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It is now generally agreed that solar exposure is a major external factor in the causation of cutaneous melanoma in light skinned populations with red hair and a marked susceptibility to the acute effects of ultraviolet (UV) radiation. In the present study, we investigated the existence of a possible relationship between hair melanin composition and minimal erythema dose (MED), as an indicator of UV sensitivity, in a group of 15 healthy red-haired subjects aged 20-46 years. In spite of comparable skin and hair colour, marked variations were observed in the MED values as well as in the hair melanin composition. Phaeomelanin levels varied in the range 0.026-0.53% w/w and were generally comparable to or higher than eumelanin levels (0.042-0.17% w/w). No significant relationship was found between MED values and phaeomelanin, eumelanin or total melanin (eumelanin plus phaeomelanin) content. Notably, however, a gross positive correlation was found between the eumelanin/phaeomelanin ratio and the MED values. These results would suggest that a high UV sensitivity is associated with high phaeomelanin and low eumelanin levels, and point to the eumelanin/phaeomelanin ratio as a novel chemical parameter that could be used for predicting individuals at high risk for skin cancer and melanoma.

Background: Smoking is known to be a primary cause of chronic harmful effects on the vascular system. It also induces some acute effects on the coronary circulation and on the ophthalmic artery. Objective: The aim of our study was to assess the effect of smoking a single cigarette on cutaneous blood flow in habitual smokers as well as in nonsmokers. Methods: A laser Doppler flowmeter was used to perform measurements of cutaneous microcirculation. Flowmetric data were recorded (i) before smoking, (ii) inhaling from an unlighted cigarette, (iii) during cigarette smoking, (iv) 2 and (v) 5 min after smoking. Results: We could show that smoking a single cigarette acts on the cutaneous microcirculation reducing blood flow in both groups of subjects (38.1% reduction in smokers and 28.1% reduction in nonsmokers; p Conclusion: Smoking a single cigarette decreases the cutaneous blood flow in habitual smoker as well as in nonsmoker subjects. Moreover, the slower recovery phase of smokers suggests that their microcirculation become inured to smoke.

This study was carried out in order to determine whether topically applied khellin followed by UVA exposure is effective for vitiligo treatment. A group of 40 patients with symmetrical vitiligo patches, appbed 5% khellin cream or 3% khellin in 1-methyl-2-pyrrolidinone (PYR) to one side of the body and the vehicle only as placebo to the other side before each session of irradiation. A second group of 32 patients with asymmetrical vitiligo patches applied the vehicle only, an o/w cream or PYR before each session of irradiation. The irradiations were performed every other day. Repigmentation, estimated both clinically and photographically, was similar on vitiligo patches treated with khellin and on those treated only with the vehicle. The mean total dose able to induce initial follicular repigmentation was 550 J/cm2 (range 100-950 J/cm2), administered over 3 months (range 1-5 months). In conclusion, topical application of khellin did not induce repigmentation of vitiligo patches, whose response to therapy seems to be due to UVA irradiation alone. © 1995 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.

Background: Our surroundings are full of non-ionizing electromagnetic radiation (EMR) of different frequency and power. The non-ionizing EMRs emitted by television, computer and cellular phone (CF) sets have been increasing over the past few years. Objective: The aim of our study was to assess the effects of non-ionizing EMRs (frequency 3 × 108 to 3 × 1011 Hz), emitted by CFs, on cutaneous blood flow in healthy volunteers. Methods: Thirty healthy volunteers (14 male and 16 female; age: 18–53 years) entered the study. Measurements of cutaneous blood flow were taken under standard conditions (temperature and humidity), using a laser Doppler He-Ne flowmeter that was applied to the ear skin by an optical fibre probe. Microflow values were recorded without CF contact with the skin (T₀), with the CF turned off but in contact with the ear skin (T1), with CF contact and turned on (T2), with CF contact, turned on and receiving (T3). The microflow values were also recorded backwards: with CF contact and set turned on (T4), with CF contact and turned off (T5), without CF contact (T6). Results: The mean value of basal microflow (T₀), expressed as perfusion units (PU), was 51.26 ± 11.93 PU. During the T1 phase, the microflow increase was 61.38%; in T2 it was 131.74%, in T3 157.67%, in T4 139.21% and in T5 122.90%; in T6, the microflow value was 57.58 ± 10 PU (similar to the basal microflow). Statistically significant cutaneous microflow values (p < 0.050) were observed comparing the T1 to T5 values with basal microflow (T₀). Furthermore, in comparison with T1 values (CF turned off in contact with the ear skin), the T2, T3 and T4 data were statistically significant (T2 vs. T1: t = 7.763 with p < 0.050; T3 vs. T1: t = 9.834 with p < 0.050; T4 vs. T1: t = 8.885 with p < 0.050).

Background: Individual UVB photosensitivity is usually investigated by determining the minimal erythemal dose (MED). Nevertheless, factors such as room light intensity and subjective experience of the observer can influence the erythema perception and, therefore, the MED assessment. Objective: To evaluate the relationship between the clinical and the chromometric and microfiowmetric analyses of the UVB-induced erythema in 2 healthy volunteers. Methods: A bank of 6 fluorescent mercury vapor tubes (Philips TL 12/20 W) was utilized as a source of UVB light. Three skin areas (4 cm2), from the dorsal region of each subject, were irradiated with 3 different UVB doses corresponding to: (1) MED; (2) 0.7 MED, and (3) 1.3 MED. Results: (1) Both microflowmetric and chromometric parameters reached a maximum peak 10–12 h after irradiation and maintained high values also 30 h after irradiation; (2) both microflowmetric and chromometric values were directly related to the UVB doses; (3) in some cases the microflowmetric values started to increase when the chromatic changes were still undetectable. Conclusion: These preliminary data confirm that the visual determination of MED performed 24 h after irradiation is a correct procedure. Nevertheless, the microflowmetric may precede the chromatic changes suggesting that vasodilatation follows irradiation without a latent period.