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H C Wulf

Publications and source records attributed to H C Wulf.

At least 91 records · Page 5Linked to original sources
PubMed1997

Photodynamic therapy with topical delta-aminolevulinic acid delays UV photocarcinogenesis in hairless mice.

Photodynamic therapy (PDT) with topical application of delta-aminolevulinic acid (ALA) followed by irradiation with visible light (ALA-PDT) is a relatively new and promising experimental treatment of superficial premalignant and malignant skin neoplasms. The purpose of this study was to determine whether ALA-PDT can prevent photocarcinogenesis in hairless mice exposed to solar UV. A total of 140 mice was divided into seven groups of 20 mice each. Group 1: solar-UV exposure. Group 2: solar UV and a cream base+visible light once a week. Group 3: solar UV and ALA-PDT once a week. Group 4: solar UV and ALA-PDT once every second week. Group 5: solar UV and ALA-PDT every fourth week. Group 6: ALA-PDT once a week. Group 7: no treatment. The time to first and to second tumor > or = 1 mm was registered. Predefined endpoints, such as one tumor > or = 4 mm or an area of small confluent tumors on the back of the mice were criteria for withdrawal from the experiment. The time to first and to second tumor was significantly longer in the ALA-PDT-treated mice than in mice only exposed to solar UV and solar-UV/cream base-visible light (P < 0.005). However, we observed an increased death and accident rate in the ALA-PDT-treated groups compared to the groups not treated with ALA-PDT (chi-square test, P = 0.0250). Significantly more ALA-PDT-treated mice were withdrawn because of a tumor > or = 4 mm (P = 0.0005). The UV unexposed mice developed no tumors. Repetitive treatments with ALA-PDT delay photoinduced carcinogenesis in mice.

Administration, Topical↗
PubMed1997

Seasonal variation of skin pigmentation.

We measured skin pigmentation by skin reflectance monthly from May 1992 to April 1993 in 36 healthy Caucasians. Pigmentation was measured at four UV-exposed sites at the forehead, the upper chest, the inside of the upper arm, and at the upper back. The pigmentation and UV sensitivity were simultaneously measured at UV-protected buttock skin. The results showed a considerable seasonal variation for skin pigmentation at the UV-exposed sites. Buttock skin had a pigmentation and UV sensitivity that varied only marginally. We recommend that measurements of genetically controlled skin pigmentation and constitutive UV sensitivity should be performed at UV-unexposed skin on the buttocks, except in persons that expose this site to artificial or natural sunlight.

Adult↗
PubMed1997

The applicability of clinical scoring systems: SCORAD and PASI in psoriasis and atopic dermatitis.

The lack of standard systems for assessment of disease severity poses a problem for the introduction of rational quality control in dermatology. The scoring systems often involve assessment of the same aspects of disease, and it may therefore be conceivable that one system could potentially be applied to routine clinical work and form the basis of disease quantification in dermatology. This study was undertaken to compare PASI (Psoriasis Area and Severity Index) and SCORAD (SCOring index of Atopic Dermatitis) scoring systems, to assess disease severity in patients with atopic dermatitis and psoriasis. Patients with psoriasis (14) and atopic dermatitis (14) were scored with both systems, and correlation coefficients and multiple regression coefficients were calculated. A significant correlation between SCORAD and PASI was found (rs = 0.66). Correlation coefficients were highest (rs = 0.87) when only atopic patients were studied, and lowest (rs = 0.57) when only psoriatic patients were studied. Assessments of area and erythema are suggested as candidates for a generalised scoring systems for dermatological disease. The results suggest that in spite of the overlap between the two score systems, significant diagnosis-specific differences exist, and neither PASI nor SCORAD is an optimal general dermatological scoring system for disease severity. Additional methodological developments are necessary.

Adolescent↗
PubMed1996

Copper vapor laser and photocarcinogenesis in hairless mice.

BACKGROUND AND OBJECTIVE: Port wine stains are commonly located on UV-exposed skin areas. We therefore examined the long-term interaction between UV radiation and copper vapor laser light (578 nm, yellow light) and whether the thermal influence from laser light had a carcinogenic potential itself. STUDY DESIGN/MATERIALS AND METHODS: The study was conducted in lightly pigmented hairless hr/hr C3H/Tif mice and included 8 groups of 17-20 mice. Intensities of 0.5, 1.0, and 1.4 W were used, corresponding to calibrated Hexascan fluences of 15.9, 31.8, and 44.6 J/cm2. Beam diameter was 1 mm and pulse duration 250 msec. UV irradiation of the mice was performed 4 days weekly and started the day after laser treatment. The UV simulated solar ultraviolet radiation can from one Phillips TL 12 and five Bellarium-S SA-1-12 tubes. The daily dose was 1.3 J/cm2, equivalent to 2.1 B-MED. RESULTS: No tumors appeared in groups receiving laser light only. The time to first (P < 0.01), second (P < 0.01), and third (P < 0.02) tumor was significantly delayed in the group treated with 1.4 W before UV irradiation (P < 0.01) compared with those receiving UV radiation only. No significant differences could be demonstrated for the groups treated with 0.5 and 1.0 W. CONCLUSION: One laser treatment with the copper vapor laser did not accelerate UV-induced photocarcinogenesis, and the laser exposure did not have a malignant potential itself.

Animals↗
PubMed1996

Patient-physician consensus on quality of life in dermatology.

This study was undertaken in order to establish the correlation between physician-assessed and patient self-reported quality of life (QOL) when using a proposed Dermatology Life Quality Index (DLQI) in a random sample of 51 dermatological out-patients and in-patients. A substantial correlation was found between physician scores and DLQI (r 2 = 0.306, P < 0.001), suggesting that the DLQI can be used to assess QOL and general morbidity. Comparison of the observed and ideal patient-physician consensus suggests that patients with relatively benign or quiescent disease may over-estimate disease impact, while dermatological patients with more malign or aggressive disease may underestimate it compared with the physician estimate.

Adult↗
PubMed1996

Water protective effect of barrier creams and moisturizing creams: a new in vivo test method.

Frequent exposure to water is an important risk factor for the development of irritant hand eczema. Evaluation of cream efficacy in protecting against water is difficult. A new non-irritant, non-invasive method is introduced, based on evaluation of colour intensities when an aqueous solution of crystal violet is applied to the skin, after pretreatment with different creams. By skin reflectance measurement, differences in colour intensity were objectified. Measurements of transepidermal water loss were also performed, 2 barrier creams and a moisturizer were tested on the dorsal and volar aspects of the hands. One barrier cream contained silicone, the other solid particles. The moisturizer had a high content of lipid. In one experiment, the immediate effect of the creams in protecting against water was evaluated. In a second experiment, the water resistancy of the creams was tested, using a standardized water immersion procedure (4 x 20 min). The barrier cream with particles gave the best immediate protection (dorsal 76%, volar 69%). The moisturizer was intermediately protective (dorsal 57%, volar 34%), while very little protection was found for the silicone-containing cream (dorsal 16%, volar 10%). The water immersion procedure resulted in only minor changes in protection for each cream. When comparing transepidermal water loss in the treated areas with pretreatment values, a reduction was recorded only for the particle-containing barrier cream. The colour method described may be used as a quick and easy test of the protective effect of creams against water.

Adult↗
PubMed1996

The sunscreening effect of urocanic acid.

Urocanic acid (UCA), present in the stratum corneum, is a major absorber of ultraviolet (UV) radiation and, on UV exposure, is induced to isomerize from the naturally occurring trans-isomer to the cis-isomer. Cis-UCA has been shown to have immunosuppressive properties, while trans-UCA may act as a natural sunscreen due to its UV-absorbing properties. The photoprotective capacity of UCA was investigated in this study. Minimal erythema dose (MED) was determined on normal buttock skin in 36 healthy subjects and the concentration of UCA isomers was measured on the skin adjacent to the test site. On the contralateral buttock. MED was determined 20 min after application of trans-UCA 5% in a cream base. The UCA cream gave a sun protection factor of 1.58. The amount of UCA applied was, however, 20-200 times higher than the amount of UCA found in normal skin, making a sunscreening effect of naturally occurring UCA very low. This was further supported, by a lack of correlation between naturally occurring UCA and the UV sensitivity of each subject determined by the MED.

Adolescent↗
PubMed1996

Threshold level for measurement of UV sensitivity: reproducibility of phototest.

The ultraviolet (UV) sensitivity is determined by a phototest where the skin is exposed to well-defined doses of UV radiation and the resulting erythema is graded by visual scoring after 20-24 h. In this study we wanted to estimate the reproducibility of erythema assessment in phototesting. Twenty-one healthy Caucasians with skin types I to IV were phototested on UV un-exposed buttock skin using a xenon lamp solar simulator. Twenty-four hours after UV exposure eight physicians independently graded the erythema reactions two times. Data were analysed using inter- and intra-observer agreement and kappa statistics, which adjusts for agreement that could be caused by chance alone. Observed agreement and kappa statistics were found to decrease with increasing intensity of erythema and to be lower for skin types III and IV compared to skin types I and II. Intra-observer agreement was uniformly better than inter-observer agreement. The difference between observers assessment could be as much as three clinical erythema grades. Physicians's previous experience with phototesting only had a minor influence on agreement. In conclusion, phototesting is based on subjective assessment of erythema and is not as precise and reproducible as expected. Agreement was better for barely perceptible erythema than for erythema with a well-defined border and we therefore recommend that the barely perceptible erythema reaction should be used for measurement of the minimal erythema dose.

Adult↗
PubMed1996

Sun-protection behaviour and self-assessed burning tendency among sunbathers.

A total of 805 sunbathing Caucasians were interviewed about sunprotection behaviour and self-assessed burning tendency. Sixty-seven percent of the interviewed sunbathers used one or more sunscreen factors. Sunscreen-users and nonusers were exposed to the sun 206 min and 197 min (P = 0.186), respectively. The sunscreen users were exposed to a marginally higher UV dose than non-sunscreen users, 4.8 SED versus 4.5 SED (P = 0.0348). The rate of sunscreen users was significantly higher among subjects who stated that they always were sunburnt in the spring when not using a sunscreen than subjects who stated that they never were sunburnt in the spring when not using a sunscreen (P = 0.0001). However, when comparing subjects that always burn in the spring and subjects that never burn in the spring, we found no significant difference between level of the sun-protection factor (P = 0.11) nor the duration of sun exposure (P = 0.967), nor to which UV doses the subjects were exposed (P = 0,562). Furthermore we found that the interviewed sunbathers interpreted to "be sunburnt" as more severe than "to turn red". Public campaigns recommend the use of sun protection cream when sunbathing without using other sun protective strategies; however, the use of sun protection cream is inadequate among sunbathers. More education is required to persuade those with more sun-sensitive skin to use a higher protection-factor, to reduce sun exposure at times when UV radiation is most intense, and to reduce the duration of exposure.

Adult↗
PubMed1996

Skin temperature and phototest evaluation.

The degree of erythema following UV irradiation is known to depend upon skin temperature at the time of UV exposure. We investigated whether changes in skin temperature at the time of erythema assessment influenced the level of erythema. Twenty-two healthy people (mean age 26 years) were irradiated with solar stimulated radiation on previously UV un-exposed buttock skin. The erythematous reactions were evaluated 20-24 h after irradiation by visual scoring and by measurements of skin reflectance and laser Doppler flowmetry. The readings were done at the baseline level at 21 degrees C room temperature where skin temperature was 30.0 +/- 1.7 degrees C and subsequently after skin warming to 37.2 +/- 2.5 degrees C and after cooling to 22.8 +/- 2.6 degrees C. After skin warming, a clinically evaluated erythema grade [0, (+), +, ++, + + +] was scored higher for at least one reaction in 10 of 22 individuals (45%). In the same proportion of subjects, changes to lower erythema grades were detected upon cooling. Skin warming caused an increase in laser Doppler blood flux, but skin cooling did not have a significant effect on cutaneous perfusion. Skin redness measured by skin reflectance was relatively stable during the cooling phase, but a significant increase in skin redness was noted for 0 reaction upon skin warming. For ++ and + + + reactions a small but significance decrease in reflectance was noted. Our results indicate that alterations in skin temperature, especially a temperature increase, modulates the degree of UV-induced erythema moderately. The temperature-dependent changes as an assessment of the (+) reaction are of practical significance, since this reaction is used for the assessment of cutaneous photosensitivity.

Adult↗
PubMed1996

Sun exposure and sunscreen use among sunbathers in Denmark.

Eight hundred and eight sunbathing Danes were interviewed in order to register the duration of sun exposure and sunscreen use. The mean sun exposure time, 203 min, was found to be independent of sex, age and use of sunscreen. Overall, sunscreens were used by 65%, 73% of the females and 52% of the males. The median sun protection factor used by subjects older than 10 years was 5; in the case of children 10 years or younger, it was 12. Eight per cent of the interviewed subjects used more than one factor. Fifty-seven per cent of the sunscreen users applied the sunscreen prior to arriving at the beach. The sun exposure time was not significantly different in the group of subjects using sunscreens, compared to the group of subjects not using sunscreens. This study indicates that sunscreen users may not increase their exposure to the sun.

Adult↗
PubMed1996

Købner reaction induced by photodynamic therapy using delta-aminolevulinic acid. A case report.

We report a case of psoriasis reactivation following photodynamic therapy with delta-aminolevulinic acid. An 84-year-old women received several UVB treatment sessions because of severe psoriasis at her crura in the period from 1960 to 1990. Since then her psoriasis had been inactive. In 1994 she was admitted to our out-patient clinic because of multiple dysplastic lesions as well as multiple carcinomas at her crura. Surgical intervention was impossible and retinoids were not tolerated. She was treated with photodynamic therapy, which provoked a Købner reaction followed by a severe reactivation of the otherwise inactive psoriasis. Whether photodynamic therapy is used for the treatment of multiple dysplastic lesions in a psoriasis patient or for the treatment of psoriasis it seems important to be aware of this adverse effect. This is the first report of Købner reaction following photodynamic therapy.

Aged↗
PubMed1996

Photoprotection in vitiligo and normal skin. A quantitative assessment of the role of stratum corneum, viable epidermis and pigmentation.

Pigmentation, stratum corneum and viable epidermis are considered to be the main factors protecting against ultraviolet radiation. We quantitatively investigated the degree of photoprotection provided by these structures in vitiligo and adjacent normally pigmented skin. In 14 patients 61 MED tests were performed in vitiligo and adjacent normally pigmented skin using a solar simulator. The thickness of stratum corneum and viable epidermis was determined from frozen skin sections, and pigmentation was calculated by measuring skin reflectance at 555 nm and 660 nm. To analyse photoprotection, the UV dose necessary to evoke erythema was regressed against the thickness of stratum corneum and viable epidermis, pigmentation and the erythema grade in the MED test. By analysing regression coefficients we found that stratum corneum was the main photoprotective factor not only in vitiligo but also in normally pigmented skin. The effect of pigmentation in normal skin was slightly less prominent. Stratum corneum was thicker in vitiligo than in normally pigmented skin. However, the photoprotection due to stratum corneum was similar in both groups because significantly less photoprotection was achieved per thickness unit of stratum corneum in vitiligo than in normal skin. Neither in vitiligo nor in normally pigmented skin did the photoprotection depend on viable epidermis. Our data quantitatively document the importance of stratum corneum and pigmentation. Hyperkeratosis in vitiligo offers just as efficient photoprotection as does the normal stratum corneum in pigmented skin.

Adolescent↗
PubMed1996

Skin reflectance-guided laser selections for treatment of decorative tattoos.

BACKGROUND AND DESIGN: A fundamental idea of laser treatment of tattoos is that the wavelength must be well absorbed by the tattoo color. In this study, absorption by different tattoo colors was therefore measured in vivo by skin reflectance to establish optimal laser wavelengths for different tattoo colors. Spectral reflectance by tattooed skin and by normal, uninvolved skin was measured in 10-nm steps in a wavelength range from 300 to 800 nm on eight human volunteers with a total of 13 tattoos, which consisted of 14 different tattoo colors. Wavelength ranges for maximal absorption were established. RESULTS: We found that tattoos absorbed maximally in the following ranges: red tattoos, from 505 to 560 nm (green spectrum); green tattoos, from 630 to 730 nm (red spectrum); and a blue-green tattoo, in two ranges from 400 to 450 nm and from 505 to 560 nm (blue-purple and green spectrums, respectively). Yellow tattoos absorbed maximally from 450 to 510 nm (blue-green spectrum), purple tattoos-absorbed maximally from 550 to 640 nm (green-yellow-orange-red spectrum), blue tattoos absorbed maximally from 620 to 730 nm (red spectrum), and orange tattoos absorbed maximally from 500 to 525 nm (green spectrum). Black and gray absorbed broadly in the visible spectrum, but these colors were most effective from 600 to 800 nm. Optimal and suboptimal laser wavelengths are proposed. CONCLUSIONS: We recommend that wavelength ranges should be established for maximal tattoo absorption before laser treatment of decorative tattoos to select the most optimal laser wavelength present.

Adult↗
PubMed1996

Photodynamic therapy with 5-aminolevulinic acid in the treatment of actinic cheilitis.

Three patients with cheilitis were successfully treated by photodynamic therapy using the topical application of 5-aminolevulinic acid (ALA), followed by irradiation with incoherent visible light. The three patients had had, for several years, disabling lesions on the lower lip, and histopathological examination showed dysplastic lesions without signs of carcinoma. Conventional treatments were ineffective. During photodynamic therapy, all patients reported a burning sensation when irradiated at the ALA treated area, diminishing immediately after removal of the light source, and vanishing within 4 days after treatment. Superficial peeling began 4 days after treatment, and lasted some months. Follow-up, after 6 and 12 months, did not reveal any sign of recurrence.

Aged↗