are far more complex than previously realized. We show that the venoms of Australian funnel-web spiders contain many hundreds of peptides that follow a bimodal distribution, with about 75% of the peptides having a mass of 3000-5000 Da. The mass spectral data were validated by matching the experimentally observed masses with those predicted from peptide sequences derived from analysis of venom-gland cDNA libraries. We show that multiple isoforms of these peptides are found in small chromatographic windows, which suggests that the wide distribution of close molecular weights among the chromatographic fractions probably reflects a diversity of structures and physicochemical properties. The combination of all predicted and measured parameters permits the interpretation of three-dimensional 'venom landscapes' derived from LC-MALDI analysis. We propose that these venom landscapes might have predictive value for the discovery of various groups of pharmacologically distinct toxins in complex venoms.

  7. Snake venomics of monocled cobra (Naja kaouthia) and investigation of human IgG response against venom toxins

    DEFF Research Database (Denmark)

    Laustsen, Andreas Hougaard; Gutiérrez, José María; Lohse, Brian

    2015-01-01

    /cardiotoxins. IgGs isolated from a person who had repeatedly self-immunized with a variety of snake venoms were immunoprofiled by ELISA against all venom fractions. Stronger responses against larger toxins, but lower against the most critical α-neurotoxins were obtained. As expected, no neutralization potential...

  8. A Study on Major Components of Bee Venom Using Electrophoresis

    Directory of Open Access Journals (Sweden)

    Lee, Jin-Seon

    2000-12-01

    Full Text Available This study was designed to study on major components of various Bee Venom(Bee Venom by electrical stimulation in Korea; K-BV I, Bee Venom by Microwave stimulation in Korea; K -BV II, 0.5rng/ml, Fu Yu Pharmaceutical Factory, China; C-BV, 1mg /ml, Monmouth Pain Institute, Inc., U.S.A.; A-BV using Electrophoresis. The results were summarized as follows: 1. In 1:4000 Bee Venom solution rate, the band was not displayed distinctly usmg Electrophoresis. But in 1: 1000, the band showed clearly. 2. The results of Electrophoresis at solution rate 1:1000, K-BV I and K-BVII showed similar band. 3. The molecular weight of Phospholipase A2 was known as 19,000 but its band was seen at 17,000 in Electrophoresis. 4. Protein concentration of Bee Venom by Lowry method was different at solution rate 1:4000 ; C-BV was 250μg/ml, K-BV I was 190μg/ml, K-BV Ⅱ was 160μg/ml and C-BV was 45μg/ml. 5. Electrophoresis method was unuseful for analysis of Bee Venom when solution rate is above 1:4000 but Protein concentration of Bee Venom by Lowry method was possible. These data from the study can be applied to establish the standard measurement of Bee Venom and prevent pure bee venom from mixing of another components. I think it is desirable to study more about safety of Bee Venom as time goes by.

  9. Brown spider (Loxosceles genus) venom toxins: tools for biological purposes.

    Science.gov (United States)

    Chaim, Olga Meiri; Trevisan-Silva, Dilza; Chaves-Moreira, Daniele; Wille, Ana Carolina M; Ferrer, Valéria Pereira; Matsubara, Fernando Hitomi; Mangili, Oldemir Carlos; da Silveira, Rafael Bertoni; Gremski, Luiza Helena; Gremski, Waldemiro; Senff-Ribeiro, Andrea; Veiga, Silvio Sanches

    2011-03-01

    Venomous animals use their venoms as tools for defense or predation. These venoms are complex mixtures, mainly enriched of proteic toxins or peptides with several, and different, biological activities. In general, spider venom is rich in biologically active molecules that are useful in experimental protocols for pharmacology, biochemistry, cell biology and immunology, as well as putative tools for biotechnology and industries. Spider venoms have recently garnered much attention from several research groups worldwide. Brown spider (Loxosceles genus) venom is enriched in low molecular mass proteins (5-40 kDa). Although their venom is produced in minute volumes (a few microliters), and contain only tens of micrograms of protein, the use of techniques based on molecular biology and proteomic analysis has afforded rational projects in the area and permitted the discovery and identification of a great number of novel toxins. The brown spider phospholipase-D family is undoubtedly the most investigated and characterized, although other important toxins, such as low molecular mass insecticidal peptides, metalloproteases and hyaluronidases have also been identified and featured in literature. The molecular pathways of the action of these toxins have been reported and brought new insights in the field of biotechnology. Herein, we shall see how recent reports describing discoveries in the area of brown spider venom have expanded biotechnological uses of molecules identified in these venoms, with special emphasis on the construction of a cDNA library for venom glands, transcriptome analysis, proteomic projects, recombinant expression of different proteic toxins, and finally structural descriptions based on crystallography of toxins.

  10. Brown Spider (Loxosceles genus Venom Toxins: Tools for Biological Purposes

    Directory of Open Access Journals (Sweden)

    Andrea Senff-Ribeiro

    2011-03-01

    Full Text Available Venomous animals use their venoms as tools for defense or predation. These venoms are complex mixtures, mainly enriched of proteic toxins or peptides with several, and different, biological activities. In general, spider venom is rich in biologically active molecules that are useful in experimental protocols for pharmacology, biochemistry, cell biology and immunology, as well as putative tools for biotechnology and industries. Spider venoms have recently garnered much attention from several research groups worldwide. Brown spider (Loxosceles genus venom is enriched in low molecular mass proteins (5–40 kDa. Although their venom is produced in minute volumes (a few microliters, and contain only tens of micrograms of protein, the use of techniques based on molecular biology and proteomic analysis has afforded rational projects in the area and permitted the discovery and identification of a great number of novel toxins. The brown spider phospholipase-D family is undoubtedly the most investigated and characterized, although other important toxins, such as low molecular mass insecticidal peptides, metalloproteases and hyaluronidases have also been identified and featured in literature. The molecular pathways of the action of these toxins have been reported and brought new insights in the field of biotechnology. Herein, we shall see how recent reports describing discoveries in the area of brown spider venom have expanded biotechnological uses of molecules identified in these venoms, with special emphasis on the construction of a cDNA library for venom glands, transcriptome analysis, proteomic projects, recombinant expression of different proteic toxins, and finally structural descriptions based on crystallography of toxins.

  11. Effect of suramin on myotoxicity of some crotalid snake venoms

    Directory of Open Access Journals (Sweden)

    E.Z. Arruda

    2002-06-01

    Full Text Available We investigated the protective effect of suramin, an enzyme inhibitor and an uncoupler of G protein from receptors, on the myotoxic activity in mice of different crotalid snake venoms (A.c. laticinctus, C.v. viridis, C.d. terrificus, B. jararacussu, B. moojeni, B. alternatus, B. jararaca, L. muta. Myotoxicity was evaluated in vivo by injecting im the venoms (0.5 or 1.0 mg/kg dissolved in physiological saline solution (0.1 ml and measuring plasma creatine kinase (CK activity. Two experimental approaches were used in mice (N = 5 for each group. In protocol A, 1 mg of each venom was incubated with 1.0 mg suramin (15 min, 37ºC, in vitro, and then injected im into the mice at a dose of 1.0 mg/kg (in vivo. In protocol B, venoms, 1.0 mg/kg, were injected im 15 min prior to suramin (1.0 mg/kg, iv. Before and 2 h after the im injection blood was collected by orbital puncture. Plasma was separated and stored at 4ºC for determination of CK activity using a diagnostic kit from Sigma. Preincubation of some venoms (C.v. viridis, A.c. laticinctus, C.d. terrificus and B. jararacussu with suramin reduced (37-76% the increase in plasma CK, except for B. alternatus, B. jararaca or L. muta venoms. Injection of suramin after the venom partially protected (34-51% against the myotoxicity of B. jararacussu, A.c. laticinctus and C.d. terrificus venom, and did not protect against C.v. viridis, L. muta, B. moojeni, B. alternatus or B. jararaca venoms. These results show that suramin has an antimyotoxic effect against some, but not all the North and South American crotalid snake venoms studied here.

  12. Venom immunotherapy improves health-related quality of life in patients allergic to yellow jacket venom

    NARCIS (Netherlands)

    Elberink, JNGO; de Monchy, JGR; van der Heide, S; Guyatt, GH; Dubois, AEJ

    2002-01-01

    Background: Venom immunotherapy (VIT) is effective in preventing anaphylactic reactions after insect stings. The effect of VIT on health-related quality of life (HRQL) was studied to evaluate whether this treatment is of importance to patients. Objective: We compared HRQL outcomes measured with a di

  13. Epithelium specific ETS transcription factor, ESE-3, of Protobothrops flavoviridis snake venom gland transactivates the promoters of venom phospholipase A2 isozyme genes.

    Science.gov (United States)

    Nakamura, Hitomi; Murakami, Tatsuo; Hattori, Shosaku; Sakaki, Yoshiyuki; Ohkuri, Takatoshi; Chijiwa, Takahito; Ohno, Motonori; Oda-Ueda, Naoko

    2014-12-15

    Protobothrops flavoviridis (habu) (Crotalinae, Viperidae) is a Japanese venomous snake, and its venom contains the enzymes with a variety of physiological activities. The phospholipases A2 (PLA2s) are the major components and exert various toxic effects. They are expressed abundantly in the venom gland. It is thought that the venom gland-specific transcription factors play a key role for activation of PLA2 genes specifically expressed in the venom gland. Thus, the full-length cDNA library for P. flavoviridis venom gland after milking of the venom was made to explore the transcription factors therein. As a result, three cDNAs encoding epithelium-specific ETS transcription factors (ESE)-1, -2, and -3 were obtained. Among them, ESE-3 was specifically expressed in the venom gland and activated the proximal promoters of venom PLA2 genes, which are possibly regarded as the representatives of the venom gland-specific protein genes in P. flavoviridis. Interestingly, the binding specificity of ESE-3 to the ETS binding motif located near TATA box is well correlated with transcriptional activities for the venom PLA2 genes. This is the first report that venom gland-specific transcription factor could actually activate the promoters of the venom protein genes.

  14. Venom physiology and composition in a litter of Common Death Adders (Acanthophis antarcticus) and their parents.

    Science.gov (United States)

    Pintor, Anna F V; Winter, Kelly L; Krockenberger, Andrew K; Seymour, Jamie E

    2011-01-01

    Metabolic expenditure has been shown to increase abruptly in several snake species directly after venom expenditure, while the later stages of venom replenishment seem to involve minor costs. This study examines the dependence of increases in metabolic rate following venom expenditure on the stage of venom replenishment that the venom producing tissue is in at the time of venom extraction in the Common Death Adder, Acanthophis antarcticus. Potential changes in venom composition during venom replenishment are also explored to elucidate whether replenishment is achieved via low rates of synthesis of all venom components or by non-parallel protein production, i.e. initial production of some venom components and subsequent synthesis of others. The results of this study indicate that venom expenditure is followed by a sudden increase in metabolic rate when snakes have previously not expended venom for at least two days, suggesting that repetitive venom expenditure does not further increase the activity of venom gland tissue in this initial time period but that a second upregulation occurs when the tissue is past the initial activation stage. In addition, venom composition appears to remain constant during replenishment within an individual, while substantial variations can be observed even between siblings.

  15. Amphibian skin may select for rare environmental microbes.

    Science.gov (United States)

    Walke, Jenifer B; Becker, Matthew H; Loftus, Stephen C; House, Leanna L; Cormier, Guy; Jensen, Roderick V; Belden, Lisa K

    2014-11-01

    Host-microbe symbioses rely on the successful transmission or acquisition of symbionts in each new generation. Amphibians host a diverse cutaneous microbiota, and many of these symbionts appear to be mutualistic and may limit infection by the chytrid fungus, Batrachochytrium dendrobatidis, which has caused global amphibian population declines and extinctions in recent decades. Using bar-coded 454 pyrosequencing of the 16S rRNA gene, we addressed the question of symbiont transmission by examining variation in amphibian skin microbiota across species and sites and in direct relation to environmental microbes. Although acquisition of environmental microbes occurs in some host-symbiont systems, this has not been extensively examined in free-living vertebrate-microbe symbioses. Juvenile bullfrogs (Rana catesbeiana), adult red-spotted newts (Notophthalmus viridescens), pond water and pond substrate were sampled at a single pond to examine host-specificity and potential environmental transmission of microbiota. To assess population level variation in skin microbiota, adult newts from two additional sites were also sampled. Cohabiting bullfrogs and newts had distinct microbial communities, as did newts across the three sites. The microbial communities of amphibians and the environment were distinct; there was very little overlap in the amphibians' core microbes and the most abundant environmental microbes, and the relative abundances of OTUs that were shared by amphibians and the environment were inversely related. These results suggest that, in a host species-specific manner, amphibian skin may select for microbes that are generally in low abundance in the environment.

  16. Modeling effects of conservation grassland losses on amphibian habitat

    Science.gov (United States)

    Mushet, David M.; Neau, Jordan L.; Euliss, Ned H.

    2014-01-01

    Amphibians provide many ecosystem services valued by society. However, populations have declined globally with most declines linked to habitat change. Wetlands and surrounding terrestrial grasslands form habitat for amphibians in the North American Prairie Pothole Region (PPR). Wetland drainage and grassland conversion have destroyed or degraded much amphibian habitat in the PPR. However, conservation grasslands can provide alternate habitat. In the United States, the Conservation Reserve Program (CRP) is the largest program maintaining grasslands on agricultural lands. We used an ecosystem services model (InVEST) parameterized for the PPR to quantify amphibian habitat over a six-year period (2007–2012). We then quantified changes in availability of amphibian habitat under various land-cover scenarios representing incremental losses (10%, 25%, 50%, 75%, and 100%) of CRP grasslands from 2012 levels. The area of optimal amphibian habitat in the four PPR ecoregions modeled (i.e., Northern Glaciated Plains, Northwestern Glaciated Plains, Lake Agassiz Plain, Des Moines Lobe) declined by approximately 22%, from 3.8 million ha in 2007 to 2.9 million ha in 2012. These losses were driven by the conversion of CRP grasslands to croplands, primarily for corn and soybean production. Our modeling identified an additional 0.8 million ha (26%) of optimal amphibian habitat that would be lost if remaining CRP lands are returned to crop production. An economic climate favoring commodity production over conservation has resulted in substantial losses of amphibian habitat across the PPR that will likely continue into the future. Other regions of the world face similar challenges to maintaining amphibian habitats.

  17. Facility design and associated services for the study of amphibians.

    Science.gov (United States)

    Browne, Robert K; Odum, R Andrew; Herman, Timothy; Zippel, Kevin

    2007-01-01

    The role of facilities and associated services for amphibians has recently undergone diversification. Amphibians traditionally used as research models adjust well to captivity and thrive with established husbandry techniques. However, it is now necessary to maintain hundreds of novel amphibian species in captive breeding, conservation research, and biomedical research programs. These diverse species have a very wide range of husbandry requirements, and in many cases the ultimate survival of threatened species will depend on captive populations. Two critical factors have emerged in the maintenance of amphibians, stringent quarantine and high-quality water. Because exotic diseases such as chytridiomycosis have devastated both natural and captive populations of amphibians, facilities must provide stringent quarantine. The provision of high-quality water is also essential to maintain amphibian health and condition due to the intimate physiological relationship of amphibians to their aquatic environment. Fortunately, novel technologies backed by recent advances in the scientific knowledge of amphibian biology and disease management are available to overcome these challenges. For example, automation can increase the reliability of quarantine and maintain water quality, with a corresponding decrease in handling and the associated disease-transfer risk. It is essential to build facilities with appropriate nontoxic waterproof materials and to provide quarantined amphibian rooms for each population. Other spaces and services include live feed rooms, quarantine stations, isolation rooms, laboratory space, technical support systems, reliable energy and water supplies, high-quality feed, and security. Good husbandry techniques must include reliable and species-specific management by trained staff members who receive support from the administration. It is possible to improve husbandry techniques for many species by sharing knowledge through common information systems. Overall

  18. Reptiles and Amphibians of Fairchild Air Force Base, WA

    Science.gov (United States)

    2013-05-10

    ER D C/ CE R L TR -1 3 -5 Reptiles and Amphibians of Fairchild Air Force Base, WA C on st ru ct io n E n gi n ee ri n g R es ea rc...online library at http://acwc.sdp.sirsi.net/client/default. ERDC/CERL TR-13-5 May 2013 Reptiles and Amphibians of Fairchild Air Force Base, WA...Washington, DC 20314-1000 ERDC/CERL TR-13-5 ii Abstract Many reptile and amphibian (collectively termed “herpetofauna”) populations are declining at a

  19. Zoonotic diseases associated with reptiles and amphibians: an update.

    Science.gov (United States)

    Mitchell, Mark A

    2011-09-01

    Reptiles and amphibians are popular as pets. There are increased concerns among public health officials because of the zoonotic potential associated with these animals. Encounters with reptiles and amphibians are also on the rise in the laboratory setting and with wild animals; in both of these practices, there is also an increased likelihood for exposure to zoonotic pathogens. It is important that veterinarians remain current with the literature as it relates to emerging and reemerging zoonotic diseases attributed to reptiles and amphibians so that they can protect themselves, their staff, and their clients from potential problems.

  20. ASSESSMENT OF THE RISK OF SOLAR ULTRAVIOLET RADIATION TO AMPHIBIANS. II: IN SITU CHARACTERIZATION OF SOLAR ULTRAVIOLET RADIATION IN AMPHIBIAN HABITATS

    Science.gov (United States)

    Ultraviolet B (UVB) radiation has been hypothesized as a potential cause of amphibian population declines and increased incidences of malformations. Realistic studies documenting UV irradiance or dose have rarely been conducted in wetlands used by amphibians. We demonstrate that ...

  1. Chironex fleckeri (Box Jellyfish) Venom Proteins

    Science.gov (United States)

    Brinkman, Diane L.; Konstantakopoulos, Nicki; McInerney, Bernie V.; Mulvenna, Jason; Seymour, Jamie E.; Isbister, Geoffrey K.; Hodgson, Wayne C.

    2014-01-01

    The box jellyfish Chironex fleckeri produces extremely potent and rapid-acting venom that is harmful to humans and lethal to prey. Here, we describe the characterization of two C. fleckeri venom proteins, CfTX-A (∼40 kDa) and CfTX-B (∼42 kDa), which were isolated from C. fleckeri venom using size exclusion chromatography and cation exchange chromatography. Full-length cDNA sequences encoding CfTX-A and -B and a third putative toxin, CfTX-Bt, were subsequently retrieved from a C. fleckeri tentacle cDNA library. Bioinformatic analyses revealed that the new toxins belong to a small family of potent cnidarian pore-forming toxins that includes two other C. fleckeri toxins, CfTX-1 and CfTX-2. Phylogenetic inferences from amino acid sequences of the toxin family grouped CfTX-A, -B, and -Bt in a separate clade from CfTX-1 and -2, suggesting that the C. fleckeri toxins have diversified structurally and functionally during evolution. Comparative bioactivity assays revealed that CfTX-1/2 (25 μg kg−1) caused profound effects on the cardiovascular system of anesthetized rats, whereas CfTX-A/B elicited only minor effects at the same dose. Conversely, the hemolytic activity of CfTX-A/B (HU50 = 5 ng ml−1) was at least 30 times greater than that of CfTX-1/2. Structural homology between the cubozoan toxins and insecticidal three-domain Cry toxins (δ-endotoxins) suggests that the toxins have a similar pore-forming mechanism of action involving α-helices of the N-terminal domain, whereas structural diversification among toxin members may modulate target specificity. Expansion of the cnidarian toxin family therefore provides new insights into the evolutionary diversification of box jellyfish toxins from a structural and functional perspective. PMID:24403082

  2. Scyphozoan jellyfish venom metalloproteinases and their role in the cytotoxicity.

    Science.gov (United States)

    Lee, Hyunkyoung; Jung, Eun-sun; Kang, Changkeun; Yoon, Won Duk; Kim, Jong-Shu; Kim, Euikyung

    2011-09-01

    The present study, for the first time, comparatively investigated the enzymatic activities (proteases and hyaluronidases) in the venoms of four Scyphozoan jellyfish species, including Nemopilema nomurai, Rhopilema esculenta, Cyanea nozakii, and Aurelia aurita. For this, various zymographic analyses were performed using assay specific substrates. Interestingly, all the four jellyfish venoms showed gelatinolytic, caseinolytic, and fibrinolytic activities, each of which contains a multitude of enzyme components with molecular weights between 17 and 130 kDa. These four jellyfish venoms demonstrated a huge variation in their proteolytic activities in quantitative and qualitative manner depending on the species. Most of these enzymatic activities were disappeared by the treatment of 1,10-phenanthroline, suggesting they might be belonged to metalloproteinases. Toxicological significance of these venom proteases was examined by comparing their proteolytic activity and the cytotoxicity in NIH 3T3 cells. The relative cytotoxic potency was C. nozakii > N. nomurai > A. aurita > R. esculenta. The cytotoxicity of jellyfish venom shows a positive correlation with its overall proteolytic activity. The metalloproteinases appear to play an important role in the induction of jellyfish venom toxicities. In conclusion, the present report proposes a novel finding of Scyphozoan jellyfish venom metalloproteinases and their potential role in the cytotoxicity.

  3. Micrurus snake venoms activate human complement system and generate anaphylatoxins

    Directory of Open Access Journals (Sweden)

    Tanaka Gabriela D

    2012-01-01

    Full Text Available Abstract Background The genus Micrurus, coral snakes (Serpentes, Elapidae, comprises more than 120 species and subspecies distributed from the south United States to the south of South America. Micrurus snake bites can cause death by muscle paralysis and further respiratory arrest within a few hours after envenomation. Clinical observations show mainly neurotoxic symptoms, although other biological activities have also been experimentally observed, including cardiotoxicity, hemolysis, edema and myotoxicity. Results In the present study we have investigated the action of venoms from seven species of snakes from the genus Micrurus on the complement system in in vitro studies. Several of the Micrurus species could consume the classical and/or the lectin pathways, but not the alternative pathway, and C3a, C4a and C5a were generated in sera treated with the venoms as result of this complement activation. Micrurus venoms were also able to directly cleave the α chain of the component C3, but not of the C4, which was inhibited by 1,10 Phenanthroline, suggesting the presence of a C3α chain specific metalloprotease in Micrurus spp venoms. Furthermore, complement activation was in part associated with the cleavage of C1-Inhibitor by protease(s present in the venoms, which disrupts complement activation control. Conclusion Micrurus venoms can activate the complement system, generating a significant amount of anaphylatoxins, which may assist due to their vasodilatory effects, to enhance the spreading of other venom components during the envenomation process.

  4. [Drug or plant substances which antagonize venoms or potentiate antivenins].

    Science.gov (United States)

    Chippaux, J P; Rakotonirina, V S; Rakotonirina, A; Dzikouk, G

    1997-01-01

    Dendroaspis jamesoni (Elapidae) and Echis oceliatus (Viperidae) are responsible for most of severe evenomation in Cameroon. Toxicity of venoms of these two species has been measured using mice according to the method of Spearman & Kàrber. The effect on experimental envenomation of various drugs (atropine, promethazine, neostigmine, hydrocortisone, pentosane sulfuric polyester, heparin, tranexamic acid and aminocaproic acid) and plant extracts (Schumanniophyton magnificum, Bidens pilosa, Securidaca longepedunculata and Garcinia lucida) has been observed associated or not with the antivenom lpser Afrique (SAV). The venom of D. jamesoni contains neurotoxins agonizing and antagonising acetylcholine. The toxicity of the venom did not depend on the route of injection. Atropine, promethazine, neostigmine and hydrocortisone protected animals against a venom dose up to 2 LD50. Moreover, atropine and promethazine potentiated the SAV. Similar results have been obtained with extracts from S. magnificum and B. pilosa. The venom of E. ocellatus induces haemorrhage and necrosis. The toxicity increased by 3-fold when the venom was injected through intravenous or intraperitoneal route, compared to intramuscular route. Pentosane sulfuric polyester and tranexamic acid protected mice against doses up to 3 LD50. Pentosane sulfuric polyester, hydrocortisone, heparin and aminocaproic acid increased the SAV protective titre by 50%. However, tried plant extracts weakly antagonised the venom and did not potentiate the SAV.

  5. Effects of Animal Venoms and Toxins on Hallmarks of Cancer.

    Science.gov (United States)

    Chaisakul, Janeyuth; Hodgson, Wayne C; Kuruppu, Sanjaya; Prasongsook, Naiyarat

    2016-01-01

    Animal venoms are a cocktail of proteins and peptides, targeting vital physiological processes. Venoms have evolved to assist in the capture and digestion of prey. Key venom components often include neurotoxins, myotoxins, cardiotoxins, hematoxins and catalytic enzymes. The pharmacological activities of venom components have been investigated as a source of potential therapeutic agents. Interestingly, a number of animal toxins display profound anticancer effects. These include toxins purified from snake, bee and scorpion venoms effecting cancer cell proliferation, migration, invasion, apoptotic activity and neovascularization. Indeed, the mechanism behind the anticancer effect of certain toxins is similar to that of agents currently used in chemotherapy. For example, Lebein is a snake venom disintegrin which generates anti-angiogenic effects by inhibiting vascular endothelial growth factors (VEGF). In this review article, we highlight the biological activities of animal toxins on the multiple steps of tumour formation or hallmarks of cancer. We also discuss recent progress in the discovery of lead compounds for anticancer drug development from venom components.

  6. Neutralization of Apis mellifera bee venom activities by suramin.

    Science.gov (United States)

    El-Kik, Camila Z; Fernandes, Fabrício F A; Tomaz, Marcelo Amorim; Gaban, Glauco A; Fonseca, Tatiane F; Calil-Elias, Sabrina; Oliveira, Suellen D S; Silva, Claudia L M; Martinez, Ana Maria Blanco; Melo, Paulo A

    2013-06-01

    In this work we evaluated the ability of suramin, a polysulfonated naphthylurea derivative, to antagonize the cytotoxic and enzymatic effects of the crude venom of Apis mellifera. Suramin was efficient to decrease the lethality in a dose-dependent way. The hemoconcentration caused by lethal dose injection of bee venom was abolished by suramin (30 μg/g). The edematogenic activity of the venom (0.3 μg/g) was antagonized by suramin (10 μg/g) in all treatment protocols. The changes in the vascular permeability caused by A. mellifera (1 μg/g) venom were inhibited by suramin (30 μg/g) in the pre- and posttreatment as well as when the venom was preincubated with suramin. In addition, suramin also inhibited cultured endothelial cell lesion, as well as in vitro myotoxicity, evaluated in mouse extensor digitorum longus muscle, which was inhibited by suramin (10 and 25 μM), decreasing the rate of CK release, showing that suramin protected the sarcolemma against damage induced by components of bee venom (2.5 μg/mL). Moreover, suramin inhibited the in vivo myotoxicity induced by i.m. injection of A. mellifera venom in mice (0.5 μg/g). The analysis of the area under the plasma CK vs. time curve showed that preincubation, pre- and posttreatment with suramin (30 μg/g) inhibited bee venom myotoxic activity in mice by about 89%, 45% and 40%, respectively. Suramin markedly inhibited the PLA2 activity in a concentration-dependent way (1-30 μM). Being suramin a polyanion molecule, the effects observed may be due to the interaction of its charges with the polycation components present in A. mellifera bee venom.

  7. Immobilizing and lethal effects of spider venoms on the cockroach and the common mealbeetle.

    Science.gov (United States)

    Friedel, T; Nentwig, W

    1989-01-01

    Immobilizing and lethal effects of the venoms obtained from six spider species (Brachypelma albopilosum, Atrax robustus, Cupiennius salei, Selenops mexicanus, Tegenaria atrica, Argiope bruennichi) were tested on Blatta orientalis (cockroach) and Tenebrio molitor (common mealbeetle). The immobilizing effects were quantified by measuring insect locomotor activity in circle arenas observed over 72 hr after venom injection. Both insect species showed cramps, quivering and jerking of the limbs as well as flaccid paralysis after venom injection. Through relative toxicity of the venoms tested is the same in T. molitor and B. orientalis, T. molitor is absolutely less sensitive to spider venoms. The effects on locomotor activity show time characteristics specific for each venom. A dependence of the venom paralyzing effects on insect locomotor activity, low intensity of the initial excitatory phase of the venom effects and partial recovery of the insects was found with A. bruennichi and T. atrica venom. The maximal venom yields of A. bruennichi and S. mexicanus are not lethal to B. orientalis, indicating that the mere immobilizing effects of spider venoms are far more crucial to prey capture than their lethal effects. The contribution of a variety of differently acting neurotoxic components in spider venoms to the observed venom effects on insects and the significance of the venoms in spider nutrition, hunting behaviour and ecology are discussed.

  8. Production and packaging of a biological arsenal: evolution of centipede venoms under morphological constraint.

    Science.gov (United States)

    Undheim, Eivind A B; Hamilton, Brett R; Kurniawan, Nyoman D; Bowlay, Greg; Cribb, Bronwen W; Merritt, David J; Fry, Bryan G; King, Glenn F; Venter, Deon J

    2015-03-31

    Venom represents one of the most extreme manifestations of a chemical arms race. Venoms are complex biochemical arsenals, often containing hundreds to thousands of unique protein toxins. Despite their utility for prey capture, venoms are energetically expensive commodities, and consequently it is hypothesized that venom complexity is inversely related to the capacity of a venomous animal to physically subdue prey. Centipedes, one of the oldest yet least-studied venomous lineages, appear to defy this rule. Although scutigeromorph centipedes produce less complex venom than those secreted by scolopendrid centipedes, they appear to rely heavily on venom for prey capture. We show that the venom glands are large and well developed in both scutigerid and scolopendrid species, but that scutigerid forcipules lack the adaptations that allow scolopendrids to inflict physical damage on prey and predators. Moreover, we reveal that scolopendrid venom glands have evolved to accommodate a much larger number of secretory cells and, by using imaging mass spectrometry, we demonstrate that toxin production is heterogeneous across these secretory units. We propose that the differences in venom complexity between centipede orders are largely a result of morphological restrictions of the venom gland, and consequently there is a strong correlation between the morphological and biochemical complexity of this unique venom system. The current data add to the growing body of evidence that toxins are not expressed in a spatially homogenous manner within venom glands, and they suggest that the link between ecology and toxin evolution is more complex than previously thought.

  9. Brown spider venom toxins interact with cell surface and are endocytosed by rabbit endothelial cells.

    Science.gov (United States)

    Nowatzki, Jenifer; de Sene, Reginaldo Vieira; Paludo, Katia Sabrina; Veiga, Silvio Sanches; Oliver, Constance; Jamur, Maria Célia; Nader, Helena Bonciani; Trindade, Edvaldo S; Franco, Célia Regina C

    2010-09-15

    Bites from the Loxosceles genus (brown spiders) cause severe clinical symptoms, including dermonecrotic injury, hemorrhage, hemolysis, platelet aggregation and renal failure. Histological findings of dermonecrotic lesions in animals exposed to Loxosceles intermedia venom show numerous vascular alterations. Study of the hemorrhagic consequences of the venom in endothelial cells has demonstrated that the degeneration of blood vessels results not only from degradation of the extracellular matrix molecule or massive leukocyte infiltration, but also from a direct and primary activity of the venom on endothelial cells. Exposure of an endothelial cell line in vitro to L. intermedia venom induce morphological alterations, such as cell retraction and disadhesion to the extracellular matrix. The aim of the present study was to investigate the interaction between the venom toxins and the endothelial cell surface and their possible internalization, in order to illuminate the information about the deleterious effect triggered by venom. After treating endothelial cells with venom toxins, we observed that the venom interacts with cell surface. Venom treatment also can cause a reduction of cell surface glycoconjugates. When cells were permeabilized, it was possible to verify that some venom toxins were internalized by the endothelial cells. The venom internalization involves endocytic vesicles and the venom was detected in the lysosomes. However, no damage to lysosomal integrity was observed, suggesting that the cytotoxic effect evoked by L. intermedia venom on endothelial cells is not mediated by venom internalization.

  10. An alternative framework for responding to the amphibian crisis

    Science.gov (United States)

    Muths, Erin L.; Fisher, Robert N.

    2017-01-01

    Volumes of data illustrate the severity of the crisis affecting amphibians, where > 32% of amphibians worldwide are threatened with declining populations. Although there have been isolated victories, the current approach to the issue is unsuccessful. We suggest that a radically different approach, something akin to human emergency response management (i.e. the Incident Command System), is one alternative to addressing the inertia and lack of cohesion in responding to amphibian issues. We acknowledge existing efforts and the useful research that has been conducted, but we suggest that a change is warranted and that the identification of a new amphibian chytrid provides the impetus for such a change. Our goal is to recognize that without a centralized effort we (collectively) are likely to fail in responding to this challenge.

  11. Conservation needs of amphibians in China:A review

    Institute of Scientific and Technical Information of China (English)

    Michael; Wai; Neng; LAU; Simon; N; STUART; Janice; S; CHANSON; Neil; A; COX; Debra; L; FISCHMAN

    2007-01-01

    The conservation status of all the amphibians in China is analyzed,and the country is shown to be a global priority for conservation in comparison to many other countries of the world.Three Chinese regions are particularly rich in amphibian diversity:Hengduan,Nanling,and Wuyi mountains.Sala-manders are more threatened than frogs and toads.Several smaller families show a high propensity to become seriously threatened:Bombinatoridae,Cryptobranchidae,Hynobiidae and Salamandridae.Like other parts of the world,stream-breeding,high-elevation forest amphibians have a much higher likeli-hood of being seriously threatened.Habitat loss,pollution,and over-harvesting are the most serious threats to Chinese amphibians.Over-harvesting is a less pervasive threat than habitat loss,but it is more likely to drive a species into rapid decline.Five conservation challenges are mentioned with recommendations for the highest priority research and conservation actions.

  12. Scientists urge enforcement of an amphibian conservation plan

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ A group of CAS biologists recently lodged an appeal, calling for initiating a national action plan as soon as possible to protect the amphibian species now struggling for their survival throughout the country.

  13. Trends in amphibian occupancy in the United States.

    Directory of Open Access Journals (Sweden)

    Michael J Adams

    Full Text Available Though a third of amphibian species worldwide are thought to be imperiled, existing assessments simply categorize extinction risk, providing little information on the rate of population losses. We conducted the first analysis of the rate of change in the probability that amphibians occupy ponds and other comparable habitat features across the United States. We found that overall occupancy by amphibians declined 3.7% annually from 2002 to 2011. Species that are Red-listed by the International Union for Conservation of Nature (IUCN declined an average of 11.6% annually. All subsets of data examined had a declining trend including species in the IUCN Least Concern category. This analysis suggests that amphibian declines may be more widespread and severe than previously realized.

  14. FACTORS IMPLICATED IN AMPHIBIAN POPULATION DECLINES IN THE UNITED STATES

    Science.gov (United States)

    This study identified the factors responsible for the decline of native amphibians in the U.S. The type of land use, the introduction of exotic animal species, and chemical contamination were identified as the most likely causes of decline.

  15. Trends in amphibian occupancy in the United States.

    Science.gov (United States)

    Adams, Michael J; Miller, David A W; Muths, Erin; Corn, Paul Stephen; Grant, Evan H Campbell; Bailey, Larissa L; Fellers, Gary M; Fisher, Robert N; Sadinski, Walter J; Waddle, Hardin; Walls, Susan C

    2013-01-01

    Though a third of amphibian species worldwide are thought to be imperiled, existing assessments simply categorize extinction risk, providing little information on the rate of population losses. We conducted the first analysis of the rate of change in the probability that amphibians occupy ponds and other comparable habitat features across the United States. We found that overall occupancy by amphibians declined 3.7% annually from 2002 to 2011. Species that are Red-listed by the International Union for Conservation of Nature (IUCN) declined an average of 11.6% annually. All subsets of data examined had a declining trend including species in the IUCN Least Concern category. This analysis suggests that amphibian declines may be more widespread and severe than previously realized.

  16. Trends in amphibian occupancy in the United States

    Science.gov (United States)

    Adams, Michael J.; Miller, David A.W.; Muths, Erin; Corn, Paul Stephen; Grant, Evan H. Campbell; Bailey, Larissa L.; Fellers, Gary M.; Fisher, Robert N.; Sadinski, Walter J.; Waddle, Hardin; Walls, Susan C.

    2013-01-01

    Though a third of amphibian species worldwide are thought to be imperiled, existing assessments simply categorize extinction risk, providing little information on the rate of population losses. We conducted the first analysis of the rate of change in the probability that amphibians occupy ponds and other comparable habitat features across the United States. We found that overall occupancy by amphibians declined 3.7% annually from 2002 to 2011. Species that are Red-listed by the International Union for Conservation of Nature (IUCN) declined an average of 11.6% annually. All subsets of data examined had a declining trend including species in the IUCN Least Concern category. This analysis suggests that amphibian declines may be more widespread and severe than previously realized.

  17. Amphibian chytrid fungus Batrachochytrium dendrobatidis in Cusuco National Park, Honduras.

    Science.gov (United States)

    Kolby, Jonathan E; Padgett-Flohr, Gretchen E; Field, Richard

    2010-11-01

    Amphibian population declines in Honduras have long been attributed to habitat degradation and pollution, but an increasing number of declines are now being observed from within the boundaries of national parks in pristine montane environments. The amphibian chytrid fungus Batrachochytrium dendrobatidis has been implicated in these declines and was recently documented in Honduras from samples collected in Pico Bonito National Park in 2003. This report now confirms Cusuco National Park, a protected cloud forest reserve with reported amphibian declines, to be the second known site of infection for Honduras. B. dendrobatidis infection was detected in 5 amphibian species: Craugastor rostralis, Duellmanohyla soralia, Lithobates maculata, Plectrohyla dasypus, and Ptychohyla hypomykter. D. soralia, P. dasypus, and P. hypomykter are listed as critically endangered in the IUCN Red List of Threatened Species and have severely fragmented or restricted distributions. Further investigations are necessary to determine whether observed infection levels indicate an active B. dendrobatidis epizootic with the potential to cause further population declines and extinction.

  18. Fish Springs NWR mammal, fish, amphibian, and reptile list

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The following is a species list for mammals, fishes, amphibians, and reptiles found on or adjacent to Fish Springs National Wildlife Refuge, as of October, 1996.

  19. Amphibian and reptile diversity of the Lahontan Valley

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report is about a survey that was done to assess the amphibian and reptile diversity of the Lahontan Valley in Nevada. The work contained in this summary can be...

  20. Coastal Resources Atlas: Long Island: REPTILES (Reptile and Amphibian Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for sea turtles, estuarine turtles, and amphibians for Long Island, New York. Vector polygons in this data...

  1. Invasive and introduced reptiles and amphibians: Chapter 28

    Science.gov (United States)

    Reed, Robert N.; Krysko, Kenneth L.; Mader, Douglas R.; Divers, Stephen J.

    2014-01-01

    Why is there a section on introduced amphibians and reptiles in this volume, and why should veterinarians care about this issue? Globally, invasive species are a major threat to the stability of native ecosystems,1,2 and amphibians and reptiles are attracting increased attention as potential invaders. Some introduced amphibians and reptiles have had a major impact (e.g., Brown Tree Snakes [Boiga irregularis] wiping out the native birds of Guam3 or Cane Toads [Rhinella marina] poisoning native Australian predators).4 For the vast majority of species, however, the ecological, economic, and sociopolitical effects of introduced amphibians and reptiles are generally poorly quantified, largely because of a lack of focused research effort rather than because such effects are nonexistent. This trend is alarming given that rates of introduction have increased exponentially in recent decades.

  2. Nationwide Abnormal Amphibian Monitoring Project : Region 3 : Interim Report 2004

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In 2000, the FWS's Environmental Contaminants Program (currently Environmental Quality Program) received funding as part of the Department of Interior's Amphibian...

  3. Nationwide Abnormal Amphibian Monitoring Project : Region 3 : Interim Report 2003

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In 2000, the FWS's Environmental Contaminants Program (currently Environmental Quality Program) received funding as part of the Department of Interior's Amphibian...

  4. Nationwide Abnormal Amphibian Monitoring Project : Region 3: 2002

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In 2000, the FWS's Environmental Contaminants Program (currently Environmental Quality Program) received funding as part of the Department of Interior's Amphibian...

  5. ALIEN SPECIES: THEIR ROLE IN AMPHIBIAN POPULATION DECLINES AND RESTORATION

    Science.gov (United States)

    Alien species (also referred to as exotic, invasive, introduced, or normative species) have been implicated as causal agents in population declines of many amphibian species. Herein, we evaluate the relative contributions of alien species and other factors in adversely affecting ...

  6. Declining amphibian populations: a global phenomenon in conservation biology

    Directory of Open Access Journals (Sweden)

    Gardner, T.

    2001-01-01

    Full Text Available The majority of the recent reductions in the Earth's biodiversity can be attributed to direct human impacts on the environment. An increasing number of studies over the last decade have reported declines in amphibian populations in areas of pristine habitat. Such reports suggest the role of indirect factors and a global effect of human activities on natural systems. Declines in amphibian populations bear significant implications for the functioning of many terrestrial ecosystems, and may signify important implications for human welfare. A wide range of candidates have been proposed to explain amphibian population declines. However, it seems likely that the relevance of each factor is dependent upon the habitat type and species in question, and that complex synergistic effects between a number of environmental factors is of critical importance. Monitoring of amphibian populations to assess the extent and cause of declines is confounded by a number of ecological and methodological limitations.

  7. Checklist of Helminth parasites of Amphibians from South America.

    Science.gov (United States)

    Campião, Karla Magalhães; Morais, Drausio Honorio; Dias, Olívia Tavares; Aguiar, Aline; Toledo, Gislayne De Melo; Tavares, Luiz Eduardo Roland; Da Silva, Reinaldo José

    2014-07-30

    Parasitological studies on helminths of amphibians in South America have increased in the past few years. Here, we present a list with summarized data published on helminths of South American amphibians from 1925 to 2012, including a list of helminth parasites, host species, and geographic records. We found 194 reports of helminths parasitizing 185 amphibian species from eleven countries: Argentina, Brazil, Chile, Colombia, Equador, French Guyana, Guyana, Paraguay, Peru, Uruguay and Venezuela. Helminth biodiversity includes 278 parasite species of the groups Acanthocephala, Nematoda, Cestoda, Monogenea and Trematoda. A list of helminth parasite species per host, and references are also presented. This contribution aims to document the biodiversity of helminth parasites in South American amphibians, as well as identify gaps in our knowledge, which in turn may guide subsequent studies. 

  8. Metabolism of pesticides after dermal exposure to amphibians

    Science.gov (United States)

    Understanding how pesticide exposure to non-target species influences toxicity is necessary to accurately assess the ecological risks these compounds pose. Aquatic, terrestrial, and arboreal amphibians are often exposed to pesticides during their agricultural application resultin...

  9. Update of reptile and amphibian lists Kern NWR complex

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document includes a list of reptiles and amphibians found at Kern NWR, and lists brief species accounts for rare sightings/species. Attached are updated lists...

  10. Conservation needs of amphibians in China: A review

    Institute of Scientific and Technical Information of China (English)

    XIE Feng; Michael Wai Neng LAU; Simon N STUART; Janice S CHANSON; Neil A COX; Debra L FISCHMAN

    2007-01-01

    The conservation status of all the amphibians in China is analyzed, and the country is shown to be a global priority for conservation in comparison to many other countries of the world. Three Chinese regions are particularly rich in amphibian diversity: Hengduan, Nanling, and Wuyi mountains. Salamanders are more threatened than frogs and toads. Several smaller families show a high propensity to become seriously threatened: Bombinatoridae, Cryptobranchidae, Hynobiidae and Salamandridae. Like other parts of the world, stream-breeding, high-elevation forest amphibians have a much higher likelihood of being seriously threatened. Habitat loss, pollution, and over-harvesting are the most serious threats to Chinese amphibians. Over-harvesting is a less pervasive threat than habitat loss, but it is more likely to drive a species into rapid decline. Five conservation challenges are mentioned with recommendations for the highest priority research and conservation actions.

  11. Abnormal amphibians on U.S. National Wildlife Refuges

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This project contains a journal article, a news release, FAQs, a fact sheet, photos, and a dataset related to a 10-year study of amphibian abnormalities on U.S....

  12. Amphibian and Reptile Research on Coldwater National Wildlife Refuge, Mississippi

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The management actions in the wildlife ponds on Coldwater National Wildlife Refuge create a highly variable and dynamic environment for amphibians and reptiles. Some...

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

    Science.gov (United States)

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

    2010-01-01

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

  14. Analysis of Fang Puncture Wound Patterns in Isfahan Province’s, Iran, Venomous and Non-Venomous Snakes

    Directory of Open Access Journals (Sweden)

    Dehghani R.1 PhD,

    2015-01-01

    Full Text Available Aims Venomous snake bites are public health problems in different parts of the world. The most specific mainstay in the treatment of envenomation is anti-venom. To treat the envenomation, it is very important to identify the offending species. This study was designed to determine the penetrating pattern of fangs and teeth of some viper snakes. Materials & Methods This descriptive study was performed on live venomous and nonvenomous snakes from 2010 till 2011. All 47 sample snakes were collected from different regions of Isfahan province such as Kashan City, Ghamsar, Niasar, Mashhad Ardehal, Taher- Abad and Khozagh. Their mouths were inspected every two weeks and development of their fangs and teeth were recorded by taking clear digital photos. Fangs and teeth patterns of samples were drawn and the results were compared. Findings One or two wounds appeared as typical fang marks at the bite site of venomous snakes while non-venomous snakes had two carved rows of small teeth. Three different teeth and fang patterns were recognized in venomous snakes which were completely different. Conclusion The fang marks of venomous snakes do not always have a common and classic pattern and there are at least 3 different patterns in Isfahan province, Iran.

  15. Initial diversification of living amphibians predated the breakup of Pangaea

    OpenAIRE

    2005-01-01

    The origin and divergence of the three living orders of amphibians (Anura, Caudata, Gymnophiona) and their main lineages are one of the most hotly debated topics in vertebrate evolution. Here, we present a robust molecular phylogeny based on the nuclear RAG1 gene as well as results from a variety of alternative independent molecular clock calibrations. Our analyses suggest that the origin and early divergence of the three living amphibian orders dates back to the Palaeozoic or early Mesozoic,...

  16. Resistance to cancer in amphibians: a role for apoptosis?

    Science.gov (United States)

    Ruben, Laurens N; Johnson, Rachel O; Clothier, Richard H; Balls, Michael

    2013-07-01

    The rarity of spontaneous cancer in amphibians, and the difficulty of inducing cancer in these lower vertebrates, suggest that they possess an effective system for resistance to the development of cancer. The first part of this narrative presents evidence for cancer resistance in amphibians, and then a variety of studies designed to help understand the physiological basis for this resistance are reviewed. Here, our emphasis is on evidence with regard to the role that apoptosis might play.

  17. The Amphibian Research and Monitoring Initiative (ARMI): 5-year report

    Science.gov (United States)

    Muths, Erin; Gallant, Alisa L.; Campbell Grant, Evan H.; Battaglin, William A.; Green, David E.; Staiger, Jennifer S.; Walls, Susan C.; Gunzburger, Margaret S.; Kearney, Rick F.

    2006-01-01

    The Amphibian Research and Monitoring Initiative (ARMI) is an innovative, multidisciplinary program that began in 2000 in response to a congressional directive for the Department of the Interior to address the issue of amphibian declines in the United States. ARMI’s formulation was cross-disciplinary, integrating U.S. Geological Survey scientists from Biology, Water, and Geography to develop a course of action (Corn and others, 2005a). The result has been an effective program with diverse, yet complementary, expertise.

  18. Recruitment of Glycosyl Hydrolase Proteins in a Cone Snail Venomous Arsenal: Further Insights into Biomolecular Features of Conus Venoms

    Directory of Open Access Journals (Sweden)

    Philippe Favreau

    2012-01-01

    Full Text Available Cone snail venoms are considered an untapped reservoir of extremely diverse peptides, named conopeptides, displaying a wide array of pharmacological activities. We report here for the first time, the presence of high molecular weight compounds that participate in the envenomation cocktail used by these marine snails. Using a combination of proteomic and transcriptomic approaches, we identified glycosyl hydrolase proteins, of the hyaluronidase type (Hyal, from the dissected and injectable venoms (“injectable venom” stands for the venom variety obtained by milking of the snails. This is in contrast to the “dissected venom”, which was obtained from dissected snails by extraction of the venom glands of a fish-hunting cone snail, Conus consors (Pionoconus clade. The major Hyal isoform, Conohyal-Cn1, is expressed as a mixture of numerous glycosylated proteins in the 50 kDa molecular mass range, as observed in 2D gel and mass spectrometry analyses. Further proteomic analysis and venom duct mRNA sequencing allowed full sequence determination. Additionally, unambiguous segment location of at least three glycosylation sites could be determined, with glycans corresponding to multiple hexose (Hex and N-acetylhexosamine (HexNAc moieties. With respect to other known Hyals, Conohyal-Cn1 clearly belongs to the hydrolase-type of Hyals, with strictly conserved consensus catalytic donor and positioning residues. Potent biological activity of the native Conohyals could be confirmed in degrading hyaluronic acid. A similar Hyal sequence was also found in the venom duct transcriptome of C. adamsonii (Textilia clade, implying a possible widespread recruitment of this enzyme family in fish-hunting cone snail venoms. These results provide the first detailed Hyal sequence characterized from a cone snail venom, and to a larger extent in the Mollusca phylum, thus extending our knowledge on this protein family and its evolutionary selection in marine snail venoms.

  19. Recombinant phospholipase A1 (Ves v 1 from yellow jacket venom for improved diagnosis of hymenoptera venom hypersensitivity

    Directory of Open Access Journals (Sweden)

    Grunwald Thomas

    2010-04-01

    Full Text Available Abstract Background Hymenoptera venoms are known to cause life-threatening IgE-mediated anaphylactic reactions in allergic individuals. Proper diagnosis of hymenoptera venom allergy using venom extracts is severely affected by molecular cross-reactivities. Although non-glycosylated marker allergens would facilitate the identification of the culprit venom, the major allergen phospholipase A1 (Ves v 1 from yellow jacket venom (YJV remained unavailable so far. Methods Expression of Ves v 1 as wild type and enzymatically inactivated mutant and Ves v 5 in insect cells yielded soluble proteins that were purified via affinity chromatography. Functionality of the recombinant allergens was assessed by enzymatic and biophysical analyses as well as basophil activation tests. Diagnostic relevance was addressed by ELISA-based analyses of sera of YJV-sensitized patients. Results Both major allergens Ves v 1 and Ves v 5 could be produced in insect cells in secreted soluble form. The recombinant proteins exhibited their particular biochemical and functional characteristics and were capable for activation of human basophils. Assessment of IgE reactivity of sera of YJV-sensitized and double-sensitized patients emphasised the relevance of Ves v 1 in hymenoptera venom allergy. In contrast to the use of singular molecules the combined use of both molecules enabled a reliable assignment of sensitisation to YJV for more than 90% of double-sensitised patients. Conclusions The recombinant availability of Ves v 1 from yellow jacket venom will contribute to a more detailed understanding of the molecular and allergological mechanisms of insect venoms and may provide a valuable tool for diagnostic and therapeutic approaches in hymenoptera venom allergy.

  20. Spider-Venom Peptides as Bioinsecticides

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    Glenn F. King

    2012-03-01

    Full Text Available Over 10,000 arthropod species are currently considered to be pest organisms. They are estimated to contribute to the destruction of ~14% of the world’s annual crop production and transmit many pathogens. Presently, arthropod pests of agricultural and health significance are controlled predominantly through the use of chemical insecticides. Unfortunately, the widespread use of these agrochemicals has resulted in genetic selection pressure that has led to the development of insecticide-resistant arthropods, as well as concerns over human health and the environment. Bioinsecticides represent a new generation of insecticides that utilise organisms or their derivatives (e.g., transgenic plants, recombinant baculoviruses, toxin-fusion proteins and peptidomimetics and show promise as environmentally-friendly alternatives to conventional agrochemicals. Spider-venom peptides are now being investigated as potential sources of bioinsecticides. With an estimated 100,000 species, spiders are one of the most successful arthropod predators. Their venom has proven to be a rich source of hyperstable insecticidal mini-proteins that cause insect paralysis or lethality through the modulation of ion channels, receptors and enzymes. Many newly characterized insecticidal spider toxins target novel sites in insects. Here we review the structure and pharmacology of these toxins and discuss the potential of this vast peptide library for the discovery of novel bioinsecticides.

  1. Antimetastatic Integrin as Inhibitors of Snake Venoms

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    Felix Rosenow

    2008-02-01

    Full Text Available Metastasis comprises several subsequent steps including local invasion and intravasation at the primary site, then their adhesion/arrest within the vessels of host organs followed by their extravasation and infiltration into the target organ stroma. In contrast to previous studies which have used aspartate-glycine-arginine (RGD peptides and antibodies against integrins, we used rare collagen- and laminin-antagonizing integrin inhibitors from snake venoms to analyze the colonization of the liver by tumor cells both by intravital microscopy and in vitro. Adhesion of liver-targeting tumor cells to the sinusoid wall components, laminin-1 and fibronectin, is essential for liver metastasis. This step is inhibited by lebein-1, but not by lebein-2 or rhodocetin. Both lebeins from the Vipera lebetina venom block integrin interactions with laminins in an RGD-independent manner. Rhodocetin is an antagonist of α2β1 integrin, a collagen receptor on many tumor cells. Subsequent to tumor cell arrest, extravasation into the liver stroma and micrometastasis are efficiently delayed by rhodocetin. This underlines the importance of α2β1 integrin interaction with the reticular collagen I-rich fibers in liver stroma. Antagonists of laminin- and collagen-binding integrins could be valuable tools to individually block the direct interactions of tumor cells with distinct matrix components of the Disse space, thereby reducing liver metastasis.

  2. Antineoplastic Effects of Honey Bee Venom

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    Mohammad Nabiuni

    2013-08-01

    Full Text Available Background: Bee venom (BV, like many other complementary medicines, has been used for thousands of years for the treatment of a range of diseases. More recently, BV is also being considered as an effective composition for the treatment of cancer. Cancer is a major worldwide problem. It is obvious that the identification of compounds that can activate apoptosis could be effective on the treatment of cancer. BV is a very complicated mixture of active peptides, enzymes, and biologically active amines. The two main components of BV are melittin and phospholipase A2 (PLA2. Of these two components, melittin, the major active ingredient of BV, has been identified to induce apoptosis and to possess anti-tumor effects. We tried to review antineoplastic effects of BV in this study. Materials and Methods: The related articles were derived from different data bases such as PubMed, Elsevier Science, and Google Scholar using keywords including bee venom, cancer, and apoptosis.Results: According to the results of this study, BV can induce apoptosis and inhibit tumor cell growth and metastasis. Results of in vivo experiments show that the anti-tumor effect of the BV is highly dependent on the manner of injection as well as the distance between the area of injection and the tumor cells.Conclusion: The results obtained from the reported studies revealed that BV has anti-cancer effects and can be used as an effective chemotherapeutic agent against tumors in the future.

  3. Why amphibians are more sensitive than mammals to xenobiotics.

    Directory of Open Access Journals (Sweden)

    Angelo Quaranta

    Full Text Available Dramatic declines in amphibian populations have been described all over the world since the 1980s. The evidence that the sensitivity to environmental threats is greater in amphibians than in mammals has been generally linked to the observation that amphibians are characterized by a rather permeable skin. Nevertheless, a numerical comparison of data of percutaneous (through the skin passage between amphibians and mammals is lacking. Therefore, in this investigation we have measured the percutaneous passage of two test molecules (mannitol and antipyrine and three heavily used herbicides (atrazine, paraquat and glyphosate in the skin of the frog Rana esculenta (amphibians and of the pig ear (mammals, by using the same experimental protocol and a simple apparatus which minimizes the edge effect, occurring when the tissue is clamped in the usually used experimental device.The percutaneous passage (P of each substance is much greater in frog than in pig. LogP is linearly related to logKow (logarithm of the octanol-water partition coefficient. The measured P value of atrazine was about 134 times larger than that of glyphosate in frog skin, but only 12 times in pig ear skin. The FoD value (Pfrog/Ppig was 302 for atrazine, 120 for antipyrine, 66 for mannitol, 29 for paraquat, and 26 for glyphosate.The differences in structure and composition of the skin between amphibians and mammals are discussed.

  4. Global amphibian declines: perspectives from the United States and beyond

    Science.gov (United States)

    Densmore, Christine L.; Cipriano, R.C.; Bruckner, A.W.; Shchelkunov, I.S.

    2011-01-01

    Over recent decades, amphibians have experienced population declines, extirpations and species-level extinctions at an alarming rate. Numerous potential etiologies for amphibian declines have been postulated including climate and habitat degradation. Other potential anthropogenic causes including overexploitation and the frequent introductions of invasive predatory species have also been blamed for amphibian declines. Still other underlying factors may include infectious diseases caused by the chytrid fungus Batrachochytrium dendrobatidis, pathogenic viruses (Ranavirus), and other agents. It is nearly certain that more than one etiology is to blame for the majority of the global amphibian declines, and that these causal factors include some combination of climatological or physical habitat destabilization and infectious disease, most notably chytridiomycosis. Scientific research efforts are aimed at elucidating these etiologies on local, regional, and global scales that we might better understand and counteract the driving forces behind amphibian declines. Conservation efforts as outlined in the Amphibian Conservation Action Plan of 2005 are also being made to curtail losses and prevent further extinctions wherever possible.

  5. Tropical amphibian populations experience higher disease risk in natural habitats.

    Science.gov (United States)

    Becker, C Guilherme; Zamudio, Kelly R

    2011-06-14

    Habitat loss and disease are main drivers of global amphibian declines, yet the interaction between them remains largely unexplored. Here we show that paradoxically, habitat loss is negatively associated with occurrence, prevalence, and infection intensity of the chytrid fungus Batrachochytrium dendrobatidis (Bd) in amphibian populations in the tropics. At a large spatial scale, increased habitat loss predicted lower disease risk in amphibian populations across Costa Rica and eastern Australia, even after jointly considering the effect of potential biotic and abiotic correlates. Lower host-species richness and suboptimal microclimates for Bd in disturbed habitats are potential mechanisms underlying this pattern. Furthermore, we found that anthropogenic deforestation practices biased to lowlands and natural vegetation remaining in inaccessible highlands explain increased Bd occurrence at higher elevations. At a smaller spatial scale, holding constant elevation, latitude, and macroclimate, we also found a negative relationship between habitat loss, and both Bd prevalence and infection intensity in frog populations in two landscapes of the Brazilian Atlantic Forest. Our results indicate that amphibians will be disproportionately affected by emerging diseases in pristine environments, and that, paradoxically, disturbed habitats may act as shelters from disease, but only for the very few species that can tolerate deforestation. Thus, tropical amphibian faunas are threatened both by destruction of natural habitats as well as increased disease in pristine forests. To curb further extinctions and develop effective mitigation and restoration programs we must look to interactions between habitat loss and disease, the two main factors at the root of global amphibian declines.

  6. Evolution of the amygdala: new insights from studies in amphibians.

    Science.gov (United States)

    Laberge, Frédéric; Mühlenbrock-Lenter, Sabine; Grunwald, Wolfgang; Roth, Gerhard

    2006-01-01

    The histology of amphibian brains gives an impression of relative simplicity when compared with that of reptiles or mammals. The amphibian telencephalon is small and contains comparatively few and large neurons, which in most parts constitute a dense periventricular cellular layer. However, the view emerging from the last decade is that the brains of all tetrapods, including amphibians, share a general bauplan resulting from common ancestry and the need to perform similar vital functions. To what extent this common organization also applies to higher brain functions is unknown due to a limited knowledge of the neurobiology of early vertebrates. The amygdala is widely recognized as a brain center critical for basic forms of emotional learning (e.g., fear conditioning) and its structure in amphibians could suggest how this capacity evolved. A functional systems approach is used here to synthesize the results of our anatomical investigations of the amphibian amygdala. It is proposed that the connectivity of the amphibian telencephalon portends a capacity for multi-modal association in a limbic system largely similar to that of amniote vertebrates. One remarkable exception is the presence of new sensory-associative regions of the amygdala in amniotes: the posterior dorsal ventricular ridge plus lateral nuclei in reptiles and the basolateral complex in mammals. These presumably homologous regions apparently are capable of modulating the phylogenetically older central amygdala and allow more complex forms of emotional learning.

  7. Why amphibians are more sensitive than mammals to xenobiotics.

    Science.gov (United States)

    Quaranta, Angelo; Bellantuono, Vito; Cassano, Giuseppe; Lippe, Claudio

    2009-11-04

    Dramatic declines in amphibian populations have been described all over the world since the 1980s. The evidence that the sensitivity to environmental threats is greater in amphibians than in mammals has been generally linked to the observation that amphibians are characterized by a rather permeable skin. Nevertheless, a numerical comparison of data of percutaneous (through the skin) passage between amphibians and mammals is lacking. Therefore, in this investigation we have measured the percutaneous passage of two test molecules (mannitol and antipyrine) and three heavily used herbicides (atrazine, paraquat and glyphosate) in the skin of the frog Rana esculenta (amphibians) and of the pig ear (mammals), by using the same experimental protocol and a simple apparatus which minimizes the edge effect, occurring when the tissue is clamped in the usually used experimental device.The percutaneous passage (P) of each substance is much greater in frog than in pig. LogP is linearly related to logKow (logarithm of the octanol-water partition coefficient). The measured P value of atrazine was about 134 times larger than that of glyphosate in frog skin, but only 12 times in pig ear skin. The FoD value (Pfrog/Ppig) was 302 for atrazine, 120 for antipyrine, 66 for mannitol, 29 for paraquat, and 26 for glyphosate.The differences in structure and composition of the skin between amphibians and mammals are discussed.

  8. Predation of Ladybird Beetles (Coleoptera: Coccinellidae by Amphibians

    Directory of Open Access Journals (Sweden)

    John J. Sloggett

    2012-07-01

    Full Text Available Studies of predation of ladybird beetles (Coccinellidae have focused on a limited number of predator taxa, such as birds and ants, while other potential predators have received limited attention. I here consider amphibians as predators of ladybirds. Published amphibian gut analyses show that ladybirds are quite often eaten by frogs and toads (Anura, with recorded frequencies reaching up to 15% of dietary items. Salamanders (Caudata eat ladybirds less frequently, probably as their habits less often bring them into contact with the beetles. Amphibians do not appear to be deleteriously affected by the potentially toxic alkaloids that ladybirds possess. Amphibians, especially frogs and toads, use primarily prey movement as a release cue to attack their food; it is thus likely that their ability to discriminate against ladybirds and other chemically defended prey is limited. Because of this poor discriminatory power, amphibians have apparently evolved non-specific resistance to prey defensive chemicals, including ladybird alkaloids. Although amphibian-related ladybird mortality is limited, in certain habitats it could outweigh mortality from more frequently studied predators, notably birds. The gut analyses from the herpetological literature used in this study, suggest that in studying predation of insects, entomologists should consider specialized literature on other animal groups.

  9. Baseline Population Inventory of Amphibians on the Mountain Longleaf National Wildlife Refuge and Screening for the Amphibian Disease Batrachochytrium dendrobatidis

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — From July of 2012 to June of 2013, we conducted baseline inventories for amphibians and sampled for the disease Batrachochytrium dendrobatidis on the Mountain...

  10. Hormone-like peptides in the venoms of marine cone snails

    DEFF Research Database (Denmark)

    Robinson, Samuel D.; Li, Qing; Bandyopadhyay, Pradip K.

    2017-01-01

    The venoms of cone snails (genus Conus) are remarkably complex, consisting of hundreds of typically short, disulfide-rich peptides termed conotoxins. These peptides have diverse pharmacological targets, with injection of venom eliciting a range of physiological responses, including sedation...... in the venoms of cone snails we systematically mined the venom gland transcriptomes of several cone snail species and examined secreted venom peptides in dissected and injected venom of the Australian cone snail Conus victoriae. Using this approach we identified several novel hormone/neuropeptide-like toxins...

  11. Component Analysis of Bee Venom from lune to September

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    Ki Rok Kwon

    2007-06-01

    Full Text Available Objectives : The aim of this study was to observe variation of Bee Venom content from the collection period. Methods : Content analysis of Bee Venom was rendered using HPLC method by standard melittin Results : Analyzing melittin content using HPLC, 478.97mg/g at june , 493.89mg/g at july, 468.18mg/g at August and 482.15mg/g was containing in Bee Venom at september. So the change of melittin contents was no significance from June to September. Conclusion : Above these results, we concluded carefully that collecting time was not important factor for the quality control of Bee Venom, restricted the period from June to September.

  12. Biotechnological applications of brown spider (Loxosceles genus) venom toxins.

    Science.gov (United States)

    Senff-Ribeiro, Andrea; Henrique da Silva, Paulo; Chaim, Olga Meiri; Gremski, Luiza Helena; Paludo, Kátia Sabrina; Bertoni da Silveira, Rafael; Gremski, Waldemiro; Mangili, Oldemir Carlos; Veiga, Silvio Sanches

    2008-01-01

    Loxoscelism (the term used to define accidents by the bite of brown spiders) has been reported worldwide. Clinical manifestations following brown spider bites are frequently associated with skin degeneration, a massive inflammatory response at the injured region, intravascular hemolysis, platelet aggregation causing thrombocytopenia and renal disturbances. The mechanisms by which the venom exerts its noxious effects are currently under investigation. The whole venom is a complex mixture of toxins enriched with low molecular mass proteins in the range of 5-40 kDa. Toxins including alkaline phosphatase, hyaluronidase, metalloproteases (astacin-like proteases), low molecular mass (5.6-7.9 kDa) insecticidal peptides and phospholipases-D (dermonecrotic toxins) have been identified in the venom. The purpose of the present review is to describe biotechnological applications of whole venom or some toxins, with especial emphasis upon molecular biology findings obtained in the last years.

  13. Applications of snake venoms in treatment of cancer

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    Vagish Kumar Laxman Shanbhag

    2015-04-01

    Full Text Available Snake venoms are folk medicines used since ages. The components of snake venoms have high specific affinity and actions on cells and cell components. Also snake venoms are largely cytotoxic to tumor cells than normal cells. In addition to these, they have several therapeutic actions that make them an attractive option in the management of cancer. The advent of modern technologies has greatly helped in extracting and identifying new components of therapeutic interests in short time. The article highlights the importance of snake venoms in the management of cancer, so as to motivate curious researchers to devote their skills in this fascinating area. This in turn may bring hope, smile and relief to several cancer patients in future.

  14. Applications of snake venoms in treatment of cancer

    Institute of Scientific and Technical Information of China (English)

    Vagish; Kumar; Laxman; Shanbhag

    2015-01-01

    Snake venoms are folk medicines used since ages. The components of snake venoms have high specific affinity and actions on cells and cell components. Also snake venoms are largely cytotoxic to tumor cells than normal cells. In addition to these, they have several therapeutic actions that make them an attractive option in the management of cancer. The advent of modern technologies has greatly helped in extracting and identifying new components of therapeutic interests in short time. The article highlights the importance of snake venoms in the management of cancer, so as to motivate curious researchers to devote their skills in this fascinating area. This in turn may bring hope, smile and relief to several cancer patients in future.

  15. Neurobiology: venom of wasps and initiation of movements.

    Science.gov (United States)

    Zill, Sasha N; Keller, Bridget R

    2008-06-24

    The ability to initiate movements can be impaired in some brain injuries even though motor actions proceed normally once they are begun. The effects of venom that wasps use in preying upon cockroaches could provide insights into this problem.

  16. Effects of Sweet Bee Venom and Bee Venom on the Heart Rate Variability

    Directory of Open Access Journals (Sweden)

    Yook Tae-Han

    2008-03-01

    Full Text Available Objective : In this study, we investigated the effects of Sweet Bee Venom(SBV and Bee Venom(BV at a acupoint, HT7(Shinmun on the Heart Rate Variability(HRV in the healthy man. And we tried to observe how Sweet Bee Venom and Bee Venom affects on the balance of the autonomic nervous system. Methods : We investigated on 22 heathy volunteers consisted of 10 subjects in SBV group and 12 subjects in BV group. Study form was a randomized, placebo-controlled, double-blind clinical trial. 22 subjects of each group were injected SBV and BV at HT7(Shinmun. And we measured HRV by QECG-3:LXC3203 (LAXTHA Inc. Korea on 7 times : before and after injection per 5minutes during 30minutes. Results : 1. After SBV injection, Mean-RR was significantly high from 0 to 10 minutes, Mean-HRV was significantly low from 0 to 10 minutes, SDNN was significantly high after 25minutes, Complexity was significantly high from 5 to 10minutes and RMSSD was significantly high from 5 to 10minutes. 2. Complexity of SBV Group significantly decreased from 20 to 25minutes, RMSSD of SBV Group significantly increased from 10 to 15minute and from 20~25minutes, SDSD of SBV Group significantly increased from 10 to 15 minute and from 20~25minutes compared with that of BV group. 3. After SBV injection, Ln(VLF was significantly from 25 to 30minutes. Conclusions : The results suggest that SBV in heathy adult man tend to activate the autonomic nervous system compared to BV within normal range.

  17. Peptidomic and transcriptomic profiling of four distinct spider venoms

    Science.gov (United States)

    Oldrati, Vera; Koua, Dominique; Allard, Pierre-Marie; Hulo, Nicolas; Arrell, Miriam; Nentwig, Wolfgang; Lisacek, Frédérique; Wolfender, Jean-Luc; Kuhn-Nentwig, Lucia; Stöcklin, Reto

    2017-01-01

    Venom based research is exploited to find novel candidates for the development of innovative pharmacological tools, drug candidates and new ingredients for cosmetic and agrochemical industries. Moreover, venomics, as a well-established approach in systems biology, helps to elucidate the genetic mechanisms of the production of such a great molecular biodiversity. Today the advances made in the proteomics, transcriptomics and bioinformatics fields, favor venomics, allowing the in depth study of complex matrices and the elucidation even of minor compounds present in minute biological samples. The present study illustrates a rapid and efficient method developed for the elucidation of venom composition based on NextGen mRNA sequencing of venom glands and LC-MS/MS venom proteome profiling. The analysis of the comprehensive data obtained was focused on cysteine rich peptide toxins from four spider species originating from phylogenetically distant families for comparison purposes. The studied species were Heteropoda davidbowie (Sparassidae), Poecilotheria formosa (Theraphosidae), Viridasius fasciatus (Viridasiidae) and Latrodectus mactans (Theridiidae). This led to a high resolution profiling of 284 characterized cysteine rich peptides, 111 of which belong to the Inhibitor Cysteine Knot (ICK) structural motif. The analysis of H. davidbowie venom revealed a high richness in term of venom diversity: 95 peptide sequences were identified; out of these, 32 peptides presented the ICK structural motif and could be classified in six distinct families. The profiling of P. formosa venom highlighted the presence of 126 peptide sequences, with 52 ICK toxins belonging to three structural distinct families. V. fasciatus venom was shown to contain 49 peptide sequences, out of which 22 presented the ICK structural motif and were attributed to five families. The venom of L. mactans, until now studied for its large neurotoxins (Latrotoxins), revealed the presence of 14 cysteine rich

  18. Multiple stressor effects in relation to declining amphibian populations

    Science.gov (United States)

    2003-01-01

    This book represents the work of several authors who participated in the symposium entitled 'Multiple Stressor Effects in Relation to Declining Amphibian Populations' convened 16-17 April, 2002, in Pittsburgh, Pennsylvania. Declines of amphibian populations of varying severity have been observed for many years, and in the last 8 to 10 years considerable progress has been made in documenting the status and distribution of a range of amphibian species. Habitat alteration and destruction are likely linked to many amphibian declines, but a variety of other factors, both anthropogenic and natural, have been observed or proposed to have caused declines or extinctions of amphibian populations. Unfortunately, determining the environmental causes for the decline of many species has proven difficult. The goals of this symposium were three-fold. First, highlight ASTM's historic role in providing a forum for the standardization of amphibian toxicity test methods and the characterization of adverse effects potentially associated with chemical stressors. Second, demonstrate through case studies the current state of technical 'tools' available to biologists, ecologists, environmental scientists and natural resource professionals for assessing amphibian populations exposed to various environmental stressors. And third, characterize a process that brings a range of interdisciplinary technical and management tools to the tasks of causal analysis, especially as those relate to a multiple stressor risk assessment 'mind-set.' As part of the symposium, scientists and resource management professionals from diverse fields including ecotoxicology and chemistry, ecology and field biology, conservation biology, and natural resource management and policy contributed oral presentations and posters that addressed topics related to declining amphibian populations and the role that various stressors have in those losses. The papers contained in this publication reflect the commitment of ASTM

  19. [Technogenic factors of ecological impact on properties of snake venom].

    Science.gov (United States)

    Abiev, G A; Babaev, E T; Topchieva, Sh A; Chuburidze, T B; Kikalishvili, B Iu

    2009-12-01

    In article comparative literary and experimental data about degree of a level of scrutiny of snake venoms are presented. Obtained data shows that increased pollution of industrial regions results in higher levels of heavy metals in snake venom. Change of physical and chemical parametres, and also pharmacological activity and toxicity of zootoxins under influence biotics, abiotics factors and including heavy metals and radiation is noted.

  20. Venom Proteome of the Box Jellyfish Chironex fleckeri

    OpenAIRE

    2012-01-01

    The nematocyst is a complex intracellular structure unique to Cnidaria. When triggered to discharge, the nematocyst explosively releases a long spiny, tubule that delivers an often highly venomous mixture of components. The box jellyfish, Chironex fleckeri, produces exceptionally potent and rapid-acting venom and its stings to humans cause severe localized and systemic effects that are potentially life-threatening. In an effort to identify toxins that could be responsible for the serious heal...

  1. Triacontyl p-coumarate: an inhibitor of snake venom metalloproteinases.

    Science.gov (United States)

    Mendes, M M; Vieira, S A P B; Gomes, M S R; Paula, V F; Alcântara, T M; Homsi-Brandeburgo, M I; dos Santos, J I; Magro, A J; Fontes, M R M; Rodrigues, V M

    2013-02-01

    Snake venom metalloproteinases (SVMPs) participate in a number of important biological, physiological and pathophysiological processes and are primarily responsible for the local tissue damage characteristic of viperid snake envenomations. The use of medicinal plant extracts as antidotes against animal venoms is an old practice, especially against snake envenomations. Such plants are sources of many pharmacologically active compounds and have been shown to antagonize the effects of some venoms and toxins. The present study explores the activity of triacontyl p-coumarate (PCT), an active compound isolated from root bark of Bombacopsis glabra vegetal extract (Bg), against harmful effects of Bothropoides pauloensis snake venom and isolated toxins (SVMPs or phospholipase A(2)). Before inhibition assays, Bg or PCT was incubated with venom or toxins at ratios of 1:1 and 1:5 (w/w; venom or isolated toxins/PCT) for 30 min at 37°C. Treatment conditions were also assayed to simulate snakebite with PCT inoculated at either the same venom or toxin site. PCT neutralized fibrinogenolytic activity and plasmatic fibrinogen depletion induced by B. pauloensis venom or isolated toxin. PCT also efficiently inhibited the hemorrhagic (3MDH - minimum hemorrhagic dose injected i.d into mice) and myotoxic activities induced by Jararhagin, a metalloproteinase from B. jararaca at 1:5 ratio (toxin: inhibitor, w/w) when it was previously incubated with PCT and injected into mice or when PCT was administered after toxin injection. Docking simulations using data on a metalloproteinase (Neuwiedase) structure suggest that the binding between the protein and the inhibitor occurs mainly in the active site region causing blockade of the enzymatic reaction by displacement of catalytic water. Steric hindrance may also play a role in the mechanism since the PCT hydrophobic tail was found to interact with the loop associated with substrate anchorage. Thus, PCT may provide a alternative to complement

  2. IN VIVO NEUTRALIZATION OF NAJA NIGRICOLLIS VENOM BY UVARIA CHAMAE

    Directory of Open Access Journals (Sweden)

    Omale James

    2013-01-01

    Full Text Available Uvaria chamae is a well known medicinal plant in Nigerian traditional medicine for the management of many diseases, but investigations concerning its pharmacological characteristics are rare. In this study, we evaluate its venom neutralizing properties against Naja nigricollis venom in rats. Freshly collected Uvaria chamae leaves were air dried, powdered and extracted in methanol. To study the antivenom properties, albino rats were orally administered with a dose of 400 mg kg-1 body weight and one hour later, the venom was administered intraperitoneally at a dose of 0.08 mg kg-1 body weight of rats. Albino rats (male weighing between 180-200g were randomly divided into five (5 groups of three (3. Groups 1-5 received water, normal saline, venom, Uvaria chamae and venom, Uvaria chamae respectively. Blood clothing time, bleeding time, antipyretic activity, haemoglobin, RBC, WBC, creatine kinase, AST, ALP and ALT activities total protein antioxidant activity and some blood electrolytes, plasma urea and uric acid were measured. Our results showed that Uvaria chamae methanol extract neutralized some biological effects of Naja nigricollis venom. The venom increased the rectal temperature, enzyme activities, bleeding time and other blood parameters. The plant extract was able to reduce these parameters in the extract treated groups. Details of the results are discussed. From this study, it is clear that U. chamae leaf extract had antivenom activity in animal models. The above results indicate that the plant extract possess potent snake venom neutralizing capacity and could potentially be used for therapeutic purpose in case of snake bite envenomation.

  3. Molecular Diversity and Gene Evolution of the Venom Arsenal of Terebridae Predatory Marine Snails.

    Science.gov (United States)

    Gorson, Juliette; Ramrattan, Girish; Verdes, Aida; Wright, Elizabeth M; Kantor, Yuri; Rajaram Srinivasan, Ramakrishnan; Musunuri, Raj; Packer, Daniel; Albano, Gabriel; Qiu, Wei-Gang; Holford, Mandë

    2015-05-28

    Venom peptides from predatory organisms are a resource for investigating evolutionary processes such as adaptive radiation or diversification, and exemplify promising targets for biomedical drug development. Terebridae are an understudied lineage of conoidean snails, which also includes cone snails and turrids. Characterization of cone snail venom peptides, conotoxins, has revealed a cocktail of bioactive compounds used to investigate physiological cellular function, predator-prey interactions, and to develop novel therapeutics. However, venom diversity of other conoidean snails remains poorly understood. The present research applies a venomics approach to characterize novel terebrid venom peptides, teretoxins, from the venom gland transcriptomes of Triplostephanus anilis and Terebra subulata. Next-generation sequencing and de novo assembly identified 139 putative teretoxins that were analyzed for the presence of canonical peptide features as identified in conotoxins. To meet the challenges of de novo assembly, multiple approaches for cross validation of findings were performed to achieve reliable assemblies of venom duct transcriptomes and to obtain a robust portrait of Terebridae venom. Phylogenetic methodology was used to identify 14 teretoxin gene superfamilies for the first time, 13 of which are unique to the Terebridae. Additionally, basic local algorithm search tool homology-based searches to venom-related genes and posttranslational modification enzymes identified a convergence of certain venom proteins, such as actinoporin, commonly found in venoms. This research provides novel insights into venom evolution and recruitment in Conoidean predatory marine snails and identifies a plethora of terebrid venom peptides that can be used to investigate fundamental questions pertaining to gene evolution.

  4. Venomic Analysis of the Poorly Studied Desert Coral Snake, Micrurus tschudii tschudii, Supports the 3FTx/PLA2 Dichotomy across Micrurus Venoms

    Directory of Open Access Journals (Sweden)

    Libia Sanz

    2016-06-01

    Full Text Available The venom proteome of the poorly studied desert coral snake Micrurus tschudii tschudii was unveiled using a venomic approach, which identified ≥38 proteins belonging to only four snake venom protein families. The three-finger toxins (3FTxs constitute, both in number of isoforms (~30 and total abundance (93.6% of the venom proteome, the major protein family of the desert coral snake venom. Phospholipases A2 (PLA2s; seven isoforms, 4.1% of the venom proteome, 1–3 Kunitz-type proteins (1.6%, and 1–2 l-amino acid oxidases (LAO, 0.7% complete the toxin arsenal of M. t. tschudii. Our results add to the growing evidence that the occurrence of two divergent venom phenotypes, i.e., 3FTx- and PLA2-predominant venom proteomes, may constitute a general trend across the cladogenesis of Micrurus. The occurrence of a similar pattern of venom phenotypic variability among true sea snake (Hydrophiinae venoms suggests that the 3FTx/PLA2 dichotomy may be widely distributed among Elapidae venoms.

  5. Venomic Analysis of the Poorly Studied Desert Coral Snake, Micrurus tschudii tschudii, Supports the 3FTx/PLA₂ Dichotomy across Micrurus Venoms.

    Science.gov (United States)

    Sanz, Libia; Pla, Davinia; Pérez, Alicia; Rodríguez, Yania; Zavaleta, Alfonso; Salas, Maria; Lomonte, Bruno; Calvete, Juan J

    2016-06-07

    The venom proteome of the poorly studied desert coral snake Micrurus tschudii tschudii was unveiled using a venomic approach, which identified ≥38 proteins belonging to only four snake venom protein families. The three-finger toxins (3FTxs) constitute, both in number of isoforms (~30) and total abundance (93.6% of the venom proteome), the major protein family of the desert coral snake venom. Phospholipases A₂ (PLA₂s; seven isoforms, 4.1% of the venom proteome), 1-3 Kunitz-type proteins (1.6%), and 1-2 l-amino acid oxidases (LAO, 0.7%) complete the toxin arsenal of M. t. tschudii. Our results add to the growing evidence that the occurrence of two divergent venom phenotypes, i.e., 3FTx- and PLA₂-predominant venom proteomes, may constitute a general trend across the cladogenesis of Micrurus. The occurrence of a similar pattern of venom phenotypic variability among true sea snake (Hydrophiinae) venoms suggests that the 3FTx/PLA₂ dichotomy may be widely distributed among Elapidae venoms.

  6. Venomic Analysis of the Poorly Studied Desert Coral Snake, Micrurus tschudii tschudii, Supports the 3FTx/PLA2 Dichotomy across Micrurus Venoms

    Science.gov (United States)

    Sanz, Libia; Pla, Davinia; Pérez, Alicia; Rodríguez, Yania; Zavaleta, Alfonso; Salas, Maria; Lomonte, Bruno; Calvete, Juan J.

    2016-01-01

    The venom proteome of the poorly studied desert coral snake Micrurus tschudii tschudii was unveiled using a venomic approach, which identified ≥38 proteins belonging to only four snake venom protein families. The three-finger toxins (3FTxs) constitute, both in number of isoforms (~30) and total abundance (93.6% of the venom proteome), the major protein family of the desert coral snake venom. Phospholipases A2 (PLA2s; seven isoforms, 4.1% of the venom proteome), 1–3 Kunitz-type proteins (1.6%), and 1–2 l-amino acid oxidases (LAO, 0.7%) complete the toxin arsenal of M. t. tschudii. Our results add to the growing evidence that the occurrence of two divergent venom phenotypes, i.e., 3FTx- and PLA2-predominant venom proteomes, may constitute a general trend across the cladogenesis of Micrurus. The occurrence of a similar pattern of venom phenotypic variability among true sea snake (Hydrophiinae) venoms suggests that the 3FTx/PLA2 dichotomy may be widely distributed among Elapidae venoms. PMID:27338473

  7. Venom proteome of the box jellyfish Chironex fleckeri.

    Directory of Open Access Journals (Sweden)

    Diane L Brinkman

    Full Text Available The nematocyst is a complex intracellular structure unique to Cnidaria. When triggered to discharge, the nematocyst explosively releases a long spiny, tubule that delivers an often highly venomous mixture of components. The box jellyfish, Chironex fleckeri, produces exceptionally potent and rapid-acting venom and its stings to humans cause severe localized and systemic effects that are potentially life-threatening. In an effort to identify toxins that could be responsible for the serious health effects caused by C. fleckeri and related species, we used a proteomic approach to profile the protein components of C. fleckeri venom. Collectively, 61 proteins were identified, including toxins and proteins important for nematocyte development and nematocyst formation (nematogenesis. The most abundant toxins identified were isoforms of a taxonomically restricted family of potent cnidarian proteins. These toxins are associated with cytolytic, nociceptive, inflammatory, dermonecrotic and lethal properties and expansion of this important protein family goes some way to explaining the destructive and potentially fatal effects of C. fleckeri venom. Venom proteins and their post-translational modifications (PTMs were further characterized using toxin-specific antibodies and phosphoprotein/glycoprotein-specific stains. Results indicated that glycosylation is a common PTM of the toxin family while a lack of cross-reactivity by toxin-specific antibodies infers there is significant divergence in structure and possibly function among family members. This study provides insight into the depth and diversity of protein toxins produced by harmful box jellyfish and represents the first description of a cubozoan jellyfish venom proteome.

  8. Venom proteome of the box jellyfish Chironex fleckeri.

    Science.gov (United States)

    Brinkman, Diane L; Aziz, Ammar; Loukas, Alex; Potriquet, Jeremy; Seymour, Jamie; Mulvenna, Jason

    2012-01-01

    The nematocyst is a complex intracellular structure unique to Cnidaria. When triggered to discharge, the nematocyst explosively releases a long spiny, tubule that delivers an often highly venomous mixture of components. The box jellyfish, Chironex fleckeri, produces exceptionally potent and rapid-acting venom and its stings to humans cause severe localized and systemic effects that are potentially life-threatening. In an effort to identify toxins that could be responsible for the serious health effects caused by C. fleckeri and related species, we used a proteomic approach to profile the protein components of C. fleckeri venom. Collectively, 61 proteins were identified, including toxins and proteins important for nematocyte development and nematocyst formation (nematogenesis). The most abundant toxins identified were isoforms of a taxonomically restricted family of potent cnidarian proteins. These toxins are associated with cytolytic, nociceptive, inflammatory, dermonecrotic and lethal properties and expansion of this important protein family goes some way to explaining the destructive and potentially fatal effects of C. fleckeri venom. Venom proteins and their post-translational modifications (PTMs) were further characterized using toxin-specific antibodies and phosphoprotein/glycoprotein-specific stains. Results indicated that glycosylation is a common PTM of the toxin family while a lack of cross-reactivity by toxin-specific antibodies infers there is significant divergence in structure and possibly function among family members. This study provides insight into the depth and diversity of protein toxins produced by harmful box jellyfish and represents the first description of a cubozoan jellyfish venom proteome.

  9. Screening for fibrinolytic activity in eight Viperid venoms.

    Science.gov (United States)

    Ramírez, M S; Sánchez, E E; García-Prieto, C; Pérez, J C; Chapa, G R; McKeller, M R; Ramírez, R; De Anda, Y

    1999-09-01

    Snake venoms contain direct-acting fibrinolytic metalloproteinases (MMP) that could have important applications in medicine. Fibrinolytic enzymes isolated from venom can induce in vitro clot lysis by directly acting on a fibrin clot. The most ideal fibrinolytic enzyme would have high affinity for clots, dissolve clots directly without causing hemorrhage, and would not be neutralized in vivo by endogenous metalloproteinase inhibitors. The purpose of this study was to compare DEAE/HPLC venom profiles from Viperid snakes and identify fractions that contain fibrinolytic activity with no hemorrhagic activity and are not neutralized by animal sera. The sera selected were from four (Virginia opossum, Gray woodrat, Mexican ground squirrel, and Hispid cottonrat) animals known to neutralize hemorrhagic activity in snake venoms. Nineteen fractions from the Viperid venoms had fibrinolytic activity. Agkistrodon venom fractions contained the highest specific fibrinolytic activities. A. piscivorus leucostoma fraction 4 contained a high specific fibrinolytic activity, no hemorrhagic activity, and the fibrinolytic activity was not neutralized by the proteinase inhibitors of the four animal sera. A. contortrix laticinctus fraction 1 also had a high specific fibrinolytic activity and no hemorrhagic activity. However, the fibrinolytic activity was neutralized by Didelphis virginiana (Virginia opossum) serum.

  10. Embryotoxicity following repetitive maternal exposure to scorpion venom

    Directory of Open Access Journals (Sweden)

    BN Hmed

    2012-01-01

    Full Text Available Although it is a frequent accident in a few countries, scorpion envenomation during pregnancy remains scarcely studied. In the present study, the effects of repetitive maternal exposure to Buthus occitanus tunetanus venom are investigated and its possible embryotoxic consequences on rats. Primigravid rats received a daily intraperitoneal dose of 1 mL/kg of saline solution or 300 µg/kg of crude scorpion venom, from the 7th to the 13th day of gestation. On the 21st day, the animals were deeply anesthetized using diethyl-ether. Then, blood was collected for chemical parameter analysis. Following euthanasia, morphometric measurements were carried out. The results showed a significant increase in maternal heart and lung absolute weights following venom treatment. However, the mean placental weight per rat was significantly diminished. Furthermore, blood urea concentration was higher in exposed rats (6.97 ± 0.62 mmol/L than in those receiving saline solution (4.94 ± 0.90 mmol/L. Many organs of venom-treated rat fetuses (brain, liver, kidney and spleen were smaller than those of controls. On the contrary, fetal lungs were significantly heavier in fetuses exposed to venom (3.2 ± 0.4 g than in the others (3.0 ± 0.2 g. Subcutaneous blood clots, microphthalmia and total body and tail shortening were also observed in venom-treated fetuses. It is concluded that scorpion envenomation during pregnancy potentially causes intrauterine fetal alterations and growth impairment.

  11. Unraveling the processing and activation of snake venom metalloproteinases.

    Science.gov (United States)

    Portes-Junior, José A; Yamanouye, Norma; Carneiro, Sylvia M; Knittel, Paloma S; Sant'Anna, Sávio S; Nogueira, Fabio C S; Junqueira, Magno; Magalhães, Geraldo S; Domont, Gilberto B; Moura-da-Silva, Ana M

    2014-07-03

    Snake venom metalloproteinases (SVMPs) are zinc-dependent enzymes responsible for most symptoms of human envenoming. Like matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinase (ADAM) proteins, SVMPs are synthesized as zymogens, and enzyme activation is regulated by hydrolysis of their prodomain, but the processing of SVMPs is still unclear. In this study, we attempted to identify the presence of prodomain in different compartments of snake venom glands as zymogens or in the free form to elucidate some mechanism involved in SVMP activation. Using antibodies obtained by immunization with a recombinant prodomain, bands of zymogen molecular mass and prodomain peptides were detected mostly in gland extracts all along the venom production cycle and in the venom collected from the lumen at the peak of venom production. Prodomain was detected in secretory cells mostly in the secretory vesicles near the Golgi. We hypothesize that the processing of SVMPs starts within secretory vesicles and continues in the lumen of the venom gland just after enzyme secretion and involves different steps compared to ADAMs and MMPs but can be used as a model for studying the relevance of peptides resulting from prodomain processing and degradation for controlling the activity of metalloproteinases.

  12. Extracellular matrix molecules as targets for brown spider venom toxins

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    Veiga S.S.

    2001-01-01

    Full Text Available Loxoscelism, the term used to describe lesions and clinical manifestations induced by brown spider's venom (Loxosceles genus, has attracted much attention over the last years. Brown spider bites have been reported to cause a local and acute inflammatory reaction that may evolve to dermonecrosis (a hallmark of envenomation and hemorrhage at the bite site, besides systemic manifestations such as thrombocytopenia, disseminated intravascular coagulation, hemolysis, and renal failure. The molecular mechanisms by which Loxosceles venoms induce injury are currently under investigation. In this review, we focused on the latest reports describing the biological and physiopathological aspects of loxoscelism, with reference mainly to the proteases recently described as metalloproteases and serine proteases, as well as on the proteolytic effects triggered by L. intermedia venom upon extracellular matrix constituents such as fibronectin, fibrinogen, entactin and heparan sulfate proteoglycan, besides the disruptive activity of the venom on Engelbreth-Holm-Swarm basement membranes. Degradation of these extracellular matrix molecules and the observed disruption of basement membranes could be related to deleterious activities of the venom such as loss of vessel and glomerular integrity and spreading of the venom toxins to underlying tissues.

  13. Developments in amphibian captive breeding and reintroduction programs.

    Science.gov (United States)

    Harding, Gemma; Griffiths, Richard A; Pavajeau, Lissette

    2016-04-01

    Captive breeding and reintroduction remain high profile but controversial conservation interventions. It is important to understand how such programs develop and respond to strategic conservation initiatives. We analyzed the contribution to conservation made by amphibian captive breeding and reintroduction since the launch of the International Union for Conservation of Nature (IUCN) Amphibian Conservation Action Plan (ACAP) in 2007. We assembled data on amphibian captive breeding and reintroduction from a variety of sources including the Amphibian Ark database and the IUCN Red List. We also carried out systematic searches of Web of Science, JSTOR, and Google Scholar for relevant literature. Relative to data collected from 1966 to 2006, the number of species involved in captive breeding and reintroduction projects increased by 57% in the 7 years since release of the ACAP. However, there have been relatively few new reintroductions over this period; most programs have focused on securing captive-assurance populations (i.e., species taken into captivity as a precaution against extinctions in the wild) and conservation-related research. There has been a shift to a broader representation of frogs, salamanders, and caecilians within programs and an increasing emphasis on threatened species. There has been a relative increase of species in programs from Central and South America and the Caribbean, where amphibian biodiversity is high. About half of the programs involve zoos and aquaria with a similar proportion represented in specialist facilities run by governmental or nongovernmental agencies. Despite successful reintroduction often being regarded as the ultimate milestone for such programs, the irreversibility of many current threats to amphibians may make this an impractical goal. Instead, research on captive assurance populations may be needed to develop imaginative solutions to enable amphibians to survive alongside current, emerging, and future threats.

  14. Translocations of amphibians: Proven management method or experimental technique

    Science.gov (United States)

    Seigel, Richard A.; Dodd, C. Kenneth

    2002-01-01

    In an otherwise excellent review of metapopulation dynamics in amphibians, Marsh and Trenham (2001) make the following provocative statements (emphasis added): If isolation effects occur primarily in highly disturbed habitats, species translocations may be necessary to promote local and regional population persistence. Because most amphibians lack parental care, they areprime candidates for egg and larval translocations. Indeed, translocations have already proven successful for several species of amphibians. Where populations are severely isolated, translocations into extinct subpopulations may be the best strategy to promote regional population persistence. We take issue with these statements for a number of reasons. First, the authors fail to cite much of the relevant literature on species translocations in general and for amphibians in particular. Second, to those unfamiliar with current research in amphibian conservation biology, these comments might suggest that translocations are a proven management method. This is not the case, at least in most instances where translocations have been evaluated for an appropriate period of time. Finally, the authors fail to point out some of the negative aspects of species translocation as a management method. We realize that Marsh and Trenham's paper was not concerned primarily with translocations. However, because Marsh and Trenham (2001) made specific recommendations for conservation planners and managers (many of whom are not herpetologists or may not be familiar with the pertinent literature on amphibians), we believe that it is essential to point out that not all amphibian biologists are as comfortable with translocations as these authors appear to be. We especially urge caution about advocating potentially unproven techniques without a thorough review of available options.

  15. Alexander Mikhailovich Zakharov and his works on the venom apparatus and venoms of some poisonous snakes

    Directory of Open Access Journals (Sweden)

    Cherlin Vladimir Alexandrovich

    2013-10-01

    Full Text Available The article gives brief biographical information about a very talented herpetologist Alexander M. Zakharov, and describes the general results of his works on the structure and function of venom glands of some poisonous snakes and their venoms. In his studies, he got the results, which are fundamentally different from the conventional concept of 30s - 70s of the XX century. Unfortunately, among physicians this concept has not changed up today. At that time it was thought that the poisons of Viperidae snakes are almost completely hemotoxic, and poisons of Elapidae (cobra are almost neurotoxic. But A.M.Zaharov found out, that poisons of both types of snakes (Viperidae and Elapidae include three groups of substances: hemotoxins, neurotoxins and non-toxic component – hyaluronidase. Each of these groups of substances is produced by independent part of venom glands and has its own special effect. Neurotoxins act on the central nervous system (mainly the respiratory center, but are greatly destroyed by means of the blood antigen properties and cannot pass through the hematoencephalic barrier. Hyaluronidase , connecting with neurotoxins, has an important property – to "smuggle" neurotoxins through the hematoencephalic barrier exactly into the target organ – the respiratory center in the central nervous system. In this case, neurotoxin enters the respiratory center not through the blood and lymph vessels, but directly through the nerve channel, through synapsis. The main function of hemotoxins is not to kill the victim, but to protect neurotoxins and hyaluronidase from the destructive activity of the victim's blood. Therefore, the target of the poisons of Viperidae and Elapidae snakes is the central nervous system of victims, but Elapidae has almost no hemotoxins. That’s why their striking effect can be achieved only by a strong increase in the amount of neurotoxins and hyaluronidase. Hemotoxins of Viperidae venoms permits to reduce the amount of

  16. Ion transport by the amphibian primary ureter

    DEFF Research Database (Denmark)

    Møbjerg, Nadja

    2008-01-01

    and it is furthermore a key player in the induction of these kidney generations. Whether the ureter participates in urine modification, remains to be elucidated. In amphibians the pronephros is a large organ, which is functional for a considerable time before it degenerates. The aim of this study was to investigate...... (Vm) was - 79 ± 11 mV (mean ± sd). Vm depolarized by 35 ± 8 mV (n = 21) upon a bath [K+] step from 3 to 20 mmol/l, demonstrating the presence of a large K+ conductance in the basolateral cell membrane. Luminal fluid exchange experiments in 4 cells revealed a depolarization of Vm in response to [K......+] steps from 3 to 20 mmol/l and a hyperpolarization of Vm upon lowering [Na+] from 102 to 2 mmol/l, indicating the presence of luminal K+ and Na+ conductances. This study provides the first functional data on the vertebrate primary ureter. The data show that the primary ureter of axolotl larvae...

  17. Neotropical Amphibian Declines Affect Stream Ecosystem Properties

    Science.gov (United States)

    Connelly, S.; Pringle, C. M.; Bixby, R. J.; Whiles, M. R.; Lips, K. R.; Brenes, R.; Colon-Gaud, J. C.; Kilham, S.; Hunte-Brown, M.

    2005-05-01

    Global declines of amphibians are well documented, yet effects of these dramatic losses on ecosystem structure and function are poorly understood. As part of a larger collaborative project, we compared two upland Panamanian streams. Both streams are biologically and geologically similar; however, one stream (Fortuna) has recently experienced almost complete extirpation of stream-dwelling frogs, while the other (Cope) still has intact populations. We experimentally excluded tadpoles from localized areas in each stream. We then compared chlorophyll a, algal community composition, ash-free dry mass (AFDM), inorganic matter, and insect assemblages in control and exclusion areas. Additionally, we sampled the natural substrate of both streams monthly for chlorophyll a, algal community composition, AFDM, and inorganic matter. At Cope, chlorophyll a, AFDM, and inorganic matter were greater in areas where tadpoles were excluded than in their presence. Numbers of dominant algal species (e.g., Nupela praecipua and Eunotia siolii) were greater in the exclusion versus control treatments. Monthly sampling of natural substrate indicated higher chlorophyll a and AFDM at Cope compared to Fortuna. Our data suggest that stream-dwelling anuran larvae have significant impacts on algal communities. These results also have implications for predicting the relevance of short-term experimental manipulations to long-term, whole-stream processes.

  18. Incentive or habit learning in amphibians?

    Directory of Open Access Journals (Sweden)

    Rubén N Muzio

    Full Text Available Toads (Rhinella arenarum received training with a novel incentive procedure involving access to solutions of different NaCl concentrations. In Experiment 1, instrumental behavior and weight variation data confirmed that such solutions yield incentive values ranging from appetitive (deionized water, DW, leading to weight gain, to neutral (300 mM slightly hypertonic solution, leading to no net weight gain or loss, and aversive (800 mM highly hypertonic solution leading to weight loss. In Experiment 2, a downshift from DW to a 300 mM solution or an upshift from a 300 mM solution to DW led to a gradual adjustment in instrumental behavior. In Experiment 3, extinction was similar after acquisition with access to only DW or with a random mixture of DW and 300 mM. In Experiment 4, a downshift from DW to 225, 212, or 200 mM solutions led again to gradual adjustments. These findings add to a growing body of comparative evidence suggesting that amphibians adjust to incentive shifts on the basis of habit formation and reorganization.

  19. Biochemical and pharmacological study of venom of the wolf spider Lycosa singoriensis

    Directory of Open Access Journals (Sweden)

    ZH Liu

    2009-01-01

    Full Text Available The wolf spider Lycosa singoriensis is a large and venomous spider distributed throughout northwestern China. Like other spider venoms, the wolf spider venom is a chemical cocktail. Its protein content is 0.659 mg protein/mg crude venom as determined by the Lowry method. MALDI-TOF analysis revealed that the venom peptides are highly diverse and may be divided into three groups characterized by three independent molecular ranges: 2,000 to 2,500 Da, 4,800 to 5,500 Da and 7,000 to 8,000 Da, respectively. This molecular distribution differs substantially from those of most spider venoms studied so far. This wolf spider venom has low neurotoxic action on mice, but it can induce hemolysis of human erythrocytes. Furthermore, the venom shows antimicrobial activity against prokaryotic and eukaryotic cells.

  20. Anti-venom potential of aqueous extract of stem bark of Mangifera indica L. against Daboia russellii (Russell's viper) venom.

    Science.gov (United States)

    Dhananjaya, B L; Zameer, F; Girish, K S; D'Souza, Cletus J M

    2011-06-01

    Several plant extracts rich in pharmacologically active compounds have shown to antagonize venom of several species. Mangifera indica has been used against snakebite by the traditional healers. However, there is paucity of scientific data in support. In this study, we evaluated the antivenom potential of aqueous extract of stem bark of M. indica against D. russellii venom-induced pharmacological effects such as life myotoxicity, edema, LD50 etc. The extract inhibited the phospholipase, protease, hyaluronidase, 5'nucleotidase, ATPase and alkaline phosphomonoesterase activities with varying IC50 values. It significantly inhibited both metalloproteases and serine proteases activities. Further, the extract significantly reduced the myotoxicity of the venom, as evident by the reduction of serum creatin kinase and lactate dehydrogenase activities. Though the extract completely inhibited in vitro PLA2 activity, it was unable to completely inhibit in situ hemolytic and in vivo edema-inducing activities, usually brought about by PLA2s. In lethality studies, co-injection of the venom preincubated with the extract showed higher protection than the independent injection of venom, followed by the extract in the mice. However, in both the cases the extract -a cocktail of inhibitors significantly increased the survival time, when compared to that of mice injected (i.p) with the venom alone. These results encourage further studies on the potential use of cocktail of inhibitors in improving the treatment of snake envenomation. Further, this study substantiates the use of M. indica as an antidote against snakebite by the traditional healers.

  1. Amphibian populations in the terrestrial environment: Is there evidence of declines of terrestrial forest amphibians in northwestern California?

    Science.gov (United States)

    Welsh, H.H.; Fellers, G.M.; Lind, A.J.

    2007-01-01

    Amphibian declines have been documented worldwide; however the vast majority are species associated with aquatic habitats. Information on the status and trends of terrestrial amphibians is almost entirely lacking. Here we use data collected across a 12-yr period (sampling from 1984-86 and from 1993-95) to address the question of whether evidence exists for declines among terrestrial amphibians in northwestern California forests. The majority of amphibians, both species and relative numbers, in these forests are direct-developing salamanders of the family Plethodontidae. We examined amphibian richness and evenness, and the relative abundances of the four most common species of plethodontid salamanders. We examined evidence of differences between years in two ecological provinces (coastal and interior) and across young, mature, and late seral forests and with reference to a moisture gradient from xeric to hydric within late seral forests. We found evidence of declines in species richness across years on late seral mesic stands and in the coastal ecological province, but these differences appeared to be caused by differences in the detection of rarer species, rather than evidence of an overall pattern. We also found differences among specific years in numbers of individuals of the most abundant species, Ensatina eschscholtzii, but these differences also failed to reflect a consistent pattern of declines between the two decadal sample periods. Results showing differences in richness, evenness, and relative abundances along both the seral and moisture continua were consistent with previous research. Overall, we found no compelling evidence of a downward trend in terrestrial plethodontid salamanders. We believe that continued monitoring of terrestrial salamander populations is important to understanding mechanisms of population declines in amphibian species. Copyright 2007 Society for the Study of Amphibians and Reptiles.

  2. Investigating the Influence of Environmental Factors on Pesticide Exposure in Amphibians

    Science.gov (United States)

    Environmental factors such as temporal weather patterns and soil characterization coupled with pesticide application rates are known to influence exposure and subsequent absorption of these compounds in amphibians. Amphibians are a unique class of vertebrates due to their varied ...

  3. Technetium-99m labeling of tityustoxin and venom from the scorpion Tityus serrulatus

    Energy Technology Data Exchange (ETDEWEB)

    Nunan, E.A.; Cardoso, V.N.; Moraes-Santos, T. E-mail: tmoraes@dedalus.lcc.ufmg.br

    2002-12-01

    The tityustoxin, the most toxic fraction from scorpion Tityus serrulatus venom, has been used as a tool in several neurochemical and neuropharmacological studies. Biological activities of labeled and unlabeled tityustoxin and venom were compared. The samples were labeled in the presence of stannous chloride and sodium borohydride with a yield of 60-70% for the venom and 75-85% for tityustoxin and then chromatographed in Sephadex G-10. Biological activities of tityustoxin and venom were preserved after labeling.

  4. The cause of global amphibian declines: a developmental endocrinologist's perspective.

    Science.gov (United States)

    Hayes, T B; Falso, P; Gallipeau, S; Stice, M

    2010-03-15

    Greater than 70% of the world's amphibian species are in decline. We propose that there is probably not a single cause for global amphibian declines and present a three-tiered hierarchical approach that addresses interactions among and between ultimate and proximate factors that contribute to amphibian declines. There are two immediate (proximate) causes of amphibian declines: death and decreased recruitment (reproductive failure). Although much attention has focused on death, few studies have addressed factors that contribute to declines as a result of failed recruitment. Further, a great deal of attention has focused on the role of pathogens in inducing diseases that cause death, but we suggest that pathogen success is profoundly affected by four other ultimate factors: atmospheric change, environmental pollutants, habitat modification and invasive species. Environmental pollutants arise as likely important factors in amphibian declines because they have realized potential to affect recruitment. Further, many studies have documented immunosuppressive effects of pesticides, suggesting a role for environmental contaminants in increased pathogen virulence and disease rates. Increased attention to recruitment and ultimate factors that interact with pathogens is important in addressing this global crisis.

  5. Control of respiration in fish, amphibians and reptiles

    Directory of Open Access Journals (Sweden)

    E.W. Taylor

    2010-05-01

    Full Text Available Fish and amphibians utilise a suction/force pump to ventilate gills or lungs, with the respiratory muscles innervated by cranial nerves, while reptiles have a thoracic, aspiratory pump innervated by spinal nerves. However, fish can recruit a hypobranchial pump for active jaw occlusion during hypoxia, using feeding muscles innervated by anterior spinal nerves. This same pump is used to ventilate the air-breathing organ in air-breathing fishes. Some reptiles retain a buccal force pump for use during hypoxia or exercise. All vertebrates have respiratory rhythm generators (RRG located in the brainstem. In cyclostomes and possibly jawed fishes, this may comprise elements of the trigeminal nucleus, though in the latter group RRG neurons have been located in the reticular formation. In air-breathing fishes and amphibians, there may be separate RRG for gill and lung ventilation. There is some evidence for multiple RRG in reptiles. Both amphibians and reptiles show episodic breathing patterns that may be centrally generated, though they do respond to changes in oxygen supply. Fish and larval amphibians have chemoreceptors sensitive to oxygen partial pressure located on the gills. Hypoxia induces increased ventilation and a reflex bradycardia and may trigger aquatic surface respiration or air-breathing, though these latter activities also respond to behavioural cues. Adult amphibians and reptiles have peripheral chemoreceptors located on the carotid arteries and central chemoreceptors sensitive to blood carbon dioxide levels. Lung perfusion may be regulated by cardiac shunting and lung ventilation stimulates lung stretch receptors.

  6. Control of respiration in fish, amphibians and reptiles

    Directory of Open Access Journals (Sweden)

    E.W. Taylor

    Full Text Available Fish and amphibians utilise a suction/force pump to ventilate gills or lungs, with the respiratory muscles innervated by cranial nerves, while reptiles have a thoracic, aspiratory pump innervated by spinal nerves. However, fish can recruit a hypobranchial pump for active jaw occlusion during hypoxia, using feeding muscles innervated by anterior spinal nerves. This same pump is used to ventilate the air-breathing organ in air-breathing fishes. Some reptiles retain a buccal force pump for use during hypoxia or exercise. All vertebrates have respiratory rhythm generators (RRG located in the brainstem. In cyclostomes and possibly jawed fishes, this may comprise elements of the trigeminal nucleus, though in the latter group RRG neurons have been located in the reticular formation. In air-breathing fishes and amphibians, there may be separate RRG for gill and lung ventilation. There is some evidence for multiple RRG in reptiles. Both amphibians and reptiles show episodic breathing patterns that may be centrally generated, though they do respond to changes in oxygen supply. Fish and larval amphibians have chemoreceptors sensitive to oxygen partial pressure located on the gills. Hypoxia induces increased ventilation and a reflex bradycardia and may trigger aquatic surface respiration or air-breathing, though these latter activities also respond to behavioural cues. Adult amphibians and reptiles have peripheral chemoreceptors located on the carotid arteries and central chemoreceptors sensitive to blood carbon dioxide levels. Lung perfusion may be regulated by cardiac shunting and lung ventilation stimulates lung stretch receptors.

  7. Control of respiration in fish, amphibians and reptiles.

    Science.gov (United States)

    Taylor, E W; Leite, C A C; McKenzie, D J; Wang, T

    2010-05-01

    Fish and amphibians utilise a suction/force pump to ventilate gills or lungs, with the respiratory muscles innervated by cranial nerves, while reptiles have a thoracic, aspiratory pump innervated by spinal nerves. However, fish can recruit a hypobranchial pump for active jaw occlusion during hypoxia, using feeding muscles innervated by anterior spinal nerves. This same pump is used to ventilate the air-breathing organ in air-breathing fishes. Some reptiles retain a buccal force pump for use during hypoxia or exercise. All vertebrates have respiratory rhythm generators (RRG) located in the brainstem. In cyclostomes and possibly jawed fishes, this may comprise elements of the trigeminal nucleus, though in the latter group RRG neurons have been located in the reticular formation. In air-breathing fishes and amphibians, there may be separate RRG for gill and lung ventilation. There is some evidence for multiple RRG in reptiles. Both amphibians and reptiles show episodic breathing patterns that may be centrally generated, though they do respond to changes in oxygen supply. Fish and larval amphibians have chemoreceptors sensitive to oxygen partial pressure located on the gills. Hypoxia induces increased ventilation and a reflex bradycardia and may trigger aquatic surface respiration or air-breathing, though these latter activities also respond to behavioural cues. Adult amphibians and reptiles have peripheral chemoreceptors located on the carotid arteries and central chemoreceptors sensitive to blood carbon dioxide levels. Lung perfusion may be regulated by cardiac shunting and lung ventilation stimulates lung stretch receptors.

  8. The importance of cartilage to amphibian development and evolution.

    Science.gov (United States)

    Rose, Christopher S

    2014-01-01

    The duality of amphibians is epitomized by their pharyngeal arch skeletons, the larval and adult morphologies of which enable very different feeding and breathing behaviors in aquatic and terrestrial life. To accomplish this duality, amphibian pharyngeal arch skeletons undergo two periods of patterning: embryogenesis and metamorphosis, and two periods of growth: larval and postmetamorphic. Their extreme ontogenetic variation, however, is coupled with relatively limited phylogenetic variation. I propose that amphibians face an evolutionary tradeoff between their ontogenetic and phylogenetic diversification that stems from the need to grow and transform the pharyngeal arch skeleton in cartilage rather than bone. Cartilage differs fundamentally from bone in its histology, function, development and growth. Cartilage is also the first skeletal tissue to form embryonically and provides more cellular pathways for shape change than bone. This article combines morphological, histological and experimental perspectives to explore how pharyngeal arch cartilage shape is controlled in amphibian embryogenesis, growth and metamorphosis, and how amphibian skeletal ontogenies are impacted by using cartilage to evolve a complex life cycle and in evolving away from a complex life cycle.

  9. A multilocus timescale for the origin of extant amphibians.

    Science.gov (United States)

    San Mauro, Diego

    2010-08-01

    One of the most hotly debated topics in vertebrate evolution is the origin of extant amphibians (Lissamphibia). The recent contribution of molecular data is shedding new light on this debate, but many important questions still remain unresolved. I have assembled a large and comprehensive multilocus dataset (the largest to date in terms of number and heterogeneity of sequence characters) combining mitogenomic and nuclear information from 23 genes for a sufficiently dense taxon sampling with the key major lineages of extant amphibians. This dataset has been used to infer a robust phylogenetic framework and molecular timescale for the origin of extant amphibians employing the most recent phylogenetic and dating methods, as well as several alternative calibration schemes. The monophyly of each extant amphibian order and the sister group relationship between frogs and salamanders (Batrachia hypothesis) are all strongly supported. Dating analyses (all methods and calibration schemes used) suggest that the origin of extant amphibians (divergence between caecilian and batrachians) occurred in the Late Carboniferous, around 315 Mya, and the divergence between frogs and salamanders occurred in the Early Permian, around 290 Mya. These age estimates are more consistent with the fossil record than previous older estimates, and more in line with the Temnospondyli or the Lepospondyli hypotheses of lissamphibian ancestry (although the polyphyly hypothesis cannot be completely ruled out).

  10. Annual Report: 2014: Partners in Amphibian and Reptile Conservation (PARC)

    Science.gov (United States)

    Weir, Linda A.; Nanjappa, P.; Apodaca, J. J.; Williams, J.

    2015-01-01

    Partners in Amphibian and Reptile Conservation (PARC) was established in 1999 to address the widespread declines, extinctions, and range reductions of amphibians and reptiles, with a focus on conservation of taxa and habitats in North America. Amphibians and reptiles are affected by a broad range of human activities, both as incidental effects of habitat alteration and direct effects from overexploitation; these animals are also burdened by humans attitudes – that amphibians and reptiles are either dangerous or of little environmental or economic value. However, PARC members understand these taxa are important parts of our natural and cultural heritage and they serve important roles in ecosystems throughout the world. With many amphibians and reptiles classified as threatened with extinction, conservation to ensure healthy populations of these animals has never been more important. As you will see herein, PARC’s 15th anniversary has been marked with major accomplishments and an ever-increasing momentum. With your help, PARC can continue to build on its successes and protect these vital species.

  11. Partial purification of Chironex fleckeri (sea wasp) venom by immunochromatography with antivenom.

    Science.gov (United States)

    Calton, G J; Burnett, J W

    1986-01-01

    Chironex fleckeri crude venom was partially purified using immobilized commercially available ovoid antivenom. The antibody preparation reacted with lethal, hemolytic, dermonecrotic and mouse writhing (pain) factors in the crude venom. The lethal activity was purified five fold, while the specific eluate contained lower quantities of hemolytic, dermonecrotic and mouse writhing activities than did the crude venom.

  12. Intraspecific Variation of Centruroides Edwardsii Venom from Two Regions of Colombia

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    Sebastián Estrada-Gómez

    2014-07-01

    Full Text Available We report the first description studies, partial characterization, and intraspecific difference of Centruroides edwardsii, Gervais 1843, venom. C. edwardsii from two Colombian regions (Antioquia and Tolima were evaluated. Both venoms showed hemolytic activity, possibly dependent of enzymatic active phospholipases, and neither coagulant nor proteolytic activities were observed. Venom electrophoretic profile showed significant differences between C. edwardsii venom from both regions. A high concentration of proteins with molecular masses between 31 kDa and 97.4 kDa, and an important concentration close or below 14.4 kDa were detected. RP-HPLC retention times between 38.2 min and 42.1 min, showed bands close to 14.4 kDa, which may correspond to phospholipases. RP-HPLC venom profile showed a well conserved region in both venoms between 7 and 17 min, after this, significant differences were detected. From Tolima region venom, 50 well-defined peaks were detected, while in the Antioquia region venom, 55 well-defined peaks were detected. Larvicidal activity was only detected in the C. edwardsii venom from Antioquia. No antimicrobial activity was observed using complete venom or RP-HPLC collected fractions of both venoms. Lethally activity (carried out on female albino swiss mice was detected at doses over 19.2 mg/kg of crude venom. Toxic effects included distress, excitability, eye irritation and secretions, hyperventilation, ataxia, paralysis, and salivation.

  13. Qualitative risk analysis of introducing Batrachochytrium dendrobatidis to the UK through the importation of live amphibians.

    Science.gov (United States)

    Peel, Alison J; Hartley, Matt; Cunningham, Andrew A

    2012-03-20

    The international amphibian trade is implicated in the emergence and spread of the amphibian fungal disease chytridiomycosis, which has resulted in amphibian declines and extinctions globally. The establishment of the causal pathogen, Batrachochytrium dendrobatidis (Bd), in the UK could negatively affect the survival of native amphibian populations. In recognition of the ongoing threat that it poses to amphibians, Bd was recently included in the World Organisation for Animal Health Aquatic Animal Health Code, and therefore is in the list of international notifiable diseases. Using standardised risk analysis guidelines, we investigated the likelihood that Bd would be introduced to and become established in wild amphibians in the UK through the importation of live amphibians. We obtained data on the volume and origin of the amphibian trade entering the UK and detected Bd infection in amphibians being imported for the pet and private collection trade and also in amphibians already held in captive pet, laboratory and zoological collections. We found that current systems for recording amphibian trade into the UK underestimate the volume of non-European Union trade by almost 10-fold. We identified high likelihoods of entry, establishment and spread of Bd in the UK and the resulting major overall impact. Despite uncertainties, we determined that the overall risk estimation for the introduction of Bd to the UK through the importation of live amphibians is high and that risk management measures are required, whilst ensuring that negative effects on legal trade are minimised.

  14. progress and prospects for studies on chinese amphibians

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    this work summarizes the history and progress of the studies on chinese amphibians since they first appeared in the chinese literature.a wide range of research has been carried out,including the history of the definition of amphibians,faunal surveys,systematic research,ecological research,biochemical research (isozyme and other proteins or peptides,chromosomes,dna),anatomical research,embryological research,phylogenetic and zoogeographical research,and many others such as ultrastructure of organs,crossbreeding test,regeneration of organs,abnormality survey,acoustics,fossils,sperm ultrastructure and parasites.in addition,the prospects for studies on chinese amphibians in future are proposed in this paper.

  15. Amphibians of the Simbruini Mountains (Latium, Central Italy

    Directory of Open Access Journals (Sweden)

    Pierangelo Crucitti

    2010-07-01

    Full Text Available Little attention has been paid to the herpetological fauna of the Simbruini Mountains Regional Park, Latium (Central Italy. In this study, we surveyed 50 sites in the course of about ten years of field research, especially during the period 2005-2008. Nine amphibian species, four Caudata and five Anura, 60.0% out of the 15 amphibian species so far observed in Latium, were discovered in the protected area: Salamandra salamandra, Salamandrina perspicillata, Lissotriton vulgaris, Triturus carnifex, Bombina pachypus, Bufo balearicus, Bufo bufo, Rana dalmatina, Rana italica. Physiography of sites has been detailed together with potential threatening patterns. For each species the following topics have been discussed; ecology of sites, altitudinal distribution, phenology, sintopy. Salamandra salamandra and Bombina pachypus are at higher risk. The importance of the maintenance of artificial/natural water bodies for the conservation management of amphibian population of this territory is discussed.

  16. Global Amphibian Extinction Risk Assessment for the Panzootic Chytrid Fungus

    Directory of Open Access Journals (Sweden)

    Matthew C. Fisher

    2009-09-01

    Full Text Available Species are being lost at increasing rates due to anthropogenic effects, leading to the recognition that we are witnessing the onset of a sixth mass extinction. Emerging infectious disease has been shown to increase species loss and any attempts to reduce extinction rates need to squarely confront this challenge. Here, we develop a procedure for identifying amphibian species that are most at risk from the effects of chytridiomycosis by combining spatial analyses of key host life-history variables with the pathogen's predicted distribution. We apply our rule set to the known global diversity of amphibians in order to prioritize pecies that are most at risk of loss from disease emergence. This risk assessment shows where limited conservation funds are best deployed in order to prevent further loss of species by enabling ex situ amphibian salvage operations and focusing any potential disease mitigation projects.

  17. The invasive chytrid fungus of amphibians paralyzes lymphocyte responses.

    Science.gov (United States)

    Fites, J Scott; Ramsey, Jeremy P; Holden, Whitney M; Collier, Sarah P; Sutherland, Danica M; Reinert, Laura K; Gayek, A Sophia; Dermody, Terence S; Aune, Thomas M; Oswald-Richter, Kyra; Rollins-Smith, Louise A

    2013-10-18

    The chytrid fungus, Batrachochytrium dendrobatidis, causes chytridiomycosis and is a major contributor to global amphibian declines. Although amphibians have robust immune defenses, clearance of this pathogen is impaired. Because inhibition of host immunity is a common survival strategy of pathogenic fungi, we hypothesized that B. dendrobatidis evades clearance by inhibiting immune functions. We found that B. dendrobatidis cells and supernatants impaired lymphocyte proliferation and induced apoptosis; however, fungal recognition and phagocytosis by macrophages and neutrophils was not impaired. Fungal inhibitory factors were resistant to heat, acid, and protease. Their production was absent in zoospores and reduced by nikkomycin Z, suggesting that they may be components of the cell wall. Evasion of host immunity may explain why this pathogen has devastated amphibian populations worldwide.

  18. Phylogeny-based comparative analysis of venom proteome variation in a clade of rattlesnakes (Sistrurus sp..

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    H Lisle Gibbs

    Full Text Available A long-standing question in evolutionary studies of snake venoms is the extent to which phylogenetic divergence and diet can account for between-species differences in venom composition. Here we apply phylogeny-based comparative methods to address this question. We use data on venom variation generated using proteomic techniques for all members of a small clade of rattlesnakes (Sistrurus sp. and two outgroups for which phylogenetic and diet information is available. We first complete the characterization of venom variation for all members of this clade with a "venomic" analysis of pooled venoms from two members of this genus, S. milarius streckeri and S. m. milarius. These venoms exhibit the same general classes of proteins as those found in other Sistrurus species but differ in their relative abundances of specific protein families. We then test whether there is significant phylogenetic signal in the relative abundances of major venom proteins across species and if diet (measured as percent mammals and lizards among all prey consumed covaries with venom composition after phylogenetic divergence is accounted for. We found no evidence for significant phylogenetic signal in venom variation: K values for seven snake venom proteins and two composite venom variables [PC 1 and 2] were all nonsignificant and lower (mean = 0.11+0.06 sd than mean K values (>0.35 previously reported for a wide range of morphological, life history, physiological and behavioral traits from other species. Finally, analyses based on Phylogenetic Generalized Least Squares (PGLS methods reveal that variation in abundance of some venom proteins, most strongly CRISP is significantly related to snake diet. Our results demonstrate that venom variation in these snakes is evolutionarily a highly labile trait even among very closely-related taxa and that natural selection acting through diet variation may play a role in molding the relative abundance of specific venom proteins.

  19. Muscle regeneration in amphibians and mammals: passing the torch.

    Science.gov (United States)

    Carlson, Bruce M

    2003-02-01

    Skeletal muscle in both amphibians and mammals possesses a high regenerative capacity. In amphibians, a muscle can regenerate in two distinct ways: as a tissue component of an entire regenerating limb (epimorphic regeneration) or as an isolated entity (tissue regeneration). In the absence of epimorphic regenerative ability, mammals can regenerate muscles only by the tissue mode. This review focuses principally on the regeneration of entire muscles and covers what is known and what remains to be elucidated about fundamental mechanisms underlying muscle regeneration at this level.

  20. Amphibian decline: An integrated analysis of multiple stressor effects

    Science.gov (United States)

    Linder, G.; Krest, S.K.; Sparling, D. W.; Linder, G.; Krest, S.K.; Sparling, D.W.

    2003-01-01

    Capturing the attention and imagination of the public and the scientific community alike, the mysterious decline in amphibian populations drew scientists and resource managers from ecotoxicology and chemistry, ecology and field biology, conservation biology, and natural resource policy to a SETAC–Johnson Foundation workshop. Facilitating environmental stewardship, increasing capacity of the sciences to explain complex stressors, and educating the public on relationships among communities of all types motivated these experts to address amphibian decline and the role of various stressors in these losses.

  1. The Amphibian Research and Monitoring Initiative in the Pacific Northwest

    Science.gov (United States)

    Adams, Michael J.

    2003-01-01

    Amphibians have been disappearing from many locations around the world with reports of declines increasing in recent decades. Some of the most dramatic declines have occurred in areas that were thought to be protected from human disturbance. For example, the once-common boreal toad has virtually disappeared from Rocky Mountain National Park in Colorado. Although there has been debate on whether these declines represent a short-term fluctuation in populations or major sustained losses, there is now general scientific consensus that something really is amiss with amphibian populations.

  2. Facing Hymenoptera Venom Allergy: From Natural to Recombinant Allergens

    Directory of Open Access Journals (Sweden)

    Amilcar Perez-Riverol

    2015-07-01

    Full Text Available Along with food and drug allergic reactions, a Hymenoptera insect Sting (Apoidea, Vespidae, Formicidae is one of the most common causes of anaphylaxis worldwide. Diagnoses of Hymenoptera venom allergy (HVA and specific immunotherapy (SIT have been based on the use of crude venom extracts. However, the incidence of cross-reactivity and low levels of sensibility during diagnosis, as well as the occurrence of nonspecific sensitization and undesired side effects during SIT, encourage the search for novel allergenic materials. Recombinant allergens are an interesting approach to improve allergy diagnosis and SIT because they circumvent major problems associated with the use of crude venom. Production of recombinant allergens depends on the profound molecular characterization of the natural counterpart by combining some “omics” approaches with high-throughput screening techniques and the selection of an appropriate system for heterologous expression. To date, several clinically relevant allergens and novel venom toxins have been identified, cloned and characterized, enabling a better understanding of the whole allergenic and envenoming processes. Here, we review recent findings on identification, molecular characterization and recombinant expression of Hymenoptera venom allergens and on the evaluation of these heterologous proteins as valuable tools for tackling remaining pitfalls on HVA diagnosis and immunotherapy.

  3. Exon Shuffling and Origin of Scorpion Venom Biodiversity

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    Xueli Wang

    2016-12-01

    Full Text Available Scorpion venom is a complex combinatorial library of peptides and proteins with multiple biological functions. A combination of transcriptomic and proteomic techniques has revealed its enormous molecular diversity, as identified by the presence of a large number of ion channel-targeted neurotoxins with different folds, membrane-active antimicrobial peptides, proteases, and protease inhibitors. Although the biodiversity of scorpion venom has long been known, how it arises remains unsolved. In this work, we analyzed the exon-intron structures of an array of scorpion venom protein-encoding genes and unexpectedly found that nearly all of these genes possess a phase-1 intron (one intron located between the first and second nucleotides of a codon near the cleavage site of a signal sequence despite their mature peptides remarkably differ. This observation matches a theory of exon shuffling in the origin of new genes and suggests that recruitment of different folds into scorpion venom might be achieved via shuffling between body protein-coding genes and ancestral venom gland-specific genes that presumably contributed tissue-specific regulatory elements and secretory signal sequences.

  4. Facing Hymenoptera Venom Allergy: From Natural to Recombinant Allergens.

    Science.gov (United States)

    Perez-Riverol, Amilcar; Justo-Jacomini, Débora Lais; Zollner, Ricardo de Lima; Brochetto-Braga, Márcia Regina

    2015-07-09

    Along with food and drug allergic reactions, a Hymenoptera insect Sting (Apoidea, Vespidae, Formicidae) is one of the most common causes of anaphylaxis worldwide. Diagnoses of Hymenoptera venom allergy (HVA) and specific immunotherapy (SIT) have been based on the use of crude venom extracts. However, the incidence of cross-reactivity and low levels of sensibility during diagnosis, as well as the occurrence of nonspecific sensitization and undesired side effects during SIT, encourage the search for novel allergenic materials. Recombinant allergens are an interesting approach to improve allergy diagnosis and SIT because they circumvent major problems associated with the use of crude venom. Production of recombinant allergens depends on the profound molecular characterization of the natural counterpart by combining some "omics" approaches with high-throughput screening techniques and the selection of an appropriate system for heterologous expression. To date, several clinically relevant allergens and novel venom toxins have been identified, cloned and characterized, enabling a better understanding of the whole allergenic and envenoming processes. Here, we review recent findings on identification, molecular characterization and recombinant expression of Hymenoptera venom allergens and on the evaluation of these heterologous proteins as valuable tools for tackling remaining pitfalls on HVA diagnosis and immunotherapy.

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

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    JVR Rivero

    2011-01-01

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

  6. The toxicogenomic multiverse: convergent recruitment of proteins into animal venoms.

    Science.gov (United States)

    Fry, Bryan G; Roelants, Kim; Champagne, Donald E; Scheib, Holger; Tyndall, Joel D A; King, Glenn F; Nevalainen, Timo J; Norman, Janette A; Lewis, Richard J; Norton, Raymond S; Renjifo, Camila; de la Vega, Ricardo C Rodríguez

    2009-01-01

    Throughout evolution, numerous proteins have been convergently recruited into the venoms of various animals, including centipedes, cephalopods, cone snails, fish, insects (several independent venom systems), platypus, scorpions, shrews, spiders, toxicoferan reptiles (lizards and snakes), and sea anemones. The protein scaffolds utilized convergently have included AVIT/colipase/prokineticin, CAP, chitinase, cystatin, defensins, hyaluronidase, Kunitz, lectin, lipocalin, natriuretic peptide, peptidase S1, phospholipase A(2), sphingomyelinase D, and SPRY. Many of these same venom protein types have also been convergently recruited for use in the hematophagous gland secretions of invertebrates (e.g., fleas, leeches, kissing bugs, mosquitoes, and ticks) and vertebrates (e.g., vampire bats). Here, we discuss a number of overarching structural, functional, and evolutionary generalities of the protein families from which these toxins have been frequently recruited and propose a revised and expanded working definition for venom. Given the large number of striking similarities between the protein compositions of conventional venoms and hematophagous secretions, we argue that the latter should also fall under the same definition.

  7. Characterization of Fibrinolytic Proteases from Gloydius blomhoffii siniticus Venom

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    Suk Ho Choi

    2011-09-01

    Full Text Available Objectives : This study was undertaken to identify fibrinolytic proteases from Gloydius blomhoffii siniticus venom and to characterize a major fibrinolytic protease purified from the venom. Methods: The venom was subjected to chromatography using columns of Q-Sepharose and Sephadex G-75. The molecular weights of fibrinolytic proteases showing fibrinolytic zone in fibrin plate assay were determined in SDS-PAGE (Sodium dodecyl sulfate-polyacrylamide gel electrophoresis The effects of inhibitors and metal ions on fibrinolytic protease and the proteolysis patterns of fibrinogen, gelatin, and bovine serum albumin were investigated. Results : 1 The fibrinolytic fractions of the three peaks isolated from Gloydius blomhoffii siniticus venom contained two polypeptides of 46 and 59 kDa and three polypeptides of 32, 18, and 15 kDa and a major polypeptide of 54 kDa, respectively. 2 The fibrinolytic activity of the purified protease of 54 kDA was inhibited by metal chelators, such as EDTA, EGTA, and 1,10-phenanthroline, and disulfhydryl-reducing compounds, such as dithiothreitol and cysteine. 3 Calcium chloride promoted the fibrinolytic activity of the protease, but mercuric chloride and cobalt(II chloride inhibited it. 4 The fibrinolytic protease cleaved preferentially A-chain and slowly B-chain of fibrinogen. It also hydrolyzed gelatin but not bovine serum albumin. Conclusions: The Gloydius blomhoffii siniticus venom contained more than three fibrinolytic proteases. The major fibrinolytic protease was a metalloprotease which hydrolyzed both fibrinogen and gelatin, but not bovine serum albumin.

  8. Hemolytic activity of venom from crown-of-thorns starfish Acanthaster planci spines

    OpenAIRE

    Lee, Chi-Chiu; Tsai, Wann-Sheng; Hsieh, Hernyi Justin; Hwang, Deng-Fwu

    2013-01-01

    Background The crown-of-thorns starfish Acanthaster planci is a venomous species from Taiwan whose venom provokes strong hemolytic activity. To understand the hemolytic properties of A. planci venom, samples were collected from A. planci spines in the Penghu Islands, dialyzed with distilled water, and lyophilized into A. planci spine venom (ASV) powder. Results Both crude venom and ASV cause 50% hemolysis at a concentration of 20 μg/mL. The highest hemolytic activity of ASV was measured at pH...

  9. Mechanisms controlling venom expulsion in the western diamondback rattlesnake, Crotalus atrox.

    Science.gov (United States)

    Young, Bruce A; Kardong, Kenneth V

    2007-01-01

    Although many studies have documented variation in the amount of venom expended during bites of venomous snakes, the mechanistic source of this variation remains uncertain. This study used experimental techniques to examine how two different features of the venom delivery system, the muscle surrounding the venom gland (the Compressor Glandulae in the rattlesnake) and the fang sheath, could influence venom flow in the western diamondback rattlesnake, Crotalus atrox. Differential contraction of the Compressor Glandulae explained only approximately 30% of the variation in venom flow. Lifting (compression) of the fang sheath as occurs during a normal strike produced marked increases in venom flow; these changes were closely correlated and exceed in magnitude by almost 10 x those recorded from the Compressor Glandulae alone. These results suggest that variation in these two aspects of the venom delivery system--both in terms of magnitude and temporal patterning--explain most of the observed variation in venom injection. The lack of functional or mechanical links between the Compressor Glandulae and the fang sheath, and the lack of skeletal or smooth muscle within the fang sheath, make it unlikely that variation in venom flow is under direct neural control. Instead, differential venom injection results from differences in the pressurization by the Compressor Glandulae, the gate keeping effects of the fang sheath and enclosed soft-tissue chambers, and by differences in the pressure returned by peripheral resistance of the target tissue.

  10. The Triterpenoid Betulin Protects against the Neuromuscular Effects of Bothrops jararacussu Snake Venom In Vivo

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    Miriéle Cristina Ferraz

    2015-01-01

    Full Text Available We confirmed the ability of the triterpenoid betulin to protect against neurotoxicity caused by Bothrops jararacussu snake venom in vitro in mouse isolated phrenic nerve-diaphragm (PND preparations and examined its capability of in vivo protection using the rat external popliteal/sciatic nerve-tibialis anterior (EPSTA preparation. Venom caused complete, irreversible blockade in PND (40 μg/mL, but only partial blockade (~30% in EPSTA (3.6 mg/kg, i.m. after 120 min. In PND, preincubation of venom with commercial bothropic antivenom (CBA attenuated the venom-induced blockade, and, in EPSTA, CBA given i.v. 15 min after venom also attenuated the blockade (by ~70% in both preparations. Preincubation of venom with betulin (200 μg/mL markedly attenuated the venom-induced blockade in PND; similarly, a single dose of betulin (20 mg, i.p., 15 min after venom virtually abolished the venom-induced decrease in contractility. Plasma creatine kinase activity was significantly elevated 120 min after venom injection in the EPSTA but was attenuated by CBA and betulin. These results indicate that betulin given i.p. has a similar efficacy as CBA given i.v. in attenuating the neuromuscular effects of B. jararacussu venom in vivo and could be a useful complementary measure to antivenom therapy for treating snakebite.

  11. The Triterpenoid Betulin Protects against the Neuromuscular Effects of Bothrops jararacussu Snake Venom In Vivo

    Science.gov (United States)

    Ferraz, Miriéle Cristina; de Oliveira, Jhones Luiz; de Oliveira Junior, Joel Reis; Cogo, José Carlos; dos Santos, Márcio Galdino; Franco, Luiz Madaleno; Puebla, Pilar; Ferraz, Helena Onishi; Ferraz, Humberto Gomes; da Rocha, Marisa Maria Teixeira; Hyslop, Stephen; San Feliciano, Arturo; Oshima-Franco, Yoko

    2015-01-01

    We confirmed the ability of the triterpenoid betulin to protect against neurotoxicity caused by Bothrops jararacussu snake venom in vitro in mouse isolated phrenic nerve-diaphragm (PND) preparations and examined its capability of in vivo protection using the rat external popliteal/sciatic nerve-tibialis anterior (EPSTA) preparation. Venom caused complete, irreversible blockade in PND (40 μg/mL), but only partial blockade (~30%) in EPSTA (3.6 mg/kg, i.m.) after 120 min. In PND, preincubation of venom with commercial bothropic antivenom (CBA) attenuated the venom-induced blockade, and, in EPSTA, CBA given i.v. 15 min after venom also attenuated the blockade (by ~70% in both preparations). Preincubation of venom with betulin (200 μg/mL) markedly attenuated the venom-induced blockade in PND; similarly, a single dose of betulin (20 mg, i.p., 15 min after venom) virtually abolished the venom-induced decrease in contractility. Plasma creatine kinase activity was significantly elevated 120 min after venom injection in the EPSTA but was attenuated by CBA and betulin. These results indicate that betulin given i.p. has a similar efficacy as CBA given i.v. in attenuating the neuromuscular effects of B. jararacussu venom in vivo and could be a useful complementary measure to antivenom therapy for treating snakebite. PMID:26633987

  12. Analysis of Protein Composition and Bioactivity of Neoponera villosa Venom (Hymenoptera: Formicidae

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    Wallace Felipe Blohem Pessoa

    2016-04-01

    Full Text Available Ants cause a series of accidents involving humans. Such accidents generate different reactions in the body, ranging from a mild irritation at the bite site to anaphylactic shock, and these reactions depend on the mechanism of action of the venom. The study of animal venom is a science known as venomics. Through venomics, the composition of the venom of several ant species has already been characterized and their biological activities described. Thus, the aim of this study was to evaluate the protein composition and biological activities (hemolytic and immunostimulatory of the venom of Neoponera villosa (N. villosa, an ant widely distributed in South America. The protein composition was evaluated by proteomic techniques, such as two-dimensional electrophoresis. To assess the biological activity, hemolysis assay was carried out and cytokines were quantified after exposure of macrophages to the venom. The venom of N. villosa has a profile composed of 145 proteins, including structural and metabolic components (e.g., tubulin and ATPase, allergenic and immunomodulatory proteins (arginine kinase and heat shock proteins (HSPs, protective proteins of venom (superoxide dismutase (SOD and catalase and tissue degradation proteins (hyaluronidase and phospholipase A2. The venom was able to induce hemolysis in human erythrocytes and also induced release of both pro-inflammatory cytokines, as the anti-inflammatory cytokine release by murine macrophages. These results allow better understanding of the composition and complexity of N. villosa venom in the human body, as well as the possible mechanisms of action after the bite.

  13. The in vitro vascular effects of two chirodropid (Chironex fleckeri and Chiropsella bronzie) venoms.

    Science.gov (United States)

    Winter, Kelly L; Fernando, Ross; Ramasamy, Sharmaine; Seymour, Jamie E; Isbister, Geoffrey K; Hodgson, Wayne C

    2007-01-10

    Clinical observations suggest a primary cardiotoxic role in fatal Chironex fleckeri stings. The limited research available indicates that Chiropsella bronzie venom acts in a similar manner although appears to be less potent. The aim of the present study was to elucidate the vascular effects of C. fleckeri and C. bronzie venoms using rat isolated aorta. Both venoms produced a sustained contraction of endothelium-denuded aorta which was not significantly affected by prazosin or box jellyfish antivenom. Felodipine significantly reduced the contractile response to C. fleckeri venom but not C. bronzie venom. Both venoms produced an initial relaxation (Phase 1), followed by a sustained contraction (Phase 2), in pre-contracted endothelium-intact aorta. Removal of the endothelium significantly inhibited both phases of the response. NOLA significantly inhibited Phase 1, but not Phase 2, of the response to both venoms. Atropine, HOE 140 or BQ 123 did not have any significant inhibitory effect on either phase. In conclusion, neither C. fleckeri nor C. bronzie venoms appear to contain components with activity at alpha(1)-adrenoceptors. Antivenom was ineffective in reversing the effects of the venom suggesting it is incapable of completely neutralising nematocyst-derived venom. Determining the mechanism of action of these venoms will allow for the development of better treatment strategies.

  14. Antigenic Cross-Reactivity Anti-Birtoxin Antibody against Androctonus crassicauda Venom

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    SuhandanAdigüzel Van-Zoelen

    2015-10-01

    Full Text Available Background: Antivenom is still widely used in the treatment of envenomation as there are no vaccines or other effective agents available against animal venoms. Recently, neurotoxins named birtoxin family have been described from Parabuthus transvaalicus and Androctonus crassicauda. The aim of the present study was to test the antibirtoxinantibodies for their ability to neutralize the lethal effects of A. crassicauda scorpion venom.Methods: SDS-PAGE and Western blotting used the presence of components from A. crassicauda and P.transvaalicus scorpion venoms and to determine the degree of cross-reactivity. The Minimum Lethal Dose (MLD of venom was assessed by subcutaneously (sc injections in mice.Results: The MLD of the A. crassicauda venom was 35 μg/ 20g mouse by sc injection route. Western blotting showed the presence of components from A. crassicauda and P. transvaalicus scorpion venoms strongly cross react with the A. crassicauda antivenom. However, Western blotting of the A. crassicauda scorpion venom using the Refik Saydam Public Health Agency (RSPHA generated antibody showed that not all the venom components cross reacted with the anti-birtoxin antibody. The antibodies only cross reacted with components falling under the 19 kDa protein size of A. crassicauda venom.Conclusion: The bioassays and Western blotting of A. crassicauda venom with the anti-birtoxin antibodies produced against a synthetic peptide showed that these antibodies cross reacted but did not neutralize the venom of A. crassicauda.

  15. Intersexual variations in Northern (Missulena pruinosa) and Eastern (M. bradleyi) mouse spider venom.

    Science.gov (United States)

    Herzig, Volker; Khalife, Ali A; Chong, Youmie; Isbister, Geoffrey K; Currie, Bart J; Churchill, Tracey B; Horner, Suzanne; Escoubas, Pierre; Nicholson, Graham M; Hodgson, Wayne C

    2008-06-01

    Venoms of both sexes of Australian Northern (Missulena pruinosa) and Eastern (Missulena bradleyi) mouse spiders were studied in order to determine intersexual variations in venom yield, composition and bioactivity. Females of both species yielded more venom than males. High-performance liquid chromatography (HPLC) and mass spectrometry data further indicate a substantial degree of intersexual variation in the venom composition of both species. In a cricket (Acheta domestica) acute toxicity assay, only small intersexual differences were observed, but M. bradleyi venom was found to be considerably more potent than M. pruinosa venom. In the chick biventer cervicis nerve-muscle preparation, male but not female M. bradleyi venom induced large and sustained muscle contractions with fasciculation and decreased twitch height that could be reversed by CSL funnel-web spider antivenom. In contrast, venoms of both sexes of M. pruinosa did not induce significant effects in the chick biventer cervicis nerve-muscle preparation. We therefore conclude that female M. bradleyi venom and venoms from male and female M. pruinosa appear to contain few, if any, orthologs of delta-missulenatoxin-Mb1a, the toxin responsible for the effects of male M. bradleyi venom in vertebrates. These findings are consistent with clinical reports that mouse spiders, particularly species other than male M. bradleyi, do not appear to be a major medical problem in humans.

  16. [Pharmacologic and enzymatic effects of snake venoms from Antioquia and Choco (Colombia)].

    Science.gov (United States)

    Otero, R; Guillermo Osorio, R; Valderrama, R; Augusto Giraldo, C

    1992-01-01

    We compared several pharmacological and enzymatic effects induced by 11 snake venoms from seven species, six of them from different geographic areas of Antioquia and Choco, north-west of Colombia, South America (Bothrops atrox, B. nasutus, B. schlegelii, B. punctatus, Lachesis muta, Micrurus mipartitus), and Crotalus durissus terrificus venom, from specimens captured in other provinces of the country (Tolima, Huila, Meta and Atlantico). Differences were observed in edema-forming, hemorrhage, defibrination, indirect hemolysis, myonecrosis, proteolysis and lethal activity between venoms from different genera or species, as well as according to the geographic area of origin in B. atrox and B. nasutus snake venoms. Bothrops venoms, in particular B. atrox and L. muta, produced major local effects. All of the venoms, including M. mipartitus, had myotoxic effects. The most defibrinating venoms were B. atrox, L. muta, B. punctatus and C. d. terrificus. All of the venoms had indirect hemolytic activity; the venom of M. mipartitus being greatest. The most lethal venoms were those of C. d. terrificus and M. mipartitus. Within Bothrops species, the venom of B. schlegelii was the least active in terms of local and systemic pathologic effects.

  17. Improved sensitivity to venom specific-immunoglobulin E by spiking with the allergen component in Japanese patients suspected of Hymenoptera venom allergy

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    Naruo Yoshida

    2015-07-01

    Conclusions: The measurement of sIgE following spiking of rVes v 5 and rPol d 5 by conventional testing in Japanese subjects with sIgE against hornet and paper wasp venom, respectively, improved the sensitivity for detecting Hymenoptera venom allergy. Improvement testing for measuring sIgE levels against hornet and paper wasp venom has potential for serologically elucidating Hymenoptera allergy in Japan.

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

    Science.gov (United States)

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

    2009-11-01

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

  19. Analysis of intraspecific variation in venoms of Acanthophis antarcticus death adders from South Australia.

    Science.gov (United States)

    Herzig, Volker; Kohler, Maxie; Grund, Kai F; Reeve, Shane; Smith, A Ian; Hodgson, Wayne C

    2013-01-01

    Intraspecific variation in venom composition and activity has been reported from a wide range of snakes. Geographical origin can be one cause for this variation and has recently been documented from Acanthophis antarcticus death adders sampled across four different Australian states. The present study examined whether a narrower sampling range of A. antarcticus from four collection sites within one Australian state (i.e., South Australia) would also exhibit variation in venom composition and/or activity. The present LC-MS results reveal marked differences in the venom composition from different collection sites. The most striking difference was the reduced venom complexity found in the only venom originating from a mallee scrub habitat in comparison to the venoms from coastal heath scrub habitats. Interestingly, the pharmacological activity of all venoms was found to be the same, independent of the collection site.

  20. A rapid and repeatable method for venom extraction from cubozoan nematocysts.

    Science.gov (United States)

    Carrette, T; Seymour, J

    2004-08-01

    Various comparative studies into the biological activity and relative toxicity of cubozoan venoms have been investigated, in particular the venom from the potentially lethal cubozoan Chironex fleckeri. Efficient and reliable extraction of venom from nematocysts is essential before any research into venom toxicity can be conducted and previous cited methods of extraction have varied greatly, each with their own associated problems. A new standardised technique for the recovery of venom from nematocysts of cubozoans is investigated to decrease the variation displayed between authors due to differing extraction techniques. The use of a mini bead mill beater, as investigated in this trial, allows for the rapid extraction of venom from nematocysts and is devoid of the previously isolated problems experienced with other methods of venom isolation, such as excessive heat build up.

  1. Evaluation of antivenoms in the neutralization of hyperalgesia and edema induced by Bothrops jararaca and Bothrops asper snake venoms

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    Picolo G.

    2002-01-01

    Full Text Available Neutralization of hyperalgesia induced by Bothrops jararaca and B. asper venoms was studied in rats using bothropic antivenom produced at Instituto Butantan (AVIB, 1 ml neutralizes 5 mg B. jararaca venom and polyvalent antivenom produced at Instituto Clodomiro Picado (AVCP, 1 ml neutralizes 2.5 mg B. aspar venom. The intraplantar injection of B. jararaca and B. asper venoms caused hyperalgesia, which peaked 1 and 2 h after injection, respectively. Both venoms also induced edema with a similar time course. When neutralization assays involving the independent injection of venom and antivenom were performed, the hyperalgesia induced by B. jararaca venom was neutralized only when bothropic antivenom was administered iv 15 min before venom injection, whereas edema was neutralized when antivenom was injected 15 min or immediately before venom injection. On the other hand, polyvalent antivenom did not interfere with hyperalgesia or edema induced by B. asper venom, even when administered prior to envenomation. The lack of neutralization of hyperalgesia and edema induced by B. asper venom is not attributable to the absence of neutralizing antibodies in the antivenom, since neutralization was achieved in assays involving preincubation of venom and antivenom. Cross-neutralization of AVCP or AVIB against B. jararaca and B. asper venoms, respectively, was also evaluated. Only bothropic antivenom partially neutralized hyperalgesia induced by B. asper venom in preincubation experiments. The present data suggest that hyperalgesia and edema induced by Bothrops venoms are poorly neutralized by commercial antivenoms even when antibodies are administered immediately after envenomation.

  2. Spinal processing of bee venom-induced pain and hyperalgesia

    Institute of Scientific and Technical Information of China (English)

    Jun CHEN

    2008-01-01

    Subcutaneous injection of bee venom causes long-term neural activation and hypersensitization in the dorsal horn of the spinal cord, which contributes to the development and maintenance of various pain-related behaviors. The unique behavioral 'pheno-types' of nociception and hypersensitivity identified in the rodent bee venom test are believed to reflect a complex pathological state of inflammatory pain and might be appropriate to the study of phenotype-based mechanisms of pain and hyperalgesia. In this review, the spinal processing of the bee venom-induced different 'phenotypes' of pain and hyperalgesia will be described. The accumulative electrophysiological, pharmacological, and behavioral data strongly suggest that different 'phenotypes' of pain and hyperalgesia are mediated by different spinal signaling pathways. Unraveling the phenotype-based mechanisms of pain might be useful in development of novel therapeutic drugs against complex clinic pathological pain.

  3. Venomous snakebite in mountainous terrain: prevention and management.

    Science.gov (United States)

    Boyd, Jeff J; Agazzi, Giancelso; Svajda, Dario; Morgan, Arthur J; Ferrandis, Silvia; Norris, Robert L

    2007-01-01

    The prevention and management of venomous snakebite in the world's mountains present unique challenges. This paper presents a series of practical, clinically sound recommendations for management of venomous snakebite in a mountain environment. The authors performed an extensive review of current literature using search engines and manual searches. They then fused the abundant knowledge of snakebite with the realities of remote first aid and mountain rescue to develop recommendations. A summary is provided of the world's most troublesome mountain snakes and the mechanisms of toxicity from their bites. Preventive measures are described. Expected symptoms and signs are reviewed in lay and medical terms. A review of currently recommended first-aid measures and advanced medical management for physicians, paramedics, and other clinicians is included. Venomous snakebites in mountainous environments present unique challenges for management. This paper offers practical recommendations for managing such cases and summarizes the approach to first aid and advanced management in 2 algorithms.

  4. A Novel Neurotoxin from Venom of the Spider, Brachypelma albopilosum

    Science.gov (United States)

    Yuan, Mingwei; Li, Hongli; Wang, Ping; Yuan, Minglong; Lu, Qiumin

    2014-01-01

    Spiders have evolved highly selective toxins for insects. There are many insecticidal neurotoxins in spider venoms. Although a large amount of work has been done to focus on neurotoxicity of spider components, little information, which is related with effects of spider toxins on tumor cell proliferation and cytotoxicity, is available for Brachypelma albopilosum venom. In this work, a novel spider neurotoxin (brachyin) was identified and characterized from venoms of the spider, Brachypelma albopilosum. Brachyin is composed of 41 amino acid residues with the sequence of CLGENVPCDKDRPNCCSRYECLEPTGYGWWYASYYCYKKRS. There are six cysteines in this sequence, which form three disulfided bridges. The serine residue at the C-terminus is amidated. Brachyin showed strong lethal effects on American cockroaches (Periplaneta americana) and Tenebrio molitor (common mealbeetle). This neurotoxin also showed significant analgesic effects in mice models including abdominal writhing induced by acetic acid and formalin-induced paw licking tests. It was interesting that brachyin exerted marked inhibition on tumor cell proliferation. PMID:25329070

  5. A novel neurotoxin from venom of the spider, Brachypelma albopilosum.

    Science.gov (United States)

    Zhong, Yunhua; Song, Bo; Mo, Guoxiang; Yuan, Mingwei; Li, Hongli; Wang, Ping; Yuan, Minglong; Lu, Qiumin

    2014-01-01

    Spiders have evolved highly selective toxins for insects. There are many insecticidal neurotoxins in spider venoms. Although a large amount of work has been done to focus on neurotoxicity of spider components, little information, which is related with effects of spider toxins on tumor cell proliferation and cytotoxicity, is available for Brachypelma albopilosum venom. In this work, a novel spider neurotoxin (brachyin) was identified and characterized from venoms of the spider, Brachypelma albopilosum. Brachyin is composed of 41 amino acid residues with the sequence of CLGENVPCDKDRPNCCSRYECLEPTGYGWWYASYYCYKKRS. There are six cysteines in this sequence, which form three disulfided bridges. The serine residue at the C-terminus is amidated. Brachyin showed strong lethal effects on American cockroaches (Periplaneta americana) and Tenebrio molitor (common mealbeetle). This neurotoxin also showed significant analgesic effects in mice models including abdominal writhing induced by acetic acid and formalin-induced paw licking tests. It was interesting that brachyin exerted marked inhibition on tumor cell proliferation.

  6. The composition, biochemical properties and toxicity of snake venoms

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    Ireneusz Całkosiński

    2010-05-01

    Full Text Available 2.5 million cases of snake bites are noticed in the world every year (within 100,000 is mortal. These bites occur frequently in Asia and Africa. Some reports proved the toxicity and composition changes of well-known venoms from the same snake species according to the climatic zone. Snake venom is a natural source of many biologically active substances, including those with potential therapeutic properties. These substances contain peptides, proteins, and enzymes which are divided into five subfamilies: three-finger toxins, serine protease inhibitors of the Kunitz type, phospholipases A2, serine proteases, and metalloproteases. All snake venoms are grouped depending on their mode of action. They usually cause neurotransmission disorders, cardiotoxic action, hemostasis disorders, and have central nervous system and necrotic activity.

  7. A novel neurotoxin from venom of the spider, Brachypelma albopilosum.

    Directory of Open Access Journals (Sweden)

    Yunhua Zhong

    Full Text Available Spiders have evolved highly selective toxins for insects. There are many insecticidal neurotoxins in spider venoms. Although a large amount of work has been done to focus on neurotoxicity of spider components, little information, which is related with effects of spider toxins on tumor cell proliferation and cytotoxicity, is available for Brachypelma albopilosum venom. In this work, a novel spider neurotoxin (brachyin was identified and characterized from venoms of the spider, Brachypelma albopilosum. Brachyin is composed of 41 amino acid residues with the sequence of CLGENVPCDKDRPNCCSRYECLEPTGYGWWYASYYCYKKRS. There are six cysteines in this sequence, which form three disulfided bridges. The serine residue at the C-terminus is amidated. Brachyin showed strong lethal effects on American cockroaches (Periplaneta americana and Tenebrio molitor (common mealbeetle. This neurotoxin also showed significant analgesic effects in mice models including abdominal writhing induced by acetic acid and formalin-induced paw licking tests. It was interesting that brachyin exerted marked inhibition on tumor cell proliferation.

  8. Purification and characterization of five snake venom metalloproteinases from Egyptian Echis pyramidum pyramidum venom.

    Science.gov (United States)

    Abdel-Aty, Azza M; Wahby, Ahmed F

    2014-08-01

    New five P-III snake venom metalloproteinases (SVMPs): EpyB2 (62 kDa), EpyB3 (62+23 kDa), EpyB4 (60 kDa), EpyB5 (67 kDa) and EpyB6 (66 kDa) of the most dangerous viper, Echis pyramidum pyramidum (Epy), were purified and characterized in a set of biochemical assays. The SVMPs were purified by applying a protocol of two successive chromatographic steps. Three purified SVMPs "EpyB2, EpyB4, and EpyB5" have hemorrhagic activity with MHDs, 7 μg, 7.6 μg and 15 μg, respectively; furthermore, they have high preference towards fibronectin, collagen, gelatin, fibrin and hemoglobin substrates compared with non-hemorrhagic SVMPs (EpyB3 and EpyB6). All the purified SVMPs showed remarkable thermal and pH stability, inhibited by metalloproteinase inhibitors and Zn(2+), Mn(2+), Ni(2+), Co(2+), Cu(2+), and Hg(2+). The purified SVMPs act as α-fibrinogenases, prothrombin activators and procoagulants. In conclusion, Epy venom has multiple SVMPs that are responsible for hemorrhagic events and thus represent a significant health hazard for victims of envenomation, however, they may be useful for treating diseases involving abnormal blood clot formation.

  9. Batrachochytrium dendrobatidis infection of amphibians in the Doñana National Park, Spain.

    Science.gov (United States)

    Hidalgo-Vila, Judit; Díaz-Paniagua, Carmen; Marchand, Marc A; Cunningham, Andrew A

    2012-03-20

    Amphibian chytridiomycosis, caused by infection with the non-hyphal, zoosporic chytrid fungus Batrachochytrium dendrobatidis (Bd), is an emerging infectious disease recognised as a cause of recent amphibian population declines and extinctions worldwide. The Doñana National Park (DNP) is located in southwestern Spain, a country with widespread Bd infection. This protected area has a great diversity of aquatic habitats that constitute important breeding habitats for 11 native amphibian species. We sampled 625 amphibians in December 2007 and February to March 2008, months that correspond to the early and intermediate breeding seasons for amphibians, respectively. We found 7 of 9 sampled species to be infected with Bd and found differences in prevalence between sampling periods. Although some amphibians tested had higher intensities of infection than others, all animals sampled were apparently healthy and, so far, there has been no evidence of either unusually high rates of mortality or amphibian population declines in the DNP.

  10. Venomic study on cone snails (Conus spp.) from South Africa.

    Science.gov (United States)

    Kauferstein, Silke; Porth, Christine; Kendel, Yvonne; Wunder, Cora; Nicke, Annette; Kordis, Dusan; Favreau, Philippe; Koua, Dominique; Stöcklin, Reto; Mebs, Dietrich

    2011-01-01

    From six Conus species (Conus coronatus, Conus lividus, Conus mozambicus f. lautus, Conus pictus, Conus sazanka, Conus tinianus) collected off the eastern coast of South Africa the venoms were analyzed using MALDI-TOF mass spectrometry. Between 56 and 151 molecular masses most in a range of 1000 to 2500 Da, were identified. Among the six venoms, between 0 and 27% (C. coronatus versus C. sazanka) of the peptide masses were found to be similar. In a study on venoms from 6 Conus species collected in the Philippines, the percentage of identical masses was between none and 9% only. The venoms from the South African Conus species antagonized the rat neuronal nicotinic acetylcholine receptors (nAChRs) α3β2, α4β2, and α7, except for C. coronatus venom that blocked the α4β2 and α7 nAChRs only. HPLC-fractionation of C. tinianus venom led to the isolation of a peptide that is active on all three receptor subtypes. It consists of 16 amino acid residues cross-linked by two disulfide bridges as revealed by de novo sequencing using tandem mass spectrometry: GGCCSHPACQNNPDYC. Posttranslational modifications include C-terminal amidation and tyrosine sulfation. The new peptide is a member of the α-conotoxin family that are competitive antagonists of nAChRs. Phylogenetic analysis of the 16S RNA from numerous Conus species has clarified the evolutionary position of endemic South African Conus species and provided the first evidence for their close genetic relationships.

  11. Interisland evolution of Trimeresurus flavoviridis venom phospholipase A(2) isozymes.

    Science.gov (United States)

    Chijiwa, Takahito; Yamaguchi, Yoko; Ogawa, Tomohisa; Deshimaru, Masanobu; Nobuhisa, Ikuo; Nakashima, Kinichi; Oda-Ueda, Naoko; Fukumaki, Yasuyuki; Hattori, Shosaku; Ohno, Motonori

    2003-03-01

    Trimeresurus flavoviridis snakes inhabit the southwestern islands of Japan. A phospholipase A(2) (PLA(2)), named PL-Y, was isolated from Okinawa T. flavoviridis venom and its amino acid sequence was determined from both protein and cDNA. PL-Y was unable to induce edema. In contrast, PLA-B, a PLA(2) from Tokunoshima T. flavoviridis venom, which is different at only three positions from PL-Y, is known to induce edema. A new PLA(2), named PLA-B', which is similar to PLA-B, was cloned from Amami-Oshima T. flavoviridis venom gland. Three T. flavoviridis venom basic [Asp(49)]PLA(2) isozymes, PL-Y (Okinawa), PLA-B (Tokunoshima), and PLA-B' (Amami-Oshima), are identical in the N-terminal half but have one to four amino acid substitutions in the beta1-sheet and its vicinity. Such interisland sequence diversities among them are due to isolation in the different environments over 1 to 2 million years and appear to have been brought about by natural selection for point mutation in their genes. Otherwise, a major PLA(2), named PLA2, ubiquitously exists in the venoms of T. flavoviridis snakes from the three islands with one to three synonymous substitutions in their cDNAs. It is assumed that the PLA2 gene is a prototype among T. flavoviridis venom PLA(2) isozyme genes and has hardly undergone nonsynonymous mutation as a principal toxic component. Phylogenetic analysis based on the amino acid sequences revealed that T. flavoviridis PLA(2) isozymes are clearly separated into three groups, PLA2 type, basic [Asp(49)]PLA(2) type, and [Lys(49)]PLA(2) type. Basic [Asp(49)]PLA(2)-type isozymes may manifest their own particular toxic functions different from those of the isozymes of the PLA2 type and [Lys(49)]PLA(2) type.

  12. Comparison of phylogeny, venom composition and neutralization by antivenom in diverse species of bothrops complex.

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    Leijiane F Sousa

    Full Text Available In Latin America, Bothrops snakes account for most snake bites in humans, and the recommended treatment is administration of multispecific Bothrops antivenom (SAB--soro antibotrópico. However, Bothrops snakes are very diverse with regard to their venom composition, which raises the issue of which venoms should be used as immunizing antigens for the production of pan-specific Bothrops antivenoms. In this study, we simultaneously compared the composition and reactivity with SAB of venoms collected from six species of snakes, distributed in pairs from three distinct phylogenetic clades: Bothrops, Bothropoides and Rhinocerophis. We also evaluated the neutralization of Bothrops atrox venom, which is the species responsible for most snake bites in the Amazon region, but not included in the immunization antigen mixture used to produce SAB. Using mass spectrometric and chromatographic approaches, we observed a lack of similarity in protein composition between the venoms from closely related snakes and a high similarity between the venoms of phylogenetically more distant snakes, suggesting little connection between taxonomic position and venom composition. P-III snake venom metalloproteinases (SVMPs are the most antigenic toxins in the venoms of snakes from the Bothrops complex, whereas class P-I SVMPs, snake venom serine proteinases and phospholipases A2 reacted with antibodies in lower levels. Low molecular size toxins, such as disintegrins and bradykinin-potentiating peptides, were poorly antigenic. Toxins from the same protein family showed antigenic cross-reactivity among venoms from different species; SAB was efficient in neutralizing the B. atrox venom major toxins. Thus, we suggest that it is possible to obtain pan-specific effective antivenoms for Bothrops envenomations through immunization with venoms from only a few species of snakes, if these venoms contain protein classes that are representative of all species to which the antivenom is

  13. Pharmacological studies of the venom of an Australian bulldog ant (Myrmecia pyriformis).

    Science.gov (United States)

    Matuszek, M A; Hodgson, W C; Sutherland, S K; King, R G

    1994-01-01

    The purpose of this study was to examine some of the pharmacological actions of venom from the Australian bulldog ant Myrmecia pyriformis. M. pyriformis venom was prepared by extraction of venom sacs in distilled water and centrifugation to remove insoluble material. Venom (2 micrograms/ml) produced a biphasic response of isolated guinea-pig ileum, i.e., an initial rapid contraction followed by a slower prolonged contraction. The histamine antagonist mepyramine (0.1 microM) inhibited the first phase of this response by approximately 80%. In the isolated rat stomach fundus strip (histamine-insensitive), venom (2-4 micrograms/ml) produced only a single contraction. Responses to venom of egg-albumin-sensitized guinea-pig ileum, were not significantly different before and after an anaphylactic response induced in vitro by egg albumin (0.5 mg/ml). Fluorometric assay showed that histamine accounted for 3.5 +/- 0.5% of the dry weight of M. pyriformis venom. Both the lipoxygenase/cyclooxygenase inhibitor BW755C and the cyclooxygenase inhibitor indomethacin significantly inhibited the response to venom of guinea-pig ileum (second phase) and rat fundus strip. M. pyriformis venom caused hemolysis of guinea pig blood. The degree of hemolysis was reduced significantly when boiled venom was used. No evidence was found that the venom contains acetylcholine, bradykinin, or 5-hydroxytryptamine or that the venom releases histamine from guinea-pig ileum. However, the results indicate that the venom contains histamine-like activity. In addition the venom was found to cause the release of cyclooxygenase products and to contain a heat-sensitive hemolytic factor.

  14. Factors contributing to amphibian road mortality in a wetland

    Institute of Scientific and Technical Information of China (English)

    Haijun GU; Qiang DAI; Qian WANG; Yuezhao WANG

    2011-01-01

    To understand road characteristics and landscape features associated with high road mortality of amphibians in Zoige Wetland National Nature Reserve,we surveyed road mortality along four major roads after rainfall in May and September 2007.Road mortality of three species,Rana kukunoris,Nanorana pleskei and Bufo minshanicus,was surveyed across 225 transects (115 in May and 110 in September).Transects were 100 m long and repeated every two kilometers along the four major roads.We used model averaging to assess factors that might determine amphibian road mortality.We recorded an average of 24.6 amphibian road mortalities per kilometer in May and 19.2 in September.Among road characteristics,road width was positively associated with road morality for R.kukunori and B.minshanicus.Traffic volume also increased the road mortality of B.minshanicus in September.Of the landscape features measured,area proportions of three types of grassland (wet,mesic and dry) within 1 km of the roads,particularly that of wet grassland,significantly increased road mortality for R.kukunori and total mortality across all three species.To most effectively reduce road mortality of amphibians in the Zoige wetlands,we suggest better road design such as avoiding wet grasslands,minimizing road width,underground passes and traffic control measures.The implementation of public transit in the area would reduce traffic volume,and hence mortality [Current Zoology 57 (6):768-774,2011].

  15. AMPHIBIAN DECLINE, ULTRAVIOLET RADIATION AND LOCAL POPULATION ADAPTATION

    Science.gov (United States)

    Amphibian population declines have been noted on both local and global scales. Causes for these declines are unknown although many hypotheses have been offered. In areas adjacent to human development, loss of habitat is a fairly well accepted cause. However in isolated, seemingl...

  16. Examining the evidence for chytridiomycosis in threatened amphibian species.

    Directory of Open Access Journals (Sweden)

    Matthew Heard

    Full Text Available Extinction risks are increasing for amphibians due to rising threats and minimal conservation efforts. Nearly one quarter of all threatened/extinct amphibians in the IUCN Red List is purportedly at risk from the disease chytridiomycosis. However, a closer look at the data reveals that Batrachochytrium dendrobatidis (the causal agent has been identified and confirmed to cause clinical disease in only 14% of these species. Primary literature surveys confirm these findings; ruling out major discrepancies between Red List assessments and real-time science. Despite widespread interest in chytridiomycosis, little progress has been made between assessment years to acquire evidence for the role of chytridiomycosis in species-specific amphibian declines. Instead, assessment teams invoke the precautionary principle when listing chytridiomycosis as a threat. Precaution is valuable when dealing with the world's most threatened taxa, however scientific research is needed to distinguish between real and predicted threats in order to better prioritize conservation efforts. Fast paced, cost effective, in situ research to confirm or rule out chytridiomycosis in species currently hypothesized to be threatened by the disease would be a step in the right direction. Ultimately, determining the manner in which amphibian conservation resources are utilized is a conversation for the greater conservation community that we hope to stimulate here.

  17. Effects of terrestrial buffer zones on amphibians on golf courses.

    Directory of Open Access Journals (Sweden)

    Holly J Puglis

    Full Text Available A major cause of amphibian declines worldwide is habitat destruction or alteration. Public green spaces, such as golf courses and parks, could serve as safe havens to curb the effects of habitat loss if managed in ways to bolster local amphibian communities. We reared larval Blanchard's cricket frogs (Acris blanchardi and green frogs (Rana clamitans in golf course ponds with and without 1 m terrestrial buffer zones, and released marked cricket frog metamorphs at the golf course ponds they were reared in. Larval survival of both species was affected by the presence of a buffer zone, with increased survival for cricket frogs and decreased survival for green frogs when reared in ponds with buffer zones. No marked cricket frog juveniles were recovered at any golf course pond in the following year, suggesting that most animals died or migrated. In a separate study, we released cricket frogs in a terrestrial pen and allowed them to choose between mown and unmown grass. Cricket frogs had a greater probability of using unmown versus mown grass. Our results suggest that incorporating buffer zones around ponds can offer suitable habitat for some amphibian species and can improve the quality of the aquatic environment for some sensitive local amphibians.

  18. ESTIMATION OF UV-B EXPOSURE IN AMPHIBIAN AQUATIC ENVIRONMENTS

    Science.gov (United States)

    Estimation of ultraviolet radiation B (UV-B; 280 to 320 nm wavelenghts) dose is essential for determining whether UV-B contributes to amphibian population declines and malformations. UV-B dose in wetlands is effected by location, time of day and year, atmospheric levels of ozone,...

  19. Measuring the meltdown: drivers of global amphibian extinction and decline.

    Directory of Open Access Journals (Sweden)

    Navjot S Sodhi

    Full Text Available Habitat loss, climate change, over-exploitation, disease and other factors have been hypothesised in the global decline of amphibian biodiversity. However, the relative importance of and synergies among different drivers are still poorly understood. We present the largest global analysis of roughly 45% of known amphibians (2,583 species to quantify the influences of life history, climate, human density and habitat loss on declines and extinction risk. Multi-model Bayesian inference reveals that large amphibian species with small geographic range and pronounced seasonality in temperature and precipitation are most likely to be Red-Listed by IUCN. Elevated habitat loss and human densities are also correlated with high threat risk. Range size, habitat loss and more extreme seasonality in precipitation contributed to decline risk in the 2,454 species that declined between 1980 and 2004, compared to species that were stable (n = 1,545 or had increased (n = 28. These empirical results show that amphibian species with restricted ranges should be urgently targeted for conservation.

  20. Effects of terrestrial buffer zones on amphibians on golf courses.

    Science.gov (United States)

    Puglis, Holly J; Boone, Michelle D

    2012-01-01

    A major cause of amphibian declines worldwide is habitat destruction or alteration. Public green spaces, such as golf courses and parks, could serve as safe havens to curb the effects of habitat loss if managed in ways to bolster local amphibian communities. We reared larval Blanchard's cricket frogs (Acris blanchardi) and green frogs (Rana clamitans) in golf course ponds with and without 1 m terrestrial buffer zones, and released marked cricket frog metamorphs at the golf course ponds they were reared in. Larval survival of both species was affected by the presence of a buffer zone, with increased survival for cricket frogs and decreased survival for green frogs when reared in ponds with buffer zones. No marked cricket frog juveniles were recovered at any golf course pond in the following year, suggesting that most animals died or migrated. In a separate study, we released cricket frogs in a terrestrial pen and allowed them to choose between mown and unmown grass. Cricket frogs had a greater probability of using unmown versus mown grass. Our results suggest that incorporating buffer zones around ponds can offer suitable habitat for some amphibian species and can improve the quality of the aquatic environment for some sensitive local amphibians.

  1. Expanding Distribution of Lethal Amphibian Fungus Batrachochytrium salamandrivorans in Europe.

    Science.gov (United States)

    Spitzen-van der Sluijs, Annemarieke; Martel, An; Asselberghs, Johan; Bales, Emma K; Beukema, Wouter; Bletz, Molly C; Dalbeck, Lutz; Goverse, Edo; Kerres, Alexander; Kinet, Thierry; Kirst, Kai; Laudelout, Arnaud; Marin da Fonte, Luis F; Nöllert, Andreas; Ohlhoff, Dagmar; Sabino-Pinto, Joana; Schmidt, Benedikt R; Speybroeck, Jeroen; Spikmans, Frank; Steinfartz, Sebastian; Veith, Michael; Vences, Miguel; Wagner, Norman; Pasmans, Frank; Lötters, Stefan

    2016-07-01

    Emerging fungal diseases can drive amphibian species to local extinction. During 2010-2016, we examined 1,921 urodeles in 3 European countries. Presence of the chytrid fungus Batrachochytrium salamandrivorans at new locations and in urodeles of different species expands the known geographic and host range of the fungus and underpins its imminent threat to biodiversity.

  2. Glyphosate applications on arable fields considerably coincide with migrating amphibians.

    Science.gov (United States)

    Berger, Gert; Graef, Frieder; Pfeffer, Holger

    2013-01-01

    Glyphosate usage is increasing worldwide and the application schemes of this herbicide are currently changing. Amphibians migrating through arable fields may be harmed by Glyphosate applied to field crops. We investigated the population-based temporal coincidence of four amphibian species with Glyphosate from 2006 to 2008. Depending on a) age- and species-specific main migration periods, b) crop species, c) Glyphosate application mode for crops, and d) the presumed DT50 value (12 days or 47 days) of Glyphosate, we calculated up to 100% coincidence with Glyphosate. The amphibians regularly co-occur with pre-sowing/pre-emerging Glyphosate applications to maize in spring and with stubble management prior to crop sowing in late summer and autumn. Siccation treatment in summer coincides only with early pond-leaving juveniles. We suggest in-depth investigations of both acute and long-term effects of Glyphosate applications on amphibian populations not only focussed on exposure during aquatic periods but also terrestrial life stages.

  3. Using Reptile and Amphibian Activities in the Classroom

    Science.gov (United States)

    Tomasek, Terry; Matthews, Catherine E.

    2008-01-01

    Reptiles and amphibians are a diverse and interesting group of organisms. The four activities described in this article take students' curiosity into the realm of scientific understanding. The activities involve the concepts of species identification; animal adaptations, communication, and habitat; and conservation. (Contains 1 table and 2…

  4. Preliminary checklist of amphibians and reptiles from Baramita, Guyana

    Science.gov (United States)

    Reynolds, R.P.; MacCulloch, R.D.

    2012-01-01

    We provide an initial checklist of the herpetofauna of Baramita, a lowland rainforest site in the Northwest Region of Guyana. Twenty-five amphibian and 28 reptile species were collected during two separate dry-season visits. New country records for two species of snakes are documented, contributing to the knowledge on the incompletely known herpetofauna of Guyana.

  5. Emerging contaminants and their potential effects on amphibians and reptiles

    Science.gov (United States)

    Serious threats to the health and sustainability of global amphibian populations have been well documented over the last few decades. Encroachment upon and destruction of primary habitat is the most critical threat, but some species have disappeared while their habitat remains. Additional stressor...

  6. Batrachochytrium salamandrivorans sp. nov. causes lethal chytridiomycosis in amphibians.

    Science.gov (United States)

    Martel, An; Spitzen-van der Sluijs, Annemarieke; Blooi, Mark; Bert, Wim; Ducatelle, Richard; Fisher, Matthew C; Woeltjes, Antonius; Bosman, Wilbert; Chiers, Koen; Bossuyt, Franky; Pasmans, Frank

    2013-09-17

    The current biodiversity crisis encompasses a sixth mass extinction event affecting the entire class of amphibians. The infectious disease chytridiomycosis is considered one of the major drivers of global amphibian population decline and extinction and is thought to be caused by a single species of aquatic fungus, Batrachochytrium dendrobatidis. However, several amphibian population declines remain unexplained, among them a steep decrease in fire salamander populations (Salamandra salamandra) that has brought this species to the edge of local extinction. Here we isolated and characterized a unique chytrid fungus, Batrachochytrium salamandrivorans sp. nov., from this salamander population. This chytrid causes erosive skin disease and rapid mortality in experimentally infected fire salamanders and was present in skin lesions of salamanders found dead during the decline event. Together with the closely related B. dendrobatidis, this taxon forms a well-supported chytridiomycete clade, adapted to vertebrate hosts and highly pathogenic to amphibians. However, the lower thermal growth preference of B. salamandrivorans, compared with B. dendrobatidis, and resistance of midwife toads (Alytes obstetricans) to experimental infection with B. salamandrivorans suggest differential niche occupation of the two chytrid fungi.

  7. On the worrying fate of Data Deficient amphibians.

    Science.gov (United States)

    Nori, Javier; Loyola, Rafael

    2015-01-01

    The 'Data Deficient' (DD) category of the IUCN Red List assembles species that cannot be placed in another category due to insufficient information. This process generates uncertainty about whether these species are safe or actually in danger. Here, we give a global overview on the current situation of DD amphibian species (almost a quarter of living amphibians) considering land-use change through habitat modification, the degree of protection of each species and the socio-political context of each country harboring DD species. We found that DD amphibians have, on average, 81% of their ranges totally outside protected areas. Worryingly, more than half of DD species have less than 1% of their distribution represented in protected areas. Furthermore, the percentage of overlap between species' range and human-modified landscapes is high, at approximately 58%. Many countries harboring a large number of DD species show a worrying socio-political trend illustrated by substantial, recent incremental increases in the Human Development Index and lower incremental increases in the establishment of protected areas. Most of these are African countries, which are located mainly in the central and southern regions of the continent. Other countries with similar socio-political trends are in southeastern Asia, Central America, and in the northern region of South America. This situation is concerning, but it also creates a huge opportunity for considering DD amphibians in future conservation assessments, planning, and policy at different levels of government administration.

  8. Preliminary amphibian surveys : Baca National Wildlife Refuge : July & August, 2015

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes an initial amphibian survey effort on the Baca National Wildlife Refuge, conducted on 7/17/15, 7/24/15, and 8/28/15. The main emphasis of this...

  9. Toxicity of road salt to Nova Scotia amphibians

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Sara J. [Department of Biology, Saint Mary' s University, 923 Robie Street, Halifax, NS, B3H 3C3 (Canada); Russell, Ronald W. [Department of Biology, Saint Mary' s University, 923 Robie Street, Halifax, NS, B3H 3C3 (Canada)], E-mail: ron.russell@smu.ca

    2009-01-15

    The deposition of chemical pollutants into roadside wetlands from runoff is a current environmental concern. In northern latitudes, a major pollutant in runoff water is salt (NaCl), used as de-icing agents. In this study, 26 roadside ponds were surveyed for amphibian species richness and chloride concentration. Acute toxicity tests (LC{sub 50}) were performed on five locally common amphibian species using a range of environmentally significant NaCl concentrations. Field surveys indicated that spotted salamanders (Ambystoma maculatum) and wood frogs (Rana sylvatica) did not occupy high chloride ponds. American toads (Bufo americanus) showed no pond preference based on chloride concentration. Acute toxicity tests showed spotted salamanders and wood frogs were most sensitive to chloride, and American toads were the least. Spring peepers (Pseudacris crucifer) and green frogs (Rana clamitans) showed intermediate sensitivities. We concluded that chloride concentrations in ponds due to application of de-icing salts, influenced community structure by excluding salt intolerant species. - Salt toxicity is presented as a mechanism affecting the distribution of amphibians and structure of amphibian communities in roadside wetlands.

  10. Can myxosporean parasites compromise fish and amphibian reproduction?

    Science.gov (United States)

    Sitjà-Bobadilla, Ariadna

    2009-08-22

    Research into fish and amphibian reproduction has increased exponentially in recent years owing to the expansion of the aquaculture industry, the need to recover fishery populations, the impact of endocrine disruptors on the aquatic environment and the global decline of amphibian populations. This review focuses on a group of parasites, the Myxozoa, that affect fish and amphibian reproduction. Lists of the myxosporeans that specifically infect gonads are provided. Most of these are parasitic of freshwater hosts, and most amphibian cases are reported from testes. Sex specificity and sex reversal are discussed in relation to gonadal parasitism. The immune response of the fish to the infection is described, and the contribution of the immunoprivilege of gonads to host invasion is emphasized. The pathological effect of these parasites can be significant, especially in aquacultured broodstocks, on some occasions, leading to parasitic castration. Although myxosporean parasites are currently not very frequent in gonads, their impact could increase in the future owing to the transactions in the global market. Their easy release into the aquatic environment with spawning could make their spreading even more feasible. In the absence of commercial drugs or vaccines to treat and prevent these infections, there is an urgent need to develop specific, rapid and reliable diagnostic tools to control and manage animal movements. In addition, much effort is still to be made on deciphering the life cycle of these organisms, their invasion strategies and their immune evasion mechanisms.

  11. Rayleigh instability of the inverted one-cell amphibian embryo

    NARCIS (Netherlands)

    Nouri, Comron; Luppes, Roel; Veldman, Arthur E.P.; Tuszynski, Jack A.; Gordon, Richard

    2008-01-01

    The one-cell amphibian embryo is modeled as a rigid spherical shell containing equal volumes of two immiscible fluids with different densities and viscosities and a surface tension between them. The fluids represent denser yolk in the bottom hemisphere and clearer cytoplasm and the germinal vesicle

  12. Salmonella Infections Caused by Reptiles and Amphibians in Childcare Centers

    Centers for Disease Control (CDC) Podcasts

    2013-02-07

    Dr. Neil Vora, an EIS Officer at CDC, discusses his article about Salmonella infections in childcare centers caused by reptiles and amphibians.  Created: 2/7/2013 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 2/7/2013.

  13. Animal venoms/toxins and the complement system.

    Science.gov (United States)

    Tambourgi, Denise V; van den Berg, Carmen W

    2014-10-01

    Nature is a wealthy source of agents that have been shown to be beneficial to human health, but nature is also a rich source of potential dangerous health damaging compounds. This review will summarise and discuss the agents from the animal kingdom that have been shown to interact with the human complement (C) system. Most of these agents are toxins found in animal venoms and animal secretions. In addition to the mechanism of action of these toxins, their contribution to the field of complement, their role in human pathology and the potential benefit to the venomous animal itself will be discussed. Potential therapeutic applications will also be discussed.

  14. A study of bacterial contamination of rattlesnake venom

    Directory of Open Access Journals (Sweden)

    E. Garcia-Lima

    1987-03-01

    Full Text Available The authors studied the bacterial contamination of rattlesnake venom isolated from snakes in captivity and wild snakes caught recently. The captive snakes showed a relatively high incidence of bacterial contamination of their venom.Os autores estudaram a contaminação bacteriana do veneno dë cascavéis mantidas em cativeiro e das recentemente capturadas. Verificaram que os venenos dos animais cativos apresentaram alta incidência de contaminação e os tidos como recentemente capturados estavam com baixa contaminação aparente.

  15. Biodistribution studies of bee venom and spider toxin using radiotracers

    Directory of Open Access Journals (Sweden)

    C. M. Yonamine

    2005-03-01

    Full Text Available The use of radiotracers allows the understanding of the bioavailability process, biodistribution, and kinetics of any molecule labelled with an isotope, which does not alter the molecule's biological properties. In this work, technetium-99m and iodine-125 were chosen as radiotracers for biodistribution studies in mice using bee (Apis mellifera venom and a toxin (PnTX2-6 from the Brazilian "armed" spider (Phoneutria nigriventer venom. Incorporated radioactivity was measured in the blood, brain, heart, lung, liver, kidney, adrenal gland, spleen, stomach, testicle, intestine, muscle, and thyroid gland. Results provided the blood kinetic parameter, and different organs distribution rates.

  16. Autonomic effects of some scorpion venoms and toxins.

    Science.gov (United States)

    Gwee, Matthew C E; Nirthanan, Selvanayagam; Khoo, Hoon-Eng; Gopalakrishnakone, Ponnampalam; Kini, R Manjunatha; Cheah, Li-Sam

    2002-09-01

    1. The autonomic effects of venoms and toxins from several species of scorpions, including the Indian red scorpion Mesobuthus tamulus, the Chinese scorpion Buthus martensi Karsch and the Israeli scorpion Leiurus quinquestriatus quinquestriatus, all belonging to Buthidae, and the Asian black scorpions Heterometrus longimanus and Heterometrus spinifer, belonging to Scorpionidae, are reviewed. 2. The effects of the venoms of M. tamulus and L. q. quinquestriatus on noradrenergic and nitrergic transmission in the rat isolated anococcygeus muscle revealed that both venoms mediated their pharmacological effects via a prejunctional mechanism involving the activation of voltage-sensitive sodium channels with consequent release of neurotransmitters that mediate target organ responses, similar to the effects mediated by other alpha-scorpion toxins. 3. Two new toxins, Makatoxin I and Bukatoxin, were purified to homogeneity from the venom of B. martensi Karsch. Determination of their complete amino acid sequences confirmed that both toxins belonged to the class of alpha-scorpion toxins. The effects of both toxins on noradrenergic and nitrergic transmission in the rat anococcygeus muscle provided firm evidence that their pharmacological actions also closely resembled those mediated by other alpha-scorpion toxins on neuronal voltage-sensitive sodium channels. 4. The venoms of H. longimanus and H. spinifer were found to have high concentrations of noradrenaline (1.8 +/- 0.3 mmol/L) and relatively high concentrations of acetylcholine (79.8 +/- 1.7 micromol/L) together with noradrenaline (146.7 +/- 19.8 micromol/L), respectively, which can account for their potent direct cholinergic and noradrenergic agonist actions in the rat anococcygeus muscle. 5. Our studies confirmed that the rat anococcygeus muscle is an excellent nerve-smooth muscle preparation for investigating the effects of bioactive agents on noradrenergic and nitrergic transmission, as well as the direct agonist actions

  17. Bioactive Mimetics of Conotoxins and other Venom Peptides

    Directory of Open Access Journals (Sweden)

    Peter J. Duggan

    2015-10-01

    Full Text Available Ziconotide (Prialt®, a synthetic version of the peptide ω-conotoxin MVIIA found in the venom of a fish-hunting marine cone snail Conus magnus, is one of very few drugs effective in the treatment of intractable chronic pain. However, its intrathecal mode of delivery and narrow therapeutic window cause complications for patients. This review will summarize progress in the development of small molecule, non-peptidic mimics of Conotoxins and a small number of other venom peptides. This will include a description of how some of the initially designed mimics have been modified to improve their drug-like properties.

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

    Directory of Open Access Journals (Sweden)

    Timothy N. W. Jackson

    2013-12-01

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

  19. Spatial Biodiversity Patterns of Madagascar's Amphibians and Reptiles.

    Science.gov (United States)

    Brown, Jason L; Sillero, Neftali; Glaw, Frank; Bora, Parfait; Vieites, David R; Vences, Miguel

    2016-01-01

    Madagascar has become a model region for testing hypotheses of species diversification and biogeography, and many studies have focused on its diverse and highly endemic herpetofauna. Here we combine species distribution models of a near-complete set of species of reptiles and amphibians known from the island with body size data and a tabulation of herpetofaunal communities from field surveys, compiled up to 2008. Though taxonomic revisions and novel distributional records arose since compilation, we are confident that the data are appropriate for inferring and comparing biogeographic patterns among these groups of organisms. We observed species richness of both amphibians and reptiles was highest in the humid rainforest biome of eastern Madagascar, but reptiles also show areas of high richness in the dry and subarid western biomes. In several amphibian subclades, especially within the Mantellidae, species richness peaks in the central eastern geographic regions while in reptiles different subclades differ distinctly in their richness centers. A high proportion of clades and subclades of both amphibians and reptiles have a peak of local endemism in the topographically and bioclimatically diverse northern geographic regions. This northern area is roughly delimited by a diagonal spanning from 15.5°S on the east coast to ca. 15.0°S on the west coast. Amphibian diversity is highest at altitudes between 800-1200 m above sea-level whereas reptiles have their highest richness at low elevations, probably reflecting the comparatively large number of species specialized to the extended low-elevation areas in the dry and subarid biomes. We found that the range sizes of both amphibians and reptiles strongly correlated with body size, and differences between the two groups are explained by the larger body sizes of reptiles. However, snakes have larger range sizes than lizards which cannot be readily explained by their larger body sizes alone. Range filling, i.e., the amount of

  20. Spatial Biodiversity Patterns of Madagascar's Amphibians and Reptiles.

    Directory of Open Access Journals (Sweden)

    Jason L Brown

    Full Text Available Madagascar has become a model region for testing hypotheses of species diversification and biogeography, and many studies have focused on its diverse and highly endemic herpetofauna. Here we combine species distribution models of a near-complete set of species of reptiles and amphibians known from the island with body size data and a tabulation of herpetofaunal communities from field surveys, compiled up to 2008. Though taxonomic revisions and novel distributional records arose since compilation, we are confident that the data are appropriate for inferring and comparing biogeographic patterns among these groups of organisms. We observed species richness of both amphibians and reptiles was highest in the humid rainforest biome of eastern Madagascar, but reptiles also show areas of high richness in the dry and subarid western biomes. In several amphibian subclades, especially within the Mantellidae, species richness peaks in the central eastern geographic regions while in reptiles different subclades differ distinctly in their richness centers. A high proportion of clades and subclades of both amphibians and reptiles have a peak of local endemism in the topographically and bioclimatically diverse northern geographic regions. This northern area is roughly delimited by a diagonal spanning from 15.5°S on the east coast to ca. 15.0°S on the west coast. Amphibian diversity is highest at altitudes between 800-1200 m above sea-level whereas reptiles have their highest richness at low elevations, probably reflecting the comparatively large number of species specialized to the extended low-elevation areas in the dry and subarid biomes. We found that the range sizes of both amphibians and reptiles strongly correlated with body size, and differences between the two groups are explained by the larger body sizes of reptiles. However, snakes have larger range sizes than lizards which cannot be readily explained by their larger body sizes alone. Range filling

  1. Bioaccumulation and maternal transfer of mercury and selenium in amphibians.

    Science.gov (United States)

    Bergeron, Christine M; Bodinof, Catherine M; Unrine, Jason M; Hopkins, William A

    2010-04-01

    Amphibian population declines have been documented worldwide and environmental contaminants are believed to contribute to some declines. Maternal transfer of bioaccumulated contaminants to offspring may be an important and overlooked mechanism of impaired reproductive success that affects amphibian populations. Mercury (Hg) is of particular concern due to its ubiquity in the environment, known toxicity to other wildlife, and complex relationships with other elements, such as selenium (Se). The objectives of the present study were to describe the relationships between total Hg (THg), methlymercury (MMHg), and Se in three amphibian species (Plethodon cinereus, Eurycea bislineata cirrigera, and Bufo americanus) along a Hg-polluted river and floodplain, and to determine if B. americanus maternally transfers Hg and Se to its eggs in a tissue residue-dependent manner. Total Hg and MMHg concentrations in all species spanned two orders of magnitude between the reference and contaminated areas, while Se concentrations were generally low in all species at both sites. Strong positive relationships between THg and MMHg in tissues of all species were observed throughout. Both Hg and Se were maternally transferred from females to eggs in B. americanus, but the percentage of the females' Hg body burden transferred to eggs was low compared with Se. In addition, Hg concentrations appeared to positively influence the amount of Se transferred from female to eggs. The present study is the first to confirm a correlation between Hg concentrations in female carcass and eggs in amphibians and among the first to describe co-transference of Se and Hg in an anamniotic vertebrate. The results suggest future work is needed to determine whether maternal transfer of Hg has transgenerational implications for amphibian progeny.

  2. Projected climate impacts for the amphibians of the western hemisphere

    Science.gov (United States)

    Lawler, Joshua J.; Shafer, Sarah L.; Bancroft, Betsy A.; Blaustein, Andrew R.

    2010-01-01

    Given their physiological requirements, limited dispersal abilities, and hydrologically sensitive habitats, amphibians are likely to be highly sensitive to future climatic changes. We used three approaches to map areas in the western hemisphere where amphibians are particularly likely to be affected by climate change. First, we used bioclimatic models to project potential climate-driven shifts in the distribution of 413 amphibian species based on 20 climate simulations for 2071–2100. We summarized these projections to produce estimates of species turnover. Second, we mapped the distribution of 1099 species with restricted geographic ranges. Finally, using the 20 future climate-change simulations, we mapped areas that were consistently projected to receive less seasonal precipitation in the coming century and thus were likely to have altered microclimates and local hydrologies. Species turnover was projected to be highest in the Andes Mountains and parts of Central America and Mexico, where, on average, turnover rates exceeded 60% under the lower of two emissions scenarios. Many of the restricted-range species not included in our range-shift analyses were concentrated in parts of the Andes and Central America and in Brazil's Atlantic Forest. Much of Central America, southwestern North America, and parts of South America were consistently projected to experience decreased precipitation by the end of the century. Combining the results of the three analyses highlighted several areas in which amphibians are likely to be significantly affected by climate change for multiple reasons. Portions of southern Central America were simultaneously projected to experience high species turnover, have many additional restricted-range species, and were consistently projected to receive less precipitation. Together, our three analyses form one potential assessment of the geographic vulnerability of amphibians to climate change and as such provide broad-scale guidance for directing

  3. Determining with SEM, structure of the venom apparatus in the tube web spider, Segestria florentina (Araneae: Segestriidae

    Directory of Open Access Journals (Sweden)

    Suna Cebesoy

    2013-08-01

    Full Text Available The objective of the present study was to describe functional morphological features of venom apparatus in the tube web spider, Segestria florentina (Rossi, 1790 (Araneae: Segestriidae by using scanning electron microscope (SEM. The venom apparatus is situated in the anterior part of the prosoma, and is composed of a pair of venom glands and chelicerae. The chelicera of S. florentina has two parts: basal segment and a movable articulated apical segment (fang. The cheliceral fang rests in a groove on the basal segment of chelicerae. A venom hole is located on the subterminal part of each fang. A pair of venom glands is completely separate but similar to each other within the prosoma. Each venom gland is surrounded by striated muscle bundles, such as with the capsules. The venom, produced in the venom glands, is carried by venom ducts passing throughout the chelicerae. Each venom gland has its own venom duct, chelicera and fang. The venom is excreted from the venom pore on the subterminal part of the fang by means of muscular contractions covering the venom gland.

  4. Survival of the amphibian chytrid fungus Batrachochytrium dendrobatidis on bare hands and gloves: hygiene implications for amphibian handling.

    Science.gov (United States)

    Mendez, Diana; Webb, Rebecca; Berger, Lee; Speare, Rick

    2008-11-20

    Hygiene protocols for handling amphibians in the field and in laboratories have been proposed to decrease the transmission of chytridiomycosis caused by infection with the amphibian chytrid fungus Batrachochytrium dendrobatidis, which is responsible for global amphibian declines. However, these protocols are mainly based on theoretical principles. The aim of this study was to develop an evidence-based approach to amphibian handling hygiene protocols by testing the survival of B. dendrobatidis on human hands and various gloves. Bare or gloved human fingers were exposed to cultured zoospores and zoosporangia of B. dendrobatidis. Survival of B. dendrobatidis on hands and gloves was tested for up to 10 min post-exposure by inoculation onto tryptone/gelatin hydrolysate/lactose (TGhL) agar plates. The effects of repeated hand washings with water and with 70% ethanol and of washing gloves with water were also tested. Bare human skin demonstrated a fungicidal effect on B. dendrobatidis by 2 min and killed 100% of cells by 6 min, but this killing effect was reduced by repeated washing with water and ethanol. Nitrile gloves killed all B. dendrobatidis on contact, but washing in water decreased this effect. Latex and polyethylene gloves had no killing effect, and B. dendrobatidis survived for over 6 min. The killing effect of vinyl gloves varied with brands and batches. These results support the use of an unused pair of gloves for each new amphibian handled in either the field or the laboratory, and if this is not possible, bare hands are a preferable, although imperfect, alternative to continual use of the same pair of gloves.

  5. Restriction and recruitment-gene duplication and the origin and evolution of snake venom toxins.

    Science.gov (United States)

    Hargreaves, Adam D; Swain, Martin T; Hegarty, Matthew J; Logan, Darren W; Mulley, John F

    2014-08-01

    Snake venom has been hypothesized to have originated and diversified through a process that involves duplication of genes encoding body proteins with subsequent recruitment of the copy to the venom gland, where natural selection acts to develop or increase toxicity. However, gene duplication is known to be a rare event in vertebrate genomes, and the recruitment of duplicated genes to a novel expression domain (neofunctionalization) is an even rarer process that requires the evolution of novel combinations of transcription factor binding sites in upstream regulatory regions. Therefore, although this hypothesis concerning the evolution of snake venom is very unlikely and should be regarded with caution, it is nonetheless often assumed to be established fact, hindering research into the true origins of snake venom toxins. To critically evaluate this hypothesis, we have generated transcriptomic data for body tissues and salivary and venom glands from five species of venomous and nonvenomous reptiles. Our comparative transcriptomic analysis of these data reveals that snake venom does not evolve through the hypothesized process of duplication and recruitment of genes encoding body proteins. Indeed, our results show that many proposed venom toxins are in fact expressed in a wide variety of body tissues, including the salivary gland of nonvenomous reptiles and that these genes have therefore been restricted to the venom gland following duplication, not recruited. Thus, snake venom evolves through the duplication and subfunctionalization of genes encoding existing salivary proteins. These results highlight the danger of the elegant and intuitive "just-so story" in evolutionary biology.

  6. Coral snake venoms: mode of action and pathophysiology of experimental envenomation

    Directory of Open Access Journals (Sweden)

    Oswald Vital Brazil

    1987-06-01

    Full Text Available Coral snakes, the New World Elapidae, are included in the genera Micniroides and Micrurus. The genus Mlcrurus comprises nearly all coral snake species and those which are responsible for human snake-bite accidents. The following generalizations concerning the effects induced by their venoms, and their venom-properties can be made. Coral snake venoms are neurotoxic, producing loss of muscle strenght and death by respiratory paralysis. Local edema and necrosis are not induced nor blood coagulation or hemorrhages. Proteolysis activity is absent or of very low grade. They display phospholipase A2 activity. Nephrotoxic effects are not evoked. The main toxins from elapid venoms are postsynaptic and presynaptic neurotoxins and cardiotoxins. Phospholipases A2 endowed with myonecrotic or cardiotoxin-like properties are important toxic components from some elapid venoms. The mode of action of Micrurus frontalis, M. lemniscatus, M. corallinus and M. fulvius venoms has been investigated in isolated muscle preparations and is here discussed. It is shown that while M. frontalis and M. lemniscatus venoms must contain only neurotoxins that act at the cholinergic end-plate receptor (postsynaptic neurotoxins, M. corallinus venom also inhibits evoked acetylcholine release by the motor nerve endings (presynaptic neurotoxin-like effect and M. fulvius induces muscle fiber membrane depolarization (cardiotoxin-like effect. The effects produced by M. corallinus and M. fulvius venoms in vivo in dogs and M. frontalis venom in dogs and monkeys are also reported.

  7. The in vivo cardiovascular effects of an Australasian box jellyfish (Chiropsalmus sp.) venom in rats.

    Science.gov (United States)

    Ramasamy, Sharmaine; Isbister, Geoffrey K; Seymour, Jamie E; Hodgson, Wayne C

    2005-03-01

    Using a new technique to extract venom from the nematocysts of jellyfish, the in vivo cardiovascular effects of Chiropsalmus sp. venom were investigated in anaesthetized rats. Chiropsalmus sp. venom (150 microg/kg, i.v.) produced a transient hypertensive response (44+/-4 mmHg; n=6) followed by hypotension and cardiovascular collapse. Concurrent artificial respiration or pretreatment with Chironex fleckeri antivenom (AV, 3000 U/kg, i.v.) did not have any effect on the venom-induced hypertensive response nor the subsequent cardiovascular collapse. The cardiovascular response of animals receiving venom after the infusion of MgSO4 (50-70 mM @ 0.25 ml/min, i.v.; n=5) alone, or in combination with AV (n=5), was not significantly different from rats receiving venom alone. Prior administration of prazosin (50 microg/kg, i.v.; n=4) or ketanserin (1 mg/kg, i.v.; n=4) did not significantly attenuate the hypertensive response nor prevent the cardiovascular collapse induced by venom (50 microg/kg, i.v.). In contrast to previous work examining C. fleckeri venom, administration of AV alone, or in combination with MgSO4, was not effective in preventing cardiovascular collapse following the administration of Chiropsalmus sp. venom. This indicates that the venom of the two related box jellyfish contain different lethal components and highlights the importance of species identification prior to initiating treatment regimes following jellyfish envenoming.

  8. Antivenom to the venom of the male Sydney funnel-web spider Atrax robustus: preliminary report.

    Science.gov (United States)

    Sutherland, S K

    1980-10-18

    A purified rabbit IgG (antivenom) has been isolated from rabbits immunized with male Atrax robustus venom. This preparation has been shown to neutralize in vitro, male venom in a ratio of 97 microgram of IgG to 1 microgram of male venom. The venoms of a number of other members of the Atrax genus are also neutralized in vitro by this antivenom. Of particular importance is the fact that the venom of the extremely dangerous female A. formidabilis is neutralized. A serum harvest of 55 mL from an immunized rabbit yielded a total of 1.1869 g of immune IgG using the Protein A-Sepharose procedure. This quantity is sufficient antivenom to neutralize in vitro the average yield of 67 spiders. These findings suggest the preparation of an antivenom for human use is now feasible. The antivenom was shown to effectively neutralize venom in monkeys either when it was premixed with the venom before injection or when it was injected separately 10 minutes after injection of venom. This is the first time in-vitro and in-vivo neutralization of this venom has been demonstrated in the monkey. In other studies, a range of non-immunized animal sera was shown to have no inherent ability to neutralize male A. robustus venom in vitro.

  9. Effect of gamma irradiation on toxicity and immunogenicity of Androctonus australis hector venom

    Energy Technology Data Exchange (ETDEWEB)

    Abib, L. [Univ. des Sciences et de la Technologie, Lab. de Biologie Cellulaire et Moleculaire, Faculte des Sciences Biologiques, Houari Boumedienne, Bab Ezzouar (Algeria); Laraba-Djebari, F. [Univ. des Sciences et de la Technologie, Lab. de Biologie Cellulaire et Moleculaire, Faculte des Sciences Biologiques, Houari Boumedienne, Bab Ezzouar, Alger (Algeria); Institut Pasteur d' Algerie, Lab. de Recherche et de Developpement sur les Venins, Alger (Algeria); E-mail: flaraba@ibnsina.ands.dz

    2003-12-01

    An investigation was made of the radiosensitivity of the toxic and immunological properties of Androctonus australis hector venom. This venom was irradiated with two doses of gamma rays (1 and 2 kGy) from a {sup 60}Co source. The results showed that venom toxicity was abolished for the two radiation doses (1 and 2 kGy) with, respectively, 10 and 25 times its initial LD50 value. However, irradiated venoms were immunogenic, and the antibodies elicited by them were able to recognize the native venom by enzyme-linked immunosorbent assay. Antisera raised against these toxoids (1 and 2 kGy) had a higher neutralizing capacity and immunoreactivity against all components of native venom than did the antiserum produced against the native venom. The antiserum of rabbits immunized with 2-kGy-irradiated venom was more efficient than 1-kGy-irradiated toxoid antiserum. Indeed, in vivo protection assays showed that the mice immunized with 2-kGy-irradiated venom resisted lethal doses (i.p.) of A. australis hector venom. (author)

  10. Recruitment and diversification of an ecdysozoan family of neuropeptide hormones for black widow spider venom expression.

    Science.gov (United States)

    McCowan, Caryn; Garb, Jessica E

    2014-02-25

    Venoms have attracted enormous attention because of their potent physiological effects and dynamic evolution, including the convergent recruitment of homologous genes for venom expression. Here we provide novel evidence for the recruitment of genes from the Crustacean Hyperglycemic Hormone (CHH) and arthropod Ion Transport Peptide (ITP) superfamily for venom expression in black widow spiders. We characterized latrodectin peptides from venom gland cDNAs from the Western black widow spider (Latrodectus hesperus), the brown widow (Latrodectus geometricus) and cupboard spider (Steatoda grossa). Phylogenetic analyses of these sequences with homologs from other spider, scorpion and wasp venom cDNAs, as well as CHH/ITP neuropeptides, show latrodectins as derived members of the CHH/ITP superfamily. These analyses suggest that CHH/ITP homologs are more widespread in spider venoms, and were recruited for venom expression in two additional arthropod lineages. We also found that the latrodectin 2 gene and nearly all CHH/ITP genes include a phase 2 intron in the same position, supporting latrodectin's placement within the CHH/ITP superfamily. Evolutionary analyses of latrodectins suggest episodes of positive selection along some sequence lineages, and positive and purifying selection on specific codons, supporting its functional importance in widow venom. We consider how this improved understanding of latrodectin evolution informs functional hypotheses regarding its role in black widow venom as well as its potential convergent recruitment for venom expression across arthropods.

  11. ADP is a vasodilator component from Lasiodora sp. mygalomorph spider venom.

    Science.gov (United States)

    Horta, C C; Rezende, B A; Oliveira-Mendes, B B R; Carmo, A O; Capettini, L S A; Silva, J F; Gomes, M T; Chávez-Olórtegui, C; Bravo, C E S; Lemos, V S; Kalapothakis, E

    2013-09-01

    Members of the spider genus Lasiodora are widely distributed in Brazil, where they are commonly known as caranguejeiras. Lasiodora spider venom is slightly harmful to humans. The bite of this spider causes local pain, edema and erythema. However, Lasiodora sp. spider venom may be a source of important pharmacological tools. Our research group has described previously that Lasiodora sp. venom produces bradycardia in the isolated rat heart. In the present work, we sought to evaluate the vascular effect of Lasiodora sp. venom and to isolate the vasoactive compounds from the venom. The results showed that Lasiodora spider venom induced a concentration-dependent vasodilation in rat aortic rings, which was dependent on the presence of a functional endothelium and abolished by the nitric oxide synthase (NOS) inhibitor L-NAME. Western blot experiments revealed that the venom also increased endothelial NOS function by increasing phosphorylation of the Ser¹¹⁷⁷ residue. Assay-directed fractionation isolated a vasoactive fraction from Lasiodora sp. venom. Mass spectrometry (MS) and nuclear magnetic resonance (NMR) assays identified a mixture of two compounds: adenosine diphosphate (ADP, approximately 90%) and adenosine monophosphate (AMP, approximately 10%). The vasodilator effects of Lasiodora sp. whole venom, as well as ADP, were significantly inhibited by suramin, which is a purinergic P2-receptor antagonist. Therefore, the results of the present work indicate that ADP is a main vasodilator component of Lasiodora sp. spider venom.

  12. Brown spider (Loxosceles intermedia) venom triggers endothelial cells death by anoikis.

    Science.gov (United States)

    Nowatzki, Jenifer; Sene, Reginaldo Vieira; Paludo, Katia Sabrina; Rizzo, Luiz Eduardo; Souza-Fonseca-Guimarães, Fernando; Veiga, Silvio Sanches; Nader, Helena Bonciani; Franco, Célia Regina C; Trindade, Edvaldo S

    2012-09-01

    Brown spider (Loxosceles sp.) venom affects the endothelium of vessels and triggers disruptive activity in the subendothelial matrix. The vascular disorders observed after venom exposure include leukocyte and platelet activation, disseminated intravascular coagulation, an increase in vessel permeability and hemorrhage into the dermis. In this study, we report additional evidence regarding the mechanism of endothelial cell cytotoxicity induced by Loxosceles intermedia venom. Exposure to venom led to endothelial cell detachment in a time-dependent manner. Loss of cell anchorage and cell-cell adhesion following venom exposure was accompanied by changes in the distribution of the α₅β₁ integrin and VE-cadherin. An ultrastructural analysis of cells treated with venom revealed morphological alterations characteristic of apoptosis. Moreover, after venom exposure, the ratio between Bax and Bcl-2 proteins was disturbed in favor of Bax. In addition, late apoptosis was only observed in cells detached by the action of venom. Accordingly, there was no increase in apoptosis when cells were exposed to L. intermedia venom in suspension, suggesting that the loss of cell anchorage provides the signal to initiate apoptosis. Thus, L. intermedia venom likely triggers endothelial cell death indirectly through an apoptotic mechanism known as anoikis.

  13. Adaptive evolution of the venom-targeted vWF protein in opossums that eat pitvipers.

    Directory of Open Access Journals (Sweden)

    Sharon A Jansa

    Full Text Available 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.

  14. Venom variation in hemostasis of the southern Pacific rattlesnake (Crotalus oreganus helleri): isolation of hellerase.

    Science.gov (United States)

    Salazar, Ana Maria; Guerrero, Belsy; Cantu, Bruno; Cantu, Esteban; Rodríguez-Acosta, Alexis; Pérez, John C; Galán, Jacob A; Tao, Andy; Sánchez, Elda E

    2009-04-01

    Envenomations by the southern Pacific rattlesnake (Crotalus oreganus helleri) are the most common snakebite accidents in southern California. Intraspecies venom variation may lead to unresponsiveness to antivenom therapy. Even in a known species, venom toxins are recognized as diverse in conformity with interpopulational, seasonal, ontogenetic and individual factors. Five venoms of individual C. oreganus helleri located in Riverside and San Bernardino counties of southern California were studied for their variation in their hemostatic activity. The results demonstrated that Riverside 2 and San Bernardino 1 venoms presented the highest lethal activity without hemorrhagic activity. In contrast, San Bernardino 2 and 3 venoms had the highest hemorrhagic and fibrinolytic activities with low lethal and coagulant activities. Riverside 1, Riverside 2 and San Bernardino 1 venoms presented a significant thrombin-like activity. San Bernardino 2 and 3 venoms presented an insignificant thrombin-like activity. In relation to the fibrinolytic activity, San Bernardino 3 venom was the most active on fibrin plates, which was in turn neutralized by metal chelating inhibitors. These results demonstrate the differences amongst C. oreganus helleri venoms from close localities. A metalloproteinase, hellerase, was purified by anionic and cationic exchange chromatographies from San Bernardino 3 venom. Hellerase exhibited the ability to break fibrin clots in vitro, which can be of biomedically importance in the treatment of heart attacks and strokes.

  15. [Effects of venom from Sclerodermus sichuanensis Xiao on pupa of Tenebrio molitor].

    Science.gov (United States)

    Zhuo, Zhi-Hang; Yang, Wei; Qin, Huan; Yang, Chun-Ping; Yang, Hua; Xu, Dan-Ping

    2013-11-01

    To explore the regulatory mechanisms of parasitism of Sclerodermus sichuanensis on Tenebrio molitor, the methods of natural parasitism and venom injection were adopted to investigate the effects of the venom from S. sichuanensis on the pupa of T. molitor in the parasitic process. Under venom injection, the paralytic degree of the pupa had a positive correlation with the concentration of injected venom, and the number of recovered pupa had a negative correlation with the injected venom concentration. The T. molitor pupa was in slight and reversible paralysis when injected with 0.01 VRE (venom reservoir equivalent) of venom, and in non-reversible and complete paralysis when 0.2 VRE was injected. The pupa died massively and appeared a wide range of melanization when injected with soil bacterial suspension alone, but the melanization delayed and the mortality declined significantly when the mixed liquor of bacterium and venom was injected. The bacteriostasis of the venom on Staphylococcus aureus was significantly stronger than that on Escherichia coli. Within a definite range of temperature, the paralytic activity decreased significantly with increasing temperature, the bacteriostasis on S. aureus increased significantly, while that on E. coli was opposite. This study showed that the venom from S. sichuanensis had the effects of paralysis, bacteriostasis, inhibiting exuviations, and delaying melanization.

  16. An in vivo examination of the stability of venom from the Australian box jellyfish Chironex fleckeri.

    Science.gov (United States)

    Winter, K L; Isbister, G K; Seymour, J E; Hodgson, W C

    2007-05-01

    We have previously characterised the pharmacological activity of a number of jellyfish venoms with a particular emphasis on the profound cardiovascular effects. It has been suggested that jellyfish venoms are difficult to work with and are sensitive to pH, temperature and chemical changes. The current study aimed to examine the working parameters of the venom of the Australian box jellyfish Chironex fleckeri to enable fractionation and isolation of the toxins with cardiovascular activity. C. fleckeri venom was made up fresh each day and subjected to a number of different environments (i.e. a pH range of 5-9 and a temperature range of 4-30 degrees C). In addition, the effect of freeze drying and reconstituting the venom was investigated. Venom (50 microg/kg, i.v.) produced a transient hypertensive response followed by cardiovascular collapse in anaesthetised rats. This biphasic response was not significantly effected by preparation of the venom at a pH of 5, 7 or 9. Similarly, venom (50 microg/kg, i.v.) did not display a loss of activity when exposed to temperatures of 4, 20 or 30 degrees C for 1.5h. However, the cardiovascular activity was abolished by boiling the venom. Freeze drying, and then reconstituting, the venom did not significantly affect its cardiovascular activity. However, repeated freeze drying and reconstituting of extracted venom resulted in a significantly loss of activity. This study provides a more detailed knowledge of the parameters in which C. fleckeri venom can be used and, while supporting some previous studies, contradicts some of the perceived problems of working with the venom.

  17. A pharmacological and biochemical examination of the geographical variation of Chironex fleckeri venom.

    Science.gov (United States)

    Winter, Kelly L; Isbister, Geoffrey K; McGowan, Sheena; Konstantakopoulos, Nicki; Seymour, Jamie E; Hodgson, Wayne C

    2010-02-15

    Chironex fleckeri (box jellyfish) are found in the northern tropical waters of Australia. Although C. fleckeri have a wide geographical distribution and are able to swim large distances, adults tend to stay in small restricted areas. Clinical data shows that deaths from envenoming have not been recorded in Western Australia, yet numerous fatalities have occurred in Northern Territory and Queensland waters. One explanation for this discrepancy is a geographical variation in venom composition. This study examined the pharmacological and biochemical profiles of C. fleckeri venom from different geographical locations and seasons. Venoms were screened for cytotoxicity using a rat aortic smooth muscle cell line (A7r5). While all venoms caused concentration-dependent cytotoxicity, differences were seen in the potency of venoms from Mission Beach and Weipa, when collected in different seasons, as indicated by IC(50) values. Similarly venoms collected within the same season, from different locations around Australia, displayed marked differences in venom composition as shown by size exclusion HPLC and SDS-PAGE profiles which indicated the absence or reduced quantity of 'peaks' in some venoms. Based on IC(50) data obtained from the cell assay, the effects of the most potent (i.e. from Weipa in 2006) and the least potent (i.e. from Broome in 2007) venoms were examined in anesthetised rats. Both venoms at 10 microg/kg (i.v.) caused a transient hypertensive phase followed by cardiovascular collapse. However, at 4 microg/kg (i.v.) venom from Weipa 2006 caused a transient hypertensive phase followed by a transient decrease in MAP while venom from Broome 2007 only caused a small transient increase in MAP. This study demonstrates that there is considerable geographical variation in the composition of C. fleckeri venoms which is most distinct between specimens from western and eastern Australia and may explain the geographical variation in reported deaths.

  18. Cobra venom cytotoxins; apoptotic or necrotic agents?

    Science.gov (United States)

    Ebrahim, Karim; Shirazi, Farshad H; Mirakabadi, Abbas Zare; Vatanpour, Hossein

    2015-12-15

    Organs homeostasis is controlled by a dynamic balance between cell proliferation and apoptosis. Failure to induction of apoptosis has been implicated in tumor development. Cytotoxin-I (CTX-I) and cytotoxin-II (CTX-II) are two physiologically active polypeptides found in Caspian cobra venom. Anticancer activity and mechanism of cell death induced by these toxins have been studied. The toxins were purified by different chromatographic steps and their cytotoxicity and pattern of cell death were determined by MTT, LDH release, acridine orange/ethidium bromide (AO/EtBr) double staining, flow cytometric analysis, caspase-3 activity and neutral red assays. The IC50 of CTX-II in MCF-7, HepG2, DU-145 and HL-60 was 4.1 ± 1.3, 21.2 ± 4.4, 9.4 ± 1.8 μg/mL and 16.3 ± 1.9 respectively while the IC50 of this toxin in normal MDCK cell line was 54.5 ± 3.9 μg/mL. LDH release suddenly increase after a specific toxins concentrations in all cell lines. AO/EtBr double staining, flow cytometric analysis and caspase-3 activity assay confirm dose and time-dependent induction of apoptosis by both toxins. CTX-I and CTX-II treated cells lost their lysosomal membrane integrity and couldn't uptake neutral red day. CTX-I and CTX-II showed significant anticancer activity with minimum effects on normal cells and better IC50 compared to current anticancer drug; cisplatin. They induce their apoptotic effect via lysosomal pathways and release of cathepsins to cytosol. These effects were seen in limited rage of toxins concentrations and pattern of cell death rapidly changes to necrosis by increase in toxin's concentration. In conclusion, significant apoptogenic effects of these toxins candidate them as a possible anticancer agent.

  19. Review and synthesis of the effects of climate change on amphibians.

    Science.gov (United States)

    Li, Yiming; Cohen, Jeremy M; Rohr, Jason R

    2013-06-01

    Considerable progress has been made in understanding the responses of amphibians to climate change, with successful research carried out on climate change-associated shifts in amphibian phenology, elevational distributions and amphibian-parasite interactions. We review and synthesize the literature on this topic, emphasizing acutely lethal, sublethal, indirect and positive effects of climate change on amphibians, and major research gaps. For instance, evidence is lacking on poleward shifts in amphibian distributions and on changes in body sizes and morphologies of amphibians in response to climate change. We have limited information on amphibian thermal tolerances, thermal preferences, dehydration breaths, opportunity costs of water conserving behaviors and actual temperature and moisture ranges amphibians experience. Even when much of this information is available, there remains little evidence that climate change is acutely lethal to amphibians. This suggests that if climate change is contributing to declines, it might be through effects that are not acutely lethal, indirect, or both, but evidence in support of this suggestion is necessary. In fact, evidence that climate change is directly contributing to amphibian declines is weak, partly because researchers have not often ruled out alternative hypotheses, such as chytrid fungus or climate-fungus interactions. Consequently, we recommend that amphibian-climate research shift from primarily inductive, correlational approach as to studies that evaluate alternative hypotheses for declines. This additional rigor will require interdisciplinary collaborations, estimates of costs and benefits of climate change to amphibian fitness and populations, and the integration of correlative field studies, experiments on 'model' amphibian species, and mathematical and functional, physiological models.

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

    Science.gov (United States)

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

    2016-01-01

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

  1. Venom Gland Transcriptomic and Proteomic Analyses of the Enigmatic Scorpion Superstitionia donensis (Scorpiones: Superstitioniidae), with Insights on the Evolution of Its Venom Components

    Science.gov (United States)

    Santibáñez-López, Carlos E.; Cid-Uribe, Jimena I.; Batista, Cesar V. F.; Ortiz, Ernesto; Possani, Lourival D.

    2016-01-01

    Venom gland transcriptomic and proteomic analyses have improved our knowledge on the diversity of the heterogeneous components present in scorpion venoms. However, most of these studies have focused on species from the family Buthidae. To gain insights into the molecular diversity of the venom components of scorpions belonging to the family Superstitioniidae, one of the neglected scorpion families, we performed a transcriptomic and proteomic analyses for the species Superstitionia donensis. The total mRNA extracted from the venom glands of two specimens was subjected to massive sequencing by the Illumina protocol, and a total of 219,073 transcripts were generated. We annotated 135 transcripts putatively coding for peptides with identity to known venom components available from different protein databases. Fresh venom collected by electrostimulation was analyzed by LC-MS/MS allowing the identification of 26 distinct components with sequences matching counterparts from the transcriptomic analysis. In addition, the phylogenetic affinities of the found putative calcins, scorpines, La1-like peptides and potassium channel κ toxins were analyzed. The first three components are often reported as ubiquitous in the venom of different families of scorpions. Our results suggest that, at least calcins and scorpines, could be used as molecular markers in phylogenetic studies of scorpion venoms. PMID:27941686

  2. Viper venom induced inflammation with Montivipera xanthina (Gray, 1849) and the anti-snake venom activities of Artemisia absinthium L. in rat.

    Science.gov (United States)

    Nalbantsoy, Ayse; Erel, Sura Baykan; Köksal, Cinel; Göçmen, Bayram; Yıldız, Mehmet Zülfü; Karabay Yavaşoğlu, Nefise Ülkü

    2013-04-01

    The present study was conducted to explore the characterization of Montivipera xanthina crude venom partially by in vitro and in vivo and the anti-snake venom activities of Artemisia absinthium L. in comparison with carrageenan-induced acute inflammation model in rats. The LD50 value was estimated as 8.78 mg/kg within 24 h by different venom doses administrated intraperitoneally in mice. The IC50 value was 0.43 ± 0.18 μg/ml after 48 h treatment while the calculated value was 0.73 ± 0.10 μg/ml for the culture media totally refreshed after 2 h treatment with venom. Wistar rats were treated intraperitoneally with A. absinthium extract, 30 min before venom or carrageenan was injected subplantarly into the left hind paw. Intraperitoneal administration of 25 and 50 mg/kg extract was inhibited venom induced paw swelling at 0.5, 1, 2 and 3 h (p in vivo toxicity and inflammatory actions and in vitro cytotoxic actions of crude M. xanthina venom were performed as a first report and inhibition of venom-induced inflammation by methanolic extract of A. absinthium was described.

  3. Combined venomics, venom gland transcriptomics, bioactivities, and antivenomics of two Bothrops jararaca populations from geographic isolated regions within the Brazilian Atlantic rainforest.

    Science.gov (United States)

    Gonçalves-Machado, Larissa; Pla, Davinia; Sanz, Libia; Jorge, Roberta Jeane B; Leitão-De-Araújo, Moema; Alves, Maria Lúcia M; Alvares, Diego Janisch; De Miranda, Joari; Nowatzki, Jenifer; de Morais-Zani, Karen; Fernandes, Wilson; Tanaka-Azevedo, Anita Mitico; Fernández, Julián; Zingali, Russolina B; Gutiérrez, José María; Corrêa-Netto, Carlos; Calvete, Juan J

    2016-03-01

    Bothrops jararaca is a slender and semi-arboreal medically relevant pit viper species endemic to tropical and subtropical forests in southern Brazil, Paraguay, and northern Argentina (Misiones). Within its geographic range, it is often abundant and is an important cause of snakebite. Although no subspecies are currently recognized, geographic analyses have revealed the existence of two well-supported B. jararaca clades that diverged during the Pliocene ~3.8Mya and currently display a southeastern (SE) and a southern (S) Atlantic rainforest (Mata Atlântica) distribution. The spectrum, geographic variability, and ontogenetic changes of the venom proteomes of snakes from these two B. jararaca phylogroups were investigated applying a combined venom gland transcriptomic and venomic analysis. Comparisons of the venom proteomes and transcriptomes of B. jararaca from the SE and S geographic regions revealed notable interpopulational variability that may be due to the different levels of population-specific transcriptional regulation, including, in the case of the southern population, a marked ontogenetic venom compositional change involving the upregulation of the myotoxic PLA2 homolog, bothropstoxin-I. This population-specific marker can be used to estimate the proportion of venom from the southern population present in the B. jararaca venom pool used for the Brazilian soro antibotrópico (SAB) antivenom production. On the other hand, the southeastern population-specific D49-PLA2 molecules, BinTX-I and BinTX-II, lend support to the notion that the mainland ancestor of Bothrops insularis was originated within the same population that gave rise to the current SE B. jararaca phylogroup, and that this insular species endemic to Queimada Grande Island (Brazil) expresses a pedomorphic venom phenotype. Mirroring their compositional divergence, the two geographic B. jararaca venom pools showed distinct bioactivity profiles. However, the SAB antivenom manufactured in Vital Brazil

  4. Parasites lost? An overlooked hypothesis for the evolution of alternative reproductive strategies in amphibians.

    Science.gov (United States)

    Todd, Brian D

    2007-11-01

    Amphibians exhibit the greatest diversity of reproductive strategies of all tetrapod vertebrates. While authors have traditionally attributed the evolution of these strategies to factors such as complex topography, unpredictable larval environments, and predation on larvae and eggs, support for any of these hypotheses has been limited. Importantly, most authors have ignored parasites, including unicellular pathogens and multicellular parasites, as selective agents capable of influencing amphibian evolution. Insights in disease transmission, amphibian immunity, and their interaction with various life histories require that we consider parasites to be selective pressures in our exploration of the evolution of amphibian reproductive strategies. I review recent findings and describe how these principles converge to form a novel conceptual hypothesis for the evolution of alternative reproductive strategies in amphibians. I offer some specific predictions and recommend that parasites be considered with other selective pressures when constructing formal, falsifiable hypotheses during evaluative studies of amphibian reproductive behavior.

  5. The Current and Historical Distribution of Special Status Amphibians at the Livermore Site and Site 300

    Energy Technology Data Exchange (ETDEWEB)

    Hattem, M V; Paterson, L; Woollett, J

    2008-08-20

    65 surveys were completed in 2002 to assess the current distribution of special status amphibians at the Lawrence Livermore National Laboratory's (LLNL) Livermore Site and Site 300. Combined with historical information from previous years, the information presented herein illustrates the dynamic and probable risk that amphibian populations face at both sites. The Livermore Site is developed and in stark contrast to the mostly undeveloped Site 300. Yet both sites have significant issues threatening the long-term sustainability of their respective amphibian populations. Livermore Site amphibians are presented with a suite of challenges inherent of urban interfaces, most predictably the bullfrog (Rana catesbeiana), while Site 300's erosion issues and periodic feral pig (Sus scrofa) infestations reduce and threaten populations. The long-term sustainability of LLNL's special status amphibians will require active management and resource commitment to maintain and restore amphibian habitat at both sites.

  6. Spider genomes provide insight into composition and evolution of venom and silk.

    Science.gov (United States)

    Sanggaard, Kristian W; Bechsgaard, Jesper S; Fang, Xiaodong; Duan, Jinjie; Dyrlund, Thomas F; Gupta, Vikas; Jiang, Xuanting; Cheng, Ling; Fan, Dingding; Feng, Yue; Han, Lijuan; Huang, Zhiyong; Wu, Zongze; Liao, Li; Settepani, Virginia; Thøgersen, Ida B; Vanthournout, Bram; Wang, Tobias; Zhu, Yabing; Funch, Peter; Enghild, Jan J; Schauser, Leif; Andersen, Stig U; Villesen, Palle; Schierup, Mikkel H; Bilde, Trine; Wang, Jun

    2014-05-06

    Spiders are ecologically important predators with complex venom and extraordinarily tough silk that enables capture of large prey. Here we present the assembled genome of the social velvet spider and a draft assembly of the tarantula genome that represent two major taxonomic groups of spiders. The spider genomes are large with short exons and long introns, reminiscent of mammalian genomes. Phylogenetic analyses place spiders and ticks as sister groups supporting polyphyly of the Acari. Complex sets of venom and silk genes/proteins are identified. We find that venom genes evolved by sequential duplication, and that the toxic effect of venom is most likely activated by proteases present in the venom. The set of silk genes reveals a highly dynamic gene evolution, new types of silk genes and proteins, and a novel use of aciniform silk. These insights create new opportunities for pharmacological applications of venom and biomaterial applications of silk.

  7. Cardiotoxic effects of venom fractions from the Australian box jellyfish Chironex fleckeri on human myocardiocytes.

    Science.gov (United States)

    Saggiomo, Silvia L A; Seymour, Jamie E

    2012-09-01

    An investigation into the cardiotoxic effects in human cardiomyocytes of different fractions (as produced from an FPLC) of the venom from Chironex fleckeri showed that whole venom caused cardiac cell death in minutes, measured as cell detachment using xCELLigence technology. However, only one fraction of the venom was responsible for this effect. When all extracted venoms were recombined a similar result was seen for the toxic fraction, however these effects were slower than unfractionated venom alone even though the concentrations were similar. The difference in the results between fractioned and unfractionated venom may have been caused by compounds remaining in the FPLC column, which may interact with the toxic fraction to cause rapid cell detachment or death.

  8. Proteomic Analyses of Agkistrodon contortrix contortrix Venom Using 2D Electrophoresis and MS Techniques.

    Science.gov (United States)

    Bocian, Aleksandra; Urbanik, Małgorzata; Hus, Konrad; Łyskowski, Andrzej; Petrilla, Vladimír; Andrejčáková, Zuzana; Petrillová, Monika; Legáth, Jaroslav

    2016-12-13

    Snake venom is a complex mixture of proteins and peptides which in the Viperidae is mainly hemotoxic. The diversity of these components causes the venom to be an extremely interesting object of study. Discovered components can be used in search for new pharmaceuticals used primarily in the treatment of diseases of the cardiovascular system. In order to determine the protein composition of the southern copperhead venom, we have used high resolution two dimensional electrophoresis and MALDI ToF/ToF MS-based identification. We have identified 10 groups of proteins present in the venom, of which phospholipase A₂ and metalloprotease and serine proteases constitute the largest groups. For the first time presence of 5'-nucleotidase in venom was found in this group of snakes. Three peptides present in the venom were also identified. Two of them as bradykinin-potentiating agents and one as an inhibitor.

  9. Proteomic Analyses of Agkistrodon contortrix contortrix Venom Using 2D Electrophoresis and MS Techniques

    Directory of Open Access Journals (Sweden)

    Aleksandra Bocian

    2016-12-01

    Full Text Available Snake venom is a complex mixture of proteins and peptides which in the Viperidae is mainly hemotoxic. The diversity of these components causes the venom to be an extremely interesting object of study. Discovered components can be used in search for new pharmaceuticals used primarily in the treatment of diseases of the cardiovascular system. In order to determine the protein composition of the southern copperhead venom, we have used high resolution two dimensional electrophoresis and MALDI ToF/ToF MS-based identification. We have identified 10 groups of proteins present in the venom, of which phospholipase A2 and metalloprotease and serine proteases constitute the largest groups. For the first time presence of 5′-nucleotidase in venom was found in this group of snakes. Three peptides present in the venom were also identified. Two of them as bradykinin-potentiating agents and one as an inhibitor.

  10. Histopathological evaluation in experimental envenomation of dogs with Crotalus durissus terrificus venom

    Directory of Open Access Journals (Sweden)

    F. Sangiorgio

    2008-01-01

    Full Text Available The present work evaluated histopathological aspects in experimental envenomation of dogs with Crotalus durissus terrificus venom. Twenty-eight mixed breed adult dogs were divided into three groups of seven animals each: Group I - only venom; Group II - venom + 50ml antiophidic serum + fluid therapy; Group III - venom + 50ml antiophidic serum + fluid therapy + urine alkalization. Lyophilized venom of Crotalus durissus terrificus was reconstituted in saline solution and inoculated subcutaneously at the dose of 1mg/kg body weight. Three animals of each group were subjected to euthanasia, and their muscular tissue, brain, spleen, kidneys, heart, lungs, stomach, small and large intestines, and popliteal lymph node fragments were collected for histopathological evaluation. There was myonecrosis in the inoculated limb, renal tubular degeneration, lymphoid hyperplasia of spleen, and unspecific reactive hepatitis. These results show the antigenicity and action of the venom on the immune system.

  11. Efficacy of tannins from Mimosa pudica and tannic acid in neutralizing cobra (Naja kaouthia venom

    Directory of Open Access Journals (Sweden)

    FY Sia

    2011-01-01

    Full Text Available In the present study, the effectiveness of Mimosa pudica tannins (MPT in neutralizing the lethality of Naja kaouthia venom was compared with commercially derived tannins. Preincubation of MPT with N. kaouthia venom maintained 100% survival of mice after 24 hours. The mouse group in which there was no preincubation, no protection against the effects of the venom was observed. M. pudica tannin was found to be more effective in neutralizing the lethality of N. kaouthia venom when compared to commercial tannic acid. Two protein spots were missing in the two-dimensional gel electrophoresis (2-DE of the MPT treated mouse indicating the down-regulation of venom proteins. The results from this study indicated that tannins obtained from M. pudica are better than tannic acid in neutralizing the lethality of N. kaouthia venom in vitro. However, further investigations are required to establish that M. pudica has potential for treating N. kaouthia snakebites.

  12. Ctenus medius and Phoneutria nigriventer spiders venoms share noxious proinflammatory activities.

    Science.gov (United States)

    Okamoto, Cinthya Kimori; Gonçalves-De-Andrade, Rute M; Queiroz, Giselle Pidde; Gutierez, Vanessa P; De Almeida, Daniel Manzoni; Cury, Yara; Bertani, Rogério; Portaro, Fernanda C V; Tambourgi, Denise V

    2009-01-01

    Ctenus medius Keyserling, 1891 (Araneae: Ctenidae) co-occurs in various microhabitats of the Brazilian Atlantic Forest and can be easily misidentified as the medically important spider Phoneutria nigriventer Keyserling, 1981 (Ctenidae). Despite being phylogenetically close to Phoneutria, no data are available about the toxic potential of Ctenus medius venom. Here we show that, although presenting different profile of protein composition, C. medius venom displays some of the toxic properties exhibited by P. nigriventer venom, including proteolytic, hyaluronidasic and phospholipasic activities, as well as the ability of causing hyperalgesia and edema. Moreover, C. medius venom interferes in the activation of the complement system in concentrations that P. nigriventer venom is inactive. Thus, these data show that venoms of spiders from Ctenidae family share important proinflammatory properties and suggest that the C. medius bite may have an important noxious effect in human accidents.

  13. Pharmacology of the GABAB receptor in amphibian retina.

    Science.gov (United States)

    Tian, N; Slaughter, M M

    1994-10-17

    Amacrine and ganglion cells in the amphibian retina contain GABAB, as well as GABAA, receptors. Baclofen, a GABAB agonist, hyperpolarizes the dark membrane potential of these third order neurons and makes their light responses more transient. GABAB receptors in the retina have a similar agonist profile to GABAB receptors described at other sites in the brain. Namely, preferential activation by the R-enantiomer of baclofen, and agonist sensitivity in the order 3-aminopropylphosphinic acid > baclofen > 3-aminopropylphosphonic acid. The GABAB receptor was not activated by 4-aminobutylphosphonic acid. Several antagonists, such as phaclofen, saclofen, and 2-hydroxysaclofen, were ineffective in the amphibian retina. However, CGP35348 blocked the action of applied baclofen and produced effects on the light response that were opposite to those of baclofen. Applied agonists and antagonists support the hypothesis that GABAB receptors serve to regulate the balance of sustained and transient signals to the inner retina.

  14. Reptiles and Amphibians of the Addo Elephant National Park

    Directory of Open Access Journals (Sweden)

    W.R. Branch

    1987-10-01

    Full Text Available The results of a survey of the reptiles and amphibians of the Addo Elephant National Park (AENP are presented. A total of 49 species, comprising 16 amphibians, 14 lizards, 15 snakes and 4 chelonians, occur in the AENP. Observations on the biology and distribution of these species in the AENP are given, and the relative composition and diversity is compared with the herpetofauna of the surrounding eastern Cape and the more distant Kruger National Park. The zoogeographic affinities of the AENP herpetofauna are similar to those of the surrounding eastern Cape (i.e. Cape Temperate 46,9, Temperate- Transitional 16,3, Eastern Tropical Transitional 10,2, Western Tropical Transitional 8,2, Tropical East Coast Littoral 2,0 and Temperate Wideranging 16,3. Resource partitioning among the AENP herpetofauna is discussed and the conservation status of the species summarised. A list of species that may still be collected within the AENP is included.

  15. Congenital malformations of the vertebral column in ancient amphibians.

    Science.gov (United States)

    Witzmann, F; Rothschild, B M; Hampe, O; Sobral, G; Gubin, Y M; Asbach, P

    2014-04-01

    Temnospondyls, the largest group of Palaeozoic and Mesozoic amphibians, primitively possess rhachitomous vertebrae with multipartite centra (consisting of one horse-shoe-shaped inter- and paired pleurocentra). In a group of temnospondyls, the stereospondyls, the intercentra became pronounced and disc-like, whereas the pleurocentra were reduced. We report the presence of congenital vertebral malformations (hemi, wedge and block vertebrae) in Permian and Triassic temnospondyls, showing that defects of formation and segmentation in the tetrapod vertebral column represent a fundamental failure of somitogenesis that can be followed throughout tetrapod evolution. This is irrespective of the type of affected vertebra, that is, rhachitomous or stereospondylous, and all components of the vertebra can be involved (intercentrum, pleurocentrum and neural arch), either together or independently on their own. This is the oldest known occurrence of wedge vertebra and congenital block vertebra described in fossil tetrapods. The frequency of vertebral congenital malformations in amphibians appears unchanged from the Holocene.

  16. Transitions between sex-determining systems in reptiles and amphibians.

    Science.gov (United States)

    Sarre, Stephen D; Ezaz, Tariq; Georges, Arthur

    2011-01-01

    Important technological advances in genomics are driving a new understanding of the evolution of sex determination in vertebrates. In particular, comparative chromosome mapping in reptiles has shown an intriguing distribution of homology in sex chromosomes across reptile groups. When this new understanding is combined with the widespread distribution of genetic and temperature-dependent sex-determination mechanisms among reptiles, it is apparent that transitions between modes have occurred many times, as they have for amphibians (particularly between male and female heterogamety). It is also likely that thermosensitivity in sex determination is a key factor in those transitions in reptiles, and possibly in amphibians too. New models of sex determination involving temperature thresholds are providing the framework for the investigation of transitions and making possible key predictions about the homologies and sex-determination patterns expected among taxa in these groups. Molecular cytogenetics and other genomic approaches are essential to providing the fundamental material necessary to make advances in this field.

  17. Special Issue: Viruses Infecting Fish, Amphibians, and Reptiles

    Directory of Open Access Journals (Sweden)

    V. Gregory Chinchar

    2011-09-01

    Full Text Available Although viruses infecting and affecting humans are the focus of considerable research effort, viruses that target other animal species, including cold-blooded vertebrates, are receiving increased attention. In part this reflects the interests of comparative virologists, but increasingly it is based on the impact that many viruses have on ecologically and commercially important animals. Frogs and other amphibians are sentinels of environmental health and their disappearance following viral or fungal (chytrid infection is a cause for alarm. Likewise, because aquaculture and mariculture are providing an increasingly large percentage of the “seafood” consumed by humans, viral agents that adversely impact the harvest of cultured fish and amphibians are of equal concern. [...

  18. Conservation genetics and genomics of amphibians and reptiles.

    Science.gov (United States)

    Shaffer, H Bradley; Gidiş, Müge; McCartney-Melstad, Evan; Neal, Kevin M; Oyamaguchi, Hilton M; Tellez, Marisa; Toffelmier, Erin M

    2015-01-01

    Amphibians and reptiles as a group are often secretive, reach their greatest diversity often in remote tropical regions, and contain some of the most endangered groups of organisms on earth. Particularly in the past decade, genetics and genomics have been instrumental in the conservation biology of these cryptic vertebrates, enabling work ranging from the identification of populations subject to trade and exploitation, to the identification of cryptic lineages harboring critical genetic variation, to the analysis of genes controlling key life history traits. In this review, we highlight some of the most important ways that genetic analyses have brought new insights to the conservation of amphibians and reptiles. Although genomics has only recently emerged as part of this conservation tool kit, several large-scale data sources, including full genomes, expressed sequence tags, and transcriptomes, are providing new opportunities to identify key genes, quantify landscape effects, and manage captive breeding stocks of at-risk species.

  19. Early 1900 s detection of Batrachochytrium dendrobatidis in Korean amphibians.

    Science.gov (United States)

    Fong, Jonathan J; Cheng, Tina L; Bataille, Arnaud; Pessier, Allan P; Waldman, Bruce; Vredenburg, Vance T

    2015-01-01

    The pathogenic fungus Batrachochytrium dendrobatidis (Bd) is a major conservation concern because of its role in decimating amphibian populations worldwide. We used quantitative PCR to screen 244 museum specimens from the Korean Peninsula, collected between 1911 and 2004, for the presence of Bd to gain insight into its history in Asia. Three specimens of Rugosa emeljanovi (previously Rana or Glandirana rugosa), collected in 1911 from Wonsan, North Korea, tested positive for Bd. Histology of these positive specimens revealed mild hyperkeratosis - a non-specific host response commonly found in Bd-infected frogs - but no Bd zoospores or zoosporangia. Our results indicate that Bd was present in Korea more than 100 years ago, consistent with hypotheses suggesting that Korean amphibians may be infected by endemic Asian Bd strains.

  20. Amphibian commerce as a likely source of pathogen pollution.

    Science.gov (United States)

    Picco, Angela M; Collins, James P

    2008-12-01

    The commercial trade of wildlife occurs on a global scale. In addition to removing animals from their native populations, this trade may lead to the release and subsequent introduction of nonindigenous species and the pathogens they carry. Emerging infectious diseases, such as chytridiomycosis caused by the chytrid fungus Batrachochytrium dendrobatidis (Bd), and ranaviral disease have spread with global trade in amphibians and are linked to amphibian declines and die-offs worldwide, which suggests that the commercial trade in amphibians may be a source of pathogen pollution. We screened tiger salamanders involved in the bait trade in the western United States for both ranaviruses and Bd with polymerase chain reaction and used oral reports from bait shops and ranavirus DNA sequences from infected bait salamanders to determine how these animals and their pathogens are moved geographically by commerce. In addition, we conducted 2 surveys of anglers to determine how often tiger salamanders are used as bait and how often they are released into fishing waters by anglers, and organized bait-shop surveys to determine whether tiger salamanders are released back into the wild after being housed in bait shops. Ranaviruses were detected in the tiger salamander bait trade in Arizona, Colorado, and New Mexico, and Bd was detected in Arizona bait shops. Ranaviruses were spread geographically through the bait trade. All tiger salamanders in the bait trade were collected from the wild, and in general they moved east to west and north to south, bringing with them their multiple ranavirus strains. Finally, 26-73% of anglers used tiger salamanders as fishing bait, 26-67% of anglers released tiger salamanders bought as bait into fishing waters, and 4% of bait shops released tiger salamanders back into the wild after they were housed in shops with infected animals. The tiger salamander bait trade in the western United States is a useful model for understanding the consequences of the

  1. Reptiles and amphibians of the Savannah River Plant

    Energy Technology Data Exchange (ETDEWEB)

    Gibbons, J.W.; Patterson, K.K.

    1978-11-01

    Taxonomic, distributional, and ecological information on the reptiles and amphibians of the Savannah River Plant (SRP) is provided. The purpose of such a presentation is to give a professional biologist an initial familiarity with herpetology on the SRP, and to provide sufficient comprehensive information to an ecologist, regardless of his experience in herpetology, to permit him to undertake studies that in some manner incorporate the herpetofauna of the SRP. (ERB)

  2. Evaluating the links between climate, disease spread, and amphibian declines.

    Science.gov (United States)

    Rohr, Jason R; Raffel, Thomas R; Romansic, John M; McCallum, Hamish; Hudson, Peter J

    2008-11-11

    Human alteration of the environment has arguably propelled the Earth into its sixth mass extinction event and amphibians, the most threatened of all vertebrate taxa, are at the forefront. Many of the worldwide amphibian declines have been caused by the chytrid fungus, Batrachochytrium dendrobatidis (Bd), and two contrasting hypotheses have been proposed to explain these declines. Positive correlations between global warming and Bd-related declines sparked the chytrid-thermal-optimum hypothesis, which proposes that global warming increased cloud cover in warm years that drove the convergence of daytime and nighttime temperatures toward the thermal optimum for Bd growth. In contrast, the spatiotemporal-spread hypothesis states that Bd-related declines are caused by the introduction and spread of Bd, independent of climate change. We provide a rigorous test of these hypotheses by evaluating (i) whether cloud cover, temperature convergence, and predicted temperature-dependent Bd growth are significant positive predictors of amphibian extinctions in the genus Atelopus and (ii) whether spatial structure in the timing of these extinctions can be detected without making assumptions about the location, timing, or number of Bd emergences. We show that there is spatial structure to the timing of Atelopus spp. extinctions but that the cause of this structure remains equivocal, emphasizing the need for further molecular characterization of Bd. We also show that the reported positive multi-decade correlation between Atelopus spp. extinctions and mean tropical air temperature in the previous year is indeed robust, but the evidence that it is causal is weak because numerous other variables, including regional banana and beer production, were better predictors of these extinctions. Finally, almost all of our findings were opposite to the predictions of the chytrid-thermal-optimum hypothesis. Although climate change is likely to play an important role in worldwide amphibian declines

  3. Global Amphibian Extinction Risk Assessment for the Panzootic Chytrid Fungus

    OpenAIRE

    Fisher, Matthew C.; Michael Veith; Susan Walker; Garner, Trenton W. J.; Jaime Bosch; Sebastian Schmidtlein; Jon Bielby; Jos Kielgast; Dennis Rödder; Stefan Lötters

    2009-01-01

    Species are being lost at increasing rates due to anthropogenic effects, leading to the recognition that we are witnessing the onset of a sixth mass extinction. Emerging infectious disease has been shown to increase species loss and any attempts to reduce extinction rates need to squarely confront this challenge. Here, we develop a procedure for identifying amphibian species that are most at risk from the effects of chytridiomycosis by combining spatial analyses of key host life-history varia...

  4. Landscape-stream interactions and habitat conservation for amphibians.

    Science.gov (United States)

    Ficetola, Gentile Francesco; Marziali, Laura; Rossaro, Bruno; De Bernardi, Fiorenza; Padoa-Schioppa, Emilio

    2011-06-01

    Semiaquatic organisms depend on the features of both water bodies and landscapes; the interplay between terrestrial and aquatic systems might influence the semiaquatic communities, determining the scale at which management would be more effective. However, the consequences of such interplay are not frequently quantified, particularly at the community level. We analyzed the distribution of amphibians to evaluate whether the influence of landscape features on freshwater ecosystems can have indirect consequences at both the species and community level. We surveyed 74 streams in northern Italy to obtain data on breeding amphibians, water, and microhabitat features; we also measured features of surrounding landscapes. We used an information-theoretic approach and structural equation models to compare hypotheses on causal relationships between species distribution and variables measured at multiple levels. We also used a constrained redundancy analyses to evaluate causal relationships between multivariate descriptors of habitat features and community composition. Distribution of Salamandra salamandra was related to landscape, hydrological, and water characteristics: salamanders were more frequent in permanent streams with low phosphate concentration within natural landscapes. Water characteristics were dependent on landscape: streams in natural landscapes had less phosphates. Landscape influenced the salamander both directly and indirectly through its influence on phosphates. Community structure was determined by both landscape and water characteristics. Several species were associated with natural landscapes, and with particular water characteristics. Landscape explained a significant proportion of variability of water characteristics; therefore it probably had indirect effects on community. Upland environments play key roles for amphibians, for example, as the habitat of adults, but upland environments also have indirect effects on the aquatic life stages, mediated

  5. Sperm motility of externally fertilizing fish and amphibians.

    Science.gov (United States)

    Browne, R K; Kaurova, S A; Uteshev, V K; Shishova, N V; McGinnity, D; Figiel, C R; Mansour, N; Agney, D; Wu, M; Gakhova, E N; Dzyuba, B; Cosson, J

    2015-01-01

    We review the phylogeny, sperm competition, morphology, physiology, and fertilization environments of the sperm of externally fertilizing fish and amphibians. Increased sperm competition in both fish and anurans generally increases sperm numbers, sperm length, and energy reserves. The difference between the internal osmolarity and iconicity of sperm cells and those of the aquatic medium control the activation, longevity, and velocity of sperm motility. Hypo-osmolarity of the aquatic medium activates the motility of freshwater fish and amphibian sperm and hyperosmolarity activates the motility of marine fish sperm. The average longevity of the motility of marine fish sperm (~550 seconds) was significantly (P fish sperm (~150 seconds), with the longevities of both marine and freshwater fish being significantly (P fish (140 μm/s) or freshwater fish (135 μm/s) sperm. The longevity of the sperm of giant salamanders (Cryptobranchoidea) of approximately 600 seconds was greater than that of freshwater fish sperm but much lower than anuran sperm. Our research and information from the literature showed that higher osmolarities promote greater longevity in anuran sperm, and some freshwater fish sperm, and that anuran and cryptobranchid sperm maintained membrane integrity long after the cessation of motility, demonstrating a preferential sharing of energy reserves toward the maintenance of membrane integrity. The maintenance of the membrane integrity of anuran sperm in fresh water for up to 6 hours showed an extremely high osmotic tolerance relative to fish sperm. The very high longevity and osmotic tolerance of anuran sperm and high longevity of cryptobranchid sperm, relative to those of freshwater fish, may reflect the complex fertilization history of amphibian sperm in general and anurans reversion from internal to external fertilization. Our findings provide a greater understanding of the reproductive biology of externally fertilizing fish and amphibians, and a

  6. Evaluation of cytotoxic activities of snake venoms toward breast (MCF-7) and skin cancer (A-375) cell lines.

    Science.gov (United States)

    Bradshaw, Michael J; Saviola, Anthony J; Fesler, Elizabeth; Mackessy, Stephen P

    2016-08-01

    Snake venoms are mixtures of bioactive proteins and peptides that exhibit diverse biochemical activities. This wide array of pharmacologies associated with snake venoms has made them attractive sources for research into potentially novel therapeutics, and several venom-derived drugs are now in use. In the current study we performed a broad screen of a variety of venoms (61 taxa) from the major venomous snake families (Viperidae, Elapidae and "Colubridae") in order to examine cytotoxic effects toward MCF-7 breast cancer cells and A-375 melanoma cells. MTT cell viability assays of cancer cells incubated with crude venoms revealed that most venoms showed significant cytotoxicity. We further investigated venom from the Red-bellied Blacksnake (Pseudechis porphyriacus); venom was fractionated by ion exchange fast protein liquid chromatography and several cytotoxic components were isolated. SDS-PAGE and MALDI-TOF mass spectrometry were used to identify the compounds in this venom responsible for the cytotoxic effects. In general, viper venoms were potently cytotoxic, with MCF-7 cells showing greater sensitivity, while elapid and colubrid venoms were much less toxic; notable exceptions included the elapid genera Micrurus, Naja and Pseudechis, which were quite cytotoxic to both cell lines. However, venoms with the most potent cytotoxicity were often not those with low mouse LD50s, including some dangerously venomous viperids and Australian elapids. This study confirmed that many venoms contain cytotoxic compounds, including catalytic PLA2s, and several venoms also showed significant differential toxicity toward the two cancer cell lines. Our results indicate that several previously uncharacterized venoms could contain promising lead compounds for drug development.

  7. Standardization of anti-lethal toxin potency test of antivenoms prepared from two different Agkistrodon halys venoms

    Directory of Open Access Journals (Sweden)

    K. H. Lee

    2006-01-01

    Full Text Available In Korea, antivenoms for the treatment of patients bitten by venomous snakes have been imported from Japan or China. Although there is cross-reactivity between these antibodies and venoms from snakes indigenous to Korea (e.g. Agkistrodon genus, protection is not optimal. Antivenoms specifically prepared to neutralize Korean snake venoms could be more effective, with fewer side effects. To this end, we established an infrastructure to develop national standards and created a standardized method to evaluate the efficacy of two horse-derived antivenoms using mouse lethal toxin test. Additionally, we determined the antivenoms neutralizing activity against lethal doses (LD50 of Agkistrodon halys (from Japan and Jiangzhe Agkistrodon halys (from China venoms. We also performed cross-neutralization tests using probit analysis on each pairing of venom and antivenom in order to check the possibility of using Jiangzhe A. halys venom as a substitute for A. halys venom, the current standard. Slope of A. halys venom with A. halys antivenom was 10.2 and that of A. halys venom with Jiangzhe A. halys antivenom was 9.6. However, Slope of Jiangzhe A. halys venom with A. halys antivenom was 4.7 while that of Jiangzhe A. halys venom with Jiangzhe A. halys antivenom was 11.5. Therefore, the significant difference in slope patterns suggests that Jiangzhe A. halys venom cannot be used as a substitute for the standard venom to test the anti-lethal toxin activity of antivenoms (p<0.05.

  8. Purification of the Immunogenic Fractions and Determination of Toxicity in Mesobuthus eupeus (Scorpionida: Buthidae Venom.

    Directory of Open Access Journals (Sweden)

    Mehdi Khoobdel

    2013-12-01

    Full Text Available Scorpions stings are a health problem in many parts of the world. Mesobuthus eupeus (Buthidae is the most prevalent species in the Middle East and Central Asia. Definition of toxicogenic and immunogenic characteristics of the venom is necessary to produce antidote. In this study, the noted properties of M. eupeus venom were evaluated.Venom was obtained by milking M. eupeus scorpions for lyophilization. Toxicity was determined after injecting the venom to albino mice and calculating LD50. Polyclonal antibodies against M. eupeus venom were obtained from immunized rabbits. The CH-Sepharose 4B column was used for isolating the specific antibodies. 10 mg of the affinity-purified antibodies were conjugated with a CH-Sepharose 4B column and M. eupeus venom was applied to the column. The bound fragments were eluted using hydrogen chloride (pH: 2.5. Crude venom and affinity-purified fractions of the venom were analyzed by SDS-PAGE technique.Lethal dose (LD was 8.75, 11.5 and 4.5 mg/kg for IP, SC and IV respectively. The LD50 of M. eupeus venom was 6.95 mg/kg. The crude venom had 12 detectable bands with molecular weights of 140, 70, 50, 33, 30, 27, 22, 18, 14, 10 kDa and two bands less than 5 kDa. The affinity-purified venom presented eight bands. The 27 kDa band was clearly sharper than other bands but 70, 18, 10 and one of the less than 5 kDa bands were not observed.Contrary to popular belief, which know scorpion venom as non-immunogenic composition, the current study was shown that the most fractions of the M. eupeus are immunogenic.

  9. Partial Purification and Characterization of Anticoagulant Factor from the Snake (Echis carinatus) Venom

    OpenAIRE

    2013-01-01

    Objective(s): Snake venoms contain complex mixture of proteins with biological activities. Some of these proteins affect blood coagulation and platelet function in different ways. Snake venom toxin may serve as a starting material for drug design to combat several pathophysiological problems such as cardiovascular disorders. In the present study, purification of anticoagulation factor from venom of snake (Echis carinatus) was studied. Materials and Methods: Anticoagulation activity of crude v...

  10. Differential gene expression profiles in the venom gland/sac of Eumenes pomiformis (Hymenoptera: Eumenidae).

    Science.gov (United States)

    Baek, Ji Hyeong; Lee, Si Hyeock

    2010-06-01

    To search for novel transcripts encoding biologically active venom components, a subtractive cDNA library specific to the venom gland and sac (gland/sac) of a solitary hunting wasp species, Eumenes pomiformis Fabricius (1781), was constructed by suppression subtractive hybridization. A total of 541 expressed sequence tags (ESTs) were clustered and assembled into 102 contigs (31 multiple sequences and 71 singletons). In total, 37 cDNAs were found in the library via BLASTx searching and manual annotation. Eight contigs (337 ESTs) encoding short venom peptides (10 to 16 amino acids) occupied 62% of the library. The deduced amino acid sequence (78 amino acids) of a novel venom peptide transcript shared sequence similarity with trypsin inhibitors and dendrotoxin-like venom peptides known to be K(+) channel blockers, implying that this novel peptide may play a role in the paralysis of prey. In addition to phospholipase A2 and hyaluronidase, which are known to be the main components of wasp venoms, several transcripts encoding enzymes, including three metallopeptidases and a decarboxylase likely involved in the processing and activation of venomous proteins, peptides, amines, and neurotransmitters, were also isolated from the library. The presence of a transcript encoding a putative insulin/insulin-like peptide binding protein suggests that solitary hunting wasps use their venom to control their prey, leading to larval growth cessation. The abundance of these venom components in the venom gland/sac and in the alimentary canal was confirmed by quantitative real-time PCR. Discovery of venom gland/sac-specific transcripts should promote further studies on biologically active components in the venom of solitary hunting wasps.

  11. Pentastomiasis and other parasitic zoonoses from reptiles and amphibians.

    Science.gov (United States)

    Pantchev, Nikola; Tappe, Dennis

    2011-01-01

    Reptiles are growing in popularity as pets.The colonization of reptiles and amphibians by parasites and the resulting disease conditions are the most common problems seen in captive animals.This review focuses on pentastomiasis and sparganosis, important parasitic zoonoses of reptiles and amphibians, respectively, and free living-amoebae. Humans are suitable accidental hosts for some pentastomid species (particularly Armillifer and Porocephalus). In geographical areas with special ethnics, such as in West and Central Africa, and East Asia, 8-45% of the human population can be affected. Usually the larvae are coincidentally found during abdominal surgeries. However, fatalities have been described. Extreme caution is necessary when handling infected reptiles. Ocular or cerebral sparganosis is not uncommonly found in humans in East Asia. This disease is caused by spargana, tapeworm larvae (plerocercoids) of Spirometra sp. The infection occurs when uncooked meat from reptiles or amphibians is applied to wounds or eyes and the parasites migrate directly to human tissue, or by consumption of contaminated food or water. As a consequence of the reptile's predatory behaviour, the full spectrum of endo- and ectoparasites from potential prey animals can be found as transiting parasites in the intestinal tract, e. g. Hymenolepis nana, Cryptosporidium (C.) muris, C parvum or Capillaria hepatica. Occasionally, free-living amoebae are also found in reptile faeces (Acanthamoeba, Naegleria, Hartmanella, Vahlkampfia or Echinamoeba sp.).

  12. Evolution of posterior lateral line development in fish and amphibians.

    Science.gov (United States)

    Pichon, Fabien; Ghysen, Alain

    2004-01-01

    The lateral line is a sensory system present in fish and amphibians. It is composed of discrete sense organs, the neuromasts, arranged on the head and body in species-specific patterns. The neuromasts are deposited by migrating primordia that originate from pre- and postotic placodes and follow defined pathways on the head and body. Here we examine the formation of the posterior lateral line (PLL), which extends rostrocaudally on the trunk and tail. In amphibians, the PLL neuromasts are deposited as a single wave from the head to the tip of the tail. In the zebrafish, however, the first wave of neuromast deposition forms but a rudimentary PLL, and several additional waves are needed to form the adult pattern. We show that the amphibian mode is also present in the sturgeon and therefore probably represents the primitive mode, whereas the zebrafish mode is highly conserved in several teleost species. A third mode is found in a subgroup of teleosts, the protacanthopterygians, and may represent a synapomorphy of this group. Altogether, the mode of formation of the embryonic PLL appears to have undergone remarkably few changes during the long history of anamniote evolution, even though large differences can be observed in the lateral line morphology of adult fishes.

  13. Independent evolution of the sexes promotes amphibian diversification.

    Science.gov (United States)

    De Lisle, Stephen P; Rowe, Locke

    2015-03-22

    Classic ecological theory predicts that the evolution of sexual dimorphism constrains diversification by limiting morphospace available for speciation. Alternatively, sexual selection may lead to the evolution of reproductive isolation and increased diversification. We test contrasting predictions of these hypotheses by examining the relationship between sexual dimorphism and diversification in amphibians. Our analysis shows that the evolution of sexual size dimorphism (SSD) is associated with increased diversification and speciation, contrary to the ecological theory. Further, this result is unlikely to be explained by traditional sexual selection models because variation in amphibian SSD is unlikely to be driven entirely by sexual selection. We suggest that relaxing a central assumption of classic ecological models-that the sexes share a common adaptive landscape-leads to the alternative hypothesis that independent evolution of the sexes may promote diversification. Once the constraints of sexual conflict are relaxed, the sexes can explore morphospace that would otherwise be inaccessible. Consistent with this novel hypothesis, the evolution of SSD in amphibians is associated with reduced current extinction threat status, and an historical reduction in extinction rate. Our work reconciles conflicting predictions from ecological and evolutionary theory and illustrates that the ability of the sexes to evolve independently is associated with a spectacular vertebrate radiation.

  14. Optimizing protection efforts for amphibian conservation in Mediterranean landscapes

    Science.gov (United States)

    García-Muñoz, Enrique; Ceacero, Francisco; Carretero, Miguel A.; Pedrajas-Pulido, Luis; Parra, Gema; Guerrero, Francisco

    2013-05-01

    Amphibians epitomize the modern biodiversity crisis, and attract great attention from the scientific community since a complex puzzle of factors has influence on their disappearance. However, these factors are multiple and spatially variable, and declining in each locality is due to a particular combination of causes. This study shows a suitable statistical procedure to determine threats to amphibian species in medium size administrative areas. For our study case, ten biological and ecological variables feasible to affect the survival of 15 amphibian species were categorized and reduced through Principal Component Analysis. The principal components extracted were related to ecological plasticity, reproductive potential, and specificity of breeding habitats. Finally, the factor scores of species were joined in a presence-absence matrix that gives us information to identify where and why conservation management are requires. In summary, this methodology provides the necessary information to maximize benefits of conservation measures in small areas by identifying which ecological factors need management efforts and where should we focus them on.

  15. Interventions for reducing extinction risk in chytridiomycosis-threatened amphibians.

    Science.gov (United States)

    Scheele, Ben C; Hunter, David A; Grogan, Laura F; Berger, Lee; Kolby, Jon E; McFadden, Michael S; Marantelli, Gerry; Skerratt, Lee F; Driscoll, Don A

    2014-10-01

    Wildlife diseases pose an increasing threat to biodiversity and are a major management challenge. A striking example of this threat is the emergence of chytridiomycosis. Despite diagnosis of chytridiomycosis as an important driver of global amphibian declines 15 years ago, researchers have yet to devise effective large-scale management responses other than biosecurity measures to mitigate disease spread and the establishment of disease-free captive assurance colonies prior to or during disease outbreaks. We examined the development of management actions that can be implemented after an epidemic in surviving populations. We developed a conceptual framework with clear interventions to guide experimental management and applied research so that further extinctions of amphibian species threatened by chytridiomycosis might be prevented. Within our framework, there are 2 management approaches: reducing Batrachochytrium dendrobatidis (the fungus that causes chytridiomycosis) in the environment or on amphibians and increasing the capacity of populations to persist despite increased mortality from disease. The latter approach emphasizes that mitigation does not necessarily need to focus on reducing disease-associated mortality. We propose promising management actions that can be implemented and tested based on current knowledge and that include habitat manipulation, antifungal treatments, animal translocation, bioaugmentation, head starting, and selection for resistance. Case studies where these strategies are being implemented will demonstrate their potential to save critically endangered species.

  16. Cardiac performance correlates of relative heart ventricle mass in amphibians.

    Science.gov (United States)

    Kluthe, Gregory J; Hillman, Stanley S

    2013-08-01

    This study used an in situ heart preparation to analyze the power output and stroke work of spontaneously beating hearts of four anurans (Rhinella marina, Lithobates catesbeianus, Xenopus laevis, Pyxicephalus edulis) and three urodeles (Necturus maculosus, Ambystoma tigrinum, Amphiuma tridactylum) that span a representative range of relative ventricle mass (RVM) found in amphibians. Previous research has documented that RVM correlates with dehydration tolerance and maximal aerobic capacity in amphibians. The power output (mW g(-1) ventricle mass) and stroke work (mJ g(-1) ventricle muscle mass) were independent of RVM and were indistinguishable from previously published results for fish and reptiles. RVM was significantly correlated with maximum power output (P max, mW kg(-1) body mass), stroke volume, cardiac output, afterload pressure (P O) at P max, and preload pressure (P I) at P max. P I at P max and P O at P max also correlated very closely with each other. The increases in both P I and P O at maximal power outputs in large hearts suggest that concomitant increases in blood volume and/or increased modulation of vascular compliance either anatomically or via sympathetic tone on the venous vasculature would be necessary to achieve P max in vivo. Hypotheses for variation in RVM and its concomitant increased P max in amphibians are developed.

  17. Nomenclatural notes on living and fossil amphibians

    Directory of Open Access Journals (Sweden)

    Martín, C.

    2012-06-01

    Full Text Available A review of extinct and living amphibians known from fossils (Allocaudata, Anura and Caudata has revealed several cases that require nomenclatural changes in order to stabilize the taxonomy of the group. Nomenclatural changes include homonym replacements, corrections of spelling variants and authorships, name availabilities, and in particular, the proposal of new combinations. These changes will allow the incorporation of some palaeontological taxa to the current evolutionary models of relationship of modern forms based on molecular phylogenies. Rana cadurcorum for Rana plicata Filhol, 1877, Rana auscitana for Rana pygmaea Lartet, 1851, and Rana sendoa for Rana robusta Brunner, 1956. Anchylorana Taylor, 1942 is considered a new synonym of Lithobates Fitzinger, 1843. New combinations proposed are: Anaxyrus defensor for Bufo defensor Meylan, 2005; Anaxyrus hibbardi for Bufo hibbardi Taylor, 1937; Anaxyrus pliocompactilis for Bufo pliocompactilis Wilson, 1968; Anaxyrus repentinus for Bufo repentinus Tihen, 1962; Anaxyrus rexroadensis for Bufo rexroadensis Tihen, 1962; Anaxyrus spongifrons for Bufo spongifrons Tihen, 1962; Anaxyrus suspectus for Bufo suspectus Tihen, 1962; Anaxyrus tiheni for Bufo tiheni Auffenberg, 1957; Anaxyrus valentinensis for Bufo valentinensis Estes et Tihen, 1964; Ichthyosaura wintershofi for Triturus wintershofi Lunau, 1950; Incilius praevius for Bufo praevius Tihen, 1951; Lithobates bucella for Rana bucella Holman, 1965; Lithobates dubitus for Anchylorana dubita Taylor, 1942; Lithobates fayeae for Rana fayeae Taylor, 1942; Lithobates miocenicus for Rana miocenica Holman, 1965; Lithobates moorei for Anchylorana moorei Taylor, 1942; Lithobates parvissimus for Rana parvissima

  18. Amphibian and reptile declines over 35 years at La Selva, Costa Rica.

    Science.gov (United States)

    Whitfield, Steven M; Bell, Kristen E; Philippi, Thomas; Sasa, Mahmood; Bolaños, Federico; Chaves, Gerardo; Savage, Jay M; Donnelly, Maureen A

    2007-05-15

    Amphibians stand at the forefront of a global biodiversity crisis. More than one-third of amphibian species are globally threatened, and over 120 species have likely suffered global extinction since 1980. Most alarmingly, many rapid declines and extinctions are occurring in pristine sites lacking obvious adverse effects of human activities. The causes of these "enigmatic" declines remain highly contested. Still, lack of long-term data on amphibian populations severely limits our understanding of the distribution of amphibian declines, and therefore the ultimate causes of these declines. Here, we identify a systematic community-wide decline in populations of terrestrial amphibians at La Selva Biological Station, a protected old-growth lowland rainforest in lower Central America. We use data collected over 35 years to show that population density of all species of terrestrial amphibians has declined by approximately 75% since 1970, and we show identical trends for all species of common reptiles. The trends we identify are neither consistent with recent emergence of chytridiomycosis nor the climate-linked epidemic hypothesis, two leading putative causes of enigmatic amphibian declines. Instead, our data suggest that declines are due to climate-driven reductions in the quantity of standing leaf litter, a critical microhabitat for amphibians and reptiles in this assemblage. Our results raise further concerns about the global persistence of amphibian populations by identifying widespread declines in species and habitats that are not currently recognized as susceptible to such risks.

  19. Amphibians and disease: Implications for conservation in the Greater Yellowstone Ecosystem

    Science.gov (United States)

    Corn, P.S.

    2007-01-01

    The decline of amphibian populations is a world-wide phenomenon that has received increasing attention since about 1990. In 2004, the World Conservation Union’s global amphibian assessment concluded that 48% of the world’s 5,743 described amphibian species were in decline, with 32% considered threatened (Stuart et al. 2004). Amphibian declines are a significant issue in the western United States, where all native species of frogs in the genus Rana and many toads in the genus Bufo are at risk, particularly those that inhabit mountainous areas (Corn 2003a,b; Bradford 2005).

  20. Restored agricultural wetlands in Central Iowa: habitat quality and amphibian response

    Science.gov (United States)

    Pierce, Clay; Rebecca A. Reeves,; Smalling, Kelly; Klaver, Robert W.; Vandever, Mark; Battaglin, William A.; Muths, Erin L.

    2016-01-01

    Amphibians are declining throughout the United States and worldwide due, partly, to habitat loss. Conservation practices on the landscape restore wetlands to denitrify tile drainage effluent and restore ecosystem services. Understanding how water quality, hydroperiod, predation, and disease affect amphibians in restored wetlands is central to maintaining healthy amphibian populations in the region. We examined the quality of amphibian habitat in restored wetlands relative to reference wetlands by comparing species richness, developmental stress, and adult leopard frog (Lithobates pipiens) survival probabilities to a suite of environmental metrics. Although measured habitat variables differed between restored and reference wetlands, differences appeared to have sub-lethal rather than lethal effects on resident amphibian populations. There were few differences in amphibian species richness and no difference in estimated survival probabilities between wetland types. Restored wetlands had more nitrate and alkaline pH, longer hydroperiods, and were deeper, whereas reference wetlands had more amphibian chytrid fungus zoospores in water samples and resident amphibians exhibited increased developmental stress. Restored and reference wetlands are both important components of the landscape in central Iowa and maintaining a complex of fish-free wetlands with a variety of hydroperiods will likely contribute to the persistence of amphibians in this landscape.

  1. Immunological assessment of mice hyperimmunized with native and Cobalt-60-irradiated Bothrops venoms

    Directory of Open Access Journals (Sweden)

    R. S. Ferreira Junior

    2005-12-01

    Full Text Available ELISA was used to evaluate, accompany, and compare the humoral immune response of Swiss mice during hyperimmunization with native and Cobalt-60-irradiated (60Co venoms of Bothrops jararaca, Bothrops jararacussu and Bothrops moojeni. Potency and neutralization were evaluated by in vitro challenges. After hyperimmunization, immunity was observed by in vivo challenge, and the side effects were assessed. The animals immunization with one LD50 of each venom occurred on days 1, 15, 21, 30, and 45, when blood samples were collected; challenges happened on the 60th day. Results showed that ELISA was efficient in evaluating, accompanying and comparing mouse immune response during hyperimmunization. Serum titers produced with natural venom were similar to those produced with irradiated venom. Immunogenic capacity was maintained after 60Co-irradiation. The sera produced with native venom showed neutralizing potency and capacity similar to those of the sera produced with irradiated venom. All antibodies were able to neutralize five LD50 from these venoms. Clinical alterations were minimum during hyperimmunization with irradiated venom, however, necrosis and death occurred in animals inoculated with native venom.

  2. Venoms of Heteropteran Insects: A Treasure Trove of Diverse Pharmacological Toolkits

    Directory of Open Access Journals (Sweden)

    Andrew A. Walker

    2016-02-01

    Full Text Available The piercing-sucking mouthparts of the true bugs (Insecta: Hemiptera: Heteroptera have allowed diversification from a plant-feeding ancestor into a wide range of trophic strategies that include predation and blood-feeding. Crucial to the success of each of these strategies is the injection of venom. Here we review the current state of knowledge with regard to heteropteran venoms. Predaceous species produce venoms that induce rapid paralysis and liquefaction. These venoms are powerfully insecticidal, and may cause paralysis or death when injected into vertebrates. Disulfide-rich peptides, bioactive phospholipids, small molecules such as N,N-dimethylaniline and 1,2,5-trithiepane, and toxic enzymes such as phospholipase A2, have been reported in predatory venoms. However, the detailed composition and molecular targets of predatory venoms are largely unknown. In contrast, recent research into blood-feeding heteropterans has revealed the structure and function of many protein and non-protein components that facilitate acquisition of blood meals. Blood-feeding venoms lack paralytic or liquefying activity but instead are cocktails of pharmacological modulators that disable the host haemostatic systems simultaneously at multiple points. The multiple ways venom is used by heteropterans suggests that further study will reveal heteropteran venom components with a wide range of bioactivities that may be recruited for use as bioinsecticides, human therapeutics, and pharmacological tools.

  3. Venoms of Heteropteran Insects: A Treasure Trove of Diverse Pharmacological Toolkits.

    Science.gov (United States)

    Walker, Andrew A; Weirauch, Christiane; Fry, Bryan G; King, Glenn F

    2016-02-12

    The piercing-sucking mouthparts of the true bugs (Insecta: Hemiptera: Heteroptera) have allowed diversification from a plant-feeding ancestor into a wide range of trophic strategies that include predation and blood-feeding. Crucial to the success of each of these strategies is the injection of venom. Here we review the current state of knowledge with regard to heteropteran venoms. Predaceous species produce venoms that induce rapid paralysis and liquefaction. These venoms are powerfully insecticidal, and may cause paralysis or death when injected into vertebrates. Disulfide-rich peptides, bioactive phospholipids, small molecules such as N,N-dimethylaniline and 1,2,5-trithiepane, and toxic enzymes such as phospholipase A2, have been reported in predatory venoms. However, the detailed composition and molecular targets of predatory venoms are largely unknown. In contrast, recent research into blood-feeding heteropterans has revealed the structure and function of many protein and non-protein components that facilitate acquisition of blood meals. Blood-feeding venoms lack paralytic or liquefying activity but instead are cocktails of pharmacological modulators that disable the host haemostatic systems simultaneously at multiple points. The multiple ways venom is used by heteropterans suggests that further study will reveal heteropteran venom components with a wide range of bioactivities that may be recruited for use as bioinsecticides, human therapeutics, and pharmacological tools.

  4. Biological and Enzymatic Characterization of Proteases from Crude Venom of the Ant Odontomachus bauri

    Directory of Open Access Journals (Sweden)

    Mariana Ferreira Silva

    2015-11-01

    Full Text Available Hymenoptera venoms constitute an interesting source of natural toxins that may lead to the development of novel therapeutic agents. The present study investigated the enzymatic and biological characteristics of the crude venom of the ant Odontomachus bauri. Its crude venom presents several protein bands, with higher staining for six proteins with gelatinolytic activity (17, 20, 26, 29, 43 and 48 kDa. The crude venom showed high proteolytic activity on azocasein at optimal pH 8.0 and 37 °C. In the presence of protease inhibitors as aprotinin, leupeptin and EDTA, the azocaseinolytic activity was reduced by 45%, 29% and 9%, respectively, suggesting that the enzymes present in the crude venom belong to the three classes of proteases, with the serine proteases in greater intensity. The crude venom degraded the fibrinogen α-chain faster than the β-chain, while the fibrinogen γ-chain remained unchanged. In biological assays, O. bauri venom showed hemolytic and coagulant activity in vitro, and defibrinating activity in vivo. In addition, the venom showed antimicrobial activity against Staphylococcus aureus and Escherichia coli as well as antiparasitic activity on Toxoplasma gondii infection in vitro. In that sense, this study sheds perspectives for pharmacological applications of O. bauri venom enzymes.

  5. Biological and Enzymatic Characterization of Proteases from Crude Venom of the Ant Odontomachus bauri.

    Science.gov (United States)

    Silva, Mariana Ferreira; Mota, Caroline Martins; Miranda, Vanessa dos Santos; Cunha, Amanda de Oliveira; Silva, Maraísa Cristina; Naves, Karinne Spirandelli Carvalho; de Oliveira, Fábio; Silva, Deise Aparecida de Oliveira; Mineo, Tiago Wilson Patriarca; Santiago, Fernanda Maria

    2015-11-30

    Hymenoptera venoms constitute an interesting source of natural toxins that may lead to the development of novel therapeutic agents. The present study investigated the enzymatic and biological characteristics of the crude venom of the ant Odontomachus bauri. Its crude venom presents several protein bands, with higher staining for six proteins with gelatinolytic activity (17, 20, 26, 29, 43 and 48 kDa). The crude venom showed high proteolytic activity on azocasein at optimal pH 8.0 and 37 °C. In the presence of protease inhibitors as aprotinin, leupeptin and EDTA, the azocaseinolytic activity was reduced by 45%, 29% and 9%, respectively, suggesting that the enzymes present in the crude venom belong to the three classes of proteases, with the serine proteases in greater intensity. The crude venom degraded the fibrinogen α-chain faster than the β-chain, while the fibrinogen γ-chain remained unchanged. In biological assays, O. bauri venom showed hemolytic and coagulant activity in vitro, and defibrinating activity in vivo. In addition, the venom showed antimicrobial activity against Staphylococcus aureus and Escherichia coli as well as antiparasitic activity on Toxoplasma gondii infection in vitro. In that sense, this study sheds perspectives for pharmacological applications of O. bauri venom enzymes.

  6. Biochemical and hematological study of goats envenomed with natural and 60Co-irradiated bothropic venom

    Energy Technology Data Exchange (ETDEWEB)

    Lucas de Oliveira, P.C.; Madruga, R.A.; Barbosa, N.P.U. [Uberaba School of Veterinary Medicine (UNIUBE), MG (Brazil)]. E-mail: pedrolucaso@uol.com.br; Sakate, M. [UNESP, Botucatu, SP (Brazil). School of Veterinary Medicine and Animal Husbandry

    2007-07-01

    Venoms from snakes of the Bothrops genus are proteolytic, coagulant, hemorrhagic and nephrotoxic, causing edema, necrosis, hemorrhage and intense pain at the bite site, besides systemic alterations. Many adjuvants have been added to the venom used in the sensitization of antiserum-producer animals to increase antigenic induction and reduce the envenomation pathological effects. Gamma radiation from {sup 60}Co has been used as an attenuating agent of the venoms toxic properties. The main objective was to study, comparatively, clinical and laboratory aspects of goats inoculated with bothropic (Bothrops jararaca) venom, natural and irradiated from a {sup 60}Co source. Twelve goats were divided into two groups of six animals: GINV, inoculated with 0.5 mg/kg of natural venom; and GIIV, inoculated with 0.5 mg/kg of irradiated venom. Blood samples were collected immediately before and one, two, seven, and thirty days after venom injection. Local lesions were daily evaluated. The following exams were carried out: blood tests; biochemical tests of urea, creatinine, creatine kinase, aspartate amino-transferase and alanine amino-transferase; clotting time; platelets count; and total serum immunoglobulin measurement. In the conditions of the present experiment, irradiated venom was less aggressive and more immunogenic than natural venom. (author)

  7. Biochemical and hematological study of goats envenomed with natural and 60Co-irradiated bothropic venom

    Directory of Open Access Journals (Sweden)

    P. C. Lucas de Oliveira

    2007-01-01

    Full Text Available Venoms from snakes of the Bothrops genus are proteolytic, coagulant, hemorrhagic and nephrotoxic, causing edema, necrosis, hemorrhage and intense pain at the bite site, besides systemic alterations. Many adjuvants have been added to the venom used in the sensitization of antiserum-producer animals to increase antigenic induction and reduce the envenomation pathological effects. Gamma radiation from 60Co has been used as an attenuating agent of the venoms toxic properties. The main objective was to study, comparatively, clinical and laboratory aspects of goats inoculated with bothropic (Bothrops jararaca venom, natural and irradiated from a 60Co source. Twelve goats were divided into two groups of six animals: GINV, inoculated with 0.5mg/kg of natural venom; and GIIV, inoculated with 0.5mg/kg of irradiated venom. Blood samples were collected immediately before and one, two, seven, and thirty days after venom injection. Local lesions were daily evaluated. The following exams were carried out: blood tests; biochemical tests of urea, creatinine, creatine kinase (CK, aspartate amino-transferase (AST and alanine amino-transferase (ALT; clotting time; platelets count; and total serum immunoglobulin measurement. In the conditions of the present experiment, irradiated venom was less aggressive and more immunogenic than natural venom.

  8. Defensins and the convergent evolution of platypus and reptile venom genes.

    Science.gov (United States)

    Whittington, Camilla M; Papenfuss, Anthony T; Bansal, Paramjit; Torres, Allan M; Wong, Emily S W; Deakin, Janine E; Graves, Tina; Alsop, Amber; Schatzkamer, Kyriena; Kremitzki, Colin; Ponting, Chris P; Temple-Smith, Peter; Warren, Wesley C; Kuchel, Philip W; Belov, Katherine

    2008-06-01

    When the platypus (Ornithorhynchus anatinus) was first discovered, it was thought to be a taxidermist's hoax, as it has a blend of mammalian and reptilian features. It is a most remarkable mammal, not only because it lays eggs but also because it is venomous. Rather than delivering venom through a bite, as do snakes and shrews, male platypuses have venomous spurs on each hind leg. The platypus genome sequence provides a unique opportunity to unravel the evolutionary history of many of these interesting features. While searching the platypus genome for the sequences of antimicrobial defensin genes, we identified three Ornithorhynchus venom defensin-like peptide (OvDLP) genes, which produce the major components of platypus venom. We show that gene duplication and subsequent functional diversification of beta-defensins gave rise to these platypus OvDLPs. The OvDLP genes are located adjacent to the beta-defensins and share similar gene organization and peptide structures. Intriguingly, some species of snakes and lizards also produce venoms containing similar molecules called crotamines and crotamine-like peptides. This led us to trace the evolutionary origins of other components of platypus and reptile venom. Here we show that several venom components have evolved separately in the platypus and reptiles. Convergent evolution has repeatedly selected genes coding for proteins containing specific structural motifs as templates for venom molecules.

  9. Cloning and characterisation of novel cystatins from elapid snake venom glands.

    Science.gov (United States)

    Richards, Renée; St Pierre, Liam; Trabi, Manuela; Johnson, Lambro A; de Jersey, John; Masci, Paul P; Lavin, Martin F

    2011-04-01

    Snake venoms contain a complex mixture of polypeptides that modulate prey homeostatic mechanisms through highly specific and targeted interactions. In this study we have identified and characterised cystatin-like cysteine-protease inhibitors from elapid snake venoms for the first time. Novel cystatin sequences were cloned from 12 of 13 elapid snake venom glands and the protein was detected, albeit at very low levels, in a total of 22 venoms. One highly conserved isoform, which displayed close sequence identity with family 2 cystatins, was detected in each elapid snake. Crude Austrelaps superbus (Australian lowland copperhead) snake venom inhibited papain, and a recombinant form of A. superbus cystatin inhibited cathepsin L ≅ papain > cathepsin B, with no inhibition observed for calpain or legumain. While snake venom cystatins have truncated N-termini, sequence alignment and structural modelling suggested that the evolutionarily conserved Gly-11 of family 2 cystatins, essential for cysteine protease inhibition, is conserved in snake venom cystatins as Gly-3. This was confirmed by mutagenesis at the Gly-3 site, which increased the dissociation constant for papain by 10(4)-fold. These data demonstrate that elapid snake venom cystatins are novel members of the type 2 family. The widespread, low level expression of type 2 cystatins in snake venom, as well as the presence of only one highly conserved isoform in each species, imply essential housekeeping or regulatory roles for these proteins.

  10. A Study on the Effects of Bee Venom Aqua-Acupuncture on Writhing Reflex

    Directory of Open Access Journals (Sweden)

    Jeong Sun-Hee

    2000-07-01

    Full Text Available Introduction:In spite of the use of Bee Venom aqua-acupuncture in the clinics, the scientific evaluation on effects is not enough. Bee Venom aqua-acupuncture is used according to the stimulation of acupuncture point and the chemical effects of Bee Venom. The aims of this study is to investigate the analgegic effects of the Bee Venom aqua-acupuncture, through the change of writhing reflex Materials and Methods:Pain animal model was used acetic acid method. The changes of writhing reflex of the mice which were derived pain by injecting acetic acid into the abdomen, after stimulating Bee Venom aqua-acupuncture on Chungwan(CV12 and non acupuncture point on the backside were measured. Results:1. It showed that the writhing reflex were appeared on the groups which injected acetic acid only, and saline-acetic acid group(sample I, but not on the group bee venom-saline group(sample II. 2. The change of writhing reflex by Chungwan(CV12 Bee Venom aqua-acupuncture showed significant decrease in the order of Chungwan(CV12 Bee Venom aqua-acupuncture group III(2.5×10-3g/kg, II(2.5×10-4g/kg, and I(2.5×10-5g/kg, compared with control group. There were significant decrease of number of writhing reflex in 5~10, 10~15 and 15~20 minutes intervals of Chung wan(CV12 Bee Venom aqua-acupuncture group I, and in 0~5, 5~10, 10~15 and 15~20 minutes intervals of II and III, compared with control group. 3. The change of writhing reflex by non acupuncture point Bee Venom aqua-acupuncture showed significant decrease in the 0~5 and 5~10 minutes intervals and the total number of writhing reflex in 2.5×10-4g/kg group, compared with control group 4. The effects of writhing reflex of Chungwan(CV12 Bee Venom aqua-acupuncture group showed significant decrease, compared with non acupuncture point Bee Venom aqua-acupuncture group. Conclusion:This study shows that the Bee Venom aqua-acupuncture on Chungwan(CV12 decreases the numbers of writhing reflex. As the

  11. Variations in Loxosceles spider venom composition and toxicity contribute to the severity of envenomation.

    Science.gov (United States)

    de Oliveira, Kátia C; Gonçalves de Andrade, Rute M; Piazza, Roxane M F; Ferreira, Jorge M C; van den Berg, C W; Tambourgi, Denise V

    2005-03-15

    Envenomation by Loxosceles spiders causes two main clinical manifestations: cutaneous and systemic loxoscelism. The factors contributing to the severity of loxoscelism are not fully understood. We have analysed biochemical and toxicity variations in venom of L. laeta and L. intermedia, with the aim to find a correlation with the seriousness of loxoscelism. Differences in expression of proteins, glycoproteins and sphingomyelinase activity were observed between venom from male and female spiders and between venom from the two species. These differences were reflected in the toxicity of the venoms including the capacity to induce complement-dependent haemolysis, dermonecrosis and lethality. Comparative analysis of gender and species, showed that these biological activities were more prominent in venom from female spiders, especially from L. laeta. Antiserum raised against venom from females L. laeta spiders had the highest efficacy in neutralizing venoms of males and females of both species. These results indicate that the severity of loxoscelism depends, at least partially, on the species and sex of the spider and suggest that for accidents involving L. laeta an specific serum therapy is necessary. Furthermore, it emphasizes the efficacy of the antiserum produced against L. laeta female venom in neutralizing Loxosceles venoms from different species and gender.

  12. Characterization of Three Venom Peptides from the Spitting Spider Scytodes thoracica

    Science.gov (United States)

    Ariki, Nathanial K.; Muñoz, Lisa E.; Armitage, Elizabeth L.; Goodstein, Francesca R.; George, Kathryn G.; Smith, Vanessa L.; Vetter, Irina; Herzig, Volker; King, Glenn F.; Loening, Nikolaus M.

    2016-01-01

    We present the solution-state NMR structures and preliminary functional characterizations of three venom peptides identified from the spitting spider Scytodes thoracica. Despite little sequence identity to other venom peptides, structural characterization reveals that these peptides contain an inhibitor cystine knot motif common to many venom peptides. These are the first structures for any peptide or protein from spiders of the Scytodidae family. Many venom peptides target neuronal ion channels or receptors. However, we have not been able to determine the target of these Scytodes peptides so we can only state with certainty the channels and receptors that they do not target. PMID:27227898

  13. Inflammatory mediators generated at the site of inoculation of Loxosceles gaucho spider venom.

    Science.gov (United States)

    Barbaro, Katia C; Lira, Marcela S; Araújo, Claudia A; Pareja-Santos, Alessandra; Távora, Bianca C L F; Prezotto-Neto, José Pedro; Kimura, Louise F; Lima, Carla; Lopes-Ferreira, Mônica; Santoro, Marcelo L

    2010-11-01

    Patients bitten by Loxosceles spiders generally manifest marked local inflammatory reaction and dermonecrosis. This report evaluated edema formation, leukocyte infiltration and release of inflammatory mediators at the injection site of Loxosceles gaucho venom. BALB/c mice were i.d. injected with venom and thereafter paws were disrupted and homogenized to obtain differential counts of migrated cells, as well to assay the levels of cytokines, chemokines and lipid mediators. Increased footpad thickness was detected as soon as 30 min after venom injection, and 24h later was similar to that of the control group. Loxosceles venom mildly augmented the recruitment of leukocytes to the footpad in comparison with PBS-injected mice. Moreover, it stimulated the release of IL-6, MCP-1 and KC at 2 and 24h after venom injection. In addition, higher levels of PGE(2) were detected 30 min after venom injection in comparison with control group. However, the venom failed to increase levels of IL-1 beta, TNF-alpha, TXB(2) and LTB(4). Our results demonstrate that L. gaucho venom evokes an early complex inflammatory reaction, stimulating the secretion of pro-inflammatory cytokines and lipid mediators (PGE(2)), and recruiting leukocytes to the footpad which contribute to the local reaction induced by L. gaucho venom.

  14. Characterization of Three Venom Peptides from the Spitting Spider Scytodes thoracica.

    Directory of Open Access Journals (Sweden)

    Nathanial K Ariki

    Full Text Available We present the solution-state NMR structures and preliminary functional characterizations of three venom peptides identified from the spitting spider Scytodes thoracica. Despite little sequence identity to other venom peptides, structural characterization reveals that these peptides contain an inhibitor cystine knot motif common to many venom peptides. These are the first structures for any peptide or protein from spiders of the Scytodidae family. Many venom peptides target neuronal ion channels or receptors. However, we have not been able to determine the target of these Scytodes peptides so we can only state with certainty the channels and receptors that they do not target.

  15. Biological and Pathological Studies of Rosmarinic Acid as an Inhibitor of Hemorrhagic Trimeresurus flavoviridis (habu Venom

    Directory of Open Access Journals (Sweden)

    Masatake Niwa

    2010-10-01

    Full Text Available In our previous report, rosmarinic acid (RA was revealed to be an antidote active compound in Argusia argentea (family: Boraginaceae. The plant is locally used in Okinawa in Japan as an antidote for poisoning from snake venom, Trimeresurus flavoviridis (habu. This article presents mechanistic evidence of RA’s neutralization of the hemorrhagic effects of snake venom. Anti-hemorrhagic activity was assayed by using several kinds of snake venom. Inhibition against fibrinogen hydrolytic and collagen hydrolytic activities of T. flavoviridis venom were examined by SDS-PAGE. A histopathological study was done by microscopy after administration of venom in the presence or absence of RA. RA was found to markedly neutralize venom-induced hemorrhage, fibrinogenolysis, cytotoxicity and digestion of type IV collagen activity. Moreover, RA inhibited both hemorrhage and neutrophil infiltrations caused by T. flavoviridis venom in pathology sections. These results demonstrate that RA inhibited most of the hemorrhage effects of venom. These findings indicate that rosmarinic acid can be expected to provide therapeutic benefits in neutralization of snake venom accompanied by heat stability.

  16. Insects as biological models to assay spider and scorpion venom toxicity

    Directory of Open Access Journals (Sweden)

    M. F. Manzoli-Palma

    2003-01-01

    Full Text Available This study was undertaken to develop an experimental protocol using insects as biological models to assay venom toxicity of the following spiders Loxosceles gaucho, Phoneutria nigriventer, Nephilengys cruentata and Tityus serrulatus scorpion. Three different insect species were bioassayed: Apis mellifera (Hymenoptera, Grillus assimilis (Orthoptera, and Diatraea saccharalis (Lepidoptera. Venoms were injected into the hemocele of insects with a microsyringe at concentrations that caused dose/weight-dependent effects; doses causing either paralysis (ED50 or death (LD50 were recorded for each venom and insect test-species. T. serrulatus and L. gaucho venoms were lethal to all tested species, while P. nigriventer venom caused paralysis and death, and N. cruentata venom caused only paralysis at the doses assayed. A comparison between the insect test species described above revealed that A. mellifera was highly sensitive to all venoms tested; even a tiny amount of N. cruentata non-lethal venom caused a change in the walking pattern leading to transient paralysis. D. saccharalis larvae were very resistant to all four venoms.

  17. Endocannabinoids affect the reproductive functions in teleosts and amphibians.

    Science.gov (United States)

    Cottone, E; Guastalla, A; Mackie, K; Franzoni, M F

    2008-04-16

    Following the discovery in the brain of the bonyfish Fugu rubripes of two genes encoding for type 1 cannabinoid receptors (CB1A and CB1B), investigations on the phylogeny of these receptors have indicated that the cannabinergic system is highly conserved. Among the multiple functions modulated by cannabinoids/endocannabinoids through the CB1 receptors one of the more investigated is the mammalian reproduction. Therefore, since studies performed in animal models other than mammals might provide further insight into the biology of these signalling molecules, the major aim of the present paper was to review the comparative data pointing toward the endocannabinoid involvement in the reproductive control of non-mammalian vertebrates, namely bonyfish and amphibians. The expression and distribution of CB1 receptors were investigated in the CNS and gonads of two teleosts, Pelvicachromis pulcher and Carassius auratus as well as in the anuran amphibians Xenopus laevis and Rana esculenta. In general the large diffusion of neurons targeted by cannabinoids in both fish and amphibian forebrain indicate endocannabinoids as pivotal local messengers in several neural circuits involved in either sensory integrative activities, like the olfactory processes (in amphibians) and food response (in bonyfish), or neuroendocrine machinery (in both). By using immunohistochemistry for CB1 and GnRH-I, the codistribution of the two signalling molecules was found in the fish basal telencephalon and preoptic area, which are key centers for gonadotropic regulation in all vertebrates. A similar topographical codistribution was observed also in the septum of the telencephalon in Rana esculenta and Xenopus laevis. Interestingly, the double standard immunofluorescence on the same brain section, aided with a laser confocal microscope, showed that in anurans a subset of GnRH-I neurons exhibited also the CB1 immunostaining. The fact that CB1-LI-IR was found indeed in the FSH gonadotrophs of the Xenopus

  18. Anti-scorpion venom activity of Andrographis paniculata: A combined and comparative study with anti-scorpion serum in mice

    Directory of Open Access Journals (Sweden)

    Ranjana S Kale

    2013-01-01

    Conclusions: Present study demonstrates that, both plant extract and ASV have their own scorpion venom neutralising ability in vivo and in vitro, but their combination is most effective in venom neutralizing ability.

  19. Firing the Sting: Chemically Induced Discharge of Cnidae Reveals Novel Proteins and Peptides from Box Jellyfish (Chironex fleckeri) Venom

    OpenAIRE

    2015-01-01

    Cnidarian venom research has lagged behind other toxinological fields due to technical difficulties in recovery of the complex venom from the microscopic nematocysts. Here we report a newly developed rapid, repeatable and cost effective technique of venom preparation, using ethanol to induce nematocyst discharge and to recover venom contents in one step. Our model species was the Australian box jellyfish (Chironex fleckeri), which has a notable impact on public health. By utilizing scanning e...

  20. Cubozoan Venom-Induced Cardiovascular Collapse Is Caused by Hyperkalemia and Prevented by Zinc Gluconate in Mice

    OpenAIRE

    2012-01-01

    Chironex fleckeri (Australian box jellyfish) stings can cause acute cardiovascular collapse and death. We developed methods to recover venom with high specific activity, and evaluated the effects of both total venom and constituent porins at doses equivalent to lethal envenomation. Marked potassium release occurred within 5 min and hemolysis within 20 min in human red blood cells (RBC) exposed to venom or purified venom porin. Electron microscopy revealed abundant ~12-nm transmembrane pores i...

  1. The Effects of a Chactoid Scorpion Venom and Its Purified Toxins on Rat Blood Pressure and Mast Cells Histamine Release

    OpenAIRE

    2013-01-01

    The effect of the venom of the Chactoid family of scorpions on blood pressure was scantly investigated and was addressed in the present study using the venom of the Israeli scorpion, Scorpio maurus palmatus. Blood pressure in rats was monitored via cannulated femoral artery, while venom and toxins were introduced into femoral vein. Venom injection elicited a biphasic effect, expressed first by a fast and transient hypotensive response, which lasted up to 10 min, followed by a hypertensive res...

  2. Evaluation of different glycoforms of honeybee venom major allergen phospholipase A2 (Api m 1) produced in insect cells

    DEFF Research Database (Denmark)

    Blank, Simon; Seismann, Henning; Plum, Melanie;

    2011-01-01

    Allergic reactions to hymenoptera stings are one of the major reasons for IgE-mediated anaphylaxis. However, proper diagnosis using venom extracts is severely affected by molecular cross-reactivity. In this study recombinant honeybee venom major allergen phospholipase A2 (Api m 1) was produced......-derived recombinant Api m 1 with defined CCD phenotypes might provide further insights into hymenoptera venom IgE reactivities and contribute to an improved diagnosis of hymenoptera venom allergy....

  3. Acute oral toxicity of chemicals in terrestrial life stages of amphibians: Comparisons to birds and mammals.

    Science.gov (United States)

    Crane, Mark; Finnegan, Meaghean; Weltje, Lennart; Kosmala-Grzechnik, Sylwia; Gross, Melanie; Wheeler, James R

    2016-10-01

    Amphibians are currently the most threatened and rapidly declining group of vertebrates and this has raised concerns about their potential sensitivity and exposure to plant protection products and other chemicals. Current environmental risk assessment procedures rely on surrogate species (e.g. fish and birds) to cover the risk to aquatic and terrestrial life stages of amphibians, respectively. Whilst a recent meta-analysis has shown that in most cases amphibian aquatic life stages are less sensitive to chemicals than fish, little research has been conducted on the comparative sensitivity of terrestrial amphibian life stages. Therefore, in this paper we address the questions "What is the relative sensitivity of terrestrial amphibian life stages to acute chemical oral exposure when compared with mammals and birds?" and "Are there correlations between oral toxicity data for amphibians and data for mammals or birds?" Identifying a relationship between these data may help to avoid additional vertebrate testing. Acute oral amphibian toxicity data collected from the scientific literature and ecotoxicological databases were compared with toxicity data for mammals and birds. Toxicity data for terrestrial amphibian life stages are generally sparse, as noted in previous reviews. Single-dose oral toxicity data for terrestrial amphibian life stages were available for 26 chemicals and these were positively correlated with LD50 values for mammals, while no correlation was found for birds. Further, the data suggest that oral toxicity to terrestrial amphibian life stages is similar to or lower than that for mammals and birds, with a few exceptions. Thus, mammals or birds are considered adequate toxicity surrogates for use in the assessment of the oral exposure route in amphibians. However, there is a need for further data on a wider range of chemicals to explore the wider applicability of the current analyses and recommendations.

  4. Comparative acute and chronic sensitivity of fish and amphibians: a critical review of data.

    Science.gov (United States)

    Weltje, Lennart; Simpson, Peter; Gross, Melanie; Crane, Mark; Wheeler, James R

    2013-04-01

    The relative sensitivity of amphibians to chemicals in the environment, including plant protection product active substances, is the subject of ongoing scientific debate. The objective of this study was to compare systematically the relative sensitivity of amphibians and fish to chemicals. Acute and chronic toxicity data were obtained from the U.S. Environmental Protection Agency (U.S. EPA) ECOTOX database and were supplemented with data from the scientific and regulatory literature. The overall outcome is that fish and amphibian toxicity data are highly correlated and that fish are more sensitive (both acute and chronic) than amphibians. In terms of acute sensitivity, amphibians were between 10- and 100-fold more sensitive than fish for only four of 55 chemicals and more than 100-fold more sensitive for only two chemicals. However, a detailed inspection of these cases showed a similar acute sensitivity of fish and amphibians. Chronic toxicity data for fish were available for 52 chemicals. Amphibians were between 10- and 100-fold more sensitive than fish for only two substances (carbaryl and dexamethasone) and greater than 100-fold more sensitive for only a single chemical (sodium perchlorate). The comparison for carbaryl was subsequently determined to be unreliable and that for sodium perchlorate is a potential artifact of the exposure medium. Only a substance such as dexamethasone, which interferes with a specific aspect of amphibian metamorphosis, might not be detected using fish tests. However, several other compounds known to influence amphibian metamorphosis were included in the analysis, and these did not affect amphibians disproportionately. These analyses suggest that additional amphibian testing is not necessary during chemical risk assessment.

  5. North Cascades National Park Service Complex Natural Resource Preservation Program Amphibian Inventory Big Beaver Watershed 1996 - Progress Report

    Data.gov (United States)

    Oak Ridge National Laboratory — The 1996 amphibian inventory in North Cascades National Park Service Complex Big Beaver watershed is part of a four year program to inventory amphibians in Pacific...

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

    Science.gov (United States)

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

    1998-05-01

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

  7. Techniques applicable for purifying Chironex fleckeri (box-jellyfish) venom.

    Science.gov (United States)

    Othman, I; Burnett, J W

    1990-01-01

    A survey of several techniques to isolate a purified lethal factor from the tentacles of Chironex fleckeri was completed. Heterologous band patterns were obtained from specific eluates after gel filtration, ion exchange, immunoaffinity and hydrophobic chromatography. SDS-PAGE revealed a dense band at 24,000 mol. wt in many of these fractions. Isoelectric focusing of the crude venom resulted in considerable loss of activity but indicated significant purification in the fractions having a pI of 5.2-6.8. These fractions were also immunologically active against sera from a convalescing post-evenomation patient. The primary difficulties encountered in jellyfish venom purification are the lack of stability and the tendency of the active toxins to adhere to each other and to various support matrices.

  8. Scorpion venom peptides with no disulfide bridges: a review.

    Science.gov (United States)

    Almaaytah, Ammar; Albalas, Qosay

    2014-01-01

    Scorpion venoms are rich sources of biologically active peptides that are classified into disulfide-bridged peptides (DBPs) and non-disulfide-bridged peptides (NDBPs). DBPs are the main scorpion venom components responsible for the neurotoxic effects observed during scorpion envenomation as they usually target membrane bound ion channels of excitable and non-excitable cells. Several hundred DBPs have been identified and functionally characterized in the past two decades. The NDBPs represent a novel group of molecules that have gained great interest only recently due to their high diversity both in their primary structures and bioactivities. This review provides an overview of scorpion NDBPs focusing on their therapeutic applications, modes of discovery, mechanisms of NDBPs genetic diversity and structural properties. It also provides a simple classification for NDBPs that could be adopted and applied to other NDBPs identified in future studies.

  9. Electrophysiological Characterization of the Antarease Metalloprotease from Tityus serrulatus Venom

    Science.gov (United States)

    Zornetta, Irene; Scorzeto, Michele; Mendes Dos Reis, Pablo Victor; De Lima, Maria E.; Montecucco, Cesare; Megighian, Aram; Rossetto, Ornella

    2017-01-01

    Scorpions are among the oldest venomous living organisms and the family Buthidae is the largest and most medically relevant one. Scorpion venoms include many toxic peptides, but recently, a metalloprotease from Tityus serrulatus called antarease was reported to be capable of cleaving VAMP2, a protein involved in the neuroparalytic syndromes of tetanus and botulism. We have produced antarease and an inactive metalloprotease mutant in a recombinant form and analyzed their enzymatic activity on recombinant VAMP2 in vitro and on mammalian and insect neuromuscular junction. The purified recombinant antarease paralyzed the neuromuscular junctions of mice and of Drosophila melanogaster whilst the mutant was inactive. We were unable to demonstrate any cleavage of VAMP2 under conditions which leads to VAMP proteolysis by botulinum neurotoxin type B. Antarease caused a reduced release probability, mainly due to defects upstream of the synaptic vesicles fusion process. Paired pulse experiments indicate that antarease might proteolytically inactivate a voltage-gated calcium channel. PMID:28264432

  10. Antitumoral Potential of Tunisian Snake Venoms Secreted Phospholipases A2

    Directory of Open Access Journals (Sweden)

    Raoudha Zouari-Kessentini

    2013-01-01

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

  11. Evaluation of the effect of gamma rays on the venom of Vipera lebetina by biochemical study

    Energy Technology Data Exchange (ETDEWEB)

    Bennacef-Heffar, N.; Laraba-Djebari, F. [USTHB Bab Ezzouar, Lab. de Biologie Cellulaire et Moleculaire, Faculte des Sciences Biologiques, Alger (Algeria)]. E-mail: flaraba@ibnsina.ands.dz

    2003-12-01

    Snake bites represent a serious public health problem in many areas of the world. In Algeria, two widespread snakes are Vipera lebetina and Cerastes cerastes. Vipera lebetina venom causes local hemorrhage and necrosis, and it may lead to permanent limb loss. The principal causes of mortality after snakebites are acute renal failure and hemorrhage, which occur not only locally, at the site of the bite, but also systemically, contributing to the cardiovascular shock characteristic of severe envenomation. Gamma radiation has been shown to be effective for attenuating venom toxicity. Vipera lebetina venom was irradiated with two doses of gamma rays (1 and 2 kGy) from a {sup 60}Co source, and the venom's toxic, enzymatic, and structural properties were analyzed. Intraperitoneal injection of the irradiated venoms (100-500 {mu}g/20 g mouse body mass) revealed a significant decrease of the toxicity. Irradiated venoms with 1 and 2 kGy doses were four and nine times less toxic, respectively, than the native venom. A biochemical characterization of in vitro enzymatic activities was performed. Vipera lebetina displayed in vitro caseinolytic, amidolytic, esterasic, coagulant, and phospholipase A{sub 2} activities. Caseinolytic, amidolytic, esterasic, and coagulative activities were reduced for the irradiated venoms; only phospholipase A{sub 2} activity was abolished in the irradiated venom with a dose of 2 kGy. The native and irradiated venoms were separated by gel filtration and electrophoresis. Chromatographic and electrophoretic profiles were drastically changed as compared with the native venom. Vipera lebetina venom detoxified by gamma rays was used for active immunization, and the presence of antibody in the immune sera was detected by ELISA. The immunogenic properties were preserved and the antisera obtained with the irradiated venoms could cross-react. Antisera were able to neutralize the toxic effect of V. lebetina native venom. These results indicate that

  12. Understanding Biological Roles of Venoms Among the Caenophidia: The Importance of Rear-Fanged Snakes.

    Science.gov (United States)

    Mackessy, Stephen P; Saviola, Anthony J

    2016-11-01

    Snake venoms represent an adaptive trophic response to the challenges confronting a limbless predator for overcoming combative prey, and this chemical means of subduing prey shows several dominant phenotypes. Many front-fanged snakes, particularly vipers, feed on various vertebrate and invertebrate prey species, and some of their venom components (e.g., metalloproteinases, cobratoxin) appear to have been selected for "broad-brush" incapacitation of different prey taxa. Using proteomic and genomic techniques, the compositional diversity of front-fanged snakes is becoming well characterized; however, this is not the case for most rear-fanged colubroid snakes. Because these species consume a high diversity of prey, and because venoms are primarily a trophic adaptation, important clues for understanding specific selective pressures favoring venom component composition will be found among rear-fanged snake venoms. Rear-fanged snakes typically (but not always) produce venoms with lower complexity than front-fanged snakes, and there are even fewer dominant (and, arguably, biologically most relevant) venom protein families. We have demonstrated taxon-specific toxic effects, where lizards and birds show high susceptibility while mammals are largely unaffected, for both Old World and New World rear-fanged snakes, strongly indicating a causal link between toxin evolution and prey preference. New data are presented on myotoxin a, showing that the extremely rapid paralysis induced by this rattlesnake toxin is specific for rodents, and that myotoxin a is ineffectual against lizards. Relatively few rear-fanged snake venoms have been characterized, and basic natural history data are largely lacking, but directed sampling of specialized species indicates that novel compounds are likely among these specialists, particularly among those species feeding on invertebrate prey such as scorpions and centipedes. Because many of the more than 2200 species of colubroid snakes are rear

  13. Comparison of venoms from wild and long-term captive Bothrops atrox snakes and characterization of Batroxrhagin, the predominant class PIII metalloproteinase from the venom of this species.

    Science.gov (United States)

    Freitas-de-Sousa, L A; Amazonas, D R; Sousa, L F; Sant'Anna, S S; Nishiyama, M Y; Serrano, S M T; Junqueira-de-Azevedo, I L M; Chalkidis, H M; Moura-da-Silva, A M; Mourão, R H V

    2015-11-01

    Comparisons between venoms from snakes kept under captivity or collected at the natural environment are of fundamental importance in order to obtain effective antivenoms to treat human victims of snakebites. In this study, we compared composition and biological activities of Bothrops atrox venom from snakes collected at Tapajós National Forest (Pará State, Brazil) or maintained for more than 10 years under captivity at Instituto Butantan herpetarium after have been collected mostly at Maranhão State, Brazil. Venoms from captive or wild snakes were similar except for small quantitative differences detected in peaks correspondent to phospholipases A2 (PLA2), snake venom metalloproteinases (SVMP) class PI and serine proteinases (SVSP), which did not correlate with fibrinolytic and coagulant activities (induced by PI-SVMPs and SVSPs). In both pools, the major toxic component corresponded to PIII-SVMPs, which were isolated and characterized. The characterization by mass spectrometry of both samples identified peptides that matched with a single PIII-SVMP cDNA characterized by transcriptomics, named Batroxrhagin. Sequence alignments show a strong similarity between Batroxrhagin and Jararhagin (96%). Batroxrhagin samples isolated from venoms of wild or captive snakes were not pro-coagulant, but inhibited collagen-induced platelet-aggregation, and induced hemorrhage and fibrin lysis with similar doses. Results suggest that in spite of environmental differences, venom variability was detected only among the less abundant components. In opposition, the most abundant toxin, which is a PIII-SVMP related to the key effects of the venom, is structurally conserved in the venoms. This observation is relevant for explaining the efficacy of antivenoms produced with venoms from captive snakes in human accidents inflicted at distinct natural environments.

  14. Inhibitory and enzyme-kinetic investigation of chelerythrine and lupeol isolated from Zanthoxylum rhoifolium against krait snake venom acetylcholinesterase

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Mustaq, E-mail: mushtaq213@yahoo.com [University of Science and Technology, Bannu, (Pakistan). Department of Biotechnology; Weber, Andrea D.; Zanon, Graciane; Tavares, Luciana de C.; Ilha, Vinicius; Dalcol, Ionara I.; Morel, Ademir F., E-mail: ademirfariasm@gmail.com [Universidade Federal de Santa Maria, RS (Brazil). Dept. de Quimica

    2014-01-15

    The in vitro activity of chelerythrine and lupeol, two metabolites isolated from Zanthoxylum rhoifolium were studied against the venom of the snake Bungarus sindanus (Elapidae). The venom, which is highly toxic to humans, consists mainly by the enzyme acetylcholinesterase (AChE). Both compounds showed activity against the venom, and the alkaloid chelerythrine presented higher activity than did triterpene lupeol. (author)

  15. Elucidation of the molecular envenomation strategy of the cone snail Conus geographus through transcriptome sequencing of its venom duct

    Directory of Open Access Journals (Sweden)

    Hu Hao

    2012-06-01

    Full Text Available Abstract Background The fish-hunting cone snail, Conus geographus, is the deadliest snail on earth. In the absence of medical intervention, 70% of human stinging cases are fatal. Although, its venom is known to consist of a cocktail of small peptides targeting different ion-channels and receptors, the bulk of its venom constituents, their sites of manufacture, relative abundances and how they function collectively in envenomation has remained unknown. Results We have used transcriptome sequencing to systematically elucidate the contents the C. geographus venom duct, dividing it into four segments in order to investigate each segment’s mRNA contents. Three different types of calcium channel (each targeted by unrelated, entirely distinct venom peptides and at least two different nicotinic receptors appear to be targeted by the venom. Moreover, the most highly expressed venom component is not paralytic, but causes sensory disorientation and is expressed in a different segment of the venom duct from venoms believed to cause sensory disruption. We have also identified several new toxins of interest for pharmaceutical and neuroscience research. Conclusions Conus geographus is believed to prey on fish hiding in reef crevices at night. Our data suggest that disorientation of prey is central to its envenomation strategy. Furthermore, venom expression profiles also suggest a sophisticated layering of venom-expression patterns within the venom duct, with disorientating and paralytic venoms expressed in different regions. Thus, our transcriptome analysis provides a new physiological framework for understanding the molecular envenomation strategy of this deadly snail.

  16. PHARMACOLOGICAL EFFECTS OF SNAKE VENOM L- AMINO ACID OXIDASES

    OpenAIRE

    Joseph Baby; Rajan Sheeja S; M.V Jeevitha; S.U Ajisha

    2011-01-01

    L-Amino acid oxidases are flavoenzymes which catalyze the stereospecific oxidative deamination of an L-amino acid substrate to a corresponding a-ketoacid with hydrogen peroxide and ammonia production. These enzymes, which are widely distributed in many different organisms, exhibit a marked affinity for hydrophobic amino acids, including phenylalanine, tryptophan, tyrosine, and leucine. Snake venom LAAO induces platelet aggregation and cytotoxicity in various cancer cell lines. The enzyme has ...

  17. Neuromuscular Activity of Micrurus laticollaris (Squamata: Elapidae Venom in Vitro

    Directory of Open Access Journals (Sweden)

    Alejandro Carbajal-Saucedo

    2014-01-01

    Full Text Available In this work, we have examined the neuromuscular activity of Micrurus laticollaris (Mexican coral snake venom (MLV in vertebrate isolated nerve-muscle preparations. In chick biventer cervicis preparations, the MLV induced an irreversible concentration- and time-dependent (1–30 µg/mL neuromuscular blockade, with 50% blockade occurring between 8 and 30 min. Muscle contractures evoked by exogenous acetylcholine were completely abolished by MLV, whereas those of KCl were also significantly altered (86% ± 11%, 53% ± 11%, 89% ± 5% and 89% ± 7% for one, three, 10 and 30 µg of venom/mL, respectively; n = 4; p < 0.05. In mouse phrenic nerve-diaphragm preparations, MLV (1–10 µg/mL promoted a slight increase in the amplitude of twitch-tension (3 µg/mL, followed by neuromuscular blockade (n = 4; the highest concentration caused complete inhibition of the twitches (time for 50% blockade = 26 ± 3 min, without exhibiting a previous neuromuscular facilitation. The venom (3 µg/mL induced a biphasic modulation in the frequency of miniature end-plate potentials (MEPPs/min, causing a significant increase after 15 min, followed by a decrease after 60 min (from 17 ± 1.4 (basal to 28 ± 2.5 (t15 and 12 ± 2 (t60. The membrane resting potential of mouse diaphragm preparations pre-exposed or not to d-tubocurarine (5 µg/mL was also significantly less negative with MLV (10 µg/mL. Together, these results indicate that M. laticollaris venom induces neuromuscular blockade by a combination of pre- and post-synaptic activities.

  18. Scorpion venoms: taking the sting out of lung disease.

    OpenAIRE

    1996-01-01

    Scorpion venoms contain specific toxins which block large conductance calcium-activated potassium (BKCa) channels. Use of these toxins has shown that a significant proportion of the action of bronchodilators such as beta-agonists, theophylline, and nitric oxide occurs as a result of the opening of BKCa channels. Similarly, these toxins have shown that inhibitors of airway neurotransmission also operate via BKCa channels. Drugs that open BKCa channels may be alternative bronchodilators (possib...

  19. Radioprotection: mechanism and radioprotective agents including honeybee venom

    Energy Technology Data Exchange (ETDEWEB)

    Varanda, E.A.; Tavares, D.C. [UNESP, Araraquara, SP (Brazil). Escola de Ciencias Farmaceuticas. Dept. de Ciencias Biologicas

    1998-07-01

    Since 1949, a great deal of research has been carried on the radioprotective action of chemical substances. These substances have shown to reduce mortality when administered to animals prior to exposure to a lethal dose of radiation. This fact is of considerable importance since it permits reduction of radiation-induced damage and provides prophylactic treatment for the damaging effects produced by radiotherapy. The following radioprotection mechanisms were proposed: free radical scavenger, repair by hydrogen donation to target molecules formation of mixed disulfides, delay of cellular division and induction of hypoxia in the tissues. Radioprotective agents have been divided into four major groups: the thiol compounds, other sulfur compounds, pharmacological agents (anesthetic drugs, analgesics, tranquilizers, etc.) and other radioprotective agents (WR-1065, WR-2721, vitamins C and E, glutathione, etc.). Several studies revealed the radioprotective action of Apis mellifera honeybee venom as well as that of its components mellitin and histamine. Radioprotective activity of bee venom involves mainly the stimulation of the hematopoietic system. In addition, release of histamine and reduction in oxygen tension also contribute to the radioprotective action of bee venom. (author)

  20. Australian venomous jellyfish, envenomation syndromes, toxins and therapy.

    Science.gov (United States)

    Tibballs, James

    2006-12-01

    The seas and oceans around Australia harbour numerous venomous jellyfish. Chironex fleckeri, the box jellyfish, is the most lethal causing rapid cardiorespiratory depression and although its venom has been characterised, its toxins remain to be identified. A moderately effective antivenom exists which is also partially effective against another chirodropid, Chiropsalmus sp. Numerous carybdeids, some unidentified, cause less severe illness, including Carybdea rastoni whose toxins CrTX-A and CrTX-B are large proteins. Carukia barnesi, another small carybdeid is one cause of the 'Irukandji' syndrome which includes delayed pain from severe muscle cramping, vomiting, anxiety, restlessness, sweating and prostration, and occasionally severe hypertension and acute cardiac failure. The syndrome is in part caused by release of catecholamines but the cause of heart failure is undefined. The venom contains a sodium channel modulator. Two species of Physalia are present and although one is potentially lethal, has not caused death in Australian waters. Other significant genera of jellyfish include Tamoya, Pelagia, Cyanea, Aurelia and Chyrosaora.

  1. Scorpions from Mexico: From Species Diversity to Venom Complexity.

    Science.gov (United States)

    Santibáñez-López, Carlos E; Francke, Oscar F; Ureta, Carolina; Possani, Lourival D

    2015-12-24

    Scorpions are among the oldest terrestrial arthropods, which are distributed worldwide, except for Antarctica and some Pacific islands. Scorpion envenomation represents a public health problem in several parts of the world. Mexico harbors the highest diversity of scorpions in the world, including some of the world's medically important scorpion species. The systematics and diversity of Mexican scorpion fauna has not been revised in the past decade; and due to recent and exhaustive collection efforts as part of different ongoing major revisionary systematic projects, our understanding of this diversity has changed compared with previous assessments. Given the presence of several medically important scorpion species, the study of their venom in the country is also important. In the present contribution, the diversity of scorpion species in Mexico is revised and updated based on several new systematic contributions; 281 different species are recorded. Commentaries on recent venomic, ecological and behavioral studies of Mexican scorpions are also provided. A list containing the most important peptides identified from 16 different species is included. A graphical representation of the different types of components found in these venoms is also revised. A map with hotspots showing the current knowledge on scorpion distribution and areas explored in Mexico is also provided.

  2. Importance of basophil activation testing in insect venom allergy

    Directory of Open Access Journals (Sweden)

    Kosnik Mitja

    2009-12-01

    Full Text Available Abstract Background Venom immunotherapy (VIT is the only effective treatment for prevention of serious allergic reactions to bee and wasp stings in sensitized individuals. However, there are still many questions and controversies regarding immunotherapy, like selection of the appropriate allergen, safety and long term efficacy. Methods Literature review was performed to address the role of basophil activation test (BAT in diagnosis of venom allergy. Results In patients with positive skin tests or specific IgE to both honeybee and wasp venom, IgE inhibition test can identify sensitizing allergen only in around 15% and basophil activation test increases the identification rate to around one third of double positive patients. BAT is also diagnostic in majority of patients with systemic reactions after insect stings and no detectable IgE. High basophil sensitivity to allergen is associated with a risk of side effects during VIT. Persistence of high basophil sensitivity also predicts a treatment failure of VIT. Conclusion BAT is a useful tool for better selection of allergen for immunotherapy, for identification of patients prone to side effects and patients who might be treatment failures. However, long term studies are needed to evaluate the accuracy of the test.

  3. Snake venom metalloproteinases and disintegrins: interactions with cells

    Directory of Open Access Journals (Sweden)

    Kamiguti A.S.

    1998-01-01

    Full Text Available Metalloproteinases and disintegrins are important components of most viperid and crotalid venoms. Large metalloproteinases referred to as MDC enzymes are composed of an N-terminal Metalloproteinase domain, a Disintegrin-like domain and a Cys-rich C-terminus. In contrast, disintegrins are small non-enzymatic RGD-containing cysteine-rich polypeptides. However, the disintegrin region of MDC enzymes bears a high degree of structural homology to that of the disintegrins, although it lacks the RGD motif. Despite these differences, both components share the property of being able to recognize integrin cell surface receptors and thereby to inhibit integrin-dependent cell reactions. Recently, several membrane-bound MDC enzymes, closely related to soluble venom MDC enzymes, have been described in mammalian cells. This group of membrane-anchored mammalian enzymes is also called the ADAM family of proteins due to the structure revealing A Disintegrin And Metalloproteinase domains. ADAMs are involved in the shedding of molecules from the cell surface, a property which is also shared by some venom MDC enzymes.

  4. RENO, NV, JANUARY 15, 2004: FACTORS IMPLICATED IN AMPHIBIAN POPULATION DECLINES IN THE UNITED STATES

    Science.gov (United States)

    Factors known or suspected to be adversely affecting native amphibian populations in the US were identified using information from 267 species accounts written in a standardized format by multiple authors in the forthcoming book, 'Status and Conservation of U.S. Amphibians'. Spec...

  5. Ultraviolet radiation and Vitamin D3 in amphibian health, behaviour, diet and conservation.

    Science.gov (United States)

    Antwis, R E; Browne, R K

    2009-10-01

    Amphibians are currently suffering a period of mass extinction with approximately 20% of species under severe threat and more than 120 species already extinct. In light of this crisis there is an urgency to establish viable ex situ populations and also find the causes of in situ declines. The role of ultraviolet radiation and Vitamin D(3) in amphibian health directly influences both ex situ and in situ populations. Vitamin D(3) can be photosynthesised endogenously via UV-B radiation (UV-B), or acquired through the diet, and then metabolised to calcitriol the biologically active hormonal form. Although, there is a lack of literature concerning Vitamin D(3) requirements and calcitriol synthesis in amphibians, amphibians are likely to have similar Vitamin D(3) requirements and metabolic processes as other vertebrates due to the phylogenetically conservative nature of calcitriol biosynthesis. Deficiencies in calcitriol in amphibians result in nutritional metabolic bone disease (NMBD) and could compromise reproduction and immunity. However, excess biologically active UV radiation has also proven detrimental across all three amphibian life stages and therefore could impact both in situ and ex situ populations. Here we review the role and necessity of UV-B and calcitriol in amphibians and the potential for negative impacts due to excessive exposure to UV radiation. We also identify priorities for research that could provide critical information for maintaining healthy in ex situ and in situ populations of amphibians.

  6. Amphibian and reptile records from around the Betsiboka Delta area in North-Western Madagascar

    NARCIS (Netherlands)

    Rakotoarison, Andolalao; Erens, Jesse; Ratsoavina, Fanomezana M.; Vences, Miguel

    2015-01-01

    This study summarises amphibian and reptile records from ad hoc surveys in a series of localities in the North-West of Madagascar, largely centred on the delta of the Betsiboka River. Eleven amphibian and approximately 32 reptile species were found, with taxonomic uncertainties remaining for some

  7. What's Slithering around on Your School Grounds? Transforming Student Awareness of Reptile & Amphibian Diversity

    Science.gov (United States)

    Tomasek, Terry M.; Matthews, Catherine E.; Hall, Jeff

    2005-01-01

    The protocols used in a research project on amphibian and reptile diversity at Cool Springs Environmental Education Center near New Bern, North Carolina is described. An increasing or stable number of amphibians and reptiles would indicate that the forest has a balance of invertebrates, leaf litter, moisture, pH, debris, burrows and habitat…

  8. Phase-II conjugation ability for PAH metabolism in amphibians: characteristics and inter-species differences.

    Science.gov (United States)

    Ueda, Haruki; Ikenaka, Yoshinori; Nakayama, Shouta M M; Tanaka-Ueno, Tomoko; Ishizuka, Mayumi

    2011-10-01

    The present study examines amphibian metabolic activity - particularly conjugation - by analysis of pyrene (a four ring, polycyclic aromatic hydrocarbon) metabolites using high-performance liquid chromatography (HPLC) with fluorescence detector (FD), a mass spectrometry detector (MS) system and kinetic analysis of conjugation enzymes. Six amphibian species were exposed to pyrene (dissolved in water): African claw frog (Xenopus laevis); Tago's brown frog (Rana tagoi); Montane brown frog (Rana ornativentris); Wrinkled frog (Rana rugosa); Japanese newt (Cynops pyrrhogaster); and Clouded salamander (Hynobius nebulosus); plus one fish species, medaka (Oryzias latipes); and a fresh water snail (Clithon retropictus), and the resultant metabolites were collected. Identification of pyrene metabolites by HPLC and ion-trap MS system indicated that medaka mainly excreted pyrene-1-glucuronide (PYOG), while pyrene-1-sulfate (PYOS) was the main metabolite in all amphibian species. Pyrene metabolites in amphibians were different from those in invertebrate fresh water snails. Inter-species differences were also observed in pyrene metabolism among amphibians. Metabolite analysis showed that frogs relied more strongly on sulfate conjugation than did Japanese newts and clouded salamanders. Furthermore, urodelan amphibians, newts and salamanders, excreted glucose conjugates of pyrene that were not detected in the anuran amphibians. Kinetic analysis of conjugation by hepatic microsomes and cytosols indicated that differences in excreted metabolites reflected differences in enzymatic activities. Furthermore, pyrenediol (PYDOH) glucoside sulfate was detected in the Japanese newt sample. This novel metabolite has not been reported previously to this report, in which we have identified unique characteristics of amphibians in phase II pyrene metabolism.

  9. Batrachochytrium dendrobatidis prevalence and haplotypes in domestic and imported pet amphibians in Japan.

    Science.gov (United States)

    Tamukai, Kenichi; Une, Yumi; Tominaga, Atsushi; Suzuki, Kazutaka; Goka, Koichi

    2014-05-13

    The international trade in amphibians is believed to have increased the spread of Batrachochytrium dendrobatidis (Bd), the fungal pathogen responsible for chytridiomycosis, which has caused a rapid decline in amphibian populations worldwide. We surveyed amphibians imported into Japan and those held in captivity for a long period or bred in Japan to clarify the Bd infection status. Samples were taken from 820 individuals of 109 amphibian species between 2008 and 2011 and were analyzed by a nested-PCR assay. Bd prevalence in imported amphibians was 10.3% (58/561), while it was 6.9% (18/259) in those in private collections and commercially bred amphibians in Japan. We identified the genotypes of this fungus using partial DNA sequences of the internal transcribed spacer (ITS) region. Sequencing of PCR products of all 76 Bd-positive samples revealed 11 haplotypes of the Bd ITS region. Haplotype A (DNA Data Bank of Japan accession number AB435211) was found in 90% (52/58) of imported amphibians. The results show that Bd is currently entering Japan via the international trade in exotic amphibians as pets, suggesting that the trade has indeed played a major role in the spread of Bd.

  10. 14 CFR 29.519 - Hull type rotorcraft: Water-based and amphibian.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hull type rotorcraft: Water-based and amphibian. 29.519 Section 29.519 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... § 29.519 Hull type rotorcraft: Water-based and amphibian. (a) General. For hull type rotorcraft,...

  11. Mitigating amphibian chytridiomycosis with bioaugmentation: characteristics of effective probiotics and strategies for their selection and use.

    Science.gov (United States)

    Bletz, Molly C; Loudon, Andrew H; Becker, Matthew H; Bell, Sara C; Woodhams, Douglas C; Minbiole, Kevin P C; Harris, Reid N

    2013-06-01

    Probiotic therapy through bioaugmentation is a feasible disease mitigation strategy based on growing evidence that microbes contribute to host defences of plants and animals. Amphibians are currently threatened by the rapid global spread of the pathogen, Batrachochytrium dendrobatidis (Bd), which causes the disease chytridiomycosis. Bioaugmentation of locally occurring protective bacteria on amphibians has mitigated this disease effectively in laboratory trials and one recent field trial. Areas still naïve to Bd provide an opportunity for conservationists to proactively implement probiotic strategies to prevent further amphibian declines. In areas where Bd is endemic, bioaugmentation can facilitate repatriation of susceptible amphibians currently maintained in assurance colonies. Here, we synthesise the current research in amphibian microbial ecology and bioaugmentation to identify characteristics of effective probiotics in relation to their interactions with Bd, their host, other resident microbes and the environment. To target at-risk species and amphibian communities, we develop sampling strategies and filtering protocols that result in probiotics that inhibit Bd under ecologically relevant conditions and persist on susceptible amphibians. This filtering tool can be used proactively to guide amphibian disease mitigation and can be extended to other taxa threatened by emerging infectious diseases.

  12. A meta-analysis of the effects of pesticides and fertilizers on survival and growth of amphibians.

    Science.gov (United States)

    Baker, Nick J; Bancroft, Betsy A; Garcia, Tiffany S

    2013-04-01

    The input of agrochemicals has contributed to alteration of community composition in managed and associated natural systems, including amphibian biodiversity. Pesticides and fertilizers negatively affect many amphibian species and can cause mortality and sublethal effects, such as reduced growth and increased susceptibility to disease. However, the effect of pesticides and fertilizers varies among amphibian species. We used meta-analytic techniques to quantify the lethal and sublethal effects of pesticides and fertilizers on amphibians in an effort to review the published work to date and produce generalized conclusions. We found that pesticides and fertilizers had a negative effect on survival of -0.9027 and growth of -0.0737 across all reported amphibian species. We also observed differences between chemical classes in their impact on amphibians: inorganic fertilizers, organophosphates, chloropyridinyl, phosphonoglycines, carbamates, and triazines negatively affected amphibian survival, while organophosphates and phosphonoglycines negatively affected amphibian growth. Our results suggest that pesticides and fertilizers are an important stressor for amphibians in agriculturally dominated systems. Furthermore, certain chemical classes are more likely to harm amphibians. Best management practices in agroecosystems should incorporate amphibian species-specific response to agrochemicals as well as life stage dependent susceptibility to best conserve amphibian biodiversity in these landscapes.

  13. [Isolation and partial structural characteristics of major toxic components of Latrodectus pallidus venom].

    Science.gov (United States)

    Charakha, A R; Shevchenko, L V; Molodkin, A K; Pluzhnikov, K A; Volkova, T M; Grishin, E V

    1997-03-01

    Toxic components of the Latrodectus pallidus spider venom were isolated and characterized. The venom was shown to contain a toxin specific for mammals and at least one insectospecific toxin. Partial amino acid sequences of both toxins were determined, and their high structural homology with previously studied alpha-latrotoxin and alpha-latroinsectotoxin from L. mactans tredecimguttatus was found.

  14. Maturity-related changes in venom toxicity of the freshwater stingray Potamotrygon leopoldi.

    Science.gov (United States)

    Kirchhoff, Kim N; Klingelhöfer, Ines; Dahse, Hans-Martin; Morlock, Gertrud; Wilke, Thomas

    2014-12-15

    Aquatic venomous animals such as stingrays represent a largely untapped source for venom-based drug development. However, the major challenge for a potential drug development pipeline is the high inter- and intraspecific variability in toxicity and venom composition. As of today, little is known about maturity-driven changes in these traits in stingrays. The present study investigates the differences in toxicity and venom composition in different maturity stages of the freshwater stingray Potamotrygon leopoldi. This species can be found in the Xingú River basin (Brazil), where it mainly feeds on invertebrates, while being predated by other stingrays or large catfishes. P. leopoldi, as commonly known for stingrays, can cause severe injuries with the venomous dentine spine located at its tails. The toxicity of tissue extracts of juvenile and mature specimens was recorded on a myoblast cell culture bioassay. Venom composition and bioactivity of compounds were analyzed with planar chromatography linked to an Aliivibrio fischeri bioassay. Results revealed a decrease in venom toxicity during maturation, but no changes in venom composition. These findings may indicate that toxicity in mature specimens becomes evolutionary less important, probably due to a decrease in predation pressure.

  15. Characterization of inflammatory response induced by Potamotrygon motoro stingray venom in mice.

    Science.gov (United States)

    Kimura, Louise F; Prezotto-Neto, José P; Antoniazzi, Marta M; Jared, Simone Gs; Santoro, Marcelo L; Barbaro, Katia C

    2014-05-01

    Freshwater stingray accidents cause intense pain followed by edema, erythema, and necrosis formation. Treatment for stingray envenomation is based on administration of analgesic, antipyretic, and anti-inflammatory drugs. This report evaluated the local inflammatory reaction-including edema formation, leukocyte recruitment, release of inflammatory mediators, and histopathological changes-after the intraplantar injection of Potamotrygon motoro stingray venom in mice. Edema was observed as soon as 15 min after venom injection, peaking at 30 min, and lasted up to 48 h. In addition, P. motoro venom increased neutrophil counts in the site of injection, at all time periods and venom doses analyzed. Increased eosinophil and lymphocyte counts were detected mainly at 24 h. Moreover, monocytes/macrophages were observed in large amounts at 24 and 48 h. Microscopically, the venom induced leukocyte migration to the injured tissue, edema, mast cell degranulation, angiogenesis, and epidermal damage. Inflammatory mediator release (IL-6, MCP-1 and KC) was detected as soon as 1 h after venom injection, and it increased significantly at 4 h. At 24 h, the venom induced only the production of MCP-1. These results show that this stingray venom evokes a complex inflammatory reaction, with rapid and persistent edema formation, leukocyte recruitment, and release of cytokines and chemokines.

  16. In Vitro Toxic Effects of Puff Adder (Bitis arietans Venom, and Their Neutralization by Antivenom

    Directory of Open Access Journals (Sweden)

    Steven Fernandez

    2014-05-01

    Full Text Available This study investigated the in vitro toxic effects of Bitis arietans venom and the ability of antivenom produced by the South African Institute of Medical Research (SAIMR to neutralize these effects. The venom (50 µg/mL reduced nerve-mediated twitches of the chick biventer muscle to 19% ± 2% of initial magnitude (n = 4 within 2 h. This inhibitory effect of the venom was significantly attenuated by prior incubation of tissues with SAIMR antivenom (0.864 µg/µL; 67% ± 4%; P < 0.05; n = 3–5, unpaired t-test. Addition of antivenom at t50 failed to prevent further inhibition or reverse the inhibition of twitches and responses to agonists. The myotoxic action of the venom (50 µg/mL was evidenced by a decrease in direct twitches (30% ± 6% of the initial twitch magnitude and increase in baseline tension (by 0.7 ± 0.3 g within 3 h of the chick biventer. Antivenom failed to block these effects. Antivenom however prevented the venom induced cytotoxic effects on L6 skeletal muscle cells. Venom induced a marginal but significant reduction in plasma clotting times at concentrations above 7.8 µg/100 µL of plasma, indicating poor procoagulant effects. In addition, the results of western immunoblotting indicate strong immunoreactivity with venom proteins, thus warranting further detailed studies on the neutralization of the effects of individual venom toxins by antivenom.

  17. Evolution of separate predation- and defence-evoked venoms in carnivorous cone snails.

    Science.gov (United States)

    Dutertre, Sébastien; Jin, Ai-Hua; Vetter, Irina; Hamilton, Brett; Sunagar, Kartik; Lavergne, Vincent; Dutertre, Valentin; Fry, Bryan G; Antunes, Agostinho; Venter, Deon J; Alewood, Paul F; Lewis, Richard J

    2014-03-24

    Venomous animals are thought to inject the same combination of toxins for both predation and defence, presumably exploiting conserved target pharmacology across prey and predators. Remarkably, cone snails can rapidly switch between distinct venoms in response to predatory or defensive stimuli. Here, we show that the defence-evoked venom of Conus geographus contains high levels of paralytic toxins that potently block neuromuscular receptors, consistent with its lethal effects on humans. In contrast, C. geographus predation-evoked venom contains prey-specific toxins mostly inactive at human targets. Predation- and defence-evoked venoms originate from the distal and proximal regions of the venom duct, respectively, explaining how different stimuli can generate two distinct venoms. A specialized defensive envenomation strategy is widely evolved across worm, mollusk and fish-hunting cone snails. We propose that defensive toxins, originally evolved in ancestral worm-hunting cone snails to protect against cephalopod and fish predation, have been repurposed in predatory venoms to facilitate diversification to fish and mollusk diets.

  18. Determination of the Median Lethal Dose and Electrophoretic Pattern of Hottentotta saulcyi (Scorpiones, Buthidae Scorpion Venom

    Directory of Open Access Journals (Sweden)

    ErsenAydın Yağmur

    2015-10-01

    Full Text Available Background: In this study, we investigated the lethal potency, electrophoretic protein pattern and in vivo effects of Hottentotta saulcyi scorpion venom in mice.Methods: Scorpions were collected at night, by using a UV lamp from Mardin Province, Turkey. Venom was obtained from mature H. saulcyi scorpions by electrical stimulation of the telson. The lethality of the venom was determined by i.v. injections using Swiss mice. In vivo effects of the venom were assessed by using the intraperitoneal route (ip injections into mice (20±1g and monitored for 24 h. The protein profiles of the scorpion venom were analyzed by NuPAGE® Novex® 4–12 % gradient Bis-Tris gel followed by Coomassie blue staining.Results: The lethal assay of the venom was 0.73 mg/kg in mice. We determined the electrophoretic protein pattern of this scorpion venom to be 4, 6, 9, 31, 35, 40, 46 and 69 kDa by SDS-PAGE. Analysis of electrophoresis indicated that H. saulcyi scorpion intoxicated mice exhibited autonomic nervous system symptoms (tachypnea, restlessness, hyperexcitability, convulsions, salivation, lacrimation, weakness.Conclusions: Hottentotta saulcyi scorpion venom includes short-chain neurotoxins and long-chain neurotoxins according to the electrophoretic protein patterns. The stings of H. saulcyi scorpion must be considered of risk for humans in the southeastern region, Turkey.

  19. Peptidomics combined with cDNA library unravel the diversity of centipede venom

    DEFF Research Database (Denmark)

    Rong, Mingqiang; Yang, Shilong; Wen, Bo

    2015-01-01

    showed a larger different to known peptide toxins such spider or scorpion toxins. Moreover, only 29 peptides from this centipede venom were identified with known function. It suggested that our work not only important to understand the composition of centipede venom, but also provide many valuable...

  20. Tentacle Transcriptome and Venom Proteome of the Pacific Sea Nettle, Chrysaora fuscescens (Cnidaria: Scyphozoa

    Directory of Open Access Journals (Sweden)

    Dalia Ponce

    2016-04-01

    Full Text Available Jellyfish venoms are rich sources of toxins designed to capture prey or deter predators, but they can also elicit harmful effects in humans. In this study, an integrated transcriptomic and proteomic approach was used to identify putative toxins and their potential role in the venom of the scyphozoan jellyfish Chrysaora fuscescens. A de novo tentacle transcriptome, containing more than 23,000 contigs, was constructed and used in proteomic analysis of C. fuscescens venom to identify potential toxins. From a total of 163 proteins identified in the venom proteome, 27 were classified as putative toxins and grouped into six protein families: proteinases, venom allergens, C-type lectins, pore-forming toxins, glycoside hydrolases and enzyme inhibitors. Other putative toxins identified in the transcriptome, but not the proteome, included additional proteinases as well as lipases and deoxyribonucleases. Sequence analysis also revealed the presence of ShKT domains in two putative venom proteins from the proteome and an additional 15 from the transcriptome, suggesting potential ion channel blockade or modulatory activities. Comparison of these potential toxins to those from other cnidarians provided insight into their possible roles in C. fuscescens venom and an overview of the diversity of potential toxin families in cnidarian venoms.

  1. Intersexual variations in the pharmacological properties of Coremiocnemis tropix (Araneae, Theraphosidae) spider venom.

    Science.gov (United States)

    Herzig, Volker; Hodgson, Wayne C

    2009-02-01

    This study aimed to determine the biochemical, insecticidal and neurotoxic properties of venom from both sexes of the Australian spider Coremiocnemis tropix (Araneae, Theraphosidae). Insecticidal properties were tested in crickets, while in vitro neurotoxicity was determined in an avian skeletal muscle preparation. Some intersexual differences in venom composition were identified by rp-HPLC and by LC-MS, but the majority of components were found in venoms of both sexes. Injecting the venom into crickets revealed that venom from male specimens was slightly more potent, while female venom induced more prominent effects in the chick biventer cervicis nerve-muscle preparation. The results from the chick assay suggest the presence of at least two vertebrate-active neurotoxins. A pre-synaptic neurotoxin may explain the reversible inhibition of muscle twitches and the unaffected response to nicotinic agonists at medium concentrations of female and medium to high concentrations of male venom. In addition, the presence of a neurotoxin that blocks post-synaptic nicotinic receptors might explain the irreversible inhibition of muscle twitches and the reduced response to nicotinic agonists at high concentrations (5-10 microg/ml) of venom from female specimens only.

  2. Comparative analyses of venoms from American and African Sicarius spiders that differ in sphingomyelinase D activity.

    Science.gov (United States)

    Zobel-Thropp, Pamela A; Bodner, Melissa R; Binford, Greta J

    2010-06-15

    Spider venoms are cocktails of toxic proteins and peptides, whose composition varies at many levels. Understanding patterns of variation in chemistry and bioactivity is fundamental for understanding factors influencing variation. The venom toxin sphingomyelinase D (SMase D) in sicariid spider venom (Loxosceles and Sicarius) causes dermonecrotic lesions in mammals. Multiple forms of venom-expressed genes with homology to SMase D are expressed in venoms of both genera. SMase D activity levels differ among major clades with American Sicarius vastly reduced relative to all Loxosceles and African Sicarius despite expression of SMase D homologs in venoms of American Sicarius. Here we report comparative analyses of protein composition and insecticidal activity of crude venoms from three Sicarius species, two from South Africa and one from Central America. Comparative 2-dimensional electrophoresis shows dense regions of proteins in the size range of SMase D in all three species, but there are differences in sizes and isoelectric points (pIs). Few proteins strictly co-migrate and there are clusters of proteins with similar pIs and molecular weights whose patterns of similarity do not necessarily reflect phylogenetic relatedness. In addition, PD(50) estimates on crickets indicate a small though significant decrease in potency of South American Sicarius venoms relative to African species.

  3. Proteomic Characterization and Comparison of Malaysian Tropidolaemus wagleri and Cryptelytrops purpureomaculatus Venom Using Shotgun-Proteomics

    Directory of Open Access Journals (Sweden)

    Syafiq Asnawi Zainal Abidin

    2016-10-01

    Full Text Available Tropidolaemus wagleri and Cryptelytrops purpureomaculatus are venomous pit viper species commonly found in Malaysia. Tandem mass spectrometry analysis of the crude venoms has detected different proteins in T. wagleri and C. purpureomaculatus. They were classified into 13 venom protein families consisting of enzymatic and nonenzymatic proteins. Enzymatic families detected in T. wagleri and C. purpureomaculatus venom were snake venom metalloproteinase, phospholipase A2, ʟ-amino acid oxidase, serine proteases, 5′-nucleotidase, phosphodiesterase, and phospholipase B. In addition, glutaminyl cyclotransferase was detected in C. purpureomaculatus. C-type lectin-like proteins were common nonenzymatic components in both species. Waglerin was present and unique to T. wagleri—it was not in C. purpureomaculatus venom. In contrast, cysteine-rich secretory protein, bradykinin-potentiating peptide, and C-type natriuretic peptide were present in C. purpureomaculatus venom. Composition of the venom proteome of T. wagleri and C. purpureomaculatus provides useful information to guide production of effective antivenom and identification of proteins with potential therapeutic applications.

  4. New analysis of the toxic compounds from the Androctonus mauretanicus mauretanicus scorpion venom.

    Science.gov (United States)

    Oukkache, Naoual; Rosso, Jean-Pierre; Alami, Meriem; Ghalim, Norredine; Saïle, Rachid; Hassar, Mohammed; Bougis, Pierre E; Martin-Eauclaire, Marie-France

    2008-04-01

    Scorpion venoms are very complex mixtures of molecules, most of which are peptides displaying different kinds of biological activity. Indeed, these peptides specifically bind to a variety of pharmacological targets, in particular ionic channels located in prey tissues, resulting in neurotoxic effects. Toxins modulating Na+, K+, Ca2+ and Cl(-) currents have been described in scorpion venoms. In this work, we have used several specific antibodies raised against the most lethal scorpion toxins already described to screen the Moroccan scorpion Androctonus mauretanicus mauretanicus venom in order to characterize new compounds. This immunological screening was also implemented by toxicity tests in mice and with mass spectrometry study, providing new informations on the molecular composition of this venom. In fine, we were able to determine the molecular masses of 70-80 different compounds. According to the immunological data obtained, many toxins cross-react with three sera raised against the most lethal alpha-toxins found in North African scorpion venoms, but not at all with those raised against the main beta-toxins from South and North American venoms. Some of the previously described toxins from Androctonus mauretanicus mauretanicus venom could thus be detected by combining immunological tests, toxicity in mice and molecular masses. Among these toxins, one of them, which showed a mild cross-reaction with the serum raised against AaH I (a highly potent toxin from the venom of Androctonus australis), was identified as Amm III and fully sequenced.

  5. Environmental refuge from disease-driven amphibian extinction.

    Science.gov (United States)

    Puschendorf, Robert; Hoskin, Conrad J; Cashins, Scott D; McDonald, Keith; Skerratt, Lee F; Vanderwal, Jeremy; Alford, Ross A

    2011-10-01

    Species that are tolerant of broad environmental gradients may be less vulnerable to epizootic outbreaks of disease. Chytridriomycosis, caused by the fungus Batrachochytrium dendrobatidis, has been linked to extirpations and extinctions of amphibian species in many regions. The pathogen thrives in cool, moist environments, and high amphibian mortality rates have commonly occurred during chytridiomycosis outbreaks in amphibian populations in high-elevation tropical rainforests. In Australia several high-elevation species, including the armored mist frog (Litoria lorica), which is designated as critically endangered by the International Union for the Conservation of Nature (IUCN), were believed to have gone extinct during chytridiomycosis outbreaks in the 1980s and early 1990s. Species with greater elevational ranges disappeared from higher elevations, but remained common in the lowlands. In June 2008, we surveyed a stream in a high-elevation dry sclerophyll forest and discovered a previously unknown population of L. lorica and a population of the waterfall frog (Litoria nannotis). We conducted 6 additional surveys in June 2008, September 2008, March 2009, and August 2009. Prevalences of B. dendrobatidis infection (number infected per total sampled) were consistently high in frogs (mean 82.5%, minimum 69%) of both species and in tadpoles (100%) during both winter (starting July) and summer (starting February). However, no individuals of either species showed clinical signs of disease, and they remained abundant (3.25 - 8.75 individuals of L. lorica and 6.5-12.5 individuals of L. nannotis found/person/100 m over 13 months). The high-elevation dry sclerophyll site had little canopy cover, low annual precipitation, and a more defined dry season than a nearby rainforest site, where L. nannotis was more negatively affected by chytridiomycosis. We hypothesize this lack of canopy cover allowed the rocks on which frogs perched to warm up, thereby slowing growth and

  6. Pesticides in amphibian habitats of Central and Northern California, USA

    Science.gov (United States)

    Fellers, Gary M.; Sparling, W; McConnell, Laura; Kleeman, Patrick M.; Drakeford, Leticia

    2013-01-01

    Previous studies have indicated that toxicity from pesticide exposure may be contributing to amphibian declines in California and that atmospheric deposition could be a primary pathway for pesticides to enter amphibian habitats. We report on a survey of California wetlands sampled along transects associated with Lassen Volcanic National Park, Lake Tahoe, Yosemite National Park, and Sequoia National Park. Each transect ran from the Pacific coast to the Cascades or Sierra Nevada mountains. Pacific chorus frogs (Pseudacris regilla), water, and sediment were collected from wetlands in 2001 and 2002. Twenty-three pesticides were found in frog, water, or sediment samples. Six contaminants including trifluralin, α-endosulfan, chlordanes, and trans-nonachlor were found in adult P. regilla. Seventeen contaminants were found in sediments, including endosulfan sulfate, chlordanes, 1-chloro-4-[2,2-dichloro-1-(4-chlorophenyl)ethenyl]benzene (4,4′-DDE), and chlorpyrifos. The mean number of chemicals detected per pond in sediments was 2.4 (2.5, standard deviation). In water, 17 chemicals were detected, with β-endosulfan being present in almost all samples. Trifluralin, chlordanes, and chlorpyrifos were the next most common. The mean number of chemicals in water per pond was 7.8 (2.9). With the possible exception of chlorpyrifos oxon in sediments and total endosulfans, none of the contaminants exceeded known lethal or sublethal concentrations in P. regilla tissue. Endosulfans, chlorpyrifos, and trifluralin were associated with historic and present day population status of amphibians. Cholinesterase, an essential neurological enzyme that can be depressed by certain pesticides, was reduced in tadpoles from areas with the greatest population declines.

  7. Relationship Between Landscape Character, UV Exposure, and Amphibian Decline

    Science.gov (United States)

    O'Reilly, C. M.; Brooks, P. D.; Corn, P. S.; Muths, E.; Campbell, D. H.; Diamond, S.; Tonnessen, K.

    2001-12-01

    Widespread reports of amphibian declines have been considered a warning of large-scale environmental degradation, yet the reasons for these declines remain unclear. This study suggests that exposure to ultraviolet radiation may act as an environmental stressor that affects population breeding success or susceptibility to disease. Ultraviolet radiation is attenuated by dissolved and particulate compounds in water, which may be of either terrestrial or aquatic origin. UV attenuation by dissolved organic carbon (DOC) is primarily due to compounds in the fulvic acid fraction, which originate in soil environments. These terrestrially-derived fulvic acids are transported to during hydrologic flushing events such as snowmelt and episodic precipitation and play an important role in controlling UV exposure in surface waters. As part of a previously published project, amphibian surveys were conducted at seventeen sites in Rocky Mountain National Park both during, and subsequent to, a three-year drought (1988 - 1990). During this period, ten sites lost one amphibian species, while only one site gained a previously unreported species. One possible explanation for these localized species losses is increased exposure to UV radiation, mediated by reduced terrestrial DOC inputs during dry periods. Several subsequent years of water chemistry data showed that the sites with documented species losses were characterized by a range of DOC concentrations, but tended to have a greater proportion of terrestrial DOC than sites that did not undergo species loss. This suggests that terrestrial inputs exert a strong control on DOC concentrations that may influence species success. We used physical environmental factors to develop a classification scheme for these sites. There are many physical factors that can influence terrestrial DOC inputs, including landscape position, geomorphology, soil type, and watershed vegetation. In addition, we considered the possible effects on internal aquatic

  8. Experimental canopy removal enhances diversity of vernal pond amphibians.

    Science.gov (United States)

    Skelly, David K; Bolden, Susan R; Freidenburg, L Kealoha

    2014-03-01

    Vernal ponds are often treated as protected environments receiving special regulation and management. Within the landscapes where they are found, forest vegetation frequently dominates surrounding uplands and can grow to overtop and shade pond basins. Two bodies of research offer differing views of the role of forest canopy for vernal pond systems. Studies of landscape conversion suggest that removing forest overstory within uplands can cause local extinctions of amphibians by altering terrestrial habitat or hindering movement. Studies of canopy above pond basins imply an opposite relationship; encroachment of overstory vegetation can be associated with local extinctions potentially via changes in light, thermal, and food resource environments. Unresolved uncertainties about the role of forest canopy reveal significant gaps in our understanding of wetland species distributions and dynamics. Any misunderstanding of canopy influences is simultaneously important to managers because current practices emphasize promoting or conserving vegetation growth particularly within buffers immediately adjacent to ponds. We evaluated this apparent contradiction by conducting a landscape-scale, long-term experiment using 14 natural vernal ponds. Tree felling at six manipulated ponds was limited in spatial scope but was nevertheless effective in increasing water temperature. Compared with eight control ponds, manipulated ponds maintained more amphibian species during five years post-manipulation. There was little evidence that any species was negatively influenced, and the reproductive effort of species for which we estimated egg inputs maintained pretreatment population densities in manipulated compared with control ponds. Overall, our experiment shows that a carefully circumscribed reduction of overhead forest canopy can enhance the capacity of vernal ponds to support wildlife diversity and suggests a scale dependence of canopy influences on amphibians. These findings have

  9. Influence of Physiological Stress on Nutrient Stoichiometry in Larval Amphibians.

    Science.gov (United States)

    Kirschman, Lucas J; Haslett, Savhannah; Fritz, Kelley A; Whiles, Matt R; Warne, Robin W

    2016-01-01

    Exposure to environmental stressors alters animal phenotypes as well as nutrient metabolism, assimilation, and excretion. While stress-induced shifts in nutrient processes are known to alter organismal carbon (C) and nitrogen (N) stoichiometry, there has been little exploration of how environmental factors influence phosphorous (P). A better understanding of how P cycling varies with animal physiological state may provide insight into across-scale processes, because P is essential to animal function and ecological processes such as production and decomposition. We tested the effects of predator stress and exogenous glucocorticoids on C∶N∶P stoichiometry of larval amphibians. Glucocorticoids altered nutrient stoichiometry, apparently by modulating ossification and renal function. This reduced whole-body P and significantly increased N∶P. Additionally, elevated glucocorticoids caused a long-term reduction in P excretion. This reduction may reflect an initial unmeasured loss of P that glucocorticoids induce over acute timescales. In contrast, exposure to predator cues had no effect on larval C∶N∶P stoichiometry, which highlights that different stressors have varied effects on the endocrine stress response. Predation, in particular, is ubiquitous in the environment; thus, larvae responding to predators have conserved mechanisms that likely prevent or minimize physiological disruption. These results demonstrate the differing physiological roles of N and P, distinct nutrient demands associated with amphibian metamorphosis, and the contrasting effects that different environmental factors have on the physiological stress response. Our results also suggest that anthropogenic changes to the environment that induce chronic stress in amphibians could affect the biogeochemistry of nutrient-poor environments where they may act as keystone species.

  10. Amphibians and reptiles of the state of Coahuila, Mexico, with comparison with adjoining states.

    Science.gov (United States)

    Lemos-Espinal, Julio A; Smith, Geoffrey R

    2016-01-01

    We compiled a checklist of the amphibians and reptiles of the state of Coahuila, Mexico. The list comprises 133 species (24 amphibians, 109 reptiles), representing 27 families (9 amphibians, 18 reptiles) and 65 genera (16 amphibians, 49 reptiles). Coahuila has a high richness of lizards in the genus Sceloporus. Coahuila has relatively few state endemics, but has several regional endemics. Overlap in the herpetofauna of Coahuila and bordering states is fairly extensive. Of the 132 species of native amphibians and reptiles, eight are listed as Vulnerable, six as Near Threatened, and six as Endangered in the IUCN Red List. In the SEMARNAT listing, 19 species are Subject to Special Protection, 26 are Threatened, and three are in Danger of Extinction. Coahuila is home to several species of conservation concern, especially lizards and turtles. Coahuila is an important state for the conservation of the native regional fauna.

  11. Expansion of amphibian intronless interferons revises the paradigm for interferon evolution and functional diversity.

    Science.gov (United States)

    Sang, Yongming; Liu, Qinfang; Lee, Jinhwa; Ma, Wenjun; McVey, D Scott; Blecha, Frank

    2016-06-30

    Interferons (IFNs) are key cytokines identified in vertebrates and evolutionary dominance of intronless IFN genes in amniotes is a signature event in IFN evolution. For the first time, we show that the emergence and expansion of intronless IFN genes is evident in amphibians, shown by 24-37 intronless IFN genes in each frog species. Amphibian IFNs represent a molecular complex more complicated than those in other vertebrate species, which revises the established model of IFN evolution to facilitate re-inspection of IFN molecular and functional diversity. We identified these intronless amphibian IFNs and their intron-containing progenitors, and functionally characterized constitutive and inductive expression and antimicrobial roles in infections caused by zoonotic pathogens, such as influenza viruses and Listeria monocytogenes. Amphibians, therefore, may serve as overlooked vectors/hosts for zoonotic pathogens, and the amphibian IFN system provides a model to study IFN evolution in molecular and functional diversity in coping with dramatic environmental changes during terrestrial adaption.

  12. Evolutionary landscape of amphibians emerging from ancient freshwater fish inferred from complete mitochondrial genomes.

    Science.gov (United States)

    Wang, Xiao-Tong; Zhang, Yan-Feng; Wu, Qian; Zhang, Hao

    2012-05-01

    It is very interesting that the only extant marine amphibian is the marine frog, Fejervarya cancrivora. This study investigated the reasons for this apparent rarity by conducting a phylogenetic tree analysis of the complete mitochondrial genomes from 14 amphibians, 67 freshwater fishes, four migratory fishes, 35 saltwater fishes, and one hemichordate. The results showed that amphibians, living fossil fishes, and the common ancestors of modern fishes are phylogenetically separated. In general, amphibians, living fossil fishes, saltwater fishes, and freshwater fishes are clustered in different clades. This suggests that the ancestor of living amphibians arose from a type of primordial freshwater fish, rather than the coelacanth, lungfish, or modern saltwater fish. Modern freshwater fish and modern saltwater fish were probably separated from a common ancestor by a single event, caused by crustal movement.

  13. Parallels in amphibian and bat declines from pathogenic fungi.

    Science.gov (United States)

    Eskew, Evan A; Todd, Brian D

    2013-03-01

    Pathogenic fungi have substantial effects on global biodiversity, and 2 emerging pathogenic species-the chytridiomycete Batrachochytrium dendrobatidis, which causes chytridiomycosis in amphibians, and the ascomycete Geomyces destructans, which causes white-nose syndrome in hibernating bats-are implicated in the widespread decline of their vertebrate hosts. We synthesized current knowledge for chytridiomycosis and white-nose syndrome regarding disease emergence, environmental reservoirs, life history characteristics of the host, and host-pathogen interactions. We found striking similarities between these aspects of chytridiomycosis and white-nose syndrome, and the research that we review and propose should help guide management of future emerging fungal diseases.

  14. Turtle isochore structure is intermediate between amphibians and other amniotes.

    Science.gov (United States)

    Chojnowski, Jena L; Braun, Edward L

    2008-10-01

    Vertebrate genomes are comprised of isochores that are relatively long (>100 kb) regions with a relatively homogenous (either GC-rich or AT-rich) base composition and with rather sharp boundaries with neighboring isochores. Mammals and living archosaurs (birds and crocodilians) have heterogeneous genomes that include very GC-rich isochores. In sharp contrast, the genomes of amphibians and fishes are more homogeneous and they have a lower overall GC content. Because DNA with higher GC content is more thermostable, the elevated GC content of mammalian and archosaurian DNA has been hypothesized to be an adaptation to higher body temperatures. This hypothesis can be tested by examining structure of isochores across the reptilian clade, which includes the archosaurs, testudines (turtles), and lepidosaurs (lizards and snakes), because reptiles exhibit diverse body sizes, metabolic rates, and patterns of thermoregulation. This study focuses on a comparative analysis of a new set of expressed genes of the red-eared slider turtle and orthologs of the turtle genes in mammalian (human, mouse, dog, and opossum), archosaurian (chicken and alligator), and amphibian (western clawed frog) genomes. EST (expressed sequence tag) data from a turtle cDNA library enriched for genes that have specialized functions (developmental genes) revealed using the GC content of the third-codon-position to examine isochore structure requires careful consideration of the types of genes examined. The more highly expressed genes (e.g., housekeeping genes) are more likely to be GC-rich than are genes with specialized functions. However, the set of highly expressed turtle genes demonstrated that the turtle genome has a GC content that is intermediate between the GC-poor amphibians and the GC-rich mammals and archosaurs. There was a strong correlation between the GC content of all turtle genes and the GC content of other vertebrate genes, with the slope of the line describing this relationship also

  15. Snake venomics and antivenomics of the arboreal neotropical pitvipers Bothriechis lateralis and Bothriechis schlegelii.

    Science.gov (United States)

    Lomonte, Bruno; Escolano, José; Fernández, Julián; Sanz, Libia; Angulo, Yamileth; Gutiérrez, José María; Calvete, Juan J

    2008-06-01

    We report the comparative proteomic characterization of the venoms of two related neotropical arboreal pitvipers from Costa Rica of the genus Bothriechis, B. lateralis (side-striped palm pit viper) and B. schlegelii (eyelash pit viper). The crude venoms were fractionated by reverse-phase HPLC, followed by analysis of each chromatographic fraction by SDS-PAGE, N-terminal sequencing, MALDI-TOF mass fingerprinting, and collision-induced dissociation tandem mass spectrometry of tryptic peptides. The venom proteomes of B. lateralis and B. schlegelii comprise similar number of distinct proteins belonging, respectively, to 8 and 7 protein families. The two Bothriechis venoms contain bradykinin-potentiating peptides (BPPs), and proteins from the phospholipase A 2 (PLA 2), serine proteinase, l-amino acid oxidase (LAO), cysteine-rich secretory protein (CRISP), and Zn (2+)-dependent metalloproteinase (SVMP) families, albeit each species exhibit different relative abundances. Each venom also contains unique components, for example, snake venom vascular endothelial growth factor (svVEGF) and C-type lectin-like molecules in B. lateralis, and Kazal-type serine proteinase inhibitor-like proteins in B. schlegelii. Using a similarity coefficient, we estimate that the similarity of the venom proteins between the two Bothriechis taxa may be venom compositions, in spite of the fact that both species have evolved to adapt to arboreal habits. The major toxin families of B. lateralis and B. schlegelii are SVMP (55% of the total venom proteins) and PLA 2 (44%), respectively. Their different venom toxin compositions provide clues for rationalizing the distinct signs of envenomation caused by B. schlegelii and B. lateralis. An antivenomic study of the immunoreactivity of the Instituto Clodomiro Picado (ICP) polyvalent antivenom toward Bothriechis venoms revealed that l-amino acid oxidase and SVMPs represent the major antigenic protein species in both venoms. Our results provide a ground for

  16. Report on the changes of LD50 of Bee venom Herbal Acupuncture

    Directory of Open Access Journals (Sweden)

    Ki Rok Kwon

    2005-02-01

    Full Text Available Objectives : This experiment was conducted to reevaluate LD50 of Korean bee venom acupuncture as many changes have occurred over the years. Methods : ICR mice were used as the experiment animals and bee venom acupuncture was manufactured under the protocols of Korean Institute of herbal Acupuncture. Based on the previous reports, experiment was divided into pre and main sections. Results : 1. Presumed LD50 value is at 5.25mg/kg. 2. Deaths of experiment animals occurred within 48 hours. 3. Reduced toxicity of the bee venom acupuncture is likely to be the results of more refined manufacturing process and production. Conclusion : Comparing with the values of the previous results, toxicity of the bee venom acupuncture showed significant changes and more accurate findings on LD50 value must be accomplished to lead further studies on the bee venom acupuncture.

  17. Electrospray liquid chromatography/mass spectrometry fingerprinting of Acanthophis (death adder) venoms: taxonomic and toxinological implications.

    Science.gov (United States)

    Fry, Bryan G; Wickramaratna, Janith C; Hodgson, Wayne C; Alewood, Paul F; Kini, R M; Ho, Hao; Wüster, Wolfgang

    2002-01-01

    Death adders (genus Acanthophis) are unique among elapid snakes in both morphology and venom composition. Despite this genus being among the most divergent of all elapids, the venom has been historically regarded as relatively quite simple. In this study, liquid chromatography/mass spectrometry (LC/MS) analysis has revealed a much greater diversity in venom composition, including the presence of molecules of novel molecular weights that may represent a new class of venom component. Furthermore, significant variation exists between species and populations, which allow for the LC/MS fingerprinting of each species. Mass profiling of Acanthophis venoms clearly demonstrates the effectiveness of this technique which underpins fundamental studies ranging from chemotaxonomy to drug design.

  18. Partial purification of box jellyfish (Chironex fleckeri) nematocyst venom isolated at the beachside.

    Science.gov (United States)

    Bloom, D A; Burnett, J W; Alderslade, P

    1998-08-01

    Chironex fleckeri, the northern Australian box jellyfish produces one of, if not, the most potent animal venoms. Study of the venom has been hampered by the limits of the animals' range and the venom's thermolability. Using retained lethality and native polyacrylamide gel electrophoresis (NPAGE), we show that lyophilization of autolysis isolated nematocysts is an effective method of transporting the venom. In addition, Sephadex G-200 chromatography, spin concentration, and NPAGE fail to demonstrate the presence of a 600 kDa protein to which the bulk of the lethal activity has been ascribed. Sodium dodecyl sulfate capillary electrophoresis of crude venom yields several protein bands with a molecular weight range of 30-200 kDa. Freeze-thaw studies show a loss of activity and NPAGE bands after two freeze thaw cycles.

  19. Comparative analysis of methods for concentrating venom from jellyfish Rhopilema esculentum Kishinouye

    Science.gov (United States)

    Li, Cuiping; Yu, Huahua; Feng, Jinhua; Chen, Xiaolin; Li, Pengcheng

    2009-02-01

    In this study, several methods were compared for the efficiency to concentrate venom from the tentacles of jellyfish Rhopilema esculentum Kishinouye. The results show that the methods using either freezing-dry or gel absorption to remove water to concentrate venom are not applicable due to the low concentration of the compounds dissolved. Although the recovery efficiency and the total venom obtained using the dialysis dehydration method are high, some proteins can be lost during the concentrating process. Comparing to the lyophilization method, ultrafiltration is a simple way to concentrate the compounds at high percentage but the hemolytic activities of the proteins obtained by ultrafiltration appear to be lower. Our results suggest that overall lyophilization is the best and recommended method to concentrate venom from the tentacles of jellyfish. It shows not only the high recovery efficiency for the venoms but high hemolytic activities as well.

  20. Comparative analysis of methods for concentrating venom from jellyfish Rhopilema esculentum Kishinouye

    Institute of Scientific and Technical Information of China (English)

    YU Huahua; FENG Jinhua; CHEN Xiaolin; LI Pengcheng

    2009-01-01

    In this study, several methods were compared for the efficiency to concentrate venom from the tentacles of jellyfish Rhopilema esculentum Kishinouye. The results show that the methods using either freezing-dry or gel absorption to remove water to concentrate venom are not applicable due to the low concentration of the compounds dissolved. Although the recovery efficiency and the total venom obtained using the dialysis dehydration method are high, some proteins can be lost during the concentrating process. Comparing to the lyophilization method, ultrafiltration is a simple way to concentrate the compounds at high percentage but the hemolytic activities of the proteins obtained by ultrafiltration appear to be lower. Our results suggest that overall lyophilization is the best and recommended method to concentrate venom from the tentacles of jellyfish. It shows not only the high recovery efficiency for the venoms but high hemolytic activities as well.