https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 Australian Sea Snake Envenoming Causes Myotoxicity and Non-Specific Systemic Symptoms - Australian Snakebite Project (ASP-24) https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:53624 2 years. Information about demographics, bite circumstances, species involved, clinical and laboratory features of envenoming, and treatment is collected and entered into a purpose-built database. Results: Between January 2002 and August 2020, 13 patients with suspected sea snake bite were recruited to ASP, 11 were male; median age was 30 years. Bites occurred in Queensland and Western Australia. All patients were in or around, coastal waters at the time of bite. The species involved was identified in two cases (both Hydrophis zweifeli). Local effects occurred in 9 patients: pain (5), swelling (5), bleeding (2), bruising (1). Envenoming occurred in eight patients and was characterised by non-specific systemic features (6) and myotoxicity (2). Myotoxicity was severe (peak CK 28200 and 48100 U/L) and rapid in onset (time to peak CK 13.5 and 15.1 h) in these two patients. Non-specific systemic features included nausea (6), headache (6), abdominal pain (3), and diaphoresis (2). Leukocytosis, neutrophilia, and lymphopenia occurred in both patients with myotoxicity and was evident on the first blood test. No patients developed neurotoxicity or coagulopathy. Early Seqirus antivenom therapy was associated with a lower peak creatine kinase. Conclusion: While relatively rare, sea snake envenoming is associated with significant morbidity and risk of mortality. Early antivenom appears to have a role in preventing severe myotoxicity and should be a goal of therapy.]]> Tue 12 Dec 2023 15:26:45 AEDT ]]> A definite bite by the ornamental snake (Denisonia maculata) causing mild envenoming https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:28154 Denisonia maculata) using enzyme immunoassays. Case: A 9-year old boy was bitten by an identified Ornamental Snake. He developed nausea, vomiting, local pain, and swelling. He had a leucocytosis (white cell count, 20.8 x 10⁹/L), an elevated international normalised ratio (INR) of 1.6, but otherwise normal blood tests including D-Dimer and activated partial thromboplastin time. He was treated with Australian Black Snake antivenom because the commercial venom detection kit was positive for Black snake. He was admitted for 36 h with continuing local pain and swelling requiring parenteral analgesia. Materials and methods: Blood samples were collected with informed consent for measurement of venom and antivenom concentrations. Venom-specific enzyme immunoassays were developed using the closely related D. devisi venom with Rabbit anti-Notechis (Tiger Snake) and anti-Tropidechis (Rough-scaled Snake) IgG antibodies to detect venom in serum. Standard curves for measured venom versus actual venom concentrations were made to interpolate Denisonia venom concentrations. In vitro procoagulant and anticoagulant activity of venom was assayed. Results: Denisonia venom was detected in the pre-antivenom sample as 9.6 ng/mL D. devisi venom. No antigenic venom components were detected in post-antivenom samples and there were high antivenom concentrations. D. devisi venom had mild in vitro procoagulant activity with a minimum concentration required to clot after 5 min of 2.5-5 μg/mL and even weaker anticoagulant activity. Conclusions: Denisonia bites appear to cause local effects and possibly mild systemic envenoming (with only non-specific systemic symptoms and leucocytosis), confirmed by detection of antigenic venom components in blood. A significant coagulopathy does not appear to occur.]]> Sat 24 Mar 2018 07:36:34 AEDT ]]> A current perspective on snake venom composition and constituent protein families https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:50379 Mon 24 Jul 2023 13:02:25 AEST ]]> Activity of two key toxin groups in Australian elapid venoms show a strong correlation to phylogeny but not to diet https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:44536 2 (PLA2), and L-amino acid oxidase (LAAO) – in the venom of 39 species of Australian elapids (40% of terrestrial species diversity) and used linear parsimony and BayesTraits to investigate any correlation between enzyme activity and phylogeny or diet. Results: PLA2 activity ranged from 0 to 481 nmol/min/mg of venom, and LAAO activity ranged from 0 to 351 nmol/min/mg. Phylogenetic comparative methods, implemented in BayesTraits showed that enzyme activity was strongly correlated with phylogeny, more so for LAAO activity. For example, LAAO activity was absent in both the Vermicella and Pseudonaja/Oxyuranus clade, supporting previously proposed relationships among these disparate taxa. There was no association between broad dietary categories and either enzyme activity. There was strong evidence for faster initial rates of change over evolutionary time for LAAO (delta parameter mean 0.2), but no such pattern in PLA2 (delta parameter mean 0.64). There were some exceptions to the phylogenetic patterns of enzyme activity: different PLA2 activity in the ecologically similar sister-species Denisonia devisi and D. maculata; large interspecific differences in PLA2 activity in Hoplocephalus and Austrelaps. Conclusions: We have shown that phylogeny is a stronger influence on venom enzyme activity than diet for two of the four major enzyme families present in snake venoms. PLA2 and LAAO activities had contrasting evolutionary dynamics with the higher delta value for PLA2 Some species/individuals lacked activity in one protein family suggesting that the loss of single protein family may not incur a significant fitness cost.]]> Mon 17 Oct 2022 09:03:36 AEDT ]]> The Eastern Bandy Bandy Vermicella annulata, expresses high abundance of SVMP, CRiSP and Kunitz protein families in its venom proteome. https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:54722 Mon 11 Mar 2024 11:58:32 AEDT ]]> In-vitro neutralization of the neurotoxicity of Coastal Taipan venom by Australian polyvalent antivenom: the window of opportunity https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:40416 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, reversed when antivenom was added 5 min after venom and taipoxin. Antivenom only partially reversed the neurotoxicity when added 15 min after venom and had no significant effect when added 30 min after venom. In contrast, post-synaptic activity was fully reversed when antivenom was added 30 min after venom. The effect of antivenom on pre-synaptic neuromuscular block was reproduced by washing the bath at similar time intervals for 3 µg/mL, but not for 10 µg/mL. We found an approximate 10–15 min time window in which antivenom can prevent pre-synaptic neuromuscular block. This time window is likely to be longer in envenomed patients due to the delay in venom absorption. Similar effectiveness of antivenom and washing with 3 µg/mL venom suggests that antivenom most likely acts by neutralizing pre-synaptic toxins before they interfere with neurotransmission inside the motor nerve terminals.]]> Mon 11 Jul 2022 14:44:40 AEST ]]> Intra-specific venom variation in the Australian coastal taipan Oxyuranus scutellatus https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:40389 Oxyuranus scutellatus from four localities on the north-east coast of Australia, spanning a distance of 2000 km. The intra-specific variation in taipan venom was considerably less than the inter-specific variation between it and the other Australian elapids to which it was compared. The electrophoretic venom profile of O. scutellatus was visually different to six other genera of Australian elapids, but not to its congener inland taipan O. microlepidotus. There was minimal geographical variation in taipan venom, as the intra-population variation exceeded the inter-population variation for enzymatic activity, procoagulant activity, and the abundance of neurotoxins. The pre-synaptic neurotoxin (taipoxin) was more abundant than the post-synaptic neurotoxins (3FTx), with a median of 11.0% (interquartile range (IQR): 9.7% to 18.3%; range: 6.7% to 23.6%) vs. a median of 3.4% (IQR: 0.4% to 6.7%; range: 0% to 8.1%). Three taipan individuals almost completely lacked post-synaptic neurotoxins, which was not associated with geography and occurred within two populations. We found no evidence of sexual dimorphism in taipan venom. Our study provides a basis for evaluating the significance of intra-specific venom variation within a phylogenetic context by comparing it to the inter-specific and inter-generic variation. The considerable intra-population variation we observed supports the use of several unpooled individuals from each population when making inter-specific comparisons.]]> Mon 11 Jul 2022 11:21:41 AEST ]]> The Unusual Metalloprotease-Rich Venom Proteome of the Australian Elapid Snake Hoplocephalus stephensii https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:51420 Mon 04 Sep 2023 14:58:04 AEST ]]> Investigating Toxin Diversity and Abundance in Snake Venom Proteomes https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:48007 Mon 01 May 2023 15:17:16 AEST ]]> A review and database of snake venom proteomes https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:30276 Fri 24 Aug 2018 09:02:03 AEST ]]>