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Sample records for abnormal skin pigmentation

  1. Skin Pigmentation Disorders

    MedlinePlus

    Pigmentation means coloring. Skin pigmentation disorders affect the color of your skin. Your skin gets its color from a pigment called melanin. Special cells in the skin make melanin. When these cells become damaged or ...

  2. Skin Pigment

    MedlinePlus

    ... Diseases Take Big Slice Out of America's Health, Economy (News) Health Tip: Use Caution When Applying Hair Dye Additional ... Skin Diseases Take Big Slice Out of America's Health, Economy THURSDAY, March 2, 2017 (HealthDay News) -- Skin diseases ...

  3. Chlorpromazine-induced skin pigmentation with corneal and lens opacities.

    PubMed

    Huff, Laura S; Prado, Renata; Pederson, Jon F; Dunnick, Cory A; Lucas, Lisa M

    2014-05-01

    Chlorpromazine is known to cause abnormal oculocutaneous pigmentation in sun-exposed areas. We present the case of a psychiatric patient who developed blue-gray pigmentation of the skin as well as corneal and lens opacities following 7 years of chlorpromazine treatment. Ten months after discontinuation of chlorpromazine, the skin discoloration and anterior lens deposits showed partial improvement, but the corneal deposits remained unchanged. A review of the literature on the reversibility of chlorpromazine-induced abnormal oculocutaneous pigmentation also is provided.

  4. Dermoscopy of pigmented skin lesions.

    PubMed

    Soyer, H P; Argenziano, G; Chimenti, S; Ruocco, V

    2001-01-01

    This paper describes the basic concepts of dermoscopy, the various dermoscopic equipments and the standard criteria for diagnosing pigmented skin lesions. In assessing dermoscopic images, both global and local features can be recognized. These features will be systematically described and illustrated in Part I of this article. First, we will focus on 8 morphologically rather distinctive global features that allow a quick, preliminary categorization of a given pigmented skin lesion. Second, we will describe various local features representing the letters of the dermoscopic alphabet. The local features permit a more detailed assessment of pigmented skin lesions.

  5. Abnormal pigmentation within cutaneous scars: A complication of wound healing

    PubMed Central

    Chadwick, Sarah; Heath, Rebecca; Shah, Mamta

    2012-01-01

    Abnormally pigmented scars are an undesirable consequence of cutaneous wound healing and are a complication every single individual worldwide is at risk of. They present a challenge for clinicians, as there are currently no definitive treatment options available, and render scars much more noticeable making them highly distressing for patients. Despite extensive research into both wound healing and the pigment cell, there remains a scarcity of knowledge surrounding the repigmentation of cutaneous scars. Pigment production is complex and under the control of many extrinsic and intrinsic factors and patterns of scar repigmentation are unpredictable. This article gives an overview of human skin pigmentation, repigmentation following wounding and current treatment options. PMID:23162241

  6. Continuous illumination through larval development suppresses dopamine synthesis in the suprachiasmatic nucleus, causing activation of α-MSH synthesis in the pituitary and abnormal metamorphic skin pigmentation in flounder.

    PubMed

    Itoh, Kae; Washio, Youhei; Fujinami, Yuichiro; Shimizu, Daisuke; Uji, Susumu; Yokoi, Hayato; Suzuki, Tohru

    2012-04-01

    In order to better understand the endocrine aberrations related to abnormal metamorphic pigmentation that appear in flounder larvae reared in tanks, this study examined the effects of continuous 24-h illumination (LL) through larval development on the expression of tyrosine hydroxylase-1 (th1), proopiomelanocortin (pomc), α-melanophore-stimulating hormone (α-MSH) and melanin concentrating hormone (MCH), which are known to participate in the control of background adaptation of body color. We observed two conspicuous deviations in the endocrine system under LL when compared with natural light conditions (LD). First, LL severely suppressed th1 expression in the dopaminergic neurons in the anterior diencephalon, including the suprachiasmatic nucleus (SCN). Second, pomc and α-MSH expression in the pars intermedia melanotrophs was enhanced by LL. Skin color was paler under LL than LD before metamorphic pigmentation, and abnormal metamorphic pigmentation occurred at a higher ratio in LL. We therefore hypothesize that continuous LL inhibited dopamine synthesis in the SCN, which resulted in up-regulation of pomc mRNA expression in the melanotrophs. In spite of the up-regulation of pomc in the melanotrophs, larval skin was adjusted to be pale by MCH which was not affected by LL. Accumulation of α-MSH in the melanotrophs is caused by uncoupling of α-MSH synthesis and secretion due to inhibitory role of MCH on α-MSH secretion, which results in abnormal metamorphic pigmentation by affecting differentiation of adult-type melanophores. Our data demonstrate that continuous illumination at the post-embryonic stage has negative effects on the neuroendocrine system and pituitary in flounder.

  7. Challenges of identifying eczema in darkly pigmented skin.

    PubMed

    Myers, Joan

    2015-07-01

    There is a paucity of information about the difference in the presentation of eczema in darkly pigmented skin compared to children with fair or white skin. This article describes the possible challenges of diagnosing eczema in children with darkly pigmented skin. The physiological difference in darkly pigmented skin compared with fair or white skin is explored, and how eczema may be manifested and identified in darkly pigmented skin. The author uses the term darkly pigmented skin to describe children of black Caribbean, African or Asian descent.

  8. Optical tomography of pigmented human skin biopsies

    NASA Astrophysics Data System (ADS)

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

    2004-07-01

    The novel femtosecond NIR (near infrared) laser based high resolution imaging system DermaInspect was used for non-invasive diagnostics of pigmented skin. The system provides fluorescence and SHG images of high spatial submicron resolution (3D) and 250 ps temporal resolution (4D) based on time resolved single photon counting (TCSPC). Pigmented tissue biopsies from patients with nevi and melanoma have been investigated using the tunable 80 MHz femtosecond laser MaiTai with laser wavelengths in the range of 750 - 850 nm. The autofluorescence patterns of different intratissue cell types and structures were determined. The non-linear induced autofluorescence originates from naturally endogenous fluorophores and protein structures like NAD(P)H, flavins, elastin, collagen, phorphyrins and melanin. In addition to autofluorescence, SHG (second harmonic generation) was used to detect dermal collagen structures. Interestingly, pigmented cells showed intense luminescence signals. Further characterization of tissue components was performed via 4D measurements of the fluorescence lifetime (x, y, z, τ). The novel multiphoton technique offers the possibility of a painless high resolution non invasive diagnostic method (optical biopsy), in particular for the early detection of skin cancer.

  9. 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

  10. Mutant laboratory mice with abnormalities in pigmentation: annotated tables.

    PubMed

    Nakamura, Motonobu; Tobin, Desmond J; Richards-Smith, Beverly; Sundberg, John P; Paus, Ralf

    2002-01-01

    Mammalian pigment cell research has recently entered a phase of significantly increased activity due largely to the exploitation of the many mutant mouse stocks that are coming on stream. Numerous transgenic, targeted mutagenesis (so-called 'knockouts'), conditional (so-called 'gene switch') and spontaneous mutant mice develop abnormal coat color phenotypes. The number of mice that exhibit such abnormalities is increasing exponentially as genetic engineering methods become routine. Since defined abnormalities in such mutant mice provide important clues to the as yet often poorly understood functional roles of many gene products, this overview includes a corresponding, annotated table of mutant mice with pigmentation alterations. These range from early developmental defects via a large array of coat color abnormalities to a melanoma metastasis model. This overview should provide helpful pointers to investigators who are looking for mouse models to explore or to compare functional activities of genes of interest and for comparing coat color phenotypes of spontaneous or genetically engineered mouse mutants with novel ones. Secondly, this review includes a table of mouse models of specific human diseases with genetically defined pigmentation abnormalities. In summary, this annotated table should serve as a useful reference for anyone interested in the molecular controls of pigmentation.

  11. Skin - abnormally dark or light

    MedlinePlus

    ... Endocrine diseases such as Addison disease Hemochromatosis (iron overload) Sun exposure Pregnancy Causes of hypopigmentation include: Skin ... to achieve this important distinction for online health information and services. Learn more about A.D.A. ...

  12. Mechanisms Regulating Skin Pigmentation: The Rise and Fall of Complexion Coloration

    PubMed Central

    Ebanks, Jody P.; Wickett, R. Randall; Boissy, Raymond E.

    2009-01-01

    Skin pigmentary abnormalities are seen as aesthetically unfavorable and have led to the development of cosmetic and therapeutic treatment modalities of varying efficacy. Hence, several putative depigmenting agents aimed at modulating skin pigmentation are currently being researched or sold in commercially available products. In this review we will discuss the regulation of processes that control skin complexion coloration. This includes direct inhibition of tyrosinase and related melanogenic enzymes, regulation of melanocyte homeostasis, alteration of constitutive and facultative pigmentation and down-regulation of melanosome transfer to the keratinocytes. These various processes, in the complex mechanism of skin pigmentation, can be regulated individually or concomitantly to alter complexion coloration and thus ameliorate skin complexion diseases. PMID:19865532

  13. BASIS FOR ENHANCED BARRIER FUNCTION OF PIGMENTED SKIN

    PubMed Central

    Man, Mao-Qiang; Lin, Tzu-Kai; Santiago, Juan Luis; Celli, Anna; Zhong, Lily; Huang, Zhi-Ming; Roelandt, Truus; Hupe, Melanie; Sundberg, John P.; Silva, Kathleen A.; Crumrine, Debra; Martin-Ezquerra, Gemma; Trullas, Carles; Sun, Richard; Wakefield, Joan S.; Wei, Maria L.; Feingold, Kenneth R.; Mauro, Theodora M.; Elias, Peter M.

    2014-01-01

    Humans with darkly-pigmented skin display superior permeability barrier function in comparison to humans with lightly-pigmented skin. The reduced pH of the stratum corneum (SC) of darkly-pigmented skin could account for enhanced function, because acidifying lightly-pigmented human SC resets barrier function to darkly-pigmented levels. In SKH1 (non-pigmented) vs. SKH2/J (pigmented) hairless mice, we evaluated how a pigment-dependent reduction in pH could influence epidermal barrier function. Permeability barrier homeostasis is enhanced in SKH2/J vs. SKH1 mice, correlating with a reduced pH in the lower SC that co-localizes with the extrusion of melanin granules. Darkly-pigmented human epidermis also shows substantial melanin extrusion in the outer epidermis. Both acute barrier disruption and topical basic pH challenges accelerate re-acidification of SKH2/J (but not SKH1) SC, while inducing melanin extrusion. SKH2/J mice also display enhanced expression of the SC acidifying enzyme, secretory phospholipase A2f (sPLA2f). Enhanced barrier function of SKH2/J mice could be attributed to enhanced activity of two acidic pH-dependent, ceramide-generating enzymes, β-glucocerebrosidase and acidic sphingomyelinase, leading to accelerated maturation of SC lamellar bilayers. Finally, organotypic cultures of darkly-pigmented-bearing human keratinocytes display enhanced barrier function in comparison to lightly-pigmented cultures. Together, these results suggest that the superior barrier function of pigmented epidermis can be largely attributed to the pH-lowering impact of melanin persistence/extrusion and enhanced sPLA2f expression. PMID:24732399

  14. A life history perspective on skin cancer and the evolution of skin pigmentation.

    PubMed

    Osborne, Daniel L; Hames, Raymond

    2014-01-01

    The ancestral state of human skin pigmentation evolved in response to high ultraviolet radiation (UVR) stress. Some argue that pigmentation evolved to limit folate photolysis, therein limiting neural tube defects. Pigmentation also protects against sunburn which decreases the efficiency of sweating and potentiates skin infection. Pigmentation increases the efficacy of skin as a barrier to infection. Skin cancer has been rejected or minimized as a selective pressure because it is believed to have little or no effect on mortality during reproductive years. This argument ignores evidence of human longevity as a derived life history trait and the adaptive value of investment in offspring and kin, particularly during the post-reproductive lifespan. Opponents argue that lifespan in prehistoric hunter-gatherers was too short to be relevant to the evolution of skin pigmentation. This argument is flawed in that it relies on estimates of longevity at birth rather than adolescence. When appropriate estimates are used, it is clear that human longevity has a deep evolutionary history. We use a life history perspective to demonstrate the value of skin pigmentation as an adaptation to skin cancer with the following points: UVR exposure increases dysregulation of gene expression in skin cells leading to immortal cell lines; cutaneous malignant melanoma (CMM) affects individuals throughout reproductive years; and lifespan was longer than has previously been acknowledged, providing the opportunity for kin selection. This hypothesis is not at odds with the folate or barrier hypotheses. We stress that the evolution of skin pigmentation is complex and is an ongoing process.

  15. Human skin pigmentation as an adaptation to UV radiation

    PubMed Central

    Jablonski, Nina G.; Chaplin, George

    2010-01-01

    Human skin pigmentation is the product of two clines produced by natural selection to adjust levels of constitutive pigmentation to levels of UV radiation (UVR). One cline was generated by high UVR near the equator and led to the evolution of dark, photoprotective, eumelanin-rich pigmentation. The other was produced by the requirement for UVB photons to sustain cutaneous photosynthesis of vitamin D3 in low-UVB environments, and resulted in the evolution of depigmented skin. As hominins dispersed outside of the tropics, they experienced different intensities and seasonal mixtures of UVA and UVB. Extreme UVA throughout the year and two equinoctial peaks of UVB prevail within the tropics. Under these conditions, the primary selective pressure was to protect folate by maintaining dark pigmentation. Photolysis of folate and its main serum form of 5-methylhydrofolate is caused by UVR and by reactive oxygen species generated by UVA. Competition for folate between the needs for cell division, DNA repair, and melanogenesis is severe under stressful, high-UVR conditions and is exacerbated by dietary insufficiency. Outside of tropical latitudes, UVB levels are generally low and peak only once during the year. The populations exhibiting maximally depigmented skin are those inhabiting environments with the lowest annual and summer peak levels of UVB. Development of facultative pigmentation (tanning) was important to populations settling between roughly 23° and 46° , where levels of UVB varied strongly according to season. Depigmented and tannable skin evolved numerous times in hominin evolution via independent genetic pathways under positive selection. PMID:20445093

  16. Modifying skin pigmentation – approaches through intrinsic biochemistry and exogenous agents

    PubMed Central

    Brenner, Michaela; Hearing, Vincent J.

    2008-01-01

    Rates of skin cancer continue to increase despite the improved use of traditional sunscreens to minimize damage from ultraviolet radiation. The public perception of tanned skin as being healthy and desirable, combined with the rising demand for treatments to repair irregular skin pigmentation and the desire to increase or decrease constitutive skin pigmentation, arouses great interest pharmaceutically as well as cosmeceutically. This review discusses the intrinsic biochemistry of pigmentation, details mechanisms that lead to increased or decreased skin pigmentation, and summarizes established and potential hyper- and hypo-pigmenting agents and their modes of action. PMID:19578486

  17. Skin as a living coloring book: how epithelial cells create patterns of pigmentation.

    PubMed

    Weiner, Lorin; Fu, Wenyu; Chirico, William J; Brissette, Janice L

    2014-11-01

    The pigmentation of mammalian skin and hair develops through the interaction of two basic cell types - pigment donors and recipients. The pigment donors are melanocytes, which produce and distribute melanin through specialized structures. The pigment recipients are epithelial cells, which acquire melanin and put it to use, collectively yielding the pigmentation visible to the eye. This review will focus on the pigment recipients, the historically less understood cell type. These end-users of pigment are now known to exert a specialized control over the patterning of pigmentation, as they identify themselves as melanocyte targets, recruit pigment donors, and stimulate the transfer of melanin. As such, this review will discuss the evidence that the skin is like a coloring book: the pigment recipients create a 'picture,' a blueprint for pigmentation, which is colorless initially but outlines where pigment should be placed. Melanocytes then melanize the recipients and 'color in' the picture.

  18. Effects of palmitoyl-KVK-L-ascorbic acid on skin wrinkles and pigmentation.

    PubMed

    Kim, Hyeong Mi; An, Hyo Sun; Bae, Jung-Soo; Kim, Jung Yun; Choi, Chi Ho; Kim, Ju Yeon; Lim, Joo Hyuck; Choi, Joon-Hun; Song, Hyunnam; Moon, Sung Ho; Park, Young Jun; Chang, Shin-Jae; Choi, Sun Young

    2017-03-16

    Wrinkle formation and abnormal pigmentation are major clinical alterations associated with skin aging. As the aim of our study was to investigate the effects of palmitoyl-KVK-L-ascorbic acid on skin aging, the anti-wrinkle and depigmentation effects of palmitoyl-KVK-L-ascorbic acid were evaluated by measuring collagen expression in dermal fibroblast cells and inhibition of melanogenesis in B16F1 cells, respectively. The anti-aging effect of palmitoyl-KVK-L-ascorbic acid cream was also evaluated against a placebo cream in a clinical trial. Our results confirmed that the expression of type Ι collagen in dermal fibroblast cells treated with palmitoyl-KVK-L-ascorbic acid (0.1-4 μg/mL) increased in a dose-dependent manner. In B16F1 cells, treatment with 20 μg/mL palmitoyl-KVK-L-ascorbic acid reduced the melanin content by approximately 20% compared to alpha-melanocyte stimulating hormone treatment. In the clinical trial, application of palmitoyl-KVK-L-ascorbic acid cream led to an improvement in skin roughness and lightness in 12 and 8 weeks, respectively. Our data show that palmitoyl-KVK-L-ascorbic acid is an effective anti-aging agent that reduces wrinkles and abnormal skin pigmentation.

  19. Optothermal skin pigment spectral depth profiling using an OPO laser

    NASA Astrophysics Data System (ADS)

    Xiao, Peng; Guo, Xinxin; Notingher, Ioan; Cowen, Anna J.; O'Driscoll, Don; Imhof, Robert E.

    1999-06-01

    This paper presents the results of a research program to quantify the factors that determine the visual appearance of human skin. We use in-vivo opto-thermal transient emission radiometry (OTTER) with a tunable OPO laser (400 - 590 nm) to measure spectrally resolved pigment depth profiles. Radiation in this wavelength range is only weakly absorbed by stratum corneum and epidermis, but strongly absorbed by sub-surface pigments, mainly melanin and haemoglobin. These produce characteristic delayed thermal wave (DTW) signals, detected using a high speed Mercury Cadmium Telluride detector sensitive in the wavelength range 6 - 13 microns. The measured intensity-time profiles yield the desired concentration depth profiles through either model-based non-linear least-squares analysis or model-independent inverse analysis. Results on melanin and haemoglobin distributions within normal, tape stripped and wash-damaged skin are presented.

  20. The Effect of Skin Pigmentation on the Accuracy of Pulse Oximetry in Infants with Hypoxemia.

    PubMed

    Foglia, Elizabeth E; Whyte, Robin K; Chaudhary, Aasma; Mott, Antonio; Chen, Jodi; Propert, Kathleen J; Schmidt, Barbara

    2017-03-01

    To compare pulse oximetry measurement bias between infants with hypoxemia with either dark skin or light skin with Masimo Radical 7 and Nellcor Oximax. There was no significant difference in systematic bias based on skin pigment for either oximeter.

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

    PubMed

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

    2013-06-01

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

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

    PubMed

    Ortonne, J-P

    2009-10-01

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

  3. Multiple-reflection model of human skin and estimation of pigment concentrations

    NASA Astrophysics Data System (ADS)

    Ohtsuki, Rie; Tominaga, Shoji; Tanno, Osamu

    2012-07-01

    We describe a new method for estimating the concentrations of pigments in the human skin using surface spectral reflectance. We derive an equation that expresses the surface spectral reflectance of the human skin. First, we propose an optical model of the human skin that accounts for the stratum corneum. We also consider the difference between the scattering coefficient of the epidermis and that of the dermis. We then derive an equation by applying the Kubelka-Munk theory to an optical model of the human skin. Unlike a model developed in a recent study, the present equation considers pigments as well as multiple reflections and the thicknesses of the skin layers as factors that affect the color of the human skin. In two experiments, we estimate the pigment concentrations using the measured surface spectral reflectances. Finally, we confirm the feasibility of the concentrations estimated by the proposed method by evaluating the estimated pigment concentrations in the skin.

  4. Skin pigmentation and texture changes after hair removal with the normal-mode ruby laser.

    PubMed

    Haedersdal, M; Egekvist, H; Efsen, J; Bjerring, P

    1999-11-01

    Promising clinical results have been obtained with the normal mode ruby laser for removal of unwanted hair. Melanin within the hair follicles is thought to act as target for the ruby laser pulses, whereas epidermal melanin is thought to be a competitive chromophore, responsible for potential side effects. This study aimed (i) to objectify postoperative changes in skin pigmentation and texture and (ii) to evaluate the importance of variations in preoperative skin pigmentation for the development of side effects 12 weeks after 1 treatment with the normal-mode ruby laser. A total of 17 volunteers (skin types I-IV) were laser-treated in the hairy pubic region (n = 51 test areas). A shaved test area served as control. Skin reflectance spectroscopical measurements, 3-dimensional surface contour analysis and ultrasonography objectified postoperative changes in skin pigmentation and texture. Blinded clinical assessments revealed postoperative hyperpigmentation (2% of test areas) and hypopigmentation (10%), whereas no textural changes were seen. Reflectance spectroscopically-determined pigmentary changes depended on the degree of preoperative skin pigmentation, fairly pigmented skin types experiencing subclinical hyperpigmentation and darkly pigmented skin types experiencing subclinical hypopigmentation. Three-dimensional surface profilometry documented similar pre- and postoperative surface contour parameters, indicating that the skin surface texture is preserved after laser exposure. Ultrasonography revealed similar skin thicknesses in laser-exposed and untreated control areas. It is concluded that normal-mode ruby laser treatment is safe for hair removal in skin types I-IV.

  5. Is the skin barrier abnormal in dogs with atopic dermatitis?

    PubMed

    Olivry, Thierry

    2011-11-15

    In mammalian skin, the stratum corneum exerts a barrier function that protects from transepidermal water loss and the penetration of exogenous molecules, such as allergens, from the environment. Recently, skin barrier defects have been shown to be of prime importance in the pathogenesis of human atopic dermatitis. In this review, we summarize the latest research data pertinent to the stratum corneum and barrier function of dogs with atopic dermatitis. At the time of this writing, there is increasing evidence that a skin barrier defect likely exists in dogs with atopic dermatitis. This barrier dysfunction is characterized by abnormal intercellular stratum corneum lipid lamellae, abnormal stratum corneum morphology, reduced and abnormal ceramide content and, in some but not all dogs, abnormal filaggrin expression. In association with these changes, there is higher transepidermal water loss in atopic than in normal canine skin. Furthermore, atopic inflammation appears to worsen transepidermal water loss and filaggrin expression. It remains unknown, however, if the changes observed are primary (i.e. of genetic origin) or secondary to atopic inflammation that also exists even in clinically normal skin. Finally, whether or not a therapeutic intervention aimed at restoring a dysfunctional skin barrier is of any clinical benefit to atopic dogs has not yet been proven unequivocally.

  6. Shining light on skin pigmentation: the darker and the brighter side of effects of UV radiation.

    PubMed

    Maddodi, Nityanand; Jayanthy, Ashika; Setaluri, Vijayasaradhi

    2012-01-01

    The term barrier function as applied to human skin often connotes the physical properties of this organ that provides protection from its surrounding environment. This term does not generally include skin pigmentation. However, skin pigmentation, which is the result of melanin produced in melanocytes residing in the basal layer of the skin and exported to the keratinocytes in the upper layers, serves equally important protective function. Indeed, changes in skin pigmentation are often the most readily recognized indicators of exposure of skin to damaging agents, especially to natural and artificial radiation in the environment. Several recent studies have shed new light on (1) the mechanisms involved in selective effects of subcomponents of UV radiation on human skin pigmentation and (2) the interactive influences between keratinocytes and melanocytes, acting as "epidermal melanin unit," that manifest as changes in skin pigmentation in response to exposure to various forms of radiation. This article provides a concise review of our current understanding of the effects of the nonionizing solar radiation, at cellular and molecular levels, on human skin pigmentation.

  7. Skin Pigmentation and Pigmentary Disorders: Focus on Epidermal/Dermal Cross-Talk

    PubMed Central

    Bastonini, Emanuela; Kovacs, Daniela

    2016-01-01

    Variation in human skin and hair color is the most notable aspect of human variability and several studies in evolution, genetics and developmental biology contributed to explain the mechanisms underlying human skin pigmentation, which is responsible for differences in skin color across the world's populations. Despite skin pigmentation is primarily related to melanocytes functionality, the surrounding keratinocytes and extracellular matrix proteins and fibroblasts in the underlying dermal compartment actively contribute to cutaneous homeostasis. Many autocrine/paracrine secreted factors and cell adhesion mechanisms involving both epidermal and dermal constituents determine constitutive skin pigmentation and, whenever deregulated, the occurrence of pigmentary disorders. In particular, an increased expression of such mediators and their specific receptors frequently lead to hyperpigmentary conditions, such as in melasma and in solar lentigo, whereas a defect in their expression/release is related to hypopigmented disorders, as seen in vitiligo. All these interactions underline the relevant role of pigmentation on human evolution and biology. PMID:27274625

  8. Melanin pigmentation in mammalian skin and its hormonal regulation.

    PubMed

    Slominski, Andrzej; Tobin, Desmond J; Shibahara, Shigeki; Wortsman, Jacobo

    2004-10-01

    Cutaneous melanin pigment plays a critical role in camouflage, mimicry, social communication, and protection against harmful effects of solar radiation. Melanogenesis is under complex regulatory control by multiple agents interacting via pathways activated by receptor-dependent and -independent mechanisms, in hormonal, auto-, para-, or intracrine fashion. Because of the multidirectional nature and heterogeneous character of the melanogenesis modifying agents, its controlling factors are not organized into simple linear sequences, but they interphase instead in a multidimensional network, with extensive functional overlapping with connections arranged both in series and in parallel. The most important positive regulator of melanogenesis is the MC1 receptor with its ligands melanocortins and ACTH, whereas among the negative regulators agouti protein stands out, determining intensity of melanogenesis and also the type of melanin synthesized. Within the context of the skin as a stress organ, melanogenic activity serves as a unique molecular sensor and transducer of noxious signals and as regulator of local homeostasis. In keeping with these multiple roles, melanogenesis is controlled by a highly structured system, active since early embryogenesis and capable of superselective functional regulation that may reach down to the cellular level represented by single melanocytes. Indeed, the significance of melanogenesis extends beyond the mere assignment of a color trait.

  9. Extensive regression in pigmented skin lesions: a dangerous confounding feature

    PubMed Central

    Lallas, Aimilios; Apalla, Zoe; Moscarella, Elvira; Zalaudek, Iris; Tzellos, Thrasivoulos; Lefaki, Ioanna; Cota, Carlo; Argenziano, Giuseppe

    2012-01-01

    Spontaneous regression in melanomas is not an uncommon phenomenon, as it has been described in 10–35% of primary cutaneous lesions [1]. Regression does not appear to predict a more favorable course, since even fully regressed melanomas may progress into metastatic disease [2]. Several dermoscopic features have been correlated with the regression process, including white scar-like depigmented areas and gray-blue, pepper-like granules, which correspond to dermal scarring, pigment incontinence and presence of melanophages [3,4]. Regression may occur not only in melanomas, but also in melanocytic nevi, which similarly may exhibit white areas and gray-blue granules or areas under dermoscopy [5]. Overall, white areas have been proposed to be associated with the fibrosis type of regression and gray-blue areas to the melanosis type of regression of melanocytic tumors [3]. Lichen planus like keratosis (LPLK) is considered to represent a regressed solar lentigo or seborrheic keratosis. Dermoscopy of LPLK at the late stage of the regression process reveals a diffuse gray-blue granular pattern, similar to that observed in regressed melanocytic lesions [6]. In this context, when evaluating skin lesions that exhibit high degree of regression, interpretation of dermoscopic findings may be problematic, especially when no other dermoscopic clues can be recognized. PMID:23785596

  10. Extensive regression in pigmented skin lesions: a dangerous confounding feature.

    PubMed

    Lallas, Aimilios; Apalla, Zoe; Moscarella, Elvira; Zalaudek, Iris; Tzellos, Thrasivoulos; Lefaki, Ioanna; Cota, Carlo; Argenziano, Giuseppe

    2012-04-01

    Spontaneous regression in melanomas is not an uncommon phenomenon, as it has been described in 10-35% of primary cutaneous lesions [1]. Regression does not appear to predict a more favorable course, since even fully regressed melanomas may progress into metastatic disease [2]. Several dermoscopic features have been correlated with the regression process, including white scar-like depigmented areas and gray-blue, pepper-like granules, which correspond to dermal scarring, pigment incontinence and presence of melanophages [3,4]. Regression may occur not only in melanomas, but also in melanocytic nevi, which similarly may exhibit white areas and gray-blue granules or areas under dermoscopy [5]. Overall, white areas have been proposed to be associated with the fibrosis type of regression and gray-blue areas to the melanosis type of regression of melanocytic tumors [3]. Lichen planus like keratosis (LPLK) is considered to represent a regressed solar lentigo or seborrheic keratosis. Dermoscopy of LPLK at the late stage of the regression process reveals a diffuse gray-blue granular pattern, similar to that observed in regressed melanocytic lesions [6]. In this context, when evaluating skin lesions that exhibit high degree of regression, interpretation of dermoscopic findings may be problematic, especially when no other dermoscopic clues can be recognized.

  11. 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.

  12. 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.

  13. Theoretical review of the treatment of pigmented lesions in Asian skin

    PubMed Central

    Shek, Samantha Y.; Chan, Henry H.L.; Groff, William F.; Imagawa, Kotaro; Akamatsu, Tadashi

    2016-01-01

    Asian skin has a higher epidermal melanin content, making it more likely to develop adverse pigmentary reactions following laser surgery. The nanosecond lasers are the gold standard for the treatment of pigmented lesions, but the risk of complications, such as post-inflammatory hyperpigmentation, is increased in dark-skinned patients. Intense Pulsed Light (IPL) or long-pulsed lasers are available for treating superficial pigmented lesions, and fewer complications are seen when using these devices compared to the nanosecond lasers. Nanosecond lasers are essential in the treatment of dermal melanosis. Recently, picosecond lasers have been investigated. Picosecond lasers will also play an important role in the treatment of pigmented lesions. PMID:27853342

  14. 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.

  15. Tracheobronchial cytologic changes and abnormal serum heme pigments in hemorrhagic shock.

    PubMed

    Friedman-Mor, Z; Chalon, J; Turndorf, H; Orkin, L R

    1977-11-01

    Significantly elevated numbers of iron laden histiocytes have been shown to appear in the tracheobronchial secretions of subjects in hemorrhagic shock and in patients undergoing open heart-surgery during cardiopulmonary bypass (3,4). Abnormal heme pigments have also been demonstrated in the serum of dogs bled to hemorrhagic shock (6) and have been felt to be toxic. Because the ingestion of abnormal heme pigments by histiocytes may be part of a defense mechanism, we have attempted to correlate the percentage of iron laden histiocytes found in the tracheobronchial secretions of patients in hemorrhagic shock (Prussian blue method) with the presence of degradation of products of hemoglobin found in their serum by scanning spectrophotometry. There were, generally speaking, few iron laden histiocytes when hemoglobin degradation was advanced, and always numerous iron laden histiocytes when abnormal heme pigments were absent or spectrophotometric findings revealed minor degrees of degradation. Our findings probably reflect the process in the reticuloendothelial systems which eliminates toxic products accumulating in the circulation in low-flow states.

  16. Decrease in nicotinamide adenine dinucleotide dehydrogenase is related to skin pigmentation.

    PubMed

    Nakama, Mitsuo; Murakami, Yuhko; Tanaka, Hiroshi; Nakata, Satoru

    2012-03-01

    Skin pigmentation is caused by various physical and chemical factors. It might also be influenced by changes in the physiological function of skin with aging. Nicotinamide adenine dinucleotide (NADH) dehydrogenase is an enzyme related to the mitochondrial electron transport system and plays a key role in cellular energy production. It has been reported that the functional decrease in this system causes Parkinson's disease. Another study reports that the amount of NADH dehydrogenase in heart and skeletal muscle decreases with aging. A similar decrease in the skin would probably affect its physiological function. However, no reports have examined the age-related change in levels of NADH dehydrogenase in human skin. In this study, we investigated this change and its effect on skin pigmentation using cultured human epidermal keratinocytes. The mRNA expression of NDUFA1, NDUFB7, and NDUFS2, subunits of NADH dehydrogenase, and its activity were significantly decreased in late passage keratinocytes compared to early passage cells. Conversely, the mRNA expression of melanocyte-stimulating cytokines, interleukin-1 alpha and endothelin 1, was increased in late passage cells. On the other hand, the inhibition of NADH dehydrogenase upregulated the mRNA expression of melanocyte-stimulating cytokines. Moreover, the level of NDUFB7 mRNA was lower in pigmented than in nonpigmented regions of skin in vivo. These results suggest the decrease in NADH dehydrogenase with aging to be involved in skin pigmentation.

  17. Skin regeneration for giant pigmented nevus using autologous cultured dermal substitutes and epidermis separated from nevus skin.

    PubMed

    Kobayashi, Shinji; Kubo, Kentarou; Matsui, Hiromichi; Torikai, Katuyuki; Kuroyanagi, Yoshimitsu

    2006-02-01

    We have developed a modality of treatment of giant pigmented nevus of intradermal type. This method involves application of autologous cultured dermal substitute (CDS), followed by grafting of epidermis separated from the patient's nevus skin. To prepare the wound bed, autologous CDS was applied onto a full-thickness skin defect after complete excision of the nevus. The excised nevus skin was preserved for 1 week, after which the epidermis was separated from the nevus skin by enzymatic treatment with dispase. The epidermis thus obtained was grafted onto the resulting wound bed. This procedure was used to treat a giant pigmented nevus on a 7-year-old patient. The grafted region was soft with good tone 1 year after epidermis grafting. These results indicate that the present method can achieve complete excision of giant nevus, with esthetically acceptable results, although it requires careful monitoring for a long time.

  18. Platelet storage pool deficiency associated with inherited abnormalities of the inner ear in the mouse pigment mutants muted and mocha.

    PubMed

    Swank, R T; Reddington, M; Howlett, O; Novak, E K

    1991-10-15

    Several inherited human syndromes have combined platelet, auditory, and/or pigment abnormalities. In the mouse the pallid pigment mutant has abnormalities of the otoliths of the inner ear together with a bleeding abnormality caused by platelet storage pool deficiency (SPD). To determine if this association is common, two other mouse pigment mutants, muted and mocha, which are known to have inner ear abnormalities, were examined for hematologic abnormalities. Both mutants had prolonged bleeding times accompanied by abnormalities of dense granules as determined by whole mount electron microscopy of platelets and by labeling platelets with mepacrine. When mutant platelets were treated with collagen, there was minimal secretion of adenosine triphosphate and aggregation was reduced. Lysosomal enzyme secretion in response to thrombin treatment was partially reduced in muted platelets and markedly reduced in mocha platelets. Similar reductions in constitutive lysosomal enzyme secretion from kidney proximal tubule cells were noted in the two mutants. These studies show that several mutations that cause pigment dilution and platelet SPD are associated with abnormalities of the inner ear. Also, these mutants, like previously described mouse pigment mutants, are models for human Hermansky-Pudlak syndrome and provide additional examples of single genes that simultaneously affect melanosomes, lysosomes, and platelet dense granules.

  19. Estimation of Fractal Dimension in Differential Diagnosis of Pigmented Skin Lesions

    NASA Astrophysics Data System (ADS)

    Aralica, Gorana; Milošević, Danko; Konjevoda, Paško; Seiwerth, Sven; Štambuk, Nikola

    Medical differential diagnosis is a method of identifying the presence of a particular entity (disease) within a set of multiple possible alternatives. The significant problem in dermatology and pathology is the differential diagnosis of malignant melanoma and other pigmented skin lesions, especially of dysplastic nevi. Malignant melanoma is the most malignant skin neoplasma, with increasing incidence in various parts of the world. It is hoped that the methods of quantitative pathology, i.e. morphometry, can help objectification of the diagnostic process, since early discovery of melanoma results in 10-year survival rate of 90%. The aim of the study was to use fractal dimension calculated from the perimeter-area relation of the cell nuclei as a tool for the differential diagnosis of pigmented skin lesions. We analyzed hemalaun-eosin stained pathohistological slides of pigmented skin lesions: intradermal naevi (n = 45), dysplastic naevi (n = 47), and malignant melanoma (n = 50). It was found that fractal dimension of malignant melanoma cell nuclei differs significantly from the intradermal and dysplastic naevi (p ≤ 0. 001, Steel-Dwass Multiple Comparison Test). Additionaly, ROC analysis confirmed the value of fractal dimension based evaluation. It is suggested that the estimation of fractal dimension from the perimeter-area relation of the cell nuclei may be a potentially useful morphometric parameter in the medical differential diagnosis of pigmented skin lesions.

  20. N-Nicotinoyl dopamine, a novel niacinamide derivative, retains high antioxidant activity and inhibits skin pigmentation.

    PubMed

    Kim, Bora; Kim, Jin Eun; Lee, Su Min; Lee, Soung-Hoon; Lee, Jin Won; Kim, Myung Kyoo; Lee, Kye Jong; Kim, Hyuk; Lee, Joo Dong; Choi, Kang-Yell

    2011-11-01

    We synthesized a novel derivative of a well-known skin-lightening compound niacinamide, N-nicotinoyl dopamine (NND). NND did not show inhibitory effects of tyrosinase and melanin synthesis in B16F10 mouse melanoma cells. However, NND retains high antioxidant activity without affecting viability of cells. In a reconstructed skin model, topical applications of 0.05% and 0.1% NND induced skin lightening and decreased melanin production without affecting the viability and morphology of melanocytes and overall tissue histology. Moreover, no evidence for skin irritation or sensitization was observed when 0.1% NND emulsion was applied onto the skin of 52 volunteers. The effect of NND on skin lightening was further revealed by pigmented spot analyses of human clinical trial. Overall, NND treatment may be a useful trial for skin lightening and treating pigmentary disorders.

  1. Was skin cancer a selective force for black pigmentation in early hominin evolution?

    PubMed

    Greaves, Mel

    2014-04-22

    Melanin provides a crucial filter for solar UV radiation and its genetically determined variation influences both skin pigmentation and risk of cancer. Genetic evidence suggests that the acquisition of a highly stable melanocortin 1 receptor allele promoting black pigmentation arose around the time of savannah colonization by hominins at some 1-2 Ma. The adaptive significance of dark skin is generally believed to be protection from UV damage but the pathologies that might have had a deleterious impact on survival and/or reproductive fitness, though much debated, are uncertain. Here, I suggest that data on age-associated cancer incidence and lethality in albinos living at low latitudes in both Africa and Central America support the contention that skin cancer could have provided a potent selective force for the emergence of black skin in early hominins.

  2. Was skin cancer a selective force for black pigmentation in early hominin evolution?

    PubMed Central

    Greaves, Mel

    2014-01-01

    Melanin provides a crucial filter for solar UV radiation and its genetically determined variation influences both skin pigmentation and risk of cancer. Genetic evidence suggests that the acquisition of a highly stable melanocortin 1 receptor allele promoting black pigmentation arose around the time of savannah colonization by hominins at some 1–2 Ma. The adaptive significance of dark skin is generally believed to be protection from UV damage but the pathologies that might have had a deleterious impact on survival and/or reproductive fitness, though much debated, are uncertain. Here, I suggest that data on age-associated cancer incidence and lethality in albinos living at low latitudes in both Africa and Central America support the contention that skin cancer could have provided a potent selective force for the emergence of black skin in early hominins. PMID:24573849

  3. Primary Cilia Negatively Regulate Melanogenesis in Melanocytes and Pigmentation in a Human Skin Model

    PubMed Central

    Kim, Eun Sung; Park, So Jung; Bae, Il-Hong; Jo, Yoon Kyung; Jeong, In Young; Kim, Hyoung-June; Lee, Youngjin; Park, Hea Chul; Jeon, Hong Bae; Kim, Ki Woo; Lee, Tae Ryong; Cho, Dong-Hyung

    2016-01-01

    The primary cilium is an organelle protruding from the cell body that senses external stimuli including chemical, mechanical, light, osmotic, fluid flow, and gravitational signals. Skin is always exposed to the external environment and responds to external stimuli. Therefore, it is possible that primary cilia have an important role in skin. Ciliogenesis was reported to be involved in developmental processes in skin, such as keratinocyte differentiation and hair formation. However, the relation between skin pigmentation and primary cilia is largely unknown. Here, we observed that increased melanogenesis in melanocytes treated with a melanogenic inducer was inhibited by a ciliogenesis inducer, cytochalasin D, and serum-free culture. However, these inhibitory effects disappeared in GLI2 knockdown cells. In addition, activation of sonic hedgehog (SHH)-smoothened (Smo) signaling pathway by a Smo agonist, SAG inhibited melanin synthesis in melanocytes and pigmentation in a human skin model. On the contrary, an inhibitor of primary cilium formation, ciliobrevin A1, activated melanogenesis in melanocytes. These results suggest that skin pigmentation may be regulated partly by the induction of ciliogenesis through Smo-GLI2 signaling. PMID:27941997

  4. Nitisinone improves eye and skin pigmentation defects in a mouse model of oculocutaneous albinism.

    PubMed

    Onojafe, Ighovie F; Adams, David R; Simeonov, Dimitre R; Zhang, Jun; Chan, Chi-Chao; Bernardini, Isa M; Sergeev, Yuri V; Dolinska, Monika B; Alur, Ramakrishna P; Brilliant, Murray H; Gahl, William A; Brooks, Brian P

    2011-10-01

    Mutation of the tyrosinase gene (TYR) causes oculocutaneous albinism, type 1 (OCA1), a condition characterized by reduced skin and eye melanin pigmentation and by vision loss. The retinal pigment epithelium influences postnatal visual development. Therefore, increasing ocular pigmentation in patients with OCA1 might enhance visual function. There are 2 forms of OCA1, OCA-1A and OCA-1B. Individuals with the former lack functional tyrosinase and therefore lack melanin, while individuals with the latter produce some melanin. We hypothesized that increasing plasma tyrosine concentrations using nitisinone, an FDA-approved inhibitor of tyrosine degradation, could stabilize tyrosinase and improve pigmentation in individuals with OCA1. Here, we tested this hypothesis in mice homozygous for either the Tyrc-2J null allele or the Tyrc-h allele, which model OCA-1A and OCA-1B, respectively. Only nitisinone-treated Tyrc-h/c-h mice manifested increased pigmentation in their fur and irides and had more pigmented melanosomes. High levels of tyrosine improved the stability and enzymatic function of the Tyrc-h protein and also increased overall melanin levels in melanocytes from a human with OCA-1B. These results suggest that the use of nitisinone in OCA-1B patients could improve their pigmentation and potentially ameliorate vision loss.

  5. Pigmented squamous cell carcinoma of the cheek skin probably arising from solar keratosis.

    PubMed

    Terada, Tadashi; Yamagami, Jun; Fugimoto, Atsushi; Tanaka, Kyoko; Sugiura, Makoto

    2003-07-01

    We report a rare case of pigmented squamous cell carcinoma (SCC) of the cheek skin probably arising from solar keratosis. An 80-year-old man was referred to our clinic because of a black skin nodule in the right cheek. The nodular lesion was 1 cm in diameter, dome-shaped, hard, sharply demarcated, partially erosive and telangiectatic at the border. The lesion was completely excised under the clinical diagnosis of probable seborrheic keratosis. Microscopically, cutaneous horn and mildly atypical squamous epithelia suggestive of previous solar keratosis were present in the surface of the lesion. The lesion consisted of atypical squamous cells with keratinization and intercellular bridges, and it was regarded as SCC. The SCC cells were seen to invade lightly into the upper dermis, where lymphocytic infiltrations and melanophages were noted. Characteristically, heavy deposition of melanin pigment was recognized in the SCC cells as well as in proliferated dendritic and pigment blockade melanocytes that were scattered or colonized within the SCC cell nests. Masson-Fontana stain revealed numerous melanin granules in the SCC cells, as well as in dendritic and pigment blockade melanocytes. Immunohistochemically, the SCC cells were positive for cytokeratins and epithelial membrane antigen, and negative for S-100 protein and HMB45 antigen. Dendritic and pigment blockade melanocytes were negative for cytokeratins, epithelial membrane antigen, and HMB45 antigen, but positive for S-100 protein. The present case suggests that SCC cells of the skin may induce proliferation of melanocytes. The differential diagnosis and the histogenesis of pigmented SCC of the skin are discussed.

  6. Key Regulatory Role of Dermal Fibroblasts in Pigmentation as Demonstrated Using a Reconstructed Skin Model: Impact of Photo-Aging

    PubMed Central

    Duval, Christine; Cohen, Catherine; Chagnoleau, Corinne; Flouret, Virginie; Bourreau, Emilie; Bernerd, Françoise

    2014-01-01

    To study cutaneous pigmentation in a physiological context, we have previously developed a functional pigmented reconstructed skin model composed of a melanocyte-containing epidermis grown on a dermal equivalent comprising living fibroblasts. The present studies, using the same model, aimed to demonstrate that dermal fibroblasts influence skin pigmentation up to the macroscopic level. The proof of principle was performed with pigmented skins differing only in the fibroblast component. First, the in vitro system was reconstructed with or without fibroblasts in order to test the global influence of the presence of this cell type. We then assessed the impact of the origin of the fibroblast strain on the degree of pigmentation using fetal versus adult fibroblasts. In both experiments, impressive variation in skin pigmentation at the macroscopic level was observed and confirmed by quantitative parameters related to skin color, melanin content and melanocyte numbers. These data confirmed the responsiveness of the model and demonstrated that dermal fibroblasts do indeed impact the degree of skin pigmentation. We then hypothesized that a physiological state associated with pigmentary alterations such as photo-aging could be linked to dermal fibroblasts modifications that accumulate over time. Pigmentation of skin reconstructed using young unexposed fibroblasts (n = 3) was compared to that of tissues containing natural photo-aged fibroblasts (n = 3) which express a senescent phenotype. A stimulation of pigmentation in the presence of the natural photo-aged fibroblasts was revealed by a significant increase in the skin color (decrease in Luminance) and an increase in both epidermal melanin content and melanogenic gene expression, thus confirming our hypothesis. Altogether, these data demonstrate that the level of pigmentation of the skin model is influenced by dermal fibroblasts and that natural photo-aged fibroblasts can contribute to the hyperpigmentation that is

  7. An ICA-based method for the segmentation of pigmented skin lesions in macroscopic images.

    PubMed

    Cavalcanti, Pablo G; Scharcanski, Jacob; Di Persia, Leandro E; Milone, Diego H

    2011-01-01

    Segmentation is an important step in computer-aided diagnostic systems for pigmented skin lesions, since that a good definition of the lesion area and its boundary at the image is very important to distinguish benign from malignant cases. In this paper a new skin lesion segmentation method is proposed. This method uses Independent Component Analysis to locate skin lesions in the image, and this location information is further refined by a Level-set segmentation method. Our method was evaluated in 141 images and achieved an average segmentation error of 16.55%, lower than the results for comparable state-of-the-art methods proposed in literature.

  8. 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.

  9. Update on the regulation of mammalian melanocyte function and skin pigmentation

    PubMed Central

    Kondo, Taisuke; Hearing, Vincent J

    2011-01-01

    Melanogenesis is the unique process of producing pigmented biopolymers that are sequestered within melanosomes, which provides color to the skin, hair and eyes of animals and, in the case of human skin, also protects the underlying tissues from UV damage. We review the current understanding of melanogenesis, focusing on factors important to the biochemistry of pigment synthesis, the biogenesis of melanosomes, signaling pathways and factors that regulate melanogenesis, intramelanosomal pH, transport and transfer of melanosomes, and pigmentary disorders related to the dysfunction of melanosome-related proteins. Although it has been known for some time that many of the factors that affect melanogenesis are derived from keratinocytes, fibroblasts, endothelial cells, hormones, inflammatory cells and nerves, a number of new factors that are involved in that regulation have recently been reported, such as factors that regulate melanosome pH and ion transport. PMID:21572549

  10. UV exposure modulates hemidesmosome plasticity, contributing to long-term pigmentation in human skin.

    PubMed

    Coelho, Sergio G; Valencia, Julio C; Yin, Lanlan; Smuda, Christoph; Mahns, Andre; Kolbe, Ludger; Miller, Sharon A; Beer, Janusz Z; Zhang, Guofeng; Tuma, Pamela L; Hearing, Vincent J

    2015-05-01

    Human skin colour, ie pigmentation, differs widely among individuals, as do their responses to various types of ultraviolet radiation (UV) and their risks of skin cancer. In some individuals, UV-induced pigmentation persists for months to years in a phenomenon termed long-lasting pigmentation (LLP). It is unclear whether LLP is an indicator of potential risk for skin cancer. LLP seems to have similar features to other forms of hyperpigmentation, eg solar lentigines or age spots, which are clinical markers of photodamage and risk factors for precancerous lesions. To investigate what UV-induced molecular changes may persist in individuals with LLP, clinical specimens from non-sunburn-inducing repeated UV exposures (UVA, UVB or UVA + UVB) at 4 months post-exposure (short-term LLP) were evaluated by microarray analysis and dataset mining. Validated targets were further evaluated in clinical specimens from six healthy individuals (three LLP+ and three LLP-) followed for more than 9 months (long-term LLP) who initially received a single sunburn-inducing UVA + UVB exposure. The results support a UV-induced hyperpigmentation model in which basal keratinocytes have an impaired ability to remove melanin that leads to a compensatory mechanism by neighbouring keratinocytes with increased proliferative capacity to maintain skin homeostasis. The attenuated expression of SOX7 and other hemidesmosomal components (integrin α6β4 and plectin) leads to increased melanosome uptake by keratinocytes and points to a spatial regulation within the epidermis. The reduced density of hemidesmosomes provides supporting evidence for plasticity at the epidermal-dermal junction. Altered hemidesmosome plasticity, and the sustained nature of LLP, may be mediated by the role of SOX7 in basal keratinocytes. The long-term sustained subtle changes detected are modest, but sufficient to create dramatic visual differences in skin colour. These results suggest that the hyperpigmentation phenomenon

  11. UV exposure modulates hemidesmosome plasticity, contributing to long-term pigmentation in human skin

    PubMed Central

    Coelho, Sergio G.; Valencia, Julio C.; Yin, Lanlan; Smuda, Christoph; Mahns, Andre; Kolbe, Ludger; Miller, Sharon A.; Beer, Janusz Z.; Zhang, Guofeng; Tuma, Pamela L.; Hearing, Vincent J.

    2014-01-01

    Human skin color, i.e. pigmentation, differs widely among individuals as do their responses to various types of ultraviolet radiation (UV) and their risks of skin cancer. In some individuals UV-induced pigmentation persists for months to years in a phenomenon termed long-lasting pigmentation (LLP). It is unclear whether LLP is an indicator of potential risk for skin cancer. LLP seems to have similar features to other forms of hyperpigmentation, e.g. solar lentigines or age spots, which are clinical markers of photodamage and risk factors for precancerous lesions. To investigate what UV-induced molecular changes may persist in individuals with LLP, clinical specimens from non-sunburn-inducing repeated UV exposures (UVA, UVB or UVA+UVB) at 4 months post-exposure (short-term LLP) were evaluated by microarray analysis and dataset mining. Validated targets were further evaluated in clinical specimens from 6 healthy individuals (3 LLP+ and 3 LLP-) followed for more than 9 months (long-term LLP) who initially received a single sunburn-inducing UVA+UVB exposure. The results support a UV-induced hyperpigmentation model in which basal keratinocytes have an impaired ability to remove melanin that leads to a compensatory mechanism by neighboring keratinocytes with increased proliferative capacity to maintain skin homeostasis. The attenuated expression of SOX7 and other hemidesmosomal components (integrin α6β4 and plectin) leads to increased melanosome uptake by keratinocytes and points to a spatial regulation within the epidermis. The reduced density of hemidesmosomes provides supporting evidence for plasticity at the epidermal-dermal junction. Altered hemidesmosome plasticity, and the sustained nature of LLP, may be mediated by the role of SOX7 in basal keratinocytes. The long-term sustained subtle changes detected are modest, but sufficient to create dramatic visual differences in skin color. These results suggest that the hyperpigmentation phenomenon leading to increased

  12. In ovo gene manipulation of melanocytes and their adjacent keratinocytes during skin pigmentation of chicken embryos.

    PubMed

    Murai, Hidetaka; Tadokoro, Ryosuke; Sakai, Ken-Ichiro; Takahashi, Yoshiko

    2015-04-01

    During skin pigmentation in avians and mammalians, melanin is synthesized in the melanocytes, and subsequently transferred to adjacently located keratinocytes, leading to a wide coverage of the body surface by melanin-containing cells. The behavior of melanocytes is influenced by keratinocytes shown mostly by in vitro studies. However, it has poorly been investigated how such intercellular cross-talk is regulated in vivo because of a lack of suitable experimental models. Using chicken embryos, we developed a method that enables in vivo gene manipulations of melanocytes and keratinocytes, where these cells are separately labeled by different genes. Two types of gene transfer techniques were combined: one was a retrovirus-mediated gene infection into the skin/keratinocytes, and the other was the in ovo DNA electroporation into neural crest cells, the origin of melanocytes. Since the Replication-Competent Avian sarcoma-leukosis virus long terminal repeat with Splice acceptor (RCAS) infection was available only for the White leghorn strain showing little pigmentation, melanocytes prepared from the Hypeco nera (pigmented) were back-transplanted into embryos of White leghorn. Prior to the transplantation, enhanced green fluorescent protein (EGFP)(+) Neo(r+) -electroporated melanocytes from Hypeco nera were selectively grown in G418-supplemented medium. In the skin of recipient White leghorn embryos infected with RCAS-mOrange, mOrange(+) keratinocytes and transplanted EGFP(+) melanocytes were frequently juxtaposed each other. High-resolution confocal microscopy also revealed that transplanted melanocytes exhibited normal behaviors regarding distribution patterns of melanocytes, dendrite morphology, and melanosome transfer. The method described in this study will serve as a useful tool to understand the mechanisms underlying intercellular regulations during skin pigmentation in vivo.

  13. Molecular changes in skin pigmented lesions of the coral trout Plectropomus leopardus.

    PubMed

    Lerebours, Adélaïde; Chapman, Emma C; Sweet, Michael J; Heupel, Michelle R; Rotchell, Jeanette M

    2016-09-01

    A high prevalence of skin pigmented lesions of 15% was recently reported in coral trout Plectropomus leopardus, a commercially important marine fish, inhabiting the Great Barrier Reef. Herein, fish were sampled at two offshore sites, characterised by high and low lesion prevalence. A transcriptomic approach using the suppressive subtractive hybridisation (SSH) method was used to analyse the differentially expressed genes between lesion and normal skin samples. Transcriptional changes of 14 genes were observed in lesion samples relative to normal skin samples. These targeted genes encoded for specific proteins which are involved in general cell function but also in different stages disrupted during the tumourigenesis process of other organisms, such as cell cycling, cell proliferation, skeletal organisation and cell migration. The results highlight transcripts that are associated with the lesion occurrence, contributing to a better understanding of the molecular aetiology of this coral trout skin disease.

  14. A case report of disappearing pigmented skin lesions associated with pembrolizumab treatment for metastatic melanoma.

    PubMed

    Wolner, Z J; Marghoob, A A; Pulitzer, M P; Postow, M A; Marchetti, M A

    2017-01-28

    Pembrolizumab is an immune checkpoint inhibitor that targets the programmed cell death (PD)-1 receptor. Common cutaneous adverse side effects of PD-1 inhibitors include maculopapular rash, pruritus, vitiligo, and lichenoid skin and mucosal reactions. Here, we describe a man in his sixties with metastatic melanoma treated with pembrolizumab who subsequently developed fading or disappearance of pigmented skin lesions, lightening of the skin, and poliosis of the eyebrows, eyelashes, and scalp and body hair. Compared to baseline high-resolution three-dimensional total body photography, we observed fading or disappearing of solar lentigines, seborrheic keratoses, and melanocytic naevi, suggesting that PD-1 inhibitors may affect the evolution of these benign skin lesions. With dermatoscopic follow-up, altered lesions showed either blue-grey peppering/granularity or fading in colour without other identifiable features. No halo lesions or lesions with surrounding inflammation were identified. One changed pigmented lesion that showed blue-grey peppering/granularity on dermoscopy was biopsied and interpreted as a macular seborrheic keratosis with melanophages. Further studies are required to elucidate the effects of PD-1 inhibition on benign skin lesions. This article is protected by copyright. All rights reserved.

  15. Diagnostics of pigmented skin tumors based on laser-induced autofluorescence and diffuse reflectance spectroscopy

    SciTech Connect

    Borisova, E; Avramov, L; Troyanova, P; Pavlova, P

    2008-06-30

    Results of investigation of cutaneous benign and malignant pigmented lesions by laser-induced autofluorescence spectroscopy (LIAFS) and diffuse reflectance spectroscopy (DRS) are presented. The autofluorescence of human skin was excited by a 337-nm nitrogen laser. A broadband halogen lamp (400-900 nm) was used for diffuse reflectance measurements. A microspectrometer detected in vivo the fluorescence and reflectance signals from human skin. The main spectral features of benign (dermal nevi, compound nevi, dysplastic nevi) and malignant (melanoma) lesions are discussed. The combined usage of the fluorescence and reflectance spectral methods to determine the type of the lesion, which increases the total diagnostic accuracy, is compared with the usage of LIAFS or DRS only. We also applied colorimetric transformation of the reflectance spectra detected and received additional evaluation criteria for determination of type of the lesion under study. Spectra from healthy skin areas near the lesion were detected and changes between healthy and lesion skin spectra were revealed. The influence of the main skin pigments on the detected spectra is discussed and evaluation of possibilities for differentiation between malignant and benign lesions is performed based on their spectral properties. This research shows that the non-invasive and high-sensitive in vivo detection by means of appropriate light sources and detectors should be possible, related to the real-time determination of existing pathological conditions. (special issue devoted to application of laser technologies in biophotonics and biomedical studies)

  16. Genome-Wide Association Studies of Quantitatively Measured Skin, Hair, and Eye Pigmentation in Four European Populations

    PubMed Central

    Candille, Sophie I.; Absher, Devin M.; Beleza, Sandra; Bauchet, Marc; McEvoy, Brian; Garrison, Nanibaa’ A.; Li, Jun Z.; Myers, Richard M.; Barsh, Gregory S.; Tang, Hua; Shriver, Mark D.

    2012-01-01

    Pigmentation of the skin, hair, and eyes varies both within and between human populations. Identifying the genes and alleles underlying this variation has been the goal of many candidate gene and several genome-wide association studies (GWAS). Most GWAS for pigmentary traits to date have been based on subjective phenotypes using categorical scales. But skin, hair, and eye pigmentation vary continuously. Here, we seek to characterize quantitative variation in these traits objectively and accurately and to determine their genetic basis. Objective and quantitative measures of skin, hair, and eye color were made using reflectance or digital spectroscopy in Europeans from Ireland, Poland, Italy, and Portugal. A GWAS was conducted for the three quantitative pigmentation phenotypes in 176 women across 313,763 SNP loci, and replication of the most significant associations was attempted in a sample of 294 European men and women from the same countries. We find that the pigmentation phenotypes are highly stratified along axes of European genetic differentiation. The country of sampling explains approximately 35% of the variation in skin pigmentation, 31% of the variation in hair pigmentation, and 40% of the variation in eye pigmentation. All three quantitative phenotypes are correlated with each other. In our two-stage association study, we reproduce the association of rs1667394 at the OCA2/HERC2 locus with eye color but we do not identify new genetic determinants of skin and hair pigmentation supporting the lack of major genes affecting skin and hair color variation within Europe and suggesting that not only careful phenotyping but also larger cohorts are required to understand the genetic architecture of these complex quantitative traits. Interestingly, we also see that in each of these four populations, men are more lightly pigmented in the unexposed skin of the inner arm than women, a fact that is underappreciated and may vary across the world. PMID:23118974

  17. Genome-wide association studies of quantitatively measured skin, hair, and eye pigmentation in four European populations.

    PubMed

    Candille, Sophie I; Absher, Devin M; Beleza, Sandra; Bauchet, Marc; McEvoy, Brian; Garrison, Nanibaa' A; Li, Jun Z; Myers, Richard M; Barsh, Gregory S; Tang, Hua; Shriver, Mark D

    2012-01-01

    Pigmentation of the skin, hair, and eyes varies both within and between human populations. Identifying the genes and alleles underlying this variation has been the goal of many candidate gene and several genome-wide association studies (GWAS). Most GWAS for pigmentary traits to date have been based on subjective phenotypes using categorical scales. But skin, hair, and eye pigmentation vary continuously. Here, we seek to characterize quantitative variation in these traits objectively and accurately and to determine their genetic basis. Objective and quantitative measures of skin, hair, and eye color were made using reflectance or digital spectroscopy in Europeans from Ireland, Poland, Italy, and Portugal. A GWAS was conducted for the three quantitative pigmentation phenotypes in 176 women across 313,763 SNP loci, and replication of the most significant associations was attempted in a sample of 294 European men and women from the same countries. We find that the pigmentation phenotypes are highly stratified along axes of European genetic differentiation. The country of sampling explains approximately 35% of the variation in skin pigmentation, 31% of the variation in hair pigmentation, and 40% of the variation in eye pigmentation. All three quantitative phenotypes are correlated with each other. In our two-stage association study, we reproduce the association of rs1667394 at the OCA2/HERC2 locus with eye color but we do not identify new genetic determinants of skin and hair pigmentation supporting the lack of major genes affecting skin and hair color variation within Europe and suggesting that not only careful phenotyping but also larger cohorts are required to understand the genetic architecture of these complex quantitative traits. Interestingly, we also see that in each of these four populations, men are more lightly pigmented in the unexposed skin of the inner arm than women, a fact that is underappreciated and may vary across the world.

  18. Genotype-Phenotype Study of the Middle Gangetic Plain in India Shows Association of rs2470102 with Skin Pigmentation.

    PubMed

    Mishra, Anshuman; Nizammuddin, Sheikh; Mallick, Chandana Basu; Singh, Sakshi; Prakash, Satya; Siddiqui, Niyamat Ali; Rai, Niraj; Carlus, S Justin; Sudhakar, Digumarthi V S; Tripathi, Vishnu P; Möls, Märt; Kim-Howard, Xana; Dewangan, Hemlata; Mishra, Abhishek; Reddy, Alla G; Roy, Biswajit; Pandey, Krishna; Chaubey, Gyaneshwer; Das, Pradeep; Nath, Swapan K; Singh, Lalji; Thangaraj, Kumarasamy

    2017-03-01

    Our understanding of the genetics of skin pigmentation has been largely skewed towards populations of European ancestry, imparting less attention to South Asian populations, who behold huge pigmentation diversity. Here, we investigate skin pigmentation variation in a cohort of 1,167 individuals in the Middle Gangetic Plain of the Indian subcontinent. Our data confirm the association of rs1426654 with skin pigmentation among South Asians, consistent with previous studies, and also show association for rs2470102 single nucleotide polymorphism. Our haplotype analyses further help us delineate the haplotype distribution across social categories and skin color. Taken together, our findings suggest that the social structure defined by the caste system in India has a profound influence on the skin pigmentation patterns of the subcontinent. In particular, social category and associated single nucleotide polymorphisms explain about 32% and 6.4%, respectively, of the total phenotypic variance. Phylogeography of the associated single nucleotide polymorphisms studied across 52 diverse populations of the Indian subcontinent shows wide presence of the derived alleles, although their frequencies vary across populations. Our results show that both polymorphisms (rs1426654 and rs2470102) play an important role in the skin pigmentation diversity of South Asians.

  19. Pigmented guinea pig skin irradiated with Q-switched ruby laser pulses. Morphologic and histologic findings

    SciTech Connect

    Dover, J.S.; Margolis, R.J.; Polla, L.L.; Watanabe, S.; Hruza, G.J.; Parrish, J.A.; Anderson, R.R.

    1989-01-01

    Q-switched ruby laser pulses cause selective damage to cutaneous pigmented cells. Repair of this selective damage has not been well described. Therefore, using epilated pigmented and albino guinea pig skin, we studied the acute injury and tissue repair caused by 40-ns, Q-switched ruby laser pulses. Gross observation and light and electron microscopy were performed. No specific changes were evident in the albino guinea pigs. In pigmented animals, with radiant exposures of 0.4 J/cm2 or greater, white spots confined to the 2.5-mm exposure sites developed immediately and faded over 20 minutes. Delayed depigmentation occurred at seven to ten days, followed by full repigmentation by four to eight weeks. Regrowing hairs in sites irradiated at and above 0.4 J/cm2 remained white for at least four months. Histologically, vacuolation of pigment-laden cells was seen immediately in the epidermis and the follicular epithelium at exposures of 0.3 J/cm2 and greater. Melanosomal disruption was seen immediately by electron microscopy at and above 0.3 J/cm2. Over the next seven days, epidermal necrosis was followed by regeneration of a depigmented epidermis. By four months, melanosomes and melanin pigmentation had returned; however, hair follicles remained depigmented and devoid of melanocytes. This study demonstrates that selective melanosomal disruption caused by Q-switched ruby laser pulses leads to transient cutaneous depigmentation and persistent follicular depigmentation. Potential exists for selective treatment of pigmented epidermal and dermal lesions with this modality.

  20. Relatively Permanent Pigmented or Vascular Skin Marks for Identification: A Pilot Reliability Study.

    PubMed

    Nurhudatiana, Arfika; Kong, Adams Wai-Kin; Craft, Noah; Tey, Hong Liang

    2016-01-01

    In child sexual exploitation offenses, the collected evidence images often show the skin of nonfacial body parts of the criminals and victims. For identification in this scenario, "relatively permanent pigmented or vascular skin marks," abbreviated as RPPVSM, were recently introduced as the basis for a novel biometric trait. This pilot study evaluated the interexaminer variability of RPPVSM identification. Four dermatology physicians were recruited to examine RPPVSM from 75 skin images collected from a total of 51 Caucasian and Asian subjects. The images were separated into 50 reference ("suspect") images and 25 evaluation ("evidence") images. The examiners were asked to perform identification by annotating RPPVSM in each of the 25 evaluation images and matching them with the reference images. The rate of misidentification was 0% while the mean rate at which examiners failed to find a match was 6%, indicating the potential of dermatology physicians performing the role of RPPVSM examiners.

  1. Topical application of a protein kinase C inhibitor reduces skin and hair pigmentation.

    PubMed

    Park, Hee-Young; Lee, Jin; González, Salvador; Middelkamp-Hup, Maritza A; Kapasi, Sameer; Peterson, Shaun; Gilchrest, Barbara A

    2004-01-01

    To determine whether inhibition of PKC-beta activity decreases pigmentation, paired cultures of primary human melanocytes were first pretreated with bisindolylmaleimide (Bis), a selective PKC inhibitor, or vehicle alone for 30 min, and then treated with TPA for an additional 90 min to activate PKC in the presence of Bis. Bis blocked the expected induction of tyrosinase activity by activation of PKC. Addition of a peptide corresponding to amino acids 501-511 of tyrosinase containing its PKC-beta phosphorylation site, a presumptive PKC-beta pseudosubstrate, gave similar results. To determine whether Bis reduces pigmentation in vivo, the backs of four shaved and depilated pigmented guinea pigs were UV irradiated with a solar simulator for 2 wk excluding weekends. Compared to vehicle alone, Bis (300 microM), applied twice daily to paired sites for various periods encompassing the irradiation period, decreased tanning. Bis also, although less strikingly, reduced basal epidermal melanin when topically applied twice daily, 5 d per wk, for 3 wk to shaved and depilated unirradiated skin. Moreover, topical application of Bis (100 microM) once daily for 9 d to the freshly depilated backs of 8-wk-old mice markedly lightened the color of regrowing hair. These results demonstrate that inhibiting PKC activity in vivo selectively blocks tanning and reduces basal pigmentation in the epidermis and in anagen hair shafts.

  2. Auto white balance method using a pigmentation separation technique for human skin color

    NASA Astrophysics Data System (ADS)

    Tanaka, Satomi; Kakinuma, Akihiro; Kamijo, Naohiro; Takahashi, Hiroshi; Tsumura, Norimichi

    2017-02-01

    The human visual system maintains the perception of colors of an object across various light sources. Similarly, current digital cameras feature an auto white balance function, which estimates the illuminant color and corrects the color of a photograph as if the photograph was taken under a certain light source. The main subject in a photograph is often a person's face, which could be used to estimate the illuminant color. However, such estimation is adversely affected by differences in facial colors among individuals. The present paper proposes an auto white balance algorithm based on a pigmentation separation method that separates the human skin color image into the components of melanin, hemoglobin and shading. Pigment densities have a uniform property within the same race that can be calculated from the components of melanin and hemoglobin in the face. We, thus, propose a method that uses the subject's facial color in an image and is unaffected by individual differences in facial color among Japanese people.

  3. Auto white balance method using a pigmentation separation technique for human skin color

    NASA Astrophysics Data System (ADS)

    Tanaka, Satomi; Kakinuma, Akihiro; Kamijo, Naohiro; Takahashi, Hiroshi; Tsumura, Norimichi

    2016-11-01

    The human visual system maintains the perception of colors of an object across various light sources. Similarly, current digital cameras feature an auto white balance function, which estimates the illuminant color and corrects the color of a photograph as if the photograph was taken under a certain light source. The main subject in a photograph is often a person's face, which could be used to estimate the illuminant color. However, such estimation is adversely affected by differences in facial colors among individuals. The present paper proposes an auto white balance algorithm based on a pigmentation separation method that separates the human skin color image into the components of melanin, hemoglobin and shading. Pigment densities have a uniform property within the same race that can be calculated from the components of melanin and hemoglobin in the face. We, thus, propose a method that uses the subject's facial color in an image and is unaffected by individual differences in facial color among Japanese people.

  4. Effects of low-level laser therapy, electroacupuncture, and radiofrequency on the pigmentation and skin tone of adult women

    PubMed Central

    Kim, Hee-Kyoung; Min, Kyoung-Ok; Choi, Jung-Hyun; Kim, Soon-Hee

    2016-01-01

    [Purpose] In this study, the effects of low-level laser therapy (LLLT), electroacupuncture (EA), and radiofrequency (RF), which are used in physical therapy, on the pigmentation and skin tone of adult women’s faces were investigated to provide basic data for skin interventions. [Subjects and Methods] Thirty adult females were assigned to either an LLLT group (n=10), an EA group (n=10), or an RF group (n=10). The intervention was performed in two 15-minute sessions per week for six weeks. Subjects’ skin tone and pigmentation were observed before and after the intervention. [Results] The EA group showed significant reductions in pigmentation in the left and right eye rims, as well as in the left cheek. The RF group showed significant post-intervention reductions in pigmentation under the left eye, as well as in the left and right eye rims and the left cheek. The LLLT group showed significant increases in skin tone in the forehead and both eye rims. The RF group showed significant increases in skin tone under both eyes. [Conclusion] The application of LLLT, EA, and RF had positive effects on pigmentation and skin tone of adult women’s faces. PMID:27313340

  5. Differentiation of Benign Pigmented Skin Lesions with the Aid of Computer Image Analysis: A Novel Approach

    PubMed Central

    Choi, Jae Woo; Park, Young Woon; Byun, Sang Young

    2013-01-01

    Background The differential diagnosis of common pigmented skin lesions is important in cosmetic dermatology. The computer aided image analysis would be a potent ancillary diagnostic tool when patients are hesitant to undergo a skin biopsy. Objective We investigated the numerical parameters discriminating each pigmented skin lesion from another with statistical significance. Methods For each of the five magnified digital images containing clinically diagnosed nevus, lentigo and seborrheic keratosis, a total of 23 parameters describing the morphological, color, texture and topological features were calculated with the aid of a self-developed image analysis software. A novel concept of concentricity was proposed, which represents how closely the color segmentation resembles a concentric circle. Results Morphologically, seborrheic keratosis was bigger and spikier than nevus and lentigo. The color histogram revealed that nevus was the darkest and had the widest variation in tone. In the aspect of texture, the surface of the nevus showed the highest contrast and correlation. Finally, the color segmented pattern of the nevus and lentigo was far more concentric than that of seborrheic keratosis. Conclusion We found that the subtle distinctions between nevus, lentigo and seborrheic keratosis, which are likely to be unrecognized by ocular inspection, are well emphasized and detected with the aid of software. PMID:24003278

  6. Abnormal thermal hyperaemia in the skin in paraplegia.

    PubMed

    Barbenel, J C; Cui, Z F

    1993-08-01

    Surface insulation, together with laser Doppler flowmetry, was used to assess the skin microcirculation of paraplegic patients. Two control groups of five male and five female subjects were used to establish the response of normals with which to compare the results obtained from six paraplegic subjects. No significant sex related difference was revealed from this study. It was found that in normal subjects, surface insulation resulted in a significant increase in both skin temperature and skin blood flow. In paraplegic patients, the temperature increase was significantly less than in the normal subjects and there was no significant thermally induced hyperaemia after surface insulation.

  7. Functional Assessment of Human Coding Mutations Affecting Skin Pigmentation Using Zebrafish

    PubMed Central

    Tsetskhladze, Zurab R.; Canfield, Victor A.; Ang, Khai C.; Wentzel, Steven M.; Reid, Katherine P.; Berg, Arthur S.; Johnson, Stephen L.; Kawakami, Koichi; Cheng, Keith C.

    2012-01-01

    A major challenge in personalized medicine is the lack of a standard way to define the functional significance of the numerous nonsynonymous, single nucleotide coding variants that are present in each human individual. To begin to address this problem, we have used pigmentation as a model polygenic trait, three common human polymorphisms thought to influence pigmentation, and the zebrafish as a model system. The approach is based on the rescue of embryonic zebrafish mutant phenotypes by “humanized” zebrafish orthologous mRNA. Two hypomorphic polymorphisms, L374F in SLC45A2, and A111T in SLC24A5, have been linked to lighter skin color in Europeans. The phenotypic effect of a second coding polymorphism in SLC45A2, E272K, is unclear. None of these polymorphisms had been tested in the context of a model organism. We have confirmed that zebrafish albino fish are mutant in slc45a2; wild-type slc45a2 mRNA rescued the albino mutant phenotype. Introduction of the L374F polymorphism into albino or the A111T polymorphism into slc24a5 (golden) abolished mRNA rescue of the respective mutant phenotypes, consistent with their known contributions to European skin color. In contrast, the E272K polymorphism had no effect on phenotypic rescue. The experimental conclusion that E272K is unlikely to affect pigmentation is consistent with a lack of correlation between this polymorphism and quantitatively measured skin color in 59 East Asian humans. A survey of mutations causing human oculocutaneous albinism yielded 257 missense mutations, 82% of which are theoretically testable in zebrafish. The developed approach may be extended to other model systems and may potentially contribute to our understanding the functional relationships between DNA sequence variation, human biology, and disease. PMID:23071798

  8. Skin pigmentation, sun exposure and vitamin D levels in children of the Avon Longitudinal Study of Parents and Children

    PubMed Central

    2014-01-01

    Background It has been hypothesised that light skin pigmentation has arisen to ensure adequate levels of vitamin D as human populations moved out of Africa and into higher latitudes. Vitamin D, which is primarily obtained through exposure to sunlight (specifically ultraviolet radiation B (UVR-B)), has been inversely associated with several complex diseases. Greater sun exposure, on the other hand, is a well-known cause of skin cancer. The potential of UVR to be beneficial for some health outcomes but detrimental for others has prompted a public health debate on how to balance the positive and negative consequences of sun exposure. In this study we aimed to determine the validity of the evolutionary hypothesis linking lighter skin with higher vitamin D concentrations in a European population. Additionally, we aimed to examine the influence of pigmentation on personal behaviour towards sunlight exposure and the effects of this behaviour on vitamin D. Methods We combined genetic variants strongly associated with skin colour, tanning or freckling to create genetic scores for each of these phenotypes. We examined the association of the scores with pigmentary traits, sun exposure and serum 25-hydroxyvitamin D (25(OH)D) levels among children of the Avon Longitudinal Study of Parents and Children (ALSPAC, N = 661 to 5649). Results We found that fairer-skinned children, i.e. those with higher pigmentation score values, had higher levels of 25(OH)D (0.6 nmol/l; 95% CI 0.2, 1.0; per unit increase in skin colour score; N = 5649). These children also used more protection against the damaging effects of UVR. Conclusions In this population taking protective measures against sunburn and skin cancer does not seem to remove the positive effect that having a less pigmented skin has on vitamin D production. Our findings require further replication as skin pigmentation showed only a small effect on circulating 25(OH)D. PMID:24924479

  9. Clinical studies of pigmented lesions in human skin by using a multiphoton tomograph

    NASA Astrophysics Data System (ADS)

    Balu, Mihaela; Kelly, Kristen M.; Zachary, Christopher B.; Harris, Ronald M.; Krasieva, Tatiana B.; König, Karsten; Tromberg, Bruce J.

    2013-02-01

    In vivo imaging of pigmented lesions in human skin was performed with a clinical multiphoton microscopy (MPM)-based tomograph (MPTflex, JenLab, Germany). Two-photon excited fluorescence was used for visualizing endogenous fluorophores such as NADH/FAD, keratin, melanin in the epidermal cells and elastin fibers in the dermis. Collagen fibers were imaged by second harmonic generation. Our study involved in vivo imaging of benign melanocytic nevi, atypical nevi and melanoma. The goal of this preliminary study was to identify in vivo the characteristic features and their frequency in pigmented lesions at different stages (benign, atypical and malignant) and to evaluate the ability of in vivo MPM to distinguish atypical nevi from melanoma. Comparison with histopathology was performed for the biopsied lesions. Benign melanocytic nevi were characterized by the presence of nevus cell nests at the epidermal-dermal junction. In atypical nevi, features such as lentiginous hyperplasia, acanthosis and architectural disorder were imaged. Cytological atypia was present in all the melanoma lesions imaged, showing the strongest correlation with malignancy. The MPM images demonstrated very good correlation with corresponding histological images, suggesting that MPM could be a promising tool for in vivo non-invasive pigmented lesion diagnosis, particularly distinguishing atypical nevi from melanoma.

  10. Sex steroids regulate skin pigmentation through nonclassical membrane-bound receptors

    PubMed Central

    Natale, Christopher A; Duperret, Elizabeth K; Zhang, Junqian; Sadeghi, Rochelle; Dahal, Ankit; O'Brien, Kevin Tyler; Cookson, Rosa; Winkler, Jeffrey D; Ridky, Todd W

    2016-01-01

    The association between pregnancy and altered cutaneous pigmentation has been documented for over two millennia, suggesting that sex hormones play a role in regulating epidermal melanocyte (MC) homeostasis. Here we show that physiologic estrogen (17β-estradiol) and progesterone reciprocally regulate melanin synthesis. This is intriguing given that we also show that normal primary human MCs lack classical estrogen or progesterone receptors (ER or PR). Utilizing both genetic and pharmacologic approaches, we establish that sex steroid effects on human pigment synthesis are mediated by the membrane-bound, steroid hormone receptors G protein-coupled estrogen receptor (GPER), and progestin and adipoQ receptor 7 (PAQR7). Activity of these receptors was activated or inhibited by synthetic estrogen or progesterone analogs that do not bind to ER or PR. As safe and effective treatment options for skin pigmentation disorders are limited, these specific GPER and PAQR7 ligands may represent a novel class of therapeutics. DOI: http://dx.doi.org/10.7554/eLife.15104.001 PMID:27115344

  11. Skin pigmentation provides evidence of convergent melanism in extinct marine reptiles.

    PubMed

    Lindgren, Johan; Sjövall, Peter; Carney, Ryan M; Uvdal, Per; Gren, Johan A; Dyke, Gareth; Schultz, Bo Pagh; Shawkey, Matthew D; Barnes, Kenneth R; Polcyn, Michael J

    2014-02-27

    Throughout the animal kingdom, adaptive colouration serves critical functions ranging from inconspicuous camouflage to ostentatious sexual display, and can provide important information about the environment and biology of a particular organism. The most ubiquitous and abundant pigment, melanin, also has a diverse range of non-visual roles, including thermoregulation in ectotherms. However, little is known about the functional evolution of this important biochrome through deep time, owing to our limited ability to unambiguously identify traces of it in the fossil record. Here we present direct chemical evidence of pigmentation in fossilized skin, from three distantly related marine reptiles: a leatherback turtle, a mosasaur and an ichthyosaur. We demonstrate that dark traces of soft tissue in these fossils are dominated by molecularly preserved eumelanin, in intimate association with fossilized melanosomes. In addition, we suggest that contrary to the countershading of many pelagic animals, at least some ichthyosaurs were uniformly dark-coloured in life. Our analyses expand current knowledge of pigmentation in fossil integument beyond that of feathers, allowing for the reconstruction of colour over much greater ranges of extinct taxa and anatomy. In turn, our results provide evidence of convergent melanism in three disparate lineages of secondarily aquatic tetrapods. Based on extant marine analogues, we propose that the benefits of thermoregulation and/or crypsis are likely to have contributed to this melanisation, with the former having implications for the ability of each group to exploit cold environments.

  12. Possible contributions of skin pigmentation and vitamin D in a polyfactorial model of seasonal affective disorder.

    PubMed

    Stewart, Alan E; Roecklein, Kathryn A; Tanner, Susan; Kimlin, Michael G

    2014-11-01

    Seasonal affective disorder (SAD) is a polyfactorial and polygenetic disorder that involves biological and psychological sub-mechanisms that differentially involve depression, seasonality, circadian rhythms, retinal sensitivity, iris pigmentation, sleep factors, and the neurotransmitters involved with these systems. Within the framework of the polyfactorial conceptualization of SAD, we review the possible contributions of vitamin D3 with respect to the aforementioned sub-mechanisms. We hypothesize that rather than functioning primarily as a proximal or direct sub-mechanism in the etiology of SAD, vitamin D likely functions in a more foundational and regulative role in potentiating the sub-mechanisms associated with the depressive and seasonality factors. There are several reasons for this position: 1. vitamin D levels fluctuate in the body seasonally, with a lag, in direct relation to seasonally-available sunlight; 2. lower vitamin D levels have been observed in depressed patients (as well as in patients with other psychiatric disorders) compared to controls; 3. vitamin D levels in the central nervous system affect the production of both serotonin and dopamine; and 4. vitamin D and vitamin D responsive elements are found throughout the midbrain regions and are especially concentrated in the hypothalamus, a region that encompasses the circadian timing systems and much of its neural circuitry. We also consider the variable of skin pigmentation as this may affect levels of vitamin D in the body. We hypothesize that people with darker skin pigmentation may experience greater risks for lower vitamin D levels that, especially following their migration to regions of higher latitude, could contribute to the emergence of SAD and other psychiatric and physical health problems.

  13. Determination of the optical properties of melanin-pigmented human skin equivalents using terahertz time-domain spectroscopy

    NASA Astrophysics Data System (ADS)

    Lipscomb, Dawn; Echchgadda, Ibtissam; Peralta, Xomalin G.; Wilmink, Gerald J.

    2013-02-01

    Terahertz time-domain spectroscopy (THz-TDS) methods have been utilized in previous studies in order to characterize the optical properties of skin and its primary constituents (i.e., water, collagen, and keratin). However, similar experiments have not yet been performed to investigate whether melanocytes and the melanin pigment that they synthesize contribute to skin's optical properties. In this study, we used THz-TDS methods operating in transmission geometry to measure the optical properties of in vitro human skin equivalents with or without normal human melanocytes. Skin equivalents were cultured for three weeks to promote gradual melanogenesis, and THz time domain data were collected at various time intervals. Frequency-domain analysis techniques were performed to determine the index of refraction (n) and absorption coefficient (μa) for each skin sample over the frequency range of 0.1-2.0 THz. We found that for all samples as frequency increased, n decreased exponentially and the μa increased linearly. Additionally, we observed that skin samples with higher levels of melanin exhibited greater n and μa values than the non-pigmented samples. Our results indicate that melanocytes and the degree of melanin pigmentation contribute in an appreciable manner to the skin's optical properties. Future studies will be performed to examine whether these contributions are observed in human skin in vivo.

  14. The effects of topical and oral L-selenomethionine on pigmentation and skin cancer induced by ultraviolet irradiation.

    PubMed

    Burke, K E; Combs, G F; Gross, E G; Bhuyan, K C; Abu-Libdeh, H

    1992-01-01

    This study was conducted to determine whether oral and/or topical selenium (Se) supplementation can reduce the incidence of acute and/or chronic damage to the skin (i.e., sunburn and pigmentation and/or skin cancer, respectively) induced by ultraviolet (UV) irradiation in mice. Groups of 38 BALB:c female mice or 16 Skh:2 hairless pigmented mice were treated with 1) lotion vehicle, 2) 0.02% L-selenomethionine (SeMet) lotion, or 3) vehicle and 1.5 ppm SeMet in the drinking water. Within each group, 30 BALB:c mice or 12 Skh:2 mice were given UV irradiation (Westinghouse FS 40 bulbs) three times per week in doses of 0.575 and 0.24 J/cm2, respectively. The animals' weights and food intakes and the Se concentrations of skin and liver were measured. Skin biopsies were taken from the backs and abdomens of all animals to evaluate the relative amounts of Se and the damage by UV irradiation. Skin pigmentation was scored, and the total number of clinically detectable skin tumors per animal was counted weekly. Results showed that the skin Se concentrations in areas of application of the lotion containing SeMet were greater than those of animals given comparable oral doses, while the Se concentrations of untreated skin and liver were similar to those of animals receiving oral Se. Mice treated with Se showed no signs of toxicity and had significantly less skin damage by UV irradiation, as indicated by reduced inflammation and pigmentation and by later onset and lesser incidence of skin cancer.

  15. A genome-wide association study identifies novel alleles associated with hair color and skin pigmentation.

    PubMed

    Han, Jiali; Kraft, Peter; Nan, Hongmei; Guo, Qun; Chen, Constance; Qureshi, Abrar; Hankinson, Susan E; Hu, Frank B; Duffy, David L; Zhao, Zhen Zhen; Martin, Nicholas G; Montgomery, Grant W; Hayward, Nicholas K; Thomas, Gilles; Hoover, Robert N; Chanock, Stephen; Hunter, David J

    2008-05-16

    We conducted a multi-stage genome-wide association study of natural hair color in more than 10,000 men and women of European ancestry from the United States and Australia. An initial analysis of 528,173 single nucleotide polymorphisms (SNPs) genotyped on 2,287 women identified IRF4 and SLC24A4 as loci highly associated with hair color, along with three other regions encompassing known pigmentation genes. We confirmed these associations in 7,028 individuals from three additional studies. Across these four studies, SLC24A4 rs12896399 and IRF4 rs12203592 showed strong associations with hair color, with p = 6.0x10(-62) and p = 7.46x10(-127), respectively. The IRF4 SNP was also associated with skin color (p = 6.2x10(-14)), eye color (p = 6.1x10(-13)), and skin tanning response to sunlight (p = 3.9x10(-89)). A multivariable analysis pooling data from the initial GWAS and an additional 1,440 individuals suggested that the association between rs12203592 and hair color was independent of rs1540771, a SNP between the IRF4 and EXOC2 genes previously found to be associated with hair color. After adjustment for rs12203592, the association between rs1540771 and hair color was not significant (p = 0.52). One variant in the MATP gene was associated with hair color. A variant in the HERC2 gene upstream of the OCA2 gene showed the strongest and independent association with hair color compared with other SNPs in this region, including three previously reported SNPs. The signals detected in a region around the MC1R gene were explained by MC1R red hair color alleles. Our results suggest that the IRF4 and SLC24A4 loci are associated with human hair color and skin pigmentation.

  16. Pigmented skin lesion detection using random forest and wavelet-based texture

    NASA Astrophysics Data System (ADS)

    Hu, Ping; Yang, Tie-jun

    2016-10-01

    The incidence of cutaneous malignant melanoma, a disease of worldwide distribution and is the deadliest form of skin cancer, has been rapidly increasing over the last few decades. Because advanced cutaneous melanoma is still incurable, early detection is an important step toward a reduction in mortality. Dermoscopy photographs are commonly used in melanoma diagnosis and can capture detailed features of a lesion. A great variability exists in the visual appearance of pigmented skin lesions. Therefore, in order to minimize the diagnostic errors that result from the difficulty and subjectivity of visual interpretation, an automatic detection approach is required. The objectives of this paper were to propose a hybrid method using random forest and Gabor wavelet transformation to accurately differentiate which part belong to lesion area and the other is not in a dermoscopy photographs and analyze segmentation accuracy. A random forest classifier consisting of a set of decision trees was used for classification. Gabor wavelets transformation are the mathematical model of visual cortical cells of mammalian brain and an image can be decomposed into multiple scales and multiple orientations by using it. The Gabor function has been recognized as a very useful tool in texture analysis, due to its optimal localization properties in both spatial and frequency domain. Texture features based on Gabor wavelets transformation are found by the Gabor filtered image. Experiment results indicate the following: (1) the proposed algorithm based on random forest outperformed the-state-of-the-art in pigmented skin lesions detection (2) and the inclusion of Gabor wavelet transformation based texture features improved segmentation accuracy significantly.

  17. 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.

  18. Optical properties of mice skin for optical therapy relevant wavelengths: influence of gender and pigmentation

    NASA Astrophysics Data System (ADS)

    Sabino, C. P.; Deana, A. M.; Silva, D. F. T.; França, C. M.; Yoshimura, T. M.; Ribeiro, M. S.

    2015-03-01

    Red and near-infrared light have been widely employed in optical therapies. Skin is the most common optical barrier in non-invasive techniques and in many cases it is the target tissue itself. Consequently, to optimize the outcomes brought by lightbased therapies, the optical properties of skin tissue must be very well elucidated. In the present study, we evaluated the dorsal skin optical properties of albino (BALB/c) and pigmented (C57BL/6) mice using the Kubelka-Munk photon transport model. We evaluated samples from male and female young mice of both strains. Analysis was performed for wavelengths at 630, 660, 780, 810 and 905 nm due to their prevalent use in optical therapies, such as low-level light (or laser) and photodynamic therapies. Spectrophotometric measurements of diffuse transmittance and reflectance were performed using a single integrating sphere coupled to a proper spectrophotometer. Statistic analysis was made by two-way ANOVA, with Tukey as post-test and Levenne and Shapiro-Wilks as pre-tests. Statistical significance was considered when p<0.05. Our results show only a slight transmittance increment (<10 %) as wavelengths are increased from 630 to 905 nm, and no statistical significance was observed. Albino male mice present reduced transmittance levels for all wavelengths. The organization and abundance of skin composing tissues significantly influence its scattering optical properties although absorption remains constant. We conclude that factors such as subcutaneous adiposity and connective tissue structure can have statistically significant influence on mice skin optical properties and these factors have relevant variations among different gender and strains.

  19. [Pigmentation abnormalities in the course of topical immunotherapy of alopecia areata].

    PubMed

    Valsecchi, R; Pansera, B; Rossi, A; Cainelli, T

    1989-01-01

    Pigmentation troubles have been associated in the past years with contact dermatitis and patch-testing. Contact allergy and increase of pigmentation has been associated with Tinopal; on the other hand contact allergy and depigmentation have been associated with many substances such as DNCB, squaric acid dibutylester (SADBE), carbyne, alstroemeria. Leukoderma can also be produced by irritant compound such as phenols, catechols and mercaptoamines. During 1978 and 1984 we have treated 132 patients suffering from alopecia areata with DNCB or SADBE: 51 patients have been treated by DNCB and 81 by SADBE. During the treatment 10 patients developed a leukoderma vitiligo-like localized to the areas of topical application of the allergens and to the flare-up site; one patient had an increase of pigmentation. Lesions vitiligo-like appeared 10-15 weeks after the onset of treatment. Among the patients who developed leukoderma, 4 had a personal history of vitiligo. The possible pathogenetic mechanisms are discussed.

  20. DOSE-RESPONSE FOR UV-INDUCED IMMUNE SUPPRESSION IN PEOPLE OF COLOR: DIFFERENCES BASED ON ERYTHEMAL REACTIVITY RATHER THAN SKIN PIGMENTATION

    EPA Science Inventory

    Ultraviolet radiation (UVR) is known to suppress immune responses in human subjects. The purpose of this study was to develop dose responses across a broad range of skin pigmentation in order to facilitate risk assessment. UVR was administered using FS 20 bulbs. Skin pigmentation...

  1. Comments on "A new algorithm for border description of polarized light surface microscopic images of pigmented skin lesions".

    PubMed

    Burroni, Marco; Alparone, Luciano; Argenti, Fabrizio

    2006-12-01

    In this paper, discrepancies and reference inaccuracies in the paper (Grana et al., 2003) are pointed out. Specifically, it is demonstrated that the definitions of "lesion gradient" and "skin lesion gradient," widely used in a number of medical papers on computer analysis of pigmented skin lesions, are unambiguous, and that the "new algorithm for border description" described in the subject paper substantially relies on well-established concepts dating back over one decade ago.

  2. Sensations of skin infestation linked to abnormal frontolimbic brain reactivity and differences in self-representation.

    PubMed

    Eccles, J A; Garfinkel, S N; Harrison, N A; Ward, J; Taylor, R E; Bewley, A P; Critchley, H D

    2015-10-01

    Some patients experience skin sensations of infestation and contamination that are elusive to proximate dermatological explanation. We undertook a functional magnetic resonance imaging study of the brain to demonstrate, for the first time, that central processing of infestation-relevant stimuli is altered in patients with such abnormal skin sensations. We show differences in neural activity within amygdala, insula, middle temporal lobe and frontal cortices. Patients also demonstrated altered measures of self-representation, with poorer sensitivity to internal bodily (interoceptive) signals and greater susceptibility to take on an illusion of body ownership: the rubber hand illusion. Together, these findings highlight a potential model for the maintenance of abnormal skin sensations, encompassing heightened threat processing within amygdala, increased salience of skin representations within insula and compromised prefrontal capacity for self-regulation and appraisal.

  3. Abnormal lymphocyte response to ultraviolet radiation in multiple skin cancer

    SciTech Connect

    Munch-Petersen, B.; Frentz, G.; Squire, B.; Wallevik, K.; Horn, C.C.; Reymann, F.; Faber, M. )

    1985-06-01

    The lymphocyte response to ultraviolet radiation (254 nm) was investigated by two different methods in 29 unselected patients with multiple epidermal cancer. The ultraviolet-induced DNA synthesis was determined as the increase in incorporation of (/sup 3/H)thymidine in irradiated cells compared with non-irradiated cells after incubation for 2 h. The ultraviolet tolerance was measured as the ultraviolet dose necessary for 50% reduction in phytohemagglutinin-stimulated lymphocyte proliferation. Patients with both squamous cell differentiated tumours and basal cell carcinomas had very high ultraviolet-induced DNA synthesis values. The ultraviolet tolerance in patient lymphocytes was considerably lower than in control lymphocytes with the lowest values occurring in patients with clinical sun intolerance. These investigations may be of predictive value in skin carcinogenesis.

  4. Clinical application of versapulse laser in the treatment of skin pigmentation diseases

    NASA Astrophysics Data System (ADS)

    Liu, Chun-Li; Yuan, Wai-Hua; Yuan, Wei-Wei; Fu, Qiang

    1998-11-01

    387 cases of various skin pigmentous diseases were treated by Versapulse 'C' laser in our department Versapulse 'C' laser consist of 4 kinds of laser with wavelength of VP532nm, Q532nrn, Q755nm, Q1064nm. The vascular lesions, prot wine strain, cherry angioma, strawberry nevus, perckles, solar lentigines, melasma and junctional moles were treated by VP532 or Q532 laser; the nevus of Ota and tattoo were treated by Q755 or Q1064 laser. Satisfactory results were obtained in this paper, we also discussed the therapeutic and the main points of varying diseases with varying laser of wavelength, the use of FMLA anesthesia, controlled cold therapy an the physical protection to laser.

  5. Potential skin involvement in ALS: revisiting Charcot's observation - a review of skin abnormalities in ALS.

    PubMed

    Paré, Bastien; Gros-Louis, François

    2017-03-25

    Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease affecting motor neurons of the brain and spinal cord, leading to progressive paralysis and death. Interestingly, many skin changes have been reported in ALS patients, but never as yet fully explained. These observations could be due to the common embryonic origin of the skin and neural tissue known as the ectodermal germ layer. Following the first observation in ALS patients' skin by Dr Charcot in the 19th century, in the absence of bedsores unlike other bedridden patients, other morphological and molecular changes have been observed. Thus, the skin could be of interest in the study of ALS and other neurodegenerative diseases. This review summarizes skin changes reported in the literature over the years and discusses about a novel in vitro ALS tissue-engineered skin model, derived from patients, for the study of ALS.

  6. Near infrared spectroscopy evaluation of bladder function: the impact of skin pigmentation on detection of physiologic change during voiding

    NASA Astrophysics Data System (ADS)

    Shadgan, Babak; Stothers, Lynn; Molavi, Behnam; Mutabazi, Sharif; Mukisa, Ronald; Macnab, Andrew

    2015-02-01

    Background: Prior research indicates the epidermal pigment layer of human skin (Melanin) has a significant absorption coefficient in the near infra-red (NIR) region; hence attenuation of light in vivo is a potential confounder for NIR spectroscopy (NIRS). A NIRS method developed for transcutaneous evaluation of bladder function is being investigated as a means of improving the burden of bladder disease in sub-Saharan Africa. This required development of a simple wireless NIRS device suitable for use as a screening tool in patients with pigmented skin where the NIR light emitted would penetrate through the epidermal pigment layer and return in sufficient quantity to provide effective monitoring. Methods: Two healthy subjects, one with pigmented skin and one with fair skin, were monitored as they voided spontaneously using the prototype transcutaneous NIRS device positioned over the bladder. The device was a self-contained wireless unit with light emitting diodes (wavelengths 760 and 850 nanometres) and interoptode distance of 4cm. The raw optical data were transmitted to a laptop where graphs of chromophore change were generated with proprietary software and compared between the subjects and with prior data from asymptomatic subjects. Results: Serial monitoring was successful in both subjects. Voiding volumes varied between 350 and 380 cc. In each subject the patterns of chromophore change, trend and magnitude of change were similar and matched the physiologic increase in total and oxygenated hemoglobin recognized to occur in normal bladder contraction during voiding. Conclusions: Skin pigmentation does not compromise the ability of transcutaneous NIRS to interrogate physiologic change in the bladder during bladder contraction in healthy subjects.

  7. The etiology and molecular genetics of human pigmentation disorders

    PubMed Central

    Baxter, Laura L.; Pavan, William J.

    2012-01-01

    Pigmentation, defined as the placement of pigment in skin, hair, and eyes for coloration, is distinctive because the location, amount, and type of pigmentation provides a visual manifestation of genetic heterogeneity in pathways regulating the pigment-producing cells, melanocytes. The scope of this genetic heterogeneity in humans ranges from normal to pathological pigmentation phenotypes. Clinically normal human pigmentation encompasses a variety of skin and hair color as well as with punctate pigmentation such as melanocytic nevi (moles) or ephelides (freckles), while clinically abnormal human pigmentation exhibits markedly reduced or increased pigment levels, known as hypopigmentation and hyperpigmentation, respectively. Elucidation of the molecular genetics underlying pigmentation has revealed genes important for melanocyte development and function. Furthermore, many pigmentation disorders show additional defects in cells other than melanocytes, and identification of the genetic insults in these disorders has revealed pleiotropic genes, where a single gene is required for various functions, often in different cell types. Thus unravelling the genetics of easily visualized pigmentation disorders has identified molecular similarities between melanocytes and less visible cell types/tissues, revealing a common cellular origin and/or common genetic regulatory pathways. Herein we discuss notable human pigmentation disorders and their associated genetic alterations, focusing on the fact that the developmental genetics of pigmentation abnormalities is instructive for understanding normal pathways governing development and function of melanocytes. PMID:23799582

  8. Developing handheld real time multispectral imager to clinically detect erythema in darkly pigmented skin

    NASA Astrophysics Data System (ADS)

    Kong, Linghua; Sprigle, Stephen; Yi, Dingrong; Wang, Fengtao; Wang, Chao; Liu, Fuhan

    2010-02-01

    Pressure ulcers have been identified as a public health concern by the US government through the Healthy People 2010 initiative and the National Quality Forum (NQF). Currently, no tools are available to assist clinicians in erythema, i.e. the early stage pressure ulcer detection. The results from our previous research (supported by NIH grant) indicate that erythema in different skin tones can be identified using a set of wavelengths 540, 577, 650 and 970nm. This paper will report our recent work which is developing a handheld, point-of-care, clinicallyviable and affordable, real time multispectral imager to detect erythema in persons with darkly pigmented skin. Instead of using traditional filters, e.g. filter wheels, generalized Lyot filter, electrical tunable filter or the methods of dispersing light, e.g. optic-acoustic crystal, a novel custom filter mosaic has been successfully designed and fabricated using lithography and vacuum multi layer film technologies. The filter has been integrated with CMOS and CCD sensors. The filter incorporates four or more different wavelengths within the visual to nearinfrared range each having a narrow bandwidth of 30nm or less. Single wavelength area is chosen as 20.8μx 20.8μ. The filter can be deposited on regular optical glass as substrate or directly on a CMOS and CCD imaging sensor. This design permits a multi-spectral image to be acquired in a single exposure, thereby providing overwhelming convenience in multi spectral imaging acquisition.

  9. Diet explains interpopulation variation of plasma carotenoids and skin pigmentation in nestling white storks.

    PubMed

    Negro, J J; Tella, J L; Blanco, G; Forero, M G; Garrido-Fernández, J

    2000-01-01

    Carotenoids have a dietary origin in birds, but mechanisms by which they are absorbed in the gut, transported in the blood, metabolized at various sites, and deposited in the integument remain poorly understood. Variation in both plasma carotenoid levels and external color may reflect different access to dietary carotenoids or individual physiological differences in the uptake and deposition of carotenoids. We compared total plasma carotenoid concentration in nestling white storks (Ciconia ciconia) from 11 Spanish colonies in two consecutive years. The main food item in one of the colonies was the red swamp crayfish (Procambarus clarkii), a recently introduced species. Storks in the remaining colonies ate a variety of foods but no crayfish. Total plasma carotenoid levels in the colony where crayfish were consumed were about five times higher than in any other colony. These differences were maintained after controlling for the significant interyear variability, as well as for sex, age, and body mass of birds. Skin pigmentation also differed, being intensely orange in storks that consumed crayfish but white (unpigmented) in the remaining individuals. With thin-layer chromatography (TLC) and electronic absorption spectroscopy, astaxanthin was confirmed as the major carotenoid in crayfish as well as in the plasma, skin, and body fat of crayfish-eating storks, whereas lutein was the main carotenoid in plasma samples from the other colonies. These results indicate that a newly available carotenoid in the environment, astaxanthin, can be absorbed in large quantities from the gut and be transported in the blood before deposition in different tissues.

  10. Genetic Ancestry, Skin Reflectance and Pigmentation Genotypes in Association with Serum Vitamin D Metabolite Balance

    PubMed Central

    Wilson, Robin Taylor; Roff, Alanna N.; Dai, P. Jenny; Fortugno, Tracey; Douds, Jonathan; Chen, Gang; Grove, Gary L.; Nikiforova, Sheila Ongeri; Barnholtz-Sloan, Jill; Frudakis, Tony; Chinchilli, Vernon M.; Hartman, Terryl J.; Demers, Laurence M.; Shriver, Mark D.; Canfield, Victor A.; Cheng, Keith C.

    2012-01-01

    Background Lower serum vitamin D (25(OH)D) among individuals with African ancestry is attributed primarily to skin pigmentation. However, the influence of genetic polymorphisms controlling for skin melanin content has not been investigated. Therefore, we investigated differences in non-summer serum vitamin D metabolites according to self-reported race, genetic ancestry, skin reflectance and key pigmentation genes (SLC45A2 and SLC24A5). Materials and Methods Healthy individuals reporting at least half African American or half European American heritage were frequency matched to one another on age (+/− 2 years) and sex. 176 autosomal ancestry informative markers were used to estimate genetic ancestry. Melanin index was measured by reflectance spectrometry. Serum vitamin D metabolites (25(OH)D3, 25(OH)D2 and 24,25(OH)2D3) were determined by high performance liquid chromatography (HPLC) tandem mass spectrometry. Percent 24,25(OH)2D3 was calculated as a percent of the parent metabolite (25(OH)D3). Stepwise and backward selection regression models were used to identify leading covariates. Results Fifty African Americans and 50 European Americans participated in the study. Compared with SLC24A5 111Thr homozygotes, individuals with the SLC24A5 111Thr/Ala and 111Ala/Ala genotypes had respectively lower levels of 25(OH)D3 (23.0 and 23.8 nmol/L lower, p-dominant=0.007), and percent 24,25(OH)2D3 (4.1 and 5.2 percent lower, p-dominant=0.003), controlling for tanning bed use, vitamin D/fish oil supplement intake, race/ethnicity, and genetic ancestry. Results were similar with melanin index adjustment, and were not confounded by glucocorticoid, oral contraceptive, or statin use. Conclusions The SLC24A5 111Ala allele was associated with lower serum vitamin 25(OH)D3 and lower percent 24,25(OH)2D3, independently from melanin index and West African genetic ancestry. PMID:23525585

  11. The genetics of skin, hair, and eye color variation and its relevance to forensic pigmentation predictive tests.

    PubMed

    Maroñas, O; Söchtig, J; Ruiz, Y; Phillips, C; Carracedo, Á; Lareu, M V

    2015-01-01

    This review examines the potential application of single nucleotide polymorphism (SNP)-based predictive tests for skin, hair, and eye color to forensic analysis in support of police investigations lacking DNA database matches or eyewitness testimony. Brief descriptions of the biology of melanogenesis and the main genes involved are presented in order to understand the basis of common pigmentation variation in humans. We outline the most recently developed forensically sensitive multiplex tests that can be applied to investigative analyses. The review also describes the biology of the SNPs with the closest associations to, and therefore the best predictors for, common variation in eye, hair, and skin pigmentation. Because pigmentation pathways are complex in their patterns, many of the better-studied human albinism traits provide insight into how pigmentation SNPs interact, control, or modify gene expression and show varying degrees of association with the key genes identified to date. These aspects of SNP action are discussed in an overview of each of the functional groups of pigmentation genes.

  12. PSO-based methods for medical image registration and change assessment of pigmented skin

    NASA Astrophysics Data System (ADS)

    Kacenjar, Steve; Zook, Matthew; Balint, Michael

    2011-03-01

    There are various scientific and technological areas in which it is imperative to rapidly detect and quantify changes in imagery over time. In fields such as earth remote sensing, aerospace systems, and medical imaging, searching for timedependent, regional changes across deformable topographies is complicated by varying camera acquisition geometries, lighting environments, background clutter conditions, and occlusion. Under these constantly-fluctuating conditions, the use of standard, rigid-body registration approaches often fail to provide sufficient fidelity to overlay image scenes together. This is problematic because incorrect assessments of the underlying changes of high-level topography can result in systematic errors in the quantification and classification of interested areas. For example, in the current naked-eye detection strategies of melanoma, a dermatologist often uses static morphological attributes to identify suspicious skin lesions for biopsy. This approach does not incorporate temporal changes which suggest malignant degeneration. By performing the co-registration of time-separated skin imagery, a dermatologist may more effectively detect and identify early morphological changes in pigmented lesions; enabling the physician to detect cancers at an earlier stage resulting in decreased morbidity and mortality. This paper describes an image processing system which will be used to detect changes in the characteristics of skin lesions over time. The proposed system consists of three main functional elements: 1.) coarse alignment of timesequenced imagery, 2.) refined alignment of local skin topographies, and 3.) assessment of local changes in lesion size. During the coarse alignment process, various approaches can be used to obtain a rough alignment, including: 1.) a manual landmark/intensity-based registration method1, and 2.) several flavors of autonomous optical matched filter methods2. These procedures result in the rough alignment of a patient

  13. Response of pigmented porcine skin (Sus scrofa domestica) to single 3.8-micron laser radiation pulses

    NASA Astrophysics Data System (ADS)

    Bostick, Anthony C.; Johnson, Thomas E.; Randolph, Donald Q.; Winston, Golda C. H.

    2005-04-01

    Background and purpose: The purpose of this study is to determine the impact of melanin on skin response to single 3.8 micron, eight microsecond laser pulses and the difference in lesion formation thresholds for input into laser safety standards. Williams et al., performed a study examining laser tissue interaction from 3.8-micron lasers in lightly pigmented Yorkshire pigs (Sus scrofa domestica). However, studies performed by Eggleston et al comparing pigmented and lightly pigmented skin with human skin found that the Yucatan mini-pig is a superior model for laser skin exposures. Methods: Five Yucatan mini-pigs under general anesthesia were exposed to 3.8 micron laser pulses ranging from 0.8 J/cm2 to 93 J/cm2. Gross examinations were done acutely and 24 hours after laser exposure. Skin biopsies were then collected at various times post exposure, and histologic examinations were conducted. Results: The 24 hour ED50 was determined to be 4.5 J/cm2 with fiducial limits of 6.2 and 2.2 J/cm2. As deposited energy was increased, the lesion presentation ranged from whitening of the epidermis (4 J/cm2) to whitening with inflammatory centers (14 J/cm2), and at the highest energy levels inflammatory areas were replaced with an epidermal ulcerated central area (>21 J/cm2). Conclusion: Preliminary findings suggest pigmentation or melanin may play a minor role in the mechanism of laser-tissue damage. The ED50 of Yorkshire pigs was 2.6 J/cm2. The ED50 of the Yucatan mini-pig was found to be 3.6 J/cm2, and although it was higher, it is still within the 95% fiducial limits.

  14. Acerola (Malpighia emarginata DC.) Juice Intake Suppresses UVB-Induced Skin Pigmentation in SMP30/GNL Knockout Hairless Mice

    PubMed Central

    Sato, Yasunori; Uchida, Eriko; Aoki, Hitoshi; Hanamura, Takayuki; Nagamine, Kenichi; Kato, Hisanori; Koizumi, Takeshi

    2017-01-01

    Background/Aims Acerola (Malpighia emarginata DC.) is a fruit that is known to contain high amounts of ascorbic acid (AA) and various phytochemicals. We have previously reported that AA deficiency leads to ultraviolet B (UVB)-induced skin pigmentation in senescence marker protein 30 (SMP30)/gluconolactonase (GNL) knockout (KO) hairless mice. The present study was undertaken to investigate the effects of acerola juice (AJ) intake on the skin of UVB-irradiated SMP30/GNL KO mice. Research design/Principal findings Five-week old hairless mice were given drinking water containing physiologically sufficient AA (1.5 g/L) [AA (+)], no AA [AA (-)] or 1.67% acerola juice [AJ]. All mice were exposed to UVB irradiation for 6 weeks. UVB irradiation was performed three times per week. The dorsal skin color and stratum corneum water content were measured every weekly, and finally, the AA contents of the skin was determined. The skin AA and stratum corneum water content was similar between the AA (+) and AJ groups. The L* value of the AA (+) group was significantly decreased by UVB irradiation, whereas AJ intake suppressed the decrease in the L* value throughout the experiment. Moreover, in the AJ group, there was a significant decrease in the expression level of dopachrome tautomerase, an enzyme that is involved in melanin biosynthesis. Conclusion These results indicate that AJ intake is effective in suppressing UVB-induced skin pigmentation by inhibiting melanogenesis-related genes. PMID:28114343

  15. Direct evidence for positive selection of skin, hair, and eye pigmentation in Europeans during the last 5,000 y

    PubMed Central

    Wilde, Sandra; Timpson, Adrian; Kirsanow, Karola; Kaiser, Elke; Kayser, Manfred; Unterländer, Martina; Hollfelder, Nina; Potekhina, Inna D.; Schier, Wolfram; Thomas, Mark G.; Burger, Joachim

    2014-01-01

    Pigmentation is a polygenic trait encompassing some of the most visible phenotypic variation observed in humans. Here we present direct estimates of selection acting on functional alleles in three key genes known to be involved in human pigmentation pathways—HERC2, SLC45A2, and TYR—using allele frequency estimates from Eneolithic, Bronze Age, and modern Eastern European samples and forward simulations. Neutrality was overwhelmingly rejected for all alleles studied, with point estimates of selection ranging from around 2–10% per generation. Our results provide direct evidence that strong selection favoring lighter skin, hair, and eye pigmentation has been operating in European populations over the last 5,000 y. PMID:24616518

  16. The Taylor Hyperpigmentation Scale: a new visual assessment tool for the evaluation of skin color and pigmentation.

    PubMed

    Taylor, Susan C; Arsonnaud, Stéphanie; Czernielewski, Janusz

    2005-10-01

    The Taylor Hyperpigmentation Scale is a new visual scale developed to provide an inexpensive and convenient method to assess skin color and monitor the improvement of hyperpigmentation following therapy. The tool consists of 15 uniquely colored plastic cards spanning the full range of skin hues and is applicable to individuals with Fitzpatrick skin types I to VI. Each card contains 10 bands of increasingly darker gradations of skin hue that represent progressive levels of hyperpigmentation. This article describes the ongoing development of the Taylor Hyperpigmentation Scale and reports the results of a recent validation study of the use of this newly developed chart in individuals with skin of color. In the study, skin color and an area of hyperpigmentation in 30 subjects of white, African American, Asian, or Hispanic ancestry (approximately 5 from each of the 6 skin types) were evaluated by 10 investigators. The results of the study revealed significant variation among intraindividual and interindividual ratings by investigators of skin hue (P < .0001) and hyperpigmentation (P = .0008); however, most investigators rated the scale as useful and easy to use, and 60% stated they would use it in clinical practice to document the response of hyperpigmentation to therapeutic agents. A heuristic evaluation of the results of this study provided insight into essential considerations for the continued effort to develop a useful and simple scale for assessing skin color and pigmentation.

  17. Understanding visual search patterns of dermatologists assessing pigmented skin lesions before and after online training.

    PubMed

    Krupinski, Elizabeth A; Chao, Joseph; Hofmann-Wellenhof, Rainer; Morrison, Lynne; Curiel-Lewandrowski, Clara

    2014-12-01

    The goal of this investigation was to explore the feasibility of characterizing the visual search characteristics of dermatologists evaluating images corresponding to single pigmented skin lesions (PSLs) (close-ups and dermoscopy) as a venue to improve training programs for dermoscopy. Two Board-certified dermatologists and two dermatology residents participated in a phased study. In phase I, they viewed a series of 20 PSL cases ranging from benign nevi to melanoma. The close-up and dermoscopy images of the PSL were evaluated sequentially and rated individually as benign or malignant, while eye position was recorded. Subsequently, the participating subjects completed an online dermoscopy training module that included a pre- and post-test assessing their dermoscopy skills (phase 2). Three months later, the subjects repeated their assessment on the 20 PSLs presented during phase I of the study. Significant differences in viewing time and eye-position parameters were observed as a function of level of expertise. Dermatologists overall have more efficient search than residents generating fewer fixations with shorter dwells. Fixations and dwells associated with decisions changing from benign to malignant or vice versa from photo to dermatoscopic viewing were longer than any other decision, indicating increased visual processing for those decisions. These differences in visual search may have implications for developing tools to teach dermatologists and residents about how to better utilize dermoscopy in clinical practice.

  18. The eminent dermatologist Moriz Kaposi (1837-1902) and the first description of idiopathic multiple pigmented sarcoma of the skin.

    PubMed

    Karamanou, M; Antoniou, C; Stratigos, A J; Saridaki, Z; Androutsos, G

    2013-01-01

    In 1872, the Hungarian born dermatologist Moriz Kaposi that was practicing in Vienna first described a rare endemic disease that bears his name, among elderly persons of Central European or Mediterranean origin named "idiopathic multiple pigmented sarcoma of the skin". Ten years later the Italian dermatologist Tommaso de Amicis confirms Kaposi's findings. For more than a century the disease was known as a rare low grade malignancy till the 1980s AIDS epidemic.

  19. Reduction of facial pigmentation of melasma by topical lignin peroxidase: A novel fast-acting skin-lightening agent

    PubMed Central

    ZHONG, SHAO-MIN; SUN, NAN; LIU, HUI-XIAN; NIU, YUE-QING; WU, YAN

    2015-01-01

    The aim of the present study was to evaluate the efficacy and safety of lignin peroxidase (LIP) as a skin-lightening agent in patients with melasma. A self-controlled clinical study was performed in 31 women who had melasma on both sides of the face. This study involved 8 weeks of a full-face product treatment. The skin color was measured at days 0, 7, 28 and 56 using a chromameter on the forehead and cheeks. Standardized digital photographic images of each side of the face of all subjects were captured by a complexion analysis system. Clinical scores of the pigmentation were determined by two dermatologists. After using the LIP whitening lotion for 7 days, the luminance (L*) values of the melasma and the normal skin were significantly increased from baseline. The L* values continued to increase at days 28 and 56. The melasma area severity index (MASI) score was statistically decreased after 28 days of treatment. No treatment-related adverse events were observed. LIP whitening lotion was able to eliminate the skin pigmentation after 7 days of treatment, and provides a completely innovative approach to rapid skin lightening. The LIP whitening lotion exhibited good compatibility and was well tolerated. PMID:25574195

  20. Inhibition of skin pigmentation by an extract of Lepidium apetalum and its possible implication in IL-6 mediated signaling.

    PubMed

    Choi, Hyunjung; Ahn, Soomi; Lee, Byeong G; Chang, Ihseop; Hwang, Jae S

    2005-12-01

    The development of effective skin-lightening agents is an increasingly important area of research aimed at the treatment of hyperpigmentation induced by UV irradiation or by medical conditions such as melasma, postinflammatory melanoderma and solar lentigo. Although some inhibit tyrosinase, identifying and understanding the mechanisms of action of other agents is an important goal if more effective pigmentation inhibitors are to be developed. We present here that an extract of Lepidium apetalum (ELA) decreased UV-induced skin pigmentation in brown guinea pigs and melanogenesis of HM3KO human melanoma cells. Interestingly, ELA did not reduce melanogenesis in HM3KO cells unless they were co-cultivated in keratinocyte-conditioned medium prepared by culturing keratinocytes with ELA. Under these conditions, ELA decreased tyrosinase mRNA and protein expression as well as melanin content via an ELA-mediated increase in keratinocyte IL-6 production which in turn was shown to decrease in the expression Mitf, a transcription factor implicated in tyrosinase gene expression and melanocyte differentiation. The results reveal that ELA may be an effective inhibitor of hyperpigmentation caused by UV irradiation or by pigmented skin disorders through a mechanism involving IL-6-mediated downregulation of Mitf rather than a direct inhibition of tyrosinase activity.

  1. Association of the OCA2 Polymorphism His615Arg with Melanin Content in East Asian Populations: Further Evidence of Convergent Evolution of Skin Pigmentation

    PubMed Central

    Edwards, Melissa; Bigham, Abigail; Tan, Jinze; Li, Shilin; Gozdzik, Agnes; Ross, Kendra; Jin, Li; Parra, Esteban J.

    2010-01-01

    The last decade has witnessed important advances in our understanding of the genetics of pigmentation in European populations, but very little is known about the genes involved in skin pigmentation variation in East Asian populations. Here, we present the results of a study evaluating the association of 10 Single Nucleotide Polymorphisms (SNPs) located within 5 pigmentation candidate genes (OCA2, DCT, ADAM17, ADAMTS20, and TYRP1) with skin pigmentation measured quantitatively in a sample of individuals of East Asian ancestry living in Canada. We show that the non-synonymous polymorphism rs1800414 (His615Arg) located within the OCA2 gene is significantly associated with skin pigmentation in this sample. We replicated this result in an independent sample of Chinese individuals of Han ancestry. This polymorphism is characterized by a derived allele that is present at a high frequency in East Asian populations, but is absent in other population groups. In both samples, individuals with the derived G allele, which codes for the amino acid arginine, show lower melanin levels than those with the ancestral A allele, which codes for the amino acid histidine. An analysis of this non-synonymous polymorphism using several programs to predict potential functional effects provides additional support for the role of this SNP in skin pigmentation variation in East Asian populations. Our results are consistent with previous research indicating that evolution to lightly-pigmented skin occurred, at least in part, independently in Europe and East Asia. PMID:20221248

  2. Abnormalities in itch sensation and skin barrier function in atopic NC/Tnd mice.

    PubMed

    Amagai, Yosuke; Matsuda, Hiroshi; Tanaka, Akane

    2013-01-01

    Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by dryness and itchy skin. Genetic factors as well as other factors, including abnormality in skin barrier function, hypersensitivity of itch sensory nerves, and dysfunction of the immune system, strongly affect the onset and exacerbation of AD. Recently, it has become clear that itch sensation is closely related to pain sensation. By using NC/Tnd mice, a unique spontaneous animal model for human AD, we found abnormalities in sensitivity against external stimuli as compared to two standard strains, BALB/c and B6 mice. Particularly, in conventional NC/Tnd mice with AD, stimulation against transient receptor potential (TRP) V1 reduced the scratching behavior, suggesting the possibility of a TRPV1 modulator in the treatment of atopic itch. The review outlines observations regarding itch sensation and skin barrier function in NC/Tnd mice by using a novel itch quantification system for the laboratory animals, which may bring great progress in the future study of itch.

  3. A Review of the Quantification and Classification of Pigmented Skin Lesions: From Dedicated to Hand-Held Devices.

    PubMed

    Filho, Mercedes; Ma, Zhen; Tavares, João Manuel R S

    2015-11-01

    In recent years, the incidence of skin cancer cases has risen, worldwide, mainly due to the prolonged exposure to harmful ultraviolet radiation. Concurrently, the computer-assisted medical diagnosis of skin cancer has undergone major advances, through an improvement in the instrument and detection technology, and the development of algorithms to process the information. Moreover, because there has been an increased need to store medical data, for monitoring, comparative and assisted-learning purposes, algorithms for data processing and storage have also become more efficient in handling the increase of data. In addition, the potential use of common mobile devices to register high-resolution images of skin lesions has also fueled the need to create real-time processing algorithms that may provide a likelihood for the development of malignancy. This last possibility allows even non-specialists to monitor and follow-up suspected skin cancer cases. In this review, we present the major steps in the pre-processing, processing and post-processing of skin lesion images, with a particular emphasis on the quantification and classification of pigmented skin lesions. We further review and outline the future challenges for the creation of minimum-feature, automated and real-time algorithms for the detection of skin cancer from images acquired via common mobile devices.

  4. Investigation of emtricitabine-associated skin pigmentation and safety in HIV-1-infected Japanese patients.

    PubMed

    Shirasaka, Takuma; Tadokoro, Taketsugu; Yamamoto, Yasuyuki; Fukutake, Katsuyuki; Kato, Yukihiko; Odawara, Takashi; Nakamura, Tetsuya; Ajisawa, Atsushi; Negishi, Masayoshi

    2011-10-01

    Emtricitabine (FTC) has been reported to cause skin pigmentation (SP), and the incidence of SP associated with FTC varied with ethnicity, with a higher rate in African-American patients (8%). We assessed the incidence of SP in Japanese HIV-1-infected patients receiving combination antiretroviral therapy (cART) with FTC for a period of 48 weeks and confirmed new findings of FTC-associated SP, including pathological characteristics. This was a multicenter, prospective, longitudinal non-randomized study. We evaluated the appearance of SP at 48 weeks as the primary endpoint in 155 Japanese patients, and secondary endpoints included the characteristics of the SP (location, color tone, size, and progression). Six cases (3.9%) of SP occurred at a median of 124 days (range: 7-259 days) within 48 weeks. The SP looked like an isolated dark spot, 1-2 mm in diameter, mainly on the hands and/or feet. The severity of all the SPs was mild. Each SP had disappeared or faded at a median of 112 days (range: 28-315 days) with continued FTC. FTC-associated SP was considered to be lentigo simplex by dermatoscopy and pathological appearance. In summary, the incidence of FTC-associated SP in Japanese patients was 3.9%, and was comparable to the previously reported incidence in Asian patients (4%). FTC-associated SP was not associated with any clinically significant symptoms and has little clinical significance.

  5. Photobleaching measurements of pigmented and vascular skin lesions: results of a clinical trial

    NASA Astrophysics Data System (ADS)

    Lihachev, Alexey; Rozniece, Kristine; Lesins, Janis; Spigulis, Janis

    2011-07-01

    The autofluorescence photobleaching intensity dynamics of in vivo skin and skin pathologies under continuous 532 nm laser irradiation have been studied. Overall the 141 human skin malformations were investigated by laser induced skin autofluorescence photobleaching analysis. Details of equipment are described along with some measurement results illustrating potentiality of the technology.

  6. Cisplatin in children: hearing loss correlates with iris and skin pigmentation.

    PubMed

    Todd, N W; Alvarado, C S; Brewer, D B

    1995-10-01

    Pigmentation is reported to affect cisplatin-induced ototoxicity in adult humans. The hearing loss is worse in people with brown irises, than in those with blue irises. We assessed the hypothesis that cisplatin-treated children with dark irises suffer more deterioration in auditory thresholds than do those with less pigmentation. For the 19 children whose data met the requirements of this observational retrospective study, we found a weak correlation (Spearman's r = 0.50; p < 0.05) of high frequency hearing loss (at 4000 Hz) and pigmentation. Blue or hazel-eyed children averaged 2.9 dB worsening at 4000 Hz, in contrast to 14.2 dB worsening for brown or black-eyed children. Pigmentation may account for some of the individual susceptibility to cisplatin ototoxicity. We suggest that iris colour be included in future reports of cisplatin-related hearing loss.

  7. Optical configuration of pigmented lesion detection by frequency analysis of skin speckle patterns

    PubMed Central

    Bishitz, Yael; Ozana, Nisan; Schwarz, Ariel; Beiderman, Yevgeny; Garcia, Javier; Zalevsky, Zeev

    2016-01-01

    In this paper we present a novel approach of realizing a safe, simple, and inexpensive sensor applicable to pigmented lesions detection. The approach is based on temporal tracking of back-reflected secondary speckle patterns generated while illuminating the affected area with a laser and applying periodic pressure to the surface via a controlled vibration source. When applied to pigmented lesions, the technique is superior to visual examination in avoiding many false positives and resultant unnecessary biopsies. Applying a series of different vibration frequencies at the examined tissue and analyzing the 2-D time varying speckle patterns in response to the applied periodic pressure creates a unique signature for each and different pigmented lesion. Analyzing these signatures is the first step toward detection of malignant melanoma. In this paper we present preliminary experiments that show the validity of the developed sensor for the classification of pigmented lesions. PMID:27231603

  8. Flat pigmented macules on sun-damaged skin of the head/neck: junctional nevus, atypical lentiginous nevus, or melanoma in situ?

    PubMed

    Zalaudek, Iris; Cota, Carlo; Ferrara, Gerardo; Moscarella, Elvira; Guitera, Pascale; Longo, Caterina; Piana, Simonetta; Argenziano, Giuseppe

    2014-01-01

    The clinical recognition of lentigo maligna (LM) in the mottled chronic sun-damaged skin can be challenging, because it shares many clinical features with other pigmented macules that commonly arise on sun-damaged skin. These include solar lentigo, flat seborrheic keratosis, and pigmented actinic keratosis, but almost never "nevus." The reason nevus is not included in the differential diagnosis of LM can be explained by the fact that the stereotypical appearance of a facial nevus differs remarkably from that of an LM. Facial nevi in adults are usually nodular, dome-shaped, well-defined, and hypopigmented (i.e., intradermal nevus of the Miescher type), whereas LM typically appears as a flat, ill-defined, and pigmented macule. Although this concept based on clinical observations sounds reasonable, clinicians apply it often only unconsciously and accept a given histopathologic diagnosis of a "junctional or lentiginous nevus" of a flat pigmented facial macule without the necessary criticism about its clinicopathologic validity.

  9. Is pigment patterning in fish skin determined by the Turing mechanism?

    PubMed

    Watanabe, Masakatsu; Kondo, Shigeru

    2015-02-01

    More than half a century ago, Alan Turing postulated that pigment patterns may arise from a mechanism that could be mathematically modeled based on the diffusion of two substances that interact with each other. Over the past 15 years, the molecular and genetic tools to verify this prediction have become available. Here, we review experimental studies aimed at identifying the mechanism underlying pigment pattern formation in zebrafish. Extensive molecular genetic studies in this model organism have revealed the interactions between the pigment cells that are responsible for the patterns. The mechanism discovered is substantially different from that predicted by the mathematical model, but it retains the property of 'local activation and long-range inhibition', a necessary condition for Turing pattern formation. Although some of the molecular details of pattern formation remain to be elucidated, current evidence confirms that the underlying mechanism is mathematically equivalent to the Turing mechanism.

  10. Dermoscopic and Clinical Features of Pigmented Skin Lesions of the Genital Area*

    PubMed Central

    Cengiz, Fatma Pelin; Emiroglu, Nazan; Wellenhof, Rainer Hofmann

    2015-01-01

    BACKGROUND The dermoscopic features of vulvar melanosis lesions are well known. To our knowledge, there are only a few case reports about dermoscopic features of pigmented genital lesions in male patients. OBJECTIVE To evaluate dermoscopic and clinical characteristics of benign lesions of the genital area in both males and females, and to assess the distinguishing dermoscopic criteria of vulvar melanosis and atypical melanocytic nevi of the genital type. METHODS 68 patients with pigmented genital lesions were included in this observational study (28 male and 40 female). A punch biopsy was taken from all pigmented lesions and histopathological examination was performed on all specimens. RESULTS We histopathologically diagnosed: genital melanosis in 40 lesions, atypical melanocytic nevi of the genital type in 15 lesions, melanocytic nevi in 9 lesions, seborrheic keratosis in 4 lesions. The most frequent locations were the glans penis (19 patients, 67.9%) in males and the labia minora (19 patients, 47.5%) in females. The mean age of patients with atypical nevi (28,6 ± 11,36) was significantly lower than the mean age of patients with genital melanosis (47,07 ± 15,33). CONCLUSIONS Parallel pattern is prominent in genital melanosis, ring-like pattern is only observed in genital melanosis. Most pigmented lesions on the genital area are solitary. Blue-white veil and irregular dots are only observed in AMNGT. According to these results, we propose that histopathological examination is performed, especially if blue-white veil and irregular dots are found by dermoscopy. PMID:25830986

  11. Modulation of Abnormal Metabolic Brain Networks by Experimental Therapies in a Nonhuman Primate Model of Parkinson Disease: An Application to Human Retinal Pigment Epithelial Cell Implantation.

    PubMed

    Peng, Shichun; Ma, Yilong; Flores, Joseph; Cornfeldt, Michael; Mitrovic, Branka; Eidelberg, David; Doudet, Doris J

    2016-10-01

    Abnormal covariance pattern of regional metabolism associated with Parkinson disease (PD) is modulated by dopaminergic pharmacotherapy. Using high-resolution (18)F-FDG PET and network analysis, we previously derived and validated a parkinsonism-related metabolic pattern (PRP) in nonhuman primate models of PD. It is currently not known whether this network is modulated by experimental therapeutics. In this study, we examined changes in network activity by striatal implantation of human levodopa-producing retinal pigment epithelial (hRPE) cells in parkinsonian macaques and evaluated the reproducibility of network activity in a small test-retest study.

  12. Illuminant color estimation based on pigmentation separation from human skin color

    NASA Astrophysics Data System (ADS)

    Tanaka, Satomi; Kakinuma, Akihiro; Kamijo, Naohiro; Takahashi, Hiroshi; Tsumura, Norimichi

    2015-03-01

    Human has the visual system called "color constancy" that maintains the perceptive colors of same object across various light sources. The effective method of color constancy algorithm was proposed to use the human facial color in a digital color image, however, this method has wrong estimation results by the difference of individual facial colors. In this paper, we present the novel color constancy algorithm based on skin color analysis. The skin color analysis is the method to separate the skin color into the components of melanin, hemoglobin and shading. We use the stationary property of Japanese facial color, and this property is calculated from the components of melanin and hemoglobin. As a result, we achieve to propose the method to use subject's facial color in image and not depend on the individual difference among Japanese facial color.

  13. N-Nicotinoyl dopamine inhibits skin pigmentation by suppressing of melanosome transfer.

    PubMed

    Kim, Bora; Hwang, Jae Sung; Kim, Hyun-Soo

    2015-12-15

    We investigated the inhibitory effects of a niacinamide derivative, N-Nicotinoyl dopamine (NND) on melanogenesis. NND inhibits melanosome transfer in a normal human melanocyte-keratinocyte co-culture system and through phagocytic ability without affecting viability of cells while it did not show inhibitory effects of tyrosinase and melanin synthesis in B16F10 mouse melanoma cells. In addition, safety of NND was verified through performing neural stem cell morphology assay. Our findings indicate that NND may potentially be used for cosmetic industry for improvement of skin whitening and therapies related with several skin disorders, and the effect of NND may be acquired via reduction of melanosome transfer.

  14. Skin pigment anomalies and mosaicism for a double autosomal trisomy (48,XX,+18,+20).

    PubMed

    Devriendt, K; Matthijs, G; Meireleire, J; Roelen, L; van Buggenhout, G; Fryns, J P

    1998-01-01

    We present a patient with profound mental retardation, epilepsy, facial dysmorphism and multiple skin hyper- and depigmentation areas. Karyotype in white blood cells was normal female, whereas in cultured skin fibroblasts originating from a depigmentated area, mosaic 48,XX,+18,+20 was found. Molecular analyses using polymorphic microsatellites showed a different origin of both additional chromosomes: maternal for the chromosome 20, paternal for chromosome 18. This, together with a mosaic state is consistent with a double postzygotic error in chromosome segregation possibly occurring in a single cell division.

  15. A Genome-Wide Association Study Identifies the Skin Color Genes IRF4, MC1R, ASIP, and BNC2 Influencing Facial Pigmented Spots.

    PubMed

    Jacobs, Leonie C; Hamer, Merel A; Gunn, David A; Deelen, Joris; Lall, Jaspal S; van Heemst, Diana; Uh, Hae-Won; Hofman, Albert; Uitterlinden, André G; Griffiths, Christopher E M; Beekman, Marian; Slagboom, P Eline; Kayser, Manfred; Liu, Fan; Nijsten, Tamar

    2015-07-01

    Facial pigmented spots are a common skin aging feature, but genetic predisposition has yet to be thoroughly investigated. We conducted a genome-wide association study for pigmented spots in 2,844 Dutch Europeans from the Rotterdam Study (mean age: 66.9±8.0 years; 47% male). Using semi-automated image analysis of high-resolution digital facial photographs, facial pigmented spots were quantified as the percentage of affected skin area (mean women: 2.0% ±0.9, men: 0.9% ±0.6). We identified genome-wide significant association with pigmented spots at three genetic loci: IRF4 (rs12203592, P=1.8 × 10(-27)), MC1R (compound heterozygosity score, P=2.3 × 10(-24)), and RALY/ASIP (rs6059655, P=1.9 × 10(-9)). In addition, after adjustment for the other three top-associated loci the BNC2 locus demonstrated significant association (rs62543565, P=2.3 × 10(-8)). The association signals observed at all four loci were successfully replicated (P<0.05) in an independent Dutch cohort (Leiden Longevity Study n=599). Although the four genes have previously been associated with skin color variation and skin cancer risk, all association signals remained highly significant (P<2 × 10(-8)) when conditioning the association analyses on skin color. We conclude that genetic variations in IRF4, MC1R, RALY/ASIP, and BNC2 contribute to the acquired amount of facial pigmented spots during aging, through pathways independent of the basal melanin production.

  16. QTL and association analysis for skin and fibre pigmentation in sheep provides evidence of a major causative mutation and epistatic effects.

    PubMed

    Raadsma, H W; Jonas, E; Fleet, M R; Fullard, K; Gongora, J; Cavanagh, C R; Tammen, I; Thomson, P C

    2013-08-01

    The pursuits of white features and white fleeces free of pigmented fibre have been important selection objectives for many sheep breeds. The cause and inheritance of non-white colour patterns in sheep has been studied since the early 19th century. Discovery of genetic causes, especially those which predispose pigmentation in white sheep, may lead to more accurate selection tools for improved apparel wool. This article describes an extended QTL study for 13 skin and fibre pigmentation traits in sheep. A total of 19 highly significant, 10 significant and seven suggestive QTL were identified in a QTL mapping experiment using an Awassi × Merino × Merino backcross sheep population. All QTL on chromosome 2 exceeded a LOD score of greater than 4 (range 4.4-30.1), giving very strong support for a major gene for pigmentation on this chromosome. Evidence of epistatic interactions was found for QTL for four traits on chromosomes 2 and 19. The ovine TYRP1 gene on OAR 2 was sequenced as a strong positional candidate gene. A highly significant association (P < 0.01) of grandparental haplotypes across nine segregating SNP/microsatellite markers including one non-synonymous SNP with pigmentation traits could be shown. Up to 47% of the observed variation in pigmentation was accounted for by models using TYRP1 haplotypes and 83% for models with interactions between two QTL probabilities, offering scope for marker-assisted selection for these traits.

  17. Optical devices used for image analysis of pigmented skin lesions: a proposal for quality assurance protocol using tissue-like phantoms.

    PubMed

    Lualdi, M; Colombo, A; Carrara, M; Scienza, L; Tomatis, S; Marchesini, R

    2006-12-07

    Different technological tools have been developed to aid in the diagnosis of pigmented skin lesions, including cameras working with conventional RGB colour systems, epiluminescence microscopy and spectrophotometric methods using visible and near infrared wavelengths. All the different procedures should provide in an objective and reproducible fashion quantitative measurements of the colour and shape features of a given skin mole. At present, many devices have been introduced in experimental stages for clinical diagnosis, mainly used to provide to the clinicians an objective, computer-assisted second opinion. As for any diagnostic instruments, optical devices should also be subjected to a dedicated quality assurance protocol in order to evaluate the response repeatability of each device (intra-instrument agreement) and to check the accordance among the responses of different devices (inter-instrument agreement). The aim of this study was to design a quality assurance protocol for optical devices dedicated to image analysis of pigmented skin lesions and, in case, to detect cutaneous melanoma by using suitable tissue-like phantoms as standard references that enable testing of both hardware and software components. As an example, we report the results of intra-instrument and inter-instrument agreement when the protocol was applied on a series of 30 SpectroShade instruments, a novel optical device based on multi-spectral image analysis of colour and shape features of pigmented skin lesion.

  18. Pigment cell movement is not required for generation of Turing patterns in zebrafish skin

    PubMed Central

    Bullara, D.; De Decker, Y.

    2015-01-01

    The zebrafish is a model organism for pattern formation in vertebrates. Understanding what drives the formation of its coloured skin motifs could reveal pivotal to comprehend the mechanisms behind morphogenesis. The motifs look and behave like reaction–diffusion Turing patterns, but the nature of the underlying physico-chemical processes is very different, and the origin of the patterns is still unclear. Here we propose a minimal model for such pattern formation based on a regulatory mechanism deduced from experimental observations. This model is able to produce patterns with intrinsic wavelength, closely resembling the experimental ones. We mathematically prove that their origin is a Turing bifurcation occurring despite the absence of cell motion, through an effect that we call differential growth. This mechanism is qualitatively different from the reaction–diffusion originally proposed by Turing, although they both generate the short-range activation and the long-range inhibition required to form Turing patterns. PMID:25959141

  19. Pigment cell movement is not required for generation of Turing patterns in zebrafish skin

    NASA Astrophysics Data System (ADS)

    Bullara, D.; de Decker, Y.

    2015-05-01

    The zebrafish is a model organism for pattern formation in vertebrates. Understanding what drives the formation of its coloured skin motifs could reveal pivotal to comprehend the mechanisms behind morphogenesis. The motifs look and behave like reaction-diffusion Turing patterns, but the nature of the underlying physico-chemical processes is very different, and the origin of the patterns is still unclear. Here we propose a minimal model for such pattern formation based on a regulatory mechanism deduced from experimental observations. This model is able to produce patterns with intrinsic wavelength, closely resembling the experimental ones. We mathematically prove that their origin is a Turing bifurcation occurring despite the absence of cell motion, through an effect that we call differential growth. This mechanism is qualitatively different from the reaction-diffusion originally proposed by Turing, although they both generate the short-range activation and the long-range inhibition required to form Turing patterns.

  20. Prehistological evaluation of benign and malignant pigmented skin lesions with optical computed tomography

    NASA Astrophysics Data System (ADS)

    Kokolakis, Athanasios; Zacharakis, Giannis; Krasagakis, Konstantin; Lasithiotakis, Konstantinos; Favicchio, Rosy; Spiliopoulos, George; Giannikaki, Elpida; Ripoll, Jorge; Tosca, Androniki

    2012-06-01

    Discrimination of benign and malignant melanocytic lesions is a major issue in clinical dermatology. Assessment of the thickness of melanoma is critical for prognosis and treatment selection. We aimed to evaluate a novel optical computed tomography (optical-CT) system as a tool for three-dimensional (3-D) imaging of melanocytic lesions and its ability to discriminate benign from malignant melanocytic lesions while simultaneously determining the thickness of invasive melanoma. Seventeen melanocytic lesions, one hemangioma, and normal skin were assessed immediately after their excision by optical-CT and subsequently underwent histopathological examination. Tomographic reconstructions were performed with a back-propagation algorithm calculating a 3-D map of the total attenuation coefficient (AC). There was a statistically significant difference between melanomas, dysplastic nevi, and non-dysplastic nevi, as indicated by Kruskal-Wallis test. Median AC values were higher for melanomas compared with dysplastic and non-dysplastic nevi. No statistically significant difference was observed when thickness values obtained by optical-CT were compared with histological thickness using a Wilcoxon sighed rank test. Our results suggest that optical-CT can be important for the immediate prehistological evaluation of biopsies, assisting the physician for a rapid assessment of malignancy and of the thickness of a melanocytic lesion.

  1. Routine Clinical-Pathologic Correlation of Pigmented Skin Tumors Can Influence Patient Management

    PubMed Central

    Longo, Caterina; Piana, Simonetta; Lallas, Aimilios; Moscarella, Elvira; Lombardi, Mara; Raucci, Margherita; Pellacani, Giovanni; Argenziano, Giuseppe

    2015-01-01

    Background Several studies have demonstrated the benefit of integrating clinical with pathologic information, to obtain a confident diagnosis for melanocytic tumors. However, all those studies were conducted retrospectively and no data are currently available about the role of a clinical-pathologic correlation approach on a daily basis in clinical practice. Aim of the Study In our study, we evaluated the impact of a routine clinical-pathologic correlation approach for difficult skin tumors seen over 3 years in a tertiary referral center. Results Interestingly, a re-appraisal was requested for 158 out of 2015 (7.7%) excised lesions because clinical-pathologic correlation was missing. Of note, in 0.6% of them (13 out of 2045) the first histologic diagnosis was revised in the light of clinical information that assisted the Pathologist to re-evaluate the histopathologic findings that might be bland or inconspicuous per se. Conclusion In conclusion, our study demonstrated that an integrated approach involving clinicians and pathologists allows improving management of selected patients by shifting from a simply disease-focused management (melanoma versus nevus) to a patient-centered approach. PMID:26325678

  2. Complex Inheritance of Melanoma and Pigmentation of Coat and Skin in Grey Horses

    PubMed Central

    Druml, Thomas; Seltenhammer, Monika; Sundström, Elisabeth; Pielberg, Gerli Rosengren; Andersson, Leif

    2013-01-01

    Abstract The dominant phenotype of greying with age in horses, caused by a 4.6-kb duplication in intron 6 of STX17, is associated with a high incidence of melanoma and vitiligo-like skin depigmentation. However, the progressive greying and the incidence of melanoma, vitiligo-like depigmentation, and amount of speckling in these horses do not follow a simple inheritance pattern. To understand their inheritance, we analysed the melanoma grade, grey level, vitiligo grade, and speckling grade of 1,119 Grey horses (7,146 measurements) measured in six countries over a 9-year period. We estimated narrow sense heritability (h2), and we decomposed this parameter into polygenic heritability (h2 POLY), heritability due to the Grey (STX17) mutation (h2 STX17), and heritability due to agouti (ASIP) locus (h2 ASIP). A high heritability was found for greying (h2 = 0.79), vitiligo (h2 = 0.63), and speckling (h2 = 0.66), while a moderate heritability was estimated for melanoma (h2 = 0.37). The additive component of ASIP was significantly different from zero only for melanoma (h2 ASIP = 0.02). STX17 controlled large proportions of phenotypic variance (h2 STX17 = 0.18–0.55) and overall heritability (h2 STX17/h2 = 0.28–0.83) for all traits. Genetic correlations among traits were estimated as moderate to high, primarily due to the effects of the STX17 locus. Nevertheless, the correlation between progressive greying and vitiligo-like depigmentation remained large even after taking into account the effects of STX17. We presented a model where four traits with complex inheritance patterns are strongly influenced by a single mutation. This is in line with evidence of recent studies in domestic animals indicating that some complex traits are, in addition to the large number of genes with small additive effects, influenced by genes of moderate-to-large effect. Furthermore, we demonstrated that the STX17 mutation explains to a large extent the moderate to high

  3. Genome-wide association studies identify several new loci associated with pigmentation traits and skin cancer risk in European Americans

    PubMed Central

    Zhang, Mingfeng; Song, Fengju; Liang, Liming; Nan, Hongmei; Zhang, Jiangwen; Liu, Hongliang; Wang, Li-E.; Wei, Qingyi; Lee, Jeffrey E.; Amos, Christopher I.; Kraft, Peter; Qureshi, Abrar A.; Han, Jiali

    2013-01-01

    Aiming to identify novel genetic loci for pigmentation and skin cancer, we conducted a series of genome-wide association studies on hair color, eye color, number of sunburns, tanning ability and number of non-melanoma skin cancers (NMSCs) among 10 183 European Americans in the discovery stage and 4504 European Americans in the replication stage (for eye color, 3871 males in the discovery stage and 2496 males in the replication stage). We targeted novel chromosome regions besides the known ones for replication. As a result, we identified a new region downstream of the EDNRB gene on 13q22 associated with hair color and the strongest association was the single-nucleotide polymorphism (SNP) rs975739 (P = 2.4 × 10−14; P = 5.4 × 10−9 in the discovery set and P = 1.2 × 10−6 in the replication set). Using blue, intermediate (including green) and brown eye colors as co-dominant outcomes, we identified the SNP rs3002288 in VASH2 on 1q32.3 associated with brown eye (P = 7.0 × 10−8; P = 5.3 × 10−5 in the discovery set and P = 0.02 in the replication set). Additionally, we identified a significant interaction between the SNPs rs7173419 and rs12913832 in the OCA2 gene region on brown eye color (P-value for interaction = 3.8 × 10−3). As for the number of NMSCs, we identified two independent SNPs on chr6 and one SNP on chromosome 14: rs12203592 in IRF4 (P = 7.2 × 10−14; P = 1.8 × 10−8 in the discovery set and P = 6.7 × 10−7 in the replication set), rs12202284 between IRF4 and EXOC2 (P = 5.0 × 10−8; P = 6.6 × 10−7 in the discovery set and P = 3.0 × 10−3 in the replication set) and rs8015138 upstream of GNG2 (P = 6.6 × 10−8; P = 5.3 × 10−7 in the discovery set and P = 0.01 in the replication set). PMID:23548203

  4. Nicotinic Acid Receptor Abnormalities in Human Skin Cancer: Implications for a Role in Epidermal Differentiation

    PubMed Central

    Bermudez, Yira; Benavente, Claudia A.; Meyer, Ralph G.; Coyle, W. Russell; Jacobson, Myron K.; Jacobson, Elaine L.

    2011-01-01

    Background Chronic UV skin exposure leads to epidermal differentiation defects in humans that can be largely restored by pharmacological doses of nicotinic acid. Nicotinic acid has been identified as a ligand for the human G-protein-coupled receptors GPR109A and GPR109B that signal through Gi-mediated inhibition of adenylyl cyclase. We have examined the expression, cellular distribution, and functionality of GPR109A/B in human skin and skin derived epidermal cells. Results Nicotinic acid increases epidermal differentiation in photodamaged human skin as judged by the terminal differentiation markers caspase 14 and filaggrin. Both GPR109A and GPR109B genes are transcribed in human skin and in epidermal keratinocytes, but expression in dermal fibroblasts is below limits of detection. Receptor transcripts are greatly over-expressed in squamous cell cancers. Receptor protein in normal skin is prominent from the basal through granular layers of the epidermis, with cellular localization more dispersive in the basal layer but predominantly localized at the plasma membrane in more differentiated epidermal layers. In normal human primary and immortalized keratinocytes, nicotinic acid receptors show plasma membrane localization and functional Gi-mediated signaling. In contrast, in a squamous cell carcinoma derived cell line, receptor protein shows a more diffuse cellular localization and the receptors are nearly non-functional. Conclusions The results of these studies justify future genetic and pharmacological intervention studies to define possible specific role(s) of nicotinic acid receptors in human skin homeostasis. PMID:21655214

  5. Melan-a-positive "pseudomelanocytic nests": a pitfall in the histopathologic and immunohistochemical diagnosis of pigmented lesions on sun-damaged skin.

    PubMed

    Beltraminelli, Helmut; Shabrawi-Caelen, Laila El; Kerl, Helmut; Cerroni, Lorenzo

    2009-05-01

    We encountered recently 3 cases with a histopathologic diagnosis of melanoma in situ on sun-damaged skin (male = 2, female = 1; median age: 59 years; range: 52-60 years). The diagnosis was based mainly on the finding of actinic elastosis in the dermis and increased number of melanocytes in the epidermis and was confirmed by strong positivity for Melan-A in single cells and in small nests ("pseudomelanocytic nests"), located at the dermoepidermal junction. Indeed, examination of slides stained with hematoxylin and eosin revealed the presence of marked hyperpigmentation and small nests of partially pigmented cells at the dermoepidermal junction, positive for Melan-A. The histologic and especially the immunohistochemical features were indistinguishable from those of melanoma in situ on chronic sun-damaged skin. In addition, a variably dense lichenoid inflammation was present. Clinicopathologic correlation, however, showed, in all patients, the presence of a lichenoid dermatitis (phototoxic reaction, 1 case; lichen planus pigmentosus, 1 case; and pigmented lichenoid keratosis, 1 case). Our cases clearly show the histopathologic pitfalls represented by lichenoid reactions on chronic sun-damaged skin. Immunohistochemical investigations, especially if performed with Melan-A alone, may lead to confusing and potentially disastrous results. The unexpected staining pattern of Melan-A in cases like ours raises concern about the utility of this antibody in the setting of a lichenoid tissue reaction on chronic sun-damaged skin. It should be underlined that pigmented lesions represent a paradigmatic example of how immunohistochemical results should be interpreted carefully and always in conjunction with histologic and clinical features.

  6. Inhibitory effect of 2-methyl-naphtho[1,2,3-de]quinolin-8-one on melanosome transport and skin pigmentation

    PubMed Central

    Park, Jong il; Lee, Ha Yeon; Lee, Ji Eun; Myung, Cheol hwan; Hwang, Jae Sung

    2016-01-01

    Melanosomes are lysosome-related organelles with specialized capabilities of melanin synthesis and movement mediated by the Rab27a-Melanophilin-MyosinVa protein complex. In this study, we found that 2-methyl-naphtho[1,2,3-de]quinolin-8-one (MNQO) induced melanosome aggregation around the nucleus in melan-a melanocytes and in melan-a melanocytes/SP-1 keratinocyte co-cultures without inducing toxicity or changing the melanin content. Western blot and real-time PCR analyses showed that MNQO decreased expression of the Rab27a, Melanophilin and MyosinVa proteins and mRNAs, respectively, in melan-a melanocytes. In a reconstituted human epidermis model, treatment with 0.001% MNQO reduced skin pigmentation. Also, MNQO reduced skin pigmentation in brown guinea pigs induced by UVB irradiation. These results indicated that regulation of melanosome transport may serve as a good target for new skin depigmenting agents and MNQO itself could be a candidate. PMID:27381646

  7. Detection of Pigment Networks in Dermoscopy Images

    NASA Astrophysics Data System (ADS)

    Eltayef, Khalid; Li, Yongmin; Liu, Xiaohui

    2017-02-01

    One of the most important structures in dermoscopy images is the pigment network, which is also one of the most challenging and fundamental task for dermatologists in early detection of melanoma. This paper presents an automatic system to detect pigment network from dermoscopy images. The design of the proposed algorithm consists of four stages. First, a pre-processing algorithm is carried out in order to remove the noise and improve the quality of the image. Second, a bank of directional filters and morphological connected component analysis are applied to detect the pigment networks. Third, features are extracted from the detected image, which can be used in the subsequent stage. Fourth, the classification process is performed by applying feed-forward neural network, in order to classify the region as either normal or abnormal skin. The method was tested on a dataset of 200 dermoscopy images from Hospital Pedro Hispano (Matosinhos), and better results were produced compared to previous studies.

  8. Risk Factors in Patients with Venous Stasis-Related Skin Lesions without Major Abnormalities on Duplex Ultrasonography.

    PubMed

    Suehiro, Kotaro; Morikage, Noriyasu; Yamashita, Osamu; Harada, Takasuke; Samura, Makoto; Takeuchi, Yuriko; Mizoguchi, Takahiro; Hamano, Kimikazu

    2016-01-01

    Purpose: To clarify the risk factors for venous stasis-related skin lesions in the legs in patients without major abnormalities on duplex ultrasonography (DUS). Methods: Fifty patients (nine males and 41 females, age 27-93 years) with symptoms of C4 or greater according to the Clinical, Etiological, Anatomical, Pathological (CEAP) classification, but having no abnormalities on DUS were reviewed for known risk factors for chronic venous insufficiency (CVI) such as older age (>70 years), obesity (body mass index [BMI] >30 kg/m(2)), short walking distance (<200 m/day), reduced ankle range of motion (<20°), and occupation requiring prolonged standing (>8h per day). Results: The risk factor was different between male and female patients; although all patients had at least one of the above risk factors, the most commonly found risk factor in male patients was occupation requiring prolonged standing (63%), while advanced age (78%) and limited walking distance (83%) were risk factors in female patients. Conclusions: Although male and female patients had different risk factors, insufficient walking seemed to be closely related to the development of venous stasis-related skin lesions.

  9. Risk Factors in Patients with Venous Stasis-Related Skin Lesions without Major Abnormalities on Duplex Ultrasonography

    PubMed Central

    Morikage, Noriyasu; Yamashita, Osamu; Harada, Takasuke; Samura, Makoto; Takeuchi, Yuriko; Mizoguchi, Takahiro; Hamano, Kimikazu

    2016-01-01

    Purpose: To clarify the risk factors for venous stasis-related skin lesions in the legs in patients without major abnormalities on duplex ultrasonography (DUS). Methods: Fifty patients (nine males and 41 females, age 27–93 years) with symptoms of C4 or greater according to the Clinical, Etiological, Anatomical, Pathological (CEAP) classification, but having no abnormalities on DUS were reviewed for known risk factors for chronic venous insufficiency (CVI) such as older age (>70 years), obesity (body mass index [BMI] >30 kg/m2), short walking distance (<200 m/day), reduced ankle range of motion (<20°), and occupation requiring prolonged standing (>8h per day). Results: The risk factor was different between male and female patients; although all patients had at least one of the above risk factors, the most commonly found risk factor in male patients was occupation requiring prolonged standing (63%), while advanced age (78%) and limited walking distance (83%) were risk factors in female patients. Conclusions: Although male and female patients had different risk factors, insufficient walking seemed to be closely related to the development of venous stasis-related skin lesions. PMID:27738462

  10. Correspondence between Pigmented Lesions Identified by Melanoma Patients Trained to Perform Partner-Assisted Skin Self-Examination and Dermatological Examination

    PubMed Central

    Stapleton, Jerod L.; Turrisi, Rob; Mallett, Kimberly A.; Robinson, June K.

    2015-01-01

    Background Skin-self examination (SSE) training interventions can increase understanding of melanoma early detection criteria and promote SSE. However, there remains a need to evaluate whether intervention participants can apply such early detection skills to accurately identify concerning, or potentially malignant, pigmented lesions during full body SSE. Methods We assessed SSE accuracy using data from a randomized control trial of a SSE skills training intervention designed to promote partner-assisted SSE among melanoma patients. In the trial, patient-partner pairs were administered the training intervention and performed monthly SSE to identify, evaluate, and track concerning pigmented skin lesions. Patients received a total body skin examination by a dermatologist approximately 4-months post-intervention. SSE accuracy was assessed as the correspondence between the specific concerning pigmented lesions identified by 274 study pairs during SSE with those identified during dermatological examination. We also examined whether lesions that were biopsied during the study were identified prior to biopsy during SSE. Results Approximately 3 in 4 of the concerning lesions identified by pairs during SSE were also identified during the dermatological exam. There were 81 biopsies performed during the study and pairs had identified 73% of the corresponding lesions during SSE. Of the 5 melanoma detected, 3 were identified during SSE. Conclusion Melanoma patients and partner taught to do SSE using an evidence-based program developed a high degree of correspondence with the study dermatologist in identifying concerning lesions. Impact This study provides novel evidence that supports the accuracy of full-body SSE for the patient identification of concerning lesions. PMID:26063475

  11. Mechanisms of abnormal lamellar body secretion and the dysfunctional skin barrier in patients with atopic dermatitis.

    PubMed

    Elias, Peter M; Wakefield, Joan S

    2014-10-01

    I review how diverse inherited and acquired abnormalities in epidermal structural and enzymatic proteins converge to produce defective permeability barrier function and antimicrobial defense in patients with atopic dermatitis (AD). Although best known are mutations in filaggrin (FLG), mutations in other member of the fused S-100 family of proteins (ie, hornerin [hrn] and filaggrin 2 [flg-2]); the cornified envelope precursor (ie, SPRR3); mattrin, which is encoded by TMEM79 and regulates the assembly of lamellar bodies; SPINK5, which encodes the serine protease inhibitor lymphoepithelial Kazal-type trypsin inhibitor type 1; and the fatty acid transporter fatty acid transport protein 4 have all been linked to AD. Yet these abnormalities often only predispose to AD; additional acquired stressors that further compromise barrier function, such as psychological stress, low ambient humidity, or high-pH surfactants, often are required to trigger disease. T(H)2 cytokines can also compromise barrier function by downregulating expression of multiple epidermal structural proteins, lipid synthetic enzymes, and antimicrobial peptides. All of these inherited and acquired abnormalities converge on the lamellar body secretory system, producing abnormalities in lipid composition, secretion, and/or extracellular lamellar membrane organization, as well as antimicrobial defense. Finally, I briefly review therapeutic options that address this new pathogenic paradigm.

  12. Abnormal Collagen Metabolism in Cultured Skin Fibroblasts from Patients with Duchenne Muscular Dystrophy

    NASA Astrophysics Data System (ADS)

    Rodemann, H. Peter; Bayreuther, Klaus

    1984-08-01

    Total collagen synthesis is decreased by about 29% (P < 0.01) in skin fibroblasts established in vitro from male patients with Duchenne muscular dystrophy (DMD) as compared with that in normal male skin fibroblasts in vitro. The reduction in collagen synthesis is associated with an approximately 2-fold increase in collagen degradation in DMD fibroblasts. Correlated to these alterations in the metabolism of collagen, DMD fibroblasts express a significantly higher hydroxyproline/proline ratio (DMD: 1.36-1.45; P < 0.01) than do normal fibroblasts (controls: 0.86-0.89). The increased hydroxylation of proline residues of collagen (composed of type I and type III) could be the cause for the enhanced degradation of collagen in DMD fibroblasts.

  13. Assessment of a Diagnostic Predictive Probability Model Provided by a Multispectral Digital Skin Lesion Analysis Device for Melanoma and Other High-risk Pigmented Lesions and its Impact on Biopsy Decisions

    PubMed Central

    Yoo, Jane; Tucker, Natalie; White, Richard; Rigel, Darrell S.

    2014-01-01

    Objective: Risk prediction models for primary malignant melanoma thus far have relied on qualitative patient information. The authors propose a quantitative diagnostic predictive probability model using Multispectral Digital Skin Lesion Analysis for melanoma and other high-risk pigmented lesions and evaluate its effectiveness optimizing biopsy decisions by dermatologists. Design: Data from 1,632 pigmented lesions analyzed by a Multispectral Digital Skin Lesion Analysis device were used to perform a logistic regression analysis. This new quantitative melanoma or melanoma/atypical melanocytic hyperplasia/high-grade dysplastic nevus probability model was then evaluated to determine its impact on dermatologist decisions to biopsy pigmented lesions clinically suggestive of melanoma. Participants were given an electronic keypad and answered “yes” or “no” if they would biopsy each of 12 pigmented lesions when presented first with patient history, clinical images, and dermoscopic images and again when subsequently shown Multispectral Digital Skin Lesion Analysis data. Setting/participants: Study of 191 dermatologists at a medical conference. Measurements: Sensitivity, specificity, biopsy accuracy, overall biopsy rate, and percentage dermatologists biopsying all five melanomas. Results: Dermatologists were significantly more sensitive, specific, and accurate while decreasing overall biopsy rates with Multispectral Digital Skin Lesion Analysis probability information. Conclusion: Integration of Multispectral Digital Skin Lesion Analysis probability information in the biopsy evaluation and selection process of pigmented lesions has the potential to improve melanoma sensitivity of dermatologists without the concomitant costs associated with additional biopsies being performed. PMID:25584133

  14. 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.

  15. Cell surface abnormality in clones of skin fibroblasts from a carrier of Duchenne muscular dystrophy.

    PubMed Central

    Hillier, J; Jones, G E; Statham, H E; Witkowski, J A; Dubowitz, V

    1985-01-01

    We have previously reported that skin fibroblasts from patients with Duchenne muscular dystrophy (DMD) have a lower intercellular adhesiveness than control cells, and that cells from carriers of DMD have normal adhesiveness instead of the expected intermediate value. We have now cloned skin fibroblasts from a carrier of DMD (subject AS) who is also heterozygous for G6PD B/G6PD Mediterranean and determined the intercellular adhesiveness and G6PD phenotypes of the clones. G6PD activity was determined using the 2d-G6P/G6P ratio method. Normal cells had a percentage utilisation of 7.31% and uncloned cells from AS a value of 25.16%. Of 16 clones, 15 had normal values (mean 8.72%) while one clone was G6PD Med with a value of 57.5%. Mean intercellular adhesiveness of normal and uncloned cells from AS were 2.95 and 2.90 respectively. Of 11 clones tested, nine had normal values of adhesiveness (mean 3.1) and all these clones were G6PD B. The single G6PD Med clone had a value of 0.88, compared with 1.39 for DMD cells. We have no explanation at present for the single clone that was G6PD B but DMD-like on aggregation. PMID:3989823

  16. FGFR2 abnormalities underlie a spectrum of bone, skin, and cancer pathologies.

    PubMed

    Katoh, Masaru

    2009-08-01

    Fibroblast growth factor receptor (FGFR)2 is regulated on the basis of the balance of FGFs, heparan-sulfate proteoglycans, FGFR2 isoforms, endogenous inhibitors, and microRNAs. FGFR2 signals cross-talk with hedgehog, bone morphogenetic protein, and other regulatory networks. Some cases of congenital skeletal disorders with an FGFR2 mutation show skin phenotypes, including acne, cutis gyrata, and acanthosis nigricans. Gain-of-function mutations or variations of human FGFR2 occur in estrogen receptor-positive breast cancer, diffuse-type gastric cancer, and endometrial uterine cancer. Oral administration of AZD2171 or Ki23057 inhibits in vivo proliferation of cancer cells with aberrant FGFR2 activation in rodent therapeutic models. However, loss-of-function mutations of FGFR2 are reported in human melanoma. Conditional Fgfr2b knockout in the rodent epidermis leads to increased macrophage infiltration to the dermis and adipose tissue, epidermal thickening accompanied by basal-layer dysplasia and parakeratosis, and the promotion of chemically induced squamous-cell carcinoma. Dysregulation of FGFR2 results in a spectrum of bone and skin pathologies and several types of cancer.

  17. Skin ceramide alterations in first-episode schizophrenia indicate abnormal sphingolipid metabolism.

    PubMed

    Smesny, Stefan; Schmelzer, Christian E H; Hinder, Anke; Köhler, Alexandra; Schneider, Christiane; Rudzok, Maria; Schmidt, Ulrike; Milleit, Berko; Milleit, Christine; Nenadic, Igor; Sauer, Heinrich; Neubert, Reinhard H H; Fluhr, Joachim W

    2013-07-01

    There is considerable evidence for specific pathology of lipid metabolism in schizophrenia, affecting polyunsaturated fatty acids and in particular sphingolipids. These deficits are assumed to interfere with neuronal membrane functioning and the development and maintenance of myelin sheaths. Recent studies suggest that some of these lipid pathologies might also be detected in peripheral skin tests. In this study, we examined different skin lipids and their relation to schizophrenia. We assessed epidermal lipid profiles in 22 first-episode antipsychotic-naïve schizophrenia patients and 22 healthy controls matched for age and gender using a hexan/ethanol extraction technique and combined high-performance thin-layer chromatography/gas-chromatography. We found highly significant increase of ceramide AH and NH/AS classes in patients and decrease of EOS and NP ceramide classes. This is the first demonstration of specific peripheral sphingolipid alterations in schizophrenia. The results support recent models of systemic lipid pathology and in particular of specific sphingolipids, which are crucial in neuronal membrane integrity. Given recent findings showing amelioration of psychopathology using fatty acid supplementation, our findings also bear relevance for sphingolipids as potential biomarkers of the disease.

  18. White Matter Abnormalities in Skin Picking Disorder: A Diffusion Tensor Imaging Study

    PubMed Central

    Grant, Jon E; Odlaug, Brian L; Hampshire, Adam; Schreiber, Liana RN; Chamberlain, Samuel R

    2013-01-01

    Skin picking disorder (SPD) is characterized by the repetitive and compulsive picking of skin, resulting in tissue damage. Neurocognitive findings in SPD implicate difficulty with response inhibition (suppression of pre-potent motor responses). This function is dependent on the integrity of the right frontal gyrus and the anterior cingulate cortices, and white-matter tracts connecting such neural nodes. It was hypothesized that SPD would be associated with reduced fractional anisotropy in regions implicated in top-down response suppression, particularly white-matter tracts in proximity of the bilateral anterior cingulate and right frontal (especially orbitofrontal and inferior frontal) cortices. 13-subjects meeting proposed SPD criteria for DSM-5 free from other current psychiatric comorbidities, and 12 healthy comparison subjects underwent MRI with a 3-T system. Between-group comparisons of imaging data underwent voxelwise analysis with permutation modeling and cluster correction. Fractional anisotropy (measured using diffusion tensor imaging) was the primary outcome measure. Subjects with SPD exhibited significantly reduced fractional anisotropy in tracts distributed bilaterally, which included the anterior cingulate cortices. Fractional anisotropy did not correlate significantly with SPD disease severity, or depressive or anxiety scores. These findings implicate disorganization of white-matter tracts involved in motor generation and suppression in the pathophysiology of SPD, findings remarkably similar to those previously reported in trichotillomania. This study adds considerable support to the notion that—in addition to the phenomenological and comorbid overlap between SPD and trichotillomania—these disorders likely share overlapping neurobiology. PMID:23303052

  19. A systematic review of the influence of skin pigmentation on changes in the concentrations of vitamin D and 25-hydroxyvitamin D in plasma/serum following experimental UV irradiation.

    PubMed

    Xiang, Fan; Lucas, Robyn; de Gruijl, Frank; Norval, Mary

    2015-12-01

    Defining whether skin pigmentation influences vitamin D photosynthesis is important for delivering accurate public health messages. Current evidence is contradictory. We undertook a systematic review of the published literature to examine the association between skin pigmentation and change in blood concentrations of vitamin D and 25-hydroxyvitamin D following experimental UV irradiation. Twelve studies fulfilled the inclusion criteria: human study in vivo with non-diseased participants; controlled artificial UV radiation; vitamin D or 25-hydroxyvitamin D measured in serum or plasma; full text in English. In seven studies, vitamin D photosynthesis was reduced in dark-skinned compared with fairer-skinned individuals. In the remaining five studies, only one of which was published after 1990, there was no difference in vitamin D photosynthesis according to skin type. The disparities in these results may be due to small sample sizes and variations in study methodology, including the source, dose and frequency of UV irradiation, phototype classification, and analysis of vitamin D and 25-hydroxyvitamin D. Of these, the spectrum emitted by the UV lamps may be significant. No study considered potential modifying factors, such as relevant genetic polymorphisms. On balance, we conclude that pigmented skin has less effective photoproduction of vitamin D and 25-hydroxyvitamin D. The quantity of sun exposure needed for dark-skinned, compared with light-skinned, people to achieve vitamin D sufficiency remains uncertain.

  20. Genetics of psoriasis: evidence for epistatic interaction between skin barrier abnormalities and immune deviation.

    PubMed

    Bergboer, Judith G M; Zeeuwen, Patrick L J M; Schalkwijk, Joost

    2012-10-01

    Psoriasis was until recently regarded as a T-cell-driven disease with presumed (auto)immune mechanisms as its primary cause. This view was supported by clinical data and genetic studies that identified risk factors functioning in adaptive and innate immunity, such as HLA-C*06, ERAP1, the IL-23 pathway, and NF-k B signaling. Candidate gene approaches and genome-wide association studies, however, have identified copy number polymorphisms of the b-defensin cluster and deletion of late cornified envelope (LCE) 3B and 3C genes (LCE3C_LCE3B-del) as psoriasis risk factors.As these genes are expressed in epithelial cells and not by the immune system, these findings may cause a change of paradigm for psoriasis, not unlike the reported filaggrin association that has profoundly changed the views on atopic dermatitis. In addition to genetic polymorphisms of the immune system, genetic variations affecting the skin barrier are likely to contribute to psoriasis. Recent studies have shown epistatic interactions involving HLA-C*06, ERAP1, and LCE3C_LCE3B-del, which makes psoriasis a unique model to investigate genetic and biological interactions of associated genes in a complex disease. We present a model for disease initiation and perpetuation, which integrates the available genetic, immunobiological, and clinical data.

  1. Exposure to acute electromagnetic radiation of mobile phone exposure range alters transiently skin homeostasis of a model of pigmented reconstructed epidermis.

    PubMed

    Simon, D; Daubos, A; Pain, C; Fitoussi, R; Vié, K; Taieb, A; de Benetti, L; Cario-André, M

    2013-02-01

    Exposure to electromagnetic radiations (EMR) produced by mobile phone concerns half the world's population and raises the problem of their impact on human health. In this study, we looked at the effects of mobile phone exposure (GSM basic, 900 MHz, SAR 2 mW g(-1) , 6 h) on a model of pigmented skin. We have analysed the expression and localization of various markers of keratinocyte and melanocyte differentiation 2, 6, 18 and 24 h after EMR exposure of reconstructed epidermis containing either only keratinocytes or a combination of keratinocytes and melanocytes grown on dead de-epidermized dermis, using histology, immunohistochemistry and Western blot. No changes were found in epidermal architecture, localization of epidermal markers, presence of apoptotic cells and the induction of p53 in both types of epidermis (with or without melanocytes) after exposure to EMR. In pigmented reconstructs, no change in the location and dendricity of melanocytes and in melanin transfer to neighbouring keratinocytes was detected after EMR exposure. Loricrin, cytokeratin 14 were significantly decreased at 6 h. The level of all markers increased at 24 h as compared to 6 h post-EMR exposure, associated with a significant decrease of the 20S proteasome activity. Our data indicate that exposure to 900 MHz frequency induces a transient alteration of epidermal homoeostasis, which may alter the protective capacity of the skin against external factors. Presence or absence of melanocytes did not modify the behaviour of reconstructs after EMR exposure.

  2. The stimulatory effect of LED light spectra on genes related to photoreceptors and skin pigmentation in goldfish (Carassius auratus).

    PubMed

    Shin, Hyun Suk; Choi, Cheol Young

    2014-08-01

    This study aimed to assess differences in genes related to skin color of goldfish (Carassius auratus) exposed to light-emitting diodes (LEDs): red, green, and purple. We investigated differences in the expression of mammalian-like melanopsin (Opn4m), rhodopsin (RH), melanin-concentrating hormone (MCH), melanin-concentrating hormone receptor (MCH-R), and proopiomelanocortin (POMC) in goldfish exposed to different LED light spectra. Opn4m, RH, MCH, and MCH-R mRNA levels were significantly higher in the green and purple LED groups than in the white fluorescent bulb (control) and red LED groups. Furthermore, skin cells were isolated to measure the MCH-R mRNA expression levels. The results show that the mRNA expression levels were significantly higher in the green and purple LED groups than in the control and red LED groups. In addition, body weights in the green and purple LED groups were significantly higher than those in the control and red LED groups. However, POMC mRNA expression levels in the green and purple LED groups were significantly lower than those in the control and red LED groups. These results suggest that specific wavelengths regulate fish skin color through neuropeptide hormones and photoreceptors, and POMC, which is related to stress hormones and melatonin, is associated with stress levels as well as skin color.

  3. Ion transport in pigmentation

    PubMed Central

    Bellono, Nicholas W.; Oancea, Elena V.

    2014-01-01

    Skin melanocytes and ocular pigment cells contain specialized organelles called melanosomes, which are responsible for the synthesis of melanin, the major pigment in mammals. Defects in the complex mechanisms involved in melanin synthesis and regulation result in vision and pigmentation deficits, impaired development of the visual system,, and increased susceptibility to skin and eye cancers. Ion transport across cellular membranes is critical for many biological processes, including pigmentation, but the molecular mechanisms by which it regulates melanin synthesis, storage, and transfer are not understood. In this review we first discuss ion channels and transporters that function at the plasma membrane of melanocytes; in the second part we consider ion transport across the membrane of intracellular organelles, with emphasis on melanosomes. We discuss recently characterized lysosomal and endosomal ion channels and transporters associated with pigmentation phenotypes. We then review the evidence for melanosomal channels and transporters critical for pigmentation, discussing potential molecular mechanisms mediating their function. The studies investigating ion transport in pigmentation physiology open new avenues for future research and could reveal novel molecular mechanisms underlying melanogenesis. PMID:25034214

  4. Ion transport in pigmentation.

    PubMed

    Bellono, Nicholas W; Oancea, Elena V

    2014-12-01

    Skin melanocytes and ocular pigment cells contain specialized organelles called melanosomes, which are responsible for the synthesis of melanin, the major pigment in mammals. Defects in the complex mechanisms involved in melanin synthesis and regulation result in vision and pigmentation deficits, impaired development of the visual system, and increased susceptibility to skin and eye cancers. Ion transport across cellular membranes is critical for many biological processes, including pigmentation, but the molecular mechanisms by which it regulates melanin synthesis, storage, and transfer are not understood. In this review we first discuss ion channels and transporters that function at the plasma membrane of melanocytes; in the second part we consider ion transport across the membrane of intracellular organelles, with emphasis on melanosomes. We discuss recently characterized lysosomal and endosomal ion channels and transporters associated with pigmentation phenotypes. We then review the evidence for melanosomal channels and transporters critical for pigmentation, discussing potential molecular mechanisms mediating their function. The studies investigating ion transport in pigmentation physiology open new avenues for future research and could reveal novel molecular mechanisms underlying melanogenesis.

  5. Validation of brief questionnaire measures of sun exposure and skin pigmentation against detailed and objective measures including vitamin D status.

    PubMed

    Cargill, Jessica; Lucas, Robyn M; Gies, Peter; King, Kerryn; Swaminathan, Ashwin; Allen, Martin W; Banks, Emily

    2013-01-01

    Self-reported sun exposure is commonly used in research, but how well this represents actual sun exposure is poorly understood. From February to July 2011, a volunteer sample (n = 47) of older adults (≥45 years) in Canberra, Australia, answered brief questions on time outdoors (weekdays and weekends) and natural skin color. They subsequently maintained a sun diary and wore an ultraviolet radiation (UVR) digital dosimeter for 7 days. Melanin density was estimated using reflectance spectrophotometry; lifetime sun damage was assessed using silicone casts of the back of the hand; and serum 25-hydroxyvitamin D (25(OH)D) concentration was assayed. Questionnaire-reported time outdoors correlated significantly with diary-recorded time outdoors (Spearman correlation r(s) = 0.66; 95% CI 0.46, 0.80; P < 0.001) and UVR dosimeter dose (r(s ) = 0.46; 95% CI 0.18, 0.68; P = 0.003), but not 25(OH)D concentration (r(s) = 0.24; 95% CI -0.05, 0.50; P = 0.10). Questionnaire-reported untanned skin color correlated significantly with measured melanin density at the inner upper arm (r(s) = 0.49; 95% CI 0.24, 0.68; P < 0.001). In a multiple linear regression model, statistically significant predictors of 25(OH)D concentration were self-reported frequency of physical activity, skin color and recent osteoporosis treatment (R(2) = 0.54). In this study, brief questionnaire items provided valid rankings of sun exposure and skin color, and enabled the development of a predictive model for 25(OH)D concentration.

  6. Biology of pigmentation

    SciTech Connect

    Parker, F.

    1981-01-01

    The many factors involved in the normal pigmentation of human skin are highly complex involving anatomic, biochemical, and genetic aspects of melanocytes in the skin and the influence of UV light and various hormones on the melanocytes. It is probably more than just coincidence that the melanocytes, which are of neurogenic origin, are so responsive to several trophic hormones produced in the brain. Understanding of the various factors involved in the normal pigmentary process is crucial to explaining the many alterations and anomalies in human pigmentation.

  7. Imaging mass spectrometry visualizes ceramides and the pathogenesis of dorfman-chanarin syndrome due to ceramide metabolic abnormality in the skin.

    PubMed

    Goto-Inoue, Naoko; Hayasaka, Takahiro; Zaima, Nobuhiro; Nakajima, Kimiko; Holleran, Walter M; Sano, Shigetoshi; Uchida, Yoshikazu; Setou, Mitsutoshi

    2012-01-01

    Imaging mass spectrometry (IMS) is a useful cutting edge technology used to investigate the distribution of biomolecules such as drugs and metabolites, as well as to identify molecular species in tissues and cells without labeling. To protect against excess water loss that is essential for survival in a terrestrial environment, mammalian skin possesses a competent permeability barrier in the stratum corneum (SC), the outermost layer of the epidermis. The key lipids constituting this barrier in the SC are the ceramides (Cers) comprising of a heterogeneous molecular species. Alterations in Cer composition have been reported in several skin diseases that display abnormalities in the epidermal permeability barrier function. Not only the amounts of different Cers, but also their localizations are critical for the barrier function. We have employed our new imaging system, capable of high-lateral-resolution IMS with an atmospheric-pressure ionization source, to directly visualize the distribution of Cers. Moreover, we show an ichthyotic disease pathogenesis due to abnormal Cer metabolism in Dorfman-Chanarin syndrome, a neutral lipid storage disorder with ichthyosis in human skin, demonstrating that IMS is a novel diagnostic approach for assessing lipid abnormalities in clinical setting, as well as for investigating physiological roles of lipids in cells/tissues.

  8. "Syndrome myxoma": a subset of patients with cardiac myxoma associated with pigmented skin lesions and peripheral and endocrine neoplasms.

    PubMed Central

    Vidaillet, H J; Seward, J B; Fyke, F E; Su, W P; Tajik, A J

    1987-01-01

    From January 1954 to December 1985 cardiac myxoma was diagnosed in 75 patients at the Mayo Clinic. The clinical presentation was typical in 70 cases and was referred to as "sporadic myxoma". Forty four other cases of cardiac myxomas (five from the Mayo Clinic) presented with a combination of distinctive clinical features and these cases are described as "syndrome myxoma". The patients with syndrome myxoma were younger (mean age, 25 vs 56 years) and had unusual skin freckling (68%), associated benign non-cardiac myxomatous tumours (57%), endocrine neoplasms (30%), and a high frequency of familial cardiac myxoma (25%) and familial endocrine tumours (14%). The two types of cardiac tumour were different (syndrome vs sporadic): atrial location, 87% vs 100%; ventricular location, 13% vs 0%; single tumour, 50% vs 99%; multiple tumours, 50% vs 1%; and recurrent tumour, 18% vs 0%. It is concluded that patients with syndrome myxoma represent a distinctive subgroup in which there are important clinical, surgical, and genetic implications. More importantly, syndrome myxoma appears to be only one expression of a much larger disease entity. Images Fig 3 Fig 1 Fig 2 Fig 4 PMID:3566983

  9. Natural considerations for skin of color.

    PubMed

    Baumann, Leslie; Rodriguez, David; Taylor, Susan C; Wu, Jessica

    2006-12-01

    Changing US demographics indicate that dermatologists will treat an increasing number of individuals of color. Early research on cutaneous anatomy and physiology was performed mostly in white populations. However, new research is elucidating similarities and differences in skin of color and white skin with regard to skin barrier, pigmentation, and sensitivity. Two of the most important issues are skin lightening and brightening. Products for use on skin of color typically should be gentle because of the proclivity of more deeply pigmented skin to develop pigmentary abnormalities in response to skin irritation or trauma. Increasing patient interest in natural remedies has been matched by research on the use of natural ingredients in dermatology. The relative gentleness of many of these products, coupled with excellent efficacy, makes natural ingredients such as soy and licorice excellent choices in the treatment of disorders such as postinflammatory hyperpigmentation (PIH) and melasma. For daily skin care, ingredients such as oatmeal and feverfew are good choices for gentle cleansing and moisturizing of dry, sensitive, or ashy skin. Sun protection is an increasing concern due to rising rates of melanoma. Several botanical products are useful in augmenting photoprotection with conventional sunscreens.

  10. Reevaluation of the non-lesional dry skin in atopic dermatitis by acute barrier disruption: an abnormal permeability barrier homeostasis with defective processing to generate ceramide.

    PubMed

    Sugiura, Ayumi; Nomura, Tsuyoshi; Mizuno, Atsuko; Imokawa, Genji

    2014-07-01

    Atopic dermatitis is characterized by disruption of the cutaneous barrier due to reduced ceramide levels even in non-lesional dry skin. Following further acute barrier disruption by repeated tape strippings, we re-characterized the non-lesional dry skin of subjects with atopic dermatitis, which shows significantly reduced levels of barrier function and ceramide but not of beta-glucocerebrosidase activity. For the first time, we report an abnormal trans-epidermal water loss homeostasis in which delayed recovery kinetics of trans-epidermal water loss occurred on the first day during the 4 days after acute barrier disruption compared with healthy control skin. Interestingly, whereas the higher ceramide level in the stratum corneum of healthy control skin was further significantly up-regulated at 4 days post-tape stripping, the lower ceramide level in the stratum corneum of subjects with atopic dermatitis was not significantly changed. In a parallel study, whereas beta-glucocerebrosidase activity at 4 days post-tape stripping was significantly up-regulated in healthy control skin compared with before tape stripping, the level of that activity remained substantially unchanged in atopic dermatitis. These findings indicate that subjects with atopic dermatitis have a defect in sphingolipid-metabolic processing that generates ceramide in the interface between the stratum corneum and the epidermis. The results also support the notion that the continued disruption of barrier function in atopic dermatitis non-lesional skin is associated with the impaired homeostasis of a ceramide-generating process, which underscores an atopy-specific inflammation-triggered ceramide deficiency that is distinct from other types of dermatitis.

  11. Components of skin

    MedlinePlus Videos and Cool Tools

    ... skin layers from the outside environment and contains cells that make keratin, a substance that waterproofs and strengthens the skin. The epidermis also has cells that contain melanin, the dark pigment that gives ...

  12. Analysis of gene expression dynamics revealed delayed and abnormal epidermal repair process in aged compared to young skin.

    PubMed

    Sextius, Peggy; Marionnet, Claire; Tacheau, Charlotte; Bon, François-Xavier; Bastien, Philippe; Mauviel, Alain; Bernard, Bruno A; Bernerd, Françoise; Dubertret, Louis

    2015-05-01

    With aging, epidermal homeostasis and barrier function are disrupted. In a previous study, we analyzed the transcriptomic response of young skin epidermis after stratum corneum removal, and obtained a global kinetic view of the molecular processes involved in barrier function recovery. In the present study, the same analysis was performed in aged skin in order to better understand the defects which occur with aging. Thirty healthy male volunteers (67 ± 4 years old) were involved. Tape-strippings were carried out on the inner face of one forearm, the other unstripped forearm serving as control. At 2, 6, 18, 30 and 72 h after stripping, TEWL measurements were taken, and epidermis samples were collected. Total RNA was extracted and analyzed using DermArray(®) cDNA microarrays. The results highlighted that barrier function recovery and overall kinetics of gene expression were delayed following stripping in aged skin. Indeed, the TEWL measurements showed that barrier recovery in the young group appeared to be dramatically significant during the overall kinetics, while there were no significant evolution in the aged group until 30 h. Moreover, gene expression analysis revealed that the number of modulated genes following tape stripping increased as a function of time and reached a peak at 6 h after tape stripping in young skin, while it was at 30 h in aged skin, showing that cellular activity linked to the repair process may be engaged earlier in young epidermis than in aged epidermis. A total of 370 genes were modulated in the young group. In the aged group, 382 genes were modulated, whose 184 were also modulated in the young group. Only eight genes that were modulated in both groups were significantly differently modulated. The characterization of these genes into 15 functional families helped to draw a scenario for the aging process affecting epidermal repair capacity.

  13. Compound heterozygous desmoplakin mutations result in a phenotype with a combination of myocardial, skin, hair, and enamel abnormalities.

    PubMed

    Mahoney, My G; Sadowski, Sara; Brennan, Donna; Pikander, Pekka; Saukko, Pekka; Wahl, James; Aho, Heikki; Heikinheimo, Kristiina; Bruckner-Tuderman, Leena; Fertala, Andrzej; Peltonen, Juha; Uitto, Jouni; Peltonen, Sirkku

    2010-04-01

    Desmoplakin (DP) anchors the intermediate filament cytoskeleton to the desmosomal cadherins and thereby confers structural stability to tissues. In this study, we present a patient with extensive mucocutaneous blisters, epidermolytic palmoplantar keratoderma, nail dystrophy, enamel dysplasia, and sparse woolly hair. The patient died at the age of 14 years from undiagnosed cardiomyopathy. The skin showed hyperplasia and acantholysis in the mid- and lower epidermal layers, whereas the heart showed extensive fibrosis and fibrofatty replacement in both ventricles. Immunofluorescence microscopy showed a reduction in the C-terminal domain of DP in the skin and oral mucosa. Sequencing of the DP gene showed undescribed mutations in the maternal and paternal alleles. Both mutations affected exon 24 encoding the C-terminal domain. The paternal mutation, c.6310delA, leads to a premature stop codon. The maternal mutation, c.7964 C to A, results in a substitution of an aspartic acid for a conserved alanine residue at amino acid 2655 (A2655D). Structural modeling indicated that this mutation changes the electrostatic potential of the mutated region of DP, possibly altering functions that depend on intermolecular interactions. To conclude, we describe a combination of DP mutation phenotypes affecting the skin, heart, hair, and teeth. This patient case emphasizes the importance of heart examination of patients with desmosomal genodermatoses.

  14. Penicillamine-induced elastosis perforans serpiginosa with abnormal "lumpy-bumpy" elastic fibers in lesional and non-lesional skin.

    PubMed

    Khatu, Swapna S; Dhurat, Rachita S; Nayak, Chitra S; Pereira, Rickson R; Kagne, Rucha B

    2011-01-01

    Four types of elastosis perforans serpiginosa (EPS) have been described in literature: 1) idiopathic EPS, 2) reactive perforating elastosis associated with connective tissue disorders, 3) in some instances of pseudoxanthoma elasticum (PXE), disease-specific calcified elastic tissue is extruded, producing a clinical picture indistinguishable from other types, may also be seen in patients undergoing hemodialysis and 4) EPS induced by long-term treatment with D-penicillamine is observed in patients suffering from Wilson's disease. Long term D-penicillamine therapy causes an alteration in the dermal elastic tissue. D-penicillamine induced EPS has a distinctive histopathologic feature - serrated appearance of elastic fibers due to perpendicular budding from their surface giving a "lumpy-bumpy" look. D-penicillamine induced elastic fiber alteration may not always manifest clinically as EPS. We report a case of D-penicillamine induced widespread alteration in skin elastic tissue with distinct histopathologic features.

  15. Birthmarks - pigmented

    MedlinePlus

    ... colored skin cells. Mongolian spots (also called Mongolian blue spots) are usually bluish or bruised-looking. They ... Cafe-au-lait spots; Congenital nevus Images Mongolian blue spots Skin layers References Habif TP. Premalignant and ...

  16. Cutaneous metastatic pigmented breast carcinoma.

    PubMed

    Gaitan-Gaona, Francisco; Said, Mirra C; Valdes-Rodriguez, Rodrigo

    2016-03-16

    A 66-year-old woman presented with a 3 cm black, ulcerated nodule located on the skin of the upper abdomen, just below the breast. The lesion was painful to the touch, but the patient reported no other associated symptoms and was otherwise healthy. A 4-mm punch biopsy of the affected skin was obtained and the histological diagnosis was cutaneous metastatic pigmented breast carcinoma.

  17. Pigments in avocado tissue and oil.

    PubMed

    Ashton, Ofelia B O; Wong, Marie; McGhie, Tony K; Vather, Rosheila; Wang, Yan; Requejo-Jackman, Cecilia; Ramankutty, Padmaja; Woolf, Allan B

    2006-12-27

    Pigments are important contributors to the appearance and healthful properties of both avocado fruits and the oils extracted from these fruits. This study determined carotenoid and chlorophyll pigment concentrations in the skin and three sections of the flesh (outer dark green, middle pale green, and inner yellow flesh-nearest the seed) and anthocyanin concentrations in the skin of Hass avocado during ripening at 20 degrees C. Pigments were extracted from frozen tissue with acetone and measured using high-performance liquid chromatography. Pigments were also measured in the oil extracted from freeze-dried tissue sections by an accelerated solvent extraction system using hexane. Carotenoids and chlorophylls identified in the skin, flesh, and oil were lutein, alpha-carotene, beta-carotene, neoxanthin, violaxanthin, zeaxanthin, antheraxanthin, chlorophylls a and b, and pheophytins a and b with the highest concentrations of all pigments in the skin. Chlorophyllides a and b were identified in the skin and flesh tissues only. As the fruit ripened and softened, the skin changed from green to purple/black, corresponding to changes in skin hue angle, and a concomitant increase in cyanidin 3-O-glucoside and the loss of chlorophyllide a. In flesh tissue, chroma and lightness values decreased with ripening, with no changes in hue angle. The levels of carotenoids and chlorophylls did not change significantly during ripening. As fruit ripened, the total chlorophyll level in the oil from the flesh sections remained constant but declined in the oil extracted from the skin.

  18. Clofazimine-induced Hair Pigmentation.

    PubMed

    Philip, Mariam; Samson, Joan Felicita; Simi, Puthenveedu Salahudeen

    2012-07-01

    A 45-year-old man was treated with WHO multibacillary multidrug therapy for borderline leprosy and high dose daily Clofazimine for lepra reaction. Along with the expected side effect of skin pigmentation, the patient also noticed darkening of previously grey hair. This colour persisted eight months after completing multibacillary multidrug therapy.

  19. Gain of 11q/cyclin D1 overexpression is an essential early step in skin cancer development and causes abnormal tissue organization and differentiation.

    PubMed

    Burnworth, B; Popp, S; Stark, H-J; Steinkraus, V; Bröcker, E B; Hartschuh, W; Birek, C; Boukamp, P

    2006-07-27

    Non-melanoma skin cancers, in particular keratoacanthomas (KAs) and squamous cell carcinomas (SCCs), have become highly frequent tumor types especially in immune-suppressed transplant patients. Nevertheless, little is known about essential genetic changes. As a paradigm of 'early' changes, that is, changes still compatible with tumor regression, we studied KAs by comparative genomic hybridization and show that gain of chromosome 11q is not only one of the most frequent aberration (8/18), but in four tumors also the only aberration. Furthermore, 11q gain correlated with amplification of the cyclin D1 locus (10/14), as determined by fluorescence in situ hybridization, and overexpression of cyclin D1 protein (25/31), as detected by immunohistochemistry. For unraveling the functional consequence, we overexpressed cyclin D1 in HaCaT skin keratinocytes. These cells only gained little growth advantage in conventional and in organotypic co-cultures. However, although the control vector-transfected cells formed a well-stratified and orderly differentiated epidermis-like epithelium, they showed deregulation of tissue architecture with an altered localization of proliferation and impaired differentiation. The most severe phenotype was seen in a clone that additionally upregulated cdk4 and p21. These cells lacked terminal differentiation, exhibited a more autonomous growth in vitro and in vivo and even formed tumors in two injection sites with a growth pattern resembling that of human KAs. Thus, our results identify 11q13 gain/cyclin D1 overexpression as an important step in KA formation and point to a function that exceeds its known role in proliferation by disrupting tissue organization and thereby allowing abnormal growth.

  20. Genetic abnormality of the visual pathways in a "white" tiger.

    PubMed

    Guillery, R W; Kaas, J H

    1973-06-22

    "White"tigers show an inherited reduction of pigment, produced by an autosomal recessive gene. The brain of one of these tigers shows an abnormality of the visual pathways similar to abnormalities that are associated with albinism in many other mammals. There is a close relationship between the reduced pigment formation, the pathway abnormality, and strabismus.

  1. NCKX5, a natural regulator of human skin colour variation, regulates the expression of key pigment genes MC1R and alpha-MSH and alters cholesterol homeostasis in normal human melanocytes.

    PubMed

    Wilson, Stephen; Ginger, Rebecca S; Dadd, Tony; Gunn, David; Lim, Fei-Ling; Sawicka, Magdalena; Sandel, Melanie; Schnetkamp, Paul P M; Green, Martin R

    2013-01-01

    Natural human skin colour is determined both by environmental exposure to ultraviolet light and through inherited genetic variation in a very limited number of genes. Variation of a non-synonymous single-nucleotide polymorphism (nsSNP; rs1426654) in the gene (SLC24A5) encoding the NCKX5 protein is associated with differences in constitutive skin colour in South Asians. The nsSNP encodes the substitution of alanine for threonine at residue 111 (A111T) near a transmembrane region required for exchanger activity, a region which is highly conserved across different species and between NCKX family members. We have shown that NCKX5 is located at the trans-Golgi network of melanocytes and functions as a potassium-dependent sodium-calcium exchanger. When heterologously expressed, the 111T variant of NCKX5 shows significantly lower exchanger activity than the A111 variant. We have postulated that lower exchanger activity causes the reduced melanogenesis and lighter skin in Thr111-positive individuals. We used gene expression microarrays with qPCR replication and validation to assess the impact of siRNA-mediated knockdown of SLC24A5 on the transcriptome of cultured normal human melanocytes (NHM). Very few genes associated with melanogenesis were altered at the transcript level except for MC1R, suggesting that SLC24A5 interacts with at least one well-characterized melanogenic signalling pathway. More surprisingly, the expression of a number of cholesterol homeostatic genes was altered after SLC24A5 knockdown, and the total cholesterol content of NHM was increased. Cholesterol has previously been identified as a potential melanogenic regulator, and our data imply that NCKX5 exchanger function influences natural variation in skin pigmentation via a novel, unknown mechanism affecting cellular sterol levels.

  2. Pigmented poroma with unusual location and dermatoscopic features

    PubMed Central

    Kassuga, Luiza E. B. P.; Jeunon, Thiago; Sousa, Maria Auxiliadora Jeunon; Campos-do-Carmo, Gabriella

    2012-01-01

    Poroma is a benign adnexal neoplasm with atn “poroid”/ductal differentiation that mimics benign and malignant skin tumors. Histopathology shows circumscribed proliferation of poroid cells intermingled with a variable number of cuticular cells. We report a case of pigmented poroma located on the face that simulated clinically and dermatoscopically a pigmented basal cell carcinoma. The features of pigmented and non-pigmented poromas were revisited in order to assist in the diagnosis. PMID:23785609

  3. Dermoscopic Features of Pigmented Bowen's Disease in a Japanese Female Mimicking Malignant Melanoma

    PubMed Central

    Inoue, Takayuki; Kobayashi, Ken; Sawada, Mizuki; Ishizaki, Sumiko; Ito, Haruo; Fujibayashi, Mariko; Tanaka, Masaru

    2010-01-01

    Various structures have been reported for dermoscopic features of pigmented Bowen's disease (BD), which could be a mimic of various pigmented skin lesions. A 79-year-old Japanese woman presented with a 3-year history of brown-black macule on her right upper arm without symptom. Dermoscopic examination demonstrated irregular flossy streaks, irregular brown dots/globules, blue-whitish regression structures, and overlaying whitish scaly areas. We suspected pigmented skin lesions including seborrheic keratosis, pigmented eccrine poroma, and malignant melanoma and excised completely with a 5 mm margin. Histopathological features were consistent with a diagnosis of pigmented BD. Although similar dermoscopic features might be revealed in pigmented skin lesions and it may occasionally be difficult to distinguish between pigmented BD and other pigmented skin lesions, dermoscopy would be useful in speculating pathologic features of pigmented BD. PMID:20811602

  4. Morphological abnormalities among lampreys

    USGS Publications Warehouse

    Manion, Patrick J.

    1967-01-01

    The experimental control of the sea lamprey (Petromyzon marinus) in the Great Lakes has required the collection of thousands of lampreys. Representatives of each life stage of the four species of the Lake Superior basin were examined for structural abnormalities. The most common aberration was the presence of additional tails. The accessory tails were always postanal and smaller than the normal tail. The point of origin varied; the extra tails occurred on dorsal, ventral, or lateral surfaces. Some of the extra tails were misshaped and curled, but others were normal in shape and pigment pattern. Other abnormalities in larval sea lampreys were malformed or twisted tails and bodies. The cause of the structural abnormalities is unknown. The presence of extra caudal fins could be genetically controlled, or be due to partial amputation or injury followed by abnormal regeneration. Few if any lampreys with structural abnormalities live to sexual maturity.

  5. Aging changes in skin

    MedlinePlus

    ... sun exposure with areas that are protected from sunlight. Natural pigments seem to provide some protection against ... Exposures to industrial and household chemicals Indoor heating Sunlight can cause: Loss of elasticity (elastosis) Noncancerous skin ...

  6. Mitochondrial dysfunction: a neglected component of skin diseases.

    PubMed

    Feichtinger, René G; Sperl, Wolfgang; Bauer, Johann W; Kofler, Barbara

    2014-09-01

    Aberrant mitochondrial structure and function influence tissue homeostasis and thereby contribute to multiple human disorders and ageing. Ten per cent of patients with primary mitochondrial disorders present skin manifestations that can be categorized into hair abnormalities, rashes, pigmentation abnormalities and acrocyanosis. Less attention has been paid to the fact that several disorders of the skin are linked to alterations of mitochondrial energy metabolism. This review article summarizes the contribution of mitochondrial pathology to both common and rare skin diseases. We explore the intriguing observation that a wide array of skin disorders presents with primary or secondary mitochondrial pathology and that a variety of molecular defects can cause dysfunctional mitochondria. Among them are mutations in mitochondrial- and nuclear DNA-encoded subunits and assembly factors of oxidative phosphorylation (OXPHOS) complexes; mutations in intermediate filament proteins involved in linking, moving and shaping of mitochondria; and disorders of mitochondrial DNA metabolism, fatty acid metabolism and heme synthesis. Thus, we assume that mitochondrial involvement is the rule rather than the exception in skin diseases. We conclude the article by discussing how improving mitochondrial function can be beneficial for aged skin and can be used as an adjunct therapy for certain skin disorders. Consideration of mitochondrial energy metabolism in the skin creates a new perspective for both dermatologists and experts in metabolic disease.

  7. Congenital Abnormalities

    MedlinePlus

    ... Listen Español Text Size Email Print Share Congenital Abnormalities Page Content Article Body About 3% to 4% ... of congenital abnormalities earlier. 5 Categories of Congenital Abnormalities Chromosome Abnormalities Chromosomes are structures that carry genetic ...

  8. Dermatoscopic findings of pigmented purpuric dermatosis*

    PubMed Central

    Ozkaya, Dilek Biyik; Emiroglu, Nazan; Su, Ozlem; Cengiz, Fatma Pelin; Bahali, Anil Gulsel; Yildiz, Pelin; Demirkesen, Cuyan; Onsun, Nahide

    2016-01-01

    Background Pigmented purpuric dermatosis is a chronic skin disorder of unknown aetiology characterised by symmetrical petechial and pigmented macules, often confined to the lower limbs. The aetiology of pigmented purpuric dermatosis is unknown. Dermatoscopy is a non-invasive diagnostic technique that allows the visualisation of morphological features invisible to the naked eye; it combines a method that renders the corneal layer of the skin translucent with an optical system that magnifies the image projected onto the retina. Objectives The aim of this study is to investigate the dermatoscopic findings of pigmented purpuric dermatosis. Methods This study enrolled patients diagnosed histopathologically with pigmented purpuric dermatosis who had dermatoscopic records. We reviewed the dermatoscopic images of PPD patients who attended the outpatient clinic in the Istanbul Dermatovenereology Department at the Bezmialem Vakıf University Medical Faculty. Results Dermatoscopy showed: coppery-red pigmentation (97%, n = 31) in the background, a brown network (34%, n = 11), linear vessels (22%, n = 7), round to oval red dots, globules, and patches (69%, n = 22; 75%, n = 24; 34%, n = 11; respectively), brown globules (26%, n = 8) and dots (53%, n = 17), linear brown lines (22%, n = 7), and follicular openings (13%, n = 4). Conclusion To our knowledge, this is the first study to report the dermatoscopy of pigmented purpuric dermatosis. In our opinion, dermatoscopy can be useful in the diagnosis of pigmented purpuric dermatosis. PMID:27828629

  9. A novel association of an uncommon pigmentation pattern: coexistence of cutis tricolor with intracranial teratoma and holoprosencephaly.

    PubMed

    Tekin, Burak; Yucelten, Ayse Deniz; Bayri, Yasar

    2014-10-15

    Cutis tricolor was first described in a 17-year-old male patient by Happle et al. as a rare coexistence of circumscribed hyperpigmentation and hypopigmentation close to each other on a background of normally pigmented skin. Cutis tricolor has been reported as an isolated cutaneous finding or in various associations. To the best of our knowledge, cutis tricolor in association with teratoma and holoprosencephaly has not been reported in the literature. Herein, we report a male patient who presented with a teratoma and a combination of whorl-like hypopigmentation together with hyperpigmented patches adjacent to each other on intermediately pigmented skin. This case report supports the view that cutis tricolor may be a marker of an underlying neurological abnormality.

  10. [Radiolucent pigment gallstones (author's transl)].

    PubMed

    Wosiewitz, U; Wolpers, C; Quint, P

    1978-12-01

    Pigment gallstones may be subdivided into three different types: radiolucent and radioopaque stones in the gallbladder and radiolucent stones in the common bile duct. 35 of our patients had radiolucent pigment stones in the gallbladder; 21 of these were followed for years by repeated X-ray examination. There is only little enlargement of these stones as time passes by, however the number of these stones increases continuously. Chemical analysis could be done on such stones in 24 cases. The stones were composed of granular calcium bilirubinate and of asphalt-like products derived from abnormal bilirubin degradation. 5 patients had pigment stones in the common bile duct. These stones contained little cholesterol and exhibited a spongy microstructure characterized by small tubules with a diameter of 1 micrometer. They contained more lipids and bilirubin than the stones collected from the gallbladder and on extraction with organic solvents no asphalt-like residues could be obtained.

  11. Microprobe analysis of chlorpromazine pigmentation

    SciTech Connect

    Benning, T.L.; McCormack, K.M.; Ingram, P.; Kaplan, D.L.; Shelburne, J.D.

    1988-10-01

    We describe the histochemical, ultrastructural, and microanalytical features of a skin biopsy specimen obtained from a patient with chlorpromazine pigmentation. Golden-brown pigment granules were present in the dermis, predominantly in a perivascular arrangement. The granules stained positively with the Fontana-Masson stain for silver-reducing substances and negatively with Perl's stain for iron. Electron microscopy revealed dense inclusion bodies in dermal histiocytes, pericytes, endothelial cells, and Schwann cells, as well as lying free in the extracellular matrix. These ''chlorpromazine bodies'' were quite dense even in unosmicated, unstained ultrathin sections, indicating that the pigmentation is related, at least in part, to the inclusions. Microprobe analysis of the chlorpromazine bodies revealed a striking peak for sulfur, which strongly suggests the presence of the drug or its metabolite within these inclusions.

  12. Melanogenesis inhibition by an oolong tea extract in b16 mouse melanoma cells and UV-induced skin pigmentation in brownish guinea pigs.

    PubMed

    Aoki, Yumi; Tanigawa, Tomoko; Abe, Hiroko; Fujiwara, Yoko

    2007-08-01

    To investigate the new physiological functions of oolong tea, the effects on melanogenesis were studied. An oolong tea extract inhibited melanogenesis without affecting cell growth in B16 mouse melanoma cells. However, the oolong tea extract hardly showed any inhibitory effect on mushroom tyrosinase in a cell-free system. The effects of an oolong tea extract on the intracellular tyrosinase level in B16 cells were therefore studied. All the levels of activity, protein and mRNA were decreased in the oolong tea extract-treated cells. We also investigated the inhibitory effects of oolong tea on the pigmentation induced by ultraviolet B (UVB) by using brownish guinea pigs in vivo. The number of 3,4-dihydroxyphenylalanine (DOPA)-positive melanocytes increased by UVB was repressed by an oral administration of oolong tea. These results imply that oolong tea might be effective in whitening and that its inhibitory effect on melanogenesis was involved in the decrease of intracellular tyrosinase at the mRNA level.

  13. Monascus pigments.

    PubMed

    Feng, Yanli; Shao, Yanchun; Chen, Fusheng

    2012-12-01

    Monascus pigments (MPs) as natural food colorants have been widely utilized in food industries in the world, especially in China and Japan. Moreover, MPs possess a range of biological activities, such as anti-mutagenic and anticancer properties, antimicrobial activities, potential anti-obesity activities, and so on. So, in the past two decades, more and more attention has been paid to MPs. Up to now, more than 50 MPs have been identified and studied. However, there have been some reviews about red fermented rice and the secondary metabolites produced by Monascus, but no monograph or review of MPs has been published. This review covers the categories and structures, biosynthetic pathway, production, properties, detection methods, functions, and molecular biology of MPs.

  14. Definition of an automated Content-Based Image Retrieval (CBIR) system for the comparison of dermoscopic images of pigmented skin lesions

    PubMed Central

    Baldi, Alfonso; Murace, Raffaele; Dragonetti, Emanuele; Manganaro, Mario; Guerra, Oscar; Bizzi, Stefano; Galli, Luca

    2009-01-01

    Background New generations of image-based diagnostic machines are based on digital technologies for data acquisition; consequently, the diffusion of digital archiving systems for diagnostic exams preservation and cataloguing is rapidly increasing. To overcome the limits of current state of art text-based access methods, we have developed a novel content-based search engine for dermoscopic images to support clinical decision making. Methods To this end, we have enrolled, from 2004 to 2008, 3415 caucasian patients and collected 24804 dermoscopic images corresponding to 20491 pigmented lesions with known pathology. The images were acquired with a well defined dermoscopy system and stored to disk in 24-bit per pixel TIFF format using interactive software developed in C++, in order to create a digital archive. Results The analysis system of the images consists in the extraction of the low-level representative features which permits the retrieval of similar images in terms of colour and texture from the archive, by using a hierarchical multi-scale computation of the Bhattacharyya distance of all the database images representation with respect to the representation of user submitted (query). Conclusion The system is able to locate, retrieve and display dermoscopic images similar in appearance to one that is given as a query, using a set of primitive features not related to any specific diagnostic method able to visually characterize the image. Similar search engine could find possible usage in all sectors of diagnostic imaging, or digital signals, which could be supported by the information available in medical archives. PMID:19682395

  15. An intracellular anion channel critical for pigmentation.

    PubMed

    Bellono, Nicholas W; Escobar, Iliana E; Lefkovith, Ariel J; Marks, Michael S; Oancea, Elena

    2014-12-16

    Intracellular ion channels are essential regulators of organellar and cellular function, yet the molecular identity and physiological role of many of these channels remains elusive. In particular, no ion channel has been characterized in melanosomes, organelles that produce and store the major mammalian pigment melanin. Defects in melanosome function cause albinism, characterized by vision and pigmentation deficits, impaired retinal development, and increased susceptibility to skin and eye cancers. The most common form of albinism is caused by mutations in oculocutaneous albinism II (OCA2), a melanosome-specific transmembrane protein with unknown function. Here we used direct patch-clamp of skin and eye melanosomes to identify a novel chloride-selective anion conductance mediated by OCA2 and required for melanin production. Expression of OCA2 increases organelle pH, suggesting that the chloride channel might regulate melanin synthesis by modulating melanosome pH. Thus, a melanosomal anion channel that requires OCA2 is essential for skin and eye pigmentation.

  16. Exosomes released by keratinocytes modulate melanocyte pigmentation

    PubMed Central

    Cicero, Alessandra Lo; Delevoye, Cédric; Gilles-Marsens, Floriane; Loew, Damarys; Dingli, Florent; Guéré, Christelle; André, Nathalie; Vié, Katell; van Niel, Guillaume; Raposo, Graça

    2015-01-01

    Cells secrete extracellular vesicles (EVs), exosomes and microvesicles, which transfer proteins, lipids and RNAs to regulate recipient cell functions. Skin pigmentation relies on a tight dialogue between keratinocytes and melanocytes in the epidermis. Here we report that exosomes secreted by keratinocytes enhance melanin synthesis by increasing both the expression and activity of melanosomal proteins. Furthermore, we show that the function of keratinocyte-derived exosomes is phototype-dependent and is modulated by ultraviolet B. In sum, this study uncovers an important physiological function for exosomes in human pigmentation and opens new avenues in our understanding of how pigmentation is regulated by intercellular communication in both healthy and diseased states. PMID:26103923

  17. Exosomes released by keratinocytes modulate melanocyte pigmentation.

    PubMed

    Lo Cicero, Alessandra; Delevoye, Cédric; Gilles-Marsens, Floriane; Loew, Damarys; Dingli, Florent; Guéré, Christelle; André, Nathalie; Vié, Katell; van Niel, Guillaume; Raposo, Graça

    2015-06-24

    Cells secrete extracellular vesicles (EVs), exosomes and microvesicles, which transfer proteins, lipids and RNAs to regulate recipient cell functions. Skin pigmentation relies on a tight dialogue between keratinocytes and melanocytes in the epidermis. Here we report that exosomes secreted by keratinocytes enhance melanin synthesis by increasing both the expression and activity of melanosomal proteins. Furthermore, we show that the function of keratinocyte-derived exosomes is phototype-dependent and is modulated by ultraviolet B. In sum, this study uncovers an important physiological function for exosomes in human pigmentation and opens new avenues in our understanding of how pigmentation is regulated by intercellular communication in both healthy and diseased states.

  18. The focal differentiation of pigment cells.

    PubMed

    Whimster, I W

    1979-05-01

    A study has been made of the normal development and of the regeneration after excision of the groups of large pigment cells which form the spotted skin pattern of the gecko Eublepharis macularius, together with the effects of neonatal graft transplantation on this pattern. The results all indicate strongly that such groups of specialized pigment cells are not clones but the product of an induction process. This is then compared with the neural reflex mechanism by which the skin pattern of Chamaeoleo dilepis is formed.

  19. Predicting Phenotype from Genotype: Normal Pigmentation*

    PubMed Central

    Valenzuela, Robert K.; Henderson, Miquia S.; Walsh, Monica H.; Garrison, Nanibaa’A.; Kelch, Jessica T.; Cohen-Barak, Orit; Erickson, Drew T.; Meaney, F. John; Walsh, J. Bruce; Cheng, Keith C.; Ito, Shosuke; Wakamatsu, Kazumasa; Frudakis, Tony; Thomas, Matthew; Brilliant, Murray H.

    2013-01-01

    Genetic information in forensic studies is largely limited to CODIS data and the ability to match samples and assign them to an individual. However, there are circumstances, in which a given DNA sample does not match anyone in the CODIS database, and no other information about the donor is available. In this study, we determined 75 SNPs in 24 genes (previously implicated in human or animal pigmentation studies) for the analysis of single- and multi-locus associations with hair, skin, and eye color in 789 individuals of various ethnic backgrounds. Using multiple linear regression modeling, five SNPs in five genes were found to account for large proportions of pigmentation variation in hair, skin, and eyes in our across-population analyses. Thus, these models may be of predictive value to determine an individual’s pigmentation type from a forensic sample, independent of ethnic origin. PMID:20158590

  20. Diagnosis and management of facial pigmented macules.

    PubMed

    Lallas, Aimilios; Argenziano, Giuseppe; Moscarella, Elvira; Longo, Caterina; Simonetti, Vito; Zalaudek, Iris

    2014-01-01

    The differential diagnosis of pigmented macules on the mottled chronic sun-damaged skin of the face is challenging and includes lentigo maligna (LM), pigmented actinic (solar) keratosis, solar lentigo, and lichen-planus-like keratosis. Although dermatoscopy improves the diagnostic accuracy of the unaided eye, the accurate diagnosis and management of pigmented facial macules remains one of the most challenging scenarios in daily practice. This is related to the fact that pigmented actinic (solar) keratosis, lichen-planus-like keratosis, and LM may reveal overlapping criteria, making their differential diagnosis clinically difficult. For this reason, practical rules have been introduced, which should help to minimize the risk for inappropriate diagnosis and management of LM.

  1. Pigments of fly agaric (Amanita muscaria).

    PubMed

    Stintzing, Florian; Schliemann, Willibald

    2007-01-01

    The complex pigment pattern of fly agaric (Amanita muscaria) cap skins has been studied by LC-DAD and mass spectrometry. Among the betaxanthins the corresponding derivatives of serine, threonine, ethanolamine, alanine, Dopa, phenylalanine and tryptophan are reported for the first time to contribute to the pigment pattern of fly agarics. Betalamic acid, the chromophoric precursor of betaxanthins and betacyanins, muscaflavin and seco-dopas were also detected. Furthermore, the red-purple muscapurpurin and the red muscarubrin were tentatively assigned while further six betacyanin-like components could not be structurally allocated. Stability studies indicated a high susceptibility of pigment extracts to degradation which led to rapid colour loss thus rendering a complete characterization of betacyanin-like compounds impossible at present. Taking into account these difficulties the presented results may be a starting point for a comprehensive characterization of the pigment composition of fly agarics.

  2. Human pigmentation genes under environmental selection

    PubMed Central

    2012-01-01

    Genome-wide association studies and comparative genomics have established major loci and specific polymorphisms affecting human skin, hair and eye color. Environmental changes have had an impact on selected pigmentation genes as populations have expanded into different regions of the globe. PMID:23110848

  3. Surgical Management of Iatrogenic Pigment Dispersion Glaucoma

    PubMed Central

    Mierlo, Camille Van; Pinto, Luis Abegão

    2015-01-01

    ABSTRACT Introduction: Iatrogenic pigment dispersion syndrome generally originates from a repetitive, mechanical trauma to the pigmented posterior epithelium of the iris. This trauma can arise after intraocular surgery, most commonly due to an abnormal contact between the intraocular lens (IOL) and the iris. Whether surgical removal of this primary insult can lead to a successful intraocular pressure (IOP) control remains unclear. Methods: Case-series. Patients with IOP elevation and clinical signs of pigment dispersion were screened for a diagnosis of iatrogenic IOL-related pigment dispersion. Results: Three patients in which the IOL or the IOL-bag complex caused a pigment dispersion through a repetitive iris chafing were selected. In two cases, replacement of a sulcus-based single-piece IOL (patient 1) or a sub-luxated in-the-bag IOL (patient 2) by an anterior-chamber (AC) iris-fixed IOL led to a sustained decrease in IOP. In the third case, extensive iris atrophy and poor anatomical AC parameters for IOL implantation precluded further surgical intervention. Conclusion: IOL-exchange appears to be a useful tool in the management of iatrogenic pigment dispersion glaucoma due to inappropriate IOL implantation. This cause-oriented approach seems to be effective in controlling IOP, but should be offered only if safety criteria are met. How to cite this article: Van Mierlo C, Abegao Pinto L, Stalmans I. Surgical Management of Iatrogenic Pigment Dispersion Glaucoma. J Curr Glaucoma Pract 2015;9(1):28-32. PMID:26997830

  4. Alveolar abnormalities

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/001093.htm Alveolar abnormalities To use the sharing features on this page, please enable JavaScript. Alveolar abnormalities are changes in the tiny air sacs in ...

  5. Nail abnormalities

    MedlinePlus

    Beau's lines; Fingernail abnormalities; Spoon nails; Onycholysis; Leukonychia; Koilonychia; Brittle nails ... 2012:chap 71. Zaiac MN, Walker A. Nail abnormalities associated with systemic pathologies. Clin Dermatol . 2013;31: ...

  6. Oral pigmentation: A review.

    PubMed

    Sreeja, C; Ramakrishnan, K; Vijayalakshmi, D; Devi, M; Aesha, I; Vijayabanu, B

    2015-08-01

    Pigmentations are commonly found in the mouth. They represent in various clinical patterns that can range from just physiologic changes to oral manifestations of systemic diseases and malignancies. Color changes in the oral mucosa can be attributed to the deposition of either endogenous or exogenous pigments as a result of various mucosal diseases. The various pigmentations can be in the form of blue/purple vascular lesions, brown melanotic lesions, brown heme-associated lesions, gray/black pigmentations.

  7. Oral pigmentation: A review

    PubMed Central

    Sreeja, C.; Ramakrishnan, K.; Vijayalakshmi, D.; Devi, M.; Aesha, I.; Vijayabanu, B.

    2015-01-01

    Pigmentations are commonly found in the mouth. They represent in various clinical patterns that can range from just physiologic changes to oral manifestations of systemic diseases and malignancies. Color changes in the oral mucosa can be attributed to the deposition of either endogenous or exogenous pigments as a result of various mucosal diseases. The various pigmentations can be in the form of blue/purple vascular lesions, brown melanotic lesions, brown heme-associated lesions, gray/black pigmentations. PMID:26538887

  8. Potato development and skin set in fresh market red varieties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A bright, attractive, uniformly pigmented skin is critically important for fresh market red-skinned potatoes. We will summarize what is known about the potato skin development, with an emphasis on pigment accumulation and loss. We will provide some insight into what may be responsible for changes in...

  9. Quantification method for the appearance of melanin pigmentation using independent component analysis

    NASA Astrophysics Data System (ADS)

    Ojima, Nobutoshi; Okiyama, Natsuko; Okaguchi, Saya; Tsumura, Norimichi; Nakaguchi, Toshiya; Hori, Kimihiko; Miyake, Yoichi

    2005-04-01

    In the cosmetics industry, skin color is very important because skin color gives a direct impression of the face. In particular, many people suffer from melanin pigmentation such as liver spots and freckles. However, it is very difficult to evaluate melanin pigmentation using conventional colorimetric values because these values contain information on various skin chromophores simultaneously. Therefore, it is necessary to extract information of the chromophore of individual skins independently as density information. The isolation of the melanin component image based on independent component analysis (ICA) from a single skin image was reported in 2003. However, this technique has not developed a quantification method for melanin pigmentation. This paper introduces a quantification method based on the ICA of a skin color image to isolate melanin pigmentation. The image acquisition system we used consists of commercially available equipment such as digital cameras and lighting sources with polarized light. The images taken were analyzed using ICA to extract the melanin component images, and Laplacian of Gaussian (LOG) filter was applied to extract the pigmented area. As a result, for skin images including those showing melanin pigmentation and acne, the method worked well. Finally, the total amount of extracted area had a strong correspondence to the subjective rating values for the appearance of pigmentation. Further analysis is needed to recognize the appearance of pigmentation concerning the size of the pigmented area and its spatial gradation.

  10. Overview of plant pigments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chlorophylls, carotenoids, flavonoids and betalains are four major classes of biological pigments produced in plants. Chlorophylls are the primary pigments responsible for plant green and photosynthesis. The other three are accessary pigments and secondary metabolites that yield non-green colors and...

  11. A melanosomal two-pore sodium channel regulates pigmentation

    PubMed Central

    Bellono, Nicholas W.; Escobar, Iliana E.; Oancea, Elena

    2016-01-01

    Intracellular organelles mediate complex cellular functions that often require ion transport across their membranes. Melanosomes are organelles responsible for the synthesis of the major mammalian pigment melanin. Defects in melanin synthesis result in pigmentation defects, visual deficits, and increased susceptibility to skin and eye cancers. Although genes encoding putative melanosomal ion transporters have been identified as key regulators of melanin synthesis, melanosome ion transport and its contribution to pigmentation remain poorly understood. Here we identify two-pore channel 2 (TPC2) as the first reported melanosomal cation conductance by directly patch-clamping skin and eye melanosomes. TPC2 has been implicated in human pigmentation and melanoma, but the molecular mechanism mediating this function was entirely unknown. We demonstrate that the vesicular signaling lipid phosphatidylinositol bisphosphate PI(3,5)P2 modulates TPC2 activity to control melanosomal membrane potential, pH, and regulate pigmentation. PMID:27231233

  12. 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.

  13. 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.

  14. Pigmented Skin Lesions Classification Using Dermatoscopic Images

    NASA Astrophysics Data System (ADS)

    Capdehourat, Germán; Corez, Andrés; Bazzano, Anabella; Musé, Pablo

    In this paper we propose a machine learning approach to classify melanocytic lesions in malignant and benign from dermatoscopic images. The image database is composed of 433 benign lesions and 80 malignant melanoma. After an image pre-processing stage that includes hair removal filtering, each image is automatically segmented using well known image segmentation algorithms. Then, each lesion is characterized by a feature vector that contains shape, color and texture information, as well as local and global parameters that try to reflect structures used in medical diagnosis. The learning and classification stage is performed using AdaBoost.M1 with C4.5 decision trees. For the automatically segmented database, classification delivered a false positive rate of 8.75% for a sensitivity of 95%. The same classification procedure applied to manually segmented images by an experienced dermatologist yielded a false positive rate of 4.62% for a sensitivity of 95%.

  15. Iris pigment epithelial cysts in a newborn

    PubMed Central

    Zargar, Shabnam; Prendiville, Kevin John; Martinez, Eladio

    2016-01-01

    Purpose: We report a case of iris pigment epithelial cysts in a newborn and discuss the importance of an accurate diagnosis for prevention of amblyopia. Methods: We describe a case of an abnormal red reflex seen on a newborn exam. Results: A full-term female born via normal spontaneous vaginal delivery without any complications was seen in the newborn nursery. She was noted to have an abnormal eye exam. Pupils were large with circular dark excrescences of the iris pigment epithelium. She was referred to a pediatric ophthalmologist where she was noted to fixate and follow faces. No afferent pupillary defect was seen. OD red reflex was normal whereas OS red reflex was blocked mostly by dark excrescences. A 2–3 mm dark brown lesion was seen in the OD iris and a 3–5 mm dark brown lesion was seen in the OS iris, consistent with a pupillary iris pigment epithelial cyst. Central visual axis was clear OU. Glaucoma was not present and patching was not performed. Observations and clinical photographs were recommended with follow-up in three months. Conclusion: Iris pigment epithelial cysts are uncommonly seen in children. The primary care provider first seeing a newborn must be aware of lesions obscuring a red reflex with appropriate follow-up. Follow-up in three months with IOP measurements is recommended. Iris pigment epithelial cysts in children may be a cause of amblyopia, thus prompt evaluation is important for prognostic purposes and the prevention of amblyopia. PMID:27625966

  16. Depigmented Skin and Phantom Color Measurements for Realistic Prostheses

    PubMed Central

    Tanner, Paul; Leachman, Sancy; Boucher, Kenneth; Ozçelik, Tunçer Burak

    2013-01-01

    Purpose The purpose of this study was to test the hypothesis that regardless of human skin phototype, areas of depigmented skin, as seen in vitiligo, are optically indistinguishable among skin phototypes. The average of the depigmented skin measurements can be used to develop the base color of realistic prostheses. Methods and Materials Data from 20 of 32 recruited vitiligo study participants. Diffuse reflectance spectroscopy measurements were made from depigmented skin and adjacent pigmented skin, then compared to 66 pigmented polydimethylsiloxane phantoms to determine pigment concentrations in turbid media for making realistic facial prostheses. Results The Area Under spectral intensity Curve (AUC) was calculated for average spectroscopy measurements of pigmented sites in relation to skin phototype (p=0.0505) and depigmented skin in relation to skin phototype (p=0.59). No significant relationship exists between skin phototypes and depigmented skin spectroscopy measurements. The average of the depigmented skin measurements (AUC 19,129) was the closest match to phantom 6.4 (AUC 19,162) Conclusions Areas of depigmented skin are visibly indistinguishable per skin phototype, yet spectrometry shows that depigmented skin measurements varied and were unrelated to skin phototype. Possible sources of optical variation of depigmented skin include age, body site, blood flow, quantity/quality of collagen, and other chromophores. The average of all depigmented skin measurements can be used to derive the pigment composition and concentration for realistic facial prostheses. PMID:23750920

  17. Molecular mechanisms of green tea polyphenols with protective effects against skin photoaging.

    PubMed

    Roh, Eunmiri; Kim, Jong-Eun; Kwon, Jung Yeon; Park, Jun Seong; Bode, Ann M; Dong, Zigang; Lee, Ki Won

    2017-05-24

    Whereas green tea has historically been consumed in high quantities in Northeast Asia, its popularity is also increasing in many Western countries. Green tea is an abundant source of plant polyphenols exhibiting numerous effects that are potentially beneficial for human health. Accumulating evidence suggests that green tea polyphenols confer protective effects on the skin against ultraviolet (UV) irradiation-induced acceleration of skin aging, involving antimelanogenic, antiwrinkle, antioxidant, and anti-inflammatory effects as well as prevention of immunosuppression. Melanin pigmentation in the skin is a major defense mechanism against UV irradiation, but pigmentation abnormalities such as melasma, freckles, senile lentigines, and other forms of melanin hyperpigmentation can also cause serious health and aesthetic issues. Furthermore, UV irradiation initiates the degradation of fibrillar collagen and elastic fibers, promoting the process of skin aging through deep wrinkle formation and loss of tissue elasticity. UV irradiation-induced formation of free radicals also contributes to accelerated photoaging. Additionally, immunosuppression caused by UV irradiation plays an important role in photoaging and skin carcinogenesis. In this review, we summarize the current literature regarding the antimelanogenic, antiwrinkle, antioxidant, and immunosuppression preventive mechanisms of green tea polyphenols that have been demonstrated to protect against UV irradiation-stimulated skin photoaging, and gauge the quality of evidence supporting the need for clinical studies using green tea polyphenols as anti-photoaging agents in novel cosmeceuticals.

  18. Macular pigment and lutein supplementation in choroideremia.

    PubMed

    Duncan, Jacque L; Aleman, Tomas S; Gardner, Leigh M; De Castro, Elaine; Marks, Daniel A; Emmons, Jessica M; Bieber, Michelle L; Steinberg, Janet D; Bennett, Jean; Stone, Edwin M; MacDonald, Ian M; Cideciyan, Artur V; Maguire, Maureen G; Jacobson, Samuel G

    2002-03-01

    Choroideremia is an incurable X-linked retinal degeneration caused by mutations in the gene encoding Rab escort protein-1. A group of clinically defined and genotyped patients were studied to determine: (1) the degree of rod and cone dysfunction and structural abnormality in the central retina and the level of macular pigment; and (2) the response of macular pigment and foveal vision to a 6 month trial of supplementation with oral lutein (at 20 mg per day). Rod and cone-mediated function was measured with dark-adapted static perimetry; in vivo retinal structure was determined with optical coherence tomography; and macular pigment optical density was measured with heterochromatic flicker photometry. In this cohort of patients (ages 15-65 years), both rod- and cone-mediated central function declined with age as did central retinal thickness. Macular pigment levels did not differ between patients and male control subjects. Supplementation of oral lutein in a subset of patients led to an increase in serum lutein and macular pigment levels; absolute foveal sensitivity did not change. It is concluded that macular pigment density can be augmented by oral intake of lutein in patients with choroideremia. There was no short-term change in the central vision of the patients on the supplement, but long-term influences of lutein supplementation on disease natural history warrant further study.

  19. Genetics of pigmentation and melanoma predisposition.

    PubMed

    Pho, L N; Leachman, S A

    2010-02-01

    About 5-10% of human cutaneous malignant melanoma is hereditary and known to involve rare germline mutations in highly penetrant, autosomal dominant genes. These genes are important in cell cycle control but are not responsible for all familial cases of melanoma. Epidemiologic studies have linked specific phenotypic traits including fair skin, light-colored eyes, and poor tanning ability to melanoma risks. The ability to visually discern and define pigmentary phenotypes in humans and in animal models has permitted elucidation of many genes involved in pigmentation and melanin biosynthesis. Additional genetic epidemiological studies have recently identified a subset of these pigmentation genes that are associated with risk for melanoma and other cutaneous malignancies as well as photosensitivity. Genome-wide association studies (GWAS) have unveiled single nucleotide polymorphisms (SNPs) or genetic variants in MC1R, TPCN2, ASIP, KITLG, NCKX5, TYR, IRF4, OCA2, and TYRP1 pigmentation genes. These findings emphasize the contribution of pigmentation pathways to melanoma predisposition and tumorigenesis through gene-environment interactions. Since pigmentation genes in the melanin synthesis pathway also confer risk for cutaneous malignancy, a better understanding of the operative molecular mechanisms involved in this relationship has the potential to impact individual risk assessment for cutaneous malignant melanoma in the future. This paper is an overview of our current understanding of pigmentation gene modifications that have been associated with melanoma risk and how these genes can enrich clinical management, prevention, and early detection of malignant melanoma.

  20. Abnormal ultraviolet mutagenic spectrum in plasmid DNA replicated in cultured fibroblasts from a patient with the skin cancer-prone disease, xeroderma pigmentosum

    SciTech Connect

    Seetharam, S.; Protic-Sabljic, M.; Seidman, M.M.; Kraemer, K.H.

    1987-12-01

    A shuttle vector plasmid, pZ189, was utilized to assess the types of mutations that cells from a patient with xeroderma pigmentosum, complementation group D, introduce into ultraviolet (UV) damaged, replicating DNA. Patients with xeroderma pigmentosum have clinical and cellular UV hypersensitivity, increased frequency of sun-induced skin cancer, and deficient DNA repair. In comparison to UV-treated pZ189 replicated in DNA repair-proficient cells, there were fewer surviving plasmids, a higher frequency of plasmids with mutations, fewer plasmids with two or more mutations in the marker gene, and a new mutagenic hotspot. The major type of base substitution mutation was the G:C to A:T transition with both cell lines. These results, together with similar findings published earlier with cells from a xeroderma pigmentosum patient in complementation group A, suggest that isolated G:C to A:T somatic mutations may be particularly important in generation of human skin cancer by UV radiation.

  1. Meiotic abnormalities

    SciTech Connect

    1993-12-31

    Chapter 19, describes meiotic abnormalities. These include nondisjunction of autosomes and sex chromosomes, genetic and environmental causes of nondisjunction, misdivision of the centromere, chromosomally abnormal human sperm, male infertility, parental age, and origin of diploid gametes. 57 refs., 2 figs., 1 tab.

  2. Ectodermal dysplasia and abnormal thumbs.

    PubMed

    Lucky, A W; Esterly, N B; Tunnessen, W W

    1980-05-01

    Two unrelated children, a girl and a boy, with alopecia, anomalous cutaneous pigmentation, abnormal thumbs, and endocrine disorders, including short stature and delayed bone age in one patient and juvenile onset diabetes mellitus in the other, are described. In one instance, the mother and the maternal grandmother had similar abnormalities, although of a less severe nature. Both children had normal nails and no unusual susceptibility to infections. We believe these two patients represent a previously undescribed syndrome of ectodermal dysplasia that may be inherited as an autosomal-dominant trait.

  3. Lymphoblastoid lines and skin fibroblasts from patients with tuberous sclerosis are abnormally sensitive to ionizing radiation and to a radiomimetic chemical

    SciTech Connect

    Scudiero, D.A.; Moshell, A.N.; Scarpinato, R.G.; Meyer, S.A.; Clatterbuck, B.E.; Tarone, R.E.; Robbins, J.H.

    1982-03-01

    Lymphoblastoid lines, derived by transforming peripheral blood lymphocytes with Epstein-Barr virus, and skin fibroblast lines were established from two patients with tuberous sclerosis. The number of viable lymphoblastoid cells was determined by their ability to exclude the vital dye trypan blue after their irradiation with x-rays or 254 nm ultraviolet light. The growth of fibroblasts was determined by their ability to form colonies after treatment with the radiomimetic, DNA-damaging chemical N-methyl-N'-nitro-N-nitrosoguanidine. The tuberous sclerosis lymphoblastoid lines were hypersensitive to x-rays but had normal sensitivity to the ultraviolet radiation. The tuberous sclerosis fibroblast lines were hypersensitive to the N-methyl-N'-nitro-N-nitrosoguanidine. The hypersensitivity of tuberous sclerosis cells to x-rays and to N-methyl-N'-nitro-N-nitrosoguanidine is believed to reflect defective repair of DNA damaged by these agents and may provide the basis for in vitro, including prenatal, diagnostic tests for tuberous sclerosis.

  4. RGB mapping of hemoglobin distribution in skin

    NASA Astrophysics Data System (ADS)

    Jakovels, Dainis; Spigulis, Janis; Rogule, Laura

    2011-07-01

    An experimental RGB imaging system based on commercial color camera was constructed, and its potential for mapping of hemoglobin distribution in skin was studied. Two types of LEDs (RGB and white "warm" LEDs) were compared as illuminators for acquiring images of vascular and pigmented skin malformations. A novel approach for studies of skin capillary refill by RGB analysis has been proposed and discussed.

  5. Pigmented basal cell carcinoma mimicking a superficial spreading melanoma.

    PubMed

    Hasbún Acuña, Paula; Cullen Aravena, Roberto; Maturana Donaire, César; Ares Mora, Raúl; Porras Kusmanic, Ninoska

    2016-12-20

    Basal cell carcinoma is the most common form of skin cancer, especially in elderly people. Pigmented basal cell carcinoma is a rare subtype and has been described in the literature as a nodular and hyperpigmented lesion; rarely, it can appear as an extensive pigmented plate, which may be clinically indistinguishable from superficial spreading melanoma and Bowen disease. Dermatoscopy has a high sensitivity in the diagnosis of basal cell carcinoma. When Menzies criteria are used; however, the final diagnosis is made by histopathology. The objective of the present report is to analyze the case of a patient with pigmented basal cell carcinoma simulating a superficial spreading melanoma.

  6. [Skin and sun exposure].

    PubMed

    Cannavò, Serafinella Patrizia; Borgia, Francesco; Trifirò, Caterina; Aragona, Emanuela

    2013-01-01

    Fisherman commonly experience a significant number of cutaneous problems, related to the exposure to environmental factors due to their working conditions. Among these factors, sun exposure is able to determine both acute and chronic skin damage, mostly linked to the effects of the ultraviolet (UV) radiation on epidermal and dermal structures. In particular, UV-A appears to play a major role in the deterioration of dermal structure leading to the photoaged appearance of the skin, while UV-B is mainly responsible for skin cancers. Peculiar clinical features of skin damage in fishermen include dryness, irregular pigmentation, wrinkling, stellate pseudoscars, elastosis, inelasticity, telangiectasia, comedones and sebaceous hyperplasia. Furtheremore, the high incidence of non-melanoma skin cancers, on sun-exposed areas, confirms the need for occupational health policies focusing on issues such as photoprotection.

  7. Epidermal gene expression and ethnic pigmentation variations among individuals of Asian, European and African ancestry.

    PubMed

    Yin, Lanlan; Coelho, Sergio G; Ebsen, Dominik; Smuda, Christoph; Mahns, Andre; Miller, Sharon A; Beer, Janusz Z; Kolbe, Ludger; Hearing, Vincent J

    2014-10-01

    Differences in visible skin pigmentation give rise to the wide variation of skin colours seen in racial/ethnic populations. Skin pigmentation is important not only from cosmetic and psychological points of view, but more importantly because of its implications for the risk of all types of skin cancers, on photoaging, etc. Despite differences in those parameters in Caucasian and Asian skin types, they are remarkably similar in their production and distribution of melanins, and the mechanism(s) underlying their different characteristics have remained obscure. In this study, we used microarray analysis of skin suction blisters to investigate molecular differences underlying the determination of pigmentation in various skin types, and we used immunohistochemistry to validate the expression patterns of several interesting targets that were identified. Intriguingly, Caucasian and Asian skins had highly similar gene expression patterns that differed significantly from the pattern of African skin. The results of this study suggest the dynamic interactions of different types of cells in human skin that regulate its pigmentation, reveal that the known pigmentation genes have a limited contribution and uncover a new array of genes, including NINL and S100A4, that might be involved in that regulation.

  8. Effect of epidermal pigmentation on selective vascular effects of pulsed laser

    SciTech Connect

    Tan, O.T.; Kerschmann, R.; Parrish, J.A.

    1984-01-01

    The effect of epidermal pigmentation on the threshold exposure dose for inducing purpura with a tunable dye laser at 577 nm, 1.5 microseconds pulse duration, was studied in 21 human volunteers with varied genetically determined amounts of melanin. More laser energy was required to produce purpura as constitutive skin pigmentation increased. Histology showed that, in lighter skin, the laser threshold dose produced the most specific vascular injury with no disruption of surrounding structures. In more pigmented skin, damage occurred in the epidermal basal layer and very few changes were seen in blood vessels below.

  9. Skin Dictionary

    MedlinePlus

    ... your skin, hair, and nails Skin dictionary Camp Discovery Good Skin Knowledge lesson plans and activities Video library Find a ... your skin, hair, and nails Skin dictionary Camp Discovery Good Skin Knowledge lesson plans and activities Video library Find a ...

  10. Leukocyte abnormalities.

    PubMed

    Gabig, T G

    1980-07-01

    Certain qualitative abnormalities in neutrophils and blood monocytes are associated with frequent, severe, and recurrent bacterial infections leading to fatal sepsis, while other qualitative defects demonstrated in vitro may have few or no clinical sequelae. These qualitative defects are discussed in terms of the specific functions of locomotion, phagocytosis, degranulation, and bacterial killing.

  11. The Hunt for Natural Skin Whitening Agents

    PubMed Central

    Smit, Nico; Vicanova, Jana; Pavel, Stan

    2009-01-01

    Skin whitening products are commercially available for cosmetic purposes in order to obtain a lighter skin appearance. They are also utilized for clinical treatment of pigmentary disorders such as melasma or postinflammatory hyperpigmentation. Whitening agents act at various levels of melanin production in the skin. Many of them are known as competitive inhibitors of tyrosinase, the key enzyme in melanogenesis. Others inhibit the maturation of this enzyme or the transport of pigment granules (melanosomes) from melanocytes to surrounding keratinocytes. In this review we present an overview of (natural) whitening products that may decrease skin pigmentation by their interference with the pigmentary processes. PMID:20054473

  12. Internal pigment cells respond to external UV radiation in frogs.

    PubMed

    Franco-Belussi, Lilian; Nilsson Sköld, Helen; de Oliveira, Classius

    2016-05-01

    Fish and amphibians have pigment cells that generate colorful skins important for signaling, camouflage, thermoregulation and protection against ultraviolet radiation (UVR). However, many animals also have pigment cells inside their bodies, on their internal organs and membranes. In contrast to external pigmentation, internal pigmentation is remarkably little studied and its function is not well known. Here, we tested genotoxic effects of UVR and its effects on internal pigmentation in a neotropical frog, Physalaemus nattereri We found increases in body darkness and internal melanin pigmentation in testes and heart surfaces and in the mesenterium and lumbar region after just a few hours of UVR exposure. The melanin dispersion in melanomacrophages in the liver and melanocytes in testes increased after UV exposure. In addition, the amount of melanin inside melanomacrophages cells also increased. Although mast cells were quickly activated by UVR, only longer UVR exposure resulted in genotoxic effects inside frogs, by increasing the frequency of micronuclei in red blood cells. This is the first study to describe systemic responses of external UVR on internal melanin pigmentation, melanomacrophages and melanocytes in frogs and thus provides a functional explanation to the presence of internal pigmentation.

  13. Photosynthetic Pigments in Diatoms

    PubMed Central

    Kuczynska, Paulina; Jemiola-Rzeminska, Malgorzata; Strzalka, Kazimierz

    2015-01-01

    Photosynthetic pigments are bioactive compounds of great importance for the food, cosmetic, and pharmaceutical industries. They are not only responsible for capturing solar energy to carry out photosynthesis, but also play a role in photoprotective processes and display antioxidant activity, all of which contribute to effective biomass and oxygen production. Diatoms are organisms of a distinct pigment composition, substantially different from that present in plants. Apart from light-harvesting pigments such as chlorophyll a, chlorophyll c, and fucoxanthin, there is a group of photoprotective carotenoids which includes β-carotene and the xanthophylls, diatoxanthin, diadinoxanthin, violaxanthin, antheraxanthin, and zeaxanthin, which are engaged in the xanthophyll cycle. Additionally, some intermediate products of biosynthetic pathways have been identified in diatoms as well as unusual pigments, e.g., marennine. Marine algae have become widely recognized as a source of unique bioactive compounds for potential industrial, pharmaceutical, and medical applications. In this review, we summarize current knowledge on diatom photosynthetic pigments complemented by some new insights regarding their physico-chemical properties, biological role, and biosynthetic pathways, as well as the regulation of pigment level in the cell, methods of purification, and significance in industries. PMID:26389924

  14. Photosynthetic Pigments in Diatoms.

    PubMed

    Kuczynska, Paulina; Jemiola-Rzeminska, Malgorzata; Strzalka, Kazimierz

    2015-09-16

    Photosynthetic pigments are bioactive compounds of great importance for the food, cosmetic, and pharmaceutical industries. They are not only responsible for capturing solar energy to carry out photosynthesis, but also play a role in photoprotective processes and display antioxidant activity, all of which contribute to effective biomass and oxygen production. Diatoms are organisms of a distinct pigment composition, substantially different from that present in plants. Apart from light-harvesting pigments such as chlorophyll a, chlorophyll c, and fucoxanthin, there is a group of photoprotective carotenoids which includes β-carotene and the xanthophylls, diatoxanthin, diadinoxanthin, violaxanthin, antheraxanthin, and zeaxanthin, which are engaged in the xanthophyll cycle. Additionally, some intermediate products of biosynthetic pathways have been identified in diatoms as well as unusual pigments, e.g., marennine. Marine algae have become widely recognized as a source of unique bioactive compounds for potential industrial, pharmaceutical, and medical applications. In this review, we summarize current knowledge on diatom photosynthetic pigments complemented by some new insights regarding their physico-chemical properties, biological role, and biosynthetic pathways, as well as the regulation of pigment level in the cell, methods of purification, and significance in industries.

  15. Skin Diseases: Skin Health and Skin Diseases

    MedlinePlus

    Skip Navigation Bar Home Current Issue Past Issues Skin Diseases Skin Health and Skin Diseases Past Issues / Fall 2008 Table of Contents ... acne to wrinkles Did you know that your skin is the largest organ of your body? It ...

  16. UV ADAPTATION; pigmentation and protection against overexposure.

    PubMed

    de Gruijl, Frank R

    2017-03-07

    The skin is known to adapt to UV exposures, i.e., become less sensitive to sunburn. Reported decreases in sensitivity vary widely from well over 10 fold down to a negligible 10%. This appears to depend importantly on the UV irradiation spectrum to which the skin adapts and on the UV irradiation spectrum that is used to test the sensitivity. The sensitivity is conventionally and generally assessed by the reciprocal of the minimal erythema dose (MED): the UV dose causing a just perceptible reddening of the skin after 8 - 24 h. However, MED is much too subtle for everyday life: people will not notice a minimal reddening and commonly consider themselves sunburnt at considerably higher UV doses causing an intense reddening. Levels of adaptation of a well-tanned skin may be substantially higher at these more intense levels of reddening than MED levels. This expectation is based on the fact that people with a constitutively coloured skin may show moderate differences in MED with fair skinned people but far less steep increases in reddening with overexposures to solar simulated radiation (SSR). UVA exposure is known to enhance pigmentation and may thus be important in protection against overexposure to SSR. This article is protected by copyright. All rights reserved.

  17. Pigmented central neurocytoma.

    PubMed

    Kiehl, Tim-Rasmus; Kalkanis, Steven N; Louis, David N

    2004-06-01

    Central neurocytoma is a low-grade neuronal neoplasm that occurs most often within the lateral ventricles. We report the case of a 60-year-old woman who presented with gait problems, headache and memory loss. Preoperative evaluation demonstrated a heterogeneous, hypervascular and partially cystic mass in the left lateral ventricle. Histopathological examination revealed characteristic features of central neurocytoma, including immunoreactivity for synaptophysin, as well as the unusual feature of abundant pigment in the cytoplasm of tumor cells. Special stains revealed iron, consistent with hemosiderin, but found no evidence of melanin or melanosomes. Previous reports of pigmented central neurocytoma have described the presence of lipofuscin or neuromelanin. To our knowledge, the present case represents the first example of pigmented central neurocytoma secondary to hemosiderin deposition.

  18. A melanocortin 1 receptor allele suggests varying pigmentation among Neanderthals.

    PubMed

    Lalueza-Fox, Carles; Römpler, Holger; Caramelli, David; Stäubert, Claudia; Catalano, Giulio; Hughes, David; Rohland, Nadin; Pilli, Elena; Longo, Laura; Condemi, Silvana; de la Rasilla, Marco; Fortea, Javier; Rosas, Antonio; Stoneking, Mark; Schöneberg, Torsten; Bertranpetit, Jaume; Hofreiter, Michael

    2007-11-30

    The melanocortin 1 receptor (MC1R) regulates pigmentation in humans and other vertebrates. Variants of MC1R with reduced function are associated with pale skin color and red hair in humans of primarily European origin. We amplified and sequenced a fragment of the MC1R gene (mc1r) from two Neanderthal remains. Both specimens have a mutation that was not found in approximately 3700 modern humans analyzed. Functional analyses show that this variant reduces MC1R activity to a level that alters hair and/or skin pigmentation in humans. The impaired activity of this variant suggests that Neanderthals varied in pigmentation levels, potentially on the scale observed in modern humans. Our data suggest that inactive MC1R variants evolved independently in both modern humans and Neanderthals.

  19. Laser-generated acoustic wave studies on tattoo pigment

    NASA Astrophysics Data System (ADS)

    Paterson, Lorna M.; Dickinson, Mark R.; King, Terence A.

    1996-01-01

    A Q-switched alexandrite laser (180 ns at 755 nm) was used to irradiate samples of agar embedded with red, black and green tattoo dyes. The acoustic waves generated in the samples were detected using a PVDF membrane hydrophone and compared to theoretical expectations. The laser pulses were found to generate acoustic waves in the black and green samples but not in the red pigment. Pressures of up to 1.4 MPa were produced with irradiances of up to 96 MWcm-2 which is comparable to the irradiances used to clear pigment embedded in skin. The pressure gradient generated across pigment particles was approximately 1.09 X 1010 Pam-1 giving a pressure difference of 1.09 +/- 0.17 MPa over a particle with mean diameter 100 micrometers . This is not sufficient to permanently damage skin which has a tensile strength of 7.4 MPa.

  20. PIGMENT DEPOSITION IN VISCERA ASSOCIATED WITH PROLONGED CHLORPROMAZINE THERAPY.

    PubMed

    GREINER, A C; NICOLSON, G A

    1964-09-19

    Twelve physically healthy young adult mental hospital patients died unexpectedly while on prolonged chlorpromazine therapy. Five of them had clinically obvious pigmentation of the exposed skin. Two of these had impairment of vision as well. Autopsies were performed on all 12 patients. Extensive deposits of pigment (exhibiting the physical and histochemical properties of melanin) were present in macrophages in the dermis and throughout the reticuloendothelial system, and in the parenchymal cells of internal organs. The dopa tyrosinase reaction indicated increased melanocyte activity in the epidermis.The possible mechanism of production of this pigment is discussed, and the belief is expressed that the increased melanin production is due, at least partly, to the effect of chlorpromazine on the autonomic nervous system, blocking the production of pigment-lightening factors, of which melatonin is the most important. A short outline of contemplated further investigation is given.

  1. Networks and pathways in pigmentation, health, and disease.

    PubMed

    Baxter, Laura L; Loftus, Stacie K; Pavan, William J

    2009-01-01

    Extensive studies of the biology of the pigment-producing cell (melanocyte) have resulted in a wealth of knowledge regarding the genetics and developmental mechanisms governing skin and hair pigmentation. The ease of identification of altered pigment phenotypes, particularly in mouse coat color mutants, facilitated early use of the pigmentary system in mammalian genetics and development. In addition to the large collection of developmental genetics data, melanocytes are of interest because their malignancy results in melanoma, a highly aggressive and frequently fatal cancer that is increasing in Caucasian populations worldwide. The genetic programs regulating melanocyte development, function, and malignancy are highly complex and only partially understood. Current research in melanocyte development and pigmentation is revealing new genes important in these processes and additional functions for previously known individual components. A detailed understanding of all the components involved in melanocyte development and function, including interactions with neighboring cells and response to environmental stimuli, will be necessary to fully comprehend this complex system. The inherent characteristics of pigmentation biology as well as the resources available to researchers in the pigment cell community make melanocytes an ideal cell type for analysis using systems biology approaches. In this review, the study of melanocyte development and pigmentation is considered as a candidate for systems biology-based analyses.

  2. Acral peeling skin syndrome.

    PubMed

    Hashimoto, K; Hamzavi, I; Tanaka, K; Shwayder, T

    2000-12-01

    Peeling skin syndrome is a rare autosomal recessive disease characterized by widespread painless peeling of the skin in superficial sheets. We describe a 34-year-old man with a lifelong history of spontaneous asymptomatic peeling skin limited to the acral surfaces. This patient probably represents a localized variant of peeling skin syndrome, which has previously been described as a generalized condition. Light and electron microscopic studies of biopsy specimens taken before and after immersion in water were performed. It was concluded that this patient has abnormal keratohyalin granules and inadequate aggregation of keratin filaments that caused the separation of the epidermis in the stratum corneum through the clear zone. Alternatively, unknown keratin species expressed in the clear zone may also cause the abnormality. (J Am Acad Dermatol 2000;43:1112-9.).

  3. Skin Cancer

    MedlinePlus

    ... version of this page please turn Javascript on. Skin Cancer What is Skin Cancer? Skin cancer is the most common type ... of approximately 9,480 Americans in 2013. Can Skin Cancer Be Treated? Most basal cell and squamous ...

  4. Determination of pigments in vegetables.

    PubMed

    Schoefs, Benoît

    2004-10-29

    Plant pigments are responsible for the shining color of plant tissues. They are also found in animal tissues and, eventually in transformed food products as additives. These pigments have an important impact on the commercial value of products, because the colors establish the first contact with the consumer. In addition plant pigments may have an influence on the health of the consumers. Pigments are labile: they can be easily altered, and even destroyed. Analytical processes have been developed to determine pigment composition. The aim of this paper is to provide a brief overview of these methods.

  5. Terahertz Analysis of Quinacridone Pigments

    NASA Astrophysics Data System (ADS)

    Squires, A. D.; Kelly, M.; Lewis, R. A.

    2017-03-01

    We present terahertz spectroscopy and analysis of two commercially available quinacridone pigments in the 0.5-4.5 THz range. Our results show a clear distinction between quinacridone red and magenta pigments. We reveal four definite absorptions in the terahertz regime common to both pigments, but offset between the pigments by ˜0.2 THz. The lowest-energy line in each pigment is observed to increase in frequency by ˜0.1 THz as the temperature is reduced from 300 to 12 K.

  6. Role of thiol compounds in mammalian melanin pigmentation: Part I. Reduced and oxidized glutathione.

    PubMed

    Benedetto, J P; Ortonne, J P; Voulot, C; Khatchadourian, C; Prota, G; Thivolet, J

    1981-11-01

    Evidence for the postulated role of glutathione reductase in melanin pigmentation has been obtained by determinations of the glutathione concentrations in Tortoiseshell guinea pig skin of different colors (black, yellow, red, and white). As expected, the lowest levels of reduced glutathione (GSH) were found associated with eumelanin type pigmentation, whereas the highest ones were found in the skin with phaeomelanin producing melanocytes. On the other hand, white skin of guinea pig having no active melanocytes showed GSH levels which were intermediate between those of the black and yellow areas. These results are consistent with the view that the activity of the enzyme glutathione reductase, though not primarily related to pigmentation, plays an important role in the regulation and control of the biosynthetic activity of melanocytes leading to various types of melanin pigments.

  7. Mutations in CTNNA1 cause butterfly-shaped pigment dystrophy and perturbed retinal pigment epithelium integrity

    PubMed Central

    Saksens, Nicole T.M.; Krebs, Mark P.; Schoenmaker-Koller, Frederieke E.; Hicks, Wanda; Yu, Minzhong; Shi, Lanying; Rowe, Lucy; Collin, Gayle B.; Charette, Jeremy R.; Letteboer, Stef J.; Neveling, Kornelia; van Moorsel, Tamara W.; Abu-Ltaif, Sleiman; De Baere, Elfride; Walraedt, Sophie; Banfi, Sandro; Simonelli, Francesca; Cremers, Frans P.M.; Boon, Camiel J.F.; Roepman, Ronald; Leroy, Bart P.; Peachey, Neal S.; Hoyng, Carel B.; Nishina, Patsy M.; den Hollander, Anneke I.

    2015-01-01

    Butterfly-shaped pigment dystrophy is an eye disease characterized by lesions in the macula that can resemble the wings of a butterfly. Here, we report the identification of heterozygous missense mutations in the α-catenin 1 (CTNNA1) gene in three families with butterfly-shaped pigment dystrophy. In addition, we identified a Ctnna1 missense mutation in a chemically induced mouse mutant, tvrm5. Parallel clinical phenotypes were observed in the retinal pigment epithelium (RPE) of individuals with butterfly-shaped pigment dystrophy and in tvrm5 mice, including pigmentary abnormalities, focal thickening and elevated lesions, and decreased light-activated responses. Morphological studies in tvrm5 mice revealed increased cell shedding and large multinucleated RPE cells, suggesting defects in intercellular adhesion and cytokinesis. This study identifies CTNNA1 gene variants as a cause of macular dystrophy, suggests that CTNNA1 is involved in maintaining RPE integrity, and suggests that other components that participate in intercellular adhesion may be implicated in macular disease. PMID:26691986

  8. Effect of wavelength on cutaneous pigment using pulsed irradiation

    SciTech Connect

    Sherwood, K.A.; Murray, S.; Kurban, A.K.; Tan, O.T.

    1989-05-01

    Several reports have been published over the last two decades describing the successful removal of benign cutaneous pigmented lesions such as lentigines, cafe au lait macules' nevi, nevus of Ota, and lentigo maligna by a variety of lasers such as the excimer (351 nm), argon (488,514 nm), ruby (694 nm), Nd:YAG (1060 nm), and CO/sub 2/ (10,600 nm). Laser treatment has been applied to lesions with a range of pigment depths from superficial lentigines in the epidermis to the nevus of Ota in the reticular dermis. Widely divergent laser parameters of wavelength, pulse duration, energy density, and spotsizes have been used, but the laser parameters used to treat this range of lesions have been arbitrary, with little effort focused on defining optimal laser parameters for removal of each type. In this study, miniature black pig skin was exposed to five wavelengths (504, 590, 694, 720, and 750 nm) covering the absorption spectrum of melanin. At each wavelength, a range of energy densities was examined. Skin biopsies taken from laser-exposed sites were examined histologically in an attempt to establish whether optimal laser parameters exist for destroying pigment cells in skin. Of the five wavelengths examined, 504 nm produced the most pigment specific injury; this specificity being maintained even at the highest energy density of 7.0 J/cm2. Thus, for the destruction of melanin-containing cells in the epidermal compartment, 504 nm wavelength appears optimal.

  9. Endocrine-disrupting chemicals and skin manifestations.

    PubMed

    Ju, Qiang; Zouboulis, Christos C

    2016-09-01

    Endocrine-disrupting chemicals (EDCs) are exogenous compounds that have the ability to disrupt the production and actions of hormones through direct or indirect interaction with hormone receptors, thus acting as agonists or antagonists. Human health is affected after either individual occupation or dietary and environmental exposure to EDCs. On the other hand, skin is one of the largest organs of the body and its main function is protection from noxious substances. EDCs perturb the endocrine system, and they are also carcinogenic, immunotoxic, and hepatotoxic to human skin. In addition, their effects on keratinocytes, melanocytes, sebocytes, inflammatory and immunological cells, and skin stem cells produce inflammatory and allergic skin diseases, chloracne, disorders of skin pigmentation, skin cancer, and skin aging. Mechanisms, which EDCs use to induce these skin disorders are complicated, and involve the interference of endogenous hormones and most importantly the activation of the aryl hydrocarbon receptor signal pathway. Further studies on EDCs and skin diseases are necessary to elucidate these mechanisms.

  10. Skin Hyperpigmentation in Indian Population: Insights and Best Practice

    PubMed Central

    Nouveau, Stephanie; Agrawal, Divya; Kohli, Malavika; Bernerd, Francoise; Misra, Namita; Nayak, Chitra Shivanand

    2016-01-01

    Skin pigmentation is one of the most strikingly variable phenotypes in humans, therefore making cutaneous pigmentation disorders frequent symptoms manifesting in a multitude of forms. The most common among them include lentigines, postinflammatory hyperpigmentation, dark eye circles, and melasma. Variability of skin tones throughout the world is well-documented, some skin tones being reported as more susceptible to pigmentation disorders than others, especially in Asia and India. Furthermore, exposure to ultraviolet radiation is known to trigger or exacerbate pigmentation disorders. Preventive strategies for photoprotection and treatment modalities including topical and other medical approaches have been adopted by dermatologists to mitigate these disorders. This review article outlines the current knowledge on pigmentation disorders including pathophysiology, molecular profiling, and therapeutic options with a special focus on the Indian population. PMID:27688436

  11. Effects of ultraviolet radiation, visible light, and infrared radiation on erythema and pigmentation: a review.

    PubMed

    Sklar, Lindsay R; Almutawa, Fahad; Lim, Henry W; Hamzavi, Iltefat

    2013-01-01

    The effects of ultraviolet radiation, visible light, and infrared radiation on cutaneous erythema, immediate pigment darkening, persistent pigment darkening, and delayed tanning are affected by a variety of factors. Some of these factors include the depth of cutaneous penetration of the specific wavelength, the individual skin type, and the absorption spectra of the different chromophores in the skin. UVB is an effective spectrum to induce erythema, which is followed by delayed tanning. UVA induces immediate pigment darkening, persistent pigment darkening, and delayed tanning. At high doses, UVA (primarily UVA2) can also induce erythema in individuals with skin types I-II. Visible light has been shown to induce erythema and a tanning response in dark skin, but not in fair skinned individuals. Infrared radiation produces erythema, which is probably a thermal effect. In this article we reviewed the available literature on the effects of ultraviolet radiation, visible light, and infrared radiation on the skin in regards to erythema and pigmentation. Much remains to be learned on the cutaneous effects of visible light and infrared radiation.

  12. Two light-activated neuroendocrine circuits arising in the eye trigger physiological and morphological pigmentation.

    PubMed

    Bertolesi, Gabriel E; Hehr, Carrie L; Munn, Hayden; McFarlane, Sarah

    2016-11-01

    Two biological processes regulate light-induced skin colour change. A fast 'physiological pigmentation change' (i.e. circadian variations or camouflage) involves alterations in the distribution of pigment containing granules in the cytoplasm of chromatophores, while a slower 'morphological pigmentation change' (i.e. seasonal variations) entails changes in the number of pigment cells or pigment type. Although linked processes, the neuroendocrine coordination triggering each response remains largely obscure. By evaluating both events in Xenopus laevis embryos, we show that morphological pigmentation initiates by inhibiting the activity of the classical retinal ganglion cells. Morphological pigmentation is always accompanied by physiological pigmentation, and a melatonin receptor antagonist prevents both responses. Physiological pigmentation also initiates in the eye, but with repression of melanopsin-expressing retinal ganglion cell activity that leads to secretion of alpha-melanocyte-stimulating hormone (α-MSH). Our findings suggest a model in which eye photoperception links physiological and morphological pigmentation by altering α-MSH and melatonin production, respectively.

  13. Objective determination of Fitzpatrick skin type.

    PubMed

    Ravnbak, Mette Henriksen

    2010-08-01

    The overall aim of this Ph.D. project was to clarify what the subjective Fitzpatrick skin type represents with regard to the skin's reaction to UVR. Fitzpatrick skin type is used as an expression of the constitutive UV-sensitivity. It has been used for guiding dose-levels in phototherapy and is an important risk factor for skin cancer. The subjective Fitzpatrick skin type and the measured skin type PPF (pigment protection factor, calculated based on a skin reflectance measurement, predicts the UV-dose (SED) to give 1 MED) were investigated parallelly in relation to the clinically determined dose to erythema (MED) and/or pigmentation (MMD) to determine which one related best. PPF is an established method for assessing UV-sensitivity by predicting SED to MED. UV-dose to MED and/or MMD was determined after single UV-exposure to Solar Simulator on nates (n= 84) and after single and multiple (5, 6 or 12) UV-exposures (n = 24-62) on the back to four UV-sources (nUVB, Solar, bUVA and UVA1). SED to MMD was also related to wavelength. MED was only determined after a single and four UV-exposures to narrowband UVB (nUVB) and Solar Simulator (Solar). Volunteers with a broad range of constitutive pigmentation (skin types I-V) were included. Equal MMD doses (predetermined after a single UV-exposure) were used at the multiple exposures. The absolute increase in pigmentation after 6 and 12 UV-exposures, where steady-state pigmentation was reached, was independent of skin type and therefore could not enter into the calculations. But it proved that the MMD determinations after single exposure were correct and could be used at multiple UV-exposures. In contrary to what we expected, our results indicate that people may refer to the constitutive pigmentation, when they reply to the question of Fitzpatrick skin type. This applied to both erythema and pigmentation response as both dose to MED and MMD showed a better correlation to nates than to the back. As expected, our results from the

  14. Connexins and pannexins in the integumentary system: the skin and appendages.

    PubMed

    Faniku, Chrysovalantou; Wright, Catherine S; Martin, Patricia E

    2015-08-01

    The integumentary system comprises the skin and its appendages, which includes hair, nails, feathers, sebaceous and eccrine glands. In this review, we focus on the expression profile of connexins and pannexins throughout the integumentary system in mammals, birds and fish. We provide a picture of the complexity of the connexin/pannexin network illustrating functional importance of these proteins in maintaining the integrity of the epidermal barrier. The differential regulation and expression of connexins and pannexins during skin renewal, together with a number of epidermal, hair and nail abnormalities associated with mutations in connexins, emphasize that the correct balance of connexin and pannexin expression is critical for maintenance of the skin and its appendages with both channel and non-channel functions playing profound roles. Changes in connexin expression during both hair and feather regeneration provide suggestions of specialized communication compartments. Finally, we discuss the potential use of zebrafish as a model for connexin skin biology, where evidence mounts that differential connexin expression is involved in skin patterning and pigmentation.

  15. Color stability of thermochromic pigment in maxillofacial silicone

    PubMed Central

    Lassila, Lippo V.J.; Tolvanen, Mimmi; Valittu, Pekka K.

    2013-01-01

    PURPOSE Maxillofacial silicone elastomer is usually colored intrinsically with color pigments to match skin colors. The purpose of this study was to investigate the color stability of a maxillofacial silicone elastomer, colored with a thermochromic, color changing pigment. MATERIALS AND METHODS Disc-shaped maxillofacial silicone specimens were prepared and divided into 3 groups: a conventionally colored control group, one group additionally colored with 0.2 wt% thermochromic pigment , and one group with 0.6 wt% thermochromic pigment. Half of the surface of each specimen was covered with an aluminium foil. All of the specimens were exposed to UV radiation in 6 hour cycles over 46 days. In between the UV exposures, half of the specimens were stored in darkness, at room temperature, and the other half was stored in an incubator, at a humidity of 97% and a temperature of +37℃. Color measurements were made with a spectrophotometer and registered according to the CIELAB L*a*b* color model system. The changes in L*, a* and b* values during artificial aging were statistically analyzed by using paired samples t-test and repeated measures ANOVA. P-values <.05 were considered as statistically significant. RESULTS The UV exposure resulted in visually noticeable and statistically significant color changes in the L*, a* and b* values in both of the test groups containing thermochromic pigment. Storage in the incubator lead to statistically significant color changes in the a* and b* values of the specimens containing thermochromic pigment, compared to those stored at room temperature. CONCLUSION The specimens containing thermochromic pigment were very sensitive to UV radiation, and the thermochromic pigment is not suitable, as such, to be used in maxillofacial prostheses. PMID:23755330

  16. Delayed induction of pigmented spots on UVB-irradiated hairless mice.

    PubMed

    Naganumaa, M; Yagi, E; Fukuda, M

    2001-01-01

    Human skin exposed to solar radiation for a long time subsequently develops pigmented spots, which are named solar lentigines. Since no animal model of this process is currently available, we attempted to induce similar spots in pigmented hairless mice. The mice were irradiated at 38 or 94 mJ/cm(2) three times/week for various periods of time (1-8 weeks) under an ultraviolet light source (Toshiba FL-SE; UVB). Skin pigmentation of irradiated mice was visually observed and skin color was determined with a colorimeter for 78 weeks. Uniform pigmentation was induced, but persisted only during exposure, disappearing completely within 2 weeks after cessation of exposure. At about 28 weeks after the first exposure, pigmented spots suddenly began to appear. These pigmented spots were less than 2 mm in diameter and light brown in color. The length of the latent period until appearance and the extent of development of these spots were dependent on the exposure period. Histological examination revealed increased numbers of active melanocytes and melanin granules in the affected epidermis. These pigmented spots closely resemble solar lentigines in humans, and the mice should be useful as an animal model of solar lentigines.

  17. Reticulate Pigmentation Associated with Scarring Alopecia in an Elderly Woman: An Unusual Manifestation of Lichen Planus Pigmentosus

    PubMed Central

    Sharma, Vinod Kumar; Bhari, Neetu; Subhadarshani, Sweta; Taneja, Neha; Deepak, Rakesh Kumar

    2016-01-01

    A 70-year-old woman presented with generalized reticulate pigmentation, scarring alopecia, and few discrete, violaceous plaques over the trunk and forearm. Dermoscopic evaluation of the reticulate plaque showed reticulate hyperpigmentation with multiple telangiectasias, and skin biopsy showed lichenoid interface dermatitis with marked pigment incontinence. Thus, a final diagnosis of poikiloderma due to lichen planus pigmentosus was considered. PMID:27904206

  18. Reticulate Pigmentation Associated with Scarring Alopecia in an Elderly Woman: An Unusual Manifestation of Lichen Planus Pigmentosus.

    PubMed

    Sharma, Vinod Kumar; Bhari, Neetu; Subhadarshani, Sweta; Taneja, Neha; Deepak, Rakesh Kumar

    2016-01-01

    A 70-year-old woman presented with generalized reticulate pigmentation, scarring alopecia, and few discrete, violaceous plaques over the trunk and forearm. Dermoscopic evaluation of the reticulate plaque showed reticulate hyperpigmentation with multiple telangiectasias, and skin biopsy showed lichenoid interface dermatitis with marked pigment incontinence. Thus, a final diagnosis of poikiloderma due to lichen planus pigmentosus was considered.

  19. Airborne particle exposure and extrinsic skin aging.

    PubMed

    Vierkötter, Andrea; Schikowski, Tamara; Ranft, Ulrich; Sugiri, Dorothea; Matsui, Mary; Krämer, Ursula; Krutmann, Jean

    2010-12-01

    For decades, extrinsic skin aging has been known to result from chronic exposure to solar radiation and, more recently, to tobacco smoke. In this study, we have assessed the influence of air pollution on skin aging in 400 Caucasian women aged 70-80 years. Skin aging was clinically assessed by means of SCINEXA (score of intrinsic and extrinsic skin aging), a validated skin aging score. Traffic-related exposure at the place of residence was determined by traffic particle emissions and by estimation of soot in fine dust. Exposure to background particle concentration was determined by measurements of ambient particles at fixed monitoring sites. The impact of air pollution on skin aging was analyzed by linear and logistic regression and adjusted for potential confounding variables. Air pollution exposure was significantly correlated to extrinsic skin aging signs, in particular to pigment spots and less pronounced to wrinkles. An increase in soot (per 0.5 × 10(-5) per m) and particles from traffic (per 475  kg per year and square km) was associated with 20% more pigment spots on forehead and cheeks. Background particle pollution, which was measured in low residential areas of the cities without busy traffic and therefore is not directly attributable to traffic but rather to other sources of particles, was also positively correlated to pigment spots on face. These results indicate that particle pollution might influence skin aging as well.

  20. Raman Spectroscopy of Microbial Pigments

    PubMed Central

    Edwards, Howell G. M.; Oren, Aharon

    2014-01-01

    Raman spectroscopy is a rapid nondestructive technique providing spectroscopic and structural information on both organic and inorganic molecular compounds. Extensive applications for the method in the characterization of pigments have been found. Due to the high sensitivity of Raman spectroscopy for the detection of chlorophylls, carotenoids, scytonemin, and a range of other pigments found in the microbial world, it is an excellent technique to monitor the presence of such pigments, both in pure cultures and in environmental samples. Miniaturized portable handheld instruments are available; these instruments can be used to detect pigments in microbiological samples of different types and origins under field conditions. PMID:24682303

  1. Role of antioxidants in the skin: anti-aging effects.

    PubMed

    Masaki, Hitoshi

    2010-05-01

    Intracellular and extracellular oxidative stress initiated by reactive oxygen species (ROS) advance skin aging, which is characterized by wrinkles and atypical pigmentation. Because UV enhances ROS generation in cells, skin aging is usually discussed in relation to UV exposure. The use of antioxidants is an effective approach to prevent symptoms related to photo-induced aging of the skin. In this review, the mechanisms of ROS generation and ROS elimination in the body are summarized. The effects of ROS generated in the skin and the roles of ROS in altering the skin are also discussed. In addition, the effects of representative antioxidants on the skin are summarized with a focus on skin aging.

  2. The Protective Role of Melanin Against UV Damage in Human Skin

    PubMed Central

    Brenner, Michaela; Hearing, Vincent J.

    2009-01-01

    Human skin is repeatedly exposed to ultraviolet radiation (UVR) that influences the function and survival of many cell types and is regarded as the main causative factor in the induction of skin cancer. It has been traditionally believed that skin pigmentation is the most important photoprotective factor, since melanin, besides functioning as a broadband UV absorbent, has antioxidant and radical scavenging properties. Besides, many epidemiological studies have shown a lower incidence for skin cancer in individuals with darker skin compared to those with fair skin. Skin pigmentation is of great cultural and cosmetic importance, yet the role of melanin in photoprotection is still controversial. This article outlines the major acute and chronic effects of UV radiation on human skin, the properties of melanin, the regulation of pigmentation and its effect on skin cancer prevention. PMID:18435612

  3. Dermoscopy of Pigmented Bowen's Disease Mimicking Early Superficial Spreading Melanoma

    PubMed Central

    Hayashi, Yuka; Tanaka, Masaru; Suzaki, Reiko; Mori, Nuiko; Konohana, Izumi

    2009-01-01

    A 89-year-old Japanese woman presented at our clinic because of a several months’ history of an asymptomatic gradually enlarging pigmented skin lesion on the dorsum of the left foot. Physical examination revealed a single hyperpigmented oval macule of 5 mm with a rough surface. The color of the lesion was dark brown to light brown. Dermoscopic examination demonstrated atypical pigment network with small dotted vessels. Irregular streaks were also partially noted at the periphery. We suspected superficial spreading melanoma and performed an excision. The histologic features were consistent with a diagnosis of pigmented Bowen's disease. We could not completely account for dermoscopic aspects from the pathological findings of hematoxylin and eosin-stained specimens; therefore, specimens were stained with Fontana-Masson stain. It clearly demonstrated the distribution of melanin in the epidermis. We concluded that atypical network was due to an uneven melanin deposition in the variably thickened epidermal rete ridges. PMID:20652107

  4. Skin Conditions

    MedlinePlus

    Your skin is your body's largest organ. It covers and protects your body. Your skin Holds body fluids in, preventing dehydration Keeps harmful ... it Anything that irritates, clogs, or inflames your skin can cause symptoms such as redness, swelling, burning, ...

  5. Aging Skin

    MedlinePlus

    ... email address Submit Home > Healthy Aging > Wellness Healthy Aging Aging skin More information on aging skin When it ... treated early. Return to top More information on Aging skin Read more from womenshealth.gov Varicose Veins ...

  6. Snapshot RGB mapping of skin melanin and hemoglobin

    NASA Astrophysics Data System (ADS)

    Spigulis, Janis; Oshina, Ilze

    2015-05-01

    The concept of snapshot red-green-blue (RGB) multispectral imaging was applied for skin chromophore mapping. Three monochromatic spectral images have been extracted from a single RGB image dataset at simultaneous illumination of skin by 473-, 532-, and 659-nm laser lines. The spectral images were further transformed into distribution maps of skin melanin, oxyhemoglobin, and deoxyhemoglobin, related to pigmented and vascular skin malformations. The performance and clinical potential of the proposed technique are discussed.

  7. Skin abscess

    MedlinePlus

    Abscess - skin; Cutaneous abscess; Subcutaneous abscess; MRSA - abscess; Staph infection - abscess ... Skin abscesses are common and affect people of all ages. They occur when an infection causes pus ...

  8. Melanin: the biophysiology of oral melanocytes and physiological oral pigmentation.

    PubMed

    Feller, Liviu; Masilana, Aubrey; Khammissa, Razia A G; Altini, Mario; Jadwat, Yusuf; Lemmer, Johan

    2014-03-24

    The presence of melanocytes in the oral epithelium is a well-established fact, but their physiological functions are not well defined. Melanin provides protection from environmental stressors such as ultraviolet radiation and reactive oxygen species; and melanocytes function as stress-sensors having the capacity both to react to and to produce a variety of microenvironmental cytokines and growth factors, modulating immune, inflammatory and antibacterial responses. Melanocytes also act as neuroendocrine cells producing local neurotransmitters including acetylcholine, catecholamines and opioids, and hormones of the melanocortin system such as proopiomelanocortin, adrenocorticotropic hormone and α-melanocyte stimulating hormone, that participate in intracellular and in intercellular signalling pathways, thus contributing to tissue homeostasis.There is a wide range of normal variation in melanin pigmentation of the oral mucosa. In general, darker skinned persons more frequently have oral melanin pigmentation than light-skinned persons. Variations in oral physiological pigmentation are genetically determined unless associated with some underlying disease.In this article, we discuss some aspects of the biophysiology of oral melanocytes, of the functions of melanin, and of physiological oral pigmentation.

  9. The Role of the Skin Barrier in Occupational Skin Diseases.

    PubMed

    Kasemsarn, Pranee; Bosco, Joanna; Nixon, Rosemary L

    2016-01-01

    Occupational skin diseases (OSDs) are the second most common occupational diseases worldwide. Occupational contact dermatitis (OCD) is the most frequent OSD, and comprises irritant contact dermatitis (ICD), allergic contact dermatitis (ACD), contact urticaria and protein contact dermatitis. There are many endogenous and exogenous factors which affect the development of OCD, including age, sex, ethnicity, atopic skin diathesis, certain occupations and environmental factors. One of the most important contributing causes is skin barrier dysfunction. The skin provides a first-line defense from environmental assaults and incorporates physical, chemical and biological protection. Skin barrier disturbance plays a crucial role in various skin diseases such as atopic dermatitis (AD), ichthyosis, ICD and ACD. Genetic factors, such as filaggrin gene (FLG) mutations, and external factors, such as skin irritants interfering with stratum corneum structure and composition, may lead to abnormalities in skin barrier function and increased vulnerability to skin diseases. FLG encodes the cornified envelope protein, filaggrin, which is involved in skin barrier function. FLG mutation is associated with the development of OCD. High-risk occupations for OCD include health care workers, hairdressers and construction workers. There are often multiple contributing causes to OCD, as workers are exposed to both irritants and allergens. AD is also associated with skin barrier disruption and plays an important role in OCD. ICD often precedes and facilitates the development of ACD, with impairment of the skin barrier contributing to the concurrence of ICD and ACD in many workers with OCD.

  10. Nonphotosynthetic Pigments as Potential Biosignatures

    PubMed Central

    Cockell, Charles S.; Meadows, Victoria S.

    2015-01-01

    Abstract Previous work on possible surface reflectance biosignatures for Earth-like planets has typically focused on analogues to spectral features produced by photosynthetic organisms on Earth, such as the vegetation red edge. Although oxygenic photosynthesis, facilitated by pigments evolved to capture photons, is the dominant metabolism on our planet, pigmentation has evolved for multiple purposes to adapt organisms to their environment. We present an interdisciplinary study of the diversity and detectability of nonphotosynthetic pigments as biosignatures, which includes a description of environments that host nonphotosynthetic biologically pigmented surfaces, and a lab-based experimental analysis of the spectral and broadband color diversity of pigmented organisms on Earth. We test the utility of broadband color to distinguish between Earth-like planets with significant coverage of nonphotosynthetic pigments and those with photosynthetic or nonbiological surfaces, using both 1-D and 3-D spectral models. We demonstrate that, given sufficient surface coverage, nonphotosynthetic pigments could significantly impact the disk-averaged spectrum of a planet. However, we find that due to the possible diversity of organisms and environments, and the confounding effects of the atmosphere and clouds, determination of substantial coverage by biologically produced pigments would be difficult with broadband colors alone and would likely require spectrally resolved data. Key Words: Biosignatures—Exoplanets—Halophiles—Pigmentation—Reflectance spectroscopy—Spectral models. Astrobiology 15, 341–361. PMID:25941875

  11. Energy Conserving Coating - Pigment Research

    DTIC Science & Technology

    1991-05-01

    indicated above, changes from yellow to orange. Thermochromic CVL Mixtures Thermochromic dye mixtures were made by reacting specific leuco (colorless...2 Photochromic Pigments and Dyes ................................. 3 Thermochromic Inorganic Pigments...describing the state of the art in color changing materials, from liquid crystals to thermochromic metal complexes to photochromic spiran dyes . The re- search

  12. Nonphotosynthetic pigments as potential biosignatures.

    PubMed

    Schwieterman, Edward W; Cockell, Charles S; Meadows, Victoria S

    2015-05-01

    Previous work on possible surface reflectance biosignatures for Earth-like planets has typically focused on analogues to spectral features produced by photosynthetic organisms on Earth, such as the vegetation red edge. Although oxygenic photosynthesis, facilitated by pigments evolved to capture photons, is the dominant metabolism on our planet, pigmentation has evolved for multiple purposes to adapt organisms to their environment. We present an interdisciplinary study of the diversity and detectability of nonphotosynthetic pigments as biosignatures, which includes a description of environments that host nonphotosynthetic biologically pigmented surfaces, and a lab-based experimental analysis of the spectral and broadband color diversity of pigmented organisms on Earth. We test the utility of broadband color to distinguish between Earth-like planets with significant coverage of nonphotosynthetic pigments and those with photosynthetic or nonbiological surfaces, using both 1-D and 3-D spectral models. We demonstrate that, given sufficient surface coverage, nonphotosynthetic pigments could significantly impact the disk-averaged spectrum of a planet. However, we find that due to the possible diversity of organisms and environments, and the confounding effects of the atmosphere and clouds, determination of substantial coverage by biologically produced pigments would be difficult with broadband colors alone and would likely require spectrally resolved data.

  13. Nonphotosynthetic Pigments as Potential Biosignatures

    NASA Astrophysics Data System (ADS)

    Schwieterman, Edward W.; Cockell, Charles S.; Meadows, Victoria S.

    2015-05-01

    Previous work on possible surface reflectance biosignatures for Earth-like planets has typically focused on analogues to spectral features produced by photosynthetic organisms on Earth, such as the vegetation red edge. Although oxygenic photosynthesis, facilitated by pigments evolved to capture photons, is the dominant metabolism on our planet, pigmentation has evolved for multiple purposes to adapt organisms to their environment. We present an interdisciplinary study of the diversity and detectability of nonphotosynthetic pigments as biosignatures, which includes a description of environments that host nonphotosynthetic biologically pigmented surfaces, and a lab-based experimental analysis of the spectral and broadband color diversity of pigmented organisms on Earth. We test the utility of broadband color to distinguish between Earth-like planets with significant coverage of nonphotosynthetic pigments and those with photosynthetic or nonbiological surfaces, using both 1-D and 3-D spectral models. We demonstrate that, given sufficient surface coverage, nonphotosynthetic pigments could significantly impact the disk-averaged spectrum of a planet. However, we find that due to the possible diversity of organisms and environments, and the confounding effects of the atmosphere and clouds, determination of substantial coverage by biologically produced pigments would be difficult with broadband colors alone and would likely require spectrally resolved data.

  14. Comparative chromatography of chloroplast pigment

    NASA Technical Reports Server (NTRS)

    Grandolfo, M.; Sherma, J.; Strain, H. H.

    1969-01-01

    Methods for isolation of low concentration pigments of the cocklebur species are described. The methods entail two step chromatography so that the different sorption properties of the various pigments in varying column parameters can be utilized. Columnar and thin layer methods are compared. Many conditions influence separability of the chloroplasts.

  15. New directions in phthalocyanine pigments

    NASA Technical Reports Server (NTRS)

    Trinh, Diep VO

    1994-01-01

    Phthalocyanines have been used as a pigment in coatings and related applications for many years. These pigments are some of the most stable organic pigments known. The phthalo blue and green pigments have been known to be ultraviolet (UV) stable and thermally stable to over 400 C. These phthalocyanines are both a semiconductor and photoconductor, exhibiting catalytic activity and photostabilization capability of polymers. Many metal free and metallic phthalocyanine derivatives have been prepared. Development of the new classes of phthalocyanine pigment could be used as coating on NASA spacecraft material such as glass to decrease the optical degradation from UV light, the outside of the space station modules for UV protection, and coating on solar cells to increase lifetime and efficiency.

  16. Two newly identified genetic determinants of pigmentation in Europeans.

    PubMed

    Sulem, Patrick; Gudbjartsson, Daniel F; Stacey, Simon N; Helgason, Agnar; Rafnar, Thorunn; Jakobsdottir, Margret; Steinberg, Stacy; Gudjonsson, Sigurjon A; Palsson, Arnar; Thorleifsson, Gudmar; Pálsson, Snaebjörn; Sigurgeirsson, Bardur; Thorisdottir, Kristin; Ragnarsson, Rafn; Benediktsdottir, Kristrun R; Aben, Katja K; Vermeulen, Sita H; Goldstein, Alisa M; Tucker, Margaret A; Kiemeney, Lambertus A; Olafsson, Jon H; Gulcher, Jeffrey; Kong, Augustine; Thorsteinsdottir, Unnur; Stefansson, Kari

    2008-07-01

    We present results from a genome-wide association study for variants associated with human pigmentation characteristics among 5,130 Icelanders, with follow-up analyses in 2,116 Icelanders and 1,214 Dutch individuals. Two coding variants in TPCN2 are associated with hair color, and a variant at the ASIP locus shows strong association with skin sensitivity to sun, freckling and red hair, phenotypic characteristics similar to those affected by well-known mutations in MC1R.

  17. Retinal abnormalities in β-thalassemia major

    PubMed Central

    Bhoiwala, Devang L.; Dunaief, Joshua L.

    2015-01-01

    Patients with beta (β)-thalassemia (β-TM: thalassemia major, β-TI: thalassemia intermedia) have a variety of complications that may affect all organs, including the eye. Ocular abnormalities include retinal pigment epithelium degeneration, angioid streaks, venous tortuosity, night blindness, visual field defects, decreased visual acuity, color vision abnormalities, and acute visual loss. Patients with β-TM are transfusion dependent and require iron chelation therapy (ICT) in order to survive. Retinal degeneration may result from either retinal iron accumulation from transfusion-induced iron overload or retinal toxicity induced by ICT. Some who were never treated with ICT exhibited retinopathy, and others receiving ICT had chelator-induced retinopathy. We will focus on retinal abnormalities present in individuals with β-TM viewed in light of new findings on the mechanisms and manifestations of retinal iron toxicity. PMID:26325202

  18. Idiopathic eruptive macular pigmentation with papillomatosis: Report of nine cases.

    PubMed

    Joshi, Rajiv

    2007-01-01

    Nine patients, seven males and two females aged 6-14 years, presented with extensive, asymptomatic, brown-black macules and mildly elevated, pigmented lesions of a few months' duration. The sites affected were the face, trunk and proximal extremities. The skin lesions were discrete and individual lesions were less than 2 cm in size. The clinical diagnoses rendered by the referring physicians were lichen planus pigmentosus, urticaria pigmentosa, erythema dyschromicum perstans and postinflammatory hyperpigmentation. Histology in all nine cases showed papillomatosis of the dermis with prominent pigmentation of the basal layer (pigmented papillomatosis) without any significant dermal inflammation. Two cases had spores of Pityrosporum ovale in the thickened horny layer, one of which also had, in addition, bacterial colonies in the stratum corneum. The pigmentation resolved on its own over several months. This presentation is similar to the previously described idiopathic eruptive macular pigmentation with the additional histological finding of papillomatosis that is being described for the first time and may be nosologically related to acanthosis nigricans and confluent and reticulate papillomatosis.

  19. Pigmented lesions of the nail unit: clinical and histopathologic features.

    PubMed

    Ruben, Beth S

    2010-09-01

    Probably the most common reason to perform biopsy of the nail unit is for the evaluation of irregular pigmentation, especially longitudinal melanonychia or pigmented bands. When narrow and solitary, these are usually the product of melanocytic activation/hypermelanosis, lentigines, or melanocytic nevi. Multiple pigmented bands are generally a benign finding, the result of melanocytic activation, as seen in racial pigmentation in darker-skinned patients, for example. In the context of an irregular, broad, heterogeneous or "streaky" band, the chief concern is the exclusion of subungual melanoma. Before assessing the histologic features of any such entities, it is important to understand the normal nail anatomy and melanocytic density of nail unit epithelium, as well as the type of specimen submitted, and whether it is adequate to undertake a proper histologic evaluation. The criteria for diagnosis and prognosis of melanoma of the nail unit are still evolving, and a variety of factors must be weighed in the balance to make a correct diagnosis. The importance of the clinical context cannot be overemphasized. There are also nonmelanocytic conditions to be considered that may produce worrisome nail discoloration, such as subungual hemorrhage, squamous cell carcinoma, and pigmented onychomycosis.

  20. Changes in chloroplast pigments of olive varieties during fruit ripening.

    PubMed

    Roca, M; Mínguez-Mosquera, M I

    2001-02-01

    Changes in chlorophyll and carotenoid pigments of five olive (Olea europaea L.) varieties destined for milling were investigated at six consecutive ripening stages. There was a manifest dependence between olive variety, moment of picking, and chloroplast pigment composition of the fruits. Although the content of chlorophylls and carotenoids differed with fruit variety, ripening always involved their gradual loss, which becames more pronounced with increased presence of anthocyanin compounds. The relative rates of disappearance of chlorophylls and carotenoids were markedly different between varieties, implying that the catabolism of these pigments takes place at a relative rate inherent to each variety. The varieties less rich in pigments showed the most extreme behavior. The highest relative rate of disappearance was observed in fruits of the Blanqueta variety, and the lowest was observed in those of Arbequina. The chlorophyll a/chlorophyll b ratio remained practically constant during ripening, with a value very similar for Hojiblanca, Picual, Cornicabra, and Blanqueta, but much higher for Arbequina, implying that the structure of the photosynthetic apparatus is different in the latter variety. In the five varieties studied, lutein was the slowest carotenoid to be degraded, so that its percentage in the fruits increased with ripening, whereas beta-carotene was the fastest to disappear. In ripe fruits covered with anthocyanins, chloroplast pigments were retained in both skin and pulp, with the rate of disappearance being much higher in the latter.

  1. The ocular albinism type 1 protein, an intracellular G protein-coupled receptor, regulates melanosome transport in pigment cells.

    PubMed

    Palmisano, Ilaria; Bagnato, Paola; Palmigiano, Angela; Innamorati, Giulio; Rotondo, Giuseppe; Altimare, Domenico; Venturi, Consuelo; Sviderskaya, Elena V; Piccirillo, Rosanna; Coppola, Massimiliano; Marigo, Valeria; Incerti, Barbara; Ballabio, Andrea; Surace, Enrico M; Tacchetti, Carlo; Bennett, Dorothy C; Schiaffino, Maria Vittoria

    2008-11-15

    The protein product of the ocular albinism type 1 gene, named OA1, is a pigment cell-specific G protein-coupled receptor exclusively localized to intracellular organelles, namely lysosomes and melanosomes. Loss of OA1 function leads to the formation of macromelanosomes, suggesting that this receptor is implicated in organelle biogenesis, however the mechanism involved in the pathogenesis of the disease remains obscure. We report here the identification of an unexpected abnormality in melanosome distribution both in retinal pigment epithelium (RPE) and skin melanocytes of Oa1-knock-out (KO) mice, consisting in a displacement of the organelles from the central cytoplasm towards the cell periphery. Despite their depletion from the microtubule (MT)-enriched perinuclear region, Oa1-KO melanosomes were able to aggregate at the centrosome upon disruption of the actin cytoskeleton or expression of a dominant-negative construct of myosin Va. Consistently, quantification of organelle transport in living cells revealed that Oa1-KO melanosomes displayed a severe reduction in MT-based motility; however, this defect was rescued to normal following inhibition of actin-dependent capture at the cell periphery. Together, these data point to a defective regulation of organelle transport in the absence of OA1 and imply that the cytoskeleton might represent a downstream effector of this receptor. Furthermore, our results enlighten a novel function for OA1 in pigment cells and suggest that ocular albinism type 1 might result from a different pathogenetic mechanism than previously thought, based on an organelle-autonomous signalling pathway implicated in the regulation of both membrane traffic and transport.

  2. Iris phenotypes and pigment dispersion caused by genes influencing pigmentation.

    PubMed

    Anderson, Michael G; Hawes, Norman L; Trantow, Colleen M; Chang, Bo; John, Simon W M

    2008-10-01

    Spontaneous mutations altering mouse coat colors have been a classic resource for discovery of numerous molecular pathways. Although often overlooked, the mouse iris is also densely pigmented and easily observed, thus representing a similarly powerful opportunity for studying pigment cell biology. Here, we present an analysis of iris phenotypes among 16 mouse strains with mutations influencing melanosomes. Many of these strains exhibit biologically and medically relevant phenotypes, including pigment dispersion, a common feature of several human ocular diseases. Pigment dispersion was identified in several strains with mutant alleles known to influence melanosomes, including beige, light, and vitiligo. Pigment dispersion was also detected in the recently arising spontaneous coat color variant, nm2798. We have identified the nm2798 mutation as a missense mutation in the Dct gene, an identical re-occurrence of the slaty light mutation. These results suggest that dysregulated events of melanosomes can be potent contributors to the pigment dispersion phenotype. Combined, these findings illustrate the utility of studying iris phenotypes as a means of discovering new pathways, and re-linking old ones, to processes of pigmented cells in health and disease.

  3. Sensitive skin: an overview.

    PubMed

    Berardesca, E; Farage, M; Maibach, H

    2013-02-01

    Sensitive skin is a condition of subjective cutaneous hyper-reactivity to environmental factors. Subjects experiencing this condition report exaggerated reactions when their skin is in contact with cosmetics, soaps and sun screens, and they often report worsening after exposure to dry and cold climate. Although no sign of irritation is commonly detected, itching, burning, stinging and a tight sensation are constantly present. Generally substances that are not commonly considered irritants are involved in this abnormal response.Sensitive skin and subjective irritation are widespread but still far from being completely defined and understood. A correlation between sensitive skin and constitutional anomalies and/or other triggering factors such as occupational skin diseases or chronic exposure to irritants has been hypothesized. Recent findings suggest that higher sensitivity can be due to different mechanisms. Hyper-reactors may have a thinner stratum corneum with a reduced corneocyte area causing a higher transcutaneous penetration of water-soluble chemicals. Alterations in vanilloid receptors and changes in neuronal transmission have been described. Monitoring skin parameters such as barrier function, proclivity to irritation, corneocyte size and sensorial transmission can also be useful to identify regional differences in skin sensitivity.

  4. [INHERITANCE OF EPIDERMIS PIGMENTATION IN SUNFLOWER ACHENES].

    PubMed

    Gorohivets, N A; Vedmedeva, E V

    2016-01-01

    Inheritance of epidermis pigmentation in the pericarp of sunflower seeds was studied. Inheritance of pigmentation was confirmed by three alleles Ew (epidermis devoid of pigmentation), Estr (epidermal pigmentation in strips), Edg (solid pigmentation). Dominance of the lack of epidermis pigmentation over striped epidermis and striped epidermis over solid pigmentation was established. It was shown that the striped epidermis pigmentation and the presence of testa layer are controlled by two genes, expression of which is independent from each other. Yellowish hypodermis was discovered in the sample I2K2218, which is inherited monogenically dominantly.

  5. Pigmented epidermal cyst with dense collection of melanin: A rare entity - Report of a case with review of the literature.

    PubMed

    Jayalakshmy, P S; Subitha, K; Priya, P V; Johnson, Gerald

    2012-05-01

    Epidermal cyst is a very common benign cystic lesion of the skin. It is usual to find ulceration of the lining epithelium, rupture of the cyst wall with chronic inflammation and foreign body giant cell reaction. But, it is very rare to see an epidermal cyst with marked accumulation of melanin pigment. Only a few cases of pigmented epidermal cyst with dense collection of melanin pigment have been published in the literature. Here, we are reporting a case of ruptured epidermal cyst with keratin granuloma formation and showing dense collection of melanin pigment.

  6. Natural pigments and sacred art

    NASA Astrophysics Data System (ADS)

    Kelekian, Lena, ,, Lady

    2010-05-01

    Since the dawn of mankind, cavemen has expressed himself through art. The earliest known cave paintings date to some 32,000 years ago and used 4 colours derived from the earth. These pigments were iron oxides and known as ochres, blacks and whites. All pigments known by the Egyptians, the Greeks, the Romans and Renaissance man were natural and it was not until the 18th century that synthetic pigments were made and widely used. Until that time all art, be it sacred or secular used only natural pigments, of which the preparation of many have been lost or rarely used because of their tedious preparation. As a geologist, a mineralogist and an artist specializing in iconography, I have been able to rediscover 89 natural pigments extracted from minerals. I use these pigments to paint my icons in the traditional Byzantine manner and also to restore old icons, bringing back their glamour and conserving them for years to come. The use of the natural pigments in its proper way also helps to preserve the traditional skills of the iconographer. In the ancient past, pigments were extremely precious. Many took an exceedingly long journey to reach the artists, and came from remote countries. Research into these pigments is the work of history, geography and anthropology. It is an interesting journey in itself to discover that the blue aquamarines came from Afghanistan, the reds from Spain, the greens Africa, and so on. In this contribution I will be describing the origins, preparation and use of some natural pigments, together with their history and provenance. Additionally, I will show how the natural pigments are used in the creation of an icon. Being a geologist iconographer, for me, is a sacrement that transforms that which is earthly, material and natural into a thing of beauty that is sacred. As bread and wine in the Eucharist, water during baptism and oil in Holy Union transmit sanctification to the beholder, natural pigments do the same when one considers an icon. The

  7. Multimodal device for assessment of skin malformations

    NASA Astrophysics Data System (ADS)

    Bekina, A.; Garancis, V.; Rubins, U.; Spigulis, J.; Valeine, L.; Berzina, A.

    2013-11-01

    A variety of multi-spectral imaging devices is commercially available and used for skin diagnostics and monitoring; however, an alternative cost-efficient device can provide an advanced spectral analysis of skin. A compact multimodal device for diagnosis of pigmented skin lesions was developed and tested. A polarized LED light source illuminates the skin surface at four different wavelengths - blue (450 nm), green (545 nm), red (660 nm) and infrared (940 nm). Spectra of reflected light from the 25 mm wide skin spot are imaged by a CMOS sensor. Four spectral images are obtained for mapping of the main skin chromophores. The specific chromophore distribution differences between different skin malformations were analyzed and information of subcutaneous structures was consecutively extracted.

  8. Skin Biomes.

    PubMed

    Fyhrquist, N; Salava, A; Auvinen, P; Lauerma, A

    2016-05-01

    The cutaneous microbiome has been investigated broadly in recent years and some traditional perspectives are beginning to change. A diverse microbiome exists on human skin and has a potential to influence pathogenic microbes and modulate the course of skin disorders, e.g. atopic dermatitis. In addition to the known dysfunctions in barrier function of the skin and immunologic disturbances, evidence is rising that frequent skin disorders, e.g. atopic dermatitis, might be connected to a dysbiosis of the microbial community and changes in the skin microbiome. As a future perspective, examining the skin microbiome could be seen as a potential new diagnostic and therapeutic target in inflammatory skin disorders.

  9. A case report of pigmented mammary Paget's disease mimicking nevus of the nipple.

    PubMed

    Tang, Xiaoyan; Umemura, Shinobu; Kumaki, Nobue; Izumi, Miki; Saito, Yuki; Suzuki, Yasuhiro; Ozawa, Akira; Tokuda, Yutaka

    2014-05-01

    A 43-year-old Japanese woman consulted our hospital for a pigmented lesion on her right nipple. Two years later, the lesion became enlarged, measuring 5 × 5 mm. It was dark brown, had an irregular shape and relatively clear borders. Incisional biopsy yielded a pathological diagnosis of junctional nevus of the skin. An additional 2 years later, a small mass developed under the right nipple area and core needle biopsy yielded a pathologic diagnosis of invasive ductal carcinoma. Partial resection of the right EC areas included the skin of the nipple and sentinel lymph node biopsy was performed. Histologically, the skin of the nipple demonstrated small clusters of pigmented carcinoma cells that were low molecular weight cytokeratin (CAM5.2) positive. Most of the carcinoma cells were small and did not have abundant cytoplasm, but nuclear enlargement and prominent nucleoli indicated malignancy, and the cytoplasm was pale compared with that of the surrounding squamous epithelial cells. Scattered dendritic melanocytes were identified by S-100 protein and HMB-45 immunohistochemically. In the upper dermis, carcinoma cells also involved the lactiferous ducts. A small focus of carcinoma cells that invaded the fat tissues did not contain melanin pigment. The final diagnosis was pigmented mammary Paget's disease. Pigmented lesions on the nipple should be carefully examined, because pigmented mammary Paget's disease sometimes mimics malignant melanoma or junctional nevus.

  10. Multispectral imaging of pigmented and vascular cutaneous malformations: the influence of laser treatment

    NASA Astrophysics Data System (ADS)

    Kuzmina, Ilona; Diebele, Ilze; Asare, Lasma; Kempele, Anna; Abelite, Anita; Jakovels, Dainis; Spigulis, Janis

    2010-11-01

    The paper investigates influence and efficacy of laser therapy on pigmented and vascular cutaneous malformations by multispectral imaging technique. Parameter mapping of skin pigmented and vascular lesions and monitoring of the laser therapy efficacy are performed by multispectral imaging in wavelength range 450-700nm by scanning step - 10nm. Parameter maps of the oxyhemoglobin deoxyhemoglobin and melanin derived from the images are presented. Possibility of laser therapy efficacy monitoring by comparison of the parameter maps before and after laser treatment has been demonstrated. As both cutaneous pigmented and vascular malformations are commonly found lesions, the parameter mapping would be a valuable method to use routinely.

  11. Characterization of the yellow pigment in the axanthic mutant of the Mexican axolotl, Ambystoma mexicanum.

    PubMed

    Bukowski, L; Erickson, K; Lyerla, T A

    1990-09-01

    The yellow pigment observed in older axanthic (ax/ax) mutant Mexican axolotls (Ambystoma mexicanum) was analyzed by thin layer chromatography and by spectrofluorometry of its acetyl derivative. Ethanol extracts from the skin of axanthic animals were acetylated and the chloroform-soluble portion of the product mixture was compared with a chloroform solution of an authentic riboflavin tetraacetate standard prepared in the same manner. The pigment in these two solutions behaved identically on thin layer chromatograms and in fluorescent emission spectroscopy. This confirms that the yellow pigment seen in these genetically axanthic animals is riboflavin and, since it cannot be synthesized by the animal, must be derived from the diet.

  12. Macular pigmentation of uncertain aetiology revisited: two case reports and a proposed algorithm for clinical classification.

    PubMed

    Chandran, Veena; Kumarasinghe, Sujith Prasad

    2017-02-01

    Ashy dermatosis, erythema dyschromicum perstans, lichen planus pigmentosus and idiopathic eruptive macular pigmentation are various types of acquired macular hyperpigmentation disorders of the skin described in literature. However, a global consensus on the definitions of these entities is lacking. We report two cases of acquired macular (hyper)pigmentation of uncertain aetiology diagnosed as ashy dermatosis and attempt to clarify the various confusing nosologies based on existing literature. We infer that acquired small and large macular pigmentation of uncertain aetiology should be considered separate from that associated with lichen planus. We also propose a diagnostic algorithm for patients with acquired macular hyperpigmentation.

  13. Associations of OCA2-HERC2 SNPs and haplotypes with human pigmentation characteristics in the Brazilian population.

    PubMed

    Andrade, Edilene S; Fracasso, Nádia C A; Strazza Júnior, Paulo S; Simões, Aguinaldo L; Mendes-Junior, Celso T

    2017-01-01

    Panels composed of Single Nucleotide Polymorphisms (SNPs) in genes related to pigmentation, when associated with different phenotypes, may assist in predicting the physical appearance of an individual, being very useful in forensic caseworks. We evaluated the association of seven OCA2-HERC2 SNPs and haplotypes with pigmentation characteristics (eye, skin, hair and freckles) in the highly admixed and phenotypically heterogeneous Brazilian population. All the seven SNPs evaluated presented one allele associated with phenotypes from at least two pigmentation features and the alternative allele associated with the opposite phenotypes from the same trait. The genotypic associations followed the same pattern for all seven SNPs. Nine haplotypes were observed in our sample and eight were associated with at least two pigmentation traits. Such SNPs and haplotypes could be deemed as good predictors for the presence of freckles and for skin, eye and hair pigmentation in the Brazilian population.

  14. Pigments, Parasites and Personalitiy: Towards a Unifying Role for Steroid Hormones?

    PubMed Central

    Kittilsen, Silje; Johansen, Ida Beitnes; Braastad, Bjarne Olai; Øverli, Øyvind

    2012-01-01

    A surging interest in the evolution of consistent trait correlations has inspired research on pigment patterns as a correlate of behavioural syndromes, or “animal personalities”. Associations between pigmentation, physiology and health status are less investigated as potentially conserved trait clusters. In the current study, lice counts performed on farmed Atlantic salmon Salmo salar naturally infected with ectoparasitic sea lice Lepeophtheirus salmonis showed that individual fish with high incidence of black melanin-based skin spots harboured fewer female sea lice carrying egg sacs, compared to less pigmented fish. There was no significant association between pigmentation and lice at other developmental stages, suggesting that host factors associated with melanin-based pigmentation may modify ectoparasite development to a larger degree than settlement. In a subsequent laboratory experiment a strong negative correlation between skin spots and post-stress cortisol levels was revealed, with less pigmented individuals showing a more pronounced cortisol response to acute stress. The observation that lice prevalence was strongly increased on a fraction of sexually mature male salmon which occurred among the farmed fish further supports a role for steroid hormones as mediators of reduced parasite resistance. The data presented here propose steroid hormones as a proximate cause for the association between melanin-based pigmentation and parasites. Possible fundamental and applied implications are discussed. PMID:22493685

  15. Enamel ultrastructure in pigmented hypomaturation amelogenesis imperfecta.

    PubMed

    Wright, J T; Lord, V; Robinson, C; Shore, R

    1992-10-01

    Hypomaturation amelogenesis imperfecta (AI) is a hereditary condition of enamel that is presumed to result from defects during the maturation stage of enamel development. This study characterized the enamel ultrastructure and enamel crystallite morphology, as well as the distribution of organic material in enamel affected with pigmented hypomaturation AI. Enamel exhibiting autosomal recessive pigmented hypomaturation AI was sectioned or fractured and examined using light microscopy, scanning electron microscopy and transmission electron microscopy. Enamel samples were treated with 30% NaOCl or 8 M urea to remove organic components and determine the effect of deproteinization on crystallite morphology. These were compared with untreated normal enamel samples. The enamel crystallites in hypomaturation AI exhibited considerable variability in size and morphology. Examination of deproteinized tissue indicated that the AI crystallites had a thick coating, presumably of organic or partially mineralized material, which was not visible in normal enamel. The results of this investigation provide further evidence that hypomaturation AI is associated with the retention of organic material that is most probably enamel protein. Enamel protein retention is likely to be involved in the inhibition of normal crystallite growth resulting in the morphological crystallite abnormalities associated with this disorder.

  16. 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

  17. Aging Differences in Ethnic Skin

    PubMed Central

    Buainain De Castro Maymone, Mayra; Kundu, Roopal V.

    2016-01-01

    Aging is an inevitable and complex process that can be described clinically as features of wrinkles, sunspots, uneven skin color, and sagging skin. These cutaneous effects are influenced by both intrinsic and extrinsic factors and often are varied based on ethnic origin given underlying structural and functional differences. The authors sought to provide updated information on facets of aging and how it relates to ethnic variation given innate differences in skin structure and function. Publications describing structural and functional principles of ethnic and aging skin were primarily found through a PubMed literature search and supplemented with a review of textbook chapters. The most common signs of skin aging despite skin type are dark spots, loss of elasticity, loss of volume, and rhytides. Skin of color has many characteristics that make its aging process unique. Those of Asian, Hispanic, and African American descent have distinct facial structures. Differences in the concentration of epidermal melanin makes darkly pigmented persons more vulnerable to dyspigmentation, while a thicker and more compact dermis makes facial lines less noticeable. Ethnic skin comprises a large portion of the world population. Therefore, it is important to understand the unique structural and functional differences among ethnicities to adequately treat the signs of aging. PMID:26962390

  18. Detection of a novel pigment network feature in reticulated black solar lentigo by high-resolution epiluminescence microscopy.

    PubMed

    Haas, Norbert; Hermes, Barbara; Henz, Beate M

    2002-06-01

    Epiluminescence light microscopy (ELM) of pigmented skin lesions has led to a catalog of pigment network (PN) features. The objective of this study was to determine whether high-resolution ELM detects additional pigment structures not seen with conventional ELM. Epiluminescence light microscopy was performed by placing the lens of a standard light microscope directly on the skin surface, with resulting enhanced optical resolution compared with ELM systems currently in general use. Eight reticulated black solar lentigines were studied. All lesions were viewed and analyzed using dermatoscopic criteria for the PN. In addition, they were all photographed, excised, and examined histologically. Two subtypes of black solar lentigines could be distinguished using generally accepted dermatoscopic criteria for the PN. Furthermore, a new pigment structure was detected, namely, pigment spots of equal color, shape, and size, which were regularly superimposed on and juxtaposed to the PN. Clinicopathologic correlation showed these spots to represent individual hyperpigmented corneocytes. Because such cells result from physiologic excessive pigment translocation via the epidermal melanocytic unit, we called them pigmented corneocytes. Pigmented corneocytes were seen in seven of eight black solar lentigines. The ELM technique presented here allows for more detailed analysis and classification of the PN components. Pigmented corneocytes are proposed as an additional dermatoscopic criterion.

  19. Formation of highly toxic hydrogen cyanide upon ruby laser irradiation of the tattoo pigment phthalocyanine blue

    PubMed Central

    Schreiver, Ines; Hutzler, Christoph; Laux, Peter; Berlien, Hans-Peter; Luch, Andreas

    2015-01-01

    Since laser treatment of tattoos is the favored method for the removing of no longer wanted permanent skin paintings, analytical, biokinetics and toxicological data on the fragmentation pattern of commonly used pigments are urgently required for health safety reasons. Applying dynamic headspace—gas chromatography with mass spectrometric detection (DHS—GC/MS) and comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GCxGC—ToF-MS), we identified 1,2-benzene dicarbonitrile, benzonitrile, benzene, and the poisonous gas hydrogen cyanide (HCN) as main fragmentation products emerging dose-dependently upon ruby laser irradiation of the popular blue pigment copper phthalocyanine in suspension. Skin cell viability was found to be significantly compromised at cyanide levels of ≥1 mM liberated during ruby laser irradiation of >1.5 mg/ml phthalocyanine blue. Further, for the first time we introduce pyrolysis-GC/MS as method suitable to simulate pigment fragmentation that may occur spontaneously or during laser removal of organic pigments in the living skin of tattooed people. According to the literature such regular tattoos hold up to 9 mg pigment/cm2 skin. PMID:26243473

  20. Formation of highly toxic hydrogen cyanide upon ruby laser irradiation of the tattoo pigment phthalocyanine blue.

    PubMed

    Schreiver, Ines; Hutzler, Christoph; Laux, Peter; Berlien, Hans-Peter; Luch, Andreas

    2015-08-05

    Since laser treatment of tattoos is the favored method for the removing of no longer wanted permanent skin paintings, analytical, biokinetics and toxicological data on the fragmentation pattern of commonly used pigments are urgently required for health safety reasons. Applying dynamic headspace-gas chromatography with mass spectrometric detection (DHS-GC/MS) and comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GCxGC-ToF-MS), we identified 1,2-benzene dicarbonitrile, benzonitrile, benzene, and the poisonous gas hydrogen cyanide (HCN) as main fragmentation products emerging dose-dependently upon ruby laser irradiation of the popular blue pigment copper phthalocyanine in suspension. Skin cell viability was found to be significantly compromised at cyanide levels of ≥1 mM liberated during ruby laser irradiation of >1.5 mg/ml phthalocyanine blue. Further, for the first time we introduce pyrolysis-GC/MS as method suitable to simulate pigment fragmentation that may occur spontaneously or during laser removal of organic pigments in the living skin of tattooed people. According to the literature such regular tattoos hold up to 9 mg pigment/cm(2) skin.

  1. Formation of highly toxic hydrogen cyanide upon ruby laser irradiation of the tattoo pigment phthalocyanine blue

    NASA Astrophysics Data System (ADS)

    Schreiver, Ines; Hutzler, Christoph; Laux, Peter; Berlien, Hans-Peter; Luch, Andreas

    2015-08-01

    Since laser treatment of tattoos is the favored method for the removing of no longer wanted permanent skin paintings, analytical, biokinetics and toxicological data on the fragmentation pattern of commonly used pigments are urgently required for health safety reasons. Applying dynamic headspace—gas chromatography with mass spectrometric detection (DHS—GC/MS) and comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GCxGC—ToF-MS), we identified 1,2-benzene dicarbonitrile, benzonitrile, benzene, and the poisonous gas hydrogen cyanide (HCN) as main fragmentation products emerging dose-dependently upon ruby laser irradiation of the popular blue pigment copper phthalocyanine in suspension. Skin cell viability was found to be significantly compromised at cyanide levels of ≥1 mM liberated during ruby laser irradiation of >1.5 mg/ml phthalocyanine blue. Further, for the first time we introduce pyrolysis-GC/MS as method suitable to simulate pigment fragmentation that may occur spontaneously or during laser removal of organic pigments in the living skin of tattooed people. According to the literature such regular tattoos hold up to 9 mg pigment/cm2 skin.

  2. Photosynthetic pigments: perplexing persistent prevalence of 'superfluous' pigment production.

    PubMed

    Beale, Samuel I

    2008-04-22

    Phycobilins function as light-harvesting pigments in most cyanobacteria and red algae. Although green cyanobacteria of the genus Prochlorococcus express genes encoding enzymes that direct the synthesis of phycobilins, these pigments do not appear to play a role in light harvesting in Prochlorococcus. Now, it is shown that cyanophages infecting Prochlorococcus also contain genes for phycobilin-synthesizing enzymes, and these are expressed in Prochlorococcus, raising further questions as to the role of phycobilins in the host and the virus.

  3. Tattoo pigment in axillary lymph node mimicking calcification of breast cancer

    PubMed Central

    Matsika, Admire; Srinivasan, Bhuvana; Gray, Janet Meryl; Galbraith, Christine Ruth

    2013-01-01

    A tattoo is defined as the intentional or accidental deposit of pigment into the skin. The phenomenon of skin tattooing is on the rise worldwide and complications of tattooing are increasingly being recognised in diagnostic and clinical medicine. We describe a case of calcification-like changes on mammography resembling that of breast malignancy as a result of tattoo pigment deposition in an axillary lymph node. Recognition of such changes in routine breast screening is crucial to avoid further unnecessary invasive investigations and surgery in such patients. PMID:23929611

  4. The dark brown integumentary pigment of a barnacle (Balanus eburneus). A comparative study.

    PubMed

    Barden, H; Koulish, S

    1983-01-01

    A histochemical analysis involving tinctorial and solubility tests was pursued in conjunction with electron microscopy for the purpose of identifying the dark brown epidermal pigment of a barnacle (Balanus eburneus) as melanin and/or ommochrome. Histochemically, comparisons were made with other brown pigments located in the subcarapal epidermis of another crustacean, the fiddler crab (Uca pugilator), the dorsal skin of the red-backed salamander (Plethodon cinereus), the liver and testis of a slider turtle (Chrysemys sp.) and the substantia nigra of human brain. The solubility properties of the pigment of the two crustacean invertebrates were in general similar to one another and markedly different from the pigment of the three vertebrates. Insolubility in appropriate solvents classified the vertebrate pigment as melanin. The invertebrate pigment, however, which was soluble in the ommochrome solvents, concentrated sulfuric and formic acids and 2-chloroethanol, remained insoluble in the ommochrome solvents, dilute aqueous and methanolic hydrochloric acid and dilute sulfuric acid. On the basis of these solubilities, an unequivocal classification of the invertebrate pigment as either melanin or ommochrome did not appear possible. The tinctorial and electron microscopic properties of the barnacle pigment were also equally ambiguous in regard to its specific classification.

  5. Nail abnormalities in patients with vitiligo*

    PubMed Central

    Topal, Ilteris Oguz; Gungor, Sule; Kocaturk, Ozgur Emek; Duman, Hatice; Durmuscan, Mustafa

    2016-01-01

    Background Vitiligo is an acquired pigmentary skin disorder affecting 0.1-4% of the general population. The nails may be affected in patients with an autoimmune disease such as psoriasis, and in those with alopecia areata. It has been suggested that nail abnormalities should be apparent in vitiligo patients. Objective We sought to document the frequency and clinical presentation of nail abnormalities in vitiligo patients compared to healthy volunteers. We also examined the correlations between nail abnormalities and various clinical parameters. Methods This study included 100 vitiligo patients and 100 healthy subjects. Full medical histories were collected from the subjects, who underwent thorough general and nail examinations. All nail changes were noted. In the event of clinical suspicion of a fungal infection, additional mycological investigations were performed. Results Nail abnormalities were more prevalent in the patients (78%) than in the controls (55%) (p=0.001). Longitudinal ridging was the most common finding (42%), followed by (in descending order): leukonychia, an absent lunula, onycholysis, nail bed pallor, onychomycosis, splinter hemorrhage and nail plate thinning. The frequency of longitudinal ridging was significantly higher in patients than in controls (p<0.001). Conclusions Nail abnormalities were more prevalent in vitiligo patients than in controls. Systematic examination of the nails in such patients is useful because nail abnormalities are frequent. However, the causes of such abnormalities require further study. Longitudinal ridging and leukonychia were the most common abnormalities observed in this study. PMID:27579738

  6. Two-photon absorption and transient photothermal imaging of pigments in tissues

    NASA Astrophysics Data System (ADS)

    Ye, Tong; Fu, Dan; Matthews, Thomas E.; Hong, Lian; Simon, John D.; Warren, Warren S.

    2008-02-01

    As a main pigment in skin tissues, melanin plays an important role in photo-protecting skin from UV radiation. However, melanogenesis may be altered due to disease or environmental factors; for example, sun exposure may cause damage and mutation of melanocytes and induce melanoma. Imaging pigmentation changes may provide invaluable information to catch the malignant transformation in its early stage and in turn improve the prognosis of patients. We have demonstrated previously that transmission mode, two-photon, one- or two-color absorption microscopy could provide remarkable contrast in imaging melanin in skin. In this report we demonstrate significantly improved sensitivity, so that we are now able to image in epi-mode (or back reflection) in two-photon absorption. This improvement makes possible for us to characterize the different types of pigmentation on the skin in vivo at virtually any location. Another finding is that we can also image transient photothermal dynamics due to the light absorption of melanin. By carefully choosing excitation and probe wavelengths, we might be able to image melanin in different structures under different micro-environments in skin, which could provide useful photochemical and photophysical insights in understanding how pigments are involved in photoprotection and photodamage of cells.

  7. Urine - abnormal color

    MedlinePlus

    ... medlineplus.gov/ency/article/003139.htm Urine - abnormal color To use the sharing features on this page, please enable JavaScript. The usual color of urine is straw-yellow. Abnormally colored urine ...

  8. Tooth - abnormal colors

    MedlinePlus

    ... medlineplus.gov/ency/article/003065.htm Tooth - abnormal colors To use the sharing features on this page, please enable JavaScript. Abnormal tooth color is any color other than white to yellowish- ...

  9. Abnormal Head Position

    MedlinePlus

    ... cause. Can a longstanding head turn lead to any permanent problems? Yes, a significant abnormal head posture could cause permanent ... occipitocervical synostosis and unilateral hearing loss. Are there any ... postures? Yes. Abnormal head postures can usually be improved depending ...

  10. Skeletal limb abnormalities

    MedlinePlus

    ... medlineplus.gov/ency/article/003170.htm Skeletal limb abnormalities To use the sharing features on this page, please enable JavaScript. Skeletal limb abnormalities refers to a variety of bone structure problems ...

  11. Skin Infections

    MedlinePlus

    ... to the touch may have yellow drainage Of cellulitis: a red, inflamed area on the skin that is tender to the touch may occur in an area of a scratch or cut redness often spreads rapidly over the skin's surface ...

  12. Sagging Skin

    MedlinePlus

    ... Stretch Marks Sun-damaged Skin Unwanted Hair Unwanted Tattoos Varicose Veins Vitiligo Wrinkles Treatments and Procedures Ambulatory ... Stretch Marks Sun-damaged Skin Unwanted Hair Unwanted Tattoos Varicose Veins Vitiligo Wrinkles Treatments and Procedures Ambulatory ...

  13. Identification and hazard prediction of tattoo pigments by means of pyrolysis-gas chromatography/mass spectrometry.

    PubMed

    Schreiver, Ines; Hutzler, Christoph; Andree, Sarah; Laux, Peter; Luch, Andreas

    2016-07-01

    The implementation of regulation for tattoo ink ingredients across Europe has generated the need for analytical methods suitable to identify prohibited compounds. Common challenges of this subject are the poor solubility and the lack of volatility for most pigments and polymers applied in tattoo inks. Here, we present pyrolysis coupled to online gas chromatography and electron impact ionization mass spectrometry (py-GC/MS) as quick and reliable tool for pigment identification using both purified pigments and tattoo ink formulations. Some 36 organic pigments frequently used in tattoo inks were subjected to py-GC/MS with the aim to establish a pyrogram library. To cross-validate pigment identification, 28 commercially available tattoo inks as well as 18 self-made pigment mixtures were analyzed. Pyrograms of inks and mixtures were evaluated by two different means to work out the most reliable and fastest strategy for an otherwise rather time-consuming data review. Using this approach, the declaration of tattoo pigments currently used on the market could be verified. The pyrolysis library presented here is also assumed suitable to predict decomposition patterns of pigments when affected by other degradation scenarios, such as sunlight exposure or laser irradiation. Thus, the consumers' risk associated with the exposure to toxicologically relevant substances that originate from pigment decomposition in the dermal layers of the skin can be assessed. Differentiation between more or less harmful pigments for this field of application now will become feasible.

  14. Abnormal Uterine Bleeding FAQ

    MedlinePlus

    ... PROBLEMS Abnormal Uterine Bleeding • What is a normal menstrual cycle? • When is bleeding abnormal? • At what ages is ... treat abnormal bleeding? •Glossary What is a normal menstrual cycle? The normal length of the menstrual cycle is ...

  15. Protein, lipid, and DNA radicals to measure skin UVA damage and modulation by melanin.

    PubMed

    Haywood, Rachel; Rogge, Fabrice; Lee, Martin

    2008-03-15

    Afro-Caribbeans have a lower incidence of skin cancer than Caucasians, but the effectiveness of melanin as a photoprotective pigment is debated. We investigated the UVA and solar irradiation of ex vivo human skin and DMPO using electron spin resonance spectroscopy, to determine whether pigmented skin is protected by melanin against free radical damage. Initial ascorbate radicals in Caucasian skin were superseded by lipid and/or protein radical adducts with isotropic (a(H)=1.8 mT) and anisotropic spectra comparable to spectra in irradiated pig fat (a(H)=1.9 mT) and BSA. DNA carbon-centered radical adducts (a(H)=2.3 mT) and a broad singlet were detected in genomic DNA/melanin but were not distinguishable in irradiated Caucasian skin. Protein and lipid radicals (n=6 in Caucasian skin) were minimal in Afro-Caribbean skin (n=4) and intermediate skin pigmentations were variable (n=3). In irradiated Afro-Caribbean skin a shoulder to the melanin radical (also in UVA-irradiated pigmented melanoma cells and genomic DNA/melanin and intrinsic to pheomelanin) was detected. In this sample group, protein (but not lipid) radical adducts decreased directly with pigmentation. ESR/spin trapping methodology has potential for screening skin susceptibility to aging and cancer-related radical damage and for measuring protection afforded by melanin, sunscreens, and antiaging creams.

  16. Skin Aging

    MedlinePlus

    Your skin changes as you age. You might notice wrinkles, age spots and dryness. Your skin also becomes thinner and loses fat, making it ... heal, too. Sunlight is a major cause of skin aging. You can protect yourself by staying out ...

  17. Study of DT-diaphorase in pigment-producing cells.

    PubMed

    Smit, N P; Hoogduijn, M J; Riley, P A; Pavel, S

    1999-11-01

    DT-diaphorase is an FAD-containing enzyme capable of a two-electron reduction of ortho- and paraquinones. Nicotinamide coenzymes (NADH + H+ and NADPH + H+) serve as hydrogen sources in these reactions. The role of DT-diaphorase has been thoroughly investigated in situations when the enzyme is able to reduce exogenous and endogenous quinones, hence protecting the cells against these reactive intermediates. The enzyme has also been studied in connection with its ability to activate some quinoid cytostatics. It is surprising that DT-diaphorase has never been investigated in pigment-producing cells that are known to generate considerable amounts of ortho-quinones. Using a spectrophotometric method we could readily measure the activity of DT-diaphorase in epidermis and various cultured pigment cells. The melanocytes isolated from dark skin showed generally higher DT-diaphorase activity than those from fair skin samples. Also, darkly pigmented congenital naevus cells exhibited higher activity of this enzyme. The most striking was the high DT-diaphorase activity in melanoma cell cultures. In these cells DT-diaphorase activity could be induced by incubation of the cells with 4-hydroxyanisole. A similar effect was seen when a catechol-O-methyltransferase (COMT) inhibitor (3-(3,4-dihydroxy-5-nitrobenzylidene)-2,4-pentanedione (OR-462) was utilised. The induction was inhibited by cyclohexidine.

  18. How does agonistic behaviour differ in albino and pigmented fish?

    PubMed Central

    Horký, Pavel; Wackermannová, Marie

    2016-01-01

    In addition to hypopigmentation of the skin and red iris colouration, albino animals also display distinct physiological and behavioural alterations. However, information on the social interactions of albino animals is rare and has mostly been limited to specially bred strains of albino rodents and animals from unique environments in caves. Differentiating between the effects of albinism and domestication on behaviour in rodents can be difficult, and social behaviour in cave fish changes according to species-specific adaptations to conditions of permanent darkness. The agonistic behaviours of albino offspring of pigmented parents have yet to be described. In this study, we observed agonistic behaviour in albino and pigmented juvenile Silurus glanis catfish. We found that the total number of aggressive interactions was lower in albinos than in pigmented catfish. The distance between conspecifics was also analysed, and albinos showed a tendency towards greater separation from their same-coloured conspecifics compared with pigmented catfish. These results demonstrate that albinism can be associated with lower aggressiveness and with reduced shoaling behaviour preference, as demonstrated by a tendency towards greater separation of albinos from conspecifics. PMID:27114883

  19. Multimode spectroscopy for the in vivo assessment of post-inflammatory pigmentation: preliminary observations

    NASA Astrophysics Data System (ADS)

    Zhao, Jianhua; Alkhayat, Hana; Al Robaee, Ahmad; Zeng, Haishan; McLean, David I.; Lui, Harvey

    2006-02-01

    Although post-inflammatory pigmentation (PIH) is a common acquired skin disorder, however, its mechanism still remains unclear. In this paper, multimode optical spectroscopic techniques including diffuse reflectance spectroscopy, fluorescence spectroscopy and Raman spectroscopy have been used to probe the morphologic and biochemical changes associated with PIH. Both pigmented skin and the adjacent normal skin were measured for paired analysis. Distinctive spectral features were observed which may provide the potentials for identifying the mechanism of PIH. The diffuse reflectance spectrum was also converted into the CIE standard L*a*b* color system. The melanin and the hemoglobin content in the PIH were quantitatively derived from the diffusive reflectance spectrum using the Stamatas-Kollias algorithm. It was found that PIH always has a lower value in L* and more melanin and hemoglobin content which is consistent with clinical appearance of dark skin as perceived by the human eye.

  20. Sensitive skin.

    PubMed

    Misery, L; Loser, K; Ständer, S

    2016-02-01

    Sensitive skin is a clinical condition defined by the self-reported facial presence of different sensory perceptions, including tightness, stinging, burning, tingling, pain and pruritus. Sensitive skin may occur in individuals with normal skin, with skin barrier disturbance, or as a part of the symptoms associated with facial dermatoses such as rosacea, atopic dermatitis and psoriasis. Although experimental studies are still pending, the symptoms of sensitive skin suggest the involvement of cutaneous nerve fibres and neuronal, as well as epidermal, thermochannels. Many individuals with sensitive skin report worsening symptoms due to environmental factors. It is thought that this might be attributed to the thermochannel TRPV1, as it typically responds to exogenous, endogenous, physical and chemical stimuli. Barrier disruptions and immune mechanisms may also be involved. This review summarizes current knowledge on the epidemiology, potential mechanisms, clinics and therapy of sensitive skin.

  1. Proliferative and toxic effects of ultraviolet light and inflammation on epidermal pigment cells

    SciTech Connect

    Nordlund, J.J.; Ackles, A.E.; Traynor, F.F.

    1981-10-01

    The ear of the mouse is useful for studying the effects of ultraviolet light on epidermal pigment cells. The quantity of light penetrating into the skin causing an inflammatory response can be assessed easily by measuring with an engineering calipers the swelling of the ear. The inflammatory response of the ear exhibits a linear relationship to the dose of light delivered. We observed that doses of shortwave ultraviolet light which are noninflammatory when repeated at daily intervals induce moderate to severe inflammation. Small doses of psoralen and prolonged exposure to UVA (PUVA) were more inflammatory than larger amounts of psoralen and short exposure to light. Doses of shortwave ultraviolet light and PUVA which produce only a minimal inflammation of the skin stimulate the proliferation of epidermal melanocytes. In contrast, PUVA in doses sufficiently large to cause a marked inflammatory reaction in the skin seems injurious to pigment cells and kills them or causes only a minimal proliferative response. The inflammatory reaction itself does not seem to stimulate or inhibit the proliferation of melanocytes. Prostaglandins A, E, and F2 alpha have no effect on the proliferation of epidermal pigment cells. In contrast, dimethyl sulfoxide (DMSO) and allergic contact dermatitis increase the numerical density of pigment cells. Steroids may block the function of the enzyme tyrosinase. Our experiments indicate that pigment cells, like many other varieties of cells, are susceptible to injury and can be killed at least by large doses of PUVA.

  2. Sensitive skin: mechanisms and diagnosis.

    PubMed

    Primavera, G; Berardesca, E

    2005-02-01

    Sensitive skin is a condition of subjective cutaneous hyperreactivity to environmental factors. Subjects experiencing this condition report exaggerated reactions when their skin is in contact with cosmetics, soaps and sunscreens, and they often report worsening after exposure to dry and cold climate. Although no sign of irritation is commonly detected, itching, burning, stinging and a tight sensation are constantly present. Generally substances that are not commonly considered irritants are involved in this abnormal response. They include many ingredients of cosmetics such as: dimethyl sulfoxide, benzoyl peroxide preparations, salicylic acid, propylene glycol, amyldimethylaminobenzoic acid and 2-ethoxyethyl methoxycinnamate. Sensitive skin and subjective irritation are widespread but still far from being completely defined and understood. The aim of this paper is to summarize the relevant literature in order to elucidate the underlying mechanisms of sensitive skin and the best testing methodologies for investigation of sensitive skin.

  3. Artificial skin in perspective: concepts and applications.

    PubMed

    Brohem, Carla A; Cardeal, Laura B da Silva; Tiago, Manoela; Soengas, María S; Barros, Silvia B de Moraes; Maria-Engler, Silvya S

    2011-02-01

    Skin, the largest organ of the human body, is organized into an elaborate layered structure consisting mainly of the outermost epidermis and the underlying dermis. A subcutaneous adipose-storing hypodermis layer and various appendages such as hair follicles, sweat glands, sebaceous glands, nerves, lymphatics, and blood vessels are also present in the skin. These multiple components of the skin ensure survival by carrying out critical functions such as protection, thermoregulation, excretion, absorption, metabolic functions, sensation, evaporation management, and aesthetics. The study of how these biological functions are performed is critical to our understanding of basic skin biology such as regulation of pigmentation and wound repair. Impairment of any of these functions may lead to pathogenic alterations, including skin cancers. Therefore, the development of genetically controlled and well characterized skin models can have important implications, not only for scientists and physicians, but also for manufacturers, consumers, governing regulatory boards and animal welfare organizations. As cells making up human skin tissue grow within an organized three-dimensional (3D) matrix surrounded by neighboring cells, standard monolayer (2D) cell cultures do not recapitulate the physiological architecture of the skin. Several types of human skin recombinants, also called artificial skin, that provide this critical 3D structure have now been reconstructed in vitro. This review contemplates the use of these organotypic skin models in different applications, including substitutes to animal testing.

  4. Roentgenographic abnormalities in Rocky Mountain Spotted Fever.

    PubMed

    McCook, T A; Briley, C; Ravin, C E

    1982-02-01

    Rock Mountain spotted fever (RMSF) is a tick-borne rickettsial disease which produces a widespread vasculitis. A mortality of 7% to 13% has been reported in the United States which is due at least in part to delay in diagnosis and appropriate treatment. The classic features of this disease include a history of tick bite with the clinical presentation of skin rash and fever in association with thrombocytopenia. Few reports have emphasized the radiologic chest abnormalities in this disease or their relationship to thrombocytopenia. We review 70 cases of RMSF with abnormal roentgenographic features and their pathologic correlation.

  5. A Germline Mutation in BLOC1S3/Reduced Pigmentation Causes a Novel Variant of Hermansky-Pudlak Syndrome (HPS8)

    PubMed Central

    Morgan, Neil V.; Pasha, Shanaz; Johnson, Colin A.; Ainsworth, John R.; Eady, Robin A. J.; Dawood, Ban; McKeown, Carole; Trembath, Richard C.; Wilde, Jonathan; Watson, Steve P.; Maher, Eamonn R.

    2006-01-01

    Hermansky-Pudlak syndrome (HPS) is genetically heterogeneous, and mutations in seven genes have been reported to cause HPS. Autozygosity mapping studies were undertaken in a large consanguineous family with HPS. Affected individuals displayed features of incomplete oculocutaneous albinism and platelet dysfunction. Skin biopsy demonstrated abnormal aggregates of melanosomes within basal epidermal keratinocytes. A homozygous germline frameshift mutation in BLOC1S3 (p.Gln150ArgfsX75) was identified in all affected individuals. BLOC1S3 mutations have not been previously described in patients with HPS, but BLOC1S3 encodes a subunit of the biogenesis of lysosome-related organelles complex 1 (BLOC-1). Mutations in other BLOC-1 subunits have been associated with an HPS phenotype in humans and/or mouse, and a nonsense mutation in the murine orthologue of BLOC1S3 causes the reduced pigmentation (rp) model of HPS. Interestingly, eye pigment formation is reported to be normal in rp, but we found visual defects (nystagmus, iris transilluminancy, foveal hypoplasia, reduced visual acuity, and evidence of optic pathway misrouting) in affected individuals. These findings define a novel form of human HPS (HPS8) and extend genotype-phenotype correlations in HPS. PMID:16385460

  6. Human pigmentation genes and their response to solar UV radiation.

    PubMed

    Sturm, R A

    1998-11-09

    Identification and characterisation of the genes involved in melanin pigment formation, together with the study of how their action is influenced by exposure to UV radiation, is providing a molecular understanding of the process of skin photoprotection through tanning. The mechanisms underlying this change in epidermal melanin involve both a transcriptional response of the pigmentation genes and post-translational control of the melanin biosynthetic pathway. UV rays are known to interact with numerous molecules within cells, and among these the photochemical reactions involving lipids and DNA are implicated in modulating melanogenesis. The combination of DNA damage, the formation of diacylglycerol, and the action of the melanocyte stimulating hormone receptor are all likely to be involved in UV-induced tanning.

  7. Skin aging and dry skin.

    PubMed

    Hashizume, Hideo

    2004-08-01

    Skin aging appears to be the result of both scheduled and continuous "wear and tear" processes that damage cellular DNA and proteins. Two types of aging, chronological skin aging and photoaging, have distinct clinical and histological features. Chronological skin aging is a universal and inevitable process characterized primarily by physiologic alterations in skin function. In this case, keratinocytes are unable to properly terminally differentiate to form a functional stratum corneum, and the rate of formation of neutral lipids that contribute to the barrier function slows, causing dry, pale skin with fine wrinkles. In contrast, photoaging results from the UVR of sunlight and the damage thus becomes apparent in sun-exposed skin. Characteristics of this aging type are dry and sallow skin displaying fine wrinkles as well as deep furrows, resulting from the disorganization of epidermal and dermal components associated with elastosis and heliodermatitis. Understanding of the functions of the skin and the basic principles of moisturizer use and application is important for the prevention of skin aging. Successful treatment of dry skin with appropriate skin care products gives the impression of eternal youth.

  8. Photocurrent generation by dye-sensitized solar cells using natural pigments.

    PubMed

    Armendáriz-Mireles, Eddie Nahúm; Rocha-Rangel, Enrique; Caballero-Rico, Frida; Ramírez-de-León, José Alberto; Vázquez, Manuel

    2017-01-01

    The development of photovoltaic panels has improved the conversion of solar radiation into electrical energy. This paper deals with the electrical and thermal characteristics (voltage, current, and temperature) of photovoltaic solar cells sensitized with natural pigments (dye-sensitized solar cell, DSSC) based on a titanium dioxide semiconductor. Several natural pigments (blackberry, beets, eggplant skin, spinach, flame tree flower, papaya leaf, and grass extracts) were evaluated to determine their sensitizing effect on titanium dioxide. The results showed the great potential of natural pigments for use in solar cells. The best results were obtained with the blackberry pigment, reaching a value of 7.1 mA current, open-circuit voltage (Voc ) of 0.72 V in 2 cm(2) , and fill factor (ff) of 0.51 in the DSSC. This performance is well above than that currently offers by actual cells.

  9. Pigmented Bowen’s disease presenting with a “starburst” pattern

    PubMed Central

    Maione, Vincenzo; Errichetti, Enzo; Roussel, Sara Laurent; Lebbé, Celeste

    2016-01-01

    Pigmented Bowen’s disease (pBD) is an uncommon in situ squamous cell carcinoma of the skin usually presenting as a dark scaly plaque involving chronically exposed sites, which is not uncommonly mistaken for other similar pigmented lesions, such as melanoma, pigmented basal cell carcinoma or seborrheic keratosis [1,2]. Dermoscopy has been proven to improve its diagnosis by showing several findings, i.e., gray/brownish dots in linear arrangement, scales, coiled vessels, focal/multifocal amorphous hypopigmentation and bluish structureless areas [1,2]. However, pBD may sometimes display dermoscopic features which are typical of other pigmented lesions, thus making its recognition quite troublesome despite the use of dermoscopy [1,2]. We report a case of pBD with a “starburst” pattern, discussing its dermoscopic differential diagnosis. PMID:27867748

  10. SLC24A5, a putative cation exchanger, affects pigmentation in zebrafish and humans.

    PubMed

    Lamason, Rebecca L; Mohideen, Manzoor-Ali P K; Mest, Jason R; Wong, Andrew C; Norton, Heather L; Aros, Michele C; Jurynec, Michael J; Mao, Xianyun; Humphreville, Vanessa R; Humbert, Jasper E; Sinha, Soniya; Moore, Jessica L; Jagadeeswaran, Pudur; Zhao, Wei; Ning, Gang; Makalowska, Izabela; McKeigue, Paul M; O'donnell, David; Kittles, Rick; Parra, Esteban J; Mangini, Nancy J; Grunwald, David J; Shriver, Mark D; Canfield, Victor A; Cheng, Keith C

    2005-12-16

    Lighter variations of pigmentation in humans are associated with diminished number, size, and density of melanosomes, the pigmented organelles of melanocytes. Here we show that zebrafish golden mutants share these melanosomal changes and that golden encodes a putative cation exchanger slc24a5 (nckx5) that localizes to an intracellular membrane, likely the melanosome or its precursor. The human ortholog is highly similar in sequence and functional in zebrafish. The evolutionarily conserved ancestral allele of a human coding polymorphism predominates in African and East Asian populations. In contrast, the variant allele is nearly fixed in European populations, is associated with a substantial reduction in regional heterozygosity, and correlates with lighter skin pigmentation in admixed populations, suggesting a key role for the SLC24A5 gene in human pigmentation.

  11. Sectoral iris heterochromia and retinal pigment variation in 13q-syndrome.

    PubMed

    Kutzbach, Beth; Mendelsohn, Nancy; Rath, Pamela; Summers, C Gail

    2007-10-01

    Chromosome 13q deletion syndrome is characterized by growth retardation, cognitive delays, and organ and musculoskeletal deformities. Typical ocular associations include retinoblastoma, microphthalmia, and colobomas. We report a case of bilateral iris heterochromia and retinal pigment abnormalities in a child with 13q-syndrome.

  12. Radiant solar energy and the function of black homeotherm pigmentation: an hypothesis.

    PubMed

    Hamilton, W J; Heppner, F

    1967-01-13

    White zebra finches exposed to artificial sunlight used an average of 22.9 percent less energy after they were dyed black. The hypothesis that black homeotherm coloration functions primarily to maximize absorption of radiant solar energy is suggested. This hypothesis may explain the dark skin pigmentation of certain human populations.

  13. Clinicoepidemiological study of pigmented purpuric dermatoses

    PubMed Central

    Sharma, Lata; Gupta, S.

    2012-01-01

    Background: Pigmented purpuric dermatoses (PPD) are a group of vascular disorders with varied manifestations which cause concern and are resistant to treatment. The literature is still lacking in clinicoepidemiological studies. Aim: To study the epidemiology, etiological, host and environmental factors, clinical manifestations, its variations, and the type prevalent in this part of the world. Materials and Methods: All cases of PPD were selected for the study from Skin and Venereal Disease, Out Patient Department between January 2008 and June 2009. Their history, examination, hematological investigations, and, in a few, histopathology findings were also recorded and data obtained were evaluated statistically. Results: There were 100 cases of PPD of total 55 323 patients (0.18%). There were 79 males and 21 females between 11 and 66 years. They were working as police men, security guards, barber, chemist, teachers, students, farmers, businessmen, and housewives. In a majority, there was a history of prolonged standing in day-to-day work. Purpuric, brownish pigmented, lichenoid or atrophic lesions were seen depending upon the type of PPD on lower parts of one or both lower limbs. Blood investigations were normal. Schamberg's disease was seen in ninety five, Lichen aureus in three, lichenoid dermatosis and Majocchi's disease in one case each. Discussion: Three clinical types of PPD were diagnosed which may represent different features of the same disease. Cell-mediated immunity, immune complexes, capillary fragility, gravitational forces, venous hypertension, focal infection, clothing, contact allergy to dyes, and drug intake have been incriminating factors in the past. Patient's occupation and environmental factors may also be considered contributory in precipitating the disease. Conclusions: The study revealed the problem of PPD in this geographical area, its magnitude, clinical presentation, the type prevalent, and possible aggravating factors to be kept in mind

  14. Sunscreens: topical and systemic approaches for protection of human skin against harmful effects of solar radiation

    SciTech Connect

    Pathak, M.A.

    1982-09-01

    This review deals with topical and systemic approaches for protection of human skin against the harmful effects of solar radiation. Two concerns about the deleterious effects of sun exposure involve: (1) acute effects (e.g., sunburn and drug-induced phototoxicity) and (2) potential long-term risks of repeated sun exposures leading to development of solar elastosis, keratoses, induction of both nonmelanoma and melanoma skin cancer, and alteration of immune responses and functions. Action spectra of normal and abnormal reactions of human skin to acute and chronic effects of solar radiation are presented with a view to helping the physician prescribe the appropriate sunscreens. Factors that influence acute effects of sunburn are reviewed. Various artificial methods effective in minimizing or preventing harmful effects of solar radiation, both in normal individuals and in patients with photosensitivity-related problems, are discussed. Emphasis is placed on the commercially available chemical sunscreens and their properties. Sun protection factor (SPF) values of several brand-name formulations determined with a solar simulator under indoor conditions (laboratory) and with solar radiation under natural, field conditions are presented. Factors responsible for variations of SPF values observed under indoor and outdoor conditions are reviewed. Systemic photoprotective agents and their limitations are outlined. The photobiology of melanin pigmentation (the tanning reaction) is briefly discussed, with emphasis on the dangers of using quick-tanning lotions for stimulation of the tanning reaction.

  15. Case Report of a Large Pigmented Epithelioid Melanocytoma With Suspected Lymph Node Metastases

    PubMed Central

    Akita, Rie; Morita, Daiki; Numajiri, Toshiaki

    2016-01-01

    Objective: Pigmented epithelioid melanocytoma was proposed by Zembowicz et al in 2004 including lesions previously diagnosed as human animal-type melanoma and epithelioid blue nevus. Tumors are composed of epithelioid and spindled melanocytes with heavy pigmentation. Methods: We report a case of pigmented epithelioid melanocytoma in 47-year-old Asian woman. The tumor sized 10 × 6 × 2 cm on the anterior aspect of right lower leg. On resecting surgery, we also found black pigmented lymph nodes in the groin area on harvesting skin graft. Results: Histological examination showed a typical figure for pigmented epithelioid melanocytoma. In groin area, melanocytes were observed only in the lymph node capsule. Thus, we conclude that melanocytes in the capsule of this case could not be associated with metastasis. The patient is doing well 2 years after the surgery, with no evidence of recurrence or distant metastases. Conclusions: Pigmented epithelioid melanocytoma is a rare, heavily pigmented, borderline, melanocytic tumor with infiltrative borders. It has potential for frequent metastases but shows an indolent clinical course. PMID:28066518

  16. cis-Regulatory changes in Kit ligand expression and parallel evolution of pigmentation in sticklebacks and humans.

    PubMed

    Miller, Craig T; Beleza, Sandra; Pollen, Alex A; Schluter, Dolph; Kittles, Rick A; Shriver, Mark D; Kingsley, David M

    2007-12-14

    Dramatic pigmentation changes have evolved within most vertebrate groups, including fish and humans. Here we use genetic crosses in sticklebacks to investigate the parallel origin of pigmentation changes in natural populations. High-resolution mapping and expression experiments show that light gills and light ventrums map to a divergent regulatory allele of the Kit ligand (Kitlg) gene. The divergent allele reduces expression in gill and skin tissue and is shared by multiple derived freshwater populations with reduced pigmentation. In humans, Europeans and East Asians also share derived alleles at the KITLG locus. Strong signatures of selection map to regulatory regions surrounding the gene, and admixture mapping shows that the KITLG genomic region has a significant effect on human skin color. These experiments suggest that regulatory changes in Kitlg contribute to natural variation in vertebrate pigmentation, and that similar genetic mechanisms may underlie rapid evolutionary change in fish and humans.

  17. Skin optics

    SciTech Connect

    van Gemert, M.J.; Jacques, S.L.; Sterenborg, H.J.; Star, W.M.

    1989-12-01

    Quantitative dosimetry in the treatment of skin disorders with (laser) light requires information on propagation of light in the skin related to the optical properties of the individual skin layers. This involves the solution of the integro-differential equation of radiative transfer in a model representing skin geometry, as well as experimental methods to determine the optical properties of each skin layer. These activities are unified under the name skin optics. This paper first reviews the current status of tissue optics, distinguishing between the cases of: dominant absorption, dominant scattering, and scattering about equal to absorption. Then, previously published data as well as some current unpublished data on (human) stratum corneum, epidermis and dermis, have been collected and/or (re)analyzed in terms of absorption coefficient, scattering coefficient, and anisotropy factor of scattering. The results are that the individual skin layers show strongly forward scattering (anisotropy factors between 0.7 and 0.9). The absorption and scattering data show that for all wavelengths considered scattering is much more important than absorption. Under such circumstances, solutions to the transport equation for a multilayer skin model and finite beam laser irradiation are currently not yet available. Hence, any quantitative dosimetry for skin treated with (laser) light is currently lacking.

  18. Metamaterial-based sensor for skin disease diagnostics

    NASA Astrophysics Data System (ADS)

    La Spada, L.; Iovine, R.; Tarparelli, R.; Vegni, L.

    2013-05-01

    Skin absorption properties, under diseases conditions, are modified due to the structural variations of chromophores and pigments. The measurement of such different absorptions can be a useful tool for the recognition of different skin diseases. In this study the design of a multi-resonant metamaterial-based sensor operating in the optical frequency range is presented. The sensor has been designed, in order to have multiple specific resonant frequencies, tuned to the skin components spectral characteristics. A change in the frequency amplitude of the sensor response is related to the different absorption rate of skin chromophores and pigments. A new analytical model, describing the multi-resonant sensor behaviour, is developed. Good agreement among analytical and numerical results was achieved. Full-wave simulations have validated the capability of the proposed sensor to identify different skin diseases.

  19. Occurrence and formation kinetics of pyranomalvidin-procyanidin dimer pigment in Merlot red wine: impact of acidity and oxygen concentrations.

    PubMed

    Pechamat, Laurent; Zeng, Liming; Jourdes, Michael; Ghidossi, Rémy; Teissedre, Pierre-Louis

    2014-02-19

    Once released from red grape skins, anthocyanins undergo various chemical reactions leading to the formation of more stable pigments such as pyranoanthocyanin, as well as other derivatives. Among these pigments, pyranoanthocyanins linked directly to flavanol dimers have been detected and identified in aged Port wine but not in dry red wine. These pigments are very important with regard to the wine color evolution since they are involved in wine color evolution and stabilization. During this investigation, the occurrence in dry red wine of two pyranomalvidin-procyanidin dimer has been established by low and high resolution HPLC-UV-MS analysis. Moreover, the impact of acidity and oxygen levels on their formation in red wine has been estimated. After four months of evolution, the results showed that, for the same pH, the quantity of this pigment was correlated with oxygen concentrations. Moreover, for the same quantity of oxygen, the concentration of this pigment was related to the acidity level.

  20. Skin findings in newborns

    MedlinePlus

    Newborn skin characteristics; Infant skin characteristics; Neonatal care - skin ... the first few weeks of the baby's life. Newborn skin will vary, depending on the length of the pregnancy. Premature infants have thin, transparent skin. The skin of a ...

  1. A case of pigmented Bowen's disease*

    PubMed Central

    Vivan, Márcia Maria; Hirata, Sérgio Henrique; do Nascimento, Liliane Santos; Enokihara, Milvia Maria Simões e Silva

    2017-01-01

    Pigmented Bowen's disease is a rare subtype of Bowen's disease. Clinically it presents as a slow-growing, well-defined, hyperpigmented plaque, and should be included as a differential diagnosis of other pigmented lesions. The authors describe a challenging case of pigmented Bowen's disease with non-diagnostic dermscopy findings. PMID:28225972

  2. 21 CFR 73.352 - Paracoccus pigment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Paracoccus pigment. 73.352 Section 73.352 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.352 Paracoccus pigment. (a) Identity. (1) The color additive paracoccus pigment consists of the heat-killed, dried cells of a nonpathogenic and nontoxicogenic strain...

  3. 21 CFR 178.3725 - Pigment dispersants.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Pigment dispersants. 178.3725 Section 178.3725... Certain Adjuvants and Production Aids § 178.3725 Pigment dispersants. Subject to the provisions of this regulation, the substances listed in this section may be safely used as pigment dispersants in...

  4. 21 CFR 178.3725 - Pigment dispersants.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Pigment dispersants. 178.3725 Section 178.3725... Certain Adjuvants and Production Aids § 178.3725 Pigment dispersants. Subject to the provisions of this regulation, the substances listed in this section may be safely used as pigment dispersants in...

  5. 21 CFR 73.352 - Paracoccus pigment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Paracoccus pigment. 73.352 Section 73.352 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.352 Paracoccus pigment. (a) Identity. (1) The color additive paracoccus pigment consists of the heat-killed, dried cells of a nonpathogenic and nontoxicogenic strain...

  6. 21 CFR 178.3725 - Pigment dispersants.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Pigment dispersants. 178.3725 Section 178.3725... Certain Adjuvants and Production Aids § 178.3725 Pigment dispersants. Subject to the provisions of this regulation, the substances listed in this section may be safely used as pigment dispersants in...

  7. 21 CFR 73.352 - Paracoccus pigment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Paracoccus pigment. 73.352 Section 73.352 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.352 Paracoccus pigment. (a) Identity. (1) The color additive paracoccus pigment consists of the heat-killed, dried cells of a nonpathogenic and nontoxicogenic strain...

  8. 21 CFR 178.3725 - Pigment dispersants.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Pigment dispersants. 178.3725 Section 178.3725... § 178.3725 Pigment dispersants. Subject to the provisions of this regulation, the substances listed in this section may be safely used as pigment dispersants in food-contact materials....

  9. 21 CFR 73.352 - Paracoccus pigment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Paracoccus pigment. 73.352 Section 73.352 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.352 Paracoccus pigment. (a) Identity. (1) The color additive paracoccus pigment consists of the heat-killed, dried cells of a nonpathogenic and nontoxicogenic strain...

  10. 21 CFR 73.352 - Paracoccus pigment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Paracoccus pigment. 73.352 Section 73.352 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.352 Paracoccus pigment. (a) Identity. (1) The color additive paracoccus pigment consists of the heat-killed, dried cells of a nonpathogenic and nontoxicogenic strain...

  11. 21 CFR 178.3725 - Pigment dispersants.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Pigment dispersants. 178.3725 Section 178.3725 Food... Certain Adjuvants and Production Aids § 178.3725 Pigment dispersants. Subject to the provisions of this regulation, the substances listed in this section may be safely used as pigment dispersants in...

  12. Morphological Characters and Transcriptome Profiles Associated with Black Skin and Red Skin in Crimson Snapper (Lutjanus erythropterus)

    PubMed Central

    Zhang, Yan-Ping; Wang, Zhong-Duo; Guo, Yu-Song; Liu, Li; Yu, Juan; Zhang, Shun; Liu, Shao-Jun; Liu, Chu-Wu

    2015-01-01

    In this study, morphology observation and illumina sequencing were performed on two different coloration skins of crimson snapper (Lutjanus erythropterus), the black zone and the red zone. Three types of chromatophores, melanophores, iridophores and xanthophores, were organized in the skins. The main differences between the two colorations were in the amount and distribution of the three chromatophores. After comparing the two transcriptomes, 9200 unigenes with significantly different expressions (ratio change ≥ 2 and q-value ≤ 0.05) were found, of which 5972 were up-regulated in black skin and 3228 were up-regulated in red skin. Through the function annotation, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of the differentially transcribed genes, we excavated a number of uncharacterized candidate pigment genes as well as found the conserved genes affecting pigmentation in crimson snapper. The patterns of expression of 14 pigment genes were confirmed by the Quantitative real-time PCR analysis between the two color skins. Overall, this study shows a global survey of the morphological characters and transcriptome analysis of the different coloration skins in crimson snapper, and provides valuable cellular and genetic information to uncover the mechanism of the formation of pigment patterns in snappers. PMID:26569232

  13. BACILLUS PYOCYANEUS AND ITS PIGMENTS

    PubMed Central

    Jordan, Edwin O.

    1899-01-01

    The principal conclusions that seem to me justified are as follows: 1. The fluorescent pigment formed by some varieties of B. pyocyaneus is produced under conditions identical with those governing the production of the pigment by other "fluorescent bacteria." 2. The production of pyocyanin is not dependent upon the presence of either phosphate or sulfate in the culture medium. It is formed in non-proteid as well as in proteid media, but is not a necessary accompaniment of the metabolic activities of the organism (e. g. tartrate solution). 3. The power of producing pyocyanin under conditions of artificial cultivation is lost sooner than the fluorescigenic power. 4. There are greater natural and acquired differences in pyocyanigenic power than in fluorescigenic. 5. The fluorescent pigment may be oxidized slowly by the action of light and air as well as by reagents into a yellow pigment, and pyocyanin may be similarly oxidized into a black pigment. 6. A convenient separation of B. pyocyaneus into four varieties would be the following: var. α, pyocyanigenic and fluorescigenic (most common); var. β, pyocyanigenic only (rare); var. γ, fluorescigenic only (not uncommon, closely related to "B. fluorescens liquefaciens"); var. δ, non-chromogenic. 7. Except for the occasional loss of one or another function the different varieties are not so plastic as sometimes assumed, and cannot be readily converted into one another by subjection to varying conditions of life. 8. The signification and correlation of the almost countless physiological variations among the members of this group in respect to growth in gelatin, behavior to temperature, indol production, etc., remain to be determined. It is not yet clear that the variations in chromogenic power can be in any way correlated with the presence or absence of other physiological functions. PMID:19866929

  14. Structurally abnormal human autosomes

    SciTech Connect

    1993-12-31

    Chapter 25, discusses structurally abnormal human autosomes. This discussion includes: structurally abnormal chromosomes, chromosomal polymorphisms, pericentric inversions, paracentric inversions, deletions or partial monosomies, cri du chat (cat cry) syndrome, ring chromosomes, insertions, duplication or pure partial trisomy and mosaicism. 71 refs., 8 figs.

  15. Skin Infections

    MedlinePlus

    ... it can get infected by them. Some common types of skin infections are Bacterial: Cellulitis and impetigo. Staphylococcal infections can also affect the skin. Viral: Shingles, warts, and herpes simplex Fungal: Athlete's foot and yeast infections Parasitic: Body lice, head lice, and scabies ...

  16. Skin barrier in rosacea.

    PubMed

    Addor, Flavia Alvim Sant'Anna

    2016-01-01

    Recent studies about the cutaneous barrier demonstrated consistent evidence that the stratum corneum is a metabolically active structure and also has adaptive functions, may play a regulatory role in the inflammatory response with activation of keratinocytes, angiogenesis and fibroplasia, whose intensity depends primarily on the intensity the stimulus. There are few studies investigating the abnormalities of the skin barrier in rosacea, but the existing data already show that there are changes resulting from inflammation, which can generate a vicious circle caused a prolongation of flare-ups and worsening of symptoms. This article aims to gather the most relevant literature data about the characteristics and effects of the state of the skin barrier in rosacea.

  17. Skin barrier in rosacea*

    PubMed Central

    Addor, Flavia Alvim Sant'Anna

    2016-01-01

    Recent studies about the cutaneous barrier demonstrated consistent evidence that the stratum corneum is a metabolically active structure and also has adaptive functions, may play a regulatory role in the inflammatory response with activation of keratinocytes, angiogenesis and fibroplasia, whose intensity depends primarily on the intensity the stimulus. There are few studies investigating the abnormalities of the skin barrier in rosacea, but the existing data already show that there are changes resulting from inflammation, which can generate a vicious circle caused a prolongation of flare-ups and worsening of symptoms. This article aims to gather the most relevant literature data about the characteristics and effects of the state of the skin barrier in rosacea. PMID:26982780

  18. Risk of Skin Cancer from Space Radiation. Chapter 11

    NASA Technical Reports Server (NTRS)

    Cucinotta, Francis A.; Kim, Myung-Hee Y.; George, Kerry A.; Wu, Hong-Lu

    2003-01-01

    We review the methods for estimating the probability of increased incidence of skin cancers from space radiation exposure, and describe some of the individual factors that may contribute to risk projection models, including skin pigment, and synergistic effects of combined ionizing and UV exposure. The steep dose gradients from trapped electrons, protons, and heavy ions radiation during EVA and limitations in EVA dosimetry are important factors for projecting skin cancer risk of astronauts. We estimate that the probability of increased skin cancer risk varies more than 10-fold for individual astronauts and that the risk of skin cancer could exceed 1 % for future lunar base operations for astronauts with light skin color and hair. Limitations in physical dosimetry in estimating the distribution of dose at the skin suggest that new biodosimetry methods be developed for responding to accidental overexposure of the skin during future space missions.

  19. 'Skin Trade': Genealogy of Anti-ageing 'Whiteness Therapy' in Colonial Medicine.

    PubMed

    Mire, Amina

    2014-01-01

    This article investigates the extent to which the emerging trend of do-it-yourself anti-ageing skin-whitening products represents a re-articulation of Western colonial concerns with environmental pollution and racial degeneracy into concern with gendered vulnerability. This emerging market is a multibillion dollar industry anchored in the USA, but expanding globally. Do-it-yourself anti-ageing skin-whitening products purport to address the needs of those looking to fight the visible signs of ageing, often promising to remove hyper-pigmented age spots from women's skin, and replace it with ageless skin, free from pigmentation. In order to contextualize the investigation of do-it-yourself anti-ageing skin-whitening practice and discourse, this article draws from the literature in colonial commodity culture, colonial tropical medicine, the contemporary anti-ageing discourse, and advertisements for anti-ageing skin-whitening products. First, it argues that the framing of the biomedicalization of ageing as a pigmentation problem caused by deteriorating environmental conditions and unhealthy lifestyle draws tacitly from European colonial concerns with the European body's susceptibility to tropical diseases, pigmentation disorders, and racial degeneration. Second, the article argues that the rise of do-it-yourself anti-ageing skin-whitening commodities that promise to whiten, brighten, and purify the ageing skin of women and frames the visible signs of ageing in terms of pigmentation pathology.

  20. Melanocytic aggregation in the skin: diagnostic clues from lentigines to melanoma.

    PubMed

    de Giorgi, Vincenzo; Sestini, Serena; Massi, Daniela; Lotti, Torello

    2007-07-01

    Pigmented skin lesions are among the most common skin lesions. Among them, melanocytic proliferations are morphologically diverse and their behavior may be difficult to discern with certainty. Researchers must be able to distinguish melanocytic from nonmelanocytic pigmented skin lesions and, in particular, benign from malignant lesions. The majority of these lesions can be diagnosed with ease; however, a minority of cases is difficult and have potential for error. The authors have systematically analyzed the clinical and dermoscopic features of melanocytic skin lesions, so as to increase in vivo diagnostic accuracy.

  1. 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

  2. SCF/c-kit signaling is required in 12-O-tetradecanoylphorbol-13-acetate-induced migration and differentiation of hair follicle melanocytes for epidermal pigmentation.

    PubMed

    Qiu, Weiming; Yang, Ke; Lei, Mingxing; Yan, Hongtao; Tang, Hui; Bai, Xiufeng; Yang, Guihong; Lian, Xiaohua; Wu, Jinjin

    2015-05-01

    Hair follicle melanocyte stem cells (McSCs) are responsible for hair pigmentation and also function as a major melanocyte reservoir for epidermal pigmentation. However, the molecular mechanism promoting McSCs for epidermal pigmentation remains elusive. 12-O-tetradecanoylphorbol-13-acetate (TPA) mimics key signaling involved in melanocyte growth, migration and differentiation. We therefore investigated the molecular basis for the contribution of hair follicle McSCs to epidermal pigmentation using the TPA induction model. We found that repetitive TPA treatment of female C57BL/6 mouse dorsal skin induced epidermal pigmentation by increasing the number of epidermal melanocytes. Particularly, TPA treatment induced McSCs to initiate proliferation, exit the stem cell niche and differentiate. We also demonstrated that TPA promotes melanoblast migration and differentiation in vitro. At the molecular level, TPA treatment induced robust expression of stem cell factor (SCF) in keratinocytes and c-kit in melanoblasts and melanocytes. Administration of ACK2, a neutralizing antibody against the Kit receptor, suppressed mouse epidermal pigmentation, decreased the number of epidermal melanocytes, and inhibited melanoblast migration. Taken together, our data demonstrate that TPA promotes the expansion, migration and differentiation of hair follicle McSCs for mouse epidermal pigmentation. SCF/c-kit signaling was required for TPA-induced migration and differentiation of hair follicle melanocytes. Our findings may provide an excellent model to investigate the signaling mechanisms regulating epidermal pigmentation from mouse hair follicle McSCs, and a potential therapeutic option for skin pigmentation disorders.

  3. Electrochemical Skin Conductance Correlates with Skin Nerve Fiber Density

    PubMed Central

    Novak, Peter

    2016-01-01

    Purpose: Electrochemical skin conductance (ESC) using reverse iontophoresis and chronoamperometry has been used to evaluate abnormal function of small fibers. How ESC correlates with loss of small fibers in skin is unclear. Methods: This was a prospective, blinded study. The primary outcome measure was the correlation between ESC at the feet and results of skin biopsies including epidermal nerve fiber density (ENFD) and sweat gland nerve fiber density (SGNFD) at the distal leg. ESC, ENFD, and SGNFD data were normalized by adjusting for weight. The secondary outcome measures were the correlation between ESC and the following variables: quantitative sudomotor axon reflex test (QSART) and symptom scales (neuropathy, pain and autonomic). Results: Eighty-one patients (mean ± sd): age = 53.3 ± 17.3, men/women = 25/56 were enrolled in the study. ESC was reduced in subjects with abnormally low ENFD (ENFD normal/abnormal, ESC = 1.17 ± 0.27/0.87 ± 0.34 μSiemens/kg, p < 0.0008) and abnormally low SGNFD (SGNFD normal/abnormal ESC = 1.09 ± 0.34/0.78 ± 0.3 μSiemens/kg, p < 0.0003). ESC correlated with ENFD (ρ = 0.73, p = 0.0001) and SGNFD (ρ = 0.64, p = 0.0001). ESC did not correlate with symptom scales. Conclusion: ESC is diminished in subjects who have a reduced number of small fibers in the skin and the ESC reduction is proportional to ENFD and SGNFD. ESC can be useful in detecting loss of small nerve fibers. PMID:27605912

  4. Fuzzy description of skin lesions

    NASA Astrophysics Data System (ADS)

    Laskaris, Nikolaos; Ballerini, Lucia; Fisher, Robert B.; Aldridge, Ben; Rees, Jonathan

    2010-02-01

    We propose a system for describing skin lesions images based on a human perception model. Pigmented skin lesions including melanoma and other types of skin cancer as well as non-malignant lesions are used. Works on classification of skin lesions already exist but they mainly concentrate on melanoma. The novelty of our work is that our system gives to skin lesion images a semantic label in a manner similar to humans. This work consists of two parts: first we capture they way users perceive each lesion, second we train a machine learning system that simulates how people describe images. For the first part, we choose 5 attributes: colour (light to dark), colour uniformity (uniform to non-uniform), symmetry (symmetric to non-symmetric), border (regular to irregular), texture (smooth to rough). Using a web based form we asked people to pick a value of each attribute for each lesion. In the second part, we extract 93 features from each lesions and we trained a machine learning algorithm using such features as input and the values of the human attributes as output. Results are quite promising, especially for the colour related attributes, where our system classifies over 80% of the lesions into the same semantic classes as humans.

  5. Estimating physiological skin parameters from hyperspectral signatures.

    PubMed

    Vyas, Saurabh; Banerjee, Amit; Burlina, Philippe

    2013-05-01

    We describe an approach for estimating human skin parameters, such as melanosome concentration, collagen concentration, oxygen saturation, and blood volume, using hyperspectral radiometric measurements (signatures) obtained from in vivo skin. We use a computational model based on Kubelka-Munk theory and the Fresnel equations. This model forward maps the skin parameters to a corresponding multiband reflectance spectra. Machine-learning-based regression is used to generate the inverse map, and hence estimate skin parameters from hyperspectral signatures. We test our methods using synthetic and in vivo skin signatures obtained in the visible through the short wave infrared domains from 24 patients of both genders and Caucasian, Asian, and African American ethnicities. Performance validation shows promising results: good agreement with the ground truth and well-established physiological precepts. These methods have potential use in the characterization of skin abnormalities and in minimally-invasive prescreening of malignant skin cancers.

  6. Estimating physiological skin parameters from hyperspectral signatures

    NASA Astrophysics Data System (ADS)

    Vyas, Saurabh; Banerjee, Amit; Burlina, Philippe

    2013-05-01

    We describe an approach for estimating human skin parameters, such as melanosome concentration, collagen concentration, oxygen saturation, and blood volume, using hyperspectral radiometric measurements (signatures) obtained from in vivo skin. We use a computational model based on Kubelka-Munk theory and the Fresnel equations. This model forward maps the skin parameters to a corresponding multiband reflectance spectra. Machine-learning-based regression is used to generate the inverse map, and hence estimate skin parameters from hyperspectral signatures. We test our methods using synthetic and in vivo skin signatures obtained in the visible through the short wave infrared domains from 24 patients of both genders and Caucasian, Asian, and African American ethnicities. Performance validation shows promising results: good agreement with the ground truth and well-established physiological precepts. These methods have potential use in the characterization of skin abnormalities and in minimally-invasive prescreening of malignant skin cancers.

  7. Availability and Utilization of Pigments from Microalgae.

    PubMed

    Begum, Hasina; Yusoff, Fatimah Md; Banerjee, Sanjoy; Khatoon, Helena; Shariff, Mohamed

    2016-10-02

    Microalgae are the major photosynthesizers on earth and produce important pigments that include chlorophyll a, b and c, β-carotene, astaxanthin, xanthophylls, and phycobiliproteins. Presently, synthetic colorants are used in food, cosmetic, nutraceutical, and pharmaceutical industries. However, due to problems associated with the harmful effects of synthetic colorants, exploitation of microalgal pigments as a source of natural colors becomes an attractive option. There are various factors such as nutrient availability, salinity, pH, temperature, light wavelength, and light intensity that affect pigment production in microalgae. This paper reviews the availability and characteristics of microalgal pigments, factors affecting pigment production, and the application of pigments produced from microalgae. The potential of microalgal pigments as a source of natural colors is enormous as an alternative to synthetic coloring agents, which has limited applications due to regulatory practice for health reasons.

  8. Photoacoustic discrimination of vascular and pigmented lesions using classical and Bayesian methods

    NASA Astrophysics Data System (ADS)

    Swearingen, Jennifer A.; Holan, Scott H.; Feldman, Mary M.; Viator, John A.

    2010-01-01

    Discrimination of pigmented and vascular lesions in skin can be difficult due to factors such as size, subungual location, and the nature of lesions containing both melanin and vascularity. Misdiagnosis may lead to precancerous or cancerous lesions not receiving proper medical care. To aid in the rapid and accurate diagnosis of such pathologies, we develop a photoacoustic system to determine the nature of skin lesions in vivo. By irradiating skin with two laser wavelengths, 422 and 530 nm, we induce photoacoustic responses, and the relative response at these two wavelengths indicates whether the lesion is pigmented or vascular. This response is due to the distinct absorption spectrum of melanin and hemoglobin. In particular, pigmented lesions have ratios of photoacoustic amplitudes of approximately 1.4 to 1 at the two wavelengths, while vascular lesions have ratios of about 4.0 to 1. Furthermore, we consider two statistical methods for conducting classification of lesions: standard multivariate analysis classification techniques and a Bayesian-model-based approach. We study 15 human subjects with eight vascular and seven pigmented lesions. Using the classical method, we achieve a perfect classification rate, while the Bayesian approach has an error rate of 20%.

  9. Holographic films from carotenoid pigments

    NASA Astrophysics Data System (ADS)

    Toxqui-López, S.; Lecona-Sánchez, J. F.; Santacruz-Vázquez, C.; Olivares-Pérez, A.; Fuentes-Tapia, I.

    2014-02-01

    Carotenoids pigments presents in pineapple can be more than just natural dyes, which is one of the applications that now at day gives the chemical industry. In this research shown that can be used in implementing of holographic recording Films. Therefore we describe the technique how to obtain this kind of pigments trough spay drying of natural pineapple juice, which are then dissolved with water in a proportion of 0.1g to 1mL. The obtained sample is poured into glass substrates using the gravity method, after a drying of 24 hours in laboratory normal conditions the films are ready. The films are characterized by recording transmission holographic gratings (LSR 445 NL 445 nm) and measuring the diffraction efficiency holographic parameter. This recording material has good diffraction efficiency and environmental stability.

  10. Visual Pigments of Goldfish Cones

    PubMed Central

    Hárosi, Ferenc I.; MacNichol, Edward F.

    1974-01-01

    Freshly isolated retinal photoreceptors of goldfish were studied microspectrophotometrically. Absolute absorptance spectra obtained from dark-adapted cone outer segments reaffirm the existence of three spectrally distinct cone types with absorption maxima at 455 ± 3,530 ± 3, and 625 ± 5 nm. These types were found often recognizable by gross cellular morphology. Side-illuminated cone outer segments were dichroic. The measured dichroic ratio for the main absorption band of each type was 2–3:1. Rapidly bleached cells revealed spectral and dichroic transitions in regions near 400–410, 435–455, and 350–360 nm. These photoproducts decay about fivefold as fast as the intermediates in frog rods. The spectral maxima of photoproducts, combined with other evidence, indicate that retinene2 is the chromophore of all three cone pigments. The average specific optical density for goldfish cone outer segments was found to be 0.0124 ± 0.0015/µm. The spectra of the blue-, and green-absorbing cones appeared to match porphyropsin standards with half-band width Δν = 4,832 ± 100 cm–1. The red-absorbing spectrum was found narrower, having Δν = 3,625 ± 100 cm–1. The results are consistent with the notion that visual pigment concentration within the outer segments is about the same for frog rods and goldfish cones, but that the blue-, and green-absorbing pigments possess molar extinctions of 30,000 liter/mol cm. The red-absorbing pigment was found to have extinction of 40,000 liter/mol cm, assuming invariance of oscillator strength among the three cone spectra. PMID:4817352

  11. Nanoscience of an ancient pigment.

    PubMed

    Johnson-McDaniel, Darrah; Barrett, Christopher A; Sharafi, Asma; Salguero, Tina T

    2013-02-06

    We describe monolayer nanosheets of calcium copper tetrasilicate, CaCuSi(4)O(10), which have strong near-IR luminescence and are amenable to solution processing methods. The facile exfoliation of bulk CaCuSi(4)O(10) into nanosheets is especially surprising in view of the long history of this material as the colored component of Egyptian blue, a well-known pigment from ancient times.

  12. "Jeopardy" in Abnormal Psychology.

    ERIC Educational Resources Information Center

    Keutzer, Carolin S.

    1993-01-01

    Describes the use of the board game, Jeopardy, in a college level abnormal psychology course. Finds increased student interaction and improved application of information. Reports generally favorable student evaluation of the technique. (CFR)

  13. Skin Cancer

    MedlinePlus

    ... exposure to ultraviolet light, which is found in sunlight and in lights used in tanning salons.What ... the safe-sun guidelines.1. Avoid the sun.Sunlight damages your skin. The sun is strongest during ...

  14. Skin graft

    MedlinePlus

    ... that need skin grafts to heal Venous ulcers, pressure ulcers , or diabetic ulcers that do not heal Very ... chap 17. Read More Burns Patient Instructions Preventing pressure ulcers Surgical wound care - open Review Date 3/13/ ...

  15. Your Skin

    MedlinePlus

    ... wear sunscreen and protective clothing, such as a hat, to prevent painful sunburns. Protecting your skin now ... happens in a split second, without you ever thinking about it. previous continue Dermis = Lots of Blood ...

  16. Skin Cancer

    MedlinePlus

    ... States. The two most common types are basal cell cancer and squamous cell cancer. They usually form on the head, face, ... If not treated, some types of skin cancer cells can spread to other tissues and organs. Treatments ...

  17. Evaluation of digital dermoscopy in a pigmented lesion clinic: clinician versus computer assessment of malignancy risk.

    PubMed

    Boldrick, Jennifer C; Layton, Christle J; Nguyen, Josephine; Swetter, Susan M

    2007-03-01

    Digital dermoscopy systems employ computer-based algorithms to quantitate features of pigmented skin lesions (PSLs) and provide an assessment of malignancy risk. We evaluated interobserver concordance of PSL malignancy risk between a pigmented lesion specialist and an artificial neural network (ANN)-based automated digital dermoscopy system. While digital dermoscopy provides a reliable means of image capture, storage, and comparison of PSLs over time, the ANN algorithm requires further training and validation before the malignancy risk assessment feature can be widely used in clinical practice.

  18. Personal observation of skin disorders in malnutrition.

    PubMed

    Lee, Benjamin Y; Hogan, Daniel J; Ursine, Susonne; Yanamandra, Krishne; Bocchini, Joseph A

    2006-01-01

    This is a description of some unknown skin disorders found by a physician inmate in a concentration camp, 1958 to 1962. After prolonged semistarvation and ultraheavy physical labor, skin lesions developed among the inmates including cutaneous pigmentation overlying bony prominence, buccal membrane pigmentation, palmoplantar keratoderma with fissures, palmar crease clefts, nail layering, intra-nail hemorrhage, and so on. These lesions responded dramatically to nutrition therapy, including dietary improvement, yeast administration, or thiamin injection. Thiamin deficiency was confirmed to be one of major etiologic factors, whereas the deficiency of niacin or riboflavin also played a part. In the pediatric case with palmar crease clefts, both thiamin and niacin were dramatically effective. No laboratory data could be provided.

  19. Senescent Skin

    PubMed Central

    Kushniruk, William

    1974-01-01

    The cutaneous surface is continually influenced by aging and environmental factors. A longer life span is accompanied by an increase in the frequency of problems associated with aging skin. Although most of these changes and lesions are not life threatening, the premalignant lesions must be recognized and treated. The common aging and actinic skin changes are discussed and appropriate management is described. ImagesFig. 1Fig. 2Fig. 3Fig. 4 PMID:20469067

  20. Changes in biophysical properties of the skin following radiotherapy for breast cancer.

    PubMed

    Hu, Stephen Chu-Sung; Hou, Ming-Feng; Luo, Kuei-Hau; Chuang, Hung-Yi; Wei, Shu-Yi; Chen, Gwo-Shing; Chiang, Wenchang; Huang, Chih-Jen

    2014-12-01

    Acute radiation dermatitis is a common adverse effect in patients undergoing radiotherapy for breast cancer. However, the effects of radiotherapy on biophysical properties of the skin have rarely been investigated. In this prospective cohort study, we seek to determine the effects of radiotherapy for breast cancer on skin biophysical parameters. We measured various skin biophysical parameters (skin hydration, pH, sebum level, pigmentation, and blood flow) in 144 breast cancer patients by non-invasive techniques before and after radiotherapy. The measurements were simultaneously performed on the irradiated breast and the corresponding contralateral unirradiated breast for comparison. Following radiotherapy, the irradiated breast showed a significant decrease in skin hydration, increase in skin pH, increase in pigmentation, and increase in cutaneous blood flow. The contralateral unirradiated breast showed a slight increase in pigmentation but no significant changes in any of the other biophysical parameters after radiotherapy. No significant associations were found between patient characteristics (diabetes mellitus, hypertension, type of surgery, chemotherapy, hormone therapy) and changes in skin biophysical parameters following radiotherapy. In conclusion, radiation therapy for breast cancer induces measurable and significant changes in biophysical properties of the skin including hydration, pH, pigmentation, and blood flow. These findings give us a greater understanding of the effects of ionizing radiation on skin physiology, and provide non-invasive and objective methods to assess radiation dermatitis.

  1. Analysis of differentially expressed genes associated with tryptophan-dependent pigment synthesis in M. furfur by cDNA subtraction technology.

    PubMed

    Hort, W; Lang, S; Brunke, S; Mayser, P; Hube, B

    2009-05-01

    Malassezia species are associated with pityriasis versicolor (PV) and its depigmented variant pityriasis versicolor alba (PVa), widespread fungal skin infections in humans. The pathogenesis of PV and PVa remains unclear, including their clinical and histological symptoms such as hyper- and depigmentation, reduced responsiveness to ultraviolet radiation and lack of inflammatory reaction despite high fungal load. Pigments produced by M. furfur are possibly involved in the pathogenesis of PV. In vitro, M. furfur produces a wide range of pigments and fluorochromes when cultured with tryptophan as the sole nitrogen source. We have begun to analyse the molecular basis of pigment production by searching for genes associated with tryptophan-based pigment production. A suppression subtractive hybridization (SSH) protocol was used to identify genes expressed in M. furfur cells producing pigments, but not in non-induced cells. SSH was performed 3 and 5 h after onset of pigment induction. Up-regulation of genes in the pigment-producing cells was confirmed by reverse northern analysis. More than 1,500 cDNA sequences of both the indicated time points were analysed. We identified a wide variety of genes associated with metabolism and several genes with unknown function are specifically expressed during pigment production. Furthermore, a fraction of genes possibly involved in different steps of the newly discovered indolic pathway of M. furfur were expressed in pigment producing cells. These data provide the first molecular insight into pigment production of M. furfur.

  2. Evaluation of skin cancer risk for lunar and Mars missions

    NASA Astrophysics Data System (ADS)

    Kim, M. Y.; George, K. A.; Cucinotta, F. A.

    Methods for estimating the probability of excess incidence of skin cancer from space radiation exposure, must consider the variability of skin doses at specific anatomical areas, and the individual factors that may contribute to risk projection models, including skin pigment, and synergistic effects from combined ionizing radiation and UV exposure. Using the multiplicative risk model for transferring the Japanese survivor data to the US population, epidemiological data for the increased risk for skin locations exposed to combined UV and ionizing radiation, and models of space radiation environments, transport, and anatomical shielding, we estimate the skin cancer risk for future lunar and Mars missions. Our model projects that individual variations in the probability for increased skin cancer risk varies more than 10-fold and that an excess cancer risk greater than 1% could occur for astronauts with light skin and hair color exposed to medium class solar particle events during future lunar base operations, or from galactic cosmic rays on Mars missions.

  3. Melanin photosensitizes ultraviolet light (UVC) DNA damage in pigmented cells

    SciTech Connect

    Huselton, C.A.; Hill, H.Z. )

    1990-01-01

    Melanins, pigments of photoprotection and camouflage, are very photoreactive and can both absorb and emit active oxygen species. Nevertheless, black skinned individuals rarely develop skin cancer and melanin is assumed to act as a solar screen. Since DNA is the target for solar carcinogenesis, the effect of melanin on Ultraviolet (UV)-induced thymine lesions was examined in mouse melanoma and carcinoma cells that varied in melanin content. Cells prelabeled with 14C-dThd were irradiated with UVC; DNA was isolated, purified, degraded to bases by acid hydrolysis and analyzed by HPLC. Thymine dimers were detected in all of the extracts of irradiated cells. Melanotic and hypomelanotic but not mammary carcinoma cell DNA from irradiated cells contained hydrophilic thymine derivatives. The quantity of these damaged bases was a function of both the UVC dose and the cellular melanin content. One such derivative was identified by gas chromatography-mass spectroscopy as thymine glycol. The other appears to be derived from thymine glycol by further oxidation during acid hydrolysis of the DNA. The finding of oxidative DNA damage in melanin-containing cells suggests that melanin may be implicated in the etiology of caucasian skin cancer, particularly melanoma. Furthermore, the projected decrease in stratospheric ozone could impact in an unanticipated deleterious manner on dark-skinned individuals.

  4. Melanin photosensitizes ultraviolet light (UVC) DNA damage in pigmented cells.

    PubMed

    Huselton, C A; Hill, H Z

    1990-01-01

    Melanins, pigments of photoprotection and camouflage, are very photoreactive and can both absorb and emit active oxygen species. Nevertheless, black skinned individuals rarely develop skin cancer and melanin is assumed to act as a solar screen. Since DNA is the target for solar carcinogenesis, the effect of melanin on Ultraviolet (UV)-induced thymine lesions was examined in mouse melanoma and carcinoma cells that varied in melanin content. Cells prelabeled with 14C-dThd were irradiated with UVC; DNA was isolated, purified, degraded to bases by acid hydrolysis and analyzed by HPLC. Thymine dimers were detected in all of the extracts of irradiated cells. Melanotic and hypomelanotic but not mammary carcinoma cell DNA from irradiated cells contained hydrophilic thymine derivatives. The quantity of these damaged bases was a function of both the UVC dose and the cellular melanin content. One such derivative was identified by gas chromatography-mass spectroscopy as thymine glycol. The other appears to be derived from thymine glycol by further oxidation during acid hydrolysis of the DNA. The finding of oxidative DNA damage in melanin-containing cells suggests that melanin may be implicated in the etiology of caucasian skin cancer, particularly melanoma. Furthermore, the projected decrease in stratospheric ozone could impact in an unanticipated deleterious manner on dark-skinned individuals.

  5. Influence of hydration on dihydroxyacetone-induced pigmentation of stratum corneum.

    PubMed

    Nguyen, Bach-Cuc; Kochevar, Irene E

    2003-04-01

    Dihydroxyacetone, the browning ingredient in sunless tanning formulations, reacts with amino acids in the outer stratum corneum to form a mixture of high molecular weight pigments. Our initial observations indicated that high hydration of dihydroxyacetone-treated skin completely inhibited development of pigmentation. To investigate the mechanism underlying this effect, studies were carried out in isolated murine epidermis, polyvinyl alcohol/lysine films, and lysine in glycerol/water solvent. Murine epidermis treated with dihydroxyacetone showed a biphasic dependence on relative humidity: maximum pigmentation developed at 84% relative humidity and minimum pigmentation at 0% and 100% relative humidity. Filaggrin proteolysis, which shows a similar dependence on relative humidity and provides free amino acids in the outer stratum corneum, did not account for the relative humidity dependence of dihydroxyacetone pigmentation. A similar biphasic pigmentation response was obtained when polyvinyl alcohol film containing lysine was treated with dihydroxyacetone and incubated at various relative humidities, indicating that the structure of the stratum corneum was not a major factor. To remove the influence of the matrix, the reaction of dihydroxyacetone with lysine was followed at varying concentrations of water in mixed glycerol/buffer solvent. Again, greater pigment formation was found at an intermediate level of water (6% vol/vol) and little pigmentation at 0% and 100% water content. These results are consistent with a requirement for water at low relative humidity, which facilitates formation of free amine groups needed for the initial reaction with dihydroxyacetone, and with inhibition of the dehydration reactions by water through the law of mass action at high relative humidity.

  6. Comparison of pigment cell ultrastructure and organisation in the dermis of marble trout and brown trout, and first description of erythrophore ultrastructure in salmonids.

    PubMed

    Djurdjevič, Ida; Kreft, Mateja Erdani; Sušnik Bajec, Simona

    2015-11-01

    Skin pigmentation in animals is an important trait with many functions. The present study focused on two closely related salmonid species, marble trout (Salmo marmoratus) and brown trout (S. trutta), which display an uncommon labyrinthine (marble-like) and spot skin pattern, respectively. To determine the role of chromatophore type in the different formation of skin pigment patterns in the two species, the distribution and ultrastructure of chromatophores was examined with light microscopy and transmission electron microscopy. The presence of three types of chromatophores in trout skin was confirmed: melanophores; xanthophores; and iridophores. In addition, using correlative microscopy, erythrophore ultrastructure in salmonids was described for the first time. Two types of erythrophores are distinguished, both located exclusively in the skin of brown trout: type 1 in black spot skin sections similar to xanthophores; and type 2 with a unique ultrastructure, located only in red spot skin sections. Morphologically, the difference between the light and dark pigmentation of trout skin depends primarily on the position and density of melanophores, in the dark region covering other chromatophores, and in the light region with the iridophores and xanthophores usually exposed. With larger amounts of melanophores, absence of xanthophores and presence of erythrophores type 1 and type L iridophores in the black spot compared with the light regions and the presence of erythrophores type 2 in the red spot, a higher level of pigment cell organisation in the skin of brown trout compared with that of marble trout was demonstrated. Even though the skin regions with chromatophores were well defined, not all the chromatophores were in direct contact, either homophilically or heterophilically, with each other. In addition to short-range interactions, an important role of the cellular environment and long-range interactions between chromatophores in promoting adult pigment pattern

  7. Phytochemistry: structure of the blue cornflower pigment.

    PubMed

    Shiono, Masaaki; Matsugaki, Naohiro; Takeda, Kosaku

    2005-08-11

    The same anthocyanin pigment makes roses red but cornflowers blue, a phenomenon that has so far not been entirely explained. Here we describe the X-ray crystal structure of the cornflower pigment, which reveals that its blue colour arises from a complex of six molecules each of anthocyanin and flavone, with one ferric iron, one magnesium and two calcium ions. We believe that this tetrametal complex may represent a previously undiscovered type of supermolecular pigment.

  8. Identification of the silkworm quail gene reveals a crucial role of a receptor guanylyl cyclase in larval pigmentation.

    PubMed

    Yuasa, Masashi; Kiuchi, Takashi; Banno, Yutaka; Katsuma, Susumu; Shimada, Toru

    2016-01-01

    Diverse color patterns on the integument of lepidopteran larvae play important roles in their survival through camouflage, mimicry, sexual signaling, and aposematism. In the silkworm Bombyx mori, many color pattern variations have been preserved in inbred strains making them a good model for elucidating the molecular mechanisms that underlie color pattern formation. In this study, we focused on the silkworm quail (q) mutant, which exhibits abnormalities in multiple pigment biosynthesis pathways. Positional cloning of the q gene revealed that disruption of a guanylyl cyclase gene, BmGC-I, is responsible for its abnormal pigmentation. In q mutants, we identified a 16-bp deletion in the BmGC-I transcript, resulting in the production of a premature stop codon. Knockout of the BmGC-I gene resulted in the q-like abnormal pigmentation, thereby demonstrating that the BmGC-I gene is involved in the pigment biosynthesis pathway in the integument. Moreover, quantitative reverse transcription polymerase chain reaction showed that BmGC-I was strongly expressed in the fourth instar on day 2. Our results suggest that BmGC-I deficiency affects the pigment biosynthesis pathway, which supports the involvement of guanylyl cyclase in larval coloration.

  9. Skin microbiome and skin disease: the example of rosacea.

    PubMed

    Picardo, Mauro; Ottaviani, Monica

    2014-01-01

    The imbalance and/or the perturbation of the microbial populations that colonize the skin and that contribute to its defense may represent one of the causes of the development of noninfectious skin diseases. Atopic dermatitis, psoriasis, acne, and rosacea can be listed among these kinds of pathologies. In particular, considering that microbes have been long addressed as having a role in rosacea, this common dermatosis can be an interesting model to evaluate the correlation between microbiome alterations and the occurrence of clinical manifestations. Different microorganisms have been suggested to have a role in rosacea, but no direct correlation with the incidence of the pathology has been clearly defined. Skin microbiome composition is crucial for the correct skin immune functions and recent findings indicate an abnormal activation of innate immune system associated with the rosacea. The enhanced expression of toll-like receptor 2 in the epidermis of rosacea patients can represent a possible explanation for the amplified inflammatory response to external stimuli observed during the disease. In addition, significantly higher small intestinal bacterial overgrowth prevalence in rosacea subjects has been found and its eradication has been associated with a regression of the skin lesions. In conclusion, both skin and gut microbiome seem to have a role, even if synergistic with other factors, in the pathogenesis of rosacea. A deeper knowledge of human microbiome composition and microbe-host interactions will contribute to clarify the mechanism of development of rosacea and possibly will provide innovative therapeutic approaches.

  10. TRP Channels in Skin Biology and Pathophysiology

    PubMed Central

    Caterina, Michael J.; Pang, Zixuan

    2016-01-01

    Ion channels of the Transient Receptor Potential (TRP) family mediate the influx of monovalent and/or divalent cations into cells in response to a host of chemical or physical stimuli. In the skin, TRP channels are expressed in many cell types, including keratinocytes, sensory neurons, melanocytes, and immune/inflammatory cells. Within these diverse cell types, TRP channels participate in physiological processes ranging from sensation to skin homeostasis. In addition, there is a growing body of evidence implicating abnormal TRP channel function, as a product of excessive or deficient channel activity, in pathological skin conditions such as chronic pain and itch, dermatitis, vitiligo, alopecia, wound healing, skin carcinogenesis, and skin barrier compromise. These diverse functions, coupled with the fact that many TRP channels possess pharmacologically accessible sites, make this family of proteins appealing therapeutic targets for skin disorders. PMID:27983625

  11. Non-photosynthetic pigments as potential biosignatures

    NASA Astrophysics Data System (ADS)

    Schwieterman, E. W.; Cockell, C. S.; Meadows, V. S.

    2014-03-01

    Photosynthetic organisms on Earth produce potentially detectable surface reflectance biosignatures due in part to the spectral location and strength of pigment absorption. However, life on Earth uses pigments for a multitude of purposes other than photosynthesis, including coping with extreme environments. Macroscopic environments exist on Earth where the surface reflectance is significantly altered by a nonphotosynthetic pigment, such as the case of hypersaline lakes and ponds (Oren et al. 1992). Here we explore the nature and potential detectability of non-photosynthetic pigments in disk-averaged planetary observations using a combination of laboratory measurements and archival reflectance spectra, along with simulated broadband photometry and spectra. The in vivo visible reflectance spectra of a cross section of pigmented microorganisms are presented to illustrate the spectral diversity of biologically produced pigments. Synthetic broadband colors are generated to show a significant spread in color space. A 1D radiative transfer model (Meadows & Crisp 1996; Crisp 1997) is used to approximate the spectra of scenarios where pigmented organisms are widespread on planets with Earth-like atmospheres. Broadband colors are revisited to show that colors due to surface reflectivity are not robust to the addition of scattering and absorption effects from the atmosphere. We consider a èbest case' plausible scenario for the detection of nonphotosynthetic pigments by using the Virtual Planetary Laboratory's 3D spectral Earth model (Robinson et al. 2011) to explore the detectability of the surface biosignature produced by pigmented halophiles that are widespread on an Earth-analog planet.

  12. Melanin pigmented solar absorbing surfaces

    SciTech Connect

    Gallas, J.M.; Eisner, M.

    1980-01-01

    Selectivity enhancement is shown to result for melanin, a black biopolymer pigment, for sufficiently low sample density. The effect is proposed to follow from a consideration of the evanescent waves associated with the total internal reflection phenomenon. A relationship is discussed among powder density, pH and the paramagnetic properties of melanin; this relationship is shown to be consistent with, and offer support to an amino-acid side group proposed earlier as part of the melanin structure. A brief discussion is also presented on the optical properties of melanin and the relative importance of quinhydrone, a change transfer complex believed to exist in the polymeric structure of melanin.

  13. Management of pigmented gingiva in child patient: a new era to the pediatric dentistry.

    PubMed

    Namdeoraoji Bahadure, Rakesh; Singh, Parul; Jain, Eesha; Khurana, Heena; Badole, Gautam

    2013-09-01

    Gingival health in the form of size, shape, consistency and appearance are essential components responsible for an attractive smile as well as may cause unpleasant appearance. Melanin pigmentation often occurs in the gingiva as a result of an abnormal deposition of melanin which can compromise the confidence level from the age of childhood. The present article describes and discusses the two cases of gingival melanin pigmentation in 12 and 13 years of female patient and their early surgical intervention with successful follow-up of 9 and 6 months. Patients were instructed to prevent sun exposure, intake of hot foods or beverages like cold drinks, tea, coffee and brushing immediately after surgery. How to cite this article: Bahadure RN, Singh P, Jain E, Khurana H, Badole G. Management of Pigmented Gingiva in Child Patient: A New Era to the Pediatric Dentistry. Int J Clin Pediatr Dent 2013;6(3):197-200.

  14. Management of Pigmented Gingiva in Child Patient: A New Era to the Pediatric Dentistry

    PubMed Central

    Singh, Parul; Jain, Eesha; Khurana, Heena; Badole, Gautam

    2013-01-01

    ABSTRACT Gingival health in the form of size, shape, consistency and appearance are essential components responsible for an attractive smile as well as may cause unpleasant appearance. Melanin pigmentation often occurs in the gingiva as a result of an abnormal deposition of melanin which can compromise the confidence level from the age of childhood. The present article describes and discusses the two cases of gingival melanin pigmentation in 12 and 13 years of female patient and their early surgical intervention with successful follow-up of 9 and 6 months. Patients were instructed to prevent sun exposure, intake of hot foods or beverages like cold drinks, tea, coffee and brushing immediately after surgery. How to cite this article: Bahadure RN, Singh P, Jain E, Khurana H, Badole G. Management of Pigmented Gingiva in Child Patient: A New Era to the Pediatric Dentistry. Int J Clin Pediatr Dent 2013;6(3):197-200. PMID:25206222

  15. Skin Transcriptome Profiles Associated with Skin Color in Chickens

    PubMed Central

    Zhang, Jianqin; Liu, Fuzhu; Cao, Junting; Liu, Xiaolin

    2015-01-01

    Nutritional and medicinal benefits have been attributed to the consumption of tissues from the black-boned chickens in oriental countries. Lueyang black-boned chicken is one of the native chicken breeds. However, some birds may instead have white or lighter skin, which directly causes economic losses every year. Previous studies of pigmentation have focused on a number of genes that may play important roles in coat color regulation. Illumina2000 sequencing technology was used to catalog the global gene expression profiles in the skin of the Lueyang chicken with white versus black skin. A total of 18,608 unigenes were assembled from the reads obtained from the skin of the white and black chickens. A total of 649 known genes were differentially expressed in the black versus white chickens, with 314 genes that were up regulated and 335 genes that were down-regulated, and a total of 162 novel genes were differentially expressed in the black versus white chickens, consisting of 73 genes that were up-regulated (including 4 highly expressed genes that were expressed exclusively in the skin of the black chickens) and 89 genes that were down-regulated. There were also a total of 8 known coat-color genes expressed in previous studies (ASIP, TYR, KIT, TYRP1, OCA2, KITLG, MITF and MC1R). In this study, 4 of which showed greater expression in the black chickens, and several were up-regulated, such as KIT, ASIP, TYR and OCA2. To our surprise, KITLG, MITF and MC1R showed no significant difference in expression between the black- and white-skinned chickens, and the expression of TYRP1 was not detected in either skin color. The expression of ASIP, TYR, KIT, TYRP1, OCA2, KITLG, MITF and MC1R was validated by real-time quantitative polymerase chain reaction (qPCR), and the results of the qPCR were consistent with the RNA-seq. This study provides several candidate genes that may be associated with the development of black versus white skin. More importantly, the fact that the MC1R

  16. Visible Light Induces Melanogenesis in Human Skin through a Photoadaptive Response

    PubMed Central

    Randhawa, Manpreet; Seo, InSeok; Liebel, Frank; Southall, Michael D.; Kollias, Nikiforos; Ruvolo, Eduardo

    2015-01-01

    Visible light (400–700 nm) lies outside of the spectral range of what photobiologists define as deleterious radiation and as a result few studies have studied the effects of visible light range of wavelengths on skin. This oversight is important considering that during outdoors activities skin is exposed to the full solar spectrum, including visible light, and to multiple exposures at different times and doses. Although the contribution of the UV component of sunlight to skin damage has been established, few studies have examined the effects of non-UV solar radiation on skin physiology in terms of inflammation, and limited information is available regarding the role of visible light on pigmentation. The purpose of this study was to determine the effect of visible light on the pro-pigmentation pathways and melanin formation in skin. Exposure to visible light in ex-vivo and clinical studies demonstrated an induction of pigmentation in skin by visible light. Results showed that a single exposure to visible light induced very little pigmentation whereas multiple exposures with visible light resulted in darker and sustained pigmentation. These findings have potential implications on the management of photo-aggravated pigmentary disorders, the proper use of sunscreens, and the treatment of depigmented lesions. PMID:26121474

  17. Visible Light Induces Melanogenesis in Human Skin through a Photoadaptive Response.

    PubMed

    Randhawa, Manpreet; Seo, InSeok; Liebel, Frank; Southall, Michael D; Kollias, Nikiforos; Ruvolo, Eduardo

    2015-01-01

    Visible light (400-700 nm) lies outside of the spectral range of what photobiologists define as deleterious radiation and as a result few studies have studied the effects of visible light range of wavelengths on skin. This oversight is important considering that during outdoors activities skin is exposed to the full solar spectrum, including visible light, and to multiple exposures at different times and doses. Although the contribution of the UV component of sunlight to skin damage has been established, few studies have examined the effects of non-UV solar radiation on skin physiology in terms of inflammation, and limited information is available regarding the role of visible light on pigmentation. The purpose of this study was to determine the effect of visible light on the pro-pigmentation pathways and melanin formation in skin. Exposure to visible light in ex-vivo and clinical studies demonstrated an induction of pigmentation in skin by visible light. Results showed that a single exposure to visible light induced very little pigmentation whereas multiple exposures with visible light resulted in darker and sustained pigmentation. These findings have potential implications on the management of photo-aggravated pigmentary disorders, the proper use of sunscreens, and the treatment of depigmented lesions.

  18. Children's Color Perception in Relation to Habitat and Skin Color.

    ERIC Educational Resources Information Center

    Gaines, Rosslyn; Powell, Gloria J.

    1981-01-01

    Developmental color perception of 278 four- and eight-year-old Black and White children in three societies was examined in relation to the theories that proximity to the equator and that fundus pigmentation (as measured by skin color) reduce shortwave (blue-green) in comparison to long-wave perception. (Author/MP)

  19. Abnormal skin barrier in the etiopathogenesis of atopic dermatitis.

    PubMed

    Elias, Peter M; Schmuth, Matthias

    2009-07-01

    Prior studies revealed the key roles played by T-helper type 1 and type 2 (Th1/Th2) cell dysregulation, IgE production, mast cell hyperactivity, and dendritic cell signaling in the evolution of the chronic, pruritic, inflammatory dermatosis that characterizes atopic dermatitis (AD). Accordingly, current therapy has been largely directed toward ameliorating Th2-mediated inflammation and pruritus. This article reviews emerging evidence that the inflammation in AD results from inherited and acquired insults to the barrier, as well as the therapeutic implications of this new paradigm.

  20. Abnormal skin barrier in the etiopathogenesis of atopic dermatitis

    PubMed Central

    Elias, Peter M.; Schmuth, Matthias

    2010-01-01

    Purpose of review Many recent studies have revealed the key roles played by Th1/Th2 cell dysregulation, IgE production, mast cell hyperactivity, and dendritic cell signaling in the pathogenesis of atopic dermatitis. Accordingly, current therapy has been largely directed towards ameliorating Th2-mediated inflammation and/or pruritus. We will review here emerging evidence that the inflammation in atopic dermatitis results from inherited and acquired insults to the barrier and the therapeutic implications of this new paradigm. Recent findings Recent molecular genetic studies have shown a strong association between mutations in FILAGGRIN and atopic dermatitis, particularly in Northern Europeans. But additional acquired stressors to the barrier are required to initiate inflammation. Sustained hapten access through a defective barrier stimulates a Th1 → Th2 shift in immunophenotype, which in turn further aggravates the barrier. Secondary Staphylococcus aureus colonization not only amplifies inflammation but also further stresses the barrier in atopic dermatitis. Summary These results suggest a new ‘outside-to-inside, back to outside’ paradigm for the pathogenesis of atopic dermatitis. This new concept is providing impetus for the development of new categories of ‘barrier repair’ therapy. PMID:19550302

  1. DNA polymorphism and selection at the melanocortin-1 receptor gene in normally pigmented southern African individuals.

    PubMed

    John, Premila R; Makova, Kateryna; Li, Wen-Hsiung; Jenkins, Trefor; Ramsay, Michele

    2003-06-01

    Skin pigmentation is a polygenic multifactorial trait determined by the cumulative effects of multiple genetic variants and environmental factors. Melanocortin-1 receptor (MC1R) is one of the genes involved in pigmentation, and has been implicated in the red hair and pale skin phenotype in human Caucasoid individuals. The present study was undertaken to identify variation at the MC1R locus in normally pigmented individuals in two African populations, sub-Saharan Negroids (22 unrelated individuals) and the San (17 unrelated individuals). The study showed considerable MC1R gene sequence variation with the detection of eight synonymous and three nonsynonymous mutations. This is the first report of nonsynonymous mutations in African individuals in the MC1R gene: L99I was found in a single San individual, S47I was detected in a single Negroid individual, and F196L was detected in five Negroid individuals (5/44; 0.11). The functional significance of these mutations is not known. Three of the eight synonymous mutations found, L106L (CTG --> CTA), F300F (TTC --> TTT), and T314T (ACA --> ACG) (also known as A942G), have been reported previously. T314T was the only variant that showed a significant difference between the Negroid and San populations (0.477 and 0.059, respectively; P = 1.6 x 10(-5)). Its low frequency in the San may be the result of random genetic drift in a population of small size, or selection. Several tests of neutrality of the MC1R coding region in these and other African populations were significant, suggesting that purifying selection (functional constraint) had occurred at this gene locus in Africans. This demonstrates that although some nonsynonymous MC1R mutations are tolerated in individuals with dark skin, this gene has likely played a significant role in the maintenance of dark pigmentation in Africans and normal pigment variation in non-African populations.

  2. [The relativity of abnormity].

    PubMed

    Nilson, Annika

    2006-01-01

    In the late 19th century and in the beginning of the 20th century, mental diseases and abnormal behavior was considered to be a great danger to culture and society. "Degeneration" was the buzzword of the time, used and misused by artists and scientists alike. At the same time, some scientists saw abnormity as the key to unlock the mysteries of the ordinary mind. Naturalistic curiosity left Pandoras box open when religion declined in Darwins wake. Two swedish scientists, the physician Bror Gadelius (1862-1938) and his friend the philosopher Axel Herrlin (1870-1937), inspired by the French psychologist Theodule Ribots (1839-1916) "psychology without a soul", denied all fixed demarcation lines between abnormity and normality. All humans are natures creatures ruled by physiological laws, not ruled by God or convention. Even ordinary morality was considered to be an utterly backward explanation and guideline for complex human behavior. Different forms of therapy, not various kinds of penalties for wicked and disturbing behavior, are the now the solution for lots of people, "normal" as well as "abnormal". Psychiatry is expanding.

  3. Abnormalities of gonadal differentiation.

    PubMed

    Berkovitz, G D; Seeherunvong, T

    1998-04-01

    Gonadal differentiation involves a complex interplay of developmental pathways. The sex determining region Y (SRY) gene plays a key role in testis determination, but its interaction with other genes is less well understood. Abnormalities of gonadal differentiation result in a range of clinical problems. 46,XY complete gonadal dysgenesis is defined by an absence of testis determination. Subjects have female external genitalia and come to clinical attention because of delayed puberty. Individuals with 46,XY partial gonadal dysgenesis usually present in the newborn period for the valuation of ambiguous genitalia. Gonadal histology always shows an abnormality of seminiferous tubule formation. A diagnosis of 46,XY true hermaphroditism is made if the gonads contain well-formed testicular and ovarian elements. Despite the pivotal role of the SRY gene in testis development, mutations of SRY are unusual in subjects with a 46,XY karyotype and abnormal gonadal development. 46,XX maleness is defined by testis determination in an individual with a 46,XX karyotype. Most affected individuals have a phenotype similar to that of Klinefelter syndrome. In contrast, subjects with 46,XX true hermaphroditism usually present with ambiguous genitalia. The majority of subjects with 46,XX maleness have Y sequences including SRY in genomic DNA. However, only rare subjects with 46,XX true hermaphroditism have translocated sequences encoding SRY. Mosaicism and chimaerism involving the Y chromosome can also be associated with abnormal gonadal development. However, the vast majority of subjects with 45,X/46,XY mosaicism have normal testes and normal male external genitalia.

  4. Skin lumps

    MedlinePlus

    ... DM. Dermal and subcutaneous tumors. In: James WD, Berger TG, Elston DM, eds. Andrews' Diseases of the Skin: Clinical ... Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the ...

  5. Kaolin-based foliar reflectant and water deficit influence Malbec leaf and berry temperature, pigments, and photosynthesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of a kaolin-based foliar reflectant on traits of commercial interest in the red-skinned wine grape cultivar Malbec (Vitis vinifera L.) were evaluated over three growing seasons by measuring the surface temperatures of leaves and clusters, leaf-level assimilation, leaf and berry pigment c...

  6. High-throughput, high-content screening for novel pigmentation regulators using a keratinocyte/melanocyte co-culture system.

    PubMed

    Lee, Ju Hee; Chen, Hongxiang; Kolev, Vihren; Aull, Katherine H; Jung, Inhee; Wang, Jun; Miyamoto, Shoko; Hosoi, Junichi; Mandinova, Anna; Fisher, David E

    2014-02-01

    Skin pigmentation is a complex process including melanogenesis within melanocytes and melanin transfer to the keratinocytes. To develop a comprehensive screening method for novel pigmentation regulators, we used immortalized melanocytes and keratinocytes in co-culture to screen large numbers of compounds. High-throughput screening plates were subjected to digital automated microscopy to quantify the pigmentation via brightfield microscopy. Compounds with pigment suppression were secondarily tested for their effects on expression of microphthalmia transcription factor (MITF) and several pigment regulatory genes, and further validated in terms of non-toxicity to keratinocytes/melanocytes and dose-dependent activity. The results demonstrate a high-throughput, high-content screening approach, which is applicable to the analysis of large chemical libraries using a co-culture system. We identified candidate pigmentation inhibitors from 4000 screened compounds including zoxazolamine, 3-methoxycatechol and alpha-mangostin, which were also shown to modulate expression of MITF and several key pigmentation factors and are worthy of further evaluation for potential translation to clinical use.

  7. The common occurrence of epistasis in the determination of human pigmentation and its impact on DNA-based pigmentation phenotype prediction.

    PubMed

    Pośpiech, Ewelina; Wojas-Pelc, Anna; Walsh, Susan; Liu, Fan; Maeda, Hitoshi; Ishikawa, Takaki; Skowron, Małgorzata; Kayser, Manfred; Branicki, Wojciech

    2014-07-01

    The role of epistatic effects in the determination of complex traits is often underlined but its significance in the prediction of pigmentation phenotypes has not been evaluated so far. The prediction of pigmentation from genetic data can be useful in forensic science to describe the physical appearance of an unknown offender, victim, or missing person who cannot be identified via conventional DNA profiling. Available forensic DNA prediction systems enable the reliable prediction of several eye and hair colour categories. However, there is still space for improvement. Here we verified the association of 38 candidate DNA polymorphisms from 13 genes and explored the extent to which interactions between them may be involved in human pigmentation and their impact on forensic DNA prediction in particular. The model-building set included 718 Polish samples and the model-verification set included 307 independent Polish samples and additional 72 samples from Japan. In total, 29 significant SNP-SNP interactions were found with 5 of them showing an effect on phenotype prediction. For predicting green eye colour, interactions between HERC2 rs12913832 and OCA2 rs1800407 as well as TYRP1 rs1408799 raised the prediction accuracy expressed by AUC from 0.667 to 0.697 and increased the prediction sensitivity by >3%. Interaction between MC1R 'R' variants and VDR rs731236 increased the sensitivity for light skin by >1% and by almost 3% for dark skin colour prediction. Interactions between VDR rs1544410 and TYR rs1042602 as well as between MC1R 'R' variants and HERC2 rs12913832 provided an increase in red/non-red hair prediction accuracy from an AUC of 0.902-0.930. Our results thus underline epistasis as a common phenomenon in human pigmentation genetics and demonstrate that considering SNP-SNP interactions in forensic DNA phenotyping has little impact on eye, hair and skin colour prediction.

  8. Role of Micronutrients in Skin Health and Function

    PubMed Central

    Park, Kyungho

    2015-01-01

    Skin is the first line of defense for protecting our bodies against external perturbations, including ultraviolet (UV) irradiation, mechanical/chemical stress, and bacterial infection. Nutrition is one of many factors required for the maintenance of overall skin health. An impaired nutritional status alters the structural integrity and biological function of skin, resulting in an abnormal skin barrier. In particular, the importance of micronutrients (such as certain vitamins and minerals) for skin health has been highlighted in cell culture, animal, and clinical studies. These micronutrients are employed not only as active compounds in therapeutic agents for treating certain skin diseases, but also as ingredients in cosmetic products. Here, the author describes the barrier function of the skin and the general nutritional requirements for skin health. The goal of this review is to discuss the potential roles and current knowledge of selected micronutrients in skin health and function. PMID:25995818

  9. Role of micronutrients in skin health and function.

    PubMed

    Park, Kyungho

    2015-05-01

    Skin is the first line of defense for protecting our bodies against external perturbations, including ultraviolet (UV) irradiation, mechanical/chemical stress, and bacterial infection. Nutrition is one of many factors required for the maintenance of overall skin health. An impaired nutritional status alters the structural integrity and biological function of skin, resulting in an abnormal skin barrier. In particular, the importance of micronutrients (such as certain vitamins and minerals) for skin health has been highlighted in cell culture, animal, and clinical studies. These micronutrients are employed not only as active compounds in therapeutic agents for treating certain skin diseases, but also as ingredients in cosmetic products. Here, the author describes the barrier function of the skin and the general nutritional requirements for skin health. The goal of this review is to discuss the potential roles and current knowledge of selected micronutrients in skin health and function.

  10. Quantitative skin color measurements in acanthosis nigricans patients: colorimetry and diffuse reflectance spectroscopy.

    PubMed

    Pattamadilok, Bensachee; Devpura, Suneetha; Syed, Zain U; Agbai, Oma N; Vemulapalli, Pranita; Henderson, Marsha; Rehse, Steven J; Mahmoud, Bassel H; Lim, Henry W; Naik, Ratna; Hamzavi, Iltefat H

    2012-08-01

    Tristimulus colorimetry and diffuse reflectance spectroscopy (DRS) are white-light skin reflectance techniques used to measure the intensity of skin pigmentation. The tristimulus colorimeter is an instrument that measures a perceived color and the DRS instrument measures biological chromophores of the skin, including oxy- and deoxyhemoglobin, melanin and scattering. Data gathered from these tools can be used to understand morphological changes induced in skin chromophores due to conditions of the skin or their treatments. The purpose of this study was to evaluate the use of these two instruments in color measurements of acanthosis nigricans (AN) lesions. Eight patients with hyperinsulinemia and clinically diagnosable AN were seen monthly. Skin pigmentation was measured at three sites: the inner forearm, the medial aspect of the posterior neck, and anterior neck unaffected by AN. Of the three, measured tristimulus L*a*b* color parameters, the luminosity parameter L* was found to most reliably distinguish lesion from normally pigmented skin. The DRS instrument was able to characterize a lesion on the basis of the calculated melanin concentration, though melanin is a weak indicator of skin change and not a reliable measure to be used independently. Calculated oxyhemoglobin and deoxyhemoglobin concentrations were not found to be reliable indicators of AN. Tristimulus colorimetry may provide reliable methods for respectively quantifying and characterizing the objective color change in AN, while DRS may be useful in characterizing changes in skin melanin content associated with this skin condition.

  11. Thin Layer Chromatography (TLC) of Chlorophyll Pigments.

    ERIC Educational Resources Information Center

    Foote, Jerry

    1984-01-01

    Background information, list of materials needed, procedures used, and discussion of typical results are provided for an experiment on the thin layer chromatography of chlorophyll pigments. The experiment works well in high school, since the chemicals used are the same as those used in paper chromatography of plant pigments. (JN)

  12. Natural and sun-induced aging of human skin.

    PubMed

    Rittié, Laure; Fisher, Gary J

    2015-01-05

    With worldwide expansion of the aging population, research on age-related pathologies is receiving growing interest. In this review, we discuss current knowledge regarding the decline of skin structure and function induced by the passage of time (chronological aging) and chronic exposure to solar UV irradiation (photoaging). Nearly every aspect of skin biology is affected by aging. The self-renewing capability of the epidermis, which provides vital barrier function, is diminished with age. Vital thermoregulation function of eccrine sweat glands is also altered with age. The dermal collagenous extracellular matrix, which comprises the bulk of skin and confers strength and resiliency, undergoes gradual fragmentation, which deleteriously impacts skin mechanical properties and dermal cell functions. Aging also affects wound repair, pigmentation, innervation, immunity, vasculature, and subcutaneous fat homeostasis. Altogether, age-related alterations of skin lead to age-related skin fragility and diseases.

  13. Natural and Sun-Induced Aging of Human Skin

    PubMed Central

    Rittié, Laure; Fisher, Gary J.

    2015-01-01

    With worldwide expansion of the aging population, research on age-related pathologies is receiving growing interest. In this review, we discuss current knowledge regarding the decline of skin structure and function induced by the passage of time (chronological aging) and chronic exposure to solar UV irradiation (photoaging). Nearly every aspect of skin biology is affected by aging. The self-renewing capability of the epidermis, which provides vital barrier function, is diminished with age. Vital thermoregulation function of eccrine sweat glands is also altered with age. The dermal collagenous extracellular matrix, which comprises the bulk of skin and confers strength and resiliency, undergoes gradual fragmentation, which deleteriously impacts skin mechanical properties and dermal cell functions. Aging also affects wound repair, pigmentation, innervation, immunity, vasculature, and subcutaneous fat homeostasis. Altogether, age-related alterations of skin lead to age-related skin fragility and diseases. PMID:25561721

  14. Water content and structure in malignant and benign skin tumours

    NASA Astrophysics Data System (ADS)

    Gniadecka, M.; Nielsen, O. F.; Wulf, H. C.

    2003-12-01

    Analysis of the low frequency region of Raman spectra enables determination of water structure. It has been previously demonstrated by various techniques that water content and possibly also the water structure is altered in some malignant tumours. To further elucidate possible change in water structure in tumours we performed NIR FT Raman spectroscopy on biopsies from selected benign and malignant skin tumours (benign: seborrheic keratosis, pigmented nevi; malignant: malignant melanoma, basal cell carcinoma). We did not observe any differences in water content between malignant and benign skin tumours with an exception of seborrheic keratosis, in which the water content was decreased. Increase in the tetrahedral (free) water was found in malignant skin tumours and sun-damaged skin relative to normal young skin and benign skin tumours. This finding may add to the understanding of molecular alterations in cancer.

  15. Failure of flat warts to recur in electrosurgically altered skin.

    PubMed

    Berman, A

    1978-12-01

    Two men with recurring flat warts in the beard area have been observed for five and ten years, respectively. Both have depigmented patches at sites where flat warts had been removed by electrosurgical destruction. Crops of new warts appear periodically. These develop always on the normally pigmented skin and have never been found in the leukodermic areas. Flat warts have been observed repeatedly at the margin of depigmented and normal skin; these invariably enlarge toward the normal skin and never encroach on leukodermic skin. The failure of flat warts to develop in electrosurgically treated skin, if substantiated, would indicate that local tissue factors influence resistance to development of flat warts. Perhaps this phenomenon is similar to that reported in Darier's disease, where partial-thickness excision of involved skin has resulted in resistance to recurrent disease.

  16. Coloration reflects skin pterin concentration in a red-tailed lizard.

    PubMed

    Cuervo, José J; Belliure, Josabel; Negro, Juan J

    2016-03-01

    When integumentary tissue pigments are contained in chromatophores, tissue color might not depend exclusively on the amount of pigment. Whether coloration does or does not reflect pigment concentration may be very significant for intraspecific communication, for example when pigment concentration provides fitness-related information. We studied the pigment responsible for the orange/red ventral tail coloring in a lacertid lizard species (Acanthodactylus erythrurus), and whether the color was related to skin pigment concentration. The pigment was identified as a pterin, a higher concentration of which resulted in darker, more red-saturated, redder (less orange) ventral tail skin color. The dorsal tail integument, even though it appears mostly gray to the naked eye, also contained pterins, and furthermore, the dorsal and ventral pterin concentrations were positively correlated. A possible explanation for these results is that pterins accumulate in the skin of the whole tail, even if only needed in the ventral part, but are concealed in the dorsal part. In this way, ventral orange/red coloration would accurately reflect pterin concentration, which provides the basis for a signaling function, while dorsal coloration would become less conspicuous as an anti-predatory mechanism.

  17. Bilateral pigmented villonodular synovitis of the knee

    PubMed Central

    Shah, Samir H.; Porrino, Jack A.; Green, John R.; Chew, Felix S.

    2015-01-01

    Pigmented villonodular synovitis is a disorder resulting in a villous, nodular, or villonodular proliferation of the synovium, with pigmentation related to the presence of hemosiderin. These lesions are almost exclusively benign with rare reports of malignancy. Pigmented villonodular synovitis can occur in a variety of joints and at any age but most often occurs within the knee in the young adult. Pigmented villonodular synovitis is a rare disease entity, and bilateral synchronous or metachronous involvement of a joint is even more uncommon, with few reports previously described in the literature. We present a case of pigmented villonodular synovitis involving both the right and left knee in the same patient, with radiographic imaging, magnetic resonance imaging, photograph and video intraoperative imaging, and pathologic correlation. PMID:26649121

  18. Developing fungal pigments for "painting" vascular plants.

    PubMed

    Robinson, Sara C

    2012-02-01

    The use of fungal pigments as color additives to wood as a method to increase forest revenue is a relatively new, but quickly developing field. Sugar maple (Acer saccharum) is currently the primary utilized hardwood for spalting and appears to be the best suited North American hardwood for such purposes. The combination of Trametes versicolor and Bjerkandera adusta has been identified in several instances as a strong fungal pairing for zone line production; however, Xylaria polymorpha is capable of creating zone lines without the antagonism of a secondary fungus. Few fungal pigments have been developed for reliable use; Scytalidium cuboideum is capable of producing a penetrating pink/red stain, as well as a blue pigment after extended incubation, and Chlorociboria sp. produces a blue/green pigment if grown on aspen (Populus tremuloides). Several opportunities exist for stimulation of fungal pigments including the use of copper sulfate and changes in wood pH.

  19. Organic pigments in plastics can cause allergic contact dermatitis.

    PubMed

    Jolanki, R; Kanerva, L; Estlander, T

    1987-01-01

    A short review on organic pigments in plastics as a cause of allergic contact dermatitis is presented. Previously, organic pigments have been reported as provoking allergic pigmented contact dermatitis when used in cosmetics. Here we present the case of a patient who developed allergic contact dermatitis from an organic pigment (Irgalite Orange F2G) in a plastic glove. This shows that organic pigments in plastics can also cause allergic contact dermatitis. The potential sensitizing capacity of organic pigments should be noted.

  20. Susceptibility loci for pigmentation and melanoma in relation to Parkinson's disease.

    PubMed

    Dong, Jing; Gao, Jianjun; Nalls, Michael; Gao, Xiang; Huang, Xuemei; Han, Jiali; Singleton, Andrew B; Chen, Honglei

    2014-06-01

    Growing evidence suggests that Parkinson's disease (PD) patients have a lower risk for most types of cancer except for melanoma, which has a modest positive association with PD. Pigmentation genes have been hypothesized to contribute to this association. We therefore examined whether genetic susceptibility loci for pigmentation or melanoma was associated with PD risk in 2 large independent datasets. In the Parkinson's Genes and Environment (PAGE) study, we examined 11 single-nucleotide polymorphisms (SNPs) identified from previous genome-wide association studies (GWAS) of pigmentation or melanoma in relation to PD among 808 PD cases and 1623 controls; furthermore, we also examined the colors of hair, eye, or skin and melanoma in relation to PD. In the International Parkinson's Disease Genomic Consortium (IPDGC), we examined a broader selection of 360 pigmentation or melanoma GWAS SNPs in relation to PD among 5,333 PD cases and 12,019 controls. All participants were non-Hispanic Whites. As expected, in the PAGE study, most SNPs were associated with 1 or more pigmentation phenotypes. However, neither these SNPs nor pigmentation phenotypes were associated with PD risk after Bonferroni correction with the exception of rs4911414 at the ASIP gene (p = .001). A total of 18 PD cases (2.2%) and 26 controls (1.6%) had a diagnosis of melanoma with an odds ratio of 1.3 (95% confidence interval: 0.7-2.4). In the IPDGC analysis, none of the 360 SNPs, including rs4911414, were associated with PD risk after adjusting for multiple comparisons. In conclusion, we did not find significant associations between GWAS SNPs of pigmentation or melanoma and the risk for PD.

  1. Susceptibility Loci for Pigmentation and Melanoma in Relation to Parkinson’s disease

    PubMed Central

    Nalls, Michael; Gao, Xiang; Huang, Xuemei; Han, Jiali; Singleton, Andrew B.; Chen, Honglei

    2014-01-01

    Growing evidence suggests that Parkinson’s disease (PD) patients have a lower risk for most types of cancer except for melanoma, which has a modest positive association with PD. Pigmentation genes has been hypothesized to contribute to this association. We therefore examined whether genetic susceptibility loci for pigmentation or melanoma were associated with PD risk in two large independent datasets. In the Parkinson’s Genes and Environment (PAGE) Study, we examined 11 SNPs identified from previous GWAS studies of pigmentation or melanoma in relation to PD among 808 PD cases and 1,623 controls; further, we also examined the colors of hair, eye, or skin, and melanoma in relation to PD. In the International Parkinson’s Disease Genomic Consortium (IPDGC), we examined a broader selection of 360 pigmentation or melanoma GWAS SNPs in relation to PD among 5,333 PD cases and 12,019 controls. All participants were non-Hispanic Whites. As expected, in the PAGE study, most SNPs were associated with one or more pigmentation phenotypes. However, neither these SNPs nor pigmentation phenotypes were associated with PD risk after Bonferroni correction with the exception of rs4911414 at the ASIP gene (P=0.001). A total of 18 PD cases (2.2%) and 26 controls (1.6%) had a diagnosis of melanoma with an odds ratio of 1.3 (95% confidence interval: 0.7-2.4). In the IPDGC analysis, none of the 360 SNPs, including rs4911414, were associated with PD risk after adjusting for multiple comparisons. In conclusion, we did not find significant associations between GWAS SNPs of pigmentation or melanoma and the risk for PD. PMID:24439955

  2. [Association of skin problems with coat colour and white markings in three-year-old horses of the Franches-Montagnes breed].

    PubMed

    Federici, M; Gerber, V; Doherr, M G; Klopfenstein, S; Burger, D

    2015-07-01

    In the last 30 years the amount of white markings in the population of Franches-Montagnes horses (FM) has more than doubled which has led to some controversy, particularly in respect to the health of the horses. The objective of this study was to investigate if the coat colour and white markings have an impact on selected skin diseases and hoof horn abnormalities. To this purpose 974 three-year-old FM were subjected to a clinical examination during the field and station tests organized by the FM breeding association. In 16.9% of the horses, one or several equine sarcoids were detected, 15.2% of the horses showed clinical signs of pastern dermatitis, 1.1% of insect bite hypersensitivity and 18.0% of dermatitis of other aetiology. Abnormalities of the hoof horn were found in 20.1% of the horses. The prevalence of pastern dermatitis was 2.6 times higher in legs with white markings than in legs with pigmented skin (p <0.0001). The probability ofsuffering from sunburn and hoof horn of lesser quality was increased in animals with an elevated white marking index (WAI; p = 0.022 and p = 0.038), on the other hand, horses with sarcoids had a significantly lower WAI than sound horses (p = 0.038). Our study shows that FM horses with more pronounced white markings have an increased risk to suffer from pastern dermatitis, sunburns and hoof horn abnormalities. The coat colour was not associated with skin diseases.

  3. Melanocytes in the Skin – Comparative Whole Transcriptome Analysis of Main Skin Cell Types

    PubMed Central

    Reemann, Paula; Reimann, Ene; Ilmjärv, Sten; Porosaar, Orm; Silm, Helgi; Jaks, Viljar; Vasar, Eero; Kingo, Külli; Kõks, Sulev

    2014-01-01

    Melanocytes possess several functions besides a role in pigment synthesis, but detailed characteristics of the cells are still unclear. We used whole transcriptome sequencing (RNA-Seq) to assess differential gene expression of cultivated normal human melanocytes with respect to keratinocytes, fibroblasts and whole skin. The present results reveal cultivated melanocytes as highly proliferative cells with possible stem cell-like properties. The enhanced readiness to regenerate makes melanocytes the most vulnerable cells in the skin and explains their high risk of developing into malignant melanoma. PMID:25545474

  4. Melanocytes in the skin--comparative whole transcriptome analysis of main skin cell types.

    PubMed

    Reemann, Paula; Reimann, Ene; Ilmjärv, Sten; Porosaar, Orm; Silm, Helgi; Jaks, Viljar; Vasar, Eero; Kingo, Külli; Kõks, Sulev

    2014-01-01

    Melanocytes possess several functions besides a role in pigment synthesis, but detailed characteristics of the cells are still unclear. We used whole transcriptome sequencing (RNA-Seq) to assess differential gene expression of cultivated normal human melanocytes with respect to keratinocytes, fibroblasts and whole skin. The present results reveal cultivated melanocytes as highly proliferative cells with possible stem cell-like properties. The enhanced readiness to regenerate makes melanocytes the most vulnerable cells in the skin and explains their high risk of developing into malignant melanoma.

  5. Anthocyanins. Plant pigments and beyond.

    PubMed

    Santos-Buelga, Celestino; Mateus, Nuno; De Freitas, Victor

    2014-07-23

    Anthocyanins are plant pigments widespread in nature. They play relevant roles in plant propagation and ecophysiology and plant defense mechanisms and are responsible for the color of fruits and vegetables. A large number of novel anthocyanin structures have been identified, including new families such as pyranoanthocyanins or anthocyanin oligomers; their biosynthesis pathways have been elucidated, and new plants with "a la carte" colors have been created by genetic engineering. Furthermore, evidence about their benefits in human health has accumulated, and processes of anthocyanin absorption and biotransformation in the human organism have started to be ascertained. These advances in anthocyanin research were revised in the Seventh International Workshop on Anthocyanins that took place in Porto (Portugal) on September 9-11, 2013. Some selected papers are collected in this special issue, where aspects such as anthocyanin accumulation in plants, relationship with color expression, stability in plants and food, and bioavailability or biological activity are revised.

  6. Structure of plant bile pigments

    SciTech Connect

    Schoenleber, R.W.

    1983-12-01

    Selective peptide cleavage has provided a general procedure for the study of the structure, including stereochemistry, of plant bile pigments. The information derived from the synthesis and spectral analysis of a series of 2,3-dihydrodioxobilins allows the determination of the trans relative stereochemistry for ring A of the ..beta../sub 1/-phycocyanobilin from C-phycocyanin as well as for ring A of phytochrome. A complete structure proof of the five phycoerythrobilins attached to the ..cap alpha.. and ..beta.. subunits of B-phycoerythrin is described. One of these tetrapyrroles is doubly-peptide linked to a single peptide chain through two thioethers at the C-3' and C-18' positions. The four remaining phycoerythrobilins are singly-linked to the protein through thioethers at the C-3' position and all possess the probable stereochemistry C-2(R), C-3(R), C-3'(R), and C-16(R).

  7. Heritable bovine fetal abnormalities.

    PubMed

    Whitlock, B K; Kaiser, L; Maxwell, H S

    2008-08-01

    The etiologies for congenital bovine fetal anomalies can be divided into heritable, toxic, nutritional, and infectious categories. Although uncommon in most herds, inherited congenital anomalies are probably present in all breeds of cattle and propagated as a result of specific trait selection that inadvertently results in propagation of the defect. In some herds, the occurrence of inherited anomalies has become frequent, and economically important. Anomalous traits can affect animals in a range of ways, some being lethal or requiring euthanasia on humane grounds, others altering structure, function, or performance of affected animals. Veterinary practitioners should be aware of the potential for inherited defects, and be prepared to investigate and report animals exhibiting abnormal characteristics. This review will discuss the morphologic characteristics, mode of inheritance, breeding lines affected, and the availability of genetic testing for selected heritable bovine fetal abnormalities.

  8. Liver abnormalities in pregnancy.

    PubMed

    Than, Nwe Ni; Neuberger, James

    2013-08-01

    Abnormalities of liver function (notably rise in alkaline phosphatase and fall in serum albumin) are common in normal pregnancy, whereas rise in serum bilirubin and aminotransferase suggest either exacerbation of underlying pre-existing liver disease, liver disease related to pregnancy or liver disease unrelated to pregnancy. Pregnant women appear to have a worse outcome when infected with Hepatitis E virus. Liver diseases associated with pregnancy include abnormalities associated hyperemesis gravidarum, acute fatty liver disease, pre-eclampsia, cholestasis of pregnancy and HELLP syndrome. Prompt investigation and diagnosis is important in ensuring a successful maternal and foetal outcome. In general, prompt delivery is the treatment of choice for acute fatty liver, pre-eclampsia and HELLP syndrome and ursodeoxycholic acid is used for cholestasis of pregnancy although it is not licenced for this indication.

  9. Skin Cancer Foundation

    MedlinePlus

    ... Host a Fundraising Event | About Us | Store The Skin Cancer Foundation The Skin Cancer Foundation is the ... Handbook A "Sunscreen Gene"? Skin Cancer Facts & Statistics Skin Cancer Treatment Glossary Information on medications and procedures ...

  10. In vivo pump-probe microscopy of melanoma and pigmented lesions

    NASA Astrophysics Data System (ADS)

    Wilson, Jesse W.; Degan, Simone; Mitropoulos, Tanya; Selim, M. Angelica; Zhang, Jennifer Y.; Warren, Warren S.

    2012-03-01

    A growing number of dermatologists and pathologists are concerned that the rapidly rising incidence of melanoma reflects not a true 'epidemic' but an increasing tendency to overdiagnose pigmented lesions. Addressing this problem requires both a better understanding of early-stage melanoma and new diagnostic criteria based on more than just cellular morphology and architecture. Here we present a method for in-vivo optical microscopy that utilizes pump-probe spectroscopy to image the distribution of the two forms of melanin in skin: eumelanin and pheomelanin. Images are acquired in a scanning microscope with a sensitive modulation transfer technique by analyzing back-scattered probe light with a lock-in amplifier. Early-stage melanoma is studied in a human skin xenografted mouse model. Individual melanocytes have been observed, in addition to pigmented keratinocytes. Combining the pump-probe images simultaneously with other noninvasive laser microscopy methods (confocal reflectance, multiphoton autofluorescence, and second harmonic generation) allows visualization of the skin architecture, framing the functional pump-probe image in the context of the surrounding tissue morphology. It is found that pump-probe images of melanin can be acquired with low peak intensities, enabling wide field-of-view pigmentation surveys. Finally, we investigate the diagnostic potential of the additional chemical information available from pump-probe microscopy.

  11. Morphological abnormalities in elasmobranchs.

    PubMed

    Moore, A B M

    2015-08-01

    A total of 10 abnormal free-swimming (i.e., post-birth) elasmobranchs are reported from The (Persian-Arabian) Gulf, encompassing five species and including deformed heads, snouts, caudal fins and claspers. The complete absence of pelvic fins in a milk shark Rhizoprionodon acutus may be the first record in any elasmobranch. Possible causes, including the extreme environmental conditions and the high level of anthropogenic pollution particular to The Gulf, are briefly discussed.

  12. Anatomical Abnormalities in Autism?

    PubMed

    Haar, Shlomi; Berman, Sigal; Behrmann, Marlene; Dinstein, Ilan

    2016-04-01

    Substantial controversy exists regarding the presence and significance of anatomical abnormalities in autism spectrum disorders (ASD). The release of the Autism Brain Imaging Data Exchange (∼1000 participants, age 6-65 years) offers an unprecedented opportunity to conduct large-scale comparisons of anatomical MRI scans across groups and to resolve many of the outstanding questions. Comprehensive univariate analyses using volumetric, thickness, and surface area measures of over 180 anatomically defined brain areas, revealed significantly larger ventricular volumes, smaller corpus callosum volume (central segment only), and several cortical areas with increased thickness in the ASD group. Previously reported anatomical abnormalities in ASD including larger intracranial volumes, smaller cerebellar volumes, and larger amygdala volumes were not substantiated by the current study. In addition, multivariate classification analyses yielded modest decoding accuracies of individuals' group identity (<60%), suggesting that the examined anatomical measures are of limited diagnostic utility for ASD. While anatomical abnormalities may be present in distinct subgroups of ASD individuals, the current findings show that many previously reported anatomical measures are likely to be of low clinical and scientific significance for understanding ASD neuropathology as a whole in individuals 6-35 years old.

  13. Possibility of increasing the efficiency of laser-induced tattoo removal by optical skin clearing

    NASA Astrophysics Data System (ADS)

    Genina, E. A.; Bashkatov, A. N.; Tuchin, V. V.; Altshuler, G. B.; Yaroslavskii, I. V.

    2008-06-01

    The possibility of selective laser photothermolysis improvement for the removal of tattoo pigments due to the optical clearing of human skin is investigated. It is shown experimentally that the optical skin clearing increases the tattoo image contrast. Computer Monte Carlo simulations show that by decreasing the laser beam scattering in upper skin layers, it is possible to reduce the radiation power required for tattoo removal by 30%—40% and, therefore, to increase the the photothermolysis efficiency.

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

    PubMed

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

    2015-07-01

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

  15. 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.

  16. [Effect of long-wave ultraviolet light (UV-A) and medium-wave ultraviolet rays (UV-B) on human skin. Critical comparison].

    PubMed

    Raab, W

    1980-04-15

    When discussing the effects of ultraviolet radiation on human skin, one should carefully distinguish between the long wave ultraviolet light (UV-A) and the short wave radiations (UV-B and UV-C). Ultraviolet A induces immediate pigmentation but, if high energies are applied, a permanent pigmentation is elicited. This type of ultraviolet A-induced pigmentation has been called "spontaneous" pigmentation as no erythematous reaction is necessary to induce or accelerate melanine formation. Ultraviolet B provokes erythema and consecutive pigmentation. Upon chronic exposure, ultraviolet B causes the wellknown actinic damage of the skin and even provokes carcinoma. With exposures to the sunlight (global radiation), one should be most careful. The public must be informed extensively about the dangers of excessive sunbaths. The use of artificial "suns" with spectra between 260 and 400 nm is limited as it may cause the same type of damage as the global radiation. An exact schedule for use of artificial lamps is strongly recommended. After one cycle of exposures, an interruption is necessary until the next cycle of irradiations may start. Upon continual use for tanning of the skin, artificial lamps may provoke irreversible damage of the skin. Radiation sources with emission spectra of wavelengths between 315 and 400 nm exclusively are well suited for the induction of skin pigmentation (cosmetic use). Potent radiation such as UVASUN systems provoke a "pleasant" permanent pigmentation after exposures for less than one hour. The use of ultraviolet A (UV-A) does not carry any risk for the human skin.

  17. Ultraviolet radiation directly induces pigment production by cultured human melanocytes

    SciTech Connect

    Friedmann, P.S.; Gilchrest, B.A.

    1987-10-01

    In humans the major stimulus for cutaneous pigmentation is ultraviolet radiation (UVR). Little is known about the mechanism underlying this response, in part because of the complexity of interactions in whole epidermis. Using a recently developed culture system, human melanocytes were exposed daily to a physiologic range of UVR doses from a solar simulator. Responses were determined 24 hours after the last exposure. There was a dose-related increase in melanin content per cell and uptake of /sup 14/C-DOPA, accompanied by growth inhibition. Cells from donors of different racial origin gave proportionately similar increases in melanin, although there were approximately tenfold differences in basal values. Light and electron microscopy revealed UVR-stimulated increases in dendricity as well as melanosome number and degree of melanization, analogous to the well-recognized melanocyte changes following sun exposure of intact skin. Similar responses were seen with Cloudman S91 melanoma cells, although this murine cell line required lower UVR dosages and fewer exposures for maximal stimulation. These data establish that UVR is capable of directly stimulating melanogenesis. Because cyclic AMP elevation has been associated in some settings with increased pigment production by cultured melanocytes, preliminary experiments were conducted to see if the effects of UVR were mediated by cAMP. Both alpha-MSH and isobutylmethylxanthine (IBMX), as positive controls, caused a fourfold increase in cAMP level in human melanocytes and/or S91 cells, but following a dose of UVR sufficient to stimulate pigment production there was no change in cAMP level up to 4 hours after exposure. Thus, it appears that the UVR-induced melanogenesis is mediated by cAMP-independent mechanisms.

  18. Abnormal pressures as hydrodynamic phenomena

    USGS Publications Warehouse

    Neuzil, C.E.

    1995-01-01

    So-called abnormal pressures, subsurface fluid pressures significantly higher or lower than hydrostatic, have excited speculation about their origin since subsurface exploration first encountered them. Two distinct conceptual models for abnormal pressures have gained currency among earth scientists. The static model sees abnormal pressures generally as relict features preserved by a virtual absence of fluid flow over geologic time. The hydrodynamic model instead envisions abnormal pressures as phenomena in which flow usually plays an important role. This paper develops the theoretical framework for abnormal pressures as hydrodynamic phenomena, shows that it explains the manifold occurrences of abnormal pressures, and examines the implications of this approach. -from Author

  19. Cutaneous skin tag

    MedlinePlus

    Skin tag; Acrochordon; Fibroepithelial polyp ... have diabetes. They are thought to occur from skin rubbing against skin. ... The tag sticks out of the skin and may have a short, narrow stalk connecting it to the surface of the skin. Some skin tags are as long as ...

  20. [Molecular abnormalities in lymphomas].

    PubMed

    Delsol, G

    2010-11-01

    Numerous molecular abnormalities have been described in lymphomas. They are of diagnostic and prognostic value and are taken into account for the WHO classification of these tumors. They also shed some light on the underlying molecular mechanisms involved in lymphomas. Overall, four types of molecular abnormalities are involved: mutations, translocations, amplifications and deletions of tumor suppressor genes. Several techniques are available to detect these molecular anomalies: conventional cytogenetic analysis, multicolor FISH, CGH array or gene expression profiling using DNA microarrays. In some lymphomas, genetic abnormalities are responsible for the expression of an abnormal protein (e.g. tyrosine-kinase, transcription factor) detectable by immunohistochemistry. In the present review, molecular abnormalities observed in the most frequent B, T or NK cell lymphomas are discussed. In the broad spectrum of diffuse large B-cell lymphomas microarray analysis shows mostly two subgroups of tumors, one with gene expression signature corresponding to germinal center B-cell-like (GCB: CD10+, BCL6 [B-Cell Lymphoma 6]+, centerine+, MUM1-) and a subgroup expressing an activated B-cell-like signature (ABC: CD10-, BCL6-, centerine-, MUM1+). Among other B-cell lymphomas with well characterized molecular abnormalies are follicular lymphoma (BCL2 deregulation), MALT lymphoma (Mucosa Associated Lymphoid Tissue) [API2-MALT1 (mucosa-associated-lymphoid-tissue-lymphoma-translocation-gene1) fusion protein or deregulation BCL10, MALT1, FOXP1. MALT1 transcription factors], mantle cell lymphoma (cycline D1 [CCND1] overexpression) and Burkitt lymphoma (c-Myc expression). Except for ALK (anaplastic lymphoma kinase)-positive anaplastic large cell lymphoma, well characterized molecular anomalies are rare in lymphomas developed from T or NK cells. Peripheral T cell lymphomas not otherwise specified are a heterogeneous group of tumors with frequent but not recurrent molecular abnormalities

  1. Basis for the gain and subsequent dilution of epidermal pigmentation during human evolution: The barrier and metabolic conservation hypotheses revisited.

    PubMed

    Elias, Peter M; Williams, Mary L

    2016-10-01

    The evolution of human skin pigmentation must address both the initial evolution of intense epidermal pigmentation in hominins, and its subsequent dilution in modern humans. While many authorities believe that epidermal pigmentation evolved to protect against either ultraviolet B (UV-B) irradiation-induced mutagenesis or folic acid photolysis, we hypothesize that pigmentation augmented the epidermal barriers by shifting the UV-B dose-response curve from toxic to beneficial. Whereas erythemogenic UV-B doses produce apoptosis and cell death, suberythemogenic doses benefit permeability and antimicrobial function. Heavily melanized melanocytes acidify the outer epidermis and emit paracrine signals that augment barrier competence. Modern humans, residing in the cooler, wetter climes of south-central Europe and Asia, initially retained substantial pigmentation. While their outdoor lifestyles still permitted sufficient cutaneous vitamin D3 (VD3) synthesis, their marginal nutritional status, coupled with cold-induced caloric needs, selected for moderate pigment reductions that diverted limited nutritional resources towards more urgent priorities (=metabolic conservation). The further pigment-dilution that evolved as humans reached north-central Europe (i.e., northern France, Germany), likely facilitated cutaneous VD3 synthesis, while also supporting ongoing, nutritional requirements. But at still higher European latitudes where little UV-B breaches the atmosphere (i.e., present-day UK, Scandinavia, Baltic States), pigment dilution alone could not suffice. There, other nonpigment-related mutations evolved to facilitate VD3 production; for example, in the epidermal protein, filaggrin, resulting in reduced levels of its distal metabolite, trans-urocanic acid, a potent UV-B chromophore. Thus, changes in human pigmentation reflect a complex interplay between latitude, climate, diet, lifestyle, and shifting metabolic priorities.

  2. Pigmented dermatofibrosarcoma protuberans with prominent meningothelial-like whorls.

    PubMed

    Wang, Jian; Yang, Wentao

    2008-10-01

    Dermatofibrosarcoma protuberans (DFSP) is a locally aggressive skin tumor. In addition to the conventional type, several morphologic variants have been described. Recognition of these uncommon variants will facilitate the diagnosis. We report herein a peculiar case of pigmented DFSP (Bednar tumor) with prominent meningothelial-like whorls, a distinctive pattern that has not been described previously in DFSP. The tumor occurred in a 40-year-old man who presented with a slowly growing mass on his left shoulder. The overall histological features were consistent with Bednar tumor. However, unexpected numerous meningothelial-like whorls were found in some areas of the tumor. Like the tumor cells in typical areas of Bednar tumor these meningothelial-like whorls were also positive for CD34 but negative for epithelial membrane antigen and S100 protein. The meningothelial-like whorls in Bednar tumor represent an eccentric arrangement of the tumor cells. We propose the term 'pigmented DFSP with prominent meningothelial-like whorls' to highlight the distinctive pattern of this novel DFSP variant.

  3. Assessing human skin with diffuse reflectance spectroscopy and colorimetry

    NASA Astrophysics Data System (ADS)

    Seo, InSeok; Liu, Yang; Bargo, Paulo R.; Kollias, Nikiforos

    2012-02-01

    Colorimetry has been used as an objective measure of perceived skin color by human eye to document and score physiological responses of the skin from external insults. CIE color space values (L*, a* and b*) are the most commonly used parameters to correlate visually perceived color attributes such as L* for pigment, a* for erythema, and b* for sallowness of the skin. In this study, we investigated the relation of Lab color scale to the amount of major skin chromophores (oxy-, deoxyhemoglobin and melanin) calculated from diffuse reflectance spectroscopy. Thirty two healthy human subjects with ages from 20 to 70 years old, skin types I-VI, were recruited for the study. DRS and colorimetry measurements were taken from the left and right cheeks, and on the right upper inner arm. The melanin content calculated from 630-700 nm range of DRS measurements was shown to correlate with the lightness of skin (L*) for most skin types. For subjects with medium-to-light complexion, melanin measured at the blue part spectrum and hemoglobin interfered on the relation of lightness of the skin color to the melanin content. The sallowness of the skin that is quantified by the melanin contribution at the blue part spectrum of DRS was found to be related to b* scale. This study demonstrates the importance of documenting skin color by assessing individual skin chromophores with diffuse reflectance spectroscopy, in comparison to colorimetry assessment.

  4. Effects of air pollution on the skin: A review.

    PubMed

    Puri, Poonam; Nandar, Shashi Kumar; Kathuria, Sushruta; Ramesh, V

    2017-02-07

    The increase in air pollution over the years has had major effects on the human skin. Various air pollutants such as ultraviolet radiation, polycyclic aromatic hydrocarbons, volatile organic compounds, oxides, particulate matter, ozone and cigarette smoke affect the skin as it is the outermost barrier. Air pollutants damage the skin by inducing oxidative stress. Although human skin acts as a biological shield against pro-oxidative chemicals and physical air pollutants, prolonged or repetitive exposure to high levels of these pollutants may have profound negative effects on the skin. Exposure to ultraviolet radiation has been associated with extrinsic skin aging and skin cancers. Cigarette smoke contributes to premature aging and an increase in the incidence of psoriasis, acne and skin cancers. It is also implicated in allergic skin conditions such as atopic dermatitis and eczema. Polyaromatic hydrocarbons are associated with extrinsic skin aging, pigmentation, cancers and acneiform eruptions. Volatile organic compounds have been associated with atopic dermatitis. Given the increasing levels of air pollution and its detrimental effects on the skin, it is advisable to use strategies to decrease air pollution.

  5. Spoilage of chicken skin at 2 degrees C: electron microscopic study.

    PubMed Central

    Thomas, C J; McMeekin, T A

    1981-01-01

    Microscopic techniques were used in conjunction with normal microbiological procedures to examine the development of the spoilage microflora on the skin of chicken carcasses held at 2 degrees C. Pigmented and nonpigmented psychrotrophic pseudomonads were the major spoilage bacteria isolated at all stages of storage examined. The spoilage microflora grow within a liquid film covering the skin surface, as well as in feather follicle shafts. Penetration and disruption of skin tissue were not observed even after onset of organoleptic spoilage. Bacteria were not attached to the skin by extracellular bridging substances. These data suggest a nonspecific histological-microbiological relationship between he spoilage association and the skin substrate. Images PMID:7195190

  6. Feeling Abnormal: Simulation of Deviancy in Abnormal and Exceptionality Courses.

    ERIC Educational Resources Information Center

    Fernald, Charles D.

    1980-01-01

    Describes activity in which student in abnormal psychology and psychology of exceptional children classes personally experience being judged abnormal. The experience allows the students to remember relevant research, become sensitized to the feelings of individuals classified as deviant, and use caution in classifying individuals as abnormal.…

  7. Regulation of human melanocortin 1 receptor signaling and trafficking by Thr-308 and Ser-316 and its alteration in variant alleles associated with red hair and skin cancer.

    PubMed

    Sánchez-Laorden, Berta L; Jiménez-Cervantes, Celia; García-Borrón, José C

    2007-02-02

    The melanocortin 1 receptor (MC1R), a G protein-coupled receptor (GPCR) positively coupled to adenylyl cyclase, is a key regulator of melanocyte proliferation and differentiation and a determinant of pigmentation, skin phototype, and skin cancer risk. MC1R activation stimulates melanogenesis and increases the ratio of black, strongly photoprotective eumelanins to yellowish and poorly photoprotective pheomelanin pigments. Desensitization and internalization are key regulatory mechanisms of GPCR signaling. Agonist-induced desensitization usually depends on phosphorylation by a GPCR kinase (GRK) followed by receptor internalization in endocytic vesicles. We have shown that MC1R desensitization is mediated by two GRKs expressed in melanocytes and melanoma cells, GRK2 and GRK6. Here we show that in contrast with this dual specificity for desensitization, GRK6 but not GRK2 mediated MC1R internalization. Mutagenesis studies suggested that the targets of GRK6 are two residues located in the MC1R cytosolic C terminus, Thr-308 and Ser-316. A T308D/S316D mutant mimicking their phosphorylated state was constitutively desensitized and associated with endosomes, whereas a T308A/S316A mutant was resistant to desensitization and internalization. We studied the desensitization and internalization of three variant MC1R forms associated with red hair and increased skin cancer risk: R151C, R160W, and D294H. These variants showed a less efficient desensitization. Moreover, D294H was resistant to internalization, thus accounting for its abnormally high surface expression. Co-expression of variant and wild type MC1R modified its desensitization and internalization behavior. These data suggest that MC1R might be regulated by novel mechanisms including differential effects of GRKs and altered desensitization rates of certain allelic combinations.

  8. Skin Findings in Williams Syndrome

    PubMed Central

    Kozel, Beth A.; Bayliss, Susan J.; Berk, David R.; Waxler, Jessica L; Knutsen, Russell H.; Danback, Joshua R.; Pober, Barbara R.

    2014-01-01

    Previous examination in a small number of individuals with Williams syndrome (also referred to as Williams-Beuren syndrome) has shown subtly softer skin and reduced deposition of elastin, an elastic matrix protein important in tissue recoil. No quantitative information about skin elasticity in individuals with Williams syndrome is available; nor has there been a complete report of dermatologic findings in this population. To fill this knowledge gap, 94 patients with Williams syndrome aged 7-50 years were recruited as part of the Skin and Vascular Elasticity (WS-SAVE) study. They underwent either a clinical dermatologic assessment by trained dermatologists (2010 WSA family meeting) or measurement of biomechanical properties of the skin with the DermaLab™ suction cup (2012 WSA family meeting). Clinical assessment confirmed that soft skin is common in this population (83%), as is premature graying of the hair (80% of those 20 years or older), while wrinkles (92%) and abnormal scarring (33%) were detected in larger than expected proportions. Biomechanical studies detected statistically significant differences in dP (the pressure required to lift the skin), dT (the time required to raise the skin through a prescribed gradient), VE (viscoelasticity) and E (Young’s modulus) relative to matched controls. The RT (retraction time) also trended longer but was not significant. The biomechanical differences noted in these patients did not correlate with the presence of vascular defects also attributable to elastin insufficiency (vascular stiffness, hypertension, and arterial stenosis) suggesting the presence of tissue specific modifiers that modulate the impact of elastin insufficiency in each tissue. PMID:24920525

  9. Exercises to Improve Gait Abnormalities

    MedlinePlus

    ... Home About iChip Articles Directories Videos Resources Contact Exercises to Improve Gait Abnormalities Home » Article Categories » Exercise and Fitness Font Size: A A A A Exercises to Improve Gait Abnormalities Next Page The manner ...

  10. Abnormal human sex chromosome constitutions

    SciTech Connect

    1993-12-31

    Chapter 22, discusses abnormal human sex chromosome constitution. Aneuploidy of X chromosomes with a female phenotype, sex chromosome aneuploidy with a male phenotype, and various abnormalities in X chromosome behavior are described. 31 refs., 2 figs.

  11. Leopard syndrome associated with hyperelastic skin: analysis of collagen metabolism in cultured skin fibroblasts.

    PubMed

    Ohkura, T; Ohnishi, Y; Kawada, A; Tajima, S; Ishibashi, A; Ono, K

    1999-01-01

    We present a patient with Leopard syndrome and hyperelastic skin. Biochemical analysis using cultured skin fibroblasts showed normal type III and V collagen synthesis, lysyl hydroxylation level of type I procollagen and processing of pro-alpha(1) and alpha(2)(I). Our results suggest that molecular defects of hyperelasticity in Leopard syndrome are not related to abnormal collagen metabolism, although not all steps of collagen synthesis have been investigated.

  12. Skin Keratins

    PubMed Central

    Wang, Fengrong; Zieman, Abigail; Coulombe, Pierre A.

    2016-01-01

    Keratins comprise the type I and type II intermediate filament-forming proteins and occur primarily in epithelial cells. They are encoded by 54 evolutionarily conserved genes (28 type I, 26 type II) and regulated in a pairwise and tissue type-, differentiation-, and context-dependent manner. Keratins serve multiple homeostatic and stress-enhanced mechanical and nonmechanical functions in epithelia, including the maintenance of cellular integrity, regulation of cell growth and migration, and protection from apoptosis. These functions are tightly regulated by posttranslational modifications as well as keratin-associated proteins. Genetically determined alterations in keratin-coding sequences underlie highly penetrant and rare disorders whose pathophysiology reflects cell fragility and/or altered tissue homeostasis. Moreover, keratin mutation or misregulation represents risk factors or genetic modifiers for several acute and chronic diseases. This chapter focuses on keratins that are expressed in skin epithelia, and details a number of basic protocols and assays that have proven useful for analyses being carried out in skin. PMID:26795476

  13. 5-HT1A/1B Receptors as Targets for Optimizing Pigmentary Responses in C57BL/6 Mouse Skin to Stress

    PubMed Central

    Wu, Hua-Li; Pang, Si-Lin; Liu, Qiong-Zhen; Wang, Qian; Cai, Min-Xuan; Shang, Jing

    2014-01-01

    Stress has been reported to induce alterations of skin pigmentary response. Acute stress is associated with increased turnover of serotonin (5-hydroxytryptamine; 5-HT) whereas chronic stress causes a decrease. 5-HT receptors have been detected in pigment cells, indicating their role in skin pigmentation. To ascertain the precise role of 5-HT in stress-induced pigmentary responses, C57BL/6 mice were subjected to chronic restraint stress and chronic unpredictable mild stress (CRS and CUMS, two models of chronic stress) for 21 days, finally resulting in abnormal pigmentary responses. Subsequently, stressed mice were characterized by the absence of a black pigment in dorsal coat. The down-regulation of tyrosinase (TYR) and tyrosinase-related proteins (TRP1 and TRP2) expression in stressed skin was accompanied by reduced levels of 5-HT and decreased expression of 5-HT receptor (5-HTR) system. In both murine B16F10 melanoma cells and normal human melanocytes (NHMCs), 5-HT had a stimulatory effect on melanin production, dendricity and migration. When treated with 5-HT in cultured hair follicles (HFs), the increased expression of melanogenesis-related genes and the activation of 5-HT1A, 1B and 7 receptors also occurred. The serum obtained from stressed mice showed significantly decreased tyrosinase activity in NHMCs compared to that from nonstressed mice. The decrease in tyrosinase activity was further augmented in the presence of 5-HTR1A, 1B and 7 antagonists, WAY100635, SB216641 and SB269970. In vivo, stressed mice received 5-HT precursor 5-hydroxy-l-tryptophan (5-HTP), a member of the class of selective serotonin reuptake inhibitors (fluoxetine; FX) and 5-HTR1A/1B agonists (8-OH-DPAT/CP94253), finally contributing to the normalization of pigmentary responses. Taken together, these data strongly suggest that the serotoninergic system plays an important role in the regulation of stress-induced depigmentation, which can be mediated by 5-HT1A/1B receptors. 5-HT and 5-HTR1A

  14. Epilepsy and chromosomal abnormalities

    PubMed Central

    2010-01-01

    Background Many chromosomal abnormalities are associated with Central Nervous System (CNS) malformations and other neurological alterations, among which seizures and epilepsy. Some of these show a peculiar epileptic and EEG pattern. We describe some epileptic syndromes frequently reported in chromosomal disorders. Methods Detailed clinical assessment, electrophysiological studies, survey of the literature. Results In some of these congenital syndromes the clinical presentation and EEG anomalies seems to be quite typical, in others the manifestations appear aspecific and no strictly linked with the chromosomal imbalance. The onset of seizures is often during the neonatal period of the infancy. Conclusions A better characterization of the electro clinical patterns associated with specific chromosomal aberrations could give us a valuable key in the identification of epilepsy susceptibility of some chromosomal loci, using the new advances in molecular cytogenetics techniques - such as fluorescent in situ hybridization (FISH), subtelomeric analysis and CGH (comparative genomic hybridization) microarray. However further studies are needed to understand the mechanism of epilepsy associated with chromosomal abnormalities. PMID:20438626

  15. Color characterization of coatings with diffraction pigments.

    PubMed

    Ferrero, A; Bernad, B; Campos, J; Perales, E; Velázquez, J L; Martínez-Verdú, F M

    2016-10-01

    Coatings with diffraction pigments present high iridescence, which needs to be characterized in order to describe their appearance. The spectral bidirectional reflectance distribution functions (BRDFs) of six coatings with SpectraFlair diffraction pigments were measured using the robot-arm-based goniospectrophotometer GEFE, designed and developed at CSIC. Principal component analysis has been applied to study the coatings of BRDF data. From data evaluation and based on theoretical considerations, we propose a relevant geometric factor to study the spectral reflectance and color gamut variation of coatings with diffraction pigments. At fixed values of this geometric factor, the spectral BRDF component due to diffraction is almost constant. Commercially available portable goniospectrophotometers, extensively used in several industries (automotive and others), should be provided with more aspecular measurement angles to characterize the complex reflectance of goniochromatic coatings based on diffraction pigments, but they would not require either more than one irradiation angle or additional out-of-plane geometries.

  16. Induction of Yellow Pigmentation in Serratia marcescens

    PubMed Central

    Trias, Joaquim; Viñas, Miquel; Guinea, Jesús; Lorén, José G.

    1988-01-01

    The appearance of yellow pigmentation in nonpigmented strains of Serratia sp. has been demonstrated to be due to the production of a muconic acid, 2-hydroxy-5-carboxymethylmuconic acid semialdehyde. The 3,4-dihydroxyphenylacetate 2,3-dioxygenase responsible for the synthesis of this muconic acid was induced in all strains tested. Another muconic acid, the β-cis-cis-carboxymuconic acid, could also be synthesized from 3,4-dihydroxybenzoate, but this product was not colored. Mutants that were unable to grow on tyrosine and produced yellow pigment were isolated from nonpigmented strains. These mutants had properties similar to those of the yellow-pigmented strains. The ability to produce pigment may be more widespread among Serratia marcescens strains than is currently known. PMID:16347803

  17. New Directions in Phthalocyanine Pigments

    NASA Technical Reports Server (NTRS)

    Vandemark, Michael R.

    1992-01-01

    The objectives were the following: (1) investigation of the synthesis of new phthalocyanines; (2) characterization of the new phthalocyanines synthesized; (3) investigate the properties of the newly synthesized phthalocyanines with emphasis on UV protection of plastics and coatings; and (4) utilize quantum mechanics to evaluate the structural relationships with possible properties and synthetic approaches. The proposed research targeted the synthesis of phthalocyanines containing an aromatic bridge between two phthalocyanine rings. The goal was to synthesize pigments which would protect plastics when exposed to the photodegradation effects of the sun in space. The stability and extended conjugation of the phthalocyanines offer a unique opportunity for energy absorption and numerous radiative and non-radiative energy loss mechanisms. Although the original targeted phthalocyanines were changed early in the project, several new and unique phthalocyanine compounds were prepared. The basic goals of this work were met and some unique and unexpected outcomes of the work were the result of the integral use of quantum mechanics and molecular modeling with the synthetic effort.

  18. Transient ectopic overexpression of agouti-signalling protein 1 (asip1) induces pigment anomalies in flatfish.

    PubMed

    Guillot, Raúl; Ceinos, Rosa Maria; Cal, Rosa; Rotllant, Josep; Cerdá-Reverter, José Miguel

    2012-01-01

    While flatfish in the wild exhibit a pronounced countershading of the dorso-ventral pigment pattern, malpigmentation is commonly observed in reared animals. In fish, the dorso-ventral pigment polarity is achieved because a melanization inhibition factor (MIF) inhibits melanoblast differentiation and encourages iridophore proliferation in the ventrum. A previous work of our group suggested that asip1 is the uncharacterized MIF concerned. In order to further support this hypothesis, we have characterized asip1 mRNAs in both turbot and sole and used deduced peptide alignments to analyze the evolutionary history of the agouti-family of peptides. The putative asip precursors have the characteristics of a secreted protein, displaying a putative hydrophobic signal. Processing of the potential signal peptide produces mature proteins that include an N-terminal region, a basic central domain with a high proportion of lysine residues as well as a proline-rich region that immediately precedes the C-terminal poly-cysteine domain. The expression of asip1 mRNA in the ventral area was significantly higher than in the dorsal region. Similarly, the expression of asip1 within the unpigmented patches in the dorsal skin of pseudoalbino fish was higher than in the pigmented dorsal regions but similar to those levels observed in the ventral skin. In addition, the injection/electroporation of asip1 capped mRNA in both species induced long term dorsal skin paling, suggesting the inhibition of the melanogenic pathways. The data suggest that fish asip1 is involved in the dorsal-ventral pigment patterning in adult fish, where it induces the regulatory asymmetry involved in precursor differentiation into mature chromatophore. Adult dorsal pseudoalbinism seems to be the consequence of the expression of normal developmental pathways in an inaccurate position that results in unbalanced asip1 production levels. This, in turn, generates a ventral-like differentiation environment in dorsal regions.

  19. Complete resolution of minocycline pigmentation following a single treatment with non-ablative 1550-nm fractional resurfacing in combination with the 755-nm Q-switched alexandrite laser.

    PubMed

    Vangipuram, Ramya K; DeLozier, Whitney L; Geddes, Elizabeth; Friedman, Paul M

    2016-03-01

    Pigmentation secondary to minocycline ingestion is an uncommon adverse event affecting 3.7-14.8% of treated individuals for which few effective therapies are available. Three patterns of minocycline pigmentation have a characteristic clinical and histological appearance. The pigment composition in each variety is different and occurs at varying skin depths. Accordingly, a tailored approach according to the type of minocycline pigmentation is crucial for treatment success. The purpose of this intervention was to evaluate the efficacy of non-ablative fractional photothermolysis in combination with the Q-switched alexandrite laser for the treatment of type I minocycline pigmentation on the face. A patient with type I minocycline pigmentation was treated with non-ablative 1550-nm fractional photothermolysis followed immediately by 755-nm Q-switched alexandrite laser and then observed clinically to determine the outcome of this modality. The patient was seen in clinic 1 month later following her single treatment session and 100% clearance of all blue facial pigment was observed. Non-ablative fractional photothermolysis in combination with the 755-nm Q-switched alexandrite laser should be considered for treatment of type I minocycline pigmentation.

  20. In vivo coherent Raman imaging of the melanomagenesis-associated pigment pheomelanin

    PubMed Central

    Wang, Hequn; Osseiran, Sam; Igras, Vivien; Nichols, Alexander J.; Roider, Elisabeth M.; Pruessner, Joachim; Tsao, Hensin; Fisher, David E.; Evans, Conor L.

    2016-01-01

    Melanoma is the most deadly form of skin cancer with a yearly global incidence over 232,000 patients. Individuals with fair skin and red hair exhibit the highest risk for developing melanoma, with evidence suggesting the red/blond pigment known as pheomelanin may elevate melanoma risk through both UV radiation-dependent and -independent mechanisms. Although the ability to identify, characterize, and monitor pheomelanin within skin is vital for improving our understanding of the underlying biology of these lesions, no tools exist for real-time, in vivo detection of the pigment. Here we show that the distribution of pheomelanin in cells and tissues can be visually characterized non-destructively and noninvasively in vivo with coherent anti-Stokes Raman scattering (CARS) microscopy, a label-free vibrational imaging technique. We validated our CARS imaging strategy in vitro to in vivo with synthetic pheomelanin, isolated melanocytes, and the Mc1re/e, red-haired mouse model. Nests of pheomelanotic melanocytes were observed in the red-haired animals, but not in the genetically matched Mc1re/e; Tyrc/c (“albino-red-haired”) mice. Importantly, samples from human amelanotic melanomas subjected to CARS imaging exhibited strong pheomelanotic signals. This is the first time, to our knowledge, that pheomelanin has been visualized and spatially localized in melanocytes, skin, and human amelanotic melanomas. PMID:27892516

  1. In vivo coherent Raman imaging of the melanomagenesis-associated pigment pheomelanin

    NASA Astrophysics Data System (ADS)

    Wang, Hequn; Osseiran, Sam; Igras, Vivien; Nichols, Alexander J.; Roider, Elisabeth M.; Pruessner, Joachim; Tsao, Hensin; Fisher, David E.; Evans, Conor L.

    2016-11-01

    Melanoma is the most deadly form of skin cancer with a yearly global incidence over 232,000 patients. Individuals with fair skin and red hair exhibit the highest risk for developing melanoma, with evidence suggesting the red/blond pigment known as pheomelanin may elevate melanoma risk through both UV radiation-dependent and -independent mechanisms. Although the ability to identify, characterize, and monitor pheomelanin within skin is vital for improving our understanding of the underlying biology of these lesions, no tools exist for real-time, in vivo detection of the pigment. Here we show that the distribution of pheomelanin in cells and tissues can be visually characterized non-destructively and noninvasively in vivo with coherent anti-Stokes Raman scattering (CARS) microscopy, a label-free vibrational imaging technique. We validated our CARS imaging strategy in vitro to in vivo with synthetic pheomelanin, isolated melanocytes, and the Mc1re/e, red-haired mouse model. Nests of pheomelanotic melanocytes were observed in the red-haired animals, but not in the genetically matched Mc1re/e; Tyrc/c (“albino-red-haired”) mice. Importantly, samples from human amelanotic melanomas subjected to CARS imaging exhibited strong pheomelanotic signals. This is the first time, to our knowledge, that pheomelanin has been visualized and spatially localized in melanocytes, skin, and human amelanotic melanomas.

  2. Microspectrophotometry of Arthropod Visual Screening Pigments

    PubMed Central

    Strother, G. K.; Casella, A. J.

    1972-01-01

    Absorption spectra of visual screening pigments obtained in vitro with a microspectrophotometer using frozen sections are given for the insects Musca domestica, Phormia regina, Libellula luctuosa, Apis mellifera (worker honeybee only), Drosophila melanogaster (wild type only) and the arachnids Lycosa baltimoriana and Lycosa miami. The spectral range covered is 260–700 nm for Lycosa and Drosophila and 310–700 nm for the remainder of the arthropods. A complete description of the instrumentation is given. For the flies, Phormia and Musca, light absorption by the yellow and red pigments is high from 310 to about 610 nm. This implies that for these insects there should be no wavelength shift in electroretinogram (ERG) results due to light leakage among neighboring ommatidia for this wavelength range. The same comment applies to Calliphora erythrocephala, which is known to have similar screening pigments. For some of the insects studied a close correspondence is noted between screening pigment absorption spectra and spectral sensitivity curves for individual photoreceptors, available in the literature. In some cases the screening pigment absorption spectra can be related to chemical extraction results, with the general observation that some of the in vitro absorption peaks are shifted to the red. The Lycosa, Apis, and Libellula dark red pigments absorb strongly over a wide spectral range and therefore prevent chemical identification. PMID:4623852

  3. Attractive skin coloration: harnessing sexual selection to improve diet and health.

    PubMed

    Whitehead, Ross D; Ozakinci, Gözde; Perrett, David I

    2012-12-20

    In this paper we review the mechanisms through which carotenoid coloration could provide a sexually selected cue to condition in species with elaborate color vision. Skin carotenoid pigmentation induced by fruit and vegetable consumption may provide a similar cue to health in humans (particularly light-skinned Asians and Caucasians). Evidence demonstrates that carotenoid-based skin coloration enhances apparent health, and that dietary change can perceptibly impact skin color within weeks. We find that the skin coloration associated with increased fruit and vegetable consumption benefits apparent health to a greater extent than melanin pigmentation. We argue that the benefits to appearance may motivate individuals to improve their diet and that this line of appearance research reveals a potentially powerful strategy for motivating a healthy lifestyle.

  4. Photoprotective role of epidermal melanin granules against ultraviolet damage and DNA repair in guinea pig skin

    SciTech Connect

    Ishikawa, T.; Kodama, K.; Matsumoto, J.; Takayama, S.

    1984-11-01

    We previously developed a quantitative autoradiographic technique with special forceps for measuring unscheduled DNA synthesis (UDS) in mouse skin after treatment with ultraviolet light in vivo. By this method, we investigated the relationship between the protective role of melanin and UV-induced DNA repair in black-and-white guinea pigs. Flat areas containing a sharp border between pigmented and unpigmented skin were selected. The skin of the selected areas was shaved and irradiated with short-wave UV (254 nm) or UV-AB (270 to 440 nm, emission peak at 312 nm) at various doses. Immediately after irradiation, the skin was clamped off with forceps, and an isotonic aqueous solution of (methyl-/sup 3/H)thymidine was injected s.c. into the clamped off portion. UDS was clearly demonstrated as silver grains in this portion of the skin after irradiation with 254 nm UV or UV-AB. Errors due to individual differences were avoided by comparing the intensities of UDS in basal cells from pigmented skin and unpigmented skin of the same animals. Unexpectedly, in groups of animals treated with 254 nm UV or UV-AB, no difference in UDS in pigmented and unpigmented skin was seen at any UV dose. These results suggested that epidermal melanin granules do not significantly protect DNA of basal cells against 254 nm UV or UV-AB irradiation. Results of a study on the effect of the wavelength of irradiation on the UDS response of albino guinea pigs are also reported.

  5. Skin Color, Social Classification, and Blood Pressure in Southeastern Puerto Rico

    PubMed Central

    Gravlee, Clarence C.; Dressler, William W.; Bernard, H. Russell

    2005-01-01

    Objectives. We tested competing hypotheses for the skin color–blood pressure relationship by analyzing the association between blood pressure and 2 skin color variables: skin pigmentation and social classification. Methods. We measured skin pigmentation by reflectance spectrophotometry and social classification by linking respondents to ethnographic data on the cultural model of “color” in southeastern Puerto Rico. We used multiple regression analysis to test the associations between these variables and blood pressure in a community-based sample of Puerto Rican adults aged 25–55 years (n=100). Regression models included age, gender, body mass index (BMI), self-reported use of antihypertensive medication, and socioeconomic status (SES). Results. Social classification, but not skin pigmentation, is associated with systolic and diastolic blood pressure through a statistical interaction with SES, independent of age, gender, BMI, self-reported use of antihypertensive medication, and skin reflectance. Conclusion. Our findings suggest that sociocultural processes mediate the relationship between skin color and blood pressure. They also help to clarify the meaning and measurement of skin color and “race” as social variables in health research. PMID:16257938

  6. Skeletal abnormalities in homocystinuria.

    PubMed Central

    Brenton, D. P.

    1977-01-01

    The skeletal changes of thirty-four patients with the biochemical and clinical features of cystathionine synthase deficiency are described. It is emphasized that there is clinical evidence of excessive bone growth and the formation for bone which is structurally weaker than normal. The similarities and differences between this condition and Marfan's syndrome are stressed and the possible nature of the connective tissue defect leading to the skeletal changes discussed. The most characteristic skeletal changes in homocystinuria are the skeletal disproportion (pubis-heel length greater than crown-pubis length), the abnormal vertebrae, sternal deformities, genu valgum and large metaphyses and epiphyses. Images Fig. 2 Fig. 3 Fig. 4 Fig. 8 Fig. 9 Fig. 10 PMID:917963

  7. Eye movement abnormalities.

    PubMed

    Moncayo, Jorge; Bogousslavsky, Julien

    2012-01-01

    Generation and control of eye movements requires the participation of the cortex, basal ganglia, cerebellum and brainstem. The signals of this complex neural network finally converge on the ocular motoneurons of the brainstem. Infarct or hemorrhage at any level of the oculomotor system (though more frequent in the brain-stem) may give rise to a broad spectrum of eye movement abnormalities (EMAs). Consequently, neurologists and particularly stroke neurologists are routinely confronted with EMAs, some of which may be overlooked in the acute stroke setting and others that, when recognized, may have a high localizing value. The most complex EMAs are due to midbrain stroke. Horizontal gaze disorders, some of them manifesting unusual patterns, may occur in pontine stroke. Distinct varieties of nystagmus occur in cerebellar and medullary stroke. This review summarizes the most representative EMAs from the supratentorial level to the brainstem.

  8. Skin (Pressure) Sores

    MedlinePlus

    ... Treatments and Side Effects Managing Cancer-related Side Effects Skin Problems Pressure Sores A skin or pressure sore ... Content Usage Policy . Skin Problems Dry Skin Itching Skin Color Changes Pressure Sores Scars ... and Paying for Treatment Treatments and Side Effects Survivorship: During and After Treatment Caregivers and Family ...

  9. 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.

  10. Tumors of the skin and soft tissues

    SciTech Connect

    Weller, R.E.

    1991-10-01

    The majority of the body surface is covered by the skin. Many internal disorders are reflected in the condition of the skin. One of the major functions of the skin is protection of the other organ systems from a variety of environmental insults. In this role, the skin itself is exposed to factors that can ultimately cause chronic diseases and cancer. Since it is relatively easy to recognize skin abnormalities, most skin cancers are brought to professional attention sooner than other types of cancer. However, due to the close resemblance between many skin neoplasms and noncancerous dermatologic disorders, these neoplasms may be mistreated for months or even years. In veterinary oncology, as in human medicine, most cancers can be effectively treated or cured following an accurate diagnosis. Once diagnosed, skin neoplasms should be aggressively treated. If causal factors are known, exposure to these factors should be limited through removal of the agent (for chemical carcinogens) or limiting exposure to the agent (for other carcinogens such as sunlight). 10 tabs. (MHB)

  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. Association of skin color, race/ethnicity, and hearing loss among adults in the USA.

    PubMed

    Lin, Frank R; Maas, Paige; Chien, Wade; Carey, John P; Ferrucci, Luigi; Thorpe, Roland

    2012-02-01

    Epidemiologic studies of hearing loss in adults have demonstrated that the odds of hearing loss are substantially lower in black than in white individuals. The basis of this association is unknown. We hypothesized that skin pigmentation as a marker of melanocytic functioning mediates this observed association and that skin pigmentation is associated with hearing loss independent of race/ethnicity. We analyzed cross-sectional data from 1,258 adults (20-59 years) in the 2003-2004 cycle of the National Health and Nutritional Examination Survey who had assessment of Fitzpatrick skin type and pure-tone audiometric testing. Audiometric thresholds in the worse hearing ear were used to calculate speech- (0.5-4 kHz) and high-frequency (3-8 kHz) pure-tone averages (PTA). Regression models were stratified by Fitzpatrick skin type or race/ethnicity to examine the association of each factor with hearing loss independent of the other. Models were adjusted for potential confounders (demographic, medical, and noise exposure covariates). Among all participants, race/ethnicity was associated with hearing thresholds (black participants with the best hearing followed by Hispanics and then white individuals), but these associations were not significant in analyses stratified by skin color. In contrast, in race-stratified analyses, darker-skinned Hispanics had better hearing than lighter-skinned Hispanics by an average of -2.5 dB hearing level (HL; 95% CI, -4.8 to -0.2) and -3.1 dB HL (95% CI, -5.3 to -0.8) for speech and high-frequency PTA, respectively. Associations between skin color and hearing loss were not significant in white and black participants. Our results demonstrate that skin pigmentation is independently associated with hearing loss in Hispanics and suggest that skin pigmentation as a marker of melanocytic functioning may mediate the strong association observed between race/ethnicity and hearing loss.

  13. Cultured Skin Substitutes Reduce Donor Skin Harvesting for Closure of Excised, Full-Thickness Burns

    PubMed Central

    Boyce, Steven T.; Kagan, Richard J.; Yakuboff, Kevin P.; Meyer, Nicholas A.; Rieman, Mary T.; Greenhalgh, David G.; Warden, Glenn D.

    2002-01-01

    Objective Comparison of cultured skin substitutes (CSS) and split-thickness skin autograft (AG) was performed to assess whether donor-site harvesting can be reduced quantitatively and whether functional and cosmetic outcome is similar qualitatively in the treatment of patients with massive cutaneous burns. Summary Background Data Cultured skin substitutes consisting of collagen-glycosaminoglycan substrates populated with autologous fibroblasts and keratinocytes have been shown to close full-thickness skin wounds in preclinical and clinical studies with acceptable functional and cosmetic results. Methods Qualitative outcome was compared between CSS and AG in 45 patients on an ordinal scale (0, worst; 10, best) with primary analyses at postoperative day 28 and after about 1 year for erythema, pigmentation, pliability, raised scar, epithelial blistering, and surface texture. In the latest 12 of the 45 patients, tracings were performed of donor skin biopsies and wounds treated with CSS at postoperative days 14 and 28 to calculate percentage engraftment, the ratio of closed wound:donor skin areas, and the percentage of total body surface area closed with CSS. Results Measures of qualitative outcome of CSS or AG were not different statistically at 1 year after grafting. Engraftment at postoperative day 14 exceeded 75% in the 12 patients evaluated. The ratio of closed wound:donor skin areas for CSS at postoperative day 28 was significantly greater than for conventional 4:1 meshed autografts. The percentage of total body surface area closed with CSS at postoperative day 28 was significantly less than with AG. Conclusions The requirement for harvesting of donor skin for CSS was less than for conventional skin autografts. These results suggest that acute-phase recovery of patients with extensive burns is facilitated and that complications are reduced by the use of CSS together with conventional skin grafting. PMID:11807368

  14. The skin and hypercoagulable states.

    PubMed

    Thornsberry, Laura A; LoSicco, Kristen I; English, Joseph C

    2013-09-01

    Hypercoagulable states (HS) are inherited or acquired conditions that predispose an individual to venous and/or arterial thrombosis. The dermatologist can play a vital role in diagnosing a patient's HS by recognizing the associated cutaneous manifestations, such as purpura, purpura fulminans, livedo reticularis, livedo vasculopathy (atrophie blanche), anetoderma, chronic venous ulcers, and superficial venous thrombosis. The cutaneous manifestations of HS are generally nonspecific, but identification of an abnormal finding can warrant a further workup for an underlying thrombophilic disorder. This review will focus on the basic science of hemostasis, the evaluation of HS, the skin manifestations associated with hypercoagulability, and the use of antiplatelet and anticoagulant therapy in dermatology.

  15. pH-Regulated Mechanisms Account for Pigment-Type Differences in Epidermal Barrier Function

    PubMed Central

    Gunathilake, Roshan; Schurer, Nanna Y.; Shoo, Brenda A.; Celli, Anna; Hachem, Jean-Pierre; Crumrine, Debra; Sirimanna, Ganga; Feingold, Kenneth R.; Mauro, Theodora M.; Elias, Peter M.

    2009-01-01

    To determine whether pigment type determines differences in epidermal function, we studied stratum corneum (SC) pH, permeability barrier homeostasis, and SC integrity in three geographically disparate populations with pigment type I–II versus IV–V skin (Fitzpatrick I–VI scale). Type IV–V subjects showed: (i) lower surface pH (≈0.5 U); (ii) enhanced SC integrity (transepidermal water loss change with sequential tape strippings); and (iii) more rapid barrier recovery than type I–II subjects. Enhanced barrier function could be ascribed to increased epidermal lipid content, increased lamellar body production, and reduced acidity, leading to enhanced lipid processing. Compromised SC integrity in type I–II subjects could be ascribed to increased serine protease activity, resulting in accelerated desmoglein-1 (DSG-1)/corneodesmosome degradation. In contrast, DSG-1-positive CDs persisted in type IV–V subjects, but due to enhanced cathepsin-D activity, SC thickness did not increase. Adjustment of pH of type I–II SC to type IV–V levels improved epidermal function. Finally, dendrites from type IV–V melanocytes were more acidic than those from type I–II subjects, and they transfer more melanosomes to the SC, suggesting that melanosome secretion could contribute to the more acidic pH of type IV–V skin. These studies show marked pigment-type differences in epidermal structure and function that are pH driven. PMID:19177137

  16. Dermatoscopy-guided therapy of pigmented basal cell carcinoma with imiquimod*

    PubMed Central

    Husein-ElAhmed, Husein; Fernandez-Pugnaire, Maria Antonia

    2016-01-01

    BACKGROUND Dermatoscopy is a non-invasive diagnostic tool used to examine skin lesions with an optical magnification. It has been suggested as a useful tool for monitoring therapeutic response in lentigo maligna patients treated with imiquimod. OBJECTIVE To examine the accuracy of dermatoscopy as a tool to monitor the therapeutic response of pigmented basal cell carcinoma treated with imiquimod. METHOD The authors designed a prospective study. Patients with pigmented basal cell carcinoma were included and data regarding the dermatoscopy features were collected following the Menzies criteria, prior to initiating the imiquimod treatment. Subsequent dermatoscopic evaluations were performed at weeks 4 and 8, following imiquimod discontinuation. RESULTS Twenty lesions were included. The most common pigmented dermatoscopy features were large blue-grey ovoid nests (80%), followed by blue-grey globules (50%) and leaf-like areas (30%). No spoke wheel areas were observed. In 17 out of 20 patients, a response was noted during the first evaluation at 4 weeks, while the clearance was noted at the second check-up after 8 weeks. In two patients, the clearance was found at the initial evaluation at 4 weeks, while in one patient, the response remained unchanged. Blue-grey globules were the fastest to exhibit clearance (50% at week 4), followed by leaf-like areas (15%) and large blue-grey ovoid nests (6.25%). CONCLUSION According to our results, dermatoscopic evaluation enhances the accuracy in the assessment of the clinical response to imiquimod in pigmented basal cell carcinoma. PMID:28099598

  17. Inhibitory effect of rose hip (Rosa canina L.) on melanogenesis in mouse melanoma cells and on pigmentation in brown guinea pigs.

    PubMed

    Fujii, Takashi; Ikeda, Katsumi; Saito, Morio

    2011-01-01

    The compounds present in rose hips exerting an inhibitory action against melanogenesis in B16 mouse melanoma cells were investigated by dividing an aqueous extract of rose hips (RE) into four fractions. The 50% ethanol eluate from a DIAION HP-20 column significantly reduced the production of melanin and was mainly composed of procyanidin glycosides. We also found that this 50% ethanol eluate reduced the intracellular tyrosinase activity and also had a direct inhibitory effect on tyrosinase obtained as a protein mixture from the melanoma cell lysate. We also investigated the effect of orally administering RE on skin pigmentation in brown guinea pigs, and found that the pigmentation was inhibited together with the tyrosinase activity in the skin. These data collectively suggest that proanthocyanidins from RE inhibited melanogenesis in mouse melanoma cells and guinea pig skin, and could be useful as a skin-whitening agent when taken orally.

  18. Treatment Options for Congenital Pigmented Nevus

    MedlinePlus

    ... Now Open Conference Schedule Highlights Fundraiser Advice Holiday Shopping at Amazon Happy In My Skin Congenital Nevus ... Now Open Conference Schedule Highlights Fundraiser Advice Holiday Shopping at Amazon Happy In My Skin Congenital Nevus ...

  19. Stages of Skin Cancer

    MedlinePlus

    ... Skin Cancer Skin color and being exposed to sunlight can increase the risk of nonmelanoma skin cancer ... carcinoma include the following: Being exposed to natural sunlight or artificial sunlight (such as from tanning beds) ...

  20. Skin Cancer Treatment

    MedlinePlus

    ... Skin Cancer Skin color and being exposed to sunlight can increase the risk of nonmelanoma skin cancer ... carcinoma include the following: Being exposed to natural sunlight or artificial sunlight (such as from tanning beds) ...

  1. Basal cell skin cancer

    MedlinePlus

    ... occur on skin that is regularly exposed to sunlight or other ultraviolet radiation. This type of skin ... skin cancer is to reduce your exposure to sunlight . Always use sunscreen: Apply sunscreen with sun protection ...

  2. Skin Condition Finder

    MedlinePlus

    ... SKIN CONDITIONS HEALTH TOPICS FOR PROFESSIONALS Rash and Skin Condition Finder 1 Select Age Group Infant Child ... Toe Toe Webspace Toe Nail CLOSE About the Skin Condition Finder Have a health question or concern? ...

  3. Skin Complications of IBD

    MedlinePlus

    ... Home > Resources > Skin Complications of IBD Go Back Skin Complications of IBD Email Print + Share After arthritis, ... about 5% of people with inflammatory bowel disease. SKIN DISORDERS COMMONLY SEEN IN IBD ERHTHEMA NODOSUM The ...

  4. Scalded skin syndrome

    MedlinePlus

    Ritter disease; Staphylococcal scalded skin syndrome (SSS) ... Scalded skin syndrome (SSS) is caused by infection with certain strains of Staphylococcus bacteria. The bacteria produce a toxin that causes the skin ...

  5. Skin Allergy Quiz

    MedlinePlus

    ... time. Some common medications that can cause skin allergy include penicillin, sulfa drugs, barbiturates and anticonvulsants just to mention a few. Some of the symptoms from drug allergies might be hives, skin rash, itchy skin or ...

  6. Learning about Skin Cancer

    MedlinePlus

    ... Why Deadly Skin Cancers Spread 2000 News Release Learning About Skin Cancer What are the most common ... skin surface. When a melanoma becomes thick and deep, the disease often spreads to other parts of ...

  7. Ultrastructure: effects of melanin pigment on target specificity using a pulsed dye laser (577 nm)

    SciTech Connect

    Tong, A.K.; Tan, O.T.; Boll, J.; Parrish, J.A.; Murphy, G.F.

    1987-06-01

    It has been shown recently that brief pulses of 577 nm radiation from the tunable dye laser are absorbed selectively by oxyhemoglobin. This absorption is associated with highly specific damage to superficial vascular plexus blood vessels in those with lightly pigmented (type I-II) skin. To determine whether pigmentary differences in the overlying epidermis influence this target specificity, we exposed both type I (fair) and type V (dark) normal human skin to varying radiant exposure doses over 1.5-microsecond pulse durations from the tunable dye laser at a wavelength of 577 nm. Using ultrastructural techniques, we found in type I skin that even clinical subthreshold laser exposures caused reproducible alterations of erythrocytes and adjacent dermal vascular endothelium without comparable damage to the overlying epidermis. In contrast, degenerated epidermal basal cells represented the predominant form of cellular damage after laser exposure of type V skin at comparable doses. We conclude that epidermal melanin and vascular hemoglobin are competing sites for 577 nm laser absorption and damage, and that the target specificity of the 577 nm tunable dye laser is therefore influenced by variations in epidermal pigmentation. This finding is relevant to the clinical application of the tunable dye laser in the ablative treatment of vascular lesions. We also found on ultrastructure that the presence of electron-lucent circular structures of approximately 800 A in diameter were observed only at and above clinical threshold doses in those with type I skin and at the highest dose of 2.75 J/cm2 in type V skin. It has been proposed that these structures might be heat-fixed molds of water vapor. Both this and ultrastructural changes of epidermal basal cells demonstrate mechanisms responsible for alteration of tissue after exposure to 577 nm, which are discussed.

  8. Effects of visible light on the skin.

    PubMed

    Mahmoud, Bassel H; Hexsel, Camile L; Hamzavi, Iltefat H; Lim, Henry W

    2008-01-01

    Electromagnetic radiation has vast and diverse effects on human skin. Although photobiologic studies of sunlight date back to Sir Isaac Newton in 1671, most available studies focus on the UV radiation part of the spectrum. The effects of visible light and infrared radiation have not been, until recently, clearly elucidated. The goal of this review is to highlight the effects of visible light on the skin. As a result of advances in the understanding of skin optics, and comprehensive studies regarding the absorption spectrum of endogenous and exogenous skin chromophores, various biologic effects have been shown to be exerted by visible light radiation including erythema, pigmentation, thermal damage and free radical production. It has also been shown that visible light can induce indirect DNA damage through the generation of reactive oxygen species. Furthermore, a number of photodermatoses have an action spectrum in the visible light range, even though most of the currently available sunscreens offer, if any, weak protection against visible light. Conversely, because of its cutaneous biologic effects, visible light is used for the treatment of a variety of skin diseases and esthetic conditions in the form of lasers, intense pulsed light and photodynamic therapy.

  9. Characterization of suspected illegal skin whitening cosmetics.

    PubMed

    Desmedt, B; Van Hoeck, E; Rogiers, V; Courselle, P; De Beer, J O; De Paepe, K; Deconinck, E

    2014-03-01

    An important group of suspected illegal cosmetics consists of skin bleaching products, which are usually applied to the skin of the face, hands and décolleté for local depigmentation of hyper pigmented regions or more importantly, for a generalized reduction of the skin tone. These cosmetic products are suspected to contain illegal active substances that may provoke as well local as systemic toxic effects, being the reason for their banning from the EU market. In that respect, illegal and restricted substances in cosmetics, known to have bleaching properties, are in particular hydroquinone, tretinoin and corticosteroids. From a legislative point of view, all cosmetic products containing a prohibited whitening agent are illegal and must be taken off the EU market. A newly developed screening method using ultra high performance liquid chromatography-time off flight-mass spectrometry allows routine analysis of suspected products. 163 suspected skin whitening cosmetics, collected by Belgian inspectors at high risk sites such as airports and so-called ethnic cosmetic shops, were analyzed and 59% were classified as illegal. The whitening agents mostly detected were clobetasol propionate and hydroquinone, which represent a serious health risk when repeatedly and abundantly applied to the skin.

  10. Potential natural sensitizers extracted from the skin of Canarium odontophyllum fruits for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Lim, Andery; Kumara, N. T. R. N.; Tan, Ai Ling; Mirza, Aminul Huq; Chandrakanthi, R. L. N.; Petra, Mohammad Iskandar; Ming, Lim Chee; Senadeera, G. K. R.; Ekanayake, Piyasiri

    2015-03-01

    Possibility of use of dye extract from skin samples of a seasonal, indigenous fruit from Borneo, namely Canarium odontophyllum, in dye sensitized solar cells (DSSCs) are explored. Three main groups of flavonoid pigments are detected and these pigments exhibit different UV-vis absorption properties, and hence showing different light harvesting capabilities. When applied in DSSCs. The detected pigment constituents of the extract consist of aurone (maritimein), anthocyanidin (pelargonidin) and anthocyanidin (cyanidin derivatives). When tested in DSSC, the highest conversion efficiency of 1.43% is exhibited by cyanidin derivatives, and this is followed by conversion efficiencies of 0.51% and 0.79% for aurone and pelargonidin, respectively. It is shown that individual pigments, like cyanidin derivatives and pelargonidin, exhibit higher power conversion efficiency when compared to that of C.odontophyllum skin pigment mixture (with a conversion efficiency of only 0.68%). The results indicate a possibility of masking effects of the pigments when used as a mixture. The acidification of C.odontophyllum skin pigments with concentrated hydrochloric acid improves the conversion efficiency of the mixture from 0.68% to 0.99%. The discussion in this paper will draw data and observations from the variation in absorption and adsorption properties, the HOMO-LUMO levels, the energy band gaps and the functional group compositions of the detected flavonoids.

  11. Potential natural sensitizers extracted from the skin of Canarium odontophyllum fruits for dye-sensitized solar cells.

    PubMed

    Lim, Andery; Kumara, N T R N; Tan, Ai Ling; Mirza, Aminul Huq; Chandrakanthi, R L N; Petra, Mohammad Iskandar; Ming, Lim Chee; Senadeera, G K R; Ekanayake, Piyasiri

    2015-03-05

    Possibility of use of dye extract from skin samples of a seasonal, indigenous fruit from Borneo, namely Canarium odontophyllum, in dye sensitized solar cells (DSSCs) are explored. Three main groups of flavonoid pigments are detected and these pigments exhibit different UV-vis absorption properties, and hence showing different light harvesting capabilities. When applied in DSSCs. The detected pigment constituents of the extract consist of aurone (maritimein), anthocyanidin (pelargonidin) and anthocyanidin (cyanidin derivatives). When tested in DSSC, the highest conversion efficiency of 1.43% is exhibited by cyanidin derivatives, and this is followed by conversion efficiencies of 0.51% and 0.79% for aurone and pelargonidin, respectively. It is shown that individual pigments, like cyanidin derivatives and pelargonidin, exhibit higher power conversion efficiency when compared to that of C.odontophyllum skin pigment mixture (with a conversion efficiency of only 0.68%). The results indicate a possibility of masking effects of the pigments when used as a mixture. The acidification of C.odontophyllum skin pigments with concentrated hydrochloric acid improves the conversion efficiency of the mixture from 0.68% to 0.99%. The discussion in this paper will draw data and observations from the variation in absorption and adsorption properties, the HOMO-LUMO levels, the energy band gaps and the functional group compositions of the detected flavonoids.

  12. Increased alpha-melanocyte-stimulating hormone (alpha-MSH) levels and melanocortin receptors expression associated with pigmentation in an NC/Nga mouse model of atopic dermatitis.

    PubMed

    Hiramoto, Keiichi; Kobayashi, Hiromi; Ishii, Masamitsu; Sato, Eisuke; Inoue, Masayasu

    2010-02-01

    Patients with a specific subtype of atopic dermatitis (AD) display particular patterns of pigmentation, such as ripple pattern pigmentation on the neck, pigmented macules on the lip and diffuse pigmentation. However, the mechanism underlying these patterns has not been determined. The purpose of our research is to investigate the factors influencing this type of pigmentation in AD. We observed that AD model mice (NC/Nga mice) displayed an increase in the number of 3, 4-dihydroxyphenylalanine (Dopa)-positive melanocytes in the epidermis and intestine (jejunum and colon) while in the inflammatory state. The plasma levels of alpha-melanocyte-stimulating hormone (alpha-MSH) and adrenocoticotropin (ACTH) also increased in NC/Nga mice with dermatitis. Furthermore, the expression of melanocortin receptor 5 and melanocortin receptor 1 (MC1R) increased in the skin, and melanocortin receptor 3 (MC3R) expression increased in the intestine. However, the changes in the Dopa-positive cells of conventional NC/Nga mice were not induced by treatment with either agouti (an MC1R antagonist) or agouti-related protein (an MC3R antagonist). These results indicate that the pigmentation of AD is related to increased levels of alpha-MSH, MC1R (in the skin) and MC3R (in the intestines).

  13. Pigmented eccrine poroma: dermoscopic and confocal features

    PubMed Central

    Bombonato, Caterina; Piana, Simonetta; Moscarella, Elvira; Lallas, Aimillios; Argenziano, Giuseppe; Longo, Caterina

    2016-01-01

    Eccrine poroma is a rare benign adnexal tumor of epithelial cells originating from the terminal ductal portion of the sweat glands that is typically located on palms and soles, although other cutaneous sites can be affected [1]. It is usually nonpigmented even if there is a pigmented variant that corresponds to 17% of cases and it is usually underdiagnosed, since it is mistakenly confused with other pigmented tumors [2,3]. Dermoscopy and reflectance confocal microscopy (RCM) may assist in the correct diagnosis of this tumor. Herein, we report one case of pigmented eccrine poroma (PEP) that simulated clinically a cutaneous melanoma or a basal cell carcinoma. Dermoscopy and RCM excluded the possibilities of those two diagnoses; the overall confocal findings were suggestive for a benign epithelial tumor. Histology was fundamental to diagnose this lesion as a pigmented eccrine poroma. Even if the diagnosis of eccrine poroma remains histopathological still, as in this case report, noninvasive tools such as dermoscopy and RCM examinations can be of help to rule out the diagnosis of melanoma. Larger studies on this rare pigmented variant of eccrine poroma could shed new light on the identification of specific diagnostic dermoscopic and confocal features. PMID:27648386

  14. Inadvertent polychlorinated biphenyls in commercial paint pigments.

    PubMed

    Hu, Dingfei; Hornbuckle, Keri C

    2010-04-15

    A polychlorinated biphenyl (PCB) that was not produced as part of the Aroclor mixtures banned in the 1980s was recently reported in air samples collected in Chicago, Philadelphia, the Arctic, and several sites around the Great Lakes. In Chicago, the congener 3,3'-dichlorobiphenyl or PCB11 was found to be the fifth most concentrated congener and ubiquitous throughout the city. The congener exhibited strong seasonal concentration trends that suggest volatilization of this compound from common outdoor surfaces. Due to these findings and also the compound's presence in waters that received waste from paint manufacturing facilities, we hypothesized that PCB11 may be present in current commercial paint. In this study we measured PCBs in paint sold on the current retail market. We tested 33 commercial paint pigments purchased from three local paint stores. The pigment samples were analyzed for all 209 PCB congeners using gas chromatography with tandem mass spectrometry (GC-MS/MS). More than 50 PCB congeners including several dioxin-like PCBs were detected, and the PCB profiles varied due to different types of pigments and different manufacturing processes. PCB congeners were detected in azo and phthalocyanine pigments which are commonly used in paint but also in inks, textiles, paper, cosmetics, leather, plastics, food and other materials. Our findings suggest several possible mechanisms for the inadvertent production of specific PCB congeners during the manufacturing of paint pigments.

  15. Investigations of biomimetic light energy harvesting pigments

    SciTech Connect

    Van Patten, P.G.; Donohoe, R.J.; Lindsey, J.S.; Bocian, D.F.

    1998-12-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). Nature uses chlorophyll and other porphyrinic pigments to capture and transfer light energy as a preliminary step in photosynthesis. The design of synthetic assemblies of light harvesting and energy directing pigments has been explored through synthesis and characterization of porphyrin oligomers. In this project, pigment electronic and vibrational structures have been explored by electrochemistry and dynamic and static optical measurements. Transient absorption data reveal energy transfer between pigments with lifetimes on the order of 20--200 picoseconds, while Raman data reveal that the basic porphyrin core structure is unperturbed relative to the individual monomer units. These two findings, along with an extensive series of experiments on the oxidized oligomers, reveal that coupling between the pigments is fundamentally weak, but sufficient to allow facile energy transfer as the predominant excited state process. Modeling of the expected quantum yields for energy transfer within a variety of arrays was accomplished, thereby providing a tool to guide synthetic goals.

  16. Recreating a functional ancestral archosaur visual pigment.

    PubMed

    Chang, Belinda S W; Jönsson, Karolina; Kazmi, Manija A; Donoghue, Michael J; Sakmar, Thomas P

    2002-09-01

    The ancestors of the archosaurs, a major branch of the diapsid reptiles, originated more than 240 MYA near the dawn of the Triassic Period. We used maximum likelihood phylogenetic ancestral reconstruction methods and explored different models of evolution for inferring the amino acid sequence of a putative ancestral archosaur visual pigment. Three different types of maximum likelihood models were used: nucleotide-based, amino acid-based, and codon-based models. Where possible, within each type of model, likelihood ratio tests were used to determine which model best fit the data. Ancestral reconstructions of the ancestral archosaur node using the best-fitting models of each type were found to be in agreement, except for three amino acid residues at which one reconstruction differed from the other two. To determine if these ancestral pigments would be functionally active, the corresponding genes were chemically synthesized and then expressed in a mammalian cell line in tissue culture. The expressed artificial genes were all found to bind to 11-cis-retinal to yield stable photoactive pigments with lambda(max) values of about 508 nm, which is slightly redshifted relative to that of extant vertebrate pigments. The ancestral archosaur pigments also activated the retinal G protein transducin, as measured in a fluorescence assay. Our results show that ancestral genes from ancient organisms can be reconstructed de novo and tested for function using a combination of phylogenetic and biochemical methods.

  17. Epidemiological Assessments of Skin Outcomes in the Nurses’ Health Studies

    PubMed Central

    Li, Wen-Qing; Cho, Eunyoung; Weinstock, Martin A.; Mashfiq, Hasan

    2016-01-01

    Objectives. To review the contribution of the Nurses’ Health Studies (NHSs) to identifying epidemiological factors associated with multiple skin diseases, including skin cancer, psoriasis, and other inflammatory and autoimmune skin diseases. Methods. We carried out a narrative review of NHS articles published between 1976 and 2016. Results. The NHSs have identified environmental and lifestyle factors related to psoriasis, supporting obesity and smoking as psoriasis risk factors; associations between psoriasis and diabetes, myocardial infarction, and Crohn’s disease, supporting psoriasis as a systemic disorder; and associations of pigmentary traits, ultraviolet radiation, and lifestyle factors such as citrus consumption with risk of skin cancer. Genetic studies have identified novel genetic loci for skin pigmentation (e.g., IRF4, SLC24A4, NID1, and EDNRB) and skin cancer (e.g., TET2 and HERC2-OCA2). Work continues on highly prevalent but less studied skin conditions such as rosacea, acne, and atopic dermatitis. The NHS results have influenced public health policies on indoor tanning devices. Conclusions. The NHSs have provided invaluable resources on skin disease population science and contributed to the etiological understanding of multiple skin disorders. PMID:27459457

  18. Bioactive compounds from natural resources against skin aging.

    PubMed

    Mukherjee, Pulok K; Maity, Niladri; Nema, Neelesh K; Sarkar, Birendra K

    2011-12-15

    Skin aging involves degradation of extracellular matrix (ECM) in both the epidermal and dermal layers, it leaves visible signs on the surface of skin and the physical properties of the skin are modified. Chronological aging is due to passage of time, whereas premature aging occurred due to some environmental factors on skin produces visible signs such as irregular dryness, dark/light pigmentation, sallowness, severe atrophy, telangiectases, premalignant lesions, laxity, leathery appearance and deep wrinkling. There are several synthetic skincare cosmetics existing in the market to treat premature aging and the most common adverse reactions of those include allergic contact dermatitis, irritant contact dermatitis, phototoxic and photo-allergic reactions. Recent trends in anti-aging research projected the use of natural products derived from ancient era after scientific validation. Ample varieties of phytomolecules such as aloin, ginsenoside, curcumin, epicatechin, asiaticoside, ziyuglycoside I, magnolol, gallic acid, hydroxychavicol, hydroxycinnamic acids, hydroxybenzoic acids, etc. scavenges free radicals from skin cells, prevent trans-epidermal water loss, include a sun protection factor (SPF) of 15 or higher contribute to protect skin from wrinkles, leading to glowing and healthy younger skin. Present era of treating aging skin has become technologically more invasive; but herbal products including botanicals are still relevant and combining them with molecular techniques outlined throughout this review will help to maximize the results and maintain the desired anti-skin aging benefits.

  19. Evaluation of skin cancer risk for lunar and Mars missions

    NASA Astrophysics Data System (ADS)

    Kim, Myung-Hee Y.; George, Kerry A.; Cucinotta, Francis A.

    Methods used to estimate the probability of excess incidence of skin cancer from space radiation exposure must take into consideration the variability of dose to different areas of the body and the individual factors that may contribute to increased risk, including skin pigment and synergistic effects from combined ionizing and UV exposure. We have estimated the skin cancer risk for future lunar and Mars missions using: (1) the multiplicative risk model for transferring the Japanese survivor data to the US population, (2) epidemiological data for the increased risk for skin locations exposed to combined UV and ionizing radiation, and (3) models of space radiation environments, transport, and anatomical shielding for 5260 skin loci. We have estimated that the probability for increased skin cancer risk from solar particle events varies more than 10-fold depending on the individual and area of skin exposed. We show that a skin cancer risk greater than 1% could occur for astronauts with light skin and hair color following exposure to medium or large class solar particle events during future lunar base operations, or from exposure to galactic cosmic rays during Mars missions.

  20. Skin Color Variation in Orang Asli Tribes of Peninsular Malaysia

    PubMed Central

    Ang, Khai C.; Ngu, Mee S.; Reid, Katherine P.; Teh, Mei S.; Aida, Zamzuraida S.; Koh, Danny XR.; Berg, Arthur; Oppenheimer, Stephen; Salleh, Hood; Clyde, Mahani M.; Md-Zain, Badrul M.; Canfield, Victor A.; Cheng, Keith C.

    2012-01-01

    Pigmentation is a readily scorable and quantitative human phenotype, making it an excellent model for studying multifactorial traits and diseases. Convergent human evolution from the ancestral state, darker skin, towards lighter skin colors involved divergent genetic mechanisms in people of European vs. East Asian ancestry. It is striking that the European mechanisms result in a 10–20-fold increase in skin cancer susceptibility while the East Asian mechanisms do not. Towards the mapping of genes that contribute to East Asian pigmentation there is need for one or more populations that are admixed for ancestral and East Asian ancestry, but with minimal European contribution. This requirement is fulfilled by the Senoi, one of three indigenous tribes of Peninsular Malaysia collectively known as the Orang Asli. The Senoi are thought to be an admixture of the Negrito, an ancestral dark-skinned population representing the second of three Orang Asli tribes, and regional Mongoloid populations of Indo-China such as the Proto-Malay, the third Orang Asli tribe. We have calculated skin reflectance-based melanin indices in 492 Orang Asli, which ranged from 28 (lightest) to 75 (darkest); both extremes were represented in the Senoi. Population averages were 56 for Negrito, 42 for Proto-Malay, and 46 for Senoi. The derived allele frequencies for SLC24A5 and SLC45A2 in the Senoi were 0.04 and 0.02, respectively, consistent with greater South Asian than European admixture. Females and individuals with the A111T mutation had significantly lighter skin (p = 0.001 and 0.0039, respectively). Individuals with these derived alleles were found across the spectrum of skin color, indicating an overriding effect of strong skin lightening alleles of East Asian origin. These results suggest that the Senoi are suitable for mapping East Asian skin color genes. PMID:22912732

  1. Novel skin brightener used as monotherapy for moderate melasma in skin of color.

    PubMed

    Grimes, Pearl E

    2014-03-01

    Melasma is a chronic, relapsing disorder that can be disfiguring and can have adverse effects on quality of life. Recently, a unique hydroquinone-free topical product addressing multiple pathways involved in pigmentation was shown to have similar efficacy and equally well tolerated as 4% hydroquinone in females with facial hyperpigmentation. The goal herein was to further assess the efficacy and tolerability of this new multimodality product for the control of moderate melasma in skin of color. Six female subjects with Fitzpatrick skin types IV-V in good general health between the ages of 46 and 63 years with moderate epidermal facial melasma are presented herein. Subjects applied the skin brightener twice daily, morning and evening, and returned to the clinic at weeks 4, 8, and 12. By week 12, Investigator Overall Hyperpigmentation scores and MASI scores improved by an average of 22% and 38% from baseline, respectively. Additionally, 100% of subjects showed at least a 25% increase in Global Improvement at week 12. The skin brightener was well tolerated with no reports of erythema, edema, scaling, burning/stinging, or itching. Results from these case studies suggest that this multimodality skin brightener may provide an alternative treatment to hydroquinone for moderate melasma in skin of color. However additional clinical studies would be needed.

  2. An erupted odontoma associated with pigmentation: a histogenetic and histological perspective.

    PubMed

    Kaur, Gurkiran A; Sivapathasundharam, B; Berkovitz, Barry K; Radhakrishnan, Raghu A

    2012-01-01

    Odontomas are hamartomatous malformations of odontogenic origin composed of all the structures that form the tooth. Pigmentation associated with odontomas is rare, with only two cases reported in the literature. The genesis of this composite malformation is attributable to the organizational failure of the developing odontogenic apparatus leading to abnormal morphodifferentiation. Although some odontomas erupt into the oral cavity, it defies the existing views of normal physiologic tooth movement thus raising questions over the use of this term. Here, we review a case of large odontoma in a 23-year-old male surfacing into the oral cavity from its intraosseous location. The unusual occurrence of melanotic pigmentation in the odontogenic epithelial rests was demonstrated by Mason Fontana special stain. The histogenesis of this unusual entity and explanation to its possible occurrence is discussed.

  3. New antiepileptic medication linked to blue discoloration of the skin and eyes.

    PubMed

    Clark, Sarah; Antell, Alexandra; Kaufman, Kimberly

    2015-02-01

    Ezogabine is an antiepileptic medication approved in June 2011 by the US Food and Drug Administration (FDA) as an adjunctive treatment for partial seizures. Minimal drug interactions and a novel mechanism of action made ezogabine an appealing new treatment option. However, adverse effects reported during clinical trials and following drug approval have been alarming. A Risk Evaluation Mitigation Strategy (REMS) program has been established for urinary retention. A safety alert was published in April 2013 warning ezogabine may cause retinal pigment abnormalities and/or blue-gray discoloration, most notably on or near the lips, nail beds, sclera and conjunctiva with long-term use. In October 2013, the FDA announced a formal label change to ezogabine to include a black boxed warning emphasizing the previously reported warnings of eye and skin discoloration and permanent vision changes. Given the unknown nature of the pathophysiology, consequences and potential for reversibility of these effects, GlaxoSmithKline and the FDA have published recommendations for patients currently receiving ezogabine. Further data from published case reports and long-term safety trials in the future may lend additional insight into these concerning effects.

  4. Pretreatment of pigments to prepare liquids for enteric coating.

    PubMed

    Bölcskei, E; Bajdik, J; Müller, J; Knop, K; Kleinebudde, P; Pintye-Hódi, K

    2008-07-01

    Film coating fluids commonly contain different pigments. The objective of this work was a study of the distribution of these particles in the coating film. Different pretreatment forms (pigment suspension, pigment paste and untreated pigments) were applied. They were incorporated into a Eudragit L 30 D-55 dispersion. The surface roughness and the mechanical properties of the free films indicated, that the most homogeneous film was obtained with the pigment paste. The homogeneity of the film was investigated by mechanical testing. The protective effect of the coating did not vary with the application of pigments in different forms, but the appearance of the coated tablets underwent a considerable change.

  5. 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

  6. Sarcomatoid carcinoma arising in the congenital pigmented nevus after treatment with carbon dioxide snow freezing method.

    PubMed

    Nakajima, Rina; Komine, Mayumi; Miyamoto, Yukiko; Fusumae, Takayuki; Fujita, Yurika; Maekawa, Takeo; Murata, Satoru; Fukushima, Noriyoshi; Ohtsuki, Mamitaro

    2015-11-01

    We report a case of sarcomatoid carcinoma of the skin in a 63-year-old man who was treated with the carbon dioxide snow freezing method for a huge congenital pigmented nevus that extended from the right upper extremity to the right trunk during childhood. He had an exophytic red tumor on the nevus in the right upper extremity that grew slowly for 4 years and rapidly recently. Histological and immunohistochemical studies revealed both epithelial and mesenchymal malignancy in the same tumor. The epithelial component was composed of basaloid cells forming multiple nests with peripheral palisading, positive for keratins and BerEP4, implying basal cell carcinoma. The mesenchymal component was composed of spindle-shaped cells negative for keratins and positive for vimentin, suggesting sarcoma. This is, to our knowledge, the first report of sarcomatoid carcinoma arising in the primary pigmented nevus that had been treated by the carbon dioxide snow freezing method.

  7. Melanoma induction by ultraviolet A but not ultraviolet B radiation requires melanin pigment.

    PubMed

    Noonan, Frances P; Zaidi, M Raza; Wolnicka-Glubisz, Agnieszka; Anver, Miriam R; Bahn, Jesse; Wielgus, Albert; Cadet, Jean; Douki, Thierry; Mouret, Stephane; Tucker, Margaret A; Popratiloff, Anastas; Merlino, Glenn; De Fabo, Edward C

    2012-06-06

    Malignant melanoma of the skin (CMM) is associated with ultraviolet radiation exposure, but the mechanisms and even the wavelengths responsible are unclear. Here we use a mammalian model to investigate melanoma formed in response to precise spectrally defined ultraviolet wavelengths and biologically relevant doses. We show that melanoma induction by ultraviolet A (320-400 nm) requires the presence of melanin pigment and is associated with oxidative DNA damage within melanocytes. In contrast, ultraviolet B radiation (280-320 nm) initiates melanoma in a pigment-independent manner associated with direct ultraviolet B DNA damage. Thus, we identified two ultraviolet wavelength-dependent pathways for the induction of CMM and describe an unexpected and significant role for melanin within the melanocyte in melanomagenesis.

  8. Olanzapine-Induced Reversible Pellagroid Skin Lesion.

    PubMed

    Singh, Lokesh K; Sahu, Manoj; Praharaj, Samir K

    2015-01-01

    Adverse cutaneous reactions are frequently reported to occur with the use of psychotropic medications, which may lead to poor drug compliance. As compared to other groups of psychotropic medication, antipsychotics, both typical and atypical, are less likely to cause adverse cutaneous reactions. The most frequent cutaneous adverse reactions associated with antipsychotics include fixed drug eruptions, exanthematous eruptions, photosensitivity reactions and altered skin pigmentation. Most of these commonly seen cutaneous adverse reactions are benign and easily treatable. Rarely, severe cutaneous adverse reactions such as erythema multiforme, Steven-Johnson syndrome are toxic epidermal necrolysis and have also been associated with antipsychotics. Olanzapine is one of the most commonly prescribed atypical antipsychotic with metabolic complications as most common adverse effects. Dermatological reactions are rarely observed with olanzapine. We report occurrence of pellagroid skin lesions over exposed areas of upper limbs with olanzapine that resolved completely after its discontinuation.

  9. 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.

  10. Pigments which reflect infrared radiation from fire

    DOEpatents

    Berdahl, P.H.

    1998-09-22

    Conventional paints transmit or absorb most of the intense infrared (IR) radiation emitted by fire, causing them to contribute to the spread of fire. The present invention comprises a fire retardant paint additive that reflects the thermal IR radiation emitted by fire in the 1 to 20 micrometer ({micro}m) wavelength range. The important spectral ranges for fire control are typically about 1 to about 8 {micro}m or, for cool smoky fires, about 2 {micro}m to about 16 {micro}m. The improved inventive coatings reflect adverse electromagnetic energy and slow the spread of fire. Specific IR reflective pigments include titanium dioxide (rutile) and red iron oxide pigments with diameters of about 1 {micro}m to about 2 {micro}m and thin leafing aluminum flake pigments. 4 figs.

  11. Pigments which reflect infrared radiation from fire

    DOEpatents

    Berdahl, Paul H.

    1998-01-01

    Conventional paints transmit or absorb most of the intense infrared (IR) radiation emitted by fire, causing them to contribute to the spread of fire. The present invention comprises a fire retardant paint additive that reflects the thermal IR radiation emitted by fire in the 1 to 20 micrometer (.mu.m) wavelength range. The important spectral ranges for fire control are typically about 1 to about 8 .mu.m or, for cool smoky fires, about 2 .mu.m to about 16 .mu.m. The improved inventive coatings reflect adverse electromagnetic energy and slow the spread of fire. Specific IR reflective pigments include titanium dioxide (rutile) and red iron oxide pigments with diameters of about 1 .mu.m to about 2 .mu.m and thin leafing aluminum flake pigments.

  12. Skin to skin care:heat balance.

    PubMed Central

    Karlsson, H

    1996-01-01

    Skin to skin care has been practised in primitive and high technology cultures for body temperature preservation in neonates. Regional skin temperature and heat flow was measured in moderately hypothermic term neonates to quantitate the heat transfer occurring during one hour of skin to skin care. Nine healthy newborns with a mean rectal temperature of 36.3 degrees C were placed skin to skin on their mothers' chests. The mean (SD) rectal temperature increased by 0.7 (0.4) degrees C to 37.0 degrees C. The heat loss was high (70 Wm-2) from the unprotected skin of the head to the surrounding air. Minute heat losses occurred from covered areas; and heat was initially gained from areas in contact with the mother's skin. The total dry heat loss during skin to skin care corresponded to heat loss during incubator care at 32-32.5 degrees C. The reduced heat loss, and to a minor extent, the initial heat flux from the mothers allowed heat to be conserved, leading to rewarming. PMID:8949698

  13. Tattoo ink nanoparticles in skin tissue and fibroblasts

    PubMed Central

    Twigg, Peter C; Baker, Richard; Tobin, Desmond J

    2015-01-01

    Summary Tattooing has long been practised in various societies all around the world and is becoming increasingly common and widespread in the West. Tattoo ink suspensions unquestionably contain pigments composed of nanoparticles, i.e., particles of sub-100 nm dimensions. It is widely acknowledged that nanoparticles have higher levels of chemical activity than their larger particle equivalents. However, assessment of the toxicity of tattoo inks has been the subject of little research and ink manufacturers are not obliged to disclose the exact composition of their products. This study examines tattoo ink particles in two fundamental skin components at the nanometre level. We use atomic force microscopy and light microscopy to examine cryosections of tattooed skin, exploring the collagen fibril networks in the dermis that contain ink nanoparticles. Further, we culture fibroblasts in diluted tattoo ink to explore both the immediate impact of ink pigment on cell viability and also to observe the interaction between particles and the cells. PMID:26171294

  14. Tattoo ink nanoparticles in skin tissue and fibroblasts.

    PubMed

    Grant, Colin A; Twigg, Peter C; Baker, Richard; Tobin, Desmond J

    2015-01-01

    Tattooing has long been practised in various societies all around the world and is becoming increasingly common and widespread in the West. Tattoo ink suspensions unquestionably contain pigments composed of nanoparticles, i.e., particles of sub-100 nm dimensions. It is widely acknowledged that nanoparticles have higher levels of chemical activity than their larger particle equivalents. However, assessment of the toxicity of tattoo inks has been the subject of little research and ink manufacturers are not obliged to disclose the exact composition of their products. This study examines tattoo ink particles in two fundamental skin components at the nanometre level. We use atomic force microscopy and light microscopy to examine cryosections of tattooed skin, exploring the collagen fibril networks in the dermis that contain ink nanoparticles. Further, we culture fibroblasts in diluted tattoo ink to explore both the immediate impact of ink pigment on cell viability and also to observe the interaction between particles and the cells.

  15. Protective responses to sublytic complement in the retinal pigment epithelium

    PubMed Central

    Tan, Li Xuan; Toops, Kimberly A.; Lakkaraju, Aparna

    2016-01-01

    The retinal pigment epithelium (RPE) is a key site of injury in inherited and age-related macular degenerations. Abnormal activation of the complement system is a feature of these blinding diseases, yet how the RPE combats complement attack is poorly understood. The complement cascade terminates in the cell-surface assembly of membrane attack complexes (MACs), which promote inflammation by causing aberrant signal transduction. Here, we investigated mechanisms crucial for limiting MAC assembly and preserving cellular integrity in the RPE and asked how these are compromised in models of macular degeneration. Using polarized primary RPE and the pigmented Abca4−/− Stargardt disease mouse model, we provide evidence for two protective responses occurring within minutes of complement attack, which are essential for maintaining mitochondrial health in the RPE. First, accelerated recycling of the membrane-bound complement regulator CD59 to the RPE cell surface inhibits MAC formation. Second, fusion of lysosomes with the RPE plasma membrane immediately after complement attack limits sustained elevations in intracellular calcium and prevents mitochondrial injury. Cholesterol accumulation in the RPE, induced by vitamin A dimers or oxidized LDL, inhibits these defense mechanisms by activating acid sphingomyelinase (ASMase), which increases tubulin acetylation and derails organelle traffic. Defective CD59 recycling and lysosome exocytosis after complement attack lead to mitochondrial fragmentation and oxidative stress in the RPE. Drugs that stimulate cholesterol efflux or inhibit ASMase restore both these critical safeguards in the RPE and avert complement-induced mitochondrial injury in vitro and in Abca4−/− mice, indicating that they could be effective therapeutic approaches for macular degenerations. PMID:27432952

  16. Cross-Linked Fluorescent Supramolecular Nanoparticles as Finite Tattoo Pigments with Controllable Intradermal Retention Times.

    PubMed

    Choi, Jin-Sil; Zhu, Yazhen; Li, Hongsheng; Peyda, Parham; Nguyen, Thuy Tien; Shen, Mo Yuan; Yang, Yang Michael; Zhu, Jingyi; Liu, Mei; Lee, Mandy M; Sun, Shih-Sheng; Yang, Yang; Yu, Hsiao-Hua; Chen, Kai; Chuang, Gary S; Tseng, Hsian-Rong

    2017-01-24

    Tattooing has been utilized by the medical community for precisely demarcating anatomic landmarks. This practice is especially important for identifying biopsy sites of nonmelanoma skin cancer (NMSC) due to the long interval (i.e., up to 3 months) between the initial diagnostic biopsy and surgical treatment. Commercially available tattoo pigments possess several issues, which include causing poor cosmesis, being mistaken for a melanocytic lesion, requiring additional removal procedures when no longer desired, and potentially inducing inflammatory responses. The ideal tattoo pigment for labeling of skin biopsy sites for NMSC requires (i) invisibility under ambient light, (ii) fluorescence under a selective light source, (iii) a finite intradermal retention time (ca. 3 months), and (iv) biocompatibility. Herein, we introduce cross-linked fluorescent supramolecular nanoparticles (c-FSNPs) as a "finite tattoo" pigment, with optimized photophysical properties and intradermal retention time to achieve successful in vivo finite tattooing. Fluorescent supramolecular nanoparticles encapsulate a fluorescent conjugated polymer, poly[5-methoxy-2-(3-sulfopropoxy)-1,4-phenylenevinylene] (MPS-PPV), into a core via a supramolecular synthetic approach. FSNPs which possess fluorescent properties superior to those of the free MPS-PPV are obtained through a combinatorial screening process. Covalent cross-linking of FSNPs results in micrometer-sized c-FSNPs, which exhibit a size-dependent intradermal retention. The 1456 nm sized c-FSNPs display an ideal intradermal retention time (ca. 3 months) for NMSC lesion labeling, as observed in an in vivo tattoo study. In addition, the c-FSNPs induce undetectable inflammatory responses after tattooing. We believe that the c-FSNPs can serve as a "finite tattoo" pigment to label potential malignant NMSC lesions.

  17. Green pigments of the Pompeian artists' palette

    NASA Astrophysics Data System (ADS)

    Aliatis, Irene; Bersani, Danilo; Campani, Elisa; Casoli, Antonella; Lottici, Pier Paolo; Mantovan, Silvia; Marino, Iari-Gabriel; Ospitali, Francesca

    2009-08-01

    Green colored samples on wall paintings and green powder from a pigment pot found in Pompeii area are investigated by micro-Raman, FT-IR and, for one sample, SEM-EDX. To obtain the green color, green earths and malachite were used, together with mixture of Egyptian blue and yellow ochre. The mineralogical identification of the green earths has been attempted through the comparison of the vibrational features, discriminating between celadonite and glauconite spectra. Traces of a modern synthetic pigment containing copper phthalocyanine were found in a fresco fragment.

  18. RISK ASSESSMENT FOR THE DYE AND PIGMENT ...

    EPA Pesticide Factsheets

    This risk assessment calculates the maximum loadings of constituents found in dyes and pigment industries waste streams which can be disposed in different types of waste management units without causing health benchmarks to be exceeded at plausible receptor locations. The assessment focuses on potential risks from volatilization and leaching to groundwater of constituents disposed in surface impoundments and landfills with either clay liners or composite liners. This product will be used by EPA decision makers to assist in determining whether certain waste streams generated by the dyes and pigments industries should be designated as hazardous.

  19. Abnormal pressure in hydrocarbon environments

    USGS Publications Warehouse

    Law, B.E.; Spencer, C.W.

    1998-01-01

    Abnormal pressures, pressures above or below hydrostatic pressures, occur on all continents in a wide range of geological conditions. According to a survey of published literature on abnormal pressures, compaction disequilibrium and hydrocarbon generation are the two most commonly cited causes of abnormally high pressure in petroleum provinces. In young (Tertiary) deltaic sequences, compaction disequilibrium is the dominant cause of abnormal pressure. In older (pre-Tertiary) lithified rocks, hydrocarbon generation, aquathermal expansion, and tectonics are most often cited as the causes of abnormal pressure. The association of abnormal pressures with hydrocarbon accumulations is statistically significant. Within abnormally pressured reservoirs, empirical evidence indicates that the bulk of economically recoverable oil and gas occurs in reservoirs with pressure gradients less than 0.75 psi/ft (17.4 kPa/m) and there is very little production potential from reservoirs that exceed 0.85 psi/ft (19.6 kPa/m). Abnormally pressured rocks are also commonly associated with unconventional gas accumulations where the pressuring phase is gas of either a thermal or microbial origin. In underpressured, thermally mature rocks, the affected reservoirs have most often experienced a significant cooling history and probably evolved from an originally overpressured system.

  20. Systemic abnormalities in liver disease

    PubMed Central

    Minemura, Masami; Tajiri, Kazuto; Shimizu, Yukihiro

    2009-01-01

    Systemic abnormalities often occur in patients with liver disease. In particular, cardiopulmonary or renal diseases accompanied by advanced liver disease can be serious and may determine the quality of life and prognosis of patients. Therefore, both hepatologists and non-hepatologists should pay attention to such abnormalities in the management of patients with liver diseases. PMID:19554648