Domestic cat allergen and allergic sensitisation in young children

Studies have presented conflicting associations between cat allergen exposure and sensitisation and atopic disease. We therefore investigated the association between the observed domestic cat allergen level and cat sensitisation in young children in four study populations from three European countries. We recruited children from a nested case-control study, which is composed of four ongoing birth cohorts conducted in three European countries. Children at 2-4 years of age in the four cohorts who were sensitised to cat allergens (n=106) were compared with 554 non-sensitised children (controls). House dust samples were collected when the children were 5 to 7 years old, and cat allergen levels were measured in ng/g dust and ng/m(2) surface area. In the German study population we found a positive association between domestic cat allergen in house dust and cat sensitisation (OR (CI)=3.01 (1.16, 7.99)) while in the Swedish study population, we found a negative association (OR (CI)=0.41 (0.16, 0.98)). No association was found in the Dutch study population (OR (CI)=0.83 (0.22, 2.93)). Looking into the family history of cat keeping, we found the lowest prevalence of cat sensitisation in children who were cat owners at the age of blood sampling (11%) and the highest prevalence was found in those who have had a cat but not anymore, at the age of blood sampling (41%). The mixed results may be explained by differences in age and avoidance patterns.     

Respiratory symptoms in relation to indoor exposure to mite and cat allergens and endotoxins. Indoor Factors and Genetics in Asthma (INGA) Study Group.

The authors investigated the relationship between respiratory symptoms in adults and exposure to mite and cat allergens, the role of endotoxins in house dust, the effects of mixtures of several allergens, and interactions between allergen exposure and allergic sensitization. Within a nested case-control study, 405 subjects aged 25-50 yrs from two German cities answered a standardized questionnaire. Allergen-specific immunoglobulin-E was measured. Dust samples were taken from the subjects' homes to determine exposure to mite (Dermatophagoides pteronyssinus antigen 1 Der p 1) and (D. farinae antigen 1 Der f l) and cat (cat antigen d1 Fel d 1) allergen and endotoxin content in settled house dust. Exposure to Der f 1 and Der p 1 plus Der f 1 >10 microg x g(-1) of mattress dust, respectively, increased the risk of wheeze and breathlessness (odds ratios (OR): 4.04, 95% confidence interval (CI): 1.53-10.64, OR: 2.78, 95% CI: 1.06-7.28). Fel d 1 >8 microg x g(-1) was positively associated with cough at night (OR: 2.74, 95%, CI: 1.22-.17), noteworthy also in the nonsensitized subjects. Subjects exposed to elevated concentrations of more than one allergen had an up to seven-fold increase in the risk of respiratory symptoms, compared to nonexposed subjects. Sensitized subjects exposed to elevated concentrations of Der f 1 or Fel d 1 were found to have the highest risk of asthma attacks and respiratory symptoms. No statistically significant association was found between exposure to endotoxins and respiratory health. Indoor exposure to Dermatophagoides farinae antigen 1 and cat antigen d1 is a risk factor for respiratory symptoms in adults, and for cat antigen d 1 even in nonsensitized subjects. The risk is increased if subjects are exposed to a mixture of allergens or if they are sensitized in addition to high exposure.     

Fine particles, a major threat to children

BACKGROUND: There is a growing body of evidence for serious health consequences of exposure to ambient air pollution. The general question of who is susceptible is one of the most important gaps in current knowledge regarding particulate matter (PM)-related health effects. Who is susceptible depends on the specific health endpoint being evaluated and the level and length of exposure. Here, we restrict the review on the impact of fine particle exposure on children's health to the following outcomes: infant death, lung function, respiratory symptoms and reproductive outcomes. METHODS: This is a strategic review of children's susceptibility to ambient fine particles and characteristics of infant and children which underlie their increased susceptibility to PM. RESULTS: Ambient fine PM is associated with intra-uterine growth retardation, infant mortality; it is associated with impaired lung function and increased respiratory symptoms, particularly in asthmatics. Concerning infant mortality, exposure to PM is strongly and consistently associated with postneonatal respiratory mortality and less consistently with sudden infant death syndrome. Although most of the studies reported adverse effects for this health outcome, the evidence is weaker than for infant death. Exposure to fine PM has been associated with impaired lung function and lung function growth. Most of the studies reported increased prevalence of symptom with increased exposure to fine PM. CONCLUSION: Fine PM is a major threat to children, because of their higher exposure to PM compared to adults, the immature state of the lung in childhood and also of the immune function at birth. The first months of life might be a period of particular sensitivity. Although the mechanisms of air pollution effects have not yet been completely understood, pregnant women, infants and children need specific protection against exposure to fine particles.     

Pulmonary and systemic effects of short-term inhalation exposure to ultrafine carbon black particles

While environmental particles are associated with mortality and morbidity related to pulmonary and cardiovascular (CV) disease, the mechanisms involved in CV health effects are not known. Changes in systemic clotting factors have been associated with pulmonary inflammation. We hypothesized that inhaled ultrafine particles result in an inflammatory response which may stimulate systemic clotting factor release. Adult male Wistar rats were exposed to either fine or ultrafine carbon black (CB) for 7 h. The attained total suspended particle concentrations were 1.66 mg/m³ for ultrafine CB and 1.40 mg/m³ for fine CB. Particle concentration of ultrafine particles was more than 10 times greater than that of fine particles and the count median aerodynamic diameter averaged 114 nm for the ultrafine and 268 nm for the fine carbon particles. Data were collected immediately, 16 and 48 h following exposure. Only ultrafine CB caused an increase in total bronchoalveolar lavage (BAL) leukocytes, whereas both fine (2-fold) and ultrafine (4-fold) carbon particles caused an increase in BAL neutrophils at 16 h postexposure. Exposure to the ultrafine, but not fine, carbon was also associated with significant increases in the total numbers of blood leukocytes. Plasma fibrinogen, factor VII and von Willebrand factor (vWF) were unaffected by particle treatments as was plasma Trolox equivalent antioxidant status (TEAC). Macrophage inflammatory protein-2 mRNA was significantly increased in BAL cells 48 h following exposure to ultrafine CB. The data show that there is a small but consistent significant proinflammatory effect of this exposure to ultrafine particles that is greater than the effect of the same exposure to fine CB.     

Multiple regions of alpha-synuclein are associated with Parkinson's disease

alpha-Synuclein is considered to play an important role in the pathogenesis of both the rare familial and the common sporadic forms of Parkinson's disease. Previous reports primarily have tested the association of alpha-synuclein promoter polymorphisms with idiopathic Parkinson's disease, but results are controversial. We first characterized the linkage disequilibrium structure of the alpha-synuclein gene region with a dense set of 56 genetic markers and subsequently performed two independent case-control association analyses using tagging markers. We could distinguish two large linkage disequilibrium blocks spanning the alpha-synuclein gene. Several markers within the 3'-block around exons 5 and 6 showed strong association with Parkinson's disease (p = 0.00009). Effects of the associated variants might be mediated by regulatory elements in this highly conserved region or by a frequency shift in a previously described splice variant lacking exon 5. A direct association with promoter polymorphisms could not be replicated in our sample set. A second set of markers in the 5'-block of the gene were also significantly associated with Parkinson's disease, when young patients and female subjects were analyzed separately. These findings indicate locus heterogeneity for the pathogenesis of Parkinson's disease in different genetic or physiological environments, related to sex and age.     

Practical evaluation of standard-based low-cost video conferencing in telemedicine and epidemiological applications.

The results of the evaluation of use of low-cost video conferencing systems (VCSs) in telemedicine is presented. Applications sharing, a new feature of these systems, recently has allowed high-quality computer-supported collaborative work (CSCW). The video conferencing (VCing) equipment used was Intel ProShare 200 v2.0a. It is representative of other low-cost VCSs. The areas of application are epidemiology and telemedicine (orthopaedics and radiology). Potential end users filled out 58 evaluation questionnaires concerning user profiles, contents and benefits of the sessions, organizational aspects, user friendliness, user acceptance, cost effectiveness, technical and multipoint related aspects. Although the end users had a lot of computer experience, their knowledge in VCSs was rather limited. The users assessed the system capable of being integrated into routine work, despite a high organizational impact. The VCS is user friendly, application sharing being used in almost every session. Audio quality was not always sufficient. The remote video was sufficient, as was the quality of medical images such as CT, MRI or X-ray. The user acceptance of the system was high. Multipoint sessions require a structured protocol to be effective. Some technical problems with MCUs (Multipoint Control Units) occurred. The use of low-cost standard VCSs in telemedicine is advisable and is a good substitute for real meetings.