Biomedical subjects

Randolf Brehler

Publications and source records attributed to Randolf Brehler.

4 recordsLinked to original sources

PubMed2006

Functional characterization and expression analysis of the proteinase-activated receptor-2 in human cutaneous mast cells.

Proteinase-activated receptor-2 (PAR2) belongs to a new G protein-coupled receptor subfamily activated by serine proteinases. PAR2 has been demonstrated to play a role during inflammation and immune response in different tissues including the skin. We examined whether PAR2 is functionally expressed by cutaneous human primary skin mast cells (HPMC) and the human mast cell line 1 (HMC-1). Reverse transcription-polymerase chain reaction and FACS analysis show expression of PAR2 both at the RNA and protein level. HPMCs and HMC-1 also express PAR1, PAR3, and PAR4. Ca-mobilization studies demonstrate functional PAR2 expressed by human skin mast cells, as shown by natural and synthetic PAR2 agonists. PAR2 agonists induced histamine release from HPMC indicating a role of PAR2 in regulating inflammatory and immune responses by skin mast cells. Double-immunofluorescence staining reveals colocalization of PAR2 with tryptase in the majority of human skin mast cells. In conclusion, trypsin and tryptase as well as specific agonists for PAR2 were able to induce Ca2+ mobilization in HPMCs, and agonists of PAR2 induce the release of histamine from these cells. Thus, PAR2 may be an important regulator of skin mast cell function during cutaneous inflammation and hypersensitivity.

Calcium↗

PubMed2003

Positive effects of a fresh air filtration system on hay fever symptoms.

BACKGROUND: Avoidance of allergen exposure is the basic preventive measure in reducing symptoms of immediate-type allergies. As room air cleaners were found to have no benefic effect on general health, their use has not been recommended. The purpose of this study was to evaluate the effect of a fresh air filtration system installed in the bedrooms of non-air-conditioned homes on hay fever symptoms. METHODS: In a placebo-controlled, double-blind, two-period, crossover study, we investigated the effectiveness of a fresh air filtration system installed in the bedrooms of volunteers suffering from hay fever. RESULTS: Volunteers only suffering from pollinosis reported an improvement of their allergy symptoms. We observed a significant decrease in nighttime hay fever symptoms and an increase in morning peak expiratory flow rates (PEFR). No effects were recognized in volunteers who additionally had perennial allergy. CONCLUSION: Based upon these results, the installation of fresh air filtration systems in bedrooms should be recommended for patients suffering from hay fever.

Adult↗

PubMed2002

Latex allergy.

The prevalence of IgE mediated natural latex rubber allergy is estimated to be < 1% in the general population, < 17% in medical personnel and approximately 0% in children with spina bifida. We review the definition, diagnosis, prevention, and treatment of NLR allergy.

Diagnosis, Differential↗

PubMed2002

Allergenicity of natural rubber latex gloves.

The concentrations of proteins, allergens and rubber chemicals are essential parameters of the allergenicity of NRL gloves. To date, a standardized method has been given only for analysis of the protein concentration (DIN EN 455-3), and not for the concentrations of allergens and rubber chemicals. In the present study, we investigated 11 brands of surgical gloves currently available on the German market. Additionally 1 glove, not subjected to final leaching procedures, was added for comparison purposes. Protein concentrations were analysed by different methods in different laboratories. Allergen concentrations were assayed by prick tests in NRL-allergic volunteers and by RAST inhibition methods. Rubber chemicals were analysed by HPTLC and GC. The protein concentrations analysed by the Lowry method in the 2 laboratories gave concordant results, but the correlations between protein and allergen concentrations were low. The protein concentration analysed by HPLC correlated with the allergen concentration, and gave better information on the allergenicity of the gloves. The development of standardized methods for allergen analysis in the assessment routine is necessary, due to significant discrepancy between protein and allergen levels of some gloves. Thiurams were not found in any of the gloves, though carbamates were present in all gloves tested. Our data indicate that washing procedures have little or no effect on the concentration of rubber chemicals.

Adult↗