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Skin Type II (skin + type_ii)
Selected AbstractsUV Erythema Reducing Capacity of Mizolastine Compared to Acetyl-salicylic Acid or both Combined in Comparison to Indomethacin,,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2001Jens-Uwe Grundmann ABSTRACT UV light exerts hazardous effects such as induction of skin cancer and premature skin aging. In this study we evaluated an assumptive anti-inflammatory effect of the nonsedative histamine H1-receptor antagonist, mizolastine, on UV-induced acute sunburn reaction. Therefore, a clinical, randomized, double-blind, four-arm, crossover study was conducted in healthy young female volunteers (skin type II) comparing the UV sensitivity under mizolastine, acetyl-salicylic acid (ASA), indomethacin or a mizolastine/ASA combination. Moreover, HaCaT keratinocytes were incubated with mizolastine under various UV treatment modalities in vitro to study its effect on the release of inflammatory cytokines, i.e. interleukin (IL)-1,, IL-6 and tumor necrosis factor , (TNF-,). All three drugs were effective in suppressing the UVB-, UVA- and combined UVA/UVB-erythema. However, the strongest effects were observed using the combined treatment with both 250 mg ASA and 10 mg mizolastine. An inhibitory effect in vitro of 10 nM mizolastine upon UV-induced cytokine release from HaCaT keratinocytes was observed for IL-1, at 24 h after 10 J/cm2 UVA1, for IL-6 at 48 h after 10 J/cm2 UVA1 and 30 mJ/cm2 UVB, and also for TNF-, at 4 h after 10 J/cm2 UVA, 10 J/cm2 UVA1 and 30 mJ/cm2 UVB, respectively. The combination of mizolastine and ASA can be strongly recommended as a protective measure against UV erythema development with a lower unwanted side effect profile than that of the hitherto treatment modality, i.e. indomethacin. [source] Minimal erythema dose after multiple UV exposures depends on pre-exposure skin pigmentationPHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 4 2004M. Henriksen Background/purpose: Phototherapy consists of multiple ultraviolet (UV) exposures. Most previous studies have focused on erythema following a single UV exposure in fair-skinned persons. Although it is well known that phototherapy lowers the daily UV-threshold dose for erythema in clinical practice, this is insufficiently documented under controlled experimental conditions. The purpose of this study was to quantify the change in the daily threshold for a dose specific erythema grade after 1,4 consecutive daily UV exposures. Methods: Forty-nine healthy volunteers (skin type II,V) with varying pigmentation quantified by skin reflectance. Two UV sources were used: a narrowband UVB (Philips TL01) and a Solar Simulator (Solar Light Co.). Just perceptible erythema after 24 h was chosen as the minimal erythema dose (+); besides + and ++ were assessed. Results: We found a positive and significant exponential relationship between skin pigmentation and UV dose to elicit a specific erythema grade on the back after 1,4 UV exposures. After repetitive UV exposures the UV dose had to be lowered more in dark-skinned persons compared with fair-skinned persons to elicit a certain erythema grade. This applied to both UV sources and all erythema grades. Conclusion: In the dark-skinned persons the daily UV dose after the 4 days UV exposure should be lowered by 40,50% to avoid burns compared with the single UV exposure. For the most fair-skinned persons essentially no reduction in the daily UV dose was needed. Our results indicate that the pre-exposure pigmentation level can guide the UV dosage in phototherapy. [source] Clinical evidence of benefits of a dietary supplement containing probiotic and carotenoids on ultraviolet-induced skin damageBRITISH JOURNAL OF DERMATOLOGY, Issue 3 2010D. Bouilly-Gauthier Summary Background,Lactobacillus johnsonii (La1) has been reported to protect skin immune system homeostasis following ultraviolet (UV) exposure. Objectives, To assess the effects of a dietary supplement (DS) combining La1 and nutritional doses of carotenoids on early UV-induced skin damage. Methods, Three clinical trials (CT1, CT2, CT3) were performed using different UV sources: nonextreme UV with a high UVA irradiance (UV-DL, CT1), extreme simulated solar radiation (UV-SSR, CT2) and natural sunlight (CT3). All three clinical trials were carried out in healthy women over 18 years of age with skin type II,IV. In CT1, early markers of UV-induced skin damage were assessed using histology and immunohistochemistry. In CT2, the minimal erythemal dose (MED) was determined by clinical evaluation and by chromametry. Chromametry was also used to evaluate skin colour. Dermatologists' and subjects' assessments were compiled in CT3. Results, A 10-week DS intake prevented the UV-DL-induced decrease in Langerhans cell density and the increase in factor XIIIa+ type I dermal dendrocytes while it reduced dermal inflammatory cells. Clinical and instrumental MED rose by 20% and 19%, respectively, and skin colour was intensified, as shown by the increase in the ,E* parameter. The efficacy of DS was confirmed by dermatologists and subjects under real conditions of use. Conclusions, Nutritional supplementation combining a specific probiotic (La1) and nutritional doses of carotenoids reduced early UV-induced skin damage caused by simulated or natural sun exposure in a large panel of subjects (n = 139). This latter result might suggest that DS intake could have a beneficial influence on the long-term effects of UV exposure and more specifically on skin photoageing. [source] Plasma levels of opioid peptides after sunbed exposuresBRITISH JOURNAL OF DERMATOLOGY, Issue 6 2002T. Gambichler Summary Background Previous studies have indicated that solar and artificial ultraviolet (UV) radiation have a positive influence on psychological variables such as mood and emotional state. Circulating opioid peptides have been suggested as being important in this effect. Objectives To investigate in a controlled trial the influence of UVA radiation on opioid peptide levels. Methods We determined plasma levels of ,-endorphin immunoreactive material (IRM) and met-enkephalin in UV-exposed ( n = 35) and non-exposed ( n = 9) healthy volunteers. On the first day of the study, blood samples were taken from the volunteers (time A). UVA irradiation was subsequently administered with an air-conditioned tanning device. During the UV exposures the volunteers wore opaque goggles. Twenty minutes after UV exposure, blood samples were collected again (time B). Within the following 3 weeks the volunteers had a series of five UV exposures. On the last day of the study (24 h after the sixth UV exposure) blood samples were collected (time C). The cumulative UVA doses were 96 J cm ,2 for skin type II and 126 J cm ,2 for skin type III. The controls had no UV exposures. Plasma ,-endorphin IRM and met-enkephalin levels were determined using radioimmunoassays. Results At all times of blood collection (A, B, C), there were no significant differences in plasma levels of ,-endorphin IRM and met-enkephalin between UV-exposed and non-exposed volunteers ( P > 0·05). Conclusions UVA irradiation does not significantly elevate plasma levels of ,-endorphin IRM and met-enkephalin. Therefore we suggest that psychological benefits claimed to occur after UV exposure are unlikely to be mediated by the types of circulating opioid peptides measured in this study. [source] Treatment of Striae Rubra and Striae Alba With the 585-nm Pulsed-Dye LaserDERMATOLOGIC SURGERY, Issue 4 2003Gloria P. Jimeénez MD BACKGROUND The treatment of striae distensae has recently been reported with various lasers such as the 585-nm pulsed dye laser. At lower fluences (2.0 to 4.0 J/cm2), this laser has been purported to increase the amount of collagen in the extracellular matrix. OBJECTIVE To determine whether the 585-nm pulsed dye laser is effective in both striae rubra and striae alba after two treatments and, in addition, to determine whether there is a net effect on collagen density in treated samples. METHODS Twenty patients (skin types II to VI) with either striae rubra (9) or striae alba (11) were treated at baseline and at week 6. The total length of the study was 12 weeks. Untreated striae on the same patient were used as control subjects. Striae clinical parameters such as color and area were measured before the first and after the last treatment by an independent examiner using a visual analog scale. A hydroxyproline assay was used to measure collagen changes in two of the striae quantitatively. RESULTS The 585 nm had a moderate beneficial effect in reducing the degree of erythema in striae rubra. There was no apparent clinical change on striae alba. Total collagen per gram of dry weight of sampled tissue increased in striae treated with pulsed dye laser versus control subjects. CONCLUSION We recommend the use of the 585-nm pulsed dye laser for striae rubra in patients skin types II to IV. Extreme caution or avoidance should be observed in pulsed dye laser treatments for patients with phototypes V to VI even with the use of low fluences. Tissue collagen changes measured may be an early change, which precedes significant clinical improvement. [source] Spectrum of idiopathic photodermatoses in a Mediterranean countryINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 6 2003Alexander J. Stratigos md Background ,Idiopathic photodermatoses are considered to be common disorders in the population of northern latitude countries, presumably because of the dominance of more "sun-sensitive" individuals with a light-skinned complexion. The incidence of these disorders in the Mediterranean or tropical countries is often under-appreciated because of the higher degree of perennial presence of sunlight and the prevalence of darker skin-type individuals who are seemingly more resistant to the development of sun sensitivity. Methods ,We performed a retrospective, chart-based review of all patients who were diagnosed with idiopathic photodermatoses at a photodermatology referral center in Athens, Greece, during a period of 10 years. Our aim was to assess the pattern of idiopathic photosensitivity disorders in a Mediterranean country and to determine their epidemiological, clinical, and photobiological profile. Results ,A total of 310 patients were referred to our center with symptoms of photosensitivity. One hundred and forty-six patients (47.0%) were diagnosed with an idiopathic photosensitivity disorder by means of history, clinical examination, biochemical screening, histology, and phototesting. The most prevalent disorder was polymorphous light eruption, which was diagnosed in 95 patients (65.0%) of our cohort. Chronic actinic dermatitis occurred in 15 patients (10.2%), solar urticaria in 26 patients (17.8%), actinic prurigo in three patients (2.0%), hydroa vacciniforme in one patient (0.6%) and juvenile spring eruption in six patients (4.1%). Conclusions ,Compared with the results of other studies, the prevalence of idiopathic photodermatoses appears to have a similar trend to that of higher latitude countries. Distinct features in our series include the higher incidence of idiopathic photosensitivity in patients with a fair-skinned complexion (skin types II,III) and the frequent appearance of photo-induced eruptions during sunny weather breaks in the winter period. [source] Protective effects of a topical antioxidant mixture containing vitamin C, ferulic acid, and phloretin against ultraviolet-induced photodamage in human skinJOURNAL OF COSMETIC DERMATOLOGY, Issue 4 2008Christian Oresajo PhD Summary Background, Ultraviolet (UV) irradiation of the skin leads to acute inflammatory reactions, such as erythema, sunburn, and chronic reactions, including premature skin aging and skin cancer. Aim, In this study, the effects of a topical antioxidant mixture consisting of vitamin C, ferulic acid, and phloretin on attenuating the harmful effects of UV irradiation on normal healthy volunteers were studied using biomarkers of skin damage. Subjects/methods, Ten subjects (age, 18,60 years; Fitzpatrick skin types II and III) were randomized and treated with antioxidant product or vehicle control on the lower back for four consecutive days. On day 3, the minimal erythema dose (MED) was determined for each subject at a different site on the back. On day 4, the two test sites received solar-simulated UV irradiation 1,5× MED at 1× MED intervals. On day 5, digital images were taken, and 4-mm punch biopsies were collected from the two 5× MED test sites and a control site from each subject for morphology and immunohistochemical studies. Results, UV irradiation significantly increased the erythema of human skin in a linear manner from 1× to 5× MED. As early as 24 h after exposure to 5× MEDs of UV irradiation, there were significant increases in sunburn cell formation, thymine dimer formation, matrix metalloproteinase-9 expression, and p53 protein expression. All these changes were attenuated by the antioxidant composition. UV irradiation also suppressed the amount of CD1a-expressing Langerhans cells, indicating immunosuppressive effects of a single 5× MED dose of UV irradiation. Pretreatment of skin with the antioxidant composition blocked this effect. Conclusion, This study confirms the protective role of a unique mixture of antioxidants containing vitamin C, ferulic acid, and phloretin on human skin from the harmful effects of UV irradiation. Phloretin, in addition to being a potent antioxidant, may stabilize and increase the skin availability of topically applied vitamin C and ferulic acid. We propose that antioxidant mixture will complement and synergize with sunscreens in providing photoprotection for human skin. [source] Does the minimal phototoxic dose after 8-methoxypsoralen baths correlate with the individual's skin phototype?PHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 4 2001Ralf Schiener Background/Aims: Up to now no data have been available concerning whether there is a significant correlation between skin phototypes and the minimum phototoxic dose (MPD) after bath water delivery of 8-MOP. Methods: The skin phototype of each of 46 patients was determined based on the individual past history of solar-induced burning and tanning. In addition, the MPD of each patient was assesed after photosensitization with a warm water bath (37 °C, 98.6 °F) containing 1.0 mg/l 8-methoxypsoralen (8-MOP). Statistical analysis was performed using a Mann-Whitney U-test and Spearman rank order correlation. Results: The median MPD in patients with skin phototype II was 2.0 J/cm2 (range ,0.5 to ,3.5) versus 1.5 J/cm2 (range 1.0 to ,3.5) in patients with skin phototype III. There was a considerable overlap between both groups. No significant difference was detected comparing both groups (P=0.7326) and Spearman rank order correlation revealed no correlation between skin phototype and MPD. Conclusion: Erythemal sensitivity in PUVA bath therapy, measured as MPD, is not correlated with sun-reactive skin phototype in skin types II and III. Thus skin phototype is not a suitable indicator for the initial UVA dose in PUVA bath photochemotherapy. [source] | ||||||||||