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M Stücker

Publications and source records attributed to M Stücker.

At least 37 records · Page 2Linked to original sources
PubMed2003

Fibrinogen adsorption--a new treatment option for venous leg ulcers?

The initial element in the causation of venous ulceration is a disturbance of venous blood flow that leads to an increase in venous pressure. Eventually, however, it is the microcirculatory consequences of venous hypertension that lead to trophic skin changes and finally to ulceration. A reduction in blood viscosity results in an improvement at the microcirculatory level. The elimination of fibrinogen from plasma improves blood viscosity. This case report concerns a 75-year-old woman with venous ulcers of both legs (left lower leg: deep ulceration with a surface area of 3 x 5 cm; right lower leg: superficial, confluent ulceration with a total surface area of 5 x 10 cm). The patient underwent 20 sessions of fibrinogen adsorption, while simultaneously continuing with a regimen of conservative measures (activated charcoal cloth dressing with silver, calcium alginate dressings and short-stretch compression bandages). Following binding to a peptide (Gly-Pro-Arg-Pro-Lys), fibrinogen and fibrin were specifically removed from the patient's plasma: her fibrinogen concentration was lowered from an original mean level of 310 mg/dl (SD +/- 104 mg/dl) to 136 mg/dl (SD +/- 54 mg/dl), and there was no return to the baseline concentration by the time of the next fibrinogen adsorption session. In response to this treatment the patient's ulcers healed rapidly within 9 weeks. Dizziness and hematomas at the vascular access sites in both antecubital fossae were reported as adverse effects. A fall in hematocrit was also noted (before treatment 37% +/- 1%; after treatment 35% +/- 2%). This may have been caused by hemodilution due to the procedure and to cell losses during blood-plasma separation, a phenomenon that is known to occur during apheresis. This case report suggests that fibrinogen adsorption is low in adverse effects and is a useful addition to the range of treatments available for ulcers of venous etiology.

Adsorption↗
PubMed2003

Reflectance spectroscopy can quantify cutaneous haemoglobin oxygenation by oxygen uptake from the atmosphere after epidermal barrier disruption.

BACKGROUND: The supply of oxygen to the viable skin tissue within the upper layers is not only secured by the cutaneous blood vascular system, but to a significant part also by oxygen diffusion from the atmosphere through the horny layer. The aim of this study was to examine whether changes in haemoglobin oxygenation can be observed within the isolated perfused bovine udder skin used as a skin model by removing the upper horny layer by adhesive tape stripping. METHODS: Diffuse reflectance spectroscopy in the visible spectral range was used for non-invasive characterisation of haemoglobin oxygenation in skin under in vitro conditions. Mid-infrared attenuated total reflectance spectroscopy was employed for analysing the surface layer of the stratum corneum with respect to keratin, water and lipid components. Skin barrier disruption was achieved by repeated stripping of superficial corneocyte layers by adhesive tape. RESULTS AND CONCLUSION: Significant changes in skin haemoglobin oxygenation were observed for skin areas with reduced lipid concentration and a reduced stratum corneum layer, as determined from the quantitative evaluation of the diffuse reflectance skin spectra. The result can be interpreted as an increase of oxygen diffusion after the removal of the upper horny layer.

Animals↗
PubMed2002

The cutaneous uptake of atmospheric oxygen contributes significantly to the oxygen supply of human dermis and epidermis.

It has been known since 1851 that atmospheric oxygen is taken up by the human epidermis. The contribution to total respiration is negligible. Until now the significance for the local oxygen supply of the skin has remained unknown. With a newly developed sensor, the oxygen fluxoptode, it has become possible to make local measurements of the transcutaneous oxygen flux (tcJ(O2)). In this study the sensor was calibrated so that absolute values of tcJ(O2) could be reported. At rest, tcJ(O2) was determined on normal, humidified skin on the volar forearm of 20 volunteers of different age groups. In order to evaluate the contribution of the blood flow to the oxygen supply of the skin, tcJ(O2) was recorded at the end of a 5 min suprasystolic occlusion of the forearm. At normal skin surface partial oxygen pressure (163 +/- 9 Torr), tcJ(O2) was 0.53 +/- 0.27 ml O2 min(-1) x m(-2). A 5 min interruption of blood flow resulted in an increase of 9.5 +/- 6.3 % in tcJ(O2). The value of tcJ(O2) was unaffected by the age of the subject. Published data on the oxygen diffusion properties of skin and simulations of intracutaneous profiles of oxygen partial pressure indicated that under these conditions, the upper skin layers to a depth of of 0.25-0.40 mm are almost exclusively supplied by external oxygen, whereas the oxygen transport of the blood has a minor influence. As a consequence, a malfunction in capillary oxygen transport cannot be the initiator of the development of superficial skin defects such as those observed in chronic venous incompetence and peripheral arterial occlusive disease.

Adult↗
PubMed2002

[In vivo differentiation of pigmented skin tumors with laser Doppler perfusion imaging].

BACKGROUND AND OBJECTIVE: Malignant melanomas show a higher heterogeneity in their architecture and a higher vessel density because of neovascularization compared to benign melanocytic skin tumours. In this study the validity of the newly developed Laser Doppler Perfusion Imager (LDPI) with a lateral resolution of 100 microns in the differential diagnosis of pigmented skin tumours was investigated. PATIENTS/METHODS: The perfusion of 116 pigmented skin tumours was s measured with LDPI; 44 malignant melanomas, five melanoma metastases, 59 dysplastic nevi and eight basal cell carcinomas were studied before excision for precise histological diagnosis. RESULTS: There is a significantly higher perfusion of the malignant melanomas (3.15 +/- 1.87 AU) compared to dysplastic nevi (1.14 +/- 0.97 AU) (p < 0.01). By calculating a ratio of the mean perfusion in the tumour and the mean perfusion in adjacent healthy skin, the potential source of error because of regional differences in perfusion is eliminated. The ratio of malignant melanomas (10.78 +/- 9.18) is significantly higher than these of melanoma metastases (4.20 +/- 1.66), basal cell carcinomas (3.24 +/- 1.32) and dysplastic nevi (2.85 +/- 1.32). CONCLUSIONS: The high resolution LDPI has the potential to be a non-invasive screening method for preoperative differential diagnosis of pigmented skin tumours. Besides the epiluminescence microscopy and sonographic determination of the tumour thickness, we have now the possibility to get preoperative information about tumour vascularization.

Adult↗
PubMed2002

[Basal cell carcinoma of the foot. Is the pedoscope a risk factor?].

Basal cell carcinomas of the foot are absolutely rare. We describe the case of a 72-year-old female patient who developed a multicentric superficial BCC present on the lateral edge of the right foot. The patient remembers the regular control of the fit of footwear by an X-ray apparatus, the so-called shoe fluoroscope (=Pedoskop in Germany). Probably this may be a hardly estimated risk factor in the genesis of BCC of the foot.

Aged↗
PubMed2002

Guidelines for visualization of cutaneous blood flow by laser Doppler perfusion imaging. A report from the Standardization Group of the European Society of Contact Dermatitis based upon the HIRELADO European community project.

This report reviews how to set up a laser Doppler perfusion imaging system intended for visualization of skin blood perfusion, capture images and evaluate the results obtained. A brief summary of related papers published in the literature within the areas of skin irritant and allergy patch testing, microdialysis and skin tumour circulation is presented, as well as early applications within other fields such as diabetology, wound healing and microvascular research.

Humans↗
PubMed2002

Instrumental evaluation of retinoid-induced skin irritation.

BACKGROUND/PURPOSE: Retinoids like tazarotene are approved for the treatment of chronic plaque psoriasis. In the beginning of topical retinoid therapy, 15-20% of the patients suffer from mild to moderate adverse reactions with burning and erythema. The aim of the study was to find predicative parameters of the individual irritative potential and to suggest options to reduce these initial irritations. METHODS: Twenty in-patients with different skin types (1 + 2: 11, 3 + 4: 9), with chronic plaque psoriasis were included in this open study. In each patient, 7 randomized plaques on the forearm were treated for 14 days on different ways: test area 1: morning (m) and evening (e) placebo, test area 2: placebo (m) and tazarotene 0.05% (e), test area 3: placebo (m) and tazarotene 0.1% (e), test area 4: calcipotriol (m) and calcípotriol (e), test area 5: mometasone furoate (m) and tazarotene 0.05% (e), test area 6: mometasone furoate (m) and tazarotene 0,1% (e), test area 7: placebo (m) and tazarotene in increasing concentrations (e), test area 8: healthy skin for control. Before and after therapy, skin barrier function, blood flow and plaque thickness in 20-MHz sonography were assessed in different test areas intraindividually by non- invasive biophysical measurements. RESULTS: After 14 days of therapy, tazarotene 0.05% and 0.1% produced a stronger increase of laser Doppler flow in patients with skin type 1 and 2 than in patients with skin type 3 and 4. When using the combination therapy of tazarotene and mometasone, the laser Doppler flow was significantly lower than in tazarotene as monotherapy. 20-MHz-ultrasound showed a significant decrease in the thickness of the echo-poor band in all topical therapy regimens compared to placebo. Patients of skin type 1 and 2 reached a higher density of the dermis than patients of skin type 3 and 4, meaning a stronger decrease of inflammatory infiltration and acanthosis. CONCLUSION: Adapting retinoid therapy to the patient's skin type can reduce the initial irritative side-effects. During the first days, patients with skin type 1 or 2 should add a medium potency corticosteroid. Stronger skin irritation caused by tazarotene therapy increases therapy effects.

Administration, Cutaneous↗
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↗
PubMed2001

[Occult dermal primary melanoma in congenital nevus-cell nevus].

Malignant melanomas normally arise at the dermoepidermal junction. Development of these tumours in deeper layers of the dermis without having contact with the junction is rare. A small congenital melanocytic nevus localized in the region of the waist band was excised because of mechanical irritation; it had not shown any changes over years. A thorough examination of the whole body did not give any clue to a malignant melanoma. Histologically a compound nevus with the typical architecture of a congenital melanocytic nevus was found. In the deeper dermis there was an isolated nodule of extremely atypical melanocytes with minimal pigmentation of melanin. S100 antigen could be demonstrated throughout the whole tumour whereas HMB45 was only found at the dermoepidermal junction. There was no marking of the tumour cells with a pancytokeratin antibody. A histological relationship between the new tumour and a mixed tumour of the left testicle, which had been excised 3 years ago, could be excluded. We did not find any metastases neither by image-aided methods nor by sentinel lymph node biopsy.

Adult↗
PubMed2001

[What remains of the skin after 2000 years in a bog?].

BACKGROUND AND OBJECTIVE: Mummies have an important place in the study of archaeology and paleopathology because they are so well preserved. For the first time skin samples of six 2300-1600 year old bog bodies from North Germany were examined by histology, transmission electron microscopy and immunohistology. METHODS: For histology the samples were stained with H&E and van Gieson elastic stain. Fixation and embedding in epoxy followed for the transmission electron microscopy. Specific antibodies directed to type IV collagen and S-100 were used. RESULTS: Histologically it was possible to observe collagen bundles in the dermis, with a density similar to recently stained samples. Epidermis was not preserved. The electron microscopy showed collagen fibrils with a diameter of 45-110 nm and the characteristic axial periodicity. Throughout the dermis, a number of spores of bacteria with a diameter of 0.83 +/- 0.051 micron and an electron dense core were found. No activity against the used antibodies could be detected. CONCLUSIONS: Histology and electron microscopy demonstrate the excellent conservation of the dermal collagen in the bog. In contrast to ice mummies like "Otzi" and mummies from Egypt, no cellular elements could be found in the skin of bog bodies.

Collagen↗
PubMed2001

[Correlation between histopathology and epiluminescent microscopy in nonmelanocytic skin lesions].

Epiluminescence microscopy techniques make surface and subsurface structures accessible to visual examination in vivo. The visualization of a multitude of special morphological features, such as blood vessels, adnexa and deposits of pigments in normal and pathologically changed skin allows a reproducible and topographical stratification. There is a chance of identifying the architecture of the stratum corneum, the epidermis and the papillary bodies. Changes in the amount of melanin can be individually assessed in the stratum corneum and the deeper layers extending into the upper dermis. It is possible to differentiate the orientation, size and color of the blood vessels of the cutaneous vascular plexus, involving the capillaries of the stratum papillare and the subpapillary plexus.

Equipment Design↗
PubMed2001

Low-dose ultraviolet-A1 phototherapy for lichen sclerosus et atrophicus.

Lichen sclerosus et atrophicus (LSA) is a chronic inflammatory skin disease characterized by white porcelain-like sclerotic skin lesions. It is most commonly seen in adult females and usually affects the genitoanal area. Extragenital LSA appears in 15-20% of cases. We report a 9-year-old Caucasian girl suffering from extragenital LSA that was resistant to conventional treatment. After 40 treatment sessions with low-dose UVA1 phototherapy, all skin lesions were resolved completely. Moreover, the improvement of skin status has been sustained during 6-months of follow-up. Long-wave UVA irradiation has been shown to induce intensively collagenase activity in human dermal fibroblasts. We suggest that UVA1 irradiation could be an effective treatment in patients suffering from extragenital LSA.

Child↗