Acta dermato-venereologica
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Acta Derm. Venereol. · Jan 2017
Randomized Controlled TrialAntipruritic Effect of Cold-induced and Transient Receptor Potential-agonist-induced Counter-irritation on Histaminergic Itch in Humans.
A frequent empirical observation is that cold-induced counter-irritation may attenuate itch. The aim of this randomized, single-blinded, exploratory study was to evaluate the counter-irritation effects of cold-stimulation and topical application of transient receptor potential TRPA1/M8-agonists (trans-cinnamaldehyde/L-menthol, respectively), on histamine-induced itch, wheals and neurogenic inflammation in 13 healthy volunteers. Histamine 1% was applied to the volar forearms using skin prick-test lancets. ⋯ Cold counter-irritation stimuli from 4°C to 22°C inhibited itch in a stimulus-intensity-dependent manner (p < 0.05) and, to a lesser extent, also wheal reactions and neurogenic inflammation. Chemical "cold-like" counter-irritation with both L-menthol and trans-cinnamaldehyde had antipruritic efficacy similar to doxepin (p < 0.05). Cold-induced counter-irritation had an inhibitory effect on histaminergic itch, suggesting that agonists of cold transduction receptors could be of potential antipruritic value.
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Acta Derm. Venereol. · May 2015
Randomized Controlled Trial Comparative StudyTopical TrkA Kinase Inhibitor CT327 is an Effective, Novel Therapy for the Treatment of Pruritus due to Psoriasis: Results from Experimental Studies, and Efficacy and Safety of CT327 in a Phase 2b Clinical Trial in Patients with Psoriasis.
Pruritus is an important symptom in psoriasis with no targeted treatment. Tropomyosin-receptor kinase A (TrkA) is associated with pruritus and psoriatic plaque formation. We report the efficacy of a TrkA inhibitor, CT327, on pruritus in psoriasis. ⋯ Experiments exploring capsaicin-mediated calcium influx, important in pruritus signalling, were performed in sensory neurons. CT327 inhibited capsaicin responses, indicating action at the nerve growth factor-TrkA-TRPV1 pathway. TrkA is a key target in pruritus, and CT327 has potential to become an effective and safe first-in-class treatment.
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Acta Derm. Venereol. · Jan 2015
Randomized Controlled Trial Comparative StudyGender differences in itch and pain-related sensations provoked by histamine, cowhage and capsaicin.
Cowhage, capsaicin and histamine, all applied via spicules, were used to induce itch and pain-related sensations in 15 male and 15 female subjects. Sensory qualities were assessed by questionnaire; intensities and time courses of the "itching" and "burning" sensation were measured alternately, but continuously on a VAS. In addition, axon reflexes were assessed. ⋯ Female subjects experienced more pain-related sensations (questionnaire), and their ratings leaned more toward burning than those of males. These findings indicate that the mixed itching and burning sensations are differentially processed by both genders. No indications were found for gender specific differential processing in the primary afferents as reflected by nearly identical flare responses.
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Acta Derm. Venereol. · Nov 2012
Randomized Controlled TrialLight fractionation significantly improves the response of superficial basal cell carcinoma to aminolaevulinic acid photodynamic therapy: five-year follow-up of a randomized, prospective trial.
Photodynamic therapy (PDT) using topical porphyrin-precursors is a promising treatment for superficial basal cell carcinoma (sBCC), but it needs further optimization. The aim of this study was to compare 5-year lesion (complete) response rates of sBCC treated with topical aminolaevulinic acid (ALA)-PDT using a single illumination vs. ALA-PDT using a 2-fold illumination scheme. ⋯ Five years after therapy the CR rate after 2-fold illumination was 88%, whereas the CR rate after single illumination was 75%. The CR rate in the third group of lesions, treated with 2-fold illumination was 97% and 88% at 12 months and 5 years after therapy, respectively. Long-term follow-up indicates superior efficacy in sBCC of ALA-PDT with 2-fold illumination compared with ALA-PDT with single illumination.
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Acta Derm. Venereol. · Jan 2008
Randomized Controlled Trial Comparative StudyTargeted broadband ultraviolet b phototherapy produces similar responses to targeted narrowband ultraviolet B phototherapy for vitiligo: a randomized, double-blind study.
Narrowband ultraviolet B (NB-UVB) phototherapy, with a 308-nm xenon chloride excimer laser, and targeted UVB phototherapy have produced encouraging therapeutic results for vitiligo. However, very few studies employing broadband UVB exist. Moreover, there has been no direct comparison study between broadband UVB and NB-UVB for the treatment of vitiligo. The aims of this study were to compare the repigmenting efficacy of targeted broadband UVB phototherapy with that of NB-UVB in an equi-erythemogenic manner. Twenty identical vitiliginous lesions from 10 patients were randomly allocated to receive either targeted broadband UVB or targeted NB-UVB phototherapy. UV fluences were started at 50% of the minimal erythema dose detected within the vitiliginous patches, then increased gradually, in the same manner, to ensure equi-erythemogenic comparison. Treatments were carried out twice weekly for 12 weeks. The results show that grade 1, i.e. 1-25% repigmentation, to grade 2, 26-50% repigmentation, occurred in 6 of 10 subjects. Responses in terms of repigmentation, de-pigmentation, or lack thereof, were similar between lesions receiving broadband and NB-UVB phototherapy. Onset of repigmentation occurred as early as 4 weeks of treatment in most subjects. Treatments were well tolerated, with only minimal erythema and hyperpigmentation. ⋯ The study was carried out in a small number of patients with skin types III, IV and V. The irradiation device was a targeted UVB device and thus the results may not be applicable to other light sources, such as the excimer laser or total-body irradiation cabinets. In conclusion, targeted broadband UVB produces similar clinical responses to targeted NB-UVB in the treatment of the non-segmental type of vitiligo.