bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationship between anatomical skin site and response to halcinonide and methyl nicotinate studied by bioengineering techniques
Authors: Clarys P. , Manou I. , Barel A. 
Published: October 2006

Background/aims:Regional differences in percutaneous penetration and skin properties are well documented. However, only a few studies have investigated the relationship between substance penetration and specific skin characteristics in function of the body region. It was our aim to evaluate the physiological effect of topically applied substances in function of skin parameters determined at different body regions.Methods:The characterization of the blanching response to a topically applied corticosteroid and the characterization of the erythema response to topically applied nicotinates were used as two indicators for the percutaneous penetration at selected body regions. Stratum corneum hydration, skin temperature, TEWL, the amount of skin surface lipids and perfusion of the superficial microcirculation were determined at the same body regions.Results:Significant differences in pharmacodynamic response to the corticosteroids and the nicotinates were found in function of the body region. A strong correlation was detected between the parameters characterizing the pharmacodynamic response and the particular skin properties.Conclusion:The regional differences in pharmacological response to topically applied halcinonide and nicotinates may point to a body region dependent bioavailability of the vasoactive substances in the upper skin layers. The significant relationship between the parameters characterizing the physiological skin reaction and the determined skin parameters may be an indication of their involvement in the percutaneous penetration process. These regional differences in pharmacological response seem to be independent of the physicochemical properties of the topically applied substances.
Low‐level luminescence of the human skin
Authors: Cohen S. , Popp F. A. 
Published: October 2006

Background/aims/methods:For the first time systematic measurements of the low‐level luminescence of the human skin (“bi‐ophotons”) have been performed by means of a photon detector device set up in darkness.Results:Several months of daily investigations have shown that body light emission follows definite and well‐known biological rhythms, such as 14 days, 1 month, 3 months, 9 months, and reflects the left‐right symmetry of the body. The results confirm that biophotons are related to physiological functions.Conclusions:This technique provides a new and powerful noninvasive diagnostic method. In particular, skin research and development may use it for testing the influence of different skin treatments.
Objective assessment of the minimal irritant reaction induced by a 70% solution of glycolic acid
Authors: Mantovani Lucia , Belletti Barbara , Seidenari Stefania 
Published: October 2006

Background/aims:Glycolic acid has become a very popular cutaneous improving agent, but, despite its increasing employment, its biophysiological effects on the skin have not been adequately examined. Recently, we described subclinical skin damage induced by a 70% solution of glycolic acid applied on forearm skin by means of non‐invasive measuring techniques. In the present study we instrumentally assessed the cutaneous effects induced by a glycolic acid minimal irritant dose on the volar aspect of the right forearm.Methods:Twenty subjects, seventeen women and three men, aged 16 to 56, were tested with 40 nl of a 70% solution of glycolic acid applied on one volar forearm area until a clincally evident cutaneous reaction occurred. Visual scoring, TEWL measurement, skin colour, capacitance and echographic recordings were performed before the beginning of the experiment and 30 min and 3, 24, 48 and 72 h after glycolic acid removal. The echo‐graphic recordings were carried out using a 20 MHz B scanner (Dermascan C), and then were processed by dedicated software based on segmentation procedures. Two amplitude intervals were selected for the elaboration of the images, the first marking the hyporeflecting areas of the dermis, the second highlighting both the hyperreflecting parts of the epidermis and the lower dermis, separately.Results:Mean application‐time before the appearance of minimal inflammatory skin reactions was 25±7 min. Clinical evaluation was confirmed by the analysis of the colorimetric parameter a*. TEWL and capacitance values showed a marked increase, reaching their maximum at 30 min after solution removal, followed by a progressive decrease. Values of both parameters were statistically significant for up to 48 h. The elaboration of echographic images by a low amplitude interval showed dermal edema more pronounced at 30 min and 24 h, while by highlighting hyperreflecting areas an evident reduction of the entry echo for up to 3 h and a prolonged decrease of the reflectivity of the lower dermis were observable.Conclusion:Our data demonstrate that despite the persistence of higher TEWL values, glycolic acid induced irritation causes a prolonged increase in capacitance that corresponds to modifications in epidermal reflectivity. Epidermal alterations are associated with dermal edema, as evaluated by ultrasound.
Does low power laser light used in laser Doppler systems affect the sensory nerves?
Authors: Wårdell Karin 
Published: October 2006

Background/aims:Many subjects have stated that they can sense the laser light during cutaneous laser Doppler recordings. The aim of the study was therefore to investigate if low power laser light used in laser Doppler systems affects the sensory nerves.Methods:Single point recording as well as imaging was performed with the laser Doppler perfusion imager at the finger pulp, dorsal and ventral side of the hand and the forearm skin in 12 healthy volunteers. The hypothesis “the subject can not sense the laser beam” was tested by double blind random control of the on‐off pattern of the laser light reaching the skin. In total, 96 trials (each including 12 recordings) were performed. Furthermore, it was investigated if the blood flow level was influenced by the subjects “sense” of being measured.Results:The hypothesis was rejected in 92 out of 96 trials. Three of the trials that could not be rejected were recorded from the same subject. In further trials no reproducibility was found. The blood flow level was not influenced by the subjects “sense” of being measured.Conclusions:In general, the laser light used in laser Doppler imaging systems does not influence the sensory nerves. However, it can not be excluded that the laser light used in laser Soppier perfusion imaging (LDPI) affects sensory nerves under unknown circumstances and at specific spots in cutaneous tissue.
Nikolsky's sign: a novel way to evaluate damage at the dermal‐epidermal junction*
Authors: Braue E. H. , Nalls C. R. , Way R. A. , Zallnick J. E. , Rieder R. G. , Mitcheltree L. W. 
Published: October 2006

Background/aims:Sulfur mustard (2,2′‐dichlorodiethyl sulfide, HD) is a potent vesicating (blistering) agent. Cutaneous exposure causes the destruction of basal cells and leads to a separation at the dermal‐epidermal junction. To evaluate the efficacy of candidate antivesicant compounds, suitable animal models are needed. A tape stripping method and the Dermal Torque Meter (DTM) have been used in novel applications to evaluate for the Nikolsky's sign in the hairless guinea pig. The Nikolsky's sign is the separation and loss of the epidermis from the dermis when the skin is pressed with a sliding or twisting motion. The purpose of this study was to find an objective, reproducible, and quantitative method that could be used as an end‐point to evaluate the degree of damage at the dermal‐epidermal junction following cutaneous HD vapor exposure.Methods:Hairless guinea pigs were exposed to saturated HD vapor (1.4 mg/l) for time intervals between 2 and 9 min using 14‐mm vapor cups. At 24 h post‐exposure, both tape stripping (fabric carpet tape) and a DTM were used to produce the Nikolsky's sign in animals under anesthesia. Using the tape stripping method, 15‐mm disks of tape were applied to each skin site. After 5 s the tape was peeled off. The D T M was used to apply a horizontal twisting motion to the skin. The parameters included a 15‐mm center disk, a ring gap of 1 mm, a torque of 30 mNm, and a 5‐s cycle time. A cyanoacrylate adhesive was used to secure the center disk and guard ring to the skin. The loss of the epidermis was determined by visual observation and confirmed by histopathological examination. The standard D T M unit was modified to use multiple center disk/guard ring assemblies so that several sites on each animal could be evaluated at the same time.Results:The mean (±S E M) percent incidence of positive Nikolsky's sign observations using the tape stripping method for HD vapor exposures of 3,5,7, and 9 min was 0,50 (±16), 94 (±6.2), and 100, respectively. The mean (±S E M) percent incidence of positive Nikolsky's sign observations using the D T M method for HD vapor exposures of 2, 3, 4, and 5 min was 0, 25 (±7.1), 91 (±2.9), and 96 (±2.3), respectively.Conclusions:The Nikolsky's sign produced by the tape stripping method and the D T M were useful in evaluating damage at the dermal‐epidermal junction following cutaneous HD vapor exposures. These methods have the potential to replace histopathology as an end‐point for routine screening procedures designed to evaluate the efficacy of antivesicant compounds.
Baseline electrical impedance measurements at various skin sites – related to age and sex
Authors: Nicander Ingrid , Nyren Miruna , Emtestam Lennart , Ollmar Stig 
Published: October 2006

Background/aims:During previous studies on the electrical impedance of the skin, we formulated a set of four physical indices that could be used to distinguish between the cutaneous effects produced by different chemical irritants. We now employ the electrical impedance technique to compare the properties of different anatomical areas of the skin, using the same set of indices.Methods:Investigations were performed on 131 healthy volunteers, who were divided into four groups on the basis of age and sex. Readings of electrical impedance were taken from ten different regions over the body, and transepidermal water loss was measured for comparison.Results:Baseline values of electrical impedance of the skin were shown to vary, depending on the site. Age was also found to exert a major influence, causing an increase in the indices related to magnitude (MIX, RIX, and IMIX) with increasing age, and a decrease in that related to phase (PIX), while sex had only a marginal effect.Conclusions:As with other non‐invasive techniques, baseline characteristics differ from place to place over the body surface, and age is another important determining factor.
Cigarette smoking, cutaneous vasculature and tissue oxygen: an overview
Authors: Leow Yung‐Hian , Maibach Howard I. 
Published: October 2006

Background/aims: This is an overview of the effects of cigarette smoking on the cutaneous blood flow and tissue oxygen.Methods: Published reports on the use of bioengineering methods to evaluate the above are reviewed.Conclusions: There is no one ideal method for studying the effect of cigarette smoking on the cutaneous vasculature. All studies suggest that smoking decreases cutaneous blood flow, but it is not certain if this effect is site‐specific. The tissue oxygen lowering effect of smoking could not be confirmed in all studies.
Quantification of vascular dysregulation in atopic dermatitis using laser Doppler perfusion imaging
Authors: Stäcker Markus , Heese Armin , Hoffmann Klaus , el Gammal Claudia , Altmeyer Peter 
Published: October 2006

Background/aims: The reactivity of cutaneous microcirculation to prostaglandin liberators and histamine has a wide variation in man. Especially patients with atopic dermatitis show frequently altered reactions like the paradox anemic reaction to nicotinic acid esters and the abnormally weak reaction to intracutaneous histamine injection. We wanted to investigate the reproducibility and sensitivity of two‐dimensional laser Doppler perfusion imaging (LDPI) in quantifying these phenomena.Methods: To study the reproducibility of LDPI, we measured the reaction to intracutaneous histamine injection and to application of nicotinic acid ester ointment at different time points and in contralateral body areas in 25 people with normal skin. In a second step, these stimuli were applied in 27 patients with atopic dermatitis and 23 normal controls in order to see whether LDPI is able to detect differences in the cutaneous vascular reaction between both groups.Results: We found an excellent reproducibility of the parameters of LDPI measurements with regard to different locations (0.847≤r≤0.948) and time points (0.686≤r≤0.935). After epicut‐aneous application of nicotinic acid ester, there were significant smaller flow values in the marked center of the reaction in patients with atopic dermatitis compared to the control group. This corresponded to the paradox anemic reaction seen clinically in 15 of 27 patients. After intracutaneous injection of histamine, patients with atopic dermatitis showed significantly higher flow values in the center of reaction than normal controls because whealing was markedly reduced.Conclusions: LDPI proved to be a reproducible and sensitive method for the follow‐up of vascular reactions.
Topographic measurement of skin color by narrow‐band reflectance spectrophotometer and minimal erythema dose (MED) in Koreans
Authors: Park Byung Soon , Youn Jai II 
Published: October 2006

Background/aims: Narrow‐band reflectance spectrophotometer is one of the objective and quantitative devices for measuring the skin colors. There has been some controversy concerning the relationship between the objectively measured skin color and cutaneous responsiveness to ultraviolet radiation, including minimal erythema dose (MED). The aims of this study were to compare the color of Korean brown skin with that of Caucasians by objective measurement with the narrow‐band reflectance spectrophotometer, and to determine whether the skin color has any correlation with MED in Koreans, and demonstrate differences in this correlation according to the anatomical sites.Methods: With narrow‐band reflectance spectrometer, skin colors were measured at 17 body sites of 20 healthy Korean male volunteers after measuring MED for the same subjects.Results: The constitutional skin color, as measured by the melanin index of the nonexposed sites, showed a statistically significant correlation with MED values, whereas the facultative skin color did not. The Korean brown skin showed higher melanin index and lower erythema index compared with that of Caucasians.Conclusions: We confirmed significant differences in the correlation between MED and melanin indices, depending on the anatomic sites. This suggests that selection from various sites, even among the nonexposed sites, is quite important and deserves further evaluation.
Diurnal volume changes of the lower legs in healthy males with a profession that requires standing
Authors: Krijnen R. M. A. , de Boer E. M. , Ader H. J. , Bruynzeel D. P. 
Published: October 2006

Background/aims: The aims of this study are two‐fold: To determine intra‐individual volume changes of the lower legs in the course of a working day in healthy employees with a standing position at work; to relate complaints of the legs in healthy employees with volume changes in the course of the day.Methods: Physical examination and Doppler ultrasound examination were used to exclude the presence of venous disorders. A questionnaire was used to assess complaints of the legs. The lower leg volume was measured with an optical leg volume meter on 2 or 3 days at the beginning and end of a full working day.Results: Included were 197 male workers with a standing profession and no signs of venous insufficiency. The mean volume change of the lower leg was +1.8% for the left leg and +1.6% for the right leg. This volume increase was significant for both legs (P<0.05). A volume [1 volume unit (VU) is approximately 1 ml] increase of over 50 VU was found in 46% of the legs, mean 141 VU. An unchanged volume (‐50 VU to 50 VU) was found VU was found in 18% of the legs, mean ‐138 VU. Sixty‐four percent of the subjects reported subjective complaints of the legs. A tired feeling in the legs, restless legs and a sensation of swelling of the legs were equally present in all three groups of volume change. A statistically significant correlation between pain and a volume decrease was found for the left leg.Conclusions: Diurnal volume changes of the lower legs were distributed as a Gaussian curve. A volume increase was common, but not obligatory. A volume increase of the legs was not associated with complaints of the legs or clinically evident oedema. This suggests that a volume increase can be a physiological phenomenon.
Sodium lauiyl sulphate damaged skin in vivo in man: a water barrier repair model
Authors: Zhai Hongbo , Poblete Nicholas , Maibach Howard I. 
Published: October 2006

Background/aims: Few studies describe enhancing the repair of surfactant‐induced damaged skin. In vivo human studies were conducted to evaluate the efficacy of a topical agent after sodium lauryl sulphate (SLS) induced water barrier disruption.Methods: Occlusive chambers with 1 % SLS were applied to the upper‐backs of volunteers for 24 h, removed and topical agents applied on the SLS‐treated skin sites daily for 5 days. Water barrier restoration was monitored by measuring transepidermal water loss (TEWL).Results: The data were expressed as the percentage of recovery representing normalization of water barrier function. Results showed that a topical agent produced more rapid improvement in barrier function than its placebo vehicle, markedly accelerating repair at 48 h (P<0.01), and persisting throughout the experiment (P<0.05), in comparison with SLS‐control sites.Conclusions: This study suggests that topical agents may accelerate the repair rates of water barrier function in SLS‐treated human skin. This model appears facile and robust for evaluating such repair.
Surface image analysis of nail alterations in juvenile pityriasis rubra pilaris
Authors: Piérard‐Franchimont Claudine , Piérard Gérald E. 
Published: October 2006

Background/aims: Juvenile pityriasis rubra pilaris (PRP) is a rare disease that may alter the nail aspect. Image analysis after nail shadowing was used to quantify trachyonychia associated with juvenile PRRMethods: The mean roughness (Ra) and the mean depth of roughness (Rz) of fingernails were measured three times at 3‐month intervals in nine children suffering from PRR The same measures were taken in 25 age‐matched normal individuals.Results: Both profilometric parameters had higher values in the PRP group than in healthy subjects. The abnormal Ra and Rz values in patients showed variations unrelated to chronobiological cycles.Conclusions: Nail shadowing image analysis is a reliable method to assess inconspicuous to moderate nail surface irregularities. In contrast with some other diseases, the aspect of polymorphic nails in PRP does not seem to be under chronobiological influence.
Skin temperature of UV‐induced erythema correlated to laser Doppler flowmetry and skin reflectance measured redness
Authors: Lock‐Andersen J. , Gniadecka M. , de Fine Olivarius F. , Dahlstrom K. , Wulf H. C. 
Published: October 2006

Background/aims: The sensitivity of human skin to UV radiation is investigated by visual grading of the resulting erythema reactions 24 h after exposure to a series of increasing UV doses. Visual erythema assessment is, however, subjective and depends on pigmentation and redness of the adjacent un‐irradiated skin and can be aided by skin reflectance spectroscopy and laser Doppler blood flow measurements. Erythema is accompanied by a raised skin temperature, and this reaction might be utilised as a simple objective measurement of UV sensitivity.Methods: Sixteen patients with cutaneous malignant melanoma, 16 patients with basal cell carcinoma, and 36 healthy people were phototested with simulated sunlight on previously UV un‐exposed buttock skin. The resulting erythema reactions were graded visually 20‐24 h post‐exposure and measured by skin reflectance spectroscopy and laser Doppler flowmetry, and the surface skin temperature was determined in the erythema reactions and in adjacent un‐irradiated skin by a contact thermometer.Results: Skin surface temperature in UV‐induced erythema reactions was dose dependent, was statistically identical in skin cancer patients and in healthy people, and was age independent. The average temperature increase in barely perceptible erythema was 0.7°C (SD=1.1°C), and in bright red erythema it was 3.5°C (SD=2.0°C). Skin surface temperature increases were correlated to measurements by skin reflectance spectroscopy and by laser Doppler flowmetry.Conclusions: Skin surface temperature changes can be used as a simple objective measurement of UV sensitivity in healthy people and in skin cancer patients and may be particularly useful in heavily pigmented people where visual assessment of erythema is difficult or impossible.
Magnetic resonance chemical shift microimaging of aging human skin in vivo: initial findings
Authors: Wright A. C. , Bohning D. E. , Pecheny A. P. , Spicer K. M. 
Published: October 2006

Background/aims: In recent decades, interest has increased in the chronological and environmental factors governing the aging of skin. Various methods have been used for determining water and lipid content of human skin as a function of subject age. Magnetic resonance chemical shift imaging (CSI) offers a noninvasive technique for observing detailed distributions of water, lipids and other chemicals in the skin, and thus may be useful in dermatogerontology.Methods: Human skin was examined in vivo on nine healthy volunteers, both male and female. Localized 1H spectra of the skin were obtained from voxels 78 μm thick and parallel to the skin surface. Unique water and lipid profiles were observed for different individuals, showing the composition and microstructure of epidermis, dermis and hypodermis in each subject. These allowed the quantification of skin thickness in vivo by the first appearance of triacylglyceride olefinic protons at the dermal‐hy‐podermal junction, or alternatively by the degree of lipid infiltration into dermis.Results: The relative concentration of free water in the skin, normalized to skin thickness, was observed to be slightly greater in older subjects and also in tanned subjects. More significantly, a microstructural feature common to every subject, i.e., the position of a possible capillary plexus in the dermis, showed migration toward the skin surface with advancing age.Conclusions: Such observations are consistent with previous studies of skin aging by other techniques and show promise for CSI in dermatogerontology as a non‐invasive means for determination of skin water in vivo.