Coexistence and upregulation of three types of opioid receptors, mu, delta and kappa, in human hypertrophic scars
Itch is a significant clinical problem of hypertrophic scar. Recent evidence indicates the possible involvement of opioid receptors (OR) in abnormal cutaneous sensation. The expression of mu (MOR), delta (DOR) and kappa (KOR) OR in normal human skin and symptomatic hypertrophic scars was studied. The results demonstrated the existence and marked upregulation of the three types of OR, MOR, DOR and KOR, in human hypertrophic scars, suggesting the possible link between upregulated OR and local symptoms in hypertrophic scars. Br J Dermatol 2008; 158:713–20.
Demographic and clinical correlates of extent of psoriasis during stable disease and during flares in chronic plaque psoriasis
Two previously observed psoriasis phenotypes, based on area of involvement, are limited extent with occasional widespread flares, common in general practice, and persistent widespread disease, more likely in hospital practice. These have different treatment requirements, but the underlying phenotype may not be evident when a patient presents with widespread involvement. This paper describes readily derived numerical parameters to define these phenotypes which are validated by highly significant demographic and clinical correlations. This approach may have benefit clinically in initial treatment decisions, in investigating genetic and environmental influences on psoriasis severity and in evaluating efficacy in clinical trials. Br J Dermatol 2008; 158:721–26.
Pain during photodynamic therapy is associated with protoporphyrin IX fluorescence and fluence rate
Pain during photodynamic therapy (PDT) is a considerable problem. The objective of this study was to compare pain during PDT using two different fluence rates, and also to evaluate the association between pain and protoporphyrin IX (PpIX) fluorescence, lesion type [acne or actinic keratosis (AK)], lesion preparation and lesion localization. The study showed that pain during illumination was associated with PpIX fluorescence in the treatment area (P=0.0003, R2=0.31). Using a fluence rate of 34 mW cm–2 patients with acne had a pain score of 6 [interquartile range (IQR) 5–7] compared with 8 (IQR 6–10) using a fluence rate of 68 mW cm–2 (P=0.018). After correcting the pain score for PpIX fluorescence no differences in pain scores were found between first and second acne treatment, locations of AK lesions or between the two types of lesions. Br J Dermatol 2008; 158:727–33.
Do sex and site matter? Different age distribution in female and male trunk melanoma
Although the different anatomical distribution of cutaneous malignant melanoma (CMM) by sex is usually attributed to gender-specific patterns of sun exposure, an alternative explanation might lie in gender-specific site susceptibility. Pérez-Gómez et al. compared the age distribution of CMM by site between sexes using a Swedish occupational cohort. Sex differences were particularly striking for trunk melanoma, where incidence rates displayed a steady increase with age in men, but plateaued in women from perimenopausal age. Disparities between sexes could not be attributed to period or cohort effects. These results suggest that a possible interaction between site and sex should be considered in biological research, which points to different site-related aetiological pathways. Br J Dermatol 2008; 158:766–72.
