Biomedical subjects

U Broby-Johansen

Publications and source records attributed to U Broby-Johansen.

8 recordsLinked to original sources

PubMed1994

Sodium lauryl sulphate penetration in an in vitro model using human skin.

Because of their ability to impair the skin barrier function, detergents constitute a major risk factor for the development of irritant contact dermatitis. Sodium lauryl sulphate (SLS) is a commonly used detergent for experimental studies within the area of irritant contact dermatitis. In the present study, penetration of S35-labelled SLS was studied in an in vitro model using human cadaver skin. The investigations showed that SLS is capable of permeating the skin barrier when applied under occlusion. SLS could be detected in the dermis and the amount of SLS found here was shown to depend on the dose of SLS applied on the skin. Penetration of SLS continued after removal of the SLS applied as a patch test on the skin surface. Considerable inter-individual variation in the penetration of SLS was demonstrated between different donors.

Adult↗

PubMed1990

Ranking of the antipsoriatic effect of various topical corticosteroids applied under a hydrocolloid dressing--skin-thickness, blood-flow and colour measurements compared to clinical assessments.

In 10 patients with chronic plaque type psoriasis one or two plaques affected equally with psoriasis were chosen for study. Five punched out rings of a hydrocolloid dressing were applied to the psoriasis plaque(s). In each circular test area 20 mg of one of the following creams was applied: base, 1% hydrocortisone (DAK), 0.1% triamcinolone acetonide (Kenalogue), 0.1% betamethasone-17-valerate cream (Betnovate), and 0.05% clobetasol proprionate cream (Dermovate). The areas were occluded with a thin film of transparent hydrocolloid dressing (Comfeel Transparent Dressing), for 1 week. Non-invasive measurements (ultrasound skin thickness, laser-Doppler flowmetry, colorimetry) were performed before and after treatment. Therapeutic response was evaluated blindly by clinical score. The measurements showed a decline in blood flow, a decrease in skin thickness, and normalization of colour approaching that of normal skin, the more potent the corticosteroid used. The clinical scores showed the same: the more potent a corticosteroid used, the closer to the score of normal skin. Data on variability and applications of the methods are presented. The study concludes that potent corticosteroids occluded with a hydrocolloid dressing can clear psoriasis in 1 week. Short-course corticosteroid therapy appears harmless and relevant for clinical dermatology.

Administration, Topical↗

PubMed1990

Leukotriene B4 in atopic dermatitis: increased skin levels and altered sensitivity of peripheral blood T-cells.

Employing a radioimmunoassay, de-proteinated suction blister fluid from 12 patients with active atopic dermatitis appeared to contain higher levels of the pro-inflammatory and immunomodulatory mediator leukotriene B4 (LTB4) than suction blister fluid from 12 non-atopic individuals. Indirect support for the identity of the mediator was obtained by HPLC of pooled samples. Nylon wool enriched T cells from six patients with atopic dermatitis and six non-atopic people preincubated with LTB4 (10(-10) M - 10(-8) M) expressed no statistically significant suppression in co-culture with mitogen stimulated autologous mononuclear cells, and there was no difference between atopic and non-atopic T cells in this respect. In contrast, LTB4 induced a dose-dependent reduction in the percentage of phenotypic Leu 2a (suppressor) cells leading to an increased helper/suppressor ratio in five atopic patients that was not observed in five non-atopics. Elevated skin levels of LTB4 may initiate or amplify dermal inflammation, and abnormal T cell response to the mediator may account for the increased helper/suppressor ratio characteristic of patients with atopic dermatitis.

Adult↗

PubMed1990

Cell surface glycosylation patterns in psoriasis.

Cell surface carbohydrates are excellent markers of cellular differentiation and maturation processes due to their great structural and antigenic diversity as well as their known biosynthetic precursor/product relationships. Using a panel of monoclonal antibodies with well-defined carbohydrate specificities we have studied the expression of biosynthetically related antigens in normal and psoriatic skin. Two "families" of carbohydrate structures were investigated. One series of structures based on N-acetyllactosamine chains (type 2 chain: N-acetyllactosamine and fucosylated derivates hereof of H, Lex, Ley and sialyl-Lex) and another based on the simple mucin type core structures (type 3 chain: Tn, T and sialylated derivates hereof as well as the fucosylated derivative, H). Previously we have found these carbohydrate structures define distinct cell layers in stratified squamous epithelia of mucosa of the cheek, esophagus and uterine cervix. In normal and uninvolved epidermis, N-acetyllactosamine and T carbohydrates were found in the spinous cell layer, whereas the fucosylated derivates, H structures, were found in the granular cell layers above. The fucosylated and sialylated derivate of N-acetyllactosamine, sialylated Lex, had the same distribution as N-acetyllactosamine and T structures. This sequential expression of carbohydrates is similar to our previous findings in mucosa. However, in contrast to mucosa, normal skin basal cells did not label. The glycosylation pattern in psoriatic epithelium was changed in two ways. 1) Some carbohydrates (types 2 and 3 chain H and T) were expressed at an earlier stage of cell maturation. 2) The biosynthetic precursors to T structures, Tn and sialyl-Tn, which are not expressed in normal skin, and are often considered cancer-associated antigens, appeared in psoriatic skin. The Tn-antigen was expressed on basal and lower spinous cells, whereas the sialyl-Tn was only found on basal cells above the dermal papillae. The findings in the present work support previous studies of changes in cell surface glycosylation in psoriatic epidermis and demonstrate the appearance of tumor-associated antigens in highly proliferative, but benign, stratified epithelium.

Adult↗

PubMed1990

Irritant patch testing: penetration of sodium lauryl sulphate into human skin.

To clarify the sources of variation in irritant patch testing, variability in delivery of the test substance from the patch test system was studied. An in vitro model was used to study the penetration of sodium lauryl sulphate (SLS) from a patch test system into the skin. Different formulations of SLS applied to the skin for 24 h were studied (aqueous solution and gels), but irrespective of the vehicle used permeation of SLS into the recipient phase was poor. Results were compared to in vivo patch testing in 12 subjects. Approximately 70% of the applied SLS in aqueous solution was released from the patch test system. Release from gels was poorer. High concordance between the in vivo and the in vitro model was found. No correlation was found between the amount of SLS left in the filter disc and the strength of the clinical reaction in vivo.

Adult↗

PubMed1989

Antipsoriatic effect of local corticosteroids--O2-consumption and blood flow measurements compared to clinical parameters.

Ten patients with chronic plaque-type psoriasis were treated topically with the group IV corticosteroid clobetasol propionate cream (Dermovate) with and without occlusion with a semipermeable hydrocolloid dressing (Comfeel Coloplast, Denmark). The effect of treatment was compared with untreated skin and evaluated in terms of (a) O2-consumption as measured by the TCM-2-oxygen monitor from Radiometer, Denmark, (b) blood flow as measured by a laser-Doppler flowmeter (Perimed, Sweden), (c) temperature measurements using thermo-couples and (d) a clinical score. While steroid + occlusion had a very pronounced effect measured by all parameters and apparent after 24 h, the steroid alone was only marginally effective after 7 days. No placebo effect was detectable in untreated skin with the laboratory methods used. It is suggested that the methods described can be used to evaluate other treatment schedules. Recently it has been shown that measurement of oxygen consumption by transcutaneous O2 electrodes might reflect disease activity in psoriatic plaques. Transcutaneous O2 decreases when a tourniquet is applied around the extremity investigated and the decrease per minute has been used as a measure of the metabolism of normal and psoriatic skin. In a later study it was shown that stripping of the skin prior to measuring was essential as a diffusion barrier was present in the horny layer. It has been previously shown that occlusion of an area to which corticosteroid has been applied increases absorption as estimated by the intensity of blanching. In the present study the effect of occlusion and non-occlusion of corticosteroid treated sites in psoriasis has been compared using clinical and laboratory parameters.

Adolescent↗

PubMed1989

Antipsoriatic effect of semi-occlusive treatment--O2-consumption, blood flow and temperature measurements compared to clinical parameters.

Ten patients with plaque-type psoriasis were treated by applying semi-permeable hydrocolloid dressings (Com-feel, Coloplast, Denmark) and the effect compared to untreated skin. The treatment effect was evaluated by: (a) O2-consumption as measured by a TCM-2 oxygen-monitor; (b) blood flow as measured by laser-Doppler flowmetry; (c) temperature measurements using thermocouples; (d) a clinical score. The treatment effect was evaluated after 1, 2 and 7 days and although there was a significant and sustained improvement in the clinical score following Day 7 (P less than 0.05), this was not associated with a significant change in any of the objective measurements during the study (P greater than 0.05). In the same patients the clinical effect of occlusion was evaluated after 21 days in another area. A pronounced effect was observed comparable to, equal to, or better than that of crude coal tar given as daily applications followed by bathing. There was no significant change in any of the parameters at the sites of untreated psoriasis.

Adolescent↗

PubMed1986

Perivascular axillary block VI: the distribution of gelatine solution injected into the axillary neurovascular sheath of cadavers.

Axillary perivascular injection of 50 ml blue-stained gelatine was made in 20 cadavers, and a total dissection of the axilla was performed. The distribution of injected gelatine and the contact between nerves and gelatine were examined on cross-sections of the neurovascular bundle. The spread of gelatine was characterized by: restriction of gelatine to the neurovascular bundle, an upper border of the gelatine which was constantly found to be proximal to the coracoid process, and bulging of the gelatine towards the medial part of the axillary space. Cross-sections of the neurovascular bundle showed the nerves and vessels to be located in the periphery of the gelatine and in close contact with the lateral wall of the axillary space. The median and the ulnar nerves were in all dissections found to be in direct contact with the gelatine, whereas the radial, the musculocutaneous, and the axillary nerves did not always have direct contact with the gelatine. Abduction of the arm to 90 degrees brings the stretched neurovascular bundle close to the lateral wall of the axilla and this compromises perivascular circumferential spread of the injected gelatine. On the basis of the present investigation, it is hypothesized that insufficient circumferential spread is the cause of incomplete axillary blockades, and the perivascular injection of local anaesthetic should consequently be made with the arm along the side of the body.

Aged↗