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Notes: Ferromagnetism persisting above 375 K and anisotropic ferromagnetic resonance (FMR) spectra have been detected for the first time in Si co-implanted with Mn and As and annealed under appropriate conditions. For comparison, semi-insulating GaAs samples have been implanted with the same ions and subsequently annealed. They also exhibit ferromagnetism with a Curie temperature well in excess of 375 K. High-resolution transmission electron microscopy (TEM) performed on the samples with the best magnetic characteristics has shown the presence ofnanoclusters due to the segregation of the implanted species in both Si and GaAs. The angular dependence of the FMR spectra also reveals the existence of magnetic clusters with the hard magnetization axis aligned along the four equivalent 〈111〉 crystal axes. The spectra are very similar in Si and GaAs, indicating that the clusters in both materials probably consist of hexagonal MnAs

Notes: Background Influences of microbial pathogens are crucial for the maturation of the immune system. Caspase-recruitment domain containing protein 15 (CARD15) is a cytosolic receptor involved in bacterial recognition by antigen-presenting cells. CARD15 polymorphisms have been associated with Crohn's disease. Recently, associations with atopic phenotypes have been reported in children.Objective Within a large population of German adults (n=1875), we evaluated eight CARD15 polymorphisms for associations with atopic phenotypes.Methods Subjects were phenotyped by standardized questionnaires and interviews as well as total and allergen-specific IgE measurements. Genotyping was performed using matrix-assisted laser desorption ionization – time of flight mass spectrometry. Haplotypes were estimated using the SAS/Genetics module.Results Subjects with a T allele at rs1077861 had a decreased risk of developing asthma (odds ratio OR=0.648, P=0.013), whereas the presence of an A allele at rs3135500 was significantly associated with an increased risk (OR=1.374, P=0.023). In addition, a CARD15 haplotype revealed to be protective against the development of asthma (OR=0.326, P=0.003). Subjects with an A allele at position rs5743266 or a T allele at rs2066842 had a significantly decreased risk of developing allergic rhinoconjunctivitis with ORs of 0.820 (P=0.049) and 0.801 (P=0.025). Polymorphism rs2066845 showed a significant association with increased total serum IgE (OR=2.155, P=0.006).Conclusion Genetic variants of CARD15 that might result in inappropriate immunomodulation are not only associated with autoimmune diseases but also with atopic disorders.

Notes: Background:  Worm infestations may play a role in preventing allergies. There is a lack of epidemiological information from Western countries on the association between worm infestation and eczema.Objective:  To investigate the association between worm infestation and eczema in a proper temporal sequence and under consideration of allergic sensitization.Methods:  Two surveys were performed in East German school children. Questionnaire data included the history of eczema and worm infestation and their time of onset. Specific IgE antibodies to five common aeroallergens were measured and used to define nonatopic and atopic eczema. Logistic regression analyses were performed to control for relevant confounders (age, sex, parental school education and history of allergies). In order to confirm the findings a corresponding conditional regression analysis was applied on cases and controls matched by age and sex.Results:  A total of 4169 children participated (response 75 and 76%) who were, on average, 9.2 years old (47% girls). Overall 17.0% reported a prior worm infestation (Ascaris 44%, Oxyuris 33%) and 18.1% had a history of eczema. Eczema occurred significantly less frequent in children who had a worm infestation (prior to the onset of eczema) compared with children without such a history (8.1%vs 16.5%, ORadj: 0.45, 95% CI: 0.33–0.60). The finding was confirmed by the corresponding matched case–control analysis (ORadj: 0.57, 95% CI: 0.41–0.79). Atopic eczema was affected more by a prior worm infestation (ORadj: 0.31, 95% CI: 0.18–0.56) than the nonatopic eczema (ORadj: 0.58, 95% CI: 0.40–0.84). A total of 29.1% exhibited specific IgE antibodies to at least one aeroallergen. Sensitized children gave significantly less frequent a history of worm infestation (14.2%vs 18.3%, ORadj: 0.74, 95% CI: 0.60–0.92). Stratified analysis revealed that this effect most pronounced for a sensitization to house dust mite.Conclusions:  A worm infestation is associated with a reduced frequency of subsequent eczema, especially the atopic type. Furthermore allergic sensitization, especially to house dust mite, and worm infestation are negatively associated. The data support the concept that a lack of immune-stimulation by parasitic infections contributes to the development of allergies.

Notes: Background:  Moisture is vitally important for house dust mites and they cannot survive in cold or hot-dry climates.Aims of the study:  To investigate the influence of two extraordinarily cold and dry winters in 1995/1996 and 1996/1997 on house dust mite levels in German homes.Methods:  Dust samples were collected between June 1995 and December 2001 on the mattresses of 655 adults and 454 schoolchildren living in five different areas of Germany. We compared house dust mite allergen Dermatophagoides pteronyssinus (Der p 1) levels before and during the winters of 1995/1996 and 1996/1997 with levels after these winters.Results:  D. pteronyssinus (Der p 1) levels in samples taken after the cold winters of 1995/1996 and 1996/1997 were approximately two times lower than Der p 1 levels in dust samples collected before or during these respective winters (Geometric means: Erfurt 89 vs 33 ng/g; Hamburg 333 vs 219 ng/g; Bitterfeld, Hettstedt, and Zerbst 296 vs 180 ng/g). Except for Hamburg, the decrease in Der p 1 levels was statistically significant. D. pteronyssinus levels measured in dust samples collected in 2001 (i.e. 3 years after the two cold winters) show a statistically non-significant increase (Geometric means: Erfurt 33 vs 39 ng/g; Hamburg 219 vs 317 ng/g), suggesting that it may take a long time for mite allergen levels to increase again after a sudden decrease.Conclusion:  We conclude that Der p 1 levels in German mattress dust samples have been approximately reduced by a factor of three to four by the two consecutive cold winters of 1995/1996 and 1996/1997.