287 research outputs found
A Study to Determine the Awareness of Tidewater Industrial Arts Teachers of the Procedures for Proper Handling of Toxic Substances
This study sought to answer the following questions: 1. What are the toxic substances used most frequently in industrial arts laboratories? 2. How are each of these substances stored and handled? 3. Who most frequently handles these substances? 4. Are both students and instructors adequately informed of the potential hazards relating to the use of these substances? 5. What recommendations should be made to increase teacher awareness of the harmful side effects of toxic substances, both on them and their students
Antivenoms for the treatment of spider envenomation
There are several groups of medically important araneomorph and mygalomorph spiders responsible for serious systemic envenomation. These include spiders from the genus Latrodectus (family Theridiidae), Phoneutria (family Ctenidae) and the subfamily Atracinae (genera Atrax and Hadronyche). The venom of these spiders contains potent neurotoxins that cause excessive neurotransmitter release via vesicle exocytosis or modulation of voltage-gated sodium channels. In addition, spiders of the genus Loxosceles (family Loxoscelidae) are responsible for significant local reactions resulting in necrotic cutaneous lesions. This results from sphingomyelinase D activity and possibly other compounds. A number of antivenoms are currently available to treat envenomation resulting from the bite of these spiders. Particularly efficacious antivenoms are available for Latrodectus and Atrax/Hadronyche species, with extensive cross-reactivity within each genera. In the case of Latrodectus antivenoms this is of considerable importance in countries where antivenom is unavailable or where certain antivenoms are associated with an unacceptably high risk of adverse reactions. Moreover, Latrodectus and Atrax antivenoms appear to be effective in the treatment of envenomation by closely related Steatoda spiders (family Theridiidae) or the unrelated spider Missulena bradleyi (family Actinopodidae), respectively. The effectiveness of Loxosceles antivenom in the treatment of the necrotic arachnidism resulting from the bite of recluse spiders is less clear mainly due to late presentation of victims. Antivenom is also available for Phoneutria envenomation but is reserved only for severe cases
Arachnid toxinology in Australia: From clinical toxicology to potential applications
The unique geographic isolation of Australia has resulted in the evolution of a distinctive range of Australian arachnid fauna. Through the pioneering work of a number of Australian arachnologists, toxinologists, and clinicians, the taxonomy and distribution of new species, the effective clinical treatment of envenomation, and the isolation and characterisation of the many distinctive neurotoxins, has been achieved. In particular, work has focussed on several Australian arachnids, including red-back and funnel-web spiders, paralysis ticks, and buthid scorpions that contain neurotoxins capable of causing death or serious systemic envenomation. In the case of spiders, species-specific antivenoms have been developed to treat envenomed patients that show considerable cross-reactivity. Both in vitro and clinical case studies have shown they are particularly efficacious in the treatment of envenomation by spiders even from unrelated families. Despite their notorious reputation, the high selectivity and potency of a unique range of toxins from the venom of Australian arachnids will make them invaluable molecular tools for studies of neurotransmitter release and vesicle exocytosis as well as ion channel structure and function. The venoms of funnel-web spiders, and more recently Australian scorpions, have also provided a previously untapped rich source of insect-selective neurotoxins for the future development of biopesticides and the characterisation of previously unvalidated insecticide targets. This review provides a historical viewpoint of the work of many toxinologists to isolate and characterise just some of the toxins produced by such a unique group of arachnids and examines the potential applications of these novel peptides. Ā© 2006 Elsevier Ltd. All rights reserved
Ī±-Elapitoxin-Aa2a, a long-chain snake Ī±-neurotoxin with potent actions on muscle (Ī±1)<inf>2</inf>Ī²Ī³Ī“ nicotinic receptors, lacks the classical high affinity for neuronal Ī±7 nicotinic receptors
In contrast to all classical long-chain Ī±-neurotoxins possessing the critical fifth disulfide bond, Ī±-elapitoxin-Aa2a (Ī±-EPTX-Aa2a), a novel long-chain Ī±-neurotoxin from the common death adder Acanthophis antarcticus, lacks affinity for neuronal Ī±7-type nicotinic acetylcholine receptors (nAChRs) Ī±-EPTX-Aa2a (8850 Da; 0.1-1 Ī¼M) caused a concentration-dependent inhibition of indirect twitches, and blocked contractures to cholinergic agonists in the isolated chick biventer cervicis nerve-muscle preparation, consistent with a postsynaptic curaremimetic mode of action. Ī±-EPTX-Aa2a (1-10 nM) produced a potent pseudo-irreversible antagonism of chick muscle nAChRs, with an estimated pA2 value of 8.311 Ā± 0.031, which was not reversed by monovalent death adder antivenom. This is only 2.5-fold less potent than the prototypical long-chain Ī±-neurotoxin, Ī±-bungarotoxin. In contrast, Ī±-EPTX-Aa2a produced complete, but weak, inhibition of 125I-Ī±-bungarotoxin binding to rat hippocampal Ī±7 nAChRs (pKI = 3.670), despite high sequence homology and similar mass to a wide range of long-chain Ī±-neurotoxins. The mostly likely cause for the loss of Ī±7 binding affinity is a leucine substitution, in loop II of Ī±-EPTX-Aa2a, for the highly conserved Arg33 in long-chain Ī±-neurotoxins. Arg 33 has been shown to be critical for both neuronal and muscle activity. Despite this substitution, Ī±-EPTX-Aa2a retains high affinity for muscle (Ī±1)2Ī²Ī³Ī“ nAChRs. This is probably as a result of an Arg29 residue, previously shown to be critical for muscle (Ī±1)2Ī²Ī³Ī“ nAChR affinity, and highly conserved across all short-chain, but not long-chain, Ī±-neurotoxins. Ī±-EPTX-Aa2a therefore represents a novel atypical long-chain Ī±-neurotoxin that includes a fifth disulfide but exhibits differential affinity for nAChR subtypes. Copyright Ā© 2010 Published by Elsevier Inc. All rights reserved
Deliberate Self-Poisoning Presenting to an Emergency Medicine Network in South-East Melbourne: A Descriptive Study
Background. Deliberate self-poisoning (DSP) comprises a small but significant proportion of presentations to the emergency department (ED). However, the prevalence and patient characteristics of self-poisoning attendances to EDs in Victoria have not been recently characterised. Aim. To identify and compare the characteristics of adult patients presenting to the three EDs of Monash Health following DSP. Methods. Retrospective clinical audit of adult DSP attendances between 1st July 2009 and 30th June 2012. Results. A total of 3558 cases over three years were identified fulfilling the search criteria. The mean age of patients was 36.3 years with the largest numbers aged between 18 and 30 (38%). About 30% of patients were born overseas. Forty-eight percent were discharged home, 15% were admitted to ED short stay units, and 5% required ICU admission. The median ED length of stay was 359 minutes (IQR 231-607). The most frequently reported substances in DSP were benzodiazepines (36.6%), paracetamol (22.2%), and antipsychotics (12.1%). Exposure to more than one substance for the episode of DSP was common (47%). Conclusion. This information may help identify the trends in poisoning substances used for DSP in Victoria, which in turn may provide clinicians with information to provide more focused and targeted interventions
Intranasal Ketamine for Acute Pain
Objectives: The aim was to review current evidence regarding the off-label use of intranasal ketamine for acute pain presenting in the setting of the emergency department, and secondary to pediatric limb injuries, renal colic, digital nerve block, and migraines.
Results: In all 5 indications reviewed, ketamine demonstrated efficacy in reducing pain. However, when compared with other agents, ketamine did not demonstrate superiority over opioids in pediatric limb injuries or renal colic and was not as efficacious as standard therapy for migraine relief. Ketamine was also associated with a greater incidence of transient adverse reactions, such as dizziness, bitter aftertaste, fatigue, and vomiting than opioid therapies.
Discussion: The current body of evidence is insufficient to support the use of intranasal ketamine over other standard therapies for acute pain. However, current evidence can be used when developing dosing strategies, preparing for adverse reactions, and generating hypotheses for future, more robust research
Interventions for escalation of therapy for acute exacerbations of asthma in children: an overview of Cochrane Reviews
This is a protocol for a Cochrane Review (Overview). The objectives are as follows:
Main objectives
ā¢To summarise Cochrane Reviews on the efficacy and safety of interventions for escalation of treatment for children with acute exacerbations of asthma
Secondary objectives
ā¢To identify gaps in the current evidence base that will inform recommendations for future research and subsequent Cochrane Reviews
ā¢To categorise information on reported outcome measures used in trials of escalation of treatment for acute exacerbations of asthma in children, and to make recommendations for development and reporting of standard outcomes in future trials and reviews
ā¢To identify relevant research papers that have been published since the date of publication of each included revie
Acute paediatric asthma treatment in the prehospital setting: a retrospective observational study
Objectives To describe the incidence of and patterns of āescalated careā (care in addition to standard treatment with systemic corticosteroids and inhaled bronchodilators) for children receiving prehospital treatment for asthma.
Design Retrospective observational study.
Setting State-wide ambulance service data (Ambulance Victoria in Victoria, Australia, population 6.5āmillion)
Participants Children aged 1ā17 years and given a final diagnosis of asthma by the treating paramedics and/or treated with inhaled bronchodilators from 1 July 2019 to 30 June 2020.
Primary and secondary outcome measures We classified āescalation of careā as parenteral administration of epinephrine, or provision of respiratory support. We compared clinical, demographic and treatments administered between those receiving and not receiving escalation of care.
Results Paramedics attended 1572 children with acute exacerbations of asthma during the 1āyear study period. Of these, 22 (1.4%) had escalated care, all receiving parenteral epinephrine. Patients with escalated care were more likely to be older, had previously required hospital admission for asthma and had severe respiratory distress at initial assessment.
Of 1307 children with respiratory status data available, at arrival to hospital, the respiratory status of children had improved overall (normal/mild respiratory distress at initial assessment 847 (64.8%), normal/mild respiratory distress at hospital arrival 1142 (87.4%), p<0.0001).
Conclusions Most children with acute exacerbations of asthma did not receive escalated therapy during their pre-hospital treatment from ambulance paramedics. Most patients were treated with inhaled bronchodilators only and clinically improved by the time they arrived in hospital
Characteristics of frequent emergency department presenters to an Australian emergency medicine network
<p>Abstract</p> <p>Background</p> <p>To describe the characteristics of emergency department (ED) patients defined as frequent presenters (FP) presenting to an Australian emergency department network and compare these with a cohort of non-frequent presenters (NFP).</p> <p>Method</p> <p>A retrospective chart review utilising an electronic emergency medicine patient medical record database was performed on patients presenting to Southern Health EDs from March 2009 to March 2010. Non-frequent presenters were defined as patients presenting less than 5 times and frequent presenters as presenting 8 or more times in the study period. Characteristics of both groups were described and compared.</p> <p>Results</p> <p>During the 12-month study period there were 540 FP patients with 4549 admissions and 73,089 NFP patients with 100,943 admissions. FP patients were slightly older with a significant increase in frequency of patients between the ages of 70 to 79 years and they were more likely to be divorced or separated than NFP patients. Frequent presenters to the emergency department were more likely to utilise the ambulance service to arrive at the hospital, or in the custody of police than NFP patients. FPs were more likely to be admitted to hospital, more likely to have an admission to a mental health bed than NFP patients and more likely to self-discharge from the emergency department while waiting for care.</p> <p>Conclusions</p> <p>There are major implications for the utilisation of limited ED resources by frequent presenters. By further understanding the characteristics of FP we may be able to address the specific health care needs of this population in more efficient and cost effective ways. Further research analysing the effectiveness of targeted multidisciplinary interventions aiming to reduce the frequency of ED attendances may be warranted.</p
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