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Sample records for human skin surface

  1. Life on human surfaces: skin metagenomics.

    Directory of Open Access Journals (Sweden)

    Alban Mathieu

    Full Text Available The human skin microbiome could provide another example, after the gut, of the strong positive or negative impact that human colonizing bacteria can have on health. Deciphering functional diversity and dynamics within human skin microbial communities is critical for understanding their involvement and for developing the appropriate substances for improving or correcting their action. We present a direct PCR-free high throughput sequencing approach to unravel the human skin microbiota specificities through metagenomic dataset analysis and inter-environmental comparison. The approach provided access to the functions carried out by dominant skin colonizing taxa, including Corynebacterium, Staphylococcus and Propionibacterium, revealing their specific capabilities to interact with and exploit compounds from the human skin. These functions, which clearly illustrate the unique life style of the skin microbial communities, stand as invaluable investigation targets for understanding and potentially modifying bacterial interactions with the human host with the objective of increasing health and well being.

  2. Preparation of Artificial Skin that Mimics Human Skin Surface and Mechanical Properties.

    Science.gov (United States)

    Shimizu, Rana; Nonomura, Yoshimune

    2017-12-14

    We have developed an artificial skin that mimics the morphological and mechanical properties of human skin. The artificial skin comprises a polyurethane block possessing a microscopically rough surface. We evaluated the tactile sensations when skin-care cream was applied to the artificial skin. Many subjects perceived smooth, moist, and soft feels during the application process. Cluster analysis showed that these characteristic tactile feels are similar to those when skin-care cream is applied to real human skin. Contact angle analysis showed that an oil droplet spread smoothly on the artificial skin surface, which occurred because there were many grooves several hundred micrometers in width on the skin surface. In addition, when the skin-care cream was applied, the change in frictional force during the dynamic friction process increased. These wetting and frictional properties are important factors controlling the similarity of artificial skin to real human skin.

  3. Molecular cartography of the human skin surface in 3D

    Science.gov (United States)

    Bouslimani, Amina; Porto, Carla; Rath, Christopher M.; Wang, Mingxun; Guo, Yurong; Gonzalez, Antonio; Berg-Lyon, Donna; Ackermann, Gail; Moeller Christensen, Gitte Julie; Nakatsuji, Teruaki; Zhang, Lingjuan; Borkowski, Andrew W.; Meehan, Michael J.; Dorrestein, Kathleen; Gallo, Richard L.; Bandeira, Nuno; Knight, Rob; Alexandrov, Theodore; Dorrestein, Pieter C.

    2015-01-01

    The human skin is an organ with a surface area of 1.5–2 m2 that provides our interface with the environment. The molecular composition of this organ is derived from host cells, microbiota, and external molecules. The chemical makeup of the skin surface is largely undefined. Here we advance the technologies needed to explore the topographical distribution of skin molecules, using 3D mapping of mass spectrometry data and microbial 16S rRNA amplicon sequences. Our 3D maps reveal that the molecular composition of skin has diverse distributions and that the composition is defined not only by skin cells and microbes but also by our daily routines, including the application of hygiene products. The technological development of these maps lays a foundation for studying the spatial relationships of human skin with hygiene, the microbiota, and environment, with potential for developing predictive models of skin phenotypes tailored to individual health. PMID:25825778

  4. Molecular cartography of the human skin surface in 3D.

    Science.gov (United States)

    Bouslimani, Amina; Porto, Carla; Rath, Christopher M; Wang, Mingxun; Guo, Yurong; Gonzalez, Antonio; Berg-Lyon, Donna; Ackermann, Gail; Moeller Christensen, Gitte Julie; Nakatsuji, Teruaki; Zhang, Lingjuan; Borkowski, Andrew W; Meehan, Michael J; Dorrestein, Kathleen; Gallo, Richard L; Bandeira, Nuno; Knight, Rob; Alexandrov, Theodore; Dorrestein, Pieter C

    2015-04-28

    The human skin is an organ with a surface area of 1.5-2 m(2) that provides our interface with the environment. The molecular composition of this organ is derived from host cells, microbiota, and external molecules. The chemical makeup of the skin surface is largely undefined. Here we advance the technologies needed to explore the topographical distribution of skin molecules, using 3D mapping of mass spectrometry data and microbial 16S rRNA amplicon sequences. Our 3D maps reveal that the molecular composition of skin has diverse distributions and that the composition is defined not only by skin cells and microbes but also by our daily routines, including the application of hygiene products. The technological development of these maps lays a foundation for studying the spatial relationships of human skin with hygiene, the microbiota, and environment, with potential for developing predictive models of skin phenotypes tailored to individual health.

  5. Surface free energy of the human skin and its critical surface tension of wetting in the skin/surfactant aqueous solution/air system.

    Science.gov (United States)

    Krawczyk, J

    2015-05-01

    The purpose of these studies was to determine the surface free energy of the human skin and its critical surface tension of wetting in the skin--surfactant aqueous solution--air system in relation to different types of surfactants. The surface free energy of the skin and its components was calculated using the equilibrium advancing contact angle values of water, formamide, and diiodomethane on the forearm skin surface. Next, taking into account the measured values of the contact angle of aqueous solutions of SDDS, CTAB, TX-100 and TX-114 on the skin surface and data of their surface tension, the critical surface tension of the skin wetting was determined. We can classify the skin surface as low-energetic one. The critical surface tension of the skin wetting depends on the type of surfactant. It is possible to determine the critical surface tension of the human skin wetting on the basis of the values of the contact angle of aqueous solutions of surfactants and their surface tension. In this respect, nonionic surfactants seem to be the most appropriate. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Monte Carlo simulation of light reflection from cosmetic powder particles near the human skin surface

    Science.gov (United States)

    Okamoto, Takashi; Kumagawa, Tatsuya; Motoda, Masafumi; Igarashi, Takanori; Nakao, Keisuke

    2013-06-01

    The reflection and scattering properties of light incident on human skin covered with powder particles have been investigated. A three-layer skin structure with a pigmented area is modeled, and the propagation of light in the skin's layers and in a layer of particles near the skin's surface is simulated using the Monte Carlo method. Assuming that only single scattering of light occurs in the powder layer, the simulation results show that the reflection spectra of light from the skin change with the size of powder particles. The color difference between normal and discolored skin is found to decrease considerably when powder particles with a diameter of approximately 0.25 μm are present near the skin's surface. The effects of the medium surrounding the particles, and the influence of the distribution of particle size (polydispersity), are also examined. It is shown that a surrounding medium with a refractive index close to that of the skin substantially suppresses the extreme spectral changes caused by the powder particles covering the skin surface.

  7. Surface topography and contact mechanics of dry and wet human skin

    Directory of Open Access Journals (Sweden)

    Alexander E. Kovalev

    2014-08-01

    Full Text Available The surface topography of the human wrist skin is studied by using optical and atomic force microscopy (AFM methods. By using these techniques the surface roughness power spectrum is obtained. The Persson contact mechanics theory is used to calculate the contact area for different magnifications, for the dry and wet skin. The measured friction coefficient between a glass ball and dry and wet skin can be explained assuming that a frictional shear stress σf ≈ 13 MPa and σf ≈ 5 MPa, respectively, act in the area of real contact during sliding. These frictional shear stresses are typical for sliding on surfaces of elastic bodies. The big increase in friction, which has been observed for glass sliding on wet skin as the skin dries up, can be explained as result of the increase in the contact area arising from the attraction of capillary bridges. Finally, we demonstrated that the real contact area can be properly defined only when a combination of both AFM and optical methods is used for power spectrum calculation.

  8. Human thermal sensation: frequency response to sinusoidal stimuli at the surface of the skin

    DEFF Research Database (Denmark)

    Ring, J.W.; de Dear, Richard; Melikov, Arsen Krikor

    1993-01-01

    . A psychosensory intensity (PSI) model has been developed to relate experimentally derived sensation data to simulated cutaneous thermoreceptor responses to the temperature ramp-plateaux and step stimuli applied to the skin surface by thermodes. From the point of view of signal processing, a natural extension...... function. This function is then compared with the functional form found in two experiments where the stimuli were pulsating airflows of differing frequency. The PSI model seems to simulate well the form of the response of the human skin system to varying temperature changes of a whole range of frequencies...... of this approach is to ask what the response would be to sinusoidally varying stimuli of differing frequencies, or, in other words, what would be the frequency response of this skin system? The purpose of this paper is to extend the PSI model and apply these sinusoids to it and hence find the frequency response...

  9. Analysis of human perception of facial skin radiance by means of image histogram parameters of surface and subsurface reflections from the skin.

    Science.gov (United States)

    Matsubara, Akira; Liang, Zhiwu; Sato, Yuji; Uchikawa, Keiji

    2012-08-01

    The appearance of the skin is the result of complicated light-skin interactions involving surface and subsurface reflections. Radiant skin is a complicated attribute but is important for skin beauty. The aim of the present study was to achieve an understanding of the association between human perceptions of skin radiance and image histogram parameters from technically recorded images of surface and subsurface reflections. Facial images of 45 subjects were evaluated visually by 30 respondents and were also computer analyzed in terms of their image histogram parameters. A partial least squares regression model was created to explain visual perceptions in terms of the image histogram parameters. Visual perceptions of subsurface reflections can be explained in terms of the mean from the subsurface reflection image histogram, and visual perceptions of surface reflections can be explained in terms of the standard deviation (SD) and skewness from the surface reflection image histogram. Skin radiance can be explained in terms of the mean from the subsurface reflection and the SD from the surface reflection. To acquire skin radiance, a surface reflection component that makes the skin look shiny and a subsurface reflection component that is in line with skin fairness are both needed. A balance of these features provides the origin of skin radiance. © 2011 John Wiley & Sons A/S.

  10. Detecting Cannabis Use on the Human Skin Surface via an Electronic Nose System

    Directory of Open Access Journals (Sweden)

    Andreas Voss

    2014-07-01

    Full Text Available The most commonly used drug testing methods are based on the analysis of hair and urine using gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry or immunoassay screening. These methods are time-consuming and partly expensive. One alternative method could be the application of an “electronic nose” (eNose. We have developed an eNose to detect directly on the human skin surface metabolic changes in the human body odor caused by cannabis consumption. Twenty cannabis-smoking and 20 tobacco-smoking volunteers were enrolled in this study. For the sensor signal data processing, two different methods were applied: Principle component analysis (PCA with discriminant analysis, and the method of pattern recognition with subsequent support vector machines (SVM processing. The PCA analysis achieved a correct classification of 70%, whereas the SVM obtained an accuracy of 92.5% (sensitivity 95%, specificity 90% between cannabis-consuming volunteers and tobacco-smoking subjects. This study shows evidence that a low-cost, portable and fast-working eNose system could be useful for health protection, security agencies and for forensic investigations. The ability to analyze human body odor with an eNose opens up a wide field for diagnosing other drugs and also various diseases.

  11. Quantitative model of cellulite: three-dimensional skin surface topography, biophysical characterization, and relationship to human perception.

    Science.gov (United States)

    Smalls, Lola K; Lee, Caroline Y; Whitestone, Jennifer; Kitzmiller, W John; Wickett, R Randall; Visscher, Marty O

    2005-01-01

    Gynoid lipodystrophy (cellulite) is the irregular, dimpled skin surface of the thighs, abdomen, and buttocks in 85% of post-adolescent women. The distinctive surface morphology is believed to result when subcutaneous adipose tissue protrudes into the lower reticular dermis, thereby creating irregularities at the surface. The biomechanical properties of epidermal and dermal tissue may also influence severity. Cellulite-affected thigh sites were measured in 51 females with varying degrees of cellulite, in 11 non-cellulite controls, and in 10 male controls. A non-contact high-resolution three-dimensional laser surface scanner was used to quantify the skin surface morphology and determine specific roughness values. The scans were evaluated by experts and naive judges (n=62). Body composition was evaluated via dual-energy x-ray absorptiometry; dermal thickness and the dermal-subcutaneous junction were evaluated via high-resolution 3D ultrasound and surface photography under compression. Biomechanical properties were also measured. The roughness parameters Svm (mean depth of the lowest valleys) and Sdr (ratio between the roughness surface area and the area of the xy plane) were highly correlated to the expert image grades and, therefore, designated as the quantitative measures of cellulite severity. The strength of the correlations among naive grades, expert grades, and roughness values confirmed that the data quantitatively evaluate the human perception of cellulite. Cellulite severity was correlated to BMI, thigh circumference, percent thigh fat, architecture of the dermal-subcutaneous border (ultrasound surface area, red-band SD from compressed images), compliance, and stiffness (negative correlation). Cellulite severity was predicted by the percent fat and the area of the dermal-subcutaneous border. The biomechanical properties did not significantly contribute to the prediction. Comparison of the parameters for females and males further suggest that percent thigh fat

  12. Photo-oxidation products of skin surface squalene mediate metabolic and inflammatory responses to solar UV in human keratinocytes.

    Directory of Open Access Journals (Sweden)

    Vladimir Kostyuk

    Full Text Available The study aimed to identify endogenous lipid mediators of metabolic and inflammatory responses of human keratinocytes to solar UV irradiation. Physiologically relevant doses of solar simulated UVA+UVB were applied to human skin surface lipids (SSL or to primary cultures of normal human epidermal keratinocytes (NHEK. The decay of photo-sensitive lipid-soluble components, alpha-tocopherol, squalene (Sq, and cholesterol in SSL was analysed and products of squalene photo-oxidation (SqPx were quantitatively isolated from irradiated SSL. When administered directly to NHEK, low-dose solar UVA+UVB induced time-dependent inflammatory and metabolic responses. To mimic UVA+UVB action, NHEK were exposed to intact or photo-oxidised SSL, Sq or SqPx, 4-hydroxy-2-nonenal (4-HNE, and the product of tryptophan photo-oxidation 6-formylindolo[3,2-b]carbazole (FICZ. FICZ activated exclusively metabolic responses characteristic for UV, i.e. the aryl hydrocarbon receptor (AhR machinery and downstream CYP1A1/CYP1B1 gene expression, while 4-HNE slightly stimulated inflammatory UV markers IL-6, COX-2, and iNOS genes. On contrast, SqPx induced the majority of metabolic and inflammatory responses characteristic for UVA+UVB, acting via AhR, EGFR, and G-protein-coupled arachidonic acid receptor (G2A.Our findings indicate that Sq could be a primary sensor of solar UV irradiation in human SSL, and products of its photo-oxidation mediate/induce metabolic and inflammatory responses of keratinocytes to UVA+UVB, which could be relevant for skin inflammation in the sun-exposed oily skin.

  13. The role of the skin microrelief in the contact behaviour of human skin: contact between the human finger and regular surface textures

    NARCIS (Netherlands)

    van Kuilenburg, Julien; Masen, Marc Arthur; van der Heide, Emile

    2013-01-01

    The friction behaviour of the human fingerpad as a function of asperity geometry was investigated experimentally. Surface textures consisting of evenly distributed spherically tipped asperities were used for in vivo testing. Using analytical expressions, a multi-scale model was developed to explain

  14. Strontium hexaferrite nanomagnets suspended in a cosmetic preparation: a convenient tool to evaluate the biological effects of surface magnetism on human skin.

    Science.gov (United States)

    Zioni, T; Perkas, N; Wolfus, Y; Soroka, Y; Popov, I; Oron, M; Perelshtein, I; Bruckental, Y; Brégégère, F M; Ma'or, Z; Gedanken, A; Yeshurun, Y; Neuman, R; Milner, Y

    2010-08-01

    Magnetic therapy has been popular for ages, but its therapeutic abilities remain to be demonstrated. We aimed to develop a homogeneous, stable dispersion of magnetic nanoparticles in a skin-care preparation, as a tool to analyze the biological and physiological effects of superficial magnetism in skin. SrFe(12)O(19) nanoparticles were generated by ultrasound, dispersed in glycerol, stabilized in Dermud cream and permanently magnetized. The magnetic cream was applied on the epidermis of human skin organ cultures. The effects on UV-induced cell toxicity, apoptosis and inflammatory cytokine expression were analyzed. A clinical test was performed to check skin moisturization. Nanomagnets were found to be homogenously and stably dispersed. After magnetization, the preparation generated a magnetic field of 1-2 G. Upon cream application, no cytotoxicity and no impairment of cellular vitality were found after 24 and 48 h, respectively. The anti-apoptotic and anti-inflammatory properties of Dermud were not modified, but its long-term effect on moisturization in vivo was slightly increased. Nanomagnetic Dermud cream can be used as a tool to analyze the biological effects of nanomagnets dispersed on the skin surface at the cellular and molecular levels, thus allowing to explore the possible therapeutic uses of superficial magnetism for skin care.

  15. Meshing skin surfaces with certified topology

    NARCIS (Netherlands)

    Kruithof, N.G.H.; Vegter, G.

    2005-01-01

    Skin surfaces are used for the modeling and visualization of molecules. They form a class of tangent continuous surfaces defined in terms of a set of balls (the atoms of the molecule) and a shrink factor More recently, skin surfaces have been used to approximate arbitrary surfaces. We present an

  16. In vivo MR imaging of the human skin at subnanoliter resolution using a superconducting surface coil at 1.5 Tesla.

    Science.gov (United States)

    Laistler, Elmar; Poirier-Quinot, Marie; Lambert, Simon A; Dubuisson, Rose-Marie; Girard, Olivier M; Moser, Ewald; Darrasse, Luc; Ginefri, Jean-Christophe

    2015-02-01

    To demonstrate the feasibility of a highly sensitive superconducting surface coil for microscopic MRI of the human skin in vivo in a clinical 1.5 Tesla (T) scanner. A 12.4-mm high-temperature superconducting coil was used at 1.5T for phantom and in vivo skin imaging. Images were inspected to identify fine anatomical skin structures. Signal-to-noise ratio (SNR) improvement by the high-temperature superconducting (HTS) coil, as compared to a commercial MR microscopy coil was quantified from phantom imaging; the gain over a geometrically identical coil made from copper (cooled or not) was theoretically deduced. Noise sources were identified to evaluate the potential of HTS coils for future studies. In vivo skin images with isotropic 80 μm resolution were demonstrated revealing fine anatomical structures. The HTS coil improved SNR by a factor 32 over the reference coil in a nonloading phantom. For calf imaging, SNR gains of 380% and 30% can be expected over an identical copper coil at room temperature and 77 K, respectively. The high sensitivity of HTS coils allows for microscopic imaging of the skin at 1.5T and could serve as a tool for dermatology in a clinical setting. © 2013 Wiley Periodicals, Inc.

  17. [The clinical use of cryopreserved human skin allografts for transplantation].

    Science.gov (United States)

    Martínez-Flores, Francisco; Chacón-Gómez, María; Madinaveitia-Villanueva, Juan Antonio; Barrera-Lopez, Araceli; Aguirre-Cruz, Lucinda; Querevalu-Murillo, Walter

    2015-01-01

    The biological recovery of human skin allografts is the gold standard for preservation in Skin Banks. However, there is no worldwide consensus about specific allocation criteria for preserved human skin allografts with living cells. A report is presented on the results of 5 years of experience of using human skin allografts in burned patient in the Skin and Tissue Bank at the "Instituto Nacional de Rehabilitacion" The human skin allografts were obtained from multi-organ donors. processed and preserved at -80 °C for 12 months. Allocation criteria were performed according to blood type match, clinical history, and burned body surface. Up to now, the Skin and Tissue Bank at 'Instituto Nacional de Rehabilitacion" has processed and recovered 125,000 cm(2) of human skin allografts. It has performed 34 surgical implants on 21 burned patients. The average of burn body surface was 59.2%. More than two-thirds (67.7%) of recipients of skin allografts were matched of the same to type blood of the donor, and 66.6% survived after 126 days hospital stay. It is proposed to consider recipient's blood group as allocation criteria to assign tissue; and use human skin allografts on patiens affected with burns over 30% of body surface (according the "rule of the 9"). Copyright © 2015 Academia Mexicana de Cirugía A.C. Published by Masson Doyma México S.A. All rights reserved.

  18. Effects of contact allergens on human Langerhans cells in skin organ culture: migration, modulation of cell surface molecules, and early expression of interleukin-1 beta protein

    NARCIS (Netherlands)

    Rambukkana, A.; Pistoor, F. H.; Bos, J. D.; Kapsenberg, M. L.; Das, P. K.

    1996-01-01

    Epidermal Langerhans cells (LC) and cytokines play a critical role in the initiation phase of contact hypersensitivity reactions in the skin. Most of the studies of these aspects have been performed in animal models and relatively little is known about the human system. Short-term human skin organ

  19. Skin and the non-human human

    DEFF Research Database (Denmark)

    Rösing, Lilian Munk

    2013-01-01

    ) article 'Visualizing the mind: Looking at Titian's Flaying of Marsyas', addressing features of the painting not commented on by Hart, and supplementing Hart's (Kleinian) theoretical frame by involving Didier Anzieu's 'skin ego', Slavoj Zizek's concept of the 'non-human', Giorgio Agamben's term...

  20. The Microbiota of the Human Skin.

    Science.gov (United States)

    Egert, Markus; Simmering, Rainer

    2016-01-01

    The aim of this chapter is to sum up important progress in the field of human skin microbiota research that was achieved over the last years.The human skin is one of the largest and most versatile organs of the human body. Owing to its function as a protective interface between the largely sterile interior of the human body and the highly microbially contaminated outer environment, it is densely colonized with a diverse and active microbiota. This skin microbiota is of high importance for human health and well-being. It is implicated in several severe skin diseases and plays a major role in wound infections. Many less severe, but negatively perceived cosmetic skin phenomena are linked with skin microbes, too. In addition, skin microorganisms, in particular on the human hands, are crucial for the field of hygiene research. Notably, apart from being only a potential source of disease and contamination, the skin microbiota also contributes to the protective functions of the human skin in many ways. Finally, the analysis of structure and function of the human skin microbiota is interesting from a basic, evolutionary perspective on human microbe interactions.Key questions in the field of skin microbiota research deal with (a) a deeper understanding of the structure (species inventory) and function (physiology) of the healthy human skin microbiota in space and time, (b) the distinction of resident and transient skin microbiota members, (c) the distinction of beneficial skin microorganisms from microorganisms or communities with an adverse or sickening effect on their hosts, (d) factors shaping the skin microbiota and its functional role in health and disease, (e) strategies to manipulate the skin microbiota for therapeutic reasons.

  1. Human papillomaviruses and skin cancer.

    Science.gov (United States)

    Smola, Sigrun

    2014-01-01

    Human papillomaviruses (HPVs) infect squamous epithelia and can induce hyperproliferative lesions. More than 120 different HPV types have been characterized and classified into five different genera. While mucosal high-risk HPVs have a well-established causal role in anogenital carcinogenesis, the biology of cutaneous HPVs is less well understood. The clinical relevance of genus beta-PV infection has clearly been demonstrated in patients suffering from epidermodysplasia verruciformis (EV), a rare inherited disease associated with ahigh rate of skin cancer. In the normal population genus beta-PV are suspected to have an etiologic role in skin carcinogenesis as well but this is still controversially discussed. Their oncogenic potency has been investigated in mouse models and in vitro. In 2009, the International Agency for Research on Cancer (IARC) classified the genus beta HPV types 5 and 8 as "possible carcinogenic" biological agents (group 2B) in EV disease. This chapter will give an overview on the knowns and unknowns of infections with genus beta-PV and discuss their potential impact on skin carcinogenesis in the general population.

  2. The virtual human face: superimposing the simultaneously captured 3D photorealistic skin surface of the face on the untextured skin image of the CBCT scan.

    Science.gov (United States)

    Naudi, K B; Benramadan, R; Brocklebank, L; Ju, X; Khambay, B; Ayoub, A

    2013-03-01

    The aim of this study was to evaluate the impact of simultaneous capture of the three-dimensional (3D) surface of the face and cone beam computed tomography (CBCT) scan of the skull on the accuracy of their registration and superimposition. 3D facial images were acquired in 14 patients using the Di3d (Dimensional Imaging, UK) imaging system and i-CAT CBCT scanner. One stereophotogrammetry image was captured at the same time as the CBCT and another 1h later. The two stereophotographs were individually superimposed over the CBCT using VRmesh. Seven patches were isolated on the final merged surfaces. For the whole face and each individual patch: maximum and minimum range of deviation between surfaces; absolute average distance between surfaces; and standard deviation for the 90th percentile of the distance errors were calculated. The superimposition errors of the whole face for both captures revealed statistically significant differences (P=0.00081). The absolute average distances in both separate and simultaneous captures were 0.47 and 0.27mm, respectively. The level of superimposition accuracy in patches from separate captures was 0.3-0.9mm, while that of simultaneous captures was 0.4mm. Simultaneous capture of Di3d and CBCT images significantly improved the accuracy of superimposition of these image modalities. Copyright © 2012 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  3. In vivo human skin autofluorescence: color perception

    Science.gov (United States)

    Utz, Sergei R.; Knuschke, Peter; Mavlyutov, Albert H.; Pilipenko, Helena A.; Sinichkin, Yurii P.

    1996-12-01

    The most frequently used techniques in the human skin diagnostics are reflectance and fluorescence spectroscopy. Technique of chromametry is based on color perception of the reflected from the skin white light. In CIE1976 (L*a*b*) color space the quantity estimation of color-difference between different states of the human skin have been defined by changes in parameters of brightness, hue and chroma of reflected light. This report focuses on the use of the perception of the color difference between autofluorescence of the human skin under different conditions for the purpose of skin diagnostics.

  4. Human reconstructed skin xenografts on mice to model skin physiology.

    Science.gov (United States)

    Salgado, Giorgiana; Ng, Yi Zhen; Koh, Li Fang; Goh, Christabelle S M; Common, John E

    Xenograft models to study skin physiology have been popular for scientific use since the 1970s, with various developments and improvements to the techniques over the decades. Xenograft models are particularly useful and sought after due to the lack of clinically relevant animal models in predicting drug effectiveness in humans. Such predictions could in turn boost the process of drug discovery, since novel drug compounds have an estimated 8% chance of FDA approval despite years of rigorous preclinical testing and evaluation, albeit mostly in non-human models. In the case of skin research, the mouse persists as the most popular animal model of choice, despite its well-known anatomical differences with human skin. Differences in skin biology are especially evident when trying to dissect more complex skin conditions, such as psoriasis and eczema, where interactions between the immune system, epidermis and the environment likely occur. While the use of animal models are still considered the gold standard for systemic toxicity studies under controlled environments, there are now alternative models that have been approved for certain applications. To overcome the biological limitations of the mouse model, research efforts have also focused on "humanizing" the mice model to better recapitulate human skin physiology. In this review, we outline the different approaches undertaken thus far to study skin biology using human tissue xenografts in mice and the technical challenges involved. We also describe more recent developments to generate humanized multi-tissue compartment mice that carry both a functioning human immune system and skin xenografts. Such composite animal models provide promising opportunities to study drugs, disease and differentiation with greater clinical relevance. Copyright © 2017 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

  5. Surface pH of Normal Skin

    Directory of Open Access Journals (Sweden)

    A B Gupta

    1987-01-01

    Full Text Available The skin furface pH of 55 brown-skinned individuals (Indians comprising of 30 males and 25 females in the age range 12-58 years has been measured at the forehead (FH and the back of the wrist (BW. The mean values of skin pH at FH and BW are 5.51 + 0.32 and 5.56 + 0.40 respectively for male. The corresponding female values are 5.73 + 0.032 and 5.84 + 0.28 statistical analysis of the data shows that (i the dependence of skin surface pH on age is not significant, (ii the male skin is slightly, but significantly more acidic than the female one, (iii the mean values of skin pH at forehead and at back of the wrist do not differ significantly for male ; the difference however is significant for female at 5% level, (iv there exists a significant positive correlation ( r=0.77 for male and r + 0.71 for female between the pH's of the forehead (x2 and the back of the wrist (z3. The regression equation of x2 on x3 are: x2= 2.13+0.61 for male and x2=1.05 + 0.80x3 for female.

  6. Dissolution of materials in artificial skin surface film liquids.

    Science.gov (United States)

    Stefaniak, Aleksandr B; Harvey, Christopher J

    2006-12-01

    The dissolution of chemical constituents from jewelry, textiles, cosmetics, drugs, industrial chemicals, and particles in direct and prolonged contact with human skin is often assessed in vitro using artificial skin surface film liquids (SSFL). To provide meaningful results, the composition of artificial SSFL should accurately mimic human sweat and sebum, and the conditions of the in vitro test system should accurately reflect in vivo skin conditions. We summarized the reported composition of human SSFL and compared it to 45 different formulations of artificial sweat and 18 formulations of artificial sebum (studies published from 1940 to 2005). Conditions of in vitro dissolution test systems were reviewed and compared to in vivo skin conditions. The concentrations of individual constituents and pH of artificial sweat and concentrations of artificial sebum constituents are not always within ranges reported for human SSFL. Nearly all artificial SSFL lack many of the constituents in human SSFL. To develop a comprehensive model SSFL, we propose a standard SSFL, modified from the two best published sweat and sebum formulations. Little is known concerning the influence of test system conditions on dissolution, including SSFL temperature, container material composition, agitation, and physicochemical properties of the test article on dissolution. Thus, both a need and an opportunity exist for standardizing the composition of artificial SSFL and in vitro dissolution test methodologies. To standardize in vitro dissolution test systems, we recommend: maintaining artificial SSFL at a biologically relevant temperature appropriate to the human activity being modeled, carefully selecting test and sample storage containers to avoid bias in dissolution measurements, accounting for friction between a test article and skin in a biologically plausible manner, and physicochemical characterization of the test article or material to better understand mechanisms of dissolution and

  7. Neurogenic inflammation in human and rodent skin

    DEFF Research Database (Denmark)

    Schmelz, M; Petersen, Lars Jelstrup

    2001-01-01

    The combination of vasodilation and protein extravasation following activation of nociceptors has been termed "neurogenic inflammation." In contrast to rodents, no neurogenic protein extravasation can be elicited in healthy human skin. Dermal microdialysis has considerably increased our knowledge...... about neurogenic inflammation in human skin, including the involvement of mast cells....

  8. Harmonics optical biopsy of human skin

    Science.gov (United States)

    Tai, Shih-Peng; Tsai, Tsung-Han; Chu, Shi-Wei; Lee, Wen-Jeng; Liao, Yi-Hua; Huang, Hsin-Yi; Sun, Chi-Kuang

    2005-04-01

    Traditional biopsy requires the removal, fixation, and staining of tissues from the human body. Its procedure is invasive and painful. Therefore, a novel method of optical biopsy is desired which can perform in vivo examination and is noninvasive, highly penetrative, with no energy deposition and damage, without invasive pharmaceutical injection, and with three-dimensional (3D) imaging capability and sub-micron spatial resolution. Two-photon fluorescence microscopy (TPFM) is previously applied for biopsy of skin due to its high lateral resolution, low out-of-focus damage, and intrinsic 3D section capability. However, for future clinical applications without surgery, current 700-850 nm based laser scanning technology still presents several limitations including low penetration depth, in-focus cell damages, multi-photon phototoxicity due to high optical intensity in the 800 nm wavelength region, and toxicity if exogenous fluorescence markers were required. Here we demonstrate a novel noninvasive optical biopsy method called harmonics optical biopsy (HOB), which combines both second harmonic generation imaging and third harmonic generation imaging. Due to virtual transition nature of harmonic generations and based on light sources with an optical wavelength located around the biological penetration window (~1300nm), our HOB can serve as a truly non-invasive biopsy tool with sub-micron three-dimensional spatial resolution without any energy deposition and exogenous contrast agents. From preliminary experiment result, our HOB can reconstruct 3D cellular and subcellular images from skin surface through dermis. Besides, by utilizing backward propagating detection geometry, we will show that this technique is ideal for non-invasive clinical biopsy of human skin diseases and even useful for the early diagnosis of skin cancer symptom such as the angiogenesis.

  9. Exposure to Phthalate Emitted from Vinyl Flooring and Sorbed to Interior Surfaces, Dust, Airborne Particles and Human Skin

    Science.gov (United States)

    There is an urgent need to characterize potential risk to human health and the environment that arises from the manufacture and use of tens of thousands of chemicals. Computational tools and approaches for characterizing and prioritizing exposure are required: to provide input f...

  10. In-vivo spectroscopic ellipsometry measurements of human skin

    Science.gov (United States)

    Chan, Danny; Schulz, Benjamin; Ruebhausen, Michael

    2004-03-01

    Human skin can be described as a layered biological tissue. Knowledge of the behaviour of the optical properties of skin across the layers is limited. We describe an ellipsometric setup for spectrally resolved in-vivo measurements of human skin and show measurements of the complex refractive index N=n+ik of the finger of several volunteers over a range from 330 to 780 nm. A tapestripping study of human skin reveals the profile of the complex refractive index extracted from a simple bulk model over the stratum corneum. Fits of the evolution of n and k to an exponential function show that after approximately five strips a steady state is reached. A refined model applying an effective medium approximation accounting for surface roughness describes the development of the ellipsometric parameter Ψ in terms of the skin's increased water content with deeper depth of the measured layer.

  11. The immunology of the porcine skin and its value as a model for human skin.

    Science.gov (United States)

    Summerfield, Artur; Meurens, François; Ricklin, Meret E

    2015-07-01

    The porcine skin has striking similarities to the human skin in terms of general structure, thickness, hair follicle content, pigmentation, collagen and lipid composition. This has been the basis for numerous studies using the pig as a model for wound healing, transdermal delivery, dermal toxicology, radiation and UVB effects. Considering that the skin also represents an immune organ of utmost importance for health, immune cells present in the skin of the pig will be reviewed. The focus of this review is on dendritic cells, which play a central role in the skin immune system as they serve as sentinels in the skin, which offers a large surface area exposed to the environment. Based on a literature review and original data we propose a classification of porcine dendritic cell subsets in the skin corresponding to the subsets described in the human skin. The equivalent of the human CD141(+) DC subset is CD1a(-)CD4(-)CD172a(-)CADM1(high), that of the CD1c(+) subset is CD1a(+)CD4(-)CD172a(+)CADM1(+/low), and porcine plasmacytoid dendritic cells are CD1a(-)CD4(+)CD172a(+)CADM1(-). CD209 and CD14 could represent markers of inflammatory monocyte-derived cells, either dendritic cells or macrophages. Future studies for example using transriptomic analysis of sorted populations are required to confirm the identity of these cells. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Photoprotection of human skin beyond ultraviolet radiation.

    Science.gov (United States)

    Grether-Beck, Susanne; Marini, Alessandra; Jaenicke, Thomas; Krutmann, Jean

    2014-01-01

    Photoprotection of human skin by means of sunscreens or daily skin-care products is traditionally centered around the prevention of acute (e.g. sunburn) and chronic (e.g. skin cancer and photoaging) skin damage that may result from exposure to ultraviolet rays (UVB and UVA). Within the last decade, however, it has been appreciated that wavelengths beyond the ultraviolet spectrum, in particular visible light and infrared radiation, contribute to skin damage in general and photoaging of human skin in particular. As a consequence, attempts have been made to develop skin care/sunscreen products that not only protect against UVB or UVA radiation but provide photoprotection against visible light and infrared radiation as well. In this article, we will briefly review the current knowledge about the mechanisms responsible for visible light/infrared radiation-induced skin damage and then, based on this information, discuss strategies that have been successfully used or may be employed in the future to achieve photoprotection of human skin beyond ultraviolet radiation. In this regard we will particularly focus on the use of topical antioxidants and the challenges that result from the task of showing their efficacy. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Water vapour loss measurements on human skin.

    NARCIS (Netherlands)

    Valk, Petrus Gerardus Maria van der

    1984-01-01

    In this thesis, the results of a series of investigations into the barrier function of human skin are presented. In these investigations, the barrier function was assessed by water vapour loss measurements of the skin using a method based on gradient estimation.... Zie: Summary and conclusions

  14. Deposition of contaminant aerosol on human skin

    DEFF Research Database (Denmark)

    Andersson, Kasper Grann; Roed, Jørn; Byrne, M.A.

    2006-01-01

    Over recent years, it has been established that deposition of various types of pollutant aerosols (e.g., radioactive) on human skin can have serious deleterious effects on health. However. only few investigations in the past have been devoted to measurement of deposition velocities on skin...

  15. Black and white human skin differences

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Maibach, H I

    1979-01-01

    This review of black and white human skin differences emphasizes the alleged importance of factors other than the obvious, i.e., skin color. Physicochemical differences and differences in susceptibility to irritants and allergens suggest a more resistant black than white skin. Differences appear...... to exist in the frequency of which several skin diseases occur among blacks and whites. A striking feature in this literature is the disagreement between authors. Common for much of this information is difficulty of interpretation, because of socioeconomic influences and other environmental factors....

  16. The Role of Carotenoids in Human Skin

    Directory of Open Access Journals (Sweden)

    Theognosia Vergou

    2011-12-01

    Full Text Available The human skin, as the boundary organ between the human body and the environment, is under the constant influence of free radicals (FR, both from the outside in and from the inside out. Carotenoids are known to be powerful antioxidant substances playing an essential role in the reactions of neutralization of FR (mainly reactive oxygen species ROS. Carotenoid molecules present in the tissue are capable of neutralizing several attacks of FR, especially ROS, and are then destroyed. Human skin contains carotenoids, such as α-, γ-, β-carotene, lutein, zeaxanthin, lycopene and their isomers, which serve the living cells as a protection against oxidation. Recent studies have reported the possibility to investigate carotenoids in human skin quickly and non-invasively by spectroscopic means. Results obtained from in-vivo studies on human skin have shown that carotenoids are vital components of the antioxidative protective system of the human skin and could serve as marker substances for the overall antioxidative status. Reflecting the nutritional and stress situation of volunteers, carotenoids must be administered by means of antioxidant-rich products, e.g., in the form of fruit and vegetables. Carotenoids are degraded by stress factors of any type, inter alia, sun radiation, contact with environmental hazards, illness, etc. The kinetics of the accumulation and degradation of carotenoids in the skin have been investigated.

  17. Non-lipophilic mycobiota of human skin

    Directory of Open Access Journals (Sweden)

    Katarzyna Talaga

    2016-01-01

    Full Text Available The human skin is inhabited by many species of bacteria and fungi, which are its natural microbiota. Fungi colonizing the skin, including those causing disease, characterized by great variety and variability, can be influenced by various factors. The purpose of this study was to investigate the composition of the non-lipid-dependent fungal microbiota of skin, including the presence of species potentially pathogenic for humans. Fifty-six volunteers of both sexes aged 22–78 were subjected to the study. Swabs were taken from the face, chest, back and interdigital spaces of hands. Mycobiota isolated proved to vary both in terms of the location of occurrence and gender of patients. Interdigital spaces of hands, dominated by yeasts, constitute a location on human skin most contaminated with fungi. Molds were more often isolated from the face and chest. The back was the least contaminated location. There was no difference in fungal incidence in relation to sex.

  18. Developing a predictive model of human skin coloring

    Science.gov (United States)

    Cotton, Symon; Claridge, Ela

    1996-04-01

    A model of color formation within human skin has been developed to aid the characterization of pigmented skin lesions from their digitized color images. The model is based on the Kublenka-Munk theory of scattering and absorption within inhomogeneous materials and the physics pertaining to their color properties. By considering the skin to be a layered construction of such materials, the stratum corneum, epidermis, papillary dermis and reticular dermis, and by exploiting the physics related to the optical interface between these layers, the model generates all possible colors occurring within normal human skin. In particular, the model predicts that all skin colors have to lie on a simple curved surface patch within a three- dimensional color space bounded by two physiologically meaningful axes, one corresponding to the amount of melanin within the epidermis and the other to the amount of blood within the dermis. These predictions were verified by comparing the CIE LMS coordinates of a representative, cross-racial sample of fifty skin images with the LMS coordinates predicted by the model. The results show that, within the predicted error bounds, the coordinates for normal skin colors do indeed lie on the curved surface generated by the model. Several possible applications of this representation are outlined, including images representing the melanin and blood components separately, as well as the possibility of measuring the Breslow thickness of melanocytic invasion within malignant melanoma.

  19. The x-ray crystal structure of the keratin 1?keratin 10 helix 2B heterodimer reveals molecular surface properties and biochemical insights into human skin disease

    OpenAIRE

    Bunick, Christopher G.; Milstone, Leonard M.

    2016-01-01

    Keratins 1 (K1) and 10 (K10) are the primary keratins expressed in differentiated epidermis. Mutations in K1/K10 are associated with human skin diseases. We determined the crystal structure of the complex between the distal (2B) helices of K1 and K10 to better understand how human keratin structure correlates with function. The 3.3? resolution structure confirms many features inferred by previous biochemical analyses but adds new, unexpected insights. It demonstrates a parallel, coiled-coil h...

  20. Elucidation of xenobiotic metabolism pathways in human skin and human skin models by proteomic profiling.

    Directory of Open Access Journals (Sweden)

    Sven van Eijl

    Full Text Available BACKGROUND: Human skin has the capacity to metabolise foreign chemicals (xenobiotics, but knowledge of the various enzymes involved is incomplete. A broad-based unbiased proteomics approach was used to describe the profile of xenobiotic metabolising enzymes present in human skin and hence indicate principal routes of metabolism of xenobiotic compounds. Several in vitro models of human skin have been developed for the purpose of safety assessment of chemicals. The suitability of these epidermal models for studies involving biotransformation was assessed by comparing their profiles of xenobiotic metabolising enzymes with those of human skin. METHODOLOGY/PRINCIPAL FINDINGS: Label-free proteomic analysis of whole human skin (10 donors was applied and analysed using custom-built PROTSIFT software. The results showed the presence of enzymes with a capacity for the metabolism of alcohols through dehydrogenation, aldehydes through dehydrogenation and oxidation, amines through oxidation, carbonyls through reduction, epoxides and carboxylesters through hydrolysis and, of many compounds, by conjugation to glutathione. Whereas protein levels of these enzymes in skin were mostly just 4-10 fold lower than those in liver and sufficient to support metabolism, the levels of cytochrome P450 enzymes were at least 300-fold lower indicating they play no significant role. Four epidermal models of human skin had profiles very similar to one another and these overlapped substantially with that of whole skin. CONCLUSIONS/SIGNIFICANCE: The proteomics profiling approach was successful in producing a comprehensive analysis of the biotransformation characteristics of whole human skin and various in vitro skin models. The results show that skin contains a range of defined enzymes capable of metabolising different classes of chemicals. The degree of similarity of the profiles of the in vitro models indicates their suitability for epidermal toxicity testing. Overall, these

  1. Cortisol extraction through human skin by reverse iontophoresis.

    Science.gov (United States)

    Ventura, Stephanie A; Heikenfeld, Jason; Brooks, Tiffany; Esfandiari, Leyla; Boyce, Steven; Park, Yoonjee; Kasting, Gerald B

    2017-04-01

    Continuous monitoring of cortisol at the surface of the skin would advance the diagnosis and treatment of cortisol-related diseases, or of elevated cortisol levels related to stress in otherwise healthy populations. Reliable and accurate detection of cortisol at the skin surface remains a limiting factor in real-time monitoring of cortisol. To address this limitation, cortisol extraction through excised human skin by reverse iontophoresis was studied in vitro in side-by-side diffusion cells using a radiolabeled probe. The skin was subjected to four direct current regimens (0, 28, 56, 113μAcm -2 ) with the anode in the donor chamber and the cumulative cortisol concentrations recorded in the receiver chamber. The 56 and 113μAcm -2 regimens significantly increased transport of 3 H-cortisol through the skin, and current density correlated directly with transcutaneous transport of 3 H-cortisol. The threshold of detection of electroosmotic versus passive diffusion of cortisol through the skin was between 28 and 56μAcm -2 . The results of this study are significant in examining how lipophilic analytes found in the bloodstream respond to reverse iontophoresis across the skin. In addition, a device integration technique is presented which illustrates how continuous cortisol extraction and sensing could potentially be achieved in a conventional wearable format. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Forensic human identification using skin microbiomes.

    Science.gov (United States)

    Schmedes, Sarah E; Woerner, August E; Budowle, Bruce

    2017-09-08

    The human microbiome contributes significantly to the genetic content of the human body. Genetic and environmental factors help shape the microbiome, and as such, the microbiome can be unique to an individual. Previous studies have demonstrated the potential to use microbiome profiling for forensic applications, however a method has yet to identify stable features of skin microbiomes that produce high classification accuracies for samples collected over reasonably long time intervals. A novel approach is described to classify skin microbiomes to their donors by comparing two features types, Propionibacterium acnes pangenome presence/absence features and nucleotide diversities of stable clade-specific markers. Supervised learning was used to attribute skin microbiomes from 14 skin body sites from 12 healthy individuals sampled at three time points over a >2.5 year period with accuracies up to 100% for three body sites. Feature selection identified a reduced subset of markers from each body site that are highly individualizing, identifying 187 markers from 12 clades. Classification accuracies were compared in a formal model testing framework, and the results of this indicate that learners trained on nucleotide diversity perform significantly better than those trained on presence/absence encodings. This study used supervised learning to identify individuals with high accuracy and associated stable features from skin microbiomes over a period of up to almost 3 years. These selected features provide a preliminary marker panel for future development of a robust and reproducible method for skin microbiome profiling for forensic human identification.Importance A novel approach is described to attribute skin microbiomes, collected over a period of >2.5 years, to their individual hosts with a high degree of accuracy. Nucleotide diversities of stable clade-specific markers with supervised learning was used to classify skin microbiomes from a particular individual with up to

  3. [Study of skin retraction applied to the treatment of skin tumors. Mapping of the human body].

    Science.gov (United States)

    Dumas, P; Benatar, M; Cardot-Leccia, N; Lebreton, E; Chignon-Sicard, B

    2012-04-01

    Skin, the main organ of the human body, is equipped with own biomechanical characteristics, highly variable depending on intra-individual factors (location, weight status, dermatological diseases…) and interindividual (age, sex…). Despite some recent cutometric studies, our review of the literature shows that there is no currently reliable analytical model representing the biomechanical behavior of the skin. Yet, this is a central issue in dermatology surgery, especially in the treatment of skin tumors, for the proper observance of surgical margins. We studied prospectively on 75 resection specimens (about 71 patient(s)), for the treatment of skin lesions tumor suspicious or known malignant or benign. Room dimensions were measured before and 5 minutes after excision, leading us to calculate a ratio of retraction of the skin surface. This retraction was correlated with age, gender, tumor type, and anatomic location of the site of excision. The power of retraction of the skin varies significantly by region of the body. It is maximum in the upper limb (hand excluded) and in the cervical region. At the cephalic region, skin of the ear and periorbital skin have capacities of important early retraction. Unlike the lower limb (foot excluded), the back skin of the nose and face appear to be a minimum of shrinkage. Age also seems to change on that capacity shrinkage, sex would have no influence. Our study confirms the variations in the ability of skin retraction based on a number of factors. In dermato-oncology, that power retraction could cause significant differences between clinical surgical margins and final pathologist margins. We believe it must be taken into account by the couple surgeon-pathologist, especially in the context of invasive and/or recurrent tumors. Copyright © 2012. Published by Elsevier SAS.

  4. Effects of skin surface temperature on photoplethysmograph.

    Science.gov (United States)

    Jeong, In Cheol; Yoon, Hyungro; Kang, Hyunjeong; Yeom, Hojun

    2014-01-01

    Photoplethysmograph (PPG) has been widely used to investigate various cardiovascular conditions. Previous studies demonstrated effects of temperature of the measurement environment; however, an integrated evaluation has not been established in environments with gradual air temperature variation. The purpose of this study is to investigate variations and relationships of blood pressure (BP), PPG and cardiovascular parameters such as heart rate (HR), stroke volume (SV), cardiac output (CO) and total peripheral resistance (TPR), by changing skin surface temperature (SST). Local mild cooling and heating was conducted on 16 healthy subjects. The results showed that local SST changes affected Finometer blood pressures (Finger BP), PPG components and TPR, but not the oscillometric blood pressure (Central BP), HR, SV and CO, and indicated that temperature must be maintained and monitored to reliably evaluate cardiovascular conditions in temperature-varying environments.

  5. Effects of Skin Surface Temperature on Photoplethysmograph

    Directory of Open Access Journals (Sweden)

    In Choel Jeong

    2014-01-01

    Full Text Available Photoplethysmograph (PPG has been widely used to investigate various cardiovascular conditions. Previous studies demonstrated effects of temperature of the measurement environment; however, an integrated evaluation has not been established in environments with gradual air temperature variation. The purpose of this study is to investigate variations and relationships of blood pressure (BP, PPG and cardiovascular parameters such as heart rate (HR, stroke volume (SV, cardiac output (CO and total peripheral resistance (TPR, by changing skin surface temperature (SST. Local mild cooling and heating was conducted on 16 healthy subjects. The results showed that local SST changes affected Finometer blood pressures (Finger BP, PPG components and TPR, but not the oscillometric blood pressure (Central BP, HR, SV and CO, and indicated that temperature must be maintained and monitored to reliably evaluate cardiovascular conditions in temperature-varying environments.

  6. Enhancement of human skin facial revitalization by moringa leaf extract cream.

    Science.gov (United States)

    Ali, Atif; Akhtar, Naveed; Chowdhary, Farzana

    2014-05-01

    Solar ultraviolet exposure is the main cause of skin damage by initiation of reactive oxygen species (ROS) leading to skin collagen imperfection and eventually skin roughness. This can be reduced by proper revitalization of skin enhancing younger and healthier appearance. To evaluate the skin facial revitalization effect of a cream formulation containing the Moringa oleifera leaf extract on humans. Active cream containing 3% of the concentrated extract of moringa leaves was developed by entrapping in the inner aqueous phase of cream. Base contained no extract. Skin revitalizing parameters, i.e. surface, volume, texture parameters and surface evaluation of the living skin (SELS) were assessed comparatively after application of the base and active cream on human face using Visioscan(®) VC 98 for a period of 3 months. Surface values were increased by the base and decreased by the active cream. Effects produced for the base and active cream were significant and insignificant, respectively, as observed in the case of surface. Unlike the base, the active cream showed significant effects on skin volume, texture parameters (energy, variance and contrast) and SELS, SEr (skin roughness), SEsc (skin scaliness), SEsm (skin smoothness), and SEw (skin wrinkles) parameters. The results suggested that moringa cream enhances skin revitalization effect and supports anti-aging skin effects.

  7. Contact modelling of human skin: what value to use for the modulus of elasticity?

    NARCIS (Netherlands)

    van Kuilenburg, Julien; Masen, Marc Arthur; van der Heide, Emile

    2012-01-01

    In modelling and understanding the contact and friction behaviour of human skin, the elastic modulus of the skin is an important input parameter. For the development of design rules for the engineering of surfaces in contact with the skin an expression that describes the relation between the elastic

  8. RNA Aptamer Delivery through Intact Human Skin.

    Science.gov (United States)

    Lenn, Jon D; Neil, Jessica; Donahue, Christine; Demock, Kellie; Tibbetts, Caitlin Vestal; Cote-Sierra, Javier; Smith, Susan H; Rubenstein, David; Therrien, Jean-Philippe; Pendergrast, P Shannon; Killough, Jason; Brown, Marc B; Williams, Adrian C

    2018-02-01

    It is generally recognized that only relatively small molecular weight (typically aptamer, highly specific to the human IL-23 cytokine, with picomolar activity. Results demonstrate penetration of the aptamer into freshly excised human skin using two different fluorescent labels. A dual hybridization assay quantified aptamer from the epidermis and dermis, giving levels far exceeding the cellular half maximal inhibitory concentration values (>100,000-fold), and aptamer integrity was confirmed using an oligonucleotide precipitation assay. A T helper 17 response was stimulated in freshly excised human skin resulting in significantly upregulated IL-17f, and IL-22; topical application of the IL-23 aptamer decreased both IL-17f and IL-22 by approximately 45% but did not result in significant changes to IL-23 mRNA levels, confirming that the aptamer did not globally suppress mRNA levels. This study demonstrates that very-large-molecular-weight RNA aptamers can permeate across the intact human skin barrier to therapeutically relevant levels into both the epidermis and dermis and that the skin-penetrating aptamer retains its biologically active conformational structure capable of binding to endogenous IL-23. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  9. Human age and skin physiology shape diversity and abundance of Archaea on skin

    OpenAIRE

    Moissl-Eichinger, C; Probst, AJ; Birarda, G; Auerbach, A; Koskinen, K; Wolf, P; Holman, HYN

    2017-01-01

    © The Author(s) 2017. The human skin microbiome acts as an important barrier protecting our body from pathogens and other environmental influences. Recent investigations have provided evidence that Archaea are a constant but highly variable component of the human skin microbiome, yet factors that determine their abundance changes are unknown. Here, we tested the hypothesis that the abundance of archaea on human skin is influenced by human age and skin physiology by quantitative PCR of 51 diff...

  10. Comparative histology and immunohistochemistry of porcine versus human skin.

    Science.gov (United States)

    Debeer, Sabine; Le Luduec, Jean-Benoît; Kaiserlian, Dominique; Laurent, Philippe; Nicolas, Jean-François; Dubois, Bertrand; Kanitakis, Jean

    2013-01-01

    Porcine skin is increasingly being employed as a model of human skin in various research fields, including pharmacology, toxicology and immunology, with particular interest in percutaneous permeation and organ transplantation. Porcine skin shows several anatomical and physiological similarities, but also some differences, with human skin, but few in depth comparative studies are so far available. To study the immunohistochemical properties of normal porcine skin in comparison with human skin. We performed a histological and immunohistochemical study on frozen and formalin-fixed, paraffin-embedded skin biopsies from domestic swine and normal human skin, using a panel of 93 monoclonal or polyclonal antibodies recognizing various human and porcine skin cell types or structures. We found that several antibodies used to detect normal human skin cells showed equivalent immunoreactivity on normal porcine skin. However, some antibodies commonly used to detect human skin antigens remained unreactive on porcine skin. Our findings highlight the main immunohistochemical properties of porcine skin in comparison with those of human skin and provide a morphological and immunohistochemical basis useful to researchers using porcine skin.

  11. Satellite Sensed Skin Sea Surface Temperature

    Science.gov (United States)

    Donlon, Craig

    1997-01-01

    Quantitative predictions of spatial and temporal changes the global climate rely heavily on the use of computer models. Unfortunately, such models cannot provide the basis for climate prediction because key physical processes are inadequately treated. Consequently, fine tuning procedures are often used to optimize the fit between model output and observational data and the validation of climate models using observations is essential if model based predictions of climate change are to be treated with any degree of confidence. Satellite Sea Surface Temperature (SST) observations provide high spatial and temporal resolution data which is extremely well suited to the initialization, definition of boundary conditions and, validation of climate models. In the case of coupled ocean-atmosphere models, the SST (or more correctly the 'Skin' SST (SSST)) is a fundamental diagnostic variable to consider in the validation process. Daily global SST maps derived from satellite sensors also provide adequate data for the detection of global patterns of change which, unlike any other SST data set, repeatedly extend into the southern hemisphere extra-tropical regions. Such data are essential to the success of the spatial 'fingerprint' technique, which seeks to establish a north-south asymmetry where warming is suppressed in the high latitude Southern Ocean. Some estimates suggest that there is a greater than 80% chance of directly detecting significant change (97.5 % confidence level) after 10-12 years of consistent global observations of mean sea surface temperature. However, these latter statements should be qualified with the assumption that a negligible drift in the observing system exists and that biases between individual instruments required to derive a long term data set are small. Given that current estimates for the magnitude of global warming of 0.015 K yr(sup -1) - 0.025 K yr(sup -1), satellite SST data sets need to be both accurate and stable if such a warming trend is to

  12. In vivo optical elastography: stress and strain imaging of human skin lesions

    Science.gov (United States)

    Es'haghian, Shaghayegh; Gong, Peijun; Kennedy, Kelsey M.; Wijesinghe, Philip; Sampson, David D.; McLaughlin, Robert A.; Kennedy, Brendan F.

    2015-03-01

    Probing the mechanical properties of skin at high resolution could aid in the assessment of skin pathologies by, for example, detecting the extent of cancerous skin lesions and assessing pathology in burn scars. Here, we present two elastography techniques based on optical coherence tomography (OCT) to probe the local mechanical properties of skin. The first technique, optical palpation, is a high-resolution tactile imaging technique, which uses a complaint silicone layer positioned on the tissue surface to measure spatially-resolved stress imparted by compressive loading. We assess the performance of optical palpation, using a handheld imaging probe on a skin-mimicking phantom, and demonstrate its use on human skin. The second technique is a strain imaging technique, phase-sensitive compression OCE that maps depth-resolved mechanical variations within skin. We show preliminary results of in vivo phase-sensitive compression OCE on a human skin lesion.

  13. The X-Ray Crystal Structure of the Keratin 1-Keratin 10 Helix 2B Heterodimer Reveals Molecular Surface Properties and Biochemical Insights into Human Skin Disease

    Energy Technology Data Exchange (ETDEWEB)

    Bunick, Christopher G.; Milstone, Leonard M.

    2017-01-01

    Keratins 1 (K1) and 10 (K10) are the primary keratins expressed in differentiated epidermis. Mutations in K1/K10 are associated with human skin diseases. We determined the crystal structure of the complex between the distal (2B) helices of K1 and K10 to better understand how human keratin structure correlates with function. The 3.3 Å resolution structure confirms many features inferred by previous biochemical analyses, but adds unexpected insights. It demonstrates a parallel, coiled-coil heterodimer with a predominantly hydrophobic intermolecular interface; this heterodimer formed a higher order complex with a second K1-K10-2B heterodimer via a Cys401K10 disulfide link, although the bond angle is unanticipated. The molecular surface analysis of K1-K10-2B identified several pockets, one adjacent to the disulfide linkage and conserved in K5-K14. The solvent accessible surface area of the K1-K10 structure is 20–25% hydrophobic. The 2B region contains mixed acidic and basic patches proximally (N-terminal), whereas it is largely acidic distally (C-terminal). Mapping of conserved and nonconserved residues between K1-K10 and K5-K14 onto the structure demonstrated the majority of unique residues align along the outer helical ridge. Finally, the structure permitted a fresh analysis of the deleterious effects caused by K1/K10 missense mutations found in patients with phenotypic skin disease.

  14. The isolated perfused human skin flap model: A missing link in skin penetration studies?

    Science.gov (United States)

    Ternullo, Selenia; de Weerd, Louis; Flaten, Gøril Eide; Holsæter, Ann Mari; Škalko-Basnet, Nataša

    2017-01-01

    Development of effective (trans)dermal drug delivery systems requires reliable skin models to evaluate skin drug penetration. The isolated perfused human skin flap remains metabolically active tissue for up to 6h during in vitro perfusion. We introduce the isolated perfused human skin flap as a close-to-in vivo skin penetration model. To validate the model's ability to evaluate skin drug penetration the solutions of a hydrophilic (calcein) and a lipophilic (rhodamine) fluorescence marker were applied. The skin flaps were perfused with modified Krebs-Henseleit buffer (pH7.4). Infrared technology was used to monitor perfusion and to select a well-perfused skin area for administration of the markers. Flap perfusion and physiological parameters were maintained constant during the 6h experiments and the amount of markers in the perfusate was determined. Calcein was detected in the perfusate, whereas rhodamine was not detectable. Confocal images of skin cross-sections shoved that calcein was uniformly distributed through the skin, whereas rhodamine accumulated in the stratum corneum. For comparison, the penetration of both markers was evaluated on ex vivo human skin, pig skin and cellophane membrane. The proposed perfused flap model enabled us to distinguish between the penetrations of the two markers and could be a promising close-to-in vivo tool in skin penetration studies and optimization of formulations destined for skin administration. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Predicting Biological Age from a Skin Surface Capacitive Analysis

    Science.gov (United States)

    Bevilacqua, Alessandro; Gherardi, Alessandro; Ferri, Massimo

    The skin is the largest (and the most exposed) organ of the body both in terms of surface area and weight. Its care is of great importance for both aesthetics and health issues. Often, the skin appearance gives us information about the skin health status as well as hints at the biological age. Therefore, the skin surface characterization is of great significance for dermatologists as well as for cosmetic scientists in order to evaluate the effectiveness of medical or cosmetic treatments. So far, no in vivo measurements regarding skin topography characterization could be achieved routinely to evaluate skin aging. This work describes how a portable capacitive device, normally used for fingerprint acquisition, can be utilized to achieve measures of skin aging routinely. The capacitive images give a high resolution (50 μm) representation of skin topography, in terms of wrinkles and cells. In this work, we have addressed the latter: through image segmentation techniques, cells have been localized and identified and a feature related to their area distribution has been generated. Accurate experiments accomplished in vivo show how the feature we conceived is linearly related to skin aging. Besides, since this finding has been achieved using a low cost portable device, this could boost research in this field as well as open doors to an application based on an embedded system.

  16. Surface electrical capacitance as an index of epidermal barrier properties of composite skin substitutes and skin autografts.

    Science.gov (United States)

    Goretsky, M J; Supp, A P; Greenhalgh, D G; Warden, G D; Boyce, S T

    1995-01-01

    Restoration of the epidermal barrier is a requirement for burn wound closure. A rapid, reliable, and noninvasive measure of the rate of restoration of the epidermal barrier is not readily available. To monitor the reformation of the epidermal barrier, we measured surface electrical capacitance on cultured skin substitutes (human keratinocytes and fibroblasts attached to collagen-glycosaminoglycan substrates) and split-thickness skin autografts grafted to patients. Data were collected from four patients with burns and one pediatric patient with a congenital hairy nevus comprising > 60% total body surface area. Capacitance measurements were performed at days 7, 10, 12, 14, and 28 by direct contact of the capacitance probe for 10 seconds to the cultured skin substitutes or split-thickness autograft. On postoperative days 7, 10, 12, 14, 21, and 28, the surface electrical capacitance of cultured skin substitutes after 10 seconds of sampling was 2468 +/- 268, 1443 +/- 439, 129 +/- 43, 200 +/- 44, 88 +/- 20, and 74 +/- 19 picofarads (mean +/- standard error of the mean), respectively. Surface electrical capacitance for split-thickness autograft on the same days was 1699 +/- 371, 1914 +/- 433, 125 +/- 16, 175 +/- 63, 110 +/- 26, 271 +/- 77 picofarads, respectively. Surface electrical capacitance in all of the grafts decreased with time. Cultured skin substitutes had approximately the same 10-second capacitance values as split-thickness autograft during 3 weeks of healing and approached values for uninjured skin (32 +/- 5 picofarads) by 12 days. Measurement of surface electrical capacitance is a direct, inexpensive, and convenient index for noninvasive monitoring of epidermal barrier formation.

  17. Experimental Study of the Course of Threshold Current, Voltage and Electrode Impedance During Stepwise Stimulation From the Skin Surface to the Human Cortex

    NARCIS (Netherlands)

    Szelenyi, Andrea; Journee, Henricus Louis; Herrlich, Simon; Galistu, Gianni M.; van den Berg, Joris; van Dijk, J. Marc C.

    Background: Transcranial electric stimulation as used during intraoperative neurostimulation is dependent on electrode and skull impedances. Objective: Threshold currents, voltages and electrode impedances were evaluated with electrical stimulation at 8 successive layers between the skin and the

  18. The top skin-associated genes: a comparative analysis of human and mouse skin transcriptomes.

    Science.gov (United States)

    Gerber, Peter Arne; Buhren, Bettina Alexandra; Schrumpf, Holger; Homey, Bernhard; Zlotnik, Albert; Hevezi, Peter

    2014-06-01

    The mouse represents a key model system for the study of the physiology and biochemistry of skin. Comparison of skin between mouse and human is critical for interpretation and application of data from mouse experiments to human disease. Here, we review the current knowledge on structure and immunology of mouse and human skin. Moreover, we present a systematic comparison of human and mouse skin transcriptomes. To this end, we have recently used a genome-wide database of human gene expression to identify genes highly expressed in skin, with no, or limited expression elsewhere - human skin-associated genes (hSAGs). Analysis of our set of hSAGs allowed us to generate a comprehensive molecular characterization of healthy human skin. Here, we used a similar database to generate a list of mouse skin-associated genes (mSAGs). A comparative analysis between the top human (n=666) and mouse (n=873) skin-associated genes (SAGs) revealed a total of only 30.2% identity between the two lists. The majority of shared genes encode proteins that participate in structural and barrier functions. Analysis of the top functional annotation terms revealed an overlap for morphogenesis, cell adhesion, structure, and signal transduction. The results of this analysis, discussed in the context of published data, illustrate the diversity between the molecular make up of skin of both species and grants a probable explanation, why results generated in murine in vivo models often fail to translate into the human.

  19. Liposome surface charge influence on skin penetration behaviour.

    Science.gov (United States)

    Gillet, A; Compère, P; Lecomte, F; Hubert, P; Ducat, E; Evrard, B; Piel, G

    2011-06-15

    Vesicular systems have shown their ability to increase dermal and transdermal drug delivery. Their mechanism of drug transport into and through the skin has been investigated but remains a much debated question. Several researchers have outlined that drug penetration can be influenced by modifying the surface charge of liposomes. In the present work we study the influence of particle surface charge on skin penetration. The final purpose is the development of a carrier system which is able to enhance the skin delivery of two model drugs, betamethasone and betamethasone dipropionate. Liposomes were characterised by their size, morphology, zeta potential, encapsulation efficiency and stability. Ex vivo diffusion studies using Franz diffusion cells were performed. Confocal microscopy was performed to visualise the penetration of fluorescently labelled liposomes into the skin. This study showed the potential of negatively charged liposomes to enhance the skin penetration of betamethasone and betamethasone dipropionate. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Study on radiation transfer in human skin for cosmetics

    Science.gov (United States)

    Yamada, Jun; Kawamura, Ayumu; Miura, Yoshimasa; Takata, Sadaki; Ogawa, Katsuki

    2005-06-01

    In order to design cosmetics producing the optical properties that are required for a beautiful skin, the radiation transfer in the skin has been numerically investigated by the Monte Carlo method and the effects of skin texture and cosmetics on the radiation transfer have been empirically investigated using an artificial skin. The numerical analysis showed that the total internal reflection suppresses large portion of radiation going out through the skin surface Additionally, the experimental study revealed that skin texture and cosmetics not only diffusely reflect the incoming radiation, but also lead the internally reflected radiation to the outside of the skin.

  1. Characterization of porcine skin as a model for human skin studies using infrared spectroscopic imaging.

    Science.gov (United States)

    Kong, Rong; Bhargava, Rohit

    2011-06-07

    Porcine skin is often considered a substitute for human skin based on morphological and functional data, for example, for transdermal drug diffusion studies. A chemical, structural and temporal characterization of porcine skin in comparison to human skin is not available but will likely improve our understanding of this porcine skin model. Here, we employ Fourier transform infrared (FT-IR) spectroscopic imaging to holistically measure chemical species as well as spatial structure as a function of time to characterize porcine skin as a model for human skin. Porcine skin was found to resemble human skin spectroscopically and differences are elucidated. Cryo-prepared fresh porcine skin samples for spectroscopic imaging were found to be stable over time and small variations are observed. Hence, we extended characterization to the use of this model for dynamic processes. In particular, the capacity and stability of this model in transdermal diffusion is examined. The results indicate that porcine skin is likely to be an attractive tool for studying diffusion dynamics of materials in human skin.

  2. Visible skin condition and perception of human facial appearance.

    Science.gov (United States)

    Samson, N; Fink, B; Matts, P J

    2010-06-01

    Evolutionary psychology suggests that certain human beauty standards have evolved to provide reliable cues of fertility and health. Hence, preferences for some physical characteristics of the face and body are thought to reflect adaptations for the promotion of mate choice. Studies that have investigated facial attractiveness have concentrated mainly on features such as symmetry, averageness and sex-typical traits, which are developed under the influence of sex steroids. Few studies, however, have addressed the effect of human skin condition on perception of facial appearance in this context, and possible implications for sexual selection. There is now accumulating evidence that skin pigmentation and skin surface topography cues, particularly in women, have a significant influence on attractiveness judgements, as they seem primarily to signal aspects of age and health. This article (i) reviews briefly some of the main determinants of visible skin condition, (ii) presents recent evidence on its signalling value in face perception and (iii) suggests areas for future research with reference to an evolutionary psychology framework.

  3. Relating friction on the human skin to the hydration and temperature of the skin

    NARCIS (Netherlands)

    Veijgen, N.K.; Masen, M.A.; Heide, E. van der

    2013-01-01

    The human skin is constantly in interaction with materials and products. Therefore, skin friction is relevant to all people. In the literature, the frictional properties of the skin have been linked to a large variety of variables, like age, gender and hydration. The present study compares the data

  4. Fabrication and surface modification of macroporous poly(L-lactic acid) and poly(L-lactic-co-glycolic acid) (70/30) cell scaffolds for human skin fibroblast cell culture.

    Science.gov (United States)

    Yang, Jian; Shi, Guixin; Bei, Jianzhong; Wang, Shenguo; Cao, Yilin; Shang, Qingxin; Yang, Guanghui; Wang, Wenjing

    2002-12-05

    The fabrication and surface modification of a porous cell scaffold are very important in tissue engineering. Of most concern are high-density cell seeding, nutrient and oxygen supply, and cell affinity. In the present study, poly(L-lactic acid) and poly(L-lactic-co-glycolic acid) (70/30) cell scaffolds with different pore structures were fabricated. An improved method based on Archimedes' Principle for measuring the porosity of scaffolds, using a density bottle, was developed. Anhydrous ammonia plasma treatment was used to modify surface properties to improve the cell affinity of the scaffolds. The results show that hydrophilicity and surface energy were improved. The polar N-containing groups and positive charged groups also were incorporated into the sample surface. A low-temperature treatment was used to maintain the plasma-modified surface properties effectively. It would do help to the further application of plasma treatment technique. Cell culture results showed that pores smaller than 160 microm are suitable for human skin fibroblast cell growth. Cell seeding efficiency was maintained at above 99%, which is better than the efficiency achieved with the common method of prewetting by ethanol. The plasma-treatment method also helped to resolve the problem of cell loss during cell seeding, and the negative effects of the ethanol trace on cell culture were avoided. The results suggest that anhydrous ammonia plasma treatment enhances the cell affinity of porous scaffolds. Mass transport issues also have been considered. Copyright 2002 Wiley Periodicals, Inc.

  5. Total skin electron irradiation: evaluation of dose uniformity throughout the skin surface.

    Science.gov (United States)

    Anacak, Yavuz; Arican, Zumre; Bar-Deroma, Raquel; Tamir, Ada; Kuten, Abraham

    2003-01-01

    In this study, in vivo dosimetic data of 67 total skin electron irradiation (TSEI) treatments were analyzed. Thermoluminescent dosimetry (TLD) measurements were made at 10 different body points for every patient. The results demonstrated that the dose inhomogeneity throughout the skin surface is around 15%. The homogeneity was better at the trunk than at the extratrunk points, and was worse when a degrader was used. There was minimal improvement of homogeneity in subsequent days of treatment.

  6. Comparison of human and porcine skin for characterization of sunscreens

    Science.gov (United States)

    Weigmann, Hans-Jürgen; Schanzer, Sabine; Patzelt, Alexa; Bahaban, Virginie; Durat, Fabienne; Sterry, Wolfram; Lademann, Jürgen

    2009-03-01

    The universal sun protection factor (USPF) characterizing sunscreen efficacy based on spectroscopically determined data, which were obtained using the tape stripping procedure. The USPF takes into account the complete ultraviolet (UV) spectral range in contrast to the classical sun protection factor (SPF). Until now, the USPF determination has been evaluated only in human skin. However, investigating new filters not yet licensed excludes in vivo investigation on human skin but requires the utilization of a suitable skin model. The penetration behavior and the protection efficacy of 10 commercial sunscreens characterized by USPF were investigated, comparing human and porcine skin. The penetration behavior found for typical UV filter substances is nearly identical for both skin types. The comparison of the USPF obtained for human and porcine skin results in a linear relation between both USPF values with a correlation factor R2=0.98. The results demonstrate the possibility for the use of porcine skin to determine the protection efficacy of sunscreens.

  7. Human skin equivalent as an alternative to animal testing

    OpenAIRE

    Mertsching, Heike; Weimer, Michaela; Kersen, Silke; Brunner, Herwig

    2008-01-01

    The 3-D skin equivalent can be viewed as physiologically comparable to the natural skin and therefore is a suitable alternative for animal testing. This highly differentiated in vitro human skin equivalent is used to assess the efficacy and mode of action of novel agents. This model is generated from primary human keratinocytes on a collagen substrate containing human dermal fibroblasts. It is grown at the air-liquid interface which allows full epidermal stratification and epidermal-dermal in...

  8. Chromium content in human skin after in vitro application of ordinary cement and ferrous-sulphate-reduced cement

    DEFF Research Database (Denmark)

    Fullerton, A; Gammelgaard, Bente; Avnstorp, C

    1993-01-01

    The amount of chromium found in human skin after in vitro application of cement suspensions on full-thickness human skin in diffusion cells was investigated. Cement suspensions made from ordinary Portland cement or Portland cement with the chromate reduced with added ferrous sulphate were used....... The cement suspensions were either applied on the skin surface under occlusion for 48 h or applied repeatedly every 24 h for 96 h. No statistically significant difference in chromium content of skin layers between skin exposed to ordinary Portland cement, skin exposed to cement with added ferrous sulphate...... and unexposed skin was observed, despite a more permeable skin barrier at the alkaline pH of the cement suspensions, i.e., pH 12.5. Increased chromium levels in epidermis and dermis were seen when ordinary Portland cement was applied as a suspension with added sodium sulphate (20%) on the skin surface for 96 h...

  9. Chemical ecology of interactions between human skin microbiota and mosquitoes

    NARCIS (Netherlands)

    Verhulst, N.O.; Takken, W.; Dicke, M.; Schraa, G.; Smallegange, R.C.

    2010-01-01

    Microbiota on the human skin plays a major role in body odour production. The human microbial and chemical signature displays a qualitative and quantitative correlation. Genes may influence the chemical signature by shaping the composition of the microbiota. Recent studies on human skin microbiota,

  10. Structure, biomimetics, and fluid dynamics of fish skin surfaces*

    Science.gov (United States)

    Lauder, George V.; Wainwright, Dylan K.; Domel, August G.; Weaver, James C.; Wen, Li; Bertoldi, Katia

    2016-10-01

    The interface between the fluid environment and the surface of the body in swimming fishes is critical for both physiological and hydrodynamic functions. The skin surface in most species of fishes is covered with bony scales or toothlike denticles (in sharks). Despite the apparent importance of fish surfaces for understanding aquatic locomotion and near-surface boundary layer flows, relatively little attention has been paid to either the nature of surface textures in fishes or possible hydrodynamic effects of variation in roughness around the body surface within an individual and among species. Fish surfaces are remarkably diverse and in many bony fishes scales can have an intricate surface texture with projections, ridges, and comblike extensions. Shark denticles (or scales) are toothlike and project out of the skin to form a complexly textured surface that interacts with free-stream flow. Manufacturing biomimetic foils with fishlike surfaces allows hydrodynamic testing and we emphasize here the importance of dynamic test conditions where the effect of surface textures is assessed under conditions of self-propulsion. We show that simple two-dimensional foils with patterned cuts do not perform as well as a smooth control surface, but that biomimetic shark skin foils can swim at higher self-propelled speeds than smooth controls. When the arrangement of denticles on the foil surface is altered, we find that a staggered-overlapped pattern outperforms other arrangements. Flexible foils made of real shark skin outperform sanded controls when foils are moved with a biologically realistic motion program. We suggest that focus on the mechanisms of drag reduction by fish surfaces has been too limiting and an additional role of fish surface textures may be to alter leading edge vortices and flow patterns on moving surfaces in a way that enhances thrust. Analysis of water flow over an artificial shark skin foil under both static and dynamic conditions shows that a shear layer

  11. A custom tailored model to investigate skin penetration in porcine skin and its comparison with human skin.

    Science.gov (United States)

    Herbig, Michael E; Houdek, Pia; Gorissen, Sascha; Zorn-Kruppa, Michaela; Wladykowski, Ewa; Volksdorf, Thomas; Grzybowski, Stephan; Kolios, Georgios; Willers, Christoph; Mallwitz, Henning; Moll, Ingrid; Brandner, Johanna M

    2015-09-01

    Reliable models for the determination of skin penetration and permeation are important for the development of new drugs and formulations. The intention of our study was to develop a skin penetration model which (1) is viable and well supplied with nutrients during the period of the experiment (2) is mimicking human skin as far as possible, but still is independent from the problems of supply and heterogeneity, (3) can give information about the penetration into different compartments of the skin and (4) considers specific inter-individual differences in skin thickness. In addition, it should be quick and inexpensive (5) and without ethical implications (6). Using a chemically divers set of four topically approved active pharmaceutical ingredients (APIs), namely diclofenac, metronidazole, tazarotene, and terbinafine, we demonstrated that the model allows reliable determination of drug concentrations in different layers of the viable epidermis and dermis. For APIs susceptible for skin metabolism, the extent of metabolic transformation in epidermis and dermis can be monitored. Furthermore, a high degree of accordance in the ability for discrimination of skin concentrations of the substances in different layers was found in models derived from porcine and human skin. Viability, proliferation, differentiation and markers for skin barrier function were surveyed in the model. This model, which we call 'Hamburg model of skin penetration' is particularly suited to support a rational ranking and selection of dermatological formulations within drug development projects. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Porphyrin Metabolisms in Human Skin Commensal Propionibacterium acnes Bacteria: Potential Application to Monitor Human Radiation Risk

    Science.gov (United States)

    Shu, M.; Kuo, S.; Wang, Y.; Jiang, Y.; Liu, Y.-T.; Gallo, R.L.; Huang, C.-M.

    2013-01-01

    Propionibacterium acnes (P. acnes), a Gram-positive anaerobic bacterium, is a commensal organism in human skin. Like human cells, the bacteria produce porphyrins, which exhibit fluorescence properties and make bacteria visible with a Wood’s lamp. In this review, we compare the porphyrin biosynthesis in humans and P. acnes. Also, since P. acnes living on the surface of skin receive the same radiation exposure as humans, we envision that the changes in porphyrin profiles (the absorption spectra and/or metabolism) of P. acnes by radiation may mirror the response of human cells to radiation. The porphyrin profiles of P. acnes may be a more accurate reflection of radiation risk to the patient than other biodosimeters/biomarkers such as gene up-/down-regulation, which may be non-specific due to patient related factors such as autoimmune diseases. Lastly, we discuss the challenges and possible solutions for using the P. acnes response to predict the radiation risk. PMID:23231351

  13. Acute effects of cold therapy on knee skin surface temperature: gel pack versus ice bag.

    Science.gov (United States)

    Breslin, Matthew; Lam, Patrick; Murrell, George A C

    2015-01-01

    To our knowledge there has been no research that has compared the effectiveness of two popular cold therapy modalities applied to healthy human knees, with a surgical dressing, over a 4 h period. To determine whether gel packs are more effective than ice bags at reducing skin surface temperature in humans. This was a randomised, repeated measures crossover study, which included nine healthy participants. Level 2. Two cold therapy modalities-a gel pack (DonJoy-Orthopaedic Pty Ltd, Normanhurst, New South Wales, Australia) and an ice bag (ICE'N'EASY, Bokarina, Queensland, Australia)-were applied on top of a surgical dressing, covering the knee. Each participant randomly received two cold therapy treatments, in separate sessions, at least 4 days apart. Each session utilised the time protocol of 20 min application on the hour, for 4 h. Skin surface temperature was recorded throughout the session at 1 min intervals. In the first application, the ice bag (5°C±1.7°C) was more effective at reducing skin surface temperature (pice bag initially was more effective than the gel pack at reducing skin surface temperature of healthy knees, with a surgical dressing. Over a 4 h period both gel packs and ice bags were just as effective at reducing skin surface temperature and at maintaining these lower temperatures.

  14. Setup for investigating gold nanoparticle penetration through reconstructed skin and comparison to published human skin data

    Science.gov (United States)

    Labouta, Hagar I.; Thude, Sibylle; Schneider, Marc

    2013-06-01

    Owing to the limited source of human skin (HS) and the ethical restrictions of using animals in experiments, in vitro skin equivalents are a possible alternative for conducting particle penetration experiments. The conditions for conducting penetration experiments with model particles, 15-nm gold nanoparticles (AuNP), through nonsealed skin equivalents are described for the first time. These conditions include experimental setup, sterility conditions, effective applied dose determination, skin sectioning, and skin integrity check. Penetration at different exposure times (two and 24 h) and after tissue fixation (fixed versus unfixed skin) are examined to establish a benchmark in comparison to HS in an attempt to get similar results to HS experiments presented earlier. Multiphoton microscopy is used to detect gold luminescence in skin sections. λex=800 nm is used for excitation of AuNP and skin samples, allowing us to determine a relative index for particle penetration. Despite the observed overpredictability of penetration into skin equivalents, they could serve as a first fast screen for testing the behavior of nanoparticles and extrapolate their penetration behavior into HS. Further investigations are required to test a wide range of particles of different physicochemical properties to validate the skin equivalent-human skin particle penetration relationship.

  15. Human age and skin physiology shape diversity and abundance of Archaea on skin.

    Science.gov (United States)

    Moissl-Eichinger, Christine; Probst, Alexander J; Birarda, Giovanni; Auerbach, Anna; Koskinen, Kaisa; Wolf, Peter; Holman, Hoi-Ying N

    2017-06-22

    The human skin microbiome acts as an important barrier protecting our body from pathogens and other environmental influences. Recent investigations have provided evidence that Archaea are a constant but highly variable component of the human skin microbiome, yet factors that determine their abundance changes are unknown. Here, we tested the hypothesis that the abundance of archaea on human skin is influenced by human age and skin physiology by quantitative PCR of 51 different skin samples taken from human subjects of various age. Our results reveal that archaea are more abundant in human subjects either older than 60 years or younger than 12 years as compared to middle-aged human subjects. These results, together with results obtained from spectroscopy analysis, allowed us gain first insights into a potential link of lower sebum levels and lipid content and thus reduced skin moisture with an increase in archaeal signatures. Amplicon sequencing of selected samples revealed the prevalence of specific eury- and mainly thaumarchaeal taxa, represented by a core archaeome of the human skin.

  16. Biogeography and individuality shape function in the human skin metagenome

    OpenAIRE

    Oh, Julia; Byrd, Allyson L.; Deming, Clay; Conlan, Sean; Kong, Heidi H.; Segre, Julia A.

    2014-01-01

    Summary The varied topography of human skin offers a unique opportunity to study how the body?s microenvironments influence the functional and taxonomic composition of microbial communities. Phylogenetic marker gene-based studies have identified many bacteria and fungi that colonize distinct skin niches. Here, metagenomic analyses of diverse body sites in healthy humans demonstrate that local biogeography and strong individuality define the skin microbiome. We developed a relational analysis ...

  17. Using human epithelial amnion cells in human de-epidermized dermis for skin regeneration.

    Science.gov (United States)

    Jiang, Lei-Wei; Chen, Hongduo; Lu, Hongguang

    2016-01-01

    Human amniotic epithelial cells (hAECs) is a desirable reserve of stem cells. Human de-epidermized dermis (DED) retains basic tissue structure and parts of the basement membrane (BM) components at the acelluIar dermal surface, and provides a potential tool for skin regeneration. To evaluate the potential role of hAECs in skin regeneration, we used DED to perform organotypic culture of hAECs to develop organotypic skin. HAECs were isolated and cultured. Biological characteristics of hAECs were determined by immunocytochemistry and flow cytometry. To prepare DED, the epidermis was removed and then repeated freeze-thaw cycles. HAECs and fibroblast were seeded onto DED to perform the submerged culture for 3 days and then to be maintained at the air-liquid interface for 14 days to form organotypic culture. To identify whether the obtained DED retain the BM structure and components, the histological characteristics of DED and the BM were detected by immunohistochemistry. To evaluate whether the organotypic skin has similar histological characteristics with normal human skin, the marks of epidermal proliferation and differentiation and basement membrane component were detected by immunohistochemistry. Moreover, cell ultrastructure, cell-cell contact and ultrastructure of BM were examined under the transmission electron microscopy. HAECs has stem-cell characteristics with strong pluripotent Oct-4 and embryonic marker SSEA-4 expression. DED has effectively cleansed the cell components and continuous distributions of laminin and collagen IV. The histological appearance of tissue-engineered skin in vitro has 4 to 9 continuous layers of stratified epithelium and is similar to normal human skin in morphology. Immunohistochemical studies revealed that proliferation and differentiation markers such as Ki67, CK19, CK14, CK10, filaggrin but not CK18 expressed similar pattern characteristics to normal human epidermis. In addition, Periodic acid-Schiff stain showed that a uniform red

  18. In vitro and human testing strategies for skin irritation.

    Science.gov (United States)

    Robinson, M K; Osborne, R; Perkins, M A

    2000-01-01

    Prior to the manufacture, transport, and marketing of chemicals or products, it is critical to assess their potential for skin toxicity (corrosion or irritation), thereby protecting the worker and consumer from adverse skin effects due to intended or accidental skin exposure. Traditionally, animal testing procedures have provided the data needed to assess the more severe forms of skin toxicity, and current regulations may require animal test data before permission can be obtained to manufacture, transport, or market chemicals or the products that contain them. In recent years, the use of animals to assess skin safety has been opposed by some as inhumane and unnecessary. The conflicting needs of the industrial toxicologist to (1) protect human safety, (2) comply with regulations, and (3) reduce animal testing have led to major efforts to develop alternative, yet predictive, test methods. A variety of in vitro skin corrosion test methods have been developed and several have successfully passed initial international validation. These have included skin or epidermal equivalent assays that have been shown to distinguish corrosive from noncorrosive chemicals. These skin/epidermal equivalent assays have also been modified and used to assess skin irritation potential relative to existing human exposure test data. The data show a good correlation between in vitro assay data and different types of human skin irritation data for both chemicals and consumer products. The effort to eliminate animal tests has also led to the development of a novel human patch test for assessment of acute skin irritation potential. A case study shows the benefits of in vitro and human skin irritation tests compared to the animal tests they seek to replace, and strategies now exist to adequately assess human skin irritation potential without the need to rely on animal test methods.

  19. N-acetyltransferase in human skin and keratinocytes

    NARCIS (Netherlands)

    Vogel, Tanja; Bonifas, Jutta; Wiegman, Marjon; Pas, Hendrikus; Blömeke, Brunhilde; Coenraads, Pieter Jan; Schuttelaar, Marie-Louise

    Background: N-acetyltransferase 1 (NAT1) mediated Nacetylation in human skin and keratinocytes is an important detoxification pathway for aromatic amines including the strong sensitizer para-phenylenediamine (PPD), an important component of oxidative hair dyes. Objectives: Human skin and

  20. Histamine suppresses epidermal keratinocyte differentiation and impairs skin barrier function in a human skin model

    OpenAIRE

    Gschwandtner, M; Mildner, M.; Mlitz, V; Gruber, F; Eckhart, L; Werfel, T.; Gutzmer, R.; Elias, P M; Tschachler, E.

    2012-01-01

    Background Defects in keratinocyte differentiation and skin barrier are important features of inflammatory skin diseases like atopic dermatitis. Mast cells and their main mediator histamine are abundant in inflamed skin and thus may contribute to disease pathogenesis. Methods Human primary keratinocytes were cultured under differentiation-promoting conditions in the presence and absence of histamine, histamine receptor agonists and antagonists. The expression of differentiation-associated gen...

  1. Antioxidant capacity of 3D human skin EpiDerm model: effects of skin moisturizers.

    Science.gov (United States)

    Grazul-Bilska, A T; Bilski, J J; Redmer, D A; Reynolds, L P; Abdullah, K M; Abdullah, A

    2009-06-01

    The objective of this study was to determine the effects of skin moisturizers on total antioxidant capacity (TAC) of human skin using EpiDerm model. Three different skin moisturizers containing antioxidant ingredients (samples 1-3) or aloe vera extract were topically applied to EpiDerm units and incubated for 2 and 24 h to determine acute and longer-term effects of applied samples on TAC and glutathione peroxidase activity in medium and/or homogenized skin tissues. Total antioxidant capacity in medium and skin homogenates was enhanced (P affect TAC. Glutathione peroxidase activity was enhanced (P < 0.0001) in medium and skin homogenates by sample 2 but not by any other sample. These data demonstrate high potential of gel and cream (samples 2 and 3) containing antioxidant ingredients in enhancing antioxidant capacity of EpiDerm which will likely contribute to overall skin health. Results of this experiment will help to better understand mechanisms of effects of skin moisturizers containing antioxidant ingredients on skin function at the tissue level and to establish effective strategies for skin protection and clinical treatments of skin disorders and possibly healing wounds.

  2. Multiphoton STED and FRET in human skin: Resolving the skin barrier

    DEFF Research Database (Denmark)

    Antonescu, Irina; Dreier, Jes; Brewer, Jonathan R.

    excited STED and Forster Resonance Energy Transfer (FRET) microscopy to probe the structure of human skin. Super resolution optical microscopy enables resolving structures in the skin below to 60 nm allowing visualization of the stratum corneum intercellular lipid matrix and individual proteins...

  3. Modelling and verification of melanin concentration on human skin type

    CSIR Research Space (South Africa)

    Karsten, AE

    2012-03-01

    Full Text Available /or in vitro and elucidated the melanosomal differences between 5 the different skin types. Meinhardt et al (9) measured the absorption spectra of in vivo human 6 skin from the lighter skin types before and after exposure to natural UV radiation, while Wan 7... et al (10) measured the epidermal (including the Stratum corneum) transmittance of in vitro 8 light and dark coloured human skin over the UVA, UVB and visible wavelength ranges. 9 None of these studies however specifically determined epidermal...

  4. Nanocrystalline titanium dioxide and magnesium oxide in vitro dermal absorption in human skin.

    Science.gov (United States)

    van der Merwe, Deon; Tawde, Snehal; Pickrell, John A; Erickson, Larry E

    2009-01-01

    The dermal absorption potential of a nanocrystalline magnesium oxide (MgO) and titanium dioxide (TiO(2)) mixture in dermatomed human skin was assessed in vitro using Bronaugh-type flow-through diffusion cells. Nanocrystalline material was applied to the skin surface at a dose rate of 50 mg/cm(2) as a dry powder, as a water suspension, and as a water/surfactant (sodium lauryl sulfate) suspension, for 8 hours. Dermal absorption of nanocrystalline MgO and TiO(2) through human skin with intact, functional stratum corneum was not detectable under the conditions of this experiment.

  5. Adaptation of human skin color in various populations.

    Science.gov (United States)

    Deng, Lian; Xu, Shuhua

    2018-01-01

    Skin color is a well-recognized adaptive trait and has been studied extensively in humans. Understanding the genetic basis of adaptation of skin color in various populations has many implications in human evolution and medicine. Impressive progress has been made recently to identify genes associated with skin color variation in a wide range of geographical and temporal populations. In this review, we discuss what is currently known about the genetics of skin color variation. We enumerated several cases of skin color adaptation in global modern humans and archaic hominins, and illustrated why, when, and how skin color adaptation occurred in different populations. Finally, we provided a summary of the candidate loci associated with pigmentation, which could be a valuable reference for further evolutionary and medical studies. Previous studies generally indicated a complex genetic mechanism underlying the skin color variation, expanding our understanding of the role of population demographic history and natural selection in shaping genetic and phenotypic diversity in humans. Future work is needed to dissect the genetic architecture of skin color adaptation in numerous ethnic minority groups around the world, which remains relatively obscure compared with that of major continental groups, and to unravel the exact genetic basis of skin color adaptation.

  6. Using infrared and Raman microspectroscopies to compare ex vivo involved psoriatic skin with normal human skin

    Science.gov (United States)

    Leroy, Marie; Lefèvre, Thierry; Pouliot, Roxane; Auger, Michèle; Laroche, Gaétan

    2015-06-01

    Psoriasis is a chronic dermatosis that affects around 3% of the world's population. The etiology of this autoimmune pathology is not completely understood. The barrier function of psoriatic skin is known to be strongly altered, but the structural modifications at the origin of this dysfunction are not clear. To develop strategies to reduce symptoms of psoriasis or adequate substitutes for modeling, a deep understanding of the organization of psoriatic skin at a molecular level is required. Infrared and Raman microspectroscopies have been used to obtain direct molecular-level information on psoriatic and healthy human skin biopsies. From the intensities and positions of specific vibrational bands, the lipid and protein distribution and the lipid order have been mapped in the different layers of the skin. Results showed a similar distribution of lipids and collagen for normal and psoriatic human skin. However, psoriatic skin is characterized by heterogeneity in lipid/protein composition at the micrometer scale, a reduction in the definition of skin layer boundaries and a decrease in lipid chain order in the stratum corneum as compared to normal skin. A global decrease of the structural organization is exhibited in psoriatic skin that is compatible with an alteration of its barrier properties.

  7. Influence of different cosmetic formulations on the human skin barrier.

    Science.gov (United States)

    Heinrich, K; Heinrich, U; Tronnier, H

    2014-01-01

    The human skin barrier is an important part of the skin's intactness and its functionality is a precondition for healthy skin. Ingredients in cosmetic formulations, especially penetration enhancers, can influence this barrier function as they transport active agents into deeper skin layers. In this study different cosmetic formulations were tested by 60 healthy female volunteers over a period of 4 weeks. The skin hydration and barrier function before and during the application were measured. Significant changes in both parameters were determined. A negative influence on the barrier function by penetration enhancers could be observed, but it was also found that lamellar lipid structures (DermaMembranSysteme®, DMS®) are able to enhance the skin barrier. Both penetration enhancers as well as DMS can increase skin hydration. © 2014 S. Karger AG, Basel.

  8. Acute effects of cold therapy on knee skin surface temperature: gel pack versus ice bag

    OpenAIRE

    Breslin, Matthew; Lam, Patrick; Murrell, George A C

    2015-01-01

    Background To our knowledge there has been no research that has compared the effectiveness of two popular cold therapy modalities applied to healthy human knees, with a surgical dressing, over a 4?h period. Hypothesis To determine whether gel packs are more effective than ice bags at reducing skin surface temperature in humans. Study design This was a randomised, repeated measures crossover study, which included nine healthy participants. Level of evidence Level 2. Methods Two cold therapy mo...

  9. Are newly discovered drivers of immune-mediated skin disorders expressed in normal skin regenerating from standardized surface injury?

    NARCIS (Netherlands)

    Hendriks, A.G.M.; Keijsers, R.R.M.C.; Seyger, M.M.B.; Erp, P.E.J. van; Kerkhof, P.C.M. van de

    2014-01-01

    Background: In healthy skin, tape stripping induces a transient wave of histological changes resembling immune-mediated skin diseases, such as psoriasis. The response to surface trauma may harbor mechanisms which are also relevant to the development of Koebner-positive skin disorders. However,

  10. Tactile-direction-sensitive and stretchable electronic skins based on human-skin-inspired interlocked microstructures.

    Science.gov (United States)

    Park, Jonghwa; Lee, Youngoh; Hong, Jaehyung; Lee, Youngsu; Ha, Minjeong; Jung, Youngdo; Lim, Hyuneui; Kim, Sung Youb; Ko, Hyunhyub

    2014-12-23

    Stretchable electronic skins with multidirectional force-sensing capabilities are of great importance in robotics, prosthetics, and rehabilitation devices. Inspired by the interlocked microstructures found in epidermal-dermal ridges in human skin, piezoresistive interlocked microdome arrays are employed for stress-direction-sensitive, stretchable electronic skins. Here we show that these arrays possess highly sensitive detection capability of various mechanical stimuli including normal, shear, stretching, bending, and twisting forces. Furthermore, the unique geometry of interlocked microdome arrays enables the differentiation of various mechanical stimuli because the arrays exhibit different levels of deformation depending on the direction of applied forces, thus providing different sensory output patterns. In addition, we show that the electronic skins attached on human skin in the arm and wrist areas are able to distinguish various mechanical stimuli applied in different directions and can selectively monitor different intensities and directions of air flows and vibrations.

  11. Experiment Evaluation of Skin Friction Drag by Surface Tailoring

    Science.gov (United States)

    Manigandan, S.; Gopal krishna, K.; Gagan Kumar, K.; Gunasekar, P.; Nithya, S.

    2017-08-01

    Reduction of drag is an important role of aerodynamic specialist in real time world. The performance of forward moving object improved when the drag is reduced. Skin friction drag caused when the fluid tending to shear along the surface of the body and it is dependent on energy expenditure. Initial research concluded that nearly 20 to 40% of total drag is skin friction drag, based on flight forward velocity. This means a lot of fuel burned. In this paper we investigate a methodology to reduce the skin friction drag by implementing different kinds of exterior treatments. The ideology inspired from the world fastest moving oceanic creature. Structures are fabricated based on the replica of scales of the oceanic creature. The outer skin of the aerofoil NACA0012 is modified like shark scales. Then it is tested using open type sub sonic wind tunnel. In addition to that, the leading edge thickness effect also studied. The turbulent flow phenomenon is validated at different velocities and compared with numerical results using STAR CCM+. From the plots and graphical results, it is found that the skin friction drag is generated less due to reduction of transverse shear stress present in turbulent flow and skin friction drag depends on boundary layer thickness and on the percentage of chord of flow separation. In addition to this, the result delivers that the ordinary polished surface produces more drag than the modified scales. The outlook of this technology is excrescence for different applications. This open section wind tunnel testing produces 10-15% reduction in drag and can be turn to high values when the experiment is conducted in closed section wind tunnel with real time atmospheric conditions, which can be done as a future work.

  12. Enhancement of Human Cheek Skin Texture by Acacia Nilotica Bark ...

    African Journals Online (AJOL)

    ... < 0.05) and the texture parameter of energy showed significant increase (p < 0.05). Conclusion: Our findings indicate that the cream containing 3 % Acacia nilotica bark extract possesses anti-aging effect and improves skin surface appearance.. Keywords: Acacia nilotica, Cream, Visioscan VC 98, Skin texture, Anti-aging ...

  13. Skin surface brachytherapy: A survey of contemporary practice patterns.

    Science.gov (United States)

    Likhacheva, Anna O; Devlin, Phillip M; Shirvani, Shervin M; Barker, Christopher A; Beron, Phillip; Bhatnagar, Ajay; Doggett, Stephen W; Hochman, Lawrence; Hsu, Charles; Kasper, Michael; Keisch, Martin; Mutyala, Subhakar; Prestidge, Bradley; Rodriguez Villalba, Silvia; Shukla, Vershalee; Sundararaman, Srinath; Kamrava, Mitchell

    The aim of this study was to define current patterns of care among radiation oncologists who use skin surface brachytherapy for the treatment of cutaneous squamous cell carcinoma (cSCC) and basal cell carcinoma (BCC) in academic and community settings. A 30-question electronic survey was administered to clinician members of the American Brachytherapy Society. The respondents were asked to provide details regarding their clinical practice and their approach to skin surface brachytherapy. A total of 16 surveys were returned. Among the respondents, aggregate experience varied from 8 to 1800 cases. Most preferred brachytherapy over external beam radiation because of shorter treatment course, conformality of treatment for irregular or curved targets, and shallow dose deposition. Of the total, 60% of respondents routinely estimated lesion depth via ultrasound before initiating treatment. Treatment margin on gross disease varied widely (range, 3-15 mm; median, 5 mm). Hypofractionation was the preferred dose schedule. Prescribed doses ranged from 30 Gy in five fractions to 64 Gy in 32 fractions (EQD2, 40 Gy-65 Gy). There was a tendency to increase the number of fractions for larger targets, although some used the same fractionation regardless of anatomic location or lesion size. There was no consensus on dosimetric constraints, and some respondents reported cases of severe toxicity, particularly when treating the pretibial skin. This pattern of care study suggests that skin brachytherapy can be a convenient and safe tool for treatment of BCC and cSCC. Prospective trials and the development of expert consensus guidelines would be beneficial for optimizing skin surface brachytherapy and reducing practice variation. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  14. Measurement of interstitial cetirizine concentrations in human skin

    DEFF Research Database (Denmark)

    Petersen, Lars Jelstrup; Church, M K; Rihoux, J P

    1999-01-01

    BACKGROUND: The purpose of the present study was to measure the concentrations of cetirizine in the extracellular water compartment in intact human skin and assess simultaneously inhibition of histamine-induced wheal and flare reactions. METHODS: Skin cetirizine levels were collected by the micro...

  15. Variables influencing the frictional behaviour of in vivo human skin

    NARCIS (Netherlands)

    Veijgen, N.K.; Masen, Marc Arthur; van der Heide, Emile

    2013-01-01

    In the past decades, skin friction research has focused on determining which variables are important to affect the frictional behaviour of in vivo human skin. Until now, there is still limited knowledge on these variables. This study has used a large dataset to identify the effect of variables on

  16. Comparison of the Skin Penetration of 3 Metabolically Stable Chemicals Using Fresh and Frozen Human Skin.

    Science.gov (United States)

    Jacques-Jamin, Carine; Duplan, Hélène; Rothe, Helga; Vaillant, Ophelie; Eilstein, Joan; Grégoire, Sebastien; Cubberley, Richard; Lange, Daniela; Ellison, Corie; Klaric, Martina; Hewitt, Nicola; Schepky, Andreas

    2017-01-01

    The Cosmetics Europe ADME Task Force is developing in vitro and in silico tools for predicting skin and systemic concentrations after topical application of cosmetic ingredients. There are conflicting reports as to whether the freezing process affects the penetration of chemicals; therefore, we evaluated whether the storage of human skin used in our studies (8-12 weeks at -20°C) affected the penetration of model chemicals. Finite doses of trans-cinnamic acid (TCA), benzoic acid (BA), and 6-methylcoumarin (6MC) (non-volatile, non-protein reactive and metabolically stable in skin) were applied to fresh and thawed frozen skin from the same donors. The amounts of chemicals in different skin compartments were analysed after 24 h. Although there were some statistical differences in some parameters for 1 or 2 donors, the penetration of TCA, BA, and 6MC was essentially the same in fresh and frozen skin, i.e., there were no biologically relevant differences in penetration values. Statistical differences that were evident indicated that penetration was marginally lower in frozen than in fresh skin, indicating that the barrier function of the skin was not lost. The penetration of the 3 chemicals was essentially unaffected by freezing the skin at -20°C for up to 12 weeks. © 2017 S. Karger AG, Basel.

  17. Formation of a protection film on the human skin by microparticles

    Science.gov (United States)

    Lademann, J.; Schanzer, S.; Richter, H.; Antoniou, C.; Knorr, F.; Sterry, W.; Patzelt, A.

    2008-09-01

    Laser scanning microscopy and tape stripping, in combination with optical methods, were used to analyze the distribution and penetration of a barrier cream into the horny layer (stratum corneum) of the human skin under in vivo conditions. The barrier cream contained microparticles of 10 - 100 μm loaded with antioxidant substances. The cream was designed for protection of the skin surface against the destructive action of free radicals, produced by systemically applied chemotherapeutic agents reaching the skin surface via the sweat. Both methods were able to demonstrate that the barrier cream was distributed homogeneously on the skin surface forming a protection film. A penetration into deeper parts of the stratum corneum (SC) was not observed.

  18. The moisturizing effects of glycolipid biosurfactants, mannosylerythritol lipids, on human skin.

    Science.gov (United States)

    Yamamoto, Shuhei; Morita, Tomotake; Fukuoka, Tokuma; Imura, Tomohiro; Yanagidani, Shusaku; Sogabe, Atsushi; Kitamoto, Dai; Kitagawa, Masaru

    2012-01-01

    Glycolipid biosurfactants, such as mannosylerythritol lipids (MELs), are produced by different yeasts belonging to the genus Pseudozyma and have been attracting much attention as new cosmetic ingredients owing to their unique liquid-crystal-forming and moisturizing properties. In this study, the effects of different MEL derivatives on the skin were evaluated in detail using a three-dimensional cultured human skin model and an in vivo human study. The skin cells were cultured and treated with sodium dodecyl sulfate (SDS), and the effects of different lipids on the SDS-damaged cells were evaluated on the basis of cell viability. Most MEL derivatives efficiently recovered the viability of the cells and showed high recovery rates (over 80%) comparable with that of natural ceramide. It is interesting that the recovery rate with MEL-A prepared from olive oil was significantly higher than that of MEL-A prepared from soybean oil. The water retention properties of MEL-B were further investigated on human forearm skin in a preliminary study. Compared with the control, the aqueous solution of MEL-B (5 wt%) was estimated to considerably increase the stratum corneum water content in the skin. Moreover, perspiration on the skin surface was clearly suppressed by treatment with the MEL-B solution. These results suggest that MELs are likely to exhibit a high moisturizing action, by assisting the barrier function of the skin. Accordingly, the yeast glycolipids have a strong potential as a new ingredient for skin care products.

  19. Reproducible pattern of microRNA in normal human skin

    DEFF Research Database (Denmark)

    Holst, Line; Kaczkowski, Bogumil; Gniadecki, Robert

    2010-01-01

    MicroRNAs (miRNAs) regulate cell growth, differentiation and apoptosis via specific targeting of messenger RNA (mRNA). Aberrant mRNA expression contributes to pathological processes such as carcinogenesis. To take advantage of miRNA profiling in skin disease it is essential to investigate miRNA...... expression pattern in normal human skin. Here we investigated miRNA expression profiles from skin biopsies of 8 healthy volunteers taken from sun protected and mildly photo damaged skin using the modified protocol for miRNA extraction. We were able to show a constant pattern of miRNA expression between...... different individuals. We did not find any significant differences in miRNA expression between sun protected and mildly photodamaged skin. These results may be valuable for future design of studies on miRNA expression in skin disease....

  20. Perception-based 3D tactile rendering from a single image for human skin examinations by dynamic touch.

    Science.gov (United States)

    Kim, K; Lee, S

    2015-05-01

    Diagnosis of skin conditions is dependent on the assessment of skin surface properties that are represented by more tactile properties such as stiffness, roughness, and friction than visual information. Due to this reason, adding tactile feedback to existing vision based diagnosis systems can help dermatologists diagnose skin diseases or disorders more accurately. The goal of our research was therefore to develop a tactile rendering system for skin examinations by dynamic touch. Our development consists of two stages: converting a single image to a 3D haptic surface and rendering the generated haptic surface in real-time. Converting to 3D surfaces from 2D single images was implemented with concerning human perception data collected by a psychophysical experiment that measured human visual and haptic sensibility to 3D skin surface changes. For the second stage, we utilized real skin biomechanical properties found by prior studies. Our tactile rendering system is a standalone system that can be used with any single cameras and haptic feedback devices. We evaluated the performance of our system by conducting an identification experiment with three different skin images with five subjects. The participants had to identify one of the three skin surfaces by using a haptic device (Falcon) only. No visual cue was provided for the experiment. The results indicate that our system provides sufficient performance to render discernable tactile rendering with different skin surfaces. Our system uses only a single skin image and automatically generates a 3D haptic surface based on human haptic perception. Realistic skin interactions can be provided in real-time for the purpose of skin diagnosis, simulations, or training. Our system can also be used for other applications like virtual reality and cosmetic applications. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Effect of Different Skin Penetration Promoters in Halobetasol Propionate Permeation and Retention in Human Skin

    Directory of Open Access Journals (Sweden)

    Paulina Carvajal-Vidal

    2017-11-01

    Full Text Available Halobetasol propionate (HB is a potent synthetic corticosteroid used against inflammatory skin diseases, such as dermatitis, eczema, and psoriasis, among others. The aim of this study is to define how the presence of different skin penetration enhancers (nonane, menthone, limonene, azone, carene, decanol, linoleic acid and cetiol affects the penetration and retention in skin of HB. To determine drug penetration through skin, 5% of each promoter was used in an ex vivo system with human skin on Franz cells. The results showed that the highest permeation occurs in the presence of menthone, followed by nonane. Permeation parameters were determined. The in vivo test was assessed, and the formulation containing HB-menthone presented better anti-inflammatory efficacy. These results are useful to generate a specific treatment according to each patient’s needs, and the inflammatory characteristics of the disease.

  2. Preliminary characterization of human skin microbiome in healthy Egyptian individuals.

    Science.gov (United States)

    Ramadan, M; Solyman, S; Taha, M; Hanora, A

    2016-07-31

    Human skin is a large, complex ecosystem that harbors diverse microbial communities. The rapid advances in molecular techniques facilitate the exploration of skin associated bacterial populations. The objective of this study was to perform a preliminary characterization of skin associated bacterial populations in Egyptian individuals. Samples were collected from five healthy subjects from two skin sites; Antecubital Fossa (AF) and Popliteal Fossa (PF). Genomic DNA was extracted and used to amplify bacterial 16S rRNA genes which were sequenced on Illumina MiSeq platform. The two sites showed distinct diversity where PF was more diverse than AF. Taxonomic analysis of sequences revealed four main phyla Proteobacteria, Firmicutes, Actinobacteria and Deinococcus-Thermus, with Proteobacteria presenting the highest diversity. Klebsiella, Bacillus, Pseudomonas and Escherichia were the most predominant genera. Our data suggest that environmental factors can shape the composition of the skin microbiome in certain geographical regions. This study presents a new insight for subsequent analyses of human microbiome in Egypt.

  3. Fatty acids penetration into human skin ex vivo: A TOF-SIMS analysis approach.

    Science.gov (United States)

    Čižinauskas, Vytis; Elie, Nicolas; Brunelle, Alain; Briedis, Vitalis

    2017-03-02

    Linoleic, oleic, palmitoleic, palmitic, and stearic fatty acids (FAs) are commonly used in dermatological formulations. They differ by their structure, presence in the skin, and mode of application in pharmaceuticals and cosmetics compounding. These FAs are also known as chemical penetration enhancers, but their mechanisms of penetration enhancement and effect on barrier characteristics of the skin require additional study. In this study, the authors conducted an ex vivo analysis of the distribution of lipid components in the epidermis and dermis of human skin after applying individual FAs. The goal was to elucidate possible mechanisms of penetration enhancement and FA effects on barrier characteristics of the skin. FA penetration studies were conducted ex vivo on human skin and time-of-flight secondary ion mass spectrometry (TOF-SIMS) bioimaging analysis was performed to visualize and analyze distribution of FAs in skin sections. The current study demonstrated that TOF-SIMS imaging was effective in visualizing the distribution of linoleic, oleic, palmitoleic, palmitic, and stearic acid in the human skin ex vivo after the skin penetration experiment of individual FAs. The integration of the obtained TOF-SIMS images allowed a semiquantitative comparison of the effects induced by individual FA applications on the human skin ex vivo. FAs showed varying abilities to penetrate the skin and disorder the FAs within the skin, based on their structures and physicochemical properties. Linoleic acid penetrated the skin and changed the distribution of all the analyzed FAs. Skin treatment with palmitoleic or oleic acid increased the amounts of singular FAs in the skin. Penetration of saturated FAs was low, but it increased the detected amounts of linoleic acid in both skin layers. The results indicate that application of FAs on the skin surface induce redistribution of native FAs not only in the stratum corneum layer of epidermis but also in the lipid content of full epidermis

  4. Tribological behaviour of skin equivalents and ex-vivo human skin against the material components of artificial turf in sliding

    NARCIS (Netherlands)

    Morales Hurtado, Marina; Peppelman, P.; Zeng, Xiangqiong; van Erp, P.E.J.; van der Heide, Emile

    2016-01-01

    This research aims to analyse the interaction of three artificial skin equivalents and human skin against the main material components of artificial turf. The tribological performance of Lorica, Silicone Skin L7350 and a recently developed Epidermal Skin Equivalent (ESE) were studied and compared to

  5. Vehicle effects on human stratum corneum absorption and skin penetration.

    Science.gov (United States)

    Zhang, Alissa; Jung, Eui-Chang; Zhu, Hanjiang; Zou, Ying; Hui, Xiaoying; Maibach, Howard

    2017-05-01

    This study evaluated the effects of three vehicles-ethanol (EtOH), isopropyl alcohol (IPA), and isopropyl myristate (IPM)-on stratum corneum (SC) absorption and diffusion of the [(14)C]-model compounds benzoic acid and butenafine hydrochloride to better understand the transport pathways of chemicals passing through and resident in SC. Following application of topical formulations to human dermatomed skin for 30 min, penetration flux was observed for 24 h post dosing, using an in vitro flow-through skin diffusion system. Skin absorption and penetration was compared to the chemical-SC (intact, delipidized, or SC lipid film) binding levels. A significant vehicle effect was observed for chemical skin penetration and SC absorption. IPA resulted in the greatest levels of intact SC/SC lipid absorption, skin penetration, and total skin absorption/penetration of benzoic acid, followed by IPM and EtOH, respectively. For intact SC absorption and total skin absorption/penetration of butenafine, the vehicle that demonstrated the highest level of sorption/penetration was EtOH, followed by IPA and IPM, respectively. The percent doses of butenafine that were absorbed in SC lipid film and penetrated through skin in 24 h were greatest for IPA, followed by EtOH and IPM, respectively. The vehicle effect was consistent between intact SC absorption and total chemical skin absorption and penetration, as well as SC lipid absorption and chemical penetration through skin, suggesting intercellular transport as a main pathway of skin penetration for model chemicals. These results suggest the potential to predict vehicle effects on skin permeability with simple SC absorption assays. As decontamination was applied 30 min after chemical exposure, significant vehicle effects on chemical SC partitioning and percutaneous penetration also suggest that skin decontamination efficiency is vehicle dependent, and an effective decontamination method should act on chemical solutes in the lipid domain.

  6. Histamine suppresses epidermal keratinocyte differentiation and impairs skin barrier function in a human skin model

    Science.gov (United States)

    Gschwandtner, M; Mildner, M; Mlitz, V; Gruber, F; Eckhart, L; Werfel, T; Gutzmer, R; Elias, P M; Tschachler, E

    2013-01-01

    Background Defects in keratinocyte differentiation and skin barrier are important features of inflammatory skin diseases like atopic dermatitis. Mast cells and their main mediator histamine are abundant in inflamed skin and thus may contribute to disease pathogenesis. Methods Human primary keratinocytes were cultured under differentiation-promoting conditions in the presence and absence of histamine, histamine receptor agonists and antagonists. The expression of differentiation-associated genes and epidermal junction proteins was quantified by real-time PCR, Western blot, and immunofluorescence labeling. The barrier function of human skin models was tested by the application of biotin as tracer molecule. Results The addition of histamine to human keratinocyte cultures and organotypic skin models reduced the expression of the differentiation-associated proteins keratin 1/10, filaggrin, and loricrin by 80–95%. Moreover, the addition of histamine to skin models resulted in the loss of the granular layer and thinning of the epidermis and stratum corneum by 50%. The histamine receptor H1R agonist, 2-pyridylethylamine, suppressed keratinocyte differentiation to the same extent as did histamine. Correspondingly, cetirizine, an antagonist of H1R, virtually abrogated the effect of histamine. The expression of tight junction proteins zona occludens-1, occludin, claudin-1, and claudin-4, as well as that of desmosomal junction proteins corneodesmosin and desmoglein-1, was down-regulated by histamine. The tracer molecule biotin readily penetrated the tight junction barrier of skin cultures grown in the presence of histamine, while their diffusion was completely blocked in nontreated controls. Conclusions Our findings suggest a new mechanism by which mast cell activation and histamine release contribute to skin barrier defects in inflammatory skin diseases. PMID:23157658

  7. Coverage error of commercial skin pigments as compared to human facial skin tones.

    Science.gov (United States)

    Hungerford, Elizabeth; Beatty, Mark W; Marx, David B; Simetich, Bobby; Wee, Alvin G

    2013-11-01

    It is unknown if present-day pigments used for intrinsic colouration of maxillofacial prostheses are representative of human facial skin tones. This study's purpose was to measure L*a*b* values of pigmented elastomers coloured by eleven skin tone pigments and determine coverage error (CE) when the pigments were compared to human facial lip and nose colour data. 11 skin tone pigments were combined at 0.1%, 1% and 10% by weight with A-2186 elastomer (n=3). L*a*b* values were measured with a spectrophotometer and group means were used to calculate ΔE* colour differences with each L*a*b* value obtained for human nose and lip. Pigmented elastomer CEs were calculated for nose and lip. Results were compared to CEs for proposed shade guide colours obtained from clustering analyses of facial skin colours. L* values of pigmented elastomers generally were higher than those measured for nose and lip, whereas a* values were lower. CEs for pigmented elastomers were higher than those obtained from the proposed shade guide obtained from clustered skin measurements. Overall, the current commercial elastomers appeared to be too white and not red enough to adequately match the skin tones of the subject population. Adjustments must be made to the existing pigmenting system in order to adequately match the skin colours of the study population. The creation of a shade guide and a collection of intrinsic pigments representing the realm of human facial skin colours would greatly decrease the time a patient must sit while the clinician is obtaining an acceptable colour match for the silicone to be used for processing the final prosthesis, thereby increasing both patient satisfaction and clinician productivity. Published by Elsevier Ltd.

  8. Effects of hypobaric pressure on human skin: implications for cryogen spray cooling (part II).

    Science.gov (United States)

    Aguilar, Guillermo; Franco, Walfre; Liu, Jie; Svaasand, Lars O; Nelson, J Stuart

    2005-02-01

    Clinical results have demonstrated that dark purple port wine stain (PWS) birthmarks respond favorably to laser induced photothermolysis after the first three to five treatments. Nevertheless, complete blanching is rarely achieved and the lesions stabilize at a red-pink color. In a feasibility study (Part I), we showed that local hypobaric pressure on PWS human skin prior to laser irradiation induced significant lesion blanching. The objective of the present study (Part II) is to investigate the effects of hypobaric pressures on the efficiency of cryogen spray cooling (CSC), a technique that assists laser therapy of PWS and other dermatoses. Experiments were carried out within a suction cup and vacuum chamber to study the effect of hypobaric pressure on the: (1) interaction of cryogen sprays with human skin; (2) spray atomization; and (3) thermal response of a model skin phantom. A high-speed camera was used to acquire digital images of spray impingement on in vivo human skin and spray cones generated at different hypobaric pressures. Subsequently, liquid cryogen was sprayed onto a skin phantom at atmospheric and 17, 34, 51, and 68 kPa (5, 10, 15, and 20 in Hg) hypobaric pressures. A fast-response temperature sensor measured sub-surface phantom temperature as a function of time. Measurements were used to solve an inverse heat conduction problem to calculate surface temperatures, heat flux, and overall heat extraction at the skin phantom surface. Under hypobaric pressures, cryogen spurts did not produce skin indentation and only minimal frost formation. Sprays also showed shorter jet lengths and better atomization. Lower minimum surface temperatures and higher overall heat extraction from skin phantoms were reached. The combined effects of hypobaric pressure result in more efficient cryogen evaporation that enhances heat extraction and, therefore, improves the epidermal protection provided by CSC. (c) 2005 Wiley-Liss, Inc.

  9. From frog integument to human skin: dermatological perspectives from frog skin biology.

    Science.gov (United States)

    Haslam, Iain S; Roubos, Eric W; Mangoni, Maria Luisa; Yoshizato, Katsutoshi; Vaudry, Hubert; Kloepper, Jennifer E; Pattwell, David M; Maderson, Paul F A; Paus, Ralf

    2014-08-01

    For over a century, frogs have been studied across various scientific fields, including physiology, embryology, neuroscience, (neuro)endocrinology, ecology, genetics, behavioural science, evolution, drug development, and conservation biology. In some cases, frog skin has proven very successful as a research model, for example aiding in the study of ion transport through tight epithelia, where it has served as a model for the vertebrate distal renal tubule and mammalian epithelia. However, it has rarely been considered in comparative studies involving human skin. Yet, despite certain notable adaptations that have enabled frogs to survive in both aquatic and terrestrial environments, frog skin has many features in common with human skin. Here we present a comprehensive overview of frog (and toad) skin ontogeny, anatomy, cytology, neuroendocrinology and immunology, with special attention to its unique adaptations as well as to its similarities with the mammalian integument, including human skin. We hope to provide a valuable reference point and a source of inspiration for both amphibian investigators and mammalian researchers studying the structural and functional properties of the largest organ of the vertebrate body. © 2013 The Authors. Biological Reviews © 2013 Cambridge Philosophical Society.

  10. Influence of two different IR radiators on the antioxidative potential of the human skin

    Science.gov (United States)

    Darvin, M. E.; Patzelt, A.; Meinke, M.; Sterry, W.; Lademann, J.

    2009-03-01

    Resonance Raman spectroscopy was used for the fast in vivo detection of the concentration of carotenoid antioxidant substances such as beta-carotene and lycopene in human skin and for the measurement of their degradation dynamics, subsequent to infrared (IR) irradiation emitted by two different IR radiators applied at the same power density. One of the radiators was equipped with a water filter in front of the radiation source (WIRA) and the other was a usual broadband system without a water filter (standard IR radiator - SIR). It was found that the SIR exerted a higher influence on the degradation of carotenoids in the skin than the WIRA. Furthermore, all twelve volunteers who participated in the study felt that the irradiation with the SIR was disagreeably warmer on the skin surface compared to the WIRA, in spite of the same power density values for both radiators on the skin surface. The average degradation magnitude of the carotenoids in the skin of all volunteers after an IR irradiation was determined at 23% for WIRA and 33% for the SIR. A correlation (R2 ~ 0.6) was found between the individual level of carotenoids in the skin of the volunteers and the magnitude of degradation of the carotenoids for both IR radiators. Taking the previous investigations into consideration, which clearly showed production of free radicals in the skin subsequent to IR irradiation, it can be concluded that during the application of WIRA irradiation on the skin, fewer radicals are produced in comparison to the SIR.

  11. Effectiveness of hand washing on the removal of iron oxide nanoparticles from human skin ex vivo.

    Science.gov (United States)

    Lewinski, Nastassja A; Berthet, Aurélie; Maurizi, Lionel; Eisenbeis, Antoine; Hopf, Nancy B

    2017-08-01

    In this study, the effectiveness of washing with soap and water in removing nanoparticles from exposed skin was investigated. Dry, nanoscale hematite (α-Fe2O3) or maghemite (γ-Fe2O3) powder, with primary particle diameters between 20-30 nm, were applied to two samples each of fresh and frozen ex vivo human skin in two independent experiments. The permeation of nanoparticles through skin, and the removal of nanoparticles after washing with soap and water were investigated. Bare iron oxide nanoparticles remained primarily on the surface of the skin, without penetrating beyond the stratum corneum. Skin exposed to iron oxide nanoparticles for 1 and 20 hr resulted in removal of 85% and 90%, respectively, of the original dose after washing. In the event of dermal exposure to chemicals, removal is essential to avoid potential local irritation or permeation across skin. Although manufactured at an industrial scale and used extensively in laboratory experiments, limited data are available on the removal of engineered nanoparticles after skin contact. Our finding raises questions about the potential consequences of nanoparticles remaining on the skin and whether alternative washing methods should be proposed. Further studies on skin decontamination beyond use of soap and water are needed to improve the understanding of the potential health consequences of dermal exposure to nanoparticles.

  12. In-vitro percutaneous absorption of losartan potassium in human skin and prediction of human skin permeability

    Directory of Open Access Journals (Sweden)

    Petkar K.C.

    2007-05-01

    Full Text Available This study describes the feasibility of transdermal controlled administration of Losartan potassium (LP across human cadaver skin. Study also defines the influence of capsaicin, sex and site of application on permeation characteristics and determined an appropriate animal model for human skin permeability. The permeation of LP of various formulations was studied using Keshary-Chein diffusion cell. Optimized controlled formulation (without capsaicin released 42.17% (±1.85 of LP in 12 hr whereas treatment formulation (with capsaicin 0.028 % w/v released 48.94% (±1.71 of LP with significant difference on null hypothesis. Influence of sex showed statistically significant difference for permeation of LP through male and female rats, as well as male and female mice across both the abdominal and dorsal sides of the skin (p<0.05. Similarly statistically significant differences were noted for permeation of LP across male and female mice abdomen-dorsal, but not for male rat abdomen-dorsal and female rat abdomen-dorsal. Furthermore, in-vitro permeation of LP across human skin was compared with the permeation across rat and mice skins. Male rat and male mice dorsal skin was found to have closer permeability characteristics to human than other skin membranes, but the Factor of Difference values were < 3 for all membranes which were used suggesting the membranes are good models for human skin permeability. In conclusion simple transdermal adhesive patches formulations incorporating high molecular weight of LP can deliver a dose in-vivo and proposed model skin membranes can be utilized for future pharmacokineic and toxicokinetic studies as well as metabolism studies of LP

  13. Human Skin 3D Bioprinting Using Scaffold-Free Approach.

    Science.gov (United States)

    Pourchet, Léa J; Thepot, Amélie; Albouy, Marion; Courtial, Edwin J; Boher, Aurélie; Blum, Loïc J; Marquette, Christophe A

    2017-02-01

    Organ in vitro synthesis is one of the last bottlenecks between tissue engineering and transplantation of synthetic organs. Bioprinting has proven its capacity to produce 3D objects composed of living cells but highly organized tissues such as full thickness skin (dermis + epidermis) are rarely attained. The focus of the present study is to demonstrate the capability of a newly developed ink formulation and the use of an open source printer, for the production of a really complete skin model. Proofs are given through immunostaining and electronic microscopy that the bioprinted skin presents all characteristics of human skin, both at the molecular and macromolecular level. Finally, the printability of large skin objects is demonstrated with the printing of an adult-size ear. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Oxidative Stress in Aging Human Skin

    Science.gov (United States)

    Rinnerthaler, Mark; Bischof, Johannes; Streubel, Maria Karolin; Trost, Andrea; Richter, Klaus

    2015-01-01

    Oxidative stress in skin plays a major role in the aging process. This is true for intrinsic aging and even more for extrinsic aging. Although the results are quite different in dermis and epidermis, extrinsic aging is driven to a large extent by oxidative stress caused by UV irradiation. In this review the overall effects of oxidative stress are discussed as well as the sources of ROS including the mitochondrial ETC, peroxisomal and ER localized proteins, the Fenton reaction, and such enzymes as cyclooxygenases, lipoxygenases, xanthine oxidases, and NADPH oxidases. Furthermore, the defense mechanisms against oxidative stress ranging from enzymes like superoxide dismutases, catalases, peroxiredoxins, and GSH peroxidases to organic compounds such as L-ascorbate, α-tocopherol, beta-carotene, uric acid, CoQ10, and glutathione are described in more detail. In addition the oxidative stress induced modifications caused to proteins, lipids and DNA are discussed. Finally age-related changes of the skin are also a topic of this review. They include a disruption of the epidermal calcium gradient in old skin with an accompanying change in the composition of the cornified envelope. This modified cornified envelope also leads to an altered anti-oxidative capacity and a reduced barrier function of the epidermis. PMID:25906193

  15. Oxidative Stress in Aging Human Skin

    Directory of Open Access Journals (Sweden)

    Mark Rinnerthaler

    2015-04-01

    Full Text Available Oxidative stress in skin plays a major role in the aging process. This is true for intrinsic aging and even more for extrinsic aging. Although the results are quite different in dermis and epidermis, extrinsic aging is driven to a large extent by oxidative stress caused by UV irradiation. In this review the overall effects of oxidative stress are discussed as well as the sources of ROS including the mitochondrial ETC, peroxisomal and ER localized proteins, the Fenton reaction, and such enzymes as cyclooxygenases, lipoxygenases, xanthine oxidases, and NADPH oxidases. Furthermore, the defense mechanisms against oxidative stress ranging from enzymes like superoxide dismutases, catalases, peroxiredoxins, and GSH peroxidases to organic compounds such as L-ascorbate, α-tocopherol, beta-carotene, uric acid, CoQ10, and glutathione are described in more detail. In addition the oxidative stress induced modifications caused to proteins, lipids and DNA are discussed. Finally age-related changes of the skin are also a topic of this review. They include a disruption of the epidermal calcium gradient in old skin with an accompanying change in the composition of the cornified envelope. This modified cornified envelope also leads to an altered anti-oxidative capacity and a reduced barrier function of the epidermis.

  16. Immunoarchitectural characterization of a human skin model reconstructed in vitro

    Directory of Open Access Journals (Sweden)

    Luís Ricardo Martinhão Souto

    Full Text Available CONTEXT AND OBJECTIVE: Over the last few years, different models for human skin equivalent reconstructed in vitro (HSERIV have been reported for clinical usage and applications in research for the pharmaceutical industry. Before release for routine use as human skin replacements, HSERIV models need to be tested regarding their similarity with in vivo skin, using morphological (architectural and immunohistochemical (functional analyses. A model for HSERIV has been developed in our hospital, and our aim here was to further characterize its immunoarchitectural features by comparing them with human skin, before it can be tested for clinical use, e.g. for severe burns or wounds, whenever ancillary methods are not indicated. DESIGN AND SETTING: Experimental laboratory study, in the Skin Cell Culture Laboratory, School of Medical Sciences, Universidade Estadual de Campinas. METHODS: Histological sections were stained with hematoxylin-eosin, Masson's trichrome for collagen fibers, periodic acid-Schiff reagent for basement membrane and glycogen, Weigert-Van Gieson for elastic fibers and Fontana-Masson for melanocytes. Immunohistochemistry was used to localize cytokeratins (broad spectrum of molecular weight, AE1/AE3, high molecular weight cytokeratins (34βE12, low molecular weight cytokeratins (35βH11, cytokeratins 7 and 20, vimentin, S-100 protein (for melanocytic and dendritic cells, CD68 (KP1, histiocytes and CD34 (QBend, endothelium. RESULTS: Histology revealed satisfactory similarity between HSERIV and in vivo skin. Immunohistochemical analysis on HSERIV demonstrated that the marker pattern was similar to what is generally present in human skin in vivo. CONCLUSION: HSERIV is morphologically and functionally compatible with human skin observed in vivo.

  17. Airborne polycyclic aromatic hydrocarbons trigger human skin cells aging through aryl hydrocarbon receptor.

    Science.gov (United States)

    Qiao, Yuan; Li, Qiang; Du, Hong-Yang; Wang, Qiao-Wei; Huang, Ye; Liu, Wei

    2017-07-01

    Accumulating evidence suggests that polycyclic aromatic hydrocarbons (PAH) which adsorbed on the surface of ambient air particulate matters (PM), are the major toxic compound to cause cardiovascular and respiratory diseases, even cancer. However, its detrimental effects on human skin cell remain unclear. Here, we demonstrated that SRM1649b, a reference urban dust material of PAH, triggers human skin cells aging through cell cycle arrest, cell growth inhibition and apoptosis. Principally, SRM1649b facilitated Aryl hydrocarbon receptor (AhR) translocated into nucleus, subsequently activated ERK/MAPK signaling pathway, and upregulated aging-related genes expression. Most important, we found that AhR antagonist efficiently revert the aging of skin cells. Thus our novel findings firstly revealed the mechanism of skin aging under PAH contamination and provided potential strategy for clinical application. Copyright © 2017. Published by Elsevier Inc.

  18. Optical palpation in vivo: imaging human skin lesions using mechanical contrast

    Science.gov (United States)

    Es'haghian, Shaghayegh; Kennedy, Kelsey M.; Gong, Peijun; Sampson, David D.; McLaughlin, Robert A.; Kennedy, Brendan F.

    2015-01-01

    We demonstrate the first application of the recently proposed method of optical palpation to in vivo imaging of human skin. Optical palpation is a tactile imaging technique that probes the spatial variation of a sample's mechanical properties by producing an en face map of stress measured at the sample surface. This map is determined from the thickness of a translucent, compliant stress sensor placed between a loading element and the sample and is measured using optical coherence tomography. We assess the performance of optical palpation using a handheld imaging probe on skin-mimicking phantoms, and demonstrate its use on human skin lesions. Our results demonstrate the capacity of optical palpation to delineate the boundaries of lesions and to map the mechanical contrast between lesions and the surrounding normal skin.

  19. Comparison of skin decontamination efficacy of commercial decontamination products following exposure to VX on human skin.

    Science.gov (United States)

    Thors, L; Koch, M; Wigenstam, E; Koch, B; Hägglund, L; Bucht, A

    2017-08-01

    The decontamination efficacy of four commercially available skin decontamination products following exposure to the nerve agent VX was evaluated in vitro utilizing a diffusion cell and dermatomed human skin. The products included were Reactive Skin Decontamination Lotion (RSDL), the Swedish decontamination powder 104 (PS104), the absorbent Fuller's Earth and the aqueous solution alldecontMED. In addition, various decontamination procedures were assessed to further investigate important mechanisms involved in the specific products, e.g. decontamination removal from skin, physical removal by sponge swabbing and activation of degradation mechanisms. The efficacy of each decontamination product was evaluated 5 or 30 min after dermal application of VX (neat or diluted to 20% in water). The RSDL-lotion was superior in reducing the penetration of VX through human skin, both when exposed as neat agent and when diluted to 20% in water. Swabbing with the RSDL-sponge during 2 min revealed decreased efficacy compared to applying the RSDL-lotion directly on the skin for 30 min. Decontamination with Fuller's Earth and alldecontMED significantly reduced the penetration of neat concentration of VX through human skin. PS104-powder was insufficient for decontamination of VX at both time-points, independently of the skin contact time of PS104. The PS104-slurry (a mixture of PS104-powder and water), slightly improved the decontamination efficacy. Comparing the time-points for initiated decontamination revealed less penetrated VX for RSDL and Fuller's Earth when decontamination was initiated after 5 min compared to 30 min post-exposure, while alldecontMED displayed similar efficacy at both time-points. Decontamination by washing with water only resulted in a significant reduction of penetrated VX when washing was performed 5 min after exposure, but not when decontamination was delayed to 30 min post-exposure of neat VX. In conclusion, early initiated decontamination with the

  20. Microneedle enhanced delivery of cosmeceutically relevant peptides in human skin.

    Directory of Open Access Journals (Sweden)

    Yousuf H Mohammed

    Full Text Available Peptides and proteins play an important role in skin health and well-being. They are also found to contribute to skin aging and melanogenesis. Microneedles have been shown to substantially enhance skin penetration and may offer an effective means of peptide delivery enhancement. The aim of this investigation was to assess the influence of microneedles on the skin penetration of peptides using fluorescence imaging to determine skin distribution. In particular the effect of peptide chain length (3, 4, 5 amino acid chain length on passive and MN facilitated skin penetration was investigated. Confocal laser scanning microscopy was used to image fluorescence intensity and the area of penetration of fluorescently tagged peptides. Penetration studies were conducted on excised full thickness human skin in Franz type diffusion cells for 1 and 24 hours. A 2 to 22 fold signal improvement in microneedle enhanced delivery of melanostatin, rigin and pal-KTTKS was observed. To our knowledge this is the first description of microneedle enhanced skin permeation studies on these peptides.

  1. Skin Blood Perfusion and Oxygenation Colour Affect Perceived Human Health

    Science.gov (United States)

    Stephen, Ian D.; Coetzee, Vinet; Law Smith, Miriam; Perrett, David I.

    2009-01-01

    Skin blood perfusion and oxygenation depends upon cardiovascular, hormonal and circulatory health in humans and provides socio-sexual signals of underlying physiology, dominance and reproductive status in some primates. We allowed participants to manipulate colour calibrated facial photographs along empirically-measured oxygenated and deoxygenated blood colour axes both separately and simultaneously, to optimise healthy appearance. Participants increased skin blood colour, particularly oxygenated, above basal levels to optimise healthy appearance. We show, therefore, that skin blood perfusion and oxygenation influence perceived health in a way that may be important to mate choice. PMID:19337378

  2. A controlled laboratory comparison of 4 topical skin creams moisturizing capability on human subjects.

    Science.gov (United States)

    Young, Daniel L; Chakravarthy, Debashish

    2014-01-01

    This study compares human skin capacitance (moisture) readings after the application of 4 different, commercially available, topical skin creams. Twenty-one subjects (15 women and 6 men) aged 49.38 ± 11.02) years (mean ± SD) participated. This study was conducted in a climate-controlled laboratory on healthy human subjects. Randomized experimental study comparing 4 topical skin creams for their effect on human skin capacitance (moisture). Subject forearm skin was conditioned for 7 days prior to testing by washing with a standard soap and application of no other products. Each subject was marked with 5 test sites on the forearms. Sites on the volar surface of each subject's forearms were randomly assigned for application of 1 of 4 product pairs, consisting of a cleanser and a topical skin cream or a control site. A Corneometer was used to measure skin capacitance. Each site on the arms was cleaned and dried, tested again for moisture content, subjected to topical skin cream application, and finally tested again for moisture content. Changes were measured by subtracting the capacitance readings at baseline from values measured following topical skin cream application for each test site. The mean change in capacitance was 13.9 for product 1, 10.3 for product 3, 8.7 for product 2, 1.6 for product 4, and 0.8 for the control site. The mean capacitance change in sites treated with product 1 (13.9 ± 8.0, mean ± SD) was significantly greater than all others. There was no difference between the change in capacitance of product 2 (mean = 8.7, SD = 4.9) and product 3 (10.3 ± 7.1) t(20) = 1.081, P = .293, nor between product 4 (1.6 ± 3.9) and the control site (0.3, ± 2.2) t(20) = 0.779, P = .445. The capacitance change of products 2 and 3 was greater than that of product 4 and the control site. Commercially available topical skin creams vary in their impact on human skin capacitance. In this study, sites tested with product 1 had a greater skin capacitance reading than

  3. Human skin wetness perception: psychophysical and neurophysiological bases

    Science.gov (United States)

    Filingeri, Davide; Havenith, George

    2015-01-01

    The ability to perceive thermal changes in the surrounding environment is critical for survival. However, sensing temperature is not the only factor among the cutaneous sensations to contribute to thermoregulatory responses in humans. Sensing skin wetness (i.e. hygrosensation) is also critical both for behavioral and autonomic adaptations. Although much has been done to define the biophysical role of skin wetness in contributing to thermal homeostasis, little is known on the neurophysiological mechanisms underpinning the ability to sense skin wetness. Humans are not provided with skin humidity receptors (i.e., hygroreceptors) and psychophysical studies have identified potential sensory cues (i.e. thermal and mechanosensory) which could contribute to sensing wetness. Recently, a neurophysiological model of human wetness sensitivity has been developed. In helping clarifying the peripheral and central neural mechanisms involved in sensing skin wetness, this model has provided evidence for the existence of a specific human hygrosensation strategy, which is underpinned by perceptual learning via sensory experience. Remarkably, this strategy seems to be shared by other hygroreceptor-lacking animals. However, questions remain on whether these sensory mechanisms are underpinned by specific neuromolecular pathways in humans. Although the first study on human wetness perception dates back to more than 100 years, it is surprising that the neurophysiological bases of such an important sensory feature have only recently started to be unveiled. Hence, to provide an overview of the current knowledge on human hygrosensation, along with potential directions for future research, this review will examine the psychophysical and neurophysiological bases of human skin wetness perception. PMID:27227008

  4. Human skin hypoxia modulates cerebrovascular and autonomic functions.

    Directory of Open Access Journals (Sweden)

    Olivia Pucci

    Full Text Available Because the skin is an oxygen sensor in amphibians and mice, we thought to confirm this function also in humans. The human upright posture, however, introduces additional functional demands for the maintenance of oxygen homeostasis in which cerebral blood flow and autonomic nervous system (ANS function may also be involved. We examined nine males and three females. While subjects were breathing ambient air, at sea level, we changed gases in a plastic body-bag during two conditions of the experiment such as to induce skin hypoxia (with pure nitrogen or skin normoxia (with air. The subjects performed a test of hypoxic ventilatory drive during each condition of the experiment. We found no differences in the hypoxic ventilatory drive tests. However, ANS function and cerebral blood flow velocities were modulated by skin hypoxia and the effect was significantly greater on the left than right middle cerebral arteries. We conclude that skin hypoxia modulates ANS function and cerebral blood flow velocities and this might impact life styles and tolerance to ambient hypoxia at altitude. Thus the skin in normal humans, in addition to its numerous other functions, is also an oxygen sensor.

  5. A preliminary investigation of the impact of oily skin on quality of life and concordance of self-perceived skin oiliness and skin surface lipids (sebum).

    Science.gov (United States)

    Wu, Y; Niu, Y; Zhong, S; Liu, H; Zhen, Y; Saint-Leger, D; Verschoore, M

    2013-10-01

    This preliminary study investigated both the impact of oily skin on quality of life (QoL) and the agreement between subjective oily skin self-assessment and objective skin surface sebum measurement in young to middle-aged Chinese women in Beijing. A 18-item Chinese version of the Oily Skin Self-Image Questionnaire (OSSIQ) was used to assess the impact of oily skin on QoL in 300 healthy female subjects (age groups: 20-25; 26-30; 31-35,). The subjects were divided equally into the oily skin group and the non-oily skin group based on their self-perception of skin oiliness. The level of skin surface lipids (SSL) was measured on the middle of the forehead, and both cheeks using the Sebumeter(®). In order to assess the agreement between self-perceived skin oiliness and measured SSL, we tentatively used the SSL median value as a dividing point to regroup all subjects. The results indicate that the Chinese version of the OSSIQ distinguished the oily skin group from the non-oily skin group. Subjects in the oily skin group had significant higher emotional status score and behavior score when compared with subjects in the non-oily skin group. Subjects in the oily skin group had higher SSL when compared with subjects in the non-oily skin group, especially in younger age groups. The agreement between self-perceived skin oiliness and measured SSL was moderately strong in younger age groups, and declined with age. These results strongly suggest that having oily skin can cause a significant negative impact on QoL among Chinese women. The Chinese version of the OSSIQ is a reliable and valid tool for assessing the impact of oily skin on QoL. The accuracy of oily skin self-assessment declines with age. © 2013 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  6. Mobile phone radiation might alter protein expression in human skin

    Directory of Open Access Journals (Sweden)

    Nylund Reetta

    2008-02-01

    Full Text Available Abstract Background Earlier we have shown that the mobile phone radiation (radiofrequency modulated electromagnetic fields; RF-EMF alters protein expression in human endothelial cell line. This does not mean that similar response will take place in human body exposed to this radiation. Therefore, in this pilot human volunteer study, using proteomics approach, we have examined whether a local exposure of human skin to RF-EMF will cause changes in protein expression in living people. Results Small area of forearm's skin in 10 female volunteers was exposed to RF-EMF (specific absorption rate SAR = 1.3 W/kg and punch biopsies were collected from exposed and non-exposed areas of skin. Proteins extracted from biopsies were separated using 2-DE and protein expression changes were analyzed using PDQuest software. Analysis has identified 8 proteins that were statistically significantly affected (Anova and Wilcoxon tests. Two of the proteins were present in all 10 volunteers. This suggests that protein expression in human skin might be affected by the exposure to RF-EMF. The number of affected proteins was similar to the number of affected proteins observed in our earlier in vitro studies. Conclusion This is the first study showing that molecular level changes might take place in human volunteers in response to exposure to RF-EMF. Our study confirms that proteomics screening approach can identify protein targets of RF-EMF in human volunteers.

  7. Composition of human skin microbiota affects attractiveness to malaria mosquitoes.

    Directory of Open Access Journals (Sweden)

    Niels O Verhulst

    Full Text Available The African malaria mosquito Anopheles gambiae sensu stricto continues to play an important role in malaria transmission, which is aggravated by its high degree of anthropophily, making it among the foremost vectors of this disease. In the current study we set out to unravel the strong association between this mosquito species and human beings, as it is determined by odorant cues derived from the human skin. Microbial communities on the skin play key roles in the production of human body odour. We demonstrate that the composition of the skin microbiota affects the degree of attractiveness of human beings to this mosquito species. Bacterial plate counts and 16S rRNA sequencing revealed that individuals that are highly attractive to An. gambiae s.s. have a significantly higher abundance, but lower diversity of bacteria on their skin than individuals that are poorly attractive. Bacterial genera that are correlated with the relative degree of attractiveness to mosquitoes were identified. The discovery of the connection between skin microbial populations and attractiveness to mosquitoes may lead to the development of new mosquito attractants and personalized methods for protection against vectors of malaria and other infectious diseases.

  8. Biogeography and individuality shape function in the human skin metagenome.

    Science.gov (United States)

    Oh, Julia; Byrd, Allyson L; Deming, Clay; Conlan, Sean; Kong, Heidi H; Segre, Julia A

    2014-10-02

    The varied topography of human skin offers a unique opportunity to study how the body's microenvironments influence the functional and taxonomic composition of microbial communities. Phylogenetic marker gene-based studies have identified many bacteria and fungi that colonize distinct skin niches. Here metagenomic analyses of diverse body sites in healthy humans demonstrate that local biogeography and strong individuality define the skin microbiome. We developed a relational analysis of bacterial, fungal and viral communities, which showed not only site specificity but also individual signatures. We further identified strain-level variation of dominant species as heterogeneous and multiphyletic. Reference-free analyses captured the uncharacterized metagenome through the development of a multi-kingdom gene catalogue, which was used to uncover genetic signatures of species lacking reference genomes. This work is foundational for human disease studies investigating inter-kingdom interactions, metabolic changes and strain tracking, and defines the dual influence of biogeography and individuality on microbial composition and function.

  9. Effects of sunscreen on human skin's ultraviolet radiation tolerance.

    Science.gov (United States)

    Yuan, Chao; Wang, Xue-min; Tan, Yi-mei; Yang, Li-jie; Lin, Yin-fen; Wu, Pei-lan

    2010-12-01

    To observe the alteration ultraviolet radiation (UVR) of skin's tolerance after its exposure to the small dose of UVR under the protection of sunscreen. Eleven subjects who applied sunscreen were exposed to 0.75 dose minimal persistent pigment darkening (MPPD) and minimal erythema dose (MED) by the Phototherapy Unit for 4 weeks. Each week their MPPDs and MEDs were measured by solar simulator. Meanwhile, SPECTCOLOMETER® and VISIOSCAN VC98® were used to detect the test areas and control areas. The values of MPPD and MED increased significantly after the exposure to UVR. But there were no visible changes on the surface of skin's texture. With the protection of sunscreen, the UVR tolerance of skin was greatly increased after the skin's exposure to the small dose UV. © 2010 Wiley Periodicals, Inc.

  10. Method of making self-cleaning skin-like prosthetic polymer surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, John T.; Ivanov, Ilia N.; Shibata, Jason

    2017-06-06

    An external covering and method of making an external covering for hiding the internal endoskeleton of a mechanical (e.g., prosthetic) device that exhibits skin-like qualities is provided. The external covering generally comprises an internal bulk layer in contact with the endoskeleton of the prosthetic device and an external skin layer disposed about the internal bulk layer. The external skin layer is comprised of a polymer composite with carbon nanotubes embedded therein. The outer surface of the skin layer has multiple cone-shaped projections that provide the external skin layer with superhydrophobicity. The carbon nanotubes are preferably vertically aligned between the inner surface and outer surface of the external skin layer in order to provide the skin layer with the ability to transmit heat. Superhydrophobic powders may optionally be used as part of the polymer composite or applied as a coating to the surface of the skin layer to enhance superhydrophobicity.

  11. In vivo study of human skin using pulsed terahertz radiation

    Energy Technology Data Exchange (ETDEWEB)

    Pickwell, E [Semiconductor Physics Group, Cavendish Laboratory, Cambridge University, Madingley Road, Cambridge CB3 0HE (United Kingdom); Cole, B E [TeraView Ltd, Unit 302/4 Cambridge Science Park, Cambridge CB4 0WG (United Kingdom); Fitzgerald, A J [TeraView Ltd, Unit 302/4 Cambridge Science Park, Cambridge CB4 0WG (United Kingdom); Pepper, M [Semiconductor Physics Group, Cavendish Laboratory, Cambridge University, Madingley Road, Cambridge CB3 0HE (United Kingdom); Wallace, V P [TeraView Ltd, Unit 302/4 Cambridge Science Park, Cambridge CB4 0WG (United Kingdom)

    2004-05-07

    Studies in terahertz (THz) imaging have revealed a significant difference between skin cancer (basal cell carcinoma) and healthy tissue. Since water has strong absorptions at THz frequencies and tumours tend to have different water content from normal tissue, a likely contrast mechanism is variation in water content. Thus, we have previously devised a finite difference time-domain (FDTD) model which is able to closely simulate the interaction of THz radiation with water. In this work we investigate the interaction of THz radiation with normal human skin on the forearm and palm of the hand in vivo. We conduct the first ever systematic in vivo study of the response of THz radiation to normal skin. We take in vivo reflection measurements of normal skin on the forearm and palm of the hand of 20 volunteers. We compare individual examples of THz responses with the mean response for the areas of skin under investigation. Using the in vivo data, we demonstrate that the FDTD model can be applied to biological tissue. In particular, we successfully simulate the interaction of THz radiation with the volar forearm. Understanding the interaction of THz radiation with normal skin will form a step towards developing improved imaging algorithms for diagnostic detection of skin cancer and other tissue disorders using THz radiation.

  12. Permeation of platinum and rhodium nanoparticles through intact and damaged human skin

    Energy Technology Data Exchange (ETDEWEB)

    Mauro, Marcella [University of Trieste, Clinical Unit of Occupational Medicine, Department of Medical Sciences (Italy); Crosera, Matteo; Bianco, Carlotta; Adami, Gianpiero; Montini, Tiziano; Fornasiero, Paolo [University of Trieste, Department of Chemical and Pharmaceutical Sciences (Italy); Jaganjac, Morana [Rudjer Boskovic Institute, Laboratory for Oxidative Stress, Department of Molecular Medicine (Croatia); Bovenzi, Massimo; Filon, Francesca Larese, E-mail: larese@units.it [University of Trieste, Clinical Unit of Occupational Medicine, Department of Medical Sciences (Italy)

    2015-06-15

    The aim of the study was to evaluate percutaneous penetration of platinum and rhodium nanoparticles (PtNPs: 5.8 ± 0.9 nm, RhNPs: 5.3 ± 1.9 nm) through human skin. Salts compounds of these metals are sensitizers and some also carcinogenic agents. In vitro permeation experiments were performed using Franz diffusion cells with intact and damaged skin. PtNPs and RhNPs, stabilized with polyvinylpyrrolidone, were synthesized by reduction of Na{sub 2}PtC{sub l6} and RhCl{sub 3}·3H{sub 2}O respectively. Suspensions with a concentration of 2.0 g/L of PtNPs and RhNPs were dispersed separately in synthetic sweat at pH 4.5 and applied as donor phases to the outer surface of the skin for 24 h. Measurements of the content of the metals in the receiving solution and in the skin were performed subsequently. Rhodium skin permeation was demonstrated through damaged skin, with a permeation flux of 0.04 ± 0.04 μg cm{sup −2} h{sup −1} and a lag time of 7.9 ± 1.1 h, while no traces of platinum were found in receiving solutions. Platinum and rhodium skin-analysis showed significantly higher concentrations of the metals in damaged skin. Rh and Pt applied as NPs can penetrate the skin barrier and Rh can be found in receiving solutions. These experiments pointed out the need for skin contamination prevention, since even a minor injury to the skin barrier can significantly increase penetration.

  13. Gene delivery into human skin in vitro using biphasic lipid vesicles.

    Science.gov (United States)

    Foldvari, Marianna; Kumar, Praveen; King, Martin; Batta, Ravinder; Michel, Deborah; Badea, Ildiko; Wloch, Mary

    2006-01-01

    Topical gene delivery to the skin shows great potential for painless, non-invasive administration of novel vaccines and therapeutic agents. The challenge is to develop a pharmaceutically acceptable system that can deliver suitable amounts of plasmid DNA to produce the desired level of response. The purpose of this study was to quantitatively assess DNA delivery by a novel lipid-based biphasic delivery system into the viable layers of excised human skin. Biphasic lipid vesicle formulations, incorporating plasmid DNA were evaluated in vitro in flow-through diffusion cells. Fifty mg DNA formulation containing 10 microg DNA was applied to full-thickness human breast skin for 24 hours. Residual formulation was removed and the skin was washed with PBS, then tape-stripped, followed by DNase treatment to remove surface bound DNA. Skin samples were homogenised and digested overnight with Proteinase K. The resulting supernatant was used as a template for quantitative PCR. Three formulations yielded a significant degree of dermal absorption compared to the controls. Formulation 26-3-2-DNA indicated that approximately 1x10(9) copies of plasmid were absorbed per cm2 skin. Other formulations resulted in 5x10(6) copies/cm2 skin (17C3-1-DNA) and 5x10(8) copies/cm2 skin (26-3-1-DNA). Biphasic vesicles delivered significant quantities of plasmid DNA into the 'viable' layers of human skin in vitro. The successful delivery of this large (approximately 4,400 kDa) charged molecule through intact stratum corneum represents a major advance in transdermal macromolecule delivery.

  14. Influence of probe pressure on diffuse reflectance spectra of human skin measured in vivo.

    Science.gov (United States)

    Popov, Alexey P; Bykov, Alexander V; Meglinski, Igor V

    2017-11-01

    Mechanical pressure superficially applied on the human skin surface by a fiber-optic probe influences the spatial distribution of blood within the cutaneous tissues. Upon gradual load of weight on the probe, a stepwise increase in the skin reflectance spectra is observed. The decrease in the load follows the similar inverse staircase-like tendency. The observed stepwise reflectance spectra changes are due to, respectively, sequential extrusion of blood from the topical cutaneous vascular beds and their filling afterward. The obtained results are confirmed by Monte Carlo modeling. This implies that pressure-induced influence during the human skin diffuse reflectance spectra measurements in vivo should be taken into consideration, in particular, in the rapidly developing area of wearable gadgets for real-time monitoring of various human body parameters. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  15. OCT monitoring of cosmetic creams in human skin in vivo

    Science.gov (United States)

    Han, Seung Hee; Yoon, Chang Han; Conroy, Leigh; Vitkin, I. Alex

    2012-02-01

    Optical coherence tomography (OCT) is a tool currently used for noninvasive diagnosis of human disease as well as for monitoring treatment during or after therapy. In this study, OCT was used to examine penetration and accumulation of cosmetic creams on human hand skin. The samples varied in collagen content with one formulation containing soluble collagen as its primary active ingredient. Collagen is a major connective tissue protein that is essential in maintaining health vitality and strength of many organs. The penetration and localization of collagen in cosmetic creams is thought to be the main determinant of the efficacy of new collagen synthesis. Detection and quantification of collagen in cosmetic creams applied to skin may thus help predict the eventual efficacy of the product in skin collagen regeneration. We hypothesize that the topically applied collagen may be detectable by OCT through its modulation of skin scattering properties. To test this hypothesis, we used a FDML swept-source optical coherence tomography (SS-OCT) system. A particular location on the skin of two male adult volunteers was used to investigate 4 different cosmetic creams. The duration of OCT monitoring of cosmetic penetration into skin ranged from 5 minutes to 2 hours following topical application. The results showed that OCT can discriminate between a cream with collagen and other collagen-free formulations. Thus it seems feasible that OCT intensity can monitor the in vivo effects of topical application of collagen contained in cosmetic formulations.

  16. An immunohistological study of anhydrous topical ascorbic acid compositions on ex vivo human skin.

    Science.gov (United States)

    Heber, Geoffrey K; Markovic, Boban; Hayes, Amanda

    2006-06-01

    Ascorbic acid has numerous essential and beneficial functions in normal and photoaged skin. Ionisation of ascorbic acid in aqueous topical formulations leads to oxidative degradation. Ascorbic acid in an anhydrous vehicle would inherently have greater stability. The objective of this study was to observe the effects of two anhydrous formulations containing microfine particles of ascorbic acid on neocollagenesis and cytokeratin production in ex vivo human skin. Vitamin C preparations were applied topically onto the surface of freshly excised human abdominal skin. Following an exposure time of 48 h with appropriate controls, skin discs were cut into sections, placed on slides and assessed using immunohistochemical (antibodies: collagen type I, III, cytokeratin) staining. Analysis was performed using microscopy and descriptive rating. Both formulations resulted in increased production of collagen types I and III and cytokeratin. The application of anhydrous formulations containing microfine particles of ascorbic acid to ex vivo human skin in this study resulted in neocollagenesis and increased production of cytokeratin. This approach appears to enable biological effects of ascorbic acid in the skin using a vehicle which would provide it greater stability than an aqueous vehicle.

  17. Demodex folliculorum: its association with oily skin surface rather than rosacea lesions.

    Science.gov (United States)

    Porta Guardia, Carlos A

    2015-01-01

    Despite the predilection of Demodex folliculorum (DF) for human sebum, observational studies addressing a relationship between this agent and rosacea paid no attention to the effect of a potentially acting confounder, the oily nature of the skin. To analyze whether a relationship exists between the presence of the mite in rosacea and oily cutis. An observational study on 63 rosacea cases and 61 healthy controls, both discriminated according to their predominance of oily or dry cutis, was carried out to investigate demodectic density by the skin surface biopsy. While comparisons on the density of DF revealed no differences between patients and controls (Mann-Whitney U-test, P = 0.35), persons with an oily cutis had increased amounts of this mite on the skin surface (Mann-Whitney U-test, P rosacea or not. The association between DF and oily skin rather than rosacea lesions gives no support for this agent being implied in disease pathogenesis. © 2014 The International Society of Dermatology.

  18. Human skin color clustering for face detection

    OpenAIRE

    Kovač, Jure; Peer, Peter; Solina, Franc

    2003-01-01

    Computer vision is one out of many areas that wants to understand the process of human functionality and copy that process with intention to complement human life with intelligent machines. For better human–computer interaction it is necessary for the machine to see people. This can be achieved by employing face detection algorithms, like the one used in the installation “15 Seconds of Fame”. Mentioned installation unites the areas of modern art and technology. Its algorithm...

  19. Human skin colour clustering for face detection

    OpenAIRE

    Solina, Franc; Peer, Peter; Kovač, Jure

    2015-01-01

    Computer vision is one out of many areas that wants to understand the process of human functionality and copy that process with intention to complement human life with intelligent machines. For better human–computer interaction it is necessary for the machine to see people. This can be achieved by employing face detection algorithms, like the one used in the installation “15 Seconds of Fame”. Mentioned installation unites the areas of modern art and technology. Its algorithm...

  20. An in vitro model for detecting skin irritants: methyl green-pyronine staining of human skin explant cultures

    NARCIS (Netherlands)

    Jacobs, J. J. L.; Lehé, C.; Cammans, K. D. A.; Das, P. K.; Elliott, G. R.

    2002-01-01

    We evaluated the potential of human organotypic skin explant cultures (hOSECs) for screening skin irritants. Test chemicals were applied to the epidermis of the skin explants which were incubated for 4, 24 or 48 h in tissue culture medium. A decrease in epidermal RNA staining, visualised in frozen

  1. Surface Lipids as Multifunctional Mediators of Skin Responses to Environmental Stimuli

    Directory of Open Access Journals (Sweden)

    Chiara De Luca

    2010-01-01

    Full Text Available Skin surface lipid (SSL film is a mixture of sebum and keratinocyte membrane lipids, protecting skin from environment. Its composition is unique for the high percentage of long chain fatty acids, and of the polyterpenoid squalene, absent in other human tissues, and in non-human Primates sebum. Here, the still incomplete body of information on SSL as mediators of external chemical, physical, and microbial signals and stressors is revised, focusing on the central event of the continuous oxidative modification induced by the metabolic activity of residential and pathological microbial flora, natural or iatrogenic UV irradiation, exposure to chemicals and cosmetics. Once alpha-tocopherol and ubiquinol-10 antioxidant defences of SSL are overcome, oxidation of squalene and cholesterol gives rise to reactive by-products penetrating deeper into skin layers, to mediate local defensive inflammatory, photo-protective, immune reactions or, at higher concentrations, inducing local but also systemic immune depression, ultimately implicating skin cancerogenesis. Qualitative modifications of SSL represent a pathogenetic sign of diagnostic value in dermatological disorders involving altered sebum production, like pytiriasis versicolor, acne, atopic or seborrheic dermatitis, as well as photo-aging. Achievements of nutriceutical interventions aimed at restoring normal SSL composition and homeostasis are discussed, as feasible therapeutic goals and major means of photo-protection.

  2. Friction, adhesion and durability and influence of humidity on adhesion and surface charging of skin and various skin creams using atomic force microscopy.

    Science.gov (United States)

    Tang, W; Bhushan, B; Ge, S

    2010-08-01

    Skin cream is commonly used to improve skin health and create a smooth, soft and moist perception by altering the surface roughness, friction, adhesion, elasticity and surface charging of skin surface. In this study, we present the first systematic study on friction, adhesion, durability and influence of humidity on adhesion and surface charging of skin and various skin creams using atomic force microscopy. Skin is subjected to various daily activities with time, and the durability is closely tied to product compositions. Durability of various skin creams was studied by repeated cycling tests. In order to better understand the frictional behaviour, the dynamic viscosities of various skin creams were measured. Skin cream thinly coats the skin surface and can cause drastic changes in the mechanical properties. In addition to mechanical properties, adhesive force is one of the important factors in determining the tactile perception of skin cream and is directly affected by the film thickness. Because the environmental dependence of skin and skin cream is of importance, the influence of humidity on adhesive force, film thickness and Young's modulus mapping were measured using force distance technique. The health and feel of skin are significantly affected by its surface charging, the surface potential of skin and various cream-treated skins was measured using the Kelvin probe method.

  3. Hydrogen sulphide and phosphine interactions with human skin in vitro.

    Science.gov (United States)

    Gaskin, Sharyn; Heath, Linda; Pisaniello, Dino; Evans, Richard; Edwards, John W; Logan, Michael; Baxter, Christina

    2017-04-01

    Accidental or intentional releases of toxic gases can have significant public health consequences and emergency resource demands. Management of exposed individuals during hazardous material incidents should be risk and evidence based, but there are knowledge gaps in relation to dermal absorption of gases and management advice for potentially exposed individuals. Using a modified Organization for Economic Co-operation and Development (OECD) in vitro toxicology protocol with human donor skin, this article reports on two common and odorous chemicals, hydrogen sulphide and phosphine. Results show that undamaged human skin provides a good barrier to hydrogen sulphide (up to 800 ppm) and phosphine (up to 1000 ppm) penetration for up to 30 min exposures, with little variability in the presence of clothing or in elevated temperature and humidity conditions. A practical guideline template for skin decontamination has been developed, and implications of the research for first responders are outlined.

  4. Technical note: comparing von Luschan skin color tiles and modern spectrophotometry for measuring human skin pigmentation.

    Science.gov (United States)

    Swiatoniowski, Anna K; Quillen, Ellen E; Shriver, Mark D; Jablonski, Nina G

    2013-06-01

    Prior to the introduction of reflectance spectrophotometry into anthropological field research during the 1950s, human skin color was most commonly classified by visual skin color matching using the von Luschan tiles, a set of 36 standardized, opaque glass tiles arranged in a chromatic scale. Our goal was to establish a conversion formula between the tile-based color matching method and modern reflectance spectrophotometry to make historical and contemporary data comparable. Skin pigmentation measurements were taken on the forehead, inner upper arms, and backs of the hands using both the tiles and a spectrophotometer on 246 participants showing a broad range of skin pigmentation. From these data, a second-order polynomial conversion formula was derived by jackknife analysis to estimate melanin index (M-index) based on tile values. This conversion formula provides a means for comparing modern data to von Luschan tile measurements recorded in historical reports. This is particularly important for populations now extinct, extirpated, or admixed for which tile-based measures of skin pigmentation are the only data available. Copyright © 2013 Wiley Periodicals, Inc.

  5. Climate change, ozone depletion and the impact on ultraviolet exposure of human skin.

    Science.gov (United States)

    Diffey, Brian

    2004-01-07

    For 30 years there has been concern that anthropogenic damage to the Earth's stratospheric ozone layer will lead to an increase of solar ultraviolet (UV) radiation reaching the Earth's surface, with a consequent adverse impact on human health, especially to the skin. More recently, there has been an increased awareness of the interactions between ozone depletion and climate change (global warming), which could also impact on human exposure to terrestrial UV. The most serious effect of changing UV exposure of human skin is the potential rise in incidence of skin cancers. Risk estimates of this disease associated with ozone depletion suggest that an additional peak incidence of 5000 cases of skin cancer per year in the UK would occur around the mid-part of this century. Climate change, which is predicted to lead to an increased frequency of extreme temperature events and high summer temperatures, will become more frequent in the UK. This could impact on human UV exposure by encouraging people to spend more time in the sun. Whilst future social trends remain uncertain, it is likely that over this century behaviour associated with climate change, rather than ozone depletion, will be the largest determinant of sun exposure, and consequent impact on skin cancer, of the UK population.

  6. Neurotrophin-3 is increased in skin in human diabetic neuropathy

    Science.gov (United States)

    Kennedy, A; Wellmer, A; Facer, P; Saldanha, G; Kopelman, P; Lindsay, R; Anand, P

    1998-01-01

    Neurotrophin-3 (NT-3), a member of the neurotrophin family, has been shown to be necessary for the development of muscle spindle and Merkel cell afferent nerve fibres in animal models.The presence of NT-3 in the suprabasal epidermis, where many unmyelinated sensory fibres terminate, has been shown for the first time. As these fibres are affected in early diabetic neuropathy and a clinical trial of recombinant human NT-3 in diabetic neuropathy is in progress, the concentrations of endogenous NT-3 in skin of 24 patients at different stages of diabetic polyneuropathy have been investigated. NT-3 concentrations, measured with a specific immunoassay, were significantly higher in affected skin biopsies from patients with diabetic neuropathy than matched control skin (diabetic skin 6.32(1.18) pg/mg v control skin 1.28 (0.05) (mean (SEM)); p<0.004, Mann-Whitney U test), particularly in the later stages. The optical density of NT-3-immunostaining was also significantly greater in the epidermis in diabetic patients (diabetic epidermis 0.30(0.06) v controls 0.24 (0.01); p<0.02). No correlation was found between individual quantitative sensory tests and the increase of NT-3 concentration. The increase of NT-3 seems to reflect the degree of skin denervation in diabetic neuropathy, and may represent a compensatory mechanism. The concentrations of NT-3 in other peripheral targets deserve study in diabetic neuropathy.

 PMID:9728960

  7. The Response of the Ocean Thermal Skin Layer to Air-Sea Surface Heat Fluxes

    Science.gov (United States)

    Wong, Elizabeth Wing-See

    There is much evidence that the ocean is heating as a result of an increase in concentrations of greenhouse gases (GHGs) in the atmosphere from human activities. GHGs absorb infrared radiation and re-emit infrared radiation back to the ocean's surface which is subsequently absorbed. However, the incoming infrared radiation is absorbed within the top micrometers of the ocean's surface which is where the thermal skin layer exists. Thus the incident infrared radiation does not directly heat the upper few meters of the ocean. We are therefore motivated to investigate the physical mechanism between the absorption of infrared radiation and its effect on heat transfer at the air-sea boundary. The hypothesis is that since heat lost through the air-sea interface is controlled by the thermal skin layer, which is directly influenced by the absorption and emission of infrared radiation, the heat flow through the thermal skin layer adjusts to maintain the surface heat loss, assuming the surface heat loss does not vary, and thus modulates the upper ocean heat content. This hypothesis is investigated through utilizing clouds to represent an increase in incoming longwave radiation and analyzing retrieved thermal skin layer vertical temperature profiles from a shipboard infrared spectrometer from two research cruises. The data are limited to night-time, no precipitation and low winds of less than 2 m/s to remove effects of solar radiation, wind-driven shear and possibilities of thermal skin layer disruption. The results show independence of the turbulent fluxes and emitted radiation on the incident radiative fluxes which rules out the immediate release of heat from the absorption of the cloud infrared irradiance back into the atmosphere through processes such as evaporation and increase infrared emission. Furthermore, independence was confirmed between the incoming and outgoing radiative flux which implies the heat sink for upward flowing heat at the air-sea interface is more

  8. Enhancement of Human Cheek Skin Texture by Acacia Nilotica Bark ...

    African Journals Online (AJOL)

    ... of a topical application of a cream formulation containing extract of Acacia nilotica bark extract on human cheek skin texture. Methods: A cream containing 3 % concentrated extract of Acacia nilotica bark was developed by entrapping the extract in the internal aqueous phase of the cream having strong antioxidant activity.

  9. Human skin Langerhans cells are targets of dengue virus infection

    NARCIS (Netherlands)

    Wu, SJL; Grouard-Vogel, G; Mascola, [No Value; Brachtel, E; Putvatana, R; Louder, MK; Filgueira, L; Marovich, MA; Wong, HK; Blauvelt, A; Murphy, GS; Robb, ML; Innes, BL; Birx, DL; Hayes, CG; Frankel, SS

    Dengue virus (DV), an arthropod-borne flavivirus, causes a febrile illness for which there is no antiviral treatment and no vaccine(1,2). Macrophages are important in dengue pathogenesis; however, the initial target cell for DV infection remains unknown. As DV is introduced into human skin by

  10. Sarcoptes scabiei mites modulate gene expression in human skin equivalents.

    Directory of Open Access Journals (Sweden)

    Marjorie S Morgan

    Full Text Available The ectoparasitic mite, Sarcoptes scabiei that burrows in the epidermis of mammalian skin has a long co-evolution with its hosts. Phenotypic studies show that the mites have the ability to modulate cytokine secretion and expression of cell adhesion molecules in cells of the skin and other cells of the innate and adaptive immune systems that may assist the mites to survive in the skin. The purpose of this study was to identify genes in keratinocytes and fibroblasts in human skin equivalents (HSEs that changed expression in response to the burrowing of live scabies mites. Overall, of the more than 25,800 genes measured, 189 genes were up-regulated >2-fold in response to scabies mite burrowing while 152 genes were down-regulated to the same degree. HSEs differentially expressed large numbers of genes that were related to host protective responses including those involved in immune response, defense response, cytokine activity, taxis, response to other organisms, and cell adhesion. Genes for the expression of interleukin-1α (IL-1α precursor, IL-1β, granulocyte/macrophage-colony stimulating factor (GM-CSF precursor, and G-CSF precursor were up-regulated 2.8- to 7.4-fold, paralleling cytokine secretion profiles. A large number of genes involved in epithelium development and keratinization were also differentially expressed in response to live scabies mites. Thus, these skin cells are directly responding as expected in an inflammatory response to products of the mites and the disruption of the skin's protective barrier caused by burrowing. This suggests that in vivo the interplay among these skin cells and other cell types, including Langerhans cells, dendritic cells, lymphocytes and endothelial cells, is responsible for depressing the host's protective response allowing these mites to survive in the skin.

  11. Tumor angiogenic factor and human skin tumors.

    Science.gov (United States)

    Wolf, J E; Hubler, W R

    1975-03-01

    A transparent acrylic hamster cheek-pouch chamber was used to investigate the elaboration of a tumor angiogenic factor (TAF) by human cutaneous neoplasms; direct tumor implantations, transfilter diffusion, and soluble tumor extracts were used in the study. A diffusible and filterable TAF was extracted from cutaneous tumors and produced distinctive patterns of sequential vasodilatation, tortuosity, and neovascular proliferation in the cheek-pouch membrane. Malignant human neoplasms (eg, melanoma, basal cell epithelioma, squamous cell carcinoma, lymphoma) produced striking neovascularization; vascular tumors (eg, Kaposi sarcoma, pyogenic granuloma, vascular histiocytoma) stimulated dramatic hyperemia and ectasia. Angiogenesis was conspicuously absent after implantation of control materials and nevoid or normal cutaneous components (with the exception of epidermis). Tumor angiogenic factor appears to induce direct stimulation of endothelial cell mitosis and may be essential for survival of nutritionally ravenous neoplastic tissues. The interference with TAF has therapeutic implications.

  12. Raman measurement of carotenoid composition in human skin

    Science.gov (United States)

    Ermakov, Igor V.; Ermakova, Maia R.; Gellermann, Werner

    2004-07-01

    The carotenoids lycopene and beta-carotene are powerful antioxidants in skin and are thought to act as scavengers for free radicals and singlet oxygen. The role of carotenoid species in skin health is of strong current interest. We demonstrate the possibility to use Resonance Raman spectroscopy for fast, non-invasive, highly specific, and quantitative detection of beta-carotene and lycopene in human skin. Analyzing Raman signals originating from the carbon-carbon double bond stretch vibrations of the carotenoid molecules under blue and green laser excitation, we were able to characterize quantitatively the relative concentrations of each carotenoid species in-vivo. In the selective detection, we take advantage of different Raman cross-section spectral profiles for beta-carotene and lycopene molecules, and obtain a quantitative assessment of individual long-chain carotenoid species in the skin rather than their cumulative levels. Preliminary dual-wavelength Raman measurements reveal significant differences in the carotenoid composition of different subjects. The technique holds promise for rapid screening of carotenoid compositions in human skin in large populations and may be suitable in clinical studies for assessing the risk for cutaneous diseases.

  13. In vivo multimodality video microscopy of human skin in the vertical plane (Conference Presentation)

    Science.gov (United States)

    Wu, Zhenguo; Tian, Yunxian; Zhao, Jianhua; Lui, Harvey; McLean, David I.; Zeng, Haishan

    2016-02-01

    Reflectance confocal microscopy (RCM) and multiphoton microscopy (MPM) are non-invasive methods of acquiring morphological images of the skin in vivo. Most research in this area focuses on instruments that are configured for two-dimensional imaging in a horizontal plane parallel to the skin surface. In contrast, conventional histopathologic evaluation of the skin is based on vertical tissue sections that show microscopic features and their interrelationships according to their depth within the skin. The ability to similarly depict the skin in the vertical plane during in vivo microscopic imaging poses several significant challenges with respect to imaging speed, resolution and extractable information. Aiming to address above challenges, we developed a laser scanning multimodal microscopy system which combines RCM and MPM, and has the ability to do fast xz scanning to achieve high resolution vertical "optical sectioning" of in vivo human skin at video rates. RCM and MPM images are obtained simultaneously and co-registered thereby providing complementary morphological information. To validate the performance of this system vertical section RCM and MPM microscopic images of normal human skin in vivo were obtained at half video rates (15 frames/s). Using our system it is possible to discern the following structures: all layers of the epidermis including the stratum lucidum, the dermal-epidermal junction, and the papillary dermis. Blood flow is also visible as evidenced by blood cell movement within vessels. The effective imaging depth is about 200 micrometers. This system provides a means of interrogating human skin noninvasively at an orientation analogous to conventional histological sectioning.

  14. Conformal, wearable, thin microwave antenna for sub-skin and skin surface monitoring

    Science.gov (United States)

    Converse, Mark C.; Chang, John T.; Duoss, Eric B.

    2017-05-16

    A wearable antenna is operably positioned on a wearer's skin and is operably connected the wearer's tissue. A first antenna matched to the wearer's tissue is operably positioned on the wearer's skin. A second antenna matched to the air is operably positioned on the wearer's skin. Transmission lines connect the first antenna and the second antenna.

  15. Microsphaeropsis olivacea as an etiological agent of human skin infection.

    Science.gov (United States)

    Guarro, J; Mayayo, E; Tapiol, J; Aguilar, C; Cano, J

    1999-04-01

    Microsphaeropsis olivacea is reported as the agent of a case of human skin infection in an otherwise healthy woman. This fungus has not been reported previously as causing disease in humans. It was identified on the basis of its production of pycnidia and conidial structures typical of the Coelomycetes, and by its light brown, ellipsoid to cylindrical and thick walled conidia. The in vitro inhibitory activity of amphotericin B, fluconazole, flucytosine, itraconazole, ketoconazole and miconazole was determined.

  16. Detection of advanced glycation end products (AGEs) on human skin by in vivo confocal Raman spectroscopy

    Science.gov (United States)

    Martin, A. A.; Pereira, L.; Ali, S. M.; Pizzol, C. D.; Tellez, C. A.; Favero, P. P.; Santos, L.; da Silva, V. V.; Praes, C. E. O.

    2016-03-01

    The aging process involves the reduction in the production of the major components of skin tissue. During intrinsic aging and photoaging processes, in dermis of human skin, fibroblasts become senescent and have decreased activity, which produce low levels of collagen. Moreover, there is accumulation of advanced glycation end products (AGEs). AGEs have incidence in the progression of age-related diseases, principally in diabetes mellitus and in Alzheimer's diseases. AGEs causes intracellular damage and/or apoptosis leading to an increase of the free radicals, generating a crosslink with skin proteins and oxidative stress. The aim of this study is to detect AGEs markers on human skin by in vivo Confocal Raman spectroscopy. Spectra were obtained by using a Rivers Diagnostic System, 785 nm laser excitation and a CCD detector from the skin surface down to 120 μm depth. We analyzed the confocal Raman spectra of the skin dermis of 30 women volunteers divided into 3 groups: 10 volunteers with diabetes mellitus type II, 65-80 years old (DEW); 10 young healthy women, 20-33 years old (HYW); and 10 elderly healthy women, 65-80 years old (HEW). Pentosidine and glucosepane were the principally identified AGEs in the hydroxyproline and proline Raman spectral region (1000-800 cm-1), in the 1.260-1.320 cm-1 region assignable to alpha-helical amide III modes, and in the Amide I region. Pentosidine and glucosepane calculated vibrational spectra were performed through Density Functional Theory using the B3LYP functional with 3-21G basis set. Difference between the Raman spectra of diabetic elderly women and healthy young women, and between healthy elderly women and healthy young women were also obtained with the purpose of identifying AGEs Raman bands markers. AGEs peaks and collagen changes have been identified and used to quantify the glycation process in human skin.

  17. Conformal, wearable, thin microwave antenna for sub-skin and skin surface monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Converse, Mark C.; Chang, John T.; Duoss, Eric B.

    2017-05-16

    A wearable antenna is operably positioned on a wearer's skin and is operably connected the wearer's tissue. A first antenna matched to the wearer's tissue is operably positioned on the wearer's skin. A second antenna matched to the air is operably positioned on the wearer's skin. Transmission lines connect the first antenna and the second antenna.

  18. A novel ATX-S10(Na) photodynamic therapy for human skin tumors and benign hyperproliferative skin.

    Science.gov (United States)

    Takahashi, Hidetoshi; Itoh, Yasuhiro; Nakajima, Susumu; Sakata, Isao; Iizuka, Hajime

    2004-10-01

    Photodynamic therapy (PDT) is a promising treatment for various skin tumors and other skin diseases. We investigated the potential therapeutic effects of PDT using ATX-S10(Na) ointment and a diode laser in mouse skin models of experimental skin tumors as well as transplanted human samples of superficial skin tumors and lesional psoriatic skin. ATX-S10(Na) ointment (1% w/v) was introduced into tape-stripped mouse skin, transplanted squamous cell carcinoma (SCC) samples and human skin diseases after topical application, then PDT was performed. ATX-S10(Na) ointment (1% w/v) was introduced effectively into tape-stripped mouse skin and transplanted SCC samples after topical application, but was not detected after 48 h, as assessed by fluorescence microscopy. PDT, using 1% ATX-S10(Na) ointment and diode laser (50 J/cm(2)), was found to decrease epidermal thickness in 12-0-tetradecanoylphorbol-13-acetate (TPA)-treated mouse skin by 6 days. PDT with 1% ATX-S10(Na) ointment and diode laser (150 J/cm(2)) was also effective for transplanted SCC, and tumors were eliminated by 6 weeks. PDT against Bowen disease, basal-cell carcinoma, and psoriasis xenografts onto SCID mice also showed marked suppression of tumor growth and cell proliferation, respectively. Our results indicate that ATX-S10(Na)-PDT is an effective treatment for various skin tumors and psoriasis in experimental mouse models.

  19. Treatment of surfactant-damaged skin in humans with creams of different pH values.

    Science.gov (United States)

    Buraczewska, Izabela; Lodén, Marie

    2005-01-01

    Skin surface has an acidic pH, whereas the body's internal environment maintains a near-neutral pH. The physiological role of the 'acidic mantle' and the function of the pH gradient throughout the stratum corneum remain unexplained. The pH gradient has been suggested to activate enzymes responsible for the maintenance of the skin barrier function and to facilitate the desquamation process in the stratum corneum. The aim of the study was to investigate the influence of pH of a moisturizing cream on barrier recovery in surfactant-damaged human skin. Volunteers had their skin damaged with sodium lauryl sulphate and treated those areas with the cream, adjusted to either pH 4.0 or 7.5. The study did not prove the superiority of a cream of pH 4.0 to a cream of pH 7.5 regarding promotion of skin barrier recovery, since no significant differences (p > 0.05) were found in transepidermal water loss, blood flow and skin capacitance between the treated areas. 2005 S. Karger AG, Basel.

  20. Three-Dimensional In Vitro Skin and Skin Cancer Models Based on Human Fibroblast-Derived Matrix.

    Science.gov (United States)

    Berning, Manuel; Prätzel-Wunder, Silke; Bickenbach, Jackie R; Boukamp, Petra

    2015-09-01

    Three-dimensional in vitro skin and skin cancer models help to dissect epidermal-dermal and tumor-stroma interactions. In the model presented here, normal human dermal fibroblasts isolated from adult skin self-assembled into dermal equivalents with their specific fibroblast-derived matrix (fdmDE) over 4 weeks. The fdmDE represented a complex human extracellular matrix that was stabilized by its own heterogeneous collagen fiber meshwork, largely resembling a human dermal in vivo architecture. Complemented with normal human epidermal keratinocytes, the skin equivalent (fdmSE) thereof favored the establishment of a well-stratified and differentiated epidermis and importantly allowed epidermal regeneration in vitro for at least 24 weeks. Moreover, the fdmDE could be used to study the features of cutaneous skin cancer. Complementing fdmDE with HaCaT cells in different stages of malignancy or tumor-derived cutaneous squamous cell carcinoma cell lines, the resulting skin cancer equivalents (fdmSCEs) recapitulated the respective degree of tumorigenicity. In addition, the fdmSCE invasion phenotypes correlated with their individual degree of tissue organization, disturbance in basement membrane organization, and presence of matrix metalloproteinases. Together, fdmDE-based models are well suited for long-term regeneration of normal human epidermis and, as they recapitulate tumor-specific growth, differentiation, and invasion profiles of cutaneous skin cancer cells, also provide an excellent human in vitro skin cancer model.

  1. The effect of surface treatment on the microstructure of the skin of concrete

    Science.gov (United States)

    Sadowski, Łukasz; Stefaniuk, Damian

    2018-01-01

    The aim of this study is to better understand the heterogeneity and microstructural properties of the skin of concrete. The microstructural evaluation of the skin of concrete was performed using X-ray micro computed tomography (micro-CT). The concrete surface was treated using four methods, due to which different surfaces were obtained, i.e. a raw surface, a surface formed after contact with formwork, a grinded surface and also a shotblasted surface. The results of the pore structure obtained from the micro-CT images were used to assess the influence of selected surface treatment method on the nature of the skin of concrete. It was shown that the thickness and unique nature of the skin of concrete differ for various surface treatment methods.

  2. Proteome Analysis of Human Sebaceous Follicle Infundibula Extracted from Healthy and Acne-Affected Skin

    Science.gov (United States)

    Bek-Thomsen, Malene; Lomholt, Hans B.; Scavenius, Carsten; Enghild, Jan J.; Brüggemann, Holger

    2014-01-01

    Acne vulgaris is a very common disease of the pilosebaceous unit of the human skin. The pathological processes of acne are not fully understood. To gain further insight sebaceous follicular casts were extracted from 18 healthy and 20 acne-affected individuals by cyanoacrylate-gel biopsies and further processed for mass spectrometry analysis, aiming at a proteomic analysis of the sebaceous follicular casts. Human as well as bacterial proteins were identified. Human proteins enriched in acne and normal samples were detected, respectively. Normal follicular casts are enriched in proteins such as prohibitins and peroxiredoxins which are involved in the protection from various stresses, including reactive oxygen species. By contrast, follicular casts extracted from acne-affected skin contained proteins involved in inflammation, wound healing and tissue remodeling. Among the most distinguishing proteins were myeloperoxidase, lactotransferrin, neutrophil elastase inhibitor and surprisingly, vimentin. The most significant biological process among all acne-enriched proteins was ‘response to a bacterium’. Identified bacterial proteins were exclusively from Propionibacterium acnes. The most abundant P. acnes proteins were surface-exposed dermatan sulphate adhesins, CAMP factors, and a so far uncharacterized lipase in follicular casts extracted from normal as well as acne-affected skin. This is a first proteomic study that identified human proteins together with proteins of the skin microbiota in sebaceous follicular casts. PMID:25238151

  3. Extracellular depolymerization of hyaluronic acid in cultured human skin fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, T.; Takagaki, K.; Kubo, K.; Morikawa, A.; Tamura, S.; Endo, M. (Hirosaki Univ. School of Medicine (Japan))

    1990-10-15

    The chain length of ({sup 3}H)hyaluronic acid synthesized by cultivating human skin fibroblasts in the presence of ({sup 3}H)glucosamine was investigated. ({sup 3}H)Hyaluronic acid obtained from the matrix fraction was excluded from a Sepharose CL-2B column irrespective of the incubation period, whereas that from the medium was depolymerized into a constant chain length (Mr = 40,000). The reducing and non-reducing terminals of the depolymerized hyaluronic acid were N-acetylglucosamine and glucuronic acid, respectively. Prolonged incubation produced no oligosaccharides as shown by examination of hyaluronidase digests, suggesting the presence of a novel endo-beta-N-acetylglucosaminidase in cultured human skin fibroblasts.

  4. Skin frictional resistance of plane surfaces in air

    Science.gov (United States)

    Diehl, W S

    1922-01-01

    Given here is the most recent research on skin frictional resistance of plane surfaces in air that was conducted by Dr. Wieselsberger under the direction of Dr. Prandtl of Gottingen University. In all, 16 models were tested. These were divided into four groups, as follows: 1) cloth, in the original condition; 2) cloth, with the nap singed off; 3) cloth, with three coats of dope; and 4) cloth, with six coats of dope. Each group consisted of four models of uniform width, 1 meter, and of lengths of 0.5, 1.0, 1.5, and 2.0 meters. Tests were made on each model at speeds varying from 7.0 to 50 meters per second. The observed total resistance was corrected for the form resistance which was obtained from the pressure distribution on the end of the model. Previous tests had shown that the form resistance due to the rounded front edge used on the models was negligible. The results are expressed in terms of the absolute coefficient of frictionless resistance, C(sub F).

  5. The collagenic structure of human digital skin seen by scanning electron microscopy after Ohtani maceration technique.

    Science.gov (United States)

    Sangiorgi, Simone; Manelli, Alessandro; Protasoni, Marina; Ronga, Mario; Raspanti, Mario

    2005-03-01

    We performed a morphological scanning electron microscope (SEM) study to describe the fine structure and disposition of collagenous tissue in the human toe. After therapeutic amputation of a human right leg, we applied the Othani maceration technique to the skin of three toes surgically explanted from the foot. We distinguished eight cutaneous regions and focused on some specialized collagenous structures differing in the thickness of the skin. The eight areas investigated were: the dorsal skin, the eponychium, the perionychium, the hyponychium, the region under the visible nail, the nail root, the plantar skin and finally the toe tip. Each of these areas is characterized by a distinctive collagenous surface disposition, with some peculiar features mostly related to dermal papillae. At high magnification, we observed the spatial arrangement of the collagen fibers constituting the top of the dermal papillae that represents the attachment site of the proliferative basal layer of the epidermis. We also noted an impressive density of collagen fibers throughout the thickness of the dermal layer, organized in specialized structures and constituting the skeleton of dermal thermoreceptorial corpuscles or sweat glands. A combination of SEM and Ohtani technique disclosed the three-dimensional architecture of the collagenous matrix of tarsal skin under physiologic conditions, giving a detailed description of the most reactive tissue during pathologic processes.

  6. Imaging of human skin lesions with the multispectral dermoscope

    Science.gov (United States)

    Kapsokalyvas, Dimitrios; Bruscino, Nicola; Alfieri, Domenico; de Giorgi, Vincenzo; Cannarozzo, Giovanni; Lotti, Torello; Pavone, Francesco S.

    2010-02-01

    The Dermoscope is a widespread and essential tool for dermatology. It reveals morphologic characteristics and aid the identification and diagnosis of a skin lesion. The diagnosis though is not always unambiguous and still the use of Dermoscopy doesn't obviate the need for histopathological verification. We report on the development of the Multispectral Dermoscope which employs high luminance LEDs with emission at three distinct spectral regions (470 nm, 530 nm, 625 nm). The illumination is polarized and an analyzer is used for the detection. Subsequent image analysis for enhancing the contrast for single scattered photons, hemoglobin absorption and melanin absorption is performed. Features like the surface texture of the skin, scattering structures in the epidermis, blood vessel morphology even in pigmented lesions and melanin localization have been observed in various skin pathologies. The device has been tested on volunteers and the features revealed have proven to be helpful in the diagnosis of skin lesions. Use of the Multispectral Dermoscope could improve the sensitivity and specificity of Dermoscopy.

  7. A micromechanical comparison of human and porcine skin before and after preservation by freezing for medical device development

    OpenAIRE

    Ranamukhaarachchi, S. A.; Lehnert, S.; Ranamukhaarachchi, S. L.; Sprenger, L.; Schneider, T.; Mansoor, I.; Rai, K.; H?feli, U. O.; Stoeber, B.

    2016-01-01

    Collecting human skin samples for medical research, including developing microneedle-based medical devices, is challenging and time-consuming. Researchers rely on human skin substitutes and skin preservation techniques, such as freezing, to overcome the lack of skin availability. Porcine skin is considered the best substitute to human skin, but their mechanical resemblance has not been fully validated. We provide a direct mechanical comparison between human and porcine skin samples using a co...

  8. A Novel Cassia fistula (L.-Based Emulsion Elicits Skin Anti-Aging Benefits in Humans

    Directory of Open Access Journals (Sweden)

    Barkat Ali Khan

    2015-11-01

    Full Text Available Cassia fistula, a flowering plant in the family of Caesalpinaceae (Fabaceae, is used in traditional medicine for several indications. Nevertheless, too little is known about its effects on skin conditions and skin aging. Therefore, in this pioneering study, the extracts of oil-in-water macro-emulsions containing 5% C. fistula (L. crude pods (i.e., phyto-active formulation were optimally developed and compared to the placebo (i.e., emulsions without the crude extract for assessment of their effects on human skin aging. Healthy adult male volunteers (n = 13 with a mean age of 31 ± 5.5 years (range: 24–47 years were enrolled after informed written consent. For 12 consecutive weeks, the subjects were directed to use a patch containing the active emulsion on one of their forearms as well as a patch containing the placebo on their other forearm. Biometrological measurements of skin hydration (SH and transepidermal water loss (TEWL were performed on both sides of their respective cheeks at time 0 (baseline values, 2, 4, 6, 8, 10 and 12th weeks. Surface evaluation of living skin (SELS was taken at time 0 (baseline values or after 1, 2 and 3 months. Topical application of C. fistula extracts showed a significant (p < 0.05 increase in stratum corneum hydration level, a significant enhancement in its water-holding function as well as in its barrier function. Further, significant (p < 0.005 ameliorations of skin aspects were observed (i.e., less roughness, less dryness, less wrinkles. Taken together, our results strongly suggest therapeutic and esthetic potential of C. fistula pod’s extracts to prevent or delay human skin aging.

  9. Comparison of in vivo and ex vivo laser scanning microscopy and multiphoton tomography application for human and porcine skin imaging

    Science.gov (United States)

    Darvin, M. E.; Richter, H.; Zhu, Y. J.; Meinke, M. C.; Knorr, F.; Gonchukov, S. A.; Koenig, K.; Lademann, J.

    2014-07-01

    Two state-of-the-art microscopic optical methods, namely, confocal laser scanning microscopy in the fluorescence and reflectance regimes and multiphoton tomography in the autofluorescence and second harmonic generation regimes, are compared for porcine skin ex vivo and healthy human skin in vivo. All skin layers such as stratum corneum (SC), stratum spinosum (SS), stratum basale (SB), papillary dermis (PD) and reticular dermis (RD) as well as transition zones between these skin layers are measured noninvasively at a high resolution, using the above mentioned microscopic methods. In the case of confocal laser scanning microscopy (CLSM), measurements in the fluorescence regime were performed by using a fluorescent dye whose topical application on the surface is well suited for the investigation of superficial SC and characterisation of the skin barrier function. For investigations of deeply located skin layers, such as SS, SB and PD, the fluorescent dye must be injected into the skin, which markedly limits fluorescence measurements using CLSM. In the case of reflection CLSM measurements, the obtained results can be compared to the results of multiphoton tomography (MPT) for all skin layers excluding RD. CLSM cannot distinguish between dermal collagen and elastin measuring their superposition in the RD. By using MPT, it is possible to analyse the collagen and elastin structures separately, which is important for the investigation of anti-aging processes. The resolution of MPT is superior to CLSM. The advantages and limitations of both methods are discussed and the differences and similarities between human and porcine skin are highlighted.

  10. Comparison of in vivo and ex vivo laser scanning microscopy and multiphoton tomography application for human and porcine skin imaging

    Energy Technology Data Exchange (ETDEWEB)

    Darvin, M E; Richter, H; Zhu, Y J; Meinke, M C; Knorr, F; Lademann, J [Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin (Germany); Gonchukov, S A [National Research Nuclear University ' ' MEPhI' ' (Russian Federation); Koenig, K [JenLab GmbH, Schillerstr. 1, 07745 Jena (Germany)

    2014-07-31

    Two state-of-the-art microscopic optical methods, namely, confocal laser scanning microscopy in the fluorescence and reflectance regimes and multiphoton tomography in the autofluorescence and second harmonic generation regimes, are compared for porcine skin ex vivo and healthy human skin in vivo. All skin layers such as stratum corneum (SC), stratum spinosum (SS), stratum basale (SB), papillary dermis (PD) and reticular dermis (RD) as well as transition zones between these skin layers are measured noninvasively at a high resolution, using the above mentioned microscopic methods. In the case of confocal laser scanning microscopy (CLSM), measurements in the fluorescence regime were performed by using a fluorescent dye whose topical application on the surface is well suited for the investigation of superficial SC and characterisation of the skin barrier function. For investigations of deeply located skin layers, such as SS, SB and PD, the fluorescent dye must be injected into the skin, which markedly limits fluorescence measurements using CLSM. In the case of reflection CLSM measurements, the obtained results can be compared to the results of multiphoton tomography (MPT) for all skin layers excluding RD. CLSM cannot distinguish between dermal collagen and elastin measuring their superposition in the RD. By using MPT, it is possible to analyse the collagen and elastin structures separately, which is important for the investigation of anti-aging processes. The resolution of MPT is superior to CLSM. The advantages and limitations of both methods are discussed and the differences and similarities between human and porcine skin are highlighted. (laser biophotonics)

  11. Effect of Size, Surface Charge, and Hydrophobicity of Poly(amidoamine) Dendrimers on Their Skin Penetration

    Science.gov (United States)

    Yang, Yang; Sunoqrot, Suhair; Stowell, Chelsea; Ji, Jingli; Lee, Chan-Woo; Kim, Jin Woong; Khan, Seema A.; Hong, Seungpyo

    2012-01-01

    The barrier functions of the stratum corneum (SC) and the epidermal layers present a tremendous challenge in achieving effective transdermal delivery of drug molecules. Although a few reports have shown that poly(amidoamine) (PAMAM) dendrimers are effective skin penetration enhancers, little is known regarding the fundamental mechanisms behind the dendrimer-skin interactions. In this paper, we have performed a systematic study to better elucidate how dendrimers interact with skin layers depending on their size and surface groups. Franz diffusion cells and confocal microscopy were employed to observe dendrimer interactions with full-thickness porcine skin samples. We have found that smaller PAMAM dendrimers (generation 2 (G2)) penetrate the skin layers more efficiently than the larger ones (G4). We have also found that G2 PAMAM dendrimers that are surface modified by either acetylation or carboxylation exhibit increased skin permeation and likely diffuse through an extracellular pathway. In contrast, amine-terminated dendrimers show enhanced cell internalization and skin retention but reduced skin permeation. In addition, conjugation of oleic acid (OA) to G2 dendrimers increases their 1-octanol/PBS partition coefficient, resulting in increased skin absorption and retention. Here we report that size, surface charge, and hydrophobicity directly dictate the permeation route and efficiency of dendrimer translocation across the skin layers, providing a design guideline for engineering PAMAM dendrimers as a potential transdermal delivery vector. PMID:22621160

  12. The safety of donor skin preserved with glycerol - Evaluating the Euro Skin Bank preservation procedures of human donor skin against the prEN 12442 standard

    NARCIS (Netherlands)

    Geertsma RE; Wassenaar C; LGM

    2000-01-01

    The procedures for preservation of human donor skin with glycerol, as applied by the Euro Skin Bank (ESB), were evaluated against the prEN 12442 standard: animal tissues and their derivatives used in the manufacture of medical devices. The focus chosen for this review is on risks related to the

  13. In-Vivo Human Skin to Textiles Friction Measurements

    Science.gov (United States)

    Pfarr, Lukas; Zagar, Bernhard

    2017-10-01

    We report on a measurement system to determine highly reliable and accurate friction properties of textiles as needed for example as input to garment simulation software. Our investigations led to a set-up that allows to characterize not just textile to textile but also textile to in-vivo human skin tribological properties and thus to fundamental knowledge about genuine wearer interaction in garments. The method of test conveyed in this paper is measuring concurrently and in a highly time resolved manner the normal force as well as the resulting shear force caused by a friction subject intending to slide out of the static friction regime and into the dynamic regime on a test bench. Deeper analysis of various influences is enabled by extending the simple model following Coulomb's law for rigid body friction to include further essential parameters such as contact force, predominance in the yarn's orientation and also skin hydration. This easy-to-use system enables to measure reliably and reproducibly both static and dynamic friction for a variety of friction partners including human skin with all its variability there might be.

  14. Hyperspectral imaging for detection of cholesterol in human skin

    Science.gov (United States)

    Milanič, Matija; Bjorgan, Asgeir; Larsson, Marcus; Marraccini, Paolo; Strömberg, Tomas; Randeberg, Lise L.

    2015-03-01

    Hypercholesterolemia is characterized by high levels of cholesterol in the blood and is associated with an increased risk of atherosclerosis and coronary heart disease. Early detection of hypercholesterolemia is necessary to prevent onset and progress of cardiovascular disease. Optical imaging techniques might have a potential for early diagnosis and monitoring of hypercholesterolemia. In this study, hyperspectral imaging was investigated for this application. The main aim of the study was to identify spectral and spatial characteristics that can aid identification of hypercholesterolemia in facial skin. The first part of the study involved a numerical simulation of human skin affected by hypercholesterolemia. A literature survey was performed to identify characteristic morphological and physiological parameters. Realistic models were prepared and Monte Carlo simulations were performed to obtain hyperspectral images. Based on the simulations optimal wavelength regions for differentiation between normal and cholesterol rich skin were identified. Minimum Noise Fraction transformation (MNF) was used for analysis. In the second part of the study, the simulations were verified by a clinical study involving volunteers with elevated and normal levels of cholesterol. The faces of the volunteers were scanned by a hyperspectral camera covering the spectral range between 400 nm and 720 nm, and characteristic spectral features of the affected skin were identified. Processing of the images was done after conversion to reflectance and masking of the images. The identified features were compared to the known cholesterol levels of the subjects. The results of this study demonstrate that hyperspectral imaging of facial skin can be a promising, rapid modality for detection of hypercholesterolemia.

  15. In vivo human-skin electrical conduction and pain sensations

    Energy Technology Data Exchange (ETDEWEB)

    Voegelin, M. R. [Florence, Univ. (Italy). Div. di Fisica Medica. Dipt. di Fisiopatologia; Paoli, G.; Zoppi, M. [Florence, Univ. (Italy). Istituto della I Clinica Medica

    1997-06-01

    In vivo human skin is stimulated by direct current the intensity of which ranges from 1 {mu}A to 1 mA. They have detected the voltage/current plot and the temporal trend of potential difference between two electrodes placed in a suitable cutaneous region of stimulation, in a group of healthy subjects. They have elaborated a non-linear functional equivalent model to describe the system behaviour. The electrical stimulation can induce painful sensation, over a critical value of the current intensity, and they believe that this sensation is due to thermal dissipation into the inner layers of the skin. In fact, subjects begin to feel pain when the electric power dissipated in the stimulated region for unit time is within the range of 235-260 mcal/cm{sup 2}{center_dot}s, that corresponds to the thermal threshold required to evoke pain.

  16. Collagen synthesis in human musculoskeletal tissues and skin

    DEFF Research Database (Denmark)

    Babraj, J A; Cuthbertson, D J R; Smith, K

    2005-01-01

    We have developed a direct method for the measurement of human musculoskeletal collagen synthesis on the basis of the incorporation of stable isotope-labeled proline or leucine into protein and have used it to measure the rate of synthesis of collagen in tendon, ligament, muscle, and skin....... In postabsorptive, healthy young men (28 +/- 6 yr) synthetic rates for tendon, ligament, muscle, and skin collagen were 0.046 +/- 0.005, 0.040 +/- 0.006, 0.016 +/- 0.002, and 0.037 +/- 0.003%/h, respectively (means +/- SD). In postabsorptive, healthy elderly men (70 +/- 6 yr) the rate of skeletal muscle collagen...... synthesis is greater than in the young (0.023 +/- 0.002%/h, P collagen are similar to those of mixed skeletal muscle protein in the postabsorptive state, whereas the rate for muscle collagen synthesis is much lower in both young and elderly men...

  17. WE-AB-303-04: A Tissue Model of Cherenkov Emission From the Skin Surface During Megavoltage X-Ray Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Wiles, A. N.; Loyalka, S. K. [University of Missouri, Columbia, MO (United States); Izaguirre, E. W. [University of Missouri, Columbia, MO (United States); Baylor Scott & White Health, Temple, TX (United States)

    2015-06-15

    Purpose: To develop a tissue model of Cherenkov radiation emitted from the skin surface during external beam radiotherapy. Imaging Cherenkov radiation emitted from human skin allows visualization of the beam position and potentially surface dose estimates, and our goal is to characterize the optical properties of these emissions. Methods: We developed a Monte Carlo model of Cherenkov radiation generated in a semi-infinite tissue slab by megavoltage x-ray beams with optical transmission properties determined by a two-layered skin model. We separate the skin into a dermal and an epidermal layer in our model, where distinct molecular absorbers modify the Cherenkov intensity spectrum in each layer while we approximate the scattering properties with Mie and Rayleigh scattering from the highly structured molecular organization found in human skin. Results: We report on the estimated distributions of the Cherenkov wavelength spectrum, emission angles, and surface distribution for the modeled irradiated skin surface. The expected intensity distribution of Cherenkov radiation emitted from skin shows a distinct intensity peak around 475 nm, the blue region of the visible spectrum, between a pair of optical absorption bands in hemoglobin and a broad plateau beginning near 600 nm and extending to at least 700 nm where melanin and hemoglobin absorption are both low. We also find that the Cherenkov intensity decreases with increasing angle from the surface normal, the majority being emitted within 20 degrees of the surface normal. Conclusion: Our estimate of the spectral distribution of Cherenkov radiation emitted from skin indicates an advantage to using imaging devices with long wavelength spectral responsivity. We also expect the most efficient imaging to be near the surface normal where the intensity is greatest; although for contoured surfaces, the relative intensity across the surface may appear to vary due to decreasing Cherenkov intensity with increased angle from the

  18. Vitamin D3 synthesis in the entire skin surface of dairy cows despite hair coverage

    DEFF Research Database (Denmark)

    Hymøller, Lone; Jensen, Søren Krogh

    2010-01-01

    synthesis in the skin during exposure to sunlight. Different scenarios have been suggested but never tested in cows; for example, that vitamin D3 is synthesized from sebum on the hair and ingested by cows during grooming or that body areas such as the udder and muzzle that have scant hair exclusively...... hair are not comparable with respect to prevention of vitamin D3 synthesis and that cows, like humans, synthesize vitamin D3 evenly over their body surface. That vitamin D3 should be synthesized from sebum on the hair and obtained by cows as a result of grooming is not supported by the findings......How hair-coated animals such as dairy cows synthesize endogenous vitamin D3 during exposure to summer sunlight has been unclear since vitamin D3 and its relation to sunlight was discovered. The fur of fur-bearing animals is thought to be comparable to clothing in humans, which prevents vitamin D3...

  19. Human skin equivalents for atopic dermatitis : investigating the role of filaggrin in the skin barrier

    NARCIS (Netherlands)

    Drongelen, Vincent van

    2014-01-01

    Atopic Dermatitis (AD) is a frequent occurring inflammatory skin disease causing physical discomfort, social embarrassment and stress. This skin disease is characterized by decreased skin barrier function and various other epidermal changes, as well as immunological changes. A decreased skin barrier

  20. Clinical, histopathological and immunohistochemical assessment of human skin field cancerization before and after photodynamic therapy.

    Science.gov (United States)

    Szeimies, R M; Torezan, L; Niwa, A; Valente, N; Unger, P; Kohl, E; Schreml, S; Babilas, P; Karrer, S; Festa-Neto, C

    2012-07-01

    The field cancerization concept in photodamaged patients suggests that the entire sun-exposed surface of the skin has an increased risk for the development of (pre)-malignant lesions, mainly epithelial tumours. Topical photodynamic therapy (PDT) is a noninvasive therapeutic method for multiple actinic keratosis (AK) with excellent outcome. To evaluate the clinical, histological and immunohistochemical changes in human skin with field cancerization after multiple sessions of PDT with methyl-aminolaevulinate (MAL). Twenty-six patients with photodamaged skin and multiple AK on the face received three consecutive sessions of MAL-PDT with red light (37 J cm(-2)), 1 month apart. Biopsies before and 3 months after the last treatment session were taken from normal-appearing skin on the field-cancerized area. Immunohistochemical stainings were performed for TP-53, procollagen-I, metalloproteinase-1 (MMP-1) and tenascin-C (Tn-C). All 26 patients completed the study. The global score for photodamage improved considerably in all patients (P cancerization after multiple sessions of MAL-PDT is proven. The decrease in severity and extent of keratinocyte atypia associated with a decreased expression of TP-53 suggest a reduced carcinogenic potential of the sun-damaged area. The significant increase of new collagen deposition and the reduction of solar elastosis explain the clinical improvement of photodamaged skin. © 2012 The Authors. BJD © 2012 British Association of Dermatologists.

  1. Biology of Zika Virus Infection in Human Skin Cells.

    Science.gov (United States)

    Hamel, Rodolphe; Dejarnac, Ophélie; Wichit, Sineewanlaya; Ekchariyawat, Peeraya; Neyret, Aymeric; Luplertlop, Natthanej; Perera-Lecoin, Manuel; Surasombatpattana, Pornapat; Talignani, Loïc; Thomas, Frédéric; Cao-Lormeau, Van-Mai; Choumet, Valérie; Briant, Laurence; Desprès, Philippe; Amara, Ali; Yssel, Hans; Missé, Dorothée

    2015-09-01

    Zika virus (ZIKV) is an emerging arbovirus of the Flaviviridae family, which includes dengue, West Nile, yellow fever, and Japanese encephalitis viruses, that causes a mosquito-borne disease transmitted by the Aedes genus, with recent outbreaks in the South Pacific. Here we examine the importance of human skin in the entry of ZIKV and its contribution to the induction of antiviral immune responses. We show that human dermal fibroblasts, epidermal keratinocytes, and immature dendritic cells are permissive to the most recent ZIKV isolate, responsible for the epidemic in French Polynesia. Several entry and/or adhesion factors, including DC-SIGN, AXL, Tyro3, and, to a lesser extent, TIM-1, permitted ZIKV entry, with a major role for the TAM receptor AXL. The ZIKV permissiveness of human skin fibroblasts was confirmed by the use of a neutralizing antibody and specific RNA silencing. ZIKV induced the transcription of Toll-like receptor 3 (TLR3), RIG-I, and MDA5, as well as several interferon-stimulated genes, including OAS2, ISG15, and MX1, characterized by strongly enhanced beta interferon gene expression. ZIKV was found to be sensitive to the antiviral effects of both type I and type II interferons. Finally, infection of skin fibroblasts resulted in the formation of autophagosomes, whose presence was associated with enhanced viral replication, as shown by the use of Torin 1, a chemical inducer of autophagy, and the specific autophagy inhibitor 3-methyladenine. The results presented herein permit us to gain further insight into the biology of ZIKV and to devise strategies aiming to interfere with the pathology caused by this emerging flavivirus. Zika virus (ZIKV) is an arbovirus belonging to the Flaviviridae family. Vector-mediated transmission of ZIKV is initiated when a blood-feeding female Aedes mosquito injects the virus into the skin of its mammalian host, followed by infection of permissive cells via specific receptors. Indeed, skin immune cells, including dermal

  2. Skin-fold thickness, body mass, and obesity indexes and the arterial to skin-surface PO2 gradient.

    Science.gov (United States)

    Rafferty, T D; Morrero, O

    1983-10-01

    Trends in transcutaneous oxygen tension (tcPO2) correlate closely with Pao2 in the absence of circulatory insufficiency. Individual variation, however, in the arterial to skin-surface Po2 gradient (Pao2-tcPo2 gradient) have limited the usefulness of tcPo2 measurements as precise indicators of Pao2. This individual variability in the Pao2-tcPo2 gradient has been speculated as being caused by "skin factors." This study was performed to examine the relationship between skin-fold thickness (triceps and infraclavicular), body mass index, body surface area, and ponderal index and the Pao2-tcPo2 gradient with a view to delineating correction factors that might be useful in increasing the accuracy of tcPo2 as an estimate of the absolute value of the corresponding Pao2. Skin-fold thickness measurements, body mass index, body surface area, and ponderal index were unrelated to the Po2 gradient. This was thought to be primarily due to an inherent inaccuracy of these measurements as indicators of stratum corneum thickness and dermal capillary depth, the major involved variables.

  3. Molecular basis of retinol anti-ageing properties in naturally aged human skin in vivo.

    Science.gov (United States)

    Shao, Y; He, T; Fisher, G J; Voorhees, J J; Quan, T

    2017-02-01

    Retinoic acid has been shown to improve the aged-appearing skin. However, less is known about the anti-ageing effects of retinol (ROL, vitamin A), a precursor of retinoic acid, in aged human skin in vivo. This study aimed to investigate the molecular basis of ROL anti-ageing properties in naturally aged human skin in vivo. Sun-protected buttock skin (76 ± 6 years old, n = 12) was topically treated with 0.4% ROL and its vehicle for 7 days. The effects of topical ROL on skin epidermis and dermis were evaluated by immunohistochemistry, in situ hybridization, Northern analysis, real-time RT-PCR and Western analysis. Collagen fibrils nanoscale structure and surface topology were analysed by atomic force microscopy. Topical ROL shows remarkable anti-ageing effects through three major types of skin cells: epidermal keratinocytes, dermal endothelial cells and fibroblasts. Topical ROL significantly increased epidermal thickness by stimulating keratinocytes proliferation and upregulation of c-Jun transcription factor. In addition to epidermal changes, topical ROL significantly improved dermal extracellular matrix (ECM) microenvironment; increasing dermal vascularity by stimulating endothelial cells proliferation and ECM production (type I collagen, fibronectin and elastin) by activating dermal fibroblasts. Topical ROL also stimulates TGF-β/CTGF pathway, the major regulator of ECM homeostasis, and thus enriched the deposition of ECM in aged human skin in vivo. 0.4% topical ROL achieved similar results as seen with topical retinoic acid, the biologically active form of ROL, without causing noticeable signs of retinoid side effects. 0.4% topical ROL shows remarkable anti-ageing effects through improvement of the homeostasis of epidermis and dermis by stimulating the proliferation of keratinocytes and endothelial cells, and activating dermal fibroblasts. These data provide evidence that 0.4% topical ROL is a promising and safe treatment to improve the naturally aged human skin

  4. Optical coherence tomography to delineate the interactions of PAMAM dendrimers with the porcine skin surface

    Science.gov (United States)

    Judd, Amy M.; Moss, Gary P.; Heylings, Jon; Wan, Ka-Wai; Yang, Ying

    2013-02-01

    Polyamidoamine (PAMAM) dendrimers have been topically applied to the skin and utilised as a permeation enhancer for a range of therapeutic compounds. However, very little is known about the mechanism of enhancement. This study used optical coherence tomography (OCT) to investigate the influence of PAMAM dendrimers to alter surface refractive index (RI) in excised porcine skin. It is revealed that PAMAM dendrimers caused a sporadic disruption and disappearance of the white hyper-reflective band on the skin surface using OCT. Following the decontamination of the treated skin specimens, the entrance signal, resulting in the polarised light reflecting off the keratin of the upper skin strata, returned to normal. Further, PAMAM-induced changes in skin RI was benchmarked against glycerol, a known permeation enhancer and skin clearing agent. Changes in RI with PAMAM were only observed on the skin surface, suggesting that the dendrimer only modulates the outer layers of the stratum corneum. This is substantially different to the observed effect of glycerol, which permeated more deeply into the skin. The non-invasive and non-destructive OCT imaging technique may provide a convenient tool to investigate the mechanism of permeation enhancement and transdermal drug delivery.

  5. Surface modification of electrospun PLGA scaffold with collagen for bioengineered skin substitutes

    Energy Technology Data Exchange (ETDEWEB)

    Sadeghi, A.R., E-mail: sadeghi_av@ymail.com [Materials Research Group, Iranian Academic Center for Education, Culture and Research, (ACECR), Mashhad Branch, Mashhad (Iran, Islamic Republic of); Nokhasteh, S. [Materials Research Group, Iranian Academic Center for Education, Culture and Research, (ACECR), Mashhad Branch, Mashhad (Iran, Islamic Republic of); Molavi, A.M. [Materials Research Group, Iranian Academic Center for Education, Culture and Research, (ACECR), Mashhad Branch, Mashhad (Iran, Islamic Republic of); Materials Engineering Department, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Khorsand-Ghayeni, M. [Materials Research Group, Iranian Academic Center for Education, Culture and Research, (ACECR), Mashhad Branch, Mashhad (Iran, Islamic Republic of); Naderi-Meshkin, H. [Stem Cell and Regenerative Medicine Research Department, Iranian Academic Center for Education, Culture and Research (ACECR), Mashhad Branch, Mashhad (Iran, Islamic Republic of); Mahdizadeh, A. [Nanotechnology Institute, University of Sistan and Baluchestan, Zahedan (Iran, Islamic Republic of)

    2016-09-01

    In skin tissue engineering, surface feature of the scaffolds plays an important role in cell adhesion and proliferation. In this study, non-woven fibrous substrate based on poly (lactic-co-glycolic acid) (PLGA) (75/25) were hydrolyzed in various concentrations of NaOH (0.05 N, 0.1 N, 0.3 N) to increase carboxyl and hydroxyl groups on the fiber surfaces. These functional groups were activated by EDC/NHS to create chemical bonding with collagen. To improve bioactivity, the activated substrates were coated with a collagen solution (2 mg/ml) and cross-linking was carried out using the EDC/NHS in MES buffer. The effectiveness of the method was evaluated by contact angle measurements, porosimetry, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), tensile and degradation tests as well as in vitro cell attachment and cytotoxicity assays. Cell culture results of human dermal fibroblasts (HDF) and keratinocytes cell line (HaCat) revealed that the cells could attach to the scaffold. Further investigation with MTT assay showed that the cell proliferation of HaCat significantly increases with collagen coating. It seems that sufficient stability of collagen on the surface due to proper chemical bonding and cross-linking has increased the bioactivity of surface remarkably which can be promising for bioengineered skin applications. - Highlights: • Surface activation was carried out by hydrolysis of PLGA fibers. • To improve bioactivity, the activated samples were coated with a collagen solution. • Functional groups were activated by EDC/NHS to create chemical bonding with collagen. • Cross-linking of collagen was carried out using EDC/NHS in MES buffer. • The coated samples exhibited better adhesion and proliferation of epidermal cells.

  6. Surface properties of the skin of the pilot whale Globicephala melas.

    Science.gov (United States)

    Baum, Christof; Simon, Frank; Meyer, Wilfried; Fleischer, Lutz-Günther; Siebers, Dietrich; Kacza, Johannes; Seeger, Johannes

    2003-04-01

    On the skin surface of delphinids small biofoulers are challenged to high shear water flow and liquid-vapor interfaces of air-bubbles during jumping. This state of self-cleaning is supported by the even, nano-rough gel-coated epidermal surface of the skin. The present study focussed on the intercellular evolution of gel formation and the chemical composition of the gel smoothing the skin surface of the pilot whale, Globicephala melas, using X-ray photoelectron spectroscopy (XPS) in combination with cryo-scanning electron microscopy (CSM), and transmission electron microscopy (TEM). In the superficial layer of the epidermis, the stratum corneum, intercellular material was shown by electron optical methods to assemble from smaller into larger covalently cross-linked aggregates during the transit of the corneocytes towards the skin surface. XPS measurements showed that the surface of the skin and the intercellular gel included approximately the same amounts of polar groups (especially, free amines and amides) and non-polar groups, corresponding to the presence of lipid droplets dispersed within the jelly material. It was concluded from the results that the gel-coat of the skin surface is a chemically heterogeneous skin product. The advantages of chemically heterogeneous patches contributing to the ablation of traces of the biofouling process are discussed.

  7. The effect of skin aging on the percutaneous penetration of chemicals through human skin

    Energy Technology Data Exchange (ETDEWEB)

    Roskos, K.V.

    1989-01-01

    Despite much research into the mechanisms of cutaneous aging and the identification of significant age-associated biological and biophysical changes within the skin, the question how does aging affect percutaneous absorption (PA) in vivo remains unanswered. The author has made in vivo measurements of PA in young (18-40 years) and old (> 65 years) subjects. Standard radiotracer methodology was employed and PA was quantified from the urinary excretion profiles of {sup 14}C radiolabel (corrected for incomplete renal elimination). Testosterone (TST), estradiol (EST), hydrocortisone (HC), benzoic acid (BA), acetylsalicylic acid (ASA) and caffeine (CAFF) have been studied. Penetration of HC, BA, ASA, and CAFF were significantly lower in aged subjects whereas TST and EST absorption were not distinguishable from the young controls. Thus it appears that aging can affect PA in vivo and that relatively hydrophilic compounds may be most sensitive. Work was done to elucidate whether the observations were related to documented skin aging changes. Cutaneous microcirculation efficiency suspected to decline with increasing age, could not be correlated with the observed penetration changes. However, in vivo infrared spectroscopic studies of aged stratum corneum (SC) reveal a decreased amount of epidermal lipid. The diminished lipid content implies a diminished dissolution medium for compounds administered to the skin surface. They hypothesize that the compounds most affected by a loss of SC lipids would be those compounds whose overall solubility is lowest (compounds with lower octanol-water partition coefficients, eg., HC, BA, ASA and CAFF). Conversely, a diminished lipid content may not affect dissolution into the SC of highly lipophilic compounds (e.g., TST and EST).

  8. In vivo optical coherence tomography of human skin microstructure

    Science.gov (United States)

    Sergeev, Alexander M.; Gelikonov, Valentin M.; Gelikonov, Grigory V.; Feldchtein, Felix I.; Pravdenko, Kirill I.; Shabanov, Dmitry V.; Gladkova, Natalia D.; Pochinko, Vitaly; Zhegalov, V.; Dmitriev, G.; Vazina, I.; Petrova, Galina P.; Nikulin, Nikolai K.

    1994-12-01

    A compact effective optical coherence tomography (OCT) system is presented. It contains approximately equals 0.3 mW superluminescent diode with spectral width 30 nm FWHM (providing approximately equals 15 micrometers longitudinal resolution) and fiber interferometer with integrated longitudinal scanning. The dynamic range 60 dB allows to observe structure of human skin in vivo up to 1.5 mm in depth. A comparison of obtained tomographs with data of histologic analysis of the same samples of the skin have been carried out to identify the observed structures and determine their optical properties. This technique allows one to perform noncontact, noninvasive diagnostic of early stages of different pathological state of the skin, to measure the burn depth and to observe the process of the recovery. Unlike scanning confocal microscopy, OCT is more suitable for an endoscopic investigation of the mucous membranes of hollow organs. Possible diagnostic applications include dermatology, gastroenterology, gynecology, urology, oncology, othorinolaryngology, transplantology. The most promising features are the potential possibility of differential diagnosis of precancer and various types of cancer, estimation of the invasion depth, differential diagnosis of inflammation and dystrophic processes, control of radical operative treatment.

  9. Recovery of latent fingerprints and DNA on human skin.

    Science.gov (United States)

    Färber, Doris; Seul, Andrea; Weisser, Hans-Joachim; Bohnert, Michael

    2010-11-01

    The project "Latent Fingerprints and DNA on Human Skin" was the first systematic research in Europe dealing with detection of fingerprints and DNA left by offenders on the skin of corpses. One thousand samples gave results that allow general statements on the materials and methods used. The tests were carried out according to a uniform trial structure. Fingerprints were deposited by natural donors on corpses. The latent fingerprints were treated with magnetic powder or black fingerprint powder. Afterward, they were lifted with silicone casting material (Isomark(®)) or gelatine foil. All lifts were swabbed to recover DNA. It was possible to visualize comparable and identifiable fingerprints on the skin of corpses (16%). In the same categories, magnetic powder (18.4%) yielded better results than black fingerprint powder (13.6%). The number of comparable and identifiable fingerprints decreased on the lifts (12.7%). Isomark(®) (14.9%) was the better lifting material in comparison with gelatine foil (10.1%). In one-third of the samples, DNA could be extracted from the powdered and lifted latents. Black fingerprint powder delivered the better result with a rate of 2.2% for full DNA profiles and profiles useful for exclusion in comparison with 1.8% for the magnetic powder traces. Isomark(®) (3.1%) yielded better results than gelatine foil (0.6%). © 2010 American Academy of Forensic Sciences.

  10. Electrical characteristics of female and male human skin

    Directory of Open Access Journals (Sweden)

    Kalauzi A.

    2012-01-01

    Full Text Available Bioimpedance spectroscopy (BIS is a popular method for characterizing the electrical properties of biological tissues. In this study, BIS measurement data of female and male human skin were analyzed and compared. The electrical characteristics of tissue were followed according to four-parameters of the Cole-Cole model: low frequency resistance R0; high frequency resistance R∞; relaxation time t and parameter a. Individual electrical characteristics of human skin were determined for 30 women and 30 men. The distribution and one-way analysis of variance (one-way ANOVA of the Cole-Cole parameters R0, R∞, t, a within the human population indicated their different dependence on gender. Parameter a, which is higher in the female subjects (a =0.83±0.03 than in the male subjects (a=0.7±0.05, is strongly dependent on gender (p=0. Parameter R∞ also significantly depends on gender (p=0.002, while t and R0 seem to be slightly related to gender (p>0.05. [Acknowledgments - This work was supported by the Ministry of Education and Science of the Republic of Serbia (41006.

  11. Steroid synthesis by primary human keratinocytes; implications for skin disease

    Energy Technology Data Exchange (ETDEWEB)

    Hannen, Rosalind F., E-mail: r.f.hannen@qmul.ac.uk [Centre for Cutaneous Research, Institute of Cell and Molecular Science, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AT (United Kingdom); Michael, Anthony E. [Centre for Developmental and Endocrine Signalling, Academic Section of Obstetrics and Gynaecology, Division of Clinical Developmental Sciences, 3rd Floor, Lanesborough Wing, St. George' s, University of London, Cranmer Terrace, Tooting, London SW17 0RE (United Kingdom); Jaulim, Adil [Centre for Cutaneous Research, Institute of Cell and Molecular Science, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AT (United Kingdom); Bhogal, Ranjit [Life Science, Unilever R and D Colworth House, Sharnbrook, Bedfordshire MK44 1LQ (United Kingdom); Burrin, Jacky M. [Centre for Endocrinology, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ (United Kingdom); Philpott, Michael P. [Centre for Cutaneous Research, Institute of Cell and Molecular Science, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AT (United Kingdom)

    2011-01-07

    Research highlights: {yields} Primary keratinocytes express the steroid enzymes required for cortisol synthesis. {yields} Normal primary human keratinocytes can synthesise cortisol. {yields} Steroidogenic regulators, StAR and MLN64, are expressed in normal epidermis. {yields} StAR expression is down regulated in eczema and psoriatic epidermis. -- Abstract: Cortisol-based therapy is one of the most potent anti-inflammatory treatments available for skin conditions including psoriasis and atopic dermatitis. Previous studies have investigated the steroidogenic capabilities of keratinocytes, though none have demonstrated that these skin cells, which form up to 90% of the epidermis are able to synthesise cortisol. Here we demonstrate that primary human keratinocytes (PHK) express all the elements required for cortisol steroidogenesis and metabolise pregnenolone through each intermediate steroid to cortisol. We show that normal epidermis and cultured PHK express each of the enzymes (CYP11A1, CYP17A1, 3{beta}HSD1, CYP21 and CYP11B1) that are required for cortisol synthesis. These enzymes were shown to be metabolically active for cortisol synthesis since radiometric conversion assays traced the metabolism of [7-{sup 3}H]-pregnenolone through each steroid intermediate to [7-{sup 3}H]-cortisol in cultured PHK. Trilostane (a 3{beta}HSD1 inhibitor) and ketoconazole (a CYP17A1 inhibitor) blocked the metabolism of both pregnenolone and progesterone. Finally, we show that normal skin expresses two cholesterol transporters, steroidogenic acute regulatory protein (StAR), regarded as the rate-determining protein for steroid synthesis, and metastatic lymph node 64 (MLN64) whose function has been linked to cholesterol transport in steroidogenesis. The expression of StAR and MLN64 was aberrant in two skin disorders, psoriasis and atopic dermatitis, that are commonly treated with cortisol, suggesting dysregulation of epidermal steroid synthesis in these patients. Collectively these data

  12. Detection of human papillomavirus in nonmelanoma skin cancer lesions and healthy perilesional skin in kidney transplant recipients and immunocompetent patients.

    Science.gov (United States)

    Bernat-García, J; Morales Suárez-Varela, M; Vilata-Corell, J J; Marquina-Vila, A

    2014-04-01

    The influence of human papillomavirus (HPV) on the development of nonmelanoma skin cancer (NMSC) is a topic of debate. HPV types from the beta genus (HPV-β) have been most frequently associated with the development of skin cancer. To analyze the prevalence and range of HPV types in NMSC lesions and healthy perilesional skin in immunodepressed and immunocompetent patients and to evaluate the influence of various clinical factors on the prevalence of HPV in skin cancer. Nested polymerase chain reaction and sequencing were used to detect HPV in 120 NMSC samples obtained by biopsy from 30 kidney transplant recipients and 30 immunocompetent patients. In all cases, a sample was taken from the tumor site and the surrounding healthy skin. Potential confounders were assessed and the data analyzed by multivariate logistic regression. HPV DNA was detected in 44 (73.3%) of the 60 samples from immunodepressed patients and in 32 (53.3%) of the 60 samples from immunocompetent patients (adjusted odds ratio, 3.4; 95% CI, 1.2-9.6). In both groups of patients, HPV was more common in healthy perilesional skin than in lesional skin. HPV-β was the most common type isolated. We found a wide range of HPV types (mostly HPV-β) in the skin of kidney transplant recipients and immunocompetent patients with skin cancer. Copyright © 2013 Elsevier España, S.L. and AEDV. All rights reserved.

  13. Measurement of interstitial cetirizine concentrations in human skin: correlation of drug levels with inhibition of histamine-induced skin responses.

    Science.gov (United States)

    Petersen, L J; Church, M K; Rihoux, J P; Skov, P S

    1999-06-01

    The purpose of the present study was to measure the concentrations of cetirizine in the extracellular water compartment in intact human skin and assess simultaneously inhibition of histamine-induced wheal and flare reactions. Skin cetirizine levels were collected by the microdialysis technique and analyzed by high-pressure liquid chromatography with mass spectrometry detection. Skin levels in 20 subjects were compared to plasma levels for 4 h after a single oral dose of 10 or 20 mg of cetirizine. Skin prick tests were performed with histamine 100 mg/ml. Plasma cetirizine levels increased within 30 min to reach peak values of 315+/-10 and 786+/-45 ng/ml 90-120 min after administration of 10 and 20 mg of cetirizine. This was followed by a slow decline. In the skin, dialysate cetirizine levels (non-protein-bound fraction only) peaked at 1.6+/-0.1 and 2.4+/-0.3 ng/ml at 120-180 min. In vivo recovery of cetirizine was 14.4+/-4.3%. It was estimated that the non-protein-bound concentration of cetirizine in the skin was 50-70% of corresponding plasma values. Both 10- and 20-mg doses of cetirizine inhibited wheal and flare reactions over 240 min. The time vs concentration profile of cetirizine in skin dialysate paralleled the inhibition of skin reactions, but no significant correlations were found between individual cetirizine levels in skin or plasma with wheal and flare reactions. Cetirizine concentrations in the skin could be monitored by the microdialysis technique. The results indicate no simple linear correlation between cetirizine skin levels and inhibition of skin reactions.

  14. Vibrational spectroscopy and microscopic imaging: novel approaches for comparing barrier physical properties in native and human skin equivalents

    Science.gov (United States)

    Yu, Guo; Zhang, Guojin; Flach, Carol R.; Mendelsohn, Richard

    2013-06-01

    Vibrational spectroscopy and imaging have been used to compare barrier properties in human skin, porcine skin, and two human skin equivalents, Epiderm 200X with an enhanced barrier and Epiderm 200 with a normal barrier. Three structural characterizations were performed. First, chain packing and conformational order were compared in isolated human stratum corneum (SC), isolated porcine SC, and in the Epiderm 200X surface layers. The infrared (IR) spectrum of isolated human SC revealed a large proportion of orthorhombically packed lipid chains at physiological temperatures along with a thermotropic phase transition to a state with hexagonally packed chains. In contrast, the lipid phase at physiological temperatures in both porcine SC and in Epiderm 200X, although dominated by conformationally ordered chains, lacked significant levels of orthorhombic subcell packing. Second, confocal Raman imaging of cholesterol bands showed extensive formation of cholesterol-enriched pockets within the human skin equivalents (HSEs). Finally, IR imaging tracked lipid barrier dimensions as well as the spatial disposition of ordered lipids in human SC and Epiderm 200X. These approaches provide a useful set of experiments for exploring structural differences between excised human skin and HSEs, which in turn may provide a rationale for the functional differences observed among these preparations.

  15. Cell surface carbohydrate changes during embryonic and fetal skin development

    DEFF Research Database (Denmark)

    Dabelsteen, Erik; Holbrook, K; Clausen, H

    1986-01-01

    Monoclonal antibodies to four type 2 chain carbohydrate antigens were used for immunohistochemical studies of embryonic and fetal skin. The antibodies detected N-acetyllactosamine and 3 fucosyl substitutes of this, blood group antigen H, Lex, and Ley. Periderm consistently stained for N...

  16. Volumetric cutaneous microangiography of human skin in vivo by VCSEL swept-source optical coherence tomography

    Energy Technology Data Exchange (ETDEWEB)

    Woo June Choi; Wang, R K [University of Washington, Department of Bioengineering, Seattle, Washington 98195 (United States)

    2014-08-31

    We demonstrate volumetric cutaneous microangiography of the human skin in vivo that utilises 1.3-μm high-speed sweptsource optical coherence tomography (SS-OCT). The swept source is based on a micro-electro-mechanical (MEMS)-tunable vertical cavity surface emission laser (VCSEL) that is advantageous in terms of long coherence length over 50 mm and 100 nm spectral bandwidth, which enables the visualisation of microstructures within a few mm from the skin surface. We show that the skin microvasculature can be delineated in 3D SS-OCT images using ultrahigh-sensitive optical microangiography (UHS-OMAG) with a correlation mapping mask, providing a contrast enhanced blood perfusion map with capillary flow sensitivity. 3D microangiograms of a healthy human finger are shown with distinct cutaneous vessel architectures from different dermal layers and even within hypodermis. These findings suggest that the OCT microangiography could be a beneficial biomedical assay to assess cutaneous vascular functions in clinic. (laser biophotonics)

  17. 'Nosing Around' the human skin: what information is concealed in skin odour?

    Science.gov (United States)

    Kippenberger, Stefan; Havlíček, Jan; Bernd, August; Thaçi, Diamant; Kaufmann, Roland; Meissner, Markus

    2012-09-01

    In today's world, natural body odour is mostly considered as being unpleasant and combated by intensive cleansing, deodorants and perfumes. However, there is evidence that volatile body compounds provide the recipient with important information. Here, we present the chemical identity of odorous compounds derived from odourless precursors within sweat and sebum. Moreover, distinct volatile markers may be relevant for the clinical diagnosis of disease. Interestingly, ageing seems to correlate with the appearance of specific compounds that convey the so-called old man smell. Finally, it is discussed if human skin odour has the quality to act as pheromone transmitting information between individuals in terms of major histocompatibility complex type or reproductive status. © 2012 John Wiley & Sons A/S.

  18. Fractional Calculus Model of Electrical Impedance Applied to Human Skin

    Science.gov (United States)

    Vosika, Zoran B.; Lazovic, Goran M.; Misevic, Gradimir N.; Simic-Krstic, Jovana B.

    2013-01-01

    Fractional calculus is a mathematical approach dealing with derivatives and integrals of arbitrary and complex orders. Therefore, it adds a new dimension to understand and describe basic nature and behavior of complex systems in an improved way. Here we use the fractional calculus for modeling electrical properties of biological systems. We derived a new class of generalized models for electrical impedance and applied them to human skin by experimental data fitting. The primary model introduces new generalizations of: 1) Weyl fractional derivative operator, 2) Cole equation, and 3) Constant Phase Element (CPE). These generalizations were described by the novel equation which presented parameter related to remnant memory and corrected four essential parameters We further generalized single generalized element by introducing specific partial sum of Maclaurin series determined by parameters We defined individual primary model elements and their serial combination models by the appropriate equations and electrical schemes. Cole equation is a special case of our generalized class of models for Previous bioimpedance data analyses of living systems using basic Cole and serial Cole models show significant imprecisions. Our new class of models considerably improves the quality of fitting, evaluated by mean square errors, for bioimpedance data obtained from human skin. Our models with new parameters presented in specific partial sum of Maclaurin series also extend representation, understanding and description of complex systems electrical properties in terms of remnant memory effects. PMID:23577065

  19. Boron Diffused Thermoluminescent Surface Layer in LiF TLDs for Skin Dose Assessments

    DEFF Research Database (Denmark)

    Christensen, Poul; Majborn, Benny

    1980-01-01

    A new high-temperature glow peak produced in a thin surface layer of LiF TLDs by diffusion of boron into the LiF material has been studied for skin dose assessments in personnel dosimetry.......A new high-temperature glow peak produced in a thin surface layer of LiF TLDs by diffusion of boron into the LiF material has been studied for skin dose assessments in personnel dosimetry....

  20. Aluminum is More Cytotoxic than Lunar Dust in Human Skin and Lung Fibroblasts

    Science.gov (United States)

    Hammond, D.; Shehata, T.; Hammond, D.; Shehata, T.; Wise, J.P.; Martino, J; Wise, J.P.; Wise, J.P.

    2009-01-01

    NASA plans to build a permanent space station on the moon to explore its surface. The surface of the moon is covered in lunar dust, which consists of fine particles that contain silicon, aluminum and titanium, among others. Because this will be a manned base, the potential toxicity of this dust has to be studied. Also, toxicity standards for potential exposure have to be set. To properly address the potential toxicity of lunar dust we need to understand the toxicity of its individual components, as well as their combined effects. In order to study this we compared NASA simulant JSC-1AVF (volcanic ash particles), that simulates the dust found on the moon, to aluminum, the 3rd most abundant component in lunar dust. We tested the cytotoxicity of both compounds on human lung and skin fibroblasts (WTHBF-6 and BJhTERT cell lines, respectively). Aluminum oxide was more cytotoxic than lunar dust to both cell lines. In human lung fibroblasts 5, 10 and 50 g/sq cm of aluminum oxide induced 85%, 61% and 30% relative survival, respectively. For human skin fibroblasts the same concentrations induced 58%, 41% and 58% relative survival. Lunar dust was also cytotoxic to both cell lines, but its effects were seen at higher concentrations: 50, 100, 200 and 400 g/sq cm of lunar dust induced a 69%, 46%, 35% and 30% relative survival in the skin cells and 53%, 16%, 8% and 2% on the lung cells. Overall, for both compounds, lung cells were more sensitive than skin cells. This work was supported by a NASA EPSCoR grant through the Maine Space Grant Consortium (JPW), the Maine Center for Toxicology and Environmental Health., a Fulbright Grant (JM) and a Delta Kappa Gamma Society International World Fellowship (JM).

  1. Laser system for optical biopsy and in-vivo study of the human skin

    Science.gov (United States)

    Borisova, Ekaterina G.; Avramov, Lachezar A.

    2001-04-01

    The aim of this study was to perform a preliminary evaluation of the diagnostic potential of noninvasive laser-induced autofluorescence spectroscopy (LIAFS) for human skin in vivo. The autofluorescence characterization of tissue relies on different spectral properties of tissue. It was demonstrated a differentiation between normal skin and skin with vitaligo. In our experimental investigation of the autofluorescence spectrum of human skin in vivo a nitrogen laser with excitation wavelength 337 nm was used. Two fluorescence bands were observed at 440 and 490 nm, these were attributed to reduced nicotinamide adenine dinucleotide (NADH) and collagen. The intensity of the NADH emission band was markedly reduced in the skin with vitaligo compared with the normal skin, which could indicate different redox conditions in skin with vitaligo. The autofluorescence spectrum of human skin depends on the main internal absorbers, which are blood and melanin. In this study was described the effect caused by melanin content on the shape of the autofluorescence spectrum of human skin. Human skin fluorescence spectrum might provide dermatologists with important information and such investigations are successfully used now in skin disease diagnostics, in investigation of the environmental factor impact or for evaluation of treatment efficiency. The goal of this work is optimization of detection and diagnosis of hollow organs and skin.

  2. Genetic deletion of amphiregulin restores the normal skin phenotype in a mouse model of the human skin disease tylosis

    Directory of Open Access Journals (Sweden)

    Vishnu Hosur

    2017-08-01

    Full Text Available In humans, gain-of-function (GOF mutations in RHBDF2 cause the skin disease tylosis. We generated a mouse model of human tylosis and show that GOF mutations in RHBDF2 cause tylosis by enhancing the amount of amphiregulin (AREG secretion. Furthermore, we show that genetic disruption of AREG ameliorates skin pathology in mice carrying the human tylosis disease mutation. Collectively, our data suggest that RHBDF2 plays a critical role in regulating EGFR signaling and its downstream events, including development of tylosis, by facilitating enhanced secretion of AREG. Thus, targeting AREG could have therapeutic benefit in the treatment of tylosis.

  3. Optical discrimination of surface reflection from volume backscattering in speckle contrast for skin roughness measurements

    Science.gov (United States)

    Tchvialeva, Lioudmila; Zeng, Haishan; Markhvida, Igor; Dhadwal, Gurbir; McLean, Lianne; McLean, David I.; Lui, Harvey; Lee, Tim K.

    2009-02-01

    Background: The intermixing of light reflected from tissue surface and scattered from tissue volume complicates skin surface roughness assessment by laser speckle technique, a non-invasive optical method based on the analysis of the contrast of a speckle pattern. Objective: In this study we investigated optical discrimination methods to separate the two contributions in a speckle pattern. Methods: Three discrimination methods, spatial, polarization and spectral filtering, were implemented to suppress light from skin internal volume in a laser speckle device. In order to determine the effectiveness of the discrimination methods, speckle patterns were obtained from healthy volunteers, and polychromatic speckle contrast was computed before and after each filtering procedure. Results: Speckle contrast increased after discrimination filtering. A simple formula was derived to calculate the speckle contrast associated with light scattered from the skin surface. This corrected speckle contrast was proposed to be used for skin roughness assessment.

  4. The long-term use of soap does not affect the pH-maintenance mechanism of human skin.

    Science.gov (United States)

    Takagi, Y; Kaneda, K; Miyaki, M; Matsuo, K; Kawada, H; Hosokawa, H

    2015-05-01

    The pH at the surface of healthy human skin is around 5. Cleansing the skin with soap increases the pH of the skin, which then returns to a more acidic pH within a few hours. However, the effects of skin cleansing with soap over a long time on the pH regulatory system is still unclear. We compared the pH of the skin between users of a soap-based cleanser and of a mild-acidic cleanser prior to and following the cleansing. This study had two groups of subjects, one group who had used a soap-based cleanser for more than 5 years and the other group who had used a mild-acidic cleanser for more than 5 years. The pH on the inner forearm of each subject was measured prior to and for 6 h after cleansing with a soap bar. There were no differences between the pH of the skin these two groups prior to cleansing, immediately after cleansing or in the pH recovery rate for 6 h. These results suggest that long-term continuous use of a soap-based cleanser does not affect the pH-maintaining mechanism of human skin. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. THz time-domain spectroscopy of human skin tissue for in-body nanonetworks

    OpenAIRE

    Chopra, Nishtha; Yang, Ke; Qammer H. Abbasi; Qaraqe, Khalid A.; Philpott, Mike; Alomainy, Akram

    2016-01-01

    This paper presents experimental study of real human skin material parameter extraction based on terahertz (THz) time-domain spectroscopy in the band 0.1-2.5 THz. Results in this paper show that electromagnetic properties of the human skin distinctively affect the path loss and noise temperature parameters of the communication link, which are vital for channel modeling of in-body nanonetworks. Refractive index and absorption coefficient values are evaluated for dermis layer of the human skin....

  6. Real-time trace gas sensing of ethylene, propanal and acetaldehyde from human skin in vivo.

    NARCIS (Netherlands)

    Moeskops, B.W.M.; Steeghs, M.M.L.; Swam, K. van; Cristescu, S.M.; Scheepers, P.T.J.; Harren, F.J.M.

    2006-01-01

    Trace gases emitted by human skin in vivo are monitored non-invasively and in real time using laser-based photoacoustic detection and proton-transfer reaction mass spectrometry. A small quartz cuvette is placed on the skin to create a headspace from which a carrier gas transports the skin emissions

  7. Color reproduction of human skin by spectral reflectance using RGB images and the Wiener estimation method

    Science.gov (United States)

    Sato, Kiyomi; Miyazawa, Shota; Funamizu, Hideki; Yuasa, Tomonori; Nishidate, Izumi; Aizu, Yoshihisa

    2017-04-01

    Skin measurements based on spectral reflectance are widely studied in the fields of medical care and cosmetics. It has the advantage that several skin properties can be estimated in the non-invasive and non-contacting manner. In this study, we demonstrate the color reproduction of human skin by spectral reflectance using RGB images and the Wiener estimation method.

  8. In situ depletion of CD4(+) T cells in human skin by Zanolimumab

    DEFF Research Database (Denmark)

    Villadsen, L.S.; Skov, L.; Dam, T.N.

    2007-01-01

    -driving T cells in situ may therefore be a useful approach in the treatment of inflammatory and malignant skin diseases. Depletion of CD4(+) T cells in intact inflamed human skin tissue by Zanolimumab, a fully human therapeutic monoclonal antibody (IgG1, kappa) against CD4, was studied in a human psoriasis...

  9. Changes of human skin in subepidermal wound healing process.

    Science.gov (United States)

    Sugata, Keiichi; Kitahara, Takashi; Takema, Yoshinori

    2008-11-01

    The wound healing process involves unexplained mechanisms. An aberration in this process is known to cause dermal disorders such as keloid or hypertrophic scars, but the mechanism by which these scars are formed remains to be elucidated. Here we examined the usefulness of a non-invasive optical imaging device to clarify mechanisms of wound healing and of scar formation. An 8 mm experimental wound was made in the forearms of six subjects by a suction blister method. To observe chronological changes associated with wound healing, horizontal cross-sectional images were non-invasively obtained of the wounded area from the skin surface down to 129 microm below at 21.5 microm intervals using in vivo laser confocal scanning microscopy (LCSM). The wounds were covered with a new epidermis by week 2, at which time the dermal papilla count decreased while the thickness from the skin surface to the apex of the dermal papilla increased. The count and the thickness returned to the initial levels when the wound was healed. In two out of six subjects, fibrous tissues were observed in the upper dermis, whereas in one other subject, melanocyte-like dendritic cells were observed in the epidermis-dermis border in later phases of wound healing. This non-invasive method using in vivo LCSM revealed chronological changes in the dermis and epidermis during wound healing. In addition, although a scar was not formed in any of study subjects, this microscopy revealed aspects similar to the fibrous tissue overgrowth or to melanocyte migration, both of which may relate to wound healing. These results indicate the usefulness of this non-invasive method in studies of wound healing and of scar formation.

  10. Teleost skin, an ancient mucosal surface that elicits gut-like immune responses.

    Science.gov (United States)

    Xu, Zhen; Parra, David; Gómez, Daniela; Salinas, Irene; Zhang, Yong-An; von Gersdorff Jørgensen, Louise; Heinecke, Rasmus Demuth; Buchmann, Kurt; LaPatra, Scott; Sunyer, J Oriol

    2013-08-06

    Skin homeostasis is critical to preserve animal integrity. Although the skin of most vertebrates is known to contain a skin-associated lymphoid tissue (SALT), very little is known about skin B-cell responses as well as their evolutionary origins. Teleost fish represent the most ancient bony vertebrates containing a SALT. Due to its lack of keratinization, teleost skin possesses living epithelial cells in direct contact with the water medium. Interestingly, teleost SALT structurally resembles that of the gut-associated lymphoid tissue, and it possesses a diverse microbiota. Thus, we hypothesized that, because teleost SALT and gut-associated lymphoid tissue have probably been subjected to similar evolutionary selective forces, their B-cell responses would be analogous. Confirming this hypothesis, we show that IgT, a teleost immunoglobulin specialized in gut immunity, plays the prevailing role in skin mucosal immunity. We found that IgT(+) B cells represent the major B-cell subset in the skin epidermis and that IgT is mainly present in polymeric form in the skin mucus. Critically, we found that the majority of the skin microbiota are coated with IgT. Moreover, IgT responses against a skin parasite were mainly limited to the skin whereas IgM responses were almost exclusively detected in the serum. Strikingly, we found that the teleost skin mucosa showed key features of mammalian mucosal surfaces exhibiting a mucosa-associated lymphoid tissue. Thus, from an evolutionary viewpoint, our findings suggest that, regardless of their phylogenetic origin and tissue localization, the chief immunoglobulins of all mucosa-associated lymphoid tissue operate under the guidance of primordially conserved principles.

  11. Three-dimensional hierarchical cultivation of human skin cells on bio-adaptive hybrid fibers.

    Science.gov (United States)

    Planz, Viktoria; Seif, Salem; Atchison, Jennifer S; Vukosavljevic, Branko; Sparenberg, Lisa; Kroner, Elmar; Windbergs, Maike

    2016-07-11

    The human skin comprises a complex multi-scale layered structure with hierarchical organization of different cells within the extracellular matrix (ECM). This supportive fiber-reinforced structure provides a dynamically changing microenvironment with specific topographical, mechanical and biochemical cell recognition sites to facilitate cell attachment and proliferation. Current advances in developing artificial matrices for cultivation of human cells concentrate on surface functionalizing of biocompatible materials with different biomolecules like growth factors to enhance cell attachment. However, an often neglected aspect for efficient modulation of cell-matrix interactions is posed by the mechanical characteristics of such artificial matrices. To address this issue, we fabricated biocompatible hybrid fibers simulating the complex biomechanical characteristics of native ECM in human skin. Subsequently, we analyzed interactions of such fibers with human skin cells focusing on the identification of key fiber characteristics for optimized cell-matrix interactions. We successfully identified the mediating effect of bio-adaptive elasto-plastic stiffness paired with hydrophilic surface properties as key factors for cell attachment and proliferation, thus elucidating the synergistic role of these parameters to induce cellular responses. Co-cultivation of fibroblasts and keratinocytes on such fiber mats representing the specific cells in dermis and epidermis resulted in a hierarchical organization of dermal and epidermal tissue layers. In addition, terminal differentiation of keratinocytes at the air interface was observed. These findings provide valuable new insights into cell behaviour in three-dimensional structures and cell-material interactions which can be used for rational development of bio-inspired functional materials for advanced biomedical applications.

  12. Heat Transfer in Human Skin Exposed to Radiation from Forest Fire Taking Into Account Moisture Evaporation

    Directory of Open Access Journals (Sweden)

    Poptsov Nikolay

    2017-01-01

    Full Text Available Thermal radiation is one of the damaging factors of forest fire. As a result of exposure to radiant heat flow, thermal damage of the human skin is possible. A layer of skin is considered with effective thermophysical characteristics. Thin layer of sweat excretion situated on top of the skin. A mathematical model of heat transfer in the system of “skin-excretion” is developed taking into account evaporation of moisture. Typical simulation results are presented.

  13. Stress-induced responses of human skin fibroblasts in vitro reflect human longevity

    NARCIS (Netherlands)

    Dekker, Pim; Maier, Andrea B.; van Heemst, Diana; de Koning-Treurniet, Corine; Blom, Joke; Dirks, Roeland W.; Tanke, Hans J.; Westendorp, Rudi G.J.

    2009-01-01

    Unlike various model organisms, cellular responses to stress have not been related to human longevity. We investigated cellular responses to stress in skin fibroblasts that were isolated from young and very old subjects, and from offspring of nonagenarian siblings and their partners, representatives

  14. Skin Friction Reduction Characteristics of Nonsmooth Surfaces Inspired by the Shapes of Barchan Dunes

    Directory of Open Access Journals (Sweden)

    Xiao-wen Song

    2017-01-01

    Full Text Available A new type of nonsmooth surface inspired by the shape of barchan dunes has been proposed and is intended to reduce skin friction, a major cause of overall drag. Simulations were carried out to obtain skin friction reduction characteristics for the nonsmooth surface using the commercial computational fluid dynamics software Fluent. A realizable k-ε model was employed to assess the influence of the nonsmooth structure on turbulent flow and velocity fields. The numerical simulation results showed that the new nonsmooth surface possesses the desired skin friction reduction effect and that the maximum skin friction reduction percentage reached 33.63% at a fluid speed of 30 m/s. Various aspects of the skin friction reduction mechanism were discussed, including the distribution of velocity vectors and shear stress contours and the variations in boundary layer thickness. The accuracy of the flow field for the nonsmooth unit was further verified by particle image velocimetry test results. The new bionic nonsmooth surface, which exceeds the limitations of existing nonsmooth bionic structures, can effectively reduce skin friction and should provide insights into engineering applications in the future.

  15. Characterizing human skin blood flow regulation in response to different local skin temperature perturbations.

    Science.gov (United States)

    Wu, Y; Nieuwenhoff, M D; Huygen, F J P M; van der Helm, F C T; Niehof, S; Schouten, A C

    2017-05-01

    Small nerve fibers regulate local skin blood flow in response to local thermal perturbations. Small nerve fiber function is difficult to assess with classical neurophysiological tests. In this study, a vasomotor response model in combination with a heating protocol was developed to quantitatively characterize the control mechanism of small nerve fibers in regulating skin blood flow in response to local thermal perturbation. The skin of healthy subjects' hand dorsum (n=8) was heated to 42°C with an infrared lamp, and then naturally cooled down. The distance between the lamp and the hand was set to three different levels in order to change the irradiation intensity on the skin and implement three different skin temperature rise rates (0.03°C/s, 0.02°C/s and 0.01°C/s). A laser Doppler imager (LDI) and a thermographic video camera recorded the temporal profile of the skin blood flow and the skin temperature, respectively. The relationship between the skin blood flow and the skin temperature was characterized by a vasomotor response model. The model fitted the skin blood flow response well with a variance accounted for (VAF) between 78% and 99%. The model parameters suggested a similar mechanism for the skin blood flow regulation with the thermal perturbations at 0.03°C/s and 0.02°C/s. But there was an accelerated skin vasoconstriction after a slow heating (0.01°C/s) (p-valueskin vasodilation was also observed in four out of the seven subjects during the slow heating (0.01°C/s). Our method provides a promising way to quantitatively assess the function of small nerve fibers non-invasively and non-contact. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  16. Instrumentation for the measurement of autofluorescence in the human skin

    NARCIS (Netherlands)

    Graaff, R; Meerwaldt, R; Lutgers, HL; Baptist, R; de Jong, ED; Zijp, [No Value; Links, TP; Smit, AJ; Rakhorst, G; VoDinh, T; Grundfest, WS; Benaron, DA; Cohn, GE

    2005-01-01

    A setup to measure skin autofluorescence was developed to assess accumulation of advanced glycation endproducts (AGE) in patients noninvasively. The method applies direct blacklight tube illumination of the skin of the lower arm, and spectrometry. The setup displays skin autofluorescence (AF) as a

  17. The effect of surface wave propagation on neural responses to vibration in primate glabrous skin.

    Directory of Open Access Journals (Sweden)

    Louise R Manfredi

    Full Text Available Because tactile perception relies on the response of large populations of receptors distributed across the skin, we seek to characterize how a mechanical deformation of the skin at one location affects the skin at another. To this end, we introduce a novel non-contact method to characterize the surface waves produced in the skin under a variety of stimulation conditions. Specifically, we deliver vibrations to the fingertip using a vibratory actuator and measure, using a laser Doppler vibrometer, the surface waves at different distances from the locus of stimulation. First, we show that a vibration applied to the fingertip travels at least the length of the finger and that the rate at which it decays is dependent on stimulus frequency. Furthermore, the resonant frequency of the skin matches the frequency at which a subpopulation of afferents, namely Pacinian afferents, is most sensitive. We show that this skin resonance can lead to a two-fold increase in the strength of the response of a simulated afferent population. Second, the rate at which vibrations propagate across the skin is dependent on the stimulus frequency and plateaus at 7 m/s. The resulting delay in neural activation across locations does not substantially blur the temporal patterning in simulated populations of afferents for frequencies less than 200 Hz, which has important implications about how vibratory frequency is encoded in the responses of somatosensory neurons. Third, we show that, despite the dependence of decay rate and propagation speed on frequency, the waveform of a complex vibration is well preserved as it travels across the skin. Our results suggest, then, that the propagation of surface waves promotes the encoding of spectrally complex vibrations as the entire neural population is exposed to essentially the same stimulus. We also discuss the implications of our results for biomechanical models of the skin.

  18. Influence of the complex of retinol-vitamin C on skin surface lipids.

    Science.gov (United States)

    Wójcik, Aneta; Bartnicka, Ewelina; Namieciński, Piotr; Rotsztejn, Helena

    2015-06-01

    Retinol is used to reduce symptoms of skin aging. It affects surface lipids and increases skin regeneration ability. The aim of our study was to investigate the effect of retinol peel on the face and neck skin lipids in women, aged 50-69. The level of secreted sebum was measured using Sebumeter SM15 (Courage & Khazaka, Germany) on the forehead, cheeks, nose, chin, and neck. The measurements were carried out before each of the 3 retinol peel treatments applied at 3-week interval and 3 weeks after the last treatment. A statistically significant increase of lipid film in both U-zone and T-zone and on the neck was observed in the study group. Retinol peel treatments can help to increase the amount of skin surface lipids in women during menopause. © 2015 Wiley Periodicals, Inc.

  19. Permeation of chromium salts through human skin in vitro

    DEFF Research Database (Denmark)

    Gammelgaard, Bente; Fullerton, A; Avnstorp, C

    1992-01-01

    of the dichromate solution. Chromium skin levels increased with increasing concentrations of applied chromium salts up to 0.034 M Cr. The amount of chromium in recipient phase and skin layers increased with increasing pH when the applied solution contained potassium dichromate. This was ascribed to a decreased skin...... barrier function of the skin. The amount of chromium found in all skin layers after application of chromium chloride decreased with increasing pH due to lower solubility of the salt. The % of chromium found in the recipient phase as chromium(VI) increased with increasing total chromium concentration...

  20. Biological evaluation of human hair keratin scaffolds for skin wound repair and regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Songmei; Sang, Lin [National Engineering Research Center for Biomaterials, Sichuan University, Chengdu 610064 (China); Zhang, Yaping [Engineering Research Center of Biomass Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010 (China); Wang, Xiaoliang [National Engineering Research Center for Biomaterials, Sichuan University, Chengdu 610064 (China); Li, Xudong, E-mail: xli20004@yahoo.com [National Engineering Research Center for Biomaterials, Sichuan University, Chengdu 610064 (China)

    2013-03-01

    The cytocompatibility, in vivo biodegradation and wound healing of keratin biomaterials were investigated. For the purposes, three groups of keratin scaffolds were fabricated by freeze-drying reduced solutions at 2 wt.%, 4 wt.% and 8 wt.% keratins extracted from human hairs. These scaffolds exhibited evenly distributed high porous structures with pore size of 120-220 {mu}m and the porosity > 90%. NIH3T3 cells proliferated well on these scaffolds in culture lasting up to 22 days. Confocal micrographs stained with AO visually revealed cell attachment and infiltration as well as scaffold architectural stability. In vivo animal experiments were conducted with 4 wt.% keratin scaffolds. Early degradation of subcutaneously implanted scaffolds occurred at 3 weeks in the outermost surface, in concomitant with inflammatory response. At 5 weeks, the overall porous structure of scaffolds severely deteriorated while the early inflammatory response in the outermost surface obviously subsided. A faster keratin biodegradation was observed in repairing full-thickness skin defects. Compared with the blank control, keratin scaffolds gave rise to more blood vessels at 2 weeks and better complete wound repair at 3 weeks with a thicker epidermis, less contraction and newly formed hair follicles. These preliminary results suggest that human hair keratin scaffolds are promising dermal substitutes for skin regeneration. - Highlights: Black-Right-Pointing-Pointer Preparation of highly-interconnected human hair keratin scaffolds. Black-Right-Pointing-Pointer Long-term cell culturing and in vivo animal experiments with keratin scaffolds. Black-Right-Pointing-Pointer Biodegradation is dependent on implantation site and function Black-Right-Pointing-Pointer Early vascularization and better repair in treating full-thickness skin wounds. Black-Right-Pointing-Pointer A thicker epidermis, less contraction and newly formed hair follicles are observed.

  1. Terahertz pulse imaging in reflection geometry of human skin cancer and skin tissue

    Energy Technology Data Exchange (ETDEWEB)

    Woodward, Ruth M [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge (United Kingdom); Cole, Bryan E [TeraView Limited, 302/304 Cambridge Science Park, Milton Road, Cambridge (United Kingdom); Wallace, Vincent P [TeraView Limited, 302/304 Cambridge Science Park, Milton Road, Cambridge (United Kingdom); Pye, Richard J [Department of Dermatology, Addenbrooke' s Hospital, Cambridge (United Kingdom); Arnone, Donald D [TeraView Limited, 302/304 Cambridge Science Park, Milton Road, Cambridge (United Kingdom); Linfield, Edmund H [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge (United Kingdom); Pepper, Michael [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge (United Kingdom)

    2002-11-07

    We demonstrate the application of terahertz pulse imaging (TPI) in reflection geometry for the study of skin tissue and related cancers both in vitro and in vivo. The sensitivity of terahertz radiation to polar molecules, such as water, makes TPI suitable for studying the hydration levels in the skin and the determination of the lateral spread of skin cancer pre-operatively. By studying the terahertz pulse shape in the time domain we have been able to differentiate between diseased and normal tissue for the study of basal cell carcinoma (BCC). Basal cell carcinoma has shown a positive terahertz contrast, and inflammation and scar tissue a negative terahertz contrast compared to normal tissue. In vivo measurements on the stratum corneum have enabled visualization of the stratum corneum-epidermis interface and the study of skin hydration levels. These results demonstrate the potential of terahertz pulse imaging for the study of skin tissue and its related disorders, both in vitro and in vivo.

  2. Monomethylarsonous acid inhibited endogenous cholesterol biosynthesis in human skin fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Lei [Environmental Toxicology Graduate Program, University of California, Riverside, CA 92521-0403 (United States); Xiao, Yongsheng [Department of Chemistry, University of California, Riverside, CA 92521-0403 (United States); Wang, Yinsheng, E-mail: yinsheng.wang@ucr.edu [Environmental Toxicology Graduate Program, University of California, Riverside, CA 92521-0403 (United States); Department of Chemistry, University of California, Riverside, CA 92521-0403 (United States)

    2014-05-15

    Human exposure to arsenic in drinking water is a widespread public health concern, and such exposure is known to be associated with many human diseases. The detailed molecular mechanisms about how arsenic species contribute to the adverse human health effects, however, remain incompletely understood. Monomethylarsonous acid [MMA(III)] is a highly toxic and stable metabolite of inorganic arsenic. To exploit the mechanisms through which MMA(III) exerts its cytotoxic effect, we adopted a quantitative proteomic approach, by coupling stable isotope labeling by amino acids in cell culture (SILAC) with LC-MS/MS analysis, to examine the variation in the entire proteome of GM00637 human skin fibroblasts following acute MMA(III) exposure. Among the ∼ 6500 unique proteins quantified, ∼ 300 displayed significant changes in expression after exposure with 2 μM MMA(III) for 24 h. Subsequent analysis revealed the perturbation of de novo cholesterol biosynthesis, selenoprotein synthesis and Nrf2 pathways evoked by MMA(III) exposure. Particularly, MMA(III) treatment resulted in considerable down-regulation of several enzymes involved in cholesterol biosynthesis. In addition, real-time PCR analysis showed reduced mRNA levels of select genes in this pathway. Furthermore, MMA(III) exposure contributed to a distinct decline in cellular cholesterol content and significant growth inhibition of multiple cell lines, both of which could be restored by supplementation of cholesterol to the culture media. Collectively, the present study demonstrated that the cytotoxicity of MMA(III) may arise, at least in part, from the down-regulation of cholesterol biosynthesis enzymes and the resultant decrease of cellular cholesterol content. - Highlights: • MMA(III)-induced perturbation of the entire proteome of GM00637 cells is studied. • Quantitative proteomic approach revealed alterations of multiple cellular pathways. • MMA(III) inhibits de novo cholesterol biosynthesis. • MMA

  3. Skin scrapings versus standardized skin surface biopsy to detect Demodex mites in patients with facial erythema of uncertain cause - a comparative study.

    Science.gov (United States)

    Bunyaratavej, Sumanas; Rujitharanawong, Chuda; Kasemsarn, Pranee; Boonchai, Waranya; Muanprasert, Chanai; Matthapan, Lalita; Leeyaphan, Charussi

    2016-01-01

    Standardized skin surface biopsy (SSSB) is considered to be the gold standard technique to evaluate the density of Demodex mites for the diagnosis of demodicidosis. Potassium hydroxide (KOH) preparation of skin scrapings is a much simpler procedure that can be used to detect pathogens in the superficial skin. To evaluate the reliability of potassium hydroxide preparation of skin scrapings as compared to the standard skin biopsy technique with regard to capacity to detect Demodex mites, time consumed and technician satisfaction. One hundred outpatients presenting with facial erythema of uncertain cause were enrolled. Standardized skin surface biopsy and potassium hydroxide preparation of skin scrapings were undertaken in adjacent areas on the patients' right cheek. Patients with normal facial skin were excluded from the study. The accuracy of Demodex mite detection by potassium hydroxide preparation of skin-scrapings when compared to the standard procedure is 82%. The sensitivity, specificity, positive and negative predictive values of this method are 75%, 84.2%, 60% and 91.43%, respectively. There was no statistically significant difference between the standard and skin scraping techniques (P = 0.238) with regard to mite detection. Mean preparation time while using the skin scraping technique was 6 times less than that of the standard technique. For interpretation also, skin scraping technique (3.6 min) consumed much less time than the biopsy technique (9.8 min). Moreover, experienced technicians were more satisfied with skin scraping. Potassium hydroxide preparation of skin scrapings is an effective, time saving and practical technique to detect Demodex mites with accuracy comparable to the standard biopsy method.

  4. A novel approach to measuring the frictional behaviour of human skin in vivo

    NARCIS (Netherlands)

    Veijgen, N.K.; Masen, Marc Arthur; van der Heide, Emile

    2012-01-01

    Friction involving human skin plays a key role in human life. The availability of a portable tribometer improves the accessibility to large number of both subjects and anatomical sites. This is the first mobile device suitable to measure skin friction with a controlled and variable normal load

  5. Barrier function in reconstructed epidermis and its resemblance to native human skin

    NARCIS (Netherlands)

    Ponec, M.; Gibbs, S.; Pilgram, G.; Boelsma, E.; Koerten, H.; Bouwstra, J.; Mommaas, M.

    2001-01-01

    One of the prerequisites for the use of human skin equivalents for scientific and screening purposes is that their barrier function is similar to that of native skin. Using human epidermis reconstructed on de-epidermized dermis we demonstrated that the formation of the stratum corneum (SC) barrier

  6. Barrier Ëunction in Reconstructed Epidermis and Its Resembiance to Native Human Skin

    NARCIS (Netherlands)

    Ponec, M.; Gibbs, S.; GPilgram, G.; BoeIsma, E.; Koerten, H.; Bouwstra, J.; Mommaas, M.

    2001-01-01

    One of the prerequisitesforthe use of human skin equivalents for scientific and screening purposes is that their barrierfunction is similar to that of native skin. Using human epidermis reconstructed en de-epidermized dermis we demonstrated that the formation of the stratum corneum (SC) barrier in

  7. Skin Deep: Highlights of NREL Surface Analysis PV Research

    Energy Technology Data Exchange (ETDEWEB)

    Asher, S.; Pankow, J.; Perkins, C.; Reedy, R.; Teeter, G.; Young, M.

    2005-11-01

    The Surface Analysis project provides measurement support and leadership for collaborative research activities involving surface chemistry and physics in all areas of the PV program. Significant results from the past fiscal year include the following: i) in-situ XPS, UPS, and AES studies of chemical-bath exposure of CIGS surfaces demonstrated that Group-III elements are preferentially removed from the surface, that type conversion of the surface occurs, and that the addition of a surfactant improves CdS deposition and thus device performance; ii) XPS studies of polyethylene terephthalate (PET) candidate backsheet materials have shown that plasma exposure prior to oxide-barrier deposition results in the formation of low-molecular-weight fragments that result in the formation of a weak interfacial layer that fails during damp-heat exposure; iii) an empirical relation was derived for the source geometry that leads to optimal film-thickness uniformity in rotating-substrate physical-vapor deposition (PVD) systems; and iv) PVD flux-distribution calculations were performed to develop a novel method for combinatorial thin-film synthesis.

  8. Serum and skin surface antibody responses in merino sheep given three successive inoculations with Dermatophilus congolensis.

    Science.gov (United States)

    Sutherland, S S; Ellis, T M; Robertson, G M; Gregory, A R

    1987-11-01

    Three antigens prepared from different phases of the life cycle of Dermatophilus congolensis were used in an enzyme-linked immunosorbent assay to measure serum and skin surface antibody responses in sheep after a first, second and third inoculation with D. congolensis. After the first inoculation, a strong antibody response to the flagella, filament and soluble antigens was detected after 7-21 days in the sera from sheep that were regularly biopsied; the antibody response at the skin surface was detected 28-42 days after inoculation, when the lesions were resolving. Strong anamnestic responses were detected in the serum of sheep that were biopsied and some of the nonbiopsied sheep after the second and third inoculations, but the skin surface antibody response at these times was variable.

  9. High Quality Bioreplication of Intricate Nanostructures from a Fragile Gecko Skin Surface with Bactericidal Properties

    Science.gov (United States)

    Green, David William; Lee, Kenneth Ka-Ho; Watson, Jolanta Anna; Kim, Hyun-Yi; Yoon, Kyung-Sik; Kim, Eun-Jung; Lee, Jong-Min; Watson, Gregory Shaun; Jung, Han-Sung

    2017-01-01

    The external epithelial surfaces of plants and animals are frequently carpeted with small micro- and nanostructures, which broadens their adaptive capabilities in challenging physical habitats. Hairs and other shaped protuberances manage with excessive water, light contaminants, predators or parasites in innovative ways. We are interested in transferring these intricate architectures onto biomedical devices and daily-life surfaces. Such a project requires a very rapid and accurate small-scale fabrication process not involving lithography. In this study, we describe a simple benchtop biotemplating method using shed gecko lizard skin that generates duplicates that closely replicate the small nanotipped hairs (spinules) that cover the original skin. Synthetic replication of the spinule arrays in popular biomaterials closely matched the natural spinules in length. More significantly, the shape, curvature and nanotips of the synthetic arrays are virtually identical to the natural ones. Despite some small differences, the synthetic gecko skin surface resisted wetting and bacterial contamination at the same level as natural shed skin templates. Such synthetic gecko skin surfaces are excellent platforms to test for bacterial control in clinical settings. We envision testing the biocidal properties of the well-matched templates for fungal spores and viral resistance in biomedicine as well as co/multi-cultures.

  10. Insight into the immunobiology of human skin and functional specialization of skin dendritic cell subsets to innovate intradermal vaccination design.

    Science.gov (United States)

    Teunissen, M B M; Haniffa, M; Collin, M P

    2012-01-01

    Dendritic cells (DC) are the key initiators and regulators of any immune response which determine the outcome of CD4(+) and CD8(+) T-cell responses. Multiple distinct DC subsets can be distinguished by location, phenotype, and function in the homeostatic and inflamed human skin. The function of steady-state cutaneous DCs or recruited inflammatory DCs is influenced by the surrounding cellular and extracellular skin microenvironment. The skin is an attractive site for vaccination given the extended local network of DCs and the easy access to the skin-draining lymph nodes to generate effector T cells and immunoglobulin-producing B cells for long-term protective immunity. In the context of intradermal vaccination we describe in this review the skin-associated immune system, the characteristics of the different skin DC subsets, the mechanism of antigen uptake and presentation, and how the properties of DCs can be manipulated. This knowledge is critical for the development of intradermal vaccine strategies and supports the concept of intradermal vaccination as a superior route to the conventional intramuscular or subcutaneous methods.

  11. Under Persistent Assault: Understanding the Factors that Deteriorate Human Skin and Clinical Efficacy of Topical Antioxidants in Treating Aging Skin

    Directory of Open Access Journals (Sweden)

    Patricia K. Farris

    2015-11-01

    Full Text Available Recent studies contend that the skin is subject to far more damage than just ultraviolet (UV light, with infrared radiation and pollution now clearly demonstrated to degrade cutaneous tissue. While consumers continue to strive for new ways to augment the aesthetic appeal and improve the health of their skin, awareness regarding environmental insults and effective ways to protect the skin remains low. New advances in dermatologic science have exponentially increased the available information on the underlying mechanism of cutaneous damage and potential of topical antioxidants to treat aging skin. Combining antioxidants that can work through multiple pathways holds great potential for a cumulative and synergistic way to treat aging skin. Our goal is to provide a comprehensive review on environmental factors that damage human skin, discuss scientifically proven benefits of topical antioxidants, understand challenges of formulating and administering topical antioxidants, evaluate novel mechanisms of antioxidant activity, and suggest practical ways of integrating topical antioxidants with aesthetic procedures to complement clinical outcomes.

  12. The release of leukotriene B4 from human skin in response to substance P: evidence for the functional heterogeneity of human skin mast cells among individuals

    Science.gov (United States)

    Okabe, T; Hide, M; Koro, O; Nimi, N; Yamamoto, S

    2001-01-01

    Substance P is located in cutaneous nerve fibres and induces wheal and flare responses, accompanied by granulocyte infiltration, upon intradermal injection. Studies with animal skin and rat peritoneal mast cells have suggested that substance P induces the release of histamine and leukotriene B4 (LTB4), a potent chemoattractant for granulocytes, from skin mast cells. However, the release of LTB4 has not been detected from mast cells enzymatically isolated from human skin. In order to investigate the mechanism of granulocyte infiltration induced by substance P in human skin, we studied the release of LTB4 and histamine in response to substance P, and the effect of dexamethasone using human skin obtained from 22 nonallergic individuals. Histamine was released from all skin tissue samples in a dose-dependent manner. However, the amount of LTB4 release, both constitutive and inducible, was variable among skin preparations. Substance P induced a large release of LTB4 from the skin of eight donors (twice to six times that of the spontaneous release), but no or only negligible release from the skin of 14 donors. The amount of constitutive release of LTB4 correlated with the amount of tissue histamine. Dexamethasone selectively abolished the inducible release of LTB4, without an effect on histamine release and the constitutive release of LTB4. These results suggest that substance P induces the release of LTB4 in a certain population of human individuals by a glucocorticosteroid-dependent mechanism, and plays an important role in neurogenic inflammation with granulocyte infiltration. PMID:11359454

  13. RSDL decontamination of human skin contaminated with the nerve agent VX.

    Science.gov (United States)

    Thors, L; Lindberg, S; Johansson, S; Koch, B; Koch, M; Hägglund, L; Bucht, A

    2017-03-05

    also influenced the degradation rate since the degradation of VX was significantly faster when the NMR analysis was performed in the organic solvent acetonitrile compared to water. In conclusion, we have applied the in vitro flow-through diffusion cell for evaluation of skin decontamination procedures of human epidermis exposed to OPCs. It was demonstrated that early decontamination is crucial for efficient mitigation of epidermal penetration of VX and that almost complete removal of the nerve agent from the skin surface is possible. Our data also indicate that the pH of RSDL together with the solubility of OPC in RSDL are of primary importance for the decontamination efficacy. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Identification of Biomarkers of Human Skin Ageing in Both Genders. Wnt Signalling - A Label of Skin Ageing?

    Science.gov (United States)

    Zampeli, Vasiliki; Elewa, Rana Mohsen; Mlody, Barbara; Hossini, Amir M.; Hermes, Bjoern; Krause, Ulf; Knolle, Juergen; Abdallah, Marwa; Adjaye, James; Zouboulis, Christos C.

    2012-01-01

    The goal of our work has been to investigate the mechanisms of gender-independent human skin ageing and examine the hypothesis of skin being an adequate model of global ageing. For this purpose, whole genome gene profiling was employed in sun-protected skin obtained from European Caucasian young and elderly females (mean age 26.7±4 years [n1 = 7] and 70.75±3.3 years [n2 = 4], respectively) and males (mean age 25.8±5.2 years [n3 = 6] and 76±3.8 years [n4 = 7], respectively) using the Illumina array platform. Confirmation of gene regulation was performed by real-time RT-PCR and immunohistochemistry. 523 genes were significantly regulated in female skin and 401 genes in male skin for the chosen criteria. Of these, 183 genes exhibited increased and 340 decreased expression in females whereas 210 genes showed increased and 191 decreased expression in males with age. In total, 39 genes were common in the target lists of significant regulated genes in males and females. 35 of these genes showed increased (16) or decreased (19) expression independent of gender. Only 4 overlapping genes (OR52N2, F6FR1OP2, TUBAL3 and STK40) showed differential regulation with age. Interestingly, Wnt signalling pathway showed to be significantly downregulated in aged skin with decreased gene and protein expression for males and females, accordingly. In addition, several genes involved in central nervous system (CNS) ageing (f.i. APP, TAU) showed to be expressed in human skin and were significanlty regulated with age. In conclusion, our study provides biomarkers of endogenous human skin ageing in both genders and highlight the role of Wnt signalling in this process. Furthermore, our data give evidence that skin could be used as a good alternative to understand ageing of different tissues such as CNS. PMID:23226273

  15. Targeted sequencing of clade-specific markers from skin microbiomes for forensic human identification.

    Science.gov (United States)

    Schmedes, Sarah E; Woerner, August E; Novroski, Nicole M M; Wendt, Frank R; King, Jonathan L; Stephens, Kathryn M; Budowle, Bruce

    2018-01-01

    The human skin microbiome is comprised of diverse communities of bacterial, eukaryotic, and viral taxa and contributes millions of additional genes to the repertoire of human genes, affecting human metabolism and immune response. Numerous genetic and environmental factors influence the microbiome composition and as such contribute to individual-specific microbial signatures which may be exploited for forensic applications. Previous studies have demonstrated the potential to associate skin microbial profiles collected from touched items to their individual owner, mainly using unsupervised methods from samples collected over short time intervals. Those studies utilize either targeted 16S rRNA or shotgun metagenomic sequencing to characterize skin microbiomes; however, these approaches have limited species and strain resolution and susceptibility to stochastic effects, respectively. Clade-specific markers from the skin microbiome, using supervised learning, can predict individual identity using skin microbiomes from their respective donors with high accuracy. In this study the hidSkinPlex is presented, a novel targeted sequencing method using skin microbiome markers developed for human identification. The hidSkinPlex (comprised of 286 bacterial (and phage) family-, genus-, species-, and subspecies-level markers), initially was evaluated on three bacterial control samples represented in the panel (i.e., Propionibacterium acnes, Propionibacterium granulosum, and Rothia dentocariosa) to assess the performance of the multiplex. The hidSkinPlex was further evaluated for prediction purposes. The hidSkinPlex markers were used to attribute skin microbiomes collected from eight individuals from three body sites (i.e., foot (Fb), hand (Hp) and manubrium (Mb)) to their host donor. Supervised learning, specifically regularized multinomial logistic regression and 1-nearest-neighbor classification were used to classify skin microbiomes to their hosts with up to 92% (Fb), 96% (Mb

  16. The cutaneous ecosystem: the roles of the skin microbiome in health and its association with inflammatory skin conditions in humans and animals.

    Science.gov (United States)

    Rodrigues Hoffmann, Aline

    2017-02-01

    Inhabiting a sterile world is no longer an acceptable or desirable concept. Recent studies developed in the microbiome field have unveiled complex microbial populations inhabiting the skin, digestive, respiratory and reproductive tracts. Microbiome studies have opened new venues to explore the human and animal second genome, its functions and its importance in maintaining health. The composition of the skin microbiome varies across different body sites and across individuals, being influenced by different host habits, including for instance age, sex, diet, hygiene and lifestyle. Exposure to a diverse skin microbiome is now considered to be a key component in immune regulation, and imbalances in these microbial populations are being associated with human and animal skin inflammatory disorders. We have learned that in several skin conditions, there is a significant alteration in the diversity and composition of the microbiota colonizing the skin. For instance, in human and animal patients with atopic dermatitis, dysbiosis of the skin microbiota results in lower diversity of microbial populations. Whether these altered microbial populations are the cause or the effect of inflammatory skin conditions seen in humans and animals are still under investigation, but there is no doubt that the microbiome has an important role in maintaining skin health. This review focuses on the most current studies describing the skin microbiome in humans and animals, its role in modulating the immune system, and its association with human and animal skin diseases. © 2017 ESVD and ACVD.

  17. Surface Dielectric Barrier Discharge Jet for Skin Disinfection

    Science.gov (United States)

    Creyghton, Yves; Meijer, Rogier; Verweij, Paul; van der Zanden, Frank; Leenders, Paul

    A consortium consisting of the research institute TNO, the medical ­university and hospital St Radboud and two industrial enterprises is working on a non-thermal plasma treatment method for hand disinfection. The group is seeking for cooperation, in particular in the field of validation methods and potential ­standardization for plasma based disinfection procedures. The present paper describes technical progress in plasma source development together with initial microbiological data. Particular properties of the sheet shaped plasma volume are the possibility of treating large irregular surfaces in a short period of time, effective plasma produced species transfer to the surface together with high controllability of the nature of plasma species by means of temperature conditioning.

  18. A micromechanical comparison of human and porcine skin before and after preservation by freezing for medical device development

    Science.gov (United States)

    Ranamukhaarachchi, S. A.; Lehnert, S.; Ranamukhaarachchi, S. L.; Sprenger, L.; Schneider, T.; Mansoor, I.; Rai, K.; Häfeli, U. O.; Stoeber, B.

    2016-08-01

    Collecting human skin samples for medical research, including developing microneedle-based medical devices, is challenging and time-consuming. Researchers rely on human skin substitutes and skin preservation techniques, such as freezing, to overcome the lack of skin availability. Porcine skin is considered the best substitute to human skin, but their mechanical resemblance has not been fully validated. We provide a direct mechanical comparison between human and porcine skin samples using a conventional mechano-analytical technique (microindentation) and a medical application (microneedle insertion), at 35% and 100% relative humidity. Human and porcine skin samples were tested immediately after surgical excision from subjects, and after one freeze-thaw cycle at -80 °C to assess the impact of freezing on their mechanical properties. The mechanical properties of fresh human and porcine skin (especially of the stratum corneum) were found to be different for bulk measurements using microindentation; and both types of skin were mechanically affected by freezing. Localized in-plane mechanical properties of skin during microneedle insertion appeared to be more comparable between human and porcine skin samples than their bulk out-of-plane mechanical properties. The results from this study serve as a reference for future mechanical tests conducted with frozen human skin and/or porcine skin as a human skin substitute.

  19. Surface determination of 3D confocal Raman microscopy imaging of the skin

    Science.gov (United States)

    Schleusener, J.; Carrer, V.; Patzelt, A.; Lademann, J.; Darvin, M. E.

    2017-12-01

    A surface determination method for the application of 3D confocal Raman microscopy on inhomogeneous skin sections has been presented, which is based on depth profiles of the keratin contribution of the acquired Raman spectra. The method was compared to two similar auto-focusing methods that are based on the intensity of the reflected excitation light and Raman spectra, respectively. The measurements were performed on hair follicles containing skin sections of porcine ears ex vivo. The surface determination on such samples is especially challenging due to their different molecular composition and surface inhomogeneity. An advantage of this method is molecular sensitivity, whereby only the surface of the sample will be detected and not the substrate of the microscope slide, in the case of disruptions during the processing of samples. A disadvantage of the method is the increased overall acquisition time if only the surface spectra are to be applied for 2D mapping.

  20. Effects of single application of a moisturizer: evaporation of emulsion water, skin surface temperature, electrical conductance, electrical capacitance, and skin surface (emulsion) lipids.

    Science.gov (United States)

    Blichmann, C W; Serup, J; Winther, A

    1989-01-01

    Effects of single application of an oil in water emulsion were studied on the forearm skin of 12 healthy volunteers. Five different non-invasive methods were used. Values were followed for 360 min after application of the emulsion, with the contralateral forearm as untreated control. The evaporation of emulsion water from the skin surface immediately rose to high values, but within 15 min returned to the original level. A parallel initial increase in conductance was observed; however, this was followed by a slightly increased level throughout the 360 min study. Electrical capacitance was also slightly increased throughout the study. Skin surface lipids, dominated by emulsion lipids, were increased, with high values for at least 120 min, followed by a gradual decline toward normal. Single application of emulsion is characterized by an initial evaporation phase, with evaporation of emulsion water, which lasts less than 15 min, followed by a lipidization phase, which lasts at least 360 min, dominated by the oil-constituent of the emulsion undergoing epidermal absorption. During the lipidization phase, epidermal hydration parameters are slightly but consistently improved.

  1. Machine Learning Approaches for Predicting Human Skin Sensitization Hazard

    Science.gov (United States)

    One of ICCVAM’s top priorities is the development and evaluation of non-animal approaches to identify potential skin sensitizers. The complexity of biological events necessary for a substance to elicit a skin sensitization reaction suggests that no single in chemico, in vit...

  2. Background free imaging of upconversion nanoparticle distribution in human skin

    NARCIS (Netherlands)

    Song, Zhen; Anissimov, Yuri G.; Zhao, Jiangbo; Nechaev, Andrei V.; Nadort, Annemarie; Jin, Dayong; Prow, Tarl W.; Roberts, Michael S.; Zvyagin, Andrei V.

    2013-01-01

    Widespread applications of nanotechnology materials have raised safety concerns due to their possible penetration through skin and concomitant uptake in the organism. This calls for systematic study of nanoparticle transport kinetics in skin, where high-resolution optical imaging approaches are

  3. A gecko skin micro/nano structure - A low adhesion, superhydrophobic, anti-wetting, self-cleaning, biocompatible, antibacterial surface.

    Science.gov (United States)

    Watson, Gregory S; Green, David W; Schwarzkopf, Lin; Li, Xin; Cribb, Bronwen W; Myhra, Sverre; Watson, Jolanta A

    2015-07-01

    Geckos, and specifically their feet, have attracted significant attention in recent times with the focus centred around their remarkable adhesional properties. Little attention however has been dedicated to the other remaining regions of the lizard body. In this paper we present preliminary investigations into a number of notable interfacial properties of the gecko skin focusing on solid and aqueous interactions. We show that the skin of the box-patterned gecko (Lucasium sp.) consists of dome shaped scales arranged in a hexagonal patterning. The scales comprise of spinules (hairs), from several hundred nanometres to several microns in length, with a sub-micron spacing and a small radius of curvature typically from 10 to 20 nm. This micro and nano structure of the skin exhibited ultralow adhesion with contaminating particles. The topography also provides a superhydrophobic, anti-wetting barrier which can self clean by the action of low velocity rolling or impacting droplets of various size ranges from microns to several millimetres. Water droplets which are sufficiently small (10-100 μm) can easily access valleys between the scales for efficient self-cleaning and due to their dimensions can self-propel off the surface enhancing their mobility and cleaning effect. In addition, we demonstrate that the gecko skin has an antibacterial action where Gram-negative bacteria (Porphyromonas gingivalis) are killed when exposed to the surface however eukaryotic cell compatibility (with human stem cells) is demonstrated. The multifunctional features of the gecko skin provide a potential natural template for man-made applications where specific control of liquid, solid and biological contacts is required. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  4. Prolonged Survival of Pig Skin on Baboons After Administration of Pig Cells Expressing Human CD47.

    Science.gov (United States)

    Tena, Aseda A; Sachs, David H; Mallard, Christopher; Yang, Yong-Guang; Tasaki, Masayuki; Farkash, Evan; Rosales, Ivy A; Colvin, Robert B; Leonard, David A; Hawley, Robert J

    2017-02-01

    Successful xenotransplantation will likely depend, in part, on the induction of immunological tolerance, because the high levels of immunosuppression otherwise required would likely have unacceptable side effects. Rapid clearance of administered porcine hematopoietic stem cells by primate macrophages has hampered previous attempts to induce tolerance through mixed hematopoietic chimerism across a pig-to-primate barrier. Phagocytosis is normally inhibited by binding of cell surface protein CD47 to macrophage signal regulatory protein α receptors. However, pig CD47 has previously been shown to be ineffective in transducing signals through primate signal regulatory protein α. Mobilized peripheral blood hematopoietic cells from transgenic swine expressing high or low levels of human CD47 were infused into conditioned baboons at 3 time points over a 9-week period. Xenogeneic peripheral blood chimerism was assessed after each infusion. Split thickness skin grafts from the hematopoietic cell donor swine were placed on recipients 5 weeks after the last cell infusion and 7 weeks after the discontinuation of all immunosuppression to test immune response. The level and duration of transient chimerism were substantially greater in baboons receiving hematopoietic cells from a pig expressing high levels of human CD47. Skin graft survival on high CD47 recipients was prolonged as well, in 1 case showing no signs of rejection at least 53 days after placement. Prolongation of transient porcine chimerism via transgenic expression of human CD47 in a primate model is associated with an immune modulating effect, leading to markedly prolonged survival of donor swine skin xenografts that may be applicable to clinical solid organ xenotransplantation.

  5. Micropatch-arrayed pads for non-invasive spatial and temporal profiling of topical drugs on skin surface.

    Science.gov (United States)

    Dutkiewicz, Ewelina P; Chiu, Hsien-Yi; Urban, Pawel L

    2015-11-01

    Micropatch-arrayed pads (MAPAs) are presented as a facile and sensitive sampling method for spatial profiling of topical agents adsorbed on the surface of skin. MAPAs are 28 × 28 mm sized pieces of polytetrafluoroethylene containing plurality of cavities filled with agarose hydrogel. They are affixed onto skin for 10 min with the purpose to collect drugs applied topically. Polar compounds are absorbed by the hydrogel micropatches. The probes are subsequently scanned by an automated nanospray desorption electrospray ionization mass spectrometry system operated in the tapping dual-polarity mode. When the liquid junction gets into contact with every micropatch, polar compounds absorbed in the hydrogel matrix are desorbed and transferred to the ion source. A 3D-printed interface prevents evaporation of hydrogel micropatches assuring good reproducibility and sensitivity. MAPAs have been applied to follow dispersion of topical drugs applied to human skin in vivo and to porcine skin ex vivo, in the form of self-adhesive patches. Spatiotemporal characteristics of the drug dispersion process have been revealed using this non-invasive test. Differences between drug dispersion in vivo and ex vivo could be observed. We envision that MAPAs can be used to investigate spatiotemporal kinetics of various topical agents utilized in medical treatment. Copyright © 2015 John Wiley & Sons, Ltd.

  6. In vivo non-invasive multiphoton tomography of human skin

    Science.gov (United States)

    König, Karsten; Riemann, Iris; Ehlers, Alexander; Le Harzic, Ronan

    2005-10-01

    High resolution non-invasive 3D imaging devices are required to detect pathogenic microorganisms such as Anthrax spores, bacteria, viruses, fungi and chemical agents entering biological tissues such as the epidermis. Due to the low light penetration depth and the biodamage potential, ultraviolet light sources can not be employed to realize intratissue imaging of bio- and chemohazards. We report on the novel near infrared laser technology multiphoton tomography and the high resolution 4D imaging tool DermaInspect for non-invasive detection of intratissue agents and their influence on cellular metabolism based on multiphoton autofluorescence imaging (MAI) and second harmonic generation (SHG). Femtosecond laser pulses in the spectral range of 750 nm to 850 nm have been used to image in vivo human skin with subcellular spatial and picosecond temporal resolution. The non-linear induced autofluorescence of both, skin tissues and microorganisms, originates mainly from naturally endogenous fluorophores/protein structures like NAD(P)H, flavins, keratin, collagen, elastin, porphyrins and melanin. Bacteria emit in the blue/green spectral range due to NAD(P)H and flavoproteins and, in certain cases, in the red spectral range due to the biosynthesis of Zn-porphyrins, coproporphyrin and protoporphyrin. Collagen and exogenous non-centrosymmetric molecules can be detected by SHG signals. The system DermaInspect consists of a wavelength-tunable compact 80/90 MHz Ti:sapphire laser, a scan module with galvo scan mirrors, piezo-driven objective, fast photon detector and time-resolved single photon counting unit. It can be used to perform optical sectioning and 3D autofluorescence lifetime imaging (τ-mapping) with 1 μm spatial resolution and 270 ps temporal resolution. The parameter fluorescence lifetime depends on the type of fluorophore and its microenvironment and can be used to distinguish bio- and chemohazards from cellular background and to gain information for pathogen

  7. Measurement of Turbulent Skin Friction Drag Coefficients Produced by Distributed Surface Roughness of Pristine Marine Coatings

    DEFF Research Database (Denmark)

    Zafiryadis, Frederik; Meyer, Knud Erik; Gökhan Ergin, F.

    Skin friction drag coefficients are determined for marine antifouling coatings in pristine condition by use of Constant Temperature Anemometry (CTA) with uni-directionalhot-wires. Mean flow behaviour for varying surface roughness is analysed in zero pressure gradient, flat plate, turbulentboundary...... drag coefficients as well as roughness Reynolds numbers for the various marine coatings across the range of Rex by fitting of the van Driest profile. The results demonstrate sound agreement with the present ITTC method for determining skin friction coefficients for practically smooth surfaces at low...... layers for Reynolds numbers from Rex =1:91x105 to Rex = 9:54x105. The measurements were conducted at the Technical University of Denmark in a closed-loop wind tunnel redesigned for investigations as this. Ensemble averages of the boundary layer velocity profiles allowed for determination of skin friction...

  8. Tissue responses to fractional transient heating with sinusoidal heat flux condition on skin surface.

    Science.gov (United States)

    Ezzat, Magdy A; El-Bary, Alaa A; Al-Sowayan, Noorah S

    2016-10-01

    A fractional model of Bioheat equation for describing quantitatively the thermal responses of skin tissue under sinusoidal heat flux conditions on skin surface is given. Laplace transform technique is used to obtain the solution in a closed form. The resulting formulation is applied to one-dimensional application to investigate the temperature distribution in skin with instantaneous surface heating for different cases. According to the numerical results and its graphs, conclusion about the fractional bioheat transfer equation has been constructed. Sensitivity analysis is performed to explore the thermal effects of various control parameters on tissue temperature. The comparisons are made with the results obtained in the case of the absence of time-fractional order. © 2016 Japanese Society of Animal Science. © 2016 Japanese Society of Animal Science.

  9. Cutaneous in vivo metabolism of topical lidocaine formulation in human skin

    DEFF Research Database (Denmark)

    Rolsted, K; Benfeldt, E; Kissmeyer, A-M

    2009-01-01

    Little is known about the metabolising capacity of the human skin in relation to topically applied drugs and formulations. We chose lidocaine as a model compound since the metabolic pathways are well known from studies concerning hepatic metabolism following systemic drug administration. However......, the enzymes involved are also expressed in the skin. Hence, the aim of the current study was to investigate the extent of the cutaneous in vivo metabolism of topically applied lidocaine in human volunteers. A dose of 5 mg/cm(2) of Xylocaine(R) (5% lidocaine) ointment was applied onto the buttock skin...... of the volunteers. After 2 h, residual formulation was removed, and two 4-mm punch biopsies were taken from each volunteer. The quantity of lidocaine extracted from the skin samples (epidermis + dermis) was 109 +/- 43 ng/mm(2) skin. One metabolite (monoethylglycine xylidide, MEGX) was detected in skin from 7...

  10. Photoprotection by pistachio bioactives in a 3-dimensional human skin equivalent tissue model.

    Science.gov (United States)

    Chen, C-Y Oliver; Smith, Avi; Liu, Yuntao; Du, Peng; Blumberg, Jeffrey B; Garlick, Jonathan

    2017-09-01

    Reactive oxygen species (ROS) generated during ultraviolet (UV) light exposure can induce skin damage and aging. Antioxidants can provide protection against oxidative injury to skin via "quenching" ROS. Using a validated 3-dimensional (3D) human skin equivalent (HSE) tissue model that closely mimics human skin, we examined whether pistachio antioxidants could protect HSE against UVA-induced damage. Lutein and γ-tocopherol are the predominant lipophilic antioxidants in pistachios; treatment with these compounds prior to UVA exposure protected against morphological changes to the epithelial and connective tissue compartments of HSE. Pistachio antioxidants preserved overall skin thickness and organization, as well as fibroblast morphology, in HSE exposed to UVA irradiation. However, this protection was not substantiated by the analysis of the proliferation of keratinocytes and apoptosis of fibroblasts. Additional studies are warranted to elucidate the basis of these discordant results and extend research into the potential role of pistachio bioactives promoting skin health.

  11. Cavitation-enhanced delivery of insulin in agar and porcine models of human skin.

    Science.gov (United States)

    Feiszthuber, Helga; Bhatnagar, Sunali; Gyöngy, Miklós; Coussios, Constantin-C

    2015-03-21

    Ultrasound-assisted transdermal insulin delivery offers a less painful and less invasive alternative to subcutaneous insulin injections. However, ultrasound-based drug delivery, otherwise known as sonophoresis, is a highly variable phenomenon, in part dependent on cavitation. The aim of the current work is to investigate the role of cavitation in transdermal insulin delivery. Fluorescently stained, soluble Actrapid insulin was placed on the surface of human skin-mimicking materials subjected to 265 kHz, 10% duty cycle focused ultrasound. A confocally and coaxially aligned 5 MHz broadband ultrasound transducer was used to detect cavitation. Two different skin models were used. The first model, 3% agar hydrogel, was insonated with a range of pressures (0.25-1.40 MPa peak rarefactional focal pressure-PRFP), with and without cavitation nuclei embedded within the agar at a concentration of 0.05% w/v. The second, porcine skin was insonated at 1.00 and 1.40 MPa PRFP. In both models, fluorescence measurements were used to determine penetration depth and concentration of delivered insulin. Results show that in agar gel, both insulin penetration depth and concentration only increased significantly in the presence of inertial cavitation, with up to a 40% enhancement. In porcine skin the amount of fluorescent insulin was higher in the epidermis of those samples that were exposed to ultrasound compared to the control samples, but there was no significant increase in penetration distance. The results underline the importance of instigating and monitoring inertial cavitation during transdermal insulin delivery.

  12. Cavitation-enhanced delivery of insulin in agar and porcine models of human skin

    Science.gov (United States)

    Feiszthuber, Helga; Bhatnagar, Sunali; Gyöngy, Miklós; Coussios, Constantin-C.

    2015-03-01

    Ultrasound-assisted transdermal insulin delivery offers a less painful and less invasive alternative to subcutaneous insulin injections. However, ultrasound-based drug delivery, otherwise known as sonophoresis, is a highly variable phenomenon, in part dependent on cavitation. The aim of the current work is to investigate the role of cavitation in transdermal insulin delivery. Fluorescently stained, soluble Actrapid insulin was placed on the surface of human skin-mimicking materials subjected to 265 kHz, 10% duty cycle focused ultrasound. A confocally and coaxially aligned 5 MHz broadband ultrasound transducer was used to detect cavitation. Two different skin models were used. The first model, 3% agar hydrogel, was insonated with a range of pressures (0.25-1.40 MPa peak rarefactional focal pressure—PRFP), with and without cavitation nuclei embedded within the agar at a concentration of 0.05% w/v. The second, porcine skin was insonated at 1.00 and 1.40 MPa PRFP. In both models, fluorescence measurements were used to determine penetration depth and concentration of delivered insulin. Results show that in agar gel, both insulin penetration depth and concentration only increased significantly in the presence of inertial cavitation, with up to a 40% enhancement. In porcine skin the amount of fluorescent insulin was higher in the epidermis of those samples that were exposed to ultrasound compared to the control samples, but there was no significant increase in penetration distance. The results underline the importance of instigating and monitoring inertial cavitation during transdermal insulin delivery.

  13. Pattern of skin surface lipids in some South-Western Nigerians with ...

    African Journals Online (AJOL)

    Unanswered questions still exist regarding pathophysiology of acne vulgaris generally and particularly in this environment. Methods: Skin surface lipid (SSL) samples were collected by the heptane sponge technique from faces of 20 Nigerians with facial acne vulgaris and 25 controls. The subjects were classified into mild ...

  14. Pattern of skin surface lipids in some South-Western Nigerians with ...

    African Journals Online (AJOL)

    Nigeria. Summary. Unanswered questions still exist regarding pathophysi- ology of acne vulgaris generally and particularly in this environment. Methods: Skin surface lipid (SSL) samples were collected by the heptane sponge technique from faces of 20 Nigerians with facial acne vulgaris and 25 controls. The subjects were.

  15. Scratch resistance of the ventral skin surface in four snake species (Squamata, Serpentes).

    Science.gov (United States)

    Klein, Marie-Christin G; Gorb, Stanislav N

    2016-04-01

    Snakes are limbless tetrapods highly specialized for sliding locomotion on various substrates. Their skin is constantly exposed to high friction forces, which promotes abrasion. Snake skin has material and surface specializations, presumably optimized for friction and abrasion resistance. We found that different snake species living in different habitats have different abrasion patterns and hypothesized that this correlates with specific epidermal architecture and surface topography. To test this hypothesis artificial scratches, under controlled load conditions, were created on the ventral skin material (epidermis) of four snake species adapted to different habitats: Lampropeltis getula californiae (stony and sandy soil substrates), Epicrates cenchria cenchria (trees, soil and water), Morelia viridis (trees), and Gongylophis colubrinus (burrowing in sand). Abrasion appearance on the skin surface was examined using scanning electron microscopy and white light interferometry. The material failure was different between the species, which we attribute to differences in the epidermis' response to the same abrasive challenge. We also discuss abrasion resistance mechanisms and the correlation with the different ultrastructure and surface microstructure. Copyright © 2016. Published by Elsevier GmbH.

  16. First donation of human skin obtained from corpse; Primera donacion de piel humana obtenida de cadaver

    Energy Technology Data Exchange (ETDEWEB)

    Reyes F, M.L.; Luna Z, D. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)

    2007-07-01

    The first donation of human skin coming from a cadaverous donor was obtained in the State of Mexico. The skin was obtained of a 34 year-old multi organic donor, the extraction of the same was carried out in an operating theatre by medical personnel, supported by personal of the Radio sterilized Tissue Bank (BTR) of the ININ. The skin was transported to the BTR for it processing. (Author)

  17. Nicotinic acid receptor abnormalities in human skin cancer: implications for a role in epidermal differentiation.

    Directory of Open Access Journals (Sweden)

    Yira Bermudez

    Full Text Available Chronic UV skin exposure leads to epidermal differentiation defects in humans that can be largely restored by pharmacological doses of nicotinic acid. Nicotinic acid has been identified as a ligand for the human G-protein-coupled receptors GPR109A and GPR109B that signal through G(i-mediated inhibition of adenylyl cyclase. We have examined the expression, cellular distribution, and functionality of GPR109A/B in human skin and skin derived epidermal cells.Nicotinic acid increases epidermal differentiation in photodamaged human skin as judged by the terminal differentiation markers caspase 14 and filaggrin. Both GPR109A and GPR109B genes are transcribed in human skin and in epidermal keratinocytes, but expression in dermal fibroblasts is below limits of detection. Receptor transcripts are greatly over-expressed in squamous cell cancers. Receptor protein in normal skin is prominent from the basal through granular layers of the epidermis, with cellular localization more dispersive in the basal layer but predominantly localized at the plasma membrane in more differentiated epidermal layers. In normal human primary and immortalized keratinocytes, nicotinic acid receptors show plasma membrane localization and functional G(i-mediated signaling. In contrast, in a squamous cell carcinoma derived cell line, receptor protein shows a more diffuse cellular localization and the receptors are nearly non-functional.The results of these studies justify future genetic and pharmacological intervention studies to define possible specific role(s of nicotinic acid receptors in human skin homeostasis.

  18. “Review on Human Face Detection based on Skin Color and Edge Information”

    OpenAIRE

    Divyesh S. Gondaliya; Pratik P. Kamothi; Vicky N. Fudnawala; Kevin P. Patel; Hiren S. Patel; Sapan Naik

    2015-01-01

    Human face detection system is gradually used for the tracking a human face. Face detection system is mainly used in face reorganization system for detecting human face. Here in this review paper we have describe how face detection system works and where it is useful in real world environment. We have describes different technique like template matching, skin color and edge information based on face detection from skin region, symmetry based face detection and etc.

  19. Spatially Resolved Two-Color Diffusion Measurements in Human Skin Applied to Transdermal Liposome Penetration

    DEFF Research Database (Denmark)

    Brewer, Jonathan; Bloksgaard, Maria; Kubiak, Jakub

    2013-01-01

    of the liposome composition (phospholipids or transfersomes), our results show a clear lack of cross-correlation below the skin surface, indicating that the penetration of intact liposomes is highly compromised by the skin barrier.Journal of Investigative Dermatology advance online publication, 6 December 2012...

  20. [Normal and abnormal human skin colour: from research to aesthetics].

    Science.gov (United States)

    Ortonne, J-P

    2008-02-01

    Skin color is controlled by pigmentary genes that regulate constitutive skin pigmentation and by environmental factors, the most obvious of them being solar U.V. At this time, more than 125 distinct pigmentary genes are known. They affect embryogenesis and survival of the melanocyte system, mélanosome biogenesis, melanogenesis, mélanosome transport and transfer, eumelanins/pheomelanins ratio and epidermal mélanosome turn-over and elimination. The pigmentary disorders of the skin are common and represent an important part of dermatologist activity. They concern at the same time the general dermatology and the aesthetic dermatology.

  1. [Normal and abnormal human skin color: from research to esthetics].

    Science.gov (United States)

    Ortonne, J-P

    2009-10-01

    Skin color is controlled by pigmentary genes that regulate constitutive skin pigmentation and by environmental factors, the most obvious of them being solar U.V. At this time, more than 130 distinct pigmentary genes are known. They affect embryogenesis and survival of the melanocyte system, mélanosome biogenesis, melanogenesis, mélanosome transport and transfer, eumelanins/pheomelanins ratio and epidermal mélanosome turn-over and elimination. The pigmentary disorders of the skin are common and represent an important part of dermatologist activity. They concern at the same time the general dermatology and the aesthetic dermatology.

  2. In vitro study of ethosome penetration in human skin and hypertrophic scar tissue.

    Science.gov (United States)

    Zhang, Zhen; Wo, Yan; Zhang, Yixin; Wang, Danru; He, Rong; Chen, Huijin; Cui, Daxiang

    2012-08-01

    The purpose of this study is to characterize a novel transdermal delivery carrier, ethosomes containing 5-fluorouracil. The delivery of drugs from ethosomes in human hypertrophic scar (HS) and the mechanisms of action of ethosomes in human HS were investigated. Percutaneous ethosome permeation was evaluated in vitro in human HS and skin using a Franz's cell. The amount of 5-fluorouracil that permeated HS and skin after 24 hours was most abundant in ethosomes via HS (E-Scar), followed by hydroethanolic solution via HS (H-Scar), ethosomes via skin (E-Skin), and hydroethanolic solution via skin (H-Skin). The penetration of ethosomes in HS and skin was analyzed by ethosomes fluorescently labeled with rhodamine 6GO using confocal laser scanning microscopy. The fluorescence intensity after application for 24 hours was highest in E-Scar, followed by E-Skin, H-Scar, and H-Skin, which indicates the penetration of ethosomes in HS was greatest. In conclusion, we consider that ethosomes are a highly efficient carrier in HS. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Dermal absorption behavior of fluorescent molecules in nanoparticles on human and porcine skin models.

    Science.gov (United States)

    Debotton, Nir; Badihi, Amit; Robinpour, Mano; Enk, Claes D; Benita, Simon

    2017-05-30

    The percutaneous passage of poorly skin absorbed molecules can be improved using nanocarriers, particularly biodegradable polymeric nanospheres (NSs) or nanocapsules (NCs). However, penetration of the encapsulated molecules may be affected by other factors than the nanocarrier properties. To gain insight information on the skin absorption of two fluorescent cargos, DiIC18(5) and coumarin-6 were incorporated in NSs or NCs and topically applied on various human and porcine skin samples. 3D imaging techniques suggest that NSs and NCs enhanced deep dermal penetration of both probes similarly, when applied on excised human skin irrespective of the nature of the cargo. However, when ex vivo pig skin was utilized, the cutaneous absorption of DiIC18(5) was more pronounced by means of PLGA NCs than NSs. In contrast, PLGA NSs noticeably improved the porcine skin penetration of coumarin-6, as compared to the NCs. Furthermore, the porcine skin results were reproducible when triplicated whereas from various human skin samples, as expected, the results were not sufficiently reproducible and large deviations were observed. The overall findings from this comprehensive comparison emphasize the potential of PLGA NCs or NSs to promote cutaneous bioavailability of encapsulated drugs, exhibiting different physicochemical properties but depending on the nature of the skin. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Histamine is not released in acute thermal injury in human skin in vivo: a microdialysis study

    DEFF Research Database (Denmark)

    Petersen, Lars J; Pedersen, Juri L; Skov, Per S

    2009-01-01

    BACKGROUND: Animal models have shown histamine to be released from the skin during the acute phase of a burn injury. The role of histamine during the early phase of thermal injuries in humans remains unclear. PURPOSE: The objectives of this trial were to study histamine release in human skin during...... the acute phase of a standardized thermal injury in healthy volunteers. METHODS: Histamine concentrations in human skin were measured by skin microdialysis technique. Microdialysis fibers were inserted into the dermis in the lower leg in male healthy volunteers. A standardized superficial thermal injury...... was elicited by a heating thermode (49 degrees C) applied to the skin for 5 min. Histamine in dialysate was analyzed for up to 2 h after the injury using two different analytical methods. RESULTS: Spectrofluorometric assay of histamine showed no histamine release in separate studies using 2-min samples over 20...

  5. Visualization studies of human skin in vitro/in vivo under the influence of an electrical field

    NARCIS (Netherlands)

    Fatouros, N.E.; Groenink, H.W.M.; Graaff, de A.M.; Aelst, van A.C.; Koerten, H.K.; Bouwstra, J.A.

    2006-01-01

    The aim of this study was to investigate the local changes in the ultrastructure of human skin after iontophoresis, using cryo-scanning, transmission and freeze fracture electron microscopy in human skin in vitro and in vivo. Human dermatomed skin was subjected to passive diffusion for 6 hours

  6. Hollow agarose microneedle with silver coating for intradermal surface-enhanced Raman measurements: a skin-mimicking phantom study

    Science.gov (United States)

    Yuen, Clement; Liu, Quan

    2015-06-01

    Human intradermal components contain important clinical information beneficial to the field of immunology and disease diagnosis. Although microneedles have shown great potential to act as probes to break the human skin barrier for the minimally invasive measurement of intradermal components, metal microneedles that include stainless steel could cause the following problems: (1) sharp waste production, and (2) contamination due to reuse of microneedles especially in developing regions. In this study, we fabricate agarose microneedles coated with a layer of silver (Ag) and demonstrate their use as a probe for the realization of intradermal surface-enhanced Raman scattering measurements in a set of skin-mimicking phantoms. The Ag-coated agarose microneedle quantifies a range of glucose concentrations from 5 to 150 mM inside the skin phantoms with a root-mean-square error of 5.1 mM within 10 s. The needle is found enlarged by 53.9% after another 6 min inside the phantom. The shape-changing capability of this agarose microneedle ensures that the reuse of these microneedles is impossible, thus avoiding sharp waste production and preventing needle contamination, which shows the great potential for safe and effective needle-based measurements.

  7. Effect of terbutaline and bambuterol on immediate-type allergic skin responses and mediator release in human skin.

    Science.gov (United States)

    Petersen, L J; Skov, P S

    2003-09-01

    Beta-2 agonists are potent inhibitors of mast cell degranulation in vitro. Intradermally injected they also inhibit mast cell activation in human skin in vivo. To what extent orally administered beta(2)-agonists inhibit mast cell degranulation and allergic skin responses in vivo in daily recommended doses remains unclear. The main purpose was to study the effects of oral administered terbutaline and bambuterol on allergen- and codeine-induced histamine release and skin responses in intact human skin in vivo. In addition, control studies were carried out with intradermally injected terbutaline. Ten allergic subjects were randomized to receive bambuterol (10 mg tablets twice daily), terbutaline (7.5 mg controlled release tablets twice daily) and corresponding placebo for 5 days with a washout phase of 3 days between treatments in a double-blind, double-dummy, cross-over trial. The patients were studied at the fifth day of each regimen, i.e. at day 5, 13, and 21. Allergen- and codeine-induced histamine release was measured by microdialysis technique. Wheal and flare reactions to allergen, codeine, and histamine were measured planimetrically. Measurements were performed in the morning on day 5 on each regimen before medication and for additional 5 h after administration of the morning dose. In a separate series of experiments in another 10 allergic patients, 1-1,000 nM (0.05-50 pmoles) of terbutaline was injected intradermally for measurement of histamine release, prostaglandin D2 (PGD2) synthesis and skin responses. Neither orally administered terbutaline nor bambuterol significantly reduced allergen- or codeine-induced histamine release. Flare reactions to allergen, codeine and histamine remained unaffected which was also the case for the majority of the wheal reactions. In comparison, intradermally injected terbutaline significantly reduced allergen-induced histamine release, PGD(2) synthesis, and skin reactions. Codeine-induced histamine release remained unaffected

  8. Characterizing human skin blood flow regulation in response to different local skin temperature perturbations

    NARCIS (Netherlands)

    Wu, Y.; Nieuwenhoff, M.D.; Huygen, Frank J.P.M.; van der Helm, F. C.T.; Niehof, S.P.; Schouten, A. C.

    2017-01-01

    Small nerve fibers regulate local skin blood flow in response to local thermal perturbations. Small nerve fiber function is difficult to assess with classical neurophysiological tests. In this study, a vasomotor response model in combination with a heating protocol was developed to quantitatively

  9. Characterizing human skin blood flow regulation in response to different local skin temperature perturbations

    NARCIS (Netherlands)

    Wu, Y.; Nieuwenhoff, M.D.; Huygen, F.J.P.M.; van der Helm, F.C.T.; Niehof, S.P.; Schouten, A.C.

    2017-01-01

    Small nerve fibers regulate local skin blood flow in response to local thermal perturbations. Small nerve fiber function is difficult to assess with classical neurophysiological tests. In this study, a vasomotor response model in combination with a heating protocol was developed to quantitatively

  10. Characterizing human skin blood flow regulation in response to different local skin temperature perturbations

    NARCIS (Netherlands)

    Wu, Y.; M.D. Nieuwenhoff (Mariska D.); F.J.P.M. Huygen (Frank); F.C.T. van der Helm (Frans C.); S.P. Niehof (Sjoerd); A.C. Schouten (A.)

    2017-01-01

    textabstractSmall nerve fibers regulate local skin blood flow in response to local thermal perturbations. Small nerve fiber function is difficult to assess with classical neurophysiological tests. In this study, a vasomotor response model in combination with a heating protocol was developed to

  11. Human skin-derived stem cells migrate throughout forebrain and differentiate into astrocytes after injection into adult mouse brain.

    Science.gov (United States)

    Belicchi, Marzia; Pisati, Federica; Lopa, Raffaella; Porretti, Laura; Fortunato, Francesco; Sironi, Manuela; Scalamogna, Mario; Parati, Eugenio A; Bresolin, Nereo; Torrente, Yvan

    2004-08-15

    Recent evidence indicates that neural stem cell properties can be found among a mammalian skin-derived multipotent population. A major barrier in the further characterization of the human skin-derived neural progenitors is the inability to isolate this population based on expression of cell surface markers. Our work has been devoted to purified human skin-derived stem cells that are capable of neural differentiation, based on the presence or absence of the AC133 cell surface marker. The enriched skin-derived AC133(+) cells express the CD34 and Thy-1 antigens. These cells cultured in a growth medium containing epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) proliferate, forming spheres, and differentiate in vitro into neurons, astrocytes, and rarely into oligodendrocytes. Single cells from sphere cultures initiated from human purified AC133(+) cells were replated as single cells and were able to generate new spheres, demonstrating the self-renewing ability of these stem cell populations. Brain engraftment of cells obtained from human purified AC133(+)-derived spheres generated different neural phenotypes: immature neurons and a most abundant population of well differentiated astrocytes. The AC133-derived astrocytes assumed perivascular locations in the frontal cortex. No donor-derived oligodendrocytes were found in the transplanted mouse brains. Several donor small, rounded cells that expressed endothelial markers were found close to the host vessel and near the subventricular zone. Thus, mammalian skin AC133-derived cells behave as a multipotent population with the capacity to differentiate into neural lineages in vitro and, prevalently, endothelium and astrocytes in vivo, demonstrating the great plasticity of these cells and suggesting potential clinical application. Copyright 2004 Wiley-Liss, Inc.

  12. Nuclear microprobe investigation of the penetration of ultrafine zinc oxide into intact and tape-stripped human skin

    Energy Technology Data Exchange (ETDEWEB)

    Szikszai, Z., E-mail: szikszai@atomki.h [Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen (Hungary); Kertesz, Zs. [Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen (Hungary); Bodnar, E. [Department of Dermatology, University of Debrecen, Medical and Health Science Center, Debrecen (Hungary); Major, I. [Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen (Hungary); Borbiro, I. [Abiol Ltd., Debrecen (Hungary); Kiss, A.Z. [Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen (Hungary); Hunyadi, J. [Department of Dermatology, University of Debrecen, Medical and Health Science Center, Debrecen (Hungary)

    2010-06-15

    Ultrafine metal oxides, such as titanium dioxide and zinc oxide are widely used in cosmetic and health products like sunscreens. These oxides are potent UV filters and the small particle size makes the product more transparent compared to formulations containing coarser particles. In the present work the penetration of ultrafine zinc oxide into intact and tape-stripped human skin was investigated using nuclear microprobe techniques, such as proton induced X-ray spectroscopy and scanning transmission ion microscopy. Our results indicate that the penetration of ultrafine zinc oxide, in a hydrophobic basis gel with 48 h application time, is limited to the stratum corneum layer of the intact skin. Removing the stratum corneum partially or entirely by tape-stripping did not cause the penetration of the particles into the deeper dermal layers; the zinc particles remained on the surface of the skin.

  13. Accumulation of sunscreen in human skin after daily applications

    DEFF Research Database (Denmark)

    Bodekær, Mette; Akerström, Ulf; Wulf, Hans Christian

    2012-01-01

    Sunscreen applied to the skin provides a considerable sun protection factor (SPF) even after 8 h. Sunscreen use for consecutive days may therefore result in an accumulation of the product. This study investigated the consequences of accumulation for SPF.......Sunscreen applied to the skin provides a considerable sun protection factor (SPF) even after 8 h. Sunscreen use for consecutive days may therefore result in an accumulation of the product. This study investigated the consequences of accumulation for SPF....

  14. Surface applicator calibration and commissioning of an electronic brachytherapy system for nonmelanoma skin cancer treatment.

    Science.gov (United States)

    Rong, Yi; Welsh, James S

    2010-10-01

    The Xoft Axxent x-ray source has been used for treating nonmelanoma skin cancer since the surface applicators became clinically available in 2009. The authors report comprehensive calibration procedures for the electronic brachytherapy (eBx) system with the surface applicators. The Xoft miniature tube (model S700) generates 50 kVp low-energy x rays. The new surface applicators are available in four sizes of 10, 20, 35, and 50 mm in diameter. The authors' tests include measurements of dose rate, air-gap factor, output stability, depth dose verification, beam flatness and symmetry, and treatment planning with patient specific cutout factors. The TG-61 in-air method was used as a guideline for acquiring nominal dose-rate output at the skin surface. A soft x-ray parallel-plate chamber (PTW T34013) and electrometer was used for the output commissioning. GafChromic EBT films were used for testing the properties of the treatment fields with the skin applicators. Solid water slabs were used to verify the depth dose and cutout factors. Patients with basal cell or squamous cell carcinoma were treated with eBx using a calibrated Xoft system with the low-energy x-ray source and the skin applicators. The average nominal dose-rate output at the skin surface for the 35 mm applicator is 1.35 Gy/min with +/- 5% variation for 16 sources. The dose-rate output and stability (within +/- 5% variation) were also measured for the remaining three applicators. For the same source, the output variation is within 2%. The effective source-surface distance was calculated based on the air-gap measurements for four applicator sizes. The field flatness and symmetry are well within 5%. Percentage depth dose in water was provided by factory measurements and can be verified using solid water slabs. Treatment duration was calculated based on the nominal dose rate, the prescription fraction size, the depth dose percentage, and the cutout factor. The output factor needs to be measured for each case with

  15. Surface applicator calibration and commissioning of an electronic brachytherapy system for nonmelanoma skin cancer treatment

    Energy Technology Data Exchange (ETDEWEB)

    Rong, Yi; Welsh, James S. [Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53792 and University of Wisconsin Cancer Center-Riverview, Riverview Hospital Association, Wisconsin Rapids, Wisconsin 54494 (United States); Department of Human Oncology and Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53792 and University of Wisconsin Cancer Center-Riverview, Riverview Hospital Association, Wisconsin Rapids, Wisconsin 54494 (United States)

    2010-10-15

    Purpose: The Xoft Axxent x-ray source has been used for treating nonmelanoma skin cancer since the surface applicators became clinically available in 2009. The authors report comprehensive calibration procedures for the electronic brachytherapy (eBx) system with the surface applicators. Methods: The Xoft miniature tube (model S700) generates 50 kVp low-energy x rays. The new surface applicators are available in four sizes of 10, 20, 35, and 50 mm in diameter. The authors' tests include measurements of dose rate, air-gap factor, output stability, depth dose verification, beam flatness and symmetry, and treatment planning with patient specific cutout factors. The TG-61 in-air method was used as a guideline for acquiring nominal dose-rate output at the skin surface. A soft x-ray parallel-plate chamber (PTW T34013) and electrometer was used for the output commissioning. GafChromic EBT films were used for testing the properties of the treatment fields with the skin applicators. Solid water slabs were used to verify the depth dose and cutout factors. Patients with basal cell or squamous cell carcinoma were treated with eBx using a calibrated Xoft system with the low-energy x-ray source and the skin applicators. Results: The average nominal dose-rate output at the skin surface for the 35 mm applicator is 1.35 Gy/min with {+-}5% variation for 16 sources. The dose-rate output and stability (within {+-}5% variation) were also measured for the remaining three applicators. For the same source, the output variation is within 2%. The effective source-surface distance was calculated based on the air-gap measurements for four applicator sizes. The field flatness and symmetry are well within 5%. Percentage depth dose in water was provided by factory measurements and can be verified using solid water slabs. Treatment duration was calculated based on the nominal dose rate, the prescription fraction size, the depth dose percentage, and the cutout factor. The output factor needs

  16. Oral Polypodium leucotomos extract decreases ultraviolet-induced damage of human skin

    NARCIS (Netherlands)

    Middelkamp-Hup, Maritza A.; Pathak, Madhu A.; Parrado, Concepcion; Goukassian, David; Rius-Díaz, Francisca; Mihm, Martín C.; Fitzpatrick, Thomas B.; González, Salvador

    2004-01-01

    BACKGROUND: UV radiation induces damage to human skin. Protection of skin by an oral photoprotective agent would have substantial benefits. Objective We investigated the photoprotective effect of oral administration of an extract of the natural antioxidant Polypodium leucotomos (PL). METHODS: A

  17. Human skin condition and its associations with nutrient concentrations in serum and diet

    NARCIS (Netherlands)

    Boelsma, E.; Vijver, L.P.L. van de; Goldbohm, R.A.; Klöpping-Ketelaars, I.A.A.; Hendriks, H.F.J.; Roza, L.

    2003-01-01

    Background: Nutritional factors exert promising actions on the skin, but only scant information is available on the modulating effects of physiologic concentrations of nutrients on the skin condition of humans. Objective: The objective was to evaluate whether nutrient concentrations in serum and

  18. Proteomic allergen-peptide/protein interaction assay for the identification of human skin sensitizers

    NARCIS (Netherlands)

    Dietz, L.; Kinzebach, S.; Ohnesorge, S.; Franke, B.; Goette, I.; Koenig-Gressel, D.; Thierse, H.J.

    2013-01-01

    Modification of proteins by skin sensitizers is a pivotal step in T cell mediated allergic contact dermatitis (ACD). In this process small reactive chemicals interact covalently or non-covalently with cellular or extracellular skin self-proteins or self-peptides to become recognized by the human

  19. Thyrotropin-releasing hormone (TRH promotes wound re-epithelialisation in frog and human skin.

    Directory of Open Access Journals (Sweden)

    Natalia T Meier

    Full Text Available There remains a critical need for new therapeutics that promote wound healing in patients suffering from chronic skin wounds. This is, in part, due to a shortage of simple, physiologically and clinically relevant test systems for investigating candidate agents. The skin of amphibians possesses a remarkable regenerative capacity, which remains insufficiently explored for clinical purposes. Combining comparative biology with a translational medicine approach, we report the development and application of a simple ex vivo frog (Xenopus tropicalis skin organ culture system that permits exploration of the effects of amphibian skin-derived agents on re-epithelialisation in both frog and human skin. Using this amphibian model, we identify thyrotropin-releasing hormone (TRH as a novel stimulant of epidermal regeneration. Moving to a complementary human ex vivo wounded skin assay, we demonstrate that the effects of TRH are conserved across the amphibian-mammalian divide: TRH stimulates wound closure and formation of neo-epidermis in organ-cultured human skin, accompanied by increased keratinocyte proliferation and wound healing-associated differentiation (cytokeratin 6 expression. Thus, TRH represents a novel, clinically relevant neuroendocrine wound repair promoter that deserves further exploration. These complementary frog and human skin ex vivo assays encourage a comparative biology approach in future wound healing research so as to facilitate the rapid identification and preclinical testing of novel, evolutionarily conserved, and clinically relevant wound healing promoters.

  20. New Regions of the Human Genome Linked to Skin Color Variation in Some African Populations

    Science.gov (United States)

    In the first study of its kind, an international team of genomics researchers has identified new regions of the human genome that are associated with skin color variation in some African populations, opening new avenues for research on skin diseases and cancer in all populations.

  1. Thyrotropin-releasing hormone (TRH) promotes wound re-epithelialisation in frog and human skin.

    Science.gov (United States)

    Meier, Natalia T; Haslam, Iain S; Pattwell, David M; Zhang, Guo-You; Emelianov, Vladimir; Paredes, Roberto; Debus, Sebastian; Augustin, Matthias; Funk, Wolfgang; Amaya, Enrique; Kloepper, Jennifer E; Hardman, Matthew J; Paus, Ralf

    2013-01-01

    There remains a critical need for new therapeutics that promote wound healing in patients suffering from chronic skin wounds. This is, in part, due to a shortage of simple, physiologically and clinically relevant test systems for investigating candidate agents. The skin of amphibians possesses a remarkable regenerative capacity, which remains insufficiently explored for clinical purposes. Combining comparative biology with a translational medicine approach, we report the development and application of a simple ex vivo frog (Xenopus tropicalis) skin organ culture system that permits exploration of the effects of amphibian skin-derived agents on re-epithelialisation in both frog and human skin. Using this amphibian model, we identify thyrotropin-releasing hormone (TRH) as a novel stimulant of epidermal regeneration. Moving to a complementary human ex vivo wounded skin assay, we demonstrate that the effects of TRH are conserved across the amphibian-mammalian divide: TRH stimulates wound closure and formation of neo-epidermis in organ-cultured human skin, accompanied by increased keratinocyte proliferation and wound healing-associated differentiation (cytokeratin 6 expression). Thus, TRH represents a novel, clinically relevant neuroendocrine wound repair promoter that deserves further exploration. These complementary frog and human skin ex vivo assays encourage a comparative biology approach in future wound healing research so as to facilitate the rapid identification and preclinical testing of novel, evolutionarily conserved, and clinically relevant wound healing promoters.

  2. Non-enzymatic NO production in human skin: effect of UVA on cutaneous NO stores

    NARCIS (Netherlands)

    Suschek, C.; Opländer, C.; van Faassen, E.E.H.

    2009-01-01

    Nitric oxide (NO) in human skin has been under investigation since first reports of NOS expression in skin tissue in 1992 [1]. NO plays a key role in the dermal response to external stimuli such as heat, ultraviolet (UV) light, or infection, and in healing of abrasions, lesions or burns. Recently, a

  3. An Invariant-Based Damage Model for Human and Animal Skins.

    Science.gov (United States)

    Li, Wenguang; Luo, Xiaoyu Y

    2016-10-01

    Constitutive modelling of skins that account for damage effects is important to provide insight for various clinical applications, such as skin trauma and injury, artificial skin design, skin aging, disease diagnosis, surgery, as well as comparative studies of skin biomechanics between species. In this study, a new damage model for human and animal skins is proposed for the first time. The model is nonlinear, anisotropic, invariant-based, and is based on the Gasser-Ogden-Holzapfel constitutive law initially developed for arteries. Taking account of the mean collagen fibre orientation and its dispersion, the new model can describe a wide range of skins with damage. The model is first tested on the uniaxial test data of human skin and then applied to nine groups of uniaxial test data for the human, swine, rabbit, bovine and rhino skins. The material parameters can be inversely estimated based on uniaxial tests using the optimization method in MATLAB with a root mean square error ranged between 2.15% and 12.18%. A sensitivity study confirms that the fibre orientation dispersion and the mean fibre angle are among the most important factors that influence the behaviour of the damage model. In addition, these two parameters can only be reliably estimated if some histological information is provided. We also found that depending on the location of skins, the tissue damage may be brittle controlled by the fibre breaking limit (i.e., when the fibre stretch is greater than 1.13-1.32, depending on the species), or ductile (due to both the fibre and the matrix damages). The brittle damages seem to occur mostly in the back, and the ductile damages are seen from samples taken from the belly. The proposed constitutive model may be applied to various clinical applications that require knowledge of the mechanical response of human and animal skins.

  4. Spatial temperature distribution in human hairy and glabrous skin after infrared CO2 laser radiation.

    Science.gov (United States)

    Frahm, Ken S; Andersen, Ole K; Arendt-Nielsen, Lars; Mørch, Carsten D

    2010-11-08

    CO2 lasers have been used for several decades as an experimental non-touching pain stimulator. The laser energy is absorbed by the water content in the most superficial layers of the skin. The deeper located nociceptors are activated by passive conduction of heat from superficial to deeper skin layers. In the current study, a 2D axial finite element model was developed and validated to describe the spatial temperature distribution in the skin after infrared CO2 laser stimulation. The geometry of the model was based on high resolution ultrasound scans. The simulations were compared to the subjective pain intensity ratings from 16 subjects and to the surface skin temperature distributions measured by an infrared camera. The stimulations were sensed significantly slower and less intense in glabrous skin than they were in hairy skin (MANOVA, p 0.90, p CO2 laser stimulation intensity, temperature levels and nociceptor activation.

  5. Improvement of Surface skin temperature simulation over the Tibetan Plateau from an energy balance perspective

    Science.gov (United States)

    Zhuo, Haifeng

    2015-04-01

    There has a big cold bias of temperature about reanalysis and simulations over Tibetan Plateau comparing with observations. In order to solve this problem, for the land -- atmosphere interaction in arid and semi-arid region is mainly dominated by heat transfer process, a latest revision of surface sensible heat parameterization introduced by Zeng et al is then used for bare soil in WRFV3 (CLM4) model. Results show that the annual surface skin temperature has approximately up to 2.0 degree improvement on average over Tibetan Plateau. Firstly, the revised scheme changes the energy balance over and around Tibetan Plateau. It significantly reduces the overestimate of surface sensible heat and improves the surface skin temperature simulation, which tends more close to the observation. Secondly, the revised scheme weakens the sensible heat air pump effect of Tibetan Plateau. The diabatic heating reduce and the updraft airflow weaken especially over the southern slope of plateau, meanwhile the clouds thin, the incident solar radiation increases, eventually led to the increase of surface skin temperature in North India in dry season.

  6. Cationic membrane-active peptides - anticancer and antifungal activity as well as penetration into human skin.

    Science.gov (United States)

    Do, Nhung; Weindl, Günther; Grohmann, Lisa; Salwiczek, Mario; Koksch, Beate; Korting, Hans Christian; Schäfer-Korting, Monika

    2014-05-01

    Cationic antimicrobial peptides are ancient natural broad-spectrum antibiotics, and several compounds also exhibit anticancer activity. However, most applications pertain to bacterial infections, and treatment for skin cancer is less frequently considered. The cytotoxicity of melittin, cecropin A, protegrin-1 and histatin 5 against squamous skin cancer cell lines and normal human keratinocytes was evaluated and compared to established drugs. The results show that melittin clearly outperforms 5-fluorouracil regarding antitumor activity. Importantly, combined melittin and 5-fluorouracil enhanced cytotoxic effects on cancer cells and reduced toxicity on normal keratinocytes. Additionally, minimum inhibitory concentrations indicate that melittin also shows superior activity against clinical and laboratory strains of Candida albicans compared to amphotericin B. To evaluate its potential for topical applications, human skin penetration of melittin was investigated ex vivo and compared to two non-toxic cell-penetrating peptides (CPPs), low molecular weight protamine (LMWP) and penetratin. The stratum corneum prevents penetration into viable epidermis over 6 h; however, the peptides gain access to the viable skin after 24 h. Inhibition of digestive enzymes during skin penetration significantly enhances the availability of intact peptide. In conclusion, melittin may represent an innovative agent for non-melanoma skin cancer and infectious skin diseases. In order to develop a drug candidate, skin absorption and proteolytic digestion by skin enzymes need to be addressed. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Melanin Transfer in Human 3D Skin Equivalents Generated Exclusively from Induced Pluripotent Stem Cells.

    Directory of Open Access Journals (Sweden)

    Karl Gledhill

    Full Text Available The current utility of 3D skin equivalents is limited by the fact that existing models fail to recapitulate the cellular complexity of human skin. They often contain few cell types and no appendages, in part because many cells found in the skin are difficult to isolate from intact tissue and cannot be expanded in culture. Induced pluripotent stem cells (iPSCs present an avenue by which we can overcome this issue due to their ability to be differentiated into multiple cell types in the body and their unlimited growth potential. We previously reported generation of the first human 3D skin equivalents from iPSC-derived fibroblasts and iPSC-derived keratinocytes, demonstrating that iPSCs can provide a foundation for modeling a complex human organ such as skin. Here, we have increased the complexity of this model by including additional iPSC-derived melanocytes. Epidermal melanocytes, which are largely responsible for skin pigmentation, represent the second most numerous cell type found in normal human epidermis and as such represent a logical next addition. We report efficient melanin production from iPSC-derived melanocytes and transfer within an entirely iPSC-derived epidermal-melanin unit and generation of the first functional human 3D skin equivalents made from iPSC-derived fibroblasts, keratinocytes and melanocytes.

  8. High-Altitude Living Shapes the Skin Microbiome in Humans and Pigs

    Directory of Open Access Journals (Sweden)

    Bo Zeng

    2017-10-01

    Full Text Available While the skin microbiome has been shown to play important roles in health and disease in several species, the effects of altitude on the skin microbiome and how high-altitude skin microbiomes may be associated with health and disease states remains largely unknown. Using 16S rRNA marker gene sequencing, we characterized the skin microbiomes of people from two racial groups (the Tibetans and the Hans and of three local pig breeds (Tibetan pig, Rongchang pig, and Qingyu pig at high and low altitudes. The skin microbial communities of low-altitude pigs and humans were distinct from those of high-altitude pigs and humans, with five bacterial taxa (Arthrobacter, Paenibacillus, Carnobacterium, and two unclassified genera in families Cellulomonadaceae and Xanthomonadaceae consistently enriched in both pigs and humans at high altitude. Alpha diversity was also significantly lower in skin samples collected from individuals living at high altitude compared to individuals at low altitude. Several of the taxa unique to high-altitude humans and pigs are known extremophiles adapted to harsh environments such as those found at high altitude. Altogether our data reveal that altitude has a significant effect on the skin microbiome of pigs and humans.

  9. Evaluation of skin surface hydration state and barrier function of stratum corneum of dorsa of hands and heels treated with PROTECT X2 skin protective cream.

    Science.gov (United States)

    Kubota, Takahiro

    2012-06-01

    Skin roughness is a term commonly used in Japan to describe a poor skin condition related to a rough and dry skin surface that develops as a result of various damaging effects from the environment or skin inflammation. Recovery from skin roughness requires skin care for a long period, thus it is important to prevent development of such skin changes. PROTECT X2 contains agents used for a protective covering of the skin from frequent hand washing or use of alcohol-based disinfectants. These unique components are also thought to be effective to treat skin roughness of the dorsa of the hands and heels. In the present study, we evaluated the effectiveness of PROTECT X2 to increase skin surface hydration state, as well as enhance the barrier function of the stratum corneum of the dorsa of the hands and heels in elderly individuals. A total of 8 elderly subjects and their caretakers without any skin diseases participated in the study. They applied PROTECT X2 by themselves to the dorsum area of 1 hand and heel 3 to 5 times daily for 1 month, while the opposite sides were left untreated. We measured stratum corneum (SC) hydration and transepidermal water loss (TEWL) before beginning treatment, then 1 week and 1 month after the start of treatment to compare between the treated and untreated skin. SC hydration state after applications of PROTECT X2 was 1.5- to 3.0-fold higher than that of the untreated skin in the dorsa of both hands and heels, indicating that the moisturizing ingredients accompanied by water were replenished in those areas where the cream was applied. Also, TEWL in the dorsum of the hands was 17.0-27.9% lower on the treated side, indicating improvement in SC barrier function. On the basis of these findings, we concluded that PROTECT X2 enhances water-holding in the SC and aids the barrier function of the skin in the dorsum of the hands. In addition, we consider that this formulation is useful for not only protecting the hands from the effects of such agents

  10. The skin microbiome

    OpenAIRE

    Grice, Elizabeth A.; Segre, Julia A.

    2011-01-01

    The skin is the human body’s largest organ, colonized by a diverse milieu of microorganisms, most of which are harmless or even beneficial to their host. Colonization is driven by the ecology of the skin surface, which is highly variable depending on topographical location, endogenous host factors and exogenous environmental factors. The cutaneous innate and adaptive immune responses can modulate the skin microbiota, but the microbiota also functions in educating the immune system. The develo...

  11. Mechanical properties of an artificial vascularized human skin

    Science.gov (United States)

    Passot, A.; Cabodevila, G.

    2011-05-01

    In order to make blood sample tests an artificial skin similar to that of the baby's heel is modeled and realized. The most superficial bloodstream and the two main layers of the skin -epidermis and dermis- have to be recreated. Studies and capillaroscopies of the baby's heel give characteristics of these layers and the bloodstream. The skin is viscohyperelastic, but the choice of materials that will be used is based on the Young's modulus. The epidermis layer is based on a stronger less adhesive silicon rubber Elastosil. The dermis layer is composed of a mixture based on a very soft sticky silicon rubber Silgel and Sylgard. The mixture of Silgel with 5% Sylgard has an elastic modulus of 48 kPa which is similar to that of the dermis. The artificial skin is an assembly of several layers including a layer of Sylgard that is structured by a mold representing the capillary network and adapted to manufacturing processes in a clean room. Each layer is deposited by spin coating and is combined with the other through adhesion. Mechanical tests such as tension are performed to verify the mechanical properties of the artificial skin.

  12. Aromatase activity in human skin fibroblasts grown in cell culture.

    Science.gov (United States)

    Berkovitz, G D; Brown, T R; Fujimoto, M

    1987-01-01

    Recent studies in this laboratory have described an unusual kindred in which gynecomastia resulted from abnormally elevated levels of extraglandular aromatase activity. In order to better understand the molecular mechanisms responsible for the abnormal aromatase activity in these and other patients, we explored the aromatase activity of genital skin fibroblasts. Our studies demonstrate that the kinetic parameters for aromatase in skin are similar to those of other cultured cells and suggest that skin is an important site of extraglandular aromatase activity. These cells also contain 5 alpha-reductase activity and androgen receptors and are, therefore, a model for androgen action and metabolism. For example, they provided a system for the study of the potency and specificity of the aromatase inhibitors 4-OHA and MDL 18,962. Finally, the influence of DEX on aromatase in genital skin fibroblasts differs in some important respects from the pattern of control observed in adipose tissue stromal-vascular cells. These findings suggest that investigating the molecular mechanisms for the regulation of aromatase in skin may provide unique information about the control of the enzyme.

  13. In vitro dermal absorption of decabromodiphenyl ethane in rat and human skin

    Data.gov (United States)

    U.S. Environmental Protection Agency — In vitro dermal absorption of decabromodiphenyl ethane in rat and human skin. This dataset is associated with the following publication: Knudsen, G., J.M. Sanders,...

  14. Novel Inhibitory Effect of N-(2-Hydroxycyclohexylvaliolamine on Melanin Production in a Human Skin Model

    Directory of Open Access Journals (Sweden)

    Bum-Ho Bin

    2014-07-01

    Full Text Available Hyper-pigmentation causes skin darkness and medical disorders, such as post-inflammatory melanoderma and melasma. Therefore, the development of anti-melanogenic agents is important for treating these conditions and for cosmetic production. In our previous paper, we demonstrated that the anti-diabetic drug voglibose, a valiolamine derivative, is a potent anti-melanogenic agent. In addition, we proposed an alternative screening strategy to identify valiolamine derivatives with high skin permeability that act as anti-melanogenic agents when applied topically. In this study, we synthesized several valiolamine derivatives with enhanced lipophilicity and examined their inhibitory effects in a human skin model. N-(2-hydroxycyclohexylvaliolamine (HV possesses a stronger inhibitory effect on melanin production than voglibose in a human skin model, suggesting that HV is a more potent anti-melanogenic agent for the skin.

  15. Probe pressure effects on human skin diffuse reflectance and fluorescence spectroscopy measurements

    OpenAIRE

    Lim, Liang; Nichols, Brandon; Rajaram, Narasimhan; Tunnell, James W.

    2011-01-01

    Diffuse reflectance and fluorescence spectroscopy are popular research techniques for noninvasive disease diagnostics. Most systems include an optical fiber probe that transmits and collects optical spectra in contact with the suspected lesion. The purpose of this study is to investigate probe pressure effects on human skin spectroscopic measurements. We conduct an in-vivo experiment on human skin tissue to study the short-term (30 s) effects of probe pressure on diffuse reflectance and fluor...

  16. Dietary water affects human skin hydration and biomechanics

    Directory of Open Access Journals (Sweden)

    Palma L

    2015-08-01

    Full Text Available Lídia Palma,1 Liliana Tavares Marques,1 Julia Bujan,2,3 Luís Monteiro Rodrigues1,4 1CBIOS – Research Center for Health Science and Technologies, Universidade Lusófona, Campo Grande, Lisboa, Portugal; 2Department of Medicine and Medical Specialities, Universidad de Alcalá de Henares, Madrid, Spain; 3CIBER-BBN, Madrid, España, Spain; 4Department of Pharmacological Sciences, School of Pharmacy, Universidade de Lisboa, Lisboa, Portugal Abstract: It is generally assumed that dietary water might be beneficial for the health, especially in dermatological (age preventing terms. The present study was designed to quantify the impact of dietary water on major indicators of skin physiology. A total of 49 healthy females (mean 24.5±4.3 years were selected and characterized in terms of their dietary daily habits, especially focused in water consumption, by a Food Frequency Questionnaire. This allowed two groups to be set – Group 1 consuming less than 3,200 mL/day (n=38, and Group 2 consuming more than 3,200 mL/day (n=11. Approximately 2 L of water were added to the daily diet of Group 2 individuals for 1 month to quantify the impact of this surplus in their skin physiology. Measurements involving epidermal superficial and deep hydration, transepidermal water loss, and several biomechanical descriptors were taken at day 0 (T0, 15 (T1, and 30 (T2 in several anatomical sites (face, upper limb, and leg. This stress test (2 L/day for 30 days significantly modified superficial and deep skin hydration, especially in Group 1. The same impact was registered with the most relevant biomechanical descriptors. Thus, in this study, it is clear that higher water inputs in regular diet might positively impact normal skin physiology, in particular in those individuals with lower daily water consumptions. Keywords: dietary water, water consume, skin hydration, TEWL, skin biomechanics

  17. Relation between HLA genes, human skin volatiles and attractiveness of humans to malaria mosquitoes.

    Science.gov (United States)

    Verhulst, Niels O; Beijleveld, Hans; Qiu, Yu Tong; Maliepaard, Chris; Verduyn, Willem; Haasnoot, Geert W; Claas, Frans H J; Mumm, Roland; Bouwmeester, Harro J; Takken, Willem; van Loon, Joop J A; Smallegange, Renate C

    2013-08-01

    Chemical cues are considered to be the most important cues for mosquitoes to find their hosts and humans can be ranked for attractiveness to mosquitoes based on the chemical cues they emit. Human leukocyte antigen (HLA) genes are considered to be involved in the regulation of human body odor and may therefore affect human attractiveness to mosquitoes, and hence, affect the force of malaria transmission. In the present study the correlations between HLA profiles, human skin volatiles and human attractiveness to the malaria mosquito Anopheles gambiae Giles sensu stricto were examined. Skin emanations of 48 volunteers were collected by rubbing a foot over glass beads. Previously the attractiveness of these emanations to An. gambiae was determined. In this study, the chemical composition of these emanations was determined by gas chromatography-mass spectroscopy (GC-MS) and blood samples of all volunteers were taken for HLA analysis. Hierarchical cluster analysis (HCA), partial least squares discriminant analysis (PLS-DA), Fisher's exact test and random forest regression were used to test for correlations between individuals classified as either highly or poorly attractive to mosquitoes and their HLA profile and volatile composition. HLA profiling suggests that people carrying HLA gene Cw∗07 are more attractive to mosquitoes. GC-MS revealed that limonene, 2-phenylethanol and 2-ethyl-1-hexanol were associated with individuals that were poorly attractive to An.gambiae and lactic acid, 2-methylbutanoic acid, tetradecanoic acid and octanal with individuals that were highly attractive. Such compounds offer potential for disruption of mosquito behavior in malaria intervention programs. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Repair of DNA damage in light sensitive human skin diseases

    Energy Technology Data Exchange (ETDEWEB)

    Horkay, I.; Varga, L.; Tam' asi P., Gundy, S.

    1978-12-01

    Repair of uv-light induced DNA damage and changes in the semiconservative DNA synthesis were studied by in vitro autoradiography in the skin of patients with lightdermatoses (polymorphous light eruption, porphyria cutanea tarda, erythropoietic protoporphyria) and xeroderma pigmentosum as well as in that of healthy controls. In polymorphous light eruption the semiconservative DNA replication rate was more intensive in the area of the skin lesions and in the repeated phototest site, the excision repair synthesis appeared to be unaltered. In cutaneous prophyrias a decreased rate of the repair incorporation could be detected. Xeroderma pigmentosum was characterized by a strongly reduced repair synthesis.

  19. Human in vitro skin organ culture as a model system for evaluating DNA repair.

    Science.gov (United States)

    Liu, Hannah; Tuchinda, Papapit; Fishelevich, Rita; Harberts, Erin; Gaspari, Anthony A

    2014-06-01

    UV-exposures result in accumulation of genetic lesions that facilitate the development of skin cancer. Numerous pharmacologic agents are currently under development to both inhibit formation of DNA lesions and enhance repair. Drugs must be evaluated in vitro, currently performed in cell culture systems, before being tested on humans. Current systems do not account for the architecture and diverse cellularity of intact human skin. To establish a novel, functionally viable, and reproducible in vitro skin organ culture system for studying the effects of various pharmacologic agents on DNA repair. Human skin was obtained from neonatal foreskins. Intact skin punches derived from foreskins were cultured in vitro prior to exposure to UV-irradiation, and evaluated for DNA-damage using a DNA dot blot. Serial skin biopsies were obtained from patients with actinic keratoses treated with topical imiquimod. Expression of immune-stimulating and DNA repair genes was evaluated in ex vivo and in vitro samples. DNA dot blots revealed active repair of UV induced lesions in our in vitro skin organ culture. The photo-protective effect of sunscreen was detected, while imiquimod treatment did not enhance DNA repair in vitro. The DNA repair molecules XPA and XPF were up-regulated in the skin of imiquimod treated patients with actinic keratoses and imiquimod treated bone marrow-derived cell lines, but not keratinocytes. Our in vitro human skin organ culture model detected repair of UV-induced DNA lesions, and may be easily adapted to investigate various photo-protective drugs intended to prevent or treat skin cancer. Copyright © 2014 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  20. Retrieving Clear-Sky Surface Skin Temperature for Numerical Weather Prediction Applications from Geostationary Satellite Data

    Directory of Open Access Journals (Sweden)

    Baojuan Shan

    2013-01-01

    Full Text Available Atmospheric models rely on high-accuracy, high-resolution initial radiometric and surface conditions for better short-term meteorological forecasts, as well as improved evaluation of global climate models. Remote sensing of the Earth’s energy budget, particularly with instruments flown on geostationary satellites, allows for near-real-time evaluation of cloud and surface radiation properties. The persistence and coverage of geostationary remote sensing instruments grant the frequent retrieval of near-instantaneous quasi-global skin temperature. Among other cloud and clear-sky retrieval parameters, NASA Langley provides a non-polar, high-resolution land and ocean skin temperature dataset for atmospheric modelers by applying an inverted correlated k-distribution method to clear-pixel values of top-of-atmosphere infrared temperature. The present paper shows that this method yields clear-sky skin temperature values that are, for the most part, within 2 K of measurements from ground-site instruments, like the Southern Great Plains Atmospheric Radiation Measurement (ARM Infrared Thermometer and the National Climatic Data Center Apogee Precision Infrared Thermocouple Sensor. The level of accuracy relative to the ARM site is comparable to that of the Moderate-resolution Imaging Spectroradiometer (MODIS with the benefit of an increased number of daily measurements without added bias or increased error. Additionally, matched comparisons of the high-resolution skin temperature product with MODIS land surface temperature reveal a level of accuracy well within 1 K for both day and night. This confidence will help in characterizing the diurnal and seasonal biases and root-mean-square differences between the retrievals and modeled values from the NASA Goddard Earth Observing System Version 5 (GEOS-5 in preparation for assimilation of the retrievals into GEOS-5. Modelers should find the immediate availability and broad coverage of these skin temperature

  1. Structural and biophysical characteristics of human skin in maintaining proper epidermal barrier function

    Directory of Open Access Journals (Sweden)

    Magdalena Boer

    2016-02-01

    Full Text Available The complex structure of human skin and its physicochemical properties turn it into an efficient outermost defence line against exogenous factors, and help maintain homeostasis of the human body. This role is played by the epidermal barrier with its major part – stratum corneum. The condition of the epidermal barrier depends on individual and environmental factors. The most important biophysical parameters characterizing the status of this barrier are the skin pH, epidermal hydration, transepidermal water loss and sebum excretion. The knowledge of biophysical skin processes may be useful for the implementation of prophylactic actions whose aim is to restore the barrier function.

  2. A UV-Independent Topical Small-Molecule Approach for Melanin Production in Human Skin

    Directory of Open Access Journals (Sweden)

    Nisma Mujahid

    2017-06-01

    Full Text Available The presence of dark melanin (eumelanin within human epidermis represents one of the strongest predictors of low skin cancer risk. Topical rescue of eumelanin synthesis, previously achieved in “redhaired” Mc1r-deficient mice, demonstrated significant protection against UV damage. However, application of a topical strategy for human skin pigmentation has not been achieved, largely due to the greater barrier function of human epidermis. Salt-inducible kinase (SIK has been demonstrated to regulate MITF, the master regulator of pigment gene expression, through its effects on CRTC and CREB activity. Here, we describe the development of small-molecule SIK inhibitors that were optimized for human skin penetration, resulting in MITF upregulation and induction of melanogenesis. When topically applied, pigment production was induced in Mc1r-deficient mice and normal human skin. These findings demonstrate a realistic pathway toward UV-independent topical modulation of human skin pigmentation, potentially impacting UV protection and skin cancer risk.

  3. Predicting human epidermal melanin concentrations for different skin tones

    CSIR Research Space (South Africa)

    Smit, Jacoba E

    2011-07-01

    Full Text Available In the past 50 years lasers has found numerous applications in medicine. One of their advantages is their use for minimalistic or non-invasive diagnosis and treatment. Often that means light penetration through skin and the correct dose required...

  4. Hendersonula Toruloidea Infection of Human Skin and Nails

    Directory of Open Access Journals (Sweden)

    S M Singh

    1980-01-01

    Full Text Available Four cases of skin and nail infection by Hendersonula toruloidea are described from India. Infections were confined to the feet which showed scaling and dystrophic nails. The presence of brown hyphae with knobbled swellings in the nail tissue and repeated isolation of H. toraloidea in pure culture are taken as evidence that this fungus was invading the tissues.

  5. Dietary water affects human skin hydration and biomechanics

    Science.gov (United States)

    Palma, Lídia; Marques, Liliana Tavares; Bujan, Julia; Rodrigues, Luís Monteiro

    2015-01-01

    It is generally assumed that dietary water might be beneficial for the health, especially in dermatological (age preventing) terms. The present study was designed to quantify the impact of dietary water on major indicators of skin physiology. A total of 49 healthy females (mean 24.5±4.3 years) were selected and characterized in terms of their dietary daily habits, especially focused in water consumption, by a Food Frequency Questionnaire. This allowed two groups to be set – Group 1 consuming less than 3,200 mL/day (n=38), and Group 2 consuming more than 3,200 mL/day (n=11). Approximately 2 L of water were added to the daily diet of Group 2 individuals for 1 month to quantify the impact of this surplus in their skin physiology. Measurements involving epidermal superficial and deep hydration, transepidermal water loss, and several biomechanical descriptors were taken at day 0 (T0), 15 (T1), and 30 (T2) in several anatomical sites (face, upper limb, and leg). This stress test (2 L/day for 30 days) significantly modified superficial and deep skin hydration, especially in Group 1. The same impact was registered with the most relevant biomechanical descriptors. Thus, in this study, it is clear that higher water inputs in regular diet might positively impact normal skin physiology, in particular in those individuals with lower daily water consumptions. PMID:26345226

  6. Elastic wave induced by friction as a signature of human skin ageing and gender effect.

    Science.gov (United States)

    Djaghloul, M; Morizot, F; Zahouani, H

    2016-08-01

    In this work, we propose an innovative approach based on a rotary tribometer coupled with laser velocimetry for measuring the elastic wave propagation on the skin. The method is based on a dynamic contact with the control of the normal force (Fn ), the contact length and speed. During the test a quantification of the friction force is produced. The elastic wave generated by friction is measured at the surface of the skin 35 mm from the source of friction exciter. In order to quantify the spectral range and the energy property of the wave generated, we have used laser velocimetry whose spot laser diameter is 120 μm, which samples the elastic wave propagation at a frequency which may reach 100 kHz. In this configuration, the speaker is the friction exciter and the listener the laser velocimetry. In order to perform non-invasive friction tests, the normal stress has been set to 0.3 N and the rotary velocity to 3 revolutions per second, which involves a sliding velocity of 63 mm/s. This newly developed innovative tribometer has been used for the analysis of the elastic wave propagation induced by friction on human skin during chronological ageing and gender effect. Measurements in vivo have been made on 60 healthy men and women volunteers, aged from 25 to 70. The results concerning the energy of the elastic wave signature induced by friction show a clear difference between the younger and older groups in the range of a low band of frequencies (0-200 Hz). The gender effect was marked by a 20% decrease in the energy of elastic wave propagation in the female group. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Development of a Full-Thickness Human Skin Equivalent In Vitro Model Derived from TERT-Immortalized Keratinocytes and Fibroblasts

    NARCIS (Netherlands)

    Reijnders, C.M.A.; van Lier, A.; Roffel, S.; Kramer, D.; Scheper, R.J.; Gibbs, S.

    2015-01-01

    Currently, human skin equivalents (HSEs) used for in vitro assays (e.g., for wound healing) make use of primary human skin cells. Limitations of primary keratinocytes and fibroblasts include availability of donor skin and donor variation. The use of physiologically relevant cell lines could solve

  8. Segmentation of hyper-pigmented spots in human skin using automated cluster analysis

    Science.gov (United States)

    Gossage, Kirk W.; Weissman, Jesse; Velthuizen, Robert

    2009-02-01

    The appearance and color distribution of skin are important characteristics that affect the human perception of health and vitality. Dermatologists and other skin researchers often use color and appearance to diagnose skin conditions and monitor the efficacy of procedures and treatments. Historically, most skin color and chromophore measurements have been performed using reflectance spectrometers and colorimeters. These devices acquire a single measurement over an integrated area defined by an aperture, and are therefore poorly suited to measure the color of pigmented lesions or other blemishes. Measurements of spots smaller than the aperture will be washed out with background, and spots that are larger may not be adequately sampled unless the blemish is homogenous. Recently, multispectral imaging devices have become available for skin imaging. These devices are designed to image regions of skin and provide information about the levels of endogenous chromophores present in the image field of view. This data is presented as four images at each measurement site including RGB color, melanin, collagen, and blood images. We developed a robust segmentation technique that can segment skin blemishes in these images and provide more precise values of melanin, blood, and collagen by only analyzing the segmented region of interest. Results from hundreds of skin images show this to be a robust automated segmentation technique over a range of skin tones and shades.

  9. Surface chemistry and reactivity of skin-passed hot dip galvanized coating

    OpenAIRE

    Mataigne, Jean-Michel; Vaché, Véronique; Repoux, Monique

    2009-01-01

    La publication originale est disponible sur le site http://www.revue-metallurgie.org; International audience; GI coatings are covered by a very thin aluminum layer that precipitates after wiping. Anisotropic growing of zinc crystals during solidification induces a strong basal texture in GI coatings. Skin-pass induced changes in GI coating surface chemistry, crystallography and reactivity have been assessed. Local coating analyses have been performed (XPS, TOF-SIMS) in order to describe local...

  10. Dried human skin fibroblasts as a new substratum for functional culture of hepatic cells.

    Science.gov (United States)

    Wencel, Agnieszka; Zakrzewska, Karolina Ewa; Samluk, Anna; Noszczyk, Bartłomiej Henryk; Pijanowska, Dorota Genowefa; Pluta, Krzysztof Dariusz

    2017-01-01

    The primary hepatocytes culture is still one of the main challenges in toxicology studies in the drug discovery process, development of in vitro models to study liver function, and cell-based therapies. Isolated hepatocytes display a rapid decline in viability and liver-specific functions including albumin production, conversion of ammonia to urea, and activity of the drug metabolizing enzymes. A number of methods have been developed in order to maintain hepatocytes in their highly differentiated state in vitro. Optimization of culture conditions includes a variety of media formulations and supplements, growth surface coating with the components of extracellular matrix or with synthetic polymers, three-dimensional growth scaffolds and decellularized tissues, and coculture with other cell types required for the normal cell-cell interactions. Here we propose a new substratum for hepatic cells made by drying confluent human skin fibroblasts' culture. This growth surface coating, prepared using maximally simplified procedure, combines the advantages of the use of extracellular matrices and growth factors/cytokines secreted by the feeder layer cells. In comparison to the hepatoma cells grown on a regular tissue culture plastic, cells cultured on the dried fibroblasts were able to synthesize albumin in larger quantities and to form greater number of apical vacuoles. Unlike the coculture with the living feeder layer cells, the number of cells grown on the new substratum was not reduced after fourteen days of culture. This fact could make the dried fibroblasts coating an ideal candidate for the substrate for non-dividing human hepatocytes.

  11. [Increase in skin surface temperature in spinal anesthesia. Predictive value for probability of surgical tolerance].

    Science.gov (United States)

    Penno, A; Arumugam, M; Antweiler, G; Laubert, T; Habermann, J; Bruch, H-P

    2012-09-01

    Spinal anesthesia causes sympathetic blockade which leads to changes in the local temperature of the skin surface due to hyperemia. These changes in skin temperature were used in a newly developed method for estimating the level of analgesia. A total of 11 patients who were scheduled for surgical procedures of the lower extremities with symmetrical spinal anesthesia were included in the clinical study. By means of an electronic digital multi-channel body temperature measurement device with eight high precision temperature sensors placed on defined dermatomes, patient skin temperature was continuously measured at 2 s intervals and documented before, during and for 45 min after spinal anesthesia. Simultaneously, a neurological pin-prick test was carried on at regular intervals every 2 min on the defined dermatomes to calculate the correlation between the effects of analgesia and corresponding changes in skin temperature. The analyzed correlations showed that there is a minimum of 1.05°C temperature difference before and after spinal anesthesia especially on the lower extremities (foot, knee, inguinal) of patient dermatomes. The collected data of varying temperature differences were systematically evaluated using statistical software which led to a deeper understanding of the interdependency between temperature differences at different dermatomes. These interdependencies of temperature differences were used to develop a systematic analgesia level measurement algorithm. The algorithm calculates the skin temperature differences at specified dermatomes to find the accurate level of analgesia and also to find the forward and reverse progresses of analgesia. The developed mathematical method shows that it is possible to predict the level of analgesia up to an accuracy of 95% after spinal anesthesia. Therefore, it can be concluded that systematic processing of skin temperature data, collected at defined dermatomes can be used as a promising parameter for predicting

  12. All-weather land surface skin temperatures from a combined analysis of microwave and infrared satellite observations

    Science.gov (United States)

    The surface skin temperature (Ts) is a key parameter at the land-atmosphere interface. Upwelling longwave radiation directly epends upon Ts. Energy exchanges at the land-surface boundary are largely controlled by the difference between Ts and the surface air temperature, the air and the surface reac...

  13. Fermentation of Propionibacterium acnes, a commensal bacterium in the human skin microbiome, as skin probiotics against methicillin-resistant Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Muya Shu

    Full Text Available Bacterial interference creates an ecological competition between commensal and pathogenic bacteria. Through fermentation of milk with gut-friendly bacteria, yogurt is an excellent aid to balance the bacteriological ecosystem in the human intestine. Here, we demonstrate that fermentation of glycerol with Propionibacterium acnes (P. acnes, a skin commensal bacterium, can function as a skin probiotic for in vitro and in vivo growth suppression of USA300, the most prevalent community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA. We also promote the notion that inappropriate use of antibiotics may eliminate the skin commensals, making it more difficult to fight pathogen infection. This study warrants further investigation to better understand the role of fermentation of skin commensals in infectious disease and the importance of the human skin microbiome in skin health.

  14. Hair Follicle Morphogenesis in the Treatment of Mouse Full-Thickness Skin Defects Using Composite Human Acellular Amniotic Membrane and Adipose Derived Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Wu Minjuan

    2016-01-01

    Full Text Available Early repair of skin injury and maximal restoration of the function and appearance have become important targets of clinical treatment. In the present study, we observed the healing process of skin defects in nude mice and structural characteristics of the new skin after transplantation of isolated and cultured adipose derived mesenchymal stem cells (ADMSCs onto the human acellular amniotic membrane (AAM. The result showed that ADMSCs were closely attached to the surface of AAM and grew well 24 h after seeding. Comparison of the wound healing rate at days 7, 14, and 28 after transplantation showed that ADMSCs seeded on AAM facilitated the healing of full-thickness skin wounds more effectively as compared with either hAM or AAM alone, indicating that ADMSCs participated in skin regeneration. More importantly, we noticed a phenomenon of hair follicle development during the process of skin repair. Composite ADMSCs and AAM not only promoted the healing of the mouse full-thickness defects but also facilitated generation of the appendages of the affected skin, thus promoting restoration of the skin function. Our results provide a new possible therapy idea for the treatment of skin wounds with respect to both anatomical regeneration and functional restoration.

  15. More about the developing of invisible lipstick-contaminated lipmarks on human skin: the usefulness of fluorescent dyes.

    Science.gov (United States)

    Navarro, E; Castelló, A; López-Alfaro, J A; Verdú, F

    2007-08-01

    At the present time fingerprints are one of the simplest, and most reliable means of identification. Increasingly, crime scene investigators look for palm, foot, ear or lip prints. With regard to lip prints, the use, very common today, of protective or permanent lipsticks allow the production an invisible lipmark (or invisible lipstick-contaminated lipmark) which is possible to develop. Some results have already been published about developers useful for different kinds of surfaces (both porous and non-porous) as well as those which are more efficient in case of old or recent prints. The latest studies are about the developing on human skin, and they prove the usefulness of lysochromes (specifically Sudan Black) for the develop of recent invisible lipstick-contaminated lipmarks on corpse skin. This study attempts to determine the efficiency of fluorescent reagents to develop invisible lipstick-contaminated lipmark on human skin. Results show that REDescent Fluorescent Latent Prints Powder is effective for obtaining recent invisible lipstick-contaminated lip mark on the skin of deceased.

  16. [Preliminary study of biomechanic property on human forethigh skin].

    Science.gov (United States)

    Liu, C; Chen, H

    1997-12-01

    HLC0-I biomechanical living-tissues testing mechanic was adopted for testing the biomechanical property of normal adult forethigh skin. The figures acquired were calculated using one dimension strain energy function and the constitutive equation of mono-way stress and strain was established. The results showed that the relationship between stress and strain could be expressed by the exponential function. The rise of stress was not evident when the strain was lower than 1.2, but the stress rose much sharply when the strain was higher than 1.2. The curves were nonlinear. This suggests that when we sew up a wound or perform skin transplantation, the strain should be lower than 1.2.

  17. Ultrathin conformal devices for precise and continuous thermal characterization of human skin

    Science.gov (United States)

    Webb, R. Chad; Bonifas, Andrew P.; Behnaz, Alex; Zhang, Yihui; Yu, Ki Jun; Cheng, Huanyu; Shi, Mingxing; Bian, Zuguang; Liu, Zhuangjian; Kim, Yun-Soung; Yeo, Woon-Hong; Park, Jae Suk; Song, Jizhou; Li, Yuhang; Huang, Yonggang; Gorbach, Alexander M.; Rogers, John A.

    2013-10-01

    Precision thermometry of the skin can, together with other measurements, provide clinically relevant information about cardiovascular health, cognitive state, malignancy and many other important aspects of human physiology. Here, we introduce an ultrathin, compliant skin-like sensor/actuator technology that can pliably laminate onto the epidermis to provide continuous, accurate thermal characterizations that are unavailable with other methods. Examples include non-invasive spatial mapping of skin temperature with millikelvin precision, and simultaneous quantitative assessment of tissue thermal conductivity. Such devices can also be implemented in ways that reveal the time-dynamic influence of blood flow and perfusion on these properties. Experimental and theoretical studies establish the underlying principles of operation, and define engineering guidelines for device design. Evaluation of subtle variations in skin temperature associated with mental activity, physical stimulation and vasoconstriction/dilation along with accurate determination of skin hydration through measurements of thermal conductivity represent some important operational examples.

  18. The Effects of Mucopolysaccharide Polysulphate on Hydration and Elasticity of Human Skin

    Directory of Open Access Journals (Sweden)

    Rungsima Wanitphakdeedecha

    2011-01-01

    Full Text Available Background. Mucopolysaccharide polysulphate (MPS has been used in medicine as an anti-inflammatory and antithrombotic agent for over 50 years. Its chemical structure permits considerable hydrogen bonding with adjacent water molecules, which effectively leads to hydration of the surrounding tissue. In addition, it stimulates endogenous hyaluronate synthesis, resulting in an increase in water-binding capacity and viscoelasticity of the skin. Objective. To study the efficacy of 0.1% MPS on hydration and elasticity of human skin. Methods. The first part of this study was a randomized double blind placebo-controlled study which included 60 female volunteers aged 30–45 years with dry skin, defined by Corneometer CM 825. The volunteers were treated with either 0.1% MPS or vehicle control. All subjects were asked to apply 1 g of cream to their face twice daily for a total period of 4 weeks. Skin hydration and elasticity were measured at baseline and week 4 with Corneometer CM 825 and cutometer MPA 580, respectively, at forehead and both cheeks. The second part of this study focused on the efficacy of 0.1% MPS on skin hydration after single application. 20 female volunteers aged 30–45 years with dry skin, defined by Corneometer CM 825, were recruited to the study. All subjects were asked to apply 2 g of 0.1% MPS cream on entirely randomly selected forearm. Skin hydration at the middle of both forearms was measured at baseline, immediately after application, and every 1 hour after application for a period of 10 hours. Results. 57 subjects (28 in vehicle control group, 29 in MPS completed treatment protocol. The baseline skin hydration of both groups was not significantly different (P=0.47. Hower, there was a statistically significant difference in skin hydration at 4 weeks between MPS and placebo group (P=0.01. Skin elasticity was significantly improved at week 4 in both groups (vehicle-control, P<0.01, and MPS, P<0.01. However, no

  19. Deformations experienced in the human skin, adipose tissue, and fascia in osteopathic manipulative medicine.

    Science.gov (United States)

    Chaudhry, Hans; Bukiet, Bruce; Ji, Zhiming; Stecco, Antonio; Findley, Thomas W

    2014-10-01

    Osteopathic manipulative medicine techniques involve compressive and tangential forces to target the fascia. These forces are transmitted to the skin and adipose tissue before the fascia is encountered. Knowing the extent of deformation of these 2 tissue layers relative to the fascia will assist osteopathic physicians in evaluating techniques for manual therapies and adjusting these therapies to reduce patient discomfort and improve results. To determine the magnitude of the forces transmitted to the skin, adipose tissue, and fascia, and to determine the magnitude of deformation produced in the skin and adipose tissue relative to the fascia using a mathematical model. The large deformation theory of elasticity, valid for 3-dimensional deformations, was used to evaluate the forces that need to be applied such that a specified deformation is produced in any region of the skin, adipose tissue, or fascia layers. Similarly, if the forces are specified, then the deformation produced can be determined. The normal and tangential forces required to produce a deformation of 9% compression and 4% shear for the skin were 50 N and 11 N, respectively. Normal and tangential forces of about 100 N and 22 N were found for a similar deformation of fascia. For adipose tissue, these forces were 36 N and 8 N, respectively. In addition, the skin experienced more compression and shear-about 1.5 times as much as the fascia, and the adipose tissue experienced about 2.5 to 3.5 times the deformation of the fascia and 50% more than the skin when a given force was applied to the skin. The forces applied to the surface of the skin were transmitted through this layer and the adipose layer entirely to the fascia. Therefore, the skin and adipose tissue experienced the same magnitude of force as the fascia. However, the skin and adipose tissue experienced more compression and shear than the fascia. © 2014 The American Osteopathic Association.

  20. Microneedles permit transdermal delivery of a skin-impermeant medication to humans.

    Science.gov (United States)

    Wermeling, Daniel P; Banks, Stan L; Hudson, David A; Gill, Harvinder S; Gupta, Jyoti; Prausnitz, Mark R; Stinchcomb, Audra L

    2008-02-12

    Drugs with poor oral bioavailability usually are administered by hypodermic injection, which causes pain, poor patient compliance, the need for trained personnel, and risk of infectious disease transmission. Transdermal (TD) delivery provides an excellent alternative, but the barrier of skin's outer stratum corneum (SC) prevents delivery of most drugs. Micrometer-scale microneedles (MNs) have been used to pierce animal and human cadaver skin and thereby enable TD delivery of small molecules, proteins, DNA, and vaccines for systemic action. Here, we present a clinical study of MN-enhanced delivery of a medication to humans. Naltrexone (NTX) is a potent mu-opioid receptor antagonist used to treat opiate and alcohol dependence. This hydrophilic and skin-impermeant molecule was delivered from a TD patch to healthy human subjects with and without pretreatment of the skin with MNs. Whereas delivery from a standard NTX TD patch over a 72-h period yielded undetectable drug plasma levels, pretreatment of skin with MNs achieved steady-state plasma concentrations within 2 h of patch application and were maintained for at least 48 h. The MNs and NTX patch were well tolerated with mild systemic and application site side effects. The MN arrays were painless upon administration and not damaged during skin insertion, and no MNs were broken off into the skin. This human proof-of-concept study demonstrates systemic administration of a hydrophilic medication by MN-enhanced TD delivery. These findings set the stage for future human studies of skin-impermeant medications and biopharmaceuticals for clinical applications.

  1. Surface Patterning: Controlling Fluid Flow Through Dolphin and Shark Skin Biomimicry

    Science.gov (United States)

    Gamble, Lawren; Lang, Amy; Bradshaw, Michael; McVay, Eric

    2013-11-01

    Dolphin skin is characterized by circumferential ridges, perpendicular to fluid flow, present from the crest of the head until the tail fluke. When observing a cross section of skin, the ridges have a sinusoidal pattern. Sinusoidal grooves have been proven to induce vortices in the cavities that can help control flow separation which can reduce pressure drag. Shark skin, however, is patterned with flexible scales that bristle up to 50 degrees with reversed flow. Both dolphin ridges and shark scales are thought to help control fluid flow and increase swimming efficiency by delaying the separation of the boundary layer. This study investigates how flow characteristics can be altered with bio-inspired surface patterning. A NACA 4412 hydrofoil was entirely patterned with transverse sinusoidal grooves, inspired by dolphin skin but scaled so the cavities on the model have the same Reynolds number as the cavities on a swimming shark. Static tests were conducted at a Reynolds number of approximately 100,000 and at varying angles of attack. The results were compared to the smooth hydrofoil case. The flow data was quantified using Digital Particle Image Velocimetry (DPIV). The results of this study demonstrated that the patterned hydrofoil experienced greater separation than the smooth hydrofoil. It is hypothesize that this could be remediated if the pattern was placed only after the maximum thickness of the hydrofoil. Funding through NSF REU grant 1062611 is gratefully acknowledged.

  2. Changes in Skin Surface Temperature during Muscular Endurance indicated Strain – An Explorative Study

    Directory of Open Access Journals (Sweden)

    Michael Fröhlich

    2014-07-01

    Full Text Available Introduction: Non-contact thermography enables the diagnosis of the distribution of skin surface temperature during athletic movement. Resistance exercise results in stress of required musculature, which is supposed to be measurable thermographically in terms of skin surface temperature change. Objective: This study aims to evaluate the application of thermography to analyze changes in skin temperature, representing specific muscle groups, during and after resistance exercise. Method: Thirteen male participants (age: 27.1 ± 4.9 years, height: 181.5 ± 5.7 cm, mass: 74.8 ± 7.4 kg completed the study. On 5 separate visits to the laboratory, participants performed one of 5 resistance exercise to target specific muscles (M. pectoralis major, M. rectus abdominis, M. trapezius, M. erector spinae, M. quadriceps femoris. The exercise protocol consisted of 3 sets of 20 repetitions, with 1 minute rest between exercise sets. The average skin surface temperature above the muscle groups used was thermographically determined using standard methods at 7 time points; pre-exercise, immediately following each exercise set, and post exercise (2, 3, and 6 minutes after the finale exercise set. The measurement areas were standardized using anatomic reference points. Results: From an inferential statistical point of view, no significant change in the average temperature caused by the applied resistance training was found for the individual muscle groups over time at the individual measurement times (all P>0.08. However, thermography showed a characteristic chronological temperature curve for the five body areas between measurement times, as well as a distinctive spatial temperature distribution over the measurement areas. Discussion: Based on the thermographic image data and the characteristic temperature curve, it is possible to identify the primarily used functional musculature after device-controlled resistance training. Therefore, thermography seems to be

  3. Essential role of RAB27A in determining constitutive human skin color.

    Directory of Open Access Journals (Sweden)

    Yasuko Yoshida-Amano

    Full Text Available Human skin color is predominantly determined by melanin produced in melanosomes within melanocytes and subsequently distributed to keratinocytes. There are many studies that have proposed mechanisms underlying ethnic skin color variations, whereas the processes involved from melanin synthesis in melanocytes to the transfer of melanosomes to keratinocytes are common among humans. Apart from the activities in the melanogenic rate-limiting enzyme, tyrosinase, in melanocytes and the amounts and distribution patterns of melanosomes in keratinocytes, the abilities of the actin-associated factors in charge of melanosome transport within melanocytes also regulate pigmentation. Mutations in genes encoding melanosome transport-related molecules, such as MYO5A, RAB27A and SLAC-2A, have been reported to cause a human pigmentary disease known as Griscelli syndrome, which is associated with diluted skin and hair color. Thus we hypothesized that process might play a role in modulating skin color variations. To address that hypothesis, the correlations of expression of RAB27A and its specific effector, SLAC2-A, to melanogenic ability were evaluated in comparison with tyrosinase, using human melanocytes derived from 19 individuals of varying skin types. Following the finding of the highest correlation in RAB27A expression to the melanogenic ability, darkly-pigmented melanocytes with significantly higher RAB27A expression were found to transfer significantly more melanosomes to keratinocytes than lightly-pigmented melanocytes in co-culture and in human skin substitutes (HSSs in vivo, resulting in darker skin color in concert with the difference observed in African-descent and Caucasian skins. Additionally, RAB27A knockdown by a lentivirus-derived shRNA in melanocytes concomitantly demonstrated a significantly reduced number of transferred melanosomes to keratinocytes in co-culture and a significantly diminished epidermal melanin content skin color intensity (

  4. Essential role of RAB27A in determining constitutive human skin color.

    Science.gov (United States)

    Yoshida-Amano, Yasuko; Hachiya, Akira; Ohuchi, Atsushi; Kobinger, Gary P; Kitahara, Takashi; Takema, Yoshinori; Fukuda, Mitsunori

    2012-01-01

    Human skin color is predominantly determined by melanin produced in melanosomes within melanocytes and subsequently distributed to keratinocytes. There are many studies that have proposed mechanisms underlying ethnic skin color variations, whereas the processes involved from melanin synthesis in melanocytes to the transfer of melanosomes to keratinocytes are common among humans. Apart from the activities in the melanogenic rate-limiting enzyme, tyrosinase, in melanocytes and the amounts and distribution patterns of melanosomes in keratinocytes, the abilities of the actin-associated factors in charge of melanosome transport within melanocytes also regulate pigmentation. Mutations in genes encoding melanosome transport-related molecules, such as MYO5A, RAB27A and SLAC-2A, have been reported to cause a human pigmentary disease known as Griscelli syndrome, which is associated with diluted skin and hair color. Thus we hypothesized that process might play a role in modulating skin color variations. To address that hypothesis, the correlations of expression of RAB27A and its specific effector, SLAC2-A, to melanogenic ability were evaluated in comparison with tyrosinase, using human melanocytes derived from 19 individuals of varying skin types. Following the finding of the highest correlation in RAB27A expression to the melanogenic ability, darkly-pigmented melanocytes with significantly higher RAB27A expression were found to transfer significantly more melanosomes to keratinocytes than lightly-pigmented melanocytes in co-culture and in human skin substitutes (HSSs) in vivo, resulting in darker skin color in concert with the difference observed in African-descent and Caucasian skins. Additionally, RAB27A knockdown by a lentivirus-derived shRNA in melanocytes concomitantly demonstrated a significantly reduced number of transferred melanosomes to keratinocytes in co-culture and a significantly diminished epidermal melanin content skin color intensity (ΔL* = 4.4) in the

  5. Exploring the potentials of nurture: 2(nd) and 3(rd) generation explant human skin equivalents.

    Science.gov (United States)

    Danso, Mogbekeloluwa O; van Drongelen, Vincent; Mulder, Aat; Gooris, Gert; van Smeden, Jeroen; El Ghalbzouri, Abdoelwaheb; Bouwstra, Joke A

    2015-02-01

    Explant human skin equivalents (Ex-HSEs) can be generated by placing a 4mm skin biopsy onto a dermal equivalent. The keratinocytes migrate from the biopsy onto the dermal equivalent, differentiate and form the epidermis of 1(st) generation Ex-HSEs. This is especially suitable for the expansion of skin material from which only small fragments of skin can be harvested e.g. diseased skin. We evaluated whether 2(nd) and 3(rd) generation Ex-HSEs can also be generated from a single skin biopsy whilst maintaining the epidermal properties of 1(st) generation Ex-HSEs and native human skin. 2(nd) generation Ex-HSEs were produced by placing a biopsy from the 1(st) generation Ex-HSE onto a new dermal equivalent. Likewise, the 3(rd) generation Ex-HSEs were generated from a 2(nd) generation Ex-HSE biopsy. We show for the first time that Ex-HSEs can be passaged to the 2(nd) and 3(rd) generation and display similar epidermal morphology and expression of differentiation markers as in native human skin and 1(st) generation Ex-HSEs except for involucrin. The 2(nd) and 3(rd) generation Ex-HSEs also show many similarities with 1(st) generation Ex-HSEs in lipid properties e.g. presence of all lipid classes, similar fatty acid chain length distribution and lamellar lipid organization. However, some differences arise in increased level of hexagonal lateral packing and a change in ceramide profiling. The changes in specific lipid classes were also accompanied by changes in the expression of the enzymes responsible for their synthesis. The expansion of skin biopsies to the 2(nd) and 3(rd) generation Ex-HSEs could be a promising method to expand valuable epidermal tissue to analyze morphological and differentiation parameters in the native epidermis. Copyright © 2015 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  6. French Maritime Pine Bark Extract (Pycnogenol®) Effects on Human Skin: Clinical and Molecular Evidence.

    Science.gov (United States)

    Grether-Beck, Susanne; Marini, Alessandra; Jaenicke, Thomas; Krutmann, Jean

    2016-01-01

    Nutritional strategies to benefit skin health are of growing importance. Current approaches mainly involve nutritional supplements containing antioxidants which were initially designed to protect human skin against ultraviolet radiation-induced damage. Within recent years, however, a growing number of studies suggests that the beneficial effects of these products clearly extend beyond photoprotection. In this review we take the nutritional supplement Pycnogenol®, which is based on an extract prepared from French marine pine bark extract, as an example to illustrate this development. Accordingly, the existing data provide compelling evidence that Pycnogenol® intake does not only provide photoprotection, but may be used to (i) reduce hyperpigmentation of human skin and (ii) improve skin barrier function and extracellular matrix homeostasis. © 2015 S. Karger AG, Basel.

  7. Kanglaite attenuates UVB-induced down-regulation of aquaporin-3 in cultured human skin keratinocytes

    Science.gov (United States)

    SHAN, SHI-JUN; XIAO, TING; CHEN, JOHN; GENG, SHI-LING; LI, CHANG-PING; XU, XUEGANG; HONG, YUXIAO; JI, CHAO; GUO, YING; WEI, HUACHEN; LIU, WEI; LI, DAPENG; CHEN, HONG-DUO

    2012-01-01

    Ultraviolet (UV) radiation plays an important role in the pathogenesis of skin photoaging. Depending on the wavelength of UV, the epidermis is affected primarily by UVB. One major characteristic of photoaging is the dehydration of the skin. Membrane-inserted water channels (aquaporins) are involved in this process. In this study we demonstrated that UVB radiation induced aquaporin-3 (AQP3) down-regulation in cultured human skin keratinocytes. Kanglaite is a mixture consisting of extractions of Coix Seed, which is an effective anti-neoplastic agent and can inhibit the activities of protein kinase C and NF-κB. We demonstrated that Kanglaite inhibited UVB-induced AQP3 down-regulation of cultured human skin keratinocytes. Our findings provide a potential new agent for anti-photoaging. The related molecular mechanisms remain to be further elucidated. PMID:22211241

  8. Automated epidermis segmentation in histopathological images of human skin stained with hematoxylin and eosin

    Science.gov (United States)

    Kłeczek, Paweł; Dyduch, Grzegorz; Jaworek-Korjakowska, Joanna; Tadeusiewicz, Ryszard

    2017-03-01

    Background: Epidermis area is an important observation area for the diagnosis of inflammatory skin diseases and skin cancers. Therefore, in order to develop a computer-aided diagnosis system, segmentation of the epidermis area is usually an essential, initial step. This study presents an automated and robust method for epidermis segmentation in whole slide histopathological images of human skin, stained with hematoxylin and eosin. Methods: The proposed method performs epidermis segmentation based on the information about shape and distribution of transparent regions in a slide image and information about distribution and concentration of hematoxylin and eosin stains. It utilizes domain-specific knowledge of morphometric and biochemical properties of skin tissue elements to segment the relevant histopathological structures in human skin. Results: Experimental results on 88 skin histopathological images from three different sources show that the proposed method segments the epidermis with a mean sensitivity of 87 %, a mean specificity of 95% and a mean precision of 57%. It is robust to inter- and intra-image variations in both staining and illumination, and makes no assumptions about the type of skin disorder. The proposed method provides a superior performance compared to the existing techniques.

  9. Diffuse Reflectance Spectroscopy of Human Skin Using a Commercial Fiber Optic Spectrometer

    Science.gov (United States)

    Atencio, J. A. Delgado; Rodríguez, M. Cunill; Montiel, S. Vázquez y.; Gutiérrez, J. L.; Martínez, F.; Gutiérrez, B.; Orozco, E.; Castro, Jorge; Rodríguez, A. Cornejo

    2008-08-01

    Diffuse reflectance spectroscopy is a reliable and easy to implement technique in human tissue characterization. In this work we evaluate the performance of the commercial USB4000 miniature fiber optic spectrometer in the in-vivo measurement of the diffuse reflectance spectra of different healthy skin sites and lesions in a population of 54 volunteers. Results show, that this spectrometer reproduces well the typical signatures of skin spectra over the 400-1000 nm region. Remarkable spectral differences exist between lesions and normal surrounding skin. A diffusion-based model was used to simulate reflectance spectra collected by the optical probe of the system.

  10. Acoustic absorption measurement of human hair and skin within the audible frequency range.

    Science.gov (United States)

    Katz, B F

    2000-11-01

    Utilizing the two-microphone impedance tube method, the acoustic absorption of human skin and hair is measured in the frequency range 1-6 kHz. Various locations on a number of human subjects are measured to determine if the presence of bone or an air pocket affects the acoustic absorption of human skin. The absorption coefficient of human hair is also measured. Additional techniques are utilized to minimize errors due to sample mounting methods. Techniques are employed to minimize potential errors in sensor and sample locations. The results of these measurements are compared to relevant historical papers on similar investigations. Results for skin measurements compare well with previous work. Measured hair absorption data do not agree with previous work in the area but do coincide with expected trends, which previous works do not.

  11. Vascular effects of leukotriene D4 in human skin

    DEFF Research Database (Denmark)

    Bisgaard, H

    1987-01-01

    as a mediator of the axon reflex, and show that LTD4 causes a direct vasodilatory effect that is not mediated via histamine or cyclooxygenase products. The laser-Doppler flowmeter was applied for dynamic studies of the vasopressor response in the skin during a Valsalva maneuver, and the relative changes...... in blood flow were confirmed by control estimates of the blood flow rate by a 133xenon washout method. The pressor response to a Valsalva maneuver was reversed by local nerve block, but not affected by LTD4. Therefore LTD4 did not interfere with the sympathetic activity on the cutaneous vessels...

  12. Transdermal iontophoresis of the dopamine agonist 5-OH-DPAT in human skin in vitro

    NARCIS (Netherlands)

    Nugroho, AK; Li, L; Dijkstra, D; Wikstrom, H; Danhof, M; Bouwstra, JA

    2005-01-01

    The feasibility of transdermal iontophoretic delivery of a potent dopamine agonist 5-OH-DPAT was studied in vitro in side by side diffusion cells across human stratum corneum (HSC) and dermatomed human skin (DHS) according to the following protocol: 6 h of passive diffusion, 9 h of iontophoresis and

  13. Tumor necrosis factor alpha (TNF alpha) in human skin : A comparison of different antibodies for immunohistochemistry

    NARCIS (Netherlands)

    van der Laan, N; de Leij, LFMH; Buurman, W; Timens, W; ten Duis, HJ

    Conflicting results have been reported regarding the localization and presence of TNF alpha in normal human skin, To study TNF alpha expression, we tested a panel of antibodies directed against human TNF alpha, First, antibodies were tested for immunoreactivity on cytospots of isolated

  14. Demodex folliculorum and topical treatment: acaricidal action evaluated by standardized skin surface biopsy.

    Science.gov (United States)

    Forton, F; Seys, B; Marchal, J L; Song, A M

    1998-03-01

    A standardized skin surface biopsy was performed in 34 patients suffering from skin diseases with high Demodex folliculorum density (Dd) > 5D/cm2 before, during and after topical treatment. The patients were randomized into six comparable groups to study six topical treatments: metronidazole 2%, permethrin 1%, sublimed sulphur 10%, lindane 1%, crotamiton 10% and benzyl benzoate (BB) 10%. Their acaricidal activity was measured according to three criteria: (i) for each treatment, decrease of Dd to under the normal threshold (treatment, a significant decrease in Dd; and (iii) comparison of the relative difference in Dd between treatments. These three criteria converged to establish the acaricidal activity of BB on D. folliculorum; the efficacy of crotamiton was demonstrated by the second criterion. An important irritating effect was observed with BB and sulphur.

  15. A novel model of wound healing in the SCID mouse using a cultured human skin substitute.

    Science.gov (United States)

    Windsor, Martin L; Eisenberg, Mark; Gordon-Thomson, Clare; Moore, Geoffrey P M

    2009-02-01

    Studies of skin graft behaviour in rodent excisional wound models are limited by the dominance of wound contracture and graft sloughing as primary healing responses. To slow skin contraction, polytetrafluoroethylene (Teflon) rings were inserted into dorso-lateral full-thickness wounds in SCID mice. Cultured skin substitutes (OrCel), composed of cultured human keratinocytes and fibroblasts in a bovine collagen sponge, were implanted within the rings. Examination and histology of grafts 14 days later showed graft take in four of six recipients, with 90% epithelialization and wound contraction of 31-47%. Immunohistochemical studies, using human-specific antisera to distinguish graft from host tissues, showed that regenerated tissue was predominantly human. Staining with anticytokeratin, revealed a multilayered, stratified neoepidermis. HBG were identified in keratinocytes in all epidermal layers. Langerhans cells were absent. Antihuman vimentin, used as a fibroblast marker, confirmed that cells of the neodermis were primarily of human origin. Neoepidermal keratinocytes, primarily in the basal and suprabasal layers, were also stained. Results suggest that the poly(tetrafluoroethylene) ring inhibited graft sloughing and provided a more favourable environment for the skin substitute to regenerate a substantially normal human skin.

  16. Two-wavelength Raman detector for noninvasive measurements of carotenes and lycopene in human skin

    Science.gov (United States)

    Ermakov, Igor V.; Ermakova, Maia R.; Gellermann, Werner

    2005-04-01

    Carotenoids are an important part of the antioxidant system in human skin. Carotenoid molecules, provided by fruits and vegetables, are potent free radical quenchers that accumulate in the body. If not balanced by carotenoids and other antioxidants, free radicals may cause premature skin aging, oxidative cell damage, and even skin cancers. As carotenoids depletion may predispose a person to cancer or other disease, rapid and noninvasive measurement of carotenoid level in skin may be of preventive or diagnostic help. At the very least, such measurement can be used to obtain a biomarker for healthy levels of fruit and vegetable consumption. Recently we have developed noninvasive optical technique based on Raman spectroscopy. In this paper we describe compact optical detector for clinical applications that utilizes two-wavelength excitation. It selectively measures the two most prominent skin carotenoids found in the human skin, lycopene and carotenes. According to the medical literature, these two compounds may play different roles in the human body and be part of different tissue defense mechanisms. Dual-wavelength Raman measurements reveal significant differences in the carotenoid composition of different subjects.

  17. Protection effect of cosmetics on human skin under simulated rigorous environment.

    Science.gov (United States)

    Cheng, Yan; Dong, Yi-Yang; Dong, Mei-Xian; Wang, Chao; Su, Ning; Sun, Yuan-Tao; Liu, Juan; Zheng, Hong-Yan; Schrader, Andreas; Rohr, Mathias; Liu, Wei

    2008-02-01

    The efficacy of cosmetics on human skin measured under normal mild laboratory environment might be discounted by exterior environment factors such as wind, UV exposure, etc. Few studies have focused on the 'genuine' efficacy of cosmetics on human skin during exposure to external rigorous environment. The aim of this study was to develop a model for the evaluation of the efficacy of cosmetics on human skin under simulated rigorous environment. We measured skin water content and transepidermal water loss (TEWL) before and after products application under simulated windy and sub-erythema UV exposure treatment in a constant temperature and humidity laboratory. The results showed that the products had higher water content and lower TEWL at 2, 4 and 8 h of products application, and ameliorated the skin moisturization situation after a 3-week continuous use of the products. In addition, the products might protect the skin to maintain the normal water content and TEWL under the simulated windy or sub-erythema UV exposure treatment in our laboratory when compared with untreated area. Our data indicate that this model may provide a more accurate evaluation for the genuine moisturizing effect of cosmetics under external natural climate.

  18. Implementation and analysis of relief patterns of the surface of benign and malignant lesions of the skin by microtopography

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Pacheco, Maria del Carmen Lopez [Laboratorio de CitopatologIa Ambiental, Departamento de MorfologIa, ENCB-IPN, UP Lazaro Cardenas, Casco de Santo Tomas, 11340 (Mexico); Martins-Costa, Manuel Filipe Pereira da Cunha [Departamento de Fisica, Universidad do Minho, Escola de Ciencias Campus de Gualtar-PT-4710-057 Braga (Portugal); Zapata, Aura Judith Perez [Laboratorio de CitopatologIa Ambiental, Departamento de MorfologIa, ENCB-IPN, UP Lazaro Cardenas, Casco de Santo Tomas, 11340 (Mexico); Cherit, Judith DomInguez [Departamento de DermatologIa, Hospital General Dr Manuel Gea Gonzalez, Calzada de Tlalpan No 4800, 14000 (Mexico); Gallegos, Eva Ramon [Laboratorio de CitopatologIa Ambiental, Departamento de MorfologIa, ENCB-IPN, UP Lazaro Cardenas, Casco de Santo Tomas, 11340 (Mexico)

    2005-12-07

    The objective of this study was to be able to distinguish between healthy skin tissue and malignant ones, furthermore determining a unique pattern of roughness for each skin lesion by microtopographic analysis of the skin surface of Mexican patients during the period from April to October 2002. The standard technique used in this study for the diagnosis of skin cancer and the comparison of the results was the haematoxylin-eosin histopathological technique. Latex impressions were taken from skin lesions as well as from the healthy skin of each patient to serve as control samples. These impressions were analysed by the MICROTOP.03.MFC microtopographic system inspection. It was observed that when the tumour becomes rougher, more malign will be the lesion. On average, the melanoma present an increase of roughness of 67% compared to healthy skin, obtaining a roughness relation of 1:2.54. The percentage decreases to 49% (49%, 1:60) in the case of basal cell carcinoma and to 40% in pre-malignant lesions such as melanocytic nevus (40%, 1:150). In benign lesions such as the seborrhoea keratosis only a small increase in roughness was noted (4%, 1:0.72). Microtopographic inspection of the skin surface can be considered as a complementary diagnostic technique for skin cancer.

  19. Ultra-pure soft water ameliorates atopic skin disease by preventing metallic soap deposition in NC/Tnd mice and reduces skin dryness in humans.

    Science.gov (United States)

    Tanaka, Akane; Matsuda, Akira; Jung, Kyungsook; Jang, Hyosun; Ahn, Ginnae; Ishizaka, Saori; Amagai, Yosuke; Oida, Kumiko; Arkwright, Peter D; Matsuda, Hiroshi

    2015-09-01

    Mineral ions in tap water react with fatty acids in soap, leading to the formation of insoluble precipitate (metallic soap) on skin during washing. We hypothesised that metallic soap might negatively alter skin conditions. Application of metallic soap onto the skin of NC/Tnd mice with allergic dermatitis further induced inflammation with elevation of plasma immunoglobulin E and proinflammatory cytokine expression. Pruritus and dryness were ameliorated when the back of mice was washed with soap in Ca2+- and Mg2+-free ultra-pure soft water (UPSW). Washing in UPSW, but not tap water, also protected the skin of healthy volunteers from the soap deposition. Furthermore, 4 weeks of showering with UPSW reduced dryness and pruritus of human subjects with dry skin. Washing with UPSW may be therapeutically beneficial in patients with skin troubles.

  20. A preclinical model for the analysis of genetically modified human skin in vivo.

    Science.gov (United States)

    Del Rio, Marcela; Larcher, Fernando; Serrano, Fernando; Meana, Alvaro; Muñoz, Marta; Garcia, Marta; Muñoz, Evangelina; Martin, Clara; Bernad, Antonio; Jorcano, José Luis

    2002-05-20

    Although skin is perhaps the most accessible of all somatic tissues for therapeutic gene transfer, it is a challenging site when attempting gene delivery. In addition to the transience of gene expression, important obstacles to cutaneous gene therapy have included the inability to sustain gene expression in a large proportion of keratinocytes within a given skin compartment. In this study, we have developed a novel experimental strategy that allows long-term regeneration of entirely genetically engineered human skin on the backs of NOD/SCID mice. Primary human keratinocytes were infected with a retroviral vector encoding the enhanced green fluorescent protein (EGFP) produced by transient transfection of 293T cells. EGFP expression allowed cell-sorting selection of a polyclonal population of productively transduced keratinocytes that were assembled in a live fibroblast-containing fibrin dermal matrix and orthotopically grafted onto mice. Epifluorescent illumination of the transplanted zone allowed in vivo monitoring of the genetically modified graft. EGFP-positive human skin was present on mice for 22 weeks after grafting. In addition, frozen sections prepared from the grafts displayed consistently strong EGFP-based fluorescence in all epidermal strata at every time point examined. Persistence of transgene expression was further confirmed through EGFP protein immunodetection. Purified EGFP-positive keratinocytes grafted as part of the fibrin-based artificial skin were capable of generating multilayer human epidermis on mice, with well-developed granulosum and corneum strata, and clearly defined rete ridges. Finally, the large proportion of transduced keratinocytes in our grafts allowed us to study, for the first time, the long-term in vivo clonal reconstitution pattern of the regenerated skin. Analysis of the provirus insertion sites indicates that a discrete number of epidermal stem cell clones was responsible for the maintenance of human skin regenerated in NOD

  1. Reactivating the extracellular matrix synthesis of sulfated glycosaminoglycans and proteoglycans to improve the human skin aspect and its mechanical properties

    Directory of Open Access Journals (Sweden)

    Chajra H

    2016-12-01

    Full Text Available Hanane Chajra,1 Daniel Auriol,1 Francine Joly,2 Aurélie Pagnon,3 Magda Rodrigues,4 Sophie Allart,4 Gérard Redziniak,5 Fabrice Lefevre1 1Libragen, Induchem (Givaudan Active Beauty, Toulouse, 2Sephra Pharma, Puteaux, 3Novotec, Bron, 4Centre de Physiopathologie de Toulouse-Purpan, Toulouse, 5Cosmetic Inventions, Antony, France Background: The aim of this study was to demonstrate that a defined cosmetic composition is able to induce an increase in the production of sulfated glycosaminoglycans (sGAGs and/or proteoglycans and finally to demonstrate that the composition, through its combined action of enzyme production and synthesis of macromolecules, modulates organization and skin surface aspect with a benefit in antiaging applications. Materials and methods: Gene expression was studied by quantitative reverse transcription polymerase chain reaction using normal human dermal fibroblasts isolated from a 45-year-old donor skin dermis. De novo synthesis of sGAGs and proteoglycans was determined using Blyscan™ assay and/or immunohistochemical techniques. These studies were performed on normal human dermal fibroblasts (41- and 62-year-old donors and on human skin explants. Dermis organization was studied either ex vivo on skin explants using bi-photon microscopy and transmission electron microscopy or directly in vivo on human volunteers by ultrasound technique. Skin surface modification was investigated in vivo using silicone replicas coupled with macrophotography, and the mechanical properties of the skin were studied using Cutometer. Results: It was first shown that mRNA expression of several genes involved in the synthesis pathway of sGAG was stimulated. An increase in the de novo synthesis of sGAGs was shown at the cellular level despite the age of cells, and this phenomenon was clearly related to the previously observed stimulation of mRNA expression of genes. An increase in the expression of the corresponding core protein of decorin, perlecan

  2. The altered landscape of the human skin microbiome in patients with primary immunodeficiencies.

    Science.gov (United States)

    Oh, Julia; Freeman, Alexandra F; Park, Morgan; Sokolic, Robert; Candotti, Fabio; Holland, Steven M; Segre, Julia A; Kong, Heidi H

    2013-12-01

    While landmark studies have shown that microbiota activate and educate host immunity, how immune systems shape microbiomes and contribute to disease is incompletely characterized. Primary immunodeficiency (PID) patients suffer recurrent microbial infections, providing a unique opportunity to address this issue. To investigate the potential influence of host immunity on the skin microbiome, we examined skin microbiomes in patients with rare monogenic PIDs: hyper-IgE (STAT3-deficient), Wiskott-Aldrich, and dedicator of cytokinesis 8 syndromes. While specific immunologic defects differ, a shared hallmark is atopic dermatitis (AD)-like eczema. We compared bacterial and fungal skin microbiomes (41 PID, 13 AD, 49 healthy controls) at four clinically relevant sites representing the major skin microenvironments. PID skin displayed increased ecological permissiveness with altered population structures, decreased site specificity and temporal stability, and colonization with microbial species not observed in controls, including Clostridium species and Serratia marcescens. Elevated fungal diversity and increased representation of opportunistic fungi (Candida, Aspergillus) supported increased PID skin permissiveness, suggesting that skin may serve as a reservoir for the recurrent fungal infections observed in these patients. The overarching theme of increased ecological permissiveness in PID skin was counterbalanced by the maintenance of a phylum barrier in which colonization remained restricted to typical human-associated phyla. Clinical parameters, including markers of disease severity, were positively correlated with prevalence of Staphylococcus, Corynebacterium, and other less abundant taxa. This study examines differences in microbial colonization and community stability in PID skin and informs our understanding of host-microbiome interactions, suggesting a bidirectional dialogue between skin commensals and the host organism.

  3. Effect of ethnicity, gender and age on the amount and composition of residual skin surface components derived from sebum, sweat and epidermal lipids.

    Science.gov (United States)

    Shetage, Satyajit S; Traynor, Matthew J; Brown, Marc B; Raji, Mahad; Graham-Kalio, Diepiriye; Chilcott, Robert P

    2014-02-01

    The superficial layer on the skin surface, known as the acid mantle, comprises a mixture of sebum, sweat, corneocyte debris and constituents of natural moisturizing factor. Thus, the phrase 'residual skin surface components' (RSSC) is an appropriate term for the mixture of substances recovered from the skin surface. There is no general agreement about the effects of ethnicity, gender and age on RSSC. The aim of this human volunteer study was to evaluate RSSC in relation to ethnicity, gender and age. A suitable acquisition medium for RSSC collection was identified and samples of RSSC were subsequently analysed using gas chromatography-mass spectrometry (GC-MS) and gravimetry. A total of 315 volunteers participated in the study from a range of self-declared ethnic backgrounds. Six acquisition media were compared to determine the most suitable media for RSSC collection. The effect of age, gender and ethnicity on RSSC collection was evaluated by gravimetric analysis while GC-MS was used to determine the composition of RSSC. Of the six candidate materials assessed, cigarette paper provided the most practical and reproducible sample acquisition medium. There was no significant difference in the amount of RSSC collected when based on gender and ethnicity and no significant correlation between RSSC recovery and age. Up to 49 compounds were detected from human RSSC when analysed by GC-MS. The results of the present study suggest that RSSC can be effectively collected using cigarette paper and analysed by GC-MS. Ethnicity, gender and age had no significant impact on the quantity of RSSC recovered from the skin surface. © 2013 The Authors. Skin Research and Technology published by John Wiley & Sons Ltd.

  4. Criminalystic: effectiveness of lysochromes on the developing of invisible lipstick-contaminated lipmarks on human skin. A preliminary study.

    Science.gov (United States)

    Navarro, Esperanza; Castelló, Ana; López, Jose L; Verdú, Fernando

    2006-04-20

    Latent prints are an important evidence for identification. Nowadays, the technical means, the implementation of image processing techniques and the use of database makes it possible to detect and get information from some prints that seem to be useless at first sight. On the other hand, the possibility of using the print as a DNA source has to be considered, so as to double its identifying value. Human skin is a particularly difficult surface for developing this kind of evidences. Although different methods for locating and developing latent fingerprints on the skin have been already described, it has not been found any method, at the revised bibliography, to obtain and develop invisible lipmarks, that is, lipmarks from protective lipstick, or permanent or long-lasting lipstick. The aim of the work that follows is to determine the effectiveness of several reagents for developing invisible lipmarks on the corpses' skin. Preliminary results show that, under the described experimental conditions, the reagents used, Sudan III, Oil Red O and Sudan Black, are effective for obtaining recent latent lip prints on corpse's skin.

  5. Finite element model to study temperature distribution in skin and deep tissues of human limbs.

    Science.gov (United States)

    Agrawal, Mamta; Pardasani, K R

    2016-12-01

    The temperature of body tissues is viewed as an indicator of tissue response in clinical applications since ancient times. The tissue temperature depends on various physical and physiological parameters like blood flow, metabolic heat generation, thermal conductivity of tissues, shape and size of organs etc. In this paper a finite element model has been proposed to study temperature distribution in skin and deep tissues of human limbs. The geometry of human limb is taken as elliptical tapered shape. It is assumed that outer surface of the limb is exposed to the environment. The appropriate boundary conditions have been framed based on physical conditions of the problem. The model has been developed for a three dimensional steady state case. Hexahedral circular sectoral elements are used to discretize the region. The results have been computed to obtain temperature profiles and study the relation of tissue temperature with the parameters like atmospheric temperature, rate of evaporation, thickness of tissues layers and shape of the limb. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Predictive performance for human skin sensitizing potential of the human cell line activation test (h-CLAT).

    Science.gov (United States)

    Nukada, Yuko; Ashikaga, Takao; Sakaguchi, Hitoshi; Sono, Sakiko; Mugita, Nanae; Hirota, Morihiko; Miyazawa, Masaaki; Ito, Yuichi; Sasa, Hitoshi; Nishiyama, Naohiro

    2011-12-01

    Recent changes in regulatory restrictions and social opposition to animal toxicology experiments have driven the need for reliable in vitro tests for predicting the skin sensitizing potentials of a wide variety of industrial chemicals. Previously, we developed the human cell line activation test (h-CLAT) as a cell-based assay to predict the skin sensitizing potential of chemicals, and showed the correspondence between the h-CLAT and the murine local lymph node assay results. This study was conducted to investigate the predictive performance of the h-CLAT for human skin sensitizing potential. We selected a total of 66 test chemicals with known human sensitizing potential, and tested all chemicals with the h-CLAT. We then evaluated the performance of the h-CLAT in predicting human sensitizing potential. Forty-five of 51 tested sensitizers were positive in the h-CLAT, indicating relatively high sensitivity. Also, 10 of 15 non-sensitizers were correctly detected as negative. The overall agreement between human data and h-CLAT outcome was 83%. Furthermore, the h-CLAT could accurately predict the human sensitizing potential of 23 tested chemicals that were amines, heterocyclic compounds, or sulfur compounds. Our data indicate the utility of the h-CLAT for predicting the human skin sensitizing potential of a variety of chemicals. © 2011 John Wiley & Sons A/S.

  7. Integrating a human thermoregulatory model with a clothing model to predict core and skin temperatures.

    Science.gov (United States)

    Yang, Jie; Weng, Wenguo; Wang, Faming; Song, Guowen

    2017-05-01

    This paper aims to integrate a human thermoregulatory model with a clothing model to predict core and skin temperatures. The human thermoregulatory model, consisting of an active system and a passive system, was used to determine the thermoregulation and heat exchanges within the body. The clothing model simulated heat and moisture transfer from the human skin to the environment through the microenvironment and fabric. In this clothing model, the air gap between skin and clothing, as well as clothing properties such as thickness, thermal conductivity, density, porosity, and tortuosity were taken into consideration. The simulated core and mean skin temperatures were compared to the published experimental results of subject tests at three levels of ambient temperatures of 20 °C, 30 °C, and 40 °C. Although lower signal-to-noise-ratio was observed, the developed model demonstrated positive performance at predicting core temperatures with a maximum difference between the simulations and measurements of no more than 0.43 °C. Generally, the current model predicted the mean skin temperatures with reasonable accuracy. It could be applied to predict human physiological responses and assess thermal comfort and heat stress. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Microcystin-LR affects properties of human epidermal skin cells crucial for regenerative processes.

    Science.gov (United States)

    Kozdęba, Marcin; Borowczyk, Julia; Zimoląg, Eliza; Wasylewski, Marcin; Dziga, Dariusz; Madeja, Zbigniew; Drukala, Justyna

    2014-03-01

    The occurrence of cyanobacterial toxic peptides, including microcystins (MCs), is an emerging health issue due to the eutrophication of water bodies. MCs have a strong influence on human cells, predominantly hepatocytes, however, toxicity was also observed in kidney, lung and dermal skin cells. Skin as the most external barrier of the human body is responsible for the maintenance of homeostasis of the whole organism. Simultaneously, skin cells may be the most exposed to MCs during recreational activity. The aim of this study was to examine the impact of MC-LR on processes indispensable for normal skin function and regeneration, namely, viability, migration and actin cytoskeleton organization of human keratinocytes. The results showed that short exposure to MC-LR does not affect proliferation of human skin keratinocytes but it is toxic after longer incubation in dose-dependent manner. Total disruption of the actin cytoskeleton was observed under the same MC-LR concentration. Furthermore, keratinocyte migration was inhibited at MC-LR concentrations of 50 μM after incubation for only 4 h. Some of the negative impacts of MC-LR on the examined cell processes may be partly reversible. The observed effects, regarding the possible high exposition of keratinocytes to toxins including MCs, are severe and may cause diverse health problems. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Differential attraction of malaria mosquitoes to volatile blends produced by human skin bacteria.

    Science.gov (United States)

    Verhulst, Niels O; Andriessen, Rob; Groenhagen, Ulrike; Bukovinszkiné Kiss, Gabriella; Schulz, Stefan; Takken, Willem; van Loon, Joop J A; Schraa, Gosse; Smallegange, Renate C

    2010-12-30

    The malaria mosquito Anopheles gambiae sensu stricto is mainly guided by human odour components to find its blood host. Skin bacteria play an important role in the production of human body odour and when grown in vitro, skin bacteria produce volatiles that are attractive to A. gambiae. The role of single skin bacterial species in the production of volatiles that mediate the host-seeking behaviour of mosquitoes has remained largely unknown and is the subject of the present study. Headspace samples were taken to identify volatiles that mediate this behaviour. These volatiles could be used as mosquito attractants or repellents. Five commonly occurring species of skin bacteria were tested in an olfactometer for the production of volatiles that attract A. gambiae. Odour blends produced by some bacterial species were more attractive than blends produced by other species. In contrast to odours from the other bacterial species tested, odours produced by Pseudomonas aeruginosa were not attractive to A. gambiae. Headspace analysis of bacterial volatiles in combination with behavioural assays led to the identification of six compounds that elicited a behavioural effect in A. gambiae. Our results provide, to our knowledge, the first evidence for a role of selected bacterial species, common on the human skin, in determining the attractiveness of humans to malaria mosquitoes. This information will be used in the further development of a blend of semiochemicals for the manipulation of mosquito behaviour.

  10. Generation of electrical power under human skin by subdermal solar cell arrays for implantable bioelectronic devices.

    Science.gov (United States)

    Song, Kwangsun; Han, Jung Hyun; Yang, Hyung Chae; Nam, Kwang Il; Lee, Jongho

    2017-06-15

    Medical electronic implants can significantly improve people's health and quality of life. These implants are typically powered by batteries, which usually have a finite lifetime and therefore must be replaced periodically using surgical procedures. Recently, subdermal solar cells that can generate electricity by absorbing light transmitted through skin have been proposed as a sustainable electricity source to power medical electronic implants in bodies. However, the results to date have been obtained with animal models. To apply the technology to human beings, electrical performance should be characterized using human skin covering the subdermal solar cells. In this paper, we present electrical performance results (up to 9.05mW/cm 2 ) of the implantable solar cell array under 59 human skin samples isolated from 10 cadavers. The results indicate that the power densities depend on the thickness and tone of the human skin, e.g., higher power was generated under thinner and brighter skin. The generated power density is high enough to operate currently available medical electronic implants such as pacemakers that require tens of microwatt. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Impact of Humidity on In Vitro Human Skin Permeation Experiments for Predicting In Vivo Permeability.

    Science.gov (United States)

    Ishida, Masahiro; Takeuchi, Hiroyuki; Endo, Hiromi; Yamaguchi, Jun-Ichi

    2015-12-01

    In vitro skin permeation studies have been commonly conducted to predict in vivo permeability for the development of transdermal therapeutic systems (TTSs). We clarified the impact of humidity on in vitro human skin permeation of two TTSs having different breathability and then elucidated the predictability of in vivo permeability based on in vitro experimental data. Nicotinell(®) TTS(®) 20 and Frandol(®) tape 40mg were used as model TTSs in this study. The in vitro human skin permeation experiments were conducted under humidity levels similar to those used in clinical trials (approximately 50%) as well as under higher humidity levels (approximately 95%). The skin permeability values of drugs at 95% humidity were higher than those at 50% humidity. The time profiles of the human plasma concentrations after TTS application fitted well with the clinical data when predicted based on the in vitro permeation parameters at 50% humidity. On the other hand, those profiles predicted based on the parameters at 95% humidity were overestimated. The impact of humidity was higher for the more breathable TTS; Frandol(®) tape 40mg. These results show that in vitro human skin permeation experiments should be investigated under realistic clinical humidity levels especially for breathable TTSs. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  12. [Effect of PRX-2 gene transferred by lipofectamine on the proliferation of human skin fibroblasts].

    Science.gov (United States)

    Song, Hui-feng; Chai, Jia-ke; Lin, Zi-hao

    2011-10-11

    To explore the effects of PRX-2 gene transferred by lipofectamine on the human skin fibroblasts. Normal human skin fibroblasts were cultured and PRX-2 gene was transferred by lipofectamine. The proliferation of fibroblasts was detected by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) and flow cytometry. The proliferation of PRX-2-transfected fibroblasts was stronger than that of normal counterparts. There were fewer cells during G0-G1 period and more cells during S and G2-M periods. The proliferative index increased. The proliferation of fibroblasts may be modified by transfected PRX-2. Thus PRX-2 plays an important role during the healing of human skin wound.

  13. Global Distribution and Variability of Surface Skin and Surface Air Temperatures as Depicted in the AIRS Version-6 Data Set

    Science.gov (United States)

    Susskind, Joel; Lee, Jae N.; Iredell, Lena

    2014-01-01

    In this presentation, we will briefly describe the significant improvements made in the AIRS Version-6 retrieval algorithm, especially as to how they affect retrieved surface skin and surface air temperatures. The global distribution of seasonal 1:30 AM and 1:30 PM local time 12 year climatologies of Ts,a will be presented for the first time. We will also present the spatial distribution of short term 12 year anomaly trends of Ts,a at 1:30 AM and 1:30 PM, as well as the spatial distribution of temporal correlations of Ts,a with the El Nino Index. It will be shown that there are significant differences between the behavior of 1:30 AM and 1:30 PM Ts,a anomalies in some arid land areas.

  14. Mimicking the tribo-mechanical performance of human skin: a scale dependent approach based on poly (vinyl alcohol) hydrogel

    NARCIS (Netherlands)

    Morales Hurtado, Marina

    2016-01-01

    The development of an appropriate substitute to simulate the frictional performance of human skin at different conditions is required for the design and optimization of products in contact with the skin. With this purpose, the composition, structure and mechanical properties of the skin need to be

  15. Date seed oil limit oxidative injuries induced by hydrogen peroxide in human skin organ culture.

    Science.gov (United States)

    Dammak, Ines; Abdallah, Fatma Ben; Boudaya, Sonia; Besbes, Souhail; Keskes, Leila; El Gaied, Amel; Turki, Hamida; Attia, Hammadi; Hentati, Basma

    2007-01-01

    The skin is chronically exposed to pro-oxidant agents, leading to the generation of reactive oxygen species (ROS). To protect the skin against an over-load of oxidant species, we studied the chemoprotective effect of one new natural product: "date seed oil: DSO". This oil may serve as a potential source of natural antioxidants such as phenols and tocopherols. Here, the antioxidative potential of DSO was compared that of to extra virgin olive oil. Adult human skin was maintained in organ culture in the presence of the DSO and extra virgin olive oil before the addition of hydrogen peroxide (H2O2), in order to prevent the tissue from its oxidizing effects. Skin specimens were collected for histology and for melanin studies. In the investigated model system, DSO protects skin against oxidative injuries. It has a significant chemoprotective effect, by inhibition of damage caused by H_{2}O_{2} compared with specimens without such addition endowing with a radical scavenging ability. The various components from DSO were much more potent antioxidant and more free radical scavengers of the H2O2 than those of olive oil. Our study shows that topical DSO treatment of the skin stimulates events in the epidermis leading to repair skin damage possibly due to antioxidant synergisms.

  16. Human facial skin detection in thermal video to effectively measure electrodermal activity (EDA)

    Science.gov (United States)

    Kaur, Balvinder; Hutchinson, J. Andrew; Leonard, Kevin R.; Nelson, Jill K.

    2011-06-01

    In the past, autonomic nervous system response has often been determined through measuring Electrodermal Activity (EDA), sometimes referred to as Skin Conductance (SC). Recent work has shown that high resolution thermal cameras can passively and remotely obtain an analog to EDA by assessing the activation of facial eccrine skin pores. This paper investigates a method to distinguish facial skin from non-skin portions on the face to generate a skin-only Dynamic Mask (DM), validates the DM results, and demonstrates DM performance by removing false pore counts. Moreover, this paper shows results from these techniques using data from 20+ subjects across two different experiments. In the first experiment, subjects were presented with primary screening questions for which some had jeopardy. In the second experiment, subjects experienced standard emotion-eliciting stimuli. The results from using this technique will be shown in relation to data and human perception (ground truth). This paper introduces an automatic end-to-end skin detection approach based on texture feature vectors. In doing so, the paper contributes not only a new capability of tracking facial skin in thermal imagery, but also enhances our capability to provide non-contact, remote, passive, and real-time methods for determining autonomic nervous system responses for medical and security applications.

  17. Human Skin Permeation Studies with PPARγ Agonist to Improve Its Permeability and Efficacy in Inflammatory Processes

    Directory of Open Access Journals (Sweden)

    Marcelle Silva-Abreu

    2017-11-01

    Full Text Available Rosacea is the most common inflammatory skin disease. It is characterized by erythema, inflammatory papules and pustules, visible blood vessels, and telangiectasia. The current treatment has limitations and unsatisfactory results. Pioglitazone (PGZ is an agonist of peroxisome proliferator-activated receptors (PPARs, a nuclear receptor that regulates important cellular functions, including inflammatory responses. The purpose of this study was to evaluate the permeation of PGZ with a selection of penetration enhancers and to analyze its effectiveness for treating rosacea. The high-performance liquid chromatography (HPLC method was validated for the quantitative determination of PGZ. Ex vivo permeation experiments were realized in Franz diffusion cells using human skin, in which PGZ with different penetration enhancers were assayed. The results showed that the limonene was the most effective penetration enhancer that promotes the permeation of PGZ through the skin. The cytotoxicity studies and the Draize test detected cell viability and the absence of skin irritation, respectively. The determination of the skin color using a skin colorimetric probe and the results of histopathological studies confirmed the ability of PGZ-limonene to reduce erythema and vasodilation. This study suggests new pharmacological indications of PGZ and its possible application in the treatment of skin diseases, namely rosacea.

  18. Real-time, High-resolution, In Vivo Characterization of Superficial Skin With Microscopy Using Ultraviolet Surface Excitation (MUSE).

    Science.gov (United States)

    Ho, Derek; Fereidouni, Farzad; Levenson, Richard M; Jagdeo, Jared

    2016-11-01

    Skin care products make up the largest part (36%) of the cosmetic market globally, of which the United States plays the largest role. In 2015, approximately 115 billion USD was spent globally on skin care products. Skin care products, in contradistinction to pharmaceuticals, are not strictly regulated by the FDA. A key factor for evaluation of a skin care product or topical drug is skin barrier function and effect on super cial skin. Thus, it is critical to have quantitative and qualitative methods to study the effects of skin care products on skin barrier and the super cial skin. Currently, no imaging method exists that can evaluate and track super cial skin changes visually in real-time. To report using a novel imaging modality, Microscopy using Ultraviolet Surface Excitation (MUSE), to provide real-time, high- resolution, in vivo characterization of super cial skin and moisturizing properties of topical moisturizer, and to highlight key bene ts of using MUSE to visualize the super cial skin and serve as an excellent complementary tool to current quantitative methods. The methodology of MUSE is based upon two main principles inherent to ultraviolet (UV) light and uorescent staining agents. In this study, the author's (JJ) index ngertip was imaged using the MUSE instrument without and with moisturizer. Dermatoglyphics of the fingertip consists of ridges (cristae super ciales) and grooves (sulci super ciales) proved to be straightforward to visualize at high resolution. Desquamation of superficial corneocytes and opening of an acrosyringium (the most superficial portion of eccrine ducts) were visualized in high-resolution. Post-application of a moisturizer, a uniform layer of moisturizer could be seen superficial to the corneocytes along the ridges and CONCLUSIONS: Real-time, high-resolution, in vivo characterization of super cial skin and moisturizing properties of moisturizer using MUSE is feasible. Its utility can be enhanced with downstream quantification using

  19. Relative Penetration of Zinc Oxide and Zinc Ions into Human Skin after Application of Different Zinc Oxide Formulations.

    Science.gov (United States)

    Holmes, Amy M; Song, Zhen; Moghimi, Hamid R; Roberts, Michael S

    2016-02-23

    Zinc oxide (ZnO) is frequently used in commercial sunscreen formulations to deliver their broad range of UV protection properties. Concern has been raised about the extent to which these ZnO particles (both micronized and nanoparticulate) penetrate the skin and their resultant toxicity. This work has explored the human epidermal skin penetration of zinc oxide and its labile zinc ion dissolution product that may potentially be formed after application of ZnO nanoparticles to human epidermis. Three ZnO nanoparticle formulations were used: a suspension in the oil, capric caprylic triglycerides (CCT), the base formulation commonly used in commercially available sunscreen products; an aqueous ZnO suspension at pH 6, similar to the natural skin surface pH; and an aqueous ZnO suspension at pH 9, a pH at which ZnO is stable and there is minimal pH-induced impairment of epidermal integrity. In each case, the ZnO in the formulations did not penetrate into the intact viable epidermis for any of the formulations but was associated with an enhanced increase in zinc ion fluorescence signal in both the stratum corneum and the viable epidermis. The highest labile zinc fluorescence was found for the ZnO suspension at pH 6. It is concluded that, while topically applied ZnO does not penetrate into the viable epidermis, these applications are associated with hydrolysis of ZnO on the skin surface, leading to an increase in zinc ion levels in the stratum corneum, thence in the viable epidermis and subsequently in the systemic circulation and the urine.

  20. Cigarette smoke toxins deposited on surfaces: implications for human health

    National Research Council Canada - National Science Library

    Martins-Green, Manuela; Adhami, Neema; Frankos, Michael; Valdez, Mathew; Goodwin, Benjamin; Lyubovitsky, Julia; Dhall, Sandeep; Garcia, Monika; Egiebor, Ivie; Martinez, Bethanne; Green, Harry W; Havel, Christopher; Yu, Lisa; Liles, Sandy; Matt, Georg; Destaillats, Hugo; Sleiman, Mohammed; Gundel, Laura A; Benowitz, Neal; Jacob, 3rd, Peyton; Hovell, Melbourne; Winickoff, Jonathan P; Curras-Collazo, Margarita

    2014-01-01

    ... been allowed. The goal of this study is to investigate the effects of THS on liver, lung, skin healing, and behavior, using an animal model exposed to THS under conditions that mimic exposure of humans...

  1. Transdermal kinetics of a mercurous chloride beauty cream: an in vitro human skin analysis.

    Science.gov (United States)

    Palmer, R B; Godwin, D A; McKinney, P E

    2000-01-01

    Crema de Belleza-Manning is a popular mercurous chloride-containing beauty cream used to smooth and lighten the complexion and treat acne. Hundreds of people in the Southwestern US border states have been identified with elevated (>20 microg/L) urine mercury levels believed to be secondary to using this cream. The kinetic characteristics of percutaneous mercury absorption are incompletely defined. The objective of this study was to determine the transdermal kinetics of two formulations of mercurous chloride from a beauty cream in an in vitro human skin model. A proprietary formulation and an aqueous formulation of the beauty cream were studied using modified Franz diffusion cells. Mercury content in the skin samples and the underlying diffusion buffer was determined using atomic absorption spectrophotometry. A rapid initial increase in mercury content both in the skin and the buffer was noted for both formulations. Mercury concentrations in the aqueous samples were significantly (p < 0.05) higher in both the skin and the diffusion buffer compared to parallel samples containing glycerol. Mercury was readily absorbed through the skin in this in vitro human skin model. The aqueous preparation had a markedly increased rate and extent of mercury absorption relative to the proprietary formulation.

  2. The use of nanoencapsulation to decrease human skin irritation caused by capsaicinoids.

    Science.gov (United States)

    Contri, Renata V; Frank, Luiza A; Kaiser, Moacir; Pohlmann, Adriana R; Guterres, Silvia S

    2014-01-01

    Capsaicin, a topical analgesic used in the treatment of chronic pain, has irritant properties that frequently interrupt its use. In this work, the effect of nanoencapsulation of the main capsaicinoids (capsaicin and dihydrocapsaicin) on skin irritation was tested in humans. Skin tolerance of a novel vehicle composed of chitosan hydrogel containing nonloaded nanocapsules (CH-NC) was also evaluated. The chitosan hydrogel containing nanoencapsulated capsaicinoids (CH-NC-CP) did not cause skin irritation, as measured by an erythema probe and on a visual scale, while a formulation containing free capsaicinoids (chitosan gel with hydroalcoholic solution [CH-ET-CP]) and a commercially available capsaicinoids formulation caused skin irritation. Thirty-one percent of volunteers reported slight irritation one hour after application of CH-NC-CP, while moderate (46% [CH-ET-CP] and 23% [commercial product]) and severe (8% [CH-ET-CP] and 69% [commercial product]) irritation were described for the formulations containing free capsaicinoids. When CH-NC was applied to the skin, erythema was not observed and only 8% of volunteers felt slight irritation, which demonstrates the utility of the novel vehicle. A complementary in vitro skin permeation study showed that permeation of capsaicinoids through an epidermal human membrane was reduced but not prevented by nanoencapsulation.

  3. Human skin-color sexual dimorphism: a test of the sexual selection hypothesis.

    Science.gov (United States)

    Madrigal, Lorena; Kelly, William

    2007-03-01

    Applied to skin color, the sexual selection hypothesis proposes that male preference for light-skinned females explains the presence of light skin in areas of low solar radiation. According to this proposal, in areas of high solar radiation, natural selection for dark skin overrides the universal preference of males for light females. But in areas in which natural selection ceases to act, sexual selection becomes more important, and causes human populations to become light-skinned, and females to be lighter than males. The sexual selection hypothesis proposes that human sexual dimorphism of skin color should be positively correlated with distance from the equator. We tested the prediction that sexual dimorphism should increase with increasing latitude, using adult-only data sets derived from measurements with standard reflectance spectrophotometric devices. Our analysis failed to support the prediction of a positive correlation between increasing distance from the equator and increased sexual dimorphism. We found no evidence in support of the sexual selection hypothesis. (c) 2006 Wiley-Liss, Inc.

  4. Pistacia lentiscus fruit oil reduces oxidative stress in human skin explants caused by hydrogen peroxide.

    Science.gov (United States)

    Ben Khedir, S; Moalla, D; Jardak, N; Mzid, M; Sahnoun, Z; Rebai, T

    2016-10-01

    We investigated the efficacy of Pistacia lentiscus fruit oil (PLFO) for protecting human skin from damage due to oxidative stress. PLFO contains natural antioxidants including polyphenols, sterols and tocopherols. We compared the antioxidant potential of PLFO with extra virgin olive oil (EVOO). Explants of healthy adult human skin were grown in culture with either PLFO or EVOO before adding hydrogen peroxide (H2O2). We also used cultured skin explants to investigate the effects of PLFO on lipid oxidation and depletion of endogenous antioxidant defense enzymes including glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) one day after 2 h exposure to H2O2. We found that PLFO scavenged radicals and protected skin against oxidative injury. PLFO exhibited greater antioxidant and free radical scavenging activity than EVOO. Skin explants treated with PLFO inhibited H2O2 induced MDA formation by inhibition of lipid oxidation. In addition, the oil inhibited H2O2 induced depletion of antioxidant defense enzymes including GPx, SOD and CAT. We found that treatment with PLFO repaired skin damage owing to its antioxidant properties.

  5. Direct 3D cell-printing of human skin with functional transwell system.

    Science.gov (United States)

    Kim, Byoung Soo; Lee, Jung-Seob; Gao, Ge; Cho, Dong-Woo

    2017-06-06

    Three-dimensional (3D) cell-printing has been emerging as a promising technology with which to build up human skin models by enabling rapid and versatile design. Despite the technological advances, challenges remain in the development of fully functional models that recapitulate complexities in the native tissue. Moreover, although several approaches have been explored for the development of biomimetic human skin models, the present skin models based on multistep fabrication methods using polydimethylsiloxane chips and commercial transwell inserts could be tackled by leveraging 3D cell-printing technology. In this paper, we present a new 3D cell-printing strategy for engineering a 3D human skin model with a functional transwell system in a single-step process. A hybrid 3D cell-printing system was developed, allowing for the use of extrusion and inkjet modules at the same time. We began by revealing the significance of each module in engineering human skin models; by using the extrusion-dispensing module, we engineered a collagen-based construct with polycaprolactone (PCL) mesh that prevented the contraction of collagen during tissue maturation; the inkjet-based dispensing module was used to uniformly distribute keratinocytes. Taking these features together, we engineered a human skin model with a functional transwell system; the transwell system and fibroblast-populated dermis were consecutively fabricated by using the extrusion modules. Following this process, keratinocytes were uniformly distributed onto the engineered dermis by the inkjet module. Our transwell system indicates a supportive 3D construct composed of PCL, enabling the maturation of a skin model without the aid of commercial transwell inserts. This skin model revealed favorable biological characteristics that included a stabilized fibroblast-stretched dermis and stratified epidermis layers after 14 days. It was also observed that a 50 times reduction in cost was achieved and 10 times less medium was

  6. A role for human mitochondrial complex II in the production of reactive oxygen species in human skin

    Directory of Open Access Journals (Sweden)

    Alasdair Anderson

    2014-01-01

    Full Text Available The mitochondrial respiratory chain is a major generator of cellular oxidative stress, thought to be an underlying cause of the carcinogenic and ageing process in many tissues including skin. Previous studies of the relative contributions of the respiratory chain (RC complexes I, II and III towards production of reactive oxygen species (ROS have focussed on rat tissues and certainly not on human skin which is surprising as this tissue is regularly exposed to UVA in sunlight, a potent generator of cellular oxidative stress. In a novel approach we have used an array of established specific metabolic inhibitors and DHR123 fluorescence to study the relative roles of the mitochondrial RC complexes in cellular ROS production in 2 types of human skin cells. These include additional enhancement of ROS production by exposure to physiological levels of UVA. The effects within epidermal and dermal derived skin cells are compared to other tissue cell types as well as those harbouring a compromised mitochondrial status (Rho-zero A549. The results show that the complex II inhibitor, TTFA, was the only RC inhibitor to significantly increase UVA-induced ROS production in both skin cell types (P<0.05 suggesting that the role of human skin complex II in terms of influencing ROS production is more important than previously thought particularly in comparison to liver cells. Interestingly, two-fold greater maximal activity of complex II enzyme was observed in both skin cell types compared to liver (P<0.001. The activities of RC enzymes appear to decrease with increasing age and telomere length is correlated with ageing. Our study showed that the level of maximal complex II activity was higher in the MRC5/hTERT (human lung fibroblasts transfected with telomerase cells than the corresponding wild type cells (P=0.0012 which can be considered (in terms of telomerase activity as models of younger and older cells respectively.

  7. Biological Activity of Polynesian Calophyllum inophyllum Oil Extract on Human Skin Cells.

    Science.gov (United States)

    Ansel, Jean-Luc; Lupo, Elise; Mijouin, Lily; Guillot, Samuel; Butaud, Jean-François; Ho, Raimana; Lecellier, Gaël; Raharivelomanana, Phila; Pichon, Chantal

    2016-07-01

    Oil from the nuts of Calophyllum inophyllum, locally called "Tamanu oil" in French Polynesia, was traditionally used for wound healing and to cure various skin problems and ailments. The skin-active effect of "Tamanu oil emulsion" was investigated on human skin cells (keratinocytes and dermal fibroblasts) and showed cell proliferation, glycosaminoglycan and collagen production, and wound healing activity. Transcriptomic analysis of the treated cells revealed gene expression modulation including genes involved in the metabolic process implied in O-glycan biosynthesis, cell adhesion, and cell proliferation. The presence of neoflavonoids as bioactive constituents in Tamanu oil emulsion may contribute to these biological activities. Altogether, consistent data related to targeted histological and cellular functions brought new highlights on the mechanisms involved in these biological processes induced by Tamanu oil effects in skin cells. Georg Thieme Verlag KG Stuttgart · New York.

  8. Casting of microstructured shark skin surfaces and possible applications on aluminum casting parts

    Directory of Open Access Journals (Sweden)

    Todor Ivanov

    2011-02-01

    Full Text Available Within the project Functional Surfaces via Micro- and Nanoscaled Structures?which is part of the Cluster of Excellence 揑ntegrative Production Technology?established and financed by the German Research Foundation (DFG, an investment casting process to produce 3-dimensional functional surfaces down to a structural size of 1 μm on near-net-shape-casting parts has been developed. The common way to realize functional microstructures on metallic surfaces is to use laser ablation, electro discharge machining or micro milling. The handicap of these processes is their limited productivity. The approach of this project to raise the efficiency is to use the investment casting process to replicate microstructured surfaces by moulding from a laser-microstructured grand master pattern. The main research objective deals with the investigation of the single process steps of the investment casting process with regard to the moulding accuracy. Actual results concerning making of the wax pattern, suitability of ceramic mould and core materials for casting of an AlSi7Mg0.3 alloy as well as the knock-out behavior of the shells are presented. By using of the example of an intake manifold of a gasoline race car engine, a technical shark skin surface has been realized to reduce the drag of the intake air. The intake manifold consists of an air-restrictor with a defined inner diameter which is microstructured with technical shark skin riblets. For this reason the inner diameter cannot be drilled after casting and demands a very high accuracy of the casting part. A technology for the fabrication and demoulding of accurate microstructured castings are shown. Shrinkage factors of different moulding steps of the macroscopic casting part as well as the microscopic riblet structure have been examined as well.

  9. Blood-group-related carbohydrates are expressed in organotypic cultures of human skin and oral mucosa

    DEFF Research Database (Denmark)

    Grøn, B; Andersson, A; Dabelsteen, Erik

    1999-01-01

    the function of cell-surface carbohydrates, we established organotypic cultures of skin and buccal mucosa. In these cultures, keratinocytes are grown at the air-liquid interface on a supporting matrix consisting of homologous fibroblasts embedded in a collagen type I gel. We examined the expression of blood...... cultures. The organotypic skin and oral mucosa cultures showed a histological differentiation pattern analogous to that of normal skin and buccal mucosa, and a tissue-specific expression of carbohydrate structures and cytokeratins. However, both types of organotypic cultures also expressed markers which......Cellular maturation and migration are usually associated with changes in cell-surface carbohydrates, but the relationship between these changes and cell behaviour is at present largely unknown. To investigate whether an organotypic culture system can be used as an in vitro model to study...

  10. Ethosomes for skin delivery of ammonium glycyrrhizinate: in vitro percutaneous permeation through human skin and in vivo anti-inflammatory activity on human volunteers.

    Science.gov (United States)

    Paolino, Donatella; Lucania, Giuseppe; Mardente, Domenico; Alhaique, Franco; Fresta, Massimo

    2005-08-18

    The aim of this work was the evaluation of various ethosomal suspensions made up of water, phospholipids and ethanol at various concentrations for their potential application in dermal administration of ammonium glycyrrhizinate, a useful drug for the treatment of various inflammatory-based skin diseases. Physicochemical characterization of ethosomes was carried out by photon correlation spectroscopy and freeze fracture electron microscopy. The percutaneous permeation of ammonium glycyrrhizinate/ethosomes was evaluated in vitro through human stratum corneum and epidermis membranes by using Franz's cells and compared with the permeation profiles of drug solutions either in water or in a water-ethanol mixture. Reflectance spectrophotometry was used as a non-invasive technique to evaluate the carrier toxicity, the drug permeation and the anti-inflammatory activity of ammonium glycyrrhizinate in a model of skin erythema in vivo on human volunteers. Ethosomal suspensions had mean sizes ranging from 350 nm to 100 nm as a function of ethanol and lecithin quantities, i.e., high amounts of ethanol and a low lecithin concentration provided ethosome suspensions with a mean size of approximately 100 nm and a narrow size distribution. In vitro and in vivo experiments were carried out by using an ethosome formulation made up of ethanol 45% (v/v) and lecithin 2% (w/v). The ethosome suspension showed a very good skin tolerability in human volunteers, also when applied for a long period (48 h). Ethosomes elicited an increase of the in vitro percutaneous permeation of both methylnicotinate and ammonium glycyrrhizinate. Ethosomes were able to significantly enhance the anti-inflammatory activity of ammonium glycyrrhizinate compared to the ethanolic or aqueous solutions of this drug. Some in vivo experiments also showed the ability of ethosome to ensure a skin accumulation and a sustained release of the ammonium glycyrrhizinate.

  11. Effects of cigarette smoke residues from textiles on fibroblasts, neurocytes and zebrafish embryos and nicotine permeation through human skin.

    Science.gov (United States)

    Hammer, Timo R; Fischer, Kirsten; Mueller, Marina; Hoefer, Dirk

    2011-09-01

    Toxic substances from cigarette smoke can attach to carpets, curtains, clothes or other surfaces and thus may pose risks to affected persons. The phenomenon itself and the potential hazards are discussed controversially, but scientific data are rare. The objective of this study was to examine the potential of textile-bound nicotine for permeation through human skin and to assess the effects of cigarette smoke extracts from clothes on fibroblasts, neurocytes and zebrafish embryos. Tritiated nicotine from contaminated cotton textiles penetrated through adult human full-thickness skin as well as through a 3D in vitro skin model in diffusion chambers. We also observed a significant concentration-dependent cytotoxicity of textile smoke extracts on fibroblast viability and structure as well as on neurocytes. Early larval tests with zebrafish embryos were used as a valid assay for testing acute vertebrate toxicity. Zebrafish development was delayed and most of the embryos died when exposed to smoke extracts from textiles. Our data show that textiles contaminated with cigarette smoke represent a potential source of nicotine uptake and can provoke adverse health effects. Copyright © 2011 Elsevier GmbH. All rights reserved.

  12. In Vivo Human Skin Penetration Study of Sunscreens by Confocal Raman Spectroscopy.

    Science.gov (United States)

    Tippavajhala, Vamshi Krishna; de Oliveira Mendes, Thiago; Martin, Airton Abrahão

    2017-10-05

    This research work mainly deals with the application of confocal Raman spectroscopic technique to study in vivo human skin penetration of sunscreen products, as there are a lot of controversies associated with their skin penetration. Healthy human volunteers were tested for penetration of two commercial sunscreen products into their volar forearm skin for a period of 2 h. Measurements were taken before and after application of these sunscreen products. All the confocal Raman spectra were pre-processed and then subjected to multivariate two-dimensional principal component analysis and classical least squares analysis to determine the skin penetration of these sunscreens in comparison to the "sunscreen product spectrum" which was considered as the control. Score plots of principal component analysis of confocal Raman spectra indicated clear separation between the spectra before and after application of sunscreen products. Loading plots showed the maximum differences in the spectral region from 1590 to 1626 cm(-1) where the characteristic peak of the pure sunscreen products was observed. Classical least squares analysis has shown a significant penetration to a depth of 10 μm in the volar forearm skin of healthy human volunteers for both these sunscreen products. The results confirm that the penetration of these tested sunscreen products was restricted to stratum corneum and also prove that confocal Raman spectroscopy is a simple, fast, nondestructive, and noninvasive semi-quantitative analytical technique for these studies.

  13. Wood-mimetic skins prepared using horseradish peroxidase catalysis to induce surface wrinkling of chitosan film upon drying.

    Science.gov (United States)

    Izawa, Hironori; Dote, Yuki; Okuda, Noriko; Sumita, Masato; Ifuku, Shinsuke; Morimoto, Minoru; Saimoto, Hiroyuki

    2017-10-01

    We previously developed bio-based wrinkled surfaces induced by wood-mimetic skins upon drying in which microscopic wrinkles were fabricated on a chitosan (CS) film by immersing it in a phenolic acid solution, followed by horseradish peroxidase (HRP)-catalyzed surface reaction and drying. However, the detailed structure of the resulting wood-mimetic skins, including crosslinking mode and thickness, has not been clarified due to the difficulty of the analysis. Here, we prepare wrinkled films using ferulic acid (FE), vanillic acid (VA), and homovanillic acid (HO) and characterize their structures to clarify the unknown characteristics of wood-mimetic skin. Chemical and structural analyses of wood-mimetic skins prepared using VA and HO indicate that the crosslinking structure in the skin is composed of ionic bonds between CS and an oligophenolic residue generated by the HRP-catalyzed reaction on the CS surface. Moreover, the quantity of these ionic bonds is related to the skin hardness and wrinkle size. Finally, SEM and TOF-SIMS analyses indicate that the skin thickness is on the submicron order (<200nm). Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Tenskinmetric Evaluation of Surface Energy Changes in Adult Skin: Evidence from 834 Normal Subjects Monitored in Controlled Conditions

    Directory of Open Access Journals (Sweden)

    Camilla Dal Bosco

    2014-03-01

    Full Text Available To evaluate the influence of the skin aging critical level on the adult skin epidermal functional state, an improved analytical method based on the skin surface energetic measurement (TVS modeling was developed. Tenskinmetric measurements were carried out non-invasively in controlled conditions by contact angle method using only a water-drop as reference standard liquid. Adult skin was monitored by TVS Observatory according to a specific and controlled thermal protocol (Camianta protocol in use at the interconnected “Mamma Margherita Terme spa” of Terme Euganee. From June to November 2013, the surface free energy and the epidermal hydration level of adult skin were evaluated on arrival of 265 male and 569 female adult volunteers (51–90 years of age and when they departed 2 weeks later. Sensitive measurements were carried out at 0.1 mN/m. High test compliance was obtained (93.2% of all guests. Very interesting results are obtained. The high sensitivity and discrimination power of tenskinmetry combined with a thermal Camianta protocol demonstrate the possibility to evaluate at baseline level the surface energetic changes and the skin reactivity which occurs on adult skin.

  15. Influence of Chemotherapy on the Antioxidant Status of Human Skin.

    Science.gov (United States)

    Lee, Bich Na; Jung, Sora; Darvin, Maxim E; Eucker, Jan; Kühnhardt, Dagmar; Sehouli, Jalid; Chekerov, Radoslav; Patzelt, Alexa; Fuss, Harald; Yu, Ruo-Xi; Lademann, Jürgen

    2016-08-01

    Palmoplantar erythrodysesthesia is a frequent dermal side-effect during chemotherapy. Previous investigations showed radical formation subsequent to doxorubicin infusion and preventative and therapeutic effects of an antioxidant-containing ointment. Using a non-invasive vivomeasuring system (Biozoom®; Biozoom Services GmbH, Kassel, Germany) changes in the antioxidant status (as measured by relative carotenoid concentration) of the skin prior to and after intravenous administration of paclitaxel, docetaxel and 5-fluorouracil were investigated in 42 patients with cancer. A significant decrease of antioxidant concentration subsequent to intravenous administration was found for all investigated chemotherapeutic agents. The mean concentration of carotenoids decreased from 3.59±1.26 arbitrary units (a.u.) to 3.41±1.28 a.u. (p<0.001) after paclitaxel administration, from 6.33±2.43 to 5.63±2.29 a.u. after docetaxel (p=0.027) and from 4.26±1.81 to 3.98±1.53 a.u. (p=0.042) after 5-fluorouracil infusion. Oxidative stress might play a significant role in the pathomechanism of palmoplantar erythrodysesthesia associated with paclitaxel, docetaxel and 5-fluorouracil. Therefore, an antioxidant-containing ointment might serve as preventative and therapeutic option. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  16. Clinical Nonlinear Laser Imaging of Human Skin: A Review

    Directory of Open Access Journals (Sweden)

    Riccardo Cicchi

    2014-01-01

    Full Text Available Nonlinear optical microscopy has the potential of being used in vivo as a noninvasive imaging modality for both epidermal and dermal imaging. This paper reviews the capabilities of nonlinear microscopy as a noninvasive high-resolution tool for clinical skin inspection. In particular, we show that two-photon fluorescence microscopy can be used as a diagnostic tool for characterizing epidermal layers by means of a morphological examination. Additional functional information on the metabolic state of cells can be provided by measuring the fluorescence decay of NADH. This approach allows differentiating epidermal layers having different structural and cytological features and has the potential of diagnosing pathologies in a very early stage. Regarding therapy follow-up, we demonstrate that nonlinear microscopy could be successfully used for monitoring the effect of a treatment. In particular, combined two-photon fluorescence and second-harmonic generation microscopy were used in vivo for monitoring collagen remodeling after microablative fractional laser resurfacing and for quantitatively monitoring psoriasis on the basis of the morphology of epidermal cells and dermal papillae. We believe that the described microscopic modalities could find in the near future a stable place in a clinical dermatological setting for quantitative diagnostic purposes and as a monitoring method for various treatments.

  17. Permeability of commercial solvents through living human skin

    DEFF Research Database (Denmark)

    Ursin, C; Hansen, C M; Van Dyk, J W

    1995-01-01

    was characterized by calculation of the "percent error of the slope." The following permeability rates (g/m2h) of single solvents were measured: dimethyl sulfoxide (DMSO), 176; N-methyl-2-pyrrolidone, 171; dimethyl acetamide, 107; methyl ethyl ketone, 53; methylene chloride, 24; [3H]water, 14.8; ethanol, 11.......3; butyl acetate, 1.6; gamma-butyrolactone, 1.1; toluene, 0.8; propylene carbonate, 0.7; and sulfolane, 0.2. The effect of [3H]water saturation on the shape of the presteady state portion of the permeation curve was determined and found to be very dependent on the solvent. The permeability of mixtures...... of DMSO and octyl acetate were measured. No octyl acetate was detected and the permeability of DMSO was proportional to its mole fraction in the mixture. The effect of two hours of solvent exposure on the viability of skin (based on DNA synthesis) was measured and found to be very dependent on the solvent....

  18. Cigarette smoke toxins deposited on surfaces: implications for human health.

    Directory of Open Access Journals (Sweden)

    Manuela Martins-Green

    Full Text Available Cigarette smoking remains a significant health threat for smokers and nonsmokers alike. Secondhand smoke (SHS is intrinsically more toxic than directly inhaled smoke. Recently, a new threat has been discovered - Thirdhand smoke (THS - the accumulation of SHS on surfaces that ages with time, becoming progressively more toxic. THS is a potential health threat to children, spouses of smokers and workers in environments where smoking is or has been allowed. The goal of this study is to investigate the effects of THS on liver, lung, skin healing, and behavior, using an animal model exposed to THS under conditions that mimic exposure of humans. THS-exposed mice show alterations in multiple organ systems and excrete levels of NNAL (a tobacco-specific carcinogen biomarker similar to those found in children exposed to SHS (and consequently to THS. In liver, THS leads to increased lipid levels and non-alcoholic fatty liver disease, a precursor to cirrhosis and cancer and a potential contributor to cardiovascular disease. In lung, THS stimulates excess collagen production and high levels of inflammatory cytokines, suggesting propensity for fibrosis with implications for inflammation-induced diseases such as chronic obstructive pulmonary disease and asthma. In wounded skin, healing in THS-exposed mice has many characteristics of the poor healing of surgical incisions observed in human smokers. Lastly, behavioral tests show that THS-exposed mice become hyperactive. The latter data, combined with emerging associated behavioral problems in children exposed to SHS/THS, suggest that, with prolonged exposure, they may be at significant risk for developing more severe neurological disorders. These results provide a basis for studies on the toxic effects of THS in humans and inform potential regulatory policies to prevent involuntary exposure to THS.

  19. Chronological age affects the permeation of fentanyl through human skin in vitro

    DEFF Research Database (Denmark)

    Holmgaard, R; Benfeldt, E; Sorensen, J A

    2013-01-01

    AIM: To study the influence of chronological age on fentanyl permeation through human skin in vitro using static diffusion cells. Elderly individuals are known to be more sensitive to opioids and obtain higher plasma concentrations following dermal application of fentanyl compared to younger...... individuals. The influence of age - as an isolated pharmacokinetic term - on the absorption of fentanyl has not been previously studied. METHOD: Human skin from 30 female donors was mounted in static diffusion cells, and samples were collected during 48 h. Donors were divided into three age groups: ... and old age groups: 5,922 and 4,050 ng, respectively). Furthermore, the lag time and absorption rate were different between the three groups, with a significantly higher rate in the young participants versus the oldest participants. CONCLUSION: We demonstrate that fentanyl permeates the skin of young...

  20. Surfactant-induced dermatitis: comparison of corneosurfametry with predictive testing on human and reconstructed skin.

    Science.gov (United States)

    Piérard, G E; Goffin, V; Hermanns-Lê, T; Arrese, J E; Piérard-Franchimont, C

    1995-09-01

    Surfactants elicit alterations in the stratum corneum. Predictive tests that avoid animal experimentation are needed. This study compares three methods of rating and predicting shampoo-induced irritation. Corneosurfametry entails collection of stratum corneum followed by brief contact with diluted surfactants and measurement of variations in staining of samples. Corneosurfametry appears to correlate well with in vivo testing in volunteers with sensitive skin. However, corneosurfametry presents less interindividual variability than in vivo testing and allows better discrimination among mild products. Morphologic information about surfactant-induced loosening of corneocytes may be increased by testing surfactants on human skin equivalent. Results are similar to those provided by specimens used for corneosurfametry. The corneosurfametric prediction of surfactant irritancy correlates with in vivo testing and with in vitro evaluation on human skin equivalent.

  1. A comprehensive comparison between satellite-measured skin and multichannel sea surface temperature

    Science.gov (United States)

    Wick, Gary A.; Emery, William J.; Schluessel, Peter

    1992-01-01

    Three algorithms for computing sea-surface temperature (SST) from AVHRR channel-4 and -5 brightness temperatures were compared using 1-week blocks of global-area-coverage (GAC) data archived at NCAR. These are the multichannel SST (MCSST), the cross-product SST (CPSST), and the AVHRR-only satellite-measured ocean-surface skin temperature (SMSST). Maps of each SST product were produced and were compared for various time periods. The difference between the algorithms range from +1.6 to -1.2 K, resulting from the different forms of both the algorithms and the ground truth from which the algorithms were derived. It is concluded that, for the study of relative SST patterns, any of the algorithms can be used. However, for applications requiring accurate absolute temperature measurements, the differences are significant and the derivation of the algorithm must be considered when an algorithm is selected.

  2. Locomotion of human skin keratinocytes on polystyrene, fibrin, and collagen substrata and its modification by cell-to-cell contacts.

    Science.gov (United States)

    Drukała, J; Bandura, L; Cieślik, K; Korohoda, W

    2001-01-01

    Epithelial wound repair assures the recovery of the epithelial barrier after wounding. During wound healing epithelial cells migrate to cover the wound surface. The presented experiments were carried out to compare the migration of human keratinocytes from primary and secondary culture on polystyrene, collagen, and fibrin glue used in clinical techniques. The images of migrating keratinocytes were recorded and analyzed using computer-aided methods. The results show that the character of the substrate strongly affects the speed and turning behavior of keratinocytes locomoting over it. The highest motile activity of human skin keratinocytes was found on fibrin glue substratum. It was found that locomotion of freely moving isolated cells was much faster than that of cell sheets. The autologous keratinocytes cultured in vitro were applied with fibrin glue to cover trophic wounds. The transplantation of human autologous keratinocyte suspension in fibrin glue upon long-lasting trophic wounds appeared to induce rapid and permanent wound healing.

  3. Surface mold brachytherapy for nonmelanoma skin cancer: Canadian patterns of practice.

    Science.gov (United States)

    Rose, Jim N; McLaughlin, Pierre-Yves; Hanna, Timothy P; D'Souza, David; Sur, Ranjan; Falkson, Conrad B

    2014-01-01

    We sought to describe the use of surface mold brachytherapy (SMBT) for nonmelanoma skin cancer in Canada. A list of Canadian Association of Radiation Oncologists membership and provincial registries were used for a preliminary survey to identify radiation oncologists and physicists involved in the practice of SMBT. A detailed survey was sent electronically to individuals involved in treating with SMBT. Of 41 centers in Canada, 39 responded, with 7 centers indicating use of SMBT. Seven radiation oncologists and 5 physicists from 6 of 7 treating centers responded to the detailed survey, with an overall 75% individual response rate (12/16). General agreement was found regarding indications for SMBT which included irregular or curved surfaces, avoidance of deep structures, and requirement for small fields. There was consensus regarding some contraindications for SMBT such as tumor depth and size. Hypofractionated schedules were used in 5 of 6 centers and doses ranged from 50 Gy in 5 fractions once per week to 30 Gy in 10 fractions twice a day over 5 days. The most common dosimetric parameters for plan evaluation included D90, D95, D100, and maximum skin dose. A minority of Canadian centers practice SMBT. In centers practicing SMBT, general agreement exists on general indications for its use. Given the wide variation in dose and fractionation used and the rarity of the indication a phase 2 Canadian protocol would be invaluable.

  4. Heat loss through the glabrous skin surfaces of heavily insulated, heat-stressed individuals.

    Science.gov (United States)

    Grahn, D A; Dillon, J L; Heller, H C

    2009-07-01

    Insulation reduces heat exchange between a body and the environment. Glabrous (nonhairy) skin surfaces (palms of the hands, soles of the feet, face, and ears) constitute a small percentage of total body surface area but contain specialized vascular structures that facilitate heat loss. We have previously reported that cooling the glabrous skin surfaces is effective in alleviating heat stress and that the application of local subatmospheric pressure enhances the effect. In this paper, we compare the effects of cooling multiple glabrous skin surfaces with and without vacuum on thermal recovery in heavily insulated heat-stressed individuals. Esophageal temperatures (T(es)) and heart rates were monitored throughout the trials. Water loss was determined from pre- and post-trial nude weights. Treadmill exercise (5.6 km/h, 9-16% slope, and 25-45 min duration) in a hot environment (41.5 degrees C, 20-30% relative humidity) while wearing insulating pants and jackets was used to induce heat stress (T(es)>or=39 degrees C). For postexercise recovery, the subjects donned additional insulation (a balaclava, winter gloves, and impermeable boot covers) and rested in the hot environment for 60 min. Postexercise cooling treatments included control (no cooling) or the application of a 10 degrees C closed water circulating system to (a) the hand(s) with or without application of a local subatmospheric pressure, (b) the face, (c) the feet, or (d) multiple glabrous skin regions. Following exercise induction of heat stress in heavily insulated subjects, the rate of recovery of T(es) was 0.4+/-0.2 degrees C/h(n=12), but with application of cooling to one hand, the rate was 0.8+/-0.3 degrees C/h(n=12), and with one hand cooling with subatmospheric pressure, the rate was 1.0+/-0.2 degrees C/h(n=12). Cooling alone yielded two responses, one resembling that of cooling with subatmospheric pressure (n=8) and one resembling that of no cooling (n=4). The effect of treating multiple surfaces was

  5. In vitro differentiation of human skin-derived multipotent stromal cells into putative endothelial-like cells

    Directory of Open Access Journals (Sweden)

    Vishnubalaji Radhakrishnan

    2012-01-01

    Full Text Available Abstract Background Multipotent stem cells have been successfully isolated from various tissues and are currently utilized for tissue-engineering and cell-based therapies. Among the many sources, skin has recently emerged as an attractive source for multipotent cells because of its abundance. Recent literature showed that skin stromal cells (SSCs possess mesoderm lineage differentiation potential; however, the endothelial differentiation and angiogenic potential of SSC remains elusive. In our study, SSCs were isolated from human neonatal foreskin (hNFSSCs and adult dermal skin (hADSSCs using explants cultures and were compared with bone marrow (hMSC-TERT and adipose tissue-derived mesenchymal stem cells (hADMSCs for their potential differentiation into osteoblasts, adipocytes, and endothelial cells. Results Concordant with previous studies, both MSCs and SSCs showed similar morphology, surface protein expression, and were able to differentiate into osteoblasts and adipocytes. Using an endothelial induction culture system combined with an in vitro matrigel angiogenesis assay, hNFSSCs and hADSSCs exhibited the highest tube-forming capability, which was similar to those formed by human umbilical vein endothelial cells (HUVEC, with hNFSSCs forming the most tightly packed, longest, and largest diameter tubules among the three cell types. CD146 was highly expressed on hNFSSCs and HUVEC followed by hADSSCs, and hMSC-TERT, while its expression was almost absent on hADMSCs. Similarly, higher vascular density (based on the expression of CD31, CD34, vWF, CD146 and SMA was observed in neonatal skin, followed by adult dermal skin and adipose tissue. Thus, our preliminary data indicated a plausible relationship between vascular densities, and the expression of CD146 on multipotent cells derived from those tissues. Conclusions Our data is the first to demonstrate that human dermal skin stromal cells can be differentiated into endothelial lineage. Hence, SSCs

  6. Biophysics of skin and its treatments structural, nanotribological, and nanomechanical studies

    CERN Document Server

    Bhushan, Bharat

    2017-01-01

    This book provides a comprehensive overview of the structural, nanotribological and nanomechanical properties of skin with and without cream treatment as a function of operating environment. The biophysics of skin as the outer layer covering human or animal body is discussed as a complex biological structure. Skin cream is used to improve skin health and create a smooth, soft, and flexible surface with moist perception by altering the surface roughness, friction, adhesion, elastic modulus, and surface charge of the skin surface. .

  7. Measurement of the force–displacement response of in vivo human skin under a rich set of deformations

    KAUST Repository

    Flynn, Cormac

    2011-06-01

    The non-linear, anisotropic, and viscoelastic properties of human skin vary according to location on the body, age, and individual. The measurement of skin\\'s mechanical properties is important in several fields including medicine, cosmetics, and forensics. In this study, a novel force-sensitive micro-robot applied a rich set of three-dimensional deformations to the skin surface of different areas of the arms of 20 volunteers. The force-displacement response of each area in different directions was measured. All tested areas exhibited a non-linear, viscoelastic, and anisotropic force-displacement response. There was a wide quantitative variation in the stiffness of the response. For the right anterior forearm, the ratio of the maximum probe reaction force to maximum probe displacement ranged from 0.44Nmm-1 to 1.45Nmm-1. All volunteers exhibited similar qualitative anisotropic characteristics. For the anterior right forearm, the stiffest force-displacement response was when the probe displaced along the longitudinal axis of the forearm. The response of the anterior left forearm was stiffest in a direction 20° to the longitudinal axis of the forearm. The posterior upper arm was stiffest in a direction 90° to the longitudinal axis of the arm. The averaged posterior upper arm response was less stiff than the averaged anterior forearm response. The maximum probe force at 1.3mm probe displacement was 0.69N for the posterior upper arm and 1.1N for the right anterior forearm. The average energy loss during the loading-unloading cycle ranged from 11.9% to 34.2%. This data will be very useful for studying the non-linear, anisotropic, and viscoelastic behaviour of skin and also for generating material parameters for appropriate constitutive models. © 2011 IPEM.

  8. Transgenic expression of human cytoxic T-lymphocyte associated antigen4-immunoglobulin (hCTLA4Ig) by porcine skin for xenogeneic skin grafting.

    Science.gov (United States)

    Wang, Yong; Yang, Hua-Qiang; Jiang, Wen; Fan, Na-Na; Zhao, Ben-Tian; Ou-Yang, Zhen; Liu, Zhao-Ming; Zhao, Yu; Yang, Dong-Shan; Zhou, Xiao-Yang; Shang, Hai-Tao; Wang, Lu-Lu; Xiang, Peng-Ying; Ge, Liang-Peng; Wei, Hong; Lai, Liang-Xue

    2015-04-01

    Porcine skin is frequently used as a substitute of human skin to cover large wounds in clinic practice of wound care. In our previous work, we found that transgenic expression of human cytoxicT-lymphocyte associated antigen4-immunoglobulin (hCTLA4Ig) in murine skin graft remarkably prolonged its survival in xenogeneic wounds without extensive immunosuppression in recipients, suggesting that transgenic hCTLA4Ig expression in skin graft may be an effective and safe method to prolong xenogeneic skin graft survival. In this work, using a transgene construct containing hCTLA4Ig coding sequence under the drive of human Keratine 14 (k14) promoter, hCTLA4Ig transgenic pigs were generated by somatic nuclear transfer. The derived transgenic pigs were healthy and exhibited no signs of susceptibility to infection. The hCTLA4Ig transgene was stably transmitted through germline over generations, and thereby a transgenic pig colony was established. In the derived transgenic pigs, hCTLA4Ig expression in skin was shown to be genetically stable over generations, and detected in heart, kidney and corneal as well as in skin. Transgenic hCTLA4Ig protein in pigs exhibited expected biological activity as it suppressed human lymphocyte proliferation in human mixed lymphocyte culture to extents comparable to those of commercially purchased purified hCTLA4Ig protein. In skin grafting from pigs to rats, transgenic porcine skin grafts exhibited remarkably prolonged survival compared to the wild-type skin grafts derived from the same pig strain (13.33 ± 3.64 vs. 6.25 ± 2.49 days, P porcine skin graft survival in xenogeneic wounds. The transgenic pigs generated in this work can be used as a reproducible resource to provide porcine skin grafts with extended survival for wound coverage, and also as donors to investigate the impacts of hCTLA4Ig on xenotransplantation of other organs (heart, kidney and corneal) due to the ectopic transgenic hCTLA4Ig expression.

  9. In vivo measurements of human neck skin elasticity using MRI and finite element modeling.

    Science.gov (United States)

    An, Yunqiang; Ji, Changjin; Li, Yong; Wang, Jianxia; Zhang, Xinyue; Huang, Yaqi

    2017-04-01

    The assessment of mechanical properties of the human skin is very important in investigating the mechanism of obstructive sleep apnea, a common disorder characterized by repetitive collapse and obstruction of the upper airway during sleep. In this study, a unique method, combining magnetic resonance imaging (MRI) and finite element modeling (FEM), was developed to obtain the value of the in vivo elastic modulus of the neck skin. A total of 22 subjects, 16 males and six females, were recruited to participate in the MRI studies. The changes in the airway and the neck size resulting from fluid shift from the lower body to the neck were measured based on the MR images. A two-dimensional plane strain FE model was built to simulate such changes in the neck cross-section for each subject. Solving an inverse problem using FEM by matching the measured data, we obtained the in vivo elastic modulus of the neck skin to be 1.78 ± 1.73 MPa. Results showed that the elastic modulus tended to increase with age and body mass index for these subjects. A sensitivity analysis of the muscle and fat mechanical parameters was also performed to test their effects on the predicted skin elasticity. The unique method developed in this study for measuring the in vivo elastic modulus of the neck skin is quite effective, and the skin elasticity value obtained using this method is credible. © 2017 American Association of Physicists in Medicine.

  10. Primary Cilia Negatively Regulate Melanogenesis in Melanocytes and Pigmentation in a Human Skin Model.

    Directory of Open Access Journals (Sweden)

    Hyunjung Choi

    Full Text Available The primary cilium is an organelle protruding from the cell body that senses external stimuli including chemical, mechanical, light, osmotic, fluid flow, and gravitational signals. Skin is always exposed to the external environment and responds to external stimuli. Therefore, it is possible that primary cilia have an important role in skin. Ciliogenesis was reported to be involved in developmental processes in skin, such as keratinocyte differentiation and hair formation. However, the relation between skin pigmentation and primary cilia is largely unknown. Here, we observed that increased melanogenesis in melanocytes treated with a melanogenic inducer was inhibited by a ciliogenesis inducer, cytochalasin D, and serum-free culture. However, these inhibitory effects disappeared in GLI2 knockdown cells. In addition, activation of sonic hedgehog (SHH-smoothened (Smo signaling pathway by a Smo agonist, SAG inhibited melanin synthesis in melanocytes and pigmentation in a human skin model. On the contrary, an inhibitor of primary cilium formation, ciliobrevin A1, activated melanogenesis in melanocytes. These results suggest that skin pigmentation may be regulated partly by the induction of ciliogenesis through Smo-GLI2 signaling.

  11. Body Site Is a More Determinant Factor than Human Population Diversity in the Healthy Skin Microbiome.

    Directory of Open Access Journals (Sweden)

    Guillermo I Perez Perez

    Full Text Available We studied skin microbiota present in three skin sites (forearm, axilla, scalp in men from six ethnic groups living in New York City.Samples were obtained at baseline and after four days following use of neutral soap and stopping regular hygiene products, including shampoos and deodorants. DNA was extracted using the MoBio Power Lyzer kit and 16S rRNA gene sequences determined on the IIlumina MiSeq platform, using QIIME for analysis.Our analysis confirmed skin swabbing as a useful method for sampling different areas of the skin because DNA concentrations and number of sequences obtained across subject libraries were similar. We confirmed that skin location was the main factor determining the composition of bacterial communities. Alpha diversity, expressed as number of species observed, was greater in arm than on scalp or axilla in all studied groups. We observed an unexpected increase in α-diversity on arm, with similar tendency on scalp, in the South Asian group after subjects stopped using their regular shampoos and deodorants. Significant differences at phylum and genus levels were observed between subjects of the different ethnic origins at all skin sites.We conclude that ethnicity and particular soap and shampoo practices are secondary factors compared to the ecological zone of the human body in determining cutaneous microbiota composition.

  12. Refractive indices of human skin tissues at eight wavelengths and estimated dispersion relations between 300 and 1600 nm

    Energy Technology Data Exchange (ETDEWEB)

    Ding Huafeng [Department of Physics, East Carolina University, Greenville, NC 27858 (United States); Lu, Jun Q [Department of Physics, East Carolina University, Greenville, NC 27858 (United States); Wooden, William A [Department of Surgery, Brody School of Medicine, East Carolina University, Greenville, NC 27858 (United States); Kragel, Peter J [Department of Pathology, Brody School of Medicine, East Carolina University, Greenville, NC 27858 (United States); Hu Xinhua [Department of Physics, East Carolina University, Greenville, NC 27858 (United States)

    2006-03-21

    The refractive index of human skin tissues is an important parameter in characterizing the optical response of the skin. We extended a previously developed method of coherent reflectance curve measurement to determine the in vitro values of the complex refractive indices of epidermal and dermal tissues from fresh human skin samples at eight wavelengths between 325 and 1557 nm. Based on these results, dispersion relations of the real refractive index have been obtained and compared in the same spectral region.

  13. Sulfur Mustard (SM) Lesions in Organ-Cultured Human Skin: Markers of Injury and Inflammatory Mediators

    Science.gov (United States)

    1990-04-16

    limited to 3 or 4 days (15) and that the circulatory and lymphatic systems are non-functional. Also, human skin is not always available from surgical... sarcoidosis . J Clin Invest 1985, Ui: 911-914. 70. Katz J, Sellers AL, Bonorris %, Golden S: Studies on extravascular albumin of r~ats. In: Plasma Protetin

  14. Differential effects of chemical irritants in rabbit and human skin organ cultures

    NARCIS (Netherlands)

    Sandt, J.J.M. van de; Rutten, A.A.J.J.L.

    1995-01-01

    The toxicity of well known irritants was investigated in rabbit and human skin organ cultures. Test chemicals were selected from various categories of irritants and included both water-soluble and water-insoluble compounds. Using a highly standardized protocol, test chemicals were applied topically

  15. Superresolution and Fluorescence Dynamics Evidence Reveal That Intact Liposomes Do Not Cross the Human Skin Barrier

    DEFF Research Database (Denmark)

    Dreier, Jes; Sørensen, Jens A; Brewer, Jonathan R

    2016-01-01

    In this study we use the combination of super resolution optical microscopy and raster image correlation spectroscopy (RICS) to study the mechanism of action of liposomes as transdermal drug delivery systems in human skin. Two different compositions of liposomes were applied to newly excised huma...

  16. The "Human Colour" Crayon: Investigating the Attitudes and Perceptions of Learners Regarding Race and Skin Colour

    Science.gov (United States)

    Alexander, Neeske; Costandius, Elmarie

    2017-01-01

    Some coloured and black learners in South Africa use a light orange or pink crayon to represent themselves in art. Many learners name this colour "human colour" or "skin colour". This is troublesome, because it could reflect exclusionary ways of representing race in images and language. This case study, conducted with two…

  17. Influence of caffeine and hyaluronic acid on collagen biosynthesis in human skin fibroblasts.

    Science.gov (United States)

    Donejko, Magdalena; Przylipiak, Andrzej; Rysiak, Edyta; Głuszuk, Katarzyna; Surażyński, Arkadiusz

    2014-01-01

    The aim of this study was to evaluate the effect of caffeine on collagen biosynthesis in human skin fibroblasts and the influence of hyaluronic acid (HA) on this process. Collagen, [(3)H]-thymidine incorporation, and prolidase activity were measured in confluent human skin fibroblast cultures that had been treated with 1, 2, and 5 mM caffeine and with caffeine and 500 μg/mL HA. Western immunoblot analysis was performed to evaluate expression of β1-integrin receptor, insulin-like growth factor receptor phospho-Akt protein and mitogen-activated protein kinase (phospho-extracellular signal-regulated kinase). Caffeine inhibited collagen biosynthesis in a dose-dependent manner. The mechanism of this process was found at the level of prolidase activity. Caffeine significantly inhibited the enzyme activity. The addition of HA had no effect on collagen biosynthesis or prolidase activity in fibroblasts incubated with caffeine. Caffeine also had an inhibitory effect on DNA biosynthesis. HA, however, did not have any significant effect on this process. The inhibition of the expression of β1-integrin and insulin-like growth factor receptor in fibroblasts incubated with the caffeine indicates a possible mechanism of inhibition of collagen biosynthesis. Caffeine reduces collagen synthesis in human cultured skin fibroblasts. HA did not have any significant protective effect on this process. This is the first study to our knowledge that reports caffeine-induced inhibition of collagen synthesis in human skin fibroblasts.

  18. Immunochemical detection of sulfur mustard adducts with keratins in the stratum corneum of human skin

    NARCIS (Netherlands)

    Schans, G.P. van der; Noort, D.; Mars-Groenendijk, R.H.; Fidder, A.; Chau, L.F.; Jong, L.P.A. de; Benschop, H.P.

    2002-01-01

    As part of a program to develop methods for diagnosis of exposure to chemical warfare agents, we developed immunochemical methods for detection of adducts of sulfur mustard to keratin in human skin. Three partial sequences of keratins containing glutamine or asparagine adducted with a

  19. Effect of elevating the skin temperature during topical ALA application on in vitro ALA penetration through mouse skin and in vivo PpIX production in human skin

    NARCIS (Netherlands)

    van den Akker, Johanna T. H. M.; Boot, Kristian; Vernon, David I.; Brown, Stanley B.; Groenendijk, Laurens; van Rhoon, Gerard C.; Sterenborg, Henricus J. C. M.

    2004-01-01

    An approach to induce increased protoporphyrin IX (PpIX) production in aminolevulinic acid (ALA)-based photodynamic therapy (PDT) of skin lesions is to elevate the skin temperature during topical ALA application. Increased skin temperature may increase the ( depth of) penetration of ALA into the

  20. Using a portable terahertz spectrometer to measure the optical properties of in vivo human skin

    Science.gov (United States)

    Echchgadda, Ibtissam; Grundt, Jessica A.; Tarango, Melissa; Ibey, Bennett L.; Tongue, Thomas; Liang, Min; Xin, Hao; Wilmink, Gerald J.

    2013-12-01

    Terahertz (THz) time-domain spectroscopy systems permit the measurement of a tissue's hydration level. This feature makes THz spectrometers excellent tools for the noninvasive assessment of skin; however, current systems are large, heavy and not ideal for clinical settings. We previously demonstrated that a portable, compact THz spectrometer permitted measurement of porcine skin optical properties that were comparable to those collected with conventional systems. In order to move toward human use of this system, the goal for this study was to measure the absorption coefficient (μa) and index of refraction (n) of human subjects in vivo. Spectra were collected from 0.1 to 2 THz, and measurements were made from skin at three sites: the palm, ventral and dorsal forearm. Additionally, we used a multiprobe adapter system to measure each subject's skin hydration levels, transepidermal water loss, and melanin concentration. Our results suggest that the measured optical properties varied considerably for skin tissues that exhibited dissimilar hydration levels. These data provide a framework for using compact THz spectrometers for clinical applications.

  1. Ex vivo permeation of carprofen from nanoparticles: A comprehensive study through human, porcine and bovine skin as anti-inflammatory agent.

    Science.gov (United States)

    Parra, Alexander; Clares, Beatriz; Rosselló, Ana; Garduño-Ramírez, María L; Abrego, Guadalupe; García, María L; Calpena, Ana C

    2016-03-30

    The purpose of this study was the development of poly(d,l-lactide-co-glycolide) acid (PLGA) nanoparticles (NPs) for the dermal delivery of carprofen (CP). The developed nanovehicle was then lyophilized using hydroxypropyl-β-cyclodextrin (HPβCD) as cryoprotectant. The ex vivo permeation profiles were evaluated using Franz diffusion cells using three different types of skin membranes: human, porcine and bovine. Furthermore, biomechanical properties of skin (trans-epidermal water loss and skin hydration) were tested. Finally, the in vivo skin irritation and the anti-inflammatory efficacy were also assayed. Results demonstrated the achievement of NPs 187.32 nm sized with homogeneous distribution, negatively charged surface (-23.39 mV) and high CP entrapment efficiency (75.38%). Permeation studies showed similar diffusion values between human and porcine skins and higher for bovine. No signs of skin irritation were observed in rabbits. Topically applied NPs significantly decreased in vivo inflammation compared to the reference drug in a TPA-induced mouse ear edema model. Thus, it was concluded that NPs containing CP may be a useful tool for the dermal treatment of local inflammation. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Vestibular Modulation of Sympathetic Nerve Activity to Muscle and Skin in Humans

    OpenAIRE

    Hammam, Elie; Vaughan G Macefield

    2017-01-01

    We review the existence of vestibulosympathetic reflexes in humans. While several methods to activate the human vestibular apparatus have been used, galvanic vestibular stimulation (GVS) is a means of selectively modulating vestibular afferent activity via electrodes over the mastoid processes, causing robust vestibular illusions of side-to-side movement. Sinusoidal GVS (sGVS) causes partial entrainment of sympathetic outflow to muscle and skin. Modulation of muscle sympathetic nerve activity...

  3. In vivo characterization of structural and optical properties of human skin by combined photothermal radiometry and diffuse reflectance spectroscopy

    Science.gov (United States)

    Verdel, Nina; Marin, Ana; Vidovič, Luka; Milanič, Matija; Majaron, Boris

    2017-02-01

    We have combined two optical techniques to enable simultaneous assessment of structure and composition of human skin in vivo: Pulsed photothermal radiometry (PPTR), which involves measurements of transient dynamics in midinfrared emission from sample surface after exposure to a light pulse, and diffuse reflectance spectroscopy (DRS) in visible part of the spectrum. Namely, while PPTR is highly sensitive to depth distribution of selected absorbers, DRS provides spectral information and thus enables differentiation between various chromophores. The accuracy and robustness of the inverse analysis is thus considerably improved compared to use of either technique on its own. Our analysis approach is simultaneous multi-dimensional fitting of the measured PPTR signals and DRS with predictions from a numerical model of light-tissue interaction (a.k.a. inverse Monte Carlo). By using a three-layer skin model (epidermis, dermis, and subcutis), we obtain a good match between the experimental and modeling data. However, dividing the dermis into two separate layers (i.e., papillary and reticular dermis) helps to bring all assessed parameter values within anatomically and physiologically plausible intervals. Both the quality of the fit and the assessed parameter values depend somewhat on the assumed scattering properties for skin, which vary in literature and likely depend on subject's age and gender, anatomical site, etc. In our preliminary experience, simultaneous fitting of the scattering properties is possible and leads to considerable improvement of the fit. The described approach may thus have a potential for simultaneous determination of absorption and scattering properties of human skin in vivo.

  4. The effect of local heat and cold therapy on the intra-articular and skin surface temperature of the knee

    OpenAIRE

    Oosterveld, F. G. J.; Rasker, Hans J.; Jacobs, J.W.G.; Overmars, H.J.A.

    1992-01-01

    Objective. To evaluate the effects of local application of ice chips, ligno-paraffin, short-wave diathermy, and nitrogen-cold air on skin and intraarticular temperature. Methods. Forty-two healthy subjects were divided into 4 treatment groups. A temperature probe was inserted into the knee joint cavity and another placed on the overlying skin, and changes in temperature over 3 hours, by treatment group, were recorded. Results. The mean skin surface temperature dropped from 27.9°C to 11.5°C af...

  5. Skin Surface pH in Acne Vulgaris: Insights from an Observational Study and Review of the Literature.

    Science.gov (United States)

    Prakash, Chaitra; Bhargava, Puneet; Tiwari, Siddhi; Majumdar, Banashree; Bhargava, Rishi Kumar

    2017-07-01

    OBJECTIVE: Recurrent and chronic course of acne vulgaris, despite effect-proven therapies, point to an underfocused aspect in its pathogenesis and management. This study aims to assess in subjects with and without acne, the skin surface pH, a parameter that cumulatively represents functioning of various units of skin, including the barrier. METHODS: A total of 200 patients with acne and 200 age- and sex-matched controls were included. Under basal conditions, facial skin pH was derived from five sites using a skin pH-meter. The relation between skin pH and acne was evaluated according to sex. RESULTS: There were more subjects with normal skin pH in the control group compared to the case group, and the majority of acne occurrences in the case group were related to high skin pH (p=0.000). Mean pH among cases was higher than normal reference value (pH 4.5-5.5 for women, 4-5.5 for men) and that of controls p (0.05). CONCLUSION: Increased facial skin pH in patients with acne at basal conditions mirrors a chronic state of stratum corneum instability, which could be predisposing individuals to acne occurrence and/or recurrences. It could possibly be a common domain via which the classical pathomechanisms might be acting in acne. Integrating measures that maintain stratum corneum pH during therapy might prove worthwhile.

  6. Human amniotic fluid derived cells can competently substitute dermal fibroblasts in a tissue-engineered dermo-epidermal skin analog

    NARCIS (Netherlands)

    Hartmann-Fritsch, Fabienne; Hosper, Nynke; Luginbuehl, Joachim; Biedermann, Thomas; Reichmann, Ernst; Meuli, Martin

    Human amniotic fluid comprises cells with high differentiation capacity, thus representing a potential cell source for skin tissue engineering. In this experimental study, we investigated the ability of human amniotic fluid derived cells to substitute dermal fibroblasts and support epidermis

  7. Noninvasive laser Raman detection of carotenoid antioxidants in living human skin

    Science.gov (United States)

    Gellermann, Werner; Ermakov, Igor V.; Ermakova, Maia R.; McClane, Robert W.

    2001-05-01

    We have used resonance Raman scattering as a novel non- invasive optical technology to measure carotenoid antioxidants in human skin of healthy volunteers. Using blue-green laser excitation, clearly distinguishable carotenoid Raman spectra are obtained which are superimposed on a large skin autofluorescence background. The Raman spectra are obtained rapidly, i.e. within about 30 seconds, and the required laser light exposure levels are well within safety standards. Our technique can be used for rapid screening of carotenoid antioxidant levels in large populations and may have applications for assessing the risk for cutaneous diseases.

  8. Comparison of rat epidermal keratinocyte organotypic culture (ROC) with intact human skin

    DEFF Research Database (Denmark)

    Pappinen, Sari; Hermansson, Martin; Kuntsche, Judith

    2008-01-01

    The present report is a part of our continuing efforts to explore the utility of the rat epidermal keratinocyte organotypic culture (ROC) as an alternative model to human skin in transdermal drug delivery and skin irritation studies of new chemical entities and formulations. The aim of the present......-hydroxyacid-phytosphingosine ceramides (NP) were absent. Also some alterations in fatty acid profiles of ROC ceramides were noted, e.g., esterified omega-hydroxyacid-sphingosine contained increased levels of oleic acid instead of linoleic acid. The fraction of lipids covalently bound to corneocyte proteins was distinctly lower in ROC...

  9. Bioactive reagents used in mesotherapy for skin rejuvenation in vivo induce diverse physiological processes in human skin fibroblasts in vitro- a pilot study.

    Science.gov (United States)

    Jäger, Claudia; Brenner, Christiane; Habicht, Jüri; Wallich, Reinhard

    2012-01-01

    The promise of mesotherapy is maintenance and/or recovery of a youthful skin with a firm, bright and moisturized texture. Currently applied medications employ microinjections of hyaluronic acid, vitamins, minerals and amino acids into the superficial layer of the skin. However, the molecular and cellular processes underlying mesotherapy are still elusive. Here we analysed the effect of five distinct medication formulas on pivotal parameters involved in skin ageing, that is collagen expression, cell proliferation and morphological changes using normal human skin fibroblast cultures in vitro. Whereas in the presence of hyaluronic acid, NCTF135(®) and NCTF135HA(®) , cell proliferation was comparable to control cultures; however, with higher expression of collagen type-1, matrix metalloproteinase-1 and tissue inhibitor of matrix metalloproteinase-1, addition of Soluvit(®) N and Meso-BK led to apoptosis and/or necrosis of human fibroblasts. The data indicate that bioactive reagents currently applied for skin rejuvenation elicit strikingly divergent physiological processes in human skin fibroblast in vitro. © 2011 John Wiley & Sons A/S.

  10. Human atopic dermatitis skin-derived T cells can induce a reaction in mouse keratinocytes in vivo

    DEFF Research Database (Denmark)

    Martel, Britta C; Blom, Lars; Dyring-Andersen, Beatrice

    2015-01-01

    injection of the human AD skin-derived T cells resulted in migration of the human T cells from subcutis to the papillary dermis followed by development of erythema and edema in the mouse skin. Furthermore, the human T cells induced a transient proliferative response in the mouse keratinocytes shown......In atopic dermatitis (AD), the inflammatory response between skin infiltrating T cells and keratinocytes is fundamental to the development of chronic lesional eczema. The aim of this study was to investigate whether skin-derived T cells from AD patients could induce an inflammatory response in mice...... through keratinocyte activation and consequently cause development of eczematous lesions. Punch biopsies of lesional skin from AD patients were used to establish skin-derived T cell cultures and which were transferred into NOD.Cg-Prkd(scid) Il2rg(tm1Sug) /JicTac (NOG) mice. We found that subcutaneous...

  11. Toward Improved Validation of Satellite Sea Surface Skin Temperature Measurements for Climate Research.

    Science.gov (United States)

    Donlon, C. J.; Minnett, P. J.; Gentemann, C.; Nightingale, T. J.; Barton, I. J.; Ward, B.; Murray, M. J.

    2002-02-01

    A poor validation strategy will compromise the quality of satellite-derived sea surface temperature (SST) products because confidence limits cannot be quantified. This paper addresses the question of how to provide the best operational strategy to validate satellite-derived skin sea surface temperature (SSTskin) measurements. High quality in situ observations obtained using different state-of-the-art infrared radiometer systems are used to characterize the relationship between the SSTskin, the subsurface SST at depth (SSTdepth), and the surface wind speed. Data are presented for different oceans and seasons. These data indicate that above a wind speed of approximately 6 m s1 the relationship between the SSTskin and SSTdepth, is well characterized for both day- and nighttime conditions by a cool bias of 0.17 ± 0.07 K rms. At lower wind speeds, stratification of the upper-ocean layers during the day may complicate the relationship, while at night a cooler skin is normally observed. Based on these observations, a long-term global satellite SSTskin validation strategy is proposed. Emphasis is placed on the use of autonomous, ship-of-opportunity radiometer systems for areas characterized by prevailing low-wind speed conditions. For areas characterized by higher wind speed regimes, well-calibrated, quality-controlled, ship and buoy SSTdepth observations, corrected for a cool skin bias, should also be used. It is foreseen that SSTdepth data will provide the majority of in situ validation data required for operational satellite SST validation. We test the strategy using SSTskin observations from the Along Track Scanning Radiometer, which are shown to be accurate to approximately 0.2 K in the tropical Pacific Ocean, and using measurements from the Advanced Very High Resolution Radiometer. We note that this strategy provides for robust retrospective calibration and validation of satellite SST data and a means to compare and compile in a meaningful and consistent fashion

  12. Biological stimulation of the Human skin applying health promoting light and plasma sources

    Energy Technology Data Exchange (ETDEWEB)

    Awakowicz, P.; Bibinov, N. [Center for Plasma Science and Technology, Ruhr-University, Bochum (Germany); Born, M.; Niemann, U. [Philips Research, Aachen (Germany); Busse, B. [Zell-Kontakt GmbH, Noerten-Hardenberg (Germany); Gesche, R.; Kuehn, S.; Porteanu, H.E. [Ferdinand-Braun-Institut fuer Hoechstfrequenztechnik, Berlin (Germany); Helmke, A. [University of Applied Sciences and Arts, Goettingen (Germany); Kaemling, A.; Wandke, D. [CINOGY GmbH, Duderstadt (Germany); Kolb-Bachofen, V.; Liebmann, J. [Institute for Immunobiology, Heinrich-Heine University, Duesseldorf (Germany); Kovacs, R.; Mertens, N.; Scherer, J. [Aurion Anlagentechnik GmbH, Seligenstadt (Germany); Oplaender, C.; Suschek, C. [Clinic for Plastic Surgery, University Clinic, Aachen (Germany); Vioel, W. [Laser-Laboratorium, Goettingen (Germany); University of Applied Sciences and Arts, Goettingen (Germany)

    2009-10-15

    In the frame of BMBF project ''BioLiP'', new physical treatment techniques aiming at medical treatment of the human skin have been developed. The acronym BioLiP stands for ''Desinfektion, Entkeimung und biologische Stimulation der Haut durch gesundheitsfoerdernde Licht- und Plasmaquellen'' (Disinfection, germ reduction and biological stimulation of the human skin by health promoting light and plasma sources). A source applying a low-temperature dielectric barrier discharge plasma (DBD) has been investigated on its effectiveness for skin disinfection and stimulation of biological material. Alternatively an atmospheric plasma source consisting of a microwave resonator combined with a solid state power oscillator has been examined. This concept which allows for a compact and efficient design avoiding external microwave power supply and matching units has been optimized with respect to nitrogen monoxide (NO) production in high yields. In both cases various application possibilities in the medical and biological domain are opened up. Light sources in the visible spectral range have been investigated with respect to the proliferation of human cell types. Intensive highly selective blue light sources based on LED technology can slow down proliferation rates without inducing toxic effects which offers new opportunities for treatments of so-called hyperproliferative skin conditions (e.g. with psoriasis or in wound healing) using UV-free light. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  13. CCL18 is expressed in atopic dermatitis and mediates skin homing of human memory T cells.

    Science.gov (United States)

    Günther, Claudia; Bello-Fernandez, Concha; Kopp, Tamara; Kund, Julia; Carballido-Perrig, Nicole; Hinteregger, Sonja; Fassl, Sandra; Schwärzler, Christoph; Lametschwandtner, Günther; Stingl, Georg; Biedermann, Tilo; Carballido, José M

    2005-02-01

    CCL18 is a human chemokine secreted by monocytes and dendritic cells. The receptor for CCL18 is not yet known and the functions of this chemokine on immune cells are not fully elucidated. In this study, we describe that CCL18 is present in skin biopsies of atopic dermatitis (AD) patients but not in normal or psoriatic skin. CCL18 was specifically expressed by APCs in the dermis and by Langerhans and inflammatory dendritic epidermal cells in the epidermis. In addition, the serum levels of CCL18 and the percentages of CCL18-producing monocyte/macrophages and dendritic cells were significantly increased in AD patients compared with healthy controls. Furthermore, we demonstrate that CCL18 binds to CLA(+) T cells in peripheral blood of AD patients and healthy individuals and induces migration of AD-derived memory T cells in vitro and in human skin-transplanted SCID mice. These findings highlight a unique role of CCL18 in AD and reveal a novel function of this chemokine mediating skin homing of a subpopulation of human memory T cells.

  14. Collagen cross-linking in sun-exposed and unexposed sites of aged human skin

    Science.gov (United States)

    Yamauchi, M.; Prisayanh, P.; Haque, Z.; Woodley, D. T.

    1991-01-01

    A recently described nonreducible, acid-heat stable compound, histidinohydroxylysinonorleucine (HHL), is a collagen cross-link isolated from mature skin tissue. Its abundance is related to chronologic aging of skin. The present communication describes the quantity of HHL from aged human skin of the same individuals in sun-exposed (wrist) and unexposed (buttock) sites. Punch biopsies were obtained from these sites from nine people of age 60 or older. HHL contents (moles/mole of collagen) at these sites were for wrist 0.13 +/- 0.07 and for buttock 0.69 +/- 0.17 (mean +/- SD, p less than 0.001). In addition, it was found that acute irradiation of the cross-linked peptides with UVA (up to 250 J/cm2) and UVB (up to 1 J/cm2) had no effect on HHL structure. The same treatment significantly degraded another nonreducible, stable collagen cross-link, pyridinoline. The results suggest that chronic sunlight exposure may be associated with an impediment to normal maturation of human dermal collagen resulting in tenuous amount of HHL. Thus, the process of photoaging in dermal collagen is different from that of chronologic aging in human skin.

  15. A rising cancer prevention target of RSK2 in human skin cancer

    Directory of Open Access Journals (Sweden)

    Arul eNarayanasamy

    2013-08-01

    Full Text Available RSK2 is a p90 ribosomal S6 kinase family (p90RSK member regulating cell proliferation and transformation induced by tumor promoters such as epithelial growth factor (EGF and 12-O-tetradecanoylphorbol 13-acetate (TPA. This family of p90RSK has classified as a serine/threonine kinase that respond to many growth factors, peptide hormones, neurotransmitters, and environmental stresses such as ultraviolet light (UV. Our recent study demonstrates that RSK2 plays a key role in human skin cancer development. Activation of RSK2 by EGF and UV through ERKs signaling pathway induces cell cycle progression, cell proliferation and anchorage-independent cell transformation. Moreover, knockdown of RSK2 by si-RNA or sh-RNA abrogates cell proliferation and cell transformation of non-malignant human skin keratinocyte, and colony growth of malignant melanoma cells in soft agar. Importantly, activated and total RSK2 protein levels are highly detected in human skin cancer tissues including squamous cell carcinoma, basal cell carcinoma and malignant melanoma. Kaempferol and eriodictyol are natural substances to inhibit kinase activity of the RSK2 N-terminal kinase domain, which is a critical kinase domain to transducer their activation signals to the substrates by phosphorylation. In this review, we discuss the role of RSK2 in skin cancer particularly, in activation of signaling pathways and potent natural substances to target RSK2 as chemopreventive and therapeutic agents.

  16. Human Mars Surface Mission Nuclear Power Considerations

    Science.gov (United States)

    Rucker, Michelle A.

    2018-01-01

    A key decision facing Mars mission designers is how to power a crewed surface field station. Unlike the solar-powered Mars Exploration Rovers (MER) that could retreat to a very low power state during a Martian dust storm, human Mars surface missions are estimated to need at least 15 kilowatts of electrical (kWe) power simply to maintain critical life support and spacecraft functions. 'Hotel' loads alone for a pressurized crew rover approach two kWe; driving requires another five kWe-well beyond what the Curiosity rover’s Radioisotope Power System (RPS) was designed to deliver. Full operation of a four-crew Mars field station is estimated at about 40 kWe. Clearly, a crewed Mars field station will require a substantial and reliable power source, beyond the scale of robotic mission experience. This paper explores the applications for both fission and RPS nuclear options for Mars.

  17. Detection of capecitabine (Xeloda®) on the skin surface after oral administration.

    Science.gov (United States)

    Huang, Mao-Dong; Fuss, Harald; Lademann, Jürgen; Florek, Stefan; Patzelt, Alexa; Meinke, Martina C; Jung, Sora

    2016-04-30

    Palmoplantar erythrodysesthesia (PPE), or hand-foot syndrome, is a cutaneous toxicity under various chemotherapeutics contributing to the most frequent side effects in patients treated with capecitabine (Xeloda®). The pathomechanism of PPE has been unclear. Here, the topical detection of capecitabine in the skin after oral application was shown in 10 patients receiving 2500  mg/m 2 /day 2500  mg/m2/day capecitabine. Sweat samples were taken prior to and one week after oral administration of capecitabine. Using high-resolution continuum source absorption spectrometry, the changes in concentrations of fluorine, which is an ingredient of capecitabine, were quantified and statistically analyzed. Here, we show an increase in fluorine concentrations from 40±10  ppb 40±10  ppb (2±0.5  pM 2±0.5  pM ) before capecitabine administration to 27.7±11.8  ppm 27.7±11.8  ppm (14.6±6.5  nM 14.6±6.5  nM ) after application, p<0.001 p<0.001 . The results show the secretion of capecitabine on the skin surface after oral administration, indicating a local toxic effect as a possible pathomechanism of PPE.

  18. Detection of capecitabine (Xeloda®) on the skin surface after oral administration

    Science.gov (United States)

    Huang, Mao-Dong; Fuss, Harald; Lademann, Jürgen; Florek, Stefan; Patzelt, Alexa; Meinke, Martina C.; Jung, Sora

    2016-04-01

    Palmoplantar erythrodysesthesia (PPE), or hand-foot syndrome, is a cutaneous toxicity under various chemotherapeutics contributing to the most frequent side effects in patients treated with capecitabine (Xeloda®). The pathomechanism of PPE has been unclear. Here, the topical detection of capecitabine in the skin after oral application was shown in 10 patients receiving 2500 mg/m2/day capecitabine. Sweat samples were taken prior to and one week after oral administration of capecitabine. Using high-resolution continuum source absorption spectrometry, the changes in concentrations of fluorine, which is an ingredient of capecitabine, were quantified and statistically analyzed. Here, we show an increase in fluorine concentrations from 40±10 ppb (2±0.5 pM) before capecitabine administration to 27.7±11.8 ppm (14.6±6.5 nM) after application, p<0.001. The results show the secretion of capecitabine on the skin surface after oral administration, indicating a local toxic effect as a possible pathomechanism of PPE.

  19. Thermographic mapping of the skin surface in biometric evaluation of cellulite treatment effectiveness.

    Science.gov (United States)

    Wilczyński, S; Koprowski, R; Deda, A; Janiczek, M; Kuleczka, N; Błońska-Fajfrowska, B

    2017-02-01

    Cellulite is one of the worst tolerated aesthetic imperfections. Edema that accompanies cellulite causes disorders of blood flow what may be observed as changes in the skin surface temperature. The aim of this paper was to develop a new method based on the analysis and processing of thermal images of the skin for biometric evaluation of severity of cellulite and monitoring its treatment. The observations of the treatment effects were conducted on 10 females (33.4 ± 6.4 years). Thermal images of the volunteers' thighs were captured before starting the therapy (T 0 ). In the following stages: T 1 , T 2 , and T 3 , thermal images were captured 2 weeks after the first, second and third Alidya treatment administration, respectively. Profiled algorithms were developed to determine the mean Grey Level Co-occurrence Matrix (GLCM) contrast in the acquired thermograms. The mean GLCM contrast for the phase T 0 was 70.91, and for the stages T 1 , T 2 , and T 3 : 57.78, 41.80, and 38.53, respectively. The use of proposed method (GLCM contrast) enables biometric evaluation of the effectiveness of cellulite treatment. Traditionally used parameters of infrared analysis such as local points of the maximum and minimum temperature or the median temperatures are not useful in thermal, biometric evaluation of anti-cellulite preparations. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Your Skin

    Science.gov (United States)

    ... and a little waterproofing. previous continue Skin Can Warm and Cool You Your skin can help if you're feeling too hot or too cold. Your blood ... you're ice-skating or sledding? When you're cold, your blood vessels keep your ... and keeping the warm blood away from the skin's surface. You might ...

  1. Metal nanoparticles in dermatology and cosmetology: Interactions with human skin cells.

    Science.gov (United States)

    Niska, Karolina; Zielinska, Ewelina; Radomski, Marek Witold; Inkielewicz-Stepniak, Iwona

    2017-06-19

    Nanotechnology is a rapidly developing branch of science, which studies control of phenomena and materials sized below 100 nm. Nanotechnology is applicable in many areas of life and medicine including skin care and personal hygiene. The nanoparticles (NPs) of metals and metal oxides are increasingly used in dermatology and cosmetology, especially in prevention and treatment of bacterial and fungal infections, in protection against the harmful effects of the sun and in preparations reducing the visibility of scars by accelerating the repair processes of skin cells. NPs may also be used for skin care and dermatological treatments to improve the quality of life of patients. Nanodermatology and nanocosmetology offer effective, safe, fast-acting product formulations, thus minimizing the side effects of the products used so far. The unique properties of NPs: high surface area relative to the size as well as the ability to penetrate biological membranes and barriers greatly reduces systemic dose thus potential side effects and toxicity. Recent studies show very promising clinical potential of NPs to serve as controlled release and delivery systems for drugs/active substances. In addition, NPs can be used in diagnostic imaging of skin diseases. However, NPs may also carry a risk of cytotoxicity and side effects. The present review focuses on the use of metal and metal oxide NPs in dermatology and cosmetology and their interactions with skin cells. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Effects of Lip Color on Perceived Lightness of Human Facial Skin.

    Science.gov (United States)

    Kobayashi, Yuki; Matsushita, Soyogu; Morikawa, Kazunori

    2017-01-01

    Whereas geometric illusions in human faces have been reported by several studies, illusions of color or lightness in faces have seldom been explored. Here, we psychophysically investigated whether lip color influences facial skin's perceived lightness. Results of Experiment 1 demonstrated that redder lips lightened and darker lips darkened the perceived complexion. These lightness or darkness inducing effects differ from the classical illusion of lightness contrast in nonface objects for two reasons. First, illusory effects are more assimilative than contrastive. Second, the inducing area (i.e., lips) is much smaller than the influenced area (facial skin). Experiment 2 showed that the assimilative lightness induction was caused by holistic processing of faces. This is the first study to scientifically substantiate the claim of cosmetics manufacturers and makeup artists that lip colors can alter perceived facial skin color. Implications for face perception, lightness illusion, and perceptual effects of cosmetics are discussed.

  3. Gene expression time course in the human skin during elicitation of allergic contact dermatitis

    DEFF Research Database (Denmark)

    Pedersen, Malene; Skov, Lone; Menné, Torkil

    2007-01-01

    Genes involved in the inflammatory response resulting in allergic contact dermatitis (ACD) are only partly known. In this study, we introduce the use of high-density oligonucleotide arrays for gene expression profiling in human skin during the elicitation of ACD. Skin biopsies from normal...... and nickel-exposed skin were obtained from seven nickel-allergic patients and five nonallergic controls at four different time points during elicitation of eczema. Each gene expression profile was analyzed by hybridization to high-density oligonucleotide arrays. Cluster analysis of 74 genes found...... to be differentially expressed in the patients over time revealed that the patient samples may be categorized into two groups: an early time-point group (no clinical reaction) and a late time-point group (clinical reaction). Bioinformatics analyses unraveled the potential involvement of signal transducers...

  4. The "Human Colour" Crayon: Investigating the Attitudes and Perceptions of Learners regarding Race and Skin Colour

    Directory of Open Access Journals (Sweden)

    Neeske Alexander

    2017-07-01

    Full Text Available Some coloured and black learners in South Africa use a light orange or pink crayon to represent themselves in art. Many learners name this colour “human colour” or “skin colour”. This is troublesome, because it could reflect exclusionary ways of representing race in images and language. This case study, conducted with two schools in the Western Cape, investigated Grade 3 learners’ attitudes and perceptions regarding race and skin colour through art processes and discussion. The aim was to promote critical engagement with race in Foundation Phase educational contexts. Suggestions include changing the language used to describe skin colour, just recognition and representation of races in educational resources and the promotion of critical citizenship education. This research indicates the need to create practical curriculum guidelines to discuss race issues in the South African classroom.

  5. Global Skin-Friction Measurements Using Particle Image Surface FLow Visualization and a Luminescent Oil-Film

    Science.gov (United States)

    Husen, Nicholas; Roozeboom, Nettie; Liu, Tianshu; Sullivan, John P.

    2015-01-01

    A quantitative global skin-friction measurement technique is proposed. An oil-film is doped with a luminescent molecule and thereby made to fluoresce in order to resolve oil-film thickness, and Particle Image Surface Flow Visualization is used to resolve the velocity field of the surface of the oil-film. Skin-friction is then calculated at location x as (x )xh, where x is the displacement of the surface of the oil-film and is the dynamic viscosity of the oil. The data collection procedure and data analysis procedures are explained, and preliminary experimental skin-friction results for flow over the wing of the CRM are presented.

  6. Skin Protective Effects of Nannochloropsis gaditana Extract on H2O2-Stressed Human Dermal Fibroblasts

    Directory of Open Access Journals (Sweden)

    Sophia Letsiou

    2017-07-01

    Full Text Available Nowadays, there is huge interest in natural products obtained from marine organisms that can promote a state of health and well-being for humans. Microalgae represent a primary source of bioactive compounds that could be used as functional ingredients in cosmetic formulations. The aim of the present study is to evaluate, for the first time, the effects of Nannochloropsis gaditana extract against oxidative stress in human primary fibroblasts so as to investigate the potential applications of it in cosmetics. To gain an insight into the molecular mechanisms of N. gaditana bioactivity, we developed a new RT-qPCR platform for studying transcript accumulation for an array of selected genes (up to 100 involved in many skin-related processes including anti-aging, hydration, oxidative stress response, and DNA damage. For the oxidative stress evaluation, H2O2 was used as a stressor. The study of the transcript accumulation of genes revealed that N. gaditana extract exhibits skin protection properties by mediating oxidative responses and apoptosis (including SOD1, GPX1, BID, positively regulates genes involves in skin texture and hydration (including AQP3, Col6A1, FBN1 and modulates the expression of genes involved in skin irritation, DNA damage and aging (including IL1R, PCNA, FOXO3. These findings indicate that the specific N. gaditana extract possesses significant in vitro skin protection activity against induced oxidative stress, and provide new insights into the beneficial role of microalgae bioactive compounds in cosmetic formulations protecting skin from oxidative stress.

  7. Noncanonical microRNAs and endogenous siRNAs in normal and psoriatic human skin.

    Science.gov (United States)

    Xia, Jing; Joyce, Cailin E; Bowcock, Anne M; Zhang, Weixiong

    2013-02-15

    Noncanonical microRNAs (miRNAs) and endogenous small interfering RNAs (endo-siRNAs) are key gene regulators in eukaryotes. Noncanonical miRNAs, which bypass part of the canonical miRNA biogenesis pathway, can originate from a variety of genomic loci, which include small nucleolar RNAs (snoRNAs), transfer RNAs (tRNAs) and introns, whereas endo-siRNAs can arise from repetitive elements, some of which are transposable. The roles of noncanonical miRNAs and endo-siRNAs in complex diseases have yet to be characterized. To investigate their potential expression and function in psoriasis, we carried out a comprehensive, genome-wide search for noncanonical miRNAs and endo-siRNAs in small RNA deep-sequencing data sets from normal and psoriatic human skin. By analyzing more than 670 million qualified reads from 67 small RNA libraries, we identified 21 novel, noncanonical miRNAs (3 snoRNA-derived and 2 tRNA-derived miRNAs and 16 miRtrons) and 39 novel endo-siRNAs that were expressed in skin. The expression of four novel small RNAs was validated by qRT-PCR in human skin, and their Argonaute association was confirmed by co-immunoprecipitation of ectopic small RNAs in HEK293 cells. Fifteen noncanonical miRNAs or endo-siRNAs were significantly differentially expressed in psoriatic-involved versus normal skin, including an Alu-short interspersed element-derived siRNA which was 17-fold up-regulated in psoriatic-involved skin. These and other differentially expressed small noncoding RNAs may function as regulators of gene expression in skin and potentially play a role in psoriasis pathogenesis.

  8. Effects of niacin restriction on sirtuin and PARP responses to photodamage in human skin.

    Directory of Open Access Journals (Sweden)

    Claudia A Benavente

    Full Text Available Sirtuins (SIRTs and poly(ADP-ribose polymerases (PARPs, NAD(+-dependent enzymes, link cellular energy status with responses to environmental stresses. Skin is frequently exposed to the DNA damaging effects of UV irradiation, a known etiology in skin cancer. Thus, understanding the defense mechanisms in response to UV, including the role of SIRTs and PARPs, may be important in developing skin cancer prevention strategies. Here, we report expression of the seven SIRT family members in human skin. SIRTs gene expressions are progressively upregulated in A431 epidermoid carcinoma cells (SIRTs1 and 3, actinic keratoses (SIRTs 2, 3, 5, 6, and 7 and squamous cell carcinoma (SIRTs 1-7. Photodamage induces dynamic changes in SIRT expression with upregulation of both SIRT1 and SIRT4 mRNAs. Specific losses of SIRT proteins occur early after photodamage followed by accumulation later, especially for SIRT4. Niacin restriction, which decreases NAD(+, the sirtuin substrate, results in an increase in acetylated proteins, upregulation of SIRTs 2 and 4, increased inherent DNA damage, alterations in SIRT responses to photodamage, abrogation of PARP activation following photodamage, and increased sensitivity to photodamage that is completely reversed by repleting niacin. These data support the hypothesis that SIRTs and PARPs play important roles in resistance to photodamage and identify specific SIRTs that respond to photodamage and may be targets for skin cancer prevention.

  9. The electromagnetic response of human skin in the millimetre and submillimetre wave range.

    Science.gov (United States)

    Feldman, Yuri; Puzenko, Alexander; Ben Ishai, Paul; Caduff, Andreas; Davidovich, Issak; Sakran, Fadi; Agranat, Aharon J

    2009-06-07

    Recent studies of the minute morphology of the skin by optical coherence tomography revealed that the sweat ducts in human skin are helically shaped tubes, filled with a conductive aqueous solution. This, together with the fact that the dielectric permittivity of the dermis is higher than that of the epidermis, brings forward the supposition that as electromagnetic entities, the sweat ducts could be regarded as low Q helical antennas. The implications of this statement were further investigated by electromagnetic simulation and experiment of the in vivo reflectivity of the skin of subjects under varying physiological conditions (Feldman et al 2008 Phys. Rev. Lett. 100 128102). The simulation and experimental results are in a good agreement and both demonstrate that sweat ducts in the skin could indeed behave as low Q antennas. Thus, the skin spectral response in the sub-Terahertz region is governed by the level of activity of the perspiration system and shows the minimum of reflectivity at some frequencies in the frequency band of 75-110 GHz. It is also correlated to physiological stress as manifested by the pulse rate and the systolic blood pressure. As such, it has the potential to become the underlying principle for remote sensing of the physiological parameters and the mental state of the examined subject.

  10. Feasibility Study on a Microwave-Based Sensor for Measuring Hydration Level Using Human Skin Models.

    Directory of Open Access Journals (Sweden)

    Rico Brendtke

    Full Text Available Tissue dehydration results in three major types of exsiccosis--hyper-, hypo-, or isonatraemia. All three types entail alterations of salt concentrations leading to impaired biochemical processes, and can finally cause severe morbidity. The aim of our study was to demonstrate the feasibility of a microwave-based sensor technology for the non-invasive measurement of the hydration status. Electromagnetic waves at high frequencies interact with molecules, especially water. Hence, if a sample contains free water molecules, this can be detected in a reflected microwave signal. To develop the sensor system, human three-dimensional skin equivalents were instituted as a standardized test platform mimicking reproducible exsiccosis scenarios. Therefore, skin equivalents with a specific hydration and density of matrix components were generated and microwave measurements were performed. Hydration-specific spectra allowed deriving the hydration state of the skin models. A further advantage of the skin equivalents was the characterization of the impact of distinct skin components on the measured signals to investigate mechanisms of signal generation. The results demonstrate the feasibility of a non-invasive microwave-based hydration sensor technology. The sensor bears potential to be integrated in a wearable medical device for personal health monitoring.

  11. Feasibility Study on a Microwave-Based Sensor for Measuring Hydration Level Using Human Skin Models.

    Science.gov (United States)

    Brendtke, Rico; Wiehl, Michael; Groeber, Florian; Schwarz, Thomas; Walles, Heike; Hansmann, Jan

    2016-01-01

    Tissue dehydration results in three major types of exsiccosis--hyper-, hypo-, or isonatraemia. All three types entail alterations of salt concentrations leading to impaired biochemical processes, and can finally cause severe morbidity. The aim of our study was to demonstrate the feasibility of a microwave-based sensor technology for the non-invasive measurement of the hydration status. Electromagnetic waves at high frequencies interact with molecules, especially water. Hence, if a sample contains free water molecules, this can be detected in a reflected microwave signal. To develop the sensor system, human three-dimensional skin equivalents were instituted as a standardized test platform mimicking reproducible exsiccosis scenarios. Therefore, skin equivalents with a specific hydration and density of matrix components were generated and microwave measurements were performed. Hydration-specific spectra allowed deriving the hydration state of the skin models. A further advantage of the skin equivalents was the characterization of the impact of distinct skin components on the measured signals to investigate mechanisms of signal generation. The results demonstrate the feasibility of a non-invasive microwave-based hydration sensor technology. The sensor bears potential to be integrated in a wearable medical device for personal health monitoring.

  12. Effects of Niacin Restriction on Sirtuin and PARP Responses to Photodamage in Human Skin

    Science.gov (United States)

    Benavente, Claudia A.; Schnell, Stephanie A.; Jacobson, Elaine L.

    2012-01-01

    Sirtuins (SIRTs) and poly(ADP-ribose) polymerases (PARPs), NAD+-dependent enzymes, link cellular energy status with responses to environmental stresses. Skin is frequently exposed to the DNA damaging effects of UV irradiation, a known etiology in skin cancer. Thus, understanding the defense mechanisms in response to UV, including the role of SIRTs and PARPs, may be important in developing skin cancer prevention strategies. Here, we report expression of the seven SIRT family members in human skin. SIRTs gene expressions are progressively upregulated in A431 epidermoid carcinoma cells (SIRTs1 and 3), actinic keratoses (SIRTs 2, 3, 5, 6, and 7) and squamous cell carcinoma (SIRTs 1–7). Photodamage induces dynamic changes in SIRT expression with upregulation of both SIRT1 and SIRT4 mRNAs. Specific losses of SIRT proteins occur early after photodamage followed by accumulation later, especially for SIRT4. Niacin restriction, which decreases NAD+, the sirtuin substrate, results in an increase in acetylated proteins, upregulation of SIRTs 2 and 4, increased inherent DNA damage, alterations in SIRT responses to photodamage, abrogation of PARP activation following photodamage, and increased sensitivity to photodamage that is completely reversed by repleting niacin. These data support the hypothesis that SIRTs and PARPs play important roles in resistance to photodamage and identify specific SIRTs that respond to photodamage and may be targets for skin cancer prevention. PMID:22860104

  13. Penetration profile and human cadaver skin distribution of finasteride from vesicular nanocarriers.

    Science.gov (United States)

    Rao, Yuefeng; Zheng, Feiyue; Liang, Xingguang; Wang, Huiyuan; Zhang, Jin; Lu, Xiaoyang

    2015-12-01

    The skin accumulation of therapeutic agents affects the efficiency of topical drug delivery. In this study, in vitro distribution of finasteride of ethosomes and liposomes in human cadaver skin after percutaneous delivery were investigated. Experiments were performed using modified Franz diffusion cells. Finasteride ethosomes, liposomes or hydroethanolic solutions were used as donor medium. Drug distribution at different skin layers and depths were studied by hotplate separation and frozen horizontal slicing technique. The result showed that the accumulation of finasteride in skin ranged from 9.7-24.3 μg/cm(2) at 12 or 24 hours. The ethosomes demonstrated better enhancing ability to deliver finasteride into the dermis layer than liposomes did. The finasteride concentration in the dermis layer from ethosomes was more than sevenfold higher than from liposomes. The finasteride accumulation in ethosomes group showed a distinctive reversed distribution profile. This distinctive reversed distribution profile is meaningful for exerting a favorable pharmacological effect for finasteride. The drug distribution profile in skin layers showed no significant difference between 12 and 24 hours application (p > 0.05). The study demonstrated that finasteride can be accumulated at target site more effectively and maintained at higher level through the application of novel ethosomal carriers.

  14. Latitudinal Clines of the Human Vitamin D Receptor and Skin Color Genes

    Directory of Open Access Journals (Sweden)

    Dov Tiosano

    2016-05-01

    Full Text Available The well-documented latitudinal clines of genes affecting human skin color presumably arise from the need for protection from intense ultraviolet radiation (UVR vs. the need to use UVR for vitamin D synthesis. Sampling 751 subjects from a broad range of latitudes and skin colors, we investigated possible multilocus correlated adaptation of skin color genes with the vitamin D receptor gene (VDR, using a vector correlation metric and network method called BlocBuster. We discovered two multilocus networks involving VDR promoter and skin color genes that display strong latitudinal clines as multilocus networks, even though many of their single gene components do not. Considered one by one, the VDR components of these networks show diverse patterns: no cline, a weak declining latitudinal cline outside of Africa, and a strong in- vs. out-of-Africa frequency pattern. We confirmed these results with independent data from HapMap. Standard linkage disequilibrium analyses did not detect these networks. We applied BlocBuster across the entire genome, showing that our networks are significant outliers for interchromosomal disequilibrium that overlap with environmental variation relevant to the genes’ functions. These results suggest that these multilocus correlations most likely arose from a combination of parallel selective responses to a common environmental variable and coadaptation, given the known Mendelian epistasis among VDR and the skin color genes.

  15. HLA-DR alleles associated with skin warts induced by human papillomavirus infection.

    Science.gov (United States)

    García-Corona, Cristina; Vega-Memije, Elisa; Barquera, Rodrigo; Granados, Julio

    2010-12-01

    The skin wart is a benign proliferation of the skin and mucous, secondary to human papillomavirus (HPV) infection. The objective of this study is to determine gene frequencies of HLA-DR alleles in Mexican patients with skin warts and compare them with those present in ethnically matched healthy subjects. Fifty-two patients with clinically and histologically confirmed skin warts from the Dermatology Outpatient Clinic, with results of high-resolution DNA typing for HLA-DR polymorphism. HLA-DR3 and DR9 were increased (P = 0.0029, OR: 2.5, 95% CI: 1.3–4.7 and P = 0.0062, OR: 5.4, 95% CI: 1.4–19.5, respectively), and HLA-DR6 allele was found decreased (P = 0.0002). The major histocompatibility complex contribution in the infection and elimination of the virus is not clear and perhaps also contributes to a series of events not well established yet. This study follows the preponderant role of class II genes in the susceptibility or resistance to the development of skin warts caused by HPV infection.

  16. Multiple spatially resolved reflection spectroscopy for in vivo determination of carotenoids in human skin and blood

    Science.gov (United States)

    Darvin, Maxim E.; Magnussen, Björn; Lademann, Juergen; Köcher, Wolfgang

    2016-09-01

    Non-invasive measurement of carotenoid antioxidants in human skin is one of the important tasks to investigate the skin physiology in vivo. Resonance Raman spectroscopy and reflection spectroscopy are the most frequently used non-invasive techniques in dermatology and skin physiology. In the present study, an improved method based on multiple spatially resolved reflection spectroscopy (MSRRS) was introduced. The results obtained were compared with those obtained using the ‘gold standard’ resonance Raman spectroscopy method and showed strong correlations for the total carotenoid concentration (R  =  0.83) as well as for lycopene (R  =  0.80). The measurement stability was confirmed to be better than 10% within the total temperature range from 5 °C to  +  30 °C and pressure contact between the skin and the MSRRS sensor from 800 Pa to 18 000 Pa. In addition, blood samples taken from the subjects were analyzed for carotenoid concentrations. The MSRRS sensor was calibrated on the blood carotenoid concentrations resulting in being able to predict with a correlation of R  =  0.79. On the basis of blood carotenoids it could be demonstrated that the MSRRS cutaneous measurements are not influenced by Fitzpatrick skin types I-VI. The MSRRS sensor is commercially available under the brand name biozoom.

  17. The electromagnetic response of human skin in the millimetre and submillimetre wave range

    Science.gov (United States)

    Feldman, Yuri; Puzenko, Alexander; Ben Ishai, Paul; Caduff, Andreas; Davidovich, Issak; Sakran, Fadi; Agranat, Aharon J.

    2009-06-01

    Recent studies of the minute morphology of the skin by optical coherence tomography revealed that the sweat ducts in human skin are helically shaped tubes, filled with a conductive aqueous solution. This, together with the fact that the dielectric permittivity of the dermis is higher than that of the epidermis, brings forward the supposition that as electromagnetic entities, the sweat ducts could be regarded as low Q helical antennas. The implications of this statement were further investigated by electromagnetic simulation and experiment of the in vivo reflectivity of the skin of subjects under varying physiological conditions (Feldman et al 2008 Phys. Rev. Lett. 100 128102). The simulation and experimental results are in a good agreement and both demonstrate that sweat ducts in the skin could indeed behave as low Q antennas. Thus, the skin spectral response in the sub-Terahertz region is governed by the level of activity of the perspiration system and shows the minimum of reflectivity at some frequencies in the frequency band of 75-110 GHz. It is also correlated to physiological stress as manifested by the pulse rate and the systolic blood pressure. As such, it has the potential to become the underlying principle for remote sensing of the physiological parameters and the mental state of the examined subject.

  18. Impact of source position on high-dose-rate skin surface applicator dosimetry.

    Science.gov (United States)

    Jeong, Jeho; Barker, Christopher A; Zaider, Marco; Cohen, Gil'ad N

    2016-01-01

    Skin surface dosimetric discrepancies between measured and treatment planning system predicted values were traced to source position sag inside the applicator and to source transit time. We quantified their dosimetric impact and propose corrections for clinical use. We measured the dose profiles from the Varian Leipzig-style high-dose-rate (HDR) skin applicator, using EBT3 film, photon diode, and optically stimulated luminescence dosimeter for three different GammaMedplus HDR afterloaders. The measured dose profiles at several depths were compared with BrachyVision Acuros calculated profiles. To assess the impact of the source sag, two different applicator orientations were considered. The dose contribution during source transit was assessed by comparing diode measurements using an HDR timer and an electrometer timer. Depth doses measured using the three dosimeters were in good agreement, but were consistently higher than the Acuros dose calculations. Measurements with the applicator face up were significantly (exceeding 10%) lower than those in the face down position, due to source sag inside the applicator. Based on the inverse square law, the effective source sag was evaluated to be about 0.5 mm from the planned position. The additional dose during source transit was evaluated to be about 2.8% for 30 seconds of treatment with a 40700 U (10 Ci) source. With a very short source-to-surface distance, the small source sag inside the applicator has a significant dosimetric impact. This effect is unaccounted for in the vendor's treatment planning template and should be considered before the clinical use of the applicator. Further investigation of other applicators with large source lumen diameter may be warranted. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  19. Under Persistent Assault: Understanding the Factors that Deteriorate Human Skin and Clinical Efficacy of Topical Antioxidants in Treating Aging Skin

    OpenAIRE

    Patricia K. Farris; Yevgeniy Krol

    2015-01-01

    Recent studies contend that the skin is subject to far more damage than just ultraviolet (UV) light, with infrared radiation and pollution now clearly demonstrated to degrade cutaneous tissue. While consumers continue to strive for new ways to augment the aesthetic appeal and improve the health of their skin, awareness regarding environmental insults and effective ways to protect the skin remains low. New advances in dermatologic science have exponentially increased the available information ...

  20. The future of skin metagenomics.

    Science.gov (United States)

    Mathieu, Alban; Vogel, Timothy M; Simonet, Pascal

    2014-01-01

    Metagenomics, the direct exploitation of environmental microbial DNA, is complementary to traditional culture-based approaches for deciphering taxonomic and functional microbial diversity in a plethora of ecosystems, including those related to the human body such as the mouth, saliva, teeth, gut or skin. DNA extracted from human skin analyzed by sequencing the PCR-amplified rrs gene has already revealed the taxonomic diversity of microbial communities colonizing the human skin ("skin microbiome"). Each individual possesses his/her own skin microbial community structure, with marked taxonomic differences between different parts of the body and temporal evolution depending on physical and chemical conditions (sweat, washing etc.). However, technical limitations due to the low bacterial density at the surface of the human skin or contamination by human DNA still has inhibited extended use of the metagenomic approach for investigating the skin microbiome at a functional level. These difficulties have been overcome in part by the new generation of sequencing platforms that now provide sequences describing the genes and functions carried out by skin bacteria. These methodological advances should help us understand the mechanisms by which these microorganisms adapt to the specific chemical composition of each skin and thereby lead to a better understanding of bacteria/human host interdependence. This knowledge will pave the way for more systemic and individualized pharmaceutical and cosmetic applications. Copyright © 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  1. Is Agency Skin Deep? Surface Attributes Influence Infants' Sensitivity to Goal-Directed Action

    Science.gov (United States)

    Guajardo, Jose J.; Woodward, Amanda L.

    2004-01-01

    Three studies investigated the role of surface attributes in infants' identification of agents, using a habituation paradigm designed to tap infants' interpretation of grasping as goal directed (Woodward, 1998). When they viewed a bare human hand grasping objects, 7- and 12-month-old infants focused on the relation between the hand and its goal.…

  2. Incremental Contributions of FbaA and Other Impetigo-Associated Surface Proteins to Fitness and Virulence of a Classical Group A Streptococcal Skin Strain.

    Science.gov (United States)

    Rouchon, Candace N; Ly, Anhphan T; Noto, John P; Luo, Feng; Lizano, Sergio; Bessen, Debra E

    2017-11-01

    Group A streptococci (GAS) are highly prevalent human pathogens whose primary ecological niche is the superficial epithelial layers of the throat and/or skin. Many GAS strains with a strong tendency to cause pharyngitis are distinct from strains that tend to cause impetigo; thus, genetic differences between them may confer host tissue-specific virulence. In this study, the FbaA surface protein gene was found to be present in most skin specialist strains but largely absent from a genetically related subset of pharyngitis isolates. In an ΔfbaA mutant constructed in the impetigo strain Alab49, loss of FbaA resulted in a slight but significant decrease in GAS fitness in a humanized mouse model of impetigo; the ΔfbaA mutant also exhibited decreased survival in whole human blood due to phagocytosis. In assays with highly sensitive outcome measures, Alab49ΔfbaA was compared to other isogenic mutants lacking virulence genes known to be disproportionately associated with classical skin strains. FbaA and PAM (i.e., the M53 protein) had additive effects in promoting GAS survival in whole blood. The pilus adhesin tip protein Cpa promoted Alab49 survival in whole blood and appears to fully account for the antiphagocytic effect attributable to pili. The finding that numerous skin strain-associated virulence factors make slight but significant contributions to virulence underscores the incremental contributions to fitness of individual surface protein genes and the multifactorial nature of GAS-host interactions. Copyright © 2017 American Society for Microbiology.

  3. Applying tattoo dye as a third-harmonic generation contrast agent for in vivo optical virtual biopsy of human skin

    Science.gov (United States)

    Tsai, Ming-Rung; Lin, Chen-Yu; Liao, Yi-Hua; Sun, Chi-Kuang

    2013-02-01

    Third-harmonic generation (THG) microscopy has been reported to provide intrinsic contrast in elastic fibers, cytoplasmic membrane, nucleus, actin filaments, lipid bodies, hemoglobin, and melanin in human skin. For advanced molecular imaging, exogenous contrast agents are developed for a higher structural or molecular specificity. We demonstrate the potential of the commonly adopted tattoo dye as a THG contrast agent for in vivo optical biopsy of human skin. Spectroscopy and microscopy experiments were performed on cultured cells with tattoo dyes, in tattooed mouse skin, and in tattooed human skin to demonstrate the THG enhancement effect. Compared with other absorbing dyes or nanoparticles used as exogenous THG contrast agents, tattoo dyes are widely adopted in human skin so that future clinical biocompatibility evaluation is relatively achievable. Combined with the demonstrated THG enhancement effect, tattoo dyes show their promise for future clinical imaging applications.

  4. Differential susceptibility of primary cultured human skin cells to hypericin PDT in an in vitro model.

    Science.gov (United States)

    Popovic, A; Wiggins, T; Davids, L M

    2015-08-01

    Skin cancer is the most common cancer worldwide, and its incidence rate in South Africa is increasing. Photodynamic therapy (PDT) has been shown to be an effective treatment modality, through topical administration, for treatment of non-melanoma skin cancers. Our group investigates hypericin-induced PDT (HYP-PDT) for the treatment of both non-melanoma and melanoma skin cancers. However, a prerequisite for effective cancer treatments is efficient and selective targeting of the tumoral cells with minimal collateral damage to the surrounding normal cells, as it is well established that cancer therapies have bystander effects on normal cells in the body, often causing undesirable side effects. The aim of this study was to investigate the cellular and molecular effects of HYP-PDT on normal primary human keratinocytes (Kc), melanocytes (Mc) and fibroblasts (Fb) in an in vitro tissue culture model which represented both the epidermal and dermal cellular compartments of human skin. Cell viability analysis revealed a differential cytotoxic response to a range of HYP-PDT doses in all the human skin cell types, showing that Fb (LD50=1.75μM) were the most susceptible to HYP-PDT, followed by Mc (LD50=3.5μM) and Kc (LD50>4μM HYP-PDT) These results correlated with the morphological analysis which displayed distinct morphological changes in Fb and Mc, 24h post treatment with non-lethal (1μM) and lethal (3μM) doses of HYP-PDT, but the highest HYP-PDT doses had no effect on Kc morphology. Fluorescent microscopy displayed cytoplasmic localization of HYP in all the 3 skin cell types and additionally, HYP was excluded from the nuclei in all the cell types. Intracellular ROS levels measured in Fb at 3μM HYP-PDT, displayed a significant 3.8 fold (pPDT. These results depict a differential response to HYP-PDT by different human skin cells thus highlighting the efficacy and indeed, the potential bystander effect of if administered in vivo. This study contributes toward our knowledge

  5. Methacholine induces wheal-and-flare reactions in human skin but does not release histamine in vivo as assessed by the skin microdialysis technique.

    Science.gov (United States)

    Petersen, L J; Skov, P S

    1995-12-01

    A number of investigations have indicated that cholinergic agonists release histamine from isolated mast cells and suggested that cholinergic stimulation releases histamine in vivo. The purpose of this study was to investigate whether the cutaneous wheal-and-flare reaction induced by methacholine challenge in human skin involves histamine release as measured by the skin microdialysis technique. Five hollow dialysis fibers were inserted intradermally in forearm skin in eight healthy subjects. Each fiber was perfused with Kreb's-Ringer bicarbonate at a rate of 3 microliters/min. Dialysates were collected in 2-min fractions before skin challenge and for 20 min after intradermal injection of methacholine 10(-3)-10(-1) M, the vehicle, and a positive control, codeine phosphate 0.3 mg/ml. Histamine was assayed spectrofluorometrically. Methacholine caused a statistically significant dose-related wheal-and-flare reaction, the flare reaction to methacholine 10(-1) M being comparable with that seen with codeine 0.3 mg/ml. No significant histamine release was observed with methacholine, cumulative histamine release of 16 +/- 8 nM by methacholine 10(-1) M being similar to vehicle responses of 15 +/- 9 nM. Histamine release by codeine was 2524 +/- 435 nM. In conclusion, methacholine-induced wheal-and-flare reactions in human skin appeared not to involve histamine release from skin mast cells.

  6. Integration of Langerhans-like cells into a human skin equivalent.

    Science.gov (United States)

    Laubach, Vesselina; Zöller, Nadja; Rossberg, Maila; Görg, Kerstin; Kippenberger, Stefan; Bereiter-Hahn, Jürgen; Kaufmann, Roland; Bernd, August

    2011-03-01

    Studies regarding cellular interactions between Langerhans cells and other skin cells are somehow hampered by the difficult cultivation of these cells in vitro. Here, we show that the human MUTZ-3 cell line can be differentiated into Langerhans-like cells in the presence of a cytokine cocktail including GM-CSF, TGF-β1 and TNF-α. We used the expression of langerin, CD1a, CCR6 and the intracellular presence of Birbeck granules to identify the differentiated MUTZ-3 cells (MUTZ-3-LCs). The aim of this study was to integrate MUTZ-3-LCs into a three-dimensional full-thickness skin model. On top of fibroblast-containing collagen matrix a mixture of primary human keratinocytes and MUTZ-3-LCs were seeded and cultured for 24 h. Subsequently, the models were lifted up to the air-liquid interface. Histological evaluation featured a fully stratified epidermis with all characteristic epidermal strata. Langerin-positive cells were detected suprabasally within the epidermis indicating that keratinocytes provide environmental conditions for long-time maintenance of MUTZ-3-LCs. These skin models provide a tool to further investigate the interactions between Langerhans-like cells and other skin cells and particularly learn more about the cutaneous immune response.

  7. Radioprotective effects of dimethyl sulfoxide in the artificial skin reconstructed with cultured human cells

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Young Ha; Choi, Karp Shik [College of Dentistry, Kyungpook National University, Daegu (Korea, Republic of); Song, In Hwan [Department of Anatomy, College of Medicine, Yeungnam University, Daegu (Korea, Republic of)

    2002-03-15

    To evaluate cultured human artificial skin as an experimental model for studying radiation effects in vitro. The skin was constructed by culturing keratinocytes over collagen lattice which made by culturing fibroblasts. Two groups were irradiated to gamma rays at single dose of 25 Gy with or without 3.5% of DMSO. Ultrastructures were investigated by electron microscopy after irradiation. The number of epidermal layers and expression of cytokeratin (CK) 14 and 10 were also seem by light microscopy. At 2 days after irradiation in experimental group without DMSO, necrotic cells were rarely found in the spinosal layer and undercornified cells were visible in the horney layer. Similar findings were also found in experimental group with DMSO but in mild form. The number of epidermal layers in experimental group without DMSO were significantly fewer than other group. CK 14 expressed in all the layer excluding horney layer but CK 10 expressed over 3-4 basal layers. Such patterns of CK expression were similar to all groups. It is suggested that structures of the keratinocytes and epidermal formation could be disturbed by irradiation in artificial skin and that DMSO can protect these damages. Therefore this work could be used as an organotypic experimental model in vitro using human cells for studying radiation effect in skin. Furthermore structural findings provided in this study could be used as useful basic data in further study using this model.

  8. Selective susceptibility of human skin antigen presenting cells to productive dengue virus infection.

    Directory of Open Access Journals (Sweden)

    Daniela Cerny

    2014-12-01

    Full Text Available Dengue is a growing global concern with 390 million people infected each year. Dengue virus (DENV is transmitted by mosquitoes, thus host cells in the skin are the first point of contact with the virus. Human skin contains several populations of antigen-presenting cells which could drive the immune response to DENV in vivo: epidermal Langerhans cells (LCs, three populations of dermal dendritic cells (DCs, and macrophages. Using samples of normal human skin we detected productive infection of CD14(+ and CD1c(+ DCs, LCs and dermal macrophages, which was independent of DC-SIGN expression. LCs produced the highest viral titers and were less sensitive to IFN-β. Nanostring gene expression data showed significant up-regulation of IFN-β, STAT-1 and CCL5 upon viral exposure in susceptible DC populations. In mice infected intra-dermally with DENV we detected parallel populations of infected DCs originating from the dermis and migrating to the skin-draining lymph nodes. Therefore dermal DCs may simultaneously facilitate systemic spread of DENV and initiate the adaptive anti-viral immune response.

  9. Blue-light irradiation regulates proliferation and differentiation in human skin cells.

    Science.gov (United States)

    Liebmann, Joerg; Born, Matthias; Kolb-Bachofen, Victoria

    2010-01-01

    Sunlight influences the physiology of the human skin in beneficial as well as harmful ways, as has been shown for UV light. However, little is known about the effects of other wavelengths of solar irradiation. In this study we irradiated human keratinocytes and skin-derived endothelial cells with light-emitting-diode devices of distinct wavelengths to study the effects on cell physiology. We found that light at wavelengths of 632-940 nm has no effect, but irradiation with blue light at 412-426 nm exerts toxic effects at high fluences. Light at 453 nm is nontoxic up to a fluence of 500 J/cm(2). At nontoxic fluences, blue light reduces proliferation dose dependently by up to 50%, which is attributable to differentiation induction as shown by an increase of differentiation markers. Experiments with BSA demonstrate that blue-light irradiation up to 453 nm photolytically generates nitric oxide (NO) from nitrosated proteins, which is known to initiate differentiation in skin cells. Our data provide evidence for a molecular mechanism by which blue light may be effective in treating hyperproliferative skin conditions by reducing proliferation due to the induction of differentiation. We observed a photolytic release of NO from nitrosated proteins, indicating that they are light acceptors and signal transducers up to a wavelength of 453 nm.

  10. Body segment differences in surface area, skin temperature and 3D displacement and the estimation of heat balance during locomotion in hominins.

    Science.gov (United States)

    Cross, Alan; Collard, Mark; Nelson, Andrew

    2008-06-18

    The conventional method of estimating heat balance during locomotion in humans and other hominins treats the body as an undifferentiated mass. This is problematic because the segments of the body differ with respect to several variables that can affect thermoregulation. Here, we report a study that investigated the impact on heat balance during locomotion of inter-segment differences in three of these variables: surface area, skin temperature and rate of movement. The approach adopted in the study was to generate heat balance estimates with the conventional method and then compare them with heat balance estimates generated with a method that takes into account inter-segment differences in surface area, skin temperature and rate of movement. We reasoned that, if the hypothesis that inter-segment differences in surface area, skin temperature and rate of movement affect heat balance during locomotion is correct, the estimates yielded by the two methods should be statistically significantly different. Anthropometric data were collected on seven adult male volunteers. The volunteers then walked on a treadmill at 1.2 m/s while 3D motion capture cameras recorded their movements. Next, the conventional and segmented methods were used to estimate the volunteers' heat balance while walking in four ambient temperatures. Lastly, the estimates produced with the two methods were compared with the paired t-test. The estimates of heat balance during locomotion yielded by the two methods are significantly different. Those yielded by the segmented method are significantly lower than those produced by the conventional method. Accordingly, the study supports the hypothesis that inter-segment differences in surface area, skin temperature and rate of movement impact heat balance during locomotion. This has important implications not only for current understanding of heat balance during locomotion in hominins but also for how future research on this topic should be approached.

  11. Human ovarian surface epithelium in primary culture.

    Science.gov (United States)

    Auersperg, N; Siemens, C H; Myrdal, S E

    1984-10-01

    The ovarian surface epithelium (OSE) represents a minute fraction of the cell mass of the ovary but gives rise to over 80% of human ovarian carcinomas. No experimental models for the study of human OSE exist. To characterize OSE cells in culture, explants of ovarian surface from normal ovary of premenopausal women were grown on plastic, glass, and collagen gel in 25% fetal bovine serum/Waymouth's medium 752/1. About 25% of explants produced epithelial outgrowths. Morphologically, these outgrowths resembled OSE in vivo and endothelial and mesothelial cells in culture, but they differed from cultured ovarian stromal, granulosa, and luteal cells. Only OSE among ovarian cell types were intensely keratin positive by immunofluorescence. Keratin also distinguished OSE cells from the keratin-negative endothelial cells. Most but not all OSE colonies tested showed 17 beta-hydroxysteroid dehydrogenase (HSD) activity, which was absent in peritoneal mesothelial cells. Colonies from most patients were limited to a few millimetres and became stationary within a few weeks. Changes that accompanied cessation of growth included senescence, increased keratin content, or the formation of multicellular papillary aggregates. With time, OSE cells tended to assume a fibroblast-like morphology but remained keratin positive and continued to resemble OSE by scanning electron microscopy (SEM). Subcultured OSE cells persisted in a stationary keratin-positive form for many weeks. Throughout this study, all pavementlike epithelial outgrowths that were contiguous with an explant stained for keratin; thus, such colonies can be assumed to be OSE. Conversely, fibroblast-shaped cells may represent OSE as indicated by keratin content and SEM appearance. The methods presented here permit culture of normal human OSE under conditions in which the cells exhibit morphologic plasticity, variable 17 beta-HSD activity, and presence of keratin.

  12. Imaging mitochondrial dynamics in human skin reveals depth-dependent hypoxia and malignant potential for diagnosis.

    Science.gov (United States)

    Pouli, Dimitra; Balu, Mihaela; Alonzo, Carlo A; Liu, Zhiyi; Quinn, Kyle P; Rius-Diaz, Francisca; Harris, Ronald M; Kelly, Kristen M; Tromberg, Bruce J; Georgakoudi, Irene

    2016-11-30

    Active changes in mitochondrial structure and organization facilitate cellular homeostasis. Because aberrant mitochondrial dynamics are implicated in a variety of human diseases, their assessment is potentially useful for diagnosis, therapy, and disease monitoring. Because current techniques for evaluating mitochondrial morphology are invasive or necessitate mitochondria-specific dyes, their clinical translation is limited. We report that mitochondrial dynamics can be monitored in vivo, within intact human skin by relying entirely on endogenous two-photon-excited fluorescence from the reduced metabolic coenzyme nicotinamide adenine dinucleotide (NADH). We established the sensitivity of this approach with in vivo, fast temporal studies of arterial occlusion-reperfusion, which revealed acute changes in the mitochondrial metabolism and dynamics of the lower human epidermal layers. In vitro hypoxic-reperfusion studies validated that the in vivo outcomes were a result of NADH fluorescence changes. To demonstrate the diagnostic potential of this approach, we evaluated healthy and cancerous human skin epithelia. Healthy tissues displayed consistent, depth-dependent morphological and mitochondrial organization patterns that varied with histological stratification and intraepithelial mitochondrial protein expression. In contrast, these consistent patterns were absent in cancerous skin lesions. We exploited these differences to successfully differentiate healthy from cancerous tissues using a predictive classification approach. Collectively, these results demonstrate that our label-free, automated, near real-time assessments of mitochondrial organization-relying solely on endogenous contrast-could be useful for accurate, noninvasive in vivo diagnosis. Copyright © 2016, American Association for the Advancement of Science.

  13. Optical clearing of human skin for the enhancement of optical imaging of proximal interphalangeal joints

    Science.gov (United States)

    Kolesnikova, Ekaterina A.; Kolesnikov, Aleksandr S.; Zabarylo, Urszula; Minet, Olaf; Genina, Elina A.; Bashkatov, Alexey N.; Tuchin, Valery V.

    2014-01-01

    We are proposing a new method for enhancement of optical imaging of proximal interphalangeal (PIP) joints in humans at skin using optical clearing technique. A set of illuminating laser diodes with the wavelengths 670, 820, and 904 nm were used as a light source. The laser diodes, monochromatic digital CCD camera and specific software allowed for detection of the finger joint image in a transillumination mode. The experiments were carried out in vivo with human fingers. Dehydrated glycerol and hand cream with urea (5%) were used as optical clearing agents (OCAs). The contrast of the obtained images was analyzed to determine the effect of the OCA. It was found that glycerol application to the human skin during 60 min caused the decrease of contrast in 1.4 folds for 670 nm and the increase of contrast in 1.5 and 1.7 folds for 820 nm and 904 nm, respectively. At the same time, the hand cream application to the human skin during 60 min caused the decrease of contrast in 1.1 folds for 670 nm and the increase of contrast in 1.3 and 1.1 folds for 820 nm and 904 nm, respectively. The results have shown that glycerol and the hand cream with 5% urea allow for obtaining of more distinct image of finger joint in the NIR. Obtained data can be used for development of optical diagnostic methods of rheumatoid arthritis.

  14. Trifloxystrobin-induced mitophagy through mitochondrial damage in human skin keratinocytes.

    Science.gov (United States)

    Jang, Yoonjeong; Kim, Ji-Eun; Jeong, Sang-Hee; Paik, Min-Kyoung; Kim, Jun Sung; Cho, Myung-Haing

    2016-01-01

    Trifloxystrobin is a strobilurin class fungicide, the mode of action of which is to block the mitochondrial electron transport chain and inhibit energy production in fungi. Although adverse effects have been reported by occupational or environmental exposure of fungicides, the pathophysiological mechanism in human cells remains poorly understood. In the present study, we investigated the impact of trifloxystrobin on exposed skin at the cellular organelle level using HaCaT, the human skin keratinocyte cell line. Cells were treated with trifloxystrobin for 48 hr and trifloxystrobin showed detrimental effects on mitochondria evidenced by altered mitochondrial membrane potential and morphology. To identify autophagic degradation of the damaged mitochondria, confocal imaging and Western blotting were performed. Trifloxystrobin induced autophagy-related proteins in HaCaT cells. The mitochondrial reactive oxygen species scavenger mitoTEMPO was applied to further explore the mechanism of trifloxystrobin-mediated mitophagy in human skin cells. PINK1 and Parkin were overexpressed by trifloxystrobin, and mitoTEMPO alleviated the effects on mitophagy induction. Taken together, our findings indicated that mitochondrial damage and mitophagy may play a role in trifloxystrobin-induced toxicity in human keratinocytes and this could be suggested as a mechanism of cutaneous diseases developed by exposure.

  15. Isolation, identification, and pathological effects of beach sand bacterial extract on human skin keratinocytes in vitro

    Directory of Open Access Journals (Sweden)

    Fazli Subhan

    2018-01-01

    Full Text Available Background Beaches are recreational spots for people. However, beach sand contains harmful microbes that affect human health, and there are no established methods for either sampling and identifying beach-borne pathogens or managing the quality of beach sand. Method This study was conducted with the aim of improving human safety at beaches and augmenting the quality of the beach experience. Beach sand was used as a resource to isolate bacteria due to its distinctive features and the biodiversity of the beach sand biota. A selected bacterial isolate termed FSRS was identified as Pseudomonas stutzeri using 16S rRNA sequencing and phylogenetic analysis, and the sequence was deposited in the NCBI GenBank database under the accession number MF599548. The isolated P. stutzeri bacterium was cultured in Luria–Bertani growth medium, and a crude extract was prepared using ethyl acetate to examine the potential pathogenic effect of P. stutzeri on human skin. A human skin keratinocyte cell line (HaCaT was used to assess cell adhesion, cell viability, and cell proliferation using a morphological analysis and a WST-1 assay. Result The crude P. stutzeri extract inhibited cell adhesion and decreased cell viability in HaCaT cells. We concluded that the crude extract of P. stutzeri FSRS had a strong pathological effect on human skin cells. Discussion Beach visitors frequently get skin infections, but the exact cause of the infections is yet to be determined. The beach sand bacterium P. stutzeri may, therefore, be responsible for some of the dermatological problems experienced by people visiting the beach.

  16. Myelinated and unmyelinated nerve fibers reinnervate tissue-engineered dermo-epidermal human skin analogs in an in vivo model.

    Science.gov (United States)

    Biedermann, T; Klar, A S; Böttcher-Haberzeth, S; Reichmann, E; Meuli, M

    2016-12-01

    The clinical application of autologous tissue-engineered skin analogs is an important strategy to cover large skin defects. Investigating biological dynamics, such as reinnervation after transplantation, is essential to improve the quality of such skin analogs. Previously, we have examined that our skin substitutes are reinnervated by host peripheral nerve fibers as early as 8 weeks after transplantation. Here, we wanted to investigate the presence and possible differences regarding myelinated and unmyelinated host nerve fibers 15 weeks after the transplantation of light and dark human tissue-engineered skin analogs. Human epidermal keratinocytes, melanocytes, and dermal fibroblasts were isolated from human light and dark skin biopsies. Keratinocytes and melanocytes were seeded on fibroblast-containing collagen type I hydrogels after expansion in culture. After additional culturing, the tissue-engineered dermo-epidermal skin analogs were transplanted onto full-thickness skin wounds created on the back of immuno-incompetent rats. Skin substitutes were excised and analyzed 15 weeks after transplantation. Histological sections were examined with regard to the ingrowth pattern of myelinated and unmyelinated nerve fibers into the skin analogs using markers, such as Substance P, NF200, and S100-Beta. We found myelinated and unmyelinated peripheral host nerve fibers 15 weeks after transplantation in the dermal part of our human skin substitutes. In particular, we identified large-diameter-myelinated Aβ- and Aδ-fibers, and small-diameter C-fibers. Furthermore, we observed myelinated nerves in close proximity to CD31-positive blood capillaries. In the long run, both types of ingrown host fibers showed an identical pattern in both light and dark skin analogs. Our data suggest that myelinated and unmyelinated peripheral nerves reinnervate human skin substitutes in a long-term in vivo transplantation assay. Our tissue-engineered skin analogs attract A- and C-fibers to

  17. Increased Susceptibility of Humanized NSG Mice to Panton-Valentine Leukocidin and Staphylococcus aureus Skin Infection.

    Directory of Open Access Journals (Sweden)

    Ching Wen Tseng

    Full Text Available Staphylococcus aureus is a leading cause of skin and soft-tissue infections worldwide. Mice are the most commonly used animals for modeling human staphylococcal infections. However a supra-physiologic S. aureus inoculum is required to establish gross murine skin pathology. Moreover, many staphylococcal factors, including Panton-Valentine leukocidin (PVL elaborated by community-associated methicillin-resistant S. aureus (CA-MRSA, exhibit selective human tropism and cannot be adequately studied in mice. To overcome these deficiencies, we investigated S. aureus infection in non-obese diabetic (NOD/severe combined immune deficiency (SCID/IL2rγnull (NSG mice engrafted with human CD34+ umbilical cord blood cells. These "humanized" NSG mice require one to two log lower inoculum to induce consistent skin lesions compared with control mice, and exhibit larger cutaneous lesions upon infection with PVL+ versus isogenic PVL- S. aureus. Neutrophils appear important for PVL pathology as adoptive transfer of human neutrophils alone to NSG mice was sufficient to induce dermonecrosis following challenge with PVL+ S. aureus but not PVL- S. aureus. PMX53, a human C5aR inhibitor, blocked PVL-induced cellular cytotoxicity in vitro and reduced the size difference of lesions induced by the PVL+ and PVL- S. aureus, but PMX53 also reduced recruitment of neutrophils and exacerbated the infection. Overall, our findings establish humanized mice as an important translational tool for the study of S. aureus infection and provide strong evidence that PVL is a human virulence factor.

  18. The relationship between dermal papillary structure and skin surface properties, color, and elasticity.

    Science.gov (United States)

    Mizukoshi, K; Nakamura, T; Oba, A

    2016-08-01

    The skin contains an undulating structure called the dermal papillary structure between the border of the epidermis and dermis. The physiological importance of the dermal papillary structures has been discussed, however, the dermal papillary structures have never been evaluated for their contribution to skin appearance. In this study, we investigated the correlation between the dermal papillary structure and skin color and elasticity. In addition, the relationship was validated with skin model experiments. The dermal papillary structures in the skin of the female cheek were quantitatively measured by in vivo confocal laser scanning microscopy images. In addition, the skin color and elasticity were measured at the same site. A skin model with dermal papilla-like structures was created by referring to the optical and shape properties of the skin using agar gel and a scattering sheet. Correlations were found between the dermal papillary structures and skin color irregularity and skin elasticity. These relationships were verified by the experiments employing a skin model. The results of this study indicated that the dermal papillary structure is also an important factor for skin appearance such as color and elasticity. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Spatial Correlations of Anomaly Time Series of AIRS Version-6 Land Surface Skin Temperatures with the Nino-4 Index

    Science.gov (United States)

    Susskind, Joel; Lee, Jae N.; Iredell, Lena

    2013-01-01

    The AIRS Science Team Version-6 data set is a valuable resource for meteorological studies. Quality Controlled earth's surface skin temperatures are produced on a 45 km x 45 km spatial scale under most cloud cover conditions. The same retrieval algorithm is used for all surface types under all conditions. This study used eleven years of AIRS monthly mean surface skin temperature and cloud cover products to show that land surface skin temperatures have decreased significantly in some areas and increased significantly in other areas over the period September 2002 through August 2013. These changes occurred primarily at 1:30 PM but not at 1:30 AM. Cooling land areas contained corresponding increases in cloud cover over this time period, with the reverse being true for warming land areas. The cloud cover anomaly patterns for a given month are affected significantly by El Nino/La Nina activity, and anomalies in cloud cover are a driving force behind anomalies in land surface skin temperature.

  20. The validity of wireless iButtons and thermistors for human skin temperature measurement.

    Science.gov (United States)

    Smith, A D Harper; Crabtree, D R; Bilzon, J L J; Walsh, N P

    2010-01-01

    Skin temperature is a fundamental variable in human thermo-physiology, and yet skin temperature measurement remains impractical in most free-living, exercise and clinical settings, using currently available hard-wired methods. The purpose of this study was to compare wireless iButtons and hard-wired thermistors for human skin temperature measurement. In the first of two investigations, iButtons and thermistors monitored temperature in a controlled water bath (range: 10-40 degrees C) and were referenced against a certified, mercury thermometer. In the second investigation, eight healthy males completed three randomized trials (ambient temperature = 10 degrees C, 20 degrees C and 30 degrees C) while both devices recorded skin temperature at rest (in low and high wind velocities) and during cycle-ergometry exercise. The results are as follows. Investigation 1: both devices displayed very high validity correlation with the reference thermometer (r > 0.999). Prior to correction, the mean bias was +0.121 degrees C for iButtons and +0.045 degrees C for thermistors. Upon calibration correction the mean bias for iButtons and thermistors was not significantly different from zero bias. Interestingly, a typical error of the estimate of iButtons (0.043 degrees C) was 1.5 times less than that of thermistors (0.062 degrees C), demonstrating iButtons' lower random error. Investigation 2: the offset between iButton and thermistor readings was generally consistent across conditions; however, thermistor responses gave readings that were always closer to ambient temperature than those given by iButtons, suggesting potential thermistor drift towards environmental conditions. Mean temperature differences between iButtons and thermistors during resting trials ranged from 0.261 degrees C to 1.356 degrees C. Mean temperature differences between iButtons and thermistors during exercise were 0.989 degrees C (ambient temperature = 10 degrees C), 0.415 degrees C (ambient temperature = 20

  1. Comparison of the Prevalences of Demodex folliculorum in Rosacea and Seborrhoeic Dermatitis with Standardized Skin Surface Biopsy

    Directory of Open Access Journals (Sweden)

    B Tas

    2015-09-01

    Full Text Available Objective: Rosacea (RSC and seborrhoeic dermatitis (SD are inflammatory dermatological conditions which are located in sebaceous gland-rich areas. Demodex folliculorum (D folliculorum is the most common ectoparasite in humans that may play a role in the aetiopathogenesis of both diseases. The aims of this study were to compare the prevalences of D folliculorum positivity in patients with RSC and SD; compare the positivity in both diseases according to different age ranges and gender and compare mite positivity according to clinical types of RSC. Methods: A total of 200 facial skin biopsies, one from each patient clinically diagnosed as RSC (100 patients and as SD (100 patients were studied between February 2011 and August 2013. D folliculorum density was investigated using standardized skin surface biopsy and the specimens were examined under light microscope. Quantitative data were tested withPearson’s Chi-squared test and Fisher’s exact test,andsignificance was defined as a p-value of < 0.05. Results: Demodex mite was positive in 51 (25.50% of the 200 patients (74.51% of them had RSC, and 25.49% had SD; p = 0.0001. No statistical differences were detected between the prevalences of Demodex positivity in patients with RSC in terms of gender (p = 0.768 and age (p = 0.193. In the SD group, there was no statistical difference in mite positivity in terms of gender (p = 0.138, while the positivity was significantly higher in the age group 45 years and over (p = 0.039. In different clinical types of RSC, there was no significant difference with respect to mite positivity (p = 0.168. Conclusion: Positivity of D folliculorum was significantly higher in RSC when compared to SD. Our results suggest that D folliculorum mite can play a more important role in the aetiopathogenesis of RSC than SD.

  2. Assimilation of Satellite-Derived Skin Temperature Observations into Land Surface Models

    Science.gov (United States)

    Reichle, Rolf H.; Kumar, Sujay V.; Mahanama, P. P.; Koster, Randal D.; Liu, Q.

    2010-01-01

    Land surface (or "skin") temperature (LST) lies at the heart of the surface energy balance and is a key variable in weather and climate models. Here we assimilate LST retrievals from the International Satellite Cloud Climatology Project (ISCCP) into the Noah and Catchment (CLSM) land surface models using an ensemble-based, off-line land data assimilation system. LST is described very differently in the two models. A priori scaling and dynamic bias estimation approaches are applied because satellite and model LST typically exhibit different mean values and variability. Performance is measured against 27 months of in situ measurements from the Coordinated Energy and Water Cycle Observations Project at 48 stations. LST estimates from Noah and CLSM without data assimilation ("open loop") are comparable to each other and superior to that of ISCCP retrievals. For LST, RMSE values are 4.9 K (CLSM), 5.6 K (Noah), and 7.6 K (ISCCP), and anomaly correlation coefficients (R) are 0.62 (CLSM), 0.61 (Noah), and 0.52 (ISCCP). Assimilation of ISCCP retrievals provides modest yet statistically significant improvements (over open loop) of up to 0.7 K in RMSE and 0.05 in anomaly R. The skill of surface turbulent flux estimates from the assimilation integrations is essentially identical to the corresponding open loop skill. Noah assimilation estimates of ground heat flux, however, can be significantly worse than open loop estimates. Provided the assimilation system is properly adapted to each land model, the benefits from the assimilation of LST retrievals are comparable for both models.

  3. The vasorelaxant effect of adrenomedullin, proadrenomedullin N-terminal 20 peptide and amylin in human skin

    DEFF Research Database (Denmark)

    Hasbak, Philip; Eskesen, Karen; Lind, Peter Henrik

    2006-01-01

    In this study we aimed to assess in vivo, the vasodilator effects of adrenomedullin, proadrenomedullin N-terminal 20 peptide (PAMP) and amylin in human skin vasculature and compare the responses to the effects mediated by the endogenous neuropeptides calcitonin gene-related peptide (CGRP......) and substance P and to examine the mRNA expression of calcitonin receptor-like receptor (CL-R) and receptor-activity modifying proteins, RAMP1, RAMP 2 and RAMP3 in human subcutaneous arteries. Changes in skin blood flow of the forearm were measured using a Laser Doppler Imager after intradermal injection...... to the transient response induced by substance P. PAMP (10(-6)-10(-5) M) caused distinct itch sensation and local erythema. This effect could be abolished when combining the histamine H1-receptor antagonist mepyramin and PAMP. Real-time PCR data showed a higher level of mRNA for RAMP2 than CL-R, RAMP1 and RAMP3...

  4. Organelle-specific injury to melanin-containing cells in human skin by pulsed laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, G.F.; Shepard, R.S.; Paul, B.S.; Menkes, A.; Anderson, R.R.; Parrish, J.A.

    1983-12-01

    Physical models predict that ultraviolet laser radiation of appropriately brief pulses can selectively alter melanin-containing cellular targets in human skin. Skin of normal human volunteers was exposed to brief (20 nanosecond) 351-nm wave length pulses from a XeF excimer laser, predicting that those cells containing the greatest quantities of melanized melanosomes (lower half of the epidermis) would be selectively damaged. Transmission electron microscopy revealed the earliest cellular alteration to be immediate disruption of melanosomes, both within melanocytes and basal keratinocytes. This disruption was dose dependent and culminated in striking degenerative changes in these cells. Superficial keratinocytes and Langerhans cells were not affected. It was concluded that the XeF excimer laser is capable of organelle-specific injury to melanosomes. These findings may have important clinical implications in the treatment of both benign and malignant pigmented lesions by laser radiations of defined wave lengths and pulse durations.

  5. Microdialysis of the interstitial water space in human skin in vivo

    DEFF Research Database (Denmark)

    Petersen, L J; Kristensen, J K; Bülow, J

    1992-01-01

    The purpose of this study was to evaluate the usefulness of a microdialysis technique for measurement of substances in the interstitial water space in intact human skin. Glucose was selected to validate the method. The cutaneous glucose concentration was measured by microdialysis and compared...... of the dialysis probes was established by C-mode ultrasound scanning. The implantation trauma lasted 90-135 min as measured by laser Doppler flowmetry. Each dialysis fiber was calibrated in vivo by perfusing it with four to five different glucose concentrations. The perfusion rate was 3 microliters...... that the microdialysis technique accurately and precisely can reflect biochemical events in the interstitial water space in human skin in vivo....

  6. Development of a three-dimensional surface imaging system for melanocytic skin lesion evaluation.

    Science.gov (United States)

    Tosca, Androniki; Kokolakis, Athanasios; Lasithiotakis, Konstantinos; Zacharopoulos, Athanasios; Zabulis, Xenophon; Marnelakis, Ioannis; Ripoll, Jorge; Stephanidis, Constantine

    2013-01-01

    Even though surface morphology is always taken into account when assessing clinically pigmented skin lesions, it is not captured by most modern imaging systems using digital imaging. Our aim is to develop a novel three-dimensional (3D) imaging technique to record detailed information of the surface anatomy of melanocytic lesions that will enable improved classification through digital imaging. The apparatus consists of three high-resolution cameras, a light source, and accompanying software. Volume measurements of specific phantoms using volumetric tubes render slightly lower values than those obtained by our 3D imaging system (mean%± SD, 3.8%± 0.98, Pimaging of melanocytic lesions is carried out. The mean%± SD differences of area, major axis length, volume, and maximum height are 2.1%± 1.1, 0.9%± 0.8, 3.8%± 2.9, and 2.5%± 3.5, respectively. Thirty melanocytic lesions are assessed, including common and dysplastic nevi and melanomas. There is a significant difference between nevi and melanomas in terms of variance in height and boundary asymmetry (P<0.001). Moreover, dysplastic nevi have significantly higher variances in pigment density values than common nevi (P<0.001). Preliminary data suggest that our instrument has great potential in the evaluation of the melanocytic lesions. However, these findings should be confirmed in larger-scale studies.

  7. Development of a three-dimensional surface imaging system for melanocytic skin lesion evaluation

    Science.gov (United States)

    Tosca, Androniki; Kokolakis, Athanasios; Lasithiotakis, Konstantinos; Zacharopoulos, Athanasios; Zabulis, Xenophon; Marnelakis, Ioannis; Ripoll, Jorge; Stephanidis, Constantine

    2013-01-01

    Even though surface morphology is always taken into account when assessing clinically pigmented skin lesions, it is not captured by most modern imaging systems using digital imaging. Our aim is to develop a novel three-dimensional (3D) imaging technique to record detailed information of the surface anatomy of melanocytic lesions that will enable improved classification through digital imaging. The apparatus consists of three high-resolution cameras, a light source, and accompanying software. Volume measurements of specific phantoms using volumetric tubes render slightly lower values than those obtained by our 3D imaging system (mean%±SD, 3.8%±0.98, Plesions is carried out. The mean%±SD differences of area, major axis length, volume, and maximum height are 2.1%±1.1, 0.9%±0.8, 3.8%±2.9, and 2.5%±3.5, respectively. Thirty melanocytic lesions are assessed, including common and dysplastic nevi and melanomas. There is a significant difference between nevi and melanomas in terms of variance in height and boundary asymmetry (Ppigment density values than common nevi (Plesions. However, these findings should be confirmed in larger-scale studies.

  8. Tactile surface classification for limbed robots using a pressure sensitive robot skin.

    Science.gov (United States)

    Shill, Jacob J; Collins, Emmanuel G; Coyle, Eric; Clark, Jonathan

    2015-02-02

    This paper describes an approach to terrain identification based on pressure images generated through direct surface contact using a robot skin constructed around a high-resolution pressure sensing array. Terrain signatures for classification are formulated from the magnitude frequency responses of the pressure images. The initial experimental results for statically obtained images show that the approach yields classification accuracies [Formula: see text]. The methodology is extended to accommodate the dynamic pressure images anticipated when a robot is walking or running. Experiments with a one-legged hopping robot yield similar identification accuracies [Formula: see text]. In addition, the accuracies are independent with respect to changing robot dynamics (i.e., when using different leg gaits). The paper further shows that the high-resolution capabilities of the sensor enables similarly textured surfaces to be distinguished. A correcting filter is developed to accommodate for failures or faults that inevitably occur within the sensing array with continued use. Experimental results show using the correcting filter can extend the effective operational lifespan of a high-resolution sensing array over 6x in the presence of sensor damage. The results presented suggest this methodology can be extended to autonomous field robots, providing a robot with crucial information about the environment that can be used to aid stable and efficient mobility over rough and varying terrains.

  9. Validation of Surface Skin Temperature and Moisture Profiles Using Satellite Data

    Science.gov (United States)

    Wu, Man Li C.; Schubert, Siegfried; Lin, Ching I.

    1999-01-01

    New validation techniques and metrics using satellite data have been developed to evaluate the quality of model-based estimates of surface skin temperature (Tg) and moisture profiles (q). The satellite data consist of clear sky outgoing long-wave radiation (CLR), broadband radiances from 8 to 12 mu (RadWn), brightness temperature centered around 10.8 mu (Tbb), and total precipitable water (TPW) from microwave radiometry. We show that CLR can be used to diagnose Tg. Furthermore, by using a combination of CLR and RadWn from CERES-TRMM measurements and TPW from SSM/I, we are able to identify errors in the moisture profile. Finally, three-hourly Tbb from the International Satellite Cloud Climatology Project can be used to evaluate the amplitude and diurnal variation of Tg. For purpose of illustration, Tg and q are evaluated from runs with an early version of the Goddard Earth Observing System Data Assimilation System (GEOS-2). It is found that, in general, Tg is too cold in the winter hemisphere and q is too wet in the upper atmosphere. In order to address these deficiencies, several improvements have been implemented into GEOS-2, including a Land-Surface-Model, a Moist Turbulence Scheme, and the assimilation of new TOVS retrievals. Preliminary results indicate positive impacts from each of these implementations.

  10. Improving the Accuracy of Satellite Sea Surface Temperature Measurements by Explicitly Accounting for the Bulk-Skin Temperature Difference

    Science.gov (United States)

    Castro, Sandra L.; Emery, William J.

    2002-01-01

    The focus of this research was to determine whether the accuracy of satellite measurements of sea surface temperature (SST) could be improved by explicitly accounting for the complex temperature gradients at the surface of the ocean associated with the cool skin and diurnal warm layers. To achieve this goal, work centered on the development and deployment of low-cost infrared radiometers to enable the direct validation of satellite measurements of skin temperature. During this one year grant, design and construction of an improved infrared radiometer was completed and testing was initiated. In addition, development of an improved parametric model for the bulk-skin temperature difference was completed using data from the previous version of the radiometer. This model will comprise a key component of an improved procedure for estimating the bulk SST from satellites. The results comprised a significant portion of the Ph.D. thesis completed by one graduate student and they are currently being converted into a journal publication.

  11. Titanium Dioxide Nanoparticles are not Cytotoxic or Clastogenic in Human Skin Cells

    OpenAIRE

    Browning, Cynthia L; The, Therry; Mason, Michael D; Wise, John Pierce

    2014-01-01

    The application of nanoparticle technology is rapidly expanding. The reduced dimensionality of nanoparticles can give rise to changes in chemical and physical properties, often resulting in altered toxicity. People are exposed dermally to titanium dioxide (TiO2) nanoparticles in industrial and residential settings. The general public is increasingly exposed to these nanoparticles as their use in cosmetics, sunscreens and lotions expands. The toxicity of TiO2 nanoparticles towards human skin c...

  12. Topographical distribution of pinprick and warmth thresholds to CO2 laser stimulation on the human skin

    DEFF Research Database (Denmark)

    Agostino, R.; Cruccu, G.; Iannetti, G.

    2000-01-01

    We studied the topographical distribution of laser sensory thresholds on the human hairy skin, using a small laser beam for pinprick and a large beam for warmth sensations. The threshold for pinprick sensation correlated positively with the distance from the brain, suggesting that A delta....... Possibly because of a diffuse low density of warmth receptors, laser warmth thresholds showed no trend. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved....

  13. Autophagic-lysosomal dysregulation downstream of cathepsin B inactivation in human skin fibroblasts exposed to UVA

    OpenAIRE

    Lamore, Sarah D.; Wondrak, Georg T.

    2011-01-01

    Recently, using 2D-DIGE proteomics we have identified cathepsin B as a novel target of UVA in human Hs27 skin fibroblasts. In response to chronic exposure to noncytotoxic doses of UVA (9.9 J/cm2, twice a week, 3 weeks), photooxidative impairment of cathepsin B enzymatic activity occurred with accumulation of autofluorescent aggregates colocalizing with lysosomes, an effect mimicked by pharmacological antagonism of cathepsin B using the selective inhibitor CA074Me. Here, we have further explor...

  14. Sensory responses of human skin to synthetic histamine analogues and histamine.

    OpenAIRE

    Davies, M.G.; Greaves, M W

    1980-01-01

    The potential for itch production in human skin of the synthetic analogues of histamine, 2-methyl histamine (an H1-receptor agonist) and 4-methyl histamine and dimaprit (H2-receptor agonists) has been studied in vivo and compared with histamine. Itch thresholds for 2-methyl histamine were consistently much higher than for histamine (P < 0.001). The H1-receptor antagonist chlorpheniramine raised the itch thresholds to 2-methyl histamine and histamine significantly (P < 0.001). Pruritus was not...

  15. Influence of caffeine and hyaluronic acid on collagen biosynthesis in human skin fibroblasts

    Directory of Open Access Journals (Sweden)

    Donejko M

    2014-10-01

    Full Text Available Magdalena Donejko,1 Andrzej Przylipiak,1 Edyta Rysiak,2 Katarzyna Głuszuk,2 Arkadiusz Surażyński2 1Department of Esthetic Medicine, 2Department of Medicinal Chemistry, Faculty of Pharmacy, Medical University of Białystok, Białystok, Poland Aim: The aim of this study was to evaluate the effect of caffeine on collagen biosynthesis in human skin fibroblasts and the influence of hyaluronic acid (HA on this process. Materials and methods: Collagen, [3H]-thymidine incorporation, and prolidase activity were measured in confluent human skin fibroblast cultures that had been treated with 1, 2, and 5 mM caffeine and with caffeine and 500 µg/mL HA. Western immunoblot analysis was performed to evaluate expression of ß1-integrin receptor, insulin-like growth factor receptor phospho-Akt protein and mitogen-activated protein kinase (phospho-extracellular signal-regulated kinase. Results: Caffeine inhibited collagen biosynthesis in a dose-dependent manner. The mechanism of this process was found at the level of prolidase activity. Caffeine significantly inhibited the enzyme activity. The addition of HA had no effect on collagen biosynthesis or prolidase activity in fibroblasts incubated with caffeine. Caffeine also had an inhibitory effect on DNA biosynthesis. HA, however, did not have any significant effect on this process. The inhibition of the expression of ß1-integrin and insulin-like growth factor receptor in fibroblasts incubated with the caffeine indicates a possible mechanism of inhibition of collagen biosynthesis. Conclusion: Caffeine reduces collagen synthesis in human cultured skin fibroblasts. HA did not have any significant protective effect on this process. This is the first study to our knowledge that reports caffeine-induced inhibition of collagen synthesis in human skin fibroblasts. Keywords: collagen, caffeine, hyaluronic acid, fibroblast

  16. Targeting of eugenol-loaded solid lipid nanoparticles to the epidermal layer of human skin.

    Science.gov (United States)

    Garg, Anuj; Singh, Sanjay

    2014-01-01

    The purpose of this study was to formulate carbopol hydrogels containing eugenol-loaded solid lipid nanoparticles (EG-SLNs) for epidermal targeting to treat fungal infections in skin. EG-SLNs were incorporated into carbopol hydrogels and the physiochemical characteristics of EG-SLN in hydrogels were investigated by dynamic light scattering, transmission electron microscopy and atomic force microscopy. Rheological behavior and mechanical properties of hydrogels were also studied before and after incorporation of EG-SLNs. The epidermal-targeting ability of EG-SLN-enriched hydrogels was ev