Science.gov

Sample records for human skin in-vivo

  1. Multiphoton spectroscopy of human skin in vivo

    NASA Astrophysics Data System (ADS)

    Breunig, Hans G.; Weinigel, Martin; König, Karsten

    2012-03-01

    In vivo multiphoton-intensity images and emission spectra of human skin are reported. Optical sections from different depths of the epidermis and dermis have been measured with near-infrared laser-pulse excitation. While the intensity images reveal information on the morphology, the spectra show emission characteristics of main endogenous skin fluorophores like keratin, NAD(P)H, melanin, elastin and collagen as well as of second harmonic generation induced by the excitation-light interaction with the dermal collagen network.

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

    PubMed

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

    2013-12-01

    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 the human skin, subject characteristics and environmental conditions on skin friction. The data are obtained on 50 subjects (34 males and 16 females). Friction measurements represent the friction between in vivo human skin and an aluminium sample, assessed on three anatomical locations. The coefficient of friction increased significantly (p<0.05) with increasing age, increasing ambient temperature and increasing relative air humidity. A significant inversely proportional relationship was found between friction and both the amount of hair present on the skin and the height of the subject. Other outcome variables in this study were the hydration of the skin and the skin temperature.

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

    NASA Astrophysics Data System (ADS)

    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.

  4. In vivo optical coherence tomography of human skin microstructure

    NASA Astrophysics Data System (ADS)

    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.

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

    NASA Astrophysics Data System (ADS)

    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

  6. Spectral characteristics of two-photon autofluorescence and second harmonic generation from human skin in vivo

    NASA Astrophysics Data System (ADS)

    Breunig, Hans G.; König, Karsten

    2011-03-01

    We performed multiphoton imaging of human skin and recorded in combination the complete spectral content of the signals in vivo. The spectra represent the integration of multiphoton signals over the investigated regions of the epidermis and dermis. They are used to study depth-resolved in vivo emission characteristics of main endogenous skin fluorophores like keratin, NAD(P)H, collagen and elastin. The identification of the specific fluorophores is supported by analysis of additional in vivo fluorescence lifetime imaging. Furthermore, as a potential application of spectrally selective imaging the possibility to investigate the penetration of nanoparticles from sunscreen lotion into skin in vivo is discussed.

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

    NASA Astrophysics Data System (ADS)

    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.

  8. Contribution to the Determination of In Vivo Mechanical Characteristics of Human Skin by Indentation Test

    PubMed Central

    Zahouani, Hassan

    2013-01-01

    This paper proposes a triphasic model of intact skin in vivo based on a general phenomenological thermohydromechanical and physicochemical (THMPC) approach of heterogeneous media. The skin is seen here as a deforming stratified medium composed of four layers and made out of different fluid-saturated materials which contain also an ionic component. All the layers are treated as linear, isotropic materials described by their own behaviour law. The numerical simulations of in vivo indentation test performed on human skin are given. The numerical results correlate reasonably well with the typical observations of indented human skin. The discussion shows the versatility of this approach to obtain a better understanding on the mechanical behaviour of human skin layers separately. PMID:24324525

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

    NASA Astrophysics Data System (ADS)

    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.

  10. In vivo confocal Raman spectroscopy study of the vitamin A derivative perfusion through human skin

    NASA Astrophysics Data System (ADS)

    dos Santos, Laurita; Téllez Soto, Claudio A.; Favero, Priscila P.; Martin, Airton A.

    2016-03-01

    In vivo confocal Raman spectroscopy is a powerful non-invasive technique able to analyse the skin constituents. This technique was applied to transdermal perfusion studies of the vitamin A derivative in human skin. The composition of the stratum corneum (lipid bilayer) is decisive for the affinity and transport of the vitamin through skin. The vitamin A is significantly absorbed by human skin when applied with water in oil emulsion or hydro-alcoholic gel. The purpose of this study is to elucidate the behaviour of vitamin A derivative into human skin without the presence of enhancers. The results showed that the intensity band of the derivative (around 1600 cm-1), which represents the -C=O vibrational mode, was detected in different stratum corneum depths (up to 20 μm). This Raman peak of vitamin A derivative has non-coincident band with the Raman spectra of the skin epidermis, demonstrating that compound penetrated in forearm skin.

  11. Dynamic in vivo mapping of model moisturiser ingress into human skin by GARfield MRI.

    PubMed

    Ciampi, Elisabetta; van Ginkel, Michael; McDonald, Peter J; Pitts, Simon; Bonnist, Eleanor Y M; Singleton, Scott; Williamson, Ann-Marie

    2011-02-01

    We describe the development of in vivo one-dimensional MRI (profiling) using a GARField (Gradient At Right angles to Field) magnet for the characterisation of side-of-hand human skin. For the first time and in vivo, we report measurements of the NMR longitudinal and transverse relaxation parameters and self-diffusivity of the upper layers of human skin with a nominal spatial resolution better than 10 µm. The results are correlated with in vivo confocal Raman spectroscopy measurements of water concentration and natural moisturiser factors, and discussed in terms of known skin biology and microstructure of the stratum corneum and viable epidermis. The application of model moisturiser solutions to the skin is followed and their dynamics of ingress are characterised using the MRI methodology developed. Selected hydrophilic and lipophilic formulations are studied. The results are corroborated by standard in vivo measurements of transepidermal water loss and hydration status. A further insight into moisturisation mechanisms is gained. The effect of two different penetration enhancers on a commonly used skin care oil is also discussed, and different timescales of oil penetration into the skin are reported depending on the type of enhancer.

  12. In vitro and in vivo study of dye diffusion into the human skin and hair follicles.

    PubMed

    Genina, Elina A; Bashkatov, Alexey N; Sinichkin, Yury P; Kochubey, Vyacheslav I; Lakodina, Nina A; Altshuler, Gregory B; Tuchin, Valery V

    2002-07-01

    We present experimental results on the in vitro and in vivo study of dye diffusion into human skin and hair follicles. We have studied some commercially available dyes for potential using in the laser selective thermolysis. The degree and the depth of hair follicle dyeing inside the skin were determined. For hairs in different stages the sebaceous gland was stated as a reservoir for a dye administration. It was found that the penetration depth of dyes is about 1.2 mm from the skin surface. We have developed the biocompatible Indocyanine Green lotions and the method for in vivo dyeing and dye in depth monitoring. Shift on 16-21 nm of absorption peak of Indocyanine Green to the longer wavelengths due to Indocyanine Green binding with cell proteins in the human skin was found.

  13. OCT-based label-free in vivo lymphangiography within human skin and areola

    PubMed Central

    Baran, Utku; Qin, Wan; Qi, Xiaoli; Kalkan, Goknur; Wang, Ruikang K.

    2016-01-01

    Due to the limitations of current imaging techniques, visualization of lymphatic capillaries within tissue in vivo has been challenging. Here, we present a label-free high resolution optical coherence tomography (OCT) based lymphangiography (OLAG) within human skin in vivo. OLAG enables rapid (~seconds) mapping of lymphatic networks, along with blood vessel networks, over 8 mm x 8 mm of human skin and 5 mm x 5 mm of human areola. Moreover, lymphatic system’s response to inflammation within human skin is monitored throughout an acne lesion development over 7 days. The demonstrated results promise OLAG as a revolutionary tool in the clinical research and treatment of patients with pathologic conditions such as cancer, diabetes, and autoimmune diseases. PMID:26892830

  14. OCT-based label-free in vivo lymphangiography within human skin and areola

    NASA Astrophysics Data System (ADS)

    Baran, Utku; Qin, Wan; Qi, Xiaoli; Kalkan, Goknur; Wang, Ruikang K.

    2016-02-01

    Due to the limitations of current imaging techniques, visualization of lymphatic capillaries within tissue in vivo has been challenging. Here, we present a label-free high resolution optical coherence tomography (OCT) based lymphangiography (OLAG) within human skin in vivo. OLAG enables rapid (~seconds) mapping of lymphatic networks, along with blood vessel networks, over 8 mm x 8 mm of human skin and 5 mm x 5 mm of human areola. Moreover, lymphatic system’s response to inflammation within human skin is monitored throughout an acne lesion development over 7 days. The demonstrated results promise OLAG as a revolutionary tool in the clinical research and treatment of patients with pathologic conditions such as cancer, diabetes, and autoimmune diseases.

  15. Application of the front detection photopiroelectric configuration to the study of in vivo human skin

    NASA Astrophysics Data System (ADS)

    Gutierrez-Juarez, G.; Pichardo-Molina, J. L.; Rocha-Osornio, L. N.; Huerta-Franco, R.; Ivanov, R.; Huerta-Franco, B.; Cordova-Fraga, T.; Vargas-Luna, M.

    2005-06-01

    We report a novel method for measurements in vivo of the penetration of topically applied substances by inverse photopyroelectric configuration. This configuration was used to obtain the thermal effusivity, as a function of time, of in vivo human skin with ointments. This thermal magnitude was employed to characterize the penetration on the anterior-face of the volunteers forearm. This thermal effusivity was fitted with an exponential function in order to obtain a parameter (characteristic time) for the penetration. The substances used were a sunscreen and Vick Vaporub ointment. We found that the sunscreen have a characteristic time bigger that the Vick Vaporub ointment. The feasibility of skin hydration studies are discussed.

  16. Biomechanical properties of in vivo human skin from dynamic optical coherence elastography.

    PubMed

    Liang, Xing; Boppart, Stephen A

    2010-04-01

    Dynamic optical coherence elastography is used to determine in vivo skin biomechanical properties based on mechanical surface wave propagation. Quantitative Young's moduli are measured on human skin from different sites, orientations, and frequencies. Skin thicknesses, including measurements from different layers, are also measured simultaneously. Experimental results show significant differences among measurements from different skin sites, between directions parallel and orthogonal to Langer's lines, and under different skin hydration states. Results also suggest surface waves with different driving frequencies represent skin biomechanical properties from different layers in depth. With features such as micrometer-scale resolution, noninvasive imaging, and real-time processing from the optical coherence tomography technology, this optical measurement technique has great potential for measuring skin biomechanical properties in dermatology.

  17. Image segmentation for integrated multiphoton microscopy and reflectance confocal microscopy imaging of human skin in vivo

    PubMed Central

    Chen, Guannan; Lui, Harvey

    2015-01-01

    Background Non-invasive cellular imaging of the skin in vivo can be achieved in reflectance confocal microscopy (RCM) and multiphoton microscopy (MPM) modalities to yield complementary images of the skin based on different optical properties. One of the challenges of in vivo microscopy is the delineation (i.e., segmentation) of cellular and subcellular architectural features. Methods In this work we present a method for combining watershed and level-set models for segmentation of multimodality images obtained by an integrated MPM and RCM imaging system from human skin in vivo. Results Firstly, a segmentation model based on watershed is introduced for obtaining the accurate structure of cell borders from the RCM image. Secondly,, a global region based energy level-set model is constructed for extracting the nucleus of each cell from the MPM image. Thirdly, a local region-based Lagrange Continuous level-set approach is used for segmenting cytoplasm from the MPM image. Conclusions Experimental results demonstrated that cell borders from RCM image and boundaries of cytoplasm and nucleus from MPM image can be obtained by our segmentation method with better accuracy and effectiveness. We are planning to use this method to perform quantitative analysis of MPM and RCM images of in vivo human skin to study the variations of cellular parameters such as cell size, nucleus size and other mophormetric features with skin pathologies. PMID:25694949

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

    NASA Astrophysics Data System (ADS)

    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.

  19. In vivo multiphoton microscopy associated to 3D image processing for human skin characterization

    NASA Astrophysics Data System (ADS)

    Baldeweck, T.; Tancrède, E.; Dokladal, P.; Koudoro, S.; Morard, V.; Meyer, F.; Decencière, E.; Pena, A.-M.

    2012-03-01

    Multiphoton microscopy has emerged in the past decade as a promising non-invasive skin imaging technique. The aim of this study was to assess whether multiphoton microscopy coupled to specific 3D image processing tools could provide new insights into the organization of different skin components and their age-related changes. For that purpose, we performed a clinical trial on 15 young and 15 aged human female volunteers on the ventral and dorsal side of the forearm using the DermaInspectR medical imaging device. We visualized the skin by taking advantage of intrinsic multiphoton signals from cells, elastic and collagen fibers. We also developed 3D image processing algorithms adapted to in vivo multiphoton images of human skin in order to extract quantitative parameters in each layer of the skin (epidermis and superficial dermis). The results show that in vivo multiphoton microscopy is able to evidence several skin alterations due to skin aging: morphological changes in the epidermis and modifications in the quantity and organization of the collagen and elastic fibers network. In conclusion, the association of multiphoton microscopy with specific image processing allows the three-dimensional organization of skin components to be visualized and quantified thus providing a powerful tool for cosmetic and dermatological investigations.

  20. Excision repair of UV-induced pyrimidine dimers in human skin in vivo

    SciTech Connect

    D'Ambrosio, S.M.; Slazinski, L.; Whetstone, J.W.; Lowney, E.

    1981-09-01

    The induction and loss of pyrimidine dimers in human skin in vivo was determined using UV endonuclease, alkaline sucrose sedimentations, and the fluorescent detection of nonradiolabeled DNA. The number of dimers induced following exposure of the skin to radiation emitted from a Burdick UV-800 sunlamp was quantitated by reacting the extracted DNA with Micrococcus luteus endonuclease specific for pyrimidine dimers. Exposure to 15 and 30 seconds of radiation emitted from this lamp produced the formation of 12.8 and 23.6 dimers per 10(8) daltons DNA, respectively. Approximately 50% of the dimers induced were lost 58 min after irradiation. Only a small percentage (less than 10) remained 24 hr postirradiation. These data partially characterize the process by which pyrimidine dimers are excised from human skin DNA in vivo.

  1. Imaging of zinc oxide nanoparticle penetration in human skin in vitro and in vivo.

    PubMed

    Zvyagin, Andrei V; Zhao, Xin; Gierden, Audrey; Sanchez, Washington; Ross, Justin A; Roberts, Michael S

    2008-01-01

    Zinc oxide (ZnO-nano) and titanium dioxide nanoparticles (20 to 30 nm) are widely used in several topical skin care products, such as sunscreens. However, relatively few studies have addressed the subdermal absorption of these nanoparticles in vivo. We report on investigation of the distribution of topically applied ZnO in excised and in vivo human skin, using multiphoton microscopy (MPM) imaging with a combination of scanning electron microscopy (SEM) and an energy-dispersive x-ray (EDX) technique to determine the level of penetration of nanoparticles into the sub-dermal layers of the skin. The good visualization of ZnO in skin achieved appeared to result from two factors. First, the ZnO principal photoluminescence at 385 nm is in the "quiet" spectral band of skin autofluorescence dominated by the endogenous skin fluorophores, i.e., NAD[P]H and FAD. Second, the two-photon action cross section of ZnO-nano [sigma(ZnO) ((TPEF)) approximately 0.26 GM; diameter, 18 nm] is high: approximately 500-fold of that inferred from its bulk third-order nonlinear susceptibility [Im chi(ZnO) ((3))], and is favorably compared to that of NAD[P]H and FAD. The overall outcome from MPM, SEM, and EDX studies was that, in humans in vivo, ZnO nanoparticles stayed in the stratum corneum (SC) and accumulated into skin folds and/or hair follicle roots of human skin. Given the lack of penetration of these nanoparticles past the SC and that the outermost layers of SC have a good turnover rate, these data suggest that the form of ZnO-nano studied here is unlikely to result in safety concerns.

  2. Impact of Humidity on In Vitro Human Skin Permeation Experiments for Predicting In Vivo Permeability.

    PubMed

    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.

  3. In vivo measurement of mid-infrared light scattering from human skin

    PubMed Central

    Michel, Anna P. M.; Liakat, Sabbir; Bors, Kevin; Gmachl, Claire F.

    2013-01-01

    Two mid-infrared light sources, a broadband source from a Fourier Transform Infrared Spectrometer (FTIR) and a pulsed Quantum Cascade (QC) Laser, are used to measure angle-resolved backscattering in vivo from human skin across a broad spectral range. Scattering profiles measured using the FTIR suggest limited penetration of the light into the skin, with most of the light interacting with the stratum corneum layer of the epidermis. Scattering profiles from the QC laser show modulation patterns with angle suggesting interaction with scattering centers in the skin. The scattering is attributed to interaction of the laser light with components such as collagen fibers and capillaries in the dermis layer of the skin. PMID:23577287

  4. Pituitary adenylate cyclase activating polypeptide: an important vascular regulator in human skin in vivo.

    PubMed

    Seeliger, Stephan; Buddenkotte, Jörg; Schmidt-Choudhury, Anjona; Rosignoli, Carine; Shpacovitch, Victoria; von Arnim, Ulrike; Metze, Dieter; Rukwied, Roman; Schmelz, Martin; Paus, Ralf; Voegel, Johannes J; Schmidt, Wolfgang E; Steinhoff, Martin

    2010-11-01

    Pituitary adenylate cyclase-activating peptide (PACAP) is an important neuropeptide and immunomodulator in various tissues. Although this peptide and its receptors (ie, VPAC1R, VPAC2R, and PAC1R) are expressed in human skin, their biological roles are unknown. Therefore, we tested whether PACAP regulates vascular responses in human skin in vivo. When injected intravenously, PACAP induced a significant, concentration-dependent vascular response (ie, flush, erythema, edema) and mediated a significant and concentration-dependent increase in intrarectal body temperature that peaked at 2.7°C. Topical application of PACAP induced marked concentration-dependent edema. Immunohistochemistry revealed a close association of PACAP-immunoreactive nerve fibers with mast cells and dermal blood vessels. VPAC1R was expressed by dermal endothelial cells, CD4+ and CD8+ T cells, mast cells, and keratinocytes, whereas VPAC2R was expressed only in keratinocytes. VPAC1R protein and mRNA were also detected in human dermal microvascular endothelial cells. The PACAP-induced change in cAMP production in these cells demonstrated VPAC1R to be functional. PACAP treatment of organ-cultured human skin strongly increased the number of CD31+ vessel cross-sections. Taken together, these results suggest that PACAP directly induces vascular responses that may be associated with neurogenic inflammation, indicating for the first time that PACAP may be a crucial vascular regulator in human skin in vivo. Antagonists to PACAP function may be beneficial for the treatment of inflammatory skin diseases with a neurogenic component.

  5. In vivo quantification of human dermal skin aging using SHG and autofluorescence

    NASA Astrophysics Data System (ADS)

    Puschmann, Stefan; Rahn, Christian-Dennis; Wenck, Horst; Gallinat, Stefan; Fischer, Frank

    2012-03-01

    There are visible changes during skin aging. In the extracellular matrix these changes referred to as intrinsic aging (skin areas not exposed to sunlight) and extrinsic aging can be measured using various methods, such as subjective clinical evaluation, histology and molecular analysis. In this study we developed a new parameter for the non-invasive quantitative determination of dermal skin aging utilizing a five-dimensional intravital tomography (5D-IVT). This device, also known as 5D - multi-photon laser scanning microscopy, is a powerful tool to investigate (photo)aging-associated alterations in vivo. Structural alterations in the dermis of extrinsically aged (chronically sun-exposed) and intrinsically aged (sun-protected) human skin were recorded utilizing the collagen-specific second harmonic generation (SHG) signal and the elastin-specific autofluorescence (AF) signal. Recording took place in young and elderly volunteers. The resulting images were processed in order to gain the elastin percentage and the collagen percentage per image. Then, the elastin - to - collagen ratio (ELCOR) was calculated. With respect to volar forearm skin, the ELCOR significantly increased with age. In elderly volunteers, the ELCOR value calculated for the chronically sun-exposed temple area was significantly augmented compared with the sun-protected upper arm area. Based on 5D-IVT we introduce the ELCOR as a new means to quantify age-associated alterations in the extracellular matrix of in vivo human skin. This novel parameter is compared to the currently used "SHG to AF aging index" of the dermis (SAAID).

  6. Intense picosecond THz pulses alter gene expression in human skin tissue in vivo

    NASA Astrophysics Data System (ADS)

    Titova, Lyubov V.; Ayesheshim, Ayesheshim K.; Golubov, Andrey; Rodriguez-Juarez, Rocio; Kovalchuk, Anna; Hegmann, Frank A.; Kovalchuk, Olga

    2013-02-01

    Pulsed terahertz (THz) imaging has been suggested as a novel high resolution, noninvasive medical diagnostic tool. However, little is known about the influence of pulsed THz radiation on human tissue, i.e., its genotoxicity and effects on cell activity and cell integrity. We have carried out a comprehensive investigation of the biological effects of THz radiation on human skin tissue using a high power THz pulse source and an in vivo full-thickness human skin tissue model. We have observed that exposure to intense THz pulses causes DNA damage and changes in the global gene expression profile in the exposed skin tissue. Several of the affected genes are known to play major roles in human cancer. While the changes in the expression levels of some of them suggest possible oncogenic effects of pulsed THz radiation, changes in the expression of the other cancer-related genes might have a protective influence. This study may serve as a roadmap for future investigations aimed at elucidating the exact roles that all the affected genes play in skin carcinogenesis and in response to pulsed THz radiation.

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

    NASA Astrophysics Data System (ADS)

    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.

  8. High-speed fiber based polarization-sensitive optical coherence tomography of in vivo human skin.

    PubMed

    Saxer, C E; de Boer, J F; Park, B H; Zhao, Y; Chen, Z; Nelson, J S

    2000-09-15

    A high-speed single-mode fiber-based polarization-sensitive optical coherence tomography (PS OCT) system was developed. With a polarization modulator, Stokes parameters of reflected flight for four input polarization states are measured as a function of depth. A phase modulator in the reference arm of a Michelson interferometer permits independent control of the axial scan rate and carrier frequency. In vivo PS OCT images of human skin are presented, showing subsurface structures that are not discernible in conventional OCT images. A phase retardation image in tissue is calculated based on the reflected Stokes parameters of the four input polarization states.

  9. New developments in two-photon analysis of human skin in vivo

    NASA Astrophysics Data System (ADS)

    Riemann, I.; Schwarz, M.; Stracke, F.; Ehlers, A.; Dimitrow, E.; Kaatz, M.; König, K.; Le Harzic, R.

    2009-02-01

    Two-photon imaging of human skin using ultra short laser pulses can be used to obtain information about the state of cells and tissues by means of their natural autofluorescence. Using this method, it is possible to determine whether the normal cell pattern is disturbed or the autofluorescence is influenced by internal or external stimuli. Two-photon fluorescence lifetime imaging (FLIM) can further enhance this providing information about physiological processes, fluorophores (like NAD(P)H, collagen, keratin, elastin, flavins, melanin,...) and external applied probes inside cells and tissue parts. For example the part of the cells metabolism and energy level can be determined by analyzing the NADH regarding its free / bound state and its oxidized / reduced state. The combination of two-photon imaging with FLIM may lead to a better understanding and diagnosis of skin reactions and disorders. We also present some results of in vivo simultaneous collagen and elastin measurements in skin dermis. Changes of dermal collagen and elastin content are characteristic for skin aging as well as for pathological skin conditions.

  10. Multiple spatially resolved reflection spectroscopy for in vivo determination of carotenoids in human skin and blood

    NASA Astrophysics Data System (ADS)

    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.

  11. Retinoids suppress cysteine-rich protein 61 (CCN1), a negative regulator of collagen homeostasis, in skin equivalent cultures and aged human skin in vivo.

    PubMed

    Quan, Taihao; Qin, Zhaoping; Shao, Yuan; Xu, Yiru; Voorhees, John J; Fisher, Gary J

    2011-07-01

    Alterations in connective tissue collagen are prominent features of both chronologically aged and photoaged (ageing because of sun exposure) human skin. These age-related abnormalities are mediated in part by cysteine-rich protein 61 (CCN1). CCN1 is elevated in the dermis of both chronologically aged and photoaged human skin in vivo and promotes aberrant collagen homeostasis by down-regulating type I collagen, the major structural protein in skin, and promoting collagen degradation. Vitamin A and its metabolites have been shown to improve chronologically aged and photoaged skin by promoting deposition of new collagen and preventing its degradation. Here, we investigated regulation of CCN1 expression by retinoids in skin equivalent cultures and chronologically aged and photoaged human skin in vivo. In skin equivalent cultures, all-trans retinoic acid (RA), the major bioactive form of vitamin A in skin, significantly increased type I procollagen and reduced collagenase (matrix metalloproteinases-1, MMP-1). Addition of recombinant human CCN1 to skin equivalent cultures significantly reduced type I procollagen and increased MMP-1. Importantly, RA significantly reduced CCN1 expression in skin equivalent cultures. Topical treatment with retinol (vitamin A, 0.4%) for 7days significantly reduced CCN1 mRNA and protein expression in both chronologically aged (80+years) and photoaged human skin in vivo, compared to vehicle-treated skin. These data indicate that the mechanism by which retinoids improve aged skin, through increased collagen production, involves down-regulation of CCN1.

  12. Evaluation of variations of biomolecular constituents in human skin in vivo by near-infrared Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Huang, Zhiwei; Zeng, Haishan; MacAulay, Calum E.; Hamzavi, Iltefat; McLean, David I.; Lui, Harvey

    2001-10-01

    A portable and rapid near-infrared (NIR) Raman spectroscopy system together with a tissue Raman probe was developed and utilized to acquire in vivo skin Raman spectra at 785 nm excitation. We demonstrated that good quality in vivo skin Raman spectra free of interferences of fiber fluorescence and silica Raman signals can be acquired within 5 seconds. Distinct Raman peaks in the 800-1800 cm-1 range can be discerned clearly from various skin sites of the body. The intensity ratio of the Raman band at 1655 cm-1 to that at 1445 cm-1 was used to evaluate the variation of the protein/lipid depositions in the skin. The results show that the regional variations in the molecular composition and structure can be determined in vivo, suggesting that NIR Raman spectroscopy will be useful to non-invasively measure important biochemical parameters of human skin.

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

    SciTech Connect

    Woo June Choi; Wang, R K

    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)

  14. Assessment of penetration of quantum dots through in vitro and in vivo human skin using the human skin equivalent model and the tape stripping method

    SciTech Connect

    Jeong, Sang Hoon; Kim, Jae Hwan; Yi, Sang Min; Lee, Jung Pyo; Kim, Jin Ho; Sohn, Kyung Hee; Park, Kui Lea; Kim, Meyoung-Kon; Son, Sang Wook

    2010-04-09

    Quantum dots (QDs) are rapidly emerging as an important class of nanoparticles (NPs) with potential applications in medicine. However, little is known about penetration of QDs through human skin. This study investigated skin penetration of QDs in both in vivo and in vitro human skin. Using the tape stripping method, this study demonstrates for the first time that QDs can actually penetrate through the stratum corneum (SC) of human skin. Transmission electron microscope (TEM) and energy diverse X-ray (EDX) analysis showed accumulation of QDs in the SC of a human skin equivalent model (HSEM) after dermal exposure to QDs. These findings suggest possible transdermal absorption of QDs after dermal exposure over a relatively long period of time.

  15. In vivo skin treatment with tissue-tolerable plasma influences skin physiology and antioxidant profile in human stratum corneum.

    PubMed

    Fluhr, Joachim W; Sassning, Sven; Lademann, Olaf; Darvin, Maxim E; Schanzer, Sabine; Kramer, Axel; Richter, Heike; Sterry, Wolfram; Lademann, Juergen

    2012-02-01

    The antimicrobial treatment of wounds is still a major problem. Tissue-tolerable electrical plasma (TTP) is a new approach for topical microbial disinfection of the skin surface. The aim of the present study was to investigate the influence of TTP on a carotenoid profile in relation to skin physiology parameters (epidermal barrier function, stratum corneum (SC) hydration, surface temperature and irritation parameters). We were interested in the interaction of TTP and the antioxidative network, as well as the consequences for skin physiology parameters. These parameters are also indicative of TTP safety in vivo. For plasma application, 'Kinpen 09' was used (surface exposure 30-43°C) for 3 s. Beta-carotene and water profiles were assessed by in vivo Raman microspectroscopy (skin composition analyzer 3510). Skin physiology parameters were measured with Tewameter TM 300, Corneometer CM 825, skin thermometer and Chromameter CR 300. All parameters were assessed non-invasively on seven healthy volunteers before and after plasma application in vivo. We could show that TTP application leads to a decrease in beta-carotene especially in the superficial SC. Skin-surface temperature increased by 1.74°C, while the transepidermal water loss (TEWL) increase indicated an impaired barrier function. SC hydration decreased as seen in water profile especially in the superficial layers and capacitance values. A slight increase in skin redness was measurable. The induction of reactive oxygen species is probably the major contributor of TTP efficacy in skin disinfection. Skin physiology parameters were influenced without damaging the skin or skin functions, indicating the safety of TTP under in vivo conditions.

  16. High-resolution multiphoton tomography of human skin in vivo and in vitro

    NASA Astrophysics Data System (ADS)

    Riemann, Iris; Dimitrov, Enrico; Fischer, Peter; Reif, Annette; Kaatz, Martin; Elsner, Peter; Konig, Karsten

    2004-09-01

    The novel compact femtosecond NIR (near infrared) laser imaging system DermaInspect was used to perform for the first time in vivo high resolution non-invasive 4D tomography of human skin based on multiphoton autofluorescence imaging and second harmonic generation (SHG). Using fast galvoscan mirrors, a time correlated single photon counting (TCSPC) module and femtosecond 80 MHz laser pulses in the spectral range of 750 nm-850 nm human skin was analyzed with subcellular spatial resolution (3D) and 250 ps temporal resolution (4D). The non-linear induced autofluorescence originates from naturally endogenous fluorophores and protein structures like NAD(P)H, flavins, phorphyrins, melanin, elastin and collagen. Collagenous structures were detected using SHG. Tissues of patients with dermatological disorders like nevi and melanoma have been investigated with a clear visualization of cells and intratissue structures. Further characterization of those components was performed by the fluorescence lifetime imaging (FLIM) and the determination of two photon excitation spectra. This method of non invasive high resolution optical biopsy provides a painless diagnostic tool for dermatological applications.

  17. In vivo transformation of human skin with human papillomavirus type 11 from condylomatot acuminata

    SciTech Connect

    Kreider, J.W.; Howett, M.K.; Lill, N.L.; Bartlett, G.L.; Zaino, R.J.; Sedlacek, T.V.; Mortel, R.

    1986-08-01

    Human papillomaviruses (HPVs) have been implicated in the development of a number of human malignancies, but direct tests of their involvement have not been possible. The authors describe a system in which human skin from various skin from various sites was infected with HPV type 11 (HPV-11) extracted from vulvar condylomata and was grafted beneath the renal capsule of athymic mice. Most of the skin grafts so treated underwent morphological transformation, resulting in the development of condylomata identical to those which occur spontaneously in patients. Foreskins responded with the most vigorous proliferative response to HPV-11. The lesions produced the characteristic intranuclear group-specific antigen of papillomaviruses. Both dot blot and Southern blot analysis of DNA from the lesions revealed the presence of HPV-11 DNA in the transformed grafts. These results demonstrate the first laboratory system for the study of the interaction of human skin with an HPV. The method may be useful in understanding the mechanisms of HPV transformation and replication and is free of the ethical restraints which have impeded study. This system will allow the direct study of factors which permit neoplastic progression of HPV-induced cutaneous lesions in human tissues.

  18. In vivo barrier challenge and long-term recovery in human facial skin.

    PubMed

    Gorcea, Mihaela; Hadgraft, Jonathan; Lane, Majella E; Moore, David J

    2013-06-01

    Recently, we developed a biophysical approach to characterize in vivo facial cheek skin as a function of stratum corneum (SC) depth, barrier function and during a 24-h recovery period. The current study extends this work and characterizes the human facial cheek after barrier challenge and, for the first time, facial SC barrier recovery over a 4-week period. Changes in the corneocyte size over the 4-week recovery period, and correlations with changes in Trans-Epidermal Water Loss (TEWL) were monitored. This approach allows complete characterization of SC barrier function after a full biological regeneration of the SC barrier following tape stripping. The structural and compositional changes in facial cheek were investigated using Attenuated Total Reflectance-Fourier Transform Infra Red (ATR-FTIR) spectroscopy, tape stripping, TEWL measurements and image analysis combined with optical microscopy to characterize the SC depth profile during the tape stripping stress and over 4-week recovery period. TEWL increased significantly from baseline after sequential tape stripping. Corneocyte size decreased with successive tape stripping. An inverse direct correlation was determined between TEWL and corneocyte surface area. After 4 weeks, the corneocyte size and TEWL for the facial cheek recovered 100% from the tape stripping procedure. The in vivo ATR-FTIR data demonstrated that lipid and sebum components on the surface of the facial cheek SC recovered within 24 h post tape stripping, whereas protein (Amide II) and water components recovered after 1 week.

  19. Removing noises caused by motion artefacts in microcirculation maps of human skin in vivo.

    PubMed

    Chen, C; Shi, W; Gao, W

    2015-12-01

    This paper presents a zero-padding and cross-correlation technique-based correlation mapping optical coherence tomography (ZPCC-cmOCT) to reconstruct microcirculation maps of human skin in vivo, which can remove the background decorrelation noise caused by motion artefacts. In conventional correlation mapping optical coherence tomography method, the correlation degree of static tissue may be lowered by the motion artefacts due to cardiac and respiratory motion, resulting in background decorrelation noise in microcirculation maps. In zero-padding and cross-correlation technique-based correlation mapping optical coherence tomography method, structural images are first obtained by performing Fourier transform on zero-padded interference fringes, and then cross-correlation-based image registration is utilized to align local areas in two adjacent structural images. Finally, correlation mapping optical coherence tomography method is performed to generate microcirculation maps. Both phantom experiments and in vivo experiments were implemented and the results demonstrate that the proposed method is capable of providing microcirculation maps with the background decorrelation noise removed.

  20. In vivo stepwise multi-photon activation fluorescence imaging of melanin in human skin

    NASA Astrophysics Data System (ADS)

    Lai, Zhenhua; Gu, Zetong; Abbas, Saleh; Lowe, Jared; Sierra, Heidy; Rajadhyaksha, Milind; DiMarzio, Charles

    2014-03-01

    The stepwise multi-photon activated fluorescence (SMPAF) of melanin is a low cost and reliable method of detecting melanin because the activation and excitation can be a continuous-wave (CW) mode near infrared (NIR) laser. Our previous work has demonstrated the melanin SMPAF images in sepia melanin, mouse hair, and mouse skin. In this study, we show the feasibility of using SMPAF to detect melanin in vivo. in vivo melanin SMPAF images of normal skin and benign nevus are demonstrated. SMPAF images add specificity for melanin detection than MPFM images and CRM images. Melanin SMPAF is a promising technology to enable early detection of melanoma for dermatologists.

  1. In-vitro and in-vivo study of dye diffusion into the human skin and hair follicles

    NASA Astrophysics Data System (ADS)

    Genina, Elina A.; Bashkatov, Alexey N.; Sinichkin, Yurii P.; Kochubey, Vyacheslav I.; Lakodina, Nina A.; Perpelitzina, Olga A.; Altshuler, Gregory B.; Tuchin, Valery V.

    2000-11-01

    We present experimental results on in vitro and in vivo investigation of dye diffusion into the human skin and hair follicles. It was shown that dyeing as a method of enhancement of the absorption coefficient of hair follicle tissue components can be used for selective photodestruction of hair follicle and surrounding tissues. Strength and depth of hair follicle dyeing inside the skin were determined for various dyes.

  2. Applying tattoo dye as a third-harmonic generation contrast agent for in vivo optical virtual biopsy of human skin

    NASA Astrophysics Data System (ADS)

    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.

  3. Remote in vivo imaging of human skin corneocytes by means of an optical fiber bundle

    NASA Astrophysics Data System (ADS)

    Dromard, Tanguy; Ravaine, Valérie; Ravaine, Serge; Lévêque, Jean-Luc; Sojic, Neso

    2007-05-01

    Human corneocytes forming the outermost layer of the epidermis (stratum corneum) were imaged in vivo by epifluorescence through a coherent optical fiber bundle. A very simple and rapid method to remotely visualize the cells forming this protective layer of the skin is presented. After the topical application of fluorescein, the distal face of an optical fiber bundle is gently applied perpendicularly onto the labeled skin (contact mode). Remote fluorescence images of the corneocytes are acquired in 50ms through the bundle comprising 30 000 individually cladded 3.5μm diameter optical fibers. The very short focal distance which is an intrinsic characteristic of such bundles, allows visualizing only the most superficial monolayer of cells in contact with the external environment. An image displays about 400-500 cells directly on the human body. The size and the arrangement of the corneocytes can thus be acquired and analyzed in a very simple and easy way. The method is flexible and can be used for any location on the human body. Using a gradient-index lens objective (magnification 2.8×) fused to the distal face of the bundle allows the shape of the corneocytes to be better resolved. In addition, the working distance is 300μm and hence this second approach works in a noncontact imaging mode. Both approaches are complementary and allow providing instantaneously either a global view of the cells with a possible statistical determination of their area or morphological information, which are essential for dermatology and cosmetic sciences. Finally, to improve the quality and the contrast of the recorded images, we tested silica nanoparticles containing fluorescein. In brief, this diagnostic method is nontoxic, painless, easy to use, noninvasive, and nondestructive.

  4. In Vivo Assessment of Acute UVB Responses in Normal and Xeroderma Pigmentosum (XP-C) Skin-Humanized Mouse Models

    PubMed Central

    García, Marta; Llames, Sara; García, Eva; Meana, Alvaro; Cuadrado, Natividad; Recasens, Mar; Puig, Susana; Nagore, Eduardo; Illera, Nuria; Jorcano, José Luis; Del Rio, Marcela; Larcher, Fernando

    2010-01-01

    In vivo studies of UVB effects on human skin are precluded by ethical and technical arguments on volunteers and inconceivable in cancer-prone patients such as those affected with Xeroderma Pigmentosum (XP). Establishing reliable models to address mechanistic and therapeutic matters thus remains a challenge. Here we have used the skin-humanized mouse system that circumvents most current model constraints. We assessed the UVB radiation effects including the sequential changes after acute exposure with respect to timing, dosage, and the relationship between dose and degree-sort of epidermal alteration. On Caucasian-derived regenerated skins, UVB irradiation (800 J/m2) induced DNA damage (cyclobutane pyrimidine dimers) and p53 expression in exposed keratinocytes. Epidermal disorganization was observed at higher doses. In contrast, in African descent–derived regenerated skins, physiological hyperpigmentation prevented tissue alterations and DNA photolesions. The acute UVB effects seen in Caucasian-derived engrafted skins were also blocked by a physical sunscreen, demonstrating the suitability of the system for photoprotection studies. We also report the establishment of a photosensitive model through the transplantation of XP-C patient cells as part of a bioengineered skin. The inability of XP-C engrafted skin to remove DNA damaged cells was confirmed in vivo. Both the normal and XP-C versions of the skin-humanized mice proved proficient models to assess UVB-mediated DNA repair responses and provide a strong platform to test novel therapeutic strategies. PMID:20558577

  5. A simple skin blister technique for the study of in vivo transmigration of human leukocytes.

    PubMed

    Davidsson, Lisa; Björkman, Lena; Christenson, Karin; Alsterholm, Mikael; Movitz, Charlotta; Thorén, Fredrik B; Karlsson, Anna; Welin, Amanda; Bylund, Johan

    2013-07-31

    The study of human leukocytes is almost exclusively conducted using cells isolated from peripheral blood. This is especially true for neutrophils, despite the fact that these cells are of main (pathological) importance in extravascular tissues upon e.g., infection and/or tissue damage. The journey from circulation to tissue is typically associated with a number of cellular changes, making the cells primed, or hyper-responsive, and in many aspects distinct from the cells present in circulation. Models to obtain in vivo transmigrated leukocytes from human tissue are available, but not widely used. We describe here an easy-to-use model for the study of local inflammation, stemming from limited tissue damage, which can be used to isolate viable and functional leukocytes. The model is based on the generation of aseptic skin blisters, formed by the application of negative pressure, and allows for investigations of the cellular infiltrate as well as of soluble mediators present in the exudate. We believe that this method, combined with modern analysis equipment suitable for small volumes and cell numbers, could be of great use for increasing our understanding of the nature and function of leukocytes that have left circulation and transmigrated to inflamed tissues.

  6. 3D bioprinting of functional human skin: production and in vivo analysis.

    PubMed

    Cubo, Nieves; Garcia, Marta; Del Cañizo, Juan F; Velasco, Diego; Jorcano, Jose L

    2016-12-05

    Significant progress has been made over the past 25 years in the development of in vitro-engineered substitutes that mimic human skin, either to be used as grafts for the replacement of lost skin, or for the establishment of in vitro human skin models. In this sense, laboratory-grown skin substitutes containing dermal and epidermal components offer a promising approach to skin engineering. In particular, a human plasma-based bilayered skin generated by our group, has been applied successfully to treat burns as well as traumatic and surgical wounds in a large number of patients in Spain. There are some aspects requiring improvements in the production process of this skin; for example, the relatively long time (three weeks) needed to produce the surface required to cover an extensive burn or a large wound, and the necessity to automatize and standardize a process currently performed manually. 3D bioprinting has emerged as a flexible tool in regenerative medicine and it provides a platform to address these challenges. In the present study, we have used this technique to print a human bilayered skin using bioinks containing human plasma as well as primary human fibroblasts and keratinocytes that were obtained from skin biopsies. We were able to generate 100 cm(2), a standard P100 tissue culture plate, of printed skin in less than 35 min (including the 30 min required for fibrin gelation). We have analysed the structure and function of the printed skin using histological and immunohistochemical methods, both in 3D in vitro cultures and after long-term transplantation to immunodeficient mice. In both cases, the generated skin was very similar to human skin and, furthermore, it was indistinguishable from bilayered dermo-epidermal equivalents, handmade in our laboratories. These results demonstrate that 3D bioprinting is a suitable technology to generate bioengineered skin for therapeutical and industrial applications in an automatized manner.

  7. In Vivo Imaging of Human and Mouse Skin with a Handheld Dual-Axis Confocal Fluorescence Microscope

    PubMed Central

    Gonzalez-Gonzalez, Emilio; Mandella, Michael J.; Kino, Gordon S.; Solgaard, Olav; Leake, Devin; Kaspar, Roger L.; Oro, Anthony; Contag, Christopher H.

    2013-01-01

    Advancing molecular therapies for the treatment of skin diseases will require the development of new tools that can reveal spatiotemporal changes in the microanatomy of the skin and associate these changes with the presence of the therapeutic agent. For this purpose, we evaluated a handheld dual-axis confocal (DAC) microscope that is capable of in vivo fluorescence imaging of skin, using both mouse models and human skin. Individual keratinocytes in the epidermis were observed in three-dimensional image stacks after topical administration of near-infrared (NIR) dyes as contrast agents. This suggested that the DAC microscope may have utility in assessing the clinical effects of a small interfering RNA (siRNA)-based therapeutic (TD101) that targets the causative mutation in pachyonychia congenita (PC) patients. The data indicated that (1) formulated indocyanine green (ICG) readily penetrated hyperkeratotic PC skin and normal callused regions compared with nonaffected areas, and (2) TD101-treated PC skin revealed changes in tissue morphology, consistent with reversion to nonaffected skin compared with vehicle-treated skin. In addition, siRNA was conjugated to NIR dye and shown to penetrate through the stratum corneum barrier when topically applied to mouse skin. These results suggest that in vivo confocal microscopy may provide an informative clinical end point to evaluate the efficacy of experimental molecular therapeutics. PMID:21191407

  8. Weight-bearing-induced changes in the microtopography and structural stiffness of human skin in vivo following immobility periods.

    PubMed

    Dobos, Gabor; Gefen, Amit; Blume-Peytavi, Ulrike; Kottner, Jan

    2015-01-01

    Pressure ulcers (PUs) are injuries to the skin and underlying tissues, caused by sustained deformations and occur frequently in aged patients. Skin microtopography and stiffness affect the interaction of skin with contact surfaces contributing to PU development. We simulated immobility in 20 healthy females (mean age 69.9 years). Skin microtopography and stiffness were measured at the PU predilection sites before and after loading. Skin roughness decreased at the heels by 18.1% after 90 minutes (p = 0.022), but remained unchanged at the sacrum and the upper back. Structural elasticity and elastic deformations increased at all skin areas; changes over time were significant at the sacrum (p = 0.005) and the heel, (p = 0.002). The residual skin deformation increased at all skin areas after loading significantly at the sacrum (32.0%, p = 0.013) and upper back (20.6%, p = 0.007). The structural "biological" elasticity of the skin decreased significantly at the upper back after loading, but remained unchanged at the heels. All skin changes recovered after unloading. Results indicate that prolonged loading causes structural skin changes in humans in vivo in PU predilection sites. The pathogenesis of PUs is different at the heels, the sacral and upper back skin.

  9. In vivo imaging of microvascular changes in inflammatory human skin induced by tape stripping and mosquito saliva using optical microangiography

    NASA Astrophysics Data System (ADS)

    Baran, Utku; Choi, Woo J.; Wang, Ruikang K.

    2015-03-01

    Tape stripping on human skin induces mechanical disruptions of the epidermal barrier that lead to minor skin inflammation which leads to temporary changes in microvasculature. On the other hand, when mosquitoes probe the skin for blood feeding, they inject saliva in dermal tissue. Mosquito saliva is known to exert various biological activities, such as dermal mast cell degranulation, leading to fluid extravasation and neutrophil influx. This inflammatory response remain longer than the tape stripping caused inflammation. In this study, we demonstrate the capabilities of swept-source optical coherence tomography (OCT) in detecting in vivo microvascular response of inflammatory human skin. Optical microangiography (OMAG), noninvasive volumetric microvasculature in vivo imaging method, has been used to track the vascular responses after tape stripping and mosquito bite. Vessel density has been quantified and used to correlate with the degree of skin irritation. The proved capability of OMAG technique in visualizing the microvasculature network under inflamed skin condition can play an important role in clinical trials of treatment and diagnosis of inflammatory skin disorders as well as studying mosquito bite's perception by the immune system and its role in parasite transmission.

  10. Analysis of the in vivo confocal Raman spectral variability in human skin

    NASA Astrophysics Data System (ADS)

    Mogilevych, Borys; dos Santos, Laurita; Rangel, Joao L.; Grancianinov, Karen J. S.; Sousa, Mariane P.; Martin, Airton A.

    2015-06-01

    Biochemical composition of the skin changes in each layer and, therefore, the skin spectral profile vary with the depth. In this work, in vivo Confocal Raman spectroscopy studies were performed at different skin regions and depth profile (from the surface down to 10 μm) of the stratum corneum, to verify the variability and reproducibility of the intra- and interindividual Raman data. The Raman spectra were collected from seven healthy female study participants using a confocal Raman system from Rivers Diagnostic, with 785 nm excitation line and a CCD detector. Measurements were performed in the volar forearm region, at three different points at different depth, with the step of 2 μm. For each depth point, three spectra were acquired. Data analysis included the descriptive statistics (mean, standard deviation and residual) and Pearson's correlation coefficient calculation. Our results show that inter-individual variability is higher than intraindividual variability, and variability inside the SC is higher than on the skin surface. In all these cases we obtained r values, higher than 0.94, which correspond to high correlation between Raman spectra. It reinforces the possibility of the data reproducibility and direct comparison of in vivo results obtained with different study participants of the same age group and phototype.

  11. Ethosomes for skin delivery of ammonium glycyrrhizinate: in vitro percutaneous permeation through human skin and in vivo anti-inflammatory activity on human volunteers.

    PubMed

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

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

    SciTech Connect

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

    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)

  14. In vivo visualization of microneedle conduits in human skin using laser scanning microscopy

    NASA Astrophysics Data System (ADS)

    Bal, S.; Kruithof, A. C.; Liebl, H.; Tomerius, M.; Bouwstra, J.; Lademann, J.; Meinke, M.

    2010-03-01

    Solid microneedles enhance the penetration of drugs into the viable skin but little is known about the geometry of the conduits in vivo. Therefore, laser scanning microscopy was used to visualize the conduits of a microneedle system with needles at a length of 300 μm in 6 healthy subjects over a period of time. The model drug, a fluorescent dye was applied before and after piercing. Laser scanning microscopy was evaluated as being an excellent method to monitor the geometry and closure of the conduits over time. The used microneedle system was evaluated as suitable to enhance the transport of model drugs into the viable epidermis without bleeding and a short closure time of the conduits at the skin surface.

  15. Confocal Raman spectroscopy: In vivo biochemical changes in the human skin by topical formulations under UV radiation.

    PubMed

    Tosato, M G; Orallo, D E; Ali, S M; Churio, M S; Martin, A A; Dicelio, L

    2015-12-01

    A new approach to the study of the effects on human skin of mycosporine-like amino acids (MAAs) and gadusol (Gad) incorporated in polymer gel is proposed in this work. The depth profile and photoprotector effects of Pluronic F127® gels containing each of the natural actives were evaluated by in vivo confocal Raman spectroscopy aiming at the analysis of the biochemical changes on human skin. Hierarchical cluster analysis (HCA) showed that the data corresponding to different depths of the skin, from surface to 4 μm, and from 6 to 16 μm, remained in the same cluster. In vivo Raman spectra, classified into five different layers of epidermis according to their similarities, indicated that the amount of Gad gel increased by about 26% in the outermost layer of the stratum corneum (SC) and that MAAs gel at 2 μm depth was 103.4% higher than in the outermost layer of the SC. Variations in the SC of urocanic acid at 1490-1515 cm(-1) and 1652 cm(-1) and histidine at 1318 cm(-1) were calculated, before and after UV exposure with or without gels. With the application of gels the vibrational modes that correspond to lipids in trans conformation (1063 and 1128 cm(-1)) increased with respect to normal skin, whereas gauche conformation (1085 cm(-1)) disappeared. Our studies suggest that gels protected the skin against the stress of the natural defense mechanism caused by high levels of UV exposure.

  16. In vivo laser scanning microscopic investigation of the decontamination of hazardous substances from the human skin

    NASA Astrophysics Data System (ADS)

    Lademann, J.; Patzelt, A.; Schanzer, S.; Richter, H.; Gross, I.; Menting, K. H.; Frazier, L.; Sterry, W.; Antoniou, C.

    2010-12-01

    The stimulation of the penetration of topically applied substances into the skin is a topic of intensive dermatological and pharmacological research. In this context, it was found that in addition to the intercellular penetration, the follicular penetration also represents an efficient penetration pathway. The hair follicles act as a long-term reservoir for topically applied substances. They are surrounded by all important target structures, such as blood capillaries, stem and dendritic cells. Therefore, the hair follicles, as well as the skin, need to be protected from hazardous substances. The traditional method of decontamination after respective accidental contacts consists of an intensive washing of the skin. However, during this mechanical procedure, the substances can be pushed even deeper into the hair follicles. In the present study, absorbent materials were applied to remove a fluorescent model substance from the skin without inducing mechanical stress. The results were compared to the decontamination effects obtained by intensive washing. Investigations were performed by means of in vivo laser scanning microscopy (LSM). The comparison revealed that decontamination with absorbent materials is more effective than decontamination with washing processes.

  17. Fluorescence dynamics of human epidermis (ex vivo) and skin (in vivo)

    NASA Astrophysics Data System (ADS)

    Salomatina, Elena V.; Pravdin, Alexander B.

    2003-10-01

    The temporal behavior of autofluorescence of human skin and epidermis under continuous UV-irradiation has been studied. Fluorescence spectra and kinetic curves of fluorescence intensity have been obtained. The fluorescence intensity recovery after dark period also has been examined. The vitiligo skin and epidermis were used for comparing their spectra with reflectance and fluorescence spectra of healthy skin. The epidermal samples were prepared using surface epidermis stripping technique. It has been concluded that fluorophores being undergone the UVA photobleaching are actually present in epidermal layer, and immediate pigment darkening does contribute, no less than a half of magnitude, to the autofluorescence decrease under continuous UVA irradiation.

  18. In vivo confirmation of hydration-induced changes in human-skin thickness, roughness and interaction with the environment.

    PubMed

    Dąbrowska, Agnieszka K; Adlhart, Christian; Spano, Fabrizio; Rotaru, Gelu-Marius; Derler, Siegfried; Zhai, Lina; Spencer, Nicholas D; Rossi, René M

    2016-09-15

    The skin properties, structure, and performance can be influenced by many internal and external factors, such as age, gender, lifestyle, skin diseases, and a hydration level that can vary in relation to the environment. The aim of this work was to demonstrate the multifaceted influence of water on human skin through a combination of in vivo confocal Raman spectroscopy and images of volar-forearm skin captured with the laser scanning confocal microscopy. By means of this pilot study, the authors have both qualitatively and quantitatively studied the influence of changing the depth-dependent hydration level of the stratum corneum (SC) on the real contact area, surface roughness, and the dimensions of the primary lines and presented a new method for characterizing the contact area for different states of the skin. The hydration level of the skin and the thickness of the SC increased significantly due to uptake of moisture derived from liquid water or, to a much lesser extent, from humidity present in the environment. Hydrated skin was smoother and exhibited higher real contact area values. The highest rates of water uptake were observed for the upper few micrometers of skin and for short exposure times.

  19. Hazards and benefits of in-vivo Raman spectroscopy of human skin

    NASA Astrophysics Data System (ADS)

    Carter, Elizabeth A.; Williams, Adrian C.; Barry, Brian W.; Edwards, Howell G.

    1999-04-01

    The resurgence of Raman spectroscopy, in the late 1980's has led to an increase in the use of the technique for the analysis of biological tissues. Consequently, Raman spectroscopy is now regarded to be a well-established non- invasive, non-destructive technique, which is used to obtain good quality spectra from biological tissues with minimal fluorescence. What is presently of interest to our group is to develop further and establish the technique for in vivo investigations of healthy and diseased skin. This presentation discusses some potentially valuable clinical applications of the technique, and also highlights some of the experimental difficulties that were encountered when examining patients who were receiving treatment for psoriasis.

  20. [Cultivated human hair follicle cells are capable of integrating to skin structure in vivo].

    PubMed

    Cheremnykh, E S; Radiukhina, N V; Rutkevich, P N; Shevelev, A Ia; Vlasik, T N; Voroteliak, E A; Vasil'ev, A V; Terskikh, V V

    2010-01-01

    In the present study, human keratinocytes and dermal papilla cells were labeled to investigate their behaviour after intradermal transplantation. Cells were transduced by lentiviral vectors that bore marker gene encoding green fluorescent protein (copGFP) or red fluorescent protein (DsRed). A portion of transgene expressing cells was evaluated by flow cytometry. Genetic constructions that we used provided high level (> 95 %) of transduction of hair follicle cells. In vitro transduced cells were injected under the epidermis of human skin fragments, and these fragments were then transplanted under the skin of immunodeficient mice. Injected epidermal keratinocytes were found, mainly, in hair follicles and partially in a zone of interfollicular epidermis, while dermal papilla cells were found in papilla derma. The results of the present research show that the chosen genetic constructions obtained on a basis of human immunodeficiency lentivirs are capable of effective and stable transduction of human skin cells. Injected cells survived and were found in the corresponding structures of the skin.

  1. In vivo evaluation of Fe in human skin employing X-Ray Fluorescence Methodology (XRF)

    SciTech Connect

    Estevam, M.; Appoloni, C. R.

    2007-02-12

    Recent technological improvements allow the method of in vivo XRF to provide useful sensibility for diagnostics or monitoring in biomedical applications. In cases of hereditary sanguine disorders as the {beta}-thalassaemia or a genetic disorder like Haemochromatosis, there is a high concentration of elements as Fe, Zn and Cu in the skin and internal organs, due to the treatment of those abnormalities or due to the own dysfunction caused by the disease. The levels of Fe related to the patient bearers of the {beta}-thalassaemia are determined, at the moment, measuring a protein in the sanguine current, called ferritin. The monitoring of the protein is ineffective in several situations, such as when the patient suffers any disturbance of health. Nowadays, the main forms of measuring the levels of those metals through hepatic storage are the biopsy of the liver, that is invasive and potentially dangerous, presenting a rate of mortality of 0.1%, and by means of magnetic susceptibilities that employs a quantum superconductor, which is highly expensive and there are only three main world centers with this equipment This work investigates the use of a Si PIN-diode detector and a 238Pu source (13 and 17keV; 13%; 95.2mCi; 86y) for the measurement of Fe skin levels compatible with those associated to the disease {beta}-thalassaemia. XRF spectra were analyzed using a set of AXIL-WinQXAS programs elaborated and disseminated by the IAEA. The determination coefficient of the calibration model (sensitivity curve) was 0.97. Measurements on skin phantoms containing concentrations of Fe in the range from 10 to 150 parts per million (ppm), indicate that we are able to detect Fe at levels of the order of 15ppm, using monitoring periods of 50 seconds and skin entrance dose less than 10 mSv, The literature reports skin Fe levels from 15.0 to 60.0 ppm in normal persons and from 70 to 150 ppm in thalassaemics patients. So, the employed methodology allows the measurement of the skin Fe

  2. In vivo evaluation of Fe in human skin employing X-Ray Fluorescence Methodology (XRF)

    NASA Astrophysics Data System (ADS)

    Estevam, M.; Appoloni, C. R.

    2007-02-01

    Recent technological improvements allow the method of in vivo XRF to provide useful sensibility for diagnostics or monitoring in biomedical applications. In cases of hereditary sanguine disorders as the β-thalassaemia or a genetic disorder like Haemochromatosis, there is a high concentration of elements as Fe, Zn and Cu in the skin and internal organs, due to the treatment of those abnormalities or due to the own dysfunction caused by the disease. The levels of Fe related to the patient bearers of the β-thalassaemia are determined, at the moment, measuring a protein in the sanguine current, called ferritin. The monitoring of the protein is ineffective in several situations, such as when the patient suffers any disturbance of health. Nowadays, the main forms of measuring the levels of those metals through hepatic storage are the biopsy of the liver, that is invasive and potentially dangerous, presenting a rate of mortality of 0.1%, and by means of magnetic susceptibilities that employs a quantum superconductor, which is highly expensive and there are only three main world centers with this equipment This work investigates the use of a Si PIN-diode detector and a 238Pu source (13 and 17keV; 13%; 95.2mCi; 86y) for the measurement of Fe skin levels compatible with those associated to the disease β-thalassaemia. XRF spectra were analyzed using a set of AXIL-WinQXAS programs elaborated and disseminated by the IAEA. The determination coefficient of the calibration model (sensitivity curve) was 0.97. Measurements on skin phantoms containing concentrations of Fe in the range from 10 to 150 parts per million (ppm), indicate that we are able to detect Fe at levels of the order of 15ppm, using monitoring periods of 50 seconds and skin entrance dose less than 10 mSv, The literature reports skin Fe levels from 15.0 to 60.0 ppm in normal persons and from 70 to 150 ppm in thalassaemics patients. So, the employed methodology allows the measurement of the skin Fe concentration.

  3. Design and commissioning of a directly coupled in-vivo multiphoton microscope for skin imaging in humans and large animals

    NASA Astrophysics Data System (ADS)

    Mulholland, William J.; Kendall, Mark A.

    2004-02-01

    The application of near infrared multiphoton excitation to the laser-scanning microscope was first conceived by Denk, Strickler and Webb in 1990. Since then, advances in design have seen the multiphoton laser scanning microscope (MPLSM) applied to a wide range of biological research areas, including skin imaging and vaccine delivery. The technique has the attributes of low phototoxicity, high-resolution functional imaging to depths in scattered tissues. These characteristics have encouraged engineers and scientists to develop in-vivo imaging systems. For these applications, laser excitation pulses can be delivered to the sample through optical fibers. Although this solution provides a number of advantages relating to movement and flexibility of the site of interest relative to the laser source, the peak powers that can be delivered down the fiber are limited. We report on the design and commissioning of a directly coupled in-vivo MPM system, optimised for the imaging of epidermal vaccines delivered to a range of biological models and humans. Specifically, we seek to apply the system to visualise in-vivo, the influence of hand-held, helium powered needle-free systems on skin cells. A standard Nikon E600FN microscope, dissected above the optical plane was cantilevered from a vibration isolated table using rigid support arms. The modified microscope was coupled to an infrared optimised Bio-Rad Radiance 2100MP, multiphoton dedicated laser scanning control and image acquisition system. Femtosecond laser pulses were provided by a 10W Verdi pumped Mira Ti:Sapphire laser, from Coherent Inc. The microscope was modified such that the transmission half may be selectively attached for conventional imaging with ex-vivo and cell culture samples, or removed for in-vivo imaging of skin sites on the body of humans and large animals. Optical performance of the system, and aspects of its design and commissioning are discussed in this paper.

  4. Thermal Transport Characteristics of Human Skin Measured In Vivo Using Ultrathin Conformal Arrays of Thermal Sensors and Actuators

    PubMed Central

    Webb, R. Chad; Pielak, Rafal M.; Bastien, Philippe; Ayers, Joshua; Niittynen, Juha; Kurniawan, Jonas; Manco, Megan; Lin, Athena; Cho, Nam Heon; Malyrchuk, Viktor; Balooch, Guive; Rogers, John A.

    2015-01-01

    Measurements of the thermal transport properties of the skin can reveal changes in physical and chemical states of relevance to dermatological health, skin structure and activity, thermoregulation and other aspects of human physiology. Existing methods for in vivo evaluations demand complex systems for laser heating and infrared thermography, or they require rigid, invasive probes; neither can apply to arbitrary regions of the body, offers modes for rapid spatial mapping, or enables continuous monitoring outside of laboratory settings. Here we describe human clinical studies using mechanically soft arrays of thermal actuators and sensors that laminate onto the skin to provide rapid, quantitative in vivo determination of both the thermal conductivity and thermal diffusivity, in a completely non-invasive manner. Comprehensive analysis of measurements on six different body locations of each of twenty-five human subjects reveal systematic variations and directional anisotropies in the characteristics, with correlations to the thicknesses of the epidermis (EP) and stratum corneum (SC) determined by optical coherence tomography, and to the water content assessed by electrical impedance based measurements. Multivariate statistical analysis establishes four distinct locations across the body that exhibit different physical properties: heel, cheek, palm, and wrist/volar forearm/dorsal forearm. The data also demonstrate that thermal transport correlates negatively with SC and EP thickness and positively with water content, with a strength of correlation that varies from region to region, e.g., stronger in the palmar than in the follicular regions. PMID:25658947

  5. Thermal transport characteristics of human skin measured in vivo using ultrathin conformal arrays of thermal sensors and actuators.

    PubMed

    Webb, R Chad; Pielak, Rafal M; Bastien, Philippe; Ayers, Joshua; Niittynen, Juha; Kurniawan, Jonas; Manco, Megan; Lin, Athena; Cho, Nam Heon; Malyrchuk, Viktor; Balooch, Guive; Rogers, John A

    2015-01-01

    Measurements of the thermal transport properties of the skin can reveal changes in physical and chemical states of relevance to dermatological health, skin structure and activity, thermoregulation and other aspects of human physiology. Existing methods for in vivo evaluations demand complex systems for laser heating and infrared thermography, or they require rigid, invasive probes; neither can apply to arbitrary regions of the body, offers modes for rapid spatial mapping, or enables continuous monitoring outside of laboratory settings. Here we describe human clinical studies using mechanically soft arrays of thermal actuators and sensors that laminate onto the skin to provide rapid, quantitative in vivo determination of both the thermal conductivity and thermal diffusivity, in a completely non-invasive manner. Comprehensive analysis of measurements on six different body locations of each of twenty-five human subjects reveal systematic variations and directional anisotropies in the characteristics, with correlations to the thicknesses of the epidermis (EP) and stratum corneum (SC) determined by optical coherence tomography, and to the water content assessed by electrical impedance based measurements. Multivariate statistical analysis establishes four distinct locations across the body that exhibit different physical properties: heel, cheek, palm, and wrist/volar forearm/dorsal forearm. The data also demonstrate that thermal transport correlates negatively with SC and EP thickness and positively with water content, with a strength of correlation that varies from region to region, e.g., stronger in the palmar than in the follicular regions.

  6. In vivo low-coherence spectroscopic measurements of local hemoglobin absorption spectra in human skin

    NASA Astrophysics Data System (ADS)

    Bosschaart, Nienke; Faber, Dirk J.; van Leeuwen, Ton G.; Aalders, Maurice C. G.

    2011-10-01

    Localized spectroscopic measurements of optical properties are invaluable for diagnostic applications that involve layered tissue structures, but conventional spectroscopic techniques lack exact control over the size and depth of the probed tissue volume. We show that low-coherence spectroscopy (LCS) overcomes these limitations by measuring local attenuation and absorption coefficient spectra in layered phantoms. In addition, we demonstrate the first in vivo LCS measurements of the human epidermis and dermis only. From the measured absorption in two distinct regions of the dermal microcirculation, we determine total hemoglobin concentration (3.0+/-0.5 g/l and 7.8+/-1.2 g/l) and oxygen saturation.

  7. In vivo low-coherence spectroscopic measurements of local hemoglobin absorption spectra in human skin.

    PubMed

    Bosschaart, Nienke; Faber, Dirk J; van Leeuwen, Ton G; Aalders, Maurice C G

    2011-10-01

    Localized spectroscopic measurements of optical properties are invaluable for diagnostic applications that involve layered tissue structures, but conventional spectroscopic techniques lack exact control over the size and depth of the probed tissue volume. We show that low-coherence spectroscopy (LCS) overcomes these limitations by measuring local attenuation and absorption coefficient spectra in layered phantoms. In addition, we demonstrate the first in vivo LCS measurements of the human epidermis and dermis only. From the measured absorption in two distinct regions of the dermal microcirculation, we determine total hemoglobin concentration (3.0±0.5 g∕l and 7.8±1.2 g∕l) and oxygen saturation.

  8. High-speed fiber-based polarization-sensitive optical coherence tomography of in vivo human skin

    SciTech Connect

    Saxer, Christopher E.; Boer, Johannes F. de; Park, B. Hyle; Zhao, Yonghua; Chen, Zhongping; Nelson, J. Stuart

    2000-09-15

    A high-speed single-mode fiber-based polarization-sensitive optical coherence tomography (PS OCT) system was developed. With a polarization modulator, Stokes parameters of reflected flight for four input polarization states are measured as a function of depth. A phase modulator in the reference arm of a Michelson interferometer permits independent control of the axial scan rate and carrier frequency. In vivo PS OCT images of human skin are presented, showing subsurface structures that are not discernible in conventional OCT images. A phase retardation image in tissue is calculated based on the reflected Stokes parameters of the four input polarization states. (c) 2000 Optical Society of America.

  9. In vivo confocal microscopy of human skin: a new design for cosmetology and dermatology.

    PubMed

    Corcuff, P; Gonnord, G; Piérard, G E; Lévéque, J L

    1996-08-01

    In-depth exploration of cellular structures in living human skin in situ is possible with the tandem scanning microscope (TSM). However, the rigid design of the microscope limited observations to the arms, hands, and fingers. A mobile version allowing the investigation of any parts of the body has been designed. The head containing the Nipkow disk and the optical path were the only part saved from the original TSM. This prototype can be used to observe, in real time, the different skin structures down to a depth of 200 microns and to measure the thickness of the different layers with micron precision level. The hydration of the stratum corneum (SC) could be assessed. For example, lengthy immersion of the hand in water led to an increase in SC thickness without affecting that of the living epidermis. Occlusive patch tests also showed that water and, even more so. propylene glycol, led to transient swelling of the SC. In dermatology, the example of psoriasis illustrated the value of the TSM for describing, measuring, and assessing pathologic skin changes. The availability of this noninvasive method for observing changes with time in a given skin site should prove useful for monitoring treatment efficacy. This tool opens up new insight for the investigation of cutaneous pathophysiology.

  10. Wideband optical elastography of in vivo human skin using geometrically focused surface waves

    NASA Astrophysics Data System (ADS)

    Kearney, Steven P.; Dai, Zoujun; Royston, Thomas J.

    2014-02-01

    Viscoelastic models are fit to shear moduli derived from geometrically focused surface waves (GFS) on human skin using viscoelastic wave theory. Unlike in previous studies on the analytical solution and experimental measurement of radially outward traveling surface waves, measurable radially inward traveling GFS waves can be generated over a wider range of frequencies as attenuation is countered by the converging nature of the wavefront. This enables a more accurate and broader assessment of both the shear storage and loss moduli of the material, which are expected to vary with frequency. In the present study, GFS waves are applied to human skin on the posterior side of the forearm using a scanning LASER Doppler vibrometer. Surface wave measurements can then be used to estimate the complex frequency dependent viscoelastic properties of biological tissue, which are affected by numerous pathologies. Using a phantom gel this technique was validated through comparison with other studies. It was found that spring-pot and fractional Voigt models yield a potentially stable model parameter for skin, but more study is needed to confirm. [Work supported by NIH: Grant # EB012142.

  11. In vivo reflectance-mode confocal microscopy assessments: impact of overweight on human skin microcirculation and histomorphology

    NASA Astrophysics Data System (ADS)

    Altintas, Ahmet A.; Aust, Matthias C.; Krämer, Robert; Vogt, Peter M.; Altintas, Mehmet A.

    2016-03-01

    Reflectance-mode confocal microscopy (RCM) enables in vivo assessment of the human skin. Impact of overweight on both human skin microcirculation and histomorphology has not been investigated in vivo. The purpose of this study is to evaluate both microcirculation and histomorphology in vivo in overweight. In 10 normotensive overweight nondiabetic individuals (OW-group, BMI 29.1±2.7 kg/m2) and 10 age- and sex-matched healthy lean controls (CO-group, BMI 20.4±1.9 kg/m2) the following parameters were evaluated using RCM: dermal blood cell flow (DBCF), density of dermal capillaries (DDC), epidermal thickness (ET), and epidermal cell size (ECS). DBCF was counted at 63.11±4.14 cells/min in OW-group and at 51.06±3.84 cells/min in CO-group (P<0.05). DDC was reduced in OW-group (4.91±0.39 capillaries/mm2) compared to the controls (6.02±0.64 capillaries/mm2, P<0.05). Histometric evaluation of ET reveals thickening in OW-group compared to the CO-group (54.79±4.25 μm versus 44.03±3.11 μm, P<0.05). ECS differed significantly (P<0.05) in OW-group (821.3±42.02 μm2) compared to the controls (772.6±34.79 μm2). Inverse correlation of dermal capillary density and overweight point to reduced total tissue perfusion while positive related blood cell flow reveals vasodilatation. Increase of both ET and cell size indicates remodeling of cutaneous histomorphology, maybe as an early stage of adiposity-related skin condition.

  12. Motion correction of in vivo three-dimensional optical coherence tomography of human skin using a fiducial marker

    PubMed Central

    Liew, Yih Miin; McLaughlin, Robert A.; Wood, Fiona M.; Sampson, David D.

    2012-01-01

    This paper presents a novel method based on a fiducial marker for correction of motion artifacts in 3D, in vivo, optical coherence tomography (OCT) scans of human skin and skin scars. The efficacy of this method was compared against a standard cross-correlation intensity-based registration method. With a fiducial marker adhered to the skin, OCT scans were acquired using two imaging protocols: direct imaging from air into tissue; and imaging through ultrasound gel into tissue, which minimized the refractive index mismatch at the tissue surface. The registration methods were assessed with data from both imaging protocols and showed reduced distortion of skin features due to motion. The fiducial-based method was found to be more accurate and robust, with an average RMS error below 20 µm and success rate above 90%. In contrast, the intensity-based method had an average RMS error ranging from 36 to 45 µm, and a success rate from 50% to 86%. The intensity-based algorithm was found to be particularly confounded by corrugations in the skin. By contrast, tissue features did not affect the fiducial-based method, as the motion correction was based on delineation of the flat fiducial marker. The average computation time for the fiducial-based algorithm was approximately 21 times less than for the intensity-based algorithm. PMID:22876343

  13. Influence of microneedle shape on the transport of a fluorescent dye into human skin in vivo.

    PubMed

    Bal, Suzanne M; Kruithof, Annelieke C; Zwier, Raphaël; Dietz, Ekkehart; Bouwstra, Joke A; Lademann, Jürgen; Meinke, Martina C

    2010-10-15

    Microneedles can enhance the penetration of vaccines into the skin for transcutaneous vaccination. In this study for the first time the influence of microneedle geometry on the transport through the formed conduits was visualised in human volunteers by confocal laser scanning microscopy. Three differently shaped 300 μm long microneedle arrays were selected and fluorescein was applied either before or after piercing. Based on the intensity a distinction was made between regions with high and low intensity fluorescence (HIF and LIF). The areas of both intensities were quantified over time. In most cases HIF areas were only present in the stratum corneum, while LIF areas were also present in the viable epidermis. The areas were larger if fluorescein was applied after piercing compared to before piercing. After 15 min almost no HIF was present anymore at the skin surface. The microneedle geometry, but not the manner of application affected the shape and depth of the conduits. In conclusion we showed that the different microneedle arrays are able to form conduits in the skin, but the geometry of the microneedles influences the penetration of the fluorescent dye. This is the first step towards a more rational design of microneedle arrays for transcutaneous vaccination.

  14. A broad-spectrum sunscreen prevents UVA radiation-induced gene expression in reconstructed skin in vitro and in human skin in vivo.

    PubMed

    Marionnet, Claire; Grether-Beck, Susanne; Seité, Sophie; Marini, Alessandra; Jaenicke, Thomas; Lejeune, François; Bastien, Philippe; Rougier, André; Bernerd, Françoise; Krutmann, Jean

    2011-06-01

    The efficacy of sunscreens to protect against ultraviolet (UV) A radiation is usually assessed by measuring erythema formation and pigmentation. The biological relevance of these endpoints for UVA-induced skin damage, however, is not known. We therefore carried out two complementary studies to determine UVA protection provided by a broad-spectrum sunscreen product at a molecular level by studying UVA radiation-induced gene expression. One study was performed on human reconstructed skin in vitro with a semi-global gene expression analysis of 227 genes in fibroblasts and 244 in keratinocytes. The second one was conducted in vivo in human volunteers and focused on genes involved in oxidative stress response and photo-ageing (haeme oxygenase-1, superoxide dismutase-2, glutathione peroxidase, catalase, matrix metalloproteinase-1). In-vitro UVA radiation induced modulation of genes involved in extracellular matrix homeostasis, oxidative stress, heat shock responses, cell growth, inflammation and epidermal differentiation. Sunscreen pre-application abrogated or significantly reduced these effects, as underlined by unsupervised clustering analysis. The in vivo study confirmed that the sunscreen prevented UVA radiation-induced transcriptional expression of the five studied genes. These findings indicate the high efficacy of a broad-spectrum sunscreen in protecting human skin against UVA-induced gene responses and suggest that this approach is a biologically relevant complement to existing methods.

  15. Doppler standard deviation imaging for clinical monitoring of in vivo human skin blood flow

    SciTech Connect

    Zhao, Yonghua; Chen, Zhongping; Saxer, Christopher; Shen, Qimin; Xiang, Shaohua; Boer, Johannes F. de; Nelson, J. Stuart

    2000-09-15

    We used a novel phase-resolved optical Doppler tomographic (ODT) technique with very high flow-velocity sensitivity (10 {mu}m/s) and high spatial resolution (10 {mu}m) to image blood flow in port-wine stain (PWS) birthmarks in human skin. In addition to the regular ODT velocity and structural images, we use the variance of blood flow velocity to map the PWS vessels. Our device combines ODT and therapeutic systems such that PWS blood flow can be monitored in situ before and after laser treatment. To the authors' knowledge this is the first clinical application of ODT to provide a fast semiquantitative evaluation of the efficacy of PWS laser therapy in situ and in real time. (c) 2000 Optical Society of America.

  16. Evaluation of carotenoids and reactive oxygen species in human skin after UV irradiation: a critical comparison between in vivo and ex vivo investigations.

    PubMed

    Meinke, Martina C; Müller, Robert; Bechtel, Anne; Haag, Stefan F; Darvin, Maxim E; Lohan, Silke B; Ismaeel, Fakher; Lademann, Jürgen

    2015-03-01

    UV irradiation is one of the most harmful exogenous factors for the human skin. In addition to the development of erythema, free radicals, that is reactive oxygen species (ROS), are induced under its influence and promote the development of oxidative stress in the skin. Several techniques are available for determining the effect of UV irradiation. Resonance Raman spectroscopy (RRS) measures the reduction of the carotenoid concentration, while electron paramagnetic resonance (EPR) spectroscopy enables the analysis of the production of free radicals. Depending on the method, the skin parameters are analysed in vivo or ex vivo. This study provides a critical comparison between in vivo and ex vivo investigations on the ROS formation and carotenoid depletion caused by UV irradiation in human skin. The oxygen content of tissue was also determined. It was shown that the antioxidant status measured in the skin samples in vivo and ex vivo was different. The depletion in the carotenoid concentration in vivo exceeded the value determined ex vivo by a factor of about 1.5, and the radical formation after UV irradiation was significantly greater in vivo by a factor of 3.5 than that measured in excised human skin, which can be explained by the lack of oxygen ex vivo.

  17. An innovative application of a small-scale motion analysis technique to quantify human skin deformation in vivo.

    PubMed

    Mahmud, Jamaluddin; Holt, Cathy A; Evans, Sam L

    2010-03-22

    This study highlights a new experimental method developed to measure full-field deformation of human skin in vivo. The technique uses a small-scale Qualisys (Sweden) 3D motion capture system and an array of reflective markers placed on the forearm of five healthy volunteers. A load of up to 1.5N was applied to induce skin deformation by pulling a fine wire attached to the centre of the marker configuration. Loading and marker displacements were recorded simultaneously. 3D marker trajectory data was generated for three different load directions. Tests were repeated to investigate accuracy and repeatability. Calibration results indicate the accuracy of the motion capture system with an average residual of 0.05 mm. The procedure was found to be repeatable and accurate for five repeated tests of measured displacements with a maximum variance of 5%. Experimental data are presented to demonstrate robustness and the ability to produce significant outputs. For all five subjects, at 1N load, the mean and standard deviations of skin axial and lateral displacements were found to be 11.7+/-1.6mm and 12.3+/-3.3mm, respectively. The axial displacements ratio (u(90)/u(0)) ranges from 0.63 to 1.45 with mean+/-standard deviation of 0.982+/-0.34 and 0.982+/-0.32 for left and right arms, respectively. The experiments generated useful and accurate data that can be used to study the viscoelastic, hyperelastic or anisotropic behaviour of human skin. The measured displacements will be analysed further to determine the mechanical properties of skin using inverse Finite Element Analysis and Ogden model.

  18. In vitro and in vivo assessment of the effect of Laurus novocanariensis oil and essential oil in human skin.

    PubMed

    Viciolle, E; Castilho, P; Rosado, C

    2012-12-01

    Laurus novocanariensis is an endemic plant from the Madeira Island forest that derives a fatty oil, with a strong spicy odour, from its berries that has been used for centuries in traditional medicine to treat skin ailments. This work aimed to investigate the effect of the application of both the oil and its essential oil on normal skin, to assess their safety and potential benefits. Diffusion studies with Franz cells using human epidermal membranes were conducted. The steady-state fluxes of two model molecules through untreated skin were compared with those obtained after a 2-h pre-treatment with either the oil or the essential oil. Additionally, eleven volunteers participated in the in vivo study that was conducted on the forearm and involved daily application of the oil for 5 days. Measurements were performed every day in the treated site with bioengineering methods that measure erythema, irritation and loss of barrier function. Slightly higher steady-state fluxes were observed for both the lipophilic and the hydrophilic molecule when the epidermal membranes were pre-treated. Nevertheless, such differences had no statistical significance, which seems to confirm that neither the oil nor the essential oil impaired the epidermal barrier. Results collected with the Chromameter, the Laser Doppler Flowmeter and the visual scoring are in agreement with those established in the in vitro study. They indicate that the repeated application of the oil did not cause erythema, because the results observed in the first day of the study were maintained throughout the week. Application of the oil did not affect the skin barrier function, because the transepidermal water loss remained constant throughout the study. The stratum corneum hydration was slightly reduced on days 4 and 5. This work shows that both the oil and the essential oil were well tolerated by the skin and did not cause significant barrier impairment or irritation.

  19. Multiphoton excitation microscopy of in vivo human skin. Functional and morphological optical biopsy based on three-dimensional imaging, lifetime measurements and fluorescence spectroscopy.

    PubMed

    Masters, B R; So, P T; Gratton, E

    1998-02-09

    Two-photon excitation microscopy has the potential as an effective, noninvasive, diagnostic tool for in vivo examination of human deep tissue structure at the subcellular level. By using infrared photons as the excitation source in two-photon microscopy, a significant improvement in penetration depth can be achieved because of the much lower tissue scattering and absorption coefficients in the infrared wavelengths. Two-photon absorption occurs primarily at the focal point and provides the physical basis for optical sectioning. Multiphoton excitation microscopy at 730 nm was used to image in vivo human skin autofluorescence from the surface to a depth of about 200 microns. The spectroscopic data suggest that reduced pyridine nucleotides, NAD(P)H, are the primary source of the skin autofluorescence using 730 nm excitation. This study demonstrates the use of multiphoton excitation microscopy for functional imaging of the metabolic states of in vivo human skin cells and provides a functional and morphological optical biopsy.

  20. Molecular events underlying maggot extract promoted rat in vivo and human in vitro skin wound healing.

    PubMed

    Li, Pei-Nan; Li, Hong; Zhong, Li-Xia; Sun, Yuan; Yu, Li-Jun; Wu, Mo-Li; Zhang, Lin-Lin; Kong, Qing-You; Wang, Shou-Yu; Lv, De-Cheng

    2015-01-01

    Maggot extracts promote wound healing, but their bioactive part(s) and molecular effects on the regenerating tissues/cells remain largely unclear. These issues are addressed here by treating rat skin wounds, human keratinocyte line/HaCat and fibroblasts with maggot secretion/excretion, and the extracts of maggots without and with secretion/excretion. The wound closure rates, cell proliferation activities, and statuses of wound healing-related signaling pathways (STAT3, Notch1, Wnt2, NF-κB, and TGF-beta/Smad3) and their downstream gene expression (c-Myc, cyclin D1, and VEGF) are evaluated by multiple approaches. The results reveal that the maggot extracts, especially the one from the maggots without secretion/excretion, show the best wound healing-promoting effects in terms of quicker wound closure rates and more rapid growth of keratinocytes and fibroblasts. Of the five signaling pathways checked, the ones mediated by TGF-beta/Smad3, and STAT3 are activated in the untreated wounds and become further enhanced by the maggot extracts, accompanied with c-Myc, VEGF, and cyclin D1 up-regulation. Our results thus show (1) that both body extract and secretion/excretion of maggots contain favorable wound healing elements and (2) that the enhancement of TGF-beta/Smad3 and STAT3 signaling activities may be the main molecular effects of maggot extracts on the wound tissues.

  1. An unsupervised machine learning method for delineating stratum corneum in reflectance confocal microscopy stacks of human skin in vivo

    NASA Astrophysics Data System (ADS)

    Bozkurt, Alican; Kose, Kivanc; Fox, Christi A.; Dy, Jennifer; Brooks, Dana H.; Rajadhyaksha, Milind

    2016-02-01

    Study of the stratum corneum (SC) in human skin is important for research in barrier structure and function, drug delivery, and water permeability of skin. The optical sectioning and high resolution of reflectance confocal microscopy (RCM) allows visual examination of SC non-invasively. Here, we present an unsupervised segmentation algorithm that can automatically delineate thickness of the SC in RCM images of human skin in-vivo. We mimic clinicians visual process by applying complex wavelet transform over non-overlapping local regions of size 16 x 16 μm called tiles, and analyze the textural changes in between consecutive tiles in axial (depth) direction. We use dual-tree complex wavelet transform to represent textural structures in each tile. This transform is almost shift-invariant, and directionally selective, which makes it highly efficient in texture representation. Using DT-CWT, we decompose each tile into 6 directional sub-bands with orientations in +/-15, 45, and 75 degrees and a low-pass band, which is the decimated version of the input. We apply 3 scales of decomposition by recursively transforming the low-pass bands and obtain 18 bands of different directionality at different scales. We then calculate mean and variance of each band resulting in a feature vector of 36 entries. Feature vectors obtained for each stack of tiles in axial direction are then clustered using spectral clustering in order to detect the textural changes in depth direction. Testing on a set of 15 RCM stacks produced a mean error of 5.45+/-1.32 μm, compared to the "ground truth" segmentation provided by a clinical expert reader.

  2. Previous chronic exogenous glucocorticoid administration in vivo does not affect functional characteristics and cellular lifespan of human skin fibroblasts in vitro.

    PubMed

    Pratsinis, Harris; Dimozi, Anastasia; Pilichos, Konstantinos; Tsagarakis, Stylianos; Yiacoumettis, Andreas M; Kletsas, Dimitris

    2011-06-01

    Excess of glucocorticoids (GCs) has been reported to lead to skin atrophy and impaired wound healing. The present study investigates whether human skin fibroblasts suffer permanent damages due to a long-term exposure to GC excess. Fibroblasts obtained from patients being under GC treatment for periods over one year were cultured under standard conditions in vitro, and studied regarding pivotal parameters involved in skin homeostasis and aging, i.e. collagen production, cell proliferation, and cellular replicative lifespan. No statistical differences were observed regarding these functions compared to those of normal human skin fibroblasts. Furthermore, no differences between normal and patient-derived cells were observed regarding their sensitivity to a supra-physiological cortisol concentration. In conclusion, the prolonged exposure of human skin fibroblasts in vivo to high concentrations of exogenously-administered GC does not lead to persistent adverse effects on their physiology.

  3. Percutaneous absorption of PCBs from soil: In vivo rhesus monkey, in vitro human skin, and binding to powdered human stratum corneum

    SciTech Connect

    Wester, R.C.; Maibach, H.I.; Sedik, L.; Melendres, J.; Wade, M. )

    1993-07-01

    Polychlorinated biphenyls (PCBs) are ubiquitous and persistent environmental pollutants. The major resident site for these PCBs is the soil, and human skin is frequently in contact with soil. Our objective was to determine the percutaneous absorption of the PCBs Aroclor 1242 and Aroclor 1254 from soil. PCB-contaminated soil was prepared at levels of 44 ppm Aroclor 1242 and 23 ppm Aroclor 1254. PCB concentrations on skin were 1.75 micrograms/cm2 for Aroclor 1242 and 0.91 microgram/cm2 for Aroclor 1254. In vivo percutaneous absorption in the rhesus monkey was determined by urinary and fecal [14C]-PCB excretion for a 5-wk period following topical dosing. Absorption of Aroclor 1242 was determined in vitro with human skin for comparative purposes. In vivo in the rhesus monkey the percutaneous absorption of Aroclor 1242 was 13.8 +/- 2.7 (SD)% of the dose and the absorption of Aroclor 1254 was 14.1 +/- 1.0%. These absorption amounts are similar to the absorption of Aroclor 1242 and 1254 from other vehicles (mineral oil, trichlorobenzene, acetone). With in vitro percutaneous absorption through human skin, most of the Aroclor 1242 and Aroclor 1254 resided in the skin and the amounts were dependent upon dosing vehicle (water > mineral oil > soil). Both PCBs readily partitioned from water into soil and human powdered stratum corneum. By difference the partitioning favored both PCBs going from soil into stratum corneum. These data emphasize the role of soil in percutaneous absorption and provide information for appropriate risk assessment.

  4. In vivo analysis of tissue by Raman microprobe: examination of human skin lesions and esophagus Barrett's mucosa on an animal model

    NASA Astrophysics Data System (ADS)

    Tfayli, Ali; Piot, Olivier; Derancourt, Sylvie; Cadiot, Guillaume; Diebold, Marie D.; Bernard, Philippe; Manfait, Michel

    2006-02-01

    In the last few years, Raman spectroscopy has been increasingly used for the characterization of normal and pathological tissues. A new Raman system, constituted of optic fibers bundle coupled to an axial Raman spectrometer (Horiba Jobin Yvon SAS), was developed for in vivo investigations. Here, we present in vivo analysis on two tissues: human skin and esophagus mucosa on a rat model. The skin is a directly accessible organ, representing a high diversity of lesions and cancers. Including malignant melanoma, basal cell carcinoma and the squamous cell carcinoma, skin cancer is the cancer with the highest incidence worldwide. Several Raman investigations were performed to discriminate and classify different types of skin lesions, on thin sections of biopsies. Here, we try to characterize in vivo the different types of skin cancers in order to be able to detect them in their early stages of development and to define precisely the exeresis limits. Barrett's mucosa was also studied by in vivo examination of rat's esophagus. Barrett's mucosa, induced by gastro-esophageal reflux, is a pretumoral state that has to be carefully monitored due to its high risk of evolution in adenocarcinoma. A better knowledge of the histological transformation of esophagus epithelium in a Barrett's type will lead to a more efficient detection of the pathology for its early diagnosis. To study these changes, an animal model (rats developing Barrett's mucosa after duodenum - esophagus anastomosis) was used. Potential of vibrational spectroscopy for Barrett's mucosa identification is assessed on this model.

  5. Intravital multiphoton tomography as a novel tool for non-invasive in vivo analysis of human skin affected with atopic dermatitis

    NASA Astrophysics Data System (ADS)

    Huck, Volker; Gorzelanny, Christian; Thomas, Kai; Niemeyer, Verena; Luger, Thomas A.; König, Karsten; Schneider, Stefan W.

    2010-02-01

    Atopic Dermatitis (AD) is an inflammatory disease of human skin. Its pathogenesis is still unknown; however, dysfunctions of the epidermal barrier and the immune response are regarded as key factors for the development of AD. In our study we applied intravital multiphoton tomography (5D-IVT), equipped with a spectral-FLIM module for in-vivo and ex-vivo analysis of human skin affected with AD. In addition to the morphologic skin analysis, FLIM technology gain access to the metabolic status of the epidermal cells referring to the NADH specific fluorescence lifetime. We evaluated a characteristic 5D-IVT skin pattern of AD in comparison to histological sections and detected a correlation with the disease activity measured by SCORAD. FLIM analysis revealed a shift of the mean fluorescence lifetime (taum) of NADH, indicating an altered metabolic activity. Within an ex-vivo approach we have investigated cryo-sections of human skin with or without barrier defects. Spectral-FLIM allows the detection of autofluorescent signals that reflect the pathophysiological conditions of the defect skin barrier. In our study the taum value was shown to be different between healthy and affected skin. Application of the 5D-IVT allows non-invasive in-vivo imaging of human skin with a penetration depth of 150 μm. We could show that affected skin could be distinguished from healthy skin by morphological criteria, by FLIM and by spectral-FLIM. Further studies will evaluate the application of the 5D-IVT technology as a diagnostic tool and to monitor the therapeutic efficacy.

  6. Effectiveness of hand-cleansing formulations containing tea tree oil assessed ex vivo on human skin and in vivo with volunteers using European standard EN 1499.

    PubMed

    Messager, S; Hammer, K A; Carson, C F; Riley, T V

    2005-03-01

    The efficacy of formulations containing tea tree oil (TTO) has been assessed in vitro in previous studies. Products that passed the European suspension test guidelines were investigated further in this study, in vivo with volunteers using the European handwashing method (EN 1499) and ex vivo using freshly excised human skin samples. The activity of 5% TTO in 0.001% Tween 80, in a hygienic skin wash (HSW) and in an alcoholic hygienic skin wash (AHSW) was investigated and compared with that of a non-medicated soft soap (SS, control). These formulations were assessed against Escherichia coli K12 as recommended by the European standard. In-vivo results showed that 5% TTO in Tween 80 and the AHSW were significantly more active than the SS after 1 min of handwashing. When assessed ex vivo, these two products were also significantly more active than the reference soap after 1 min of rubbing. Both methods showed that 5% TTO in Tween 80 was generally, although not always, more active than a handwash formulation, and that the AHSW was generally more active than the HSW, although this difference was not significant. The formulations tested, as well as the SS, were more active when assessed in vivo than ex-vivo against E. coli, although only the SS and the HSW were significantly more active in vivo. There appeared to be a pattern in the comparison between ex vivo and in vivo results. The antiseptics tested were, on average, 1.28+/-0.06 times more active when assessed in-vivo than when assessed ex vivo. Nevertheless, the main outcome of the European handwashing method is for the formulation tested to be significantly more active than the SS; both 5% TTO in Tween 80 and the AHSW achieved this both in-vivo and ex-vivo. TTO in Tween 80 and in formulations met the European in-vivo method requirements.

  7. Measurement of complex permittivities of biological materials and human skin in vivo in the frequency band

    SciTech Connect

    Ghodgaonkar, D.K.

    1987-01-01

    A new method, namely, modified infinite sample method, has been developed which is particularly suitable for millimeter-wave dielectric measurements of biological materials. In this method, an impedance transformer is used which reduces the reflectivity of the biological sample. Because of the effect of introducing impendance transformer, the measured reflection coefficients are more sensitive to the complex permittivities of biological samples. For accurate measurement of reflection coefficients, two automated measurment systems were developed which cover the frequencies range of 26.5-60 GHz. An uncertainty analysis was performed to get an estimate of the errors in the measured complex permittivities. The dielectric properties were measured for 10% saline solution, whole human blood, 200 mg/ml bovine serum albumin (BSA) solution and suspension of Saccharomyces cerevisiae cells. The Maxwell-Fricke equation, which is derived from dielectric mixture theory, was used for determination bound water in BSA solution. The results of all biological samples were interpreted by fitting Debye relaxation and Cole-Cole model. It is observed that the dielectric data for the biological materials can be explained on the basis of Debye relaxation of water molecule.

  8. In-vivo Measurement of Complex Relative Permittivity for Human Skin Tissues Using Open-Ended Coaxial Probe

    NASA Astrophysics Data System (ADS)

    Sato, Yusuke; Hirata, Akimasa; Fujiwara, Osamu

    We made in-vivo measurement of the complex relative permittivity of palm and sole in the frequency range from 100 MHz to 40 GHz with a network analyzer and an open-ended coaxial probe, which was compared with Gabriel in-vitro data for skin tissue to reveal that the in-vivo measurement results are mostly lower than the in-vitro data. For validation, we measured the dielectric constant of Teflon sheet with respect to its thickness from 0.05 mm to 5.00 mm, which showed that the open-ended coaxial probe provides sufficient measurement accuracy for Teflon with a thickness of over 0.5 mm, however, the probe data can be affected by the material beneath the Teflon with a thickness of less than 0.5 mm. This means that the in-vivo palm data derive from the epidermis and the dermis including blood, while the in-vivo sole data come from the epidermis. For further investigation, under the assumption that in-vitro data derive from a mixture of epidermis and blood, we calculated the complex relative permittivity for the compound from the Litchtenecker's law of exponent to show a possibility that due to the inclusion of blood, in-vitro measurement may provide a higher relative permittivity than in-vivo measurement.

  9. Combined multi-modal photoacoustic tomography, optical coherence tomography (OCT) and OCT angiography system with an articulated probe for in vivo human skin structure and vasculature imaging

    PubMed Central

    Liu, Mengyang; Chen, Zhe; Zabihian, Behrooz; Sinz, Christoph; Zhang, Edward; Beard, Paul C.; Ginner, Laurin; Hoover, Erich; Minneman, Micheal P.; Leitgeb, Rainer A.; Kittler, Harald; Drexler, Wolfgang

    2016-01-01

    Cutaneous blood flow accounts for approximately 5% of cardiac output in human and plays a key role in a number of a physiological and pathological processes. We show for the first time a multi-modal photoacoustic tomography (PAT), optical coherence tomography (OCT) and OCT angiography system with an articulated probe to extract human cutaneous vasculature in vivo in various skin regions. OCT angiography supplements the microvasculature which PAT alone is unable to provide. Co-registered volumes for vessel network is further embedded in the morphologic image provided by OCT. This multi-modal system is therefore demonstrated as a valuable tool for comprehensive non-invasive human skin vasculature and morphology imaging in vivo. PMID:27699106

  10. Non-invasive in-vivo Raman spectroscopic measurement of the dynamics of the antioxidant substance lycopene in the human skin after a dietary supplementation

    NASA Astrophysics Data System (ADS)

    Darvin, M. E.; Gersonde, I.; Albrecht, H.; Sterry, W.; Lademann, J.

    2007-05-01

    A non-invasive optical method based on resonance Raman spectroscopy was used for the in vivo detection of the concentration of the carotenoid antioxidant substance lycopene in the human skin. The physiological variation of the level of lycopene in the skin during a 6 month period was measured daily in 7 volunteers. It was shown that all volunteers had a different individual level of lycopene in the skin, depending on the lifestyle of volunteers. It was shown that the supplementation of the foodstuffs containing lycopene, such as tomato products and some fruits, increases the level of lycopene in the skin. The increase in the lycopene level can be usually observed on the next day after the supplementation. The present results demonstrate that a diet rich in products containing a high amount of carotenoids, such as lycopene, can be an efficient strategy to increase the carotenoid level of the skin.

  11. Application of the critical angle method to refractive index measurement of human skin in vivo under partial contact.

    PubMed

    Yoshida, Kenichiro; Ohkubo, Kohji; Ojima, Nobutoshi; Iwata, Kayoko

    2013-03-01

    We adapted the critical angle method for measuring rough surfaces under partial contact to acquire an in vivo skin refractive index (RI). Assuming that the total reflection is the simple sum of reflection from areas that are in contact and reflection from those that are not in contact, the RI can be estimated even for partial contact with a rough surface. We found that cheek skin is sufficiently soft that a sufficiently large area can be in contact and that the critical angle was detectable. The RIs of the cheeks of adult females were measured. The RI range was about 1.51 to 1.53, at a wavelength of 550 nm, without considering systematic errors. The RIs of cheeks are significantly correlated with their conductance, which corresponds to their water content. We determined the relationship between the RI and conductance within the variation of skin under normal conditions; this relationship was theoretically obtained in previous studies. In the present study, a direct in vivo measurement method was developed that enabled us to measure the RI in daily life, although this method contains errors for several reasons, including disregarding absorption.

  12. In vivo confocal Raman microspectroscopy of the human skin: highlighting of spectral markers associated to aging via a research of correlation between Raman and biometric mechanical measurements.

    PubMed

    Eklouh-Molinier, Christophe; Gaydou, Vincent; Froigneux, Emmanuel; Barlier, Pascale; Couturaud, Virginie; Manfait, Michel; Piot, Olivier

    2015-11-01

    Skin plays a protective role against the loss of water and external aggression, including mechanical stresses. These crucial functions are ensured by different cutaneous layers, particularly the stratum corneum (SC). During aging, the human skin reveals some apparent modifications of functionalities such as a loss of elasticity. Our investigations aimed at demonstrating that Raman microspectroscopy, as a label-free technique with a high molecular specificity, is efficient to assess in vivo the molecular composition of the skin and the alterations underwent during aging. Our approach was based on a search for correlation between Raman data collected on healthy female volunteers of different ages (from 21 to 70 years old) by means of a remote confocal Raman and skin firmness measurements used as a reference method. Raman and biometric data were then submitted to a partial least square (PLS)-based data processing. Our experiments demonstrated the potential of Raman microspectroscopy to provide an objective in vivo assessment of the skin "biological age" that can be very different from the "chronological age" of the person. In addition, Raman features sensitive to the elasticity and the fatigability of the SC were highlighted. Thereafter, calibration transfer functions were constructed to show the possibility to compare the results obtained during two distinct measurement campaigns conducted with two Raman probes of the same conception. This approach could lead to several interesting prospects, in particular by objectifying the effects of dermocosmetic products on the superficial layers of the skin and by accessing some underlying molecular mechanisms.

  13. Far-infrared in vivo signature of human skin by terahertz time-domain spectroscopy using waveform rebuilding technology

    NASA Astrophysics Data System (ADS)

    Li, Xiangjun; Liu, Jianjun; Hong, Zhi

    2010-11-01

    We present terahertz time-domain spectroscopy characterization of human thumb skin in reflection measurement mode with waveform rebuilding technology. The thumb skin contacts one side of a high resistive silicon wafer with 3 mm thick, and here is an orthogonal incidence of the THz pulse putting on the other side of the wafer. We rebuild the time domain signal from silicon-skin interface as a sample signal by the signal from the air-silicon interface as a reference and a Fresnel transform function between them. Material parameters were calculated by minimizing the difference between the measured sample waveform and a rebuilt one in time domain. The double Debye model parameters for the thumb skin were fitted. The method has potential to research complex layer-structures in skin if a precise model is built.

  14. Measurements of the thermal coefficient of optical attenuation at different depth regions of in vivo human skins using optical coherence tomography: a pilot study.

    PubMed

    Su, Ya; Yao, X Steve; Li, Zhihong; Meng, Zhuo; Liu, Tiegen; Wang, Longzhi

    2015-02-01

    We present detailed measurement results of optical attenuation's thermal coefficients (referenced to the temperature of the skin surface) in different depth regions of in vivo human forearm skins using optical coherence tomography (OCT). We first design a temperature control module with an integrated optical probe to precisely control the surface temperature of a section of human skin. We propose a method of using the correlation map to identify regions in the skin having strong correlations with the surface temperature of the skin and find that the attenuation coefficient in these regions closely follows the variation of the surface temperature without any hysteresis. We observe a negative thermal coefficient of attenuation in the epidermis. While in dermis, the slope signs of the thermal coefficient of attenuation are different at different depth regions for a particular subject, however, the depth regions with a positive (or negative) slope are different in different subjects. We further find that the magnitude of the thermal coefficient of attenuation coefficient is greater in epidermis than in dermis. We believe the knowledge of such thermal properties of skins is important for several noninvasive diagnostic applications, such as OCT glucose monitoring, and the method demonstrated in this paper is effective in studying the optical and biological properties in different regions of skin.

  15. Performance of full-pupil line-scanning reflectance confocal microscopy in human skin and oral mucosa in vivo

    PubMed Central

    Larson, Bjorg; Abeytunge, Sanjeewa; Rajadhyaksha, Milind

    2011-01-01

    Point-scanning reflectance confocal microscopes continue to be successfully translated for detection of skin cancer. Line-scanning, with the use of a single scanner and a linear-array detector, offers a potentially smaller, simpler and lower cost alternative approach, to accelerate widespread dissemination into the clinic. However, translation will require an understanding of imaging performance deep within scattering and aberrating human tissues. We report the results of an investigation of the performance of a full-pupil line-scanning reflectance confocal microscope in human skin and oral mucosa, in terms of resolution, optical sectioning, contrast, signal-to-noise ratio, imaging and the effect of speckle noise. PMID:21750780

  16. Recovery of Aging-Related Size Increase of Skin Epithelial Cells: In vivo Mouse and In vitro Human Study

    PubMed Central

    Sokolov, Igor; Guz, Natali V.; Iyer, Swaminathan; Hewitt, Amy; Sokolov, Nina A.; Erlichman, Joseph S.; Woodworth, Craig D.

    2015-01-01

    The size increase of skin epithelial cells during aging is well-known. Here we demonstrate that treatment of aging cells with cytochalasin B substantially decreases cell size. This decrease was demonstrated on a mouse model and on human skin cells in vitro. Six nude mice were treated by topical application of cytochalasin B on skin of the dorsal left midsection for 140 days (the right side served as control for placebo treatment). An average decrease in cell size of 56±16% resulted. A reduction of cell size was also observed on primary human skin epithelial cells of different in vitro age (passages from 1 to 8). A cell strain obtained from a pool of 6 human subjects was treated with cytochalasin B in vitro for 12 hours. We observed a decrease in cell size that became statistically significant and reached 20–40% for cells of older passage (6–8 passages) whereas no substantial change was observed for younger cells. These results may be important for understanding the aging processes, and for cosmetic treatment of aging skin. PMID:25807526

  17. Responsive corneosurfametry following in vivo skin preconditioning.

    PubMed

    Uhoda, E; Goffin, V; Pierard, G E

    2003-12-01

    Skin is subjected to many environmental threats, some of which altering the structure and function of the stratum corneum. Among them, surfactants are recognized factors that may influence irritant contact dermatitis. The present study was conducted to compare the variations in skin capacitance and corneosurfametry (CSM) reactivity before and after skin exposure to repeated subclinical injuries by 2 hand dishwashing liquids. A forearm immersion test was performed on 30 healthy volunteers. 2 daily soak sessions were performed for 5 days. At inclusion and the day following the last soak session, skin capacitance was measured and cyanoacrylate skin-surface strippings were harvested. The latter specimens were used for the ex vivo microwave CSM. Both types of assessments clearly differentiated the 2 hand dishwashing liquids. The forearm immersion test allowed the discriminant sensitivity of CSM to increase. Intact skin capacitance did not predict CSM data. By contrast, a significant correlation was found between the post-test conductance and the corresponding CSM data. In conclusion, a forearm immersion test under realistic conditions can discriminate the irritation potential between surfactant-based products by measuring skin conductance and performing CSM. In vivo skin preconditioning by surfactants increases CSM sensitivity to the same surfactants.

  18. Intravital multiphoton tomography as an appropriate tool for non-invasive in vivo analysis of human skin affected with atopic dermatitis

    NASA Astrophysics Data System (ADS)

    Huck, Volker; Gorzelanny, Christian; Thomas, Kai; Mess, Christian; Dimitrova, Valentina; Schwarz, Martin; Riemann, Iris; Niemeyer, Verena; Luger, Thomas A.; König, Karsten; Schneider, Stefan W.

    2011-03-01

    Increasing incidence of inflammatory skin diseases such as Atopic Dermatitis (AD) has been noted in the past years. According to recent estimations around 15% of newborn subjects are affected with a disease severity that requires medical treatment. Although its pathogenesis is multifactorial, recent reports indicate that an impaired physical skin barrier predispose for the development of AD. The major part of this barrier is formed by the stratum corneum (SC) wherein corneocytes are embedded in a complex matrix of proteins and lipids. Its components were synthesized in the stratum granulosum (SG) and secreted via lamellar bodies at the SC/SG interface. Within a clinical in vivo study we focused on the skin metabolism at the SC/SG interface in AD affected patients in comparison to healthy subjects. Measurement of fluorescence life-time of NADH provides access to the metabolic state of skin. Due to the application of a 5D intravital tomographic skin analysis we facilitate the non-invasive investigation of human epidermis in the longitudinal course of AD therapy. We could ascertain by blinded analysis of 40 skin areas of 20 patients in a three month follow-up that the metabolic status at the SC/SG interface was altered in AD compromised skin even in non-lesional, apparent healthy skin regions. This illustrates an impaired skin barrier formation even at non-affected skin of AD subjects appearing promotive for the development of acute skin inflammation. Therefore, our findings allow a deeper understanding of the individual disease development and the improved management of the therapeutic intervention in clinical application.

  19. In-vivo fluorescence dosimetry of aminolevulinate-based protoporphyrin IX (PpIX) accumulation in human nonmelanoma skin cancers and precancers

    NASA Astrophysics Data System (ADS)

    Warren, Christine B.; Lohser, Sara; Chang, Sung; Bailin, Philip A.; Maytin, Edward V.

    2009-06-01

    PDT is clinically useful for precancers (actinic keratoses; AK) of the skin, but the optimal duration for 5-ALA application is still controversial. For basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), cure rates remain inferior to surgical excision. Lack of knowledge about regional levels of PpIX levels within target tissues clearly contribute to these suboptimal results. To investigate PpIX levels achievable in human skin neoplasias in-vivo, a clinical study to monitor PpIX accumulation in vivo was performed. PpIX-fluorescence in patients undergoing ALA-PDT for facial AK was monitored via real-time in-vivo fluorescence dosimetry, with measurements q20 min following application of 5-ALA (Levulan Kerastick). PpIX accumulation followed linear kinetics in nearly all cases. The slopes varied widely, and did not correlate with clinical outcome in all patients. Some patients with a low accumulation of PpIX fluorescence had a good response to therapy, whereas others with high PpIX accumulation required repeat treatment (although not necessarily of the same lesion). PpIX accumulation rates did correlate to a certain degree with the overall amount of erythema. We conclude that unknown factors besides PpIX levels must be critical for the response to treatment. To assess the relationship between PpIX levels in various skin cancers, patients undergoing routine Mohs surgery for BCC or SCC were measured by in-vivo dosimetry at 2 h after 5-ALA application. Overall, a progressive increase in PpIX signal during malignant progression was observed, in the following rank order: Normal skin < AK < SCC ~ BCC.

  20. In vivo percutaneous absorption of boric acid, borax, and disodium octaborate tetrahydrate in humans compared to in vitro absorption in human skin from infinite and finite doses.

    PubMed

    Wester, R C; Hui, X; Hartway, T; Maibach, H I; Bell, K; Schell, M J; Northington, D J; Strong, P; Culver, B D

    1998-09-01

    Literature from the first half of this century report concern for toxicity from topical use of boric acid, but assessment of percutaneous absorption has been impaired by lack of analytical sensitivity. Analytical methods in this study included inductively coupled plasma-mass spectrometry which now allows quantitation of percutaneous absorption of 10B in 10B-enriched boric acid, borax, and disodium octaborate tetrahydrate (DOT) in biological matrices. This made it possible, in the presence of comparatively large natural dietary boron intakes for the in vivo segment of this study, to quantify the boron passing through skin. Human volunteers were dosed with 10B-enriched boric acid, 5.0%, borax, 5.0%, or disodium octaborate tetrahydrate, 10%, in aqueous solutions. Urinalysis, for boron and changes in boron isotope ratios, was used to measure absorption. Boric acid in vivo percutaneous absorption was 0.226 (SD = 0.125) mean percentage dose, with flux and permeability constant (Kp) calculated at 0.009 microgram/cm2/h and 1.9 x 10(-7) cm/h, respectively. Borax absorption was 0.210 (SD = 0.194) mean percentage of dose, with flux and Kp calculated at 0.009 microgram/cm2/h and 1.8 x 10(-7) cm/h, respectively. DOT absorption was 0.122 (SD = 0.108) mean percentage, with flux and Kp calculated at 0.01 microgram/cm2/h and 1.0 x 10(-7) cm/h, respectively. Pretreatment with the potential skin irritant 2% sodium lauryl sulfate had no effect on boron skin absorption. In vitro human skin percentage of doses of boric acid absorbed were 1.2 for a 0.05% solution, 0.28 for a 0.5% solution, and 0.70 for a 5.0% solution. These absorption amounts translated into flux values of, respectively, 0.25, 0.58, and 14.58 micrograms/cm2/h and permeability constants (Kp) of 5.0 x 10(-4), 1.2 x 10(-4), and 2.9 x 10(-4) cm/h for the 0.05, 0.5, and 5.0% solutions. The above in vitro doses were at infinite, 1000 microliters/cm2 volume. At 2 microliters/cm2 (the in vivo dosing volume), flux decreased some

  1. In vivo multiphoton imaging of human skin: assessment of topical corticosteroid-induced epidermis atrophy and depigmentation

    NASA Astrophysics Data System (ADS)

    Ait El Madani, Hassan; Tancrède-Bohin, Emmanuelle; Bensussan, Armand; Colonna, Anne; Dupuy, Alain; Bagot, Martine; Pena, Ana-Maria

    2012-02-01

    Multiphoton microscopy has emerged in the past decade as a promising tool for noninvasive skin imaging. Our aim was to evaluate the potential of multiphoton microscopy to detect topical corticosteroids side effects within the epidermis and to provide new insights into their dynamics. Healthy volunteers were topically treated with clobetasol propionate on a small region of their forearms under overnight occlusion for three weeks. The treated region of each patient was investigated at D0, D7, D15, D22 (end of the treatment), and D60. Our study shows that multiphoton microscopy allows for the detection of corticoid-induced epidermis modifications: thinning of stratum corneum compactum and epidermis, decrease of keratinocytes size, and changes in their morphology from D7 to D22. We also show that multiphoton microscopy enables in vivo three-dimensional (3-D) quantitative assessment of melanin content. We observe that melanin density decreases during treatment and almost completely disappears at D22. Moreover, these alterations are reversible as they are no longer present at D60. Our study demonstrates that multiphoton microscopy is a convenient and powerful tool for noninvasive 3-D dynamical studies of skin integrity and pigmentation.

  2. Skin metabolism of aminophenols: Human keratinocytes as a suitable in vitro model to qualitatively predict the dermal transformation of 4-amino-2-hydroxytoluene in vivo

    SciTech Connect

    Goebel, C. Hewitt, N.J.; Kunze, G.; Wenker, M.; Hein, D.W.; Beck, H.; Skare, J.

    2009-02-15

    4-Amino-2-hydroxytolune (AHT) is an aromatic amine ingredient in oxidative hair colouring products. As skin contact occurs during hair dyeing, characterisation of dermal metabolism is important for the safety assessment of this chemical class. We have compared the metabolism of AHT in the human keratinocyte cell line HaCaT with that observed ex-vivo in human skin and in vivo (topical application versus oral (p.o.) and intravenous (i.v.) route). Three major metabolites of AHT were excreted, i.e. N-acetyl-AHT, AHT-sulfate and AHT-glucuronide. When 12.5 mg/kg AHT was applied topically, the relative amounts of each metabolite were altered such that N-acetyl-AHT product was the major metabolite (66% of the dose in comparison with 37% and 32% of the same applied dose after i.v. and p.o. administration, respectively). N-acetylated products were the only metabolites detected in HaCaT cells and ex-vivo whole human skin discs for AHT and p-aminophenol (PAP), an aromatic amine known to undergo N-acetylation in vivo. Since N-acetyltransferase 1 (NAT1) is the responsible enzyme, kinetics of AHT was further compared to the standard NAT1 substrate p-aminobenzoic acid (PABA) in the HaCaT model revealing similar values for K{sub m} and V{sub max}. In conclusion NAT1 dependent dermal N-acetylation of AHT represents a 'first-pass' metabolism effect in the skin prior to entering the systemic circulation. Since the HaCaT cell model represents a suitable in vitro assay for addressing the qualitative contribution of the skin to the metabolism of topically-applied aromatic amines it may contribute to a reduction in animal testing.

  3. Mean cell size and collagen orientation from 2D Fourier analysis on confocal laser scanning microscopy and two-photon fluorescence microscopy on human skin in vivo

    NASA Astrophysics Data System (ADS)

    Lucassen, Gerald W.; Bakker, Bernard L.; Neerken, Sieglinde; Hendriks, Rob F. M.

    2003-07-01

    We present results from 2D Fourier analysis on 3D stacks of images obtained by confocal laser scanning reflectance microscopy (CLSM) and two-photon fluorescence microscopy (2PM) on human skin in vivo. CLSM images were obtained with a modified commercial system (Vivascope1000, Lucid Inc, excitation wavelength 830 nm) equipped with a piezo-focusing element (350 μm range) for depth positioning of the objective lens. 2PM was performed with a specially designed set-up with excitation wavelength 730 nm. Mean cell size in the epidermal layer and structural orientation in the dermal layer have been determined as a function of depth by 2D Fourier analysis. Fourier analysis on microscopic images enables automatic non-invasive quantitative structural analysis (mean cell size and orientation) of living human skin.

  4. Evaluating the Photoprotective Effects of Ochre on Human Skin by In Vivo SPF Assessment: Implications for Human Evolution, Adaptation and Dispersal

    PubMed Central

    Rifkin, Riaan F.; Dayet, Laure; Queffelec, Alain; Summers, Beverley; Lategan, Marlize; d’Errico, Francesco

    2015-01-01

    Archaeological indicators of cognitively modern behaviour become increasingly prevalent during the African Middle Stone Age (MSA). Although the exploitation of ochre is viewed as a key feature of the emergence of modern human behaviour, the uses to which ochre and ochre-based mixtures were put remain ambiguous. Here we present the results of an experimental study exploring the efficacy of ochre as a topical photoprotective compound. This is achieved through the in vivo calculation of the sun protection factor (SPF) values of ochre samples obtained from Ovahimba women (Kunene Region, Northern Namibia) and the Palaeozoic Bokkeveld Group deposits of the Cape Supergroup (Western Cape Province, South Africa). We employ visible spectroscopy, energy-dispersive X-ray fluorescence (ED-XRF), X-ray diffraction (XRD) and granulometric analyses to characterise ochre samples. The capacity of ochre to inhibit the susceptibility of humans to the harmful effects of exposure to ultraviolet radiation (UVR) is confirmed and the mechanisms implicated in the efficacy of ochre as a sunscreen identified. It is posited that the habitual application of ochre may have represented a crucial innovation for MSA humans by limiting the adverse effects of ultraviolet exposure. This may have facilitated the colonisation of geographic regions largely unfavourable to the constitutive skin colour of newly arriving populations. PMID:26353012

  5. Evaluating the Photoprotective Effects of Ochre on Human Skin by In Vivo SPF Assessment: Implications for Human Evolution, Adaptation and Dispersal.

    PubMed

    Rifkin, Riaan F; Dayet, Laure; Queffelec, Alain; Summers, Beverley; Lategan, Marlize; d'Errico, Francesco

    2015-01-01

    Archaeological indicators of cognitively modern behaviour become increasingly prevalent during the African Middle Stone Age (MSA). Although the exploitation of ochre is viewed as a key feature of the emergence of modern human behaviour, the uses to which ochre and ochre-based mixtures were put remain ambiguous. Here we present the results of an experimental study exploring the efficacy of ochre as a topical photoprotective compound. This is achieved through the in vivo calculation of the sun protection factor (SPF) values of ochre samples obtained from Ovahimba women (Kunene Region, Northern Namibia) and the Palaeozoic Bokkeveld Group deposits of the Cape Supergroup (Western Cape Province, South Africa). We employ visible spectroscopy, energy-dispersive X-ray fluorescence (ED-XRF), X-ray diffraction (XRD) and granulometric analyses to characterise ochre samples. The capacity of ochre to inhibit the susceptibility of humans to the harmful effects of exposure to ultraviolet radiation (UVR) is confirmed and the mechanisms implicated in the efficacy of ochre as a sunscreen identified. It is posited that the habitual application of ochre may have represented a crucial innovation for MSA humans by limiting the adverse effects of ultraviolet exposure. This may have facilitated the colonisation of geographic regions largely unfavourable to the constitutive skin colour of newly arriving populations.

  6. Three-dimensional full-range complex Fourier domain optical coherence tomography for in-vivo volumetric imaging of human skin

    NASA Astrophysics Data System (ADS)

    Nan, Nan; Bu, Peng; Guo, Xin; Wang, Xiangzhao

    2011-11-01

    A three dimensional full-range complex Fourier domain optical coherence tomography (complex FDOCT) system based on sinusoidal phase-modulating method is proposed. With the system, the range of imaging depth is doubled and the sensitivity degradation with the lateral scan distance is avoided. Fourier analysis of B-scan data along lateral scan distance is used for reconstructing the complex spectral interferograms. The B-scan based Fourier method improves the system tolerance of sample movement and makes data processing less time consuming. In vivo volumetric imaging of human skin with the proposed full-range FDOCT system is demonstrated. The mirror image rejection ratio is about 30 dB. The stratum corneum, the epidermis and the upper dermis of skin can be clearly identified in the reconstructed three dimensional FDOCT images.

  7. Three-dimensional full-range complex Fourier domain optical coherence tomography for in-vivo volumetric imaging of human skin

    NASA Astrophysics Data System (ADS)

    Nan, Nan; Bu, Peng; Guo, Xin; Wang, Xiangzhao

    2012-03-01

    A three dimensional full-range complex Fourier domain optical coherence tomography (complex FDOCT) system based on sinusoidal phase-modulating method is proposed. With the system, the range of imaging depth is doubled and the sensitivity degradation with the lateral scan distance is avoided. Fourier analysis of B-scan data along lateral scan distance is used for reconstructing the complex spectral interferograms. The B-scan based Fourier method improves the system tolerance of sample movement and makes data processing less time consuming. In vivo volumetric imaging of human skin with the proposed full-range FDOCT system is demonstrated. The mirror image rejection ratio is about 30 dB. The stratum corneum, the epidermis and the upper dermis of skin can be clearly identified in the reconstructed three dimensional FDOCT images.

  8. A comparison of the in vivo effects of ketotifen, clemastine, chlorpheniramine and sodium cromoglycate on histamine and allergen induced weals in human skin.

    PubMed Central

    Phillips, M J; Meyrick Thomas, R H; Moodley, I; Davies, R J

    1983-01-01

    The effect of ketotifen was compared with that of clemastine and chlorpheniramine, known antihistamines, and sodium cromoglycate, a drug considered to have mast cell "stabilizing' properties on histamine and allergen wealing reactions in human skin, in random order, double-blind, placebo controlled studies. Ketotifen was significantly more potent in the inhibition of both histamine (P less than 0.001) and allergen (P less than 0.001) skin wealing reactions than either clemastine or chlorpheniramine. Sodium cromoglycate had no significant effect on either histamine or allergen skin wealing reactions in any of the concentrations tested. However ketotifen, like clemastine, had a significantly greater inhibitory effect on histamine than on allergen induced weals (P less than 0.001) and both drugs were shown to act as competitive antagonists of histamine. Ketotifen has been shown to be a potent anti-histamine but there is no evidence from these in vivo studies to suggest that it has any additional inhibitory activity on release of mediators from mast cells in human skin. PMID:6405771

  9. Dose-dependent vitamin C uptake and radical scavenging activity in human skin measured with in vivo electron paramagnetic resonance spectroscopy.

    PubMed

    Lauer, Anna-Christina; Groth, Norbert; Haag, Stefan F; Darvin, Maxim E; Lademann, Jürgen; Meinke, Martina C

    2013-01-01

    Vitamin C is a potent radical scavenger and a physiological part of the antioxidant system in human skin. The aim of this study was to measure changes in the radical-scavenging activity of human skin in vivo due to supplementation with different doses of vitamin C and at different time points. Therefore, 33 volunteers were supplemented with vitamin C or placebo for 4 weeks. The skin radical-scavenging activity was measured with electron paramagnetic resonance spectroscopy. After 4 weeks, the intake of 100 mg vitamin C/day resulted in a significant increase in the radical-scavenging activity by 22%. Intake of 180 mg/day even resulted in a significant increase of 37%. No changes were found in the placebo group. A part of the study population was additionally measured after 2 weeks: in this group radical scavenging had already reached maximal activity after 2 weeks. In conclusion, orally administered vitamin C increases the radical-scavenging activity of the skin. The effect occurs fast and is enhanced with higher doses of vitamin C.

  10. Increased epidermal cell proliferation in normal human skin in vivo following local administration of interferon-gamma.

    PubMed Central

    Barker, J. N.; Goodlad, J. R.; Ross, E. L.; Yu, C. C.; Groves, R. W.; MacDonald, D. M.

    1993-01-01

    Recombinant human interferon-gamma was administered intradermally (10 micrograms in 0.1 ml) to healthy adult human volunteers from day 1 to day 3, and epidermal cell proliferation was measured on whole skin biopsies at day 6. Three independent parameters were assessed, namely, a) epidermal keratin-16 expression, b) keratinocyte proliferating cell nuclear antigen expression, and c) keratinocyte silver nucleolar organizer region counts. Significantly increased scores for each parameter were observed after interferon-gamma injection (P < 0.01 in each case) compared to site-matched controls. Keratin-16 expression was confined to suprabasal epidermis, whereas proliferating cell nuclear antigen and silver nucleolar organizer region counts were particularly elevated in the basal epidermis. Taken together with previous findings, these studies indicate both proinflammatory and growth regulatory roles for interferon-gamma in human skin. These data are likely to be of particular importance to pathophysiological mechanisms of psoriasis and related cutaneous inflammatory diseases. Images Figure 1 Figure 2 Figure 3 PMID:7682760

  11. Influence of age and sun exposure on the biophysical properties of the human skin: an in vivo study.

    PubMed

    Adhoute, H; de Rigal, J; Marchand, J P; Privat, Y; Leveque, J L

    1992-06-01

    The physical properties of the skin were measured by using noninvasive methods on 72 people displaying various levels of solar elastosis on the neck. The physical parameters measured were the skin extensibility, the elastic recovery, the skin colour, the skin thickness and the electrical conductance. The correlation between the above parameters, the clinical grades of elastosis and the chronological age of each subject were studied using two different statistical approaches. They both showed that elastotic skin is less elastic, dryer, darker, more erythematous and less yellowish than the nonexposed skin. The similarities and differences between the properties of elastotic skin and purely chronologically aged skin are discussed.

  12. Impact of refractive index mismatches on coherent anti-Stokes Raman scattering and multiphoton autofluorescence tomography of human skin in vivo.

    PubMed

    Weinigel, M; Breunig, H G; Darvin, M E; Klemp, M; Röwert-Huber, J; Lademann, J; König, K

    2015-09-07

    Optical non-linear multimodal tomography is a powerful diagnostic imaging tool to analyse human skin based on its autofluorescence and second-harmonic generation signals. Recently, the field of clinical non-linear imaging has been extended by adding coherent anti-Stokes Raman scattering (CARS)-a further optical sectioning method for the detection of non-fluorescent molecules. However, the heterogeneity of refractive indices of different substances in complex tissues like human skin can have a strong influence on CARS image formation and requires careful clinical interpretation of the detected signals. Interestingly, very regular patterns are present in the CARS images, which have no correspondence to the morphology revealed by autofluorescence at the same depth. The purpose of this paper is to clarify this phenomenon and to sensitize users for possible artefacts. A further part of this paper is the detailed comparison of CARS and autofluorescence images of healthy human skin in vivo covering the complete epidermis and part of the upper dermis by employing the flexible medical non-linear tomograph MPTflex CARS.

  13. 5D-intravital tomography as a novel tool for non-invasive in-vivo analysis of human skin

    NASA Astrophysics Data System (ADS)

    König, Karsten; Weinigel, Martin; Breunig, Hans G.; Gregory, Axel; Fischer, Peter; Kellner-Höfer, Marcel; Bückle, Rainer; Schwarz, Martin; Riemann, Iris; Stracke, Frank; Huck, Volker; Gorzelanny, Christian; Schneider, Stefan W.

    2010-02-01

    Some years ago, CE-marked clinical multiphoton systems for 3D imaging of human skin with subcellular resolution have been launched. These tomographs provide optical biopsies with submicron resolution based on two-photon excited autofluorescence (NAD(P)H, flavoproteins, keratin, elastin, melanin, porphyrins) and second harmonic generation by collagen. The 3D tomograph was now transferred into a 5D imaging system by the additional detection of the emission spectrum and the fluorescence lifetime based on spatially and spectrally resolved time-resolved single photon counting. The novel 5D intravital tomograph (5D-IVT) was employed for the early detection of atopic dermatitis and the analysis of treatment effects.

  14. Dose-survival relationship for epithelial cells of human skin after multifraction irradiation: evaluation by a quantitative method in vivo

    SciTech Connect

    Arcangeli, G.; Mauro, F.; Nervi, C.; Withers, H.R.

    1980-07-01

    The dose-survival relationship for normal epithelial cells after single and fractionated radiation exposures has been established by Withers for the mouse, but it is not available for humans according to a strict criterion for survival of single cell reproductive integrity. In an attempt to obtain such a quantitative estimation, 2 patients requiring radical radiation therapy to the chest wall were treated according to particular Multiple Daily Fractionation (MDF) protocols: i) 250 + 150 + 150 rad/day, 4 hr interval, 5 days/week; and ii) 150 + 150 + 150 + 150 rad/day, 3.5 hr interval, 5 days/week. In both cases, different strips of skin received different total doses: 6300, 6850, and 7150 rad, and 6300, 6750, and 7200 rad, respectively. In case (i), moist desquamation appeared and thereafter repopulating colonies of epithelium could be recognized and counted. Using these counts a survival curve having a D/sub o/ value of 490 +- 150 rad was estimated according to the formula proposed by Withers. In case (ii), no moist desquamation was reached at the doses delivered. The difference observed may imply that the initial region of the survival curve deviates appreciably from exponential between doses of 150 and 250 rad. If such is the case, a /sub 1/D/sub o/ value of 490 rad may represent an underestimate. These results are discussed from the point of view of both the shape of the survival curve and the effectiveness of nonconventional fractionation courses.

  15. In vitro and in vivo comparison of dermal irritancy of jet fuel exposure using EpiDerm (EPI-200) cultured human skin and hairless rats.

    PubMed

    Chatterjee, Abhijit; Babu, R Jayachandra; Klausner, M; Singh, Mandip

    2006-12-01

    The purpose of this study was to evaluate an in vitro EpiDerm human skin model (EPI-200) to study the irritation potential of jet fuels (JP-8 and JP-8+100). Parallel in vivo studies on hairless rats on the dermal irritancy of jet fuels were also conducted. Cytokines are an important part of an irritation and inflammatory cascade, which are expressed in upon dermal exposures of irritant chemicals even when there are no obvious visible marks of irritation on the skin. We have chosen two primary cytokines (IL-1alpha and TNF-1alpha) as markers of irritation response of jet fuels. Initially, the EPI-200 was treated with different quantities of JP-8 and JP-8+100 to determine quantities which did not cause significant cytotoxicity, as monitored using the MTT assay and paraffin embedded histological cross-sections. Volumes of 2.5-50 microl/tissue (approximately 4.0-78 microl/cm2) of JP-8 and JP-8+100 showed a dose dependent loss of tissue viability and morphological alterations of the tissue. At a quantity of 1.25 microl/tissue (approximately 2.0 microl/cm2), no significant change in tissue viability or morphology was observed for exposure time extending to 48 h. Nonetheless, this dose induced significant increase in IL-1alpha and TNF-alpha release versus non-treated controls after 24 and 48 h. In addition, IL-1alpha release for JP-8+100 was significantly higher than that observed for JP-8, but TNF-alpha release after 48 h exposure to these two jet fuels was the same. These findings parallel in vivo studies on hairless rats, which indicated higher irritation levels due to JP-8+100 versus JP-8. In vivo, transepidermal water loss (TEWL) and IL-1alpha expression levels followed the order JP-8+100 > JP-8 > control. Further, in vivo TNF-alpha levels for JP-8 and JP-8+100 were also elevated but not significantly different from one another. In aggregate, these findings indicate that EPI-200 tissue model can be utilized as an alternative to the use of animals in evaluating dermal

  16. A modified algorithm for continuous wave near infrared spectroscopy applied to in-vivo animal experiments and on human skin

    NASA Astrophysics Data System (ADS)

    Klaessens, John H. G. M.; Hopman, Jeroen C. W.; Liem, K. Djien; de Roode, Rowland; Verdaasdonk, Rudolf M.; Thijssen, Johan M.

    2008-02-01

    Continuous wave Near Infrared Spectroscopy is a well known non invasive technique for measuring changes in tissue oxygenation. Absorption changes (ΔO2Hb and ΔHHb) are calculated from the light attenuations using the modified Lambert Beer equation. Generally, the concentration changes are calculated relative to the concentration at a starting point in time (delta time method). It is also possible, under certain assumptions, to calculate the concentrations by subtracting the equations at different wavelengths (delta wavelength method). We derived a new algorithm and will show the possibilities and limitations. In the delta wavelength method, the assumption is that the oxygen independent attenuation term will be eliminated from the formula even if its value changes in time, we verified the results with the classical delta time method using extinction coefficients from different literature sources for the wavelengths 767nm, 850nm and 905nm. The different methods of calculating concentration changes were applied to the data collected from animal experiments. The animals (lambs) were in a stable normoxic condition; stepwise they were made hypoxic and thereafter they returned to normoxic condition. The two algorithms were also applied for measuring two dimensional blood oxygen saturation changes in human skin tissue. The different oxygen saturation levels were induced by alterations in the respiration and by temporary arm clamping. The new delta wavelength method yielded in a steady state measurement the same changes in oxy and deoxy hemoglobin as the classical delta time method. The advantage of the new method is the independence of eventual variation of the oxygen independent attenuations in time.

  17. Quercus suber cork extract displays a tensor and smoothing effect on human skin: an in vivo study.

    PubMed

    Coquet, C; Bauza, E; Oberto, G; Berghi, A; Farnet, A M; Ferré, E; Peyronel, D; Dal Farra, C; Domloge, N

    2005-01-01

    Recently, it has become indispensable for anti-aging active ingredients to provide a visible and immediate smoothing antiwrinkle effect. In Quercus suber, suberin is the most important structural component of cork cell walls. Studies have shown that suberin is made up mostly of hydroxycarboxylic acids and that it is endowed with many special mechanical and chemical properties that evoke a possible smoothing effect on the surface of the skin. Therefore, we were interested in investigating the effect of this cork extract on the skin's surface in a double-blind clinical study. The study was conducted in 15 healthy volunteers, aged 22 to 52 years. The volunteers applied a gel formula with 3% of cork extract, or placebo gel, on each forearm. Skin surface roughness was evaluated visually by pictures and by silicone replicas 1 and 2 h after application, followed by statistical analysis using the matched-pairs McNemar statistical test. McNemar analysis of the pictures revealed that application of cork extract on the skin resulted in a highly significant reduction of roughness 1 h after application. This effect was observed in 73.3% of volunteers. Two hours after cork extract application, a highly significant improvement of skin roughness was found in 78.6% of volunteers. Moreover, silicone replica treatment confirmed significant improvement in average of roughness at 2 h. These results demonstrate that cork extract provides a remarkable and highly significant tensor and smoothing effect on the skin, which could be of great use in anti-aging skin care products.

  18. Confocal imaging of benign and malignant proliferative skin lesions in vivo

    NASA Astrophysics Data System (ADS)

    Gonzalez, Salvador; Rajadhyaksha, Milind M.; Anderson, R. Rox

    1999-06-01

    Near-infrared confocal reflectance microscopy (CM) provides non- invasive real-time images of thin en-face tissue sections with high resolution and contrast. Imaging of cells, nuclei, other organelles, microvessels, and hair follicles has been possible at resolution comparable to standard histology, to a maximum depth of 250-300 μm in human skin in vivo. We have characterized psoriasis as a prototype of benign proliferative skin conditions, and non-pigmented skin malignancies in vivo based on their unstained, native histologic features using CM. Our data shows that reflectance CM may potentially diagnose and morphometrically evaluate proliferative skin lesions in vivo.

  19. Kinetics of carotenoid distribution in human skin in vivo after exogenous stress: disinfectant and wIRA-induced carotenoid depletion recovers from outside to inside

    NASA Astrophysics Data System (ADS)

    Fluhr, Joachim W.; Caspers, Peter; van der Pol, J. Andre; Richter, Heike; Sterry, Wolfram; Lademann, Juergen; Darvin, Maxim E.

    2011-03-01

    The human organism has developed a protection system against the destructive effect of free radicals. The aim of the present study was to investigate the extent of exogenous stress factors such as disinfectant and IR-A radiation on the skin, and their influence on the kinetics of carotenoids distribution during the recovery process. Ten healthy volunteers were assessed with resonance spectroscopy using an Argon-laser at 488 nm to excite the carotenoids in vivo. Additionally, Raman-confocal-micro-spectroscopy measurements were performed using a model 3510 Skin Composition Analyzer with spatially resolved measurements down to 30 μm. The measurements were performed at a baseline of 20, 40, 60, and 120 min after an external stressor consisting either of water-filtered infrared A (wIRA) with 150 mW/cm2 or 1 ml/cm2 of an alcoholic disinfectant. Both Raman methods were capable to detect the infrared-induced depletion of carotenoids. Only Raman-microspectroscopy could reveal the carotenoids decrease after topical disinfectant application. The carotenoid-depletion started at the surface. After 60 min, recovery starts at the surface while deeper parts were still depleted. The disinfectant- and wIRA-induced carotenoid depletion in the epidermis recovers from outside to inside and probably delivered by sweat and sebaceous glands. We could show that the Raman microscopic spectroscopy is suited to analyze the carotenoid kinetic of stress effects and recovery.

  20. Feasibility of measuring arsenic and selenium in human skin using in vivo x-ray fluorescence (XRF)--a comparison of methods.

    PubMed

    Shehab, H; Desouza, E D; O'Meara, J; Pejović-Milić, A; Chettle, D R; Fleming, D E B; McNeill, F E

    2016-01-01

    In recent years, in vivo measurement systems of arsenic in skin by K-shell x-ray fluorescence (XRF) have been developed, including one which was applied in a pilot study of human subjects. Improved tube-based approaches suggest the method can be further exploited for in vivo studies. Recently, it has been suggested that selenium deficiency is correlated with arsenic toxicity. A non-invasive measurement of both elements could therefore be of potential interest. The main aim of this current study was to evaluate and compare the performance of an upgraded portable XRF system and an advanced version of the benchtop XRF system for both selenium and arsenic. This evaluation was performed in terms of arsenic and selenium Kα detection limits for a 4W gold anode Olympus InnovX Delta portable analyzer (40 kVp) in polyester resin skin-mimicking phantoms. Unlike the polychromatic source earlier reported in the literature, the benchtop tube-based technique involves monochromatic excitation (25 W silver anode, manufactured by x-ray optics, XOS) and a higher throughput detector type. Use of a single exciting energy allows for a lower in vivo dose delivered and superior signal-noise ratio. For the portable XRF method, arsenic and selenium minimum detection limits (MDLs) of 0.59  ±  0.03 ppm and 0.75  ±  0.02 ppm respectively were found for 1 min measurement times. The MDLs for arsenic and selenium using the benchtop system were found to be 0.35  ±  0.01 ppm and 0.670  ±  0.004 ppm respectively for 30 min measurement times. In terms of a figure of merit (FOM), allowing for dose as well as MDL, the benchtop system was found to be superior for arsenic and the two systems were equivalent, within error, for selenium. We shall discuss the performance and possible improvements of each system, their ease of use and potential for field application.

  1. Setup and dosimetry for exposure of human skin in vivo to RF-EMF at 900 MHz.

    PubMed

    Toivonen, Tommi; Toivo, Tim; Puranen, Lauri; Jokela, Kari

    2008-04-01

    The aim of this study was a dosimetrical analysis of an experimental setup used in the exposure of 10 female volunteers to GSM 900 radiation. The exposure was carried out by irradiating a small region of the right forearms of the volunteers for 1 h, after which biopsies were taken from the exposed skin for protein analysis. The source of irradiation was a half-wave dipole fed with a computer controlled GSM phone. The specific absorption rate (SAR) induced in the skin biopsy was assessed by computer simulations. The numerical model of the arm consisted of a muscle tissue simulating cylinder covered with thin skin (1 mm) and fat (3 mm) layers. The simulation models were validated by measurements with a homogeneous cylindrical liquid phantom. The average SAR value in the biopsy was 1.3 W/kg and the estimated uncertainty +/-20% (K = 2). The main source of error was found to be variations in the distance of the forearm from the dipole (10 +/- 1 mm). Other significant sources of uncertainty are individual variations of the fat layer and arm thicknesses, and the uncertainty of radio frequency (RF) power measurement.

  2. Dexpanthenol modulates gene expression in skin wound healing in vivo.

    PubMed

    Heise, R; Skazik, C; Marquardt, Y; Czaja, K; Sebastian, K; Kurschat, P; Gan, L; Denecke, B; Ekanayake-Bohlig, S; Wilhelm, K-P; Merk, H F; Baron, J M

    2012-01-01

    Topical application of dexpanthenol is widely used in clinical practice for the improvement of wound healing. Previous in vitro experiments identified a stimulatory effect of pantothenate on migration, proliferation and gene regulation in cultured human dermal fibroblasts. To correlate these in vitro findings with the more complex in vivo situation of wound healing, a clinical trial was performed in which the dexpanthenol-induced gene expression profile in punch biopsies of previously injured and dexpanthenol-treated skin in comparison to placebo-treated skin was analyzed at the molecular level by Affymetrix® GeneChip analysis. Upregulation of IL-6, IL-1β, CYP1B1, CXCL1, CCL18 and KAP 4-2 gene expression and downregulation of psorasin mRNA and protein expression were identified in samples treated topically with dexpanthenol. This in vivo study might provide new insight into the molecular mechanisms responsible for the effect of dexpanthenol in wound healing and shows strong correlations to previous in vitro data using cultured dermal fibroblasts.

  3. Skin thickness effects on in vivo LXRF

    SciTech Connect

    Preiss, I.L.; Washington, W. II

    1995-12-31

    The analysis of lead concentration in bone utilizing LXRF can be adversely effected by overlying issue. A quantitative measure of the attenuation of the 10.5 keV Pb L a x-ray signal by skin and skin equivalent plastic has been conducted. Concentration ranges in plaster of Paris and goat bone from 7 to 90 ppm with attenuators of Lucite{reg_sign} and pig skin were examined. It is concluded that no quantitative or semi quantitative analysis can be achieved if overlying sue thickness exceeds 3 mm for Ph concentrations of less than 30 porn Ph in bone.

  4. Fluorescence spectral imaging of dihydroxyacetone on skin in vivo.

    PubMed

    Forest, Susan E; Grothaus, Jeff T; Ertel, Keith D; Rader, Charlie; Plante, Janyl

    2003-05-01

    Dihydroxyacetone (DHA) has been proposed as a potential alternative to dansyl chloride for use as a fluorescence marker on skin to assess stratum corneum turnover time in vivo. However, the fluorescence from DHA on skin has not been adequately studied. To address this void, a noninvasive, noncontact spectral imaging system is used to characterize the fluorescence spectrum of DHA on skin in vivo and to determine the optimal wavelengths over which to collect the DHA signal that minimizes the contributions from skin autofluorescence. The DHA-skin fluorescence signal dominates the 580-680 nm region of the visible spectrum when excited with ultraviolet radiation in the 320-400 nm wavelength region (UVA). An explanation of the time-dependent spectral features is proposed in terms of DHA polymerization and binding to skin.

  5. Percutaneous absorption of nicotinic acid, phenol, benzoic acid and triclopyr butoxyethyl ester through rat and human skin in vitro: further validation of an in vitro model by comparison with in vivo data.

    PubMed

    Hotchkiss, S A; Hewitt, P; Caldwell, J; Chen, W L; Rowe, R R

    1992-10-01

    The in vitro percutaneous absorption of three model compounds, nicotinic acid, phenol and benzoic acid, and the herbicide triclopyr butoxyethyl ester (triclopyr BEE) has been investigated in flow-through diffusion cells using skin from male Fischer 344 rats and humans. After the application of the four chemicals to the epidermal surface of unoccluded full-thickness rat skin, the absorption of each compound across the skin and into the receptor fluid at 72 hr reached 3.7 +/- 0.3, 5.7 +/- 0.6, 26.7 +/- 3.7 and 48.3 +/- 1.2% (mean +/- SD, n = 2-7) of the applied dose for triclopyr BEE, nicotinic acid, phenol and benzoic acid, respectively. After the application of the four chemicals to the epidermal surface of unoccluded full-thickness human skin, the absorption of each compound across the skin and into the receptor fluid at 72 hr was significantly (P < 0.05) less than through rat skin, reaching 0.7 +/- 0.1, 0.7 +/- 0.2, 18.8 +/- 1.3 and 37.8 +/- 6.9% (mean +/- SD, n = 2-7) of the applied dose for triclopyr BEE, nicotinic acid, phenol and benzoic acid, respectively. Occlusion of the skin surface with teflon caps often significantly (P < 0.05) enhanced the percutaneous absorption of the model compounds, although this effect was not uniform, varying with the compound under study and the skin (rat or human) used. When rat skin was occluded with teflon caps, the extent of absorption at 72 hr reached 8.6 +/- 0.8, 36.2 +/- 1.7 and 51.8 +/- 3.3% (mean +/- SD, n = 3-4) for nicotinic acid, phenol and benzoic acid, respectively. Corresponding values for human skin occluded with teflon caps were 3.3 +/- 1.6, 47.1 +/- 0.5 and 65.5 +/- 7.1% (mean +/- SD, n = 3-4). The experiments on the absorption of each model compound through rat and human skin were repeated and there was generally good agreement between the results from the two sets of experiments. The in vitro data reported compare favourably with data obtained by other workers using both in vitro and in vivo methodologies

  6. In vivo multiphoton tomography of skin cancer

    NASA Astrophysics Data System (ADS)

    König, Karsten; Riemann, Iris; Ehlers, Alexander; Buckle, Rainer; Dimitrow, Enrico; Kaatz, Martin; Fluhr, Joachim; Elsner, Peter

    2006-02-01

    The multiphoton tomograph DermaInspect was used to perform first clinical studies on the early non-invasive detection of skin cancer based on non-invasive optical sectioning of skin by two-photon autofluorescence and second harmonic generation. In particular, deep-tissue pigmented lesions -nevi- have been imaged with intracellular resolution using near infrared (NIR) femtosecond laser radiation. So far, more than 250 patients have been investigated. Cancerous tissues showed significant morphological differences compared to normal skin layers. In the case of malignant melanoma, the occurrence of luminescent melanocytes has been detected. Multiphoton tomography will become a novel non-invasive method to obtain high-resolution 3D optical biopsies for early cancer detection, treatment control, and in situ drug screening.

  7. Reconstructing in-vivo reflectance spectrum of pigmented skin lesion by Monte Carlo simulation

    NASA Astrophysics Data System (ADS)

    Wang, Shuang; He, Qingli; Zhao, Jianhua; Lui, Harvey; Zeng, Haishan

    2012-03-01

    In dermatology applications, diffuse reflectance spectroscopy has been extensively investigated as a promising tool for the noninvasive method to distinguish melanoma from benign pigmented skin lesion (nevus), which is concentrated with the skin chromophores like melanin and hemoglobin. We carried out a theoretical study to examine melanin distribution in human skin tissue and establish a practical optical model for further pigmented skin investigation. The theoretical simulation was using junctional nevus as an example. A multiple layer skin optical model was developed on established anatomy structures of skin, the published optical parameters of different skin layers, blood and melanin. Monte Carlo simulation was used to model the interaction between excitation light and skin tissue and rebuild the diffuse reflectance process from skin tissue. A testified methodology was adopted to determine melanin contents in human skin based on in vivo diffuse reflectance spectra. The rebuild diffuse reflectance spectra were investigated by adding melanin into different layers of the theoretical model. One of in vivo reflectance spectra from Junctional nevi and their surrounding normal skin was studied by compare the ratio between nevus and normal skin tissue in both the experimental and simulated diffuse reflectance spectra. The simulation result showed a good agreement with our clinical measurements, which indicated that our research method, including the spectral ratio method, skin optical model and modifying the melanin content in the model, could be applied in further theoretical simulation of pigmented skin lesions.

  8. Reconstructing in-vivo reflectance spectrum of pigmented skin lesion by Monte Carlo simulation

    NASA Astrophysics Data System (ADS)

    Wang, Shuang; He, Qingli; Zhao, Jianhua; Lui, Harvey; Zeng, Haishan

    2011-11-01

    In dermatology applications, diffuse reflectance spectroscopy has been extensively investigated as a promising tool for the noninvasive method to distinguish melanoma from benign pigmented skin lesion (nevus), which is concentrated with the skin chromophores like melanin and hemoglobin. We carried out a theoretical study to examine melanin distribution in human skin tissue and establish a practical optical model for further pigmented skin investigation. The theoretical simulation was using junctional nevus as an example. A multiple layer skin optical model was developed on established anatomy structures of skin, the published optical parameters of different skin layers, blood and melanin. Monte Carlo simulation was used to model the interaction between excitation light and skin tissue and rebuild the diffuse reflectance process from skin tissue. A testified methodology was adopted to determine melanin contents in human skin based on in vivo diffuse reflectance spectra. The rebuild diffuse reflectance spectra were investigated by adding melanin into different layers of the theoretical model. One of in vivo reflectance spectra from Junctional nevi and their surrounding normal skin was studied by compare the ratio between nevus and normal skin tissue in both the experimental and simulated diffuse reflectance spectra. The simulation result showed a good agreement with our clinical measurements, which indicated that our research method, including the spectral ratio method, skin optical model and modifying the melanin content in the model, could be applied in further theoretical simulation of pigmented skin lesions.

  9. Effects of a skin-massaging device on the ex-vivo expression of human dermis proteins and in-vivo facial wrinkles.

    PubMed

    Caberlotto, Elisa; Ruiz, Laetitia; Miller, Zane; Poletti, Mickael; Tadlock, Lauri

    2017-01-01

    Mechanical and geometrical cues influence cell behaviour. At the tissue level, almost all organs exhibit immediate mechanical responsiveness, in particular by increasing their stiffness in direct proportion to an applied mechanical stress. It was recently shown in cultured-cell models, in particular with fibroblasts, that the frequency of the applied stress is a fundamental stimulating parameter. However, the influence of the stimulus frequency at the tissue level has remained elusive. Using a device to deliver an oscillating torque that generates cyclic strain at different frequencies, we studied the effect(s) of mild skin massage in an ex vivo model and in vivo. Skin explants were maintained ex vivo for 10 days and massaged twice daily for one minute at various frequencies within the range of 65-85 Hz. Biopsies were analysed at D0, D5 and D10 and processed for immuno-histological staining specific to various dermal proteins. As compared to untreated skin explants, the massaging procedure clearly led to higher rates of expression, in particular for decorin, fibrillin, tropoelastin, and procollagen-1. The mechanical stimulus thus evoked an anti-aging response. Strikingly, the expression was found to depend on the stimulus frequency with maximum expression at 75Hz. We then tested whether this mechanical stimulus had an anti-aging effect in vivo. Twenty Caucasian women (aged 65-75y) applied a commercial anti-aging cream to the face and neck, followed by daily treatments using the anti-aging massage device for 8 weeks. A control group of twenty-two women, with similar ages to the first group, applied the cream alone. At W0, W4 and W8, a blinded evaluator assessed the global facial wrinkles, skin texture, lip area, cheek wrinkles, neck sagging and neck texture using a clinical grading scale. We found that combining the massaging device with a skin anti-aging formulation amplified the beneficial effects of the cream.

  10. In vivo observation of age-related structural changes of dermal collagen in human facial skin using collagen-sensitive second harmonic generation microscope equipped with 1250-nm mode-locked Cr:Forsterite laser

    NASA Astrophysics Data System (ADS)

    Yasui, Takeshi; Yonetsu, Makoto; Tanaka, Ryosuke; Tanaka, Yuji; Fukushima, Shu-ichiro; Yamashita, Toyonobu; Ogura, Yuki; Hirao, Tetsuji; Murota, Hiroyuki; Araki, Tsutomu

    2013-03-01

    In vivo visualization of human skin aging is demonstrated using a Cr:Forsterite (Cr:F) laser-based, collagen-sensitive second harmonic generation (SHG) microscope. The deep penetration into human skin, as well as the specific sensitivity to collagen molecules, achieved by this microscope enables us to clearly visualize age-related structural changes of collagen fiber in the reticular dermis. Here we investigated intrinsic aging and/or photoaging in the male facial skin. Young subjects show dense distributions of thin collagen fibers, whereas elderly subjects show coarse distributions of thick collagen fibers. Furthermore, a comparison of SHG images between young and elderly subjects with and without a recent life history of excessive sun exposure show that a combination of photoaging with intrinsic aging significantly accelerates skin aging. We also perform image analysis based on two-dimensional Fourier transformation of the SHG images and extracted an aging parameter for human skin. The in vivo collagen-sensitive SHG microscope will be a powerful tool in fields such as cosmeceutical sciences and anti-aging dermatology.

  11. Mechanism and biological relevance of blue-light (420-453 nm)-induced nonenzymatic nitric oxide generation from photolabile nitric oxide derivates in human skin in vitro and in vivo.

    PubMed

    Opländer, Christian; Deck, Annika; Volkmar, Christine M; Kirsch, Michael; Liebmann, Jörg; Born, Matthias; van Abeelen, Frank; van Faassen, Ernst E; Kröncke, Klaus-Dietrich; Windolf, Joachim; Suschek, Christoph V

    2013-12-01

    Human skin contains photolabile nitric oxide (NO) derivates such as nitrite and S-nitrosothiols, which upon UVA radiation decompose under high-output NO formation and exert NO-specific biological responses such as increased local blood flow or reduced blood pressure. To avoid the injurious effects of UVA radiation, we here investigated the mechanism and biological relevance of blue-light (420-453 nm)-induced nonenzymatic NO generation from photolabile nitric oxide derivates in human skin in vitro and in vivo. As quantified by chemiluminescence detection (CLD), at physiological pH blue light at 420 or 453 nm induced a significant NO formation from S-nitrosoalbumin and also from aqueous nitrite solutions by a to-date not entirely identified Cu(1+)-dependent mechanism. As detected by electron paramagnetic resonance spectrometry in vitro with human skin specimens, blue light irradiation significantly increased the intradermal levels of free NO. As detected by CLD in vivo in healthy volunteers, irradiation of human skin with blue light induced a significant emanation of NO from the irradiated skin area as well as a significant translocation of NO from the skin surface into the underlying tissue. In parallel, blue light irradiation caused a rapid and significant rise in local cutaneous blood flow as detected noninvasively by using micro-light-guide spectrophotometry. Irradiation of human skin with moderate doses of blue light caused a significant increase in enzyme-independent cutaneous NO formation as well as NO-dependent local biological responses, i.e., increased blood flow. The effects were attributed to blue-light-induced release of NO from cutaneous photolabile NO derivates. Thus, in contrast to UVA, blue-light-induced NO generation might be therapeutically used in the treatment of systemic and local hemodynamic disorders that are based on impaired physiological NO production or bioavailability.

  12. Terahertz spectroscopy of pigmentary skin nevi in vivo

    NASA Astrophysics Data System (ADS)

    Zaitsev, K. I.; Chernomyrdin, N. V.; Kudrin, K. G.; Reshetov, I. V.; Yurchenko, S. O.

    2015-09-01

    Pigmentary skin nevi are studied in vivo using terahertz pulsed spectroscopy. Dielectric parameters of healthy skin and dysplastic and nondysplastic nevi are reconstructed and analyzed. The fact that complex permittivities of the samples substantially differ in the terahertz spectral range can be used for early noninvasive diagnostics of dysplastic nevi, which are precursors of melanoma (the most dangerous skin cancer). A method is proposed to identify various dysplastic and nondysplastic nevi using the analysis of terahertz dielectric characteristics. It is demonstrated that terahertz pulsed spectroscopy is promising for early noninvasive diagnostics of dysplastic nevi and melanomas of the skin.

  13. Monte Carlo simulation of near infrared autofluorescence measurements of in vivo skin.

    PubMed

    Wang, Shuang; Zhao, Jianhua; Lui, Harvey; He, Qingli; Zeng, Haishan

    2011-12-02

    The autofluorescence properties of normal human skin in the near-infrared (NIR) spectral range were studied using Monte Carlo simulation. The light-tissue interactions including scattering, absorption and anisotropy propagation of the regenerated autofluorescence photons in the skin tissue were taken into account in the theoretical modeling. Skin was represented as a turbid seven-layered medium. To facilitate the simulation, ex vivo NIR autofluorescence spectra and images from different skin layers were measured from frozen skin vertical sections to define the intrinsic fluorescence properties. Monte Carlo simulation was then used to study how the intrinsic fluorescence spectra were distorted by the tissue reabsorption and scattering during in vivo measurements. We found that the reconstructed model skin spectra were in good agreement with the measured in vivo skin spectra from the same anatomical site as the ex vivo tissue sections, demonstrating the usefulness of this modeling. We also found that difference exists over the melanin fluorescent wavelength range (880-910 nm) between the simulated spectrum and the measured in vivo skin spectrum from a different anatomical site. This difference suggests that melanin contents may affect in vivo skin autofluorescence properties, which deserves further investigation.

  14. In vivo multiphoton endoscopy of endogenous skin fluorophores

    NASA Astrophysics Data System (ADS)

    Ehlers, Alexander; Schenkl, Selma; Riemann, Iris; Messerschmidt, Bernhard; Kaatz, Martin; Bückle, Rainer; König, Karsten

    2007-02-01

    Multiphoton tomography offers a painless method to examine patients under natural physiological conditions in vivo. Multiphoton excitation induces a weak autofluorescence of naturally endogenous fluorescent bio-molecules, such as flavines, NAD(P)H, metal-free porphyrines, components of lipofuscin, elastin and keratin. Additionally, collagen can be detected by second harmonic generation (SHG). Due to the nonlinearity, the effects occur only in a very tight focus, where the photon density is high enough. This leads to high axial and lateral resolution of <1μm without any need of a confocal detection and avoids out-of-focus damage. The limited depth range, given by the working distance of the focusing optics, is overcome with a gradient index-lens (GRIN-lens) based endoscope. In this work we present the first results of clinical applications in vivo of gradient-index lens endoscopes. Images of e.g. elastin and collagen (SHG) in the dermal layer of human skin are presented.

  15. In vivo skin penetration of salicylic compounds in hairless rats.

    PubMed

    Simonsen, Lene; Petersen, Mads B; Groth, Lotte

    2002-10-01

    The in vivo skin penetration of four salicylic compounds was investigated using a hairless rat model, which allowed for non-occluded, finite dose application, and free mobility of the rats throughout the test period. The model compounds were applied in equimolal concentrations of 0.4 mmol/g dimethyl isosorbide. At certain times (0.5-24 h) the rats were killed, and the amount of test compound on the skin surface, in the stratum corneum, and in the deeper viable skin layers was determined. Significant different skin concentrations were found with the following ranking: [(14)C]diethylamine salicylate>[(14)C]salicylic acid>[(14)C]salicylamide>[(14)C]butyl salicylate. In addition, the in vivo percutaneous rate of absorption was in the following order: [(14)C]butyl salicylate>[(14)C]salicylic acid> or =[(14)C]salicylamide>[(14)C]diethylamine salicylate. [(14)C]Butyl salicylate was rapidly absorbed and completely depleted from the surface 3 h post application. In comparison with [(14)C]salicylic acid, the ionic [(14)C]diethylamine salicylate had larger surface depots and penetrated the skin at a lower rate. The relatively hydrophilic [(14)C]salicylamide also had larger surface depots but much lower skin levels. For comparison, the in vitro permeation of the formulations was studied through freshly excised hairless rat skin using Franz diffusions cells, and an agreement between the techniques was found.

  16. Non-invasive in vivo determination of the carotenoids beta-carotene and lycopene concentrations in the human skin using the Raman spectroscopic method

    NASA Astrophysics Data System (ADS)

    Darvin, M. E.; Gersonde, I.; Meinke, M.; Sterry, W.; Lademann, J.

    2005-08-01

    Resonance Raman spectroscopy was used as a fast and non-invasive optical method of measuring the absolute concentrations of beta-carotene and lycopene in living human skin. Beta-carotene and lycopene have different absorption values at 488 and 514.5 nm and, consequently, the Raman lines for beta-carotene and lycopene have different scattering efficiencies at 488 and 514.5 nm excitations. These differences were used for the determination of the concentrations of beta-carotene and lycopene. Using multiline Ar+ laser excitation, clearly distinguishable carotenoid Raman spectra can be obtained which are superimposed on a large fluorescence background. The Raman signals are characterized by two prominent Stokes lines at 1160 and 1525 cm-1, which have nearly identical relative intensities. Both substances were detected simultaneously. The Raman spectra are obtained rapidly, i.e. within about 10 s, and the required laser light exposure level is well within safety standards. The disturbance of the measurements by non-homogeneous skin pigmentation was avoided by using a relatively large measuring area of 35 mm2. It was shown that beta-carotene and lycopene distribution in human skin strongly depends upon the skin region studied and drastically changed inter-individually. Skin beta-carotene and lycopene concentrations are lower in smokers than in non-smokers and higher in the vegetarian group.

  17. Increased in vivo skin penetration of quantum dots with UVR and in vitro quantum dot cytotoxicity

    NASA Astrophysics Data System (ADS)

    Mortensen, Luke; Zheng, Hong; Faulknor, Renea; De Benedetto, Anna; Beck, Lisa; DeLouise, Lisa A.

    2009-02-01

    The growing presence of quantum dots (QD) in a variety of biological, medical, and electronics applications means an increased risk of human exposure in manufacturing, research, and consumer use. However, very few studies have investigated the susceptibility of skin to penetration of QD - the most common exposure route- and the results of those that exist are conflicting. This suggests that a technique allowing determination of skin barrier status and prediction of skin permeability to QD would be of crucial interest as recent findings have provided evidence of in vitro cytotoxicity and long-term in vivo retention in the body for most QD surface chemistries. Our research focuses on barrier status of the skin (intact and with ultraviolet radiation induced barrier defect) and its impact on QD skin penetration. These model studies are particularly relevant to the common application condition of NP containing sunscreen and SPF cosmetics to UV exposed skin. Herein we present our initial efforts to develop an in vivo model of nanoparticle skin penetration using the SKH-1 hairless mouse with transepidermal water loss (TEWL) to evaluate skin barrier status and determine its ability to predict QD penetration. Our results show that ultraviolet radiation increases both TEWL and skin penetration of QD. Additionally, we demonstrate cytotoxic potential of QD to skin cells using a metastatic melanoma cell line. Our research suggests future work in specific targeting of nanoparticles, to prevent or enhance penetration. This knowledge will be used to develop powerful therapeutic agents, decreased penetration cosmetic nanoparticles, and precise skin cancer imaging modalities.

  18. Investigation of in-vivo skin autofluorescence lifetimes under long-term cw optical excitation

    SciTech Connect

    Lihachev, A; Ferulova, I; Vasiljeva, K; Spigulis, J

    2014-08-31

    The main results obtained during the last five years in the field of laser-excited in-vivo human skin photobleaching effects are presented. The main achievements and results obtained, as well as methods and experimental devices are briefly described. In addition, the impact of long-term 405-nm cw low-power laser excitation on the skin autofluorescence lifetime is experimentally investigated. (laser biophotonics)

  19. In vivo hyperspectral imaging and differentiation of skin cancer

    NASA Astrophysics Data System (ADS)

    Zherdeva, Larisa A.; Bratchenko, Ivan A.; Myakinin, Oleg O.; Moryatov, Alexander A.; Kozlov, Sergey V.; Zakharov, Valery P.

    2016-10-01

    Results of hyperspectral imaging analysis for in vivo visualization of skin neoplasms are presented. 16 melanomas, 19 basal cell carcinomas and 10 benign tumors with different stages of neoplasm growth were tested. The HSI system provide skin tissue images with 5 nm spectral resolution in the range of 450-750 nm with automatic stabilization of each frame compensating displacement of the scanning area due to spontaneous macro-movements of the patient. The integrated optical densities in 530-600 and 600-670 nm ranges are used for real-time hemoglobin and melanin distribution imaging in skin tissue. It was shown that the total accuracy of skin cancer identification exceeds 90% and 70% for differentiation of melanomas from BCC and begihn tumors. It was demonstrated the possibility for HSI classification of melanomas of different stages.

  20. In vivo activation of human immunodeficiency virus type 1 long terminal repeat by UV type A (UV-A) light plus psoralen and UV-B light in the skin of transgenic mice.

    PubMed Central

    Morrey, J D; Bourn, S M; Bunch, T D; Jackson, M K; Sidwell, R W; Barrows, L R; Daynes, R A; Rosen, C A

    1991-01-01

    UV irradiation has been shown to activate the human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR) in cell culture; however, only limited studies have been described in vivo. UV light has been categorized as UV-A (400 to 315 nm), -B (315 to 280 nm), or -C (less than 280 nm); the longer wavelengths are less harmful but more penetrative. Highly penetrative UV-A radiation constitutes the vast majority of UV sunlight reaching the earth's surface but is normally harmless. UV-B irradiation is more harmful but less prevalent than UV-A. In this report, the HIV-1 LTR-luciferase gene in the skin of transgenic mice was markedly activated when exposed to UV-B irradiation. The LTR in the skin of transgenic mice pretreated topically with a photosensitizing agent (psoralen) was also activated to similar levels when exposed to UV-A light. A 2-h exposure to sunlight activated the LTR in skin treated with psoralen, whereas the LTR in skin not treated with psoralen was activated after 7 h of sunlight exposure. The HIV-1 LTR-beta-galactosidase reporter gene was preferentially activated by UV-B irradiation in a small population of epidermal cells. The transgenic mouse models carrying HIV-1 LTR-luciferase and LTR-beta-galactosidase reporter genes have been used to demonstrate the in vivo UV-induced activation of the LTR and might be used to evaluate other environmental factors or pharmacologic substances that might potentially activate the HIV-1 LTR in vivo. Images PMID:1908029

  1. In vivo spectroscopy of healthy skin and pathology in terahertz frequency range

    NASA Astrophysics Data System (ADS)

    Zaytsev, Kirill I.; Kudrin, Konstantin G.; Reshetov, Igor V.; Gavdush, Arseniy A.; Chernomyrdin, Nikita V.; Karasik, Valeriy E.; Yurchenko, Stanislav O.

    2015-01-01

    Biomedical applications of terahertz (THz) technology and, in particular, THz pulsed spectroscopy have attracted considerable interest in the scientific community. A lot of papers have been dedicated to studying the ability for human disease diagnosis, including the diagnosis of human skin cancers. In this paper we have studied the THz material parameters and THz dielectric properties of human skin and pathology in vivo, and THz pulsed spectroscopy has been utilized for this purpose. We have found a contrast between material parameters of basal cell carcinoma and healthy skin, and we have also compared the THz material parameters of dysplastic and non-dysplastic pigmentary nevi in order to study the ability for early melanoma diagnosis. Significant differences between the THz material parameters of healthy skin and pathology have been detected, thus, THz pulsed spectroscopy promises to be become an effective tool for non-invasive diagnosis of skin neoplasms.

  2. Luminescence monitoring of particle delivery into rat skin in vivo

    NASA Astrophysics Data System (ADS)

    Volkova, E. K.; Yanina, I. Y.; Genina, E. A.; Dolotov, L. E.; Bashkatov, A. N.; Genin, V. D.; Konyukhova, J. G.; Popov, A. P.; Kozintseva, M. D.; Speranskaya, E.; Lomova, M.; Terentyuk, G. S.; Bucharskaya, A. B.; Navolokin, N. A.; Goryacheva, I. Y.; Kochubey, V. I.; Gorin, D. A.; Tuchin, V. V.; Sukhorukov, G. B.

    2015-07-01

    Delivery of upconversion microparticles [Y2O3:Yb, Er] and quantum dots (CuInS2/ZnS coated with PEG-based amphiphilic polymer) into rat skin using the fractional laser microablation has been studied in vivo. Luminescence spectroscopy, optical coherence tomography, confocal microscopy, and histochemical analysis were used for visualization of nanoparticles in microchannels. Results have shown that the upconversion microparticles are detected more efficiently in comparison with the quantum dots. The fluorescence intensity of the inserted upconversion microparticles is higher, when the Omnipaque™ was applied as a skin optical clearing agent. The fluorescent images of upconversion nanoparticle distribution indicate the advantage of particle delivery into skin by ultrasound.

  3. The ubiquitous cellular transcriptional factor USF targets the varicella-zoster virus open reading frame 10 promoter and determines virulence in human skin xenografts in SCIDhu mice in vivo.

    PubMed

    Che, Xibing; Berarducci, Barbara; Sommer, Marvin; Ruyechan, William T; Arvin, Ann M

    2007-04-01

    Varicella-zoster virus (VZV) open reading frame 10 (ORF10) is a determinant of virulence in SCIDhu skin xenografts but not in human T cells in vivo. In this analysis of the regulation of ORF10 transcription, we have identified four ORF10-related transcripts, including a major 1.3-kb RNA spanning ORF10 only and three other read-through transcripts. Rapid-amplification-of-cDNA-ends experiments indicated that the 1.3-kb transcript of ORF10 has single initiation and termination sites. In transient expression assays, the ORF10 promoter was strongly stimulated by the major VZV transactivator, IE62. Deletion analyses revealed approximate boundaries for the full ORF10 promoter activity between -75 and -45 and between +5 and -8, relative to the ORF10 transcription start site. The recombinant virus POKA10-Deltapro, with the ORF10 promoter deletion, blocked transcription of ORF10 and also of ORF9A and ORF9 mRNAs, whereas expression of read-through ORF9A/9/10 and ORF9/10 transcripts was increased, compensating for the loss of the monocistronic mRNAs. The cellular factor USF bound specifically to its consensus site within the ORF10 promoter and was required for IE62 transactivation, whereas disrupting the predicted TATA boxes or Oct-1 binding elements had no effect. The USF binding site was disrupted in the recombinant virus, POKA10-proDeltaUSF, and no ORF10 protein was produced. Both ORF10 promoter mutants reduced VZV replication in SCIDhu skin xenografts. These observations provided further evidence of the contribution of the ORF10 protein to VZV pathogenesis in skin and demonstrated that VZV depends upon the cellular transcriptional factor USF to support its virulence in human skin in vivo.

  4. Motion-artifact-robust, polarization-resolved second-harmonic-generation microscopy based on rapid polarization switching with electro-optic Pockells cell and its application to in vivo visualization of collagen fiber orientation in human facial skin.

    PubMed

    Tanaka, Yuji; Hase, Eiji; Fukushima, Shuichiro; Ogura, Yuki; Yamashita, Toyonobu; Hirao, Tetsuji; Araki, Tsutomu; Yasui, Takeshi

    2014-04-01

    Polarization-resolved second-harmonic-generation (PR-SHG) microscopy is a powerful tool for investigating collagen fiber orientation quantitatively with low invasiveness. However, the waiting time for the mechanical polarization rotation makes it too sensitive to motion artifacts and hence has hampered its use in various applications in vivo. In the work described in this article, we constructed a motion-artifact-robust, PR-SHG microscope based on rapid polarization switching at every pixel with an electro-optic Pockells cell (PC) in synchronization with step-wise raster scanning of the focus spot and alternate data acquisition of a vertical-polarization-resolved SHG signal and a horizontal-polarization-resolved one. The constructed PC-based PR-SHG microscope enabled us to visualize orientation mapping of dermal collagen fiber in human facial skin in vivo without the influence of motion artifacts. Furthermore, it implied the location and/or age dependence of the collagen fiber orientation in human facial skin. The robustness to motion artifacts in the collagen orientation measurement will expand the application scope of SHG microscopy in dermatology and collagen-related fields.

  5. Photobleaching effects on in vivo skin autofluorescence lifetime

    NASA Astrophysics Data System (ADS)

    Ferulova, Inesa; Lihachev, Alexey; Spigulis, Janis

    2015-05-01

    The autofluorescence lifetime of healthy human skin was measured using excitation provided by a picosecond diode laser operating at a wavelength of 405 nm and with fluorescence emission collected at 475 and 560 nm. In addition, spectral and temporal responses of healthy human skin and intradermal nevus in the spectral range 460 to 610 nm were studied before and after photobleaching. A decrease in the autofluorescences lifetimes changes was observed after photobleaching of human skin. A three-exponential model was used to fit the signals, and under this model, the most significant photoinduced changes were observed for the slowest lifetime component in healthy skin at the spectral range 520 to 610 nm and intradermal nevus at the spectral range 460 to 610 nm.

  6. A Guide to Studying Human Hair Follicle Cycling In Vivo.

    PubMed

    Oh, Ji Won; Kloepper, Jennifer; Langan, Ewan A; Kim, Yongsoo; Yeo, Joongyeub; Kim, Min Ji; Hsi, Tsai-Ching; Rose, Christian; Yoon, Ghil Suk; Lee, Seok-Jong; Seykora, John; Kim, Jung Chul; Sung, Young Kwan; Kim, Moonkyu; Paus, Ralf; Plikus, Maksim V

    2016-01-01

    Hair follicles (HFs) undergo lifelong cyclical transformations, progressing through stages of rapid growth (anagen), regression (catagen), and relative "quiescence" (telogen). Given that HF cycling abnormalities underlie many human hair growth disorders, the accurate classification of individual cycle stages within skin biopsies is clinically important and essential for hair research. For preclinical human hair research purposes, human scalp skin can be xenografted onto immunocompromised mice to study human HF cycling and manipulate long-lasting anagen in vivo. Although available for mice, a comprehensive guide on how to recognize different human hair cycle stages in vivo is lacking. In this article, we present such a guide, which uses objective, well-defined, and reproducible criteria, and integrates simple morphological indicators with advanced, (immuno)-histochemical markers. This guide also characterizes human HF cycling in xenografts and highlights the utility of this model for in vivo hair research. Detailed schematic drawings and representative micrographs provide examples of how best to identify human HF stages, even in suboptimally sectioned tissue, and practical recommendations are given for designing human-on-mouse hair cycle experiments. Thus, this guide seeks to offer a benchmark for human hair cycle stage classification, for both hair research experts and newcomers to the field.

  7. A guide to studying human hair follicle cycling in vivo

    PubMed Central

    Oh, Ji Won; Kloepper, Jennifer; Langan, Ewan A.; Kim, Yongsoo; Yeo, Joongyeub; Kim, Min Ji; Hsi, Tsai-Ching; Rose, Christian; Yoon, Ghil Suk; Lee, Seok-Jong; Seykora, John; Kim, Jung Chul; Sung, Young Kwan

    2015-01-01

    Hair follicles (HFs) undergo life-long cyclical transformations, progressing through stages of rapid growth (anagen), regression (catagen), and relative “quiescence” (telogen). Since HF cycling abnormalities underlie many human hair growth disorders, the accurate classification of individual cycle stages within skin biopsies is clinically important and essential for hair research. For preclinical human hair research purposes, human scalp skin can be xenografted onto immunocompromised mice to study human HF cycling and manipulate long-lasting anagen in vivo. While available for mice, a comprehensive guide on how to recognize different human hair cycle stages in vivo is lacking. Here, we present such a guide, which uses objective, well-defined, and reproducible criteria and integrates simple morphological indicators with advanced, (immuno)-histochemical markers. This guide also characterizes human HF cycling in xenografts and highlights the utility of this model for in vivo hair research. Detailed schematic drawings and representative micrographs provide examples of how best to identify human HF stages, even in sub-optimally sectioned tissue, and practical recommendations are given for designing human-on-mouse hair cycle experiments. Thus, this guide seeks to offer a benchmark for human hair cycle stage classification, for both hair research experts and newcomers to the field. PMID:26763421

  8. In vivo iontophoretic delivery of salmon calcitonin across microporated skin.

    PubMed

    Vemulapalli, Viswatej; Bai, Yun; Kalluri, Haripriya; Herwadkar, Anushree; Kim, Hyun; Davis, Shawn P; Friden, Phil M; Banga, Ajay K

    2012-08-01

    The purpose of this study was to determine the effect of microneedle (MN) technology and its combination with iontophoresis (ITP) on the in vivo transdermal delivery of salmon calcitonin (sCT). Maltose MNs (500 µm) were used to porate skin prior to application of the drug, with or without ITP. Micropores created by maltose MNs were characterized by histological sectioning and calcein imaging studies, which indicated uniformity of the created micropores. In vivo studies were performed in hairless rats to assess the degree of enhancement achieved by ITP (0.2 mA/cm² for 1 h), MNs (81 MNs), and their combination. In vivo studies indicate a serum maximal concentration of 0.61 ± 0.42 ng/mL, 1.79 ± 0.72 ng/mL, and 5.51 ± 0.32 ng/mL for ITP, MNs, and combination treatment, respectively. MN treatment alone increased serum concentration 2.5-fold and the combination treatment increased the concentration ninefold as compared with iontophoretic treatment alone. Combination treatment of ITP and MNs resulted in the highest delivery of sCT and therapeutic levels were achieved within 5 min of administration.

  9. Complex spectral OCT in human eye imaging in vivo

    NASA Astrophysics Data System (ADS)

    Targowski, Piotr; Wojtkowski, Maciej; Kowalczyk, Andrzej; Bajraszewski, Tomasz; Szkulmowski, Maciej; Gorczyńska, Iwona

    2004-01-01

    Complex spectral optical coherence tomography in comparison to spectral optical coherence tomography produces images free of parasitic terms with extended measurement range. This technique requires stability of the object during at least three consecutive measurements. In this paper we present how to improve this technique to make measurements less sensitive to involuntary eye movements. The first images of human skin and anterior chamber of the eye in vivo based on complex spectral optical coherence tomography are presented.

  10. In vivo terahertz imaging of rat skin burns

    NASA Astrophysics Data System (ADS)

    Tewari, Priyamvada; Kealey, Colin P.; Bennett, David B.; Bajwa, Neha; Barnett, Kelli S.; Singh, Rahul S.; Culjat, Martin O.; Stojadinovic, Alexander; Grundfest, Warren S.; Taylor, Zachary D.

    2012-04-01

    A reflective, pulsed terahertz (THz) imaging system was used to acquire high-resolution (d10-90/ λ~1.925) images of deep, partial thickness burns in a live rat. The rat's abdomen was burned with a brass brand heated to ~220°C and pressed against the skin with contact pressure for ~10 sec. The burn injury was imaged beneath a Mylar window every 15 to 30 min for up to 7 h. Initial images display an increase in local water concentration of the burned skin as evidenced by a marked increase in THz reflectivity, and this likely correlates to the post-injury inflammatory response. After ~1 h the area of increased reflectivity consolidated to the region of skin that had direct contact with the brand. Additionally, a low reflecting ring of tissue could be observed surrounding the highly reflective burned tissue. We hypothesize that these regions of increased and decreased reflectivity correlate to the zones of coagulation and stasis that are the classic foundation of burn wound histopathology. While further investigations are necessary to confirm this hypothesis, if true, it likely represents the first in vivo THz images of these pathologic zones and may represent a significant step forward in clinical application of THz technology.

  11. Simulating the three-dimensional deformation of in vivo facial skin.

    PubMed

    Flynn, Cormac; Taberner, Andrew J; Nielsen, Poul M F; Fels, Sidney

    2013-12-01

    Characterising the mechanical properties of human facial skin is a challenging but important endeavour with applications in biomedicine, surgery simulation, forensics, and animation. Many existing computer models of the face are not based on in vivo facial skin deformation data but rather on experiments using in vitro facial skin or other soft tissues. The facial skin of five volunteers was subjected to a rich set of deformations using a micro-robotic device. The force-displacement response was recorded for each deformation. All volunteers' facial skin exhibited a non-linear, anisotropic, and viscoelastic force-displacement response. We propose a finite element model that simulated the experimental deformations with error-of-fits ranging from 11% to 23%. The skin was represented by an Ogden strain energy function and a quasi-linear viscoelastic law. From non-linear optimisation procedures, we determined material parameters and in vivo pre-stresses for the central cheek area of five volunteers and five other facial points on one volunteer. Pre-stresses ranged from 15.9kPa to 89.4kPa.

  12. In vivo multiphoton tomography in skin aging studies

    NASA Astrophysics Data System (ADS)

    König, Karsten; Bückle, Rainer; Weinigel, Martin; Köhler, Johannes; Elsner, Peter; Kaatz, Martin

    2009-02-01

    High-resolution clinical multiphoton tomography based on the femtosecond laser system DermaInspect has been performed on hundreds of patients and volunteers in Australia, Asia, and Europe. The system enables the in vivo detection of the elastin and the collagen network as well as the imaging of melanin clusters in aging spots. The epidermis-dermis junction can be detected with submicron resolution. One major applications of this novel HighTech imaging tool is the determination of the skin aging index SAAID as well as the study of the effects of anti-aging products. In particular, the stimulated biosynthesis of collagen can be investigated over long periods of time. The system with its sub-500 nm lateral resolution is able to image age-related modifications of the extracellular matrix on the level of a single elastin fiber.

  13. Archaea on Human Skin

    PubMed Central

    Probst, Alexander J.; Auerbach, Anna K.; Moissl-Eichinger, Christine

    2013-01-01

    The recent era of exploring the human microbiome has provided valuable information on microbial inhabitants, beneficials and pathogens. Screening efforts based on DNA sequencing identified thousands of bacterial lineages associated with human skin but provided only incomplete and crude information on Archaea. Here, we report for the first time the quantification and visualization of Archaea from human skin. Based on 16 S rRNA gene copies Archaea comprised up to 4.2% of the prokaryotic skin microbiome. Most of the gene signatures analyzed belonged to the Thaumarchaeota, a group of Archaea we also found in hospitals and clean room facilities. The metabolic potential for ammonia oxidation of the skin-associated Archaea was supported by the successful detection of thaumarchaeal amoA genes in human skin samples. However, the activity and possible interaction with human epithelial cells of these associated Archaea remains an open question. Nevertheless, in this study we provide evidence that Archaea are part of the human skin microbiome and discuss their potential for ammonia turnover on human skin. PMID:23776475

  14. Archaea on human skin.

    PubMed

    Probst, Alexander J; Auerbach, Anna K; Moissl-Eichinger, Christine

    2013-01-01

    The recent era of exploring the human microbiome has provided valuable information on microbial inhabitants, beneficials and pathogens. Screening efforts based on DNA sequencing identified thousands of bacterial lineages associated with human skin but provided only incomplete and crude information on Archaea. Here, we report for the first time the quantification and visualization of Archaea from human skin. Based on 16 S rRNA gene copies Archaea comprised up to 4.2% of the prokaryotic skin microbiome. Most of the gene signatures analyzed belonged to the Thaumarchaeota, a group of Archaea we also found in hospitals and clean room facilities. The metabolic potential for ammonia oxidation of the skin-associated Archaea was supported by the successful detection of thaumarchaeal amoA genes in human skin samples. However, the activity and possible interaction with human epithelial cells of these associated Archaea remains an open question. Nevertheless, in this study we provide evidence that Archaea are part of the human skin microbiome and discuss their potential for ammonia turnover on human skin.

  15. Establishment of a murine epidermal cell line suitable for in vitro and in vivo skin modelling

    PubMed Central

    2011-01-01

    Background Skin diseases are a major health problem. Some of the most severe conditions involve genetic disorders, including cancer. Several of these human diseases have been modelled in genetically modified mice, thus becoming a highly valuable preclinical tool for the treatment of these pathologies. However, development of three-dimensional models of skin using keratinocytes from normal and/or genetically modified mice has been hindered by the difficulty to subculture murine epidermal keratinocytes. Methods We have generated a murine epidermal cell line by serially passaging keratinocytes isolated from the back skin of adult mice. We have termed this cell line COCA. Cell culture is done in fully defined media and does not require feeder cells or any other coating methods. Results COCA retained its capacity to differentiate and stratify in response to increased calcium concentration in the cell culture medium for more than 75 passages. These cells, including late passage, can form epidermis-like structures in three-dimensional in vitro models with a well-preserved pattern of proliferation and differentiation. Furthermore, these cells form epidermis in grafting assays in vivo, and do not develop tumorigenic ability. Conclusions We propose that COCA constitutes a good experimental system for in vitro and in vivo skin modelling. Also, cell lines from genetically modified mice of interest in skin biology could be established using the method we have developed. COCA keratinocytes would be a suitable control, within a similar background, when studying the biological implications of these alterations. PMID:21510892

  16. Ultrasound imaging system for measuring stiffness variation in the fingerpad skin in vivo

    NASA Astrophysics Data System (ADS)

    Wu, Wan-Chen; Raju, Balasundar I.; Srinivasan, Mandayam A.

    2005-04-01

    An elasticity imaging system was developed for measuring the stiffness variation at different depths of the human fingerpad skin in vivo. In this system, ultrasonic backscatter microscopy (UBM) with a single high frequency (28MHz) transducer was employed to obtain data on tissue heterogeneity at high axial resolution (~25 mm). The dorsal side of the finger was fixed on a manually controlled vertical stage and an acrylic indentor was applied to the fingerpad. A slit cut vertically through the indentor at the center and a piece of transparency sheet attached to the bottom allowed most of the ultrasound power to pass though while maintaining a flat surface in contact with the skin. With the assumption that the skin can be modeled as a semi-infinite layered structure, only data from a single A-line was obtained for strain analysis. The data at continuous indentation steps were cross-correlated to calculate the displacement at different spots along the depth. The de-correlation at certain regions was resolved by removing the data points with lower correlation coefficients, and curve fitting was applied to overcome the lack of resolution due to sampling. The fingerpads of 10 human subjects were tested in vivo and a gelatin phantom was made and tested for comparison. The results showed that even though some data were degraded due to the hypoechoic nature of the subcutaneous fat, the axial strain profile through the skin thickness (up to 3mm in depth) could be extracted as a measure of the stiffness variation.

  17. In vivo terahertz pulsed spectroscopy of dysplastic and non-dysplastic skin nevi

    NASA Astrophysics Data System (ADS)

    Zaytsev, Kirill I.; Chernomyrdin, Nikita V.; Kudrin, Konstantin G.; Gavdush, Arseniy A.; Nosov, Pavel A.; Yurchenko, Stanislav O.; Reshetov, Igor V.

    2016-08-01

    The results of the in vivo terahertz (THz) pulsed spectroscopy (TPS) of pigmentary skin nevi are reported. Observed THz dielectric permittivity of healthy skin and dysplastic and non-dysplastic skin nevi exhibits significant contrast in THz frequency range. Dysplastic skin nevus is a precursor of melanoma, which is reportedly the most dangerous cancer of the skin. Therefore, the THz dielectric spectroscopy is potentially an effective tool for non-invasive early diagnosis of melanomas of the skin.

  18. Glucocorticoids enhance the in vivo migratory response of human monocytes.

    PubMed

    Yeager, Mark P; Pioli, Patricia A; Collins, Jane; Barr, Fiona; Metzler, Sara; Sites, Brian D; Guyre, Paul M

    2016-05-01

    Glucocorticoids (GCs) are best known for their potent anti-inflammatory effects. However, an emerging model for glucocorticoid (GC) regulation of in vivo inflammation also includes a delayed, preparatory effect that manifests as enhanced inflammation following exposure to an inflammatory stimulus. When GCs are transiently elevated in vivo following exposure to a stressful event, this model proposes that a subsequent period of increased inflammatory responsiveness is adaptive because it enhances resistance to a subsequent stressor. In the present study, we examined the migratory response of human monocytes/macrophages following transient in vivo exposure to stress-associated concentrations of cortisol. Participants were administered cortisol for 6h to elevate in vivo cortisol levels to approximate those observed during major systemic stress. Monocytes in peripheral blood and macrophages in sterile inflammatory tissue (skin blisters) were studied before and after exposure to cortisol or placebo. We found that exposure to cortisol induced transient upregulation of monocyte mRNA for CCR2, the receptor for monocyte chemotactic protein-1 (MCP-1/CCL2) as well as for the chemokine receptor CX3CR1. At the same time, mRNA for the transcription factor IκBα was decreased. Monocyte surface expression of CCR2 but not CX3CR1 increased in the first 24h after cortisol exposure. Transient exposure to cortisol also led to an increased number of macrophages and neutrophils in fluid derived from a sterile inflammatory site in vivo. These findings suggest that the delayed, pro-inflammatory effects of cortisol on the human inflammatory responses may include enhanced localization of effector cells at sites of in vivo inflammation.

  19. In vivo assessment of the structure of skin microcirculation by reflectance confocal-laser-scanning microscopy

    NASA Astrophysics Data System (ADS)

    Sugata, Keiichi; Osanai, Osamu; Kawada, Hiromitsu

    2012-02-01

    One of the major roles of the skin microcirculation is to supply oxygen and nutrition to the surrounding tissue. Regardless of the close relationship between the microcirculation and the surrounding tissue, there are few non-invasive methods that can evaluate both the microcirculation and its surrounding tissue at the same site. We visualized microcapillary plexus structures in human skin using in vivo reflectance confocal-laser-scanning microscopy (CLSM), Vivascope 3000® (Lucid Inc., USA) and Image J software (National Institutes of Health, USA) for video image processing. CLSM is a non-invasive technique that can visualize the internal structure of the skin at the cellular level. In addition to internal morphological information such as the extracellular matrix, our method reveals capillary structures up to the depth of the subpapillary plexus at the same site without the need for additional optical systems. Video images at specific depths of the inner forearm skin were recorded. By creating frame-to-frame difference images from the video images using off-line video image processing, we obtained images that emphasize the brightness depending on changes of intensity coming from the movement of blood cells. Merging images from different depths of the skin elucidates the 3-dimensional fine line-structure of the microcirculation. Overall our results show the feasibility of a non-invasive, high-resolution imaging technique to characterize the skin microcirculation and the surrounding tissue.

  20. A finite element model of the face including an orthotropic skin model under in vivo tension.

    PubMed

    Flynn, Cormac; Stavness, Ian; Lloyd, John; Fels, Sidney

    2015-01-01

    Computer models of the human face have the potential to be used as powerful tools in surgery simulation and animation development applications. While existing models accurately represent various anatomical features of the face, the representation of the skin and soft tissues is very simplified. A computer model of the face is proposed in which the skin is represented by an orthotropic hyperelastic constitutive model. The in vivo tension inherent in skin is also represented in the model. The model was tested by simulating several facial expressions by activating appropriate orofacial and jaw muscles. Previous experiments calculated the change in orientation of the long axis of elliptical wounds on patients' faces for wide opening of the mouth and an open-mouth smile (both 30(o)). These results were compared with the average change of maximum principal stress direction in the skin calculated in the face model for wide opening of the mouth (18(o)) and an open-mouth smile (25(o)). The displacements of landmarks on the face for four facial expressions were compared with experimental measurements in the literature. The corner of the mouth in the model experienced the largest displacement for each facial expression (∼11-14 mm). The simulated landmark displacements were within a standard deviation of the measured displacements. Increasing the skin stiffness and skin tension generally resulted in a reduction in landmark displacements upon facial expression.

  1. Human tendon behaviour and adaptation, in vivo

    PubMed Central

    Magnusson, S Peter; Narici, Marco V; Maganaris, Constantinos N; Kjaer, Michael

    2008-01-01

    Tendon properties contribute to the complex interaction of the central nervous system, muscle–tendon unit and bony structures to produce joint movement. Until recently limited information on human tendon behaviour in vivo was available; however, novel methodological advancements have enabled new insights to be gained in this area. The present review summarizes the progress made with respect to human tendon and aponeurosis function in vivo, and how tendons adapt to ageing, loading and unloading conditions. During low tensile loading or with passive lengthening not only the muscle is elongated, but also the tendon undergoes significant length changes, which may have implications for reflex responses. During active loading, the length change of the tendon far exceeds that of the aponeurosis, indicating that the aponeurosis may more effectively transfer force onto the tendon, which lengthens and stores elastic energy subsequently released during unloading, in a spring-like manner. In fact, data recently obtained in vivo confirm that, during walking, the human Achilles tendon provides elastic strain energy that can decrease the energy cost of locomotion. Also, new experimental evidence shows that, contrary to earlier beliefs, the metabolic activity in human tendon is remarkably high and this affords the tendon the ability to adapt to changing demands. With ageing and disuse there is a reduction in tendon stiffness, which can be mitigated with resistance exercises. Such adaptations seem advantageous for maintaining movement rapidity, reducing tendon stress and risk of injury, and possibly, for enabling muscles to operate closer to the optimum region of the length–tension relationship. PMID:17855761

  2. Chromophores in human skin

    NASA Astrophysics Data System (ADS)

    Young, Antony R.

    1997-05-01

    Human skin, especially the epidermis, contains several major solar ultraviolet-radiation- (UVR-) absorbing endogenous chromophores including DNA, urocanic acid, amino acids, melanins and their precursors and metabolites. The lack of solubility of melanins prevents their absorption spectra being defined by routine techniques. Indirect spectroscopic methods show that their spectral properties depend on the stimulus for melanogenesis. The photochemical consequences of UVR absorption by some epidermal chromophores are relatively well understood whereas we lack a detailed understanding of the consequent photobiological and clinical responses. Skin action spectroscopy is not a reliable way of relating a photobiological outcome to a specific chromophore but is important for UVR hazard assessment. Exogenous chromophores may be administered to the skin in combination with UVR exposure for therapeutic benefit, or as sunscreens for the prevention of sunburn and possibly skin cancer.

  3. Exploring Valrubicin's Effect on Propionibacterium Acnes-Induced Skin Inflammation in Vitro and in Vivo

    PubMed Central

    Rottboell, Louise; de Foenss, Sarah; Thomsen, Kenneth; Christiansen, Helle; Andersen, Stine M.; Dam, Tomas N.; Rosada, Cecilia

    2015-01-01

    Acne is a common skin disease involving colonization with Propionibacterium acnes (P. acnes), hyperproliferation of the follicular epithelium and inflammatory events. Valrubicin is a second-generation anthracycline, non-toxic upon contact, and available in a topical formulation. Valrubicin’s predecessor doxorubicin possesses antibacterial effects and previously we demonstrated that valrubicin inhibits keratinocyte proliferation and skin inflammation suggesting beneficial topical treatment of acne with valrubicin. This study aims to investigate valrubicin’s possible use in acne treatment by testing valrubicin’s antibacterial effects against P. acnes and P. acnes-induced skin inflammation in vitro and in vivo. Valrubicin was demonstrated not to possess antibacterial effects against P. acnes. Additionally, valrubicin was demonstrated not to reduce mRNA and protein expression levels of the inflammatory markers interleukin (IL)-1β, IL-8, and tumor necrosis factor (TNF)-α in vitro in human keratinocytes co-cultured with P. acnes. Moreover, in vivo, valrubicin, applied both topically and intra-dermally, was not able to reduce signs of inflammation in mouse ears intra-dermally injected with P. acnes. Taken together, this study does not support beneficial antibacterial and anti inflammatory effects of topical valrubicin treatment of acne. PMID:26734122

  4. In vivo monitoring of external pressure induced hemodynamics in skin tissue using optical coherence tomography angiography

    NASA Astrophysics Data System (ADS)

    Choi, Woo June; Wang, Hequn; Wang, Ruikang K.

    2015-03-01

    Characterization of the relationship between external pressure and blood flow is important in the examination of pressure-induced disturbance in tissue microcirculation. Optical coherence tomography (OCT) angiography is a promising imaging technique, capable of providing the noninvasive extraction of functional vessels within the skin tissue with capillary-scale resolution. Here, we present a feasibility study of OCT angiography to monitor effect of external pressures on blood perfusion in human skin tissue in vivo. Graded external pressure is loaded normal to the surface of the nailfold tissue of a healthy human. The incremental loading is applied step by step and then followed by an immediate release. Concurrent OCT imaging of the nailfold is performed during the pre/post loading. Blood perfusion images including baseline (at pre-loading) and corresponding tissue strain maps are calculated from 3D OCT dataset obtained at the different applied pressures, allowing visualization of capillary perfusion events at stressed nailfold tissue. The results indicate that the perfusion progressively decreases with the constant increase of tissue strain. Reactive hyperemia is occurred right after the removal of the pressure corresponding to quick drop of the increased strain. The perfusion is returned to the baseline level after a few minutes. These findings suggest that OCT microangiography may have great potential for quantitatively assessing tissue microcirculation in the locally pressed tissue in vivo.

  5. Free water content and monitoring of healing processes of skin burns studied by microwave dielectric spectroscopy in vivo.

    PubMed

    Hayashi, Yoshihito; Miura, Nobuhiro; Shinyashiki, Naoki; Yagihara, Shin

    2005-02-21

    We have investigated the dielectric properties of human skin in vivo at frequencies up to 10 GHz using a time-domain reflectometry method with open-ended coaxial probes. Since gamma-dispersion results from the reorientation of free water molecules, the free water content of skin is quantitatively determined by dielectric measurements. The free water content of finger skin increased by about 10% after soaking in 37 degrees C water for 30 min, and it systematically decreased again through the drying process, as expected. Thus this analytical method has been applied to the study of skin burns. The free water content of burned human cheek skin due to hydrofluoric acid was significantly lower than that of normal skin, and the burned skin recovered through the healing process. In the case of a human hand skin burn due to heat, although the free water content was almost the same as that of normal skin at the beginning, it decreased during the healing process for the first 10 days, then began to increase. Although the number of test subjects was one for each experiment, it was shown that free water content is a good indicator for evaluating skin health and can be well monitored by dielectric spectroscopy.

  6. Free water content and monitoring of healing processes of skin burns studied by microwave dielectric spectroscopy in vivo

    NASA Astrophysics Data System (ADS)

    Hayashi, Yoshihito; Miura, Nobuhiro; Shinyashiki, Naoki; Yagihara, Shin

    2005-02-01

    We have investigated the dielectric properties of human skin in vivo at frequencies up to 10 GHz using a time-domain reflectometry method with open-ended coaxial probes. Since γ-dispersion results from the reorientation of free water molecules, the free water content of skin is quantitatively determined by dielectric measurements. The free water content of finger skin increased by about 10% after soaking in 37 °C water for 30 min, and it systematically decreased again through the drying process, as expected. Thus this analytical method has been applied to the study of skin burns. The free water content of burned human cheek skin due to hydrofluoric acid was significantly lower than that of normal skin, and the burned skin recovered through the healing process. In the case of a human hand skin burn due to heat, although the free water content was almost the same as that of normal skin at the beginning, it decreased during the healing process for the first 10 days, then began to increase. Although the number of test subjects was one for each experiment, it was shown that free water content is a good indicator for evaluating skin health and can be well monitored by dielectric spectroscopy.

  7. Optical clearing of skin under action of glycerol: Ex vivo and in vivo investigations

    NASA Astrophysics Data System (ADS)

    Genina, E. A.; Bashkatov, A. N.; Sinichkin, Yu. P.; Tuchin, V. V.

    2010-08-01

    The behavior of optical parameters of the skin of a laboratory rat under the action of an aqueous solution of glycerol is studied ex vivo and in vivo. It is found that the collimated transmission coefficient of ex vivo skin samples increases by a factor of 20-40-fold depending on the wavelength in the studied spectral range, and the diffuse reflection coefficient of skin in vivo decreases on the average by 16%. The results presented can be useful for many methods of laser therapy and optical diagnostics of skin diseases and localization of subcutaneous neoplasms.

  8. Clinical applicability of in vivo fluorescence confocal microscopy for noninvasive diagnosis and therapeutic monitoring of nonmelanoma skin cancer.

    PubMed

    Astner, Susanne; Dietterle, Susanne; Otberg, Nina; Röwert-Huber, Hans-Joachim; Stockfleth, Eggert; Lademann, Jürgen

    2008-01-01

    Excisional biopsies and routine histology remains the gold standard for the histomorphologic evaluation of normal and diseased skin. However, there is increasing interest in the development of noninvasive optical technologies for evaluation, diagnosis, and monitoring of skin disease in vivo. Fluorescent confocal microscopy is an innovative optical technology that has previously been used for morphologic evaluation of live human tissue. We evaluate the clinical applicability of a fluorescent confocal laser scanning microscope (FLSM) for a systematic evaluation of normal and diseased skin in vivo and in correlation with routine histology. A total of 40 patients were recruited to participate in the study. Skin sites of 10 participants with no prior history of skin disease served as controls and to evaluate topographic variations of normal skin in vivo. Thirty patients with a suspected diagnosis of nonmelanoma skin cancer were evaluated, whereby FLSM features of actinic keratoses (AK) and basal cell carcinoma (BCC) were recorded in an observational analysis. Selected BCCs were monitored for their skin response to topical therapy using Imiquimod as an immune-response modifier. A commercially available fluorescence microscope (OptiScan Ltd., Melbourne, Australia) was used to carry out all FLSM evaluations. Common FLSM features to AK and BCC included nuclear pleomorphism at the level of the granular and spinous layer and increased vascularity in the superficial dermal compartment. Even though the presence of superficial disruption and mere atypia of epidermal keratinocytes was more indicative of AK, the nesting of atypical basal cells, increased blood vessel tortuosity, and nuclear polarization were more typical for BCC. All diagnoses were confirmed by histology. FLSM allowed a monitoring of the local immune response following therapy with Imiquimod and demonstrated a continuous normalization of diseased skin on repeated evaluations over time. This study illustrates

  9. In vivo skin dose measurement in breast conformal radiotherapy

    PubMed Central

    Soleymanifard, Shokouhozaman; Noghreiyan, Atefeh Vejdani; Ghorbani, Mahdi; Jamali, Farideh; Davenport, David

    2016-01-01

    Aim of the study Accurate skin dose assessment is necessary during breast radiotherapy to assure that the skin dose is below the tolerance level and is sufficient to prevent tumour recurrence. The aim of the current study is to measure the skin dose and to evaluate the geometrical/anatomical parameters that affect it. Material and methods Forty patients were simulated by TIGRT treatment planning system and treated with two tangential fields of 6 MV photon beam. Wedge filters were used to homogenise dose distribution for 11 patients. Skin dose was measured by thermoluminescent dosimeters (TLD-100) and the effects of beam incident angle, thickness of irradiated region, and beam entry separation on the skin dose were analysed. Results Average skin dose in treatment course of 50 Gy to the clinical target volume (CTV) was 36.65 Gy. The corresponding dose values for patients who were treated with and without wedge filter were 35.65 and 37.20 Gy, respectively. It was determined that the beam angle affected the average skin dose while the thickness of the irradiated region and the beam entry separation did not affect dose. Since the skin dose measured in this study was lower than the amount required to prevent tumour recurrence, application of bolus material in part of the treatment course is suggested for post-mastectomy advanced breast radiotherapy. It is more important when wedge filters are applied to homogenize dose distribution. PMID:27358592

  10. Differences in pyrimidine dimer removal between rat skin cells in vitro and in vivo

    SciTech Connect

    Mullaart, E.; Lohman, P.H.; Vijg, J.

    1988-03-01

    Pyrimidine dimers, the most abundant type of DNA lesions induced by ultraviolet light (UV), are rapidly repaired in human skin fibroblasts in vitro. In the same cell type from rats, however, there is hardly any removal of such dimers. To investigate whether this low capacity of rat skin cells to repair lesions in their DNA is an inherent characteristic of this species or an artifact due to cell culturing, we measured the removal of UV-induced pyrimidine dimers from rat epidermal keratinocytes both in vitro and in vivo. Epidermal keratinocytes in vitro were unable to remove any dimers over the first 3 h after UV-irradiation, while only about 20% was removed during a repair period of 24 h. In this respect, these cells were not different from cultured rat fibroblasts. In contrast to the results obtained with keratinocytes in vitro, we observed a rapid repair of pyrimidine dimers in UV-irradiated keratinocytes in vivo over the first 3 h; this rapid repair phase was followed by a much slower repair phase between 3 and 24 h. These results are discussed in terms of the possibility that mammalian cells are able to switch from one DNA repair pathway to another.

  11. Real-time in vivo imaging collagen in lymphedematous skin using multiphoton microscopy.

    PubMed

    Wu, Xiufeng; Zhuo, Shuangmu; Chen, Jianxin; Liu, Ningfei

    2011-01-01

    Changes of dermal collagen are characteristic for chronic lymphedema. To evaluate these changes, a real-time imaging based on two-photon excited fluorescence and second-harmonic generation was developed for investigating collagen of lymphedematous mouse and rat tail skin in vivo. Our findings showed that the technique could image the morphological changes and distribution of collagen in lymphedematous mouse and rat tail skin in vivo. More importantly, it may allow visualization of dynamic collagen alteration during the progression of lymphedema. Our findings demonstrated that multiphoton microscopy may have potential in a clinical setting as an in vivo diagnostic and monitoring system for therapy in lymphology.

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

    PubMed

    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.

  13. In vivo skin capacitive imaging analysis by using grey level co-occurrence matrix (GLCM).

    PubMed

    Ou, Xiang; Pan, Wei; Xiao, Perry

    2014-01-02

    We present our latest work on in vivo skin capacitive imaging analysis by using grey level co-occurrence matrix (GLCM). The in vivo skin capacitive images were taken by a capacitance based fingerprint sensor, the skin capacitive images were then analysed by GLCM. Four different GLCM feature vectors, angular second moment (ASM), entropy (ENT), contrast (CON) and correlation (COR), are selected to describe the skin texture. The results show that angular second moment increases as age increases, and entropy decreases as age increases. The results also suggest that the angular second moment values and the entropy values reflect more about the skin texture, whilst the contrast values and the correlation values reflect more about the topically applied solvents. The overall results shows that the GLCM is an effective way to extract and analyse the skin texture information, which can potentially be a valuable reference for evaluating effects of medical and cosmetic treatments.

  14. Skin imaged by femtosecond laser irradiation: a risk assessment for in vivo applications

    NASA Astrophysics Data System (ADS)

    Fischer, F.; Volkmer, B.; Puschmann, S.; Greinert, R.; Breitbart, W.; Kiefer, J.; Wepf, R.

    2006-04-01

    During the last couple of years new imaging techniques using femtosecond lasers (fs-lasers) in the near infrared spectral range evolved for a variety of in vitro applications. We wanted to know, whether fs-lasers have a non-invasive imaging potential for in vivo applications for human skin. So far, little is known about possible risks of this irradiation type. To estimate the risk of irradiation damage in human skin we used a "biological dosimeter" in this investigation. We irradiated fresh human skin samples with both an fs-laser and a solar simulator (UV-source) for comparison. DNA damage introduced in the epidermis was evaluated using fluorescent antibodies against cyclobutane-pyrimidin-dimers (CPDs) in combination with immuno-fluorescence image analysis. Various fs-irradiation regimes were evaluated differing in laser power and step width of horizontal irradiation scans. When using 15 mW or 30 mW fs-laser power combined with horizontal irradiation scans applied every 5 mm in depth around the epidermal-dermal junction no induction of CPDs was found. However, induction of CPDs could be seen using 60 mW laser power and 5 μm step width. Narrowing the step width to 1 mm and using increasing laser power (up to 35 mW) from the surface of the skin to the epidermis led to CPD formation, too. Quantitative comparison of CPD production at various laser regimes with CPD production using a solar simulator was done. We could show that the number of CPDs formed by the 60 mW laser irradiation regime is comparable to an UV-irradiation giving 0.6 MED (minimal erythemal dose). The smaller step width laser irradiation regime (1 μm step width and up to 35 mW) was comparable to a UV-irradiation regime resulting in 0.45 MED.

  15. In vivo measurements of skin barrier: comparison of different methods and advantages of laser scanning microscopy

    NASA Astrophysics Data System (ADS)

    Patzelt, A.; Sterry, W.; Lademann, J.

    2010-12-01

    A major function of the skin is to provide a protective barrier at the interface between external environment and the organism. For skin barrier measurement, a multiplicity of methods is available. As standard methods, the determination of the transepidermal water loss (TEWL) as well as the measurement of the stratum corneum hydration, are widely accepted, although they offer some obvious disadvantages such as increased interference liability. Recently, new optical and spectroscopic methods have been introduced to investigate skin barrier properties in vivo. Especially, laser scanning microscopy has been shown to represent an excellent tool to study skin barrier integrity in many areas of relevance such as cosmetology, occupation, diseased skin, and wound healing.

  16. Ranking of aqueous surfactant-humectant systems based on an analysis of in vitro and in vivo skin barrier perturbation measurements.

    PubMed

    Ghosh, Saswata; Hornby, Sidney; Grove, Gary; Zerwick, Charles; Appa, Yohini; Blankschtein, Daniel

    2007-01-01

    We propose that skin electrical current measurements can be used in vitro to effectively rank aqueous solutions containing surfactants and humectants (the enhancer) contacting the skin, relative to a PBS aqueous solution (the control) contacting the skin, based on their ability to perturb the skin aqueous pores. Specifically, we develop an in vitro ranking metric using the increase in the skin electrical current induced by an enhancer relative to the control. Aqueous contacting solutions containing (i) surfactants [SDS (sodium dodecyl sulfate)] and C(12)E(6) [dodecyl hexa (ethylene oxide)], (ii) humectants (glycerol and propylene glycol), and (iii) a control (PBS) were studied. Utilizing the new in vitro ranking metric, these aqueous contacting solutions were ranked as follows (from the mildest to the harshest): glycerol < propylene glycol < PBS < C(12)E(6) < SDS. In order to further develop this ranking methodology, which can potentially lead to the reduction, or elimination, of costly and time-consuming procedures, such as human and animal testing and trial-and-error screening in vivo, it was important to correlate the findings of the in vitro ranking metric with direct in vivo skin barrier measurements. For this purpose, in vivo soap chamber measurements, including transepidermal water loss, visual skin dryness, and chromameter erythema measurements, were carried out on human volunteers using the aqueous surfactant-humectant solutions described above. The results of these in vivo measurements were found to be consistent with the ranking results obtained using the in vitro ranking metric. To further explore the validity of our model and to verify the skin barrier mitigating effect of glycerol, in vivo soap chamber measurements were carried out for aqueous SDS solutions containing 10 wt% added glycerol. These in vivo measurements support our recent in vitro finding that glycerol reduces the average radius and the pore number density of the skin aqueous pores, such

  17. Oncogenic Radiation Abscopal Effects In Vivo: Interrogating Mouse Skin

    SciTech Connect

    Mancuso, Mariateresa; Leonardi, Simona; Giardullo, Paola; Pasquali, Emanuela; Tanori, Mirella; De Stefano, Ilaria; Casciati, Arianna; Naus, Christian C.; Pazzaglia, Simonetta; Saran, Anna

    2013-08-01

    Purpose: To investigate the tissue dependence in transmission of abscopal radiation signals and their oncogenic consequences in a radiosensitive mouse model and to explore the involvement of gap junction intercellular communication (GJIC) in mediating radiation tumorigenesis in off-target mouse skin. Methods and Materials: Patched1 heterozygous (Ptch1{sup +/−}) mice were irradiated at postnatal day 2 (P2) with 10 Gy of x-rays. Individual lead cylinders were used to protect the anterior two-thirds of the body, whereas the hindmost part was directly exposed to radiation. To test the role of GJICs and their major constituent connexin43 (Cx43), crosses between Ptch1{sup +/−} and Cx43{sup +/−} mice were similarly irradiated. These mouse groups were monitored for their lifetime, and skin basal cell carcinomas (BCCs) were counted and recorded. Early responses to DNA damage - Double Strand Breaks (DSBs) and apoptosis - were also evaluated in shielded and directly irradiated skin areas. Results: We report abscopal tumor induction in the shielded skin of Ptch1{sup +/−} mice after partial-body irradiation. Endpoints were induction of early nodular BCC-like tumors and macroscopic infiltrative BCCs. Abscopal tumorigenesis was significantly modulated by Cx43 status, namely, Cx43 reduction was associated with decreased levels of DNA damage and oncogenesis in out-of-field skin, suggesting a key role of GJIC in transmission of oncogenic radiation signals to unhit skin. Conclusions: Our results further characterize the nature of abscopal responses and the implications they have on pathologic processes in different tissues, including their possible underlying mechanistic bases.

  18. The in vivo melanocytotoxicity and depigmenting potency of N-2,4-acetoxyphenyl thioethyl acetamide in the skin and hair.

    PubMed

    Jimbow, M; Marusyk, H; Jimbow, K

    1995-10-01

    It has been shown previously that N-acetyl-4-S-cysteaminylphenol (N-Ac-4-S-CAP) is a tyrosinase substrate and a potent depigmenting agent of dark skin and black hair. The present study evaluated the depigmenting potency of an acetyl derivative of N-Ac-4-S-CAP, N-2,4-acetoxyphenyl thioethyl acetamide (NAP-TEA) in the skin and hair. We tested for (i) in vitro metabolites in the skin after topical application, and (ii) in vivo depigmenting potency in the skin and hair. We found that NAP-TEA was stable in water, but was converted to N-Ac-4-S-CAP after topical application to human skin. Therefore, although NAP-TEA was not a tyrosinase substrate, it could react with tyrosinase after being converted to N-Ac-4-S-CAP by O-deacetylation in vivo. NAP-TEA produced marked depigmentation of dark skin (Yucatan pig) after daily topical application. When given by intraperitoneal injection, it resulted in complete loss of hair colour (white) grown at the epilated site in adult C57 black mice after daily administration for 10 days, and incomplete loss of coat colour (silver grey) in newborn C57 black mice after a single administration. The depigmentation of the skin and hair was reversible. Split-dopa preparation and electron microscopy indicated that this depigmentation is primarily related to (i) a marked decrease in the number of functioning melanocytes and melanized melanosomes, (ii) a decrease in the number of melanosomes transferred to keratinocytes, and (iii) selective degeneration/inactivation of melanocytes, and deposition of melanin-like material in the Golgi cisternae, coated vesicles and melanosomes, where tyrosinase is reported to be located. We propose the NAP-TEA is converted in vivo to N-Ac-4-S-CAP which, via interaction with tyrosinase, causes reversible depigmentation of the skin and hair.

  19. The optics of human skin

    SciTech Connect

    Anderson, R.R.; Parrish, J.A.

    1981-07-01

    An integrated review of the transfer of optical radiation into human skin is presented, aimed at developing useful models for photomedicine. The component chromophores of epidermis and stratum corneum in general determine the attenuation of radiation in these layers, moreso than does optical scattering. Epidermal thickness and melanization are important factors for UV wavelengths less than 300 nm, whereas the attenuation of UVA (320-400 nm) and visible radiation is primarily via melanin. The selective penetration of all optical wavelengths into psoriatic skin can be maximized by application of clear lipophilic liquids, which decrease regular reflectance by a refractive-index matching mechanism. Sensitivity to wavelengths less than 320 nm can be enhanced by prolonged aqueous bathing, which extracts urocanic acid and other diffusible epidermal chromophores. Optical properties of the dermis are modelled using the Kubelka-Munk approach, and calculations of scattering and absorption coefficients are presented. This simple approach allows estimates of the penetration of radiation in vivo using noninvasive measurements of cutaneous spectral remittance (diffuse reflectance). Although the blood chromophores Hb, HbO/sup 2/, and bilirubin determine dermal absorption of wavelengths longer than 320 nm, scattering by collagen fibers largely determines the depths to which these wavelengths penetrate the dermis, and profoundly modifies skin colors. An optical ''window'' exists between 600 and 1300 nm, which offers the possibility of treating large tissue volumes with certain long-wavelength photosensitizers. Moreover, whenever photosensitized action spectra extend across the near UV and/or visible spectrum, judicious choice of wavelengths allows some selection of the tissue layers directly affected.

  20. Non-invasive in vivo methods for investigation of the skin barrier physical properties.

    PubMed

    Darlenski, R; Sassning, S; Tsankov, N; Fluhr, J W

    2009-06-01

    Skin as an organ of protection covers the body and accomplishes multiple defensive functions. The intact skin represents a barrier to the uncontrolled loss of water, proteins, and plasma components from the organism. Due to its complex structure, the epidermal barrier with its major component, stratum corneum, is the rate-limiting unit for the penetration of exogenous substances through the skin. The epidermal barrier is not a static structure. The permeability barrier status can be modified by different external and internal factors such as climate, physical stressors, and a number of skin and systemic diseases. Today, different non-invasive approaches are used to monitor the skin barrier physical properties in vivo. The quantification of parameters such as transepidermal water loss, stratum corneum hydration, and skin surface acidity is essential for the integral evaluation of the epidermal barrier status. Novel methods such as in vivo confocal Raman microspectroscopy offer the possibility for precise and detailed characterization of the skin barrier. This paper will allow the readership to get acquainted with the non-invasive, in vivo methods for the investigation of the skin barrier.

  1. Non-invasive measurement of micro-area skin impedance in vivo

    NASA Astrophysics Data System (ADS)

    Li, Dachao; Liang, Wenshuai; Liu, Tongkun; Yu, Haixia; Xu, Kexin

    2011-12-01

    Volume measurement of interstitial fluid transdermally extracted is important in continuous glucose monitoring instrument. The volume of transdermally extracted interstitial fluid could be determined by a skin permeability coefficient. If the skin impedance which is the indicator of skin permeability coefficient can be accurately measured, the volume of interstitial fluid can be calculated based on the relationship between the indicator and the skin permeability coefficient. The possibility of using the skin impedance to indicate the skin permeability coefficient is investigated. A correlation model between the skin impedance and the skin permeability coefficient is developed. A novel non-invasive method for in vivo, real-time, and accurate measurement of skin impedance within a micro skin area is brought forward. The proposed measurement method is based on the theory that organisms saliva and interstitial fluid are equipotential. An electrode is put on the surface of a micro skin area and another one is put in the mouth to be fully contacted with saliva of an animal in the experiments. The electrode in mouth is used to replace the implantable subcutaneous electrode for non-invasive measurement of skin impedance in vivo. A biologically compatible AC current with amplitude of 100mv and frequency of 10Hz is applied to stimulate the micro skin area by the two electrodes. And then the voltage and current between the two electrodes are measured to calculate the skin impedance within a micro skin area. The measurement results by electrode in mouth are compared with the results by subcutaneous electrode in animal experiments and they are consistent so the proposed measurement method is verified well. The effect of moisture and pressure for the measurement is also studied in the paper.

  2. Monogenic human skin disorders.

    PubMed

    Lemke, Johannes R; Kernland-Lang, Kristin; Hörtnagel, Konstanze; Itin, Peter

    2014-01-01

    Human genodermatoses represent a broad and partly confusing spectrum of countless rare diseases with confluent and overlapping phenotypes often impeding a precise diagnosis in an affected individual. High-throughput sequencing techniques have expedited the identification of novel genes and have dramatically simplified the establishment of genetic diagnoses in such heterogeneous disorders. The precise genetic diagnosis of a skin disorder is crucial for the appropriate counselling of patients and their relatives regarding the course of the disease, prognosis and recurrence risks. Understanding the underlying pathophysiology is a prerequisite to understanding the disease and developing specific, targeted or individualized therapeutic approaches. We aimed to create a comprehensive overview of human genodermatoses and their respective genetic aetiology known to date. We hope this may represent a useful tool in guiding dermatologists towards genetic diagnoses, providing patients with individual knowledge on the respective disorder and applying novel research findings to clinical practice.

  3. Solid lipid nanoparticles as carrier for sunscreens: in vitro release and in vivo skin penetration.

    PubMed

    Wissing, S A; Müller, R H

    2002-06-17

    The aim of this study was the comparison of two different formulations (solid lipid nanoparticles (SLN) and conventional o/w emulsion) as carrier systems for the molecular sunscreen oxybenzone. The influence of the carrier on the rate of release was studied in vitro with a membrane-free model. The release rate could be decreased by up to 50% with the SLN formulation. Further in vitro measurements with static Franz diffusion cells were performed. In vivo, penetration of oxybenzone into stratum corneum on the forearm was investigated by the tape stripping method. It was shown that the rate of release is strongly dependent upon the formulation and could be decreased by 30-60% in SLN formulations. In all test models, oxybenzone was released and penetrated into human skin more quickly and to a greater extent from the emulsions. The rate of release also depends upon the total concentration of oxybenzone in the formulation. In vitro-in vivo correlations could be made qualitatively.

  4. Study of the vitamins A, E and C esters penetration into the skin by confocal Raman spectroscopy in vivo

    NASA Astrophysics Data System (ADS)

    Mogilevych, Borys; Isensee, Debora; Rangel, Joao L.; Dal Pizzol, Carine; Martinello, Valeska C. A.; Dieamant, Gustavo C.; Martin, Airton A.

    2015-06-01

    Vitamins A, E and C play important role in skin homeostasis and protection. Hence, they are extensively used in many cosmetic and cosmeceutic products. However, their molecules are unstable, and do not easily penetrate into the skin, which drastically decreases its efficiency in topical formulations. Liposoluble derivative of the vitamin A - retinyl palmitate, vitamin E - tocopheryl acetate, and vitamin C - tetraisopalmitoyl ascorbic acid, are more stable, and are frequently used as an active ingredient in cosmetic products. Moreover, increased hydrophobicity of these molecules could lead to a higher skin penetration. The aim of this work is to track and compare the absorption of the liposoluble derivatives of the vitamins and their encapsulated form, into the healthy human skin in vivo. We used Confocal Raman Spectroscopy (CRS) that is proven to be helpful in label-free non-destructive investigation of the biochemical composition and molecular conformational analysis of the biological samples. The measurements were performed in the volar forearm of the 10 healthy volunteers. Skin was treated with both products, and Raman spectra were obtained after 15 min, 3 hours, and 6 hours after applying the formulation. 3510 Skin Composition Analyzer (River Diagnostics, The Netherlands) with 785 nm laser excitation was used to acquire information in the fingerprint region. Significant difference in permeation of the products was observed. Whereas only free form of retinyl palmitate penetrate the skin within first 15 minutes, all three vitamin derivatives were present under the skin surface in case of nanoparticulated form.

  5. In vivo gene silencing following non-invasive siRNA delivery into the skin using a novel topical formulation.

    PubMed

    Hegde, Vikas; Hickerson, Robyn P; Nainamalai, Sitheswaran; Campbell, Paul A; Smith, Frances J D; McLean, W H Irwin; Pedrioli, Deena M Leslie

    2014-12-28

    Therapeutics based on short interfering RNAs (siRNAs), which act by inhibiting the expression of target transcripts, represent a novel class of potent and highly specific next-generation treatments for human skin diseases. Unfortunately, the intrinsic barrier properties of the skin combined with the large size and negative charge of siRNAs make epidermal delivery of these macromolecules quite challenging. To help evaluate the in vivo activity of these therapeutics and refine delivery strategies we generated an innovative reporter mouse model that predominantly expresses firefly luciferase (luc2p) in the paw epidermis--the region of murine epidermis that most closely models the tissue architecture of human skin. Combining this animal model with state-of-the-art live animal imaging techniques, we have developed a real-time in vivo analysis work-flow that has allowed us to compare and contrast the efficacies of a wide range nucleic acid-based gene silencing reagents in the skin of live animals. While inhibition was achieved with all of the reagents tested, only the commercially available "self-delivery" modified Accell-siRNAs (Dharmacon) produced potent and sustained in vivo gene silencing. Together, these findings highlight just how informative reliable reporter mouse models can be when assessing novel therapeutics in vivo. Using this work-flow, we developed a novel clinically-relevant topical formulation that facilitates non-invasive epidermal delivery of unmodified and "self-delivery" siRNAs. Remarkably, a sustained >40% luc2p inhibition was observed after two 1-hour treatments with Accell-siRNAs in our topical formulation. Importantly, our ability to successfully deliver siRNA molecules topically brings these novel RNAi-based therapeutics one-step closer to clinical use.

  6. The effects of heat on skin barrier function and in vivo dermal absorption.

    PubMed

    Oliveira, Gabriela; Leverett, Jesse C; Emamzadeh, Mandana; Lane, Majella E

    2014-04-10

    Enhanced delivery of ingredients across the stratum corneum (SC) is of great interest for improving the efficacy of topically applied formulations. Various methods for improving dermal penetration have been reported including galvanic devices and micro-needles. From a safety perspective it is important that such approaches do not compromise SC barrier function. This study investigates the influence of topically applied heat in vivo on the dermal uptake and penetration of a model active, allantoin from gel and lotion formulations. A custom designed device was used to deliver 42°C for 30s daily to human subjects after application of two formulations containing allantoin. The results were compared with sites treated with formulations containing no active and no heat, and a control site. In addition to penetration of allantoin, the integrity of the SC was monitored using trans-epidermal water loss (TEWL) measurements. The results showed that just 30s of 42°C topically applied heat was enough to cause significantly more penetration of allantoin from the lotion formulation compared with no application of heat. TEWL data indicated that the integrity of the skin was not compromised by the treatment. However, the application of heat did not promote enhanced penetration of the active from the gel formulation. Vehicle composition is therefore an important factor when considering thermal enhancement strategies for targeting actives to the skin.

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

    NASA Astrophysics Data System (ADS)

    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.

  8. Enhanced in vitro and in vivo skin deposition of apigenin delivered using ethosomes.

    PubMed

    Shen, Li-Na; Zhang, Yong-Tai; Wang, Qin; Xu, Ling; Feng, Nian-Ping

    2014-01-02

    The aim of this study was to develop and evaluate a novel topical delivery system for apigenin by using ethosomes. An optimal apigenin-loaded ethosome formulation was identified by means of uniform design experiments. Skin deposition and transdermal flux of apigenin loaded in ethosomes, liposomes, and deformable liposomes were compared in vitro and in vivo. The efficiency of apigenin encapsulation increased with an increase in the amount of phospholipids in ethosome formulations. Moreover, skin deposition and transdermal flux of apigenin improved with an increase in the levels of phospholipids (Lipoid S 75) and short-chain alcohols (propylene glycol and ethanol), but decreased with an increase in the ratio of propylene glycol to ethanol. Profiles of skin deposition versus time for ethosomes varied markedly between in vivo and in vitro studies compared with those of liposomes or deformable liposomes. Optimized ethosomes showed superior skin targeting both in vitro and in vivo. Moreover, they had the strongest effect on reduction of cyclooxygenase-2 levels in mouse skin inflammation induced by ultraviolet B (UVB) light. Therefore, apigenin-loaded ethosomes represent a promising therapeutic approach for the treatment of UVB-induced skin inflammation.

  9. In vitro Percutaneous Absorption of Niacinamide and Phytosterols and in vivo Evaluation of their Effect on Skin Barrier Recovery.

    PubMed

    Offerta, Alessia; Bonina, Francesco; Gasparri, Franco; Zanardi, Andrea; Micicche, Lucia; Puglia, Carmelo

    2016-01-01

    In this study, we evaluated different strategies to optimize the percutaneous absorption of niacinamide (NA) and soy phytosterols (FITO) by making use of solid lipid nanoparticles (SLN) and penetration enhancers, such as the hydrogenated lecithin. The evaluation of the skin permeation of NA and FITO has been effected in vitro using excised human skin (i.e., stratum corneum-epidermis or SCE). Furthermore, we evaluated the in vivo effect that NA and FITO has on skin barrier recovery after the topical application; using the extent of methyl nicotinate (MN)-induced erythema in damaged skin as a parameter to determine the rate of stratum corneum recovery. Results pointed out the importance of these strategies as valid tools for NA and FITO topical delivery. In fact, soy lecithin based formulations were able to increase the percutaneous absorption of the two active ingredients, while SLN guaranteed an interesting delayed and sustained release of FITO. In vivo evaluation showed clearly that the formulation containing both the actives (NA and FITO) is able to recover about 95% of skin barrier integrity eight days after tape stripping. This effect is probably due to the "synergistic effect" of NA and FITO.

  10. Polarization speckle imaging as a potential technique for in vivo skin cancer detection.

    PubMed

    Tchvialeva, Lioudmila; Dhadwal, Gurbir; Lui, Harvey; Kalia, Sunil; Zeng, Haishan; McLean, David I; Lee, Tim K

    2013-06-01

    Skin cancer is the most common cancer in the Western world. In order to accurately detect the disease, especially malignant melanoma-the most fatal form of skin cancer-at an early stage when the prognosis is excellent, there is an urgent need to develop noninvasive early detection methods. We believe that polarization speckle patterns, defined as a spatial distribution of depolarization ratio of traditional speckle patterns, can be an important tool for skin cancer detection. To demonstrate our technique, we conduct a large in vivo clinical study of 214 skin lesions, and show that statistical moments of the polarization speckle pattern could differentiate different types of skin lesions, including three common types of skin cancers, malignant melanoma, squamous cell carcinoma, basal cell carcinoma, and two benign lesions, melanocytic nevus and seborrheic keratoses. In particular, the fourth order moment achieves better or similar sensitivity and specificity than many well-known and accepted optical techniques used to differentiate melanoma and seborrheic keratosis.

  11. Polarization speckle imaging as a potential technique for in vivo skin cancer detection

    NASA Astrophysics Data System (ADS)

    Tchvialeva, Lioudmila; Dhadwal, Gurbir; Lui, Harvey; Kalia, Sunil; Zeng, Haishan; McLean, David I.; Lee, Tim K.

    2013-06-01

    Skin cancer is the most common cancer in the Western world. In order to accurately detect the disease, especially malignant melanoma-the most fatal form of skin cancer-at an early stage when the prognosis is excellent, there is an urgent need to develop noninvasive early detection methods. We believe that polarization speckle patterns, defined as a spatial distribution of depolarization ratio of traditional speckle patterns, can be an important tool for skin cancer detection. To demonstrate our technique, we conduct a large in vivo clinical study of 214 skin lesions, and show that statistical moments of the polarization speckle pattern could differentiate different types of skin lesions, including three common types of skin cancers, malignant melanoma, squamous cell carcinoma, basal cell carcinoma, and two benign lesions, melanocytic nevus and seborrheic keratoses. In particular, the fourth order moment achieves better or similar sensitivity and specificity than many well-known and accepted optical techniques used to differentiate melanoma and seborrheic keratosis.

  12. In vitro and in vivo percutaneous absorption of retinol from cosmetic formulations: significance of the skin reservoir and prediction of systemic absorption.

    PubMed

    Yourick, Jeffrey J; Jung, Connie T; Bronaugh, Robert L

    2008-08-15

    The percutaneous absorption of retinol (Vitamin A) from cosmetic formulations was studied to predict systemic absorption and to understand the significance of the skin reservoir in in vitro absorption studies. Viable skin from fuzzy rat or human subjects was assembled in flow-through diffusion cells for in vitro absorption studies. In vivo absorption studies using fuzzy rats were performed in glass metabolism cages for collection of urine, feces, and body content. Retinol (0.3%) formulations (hydroalcoholic gel and oil-in-water emulsion) containing (3)H-retinol were applied and absorption was measured at 24 or 72 h. All percentages reported are % of applied dose. In vitro studies using human skin and the gel and emulsion vehicles found 0.3 and 1.3% retinol, respectively, in receptor fluid at 24 h. Levels of absorption in the receptor fluid increased over 72 h with the gel and emulsion vehicles. Using the gel vehicle, in vitro rat skin studies found 23% in skin and 6% in receptor fluid at 24 h, while 72-h studies found 18% in skin and 13% in receptor fluid. Thus, significant amounts of retinol remained in rat skin at 24 h and decreased over 72 h, with proportional increases in receptor fluid. In vivo rat studies with the gel found 4% systemic absorption of retinol after 24 h and systemic absorption did not increase at 72 h. Retinol remaining in rat skin after in vivo application was 18% and 13% of the applied dermal dose after 24 and 72 h, respectively. Similar observations were made with the oil-in water emulsion vehicle in the rat. Retinol formed a reservoir in rat skin both in vivo and in vitro. Little additional retinol was bioavailable after 24 h. Comparison of these in vitro and in vivo results for absorption through rat skin indicates that the 24-h in vitro receptor fluid value accurately estimated 24-h in vivo systemic absorption. Therefore, the best single estimate of retinol systemic absorption from in vitro human skin studies is the 24-h receptor fluid

  13. In vitro and in vivo percutaneous absorption of retinol from cosmetic formulations: Significance of the skin reservoir and prediction of systemic absorption

    SciTech Connect

    Yourick, Jeffrey J. Jung, Connie T.; Bronaugh, Robert L.

    2008-08-15

    The percutaneous absorption of retinol (Vitamin A) from cosmetic formulations was studied to predict systemic absorption and to understand the significance of the skin reservoir in in vitro absorption studies. Viable skin from fuzzy rat or human subjects was assembled in flow-through diffusion cells for in vitro absorption studies. In vivo absorption studies using fuzzy rats were performed in glass metabolism cages for collection of urine, feces, and body content. Retinol (0.3%) formulations (hydroalcoholic gel and oil-in-water emulsion) containing {sup 3}H-retinol were applied and absorption was measured at 24 or 72 h. All percentages reported are % of applied dose. In vitro studies using human skin and the gel and emulsion vehicles found 0.3 and 1.3% retinol, respectively, in receptor fluid at 24 h. Levels of absorption in the receptor fluid increased over 72 h with the gel and emulsion vehicles. Using the gel vehicle, in vitro rat skin studies found 23% in skin and 6% in receptor fluid at 24 h, while 72-h studies found 18% in skin and 13% in receptor fluid. Thus, significant amounts of retinol remained in rat skin at 24 h and decreased over 72 h, with proportional increases in receptor fluid. In vivo rat studies with the gel found 4% systemic absorption of retinol after 24 h and systemic absorption did not increase at 72 h. Retinol remaining in rat skin after in vivo application was 18% and 13% of the applied dermal dose after 24 and 72 h, respectively. Similar observations were made with the oil-in water emulsion vehicle in the rat. Retinol formed a reservoir in rat skin both in vivo and in vitro. Little additional retinol was bioavailable after 24 h. Comparison of these in vitro and in vivo results for absorption through rat skin indicates that the 24-h in vitro receptor fluid value accurately estimated 24-h in vivo systemic absorption. Therefore, the best single estimate of retinol systemic absorption from in vitro human skin studies is the 24-h receptor

  14. Measurement of diffusion of fluorescent compounds and autofluorescence in skin in vivo using a confocal instrument

    NASA Astrophysics Data System (ADS)

    Buttenschoen, K. K.; Sutton, E. E.; Daly, D.; Girkin, J. M.

    2016-02-01

    Using compact and affordable instrumentation based upon fluorescent confocal imaging we have tracked the movement of autofluorescent compounds through skin in near real time with high temporal and spatial resolution and sensitivity. The ability to measure the diffusion of compounds through skin with such resolution plays an important role for applications such as monitoring the penetration of pharmaceuticals applied to skin and assessing the integrity of the skin barrier. Several measurement methods exist, but they suffer from a number of problems such as being slow, expensive, non-portable and lacking sensitivity. To address these issues, we adapted a technique that we previously developed for tracking fluorescent compounds in the eye to measure the autofluorescence and the diffusion of externally applied fluorescent compounds in skin in vivo. Results are presented that show the change in autofluorescence of the volar forearm over the course of a week. We furthermore demonstrate the ability of the instrument to measure the diffusion speed and depth of externally applied fluorescent compounds both in healthy skin and after the skin barrier function has been perturbed. The instrument is currently being developed further for increased sensitivity and multi-wavelength excitation. We believe that the presented instrument is suitable for a large number of applications in fields such as assessment of damage to the skin barrier, development of topical and systemic medication and tracking the diffusion of fluorescent compounds through skin constructs as well as monitoring effects of skin products and general consumer products which may come into contact with the skin.

  15. In vivo antinuclear antibodies of the skin: A rare phenomenon on direct immunofluorescence.

    PubMed

    Chhabra, Seema; Arora, Sandeep Kumar; Minz, Ranjana Walker; Dogra, Suneel

    2013-04-15

    Detection of immunoglobulins in epidermal cell nuclei or in vivo antinuclear antibodies on direct immunoflorescence microscopy of skin biopsies is an easily detectable immunopathologic feature. It is an unusual, but not totally rare, occurrence in systemic connective tissue disorders. This positive epidermal nuclear reaction is found to be commonly associated with immunoglobulin G.

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

    PubMed

    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.

  17. Multiple sulfatase deficiency (mucosulfatidosis): impaired degradation of labeled sulfated compounds in cultured skin fibroblasts in vivo.

    PubMed

    Eto, Y; Numaguchi, S; Tahara, T; Rennert, O M

    1980-10-01

    Skin fibroblasts from a Japanese patient with multiple sulfatase deficiency (MSD) (Mucosulfatidosis) were studied with regard to metabolism of various sulfated compounds in vivo. Several sulfatase activities (arylsulfatases A, B and C, cholesterol sulfatase, heparin N-sulfatase) were deficient in skin fibroblasts grown in F-10 CO2 medium. The accumulation and degradation of 35S-sulfatide, 35S-mucopolysaccharides, 14C-cholesterol sulfate by MSD cells were also studied, comparing them to control, Hunter and metachromatic leukodystrophy cells. MSD fibroblasts accumulated and failed to degrade these compounds in vivo. Cholesterol sulfate was also incorporated into the control and pathological cells, and MSD cells were unable to hydrolyze cholesterol sulfate, though cholesterol sulfate is known to be hydrolyzed in the non-lysosomal subfraction. From these data it is clear that multiple enzyme deficiencies in MSD fibroblasts can be demonstrated in vivo.

  18. Skin decontamination with mineral cationic carrier against sarin determined in vivo.

    PubMed

    Vucemilović, Ante; Hadzija, Mirko; Jukić, Ivan

    2009-06-01

    Our Institute's nuclear, biological, and chemical defense research team continuously investigates and develops preparations for skin decontamination against nerve agents. In this in vivo study, we evaluated skin decontamination efficacy against sarin by a synthetic preparation called Mineral Cationic Carrier (MCC) with known ion exchange, absorption efficacy and bioactive potential. Mice were treated with increasing doses of sarin applied on their skin, and MCC was administered immediately after contamination. The results showed that decontamination with MCC could achieve therapeutic efficacy corresponding to 3 x LD(50) of percutaneous sarin and call for further research.

  19. Enhanced optical clearing of skin in vivo and optical coherence tomography in-depth imaging

    NASA Astrophysics Data System (ADS)

    Wen, Xiang; Jacques, Steven L.; Tuchin, Valery V.; Zhu, Dan

    2012-06-01

    The strong optical scattering of skin tissue makes it very difficult for optical coherence tomography (OCT) to achieve deep imaging in skin. Significant optical clearing of in vivo rat skin sites was achieved within 15 min by topical application of an optical clearing agent PEG-400, a chemical enhancer (thiazone or propanediol), and physical massage. Only when all three components were applied together could a 15 min treatment achieve a three fold increase in the OCT reflectance from a 300 μm depth and 31% enhancement in image depth Zthreshold.

  20. Relevance of in vivo models in melanoma skin cancer

    SciTech Connect

    Setlow, R.B.

    1995-12-31

    A discussion of possible wavelength dependence of induction of cutaneous malignant melanoma (CMM) is provided. Strengths and weaknesses of various experimental approaches to better understanding of the prevalence of CMM in different human populations including latitude effects are compared. Further the advantages and limitations of the use of the laboratory opossum (Monodelphis domestic), transgenic mice containing SV40 ongogene sequences under tyrosinase promoter control, and a backcross hybrid fish of the genus Xenophorus are contrasted.

  1. Analysis of Reparative Activity of Platelet Lysate: Effect on Cell Monolayer Recovery In Vitro and Skin Wound Healing In Vivo.

    PubMed

    Sergeeva, N S; Shanskii, Ya D; Sviridova, I K; Karalkin, P A; Kirsanova, V A; Akhmedova, S A; Kaprin, A D

    2016-11-01

    Platelet lysate prepared from donor platelet concentrate and pooled according to a developed technique stimulates migration of multipotent mesenchymal stromal cells of the human adipose tissue and promotes healing of the monolayer defect in cultures of human fibroblasts and multipotent mesenchymal stromal cells in vitro in concentrations close those of fetal calf serum (5-10%). Lysate of platelets from platelet-rich rat blood plasma stimulated healing of the skin defect by promoting epithelialization and granulation tissue formation. The regenerative properties of platelet lysate in vivo increased with increasing its concentration.

  2. Automated in vivo 3D high-definition optical coherence tomography skin analysis system.

    PubMed

    Ai Ping Yow; Jun Cheng; Annan Li; Srivastava, Ruchir; Jiang Liu; Wong, Damon Wing Kee; Hong Liang Tey

    2016-08-01

    The in vivo assessment and visualization of skin structures can be performed through the use of high resolution optical coherence tomography imaging, also known as HD-OCT. However, the manual assessment of such images can be exhaustive and time consuming. In this paper, we present an analysis system to automatically identify and quantify the skin characteristics such as the topography of the surface of the skin and thickness of the epidermis in HD-OCT images. Comparison of this system with manual clinical measurements demonstrated its potential for automatic objective skin analysis and diseases diagnosis. To our knowledge, this is the first report of an automated system to process and analyse HD-OCT skin images.

  3. Genome Wide Evaluation of Normal Human Tissue in Response to Controlled, In vivo Low-Dose Low LET Ionizing Radiation Exposure: Pathways and Mechanisms Final Report, September 2013

    SciTech Connect

    Rocke, David M.

    2013-09-09

    During course of this project, we have worked in several areas relevant to low-dose ionizing radiation. Using gene expression to measure biological response, we have examined the response of human skin exposed in-vivo to radation, human skin exposed ex-vivo to radiation, and a human-skin model exposed to radiation. We have learned a great deal about the biological response of human skin to low-dose ionizing radiation.

  4. Advances in the in Vivo Raman Spectroscopy of Malignant Skin Tumors Using Portable Instrumentation.

    PubMed

    Kourkoumelis, Nikolaos; Balatsoukas, Ioannis; Moulia, Violetta; Elka, Aspasia; Gaitanis, Georgios; Bassukas, Ioannis D

    2015-06-26

    Raman spectroscopy has emerged as a promising tool for real-time clinical diagnosis of malignant skin tumors offering a number of potential advantages: it is non-intrusive, it requires no sample preparation, and it features high chemical specificity with minimal water interference. However, in vivo tissue evaluation and accurate histopathological classification remain a challenging task for the successful transition from laboratory prototypes to clinical devices. In the literature, there are numerous reports on the applications of Raman spectroscopy to biomedical research and cancer diagnostics. Nevertheless, cases where real-time, portable instrumentations have been employed for the in vivo evaluation of skin lesions are scarce, despite their advantages in use as medical devices in the clinical setting. This paper reviews the advances in real-time Raman spectroscopy for the in vivo characterization of common skin lesions. The translational momentum of Raman spectroscopy towards the clinical practice is revealed by (i) assembling the technical specifications of portable systems and (ii) analyzing the spectral characteristics of in vivo measurements.

  5. Advances in the in Vivo Raman Spectroscopy of Malignant Skin Tumors Using Portable Instrumentation

    PubMed Central

    Kourkoumelis, Nikolaos; Balatsoukas, Ioannis; Moulia, Violetta; Elka, Aspasia; Gaitanis, Georgios; Bassukas, Ioannis D.

    2015-01-01

    Raman spectroscopy has emerged as a promising tool for real-time clinical diagnosis of malignant skin tumors offering a number of potential advantages: it is non-intrusive, it requires no sample preparation, and it features high chemical specificity with minimal water interference. However, in vivo tissue evaluation and accurate histopathological classification remain a challenging task for the successful transition from laboratory prototypes to clinical devices. In the literature, there are numerous reports on the applications of Raman spectroscopy to biomedical research and cancer diagnostics. Nevertheless, cases where real-time, portable instrumentations have been employed for the in vivo evaluation of skin lesions are scarce, despite their advantages in use as medical devices in the clinical setting. This paper reviews the advances in real-time Raman spectroscopy for the in vivo characterization of common skin lesions. The translational momentum of Raman spectroscopy towards the clinical practice is revealed by (i) assembling the technical specifications of portable systems and (ii) analyzing the spectral characteristics of in vivo measurements. PMID:26132563

  6. High resolution in-vivo imaging of skin with full field optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Dalimier, E.; Bruhat, Alexis; Grieve, K.; Harms, F.; Martins, F.; Boccara, C.

    2014-03-01

    Full-field OCT (FFOCT) has the ability to provide en-face images with a very good axial sectioning as well as a very high transverse resolution (about 1 microns in all directions). Therefore it offers the possibility to visualize biological tissues with very high resolution both on the axial native view, and on vertical reconstructed sections. Here we investigated the potential dermatological applications of in-vivo skin imaging with FFOCT. A commercial FFOCT device was adapted for the in-vivo acquisition of stacks of images on the arm, hand and finger. Several subjects of different benign and pathological skin conditions were tested. The images allowed measurement of the stratum corneum and epidermis thicknesses, measurement of the stratum corneum refractive index, size measurement and count of the keratinocytes, visualization of the dermal-epidermal junction, and visualization of the melanin granules and of the melanocytes. Skins with different pigmentations could be discriminated and skin pathologies such as eczema could be identified. The very high resolution offered by FFOCT both on axial native images and vertical reconstructed sections allows for the visualization and measurement of a set of parameters useful for cosmetology and dermatology. In particular, FFOCT is a potential tool for the understanding and monitoring of skin hydration and pigmentation, as well as skin inflammation.

  7. Optical characterization of murine model's in-vivo skin using Mueller matrix polarimetric imaging

    NASA Astrophysics Data System (ADS)

    Mora-Núñez, Azael; Martinez-Ponce, Geminiano; Garcia-Torales, Guillermo

    2015-12-01

    Mueller matrix polarimetric imaging (MMPI) provides a complete characterization of an anisotropic optical medium. Subsequent single value decomposition allows image interpretation in terms of basic optical anisotropies, such as depolarization, diattenuation, and retardance. In this work, healthy in-vivo skin at different anatomical locations of a biological model (Rattus norvegicus) was imaged by the MMPI technique using 532nm coherent illumination. The body parts under study were back, abdomen, tail, and calvaria. Because skin components are randomly distributed and skin thickness depends on its location, polarization measures arise from the average over a single detection element (pixel) and on the number of free optical paths, respectively. Optical anisotropies over the imaged skin indicates, mainly, the presence of components related to the physiology of the explored region. In addition, a MMPI-based comparison between a tumor on the back of one test subject and proximal healthy skin was made. The results show that the single values of optical anisotropies can be helpful in distinguishing different areas of in-vivo skin and also lesions.

  8. Evaluation of Paeonol Skin-Target Delivery from Its Microsponge Formulation: In Vitro Skin Permeation and In Vivo Microdialysis

    PubMed Central

    Liu, Li; Jiang, Xiao; Zhang, Bin; Liu, Zhi-Gang; Li, Xue-Ling; Weng, Li-Dong; Zuo, Ting; Liu, Qiang

    2013-01-01

    The aim of the present study was to design a novel topical skin-target drug-delivery system, the paeonol microsponge, and to investigate its drug-release patterns in dosage form, both in vitro and in vivo. Paeonol microsponges were prepared using the quasi-emulsion solvent-diffusion method. In vitro release studies were carried out using Franz diffusion cells, while in vivo studies were investigated by microdialysis after the paeonol microsponges were incorporated into a cream base. In vitro release studies showed that the drug delivered via microsponges increased the paeonol permeation rate. Ex vivo drug-deposition studies showed that the microsponge formulation improved drug residence in skin. In addition, in vivo microdialysis showed that the values for the area under the concentration versus time curve (AUC) for the paeonol microsponge cream was much higher than that of paeonol cream without microsponges. Maximum time (Tmax) was 220 min for paeonol microsponge cream and 480 min for paeonol cream, while the half-life (t1/2) of paeonol microsponge cream (935.1 min) was almost twice that of paeonol cream (548.6 min) in the skin (n = 3). Meanwhile, in the plasma, the AUC value for paeonol microsponge cream was half that of the paeonol cream. Based on these results, paeonol-loaded microsponge formulations could be a better alternative for treating skin disease, as the formulation increases drug bioavailability by lengthening the time of drug residence in the skin and should reduce side-effects because of the lower levels of paeonol moving into the circulation. PMID:24278204

  9. In vitro and in vivo transdermal delivery capacity of quantum dots through mouse skin

    NASA Astrophysics Data System (ADS)

    Chu, Maoquan; Wu, Qiang; Wang, Jiaxu; Hou, Shengke; Miao, Yi; Peng, Jinliang; Sun, Ye

    2007-11-01

    CdTe quantum dots (QDs) with red fluorescence have been used to study their transdermal delivery capacity through mouse skin. The results showed that the QDs could permeate through skin, either separated from or still attached to live mice. Although the fluorescence emitted by the QDs could only be found in the skin and muscle cells located under the mouse skins coated with QDs, an inductive coupled plasma atomic emission spectrometry (ICP-AES) study indicated that the main organs, such as the heart, liver, spleen, lung, kidney and brain, all contained a significant quantity of Cd atoms. Moreover, these Cd atoms could remain in vivo for at least one week. As a control, the concentration of Cd atoms in normal mice not coated with QDs was very low.

  10. In vivo impedance measurements on nerves and surrounding skeletal muscles in rats and human body.

    PubMed

    Prokhorov, E; Llamas, F; Morales-Sánchez, E; González-Hernández, J; Prokhorov, A

    2002-05-01

    The aim of the work was to use impedance measurements to find the location of nerves under the human skin. In vivo impedance measurements were performed on exposed nervous and muscular tissues of rats. Similarly, the impedance measurements were also performed on the skin of six men, over the median nerve at the wrist, as well as 4-5 mm away from this location. Results obtained with rats have shown that the relative permittivity and conductivity of nerves are larger (by almost two orders of magnitude) than those observed for the muscular tissues surrounding the nerve. The results obtained on human skin in the frequency range of 20-200 kHz, when the electrodes were placed over the nerve, show lower resistance and higher capacitance than in the other areas measured. These preliminary results indicate that it may be possible to use impedance measurements to find the location of exposed nerves and also nerves under the skin.

  11. Effects of Cream Containing Ficus carica L. Fruit Extract on Skin Parameters: In vivo Evaluation

    PubMed Central

    Khan, H.; Akhtar, N.; Ali, A.

    2014-01-01

    This study was aimed to investigate the effects of cream containing Ficus carica L. fruit (Fig) extract on various skin parameters such as skin melanin, erythema, moisture content, trans-epidermal water loss and sebum. For this purpose, formulation with 4% concentrated extract of F. carica fruit and base without extract were developed. Base served as a control. Both base and formulation were applied to the cheeks of human volunteers for 8 weeks to investigate the effects on different skin parameters using non-invasive bioengineering instruments. Formulation decreased the skin melanin, trans-epidermal water loss and skin sebum significantly. Formulation increased the skin hydration significantly and insignificant effects on skin erythema. We concluded that a stable topical cream (w/o emulsion) containing F. carica fruit extract have effects on skin melanin, trans-epidermal loss, hydration values and sebum content and possibly could be used against for hyper pigmentation, acne, freckles and wrinkle. PMID:25593393

  12. In-vivo dynamic characterization of microneedle skin penetration using optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Enfield, Joey; O'Connell, Marie-Louise; Lawlor, Kate; Jonathan, Enock; O'Mahony, Conor; Leahy, Martin

    2010-07-01

    The use of microneedles as a method of circumventing the barrier properties of the stratum corneum is receiving much attention. Although skin disruption technologies and subsequent transdermal diffusion rates are being extensively studied, no accurate data on depth and closure kinetics of microneedle-induced skin pores are available, primarily due to the cumbersome techniques currently required for skin analysis. We report on the first use of optical coherence tomography technology to image microneedle penetration in real time and in vivo. We show that optical coherence tomography (OCT) can be used to painlessly measure stratum corneum and epidermis thickness, as well as microneedle penetration depth after microneedle insertion. Since OCT is a real-time, in-vivo, nondestructive technique, we also analyze skin healing characteristics and present quantitative data on micropore closure rate. Two locations (the volar forearm and dorsal aspect of the fingertip) have been assessed as suitable candidates for microneedle administration. The results illustrate the applicability of OCT analysis as a tool for microneedle-related skin characterization.

  13. In vivo Raman Confocal Spectroscopy in the Investigation of the Skin Barrier.

    PubMed

    Darlenski, Razvigor; Fluhr, Joachim W

    2016-01-01

    The epidermal barrier, predominantly attributed to the stratum corneum (SC), is the outermost part of our body that comprises multiple defensive functions against exogenous attacks and the loss of body substances, e.g. water. A novel investigative method, in vivo Raman confocal spectroscopy (RCS), is employed to study the composition of the epidermal barrier and compounds penetrating the epidermis both in a space-resolved manner. By using this method, a semiquantitative analysis of skin barrier constituents can be evaluated, namely SC lipids, natural moisturizing factor components and sweat constituents. The technique enables to examine epidermal barrier impairment in experimental settings as well as the penetration of exogenous substances into the epidermis, e.g. retinol. RCS can reveal microcompositional changes in the skin barrier as a function of age. We also review the use of RCS in studying antioxidant defense components. This chapter discusses the application of in vivo RCS in the investigation of the epidermal barrier.

  14. Rapid observation of unfixed, unstained human skin biopsy specimens with confocal microscopy and visualization

    NASA Astrophysics Data System (ADS)

    Masters, Barry R.; Aziz, David J.; Gmitro, Arthur F.; Kerr, James H.; O'Grady, Terence C.; Goldman, Leon

    1997-10-01

    The use of reflected light confocal microscopy is proposed to rapidly observe unfixed, unstained biopsy specimens of human skin. Reflected light laser scanning confocal microscopy was used to compare a freshly excised, unfixed, unstained biopsy specimen, and in vivo human skin. Optical sections from the ex vivo biopsy specimen of human skin and in vivo human skin were converted to red-green anaglyphs for 3D visualization. Contrast was derived from intrinsic differences in the scattering properties of the organelles and cells within the tissue. Individual cellular layers were observed in both tissues from the surface to the papillary dermis. Confocal microscopy of an unfixed, unstained biopsy specimen showed cells and cell nuclei of the stratum spinosum. Confocal microscopy of in vivo human skin demonstrated optical sectioning through a hair shaft on the upper hand. The combination of reflected light confocal microscopy and 3D visualization with red-green anaglyphs provides a rapid technique for observing fresh biopsies of human skin.

  15. In vitro constitution and in vivo implantation of engineered skin constructs with sweat glands.

    PubMed

    Huang, Sha; Xu, Yongan; Wu, Changhao; Sha, Deqian; Fu, Xiaobing

    2010-07-01

    Despite the rapid development of engineered skin, such skin still lacks skin appendages. Sweat glands, one of the skin appendages, play key roles in the maintenance of homeostasis and temperature regulation. In this study, we tested whether sweat glands could be integrated into engineered skin constructs to improve the quality of tissue regeneration. Using gelatin microspheres(containing epidermal growth factor [EGF]) as multifunctional vehicles, we cultured sweat gland cells (SGCs) on them and delivered SGCs-microspheres complex (SMC) into the engineered skin construct, which was created in vitro by culturing human keratinocytes on top of a fibroblast-embedded collagen-based matrix in an organotypic co-culture model. This engineered skin construct was then transplanted onto full-thickness cutaneous wounds in an athymic murine model. EGF-loaded microspheres displayed more cellular growth-promoting efficiency, and thus SMC was an available means for SGCs delivery. Constitution of the engineered skin constructs formed a skin-like pattern in vitro. Remarkably, SMC could differentiate toward a sweat gland-like structure in vitro within the hybrid matrix. Furthermore, the degree of wound healing in mice with this skin construct implantation was better than that with controls. This engineered skin construct could be used as a promising tool for regeneration of sweat glands in skin repair and a valuable engineered strategy for constitution of appendage-containing engineered skin models.

  16. In vivo localized proton spectroscopic studies of human gastrocnemius muscle

    SciTech Connect

    Narayana, P.A.; Jackson, E.F.; Hazle, J.D.; Fotedar, L.K.; Kulkarni, M.V.; Flamig, D.P.

    1988-10-01

    In vivo proton magnetic resonance spectroscopy studies of gastrocnemius muscle were performed in six normal volunteers. Both spatially resolved spectroscopy (SPARS) and stimulated echo acquisition mode (STEAM) sequences were used for volume localization. A number of water suppression sequences have been combined with these localization schemes. Among the various techniques investigated in these studies, STEAM with an inversion pulse (T1-discriminated spectrum) seems to have the best potential for in vivo localized high-resolution proton spectroscopy studies of human muscle.

  17. Spectral investigation of normal skin tissue in vivo via fiber-optical evanescent wave Fourier transform infrared (FEW-FTIR) spectroscopy

    NASA Astrophysics Data System (ADS)

    Kano, Angelique

    2001-11-01

    New applications for the Fiberoptic Evanescent Wave Fourier Transform (FEW-FTIR) method have been developed for the diagnostics of skin surfaces. Our technique allows for the detection of functional groups in the molecular structure of skin tissue noninvasively and in vivo. The FEW-FTIR spectroscopic method is direct, nondestructive, and fast. Our optical fibers for the middle infrared (MIR) range are nontoxic, nonhygroscopic, flexible, and characterized by extremely low losses. This combination of traditional FTIR spectroscopy and advanced fiber technology has enabled us to noninvasively investigate normal skin tissue in vivo in the range of 900 to 4000 cm-1. The second derivative spectra of the baseline-corrected and normalized data have been calculated to determine the peak positions. We have obtained for the first time a more detailed understanding of normal skin tissue fusing FTIR spectroscopy. Despite the complex nature of human skin tissue, the MIR spectra of normal human skin surface tissue has some basic characteristics seen in all cases. The results of our surface analysis of skin tissue are discussed in terms of spectral parameters, band assignments, and molecular structural similarities and differences. Our results have revealed that our spectral parameters can be separated into four distinct classes, providing us with a preliminary model of normal human skin tissue.

  18. Fluorescence lifetime imaging of human skin and hair

    NASA Astrophysics Data System (ADS)

    Ehlers, A.; Riemann, I.; Anhut, T.; Kaatz, M.; Elsner, P.; König, K.

    2006-02-01

    Multiphoton imaging has developed into an important technique for in-vivo research in life sciences. With the laser System DermaInspect (JenLab, Germany) laser radiation from a Ti:Sapphire laser is used to generate multiphotonabsorption deep in the human skin in vivo. The resulting autofluorescence radiation arises from endogenous fluorophores such as NAD(P)H, flavines, collagen, elastin, porphyrins und melanin. Second harmonic generation (SHG) was used to detect collagen structures in the dermal layer. Femtosecond laser multiphoton imaging offers the possibility of high resolution optical tomography of human skin as well as fluorescence lifetime imaging (FLIM) with picosecond time resolution. In this work a photon detector with ultrashort rise time of less than 30ps was applied to FLIM measurements of human skin and hair with different pigmentation. Fluorescence lifetime images of different human hair types will be discussed.

  19. Diffusion of (2-/sup 14/C)diazepam across hairless mouse skin and human skin

    SciTech Connect

    Koch, R.L.; Palicharla, P.; Groves, M.J.

    1987-05-01

    The objectives of this study were to investigate the absorption of diazepam applied topically to the hairless mouse in vivo and to determine the diffusion of diazepam across isolated hairless mouse skin and human skin. (/sup 14/C)Diazepam was readily absorbed after topical administration to the intact hairless mouse, a total of 75.8% of the /sup 14/C-label applied being recovered in urine and feces. Diazepam was found to diffuse across human and hairless mouse skin unchanged in experiments with twin-chambered diffusion cells. The variation in diffusion rate or the flux for both human and mouse tissues was greater among specimens than between duplicate or triplicate trials for a single specimen. Fluxes for mouse skin (stratum corneum, epidermis, and dermis) were greater than for human skin (stratum corneum and epidermis): 0.35-0.61 microgram/cm2/h for mouse skin vs 0.24-0.42 microgram/cm2/h for human skin. The permeability coefficients for mouse skin ranged from 1.4-2.4 X 10(-2)cm/h compared with 0.8-1.4 X 10(-2)cm/h for human skin. Although human stratum corneum is almost twice the thickness of that of the hairless mouse, the diffusion coefficients for human skin were 3-12 times greater (0.76-3.31 X 10(-6) cm2/h for human skin vs 0.12-0.27 X 10(-6) cm2/h for hairless mouse) because of a shorter lag time for diffusion across human skin. These differences between the diffusion coefficients and diffusion rates (or permeability coefficients) suggest that the presence of the dermis may present some barrier properties. In vitro the dermis may require complete saturation before the diazepam can be detected in the receiving chamber.

  20. Determination of the thickness and structure of the skin barrier by in vivo laser scanning microscopy

    NASA Astrophysics Data System (ADS)

    Lademann, J.; Richter, H.; Astner, S.; Patzelt, A.; Knorr, F.; Sterry, W.; Antoniou, Ch

    2008-04-01

    Normal skin barrier function is an essential aspect of skin homeostasis and regeneration. Dynamic inflammatory, proliferative and neoplastic skin processes such as wound healing, psoriasis and contact dermatitis are associated with a significant disruption of the skin barrier. In recent years, there has been increasing interest in evaluating cosmetic and pharmacologic products for their ability to restore these protective properties. The gold standard for characterization of barrier function has been the measurement of the transepidermal water loss, however the disadvantage of this method is its interference with several endogenous and exogenous factors such as hydration, perspiration and topically applied substances. This study was aimed to test the clinical applicability of a fluorescence confocal laser scanning microscope (LSM) for a systematic morphologic analysis of the structure, integrity and thickness of the stratum corneum in 10 otherwise healthy volunteers. The influence of skin treatment with commercial moisturizing cream on skin barrier function was evaluated in serial non-invasive examinations. Our findings showed that in vivo LSM may represent a simple and efficient method for the characterization of skin barrier properties, such as the thickness and hydration of the stratum corneum.

  1. Skin Diseases: Cross-section of human skin

    MedlinePlus

    Skip Navigation Bar Home Current Issue Past Issues Skin Diseases Cross-section of human skin Past Issues / Fall 2008 Table of Contents For ... Logical Images, Inc. I n the areas of skin health and skin diseases, the NIH's National Institute ...

  2. Remote skin tissue diagnostics in vivo by fiber optic evanescent wave Fourier transform infrared (FEW-FTIR) spectroscopy

    NASA Astrophysics Data System (ADS)

    Afanasyeva, Natalia I.; Kolyakov, Sergei F.; Butvina, Leonid N.

    1998-04-01

    The new method of fiber-optical evanescent wave Fourier transform IR (FEW-FTIR) spectroscopy has been applied to the diagnostics of normal tissue, as well as precancerous and cancerous conditions. The FEW-FTIR technique is nondestructive and sensitive to changes of vibrational spectra in the IR region, without heating and damaging human and animal skin tissue. Therefore this method and technique is an ideal diagnostic tool for tumor and cancer characterization at an early stage of development on a molecular level. The application of fiber optic technology in the middle IR region is relatively inexpensive and can be adapted easily to any commercially available tabletop FTIR spectrometers. This method of diagnostics is fast, remote, and can be applied to many fields Noninvasive medical diagnostics of skin cancer and other skin diseases in vivo, ex vivo, and in vitro allow for the development convenient, remote clinical applications in dermatology and related fields. The spectral variations from normal to pathological skin tissue and environmental influence on skin have been measured and assigned in the regions of 850-4000 cm-1. The lipid structure changes are discussed. We are able to develop the spectral histopathology as a fast and informative tool of analysis.

  3. Genetic identification of C-fibers that detect massage-like stroking of hairy skin in vivo

    PubMed Central

    Vrontou, Sophia; Wong, Allan M.; Rau, Kristofer K.; Koerber, H. Richard; Anderson, David J.

    2012-01-01

    Stroking of the skin produces pleasant sensations that can occur during social interactions with conspecifics, such as grooming1. Despite numerous physiological studies (reviewed in ref. 2), molecularly defined sensory neurons that detect pleasant stroking of hairy skin3,4 in vivo have not been reported. Previously, we identified a rare population of unmyelinated sensory neurons that express the G protein-coupled receptor (GPCR) MrgprB45,6. These neurons exclusively innervate hairy skin with large terminal arborizations7 that resemble the receptive fields of C-tactile (CT) afferents in humans8. Unlike other molecularly defined mechanosensory C-fiber subtypes9,10, MrgprB4+ neurons could not be detectably activated by sensory stimulation of the skin ex vivo. Therefore, we developed a preparation for calcium imaging in their spinal projections during stimulation of the periphery in intact animals. MrgprB4+ neurons were activated by massage-like stroking of hairy skin, but not by noxious punctate mechanical stimulation. By contrast, a different population of C-fibers expressing MrgprD11 was activated by pinching but not by stroking, consistent with previous physiological and behavioral data10,12. Pharmacogenetic activation of MrgprB4- expressing neurons in freely behaving animals promoted conditioned place preference13, suggesting that such activation is positively reinforcing and/or anxiolytic. These data open the way to understanding the function of MrgprB4 neurons during natural behaviors, and provide a general approach to functionally characterizing genetically identified subsets of somatosensory neurons in vivo. PMID:23364746

  4. Diet-induced obesity skin changes monitored by in vivo SHG and ex vivo CARS microscopy

    PubMed Central

    Haluszka, Dóra; Lőrincz, Kende; Kiss, Norbert; Szipőcs, Róbert; Kuroli, Enikő; Gyöngyösi, Nóra; Wikonkál, Norbert M.

    2016-01-01

    Obesity related metabolic syndrome and type 2 diabetes have severe consequences on our skin. Latest developments in nonlinear microscopy allow the use of noninvasive, label free imaging methods, such as second harmonic generation (SHG) and coherent anti-Stokes Raman scattering (CARS), for early diagnosis of metabolic syndrome-related skin complications by 3D imaging of the skin and the connective tissue. Our aim was to study effects of various types of diet-induced obesity in mice using these methods. We examined mice on different diets for 32 weeks. The collagen morphology was evaluated four times in vivo by SHG microscopy, and adipocytes were examined once at the end of experiment by ex vivo CARS method. A strong correlation was found between the body weight and the adipocyte size, while we found that the SHG intensity of dermal collagen reduces considerably with increasing body weight. Obese mice on high-fat diet showed worse results than those on high-fat - high-fructose diet. Animals on high-fructose diet did not gain more weight than those on ordinary diet despite of the increased calorie intake, but their collagen damage was nonetheless significant. Obesity and high sugar intake damages the skin, mainly the dermal connective tissue and subcutaneous adipose tissue, which efficiently can be monitored by in vivo SHG and ex vivo CARS microscopy. PMID:27895989

  5. Humanized in vivo Model for Autoimmune Diabetes

    DTIC Science & Technology

    2010-05-07

    complexes in the thymus. As T cell CD4 avidity interaction with the 2 domain of the MHC class II has been shown to contribute positively to thymic T...mice (DR4) were generated as previously de- scribed [ 2 ]. These C57BL/6 I-Abo/o mice express a human- mouse chimeric class II molecule in which the TcR...transgenic for the type 1 diabetes- associated human MHC class II allele, DRB1*0401. J Clin Invest 1996;98:2597e603. [9] Kim J, Richter W, Aanstoot HJ

  6. In vivo skin chromophore mapping using a multimode imaging dermoscope (SkinSpec)

    NASA Astrophysics Data System (ADS)

    MacKinnon, Nicholas; Vasefi, Fartash; Gussakovsky, Eugene; Bearman, Gregory; Chave, Robert; Farkas, Daniel L.

    2013-02-01

    We introduce a multimode dermoscope (SkinSpectTM) we developed for early detection of melanoma by combining fluorescence, polarization and hyperspectral imaging. Acquired reflection image datacubes were input to a wavelength-dependent linear model to extract the relative contributions of skin chromophores at every pixel. The oxy-hemoglobin, deoxy hemoglobin, melanin concentrations, and hemoglobin oxygen saturation by the single step linear least square fitting and Kubelka-Munk tissue model using cross polarization data cubes were presented. The comprehensive data obtained by SkinSpect can be utilized to improve the accuracy of skin chromophore decomposition algorithm with less computation cost. As an example in this work, the deoxy-hemoglobin over-estimation error in highly pigmented lesion due to melanin and deoxy hemoglobin spectral cross talk were analyzed and corrected using two-step linear least square fitting procedure at different wavelength ranges. The proposed method also tested in skin with underlying vein area for validating the proof of concept.

  7. Histological study of subcutaneous fat at NIR laser treatment of the rat skin in vivo

    NASA Astrophysics Data System (ADS)

    Yanina, I. Y.; Svenskaya, Yu. I.; Navolokin, N. A.; Matveeva, O. V.; Bucharskaya, A. B.; Maslyakova, G. N.; Gorin, D. A.; Sukhorukov, G. B.; Tuchin, V. V.

    2015-07-01

    The goal of this work is to quantify impact of in vivo photochemical treatment using indocyanine green (ICG) or encapsulated ICG and NIR laser irradiation through skin of rat with obesity by the follow up tissue sampling and histochemistry. After 1 hour elapsed since 1-min light exposure samples of rat skin with subcutaneous tissue of thickness of 1.5-2.5 mm were taken by surgery from rats within marked 4-zones of the skin site. For hematoxylin-eosin histological examination of excised tissue samples, fixation was carried out by 10%-formaldehyde solution. For ICG and encapsulated ICG subcutaneous injection and subsequent 1-min diode laser irradiation with power density of 8 W/cm2, different necrotic regions with lipolysis of subcutaneous fat were observed. The obtained data can be used for safe layer-by-layer laser treatment of obesity and cellulite.

  8. Characterization of pigmented dermo-epidermal skin substitutes in a long-term in vivo assay.

    PubMed

    Böttcher-Haberzeth, Sophie; Biedermann, Thomas; Klar, Agnieszka S; Widmer, Daniel S; Neuhaus, Kathrin; Schiestl, Clemens; Meuli, Martin; Reichmann, Ernst

    2015-01-01

    In our laboratory, we have been using human pigmented dermo-epidermal skin substitutes for short-term experiments since several years. Little is known, however, about the long-term biology of such constructs after transplantation. We constructed human, melanocyte-containing dermo-epidermal skin substitutes of different (light and dark) pigmentation types and studied them in a long-term animal experiment. Developmental and maturational stages of the epidermal and dermal compartment as well as signs of homoeostasis were analysed 15 weeks after transplantation. Keratinocytes, melanocytes and fibroblasts from human skin biopsies were isolated and assembled into dermo-epidermal skin substitutes. These were transplanted onto immuno-incompetent rats and investigated 15 weeks after transplantation. Chromameter evaluation showed a consistent skin colour between 3 and 4 months after transplantation. Melanocytes resided in the epidermal basal layer in physiological numbers and melanin accumulated in keratinocytes in a supranuclear position. Skin substitutes showed a mature epidermis in a homoeostatic state and the presence of dermal components such as Fibrillin and Tropoelastin suggested advanced maturation. Overall, pigmented dermo-epidermal skin substitutes show a promising development towards achieving near-normal skin characteristics and epidermal and dermal tissue homoeostasis. In particular, melanocytes function correctly over several months whilst remaining in a physiological, epidermal position and yield a pigmentation resembling original donor skin colour.

  9. In-vivo differentiation of photo-aged epidermis skin by texture-based classification

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaoman; Weng, Cuncheng; Yu, Biying; Li, Hui

    2014-11-01

    Two sets of in vivo female cheek skin epidermis images were analyzed through gray level co-occurrence matrix (GLCM) and fast fourier transform (FFT). One set was derived from women in their 20s and the other from women more than 60 years of age. GLCM was used to evaluate the texture features of the regions of interest within the cheek epidermis, and texture classification was subsequently performed. During texture classification, 25 images (320×240 pixels) in each age set were randomly selected. Three texture features, i.e., energy, contrast, and correlation, were obtained from the skin images and analyzed at four orientations (0°, 45°,90°, and 135°), accompanied by different distances between two pixels. The textures of the different aging skins were characterized by FFT, which provides the dermatoglyph orientation index. The differences in the textures between the young and old skin samples can be well described by the FFT dermatoglyph orientation index. The texture features varied among the different aging skins, which provide a versatile platform for differentiating the statuses of aging skins.

  10. The human parental brain: in vivo neuroimaging.

    PubMed

    Swain, James E

    2011-07-01

    Interacting parenting thoughts and behaviors, supported by key brain circuits, critically shape human infants' current and future behavior. Indeed, the parent-infant relationship provides infants with their first social environment, forming templates for what they can expect from others, how to interact with them and ultimately how they go on to themselves to be parents. This review concentrates on magnetic resonance imaging experiments of the human parent brain, which link brain physiology with parental thoughts and behaviors. After reviewing brain imaging techniques, certain social cognitive and affective concepts are reviewed, including empathy and trust-likely critical to parenting. Following that is a thorough study-by-study review of the state-of-the-art with respect to human neuroimaging studies of the parental brain-from parent brain responses to salient infant stimuli, including emotionally charged baby cries and brief visual stimuli to the latest structural brain studies. Taken together, this research suggests that networks of highly conserved hypothalamic-midbrain-limbic-paralimbic-cortical circuits act in concert to support parental brain responses to infants, including circuits for limbic emotion response and regulation. Thus, a model is presented in which infant stimuli activate sensory analysis brain regions, affect corticolimbic limbic circuits that regulate emotional response, motivation and reward related to their infant, ultimately organizing parenting impulses, thoughts and emotions into coordinated behaviors as a map for future studies. Finally, future directions towards integrated understanding of the brain basis of human parenting are outlined with profound implications for understanding and contributing to long term parent and infant mental health.

  11. Homogeneous transport in a heterogeneous membrane: water diffusion across human stratum corneum in vivo.

    PubMed Central

    Kalia, Y N; Pirot, F; Guy, R H

    1996-01-01

    The objective of this study was to determine whether a structurally heterogeneous biomembrane, human stratum corneum (SC), behaved as a homogeneous barrier to water transport. The question is relevant because the principal function of the SC in vivo is to provide a barrier to the insensible loss of tissue water across the skin. Impedance spectra (IS) of the skin and measurements of the rate of transepidermal water loss (TEWL) were recorded sequentially in vivo in human subjects as layers of the SC were progressively removed by the serial application of adhesive tape strips. The low-frequency (< or = 100 rad s-1) impedance of skin was much more significantly affected by tape stripping than the higher frequency values; removal of the outermost SC layer had the largest effect. In contrast, TEWL changed little as the outer SC layers were stripped off, but increased dramatically when 6-8 microns of the tissue had been removed. It follows that the two noninvasive techniques probe SC barrier integrity in somewhat different ways. After SC removal, recovery of barrier function, as assessed by increasing values of the low-frequency impedance, apparently proceeded faster than TEWL decreased to the prestripping control. The variation of TEWL as a function of SC removal behaved in a manner entirely consistent with a homogeneous barrier, thereby permitting the apparent SC diffusivity of water to be found. Skin impedance (low frequency) was correlated with the relative concentration of water within the SC, thus providing an in vivo probe for skin hydration. Finally, the SC permeability coefficient to water, as a function of SC thickness, was calculated and correlated with the corresponding values of skin admittance derived from IS. PMID:8913606

  12. Tryptophan hydroxylase expression in human skin cells.

    PubMed

    Slominski, Andrzej; Pisarchik, Alexander; Johansson, Olle; Jing, Chen; Semak, Igor; Slugocki, George; Wortsman, Jacobo

    2003-10-15

    We attempted to further characterize cutaneous serotoninergic and melatoninergic pathways evaluating the key biosynthetic enzyme tryptophan hydroxylase (TPH). There was wide expression of TPH mRNA in whole human skin, cultured melanocytes and melanoma cells, dermal fibroblasts, squamous cell carcinoma cells and keratinocytes. Gene expression was associated with detection of TPH immunoreactive species by Western blotting. Characterization of the TPH immunoreactive species performed with two different antibodies showed expression of the expected protein (55-60 kDa), and of forms with higher and lower molecular weights. This pattern of broad spectrum of TPH expression including presumed degradation products suggests rapid turnover of the enzyme, as previously reported in mastocytoma cells. RP-HPLC of skin extracts showed fluorescent species with the retention time of serotonin and N-acetylserotonin. Immunocytochemistry performed in skin biopsies localized TPH immunoreactivity to normal and malignant melanocytes. We conclude that while the TPH mRNA and protein are widely expressed in cultured normal and pathological epidermal and dermal skin cells, in vivo TPH expression is predominantly restricted to cells of melanocytic origin.

  13. Quantitative analysis of intrinsic skin aging in dermal papillae by in vivo harmonic generation microscopy

    PubMed Central

    Liao, Yi-Hua; Kuo, Wei-Cheng; Chou, Sin-Yo; Tsai, Cheng-Shiun; Lin, Guan-Liang; Tsai, Ming-Rung; Shih, Yuan-Ta; Lee, Gwo-Giun; Sun, Chi-Kuang

    2014-01-01

    Chronological skin aging is associated with flattening of the dermal-epidermal junction (DEJ), but to date no quantitative analysis focusing on the aging changes in the dermal papillae (DP) has been performed. The aim of the study is to determine the architectural changes and the collagen density related to chronological aging in the dermal papilla zone (DPZ) by in vivo harmonic generation microscopy (HGM) with a sub-femtoliter spatial resolution. We recruited 48 Asian subjects and obtained in vivo images on the sun-protected volar forearm. Six parameters were defined to quantify 3D morphological changes of the DPZ, which we analyzed both manually and computationally to study their correlation with age. The depth of DPZ, the average height of isolated DP, and the 3D interdigitation index decreased with age, while DP number density, DP volume, and the collagen density in DP remained constant over time. In vivo high-resolution HGM technology has uncovered chronological aging-related variations in DP, and sheds light on real-time quantitative skin fragility assessment and disease diagnostics based on collagen density and morphology. PMID:25401037

  14. Imaging immune response of skin mast cells in vivo with two-photon microscopy

    NASA Astrophysics Data System (ADS)

    Li, Chunqiang; Pastila, Riikka K.; Lin, Charles P.

    2012-02-01

    Intravital multiphoton microscopy has provided insightful information of the dynamic process of immune cells in vivo. However, the use of exogenous labeling agents limits its applications. There is no method to perform functional imaging of mast cells, a population of innate tissue-resident immune cells. Mast cells are widely recognized as the effector cells in allergy. Recently their roles as immunoregulatory cells in certain innate and adaptive immune responses are being actively investigated. Here we report in vivo mouse skin mast cells imaging with two-photon microscopy using endogenous tryptophan as the fluorophore. We studied the following processes. 1) Mast cells degranulation, the first step in the mast cell activation process in which the granules are released into peripheral tissue to trigger downstream reactions. 2) Mast cell reconstitution, a procedure commonly used to study mast cells functioning by comparing the data from wild type mice, mast cell-deficient mice, and mast-cell deficient mice reconstituted with bone marrow-derived mast cells (BMMCs). Imaging the BMMCs engraftment in tissue reveals the mast cells development and the efficiency of BMMCs reconstitution. We observed the reconstitution process for 6 weeks in the ear skin of mast cell-deficient Kit wsh/ w-sh mice by two-photon imaging. Our finding is the first instance of imaging mast cells in vivo with endogenous contrast.

  15. In vivo interstitial glucose characterization and monitoring in the skin by ATR-FTIR spectroscopy

    NASA Astrophysics Data System (ADS)

    Skrebova Eikje, Natalja

    2011-03-01

    Successful development of real-time non-invasive glucose monitoring would represent a major advancement not only in the treatment and management of patients with diabetes mellitus and carbohydrate metabolism disorders, but also for understanding in those biochemical, metabolic and (patho-)physiological processes of glucose at the molecular level in vivo. Here, ATR-FTIR spectroscopy technique has been challenged not only for in vivo measurement of interstitial glucose levels, but also for their non-invasive molecular qualitative and quantitative comparative characterization in the skin tissue. The results, based on calculated mean values of determined 5 glucose-specific peaks in the glucose-related 1000-1160 cm-1 region, showed intra- and inter-subject differences in interstitial glucose activity levels with their changes at different times and doses of OGTT, while raising questions about the relationships between interstitial and blood glucose levels. In conclusion, the introduction of ATR-FTIR spectroscopy technique has opened up an access to the interstitial fluid space in the skin tissue for interstitial glucose characterization and monitoring in vivo. Though interstitial versus blood glucose monitoring has different characteristics, it can be argued that accurate and precise measurements of interstitial glucose levels may be more important clinically.

  16. Resonance Raman spectroscopic evaluation of skin carotenoids as a biomarker of carotenoid status for human studies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Resonance Raman Spectroscopy (RRS) is a non-invasive method that has been developed to assess carotenoid status in human tissues including human skin in vivo. Skin carotenoid status, as assessed by RRS, has been suggested as a promising biomarker for use in human studies. This manuscript describes...

  17. Characterization of a new MOSFET detector configuration for in vivo skin dosimetry

    SciTech Connect

    Scalchi, Paolo; Francescon, Paolo; Rajaguru, Priyadarshini

    2005-06-15

    The dose released to the patient skin during a radiotherapy treatment is important when the skin is an organ at risk, or on the contrary, is included in the target volume. Since most treatment planning programs do not predict dose within several millimeters of the body surface, it is important to have a method to verify the skin dose for the patient who is undergoing radiotherapy. A special type of metal oxide semiconductors field-effect transistors (MOSFET) was developed to perform in vivo skin dosimetry for radiotherapy treatments. Water-equivalent depth (WED), both manufacturing and sensor reproducibility, dependence on both field size and angulation of the sensor were investigated using 6 MV photon beams. Patient skin dosimetries were performed during 6 MV total body irradiations (TBI). The resulting WEDs ranged from 0.04 and 0.15 mm (0.09 mm on average). The reproducibility of the sensor response, for doses of 50 cGy, was within {+-}2% (maximum deviation) and improves with increasing sensitivity or dose level. As to the manufacturing reproducibility, it was found to be {+-}0.055 mm. No WED dependence on the field size was verified, but possible variations of this quantity with the field size could be hidden by the assessment uncertainty. The angular dependence, for both phantom-surface and in-air setups, when referred to the mean response, is within {+-}27% until 80 deg. rotations. The results of the performed patient skin dosimetries showed that, normally, our TBI setup was suitable to give skin the prescribed dose, but, for some cases, interventions were necessary: as a consequence the TBI setup was corrected. The water-equivalent depth is, on average, less than the thinnest thermoluminescent dosimeters (TLD). In addition, when compared with TLDs, the skin MOSFETs have significant advantages, like immediate both readout and reuse, as well as the permanent storage of dose. These sensors are also waterproof. The in vivo dosimetries performed prove the

  18. In vivo comparative documentation of skin hydration by confocal Raman microscopy, SkinSensor, Skicon, and NovaMeter

    NASA Astrophysics Data System (ADS)

    Zhang, Guojin; Papillon, Aline; Ruvolo, Eduardo, Jr.; Bargo, Paulo R.; Kollias, Nikiforos

    2010-02-01

    The stratum corneum provides a vital physical barrier that protects against external insults and excessive internal water loss. Water activity is thought as a key factor to maintain proper skin barrier integrity via regulating enzyme activities and lipid phase behavior. Consequently, maintenance of an optimal hydration level in SC becomes an important clinical and cosmetic concern. The objective methods to assess SC hydration are based on either electrical or optical measurements. Electrical techniques used in the current study include high frequency conductance (Skicon), impedance (Nova DPM) and DC I-V curve (Skinsensor). Confocal Raman Microscopy was utilized to document water profile versus depth, and this technique is based on inelastic scattering of monochromatic light from different chemical species of skin. Water patches were applied on the 14 subjects' forearm for 20 minutes and 1.5 hrs. Skin hydration levels for individuals were documented by utilizing the mentioned above instruments in vivo. Results show that patterns of water profiles upon the hydration are significantly different among the individuals and these differences may be related to skin barrier function integrity. The intrinsic water content and water absorption upon the hydration were summed corresponding to different depths (3 μm and 15 μm) from the data obtained by confocal Raman microscopy. These results were correlated to the readings from electrical approaches. Superficial (3 μm) but not deeper layer (15 μm) water contents correlated well with the readings from SkinSensor. Neither depth measurements correlate well with the Skicon. There is strong correlation between the data acquired with Skicon and SkinSensor.

  19. Sexual hormones in human skin.

    PubMed

    Zouboulis, C C; Chen, W-C; Thornton, M J; Qin, K; Rosenfield, R

    2007-02-01

    The skin locally synthesizes significant amounts of sexual hormones with intracrine or paracrine actions. The local level of each sexual steroid depends upon the expression of each of the androgen- and estrogen-synthesizing enzymes in each cell type, with sebaceous glands and sweat glands being the major contributors. Sebocytes express very little of the key enzyme, cytochrome P450c17, necessary for synthesis of the androgenic prohormones dehydroepiandrosterone and androstenedione, however, these prohormones can be converted by sebocytes and sweat glands, and probably also by dermal papilla cells, into more potent androgens like testosterone and dihydrotestosterone. Five major enzymes are involved in the activation and deactivation of androgens in skin. Androgens affect several functions of human skin, such as sebaceous gland growth and differentiation, hair growth, epidermal barrier homeostasis and wound healing. Their effects are mediated by binding to the nuclear androgen receptor. Changes of isoenzyme and/or androgen receptor levels may have important implications in the development of hyperandrogenism and the associated skin diseases such as acne, seborrhoea, hirsutism and androgenetic alopecia. On the other hand, estrogens have been implicated in skin aging, pigmentation, hair growth, sebum production and skin cancer. Estrogens exert their actions through intracellular receptors or via cell surface receptors, which activate specific second messenger signaling pathways. Recent studies suggest specific site-related distribution of ERalpha and ERbeta in human skin. In contrast, progestins play no role in the pathogenesis of skin disorders. However, they play a major role in the treatment of hirsutism and acne vulgaris, where they are prescribed as components of estrogen-progestin combination pills and as anti-androgens. These combinations enhance gonadotropin suppression of ovarian androgen production. Estrogen-progestin treatment can reduce the need for shaving

  20. In-vivo monitoring rat skin wound healing using nonlinear optical microscopy

    NASA Astrophysics Data System (ADS)

    Chen, Jing; Guo, Chungen; Zhang, Fan; Xu, Yahao; Zhu, Xiaoqin; Xiong, Shuyuan; Chen, Jianxin

    2014-11-01

    Nonlinear optical microscopy (NLOM) was employed for imaging and evaluating the wound healing process on rat skin in vivo. From the high-resolution nonlinear optical images, the morphology and distribution of specific biological markers in cutaneous wound healing such as fibrin clot, collagens, blood capillaries, and hairs were clearly observed at 1, 5 and 14 days post injury. We found that the disordered collagen in the fibrin clot at day 1 was replaced by regenerative collagen at day 5. By day 14, the thick collagen with well-network appeared at the original margin of the wound. These findings suggested that NLOM is ideal for noninvasively monitoring the progress of wound healing in vivo.

  1. In vivo determination of optical properties and fluorophore characteristics of non-melanoma skin cancer

    NASA Astrophysics Data System (ADS)

    Rajaram, Narasimhan; Kovacic, Dianne; Migden, Michael F.; Reichenberg, Jason S.; Nguyen, Tri H.; Tunnell, James W.

    2009-02-01

    Diffuse optical spectroscopy (DOS) and laser-induced fluorescence (LIF) techniques have widely been used as noninvasive tools for early cancer detection in several organs including the cervix, oral cavity and gastrointestinal tract. Using a combined DOS/LIF approach, one can simultaneously measure the morphology and biochemical composition of tissue and use these features to diagnose malignancy. We report for the first time to our knowledge both the optical properties and native fluorophore characteristics of non-melanoma skin cancer in the UV-visible range. We collected in vivo diffuse reflectance and intrinsic fluorescence measurements from 44 skin lesions on 37 patients. The skin sites were further categorized into three groups of non-melanoma skin cancer according to histopathology: 1) pre-cancerous actinic keratosis 2) malignant squamous cell carcinoma (SCC) and 3) basal cell carcinoma (BCC). We used a custom-built probe-based clinical system that collects both white light reflectance and laser-induced fluorescence in the wavelength range of 350-700 nm. We extracted the blood volume fraction, oxygen saturation, blood vessel size, tissue microarchitecture and melanin content from diffuse reflectance measurements. In addition, we determined the native fluorophore contributions of NADH, collagen and FAD from laser-induced fluorescence for all groups. The scattering from tissue decreased with progression from clinically normal to precancerous actinic keratosis to malignant SCC. A similar trend was observed for clinically normal skin and malignant BCC. Statistically significant differences were observed in the collagen contributions, which were lower in malignant SCC and BCC as compared to normal skin. Our data demonstrates that the mean optical properties and fluorophore contributions of normal, benign and malignant nonmelanoma cancers are significantly different from each other and can potentially be used as biomarkers for the early detection of skin cancer.

  2. Solvent effects in permeation assessed in vivo by skin surface biopsy

    PubMed Central

    Rosado, Catarina; Rodrigues, Luis Monteiro

    2003-01-01

    Background Transdermal drug delivery has become an important means of drug administration. It presents numerous advantages but it is still limited by the small number of drugs with a suitable profile. The use of solvents that affect the skin barrier function is one of the classic strategies of penetration enhancement. Some of these solvents have well characterised actions on the stratum corneum, but the majority are still selected using empirical criteria. The objective of this work was to conduct a systematic study on the ability to affect skin permeation of solvents commonly used in transdermal formulations. An innovative methodology in this area was employed, consisting of the combination of skin surface biopsy with colorimetry. Methods The study compared in vivo differences in the permeation of a hydrophilic (methylene blue) and a lipophilic (Sudan III) dye, after treatment of the skin with different vehicles. Consecutive skin surface biopsies of each site were taken and the cumulative amounts of the dyes in the stripped stratum corneum were measured by reflectance colourimetry. Results Results indicate that the amount of methylene blue present in the stratum corneum varied significantly with different skin pre-treatments. Some solvents provided a 1.5 fold penetration enhancement but others decreased by almost half the permeation of the dye. The permeation of Sudan III was less significantly affected by solvent pre-treatment. Conclusions This study has only superficially explored the potential of the combination of skin surface biopsy and colourimetry, but the encouraging results obtained confirm that the methodology can be extended to the study of more complex formulations. PMID:14680512

  3. In-vivo fluorescence detection and imaging of porphyrin-producing bacteria in the human skin and in the oral cavity for diagnosis of acne vulgaris, caries, and squamous cell carcinoma

    NASA Astrophysics Data System (ADS)

    Koenig, Karsten; Schneckenburger, Herbert; Hemmer, Joerg; Tromberg, Bruce J.; Steiner, Rudolf W.

    1994-05-01

    Certain bacteria are able to synthesize metal-free fluorescent porphyrins and can therefore be detected by sensitive autofluorescence measurements in the red spectral region. The porphyrin-producing bacterium Propionibacterium acnes, which is involved in the pathogenesis of acne vulgaris, was localized in human skin. Spectrally resolved fluorescence images of bacteria distribution in the face were obtained by a slow-scan CCD camera combined with a tunable liquid crystal filter. The structured autofluorescence of dental caries and dental plaque in the red is caused by oral bacteria, like Bacteroides or Actinomyces odontolyticus. `Caries images' were created by time-gated imaging in the ns-region after ultrashort laser excitation. Time-gated measurements allow the suppression of backscattered light and non-porphyrin autofluorescence. Biopsies of oral squamous cell carcinoma exhibited red autofluorescence in necrotic regions and high concentrations of the porphyrin-producing bacterium Pseudomonas aerigunosa. These studies suggest that the temporal and spectral characteristics of bacterial autofluorescence can be used in the diagnosis and treatment of a variety of diseases.

  4. In vivo characterization of hair and skin derived carbon quantum dots with high quantum yield as long-term bioprobes in zebrafish

    NASA Astrophysics Data System (ADS)

    Zhang, Jing-Hui; Niu, Aping; Li, Jing; Fu, Jian-Wei; Xu, Qun; Pei, De-Sheng

    2016-11-01

    Carbon quantum dots (CDs) were widely investigated because of their tunable fluorescence properties and low toxicity. However, so far there have been no reports on in vivo functional studies of hair and skin derived CDs. Here, hair derived CDs (HCDs) and skin derived CDs (SCDs) were produced by using human hair and pig skin as precursors. The quantum yields (QYs) of HCDs and SCDs were quite high, compared to citric acid derived CDs (CCDs). HCDs and SCDs possess optimal photostability, hypotoxicity and biocompatibility in zebrafish, indicating that HCDs and SCDs possess the capacity of being used as fluorescence probes for in vivo biological imaging. The long-time observation for fluorescence alternation of CDs in zebrafish and the quenching assay of CDs by ATP, NADH and Fe3+ ions demonstrated that the decaying process of CDs in vivo might be induced by the synergistic effect of the metabolism process. All results indicated that large batches and high QYs of CDs can be acquired by employing natural and nontoxic hair and skin as precursors. To our knowledge, this is the first time to report SCDs, in vivo comparative studies of HCDs, SCDs and CCDs as bioprobes, and explore their mechanism of photostability in zebrafish.

  5. In vivo characterization of hair and skin derived carbon quantum dots with high quantum yield as long-term bioprobes in zebrafish

    PubMed Central

    Zhang, Jing-Hui; Niu, Aping; Li, Jing; Fu, Jian-Wei; Xu, Qun; Pei, De-Sheng

    2016-01-01

    Carbon quantum dots (CDs) were widely investigated because of their tunable fluorescence properties and low toxicity. However, so far there have been no reports on in vivo functional studies of hair and skin derived CDs. Here, hair derived CDs (HCDs) and skin derived CDs (SCDs) were produced by using human hair and pig skin as precursors. The quantum yields (QYs) of HCDs and SCDs were quite high, compared to citric acid derived CDs (CCDs). HCDs and SCDs possess optimal photostability, hypotoxicity and biocompatibility in zebrafish, indicating that HCDs and SCDs possess the capacity of being used as fluorescence probes for in vivo biological imaging. The long-time observation for fluorescence alternation of CDs in zebrafish and the quenching assay of CDs by ATP, NADH and Fe3+ ions demonstrated that the decaying process of CDs in vivo might be induced by the synergistic effect of the metabolism process. All results indicated that large batches and high QYs of CDs can be acquired by employing natural and nontoxic hair and skin as precursors. To our knowledge, this is the first time to report SCDs, in vivo comparative studies of HCDs, SCDs and CCDs as bioprobes, and explore their mechanism of photostability in zebrafish. PMID:27886267

  6. Infrared neural stimulation of human spinal nerve roots in vivo

    PubMed Central

    Cayce, Jonathan M.; Wells, Jonathon D.; Malphrus, Jonathan D.; Kao, Chris; Thomsen, Sharon; Tulipan, Noel B.; Konrad, Peter E.; Jansen, E. Duco; Mahadevan-Jansen, Anita

    2015-01-01

    Abstract. Infrared neural stimulation (INS) is a neurostimulation modality that uses pulsed infrared light to evoke artifact-free, spatially precise neural activity with a noncontact interface; however, the technique has not been demonstrated in humans. The objective of this study is to demonstrate the safety and efficacy of INS in humans in vivo. The feasibility of INS in humans was assessed in patients (n=7) undergoing selective dorsal root rhizotomy, where hyperactive dorsal roots, identified for transection, were stimulated in vivo with INS on two to three sites per nerve with electromyogram recordings acquired throughout the stimulation. The stimulated dorsal root was removed and histology was performed to determine thermal damage thresholds of INS. Threshold activation of human dorsal rootlets occurred in 63% of nerves for radiant exposures between 0.53 and 1.23  J/cm2. In all cases, only one or two monitored muscle groups were activated from INS stimulation of a hyperactive spinal root identified by electrical stimulation. Thermal damage was first noted at 1.09  J/cm2 and a 2∶1 safety ratio was identified. These findings demonstrate the success of INS as a fresh approach for activating human nerves in vivo and providing the necessary safety data needed to pursue clinically driven therapeutic and diagnostic applications of INS in humans. PMID:26157986

  7. Infrared neural stimulation of human spinal nerve roots in vivo.

    PubMed

    Cayce, Jonathan M; Wells, Jonathon D; Malphrus, Jonathan D; Kao, Chris; Thomsen, Sharon; Tulipan, Noel B; Konrad, Peter E; Jansen, E Duco; Mahadevan-Jansen, Anita

    2015-01-01

    Infrared neural stimulation (INS) is a neurostimulation modality that uses pulsed infrared light to evoke artifact-free, spatially precise neural activity with a noncontact interface; however, the technique has not been demonstrated in humans. The objective of this study is to demonstrate the safety and efficacy of INS in humans in vivo. The feasibility of INS in humans was assessed in patients ([Formula: see text]) undergoing selective dorsal root rhizotomy, where hyperactive dorsal roots, identified for transection, were stimulated in vivo with INS on two to three sites per nerve with electromyogram recordings acquired throughout the stimulation. The stimulated dorsal root was removed and histology was performed to determine thermal damage thresholds of INS. Threshold activation of human dorsal rootlets occurred in 63% of nerves for radiant exposures between 0.53 and [Formula: see text]. In all cases, only one or two monitored muscle groups were activated from INS stimulation of a hyperactive spinal root identified by electrical stimulation. Thermal damage was first noted at [Formula: see text] and a [Formula: see text] safety ratio was identified. These findings demonstrate the success of INS as a fresh approach for activating human nerves in vivo and providing the necessary safety data needed to pursue clinically driven therapeutic and diagnostic applications of INS in humans.

  8. Clinical study of noninvasive in vivo melanoma and nonmelanoma skin cancers using multimodal spectral diagnosis

    PubMed Central

    Lim, Liang; Nichols, Brandon; Migden, Michael R.; Rajaram, Narasimhan; Reichenberg, Jason S.; Markey, Mia K.; Ross, Merrick I.; Tunnell, James W.

    2014-01-01

    Abstract. The goal of this study was to determine the diagnostic capability of a multimodal spectral diagnosis (SD) for in vivo noninvasive disease diagnosis of melanoma and nonmelanoma skin cancers. We acquired reflectance, fluorescence, and Raman spectra from 137 lesions in 76 patients using custom-built optical fiber-based clinical systems. Biopsies of lesions were classified using standard histopathology as malignant melanoma (MM), nonmelanoma pigmented lesion (PL), basal cell carcinoma (BCC), actinic keratosis (AK), and squamous cell carcinoma (SCC). Spectral data were analyzed using principal component analysis. Using multiple diagnostically relevant principal components, we built leave-one-out logistic regression classifiers. Classification results were compared with histopathology of the lesion. Sensitivity/specificity for classifying MM versus PL (12 versus 17 lesions) was 100%/100%, for SCC and BCC versus AK (57 versus 14 lesions) was 95%/71%, and for AK and SCC and BCC versus normal skin (71 versus 71 lesions) was 90%/85%. The best classification for nonmelanoma skin cancers required multiple modalities; however, the best melanoma classification occurred with Raman spectroscopy alone. The high diagnostic accuracy for classifying both melanoma and nonmelanoma skin cancer lesions demonstrates the potential for SD as a clinical diagnostic device. PMID:25375350

  9. Glabridin nanosuspension for enhanced skin penetration: formulation optimization, in vitro and in vivo evaluation.

    PubMed

    Wang, W P; Hul, J; Sui, H; Zhao, Y S; Feng, J; Liu, C

    2016-05-01

    Glabridin, a polyphenolic flavonoid from licorice, has inspired great interest for its antioxidant, anti-inflammatory and skin-lightening activities. However, low water solubility and poor stability of glabridin impedes its topical application in cosmetic products and therapies of dermal diseases. The purpose of this study was to develop a nanosuspension formulation of glabridin to improve its skin permeation. Glabridin nanosuspensions were prepared using anti-solvent precipitation-homogenization method, and Box-Behnken design was adopted to investigate the effects of crucial formulation variables on particle size and to optimize the nanosuspension formulation. The optimal formulation consisted of 0.25% glabridin, 0.47% Poloxamer 188 and 0.11% Polyvinylpyrrolidone K30, and the obtained nanosuspension showed an average particle size of 149.2 nm with a polydispersity index of 0.254. Furthermore, the nanosuspension exhibited significantly enhanced drug permeation flux of glabridin through rat skin with no lag phase both in vitro and in vivo, compared to the coarse suspension and physical mixture. The glabridin nanosuspension showed no significant particle aggregates and a drug loss of 5.46% after storage for 3 months at room temperature. With its enhanced skin penetration, the nanosuspension might be a more preferable formulation for topical administration of poorly soluble glabridin.

  10. A useful way to develop effective in vivo skin optical clearing agents.

    PubMed

    Shi, Rui; Guo, Li; Zhang, Chao; Feng, Wei; Li, Peng; Ding, Zhihua; Zhu, Dan

    2016-12-23

    Skin optical clearing has shown tremendous potential in improving various optical imaging performances, but there is some certain blindness in screening out high-efficiency in vivo optical clearing methods. In this work, three optical clearing agents: sucrose (Suc), fructose (Fruc) and PEG-400 (PEG), and two chemical penetration enhancers: propylene glycol (PG) and thiazone (Thiaz) were used. PEG was firstly mixed with the two penetration enhancers, respectively, and then mixed with Fruc and Suc, respectively, to obtain six kinds of skin optical clearing agents (SOCAs). Optical coherence tomography angiography was applied to monitor SOCAs-induced changes in imaging performances, skin optical properties, refractive index mismatching extent, and permeability rate. Experimental results demonstrated that PEG+Thiaz+Suc has the optimal capacity in enhancing the imaging performances, decreasing the scattering and the refractive index mismatching since Thiaz is superior to PG, and Suc is superior to Fruc. This study indicates that the optimal SOCA can be obtained directly by means of additionally adding or replacing the similar category substance in preexisting SOCAs with some more effective reagents. It not only provides an optimal SOCA, but also provides a useful way to develop more effective SOCAs. Cross-section skin structural texture (a), reconstructed blood flow distribution information (b), before or after treated with different SOCAs.

  11. Sequential activation of ground pads reduces skin heating during radiofrequency tumor ablation: in vivo porcine results.

    PubMed

    Schutt, David J; Swindle, M Michael; Helke, Kristi L; Bastarrika, Gorka; Schwarz, Florian; Haemmerich, Dieter

    2010-03-01

    Skin burns below ground pads during monopolar RF ablation are increasingly prevalent, thereby hindering the development of higher power RF generators capable of creating larger tumor ablation zones in combination with multiple or new applicators. Our goal was to evaluate reduction in skin temperatures via additional ground pads in an in vivo porcine model. Three ground pads placed on the animal's abdomen were activated either simultaneously or sequentially, where activation timing was adjusted to equilibrate skin temperature below each pad. Thirteen RF ablations (n = 4 simultaneous at 300 W, n = 5 sequential at 300 W, and n = 4 sequential at 375 W) were performed for 12 min via two internally cooled cluster electrodes placed in the gluteus maximus of domestic swine. Temperature rise at each pad and burn degree as determined via histology were compared. Ablation zone size was determined via T2-weighted MRI. Maximum temperature rise was significantly higher with simultaneous activation than with either of the sequential activation group (21.4 degrees C versus 8.1 degrees C or 9.6 degrees C, p < 0.01). Ablation zone diameters during simultaneous (300 W) and sequential activations (300 and 375 W) were and 6.9 +/- 0.3, 5.6 +/- 0.3, and 7.5 +/- 0.6 cm, respectively. Sequential activation of multiple ground pads results in significantly lower skin temperatures and less severe burns, as measured by histological examination.

  12. Clinical study of noninvasive in vivo melanoma and nonmelanoma skin cancers using multimodal spectral diagnosis

    NASA Astrophysics Data System (ADS)

    Lim, Liang; Nichols, Brandon; Migden, Michael R.; Rajaram, Narasimhan; Reichenberg, Jason S.; Markey, Mia K.; Ross, Merrick I.; Tunnell, James W.

    2014-11-01

    The goal of this study was to determine the diagnostic capability of a multimodal spectral diagnosis (SD) for in vivo noninvasive disease diagnosis of melanoma and nonmelanoma skin cancers. We acquired reflectance, fluorescence, and Raman spectra from 137 lesions in 76 patients using custom-built optical fiber-based clinical systems. Biopsies of lesions were classified using standard histopathology as malignant melanoma (MM), nonmelanoma pigmented lesion (PL), basal cell carcinoma (BCC), actinic keratosis (AK), and squamous cell carcinoma (SCC). Spectral data were analyzed using principal component analysis. Using multiple diagnostically relevant principal components, we built leave-one-out logistic regression classifiers. Classification results were compared with histopathology of the lesion. Sensitivity/specificity for classifying MM versus PL (12 versus 17 lesions) was 100%;/100%;, for SCC and BCC versus AK (57 versus 14 lesions) was 95%;/71%, and for AK and SCC and BCC versus normal skin (71 versus 71 lesions) was 90%/85%. The best classification for nonmelanoma skin cancers required multiple modalities; however, the best melanoma classification occurred with Raman spectroscopy alone. The high diagnostic accuracy for classifying both melanoma and nonmelanoma skin cancer lesions demonstrates the potential for SD as a clinical diagnostic device.

  13. Polarization-Sensitive Hyperspectral Imaging in vivo: A Multimode Dermoscope for Skin Analysis

    NASA Astrophysics Data System (ADS)

    Vasefi, Fartash; MacKinnon, Nicholas; Saager, Rolf B.; Durkin, Anthony J.; Chave, Robert; Lindsley, Erik H.; Farkas, Daniel L.

    2014-05-01

    Attempts to understand the changes in the structure and physiology of human skin abnormalities by non-invasive optical imaging are aided by spectroscopic methods that quantify, at the molecular level, variations in tissue oxygenation and melanin distribution. However, current commercial and research systems to map hemoglobin and melanin do not correlate well with pathology for pigmented lesions or darker skin. We developed a multimode dermoscope that combines polarization and hyperspectral imaging with an efficient analytical model to map the distribution of specific skin bio-molecules. This corrects for the melanin-hemoglobin misestimation common to other systems, without resorting to complex and computationally intensive tissue optical models. For this system's proof of concept, human skin measurements on melanocytic nevus, vitiligo, and venous occlusion conditions were performed in volunteers. The resulting molecular distribution maps matched physiological and anatomical expectations, confirming a technologic approach that can be applied to next generation dermoscopes and having biological plausibility that is likely to appeal to dermatologists.

  14. Multi-spectral mapping of in vivo skin hemoglobin and melanin

    NASA Astrophysics Data System (ADS)

    Jakovels, Dainis; Spigulis, Janis; Saknite, Inga

    2010-04-01

    The multi-spectral imaging technique has been used for distant mapping of in-vivo skin chromophores by analyzing spectral data at each reflected image pixel and constructing 2-D maps of the relative concentrations of oxy-/deoxyhemoglobin and melanin. Instead of using a broad visible-NIR spectral range, this study focuses on narrowed spectral band 500-700 nm, so speeding-up the signal processing procedure. Regression analysis confirmed that superposition of three Gaussians is optimal analytic approximation for the oxy-hemoglobin absorption tabular spectrum in this spectral band, while superposition of two Gaussians fits well for deoxy-hemoglobin absorption and exponential function - for melanin absorption. The proposed approach was clinically tested for three types of in-vivo skin provocations - ultraviolet irradiance, chemical reaction with vinegar essence and finger arterial occlusion. Spectral range 500-700 nm provided better sensitivity to oxy-hemoglobin changes and higher response stability to melanin than two reduced ranges 500-600 nm and 530-620 nm.

  15. In Vitro and In Vivo Studies on Protective Action of N-Phenethyl Caffeamide against Photodamage of Skin

    PubMed Central

    Kuo, Yueh-Hsiung; Chen, Chien-Wen; Chu, Yin; Lin, Ping; Chiang, Hsiu-Mei

    2015-01-01

    In our previous study, N-phenethyl caffeamide (K36) was proved to act as an antioxidant and an antiphotoaging agent by inhibiting type I procollagen degradation and stimulating collagen synthesis in human skin fibroblasts. In the present study, in vitro and in vivo experiments were conducted to investigate the mechanism of action and the antiinflammatory and antiphotoaging activity of K36. K36 reduced UVB-induced cyclooxygenase-2 (COX-2) and inducible nitric oxide synthases (iNOS) expression by regulating IκB and p-IκB expression. K36 also inhibited the nuclear translocation of NF-κB. Furthermore, the inhibition of mitogen-activated protein (MAP) kinases by K36 was attributed to the downregulation of COX-2. Topically applying K36 led to efficient antiwrinkle formation and reduced UVB-induced erythema and thickness of epidermis in hairless mice. In addition, K36 penetrated into the skin of hairless mice. Our findings show that K36 has significant beneficial effects on antioxidant, antiinflammatory, and antiphotoaging activity and suggest that K36 can be developed as an antiaging agent for cosmetic and skin care products. PMID:26367260

  16. Characterization of a MOSkin detector for in vivo skin dose measurements during interventional radiology procedures

    SciTech Connect

    Safari, M. J.; Wong, J. H. D.; Ng, K. H.; Jong, W. L.; Cutajar, D. L.; Rosenfeld, A. B.

    2015-05-15

    Purpose: The MOSkin is a MOSFET detector designed especially for skin dose measurements. This detector has been characterized for various factors affecting its response for megavoltage photon beams and has been used for patient dose measurements during radiotherapy procedures. However, the characteristics of this detector in kilovoltage photon beams and low dose ranges have not been studied. The purpose of this study was to characterize the MOSkin detector to determine its suitability for in vivo entrance skin dose measurements during interventional radiology procedures. Methods: The calibration and reproducibility of the MOSkin detector and its dependency on different radiation beam qualities were carried out using RQR standard radiation qualities in free-in-air geometry. Studies of the other characterization parameters, such as the dose linearity and dependency on exposure angle, field size, frame rate, depth-dose, and source-to-surface distance (SSD), were carried out using a solid water phantom under a clinical x-ray unit. Results: The MOSkin detector showed good reproducibility (94%) and dose linearity (99%) for the dose range of 2 to 213 cGy. The sensitivity did not significantly change with the variation of SSD (±1%), field size (±1%), frame rate (±3%), or beam energy (±5%). The detector angular dependence was within ±5% over 360° and the dose recorded by the MOSkin detector in different depths of a solid water phantom was in good agreement with the Markus parallel plate ionization chamber to within ±3%. Conclusions: The MOSkin detector proved to be reliable when exposed to different field sizes, SSDs, depths in solid water, dose rates, frame rates, and radiation incident angles within a clinical x-ray beam. The MOSkin detector with water equivalent depth equal to 0.07 mm is a suitable detector for in vivo skin dosimetry during interventional radiology procedures.

  17. The Microbiota of the Human Skin.

    PubMed

    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,

  18. Measuring skin aging using optical coherence tomography in vivo: a validation study

    NASA Astrophysics Data System (ADS)

    Trojahn, Carina; Dobos, Gabor; Richter, Claudia; Blume-Peytavi, Ulrike; Kottner, Jan

    2015-04-01

    Dermal and epidermal structures in human skin change during intrinsic and extrinsic aging. Epidermal thickness is one of the most often reported parameters for the assessment of skin aging in cross-sectional images captured by optical coherence tomography (OCT). We aimed to identify further parameters for the noninvasive measurement of skin aging of sun-exposed and sun-protected areas utilizing OCT. Based on a literature review, seven parameters were inductively developed. Three independent raters assessed these parameters using four-point scales on images of female subjects of two age groups. All items could be detected and quantified in our sample. Interrater agreement ranged between 25.0% and 83.3%. The item scores "stratum corneum reflectivity," "upper dermal reflectivity," and "dermoepidermal contrast" showed significant differences between age groups on the volar and dorsal forearm indicating that they were best able to measure changes during skin aging. "Surface unevenness" was associated with the skin roughness parameters, Rz and Rmax, on the inner upper arm and volar forearm supporting the criterion validity of this parameter on sun-protected skin areas. Based on the interrater agreement and the ability to differentiate between age groups, these four parameters are being considered as the best candidates for measuring skin aging in OCT images.

  19. CCN1 contributes to skin connective tissue aging by inducing age-associated secretory phenotype in human skin dermal fibroblasts.

    PubMed

    Quan, Taihao; Qin, Zhaoping; Robichaud, Patrick; Voorhees, John J; Fisher, Gary J

    2011-08-01

    Dermal connective tissue collagen is the major structural protein in skin. Fibroblasts within the dermis are largely responsible for collagen production and turnover. We have previously reported that dermal fibroblasts, in aged human skin in vivo, express elevated levels of CCN1, and that CCN1 negatively regulates collagen homeostasis by suppressing collagen synthesis and increasing collagen degradation (Quan et al. Am J Pathol 169:482-90, 2006, J Invest Dermatol 130:1697-706, 2010). In further investigations of CCN1 actions, we find that CCN1 alters collagen homeostasis by promoting expression of specific secreted proteins, which include matrix metalloproteinases and proinflammatory cytokines. We also find that CCN1-induced secretory proteins are elevated in aged human skin in vivo. We propose that CCN1 induces an "Age-Associated Secretory Phenotype", in dermal fibroblasts, which mediates collagen reduction and fragmentation in aged human skin.

  20. In vivo imaging of the human rod photoreceptor mosaic

    PubMed Central

    Doble, Nathan; Choi, Stacey S.; Codona, Johanan L.; Christou, Julian; Enoch, Jay M.; Williams, David R.

    2011-01-01

    Although single cone receptors have been imaged in the living human eye, there has been no observation of rods in vivo. Using an adaptive optics (AO) ophthalmoscope and post processing, evidence of rod mosaic was observed at 5° and 10° eccentricities in the horizontal, temporal retina. For 4 normal human subjects, small structures were observed in between the larger cones, and were observed repeatedly at the same locations on different days and with varying wavelengths. Image analysis gave spacings that agree well with rod measurements from histological data. PMID:21209677

  1. Human platelet gel supernatant inactivates opportunistic wound pathogens on skin.

    PubMed

    Edelblute, Chelsea M; Donate, Amy L; Hargrave, Barbara Y; Heller, Loree C

    2015-01-01

    Activation of human platelets produces a gel-like substance referred to as platelet rich plasma or platelet gel. Platelet gel is used clinically to promote wound healing; it also exhibits antimicrobial properties that may aid in the healing of infected wounds. The purpose of this study was to quantify the efficacy of human platelet gel against the opportunistic bacterial wound pathogens Acinetobacter baumannii, Pseudomonas aeruginosa, and Staphylococcus aureus on skin. These opportunistic pathogens may exhibit extensive antibiotic resistance, necessitating the development of alternative treatment options. The antimicrobial efficacy of platelet gel supernatants was quantified using an in vitro broth dilution assay, an ex vivo inoculated skin assay, and in an in vivo skin decontamination assay. Human platelet gel supernatants were highly bactericidal against A. baumannii and moderately but significantly bactericidal against S. aureus in vitro and in the ex vivo skin model. P. aeruginosa was not inactivated in vitro; a low but significant inactivation level was observed ex vivo. These supernatants were quite effective at inactivating a model organism on skin in vivo. These results suggest application of platelet gel has potential clinical applicability, not only in the acceleration of wound healing, but also against relevant bacteria causing wound infections.

  2. Data sources for in vivo molecular profiling of human phenotypes.

    PubMed

    Cardozo, Timothy; Gupta, Priyanka; Ni, Eric; Young, Lauren M; Tivon, Doreen; Felsovalyi, Klara

    2016-11-01

    Molecular profiling of human diseases has been approached at the genetic (DNA), expression (RNA), and proteomic (protein) levels. An important goal of these efforts is to map observed molecular patterns to specific, mechanistic organic entities, such as loci in the genome, individual RNA molecules or defined proteins or protein assemblies. Importantly, such maps have been historically approached in the more intuitive context of a theoretical individual cell, but diseases are better described in reality using an in vivo framework, namely a library of several tissue-specific maps. In this article, we review the existing data atlases that can be used for this purpose and identify critical gaps that could move the field forward from cellular to in vivo dimensions. WIREs Syst Biol Med 2016, 8:472-484. doi: 10.1002/wsbm.1354 For further resources related to this article, please visit the WIREs website.

  3. Review of the results of the in vivo dosimetry during total skin electron beam therapy

    PubMed Central

    Guidi, Gabriele; Gottardi, Giovanni; Ceroni, Paola; Costi, Tiziana

    2013-01-01

    This work reviews results of in vivo dosimetry (IVD) for total skin electron beam (TSEB) therapy, focusing on new methods, data emerged within 2012. All quoted data are based on a careful review of the literature reporting IVD results for patients treated by means of TSEB therapy. Many of the reviewed papers refer mainly to now old studies and/or old guidelines and recommendations (by IAEA, AAPM and EORTC), because (due to intrinsic rareness of TSEB-treated pathologies) only a limited number of works and reports with a large set of numerical data and proper statistical analysis is up-to-day available in scientific literature. Nonetheless, a general summary of the results obtained by the now numerous IVD techniques available is reported; innovative devices and methods, together with areas of possible further and possibly multicenter investigations for TSEB therapies are highlighted. PMID:24936333

  4. In vivo behavior of murine epidermal cell lines derived from initiated and noninitiated skin.

    PubMed

    Conti, C J; Fries, J W; Viaje, A; Miller, D R; Morris, R; Slaga, T J

    1988-01-15

    The in vivo behavior of cell cultures derived from normal and carcinogen-treated mouse epidermis was studied by implanting the cultures in a s.c. vascularized bed protected by a silicone chamber. Cells derived from normal adult mouse epidermis as well as cells derived from tumor-promoter-treated skin were unable to grow in these systems. Conversely, cell lines derived from skin initiated with single doses of N-methyl-N'-nitro-N-nitrosoguanidine or 9,10-dimethyl-1,2-benzanthracene proliferated in these chambers, reforming an epithelial structure. The type of structure in the chambers varied, ranging from formation of almost normal epithelia to atypical invasive behavior. The variable in vivo behavior among the different cell lines may be attributed to the initiation agent, the number of passages of the cultures, random genetic events, the strain of mouse, or a combination of these factors. Most of the cell types used in this study and all the cell lines that were able to grow in these chambers were selected for resistance to Ca-induced terminal differentiation. However, resistance to terminal differentiation according to the Ca2+ switch does not always correlate with the ability to grow in the chambers, since cell lines derived from spontaneous foci of resistance failed to grow in this system. These studies showed some of the possibilities of the SC silicone chambers to study the histogenic potential of cell lines derived from carcinogen-treated epidermis. This system also appears suitable to study the complex relationship between epidermal cells and specialized (dermal) stroma.

  5. Characterization and antioxidant activity in vitro and in vivo of polysaccharide purified from Rana chensinensis skin.

    PubMed

    Wang, Zhanyong; Zhao, Yuanyuan; Su, Tingting; Zhang, Jing; Wang, Fei

    2015-08-01

    Preliminary characterization and antioxidant activity in vitro and in vivo investigation of the polysaccharide fraction named as RCSP II, which was extracted from Rana chensinensis skin, were performed. Results indicated that RCSP II comprised glucose, galactose, and mannose in a molar ratio of 87.82:2.77:1.54 with a molecular weight of 12.8 kDa. Antioxidant activity assay in vitro showed that RCSP II exhibited 75.2% scavenging activity against 2,2'-azino-bis(3-ethylbenz-thiazoline-6-sulfonic acid) radicals at the concentration of 2500 mg/L and 85.1% against chelated ferrous ion at 4000 mg/L. Antioxidant activity assay in vivo further showed that RCSP II increased the activities of antioxidant enzymes, decreased the levels of malondialodehyde, and enhanced total antioxidant capabilities in livers and sera of d-galactose induced mice. These results suggested that RCSP II could have potential antioxidant applications as medicine or functional food.

  6. Influence of IR radiation on the carotenoid content in human skin

    NASA Astrophysics Data System (ADS)

    Darvin, M. E.; Zastrov, L.; Gonchukov, S. A.; Lademann, J.

    2009-12-01

    It is shown that the infrared irradiation decreases the content of β-carotene and lycopene carotenoids in human skin. A decrease in the content of β-carotene and lycopene may indicate that the IR radiation, as well as the UV radiation, is capable of forming free radicals in human skin. The investigations were performed in vivo using the technique of resonance Raman scattering developed by us for the noninvasive determination of antioxidant potential in skin.

  7. Development of an innervated model of human skin.

    PubMed

    Khammo, Nancy; Ogilvie, Jane; Clothier, Richard H

    2007-10-01

    Neuronal cell responses and interactions with the epithelial and fibroblastic cells of the skin are a key factor in the production in vivo of the irritation/inflammatory response. Currently, few in vitro models are available that contain dermal, epidermal and the relevant neuronal components. The primary objective of this study was to produce and maintain a 3-D in vitro model of human skin containing these elements. The relevant neuronal component was supplied by adding sensory neurons derived from the dorsal root ganglion (DRG). Since adult neuronal cells do not grow significantly in vivo or in vitro, and since it is very difficult to obtain such cells from humans, it was necessary to employ embryonic rat DRG cells. The ultimate purpose of this model is to improve prediction of the in vivo skin irritancy potential of chemicals and formulations, without the need to use animal models. In addition, this approach has also been applied to the in vitro human eye and bronchial 3-D models being developed in the FRAME Alternatives Laboratory.

  8. Antiphotoaging Effect of Conditioned Medium of Dedifferentiated Adipocytes on Skin In Vivo and In Vitro: A Mechanistic Study

    PubMed Central

    Xu, Yang; Zhang, Jia-an; Xu, Yan; Guo, Shi-lei; Wang, Shen; Wu, Di; Wang, Ying

    2015-01-01

    Photoaging of skin occurs partially due to decreased synthesis and increased degradation of dermal collagen. Antiphotoaging therapy aims to counteract these effects. This study aimed to investigate whether secretory factors from dedifferentiated adipocytes (DAs) could alleviate photoaging in human dermal fibroblasts (HDFs) and in mice and to clarify the underlying mechanism. DAs were acquired and verified based on cellular biomarkers and multilineage differentiation potential. The concentrations of several cytokines in conditioned medium from DAs (DA-CM) were determined. In vivo pathological changes, collagen types I and III, and matrix metalloproteinase (MMP)-1 and -3 were evaluated following the injection of 10-fold concentrated DA-CM into photoaged mice. In vitro, the effect of DA-CM on stress-induced premature senescence in HDFs was investigated by 5-ethynyl-2′-deoxyuridine (EdU) staining and β-galactosidase staining. The influence of DA-CM and transforming growth factor-β1 (TGF-β1) on the secretion of collagen types I and III, MMP-1, and MMP-3 in HDFs was evaluated by ELISA. In vivo, we found that subcutaneously injected 10-fold concentrated DA-CM increased the expression of collagen types I and III. In vitro, DA-CM clearly mitigated the decreased cell proliferation and delayed the senescence status in HDFs induced by ultraviolet B (UVB). HDFs treated with DA-CM exhibited higher collagen types I and III secretion and significantly lower MMP-1 and MMP-3 secretion. The TGF-β1-neutralizing antibody could partially reduce the recovery effect. Our results suggest that DAs may be useful for aging skin and their effects are mainly due to secreted factors, especially TGF-β1, which stimulate collagen synthesis and alleviate collagen degradation in HDFs. PMID:25517994

  9. Triparanol suppresses human tumor growth in vitro and in vivo

    SciTech Connect

    Bi, Xinyu; Han, Xingpeng; Zhang, Fang; He, Miao; Zhang, Yi; Zhi, Xiu-Yi; Zhao, Hong

    2012-08-31

    Highlights: Black-Right-Pointing-Pointer Demonstrate Triparanol can block proliferation in multiple cancer cells. Black-Right-Pointing-Pointer Demonstrate Triparanol can induce apoptosis in multiple cancer cells. Black-Right-Pointing-Pointer Proved Triparanol can inhibit Hedgehog signaling in multiple cancer cells. Black-Right-Pointing-Pointer Demonstrated Triparanol can impede tumor growth in vivo in mouse xenograft model. -- Abstract: Despite the improved contemporary multidisciplinary regimens treating cancer, majority of cancer patients still suffer from adverse effects and relapse, therefore posing a significant challenge to uncover more efficacious molecular therapeutics targeting signaling pathways central to tumorigenesis. Here, our study have demonstrated that Triparanol, a cholesterol synthesis inhibitor, can block proliferation and induce apoptosis in multiple human cancer cells including lung, breast, liver, pancreatic, prostate cancer and melanoma cells, and growth inhibition can be rescued by exogenous addition of cholesterol. Remarkably, we have proved Triparanol can significantly repress Hedgehog pathway signaling in these human cancer cells. Furthermore, study in a mouse xenograft model of human lung cancer has validated that Triparanol can impede tumor growth in vivo. We have therefore uncovered Triparanol as potential new cancer therapeutic in treating multiple types of human cancers with deregulated Hedgehog signaling.

  10. Transient Genome-Wide Transcriptional Response to Low-Dose Ionizing Radiation In Vivo in Humans

    SciTech Connect

    Berglund, Susanne R.; Rocke, David M.; Dai Jian; Schwietert, Chad W.; Santana, Alison; Stern, Robin L.; Lehmann, Joerg; Hartmann Siantar, Christine L.; Goldberg, Zelanna

    2008-01-01

    Purpose: The in vivo effects of low-dose low linear energy transfer ionizing radiation on healthy human skin are largely unknown. Using a patient-based tissue acquisition protocol, we have performed a series of genomic analyses on the temporal dynamics over a 24-hour period to determine the radiation response after a single exposure of 10 cGy. Methods and Materials: RNA from each patient tissue sample was hybridized to an Affymetrix Human Genome U133 Plus 2.0 array. Data analysis was performed on selected gene groups and pathways. Results: Nineteen gene groups and seven gene pathways that had been shown to be radiation responsive were analyzed. Of these, nine gene groups showed significant transient transcriptional changes in the human tissue samples, which returned to baseline by 24 hours postexposure. Conclusions: Low doses of ionizing radiation on full-thickness human skin produce a definable temporal response out to 24 hours postexposure. Genes involved in DNA and tissue remodeling, cell cycle transition, and inflammation show statistically significant changes in expression, despite variability between patients. These data serve as a reference for the temporal dynamics of ionizing radiation response following low-dose exposure in healthy full-thickness human skin.

  11. Detectability of contrast agents for video-rate confocal reflectance microscopy of skin and microcirculation in vivo

    NASA Astrophysics Data System (ADS)

    Rajadhyaksha, Milind M.; Gonzalez, Salvador

    2003-06-01

    The lack of structure-specific contrast limits the usefulness of confocal reflectance microscopy to morphologic investigations at the cellular- and nuclear-level in human and animal skin in vivo. Morphologic and functional imaging at specific organelle- and ultrastructure-levels will require contrast agents that may be used and detected in vivo. High-resolution confocal reflectance imaging is based on the detection of singly back-scattered photons, where contrast is provided by variations in the refractive indices of microstructures. We carried out a quantitative Mie back-scatter analysis and imaging experiments to understand signal detectability of reflectance contrast agents for visualizing human skin and animal microcirculation. When imaging at video-rate with illumination of 10 milliwatts at 1064 nm, we detect 100-104 photons/pixel from the epidermis to dermis, relative to a background of 100 photons; this provides a signal-to-noise ratio of 3-40 and signal-to-background of 1-100. Organelles of size (d) 0.1-1.0 μm with refractive indices (n) of 1.34-1.45 (relative to n=1.34 for epidermis, n=1.38 for dermis) back-scatter 10-104 photons/pixel. Exogenous contrast agents such as liposomes (n=1.41, d=0.7 μm) and polystyrene microspheres (d=0.2-1.0 μm, n=1.57; 100-105 photons/pixel) are detectable and they strongly enhance the contrast of microcirculation in the dermis of Sprague-Dawley rats. Topically applied 5% acetic acid causes the intra-nuclear 30-100 nm-thin chromatin filaments to condense into 1-5 μm-thick strands, increasing back-scattered signal from 100 to 104 photons/pixels, making the nuclei appear bright and easily detectable in basal cell cancers. Such analyses provide a basis for optimizing confocal microscope design for detectability of contrast agents in vivo.

  12. Tattooing of skin results in transportation and light-induced decomposition of tattoo pigments--a first quantification in vivo using a mouse model.

    PubMed

    Engel, Eva; Vasold, Rudolf; Santarelli, Francesco; Maisch, Tim; Gopee, Neera V; Howard, Paul C; Landthaler, Michael; Bäumler, Wolfgang

    2010-01-01

    Millions of people are tattooed with inks that contain azo pigments. The pigments contained in tattoo inks are manufactured for other uses with no established history of safe use in humans and are injected into the skin at high densities (2.5 mg/cm(2)). Tattoo pigments disseminate after tattooing throughout the human body and although some may photodecompose at the injection site by solar or laser light exposure, the extent of transport or photodecomposition under in vivo conditions remains currently unknown. We investigated the transport and photodecomposition of the widely used tattoo Pigment Red 22 (PR 22) following tattooing into SKH-1 mice. The pigment was extracted quantitatively at different times after tattooing. One day after tattooing, the pigment concentration was 186 microg/cm(2) skin. After 42 days, the amount of PR 22 in the skin has decreased by about 32% of the initial value. Exposure of the tattooed skin, 42 days after tattooing, to laser light reduced the amount of PR 22 by about 51% as compared to skin not exposed to laser light. A part of this reduction is as a result of photodecomposition of PR 22 as shown by the detection of corresponding hazardous aromatic amines. Irradiation with solar radiation simulator for 32 days caused a pigment reduction of about 60% and we again assume pigment decomposition in the skin. This study is the first quantitative estimate of the amount of tattoo pigments transported from the skin into the body or decomposed by solar or laser radiation.

  13. Human papillomaviruses and skin cancer.

    PubMed

    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.

  14. Penetration of nanoparticles into human skin.

    PubMed

    Liang, Xiao Wen; Xu, Zhi Ping; Grice, Jeffrey; Zvyagin, Andrei V; Roberts, Michael S; Liu, Xin

    2013-01-01

    Exposure of human skin to nanoparticles (NPs) is increasing with the development of nanotechnology and new applications of NPs in medicine. Safety concerns have sparked debate on the capacity of NPs to penetrate through skin and enter into the body. This article attempts to summarize the recent evidence on whether NPs penetrate human skin and the factors that may affect the penetration. Skin structure and penetration mechanisms are reviewed to provide background information. Size, shape, formulation, surface properties and application methods and their effects on skin penetration are specifically discussed. Finally, the relationship between skin penetration and nanotoxicity is reviewed to further emphasise the importance of the research in this area.

  15. [Experimental models of human skin aging].

    PubMed

    Nikolakis, G; Zoschke, C; Makrantonaki, E; Hausmann, C; Schäfer-Korting, M; Zouboulis, C C

    2016-02-01

    The skin is a representative model for the study of human aging. Despite the high regenerative capacity of the skin, skin physiology changes over the course of life. Medical and cosmetic research is trying to prevent aging, to slow, to stop, or to reverse it. Effects of age-related DNA damage and of changing skin structure on pharmacological parameters are largely unknown. This review article summarizes the state of scientific knowledge in the field of experimental models of human skin aging and shows approaches to improve organotypic skin models, to develop predictive models of aging, and improve aging research.

  16. Real-time Raman spectroscopy for automatic in vivo skin cancer detection: an independent validation.

    PubMed

    Zhao, Jianhua; Lui, Harvey; Kalia, Sunil; Zeng, Haishan

    2015-11-01

    In a recent study, we have demonstrated that real-time Raman spectroscopy could be used for skin cancer diagnosis. As a translational study, the objective of this study is to validate previous findings through a completely independent clinical test. In total, 645 confirmed cases were included in the analysis, including a cohort of 518 cases from a previous study, and an independent cohort of 127 new cases. Multi-variant statistical data analyses including principal component with general discriminant analysis (PC-GDA) and partial least squares (PLS) were used separately for lesion classification, which generated similar results. When the previous cohort (n = 518) was used as training and the new cohort (n = 127) was used as testing, the area under the receiver operating characteristic curve (ROC AUC) was found to be 0.889 (95 % CI 0.834-0.944; PLS); when the two cohorts were combined, the ROC AUC was 0.894 (95 % CI 0.870-0.918; PLS) with the narrowest confidence intervals. Both analyses were comparable to the previous findings, where the ROC AUC was 0.896 (95 % CI 0.846-0.946; PLS). The independent study validates that real-time Raman spectroscopy could be used for automatic in vivo skin cancer diagnosis with good accuracy.

  17. In vivo imaging reveals a pioneer wave of monocyte recruitment into mouse skin wounds.

    PubMed

    Rodero, Mathieu P; Licata, Fabrice; Poupel, Lucie; Hamon, Pauline; Khosrotehrani, Kiarash; Combadiere, Christophe; Boissonnas, Alexandre

    2014-01-01

    The cells of the mononuclear phagocyte system are essential for the correct healing of adult skin wounds, but their specific functions remain ill-defined. The absence of granulation tissue immediately after skin injury makes it challenging to study the role of mononuclear phagocytes at the initiation of this inflammatory stage. To study their recruitment and migratory behavior within the wound bed, we developed a new model for real-time in vivo imaging of the wound, using transgenic mice that express green and cyan fluorescent proteins and specifically target monocytes. Within hours after the scalp injury, monocytes invaded the wound bed. The complete abrogation of this infiltration in monocyte-deficient CCR2(-/-) mice argues for the involvement of classical monocytes in this process. Monocyte infiltration unexpectedly occurred as early as neutrophil recruitment did and resulted from active release from the bloodstream toward the matrix through microhemorrhages rather than transendothelial migration. Monocytes randomly scouted around the wound bed, progressively slowed down, and stopped. Our approach identified and characterized a rapid and earlier than expected wave of monocyte infiltration and provides a novel framework for investigating the role of these cells during early stages of wound healing.

  18. In vivo photoacoustic microscopy of human cutaneous microvasculature and a nevus

    NASA Astrophysics Data System (ADS)

    Favazza, Christopher P.; Jassim, Omar; Cornelius, Lynn A.; Wang, Lihong V.

    2011-01-01

    In several human volunteers, photoacoustic microscopy (PAM) has been utilized for noninvasive cutaneous imaging of the skin microvasculature and a melanocytic nevus. Microvascular networks in both acral and nonacral skin were imaged, and multiple features within the skin have been identified, including the stratum corneum, epidermal-dermal junction, and subpapillary vascular plexus. Several vascular and structural differences between acral and nonacral skin were also observed in the photoacoustic images. In addition, a nevus was photoacoustically imaged, excised, and histologically analyzed. The photoacoustic images allowed for in vivo measurement of tumor thickness, depth, and microvasculature-values confirmed by histologic examination. The presented images demonstrate the potential of PAM to aid in the study and evaluation of cutaneous microcirculation and analysis of pigmented lesions. Through its ability to three-dimensionally image the structure and function of the microvasculature and pigmented lesions, PAM can have a clinical impact in diagnosis and assessment of systemic diseases that affect the microvasculature such as diabetes and cardiovascular disease, cutaneous malignancies such as melanoma, and potentially other skin disorders.

  19. In vivo imaging of human burn injuries with polarization-sensitive optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Kim, Ki Hean; Pierce, Mark C.; Maguluri, Gopi; Park, B. Hyle; Yoon, Sang June; Lydon, Martha; Sheridan, Robert; de Boer, Johannes F.

    2012-06-01

    The accurate determination of burn depth is critical in the clinical management of burn wounds. Polarization-sensitive optical coherence tomography (PS-OCT) has been proposed as a potentially non-invasive method for determining burn depth by measuring thermally induced changes in the structure and birefringence of skin, and has been investigated in pre-clinical burn studies with animal models and ex vivo human skin. In this study, we applied PS-OCT to the in-vivo imaging of two pediatric burn patients. Deep and superficial burned skins along with contralateral controls were imaged in 3D. The imaging size was 8 mm×6 mm×2 mm in width, length, and depth in the air respectively, and the imaging time was approximately 6 s per volume. Superficially burned skins exhibited the same layered structure as the contralateral controls, but more visible vasculature and reduced birefringence compared to the contralateral controls. In contrast, a deeply burned skin showed loss of the layered structure, almost absent vasculature, and smaller birefringence compared to superficial burns. This study suggested the vasculature and birefringence as parameters for characterizing burn wounds.

  20. Interpreting diffuse reflectance for in vivo skin reactions in terms of chromophores.

    PubMed

    Kollias, Nikiforos; Seo, InSeok; Bargo, Paulo R

    2010-01-01

    The measurement and quantification of skin reactions to insults involves certain assumptions about the relation between intensity of color appearance of the skin and the concentration of endogenous chromophores. The underlying assumption is that the Beer-Lambert law is obeyed, i.e., that a linear relation exists between the absorbance and the concentration of each chromophore and that the total absorbance is the linear superposition of the contributions of each chromophore. In this paper the authors compiled the results from a number of interventions on human skin that result in changes in its appearance and small deviations from the homeostatic state, where the results may be accounted for by a single or multiple chromophores. The validity of the assumptions is found to hold for a limited range of responses. The biological constraints need to be considered in certain cases because as we move away from the homeostatic state, complex biological processes are induced.

  1. Three-dimensional confocal fluorescence microscopic visualization of the living human skin

    NASA Astrophysics Data System (ADS)

    Masters, Barry R.

    1995-04-01

    Three-dimensional confocal visualization of living human skin is a new development in the noninvasive imaging of normal and pathological tissue. I have investigated the autofluorescence of in vivo human skin with a laser scanning confocal microscope. An argon ion laser (488 nm) was used for excitation of the natural fluorescence of skin and a 515 nm cut off filter was used to separate the fluorescence from the excitation light. I found that normal skin has a very high autofluorescence. The laser scanning confocal microscope was used to obtain a stack of serial sections through the skin. A stack of optical sections through the hair follicle was reconstructed as well as the three-dimensional reconstruction of the pores of sweat glands. The ability to obtain two and three-dimensional visualizations of in vivo human skin may provide a new tool for noninvasive diagnostics in dermatology.

  2. Determination of in vivo protein synthesis in human palatine tonsil.

    PubMed

    Januszkiewicz, Anna; Klaude, Maria; Loré, Karin; Andersson, Jan; Ringdén, Olle; Rooyackers, Olav; Wernerman, Jan

    2005-02-01

    The palatine tonsils are constantly exposed to ingested or inhaled antigens which, in turn, lead to a permanent activation of tonsillar immune cells, even in a basic physiological state. The aim of the present study was to investigate if the immunological activation of the human palatine tonsil is reflected by a high metabolic activity, as determined by in vivo measurement of protein synthesis. The protein synthesis rate of the tonsil was also compared with that of the circulating T-lymphocytes, the total blood mononuclear cells and the whole population of blood leucocytes. Phenotypic characterization of immune-competent cells in tonsil tissue and blood was performed by flow cytometry. Pinch tonsil biopsies were taken after induction of anaesthesia in healthy adult patients (n=12) scheduled for ear surgery, uvulopalatopharyngoplasty or nose surgery. Protein synthesis was quantitatively determined during a 90-min period by a flooding-dose technique. The in vivo protein synthesis rate in the palatine tonsils was 22.8+/-5.7%/24 h (mean+/-S.D.), whereas protein synthesis in the circulating T-lymphocytes was 10.7+/-3.4%/24 h, in mononuclear cells was 10.8+/-2.8%/24 h and in leucocytes was 3.2+/-1.2%/24 h. CD3+ lymphocytes were the most abundant cell population in the tonsil. The in vivo protein synthesis rate in human tonsils was higher compared with the circulating immune cells. This high metabolic rate may reflect the permanent immunological activity present in human tonsils, although cell phenotypes and activity markers do not explain the differences.

  3. In vivo assessment of human burn scars through automated quantification of vascularity using optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Liew, Yih Miin; McLaughlin, Robert A.; Gong, Peijun; Wood, Fiona M.; Sampson, David D.

    2013-06-01

    In scars arising from burns, objective assessment of vascularity is important in the early identification of pathological scarring, and in the assessment of progression and treatment response. We demonstrate the first clinical assessment and automated quantification of vascularity in cutaneous burn scars of human patients in vivo that uses optical coherence tomography (OCT). Scar microvasculature was delineated in three-dimensional OCT images using speckle decorrelation. The diameter and area density of blood vessels were automatically quantified. A substantial increase was observed in the measured density of vasculature in hypertrophic scar tissues (38%) when compared against normal, unscarred skin (22%). A proliferation of larger vessels (diameter≥100 μm) was revealed in hypertrophic scarring, which was absent from normal scars and normal skin over the investigated physical depth range of 600 μm. This study establishes the feasibility of this methodology as a means of clinical monitoring of scar progression.

  4. Multidirectional In Vivo Characterization of Skin Using Wiener Nonlinear Stochastic System Identification Techniques.

    PubMed

    Parker, Matthew D; Jones, Lynette A; Hunter, Ian W; Taberner, A J; Nash, M P; Nielsen, P M F

    2017-01-01

    A triaxial force-sensitive microrobot was developed to dynamically perturb skin in multiple deformation modes, in vivo. Wiener static nonlinear identification was used to extract the linear dynamics and static nonlinearity of the force-displacement behavior of skin. Stochastic input forces were applied to the volar forearm and thenar eminence of the hand, producing probe tip perturbations in indentation and tangential extension. Wiener static nonlinear approaches reproduced the resulting displacements with variances accounted for (VAF) ranging 94-97%, indicating a good fit to the data. These approaches provided VAF improvements of 0.1-3.4% over linear models. Thenar eminence stiffness measures were approximately twice those measured on the forearm. Damping was shown to be significantly higher on the palm, whereas the perturbed mass typically was lower. Coefficients of variation (CVs) for nonlinear parameters were assessed within and across individuals. Individual CVs ranged from 2% to 11% for indentation and from 2% to 19% for extension. Stochastic perturbations with incrementally increasing mean amplitudes were applied to the same test areas. Differences between full-scale and incremental reduced-scale perturbations were investigated. Different incremental preloading schemes were investigated. However, no significant difference in parameters was found between different incremental preloading schemes. Incremental schemes provided depth-dependent estimates of stiffness and damping, ranging from 300 N/m and 2 Ns/m, respectively, at the surface to 5 kN/m and 50 Ns/m at greater depths. The device and techniques used in this research have potential applications in areas, such as evaluating skincare products, assessing skin hydration, or analyzing wound healing.

  5. Polarization-Sensitive Hyperspectral Imaging in vivo: A Multimode Dermoscope for Skin Analysis

    PubMed Central

    Vasefi, Fartash; MacKinnon, Nicholas; Saager, Rolf B.; Durkin, Anthony J.; Chave, Robert; Lindsley, Erik H.; Farkas, Daniel L.

    2014-01-01

    Attempts to understand the changes in the structure and physiology of human skin abnormalities by non-invasive optical imaging are aided by spectroscopic methods that quantify, at the molecular level, variations in tissue oxygenation and melanin distribution. However, current commercial and research systems to map hemoglobin and melanin do not correlate well with pathology for pigmented lesions or darker skin. We developed a multimode dermoscope that combines polarization and hyperspectral imaging with an efficient analytical model to map the distribution of specific skin bio-molecules. This corrects for the melanin-hemoglobin misestimation common to other systems, without resorting to complex and computationally intensive tissue optical models. For this system's proof of concept, human skin measurements on melanocytic nevus, vitiligo, and venous occlusion conditions were performed in volunteers. The resulting molecular distribution maps matched physiological and anatomical expectations, confirming a technologic approach that can be applied to next generation dermoscopes and having biological plausibility that is likely to appeal to dermatologists. PMID:24815987

  6. Human percutaneous absorption of a direct hair dye comparing in vitro and in vivo results: implications for safety assessment and animal testing.

    PubMed

    Lademann, J; Richter, H; Jacobi, U; Patzelt, A; Hueber-Becker, F; Ribaud, C; Benech-Kieffer, F; Dufour, E K; Sterry, W; Schaefer, H; Leclaire, J; Toutain, H; Nohynek, G J

    2008-06-01

    Although in vitro skin absorption studies often detect small residues of applied test material in the epidermis/dermis, it is uncertain whether the residue is within the living skin. We studied the dermal absorption of a hair dye hydroxyanthraquinone-aminopropyl methyl morpholinium methosulphate (HAM) in human skin in vivo and in vitro. In vivo, skin (back and scalp) received 0.5% HAM in a commercial formulation at 20microg/cm2 After 0.5 or 48h, skin was tape stripped, followed by cyanoacrylate biopsies (CAB). Sebum from scalp sites was collected for 48h. In vitro, skin was treated with 20mg/cm2 dye for 0.5h, penetration determined after 24h. In vivo, at 0.5h, total recovery (back) was 0.67microg/cm2 (tape strips+CAB). Fluorescence microscopy showed HAM in the hair follicle openings (HFO). At 0.5h, scalp tape strips contained 1.80microg/cm2, HFO 0.82microg/cm2. At 48h, HFO contained 0.21microg/cm2, sebum 0.80microg/cm2. In vivo, skin residues were in the non-living skin and eliminated via desquamation and sebum secretion. In vitro, the SC contained 1.50microg/cm2, epidermis/dermis 0.86microg/cm2, receptor fluid<0.04microg/cm2, a total of 0.90microg/cm2 was considered to be bioavailable. In vitro epidermis/dermis residues were nearly identical to those located in non-living skin in vivo. In conclusion, in vitro percutaneous penetration studies may produce seemingly bioavailable material , which raises the need for a Threshold of Skin Absorption (TSA) addressing a negligible dermal absorption in order to avoid unnecessary in vivo toxicity studies on substances that produce no significant human systemic exposure.

  7. Efficient in vivo gene editing using ribonucleoproteins in skin stem cells of recessive dystrophic epidermolysis bullosa mouse model.

    PubMed

    Wu, Wenbo; Lu, Zhiwei; Li, Fei; Wang, Wenjie; Qian, Nannan; Duan, Jinzhi; Zhang, Yu; Wang, Fengchao; Chen, Ting

    2017-02-14

    The prokaryotic CRISPR/Cas9 system has recently emerged as a powerful tool for genome editing in mammalian cells with the potential to bring curative therapies to patients with genetic diseases. However, efficient in vivo delivery of this genome editing machinery and indeed the very feasibility of using these techniques in vivo remain challenging for most tissue types. Here, we show that nonreplicable Cas9/sgRNA ribonucleoproteins can be used to correct genetic defects in skin stem cells of postnatal recessive dystrophic epidermolysis bullosa (RDEB) mice. We developed a method to locally deliver Cas9/sgRNA ribonucleoproteins into the skin of postnatal mice. This method results in rapid gene editing in epidermal stem cells. Using this method, we show that Cas9/sgRNA ribonucleoproteins efficiently excise exon80, which covers the point mutation in our RDEB mouse model, and thus restores the correct localization of the collagen VII protein in vivo. The skin blistering phenotype is also significantly ameliorated after treatment. This study provides an in vivo gene correction strategy using ribonucleoproteins as curative treatment for genetic diseases in skin and potentially in other somatic tissues.

  8. Efficient in vivo gene editing using ribonucleoproteins in skin stem cells of recessive dystrophic epidermolysis bullosa mouse model

    PubMed Central

    Wu, Wenbo; Lu, Zhiwei; Li, Fei; Wang, Wenjie; Qian, Nannan; Duan, Jinzhi; Zhang, Yu; Wang, Fengchao; Chen, Ting

    2017-01-01

    The prokaryotic CRISPR/Cas9 system has recently emerged as a powerful tool for genome editing in mammalian cells with the potential to bring curative therapies to patients with genetic diseases. However, efficient in vivo delivery of this genome editing machinery and indeed the very feasibility of using these techniques in vivo remain challenging for most tissue types. Here, we show that nonreplicable Cas9/sgRNA ribonucleoproteins can be used to correct genetic defects in skin stem cells of postnatal recessive dystrophic epidermolysis bullosa (RDEB) mice. We developed a method to locally deliver Cas9/sgRNA ribonucleoproteins into the skin of postnatal mice. This method results in rapid gene editing in epidermal stem cells. Using this method, we show that Cas9/sgRNA ribonucleoproteins efficiently excise exon80, which covers the point mutation in our RDEB mouse model, and thus restores the correct localization of the collagen VII protein in vivo. The skin blistering phenotype is also significantly ameliorated after treatment. This study provides an in vivo gene correction strategy using ribonucleoproteins as curative treatment for genetic diseases in skin and potentially in other somatic tissues. PMID:28137859

  9. Early burn wound excision and skin grafting postburn trauma restores in vivo neutrophil delivery to inflammatory lesions

    SciTech Connect

    Tchervenkov, J.I.; Epstein, M.D.; Silberstein, E.B.; Alexander, J.W.

    1988-12-01

    This study assessed the effect of early vs delayed postburn wound excision and skin grafting on the in vivo neutrophil delivery to a delayed-type hypersensitivity (DTH) reaction and a bacterial skin lesion (BSL). Male Lewis rats were presensitized to keyhole-limpet hemocyanin. Group 1 comprised sham controls. Groups 2 through 4 were given a 30% 3 degrees scald burn, but the burn wounds were excised, and skin was grafted on days 1, 3, and 7, respectively, after the burn. Group 5 comprised burn controls. Twelve days after burn trauma, all rats were injected at different intervals (during a 24-hour period) with a trio of intradermal injections of keyhole-limpet hemocyanin, Staphylococcus aureus 502A, and saline at different sites. In vivo neutrophil delivery to these dermal lesions was determined by injecting indium in 111 oxyquinoline-labeled neutrophils isolated from similarly treated groups of rats. Neutrophil delivery to DTH and BSL lesions was restored to normal by excision and skin grafting of the burn wound one day after burn trauma. Waiting three days after burn trauma to excise and skin graft the wound partially, but not completely, restored the in vivo neutrophil delivery to DTH and BSL lesions. Waiting one week to excise and skin graft a burn wound resulted in no improvement in neutrophil delivery to DTH and BSL dermal lesions. It was concluded that burn wound excision and skin grafting immediately after burn trauma restored in vivo neutrophil delivery to a BSL and DTH dermal lesion. This may, in part, explain the beneficial effect of early aggressive burn wound debridement in patients with burn injuries.

  10. Neoplastic alterations induced in mammalian skin following mancozeb exposure using in vivo and in vitro models.

    PubMed

    Tyagi, Shilpa; George, Jasmine; Singh, Richa; Bhui, Kulpreet; Shukla, Yogeshwer

    2011-03-01

    Mancozeb, ethylene(bis)dithiocarbamate fungicides, has been well documented in the literature as a multipotent carcinogen, but the underlying mechanism remains unrevealed. Thus, mancozeb has been selected in this study with the objective to decipher the molecular mechanism that culminates in carcinogenesis. We employed two-dimensional gel electrophoresis and mass spectrometry to generate a comparative proteome profile of control and mancozeb (200 mg/kg body weight) exposed mouse skin. Although many differentially expressed proteins were found, among them, two significantly upregulated proteins, namely, S100A6 (Calcyclin) and S100A9 (Calgranulin-B), are known markers of keratinocyte differentiation and proliferation, which suggested their role in mancozeb-induced neoplastic alterations. Therefore, we verified these alterations in the human system by using HaCaT cells as an in vitro model for human skin keratinocyte carcinogenesis. Upregulation of these two proteins upon mancozeb (0.5 μg/mL) exposure in HaCaT cells indicated its neoplastic potential in human skin also. This potential was confirmed by increase in number of colonies in colony formation and anchorage-independent growth assays. Modulation of S100A6/S100A9 targets, elevated phosphorylation of extracellular signal regulated kinase (ERK1/2), Elk1, nuclear factor- kappa B and cell division cycle 25 C phosphatase, and cyclin D1 and cyclooxygenase-2 upregulation was seen. In addition, PD98059 (ERK1/2 inhibitor) reduced cell proliferation induced by mancozeb, confirming the involvement of ERK1/2 signaling. Conclusively, we herein present the first report asserting that the mechanism involving S100A6 and S100A9 regulated ERK1/2 signaling underlies the mancozeb-induced neoplastic potential in human skin.

  11. Use of fractional laser microablation and ultrasound to facilitate the delivery of gold nanoparticles into skin in vivo

    NASA Astrophysics Data System (ADS)

    Terentyuk, G. S.; Genina, Elina A.; Bashkatov, A. N.; Ryzhova, M. V.; Tsyganova, N. A.; Chumakov, D. S.; Khlebtsov, B. N.; Sazonov, A. A.; Dolotov, L. E.; Tuchin, Valerii V.; Khlebtsov, Nikolai G.; Inozemtseva, O. A.

    2012-06-01

    The delivery of gold nanoparticles (nanocages coated with a layer of silicon dioxide (40/20 nm)) dispersed in the solution (glycerol + polyethylene glycol-400, 1 : 1) into the skin tissue is studied experimentally in vivo. From the data of optical coherence tomography and histochemical analysis it follows that simple application of suspension of nanoparticles is not efficient enough for delivery of the particles into the skin as a result of passive diffusion. It is shown that fractional laser microablation of skin before the application of the suspension, followed by the topical treatment by ultrasound allows penetration through the epidermis layer and delivery of nanoparticles into dermis and hypodermis

  12. Use of fractional laser microablation and ultrasound to facilitate the delivery of gold nanoparticles into skin in vivo

    SciTech Connect

    Terentyuk, G S; Genina, Elina A; Bashkatov, A N; Ryzhova, M V; Tsyganova, N A; Chumakov, D S; Khlebtsov, B N; Sazonov, A A; Dolotov, L E; Tuchin, Valerii V; Khlebtsov, Nikolai G; Inozemtseva, O A

    2012-06-30

    The delivery of gold nanoparticles (nanocages coated with a layer of silicon dioxide (40/20 nm)) dispersed in the solution (glycerol + polyethylene glycol-400, 1 : 1) into the skin tissue is studied experimentally in vivo. From the data of optical coherence tomography and histochemical analysis it follows that simple application of suspension of nanoparticles is not efficient enough for delivery of the particles into the skin as a result of passive diffusion. It is shown that fractional laser microablation of skin before the application of the suspension, followed by the topical treatment by ultrasound allows penetration through the epidermis layer and delivery of nanoparticles into dermis and hypodermis.

  13. In vivo visualization of aromatase in animals and humans

    PubMed Central

    Biegon, Anat

    2015-01-01

    Aromatase catalyzes the last and obligatory step in the biosynthesis of estrogens across species. In vivo visualization of aromatase can be performed using positron emission tomography (PET) with radiolabeled aromatase inhibitors such as [11C]vorozole. PET studies in rats, monkeys and healthy human subjects demonstrate widespread but heterogeneous aromatase availability in brain and body, which appears to be regulated in a species, sex and region-specific manner. Thus, aromatase availability is high in brain amygdala and in ovaries of all species examined to date, with males demonstrating higher levels than females in all comparable organs. However, the highest concentrations of aromatase in the human brain are found in specific nuclei of the thalamus while the highest levels in rats and monkeys are found in the amygdala. Regional brain aromatase availability is increased by androgens and inhibited by nicotine. Future studies may improve diagnosis and treatment in brain disorders and cancers overexpressing aromatase. PMID:26456904

  14. Effect of Enhancers on in vitro and in vivo Skin Permeation and Deposition of S-Methyl-L-Methionine.

    PubMed

    Kim, Ki Taek; Kim, Ji Su; Kim, Min-Hwan; Park, Ju-Hwan; Lee, Jae-Young; Lee, WooIn; Min, Kyung Kuk; Song, Min Gyu; Choi, Choon-Young; Kim, Won-Serk; Oh, Hee Kyung; Kim, Dae-Duk

    2017-03-10

    S-methyl-L-methionine (SMM), also known as vitamin U, is commercially available as skin care cosmetic products for its wound healing and photoprotective effects. However, the low skin permeation expected of SMM due to its hydrophilic nature with a log P value of -3.3, has not been thoroughly addressed. The purpose of this study thus was to evaluate the effect of skin permeation enhancers on the skin permeation/deposition of SMM. Among the enhancers tested for the in vitro skin permeation and deposition of SMM, oleic acid showed the most significant enhancing effect. Moreover, the combination of oleic acid and ethanol further enhanced in vitro permeation and deposition of SMM through hairless mouse skin. Furthermore, the combination of oleic acid and ethanol significantly increased the in vivo deposition of SMM in the epidermis/dermis for 12 hr, which was high enough to exert a therapeutic effect. Therefore, based on the in vitro and in vivo studies, the combination of oleic acid and ethanol was shown to be effective in improving the topical skin delivery of SMM, which may be applied in the cosmetic production process for SMM.

  15. Skin targeted lipid vesicles as novel nano-carrier of ketoconazole: characterization, in vitro and in vivo evaluation.

    PubMed

    Guo, Fang; Wang, Jinping; Ma, Man; Tan, Fengping; Li, Nan

    2015-04-01

    Liposomal carriers for topical drug delivery have been studied since the 1980s and have evoked a considerable interest. However, the conventional liposomes do not deeply penetrate into the skin and remain confined to the outer layer of SC. In order to increase skin targeting of ketoconazole (KCZ), a hydrophobic broad-spectrum antifungal agent, this study describes novel lipid vesicles as nano-carriers for topical delivery. In this paper, lipid vesicular systems including conventional liposomes (CL), ethosomes, deformable liposomes (DL) and ethanol-containing deformable liposomes (DEL) were prepared as nano-carriers for KCZ, respectively. Sodium dodecyl sulfate [SDS, 0.08 % (W/V)] was used as edge activator for DL and DEL preparation. Characterization of the vesicles was based on particle size, zeta potential, entrapment efficiency and transmission electron microscopy (TEM). In addition, in vitro permeation profile was obtained using vertical diffusion Franz cells by porcine skin. The in vivo accumulation of KCZ was also evaluated in rat skin. Confocal microscopy was performed to visualize the penetration of fluorescently labeled vesicles into skin. All of the lipid vesicles showed almost spherical structures with low polydispersity index (PDI < 0.3) and nano-metric size (no more than 160 nm). The results demonstrated that DEL dramatically improved both in vitro and in vivo skin deposition compared to the CLs (P < 0.05), which was further confirmed by confocal laser scanning microscopy study. In vivo pharmacodynamic studies showed DEL improved antifungal activity against Candida albicans in shorter duration of time. Therefore, based on present study, the novel nano-carrier DEL capable of enhancing skin target effect and forming a micro drug-depot could serve as an effective skin targeting delivery for KCZ as an anti-fungal agent in local therapy.

  16. In vivo study of age-related changes in the optical properties of the skin.

    PubMed

    Calin, Mihaela Antonina; Parasca, S V

    2010-03-01

    The optical properties of the skin (absorption coefficient, scattering coefficient, refractive index) may serve to characterize the skin and are important for correct light dosimetry in many optical diagnostic procedures and laser treatments especially photodynamic therapy and laser therapy. We determined in vivo the optical properties of tissues near the wrist, elbow and knee in subjects of different ages using diffuse reflectance spectroscopy, having in view the establishment of laser system types for the laser treatment of posttraumatic lesions in subjects of different ages. Diffuse reflection of light from biological tissue is due to the variation in refractive index of tissular and cellular components and the surrounding medium and depends on the wavelength of the incident optical radiation. The diffuse reflectance spectrum of the tissues tested showed two maxima localized at lamda(M1) is approximately 610 nm and lambda(M2) is approximately 675 nm. Laser systems which emit radiation at these wavelengths are not efficient for the treatment of joints, regardless of the subject's age. The deep tissues have a strong absorption in the range 630-700 nm, which indicates that for treating posttraumatic lesions we can use laser systems such as the He-Ne laser, the GaAlAs laser, and the InGaAlAs laser. Using Kramers-Kronig analysis of the diffuse reflectance spectra, the optical parameters n(omega) and k(omega) were determined. The age-dependent changes in these optical parameters of tissue must be taken into consideration and the use of laser treatments or optical diagnosis methods must be based on a knowledge of these properties and of the optical radiation parameters.

  17. In Vivo Assessment of Clobetasol Propionate-Loaded Lecithin-Chitosan Nanoparticles for Skin Delivery

    PubMed Central

    Şenyiğit, Taner; Sonvico, Fabio; Rossi, Alessandra; Tekmen, Işıl; Santi, Patrizia; Colombo, Paolo; Nicoli, Sara; Özer, Özgen

    2016-01-01

    The aim of this work was to assess in vivo the anti-inflammatory efficacy and tolerability of clobetasol propionate (CP) loaded lecithin/chitosan nanoparticles incorporated into chitosan gel for topical application (CP 0.005%). As a comparison, a commercial cream (CP 0.05% w/w), and a sodium deoxycholate gel (CP 0.05% w/w) were also evaluated. Lecithin/chitosan nanoparticles were prepared by self-assembling of the components obtained by direct injection of soybean lecithin alcoholic solution containing CP into chitosan aqueous solution. Nanoparticles obtained had a particle size around 250 nm, narrow distribution (polydispersity index below 0.2) and positive surface charge, provided by a superficial layer of the cationic polymer. The nanoparticle suspension was then loaded into a chitosan gel, to obtain a final CP concentration of 0.005%. The anti-inflammatory activity was evaluated using carrageenan-induced hind paw edema test on Wistar rats, the effect of formulations on the barrier property of the stratum corneum were determined using transepidermal water loss measurements (TEWL) and histological analysis was performed to evaluate the possible presence of morphological changes. The results obtained indicate that nanoparticle-in-gel formulation produced significantly higher edema inhibition compared to other formulations tested, although it contained ten times less CP. TEWL measurements also revealed that all formulations have no significant disturbance on the barrier function of skin. Furthermore, histological analysis of rat abdominal skin did not show morphological tissue changes nor cell infiltration signs after application of the formulations. Taken together, the present data show that the use of lecithin/chitosan nanoparticles in chitosan gel as a drug carrier significantly improves the risk-benefit ratio as compared with sodium-deoxycholate gel and commercial cream formulations of CP. PMID:28035957

  18. In vivo confocal microscopy of the human cornea

    PubMed Central

    Jalbert, I; Stapleton, F; Papas, E; Sweeney, D F; Coroneo, M

    2003-01-01

    Aims: To describe the optics of in vivo confocal microscopy, its advantages over previous methods, and to summarise the literature that arose from its use for the observation of the human cornea. A critical review of the clinical usefulness of this new technology for the corneal examination is undertaken. Methods: Confocal microscopes obtain increased resolution by limiting the illumination and observation systems to a single point. Rapid scanning is used to reconstruct a full field of view and allows for “real time” viewing. Results: Coronal sections of the in situ epithelium, Bowman’s membrane, stroma, and endothelium can be visualised at a resolution of 1–2 μm. A backscattered light intensity curve allows objective measurements of sublayer thickness and corneal haze to be taken. In vivo confocal microscopy is therefore particularly useful in the areas of infective keratitis, corneal dystrophies, refractive surgery, and contact lens wear, where it aids in differential diagnosis and detection of subtle short and long term changes. Real time endothelial cell assessment can also be performed. Conclusion: Because of their ability to visualise living tissue at cellular levels, confocal microscopes have proved useful additions to the current clinical tools. PMID:12543757

  19. Investigation of normal human skin tissue and acupuncture points of human skin tissue using fiberoptical FTIR spectroscopy

    NASA Astrophysics Data System (ADS)

    Brooks, Angelique L.; Bruch, Reinhard F.; Afanasyeva, Natalia I.; Kolyakov, Sergei F.; Butvina, Leonid N.; Ma, Lixing

    1998-06-01

    An innovative spectroscopic diagnostic method has been developed for investigation of different regions of normal human skin tissue. This new method is a combination of Fourier transform IR fiberoptic evanescent wave (FTIR-FEW) spectroscopy and fiber optic techniques for the middle IR (MIR) wavelength range. The fiber optical sensors we have used are characterized by low optical losses and high flexibility for remote analysis. Our fiber optical accessories and method allows for direct interaction of the skin tissue with the fiber probe and can be utilized with a diversity of standard commercial Fourier transform spectrometers. The FTIR-FEW technique, using nontoxic unclad fibers in the attenuated total reflection regime, is suitable for noninvasive, fast, sensitive investigations of normal skin in vivo for various medical diagnostics applications including studies of acupuncture points. Here we present the first data on IR spectra of skin tissue in vivo for normal skin and several acupuncture points in the range of 1300 to 1800 cm-1 and 2600 to 4000 cm-1.

  20. Electrode-Skin contact impedance: In vivo measurements on an ovine model

    NASA Astrophysics Data System (ADS)

    Nguyen, D. T.; Kosobrodov, R.; Barry, M. A.; Chik, W.; Jin, C.; Oh, T. I.; Thiagalingam, A.; McEwan, A.

    2013-04-01

    The problem of electrical impedance between the skin and the electrode is an on-going challenge in bio-electronics. This is particularly true in the case of Electrical Impedance Tomography (EIT), which uses a large number of skin-contact electrodes and is very sensitive to noise. In the present article, contact impedance is measured and compared for a range of electrodes placed on the thorax of an ovine model. The study has been approved by the Westmead Hospital Animal Ethics Committee. The electrode models that were employed in the research are Ag/AgCl electrodes (E1), commonly used for ECG and EIT measurements in both humans and animal models, stainless steel crocodile clips (E2), typically used on animal models, and novel multi-point dry electrodes in two modifications: bronze plated (E3) and nickel plated (E4). Further, since the contact impedance is mostly attributed to the acellular outer layer of the skin, in our experiment, we attempted to study the effect of this layer by comparing the results when the skin is intact and when electrodes are introduced underneath the skin through small cuts. This boundary effect was assessed by comparison of measurements obtained during E2 skin surface contact, and sub-cutaneous contact (E5). Twelve gauge intradermal needles were also tested as an electrode (E6). The full impedance spectrum, from 500 Hz to 300 kHz, was recorded, analysed and compared. As expected, the contact impedance in the more invasive cases, i.e the electrodes under the skin, is significantly lower than in the non-invasive cases. At the frequency of 50 kHz which is commonly used in lung EIT acquisition, electrodes E3, E4 and E6 demonstrated contact impedance of less than 200 Ω, compared to more than 400 Ω measured for electrodes E1, E2 and E5. In conclusion, the novel multipoint electrodes proved to be best suited for EIT purposes, because they are non-invasive and have lower contact impedance than Ag/AgCl and crocodile clips, in both invasive and

  1. Singlet oxygen induced advanced glycation end-product photobleaching of in vivo human fingertip autofluorescence

    NASA Astrophysics Data System (ADS)

    Deng, Bin; Simental, Anabel; Lutz, Patrick; Shaheen, George; Chaiken, Joseph

    2012-01-01

    Nonenzymatic glycation and oxidation of ubiquitous proteins in vivo leads to irreversible formation of advanced glycation end products (AGEs). Due to their relatively long half life and low clearance rate AGEs tend to accumulate within static tissues and the circulatory system. Spectra obtained using 830 nm near-infrared (NIR) excitation suggest that the so-called "autofluorescence" from all tissues has a finite number of sources but the fact that senior and diabetic subjects produce more than other members of the general population suggests that a significant portion of the total autofluorescence from all sources originates from AGEs. Using pentosidine generated in a reaction mixture as described by Monnier as representative, an in vitro study unveiled very similar fluorescence and photobleaching pattern as observed for autofluorescence in vivo. A series of oxygen, air and argon purging experiments on the pentosidine-generating reaction mixture suggests that pentosidine is a singlet oxygen sensitizer and secondary reactions between the pentosidine itself and/or other fluorophores and the photosensitized singlet oxygen explain the observed photobleaching. Ab initio Gaussian calculations on pentosidine reveal the existence of low-lying triplet excited states required for the sensitization of ground state oxygen. A commercially available product known as singlet oxygen sensor green (SOSG) that specifically serves as a singlet oxygen detection reagent confirms the generation of singlet oxygen from NIR irradiated pentosidine trimixture. This study provides one definite chemical mechanism for understanding in vivo human skin autofluorescence and photobleaching.

  2. In vitro-to-in vivo correlation of the skin penetration, liver clearance and hepatotoxicity of caffeine.

    PubMed

    Gajewska, M; Paini, A; Sala Benito, J V; Burton, J; Worth, A; Urani, C; Briesen, H; Schramm, K-W

    2015-01-01

    This work illustrates the use of Physiologically-Based Toxicokinetic (PBTK) modelling for the healthy Caucasian population in in vitro-to-in vivo correlation of kinetic measures of caffeine skin penetration and liver clearance (based on literature experiments), as well as dose metrics of caffeine-induced measured HepaRG toxicity. We applied a simple correlation factor to quantify the in vitro and in vivo differences in the amount of caffeine permeated through the skin and concentration-time profiles of caffeine in the liver. We developed a multi-scale computational approach by linking the PBTK model with a Virtual Cell-Based Assay to relate an external oral and dermal dose with the measured in vitro HepaRG cell viability. The results revealed higher in vivo skin permeation profiles than those determined in vitro using identical exposure conditions. Liver clearance of caffeine derived from in vitro metabolism rates was found to be much slower than the optimised in vivo clearance with respect to caffeine plasma concentrations. Finally, HepaRG cell viability was shown to remain almost unchanged for external caffeine doses of 5-400 mg for both oral and dermal absorption routes. We modelled single exposure to caffeine only.

  3. Instrument for near infrared emission spectroscopic probing of human fingertips in vivo

    NASA Astrophysics Data System (ADS)

    Chaiken, J.; Deng, Bin; Bussjager, Rebecca J.; Shaheen, George; Rice, David; Stehlik, Dave; Fayos, John

    2010-03-01

    We present instrumentation for probing of volar side fingertip capillary beds with free space coupled near infrared light while collecting Raman, Rayleigh, and Mie scattered light as well as fluorescence. Fingertip skin capillary beds are highly vascularized relative to other tissues and present a desirable target for noninvasive probing of blood. But human hands and fingers in particular are also highly idiosyncratic body parts requiring specific apparatus to allow careful and methodical spectoscopic probing. The apparatus includes means for precise and reproducible placement of the tissues relative to the optical aperture. Appropriate means are provided for applying and maintaining pressure to keep surface tissues immobile during experiments while obtaining the desired blood content and flow. Soft matter, e.g., skin, extrudes into the aperture in response to any applied pressure, e.g., to keep the tissue in registration with the optical system, so the position, contact area, pressure, and force are continuously measured and recorded to produce feedback for an actuator applying force and to discern the compliance of the test subject. The compliance strongly affects the reliability of the measurement and human factors must be adequately managed in the case of in vivo probing. The apparatus produces reproducible observations and measurements that allow consistent probing of the tissues of a wide range of skin types.

  4. Instrument for near infrared emission spectroscopic probing of human fingertips in vivo.

    PubMed

    Chaiken, J; Deng, Bin; Bussjager, Rebecca J; Shaheen, George; Rice, David; Stehlik, Dave; Fayos, John

    2010-03-01

    We present instrumentation for probing of volar side fingertip capillary beds with free space coupled near infrared light while collecting Raman, Rayleigh, and Mie scattered light as well as fluorescence. Fingertip skin capillary beds are highly vascularized relative to other tissues and present a desirable target for noninvasive probing of blood. But human hands and fingers in particular are also highly idiosyncratic body parts requiring specific apparatus to allow careful and methodical spectroscopic probing. The apparatus includes means for precise and reproducible placement of the tissues relative to the optical aperture. Appropriate means are provided for applying and maintaining pressure to keep surface tissues immobile during experiments while obtaining the desired blood content and flow. Soft matter, e.g., skin, extrudes into the aperture in response to any applied pressure, e.g., to keep the tissue in registration with the optical system, so the position, contact area, pressure, and force are continuously measured and recorded to produce feedback for an actuator applying force and to discern the compliance of the test subject. The compliance strongly affects the reliability of the measurement and human factors must be adequately managed in the case of in vivo probing. The apparatus produces reproducible observations and measurements that allow consistent probing of the tissues of a wide range of skin types.

  5. Bio-synthesis of gold nanoparticles by human epithelial cells, in vivo.

    PubMed

    Larios-Rodriguez, E; Rangel-Ayon, C; Castillo, S J; Zavala, G; Herrera-Urbina, R

    2011-09-02

    Healthy epithelial cells, in vivo, have the ability to synthesize gold nanoparticles when aqueous tetrachloroauric acid is made to react with human skin. Neither a reducing agent nor a protecting chemical is needed for this bio-synthesis method. The first indication of gold nanoparticle formation is the staining of the skin, which turns deep purple. Stereoscopic optical micrographs of human skin tissue in contact with aqueous tetrachloroauric acid clearly show the staining of the epithelial cells. The UV-Vis spectrum of these epithelial cells shows an absorption band with a maximum at 553 nm. This absorption peak is within the wavelength region where the surface plasmon resonance (SPR) band of aqueous colloidal gold exhibits a maximum. Transmission electron micrographs show that gold nanoparticles synthesized by epithelial cells have sizes between 1 and 100 nm. The electron diffraction pattern of these nanoparticles reveals a crystalline structure whose interplanar distances correspond to fcc metallic gold. Transmission electron micrographs of ultra-thin (70 nm thick) slices of epithelial cells clearly and undoubtedly demonstrate that gold nanoparticles are inside the cell. According to high resolution transmission electron micrographs of intracellular single gold nanoparticles, they have the shape of a polyhedron.

  6. Noncontacting diffuse VIS-NIR spectroscopy of human skin for evaluation of skin type and time-dependent microcirculation

    NASA Astrophysics Data System (ADS)

    Schmidt, Wolf-Dieter; Fassler, Dieter; Zimmermann, Gabi; Liebold, Kristin; Wollina, Uwe

    2000-11-01

    Spectroscopic investigations of the VIS-NIR range allow the objective determination of pigmentation, blood microcirculation and water content of human skin. Non- contacting in vivo measurements of the human skin of 50 volunteers reflect the clinical skin type well. Our correlation analysis yields that the red/infrared spectral range can be used for a determination of skin type. The observed strong spectral variations within the same group of skin type are likely based on the high biological variability of human skin and subjective clinically observed skin type. Therefore it can be useful to measure the full spectral range and to calculate a non-observed skin score with multivariate spectral methods. By multivariate analysis a correct classification of remittance spectra can be obtained. Time- depending spectral variations of dermal microcirculation can be measured at defined locations of the body, for instance the dynamics of oxygenation or blood volume in the skin of the fingertip. The cardial, pulmonal and vasomotoric waves of the micro- and macrocirculation are clearly visible at different wavelengths. The spectroscopic informations are important as an objective measure for the skin type evaluation, the penetration behavior of pharmaca, laser surgery, and therapy.

  7. Signal and depth enhancement for in vivo flow cytometer measurement of ear skin by optical clearing agents

    PubMed Central

    Ding, Yimin; Wang, Jing; Fan, Zhichao; Wei, Dan; Shi, Rui; Luo, Qingming; Zhu, Dan; Wei, Xunbin

    2013-01-01

    The in vivo flow cytometry (IVFC) has shown a great potential for detecting circulating tumor cells quantitatively in the bloodstream. However, the detection depth suffers from the strong light scattering of tissue. In this study, an innovative ear skin optical clearing agent (ESOCA) is employed to improve the signal quality of the IVFC. Our results show that compared with commonly used glycerol, topical application of ESOCA can enhance the transmittance of rat ear significantly in vivo. The labeled red blood cells can be detected by the IVFC with higher signal quality and greater detection depth. This study is very helpful for potential tumor metastasis studies by the IVFC in deep tissues. PMID:24298412

  8. Migration and penetration of a fluorescent textile dye into the skin--in vivo versus in vitro methods.

    PubMed

    Meinke, Martina; Abdollahnia, Mandana; Gähr, Frank; Platzek, Thomas; Sterry, Wolfram; Lademann, Jürgen

    2009-09-01

    The amount of textile dye migration from the textile and penetration into the skin is relevant when assessing the risk of textile dyes. In this paper, in vivo methods were developed using a harmless textile dye with a strong fluorescence and were then compared with in vitro methods. For the in vivo method, the textile was applied to the lower back of six volunteers wearing the textile 12 h and to the lower back of 12 volunteers during 30 min active sport. The maximum skin absorption of 55 +/- 17 ng/cm(2) was obtained in the group engaged in sports. The in vitro methods, which involved the application of the textile to the pig ear skin, was shown to yield similar results to the 12 h in vivo group (31.2 +/- 9.6 ng/cm(2) vs 27 +/- 14 ng/cm(2)). The migration of the textiles into artificial sweat resulted in approximately 20 microg/cm(2). The disadvantage of such textile extract applications on pig ear skin is discussed. It could be demonstrated that the absorption of the dye is strongly correlated to the amount of sweat, whereas the contact time was less important.

  9. Thermal effusivity of human skin by photoacoustic technique

    NASA Astrophysics Data System (ADS)

    Varela-Najera, Jose B.; Cordova-Fraga, Teodor; Vargas-Luna, Miguel; Gutierrez-Juarez, Gerardo

    2000-05-01

    In this work, we show a particular setup, which is based on the conventional photoacoustic cell, to measure thermal effusivity of human skin in-vivo and in-situ. We measure the changes of thermal effusivity due to the absorption of sunscreen into the skin and these values are compared with those from an adjacent sample of clean skin. This experiment was performed on a volunteer's forearm and stainless steel as the thermally thin absorption surface. The values for this parameter are in good agreement with those reported in the literature. Besides the measurements described above, with the same setup we got the thermal effusivity of the sunscreen itself as a reference parameter. R

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

    PubMed

    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.

  11. In Vivo Characterization of Human APOA5 Haplotypes

    SciTech Connect

    Ahituv, Nadav; Akiyama, Jennifer; Chapman-Helleboid, Audrey; Fruchart, Jamila; Pennacchio, Len A.

    2006-10-01

    Increased plasma triglycerides concentrations are an independent risk factor for cardiovascular disease. Numerous studies support a reproducible genetic association between two minor haplotypes in the human apolipoprotein A5 gene (APOA5) and increased plasma triglyceride concentrations. We thus sought to investigate the effect of these minor haplotypes (APOA5*2 and APOA5*3) on ApoAV plasma levels through the precise insertion of single-copy intact APOA5 haplotypes at a targeted location in the mouse genome. While we found no difference in the amount of human plasma ApoAV in mice containing the common APOA5*1 and minor APOA5*2 haplotype, the introduction of the single APOA5*3 defining allele (19W) resulted in 3-fold lower ApoAV plasma levels consistent with existing genetic association studies. These results indicate that S19W polymorphism is likely to be functional and explain the strong association of this variant with plasma triglycerides supporting the value of sensitive in vivo assays to define the functional nature of human haplotypes.

  12. Antibacterial Evaluation of Synthetic Thiazole Compounds In Vitro and In Vivo in a Methicillin-Resistant Staphylococcus aureus (MRSA) Skin Infection Mouse Model

    PubMed Central

    Mohammad, Haroon; Cushman, Mark; Seleem, Mohamed N.

    2015-01-01

    The emergence of community-associated methicillin-resistant Staphylococcus aureus (MRSA), including strains resistant to current antibiotics, has contributed to an increase in the number of skin infections reported in humans in recent years. New therapeutic options are needed to counter this public health challenge. The aim of the present study was to examine the potential of thiazole compounds synthesized by our research group to be used topically to treat MRSA skin and wound infections. The broth microdilution method confirmed that the lead thiazole compound and four analogues are capable of inhibiting MRSA growth at concentrations as low as 1.3 μg/mL. Additionally, three compounds exhibited a synergistic relationship when combined with the topical antibiotic mupirocin against MRSA in vitro via the checkerboard assay. Thus the thiazole compounds have potential to be used alone or in combination with mupirocin against MRSA. When tested against human keratinocytes, four derivatives of the lead compound demonstrated an improved toxicity profile (were found to be non-toxic up to a concentration of 20 μg/mL). Utilizing a murine skin infection model, we confirmed that the lead compound and three analogues exhibited potent antimicrobial activity in vivo, with similar capability as the antibiotic mupirocin, as they reduced the burden of MRSA present in skin wounds by more than 90%. Taken altogether, the present study provides important evidence that these thiazole compounds warrant further investigation for development as novel topical antimicrobials to treat MRSA skin infections. PMID:26536129

  13. Antibacterial Evaluation of Synthetic Thiazole Compounds In Vitro and In Vivo in a Methicillin-Resistant Staphylococcus aureus (MRSA) Skin Infection Mouse Model.

    PubMed

    Mohammad, Haroon; Cushman, Mark; Seleem, Mohamed N

    2015-01-01

    The emergence of community-associated methicillin-resistant Staphylococcus aureus (MRSA), including strains resistant to current antibiotics, has contributed to an increase in the number of skin infections reported in humans in recent years. New therapeutic options are needed to counter this public health challenge. The aim of the present study was to examine the potential of thiazole compounds synthesized by our research group to be used topically to treat MRSA skin and wound infections. The broth microdilution method confirmed that the lead thiazole compound and four analogues are capable of inhibiting MRSA growth at concentrations as low as 1.3 μg/mL. Additionally, three compounds exhibited a synergistic relationship when combined with the topical antibiotic mupirocin against MRSA in vitro via the checkerboard assay. Thus the thiazole compounds have potential to be used alone or in combination with mupirocin against MRSA. When tested against human keratinocytes, four derivatives of the lead compound demonstrated an improved toxicity profile (were found to be non-toxic up to a concentration of 20 μg/mL). Utilizing a murine skin infection model, we confirmed that the lead compound and three analogues exhibited potent antimicrobial activity in vivo, with similar capability as the antibiotic mupirocin, as they reduced the burden of MRSA present in skin wounds by more than 90%. Taken altogether, the present study provides important evidence that these thiazole compounds warrant further investigation for development as novel topical antimicrobials to treat MRSA skin infections.

  14. Melanin and blood concentration in human skin studied by multiple regression analysis: experiments.

    PubMed

    Shimada, M; Yamada, Y; Itoh, M; Yatagai, T

    2001-09-01

    Knowledge of the mechanism of human skin colour and measurement of melanin and blood concentration in human skin are needed in the medical and cosmetic fields. The absorbance spectrum from reflectance at the visible wavelength of human skin increases under several conditions such as a sunburn or scalding. The change of the absorbance spectrum from reflectance including the scattering effect does not correspond to the molar absorption spectrum of melanin and blood. The modified Beer-Lambert law is applied to the change in the absorbance spectrum from reflectance of human skin as the change in melanin and blood is assumed to be small. The concentration of melanin and blood was estimated from the absorbance spectrum reflectance of human skin using multiple regression analysis. Estimated concentrations were compared with the measured one in a phantom experiment and this method was applied to in vivo skin.

  15. Melanin and blood concentration in human skin studied by multiple regression analysis: experiments

    NASA Astrophysics Data System (ADS)

    Shimada, M.; Yamada, Y.; Itoh, M.; Yatagai, T.

    2001-09-01

    Knowledge of the mechanism of human skin colour and measurement of melanin and blood concentration in human skin are needed in the medical and cosmetic fields. The absorbance spectrum from reflectance at the visible wavelength of human skin increases under several conditions such as a sunburn or scalding. The change of the absorbance spectrum from reflectance including the scattering effect does not correspond to the molar absorption spectrum of melanin and blood. The modified Beer-Lambert law is applied to the change in the absorbance spectrum from reflectance of human skin as the change in melanin and blood is assumed to be small. The concentration of melanin and blood was estimated from the absorbance spectrum reflectance of human skin using multiple regression analysis. Estimated concentrations were compared with the measured one in a phantom experiment and this method was applied to in vivo skin.

  16. New Enlightenment of Skin Cancer Chemoprevention through Phytochemicals: In Vitro and In Vivo Studies and the Underlying Mechanisms

    PubMed Central

    Singh, Madhulika; Suman, Shankar; Shukla, Yogeshwer

    2014-01-01

    Skin cancer is still a major cause of morbidity and mortality worldwide. Skin overexposure to ultraviolet irradiations, chemicals, and several viruses has a capability to cause severe skin-related disorders including immunosuppression and skin cancer. These factors act in sequence at various steps of skin carcinogenesis via initiation, promotion, and/or progression. These days cancer chemoprevention is recognized as the most hopeful and novel approach to prevent, inhibit, or reverse the processes of carcinogenesis by intervention with natural products. Phytochemicals have antioxidant, antimutagenic, anticarcinogenic, and carcinogen detoxification capabilities thereby considered as efficient chemopreventive agents. Considerable efforts have been done to identify the phytochemicals which may possibly act on one or several molecular targets that modulate cellular processes such as inflammation, immunity, cell cycle progression, and apoptosis. Till date several phytochemicals in the light of chemoprevention have been studied by using suitable skin carcinogenic in vitro and in vivo models and proven as beneficial for prevention of skin cancer. This revision presents a comprehensive knowledge and the main molecular mechanisms of actions of various phytochemicals in the chemoprevention of skin cancer. PMID:24757666

  17. New Enlightenment of Skin Cancer Chemoprevention through Phytochemicals: In Vitro and In Vivo Studies and the Underlying Mechanisms.

    PubMed

    Singh, Madhulika; Suman, Shankar; Shukla, Yogeshwer

    2014-01-01

    Skin cancer is still a major cause of morbidity and mortality worldwide. Skin overexposure to ultraviolet irradiations, chemicals, and several viruses has a capability to cause severe skin-related disorders including immunosuppression and skin cancer. These factors act in sequence at various steps of skin carcinogenesis via initiation, promotion, and/or progression. These days cancer chemoprevention is recognized as the most hopeful and novel approach to prevent, inhibit, or reverse the processes of carcinogenesis by intervention with natural products. Phytochemicals have antioxidant, antimutagenic, anticarcinogenic, and carcinogen detoxification capabilities thereby considered as efficient chemopreventive agents. Considerable efforts have been done to identify the phytochemicals which may possibly act on one or several molecular targets that modulate cellular processes such as inflammation, immunity, cell cycle progression, and apoptosis. Till date several phytochemicals in the light of chemoprevention have been studied by using suitable skin carcinogenic in vitro and in vivo models and proven as beneficial for prevention of skin cancer. This revision presents a comprehensive knowledge and the main molecular mechanisms of actions of various phytochemicals in the chemoprevention of skin cancer.

  18. Dynamic longitudinal investigation of individual nerve endings in the skin of anesthetized mice using in vivo two-photon microscopy

    NASA Astrophysics Data System (ADS)

    Yuryev, Mikhail; Khiroug, Leonard

    2012-04-01

    Visualization of individual cutaneous nerve endings has previously relied on laborious procedures of tissue excision, fixation, sectioning and staining for light or electron microscopy. We present a method for non-invasive, longitudinal two-photon microscopy of single nerve endings within the skin of anesthetized transgenic mice. Besides excellent signal-to-background ratio and nanometer-scale spatial resolution, this method offers time-lapse ``movies'' of pathophysiological changes in nerve fine structure over minutes, hours, days or weeks. Structure of keratinocytes and dermal matrix is visualized simultaneously with nerve endings, providing clear landmarks for longitudinal analysis. We further demonstrate feasibility of dissecting individual nerve fibers with infra-red laser and monitoring their degradation and regeneration. In summary, our excision-free optical biopsy technique is ideal for longitudinal microscopic analysis of animal skin and skin innervations in vivo and can be applied widely in preclinical models of chronic pain, allergies, skin cancers and a variety of dermatological disorders.

  19. Comparison of two methods for noninvasive determination of carotenoids in human and animal skin: Raman spectroscopy versus reflection spectroscopy.

    PubMed

    Darvin, Maxim E; Sandhagen, Carl; Koecher, Wolfgang; Sterry, Wolfram; Lademann, Juergen; Meinke, Martina C

    2012-07-01

    Based on compelling in vivo and in vitro studies on human skin, carotenoids are thought to be of great interest as powerful antioxidants acting to prevent free-radical-induced damages, including premature skin ageing and the development of skin diseases such as cancer. Among the available techniques that are suitable for noninvasive determination of carotenoids in human skin, are resonance Raman spectroscopy (RRS) and reflection spectroscopy (RS). For RS, a LED-based miniaturized spectroscopic system (MSS) was developed for noninvasive measurement of carotenoids in human skin. The optimization and subsequent calibration of the MSS was performed with the use of RRS. A strong correlation between the carotenoid concentration determined by the RS and for the RRS system was achieved for human skin in vivo (R = 0.88) and for bovine udder skin in vitro (R = 0.81).

  20. Human skin: an independent peripheral endocrine organ.

    PubMed

    Zouboulis, C C

    2000-01-01

    The historical picture of the endocrine system as a set of discrete hormone-producing organs has been substituted by organs regarded as organized communities in which the cells emit, receive and coordinate molecular signals from established endocrine organs, other distant sources, their neighbors, and themselves. In this wide sense, the human skin and its tissues are targets as well as producers of hormones. Although the role of hormones in the development of human skin and its capacity to produce and release hormones are well established, little attention has been drawn to the ability of human skin to fulfil the requirements of a classic endocrine organ. Indeed, human skin cells produce insulin-like growth factors and -binding proteins, propiomelanocortin derivatives, catecholamines, steroid hormones and vitamin D from cholesterol, retinoids from diet carotenoids, and eicosanoids from fatty acids. Hormones exert their biological effects on the skin through interaction with high-affinity receptors, such as receptors for peptide hormones, neurotransmitters, steroid hormones and thyroid hormones. In addition, the human skin is able to metabolize hormones and to activate and inactivate them. These steps are overtaken in most cases by different skin cell populations in a coordinated way indicating the endocrine autonomy of the skin. Characteristic examples are the metabolic pathways of the corticotropin-releasing hormone/propiomelanocortin axis, steroidogenesis, vitamin D, and retinoids. Hormones exhibit a wide range of biological activities on the skin, with major effects caused by growth hormone/insulin-like growth factor-1, neuropeptides, sex steroids, glucocorticoids, retinoids, vitamin D, peroxisome proliferator-activated receptor ligands, and eicosanoids. At last, human skin produces hormones which are released in the circulation and are important for functions of the entire organism, such as sex hormones, especially in aged individuals, and insulin-like growth

  1. Differentiating intratumoral melanocytes from Langerhans cells in nonmelanocytic pigmented skin tumors in vivo by label-free third-harmonic generation microscopy

    NASA Astrophysics Data System (ADS)

    Weng, Wei-Hung; Liao, Yi-Hua; Tsai, Ming-Rung; Wei, Ming-Liang; Huang, Hsin-Yi; Sun, Chi-Kuang

    2016-07-01

    Morphology and distribution of melanocytes are critical imaging information for the diagnosis of melanocytic lesions. However, how to image intratumoral melanocytes noninvasively in pigmented skin tumors is seldom investigated. Third-harmonic generation (THG) is shown to be enhanced by melanin, whereas high accuracy has been demonstrated using THG microscopy for in vivo differential diagnosis of nonmelanocytic pigmented skin tumors. It is thus desirable to investigate if label-free THG microscopy was capable to in vivo identify intratumoral melanocytes. In this study, histopathological correlations of label-free THG images with the immunohistochemical images stained with human melanoma black (HMB)-45 and cluster of differentiation 1a (CD1a) were made. The correlation results indicated that the intratumoral THG-bright dendritic-cell-like signals were endogenously derived from melanocytes rather than Langerhans cells (LCs). The consistency between THG-bright dendritic-cell-like signals and HMB-45 melanocyte staining showed a kappa coefficient of 0.807, 84.6% sensitivity, and 95% specificity. In contrast, a kappa coefficient of -0.37, 21.7% sensitivity, and 30% specificity were noted between the THG-bright dendritic-cell-like signals and CD1a staining for LCs. Our study indicates the capability of noninvasive label-free THG microscopy to differentiate intratumoral melanocytes from LCs, which is not feasible in previous in vivo label-free clinical-imaging modalities.

  2. In vivo imaging of dermal collagen in skin burn by collagen-sensitive second-harmonic-generation microscopy

    NASA Astrophysics Data System (ADS)

    Yasui, Takeshi; Tanaka, Ryosuke; Hase, Eiji; Fukushima, Shu-ichiro; Araki, Tsutomu

    2013-02-01

    Optical assessment of skin burns is possible with second-harmonic-generation (SHG) microscopy due to its high sensitivity to thermal denaturation of collagen molecules. In contrast to previous studies that were performed using excised tissue specimens ex vivo, in this study, we demonstrated in vivo observation of dermal collagen fibers in living rat burn models with SHG microscopy. We confirmed that changes in SHG vanishing patterns in the SHG images depended on the burn degree. The results imply that SHG microscopy can be used as a low-invasiveness, highly quantitative tool for skin burn assessment.

  3. Effect of recombinant interleukin-12 on murine skin regeneration and cell dynamics using in vivo multimodal microscopy

    PubMed Central

    Li, Joanne; Bower, Andrew J.; Vainstein, Vladimir; Gluzman-Poltorak, Zoya; Chaney, Eric J.; Marjanovic, Marina; Basile, Lena A.; Boppart, Stephen A.

    2015-01-01

    Interleukin-12 (IL-12) is a pro-inflammatory cytokine known for its role in immunity, and previous studies have shown that IL-12 provides mitigation of radiation injury. In this study, we utilize a multimodal microscopy system equipped with second harmonic generation (SHG) and fluorescence lifetime imaging microscopy (FLIM) to examine the effect of IL-12 on collagen structure and cellular metabolic activity in vivo during skin wound healing. This preliminary study illustrates the highly dynamic and heterogeneous in vivo microenvironment of the wounded skin. In addition, results suggest that IL-12 triggers a significantly more rapid and greater cellular metabolic response in the wounded animals. These results can elucidate insights into the response mechanism of IL-12 in both wound healing and acute radiation syndrome. PMID:26600994

  4. Attenuation Coefficient Estimation of the Healthy Human Thyroid In Vivo

    NASA Astrophysics Data System (ADS)

    Rouyer, J.; Cueva, T.; Portal, A.; Yamamoto, T.; Lavarello, R.

    Previous studies have demonstrated that attenuation coefficients can be useful towards characterizing thyroid tissues. In this work, ultrasonic attenuation coefficients were estimated from healthy human thyroids in vivo using a clinical scanner. The selected subjects were five young, healthy volunteers (age: 26 ± 6 years old, gender: three females, two males) with no reported history of thyroid diseases, no palpable thyroid nodules, no smoking habits, and body mass index less than 30 kg/m2. Echographic examinations were conducted by a trained sonographer using a SonixTouch system (Ultrasonix Medical Corporation, Richmond, BC) equipped with an L14-5 linear transducer array (nominal center frequency of 10 MHz, transducer footprint of 3.8 cm). Radiofrequency data corresponding to the collected echographic images in both transverse and longitudinal views were digitized at a sampling rate of 40 MHz and processed with Matlab codes (MathWorks, Natick, MA) to estimate attenuation coefficients using the spectral log difference method. The estimation was performed using an analysis bandwidth spanning from 4.0 to 9.0 MHz. The average value of the estimated ultrasonic attenuation coefficients was equal to 1.34 ± 0.15 dB/(cm.MHz). The standard deviation of the estimated average attenuation coefficient across different volunteers suggests a non-negligible inter-subject variability in the ultrasonic attenuation coefficient of the human thyroid.

  5. In Vivo Persistence of Human Rhinoviruses in Immunosuppressed Patients

    PubMed Central

    Engelmann, Ilka; Dewilde, Anny; Lazrek, Mouna; Batteux, Mathilde; Hamissi, Aminati; Yakoub-Agha, Ibrahim; Hober, Didier

    2017-01-01

    Several species of the genus Enterovirus cause persistent infections in humans. Human rhinovirus (HRV) infections are generally self-limiting but occasionally persistent infections have been described. This study aimed to identify persistent HRV infections and investigate the clinical and virologic characteristics of patients with persistent infections. From January 2012 to March 2015, 3714 respiratory specimens from 2608 patients were tested for respiratory viruses by using a multiplex reverse transcription–polymerase chain reaction. A retrospective study was performed. Patients with at least two specimens positive for HRV/enterovirus taken 45 days or longer apart were identified and the HRV/enteroviruses were typed. Patients with persistent infection were compared to patients with reinfection and patients with cleared infection. Phylogenetic analysis of the viral protein(VP)4/VP2 region was performed. 18 patients with persistent HRV/enterovirus infection were identified. Minimum median duration of persistence was 92 days (range 50–455 days). All but one patients with persistence were immunosuppressed. Immunosuppression and hematologic disorders were more frequent in patients with persistence (n = 18) than in patients with reinfection (n = 33) and with cleared infection (n = 25) (p = 0.003 and p = 0.001, respectively). In conclusion, this retrospective study identified HRV persistence in vivo which occurred mainly in immunosuppressed patients. PMID:28151988

  6. Tissue engineered human tracheas for in vivo implantation.

    PubMed

    Baiguera, Silvia; Jungebluth, Phillip; Burns, Alan; Mavilia, Carmelo; Haag, Johannes; De Coppi, Paolo; Macchiarini, Paolo

    2010-12-01

    Two years ago we performed the first clinical successful transplantation of a fully tissue engineered trachea. Despite the clinically positive outcome, the graft production took almost 3 months, a not feasible period of time for patients with the need of an urgent transplantation. We have then improved decellularization process and herein, for the first time, we completely describe and characterize the obtainment of human tracheal bioactive supports. Histological and molecular biology analysis demonstrated that all cellular components and nuclear material were removed and quantitative PCR confirmed it. SEM analysis revealed that the decellularized matrices retained the hierarchical structures of native trachea, and biomechanical tests showed that decellularization approach did not led to any influence on tracheal morphological and mechanical properties. Moreover immunohistological staining showed the preservation of angiogenic factors and angiogenic assays demonstrated that acellular human tracheal scaffolds exert an in vitro chemo-active action and induce strong in vivo angiogenic response (CAM analysis). We are now able to obtained, in a short and clinically useful time (approximately 3 weeks), a bioengineered trachea that is structurally and mechanically similar to native trachea, which exert chemotactive and pro-angiogenic properties and which could be successfully used for clinical tissue engineered airway clinical replacements.

  7. Raman measurement of carotenoid composition in human skin

    NASA Astrophysics Data System (ADS)

    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.

  8. Photoprotection of human skin beyond ultraviolet radiation.

    PubMed

    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.

  9. SKI knockdown inhibits human melanoma tumor growth in vivo.

    PubMed

    Chen, Dahu; Lin, Qiushi; Box, Neil; Roop, Dennis; Ishii, Shunsuke; Matsuzaki, Koichi; Fan, Tao; Hornyak, Thomas J; Reed, Jon A; Stavnezer, Ed; Timchenko, Nikolai A; Medrano, Estela E

    2009-12-01

    The SKI protein represses the TGF-beta tumor suppressor pathway by associating with the Smad transcription factors. SKI is upregulated in human malignant melanoma tumors in a disease-progression manner and its overexpression promotes proliferation and migration of melanoma cells in vitro. The mechanisms by which SKI antagonizes TGF-beta signaling in vivo have not been fully elucidated. Here we show that human melanoma cells in which endogenous SKI expression was knocked down by RNAi produced minimal orthotopic tumor xenograft nodules that displayed low mitotic rate and prominent apoptosis. These minute tumors exhibited critical signatures of active TGF-beta signaling including high levels of nuclear Smad3 and p21(Waf-1), which are not found in the parental melanomas. To understand how SKI promotes tumor growth we used gain- and loss-of-function approaches and found that simultaneously to blocking the TGF-beta-growth inhibitory pathway, SKI promotes the switch of Smad3 from tumor suppression to oncogenesis by favoring phosphorylations of the Smad3 linker region in melanoma cells but not in normal human melanocytes. In this context, SKI is required for preventing TGF-beta-mediated downregulation of the oncogenic protein c-MYC, and for inducing the plasminogen activator inhibitor-1, a mediator of tumor growth and angiogenesis. Together, the results indicate that SKI exploits multiple regulatory levels of the TGF-beta pathway and its deficiency restores TGF-beta tumor suppressor and apoptotic activities in spite of the likely presence of oncogenic mutations in melanoma tumors.

  10. Evaluation of dermal-epidermal skin equivalents ('composite-skin') of human keratinocytes in a collagen-glycosaminoglycan matrix(Integra artificial skin).

    PubMed

    Kremer, M; Lang, E; Berger, A C

    2000-09-01

    Integra artificial skin (Integra LifeSciences Corp., Plainsboro, NJ, USA) is a dermal template consisting of bovine collagen, chondroitin-6-sulphate and a silastic membrane manufactured as Integra. This product has gained widespread use in the clinical treatment of third degree burn wounds and full thickness skin defects of different aetiologies. The product was designed to significantly reduce the time needed to achieve final wound closure in the treatment of major burn wounds, to optimise the sparse autologous donor skin resources and to improve the durable mechanical quality of the skin substitute. The clinical procedure requires two stages. The first step creates a self neodermis, the second creates a self epidermis on the neodermis. However, it is desirable to cover major burn wounds early in a single step by a skin substitute consisting of a dermal equivalent seeded in vitro with autologous keratinocytes ('composite-skin') out of which a full thickness skin develops in vivo.The goal of this experimental study was to develop a method to integrate human keratinocytes in homogeneous distribution and depth into Integra Artificial Skin. The seeded cell-matrix composites were grafted onto athymic mice in order to evaluate their potential to reconstitute a human epidermis in vivo. We were able to demonstrate that the inoculated human keratinocytes reproducibly displayed a homogeneous pattern of distribution, adherence, proliferation and confluence. The cell-matrix composites grafted in this model exhibited good wound adherence, complete healing, minor wound contraction and had the potential to reconstitute an elastic, functional and durable human skin. Histologically we were able to show that the inoculated human keratinocytes in vivo colonised the matrix in a histomorphologically characteristic epidermal pattern (keratomorula, keratinocyte bubbling) and developed a persisting, stratified, keratinising epidermis which immunohistologically proved to be of human

  11. Biopharmaceutical profile of hydrogels containing pranoprofen-loaded PLGA nanoparticles for skin administration: In vitro, ex vivo and in vivo characterization.

    PubMed

    Abrego, Guadalupe; Alvarado, Helen; Souto, Eliana B; Guevara, Bessy; Bellowa, Lyda Halbaut; Garduño, Maria Luisa; Garcia, María Luisa; Calpena, Ana C

    2016-03-30

    Pranoprofen (PF)-loaded nanoparticles (PF-F1NPs and PF-F2NPs) have been formulated into blank hydrogels (HG_PF-F1NPs and HG_PF-F1NPs) or into hydrogels composed of 3% azone (HG_PF-F1NPs-Azone and HG_PF-F2NPs-Azone), as innovative strategy to improve the biopharmaceutical profile of the selected non-steroidal anti-inflammatory drug (Pranoprofen, PF) for topical application. The purpose of this approach has been to increase the contact of PF with the skin, improve its retention in deeper layers, thus enhancing its anti-inflammatory and analgesic effects. The physicochemical characterization of the developed hydrogels showed a non-Newtonian behaviour, typical of semi-solid formulations for skin administration, with sustained release profile. The results obtained from ex vivo skin human permeation and in vivo anti-inflammatory efficacy studies suggest that topical application of HG_PF-F2NPs has been more effective in the treatment of oedema on the skin' surface in comparison to other hydrogels. No signs of skin irritancy have been detected for all the semi-solid formulations containing 0% or 3% azone.

  12. Pyrimidine dimer formation and repair in human skin

    SciTech Connect

    Sutherland, B.M.; Harber, L.C.; Kochevar, I.E.

    1980-09-01

    Cyclobutyl pyrimidine dimers have been detected in the DNA of human skin following in vivo irradiation with suberythermal doses of ultraviolet (UV) radiation from FS-20 sun lamp fluorescent tubes. Dimers were assayed by treatment of extracted DNA with Micrococus luteus UV-specific endonuclease, alkaline agarose electrophoresis, and ethidum bromide staining. This technique, in contrast to conventional dimer assays, can be used with nonradioactive DNA and is optimal at low UV light doses. These data suggest that some dimer disappearance by excision repair occurs within 20 min of UV irradiation and that photoreactivation of dimers can make a contribution to the total repair process.

  13. Penetration of chlorhexidine into human skin.

    PubMed

    Karpanen, T J; Worthington, T; Conway, B R; Hilton, A C; Elliott, T S J; Lambert, P A

    2008-10-01

    This study evaluated a model of skin permeation to determine the depth of delivery of chlorhexidine into full-thickness excised human skin following topical application of 2% (wt/vol) aqueous chlorhexidine digluconate. Skin permeation studies were performed on full-thickness human skin using Franz diffusion cells with exposure to chlorhexidine for 2 min, 30 min, and 24 h. The concentration of chlorhexidine extracted from skin sections was determined to a depth of 1,500 microm following serial sectioning of the skin using a microtome and analysis by high-performance liquid chromatography. Poor penetration of chlorhexidine into skin following 2-min and 30-min exposures to chlorhexidine was observed (0.157 +/- 0.047 and 0.077 +/- 0.015 microg/mg tissue within the top 100 microm), and levels of chlorhexidine were minimal at deeper skin depths (less than 0.002 microg/mg tissue below 300 microm). After 24 h of exposure, there was more chlorhexidine within the upper 100-microm sections (7.88 +/- 1.37 microg/mg tissue); however, the levels remained low (less than 1 microg/mg tissue) at depths below 300 microm. There was no detectable penetration through the full-thickness skin. The model presented in this study can be used to assess the permeation of antiseptic agents through various layers of skin in vitro. Aqueous chlorhexidine demonstrated poor permeation into the deeper layers of the skin, which may restrict the efficacy of skin antisepsis with this agent. This study lays the foundation for further research in adopting alternative strategies for enhanced skin antisepsis in clinical practice.

  14. Utility of a human-mouse xenograft model and in vivo near-infrared fluorescent imaging for studying wound healing.

    PubMed

    Shanmugam, Victoria K; Tassi, Elena; Schmidt, Marcel O; McNish, Sean; Baker, Stephen; Attinger, Christopher; Wang, Hong; Shara, Nawar; Wellstein, Anton

    2015-12-01

    To study the complex cellular interactions involved in wound healing, it is essential to have an animal model that adequately mimics the human wound microenvironment. Currently available murine models are limited because wound contraction introduces bias into wound surface area measurements. The purpose of this study was to demonstrate utility of a human-mouse xenograft model for studying human wound healing. Normal human skin was harvested from elective abdominoplasty surgery, xenografted onto athymic nude (nu/nu) mice, and allowed to engraft for 3 months. The graft was then wounded using a 2-mm punch biopsy. Wounds were harvested on sequential days to allow tissue-based markers of wound healing to be followed sequentially. On the day of wound harvest, mice were injected with XenoLight RediJect cyclooxygenase-2 (COX-2) probe and imaged according to package instructions. Immunohistochemistry confirms that this human-mouse xenograft model is effective for studying human wound healing in vivo. Additionally, in vivo fluorescent imaging for inducible COX-2 demonstrated upregulation from baseline to day 4 (P = 0·03) with return to baseline levels by day 10, paralleling the reepithelialisation of the wound. This human-mouse xenograft model, combined with in vivo fluorescent imaging provides a useful mechanism for studying molecular pathways of human wound healing.

  15. Quantifying the mechanical properties of human skin to optimise future microneedle device design.

    PubMed

    Groves, R B; Coulman, S A; Birchall, J C; Evans, S L

    2012-01-01

    Microneedle devices are a promising minimally invasive means of delivering drugs/vaccines across or into the skin. However, there is currently a diversity of microneedle designs and application methods that have, primarily, been intuitively developed by the research community. To enable the rational design of optimised microneedle devices, a greater understanding of human skin biomechanics under small deformations is required. This study aims to develop a representative stratified model of human skin, informed by in vivo data. A multilayer finite element model incorporating the epidermis, dermis and hypodermis was established. This was correlated with a series of in-vivo indentation measurements, and the Ogden material coefficients were optimised using a material parameter extraction algorithm. The finite element simulation was subsequently used to model microneedle application to human skin before penetration and was validated by comparing these predictions with the in-vivo measurements. Our model has provided an excellent tool to predict micron-scale human skin deformation in vivo and is currently being used to inform optimised microneedle designs.

  16. Topical vehicles based on natural surfactant/fatty alcohols mixed emulsifier: The influence of two polyols on the colloidal structure and in vitro/in vivo skin performance.

    PubMed

    Savic, Snezana; Weber, Christian; Tamburic, Slobodanka; Savic, Miroslav; Müller-Goymann, Christel

    2009-06-01

    There is a growing need for in-depth research into new skin- and environment-friendly surfactants, such as alkylpolyglucosides. The aim of this study was to assess whether, to which extent and by what mechanism the two commonly used hydrophilic excipients, propylene glycol (PG) and glycerol (GL), affect the colloidal structure of emulsions formed by a natural mixed emulsifier, cetearyl glucoside and cetearyl alcohol. Furthermore, the study was concerned with the effect of these changes on in vitro permeation profiles of two model drugs (diclofenac sodium and caffeine) and in vivo skin performance of the test samples. The results have shown that the emulsion vehicles consisted of a complex colloidal structure of lamellar liquid crystalline and lamellar gel crystalline type. PG addition produced a stronger hydrophilic lamellar gel phase than GL, which was independent on the model drug used. PG-containing vehicles have revealed a considerable amount of interlamellar PG/water mixture, with incorporated drug. In vitro permeation data obtained using artificial skin constructs (ASC) confirmed the relationship between rheological profiles of vehicles and the extent of skin delivery. Higher permeation profiles of both drugs from PG-containing formulations coincided with a higher increase in transepidermal water loss observed in in vivo study on human volunteers, which confirms the penetration/permeation enhancer effect of PG. It also indicates the existence of the vehicle/ASC interactions analogous to those between the vehicle and the skin, thus affirming the use of ASC as a reliable tool for permeation studies. Contrary to the effect of PG, the results obtained with GL suggest that it may have a permeation-retarding rather than a permeation-enhancing effect in topical vehicles of this type.

  17. Analysis of in vivo somatic mutations in normal human cells

    SciTech Connect

    Gupta, P.K.; Sahota, A.; Boyadjiev, S.A.

    1994-09-01

    We have used the APRT locus located at 16q24.3 to study the nature of loss of heterozygosity (LOH) in human T lymphocytes in vivo. T lymphocytes were isolated from blood from APRT (+/{minus}) obligated heterozygotes with known germline mutations. The cells were immediatley placed in culture medium containing 100 {mu}M 2,6-diaminopurine (DAP) to select for drug-resistant clones ({minus}/{minus}) already present. These clones were first examined using polymorphic CA microsatellite repeat markers D16S303 and D16S305 that are distal and proximal to APRT, respectively. The retention of heterozygosity of these markers is suggestive of minor changes in the APRT gene, the exact nature of which were determined by DNA sequencing. Nineteen out of 70 DAP-resistant clones from one heterozygote showed APRT sequence changes. The loss of heterozygosity of markers D16S303 and D16S305 in the remaining clones suggests LOH involving multilocus chromosomal events. These clones were then sequentially typed using additional CA repeat markers proximal and distal to APRT. The extent of LOH in these clones was found to vary from <5 cM to almost the entire 16q arm. Preliminary results suggest that there are multiple sites along the chromosome from which LOH proceeds distally in these clones. Cytogenetic analysis of 10 clones suggested mitotic recombination in 9 and deletion in one. Studies are in progress to further characterize the molecular mechanisms of LOH.

  18. Diclofenac acid nanocrystals as an effective strategy to reduce in vivo skin inflammation by improving dermal drug bioavailability.

    PubMed

    Pireddu, Rosa; Caddeo, Carla; Valenti, Donatella; Marongiu, Francesca; Scano, Alessandra; Ennas, Guido; Lai, Francesco; Fadda, Anna Maria; Sinico, Chiara

    2016-07-01

    In this work a diclofenac acid nanosuspension formulation was produced as a novel approach for the treatment of skin inflammation. Drug nanocrystals, prepared by the wet media milling technique and stabilized using Poloxamer 188, were characterized by different techniques: scanning electron microscopy, differential scanning calorimetry, X-ray powder diffractometry, Fourier transform infrared spectroscopy and photon correlation spectroscopy. The ability of nanocrystals to improve dermal drug bioavailability was investigated ex vivo by using Franz diffusion vertical cells and mouse skin, in comparison with both diclofenac acid coarse suspensions and a commercial formulation. The topical anti-inflammatory activity of the drug nanosuspension was assessed in vivo by testing its effect compared to common inflammatory endpoints: i.e. the inhibition of chemically induced oedema and leucocyte infiltration (reflected in myeloperoxidase activity). Following the milling procedure, diclofenac nanocrystals exhibited a mean diameter of approximately 279nm, a low polydispersity index (∼0.17) and maintained the same polymorphic form of the starting bulk powder. When the drug nanosuspension was applied on the mouse skin it produced a higher accumulation of diclofenac in the skin compared to both the coarse suspensions and the commercial formulation, as demonstrated by ex vivo transdermal delivery experiments. Moreover, the nanosuspension provided an in vivo oedema inhibition of 50%, which was not statistically different from the commercial formulation. On the contrary, the nanosuspension showed a higher inhibition of myeloperoxidase activity in the damaged tissue (86%) than the commercial formulation (16%).

  19. Epithelial and stromal developmental patterns in a novel substitute of the human skin generated with fibrin-agarose biomaterials.

    PubMed

    Carriel, Víctor; Garzón, Ingrid; Jiménez, Jose-María; Oliveira, Ana-Celeste-Ximenes; Arias-Santiago, Salvador; Campos, Antonio; Sánchez-Quevedo, Maria-Carmen; Alaminos, Miguel

    2012-01-01

    Development of human skin substitutes by tissue engineering may offer new therapeutic alternatives to the use of autologous tissue grafts. For that reason, it is necessary to investigate and develop new biocompatible biomaterials that support the generation of a proper human skin construct. In this study, we generated a novel model of bioengineered human skin substitute using human cells obtained from skin biopsies and fibrin-agarose biomaterials and we evaluated this model both at the ex vivo and the in vivo levels. Once the dermal fibroblasts and the epithelial keratinocytes were isolated and expanded in culture, we used fibrin-agarose scaffolds for the development of a full-thickness human skin construct, which was evaluated after 1, 2, 3 and 4 weeks of development ex vivo. The skin substitutes were then grafted onto immune-deficient nude mice and analyzed at days 10, 20, 30 and 40 postimplantation using transmission electron microscopy, histochemistry and immunofluorescence. The results demonstrated that the fibrin-agarose artificial skin had adequate biocompatibility and proper biomechanical properties. A proper development of both the bioengineered dermis and epidermis was found after 30 days in vivo, although the tissues kept ex vivo and those implanted in the animal model for 10 or 20 days showed lower levels of differentiation. In summary, our model of fibrin-agarose skin equivalent was able to reproduce the structure and histological architecture of the native human skin, especially after long-term in vivo implantation, suggesting that these tissues could reproduce the native skin.

  20. Millimeter wave dosimetry of human skin.

    PubMed

    Alekseev, S I; Radzievsky, A A; Logani, M K; Ziskin, M C

    2008-01-01

    To identify the mechanisms of biological effects of mm waves it is important to develop accurate methods for evaluating absorption and penetration depth of mm waves in the epidermis and dermis. The main characteristics of mm wave skin dosimetry were calculated using a homogeneous unilayer model and two multilayer models of skin. These characteristics included reflection, power density (PD), penetration depth (delta), and specific absorption rate (SAR). The parameters of the models were found from fitting the models to the experimental data obtained from measurements of mm wave reflection from human skin. The forearm and palm data were used to model the skin with thin and thick stratum corneum (SC), respectively. The thin SC produced little influence on the interaction of mm waves with skin. On the contrary, the thick SC in the palm played the role of a matching layer and significantly reduced reflection. In addition, the palmar skin manifested a broad peak in reflection within the 83-277 GHz range. The viable epidermis plus dermis, containing a large amount of free water, greatly attenuated mm wave energy. Therefore, the deeper fat layer had little effect on the PD and SAR profiles. We observed the appearance of a moderate SAR peak in the therapeutic frequency range (42-62 GHz) within the skin at a depth of 0.3-0.4 mm. Millimeter waves penetrate into the human skin deep enough (delta = 0.65 mm at 42 GHz) to affect most skin structures located in the epidermis and dermis.

  1. Healing and evaluating guinea pig skin incision after surgical suture and laser tissue by welding using in vivo Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Alimova, A.; Sriramoju, V.; Chakraverty, R.; Muthukattil, R.; Alfano, R. R.

    2010-02-01

    Changes in collagen in the wound during the healing process of guinea pig skin following surgical incisions and LTW was evaluated using in vivo, using Raman spectroscopy. Raman spectroscopy provided information regarding the internal structure of the proteins. After the incisions were closed either by suturing or by LTW the ratio of the Raman peaks of the amide III (1247 cm-1) band to a peak at 1326 cm-1 used to evaluate the progression of collagen deposition. Histopathology was used as the gold standard. LTW skin demonstrated better healing than sutured skin, exhibiting minimal hyperkeratosis, minimal collagen deposition, near-normal surface contour, and minimal loss of dermal appendages. This work is important to plastic surgery.

  2. In vivo metabolic response of glucose to dichloroacetate in humans.

    PubMed

    Brown, J A; Gore, D C

    1996-03-01

    Hyperglycemia is common in severely ill patients and is related principally to an increase in glucose production. Dichloroacetate (DCA), which is known to increase the rate of pyruvate oxidation, has been shown to lower plasma glucose concentrations in normal fasting subjects and in diabetics and thus may be efficacious in treating stress induced hyperglycemia. However, the mechanism by which DCA lowers the plasma glucose concentration in humans has not been elucidated. To examine the human in vivo metabolic alterations induced by DCA, six fasting volunteers were infused with 6,6-D2-glucose and indirect calorimetry was performed prior to and following DCA administration. Glucose, lactate, and alanine net balance across the leg were also quantitated. Following DCA administration, plasma glucose concentrations decreased by 9% due to a proportional decrease in the rate of glucose production (P < 0.05). DCA had no affect on glucose clearance or leg net balance; however, the rate of glucose oxidation increased by 24% from baseline (P < 0.05). This increase in glucose oxidation without a compensatory change in peripheral glucose consumption suggests an improved efficiency in peripheral glucose utilization induced by DCA. Plasma concentrations of lactate and alanine were also lowered by DCA (56% for lactate, 66% for alanine, P < 0.05) without a significant alteration in leg net balance. These results suggest that DCA may decrease gluconeogenesis by limiting the availability of the precursor substrates lactate and alanine. Thus dichloroacetate may be an appropriate alternative to insulin in correcting mild elevations in plasma glucose concentrations. Furthermore, DCA may be especially effective in severely ill patients where hyperglycemia is largely due to increases in gluconeogenesis.

  3. In vivo effects of rosiglitazone in a human neuroblastoma xenograft

    PubMed Central

    Cellai, I; Petrangolini, G; Tortoreto, M; Pratesi, G; Luciani, P; Deledda, C; Benvenuti, S; Ricordati, C; Gelmini, S; Ceni, E; Galli, A; Balzi, M; Faraoni, P; Serio, M; Peri, A

    2010-01-01

    Background: Neuroblastoma (NB) is the most common extra-cranial solid tumour in infants. Unfortunately, most children present with advanced disease and have a poor prognosis. There is in vitro evidence that the peroxisome proliferator-activated receptor γ (PPARγ) might be a target for pharmacological intervention in NB. We have previously demonstrated that the PPARγ agonist rosiglitazone (RGZ) exerts strong anti-tumoural effects in the human NB cell line, SK-N-AS. The aim of this study was to evaluate whether RGZ maintains its anti-tumoural effects against SK-N-AS NB cells in vivo. Methods and results: For this purpose, tumour cells were subcutaneously implanted in nude mice, and RGZ (150 mg kg−1) was administered by gavage daily for 4 weeks. At the end of treatment, a significant tumour weight inhibition (70%) was observed in RGZ-treated mice compared with control mice. The inhibition of tumour growth was supported by a strong anti-angiogenic activity, as assessed by CD-31 immunostaining in tumour samples. The number of apoptotic cells, as determined by cleaved caspase-3 immunostaining, seemed lower in RGZ-treated animals at the end of the treatment period than in control mice, likely because of the large tumour size observed in the latter group. Conclusions: To our knowledge, this is the first demonstration that RGZ effectively inhibits tumour growth in a human NB xenograft and our results suggest that PPARγ agonists may have a role in anti-tumoural strategies against NB. PMID:20068562

  4. The Genetics of Human Skin Disease

    PubMed Central

    DeStefano, Gina M.; Christiano, Angela M.

    2014-01-01

    The skin is composed of a variety of cell types expressing specific molecules and possessing different properties that facilitate the complex interactions and intercellular communication essential for maintaining the structural integrity of the skin. Importantly, a single mutation in one of these molecules can disrupt the entire organization and function of these essential networks, leading to cell separation, blistering, and other striking phenotypes observed in inherited skin diseases. Over the past several decades, the genetic basis of many monogenic skin diseases has been elucidated using classical genetic techniques. Importantly, the findings from these studies has shed light onto the many classes of molecules and essential genetic as well as molecular interactions that lend the skin its rigid, yet flexible properties. With the advent of the human genome project, next-generation sequencing techniques, as well as several other recently developed methods, tremendous progress has been made in dissecting the genetic architecture of complex, non-Mendelian skin diseases. PMID:25274756

  5. [Physiological features of skin ageing in human].

    PubMed

    Tikhonova, I V; Tankanag, A V; Chemeris, N K

    2013-01-01

    The issue deals with the actual problem of gerontology, notably physiological features of human skin ageing. In the present review the authors have considered the kinds of ageing, central factors, affected on the ageing process (ultraviolet radiation and oxidation stress), as well as the research guidelines of the ageing changes in the skin structure and fuctions: study of mechanical properties, microcirculation, pH and skin thickness. The special attention has been payed to the methods of assessment of skin blood flow, and to results of investigations of age features of peripheral microhemodynamics. The laser Doppler flowmetry technique - one of the modern, noninvasive and extensively used methods for the assessmant of skin blood flow microcirculation system has been expanded in the review. The main results of the study of the ageing changes of skin blood perfusion using this method has been also presented.

  6. Skin-sparing Helical Tomotherapy vs 3D-conformal Radiotherapy for Adjuvant Breast Radiotherapy: In Vivo Skin Dosimetry Study

    SciTech Connect

    Capelle, Lisa; Warkentin, Heather; MacKenzie, Marc; Joseph, Kurian; Gabos, Zsolt; Pervez, Nadeem; Tankel, Keith; Chafe, Susan; Amanie, John; Ghosh, Sunita; Parliament, Matthew; Abdulkarim, Bassam

    2012-08-01

    Purpose: We investigated whether treatment-planning system (TPS)-calculated dose accurately reflects skin dose received for patients receiving adjuvant breast radiotherapy (RT) with standard three-dimensional conformal RT (3D-CRT) or skin-sparing helical tomotherapy (HT). Methods and Materials: Fifty patients enrolled in a randomized controlled trial investigating acute skin toxicity from adjuvant breast RT with 3D-CRT compared to skin-sparing HT, where a 5-mm strip of ipsilateral breast skin was spared. Thermoluminescent dosimetry or optically stimulated luminescence measurements were made in multiple locations and were compared to TPS-calculated doses. Skin dosimetric parameters and acute skin toxicity were recorded in these patients. Results: With HT there was a significant correlation between calculated and measured dose in the medial and lateral ipsilateral breast (r = 0.67, P<.001; r = 0.44, P=.03, respectively) and the medial and central contralateral breast (r = 0.73, P<.001; r = 0.88, P<.001, respectively). With 3D-CRT there was a significant correlation in the medial and lateral ipsilateral breast (r = 0.45, P=.03; r = 0.68, P<.001, respectively); the medial and central contralateral breast (r = 0.62, P=.001; r = 0.86, P<.001, respectively); and the mid neck (r = 0.42, P=.04, respectively). On average, HT-calculated dose overestimated the measured dose by 14%; 3D-CRT underestimated the dose by 0.4%. There was a borderline association between highest measured skin dose and moist desquamation (P=.05). Skin-sparing HT had greater skin homogeneity (homogeneity index of 1.39 vs 1.65, respectively; P=.005) than 3D-CRT plans. HT plans had a lower skin{sub V50} (1.4% vs 5.9%, respectively; P=.001) but higher skin{sub V40} and skin{sub V30} (71.7% vs 64.0%, P=.02; and 99.0% vs 93.8%, P=.001, respectively) than 3D-CRT plans. Conclusion: The 3D-CRT TPS more accurately reflected skin dose than the HT TPS, which tended to overestimate dose received by 14% in patients

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

    PubMed

    Morgan, Marjorie S; Arlian, Larry G; Markey, Michael P

    2013-01-01

    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.

  8. Stokes scattering matrix for human skin.

    PubMed

    Bhandari, Anak; Stamnes, Snorre; Hamre, Børge; Frette, Oyvind; Stamnes, Knut; Stamnes, Jakob J

    2012-11-01

    We use a layered model of normal human skin based on size distributions of polydisperse spherical particles and their complex refractive indices to compute the Stokes scattering matrix at wavelengths in the visible spectral band. The elements of the Stokes scattering matrix are required in a polarized radiative transfer code for a coupled air-tissue system to compute the polarized reflectance and examine how it is dependent on the vertical structure of the inherent optical properties of skin, including the phase matrix. Thus, the elements of the Stokes scattering matrix can be useful for investigating polarization-dependent light propagation in turbid optical media, such as human skin tissue.

  9. The use of ex vivo human skin tissue for genotoxicity testing

    SciTech Connect

    Reus, Astrid A.; Usta, Mustafa; Krul, Cyrille A.M.

    2012-06-01

    As a result of the chemical legislation concerning the registration, evaluation, authorization and restriction of chemicals (REACH), and the Seventh Amendment to the Cosmetics Directive, which prohibits animal testing in Europe for cosmetics, alternative methods for safety evaluation of chemicals are urgently needed. Current in vitro genotoxicity assays are not sufficiently predictive for the in vivo situation, resulting in an unacceptably high number of misleading positives. For many chemicals and ingredients of personal care products the skin is the first site of contact, but there are no in vitro genotoxicity assays available in the skin for additional evaluation of positive or equivocal responses observed in regulatory in vitro genotoxicity assays. In the present study ex vivo human skin tissue obtained from surgery was used for genotoxicity evaluation of chemicals by using the comet assay. Fresh ex vivo human skin tissue was cultured in an air–liquid interface and topically exposed to 20 chemicals, including true positive, misleading positive and true negative genotoxins. Based on the results obtained in the present study, the sensitivity, specificity and accuracy of the ex vivo skin comet assay to predict in vivo genotoxicity were 89%, 90% and 89%, respectively. Donor and experimental variability were mainly reflected in the magnitude of the response and not the difference between the presence and absence of a genotoxic response. The present study indicates that human skin obtained from surgery is a promising and robust model for safety evaluation of chemicals that are in direct contact with the skin. -- Highlights: ► We use human skin obtained from surgery for genotoxicity evaluation of chemicals. ► We use the comet assay as parameter for genotoxicity in ex vivo human skin. ► Sensitivity, specificity and accuracy to predict in vivo genotoxins are determined. ► Sensitivity, specificity and accuracy are 89%, 90% and 90%, respectively. ► The method

  10. In-vivo Stretch of Term Human Fetal Membranes

    PubMed Central

    Joyce, EM; Diaz, P; Tamarkin, S; Moore, R; Strohl, A; Stetzer, B; Kumar, D; Sacks, MS; Moore, JJ

    2015-01-01

    Introduction Fetal membranes (FM) usually fail prior to delivery during term labor, but occasionally fail at preterm gestation, precipitating preterm birth. To understand the FM biomechanical properties underlying these events, study of the baseline in-vivo stretch experienced by the FM is required. This study's objective was to utilize high resolution MRI imaging to determine in-vivo FM stretch. Methods Eight pregnant women (38.4±0.4wks) underwent abdominal-pelvic MRI prior to (2.88±0.83d) caesarean delivery. Software was utilized to determine the total FM in-vivo surface area (SA) and that of its components: placental disc and reflected FM. At delivery, the SA of the disc and FM in the relaxed state were measured. In-vivo (stretched) to delivered SA ratios were calculated. FM fragments were then biaxially stretched to determine the force required to re-stretch the FM back to in-vivo SA. Results Total FM SA, in-vivo vs delivered, was 2135.51±108.47 cm2 vs 842.59±35.86 cm2; reflected FM was 1778.42±107.39 cm2 vs 545.41±22.90 cm2, and disc was 357.10±28.08 cm2 vs 297.18±22.14 cm2. The ratio (in-vivo to in-vitro SA) of reflected FM was 3.26±0.11 and disc was 1.22±0.10. Reflected FM re-stretched to in-vivo SA generated a tension of 72.26N/m, corresponding to approximate pressure of 15.4mmHg. FM rupture occurred at 295.08 ± 31.73N/m corresponding to approximate pressure of 34mmHg. Physiological SA was 70% of that at rupture. Discussion FM are significantly distended in-vivo. FM collagen fibers were rapidly recruited once loaded and functioned near the failure state during in-vitro testing, suggesting that, in-vivo, minimal additional (beyond physiological) stretch may facilitate rapid, catastrophic failure. PMID:26907383

  11. Statistical Properties of Echosignal Obtained from Human Dermis In Vivo

    NASA Astrophysics Data System (ADS)

    Piotrzkowska, Hanna; Litniewski, Jerzy; Nowicki, Andrzej; Szymańska, Elżbieta

    The paper presents the classification of the healthy skin and the skin lesions (basal cell carcinoma and actinic keratosis), basing on the statistical parameters of the envelope of ultrasonic echoes. The envelope was modeled using Rayleigh and non-Rayleigh (K-distribution) statistics. Furthermore, the characteristic parameter of the K-distribution, the effective number of scatterers was investigated. Also the attenuation coefficient was used for the skin lesion assessment.

  12. Skin mechanics measured in vivo using torsion: a new and accurate model more sensitive to age, sex and moisturizing treatment.

    PubMed

    Salter, D C; McArthur, H C; Crosse, J E; Dickens, A D

    1993-10-01

    Summary Measurements of skin mechanics are required to understand better cracking and flaking of the epidermis and loss of 'elasticity'with age in the dermis. Improvements in torsional testing are described here. The resulting data was fitted to algebraic models, the parameters of which can serve both as a concise description of the responses and as a means of relating them to skin structure and physiology. This investigation looks into the suitability of seven such algebraic models. Five of the models examined here appear to be new. Using the commercially available Dia-Stron DTM Torque Meter with our own software, model parameters were studied as indicators of the effects of age and sex in 41 people, and of skin moisturizing treatments in a further 10 people. The two models in the literature were both found to be substantially less accurate and sensitive representations of experimental data than one of the new models proposed here based on the Weibull distribution. This 'WB model'was consistently the one best able to distinguish differences and detect changes which were statistically significant. The WB model appears to be the most powerful and efficient available. Use of this model makes it possible to demonstrate in vivo a statistically significant mechanical difference between male and pre-menopausal female skin using only one parameter (p= 0.0163, with 18 males and 19 females) and to demonstrate a statistically significant mechanical difference between successive decades of age in female skin using only one parameter (p= 0.0124, n= 24). The two parameters of the model most sensitive to skin structure, function and treatment have been combined to form the axes of a 'Skin condition chart'. Any person can be located on this chart at a point indicating their overall skin condition in mechanical terms and any changes in that condition can be clearly demonstrated by movement across the plot.

  13. Human in vivo cutaneous microdialysis: estimation of histamine release in cold urticaria.

    PubMed

    Andersson, T; Wårdell, K; Anderson, C

    1995-09-01

    A novel bioanalytical in vivo sampling technique, cutaneous microdialysis, was used to follow the chronology of skin histamine release in 3 patients with cold urticaria and in 2 healthy volunteers. Laser Doppler perfusion imaging was used simultaneously to monitor the skin circulatory response. Microdialysis samples were collected at 10-min intervals and analysed by radioimmunoassay technique. Fifty minutes after probe insertion, the ventral forearm skin in the area of the dialysis membrane was provoked for 5-15 min with a 25 x 40 mm ice cube covered with plastic foil. In the cold urticaria patients, an up to 80-fold increase of histamine was observed, with peak levels 20-30 min after challenge. Histamine levels then fell to reach "baseline" levels within 50 min. In the healthy subjects, the histamine increase was earlier, less pronounced and of shorter duration. Cutaneous microdialysis and laser Doppler imaging offer new possibilities for the chronological multiparameter assessment of inflammatory skin disorders in vivo.

  14. The E6 Oncoprotein from HPV16 Enhances the Canonical Wnt/β-catenin Pathway in Skin Epidermis in vivo

    PubMed Central

    Bonilla-Delgado, José; Bulut, Gülay; Liu, Xuefeng; Cortés-Malagón, Enoc M.; Schlegel, Richard; Flores-Maldonado, Catalina; Contreras, Rubén G.; Chung, Sang-Hyuk; Lambert, Paul F.; Üren, Aykut; Gariglio, Patricio

    2012-01-01

    The contribution of the Wnt signaling pathway to HPV-induced carcinogenesis is poorly understood. In high-grade dysplastic lesions that are caused by high-risk human papilloma viruses (HR-HPVs), β-catenin is often located in the cell nucleus, which suggests that Wnt pathway may be involved in the development of HPV-related carcinomas. Most of the oncogenic potential of HR-HPVs resides on the E6 protein’s PDZ-binding domain. We hypothesized that the PDZ-binding domain of the HPV16-E6 oncoprotein induces the nuclear accumulation of β-catenin due to its capacity to degrade PDZ-containing cellular targets. To test this hypothesis, we evaluated the staining pattern of β-catenin in the skin epidermis of transgenic mice expressing the full-length E6 oncoprotein (K14E6 mice) and measured LacZ gene expression in K14E6 mice that were crossed with a strain expressing LacZ that was knocked into the Axin2 locus (Axin2+/LacZ mice). Here, we show that the E6 oncoprotein enhances the nuclear accumulation of β-catenin, the accumulation of cellularβ-catenin-responsive genes and the expression of LacZ. None of these effects were observed when a truncated E6 oncoprotein that lacks the PDZ-binding domain was expressed alone (K14E6ΔPDZ mice) or in combination with Axin2+/LacZ. Conversely, co-transfection with either E6 or E6ΔPDZ similarly enhanced canonical Wnt signaling in short-term in vitro assays that utilized a luciferase Wnt/β-catenin/TCF-dependent promoter. We propose that the activation of canonical Wnt signaling could be induced by the HPV16-E6 oncoprotein; however, the participation of the E6 PDZ-binding domain seems to be important in in vivo models only. PMID:22160870

  15. Novel peptides functionally targeting in vivo human lung cancer discovered by in vivo peptide displayed phage screening.

    PubMed

    Lee, Kyoung Jin; Lee, Jae Hee; Chung, Hye Kyung; Choi, Jinhyang; Park, Jaesook; Park, Seok Soon; Ju, Eun Jin; Park, Jin; Shin, Seol Hwa; Park, Hye Ji; Ko, Eun Jung; Suh, Nayoung; Kim, InKi; Hwang, Jung Jin; Song, Si Yeol; Jeong, Seong-Yun; Choi, Eun Kyung

    2015-02-01

    Discovery of the cancer-specific peptidic ligands have been emphasized for active targeting drug delivery system and non-invasive imaging. For the discovery of useful and applicable peptidic ligands, in vivo peptide-displayed phage screening has been performed in this study using a xenograft mouse model as a mimic microenvironment to tumor. To seek human lung cancer-specific peptides, M13 phage library displaying 2.9 × 10(9) random peptides was intravenously injected into mouse model bearing A549-derived xenograft tumor through the tail vein. Then the phages emerged from a course of four rounds of biopanning in the xenograft tumor tissue. Novel peptides were categorized into four groups according to a sequence-homology phylogenicity, and in vivo tumor-targeting capacity of these peptides was validated by whole body imaging with Cy5.5-labeled phages in various cancer types. The result revealed that novel peptides accumulated only in adenocarcinoma lung cancer cell-derived xenograft tissue. For further confirmation of the specific targeting ability, in vitro cell-binding assay and immunohistochemistry in vivo tumor tissue were performed with a selected peptide. The peptide was found to bind intensely to lung cancer cells both in vitro and in vivo, which was efficiently compromised with unlabeled phages in an in vitro competition assay. In conclusion, the peptides specifically targeting human lung cancer were discovered in this study, which is warranted to provide substantive feasibilities for drug delivery and imaging in terms of a novel targeted therapeutics and diagnostics.

  16. Noninvasive In Vivo Imaging to Evaluate Immune Responses and Antimicrobial Therapy against Staphylococcus aureus and USA300 MRSA Skin Infections

    PubMed Central

    Cho, John S.; Zussman, Jamie; Donegan, Niles P.; Irene Ramos, Romela; Garcia, Nairy C.; Uslan, Daniel Z.; Iwakura, Yoichiro; Simon, Scott I.; Cheung, Ambrose L.; Modlin, Robert L.; Kim, Jenny; Miller, Lloyd S.

    2011-01-01

    Staphylococcus aureus skin infections represent a significant public health threat because of the emergence of antibiotic-resistant strains such as methicillin-resistant S. aureus (MRSA). As greater understanding of protective immune responses and more effective antimicrobial therapies are needed, a S. aureus skin wound infection model was developed in which full-thickness scalpel cuts on the backs of mice were infected with a bioluminescent S. aureus (methicillin sensitive) or USA300 community-acquired MRSA strain and in vivo imaging was used to noninvasively monitor the bacterial burden. In addition, the infection-induced inflammatory response was quantified using in vivo fluorescence imaging of LysEGFP mice. Using this model, we found that both IL-1α and IL-1β contributed to host defense during a wound infection, whereas IL-1β was more critical during an intradermal S. aureus infection. Furthermore, treatment of a USA300 MRSA skin infection with retapamulin ointment resulted in up to 85-fold reduction in bacterial burden and a 53% decrease in infection-induced inflammation. In contrast, mupirocin ointment had minimal clinical activity against this USA300 strain, resulting in only a 2-fold reduction in bacterial burden. Taken together, this S. aureus wound infection model provides a valuable preclinical screening method to investigate cutaneous immune responses and the efficacy of topical antimicrobial therapies. PMID:21191403

  17. Reflectance confocal microscopy and dermoscopy for in vivo, non-invasive skin imaging of superficial basal cell carcinoma

    PubMed Central

    GHITA, MIHAELA A.; CARUNTU, CONSTANTIN; ROSCA, ADRIAN E.; KALESHI, HARILLAQ; CARUNTU, ANA; MORARU, LILIANA; DOCEA, ANCA OANA; ZURAC, SABINA; BODA, DANIEL; NEAGU, MONICA; SPANDIDOS, DEMETRIOS A.; TSATSAKIS, ARISTIDIS M.

    2016-01-01

    Superficial basal cell carcinoma (sBCC) is the second most frequent histological type of basal cell carcinoma (BCC), usually requiring a skin biopsy to confirm the diagnosis. It usually appears on the upper trunk and shoulders as erythematous and squamous lesions. Although it has a slow growth and seldom metastasizes, early diagnosis and management are of crucial importance in preventing local invasion and subsequent disfigurement. Dermoscopy is nowadays an indispensable tool for the dermatologist when evaluating skin tumors. Reflectance confocal microscopy (RCM) is a novel imaging technique that allows the non-invasive, in vivo quasi-microscopic morphological and dynamic assessment of superficial skin tumors. Moreover, it offers the advantage of performing infinite repeatable determinations to monitor disease progression and non-surgical treatment for sBCC. Herein, we present three lesions of sBCC evaluated using in vivo and non-invasive imaging techniques, emphasizing the usefulness of combining RCM with dermoscopy for increasing the diagnostic accuracy of sBCC. PMID:27123056

  18. Use of multiphoton tomography and fluorescence lifetime imaging to investigate skin pigmentation in vivo

    NASA Astrophysics Data System (ADS)

    Dancik, Yuri; Favre, Amandine; Loy, Chong Jin; Zvyagin, Andrei V.; Roberts, Michael S.

    2013-02-01

    There is a growing body of literature showing the usefulness of multiphoton tomography (MPT) and fluorescence lifetime imaging for in situ characterization of skin constituents and the ensuing development of noninvasive diagnostic tools against skin diseases. Melanin and pigmentation-associated skin cancers constitute some of the major applications. We show that MPT and fluorescence lifetime imaging can be used to measure changes in cutaneous melanin concentration and that these can be related to the visible skin color. Melanin in the skin of African, Indian, Caucasian, and Asian volunteers is detected on the basis of its emission wavelength and fluorescence lifetimes in solution and in a melanocyte-keratinocyte cell culture. Fluorescence intensity is used to characterize the melanin content and distribution as a function of skin type and depth into the skin (stratum granulosum and stratum basale). The measured fluorescence intensities in given skin types agree with melanin amounts reported by others using biopsies. Our results suggest that spatial distribution of melanin in skin can be studied using MPT and fluorescence lifetime imaging, but further studies are needed to ascertain that the method can resolve melanin amount in smaller depth intervals.

  19. Amplified Mechanically Gated Currents in Distinct Subsets of Myelinated Sensory Neurons following In Vivo Inflammation of Skin and Muscle.

    PubMed

    Weyer, Andy D; O'Hara, Crystal L; Stucky, Cheryl L

    2015-06-24

    Primary afferents are sensitized to mechanical stimuli following in vivo inflammation, but whether sensitization of mechanically gated ion channels contributes to this phenomenon is unknown. Here we identified two populations of murine A fiber-type sensory neurons that display markedly different responses to focal mechanical stimuli of the membrane based on their expression of calcitonin gene-related peptide (CGRP). Following inflammation of the hindpaw, myelinated, CGRP-positive neurons projecting to the paw skin displayed elevated mechanical currents in response to mechanical stimuli. Conversely, muscle inflammation markedly amplified mechanical currents in myelinated, CGRP-negative neurons projecting to muscle. These data show, for the first time, that mechanically gated currents are amplified following in vivo tissue inflammation, and also suggest that mechanical sensitization can occur in myelinated neurons after inflammation.

  20. Efficacy of Lantibiotic Treatment of Staphylococcus aureus-Induced Skin Infections, Monitored by In Vivo Bioluminescent Imaging

    PubMed Central

    Heunis, Tiaan; Smith, Carine; Deane, Shelly

    2016-01-01

    Staphylococcus aureus is a bacterial pathogen responsible for the majority of skin and soft tissue infections. Antibiotics are losing their efficacy as treatment for skin and soft tissue infections as a result of increased resistance in a variety of pathogens, including S. aureus. It is thus imperative to explore alternative antimicrobial treatments to ensure future treatment options for skin and soft tissue infections. A select few lantibiotics, a group of natural defense peptides produced by bacteria, inhibit the growth of numerous clinical S. aureus isolates, including methicillin-resistant strains. In this study, the antimicrobial activities of nisin, clausin, and amyloliquecidin, separately administered, were compared to that of a mupirocin-based ointment, which is commonly used as treatment for S. aureus-induced skin infections. Full-thickness excisional wounds, generated on the dorsal surfaces of mice, were infected with a bioluminescent strain of S. aureus (strain Xen 36). The infections were monitored in real time using in vivo bioluminescent imaging. Lantibiotic treatments significantly reduced the bioluminescence of S. aureus Xen 36 to a level similar to that recorded with mupirocin treatment. Wound closure, however, was more pronounced during lantibiotic treatment. Lantibiotics thus have the potential to be used as an alternative treatment option for S. aureus-induced skin infections. PMID:27067340

  1. Efficacy of Lantibiotic Treatment of Staphylococcus aureus-Induced Skin Infections, Monitored by In Vivo Bioluminescent Imaging.

    PubMed

    van Staden, Anton Du Preez; Heunis, Tiaan; Smith, Carine; Deane, Shelly; Dicks, Leon M T

    2016-07-01

    Staphylococcus aureus is a bacterial pathogen responsible for the majority of skin and soft tissue infections. Antibiotics are losing their efficacy as treatment for skin and soft tissue infections as a result of increased resistance in a variety of pathogens, including S. aureus It is thus imperative to explore alternative antimicrobial treatments to ensure future treatment options for skin and soft tissue infections. A select few lantibiotics, a group of natural defense peptides produced by bacteria, inhibit the growth of numerous clinical S. aureus isolates, including methicillin-resistant strains. In this study, the antimicrobial activities of nisin, clausin, and amyloliquecidin, separately administered, were compared to that of a mupirocin-based ointment, which is commonly used as treatment for S. aureus-induced skin infections. Full-thickness excisional wounds, generated on the dorsal surfaces of mice, were infected with a bioluminescent strain of S. aureus (strain Xen 36). The infections were monitored in real time using in vivo bioluminescent imaging. Lantibiotic treatments significantly reduced the bioluminescence of S. aureus Xen 36 to a level similar to that recorded with mupirocin treatment. Wound closure, however, was more pronounced during lantibiotic treatment. Lantibiotics thus have the potential to be used as an alternative treatment option for S. aureus-induced skin infections.

  2. Development of an in vivo animal model for skin penetration in hairless rats assessed by mass balance.

    PubMed

    Simonsen, Lene; Petersen, Mads B; Benfeldt, Eva; Serup, Jørgen

    2002-01-01

    The aim of the study was to develop an in vivo animal model for studies of the penetration of topically applied drugs into the skin of hairless rats. Protective appliances were designed for non-occluded and finite-dose application of topical formulations. The design allowed 2 test sites for each rat and free mobility throughout the test period. By consecutive tape stripping, monitored by measurements of transepidermal water loss and confirmed by histological examination of skin biopsies, 10 tape strippings were found to remove the stratum corneum completely. For assessment of the model, (14)C-salicylic acid and (14)C-butyl salicylate were topically applied. Rapid and differentiated percutaneous absorption of both compounds were shown by urinary excretion data. For (14)C-salicylic acid the amount on the skin surface, in the stratum corneum and in the viable skin was determined. Total mass balance on the applied radioactivity was performed and a recovery of 90 +/- 2% was achieved. The radioactivity found in the protective appliances (<10%) was explained by lateral skin diffusion of the model compounds into the dressings.

  3. Topical glycerol monooleate/propylene glycol formulations enhance 5-aminolevulinic acid in vitro skin delivery and in vivo protophorphyrin IX accumulation in hairless mouse skin.

    PubMed

    Steluti, Regilene; De Rosa, Fernanda Scarmato; Collett, John; Tedesco, Antônio Cláudio; Bentley, Maria Vitória Lopes Badra

    2005-08-01

    Photodynamic therapy (PDT), a potential therapy for cancer treatment, utilizes exogenously applied or endogenously formed photosensitizers, further activated by light in an appropriate wavelength and dose to induce cell death through free radical formation. 5-Aminolevulinic acid (5-ALA) is a pro-drug which can be converted to the effective photosensitizer, protoporphyrin IX (PpIX). However, the use of 5-ALA in PDT is limited by the low penetration capacity of this highly hydrophilic molecule into appropriate skin layers. In the present study, we propose to increase 5-ALA penetration by using formulations containing glycerol monooleate (GMO), an interesting and useful component of pharmaceutical formulations. Propylene glycol solutions containing different concentrations of GMO significantly increased the in vitro skin permeation/retention of 5-ALA in comparison to control solutions. In vivo studies also showed increased PpIX accumulation in mouse hairless skin, after the use of topical 5-ALA formulations containing GMO in a concentration-dependent manner. The results show that skin 5-ALA penetration and PpIX accumulation, important factors for the success of topical 5-ALA-PDT in skin cancer, are optimized by GMO/propylene glycol formulations.

  4. Particle acceleration for delivery deoxyribonucleic acid vaccine into skin in vivo

    NASA Astrophysics Data System (ADS)

    Xinglong, Yu; Xiwen, Zhang; Yuan, Wang; Junshi, Xie; Pengfei, Hao

    2001-08-01

    Skin represents an important immunogenic inductive site, 3%-4% epidermis cells are special antigen-presenting cells. Deoxyribonucleic acid (DNA) vaccine can elicit vigorous immune responses in epidermis cells. The means of delivering DNA vaccine into epidermis cells becomes an important step in DNA vaccine applications. This article presents a new type of gene gun based on the principle of two-stage injector acceleration. DNA coated particles are attached on an screen-type carrier located at the negative pressure inlet, the particles will be sucked into the accelerating channel by negative pressure and be accelerated at a great speed. FLUENT, a computation fluid dynamic application software is used to simulate the flow condition of the injector. Distribution of Mach number, total pressure on exit cross section, and negative pressure on negative pressure inlet are analyzed, by which the process of acceleration of particles is determined. We also measured these parameters in this study. The data show that the particle velocity can be up to 500 m/s and the particles distribute evenly over a circle of Φ 20 mm. The numerical simulation results coincide with experimental data well. Therefore, the results of numerical simulation can be served as guidance for an optimal design of the gene gun and for practical operations. When gene coated particles are distributed evenly, they can penetrate into or even through epidermis cells where the gene can be expressed and subsequently elicits host immune responses. This device may be evaluated in human objects in future.

  5. Broadband absorption and reduced scattering spectra of in-vivo skin can be noninvasively determined using δ-P1 approximation based spectral analysis

    PubMed Central

    Hung, Cheng-Hung; Chou, Ting-Chun; Hsu, Chao-Kai; Tseng, Sheng-Hao

    2015-01-01

    Previously, we revealed that a linear gradient line source illumination (LGLSI) geometry could work with advanced diffusion models to recover the sample optical properties at wavelengths where sample absorption and reduced scattering were comparable. In this study, we employed the LGLSI geometry with a broadband light source and utilized the spectral analysis to determine the broadband absorption and scattering spectra of turbid samples in the wavelength range from 650 to 1350 nm. The performance of the LGLSI δ-P1 diffusion model based spectral analysis was evaluated using liquid phantoms, and it was found that the sample optical properties could be properly recovered even at wavelengths above 1000 nm where μs' to μa ratios were in the range between 1 to 20. Finally, we will demonstrate the use of our system for recovering the 650 to 1350 nm absorption and scattering spectra of in-vivo human skin. We expect this system can be applied to study deep vessel dilation induced hemoglobin concentration variation and determine the water and lipid concentrations of in-vivo skin in clinical settings in the future. PMID:25780735

  6. Optical fiber sensing of human skin emanations

    NASA Astrophysics Data System (ADS)

    Lee, S.-W.; Wang, T.; Selyanchyn, R.; Korposh, S.; James, S. W.

    2015-07-01

    An evanescent-wave optical fibre sensor modified with tetrakis(4-sulfophenyl)porphine (TSPP) and poly(allylamine hydrochloride) (PAH) bilayers using an layer-by-layer (LbL) approach was tested to measure the gas emitted from human skin. Optical intensity changes at different wavelengths in the transmission spectrum of the porphyrin-based film were induced by the human skin gas and measured as sensor response. Influence of relative humidity, which can be a major interference to sensor response, was significantly different when compared to the influence of skin emanations. Responses of the current optical sensor system could be considered as composite sensor array, where different optical wavelengths act as channels that have selective response to specific volatile compounds. Data obtained from the sensor system was analyzed through principal component analysis (PCA). This approach enabled to distinguish skin odors of different people and their altered physiological conditions after alcohol consumption.

  7. In vitro human skin penetration of diethanolamine.

    PubMed

    Kraeling, M E K; Yourick, J J; Bronaugh, R L

    2004-10-01

    Concerns about the safety of diethanolamine (DEA) have been raised by the National Toxicology Program (NTP). Therefore, we measured the extent of DEA absorption in human skin relevant to exposures from shampoos, hair dyes and body lotions. Radiolabeled [14C]-DEA was added to two commercial products from each class and applied to excised viable and non-viable human skin in flow-through diffusion cells. The products remained on the skin for 5, 30 and 24 h for shampoos, hair dyes and body lotions, respectively. After 24 h, most of the absorbed dose was found in skin: 2.8% for shampoos, 2.9% for hair dyes and 10.0% for body lotions. Only small amounts were absorbed into the receptor fluid: 0.08%, 0.09% and 0.9% for shampoos, hair dyes and body lotions respectively. There was no significant difference in the absorption of DEA through viable and non-viable skin or from product application doses of 1, 2 or 3 mg lotion/cm2. In 72 h daily repeat dose studies with a lotion, DEA appeared to accumulate in the skin (29.2%) with little diffusing out into the receptor fluid. Therefore, skin levels of DEA should not be included in estimates of systemic absorption used in exposure assessments.

  8. In vivo visualization of dermal collagen fiber in skin burn by collagen-sensitive second-harmonic-generation microscopy

    NASA Astrophysics Data System (ADS)

    Tanaka, Ryosuke; Fukushima, Shu-ichiro; Sasaki, Kunihiko; Tanaka, Yuji; Murota, Hiroyuki; Matsumoto, Takeshi; Araki, Tsutomu; Yasui, Takeshi

    2013-06-01

    Optical assessment of skin burns is possible with second-harmonic-generation (SHG) microscopy due to its high sensitivity to thermal denaturation of collagen molecules. In contrast to previous studies that were performed using excised tissue specimens ex vivo, in vivo observation of dermal collagen fibers in living rat burn models with SHG microscopy is demonstrated. Changes in signal vanishing patterns in the SHG images are confirmed to be dependent on the burn degree. Comparison of the SHG images with Masson's trichrome-stained images indicated that the observed patterns were caused by the coexistence of molten and fibrous structures of dermal collagen fibers. Furthermore, a quantitative parameter for burn assessment based on the depth profile of the mean SHG intensity across the entire SHG image is proposed. These results and discussions imply a potential of SHG microscopy as a minimally invasive, highly quantitative tool for skin burn assessment.

  9. Propagation of normal human epithelial cell populations using an in vivo culture system. Description and applications.

    PubMed Central

    Klein-Szanto, A. J.; Terzaghi, M.; Mirkin, L. D.; Martin, D.; Shiba, M.

    1982-01-01

    A new model using xenotransplanted human epithelia was developed for the study of toxic and carcinogenic effects of chemicals. Epithelial cells from the respiratory tract of 4 male and 3 female premature and fullterm fetuses were enzymatically removed and inoculated into deepithelialized rat tracheas. These were sealed at both ends and transplanted subcutaneously into nude mice. After 3-4 weeks, a normal mucociliary epithelium covered the tracheal lumen. At this stage the epithelial cells could be isolated again and transplanted into new denuded rat tracheas. This passaging could be repeated up to six times, each permitting an amplification factor of approximately 3. Tracheal transplants containing cells of human origin (in vivo Passages 2-4) were treated with 7,12-dimethylbenz(a)anthracene. Hyperplasias, squamous metaplasias, and dysplasias were seen 1-8 weeks after initiation of treatment, indicating that the responses of human and rodent epithelial cells to polycyclic aromatic hydrocarbons are similar. Initial experiments with skin and esophageal epithelia suggest that other covering epithelia could also be used in this fashion for evaluation of toxicants and carcinogens that are likely to come into contact with these tissues. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:6821529

  10. Birefringence measurements in human skin using polarization-sensitive optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Pierce, Mark C.; Strasswimmer, John; Park, B. H.; Cense, Barry; de Boer, Johannes F.

    2004-07-01

    Optical coherence tomography enables cross-sectional imaging of tissue structure to depths of around 1.5 mm, at high-resolution and in real-time. Incorporation of polarization-sensitivity enables the birefringent properties of tissues to be visualized and quantified. We present polarization-sensitive optical coherence tomography images and quantitative birefringence analysis of in vivo human skin. From measurements on a sample of 5 human volunteers, mean double-pass phase retardation rates of 0.340 +/- 0.143, 0.250 +/- 0.076 and 0.592 +/- 0.142°/μm were obtained for normal skin at the dorsal hand, temple and lower back regions respectively. Compared to these values measured in normal skin, a reduction in birefringence was observed and quantified in human skin following thermal injury. Conversely, increased birefringence was consistently measured at skin sites following wound healing and repair.

  11. Dynamic viscoelastic models of human skin using optical elastography

    PubMed Central

    Kearney, Steven P.; Khan, Altaf; Dai, Zoujun; Royston, Thomas J.

    2015-01-01

    A novel technique for measuring in vivo human skin viscoelastic properties using optical elastography has been developed. The technique uses geometrically focused surface (GFS) waves that allow for wide bandwidth measurements of the wave field. An analytical solution for the case of a radiating annular disk surface source was fit to experimentally measured GFS waves, enabling an estimate of the frequency-dependent surface wavenumber, which can then be related to the dynamic shear modulus. Several viscoelastic models were then fit to the dynamic shear modulus dispersion curve. Viscoelastic models were evaluated based on their overall quality of fit and variability amongst healthy volunteers. An Ecoflex phantom was used to validate the procedure and results by comparison to similar studies using the same type of phantom. For skin results, it was found that the “α” parameters from the fractional models had the least variability, with coefficients of variability of 0.15, and 0.16. The best fitting models were the standard linear solid, and the fractional Voigt, with a mean fit correlation coefficient, R2, of 0.93, 0.89, respectively. This study has demonstrated the efficacy of this new method, and with larger studies the viscoelastic skin models could be used to identify various skin diseases and their response to treatment. PMID:26305137

  12. Modeling and analysis of cosmetic treatment effects on human skin

    NASA Astrophysics Data System (ADS)

    Lunderstaedt, Reinhart A.; Hopermann, Hermann; Hillemann, Thomas

    2000-10-01

    In view of treatment effects of cosmetics, quality management becomes more and more important. Due to the efficiency reasons it is desirable to quantify these effects and predict them as a function of time. For this, a mathematical model of the skin's surface (epidermis) is needed. Such a model cannot be worked out purely analytically. It can only be derived with the help of measurement data. The signals of interest as output of different measurement devices consist of two parts: noise of high (spatial) frequencies (stochastic signal) and periodic functions (deterministic signal) of low (spatial) frequencies. Both parts can be separated by correlation analysis. The paper introduces in addition to the Fourier Transform (FT) with the Wavelet Transform (WT), a brand new, highly sophisticated method with excellent properties for both modeling the skin's surface as well as evaluating treatment effects. Its main physical advantage is (in comparison to the FT) that local irregularities in the measurement signal (e.g. by scars) remain at their place and are not represented as mean square values as it is the case when applying the FT. The method has just now been installed in industry and will there be used in connection with a new in vivo measurement device for quality control of cosmetic products. As texture parameter for an integral description of the human skin the fractal dimension D is used which is appropriate for classification of different skin regions and treatment effects as well.

  13. New methodology for mechanical characterization of human superficial facial tissue anisotropic behaviour in vivo.

    PubMed

    Then, C; Stassen, B; Depta, K; Silber, G

    2017-02-21

    Mechanical characterization of human superficial facial tissue has important applications in biomedical science, computer assisted forensics, graphics, and consumer goods development. Specifically, the latter may include facial hair removal devices. Predictive accuracy of numerical models and their ability to elucidate biomechanically relevant questions depends on the acquisition of experimental data and mechanical tissue behavior representation. Anisotropic viscoelastic behavioral characterization of human facial tissue, deformed in vivo with finite strain, however, is sparse. Employing an experimental-numerical approach, a procedure is presented to evaluate multidirectional tensile properties of superficial tissue layers of the face in vivo. Specifically, in addition to stress relaxation, displacement-controlled multi-step ramp-and-hold protocols were performed to separate elastic from inelastic properties. For numerical representation, an anisotropic hyperelastic material model in conjunction with a time domain linear viscoelasticity formulation with Prony series was employed. Model parameters were inversely derived, employing finite element models, using multi-criteria optimization. The methodology provides insight into mechanical superficial facial tissue properties. Experimental data shows pronounced anisotropy, especially with large strain. The stress relaxation rate does not depend on the loading direction, but is strain-dependent. Preconditioning eliminates equilibrium hysteresis effects and leads to stress-strain repeatability. In the preconditioned state tissue stiffness and hysteresis insensitivity to strain rate in the applied range is evident. The employed material model fits the nonlinear anisotropic elastic results and the viscoelasticity model reasonably reproduces time-dependent results. Inversely deduced maximum anisotropic long-term shear modulus of linear elasticity is G∞,max(aniso)=2.43kPa and instantaneous initial shear modulus at an

  14. Photoacoustic spectroscopy to evaluate the potentiality of bee-propolis as UV protector: In vivo test in humans

    NASA Astrophysics Data System (ADS)

    Sehn, E.; Silva, K. C.; Bento, A. C.; Baesso, M. L.; Franco, S. L.

    2005-06-01

    In this work, the Photoacoustic Spectroscopy was employed to evaluate the potentiality of bee-propolis as UV protector. The experiments were performed to obtain the creams optical absorption spectra in the UV spectral region and also to evaluate in vivo the penetration rate of the obtained product in humans. The results showed the spectral response of the developed bee-propolis creams, and also revealed that two hours after the application about 40 % of the cream signal was still detected on the skin surface.

  15. Direct observation of liposome uptake by leukocytes in vivo in skin blood vessels using intravital fluorescence microscopy

    NASA Astrophysics Data System (ADS)

    Devoisselle, Jean-Marie; Mordon, Serge R.; Begu, Sylvie; Desmettre, Thomas

    2000-04-01

    This study aimed to observe liposome uptake by leukocytes in vivo. The study was performed on skin by using a dorsal skin-fold chamber implanted in golden hamsters using intravital microscopy. 5,6-CF-encapsulated PEGylated liposomes were injected intravenously. The skin microcirculation was observed with an intravital Eclipse E800 Nikon microscope fitted with a Xenon light source and an epi-fluorescence assembly. An ultra-high sensitivity video-camera mounted on the microscope projected the image onto a monitor, and the images were recorded for playback analysis with a digital video cassette recorder. An acute inflammatory response was obtained by removing one complete layer of skin and the underlying fascia and avascular tissue on the opposing side of the flap corresponding to an area equivalent to the window aperture. Using these model and set-up, leukocyte rolling and adhesion were easily observed and the entry of PEGylated liposomes into hamster blood leukocytes was studied for a period of 6 hours. PEGylated liposomes were clearly identified alone inside the blood flow and inside the leukocytes as soon as the inflammatory reaction appeared. This study shows for the first time that blood leukocytes in their natural milieu of whole blood are capable of interacting with, and taking up liposomes. This observation is in accordance with previous in vitro studies.

  16. In vivo acceleration of skin growth using a servo-controlled stretching device.

    PubMed

    Chin, Michael S; Ogawa, Rei; Lancerotto, Luca; Pietramaggiori, Giorgio; Schomacker, Kevin T; Mathews, Jasmine C; Scherer, Saja S; Van Duyn, Paul; Prsa, Michael J; Ottensmeyer, Mark P; Veves, Aristidis; Orgill, Dennis P

    2010-06-01

    Tension is a principal force experienced by skin and serves a critical role in growth and development. Optimal tension application regimens may be an important component for skin tissue engineering and dermatogenesis. In this study, we designed and tested a novel servo-controlled skin-stretching device to apply predetermined tension and waveforms in mice. The effects of static and cyclical stretching forces were compared in 48 mice by measuring epidermal proliferation, angiogenesis, cutaneous perfusion, and principal growth factors using immunohistochemistry, real-time reverse transcriptase-polymerase chain reaction, and hyperspectral imaging. All stretched samples had upregulated epidermal proliferation and angiogenesis. Real-time reverse transcriptase-polymerase chain reaction of epidermal growth factor, transforming growth factor beta1, and nerve growth factor demonstrated greater expression in cyclically stretched skin when compared to static stretch. Hypoxia-induced factor 1alpha was significantly upregulated in cyclically stretched skin, but poststretch analysis demonstrated well-oxygenated tissue, collectively suggesting the presence of transient hypoxia. Waveform-specific mechanical loads may accelerate tissue growth by mechanotransduction and as a result of repeated cycles of temporary hypoxia. Further analysis of mechanotransduction signaling pathways may provide additional insight to improve skin tissue engineering methods and optimize our device.

  17. Windowless ultrasound photoacoustic cell for in vivo mid-IR spectroscopy of human epidermis: low interference by changes of air pressure, temperature, and humidity caused by skin contact opens the possibility for a non-invasive monitoring of glucose in the interstitial fluid.

    PubMed

    Pleitez, Miguel A; Lieblein, Tobias; Bauer, Alexander; Hertzberg, Otto; von Lilienfeld-Toal, Hermann; Mäntele, Werner

    2013-08-01

    The application of a novel open, windowless cell for the photoacoustic infrared spectroscopy of human skin is described. This windowless cavity is tuned for optimum performance in the ultrasound range between 50 and 60 kHz. In combination with an external cavity tunable quantum cascade laser emitting in the range from ~1000 cm(-1) to 1245 cm(-1), this approach leads to high signal-to-noise-ratio (SNR) for mid-infrared spectra of human skin. This opens the possibility to measure in situ the absorption spectrum of human epidermis in the mid-infrared region at high SNR in a few (~5) seconds. Rapid measurement of skin spectra greatly reduces artifacts arising from movements. As compared to closed resonance cells, the windowless cell exhibits the advantage that the influence of air pressure variations, temperature changes, and air humidity buildup that are caused by the contact of the cell to the skin surface can be minimized. We demonstrate here that this approach can be used for continuous and non-invasive monitoring of the glucose level in human epidermis, and thus may form the basis for a non-invasive monitoring of the glucose level for diabetes patients.

  18. Windowless ultrasound photoacoustic cell for in vivo mid-IR spectroscopy of human epidermis: Low interference by changes of air pressure, temperature, and humidity caused by skin contact opens the possibility for a non-invasive monitoring of glucose in the interstitial fluid

    NASA Astrophysics Data System (ADS)

    Pleitez, Miguel A.; Lieblein, Tobias; Bauer, Alexander; Hertzberg, Otto; von Lilienfeld-Toal, Hermann; Mäntele, Werner

    2013-08-01

    The application of a novel open, windowless cell for the photoacoustic infrared spectroscopy of human skin is described. This windowless cavity is tuned for optimum performance in the ultrasound range between 50 and 60 kHz. In combination with an external cavity tunable quantum cascade laser emitting in the range from ˜1000 cm-1 to 1245 cm-1, this approach leads to high signal-to-noise-ratio (SNR) for mid-infrared spectra of human skin. This opens the possibility to measure in situ the absorption spectrum of human epidermis in the mid-infrared region at high SNR in a few (˜5) seconds. Rapid measurement of skin spectra greatly reduces artifacts arising from movements. As compared to closed resonance cells, the windowless cell exhibits the advantage that the influence of air pressure variations, temperature changes, and air humidity buildup that are caused by the contact of the cell to the skin surface can be minimized. We demonstrate here that this approach can be used for continuous and non-invasive monitoring of the glucose level in human epidermis, and thus may form the basis for a non-invasive monitoring of the glucose level for diabetes patients.

  19. Electrical conductivity imaging of lower extremities using MREIT: postmortem swine and in vivo human experiments.

    PubMed

    Woo, Eung Je; Kim, Hyung Joong; Minhas, Atul S; Kim, Young Tae; Jeong, Woo Chul; Kwon, O

    2008-01-01

    Cross-sectional conductivity images of lower extremities were reconstructed using Magnetic Resonance Electrical Impedance Tomography (MREIT) techniques. Carbon-hydrogel electrodes were adopted for postmortem swine and in vivo human imaging experiments. Due to their large surface areas and good contacts on the skin, we could inject as much as 10 mA into the lower extremities of human subjects without producing a painful sensation. Using a 3T MREIT system, we first performed a series of postmortem swine experiments and produced high-resolution conductivity images of swine legs. Validating the experimental protocol for the lower extremities, we revised it for the following human experiments. After the review of the Institutional Review Board (IRB), we conducted our first MREIT experiments of human subjects using the same 3T MREIT system. Collecting magnetic flux density data inside lower extremities subject to multiple injection currents, we reconstructed cross-sectional conductivity images using the harmonic B(z) algorithm. The conductivity images very well distinguished different parts of muscles inside the lower extremities. The outermost fatty layer was clearly shown in each conductivity image. We could observe severe noise in the outer layer of the bones primarily due to the MR signal void phenomenon there. Reconstructed conductivity images indicated that the internal regions of the bones have relatively high conductivity values. Future study is desired in terms of the conductivity image reconstruction algorithm to improve the image quality. Further human imaging experiments are planned and being conducted to produce high-resolution conductivity images from different parts of the human body.

  20. Bilayer hydrogel with autologous stem cells derived from debrided human burn skin for improved skin regeneration.

    PubMed

    Natesan, Shanmugasundaram; Zamora, David O; Wrice, Nicole L; Baer, David G; Christy, Robert J

    2013-01-01

    The objective of this study was to demonstrate that stem cells isolated from discarded skin obtained after debridement can be used with collagen and fibrin-based scaffolds to develop a tissue-engineered vascularized dermal equivalent. Discarded tissue samples were collected from severely burned patients undergoing wound debridement. Stem cells were isolated from the adipose tissue layer and their growth and immunophenotype characterized. To develop a skin equivalent, debrided skin adipose stem cells (dsASCs) were added to a collagen-polyethylene glycol (PEG) fibrin-based bilayer hydrogel and analyzed in vitro. The effect of the bilayered hydrogels on wound healing was demonstrated using an excision wound model in athymic rats. The dsASCs isolated from all samples were CD90, CD105, and stromal cell surface protein-1 positive, similar to adipose stem cells isolated from normal human lipoaspirates. Within the bilayer hydrogels, dsASCs proliferated and differentiated, maintained a spindle-shaped morphology in collagen, and developed a tubular microvascular network in the PEGylated fibrin. Rat excision wounds treated with bilayer hydrogels showed less wound contraction and exhibited better dermal matrix deposition and epithelial margin progression than controls. Stem cells can be isolated from the adipose layer of burned skin obtained during debridement. When dsASCs are incorporated within collagen-PEGylated fibrin bilayer hydrogels, they develop stromal and vascular phenotypes through matrix-directed differentiation without use of growth factors. Preliminary in vivo studies indicate that dsASC-bilayer hydrogels contribute significantly to wound healing and provide support for their use as a vascularized dermal substitute for skin regeneration to treat large surface area burns.

  1. Collagen Fragmentation Promotes Oxidative Stress and Elevates Matrix Metalloproteinase-1 in Fibroblasts in Aged Human Skin

    PubMed Central

    Fisher, Gary J.; Quan, Taihao; Purohit, Trupta; Shao, Yuan; Cho, Moon Kyun; He, Tianyuan; Varani, James; Kang, Sewon; Voorhees, John J.

    2009-01-01

    Aged human skin is fragile because of fragmentation and loss of type I collagen fibrils, which confer strength and resiliency. We report here that dermal fibroblasts express increased levels of collagen-degrading matrix metalloproteinases-1 (MMP-1) in aged (>80 years old) compared with young (21 to 30 years old) human skin in vivo. Transcription factor AP-1 and α2β1 integrin, which are key regulators of MMP-1 expression, are also elevated in fibroblasts in aged human skin in vivo. MMP-1 treatment of young skin in organ culture causes fragmentation of collagen fibrils and reduces fibroblast stretch, consistent with reduced mechanical tension, as observed in aged human skin. Limited fragmentation of three-dimensional collagen lattices with exogenous MMP-1 also reduces fibroblast stretch and mechanical tension. Furthermore, fibroblasts cultured in fragmented collagen lattices express elevated levels of MMP-1, AP-1, and α2β1 integrin. Importantly, culture in fragmented collagen raises intracellular oxidant levels and treatment with antioxidant MitoQ10 significantly reduces MMP-1 expression. These data identify positive feedback regulation that couples age-dependent MMP-1-catalyzed collagen fragmentation and oxidative stress. We propose that this self perpetuating cycle promotes human skin aging. These data extend the current understanding of the oxidative theory of aging beyond a cellular-centric view to include extracellular matrix and the critical role that connective tissue microenvironment plays in the biology of aging. PMID:19116368

  2. Investigation of In Vivo skin stiffness anisotropy in breast cancer related lymphoedema.

    PubMed

    Coutts, L V; Miller, N R; Mortimer, P S; Bamber, J C

    2016-01-04

    There is a limited range of suitable measurement techniques for detecting and assessing breast cancer related lymphoedema (BCRL). This study investigated the suitability of using skin stiffness measurements, with a particular focus on the variation in stiffness with measurement direction (known as anisotropy). In addition to comparing affected tissue with the unaffected tissue on the corresponding site on the opposite limb, volunteers without BCRL were tested to establish the normal variability in stiffness anisotropy between these two corresponding regions of skin on each opposite limb. Multi-directional stiffness was measured with an Extensometer, within the higher stiffness region that skin typically displays at high applied strains, using a previously established protocol developed by the authors. Healthy volunteers showed no significant difference in anisotropy between regions of skin on opposite limbs (mean decrease of 4.7 +/-2.5% between non-dominant and dominant arms), whereas BCRL sufferers showed a significant difference between limbs (mean decrease of 51.0+/-16.3% between unaffected and affected arms). A large difference in anisotropy was apparent even for those with recent onset of the condition, indicating that the technique may have potential to be useful for early detection. This difference also appeared to increase with duration since onset. Therefore, measurement of stiffness anisotropy has potential value for the clinical assessment and diagnosis of skin conditions such as BCRL. The promising results justify a larger study with a larger number of participants.

  3. In vivo traffic of indium-111-oxine labeled human lymphocytes collected by automated apheresis

    SciTech Connect

    Read, E.J.; Keenan, A.M.; Carter, C.S.; Yolles, P.S.; Davey, R.J. )

    1990-06-01

    The in vivo traffic patterns of autologous lymphocytes were studied in five normal human volunteers using lymphocytes obtained by automated apheresis, separated on Ficoll-Hypaque gradients, and labeled ex vivo with {sup 111}In-oxine. Final lymphocyte infusions contained 1.8-3.1 X 10(9) cells and 270-390 microCi (9.99-14.43 MBq) {sup 111}In, or 11-17 microCi (0.41-0.63 MBq) per 10(8) lymphocytes. Gamma imaging showed transient lung uptake and significant retention of radioactivity in the liver and spleen. Progressive uptake of activity in normal, nonpalpable axillary and inguinal lymph nodes was seen from 24 to 96 hr. Accumulation of radioactivity also was demonstrated at the forearm skin test site, as well as in its associated epitrochlear and axillary lymph nodes, in a subject who had been tested for delayed hypersensitivity with tetanus toxoid. Indium-111-oxine labeled human lymphocytes may provide a useful tool for future studies of normal and abnormal lymphocyte traffic.

  4. In vivo percutaneous absorption of boron as boric acid, borax, and disodium octaborate tetrahydrate in humans: a summary.

    PubMed

    Wester, R C; Hui, X; Maibach, H I; Bell, K; Schell, M J; Northington, D J; Strong, P; Culver, B D

    1998-01-01

    Literature from the first half of this century reports concern for toxicity from topical use of boric acid, but assessment of percutaneous absorption has been impaired by lack of analytical sensitivity. Analytical methods in this study included inductively coupled plasma-mass spectrometry, which now allows quantitation of percutaneous absorption of 10B in 10B-enriched boric acid, borax, and disodium octaborate tetrahydrate (DOT) in biological matrices. This made it possible, in the presence of comparatively large natural dietary boron intakes for the in vivo segment of this study, to quantify the boron passing through skin. Human volunteers were dosed with 10B-enriched boric acid, 5.0%, borax, 5.0%, or disodium octaborate tetrahydrate, 10% in aqueous solutions. Urinalysis, for boron and changes in boron isotope ratios, was used to measure absorption. Boric acid in vivo percutaneous absorption was 0.226 (SD = 0.125) mean percent dose, with flux and permeability constant (Kp) calculated at 0.009 microg/cm2/h and 1.9 x 10(-7) cm/h, respectively. Borax absorption was 0.210 (SD = 0.194) mean percent dose, with flux and Kp calculated at 0.009 microg/cm2/h and 1.8 x 10(-7) cm/h, respectively. DOT absorption was 0.122 (SD = 0.108) mean percent, with flux and Kp calculated at 0.01 microg/cm2/h and 1.0 x 10(-7) cm/h, respectively. Pretreatment with the potential skin irritant 2% sodium lauryl sulfate had no effect on boron skin absorption. These in vivo results show that percutaneous absorption of boron, as boric acid, borax, and disodium octaborate tetrahydrate, through intact human skin is low and is significantly less than the average daily dietary intake. This very low boron skin absorption makes it apparent that, for the borates tested, the use of gloves to prevent systemic uptake is unnecessary. These findings do not apply to abraded or otherwise damaged skin.

  5. Investigation of in vivo potential of scorpion venom against skin tumorigenesis in mice via targeting markers associated with cancer development

    PubMed Central

    Al Asmari, Abdulrahman K; Khan, Abdul Quaiyoom

    2016-01-01

    Cancer is the leading cause of morbidity and mortality all over the world in spite of the advances made in its management. In this study, we investigated the in vivo anti-tumorigenic potential of the venom obtained from a medically important scorpion species Leiurus quinquestriatus on chemically induced skin cancer in mice. Animals were divided into five groups, with 13 animals in each group. All the treatments were given topically on the shaved dorsal surface of the skin. Animals in Group 1 received vehicle only (0.2 mL acetone). Moreover, 7,12-dimethylbenz[a]anthracene (DMBA, 400 nmol per mouse) was applied to all the animals in the remaining four groups. After 1 week, different concentrations of venom (17.5 μg, 35 μg, and 52.5 μg per animal) were applied to each animal in the Groups III–V. Thirty minutes after the application of venom, croton oil was applied on the same position where venom was administered to the animals of Groups III–V. Animals in Group II were treated as the positive control (without venom) and received croton oil as in Groups III–V. The findings of this study revealed that venom extract of L. quinquestriatus inhibits DMBA + croton oil-induced mouse skin tumor incidence and tumor multiplicity. Venom treatment also decreased the expression of proinflammatory cytokines. Immunohistochemistry results showed a downregulation of the expression of molecular markers such as Ki-67, nuclear factor kappa-B, cyclooxygenase-2, B-cell lymphoma-2, and vascular endothelial growth factor, in venom-treated animals. Our findings suggest that the venom of L. quinquestriatus possesses in vivo anticancer potential and may be used in the development of anticancer molecules. PMID:27799739

  6. Diffuse Reflectance Spectroscopy of Human Skin Using a Commercial Fiber Optic Spectrometer

    SciTech Connect

    Atencio, J. A. Delgado; Rodriguez, M. Cunill; Montiel, S. Vazquez y; Castro, Jorge; Rodriguez, A. Cornejo; Gutierrez, J. L.; Martinez, F.; Gutierrez, B.; Orozco, E.

    2008-08-11

    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.

  7. Microindentation for In Vivo Measurement of Bone Tissue Mechanical Properties in Humans

    PubMed Central

    Diez-Perez, Adolfo; Güerri, Roberto; Nogues, Xavier; Cáceres, Enric; Peña, Maria Jesus; Mellibovsky, Leonardo; Randall, Connor; Bridges, Daniel; Weaver, James C; Proctor, Alexander; Brimer, Davis; Koester, Kurt J; Ritchie, Robert O; Hansma, Paul K

    2010-01-01

    Bone tissue mechanical properties are deemed a key component of bone strength, but their assessment requires invasive procedures. Here we validate a new instrument, a reference point indentation (RPI) instrument, for measuring these tissue properties in vivo. The RPI instrument performs bone microindentation testing (BMT) by inserting a probe assembly through the skin covering the tibia and, after displacing periosteum, applying 20 indentation cycles at 2 Hz each with a maximum force of 11 N. We assessed 27 women with osteoporosis-related fractures and 8 controls of comparable ages. Measured total indentation distance (46.0 ± 14 versus 31.7 ± 3.3 µm, p = .008) and indentation distance increase (18.1 ± 5.6 versus 12.3 ± 2.9 µm, p = .008) were significantly greater in fracture patients than in controls. Areas under the receiver operating characteristic (ROC) curve for the two measurements were 93.1% (95% confidence interval [CI] 83.1–100) and 90.3% (95% CI 73.2–100), respectively. Interobserver coefficient of variation ranged from 8.7% to 15.5%, and the procedure was well tolerated. In a separate study of cadaveric human bone samples (n = 5), crack growth toughness and indentation distance increase correlated (r = –0.9036, p = .018), and scanning electron microscope images of cracks induced by indentation and by experimental fractures were similar. We conclude that BMT, by inducing microscopic fractures, directly measures bone mechanical properties at the tissue level. The technique is feasible for use in clinics with good reproducibility. It discriminates precisely between patients with and without fragility fracture and may provide clinicians and researchers with a direct in vivo measurement of bone tissue resistance to fracture. © 2010 American Society for Bone and Mineral Research. PMID:20200991

  8. Imaging calcium carbonate distribution in human sweat pore in vivo using nonlinear microscopy

    NASA Astrophysics Data System (ADS)

    Chen, Xueqin; Gasecka, Alicja; Formanek, Florian; Galey, Jean-Baptiste; Rigneault, Hervé

    2015-03-01

    Nonlinear microscopies, including two-photon excited autofluorescence (TPEF) and coherent anti-Stokes Raman scattering (CARS), were used to study individual human sweat pore morphology and topically applied antiperspirant salt penetration inside sweat pore, in vivo on human palms. Sweat pore inner morphology in vivo was imaged up to the depth of 100 μm by TPEF microscopy. The 3D penetration and distribution of "in situ calcium carbonate" (isCC), an antiperspirant salt model, was investigated using CARS microscopy.

  9. Experiments on Analysing Voice Production: Excised (Human, Animal) and In Vivo (Animal) Approaches.

    PubMed

    Döllinger, Michael; Kobler, James; Berry, David A; Mehta, Daryush D; Luegmair, Georg; Bohr, Christopher

    Experiments on human and on animal excised specimens as well as in vivo animal preparations are so far the most realistic approaches to simulate the in vivo process of human phonation. These experiments do not have the disadvantage of limited space within the neck and enable studies of the actual organ necessary for phonation, i.e., the larynx. The studies additionally allow the analysis of flow, vocal fold dynamics, and resulting acoustics in relation to well-defined laryngeal alterations.

  10. In vivo and in vitro analysis of low level light therapy: a useful therapeutic approach for sensitive skin.

    PubMed

    Choi, M; Kim, J E; Cho, K H; Lee, J H

    2013-11-01

    Sensitive skin is a relatively common dermatologic condition and no optimal treatments have been established so far. Low-level laser/light therapy (LLLT) has been used for its biostimulative effect in various clinical settings. The purpose of this study was to investigate whether low-level laser/light therapy can improve sensitive skin clinically and to evaluate the effects of LLLT on skin in vitro. Twenty-eight patients complaining of sensitive skin were treated with low-level polarized light, and clinical results were evaluated using subjective and objective method. To investigate possible working mechanism of LLLT on skin, cultured human keratinocytes pretreated with nontoxic concentration of sodium lauryl sulfate (SLS) were used. Cytokines released from irritated keratinocytes after LLLT were analyzed. All patients showed subjective and objective improvement after treatment. No adverse effects were reported. The average number of LLLT sessions required to achieve clinical improvement was 9.9, and cumulative dose of LLLT was 71.3 J/cm(2) on the average. Erythema index decreased significantly after LLLT treatment (p = 0.017). In vitro assay showed that LLLT significantly reduced the release of VEGF from SLS-pretreated keratinocytes (p = 0.021). Our results suggest that LLLT could be a useful and safe treatment modality for sensitive skin, and modification of inflammatory cytokines released from irritated keratinocytes may be considered as one of plausible mechanisms in sensitive skin treated with LLLT.

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

    PubMed

    Shu, Muya; Wang, Yanhan; Yu, Jinghua; Kuo, Sherwin; Coda, Alvin; Jiang, Yong; Gallo, Richard L; Huang, Chun-Ming

    2013-01-01

    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.

  12. Fluorescence excitation-emission matrix spectroscopy of vitiligo skin in vivo (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Zhao, Jianhua; Richer, Vincent; Al Jasser, Mohammed; Zandi, Soodabeh; Kollias, Nikiforos; Kalia, Sunil; Zeng, Haishan; Lui, Harvey

    2016-02-01

    Fluorescence signals depend on the intensity of the exciting light, the absorption properties of the constituent molecules, and the efficiency with which the absorbed photons are converted to fluorescence emission. The optical features and appearance of vitiligo have been explained primarily on the basis of reduced epidermal pigmentation, which results in abnormal white patches on the skin. The objective of this study is to explore the fluorescence properties of vitiligo and its adjacent normal skin using fluorescence excitation-emission matrix (EEM) spectroscopy. Thirty five (35) volunteers with vitiligo were acquired using a double-grating spectrofluorometer with excitation and emission wavelengths of 260-450 nm and 300-700 nm respectively. As expected, the most pronounced difference between the spectra obtained from vitiligo lesions compared to normally pigmented skin was that the overall fluorescence was much higher in vitiligo; these differences increased at shorter wavelengths, thus matching the characteristic spectral absorption of epidermal melanin. When comparing the fluorescence spectra from vitiligo to normal skin we detected three distinct spectral bands centered at 280nm, 310nm, and 335nm. The 280nm band may possibly be related to inflammation, whereas the 335 nm band may arise from collagen or keratin cross links. The source of the 310 nm band is uncertain; it is interesting to note its proximity to the 311 nm UV lamps used for vitiligo phototherapy. These differences are accounted for not only by changes in epidermal pigment content, but also by other optically active cutaneous biomolecules.

  13. In vivo determination of the diclofenac skin reservoir: comparison between passive, occlusive, and iontophoretic application

    PubMed Central

    Clijsen, Ron; Baeyens, Jean Pierre; Barel, André Odilon; Clarys, Peter

    2015-01-01

    Aim There is scarce information concerning the pharmacodynamic behavior of topical substances used in the physiotherapy setting. The aim of the present study was to estimate the formation and emptying of the diclofenac (DF) skin reservoir after passive, semiocclusive, and electrically assisted applications of DF. Subjects and methods Five different groups of healthy volunteers (ntotal=60, 23 male and 37 female), participated in this study. A 1% DF (Voltaren Emulgel) formulation (12 mg) was applied on the volar forearms on randomized defined circular skin areas of 7 cm2. DF was applied for 20 minutes under three different conditions at the same time. The presence of DF in the skin results in a reduction of the methyl nicotinate (MN) response. To estimate the bioavailability of DF in the skin, MN responses at different times following initial DF application (1.5, 6, 24, 32, 48, 72, 96, and 120 hours) were analyzed. Results At 1.5 hours after the initial DF application, a significant decrease in MN response was detected for the occluded and iontophoretic delivery. Passive application resulted in a decrease of the MN response from 6 hours post-DF application. The inhibition remained up to 32 hours post-DF application for the iontophoretic delivery, 48 hours for the occluded application, and 72 hours for the passive delivery. At 96 and 120 hours post-DF application none of the MN responses was inhibited. Conclusion The formation and emptying of a DF skin reservoir was found to be dependent on the DF-application mode. Penetration-enhanced delivery resulted in a faster emptying of the reservoir. PMID:25709408

  14. Opto-thermal measurements for the non-invasive, non-occlusive monitoring of in vivo skin condition.

    PubMed

    Bindra, R M; Imhof, R E; Andrew, J J; Cummins, P G; Eccleston, G M

    1995-06-01

    Summary Opto-thermal transient radiometry (OTTER) is a non-invasive measurement technique, well suited for in vivo skin research. Its excitation and detection wavelengths can be selected to give a high sensitivity to stratum corneum hydration. This is demonstrated with measurements of hydration changes resulting from occlusion with a neoprene cover and with a topical application of an occlusive preparation. In the former case, the hydration was found to recover to normal levels upon exposure to atmospheric conditions in a characteristic time of 15 min. In the latter case, a topical application of petroleum jelly was found to lead to a doubling of stratum corneum hydration over 2h. This ability to measure hydration changes in the presence of topical hydrating agents is thought to be a particularly valuable property of the OTTER technique. With a different choice of excitation and detection wavelengths, OTTER can be used to measure skin thickness, from the surface down to the vascular bed. This technique was used to measure a skin thickness map of the ventral surface of the forearm of a volunteer, showing distinct thickening near the wrist and ulna. Another use of this technique is the study of changes in subcutaneous blood distribution associated with erythema. As a demonstration of this, blood distribution changes brought about by the topical application of a salicylate/nicotinate preparation were studied. The main finding is that the subcutaneous blood spreads towards the surface, with the mean depth decreasing from 63 mum to 55mum.

  15. 2016 Arte Poster Competition First Place Winner: Circadian Rhythm and UV-Induced Skin Damage: An In Vivo Study.

    PubMed

    Guan, Linna; Suggs, Amanda; Ahsanuddin, Sayeeda; Tarrillion, Madeline; Selph, Jacqueline; Lam, Minh; Baron, Elma

    2016-09-01

    Exposure of the skin to ultraviolet (UV) irradiation causes many detrimental effects through mechanisms related to oxidative stress and DNA damage. Excessive oxidative stress can cause apoptosis and cellular dysfunction of epidermal cells leading to cellular senescence and connective tissue degradation. Direct and indirect damage to DNA predisposes the skin to cancer formation. Chronic UV exposure also leads to skin aging manifested as wrinkling, loss of skin tone, and decreased resilience. Fortunately, human skin has several natural mechanisms for combating UV-induced damage. The mechanisms operate on a diurnal rhythm, a cycle that repeats approximately every 24 hours. It is known that the circadian rhythm is involved in many skin physiologic processes, including water regulation and epidermal stem cell function. This study evaluated whether UV damage and the skin's natural mechanisms of inflammation and repair are also affected by circadian rhythm. We looked at UV-induced erythema on seven human subjects irradiated with simulated solar radiation in the morning (at 08:00 h) versus in the afternoon (at 16:00 h). Our data suggest that the same dose of UV radiation induces significantly more inflammation in the morning than in the afternoon. Changes in protein expression relevant to DNA damage, such as xeroderma pigmentosum, complementation group A (XPA), and cyclobutane pyrimidine dimers (CPD) from skin biopsies correlated with our clinical results. Both XPA and CPD levels were higher after the morning UV exposure compared with the afternoon exposure.

    J Drugs Dermatol. 2016;15(9):1124-1130.

  16. Absorption of lawsone through human skin.

    PubMed

    Kraeling, Margaret E K; Bronaugh, Robert L; Jung, Connie T

    2007-01-01

    Lawsone (2-hydroxy-1,4-naphthoquinone) is the principal color ingredient in henna, a color additive approved with limitations for coloring hair by the Food and Drug Administration (FDA) under 21 CFR 73.2190. In 2002, the scientific committee on cosmetics and non-food products (SCCNFP), now known as the scientific committee for consumer products (SCCP), evaluated the safety of lawsone as a coloring agent in hair dye products of the European Union (EU). The SCCNFP concluded that lawsone was mutagenic and not suitable for use as a hair coloring agent. As a result, studies were conducted to measure the extent of lawsone absorption through human skin. Lawsone skin absorption was determined from two hair coloring products and two shampoo products, all containing henna. [(14)C]-Lawsone (sp. act. 22.9 mCi/mmol) was added to each commercial product and the products were applied to dermatomed, nonviable human skin mounted in flow-through diffusion cells perfused with a physiological buffer (HEPES-buffered Hanks' balanced salt solution, pH 7.4). Products remained on the skin for 5 minutes (shampoos) and 1 hour (hair color paste). For the henna hair paste products, 0.3 and 1.3% of the applied dose was absorbed into the receptor fluid in 24 hours while 2.2 and 4.0% remained in the skin. For both henna shampoo products, 0.3% of the applied dose was absorbed into the receptor fluid at 24 hours while 3.6 and 6.8% remained in the skin. For all products, most of the lawsone applied was washed from the surface of the skin (83-102%) at the end of the exposure period. Extended absorption studies were conducted for 72 hours to determine if skin levels of lawsone in the 24 hour studies might eventually be percutaneously absorbed. These studies determined that the majority of the lawsone remained in the skin with only a small but significant increase (for three out of four products) in receptor fluid values. Therefore, it appears that receptor fluid values would give a good estimate of

  17. Epigenetic and in vivo comparison of diverse MSC sources reveals an endochondral signature for human hematopoietic niche formation

    PubMed Central

    Etchart, Nathalie; Thomas, Daniel; Hofmann, Nicole A.; Fruehwirth, Margareta; Sinha, Subarna; Chan, Charles K.; Senarath-Yapa, Kshemendra; Seo, Eun-Young; Wearda, Taylor; Hartwig, Udo F.; Beham-Schmid, Christine; Trajanoski, Slave; Lin, Qiong; Wagner, Wolfgang; Dullin, Christian; Alves, Frauke; Andreeff, Michael; Weissman, Irving L.; Longaker, Michael T.; Schallmoser, Katharina; Majeti, Ravindra; Strunk, Dirk

    2015-01-01

    In the last decade there has been a rapid expansion in clinical trials using mesenchymal stromal cells (MSCs) from a variety of tissues. However, despite similarities in morphology, immunophenotype, and differentiation behavior in vitro, MSCs sourced from distinct tissues do not necessarily have equivalent biological properties. We performed a genome-wide methylation, transcription, and in vivo evaluation of MSCs from human bone marrow (BM), white adipose tissue, umbilical cord, and skin cultured in humanized media. Surprisingly, only BM-derived MSCs spontaneously formed a BM cavity through a vascularized cartilage intermediate in vivo that was progressively replaced by hematopoietic tissue and bone. Only BM-derived MSCs exhibited a chondrogenic transcriptional program with hypomethylation and increased expression of RUNX3, RUNX2, BGLAP, MMP13, and ITGA10 consistent with a latent and primed skeletal developmental potential. The humanized MSC–derived microenvironment permitted homing and maintenance of long-term murine SLAM+ hematopoietic stem cells (HSCs), as well as human CD34+/CD38−/CD90+/CD45RA+ HSCs after cord blood transplantation. These studies underscore the profound differences in developmental potential between MSC sources independent of donor age, with implications for their clinical use. We also demonstrate a tractable human niche model for studying homing and engraftment of human hematopoietic cells in normal and neoplastic states. PMID:25406351

  18. IN VIVO EVALUATION OF SKIN IRRITATION POTENTIAL, MELASMA AND SEBUM CONTENT FOLLOWING LONG TERM APPLICATION OF SKIN CARE CREAM IN HEALTHY ADULTS, USING NON-INVASIVE BIOMETROLOGICAL TECHNIQUES.

    PubMed

    Arshad, Atif I; Khan, Shoaib H M; Akhtar, Naveed; Mahmood, Asif; Sarfraz, Rai Muhammad

    2016-01-01

    The present investigation was conducted to evaluate non-invasively, various functional skin parameters i.e., irritation potential, melasma and sebum contents following long term application of topical cream (w/o) loaded with 2% methanolic extract of Ananas comosus L. versus placebo control (base) in healthy adults. Healthy human volunteers (n = 11, aged 20-30 years) were recruited for investigation and written informed consent was taken from each volunteer. In this single blinded study every volunteer applied formulation on one side of face and placebo on the other side of face twice daily for a period of 12 weeks (three months). Different skin parameters i.e., skin irritancy, melasma, and sebum contents were measured on both sides of face at baseline and after two weeks interval, using photometric device Mexameter and Sebumeter in a draught free room with modulated conditions of temperature (22-25°C) and humidity (55-60%). It was evident from the results that no primary skin irritancy was observed with patch test. Besides, statistical interpretation indicates that treatment with formulation is superior to placebo because it significantly (p ≤ 0.05) reduced the skin irritancy, melasma and sebum secretions throughout the study and reaching maximum -20.76 ± 0.89, -54.2 ± 0.37 and -40.71 ± 0.75%, respectively, at the end of study period. Antioxidant activity of extract was 92% compared to standard antioxidant. Conclusively, active cream loaded with fruit extract was well tolerated by all the volunteers and suitable to treat contact dermatitis, greasy skin, acne and seborrheic dermatitis and augmenting beauty and attraction by depigmentation of human skin. So, in the future, there is need to clinically evaluate these formulations in patients with compromised skin functions i.e., contact dermatitis, melasma, and acne vulgaris in order to explore the actual potential of this fruit.

  19. Solar ultraviolet irradiation induces decorin degradation in human skin likely via neutrophil elastase.

    PubMed

    Li, Yong; Xia, Wei; Liu, Ying; Remmer, Henriette A; Voorhees, John; Fisher, Gary J

    2013-01-01

    Exposure of human skin to solar ultraviolet (UV) irradiation induces matrix metalloproteinase-1 (MMP-1) activity, which degrades type I collagen fibrils. Type I collagen is the most abundant protein in skin and constitutes the majority of skin connective tissue (dermis). Degradation of collagen fibrils impairs the structure and function of skin that characterize skin aging. Decorin is the predominant proteoglycan in human dermis. In model systems, decorin binds to and protects type I collagen fibrils from proteolytic degradation by enzymes such as MMP-1. Little is known regarding alterations of decorin in response to UV irradiation. We found that solar-simulated UV irradiation of human skin in vivo stimulated substantial decorin degradation, with kinetics similar to infiltration of polymorphonuclear (PMN) cells. Proteases that were released from isolated PMN cells degraded decorin in vitro. A highly selective inhibitor of neutrophil elastase blocked decorin breakdown by proteases released from PMN cells. Furthermore, purified neutrophil elastase cleaved decorin in vitro and generated fragments with similar molecular weights as those resulting from protease activity released from PMN cells, and as observed in UV-irradiated human skin. Cleavage of decorin by neutrophil elastase significantly augmented fragmentation of type I collagen fibrils by MMP-1. Taken together, these data indicate that PMN cell proteases, especially neutrophil elastase, degrade decorin, and this degradation renders collagen fibrils more susceptible to MMP-1 cleavage. These data identify decorin degradation and neutrophil elastase as potential therapeutic targets for mitigating sun exposure-induced collagen fibril degradation in human skin.

  20. Robust Lentiviral Gene Delivery But Limited Transduction Capacity of Commonly Used Adeno-Associated Viral Serotypes in Xenotransplanted Human Skin.

    PubMed

    Jakobsen, Maria; Askou, Anne Louise; Stenderup, Karin; Rosada, Cecilia; Dagnæs-Hansen, Frederik; Jensen, Thomas G; Corydon, Thomas J; Mikkelsen, Jacob Giehm; Aagaard, Lars

    2015-08-01

    Skin is an easily accessible organ, and therapeutic gene transfer to skin remains an attractive alternative for the treatment of skin diseases. Although we have previously documented potent lentiviral gene delivery to human skin, vectors based on adeno-associated virus (AAV) rank among the most promising gene delivery tools for in vivo purposes. Thus, we compared the potential usefulness of various serotypes of recombinant AAV vectors and lentiviral vectors for gene transfer to human skin in a xenotransplanted mouse model. Vector constructs encoding firefly luciferase were packaged in AAV capsids of serotype 1, 2, 5, 6, 8, and 9 and separately administered by intradermal injection in human skin transplants. For all serotypes, live bioimaging demonstrated low levels of transgene expression in the human skin graft, and firefly luciferase expression was observed primarily in neighboring tissue outside of the graft. In contrast, gene delivery by intradermally injected lentiviral vectors was efficient and led to extensive and persistent firefly luciferase expression within the human skin graft only. The study demonstrates the limited capacity of single-stranded AAV vectors of six commonly used serotypes for gene delivery to human skin in vivo.

  1. Robust Lentiviral Gene Delivery But Limited Transduction Capacity of Commonly Used Adeno-Associated Viral Serotypes in Xenotransplanted Human Skin

    PubMed Central

    Jakobsen, Maria; Askou, Anne Louise; Stenderup, Karin; Rosada, Cecilia; Dagnæs-Hansen, Frederik; Jensen, Thomas G.; Corydon, Thomas J.; Mikkelsen, Jacob Giehm; Aagaard, Lars

    2015-01-01

    Skin is an easily accessible organ, and therapeutic gene transfer to skin remains an attractive alternative for the treatment of skin diseases. Although we have previously documented potent lentiviral gene delivery to human skin, vectors based on adeno-associated virus (AAV) rank among the most promising gene delivery tools for in vivo purposes. Thus, we compared the potential usefulness of various serotypes of recombinant AAV vectors and lentiviral vectors for gene transfer to human skin in a xenotransplanted mouse model. Vector constructs encoding firefly luciferase were packaged in AAV capsids of serotype 1, 2, 5, 6, 8, and 9 and separately administered by intradermal injection in human skin transplants. For all serotypes, live bioimaging demonstrated low levels of transgene expression in the human skin graft, and firefly luciferase expression was observed primarily in neighboring tissue outside of the graft. In contrast, gene delivery by intradermally injected lentiviral vectors was efficient and led to extensive and persistent firefly luciferase expression within the human skin graft only. The study demonstrates the limited capacity of single-stranded AAV vectors of six commonly used serotypes for gene delivery to human skin in vivo. PMID:26204415

  2. Simulation of fluorescent measurements in the human skin

    NASA Astrophysics Data System (ADS)

    Meglinski, Igor V.; Sinichkin, Yurii P.; Utz, Sergei R.; Pilipenko, Helena A.

    1995-05-01

    Reflectance and fluorescence spectroscopy are successfully used for skin disease diagnostics. Human skin optical parameters are defined by its turbid, scattering properties with nonuniform absorption and fluorescence chromophores distribution, its multilayered structure, and variability under different physiological and pathological conditions. Theoretical modeling of light propagation in skin could improve the understanding of these condition and may be useful in the interpretation of in vivo reflectance and autofluorescence (AF) spectra. Laser application in medical optical tomography, tissue spectroscopy, and phototherapy stimulates the development of optical and mathematical light-tissue interaction models allowing to account the specific features of laser beam and tissue inhomogeneities. This paper presents the version of a Monte Carlo method for simulating of optical radiation propagation in biotissue and highly scattering media, allowing for 3D geometry of a medium. The simulation is based on use of Green's function of medium response to single external pulse. The process of radiation propagation is studied in the area with given boundary conditions, taking into account the processes of reflection and refraction at the boundaries of layers inside the medium under study. Results of Monte Carlo simulation were compared with experimental investigations and demonstrated good agreement.

  3. Raman spectroscopy: in vivo quick response code of skin physiological status

    NASA Astrophysics Data System (ADS)

    Vyumvuhore, Raoul; Tfayli, Ali; Piot, Olivier; Le Guillou, Maud; Guichard, Nathalie; Manfait, Michel; Baillet-Guffroy, Arlette

    2014-11-01

    Dermatologists need to combine different clinically relevant characteristics for a better understanding of skin health. These characteristics are usually measured by different techniques, and some of them are highly time consuming. Therefore, a predicting model based on Raman spectroscopy and partial least square (PLS) regression was developed as a rapid multiparametric method. The Raman spectra collected from the five uppermost micrometers of 11 healthy volunteers were fitted to different skin characteristics measured by independent appropriate methods (transepidermal water loss, hydration, pH, relative amount of ceramides, fatty acids, and cholesterol). For each parameter, the obtained PLS model presented correlation coefficients higher than R2=0.9. This model enables us to obtain all the aforementioned parameters directly from the unique Raman signature. In addition to that, in-depth Raman analyses down to 20 μm showed different balances between partially bound water and unbound water with depth. In parallel, the increase of depth was followed by an unfolding process of the proteins. The combinations of all these information led to a multiparametric investigation, which better characterizes the skin status. Raman signal can thus be used as a quick response code (QR code). This could help dermatologic diagnosis of physiological variations and presents a possible extension to pathological characterization.

  4. Raman spectroscopy: in vivo quick response code of skin physiological status.

    PubMed

    Vyumvuhore, Raoul; Tfayli, Ali; Piot, Olivier; Le Guillou, Maud; Guichard, Nathalie; Manfait, Michel; Baillet-Guffroy, Arlette

    2014-01-01

    Dermatologists need to combine different clinically relevant characteristics for a better understanding of skin health. These characteristics are usually measured by different techniques, and some of them are highly time consuming. Therefore, a predicting model based on Raman spectroscopy and partial least square (PLS) regression was developed as a rapid multiparametric method. The Raman spectra collected from the five uppermost micrometers of 11 healthy volunteers were fitted to different skin characteristics measured by independent appropriate methods (transepidermal water loss, hydration, pH, relative amount of ceramides, fatty acids, and cholesterol). For each parameter, the obtained PLS model presented correlation coefficients higher than R2=0.9. This model enables us to obtain all the aforementioned parameters directly from the unique Raman signature. In addition to that, in-depth Raman analyses down to 20 μm showed different balances between partially bound water and unbound water with depth. In parallel, the increase of depth was followed by an unfolding process of the proteins. The combinations of all these information led to a multiparametric investigation, which better characterizes the skin status. Raman signal can thus be used as a quick response code (QR code). This could help dermatologic diagnosis of physiological variations and presents a possible extension to pathological characterization.

  5. In vivo functional human imaging using photoacoustic microscopy: response to ischemic and thermal stimuli

    NASA Astrophysics Data System (ADS)

    Favazza, Christopher; Maslov, Konstantin; Cornelius, Lynn; Wang, Lihong V.

    2010-02-01

    We report results of two in vivo functional human imaging experiments using photoacoustic microscopy. In Experiment 1, the hemodynamic response to an ischemic event was measured. The palm of a volunteer was imaged and a single cross-section was monitored while periodic arterial occlusions were administered using a blood pressure cuff wrapped around the upper arm and inflated to ~280 mmHg. Significant relative decreases in oxygen saturation (sO2) and total hemoglobin (HbT) were observed during periods of ischemia. Upon release of the occlusion, significant relative increases in sO2 and HbT due to post-occlusive reactive hyperemia were recorded. Experiment 2 explored the vascular response to a local, external thermal stimulus. Thermal hyperemia is a common physiological phenomenon and thermoregulation function in which blood flow to the skin is increased to more efficiently exchange heat with the ambient environment. The forearm of a volunteer was imaged and a single cross-section was monitored while the imaged surface was exposed to an elevated temperature of ~46°C. Due to thermal hyperemia, relative increases in sO2 and HbT were measured as the temperature of the surface was raised. These results may contribute as clinically relevant measures of vascular functioning for detection and assessment of vascular related diseases.

  6. Human skin binding and absorption of contaminants from ground and surface water during swimming and bathing

    SciTech Connect

    Wester, R.C.; Maibach, H.I. )

    1989-10-01

    Contaminants exist in ground and surface water. Human skin has the capacity to bind and then absorb these contaminants into the body during swimming and bathing. Powdered human stratum corneum will bind both lipid-soluble (alachlor, polychlorinated biphenyls (PCBs), benzene) and water-soluble (nitroaniline) chemicals. In vitro (Human skin) and in vivo (Rhesus monkey) studies show that these chemicals readily distribute into skin, and then some of the chemical is absorbed into the body. Linearity in binding and absorption exists for nitroaniline over a 10-fold concentration range. Multiple exposure to benzene is at least cumulative. Binding and adsorption can be significant for exposures as short as 30 minutes, and will increase with time. Adsorption with water dilution increased for alachlor, but not for dinoseb. Soap reversed the partitioning of alachlor between human stratum corneum and water. The PCBs could be removed from skin by soap and water for up to 3 hours and the decontamination potential decreased, due to continuing skin absorption. The model that in vitro and in vivo systems used should permit easy estimation of this area of extensive human exposure effect on risk assessment. 5 refs., 9 tabs.

  7. Monitoring changes in the scattering properties of mouse skin with optical coherence tomography during an in vivo glucose tolerance test

    NASA Astrophysics Data System (ADS)

    Kinnunen, M.; Tausta, S.; Myllylä, R.; Vainio, S.

    2007-05-01

    A non-invasive glucose monitoring technique would make evaluation of blood glucose values easier and more convenient. This would help diabetic patients to control their blood glucose values more regularly. A few years ago optical coherence tomography (OCT) was proposed as a non-invasive sensor for monitoring changes in blood glucose concentration. The method is based on monitoring glucose-induced changes in the scattering properties of the target. This article describes how OCT was used to monitor changes in the scattering properties of mouse skin during an in vivo glucose tolerance test. The results show that OCT has the potential to register glucose-induced changes in the optical properties of the sample. However, a commercial OCT device with a probe designed for imaging is not very suitable for non-invasive monitoring of glucose-induced changes in scattering. The problems confronted in this study, possibly originating from the small size of the animals, are discussed in the article.

  8. Direct in vivo strain measurements in human bone-a systematic literature review.

    PubMed

    Al Nazer, R; Lanovaz, J; Kawalilak, C; Johnston, J D; Kontulainen, S

    2012-01-03

    Bone strain is the governing stimuli for the remodeling process necessary in the maintenance of bone's structure and mechanical strength. Strain gages are the gold standard and workhorses of human bone experimental strain analysis in vivo. The objective of this systematic literature review is to provide an overview for direct in vivo human bone strain measurement studies and place the strain results within context of current theories of bone remodeling (i.e. mechanostat theory). We employed a standardized search strategy without imposing any time restriction to find English language studies indexed in PubMed and Web of Science databases that measured human bone strain in vivo. Twenty-four studies met our final inclusion criteria. Seven human bones were subjected to strain measurements in vivo including medial tibia, second metatarsal, calcaneus, proximal femur, distal radius, lamina of vertebra and dental alveolar. Peak strain magnitude recorded was 9096 με on the medial tibia during basketball rebounding and the peak strain rate magnitude was -85,500 με/s recorded at the distal radius during forward fall from standing, landing on extended hands. The tibia was the most exposed site for in vivo strain measurements due to accessibility and being a common pathologic site of stress fracture in the lower extremity. This systematic review revealed that most of the strains measured in vivo in different bones were generally within the physiological loading zone defined by the mechanostat theory, which implies stimulation of functional adaptation necessary to maintain bone mechanical integrity.

  9. Soil adherence to human skin

    SciTech Connect

    Driver, J.H.; Konz, J.J.; Whitmyre, G.K. )

    1989-12-01

    Dermal exposure to soils contaminated with toxic chemicals represents a potential public health hazard. These soils, contaminated with chemicals such as PCBs and dioxins, may be found at various locations throughout the US. Furthermore, dermal contact with pesticide-containing particles and contaminated soil particles is of importance for exposures to agricultural workers who reenter fields after pesticide application. With respect to dermal exposure to pesticide-contaminated particulate matter, several occurrences of human toxicity to ethyl parathion in citrus groves have been reported. These exposures resulted from dermal contact with high concentrations of the toxic transformation product paraoxon in soil dust contaminated as a result of application of pesticide to the overhead foliage of trees. To assess dermal exposure to chemically-contaminated soil at sites of concern, dermal adherence of soil must be determined prior to the assessment of dermal absorption. The purpose of the experiment reported herein was to determine the amount of soil (mg/cm{sup 2}) that adheres to adult hands under various soil conditions. These conditions include the type of soil, the organic content of the soil, and the particle size of the soil.

  10. Influence of nanostructured lipid carriers (NLC) on the physical properties of the Cutanova Nanorepair Q10 cream and the in vivo skin hydration effect.

    PubMed

    Pardeike, Jana; Schwabe, Kay; Müller, Rainer H

    2010-08-30

    Cutanvoa Nanorepair Q10 cream, the first NLC containing cosmetical product introduced to the market in October 2005, was compared to an identical o/w cream without NLC with regards to particle size, melting behaviour, rheological properties and the in vivo effect on skin hydration. The consistency, the spreadability on the skin and the subjective feeling of increase in skin hydration were evaluated using a standardized questionnaire, and compared to hydration data measured. Furthermore, it was shown by epicutaneous patch test that Cutanova Nanorepair Q10 cream has no irritating effects on the skin. By laser diffraction (LD) and differential scanning calorimetry (DSC) measurements it could be shown that NLC are physically stable in Cutanova Nanorepair Q10 cream. After 7 days application of Cutanova Nanorepair Q10 cream and NLC negative control cream an increase in skin hydration could be objectively confirmed by measurements in vivo. From day 28 on the skin hydration measured in the test areas of Cutanova Nanorepair Q10 cream was significantly higher than the skin hydration in the test areas of the NLC negative control cream (p=0.05). The subjective feeling of increase in skin hydration was also rated from the volunteers as superior for Cutanova Nanorepair Q10 cream. The rheological properties of Cutanova Nanorepair Q10 cream contributed to a better subjective impression of consistency and spreadability on the skin than found for NLC negative control cream.

  11. A Full Skin Defect Model to Evaluate Vascularization of Biomaterials In Vivo

    PubMed Central

    Schenck, Thilo L.; Chávez, Myra N.; Condurache, Alexandru P.; Hopfner, Ursula; Rezaeian, Farid; Machens, Hans-Günther; Egaña, José T.

    2014-01-01

    Insufficient vascularization is considered to be one of the main factors limiting the clinical success of tissue-engineered constructs. In order to evaluate new strategies that aim at improving vascularization, reliable methods are required to make the in-growth of new blood vessels into bio-artificial scaffolds visible and quantify the results. Over the past couple of years, our group has introduced a full skin defect model that enables the direct visualization of blood vessels by transillumination and provides the possibility of quantification through digital segmentation. In this model, one surgically creates full skin defects in the back of mice and replaces them with the material tested. Molecules or cells of interest can also be incorporated in such materials to study their potential effect. After an observation time of one’s own choice, materials are explanted for evaluation. Bilateral wounds provide the possibility of making internal comparisons that minimize artifacts among individuals as well as of decreasing the number of animals needed for the study. In comparison to other approaches, our method offers a simple, reliable and cost effective analysis. We have implemented this model as a routine tool to perform high-resolution screening when testing vascularization of different biomaterials and bio-activation approaches. PMID:25226211

  12. Inflammation modulates human HDL composition and function in vivo

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inflammation may directly impair HDL functions, in particular reverse cholesterol transport (RCT), but limited data support this concept in humans. Our study was designed to investigate this relationship. We employed low-dose human endotoxemia to assess the effects of inflammation on HDL and RCT-rel...

  13. Rapid mesoscale multiphoton microscopy of human skin

    PubMed Central

    Balu, Mihaela; Mikami, Hideharu; Hou, Jue; Potma, Eric O.; Tromberg, Bruce J.

    2016-01-01

    We present a multiphoton microscope designed for mesoscale imaging of human skin. The system is based on two-photon excited fluorescence and second-harmonic generation, and images areas of ~0.8x0.8 mm2 at speeds of 0.8 fps (800x800 pixels; 12 frame averages) for high signal-to-noise ratio, with lateral and axial resolutions of 0.5µm and 3.3µm, respectively. The main novelty of this instrument is the design of the scan head, which includes a fast galvanometric scanner, optimized relay optics, a beam expander and high NA objective lens. Computed aberrations in focus are below the Marechal criterion of 0.07λ rms for diffraction-limited performance. We demonstrate the practical utility of this microscope by ex-vivo imaging of wide areas in normal human skin. PMID:27895980

  14. Comparative mutagenesis of human cells in vivo and in vitro

    SciTech Connect

    Thilly, W.G.

    1990-01-01

    Our goal is to develop the tools of mutational spectrometry in order to discover the cause(s) of genetic change in somatic and germinal cells in humans. Our study of the spectrum of point mutations in human mitochrondrial DNA sequences has revealed that there are multiple point mutation hotspots in each of four separate sequences in the mitochrondrial genome. These spectra were revealed by a combination of high fidelity PCR (modified T{sub 7} polymerase) and denaturing gradient gel electrophoresis which has a limit of detection of about 10{sup {minus}3}. There appear to be identical hotspot mutations in both cultured B cell and fresh human blood T cell samples.

  15. Validation of the cantharidin-induced skin blister as an in vivo model of inflammation

    PubMed Central

    Dinh, Phong Huy Duc; Corraza, Francis; Mestdagh, Kristel; Kassengera, Zaina; Doyen, Virginie; Michel, Olivier

    2011-01-01

    AIM Pharmacological profiling techniques, such as the cantharidin-induced skin blister, may be used to assess the anti-inflammatory properties of novel drugs. However, no data are available on the reproducibility of this technique or on the blocking effect of anti-inflammatory drugs, such as anti-TNF and corticosteroids. METHODS A group of 30 healthy subjects were randomized into three parallel groups treated with placebo, oral methylprednisolone 20 mg day−1 for 7 days or anti-tumour necrosis factor (TNF) (adalimumab, Humira®, Abbott) 40 mg s.c. single dose. A first blister was induced at baseline and collected, immediately before the start of treatment and a second blister was obtained 7 days after the start of treatment. The total number of cells, the cell viability and the differential cell count were evaluated by two independent observers, who were blind to treatment. anova was used to compare change from baseline among the three groups before pairwise comparisons. RESULTS Among the placebo group, there was no significant difference in the total cell count, neutrophils, eosinophils and monocytes between day 1 and day 7. Methylprednisolone inhibited the eosinophil influx in mean % (95% CI) (−1.0 (−1.7, −0.3); P < 0.02) and absolute (P < 0.02) values, while anti-TNF inhibited the neutrophil influx in mean % (95% CI) (−19.3 (−29.5, −9.1); P < 0.01) and absolute (P < 0.05) values. CONCLUSIONS The cantharidin-induced skin blister is a safe, well tolerated and reproducible procedure. Pre-treatment with anti-TNF or methylprednisolone inhibited the neutrophilic or eosinophilic trafficking, respectively. It could be useful in profiling anti-inflammatory drugs regarding their effects on the cellular inflammatory response. PMID:21595743

  16. Crocetin protects ultraviolet A-induced oxidative stress and cell death in skin in vitro and in vivo.

    PubMed

    Ohba, Takuya; Ishisaka, Mitsue; Tsujii, Saori; Tsuruma, Kazuhiro; Shimazawa, Masamitsu; Kubo, Koya; Umigai, Naofumi; Iwawaki, Takao; Hara, Hideaki

    2016-10-15

    Crocetin, the aglycone of crocin, is a carotenoid found in fruits of gardenia (Gardeina jasminoides Ellis) and saffron (Crocus sativus L.). We investigated the protective effects of crocetin against ultraviolet-A (UV-A)-induced skin damage and explored the underlying mechanism. Human skin-derived fibroblasts cells (NB1-RGB) were damaged by exposure to UV-A irradiation (10J/cm(2)). Crocetin protected these cells against cell death and reduced the production of reactive oxygen species induced by UV-A irradiation. Crocetin treatment also suppressed induction of caspase-3 activation by UV-A irradiation. The effects of crocetin against oxidative stress were also examined by imaging of Keap1-dependent oxidative stress detector (OKD) mice. UV-A irradiation upregulated oxidative stress in the OKD mice skin, while crocetin administration (100mg/kg, p.o.) ameliorated this oxidative stress. Crocetin administration also decreased lipid peroxidation in the skin. These findings suggest that crocetin its observed protective effects against UV-A induced skin damage by reducing reactive oxygen species production and cell apoptosis.

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

    PubMed

    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.

  18. Noninvasive evaluation of collagen and hemoglobin contents and scattering property of in vivo keloid scars and normal skin using diffuse reflectance spectroscopy: pilot study

    NASA Astrophysics Data System (ADS)

    Tseng, Sheng-Hao; Hsu, Chao-Kai; Yu-Yun Lee, Julia; Tzeng, Shih-Yu; Chen, Wan-Rung; Liaw, Yu-Kai

    2012-07-01

    Collagen is a rich component in skin that provides skin structure integrity; however, its contribution to the absorption and scattering properties of various types of skin has not been extensively studied. We considered the contribution of the collagen to the absorption spectrum of in vivo normal skin and keloids of 12 subjects derived from our diffuse reflectance spectroscopy (DRS) system in the wavelength range from 550 to 860 nm. It was found that the collagen concentration, the hemoglobin oxygen saturation, and the reduced scattering coefficient of keloids were remarkably different from that of normal skin. Our results suggest that our DRS system could assist clinicians in understanding the functional and structural condition of keloid scars. In the future, we will evaluate the accuracy of our system in the keloid diagnosis and investigate the applicability of our system for other skin-collagen-related studies.

  19. Noninvasive evaluation of collagen and hemoglobin contents and scattering property of in vivo keloid scars and normal skin using diffuse reflectance spectroscopy: pilot study.

    PubMed

    Tseng, Sheng-Hao; Hsu, Chao-Kai; Yu-Yun Lee, Julia; Tzeng, Shih-Yu; Chen, Wan-Rung; Liaw, Yu-Kai

    2012-07-01

    Collagen is a rich component in skin that provides skin structure integrity; however, its contribution to the absorption and scattering properties of various types of skin has not been extensively studied. We considered the contribution of the collagen to the absorption spectrum of in vivo normal skin and keloids of 12 subjects derived from our diffuse reflectance spectroscopy (DRS) system in the wavelength range from 550 to 860 nm. It was found that the collagen concentration, the hemoglobin oxygen saturation, and the reduced scattering coefficient of keloids were remarkably different from that of normal skin. Our results suggest that our DRS system could assist clinicians in understanding the functional and structural condition of keloid scars. In the future, we will evaluate the accuracy of our system in the keloid diagnosis and investigate the applicability of our system for other skin-collagen-related studies.

  20. Modeling normal and malignant human hematopoiesis in vivo through newborn NSG xenotransplantation.

    PubMed

    Ishikawa, Fumihiko

    2013-12-01

    Various strains of immune-compromised mice have been developed to investigate human normal and malignant stem cells in vivo. NOD/SCID mice harboring complete null mutation of Il2rg (NSG mice) lack T cells, B cells, and NK cells, and support high levels of engraftment by human cord blood hematopoietic stem cells (CB HSCs) and acute myeloid leukemia stem cells (AML LSCs). In addition to achieving high levels of human hematopoietic cell engraftment, use of newborn NSG mice as recipients has enabled the investigation into how human CB HSCs generate mature immune subsets in vivo. Moreover, through establishing an in vivo model of human primary AML by xenotransplantation of human LSCs into newborn NSG mice, functional properties of human AML such as cell cycle, location, and self-renewal capacity can be examined in vivo. Newborn NSG xenogeneic transplantation model may facilitate the understanding of human normal and malignant hematopoiesis and contribute to the development of novel therapies against hematologic diseases.

  1. In vivo cellular visualization of the human retina using optical coherence tomography and adaptive optics

    SciTech Connect

    Olivier, S S; Jones, S M; Chen, D C; Zawadzki, R J; Choi, S S; Laut, S P; Werner, J S

    2006-01-05

    Optical coherence tomography (OCT) sees the human retina sharply with adaptive optics. In vivo cellular visualization of the human retina at micrometer-scale resolution is possible by enhancing Fourier-domain optical-coherence tomography with adaptive optics, which compensate for the eye's optical aberrations.

  2. Laboratory production in vivo of infectious human papillomavirus type 11

    SciTech Connect

    Kreider, J.W.; Howett, M.K.; Leure-Dupree, A.E.; Zaino, R.J.; Weber, J.A.

    1987-02-01

    Human papillomaviruses (HPV) induce among patients natural lesions which produce small amounts of virus. Infection of human cell cultures does not lead to the multiplication of virus, which also does not replicate in experimental animals. The authors have developed a unique system for the laboratory production of HPV type 11 (HPV-11). Fragments of human neonatal foreskin were infected with an extract of naturally occurring human vulvar condylomata and grafted beneath the renal capsule of athymic mice. Later (3 to 5 months), condylomatous cysts developed from those grafts. Nuclei of koilocytotic cells contained large amounts of capsid antigen and intranuclear virions. The experimentally induced condylomata were homogenized, and the virions were extracted and used to infect another generation of human foreskin grafts in athymic mice. The HPV-11 DNA content and infectivity of the natural and experimental condylomata were similar. Extracts of experimental condylomata were subjected to differential ultracentrifugation and sedimentation in CsCl density gradients. A single, opalescent band was visible at a density of 1.34 g/ml. It contained HPV virions with HPV-11 DNA. This report is the first demonstration of the laboratory production of an HPV.

  3. Targeting of human glioma xenografts in vivo utilizing radiolabeled antibodies

    SciTech Connect

    Williams, J.A.; Wessels, B.W.; Wharam, M.D.; Order, S.E.; Wanek, P.M.; Poggenburg, J.K.; Klein, J.L. )

    1990-06-01

    Radiolabeled antibodies provide a potential basis for selective radiotherapy of human gliomas. We have measured tumor targeting by radiolabeled monoclonal and polyclonal antibodies directed against neuroectodermal and tumor-associated antigens in nude mice bearing human glioma xenografts. Monoclonal P96.5, a mouse IgG2a immunoglobulin, defines an epitope of a human melanoma cell surface protein, and specifically binds the U-251 human glioma as measured by immunoperoxidase histochemistry. 111In-radiolabeled P96.5 specifically targets the U-251 human glioma xenograft and yields 87.0 microCuries (microCi) of tumor activity per gram per 100 microCi injected activity compared to 4.5 microCi following administration of radiolabeled irrelevant monoclonal antibody. Calculations of targeting ratios demonstrate deposited dose to be 11.6 times greater with radiolabeled P96.5 administration compared to irrelevant monoclonal antibody. The proportion of tumor dose found in normal organs is less than 10%, further supporting specific targeting of the human glioma xenograft by this antibody. Monoclonal antibody ZME018, which defines a second melanoma-associated antigen, and polyclonal rabbit antiferritin, which defines a tumor-associated antigen, demonstrate positive immunoperoxidase staining of the tumor, but comparatively decreased targeting. When compared to the 111In-radiolabeled antibody, 90Y-radiolabeled P96.5 demonstrates comparable tumor targeting and percentages of tumor dose found in normal organs. To test the therapeutic potential of 90Y-radiolabeled P96.5, tumors and normal sites were implanted with miniature thermoluminescent dosimeters (TLD). Seven days following administration of 100 microCi 90Y-radiolabeled P96.5, average absorbed doses of 3770, 980, 353, and 274 cGy were observed in tumor, liver, contralateral control site, and total body, respectively.

  4. MEMS-based handheld confocal microscope for in-vivo skin imaging

    PubMed Central

    Arrasmith, Christopher L.; Dickensheets, David L.; Mahadevan-Jansen, Anita

    2010-01-01

    This paper describes a handheld laser scanning confocal microscope for skin microscopy. Beam scanning is accomplished with an electromagnetic MEMS bi-axial micromirror developed for pico projector applications, providing 800x600 (SVGA) resolution at 56 frames per second. The design uses commercial objective lenses with an optional hemisphere front lens, operating with a range of numerical aperture from NA=0.35 to NA=1.1 and corresponding diagonal field of view ranging from 653 μm to 216 μm. Using NA=1.1 and a laser wavelength of 830 nm we measured the axial response to be 1.14 μm full width at half maximum, with a corresponding 10%-90% lateral edge response of 0.39 μm. Image examples showing both epidermal and dermal features including capillary blood flow are provided. These images represent the highest resolution and frame rate yet achieved for tissue imaging with a MEMS bi-axial scan mirror. PMID:20389391

  5. In vivo evaluating skin doses for lung cancer patients undergoing volumetric modulated arc therapy treatment.

    PubMed

    Tseng, Hsien-Chun; Pan, Lung-Kang; Chen, Hsin-Yu; Liu, Wen-Shan; Hsu, Chang-Chieh; Chen, Chien-Yi

    2015-01-01

    This study is the first to use 10- to 90-kg tissue-equivalent phantoms as patient surrogates to measure peripheral skin doses (Dskin) in lung cancer treatment through Volumetric Modulated Arc Therapy of the Axesse linac. Five tissue-equivalent and Rando phantoms were used to simulate lung cancer patients using the thermoluminescent dosimetry (TLD-100H) approach. TLD-100H was calibrated using 6 MV photons coming from the Axesse linac. Then it was inserted into phantom positions that closely corresponded with the position of the represented organs and tissues. TLDs were measured using the Harshaw 3500 TLD reader. The ICRP 60 evaluated the mean Dskin to the lung cancer for 1 fraction (7 Gy) undergoing VMAT. The Dskin of these phantoms ranged from 0.51±0.08 (10-kg) to 0.22±0.03 (90-kg) mSv/Gy. Each experiment examined the relationship between the Dskin and the distance from the treatment field. These revealed strong variations in positions close to the tumor center. The correlation between Dskin and body weight was Dskin (mSv) = -0.0034x + 0.5296, where x was phantom's weight in kg. R2 is equal to 0.9788. This equation can be used to derive an equation for lung cancer in males. Finally, the results are compared to other published research. These findings are pertinent to patients, physicians, radiologists, and the public.

  6. Comparative mutagenesis of human cells in vivo and in vitro

    SciTech Connect

    Thilly, W.G.

    1992-05-01

    This report discusses measuring methods of point mutations; high density cell cultures for low dose studies; measurement and sequence determination of mutations in DNA; the mutational spectra of styrene oxide and ethlyene oxide in TK-6 cells; mutational spectrum of Cr in human lymphoblast cells; mutational spectra of radon in TK-6 cells; and the mutational spectra of smokeless tobacco. (CBS)

  7. Application of optical methods to characterize textile materials and their influence on the human skin

    NASA Astrophysics Data System (ADS)

    Strese, Helene; Kuck, Monika; Benken, Rainer; Schanzer, Sabine; Richter, Heike; Fluhr, Joachim W.; Meinke, Martina C.; Benderoth, Christian; Frankowski, Gottfried; Sterry, Wolfram; Lademann, Juergen

    2011-04-01

    The skin is not only the largest organ of the human body, but it is also a barrier to the environment. The major part of the human skin is in constant contact with textile materials. The objective of this study was to characterize textile materials and to investigate their influence on the skin properties. For this purpose, two different textile materials (polyamide and polyester) were objectively characterized by optical coherence tomography and surface structure 3D-profilometry. In addition, subjective textile properties like haptic sensation and stiffness, as tactile characteristics felt by volunteers, were analyzed. The objective textile characteristics and subjective parameters were compared to the barrier properties measured by in vivo laser scanning microscopy . Comparable results were achieved between barrier properties and subjective assessment in relation to the textile characteristics in favor of the polyester fabric. Consequently, the optical method used in dermatology for the analysis of the skin can be applied to characterize and evaluate textile fabrics and their interaction with human skin in vivo.

  8. Regulation of extracellular matrix proteins and integrin cell substratum adhesion receptors on epithelium during cutaneous human wound healing in vivo.

    PubMed Central

    Juhasz, I.; Murphy, G. F.; Yan, H. C.; Herlyn, M.; Albelda, S. M.

    1993-01-01

    Although changes in extracellular matrix proteins during wound healing have been well documented, little is known about the regulation of corresponding extracellular matrix adhesion receptors (integrins). To study this process in a human in vivo model, full thickness human skin grafts were transplanted onto severe combined immunodeficient mice and deep excisional wounds involving both the epidermal and dermal layers were then made. The changes in the expression of cell matrix proteins and epithelial integrins over time were analyzed with specific antibodies using immunohistochemistry. Wounding was associated with alterations in extracellular matrix proteins, namely, loss of laminin and type IV collagen in the region of the wound and expression of tenascin and fibronectin. Changes were also noted in the integrins on the migrating keratinocytes. There was marked up-regulation of the alpha v subunit and de novo expression of the fibronectin receptor (alpha 5 beta 1) during the stage of active migration (days 1 to 3 after wounding). In the later stages of wound healing, after epithelial integrity had been established, redistribution of the alpha 2, alpha 3, alpha 6, and beta 4 collagen/laminin-binding integrin subunits to suprabasal epidermal layers was noted. Thus, during cutaneous wound healing, keratinocytes up-regulate fibronectin/fibrinogen-binding integrins and redistribute collagen/laminin-binding integrins. This study demonstrates that the human skin/severe combined immunodeficient chimera provides a useful model to study events during human wound repair. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7694470

  9. Eravacycline Pharmacokinetics and Challenges in Defining Humanized Exposure In Vivo

    PubMed Central

    Monogue, Marguerite L.

    2016-01-01

    We assessed the pharmacokinetic profile of eravacycline, a novel antibiotic of the tetracycline class, and determined the dose in an immunocompetent murine thigh infection model that would provide free-drug exposure similar to that observed in humans after the administration of 1 mg/kg intravenously (i.v.) every 12 h (q12h). Eravacycline demonstrated a nonlinear protein-binding profile. The 2.5-mg/kg i.v. q12h dose in mice resulted in an area under the concentration-time curve for the free, unbound fraction of the drug of 1.64 mg · h/liter, which closely resembles the human exposure level. PMID:27353264

  10. (Comparative) mutagenesis of human cells in vivo and in vitro

    SciTech Connect

    Thilly, W.G.

    1989-01-01

    We have combined Fischer and Lerman's denaturing gradient gel electrophoresis, high fidelity DNA amplification, and quantitative mutational measurements in a 104 bp sequence within the third exon of the hprt gene in cultured human TK6 cells in order to observe predominant point mutations. We have now characterized the mutations arising spontaneously or after treatment with ICR-191, MNNG, benzo({alpha})pyrene diol epoxide, ultraviolet light, hyperbaric oxygen, and hydrogen peroxide.

  11. Different growth factor requirements for human Th2 cells may reflect in vivo induced anergy.

    PubMed Central

    Van Reijsen, F C; Wijburg, O L; Gebhardt, M; Van Ieperen-Van Dijk, A G; Betz, S; Poellabauer, E M; Thepen, T; Bruijnzeel-Koomen, C A; Mudde, G C

    1994-01-01

    hypothesize that the Th2 phenotype of AD skin-derived, allergen-specific T cells may be induced in vivo by LC, which lack CD80, and therefore do not provide secondary signals through CD28-CD80 interaction. PMID:7923875

  12. Bipolar cellular morphology of malignant melanoma in unstained human melanoma skin tissue

    NASA Astrophysics Data System (ADS)

    Zhang, Kai; Zhang, Wenkai; Yang, Chia-Yi; Yang, Haw

    2009-03-01

    Microstructures of unstained human melanoma skin tissues have been examined by multimodal nonlinear optical microscopy. The polarized shape of the individual melanoma cell can be readily recognized-a phenotype that has been identified in laboratory cultures as characteristic of proliferating melanocytes but has not been demonstrated in clinical instances. The results thus provide snapshots of invading melanoma cells in their native environment and suggest a practical means of connecting in vitro laboratory studies to in vivo processes.

  13. Influence of water dilution on percutaneous absorption of N-vinyl-2-pyrrolidone in vivo and ex vivo in rats and ex vivo in humans.

    PubMed

    Marquet, Fabrice; Payan, Jean-Paul; Beydon, Dominique; Wathier, Ludivine; Ferrari, Elisabeth; Grandclaude, Marie-Christine

    2015-11-01

    N-vinyl-2-pyrrolidone (NVP) is mainly used as a monomer in the production of polyvinylpyrrolidone or copolymers. Percutaneous absorption is an important source of exposure in the work environment. However, few studies have investigated this route of absorption. In this study, percutaneous absorption of neat or aqueous NVP solutions was measured in vivo and ex vivo in rats, and ex vivo in humans. Penetration and absorption fluxes were very similar following in vivo exposure to neat NVP (0.54 and 0.43 mg/cm(2)/h, respectively). Exposing rats to a 50% aqueous solution of NVP increased both fluxes threefold (to 1.48 and 1.55 mg/cm(2)/h, respectively). Ex vivo, the absorption flux increased with solutions from 10 to 25% of NVP, reached a plateau (between 25 and 50% in rat, 25 and 75% in human) and then decreased with neat NVP. In vivo and ex vivo absorption fluxes measured using rat skin were similar, supporting the hypothesis that the ex vivo measurements were a good representation of what was observed in vivo. Thus, for humans, the ex vivo measurements are likely the same as would be determined in vivo.

  14. Preparation of Inactivated Human Skin Using High Hydrostatic Pressurization for Full-Thickness Skin Reconstruction

    PubMed Central

    Liem, Pham Hieu; Morimoto, Naoki; Mahara, Atsushi; Jinno, Chizuru; Shima, Koji; Ogino, Shuichi; Sakamoto, Michiharu; Kakudo, Natsuko; Inoie, Masukazu; Kusumoto, Kenji; Fujisato, Toshia; Suzuki, Shigehiko; Yamaoka, Tetsuji

    2015-01-01

    We have reported that high-hydrostatic-pressure (HHP) technology is safe and useful for producing various kinds of decellularized tissue. However, the preparation of decellularized or inactivated skin using HHP has not been reported. The objective of this study was thus to prepare inactivated skin from human skin using HHP, and to explore the appropriate conditions of pressurization to inactivate skin that can be used for skin reconstruction. Human skin samples of 8 mm in diameter were packed in bags filled with normal saline solution (NSS) or distilled water (DW), and then pressurized at 0, 100, 150, 200 and 1000 MPa for 10 minutes. The viability of skin after HHP was evaluated using WST-8 assay. Outgrowth cells from pressurized skin and the viability of pressurized skin after cultivation for 14 days were also evaluated. The pressurized skin was subjected to histological evaluation using hematoxylin and eosin staining, scanning electron microscopy (SEM), immunohistochemical staining of type IV collagen for the basement membrane of epidermis and capillaries, and immunohistochemical staining of von Willebrand factor (vWF) for capillaries. Then, human cultured epidermis (CE) was applied on the pressurized skin and implanted into the subcutis of nude mice; specimens were subsequently obtained 14 days after implantation. Skin samples pressurized at more than 200 MPa were inactivated in both NSS and DW. The basement membrane and capillaries remained intact in all groups according to histological and immunohistological evaluations, and collagen fibers showed no apparent damage by SEM. CE took on skin pressurized at 150 and 200 MPa after implantation, whereas it did not take on skin pressurized at 1000 MPa. These results indicate that human skin could be inactivated after pressurization at more than 200 MPa, but skin pressurized at 1000 MPa had some damage to the dermis that prevented the taking of CE. Therefore, pressurization at 200 MPa is optimal for preparing

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

    PubMed

    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.

  16. Recombinant human epidermal growth factor accelerates the proliferation of irradiated human fibroblasts and keratinocytes in vitro and in vivo.

    PubMed

    Ryu, Seung-Hee; Moon, Soo Young; Yang, Youn-Joo; Moon, Sun Rock; Hong, Joon Pio; Choi, Jene; Lee, Sang-Wook

    2009-11-01

    Irradiation causes the impaired proliferation of cells lining mucosal membranes. Epidermal growth factor (EGF) facilitates proliferation of various skin cells; however, the wound healing effects of EGF on radiation-damaged cells is less well known. To evaluate the effects of recombinant human EGF (rhEGF) on the proliferation of cells following irradiation, we tested two types of fibroblast cell lines and one keratinocyte cell line. The viable cell numbers were significantly increased by rhEGF treatment for 24 h immediately after 8 Gy of irradiation. The most effective dose of rhEGF was 10 nM in all cell lines used in this study. The percentage of BrdU-labeled cells was also significantly increased by rhEGF treatment. To evaluate the effects of rhEGF on radiation-induced oral mucosal damage in BALB/c mice, we systematically injected 1 mg/kg/day EGF for three days after 17 Gy of irradiation. Administered rhEGF ameliorated radiation-induced mucosal damage in vivo. rhEGF significantly increased the epithelial cell layer thickness and the proliferation of basal layer cells as detected by Ki-67 staining. Our results suggest that rhEGF can be a therapeutic treatment for radiation-induced wounds by stimulating the proliferation of fibroblasts and keratinocytes following irradiation.

  17. In vivo analysis of human nucleoporin repeat domain interactions

    PubMed Central

    Xu, Songli; Powers, Maureen A.

    2013-01-01

    The nuclear pore complex (NPC), assembled from ∼30 proteins termed nucleoporins (Nups), mediates selective nucleocytoplasmic trafficking. A subset of nucleoporins bear a domain with multiple phenylalanine–glycine (FG) motifs. As binding sites for transport receptors, FG Nups are critical in translocation through the NPC. Certain FG Nups are believed to associate via low-affinity, cohesive interactions to form the permeability barrier of the pore, although the form and composition of this functional barrier are debated. We used green fluorescent protein–Nup98/HoxA9 constructs with various numbers of repeats and also substituted FG domains from other nucleoporins for the Nup98 domain to directly compare cohesive interactions in live cells by fluorescence recovery after photobleaching (FRAP). We find that cohesion is a function of both number and type of FG repeats. Glycine–leucine–FG (GLFG) repeat domains are the most cohesive. FG domains from several human nucleoporins showed no interactions in this assay; however, Nup214, with numerous VFG motifs, displayed measurable cohesion by FRAP. The cohesive nature of a human nucleoporin did not necessarily correlate with that of its yeast orthologue. The Nup98 GLFG domain also functions in pore targeting through binding to Nup93, positioning the GLFG domain in the center of the NPC and supporting a role for this nucleoporin in the permeability barrier. PMID:23427268

  18. Dentinal fluid dynamics in human teeth, in vivo.

    PubMed

    Ciucchi, B; Bouillaguet, S; Holz, J; Pashley, D

    1995-04-01

    Cavities were prepared in human premolars scheduled for extraction for orthodontic reasons. The smear layer was removed from the dentin surface by acid etching, and the cavity was sealed using a hollow chamber. The chamber was filled with sterile saline solution and connected via tubing to a hydraulic circuit featuring an adjustable pressure reservoir and a device that measures fluid movement across dentin. In the absence of any exogenous pressure, all cavities exhibited an outward fluid flow rate of 0.36 microliters min-1 cm-2. As exogenous pressure was applied to the cavity, the outward flow slowed. The exogenous pressure that stopped outward fluid flow was taken to be equal to normal pulpal tissue pressure. The mean value was 14.1 cm H2O in five teeth. This simple method permits measurement of dentinal fluid flux, the hydraulic conductance of dentin, and estimates pulpal tissue pressure.

  19. Application of XRF to measure strontium in human bone in vivo

    SciTech Connect

    Wielopolski, L.; Vartsky, D.; Yasumura, S.; Cohn, S.H.

    1982-01-01

    As a basis for better understanding the role that Sr fulfills in human body, it is desirable to measure directly the main Sr store in human body. Although strontium is omnipresent in human tissues, 99% is stored inthe mineral portion of the bone. In the present study x-ray fluorescence (XRF) was applied to measure the strontium content of the tibial shaft in vivo. The feasibility studies showed that normal levels of stable strontium in the bone can be measured successfully.

  20. Volatile oils of Chinese crude medicines exhibit antiparasitic activity against human Demodex with no adverse effects in vivo

    PubMed Central

    LIU, JI-XIN; SUN, YAN-HONG; LI, CHAO-PIN

    2015-01-01

    Demodex is a type of permanent obligatory parasite, which can be found on the human body surface. Currently, drugs targeting Demodex usually result in adverse effects and have a poor therapeutic effect. Thus, the aim of the present study was to investigate the use of Chinese crude medicine volatile oils for targeting and inhibiting Demodex in vitro. The volatile oils of six Chinese crude medicines were investigated, including clove, orange fruit, Manchurian wildginger, cinnamon bark, Rhizome Alpiniae Officinarum and pricklyash peel, which were extracted using a distillation method. The exercise status of Demodex folliculorum and Demodex brevis and the antiparasitic effects of the volatile oils against the two species were observed using microscopy. A skin irritation test was used to examine the irritation intensity of the volatile oils. In addition, an acute toxicity test was utilized to observe the toxicity effects of the volatile oils on the skin. Xin Fumanling ointment was employed as a positive control to identify the therapeutic effects of the volatile oils. The results indicated that all six volatile oils were able to kill Demodex efficiently. In particular, the clove volatile oil was effective in inducing optimized anti-Demodex activity. The lethal times of the volatile oils were significantly decreased compared with the Xin Fumanling ointment (P<0.05). Furthermore, the skin irritation test results indicated that the clove volatile oil did not trigger any irritation (0.2 and 0.3 points for intact and scratched skin, respectively), and had a safety equal to that of distilled water. There were not any adverse effects observed following application of the clove volatile oil on the intact or scratched skin. In conclusion, the volatile oils of Chinese crude medicines, particularly that of clove, demonstrated an evident anti-Demodex activity and were able to kill Demodex effectively and safely in vivo. PMID:25780426

  1. Volatile oils of Chinese crude medicines exhibit antiparasitic activity against human Demodex with no adverse effects in vivo.

    PubMed

    Liu, Ji-Xin; Sun, Yan-Hong; Li, Chao-Pin

    2015-04-01

    Demodex is a type of permanent obligatory parasite, which can be found on the human body surface. Currently, drugs targeting Demodex usually result in adverse effects and have a poor therapeutic effect. Thus, the aim of the present study was to investigate the use of Chinese crude medicine volatile oils for targeting and inhibiting Demodex in vitro. The volatile oils of six Chinese crude medicines were investigated, including clove, orange fruit, Manchurian wildginger, cinnamon bark, Rhizome Alpiniae Officinarum and pricklyash peel, which were extracted using a distillation method. The exercise status of Demodex folliculorum and Demodex brevis and the antiparasitic effects of the volatile oils against the two species were observed using microscopy. A skin irritation test was used to examine the irritation intensity of the volatile oils. In addition, an acute toxicity test was utilized to observe the toxicity effects of the volatile oils on the skin. Xin Fumanling ointment was employed as a positive control to identify the therapeutic effects of the volatile oils. The results indicated that all six volatile oils were able to kill Demodex efficiently. In particular, the clove volatile oil was effective in inducing optimized anti-Demodex activity. The lethal times of the volatile oils were significantly decreased compared with the Xin Fumanling ointment (P<0.05). Furthermore, the skin irritation test results indicated that the clove volatile oil did not trigger any irritation (0.2 and 0.3 points for intact and scratched skin, respectively), and had a safety equal to that of distilled water. There were not any adverse effects observed following application of the clove volatile oil on the intact or scratched skin. In conclusion, the volatile oils of Chinese crude medicines, particularly that of clove, demonstrated an evident anti-Demodex activity and were able to kill Demodex effectively and safely in vivo.

  2. Parameterization using Fourier series expansion of the diffuse reflectance of human skin to vary the concentration of the melanocytes

    NASA Astrophysics Data System (ADS)

    Narea, J. Freddy; Muñoz, Aarón A.; Castro, Jorge; Muñoz, Rafael A.; Villalba, Caroleny E.; Martinez, María. F.; Bravo, Kelly D.

    2013-11-01

    Human skin has been studied in numerous investigations, given the interest in knowing information about physiology, morphology and chemical composition. These parameters can be determined using non invasively optical techniques in vivo, such as the diffuse reflectance spectroscopy. The human skin color is determined by many factors, but primarily by the amount and distribution of the pigment melanin. The melanin is produced by the melanocytes in the basal layer of the epidermis. This research characterize the spectral response of the human skin using the coefficients of Fourier series expansion. Simulating the radiative transfer equation for the Monte Carlo method to vary the concentration of the melanocytes (fme) in a simplified model of human skin. It fits relating the Fourier series coefficient a0 with fme. Therefore it is possible to recover the skin biophysical parameter.

  3. Human skin pigmentation, migration and disease susceptibility

    PubMed Central

    Jablonski, Nina G.; Chaplin, George

    2012-01-01

    Human skin pigmentation evolved as a compromise between the conflicting physiological demands of protection against the deleterious effects of ultraviolet radiation (UVR) and photosynthesis of UVB-dependent vitamin D3. Living under high UVR near the equator, ancestral Homo sapiens had skin rich in protective eumelanin. Dispersals outside of the tropics were associated with positive selection for depigmentation to maximize cutaneous biosynthesis of pre-vitamin D3 under low and highly seasonal UVB conditions. In recent centuries, migrations and high-speed transportation have brought many people into UVR regimes different from those experienced by their ancestors and, accordingly, exposed them to new disease risks. These have been increased by urbanization and changes in diet and lifestyle. Three examples—nutritional rickets, multiple sclerosis (MS) and cutaneous malignant melanoma (CMM)—are chosen to illustrate the serious health effects of mismatches between skin pigmentation and UVR. The aetiology of MS in particular provides insight into complex and contingent interactions of genetic and environmental factors necessary to trigger lethal disease states. Low UVB levels and vitamin D deficiencies produced by changes in location and lifestyle pose some of the most serious disease risks of the twenty-first century. PMID:22312045

  4. Drosophila as an In Vivo Model for Human Neurodegenerative Disease

    PubMed Central

    McGurk, Leeanne; Berson, Amit; Bonini, Nancy M.

    2015-01-01

    With the increase in the ageing population, neurodegenerative disease is devastating to families and poses a huge burden on society. The brain and spinal cord are extraordinarily complex: they consist of a highly organized network of neuronal and support cells that communicate in a highly specialized manner. One approach to tackling problems of such complexity is to address the scientific questions in simpler, yet analogous, systems. The fruit fly, Drosophila melanogaster, has been proven tremendously valuable as a model organism, enabling many major discoveries in neuroscientific disease research. The plethora of genetic tools available in Drosophila allows for exquisite targeted manipulation of the genome. Due to its relatively short lifespan, complex questions of brain function can be addressed more rapidly than in other model organisms, such as the mouse. Here we discuss features of the fly as a model for human neurodegenerative disease. There are many distinct fly models for a range of neurodegenerative diseases; we focus on select studies from models of polyglutamine disease and amyotrophic lateral sclerosis that illustrate the type and range of insights that can be gleaned. In discussion of these models, we underscore strengths of the fly in providing understanding into mechanisms and pathways, as a foundation for translational and therapeutic research. PMID:26447127

  5. Human skin organ culture for assessment of chemically induced skin damage

    PubMed Central

    Varani, James

    2015-01-01

    The move away from animal models for skin safety testing is inevitable. It is a question of when, not if. As skin safety studies move away from traditional animal-based approaches, a number of replacement technologies are becoming available. Human skin in organ culture is one such technology. Organ-cultured skin has several features that distinguish it from other technologies. First and foremost, organ-cultured skin is real skin. Almost by definition, therefore, it approximates the intact skin better than other alternative models. Organ culture is an easy-to-use and relatively inexpensive approach to preclinical safety assessment. Although organ culture is not likely to replace high-throughput enzyme assays or monolayer culture/skin equivalent cultures for initial compound assessment, organ culture should find use when the list of compounds to be evaluated is small and when simpler models have narrowed the dose range. Organ-cultured skin also provides a platform for mechanistic studies. PMID:26989431

  6. In Vivo Efficacy of Anuran Trypsin Inhibitory Peptides against Staphylococcal Skin Infection and the Impact of Peptide Cyclization

    PubMed Central

    Malik, U.; Silva, O. N.; Fensterseifer, I. C. M.; Chan, L. Y.; Clark, R. J.; Franco, O. L.; Daly, N. L.

    2015-01-01

    Staphylococcus aureus is a virulent pathogen that is responsible for a wide range of superficial and invasive infections. Its resistance to existing antimicrobial drugs is a global problem, and the development of novel antimicrobial agents is crucial. Antimicrobial peptides from natural resources offer potential as new treatments against staphylococcal infections. In the current study, we have examined the antimicrobial properties of peptides isolated from anuran skin secretions and cyclized synthetic analogues of these peptides. The structures of the peptides were elucidated by nuclear magnetic resonance (NMR) spectroscopy, revealing high structural and sequence similarity with each other and with sunflower trypsin inhibitor 1 (SFTI-1). SFTI-1 is an ultrastable cyclic peptide isolated from sunflower seeds that has subnanomolar trypsin inhibitory activity, and this scaffold offers pharmaceutically relevant characteristics. The five anuran peptides were nonhemolytic and noncytotoxic and had trypsin inhibitory activities similar to that of SFTI-1. They demonstrated weak in vitro inhibitory activities against S. aureus, but several had strong antibacterial activities against S. aureus in an in vivo murine wound infection model. pYR, an immunomodulatory peptide from Rana sevosa, was the most potent, with complete bacterial clearance at 3 mg · kg−1. Cyclization of the peptides improved their stability but was associated with a concomitant decrease in antimicrobial activity. In summary, these anuran peptides are promising as novel therapeutic agents for treating infections from a clinically resistant pathogen. PMID:25624332

  7. Norfloxacin-loaded collagen/chitosan scaffolds for skin reconstruction: Preparation, evaluation and in-vivo wound healing assessment.

    PubMed

    Mahmoud, Azza A; Salama, Alaa H

    2016-02-15

    Biomaterial scaffolds are versatile tools as drug carrier for treatment of wounds. A series of norfloxacin-loaded scaffolds were synthesized for treatment of wounds by combining collagen with two different types of chitosan using freeze-drying technique. Subsequently, scaffolds were screened in terms of morphology, water absorption and retention capacity, biodegradation, ex-vivo bioadhesive strength, in-vitro drug release biological compatibility, X-ray diffractometry, differential scanning calorimetry as well as in-vivo evaluation. The results indicate that the scaffold mechanical strength is dependent on the type of used chitosan. The prepared scaffolds contained interconnected porous architecture. The scaffolds had high water uptake and retention capacity with extended biodegradation rate. Scaffolds prepared with chitosan HCl showed superior bioadhesive strength compared to those prepared with low molecular weight chitosan. All scaffolds showed almost 100% drug release within 24h. As identified by the terahertz pulsed imaging measurements, there is single scaffold area with the same concentration. After 28 days of wound dressing with selected norfoloxacin-loaded or unloaded collagen/chitosan scaffolds in Albino rats, it was found that the tissue regeneration time was fast compared to non-treated wounds. Furthermore, the drug-loaded scaffolds showed normal structure of an intact epidermal layer as well as the underlying dermis as revealed by histopathological studies. The obtained results suggest that the investigated norfloxacin-loaded collagen/chitosan scaffold is a potential candidate for skin regeneration application.

  8. Clinical coherent anti-Stokes Raman scattering and multiphoton tomography of human skin with a femtosecond laser and photonic crystal fiber

    NASA Astrophysics Data System (ADS)

    Breunig, Hans Georg; Weinigel, Martin; Bückle, Rainer; Kellner-Höfer, Marcel; Lademann, Jürgen; Darvin, Maxim E.; Sterry, Wolfram; König, Karsten

    2013-02-01

    We report on in vivo coherent anti-Stokes Raman scattering spectroscopy (CARS), two-photon fluorescence and second-harmonic-generation imaging on human skin with a novel multimodal clinical CARS/multiphoton tomograph. CARS imaging is realized by a combination of femtosecond pulses with broadband continuum pulses generated by a photonic crystal fiber. The images reveal the microscopic distribution of (i) non-fluorescent lipids, (ii) endogenous fluorophores and (iii) the collagen network inside the human skin in vivo with subcellular resolution. Examples of healthy as well as cancer-affected skin are presented.

  9. Structure and function of the human skin microbiome.

    PubMed

    Schommer, Nina N; Gallo, Richard L

    2013-12-01

    An abundant and diverse collection of bacteria, fungi, and viruses inhabits the human skin. These microorganisms vary between individuals and between different sites on the skin. The factors responsible for the unique variability of the skin microbiome are only partly understood, but results suggest that host genetic and environmental influences play a major role. Today, the steady accumulation of data describing the skin microbiome, combined with experiments designed to test the biological functions of surface microbes, has provided new insights into links between human physiology and skin microbiota. This review describes some of the current information regarding the skin microbiome and its impact on human health. Specifically, we summarize the present understanding of the function of microbe-host interactions on the skin and highlight some unique features that distinguish skin commensal organisms from pathogenic microbes.

  10. Structure and function of the human skin microbiome

    PubMed Central

    Schommer, Nina N.; Gallo, Richard L.

    2016-01-01

    An abundant and diverse collection of bacteria, fungi and viruses inhabit the human skin. These microorganisms have been reported to vary between individuals and between different sites on the skin. The factors responsible for the unique variability of the skin microbiome are only partially understood, but results suggest host genetic and environmental influences play a major role. Today, the steady accumulation of data describing the skin microbiome, combined with experiments designed to test the biological functions of surface microbes, have provided new insights into links between human physiology and skin microbiota. This review describes some of the current information regarding the skin microbiome and their impact on human health. Specifically, this review seeks to summarize the present understanding of the function of microbe–host interactions on the skin and highlight some unique features that distinguish skin commensals from pathogenic microbes. PMID:24238601

  11. Role of human skin in the photodecomposition of bilirubin

    PubMed Central

    Kapoor, Chiranjiv L.; Murti, Coimbatore R. Krishna; Bajpai, Prakash C.

    1974-01-01

    1. Human skin epithelium and human skin were found to absorb both free bilirubin and serum-bound bilirubin from an aqueous buffered medium. The serum-bound bilirubin thus absorbed was readily released when human skin epithelium or human skin were transferred to media containing no bilirubin. 2. The Km values for serum-bound bilirubin were 1.8×10−3m and 2.2×10−3m respectively for human skin epithelium and human skin; corresponding Km values for free bilirubin were 3.0×10−4m and 5×10−4m. The Vmax. for bound and free bilirubin was of the same magnitude, the apparent Vmax. being 1.0 and 1.66μmol/g of tissue for human skin epithelium and human skin respectively. 3. When human skin that had acquired a yellow tinge by absorbing bilirubin was incubated in a buffered medium and exposed to a mercury-vapour light, the yellow colour disappeared and decomposition products of bilirubin accumulated in the medium. 4. Experiments with [3H]bilirubin indicated that the pigment absorbed by skin was photo-oxidized to products that were soluble in water and the quantity and number of such products increased with the time of exposure of human skin to the light-source. Under similar conditions [3H]bilirubin alone in buffered medium was also oxidized and gave products which by paper chromatography appeared to be different from those released by human skin that had absorbed bilirubin. 5. The results suggest that by virtue of its large surface area human skin can act as a matrix for the degradative action of light on bilirubin. PMID:4464841

  12. An in vivo model of human small intestine using pluripotent stem cells.

    PubMed

    Watson, Carey L; Mahe, Maxime M; Múnera, Jorge; Howell, Jonathan C; Sundaram, Nambirajan; Poling, Holly M; Schweitzer, Jamie I; Vallance, Jefferson E; Mayhew, Christopher N; Sun, Ying; Grabowski, Gregory; Finkbeiner, Stacy R; Spence, Jason R; Shroyer, Noah F; Wells, James M; Helmrath, Michael A

    2014-11-01

    Differentiation of human pluripotent stem cells (hPSCs) into organ-specific subtypes offers an exciting avenue for the study of embryonic development and disease processes, for pharmacologic studies and as a potential resource for therapeutic transplant. To date, limited in vivo models exist for human intestine, all of which are dependent upon primary epithelial cultures or digested tissue from surgical biopsies that include mesenchymal cells transplanted on biodegradable scaffolds. Here, we generated human intestinal organoids (HIOs) produced in vitro from human embryonic stem cells (ESCs) or induced pluripotent stem cells (iPSCs) that can engraft in vivo. These HIOs form mature human intestinal epithelium with intestinal stem cells contributing to the crypt-villus architecture and a laminated human mesenchyme, both supported by mouse vasculature ingrowth. In vivo transplantation resulted in marked expansion and maturation of the epithelium and mesenchyme, as demonstrated by differentiated intestinal cell lineages (enterocytes, goblet cells, Paneth cells, tuft cells and enteroendocrine cells), presence of functional brush-border enzymes (lactase, sucrase-isomaltase and dipeptidyl peptidase 4) and visible subepithelial and smooth muscle layers when compared with HIOs in vitro. Transplanted intestinal tissues demonstrated digestive functions as shown by permeability and peptide uptake studies. Furthermore, transplanted HIO-derived tissue was responsive to systemic signals from the host mouse following ileocecal resection, suggesting a role for circulating factors in the intestinal adaptive response. This model of the human small intestine may pave the way for studies of intestinal physiology, disease and translational studies.

  13. Electromechanical method coupling non-invasive skin impedance probing and in vivo subcutaneous liquid microinjection: controlling the diffusion pattern of nanoparticles within living soft tissues.

    PubMed

    Sung, Baeckkyoung; Kim, Se Hoon; Lee, Jin-Kyu; Lee, Byung-Cheon; Soh, Kwang-Sup

    2014-08-01

    Transdermal drug delivery is the way to transport drug carriers, such as nanoparticles, across the skin barrier to the dermal and/or subcutaneous layer. In order to control the transdermal drug delivery process, based on the heterogeneous and nonlinear structures of the skin tissues, we developed a novel electromechanical method combining in vivo local skin impedance probing, subcutaneous micro-injection of colloidal nanoparticles, and transcutaneous electrical stimulation. Experiments on the nude mice using in vivo fluorescence imaging exhibited significantly different apparent diffusion patterns of the nanoparticles depending on the skin impedance: Anisotropic and isotropic patterns were observed upon injection into low and high impedance points, respectively. This result implies that the physical complexity in living tissues may cause anisotropic diffusion of drug carriers, and can be used as a parameter for controlling drug delivery process. This method also can be combined with microneedle-based drug release systems, micro-fabricated needle-electrodes, and/or advanced in vivo targeting/imaging technologies using nanoparticles.

  14. In-Vivo Time Domain Measurement of Dielectric Properties of Human Body Tissue

    NASA Astrophysics Data System (ADS)

    Koyama, Kazunori; Hirata, Akimasa; Wang, Jianquing; Fujiwara, Osamu

    It is essential to measure dielectric properties of human tissues for the safety evaluation of electromagnetic field exposures. In this paper, towards developing an in-vivo measurement method for living human tissues, we employed an open-ended coaxial probe together with a time domain reflectometry (TDR) technique, which probably enables us to extract a reflected waveform from some specified tissues in the time domain. We compared the TDR-measured dielectric properties for human surface tissues with those derived from a conventional frequency-domain technique. As a result, we found a fair agreement between them in the frequency range from 300 MHz to 6 GHz. This result suggests the possibility of in-vivo dielectric property measurement for superficial human tissues by using the proposed TDR technique.

  15. In vitro antioxidant and in vivo photoprotective effect of pistachio (Pistacia vera L., variety Bronte) seed and skin extracts.

    PubMed

    Martorana, Maria; Arcoraci, Teresita; Rizza, Luisa; Cristani, Mariateresa; Bonina, Francesco Paolo; Saija, Antonina; Trombetta, Domenico; Tomaino, Antonio

    2013-03-01

    Pistachio (Pistacia vera L.) nuts are a rich source of phenolic compounds, known for their high antioxidant activity, and contained not only in the seeds but also in the skin. A pistachio cultivar of high quality is typical of Bronte, Sicily, Italy. The purpose of our study was to investigate the chemical composition and antioxidant properties of two polyphenol-rich extracts from skins (TP) and decorticated seeds (SP) of Bronte pistachios, and to verify the potential use of these extracts for topical photoprotective products. Chemical analysis showed that the TP and SP extracts contain high levels of phenolic compounds, but the TP extract is about ten times richer in phenols than the SP extract, being anthocyanins the most abundant compounds found in the TP extract. Both these extracts, and especially the TP extract, possess good radical scavenger/antioxidant properties, as shown in a series of in vitro assays carried out using homogenous and non-homogenous chemical environment. Furthermore both the TP extract and, although at a lower degree, the SP extract reduce, when topically applied, UV-B-induced skin erythema in human volunteers. These findings suggest that extracts from Bronte TP and SP could be successfully employed as photoprotective ingredients in topical cosmetic and pharmaceutical formulations.

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

    NASA Astrophysics Data System (ADS)

    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.

  17. Vascular endothelial growth factor is a potential tumour angiogenesis factor in human gliomas in vivo

    NASA Astrophysics Data System (ADS)

    Plate, Karl H.; Breier, Georg; Weich, Herbert A.; Risau, Werner

    1992-10-01

    CLINICAL and experimental studies suggest that angiogenesis is a prerequisite for solid tumour growth1,2. Several growth factors with mitogenic or chemotactic activity for endothelial cells in vitro have been described, but it is not known whether these mediate tumour vascularization in vivo3,4. Glioblastoma, the most common and most malignant brain tumour in humans, is distinguished from astrocytoma by the presence of necroses and vascular prolifer-ations5'6. Here we show that expression of an endothelial cell-specific mitogen, vascular endothelial growth factor (VEGF), is induced in astrocytoma cells but is dramatically upregulated in two apparently different subsets of glioblastoma cells. The high-affinity tyrosine kinase receptor for VEGF, flt, although not expressed in normal brain endothelium, is upregulated in tumour endothelial cells in vivo. These observations strongly support the concept that tumour angiogenesis is regulated by paracrine mechanisms and identify VEGF as a potential tumour angiogenesis factor in vivo.

  18. In vivo measurement of mechanical properties of human long bone by using sonic sound

    NASA Astrophysics Data System (ADS)

    Hossain, M. Jayed; Rahman, M. Moshiur; Alam, Morshed

    2016-07-01

    Vibration analysis has evaluated as non-invasive techniques for the in vivo assessment of bone mechanical properties. The relation between the resonant frequencies, long bone geometry and mechanical properties can be obtained by vibration analysis. In vivo measurements were performed on human ulna as a simple beam model with an experimental technique and associated apparatus. The resonant frequency of the ulna was obtained by Fast Fourier Transformation (FFT) analysis of the vibration response of piezoelectric accelerometer. Both elastic modulus and speed of the sound were inferred from the resonant frequency. Measurement error in the improved experimental setup was comparable with the previous work. The in vivo determination of bone elastic response has potential value in screening programs for metabolic bone disease, early detection of osteoporosis and evaluation of skeletal effects of various therapeutic modalities.

  19. Engineering human cells for in vivo secretion of antibody and non-antibody therapeutic proteins.

    PubMed

    Sánchez-Martín, David; Sanz, Laura; Álvarez-Vallina, Luis

    2011-12-01

    Purified proteins such as antibodies are widely used as therapeutic agents in clinical medicine. However, clinical-grade proteins for therapeutic use require sophisticated technologies and are extremely expensive to produce. In vivo secretion of therapeutic proteins by genetically engineered human cells may advantageously replace injection of highly purified proteins. The use of gene transfer methods circumvents problems related to large-scale production and purification and offers additional benefits by achieving sustained concentrations of therapeutic protein with a syngenic glycosylation pattern that make the protein potentially less immunogenic. The feasibility of the in vivo production of therapeutic proteins by diverse cells/tissues has now been demonstrated using different techniques, such as ex vivo genetically modified cells and in vivo gene transfer mediated by viral vectors.

  20. Applications of stable, nonradioactive isotope tracers in in vivo human metabolic research

    PubMed Central

    Kim, Il-Young; Suh, Sang-Hoon; Lee, In-Kyu; Wolfe, Robert R

    2016-01-01

    The human body is in a constant state of turnover, that is, being synthesized, broken down and/or converted to different compounds. The dynamic nature of in vivo kinetics of human metabolism at rest and in stressed conditions such as exercise and pathophysiological conditions such as diabetes and cancer can be quantitatively assessed with stable, nonradioactive isotope tracers in conjunction with gas or liquid chromatography mass spectrometry and modeling. Although measurements of metabolite concentrations have been useful as general indicators of one's health status, critical information on in vivo kinetics of metabolites such as rates of production, appearance or disappearance of metabolites are not provided. Over the past decades, stable, nonradioactive isotope tracers have been used to provide information on dynamics of specific metabolites. Stable isotope tracers can be used in conjunction with molecular and cellular biology tools, thereby providing an in-depth dynamic assessment of metabolic changes, as well as simultaneous investigation of the molecular basis for the observed kinetic responses. In this review, we will introduce basic principles of stable isotope methodology for tracing in vivo kinetics of human or animal metabolism with examples of quantifying certain aspects of in vivo kinetics of carbohydrate, lipid and protein metabolism. PMID:26795236