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D Van Neste† RM Trüeb‡ 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):578-583
BACKGROUND: Computer-assisted image analysis has been proposed for human hair growth studies. METHODS: The performances of Trichoscan, a commercially available automated system combining epiluminiscence microscopy with digital image analysis, developed for office-based hair growth measurements, have been evaluated comparatively on the same skin sites using standardized photographic equipment and calibrated processing for contrast-enhanced phototrichogram (CE-PTG) analysis. This reference method has been validated with scalp biopsies and histological examination of serial sectioning. RESULTS: Besides edge effects, hair fibres escaped the Trichoscan analysis for various reasons including, but not limited to, thickness, pigmentation, closeness and crossing. CONCLUSION: Most of these problems have been identified in the late 1980s and remain largely unsolved by the processing software that was evaluated in 2004. Therefore claims promoting the Trichoscan method for accurate hair measurements in clinical trials on scalp and body hair are not supported by the present investigation. The speed at which the analysis is performed is outweighed by the errors in signal detection. Therefore we suggest that improvements must be clearly documented before Trichoscan is established for quantified diagnostic purposes and detailed hair cycle monitoring during hair trials. 相似文献
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Association of glomerular and interstitial mononuclear leukocytes with different forms of glomerulonephritis 总被引:1,自引:0,他引:1
J Markovic-Lipkovski C A Müller T Risler A Bohle G A Müller 《Nephrology, dialysis, transplantation》1990,5(1):10-17
Immunophenotyping of mononuclear leukocytes was performed in renal tissue obtained from 69 patients with different forms of glomerulonephritis (GN) and from ten donors' kidneys for transplantation used as controls. A panel of monoclonal antibodies was used in the immunoperoxidase technique on frozen sections to define B- and T-lymphocyte subpopulations, NK cells and monocytes/macrophages, as well as the expression of HLA class II antigens-DQ, -DR and -DP. Quantification of labelled leukocytes revealed a significant increase of CD4+ and CD8+ T-cells in glomeruli of rapidly progressive glomerulonephritis, membranoproliferative glomerulonephritis and even of focal gomerulosclerosis. The number of glomerular monocytes/macrophages was significantly increased only in rapidly progressive glomerulonephritis, whereas in membranoproliferative glomerulonephritis it was decreased. No differences to normal tissue were detected in glomeruli for all other types of inflammatory cells. Interstitial cells were mostly T-lymphocytes in all forms of glomerulonephritis. In all groups the CD4+/CD8+ ratio was somewhat greater than 1 and even about 2 in rapidly progressive glomerulonephritis. Only in particular case was this ratio inversed. High expression of HLA class II antigens was observed on interstitial mononuclear leukocytes, as a sign of their activation. The excess of HLA-DQ-positive cells over the sum of CD14+ and CD20+ cells provides evidence not only for presence of activated T-lymphocytes but perhaps also for accumulation of renal dendritic cells in the interstitium in glomerulonephritis associated with interstitial infiltration. 相似文献
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V Schleyer† S Radakovic-Fijan‡ S Karrer† T Zwingers§ A Tanew‡ M Landthaler† RM Szeimies† 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):823-828
BACKGROUND: Based on good results in the treatment of superficial skin tumours, since the early 1990s topical photodynamic therapy with aminolaevulinic acid (ALA PDT) has been used for disseminated, inflammatory dermatoses including psoriasis. However, there is still a lack of well-documented trials. OBJECTIVE: A prospective randomized, double-blind phase I/II intrapatient comparison study was conducted in 12 patients to investigate whether topical ALA PDT is an effective treatment for chronic plaque-type psoriasis. METHODS: In each patient three psoriatic plaques were randomly treated with a light dose of 20 J/cm(2) and 0.1%, 1% and 5% ALA, respectively. Treatment was conducted twice a week until complete clearance or for a maximum of 12 irradiations. Therapeutic efficacy was assessed by weekly determination of the psoriasis severity index (PSI). RESULTS: The mean percentage improvement was 37.5%, 45.6% and 51.2% in the 0.1%, 1% and 5% ALA-treated groups, respectively. Irradiation had to be interrupted several times because of severe burning and pain sensation. CONCLUSION: Topical ALA PDT did not prove to be an appropriate treatment option for plaque-type psoriasis due to disappointing clinical efficacy, the time-consuming treatment procedure and its unfavourable adverse event profile. 相似文献
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B. Jahn-Schmid C. Harwanegg† R. Hiller† B. Bohle C. Ebner O. Scheiner M. W. Mueller† 《Clinical and experimental allergy》2003,33(10):1443-1449
BACKGROUND: The availability of recombinant allergens and recent advances in biochip technology led to the development of a novel test system for the detection of allergen-specific IgE. OBJECTIVE: To test the performance of this allergen microarray in a serological analytical study. METHODS: Standard allergens contained in grass pollen (Phl p 1, Phl p 2, Phl p 5 and Phl p 6) and tree pollen (Bet v 1 and Bet v 2) were used as a model system. The detection of allergen-specific serum IgE using microarrays was compared with standard test systems: CAP/RAST and an in-house ELISA. In order to test the analytical sensitivity of the assays, geometric dilutions of a serum pool containing high levels of pollen-specific IgE from allergic individuals were tested in each system. To assess the analytical specificity, the sera of 51 patients with presumptive allergic symptoms were collected before diagnosis. Thereafter, the results for grass/tree-pollen-specific IgE were compared. RESULTS: The microarray has a good dynamic range similar to the CAP/RAST system. Microarray and ELISA showed comparable analytical sensitivity exceeding the CAP/RAST system. With respect to the analytical specificity, no significant cross-reactivity of the allergens was observed. For two of the allergens tested, weak positive signals were detected in the microarray test system, whereas they were not detectable by CAP/RAST. CONCLUSION: A good correlation of presently used methods to detect serum IgE and the novel microarray test system was observed. As a next step, a careful validation of this method for a multitude of allergens and a thorough clinical evaluation has to be provided. Microarray testing of allergen-specific IgE can be presumed to be the method of choice for a prospective component-resolved diagnosis of Type I allergy, and the basis for the design and monitoring of a patient-tailored specific immunotherapy in the future. 相似文献
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The evolution of renal glomerular lesions was examined in biopsies taken from 33 patients with membranoproliferative glomerulonephritis (MPGN). 25 patients had a diffuse form of MPGN in the first biopsy (group A). Twenty-four of them still showed diffuse MPGN in subsequent biopsies, but one patient improved clinically and histologically 19 years after the initial biopsy. Out of 6 patients with focal MPGN in the first biopsy (group B), 4 developed diffuse MPGN, one remained with focal MPGN in the repeat biopsy, and another one was found in remission, as determined by both histological and clinical features. Group C represents two patients who had no histological findings of MPGN on initial biopsy but later showed evidence of a diffuse form of MPGN on subsequent biopsies. Thus, the focal form of MPGN may be found either in the development of diffuse MPGN or in its healing stage, and the prognosis will vary accordingly. 相似文献