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T Gambichler

Publications and source records attributed to T Gambichler.

At least 37 records · Page 2Linked to original sources
PubMed2004

Nephrogenic fibrosing dermopathy.

Nephrogenic fibrosing dermopathy (NFD) is an uncommon, recently described fibrotic skin disorder that has been observed in patients with end-stage renal disease. We describe a 81-year-old man with end-stage renal disease who developed NFD in the seventh year of haemodialysis. Laboratory investigations revealed considerably increased circulating immune complexes and anti double stranded DNA antibodies. Because the pathogenesis of NFD may not entirely be attributable to haemodialysis, the role of circulating factors in the development of cutaneous manifestations requires further investigation.

Aged↗
PubMed2004

Immunohistochemical investigation of mid-dermal elastolysis.

We report a 31-year-old Caucasian woman presenting with remarkable wrinkling on her trunk and proximal extremities. Diagnosis of mid-dermal elastolysis (MDE) was confirmed by Van Gieson's staining. Immunohistochemical investigations revealed enhanced expression of CD34+ and CD68+ cells accompanied by slightly increased expression of CD3+ and CD4+ lymphocytes in lesional skin. Furthermore an elevated cellular expression of matrix metalloproteinase (MMP)-1 and slightly increased presence of MMP-12 positive cells combined with a decrease of tissue inhibitor of metalloproteinases 1 (TIMP-1) positive cells was observed in lesional skin as compared with a control specimen obtained from nonlesional skin. Our data may indicate inflammatory processes and an altered balance between MMPs and TIMPs in MDE. Furthermore CD34+ dendritic fibroblasts and/or histiocytes are possibly involved in the pathogenesis of MDE.

Adult↗
PubMed2004

Effects of repeated sunbed exposures on the human skin. In vivo measurements with confocal microscopy.

BACKGROUND: Ultraviolet (UV) lamps used in commercial sunbeds are usually defined as UVA sources. Although it is well accepted that sunbed exposure significantly increases melanin pigmentation, its capacity to induce epidermal thickening is discussed controversially. OBJECTIVES: The aim of this study was to assess non-invasively the effects of repeated sunbed exposures on epidermal thickness, cell size, and pigmentation by means of confocal laser-scanning microscopy (CLSM) in vivo. METHODS: Eight volunteers had sunbed exposures six times in a 3-week period (cumulative dose: 126 J/cm(2) UVA). During irradiation, a small site (2 cm x 2 cm) on the lateral aspect of the inner forearm was covered with a UV-opaque sheet (non-exposed site). CLSM was performed with the Vivascope (Lucid, Henrietta, NY, USA) 24 h after the last UVA exposure on non-exposed sites and UVA-exposed sites that were on the medial aspect of the inner forearm at a distance of 2 cm to the non-exposed measurement site. The following parameters were assessed: thickness of the horny layer (DSC), minimal thickness of the epidermis (E(min)), minimal thickness of the viable epidermis (VE(min)), cell size of the granular layer (A(gran)), and the epidermal melanin content (MI). Additionally, colorimetric measurements have been carried out on non-exposed and UVA-exposed sites. RESULTS: DSC of the UVA-exposed skin was significantly higher than the one of non-exposed sites (mean+/-SD: 15+/-2.9 microm vs. 12.8+/-3 microm). Although E(min) was significantly higher in UVA-exposed sites (mean+/-SD: 40.4+/-3.6 microm vs. 39+/-2.9 microm), a slight but not statistically significant (P>0.05) decrease of VE(min) was observed (25.5+/-2.1 microm vs. 26.2+/-2.4 microm). The median of cell size of the granular layer (A(gran)) significantly (P=0.008) differed between non-exposed (752.1 microm(2)) and UVA-exposed sites (600 microm(2)). MI was significantly (P=0.014) higher for the UVA-exposed skin (1.12 vs. 1.34). Accordingly, colorimetry revealed significantly (P< 0.01) lower skin brightness for UVA-exposed sites (L*=60.2+/-4.3) as compared with non-exposed sites (L*=63.4+/-3.9). CONCLUSIONS: Sunbed exposures seem to induce photoadaptation not only by skin pigmentation but also by epidermal thickening that is predominantly due to an increase in thickness of the horny layer. Moreover, our data indicate that UVA radiation has an influence on the cell size of the granular layer. CLSM is a promising tool for photobiological studies in vivo.

Adaptation, Physiological↗
PubMed2004

Histomorphologic correlation with routine histology and optical coherence tomography.

BACKGROUND: Optical coherence tomography (OCT) is a new and promising diagnostic technique for investigation of skin tumours. We describe a method that makes evaluation and definition of specific morphologic structures of skin tumours via OCT more accurate. MATERIALS AND METHOD: We investigated three patients with basal cell carcinoma and three patients with melanocytic nevi. Three-dimensional (3D) images were obtained from these skin tumours via OCT according to previously applied marks, which were tattooed with special histological marking dye after excision of the tumours. Corresponding to these marks, we investigated serial histological sections (haematoxylin&eosin staining). RESULTS: We could prove similar morphological structures both in OCT and histology. Due to tissue deformation, the compared measurements of structures like cell nests or epidermal thickness were slightly deviated. However, by this method we could prove similar tissue formations in OCT and histology. CONCLUSIONS: Due to the deformation by histological processing and slightly different sectioning levels, the comparison of histological pictures and OCT images seems difficult. Nevertheless, in two cases it was possible to demonstrate the same morphological structures with OCT imaging and histological investigation. Our method could play an important role for further evaluation of OCT images. We estimate better evaluation of OCT imaging using a 3D reconstruction method.

Basal Cell Carcinoma↗
PubMed2003

Hepatitis B-assocciated adult-onset Still's disease presenting with neutrophilic urticaria.

Adult-onset Still's disease (AOSD) is an uncommon systemic inflammatory disorder that is characterized by quotidian fever, articular manifestations, neutrophilic leukocytosis, and maculopapular rash. The aetiology of the disease is unknown, however, an infectious cause has been suggested. Here we describe a patient in whom neutrophilic urticaria was the cutaneous manifestation of AOSD. In addition, the patient suffered from chronic hepatitis B infection that may be a potential trigger factor of AOSD. In patients with AOSD, serological investigations for detection of infection should include hepatitis serology. Further, we suggest that urticarial lesions may be a more common cutaneous manifestation of AOSD than has been recognized previously. Thus it is important to include AOSD in the differential diagnosis of urticaria.

Adult↗
PubMed2003

[Noninvasive diagnosis of skin functions].

Noninvasive investigation of skin functions is increasingly employed in dermatology and cosmetology. It enables one to study aspects of skin functions that cannot always be appreciated by sensory perception. Noninvasive methods permit objective and reproducible investigation of distinct biophysical parameters. In the age of evidence-based medicine this becomes more and more important. Biophysical data can be quantified, analyzed, and stored electronically. In an overview, selected noninvasive techniques of skin function testing are introduced and their relevance in dermatology, dermatopharmacology, and cosmetology is discussed.

Aged↗
PubMed2003

Sun protection offered by fabrics: on the relation between effective doses based on different action spectra.

BACKGROUND: Ultraviolet (UV) radiation threshold levels have been suggested by the International Commission on Non Ionising Radiation Protection (ICNIRP). The ICNIRP action spectrum differs from the action spectrum proposed by the International Commission on Illumination (CIE). Industrial hygienist employs the first approach while dermatologists and photobiologists commonly use the CIE spectrum. OBJECTIVES: By means of the ICNIRP and CIE action spectra we aimed to calculate the ultraviolet protection factor (UPF) for clothing as a function of the UV index, and to elucidate the relation between the two action spectra. METHODS: Using a theoretically calculated solar spectrum that was determined by means of radiation transfer modelling the relation between the effective doses were assessed which were obtained by using the ICNIRP or the CIE action spectra. Employing the guidelines set out by the ICNIRP and the CIE the protection requirements for clothing were also calculated. RESULTS: It was found that the UPF of a textile material should be at least 2.25 times the maximum UV index observed on a cloudless day to comply with the guidelines of the CIE, or should be at least 4.13 times the maximum UV index to comply with the guidelines of the ICNIRP. CONCLUSIONS: In Northern Europe a UPF 40 + should indeed comply with the exposure limits (EL) proposed by the CIE or ICNIRP. However, in Southern Europe, where UV index can, as in Australia, be as high as 11 the EL can in principle be exceeded for outdoor workers or individuals staying outside the whole day. Taken into consideration the exposure geometry a clearly lower UPF seem to be sufficient in a realistic exposure situation. Nevertheless we recommend a UPF 40 + that is sufficient in extreme exposure situations in every geographical location and also resistant against UPF-decreasing effects ('worst case scenario').

Guidelines as Topic↗
PubMed2003

Diagnostic and neural analysis of skin cancer (DANAOS). A multicentre study for collection and computer-aided analysis of data from pigmented skin lesions using digital dermoscopy.

BACKGROUND: Early detection of melanomas by means of diverse screening campaigns is an important step towards a reduction in mortality. Computer-aided analysis of digital images obtained by dermoscopy has been reported to be an accurate, practical and time-saving tool for the evaluation of pigmented skin lesions (PSLs). A prototype for the computer-aided diagnosis of PSLs using artificial neural networks (NNs) has recently been developed: diagnostic and neural analysis of skin cancer (DANAOS). OBJECTIVES: To demonstrate the accuracy of PSL diagnosis by the DANAOS expert system, a multicentre study on a diverse multinational population was conducted. METHODS: A calibrated camera system was developed and used to collect images of PSLs in a multicentre study in 13 dermatology centres in nine European countries. The dataset was used to train an NN expert system for the computer-aided diagnosis of melanoma. We analysed different aspects of the data collection and its influence on the performance of the expert system. The NN expert system was trained with a dataset of 2218 dermoscopic images of PSLs. RESULTS: The resulting expert system showed a performance similar to that of dermatologists as published in the literature. The performance depended on the size and quality of the database and its selection. CONCLUSIONS: The need for a large database, the usefulness of multicentre data collection, as well as the benefit of a representative collection of cases from clinical practice, were demonstrated in this trial. Images that were difficult to classify using the NN expert system were not identical to those found difficult to classify by clinicians. We suggest therefore that the combination of clinician and computer may potentially increase the accuracy of PSL diagnosis. This may result in improved detection of melanoma and a reduction in unnecessary excisions.

Adult↗
PubMed2003

Mechanisms of apoptosis: UVA1-induced immediate and UVB-induced delayed apoptosis in human T cells in vitro.

OBJECTIVE: The decreased number of lymphocytes combined with the induction of apoptosis and necrosis seems to be the key mechanism of many phototherapeutic agents. The purpose of our study was to determine the regulating pathway, time course and dose dependence of UVA1- vs. UVB-induced cell death in human T lymphocytes. METHODS: In our study we applied an in vitro method using single-laser flow cytometry differentiating between intact (Annexin V-FITC-/PI-), apoptotic (Annexin V-FITC+/PI-) and necrotic T cells (Annexin V-FITC+/PI+) following UVA1 (340-400 nm) or UVB (280-320 nm) irradiation. Additionally, fluorescence microscopy of apoptotic cells was performed using acridine orange and ethidium bromide. RESULTS: Compared to DNA-binding fluorescent microscopy, the flow cytometric method revealed similar, but more precise, results concerning apoptosis and necrosis. Our data indicate that UVB irradiation exerts its effects by the induction of delayed apoptosis within 24-48 h. In contrast, UVA1 irradiation acts via the dose-dependent induction of immediate apoptosis and necrosis within 6 h. CONCLUSIONS: Our findings demonstrate that UVA1 irradiation may effect structural and functional modifications leading to immediate initiation of apoptosis followed by early membrane rupture, whereas UVB irradiation leads to DNA damage followed by delayed apoptosis, obviously without initial membrane alteration.

Adult↗
PubMed2002

Mononuclear cells in atopic dermatitis in vivo: immunomodulation of the cutaneous infiltrate by medium-dose UVA1 phototherapy.

INTRODUCTION: Recently, medium-dose UVA1 phototherapy (50 J/cm2) has achieved great therapeutic success within the treatment of severe atopic dermatitis (AD). Histologically, AD is recognised by a pathological perivascular dermal infiltrate including T lymphocytes, eosinophils and Langerhans cells. The purpose of our study was to investigate the extent to which UVA1 irradiation is able to modulate the mononuclear dermal inflammatory infiltrate using different monoclonal antibodies. PATIENTS AND METHODS: Biopsy specimens before and after treatment with medium-dose UVA1 irradiation (cumulative dose: 750 J/cm2) from 15 patients suffering from severe AD were analysed immunohistochemically concerning the presence of CD4+ and CD8+ T lymphocytes, CD1a+ Langerhans cells and EG2+ activated eosinophils. RESULTS: Compared to lesional skin of patients with AD before UVA1 irradiation, the relative number of CD4+ cells, CD1a+ dendritic cells and activated EG2+ eosinophils within the dermal infiltrate could be decreased significantly after treatment. In contrast, medium-dose UVA1 phototherapy led to a significant increase of the percentage of dermal CD8+ cells. These alterations were closely linked to a decrease of the absolute skin-infiltrating cells and a substantial clinical improvement of the skin. CONCLUSIONS: In summary, our findings demonstrate that medium-dose UVA1 irradiation leads to a remarkable modulation of the dermal mononuclear infiltrate in patients with severe atopic dermatitis referring to a decrease of dermal Langerhans cells, activated eosinophils and CD4 cell count as well as to a relative increase of CD8+ lymphocytes. The immunomodulation of the cutaneous infiltrate is associated with a depletion of cytotoxic agents, the defective IgE overproduction and the aberrant presence of T lymphocytes combined with the pathological cytokine pattern.

Adult↗
PubMed2002

Investigation of basal cell carcinoma [correction of carcionoma] by confocal laser scanning microscopy in vivo.

BACKGROUND/PURPOSE: In vivo confocal laser scanning microscopy (CLSM) allows to study human skin up to 200 micro m deep non-invasively. Aim of this study was to investigate basal cell carcinoma (BCC) using in vivo CLSM, and to compare the micromorphologic features of BCC with uninvolved skin. METHODS: Twelve patients with histological diagnosis of BCC referred to our department for tumor excision were investigated on the lesion(s) and on clinically uninvolved sites preoperatively by in vivo CLSM using the Vivascope 1000 (Lucid Inc., Rochester, USA). The images were compared to histological examinations of the excised tissue. RESULTS: Typical changes in vasculature such as increase in number and diameter of the blood vessels, loss of the vascular architecture, parallelly and horizontally orientated vessels, and accumulation and rolling phenomena of bright reflecting cells of 11.88 +/- 1.75 micro m in diameter along the vessel wall were observed in all BCCs. The tumor stroma of the BCCs showed a strong reflectance mainly due to numerous bundles of collagen fibers encoating dark, cell-rich areas of tumor parenchym. In five patients, slim basaloid cells with relatively large, elongated dark nuclei were observed in the periphery of the tumor parenchym. In the fibrosing type of BCC, curled bundles of collagen with large cells represented the tumor stroma. CONCLUSIONS: BCC can be investigated by CLSM and provide typical features. Besides the tumor parenchym and stroma, typical changes in vasculature seem to be a sensitive criteria for BCC and may in future help in diagnosing BCC by CLSM as well as in assessing the margins of large tumors. We suggest that CLSM is a promising non-invasive tool for the diagnostics of BCC and the assessment of tumor margins prior to surgery.

Aged↗
PubMed2002

Plasma levels of opioid peptides after sunbed exposures.

BACKGROUND: Previous studies have indicated that solar and artificial ultraviolet (UV) radiation have a positive influence on psychological variables such as mood and emotional state. Circulating opioid peptides have been suggested as being important in this effect. OBJECTIVES: To investigate in a controlled trial the influence of UVA radiation on opioid peptide levels. METHODS: We determined plasma levels of beta-endorphin immunoreactive material (IRM) and met-enkephalin in UV-exposed (n = 35) and non-exposed (n = 9) healthy volunteers. On the first day of the study, blood samples were taken from the volunteers (time A). UVA irradiation was subsequently administered with an air-conditioned tanning device. During the UV exposures the volunteers wore opaque goggles. Twenty minutes after UV exposure, blood samples were collected again (time B). Within the following 3 weeks the volunteers had a series of five UV exposures. On the last day of the study (24 h after the sixth UV exposure) blood samples were collected (time C). The cumulative UVA doses were 96 J cm-2 for skin type II and 126 J cm-2 for skin type III. The controls had no UV exposures. Plasma beta-endorphin IRM and met-enkephalin levels were determined using radioimmunoassays. RESULTS: At all times of blood collection (A, B, C), there were no significant differences in plasma levels of beta-endorphin IRM and met-enkephalin between UV-exposed and non-exposed volunteers (P > 0.05). CONCLUSIONS: UVA irradiation does not significantly elevate plasma levels of beta-endorphin IRM and met-enkephalin. Therefore we suggest that psychological benefits claimed to occur after UV exposure are unlikely to be mediated by the types of circulating opioid peptides measured in this study.

Adolescent↗