Robert Siebers

Supplementation with Lactobacillus rhamnosus or Bifidobacterium lactis probiotics in pregnancy increases cord blood interferon‐γ and breast milk transforming growth factor‐β and immunoglobin A detection

Background This study explored the effects of maternal probiotic supplementation on immune markers in cord blood (CB) and breast milk.

Asthma and allergic symptoms in relation to house dust endotoxin: Phase Two of the International Study on Asthma and Allergies in Childhood (ISAAC II)

Background Several studies have consistently reported inverse associations between exposure to endotoxin in house dust and atopy. With regard to the association between house dust endotoxin and asthma, the results are inconsistent.

House dust mite allergen in pillows.

For many years asthmatic patients have been told to avoid using feather filled pillows on their beds, although there is no evidence to support this practice. Strachan and Careys case-control study is the first to have directly challenged this assumption.1 This study showed that, after exclusion of asthmatic subjects whose bedding had been changed because of their disease, pillows with synthetic fillings were a risk factor for severe asthma. In the light of this finding, we have compared pillows with synthetic and feather fillings for their content of Der p I, the major allergen of the house dust mite Dermatophagoides pteronyssinus. In December 1995 we took dust samples from nine pairs of pillows and analysed them for Der p I. Each pair consisted of one feather filled pillow and one …

Determinants of house dust mite allergen in homes in Wellington, New Zealand

Objectives To measure levels of the major Dermatophagoides pteronyssinus allergen (Der p 1) in homes in Wellington, New Zealand, and to examine factors which affect these levels.

Early supplementation with Lactobacillus rhamnosus HN001 reduces eczema prevalence to 6 years: does it also reduce atopic sensitization?

The role of probiotics in prevention of allergic disease is still not clear; efficacy may depend on the timing, dose, duration, and specific probiotic used. Using a double‐blind randomized placebo‐controlled trial (Australian New Zealand Clinical Trials Registry: ACTRN12607000518460), we have shown that in a high‐risk birth cohort, maternal supplementation from 35 weeks gestation until 6 months if breastfeeding and infant supplementation from birth until 2 years with Lactobacillus rhamnosus HN001 (HN001) (6 × 109 cfu/day) halved the cumulative prevalence of eczema at 2 and 4 years. Bifidobacterium animalis subsp lactis HN019 (HN019) (9 × 109 cfu/day) had no significant effect.

Dampness and moulds in relation to respiratory and allergic symptoms in children: results from Phase Two of the International Study of Asthma and Allergies in Childhood (ISAAC Phase Two)

Many studies report that damp housing conditions are associated with respiratory symptoms. Less is known about mechanisms and possible effect modifiers. Studies of dampness in relation to allergic sensitization and eczema are scarce.

House dust mite allergen levels in public places in New Zealand

BACKGROUND House dust mite allergens are a risk factor for asthma in New Zealand, and levels in domestic dwellings have been found to be high compared with levels in most other countries. Studies in other countries have demonstrated lower levels of Dermatophagoides pteronyssinus allergens in public places compared with levels in domestic dwellings. OBJECTIVES The purpose of this study was to measure reservoir Der p 1 levels in public places in New Zealand and to examine determinants of these levels. METHODS Reservoir dust was obtained in the two centers (Christchurch and Wellington) from hotels, hospitals, rest homes, churches, primary schools, childcare centers, cinemas, bank head offices, and airplanes; samples were also obtained from ski lodges. Single measurements of temperature and relative humidity were taken with thermohygrometers and an average humidity over 2 weeks was estimated with use of waxed wooden sticks. Information was collected on building construction, type of heating, and frequency of cleaning. Der p 1 levels (micrograms per gram of fine dust) for floor (n = 202), bed (n = 65), and seat (n = 24) samples in public places were expressed as geometric means (95% confidence intervals). RESULTS Der p 1 levels in public places were significantly lower than domestic levels in both Wellington and Christchurch. Both floor and bed levels were higher in hotels than in other public places. After controlling for potential confounders, floor Der p 1 levels were higher with carpeted floors (p < 0.0001) and lower with recent cleaning (p = 0.02) and bed Der p 1 levels were higher with timber wall construction (p = 0.03). Other building, heating, or cleaning characteristics did not show significant association with allergen levels. CONCLUSION Der p 1 levels were much lower in public places than in domestic dwellings with floor levels primarily affected by floor covering.

Indoor environment, atopy and the risk of asthma in children in New Zealand

The objective of this study was to examine the relationship between the indoor environment, atopy and asthma in 7–9‐year‐old children. Cases and controls were randomly selected from children who participated in the International Study of Asthma and Allergies in Childhood (ISAAC) in Wellington, New Zealand. Cases were children with a previous diagnosis of asthma and current medication use (n = 233) and controls were children with no history of wheezing and no diagnosis of asthma (n = 241). Information was recorded about the indoor environment during the first year of life and currently. Dust was sampled from floors and beds and Der p 1 and Fel d 1 measured using enzyme‐linked immunosorbent assays. Skin‐prick tests were performed with eight common allergens. Sensitization to Dermatophagoides farinae (OR = 3.19; 95% CI 1.74–5.84), Dermatophagoides pteronyssinus (OR = 2.06; 95% CI 1.16–3.65) and cat (OR = 3.89; 95% CI 1.06–14.30) were independently associated with current asthma. The use of a sheepskin in the first year of life (OR = 1.91; 95% CI 1.11–3.33) was also independently associated with current asthma but current Der p 1 levels showed no association with current asthma. Exposures in early life may be more important than current exposures in determining asthma at age 7–9 years. Prospective studies are needed in New Zealand to determine the relative importance of early life exposures to Der p 1 and other risk factors for asthma.

A pilot study of the effect of mechanical ventilation and heat exchange on house-dust mites and Der p 1 in New Zealand homes

We have examined the effect of reducing relative humidity (RH), with inbuilt mechanical ventilation and heat‐exchange (MVHE) units, on house‐dust‐ mite (HDM) counts and allergen levels, in a pilot study of 10 Wellington dwellings. Recent international prevalence studies in adults and children have confirmed a high prevalence of asthma in New Zealand, Sensitivity to HDM is common among the general population, and HDM is the major allergen associated with asthma. Recent studies of allergen levels have confirmed high concentrations of Der p 1 in the domestic environment. While humidity was significantly reduced in those dwellings fitted with ventilation units, no systematic effect on mites or Der p 1 was observed during the study period. When the reductions in humidity were examined in the context of the time spent below the critical equilibrium humidity (CEH), the intervention led to RH values below the CEH for only 39% of the total of 24‐h periods for which measurements were made. Reducing RH by means of MVHE in New Zealand domestic dwellings does not lower humidity sufficiently, or long enough, to have any measurable effect on HDM populations.

The pulmonary and extrapulmonary effects of inhaled β‐agonists in patients with asthma

The cardiovascular, respiratory, and hypokalemic effects of repeated inhalation of fenoterol, albuterol, and isoproterenol were compared in 12 subjects with stable asthma according to a double‐blind, crossover design. Ipratropium bromide served as a control providing bronchodilatation without extrapulmonary effects. Subjecs inhaled the β‐agonists on an equal‐weight basis (400 µg) at 0, 30, 40, and 45 minutes. Measurements of heart rate, blood pressure, total electromechanical systole (measure of inotropic activity), preejection period, QTc interval, plasma potassium levels, and forced expiratory volume in 1 second were made 5 minutes after each dose and again at 60 and 75 minutes. There were no differences in the bronchodilating effect between the β‐agonists. However, both fenoterol and isoproterenol resulted in greater positive inotropic stimulation than did albuterol, and fenoterol caused a greater fall in plasma potassium levels than did the other β‐agonists.