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Notes: We present a 35-year-old patient with acquired immunodeficiency syndrome who had demodicidosis on his face, characterized by multiple papules and papulopustules, associated pruritus, numerous mites on skin-surface biopsy and in biopsy specimens, and rapid response to topical treatment with permethrin. It seems likely that Demodex infestation does not manifest unless local or systemic immune function is altered, leading to the proliferation of the organism and subsequent disease.

Notes: Background  Combinations of topical treatments and ultraviolet (UV) B phototherapy for plaque psoriasis may be more beneficial than either type of treatment used alone. Objectives  To determine the efficacy of calcitriol 3 µg g−1 ointment in combination with UVB phototherapy in treating plaque psoriasis. Methods  Calcitriol ointment with UVB was compared with vehicle plus UVB in a randomized, double-blind study in 104 patients. Results  Mean global improvement scores for both groups increased over the 8-week study period; there was a statistically significant difference (P 〈 0·05) in favour of the calcitriol/UVB combination from week 1. At end-point, 45% of the calcitriol/UVB group showed considerable improvement or clearing of psoriasis, compared with 21% of the control group. The superiority of calcitriol plus UVB was also reflected in the global severity and Psoriasis Area and Severity Index (PASI) scores; at end-point the mean percentage decrease in PASI score was 65% for the calcitriol/UVB group and 43% for vehicle/UVB (P = 0·0014). The incidence of skin-related adverse events was low (〈 12%) and similar in the two treatment groups. No clinically significant changes in blood chemistry, in particular calcium levels, occurred. The greater efficacy of combined calcitriol and phototherapy allowed a 34% decrease in total UVB exposure. Conclusions  Calcitriol 3 µg g−1 ointment and UVB phototherapy in combination provides a promising therapy for managing chronic plaque psoriasis.

Notes: Background  Apart from sunscreen lotions, clothing provides protection from acute and chronic sun damage. Therefore, it is very important to know the ultraviolet (UV) protection factor (UPF) of textiles, in particular of lightweight summer clothing. Usually, the UPF of a textile is determined by spectrophotometric assessment of the UV transmission (in vitro method). Objectives  To compare the relationship between in vitro tests and in vivo tests of UPF using solar simulators for determination of the minimal erythema dose (MED), applied to 30 different summer textiles. Methods  Thirty summer textiles were spectrophotometrically assessed, and UPFs were calculated with respect to the International Commission on Illumination (CIE) erythemal action spectrum.1 Based on the in vitro UPFs ‘on skin’ and ‘off skin’, in vivo testing was performed using a solar simulator for the determination of the MEDunprotected and MEDprotected. Results  The UPFs obtained from in vivo‘on skin’ testing were significantly (r = 0·95; P 〈 0·001) lower than the predicted in vitro UPFs. This disparity was also confirmed by chromometric assessment of the MED testing; the erythemal responses measured after textile protection were significantly (P 〈 0·001) higher than those obtained without protection. However, the in vivo‘off skin’ UPFs did not significantly (r = 0·98; P 〉 0·05) differ from the in vitro UPFs; comparison of the chromometrically assessed erythemal responses was also insignificant (P 〉 0·05). Conclusions  The different correlation between in vitro and in vivo measurements of the UPF may be due to the optical–geometrical properties of textiles and the different amount of direct and diffuse radiation passing through the spaces between the yarns. As spectrophotometric measurements of a textile may generally yield lower UPFs than those obtained under average field conditions, the in vitro test method provides ‘safe’ UPF values representing a ‘worst-case scenario’. In contrast to in vitro testing, in vivo methods are much more expensive and time-consuming. Thus, with respect to practicality, spectrophotometric measurements seem to be most suitable for the evaluation of UV protection of textiles.

Notes: In psoriatic lesions. capillaries in the papillary bodies seem elongated and increased in number. Most researchers postulate that there is angiogenesis of intrapapillary capillaries in psoriatic plaques. In this study we will show, by means of computer-aided three-dimensional reconstructions in four patients suffering from chronic plaque-type psoriasis, and in a healthy volunteer. that the elongation and increase of intrapapillary capillaries are not the result of angiogenesis. Our threedimensional reconstructions show that the papillary body of psoriasis contains lymph capillaries besides the blood capillaries. Additionally. an inclusion of two tips of papillary bodies into one papilla at the base of the rete ridges becomes obvious. The vessel of the two tips are connected by a hrizontal vessel. At the level of the horizontal connecting vessel there is the blind begining of a lymphatic vessel. The connecting blood vessel. as well as the lymph capillary. belong to the horizontal subpapillary venous plexus but lie within the papillary body. The three-dimensional reconstructions show that by growing towards the dermis, the rete ridges include the vessels of the horizontal plexus. Surrounded by rete ridges, these vessels appear as intrapapillary capillaries.

Notes: The formation of LTB4 and its ω-oxidation products 20-hydroxy- and 20-carboxy-LTB4 from exogenous [14C] arachidonic acid (AA) by neutrophils from 12 psoriatic patients and 10 healthy controls was investigated. Only a slight difference was detected in the mean amount of [14C]LTB4 produced. In contrast, the amounts of [14C]ω-oxidation products obtained from psoriatic PMN were 2.4-fold higher than the amounts from PMN of healthy controls. We conclude that in vitro, psoriatic PMN synthesize more LTB4 from exogenous AA than do PMN of healthy individuals and due to an efficient ω-oxidation system, the net release of LTB4 in both groups appears to be similar.

Notes: Background  Vitamin B12 is an effective scavenger of nitric oxide (NO). As the experimental application of a NO synthase inhibitor, Nω-nitro-l-arginine, led to a clear decrease in pruritus and erythema in atopic dermatitis, it would be reasonable to assume a comparable effect of vitamin B12.Objectives  The efficacy and tolerability of a new vitamin B12 cream as a possible alternative to current therapies was examined.Methods  A prospective, randomized and placebo-controlled phase III multicentre trial, involving 49 patients was conducted. For the treatment duration of 8 weeks, each patient applied twice daily (in the morning and evening) the vitamin B12-containing active preparation to the affected skin areas of one side of the body and the placebo preparation to the contralateral side according to the randomization scheme.Results  On the body side treated with the vitamin B12 cream, the modified Six Area Six Sign Atopic Dermatitis score dropped to a significantly greater extent than on the placebo-treated body side (for the investigational drug 55·34 ± 5·74 SEM, for placebo 28·87 ± 4·86 SEM, P 〈 0·001). At the conclusion of the study, the investigator and patients awarded mostly a ‘good’ or ‘very good’ rating to the active drug (58% and 59%, respectively) and a ‘moderate’ or ‘poor’ rating to the placebo (89% and 87%, respectively).Conclusions  Topical vitamin B12 is a new therapeutic approach in atopic dermatitis. These results document a significant superiority of vitamin B12 cream in comparison with placebo with regard to the reduction of the extent and severity of atopic dermatitis. Furthermore, the treatment was very well tolerated and involved only very low safety risks for the patients.

Notes: Background  Early detection of melanomas by means of diverse screening campaigns is an important step towards a reduction in mortality. Computer-aided analysis of digital images obtained by dermoscopy has been reported to be an accurate, practical and time-saving tool for the evaluation of pigmented skin lesions (PSLs). A prototype for the computer-aided diagnosis of PSLs using artificial neural networks (NNs) has recently been developed: diagnostic and neural analysis of skin cancer (DANAOS).Objectives  To demonstrate the accuracy of PSL diagnosis by the DANAOS expert system, a multicentre study on a diverse multinational population was conducted.Methods  A calibrated camera system was developed and used to collect images of PSLs in a multicentre study in 13 dermatology centres in nine European countries. The dataset was used to train an NN expert system for the computer-aided diagnosis of melanoma. We analysed different aspects of the data collection and its influence on the performance of the expert system. The NN expert system was trained with a dataset of 2218 dermoscopic images of PSLs.Results  The resulting expert system showed a performance similar to that of dermatologists as published in the literature. The performance depended on the size and quality of the database and its selection.Conclusions  The need for a large database, the usefulness of multicentre data collection, as well as the benefit of a representative collection of cases from clinical practice, were demonstrated in this trial. Images that were difficult to classify using the NN expert system were not identical to those found difficult to classify by clinicians. We suggest therefore that the combination of clinician and computer may potentially increase the accuracy of PSL diagnosis. This may result in improved detection of melanoma and a reduction in unnecessary excisions.

Notes: We studied the respiratory burst activity of peripheral blood monocytes and polymorphonu clear leukocytes (PMN) in eleven patients with psoriasis and eleven healthy controls, using zymosan particles to activate the phagocytes in vitro. The activation of the phagocytes was measured in a luminol-enhanced chemiluminescence (CL) assay. We found a significantly higher respiratory burst activity of both monocytes and PMN in patients with psoriasis compared with the control subjects. The percentages of monocytes in psoriatics did not differ from those of the controls. The higher amount of zymosan-induced CL activity generated in the patient group was unrelated to the age of the individual. Our data indicate increased metabolic reactivity of both monocytes and PMN in psoriasis.