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W N Meigel

Publications and source records attributed to W N Meigel.

At least 19 recordsLinked to original sources

Efficiency of acitretin in combination with UV-B in the treatment of severe psoriasis.

Compared with the antipsoriatic retinoid etretinate, the new aromatic retinoid acitretin represents an important advance due to its rapid elimination kinetics. Since in psoriasis vulgaris retinoids are used predominantly in combination regimens, we investigated the therapeutic efficacy of acitretin and UV-B compared with placebo and UV-B in a double-blind, randomized multicenter trial in 82 patients with severe psoriasis. They were treated with 35 mg of the study medication during the first 4 weeks of therapy and 25 mg thereafter, concomitantly with UV-B irradiation in increasing energy doses. Forty patients who underwent therapy with acitretin and UV-B and 38 patients who underwent therapy with placebo and UV-B were evaluated for efficacy. The target variables--psoriasis severity index and total UV-B dose--were reported at intervals of 2 weeks over a maximum period of 8 weeks. At the end of treatment, the psoriasis severity index decrease was 79% in the acitretin and UV-B group and 35% in the placebo and UV-B group. The response rate, defined as greater than or equal to a 75% decrease of the psoriasis severity index, was 60% for the combination treatment and only 24% for the control treatment. This treatment response was achieved with markedly lower cumulative UV-B energy. The median cumulative UV-B energy applied to reach 75% clinical improvement was 11.8 J/cm2 vs 6.9 J/cm2. Side effects showed a similar pattern in both groups. Our data show that the acitretin dramatically improves the results of UV-B treatment in patients with severe psoriasis. In addition, it markedly decreases the effective cumulative UV-B dose, thereby reducing the potential long-term hazards of UV irradiation. We conclude that the acitretin plus UV-B combination treatment represents a highly effective therapeutic regimen in severe psoriasis.

Acitretin

[Dermatologic aspects of HIV infection].

We report on the clinical course, the staging, and the theories regarding the etiopathogenesis and possible prognostic factors of Kaposi's sarcoma. In addition, we refer to the significance of viral, mycotic, and bacterial infections in HIV infection.

Acquired Immunodeficiency Syndrome

Nature of collagen in dermatofibrosarcoma protuberans.

The nature of collagen from 2 cases of dermatofibrosarcoma protuberans was studied. For this purpose, the tumor tissue was carefully separated from adjacent normal dermis. The collagen types comprised in the tumor were identified by CM-cellulose chromatographic and SDS-gel electrophoretic analysis of the component alpha-chains. Semiquantitative evaluation of the relative type III content was established by separation of the cyanogen bromide peptides on gels of 12% polyacrylamide in SDS. These studies showed that dermatofibrosarcoma protuberans contains alpha 1(I)-, alpha 2-, and alpha 1(III)-chains as well, and corresponding type I- and type III-related CNBr peptides. Comparing the collagen from dermatofibrosarcoma protuberans to that of normal skin, the relatively increased type III content in the case of dermatofibrosarcoma protuberans becomes apparent.

Adult

Collagen polymorphism in pathologic human scars.

The collagen type composition of normal and pathologic scars was examined in comparison with normal skin from the same individual. Particular care was taken to separate scar tissue from adjacent normal dermis. After urea extraction, the tissue specimens were cleaved with cyanogen bromide. The presence of the dermal collagen types I and III was deduced from the electrophoretic distribution patterns of the CNBr peptides in 12% SDS-polyacrylamide gels. The intensity of the type III specific peptide bands correlates with the type III content of the samples. Using this method, the presence of both type I and III collagen can be proved in normal as well as pathologic scars. The type III content in older normal scars is slightly increased, whereas the type III content of pathologic scars is significantly increased in comparison with the type III content of normal skin. The electrophoretic CNBr peptide distribution pattern of pathologic scar tissue is almost the same as that of fetal skin. Both are clearly different from the peptide pattern of normal adult skin.

Adult

Collagen in the cellular and fibrotic stages of scleroderma.

The collagen in localized and systemic scleroderma skin was studied by light microscopy with silver impregnation (50 patients), electron microscopy (14 patients), and immunofluorescence microscopy using specific antibodies against Type I and Type III collagens (12 patients). In the cellular stage, the dermis and adipose tissue revealed perivascular or diffuse cellular infiltrates (mostly lymphocytes, plasma cells, and macrophages), accompanied by deposition of Type III collagen. The lower dermis also showed an increase in Type III collagen. In the fibrotic stage, the papillary layer showed a reduction and/or clumping of Type III collagen as compared to normal skin. The lower dermis and the adipose tissue revealed compact collagen consisting exclusively of Type I collagen or a mixture of Type I and Type III collagen. The pattern of Type III collagen distribution was similar to that of reticulin, thus suggesting that at least some reticulin fibrils may represent Type III collagen.

Adipose Tissue

Dermal architecture and collagen type distribution.

The human dermis consists of two morphologically different layers. A loose meshwork of thin collagenous fibres is characteristic for the adventitial dermis with includes the papillary and the periadnexal dermis. Thick, coarse collagen bundles are the main feature of the reticular dermis. Two different collagens, type I and type III occur in the dermis as shown previously by biochemical analyses. Antibodies specific for type I collagen or type III collagen and their corresponding precursors were used in indirect immunofluorescence tests to localize the various collagens in frozen sections of normal adult skin. Whereas type I collagen is found in all dermal layers, the main part of type III collagen can be found within the adventitial dermis. Antibodies against the precursor of type I collagen stain only a bandlike region immediately beneath the epidermis. Antibodies against the precursor of type III collagen stain the same regions as antibodies against the helical part of type III collagen.

Antibodies

SDS-polyacrylamide gel electrophoretic determination of type I and type III collagen in small skin samples.

A sodium dodecylsulfate-polyacrylamide electrophoretic method, which in contrast to other biochemical procedures, e.g. differential salt precipitation or ion exchange chromatography and molecular sieve chromatography, is applicable to smallest amounts of protein, is shown to be suitable for the determination of the collagen types from small skin samples, such as routine skin biopsies. After urea extraction, the tissue samples are cleaved with cyanogen bromide. The resulting CNBr peptides derived from the different alpha-chains are resolved in 12% SDS-polyacrylamide gels. Densitometric profiles of the gel electrophoretic patterns correspond to the collagen type content of the tissue specimens. Comparing fetal to adult skin, the higher content of type III collagen in the case of fetal skin can be demonstrated.

Adult

[Chewing pads, a variant of knuckle pads].

Three young male patients with chewing pads are reported. Their tic-like habit of chewing on the dorsal aspects over the middle joints of fingers I-IV caused a pad-like thickening of soft tissue. These chewing pads are a variant of "false" knuckle pads. The importance of a medical history and dermatological inspection is stressed to avoid unnecessary diagnostic procedures. This harmless augmentation of soft tissue is commonly confused with rheumatoid disease of the fingers, sarcoidosis or pachydermoperiostosis. Patients should be informed of the true nature of their pads, as discontinuation of their chewing habit will resolve their problems.

Adolescent

[The polymorphism of collagen. New viewpoints on the structure and function of connective tissue].

Recent studies have established that connective tissue contains several chemically and genetically distinct collagens. Here we discuss the nature of these proteins, their occurrence in different tissues and their involvement in disease processes. Types I, II and II collagens show some similarities indicating a common origin. Morphological studies using antibodies against the various collagens indicate that the different collagens occur in different anatomical structures. Alterations in the distribution of these collagens are seen in tissues in certain disease states and may cause the loss of normal tissue function.

Age Factors

Zinc therapy in acrodermatitis enteropathica.

An infant is described with acrodermatitis enteropathica, who initially presented with severe and intractable watery diarrhea. Diagnosis was established at the age of eleven weeks. Serum-zinc concentrations were extremely low and urinary zinc excretion was diminished. Eleven days after oral zinc supplement (100 mg elemental zinc per day), the skin lesions had healed. The high therapeutic doses of zinc required for healing are suggestive that zinc malabsorption is an important pathogenetical factor of this disease.

Acrodermatitis

Disturbance in the regulation of the type of collagen synthesized in a form of osteogenesis imperfecta.

Fibroblasts derived from skin biopsies of a patient with a congenital defect of connective tissue revealed a disturbance in collagen synthesis. The defect was found in the mechanism that controls the type of collagen synthesized. Biochemical data as well as evaluation of immunofluorescent micrographs using collagen type-specific antibodies, suggested that the fibroblasts of this patient synthesized type III collagen, at a time and rate which was not found in fibroblasts from an age-matched healthy individual.

Cells, Cultured