| the effect of several viper venoms on prothrombin padua. | the effect of four viper venoms (oxyuranus scutellatus, notechis scutatus scutatus, echis carinatus, naja nigricollis) on prothrombin padua has been studied. using oxyuranus scutellatus venom and notechis scutatus scutatus venom, prothrombin activity resulted to be moderately decreased similarly to what observed with other one-stage and two-stage methods. on the contrary, using echis carinatus venom a normal level was obtained. no clotting was observed using the naja nigricollis venom, regardles ... | 1975 | 1174715 |
| prothrombin and factor x activating properties of bothrops erythromelas venom. | the enzymatic properties of factor ii (fii) and factor x (fx) activators from bothrops erythromelas venom were investigated. both activators were inhibited by ethylenediaminetetraacetate (edta) and 1,10-phenanthroline, and are thought to be metalloproteinases with molecular weights of 90 kda and 70-90 kda, respectively. the activity of the fii activator in the crude venom was about 30 times greater than that in oxyuranus scutellatus venom and the level of fx activator activity, which was ca2+ io ... | 1992 | 1288438 |
| deaths from snake bite in australia, 1981-1991. | to obtain and analyse data relating to snake bite fatalities in australia. | 1992 | 1453996 |
| isolation and physiological characterization of taicatoxin, a complex toxin with specific effects on calcium channels. | taicatoxin is a new complex oligomeric toxin that was isolated from the venom of the australian taipan snake oxyuranus scutellatus scutellatus. it is composed of three different molecular entities: an alpha-neurotoxin-like peptide of mol. wt 8000, a neurotoxic phospholipase of mol. wt of 16,000 and a serine protease inhibitor of mol. wt 7000, linked by non-covalent bonds, at an approximate stoichiometry of 1:1:4. the most active form of the complex was isolated by ion exchange chromatography thr ... | 1992 | 1485334 |
| effects of taipan (oxyuranus scutellatus) venom on erythrocyte morphology and blood viscosity in a human victim in vivo and in vitro. | the case of a snake handler with envenoming due to australian taipan (oxyuranus scutellatus) showing marked morphological changes in his red blood cells is presented. the red cells underwent sphero-echinocytic transformation and in subsequent experiments in vitro the effects of taipan venom on red cells were further characterized. taipan venom induced sphero-echinocytic transformation at nanogram/ml concentrations and led to a marked increase in whole blood viscosity. these changes have not been ... | 1991 | 1949148 |
| platelet procoagulant properties studied with snake venom prothrombin activators. | purified snake venom prothrombin activators were used to probe the procoagulant properties of platelet membranes. human platelets were able to stimulate prothrombin activation by the venom activators from oxyuranus scutellatus and notechis scutatus, while the prothrombin activator from echis carinatus was not affected by the presence of platelets. the prothrombin-converting activity of platelets was further studied with the venom activator from oxyuranus scutellatus and with the factor xa-va com ... | 1987 | 3310319 |
| the taipan (oxyuranus scutellatus) and the effect of its bite. | | 1967 | 6067238 |
| the efficacy of antivenom in the treatment of bites by the papuan taipan (oxyuranus scutellatus canni). | a prospective series of 156 patients systemically envenomed following the bite of a papuan taipan (oxyuranus scutellatus canni) were studied. all patients were treated with appropriate antivenom and clinical course and outcome were compared. the proportion of patients requiring intubation was significantly smaller, and the time to resolution of neurotoxicity and discharge from hospital significantly shorter, in patients receiving antivenom no more than 4 h after the bite. no significant differen ... | 1995 | 7660450 |
| rational design, recombinant preparation, and in vitro and in vivo characterization of human prothrombin-derived hirudin antagonists. | a mutant derivative of human prothrombin in which active site aspartate at position 419 is replaced by an asparagine (d419n-prothrombin) has been designed, expressed in recombinant chinese hamster ovary cells, and purified to homogeneity. d419n-prothrombin was converted to the related molecules d419n-meizothrombin and d419n-thrombin by limited proteolysis by echis carinatus and oxyuranus scutellatus venom protease, respectively, and affinity-purified using an immobilized modified c-terminal hiru ... | 1996 | 8798598 |
| differentiation between proteolytic activation and autocatalytic conversion of human prothrombin. activation of recombinant human prothrombin and recombinant d419n-prothrombin by snake venoms from echis carinatus and oxyuranus scutellatus. | recombinant human prothrombin (r-prothrombin) and recombinant mutant prothrombin with active site asp419 substituted by asn (d419n-prothrombin) were expressed in recombinant cho cells, isolated and purified from the fermentation supernatant. the r-prothrombin and d419n-prothrombin were digested by both echis carinatus venom and oxyuranus scutellatus venom. prior to, during and after activation, generation of thrombin activity and the proteolytic degradation of the prothrombin polypeptide chain w ... | 1996 | 8931132 |
| electrocardiographic abnormalities in patients bitten by taipans (oxyuranus scutellatus canni) and other elapid snakes in papua new guinea. | envenoming by a number of species of snake may affect the myocardium or cause electrocardiographic changes; several different mechanisms have been proposed. in a prospective study of snake bite in papua new guinea, electrocardiographic changes were observed in 36 of 69 patients (52%) envenomed by the taipan (oxyuranus scutellatus), 2 of 6 (33%) envenomed by death adders (acanthophis sp.) and one envenomed by the brown snake (pseudonaja textilis). septal t wave inversion and bradycardias, includi ... | 1997 | 9093629 |
| severe envenomation by the taipan (oxyuranus scutellatus) | | 1997 | 9236765 |
| anionic currents of chick sensory neurons are affected by a phospholipase a2 purified from the venom of the taipan snake. | a neurotoxic phospholipase a2 was purified from the venom of the taipan snake oxyuranus scutellatus scutellatus by three consecutive chromatographic steps on ion exchange resins, followed by an affinity column prepared with a phosphatidylcholine derivative attached to sepharose. the phospholipase was shown to be of type a2 (specific activity of 85 units/mg protein), and an apparent molecular weight of 16,000. amino acid analysis shows the presence of approx. 150 residues with the n-terminal amin ... | 1992 | 1373076 |
| clinical toxicology: a tropical australian perspective. | tropical australia has an amazing diversity of venomous fauna, from "the world's most venomous creature," the multi-tentacled (chirodropid) box jellyfish chironex fleckeri, to aggressive spiders whose venom remains to be characterized. all genera of highly venomous australasian elapid snakes are present, except for tiger snakes. most notable is the taipan (oxyuranus scutellatus), with the most efficient "snap-release" biting mechanism of any snake and venom components causing the full constellat ... | 2000 | 10688264 |
| the structure of human thrombin in relation to autolytic degradation. | human thrombin was obtained by activation of human prothrombin with venom of the australian taipan (oxyuranus scutellatus scutellatus). this thrombin was precipitated with ammonium sulphate (75% saturation) and subsequently purified by gel-filtration (sephadex g-75), ion-exchange (cm-sephadex c-50) and affinity (aminobenzamidine-ch-sepharose) chromatography. the final preparation (affinity thrombin) had a specific activity of 2340 iowa units per absorbance unit (a1cm280). thrombin proteins focus ... | 1976 | 952947 |
| characterization of the prothrombin activator from the venom of oxyuranus scutellatus scutellatus (taipan venom). | | 1980 | 6986908 |
| purification and characterization of a prothrombin activator from the venom of the australian brown snake, pseudonaja textilis textilis. | a simple procedure, involving chromatography on concanavalin a-sepharose and gel filtration, has been developed for the purification of a prothrombin activator from the venom of the australian brown snake pseudonaja textilis textilis. the prothrombin activator, which is a major venom component, is a high molecular weight protein (mr greater than or equal to 200,000) which yields a number of subunits when examined by sds-page. it is related antigenically to the venom prothrombin activator of the ... | 1988 | 3075905 |
| inhibition of red cell ca2+-dependent k+ channels by snake venoms. | we have investigated the effects of several snake venoms on the ca2+-dependent k+ channels of human red cells. a heat-resistant component of the venom of the snake notechis scutatus irreversibly inhibited ca2+-dependent k+ transport with a ki value of 0.1-0.2 micrograms/ml. metabolic changes of the cells modified the maximal effect of the venom. binding of the venom required extracellular ca2+ and was quick, but development of full inhibition required additional time. the effects of the venoms f ... | 1989 | 2930782 |
| identification and properties of very high affinity brain membrane-binding sites for a neurotoxic phospholipase from the taipan venom. | four new monochain phospholipases were purified from the oxyuranus scutellatus (taipan) venom. three of them were highly toxic when injected into mice brain. one of these neurotoxic phospholipases, os2, was iodinated and used in binding experiments to demonstrate the presence of two families of specific binding sites in rat brain synaptic membranes. the affinities were exceptionally high, kd1 = 1.5 +/- 0.5 pm and kd2 = 45 +/- 10 pm, and the maximal binding capacities were bmax 1 = 1 +/- 0.4 and ... | 1989 | 2544597 |
| identification and purification of a very high affinity binding protein for toxic phospholipases a2 in skeletal muscle. | oxyuranus scutellatus toxin 1 (os1) and toxin 2 (os2) are two monochain phospholipases a2 isolated from the venom of taipan. their iodinated derivatives have been used to characterize phospholipase a2 receptors on rabbit skeletal muscle cells in culture. both ligands recognize one family of binding sites on myotube membranes with a bmax of 1.9 to 2.2 pmol/mg of protein and dissociation constant values of 7.4 pm for 125i-os2 and 38 pm for 125i-os1. other snake venom phospholipases a2 are able to ... | 1990 | 2160984 |
| an epidemiological study of snake bite envenomation in papua new guinea. | we report a study of 347 patients with snake bite envenomation in papua new guinea. the male: female ratio of the victims was 1.6:1 and their mean age was 24.5 years; 26% were children less than 15 years old. in all cases in which the bite site was known (334) the snake had bitten the extremities of the victim, with 71.3% of these bites being on the ankle or below. the patients came from three regions: urban papua, rural papua and (mostly rural) new guinea. snake bites occurred more frequently d ... | 1991 | 1994203 |
| activation of human factor vii by the prothrombin activator from the venom of oxyuranus scutellatus (taipan snake). | the crude venom of oxyuranus scutellatus (taipan snake) was found to cleave single-chain human factor vii to yield a two-chain molecule indistinguishable from authentic factor viia by sds-polyacrylamide gel electrophoresis. a protease that activates factor vii was purified from this venom by a combination of gel permeation and ion-exchange chromatography. characterization of the venom factor vii activator revealed its apparent identity with the oxyuranus scutellatus prothrombin activator. the pu ... | 1992 | 1604437 |
| secretory phospholipase a2 potentiates glutamate-induced rat striatal neuronal cell death in vivo. | the secretory phospholipases a2 (spla2) os2 (10, 20 and 50 pmol) or os1, (50 pmol) purified from taipan snake oxyuranus scutellatus scutellatus venom, and the excitatory amino acid glutamate (glu) (2.5 and 5.0 micromol) were injected into the right striatum of male wistar rats. injection of 10 and 20 pmol os2 caused no neurological abnormalities or tissue damage. os2 (50 pmol) caused apathy and circling towards the injection side. histology revealed an infarct at the injection site. injection of ... | 1999 | 10548416 |
| the effects of antivenom on the in vitro neurotoxicity of venoms from the taipans oxyuranus scutellatus, oxyuranus microlepidotus and oxyuranus scutellatus canni. | the venoms of the inland (oxyuranus microlepidotus), coastal (o. scutellatus) and papuan (o. s. canni) taipans are among the most potent in the world. the present study compared the in vitro neurotoxic effects of these venoms and the protective effects of taipan antivenom. venom (10 microg/ml) from all three snakes abolished nerve-mediated twitches of the chick biventer cervicis muscle preparation with the following rank order of potency (based on the time taken to inhibit 90% of the twitch resp ... | 1999 | 10519654 |
| a pharmacological examination of venom from the papuan taipan (oxyuranus scutellatus canni). | the papuan taipan (oxyuranus scutellatus canni) is the third most venomous terrestrial snake in the world, however, little is know about the pharmacology of the venom. in the chick biventer cervicis muscle, venom (10 microg/ml) abolished nerve-mediated twitches (time to 90% inhibition (t90) 44+/-5 min, n = 9). this inhibition was unaffected by prior incubation of the venom with the phospholipase a inhibitor 4-bromophenacyl bromide (4-bpb; 0.72 mm) (t90 48+/-7 min, n = 8). the mouse phrenic nerve ... | 1999 | 10519650 |
| identification of a new high-affinity binding protein for neurotoxic phospholipases a2. | ammodytoxin c is a neurotoxic phospholipase a2 which blocks the release of neurotransmitter from the nerve terminal. using a radioiodinated derivative of the toxin, we located its specific high-affinity binding site in the demyelinated p2 fraction of porcine cerebral cortex (kd = 15 nm; bmax = 1.5 pmol/mg membrane protein). in cross-linking experiments on a membrane preparation, 125i-ammodytoxin c labeled a protein of 25 kda. the formation of a specific adduct was not inhibited by nontoxic phosp ... | 1998 | 9790932 |
| cross-neutralisation of australian brown snake, taipan and death adder venoms by monovalent antibodies. | an understanding of the cross-neutralisation of snake venoms by antibodies is important for snake antivenom development. we investigated the cross-neutralisation of brown snake (pseudonaja textilis) venom, taipan (oxyuranus scutellatus) venom and death adder (acanthophis antarcticus) with commercial antivenoms and monovalent anti-snake igg, using enzyme immunoassays, in vitro clotting and neurotoxicity assays. each commercial antivenom bound all three venoms, and neutralised clotting activity of ... | 2010 | 19879227 |
| brown snakes (pseudonaja genus): venom yields, prothrombin activator neutralization and implications affecting antivenom usage. | the recent high prevalence of fatal bites by brown snakes (pseudonaja genus) has led to this study of venom yields from 66 brown snake milkings over 15 months. the amount of venom obtained from all species was higher than reported previously. electrophoretic and western blotting analyses of their venoms showed significantly lower avidity of brown snake antivenom (bs-av) for the prothrombin activator (pa) component (190 kd) than for other venom components, including the neurotoxins. the ld50 of p ... | 1998 | 9619222 |
| a novel small conductance ca2+-activated k+ channel blocker from oxyuranus scutellatus taipan venom. re-evaluation of taicatoxin as a selective ca2+ channel probe. | taicatoxin, isolated from the venom of the australian taipan snake oxyuranus scutellatus, has been previously regarded as a specific blocker of high threshold ca2+ channels in heart. here we show that taicatoxin (in contrast to a range of other ca2+ channel blockers) interacts with apamin-sensitive, small conductance, ca2+-activated potassium channels on both chromaffin cells and in the brain. taicatoxin displays high affinity recognition of 125i-apamin acceptor-binding sites, present on rat syn ... | 1997 | 9242659 |
| endogenous thrombin potential as a novel method for the characterization of procoagulant snake venoms and the efficacy of antivenom. | venom-induced consumption coagulopathy occurs in snake envenoming worldwide but the interaction between procoagulant snake venoms and human coagulation remains poorly understood. we aimed to evaluate an assay using endogenous thrombin potential (etp) to investigate the procoagulant properties of a range of australian whole venoms in human plasma and compared this to traditional clotting and prothrombinase activity studies. we developed a novel modification of etp using procoagulant snake venoms ... | 2010 | 20338189 |
| preclinical evaluation of caprylic acid-fractionated igg antivenom for the treatment of taipan (oxyuranus scutellatus) envenoming in papua new guinea. | snake bite is a common medical emergency in papua new guinea (png). the taipan, oxyuranus scutellatus, inflicts a large number of bites that, in the absence of antivenom therapy, result in high mortality. parenteral administration of antivenoms manufactured in australia is the current treatment of choice for these envenomings. however, the price of these products is high and has increased over the last 25 years; consequently the country can no longer afford all the antivenom it needs. this situa ... | 2011 | 21610854 |
| effects on behaviour and eeg of single chain phospholipases a2 from snake and bee venoms injected into rat brain: search for a functional antagonism. | three phospholipase a2 (pla2s), os1 and os1 purified from the taipan snake venom oxyuranus scutellatus scutellatus and bee venom pla2 were injected to rats by the intracerebroventricular route. os1 showed no sign of neurotoxicity at doses at which os2 and bee venom pla2 produced multiform dose-dependent behavioural effects including motor disturbances (stereotyped movements), compulsive scratching, convulsions and breathing difficulties. eeg recordings showed at the very time when the animal was ... | 1996 | 8737971 |
| snake bites by the papuan taipan (oxyuranus scutellatus canni): paralysis, hemostatic and electrocardiographic abnormalities, and effects of antivenom. | one hundred sixty-six patients with enzyme immunoassay-proven bites by taipans (oxyuranus scutellatus canni) were studied in port moresby, papua new guinea. one hundred thirty-nine (84%) showed clinical evidence of envenoming: local signs were trivial, but most developed hemostatic disorders and neurotoxicity. the blood of 77% of the patients was incoagulable and 35% bled spontaneously, usually from the gums. fifty-one per cent had microscopic hematuria. neurotoxic signs (ptosis, ophthalmoplegia ... | 1995 | 7611559 |
| detection of venom-antivenom (vav) immunocomplexes in vitro as a measure of antivenom efficacy. | the measurement of free venom with enzyme immunoassay in serum of patients with snake envenoming is used to confirm snake identification and to determine if sufficient antivenom has been given. recent studies with russell's viper (rv; daboia russelii) envenoming have detected free venom post-antivenom despite recovery of coagulopathy. this raises the question as to whether this assay also measures venom-antivenom (vav) complexes. in this study we developed an assay to measure vav complexes and i ... | 2014 | 24252422 |
| coagulopathy following bites by the papuan taipan (oxyuranus scutellatus canni). | the mechanisms of haemostatic failure were studied in 87 patients bitten by the papuan taipan (oxyuranus scutellatus canni). eighty (92%) had evidence of a coagulopathy on laboratory testing; 36 (41.4%) developed spontaneous systemic bleeding, although this was rarely of clinical significance. coagulation assays in 48 completely defibrinated patients showed marked reductions in factors v and viii and reductions in factors ii, ix, xi, xii and xiiia. there was a reduction in plasminogen and alpha ... | 1995 | 7540879 |
| ultrastructural effects of the venom of the small-scaled snake (parademansia microlepidotus) on the nerve terminals of the rat diaphragm. | venom of the small-scaled snake (parademansia microlepidotus) causes a large increase in the number of coated omega figures inserted in the axolemma of nerve terminals. it also causes both a loss of synaptic vesicles and an increase in the number of neurofilaments in the nerve terminals. the actions of the venom are very similar to taipoxin, a pre-synaptic neurotoxin from the venom of the taipan (oxyuranus scutellatus). the morphological changes in the nerve terminals caused by the small-scaled ... | 1980 | 7436884 |
| development of a chicken-derived antivenom against the taipan snake (oxyuranus scutellatus) venom and comparison with an equine antivenom. | a chicken-derived antivenom (chdav) towards taipan snake (oxyuranus scutellatus) venom was produced by purifying anti-taipan igy from egg yolks of hens immunized with taipan venom. the productivity, antivenomic profile, neutralization ability, pharmacokinetic properties and immunogenicity of the chdav were compared with those of an antivenom produced in horses (edav). we found that 382 eggs are required to produce the mass of anti-taipan antibodies contained in one liter of equine hyperimmune pl ... | 2016 | 27373994 |
| myotoxic activity of the crude venom and the principal neurotoxin, taipoxin, of the australian taipan, oxyuranus scutellatus. | 1 the crude venom of the australian taipan. oxyuranus scutellatus and its principal neurotoxin, taipoxin, were injected into the anterolateral aspect of one hind limb of the rat. 2 the effects of the venom and toxin on the morphology and physiology on the underlying soleus muscles were examined. 3 both the crude venom and the toxin caused necrosis and degeneration of the muscle. damage to the peripheral muscle fibres could be seen at the light microscopic level as early as 3 h after injection of ... | 1982 | 7082907 |
| in vitro coagulant properties of venoms from australian snakes. | the procoagulant properties of venous australian snakes are limited to prothrombin activation. venoms of notechis scutatus, tropidechis carinatus and pseudechis porphyriacus require phospholipid, calcium and factor v to maximally activate normal prothrombin. venoms of pseudonaja textilis and oxyuranus microlepidotus activate both normal prothrombin and the decarboxy form and do not require co-factors. the actions of the venom of oxyuranus scutellatus are dependent on concentration. | 1982 | 7080056 |
| vintage venoms: proteomic and pharmacological stability of snake venoms stored for up to eight decades. | for over a century, venom samples from wild snakes have been collected and stored around the world. however, the quality of storage conditions for "vintage" venoms has rarely been assessed. the goal of this study was to determine whether such historical venom samples are still biochemically and pharmacologically viable for research purposes, or if new sample efforts are needed. in total, 52 samples spanning 5 genera and 13 species with regional variants of some species (e.g., 14 different popula ... | 2014 | 24434587 |
| the mass of venom injected by two elapidae: the taipan (oxyuranus scutellatus) and the australian tiger snake (notechis scutatus). | using an enzyme immunoassay technique, a new method for measuring, in vivo, the mass of venom injected during snake bite, is presented. the venom injected into mice (as prey) and the venom left on the skin surface during bites by the two australian elapidae, the taipan (oxyuranus scutellatus) and the tiger snake (notechus scutatus) has been measured. venom delivery patterns vary significantly between these two species. in the case of the tiger snake (a total of 45 bites studied) the mean mass of ... | 1982 | 6753241 |
| regeneration of mammalian skeletal muscle following the injection of the snake-venom toxin, taipoxin. | taipoxin, a toxin isolated from the venom of the snake oxyuranus scutellatus was injected subcutaneously into the anterolateral aspect of one hind limb of the rat. the toxin caused a necrotising myopathy in the underlying muscle. the ultrastructural characteristics of the regeneration that followed the administration of the myotoxin were studied. regeneration occurred within the surviving basal lamina tubes from a population of spared satellite cells. myotubes were formed by 3 days and small imm ... | 1983 | 6883457 |
| recombinant snake venom prothrombin activators. | three prothrombin activators; ecarin, which was originally isolated from the venom of the saw-scaled viper echis carinatus, trocarin from the rough-scaled snake tropidechis carinatus, and oscutarin from the taipan snake oxyuranus scutellatus, were expressed in mammalian cells with the purpose to obtain recombinant prothrombin activators that could be used to convert prothrombin to thrombin. we have previously reported that recombinant ecarin can efficiently generate thrombin without the need for ... | 2015 | 23111318 |
| viper venoms and coumarin-induced prothrombin. a comparison of several one-stage methods employing three different venoms as thromboplastins. | three venoms obtained from three vipers, namely echis carinatus, notechis scutatus scutatus and oxyuranus scutellatus, have been used as thromboplastin in a one-stage assay of coumarin-induced prothrombin. regardless of the venom used, prothrombin resulted to be low in coumarin-treated patients. the mean values obtained were 27.2, 33.6, and 24.2%, respectively. these values were comparable to those obtained by means of the classical one-stage method (24.8%). a good correlation was observed among ... | 2004 | 959712 |
| amidolytic assay of factor v in human plasma. | an amidolytic assay was developed for measuring factor v in human plasma. diluted plasma is incubated at 37 degrees c with lipid, ca++, taipan snake venom (oxyuranus scutellatus scutellatus) and bovine prothrombin. the reaction is stopped after 4 min with edta. the content of factor v in samples is then determined by measuring the amidolytic activity of formed thrombin on synthetic chromogenic peptide substrate s-2238, h-d-phe-pip-arg-pna. the assay appears to be specific for factor v as: human ... | 1986 | 3515615 |
| the molecular basis of cross-reactivity in the australian snake venom detection kit (svdk). | the snake venom detection kit (svdk) is of major medical importance in australia, yet it has never been rigorously characterised in terms of its sensitivity and specificity, especially when it comes to reports of false-negative and false-positive results. this study investigates reactions and cross-reactions of five venoms the svdk is directed against and a number of purified toxins. snakes showing the closest evolutionary relationships demonstrated the lowest level of cross-reactivity between g ... | 2007 | 17904179 |
| identification of different receptor types for toxic phospholipases a2 in rabbit skeletal muscle. | oxyuranus scutellatus scutellatus toxins 1 (os1) and 2 (os2) are two phospholipase a2s (pla2) isolated from the venom of the australian taipan snake. their iodinated derivatives have been used to characterize pla2 binding sites on rabbit skeletal muscle. competition and cross-linking experiments indicate that 125i-labelled os2 binding sites in rabbit skeletal muscle in vivo are distributed into two classes of receptors. one class binds os2 and os1 and is insensitive to the bee venom pla2. it is ... | 1991 | 1660004 |
| neutralisation of the clotting activity of australian snake venoms by snake plasma. | plasmas from pseudonaja textilis and notechis scutatus were tested in vitro for their ability to neutralise the procoagulant activity, in human plasma, of nine elapid venoms. pseudonaja textilis plasma inhibited the procoagulant activity of all pseudonaja species and in one taipan (oxyuranus scutellatus). however there was no inhibitory activity against any from the notechis species. plasma from notechis scutatus exhibited no inhibitory activity against any notechis species, including self, only ... | 2000 | 10858522 |
| inhibition of prothrombin activation by bothrojaracin, a c-type lectin from bothrops jararaca venom. | bothrojaracin is a potent and specific alpha-thrombin inhibitor (kd approximately 0.6 nm) isolated from bothrops jararaca venom. it binds to both of thrombin's anion-binding exosites (1 and 2), thus inhibiting the ability of the enzyme to act upon several natural macromolecular substrates, such as fibrinogen, platelet receptor, protein c, and factor v. additionally, bothrojaracin interacts with prothrombin (kd approximately 30 nm), as previously determined by a solid-phase assay. however, there ... | 2000 | 11051105 |
| biochemical and functional characterization of an l-amino acid oxidase isolated from bothrops pirajai snake venom. | in this work we describe the isolation of a new l-amino acid oxidase (laao) referred to as bpirlaao-i from bothrops pirajai snake venom, which was highly purified using a combination of molecular exclusion, affinity, and hydrophobic chromatography steps. bpirlaao-i homodimeric acid glycoprotein (approximate mr and pi of 130,000 and 4.9, respectively) displays high specificity toward hydrophobic/aromatic amino acids, while deglycosylation does not alter its enzymatic activity. the n-terminal laao ... | 2006 | 16809041 |
| digestive properties of the venom of the australian coastal taipan, oxyuranus scutellatus (peters, 1867). | the digestive properties of australian elapid snake venoms have not been studied to any great extent. to address this, the in vitro digestive properties of oxyuranus scutellatus (australian coastal taipan) venom were investigated in a simulation of the in vivo conditions using the parameters reported for the stomach of snakes and representative prey for this species. the amount of soluble protein released was measured over time using a bicinchoninic acid (bca) assay. dismembered mouse hindlegs w ... | 2006 | 16899265 |
| distinct activities of novel neurotoxins from australian venomous snakes for nicotinic acetylcholine receptors. | envenomation from australian elapid snakes results in a myriad of neurological effects due to post-synaptic neurotoxins that bind and inhibit nicotinic acetylcholine receptors (nachrs) of neurons and muscle fibres. however, despite the significant physiological effects of these toxins, they have remained largely undercharacterised at the molecular level. this study describes the identification and comparative analysis of multiple neurotoxin isoforms from ten australian snakes, including function ... | 2007 | 17906946 |
| variations in the pharmacological profile of post-synaptic neurotoxins isolated from the venoms of the papuan (oxyuranus scutellatus canni) and coastal (oxyuranus scutellatus scutellatus) taipans. | based on murine ld(50) values, the taipans (i.e. oxyuranus microlepidotus, oxyuranus scutellatus and oxyuranus scutellatus canni) are the most venomous snake genus in the world. despite this, little is known about the toxins contained in their venoms. the aim of the present study was to isolate and characterise post-synaptic neurotoxins from the venoms of the papuan taipan (o. s. canni) and coastal taipan (o. scutellatus), and to compare their pharmacology. a 6770da toxin (i.e. alpha-oxytoxin 1) ... | 2010 | 20036687 |
| snake venoms as a source of compounds modulating sperm physiology: secreted phospholipases a2 from oxyuranus scutellatus scutellatus impact sperm motility, acrosome reaction and in vitro fertilization in mice. | the goal of this study was to identify new compounds from venoms able to modulate sperm physiology and more particularly sperm motility. for this purpose, we screened the effects of 16 snake venoms cleared of molecules higher than 15 kda on sperm motility. venoms rich in neurotoxins like those from oxyuranus scutellatus scutellatus or daboia russelii, were highly potent inhibitors of sperm motility. in contrast, venoms rich in myotoxins like those from echis carinatus, bothrops alternatus and ma ... | 2010 | 20226834 |
| hypotensive and vascular relaxant effects of phospholipase a2 toxins from papuan taipan (oxyuranus scutellatus) venom. | phospholipase a2 (pla2) toxins are common and abundant components of australasian elapid venoms. these toxins are associated with a range of activities including neurotoxicity, myotoxicity and coagulation disturbances. we have recently reported that sudden cardiovascular collapse induced by papuan taipan (oxyuranus scutellatus) venom involves a combination of the release of dilator autacoids and a direct effect on the smooth muscle. in this study, we aimed to isolate pla2 components from papuan ... | 2014 | 24296315 |
| differential myotoxic and cytotoxic activities of pre-synaptic neurotoxins from papuan taipan (oxyuranus scutellatus) and irian jayan death adder (acanthophis rugosus) venoms. | pre-synaptic pla(2) neurotoxins are important components of many australasian elapid snake venoms. these toxins disrupt neurotransmitter release. taipoxin, a pre-synaptic neurotoxin isolated from the venom of the coastal taipan (oxyuranus scutellatus), causes necrosis and muscle degeneration. the present study examined the myotoxic and cytotoxic activities of venoms from the papuan taipan (o. scutellatus) and irian jayan death adder (acanthophis rugosus), and also tested their pre-synaptic neuro ... | 2013 | 23311944 |
| cytoskeletal rearrangements in human red blood cells induced by snake venoms: light microscopy of shapes and nmr studies of membrane function. | rbcs (red blood cells) circulating through narrow blood capillaries withstand major deformation. the mechanical and chemical stresses commonly exerted on rbcs continue to attract interest for the study of membrane structure and function. snake venoms are lethal biochemical 'cocktails' that often contain haemotoxins, metalloproteinases, myotoxins, neurotoxins, phosphodiesterases, phospholipases and proteases. we have monitored the effects of 4 snake venoms (pseudechis guttatus, oxyuranus scutella ... | 2012 | 21933154 |
| effect of chlorpromazine and quinacrine on the lethality in mice of the venoms and neurotoxins from several snakes. | antivenoms are the currently available agents for the treatment of intoxication by snake venoms. therapeutic approaches using more generally available drugs could improve treatment of envenomation by reducing the cost of the therapeutic agent, eliminating hypersensitivity reactions to antivenoms, and reducing storage costs. i investigated the efficacies of chlorpromazine and quinacrine with respect to reducing the lethality in mice of bungarus caeruleus venom, bungarus multicinctus venom and its ... | 2009 | 2749762 |
| characterisation of a mannose-binding c-type lectin from oxyuranus scutellatus snake venom. | c-type lectins are calcium-dependent sugar binding proteins and are distributed ubiquitously amongst vertebrate organisms. as part of a wider study on australian snake venom components, we have identified and characterised a c-type lectin from the venom of oxyuranus scutellatus (australian coastal taipan) with mannose-binding activity. this protein exhibited a subunit molecular mass of 15 kda and was found to bind mannose and also bind to and agglutinate erythrocytes in a ca(2+)-dependent manner ... | 2011 | 21115100 |
| functional morphology of the palato-maxillary apparatus in "palatine dragging" snakes (serpentes: elapidae: acanthophis, oxyuranus). | elapid snakes have previously been divided into two groups (palatine erectors and palatine draggers) based on the morphology and inferred movements of their palatine bone during prey transport (swallowing). we investigated the morphology and the functioning of the feeding apparatus of several palatine draggers (acanthophis antarcticus, oxyuranus scutellatus, pseudechis australis) and compared them to published records of palatine erectors. we found that the palatine in draggers does not move as ... | 2010 | 19623628 |
| an examination of cardiovascular collapse induced by eastern brown snake (pseudonaja textilis) venom. | the pseudonaja genus (brown snakes) is widely distributed across australia and bites account for significant mortality. venom-induced consumption coagulopathy (vicc) and, less often, early cardiovascular collapse occur following envenoming by these snakes. we have previously examined possible mechanism(s) behind the early cardiovascular collapse following papuan taipan (oxyuranus scutellatus) envenoming. in the present study, we investigate early cardiovascular collapse in anaesthetized rats fol ... | 2013 | 23830990 |
| effect of drugs on the lethality in mice of the venoms and neurotoxins from sundry snakes. | i investigated the efficacy of 10 drugs with respect to reducing the lethality in mice of the following venoms and their respective neurotoxins: bungarus caeruleus venom; bungarus multicinctus venom, alpha-bungarotoxin, beta-bungarotoxin; crotalus durissus terrificus venom, crotoxin: notechis scutatus scutatus venom; oxyuranus scutellatus venom, taipoxin. the drugs diltiazem, nicergoline, primaquine, verapamil and vesamicol protected mice from the lethality of b. caeruleus venom, b. multicinctus ... | 1991 | 1926164 |
| neutralization of the neuromuscular inhibition of venom and taipoxin from the taipan (oxyuranus scutellatus) by f(ab')2 and whole igg antivenoms. | the neuromuscular junction activity of oxyuranus scutellatus venom and its presynaptic neurotoxin, taipoxin, and their neutralization by two antivenoms were examined in mouse phrenic nerve-diaphragm preparations. the action of taipoxin was also studied at 21°c. the efficacy of the antivenoms was also assessed in an in vivo mouse model. both antivenoms were effective in neutralizing the neuromuscular blocking activity in preincubation-type experiments. in experiments involving independent additio ... | 2016 | 26621539 |
| identification and characterisation of kunitz-type plasma kallikrein inhibitors unique to oxyuranus sp. snake venoms. | as part of a wider study on australian snake venom components, we have identified and characterised kunitz-type protease inhibitors from the venoms of oxyuranus scutellatus and oxyuranus microlepidotus (australian taipans) with plasma kallikrein inhibitory activity. each inhibitor had a mass of 7 kda and was purified from the venom as part of a protein complex. mass spectrometry and n-terminal sequencing was employed to obtain amino acid sequence information for each inhibitor and a recombinant ... | 2012 | 21843588 |
| solving the 'brown snake paradox': in vitro characterisation of australasian snake presynaptic neurotoxin activity. | pseudonaja textilis (eastern brown snake) and oxyuranus scutellatus scutellatus (coastal taipan) are clinically important australian elapid snakes, whose potent venoms contain the presynaptic (β) neurotoxins, textilotoxin and taipoxin, respectively, and a number of postsynaptic neurotoxins. however, while taipan envenoming frequently results in neurotoxicity, brown snake envenoming causes an isolated coagulopathy and neurotoxicity is rare. this phenomenon is called the 'brown snake paradox'. thi ... | 2012 | 22343038 |
| failure of 3,4-diaminopyridine and edrophonium to produce significant clinical benefit in neurotoxicity following the bite of papuan taipan (oxyuranus scutellatus canni). | progressive systemic neurotoxicity is a common feature in patients envenomed following the bite of a papuan taipan (oxyuranus scutellatus canni). respiratory paralysis, which commonly results, accounts for considerable morbidity and mortality. established neurotoxicity does not respond to antivenom. in this study, a combination of clinical and electrophysiological variables was used to assess the effect of edrophonium and 3,4-diaminopyridine in patients with significant neurotoxicity. both drugs ... | 2013 | 7570895 |
| electrophysiological findings in patients envenomed following the bite of a papuan taipan (oxyuranus scutellatus canni). | electrophysiological studies were done on patients with systemic neurotoxicity following the bite of a papuan taipan (oxyuranus scutellatus canni). evoked compound muscle action potentials decreased and increased in tandem with clinical deterioration and recovery. nerve conduction velocities did not change in envenomed patients and were consistent with control studies. repetitive nerve stimulation studies showed decremental responses in envenomed patients with post-tetanic potentiation followed ... | 2009 | 7570884 |
| the effects of taipoxin and notexin on the function and fine structure of the murine neuromuscular junction. | the isolated neurotoxins taipoxin and notexin from the venoms of the elapidae, oxyuranus scutellatus and notechis scutatus scutatus respectively cause a neuromuscular block when administered to the mouse in vivo or to the phrenic nerve-hemidiaphragm preparation in vitro. the block is preceded by a latency period during which the toxins bind irreversibly to the nerve. the period is shortened by nerve activity. the frequency of the miniature end-plate potentials is gradually reduced, almost to zer ... | 1976 | 11370228 |
| prothrombin activation by an activator from the venom of oxyuranus scutellatus (taipan snake). | the prothrombin activator from the venom of oxyuranus scutellatus (taipan snake) was purified by gel filtration on sephadex g-200 and ion-exchange chromatography on qae-sephadex. the activator is a large protein with a molecular weight of approximately 300,000, which is composed of subunits of mr 110,000 and 80,000 and two disulfide-linked polypeptides of mr 30,000. one or both of these mr 30,000 subunits contain the active site. the venom activator readily converts factor xa-specific chromogeni ... | 1986 | 3531198 |
| interaction of bothrojaracin with prothrombin. | bothrojaracin (bjc) is a 27-kd protein from bothrops jararaca venom that interacts with alpha-thrombin (k(d) = 0.7 nm) through both anion-binding exosites i and ii. recently, it has been shown that bjc interacts with the exosite i precursor (proexosite i) on human prothrombin (k(d) = 75 nm), forming a 1:1 ca(2+)-independent noncovalent complex with the zymogen. complex formation was associated with inhibition of zymogen activation by oxyuranus scutellatus venom. in addition, bjc strongly decreas ... | 2001 | 11910195 |
| proexosite-1-dependent recognition and activation of prothrombin by taipan venom. | an activator complex from the venom of oxyuranus scutellatus scutellatus (taipan venom) is known to rapidly activate prothrombin to thrombin. to determine whether, similar to prothrombinase, taipan venom utilizes proexosite-1 on prothrombin for a productive complex assembly, the activation of proexosite-1 mutants of prethrombin-1 by the partially purified venom was studied. it was discovered that basic residues of this site (arg(35), lys(36), arg(67), lys(70), arg(73), arg(75), and arg(77)) are ... | 2004 | 14769787 |
| snakes across the strait: trans-torresian phylogeographic relationships in three genera of australasian snakes (serpentes: elapidae: acanthophis, oxyuranus, and pseudechis). | we analyze the phylogeny of three genera of australasian elapid snakes (acanthophis-death adders; oxyuranus-taipans; pseudechis-blacksnakes), using parsimony, maximum likelihood, and bayesian analysis of sequences of the mitochondrial cytochrome b and nd4 genes. in acanthophis and pseudechis, we find evidence of multiple trans-torresian sister-group relationships. analyses of the timing of cladogenic events suggest crossings of the torres strait on several occasions between the late miocene and ... | 2005 | 15579378 |
| molecular evidence for the first records of facultative parthenogenesis in elapid snakes. | parthenogenesis is a form of asexual reproduction by which embryos develop from unfertilized eggs. parthenogenesis occurs in reptiles; however, it is not yet known to occur in the widespread elapid snakes (elapidae), which include well-known taxa such as cobras, mambas, taipans and sea snakes. here, we describe the production of viable parthenogens in two species of australo-papuan elapids with divergent reproductive modes: the oviparous coastal/papuan taipan (oxyuranus scutellatus) and the vivi ... | 2018 | 29515892 |
| novel natriuretic peptides from the venom of the inland taipan (oxyuranus microlepidotus): isolation, chemical and biological characterisation. | three natriuretic-like peptides (tnp-a, tnp-b, and tnp-c) were isolated from the venom of oxyuranus microlepidotus (inland taipan) and were also present in the venoms of oxyuranus scutellatus canni (new guinea taipan) and oxyuranus scutellatus scutellatus (coastal taipan). they were isolated by hplc, characterised by mass spectrometry and edman analysis, and consist of 35-39 amino acid residues. these molecules differ from anp/bnp through replacement of invariant residues within the 17-membered ... | 2005 | 15652496 |
| argatroban-coupled affi-gel matrix for the purification of thrombin from plasma. | sometimes it is necessary to obtain thrombin from limited amounts of human plasma for laboratory assay. none of the available purification methods easily deals with this subject. the procedure described in the present paper uses a readily available pharmaceutical agent, argatroban, to construct an affinity matrix. argatroban has a high affinity for thrombin and its thrombin binding is reversible. prothrombin derived from a ba(2+) precipitate of human plasma is used as the starting material. the ... | 2005 | 15801910 |
| isolation and pharmacological characterization of cannitoxin, a presynaptic neurotoxin from the venom of the papuan taipan (oxyuranus scutellatus canni). | the papuan taipan (oxyuranus scutellatus canni) is widely distributed throughout much of papua new guinea. although neurotoxicity is a major symptom of envenomation, no neurotoxins have been isolated from this venom. using a series of size exclusion chromatography steps, we report the isolation of cannitoxin, a presynaptic neurotoxin (44,848 da) that represents approximately 16% of the whole venom. the toxin displayed high phospholipase a2 (pla2 activity (330 +/- 5 micromol/min/mg) and caused co ... | 2005 | 16135698 |
| label-free (xic) quantification of venom procoagulant and neurotoxin expression in related australian elapid snakes gives insight into venom toxicity evolution. | this study demonstrates a direct role of venom protein expression alteration in the evolution of snake venom toxicity. avian skeletal muscle contractile response to exogenously administered acetylcholine is completely inhibited upon exposure to south australian and largely preserved following exposure to queensland eastern brown snake pseudonaja textilis venom, indicating potent postsynaptic neurotoxicity of the former and lack thereof of the latter venom. label-free quantitative proteomics reve ... | 2015 | 26486890 |
| antivenomic characterization of two antivenoms against the venom of the taipan, oxyuranus scutellatus, from papua new guinea and australia. | antivenoms manufactured by biocsl limited (australia) and instituto clodomiro picado (costa rica) against the venom of the taipan snakes (oxyuranus scutellatus) from australia and papua new guinea (png), respectively, were compared using antivenomics, an analytical approach that combines proteomics with immunoaffinity chromatography. both antivenoms recognized all venom proteins present in venom from png o. scutellatus, although a pattern of partial recognition was observed for some components. ... | 2014 | 25157124 |
| antithrombin-resistant prothrombin yukuhashi mutation also causes thrombomodulin resistance in fibrinogen clotting but not in protein c activation. | prothrombin yukuhashi (p.arg596leu) mutation can result in thrombophilia associated with antithrombin (at) resistance. mutant thrombin, an active form of prothrombin yukuhashi, demonstrated moderately lower clotting activity than the wild-type but substantially impaired the formation of the complex with at. however, the effects of the mutation on the thrombomodulin (tm)-protein c (pc) anticoagulant system have not been previously elucidated. | 2014 | 25149909 |
| development of a new laboratory test to evaluate antithrombin resistance in plasma. | we recently reported a variant prothrombin (p.arg596leu: prothrombin yukuhashi) that confers antithrombin resistance to patients with hereditary thrombosis. to detect antithrombin resistance in plasma, we devised a laboratory test analyzing the kinetics of thrombin inactivation using antithrombin. | 2014 | 24325876 |
| in vivo and in vitro cardiovascular effects of papuan taipan (oxyuranus scutellatus) venom: exploring "sudden collapse". | 'sudden collapse' following envenoming by some australasian elapids is a poorly understood cause of mortality. we have previously shown that oxyuranus scutellatus venom causes cardiovascular collapse in anaesthetized rats. prior administration of a sub lethal dose of venom attenuated the response to subsequent administration of higher (lethal) venom doses. in this study, we investigated the possible mechanisms mediating this 'protective effect'. papuan taipan venom (5μg/kg, i.v.) produced a smal ... | 2012 | 22771951 |
| comparative proteomic analysis of the venom of the taipan snake, oxyuranus scutellatus, from papua new guinea and australia: role of neurotoxic and procoagulant effects in venom toxicity. | the venom proteomes of populations of the highly venomous taipan snake, oxyuranus scutellatus, from australia and papua new guinea (png), were characterized by reverse-phase hplc fractionation, followed by analysis of chromatographic fractions by sds-page, n-terminal sequencing, maldi-tof mass fingerprinting, and collision-induced dissociation tandem mass spectrometry of tryptic peptides. proteins belonging to the following seven protein families were identified in the two venoms: phospholipase ... | 2012 | 22266484 |
| identification and analysis of venom gland-specific genes from the coastal taipan (oxyuranus scutellatus) and related species. | australian terrestrial elapid snakes contain amongst the most potently toxic venoms known. however, despite the well-documented clinical effects of snake bite, little research has focussed on individual venom components at the molecular level. to further characterise the components of australian elapid venoms, a complementary (cdna) microarray was produced from the venom gland of the coastal taipan (oxyuranus scutellatus) and subsequently screened for venom gland-specific transcripts. a number o ... | 2005 | 16261251 |
| full length nucleotide sequence of a factor v-like subunit of oscutarin from oxyuranus scutellatus scutellatus (coastal taipan). | an oxyuranus scutellatus scutellatus venom gland cdna expression library was screened with antivenom. positive clones were isolated and their nucleotide sequences determined. the complete sequence for a factor v-like component from the taipan venom prothrombin activator, oscutarin (ec 3.4.21.60) (walker, f.j., owen, w.g., esmon, c.t., 1980. characterization of the prothrombin activator from the venom of oxyuranus scutellatus scutellatus (taipan venom). biochemistry, 19(5), 1020-1023; speijer, h. ... | 2005 | 15993914 |
| textilinins from pseudonaja textilis textilis. characterization of two plasmin inhibitors that reduce bleeding in an animal model. | the incidence of vein-graft occlusion associated with myocardial infarction and thrombosis following the use of the plasmin inhibitor, aprotinin, to reduce blood loss during vascular surgery has prompted the isolation of an alternative kinetically distinct inhibitor of plasmin from the venom of pseudonaja textilis. this inhibitor has been called textilinin (txln) and two distinct forms have been isolated from the brown-snake venom (molecular weight, 6688 and 6692). a comparison of plasmin inhibi ... | 2000 | 10847427 |
| severe envenomation by the taipan (oxyuranus scutellatus) | we describe cases of five patients with taipan envenomation which indicate that patients with paresis benefit from repeated doses of antivenom, even if given long after the bite, and that fresh frozen plasma should be given to correct coagulopathy that persists after reversal of neuromuscular blockade. we reiterate the importance of compression bandages. | 2004 | 8985453 |
| two novel alpha-neurotoxins isolated from the taipan snake, oxyuranus scutellatus, exhibit reduced affinity for nicotinic acetylcholine receptors in brain and skeletal muscle. | three novel toxic peptides were purified to homogeneity from the venom of the australian taipan snake, oxyuranus scutellatus scutellatus. on the basis of complete amino acid sequence analyses, two of these toxins belong to the family of short-chain alpha-neurotoxins found in elapid and hydrophid snake venoms and are the first postsynaptic neurotoxins identified in taipan venom. radioligand binding studies confirm that taipan toxins 1 and 2 inhibit the binding of [125i]-alpha-bungarotoxin to nico ... | 1996 | 8672493 |
| neurotoxicity and haemostatic disturbances in patients envenomed by the papuan black snake (pseudechis papuanus). | among 335 patients presenting with snakebites in central province, papua new guinea, nine were proved by enzyme immunoassay to have been bitten by papuan black snakes (pseudechis papuanus). seven showed clinical evidence of envenoming. early symptoms included vomiting and tender local lymph nodes. five patients had neurotoxic signs and one required mechanical ventilation. spontaneous systemic bleeding occurred in two patients. coagulation studies in four patients showed thrombocytopenia, prolong ... | 1994 | 7985197 |
| the biological properties of venoms from juvenile and adult taipan (oxyuranus scutellatus) snakes. | 1. the biological properties of four venom pooled samples from adult taipan (oxyuranus scutellatus) snakes and one pooled venom sample from six juvenile taipan snakes (11 months old) were compared. 2. the intravenous ld50 (median lethal dose), procoagulant activity and enzymatic activities of the juvenile venom were not significantly different from those of the adult venoms. 3. the juvenile and adult venoms exhibited similar polyacrylamide gel electrophoretic (page) and sds-page patterns, indica ... | 1992 | 1458834 |
| cross-neutralisation of in vitro neurotoxicity of asian and australian snake neurotoxins and venoms by different antivenoms. | there is limited information on the cross-neutralisation of neurotoxic venoms with antivenoms. cross-neutralisation of the in vitro neurotoxicity of four asian and four australian snake venoms, four post-synaptic neurotoxins (α-bungarotoxin, α-elapitoxin-nk2a, α-elapitoxin-ppr1 and α-scutoxin; 100 nm) and one pre-synaptic neurotoxin (taipoxin; 100 nm) was studied with five antivenoms: thai cobra antivenom (tcav), death adder antivenom (daav), thai neuro polyvalent antivenom (tnpav), indian polyv ... | 2016 | 27763543 |
| taipan viper venom and chromogenic substrate (chromozym th). prothrombin assay. no sensitivity to coumarin-induced prothrombin. | prothrombin (factor ii) was assayed in congenital or acquired prothrombin deficiencies and abnormalities using taipan viper (oxyuranus scutellatus) venom as activating agent and adsorbed normal plasma or a chromogenic compound (chromozym-th) as substrates. prothrombin was found to be low, as expected in every instance, regardless of the substrate used. in coumarin treated patients the levels observed were similar to the prothrombin time percentile values and definitely lower than the immunologic ... | 1981 | 6176507 |
| mass spectrometry data and size exclusion chromatography profiles of australian taipan venom toxins. | the compositions of paradoxin and taipoxin (pdx and tpx, respectively) were investigated using size exclusion chromatography (sec) and nano-electrospray ionization mass spectrometry (nano-esi-ms). the elution profiles from size exclusion chromatography of the venoms fromoxyuranus microlepidotusandoxyuranus scutellatuswere similar. fractions corresponding to the trimeric toxins were treated with guanidinium hydrochloride and the individual subunits were separated by hplc. in this report we presen ... | 2016 | 27747265 |
| in-vitro neutralization of the neurotoxicity of coastal taipan venom by australian polyvalent antivenom: the window of opportunity. | coastal taipan (oxyuranus scutellatus) envenoming causes life-threatening neuromuscular paralysis in humans. we studied the time period during which antivenom remains effective in preventing and arresting in vitro neuromuscular block caused by taipan venom and taipoxin. venom showed predominant pre-synaptic neurotoxicity at 3 µg/ml and post-synaptic neurotoxicity at 10 µg/ml. pre-synaptic neurotoxicity was prevented by addition of australian polyvalent antivenom before the venom and taipoxin and ... | 2020 | 33142783 |
| an agonist of the cxcr4 receptor accelerates the recovery from the peripheral neuroparalysis induced by taipan snake envenomation. | envenomation by snakes is a major neglected human disease. hospitalization and use of animal-derived antivenom are the primary therapeutic supports currently available. there is consensus that additional, not expensive, treatments that can be delivered even long after the snake bite are needed. we recently showed that the drug dubbed nucc-390 shortens the time of recovery from the neuroparalysis caused by traumatic or toxic degeneration of peripheral motor neurons. these syndromes are characteri ... | 2020 | 32898186 |
| oxylepitoxin-1, a reversible neurotoxin from the venom of the inland taipan (oxyuranus microlepidotus). | this study describes the characterization of oxylepitoxin-1 (mw 6789), the first postsynaptic neurotoxin isolated from the venom of the inland taipan (oxyuranus microlepidotus), which is the most venomous snake in the world. oxylepitoxin-1, purified using successive steps of size-exclusion and reverse phase-high performance liquid chromatography, produced concentration-dependent (0.3-1.0 microm) inhibition of nerve-mediated (0.1 hz, 0.2 ms, supramaximal v) twitches of the chick biventer cervicis ... | 2006 | 16879898 |
| optimisation of antithrombin resistance assay as a practical clinical laboratory test: development of prothrombin activator using factors xa/va and automation of assay. | antithrombin resistance (atr) is a novel thrombotic risk in abnormal prothrombins. a manual atr assay using oxyuranus scutellatus (ox) venom as a prothrombin activator was established for detecting antithrombin-resistant prothrombin. however, this assay was limited because of ox snake venom availability and its throughput capacity. here, we have improved the atr assay using bovine factors xa and va (fxa/va) as prothrombin activators and have optimised assay conditions for an automated instrument ... | 2018 | 29436777 |
| coastal taipan (oxyuranus scutellatus) envenomation of a dog. | an 8-year-old mixed-breed dog was envenomed by a juvenile coastal taipan (oxyuranus scutellatus). the dog presented initially with coagulopathy and weakness, then developed neuromuscular paralysis and respiratory failure. progressive myopathy peaked 3 days following admission. taipan antivenom administration, mechanical ventilation therapy and supportive patient care resulted in complete recovery. symptoms of neuropathy began to resolve 3 days following envenomation, with the dog discharged 6 da ... | 2015 | 26503536 |
| development of high-throughput screening assays for profiling snake venom phospholipase a2 activity after chromatographic fractionation. | many organisms, ranging from plants to mammals, contain phospholipase a2 enzymes (pla2s), which catalyze the production of lysophospholipids and fatty acid proinflammatory mediators. pla2s are also common constituents of animal venoms, including bees, scorpions and snakes, and they cause a wide variety of toxic effects including neuro-, myo-, cyto-, and cardio-toxicity, anticoagulation and edema. the aim of this study was to develop a generic method for profiling enzymatically active pla2s in sn ... | 2020 | 32502555 |
| a case of acute hypogonadism following taipan (oxyuranus scutellatus) envenomation. | a previously well man developed acute, marked tender bilateral gynaecomastia two months after confirmed taipan (oxyuranus scutellatus) envenomation. he had had laboratory evidence of thrombotic microangiopathy (tma) including microangiopathic haemolytic anaemia, thrombocytopenia and acute kidney injury. scrotal ultrasound revealed bilateral testicular atrophy, his serum testosterone was repeatedly low, while his luteinising and follicle stimulating hormone were elevated. it is hypothesised that ... | 2020 | 32289354 |
| coagulotoxic effects by brown snake (pseudonaja) and taipan (oxyuranus) venoms, and the efficacy of a new antivenom. | snakebite is a neglected tropical disease that disproportionately affects the poor. antivenom is the only specific and effective treatment for snakebite, but its distribution is severely limited by several factors, including the prohibitive cost of some products. papua new guinea (png) is a snakebite hotspot but the high costs of australian antivenoms (thousands of dollars per treatment) makes it unaffordable in png. a more economical taipan antivenom has recently been developed at the instituto ... | 2019 | 30910521 |