Publications

TitleAbstractYear
Filter
PMID
Filter
haematopoietic malignancies in zoo animals.myelogenous leukaemia was found in a russell's viper, a honduran milk snake, a marine toad, a byrne's marsupial mouse and an african hedgehog. lymphocytic leukaemia was present in a broad banded copperhead and an indian lion. visceral lymphomatosis was observed in a snowy owl.19921556254
molecular cloning and sequence analysis of cdnas for metalloproteinases from broad-banded copperhead agkistrodon contortrix laticinctus.the cdna sequences of two related genes coding for metalloproteinases from a venom gland library of agkistrodon contortrix laticinctus have been determined. the aclpreh cdna codes for a 220-amino acid zinc-dependent hemorrhagic metalloproteinase, and the predicted sequence is in agreement with the n-terminal sequence of the previously purified protein. aclpref cdna sequence predicts a 222-amino acid molecule having strong similarity to fibrolase, a fibrinolytic enzyme isolated from a. contortrix ...19957793974
cdna cloning and sequence analysis of a lysine-49 phospholipase a2 myotoxin from agkistrodon contortrix laticinctus snake venom.a cdna clone (aclpremt1) for a k49 phospholipase a2 (pla2) myotoxin from agkistrodon contortrix laticinctus snake venom was isolated from a venom gland library and sequenced. the aclpremt1 cdna is 734 bp in length and has an open reading frame of 414 bp. it codes for a k49 phospholipase a2 with 121 amino acid residues. the sequence of the first 20 amino acid residues of the predicted mature protein matches exactly with the n-terminal sequence of the purified myotoxin. comparison of the aclpremt1 ...19968579368
the role of extracellular ions in the pathogenesis of myonecrosis induced by a myotoxin isolated from broad-banded copperhead (agkistrodon contortrix laticinctus) venom.pathological changes in murine skeletal muscle cells induced by acl (agkistrodon contortrix laticinctus, broad-banded copperhead) myotoxin in vivo were compared to pathological changes induced by an influx of ca2+ and other ions into cut skeletal muscle cells in vitro in the absence of myotoxin. in vivo, acl myotoxin induced a rapid myonecrosis characterized by densely clumped myofibrils in the cytoplasm. in vitro, this pathological change was not produced by incubating skeletal muscle cells in ...19948061942
cross-reactivities of monoclonal antibodies to a myotoxin from the venom of the broad-banded copperhead (agkistrodon contortrix laticinctus).a panel of murine monoclonal antibodies (mabs) specific for a 14,500 mol. wt myotoxin of agkistrodon contortrix laticinctus (broad-banded copperhead) venom was produced by cell fusion using the purified toxin as immunogen. the mabs were used in immunoblotting and elisa experiments to determine their immunological cross-reactivities. the three mabs used in this study showed different immunoblotting and elisa patterns when they were tested against 43 related and unrelated venom samples, indicating ...19937505491
expression, refolding, and activity of a recombinant nonhemorrhagic snake venom metalloprotease.snake venoms are rich sources of proteases that strongly affect the vascular system, by promoting blood coagulation, hemorrhage, and fibrinolysis. hemorrhagic activity is mostly due to the enzymatic action of metalloproteases on capillary basement membrane components, such as collagen iv, laminin, and fibronectin. a few low-molecular-weight snake venom metalloproteases (svmp) have been described as being devoid of hemorrhagic activity, but they have strong direct-acting fibrinolytic activity tha ...200010833388
isolation of a hemorrhagic toxin from the venom of agkistrodon contortrix laticinctus (broad-banded copperhead) and pathogenesis of the hemorrhage induced by the toxin in mice.1. a hemorrhagic toxin was isolated from the venom of agkistrodon contortrix laticinctus (broad-banded copperhead) by sephacryl s-200 hr column chromatography followed by high performance chromatography on waters deae 5pw and protein pak 125 columns. 2. homogeneity was determined by the presence of a single band in acrylamide gel electrophoresis with silver staining. 3. acl hemorrhagic toxin i has a molecular weight of about 29,000, is slightly acidic, and is a metalloprotease with activity towa ...19938444323
development of an enzyme-linked immunosorbent assay (elisa) for identification of venoms from snakes in the agkistrodon genus.an enzyme-linked immunosorbent assay (elisa) using a purified myotoxin from the venom of agkistrodon contortrix laticintus (broad-banded copperhead) as immunogen was developed for potential use in the identification of envenomation by snakes belonging to the genus agkistrodon native to north america. the specificity of the assay was tested using a total of 43 venom samples from snakes of diverse geographic locations. venom samples used for cross-reactivity determination represent eight snake fam ...19947886691
sequence analysis of lys49 phospholipase a2 myotoxins: a highly conserved class of proteins.a cdna clone coding for a putative lys49 phospholipase a2 myotoxin (acl myotoxin) from agkistrodon contortrix laticinctus was isolated from a venom gland library and sequenced. the sequence of the first 40 amino acid residues of the predicted protein matches exactly with the n-terminal sequence of the purified myotoxin. sequence comparison of the predicted sequence of acl myotoxin and other lys49 and asp49 phospholipase a2 enzymes shows that the lys49 phospholipase toxins form a highly conserved ...20169027979
preliminary x-ray crystallographic data for a myotoxin from agkistrodon contortrix laticinctus (broad-banded copperhead) venom.a type ii phospholipase a2 myotoxin from agkistrodon contortrix laticinctus was purified to homogeneity and crystallized. the protein had only myotoxic activity. x-ray diffraction quality crystals were obtained by the hanging drop vapour diffusion method from a crystallization solution containing 2.0 m ammonium sulphate. x-ray data were collected to a resolution of 2.3 a, and the crystals are fully characterized.19979133716
lys49 phospholipase a2 myotoxins lyse cell cultures by two distinct mechanisms.three lys49 phospholipase a2 (pla2) myotoxins from agkistrodon contortrix laticinctus (aclmt), bothrops jararacussu (bothropstoxin-i) and bothrops asper (myotoxin ii) snake venoms are enzymatically inactive on artificial substrates, yet addition of these toxins to cell cultures causes the release of fatty acids derived from the hydrolysis of membrane phospholipids. bothropstoxin-i treated with p-bromophenacyl bromide is no longer enzymatically active on cell cultures, suggesting the toxin, not t ...19989792171
ability of wedelolactone, heparin, and para-bromophenacyl bromide to antagonize the myotoxic effects of two crotaline venoms and their pla2 myotoxins.we examined the ability of wedelolactone, heparin and para-bromophenacyl bromide to antagonize the myotoxic activity in mice of venoms from crotalus viridis viridis and agkistrodon contortrix laticinctus and two phospholipase a2 myotoxins, cvv myotoxin and acl myotoxin, isolated from them. myotoxicity was measured by the increase in plasma creatine kinase (ck) activity at two hours and histological changes in extensor digitorum longus muscle (edl) at three hours after injection of the test solut ...19999920492
neutralization of edema, hemorrhage and myonecrosis induced by north american crotalid venoms in simulated first-aid treatments.venoms of the broad-banded copperhead (agkistrodon contortrix laticinctus, acl) and the prairie rattlesnake (crotalus viridis viridis, cvv), like other crotalid venoms, cause severe local tissue damage such as edema, hemorrhage and myonecrosis. antivenom therapy is not very effective in neutralizing this local tissue damage, and such observations support the need for an effective first-aid regimen aimed at minimizing local tissue reactions. some of the local tissue damage induced by these venoms ...199910082163
long-term regeneration of fast and slow murine skeletal muscles after induced injury by acl myotoxin isolated from agkistrodon contortrix laticinctus (broad-banded copperhead) venom.the aim of the present work was to analyze the regenerated muscle types i and ii fibers of the soleus and gastrocnemius muscles of mice, 8 months after damage induced by acl myotoxin (aclmt). animals received 5 mg/kg of aclmt into the subcutaneous lateral region of the right hind limb, near the achilles tendon; contralateral muscles received saline. longitudinal and cross sections (10 microm) of frozen muscle tissue were evaluated. eight months after aclmt injection, both muscle types i and ii f ...199910203259
copperhead envenomations: clinical profiles of three different subspecies.copperhead envenomation cases reported in the literature frequently lack identification of the subspecies of copperhead responsible for the envenomation. whether subspecific identity would be useful in predicting possible different toxicity profiles may have clinical relevance. we report here the clinical profiles from envenomations involving 3 different subspecies of captive adult copperhead snakes--the southern copperhead (agkistrodon contortrix contortrix), the northern copperhead (agkistrodo ...199910349703
isolation and structural characterization of a cytotoxic l-amino acid oxidase from agkistrodon contortrix laticinctus snake venom: preliminary crystallographic data.we have purified a cytotoxic l-amino acid oxidase (lao) from agkistrodon contortrix laticinctus snake venom by means of superdex-200 gel filtration, followed by phenyl-sepharose cl-4b chromatography. the purified enzyme (acl lao) is a dimer on gel filtration, with a m(r) of 60,000 for the monomer as estimated by sds-page. lao activity was tested against 15 amino acids, but only 9 were oxidized by the enzyme, suggesting that it presents some degree of specificity. acl lao has apoptosis-inducing a ...199910441379
expression of an active recombinant lysine 49 phospholipase a(2) myotoxin as a fusion protein in bacteria.acl myotoxin (aclmt) is a k49 phospholipase a(2)-like protein isolated from the venom of the snake agkistrodon contortrix laticinctus (broad-banded copperhead) that induces necrosis of skeletal muscle. we have previously cloned and sequenced the cdna coding for aclmt from a venom gland cdna library. in order to perform structure and function studies, we have developed an expression system for production of aclmt as a fusion protein with maltose binding protein (mbp) from the periplasm of bacteri ...200111478968
different sensitivity of fast- and slow-twitch muscles to some snake venoms and myotoxins.we examined the effect of some crude snake venoms, isolated toxins and non-specific cytotoxic agents on isolated extensor digitorum longus (edl) and soleus (sol) muscles of the mouse. the muscles were continuously perfused with a physiological saline solution. crude venoms from crotalus viridis viridis, agkistrodon contortrix laticinctus and notechis scutatus scutatus were tested at a concentration of 25-50 micrograms ml-1. the increase in the rate of creatine kinase (ck) release (above basal le ...19968817811
regeneration and change of muscle fiber types after injury induced by a hemorrhagic fraction isolated from agkistrodon contortrix laticinctus venom.tibialis anterior (ta) muscles of rats were evaluated 3h, 3 and 30days after intramuscular injection of acl hemorrhagic toxin i (aclht-i, 5mg/kg), partially purified from the venom of agkistrodon contortrix laticinctus. contralateral muscles were injected with saline. three hours after aclht-1 injection: presence of hemorrhagic areas and myonecrotic muscle fibers. three days: injured muscles showed areas in regeneration, some regions with delay of regeneration and bundles of normal fibers. an in ...200111072042
isolation of a myotoxin from the venom of agkistrodon contortrix laticinctus (broad-banded copperhead) and pathogenesis of myonecrosis induced by it in mice.a myotoxin was isolated from the venom of the broad-banded copperhead (agkistrodon contortrix laticinctus) by hplc using anion and cation exchange chromatography. the toxin has a mol. wt of approximately 14,000 and has a pi greater than 9. it does not have phospholipase a activity, but does induce myonecrosis of skeletal muscle cells characterized by a hypercontraction of myofilaments. electron microscopic analysis showed that the myotoxin appears to disrupt the sarcolemma of skeletal muscle cel ...19938470130
analysis of a cdna sequence encoding a novel member of the snake venom metalloproteinase, disintegrin-like, cysteine-rich (mdc) protein family from agkistrodon contortrix laticinctus.in this paper, we present a cdna sequence encoding a full-length precursor form of a new member (acld) of the metalloproteinase-disintegrin-like protein family from the venom glands of agkistrodon contortrix laticinctus (broad-banded copperhead) snake. comparison of the deduced amino acid sequence of acld with those of other members of the metalloproteinase-disintegrin protein family from both mammalian and snake venom origin suggests that some conserved residues may be involved in processing of ...19979392519
injury and recovery of fast and slow skeletal muscle fibers affected by acl myotoxin isolated from agkistrodon contortrix laticinctus (broad-banded copperhead) venom.the response of different types of skeletal muscle fibers to a snake venom pla2 myotoxin was tested in vivo by injecting acl myotoxin (aclmt) into mice. both the soleus (slow-twitch) and gastrocnemius (fast-twitch) were examined at different time periods (3 h, 3 and 21 d) after the injection. all animals received 5 mg/kg myotoxin into the subcutaneous lateral region of the right hind limb, near the achilles tendon; contralateral muscles were used as controls. cross-sections (10 microm) of frozen ...19989690794
Displaying items 1 - 22 of 22