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V Junghans

Publications and source records attributed to V Junghans.

6 recordsLinked to original sources

Results of a surveillance programme for patients at high risk of malignant melanoma using digital and conventional dermoscopy.

Patients with a high number of atypical naevi and a personal and/or family history of melanoma are at high risk of malignant melanoma. The objective of this study was to design a special documentation and surveillance programme using epiluminescence microscopy (ELM) and digital epiluminescence microscopy (DELM) to improve the surveillance of these patients. High-risk patients (n=212) were categorized by the number and phenotype of their naevi and their personal and family history of melanoma. Then patients were screened by the unaided eye, conventional photography, ELM and, in selected cases of atypia, DELM. Median follow-up was 18 months, and 2939 pigmented lesions were followed by DELM. Examination on the first visit identified 17 cutaneous melanomas. During the following observation period, another 17 melanomas were identified. Fifteen of these follow-up melanomas were exclusively identified based upon DELM. In these cases, subtle lesional changes occurred over time, and ELM diagnostic algorithms for differentiating benign melanocytic lesions from melanoma did not score a suspicion of melanoma. All melanomas, either pre-existing or developing during follow-up, were identified in an early, curable phase of tumour growth. We conclude that DELM follow-up for patients at high risk allows the early detection of melanomas that have not yet acquired melanoma-typical ELM features.

Adult↗

Inverse correlation of domestic exposure to Dermatophagoides pteronyssinus antigen patch test reactivity in patients with atopic dermatitis.

BACKGROUND: In recent years considerable interest in the pathogenetic role of aeroallergens exacerbating atopic dermatitis (AD) has emerged. The 'atopy patch test' with aeroallergens was introduced by Platts-Mills et al. as an experimental model and as a diagnostic tool. However, its relevance for the clinical manifestation of AD is still not clear. OBJECTIVE: We asked whether there is a relationship between the individual antigen exposure to the major allergen of Dermatophagoides pteronyssinus (Der p 1) and the immunological markers of sensitization to Der p 1 or the clinical severity of AD. METHODS: We investigated 92 patients with moderate to severe AD. For clinical evaluation the SCORAD severity score was used. Patch tests were performed with purified Der p 1. Specific IgE was measured by a commercial assay. Der p 1 exposure was quantified in a sample of the patient's mattress dust by using a commercial ELISA. RESULTS: No correlation between SCORAD, Der p 1 exposure and RAST could be established. However, there was an unexpected significant inverse correlation between the quantity of mite antigen in the mattress dust and patch test reactivity. Patients with a high antigen load (> 25 microg/g) mostly had a negative patch test. Also, when Der p 1 was correlated to the mattress area (m2) in this group all patch tests were negative. A possible explanation could be that continuous exposure of the skin to house dust mite allergen Der p 1 may induce a down-regulation of the skin immune system of patients with AD. CONCLUSION: Although the mechanism of this phenomenon is presently unknown, our study shows that a positive allergen patch test alone should not be an indication to undertake allergen exclusion measures in AD patients.

Adolescent↗

Epidermal cytokines IL-1beta, TNF-alpha, and IL-12 in patients with atopic dermatitis: response to application of house dust mite antigens.

Epidermal cytokines such as interleukin (IL)-1beta, tumor necrosis factor-alpha, and IL-12 have been described to play a crucial role in the induction and elicitation phase of allergic contact dermatitis upon exposure to haptens. In this study we asked whether these cytokines may also play a role in the epidermis of patients with atopic dermatitis after the application of house dust mite antigens (HDM) to their skin. Epidermal samples were collected by scraping healthy appearing skin of atopic patients and healthy individuals 8 h after the application of an extract of HDM. Sodium lauryl sulfate and saline served as controls. Reverse transcriptase-polymerase chain reaction was performed for IL-1beta, tumor necrosis factor-alpha, IL-12 p35, and IL-12 p40. Exposure to HDM led to a significant upregulation of mRNA of these cytokines in atopic patients only. Whereas IL-1beta and tumor necrosis factor-alpha also showed an upregulation in part of these patients after exposure to the irritant sodium lauryl sulfate, IL-12 p40 mRNA was exclusively enhanced by the application of the allergen. In contrast to IL-12 p40, IL-12 p35 mRNA was not detectable in significant amounts. Interestingly, also in untreated, normal appearing skin of atopic individuals (n = 16), the levels of these cytokines were higher than in normal individuals (n = 8), possibly explaining the increased skin irritability of atopic individuals. Finally, comparing epidermal cytokines in the skin of patients who developed a positive allergen patch test to those who stayed negative, suggests that only expression of IL-1beta mRNA may be a predictive marker for the development of a positive patch test reaction to HDM.

Animals↗

Human keratinocytes constitutively express IL-4 receptor molecules and respond to IL-4 with an increase in B7/BB1 expression.

In certain pathological conditions, such as atopic dermatitis, interleukin-4 (IL-4) can be detected in the skin. As the role of this cytokine in inflammatory skin lesions is not completely clear, we investigated its biological effects on skin keratinocytes. It was found that freshly isolated as well as cultured keratinocytes obtained from normal individuals express mRNA for the IL-4 receptor (IL-4R) and produce IL-4R protein, as determined by flow cytometry. Moreover, IL-4 induced a proliferative response in keratinocytes after 1 day of culture and enhanced B7/BB1 expression in these cells. B7-2 (CD86) mRNA and protein were neither detected on untreated nor IL-4 treated keratinocytes. In contrast to interferon-gamma (IFN-gamma), IL-4 did not induce ICAM-1 (CD54) or HLA-DR-expression. Keratinocytes which had been treated with IL-4 showed an enhanced ability to stimulate allogeneic T-cell proliferation in the presence of staphylococcus enterotoxin B (SEB), (p < 0.01). Neutralizing anti-B7/BB1 monoclonal antibodies did not block this effect. These results indicate that other molecules than B7/BB-1. HLA-DR or ICAM-1 on IL-4-activated keratinocytes may be involved in T-cell stimulation. In conclusion our results suggest that locally produced IL-4, besides modulating keratinocyte membrane molecules, may enable keratinocytes to interact with skin infiltrating lymphocytes.

Antigens, CD↗