Biomedical subjects
Publications and source records attributed to C Nieboer.
Cutaneous blood flow was measured by Laser Doppler Flowmetry after topical application of minoxidil lotion, in 9 healthy males with androgenetic alopecia, and other volunteers. No reaction in the cutaneous blood flow was seen after application of 2%, 5%, or placebo minoxidil lotion.
A new method for quantitative culture of Pityrosporum yeasts, the 'tape-method', is presented. Samples for culture were taken from the skin by stripping with 1 cm2 of tape, whereafter the tapes were placed over a drop of sterile olive oil which was pipetted on a Sabouraud medium. Plates were incubated at 37 degrees C, and after 7 days the numbers of Pityrosporum colonies growing under the tapes were counted. With this method a difference in numbers of Pityrosporum colonies between seborrheic dermatitis and normal skin could be discerned. This difference was significant. It appeared that two successive strippings were sufficient for quantitative culture. The 'tape-method' appeared to be a reliable and inexpensive diagnostic tool.
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We have investigated the diagnostic reliability of the immunofluorescence (IF) technique and histopathology in discoid lupus erythematosus (DLE) and lichen planus (LP) and in diseases clinically resembling these (DLE-like and LP-like). In all cases of DLE and LP it was possible to establish the clinical diagnosis with one or both methods, when in initially negative cases the investigations were repeated on fresh biopsies. In DLE the diagnostic specificity of IF was greater than that of histopathology, and the diagnostic sensitivity of the results of both methods together was greater than that of the two methods separately. In LP the diagnostic specificity of both methods was maximal, but IF showed greater diagnostic sensitivity. These differences were not statistically significant. The most important immunohistochemical feature for diagnosis by IF was the incidence and the morphological pattern of IgG along the epidermal basement membrane. This held true for differentiation between LP and DLE and also between DLE and DLE-like diseases. Combination of the results of IF and histopathology gave the most reliable results in DLE. In LP, IF was more reliable than histopathology.
Sensitization to drugs in transdermal therapeutic systems is a common unwanted event. We investigated whether prolonged occlusion of the skin causes skin irritation, and in this way might play a role in the possible induction of sensitization to drugs from these systems. Occlusion was effected with a placebo transdermal therapeutic system and silver-patch test in a time span ranging from eight hours to seven days in five groups of five volunteers. Skin irritation was judged on clinical aspects, histopathologic and immunofluorescence findings, and changes in the Langerhans' cell systems. The results indicate that occlusion with the systems used in this experiment provokes only slight or no skin irritation.
To analyze the role of immune complexes, complement activation and fibrinolysis in chronic urticaria (CU), we performed serological, immunohistochemical and histopathological studies in 20 patients. In addition, the relationship to urticarial vasculitis was investigated. The results indicate that common CU is not associated with vasculitis. Neither circulating immune complexes nor immunoglobulin-complement complexes were found in the vessel walls. Lowered blood levels of complement and fibrinogen were found only in 1 and 3 patients, respectively. Alpha-2-antiplasmin and fibrin degradation products were within normal limits. Our study indicates that CU and urticarial vasculitis are separate entities. Complement activation and fibrinolysis do not appear to play an important role in CU.
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This paper describes two patients who developed an extensive superficial pustular folliculitis on the upper part of the breast, back, shoulders and lateral sides of the upper arms, starting within 24-36 h after exposure to sunlight. Bacteriological, immunohistopathological and photo-experimental investigations failed to reveal a cause for this sunlight-induced dermatosis, which seems not to have been hitherto described.
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A strong positive, allergic patch-test reaction was elicited in 15 patients with an established allergy for a particular allergen. Patches with a marginally irritating concentration of sodium lauryl sulfate (SLS) were applied at fixed distances. The SLS patch situated adjacent to the allergic reaction was significantly enhanced in 12 of 15 patients (P less than 0.01) compared to more distant SLS reactions ("spillover'). Only quantitative differences were observed in the histologic pictures of the different types of reaction. The infiltrate consisted of lymphocytes and histiocytes, mainly located perivascular in the upper dermis. T-cell subsets were assessed with monoclonal antibodies using an immunoperoxidase technique. The distribution of the different T cells was the same for both reaction types. T cells located outside the perivascular infiltrates (e.g., in the epidermal vesicles) were OKT-8-positive (cytotoxic/suppressor T lymphocytes). Immunofluorescence examination did not show different patterns for the allergic or "enhanced toxic' reactions with regard to the presence of immunoglobulins and complement. The "spillover' phenomenon may cause false-positive patch-test reactions.
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Immunofluorescence studies were performed on the sun-exposed (S) and not-sun-exposed (N) skin of 25 healthy volunteers regarding the incidence of the five Ig classes, albumin, fibrinogen, C1q, C4, C3B, C3c, C3d, C5, C3PA and properdin. In addition a comparative study of two so-called anti-complement antisera was made, one (CI) containing anti-(C4+C3a+C3d), the other (CII) anti-(C3B+C3c). In all biopsies the epidermal basement membrane (BM) was stained positively with anti-C3d in a fibrillar, interrupted linear, or granular pattern. A band-like picture of the BM was observed with anti-IgG , anti-albumin and anti-fibrinogen in three biopsies of the S skin. In two other S skin biopsies a lichenoid pattern was found with anti-fibrinogen, anti-C3d and IgM. The latter antiserum caused a weakly positive band-like picture of the BM, occasionally together with granular deposits, more often in the S skin (11) than in the N skin (4). In the capillary walls, granular deposits of IgM, C3d and occasionally C3c were seen in both the S skin (7) and the N skin (13). In the subjacent vessels, globular deposits positive with anti-C3d, C5 and C3c were found predominantly in the S skin. In the M. arrector pili, granular deposits of C3d and, less obviously, C5, properdin and IgM were frequently observed. A band-like, linear, or granular picture of the BM of the adnexal structures was caused by anti-C3d. IgG was found around the sweat gland in about 30%, but the other serum proteins were only rarely present. The IF patterns of the two so-called anti-complement sera showed marked differences, which were apparently caused by the presence of anti-C3d in the CI serum. The significance of these findings for the diagnostic and pathogenetic interpretation of IF results in pathology are outlined briefly.
Four patients with the clinical picture of epidermolysis bullosa acquisita were investigated. Biopsies were taken from the involved and uninvolved areas of the skin and the immunohistochemical and microscopic changes were studied. Direct immunofluorescence showed deposition of IgG and C3/4 in a linear or norched pattern along the epidermal basement membrane in both the involved and the uninvolved skin. In addition IgA (3/4), IgM (1/4), C4 (3/4) and properdin (3/4) could be detected. Indirect immunofluorescence revealed the presence of circulating antibodies against inter alia the epithelial basement membrane zone in one patient. Routine electron microscopy showed that the blister was situated in the dermis leaving the basal lamina in the roof of the blister. With immunoelectron microscopy using peroxidase-labelled antibody the in vivo deposition of IgG was observed just beneath the basal lamina in the dermis of both the perilesional and the uninvolved skin. These observations show that epidermolysis bullosa acquisita is a distinct entity, in which autoimmune mechanisms might possibly play a role.
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