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1.
Clin Exp Allergy ; 47(11): 1478-1490, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28756642

ABSTRACT

BACKGROUND: Allergen immunotherapy uses pharmaceutical preparations derived from naturally occurring source materials, which contain water-soluble allergenic components responsible for allergic reactions. The success of in vivo and in vitro diagnoses in allergen sensitization and allergen immunotherapy largely depends on the quality, composition and uniformity of allergenic materials used to produce the active ingredients, and the formulation employed to prepare finished products. OBJECTIVES: We aimed to examine the factors influencing batch-to-batch consistency of Jack Jumper (Myrmecia pilosula) ant venom (JJAV) in the form of active pharmaceutical ingredient (AI) and informed whether factors such as temperature, artificial light and container materials influence the quality of JJAV AIs. We also aimed to establish handling and storage requirements of JJAV AIs to ensure preservation of allergenic activities during usage in the diagnosis of allergen sensitization and in allergen immunotherapy. METHODS: The quality and consistency of JJAV AIs were analysed using a combination of bicinchoninic acid assay for total protein quantification, HPLC-UV for JJAV allergen peptides quantification, ELISA inhibition for total allergenic potency, SDS-PAGE, AU-PAGE and immunoblot for qualitative assessment of JJAV components, and Limulus Amebocyte Lysate assay for the quantification of endotoxin concentration. API-ZYM and Zymogram assays were used to probe the presence of enzymatic activities in JJAV. RESULTS: Pharmaceutical-grade JJAV for allergen immunotherapy has good batch-to-batch consistency. Temporary storage at 4°C and light exposure do not affect the quality of JJAV. Exposure to temperature above 40°C degrades high MW allergens in JJAV. Vials containing JJAV must be stored frozen and in upright position during long-term storage. CONCLUSIONS AND CLINICAL RELEVANCE: We have identified factors, which can influence the quality and consistency of JJAV AIs, and provided a framework for appropriate handling, transporting and storage of JJAV to be used for the diagnosis of allergen sensitization and in AIT.


Subject(s)
Allergens/immunology , Ant Venoms/immunology , Desensitization, Immunologic , Hypersensitivity/diagnosis , Hypersensitivity/immunology , Hypersensitivity/therapy , Allergens/administration & dosage , Allergens/chemistry , Animals , Ant Venoms/administration & dosage , Ant Venoms/chemistry , Desensitization, Immunologic/methods , Enzyme Activation , Enzyme-Linked Immunosorbent Assay/methods , Enzyme-Linked Immunosorbent Assay/standards , Humans , Immunization , Light , Preservation, Biological , Reproducibility of Results , Temperature
2.
Clin Exp Allergy ; 47(3): 361-370, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27906487

ABSTRACT

BACKGROUND: The mechanisms involved in the amplification of the mast cell response during anaphylaxis are unclear. Mouse models of anaphylaxis demonstrate the critical involvement of neutrophils. These innate immune cells are highly abundant in peripheral blood and can be rapidly activated to trigger both local and systemic inflammation. OBJECTIVE: To investigate neutrophil activation in peripheral blood during acute human anaphylaxis. METHODS: Patients presenting to the emergency department with anaphylaxis underwent blood sampling upon enrolment and at up to three subsequent time-points. Traditional anaphylaxis biomarkers, histamine and mast cell tryptase, were measured by ELISA and ImmunoCAP, respectively. Plasma myeloperoxidase concentrations were measured by ELISA, serum soluble CD62L concentrations by cytometric bead array, and both compared to healthy controls. RESULTS: In 72 patients, 37 (51%) had severe anaphylaxis, 33 (60%) were histamine positive, and 47 (70%) were mast cell tryptase positive. At enrolment, myeloperoxidase concentrations were 2.9- (95% CI: 1.3, 6.5) and 5.0- (95% CI: 2.4, 10.5) fold higher in moderate and severe patients, respectively, compared with healthy controls, and remained stable over the first 5 h following symptom onset. At enrolment, soluble CD62L was 29% (95% CI: 19, 38) and 31% (95% CI: 22, 40) lower in moderate and severe patients, respectively, than healthy controls, and was stable over the first 5 h. There were no associations between myeloperoxidase or soluble CD62L concentrations and either histamine or mast cell tryptase concentrations. CONCLUSIONS AND CLINICAL RELEVANCE: These results provide compelling evidence for the involvement of neutrophils during acute human anaphylaxis, suggesting they are activated early in the reaction, regardless of mast cell activation. This important finding increases our understanding of the basic mechanisms of anaphylaxis, a necessary precursor to improving treatment and prevention.


Subject(s)
Anaphylaxis/immunology , Anaphylaxis/metabolism , Neutrophil Activation/immunology , Neutrophils/immunology , Neutrophils/metabolism , Adult , Allergens/immunology , Anaphylaxis/diagnosis , Anaphylaxis/genetics , Biomarkers , Female , Histamine Release , Humans , L-Selectin/blood , Male , Mast Cells/immunology , Mast Cells/metabolism , Middle Aged , Neutrophil Activation/genetics , Peroxidase/genetics , Peroxidase/metabolism , Tryptases/blood , Young Adult
3.
4.
Intern Med J ; 44(5): 450-7, 2014 May.
Article in English | MEDLINE | ID: mdl-24612237

ABSTRACT

BACKGROUND: Spontaneous pneumothorax can be managed initially by observation, aspiration or chest drain insertion. AIMS: To determine the clinical features of spontaneous pneumothorax in patients presenting to the emergency department (ED), interventions, outcomes and potential risk factors for poor outcomes after treatment. METHODS: Retrospective chart review from ED of three major referral and two general hospitals in Australia of presentations with primary spontaneous pneumothorax (PSP) or secondary spontaneous pneumothorax (SSP). Main outcomes were prolonged air leak (>5 days) and pneumothorax recurrence within 1 year. RESULTS: We identified 225 people with PSP and 98 with SSP. There were no clinical tension pneumothoraces with hypotension. Hypoxaemia (haemoglobin oxygen saturation measured by pulse oximetry ≤92%) occurred only in SSP and in older patients (age >50 years) with PSP. Drainage was performed in 150 (67%) PSP and 82 (84%) SSP. Prolonged air leak occurred in 16% (95% confidence interval 10-23%) of PSP and 31% (21-42%) of SSP. Independent risk factors for prolonged drainage were non-asthma SSP and pneumothorax size >50%. Complications were recorded in 11% (7.5-16%) of those having drains inserted. Recurrences occurred in 5/91 (5%, 1.8-12%) of those treated without drainage versus 40/232 (17%, 13-23%) of those treated by drainage, of which half occurred in the first month after drainage. CONCLUSION: Pneumothorax drainage is associated with substantial morbidity including prolonged air leak. As PSP appears to be well tolerated in younger people even with large pneumothoraces, conservative treatment in this subgroup may be a viable option to improve patient outcomes, but this needs to be confirmed in a clinical trial.


Subject(s)
Drainage/methods , Pneumothorax/surgery , Adult , Aged , Chest Tubes/adverse effects , Chest Tubes/statistics & numerical data , Comorbidity , Drainage/adverse effects , Drainage/instrumentation , Drainage/statistics & numerical data , Emergency Service, Hospital , Female , Hemothorax/epidemiology , Hospitals, General , Humans , Hypoxia/etiology , Length of Stay/statistics & numerical data , Lung Diseases/complications , Male , Middle Aged , Pain/etiology , Patient Transfer , Pneumothorax/complications , Pneumothorax/epidemiology , Pulmonary Atelectasis/etiology , Recurrence , Retrospective Studies , Risk Factors , Rupture, Spontaneous , Treatment Outcome , Wound Infection/etiology , Young Adult
5.
Anaesth Intensive Care ; 41(4): 482-9, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23808507

ABSTRACT

Understanding longer term outcomes in critically ill patients will assist treatment decisions, allocation of scarce resources and clinical research in that population. The aim of this study was to compare a well-validated means of determining comorbidity, the Charlson Comorbidity Score, to other verified risk stratification models in predicting one-year mortality and other outcomes in emergency department patients with severe sepsis and sepsis with shock. We conducted a planned subgroup analysis of a prospective observational study, the Critical Illness and Shock Study, in adult patients with sepsis meeting study criteria for critical illness. From emergency department arrival, patients were prospectively enrolled with data collected for a minimum of one year post-enrolment. Scoring systems were derived from this data and compared using receiver-operating characteristic curves. One hundred and four patients were enrolled. The 28-day mortality was 18% and one-year mortality 40%. For predicting one-year mortality, the area under the receiver-operating characteristic curve for age-weighted Charlson Comorbidity Score (0.71, 95% confidence interval 0.61 to 0.81) was at least as good or superior to other scoring systems analysed. The intensive care unit admission rate was 45% and the median hospital length-of-stay was eight days. We conclude that in patients who present to the emergency department with severe sepsis or sepsis with shock, age-weighted Charlson Comorbidity Score is a predictor of one-year mortality that is simple to calculate and at least as accurate as other validated scoring systems.


Subject(s)
Comorbidity , Sepsis/complications , Sepsis/mortality , Shock, Septic/complications , Shock, Septic/mortality , Aged , Area Under Curve , Cost of Illness , Critical Illness , Cross-Sectional Studies , Data Interpretation, Statistical , Endpoint Determination , Female , Forecasting , Humans , Male , Middle Aged , Patient Selection , Prognosis , ROC Curve , Risk Assessment , Treatment Outcome
6.
Clin Toxicol (Phila) ; 51(5): 417-24, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23586640

ABSTRACT

CONTEXT: Mulga snakes (Pseudechis australis) are venomous snakes with a wide distribution in Australia. Objective. The objective of this study was to describe mulga snake envenoming and the response of envenoming to antivenom therapy. MATERIALS AND METHODS: Definite mulga bites, based on expert identification or venom-specific enzyme immunoassay, were recruited from the Australian Snakebite Project. Demographics, information about the bite, clinical effects, laboratory investigations and antivenom treatment are recorded for all patients. Blood samples are collected to measure the serum venom concentrations pre- and post-antivenom therapy using enzyme immunoassay. RESULTS: There were 17 patients with definite mulga snake bites. The median age was 37 years (6-70 years); 16 were male and six were snake handlers. Thirteen patients had systemic envenoming with non-specific systemic symptoms (11), anticoagulant coagulopathy (10), myotoxicity (7) and haemolysis (6). Antivenom was given to ten patients; the median dose was one vial (range, one-three vials). Three patients had systemic hypersensitivity reactions post-antivenom. Antivenom reversed the coagulopathy in all cases. Antivenom appeared to prevent myotoxicity in three patients with high venom concentrations, given antivenom within 2 h of the bite. Median peak venom concentration in 12 envenomed patients with samples was 29 ng/mL (range, 0.6-624 ng/mL). There was a good correlation between venom concentrations and the area under the curve of the creatine kinase for patients receiving antivenom after 2 h. Higher venom concentrations were also associated with coagulopathy and haemolysis. Venom was not detected after antivenom administration except in one patient who had a venom concentration of 8.3 ng/ml after one vial of antivenom, but immediate reversal of the coagulopathy. DISCUSSION: Mulga snake envenoming is characterised by myotoxicity, anticoagulant coagulopathy and haemolysis, and has a spectrum of toxicity that is venom dose dependant. This study supports a dose of one vial of antivenom, given as soon as a systemic envenoming is identified, rather than waiting for the development of myotoxicity.


Subject(s)
Antivenins/therapeutic use , Blood Coagulation Disorders/chemically induced , Elapid Venoms/poisoning , Muscle, Skeletal/drug effects , Muscular Diseases/chemically induced , Neurotoxins/poisoning , Snake Bites/pathology , Adolescent , Adult , Aged , Australia/epidemiology , Blood Coagulation Disorders/pathology , Child , Female , Humans , Male , Middle Aged , Muscle, Skeletal/pathology , Muscular Diseases/pathology , Prospective Studies , Snake Bites/drug therapy , Snake Bites/epidemiology , Treatment Outcome , Young Adult
7.
J Thromb Haemost ; 11(7): 1310-8, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23565941

ABSTRACT

BACKGROUND: Venom-induced consumption coagulopathy (VICC) is a major effect of snake envenoming. OBJECTIVES: To investigate whether fresh frozen plasma (FFP) given after antivenom resulted in more rapid correction of coagulation. PATIENTS/METHODS: This was a multicenter open-label randomized controlled trial in patients with VICC of FFP vs. no FFP within 4 h of antivenom administration. Patients (> 2 years) recruited to the Australian snakebite project with VICC (International Normalized Ratio [INR] > 3) were eligible. Patients were randomized 2 : 1 to receive FFP or no FFP. The primary outcome was the proportion with an INR of < 2 at 6 h after antivenom administration. Secondary outcomes included time from antivenom administration to discharge, adverse effects, major hemorrhage, and death. RESULTS: Of 70 eligible patients, 65 consented to be randomized: 41 to FFP, and 24 to no FFP. Six hours after antivenom administration, more patients randomized to FFP had an INR of < 2 (30/41 [73%] vs. 6/24 [25%]; absolute difference, 48%; 95% confidence interval 23-73%; P = 0.0002). The median time from antivenom administration to discharge was similar (34 h, range 14-230 h vs. 39 h, range 14-321 h; P = 0.44). Seven patients developed systemic hypersensitivity reactions after antivenom administration - two mild and one severe (FFP arm), and three mild and one severe (no FFP). One serious adverse event (intracranial hemorrhage and death) occurred in an FFP patient with pre-existing hypertension, who was hypertensive on admission, and developed a headache 6 h after FFP administration. Post hoc analysis showed that the median time from bite to FFP administration was significantly shorter for non-responders to FFP than for responders (4.7 h, interquartile range [IQR] 4.2-6.7 h vs. 7.3 h, IQR 6.1-8 h; P = 0.002). CONCLUSIONS: FFP administration after antivenom administration results in more rapid restoration of clotting function in most patients, but no decrease in discharge time. Early FFP administration (< 6-8 h) post-bite is less likely to be effective.


Subject(s)
Antivenins/therapeutic use , Blood Coagulation/drug effects , Blood Transfusion/methods , Disseminated Intravascular Coagulation/therapy , Plasma , Snake Bites/therapy , Snake Venoms , Adolescent , Adult , Animals , Antivenins/adverse effects , Australia , Combined Modality Therapy , Disseminated Intravascular Coagulation/blood , Disseminated Intravascular Coagulation/etiology , Disseminated Intravascular Coagulation/mortality , Female , Hemorrhage/etiology , Hemorrhage/mortality , Hemorrhage/prevention & control , Humans , International Normalized Ratio , Length of Stay , Male , Middle Aged , Patient Discharge , Snake Bites/blood , Snake Bites/complications , Snake Bites/mortality , Time Factors , Time-to-Treatment , Treatment Outcome , Young Adult
8.
Indoor Air ; 23(3): 196-207, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23167831

ABSTRACT

UNLABELLED: Concern for the exposure of children attending schools located near busy roadways to toxic, traffic-related air pollutants has raised questions regarding the environmental benefits of advanced heating, ventilation, and air-conditioning (HVAC) filtration systems for near-road pollution. Levels of black carbon and gaseous pollutants were measured at three indoor classroom sites and at seven outdoor monitoring sites at Las Vegas schools. Initial HVAC filtration systems effected a 31-66% reduction in black carbon particle concentrations inside three schools compared with ambient air concentrations. After improved filtration systems were installed, black carbon particle concentrations were reduced by 74-97% inside three classrooms relative to ambient air concentrations. Average black carbon particle concentrations inside the schools with improved filtration systems were lower than typical ambient Las Vegas concentrations by 49-96%. Gaseous pollutants were higher indoors than outdoors. The higher indoor concentrations most likely originated at least partially from indoor sources, which were not targeted as part of this intervention. PRACTICAL IMPLICATIONS: Recent literature has demonstrated adverse health effects in subjects exposed to ambient air near major roadways. Current smart growth planning and infill development often require that buildings such as schools are built near major roadways. Improving the filtration systems of a school's HVAC system was shown to decrease children's exposure to near-roadway diesel particulate matter. However, reducing exposure to the gas-phase air toxics, which primarily originated from indoor sources, may require multiple filter passes on recirculated air.


Subject(s)
Air Filters , Air Pollutants/analysis , Air Pollution, Indoor/prevention & control , Vehicle Emissions/analysis , Ventilation , Air Pollution, Indoor/analysis , Benzene/analysis , Butadienes/analysis , Carbon/analysis , Nevada , Schools/statistics & numerical data , Toluene/analysis
9.
QJM ; 105(11): 1089-95, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22875778

ABSTRACT

BACKGROUND: Snakebites in snake handlers are an important clinical problem that may differ to bites in the general population. AIM: To investigate the epidemiology and clinical presentation of bites in snake handlers. DESIGN: Prospective observational study. METHODS: Bites in snake handlers recruited as part of the Australian Snakebite Project (ASP) from 2004 to 2011 were included in the study. Data were extracted from the ASP database, which included demographic and clinical information, laboratory tests and antivenom treatment. RESULTS: From 1089 snake bites recruited to ASP, there were 106 (9.7%) bites in snake handlers. The median age was 40 years (range: 16-81 years) and 104 (98%) were males. The commonest circumstances of the bites were handling snakes (47), catching snakes (22), feeding snakes (18) and cleaning cages (11). Bites were to the upper limb in 103 cases. Bites were most commonly by Red-bellied black snakes (20), Brown snakes (17), Taipan (15), Tiger snakes (14) and Death adders (14). Envenoming occurred in 77 patients: venom-induced consumption coagulopathy in 45 patients (58%), neurotoxicity in 10 (13%) and myotoxicity in 13 (17%). Systemic hypersensitivity reactions (SHSRs) to venom occurred in eight, satisfying clinical criteria for anaphylaxis in five, of which three were hypotensive. Antivenom was administered in 60 envenomed patients. SHSRs to antivenom occurred in 15 (25%; 95% CI:15-38%), including 2 (3%:1-13%) with severe (hypotensive) reactions. CONCLUSION: Bites in snake handlers remain a common, important problem involving a broad range of snakes. Neurotoxicity and myotoxicity are relatively common, consistent with the snakes involved. Venom anaphylaxis occured, despite previously being a poorly recognized problem in snake handlers. The incidence of SHSRs to antivenoms, including anaphylaxis, was not higher than that observed in non-snake handlers.


Subject(s)
Hypersensitivity, Immediate/epidemiology , Nervous System Diseases/epidemiology , Occupational Diseases/diagnosis , Occupational Diseases/epidemiology , Severity of Illness Index , Snake Bites/diagnosis , Snake Bites/epidemiology , Adult , Aged , Aged, 80 and over , Anaphylaxis/epidemiology , Animal Technicians/statistics & numerical data , Antivenins/therapeutic use , Australia/epidemiology , Causality , Female , Humans , Hypersensitivity/epidemiology , Incidence , Male , Middle Aged , Occupational Diseases/drug therapy , Prognosis , Prospective Studies , Risk Factors , Snake Bites/drug therapy , Time Factors , Young Adult
11.
Toxicon ; 58(8): 634-40, 2011 Dec 01.
Article in English | MEDLINE | ID: mdl-21967812

ABSTRACT

There is limited information on envenoming by snakes of the genus Hoplocephalus from Eastern Australia. We investigated the clinical and laboratory features of patients with definite Hoplocephalus spp. bites including antivenom treatment, recruited to the Australian Snakebite Project. There were 15 definite Hoplocephalus spp. bites based on expert identification including eight by Hoplocephalus stephensi (Stephen's banded snakes), four by Hoplocephalus bungaroides (broad-headed snake) and three by H. bitorquatus (pale-headed snake). Envenoming occurred in 13 patients and was similar for the three species with venom induced consumption coagulopathy (VICC) in all envenomings. Seven patients had an INR >12 and partial VICC, with only incomplete fibrinogen consumption, occurred in three patients. Systemic symptoms occurred in eight patients. Myotoxicity and neurotoxicity did not occur. H. stephensi venom was detected in all three H. stephensi envenomings (1.1, 44 and 81 ng/mL) for whom pre-antivenom blood samples were available, and not detected in one without envenoming. In two cases with post-antivenom blood samples, venom was not detected after tiger snake antivenom (TSAV) was given. In vitro binding studies demonstrated that TSAV concentrations of 50mU/mL are sufficient to bind the majority of free H. stephensi venom components at concentrations above those detected in envenomed patients (100 ng/mL). Eleven patients received antivenom, median dose 2 vials (Range: 1 to 5 vials), which was TSAV in all but one case, where polyvalent antivenom was used. Immediate hypersensitivity reactions occurred in six cases including one case of anaphylaxis. Envenoming by Hoplocephalus spp. causes VICC and systemic symptoms, making it clinically similar to brown snake (Pseudonaja spp.) envenoming. Based on in vitro studies reported here, patients may be treated with one vial of TSAV, although one vial of brown snake antivenom may also be sufficient.


Subject(s)
Antivenins/pharmacology , Blood Coagulation/drug effects , Elapid Venoms/toxicity , Elapidae , Immunologic Factors/pharmacology , Neurotoxins/toxicity , Snake Bites/drug therapy , Adolescent , Adult , Animals , Antivenins/adverse effects , Antivenins/metabolism , Australia , Child , Cohort Studies , Elapid Venoms/metabolism , Humans , Hypersensitivity/etiology , Immunologic Factors/adverse effects , Immunologic Factors/metabolism , Male , Middle Aged , Neurotoxins/metabolism , Prospective Studies , Protein Binding , Young Adult
12.
Toxicon ; 58(4): 304-14, 2011 Sep 15.
Article in English | MEDLINE | ID: mdl-21824487

ABSTRACT

OBJECTIVE: To assess histopathological changes in clinically envenomed tiger snake patients and identify tissue specific localisation of venom toxins using immunohistochemistry. SAMPLES: One feline and one canine patient admitted to the Murdoch Pet Emergency Centre (MPEC), Murdoch University with tiger snake (Notechis sp.) envenoming. Both patients died as a result of envenomation. Non-envenomed tissue was also collected and used for comparison. METHODOLOGY: Biopsy samples (heart, lung, kidney andskeletal muscle tissue) were retrieved 1-2 h post death and processed for histopathological examination using Haemotoxylin and Eosin, Martius Scarlet Blue and Periodic Acid Schiff staining. Tissues were examined by light microscopy and tissue sections subjected to immunohistochemical staining using in-house generated monoclonal and polyclonal antibodies against Notechis venoms. RESULTS: Venom-induced pathological changes were observed in the lungs, kidneys and muscle tissue of both patients. Evidence, not previously noted, of procoagulant venom effects were apparent, with formed thrombi in the heart, lungs (small fibrillar aggregates and larger, discrete thrombi) and kidneys. Immunohistochemical assays revealed venom present in the pulmonary tissue, in and around the glomerular capsule and surrounding tubules in renal tissue and scattered throughout the Gastrocnemius muscle tissue. CONCLUSION: This work has shown pathological evidence of procoagulant venom activity supporting previous suggestions that an initial thrombotic state occurs in envenomed patients. We have shown that venom toxins are able to be localised to specific tissues, in this case, venom was detected in the lung, kidney and muscle tissues of clinically envenomed animals. Future work will examine specific toxin localisation using monoclonal antibodies and identify if antivenom molecules are able to reach their target tissues.


Subject(s)
Cat Diseases/pathology , Dog Diseases/pathology , Elapid Venoms/toxicity , Snake Bites/veterinary , Animals , Blood Coagulation/drug effects , Cat Diseases/chemically induced , Cats , Dog Diseases/chemically induced , Dogs , Elapid Venoms/analysis , Female , Heart/drug effects , Immunohistochemistry , Kidney/drug effects , Kidney/pathology , Lung/drug effects , Lung/pathology , Male , Muscle, Skeletal/drug effects , Muscle, Skeletal/pathology , Myocardium/pathology , Snake Bites/pathology
13.
Laterality ; 16(6): 707-21, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21391106

ABSTRACT

The current study investigated (a) whether or not the WatHand Cabinet Test (WHCT, Bryden, Roy, & Spence, 2007) could be used as accurately as the Waterloo Handedness Questionnaire (WHQ) to classify individuals into language lateralisation groups based on their hand preference, and (b) the relationship between direction and degree of hand preference and language lateralisation. A total of 142 participants (82 right-handers and 60 left-handers) completed the WHQ and the WHCT, and performed a fused-words dichotic listening test. Findings indicated that the WHCT was robust alternative to the WHQ in providing a measure of hand preference as there was a high correlation between the WHCT and the WHQ, and individuals were divided into similar language lateralisation groups when using either the WHCT or the WHQ as the classifying variable. More specifically, there existed a predictable pattern of language lateralisation into which members of different handedness groups fell. The same pattern exists whether handedness is defined using subjective questionnaires or more objective observational measures of hand preference.


Subject(s)
Dichotic Listening Tests/psychology , Dominance, Cerebral/physiology , Functional Laterality/physiology , Language , Surveys and Questionnaires/standards , Verbal Behavior/physiology , Bias , Female , Humans , Male
14.
J Thromb Haemost ; 8(11): 2504-13, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20831619

ABSTRACT

BACKGROUND: Limited information exists on the dynamics of hemostasis in patients with venom-induced consumption coagulopathy (VICC) from snake envenomation. OBJECTIVE: The aim of the present study was to investigate specific factor deficiencies and their time course in Australasian elapid envenomation. METHODS: We measured coagulation parameters and factor concentrations in patients recruited to the Australian Snakebite Project, an observational cohort study. There were 112 patients with complete VICC, defined as an international normalized ratio (INR) > 3, and 18 with partial VICC. Serial citrated plasma samples were collected from 0.5 to 60 h post-bite. INR, activated partial thromboplastin time (aPTT), coagulation factors (F)I, II, V, VII, VIII, IX, X, von Willebrand factor antigen (VWF:Ag) and D-dimer concentrations were measured. RESULTS: Complete VICC was characterized by near/total depletion of fibrinogen, FV and FVIII, with an INR and aPTT that exceeded the upper limits of detection, within 2 h of snakebite. Prothrombin levels never fell below 60% of normal, suggesting that the toxins were rapidly eliminated or inactivated and re-synthesis of clotting factors occurred irrespective of antivenom. Partial VICC caused limited depletion of fibrinogen and FV, and almost complete consumption of FVIII. Onset of VICC was more rapid with brown snake (Pseudonaja spp.) venom, which contains a group C prothrombin activator toxin, compared with the tiger snake group, which contains a group D prothrombin activator toxin and requires human FVa formation. Resolution of VICC occurred within 24-36 h irrespective of snake type. CONCLUSIONS: These results suggest that Australasian elapid prothrombin activators have a potent but short duration of action. Antivenom is unlikely to be administered in time to prevent VICC.


Subject(s)
Disseminated Intravascular Coagulation/blood , Snake Bites/blood , Adolescent , Adult , Aged , Aged, 80 and over , Animals , Antivenins/pharmacology , Australia , Blood Coagulation/drug effects , Blood Coagulation Factors/metabolism , Child , Child, Preschool , Cohort Studies , Disseminated Intravascular Coagulation/etiology , Female , Humans , International Normalized Ratio , Male , Middle Aged , Partial Thromboplastin Time , Time Factors , Venoms
15.
Toxicon ; 55(8): 1510-8, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20223258

ABSTRACT

The detection and measurement of snake venom in blood is important for confirming snake identification, determining when sufficient antivenom has been given, detecting recurrence of envenoming, and in forensic investigation. Venom enzyme immunoassays (EIA) have had persistent problems with poor sensitivity and high background absorbance leading to false positive results. This is particularly problematic with Australasian snakes where small amounts of highly potent venom are injected, resulting in low concentrations being associated with severe clinical effects. We aimed to develop a venom EIA with a limit of detection (LoD) sufficient to accurately distinguish mild envenoming from background absorbance at picogram concentrations of venom in blood. Serum samples were obtained from patients with taipan bites (Oxyuranus spp.) before and after antivenom, and from rats given known venom doses. A sandwich EIA was developed using biotinylated rabbit anti-snake venom antibodies for detection. For low venom concentrations (i.e. <1 ng/mL) the assay was done before and after addition of antivenom to the sample (antivenom difference method). The LoD was 0.15 ng/mL for the standard assay and 0.1 ng/mL for the antivenom difference method. In 11 pre-antivenom samples the median venom concentration was 10 ng/mL (Range: 0.3-3212 ng/mL). In four patients with incomplete venom-induced consumption coagulopathy the median venom concentration was 2.4 ng/mL compared to 30 ng/mL in seven patients with complete venom-induced consumption coagulopathy. No venom was detected in any post-antivenom sample and the median antivenom dose prior to this first post-antivenom sample was 1.5 vials (1-3 vials), including 7 patients administered only 1 vial. In rats the assay distinguished a 3-fold difference in venom dose administered and there was small inter-individual variability. There was small but measurable cross-reactivity with black snake (Pseudechis), tiger snake (Notechis) and rough-scale snake (Tropidechis carinatus) venoms with the assay for low venom concentrations (<1 ng/mL). The use of biotinylation and the antivenom difference method in venom EIA produces a highly sensitive assay that will be useful for determining antivenom dose, forensic and clinical diagnosis.


Subject(s)
Elapid Venoms/blood , Elapidae/physiology , Immunoenzyme Techniques , Snake Bites/diagnosis , Adult , Aged , Animals , Antivenins/therapeutic use , Child , Child, Preschool , Cross Reactions , Elapid Venoms/immunology , Elapid Venoms/poisoning , Female , Humans , Limit of Detection , Male , Middle Aged , Predictive Value of Tests , Rabbits , Rats , Snake Bites/blood , Snake Bites/therapy , Young Adult
16.
Diabetologia ; 52(9): 1808-15, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19575177

ABSTRACT

AIMS/HYPOTHESIS: The aim was to investigate the relationship between severe hypoglycaemia and cognitive impairment in older patients with diabetes. METHODS: A sample of 302 diabetic patients aged >/=70 years was assessed for dementia or cognitive impairment without dementia in 2001-2002 and a subsample of non-demented patients (n = 205) was followed to assess cognitive decline. A history of severe hypoglycaemia was determined from self-reports, physician assessments and records of health service use for hypoglycaemia (HSH). Prospective HSH was determined up to 2006. Data analysis, including multiple logistic and Cox regression models, was used to determine whether: (1) there were cross-sectional associations between hypoglycaemia and cognitive status, (2) historical hypoglycaemia predicted cognitive decline, and (3) baseline cognitive status predicted subsequent HSH. RESULTS: There were significant cross-sectional associations between both cognitive impairment and dementia and hypoglycaemia. Independent risk factors for future HSH included dementia (hazard ratio 3.00, 95% CI 1.06-8.48) and inability to self-manage medications (hazard ratio 4.17, 95% CI 1.43-12.13). However, there were no significant associations between historical hypoglycaemia, incident HSH and cognitive decline. CONCLUSIONS/INTERPRETATION: Dementia is an important risk factor for hypoglycaemia requiring health service utilisation. We found no evidence that hypoglycaemia contributes to cognitive impairment in older patients with diabetes.


Subject(s)
Cognition Disorders/epidemiology , Diabetes Complications/epidemiology , Hypoglycemia/epidemiology , Aged , Aged, 80 and over , Cognition Disorders/mortality , Dementia/epidemiology , Diabetes Complications/mortality , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/epidemiology , Female , Glycated Hemoglobin/analysis , Humans , Hypoglycemia/mortality , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use , Male , Mental Status Schedule , Patient Selection , Predictive Value of Tests , Prevalence , Probability , Regression Analysis , Sulfonylurea Compounds/therapeutic use , Surveys and Questionnaires , Survival Rate , Western Australia
17.
QJM ; 102(8): 563-8, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19570990

ABSTRACT

BACKGROUND: Venom-induced consumption coagulopathy (VICC) is an important feature of snake envenoming. AIM: To investigate the effect of antivenom and fresh frozen plasma (FFP) on recovery of VICC in Australian elapid snake envenoming. DESIGN: Prospective cohort study. METHODS: Patients with VICC were included from the Australian Snakebite Project (ASP). Time to recovery of VICC (defined as time until INR <2) was investigated using a time to event analysis in WinBUGS. The model considered the effects of age, sex, snake type, time of antivenom after bite, antivenom dose and use of FFP within 4 h. RESULTS: The study included 167 cases of VICC, median age being 41 [interquartile range (IQR): 28-53) years, and 130 (78%) were males. Antivenom was administered at a median of 3.6 (IQR: 2.2-5.6) h after the bite at a median dose of four vials (IQR: 2-6 vials). Thirteen patients received FFP within 4 h. Recovery of VICC occurred after a median of 14.4 (IQR: 11.5-17.5) h, and only the use of FFP within 4 h influenced the time to recovery. Neither antivenom dose nor time of antivenom administration had an effect on recovery of VICC. In patients administered with FFP, 12% [credible interval (CrI): 6-21%] and 81% (CrI: 61-94%) had recovered at 6 and 12 h, respectively, vs 2.5% (CrI: 1.5-4%) and 28% (CrI: 22-34%) not receiving FFP. DISCUSSION: Antivenom did not appear to be effective for the coagulopathy in snake envenoming in Australia. FFP appeared to shorten the time of VICC recovery.


Subject(s)
Antivenins/administration & dosage , Disseminated Intravascular Coagulation/therapy , Plasma , Snake Bites/complications , Adult , Age Factors , Australia , Blood Coagulation/drug effects , Disseminated Intravascular Coagulation/blood , Disseminated Intravascular Coagulation/etiology , Dose-Response Relationship, Drug , Female , Humans , Male , Middle Aged , Prospective Studies , Sex Factors , Treatment Outcome
19.
J Physiol ; 587(Pt 13): 3159-73, 2009 Jul 01.
Article in English | MEDLINE | ID: mdl-19403603

ABSTRACT

Influenza A viruses cause lung disease via an incompletely understood mechanism that involves the accumulation of liquid within the lungs. The accumulation of lung liquid is normally prevented by epithelial Na(+) absorption, a transport process regulated via several pathways including phosphoinositide-3-kinase (PI3K). Since the influenza A virus encodes a non-structural protein (NS1) that can activate this kinase, we now explore the effects of NS1 upon the biophysical properties of human airway epithelial cells. Transient expression of NS1 depolarized electrically isolated cells maintained in glucocorticoid-free medium by activating a cation conductance identical to the glucocorticoid-induced conductance seen in single cells. This response involved PI3K-independent and PI3K-dependent mechanisms. Infecting glucocorticoid-deprived cells with influenza A virus disrupted the normal electrical coupling between neighbouring cells, but also activated a conductance identical to that induced by NS1. This response to virus infection was only partially dependent upon NS1-mediated activation of PI3K. The presence of NS1 allows influenza A to modify the biophysical properties of infected cells by activating a Na(+)-permeable conductance. Whilst the activation of Na(+)-permeable channels may be expected to increase the rate of Na(+) absorption and thus reduce the volume of liquid in the lung, liquid does normally accumulate in influenza A-infected lungs. The overall effect of influenza A on lung liquid volume may therefore reflect a balance between the activation and inhibition of Na(+)-permeable channels.


Subject(s)
Influenza A virus/pathogenicity , Ion Channels/metabolism , Respiratory System/metabolism , Respiratory System/virology , Biophysical Phenomena , Cell Line , Dexamethasone/pharmacology , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Epithelial Cells/virology , Humans , Influenza A virus/genetics , Influenza, Human/metabolism , Influenza, Human/virology , Ion Transport/drug effects , Phosphatidylinositol 3-Kinases/metabolism , Respiratory System/cytology , Sodium/metabolism , Transfection , Viral Nonstructural Proteins/genetics , Viral Nonstructural Proteins/toxicity
20.
Allergy ; 64(2): 204-12, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19178399

ABSTRACT

BACKGROUND: Anaphylaxis is a serious allergic reaction that is rapid in onset and may cause death. Adrenaline is recommended as the initial treatment of choice for anaphylaxis. OBJECTIVES: To assess the benefits and harms of adrenaline in the treatment of anaphylaxis. METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2007, Issue 1), MEDLINE (1966 to March 2007), EMBASE (1966 to March 2007), CINAHL (1982 to March 2007), BIOSIS (to March 2007), ISI Web of Knowledge (to March 2007) and LILACS (to March 2007). We also searched websites listing ongoing trials: http://www.clinicaltrials.gov/, http://www.controlledtrials.com and http://www.actr.org.au/ and contacted pharmaceutical companies and international experts in anaphylaxis in an attempt to locate unpublished material. Randomized and quasi-randomized controlled trials comparing adrenaline with no intervention, placebo or other adrenergic agonists were eligible for inclusion. Two authors independently assessed articles for inclusion. RESULTS: We found no studies that satisfied the inclusion criteria. CONCLUSIONS: On the basis of this review, we are unable to make any new recommendations on the use of adrenaline for the treatment of anaphylaxis. In the absence of appropriate trials, we recommend, albeit on the basis of less than optimal evidence, that adrenaline administration by intramuscular injection should still be regarded as first-line treatment for the management of anaphylaxis.


Subject(s)
Adrenergic Agonists/therapeutic use , Anaphylaxis/drug therapy , Epinephrine/therapeutic use , Adrenergic Agonists/administration & dosage , Adrenergic Agonists/immunology , Anaphylaxis/immunology , Databases, Factual , Drug Administration Routes , Epinephrine/administration & dosage , Epinephrine/immunology , Humans , Randomized Controlled Trials as Topic
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