摘要:

Polymorphonuclear leukocyte (PMNL) infiltration is an important characteristic in psoriatic lesions. Elevated concentrations of the chemoattractant eicosanoid leukotriene B4 (LTB4) are present in psoriatic skin. Its chemotactic activity is mediated via high affinity receptors on PMNL. The goal of our work was to ascertain whether PMNL infiltration in psoriasis can be accounted for by functional abnormalities of the circulating PMNL due to alterations in the LTB4 receptor density or affinity (or both). No significant difference was found between patients with psoriasis, healthy controls and patients with another inflammatory dermatosis (atopic eczema) with regard to the binding parameters of LTB4 receptors on PMNL. Our findings suggest that PMNL accumulation in psoriatic skin may be the result of an excess of cutaneous chemoattractant rather than the increased readiness of psoriatic PMNL to migrate towards LTB4 due to altered LTB4 receptor density or affinity.

ISSN:0302-3427    

DOI:10.1159/000210802

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

Recently the treatment of psoriasis with vitamin D3, its metabolites or analogues, has been reported to be clinically effective and free from side effects. We have quantified the changes in the levels of epidermal lesional keratins in 15 psoriatic patients receiving oral 1α(OH)D3 treatment. Lesions were sampled before treatment commenced and at monthly intervals for 4–6 months. Clinical resolution occurred in 7 patients within this time; 3 other patients showed incomplete lesion resolution and the remaining 5 patients showed a complete lack of response within the treatment period. Lesion resolution, as judged by clinical criteria, was accompanied by significant changes in the levels of three of the keratin polypeptides and smaller changes in others. Keratin 2 increased to levels greater than those in normal epidermis, while keratins 16 and 18 decreased to normal levels. Changes in the levels of keratins 1 and 5 were small and those of keratins 7, 10 and 14 minimal. These changes were compared with values found during lesion resolution with other therapies used in psoriasis, i.e. topical dithranol, PUVA, oral etretinate and hydroxyurea and were highly reminiscent of those observed during PUVA therapy but contrasted with those during etretinate treatment. The decrease in level of keratin 16, a hyperproliferation marker, suggests that 1α(OH)D3 inhibits keratinocyte proliferation, but at the same time the overproduction of keratin 2, a major keratin of the granular cells, indicates that there is an increase in the number of cells in the later stages of differentiation.

ISSN:0302-3427    

DOI:10.1159/000210803

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

This study was designed to investigate the effect of chloroquine (CQ) on the release of preformed and generated mediators from rat serosal mast cells ( > 90% pure). CQ alone (10–1,000 μg/ml) induced the release of preformed mediators, while stimulation with calcium ionophore A23187 of CQ-treated cells resulted in suppressed releases of both preformed and generated (particularly prostaglandin D2) mediators. These effects were calcium-independent and reversible. Whether these results partly explain the efficacy of CQ in the treatment of mast cell-mediated dermatoses remains to be further investigated.

ISSN:0302-3427    

DOI:10.1159/000210804

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

Lonapalene was studied as a topical antipsoriatic agent on the basis of its inhibitory effect on 5-lipoxygenase. We studied the effect of lonapalene on the metabolism of exogenous arachidonic acid in washed platelet suspensions by RP-HPLC. Lonapalene was shown to inhibit platelet cyclooxygenase, with substrate diversion towards 12-HETE production. The pattern of inhibition was similar to that of indometacin, although lonapalene was about 1,000 times weaker. The dual inhibition of lonapalene and concomitant deviation of arachidonic acid metabolism may have potential implications, with regard to therapeutic indications and side effects, which deserve further study.

ISSN:0302-3427    

DOI:10.1159/000210805

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

This study was planned to verify whether different methods for the measurement of skin reactivity, i.e. wheal and flare area, wheal thickness, skin capacitance and transepidermal water loss, were or were not able to discriminate between intradermally injected agonists (histamine and methacholine). For evaluating agonist/antagonist interactions, we adopted a cross-over, double-blind, placebo-controlled study designed to compare the effects of cetirizine and atropine. The intradermal injection of agonists elicited the appearance of wheal and flare reactions and, after histamine, the skinfold thickness was significantly increased. Skin capacitance and transepidermal water loss measurements reflected sweat gland activation after methacholine injection but were, respectively, not or less affected by histamine dry skin prick test or saline; hence, both methods appear very sensitive for in vivo testing of cholinomimetic agents. Cetirizine inhibited all the specific skin modifications induced by histamine challenge, wheals, flares and increased thickness, without affecting the methacholine-induced perspiration. This would further support the H1 specificity of this anti-H1 agent in vivo. However, at the agonist/antagonist ratios tested in view of the safety of the test persons, we were unable to objectivate methacholine blockade by atropine.

ISSN:0302-3427    

DOI:10.1159/000210806

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

The androgen-dependent flank organ of the Golden Syrian hamster has been used as a model for acne and hair growth. 1-cm silastic capsules of testosterone (T) were implanted subcutaneously into female hamsters. Serum levels of T remained relatively constant after 1 week. Maximum growth of the pigmented spot occurred at 4 weeks but regressed by 6 weeks. In contrast, the growth of the pilosebaceous unit continued for 6 weeks. Total sebaceous area and number of sebaceous lobules increased by 3 weeks with a further increase in total area by 6 weeks. The distribution of lobule size shifted to more large lobules. Diameters of hair follicles increased at 3 and 6 weeks with a concomitant recruitment to large follicles. The density of hairs remained constant. The diminution in size of the pigmented spot between 4 and 6 weeks of T stimulation was not related to a reduction in serum T. In fact, there was persistent growth of the sebaceous glands and hair follicles at this time. The measurement of the pigmented spot of the flank organ is not a reliable indicator of the androgen responsiveness of sebaceous glands and/or hair follicles.

ISSN:0302-3427    

DOI:10.1159/000210807

出版商:S. Karger AG    

年代:1989

数据来源: Karger

ISSN:0302-3427    

DOI:10.1159/000210808

出版商:S. Karger AG    

年代:1989

数据来源: Karger

ISSN:0302-3427    

DOI:10.1159/000210809

出版商:S. Karger AG    

年代:1989

数据来源: Karger