Venomous Reptiles Research Articles

Book and media review

Auerbach, PS Mosby, 2007 2336 pages, $199.00 ISBN 0323032281 Auerbach has recently released the fifth edition of his text, Wilderness Medicine. The bold mission statement of this book is stated on its back cover: to help the reader “manage any medical emergency you encounter in the great outdoors!” We are happy to report, “mission accomplished!” Easily doubling the size of other wilderness medicine texts, and with an impressive array of contributors, Auerbach has long been considered the “Bible” of wilderness medicine. To reflect the current growth and expansion in the field of wilderness medicine, this fifth edition contains several additional sections not included in the prior edition. Also, original chapters have been expanded. The text is organized into 13 sections, based on types of injury, environments encountered, equipment, and patient presentations. Each topic is presented clearly and is easily followed, with consistently strong authorship throughout. Nearly all of the many illustrations are full color and relevant to the topic at hand, and numerous tables summarize frequently needed information in easy to reference formats. One of the most impressive new additions to the text is a chapter on bandaging and taping. This section contains a large number of full-color illustrations and photos for step-by-step guides to these common procedures. Figure 18-2, for example, uses 11 large photographs to illustrate the proper technique for wrapping an ankle, and is clear, color-coded, and simple to follow. The high-quality illustrations persist throughout the text, from instruction on proper technique for rescue knots, to creating a litter or stretcher, to identification of common venomous reptiles. Existing chapters have been updated as well. This is evident beginning with the first chapter on high-altitude medicine, which contains additional figures that diagram the nitric oxide mechanism, and relate acclimatization to acute mountain sickness prevalence, as well as additions to the chapter text that further explain high-altitude physiology. There is also considerably more coverage given to the effects of wilderness situations on pre-existing medical conditions. Accompanying the text is a DVD-ROM containing the figures located throughout the text. These are easily found by chapter heading, and may be saved into picture or PowerPoint© files, a very useful tool when preparing lectures. For those wishing to further pursue a topic, the disc also contains the original material and research used in writing the chapters referenced in its Medline© format. However, one limitation is that these citations, probably in deference to text length and size constraints, are not included in the printed version of this edition. Overall, Wilderness Medicine remains an excellent reference text for any clinician planning to venture into the outdoors, or in need of a thorough review of any given wilderness topic. It is well suited as a general text for a range of readers from academicians to students and residents. At greater than 2300 pages and over 10 pounds, the text is too cumbersome to be effectively used as a field manual, although a much smaller field edition does exist. In addition, certain sections such as the chapters on survival at sea and volcanic eruptions make for interesting reading but only minimally address actual medical care or preparedness. A few rare criticisms aside, this text remains an excellent resource for any practitioner preparing for a wilderness experience, an encompassing reference text on the subject matter, and an engaging read that continues to further the reader’s interest in the various topics of wilderness medicine.

Novel cysteine-rich secretory protein in the buccal gland secretion of the parasitic lamprey, Lethenteron japonicum

Lampreys are one of the most primitive vertebrates diverged some 500 million years ago. It has long been known that parasitic lampreys secrete anticoagulant from their buccal glands and prevent blood coagulation of host fishes. We found two major protein components of 160 and 26 kDa in the buccal gland secretion of parasitic river lamprey, Lethenteron japonicum. The larger protein was identified as river lamprey plasma albumin. The complete primary structure of the 26-kDa protein was determined by protein and cDNA analysis. It belonged to the cysteine-rich secretory protein (CRISP) superfamily that includes recently identified reptile venom ion-channel blockers. Lamprey CRISP blocked depolarization-induced contraction of rat-tail arterial smooth muscle, but showed no effect on caffeine-induced contraction. The result suggests that lamprey CRISP is an L-type Ca 2+-channel blocker and may act as a vasodilator, which facilitates the parasite to feed on the host’s blood. The lamprey CRISP protein contains a number of short insertions throughout the sequence, when aligned with reptilian venom CRISP proteins, probably due to the large evolutionary distance between the Agnatha and the Reptilia, and may represent a novel class of venom CRISP family proteins.

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

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 Solorzano's (2004) Serpientes de Costa Rica. Recently, McCranie, Wilson and Kohler inspire us with a volume on the species of amphibians and reptiles that inhabit the department of Islas de la Bahia, in the Caribbean sea of Honduras.

Isolation and cloning of exendin precursor cDNAs from single samples of venom from the Mexican beaded lizard ( Heloderma horridum) and the Gila monster ( Heloderma suspectum)

Reptile venoms are complex cocktails of bioactive molecules, including peptides. While the drug discovery potential of most species remains unrealized, many are endangered and afforded protection under international treaties. In this study, we describe how potential clinically important bioactive peptides and their corresponding mRNAs can be structurally characterized from single, small samples of reptile venom. The potential type-2 diabetes therapeutics, exendin-3 and exendin-4, from the Mexican beaded lizard ( Heloderma horridum) and the Gila monster ( Heloderma suspectum), respectively, have been characterized at both protein and nucleic acid levels to illustrate the efficacy of the technique and its contribution to biodiversity conservation.

The New World Venomous Reptiles Get the Treatment They DeserveA review of The Venomous Reptiles of the Western Hemisphere, Volumes I and II. Comstock Books in Herpetology. By Jonathan A Campbell and , William W Lamar, with contributions by , Edmund D Brodie III, Edmund D Brodie, Jr, Ronald L Gutberlet, Jr, Michael B Harvey, Robert Norris, David A Warrell,

Previous articleNext article No AccessThe New World Venomous Reptiles Get the Treatment They Deserve A review of The Venomous Reptiles of the Western Hemisphere, Volumes I and II. Comstock Books in Herpetology. By Jonathan A Campbell and , William W Lamar, with contributions by , Edmund D Brodie III, Edmund D Brodie, Jr, Ronald L Gutberlet, Jr, Michael B Harvey, Robert Norris, David A Warrell, and , Vinícius Xavier da Silva. Comstock Publishing Associates. Ithaca (New York): Cornell University Press. $149.95 (two‐volume set). (I) xix + 475 p + 751 pl; ill. (II) xv + pp 477–870 + 749 pl; ill.; Index to Volumes I and II (28 pages). ISBN: 0‐8014‐4141‐2. 2004.Larry David WilsonLarry David WilsonDepartment of Biology, Miami‐Dade College Miami, Florida 33176‐3393 USA [email protected] Search for more articles by this author Department of Biology, Miami‐Dade College Miami, Florida 33176‐3393 USA [email protected]PDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The Quarterly Review of Biology Volume 80, Number 2June 2005 Published in association with Stony Brook University Article DOIhttps://doi.org/10.1086/433059 Views: 3Total views on this site Copyright © 2005 by The University of Chicago. All rights reserved.PDF download Crossref reports no articles citing this article.

The Venomous Reptiles of the Western Hemisphere

The Venomous Reptiles of the Western Hemisphere

The venomous reptiles of the Western Hemisphere

The venomous reptiles of the Western Hemisphere

"Venomous Reptiles of the Western Hemisphere" by Jonathan A. Campbell and William W. Lamar [book review

"Venomous Reptiles of the Western Hemisphere" by Jonathan A. Campbell and William W. Lamar [book review

Fangs, Venom, and Fear Unraveled

The Venomous Reptiles of the Western Hemisphere . by Jonathan A. Campbell and William W. Lamar. Comstock (Cornell University Press), Ithaca, NY, 2004. 2 vols. 962 pp. $149.95, £86.95. ISBN 0-8014-4141-2. This profusely illustrated, comprehensive survey of venomous snakes and lizards of the Americas also includes overviews of mimicry, evolution, and the medical management of snakebites.

SNAKES GET THE HOTS FOR BREAKFAST

For most of us, settling down to digest a hearty breakfast isn't the most eventful part of the day. But for many snakes, every meal is breakfast, and digesting unchewed mouthfuls is probably the most energetic thing they do;their metabolic rates rocket. Knowing that a digesting snake has a souped-up metabolic rate, Glenn Tattersall wondered whether digestively active snakes warm up too? After all snakes are not endothermic; they don't normally generate inner warmth. Heading south to Brazil with an infrared camera,Tattersall decided to put well-fed snakes on the spot, and ask them whether they warmed when fed (p. 579).But when Tattersall arrived at Augusto Abe and Denis Andrade's Rio Claro lab, he didn't find a colony of good-natured snakes waiting to work with him. Instead, he had the pick of a colony of Crotalus durissus South American rattlesnakes, with bad attitudes.Unphased by the prospect of working with the venomous reptiles, Tattersall set about preparing small and large mouse meals ready to feed the snakes; but he hadn't banked on the reptile's contrary character. Some of the snakes tucked into their mice, while others didn't finish their portion, or simply ignored them. But after a day, enough snakes had satisfied their hunger for Tattersall to begin tracking the reptile's body temperatures while they patiently digested their snacks.Over the first few hours, Tattersall didn't see much change through the lens of his infrared camera; the snakes blended in well with the thermal background. But after half a day, the snakes began to glow, and after 24 hours, they were clearly 1.5°C warmer then the background temperature. And when he tested the heat given off by a dead mouse after the same time, the mammal's corpse was stone cold. Tattersall wasn't seeing heat produced by a decaying mouse's body; this was a real increase in the reptile's body temperature, entirely due to the rise in their metabolic rate. Once, he even saw discrete hot spots on a snake's body, perfectly matching the number of mice that the reptile had swallowed the day before.Delighted that the infrared camera had picked up the snake's postprandial hotspots, Tattersall began looking to see if the snakes had any other curious thermal habits. Noticing that the animals always rattled their tails vigorously whenever Simone Brito walked into their room, Tattersall trained the camera on the snake's tails. The shaker muscle lit up with warmth, while the air filled rattle stayed cool.Having found that rattlesnakes warm after a mouthful of mouse, Tattersall and Brito are keen to see whether pythons do too. They explain that when a rattlesnake swallows its prey, the venom that killed the hapless victim often contributes to the snake's digestive task, breaking the rodent down from the inside. Pythons on the other hand, rely entirely on their gastric juices to digest their breakfasts. But as Tattersall had to return to his lab in Canada,Brito has been left wondering whether the python's extra internal effort might raise the snake's temperature even higher.

Unmasking venom gland transcriptomes in reptile venoms

While structural studies of reptile venom toxins can be achieved using lyophilized venom samples, until now the cloning of precursor cDNAs required sacrifice of the specimen for dissection of the venom glands. Here we describe a simple and rapid technique that unmasks venom protein mRNAs present in lyophilized venom samples. To illustrate the technique we have RT-PCR-amplified a range of venom protein transcripts from cDNA libraries derived from the venoms of a hemotoxic snake, the Chinese copperhead ( Deinagkistrodon acutus), a neurotoxic snake, the black mamba ( Dendroaspis polylepis), and a venomous lizard, the Gila monster ( Heloderma suspectum). These include a metalloproteinase and phospholipase A2 from D. acutus, a potassium channel blocker, dendrotoxin K, from D. polylepis, and exendin-4 from H. suspectum. These findings imply that the apparent absence and/or lability of mRNA in complex biological matrices is not always real and paves the way for accelerated acquisition of molecular genetic data on venom toxins for scientific and potential therapeutic purposes without sacrifice of endangered herpetofauna.

Sea snake envenomation

Sea snakes are common venomous reptiles found in the warmer waters of the Pacific and Indian Oceans. The most common circumstance for sea snake bite is an accidental encounter by a fisherman while emptying a fishing net. The venom is extremely toxic and most significant on the nervous and musculoskeletal systems. Significant envenomation occurs in about 20% of bites, with death occurring in about 3% of bites. Death most often occurs from respiratory arrest secondary to neurotoxicity. Myotoxins may cause muscle pain and stiffness and lead to clinically significant rhabdomyolysis and possible acute renal failure. Sea snake bites should all be considered a medical emergency. Immobilization of the victim with compression of the envenomed area is important first aid, followed by transporting the victim to an emergency medical facility. Artificial ventilation and hydration with crystalloid may be important lifesaving maneuvers. Sea snake antivenom may be critical for survival in a significant envenomation.

Venomous Reptiles of North America

Venomous Reptiles of North America

Venomous reptiles of North America

Venomous reptiles of North America

Venomous Reptiles of Latin America

Venomous Reptiles of Latin America

The venomous reptiles of Latin America

The venomous reptiles of Latin America

Biotoxicology of sea snake venoms

Sea snakes are the most abundant venomous reptiles, found throughout the Indian and Pacific Oceans. Divided into two subfamilies, Laticaudinae and Hydrophiinae, all sea snakes are poisonous. Venoms are highly toxic, as indicated by low LD50 values in test animals. Toxic compounds include presynaptic and postsynaptic neurotoxins. Similarities in phylogeny are reflected in immunodiffusion patterns, immunoelectrophoresis, cross-neutralization by antivenin against heterologous venoms, and amino acid composition. The clinical syndrome following a bite is largely neurotoxic and myotoxic, with rare hepatotoxicity and nephrotoxicity. Proper emergency field therapy and timely administration of antivenin can be lifesaving. Hemodialysis may be useful when antivenin is not available.

Molecular weight variations in the diversity of phospholipase A 2 forms in reptile venoms

Reptile venoms exhibit a wide diversity of phospholipase A 2 forms when examined by electrophoretic and chromatographic techniques which separate on the basis of net charge. In principle, diversity in charge among the enzyme forms could result from two type of structural modifications: (i) pretranslational modifications, such as differences in amino acid sequences; (ii) post-translational modifications, such as partial proteolysis or hydrolysis of amide functions of asparagine and glutamine residues. Some types of modifications alter both charge and molecular weigth. A radiolabeling technique has been developed which allows detection of phospholipase A 2 enzymes after electrophoretic separation on the basis of molecular weight in polyacrylamide gels containing sodium dodecylsulfate. Venom preparations were radiolabeled by incubation with p- dodecylphenacylbromide , which was prepared radiolabeled to high specific activity with tritium. The labeling agent was dispersed in phosphatidylcholine liposomes and incubated with venom preparations under conditions of optimal enzyme activity. The preparations were then extracted with ether and hexane to remove substrate and unbound label and subjected to polyacrylamide gel electrophoresis under standard conditions. Protein-bound radiolabel was detected by fluorography and autoradiography. Patterns of labeled species obtained by gel electrophoresis of selected venoms using separation on the basis of charge were similar to the patterns of phospholipase A 2 variants obtained under the same electrophoretic conditions using enzymatic detection in phosphatidylcholine-containing gels. Examination of a variety of snake and lizard venoms using this technique revealed the presence of multiple molecular weight forms of labeled enzymes, but the extent of diversity was less than that observed with the same venoms using separation of phospholipase electrophoretic variants on the basis of charge. The results are consistent with diversity in reptile venom phospholipase A 2 forms being derived from differences in both molecular weight and charge.

Bites of Venomous Reptiles

Bites by venomous reptiles are statistically of minor importance in North America, especially as regards medically significant envenomations. However, they may assume a greater relative incidence in warmer regions and always manage to generate public and professional interest wherever they occur. Unproved and potentially hazardous first-aid and institutional therapies must be subjected to scrutiny in the future. Current research in the area of more specific and less reactive antivenin products is encouraging, and it appears that a consensus approach to the care of the bitten patient is emerging. Physicians are encouraged to consult with regional poison control centers in the care of these patients unless they are well experienced in this unique and complicated area.

Antivenin therapy in the emergency department

Venomous animal injuries constitute a significant medical problem worldwide. It is estimated that 40,000 people die annually from venomous snakebite alone. The total morbidity and mortality due to venomous reptiles, arthropods, and marine animals is unknown. The majority of venomous injuries are found in developing countries where the combination of rural populations, high density venomous animal species, and inadequate medical facilities generate a serious public health problem. While venomous animal injuries are less of a problem in the United States, when they do occur they may become a difficult problem to manage and often a major life threat.‘-” Emergency medicine physicians are likely to be involved wth the diagnosis and management of a venomous injury because of their position at the vanguard of the medical system. As in many other emergent conditions, the initial therapy is extremely important and will influence the final outcome of the envenomation. The definitive treatment of envenomation injuries, especially those due to snakebite, is antivenin