The CREATE project: development of certified reference materials for allergenic products and validation of methods for their quantification

Allergen extracts have been used for diagnosis and treatment of allergy for around 100 years. During the second half of 20th century, the notion increasingly gained foothold that accurate standardization of such extracts is of great importance for improvement of their quality. As a consequence, manufacturers have implemented extensive protocols for standardization and quality control. These protocols have overall IgE-binding potencies as their focus. Unfortunately, each company is using their own in-house reference materials and their own unique units to express potencies. This does not facilitate comparison of different products. During the last decades, most major allergens of relevant allergen sources have been identified and it has been established that effective immunotherapy requires certain minimum quantities of these allergens to be present in the administered maintenance dose. Therefore, the idea developed to introduce major allergens measurements into standardization protocols. Such protocols based on mass units of major allergen, quantify the active ingredients of the treatment and will at the same time allow comparison of competitor products. In 2001, an EU funded project, the CREATE project, was started to support introduction of major allergen based standardization. The aim of the project was to evaluate the use of recombinant allergens as reference materials and of ELISA assays for major allergen measurements. This paper gives an overview of the achievements of the CREATE project.

Dietary intake in sensitized children with recurrent wheeze and healthy controls: a nested case-control study

BACKGROUND

The rising prevalence of asthma and allergic disease remains unexplained. Several risk factors have been implicated including diet, in particular poly-unsaturated fats and antioxidant intake.

METHODS

A nested case-control study comparing the dietary intake of sensitized children with recurrent wheeze (age 3-5 years) and nonsensitized children who had never wheezed was carried out within an unselected population-based cohort. Cases and controls were matched for age, sex, parental atopy, indoor allergen exposure and pet ownership. Dietary intake was assessed using a validated semi-quantitative food frequency questionnaire and nutrient analysis program.

RESULTS

Thirty-seven case-control pairs (23 male, mean age 4.4 years) participated. Daily total polyunsaturated fat intake was significantly higher in sensitized wheezers (g/day, geometric mean, 95% confidence intervals: 7.1, 6.4-7.9) compared with nonsensitized nonwheezy children (5.6, 5.0-6.3, P = 0.003). Daily omega-3 and omega-6 fat intakes were not significantly different between the two groups. No significant differences were found in intake of any antioxidant or antioxidant cofactors between the groups.

CONCLUSIONS

Young sensitized wheezy children had a significantly higher total polyunsaturated fat intake compared with nonsensitized nonwheezy children. However, we were unable to distinguish a significant difference in specific poly-unsaturated fat intakes. Otherwise the children in both groups had a very similar nutritional intake.

Development of activity standard for 90Y microspheres

(90)Y microspheres are important therapeutic radiopharmaceuticals used in the treatment of liver cancer through a process known as selective internal radiation therapy. SIR-spheres is a radiopharmaceutical product that is comprised of (90)Y microspheres suspended in sterile, pyrogen-free water for injection into patients. It is necessary to establish for the SIR-spheres production the capability of accurately measuring the activity of this product to a traceable national measurement standard. An activity standard for SIR-spheres was developed from a standard for (90)Y solution, employing a highly quantifiable chemical digestion process. Calibration factors for the manufacturer's ionisation chambers were determined for 1 and 5 ml of the SIR-spheres product placed in Wheaton vials, for both 34% and 44% of (90)Y microsphere concentration.

Contemplating choice: attitudes towards intervening in human reproduction in Sri Lanka

To date, relatively little is known about the ethical, legal and social responses to recent advances in reproductive and genetic technology outside Europe and North America. This article reports on a survey carried out among doctors (n=278) and medical students (n=1256) in Sri Lanka to find out more about their responses to novel interventions in human reproduction such as In-Vitro Fertilization, Pre-Implantation Genetic Diagnosis and genetic engineering. In the first part of the paper comparisons are drawn between this survey and a survey carried out in 1985 which also considered issues surrounding amniocentesis and therapeutic termination. The second part of the paper deals with more recent developments. The analysis reveals high levels of support for the use of new technologies in treating infertility and identifying genetic disorders. However, differences are apparent among the major religious communities represented in the sample and these are particularly in evidence in relation to prenatal genetic diagnosis. An important theme throughout both surveys is the continuing tension surrounding State policy and termination of pregnancy and the implications this has for the development of screening and counseling services where genetic disorders are concerned.

Stringent environmental control in pregnancy and early life: the long-term effects on mite, cat and dog allergen

BACKGROUND

As part of a primary prevention of asthma study, we measured the effect of environmental control measures on Der p 1, Fel d 1 and Can f 1 over a 3.5-year period.

METHODS

High-risk infants (both parents atopic) without pets, were randomized to the Active group (n = 142, vinyl flooring in child's room, allergen-impermeable cot mattress, hot-washable toy, mite allergen-impermeable encasings to parental bed and to child's bed when older, high filtration vacuum cleaner, hot-washing of bedding) or the Control group (n = 136, no intervention), in early pregnancy. Dust samples from the parental mattress, living room floor, child's mattress and floor at baseline (pregnancy), birth and at 3 years were analysed for Der p 1, Fel d 1 and Can f 1.

RESULTS

A total of 278 families completed the baseline visit, 259 the birth visit and 239 the 3-year visit. In the Active group at 3 years, 58% remained compliant with all measures likely to reduce the child's exposure to allergen and 77% of parents still used encasings on their bed. Levels of Der p 1, Fel d 1 and Can f 1 were significantly lower in the Active group in the child's floor and the child's mattress at 3 years compared to the Control group (P < 0.001). For the parental mattress, the levels of Der p 1 and Fel d 1 were lower in the Active group (P < 0.001) and there was a strong trend towards a lower level for Can f 1. There was no difference in the levels of any of the allergens between the groups in the living room floor. Childrens' bedrooms with no detectable mite, cat or dog allergen were significantly more common in the Active than the Control group (25 vs. 2, P < 0.001).

CONCLUSIONS

Environmental control measures are effective in substantially reducing levels of Der p 1, Fel d 1 and Can f 1 in homes without pets in the long term and are acceptable to families. The effect of this environmental manipulation on the development of sensitization and allergic disease remains to be seen.

Effect of chemical etching and aging in boiling water on the corrosion resistance of Nitinol wires with black oxide resulting from manufacturing process

The effect of chemical etching in a HF/HNO(3) acid solution and aging in boiling water on the corrosion resistance of Nitinol wires with black oxide has been evaluated with the use of potentiodynamic, modified potentiostatic ASTM F746, and scratch tests. Scanning-electron microscopy, elemental XPS, and Auger analysis were employed to characterize surface alterations induced by surface treatment and corrosion testing. The effect of aging in boiling water on the temperatures of martensitic transformations and shape recovery was evaluated by means of measuring the wire electroresistance. After corrosion tests, as-received wires revealed uniformly cracked surfaces reminiscent of the stress-corrosion-cracking phenomenon. These wires exhibited negative breakdown potentials in potentiostatic tests and variable breakdown potentials in potentiodynamic tests (- 100 mV to + 400 mV versus SCE). Wires with treated surfaces did not reveal cracking or other traces of corrosion attacks in potentiodynamic tests up to + 900-1400-mV potentials and no pitting after stimulation at + 800 mV in potentiostatic tests. They exhibited corrosion behavior satisfactory for medical applications. Significant improvement of corrosion parameters was observed on the reverse scans in potentiodynamic tests after exposure of treated wires to potentials > 1000 mV. In scratch tests, the prepared surfaces repassivated only at low potentials, comparable to that of stainless steel. Tremendous improvement of the corrosion behavior of treated Nitinol wires is associated with the removal of defect surface material and the growth of stable TiO(2) oxide. The role of precipitates in the corrosion resistance of Nitinol-scratch repassivation capacity in particular-is emphasized in the discussion.

Household characteristics and mite allergen levels in Manchester,UK

BACKGROUND

Mite allergen levels vary enormously between different homes in the same geographical area. No large scale studies of mite levels in Manchester homes has been conducted to identify factors associated with higher levels.

OBJECTIVES

To quantify exposure to mite allergens and to identify characteristics associated with higher Der p 1 levels in a large sample of homes in Manchester, UK.

METHODS

Der p 1 was measured in dust from the living room floor, sofa, bedroom floor and mattress in 564 homes. Data on household characteristics were collected by administering a questionnaire. Univariate and multivariate analyses were performed to identify household characteristics associated with higher mite allergen levels.

RESULTS

Der p 1 levels were highest in the mattress (GM 1.19 microg/g, 95% CI 0.98-1.45, P < 0.001). Two-thirds of homes contained Der p 1 levels > 2 microg/g in at least one dust reservoir, and 40.3% contained Der p 1 greater than 10 microg/g. There was a large range in Der p 1 levels between homes (> 10(3)-fold). Damp and condensation were common findings in homes. In the multivariate analyses, factors associated with higher Der p 1 levels in more than one dust reservoir were older homes, older living room carpets, damp, condensation and mixed glazing. Older mattresses were associated with higher mite allergen levels in the mattress where the age of the mattress was recorded. Twenty-four homes contained no detectable mite allergen, six of which reported damp.

CONCLUSIONS

Mite allergen levels are high enough in two of every three homes to be associated with an increase in the risk of sensitization to mite. Factors such as older homes, carpets and mattresses, damp and condensation are associated with higher mite allergen. However, mite allergen levels are occasionally unpredictably very low in homes with risk factors for high levels.

Ethical regulation and the new reproductive technologies in Sri Lanka: perspectives of ethics committee members

OBJECTIVE

To report on part of a pilot study done to explore ethical responses to the new reproductive technologies in Sri Lanka.

DESIGN

Semi-structured interviews carried out with the members of three committees responsible for ethical review of medical research. Members were asked for their views on the ethical, social and legal implications of the new reproductive and genetic technologies. Members' responses were subject to a simple content analysis.

CONCLUSIONS

There was broad acceptance of the new technologies among respondents, but anxieties about potential abuses. Respondents felt that a national committee should regulate practice and monitor future policy.

Organizational factors influencing nurse practitioners' role implementation in acute care settings

The purpose of this study was to explore the influence of organizational factors on the Acute Care Nurse Practitioner (ACNP) role implementation. A descriptive correlational design, incorporating quantitative and qualitative methods for data collection was used. The sample of convenience consisted of 57 ACNPs assigned to various medical and surgical programs within acute care hospitals. Ten ACNPs participated in the unstructured qualitative interviews. In addition to the interviews, data pertinent to various organizational factors, including role formalization, receptivity of the role by others, perceived autonomy, role strain, and additional factors that may interfere with role implementation, were collected through a self-report structured questionnaire. A four-diary day was completed to gather data on role implementation. Descriptive and correlational statistics were used to analyze the quantitative data. The qualitative data were content analyzed. The ACNPs engaged most frequently in activities reflective of the clinical practice component of the role and less frequently in the non-clinical components (i.e., education, administration, and research). Results of the quantitative and qualitative analyses indicated that lack of formal clear job description, conflicting demands and expectations, lack of receptivity of the role by others, lack of autonomy, and increased workload were negatively correlated with the ACNP role implementation. The ACNP role implementation varies across practice settings. This variability should be accounted for when examining outcomes of ACNP care.

Practice patterns of acute care nurse practitioners

This study was undertaken to examine the practice pattern of nurse practitioners employed in Ontario acute care settings. A descriptive design, incorporating quantitative and qualitative methods for data collection, was used. The acute care nurse practitioners' practice pattern varied in terms of scope of practice, model guiding practice, reporting relations, and extent of role implementation. Role implementation encompassed activities representing the four role components: clinical practice, education, administration or management, and research. The acute care nurse practitioners engaged most frequently in the clinical component of the role. They performed medical and advanced nursing functions. They emphasized that they do not work in isolation and that they do not replace physicians or residents.

Synthetic pillows contain higher levels of cat and dog allergen than feather pillows

The use of non-feather pillows has increased over the last few decades. Recently, we found significantly higher levels of dust mite allergens in synthetic pillows than in feather ones. This study investigated the levels of pet allergens in feather and synthetic pillows. Dust samples were collected from 14 pairs of pillows (consisting of one synthetic fibre-filled and one feather-filled). Each pair of pillows had been on the same bed for at least 2 years. The pillows were vacuumed for 1 min on each side through a 355-microm diameter mesh onto a 5-microm vinyl filter, producing a sample of fine dust. Samples were extracted, and cat (Fel d 1) and dog (Can f 1) allergens determined using monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA). Results were expressed both as total amount of allergen recovered and concentration of allergen per unit weight (ng/g). Total levels of pet allergens were significantly higher in the synthetic pillows (Fel d 1: 6.7-fold difference [95% CI 1.5-29.7], p=0.01; Can f 1: 8-fold difference [95% CI 1.6-39.5], p=0.01). Similarly, when the results were expressed as ng/g, synthetic pillows contained significantly more allergens than feather pillows (Fel d 1: 3.7-fold difference [95% CI 1.3-10.1], p=0.01); Can f 1: 4.4-fold difference [95% CI 1.5-13.2], p=0.01). We have therefore demonstrated that synthetic pillows contain significantly more pet allergens than feather pillows, supporting the view that tightly woven encasements surrounding feather pillows act as a barrier for allergens.

Veterinary vaccines: In-VITRO--International Veterinary Industry Test Replacement Organisation

The International Veterinary Industry Test Replacement Organisation (In-VITRO) was established in 1995 with the aim of developing, validating and harmonising in vitro alternatives to replace in vivo methods for in-process and potency testing of veterinary clostridial vaccines. The emphasis has been on the reduction of animal usage in the Clostridium chauvoei potency assay and its eventual replacement by an in vitro assay. Replacement of the toxin neutralisation assay for Cl. tetani by an internationally validated indirect ELISA has already started. A validation programme involving a collaboration organised through EDQM which could ultimately lead to the standardisation of in vitro tests for all clostridial vaccines is in progress. In addition In-VITRO is now considering the setting up of a programme for Erysipelas vaccines. The collaboration between manufacturers of veterinary vaccines in the development and validation of in vitro tests is a major step towards the reduction and replacement of animal tests.

Measuring quality in hospitals: is there a difference between for-profits and not-for-profits?

Health care professionals agree that by measuring quality, improvements can be made in care delivery. There are measurable differences between not-for-profit and for-profit hospitals, both in public perception and care outcomes. The ability by consumers, insurers and providers to easily access quality data will drive the health care industry to take a quality focus in their daily business. Quality providers with measurable results will gain a larger share of health care dollars and consumer trust. Physicians will choose to partner with the quality leaders and will refine their practices as part of the quality evolution.

Controlled trial of two formulations of cromolyn sodium in the treatment of asthmatic patients > or = 12 years of age. Intal Study Group

STUDY OBJECTIVES

This multicenter, randomized, double-blind, placebo-controlled, parallel study compared the efficacy and safety of the hydrofluoroalkane (HFA) formulation of cromolyn sodium metered-dose inhaler (MDI) with the chlorofluorocarbon (CFC) formulation in asthmatic patients > or = 12 years old over a 12-week period.

DESIGN

Stable asthmatics using only currently marketed cromolyn sodium and as-needed inhaled beta2-agonists were randomly assigned to treatment with HFA cromolyn sodium, CFC cromolyn sodium, or placebo, administered as two inhalations (2 mg) qid for 12 weeks. Prior to randomization, all patients were required to meet minimum symptom and/or pulmonary function test criteria after discontinuation of cromolyn sodium. Efficacy was assessed by changes in daily symptom scores, albuterol use, peak expiratory flow, pulmonary function measurements, and overall opinions of effectiveness.

RESULTS

A total of 280 patients in 29 centers were randomly assigned to treatment with HFA cromolyn sodium (n = 94), CFC cromolyn sodium (n = 91), or placebo (n = 95). Patients treated with the HFA formulation of cromolyn sodium demonstrated a 28 to 33% improvement over placebo for all symptom scores (p < 0.05) and a 35% improvement over placebo in the use of albuterol MDI (p < 0.05). The patients' opinions of overall effectiveness favored HFA cromolyn sodium (p = 0.011) and CFC cromolyn sodium (p = 0.006) over placebo. The investigators' opinions indicated a statistically significant difference favoring CFC cromolyn sodium compared with both placebo (p < 0.001) and HFA cromolyn sodium (p = 0.042). No statistically significant differences existed among groups in the incidence of treatment-related adverse events.

CONCLUSION

The HFA formulation of cromolyn sodium MDI is a well-tolerated and effective treatment for asthma patients > or = 12 years old. The safety and efficacy profile of the HFA formulation is comparable to that of the CFC formulation.

Relationship between mite, cat, and dog allergens in reservoir dust and ambient air

BACKGROUND

Standardized methods to measure allergen exposure are essential to assess the relationship between exposure, sensitization, and asthma. Most studies have measured allergen levels in reservoir dust, although air samples may be more representative as a measure of inhaled allergen. The aim of this study was to define the relationship between mite, cat, and dog allergen content in the reservoir dust and the levels in the ambient air.

METHODS

Dust samples from the living-room floor (LF) and sofa (S) were collected in 127 homes: 62 without and 65 with pets (31 dogs, 34 cats). Air samples were taken in the same room, with a high-volume pump for 1 h (flow 60 l/min). Der p 1, Fel d 1, and Can f 1 were determined by mAb-based ELISA.

RESULTS

Airborne Der p 1 was below the detection limit (0.8 ng/m3) in all homes, with reservoir levels (GM and range) being 1.14 microg/g (0.2-66) and 1.15 microg/g (0.2-127) in LF and S, respectively. Airborne Can f 1 was detected in 40/62 homes without pets (range 0.6-12.4 ng/m3) and in all homes with dogs (range 0.5-99 ng/m3). In the multiple linear regression analysis, Can f 1 level in the LF was an independent correlate of the airborne Can f 1 (P=0.01, homes with dogs; P=0.04, homes without dogs). Fel d 1 was detected in the air in 16/62 homes without pets (range 0.16-1.8 ng/m3) and in all homes with cats (range 0.4-22.3 ng/m3). Fel d 1 level in the LF was an independent correlate of the airborne Fel d 1 in homes without cats (P=0.008), but airborne levels in homes with cats did not correlate with reservoir levels.

CONCLUSIONS

The aerodynamics of each allergen must be taken into account when assessing exposure: while levels in reservoir dust are the best available index for mite allergens, airborne levels might be more suitable for defining exposure to pets. If air samples are difficult to obtain, levels of Can f 1 and Fel d 1 in the LF samples should be used as a surrogate measure of personal exposure.

The effects of triamcinolone acetonide aqueous nasal spray on adrenocortical function in children with allergic rhinitis

BACKGROUND

Suppression of adrenocortical function, a risk associated with oral corticosteroids, is minimized with intranasal corticosteroids. Triamcinolone acetonide (TAA) aqueous nasal spray, at therapeutic doses, has no measurable effect on adrenocortical function in adults with allergic rhinitis.

OBJECTIVE

This double-blind, placebo-controlled study compared the effect of once-daily TAA aqueous nasal spray (220 or 440 microg) with placebo on adrenocortical function after 6 weeks of treatment in pediatric (children 6 to 12 years of age) patients with allergic rhinitis. The pharmacokinetic profile of TAA was examined after once-daily intranasal administration of TAA aqueous nasal spray 440 microg for 6 weeks.

METHODS

Eighty children received TAA aqueous nasal spray 220 microg or 440 microg or placebo for 6 weeks. Adrenocortical function was assessed by analyzing plasma cortisol levels before stimulation (0 hour) and at 30 and 60 minutes after a rapid 1-hour intravenous cosyntropin stimulation test performed before treatment and after 6 weeks of treatment. Samples for pharmacokinetic evaluation were collected from 19 patients at baseline (0 hour) and at 0.5, 1, 1.5, and 6 hours after the final dose of study medication.

RESULTS

After 6 weeks, no significant effects on adrenocortical function were observed at 30 or 60 minutes after cosyntropin stimulation with either dose of TAA aqueous nasal spray. TAA concentrations in plasma showed rapid elimination of the drug, with little or no accumulation.

CONCLUSIONS

TAA aqueous nasal spray (220 or 440 microg/day) has no measurable effect on adrenocortical function in pediatric patients with allergic rhinitis. Pharmacokinetic parameters after 440 microg/day of TAA aqueous nasal spray indicate a rapid decline of plasma drug levels, with little or no systemic accumulation of study drug.