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T Schäfer

Publications and source records attributed to T Schäfer.

At least 19 recordsLinked to original sources
PubMed2006

Meson supercurrent state in high-density QCD.

The ground state of three flavor quark matter at asymptotically large density is believed to be the color-flavor-locked (CFL) phase. At nonasymptotic density the effect of the nonzero strange quark mass cannot be neglected. If the strange quark mass exceeds m(s) approximately m(u)(1/3)delta(2/3), the CFL state becomes unstable toward the formation of a neutral kaon condensate. Recently, several authors discovered that for m(s) approximately (2deltap(F))(1/2) the CFL state contains gapless fermions, and that the gapless modes lead to an instability in current-current correlation functions. Using an effective theory of the CFL state, we demonstrate that this instability can be resolved by the formation of a meson supercurrent, analogous to Migdal's p-wave pion condensate. This state has a nonzero meson current that is canceled by a backflow of gapless fermions.

Journal Article↗
PubMed2006

[Results of a comparison: active versus passive reporting in cases of community acquired pneumonia. Results of the German Competence Network CAPNETZ].

INTRODUCTION: Since 2002, the German competence network CAPNETZ has been collecting data from inpatients and outpatients with community acquired pneumonia (CAP) at eight local clinical centres. Contrary to the literature reports, the proportion of outpatients in CAPNETZ averages out at 28 %. Therefore, this study determines whether an active reporting system can increase the number of cases reported in medical practices. METHOD: In ten medical practices in Lübeck, the passive reporting system was changed to an active reporting system consisting of a) a weekly announcement of CAP cases including negative reporting, b) a study nurse who was responsible for the reporting, c) additional payment, d) a telephone call after two weeks by absent announcements and e) incentives like benchmarking or additional information. The number of the reported cases between the active reporting period (2004) and the same period in the year before was recorded. RESULTS: The number of reported cases increased in eight of the ten medical practices. Overall 72 CAP cases were reported, 33 % more than in the period of passive reporting. The number of patients encompassed in CAPNETZ increased from 17 to 34. CONCLUSION: We did not find a comparable increase of CAP cases either in Lübeck overall (including inpatients) or in all the local clinical centres together. Thus, it is assumed that the increase of reported cases depends on the methodical effect.

Community Networks↗
PubMed2006

The course of eczema in children aged 5-7 years and its relation to atopy: differences between boys and girls.

BACKGROUND: The role of atopy in the pathophysiology of eczema is still under debate. The concept and analyses of the nonatopic and atopic subtypes of eczema have gained increasing interest in recent studies. The course of these subtypes and differences between boys and girls have not been investigated so far. OBJECTIVES: To examine the course of nonatopic and atopic eczema in preschool children from Germany with regard to sex. METHODS: Repeated cross-sectional studies were performed in 5-7-year-old preschool children from Germany between 1994 and 2000. Individuals with eczema were identified by a dermatological examination. In addition to a questionnaire, skin prick tests and analyses of serum IgE antibodies against seven and five environmental allergens, respectively, were performed. Atopy was defined by sensitization to at least one of five common aeroallergens (birch, grass and mugwort pollen, house dust mites, cat dander). In part of the study population investigations of spare time behaviour and skin function were carried out (including stratum corneum hydration and skin surface pH). RESULTS: A total of 2693 girls and 2783 boys underwent a full dermatological examination of the skin and determination of sensitization. Among the girls, 8.7% demonstrated eczema clinically at the day of investigation in contrast to 6.1% of the boys. In girls, early onset eczema (< 2 years of age) was strongly related to atopy at age 5-7 years [odds ratio (OR) 3.7; 95% confidence interval (CI) 2.7-5.1], whereas late-onset eczema (> or = 2 years of age) was not (OR 1.0; 95% CI 0.7-1.5). Boys were more often atopic at the age of 5-7 years than girls (28.3% vs. 20.6%), and early and late-onset eczema were related to atopy without such a difference (OR 2.8, 95% CI 2.0-4.0; OR 1.9, 95% CI 1.3-2.8, respectively). The excess of current eczema in 5-7-year-old girls compared with boys was related to the nonatopic type. The higher susceptibility of girls in that age group to develop eczema was reflected by the skin physiological examination: even girls without eczema had significantly higher skin surface pH and lower stratum corneum hydration than boys. Additionally, questionnaire data revealed that girls more often than boys predominantly played indoors, which was associated with more eczema. CONCLUSIONS: Atopy and eczema develop differently in boys and girls. Boys are more often atopic, whereas girls suffer significantly more often from eczema without relation to atopy. The nonatopic type of eczema in preschool girls is noticed predominantly after their second birthday. Genetic and lifestyle factors may contribute to this difference.

Age of Onset↗
PubMed2006

Melanoma risk in congenital melanocytic naevi: a systematic review.

BACKGROUND: The risk of malignant melanoma in congenital melanocytic naevi (CMN) is a matter of controversial and ongoing debate. OBJECTIVES: The purpose of this systematic review is to provide a careful and detailed summary of the published data, including several recently published studies. METHODS: Articles on CMN (n=1424) were retrieved from Medline, 1966-October 2005. Case reports and studies lacking relevant clinical information were excluded. Only systematic collections of cases were taken into consideration. Series with fewer than 20 patients or studies with a mean follow-up of <3 years were regarded as epidemiologically less significant. RESULTS: Fourteen articles were finally chosen for further analysis. The studies varied significantly with respect to study design (source of cases; retrospective vs. prospective analysis), age of patients, follow-up time, and naevus characteristics. The frequency of melanomas ranged between 0.05% and 10.7% and was significantly higher in smaller studies (P<0.0001). In a total of 6571 patients with CMN who were followed for a mean of 3.4-23.7 years, 46 patients (0.7%) developed 49 melanomas. The mean age at diagnosis of melanoma was 15.5 years (median 7). By comparison with age-adjusted data from the Surveillance, Epidemiology and End Results database, we calculated that patients with CMN carry an approximately 465-fold increased relative risk of developing melanoma during childhood and adolescence. Primary melanomas arose inside the naevi in 33 of 49 cases (67%). In seven cases (14%), metastatic melanoma with unknown primary was encountered; in four cases (8%) the melanoma developed at an extracutaneous site. The risk of developing melanoma and the rate of fatal courses were by far highest in CMN>or=40 cm in diameter. CONCLUSIONS: The overall risk of melanoma of 0.7% in all 14 studies was lower than expected. The higher incidence of melanomas in smaller studies indicates selection bias. The melanoma risk strongly depends on the size of CMN and is highest in those naevi traditionally designated as garment naevi. The median age of 7 years at diagnosis of melanoma points to a risk maximum in childhood and adolescence. Future studies on CMN should report: (i) diameter, percentage of body surface, and localization of the CMN; (ii) percentage of naevus area removed by excision or subject to dermabrasion or other superficial treatments; (iii) mean and median age at entry into the study; (iv) mean and median follow-up time; (v) details on each melanoma case; (vi) standardized morbidity ratio of melanoma; and (vii) percentage of neurocutaneous melanosis.

Adolescent↗
PubMed2006

Inverse association between periodontitis and respiratory allergies.

BACKGROUND: Periodontitis is an infection with systemic effects and a high prevalence among adults. In the aetiology of allergic diseases the hygiene hypothesis claims that infections in early infancy may protect against allergic diseases. OBJECTIVE: The aim of the present analyses was to investigate the independent relation between periodontitis and respiratory allergies such as hayfever, house dust mite (HDM) allergy and asthma. METHODS: From the Study of Health in Pomerania (SHIP) a total number of 2837 subjects aged 20 to 59 years were included in the analysis. In our study population 326, 111 and 114 subjects were classified as suffering from hayfever, HDM allergy or asthma, respectively. The attachment loss (AL) were measured. Periodontitis was defined according to the percentage of surfaces which exceeded 3 mm AL [healthy: 0-7.7%, mild: 7.8-28.6%, moderate: 28.7-63.9%, severe: >63.9%]. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression. RESULTS: After adjustment for confounding factors these analyses revealed inverse associations between periodontitis and hayfever as well as periodontitis and HDM allergy. For increasing AL, a trend of decreasing risk could be observed for hayfever (healthy: reference; mild AL: OR 0.87 [95%-CI 0.6-1.2]; moderate AL: OR 0.80 [95% CI 0.6-1.2]; server AL: OR 0.53 [95% CI 0.3-0.9]; P(trend)=0.01) and for HDM allergy (healthy: reference; mild AL: OR 0.80 [95% CI 0.5-1.3]; moderate AL: OR 0.64 [95% CI 0.3-1.2]; server AL: OR 0.39 [95% CI 0.2-0.9]; P(trend)=0.02). Furthermore, for asthma were observed a slightly inverse association in the full-adjusted model (healthy: reference; mild AL: OR 1.10 [95% CI 0.6-2.0]; moderate AL: OR 0.96 [95% CI 0.5-1.8]; server AL: OR 0.48 [95% CI 0.2-1.0]; P(trend)=0.11). CONCLUSION: There is an inverse association between periodontitis and respiratory allergies. Our results might support the hygiene hypothesis.

Adult↗
PubMed2006

EAACI/GA2LEN/EDF guideline: management of urticaria.

This guideline is the result of a consensus reached during a panel discussion at the second International Consensus Meeting on Urticara, Urticaria 2004, a joint initiative of the EAACI Dermatology Section and GA2LEN. Urticaria has a profound impact on the quality of life, and effective treatment is therefore required. The recommended first line treatment are nonsedating H1 antihistamines. They have proven to be effective in double-blind controlled studies, but dosages increased up to fourfold over the recommended doses may be necessary. However, for different urticaria subtypes and in view of individual variation in the course of the disease and response to treatment, additional or alternative therapies may be required. Immunosuppressive drugs like cyclosporin A and corticosteroids are not recommended for long-term treatment due to unavoidable severe adverse effects. This guideline was, in addition, accepted by the European Dermatology Forum (EDF) and formally approved by the European Union of Medical Specialists (UEMS).

Anti-Allergic Agents↗
PubMed2006

EAACI/GA2LEN/EDF guideline: definition, classification and diagnosis of urticaria.

This guideline is the result of a consensus reached during a panel discussion at the 2nd International Consensus Meeting on Urticaria, Urticaria 2004, a joint initiative of the European Academy of Allergology and Clinical Immunology Dermatology Section and the European Union (EU)-funded network of excellence, GA2LEN. It covers the definition and classification of urticaria, taking into account the recent progress in identifying causes, eliciting factors and pathomechanisms of this disease. We have outlined useful diagnostic approaches for different subtypes of urticaria. This guideline was, in addition, accepted by the European Dermatology Forum (EDF) and was formally approved by the European Union of Medical Specialists (UEMS).

Allergens↗
PubMed2006

Atopic eczema in children: another harmful sequel of divorce.

BACKGROUND: Different lifestyle factors seem to be associated with the risk for atopic diseases and some studies suggest that stress increases the risk of allergic sensitization, asthma and atopic eczema. Only few studies have investigated the association of early stressful life events and atopic eczema (AE) in children. SUBJECTS AND METHODS: Parents of participants of the ongoing LISA birth cohort study were asked to give information on life events, such as severe disease or death of a family member, unemployment, or divorce of the parents. Lifetime prevalence of AE and incidence after the assessment period for life events were compared. RESULTS: Prevalence of AE until the age of 4 years was 21.4%. Reported life events within the first 2 years were: severe disease (17.5%) or death (8.4%) of a family member, divorce/separation (3.4%), and unemployment (2.7%). Divorce/separation was associated with a significantly [odds ratio (OR) 3.59, 95% confidence interval (CI) 1.69-7.66] increased and disease with a significantly (OR 0.29, 95% CI 0.13-0.68) decreased incidence of AE for the subsequent 2 years of life. No effect was seen for unemployment. CONCLUSIONS: Divorce/separation of the parents and severe disease of a family member influence the risk of developing AE.

Child↗
PubMed2006

Swimming pool attendance and hay fever rates later in life.

BACKGROUND: Exposure to chlorination by-products through swimming pool attendance showed adverse health effects on children. The aim of our study was to assess whether pool attendance in childhood would be related to higher rates of allergic diseases in adulthood, with special regard to hay fever. METHODS: 2606 adults aged 35-74 years provided retrospectively collected information on swimming pool attendance and medical history, including data on atopic diseases. Information was assessed by a combination of a personal interview and a self-administered questionnaire. Logistic regression models were applied to study associations between hay fever and swimming pool attendance, adjusted for potentially relevant confounders, such as age, gender, region, education and smoking. RESULTS: Higher rates of hay fever could be seen when frequently exposed at school age (aOR: 1.74, 95% CI: 1.09-2.77), frequently exposed during the past 12 months (aOR: 1.32, 95% CI: 0.92-1.89) and ever exposed (aOR: 1.65, 95% CI: 0.98-2.78). Strongest associations were found for the youngest subjects and were dose-related to the extent of current and school-age pool attendance. CONCLUSIONS: Impaired integrity of the lung epithelial by exposure to chlorination by-products might facilitate a closer contact to allergens and therefore could result in higher rates of hay fever.

Adult↗
PubMed2005

[Risk factors for community acquired pneumonia (CAP). A systematic review].

BACKGROUND AND OBJECTIVE: Community acquired pneumonia (CAP) is the most frequent mortal infectious disease in the western industrial countries. So far no detailed information about incidence, pathogenetic agents, medical service and risk factors existed within Germany. This article reviews international studies, which identified risk factors for CAP. METHOD: The MEDLINE database search comprised 743 articles from 1966 to December 2003. Ten published studies analysing risk factors for CAP were included in this study. RESULTS: Age, gender, smoking and chronic lung diseases ranged among the leading risk factors. Other variables, like medication, dangerous substances, alcohol or sociodemographic factors have so far been insufficiently proved. CONCLUSION: Comparable data concerning CAP in Germany are currently inadequate. In order to improve the data situation, in 2002, the Community Acquired Pneumonia NETwork (CAPNET) was established. CAPNET assembles and soon intends to publish detailed information about incidence and risk factors of Community Acquired Pneumonia.

Adolescent↗
PubMed2005

[Prevention of atopic eczema. Evidence based guidelines].

With an estimated prevalence of 12% for preschool children and 3% for adults, atopic eczema is a serious public health problem. This disease severely jeopardizes quality of life and is associated with considerable costs. Since there is still no causal therapy, primary and secondary prevention are especially important. Here the evidence basis for recommendations on prevention of atopic eczema is discussed on the basis of the first evidence-based consensus guideline (S3) on allergy prevention. This recommends that babies should be breastfed exclusively for at least 4 months and exposure to passive smoking be avoided even during pregnancy; restriction of the maternal diet during pregnancy has no influence, though during breastfeeding it can lower the incidence of eczema among babies at risk. Thereby this measure should be balanced with potential consequences of malnutrition. There seems to be a positive correlation between keeping small rodents (rabbits, guinea pigs), and possibly cats, and the occurrence of atopic eczema, while keeping dogs has no effect or even a protective effect. Avoidance of an unfavorable indoor climate is probably also helpful in preventing eczema. There is no evidence to support deviating from the current recommendations of the standing committee for vaccination.

Clinical Trials as Topic↗
PubMed2005

[Allergies in adults].

Only few epidemiological studies have assessed allergic diseases in adults. In a follow-up study of the MONICA survey S3 (1994/95), which was performed 1997-1999, a total of 1,537 persons were interviewed and tested by skin prick and patch test. Furthermore data of the MONICA survey (RAST, cholesterol, food diaries) could be used. Within survey S4 (1999/2001) a total of 4,261 subjects were interviewed concerning their personal history of atopic diseases and the corresponding history of their partners. In survey S3 the prevalence of allergic sensitisation was 20.5 % for persons without formal graduation from school and 48.1 % for those with a university degree. 20.8 % reported a hypersensitivity to food and about one quarter exhibited a positive reaction in skin prick test. Atopic eczema and hay fever increased over quartiles of HDL cholesterol. Similar, allergic sensitisation (RAST) increased over quartiles of uptake of unsaturated fatty acids in men. 40 % of those who were patch tested exhibited a positive reaction, with perfume mix, nickel, thimerosal and balsam of Peru being the most prominent allergens. Inhabitants of the City of Augsburg were sensitised more often (34.0 % overall, 23.9 % pollen) than inhabitants of villages with (29.4 %, 17.0 %). Full time farmers were sensitised less frequently (22.0 %, 8.4 %). In survey S4 the lifetime prevalence of atopic diseases diagnosed by doctors was 5.1 % for atopic eczema, 6.1 % for asthma and 13.7 % for hay fever. Subjects who lived together with a partner who suffered from hay fever were affected in 19.6 % whereas 13.1 % had hay fever when the partner was not affected. Future studies will offer an unique opportunity to analyse the incidence and remission of manifestations of atopy in adults.

Adult↗
PubMed2005

Association of CARD15 polymorphisms with atopy-related traits in a population-based cohort of Caucasian adults.

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.

Alleles↗
PubMed2005

Effect of environmental and physiological factors on the antibacterial activity of Curvularia haloperoxidase system against Escherichia coli.

AIMS: The aim of this study was to investigate the influence of environmental and physiological factors on the susceptibility of Escherichia coli to the Curvularia haloperoxidase system. METHODS AND RESULTS: The Curvularia haloperoxidase system is a novel enzyme system that produces reactive oxygen species which have an antimicrobial effect. Escherichia coli MG1655 was exposed to the Curvularia haloperoxidase system under different temperatures and NaCl concentrations and after exposure to different stress factors. Temperature clearly affected enzymatic activity with increasing antibacterial effect at increasing temperature. The presence of NaCl interfered with the enzyme system and in the presence of 1% NaCl, no antibacterial effect could be observed at pH 7. Cells grown at pH 8.0 were in one experiment more resistant than cells grown at pH 6.5, whereas cells grown in the presence of 2% NaCl were more susceptible to the Curvularia haloperoxidase system. CONCLUSIONS: Environmental and physiological factors can affect the antibacterial activity of the Curvularia haloperoxidase system. SIGNIFICANCE AND IMPACT OF THE STUDY: The study demonstrates a systematic approach in assessing the effect of environmental and physiological factors on microbial susceptibility to biocides. Such information is crucial for prediction of application as well as potential side-effects.

Disinfectants↗
PubMed2005

Worm infestation and the negative association with eczema (atopic/nonatopic) and allergic sensitization.

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%, OR(adj): 0.45, 95% CI: 0.33-0.60). The finding was confirmed by the corresponding matched case-control analysis (OR(adj): 0.57, 95% CI: 0.41-0.79). Atopic eczema was affected more by a prior worm infestation (OR(adj): 0.31, 95% CI: 0.18-0.56) than the nonatopic eczema (OR(adj): 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%, OR(adj): 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.

Case-Control Studies↗
PubMed2005

Association study of mast cell chymase polymorphisms with atopy.

BACKGROUND: Atopic disorders are the result of complex interactions between genetic and environmental factors. Associations analyses between the promoter polymorphism rs1800875 in the mast cell chymase gene (CMA1) and atopy-related phenotypes have yielded inconsistent results. METHODS: We sequenced the CMA1 locus in 24 unrelated healthy individuals with serum IgE levels <50% percentile and 24 individuals with atopic eczema and serum IgE levels >90% percentile. Seven CMA1 single nucleotide polymorphisms (SNPs) were evaluated for evidence of associations with atopic phenotypes within a large population of German adults (n = 1875). Subjects were phenotyped by standardized questionnaires and interviews, skin prick testing and serum IgE measurements. Genotyping was performed using MALDI-TOF MS (Matrix-Assisted Laser Desorption Ionization-Time of Flight mass spectrometry). RESULTS: Promoter polymorphism rs1800875 was significantly associated with atopic eczema. No associations between any other single SNP and atopic phenotypes could be detected. Haplotype reconstruction revealed four of 128 possible haplotypes reaching estimated frequencies of 3% or more. Two of these haplotypes showed a borderline-significant association with atopic eczema, which did not remain significant after correction for multiple testing. CONCLUSIONS: Results confirm previous observations of a significant association between the CMA1 promoter polymorphism rs1800875 and atopic eczema, but not with serum IgE levels, and support the hypothesis that CMA1 serves as candidate gene for atopic eczema.

Chymases↗
PubMed2004

Cluster analysis of soft X-ray spectromicroscopy data.

Soft X-ray spectromicroscopy provides spectral data on the chemical speciation of light elements at sub-100 nm spatial resolution. When all chemical species in a specimen are known and separately characterized, existing approaches can be used to measure the concentration of each component at each pixel. In other cases (such as often occur in biology or environmental science), some spectral signatures may not be known in advance so other approaches must be used. We describe here an approach that uses principal component analysis to orthogonalize and noise-filter spectromicroscopy data. We then use cluster analysis (a form of unsupervised pattern matching) to classify pixels according to spectral similarity, to extract representative, cluster-averaged spectra with good signal-to-noise ratio, and to obtain gradations of concentration of these representative spectra at each pixel. The method is illustrated with a simulated data set of organic compounds, and a mixture of lutetium in hematite used to understand colloidal transport properties of radionuclides.

Cluster Analysis↗