Comparison of adrenaline auto-injector devices: ease of use and ability to recall use.

BACKGROUND: A limited number of adrenaline auto-injectors are currently available. Epipen and Anapen are available in Australia, New Zealand, UK and parts of Europe and Asia. Few studies have compared the performance of these devices. OBJECTIVE: To compare the intuitiveness of use of these devices. A secondary aim was to compare the ability to recall the use of each device after a period of 3 months. METHOD: A random sample of 100 subjects naïve to both the EpiPen and Anapen were recruited from staff and families attending Royal Children's Hospital, Melbourne Australia. Subjects were randomized to Anapen (n = 53) or EpiPen (n = 47) and asked to demonstrate use of a 'trainer' device (i) prior to and (ii) after receiving training in its correct use. A subset (n = 32) participated in a follow-up study to evaluate (iii) the ability to recall correct use of each device. RESULTS: Most subjects correctly demonstrated all steps in use of the EpiPen and Anapen both prior to (89% vs. 79%, p = 0.17) and after training on use (100% vs. 100%). However, after 3 months, significantly more participants correctly demonstrated use of EpiPen (87%) compared to Anapen (35%) (p = 0.003) and critical errors that would likely result in failure to administer adrenaline were more common with Anapen (59% vs. 13%, p = 0.01). CONCLUSION: Most study participants correctly demonstrated the use of both devices without prior training. There was greater attrition in correct use of Anapen compared to EpiPen over time. Critical errors in administration were more likely with Anapen than EpiPen.

The prevalence and socio-demographic risk factors of clinical eczema in infancy: a population-based observational study.

BACKGROUND: Socio-demographic predictors for the development of clinically observed, infantile eczema have not been formally examined in a large population-based study. Few studies of eczema risk factors have included current, objective eczema outcomes as well as parent-reported history. OBJECTIVES: We aimed to measure the population prevalence of infantile eczema using novel sampling methodology, and identify socio-demographic risk factors for eczema in the first year of life. METHODS: A population-based cross-sectional study of infantile allergy (the HealthNuts study, n = 4972, response rate 74.1%) was conducted from 2008-2011 in Melbourne, Australia. Infants were examined for current eczema at age 12 months (mean 12.7, SD 0.7). Parents provided information about the infants' history of eczema and demographic factors. Factors associated with eczema were modelled using multinomial logistic regression. RESULTS: The population prevalence of observed eczema at 12 months was 20.3% (95% CI 19.0, 21.5), while cumulative prevalence for parent-reported eczema was 28.0% (95% CI 26.7, 29.4). The strongest predictors of eczema were maternal eczema and asthma (multinomial (M)-OR 1.7, P < 0.001, and M-OR 1.4, P = 0.007), male sex (M-OR 1.4, P < 0.001), and East Asian ethnicity (M-OR 1.6, P < 0.001) with over 80% of infants with all risk factors exhibiting eczema. East Asian parents, particularly recent migrants, reported fewer allergies than other parents. CONCLUSIONS AND CLINICAL RELEVANCE: Approximately, one in three infants developed eczema by 12 months of age. East Asian infants are at increased risk of eczema despite their parents having lower rates of allergy than non-Asian parents. Gene-environment interactions may explain the differential effect seen in this minority group.

Frequent baked egg ingestion was not associated with change in rate of decline in egg skin prick test in children with challenge confirmed egg allergy.

BACKGROUND: It is controversial whether egg-allergic children should strictly avoid all forms of egg, or if regular ingestion of baked egg will either delay or hasten the resolution of egg allergy. OBJECTIVE: This is the first study to examine the relationship between frequency of baked egg ingestion and rate of decline in egg skin prick test size in egg-allergic children. METHODOLOGY: This was a retrospective clinical cohort study. All children with challenge-proven egg allergy who attended the Royal Children's Hospital Allergy Department 1996-2005 and had at least two egg skin prick tests performed in this period were included (n = 125). Frequency of baked egg ingestion was assessed by telephone questionnaire as follows: (a) frequent (> once per week), (b) regular (> once every 3 months, up to ≤ once per week) or (c) strict avoidance (≤ once every 3 months). The relationship between frequency of baked egg ingestion and rate of decline in egg skin prick test size was examined by multiple linear regression, adjusting for potential confounders. RESULTS: Mean rate of decline in egg skin prick test size in all children was 0.7 mm/year (95% CI 0.5-1.0 mm/year). There was no evidence (P = 0.57) that the rate of decline in egg skin prick test size differed between children who undertook frequent ingestion (n = 21, mean 0.4 mm/year, 95% CI -0.3-1.2 mm/year), regular ingestion (n = 37, mean 0.9 mm/year, 95% CI 0.4-1.4 mm/year) or strict avoidance (n = 67, mean 0.7 mm/year, 95% CI 0.4-1.1 mm/year) of baked egg. CONCLUSIONS: Compared with strict dietary avoidance, frequent consumption of baked egg was not associated with a different rate of decline in egg skin prick test size in egg-allergic children. CLINICAL RELEVANCE: Given that dietary restrictions can adversely impact on the family, it is reasonable to consider liberalizing baked egg in the diet of egg-allergic children.

Environmental and demographic risk factors for egg allergy in a population-based study of infants.

BACKGROUND: Although egg allergy is the most common food allergy in infants and young children, risk factors for egg allergy remain largely unknown. This study examined the relationship between environmental and demographic factors and egg allergy in a population-based infant cohort. METHODS: In a study of 5276 infants (HealthNuts), infants underwent skin prick testing (SPT) to egg white at 12 months of age. Questionnaire data on relevant exposures were obtained. 699/873 (80%) infants eligible for oral food challenge (detectable wheal on SPT) attended for formal assessment of egg allergy status; 453 had confirmed egg allergy (positive challenge and SPT ≥ 2 mm). Associations between environmental and demographic factors and egg allergy were investigated using multivariable logistic regression. RESULTS: Children with older siblings and those with a pet dog at home were less likely to develop egg allergy by 1 year of age (adjusted OR [aOR], 0.72; 95% CI, 0.62, 0.83 per sibling; and aOR, 0.72; 95% CI, 0.52, 0.99, respectively). Caesarean section delivery, antibiotic use in infancy, childcare attendance and maternal age were not associated with egg allergy. History of allergic disease in an immediate family member and having parents born in East Asia were strong risk factors for infantile egg allergy (aOR, 1.82; 95% CI, 1.40, 2.36; and aOR, 3.30; 95% CI, 2.45, 4.45, respectively). CONCLUSIONS: Exposure in the first year of life to siblings and dogs may decrease the risk of subsequent egg allergy. Infants with a family history of allergy and those with parents born in East Asia are at increased risk of egg allergy.

A critical analysis of the fatal injuries resulting from the Continental flight 1713 airline disaster: evidence in favor of improved passenger restraint systems.

OBJECTIVE: To examine the mechanisms of injury and death in a commercial airline disaster and to propose preventative safety measures based on this analysis. DATA SOURCE: Denver County Coroner's Office and the National Transportation Safety Board. STUDY SELECTION: Those patients suffering fatal injuries as a result of the Continental Flight 1713 Airline crash. DATA EXTRACTION: Autopsy records from the Denver County Coroner's Office were reviewed with the causes of death determined. In many instances there was significant injury to more than one anatomic region in a single individual, each analyzed independently. DATA SYNTHESIS: There were 28 fatalities: nine died of mechanical asphyxiation, one of a penetrating cranial injury, and 18 of blunt trauma. The blunt injuries were remarkably similar to the deceleration injuries seen in high-speed motor vehicle crashes. Head trauma was the most common fatal blunt injury, followed by injuries to the chest and the abdomen. Thirty-six percent of the head injuries and 27% of the chest injuries had associated cervical and thoracic spine fractures, respectively. Analysis revealed a marked similarity in injury pattern sustained by seatmates, with a high incidence of fatal and serious injuries suffered by those passengers sitting in the front half of the airplane. CONCLUSIONS: Fatal blunt injury secondary to deceleration forces was the most common cause of death seen in this analysis. The use of a lap belt restraint system alone is not adequate to protect passengers against these forces as shown convincingly in the automotive industry literature. What impact a better passenger restraint system may have had on survival in this disaster is unknown, however, at a minimum, it would have significantly improved survival for 6 of 28 passengers dying of isolated blunt head trauma. Minor alterations in aircraft design (secure bolting of passenger seats to the airplane superstructure) and passenger restraints (3-point lap and shoulder harness system) is proposed to positively influence survival during an airplane crash at negligible increased airline expense or passenger inconvenience.

Electric shock devices and their effects on the human body.

Stun guns, shock batons and cattle prods are electric shock devices which can be used as weapons against the human body. Stun guns cause temporary incapacitation of the body whereas the other devices do not. The electrical outputs of examples of each type of device were measured using a digital storage oscilloscope at the moment when the device was discharged across resistors chosen to simulate the resistance of the human body. The outputs from the stun guns and the non-incapacitating devices have characteristic waveform shapes and magnitudes: significantly, the peak current from the stun guns is two orders of magnitude greater than from the other devices. To understand the possible hazardous effects of these outputs on the human body, the output parameters were related to the available information on the effects of electric currents on the human body and on the electro-immobilization of farm animals.

Solution structure of mitochondrial cytochrome c. I. 1H nuclear magnetic resonance of ferricytochrome c.

The 1H nuclear magnetic resonance spectra of tuna and horse ferricytochromes c have been investigated and the resonances of all amino acid methyl groups have been assigned to specific absorption lines. The assignment procedure involves principally the comparison of one-dimensional nuclear magnetic resonance spectra from a range of homologous ferricytochromes c and does not require a prior knowledge of the secondary or tertiary protein structure. Of the 49 methyl groups of tuna cytochrome c, the assignment of 33 is made without reference to the X-ray crystal structure. The method should therefore be applicable to other proteins of similar size where X-ray structures are unavailable. The assignments will be used to investigate the structure of cytochrome c in solution.

Solution structure of mitochondrial cytochrome c. II. 1H nuclear magnetic resonance of ferrocytochrome c.

The 1H nuclear magnetic resonance spectrum of tuna ferrocytochrome c has been studied and the resonances of all 49 amino acid methyl groups have been assigned to specific absorption lines. In comparison with resonance assignments in the ferricytochrome c spectrum, the secondary shifts of resonances of ferrocytochrome c are smaller and the identification of characteristic spin-systems from comparison of spectra from homologous proteins more difficult. For this reason, two-dimensional nuclear magnetic resonance exchange correlated spectroscopy has been used to correlate the assigned resonances of tuna ferricytochrome c with previously unassigned resonances of tuna ferrocytochrome c.

The conformation of eukaryotic cytochrome c around residues 39, 57, 59 and 74.

1H-n.m.r. studies of horse, tuna, Candida krusei and Saccharomyces cerevisiae cytochromes c showed that each of the proteins contains a similar cluster of residues at the bottom of the protein that assists in shielding the haem from the solvent. The relative positions of the residues forming these clusters vary continuously with temperature, and they change with the change in protein redox state. This conformational heterogeneity is discussed with reference to the conformational flexibility of cytochrome c around residues 57, 59 and 74. Spectroscopic measurements of pKa values for Lys-55 (horse and tuna cytochromes c) and His-33 and His-39 (C. krusei and S. cerevisiae cytochromes c) are in excellent agreement with expectations based on chemical-modification studies of horse cytochrome c. [Bosshard & Zürrer (1980) J. Biol. Chem. 255, 6694-6699] and on the X-ray-crystallographic structure of tuna cytochrome c [Takano & Dickerson (1981) J. Mol. Biol. 153, 79-94, 95-115].

1H NMR studies of eukaryotic cytochrome c. Resonance assignments and iron-hexacyanide-mediated electron exchange.

1H NMR resonance assignments in the spectra of horse, tuna, Neurospora crassa and Candida krusei cytochromes c are described. Assignments have been made using NMR double-resonance techniques in conjunction with electron-exchange experiments, spectral comparison of related proteins, and consideration of the X-ray structure of tuna cytochrome c. Resonances arising from 11 residues of horse cytochrome c have been assigned.