Science.gov

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

    ... a Concussion in Past Year AHA: Take Your Dog to Work -- And Reap the Health Benefits Could ... drugs, procedures, news and more, written in everyday language. Tap to switch to the Professional ... a Skin Cancer Body Check (Video) Pubic Lice (Video) Skin Cancer Additional ...

  3. [Normal and abnormal skin color].

    PubMed

    Ortonne, J-P

    2012-11-01

    The varieties of normal skin color in humans range from people of "no color" (pale white) to "people of color" (light brown, dark brown, and black). Skin color is a blend resulting from the skin chromophores red (oxyhaemoglobin), blue (deoxygenated haemoglobin), yellow-orange (carotene, an exogenous pigment), and brown (melanin). Melanin, however, is the major component of skin color ; it is the presence or absence of melanin in the melanosomes in melanocytes and melanin in keratinocytes that is responsible for epidermal pigmentation, and the presence of melanin in macrophages or melanocytes in the dermis that is responsible for dermal pigmentation. Two groups of pigmentary disorders are commonly distinguished: the disorders of the quantitative and qualitative distribution of normal pigment and the abnormal presence of exogenous or endogenous pigments in the skin. The first group includes hyperpigmentations, which clinically manifest by darkening of the skin color, and leukodermia, which is characterized by lightening of the skin. Hypermelanosis corresponds to an overload of melanin or an abnormal distribution of melanin in the skin. Depending on the color, melanodermia (brown/black) and ceruloderma (blue/grey) are distinguished. Melanodermia correspond to epidermal hypermelanocytosis (an increased number of melanocytes) or epidermal hypermelanosis (an increase in the quantity of melanin in the epidermis with no modification of the number of melanocytes). Ceruloderma correspond to dermal hypermelanocytosis (abnormal presence in the dermis of cells synthesizing melanins) ; leakage in the dermis of epidermal melanin also exists, a form of dermal hypermelanosis called pigmentary incontinence. Finally, dyschromia can be related to the abnormal presence in the skin of a pigment of exogenous or endogenous origin. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  4. Skin Color and Pigmentation in Ethnic Skin.

    PubMed

    Visscher, Marty O

    2017-02-01

    Skin coloration is highly diverse, partly due to the presence of pigmentation. Color variation is related to the extent of ultraviolet radiation exposure, as well as other factors. Inherent skin coloration arises from differences in basal epidermal melanin amount and type. Skin color is influenced by both the quantity and distribution of melanocytes. The effectiveness of inherent pigmentation for protecting living cells also varies. This article discusses skin color, pigmentation, and ethnicity in relation to clinical practice. Color perception, skin typing/classification, and quantitation of pigmentation are reviewed in relation to ethnicity, environmental stresses/irritants, and potential treatment effects. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Skin - abnormally dark or light

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003242.htm Abnormally dark or light skin To use the sharing features ... The bronze color can range from light to dark (in fair-skinned people) with the degree of ...

  6. Skin cancer, basal cell carcinoma - pigmented (image)

    MedlinePlus

    ... cancer appears as a 2 to 3 centimeter skin spot. The tissue has become destroyed (forming an atrophic plaque). There is a brownish color because of increased skin pigment (hyperpigmentation) and a slightly elevated, rolled, pearl- ...

  7. Physiological factors that regulate skin pigmentation

    PubMed Central

    Yamaguchi, Yuji; Hearing, Vincent J.

    2009-01-01

    More than 150 genes have been identified that affect skin color either directly or indirectly, and we review current understanding of physiological factors that regulate skin pigmentation. We focus on melanosome biogenesis, transport and transfer, melanogenic regulators in melanocytes and factors derived from keratinocytes, fibroblasts, endothelial cells, hormones, inflammatory cells and nerves. Enzymatic components of melanosomes include tyrosinase, tyrosinase-related protein 1 and dopachrome tautomerase, which depend on the functions of OA1, P, MATP, ATP7A and BLOC-1 to synthesize eumelanins and pheomelanins. The main structural component of melanosomes is Pmel17/gp100/Silv, whose sorting involves adaptor protein 1A (AP1A), AP1B, AP2 and spectrin, as well as a chaperone-like component, MART-1. During their maturation, melanosomes move from the perinuclear area toward the plasma membrane. Microtubules, dynein, kinesin, actin filaments, Rab27a, melanophilin, myosin Va and Slp2-a are involved in melanosome transport. Foxn1 and p53 up-regulate skin pigmentation via bFGF and POMC derivatives including α-MSH and ACTH, respectively. Other critical factors that affect skin pigmentation include MC1R, CREB, ASP, MITF, PAX3, SOX9/10, LEF-1/TCF, PAR-2, DKK1, SCF, HGF, GM-CSF, endothelin-1, prostaglandins, leukotrienes, thromboxanes, neurotrophins and neuropeptides. UV radiation up-regulates most factors that increase melanogenesis. Further studies will elucidate the currently unknown functions of many other pigment genes/proteins. PMID:19449448

  8. Laypersons' perceptual discrimination of pigmented skin lesions.

    PubMed

    Bränström, Richard; Hedblad, Mari-Anne; Krakau, Ingvar; Ullén, Henrik

    2002-05-01

    Most cutaneous malignant melanomas of the skin are visible and should, at least in theory, be possible to detect with the naked eye. This study was conducted to learn more about laypersons' ability to discriminate between benign pigmented lesions and malignant ones. Four groups of laypersons (n = 120) were asked to evaluate pictures of different types of pigmented skin lesions, before and after they received information about the ABCD (asymmetry, border irregularity, color variegation, and diameter greater than 6 mm) criteria, with respect to the necessity of action. The respondents made adequate assessments of melanomas but overestimated the danger of benign pigmented skin lesions. Information about the ABCD criteria enhanced their ability to make adequate assessments. People seem to make adequate decisions concerning how to act if they have a melanoma. On the other hand, common moles and dysplastic nevi were harder to discriminate. Providing information to the public about the features of melanomas, in accordance with the ABCD criteria, might help laypersons in their perceptual discrimination of skin lesions.

  9. Inhibitory effect of corn silk on skin pigmentation.

    PubMed

    Choi, Sang Yoon; Lee, Yeonmi; Kim, Sung Soo; Ju, Hyun Min; Baek, Ji Hwoon; Park, Chul-Soo; Lee, Dong-Hyuk

    2014-03-03

    In this study, the inhibitory effect of corn silk on melanin production was evaluated. This study was performed to investigate the inhibitory effect of corn silk on melanin production in Melan-A cells by measuring melanin production and protein expression. The corn silk extract applied on Melan-A cells at a concentration of 100 ppm decreased melanin production by 37.2% without cytotoxicity. This was a better result than arbutin, a positive whitening agent, which exhibited a 26.8% melanin production inhibitory effect at the same concentration. The corn silk extract did not suppress tyrosinase activity but greatly reduced the expression of tyrosinase in Melan-A cells. In addition, corn silk extract was applied to the human face with hyperpigmentation, and skin color was measured to examine the degree of skin pigment reduction. The application of corn silk extract on faces with hyperpigmentation significantly reduced skin pigmentation without abnormal reactions. Based on the results above, corn silk has good prospects for use as a material for suppressing skin pigmentation.

  10. Physiological factors that regulate skin pigmentation.

    PubMed

    Yamaguchi, Yuji; Hearing, Vincent J

    2009-01-01

    More than 150 genes have been identified that affect skin color either directly or indirectly, and we review current understanding of physiological factors that regulate skin pigmentation. We focus on melanosome biogenesis, transport and transfer, melanogenic regulators in melanocytes, and factors derived from keratinocytes, fibroblasts, endothelial cells, hormones, inflammatory cells, and nerves. Enzymatic components of melanosomes include tyrosinase, tyrosinase-related protein 1, and dopachrome tautomerase, which depend on the functions of OA1, P, MATP, ATP7A, and BLOC-1 to synthesize eumelanins and pheomelanins. The main structural component of melanosomes is Pmel17/gp100/Silv, whose sorting involves adaptor protein 1A (AP1A), AP1B, AP2, and spectrin, as well as a chaperone-like component, MART-1. During their maturation, melanosomes move from the perinuclear area toward the plasma membrane. Microtubules, dynein, kinesin, actin filaments, Rab27a, melanophilin, myosin Va, and Slp2-a are involved in melanosome transport. Foxn1 and p53 up-regulate skin pigmentation via bFGF and POMC derivatives including alpha-MSH and ACTH, respectively. Other critical factors that affect skin pigmentation include MC1R, CREB, ASP, MITF, PAX3, SOX9/10, LEF-1/TCF, PAR-2, DKK1, SCF, HGF, GM-CSF, endothelin-1, prostaglandins, leukotrienes, thromboxanes, neurotrophins, and neuropeptides. UV radiation up-regulates most factors that increase melanogenesis. Further studies will elucidate the currently unknown functions of many other pigment genes/proteins. (c) 2009 International Union of Biochemistry and Molecular Biology, Inc.

  11. Pigment network-based skin cancer detection.

    PubMed

    Alfed, Naser; Khelifi, Fouad; Bouridane, Ahmed; Seker, Huseyin

    2015-08-01

    Diagnosing skin cancer in its early stages is a challenging task for dermatologists given the fact that the chance for a patient's survival is higher and hence the process of analyzing skin images and making decisions should be time efficient. Therefore, diagnosing the disease using automated and computerized systems has nowadays become essential. This paper proposes an efficient system for skin cancer detection on dermoscopic images. It has been shown that the statistical characteristics of the pigment network, extracted from the dermoscopic image, could be used as efficient discriminating features for cancer detection. The proposed system has been assessed on a dataset of 200 dermoscopic images of the `Hospital Pedro Hispano' [1] and the results of cross-validation have shown high detection accuracy.

  12. 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

  13. Raman spectra of pigmented skin conditions

    NASA Astrophysics Data System (ADS)

    Bitar, Renata; Moreno, Marcelo; Oliveira, Andréa; Cartaxo, Sidney; Martinho, Herculano; Espírito Santo, Ana Maria do; Santos, Ivan Dunshee; Ferreira, Lydia Massako; Martin, Airton

    2007-02-01

    Melanoma is the most aggressive skin cancer and is invariably fatal if left untreated. Melanoma removal at early stages is almost always curative and therefore early detection is essential. Removal of every pigmented lesion is unacceptable for the patient, especially in the case of multiple skin lesions or lesions localized in cosmetically important parts of the body such as the face because of risk of scarring. The development of a technique to detect these changes in a noninvasive way is therefore crucial for melanoma detection. In this study, we have used FT-Raman Spectroscopy to investigate through PCA analysis the alterations in the molecular structure of 90 skin spectra, being 30 Pigmented Nevi, 30 Primary Melanoma, and 30 Metastasis, for 6 patients. For projection of data, the scores (Principal Components) PC1 to PC3 were calculated. PC1 versus PC3 for the 800 to 1800 cm -1 spectral region. PC1 versus PC2 for the 1200 to 1400 cm -1 spectral region. In both analysis, we could differentiate the three different types of tissues.

  14. Pigmentation in African American skin decreases with skin aging.

    PubMed

    Chien, Anna L; Suh, Jean; Cesar, Sabrina Sisto Alessi; Fischer, Alexander H; Cheng, Nancy; Poon, Flora; Rainer, Barbara; Leung, Sherry; Martin, Jo; Okoye, Ginette A; Kang, Sewon

    2016-10-01

    Tristimulus colorimetry, which uses the Commission Internationale de l'Eclairage L*a*b* model to quantify color, has previously been used to analyze pigmentation and erythema in human skin; however, colorimetry of African American skin is not well characterized. We sought to analyze skin color patterns in African Americans and compare them with those of Caucasians. Colorimetry readings of the sun-protected buttock and sun-exposed back of forearm were taken from 40 Caucasian and 43 African American participants from March 2011 through August 2015. African American participants also completed a lifestyle questionnaire. Correlation coefficients, paired t tests, and multivariable linear regression analyses were used for statistical comparisons. Forearm skin was lighter in African Americans ages 65 years and older versus 18 to 30 years (P = .02) but darker in Caucasians ages 65 years or older versus 18 to 30 years (P = .03). In African Americans ages 18 to 30 years, the buttock was darker than the forearm (P < .001), whereas in Caucasians the buttock was lighter than the forearm (P < .001). A lighter forearm than buttock was correlated with supplement use, smoking (ages 18-30 years), and less recreational sun exposure (ages ≥65 years) in African Americans. Our study was limited by the sample size and focal geographic source. Pigmentation patterns regarding sun-protected and sun-exposed areas in African Americans may differ from that of Caucasians, suggesting that other factors may contribute to skin pigmentation in African Americans. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  15. 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

  16. Fluorescence and reflectance properties of hemoglobin-pigmented skin disorders

    NASA Astrophysics Data System (ADS)

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

    2007-06-01

    There has been growing interest in clinical application of laser-induced autofluorescence (LIAF) and reflectance spectroscopy (RS) to differentiate disease from normal surrounding tissue, including skin pathologies. Pigmented cutaneous lesions diagnosis plays important role in clinical practice, as malignant melanoma, which is characterized with greatest mortality from all skin cancer types, must be carefully discriminated form other colorized pathologies. The goals of this work were investigation of cutaneous hemoglobin-pigmented lesions (heamangioma, angiokeratoma, and fibroma) by the methods of LIAFS and RS. Spectra from healthy skin areas near to the lesion were detected to be used posteriori in analysis. Fluorescence and reflectance of cutaneous hemoglobin-pigmented lesions are used to develop criterion for differentiation from other pigmented pathologies. Origins of the spectral features obtained are discussed and determination of lesion types is achieved using selected spectral features. The spectral results, obtained were used to develop multispectral diagnostic algorithms based on the most prominent spectral features from the fluorescence and reflectance spectra of the lesions investigated. In comparison between normal skin and different cutaneous lesion types and between lesion types themselves sensitivities and specificities higher than 90 % were achieved. These results show a perspective possibility to differentiate hemoglobin-pigmented lesions from other pigmented pathologies using non-invasive and real time discrimination procedure.

  17. Loci associated with skin pigmentation identified in African populations

    PubMed Central

    Crawford, Nicholas G.; Kelly, Derek E.; Hansen, Matthew E. B.; Beltrame, Marcia H.; Fan, Shaohua; Bowman, Shanna L.; Jewett, Ethan; Ranciaro, Alessia; Thompson, Simon; Lo, Yancy; Pfeifer, Susanne P.; Jensen, Jeffrey D.; Campbell, Michael C.; Beggs, William; Hormozdiari, Farhad; Mpoloka, Sununguko Wata; Mokone, Gaonyadiwe George; Nyambo, Thomas; Meskel, Dawit Wolde; Belay, Gurja; Haut, Jake; Rothschild, Harriet; Zon, Leonard; Zhou, Yi; Kovacs, Michael A.; Xu, Mai; Zhang, Tongwu; Bishop, Kevin; Sinclair, Jason; Rivas, Cecilia; Elliot, Eugene; Choi, Jiyeon; Li, Shengchao A.; Hicks, Belynda; Burgess, Shawn; Abnet, Christian; Watkins-Chow, Dawn E.; Oceana, Elena; Song, Yun S.; Eskin, Eleazar; Brown, Kevin M.; Marks, Michael S.; Loftus, Stacie K.; Pavan, William J.; Yeager, Meredith; Chanock, Stephen; Tishkoff, Sarah

    2017-01-01

    Despite the wide range of skin pigmentation in humans, little is known about its genetic basis in global populations. Examining ethnically diverse African genomes, we identify variants in or near SLC24A5, MFSD12, DDB1, TMEM138, OCA2 and HERC2 that are significantly associated with skin pigmentation. Genetic evidence indicates that the light pigmentation variant at SLC24A5 was introduced into East Africa by gene flow from non-Africans. At all other loci, variants associated with dark pigmentation in Africans are identical by descent in southern Asian and Australo-Melanesian populations. Functional analyses indicate that MFSD12 encodes a lysosomal protein that affects melanogenesis in zebrafish and mice, and that mutations in melanocyte-specific regulatory regions near DDB1/TMEM138 correlate with expression of UV response genes under selection in Eurasians. PMID:29025994

  18. UV-B affects the immune system and promotes nuclear abnormalities in pigmented and non-pigmented bullfrog tadpoles.

    PubMed

    Franco-Belussi, Lilian; Fanali, Lara Zácari; De Oliveira, Classius

    2018-03-01

    Ultra-Violet (UV) radiation is a stressor of the immune system and causes DNA damage. Leukocytes can change in response to environmental changes in anurans, making them an important biomarker of stressful situations. The initial barrier against UV in ectothermic animals is melanin-containing cells in skin and in their internal organs. Here, we tested the effects of UV exposure on immune cells and DNA integrity in pigmented and non-pigmented tadpoles of Lithobates catesbeianus. We used an inflammation model with lipopolysaccharide (LPS) of Escherichia coli to test synergic effects of UV and LPS. We tested the following hypotheses: 1) DNA damage caused by UV will be more pronounced in non-pigmented than in pigmented animals; 2) LPS increases leukocytes in both pigmented and non-pigmented animals by systemic inflammation; 3) The combined LPS and UV exposure will decrease the number of leukocytes. We found that the frequency of immune cells differed between pigmented and non-pigmented tadpoles. UV exposure increased mast cells and DNA damage in erythrocytes in both pigmented and non-pigmented tadpoles, while leukocytes decreased after UV exposure. Non-pigmented tadpoles experienced DNA damage and a lower lymphocyte count earlier than pigmented tadpoles. UV altered immune cells likely as a consequence of local and systemic inflammation. These alterations were less severe in pigmented than in non-pigmented animals. UV and LPS increased internal melanin in pigmented tadpoles, which were correlated with DNA damage and leukocytes. Here, we described for the first time the effects of UV and LPS in immune cells of pigmented and non-pigmented tadpoles. In addition, we demonstrated that internal melanin in tadpoles help in these defenses, since leukocyte responses were faster in non-pigmented animals, supporting the hypothesis that melanin is involved in the initial innate immune response. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. 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

  20. Selected gene polymorphisms effect on skin and hair pigmentation in Polish children at the prepubertal age.

    PubMed

    Sitek, Aneta; Rosset, Iwona; Żądzińska, Elżbieta; Siewierska-Górska, Anna; Pietrowska, Edyta; Strapagiel, Dominik

    2016-11-01

    Background : Human pigmentation, similarly as many other biological features, changes in the course of post-natal ontogenesis, while in case of hair, pigmentation changes are more distinctive than in the skin or the iris. It is therefore extremely important to identify the genes, involved in the constitution of human pigmentation features at various stages of ontogenesis. Results of this type of analyses are of high practical significance in forensic study because they enable to create mathematical tools, allowing for prediction of the pigmentation phenotype, based on DNA studies. Aim : The objective of the investigation was finding out whether the genes, associated with pigmentation of adult subjects, differentiated in any way the newly forming pigmentation phenotype in Polish prepubertal children. Material and methods : The study encompassed Polish children, aged 7 to 10 years, without any abnormalities in skin or hair pigmentation. A total of 245 children were examined. Constitutive skin pigmentation according to skin melanin index (SMI) was evaluated, using a dermaspectrometer, and classified into three groups based on the reference values of 25 and 75 percentile for Polish children. Hair colors were evaluated by means of the descriptive Fischer-Saller scale and classified by a division of color variants (as accepted in that scale) (light blonde, blonde, dark blonde, brown and dark brown). In saliva samples, collected from the children, five (5) single nucleotide polymorphisms were identified: SNPs : rs1800401 ( OCA2 -15q11.2-q12), rs35264875 ( TPCN2 -11q13.3), rs16891982 ( SLC45A2 -5p13.2), rs12913832 ( HERC2 -15q13) and rs1805007 ( MC1R -16q24.3). An association between each allele of verified genotype and skin and hair color phenotypes was assessed, using the z-statistic and associated p -value. The quality of classifiers was evaluated by 10-fold stratified cross-validation and was characterized by the area under the receiver operating characteristic curve

  1. [Indices of pigment formation in complex cytomorphological research on human pigmented skin neoplasms].

    PubMed

    Naleskina, L A

    1985-01-01

    Analysis of the topography peculiarities and distribution of oxidized melanine and its precursors (DOPA-oxide activity and catecholamine) in pigment nevuses and malignant melanomas of skin shows that the studied peculiarities are a complex of intersupplementary markers of melanine formation, correlate with the quality and the degree of proliferative process expression in tumours of this genesis and may be used for their malignancy rating.

  2. Proof-of-concept: 3D bioprinting of pigmented human skin constructs.

    PubMed

    Ng, Wei Long; Qi, Jovina Tan Zhi; Yeong, Wai Yee; Naing, May Win

    2018-01-23

    Three-dimensional (3D) pigmented human skin constructs have been fabricated using a 3D bioprinting approach. The 3D pigmented human skin constructs are obtained from using three different types of skin cells (keratinocytes, melanocytes and fibroblasts from three different skin donors) and they exhibit similar constitutive pigmentation (pale pigmentation) as the skin donors. A two-step drop-on-demand bioprinting strategy facilitates the deposition of cell droplets to emulate the epidermal melanin units (pre-defined patterning of keratinocytes and melanocytes at the desired positions) and manipulation of the microenvironment to fabricate 3D biomimetic hierarchical porous structures found in native skin tissue. The 3D bioprinted pigmented skin constructs are compared to the pigmented skin constructs fabricated by conventional a manual-casting approach; in-depth characterization of both the 3D pigmented skin constructs has indicated that the 3D bioprinted skin constructs have a higher degree of resemblance to native skin tissue in term of the presence of well-developed stratified epidermal layers and the presence of a continuous layer of basement membrane proteins as compared to the manually-cast samples. The 3D bioprinting approach facilitates the development of 3D in vitro pigmented human skin constructs for potential toxicology testing and fundamental cell biology research.

  3. Application of principal component analysis to multispectral imaging data for evaluation of pigmented skin lesions

    NASA Astrophysics Data System (ADS)

    Jakovels, Dainis; Lihacova, Ilze; Kuzmina, Ilona; Spigulis, Janis

    2013-11-01

    Non-invasive and fast primary diagnostics of pigmented skin lesions is required due to frequent incidence of skin cancer - melanoma. Diagnostic potential of principal component analysis (PCA) for distant skin melanoma recognition is discussed. Processing of the measured clinical multi-spectral images (31 melanomas and 94 nonmalignant pigmented lesions) in the wavelength range of 450-950 nm by means of PCA resulted in 87 % sensitivity and 78 % specificity for separation between malignant melanomas and pigmented nevi.

  4. Analysis of major elements in pigmented melanocytic chicken skin using laser-induced breakdown spectroscopy.

    PubMed

    Lee, Jong Jin; Moon, Youngmin; Han, Jung Hyun; Jeong, Sungho

    2017-04-01

    The concentration difference of major elements in melanocytic skin with respect to pigmentation level is analysed by laser-induced breakdown spectroscopy (LIBS) to investigate the applicability of LIBS as an in situ feedback tool for selective and complete laser removal of melanocytic skin tissue like nevus. The skin of black silkie chicken which had a characteristic darkly pigmented perifollicular skin surrounded by lightly pigmented extrafollicular skin was used as the sample. The results showed higher LIBS signal intensities of Ca 2+ and Mg 2+ but lower intensities of Na + , Cl - and K + in the perifollicular skin than in the extrafollicular skin, which demonstrated the feasibility to use LIBS as a reliable method to distinguish skin tissues with difference in pigmentation level. Plasma emission of biochemical elements generated with a laser irradiation on melanocytic skin lesion. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. 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. Copyright © 2013 Wiley Periodicals, Inc.

  6. 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.

  7. Automated Dermoscopy Image Analysis of Pigmented Skin Lesions

    PubMed Central

    Baldi, Alfonso; Quartulli, Marco; Murace, Raffaele; Dragonetti, Emanuele; Manganaro, Mario; Guerra, Oscar; Bizzi, Stefano

    2010-01-01

    Dermoscopy (dermatoscopy, epiluminescence microscopy) is a non-invasive diagnostic technique for the in vivo observation of pigmented skin lesions (PSLs), allowing a better visualization of surface and subsurface structures (from the epidermis to the papillary dermis). This diagnostic tool permits the recognition of morphologic structures not visible by the naked eye, thus opening a new dimension in the analysis of the clinical morphologic features of PSLs. In order to reduce the learning-curve of non-expert clinicians and to mitigate problems inherent in the reliability and reproducibility of the diagnostic criteria used in pattern analysis, several indicative methods based on diagnostic algorithms have been introduced in the last few years. Recently, numerous systems designed to provide computer-aided analysis of digital images obtained by dermoscopy have been reported in the literature. The goal of this article is to review these systems, focusing on the most recent approaches based on content-based image retrieval systems (CBIR). PMID:24281070

  8. Shining Light on Skin Pigmentation: The Darker and the Brighter Side of Effects of UV Radiation†

    PubMed Central

    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 provide 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 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 a) the mechanisms of involved in selective effects of subcomponents of UV radiation on human skin pigmentation and b) 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 non-ionizing solar radiation, at cellular and molecular levels, on human skin pigmentation. PMID:22404235

  9. 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. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.

  10. [Two cases of skin pigmentation in association with minocycline therapy (author's transl)].

    PubMed

    Leroy, J P; Dorval, J C; Dewitte, J D; Guillerm, D; Volant, A; Masse, R

    1981-01-01

    Report of two cases of skin pigmentation during minocycline therapy. Examination showed confluent blue-gray oval patches on the anterior part of the legs, occurring after ingestion of respectively 12 g and 100 g of minocycline. Microscopic examination of each case was identical and showed two lesions: increase in the amount of melanine deposition in the basal layer of the epidermis; presence of brown-black pigment at all the level of the dermis but specially near the sweet glands. This pigment was strongly positive with Perls' stain. Electron microscopic examination showed a finely granular pigment exclusively intracellular in dermis fibroblast and macrophage. This pigment seemed to contain mainly hemodiderine.

  11. 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. Copyright © 2016 Elsevier Inc. All rights reserved.

  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

    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.

  13. Are there mechanistic differences between ultraviolet and visible radiation induced skin pigmentation?

    PubMed

    Ramasubramaniam, Rajagopal; Roy, Arindam; Sharma, Bharati; Nagalakshmi, Surendra

    2011-12-01

    Most of the studies on sunlight-induced pigmentation of skin are mainly focused on ultraviolet (UV) radiation-induced pigmentation and ways to prevent it. Recent studies have shown that the visible component of sunlight can also cause significant skin pigmentation. In the current study, the extent of pigmentation induced by UV and visible regions of sunlight in subjects with Fitzpatrick skin type IV-V was measured and compared with pigmentation induced by total sunlight. The immediate pigment darkening (IPD) induced by the visible fraction of sunlight is not significantly different from that induced by the UV fraction. However, the persistent pigment darkening (PPD) induced by visible fraction of sunlight in significantly lower than that induced by the UV fraction. The dose responses of IPD induced by UV, visible light and total sunlight suggest that both UV and visible light interact with the same precursor although UV is 25 times more efficient in inducing pigmentation per J cm(-2) of irradiation compared to visible radiation. The measured diffused reflection spectra and decay kinetics of UV and visible radiation-induced pigmentation are very similar, indicating that the nature of the transient and persistent species involved in both the processes are also likely to be same.

  14. A molecular systems approach to modelling human skin pigmentation: identifying underlying pathways and critical components.

    PubMed

    Raghunath, Arathi; Sambarey, Awanti; Sharma, Neha; Mahadevan, Usha; Chandra, Nagasuma

    2015-04-29

    Ultraviolet radiations (UV) serve as an environmental stress for human skin, and result in melanogenesis, with the pigment melanin having protective effects against UV induced damage. This involves a dynamic and complex regulation of various biological processes that results in the expression of melanin in the outer most layers of the epidermis, where it can exert its protective effect. A comprehensive understanding of the underlying cross talk among different signalling molecules and cell types is only possible through a systems perspective. Increasing incidences of both melanoma and non-melanoma skin cancers necessitate the need to better comprehend UV mediated effects on skin pigmentation at a systems level, so as to ultimately evolve knowledge-based strategies for efficient protection and prevention of skin diseases. A network model for UV-mediated skin pigmentation in the epidermis was constructed and subjected to shortest path analysis. Virtual knock-outs were carried out to identify essential signalling components. We describe a network model for UV-mediated skin pigmentation in the epidermis. The model consists of 265 components (nodes) and 429 directed interactions among them, capturing the manner in which one component influences the other and channels information. Through shortest path analysis, we identify novel signalling pathways relevant to pigmentation. Virtual knock-outs or perturbations of specific nodes in the network have led to the identification of alternate modes of signalling as well as enabled determining essential nodes in the process. The model presented provides a comprehensive picture of UV mediated signalling manifesting in human skin pigmentation. A systems perspective helps provide a holistic purview of interconnections and complexity in the processes leading to pigmentation. The model described here is extensive yet amenable to expansion as new data is gathered. Through this study, we provide a list of important proteins essential

  15. Transcriptomic analysis of skin pigmentation variation in the Virginia opossum (Didelphis virginiana).

    PubMed

    Nigenda-Morales, Sergio F; Hu, Yibo; Beasley, James C; Ruiz-Piña, Hugo A; Valenzuela-Galván, David; Wayne, Robert K

    2018-06-01

    Skin pigmentation and coat pigmentation are two of the best-studied examples of traits under natural selection given their quantifiable fitness interactions with the environment (e.g., camouflage) and signalling with other organisms (e.g., warning coloration). Previous morphological studies have found that skin pigmentation variation in the Virginia opossum (Didelphis virginiana) is associated with variation in precipitation and temperatures across its distribution range following Gloger's rule (lighter pigmentation in temperate environments). To investigate the molecular mechanism associated with skin pigmentation variation, we used RNA-Seq and quantified gene expression of wild opossums from tropical and temperate populations. Using differential expression analysis and a co-expression network approach, we found that expression variation in genes with melanocytic and immune functions is significantly associated with the degree of skin pigmentation variation and may be underlying this phenotypic difference. We also found evidence suggesting that the Wnt/β-catenin signalling pathway might be regulating the depigmentation observed in temperate populations. Based on our study results, we present several alternative hypotheses that may explain Gloger's rule pattern of skin pigmentation variation in opossum, including changes in pathogen diversity supporting a pathogen-resistant hypothesis, thermal stress associated with temperate environments, and pleiotropic and epistatic interactions between melanocytic and immune genes. © 2018 John Wiley & Sons Ltd.

  16. Effects of skin pigmentation on pulse oximeter accuracy at low saturation.

    PubMed

    Bickler, Philip E; Feiner, John R; Severinghaus, John W

    2005-04-01

    It is uncertain whether skin pigmentation affects pulse oximeter accuracy at low HbO2 saturation. The accuracy of finger pulse oximeters during stable, plateau levels of arterial oxygen saturation (Sao2) between 60 and 100% were evaluated in 11 subjects with darkly pigmented skin and in 10 with light skin pigmentation. Oximeters tested were the Nellcor N-595 with the OxiMax-A probe (Nellcor Inc., Pleasanton, CA), the Novametrix 513 (Novametrix Inc., Wallingford, CT), and the Nonin Onyx (Nonin Inc., Plymouth, MN). Semisupine subjects breathed air-nitrogen-carbon dioxide mixtures through a mouthpiece. A computer used end-tidal oxygen and carbon dioxide concentrations determined by mass spectrometry to estimate breath-by-breath Sao2, from which an operator adjusted inspired gas to rapidly achieve 2- to 3-min stable plateaus of desaturation. Comparisons of oxygen saturation measured by pulse oximetry (Spo2) with Sao2 (by Radiometer OSM3) were used in a multivariate model to determine the interrelation between saturation, skin pigmentation, and oximeter bias (Spo2 - Sao2). At 60-70% Sao2, Spo2 (mean of three oximeters) overestimated Sao2 (bias +/- SD) by 3.56 +/- 2.45% (n = 29) in darkly pigmented subjects, compared with 0.37 +/- 3.20% (n = 58) in lightly pigmented subjects (P < 0.0001). The SD of bias was not greater with dark than light skin. The dark-light skin differences at 60-70% Sao2 were 2.35% (Nonin), 3.38% (Novametrix), and 4.30% (Nellcor). Skin pigment-related differences were significant with Nonin below 70% Sao2, with Novametrix below 90%, and with Nellcor at all ranges. Pigment-related bias increased approximately in proportion to desaturation. The three tested pulse oximeters overestimated arterial oxygen saturation during hypoxia in dark-skinned individuals.

  17. 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

  18. Genomic ancestry, self-reported "color" and quantitative measures of skin pigmentation in Brazilian admixed siblings.

    PubMed

    Leite, Tailce K M; Fonseca, Rômulo M C; de França, Nanci M; Parra, Esteban J; Pereira, Rinaldo W

    2011-01-01

    A current concern in genetic epidemiology studies in admixed populations is that population stratification can lead to spurious results. The Brazilian census classifies individuals according to self-reported "color", but several studies have demonstrated that stratifying according to "color" is not a useful strategy to control for population structure, due to the dissociation between self-reported "color" and genomic ancestry. We report the results of a study in a group of Brazilian siblings in which we measured skin pigmentation using a reflectometer, and estimated genomic ancestry using 21 Ancestry Informative Markers (AIMs). Self-reported "color", according to the Brazilian census, was also available for each participant. This made it possible to evaluate the relationship between self-reported "color" and skin pigmentation, self-reported "color" and genomic ancestry, and skin pigmentation and genomic ancestry. We observed that, although there were significant differences between the three "color" groups in genomic ancestry and skin pigmentation, there was considerable dispersion within each group and substantial overlap between groups. We also saw that there was no good agreement between the "color" categories reported by each member of the sibling pair: 30 out of 86 sibling pairs reported different "color", and in some cases, the sibling reporting the darker "color" category had lighter skin pigmentation. Socioeconomic status was significantly associated with self-reported "color" and genomic ancestry in this sample. This and other studies show that subjective classifications based on self-reported "color", such as the one that is used in the Brazilian census, are inadequate to describe the population structure present in recently admixed populations. Finally, we observed that one of the AIMs included in the panel (rs1426654), which is located in the known pigmentation gene SLC24A5, was strongly associated with skin pigmentation in this sample.

  19. LIGR, a protease-activated receptor-2-derived peptide, enhances skin pigmentation without inducing inflammatory processes.

    PubMed

    Lin, Connie B; Chen, Nannan; Scarpa, Richard; Guan, Fei; Babiarz-Magee, Laura; Liebel, Frank; Li, Wen-Hwa; Kizoulis, Menas; Shapiro, Stanley; Seiberg, Miri

    2008-04-01

    The protease-activated receptor-2 (PAR-2) is a seven transmembrane G-protein-coupled receptor that could be activated by serine protease cleavage or by synthetic peptide agonists. We showed earlier that activation of PAR-2 with Ser-Leu-Ile-Gly-Arg-Leu-NH(2) (SLIGRL), a known PAR-2 activating peptide, induces keratinocyte phagocytosis and increases skin pigmentation, indicating that PAR-2 regulates pigmentation by controlling phagocytosis of melanosomes. Here, we show that Leu-Ile-Gly-Arg-NH(2) (LIGR) can also induce skin pigmentation. Both SLIGRL and LIGR increased melanin deposition in vitro and in vivo, and visibly darkened human skins grafted onto severe combined immuno-deficient (SCID) mice. Both SLIGRL and LIGR stimulated Rho-GTP activation resulting in keratinocyte phagocytosis. Interestingly, LIGR activates only a subset of the PAR-2 signaling pathways, and unlike SLIGRL, it does not induce inflammatory processes. LIGR did not affect many PAR-2 signaling pathways, including [Ca(2+)] mobilization, cAMP induction, the induction of cyclooxgenase-2 (COX-2) expression and the secretion of prostaglandin E2, interleukin-6 and -8. PAR-2 siRNA inhibited LIGR-induced phagocytosis, indicating that LIGR signals via PAR-2. Our data suggest that LIGR is a more specific regulator of PAR-2-induced pigmentation relative to SLIGRL. Therefore, enhancing skin pigmentation by topical applications of LIGR may result in a desired tanned-like skin color, without enhancing inflammatory processes, and without the need of UV exposure.

  20. Use of human skin reconstructs in the study of pigment modifiers.

    PubMed

    Bessou, S; Pain, C; Taïeb, A

    1997-03-01

    To assay drugs that modify pigmentation (ie, agents that either enhance or decrease pigmentation) in a predictive in vitro model, as such drugs have been previously studied in vivo on human and animal skin. An epidermis was reconstructed with human keratinocytes and melanocytes. Epidermal reconstructs with melanocytes were made according to a variant of the model of Pruniéras and colleagues. Reagents that alter melanogenesis such as isobutyl methylxanthine, 1-oleoyl-2-acetyl-sn-glycerol, kojic acid, and mequinol were introduced in the culture medium or used topically after 8 days of culture at the air-liquid interface. Macroscopic, colorimetric, histological (Fontana-Masson stain and dopa reaction), and biochemical studies were performed. The effect of pigment modifiers was demonstrated ex vivo as expected from in vivo data on skin color, numbers of melanocytes, melanosome transfer, and melanin content. These results will permit other investigators to use this model to assess the efficacy of novel molecules that alter pigmentation.

  1. 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.

  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. The impact of human immunodeficiency virus-related diseases on pigmented skin types.

    PubMed

    Ameen, M

    2013-10-01

    Infection with human immunodeficiency virus (HIV) remains a significant problem globally. Early diagnosis and treatment with antiretroviral drugs has considerably improved health outcomes and decreased disease-related morbidity. HIV infection is associated with a wide range of skin disorders enabling dermatologists to diagnose HIV as well as associated opportunistic infections early in the course of disease. Despite concerted efforts by international health organizations to limit disease incidence, the prevalence of HIV infection remains high and is highest in sub-Saharan Africa. The diagnosis of HIV-related skin diseases is challenging as immunosuppression often results in atypical disease presentation. In addition, the clinical presentation will vary in pigmented skin types. The aim of this article is to describe disease variation in pigmented skin types. © 2013 The Author BJD © 2013 British Association of Dermatologists.

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

    PubMed

    Choi, Hyunjung; Shin, Ji Hyun; 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.

  5. IFN-γ signaling maintains skin pigmentation homeostasis through regulation of melanosome maturation

    PubMed Central

    Natarajan, Vivek T.; Ganju, Parul; Singh, Archana; Vijayan, Vinaya; Kirty, Kritika; Yadav, Shalini; Puntambekar, Shraddha; Bajaj, Sonali; Dani, Prachi P.; Kar, Hemanta K.; Gadgil, Chetan J.; Natarajan, Krishnamurthy; Rani, Rajni; Gokhale, Rajesh S.

    2014-01-01

    Cellular homeostasis is an outcome of complex interacting processes with nonlinear feedbacks that can span distinct spatial and temporal dimensions. Skin tanning is one such dynamic response that maintains genome integrity of epidermal cells. Although pathways underlying hyperpigmentation cascade are recognized, negative feedback regulatory loops that can dampen the activated melanogenesis process are not completely understood. In this study, we delineate a regulatory role of IFN-γ in skin pigmentation biology. We show that IFN-γ signaling impedes maturation of the key organelle melanosome by concerted regulation of several pigmentation genes. Withdrawal of IFN-γ signal spontaneously restores normal cellular programming. This effect in melanocytes is mediated by IFN regulatory factor-1 and is not dependent on the central regulator microphthalmia-associated transcription factor. Chronic IFN-γ signaling shows a clear hypopigmentation phenotype in both mouse and human skin. Interestingly, IFN-γ KO mice display a delayed recovery response to restore basal state of epidermal pigmentation after UV-induced tanning. Together, our studies delineate a new spatiotemporal role of the IFN-γ signaling network in skin pigmentation homeostasis, which could have implications in various cutaneous depigmentary and malignant disorders. PMID:24474804

  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. Inhibiting roles of melanin-concentrating hormone for skin pigment dispersion in barfin flounder, Verasper moseri.

    PubMed

    Mizusawa, Kanta; Kobayashi, Yuki; Sunuma, Toshikazu; Asahida, Takashi; Saito, Yumiko; Takahashi, Akiyoshi

    2011-03-01

    Barfin flounders change their surface color pattern to match their background. We have reported evidence of the association between hormones and body color changes in this fish. First, bolus intraperitoneal injection with melanin-concentrating hormone (MCH) immediately turned the skin color pale, while injection with melanocyte-stimulating hormone (MSH) did not change the skin color. Second, gene expression levels of MCH change in response to background color, while those of MSH do not. We also reported the expression of an MCH receptor gene (Mch-r2) in the skin of this fish. In this study, we aimed to further evaluate the roles of MCH in skin color change. First, long-term adaptation of adult barfin flounder to black or white background colors induced significantly different pigment migration patterns in both melanophores and xanthophores (P<0.05). However, continuous intraperitoneal injection with MCH did not influence chromatophore proliferation. Then, using in vitro experiments, we found that MCH aggregates both melanophores and xanthophores, and inhibits the pigment-dispersing activity of MSH in a similar manner. Finally, we identified transcripts of Mch-r2 in cells isolated from both melanophores and xanthophores. Taken together, the evidence suggests that MCH aggregates pigments via MCH-R2 in concert with the nervous system by overcoming the melanin-dispersing activities of MSH in barfin flounder. Copyright © 2010 Elsevier Inc. All rights reserved.

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

    PubMed

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

    2016-04-26

    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.

  10. 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.

  11. Use of multiphoton tomography and fluorescence lifetime imaging to investigate skin pigmentation in vivo.

    PubMed

    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.

  12. 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

  13. 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

  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

    2018-01-01

    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 with baseline high-resolution three-dimensional total-body photography, we observed fading or disappearance of solar lentigines, seborrhoeic 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 seborrhoeic keratosis with melanophages. Further studies are required to elucidate the effects of PD-1 inhibition on benign skin lesions. © 2017 British Association of Dermatologists.

  15. Skin Erythema, Pigmentation and Hydration Kinetics after Ultraviolet Radiation-induced Photodamage in Southern Chinese Women.

    PubMed

    Wan, Miaojian; Hu, Rong; Xie, Xiaoyuan; Gong, Zijian; Yi, Jinling; Chen, Haiyan; Xie, Lin; Guan, Xiaomin; Guan, Lei; Lai, Wei

    2017-10-01

    Although there have been some studies about changes of skin erythema and pigmentation following ultraviolet radiation in other races, the relevant data in Chinese have never been achieved. Thus, we evaluated the long-time course of skin erythema, pigmentation and hydration changes after different doses of solar-simulated ultraviolet (SSUV) irradiation in 26 Chinese women for 168 days. The erythema index increased abruptly and peaked during 3 days of SSUV exposure, then slowly returned to the baseline level starting at day 7 and completely recovered during 168-day course of this study only in one minimal erythema doses (MED) SSUV irradiation. The melanin index started to slowly increase at day 3 of SSUV exposure, peaking at day 14 and gradually returned to the baseline level thereafter, but did not return to the baseline level during 168-day course in all doses. Skin hydration slowly declined at day 3 of exposure, hitting the lowest point at day 7, then slowly recovered starting at day 14 and completely returned to the baseline level at day 28 only in 1.5MED. These results will serve as baseline data on Chinese skin and provide useful references for the treatment of serious skin photodamage in Chinese. © 2017 The American Society of Photobiology.

  16. Anaemia and skin pigmentation after excessive cupping therapy by an unqualified therapist in Korea: a case report.

    PubMed

    Kim, Kun Hyung; Kim, Tae-Hun; Hwangbo, Min; Yang, Gi Young

    2012-09-01

    A case is reported of skin pigmentation and associated anemia resulting from persistently repeated cupping therapies performed by an unqualified practitioner in South Korea. Almost 30 sessions of excessive cupping therapies with blood loss over two months yielded little benefit but led the patient to admit a hospital and receive blood transfusion for acquired iron deficiency anemia. Skin pigmentation on the cupping-attached region remained without any subjective discomfort. We suggest the importance of qualified health professionals when receiving cupping treatments.

  17. 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. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  18. Regulation of skin pigmentation and thickness by dickkopf 1 (DKK1)

    PubMed Central

    Yamaguchi, Yuji; Morita, Akimichi; Maeda, Akira; Hearing, Vincent J.

    2009-01-01

    Dickkopf 1 (DKK1), an inhibitor of Wnt signaling, not only functions as a head inducer during development, but also regulates joint remodeling and bone formation, which suggests roles for DKK1 in the pathogenesis of rheumatoid arthritis and multiple myeloma. We recently demonstrated that levels of DKK1 in palmoplantar dermal fibroblasts are physiologically higher than those observed in non-palmoplantar dermal fibroblasts. Thus, the DKK1-rich mesenchyme in palmoplantar dermis affects the overlying epithelium and induces a palmoplantar phenotype in the epidermis. More specifically, DKK1 suppresses melanocyte function and growth via the regulation of microphthalmia-associated transcription factor (MITF) and β-catenin. Furthermore, DKK1 induces the expression of keratin 9 and α-Kelch-like ECT2 interacting protein (αKLEIP) but down-regulates the expression of β-catenin, glycogen synthase kinase 3β, protein kinase C and proteinase-activated receptor-2 (PAR-2) in keratinocytes. Treatment of reconstructed skin with DKK1 reproduces the hypopigmentation and thickening of skin via Wnt/β-catenin signaling. These studies elucidate why human palmoplantar skin is thicker and paler than non-palmoplantar skin via the secretion of DKK1 by fibroblasts that affect the overlying epidermis. Thus, DKK1 may be useful for reducing skin pigmentation and for thickening photo-aged skin and palmoplantar wounds caused by diabetes mellitus and rheumatic skin diseases. PMID:19675559

  19. Assessment of skin pigmentation by confocal microscopy: Influence of solar exposure and protection habits on cutaneous hyperchromias.

    PubMed

    Martini, Ana Paula M; Mercurio, Daiane G; Maia Campos, Patrícia M B G

    2017-09-01

    Cutaneous hyperchromias are disorders of skin pigmentation involving an increase of melanin production and its irregular accumulation in skin cells. It is known that the use of sunscreens helps to prevent changes in the skin pigmentation pattern, but the structural and morphological alterations that occur in the different types of hyperpigmentations need better elucidation. To assess the influence of solar exposure and protection habits on the pattern of skin pigmentation using reflectance confocal microscopy (RCM). Forty volunteers aged 18-39 years with skin hyperpigmentation participated in the study. Skin characterization was performed by imaging techniques and by assessing the habits of solar exposure and protection by applying questionnaires to the volunteers. RCM was used to record sequences of confocal sections at areas of interest and to examine cell shape and brightness in the basal cell layer of the lesion and in normal perilesional skin. Furthermore, high-resolution images were obtained for analysis of the spots. Sunlight influences the number and location of spots as the face of volunteers with higher solar exposure was covered with spots, whereas volunteers with less exposure had fewer spots located in the nose and cheeks region due to greater exposure of these areas to the sun. The data showed the importance of sun protection for preventing changes in the pattern of skin pigmentation, and RCM proved to be an important tool for skin characterization. © 2017 Wiley Periodicals, Inc.

  20. 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.

  1. Autosomal-recessive SASH1 variants associated with a new genodermatosis with pigmentation defects, palmoplantar keratoderma and skin carcinoma

    PubMed Central

    Courcet, Jean- Benoît; Elalaoui, Siham Chafai; Duplomb, Laurence; Tajir, Mariam; Rivière, Jean-Baptiste; Thevenon, Julien; Gigot, Nadège; Marle, Nathalie; Aral, Bernard; Duffourd, Yannis; Sarasin, Alain; Naim, Valeria; Courcet-Degrolard, Emilie; Aubriot-Lorton, Marie- Hélène; Martin, Laurent; Abrid, Jamal Eddin; Thauvin, Christel; Sefiani, Abdelaziz; Vabres, Pierre; Faivre, Laurence

    2015-01-01

    SASH1 (SAM and SH3 domain-containing protein 1) is a tumor suppressor gene involved in the tumorigenesis of a spectrum of solid cancers. Heterozygous SASH1 variants are known to cause autosomal-dominant dyschromatosis. Homozygosity mapping and whole-exome sequencing were performed in a consanguineous Moroccan family with two affected siblings presenting an unclassified phenotype associating an abnormal pigmentation pattern (hypo- and hyperpigmented macules of the trunk and face and areas of reticular hypo- and hyperpigmentation of the extremities), alopecia, palmoplantar keratoderma, ungueal dystrophy and recurrent spinocellular carcinoma. We identified a homozygous variant in SASH1 (c.1849G>A; p.Glu617Lys) in both affected individuals. Wound-healing assay showed that the patient's fibroblasts were better able than control fibroblasts to migrate. Following the identification of SASH1 heterozygous variants in dyschromatosis, we used reverse phenotyping to show that autosomal-recessive variants of this gene could be responsible for an overlapping but more complex phenotype that affected skin appendages. SASH1 should be added to the list of genes responsible for autosomal-dominant and -recessive genodermatosis, with no phenotype in heterozygous patients in the recessive form, and to the list of genes responsible for a predisposition to skin cancer. PMID:25315659

  2. Autosomal-recessive SASH1 variants associated with a new genodermatosis with pigmentation defects, palmoplantar keratoderma and skin carcinoma.

    PubMed

    Courcet, Jean-Benoît; Elalaoui, Siham Chafai; Duplomb, Laurence; Tajir, Mariam; Rivière, Jean-Baptiste; Thevenon, Julien; Gigot, Nadège; Marle, Nathalie; Aral, Bernard; Duffourd, Yannis; Sarasin, Alain; Naim, Valeria; Courcet-Degrolard, Emilie; Aubriot-Lorton, Marie-Hélène; Martin, Laurent; Abrid, Jamal Eddin; Thauvin, Christel; Sefiani, Abdelaziz; Vabres, Pierre; Faivre, Laurence

    2015-07-01

    SASH1 (SAM and SH3 domain-containing protein 1) is a tumor suppressor gene involved in the tumorigenesis of a spectrum of solid cancers. Heterozygous SASH1 variants are known to cause autosomal-dominant dyschromatosis. Homozygosity mapping and whole-exome sequencing were performed in a consanguineous Moroccan family with two affected siblings presenting an unclassified phenotype associating an abnormal pigmentation pattern (hypo- and hyperpigmented macules of the trunk and face and areas of reticular hypo- and hyperpigmentation of the extremities), alopecia, palmoplantar keratoderma, ungueal dystrophy and recurrent spinocellular carcinoma. We identified a homozygous variant in SASH1 (c.1849G>A; p.Glu617Lys) in both affected individuals. Wound-healing assay showed that the patient's fibroblasts were better able than control fibroblasts to migrate. Following the identification of SASH1 heterozygous variants in dyschromatosis, we used reverse phenotyping to show that autosomal-recessive variants of this gene could be responsible for an overlapping but more complex phenotype that affected skin appendages. SASH1 should be added to the list of genes responsible for autosomal-dominant and -recessive genodermatosis, with no phenotype in heterozygous patients in the recessive form, and to the list of genes responsible for a predisposition to skin cancer.

  3. 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

  4. Discrimination between cutaneous pigmentation and erythema: comparison of the skin colorimeters Dermacatch and Mexameter.

    PubMed

    Baquié, M; Kasraee, B

    2014-05-01

    Reproducibility and specificity of the present skin colorimeters is still limited as alterations in erythema can bias the measurement of melanin and vice versa. Here, Dermacatch(®) , a new colorimeter covering the visible light spectrum, has been compared with Mexameter(®) , an established narrow-band reflectance spectrophotometer. Repeated measurements with both devices were initially collected on colour charts. Then, measures were compared on 12 human volunteers before and after exposure to UVB, and/or modulation of skin erythema. In vitro sensitivity of Dermacatch to erythema/melanin covered a broader wavelength spectrum than Mexameter while in vivo sensitivity of both devices was similar. Interestingly, Mexameter's melanin and erythema values were falsely affected by an increase in erythema or variation in pigmentation respectively. On the contrary, Dermacatch's melanin and erythema values remained constant in the same circumstances. Furthermore, as Mexameter was at least twice less reproducible than Dermacatch, Mexameter showed an increased risk of a confusion over the detection of erythema or melanin fluctuations. The analysis of more than 18,000 measures indicated that, Dermacatch has a significantly higher specificity and reproducibility than Mexameter in the measurement of skin pigmentation and erythema. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Pigmentation abnormalities in systemic scleroderma examined by using a colorimeter (Choromo Meter CR-200).

    PubMed

    Maeda, M; Kachi, H; Matubara, K; Mori, S; Kitajima, Y

    1996-03-01

    Cutaneous colors of the dorsum of the hands (A), the distal forearms (B; 5 cm from the wrists), the proximal forearm (C; proximal 1/3 from the elbow) and sternal skin region (D) in patients with systemic scleroderma (73 cases; M:F = 16:57) systemic lupus erythematosus (SLE) or dermatomyositis (27 cases; M:F = 7:20) and healthy controls (HC) (36 cases; M:F = 8:28) was characterized by a XYZ colorimetric system (CIE, 1931) using a colorimeter (Choromo Meter CR-200, Minolta Camera Co. Ltd., Osaka). The index Y, which means color value shows a lower value in male HC and in patients with systemic scleroderma, especially in the more severe type with hyperpigmentation (score 5-6; the system proposed by Ishikawa) than that of female HC. The values of indices x and y, which relate to reddish (erythema with hyperpigmentation) and greenish color (pale), respectively, were higher in the exposed portion of the severe type of systemic scleroderma with hyperpigmentation, especially male and older patients, and in unexposed portions of the female group without hyperpigmentation. Histopathologically, there was prominent pigmentation in the upper dermis of the forearm in the severe type of systemic scleroderma, so that melanin quantity may be closely related to the decrease in index Y. There was no statistical significance in the value of indices Y, x and y between HC, SLE and dermatomyositis. This method may contribute not only to diagnosis of systemic scleroderma and differentiation from other collagen diseases, but also studies of clinical follow-up and effects of medication.

  6. Effects of glycolic acid on light-induced skin pigmentation in Asian and caucasian subjects.

    PubMed

    Tsai, T F; Bowman, P H; Jee, S H; Maibach, H I; Paul, B H

    2000-08-01

    Topical use of alpha-hydroxy acid (AHA) may increase skin photosensitivity, as demonstrated by increased numbers of sunburst cells. However, effects of AHA on tanning have not been studied. Our purpose was to study whether short-term use of glycolic acid hastens resolution of pre-existing light-induced pigmentation and whether the skin becomes tan more easily in Asian and Caucasian subjects after such treatment. Six Asian and six Caucasian volunteers received separate irradiations of UVB and UVA to both sides of the lower back. In a double-blind fashion, patients then applied a 10% glycolic acid gel, pH 3.52, to one side of the back, including the irradiated area, and the contralateral extensor forearms once daily for 7 days and then twice daily for 2 weeks. A placebo gel, pH 5.75, was applied to the opposite sides. The subjects returned for measurement of residual tanning with a colorimeter and received additional irradiation to forearms and a second site on the back. Resulting pigmentation was measured immediately after irradiation, at 2 hours, and at 1 week. Increased UVB-induced skin tanning occurred on the forearm and the lower back in both races in areas pretreated with glycolic acid. UVA also caused increased tanning, but only on the extensor forearms in Asian subjects. Treatment with glycolic acid for 3 weeks had no effect on pre-existing light-induced pigmentation. Short-term topical treatment of glycolic acid caused an increase in UVB tanning as well as in UVA tanning in some subjects, even in the absence of overt irritation. The inclusion of UVB, and even UVA, sunscreen in AHA products may be warranted.

  7. A new quantitative evaluation method for age-related changes of individual pigmented spots in facial skin.

    PubMed

    Kikuchi, K; Masuda, Y; Yamashita, T; Sato, K; Katagiri, C; Hirao, T; Mizokami, Y; Yaguchi, H

    2016-08-01

    Facial skin pigmentation is one of the most prominent visible features of skin aging and often affects perception of health and beauty. To date, facial pigmentation has been evaluated using various image analysis methods developed for the cosmetic and esthetic fields. However, existing methods cannot provide precise information on pigmented spots, such as variations in size, color shade, and distribution pattern. The purpose of this study is the development of image evaluation methods to analyze individual pigmented spots and acquire detailed information on their age-related changes. To characterize the individual pigmented spots within a cheek image, we established a simple object-counting algorithm. First, we captured cheek images using an original imaging system equipped with an illumination unit and a high-resolution digital camera. The acquired images were converted into melanin concentration images using compensation formulae. Next, the melanin images were converted into binary images. The binary images were then subjected to noise reduction. Finally, we calculated parameters such as the melanin concentration, quantity, and size of individual pigmented spots using a connected-components labeling algorithm, which assigns a unique label to each separate group of connected pixels. The cheek image analysis was evaluated on 643 female Japanese subjects. We confirmed that the proposed method was sufficiently sensitive to measure the melanin concentration, and the numbers and sizes of individual pigmented spots through manual evaluation of the cheek images. The image analysis results for the 643 Japanese women indicated clear relationships between age and the changes in the pigmented spots. We developed a new quantitative evaluation method for individual pigmented spots in facial skin. This method facilitates the analysis of the characteristics of various pigmented facial spots and is directly applicable to the fields of dermatology, pharmacology, and esthetic

  8. 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

  9. Pigmentation Phenotype, Photosensitivity, and Skin Neoplasms in Patients with Myotonic Dystrophy

    PubMed Central

    Gadalla, Shahinaz M.; Hilbert, James E.; Martens, William B.; Givens, Shannon; Moxley, Richard T.; Greene, Mark H.

    2017-01-01

    Background Recent studies have suggested a possible excess risk of skin neoplasms in patients with myotonic dystrophy (DM). Risk factors related to this observation have not been defined. Method We collected information regarding personal history of skin tumors, pigmentation phenotype, and skin reaction to sun exposure from 266 DM patients who were enrolled in the US NIH National Registry of Myotonic Dystrophy and Facioscapulohumeral Muscular Dystrophy Patients and Family Members. Results Seventy-seven subjects reported having skin tumors that were either benign (n=31), malignant (n=32), or both (n=14). Female gender (OR=2.27, 95%CI=1.02–5.05, p=0.04), older age (OR=1.10, 95%CI=1.05–1.16, p<0.001), and DM1 subtype (OR=3.42, 95%CI=1.27–9.26, p=0.02) were associated with a malignant skin tumor. The association between malignant skin tumors and known risk factors [light eye color (OR=1.62, 95%CI=0.78–3.39, p=0.20); light skin complexion (OR=1.31, 95% CI=0.63–2.73, p=0.48), moderate/extensive face freckles (OR=1.47, 95% CI=0.50–4.34, p=0.49)] were modest. Strong, but not statistically significant, associations were noted with sunburn reactions when exposed to sunlight (OR=4.28, 95%CI=0.91–19.95, p=0.06, and 2.19, 95%CI=0.67–7.09, p=0.19 for sunburns with and without blistering, respectively). Conclusions Although our study was limited by small sample size, the risk factors for malignant skin tumors in DM strongly resemble the general population. We recommend that DM patients adhere to sun exposure protective behavior. PMID:28317292

  10. Bull's eye and pigment maculopathy are further retinal manifestations of an abnormal Bruch's membrane in Alport syndrome.

    PubMed

    Savige, Judy; Wang, Yanyan; Crawford, Andrew; Smith, James; Symons, Andrew; Mack, Heather; Nicholls, Kathy; Wilson, Diane; Colville, Deb

    2017-01-01

    The retinal features of Alport syndrome include a central and peripheral fleck retinopathy, temporal retinal thinning, and a macular hole. Here we describe further retinal abnormalities. We identified a case of bull's eye maculopathy 20 years previously in a 68-year-old female, and reviewed archived retinal images from our cohort of X-linked (28 males, 28 females) or autosomal recessive (n = 13) Alport syndrome. All individuals had Alport syndrome confirmed on genetic testing or renal biopsy, were examined by an ophthalmologist, and underwent retinal imaging (KOWA non-mydriatic camera, Japan). The index case had the p.Q379X variant in COL4A5 and currently had renal impairment, (eGFR = 45 ml/min/1.73 m 2 ), bilateral hearing loss, and central and peripheral retinopathies. Her maculopathy had deteriorated, and she had a bilateral central visual field loss. Optical coherence tomography (Heidelberg Spectralis) demonstrated a disrupted retinal pigment epithelium and retinal atrophy. We identified a further early bull's eye maculopathy (1/69, 1.4%) from a female with autosomal recessive disease and normal renal function. We also noted a subtle pigment maculopathy associated with an abnormal retinal pigment epithelium in 27 (27/69, 39%) subjects with Alport syndrome, in both males (8/28, 29%) and females (13/28, 46%) with X-linked disease, and in autosomal recessive disease (6/13, 38%). The bull's eye and pigment maculopathies in Alport syndrome result mainly from the damaged Bruch's membrane and overlying retinal pigment epithelium. Bull's eye maculopathy affects vision and patients should undergo regular monitoring for retinal complications.

  11. Genomic Ancestry, Self-Reported “Color” and Quantitative Measures of Skin Pigmentation in Brazilian Admixed Siblings

    PubMed Central

    Leite, Tailce K. M.; Fonseca, Rômulo M. C.; de França, Nanci M.; Parra, Esteban J.; Pereira, Rinaldo W.

    2011-01-01

    A current concern in genetic epidemiology studies in admixed populations is that population stratification can lead to spurious results. The Brazilian census classifies individuals according to self-reported “color”, but several studies have demonstrated that stratifying according to “color” is not a useful strategy to control for population structure, due to the dissociation between self-reported “color” and genomic ancestry. We report the results of a study in a group of Brazilian siblings in which we measured skin pigmentation using a reflectometer, and estimated genomic ancestry using 21 Ancestry Informative Markers (AIMs). Self-reported “color”, according to the Brazilian census, was also available for each participant. This made it possible to evaluate the relationship between self-reported “color” and skin pigmentation, self-reported “color” and genomic ancestry, and skin pigmentation and genomic ancestry. We observed that, although there were significant differences between the three “color” groups in genomic ancestry and skin pigmentation, there was considerable dispersion within each group and substantial overlap between groups. We also saw that there was no good agreement between the “color” categories reported by each member of the sibling pair: 30 out of 86 sibling pairs reported different “color”, and in some cases, the sibling reporting the darker “color” category had lighter skin pigmentation. Socioeconomic status was significantly associated with self-reported “color” and genomic ancestry in this sample. This and other studies show that subjective classifications based on self-reported “color”, such as the one that is used in the Brazilian census, are inadequate to describe the population structure present in recently admixed populations. Finally, we observed that one of the AIMs included in the panel (rs1426654), which is located in the known pigmentation gene SLC24A5, was strongly associated with

  12. Genetic variants in pigmentation genes, pigmentary phenotypes, and risk of skin cancer in Caucasians

    PubMed Central

    Nan, Hongmei; Kraft, Peter; Hunter, David J.; Han, Jiali

    2009-01-01

    Human pigmentation is a polygenic quantitative trait with high heritability. Although a large number of single nucleotide polymorphisms (SNPs) have been identified in pigmentation genes, very few SNPs have been examined in relation to human pigmentary phenotypes and skin cancer risk. We evaluated the associations between fifteen SNPs in eight candidate pigmentation genes (TYR, TYRP1, OCA2, SLC24A5, SLC45A2, POMC, ASIP, and ATRN) and both pigmentary phenotypes (hair color, skin color, and tanning ability) and skin cancer risk in a nested case-control study of Caucasians within the Nurses’ Health Study (NHS) among 218 melanoma cases, 285 squamous cell carcinoma (SCC) cases, 300 basal cell carcinoma (BCC) cases, and 870 common controls. We found that the TYR Arg402Gln variant was significantly associated with skin color (p-value =7.7×10−4) and tanning ability (p-value =7.3×10−4); the SLC45A2 Phe374Leu variant was significantly associated with hair color (black to blonde) (p-value =2.4×10−7), skin color (p-value =1.1×10−7), and tanning ability (p-value =2.5×10−4). These associations remained significant after controlling for MC1R variants. No significant associations were found between these polymorphisms and the risk of skin cancer. We observed that the TYRP1 rs1408799 and SLC45A2 -1721 C>G were associated with melanoma risk (OR, 0.77; 95% CI, 0.60–0.98 and OR, 0.75; 95% CI, 0.60–0.95, respectively). The TYR Ser192Tyr was associated with SCC risk (OR, 1.23; 95% CI, 1.00–1.50). The TYR haplotype carrying only the Arg402Gln variant allele was significantly associated with SCC risk (OR, 1.35; 95% CI, 1.04–1.74). The OCA2 Arg419Gln and ASIP g.8818 A>G were associated with BCC risk (OR, 1.50; 95% CI, 1.06–2.13 and OR, 0.73; 95% CI, 0.53–1.00, respectively). The haplotype near ASIP (rs4911414[T] and rs1015362[G]) was significantly associated with fair skin color (OR, 2.28; 95% CI, 1.46–3.57) as well as the risks of melanoma (OR, 1.68; 95% CI

  13. Pulse Width Dependence Of Pigment Cell Damage At 694 nm In Guinea Pig Skin

    NASA Astrophysics Data System (ADS)

    Dover, Jeffrey S.; Polla, Luigi L.; Margolis, Randall J.; Whitaker, Diana; Watanabe, Schinichi; Murphy, George F.; Parrish, John A.; Anderson, R. R.

    1987-03-01

    351 nm, 20-nsec XeF excimer laser irradiation has previously been shown to selectively target and damage melanosomes in human skin. In the following studies selective targeting with melanosomal photodisruption has been demonstrated in pigmented guinea pig skin with a Q-switched 40-nsec ruby laser, and a 750-nsec pulsed dye laser but not with a 400-usec pulsed dye laser. The pulse width dependence of melanosomal disruption, occurring only at pulsewidths shorter than the thermal relaxation time of the melanosome (0.5 - 1.0 usec), is in accordance with the theory of selective photothermolysis. Possible mechanisms of melanosomal photodisruption include development of sudden thermal gradients leading to cavitation or shock wave production.

  14. 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

  15. 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.

  16. 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.

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

    PubMed

    Bonilla, Carolina; Ness, Andrew R; Wills, Andrew K; Lawlor, Debbie A; Lewis, Sarah J; Davey Smith, George

    2014-06-12

    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. 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). 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. 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.

  18. Evidence for antioxidant nutrients-induced pigmentation in skin: results of a clinical trial.

    PubMed

    Postaire, E; Jungmann, H; Bejot, M; Heinrich, U; Tronnier, H

    1997-08-01

    The aim of this study was to demonstrate that modification of the cellular redox-equilibrium occurs as a consequence of antioxidant nutrients intake (carotenoids, vitamine E and vitamine C) and that these nutrients play a role in the pigmentation of the skin without any UV exposure. We conducted a randomized, double-blind study in 20 healthy subjects to evaluate and to compare the efficacy of two mixtures of dietary antioxidants with regard to direct determination of melanin and carotenes by chromametry at selected skin sites and multiple reflection spectrometry from a 1 cm2 region of skin of different parts of the body. Efficacy was assessed by a significant improvement of these parameters, in comparison with measurements performed on the day of randomization, before dietary supplement intake. The formulations per capsule of study dietary supplements are: 13 mg of beta-carotene, 2 mg of lycopene, 5 mg of vitamine E and 30 mg of vitamine C (B13/L2) or 3 mg of beta-carotene, 3 mg of lycopene, 5 mg of vitamine E and 30 mg of vitamine C (B3/L3). A 8-week B13/L2-supplementation lead to a detectable carotenodermia whereas the B3/L3-supplementation not. Signicative increase of melanin concentrations in skin were found after 4, 5, 6 and 8 weeks of dietary antioxidant intake in both groups (p < 0.05). These results are discussed with regard to the redox control theory of melanocytes which regulates the tyrosinase activity.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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...

  4. Interaction and developmental activation of two neuroendocrine systems that regulate light-mediated skin pigmentation.

    PubMed

    Bertolesi, Gabriel E; Song, Yi N; Atkinson-Leadbeater, Karen; Yang, Jung-Lynn J; McFarlane, Sarah

    2017-07-01

    Lower vertebrates use rapid light-regulated changes in skin colour for camouflage (background adaptation) or during circadian variation in irradiance levels. Two neuroendocrine systems, the eye/alpha-melanocyte-stimulating hormone (α-MSH) and the pineal complex/melatonin circuits, regulate the process through their respective dispersion and aggregation of pigment granules (melanosomes) in skin melanophores. During development, Xenopus laevis tadpoles raised on a black background or in the dark perceive less light sensed by the eye and darken in response to increased α-MSH secretion. As embryogenesis proceeds, the pineal complex/melatonin circuit becomes the dominant regulator in the dark and induces lightening of the skin of larvae. The eye/α-MSH circuit continues to mediate darkening of embryos on a black background, but we propose the circuit is shut down in complete darkness in part by melatonin acting on receptors expressed by pituitary cells to inhibit the expression of pomc, the precursor of α-MSH. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Pharmacological induction of skin pigmentation unveils the neuroendocrine circuit regulated by light.

    PubMed

    Bertolesi, Gabriel E; Vazhappilly, Sherene T; Hehr, Carrie L; McFarlane, Sarah

    2016-03-01

    Light-regulated skin colour change is an important physiological process in invertebrates and lower vertebrates, and includes daily circadian variation and camouflage (i.e. background adaptation). The photoactivation of melanopsin-expressing retinal ganglion cells (mRGCs) in the eye initiates an uncharacterized neuroendocrine circuit that regulates melanin dispersion/aggregation through the secretion of alpha-melanocyte-stimulating hormone (α-MSH). We developed experimental models of normal or enucleated Xenopus embryos, as well as in situ cultures of skin of isolated dorsal head and tails, to analyse pharmacological induction of skin pigmentation and α-MSH synthesis. Both processes are triggered by a melanopsin inhibitor, AA92593, as well as chloride channel modulators. The AA9253 effect is eye-dependent, while functional data in vivo point to GABAA receptors expressed on pituitary melanotrope cells as the chloride channel blocker target. Based on the pharmacological data, we suggest a neuroendocrine circuit linking mRGCs with α-MSH secretion, which is used normally during background adaptation. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Autofluorescence of pigmented skin lesions using a pulsed UV laser with synchronized detection: clinical results

    NASA Astrophysics Data System (ADS)

    Cheng, Haynes P. H.; Svenmarker, Pontus; Xie, Haiyan; Tidemand-Lichtenberg, Peter; Jensen, Ole B.; Bendsoe, Niels; Svanberg, Katarina; Petersen, Paul Michael; Pedersen, Christian; Andersson-Engels, Stefan; Andersen, Peter E.

    2010-04-01

    We report preliminary clinical results of autofluorescence imaging of malignant and benign skin lesions, using pulsed 355 nm laser excitation with synchronized detection. The novel synchronized detection system allows high signal-tonoise ratio to be achieved in the resulting autofluorescence signal, which may in turn produce high contrast images that improve diagnosis, even in the presence of ambient room light. The synchronized set-up utilizes a compact, diode pumped, pulsed UV laser at 355 nm which is coupled to a CCD camera and a liquid crystal tunable filter. The excitation and image capture is sampled at 5 kHz and the resulting autofluorescence is captured with the liquid crystal filter cycling through seven wavelengths between 420 nm and 580 nm. The clinical study targets pigmented skin lesions and evaluates the prospects of using autofluorescence as a possible means in differentiating malignant and benign skin tumors. Up to now, sixteen patients have participated in the clinical study. The autofluorescence images, averaged over the exposure time of one second, will be presented along with histopathological results. Initial survey of the images show good contrast and diagnostic results show promising agreement based on the histopathological results.

  7. Spectrophotometer is useful for assessing vitiligo and chemical leukoderma severity by quantifying color difference with surrounding normally pigmented skin.

    PubMed

    Hayashi, M; Okamura, K; Araki, Y; Suzuki, M; Tanaka, T; Abe, Y; Nakano, S; Yoshizawa, J; Hozumi, Y; Inoie, M; Suzuki, T

    2018-05-01

    Acquired skin hypopigmentation has many etiologies, including autoimmune melanocyte destruction, skin aging, inflammation, and chemical exposure. Distinguishing lesions from normally pigmented skin is clinically important to precisely assess disease severity. However, no gold standard assessment method has been reported. We aimed to investigate whether spectrophotometers are useful for assessing vitiligo and rhododendrol (4-(4-hydroxyphenol)-2-butanol) (Rhododenol ® )-induced leukoderma disease severity by quantifying skin color. Mexameter ® MX18 and CM-700d spectrophotometer were used for assessing vitiligo/leukoderma by measuring melanin index, L*a*b* color space, and ΔE*ab value, which represents the color difference between two subjects and is calculated by the values of L*a*b*. MX18 and CM-700d can quantitatively distinguish vitiligo/leukoderma from normally pigmented skin based on melanin index. CM-700d consistently quantified the color of vitiligo/leukoderma lesions and surrounding normally pigmented skin in L*a*b* color spaces and ΔE*ab. ΔE*ab is well correlated with melanin index and clinical appearance. ΔE*ab has been frequently used in aesthetic dentistry; however, current study is the first to use it in the measurement of skin color. ΔE*ab seems to be a useful parameter to evaluate the color contrast between vitiligo/leukoderma and surrounding normally pigmented skin and can be used to evaluate disease severity and patient's quality of life. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Decreased ATP synthesis and lower pH may lead to abnormal muscle contraction and skin sensitivity in human skin.

    PubMed

    Kim, Eun Ju; Lee, Dong Hun; Kim, Yeon Kyung; Kim, Min-Kyoung; Kim, Jung Yun; Lee, Min Jung; Choi, Won Woo; Eun, Hee Chul; Chung, Jin Ho

    2014-12-01

    Sensitive skin represents hyperactive sensory symptoms showing exaggerated reactions in response to internal stimulants or external irritants. Although sensitive skin is a very common condition affecting an estimated 50% of the population, its pathophysiology remains largely elusive, particularly with regard to its metabolic aspects. The objective of our study was to investigate the pathogenesis of sensitive skin. We recruited healthy participants with 'sensitive' or 'non-sensitive' skin based on standardized questionnaires and 10% lactic acid stinging test, and obtained skin samples for microarray analysis and subsequent experiments. Microarray transcriptome profiling revealed that genes involved in muscle contraction, carbohydrate and lipid metabolism, and ion transport and balance were significantly decreased in sensitive skin. These altered genes could account for the abnormal muscle contraction, decreased ATP amount in sensitive skin. In addition, pain-related transcripts such as TRPV1, ASIC3 and CGRP were significantly up-regulated in sensitive skin, compared with non-sensitive skin. Our findings suggest that sensitive skin is closely associated with the dysfunction of muscle contraction and metabolic homeostasis. Copyright © 2014 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  9. Estimating melanin location in the pigmented skin lesions by hue-saturation-lightness color space values of dermoscopic images.

    PubMed

    Sakai, Hiroshi; Ando, Yoshimi; Ikinaga, Kuniko; Tanaka, Masaru

    2017-05-01

    The depth of melanin in the skin can be estimated roughly by observation of the color exhibited on dermoscopy. Currently, there are no objective methods to estimate it. The aim of the present study was to clarify the relationship between the depth of melanin in the skin and the color variation exhibited, and to objectively estimate the 3-D location of melanin in the pigmented skin lesions from dermoscopic images. Representative colors in dermoscopic images of acral compound nevus, Spitz nevus and blue nevus were evaluated by the subjectively perceived color on dermoscopy and objective values in hue-saturation-lightness color space values. Brown colors due to small quantities of superficial melanin in the skin had high saturation and low lightness values, whereas black colors due to large quantities of superficial melanin had low saturation and low lightness values. On the other hand, colors due to melanin in the dermis were perceived as blue-gray on dermoscopy, but extracted colors showed gray-brown hue and intermediate saturation and high lightness values. In all cases, extracted representative colors of pigmented skin lesions had similar hue values within the red-orange range. Objective estimation of the 3-D location of melanin in the pigmented skin lesions is possible by the saturation and lightness values of the colors extracted from dermoscopic images. Subjectively perceived colors of melanin, especially in the dermis, can be modified by the surrounding environment effect and blue color perception. © 2017 Japanese Dermatological Association.

  10. Teaching dermatoscopy of pigmented skin tumours to novices: comparison of analytic vs. heuristic approach.

    PubMed

    Tschandl, P; Kittler, H; Schmid, K; Zalaudek, I; Argenziano, G

    2015-06-01

    There are two strategies to approach the dermatoscopic diagnosis of pigmented skin tumours, namely the verbal-based analytic and the more visual-global heuristic method. It is not known if one or the other is more efficient in teaching dermatoscopy. To compare two teaching methods in short-term training of dermatoscopy to medical students. Fifty-seven medical students in the last year of the curriculum were given a 1-h lecture of either the heuristic- or the analytic-based teaching of dermatoscopy. Before and after this session, they were shown the same 50 lesions and asked to diagnose them and rate for chance of malignancy. Test lesions consisted of melanomas, basal cell carcinomas, nevi, seborrhoeic keratoses, benign vascular tumours and dermatofibromas. Performance measures were diagnostic accuracy regarding malignancy as measured by the area under the curves of receiver operating curves (range: 0-1), as well as per cent correct diagnoses (range: 0-100%). Diagnostic accuracy as well as per cent correct diagnoses increased by +0.21 and +32.9% (heuristic teaching) and +0.19 and +35.7% (analytic teaching) respectively (P for all <0.001). Neither for diagnostic accuracy (P = 0.585), nor for per cent correct diagnoses (P = 0.298) was a difference between the two groups. Short-term training of dermatoscopy to medical students allows significant improvement in diagnostic abilities. Choosing a heuristic or analytic method does not have an influence on this effect in short training using common pigmented skin lesions. © 2014 European Academy of Dermatology and Venereology.

  11. 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.

  12. The role of natural and UV-induced skin pigmentation on low-fluence IPL-induced side effects: a randomized controlled trial.

    PubMed

    Thaysen-Petersen, Daniel; Lin, Jennifer Y; Nash, Jf; Beerwerth, Frank; Wulf, Hans C; Philipsen, Peter A; Haedersdal, Merete

    2014-02-01

    The risk of adverse skin effects following light-based hair removal is greater in pigmented skin based on the theory of selective photothermolysis. Thus sunlight-induced pigment i.e., facultative pigmentation, increases the risk of adverse skin effects, perhaps disproportionately. The aim of this study was to evaluate the influence of constitutive and facultative skin pigmentation on low-fluence intense pulsed light (IPL)-induced adverse skin effects. Twenty-one subjects with Fitzpatrick skin type II-IV were enrolled. Two buttock blocks were randomized to receive 0 or 8 solar simulated ultraviolet radiation (UVR) exposures of consecutively increasing Standard Erythema Doses (2-4 SED). Each block was subdivided into four sites, randomized to receive IPL of 0, 7, 8, or 10 J/cm(2) , once a week for 3 weeks. Biopsies were taken 16-24 hours after the first IPL exposure and subjects were seen 1 and 4 weeks after the last IPL exposure. Outcome measures were: (i) skin reactions, (ii) pain, (iii) mRNA expression of pigment-markers microphthalmia-associated transcription factor (MITF) and pro-opiomelanocortin (POMC), and (iv) clinical appearance of biopsy wounds. Skin pigmentation increased after UVR (baseline median 13.8%, after UVR 28.1%, P = 0.0001) in all skin types. Subjects reported low pain intensities (median 1.5, scale 0-10) and experienced transient erythema immediately after IPL exposure. No persistent erythema, blisters, crusting, textual, or pigment changes were observed. The risk of erythema and pain intensities increased with IPL dose and skin pigmentation (P < 0.03). There was no difference in pain or skin reactions in skin with similar degree of natural and facultative pigmentation (P ≥ 0.104). Expression of cellular pigment-markers was not influenced by IPL exposure, neither in constitutive nor in facultative pigmented skin. Clinical appearance of biopsy wounds was unaffected by IPL exposure. The prevalence and intensity of low-fluence IPL

  13. 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.

  14. 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

  15. 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. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

    PubMed

    Paré, Bastien; Gros-Louis, François

    2017-07-26

    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.

  17. 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.

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

    PubMed

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

    2014-04-01

    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.

  19. Side effects from intense pulsed light: Importance of skin pigmentation, fluence level and ultraviolet radiation-A randomized controlled trial.

    PubMed

    Thaysen-Petersen, Daniel; Erlendsson, Andres M; Nash, J F; Beerwerth, Frank; Philipsen, Peter A; Wulf, Hans C; Paasch, Uwe; Haedersdal, Merete

    2017-01-01

    Intense pulsed light (IPL) is a mainstream treatment for hair removal. Side effects after IPL are known, but risk factors remain to be investigated. The objective of this study was to assess the contribution of skin pigmentation, fluence level, and ultraviolet radiation (UVR) on IPL-induced side effects. The study was a blinded, randomized intra-individual controlled trial including 16 healthy subjects with Fitzpatrick Skin Types (FST) II-V. Three test areas were each divided into four sites, randomized to a single IPL exposure of 22, 34, 46 J/cm 2 or triple stacking of 46 J/cm 2 . Areas were subsequently randomized to no UVR or single solar-simulated UVR exposure of 3 Standard Erythema Dose at 30 minutes or 24 hours after IPL. Each area had a corresponding control, resulting in 15 treatment sites. Follow-up visits were scheduled up to 4 weeks after IPL. Outcome measures were: (i) blinded clinical skin reactions; (ii) objectively measured erythema and pigmentation; (iii) pain measured by visual analog scale (VAS); (iv) histology (H&E, Fontana-Masson); and (v) mRNA-expression of p53. Fifteen subjects with FST II-IV completed the protocol. IPL induced a wide range of skin reactions, including erythema (87% of subjects), purpura (27%), blisters (20%), edema (13%), crusting (13%), hyper- (60%), and hypopigmentation (20%). Darker skin pigmentation and increasing IPL fluence were determinants for IPL-induced side effects (P ≤ 0.002), while a single exposure of UVR did not exacerbate side effects (P ≥ 0.180). Clinical findings were confirmed objectively by reflectance spectrometry and qualitatively by histological changes in skin architecture, inflammatory infiltration, and pigmentation. Marker of cellular DNA damage, that is, p53, did not increase after IPL (P ≥ 0.24). Skin pigmentation and IPL fluence are major determinants of side effects after IPL exposure, while a single exposure to three SED of UVR at 30 minutes or 24 hours after IPL

  20. Hair Color and Skin Color Together Influence Perceptions of Age, Health, and Attractiveness in Lightly-Pigmented, Young Women.

    PubMed

    Fink, Bernhard; Liebner, Katharina; Müller, Ann-Kathrin; Hirn, Thomas; McKelvey, Graham; Lankhof, John

    2018-05-17

    Research documents that even subtle changes in visible skin condition affect perceptions of age, health, and attractiveness. There is evidence that hair quality also affects the assessment of physical appearance, as variations in hair diameter, hair density, and hair style have systematic effects on perception. Here, we consider combined effects of hair color and skin color on the perception of female physical appearance. In two experiments, we digitally manipulated facial skin color of lightly-pigmented, young women, both between-subjects (Experiment 1) and within-subjects (Experiment 2), and investigated possible interactions with hair color in regard to age, health, and attractiveness perception. In both experiments, we detected hair color and skin color interaction effects on men's and women's assessments. For between-subjects comparisons, participants with lighter hair color were judged to be younger than those with darker shades; this effect was more pronounced in women with light skin color. No such effect was observed for within-subjects variation in skin color. Both experiments showed that smaller perceived contrast between hair color and skin color resulted in more positive responses. We conclude that hair color and facial skin color together have an effect on perceptions of female age, health, and attractiveness in young women, and we discuss these findings with reference to the literature on the role of hair and skin in the assessment of female physical appearance. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  1. 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.

  2. The Vitamin D–Folate Hypothesis as an Evolutionary Model for Skin Pigmentation: An Update and Integration of Current Ideas

    PubMed Central

    Lucock, Mark; Veysey, Martin; Beckett, Emma

    2018-01-01

    Vitamin D is unique in being generated in our skin following ultraviolet radiation (UVR) exposure. Ongoing research into vitamin D must therefore always consider the influence of UVR on vitamin D processes. The close relationship between vitamin D and UVR forms the basis of the “vitamin D–folate hypothesis”, a popular theory for why human skin colour has evolved as an apparent adaption to UVR environments. Vitamin D and folate have disparate sensitivities to UVR; whilst vitamin D may be synthesised following UVR exposure, folate may be degraded. The vitamin D–folate hypothesis proposes that skin pigmentation has evolved as a balancing mechanism, maintaining levels of these vitamins. There are several alternative theories that counter the vitamin D–folate hypothesis. However, there is significant overlap between these theories and the now known actions of vitamin D and folate in the skin. The focus of this review is to present an update on the vitamin D–folate hypothesis by integrating these current theories and discussing new evidence that supports associations between vitamin D and folate genetics, UVR, and skin pigmentation. In light of recent human migrations and seasonality in disease, the need for ongoing research into potential UVR-responsive processes within the body is also discussed. PMID:29710859

  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. The effect of environmental colour on the growth, metabolism, physiology and skin pigmentation of the carnivorous freshwater catfish Lophiosilurus alexandri.

    PubMed

    Costa, D C; Mattioli, C C; Silva, W S; Takata, R; Leme, F O P; Oliveira, A L; Luz, R K

    2017-03-01

    The growth, physiology and skin pigmentation of pacamã Lophiosilurus alexandri juveniles were evaluated in an experiment using different tank colours (white, yellow, green, blue, brown and black) over an 80 day period. The tank colours did not cause significant differences to final body mass, total length, survival rate, carcass composition (moisture, crude protein, ash, ether extract, calcium, phosphorus, energy), or to plasma protein, triglyceride and cholesterol values. Haematocrit values, however, were highest for fish kept in white tanks (ANOVA P < 0·05), while the greatest haemoglobin levels were recorded for fish kept in blue and brown tanks (P < 0·01). The concentrations of cortisol (P < 0·001) and glucose (P < 0·01) were the most in fish in the black tanks. Tank colour affected skin pigmentation significantly, with fish in white tanks having the highest values of L* (brightness) and the lowest values in blue and black tanks. L*, however, decreased in all treatments throughout the experiment. C* ab increased significantly over the course of the experiment in fish kept in white tanks. Similar increases of C* ab were recorded in the other treatments but to a lesser extent. The use of black tanks during the cultivation of L. alexandri caused stress and should be avoided. Cultivation in white and yellow tanks produced individuals with a pale skin colour, while cultivation in blue and black tanks resulted in juveniles with a darker and more pigmented skin. © 2016 The Fisheries Society of the British Isles.

  5. Non-invasive quantification of melanin in the stratum corneum: a novel indicator of skin lesions in pigmentation diseases.

    PubMed

    Matsunaka, H; Yamamoto, Y; Furukawa, F

    2017-02-01

    Skin melanin content is an important indicator for ascertaining the pathology of skin pigmentation diseases, but its analysis necessitates a biopsy or other means of collecting tissue, posing a considerable burden to the patient, and making it difficult to observe how a given skin site changes over time. Here, we aimed to establish a non-invasive method for quantifying the eumelanin and pheomelanin content of the stratum corneum. Sun-exposed and non-exposed samples from 10 healthy Japanese subjects were compared. We harvested the outermost layer of the stratum corneum by tape-stripping, considering the outer side of the forearm as a sun-exposed area, and medial side of the upper arm as a non-exposed area. Four additional subjects were included in the analysis of change in melanin content over time at the same skin site. The anterior lower leg received a single exposure to two minimal erythema dose sunlight, and the stratum corneum was harvested from the same site over a period of 20 weeks; we subsequently quantified the levels of eumelanin and pheomelanin using high-performance liquid chromatography. We were able to accurately quantify the eumelanin and pheomelanin contents of the stratum corneum, and to observe the evolution of the same skin site over time. Eumelanin levels were significantly higher in the sun-exposed area, with a peak in melanin observed after 11-15 weeks of sun exposure. This non-invasive method can serve as a marker for pathology of skin pigmentation diseases such as malignant tumors. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Accuracy of SIAscopy for pigmented skin lesions encountered in primary care: development and validation of a new diagnostic algorithm.

    PubMed

    Emery, Jon D; Hunter, Judith; Hall, Per N; Watson, Anthony J; Moncrieff, Marc; Walter, Fiona M

    2010-09-25

    Diagnosing pigmented skin lesions in general practice is challenging. SIAscopy has been shown to increase diagnostic accuracy for melanoma in referred populations. We aimed to develop and validate a scoring system for SIAscopic diagnosis of pigmented lesions in primary care. This study was conducted in two consecutive settings in the UK and Australia, and occurred in three stages: 1) Development of the primary care scoring algorithm (PCSA) on a sub-set of lesions from the UK sample; 2) Validation of the PCSA on a different sub-set of lesions from the same UK sample; 3) Validation of the PCSA on a new set of lesions from an Australian primary care population. Patients presenting with a pigmented lesion were recruited from 6 general practices in the UK and 2 primary care skin cancer clinics in Australia. The following data were obtained for each lesion: clinical history; SIAscan; digital photograph; and digital dermoscopy. SIAscans were interpreted by an expert and validated against histopathology where possible, or expert clinical review of all available data for each lesion. A total of 858 patients with 1,211 lesions were recruited. Most lesions were benign naevi (64.8%) or seborrhoeic keratoses (22.1%); 1.2% were melanoma. The original SIAscopic diagnostic algorithm did not perform well because of the higher prevalence of seborrhoeic keratoses and haemangiomas seen in primary care. A primary care scoring algorithm (PCSA) was developed to account for this. In the UK sample the PCSA had the following characteristics for the diagnosis of 'suspicious': sensitivity 0.50 (0.18-0.81); specificity 0.84 (0.78-0.88); PPV 0.09 (0.03-0.22); NPV 0.98 (0.95-0.99). In the Australian sample the PCSA had the following characteristics for the diagnosis of 'suspicious': sensitivity 0.44 (0.32-0.58); specificity 0.95 (0.93-0.97); PPV 0.52 (0.38-0.66); NPV 0.95 (0.92-0.96). In an analysis of lesions for which histological diagnosis was available (n = 111), the PCSA had a significantly

  7. Regulation of Human Skin Pigmentation in situ by Repetitive UV Exposure – Molecular Characterization of Responses to UVA and/or UVB

    PubMed Central

    Choi, Wonseon; Miyamura, Yoshinori; Wolber, Rainer; Smuda, Christoph; Reinhold, William; Liu, Hongfang; Kolbe, Ludger; Hearing, Vincent J.

    2012-01-01

    Ultraviolet (UV) radiation is a major environmental factor that affects pigmentation in human skin and can eventually result in various types of UV-induced skin cancers. The effects of various wavelengths of UV on melanocytes and other types of skin cells in culture have been studied but little is known about gene expression patterns in situ following in situe exposure of human skin to different types of UV (UVA and/or UVB). Paracrine factors expressed by keratinocytes and/or fibroblasts that affect skin pigmentation might be regulated differently by UV, as might their corresponding receptors expressed on melanocytes. To test the hypothesis that different mechanisms are involved in the pigmentary responses of the skin to different types of UV, we used immunohistochemical and whole human genome microarray analyses to characterize human skin in situ to examine how melanocyte-specific proteins and paracrine melanogenic factors are regulated by repetitive exposure to different types of UV compared with unexposed skin as a control. The results show that gene expression patterns induced by UVA or UVB are distinct, UVB eliciting dramatic increases in a large number of genes involved in pigmentation as well as in other cellular functions, while UVA had little or no effect on those. The expression patterns characterize the distinct responses of the skin to UVA or UVB, and identify several potential previously unidentified factors involved in UV-induced responses of human skin. PMID:20147966

  8. Colorimetric analysis of pigmented skin lesions: a pilot study with the Visi-Chroma VC-100 device.

    PubMed

    Vereecken, P; Mommaerts, M; Duez, C; Petein, M; Laporte, M; Hubinon, J-L; Heenen, M

    2006-01-01

    Definition of the colour of pigmented skin lesions (PSLs) with the naked eye remains subjective and may be influenced by lighting. This problem underlines the usefulness of instrumental assessments such as epiluminescence microscopy and colorimetric devices. We describe here a new method of colour analysis of PSLs with the Visi-Chroma VC-100 device, which illuminates the surface of the skin with white light-emitting diodes (LEDs) and analyses the reflected light by a red-green-blue (RGB) charge-coupled device (CCD) colour camera. Twenty-one PSLs to be excised for cosmetic or medical reasons were analysed by this device with clinicopathological correlation. This method is feasible and might be useful to assess the colour of PSLs and allow comparisons for changes over time. Further studies are needed to determine the usefulness of this device in clinical practice.

  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. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Effect of dietary carotenoids on vitamin A status and skin pigmentation in false tomato frogs (Dyscophus guineti).

    PubMed

    Brenes-Soto, Andrea; Dierenfeld, Ellen S

    2014-01-01

    Several species in captivity develop nutritional diseases including vitamin A deficiency; cases of this disease have been documented in amphibians, which may be linked to an insectivorous diet lacking in vitamin A or carotenoids. Adults and young of Dyscophus guineti were fed three diets over 9 weeks to evaluate effects on carotenoids and vitamin A status and skin pigmentation. Feeder crickets were either supplemented with soy oil (control, CON), soy oil enriched with β-carotene (BC) or mixed carotenoids (MIX) by direct injection of known dosages. Vitamin A from feeder crickets (measured as retinol) was higher in insects supplemented with both BC and MIX; (P=0.0001) and plasma retinol concentrations were significantly higher in frogs fed MIX (P<0.02). Results suggest that both false tomato frogs and feeder crickets could receive some provitamin A activity through consumption of diets supplemented with β-carotene, and xanthophylls like lutein and zeaxanthin. Pigmentation was evaluated weekly through the use of visual color charts, as well as quantitatively using a hand-held spectrophotometer. MIX diets had a significant effect on skin color values (P<0.0001), as well as on lightness (P=0.0005) and hue (P=0.0022). Results indicated that frogs fed with BC changed to yellower colors, and frogs fed with MIX changed to oranger colors. Visual color chart observations also scored significantly different between CON and MIX diets (P<0.05); the animals fed MIX also appeared oranger according to the qualitative observations. Dietary supplements with carotenoids resulted in color changes and higher circulating retinol concentrations in false tomato frogs. These pigments may provide provitamin A activity in diets, thus may support improved nutrition and health of captive-fed insectivorous amphibians. © 2014 Wiley Periodicals Inc.

  11. Photooxidative damage in retinal pigment epithelial cells via GRP78 and the protective role of grape skin polyphenols.

    PubMed

    Zhao, Zhao; Sun, Tao; Jiang, Yun; Wu, Lijiang; Cai, Xiangzhong; Sun, Xiaodong; Sun, Xiangjun

    2014-12-01

    Blue light induced oxidative damage and ER stress are related to the pathogenesis of age-related macular degeneration (AMD). However, the mechanism of blue light-induced damage remained obscure. The objective of this work is to assess the photooxidative damage to retinal pigment epithelial cells (RPE) and oxidation-induced changes in expression of ER stress associated apoptotic proteins, and investigate the mechanism underlying the protective effects of grape skin extracts. To mimic lipofuscin-mediated photooxidation in vivo, ARPE-19 cells that accumulated A2E, one of lipofuscin fluorophores, were used as a model system to investigate the mechanism of photooxidative damage and the protective effects of grape skin polyphenols. Exposure of A2E containing ARPE-19 cells to blue light resulted in significant apoptosis and increases in levels of GRP78, CHOP, p-JNK, Bax, cleaved caspase-9, and cleaved caspase-3, indicating that photooxidative damage to RPE cells is mediated by the ER-stress-induced intrinsic apoptotic pathway. Cells in which GRP78 had been knocked down with shRNA were more vulnerable to photooxidative damage. Pre-treatment of blue-light-exposed A2E containing ARPE-19 cells, with grape skin extracts, inhibited apoptosis, in a dose dependent manner. Knockdown GRP78 blocked the protective effect of grape skin extracts.

  12. Plasma immunoreactive beta-melanocyte-stimulating hormone and skin pigmentation in chronic renal failure.

    PubMed Central

    Smith, A G; Shuster, S; Comaish, J S; Plummer, N A; Thody, A J; Alvarez-Ude, F; Kerr, D N

    1975-01-01

    Plasma immunoreactive beta-melanocyte stimulating hormone (beta-MSH) concentrations were greatly increased in patients with chronic renal failure. There was no correlation between the severity of the renal failure or the degree of pigmentation and the plasma beta-MSH levels. PMID:1125653

  13. Human Adipose Mesenchymal Cells Inhibit Melanocyte Differentiation and the Pigmentation of Human Skin via Increased Expression of TGF-β1.

    PubMed

    Klar, Agnes S; Biedermann, Thomas; Michalak, Katarzyna; Michalczyk, Teresa; Meuli-Simmen, Claudia; Scherberich, Arnaud; Meuli, Martin; Reichmann, Ernst

    2017-12-01

    There is accumulating evidence that interactions between epidermal melanocytes and stromal cells play an important role in the regulation of skin pigmentation. In this study we established a pigmented dermo-epidermal skin model, melDESS, of human origin to investigate the effects of distinct stromal cells on melanogenesis. melDESS is a complex, clinically relevant skin equivalent composed of an epidermis containing both melanocytes and keratinocytes. Its dermal compartment consists either of adipose tissue-derived stromal cells, dermal fibroblasts (Fbs), or a mixture of both cell types. These skin substitutes were transplanted for 5 weeks on the backs of immuno-incompetent rats and analyzed. Gene expression and Western blot analyses showed a significantly higher expression of transforming growth factor-β1 by adipose tissue-derived stromal cells compared with dermal Fbs. In addition, we showed that melanocytes responded to the increased levels of transforming growth factor-β1 by down-regulating the expression of key melanogenic enzymes such as tyrosinase. This caused decreased melanin synthesis and, consequently, greatly reduced pigmentation of melDESS. The conclusions are of utmost clinical relevance, namely that adipose tissue-derived stromal cells derived from the hypodermis fail to appropriately interact with epidermal melanocytes, thus preventing the sustainable restoration of the patient's native skin color in bioengineered skin grafts. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  14. Video-based heart rate monitoring across a range of skin pigmentations during an acute hypoxic challenge.

    PubMed

    Addison, Paul S; Jacquel, Dominique; Foo, David M H; Borg, Ulf R

    2017-11-09

    The robust monitoring of heart rate from the video-photoplethysmogram (video-PPG) during challenging conditions requires new analysis techniques. The work reported here extends current research in this area by applying a motion tolerant algorithm to extract high quality video-PPGs from a cohort of subjects undergoing marked heart rate changes during a hypoxic challenge, and exhibiting a full range of skin pigmentation types. High uptimes in reported video-based heart rate (HR vid ) were targeted, while retaining high accuracy in the results. Ten healthy volunteers were studied during a double desaturation hypoxic challenge. Video-PPGs were generated from the acquired video image stream and processed to generate heart rate. HR vid was compared to the pulse rate posted by a reference pulse oximeter device (HR p ). Agreement between video-based heart rate and that provided by the pulse oximeter was as follows: Bias = - 0.21 bpm, RMSD = 2.15 bpm, least squares fit gradient = 1.00 (Pearson R = 0.99, p < 0.0001), with a 98.78% reporting uptime. The difference between the HR vid and HR p exceeded 5 and 10 bpm, for 3.59 and 0.35% of the reporting time respectively, and at no point did these differences exceed 25 bpm. Excellent agreement was found between the HR vid and HR p in a study covering the whole range of skin pigmentation types (Fitzpatrick scales I-VI), using standard room lighting and with moderate subject motion. Although promising, further work should include a larger cohort with multiple subjects per Fitzpatrick class combined with a more rigorous motion and lighting protocol.

  15. The Impact of Quantitative Data Provided by a Multi-spectral Digital Skin Lesion Analysis Device on Dermatologists'Decisions to Biopsy Pigmented Lesions.

    PubMed

    Farberg, Aaron S; Winkelmann, Richard R; Tucker, Natalie; White, Richard; Rigel, Darrell S

    2017-09-01

    BACKGROUND: Early diagnosis of melanoma is critical to survival. New technologies, such as a multi-spectral digital skin lesion analysis (MSDSLA) device [MelaFind, STRATA Skin Sciences, Horsham, Pennsylvania] may be useful to enhance clinician evaluation of concerning pigmented skin lesions. Previous studies evaluated the effect of only the binary output. OBJECTIVE: The objective of this study was to determine how decisions dermatologists make regarding pigmented lesion biopsies are impacted by providing both the underlying classifier score (CS) and associated probability risk provided by multi-spectral digital skin lesion analysis. This outcome was also compared against the improvement reported with the provision of only the binary output. METHODS: Dermatologists attending an educational conference evaluated 50 pigmented lesions (25 melanomas and 25 benign lesions). Participants were asked if they would biopsy the lesion based on clinical images, and were asked this question again after being shown multi-spectral digital skin lesion analysis data that included the probability graphs and classifier score. RESULTS: Data were analyzed from a total of 160 United States board-certified dermatologists. Biopsy sensitivity for melanoma improved from 76 percent following clinical evaluation to 92 percent after quantitative multi-spectral digital skin lesion analysis information was provided ( p <0.0001). Specificity improved from 52 percent to 79 percent ( p <0.0001). The positive predictive value increased from 61 percent to 81 percent ( p <0.01) when the quantitative data were provided. Negative predictive value also increased (68% vs. 91%, p<0.01), and overall biopsy accuracy was greater with multi-spectral digital skin lesion analysis (64% vs. 86%, p <0.001). Interrater reliability improved (intraclass correlation 0.466 before, 0.559 after). CONCLUSION: Incorporating the classifier score and probability data into physician evaluation of pigmented lesions led to both

  16. 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.

  17. Skin rash, headache and abnormal behaviour: unusual presentation of intracranial haemorrhage in dengue fever

    PubMed Central

    Wani, Abdul Majid; Mejally, Mousa Ali Al; Hussain, Waleed Mohd; Maimani, Wail Al; Hanif, Sadia; Khoujah, Amer Mohd; Siddiqi, Ahmad; Akhtar, Mubeena; Bafaraj, Mazen G; Fareed, Khurram

    2010-01-01

    Dengue viral infections are one of the most important mosquito borne diseases in the world. The dengue virus is a single stranded RNA virus belonging to the Flaviviridae family. There are four serotypes (DEN 1–4) classified according to biological and immunological criteria. Patients may be asymptomatic or their condition may give rise to undifferentiated fever, dengue fever, dengue haemorrhagic fever (DHF), or dengue shock syndrome. Annually, 100 million cases of dengue fever and half a million cases of DHF occur worldwide and 2.5 billion people are at risk. At present, dengue is endemic in 112 countries. Early recognition and prompt initiation of appropriate treatment are vital if disease related morbidity and mortality are to be limited. We present an interesting case of dengue fever with headache, skin rash and abnormal behaviour who had a massive intracranial haemorrhage with fatal outcome. PMID:22242067

  18. 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.

  19. Abnormal mural cell recruitment in lymphatic capillaries: a common pathological feature in chronic lymphedematous skin?

    PubMed

    Yu, Zi-You; Sun, Di; Luo, Yi; Liu, Ning-Fei

    2016-10-01

    This study aimed to explore the structural and functional characteristics of dermal lymphatic capillaries in patients with chronic LE, specifically focused on the mural cells that are associated with skin lymphatics. Forty-four patients (30 primary LE and 14 secondary LE) and eight healthy controls were enrolled in this study. Genetic analysis of the FOXC2 was performed in 18 patients with primary LE. Full-thickness skin was excised and immunohistologically stained for podoplanin and α-SMA. The proportions of α-SMA + Lv (α-SMA + Lv%) were calculated. Lymphatic vascular function was assessed by indocyanine green lymphography. Analysis of FOXC2 revealed two mutations in two patients with LDs. Histologically, thirty-nine patients exhibited increased α-SMA + mural cell coverage of lymphatic capillaries. The α-SMA + Lv% values in the superficial and deep dermis in patients with primary and secondary LE were significantly higher than in the control group. Compared with imaging findings in healthy limbs, in which the collecting lymphatics were clearly visualized, lymphedematous extremities all exhibited dermal backflow. Abnormal recruitment of mural cells in dermal lymphatic capillaries is a common pathological event in chronic LE, and may play a role in disease evolution. © 2016 John Wiley & Sons Ltd.

  20. Ursolic acid differentially modulates apoptosis in skin melanoma and retinal pigment epithelial cells exposed to UV-VIS broadband radiation.

    PubMed

    Lee, Yuan-Hao; Wang, Exing; Kumar, Neeru; Glickman, Randolph D

    2014-05-01

    The signaling pathways via mTOR (mammalian target of rapamycin) and AMPK (AMP-activated protein kinase) play key roles in transcription, translation and carcinogenesis, and may be activated by light exposure. These pathways can be modulated by naturally occurring compounds, such as the triterpenoid, ursolic acid (UA). Previously, the transcription factors p53 and NF-κB, which transactivate mitochondrial apoptosis-related genes, were shown to be differentially modulated by UA. UA-modulated apoptosis, following exposure to UV-VIS radiation (ultraviolet to visible light broadband radiation, hereafter abbreviated to UVR), is observed to correspond to differential levels of oxidative stress in retinal pigment epithelial (RPE) and skin melanoma (SM) cells. The cellular response to this phytochemical was characterized using western blot, flow cytometry, microscopy with reactive oxidative species probes MitoTracker and dihydroethidium, and membrane permeability assay. UA pretreatment potentiated cell cycle arrest and UVR-induced apoptosis selectively in SM cells while reducing photo-oxidative stress in the DNA of RPE cells presumably by antioxidant activity of UA. Mechanistically, the nuclear transportation of p65 and p53 was reduced by UA administration prior to UVR exposure while the levels of p65 and p53 nuclear transportation in SM cells were sustained at a substantially higher level. Finally, the mitochondrial functional assay showed that UVR induced the collapse of the mitochondrial membrane potential, and this effect was exacerbated by rapamycin or UA pretreatment in SM preferentially. These results were consistent with reduced proliferation observed in the clonogenic assay, indicating that UA treatment enhanced the phototoxicity of UVR, by modulating the activation of p53 and NF-κB and initiating a mitogenic response to optical radiation that triggered mitochondria-dependent apoptosis, particularly in skin melanoma cells. The study indicates that this compound

  1. Carbon dioxide laser ablation of dermatosis papulosa nigra: high satisfaction and few complications in patients with pigmented skin.

    PubMed

    Ali, Faisal R; Bakkour, Waseem; Ferguson, Janice E; Madan, Vishal

    2016-04-01

    Dermatosis papulosa nigra (DPN) is a common condition of pigmented skin. Whilst lesions are benign, they may be symptomatic or cosmetically disfiguring. Ablative lasers have previously been reported as a useful therapeutic modality in DPN. We report the largest case series to date of patients with DPN ablated with the carbon dioxide (CO2) laser. A retrospective case note review was conducted of all patients with DPN treated in our laser clinic in the last five years, and a post-treatment telephone survey was undertaken to assess patient satisfaction. Forty-five patients were identified, with a median age of 41 years (range 25-74 years), of whom 37 (82%) were female. The median number of treatments undertaken was three (range 1-10). Of the 18 respondents to the telephone survey, when asked to grade their satisfaction with the procedure out of 10, median response was 9.5 (range 6-10) with nine patients citing the maximum score of 10. All patients replied that their confidence had improved following the procedure and that they would recommend the treatment to other patients. Five respondents (28%) reported recurrence of a few lesions following CO2 laser ablation; the remaining 13 respondents (72%) reported no recurrence of DPN. No respondents reported any other post-procedural complications (including scarring, hypopigmentation and hyperpigmentation). We advocate use of the CO2 laser as a safe, convenient means of treating DPN, with a high degree of patient satisfaction, low recurrence rate and few complications.

  2. 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.

  3. 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. © 2013 The Authors, Animal Genetics © 2013 Stichting International Foundation for Animal Genetics.

  4. 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

  5. Pathogenic Cx31 is un/misfolded to cause skin abnormality via a Fos/JunB-mediated mechanism.

    PubMed

    Tang, Chengyuan; Chen, Xiang; Chi, Jingwei; Yang, Dawei; Liu, Shu; Liu, Mujun; Pan, Qian; Fan, Jianbing; Wang, Danling; Zhang, Zhuohua

    2015-11-01

    Mutations in connexin-31 (Cx31) are associated with multiple human diseases, including familial erythrokeratodermia variabilis (EKV). The pathogenic mechanism of EKV-associated Cx31 mutants remains largely elusive. Here, we show that EKV-pathogenic Cx31 mutants are un/misfolded and temperature sensitive. In Drosophila, expression of pathogenic Cx31, but not wild-type Cx31, causes depigmentation and degeneration of ommatidia that are rescued by expression of either dBip or dHsp70. Ectopic expression of Cx31 in mouse skin results in skin abnormalities resembling human EKV. The affected tissues show remarkable disrupted gap junction formation and significant upregulation of chaperones Bip and Hsp70 as well as AP-1 proteins c-Fos and JunB, in addition to molecular signatures of skin diseases. Consistently, c-Fos, JunB, Bip and Hsp70 are strikingly higher in keratinocytes of EKV patients than their matched control individuals. Furthermore, a druggable AP-1 inhibitory small molecule suppresses skin phenotype and pathological abnormalities of transgenic Cx31 mice. The study suggests that Cx31 mutant proteins are un/misfolded to cause EKV likely via an AP-1-mediated mechanism and identifies a small molecule with therapeutic potential of the disease. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Synchrotron-based ν-XRF mapping and μ-FTIR microscopy enable to look into the fate and effects of tattoo pigments in human skin.

    PubMed

    Schreiver, Ines; Hesse, Bernhard; Seim, Christian; Castillo-Michel, Hiram; Villanova, Julie; Laux, Peter; Dreiack, Nadine; Penning, Randolf; Tucoulou, Remi; Cotte, Marine; Luch, Andreas

    2017-09-12

    The increasing prevalence of tattoos provoked safety concerns with respect to particle distribution and effects inside the human body. We used skin and lymphatic tissues from human corpses to address local biokinetics by means of synchrotron X-ray fluorescence (XRF) techniques at both the micro (μ) and nano (ν) scale. Additional advanced mass spectrometry-based methodology enabled to demonstrate simultaneous transport of organic pigments, heavy metals and titanium dioxide from skin to regional lymph nodes. Among these compounds, organic pigments displayed the broadest size range with smallest species preferentially reaching the lymph nodes. Using synchrotron μ-FTIR analysis we were also able to detect ultrastructural changes of the tissue adjacent to tattoo particles through altered amide I α-helix to β-sheet protein ratios and elevated lipid contents. Altogether we report strong evidence for both migration and long-term deposition of toxic elements and tattoo pigments as well as for conformational alterations of biomolecules that likely contribute to cutaneous inflammation and other adversities upon tattooing.

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

    PubMed

    Park, Jong Il; Lee, Ha Yeon; Lee, Ji Eun; Myung, Cheol Hwan; Hwang, Jae Sung

    2016-07-06

    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.

  9. 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

  10. mHealth App for Risk Assessment of Pigmented and Nonpigmented Skin Lesions-A Study on Sensitivity and Specificity in Detecting Malignancy.

    PubMed

    Thissen, Monique; Udrea, Andreea; Hacking, Michelle; von Braunmuehl, Tanja; Ruzicka, Thomas

    2017-12-01

    With the advent of smartphone devices, an increasing number of mHealth applications that target melanoma identification have been developed, but none addresses the general context of melanoma and nonmelanoma skin cancer identification. In this study a smartphone application using fractal and classical image analysis for the risk assessment of skin lesions is systematically evaluated to determine its sensitivity and specificity in the diagnosis of melanoma and nonmelanoma skin cancer along with actinic keratosis and Bowen's disease. In the Department of Dermatology, Catharina Hospital Eindhoven, The Netherlands, 341 melanocytic and nonmelanocytic lesions were imaged using SkinVision app; 239 underwent histopathological examination, while the rest of 102 lesions were clinically diagnosed as clearly benign and not removed. The algorithm has been calibrated using the images of the first 233 lesions. The calibrated version of the algorithm was used in a subset of 108 lesions, and the obtained results were compared with the medical findings. On the 108 cases used for evaluation the algorithm scored 80% sensitivity and 78% specificity in detecting (pre)malignant conditions. Although less accurate than the dermatologist's clinical eye, the app may offer support to other professionals who are less familiar with differentiating between benign and malignant lesions. An mHealth application for the risk assessment of skin lesions was evaluated. It adds value to diagnosis tools of its type by taking into consideration pigmented and nonpigmented lesions all together and detecting signs of malignancy with high sensitivity.

  11. Abnormal brain activation in excoriation (skin-picking) disorder: evidence from an executive planning fMRI study

    PubMed Central

    Odlaug, Brian L.; Hampshire, Adam; Chamberlain, Samuel R.; Grant, Jon E.

    2016-01-01

    Background Excoriation (skin-picking) disorder (SPD) is a relatively common psychiatric condition whose neurobiological basis is unknown. Aims To probe the function of fronto-striatal circuitry in SPD. Method Eighteen participants with SPD and 15 matched healthy controls undertook an executive planning task (Tower of London) during functional magnetic resonance imaging (fMRI). Activation during planning was compared between groups using region of interest and whole-brain permutation cluster approaches. Results The SPD group exhibited significant functional underactivation in a cluster encompassing bilateral dorsal striatum (maximal in right caudate), bilateral anterior cingulate and right medial frontal regions. These abnormalities were, for the most part, outside the dorsal planning network typically activated by executive planning tasks. Conclusions Abnormalities of neural regions involved in habit formation, action monitoring and inhibition appear involved in the pathophysiology of SPD. Implications exist for understanding the basis of excessive grooming and the relationship of SPD with putative obsessive–compulsive spectrum disorders. PMID:26159604

  12. 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.

  13. 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.

  14. 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. © 2012 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  15. 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.

  16. 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

  17. Vitamin D intake needed to maintain target serum 25-hydroxyvitamin D concentrations in participants with low sun exposure and dark skin pigmentation is substantially higher than current recommendations.

    PubMed

    Hall, Laura M; Kimlin, Michael G; Aronov, Pavel A; Hammock, Bruce D; Slusser, James R; Woodhouse, Leslie R; Stephensen, Charles B

    2010-03-01

    Cutaneous cholecalciferol synthesis has not been considered in making recommendations for vitamin D intake. Our objective was to model the effects of sun exposure, vitamin D intake, and skin reflectance (pigmentation) on serum 25-hydroxyvitamin D (25[OH]D) in young adults with a wide range of skin reflectance and sun exposure. Four cohorts of participants (n = 72 total) were studied for 7-8 wk in the fall, winter, spring, and summer in Davis, CA [38.5 degrees N, 121.7 degrees W, Elev. 49 ft (15 m)]. Skin reflectance was measured using a spectrophotometer, vitamin D intake using food records, and sun exposure using polysulfone dosimeter badges. A multiple regression model (R(2) = 0.55; P < 0.0001) was developed and used to predict the serum 25(OH)D concentration for participants with low [median for African ancestry (AA)] and high [median for European ancestry (EA)] skin reflectance and with low [20th percentile, approximately 20 min/d, approximately 18% body surface area (BSA) exposed] and high (80th percentile, approximately 90 min/d, approximately 35% BSA exposed) sun exposure, assuming an intake of 200 iu/d (5 ug/d). Predicted serum 25(OH)D concentrations for AA individuals with low and high sun exposure in the winter were 24 and 42 nmol/L and in the summer were 40 and 60 nmol/L. Corresponding values for EA individuals were 35 and 60 nmol/L in the winter and in the summer were 58 and 85 nmol/L. To achieve 25(OH)D > or =75 nmol/L, we estimate that EA individuals with high sun exposure need 1300 iu/d vitamin D intake in the winter and AA individuals with low sun exposure need 2100-3100 iu/d year-round.

  18. Toward in vivo diagnosis of skin cancer using multimode imaging dermoscopy: (II) molecular mapping of highly pigmented lesions

    NASA Astrophysics Data System (ADS)

    Vasefi, Fartash; MacKinnon, Nicholas; Farkas, Daniel L.

    2014-03-01

    We have developed a multimode imaging dermoscope that combines polarization and hyperspectral imaging with a computationally rapid analytical model. This approach employs specific spectral ranges of visible and near infrared wavelengths for mapping 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 that are prone to inaccuracies due to over-modeling. Various human skin measurements including a melanocytic nevus, and venous occlusion conditions were investigated and compared with other ratiometric spectral imaging approaches. Access to the broad range of hyperspectral data in the visible and near-infrared range allows our algorithm to flexibly use different wavelength ranges for chromophore estimation while minimizing melanin-hemoglobin optical signature cross-talk.

  19. Cyclic Alopecia and Abnormal Epidermal Cornification in Zdhhc13-Deficient Mice Reveal the Importance of Palmitoylation in Hair and Skin Differentiation.

    PubMed

    Liu, Kai-Ming; Chen, Yi-Ju; Shen, Li-Fen; Haddad, Amir N S; Song, I-Wen; Chen, Li-Ying; Chen, Yu-Ju; Wu, Jer-Yuarn; Yen, Jeffrey J Y; Chen, Yuan-Tsong

    2015-11-01

    Many biochemical pathways involved in hair and skin development have not been investigated. Here, we reported on the lesions and investigated the mechanism underlying hair and skin abnormalities in Zdhhc13(skc4) mice with a deficiency in DHHC13, a palmitoyl-acyl transferase encoded by Zdhhc13. Homozygous affected mice showed ragged and dilapidated cuticle of the hair shaft (CUH, a hair anchoring structure), poor hair anchoring ability, and premature hair loss at early telogen phase of the hair cycle, resulting in cyclic alopecia. Furthermore, the homozygous affected mice exhibited hyperproliferation of the epidermis, disturbed cornification, fragile cornified envelope (CE, a skin barrier structure), and impaired skin barrier function. Biochemical investigations revealed that cornifelin, which contains five palmitoylation sites at cysteine residues (C58, C59, C60, C95, and C101), was a specific substrate of DHHC13 and that it was absent in the CUH and CE structures of the affected mice. Furthermore, cornifelin levels were markedly reduced when two palmitoylated cysteines were replaced with serine (C95S and C101S). Taken together, our results suggest that DHHC13 is important for hair anchoring and skin barrier function and that cornifelin deficiency contributes to cyclic alopecia and skin abnormalities in Zdhhc13(skc4) mice.

  20. Performance of a computer-aided digital dermoscopic image analyzer for melanoma detection in 1,076 pigmented skin lesion biopsies.

    PubMed

    Del Rosario, Francis; Farahi, Jessica M; Drendel, Jesse; Buntinx-Krieg, Talayesa; Caravaglio, Joseph; Domozych, Renee; Chapman, Stephanie; Braunberger, Taylor; Dellavalle, Robert P; Norris, David A; Fathi, Ramin; Alkousakis, Theodore

    2018-05-01

    Digital dermoscopic image analysis of pigmented skin lesions (PSLs) has become increasingly popular, despite its unclear clinical utility. Unbiased, high-powered studies investigating the efficacy of commercially available systems are limited. To investigate the diagnostic performance of the FotoFinder Mole-Analyzer in assessing PSLs for cutaneous melanoma. In this 15-year retrospective study, the histopathologies of 1076 biopsied PSLs among a total of 2500 imaged PSLs were collected. The biopsied PSLs were categorized as benign or malignant (cutaneous melanoma) based on histopathology. Analyzer scores (0-1.00) for these PSLs were obtained and grouped according to histopathology. At an optimized cutoff score of 0.50, a sensitivity of 56% and a specificity of 74% were achieved. The area under the receiver operating characteristics curve was 0.698, indicating poor accuracy as a diagnostic tool. This study had a retrospective design and involved only a single institution. Our study reveals a low sensitivity of the scoring function of this digital dermoscopic image analyzer for detecting cutaneous melanomas. Physicians must apply keen clinical judgment when using such devices in the screening of suspicious PSLs. Copyright © 2017 American Academy of Dermatology, Inc. All rights reserved.

  1. [Dermatology and skin color].

    PubMed

    Petit, Antoine

    2010-09-01

    Melanin is the pigment that is responsible for skin, hair and eye colours. Genetics and sun exposure are the two key factors that determine skin pigmentation. In dermatology, skin colours is significant, not only for semiology and diagnosis, but also for epidemiology and wounds healing.

  2. Inhibition of melanosome transfer results in skin lightening.

    PubMed

    Seiberg, M; Paine, C; Sharlow, E; Andrade-Gordon, P; Costanzo, M; Eisinger, M; Shapiro, S S

    2000-08-01

    The chemical basis of melanogenesis is well documented, but the mechanism of melanosome transfer and the regulation of pigmentation by keratinocyte-melanocyte interactions are not well understood. Therefore we examined the effects of serine protease inhibitors on skin pigmentation and found that the protease-activated receptor 2, expressed on keratinocytes, may regulate pigmentation via keratinocyte-melanocyte interactions. Here we show that modulation of protease-activated receptor 2 activation affects melanosome transfer into keratinocytes, resulting in changes in pigment production and deposition. SLIGRL, the protease-activated receptor 2 activating peptide, enhanced melanosome ingestion by keratinocytes, thus increasing pigment deposition. RWJ-50353, a serine protease inhibitor, led to reduced pigment deposition in melanocytes and depigmentation. Electron microscopy studies illustrated an accumulation of immature melanosomes inside melanocytes and abnormal dendrite dynamics in RWJ-50353-treated epidermal equivalents. RWJ-50353 induced a visible and dose-dependent skin lightening effect in the dark-skinned Yucatan swine. Examinations by electron microscopy indicated that the in vivo transfer of melanosomes from melanocytes to keratinocytes was affected. Our data suggest that modulation of keratinocyte-melanocyte interactions via the protease-activated receptor 2 pathway affects melanosome transfer. The use of RWJ-50353 to modulate protease-activated receptor 2 activation could lead to a new class of depigmenting agents.

  3. 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.

  4. Compound Heterozygous Desmoplakin Mutations Result in a Phenotype with a Combination of Myocardial, Skin, Hair, and Enamel Abnormalities

    PubMed Central

    Mahoney, Mỹ 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

    2014-01-01

    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. PMID:19924139

  5. Abnormalities of hair structure and skin histology derived from CRISPR/Cas9-based knockout of phospholipase C-delta 1 in mice.

    PubMed

    Liu, Yu-Min; Liu, Wei; Jia, Jun-Shuang; Chen, Bang-Zhu; Chen, Heng-Wei; Liu, Yu; Bie, Ya-Nan; Gu, Peng; Sun, Yan; Xiao, Dong; Gu, Wei-Wang

    2018-05-25

    Hairless mice have been widely applied in skin-related researches, while hairless pigs will be an ideal model for skin-related study and other biomedical researches because of the similarity of skin structure with humans. The previous study revealed that hairlessness phenotype in nude mice is caused by insufficient expression of phospholipase C-delta 1 (PLCD1), an essential molecule downstream of Foxn1, which encouraged us to generate PLCD1-deficient pigs. In this study, we plan to firstly produce PLCD1 knockout (KO) mice by CRISPR/Cas9 technology, which will lay a solid foundation for the generation of hairless PLCD1 KO pigs. Generation of PLCD1 sgRNAs and Cas 9 mRNA was performed as described (Shao in Nat Protoc 9:2493-2512, 2014). PLCD1-modified mice (F0) were generated via co-microinjection of PLCD1-sgRNA and Cas9 mRNA into the cytoplasm of C57BL/6J zygotes. Homozygous PLCD1-deficient mice (F1) were obtained by intercrossing of F0 mice with the similar mutation. PLCD1-modified mice (F0) showed progressive hair loss after birth and the genotype of CRISPR/Cas9-induced mutations in exon 2 of PLCD1 locus, suggesting the sgRNA is effective to cause mutations that lead to hair growth defect. Homozygous PLCD1-deficient mice (F1) displayed baldness in abdomen and hair sparse in dorsa. Histological abnormalities of the reduced number of hair follicles, irregularly arranged and curved hair follicles, epidermal hyperplasia and disturbed differentiation of epidermis were observed in the PLCD1-deficient mice. Moreover, the expression level of PLCD1 was significantly decreased, while the expression levels of other genes (i.e., Krt1, Krt5, Krt13, loricrin and involucrin) involved in the differentiation of hair follicle were remarkerably increased in skin tissues of PLCD1-deficient mice. In conclusion, we achieve PLCD1 KO mice by CRISPR/Cas9 technology, which provide a new animal model for hair development research, although homozygotes don't display completely hairless

  6. Dermatoscopic findings of pigmented purpuric dermatosis.

    PubMed

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

    2016-01-01

    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. The aim of this study is to investigate the dermatoscopic findings of pigmented purpuric dermatosis. 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. 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). 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.

  7. 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

  8. Red pigment from Lithospermum erythrorhizon by supercritical CO2 extraction.

    PubMed

    Lee, Hwa-Young; Kim, Yoon-Jung; Kim, Eun-Jung; Song, Young-Keun; Byun, Sang Yo

    2008-01-01

    In this study, a stable red pigment was prepared from Lithospermum erythrorhizon via supercritical carbon dioxide extraction. The optimal extraction conditions were 400 bar and 60 degrees C. The patch tests indicated that up to 10% of the red pigment was acceptable from a skin irritation standpoint. According to the results of the CIE LAB chromaticity test, the color difference was acceptable when compared to commercial synthetic red pigments. The light-illuminated color stability test indicated that the pigment was more stable than the red pigment extracted with ethanol. The higher stability was also demonstrated in the DPPH antioxidant activity test. The supercritical red pigment harbored elevated amounts of shikonin and derivatives, and appears to be usable as a stable red pigment for cosmetic color products.

  9. Stages of Skin Cancer

    MedlinePlus

    ... of skin biopsies: Shave biopsy : A sterile razor blade is used to “shave-off” the abnormal-looking ... the surface of the skin with a small blade. Electrodesiccation and curettage : The tumor is cut from ...

  10. Skin Cancer Treatment

    MedlinePlus

    ... of skin biopsies: Shave biopsy : A sterile razor blade is used to “shave-off” the abnormal-looking ... the surface of the skin with a small blade. Electrodesiccation and curettage : The tumor is cut from ...

  11. Pigmented basal cell carcinoma: increased melanin or increased melanocytes?

    PubMed

    Brankov, Nikoleta; Prodanovic, Edward M; Hurley, M Yadira

    2016-12-01

    Studies on the precise cause of increased melanization in pigmented basal cell carcinomas (BCC) are limited. We aimed to determine whether the cause of melanization is from increased number of melanocytes or increased melanin pigment, and if there is a difference in the number of melanocytes on different sun-exposed locations. A retrospective review of 45 skin biopsies from January 2011 to February 2011 was performed; 30 were diagnosed as pigmented BCC and 15 as non-pigmented BCC. Immunohistochemistry for MART-1 (melanoma-associated antigen recognized by T-cell 1)/Melan-A (clone M2-7610 + M2-9E3; Leica Microsystems Inc. Buffalo Grove, IL, USA) from Biocare Medical (Concord, CA, USA) was performed on all biopsies. Associations between histopathologic features, number of melanocytes, location, and specific diagnoses were analyzed by Mann-Whitney U test. The mean melanocyte count per high powered field in pigmented BCCs from sun-exposed skin was 101.9 and from intermittently sun-exposed skin was 122.5, as compared to the controls (nodular non-pigmented BCC) of 27.4 (p = 0.002) and 34.9 (p = 0.002), respectively. Pigmented BCCs have a higher mean melanocyte count as compared to non-pigmented BCCs irrespective of location. Therefore, the pigment is not only due to increased melanin, but also due to increased melanocytes. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Pigmentation after single and multiple UV-exposures depending on UV-spectrum.

    PubMed

    Ravnbak, M H; Wulf, H C

    2007-04-01

    Minimal pigmentation dose (MMD) after a single UV-exposure is well investigated. Whereas only few studies have established MMD after multiple UV-exposures and mainly in fair-skinned persons. The purpose of this study was to establish MMD 1 week after, respectively, one and five UV-exposures in volunteers with a large variation in constitutive pigmentation. A total of 52 volunteers (skin Types II-V) had skin pigmentation quantified by reflectance spectroscopy. They were UV-exposed on the back for 1 and 5 days using a Solar Simulator, narrowband UVB, broadband UVA and UVA1. For all sources a higher dose was needed the more pigmented the skin, except for UVA1. After one UV-exposure, we found a significant positive linear correlation between UV-dose to one MMD, skin type and pre-exposure skin pigmentation. After five UV-exposures the positive linear correlation between UV-dose and MMD and skin type was only significant for narrow band UVB, pre-exposure skin pigmentation was significant also for Solar Simulator. For UVA and particularly UVA1 the MMD was independent of pre-exposure pigmentation. The number of SED to MMD is therefore almost the same for very fair-skinned and dark-skinned persons. Pre-exposure pigmentation was clearly more predictive of MMD than skin type. 50% of MMD equals a pigmentation increase of 1%. The shorter the wavelengths the higher the SED to produce MMD. Solar was the least melanogenic and UVA1 the most melanogenic. For the UVB-sources a higher dose was needed the more pigmented the skin. For UVA the MMD was independent of pre-exposure pigmentation.

  13. Pseudoephedrine may cause "pigmenting" fixed drug eruption.

    PubMed

    Ozkaya, Esen; Elinç-Aslan, Meryem Sevinç

    2011-05-01

    Fixed drug eruption (FDE) is a distinctive drug eruption characterized by recurrent well-defined lesions in the same location each time the responsible drug is taken. Two different clinical forms have been described: the common classic pigmenting form and the rare nonpigmenting form. Nonpigmenting FDE is mainly characterized by symmetrical large erythematous plaques and the dermal histopathologic reaction pattern. Pseudoephedrine is known as the major inducer of nonpigmenting FDE. Pigmenting FDE from pseudoephedrine has not been reported previously. Here, the first case of pseudoephedrine-induced pigmenting FDE is reported, showing the characteristic features of classic pigmenting FDE such as asymmetry, normal-sized lesions, and the epidermodermal histopathologic reaction pattern. Moreover, a positive occlusive patch-test reaction to pseudoephedrine could be demonstrated on postlesional FDE skin for the first time.

  14. Surgical Management of Iatrogenic Pigment Dispersion Glaucoma.

    PubMed

    Mierlo, Camille Van; Pinto, Luis Abegão; Stalmans, Ingeborg

    2015-01-01

    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. Case-series. Patients with IOP elevation and clinical signs of pigment dispersion were screened for a diagnosis of iatrogenic IOL-related pigment dispersion. 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. 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.

  15. 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

  16. Overview of plant pigments

    USDA-ARS?s Scientific Manuscript database

    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...

  17. 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.

  18. 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

  19. Characterization of skin abnormalities in a mouse model of osteogenesis imperfecta using high resolution magnetic resonance imaging and Fourier transform infrared imaging spectroscopy.

    PubMed

    Canuto, H C; Fishbein, K W; Huang, A; Doty, S B; Herbert, R A; Peckham, J; Pleshko, N; Spencer, R G

    2012-01-01

    Evaluation of the skin phenotype in osteogenesis imperfecta (OI) typically involves biochemical measurements, such as histologic or biochemical assessment of the collagen produced from biopsy-derived dermal fibroblasts. As an alternative, the current study utilized non-invasive magnetic resonance imaging (MRI) microscopy and optical spectroscopy to define biophysical characteristics of skin in an animal model of OI. MRI of skin harvested from control, homozygous oim/oim and heterozygous oim/+ mice demonstrated several differences in anatomic and biophysical properties. Fourier transform infrared imaging spectroscopy (FT-IRIS) was used to interpret observed MRI signal characteristics in terms of chemical composition. Differences between wild-type and OI mouse skin included the appearance of a collagen-depleted lower dermal layer containing prominent hair follicles in the oim/oim mice, accounting for 55% of skin thickness in these. The MRI magnetization transfer rate was lower by 50% in this layer as compared to the upper dermis, consistent with lower collagen content. The MRI transverse relaxation time, T2, was greater by 30% in the dermis of the oim/oim mice compared to controls, consistent with a more highly hydrated collagen network. Similarly, an FT-IRIS-defined measure of collagen integrity was 30% lower in the oim/oim mice. We conclude that characterization of phenotypic differences between the skin of OI and wild-type mice by MRI and FT-IRIS is feasible, and that these techniques provide powerful complementary approaches for the analysis of the skin phenotype in animal models of disease. Copyright © 2011 John Wiley & Sons, Ltd.

  20. Hairless pigmented guinea pigs: a new model for the study of mammalian pigmentation.

    PubMed

    Bolognia, J L; Murray, M S; Pawelek, J M

    1990-09-01

    A stock of hairless pigmented guinea pigs was developed to facilitate studies of mammalian pigmentation. This stock combines the convenience of a hairless animal with a pigmentary system that is similar to human skin. In both human and guinea pig skin, active melanocytes are located in the basal layer of the interfollicular epidermis. Hairless albino guinea pigs on an outbred Hartley background (CrI:IAF/HA(hr/hr)BR; designated hr/hr) were mated with red-haired guinea pigs (designated Hr/Hr). Red-haired heterozygotes from the F1 generation (Hr/hr) were then mated with each other or with hairless albino guinea pigs. The F2 generation included hairless pigmented guinea pigs that retained their interfollicular epidermal melanocytes and whose skin was red-brown in color. Following UV irradiation, there was an increase in cutaneous pigmentation as well as an increase in the number of active epidermal melanocytes. An additional strain of black hairless guinea pigs was developed using black Hr/Hr animals and a similar breeding scheme. These two strains should serve as useful models for studies of the mammalian pigment system.

  1. Chronic Diarrhea and Skin Hyperpigmentation: A New Association

    PubMed Central

    Al Qoaer, Khaled; Al Mehaidib, Ali; Shabib, Sohail; Banemai, Mohammed

    2008-01-01

    Background/Aims: The objective of this study was to describe patients with chronic diarrhea and abnormal skin hyperpigmentation with distinct distribution. Methods: This is a retrospective review of children who presented with diarrhea and skin hyperpigmentation. The clinical presentation, laboratory investigations as well as endoscopic and histological data were reviewed. Results: Seven patients with chronic diarrhea had abnormal skin hyperpigmentation with distinct distribution and presented in the first two months of life. Six patients had other features such as abnormal hair and facial dysmorphism. Mental retardation was reported in one patient. Consanguinity was positive in six patients, and there was family history of consanguinity in four patients, with two patients being siblings. No significant immunodeficiency was reported. Intestinal biopsies were obtained in six patients and showed active chronic inflammation in three patients, partial villous atrophy in two patients, and eosinophilic infiltrate with mild villous atrophy in one patient. Colonic biopsies showed mild focal colitis in three patients and mild colitis with eosinophilic infiltrate in one patient. Skin biopsies showed a greater number of melanophagies with fibrosis of papillary derma in two patients but skin biopsy was normal in one patient. The hair of two patients was analyzed by electron microscopy, which showed an abnormal pattern with decreased pigmentation and diameter; however, its chemical analysis was normal. Two other patients had trichorrhexis nodosa, but no abnormalities were seen in one patient. Chromosomal number was normal in three patients. One patient died because of sepsis, and only one patient was dependent on total parenteral nutrition. Conclusions: We believe that this association might represent a new syndrome with an autosomal recessive inheritance that warrants further studies. PMID:19568536

  2. Hydroxychloroquine-induced pigmentation in patients with systemic lupus erythematosus: a case-control study.

    PubMed

    Jallouli, Moez; Francès, Camille; Piette, Jean-Charles; Huong, Du Le Thi; Moguelet, Philippe; Factor, Cecile; Zahr, Noël; Miyara, Makoto; Saadoun, David; Mathian, Alexis; Haroche, Julien; De Gennes, Christian; Leroux, Gaelle; Chapelon, Catherine; Wechsler, Bertrand; Cacoub, Patrice; Amoura, Zahir; Costedoat-Chalumeau, Nathalie

    2013-08-01

    Hydroxychloroquine-induced pigmentation is not a rare adverse effect. Our data support the hypothesis that hydroxychloroquine-induced pigmentation is secondary to ecchymosis or bruising. To describe the clinical features and outcome of hydroxychloroquine (HCQ)-induced pigmentation in patients with systemic lupus erythematosus (SLE). In a case-control study conducted at a French referral center for SLE and antiphospholipid syndrome, 24 patients with SLE, with a diagnosis of HCQ-induced pigmentation, were compared with 517 SLE controls treated with HCQ. The primary outcome was the clinical features of HCQ-induced pigmentation. Skin biopsies were performed on 5 patients, both in healthy skin and in the pigmented lesions. The statistical associations of HCQ-induced pigmentation with several variables were calculated using univariate and multivariate analyses. Among the 24 patients, skin pigmentation appeared after a median HCQ treatment duration of 6.1 years (range, 3 months-22 years). Twenty-two patients (92%) reported that the appearance of pigmented lesions was preceded by the occurrence of ecchymotic areas, which gave way to a localized blue-gray or brown pigmentation that persisted. Twenty-three patients (96%) had at least 1 condition predisposing them to easy bruising. Results from skin biopsies performed on 5 patients showed that the median concentration of iron was significantly higher in biopsy specimens of pigmented lesions compared with normal skin (4115 vs 413 nmol/g; P < .001). Using multivariate logistic regression, we found that HCQ-induced pigmentation was independently associated with previous treatment with oral anticoagulants and/or antiplatelet agents and with higher blood HCQ concentration. Hydroxychloroquine-induced pigmentation is not a rare adverse effect of HCQ. Our data support the hypothesis that HCQ-induced pigmentation is secondary to ecchymosis or bruising.

  3. Insights from zebrafish on human pigment cell disease and treatment.

    PubMed

    Cooper, Cynthia D

    2017-11-01

    Black pigment cells, melanocytes, arise early during development from multipotent neural crest cells. Melanocytes protect human skin from DNA damaging sunrays and provide color for hair, eyes, and skin. Several disorders and diseases originate from these cells, including the deadliest skin cell cancer, melanoma. Thus, melanocytes are critical for a healthy life and for protecting humans from disease. Due to the ease of visualizing pigment cells through transparent larvae skin and conserved roles for zebrafish melanophore genes to mammalian melanocyte genes, zebrafish larvae offer a biologically relevant model for understanding pigment cell development and disease in humans. This review discusses our current knowledge of melanophore biology and how zebrafish are contributing to improving how diseases of melanocytes are understood and treated in humans. Developmental Dynamics 246:889-896, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  4. 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.

  5. 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.

  6. Depigmented skin and phantom color measurements for realistic prostheses.

    PubMed

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

    2014-02-01

    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. Data was analyzed from 20 of 32 recruited vitiligo study participants. Diffuse reflectance spectroscopy measurements were made from depigmented skin and adjacent pigmented skin, then compared with 66 pigmented polydimethylsiloxane phantoms to determine pigment concentrations in turbid media for making realistic facial prostheses. 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). 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. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. 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.

  8. Filaggrin 2 deficiency results in abnormal cell-cell adhesion in the cornified cell layers and causes peeling skin syndrome type A.

    PubMed

    Mohamad, Janan; Sarig, Ofer; Godsel, Lisa M; Peled, Alon; Malchin, Natalia; Bochner, Ron; Vodo, Dan; Rabinowitz, Tom; Pavlovsky, Mor; Taiber, Shahar; Fried, Maya; Eskin-Schwartz, Marina; Assi, Siwar; Shomron, Noam; Uitto, Jouni; Koetsier, Jennifer L; Bergman, Reuven; Green, Kathleen J; Sprecher, Eli

    2018-05-11

    Peeling skin syndromes form a large and heterogeneous group of inherited disorders characterized by superficial detachment of the epidermal cornified cell layers, often associated with inflammatory features. Here we report on a consanguineous family featuring non-inflammatory peeling of the skin exacerbated by exposure to heat and mechanical stress. Whole exome sequencing revealed a homozygous nonsense mutation in FLG2, encoding filaggrin 2, which co-segregated with the disease phenotype in the family. The mutation was found to result in decreased FLG2 RNA levels as well almost total absence of filaggrin 2 in the patient epidermis. Filaggrin 2 was found to be expressed throughout the cornified cell layers and to co-localize with corneodesmosin which plays a crucial role in maintaining cell-cell adhesion in this region of the epidermis. Absence of filaggrin 2 in the patient skin was associated with markedly decreased corneodesmosin expression, which may contribute to the peeling phenotype displayed by the patients. Accordingly, using the dispase dissociation assay, we showed that FLG2 down-regulation interferes with keratinocyte cell-cell adhesion. Of particular interest, this effect was aggravated by temperature elevation, consistent with the clinical phenotype. Restoration of CDSN levels by ectopic expression rescued cell-cell adhesion.Taken together, the present data suggest that filaggrin 2 is essential for normal cell-cell adhesion in the cornified cell layers. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  9. Fish pigmentation and the melanocortin system.

    PubMed

    Cal, Laura; Suarez-Bregua, Paula; Cerdá-Reverter, José Miguel; Braasch, Ingo; Rotllant, Josep

    2017-09-01

    The melanocortin system is a complex neuroendocrine signaling mechanism involved in numerous physiological processes in vertebrates, including pigmentation, steroidogenesis and metabolic control. This review focuses at one of its most fascinating function in fish, its regulatory role in the control of pigmentation, in which the melanocortin 1 receptor (Mc1r), its agonist α-melanocyte stimulating hormone (α-Msh), and the endogenous antagonist agouti signaling protein (Asip1) are the main players. Functional control of Mc1r, which is highly expressed in fish skin and whose activation stimulates melanin production and melanosome dispersion in fish melanophores, is considered a key mechanism for vertebrate pigment phenotypes. The α-Msh peptide, the most documented Mc1r agonist involved in pigmentation, is produced in the pituitary gland, activating melanin synthesis by binding to Mc1r in fish melanophores. Finally, Asip1 is the putative factor for establishing the evolutionarily conserved dorso-ventral pigment pattern found across vertebrates. However, we are just starting to understand how other melanocortin system components are acting in this complex regulatory network. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. 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.

    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 tomore » 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.« less

  11. Pericentric inversion of chromosome 11 (p14.3q21) associated with developmental delays, hypopigmented skin lesions and abnormal brain MRI findings - a new case report

    SciTech Connect

    Zachor, D.A.; Lofton, M.

    1994-09-01

    We report 3 year old male, referred for evaluation of developmental delays. Pregnancy was complicated by oligohydramnios, proteinuria and prematurity. Medical history revealed: bilateral inguinal hernia, small scrotal sac, undescended testes, developmental delays and behavioral problems. The child had: microcephaly, facial dysmorphic features, single palmar creases, hypopigmented skin lesions of variable size, intermittent exotropia and small retracted testes. Neurological examination was normal. Cognitive level was at the average range with mild delay in his adaptive behavior. Expressive language delays and severe articulation disorder were noted, as well as clumsiness, poor control and precision of gross and fine motor skills. Chromosomalmore » analysis of peripheral leukocytes indicated that one of the number 11 chromosomes had undergone a pericentric inversion with breakpoints on the short (p) arm at band p14.3 and the long (q) arm at band q21. An MRI of the brain showed mild delay in myelinization pattern of white matter. Chromosome 11 inversion in other sites was associated with Beckwith-Wiedemann syndrome and several malignancies. To our knowledge this is the first description of inv(11)(p14.3q21) that is associated with microcephaly, dysmorphic features, hypopigmented skin lesions and speech delay. This inversion may disrupt the expression of the involved genes. However, additional cases with the same cytogenetic anomaly are needed to explore the phenotypic significance of this disorder.« less

  12. 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.

  13. Meiotic abnormalities

    SciTech Connect

    NONE

    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.

  14. Inhibitors of Intracellular Signaling Pathways that Lead to Stimulated Epidermal Pigmentation: Perspective of Anti-Pigmenting Agents

    PubMed Central

    Imokawa, Genji; Ishida, Koichi

    2014-01-01

    Few anti-pigmenting agents have been designed and developed according to their known hyperpigmentation mechanisms and corresponding intracellular signaling cascades. Most anti-pigmenting agents developed so far are mechanistically involved in the interruption of constitutional melanogenic mechanisms by which skin color is maintained at a normal and unstimulated level. Thus, owing to the difficulty of confining topical application to a specific hyperpigmented skin area, potent anti-pigmenting agents capable of attenuating the natural unstimulated pigmentation process have the risk of leading to hypopigmentation. Since intracellular signaling pathways within melanocytes do not function substantially in maintaining normal skin color and are activated only by environmental stimuli such as UV radiation, specifically down-regulating the activation of melanogenesis to the constitutive level would be an appropriate strategy to develop new potent anti-pigmenting agents with a low risk of hypopigmentation. In this article, we review the hyperpigmentation mechanisms and intracellular signaling pathways that lead to the stimulation of melanogenesis. We also discuss a screening and evaluation system to select candidates for new anti-melanogenic substances by focusing on inhibitors of endothelin-1 or stem cell factor-triggered intracellular signaling cascades. From this viewpoint, we show that extracts of the herbs Withania somnifera and Melia toosendan and the natural chemicals Withaferin A and Astaxanthin are new candidates for potent anti-pigmenting substances that avoid the risk of hypopigmentation. PMID:24823877

  15. 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. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. 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

  17. 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. © 2016. Published by The Company of Biologists Ltd.

  18. Scalded skin syndrome

    MedlinePlus

    ... infection. IV fluids are also given to prevent dehydration. Much of the body's fluid is lost through open skin. Moist compresses ... result include: Abnormal level of fluids in the body causing ... or electrolyte imbalance Poor temperature control (in young ...

  19. The peripheral clock regulates human pigmentation.

    PubMed

    Hardman, Jonathan A; Tobin, Desmond J; Haslam, Iain S; Farjo, Nilofer; Farjo, Bessam; Al-Nuaimi, Yusur; Grimaldi, Benedetto; Paus, Ralf

    2015-04-01

    Although the regulation of pigmentation is well characterized, it remains unclear whether cell-autonomous controls regulate the cyclic on-off switching of pigmentation in the hair follicle (HF). As human HFs and epidermal melanocytes express clock genes and proteins, and given that core clock genes (PER1, BMAL1) modulate human HF cycling, we investigated whether peripheral clock activity influences human HF pigmentation. We found that silencing BMAL1 or PER1 in human HFs increased HF melanin content. Furthermore, tyrosinase expression and activity, as well as TYRP1 and TYRP2 mRNA levels, gp100 protein expression, melanocyte dendricity, and the number gp100+ HF melanocytes, were all significantly increased in BMAL1 and/or PER1-silenced HFs. BMAL1 or PER1 silencing also increased epidermal melanin content, gp100 protein expression, and tyrosinase activity in human skin. These effects reflect direct modulation of melanocytes, as BMAL1 and/or PER1 silencing in isolated melanocytes increased tyrosinase activity and TYRP1/2 expression. Mechanistically, BMAL1 knockdown reduces PER1 transcription, and PER1 silencing induces phosphorylation of the master regulator of melanogenesis, microphthalmia-associated transcription factor, thus stimulating human melanogenesis and melanocyte activity in situ and in vitro. Therefore, the molecular clock operates as a cell-autonomous modulator of human pigmentation and may be targeted for future therapeutic strategies.

  20. Effects of glycolic acid chemical peeling on facial pigment deposition: evaluation using novel computer analysis of digital-camera-captured images.

    PubMed

    Kakudo, Natsuko; Kushida, Satoshi; Suzuki, Kenji; Kusumoto, Kenji

    2013-12-01

    Chemical peeling is becoming increasingly popular for skin rejuvenation in dermatological cosmetic medicine. However, the improvements seen with chemical peeling are often very minor, and it is difficult to conduct a quantitative assessment of pre- and post-treatment appearance. We report the pre- and postpeeling effects for facial pigment deposition using a novel computer analysis method for digital-camera-captured images. Glycolic acid chemical peeling was performed a total of 5 times at 2-week intervals in 23 healthy women. We conducted a computer image analysis by utilizing Robo Skin Analyzer CS 50 and Clinical Suite 2.1 and then reviewed each parameter for the area of facial pigment deposition pre- and post-treatment. Parameters were pigmentation size and four pigmentation categories: little pigmentation and three levels of marked pigmentation (Lv1, 2, and 3) based on detection threshold. Each parameter was measured, and the total area of facial pigmentation was calculated. The total area of little pigmentation and marked pigmentation (Lv1) was significantly reduced. On the other hand, a significant difference was not observed for the total area of marked pigmentation Lv2 and Lv3. This suggests that glycolic acid chemical peeling has an effect on small facial pigment disposition or has an effect on light pigment deposition. As the Robo Skin Analyzer is useful for objectively quantifying and analyzing minor changes in facial skin, it is considered to be an effective tool for accumulating treatment evidence in the cosmetic and esthetic skin field. © 2013 Wiley Periodicals, Inc.

  1. Familial grouped pigmentation of the retinal pigment epithelium.

    PubMed Central

    de Jong, P T; Delleman, J W

    1988-01-01

    Grouped pigmentation of the retinal pigment epithelium was found in a father and his son. They had a normal resting potential on the electro-oculogram, but the son had a lower normal light rise. We believe this is the first description of familial grouped pigmentation. Images PMID:3390419

  2. 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

  3. Congenital Abnormalities

    MedlinePlus

    ... tube defects. However, there is also a genetic influence to this type of congenital anomaly. Unknown Causes The vast majority of congenital abnormalities have no known cause. This is particularly troubling for parents who plan to have more children, because there is no way to predict if ...

  4. A prospective, split-face, double-blinded, randomized study of the efficacy and safety of a fractional 1064-nm Q-switched Nd:YAG laser for photoaging-associated mottled pigmentation in Asian skin.

    PubMed

    Won, Kwang Hee; Lee, Sang Hyung; Lee, Mi Hye; Rhee, Do-Young; Yeo, Un-Cheol; Chang, Sung Eun

    2016-11-01

    Laser toning using low-fluence 1064-nm Q-switched neodymium-doped yttrium aluminum laser (QSNY) has gained popularity in the treatment of photoaging-associated mottled pigmentation (PMP). However, hypopigmentation or lack of efficacy has been reported depending on the fluences used. To compare a novel fractional 1064-nm QSNY with conventional 1064-nm QSNY for the treatment of photoaging-associated mottled pigmentary lesions except epidermal lesions of lentigines and freckles through a randomized, split-face, double-blind study. Thirteen Asian women were treated every week for 6 weeks with fractional 1064-nm QSNY on one side of the face and conventional 1064-nm QSNY on the other side. We evaluated the pigmentation area and severity index (PSI), melanin index, erythema index, and the patient's global assessment of improvement. At three months post-treatment, the PSI score improved compared with baseline, by 14.48% on the conventional 1064-nm QSNY side and 21.81% on the fractional 1064-nm QSNY side. Both groups showed improvements in the melanin index. Both fractional 1064-nm QSNY and strictly low-fluence conventional 1064-nm QSNY are moderately effective against PMP and other photoaging signs. Fractional laser toning shows better subjective outcomes than conventional toning.

  5. Volumetric Visualization of Human Skin

    NASA Astrophysics Data System (ADS)

    Kawai, Toshiyuki; Kurioka, Yoshihiro

    We propose a modeling and rendering technique of human skin, which can provide realistic color, gloss and translucency for various applications in computer graphics. Our method is based on volumetric representation of the structure inside of the skin. Our model consists of the stratum corneum and three layers of pigments. The stratum corneum has also layered structure in which the incident light is reflected, refracted and diffused. Each layer of pigment has carotene, melanin or hemoglobin. The density distributions of pigments which define the color of each layer can be supplied as one of the voxel values. Surface normals of upper-side voxels are fluctuated to produce bumps and lines on the skin. We apply ray tracing approach to this model to obtain the rendered image. Multiple scattering in the stratum corneum, reflective and absorptive spectrum of pigments are considered. We also consider Fresnel term to calculate the specular component for glossy surface of skin. Some examples of rendered images are shown, which can successfully visualize a human skin.

  6. 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.

  7. Ultraviolet B irradiation of the mouse eye induces pigmentation of the skin more strongly than does stress loading, by increasing the levels of prohormone convertase 2 and α-melanocyte-stimulating hormone.

    PubMed

    Hiramoto, K; Yamate, Y; Kobayashi, H; Ishii, M; Sato, E F; Inoue, M

    2013-01-01

    In previous studies, we made the unexpected finding that in mice, ultraviolet (UV)B irradiation of the eye increased the concentration of α-melanocyte-stimulating hormone (α-MSH) in plasma, and systemically stimulated epidermal melanocytes. To compare the extent of the pigmentation induced by social and restraint stress (which activate the hippocampus-pituitary system) with that induced by UVB irradiation. DBA/2 and sham-operated or hypophysectomized DBA/2 mice were subjected to local UVB exposure using a sunlamp directed at the eye, and two types of stress (social and restraint) were imposed. UVB irradiation of the eye or exposure to stress loading both increased the number of Dopa-positive melanocytes in the epidermis, and hypophysectomy strongly inhibited the UVB-induced and stress-induced stimulation of melanocytes. Irradiation of the eye caused a much greater increase in dopamine than did the stress load. Both UVB eye irradiation and stress increased the blood levels of α-MSH and adrenocorticotropic hormone (ACTH). In addition, the increase in plasma α-MSH was greater in animals subjected to UVB eye irradiation than in those subjected to stress loading, whereas the reverse occurred for plasma ACTH. UVB irradiation to the eye and stress loading increased the expression of prohormone convertase (PC)1/3 and PC2 in the pituitary gland. The increase in expression of pituitary PC2 was greater in animals subjected to UVB eye irradiation than to stress, whereas no difference was seen between the two groups for the increase in PC1/3. UVB eye irradiation exerts a stronger effect on pigmentation than stress loading, and is related to increased levels of α-MSH and PC2. © The Author(s). CED © 2012 British Association of Dermatologists.

  8. PIGMENTS OF THE RETINA

    PubMed Central

    Wald, George

    1936-01-01

    1. Visual purple from the sea robin, sea bass, and scup is almost identical spectroscopically with that from frogs. The interrelations of this pigment with vitamin A and retinene are also the same as in the frog. 2. In strong acids or at pH > 11, the visual yellow of sea robin retinas is converted irreversibly into a pH indicator, yellow in acid and almost colorless in alkaline solution. Unlike neutral visual yellow, the indicator is not removed to form either vitamin A or visual purple. In the ammoniacal retina the reversion of visual yellow itself to purple is accelerated. 3. The combined pigment epithelium and choroid layer in these fishes contain vitamin A, flavine, and an unidentified xanthophyll. PMID:19872983

  9. Skin lightening preparations and the hydroquinone controversy.

    PubMed

    Draelos, Zoe Diana

    2007-01-01

    Skin lightening preparations are widely used in dermatology by persons of all Fitzpatrick skin types. Fitzpatrick skin types I-III require local pigment lightening for the treatment of hormonally induced melasma and postinflammatory hyperpigmentation caused by acne and trauma. Fitzpatrick skin types IV and darker have an even greater need for skin lightening for social reasons, as well as pigmentary changes that occur around the eyes, in the intertriginous areas, following dermatitis, or with acne and trauma. The gold standard dermatologic agent for skin lightening was hydroquinone, until regulatory agencies in Japan, Europe, and most recently in the United States questioned the safety of this substance. This has encouraged research into alternative agents to inhibit skin pigmentation such as retinoids, mequinol, azelaic acid, arbutin, kojic acid, aleosin, licorice extract, ascorbic acid, soy proteins, and N-acetyl glucosamine. The efficacy and safety of each of these ingredients is examined as possible topical alternatives to hydroquinone.

  10. 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

  11. Environment and the skin

    SciTech Connect

    Suskind, R.R.

    The effects of the environment on skin are surveyed. Specific patterns of adverse skin response can be characterized by morphological, physiological, and biochemical features. Cutaneous defenses and adaptations of the skin are discussed. Dermal resiliency, epidermal and pigment components, neural components, immunobiological processes, and the epidermal barrier are examined. Percutaneous absorption is reviewed. Environmental factors that cause adverse skin reactions include water, salts of heavy metals, hydrocarbons, solvents, lipids, aromatics, esters, ultraviolet light, and various modalities of ionizing radiation. Pathologic patterns and reaction sites are discussed in terms of inflammatory, allergic, benign epidermal, eccrine sweat gland, and pilosebaceous reactions, pigmentarymore » disturbances, cancer, and blood vessel changes. Although critical epidemiologic data are limited, cutaneous illnesses constitute a significant segment of occupational disease. Recommendations for further research are summarized. 42 references.« less

  12. Lack of tumour pigmentation in conjunctival melanoma is associated with light iris colour and worse prognosis.

    PubMed

    Brouwer, Niels J; Marinkovic, Marina; Luyten, Gregorius P M; Shields, Carol L; Jager, Martine J

    2018-05-18

    To investigate whether differences in iris colour, skin colour and tumour pigmentation are related to clinical outcome in conjunctival melanoma. Data of 70 patients with conjunctival melanoma from the Leiden University Medical Center (Leiden, The Netherlands) and 374 patients from the Wills Eye Hospital (Philadephia, USA) were reviewed. The relation between iris colour, skin colour and tumour pigmentation versus clinical parameters and outcome was investigated using univariate and multivariate regression analyses. A light iris colour (blue, grey, green) was present in 261 (59%) patients and a dark colour (hazel, brown) in 183 (41%). A low tumour pigmentation was detected in 130 (40%) and a high pigmentation in 197 (60%) patients. Low tumour pigmentation was associated with light iris colour (p=0.021) but not related to skin colour (p=0.92). In univariate analysis, neither iris nor skin colour was related to clinical outcome, while a low tumour pigmentation was related to metastasis formation (HR 2.37, p=0.004) and death (HR 2.42, p=0.020). In multivariate analysis, low tumour pigmentation was related to the development of recurrences (HR 1.63, p=0.043), metastasis formation (HR 2.48, p=0.004) and death (HR 2.60, p=0.014). Lightly pigmented tumours occurred especially in individuals with lightly coloured irises. While iris colour or skin colour was not significantly related to clinical outcome, a low tumour pigmentation was related to a worse outcome in patients with conjunctival melanoma. The amount and type of melanin in conjunctival melanocytes may be involved in the pathogenesis and behaviour of selected conjunctival melanoma. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  13. Effect of wavelength on cutaneous pigment using pulsed irradiation

    SciTech Connect

    Sherwood, K.A.; Murray, S.; Kurban, A.K.

    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 beenmore » 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.« less

  14. Treatment Options for Nonmelanoma Skin Cancer

    MedlinePlus

    ... of skin biopsies: Shave biopsy : A sterile razor blade is used to “shave-off” the abnormal-looking ... the surface of the skin with a small blade. Electrodesiccation and curettage : The tumor is cut from ...

  15. [A case of skin autograft for skin ulcers in ichthyosis].

    PubMed

    Li, Shiwei; Yang, Xiaodong; Liu, Lijun; Tang, Xueyang

    2017-10-28

    Ichthyosis refers to a group of skin diseases characterized by abnormal keratinization of the epidermis, resulting in dryness, roughness and scale of the skin. A girl with ichthyosis, who presented with skin ulcers and infection of the right dorsal foot, was admitted to our department. An autologous razor-thin skin grafting procedure was performed to repair the skin ulcers after debridement and vacuum sealing drain. After 8 months of follow-up, both the donor and recipient site healed well and there were no newly formed ulcers or infections. Although the skin quality of ichthyosis is poor, the lesion area can still be used as donor or recipient cite.

  16. Skin sensitivity and skin microbiota: Is there a link?

    PubMed

    Seite, Sophie; Misery, Laurent

    2018-05-21

    Sensitive skin is defined by the occurrence of unpleasant sensations, accompanied or not by erythema, in response to stimuli which normally should not provoke such sensations and that cannot be linked to skin disease. Even if its pathophysiology is not completely known, hyper-reactivity of the cutaneous nervous system associated with an abnormal skin barrier has been hypothesized as a primary culprit including more recently a role of the cutaneous microbiota. The objective of this short review is to discuss the relationship between the skin microbiota, skin sensitivity and the skin barrier function. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  17. Abnormal placentation.

    PubMed

    Bauer, Samuel T; Bonanno, Clarissa

    2009-04-01

    Abnormal placentation poses a diagnostic and treatment challenge for all providers caring for pregnant women. As one of the leading causes of postpartum hemorrhage, abnormal placentation involves the attachment of placental villi directly to the myometrium with potentially deeper invasion into the uterine wall or surrounding organs. Surgical procedures that disrupt the integrity of uterus, including cesarean section, dilatation and curettage, and myomectomy, have been implicated as key risk factors for placenta accreta. The diagnosis is typically made by gray-scale ultrasound and confirmed with magnetic resonance imaging, which may better delineate the extent of placental invasion. It is critical to make the diagnosis before delivery because preoperative planning can significantly decrease blood loss and avoid substantial morbidity associated with placenta accreta. Aggressive management of hemorrhage through the use of uterotonics, fluid resuscitation, blood products, planned hysterectomy, and surgical hemostatic agents can be life-saving for these patients. Conservative management, including the use of uterine and placental preservation and subsequent methotrexate therapy or pelvic artery embolization, may be considered when a focal accreta is suspected; however, surgical management remains the current standard of care.

  18. Aging of the Hair Follicle Pigmentation System

    PubMed Central

    Tobin, Desmond J

    2009-01-01

    Skin and hair phenotypes are powerful cues in human communication. They impart much information, not least about our racial, ethnic, health, gender and age status. In the case of the latter parameter, we experience significant change in pigmentation in our journey from birth to puberty and through to young adulthood, middle age and beyond. The hair follicle pigmentary unit is perhaps one of our most visible, accessible and potent aging sensors, with marked dilution of pigment intensity occurring long before even subtle changes are seen in the epidermis. This dichotomy is of interest as both skin compartments contain melanocyte subpopulations of similar embryologic (i.e., neural crest) origin. Research groups are actively pursuing the study of the differential aging of melanocytes in the hair bulb versus the epidermis and in particular are examining whether this is in part linked to the stringent coupling of follicular melanocytes to the hair growth cycle. Whether some follicular melanocyte subpopulations are affected, like epidermal melanocytes, by UV irradiation is not yet clear. A particular target of research into hair graying or canities is the nature of the melanocyte stem compartment and whether this is depleted due to reactive oxygen species-associated damage, coupled with an impaired antioxidant status, and a failure of melanocyte stem cell renewal. Over the last few years, we and others have developed advanced in vitro models and assay systems for isolated hair follicle melanocytes and for intact anagen hair follicle organ culture which may provide research tools to elucidate the regulatory mechanisms of hair follicle pigmentation. Long term, it may be feasible to develop strategies to modulate some of these aging-associated changes in the hair follicle that impinge particularly on the melanocyte populations. PMID:20927229

  19. Dermoscopy of Pigmented Actinic Keratosis of the Face: A Study of 232 Cases.

    PubMed

    Kelati, A; Baybay, H; Moscarella, E; Argenziano, G; Gallouj, S; Mernissi, F Z

    2017-11-01

    The diagnosis of pigmented actinic keratosis (PAK) is often challenging because of overlapping features with lentigo maligna. To investigate dermoscopic patterns of PAK according to their different evolutionary stages, and to correlate the pattern with clinical characteristics of the patients. Descriptive and analytical study of 232 PAK. Dermoscopic patterns were divided into two categories: the follicule surroundings' abnormalities (FSA) and follicular keratosis' abnormalities (FKA). FSA and FKA dermoscopic patterns were related to male gender, except for star-like appearance, double white clods and dermoscopic horn (p≤0.04). Rhomboidal, annular granular pattern, gray halo, white circle and double clods were dermoscopic pattern significantly related to xeroderma pigmentosum's type of skin. Based on the evolutionary stages of PAK, the jelly sign was significantly related to thin patches of PAK. Central crusts and scales were related to thick plaques and the star-like appearance to hypertrophic PAK. The presence of 2 or more dermoscopic signs in both FSA and FKA was noticed in 99.1% of lesions. The dermoscopic diagnosis of PAK vary according to the evolutionary stages of the disease, this will increase the diagnosis accuracy, with therapeutic implications. Copyright © 2017 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. 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.

  1. Tattoo Pigments Are Observed in the Kupffer Cells of the Liver Indicating Blood-Borne Distribution of Tattoo Ink.

    PubMed

    Sepehri, Mitra; Sejersen, Tobias; Qvortrup, Klaus; Lerche, Catharina M; Serup, Jørgen

    2017-01-01

    Tattoo pigments are deposited in the skin and known to distribute to regional lymph nodes. Tattoo pigments are small particles and may be hypothesized to reach the blood stream and become distributed to peripheral organs. This has not been studied in the past. The aim of the study was to trace tattoo pigments in internal organs in mice extensively tattooed with 2 different tattoo ink products. Three groups of mice were studied, i.e., 10 tattooed black, 10 tattooed red, and 5 untreated controls. They were tattooed on the entire back with commercial tattoo inks, black and red. Mice were sacrificed after 1 year. Samples were isolated from tattooed skin, lymph nodes, liver, spleen, kidney, and lung. Samples were examined for deposits of tattoo pigments by light microscopy and transmission electron microscopy (TEM). TEM identified intracellular tattoo pigments in the skin and in lymph nodes. TEM in both groups of tattooed mice showed tattoo pigment deposits in the Kupffer cells in the liver, which is a new observation. TEM detected no pigment in other internal organs. Light microscopy showed dense pigment in the skin and in lymph nodes but not in internal organs. The study demonstrated black and red tattoo pigment deposits in the liver; thus, tattoo pigment distributed from the tattooed skin via the blood stream to this important organ of detoxification. The finding adds a new dimension to tattoo pigment distribution in the body, i.e., as observed via the blood in addition to the lymphatic pathway. © 2017 S. Karger AG, Basel.

  2. 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

  3. Efficacy and safety of topical depigmenting agent in healthy human fair skin female volunteers: A single-arm study.

    PubMed

    Shah, Saurabh; Chew, Soon-Keong

    2017-11-28

    Skin hyperpigmentation is the darkening of skin due to the increased production of melanin in the body. To evaluate the efficacy and safety of a botanical-based Rosa E pigmentation serum in healthy fair skin female volunteers with wrinkles, skin tone, and pigmentation. This was a single-arm, open label study conducted in healthy Indian females; 18 subjects aged 30-55, having fair Caucasian-like skin with at least 2 dark skin pigments with facial wrinkles diagnosed by dermatologist were selected. Rosa E pigmentation serum was applied twice a day for 84 days. Effect was evaluated by (i) instrumental technique (spectrophotometer ® 2600D), (ii) clinically by dermatologist regarding product efficacy (skin tone, antiwrinkle, pigmentation), and (iii) volunteers self-evaluation. The L* value of spectrophotometer reading represents lightness in the skin pigment. Reduction in the pigment was reported from day 14, with significant reductions observed till day 84 compared with baseline. Significant (P < .0001) skin pigmentation lightening was seen on day 14 (1.11) vastly improving on day 84 (1.94) based on photographic assessments. The significant reduction in skin pigment was 76.85%, Felix von Luschan skin color score was 30.24% (P < .0001) with a 7.38-fold reduction in skin tone and 57% reduction in facial wrinkles at day 84 from baseline. Rosa E pigmentation serum was found safe and effective in significant reduction in skin pigments, improvement of skin tone, and antiwrinkle properties instrumentally, clinically, and self-evaluation by volunteers. In these evaluations, best results were seen the longer the Rosa E was used. © 2017 Wiley Periodicals, Inc.

  4. Barrier Requirements as the Evolutionary “Driver” of Epidermal Pigmentation in Humans

    PubMed Central

    ELIAS, PETER M.; MENON, GOPINATHAN; WETZEL, BRUCE K.; WILLIAMS, JOHN (JACK) W.

    2011-01-01

    Current explanations for the development of epidermal pigmentation during human evolution are not tenable as stand-alone hypotheses. Accordingly, we assessed instead whether xeric- and UV-B-induced stress to the epidermal permeability barrier, critical to survival in a terrestrial environment, could have “driven” the development of epidermal pigmentation. (1) Megadroughts prevailed in central Africa when hominids expanded into open savannahs [≈1.5–0.8 million years ago], resulting in sustained exposure to both extreme aridity and erythemogenic UV-B, correlating with genetic evidence that pigment developed ≈1.2 million years ago. (2) Pigmented skin is endowed with enhanced permeability barrier function, stratum corneum integrity/cohesion, and a reduced susceptibility to infections. The enhanced function of pigmented skin can be attributed to the lower pH of the outer epidermis, likely due to the persistence of (more-acidic) melanosomes into the outer epidermis, as well as the conservation of genes associated with eumelanin synthesis and melanosome acidification (e.g., TYR, OCA2 [p protein], SLC24A5, SLC45A2, MATP) in pigmented populations. Five keratinocyte-derived signals (stem cell factor⇒KIT; FOXn1⇒FGF2; IL-1α, NGF, and p53) are potential candidates to have stimulated the sequential development of epidermal pigmentation in response to stress to the barrier. We summarize evidence here that epidermal interfollicular pigmentation in early hominids likely evolved in response to stress to the permeability barrier. PMID:20209486

  5. The protease-activated receptor 2 regulates pigmentation via keratinocyte-melanocyte interactions.

    PubMed

    Seiberg, M; Paine, C; Sharlow, E; Andrade-Gordon, P; Costanzo, M; Eisinger, M; Shapiro, S S

    2000-01-10

    Close association exists between melanocytes, the pigment melanin-producing cells in the body, and their neighboring keratinocytes. Keratinocytes are the pigment recipients and skin pigmentation is the result of this interaction. While the chemical basis of melanin production (melanogenesis) is well documented, the molecular mechanism of melanosome transfer needs to be elucidated. We are now providing first evidence that the protease-activated receptor 2 (PAR-2) expressed on keratinocytes, but not on melanocytes, is involved in melanosome transfer and therefore may regulate pigmentation. Activation of PAR-2 with trypsin or with the peptide agonist SLIGRL induced pigmentation in both two- and three-dimensional cocultures of keratinocytes and melanocytes, but not in cocultures that were spatially separated, indicating the need for intimate cell-cell contact. Topical application of SLIGRL on human skin transplanted on SCID mice resulted in a visible skin darkening. Histological examination revealed increased deposits of melanin in the keratinocytes. Inhibition of PAR-2 activation by RWJ-50353, a serine protease inhibitor, resulted in depigmentation and changes in expression of melanogenic-specific genes. Keratinocyte-melanocyte contact was essential for this depigmenting effect. Topical application of this inhibitor induced lightening of the dark skin Yucatan swine, which was confirmed by histochemical analysis. The results presented here suggest a novel mechanism for the regulation of pigmentation, mediated by the activation or inhibition of the keratinocyte receptor PAR-2. Copyright 2000 Academic Press.

  6. Image analysis of skin color heterogeneity focusing on skin chromophores and the age-related changes in facial skin.

    PubMed

    Kikuchi, Kumiko; Masuda, Yuji; Yamashita, Toyonobu; Kawai, Eriko; Hirao, Tetsuji

    2015-05-01

    Heterogeneity with respect to skin color tone is one of the key factors in visual perception of facial attractiveness and age. However, there have been few studies on quantitative analyses of the color heterogeneity of facial skin. The purpose of this study was to develop image evaluation methods for skin color heterogeneity focusing on skin chromophores and then characterize ethnic differences and age-related changes. A facial imaging system equipped with an illumination unit and a high-resolution digital camera was used to develop image evaluation methods for skin color heterogeneity. First, melanin and/or hemoglobin images were obtained using pigment-specific image-processing techniques, which involved conversion from Commission Internationale de l'Eclairage XYZ color values to melanin and/or hemoglobin indexes as measures of their contents. Second, a spatial frequency analysis with threshold settings was applied to the individual images. Cheek skin images of 194 healthy Asian and Caucasian female subjects were acquired using the imaging system. Applying this methodology, the skin color heterogeneity of Asian and Caucasian faces was characterized. The proposed pigment-specific image-processing techniques allowed visual discrimination of skin redness from skin pigmentation. In the heterogeneity analyses of cheek skin color, age-related changes in melanin were clearly detected in Asian and Caucasian skin. Furthermore, it was found that the heterogeneity indexes of hemoglobin were significantly higher in Caucasian skin than in Asian skin. We have developed evaluation methods for skin color heterogeneity by image analyses based on the major chromophores, melanin and hemoglobin, with special reference to their size. This methodology focusing on skin color heterogeneity should be useful for better understanding of aging and ethnic differences. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. 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

  8. 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.

  9. 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

  10. 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.

  11. New insights into melanosome transport in vertebrate pigment cells.

    PubMed

    Aspengren, Sara; Hedberg, Daniel; Sköld, Helen Nilsson; Wallin, Margareta

    2009-01-01

    Pigment cells of lower vertebrates provide an excellent model to study organelle transport as they specialize in the translocation of pigment granules in response to defined chemical cues. This review will focus on the well-studied melanophore/melanocyte systems in fish, amphibians, and mammals. We will describe the roles of melanin, melanophores, and melanocytes in animals, current views on how the three motor proteins dynein, kinesin, and myosin-V are involved in melanosome transport along microtubules and actin filaments, and how signal transduction pathways regulate the activities of the motors to achieve aggregation and dispersion of melanosomes. We will also describe how melanosomes are transferred to surrounding skin cells in amphibians and mammals. Comparative studies have revealed that the ability of physiological color change is lost during evolution while the importance of morphological color change, mainly via transfer of pigment to surrounding skin cells, increases. In humans, pigment mainly has a role in protection against ultraviolet radiation, but also perhaps in the immune system.

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

    PubMed Central

    2014-01-01

    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. PMID:24661309

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

    PubMed Central

    Hawes, Norman L.; Trantow, Colleen M.; Chang, Bo; John, Simon W.M.

    2010-01-01

    Summary 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 sixteen 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. PMID:18715234

  14. 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.

  15. Skin graft

    MedlinePlus

    ... that need skin grafts to heal Venous ulcers, pressure ulcers , or diabetic ulcers that do not heal Very ... graft; Full thickness skin graft Patient Instructions Preventing pressure ulcers Surgical wound care - open Images Skin graft Skin ...

  16. [Sepsis caused by pigmented and no pigmented Chromobacterium violaceum].

    PubMed

    Guevara, Armando; Salomón, Marlly; Oliveros, María; Guevara, Esmirna; Guevara, Milarys; Medina, Laida

    2007-10-01

    Chromobacterium violaceum sepsis is rare but associated with a high mortality rate. We report a fatal case of C. violaceum sepsis in a 6 years old Venezuelan indian boy. Clinical manifestations were fever and swelling in the right inguinal region. The initial diagnosis was an appendicular plastron. Appendicectomy was performed and during surgery a right psoas abscess was identified that resulted culture positive for pigmented C. violaceum. Blood cultures were positive for a pigmented and non pigmented C. violaceum strain. Imipenem and amikacin were administered despite of which the child died 9 days after hospital admission.

  17. 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

  18. Skin autofluorescence reflects individual seasonal UV exposure, skin photodamage and skin cancer development in organ transplant recipients.

    PubMed

    Togsverd-Bo, Katrine; Philipsen, Peter Alshede; Hædersdal, Merete; Wulf, Hans Christian Olsen

    2018-01-01

    Ultraviolet radiation (UVR)-induced skin cancers varies among organ transplant recipients (OTRs). To improve individual risk assessment of skin cancer, objectively quantified skin photodamage is needed. We measured personal UVR-exposure dose in OTRs and assessed the relation between individual UVR exposure, skin cancer and objectively measured photodamage in terms of skin autofluorescence, pigmentation, and black light-evaluated solar lentigines. Danish OTRs with (n=15) and without a history of skin cancer (n=15) kept sun diaries from May to September and wore personal dosimeters recording time-stamped UVR doses in standard erythema doses (SED). Photodamage was quantified as skin autofluorescence with excitation at 370nm (F370) and 430nm (F430), skin pigmentation (pigment protection factor, PPF), and black light-evaluated solar lentigines. OTRs with skin cancer received a higher UVR dose than OTRs without skin cancer (median 116 SED vs. 67 SED, p=0.07) and UVR exposure doses were correlated with increased PPF (p=0.052) and F370 on the shoulder (F370 shoulder ) (p=0.04). We found that skin cancer was associated with F370 shoulder (OR 10.53, CI 3.3-31,938; p=0.018) and time since transplantation (OR 1.34, CI 0.95-1.91, p=0.097). A cut-off at 7.2 arbitrary units, 89% of OTRs with skin cancer had F370 shoulder values above 7.2 arbitrary units and F370 shoulder was additionally related to patient age (p=0.09) and black light-evaluated solar lentigines (p=0.04). F370 autofluorescence indicates objectively measured photodamage and may be used for individual risk assessment of skin cancer development in OTRs. Copyright © 2017. Published by Elsevier B.V.

  19. The red-green visual pigment gene region in adrenoleukodystrophy.

    PubMed Central

    Aubourg, P; Feil, R; Guidoux, S; Kaplan, J C; Moser, H; Kahn, A; Mandel, J L

    1990-01-01

    Although recent data established that a specific very-long-chain fatty acyl-CoA synthetase is defective in X-linked adrenoleukodystrophy (ALD), the ALD gene is still unidentified. The ALD locus has been mapped to Xq28, like the red and green color pigment genes. Abnormal color vision has been observed in 12 of 27 patients with adrenomyeloneuropathy (AMN), a milder form of ALD. Furthermore, rearrangements of the color vision gene cluster were found in four of eight ALD kindreds. This led us to propose that a single DNA rearrangement could underlie both ALD and abnormal color vision in these patients. Study of 34 French ALD patients failed to reveal a higher than expected frequency of green/red visual pigment rearrangements 3' to the red/green color vision gene complex. The previous report of such rearrangements was based on small numbers and lack of knowledge that the frequency of "abnormal" color vision arrays on molecular analysis was twice as high as expected on the basis of the frequency of phenotypic color vision defects. The red/green color pigment (R/GCP) region was studied by pulsed-field gel electrophoresis in 14 of these patients, and we did not find any fragment size difference between the patients and normal individuals who have the same number of pigment genes. The R/GCP region was also analyzed in 29 French and seven North American ALD patients by using six genomic DNA probes, isolated from a cosmid walk, that flank the color vision genes. No deletions were found with probes that lie 3' of the green pigment genes. One of the eight previously reported ALD individuals has a long deletion 5' of the red pigment gene, a deletion causing blue cone monochromacy. This finding and the previous findings of a 45% frequency of phenotypic color vision defects in patients with AMN may suggest that the ALD/AMN gene lies 5' to the red pigment gene and that the frequent phenotypic color vision anomalies owe their origin to deleted DNA that includes regulatory genes for

  20. 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

  1. Using Dermoscopic Criteria and Patient-Related Factors for the Management of Pigmented Melanocytic Nevi

    PubMed Central

    Zalaudek, Iris; Docimo, Giovanni; Argenziano, Giuseppe

    2010-01-01

    Objective: To review recent dermoscopy studies that provide new insights into the evolution of nevi and their patterns of pigmentation as they contribute to the diagnosis of nevi and the management of pigmented melanocytic nevi. Data Sources: Data for this article were identified by searching the English and German literature by Medline and Journals@Ovid search for the period 1950 to January 2009. Study Selection: The following relevant terms were used: dermoscopy, dermatoscopy, epiluminescence microscopy (ELM), surface microscopy, digital dermoscopy, digital dermatoscopy, digital epiluminescence microscopy, digital surface microscopy, melanocytic skin lesion, nevi, and pigmented skin lesions. There were no exclusion criteria. Data Synthesis: The dermoscopic diagnosis of nevi relies on the following 4 criteria (each of which is characterized by 4 variables): (1) color (black, brown, gray, and blue); (2) pattern (globular, reticular, starburst, and homogeneous blue pattern); (3) pigment distribution (multifocal, central, eccentric, and uniform); and (4) special sites (face, acral areas, nail, and mucosa). In addition, the following 6 factors related to the patient might influence the pattern of pigmentation of the individual nevi: age, skin type, history of melanoma, UV exposure, pregnancy, and growth dynamics. Conclusions: The 4×4×6 “rule” may help clinicians remember the basic dermoscopic criteria of nevi and the patient-related factors influencing their patterns. Dermoscopy is a useful technique for diagnosing melanocytic nevi, but the clinician should take additional factors into consideration to optimize the management of cases of pigmented lesions. PMID:19620566

  2. Towards noncontact skin melanoma selection by multispectral imaging analysis.

    PubMed

    Kuzmina, Ilona; Diebele, Ilze; Jakovels, Dainis; Spigulis, Janis; Valeine, Lauma; Kapostinsh, Janis; Berzina, Anna

    2011-06-01

    A clinical trial comprising 334 pigmented and vascular lesions has been performed in three Riga clinics by means of multispectral imaging analysis. The imaging system Nuance 2.4 (CRi) and self-developed software for mapping of the main skin chromophores were used. Specific features were observed and analyzed for malignant skin melanomas: notably higher absorbance (especially as the difference of optical density relative to the healthy skin), uneven chromophore distribution over the lesion area, and the possibility to select the "melanoma areas" in the correlation graphs of chromophores. The obtained results indicate clinical potential of this technology for noncontact selection of melanoma from other pigmented and vascular skin lesions.

  3. 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.

  4. 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

  5. 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.

  6. Abnormal Uterine Bleeding FAQ

    MedlinePlus

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

  7. Abnormal Uterine Bleeding

    MedlinePlus

    ... abnormal uterine bleeding? Abnormal uterine bleeding is any heavy or unusual bleeding from the uterus (through your ... one symptom of abnormal uterine bleeding. Having extremely heavy bleeding during your period can also be considered ...

  8. 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

  9. Computerized pigment design based on property hypersurfaces

    NASA Astrophysics Data System (ADS)

    Halova, Jaroslava; Sulcova, Petra; Kupka, Karel

    2007-05-01

    Competition is tough in the pigment market. Rational pigment design has therefore a competitive advantage, saving time and money. The aim of this work is to provide methods that can assist in designing pigments with defined properties. These methods include partial least squares regression (PLSR), neural network (NN) and generalized regression ANOVA model. Authors show how PLS bi-plot can be used to identify market gaps poorly covered by pigment manufacturers, thus giving an opportunity to develop pigments with potentially profitable properties.

  10. On the orientation of stripes in fish skin patterning.

    PubMed

    Míguez, David G; Muñuzuri, Alberto P

    2006-11-20

    This paper is focused on the study of the stripes orientation in the fish skin patterns. Based on microscopic observations of the pigment cells behavior at the embryonic stage, the key aspects of the pigmentation process are implemented in an experimental reaction-diffusion system. The experiment consists of a photosensitive Turing pattern of stripes growing directionally in one direction with controlled velocity. Different growth velocities of the system rearrange the stripes in the same three possible orientations observed in the skin of the colored fishes: parallel, oblique, and perpendicular. Our results suggest that the spreading velocity of the pigment cells in the fish dermis selects the orientation in the patterning processes.

  11. Ultrastructural analysis of the pigment dispersion syndrome in DBA/2J mice.

    PubMed

    Schraermeyer, Mareike; Schnichels, Sven; Julien, Sylvie; Heiduschka, Peter; Bartz-Schmidt, Karl-Ulrich; Schraermeyer, Ulrich

    2009-11-01

    To characterise ocular pigment abnormalities associated with iris atrophy in DBA/2J mice as a model for human pigment dispersion syndrome. Immunohistochemistry, electron and light microscopy were performed to examine the eyes of DBA/2J mice ranging in age from 2.5 to 18 months old. The focus of our study was the description of the ultrastructural modifications in the irides of DBA/2J mice. The DBA/2J mice presented modifications in the melanosomes in all the pigmented parts of the eye, including the retinal pigment epithelial cells and choroidal melanocytes of the ciliary pigment epithelium. The extracellular matrix of the iris stroma disappeared with ageing. Pigmented cells detached from the iris and migrated into the trabecular meshwork exclusively on the anterior iris surface. These cells were identified as macrophages by immunohistochemistry and electron microscopy. There was no evidence that melanocytes or iris pigment epithelial cells migrated into the trabecular meshwork, but they became more and more depigmented. The aqueous outflow was blocked by pigment-laden cells, but not by cellular debris or melanosomes. No substantial amount of extracellular melanosomes was observed. The morphology of melanosomes is aberrant in all pigment cells in the eyes of DBA/2J mice. We conclude that the disease process begins with the transfer of both immature melanosomes from the iris pigment epithelium (IPE) and melanocytes to macrophages, which subsequently migrate into the trabecular meshwork. Accumulating macrophages cause a blockade of the chamber angle. As the disease progresses, the IPE, melanocytes and iris stroma, including blood vessels, disappear, leading to iris atrophy. It is speculated that the loss of these pigment cells is partly caused by reduction of the iris stroma.

  12. Recognition of skin cancer and sun protective behaviors in skin of color.

    PubMed

    Wheat, Chikoti M; Wesley, Naissan O; Jackson, Brooke A

    2013-09-01

    Sun protective behaviors are not as frequently practiced in skin of color as they are amongst Caucasians.1 Thus providing a reasonable assumption this behavior, or lack thereof, increases the risk of skin cancer in this skin of color populations. The aim of this study was two-fold-- the first was to understand whether patients with skin of color, when categorized by ethnicity or skin type, are able to recognize skin cancer lesions. The second was to examine the correlation between ethnicity and/or skin type and practice of sun protective behaviors. We surveyed 105 respondents presenting for various skin problems in a dermatology office in Chicago, IL. Topics covered in the survey included recognition of skin cancer appearance and choice of sun protective behaviors. We show that there is a tendency for patients to potentially recognize atypical pigmented lesions when they are "dark moles with irregular borders" or "new moles". In contrast, there is a reduced ability among darkly pigmented skin types IV to VI, to recognize non-melanoma skin cancers. We also show that in addition to ethnicity, skin type within ethnic groups may also play an influential role on the decision to protect or not protect oneself from the sun.

  13. Retinal abnormalities in β-thalassemia major.

    PubMed

    Bhoiwala, Devang L; Dunaief, Joshua L

    2016-01-01

    Patients with beta (β)-thalassemia (β-TM: β-thalassemia major, β-TI: β-thalassemia intermedia) have a variety of complications that may affect all organs, including the eye. Ocular abnormalities include retinal pigment epithelial degeneration, angioid streaks, venous tortuosity, night blindness, visual field defects, decreased visual acuity, color vision abnormalities, and acute visual loss. Patients with β-thalassemia major are transfusion dependent and require iron chelation therapy to survive. Retinal degeneration may result from either retinal iron accumulation from transfusion-induced iron overload or retinal toxicity induced by iron chelation therapy. Some who were never treated with iron chelation therapy exhibited retinopathy, and others receiving iron chelation therapy had chelator-induced retinopathy. We will focus on retinal abnormalities present in individuals with β-thalassemia major viewed in light of new findings on the mechanisms and manifestations of retinal iron toxicity. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. 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

  15. The impact of skin colour on human photobiological responses.

    PubMed

    Fajuyigbe, Damilola; Young, Antony R

    2016-11-01

    Terrestrial solar ultraviolet radiation (UVR) exerts both beneficial and adverse effects on human skin. Epidemiological studies show a lower incidence of skin cancer in people with pigmented skins compared to fair skins. This is attributed to photoprotection by epidermal melanin, as is the poorer vitamin D status of those with darker skins. We summarize a wide range of photobiological responses across different skin colours including DNA damage and immunosuppression. Some studies show the generally modest photoprotective properties of melanin, but others show little or no effect. DNA photodamage initiates non-melanoma skin cancer and is reduced by a factor of about 3 in pigmented skin compared with white skin. This suggests that if such a modest reduction in DNA damage can result in the significantly lower skin cancer incidence in black skin, the use of sunscreen protection might be extremely beneficial for susceptible population. Many contradictory results may be explained by protocol differences, including differences in UVR spectra and exposure protocols. We recommend that skin type comparisons be done with solar-simulated radiation and standard erythema doses or physical doses (J/m 2 ) rather than those based solely on clinical endpoints such as minimal erythema dose (MED). © 2016 The Authors. Pigment Cell & Melanoma Research Published by John Wiley & Sons Ltd.

  16. Correlations Between Macular, Skin, and Serum Carotenoids

    PubMed Central

    Conrady, Christopher D.; Bell, James P.; Besch, Brian M.; Gorusupudi, Aruna; Farnsworth, Kelliann; Ermakov, Igor; Sharifzadeh, Mohsen; Ermakova, Maia; Gellermann, Werner; Bernstein, Paul S.

    2017-01-01

    Purpose Ocular and systemic measurement and imaging of the macular carotenoids lutein and zeaxanthin have been employed extensively as potential biomarkers of AMD risk. In this study, we systematically compare dual wavelength retinal autofluorescence imaging (AFI) of macular pigment with skin resonance Raman spectroscopy (RRS) and serum carotenoid levels in a clinic-based population. Methods Eighty-eight patients were recruited from retina and general ophthalmology practices from a tertiary referral center and excluded only if they did not have all three modalities tested, had a diagnosis of macular telangiectasia (MacTel) or Stargardt disease, or had poor AFI image quality. Skin, macular, and serum carotenoid levels were measured by RRS, AFI, and HPLC, respectively. Results Skin RRS measurements and serum zeaxanthin concentrations correlated most strongly with AFI macular pigment volume under the curve (MPVUC) measurements up to 9° eccentricity relative to MPVUC or rotationally averaged macular pigment optical density (MPOD) measurements at smaller eccentricities. These measurements were reproducible and not significantly affected by cataracts. We also found that these techniques could readily identify subjects taking oral carotenoid-containing supplements. Conclusions Larger macular pigment volume AFI and skin RRS measurements are noninvasive, objective, and reliable methods to assess ocular and systemic carotenoid levels. They are an attractive alternative to psychophysical and optical methods that measure MPOD at a limited number of eccentricities. Consequently, skin RRS and MPVUC at 9° are both reasonable biomarkers of macular carotenoid status that could be readily adapted to research and clinical settings. PMID:28728169

  17. Reflectance spectroscopy of pigmented cutaneous benign and malignant lesions

    NASA Astrophysics Data System (ADS)

    Borisova, E.; Jeliazkova, Al.; Pavlova, E.; Troyanova, P.; Kundurdjiev, T.; Pavlova, P.; Avramov, L.

    2014-10-01

    For the DRS measurements of skin benign, dysplastic and malignant lesions in vivo we applied halogen lamp (LS-1, OceanOptics Inc, Dunedin, Fl, USA) as a continuous light source in the region of 400-900 nm, optical probe (6+1 fibers) for the delivery of illumination and diffuse reflected light from the skin investigated and microspectrometer USB4000 (OceanOptics Inc., Dunedin, Fl, USA) for a storage and display of the spectra detected. As a diffuse reflectance standard Spectralon® plate was used to calibrate the spectrometer. The reflectance spectra obtained from normal skin in identical anatomic sites of different patients have similar spectral shape features, slightly differ by the reflectance intensity at different wavelengths, depending on the particular patient' skin phototype. One could find diagnostically important spectral features, related to specific intensity changes for a given wavelength due to specific pigments appearance, slope changes by value and sign for the reflectance spectra curves in a specific spectral range, disappearance or manifestation of minima, related to hemoglobin absorption at 410-420 nm, 543, 575 nm. Based on the observed peculiarities multispectral analysis of the reflectance spectra of the different lesions was used and diagnostically specific features are found. Discrimination using the DRS data obtained between benign compound and dermal nevi (45 cases), dysplastic nevi (17 cases) and pigmented malignant melanoma (41 cases) lesions is achieved with a diagnostic accuracy of 96 % for the benign nevi vs. MM, and 90 % for the dysplastic nevi vs. MM.

  18. Modeling of Light Reflection from Human Skin

    NASA Astrophysics Data System (ADS)

    Delgado, J. A.; Cornejo, A.; Rivas-Silva, J. F.; Rodríguez, E. E.

    2006-09-01

    In this work a two-layer model is used to simulate the spectral reflectance of adult human skin. We report and discuss diffuse reflectance spectra of this model for three values of the volume fraction of melanosomes fme, namely a) lightly pigmented skin fme = 4%, b) moderately pigmented skin fme = 14% and c) heavily pigmented skin fme = 30% at a volume fraction of blood fbl = 0.2%. We also considered the modeling of reflectance spectra for two values of fbl (0.2% and 1%) with fme = 4%. Both simulations were done in the 400-700 nm spectral range using the Monte Carlo simulation code MCML in standard C. Results showed that the principal signatures of human skin reflectance spectrum are obtained with this model and that it could be of valuable use to made predictions of diffuse reflectance of human skin for different values of the parameters related to skin characterization. These parameters can be associated to distinct medical conditions, such as erythema, jaundice, etc.

  19. Teledermatology Applications in Skin Cancer Diagnosis.

    PubMed

    Walocko, Frances M; Tejasvi, Trilokraj

    2017-10-01

    Teledermatology has drawn interest in the dermatologic community, because it allows for earlier detection of skin cancer in patients with poor access to health care. Using a combination of dermoscopy and digital photography, teledermatology has demonstrated acceptable concordance with face-to-face clinical diagnoses in multiple settings for pigmented skin lesions. Additional studies on using teledermatology to assess nonpigmented skin lesions are needed. Future advances in mobile teledermatology may help make this technology more widespread and affordable. Although teledermatology is not a replacement for regular total body skin examinations, it is a useful tool to significantly reduce the burden of dermatologic malignancies. Published by Elsevier Inc.

  20. 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.

  1. 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.

  2. 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, ...

  3. Are dark-skinned people really protected from ultraviolet radiation?

    PubMed

    Young, A L; Levy, S; Nighland, M; Grossman, R; Silvers, D N; Celebi, J T

    2010-06-01

    Premature ageing of the skin (photoageing) results from the action of ultraviolet radiation (UVR) on skin. One of the histopathological findings of photoageing is the presence of solar elastosis in the dermis. Skin pigmentation is protective against UVR. To evaluate the presence of solar elastosis in dark-skinned people. Normal facial skin biopsies of 147 dark-skinned and 140 light-skinned people were examined histopathologically for solar elastosis. The degree of solar elastosis was graded on a five-point scale by a panel of dermatopathologists blinded to patient demographics. There were 112 of 140 (80%) light-skinned and 50 of 147 (34%) dark-skinned patients with high-grade solar elastosis. In the dark-skinned patient group, high-grade solar elastosis was seen in 29 of 61 (47.5%) Hispanic and 5 of 49 (10.2%) African American subjects. Dark-skinned people are not completely protected from the effects of UVR.

  4. Removal of dogs' gingival pigmentation with CO2 laser

    NASA Astrophysics Data System (ADS)

    Figueiredo, Jose A. P.; Chavantes, Maria C.; Gioso, Marco A.; Pesce, Hildeberto F.; Jatene, Adib D.

    1995-05-01

    The aim of this study was to analyze the ability of CO2 laser to remove physiologic pigmentation of gingiva. Dogs were chosen for this study because of their intense black pigmentation on the gingiva, similar to what can be found in human negroes and other dark- skinned races. Three specimens were irradiated at the left side of the buccal aspect of the gingiva, while for comparison the right side was used as a control. CO2 laser in a continuous mode applying 3 watt power was used (Xanar-20, USA). The portion to be irradiated was continuously irrigated with saline solution, to prevent tissue damage from the excessive heat generated. The handpiece device irradiated the target easily and fast, with no bleeding. All the pigmentation could be removed from the portion exposed to the laser beam. A 45th day follow up showed very little repigmentation just in one of the specimens. It could be concluded that CO2 laser irradiation can be an alternative to remove pigmentation of the gingiva for cosmetic purposes. The risk of repigmentation exists, so the patients should be aware of this inconvenience, sometimes demanding further irradiation.

  5. Cryotherapy - skin

    MedlinePlus

    ... skin; Warts - freezing; Warts - cryotherapy; Actinic keratosis - cryotherapy; Solar keratosis - cryotherapy ... warts Destroy precancerous skin lesions (actinic keratoses or solar keratoses) In rare cases, cryotherapy is used to ...

  6. 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 ...

  7. Annular and central heavy pigment deposition on the posterior lens capsule in the pigment dispersion syndrome: pigment deposition on the posterior lens capsule in the pigment dispersion syndrome.

    PubMed

    Turgut, Burak; Türkçüoğlu, Peykan; Deniz, Nurettin; Catak, Onur

    2008-12-01

    To report annular and central heavy pigment deposition on the posterior lens capsule in a case of pigment dispersion syndrome. Case report. A 36-year-old female with bilateral pigment dispersion syndrome presented with progressive decrease in visual acuity in the right eye over the past 1-2 years. Clinical examination revealed the typical findings of pigment dispersion syndrome including bilateral Krunkenberg spindles, iris transillumination defects, and dense trabecular meshwork pigmentation. Remarkably, annular and central dense pigmentation of the posterior lens capsule was noted in the right eye. Annular pigment deposition on the posterior lens capsule may be a rare finding associated with pigment dispersion syndrome. Such a finding suggests that there may be aqueous flow into the retrolental space in some patients with this condition. The way of central pigmentation is the entrance of aqueous to Berger's space. In our case, it is probable that spontaneous detachment of the anterior hyaloid membrane aided this entrance.

  8. 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.

  9. 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.

  10. The expression and activation of protease-activated receptor-2 correlate with skin color.

    PubMed

    Babiarz-Magee, Laura; Chen, Nannan; Seiberg, Miri; Lin, Connie B

    2004-06-01

    Skin color results from the production and distribution of melanin in the epidermis. The protease-activated receptor-2 (PAR-2), expressed on keratinocytes but not on melanocytes, is involved in melanosome uptake via phagocytosis, and modulation of PAR-2 activation affects skin color. The pattern of melanosome distribution within the epidermis is skin color-dependent. In vitro, this distribution pattern is regulated by the ethnic origin of the keratinocytes, not the melanocytes. Therefore, we hypothesized that PAR-2 may play a role in the modulation of pigmentation in a skin type-dependent manner. We examined the expression of PAR-2 and its activator, trypsin, in human skins with different pigmentary levels. Here we show that PAR-2 and trypsin are expressed in higher levels, and are differentially localized in highly pigmented, relative to lightly pigmented skins. Moreover, highly pigmented skins exhibit an increase in PAR-2-specific protease cleavage ability. Microsphere phagocytosis was more efficient in keratinocytes from highly pigmented skins, and PAR-2 induced phagocytosis resulted in more efficient microsphere ingestion and more compacted microsphere organization in dark skin-derived keratinocytes. These results demonstrate that PAR-2 expression and activity correlate with skin color, suggesting the involvement of PAR-2 in ethnic skin color phenotypes.

  11. Melanoma: Genetic Abnormalities, Tumor Progression, Clonal Evolution and Tumor Initiating Cells.

    PubMed

    Testa, Ugo; Castelli, Germana; Pelosi, Elvira

    2017-11-20

    Melanoma is an aggressive neoplasia issued from the malignant transformation of melanocytes, the pigment-generating cells of the skin. It is responsible for about 75% of deaths due to skin cancers. Melanoma is a phenotypically and molecularly heterogeneous disease: cutaneous, uveal, acral, and mucosal melanomas have different clinical courses, are associated with different mutational profiles, and possess distinct risk factors. The discovery of the molecular abnormalities underlying melanomas has led to the promising improvement of therapy, and further progress is expected in the near future. The study of melanoma precursor lesions has led to the suggestion that the pathway of tumor evolution implies the progression from benign naevi, to dysplastic naevi, to melanoma in situ and then to invasive and metastatic melanoma. The gene alterations characterizing melanomas tend to accumulate in these precursor lesions in a sequential order. Studies carried out in recent years have, in part, elucidated the great tumorigenic potential of melanoma tumor cells. These findings have led to speculation that the cancer stem cell model cannot be applied to melanoma because, in this malignancy, tumor cells possess an intrinsic plasticity, conferring the capacity to initiate and maintain the neoplastic process to phenotypically different tumor cells.

  12. Melanoma: Genetic Abnormalities, Tumor Progression, Clonal Evolution and Tumor Initiating Cells

    PubMed Central

    Castelli, Germana; Pelosi, Elvira

    2017-01-01

    Melanoma is an aggressive neoplasia issued from the malignant transformation of melanocytes, the pigment-generating cells of the skin. It is responsible for about 75% of deaths due to skin cancers. Melanoma is a phenotypically and molecularly heterogeneous disease: cutaneous, uveal, acral, and mucosal melanomas have different clinical courses, are associated with different mutational profiles, and possess distinct risk factors. The discovery of the molecular abnormalities underlying melanomas has led to the promising improvement of therapy, and further progress is expected in the near future. The study of melanoma precursor lesions has led to the suggestion that the pathway of tumor evolution implies the progression from benign naevi, to dysplastic naevi, to melanoma in situ and then to invasive and metastatic melanoma. The gene alterations characterizing melanomas tend to accumulate in these precursor lesions in a sequential order. Studies carried out in recent years have, in part, elucidated the great tumorigenic potential of melanoma tumor cells. These findings have led to speculation that the cancer stem cell model cannot be applied to melanoma because, in this malignancy, tumor cells possess an intrinsic plasticity, conferring the capacity to initiate and maintain the neoplastic process to phenotypically different tumor cells. PMID:29156643

  13. Semi-automated non-invasive diagnostics method for melanoma differentiation from nevi and pigmented basal cell carcinomas

    NASA Astrophysics Data System (ADS)

    Lihacova, I.; Bolocko, K.; Lihachev, A.

    2017-12-01

    The incidence of skin cancer is still increasing mostly in in industrialized countries with light- skinned people. Late tumour detection is the main reason of the high mortality associated with skin cancer. The accessibility of early diagnostics of skin cancer in Latvia is limited by several factors, such as high cost of dermatology services, long queues on state funded oncologist examinations, as well as inaccessibility of oncologists in the countryside regions - this is an actual clinical problem. The new strategies and guidelines for skin cancer early detection and post-surgical follow-up intend to realize the full body examination (FBE) by primary care physicians (general practitioners, interns) in combination with classical dermoscopy. To implement this approach, a semi- automated method was established. Developed software analyses the combination of 3 optical density images at 540 nm, 650 nm, and 950 nm from pigmented skin malformations and classifies them into three groups- nevi, pigmented basal cell carcinoma or melanoma.

  14. CAPN3, DCT, MLANA and TYRP1 are overexpressed in skin of vitiligo vulgaris Mexican patients.

    PubMed

    Salinas-Santander, Mauricio; Trevino, Víctor; De la Rosa-Moreno, Eduardo; Verduzco-Garza, Bárbara; Sánchez-Domínguez, Celia N; Cantú-Salinas, Cristina; Ocampo-Garza, Jorge; Lagos-Rodríguez, Armando; Ocampo-Candiani, Jorge; Ortiz-López, Rocio

    2018-03-01

    Vitiligo is a disorder causing skin depigmentation, in which several factors have been proposed for its pathogenesis: Environmental, genetic and biological aspects of melanocytes, even those of the surrounding keratinocytes. However, the lack of understanding of the mechanisms has complicated the task of predicting the development and progression. The present study used microarray analysis to characterize the transcriptional profile of skin from Vitiligo Vulgaris (VV) patients and the identified transcripts were validated using targeted high-throughput RNA sequencing in a broader set of patients. For microarrays, mRNA was taken from 20 skin biopsies of 10 patients with VV (pigmented and depigmented skin biopsy of each), and 5 biopsies of healthy subjects matched for age and sex were used as a control. A signature was identified that contains the expression pattern of 722 genes between depigmented vitiligo skin vs. healthy control, 1,108 between the pigmented skin of vitiligo vs. healthy controls and 1,927 between pigmented skin, depigmented vitiligo and healthy controls (P<0.05; false discovery rate, <0.1). When comparing the pigmented and depigmented skin of patients with vitiligo, which reflects the real difference between both skin types, 5 differentially expressed genes were identified and further validated in 45 additional VV patients by RNA sequencing. This analysis showed significantly higher RNA levels of calpain-3, dopachrome tautomerase, melan-A and tyrosinase-related protein-1 genes. The data revealed that the pigmented skin of vitiligo is already affected at the level of gene expression and that the main differences between pigmented and non-pigmented skin are explained by the expression of genes associated with pigment metabolism.

  15. 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

  16. Human hair pigmentation--biological aspects.

    PubMed

    Tobin, D J

    2008-08-01

    Skin and hair colour contribute significantly to our overall visual appearance and to social/sexual communication. Despite their shared origins in the embryologic neural crest, the hair follicle and epidermal pigmentary units occupy distinct, although open, cutaneous compartments. They can be distinguished principally on the basis of the former's stringent coupling to the hair growth cycle compared with the latter's continuous melanogenesis. The biosynthesis of melanin and its subsequent transfer from melanocyte to hair bulb keratinocytes depend on the availability of melanin precursors and on a raft of signal transduction pathways that are both highly complex and commonly redundant. These signalling pathways can be both dependent and independent of receptors, act through auto-, para- or intracrine mechanisms and can be modified by hormonal signals. Despite many shared features, follicular melanocytes appear to be more sensitive than epidermal melanocytes to ageing influences. This can be seen most dramatically in hair greying/canities and this is likely to reflect significant differences in the epidermal and follicular microenvironments. The hair follicle pigmentary unit may also serve as an important environmental sensor, whereby hair pigment contributes to the rapid excretion of heavy metals, chemicals and toxins from the body by their selective binding to melanin; rendering the hair fibre a useful barometer of exposures. The recent availability of advanced cell culture methodologies for isolated hair follicle melanocytes and for intact anagen hair follicle organ culture should provide the research tools necessary to elucidate the regulatory mechanisms of hair follicle pigmentation. In the longer term, it may be feasible to develop hair colour modifiers of a biological nature to accompany those based on chemicals.

  17. Skin tightening.

    PubMed

    Woolery-Lloyd, Heather; Kammer, Jenna N

    2011-01-01

    Skin tightening describes the treatment of skin laxity via radiofrequency (RF), ultrasound, or light-based devices. Skin laxity on the face is manifested by progressive loss of skin elasticity, loosening of the connective tissue framework, and deepening of skin folds. This results in prominence of submandibular and submental tissues. Genetic factors (chronological aging) and extrinsic factors (ultraviolet radiation) both contribute to skin laxity. There are many RF, ultrasound, and light-based devices directed at treating skin laxity. All of these devices target and heat the dermis to induce collagen contraction. Heating of the dermis causes collagen denaturation and immediate collagen contraction in addition to long-term collagen remodeling. Via RF, light, or ultrasound, these skin tightening devices deliver heat to the dermis to create new collagen and induce skin tightening. This chapter will provide an overview of the various skin tightening devices. Copyright © 2011 S. Karger AG, Basel.

  18. 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 (V oc ) 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. © 2015 International Union of Biochemistry and Molecular Biology, Inc.

  19. Association between choroidal pigmentation and posterior uveal melanoma in a white population

    PubMed Central

    Harbour, J W; Brantley, M A; Hollingsworth, H; Gordon, M

    2004-01-01

    Background/aims: It is well known that light skin pigmentation is a risk factor for cutaneous melanoma. The aim of this study was to investigate the analogous association between choroidal pigmentation and posterior uveal melanoma. Methods: Cross sectional study of 65 consecutive patients diagnosed with posterior uveal melanoma (melanoma group) and 218 consecutive patients referred for general retinal evaluation (control group). All patients were white. A clinical grading system for estimating choroidal pigmentation was developed and histologically validated in seven patients. Results: Melanoma patients with light iris colour were significantly more likely to have darker choroidal pigmentation than controls (p = 0.005). Darker choroidal pigmentation was associated histologically with increased density of choroidal melanocytes (p = 0.005). Conclusions: Increased choroidal pigmentation, as a result of an increase in the density of pigmented choroidal melanocytes, is not protective but may actually be a risk factor for the development of posterior uveal melanoma in white patients. This finding may have implications for understanding the pathogenesis of uveal melanoma. PMID:14693770

  20. Pigmented lesions of the oral mucosa: A cross-sectional study of 458 histopathological specimens.

    PubMed

    Tavares, Thalita Soares; Meirelles, Daniela Pereira; de Aguiar, Maria Cássia Ferreira; Caldeira, Patrícia Carlos

    2018-06-26

    To evaluate clinical, demographic, and histopathological characteristics of pigmented lesions of the oral mucosa. A cross-sectional study was conducted over a 64-year period. Information was collected from medical charts, and all archived histopathologic specimens with diagnoses of any pigmented lesion were retrieved. Statistical analysis was performed using SPSS software. A total of 34,127 archived specimens were reviewed, revealing 458 (1.34%) pigmented lesions, of which 230 were melanocytic and 228 non-melanocytic. Most patients were females (74.2%), white-skinned (49.1%), in the third and seventh decades of life (mean of 45 years). Most lesions were macular (59.8%), followed by plaques and nodules (4.8%), measuring 0-5 mm (41.9%). Cheek mucosa (21.0%), alveolar mucosa (16.6%), and gingiva (11.8%) were the most commonly affected sites. Amalgam tattoo was applied in 212 cases (46.3%), followed by melanotic macule (22.9%) and nevus (20.5%). Other diagnoses included racial pigmentation, exogenous pigmentation, melanotic neuroectodermal tumor of infancy, melanoma, melanocanthoma, smoker's melanosis, and heavy metal pigmentation. Pigmented lesions represent an uncommon diagnosis in oral pathology routines. The most frequent entities are amalgam tattoo, melanotic macule, and nevus. Patients are usually middle-aged women presenting a small, long-lasting, macular lesion on the cheek mucosa. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  1. Towards the limiting of health risks associated with tattooing: whitelists for tattoo pigments and preservatives.

    PubMed

    Blume, Annegret; Platzek, Thomas; Vieth, Bärbel; Hutzler, Christoph; Luch, Andreas

    2015-01-01

    The number of pigments that could potentially be used in tattoo inks is vast. However, pigments are generally not manufactured for the purpose of being injected into subepidermal layers of the skin. Assuming 100% bioavailability after injection means that pigments can be imminently hazardous to human health. Given the ever-increasing number of pigments being circulated on the market or through the internet, a 'negative list' ('black' list) containing pigments with known adverse effects will never be finalised. If incriminated, substances could easily be replaced by structurally similar pigments that might be even more deleterious to human health. Therefore, we and others suggest the establishment of a whitelist ('positive list') that would only contain pigments that had undergone a risk assessment specifically for their application into the dermis. Some of the problems associated with such a 'positive list' are discussed. Another important issue with regard to tattoo safety is related to the preservatives used in ink preparations. Notwithstanding the demand for sterile tattoo inks, a whitelist for these compounds would be beneficial. At present, many technical preservatives are being used, despite their known detrimental effects to human health. Criteria for the inclusion of preservatives in a 'positive list' are also discussed. © 2015 S. Karger AG, Basel.

  2. Long anterior zonules and pigment dispersion.

    PubMed

    Moroi, Sayoko E; Lark, Kurt K; Sieving, Paul A; Nouri-Mahdavi, Kouros; Schlötzer-Schrehardt, Ursula; Katz, Gregory J; Ritch, Robert

    2003-12-01

    To describe pigment dispersion associated with long anterior zonules. Multicenter observational case series. Fifteen patients, seven of whom were treated for glaucoma or ocular hypertension, were identified with long anterior zonules and pigment dispersion. Transmission electron microscopy was performed on one anterior capsule specimen. All patients had anterior zonules that inserted centrally on the lens capsule. Signs of pigment dispersion included corneal endothelial pigmentation, loss of the pupillary ruff, and variable trabecular meshwork pigmentation. Ultrasound biomicroscopy verified the lack of posterior iris insertion and concavity. There was no exfoliation material. Transmission electron microscopy showed zonular lamellae with adherent pigment granules, and no exfoliation material. Long anterior zonules inserted onto the central lens capsule may cause mechanical disruption of the pigment epithelium at the pupillary ruff and central iris leading to pigment dispersion.

  3. Knock-Down of Cathepsin D Affects the Retinal Pigment Epithelium, Impairs Swim-Bladder Ontogenesis and Causes Premature Death in Zebrafish

    PubMed Central

    Follo, Carlo; Ozzano, Matteo; Mugoni, Vera; Castino, Roberta; Santoro, Massimo; Isidoro, Ciro

    2011-01-01

    The lysosomal aspartic protease Cathepsin D (CD) is ubiquitously expressed in eukaryotic organisms. CD activity is essential to accomplish the acid-dependent extensive or partial proteolysis of protein substrates within endosomal and lysosomal compartments therein delivered via endocytosis, phagocytosis or autophagocytosis. CD may also act at physiological pH on small-size substrates in the cytosol and in the extracellular milieu. Mouse and fruit fly CD knock-out models have highlighted the multi-pathophysiological roles of CD in tissue homeostasis and organ development. Here we report the first phenotypic description of the lack of CD expression during zebrafish (Danio rerio) development obtained by morpholino-mediated knock-down of CD mRNA. Since the un-fertilized eggs were shown to be supplied with maternal CD mRNA, only a morpholino targeting a sequence containing the starting ATG codon was effective. The main phenotypic alterations produced by CD knock-down in zebrafish were: 1. abnormal development of the eye and of retinal pigment epithelium; 2. absence of the swim-bladder; 3. skin hyper-pigmentation; 4. reduced growth and premature death. Rescue experiments confirmed the involvement of CD in the developmental processes leading to these phenotypic alterations. Our findings add to the list of CD functions in organ development and patho-physiology in vertebrates. PMID:21747967

  4. Pigment dispersion syndrome and pigmentary glaucoma: a review and update.

    PubMed

    Scuderi, Gianluca; Contestabile, Maria Teresa; Scuderi, Luca; Librando, Aloisa; Fenicia, Vito; Rahimi, Siavash

    2018-05-02

    Potential factors influencing stereopsis were investigated in patients with both refractive accommodative esotropia (RAE) and amblyopia. Pigment dispersion syndrome (PDS) is a condition where anomalous iridozonular contact leads to pigment dispersion throughout the anterior segment and the released pigment is abnormally deposited on various ocular structures. The clinical presentation of PDS is defined by the presence of pigmented cells on the corneal endothelium, an increase of pigmentation of the trabecular meshwork, and mid-periphery transillumination defects of the iris. This syndrome, more common in myopes, is usually bilateral and can be associated with ocular hypertension or glaucoma. Secondary open-angle pigmentary glaucoma (PG) can develop due to reduction of the outflow of aqueous humour and consequent increase in intraocular pressure leading to glaucomatous optic neuropathy. Diagnosis of PG is commonly between 40 and 50 years of age, occurring more frequently in men. The advent of ultrasound biomicroscopy and anterior segment optical coherence tomography has contributed to enhancing our knowledge on the condition. Typical alterations of the anterior segment are the posterior insertion of the iris and iris concavity. Treatment of PG should be initiated early to hinder disease progression, glaucomatous damage, and vision loss. Management is based on medical therapy, laser iridotomy, selective laser trabeculoplasty, and filtration procedures. The differential diagnosis of PDS with other disorders can be challenging and awareness of the condition together with meticulous ophthalmologic examination allows early diagnosis followed by appropriate management strategies. The present review is a comprehensive report on the clinical characteristics, pathogenesis, current management, and status quo of PDS and PG.

  5. Cis-regulatory changes in Kit ligand expression and parallel evolution of pigmentation in sticklebacks and humans

    PubMed Central

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

    2010-01-01

    SUMMARY 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. PMID:18083106

  6. 21 CFR 73.352 - Paracoccus pigment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... astaxanthin level. (2) Color additive mixtures for fish feed use made with paracoccus pigment may contain only...) Astaxanthin, not less than 1.75 percent. (c) Uses and restrictions. Paracoccus pigment may be safely used in... astaxanthin in finished feed, from paracoccus pigment when used alone or in combination with other astaxanthin...

  7. 21 CFR 73.352 - Paracoccus pigment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... astaxanthin level. (2) Color additive mixtures for fish feed use made with paracoccus pigment may contain only...) Astaxanthin, not less than 1.75 percent. (c) Uses and restrictions. Paracoccus pigment may be safely used in... astaxanthin in finished feed, from paracoccus pigment when used alone or in combination with other astaxanthin...

  8. 21 CFR 73.352 - Paracoccus pigment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... astaxanthin level. (2) Color additive mixtures for fish feed use made with paracoccus pigment may contain only...) Astaxanthin, not less than 1.75 percent. (c) Uses and restrictions. Paracoccus pigment may be safely used in... astaxanthin in finished feed, from paracoccus pigment when used alone or in combination with other astaxanthin...

  9. 21 CFR 73.352 - Paracoccus pigment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... astaxanthin level. (2) Color additive mixtures for fish feed use made with paracoccus pigment may contain only...) Astaxanthin, not less than 1.75 percent. (c) Uses and restrictions. Paracoccus pigment may be safely used in... astaxanthin in finished feed, from paracoccus pigment when used alone or in combination with other astaxanthin...

  10. 21 CFR 73.352 - Paracoccus pigment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... astaxanthin level. (2) Color additive mixtures for fish feed use made with paracoccus pigment may contain only...) Astaxanthin, not less than 1.75 percent. (c) Uses and restrictions. Paracoccus pigment may be safely used in... astaxanthin in finished feed, from paracoccus pigment when used alone or in combination with other astaxanthin...

  11. 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

  12. 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 ...

  13. 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.

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

    PubMed Central

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

    2012-01-01

    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. PMID:23130289

  15. Sagging Skin

    MedlinePlus

    ... for Varicose Veins Sclerotherapy for Varicose Veins Back Hair Transplants Laser Treatments for Pre-Cancerous ... Skin Sagging skin in the lower face and neck is a natural part of the aging process. Why treat sagging ...

  16. [Physiological skin changes during pregnancy].

    PubMed

    Schmutz, Jean-Luc

    2003-11-29

    A NATURAL PHENOMENON: Pregnancy is a period of hormone, immunological, metabolic and vascular changes. Modifications of the skin, mucosa and integuments are therefore physiological. The modifications are in pigmentation, but also affect nevi, the connective tissue, vessels and appendices. Modifications in pigmentation exist in more than 9 pregnancies out of 10 in the form of local melanosis. Melasma, also know as the 'pregnancy mask' or chloasma, is fairly rare. These disorders in pigmentation are also observed in black-skinned women. Changes in nevi (darker brown colour, increase in size) occur in around 15% of pregnancies. MODIFICATIONS IN CONNECTIVE TISSUE: Characterised by vergetures, affecting 60 to 90% of women, appear between the 6th and 8th month of pregnancy and for which there is no satisfactory treatment. Vascular modifications are generally proliferative and due to estrogen impregnation that affects the arteriolar and venous systems. Stellar angiomas are present in 50 to 70% of Caucasian women. Bilateral palmar erythema may also be associated with these angiomas. Varicose veins and varicosities of the lower limbs induced by excessive venous pressure are frequent, as well as oedema (salt-water retention, increased capillary permeability). MODIFICATIONS IN THE APPENDICES: These concern the activity of the sweat glands, the size of the sebaceous glands (Montgomery tubercles), the nails and hair growth.

  17. Analysis of yellowish skin color from an optical image and the development of 3D Skin Chroma Diagram(™).

    PubMed

    Han, J Y; Kim, E J; Lee, H K; Kim, M J; Nam, G W

    2015-08-01

    This study was conducted to define yellowish skin color, which is a major concern of Asian women, and to develop a 3D skin-pigment color model. A total of 22 Korean females were enrolled in this study. These women were asked to use a functional cosmetic product with whitening agents for 8 weeks. We photographed the subsurface reflection of each subject's face using polarized light. The color of the subsurface reflection is a result of diffusive light transports that are attenuated by various skin pigments such as melanin, hemoglobin, and skin base colors. In this subsurface photo image, we eliminated the color effects of melanin and hemoglobin distribution by skin color analysis resulting in skin base color. Based on a variety of observed skin base colors from which the melanin and hemoglobin pigments have been removed, we defined a standard skin color for the entire subject group, and then, we gained a particular yellowish skin color by excluding the standard skin color from the skin base color again. After applying whitening cosmetic products, the amount of melanin and hemoglobin was reduced by 7.3% and 18.6%, respectively. Also, through using our new analysis method, yellowish skin color has been improved by 2.8%. We showed the improvement on 3D Skin Chroma Diagram(™) three-dimensionally. It became possible to diagnose yellowish color on human skin and to analyze the improvement in skin tone both quantitatively and visually. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Ionic skin.

    PubMed

    Sun, Jeong-Yun; Keplinger, Christoph; Whitesides, George M; Suo, Zhigang

    2014-12-03

    Electronic skins (i.e., stretchable sheets of distributed sensors) report signals using electrons, whereas natural skins report signals using ions. Here, ionic conductors are used to create a new type of sensory sheet, called "ionic skin". Ionic skins are highly stretchable, transparent, and biocompatible. They readily measure strains from 1% to 500%, and pressures as low as 1 kPa. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. 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.

  20. Skin Biopsy

    MedlinePlus

    ... Staying Safe Videos for Educators Search English Español Skin Biopsy KidsHealth / For Teens / Skin Biopsy What's in ... en español Biopsia de piel What Is a Skin Biopsy and Who Would Need One? In a ...

  1. The Preventive Effect of Coffee Compounds on Dermatitis and Epidermal Pigmentation after Ultraviolet Irradiation in Mice.

    PubMed

    Yamate, Yurika; Hiramoto, Keiichi; Sato, Eisuke F

    2017-01-01

    Ultraviolet (UV) irradiation is well known to promote inflammation and pigmentation of skin. UVB mainly affects dermatitis and pigmentation. Coffee contains a number of polyphenols, such as caffeic acid (CA) and chlorogenic acid (CGA) but their in vivo bioactivity for photobiology remains unclear. C57BL/6j male mice were irradiated with UVB (1.0 kJ/m2/day) for 3 days. Five days after the final session of UVB irradiation, the dorsal skin, ear epidermis, and blood samples were analyzed to investigate the inflammatory factors, melanogenesis factors and related hormones. After the oral administration of CA (100 mg/day) or CGA (100 mg/day) for 8 days, only CA was found to inhibit dermatitis and pigmentation. The pathway by which CA inhibits dermatitis is related to the mitogen-activated protein kinase (MAPK)/extracellular signal regulated kinase (ERK)1/2/cAMP response element binding protein (CREB) pathway. Otherwise, the pathway by which CA inhibits pigmentation is related to the activation of the β-endorphin-μ-opioid receptor and suppresses the cAMP-microphthalmia-associated transcription factor (MITF) pathway. It is suggested that the oral administration of CA prevented dermatitis and pigmentation after UVB irradiation in mice. © 2017 S. Karger AG, Basel.

  2. 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. © 2010 John Wiley & Sons A/S.

  3. Interrelationships Between Maternal Carotenoid Status and Newborn Infant Macular Pigment Optical Density and Carotenoid Status

    PubMed Central

    Henriksen, Bradley S.; Chan, Gary; Hoffman, Robert O.; Sharifzadeh, Mohsen; Ermakov, Igor V.; Gellermann, Werner; Bernstein, Paul S.

    2013-01-01

    Purpose. Deposition of the macular pigment carotenoids lutein and zeaxanthin in the human retina occurs early in life. In this study, we examined the interrelationships of maternal carotenoid status and newborn infant macular pigment levels and systemic carotenoid status. As a secondary measure, we also evaluated the effects of intrauterine growth restriction (IUGR) on carotenoid status in term newborn infants. Methods. We measured mother and infant skin carotenoids using resonance Raman spectroscopy (RRS), serum carotenoids by HPLC, and mother breast milk carotenoids by HPLC. We measured infant macular pigment levels using noninvasive blue light reflectometry. Results. We enrolled 30 healthy term infants, their mothers, and 10 IUGR infants and their mothers. A subset of 16 infants was imaged for macular pigment optical density (MPOD). Infant serum zeaxanthin levels correlated with MPOD (r = 0.68, P = 0.007). Mother serum zeaxanthin levels correlated with infant MPOD (r = 0.59, P = 0.032). Infant and mother serum lutein did not correlate with MPOD. Mother–infant correlations were found for total serum carotenoids (r = 0.42, P = 0.020) and skin carotenoids (r = 0.48, P = 0.001). No difference was seen between IUGR infants and controls in total serum or skin carotenoids. Mothers of IUGR infants had lower total serum carotenoids (P = 0.019) and breast milk carotenoids than controls (P = 0.006). Conclusions. Our findings suggest that maternal zeaxanthin status may play a more important role than lutein status in macular pigment deposition in utero. Controlled trials are needed to determine whether maternal zeaxanthin prenatal supplementation can raise infant macular pigment levels and/or improve ocular function. PMID:23838770

  4. Interrelationships between maternal carotenoid status and newborn infant macular pigment optical density and carotenoid status.

    PubMed

    Henriksen, Bradley S; Chan, Gary; Hoffman, Robert O; Sharifzadeh, Mohsen; Ermakov, Igor V; Gellermann, Werner; Bernstein, Paul S

    2013-08-15

    Deposition of the macular pigment carotenoids lutein and zeaxanthin in the human retina occurs early in life. In this study, we examined the interrelationships of maternal carotenoid status and newborn infant macular pigment levels and systemic carotenoid status. As a secondary measure, we also evaluated the effects of intrauterine growth restriction (IUGR) on carotenoid status in term newborn infants. We measured mother and infant skin carotenoids using resonance Raman spectroscopy (RRS), serum carotenoids by HPLC, and mother breast milk carotenoids by HPLC. We measured infant macular pigment levels using noninvasive blue light reflectometry. We enrolled 30 healthy term infants, their mothers, and 10 IUGR infants and their mothers. A subset of 16 infants was imaged for macular pigment optical density (MPOD). Infant serum zeaxanthin levels correlated with MPOD (r = 0.68, P = 0.007). Mother serum zeaxanthin levels correlated with infant MPOD (r = 0.59, P = 0.032). Infant and mother serum lutein did not correlate with MPOD. Mother-infant correlations were found for total serum carotenoids (r = 0.42, P = 0.020) and skin carotenoids (r = 0.48, P = 0.001). No difference was seen between IUGR infants and controls in total serum or skin carotenoids. Mothers of IUGR infants had lower total serum carotenoids (P = 0.019) and breast milk carotenoids than controls (P = 0.006). Our findings suggest that maternal zeaxanthin status may play a more important role than lutein status in macular pigment deposition in utero. Controlled trials are needed to determine whether maternal zeaxanthin prenatal supplementation can raise infant macular pigment levels and/or improve ocular function.

  5. 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%.

  6. Fluorescence lifetime imaging of skin cancer

    NASA Astrophysics Data System (ADS)

    Patalay, Rakesh; Talbot, Clifford; Munro, Ian; Breunig, Hans Georg; König, Karsten; Alexandrov, Yuri; Warren, Sean; Neil, Mark A. A.; French, Paul M. W.; Chu, Anthony; Stamp, Gordon W.; Dunsby, Chris

    2011-03-01

    Fluorescence intensity imaging and fluorescence lifetime imaging microscopy (FLIM) using two photon microscopy (TPM) have been used to study tissue autofluorescence in ex vivo skin cancer samples. A commercially available system (DermaInspect®) was modified to collect fluorescence intensity and lifetimes in two spectral channels using time correlated single photon counting and depth-resolved steady state measurements of the fluorescence emission spectrum. Uniquely, image segmentation has been used to allow fluorescence lifetimes to be calculated for each cell. An analysis of lifetime values obtained from a range of pigmented and non-pigmented lesions will be presented.

  7. Mediator MED23 Links Pigmentation and DNA Repair through the Transcription Factor MITF.

    PubMed

    Xia, Min; Chen, Kun; Yao, Xiao; Xu, Yichi; Yao, Jiaying; Yan, Jun; Shao, Zhen; Wang, Gang

    2017-08-22

    DNA repair is related to many physiological and pathological processes, including pigmentation. Little is known about the role of the transcriptional cofactor Mediator complex in DNA repair and pigmentation. Here, we demonstrate that Mediator MED23 plays an important role in coupling UV-induced DNA repair to pigmentation. The loss of Med23 specifically impairs the pigmentation process in melanocyte-lineage cells and in zebrafish. Med23 deficiency leads to enhanced nucleotide excision repair (NER) and less DNA damage following UV radiation because of the enhanced expression and recruitment of NER factors to chromatin for genomic stability. Integrative analyses of melanoma cells reveal that MED23 controls the expression of a melanocyte master regulator, Mitf, by modulating its distal enhancer activity, leading to opposing effects on pigmentation and DNA repair. Collectively, the Mediator MED23/MITF axis connects DNA repair to pigmentation, thus providing molecular insights into the DNA damage response and skin-related diseases. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  8. Raman spectroscopy of skin neoplasms

    NASA Astrophysics Data System (ADS)

    Moryatov, A. A.; Kozlov, S. V.; Kaganov, O. I.; Orlov, A. E.; Zaharov, V. P.; Batrachenko, I. A.; Artemiev, D. N.; Blinov, N. V.

    2017-09-01

    Skin melanoma is spread inhomogeneously worldwide, particularly in Samara region there are high figures of skin neoplasms sick rate as well—18.6%. Research goal: to develop a new method of early non-invasive differential diagnostics of skin neoplasms. Registration of Raman spectrum was implemented in the distance of 3-4 mm, the spectrum registration from pathologically changed zone was subsequently conducted, then from healthy skin zone. The test time for 1 patient was no longer than 3-5 min. In a range of experiments ex vivo there were the following results: melanoma—24, basal cell cancer—25, squamosus cell sarcinoma—7, nevus pigmentosis—9, other malignant neoplasms—6; in vivo: melanoma—9, basal cell cancer—8, nevus pigmentosis—2, other benign neoplasms—2. The first results of the research dedicated to studying permissive opportunities of Raman spectroscopy, with successive two-phase analysis of received parameters display high efficiency of method of differential diagnostic for skin melanoma and other malignant neoplasms, pigment and benign skin neoplasms. Safety and rapidity of the research reveal a high potential of the technique.

  9. Chronic Central Serous Chorioretinopathy in a Patient with Pigment Dispersion Syndrome: A Possible Correlation.

    PubMed

    Kourkoutas, Dimitrios; Tsakonas, George; Karamaounas, Aristotelis; Karamaounas, Nikolaos

    2017-01-01

    Chronic central serous chorioretinopathy (CSCR) is a progressive chorioretinopathy with widespread atrophic RPE abnormalities and serous retinal detachments (SRDs) present for 6 months or longer. We report a case of CSCR in a 38-year-old patient with Pigment Dispersion Syndrome (PDS). In the presented case of CSCR, the chronic course of the disease may in part be associated with an underlying generalized degenerative dysfunction of the pigmented cells of the eye on grounds of PDS. We suggest that a chronic course of disease may be suspected in the setting of CSCR with concurrent RPE pathology, such as what is found in PDS.

  10. Tooth - abnormal shape

    MedlinePlus

    Hutchinson incisors; Abnormal tooth shape; Peg teeth; Mulberry teeth; Conical teeth ... The appearance of normal teeth varies, especially the molars. ... conditions. Specific diseases can affect tooth shape, tooth ...

  11. Dermoscopy of pigmented lesions on mucocutaneous junction and mucous membrane.

    PubMed

    Lin, J; Koga, H; Takata, M; Saida, T

    2009-12-01

    The dermoscopic features of pigmented lesions on the mucocutaneous junction and mucous membrane are different from those on hairy skin. Differentiation between benign lesions and malignant melanomas of these sites is often difficult. To define the dermoscopic patterns of lesions on the mucocutaneous junction and mucous membrane, and assess the applicability of standard dermoscopic algorithms to these lesions. An unselected consecutive series of 40 lesions on the mucocutaneous junction and mucous membrane was studied. All the lesions were imaged using dermoscopy devices, analysed for dermoscopic patterns and scored with algorithms including the ABCD rule, Menzies method, 7-point checklist, 3-point checklist and the CASH algorithm. Benign pigmented lesions of the mucocutaneous junction and mucous membrane frequently presented a dotted-globular pattern (25%), a homogeneous pattern (25%), a fish scale-like pattern (18.8%) and a hyphal pattern (18.8%), while melanomas of these sites showed a multicomponent pattern (75%) and a homogeneous pattern (25%). The fish scale-like pattern and hyphal pattern were considered to be variants of the ring-like pattern. The sensitivities of the ABCD rule, Menzies method, 7-point checklist, 3-point checklist and CASH algorithm in diagnosing mucosal melanomas were 100%, 100%, 63%, 88% and 100%; and the specificities were 100%, 94%, 100%, 94% and 100%, respectively. The ring-like pattern and its variants (fish scale-like pattern and hyphal pattern) are frequently observed as well as the dotted-globular pattern and homogeneous pattern in mucosal melanotic macules. The algorithms for pigmented lesions on hairy skin also apply to those on the mucocutaneous junction and mucous membrane with high sensitivity and specificity.

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

    PubMed

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

    2015-11-12

    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.

  14. Skin Diseases: Skin Health and Skin Diseases

    MedlinePlus

    ... The two most common types are basal cell cancer and squamous cell cancer. Melanoma, a more serious type of skin ... The two most common types are basal cell cancer and squamous cell cancer. They usually form on the head, face, ...

  15. [Preparation and component analysis of tea pigments].

    PubMed

    Li, Daxiang; Wan, Xiaochun; Xia, Tao

    2004-11-01

    To prepare tea pigments. Tea pigments are prepared by solvent extraction from Sri lanka black tea. Tea pigments contains the components as follows: caffeine 1.77%, epigallocatechin 1.37%, catechin 1.20%, epicatechin 9.55%, epigallocatechin gallate 10.52%, epicatechin gallate 9.94%, theaflavin 10.34%, theaflavin monogallate 9.57%, theaflavin digallate 4.81%, thearubigin about 40.93%. The best proportions of the compound that are obtained with HPLC analysis.

  16. Dense pigmentation of the posterior lens capsule associated with the pigment dispersion syndrome.

    PubMed

    Lin, Danny Y; Volpicelli, Mark; Singh, Kuldev

    2003-12-01

    To report an unusual case of pigment dispersion syndrome associated with unilateral dense pigmentation of the posterior lens capsule. Case report. A 59-year-old male with bilateral pigment dispersion syndrome presented with progressive decrease in visual acuity in the left eye over the past 10 to 20 years. Clinical examination revealed the typical findings of pigment dispersion syndrome including the presence of bilateral Krunkenberg spindles, iris transillumination defects, and heavy trabecular meshwork pigmentation. Of note, there was remarkably dense pigmentation of the posterior lens capsule in the eye with decreased visual acuity. Pigmentation of the posterior lens capsule may be a rare finding associated with pigment dispersion syndrome. Such a finding suggests that there may be aqueous flow into the retrolental space in some patients with this condition. The optimal treatment of this unusual condition remains undetermined.

  17. Impact of long-wavelength UVA and visible light on melanocompetent skin.

    PubMed

    Mahmoud, Bassel H; Ruvolo, Eduardo; Hexsel, Camile L; Liu, Yang; Owen, Michael R; Kollias, Nikiforos; Lim, Henry W; Hamzavi, Iltefat H

    2010-08-01

    The purpose of this study was to determine the effect of visible light on the immediate pigmentation and delayed tanning of melanocompetent skin; the results were compared with those induced by long-wavelength UVA (UVA1). Two electromagnetic radiation sources were used to irradiate the lower back of 20 volunteers with skin types IV-VI: UVA1 (340-400 nm) and visible light (400-700 nm). Pigmentation was assessed by visual examination, digital photography with a cross-polarized filter, and diffused reflectance spectroscopy at 7 time points over a 2-week period. Confocal microscopy and skin biopsies for histopathological examination using different stains were carried out. Irradiation was also carried out on skin type II. Results showed that although both UVA1 and visible light can induce pigmentation in skin types IV-VI, pigmentation induced by visible light was darker and more sustained. No pigmentation was observed in skin type II. The quality and quantity of pigment induced by visible light and UVA1 were different. These findings have potential implications on the management of photoaggravated pigmentary disorders, the proper use of sunscreens, and the treatment of depigmented lesions.

  18. Evolution of vertebrate visual pigments.

    PubMed

    Bowmaker, James K

    2008-09-01

    The visual pigments of vertebrates evolved about 500 million years ago, before the major evolutionary step of the development of jaws. Four spectrally distinct classes of cone opsin evolved through gene duplication, followed by the rod opsin class that arose from the duplication of the middle-wave-sensitive cone opsin. All four cone classes are present in many extant teleost fish, reptiles and birds, but one or more classes have been lost in primitive fish, amphibians and mammals. Gene duplication within the cone classes, especially in teleosts, has resulted in multiple opsins being available, both temporally and spatially, during development.

  19. Preparation of nearly monodisperse nanoscale inorganic pigments.

    PubMed

    Wang, Dingsheng; Liang, Xin; Li, Yadong

    2006-07-17

    Many different important commercial pigments have been synthesized based on the liquid-solid-solution (LSS) phase-transfer and separation process. Transmission electron microscopy (TEM) measurement results show that they are very small in size and have a narrow size distribution. Visible absorption spectra were taken to examine the very pure and brilliant colors of the pigments. They can be well-dispersed in cyclohexane and remain non-agglomerated, even over several months. These nearly monodisperse nanoscale inorganic pigments may have wide applications in many important fields and could bring about new developments in the pigment industry.

  20. 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.

  1. Cardiac Abnormalities in Primary Hyperoxaluria

    PubMed Central

    Mookadam, Farouk; Smith, Travis; Jiamsripong, Panupong; Moustafa, Sherif E; Monico, Carla G.; Lieske, John C.; Milliner, Dawn S.

    2018-01-01

    Background In patients with primary hyperoxaluria (PH), oxalate overproduction can result in recurrent urolithiasis and nephrocalcinosis, which in some cases results in a progressive decline in renal function, oxalate retention, and systemic oxalosis involving bone, retina, arterial media, peripheral nerves, skin, and heart. Oxalosis involving the myocardium or conduction system can potentially lead to heart failure and fatal arrhythmias. Methods and Results A retrospective review of our institution’s database was conducted for all patients with a confirmed diagnosis of PH between 1/1948 and 1/2006 (n=103). Electrocardiogram (ECG) and echocardiography were used to identify cardiac abnormalities. Ninety-three patients fulfilled the inclusion criteria, 58% were male. Mean follow-up was 11.9 (median 8.8) years. In 38 patients who received an ECG or echocardiography, 31 were found to have any cardiac abnormalities. Cardiac findings correlated with decline in renal function. Conclusions Our data suggests that physicians caring for patients with PH should pay close attention to cardiac status, especially if renal function is impaired. PMID:20921818

  2. 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

  3. Pigment phenotype and biogeographical ancestry from ancient skeletal remains: inferences from multiplexed autosomal SNP analysis.

    PubMed

    Bouakaze, Caroline; Keyser, Christine; Crubézy, Eric; Montagnon, Daniel; Ludes, Bertrand

    2009-07-01

    In the present study, a multiplexed genotyping assay for ten single nucleotide polymorphisms (SNPs) located within six pigmentation candidate genes was developed on modern biological samples and applied to DNA retrieved from 25 archeological human remains from southern central Siberia dating from the Bronze and Iron Ages. SNP genotyping was successful for the majority of ancient samples and revealed that most probably had typical European pigment features, i.e., blue or green eye color, light hair color and skin type, and were likely of European individual ancestry. To our knowledge, this study reports for the first time the multiplexed typing of autosomal SNPs on aged and degraded DNA. By providing valuable information on pigment traits of an individual and allowing individual biogeographical ancestry estimation, autosomal SNP typing can improve ancient DNA studies and aid human identification in some forensic casework situations when used to complement conventional molecular markers.

  4. 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 Central

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

    2015-01-01

    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

  5. 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

  6. Abnormal findings in peers during skills learning.

    PubMed

    Wearn, Andy; Nakatsuji, Miriam; Bhoopatkar, Harsh

    2017-02-01

    Peer physical examination (PPE), where students examine each other, is common in contemporary clinical skills learning. A range of benefits and risks have been explored in the literature. One persistent concern has been the identification and management of abnormal physical findings. Two previous studies have attempted to quantify the risk, one through the discussion of two exemplar cases and the other with a retrospective student survey. Here, we report the first prospective study of the number and type of abnormalities encountered as part of early clinical skills learning in a medical programme. We have a formal written consent process for PPE, which includes the management of abnormal findings through the completion of an event form. Our data come from cohorts undertaking years 2 and 3 of the programme between 2003 and 2014. One persistent concern (of PPE) has been the identification and management of abnormal physical findings RESULTS: Nineteen event forms were completed over this period. The incidence rates per year ranged from 0.23 to 1.05 per cent. Abnormal findings included raised blood pressure, heart murmur, abnormal bedside test values, and eye and skin conditions. The low event rate, along with a feasible process for dealing with this issue, goes some way to reassuring those with concerns. We acknowledge that some abnormalities may have been missed, and that some data may have been lost as a result of incorrect process; however, even the highest annual rate is low in absolute terms. We recommend a formal process for managing abnormalities. Ideally this would be part of an overall PPE written policy, communicated to students, enacted by tutors and approved by the local ethics committee. © 2016 John Wiley & Sons Ltd.

  7. Down-regulated PAR-2 is associated in part with interrupted melanosome transfer in pigmented basal cell epithelioma.

    PubMed

    Sakuraba, Kazuko; Hayashi, Nobukazu; Kawashima, Makoto; Imokawa, Genji

    2004-08-01

    In pigmented basal cell epithelioma (BCE), there seems to be an abnormal transfer of melanized melanosomes from proliferating melanocytes to basaloid tumor cells. In this study, the interruption of that melanosome transfer was studied with special respect to the altered function of a phagocytic receptor, protease-activated receptor (PAR)-2 in the basaloid tumor cells. We used electron microscopy to clarify the disrupted transfer at the ultrastructural level and then performed immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR) to examine the regulation of a phagocytic receptor, PAR-2, expressed on basaloid tumor cells. Electron microscopic analysis revealed that basaloid tumor cells of pigmented BCE have a significantly lower population of melanosomes ( approximately 16.4%) than do normal keratinocytes located in the perilesional normal epidermis ( approximately 91.0%). In contrast, in pigmented seborrheic keratosis (SK), a similarly pigmented epidermal tumor, the distribution of melanin granules does not differ between the lesional ( approximately 93.9%) and the perilesional normal epidermis ( approximately 92.2 %), indicating that interrupted melanosome transfer occurs in BCE but not in all pigmented epithelial tumors. RT-PCR analysis demonstrated that the expression of PAR-2 mRNA transcripts in basaloid cells is significantly decreased in pigmented BCE compared with the perilesional normal epidermis. In contrast, in pigmented SK, where melanosome transfer to basaloid tumor cells is not interrupted, the expression of PAR-2 mRNA transcripts is comparable between the basaloid tumor cells and the perilesional normal epidermis. Immunohistochemistry demonstrated that basaloid cells in pigmented BCE have less immunostaining for PAR-2 than do keratinocytes in the perilesional normal epidermis whereas in pigmented SK, there is no difference in immunostaining for PAR-2 between the basaloid tumor and the perilesional normal epidermis. These

  8. Melatonin and human skin aging

    PubMed Central

    Kleszczynski, Konrad; Fischer, Tobias W.

    2012-01-01

    Like the whole organism, skin follows the process of aging during life-time. Additional to internal factors, several environmental factors, such as solar radiation, considerably contribute to this process. While fundamental mechanisms regarding skin aging are known, new aspects of anti-aging agents such as melatonin are introduced. Melatonin is a hormone produced in the glandula pinealis that follows a circadian light-dependent rhythm of secretion. It has been experimentally implicated in skin functions such as hair cycling and fur pigmentation, and melatonin receptors are expressed in many skin cell types including normal and malignant keratinocytes, melanocytes and fibroblasts. It possesses a wide range of endocrine properties as well as strong antioxidative activity. Regarding UV-induced solar damage, melatonin distinctly counteracts massive generation of reactive oxygen species, mitochondrial and DNA damage. Thus, there is considerable evidence for melatonin to be an effective anti-skin aging compound, and its various properties in this context are described in this review. PMID:23467217

  9. Skin (image)

    MedlinePlus

    ... of the body. The skin and its derivatives (hair, nails, sweat and oil glands) make up the integumentary system. One of the main functions of the skin is protection. It protects the body from external factors such as bacteria, chemicals, and temperature.

  10. Development of a forensic skin colour predictive test.

    PubMed

    Maroñas, Olalla; Phillips, Chris; Söchtig, Jens; Gomez-Tato, Antonio; Cruz, Raquel; Alvarez-Dios, José; de Cal, María Casares; Ruiz, Yarimar; Fondevila, Manuel; Carracedo, Ángel; Lareu, María V

    2014-11-01

    There is growing interest in skin colour prediction in the forensic field. However, a lack of consensus approaches for recording skin colour phenotype plus the complicating factors of epistatic effects, environmental influences such as exposure to the sun and unidentified genetic variants, present difficulties for the development of a forensic skin colour predictive test centred on the most strongly associated SNPs. Previous studies have analysed skin colour variation in single unadmixed population groups, including South Asians (Stokowski et al., 2007, Am. J. Hum. Genet, 81: 1119-32) and Europeans (Jacobs et al., 2013, Hum Genet. 132: 147-58). Nevertheless, a major challenge lies in the analysis of skin colour in admixed individuals, where co-ancestry proportions do not necessarily dictate any one person's skin colour. Our study sought to analyse genetic differences between African, European and admixed African-European subjects where direct spectrometric measurements and photographs of skin colour were made in parallel. We identified strong associations to skin colour variation in the subjects studied from a pigmentation SNP discovery panel of 59 markers and developed a forensic online classifier based on naïve Bayes analysis of the SNP profiles made. A skin colour predictive test is described using the ten most strongly associated SNPs in 8 genes linked to skin pigmentation variation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  11. Molecular imaging of melanin distribution in vivo and quantitative differential diagnosis of human pigmented lesions using label-free harmonic generation biopsy (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Sun, Chi-Kuang; Wei, Ming-Liang; Su, Yu-Hsiang; Weng, Wei-Hung; Liao, Yi-Hua

    2017-02-01

    Harmonic generation microscopy is a noninvasive repetitive imaging technique that provides real-time 3D microscopic images of human skin with a sub-femtoliter resolution and high penetration down to the reticular dermis. In this talk, we show that with a strong resonance effect, the third-harmonic-generation (THG) modality provides enhanced contrast on melanin and allows not only differential diagnosis of various pigmented skin lesions but also quantitative imaging for longterm tracking. This unique capability makes THG microscopy the only label-free technique capable of identifying the active melanocytes in human skin and to image their different dendriticity patterns. In this talk, we will review our recent efforts to in vivo image melanin distribution and quantitatively diagnose pigmented skin lesions using label-free harmonic generation biopsy. This talk will first cover the spectroscopic study on the melanin enhanced THG effect in human cells and the calibration strategy inside human skin for quantitative imaging. We will then review our recent clinical trials including: differential diagnosis capability study on pigmented skin tumors; as well as quantitative virtual biopsy study on pre- and post- treatment evaluation on melasma and solar lentigo. Our study indicates the unmatched capability of harmonic generation microscopy to perform virtual biopsy for noninvasive histopathological diagnosis of various pigmented skin tumors, as well as its unsurpassed capability to noninvasively reveal the pathological origin of different hyperpigmentary diseases on human face as well as to monitor the efficacy of laser depigmentation treatments. This work is sponsored by National Health Research Institutes.

  12. 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)

  13. 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. © 2014 Japanese Dermatological Association.

  14. 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.

  15. High Throughput, High Content Screening for Novel Pigmentation Regulators Using a Keratinocyte/Melanocyte Co-culture System

    PubMed Central

    Lee, Ju Hee; Chen, Hongxiang; Kolev, Vihren; Aull, Katherine H.; Jung, Inhee; Wang, Jun; Miyamoto, Shoko; Hosoi, Junichi; Mandinova, Anna; Fisher, David E.

    2014-01-01

    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 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 4,000 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. PMID:24438532

  16. "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)

  17. Skin melanocytes: biology and development

    PubMed Central

    Wachulska, Małgorzata; Stasiewicz, Aneta; Tymińska, Agata

    2013-01-01

    In the human skin, melanocytes are present in the epidermis and hair follicles. The basic features of these cells are the ability to melanin production and the origin from neural crest cells. This last element is important because there are other cells able to produce melanin but of different embryonic origin (pigmented epithelium of retina, some neurons, adipocytes). The life cycle of melanocyte consists of several steps including differentiation of melanocyte lineage/s from neural crest, migration and proliferation of melanoblasts, differentiation of melanoblasts into melanocytes, proliferation and maturation of melanocytes at the target places (activity of melanogenic enzymes, melanosome formation and transport to keratinocytes) and eventual cell death (hair melanocytes). Melanocytes of the epidermis and hair are cells sharing some common features but in general they form biologically different populations living in unique niches of the skin. PMID:24278043

  18. 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. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  19. Kaolin-based foliar reflectant and water deficit influence Malbec leaf and berry temperature, pigments, and photosynthesis

    USDA-ARS?s Scientific Manuscript database

    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...

  20. Newborn Skin: Common Skin Problems.

    PubMed

    Kutlubay, Zekayi; Tanakol, Ali; Engýn, Burhan; Onel, Cristina; Sýmsek, Ersin; Serdaroglu, Server; Tuzun, Yalçýn; Yilmaz, Erkan; Eren, Bülent

    2017-01-01

    The newborn skin can be separated from adult's skin in several ways. In dermatologic examination it can be easily observed that it is thinner, less hairy and has less sweat and sebaceous gland secretions. These differentiations present especially in preterm newborns. Their skin is exposed to mechanical trauma, bacteria and weather, heat alterations. At birth, newborn skin is protected by the coverage of vernix caseosa, which has lubricating and antibacterial features and its pH ranges from 6.7 to 7.4. Beneath the vernix caseosa the skin has a pH of 5.5-6.0. In newborn dermatologic examination it is very important to distinguish transient benign dermatoses and severe diseases, make early diagnosis and treat congenital skin disorders. Although the benign cases are common in this life period, clinical presentations can be much more exaggerated, dramatic and cause a great deal of anxiety to parents. Therefore, as a doctor, knowing the dermatological, pathological and non-pathological common skin rashes guides the family in the right direction, offers advice to reduce uncertainty and time for the treatment of severe conditions and builds a confidential doctor-patient relationship. In this review, our aim is to provide a general overview to common skin rashes in newborn period.

  1. Fungal and Bacterial Pigments: Secondary Metabolites with Wide Applications

    PubMed Central

    Narsing Rao, Manik Prabhu; Xiao, Min; Li, Wen-Jun

    2017-01-01

    The demand for natural colors is increasing day by day due to harmful effects of some synthetic dyes. Bacterial and fungal pigments provide a readily available alternative source of naturally derived pigments. In contrast to other natural pigments, they have enormous advantages including rapid growth, easy processing, and independence of weather conditions. Apart from colorant, bacterial and fungal pigments possess many biological properties such as antioxidant, antimicrobial and anticancer activity. This review outlines different types of pigments. It lists some bacterial and fungal pigments and current bacterial and fungal pigment status and challenges. It also focuses on possible fungal and bacterial pigment applications. PMID:28690593

  2. The genetic architecture of normal variation in human pigmentation: an evolutionary perspective and model.

    PubMed

    McEvoy, Brian; Beleza, Sandra; Shriver, Mark D

    2006-10-15

    Skin pigmentation varies substantially across human populations in a manner largely coincident with ultraviolet radiation intensity. This observation suggests that natural selection in response to sunlight is a major force in accounting for pigmentation variability. We review recent progress in identifying the genes controlling this variation with a particular focus on the trait's evolutionary past and the potential role of testing for signatures of selection in aiding the discovery of functionally important genes. We have analyzed SNP data from the International HapMap project in 77 pigmentation candidate genes for such signatures. On the basis of these results and other similar work, we provide a tentative three-population model (West Africa, East Asia and North Europe) of the evolutionary-genetic architecture of human pigmentation. These results suggest a complex evolutionary history, with selection acting on different gene targets at different times and places in the human past. Some candidate genes may have been selected in the ancestral human population, others in the 'out of Africa' proto European-Asian population, whereas most appear to have selectively evolved solely in either Europeans or East Asians separately despite the pigmentation similarities between these two populations. Selection signatures can provide important clues to aid gene discovery. However, these should be viewed as complements, rather than replacements of, functional studies including linkage and association analyses, which can directly refine our understanding of the trait.

  3. Effects of skin rehabilitation massage therapy on pruritus, skin status, and depression in burn survivors.

    PubMed

    Roh, Young Sook; Cho, Hee; Oh, Jung Ok; Yoon, Cheon Jae

    2007-03-01

    Hypertrophic scarring and depression are the principal problems of burn rehabilitation. This study was done to verify the effects of skin rehabilitation massage therapy (SRMT) on pruritus, skin status, and depression for Korean burn survivors. A pretest-posttest design using a nonequivalent control group was applied to examine the effects of SRMT for 3 months in a group of 18 burn survivors. The major dependent variables-including pruritus, objective and subjective scar status, and depression-were measured at the beginning and at the end of the therapy to examine the effects of SRMT. Burn survivors receiving SRMT showed reduced pruritus, improved skin status, and depression. The remaining scar also showed improvement in skin pigmentation, pliability, vascularity, and height (compared to the surrounding skin) as measured on the Vancouver Scar Scale (VSS). The findings demonstrate that SRMT for burn survivors may improve their scars both objectively and subjectively, and also reduce pruritus and depression.

  4. Tips and tricks in the dermoscopy of pigmented lesions

    PubMed Central

    2012-01-01

    Dermoscopy is a useful, widely used tool for examining pigmented lesions, especially helpful in cases of an uncertain nature. Nevertheless, doctors may experience diagnostic difficulties while using this method. An example of this may be found in the examination of subcorneal hematoma, dark nevi with black lamella or lesions of acral volar skin. In such cases, a few diagnostic tricks have proven to be helpful in achieving diagnostic accuracy. This paper reviews various methods of performing dermoscopy, suggesting a number of simple, yet helpful tests. These include the adhesive tape test, the skin scraping test and the ink furrow test. The adhesive tape test is helpful in differentiating between dark melanocytic nevi and melanoma. Hematoma may be more easily differentiated with the use of the so-called skin scraping test. The confirmation of benign and melanocytic lesions of acral volar skin, on the other hand, is more accurate when using the ink furrow test. These methods have been discussed here based upon a series of literature reviews, the authors’ own experience and, also, iconography. The present article describes novel methods used in dermoscopy, helping to bring about a faster, more accurate diagnostics of those lesions which have proven to be more difficult to recognize. Helpful tricks, such as have been known to professional literature, as well as the authors’ own experience (for instance, applying urea cream to hyperkeratotic lesions or using photographs of skin lesions taken with the aid of a mobile phone camera – all prior to surgery) will surely be considered beneficial to the practitioner, be it dermatologist or any other physician. PMID:22916721

  5. Skin Cancer in Skin of Color

    PubMed Central

    Bradford, Porcia T.

    2009-01-01

    Skin cancers in skin of color often present atypically or with advanced stage in comparison to Caucasian patients. Health care providers must maintain a high index of suspicion when examining skin lesions in skin of color. PMID:19691228

  6. Ethnic variation in melanin content and composition in photoexposed and photoprotected human skin.

    PubMed

    Alaluf, Simon; Atkins, Derek; Barrett, Karen; Blount, Margaret; Carter, Nik; Heath, Alan

    2002-04-01

    We have examined the quantity and composition of melanin in both photoprotected (volar upper arm) and chronically photoexposed (dorsal forearm) skin from a range of different ethnic skin types including African, Indian, Mexican, Chinese and European. The most lightly pigmented (European, Chinese and Mexican) skin types have approximately half as much epidermal melanin as the most darkly pigmented (African and Indian) skin types. However, the composition of melanin in these lighter skin types is comparatively more enriched with lightly coloured, alkali-soluble melanin components (up to three-fold). Regardless of ethnicity, epidermal melanin content is significantly greater in chronically photoexposed skin than it is in corresponding photoprotected skin (up to two-fold). However, by comparison there is only a modest enrichment of lightly coloured, alkali soluble melanin components in photoprotected skin (up to 1.3-fold). Analysis of melanosomes extracted from the epidermis in these subjects indicates that the proportion of spheroidal melanosomes is low in all skin types examined (<10%). This suggests that in human skin, pheomelanin is a very minor component of epidermal melanin, even in the lightest (European) skin types. Analysis of melanosome size revealed a significant and progressive variation in size with ethnicity: African skin having the largest melanosomes followed in turn by Indian, Mexican, Chinese and European. On the basis of these findings, we propose that variation in skin pigmentation is strongly influenced by both the amount and the composition (or colour) of the melanin in the epidermis. Variation in melanosome size may also play a significant role. However, the data also suggest that in human skin there are subtle differences in the mechanisms associated with the maintenance of constitutive pigmentation and facultative hyperpigmentation, respectively.

  7. Hyperelastic skin

    MedlinePlus

    ... is most often seen in people who have Ehlers-Danlos syndrome. People with this disorder have very elastic skin. ... any member of your family been diagnosed with Ehlers-Danlos syndrome? What other symptoms are present? Genetic counseling may ...

  8. Skin lumps

    MedlinePlus

    ... The skin. In: Swartz MH, ed. Textbook of Physical Diagnosis: History and Examination . 7th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 5. Review Date 4/14/2017 Updated by: Kevin Berman, ...

  9. 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 ...

  10. Skin color parameters and Fitzpatrick phototypes in estimating the risk of skin cancer: A case-control study in the Polish population.

    PubMed

    Sitek, Aneta; Rosset, Iwona; Żądzińska, Elżbieta; Kasielska-Trojan, Anna; Neskoromna-Jędrzejczak, Aneta; Antoszewski, Bogusław

    2016-04-01

    Light skin pigmentation is a known risk factor for skin cancer. Skin color parameters and Fitzpatrick phototypes were evaluated in terms of their usefulness in predicting the risk of skin cancer. A case-control study involved 133 individuals with skin cancer (100 with basal cell carcinoma, 21 with squamous cell carcinoma, 12 with melanoma) and 156 healthy individuals. All of them had skin phototype determined and spectrophotometric skin color measurements were done on the inner surfaces of their arms and on the buttock. Using those data, prediction models were built and subjected to 17-fold stratified cross-validation. A model, based on skin phototypes, was characterized by area under the receiver operating characteristic curve = 0.576 and exhibited a lower predictive power than the models, which were mostly based on spectrophotometric variables describing pigmentation levels. The best predictors of skin cancer were R coordinate of RGB color space (area under the receiver operating characteristic curve 0.687) and melanin index (area under the receiver operating characteristic curve 0.683) for skin on the buttock. A small number of patients were studied. Models were not externally validated. Skin color parameters are more accurate predictors of skin cancer occurrence than skin phototypes. Spectrophotometry is a quick, easy, and affordable method offering relatively good predictive power. Copyright © 2015 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  11. The Neurofibromatosis Type 1 (Nf1) Tumor Suppressor is a Modifier of Carcinogen-Induced Pigmentation and Papilloma Formation in C57BL/6 Mice

    PubMed Central

    Atit, Radhika P.; Mitchell, Kent; Nguyen, Lam; Warshawsky, David; Ratner, Nancy

    2010-01-01

    There is increasing evidence implicating the human NF1 gene in epithelial carcinogenesis. To test if NF1 can play a part in skin tumor formation, we analyzed effects of the skin cancer initiator dimethylbenzanthracene and/or the tumor promoter 12-O-tetradecanoyl-13-acetylphorbol on mice heterozygous for null mutations in Nf1 (Nf1+/−). Mice were on the C57BL/6 background, noted for resistance to chemical carcinogens. Nf1+/− mice (18 of 24) developed papillomas after treatment with dimethylbenzanthracene and 12-O-tetradecanoyl-13-acetylphorbol; papillomas did not develop in wild-type C57BL/6 mice nor Nf1+/− mice treated with 12-O-tetradecanoyl-13-acetylphorbol alone. All papillomas analyzed (six of six) had mutations in codon 61 of H-ras, demonstrating strong cooperation between the Nf1 GTPase activating protein for Ras, neurofibromin, and Ras-GTP. After exposure to 12-O-tetradecanoyl-13-acetylphorbol, Nf1+/− keratinocytes showed significant, sustained, increases in proliferation, implicating Nf1 in phorbol ester responsive pathways. Thus, Nf1 levels regulate the response of keratinocytes to 12-O-tetradecanoyl-13-acetylphorbol. Nf1+/− mice also showed a 2-fold increase in the development of pigmented skin patches stimulated by dimethylbenzanthracene; patches were characterized by hair follicles in anagen phase, implicating keratinocytes in the aberrant hyperpigmentation. Our results show that mutation in the Nf1 gene causes abnormal keratinocyte proliferation that can be revealed by environmental assaults such as carcinogen exposure. The data support a plausible role for NF1 mutation in human epithelial carcinogenesis. PMID:10844550

  12. 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.

  13. Genetic and Virulent Difference Between Pigmented and Non-pigmented Staphylococcus aureus.

    PubMed

    Zhang, Jing; Suo, Yujuan; Zhang, Daofeng; Jin, Fangning; Zhao, Hang; Shi, Chunlei

    2018-01-01

    Staphyloxanthin (STX), a golden carotenoid pigment produced by Staphylococcus aureus , is suggested to act as an important virulence factor due to its antioxidant properties. Restraining biosynthesis of STX was considered as an indicator of virulence decline in pigmented S. aureus isolates. However, it is not clear whether natural non-pigmented S. aureus isolates have less virulence than pigmented ones. In this study, it is aimed to compare the pigmented and non-pigmented S. aureus isolates to clarify the genetic and virulent differences between the two groups. Here, 132 S. aureus isolates were divided into two phenotype groups depending on the absorbance (OD 450 ) of the extracted carotenoids. Then, all isolates were subjected to spa typing and multilocus sequence typing (MLST), and then the detection of presence of 30 virulence factors and the gene integrity of crtN and crtM . Furthermore, 24 typical S. aureus isolates and 4 S. argenteus strains were selected for the murine infection assay of in vivo virulence, in which the histological observation and enumeration of CFUs were carried out. These isolates were distributed in 26 sequence types (STs) and 49 spa types. The pigmented isolates were scattered in 25 STs, while the non-pigmented isolates were more centralized, which mainly belonged to ST20 (59%) and ST25 (13%). Among the 54 non-pigmented isolates, about 20% carried intact crtN and crtM genes. The in vivo assay suggested that comparing with pigmented S. aureus , non-pigmented S. aureus and S. argenteus strains did not show a reduced virulence in murine sepsis models. Therefore, it suggested that there were no significant genetic and virulent differences between pigmented and non-pigmented S. aureus .

  14. 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 tenfoldmore » 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.« less

  15. Experimental study on skin irritation of bone spur powder on rabbit

    NASA Astrophysics Data System (ADS)

    Ma, Zhenzhen; Zhang, Xuhui; Hao, Shaojun; Shen, Huiling; Wang, Huamin; Ji, Xianghui; Zhang, Zhengchen; Huang, Youling

    2018-04-01

    To observe the effect of bone powder of rabbit skin, provide the basis for the safety of clinical use of bone powder, 24 rabbits were randomly divided into 6 groups, complete skin test and damaged skin test each divided into 3 groups (n=4), high, low, 3 doses tested daily administered 1 times, continuous administration for 7 days, in 24 hours after the last administration of drug residues, wash with warm water, the removal of L hours after drug for 24 hours, 48 hours, 72 hours and seventh days, observed and recorded to apply position before administration and administration during the skin no erythema and edema, and observe the smear Parts of any pigmentation, bleeding, rough skin or thin skin etc., record the occurrence time and duration time. Through comparative observation, intact skin group before administration and dosing period, there were no erythema and edema, pigmentation, bleeding, rough skin or thin skin etc., there is no difference with the control group; the damaged skin group after administration of 1 to 5 days, each rabbit skin there are different degrees of erythema and edema, especially to skin injury after 24-48 hours is obvious, 2 days (48 hours) after 4 days gradually reduced, significantly subsided after 6 days, erythema and edema phenomenon subsided completely, not out of blood, pigmentation, rough skin or thin skin and so on. The bone spur powder has no irritation on the intact skin of rabbits. The bone spur powder has moderate irritation on the damaged skin of rabbits, but after 48 hours, the stimulation reaction subsided spontaneously, which is caused by the inflammatory reaction caused by skin injury, rather than the medication. The bone spur powder is safe for clinical use.

  16. The safety and efficacy of the 308-nm excimer laser for pigment correction of hypopigmented scars and striae alba.

    PubMed

    Alexiades-Armenakas, Macrene R; Bernstein, Leonard J; Friedman, Paul M; Geronemus, Roy G

    2004-08-01

    To assess the safety and efficacy of the 308-nm excimer laser in pigment correction of hypopigmented scars and striae alba. Institutional review board-approved randomized controlled trial. Private research center. Volunteer sample of 31 adult subjects with hypopigmented scars or striae alba distributed on the face, torso, or extremities. Lesions were randomized to receive treatment or not, with site-matched normal control areas. Treatments were initiated with a minimal erythema dose minus 50 mJ/cm(2) to affected areas. Subsequent treatments were performed biweekly until 50% to 75% pigment correction, then every 2 weeks thereafter until a maximum of 10 treatments, 75% increase in colorimetric measurements, or 100% visual pigment correction. Pigment correction by visual and colorimetric assessments compared with untreated control lesions and site-matched normal skin before each treatment and at 1-, 2-, 4-, and 6-month follow-up intervals. Occurrence of erythema, blistering, dyspigmentation, or other adverse effects was monitored. The percentage pigment correction by both assessments increased in direct proportion to the number of treatments. The mean percentage pigment correction by visual assessment relative to control of 61% (95% confidence interval [CI], 55%-67%) for scars and 68% (95% CI, 62%-74%) for striae was achieved after 9 treatments. The mean percentage pigmentation by colorimetric measurements relative to control of 101% (95% CI, 99%-103%) for scars and 102% (95% CI, 99%-104%) for striae was achieved after 9 treatments. Both sets of values gradually declined toward baseline levels during the 6-month follow-up. No blistering or dyspigmentation occurred. Therapy with the 308-nm excimer laser is safe and effective in pigment correction of hypopigmented scars and striae alba. Mean final pigment correction rates relative to control sites of approximately 60% to 70% by visual assessment and 100% by colorimetric analysis were observed after 9 treatments

  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. 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

  19. 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)

  20. Lenticular abnormalities in children.

    PubMed

    Khokhar, Sudarshan; Agarwal, Tushar; Kumar, Gaurav; Kushmesh, Rakhi; Tejwani, Lalit Kumar

    2012-01-01

    To study the lenticular problems in children presenting at an apex institute. Retrospective analysis of records (< 14 years) of new lens clinic cases was done. Of 1,047 children, 687 were males. Mean age at presentation was 6.35 ± 4.13 years. Developmental cataract was seen in 45.6% and posttraumatic cataract in 29.7% of patients. Other abnormalities were cataract with retinal detachment, persistent hyperplastic primary vitreous, subluxated lens, micro/spherophakia, cataract secondary to uveitis, intraocular lens complications, cataract with choroidal coloboma, and visual axis opacification. Developmental and posttraumatic cataracts were the most common abnormalities. Delayed presentation is of concern. Copyright 2012, SLACK Incorporated.

  1. Ultraviolet Radiations: Skin Defense-Damage Mechanism.

    PubMed

    Mohania, Dheeraj; Chandel, Shikha; Kumar, Parveen; Verma, Vivek; Digvijay, Kumar; Tripathi, Deepika; Choudhury, Khushboo; Mitten, Sandeep Kumar; Shah, Dilip

    2017-01-01

    UV-radiations are the invisible part of light spectra having a wavelength between visible rays and X-rays. Based on wavelength, UV rays are subdivided into UV-A (320-400 nm), UV-B (280-320 nm) and UV-C (200-280 nm). Ultraviolet rays can have both harmful and beneficial effects. UV-C has the property of ionization thus acting as a strong mutagen, which can cause immune-mediated disease and cancer in adverse cases. Numbers of genetic factors have been identified in human involved in inducing skin cancer from UV-radiations. Certain heredity diseases have been found susceptible to UV-induced skin cancer. UV radiations activate the cutaneous immune system, which led to an inflammatory response by different mechanisms. The first line of defense mechanism against UV radiation is melanin (an epidermal pigment), and UV absorbing pigment of skin, which dissipate UV radiation as heat. Cell surface death receptor (e.g. Fas) of keratinocytes responds to UV-induced injury and elicits apoptosis to avoid malignant transformation. In addition to the formation of photo-dimers in the genome, UV also can induce mutation by generating ROS and nucleotides are highly susceptible to these free radical injuries. Melanocortin 1 receptor (MC1R) has been known to be implicated in different UV-induced damages such as pigmentation, adaptive tanning, and skin cancer. UV-B induces the formation of pre-vitamin D3 in the epidermal layer of skin. UV-induced tans act as a photoprotection by providing a sun protection factor (SPF) of 3-4 and epidermal hyperplasia. There is a need to prevent the harmful effects and harness the useful effects of UV radiations.

  2. Hydrophilic interaction liquid chromatographic analysis of aminohydroxyphenylalanines from melanin pigments.

    PubMed

    Nezirević, Dzeneta; Arstrand, Kerstin; Kågedal, Bertil

    2007-09-07

    Malignant melanomas are more often seen in subjects with light colored skin who tan poorly than in persons who tan more rapidly. This has been attributed to the structure of their pigment, pheomelanin, which differs markedly from the eumelanin of persons with darker skin. To study the hydrolysis products of pheomelanin pigments a new method was developed for analysis of 4-amino-3-hydroxyphenylalanine (4-AHP) and 3-amino-4-hydroxyphenylalanine (3-AHP). Pheomelanin samples were hydrolyzed and extracted with solid-phase extraction columns using strong cation-exchange (SCX) cartridges. Separation of 4-AHP and 3-AHP was achieved on a ZIC-HILIC column (150 mm x 2.1mm I.D.) with a mobile phase consisting of acetonitrile: 0.1 M ammonium acetate buffer, pH 4.5 (82:18, v/v). Detection was performed with an electrochemical detector at +400 mV. Run time was 30 min. The limits of detection were 73 pg and 51 pg for 4-AHP and 3-AHP respectively, using 2 microl injections. Good linearity was found within the range 0.05-5.0 microg/ml. Absolute recovery was 70% and relative recovery was 100%. The AHPs were stable for 1 year in the hydrolyzed samples, for 4 days in the eluates from solid-phase sorbents stored in the refrigerator, and for 2 days diluted with mobile phase and stored in the autosampler at 10 degrees C. The within-day imprecision was <5% and the between-day imprecision was <7% for the two analytes. The method, applied to the analysis of pheomelanin in urine from human melanoma patients, allows the analysis of 30 samples in one set and is suitable for routine work with human hair and melanoma cells. By using the ZIC-HILIC stationary phase, ion-pairing reagents could be avoided, which makes the method suitable to further analysis of degradation products from pheomelanins using mass spectrometric detection.

  3. Arsenic Exposure, Dermatological Lesions, Hypertension, and Chromosomal Abnormalities among People in a Rural Community of Northwest Iran

    PubMed Central

    Dastgiri, Saeed; Fizi, Mohammad A.H.; Olfati, Nahid; Zolali, Shahin; Pouladi, Nasser; Azarfam, Parvin

    2010-01-01

    Chronic exposure to arsenic compounds is one of the major public-health problems in many developing and some developed countries. The aim of this study was to investigate the effects of chronic exposure to arsenic on dermatological lesions, hypertension, and chromosomal abnormalities among people in a community in the northwest of Iran. The occurrence of dermatological lesions, hypertension, and chromosomal abnormalities was investigated in two groups: Ghopuz village, including 101 subjects with chronic exposure to arsenic in drinking-water and Mayan village, including 107 subjects with no exposure. Daily/yearly absorbed amounts of arsenic were calculated for all subjects. Cumulative arsenic index for each individual was then estimated on the basis of age, water consumption, and location of residence. Arsenic concentration in drinking-water sources in Ghopuz and Mayan villages was 1031±1103 μg/L and non-detectable respectively. The mean systolic blood pressure in the exposure group [n=137, 95% confidence interval (CI 132–142)] was significantly higher than that in the control group (n=107, 95% CI 99.9–114). A similar significant difference was observed for diastolic blood pressure (exposed: n=82, 95% CI 79–85 vs non-exposed: n=71, 95% CI 66–75). The incidence of hyperkeratosis was 34 times higher among the exposure group compared to the control subjects [odds ratio (OR)=34, p<0.001)]. A significant difference was also observed in the occurrence of skin-pigmentation between the two groups (OR=2.4, p<0.007). Location and severity of the pigmentations were statistically different between the two groups. Twenty-five percent of the subjects in the exposure group showed chromosomal abnormalities (p=0.05). Arsenic exposure was a serious health problem in the region. More studies are needed to investigate the long-term effects and dose-response relationship of arsenic in the region and similar areas. Wide-ranging monitoring programmes for drinking-water sources

  4. Activation of muscarinic acetylcholine receptors elicits pigment granule dispersion in retinal pigment epithelium isolated from bluegill.

    PubMed

    González, Alfredo; Crittenden, Elizabeth L; García, Dana M

    2004-07-13

    In fish, melanin pigment granules in the retinal pigment epithelium disperse into apical projections as part of the suite of responses the eye makes to bright light conditions. This pigment granule dispersion serves to reduce photobleaching and occurs in response to neurochemicals secreted by the retina. Previous work has shown that acetylcholine may be involved in inducing light-adaptive pigment dispersion. Acetylcholine receptors are of two main types, nicotinic and muscarinic. Muscarinic receptors are in the G-protein coupled receptor superfamily, and five different muscarinic receptors have been molecularly cloned in human. These receptors are coupled to adenylyl cyclase, calcium mobilization and ion channel activation. To determine the receptor pathway involved in eliciting pigment granule migration, we isolated retinal pigment epithelium from bluegill and subjected it to a battery of cholinergic agents. The general cholinergic agonist carbachol induces pigment granule dispersion in isolated retinal pigment epithelium. Carbachol-induced pigment granule dispersion is blocked by the muscarinic antagonist atropine, by the M1 antagonist pirenzepine, and by the M3 antagonist 4-DAMP. Pigment granule dispersion was also induced by the M1 agonist 4-[N-(4-chlorophenyl) carbamoyloxy]-4-pent-2-ammonium iodide. In contrast the M2 antagonist AF-DX 116 and the M4 antagonist tropicamide failed to block carbachol-induced dispersion, and the M2 agonist arecaidine but-2-ynyl ester tosylate failed to elicit dispersion. Our results suggest that carbachol-mediated pigment granule dispersion occurs through the activation of Modd muscarinic receptors, which in other systems couple to phosphoinositide hydrolysis and elevation of intracellular calcium. This conclusion must be corroborated by molecular studies, but suggests Ca2+-dependent pathways may be involved in light-adaptive pigment dispersion.

  5. Comparative chemical characterization of pigmented and less pigmented cell walls of Alternaria tenuissima.

    PubMed

    Kishore, Kankipati Hara; Kanjilal, Sanjit; Misra, Sunil; Reddy, Chinnathimma Rajagopal; Murty, Upadyayula Suryanarayana

    2005-12-01

    Alternaria tenuissima, the parasitic fungus, was obtained from the pruned upper-cut surfaces of mulberry stems. This fungus contains dark pigment because of the presence of melanin in the cell wall. To obtain less-pigmented cell walls, this fungus was grown under dark condition. When the pigmented and less-pigmented cell walls were chemically analyzed, no differences were observed in amino-acid composition, hexoses, or pentoses. However, in pigmented cell walls, higher contents of melanin (2.6%) were found than in less-pigmented cell walls (0.3%). Interestingly, a significant difference was observed in the relative fatty-acid compositions between these two types of cell walls. Among the major fatty acids, there were increased concentrations of tetradecanoic acid (C14:0), hexadecanoic acid (C16:0), 9-hexadecenoic acid (C16: 1,Delta 9), and 9-octadecanoic acid (C18:1,Delta 9) and a concomitant decrease in 9,12-octadecadienoic acid (C18:2,Delta 9,12) in less-pigmented compared with pigmented cell walls. This difference in fatty-acid composition may be related to the higher percentage of melanin in the pigmented than the less-pigmented cell walls. Lesser amounts of 9,12-octadecadienoic acid in less-pigmented cell walls may have been caused by the growth of the fungus under environmental stress conditions. An interesting observation was the presence in pigmented cell walls only of methyl-substituted fatty acids with carbon numbers C14 to C17, but their occurrence could not be ascertained in the present study.

  6. Protective effect of the standardized green tea seed extract on UVB-induced skin photoaging in hairless mice

    PubMed Central

    Lim, Jae-Youn; Kim, Ok-Kyung; Lee, Jeongmin; Lee, Min-Jae; Kang, Namgil

    2014-01-01

    BACKGROUND/OBJECTIVES Ultraviolet B (UVB) irradiation on skin can induce production of reactive oxygen species (ROS), which cause expression of matrix metalloproteinases (MMPs) and collagen degradation. Thus, chronic exposure of skin to UVB irradiation leads to histological changes consistent with aging, such as wrinkling, abnormal pigmentation, and loss of elasticity. We investigated the protective effect of the standardized green tea seed extract (GSE) on UVB-induced skin photoaging in hairless mice. MATERIALS/METHODS Skin photoaging was induced by UVB irradiation on the back of Skh-1 hairless mice three times per week and UVB irradiation was performed for 10 weeks. Mice were divided into six groups; normal control, UVB irradiated control group, positive control (UVB + dietary supplement of vitamin C 100 mg/kg), GSE 10 mg/kg (UVB + dietary supplement of GSE 10 mg/kg), GSE 100 mg/kg (UVB + dietary supplement of GSE 100 mg/kg), and GSE 200 mg/kg (UVB + dietary supplement of GSE 200 mg/kg). RESULTS The dietary supplement GSE attenuated UVB irradiation-induced wrinkle formation and the decrease in density of dermal collagen fiber. In addition, results of the antioxidant analysis showed that GSE induced a significant increase in antioxidant enzyme activity compared with the UVB irradiation control group. Dietary supplementation with GSE 200 mg/kg resulted in a significant decrease in expression of MMP-1, MMP-3, and MMP-9 and an increase in expression of TIMP and type-1 collagen. CONCLUSIONS Findings of this study suggest that dietary supplement GSE could be useful in attenuation of UVB irradiation-induced skin photoaging and wrinkle formation due to regulation of antioxidant defense systems and MMPs expression. PMID:25110559

  7. Protective effect of the standardized green tea seed extract on UVB-induced skin photoaging in hairless mice.

    PubMed

    Lim, Jae-Youn; Kim, Ok-Kyung; Lee, Jeongmin; Lee, Min-Jae; Kang, Namgil; Hwang, Jae-Kwan

    2014-08-01

    Ultraviolet B (UVB) irradiation on skin can induce production of reactive oxygen species (ROS), which cause expression of matrix metalloproteinases (MMPs) and collagen degradation. Thus, chronic exposure of skin to UVB irradiation leads to histological changes consistent with aging, such as wrinkling, abnormal pigmentation, and loss of elasticity. We investigated the protective effect of the standardized green tea seed extract (GSE) on UVB-induced skin photoaging in hairless mice. Skin photoaging was induced by UVB irradiation on the back of Skh-1 hairless mice three times per week and UVB irradiation was performed for 10 weeks. Mice were divided into six groups; normal control, UVB irradiated control group, positive control (UVB + dietary supplement of vitamin C 100 mg/kg), GSE 10 mg/kg (UVB + dietary supplement of GSE 10 mg/kg), GSE 100 mg/kg (UVB + dietary supplement of GSE 100 mg/kg), and GSE 200 mg/kg (UVB + dietary supplement of GSE 200 mg/kg). The dietary supplement GSE attenuated UVB irradiation-induced wrinkle formation and the decrease in density of dermal collagen fiber. In addition, results of the antioxidant analysis showed that GSE induced a significant increase in antioxidant enzyme activity compared with the UVB irradiation control group. Dietary supplementation with GSE 200 mg/kg resulted in a significant decrease in expression of MMP-1, MMP-3, and MMP-9 and an increase in expression of TIMP and type-1 collagen. Findings of this study suggest that dietary supplement GSE could be useful in attenuation of UVB irradiation-induced skin photoaging and wrinkle formation due to regulation of antioxidant defense systems and MMPs expression.

  8. 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.

  9. Pigment Production Analysis in Human Melanoma Cells.

    PubMed

    Hopkin, Amelia Soto; Paterson, Elyse K; Ruiz, Rolando; Ganesan, Anand K

    2016-05-25

    The human epidermal melanocyte is a highly specialized pigmented cell that serves to protect the epidermis from ultraviolet (UV) damage through the production of melanin, or melanogenesis. Misregulation in melanogenesis leading to either hyper- or hypo-pigmentation is found in human diseases such as malasma and vitiligo. Current therapies for these diseases are largely unsuccessful and the need for new therapies is necessary. In order to identify genes and or compounds that can alter melanogenesis, methods are required that can detect changes in pigment production as well as expression of key melanogenesis transcription factors and enzymes. Here we describe methods to detect changes in melanogenesis in a human melanoma cell line, MNT-1, by (1) analyzing pigment production by measuring the absorbance of melanin present by spectrophotometry, (2) analyzing transcript expression of potent regulators of melanogenesis by qunatitative reverse-transcription (RT)PCR and (3) analyzing protein expression of potent regulators of melanogenesis by Western blot (WB).

  10. 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.

  11. The evolution of human skin coloration.

    PubMed

    Jablonski, N G; Chaplin, G

    2000-07-01

    Skin color is one of the most conspicuous ways in which humans vary and has been widely used to define human races. Here we present new evidence indicating that variations in skin color are adaptive, and are related to the regulation of ultraviolet (UV) radiation penetration in the integument and its direct and indirect effects on fitness. Using remotely sensed data on UV radiation levels, hypotheses concerning the distribution of the skin colors of indigenous peoples relative to UV levels were tested quantitatively in this study for the first time. The major results of this study are: (1) skin reflectance is strongly correlated with absolute latitude and UV radiation levels. The highest correlation between skin reflectance and UV levels was observed at 545 nm, near the absorption maximum for oxyhemoglobin, suggesting that the main role of melanin pigmentation in humans is regulation of the effects of UV radiation on the contents of cutaneous blood vessels located in the dermis. (2) Predicted skin reflectances deviated little from observed values. (3) In all populations for which skin reflectance data were available for males and females, females were found to be lighter skinned than males. (4) The clinal gradation of skin coloration observed among indigenous peoples is correlated with UV radiation levels and represents a compromise solution to the conflicting physiological requirements of photoprotection and vitamin D synthesis. The earliest members of the hominid lineage probably had a mostly unpigmented or lightly pigmented integument covered with dark black hair, similar to that of the modern chimpanzee. The evolution of a naked, darkly pigmented integument occurred early in the evolution of the genus Homo. A dark epidermis protected sweat glands from UV-induced injury, thus insuring the integrity of somatic thermoregulation. Of greater significance to individual reproductive success was that highly melanized skin protected against UV-induced photolysis of

  12. 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. © 2012 John Wiley & Sons A/S.

  13. Familial occurrence of pigment dispersion syndrome.

    PubMed

    Bovell, A M; Damji, K F; Dohadwala, A A; Hodge, W G; Allingham, R R

    2001-02-01

    Pigment dispersion syndrome affects up to 4% of the white population. It is characterized by the presence of transillumination defects, Krukenberg's spindle and dense trabecular meshwork pigmentation. Open-angle glaucoma will develop in as many as 50% of affected patients. In this study we describe the familial occurrence of pigment dispersion syndrome in six North American pedigrees and the phenotypic characteristics with respect to pigment dispersion syndrome and glaucoma. Probands with pigment dispersion syndrome were identified in glaucoma clinics at university eye centres in Ottawa and Durham, NC. Families with two or more affected members were evaluated. All willing members in each family underwent a thorough clinical examination and were classified as affected with pigment dispersion syndrome, suspect or unaffected. The previous medical records were reviewed to obtain the past medical and ocular history, including risk factors for glaucoma. All six families are white. Three families show at least two generations of affected members. Of the 43 subjects examined 58% were women. All 14 affected members showed moderate to heavy trabecular meshwork pigmentation and either Krukenberg's spindle or transillumination defects. The affected members were also considerably more myopic (mean spherical equivalent for the right eye -4.72 dioptres) than the suspect group or the unaffected group (mean spherical equivalent -0.79 D and +1.19 D respectively) (p < or = 0.001), and the intraocular pressure was higher for the affected than the unaffected group (mean for the right eye 20 mm Hg vs. 16 mm Hg) (p = 0.004). Half of those affected also had open-angle glaucoma. We have identified and phenotypically characterized six North American families with autosomal dominant pigment dispersion syndrome. Our ultimate goal is to identify the gene(s) that causes this disorder in order to clarify its molecular etiology and pathophysiology. This may give rise to a molecular classification

  14. Beneficial Effects of Oral Supplementation With Ovoderm on Human Skin Physiology: Two Pilot Studies.

    PubMed

    Aguirre, Andrés; Gil-Quintana, Erena; Fenaux, Marisa; Erdozain, Sandra; Sarria, Itziar

    2017-11-02

    Collagens and hyaluronic acid have long been used in pharmaceuticals and food supplements for the improvement of skin elasticity and hydration. These compounds provide the building blocks of the skin. Ovoderm is an oral supplement obtained from eggshells that contains naturally occurring collagen and glycosaminoglycans, such as hyaluronic acid. We evaluated the efficacy of Ovoderm on skin biophysical parameters related to cutaneous aging such as elasticity, hydration, and pigmentation. Two pilot studies were run to assess the effect of daily oral supplementation with 300 mg Ovoderm on skin parameters. The first consisted of a self-assessment questionnaire intended to perform an assessment on skin, hair, and nail health after 50 days of treatment. The second measured the effect of 5-week treatment on hydration by corneometry, on elasticity with the cutometer, and on pigmentation with the mexameter. In the pilot study 1, participants were predominantly satisfied with the effects obtained on general face (100% volunteers satisfied) and body (94% volunteers satisfied) skin condition and skin properties (100% volunteers satisfied with facial skin softness, 94% with facial skin hydration, and 89% with body skin hydration) and partly with effects on hair (67% volunteers satisfied) and nail (50% volunteers satisfied) condition. The study 2 revealed a statistically significant improvement in skin elasticity (12% increase, p =.0136), a tendency to reduce skin pigmentation (5% decrease), and no significant change in skin hydration. Our study reflects that oral supplementation with Ovoderm is efficacious to reduce the gradual loss of skin elasticity characteristic of aged skin, which helps to improve the appearance of the skin.

  15. Neurologic abnormalities in murderers.

    PubMed

    Blake, P Y; Pincus, J H; Buckner, C

    1995-09-01

    Thirty-one individuals awaiting trial or sentencing for murder or undergoing an appeal process requested a neurologic examination through legal counsel. We attempted in each instance to obtain EEG, MRI or CT, and neuropsychological testing. Neurologic examination revealed evidence of "frontal" dysfunction in 20 (64.5%). There were symptoms or some other evidence of temporal lobe abnormality in nine (29%). We made a specific neurologic diagnosis in 20 individuals (64.5%), including borderline or full mental retardation (9) and cerebral palsy (2), among others. Neuropsychological testing revealed abnormalities in all subjects tested. There were EEG abnormalities in eight of the 20 subjects tested, consisting mainly of bilateral sharp waves with slowing. There were MRI or CT abnormalities in nine of the 19 subjects tested, consisting primarily of atrophy and white matter changes. Psychiatric diagnoses included paranoid schizophrenia (8), dissociative disorder (4), and depression (9). Virtually all subjects had paranoid ideas and misunderstood social situations. There was a documented history of profound, protracted physical abuse in 26 (83.8%) and of sexual abuse in 10 (32.3%). It is likely that prolonged, severe physical abuse, paranoia, and neurologic brain dysfunction interact to form the matrix of violent behavior.

  16. THE NATURE OF THE GECKO VISUAL PIGMENT

    PubMed Central

    Crescitelli, Frederick

    1956-01-01

    Retinal extracts of the Australian gecko, Phyllurus milii (White), have revealed the presence of a photosensitive pigment, unusual for terrestrial animals, because of its absorption maximum at 524 mµ. This pigment has an absorption spectrum which is identical in form with that of other visual chromoproteins. It is not a porphyropsin, for bleaching revealed the presence, not of retinene2, but of retinene1 as a chromophore. Photolabile pigments with characteristics similar to those of the Phyllurus visual pigment were also detected in retinal extracts of six other species of nocturnal geckos. The presence of this retinal chromoprotein adequately accounts for the unusual visual sensitivity curve described by Denton for the nocturnal gecko. This pigment may have special biological significance in terms of the unique phylogenetic position of geckos as living representatives of nocturnal animals which retain some of the characteristics of their diurnal ancestors. The occurrence of this retinene1 pigment, intermediate in spectral position between rhodopsin and iodopsin, is interpreted in support of the transmutation theory of Walls. The results and interpretation of this investigation point up the fact that, from a phylogenetic point of view, too great an emphasis on the duplicity theory may serve to detract attention from the evolutionary history of the retina and the essential unitarianism of the visual cells. PMID:13385449

  17. Immunoreactivities for glutathione S-transferases and glutathione peroxidase in the lateral wall of pigmented and albino guinea pig cochlea.

    PubMed

    Fujimura, Takeyuki; Suzuki, Hideaki; Udaka, Tsuyoshi; Shiomori, Teruo; Mori, Takanori; Inaba, Tsuyoshi; Hiraki, Nobuaki; Kayashima, Kotaro; Doi, Yoshiaki

    2008-09-01

    Dark-skinned people are known to be more tolerant of ototraumatic noise than are light-skinned people, and pigmented animals are more tolerant of ototraumatic noise and aminoglycoside ototoxicity than are albino animals. Such tolerance may be dependent on the local ability of detoxification and antioxidant enzymes, including glutathione S-transferase (GST) and glutathione peroxidase (GSPx). In the present study, we examined the difference in GST/GSPx expression in the lateral wall of the cochlea between pigmented and albino guinea pigs. Eight-week-old male pigmented and albino guinea pigs were killed by transcardiac perfusion with 2% paraformaldehyde. The cochlear ducts were isolated, further fixed with 4% paraformaldehyde, decalcified, and then embedded in paraffin. Sections prepared at 5-microm thickness were incubated with anti-GST-alpha,-mu,-pi, or anti-GSPx antibody, reacted with Alexa Fluorconjugated secondary antibody, and examined under a Carl Zeiss Axioskop 2 plus fluorescence microscope. The cochlea ducts were also subjected to immunoelectron microscopy for GST-pi by the postembedment method. The stria vascularis of pigmented guinea pigs was strongly immunoreactive for GST-alpha,-mu,-pi, and GSPx, whereas no or only weak immunoreactivities were seen in the stria vascularis of albino guinea pigs. The spiral ligament showed positive but different immunoreactivities for these enzymes between the strains. Double-stained immunofluorescence micrographs for GST-pi and GSPx showed a close resemblance of localization between the two enzymes in both pigmented and albino guinea pigs. At the ultrastructural level, immunoreactivity for GST-pi was localized preferentially in the melanin cells of pigmented guinea pigs. These results suggest that correlation between pigmentation and inner ear susceptibility is, at least partially, attributed to the different distribution of GST/GSPx in the stria vascularis.

  18. 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. © 2015 Wiley Periodicals, Inc.

  19. Identifying signatures of positive selection in pigmentation genes in two South Asian populations.

    PubMed

    Jonnalagadda, Manjari; Bharti, Neeraj; Patil, Yatish; Ozarkar, Shantanu; K, Sunitha Manjari; Joshi, Rajendra; Norton, Heather

    2017-09-10

    Skin pigmentation is a polygenic trait showing wide phenotypic variations among global populations. While numerous pigmentation genes have been identified to be under positive selection among European and East populations, genes contributing to phenotypic variation in skin pigmentation within and among South Asian populations are still poorly understood. The present study uses data from the Phase 3 of the 1000 genomes project focusing on two South Asian populations-GIH (Gujarati Indian from Houston, Texas) and ITU (Indian Telugu from UK), so as to decode the genetic architecture involved in adaptation to ultraviolet radiation in South Asian populations. Statistical tests included were (1) tests to identify deviations of the Site Frequency Spectrum (SFS) from neutral expectations (Tajima's D, Fay and Wu's H and Fu and Li's D* and F*), (2) tests focused on the identification of high-frequency haplotypes with extended linkage disequilibrium (iHS and Rsb), and (3) tests based on genetic differentiation between populations (LSBL). Twenty-two pigmentation genes fall in the top 1% for at least one statistic in the GIH population, 5 of which (LYST, OCA2, SLC24A5, SLC45A2, and TYR) have been previously associated with normal variation in skin, hair, or eye color. In comparison, 17 genes fall in the top 1% for at least one statistic in the ITU population. Twelve loci which are identified as outliers in the ITU scan were also identified in the GIH population. These results suggest that selection may have affected these loci broadly across the region. © 2017 Wiley Periodicals, Inc.

  20. Reconstitution of full‐thickness skin by microcolumn grafting

    PubMed Central

    Wang, Ying; Vuong, Linh N.; Fisher, Jeremy M.; Farinelli, William A.; Anderson, R. Rox

    2016-01-01

    Abstract In addition to providing a physical barrier, skin also serves a diverse range of physiological functions through different specialized resident cell types/structures, including melanocytes (pigmentation and protection against ultraviolet radiation), Langerhans cells (adaptive immunity), fibroblasts (maintaining extracellular matrix, paracrine regulation of keratinocytes), sweat glands (thermoregulation) and hair follicles (hair growth, sensation and a stem cell reservoir). Restoration of these functional elements has been a long‐standing challenge in efforts to engineer skin tissue, while autologous skin grafting is limited by the scarcity of donor site skin and morbidity caused by skin harvesting. We demonstrate an alternative approach of harvesting and then implanting μm‐scale, full‐thickness columns of human skin tissue, which can be removed from a donor site with minimal morbidity and no scarring. Fresh human skin microcolumns were used to reconstitute skin in wounds on immunodeficient mice. The restored skin recapitulated many key features of normal human skin tissue, including epidermal architecture, diverse skin cell populations, adnexal structures and sweat production in response to cholinergic stimulation. These promising preclinical results suggest that harvesting and grafting of microcolumns may be useful for reconstituting fully functional skin in human wounds, without donor site morbidity. © 2016 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons Ltd. PMID:27296503

  1. Reconstitution of full-thickness skin by microcolumn grafting.

    PubMed

    Tam, Joshua; Wang, Ying; Vuong, Linh N; Fisher, Jeremy M; Farinelli, William A; Anderson, R Rox

    2017-10-01

    In addition to providing a physical barrier, skin also serves a diverse range of physiological functions through different specialized resident cell types/structures, including melanocytes (pigmentation and protection against ultraviolet radiation), Langerhans cells (adaptive immunity), fibroblasts (maintaining extracellular matrix, paracrine regulation of keratinocytes), sweat glands (thermoregulation) and hair follicles (hair growth, sensation and a stem cell reservoir). Restoration of these functional elements has been a long-standing challenge in efforts to engineer skin tissue, while autologous skin grafting is limited by the scarcity of donor site skin and morbidity caused by skin harvesting. We demonstrate an alternative approach of harvesting and then implanting μm-scale, full-thickness columns of human skin tissue, which can be removed from a donor site with minimal morbidity and no scarring. Fresh human skin microcolumns were used to reconstitute skin in wounds on immunodeficient mice. The restored skin recapitulated many key features of normal human skin tissue, including epidermal architecture, diverse skin cell populations, adnexal structures and sweat production in response to cholinergic stimulation. These promising preclinical results suggest that harvesting and grafting of microcolumns may be useful for reconstituting fully functional skin in human wounds, without donor site morbidity. © 2016 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons Ltd. © 2016 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons Ltd.

  2. Black veins: a case of minocycline-induced pigmentation post-sclerotherapy and a review of literature.

    PubMed

    Star, Phoebe; Choy, Carolyn; Parsi, Kurosh

    2017-01-01

    Minocycline-induced pigmentation (MIP) is an uncommon but well-described adverse effect of oral minocycline treatment. MIP is clinically and histopathologically distinct from post-sclerotherapy pigmentation. We report a case of a patient presenting with blackened skin overlying veins recently treated with endovenous laser and foam sclerotherapy. The patient was a 44-year-old male with systemic sclerosis who commenced minocycline for the treatment of rosacea 5 months prior. Histological examination of the discolored tissue and underlying vein revealed hemosiderin deposition in the dermis and pigmented macrophages within the sub-endothelial layer of the vein wall with a staining pattern consistent with MIP. Venous tissue has not previously been reported in the literature as a target of minocycline pigmentation. Our patient preferred to control his rosacea by continuing to take minocycline. Follow-up ultrasound examinations revealed the treated vessels to be fully occluded with no evidence of recanalization, residual flow or ongoing thrombophlebitis. Despite a good sclerotherapy outcome, the pigmentation did not subside over 2 years. This case demonstrates that oral minocycline may induce significant and potentially long-term pigmentation in predisposed patients undergoing sclerotherapy. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. 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

  4. 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.

  5. [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.

  6. Quantitative assessment of skin, hair, and iris variation in a diverse sample of individuals and associated genetic variation.

    PubMed

    Norton, Heather L; Edwards, Melissa; Krithika, S; Johnson, Monique; Werren, Elizabeth A; Parra, Esteban J

    2016-08-01

    The main goals of this study are to 1) quantitatively measure skin, hair, and iris pigmentation in a diverse sample of individuals, 2) describe variation within and between these samples, and 3) demonstrate how quantitative measures can facilitate genotype-phenotype association tests. We quantitatively characterize skin, hair, and iris pigmentation using the Melanin (M) Index (skin) and CIELab values (hair) in 1,450 individuals who self-identify as African American, East Asian, European, Hispanic, or South Asian. We also quantify iris pigmentation in a subset of these individuals using CIELab values from high-resolution iris photographs. We compare mean skin M index and hair and iris CIELab values among populations using ANOVA and MANOVA respectively and test for genotype-phenotype associations in the European sample. All five populations are significantly different for skin (P <2 × 10(-16) ) and hair color (P <2 × 10(-16) ). Our quantitative analysis of iris and hair pigmentation reinforces the continuous, rather than discrete, nature of these traits. We confirm the association of three loci (rs16891982, rs12203592, and rs12913832) with skin pigmentation and four loci (rs12913832, rs12203592, rs12896399, and rs16891982) with hair pigmentation. Interestingly, the derived rs12203592 T allele located within the IRF4 gene is associated with lighter skin but darker hair color. The quantitative methods used here provide a fine-scale assessment of pigmentation phenotype and facilitate genotype-phenotype associations, even with relatively small sample sizes. This represents an important expansion of current investigations into pigmentation phenotype and associated genetic variation by including non-European and admixed populations. Am J Phys Anthropol 160:570-581, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  7. [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.

  8. 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.

  9. Berberine-induced pigment dispersion in Bufo melanostictus melanophores by stimulation of beta-2 adrenergic receptors.

    PubMed

    Ali, Sharique A; Naaz, Ishrat; Choudhary, Ram Kumar

    2014-02-01

    Reduced production of melanin by decreased or the absence of melanocytes leads to various hypopigmentation disorders, and the development of melanogenetic agents for photoprotection and hypopigmentation disorders is one of the top priority areas of research. Hence, the present study was carried out to elucidate the ability of berberine, a principal active ingredient present in the roots of the herb Berberis vulgaris to stimulate pigment dispersion in the isolated skin melanophores of the toad Bufo melanostictus. In the present study, mean melanophore size index of the isolated skin melanophores of B. melanostictus was assayed after treating with various concentrations of berberine. A marked melanin dispersion response leading to skin darkening was observed in the isolated melanophores of toad in response to berberine, which was found to be mediated through beta-2 adrenergic receptors. The physiologically significant dose-related melanin dispersion effects of berberine per se were found to be completely abolished by propranolol, which is a specific beta-2 adrenergic receptor blocker. These per se melanin dispersal effects were also found to be markedly potentiated by isoprenaline, which is a specific beta-adrenoceptor agonist. The results indicate that berberine causes a tremendous, dose-dependent, physiologically significant pigment dispersing in the isolated skin melanophores of B. melanostictus.

  10. Skin Cancer

    MedlinePlus

    ... early. Cancerous tissue can be removed with a minor surgical procedure. In many cases, that is all the treatment needed. Future lesions may occur. You will need to be vigilant about checking your skin and calling your doctor if you see changes. For more advanced cases, living with cancer during ...

  11. The colours of humanity: the evolution of pigmentation in the human lineage.

    PubMed

    Jablonski, Nina G; Chaplin, George

    2017-07-05

    Humans are a colourful species of primate, with human skin, hair and eye coloration having been influenced by a great variety of evolutionary forces throughout prehistory. Functionally naked skin has been the physical interface between the physical environment and the human body for most of the history of the genus Homo , and hence skin coloration has been under intense natural selection. From an original condition of protective, dark, eumelanin-enriched coloration in early tropical-dwelling Homo and Homo sapiens , loss of melanin pigmentation occurred under natural selection as Homo sapiens dispersed into non-tropical latitudes of Africa and Eurasia. Genes responsible for skin, hair and eye coloration appear to have been affected significantly by population bottlenecks in the course of Homo sapiens dispersals. Because specific skin colour phenotypes can be created by different combinations of skin colour-associated genetic markers, loss of genetic variability due to genetic drift appears to have had negligible effects on the highly redundant genetic 'palette' for the skin colour. This does not appear to have been the case for hair and eye coloration, however, and these traits appear to have been more strongly influenced by genetic drift and, possibly, sexual selection.This article is part of the themed issue 'Animal coloration: production, perception, function and application'. © 2017 The Author(s).

  12. Abnormality, rationality, and sanity.

    PubMed

    Hertwig, Ralph; Volz, Kirsten G

    2013-11-01

    A growing body of studies suggests that neurological and mental abnormalities foster conformity to norms of rationality that are widely endorsed in economics and psychology, whereas normality stands in the way of rationality thus defined. Here, we outline the main findings of these studies, discuss their implications for experimental design, and consider how 'sane' some benchmarks of rationality really are. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. The deceptive nature of UVA tanning versus the modest protective effects of UVB tanning on human skin.

    PubMed

    Miyamura, Yoshinori; Coelho, Sergio G; Schlenz, Kathrin; Batzer, Jan; Smuda, Christoph; Choi, Wonseon; Brenner, Michaela; Passeron, Thierry; Zhang, Guofeng; Kolbe, Ludger; Wolber, Rainer; Hearing, Vincent J

    2011-02-01

    The relationship between human skin pigmentation and protection from ultraviolet (UV) radiation is an important element underlying differences in skin carcinogenesis rates. The association between UV damage and the risk of skin cancer is clear, yet a strategic balance in exposure to UV needs to be met. Dark skin is protected from UV-induced DNA damage significantly more than light skin owing to the constitutively higher pigmentation, but an as yet unresolved and important question is what photoprotective benefit, if any, is afforded by facultative pigmentation (i.e. a tan induced by UV exposure). To address that and to compare the effects of various wavelengths of UV, we repetitively exposed human skin to suberythemal doses of UVA and/or UVB over 2 weeks after which a challenge dose of UVA and UVB was given. Although visual skin pigmentation (tanning) elicited by different UV exposure protocols was similar, the melanin content and UV-protective effects against DNA damage in UVB-tanned skin (but not in UVA-tanned skin) were significantly higher. UVA-induced tans seem to result from the photooxidation of existing melanin and its precursors with some redistribution of pigment granules, while UVB stimulates melanocytes to up-regulate melanin synthesis and increases pigmentation coverage, effects that are synergistically stimulated in UVA and UVB-exposed skin. Thus, UVA tanning contributes essentially no photoprotection, although all types of UV-induced tanning result in DNA and cellular damage, which can eventually lead to photocarcinogenesis. 2010 John Wiley & Sons A/S. This article is a US Government work and is in the public domain in the USA.

  14. Skin colour typology and suntanning pathways.

    PubMed

    Chardon, A; Cretois, I; Hourseau, C

    1991-08-01

    Synopsis The evaluation of sun-product efficacy, with laboratory solar simulators or in actual sun, implicates clinical and subjective assessment of the various skin responses in terms of wavelengths constitutive of solar light. These photobiological responses vary according to skin types and particularly to basic skin melanic content, i.e. with skin colour. Now, the instrumental measurement of live skin colour has become easier to perform, fast and reliable. Based on the standard CIE-L*a*b* colour system and correlated with the human eye, this technique was used to define the skin colour domain of the caucasian population, to propose a skin colour classification, and then to objectively follow, over a three week period, the dynamics and kinetics of tanning induced by UVB, UVA and UVB +/- A multi-exposures on the three skin categories. The specific directions in the three-dimensional L*a*b* colour space of the tanning components, i.e. erythema, immediate pigmentation and constitutional melanization, as well as the resulting tanning pathways, were analysed and defined in the three-dimensional colour space, using a vectorial method. The UVB, UVA and UVB +/- A tannings were differentiated by their intensity, their hue and especially their lasting capacity: UVA tanning clearly appeared more lasting than UVB. In addition, the UVA*UVB interaction on tanning intensity was not found to be significant. With the skin colour classification and the tanning models, this comprehensive study supplies a basic tool for the colorimetric interpretation of the skin phenomena involved, provided that this interpretation is always considered in the three dimensions of the colour space. It also suggests some useful practical applications for sun product formulation and evaluation.

  15. The fibroblast-derived paracrine factor neuregulin-1 has a novel role in regulating the constitutive color and melanocyte function in human skin

    PubMed Central

    Choi, Wonseon; Wolber, Rainer; Gerwat, Wolfram; Mann, Tobias; Batzer, Jan; Smuda, Christoph; Liu, Hongfang; Kolbe, Ludger; Hearing, Vincent J.

    2010-01-01

    Interactions between melanocytes and neighboring cells in the skin are important in regulating skin color in humans. We recently demonstrated that the less pigmented and thicker skin on the palms and soles is regulated by underlying fibroblasts in those areas, specifically via a secreted factor (DKK1) that modulates Wnt signaling. In this study, we tested the hypothesis that dermal fibroblasts regulate the constitutive skin color of individuals ranging from very light to very dark. We used microarray analysis to compare gene expression patterns in fibroblasts derived from lighter skin types compared to darker skin types, with a focus on secreted proteins. We identified a number of genes that differ dramatically in expression and, among the expressed proteins, neuregulin-1, which is secreted by fibroblasts derived from dark skin, effectively increases the pigmentation of melanocytes in tissue culture and in an artificial skin model and regulates their growth, suggesting that it is one of the major factors determining human skin color. PMID:20736300

  16. 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. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. 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

  18. Cushing syndrome in a young woman due to primary pigmented nodular adrenal disease.

    PubMed

    Hackman, Kathryn L; Davis, Anna L; Curnow, Paul A; Serpell, Jonathan W; McLean, Catriona A; Topliss, Duncan J

    2010-01-01

    To report a case of Cushing syndrome due to apparently sporadic primary pigmented nodular adrenal disease in a young woman. We describe the clinical, biochemical, radiologic, and histologic findings of Cushing syndrome due to the rare condition of primary pigmented nodular adrenal disease. A 30-year-old woman presented with a 2-year history of worsening itch without rash over her shoulders and arms and weight gain, particularly around the abdomen and face. Careful questioning did not elicit any history of exogenous glucocorticoid use (systemic or topical), including hydrocortisone. On examination, the patient had a slightly rounded and plethoric face, a small buffalo hump, central adiposity, and thin skin with a few small striae on her inner thighs. No features of the Carney complex were observed. Investigations showed hypercortisolism with suppressed corticotropin and normal adrenal imaging despite documentation of enlarged adrenal glands at removal. High-dose dexamethasone administration was followed by a decrease in urinary free cortisol excretion rather than a paradoxical rise as previously reported in primary pigmented nodular adrenal disease. No mutations were detected in the PRKAR1A gene. Primary pigmented nodular adrenal disease should be suspected in patients with corticotropin-independent Cushing syndrome who have normal adrenal imaging. The role of genetic testing in apparently sporadic cases is not established, but cumulative experience may be helpful in defining the frequency of PRKAR1A mutations.

  19. 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

  20. 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

  1. 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.

  2. Synchrotron powder diffraction on Aztec blue pigments

    NASA Astrophysics Data System (ADS)

    Sánchez Del Río, M.; Gutiérrez-León, A.; Castro, G. R.; Rubio-Zuazo, J.; Solís, C.; Sánchez-Hernández, R.; Robles-Camacho, J.; Rojas-Gaytán, J.

    2008-01-01

    Some samples of raw blue pigments coming from an archaeological rescue mission in downtown Mexico City have been characterized using different techniques. The samples, some recovered as a part of a ritual offering, could be assigned to the late Aztec period (XVth century). The striking characteristic of these samples is that they seem to be raw pigments prior to any use in artworks, and it was possible to collect a few μg of pigment after manual grain selection under a microscopy monitoring. All pigments are made of indigo, an organic colorant locally known as añil or xiuhquilitl. The colorant is always found in combination with an inorganic matrix, studied by powder diffraction. In one case the mineral base is palygorskite, a rare clay mineral featuring micro-channels in its structure, well known as the main ingredient of the Maya blue pigment. However, other samples present the minerals sepiolite (a clay mineral of the palygorskite family) and calcite. Another sample contains barite, a mineral never reported in prehispanic paints. We present the results of characterization using high resolution powder diffraction recorded at the European Synchrotron Radiation Facility (BM25A, SpLine beamline) complemented with other techniques. All of them gave consistent results on the composition. A chemical test on resistance to acids was done, showing a high resistance for the palygorskite and eventually sepiolite compounds, in good agreement with the excellent resistance of the Maya blue.

  3. Multiscale Pigment Analysis of Medieval Illuminated Manuscripts

    NASA Astrophysics Data System (ADS)

    Sestak, Erica; Manukyan, Khachatur; Wiescher, Michael; Gura, David

    2017-09-01

    Three medieval illuminated manuscripts (codd. Lat. b. 1; Lat. b. 2; Lat. e. 4), housed at the University of Notre Dame's Hesburgh Library, vary in style, pigments, scribes, and regions, despite all three being Psalters used in the Late Middle Ages. XRF and Raman spectroscopy, which provided the elemental and molecular composition of the pigments, respectively, were used to analyze the pigments' compositions in an attempt to narrow further the manuscripts' possible origins. This experimental investigation emphasizes the importance of understanding the history of the manuscript through their pigments. Codd. Lat. b. 1 and Lat. b. 2 are Latinate German Psalters from the fifteenth century likely used in Katharinenkloster in Nuremberg. While there are visible differences in style within each Psalter, the variations in some of the pigment compositions, such as the inconstant presence of zinc, suggest different admixtures. Cod. Lat. e. 4 is a Latinate English Psalter from the fourteenth century, and it was written by two scribes and illuminated by two distinct painters. It is currently being tested to determine whether there are any correlations between the scribes and painters. These physical analyses will clarify the origins and provenances of the manuscripts.

  4. 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.

  5. Skin lesion biopsy

    MedlinePlus

    ... biopsy - skin; Skin cancer - biopsy; Melanoma - biopsy; Squamous cell cancer - biopsy; Basal cell cancer - biopsy; Mohs microsurgery ... dermatitis Infection from bacteria or fungus Melanoma Basal cell skin cancer Squamous cell skin cancer

  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. Chimeric autologous/allogeneic constructs for skin regeneration.

    PubMed

    Rasmussen, Cathy Ann; Tam, Joshua; Steiglitz, Barry M; Bauer, Rebecca L; Peters, Noel R; Wang, Ying; Anderson, R Rox; Allen-Hoffmann, B Lynn

    2014-08-01

    The ideal treatment for severe cutaneous injuries would eliminate the need for autografts and promote fully functional, aesthetically pleasing autologous skin regeneration. NIKS progenitor cell-based skin tissues have been developed to promote healing by providing barrier function and delivering wound healing factors. Independently, a device has recently been created to "copy" skin by harvesting full-thickness microscopic tissue columns (MTCs) in lieu of autografts traditionally harvested as sheets. We evaluated the feasibility of combining these two technologies by embedding MTCs in NIKS-based skin tissues to generate chimeric autologous/allogeneic constructs. Chimeric constructs have the potential to provide immediate wound coverage, eliminate painful donor site wounds, and promote restoration of a pigmented skin tissue possessing hair follicles, sweat glands, and sebaceous glands. After MTC insertion, chimeric constructs and controls were reintroduced into air-interface culture and maintained in vitro for several weeks. Tissue viability, proliferative capacity, and morphology were evaluated after long-term culture. Our results confirmed successful MTC insertion and integration, and demonstrated the feasibility of generating chimeric autologous/allogeneic constructs that preserved the viability, proliferative capacity, and structure of autologous pigmented skin. These feasibility studies established the proof-of-principle necessary to further develop chimeric autologous/allogeneic constructs for the treatment of complex skin defects. Reprint & Copyright © 2014 Association of Military Surgeons of the U.S.

  8. Comparative Transcriptome Analysis Reveals the Genetic Basis of Skin Color Variation in Common Carp

    PubMed Central

    Jiang, Yanliang; Zhang, Songhao; Xu, Jian; Feng, Jianxin; Mahboob, Shahid; Al-Ghanim, Khalid A.; Sun, Xiaowen; Xu, Peng

    2014-01-01

    Background The common carp is an important aquaculture species that is widely distributed across the world. During the long history of carp domestication, numerous carp strains with diverse skin colors have been established. Skin color is used as a visual criterion to determine the market value of carp. However, the genetic basis of common carp skin color has not been extensively studied. Methodology/Principal Findings In this study, we performed Illumina sequencing on two common carp strains: the reddish Xingguo red carp and the brownish-black Yellow River carp. A total of 435,348,868 reads were generated, resulting in 198,781 assembled contigs that were used as reference sequences. Comparisons of skin transcriptome files revealed 2,012 unigenes with significantly different expression in the two common carp strains, including 874 genes that were up-regulated in Xingguo red carp and 1,138 genes that were up-regulated in Yellow River carp. The expression patterns of 20 randomly selected differentially expressed genes were validated using quantitative RT-PCR. Gene pathway analysis of the differentially expressed genes indicated that melanin biosynthesis, along with the Wnt and MAPK signaling pathways, is highly likely to affect the skin pigmentation process. Several key genes involved in the skin pigmentation process, including TYRP1, SILV, ASIP and xCT, showed significant differences in their expression patterns between the two strains. Conclusions In this study, we conducted a comparative transcriptome analysis of Xingguo red carp and Yellow River carp skins, and we detected key genes involved in the common carp skin pigmentation process. We propose that common carp skin pigmentation depends upon at least three pathways. Understanding fish skin color genetics will facilitate future molecular selection of the fish skin colors with high market values. PMID:25255374

  9. Comparative transcriptome analysis reveals the genetic basis of skin color variation in common carp.

    PubMed

    Jiang, Yanliang; Zhang, Songhao; Xu, Jian; Feng, Jianxin; Mahboob, Shahid; Al-Ghanim, Khalid A; Sun, Xiaowen; Xu, Peng

    2014-01-01

    The common carp is an important aquaculture species that is widely distributed across the world. During the long history of carp domestication, numerous carp strains with diverse skin colors have been established. Skin color is used as a visual criterion to determine the market value of carp. However, the genetic basis of common carp skin color has not been extensively studied. In this study, we performed Illumina sequencing on two common carp strains: the reddish Xingguo red carp and the brownish-black Yellow River carp. A total of 435,348,868 reads were generated, resulting in 198,781 assembled contigs that were used as reference sequences. Comparisons of skin transcriptome files revealed 2,012 unigenes with significantly different expression in the two common carp strains, including 874 genes that were up-regulated in Xingguo red carp and 1,138 genes that were up-regulated in Yellow River carp. The expression patterns of 20 randomly selected differentially expressed genes were validated using quantitative RT-PCR. Gene pathway analysis of the differentially expressed genes indicated that melanin biosynthesis, along with the Wnt and MAPK signaling pathways, is highly likely to affect the skin pigmentation process. Several key genes involved in the skin pigmentation process, including TYRP1, SILV, ASIP and xCT, showed significant differences in their expression patterns between the two strains. In this study, we conducted a comparative transcriptome analysis of Xingguo red carp and Yellow River carp skins, and we detected key genes involved in the common carp skin pigmentation process. We propose that common carp skin pigmentation depends upon at least three pathways. Understanding fish skin color genetics will facilitate future molecular selection of the fish skin colors with high market values.

  10. 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.

  11. 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

  12. 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.

  13. Corneal collagen crosslinking and pigment dispersion syndrome.

    PubMed

    LaHood, Benjamin R; Moore, Sacha

    2017-03-01

    We describe the case of a keratoconus patient with pigment dispersion syndrome (PDS) who was treated for progressive corneal ectasia with corneal collagen crosslinking (CXL). Pigment dispersion syndrome has been shown to have associated morphologic changes of the corneal endothelium. Corneal CXL has the potential to cause toxicity to the corneal endothelium, and adjacent pigment might increase the likelihood of damage. In this case, the presence of PDS had no detrimental effect on the outcome of treatment, and no complications were observed at 12 months follow-up, indicating that it may be safe to perform corneal CXL in the setting of PDS. This is an important observation as the number of indications for corneal CXL grows. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  14. Unraveling the chemical identity of meat pigments.

    PubMed

    Pegg, R B; Shahidi, F

    1997-10-01

    This review examines the chemistry of nitrite curing of meat and meat products as it relates to the development of cured meat color and provides a detailed account of how nitrite-free processed meats could be prepared using the preformed cooked cured-meat pigment (CCMP). Thus, a chemical description of meat color, both raw and cooked, and characterization of nitrosylheme pigments follows. Based on electron paramagnetic resonance (EPR), visible and infrared spectroscopic studies, evidence has been provided to support the hypothesis that the chemical structure of the preformed CCMP is identical to that of the pigment prepared in situ after thermal processing of nitrite-cured meat and is in fact a mononitrosylheme complex. An appendix, which describes the basic principles of EPR spectroscopy used in the context of this review, is attached.

  15. Mass Spectrometric Analysis of Synthetic Organic Pigments.

    PubMed

    Sugaya, Naeko; Takahashi, Mitsuko; Sakurai, Katsumi; Tanaka, Nobuko; Okubo, Ichiro; Kawakami, Tsuyoshi

    2018-04-18

    Though synthetic organic colorants are used in various applications nowadays, there is the concern that impurities by-produced during the manufacturing and degradation products in some of these colorants are persistent organic pollutants and carcinogens. Thus, it is important to identify the synthetic organic colorants in various products, such as commercial paints, ink, cosmetics, food, textile, and plastics. Dyes, which are soluble in water and other solvents, could be analyzed by chromatographic methods. In contrast, it is difficult to analyze synthetic organic pigments by these methods because of their insolubility. This review is an overview of mass spectrometric analysis of synthetic organic pigments by various ionization methods. We highlight a recent study of textile samples by atmospheric pressure solid analysis probe MS. Furthermore, the mass spectral features of synthetic organic pigments and their separation from other components such as paint media and plasticizers are discussed.

  16. 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.

  17. Retinal pigment epithelium changes in Kartagener syndrome.

    PubMed

    Garcia, Maria D; Ventura, Camila V; Dias, João R; Chang, Ta Chen P; Berrocal, Audina M

    2018-06-01

    We present the first case in the literature of a patient with Kartagener syndrome and ocular findings of nonexudative age-related macular degeneration. A 55-year-old woman with Kartagener syndrome and chronic angle closure glaucoma presented for evaluation of the retina. Optos ultra-widefield imaging of the fundus showed glaucomatous cupping, drusen, and retinal pigment epithelium changes within the macular region. Humphrey visual field testing confirmed glaucomatous changes. Drusenoid pigment epithelial detachments were observed bilaterally with optical coherence tomography. We hypothesize that in addition to the lungs, spermatozoa and the Fallopian tubes, the retinal pigment epithelium may also be affected by ciliary dysfunction in individuals with Kartagener syndrome. Given recent advances in our knowledge of retinal ciliopathies, further studies are needed to understand how ciliary dysfunction affects the retina in Kartagener syndrome.

  18. Abnormal Uterine Bleeding.

    PubMed

    Benetti-Pinto, Cristina Laguna; Rosa-E-Silva, Ana Carolina Japur de Sá; Yela, Daniela Angerame; Soares Júnior, José Maria

    2017-07-01

    Abnormal uterine bleeding is a frequent condition in Gynecology. It may impact physical, emotional sexual and professional aspects of the lives of women, impairing their quality of life. In cases of acute and severe bleeding, women may need urgent treatment with volumetric replacement and prescription of hemostatic substances. In some specific cases with more intense and prolonged bleeding, surgical treatment may be necessary. The objective of this chapter is to describe the main evidence on the treatment of women with abnormal uterine bleeding, both acute and chronic. Didactically, the treatment options were based on the current International Federation of Gynecology and Obstetrics (FIGO) classification system (PALM-COEIN). The etiologies of PALM-COEIN are: uterine Polyp (P), Adenomyosis (A), Leiomyoma (L), precursor and Malignant lesions of the uterine body (M), Coagulopathies (C), Ovulatory dysfunction (O), Endometrial dysfunction (E), Iatrogenic (I), and Not yet classified (N). The articles were selected according to the recommendation grades of the PubMed, Cochrane and Embase databases, and those in which the main objective was the reduction of uterine menstrual bleeding were included. Only studies written in English were included. All editorial or complete papers that were not consistent with abnormal uterine bleeding, or studies in animal models, were excluded. The main objective of the treatment is the reduction of menstrual flow and morbidity and the improvement of quality of life. It is important to emphasize that the treatment in the acute phase aims to hemodynamically stabilize the patient and stop excessive bleeding, while the treatment in the chronic phase is based on correcting menstrual dysfunction according to its etiology and clinical manifestations. The treatment may be surgical or pharmacological, and the latter is based mainly on hormonal therapy, anti-inflammatory drugs and antifibrinolytics. Thieme Revinter Publicações Ltda Rio de Janeiro

  19. Next generation human skin constructs as advanced tools for drug development.

    PubMed

    Abaci, H E; Guo, Zongyou; Doucet, Yanne; Jacków, Joanna; Christiano, Angela

    2017-11-01

    Many diseases, as well as side effects of drugs, manifest themselves through skin symptoms. Skin is a complex tissue that hosts various specialized cell types and performs many roles including physical barrier, immune and sensory functions. Therefore, modeling skin in vitro presents technical challenges for tissue engineering. Since the first attempts at engineering human epidermis in 1970s, there has been a growing interest in generating full-thickness skin constructs mimicking physiological functions by incorporating various skin components, such as vasculature and melanocytes for pigmentation. Development of biomimetic in vitro human skin models with these physiological functions provides a new tool for drug discovery, disease modeling, regenerative medicine and basic research for skin biology. This goal, however, has long been delayed by the limited availability of different cell types, the challenges in establishing co-culture conditions, and the ability to recapitulate the 3D anatomy of the skin. Recent breakthroughs in induced pluripotent stem cell (iPSC) technology and microfabrication techniques such as 3D-printing have allowed for building more reliable and complex in vitro skin models for pharmaceutical screening. In this review, we focus on the current developments and prevailing challenges in generating skin constructs with vasculature, skin appendages such as hair follicles, pigmentation, immune response, innervation, and hypodermis. Furthermore, we discuss the promising advances that iPSC technology offers in order to generate in vitro models of genetic skin diseases, such as epidermolysis bullosa and psoriasis. We also discuss how future integration of the next generation human skin constructs onto microfluidic platforms along with other tissues could revolutionize the early stages of drug development by creating reliable evaluation of patient-specific effects of pharmaceutical agents. Impact statement Skin is a complex tissue that hosts various

  20. Data based abnormality detection

    NASA Astrophysics Data System (ADS)

    Purwar, Yashasvi

    Data based abnormality detection is a growing research field focussed on extracting information from feature rich data. They are considered to be non-intrusive and non-destructive in nature which gives them a clear advantage over conventional methods. In this study, we explore different streams of data based anomalies detection. We propose extension and revisions to existing valve stiction detection algorithm supported with industrial case study. We also explored the area of image analysis and proposed a complete solution for Malaria diagnosis. The proposed method is tested over images provided by pathology laboratory at Alberta Health Service. We also address the robustness and practicality of the solution proposed.

  1. 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. © 2015 The Fisheries Society of the British Isles.

  2. 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 ...

  3. Chemical peeling in ethnic skin: an update.

    PubMed

    Salam, A; Dadzie, O E; Galadari, H

    2013-10-01

    With the growth of cosmetic dermatology worldwide, treatments that are effective against skin diseases and augment beauty without prolonged recovery periods, or exposing patients to the risks of surgery, are increasing in popularity. Chemical peels are a commonly used, fast, safe and effective clinic room treatment that may be used for cosmetic purposes, such as for fine lines and photoageing, but also as primary or adjunct therapies for acne, pigmentary disorders and scarring. Clinicians are faced with specific challenges when using peels on ethnic skin (skin of colour). The higher risk of postinflammatory dyschromias and abnormal scarring makes peels potentially disfiguring. Clinicians should therefore have a sound knowledge of the various peels available and their safety in ethnic skin. This article aims to review the background, classification, various preparations, indications, patient assessment and complications of using chemical peels in ethnic skin. © 2013 The Authors BJD © 2013 British Association of Dermatologists.

  4. Green pigments of the Pompeian artists' palette.

    PubMed

    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.

  5. 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.

  6. Pigmentation, anesthesia, behavioral factors, and salicylate uptake.

    PubMed

    Jastreboff, P J; Issing, W; Brennan, J F; Sasaki, C T

    1988-02-01

    In four experiments, 54 pigmented rats were used to examine the time course of sodium salicylate uptake in serum, cerebrospinal fluid, and perilymph. Subjects were tested under sodium pentobarbital anesthesia or while conscious. Compared with previously reported data from albino rats, pigmented subjects generally showed increased salicylate uptake. Moreover, the data suggested two different, time-dependent clearance mechanisms in conscious animals not observed in anesthetized rats. Daily injections of salicylate did not produce an accumulation of salicylate in serum. Systematically higher levels of salicylate were observed in perilymph compared with cerebrospinal fluid. Behavioral procedures, including water deprivation and conditioned suppression of ongoing drinking levels, had no effect on salicylate levels.

  7. 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.

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

    PubMed

    Mujahid, Nisma; Liang, Yanke; Murakami, Ryo; Choi, Hwan Geun; Dobry, Allison S; Wang, Jinhua; Suita, Yusuke; Weng, Qing Yu; Allouche, Jennifer; Kemeny, Lajos V; Hermann, Andrea L; Roider, Elisabeth M; Gray, Nathanael S; Fisher, David E

    2017-06-13

    The presence of dark melanin (eumelanin) within human epidermis represents one of the strongest predictors of low skin cancer risk. Topical rescue of eumelanin synthesis, previously achieved in "redhaired" Mc1r-deficient mice, demonstrated significant protection against UV damage. However, application of a topical strategy for human skin pigmentation has not been achieved, largely due to the greater barrier function of human epidermis. Salt-inducible kinase (SIK) has been demonstrated to regulate MITF, the master regulator of pigment gene expression, through its effects on CRTC and CREB activity. Here, we describe the development of small-molecule SIK inhibitors that were optimized for human skin penetration, resulting in MITF upregulation and induction of melanogenesis. When topically applied, pigment production was induced in Mc1r-deficient mice and normal human skin. These findings demonstrate a realistic pathway toward UV-independent topical modulation of human skin pigmentation, potentially impacting UV protection and skin cancer risk. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  9. Tight Junction Protein 1a regulates pigment cell organisation during zebrafish colour patterning.

    PubMed

    Fadeev, Andrey; Krauss, Jana; Frohnhöfer, Hans Georg; Irion, Uwe; Nüsslein-Volhard, Christiane

    2015-04-27

    Zebrafish display a prominent pattern of alternating dark and light stripes generated by the precise positioning of pigment cells in the skin. This arrangement is the result of coordinated cell movements, cell shape changes, and the organisation of pigment cells during metamorphosis. Iridophores play a crucial part in this process by switching between the dense form of the light stripes and the loose form of the dark stripes. Adult schachbrett (sbr) mutants exhibit delayed changes in iridophore shape and organisation caused by truncations in Tight Junction Protein 1a (ZO-1a). In sbr mutants, the dark stripes are interrupted by dense iridophores invading as coherent sheets. Immuno-labelling and chimeric analyses indicate that Tjp1a is expressed in dense iridophores but down-regulated in the loose form. Tjp1a is a novel regulator of cell shape changes during colour pattern formation and the first cytoplasmic protein implicated in this process.

  10. 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.

  11. Skin findings in Williams syndrome.

    PubMed

    Kozel, Beth A; Bayliss, Susan J; Berk, David R; Waxler, Jessica L; Knutsen, Russell H; Danback, Joshua R; Pober, Barbara R

    2014-09-01

    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. © 2014 Wiley Periodicals, Inc.

  12. 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

  13. Separation of Chloroplast Pigments Using Reverse Phase Chromatography.

    ERIC Educational Resources Information Center

    Reese, R. Neil

    1997-01-01

    Presents a protocol that uses reverse phase chromatography for the separation of chloroplast pigments. Provides a simple and relatively safe procedure for use in teaching laboratories. Discusses pigment extraction, chromatography, results, and advantages of the process. (JRH)

  14. Skin transcriptome profiles associated with coat color in sheep

    PubMed Central

    2013-01-01

    Background Previous molecular genetic studies of physiology and pigmentation of sheep skin have focused primarily on a limited number of genes and proteins. To identify additional genes that may play important roles in coat color regulation, Illumina sequencing technology was used to catalog global gene expression profiles in skin of sheep with white versus black coat color. Results There were 90,006 and 74,533 unigenes assembled from the reads obtained from white and black sheep skin, respectively. Genes encoding for the ribosomal proteins and keratin associated proteins were most highly expressed. A total of 2,235 known genes were differentially expressed in black versus white sheep skin, with 479 genes up-regulated and 1,756 genes down-regulated. A total of 845 novel genes were differentially expressed in black versus white sheep skin, consisting of 107 genes which were up-regulated (including 2 highly expressed genes exclusively expressed in black sheep skin) and 738 genes that were down-regulated. There was also a total of 49 known coat color genes expressed in sheep skin, from which 13 genes showed higher expression in black sheep skin. Many of these up-regulated genes, such as DCT, MATP, TYR and TYRP1, are members of the components of melanosomes and their precursor ontology category. Conclusion The white and black sheep skin transcriptome profiles obtained provide a valuable resource for future research to understand the network of gene expression controlling skin physiology and melanogenesis in sheep. PMID:23758853

  15. TPC2 controls pigmentation by regulating melanosome pH and size

    PubMed Central

    Ambrosio, Andrea L.; Boyle, Judith A.; Aradi, Al E.; Christian, Keith A.; Di Pietro, Santiago M.

    2016-01-01

    Melanin is responsible for pigmentation of skin and hair and is synthesized in a specialized organelle, the melanosome, in melanocytes. A genome-wide association study revealed that the two pore segment channel 2 (TPCN2) gene is strongly linked to pigmentation variations. TPCN2 encodes the two-pore channel 2 (TPC2) protein, a cation channel. Nevertheless, how TPC2 regulates pigmentation remains unknown. Here, we show that TPC2 is expressed in melanocytes and localizes to the melanosome-limiting membrane and, to a lesser extent, to endolysosomal compartments by confocal fluorescence and immunogold electron microscopy. Immunomagnetic isolation of TPC2-containing organelles confirmed its coresidence with melanosomal markers. TPCN2 knockout by means of clustered regularly interspaced short palindromic repeat/CRISPR-associated 9 gene editing elicited a dramatic increase in pigment content in MNT-1 melanocytic cells. This effect was rescued by transient expression of TPC2-GFP. Consistently, siRNA-mediated knockdown of TPC2 also caused a substantial increase in melanin content in both MNT-1 cells and primary human melanocytes. Using a newly developed genetically encoded pH sensor targeted to melanosomes, we determined that the melanosome lumen in TPC2-KO MNT-1 cells and primary melanocytes subjected to TPC2 knockdown is less acidic than in control cells. Fluorescence and electron microscopy analysis revealed that TPC2-KO MNT-1 cells have significantly larger melanosomes than control cells, but the number of organelles is unchanged. TPC2 likely regulates melanosomes pH and size by mediating Ca2+ release from the organelle, which is decreased in TPC2-KO MNT-1 cells, as determined with the Ca2+ sensor tyrosinase-GCaMP6. Thus, our data show that TPC2 regulates pigmentation through two fundamental determinants of melanosome function: pH and size. PMID:27140606

  16. TPC2 controls pigmentation by regulating melanosome pH and size.

    PubMed

    Ambrosio, Andrea L; Boyle, Judith A; Aradi, Al E; Christian, Keith A; Di Pietro, Santiago M

    2016-05-17

    Melanin is responsible for pigmentation of skin and hair and is synthesized in a specialized organelle, the melanosome, in melanocytes. A genome-wide association study revealed that the two pore segment channel 2 (TPCN2) gene is strongly linked to pigmentation variations. TPCN2 encodes the two-pore channel 2 (TPC2) protein, a cation channel. Nevertheless, how TPC2 regulates pigmentation remains unknown. Here, we show that TPC2 is expressed in melanocytes and localizes to the melanosome-limiting membrane and, to a lesser extent, to endolysosomal compartments by confocal fluorescence and immunogold electron microscopy. Immunomagnetic isolation of TPC2-containing organelles confirmed its coresidence with melanosomal markers. TPCN2 knockout by means of clustered regularly interspaced short palindromic repeat/CRISPR-associated 9 gene editing elicited a dramatic increase in pigment content in MNT-1 melanocytic cells. This effect was rescued by transient expression of TPC2-GFP. Consistently, siRNA-mediated knockdown of TPC2 also caused a substantial increase in melanin content in both MNT-1 cells and primary human melanocytes. Using a newly developed genetically encoded pH sensor targeted to melanosomes, we determined that the melanosome lumen in TPC2-KO MNT-1 cells and primary melanocytes subjected to TPC2 knockdown is less acidic than in control cells. Fluorescence and electron microscopy analysis revealed that TPC2-KO MNT-1 cells have significantly larger melanosomes than control cells, but the number of organelles is unchanged. TPC2 likely regulates melanosomes pH and size by mediating Ca(2+) release from the organelle, which is decreased in TPC2-KO MNT-1 cells, as determined with the Ca(2+) sensor tyrosinase-GCaMP6. Thus, our data show that TPC2 regulates pigmentation through two fundamental determinants of melanosome function: pH and size.

  17. Color Change After Paramedical Pigmentation of the Nipple-Areola Complex.

    PubMed

    Tomita, Shoichi; Mori, Katsuya; Miyawaki, Takeshi

    2018-06-01

    Reconstruction of the nipple-areola complex is the final process in breast reconstruction. Local flaps and paramedical pigmentation is one of the major procedures for this. However, fading after paramedical pigmentation leads to a color difference between the selected pigment and its color in the skin. The aim of this study is to make a proposition in color choice of paramedical pigmentation for nipple-areola complex. Our research focused on investigating the color changes over time after unilateral nipple-areola complex reconstruction using paramedical pigmentation in 25 patients to propose suitable color selections. We measured the color by spectrometer and conducted comparisons using the hue, saturation, and value (HSV) color space and the color space defined by the Commission International de L'eclairage based on one channel for luminance (lightness) (L) and two color channels (a and b) (L*a*b*). A comparison of the hue, value, and saturation of the reconstructed areola compared to the normal areolae was conducted using HSV color space; the value and saturation were satisfactory after 3 months and beyond, but the reconstructed areola tended to have stronger red hues. The color difference (ΔE 00 ) calculated in L*a*b* color space showed slow fading after the scab was peeled off. This result indicates that a color with less redness and more yellowness, particularly 4-5 degrees of yellowness on the color wheel, than the normal side is the most appropriate color selection for this technique. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

  18. Hyperspectral remote sensing of plant pigments.

    PubMed

    Blackburn, George Alan

    2007-01-01

    The dynamics of pigment concentrations are diagnostic of a range of plant physiological properties and processes. This paper appraises the developing technologies and analytical methods for quantifying pigments non-destructively and repeatedly across a range of spatial scales using hyperspectral remote sensing. Progress in deriving predictive relationships between various characteristics and transforms of hyperspectral reflectance data are evaluated and the roles of leaf and canopy radiative transfer models are reviewed. Requirements are identified for more extensive intercomparisons of different approaches and for further work on the strategies for interpreting canopy scale data. The paper examines the prospects for extending research to the wider range of pigments in addition to chlorophyll, testing emerging methods of hyperspectral analysis and exploring the fusion of hyperspectral and LIDAR remote sensing. In spite of these opportunities for further development and the refinement of techniques, current evidence of an expanding range of applications in the ecophysiological, environmental, agricultural, and forestry sciences highlights the growing value of hyperspectral remote sensing of plant pigments.

  19. Pigment dispersion syndrome: a clinical study.

    PubMed Central

    Scheie, H G; Cameron, J D

    1981-01-01

    This study involved a group of 407 patients (799 eyes) with pigment dispersion syndrome gathered from a glaucoma population of 9200 patients. The sex distribution was equal. The majority (65%) of patients were myopic. The incidence of retinal detachment was 6.4%. No patients were black, but 5 were mulatto. Approximately one-quarter of the patients wih pigment dispersion syndrome (31% of the men, 19% of the women) had glaucoma. The average age of onset of glaucoma was 15 years less than in control patients with chronic simple glaucoma. When both eyes were affected by glaucoma, the glaucoma was consistently more severe in the eye with the more heavily pigmented angle. The degree of iris transillumination was found to be of no importance in predicting the presence of glaucoma or the severity of trabecular pigmentation. The pressure in 66% of the eyes with pigmentary glaucoma was controlled medically. A higher percentage of patients with pigmentary glaucoma required surgery than patients in the control group with chronic simple glaucoma. Men with pigmentary glaucoma required surgery at a much earlier age than women with pigmentary glaucoma. PMID:7236571

  20. Retinal pigment epithelial dystrophy in Briard dogs.

    PubMed

    Lightfoot, R M; Cabral, L; Gooch, L; Bedford, P G; Boulton, M E

    1996-01-01

    The eyes of normal Briard dogs, Briards affected with inherited retinal pigment epithelial dystrophy (RPED) and a range of normal crossbred and beagle dogs were examined and the histopathology of RPED in the Briard was compared with the histopathological features of ageing in the normal canine retina. RPED was characterised by the accumulation of auto-fluorescent lipofuscin-like inclusions in the retinal pigment epithelium (RPE), which initially involved only non-pigmented RPE cells overlying the tapetum but subsequently spread to all pigmented RPE cells. Secondary neuro-retinal degeneration was characterised by a gradual loss of the outer nuclear layer and the subsequent atrophy and degeneration of the inner retina. The loss of primary photoreceptors in the peripheral retina was accompanied by the migration of photoreceptor nuclei and appeared to resemble severe changes due to ageing. Intra-vitreal radiolabelled leucine was used to examine the rate of turnover of the outer segments of the rods in some Briards, but no significant variations were found. The activity of acid phosphatase in RPE was assayed in vitro and showed comparable regional variations in Briard and crossbred dogs. The results suggest that RPED in the Briard is unlikely to be due either to an increased rate of turnover of rod outer segments (and thus an increased phagocytic load) or to a primary insufficiency of lysosomal enzyme.

  1. "Dry-column" chromatography of plant pigments

    NASA Technical Reports Server (NTRS)

    Woeller, F. H.; Lehwalt, M. F.; Oyama, V. I.

    1973-01-01

    Separation of plant pigments which can be accomplished on thin-layer silica plates with mixture of petroleum ether, halocarbon, acetone, and polar solvent can be readily translated into dry-column technique that yields reproducible chromatograms after elution in fashion of liquid chromatography with fluorimeter as detector. Best solvent system was found to be mixture of petroleum ether, dichloromethane, acetone, and ethyl acetate.

  2. Ictal Cardiac Ryhthym Abnormalities.

    PubMed

    Ali, Rushna

    2016-01-01

    Cardiac rhythm abnormalities in the context of epilepsy are a well-known phenomenon. However, they are under-recognized and often missed. The pathophysiology of these events is unclear. Bradycardia and asystole are preceded by seizure onset suggesting ictal propagation into the cortex impacting cardiac autonomic function, and the insula and amygdala being possible culprits. Sudden unexpected death in epilepsy (SUDEP) refers to the unanticipated death of a patient with epilepsy not related to status epilepticus, trauma, drowning, or suicide. Frequent refractory generalized tonic-clonic seizures, anti-epileptic polytherapy, and prolonged duration of epilepsy are some of the commonly identified risk factors for SUDEP. However, the most consistent risk factor out of these is an increased frequency of generalized tonic-clonic seizures (GTC). Prevention of SUDEP is extremely important in patients with chronic, generalized epilepsy. Since increased frequency of GTCS is the most consistently reported risk factor for SUDEP, effective seizure control is the most important preventive strategy.

  3. 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.

  4. 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. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Defective pigment granule biogenesis and aberrant behavior caused by mutations in the Drosophila AP-3beta adaptin gene ruby.

    PubMed Central

    Kretzschmar, D; Poeck, B; Roth, H; Ernst, R; Keller, A; Porsch, M; Strauss, R; Pflugfelder, G O

    2000-01-01

    Lysosomal protein trafficking is a fundamental process conserved from yeast to humans. This conservation extends to lysosome-like organelles such as mammalian melanosomes and insect eye pigment granules. Recently, eye and coat color mutations in mouse (mocha and pearl) and Drosophila (garnet and carmine) were shown to affect subunits of the heterotetrameric adaptor protein complex AP-3 involved in vesicle trafficking. Here we demonstrate that the Drosophila eye color mutant ruby is defective in the AP-3beta subunit gene. ruby expression was found in retinal pigment and photoreceptor cells and in the developing central nervous system. ruby mutations lead to a decreased number and altered size of pigment granules in various cell types in and adjacent to the retina. Humans with lesions in the related AP-3betaA gene suffer from Hermansky-Pudlak syndrome, which is caused by defects in a number of lysosome-related organelles. Hermansky-Pudlak patients have a reduced skin pigmentation and suffer from internal bleeding, pulmonary fibrosis, and visual system malfunction. The Drosophila AP-3beta adaptin also appears to be involved in processes other than eye pigment granule biogenesis because all ruby allele combinations tested exhibited defective behavior in a visual fixation paradigm. PMID:10790396

  6. Properties of wine polymeric pigments formed from anthocyanin and tannins differing in size distribution and subunit composition.

    PubMed

    Bindon, Keren; Kassara, Stella; Hayasaka, Yoji; Schulkin, Alex; Smith, Paul

    2014-11-26

    To explore the effect of tannin composition on pigment formation, model ferments of purified 3-O-monoglucoside anthocyanins (ACN) were conducted either alone or in the presence of two different tannins. Tannins were isolated from grape seeds (Sd) or skins (Sk) following exhaustive extraction in 70% v/v acetone. The Sd and Sk tannin fractions had a mean degree of polymerization of 5.2 and 25.6, respectively. The Sd fraction was highly galloylated, at 22%, but galloylation was <2% in the Sk fraction. The Sk fraction was distinguished by a high proportion of prodelphinidin, at 58%. After a 6 month aging period, polymeric pigments were quantified and their color properties determined following isolation by solid-phase extraction. Wine color and polymeric pigment were highest in the treatment containing ACN+Sd and similar in the ACN+Sk and ACN treatments. The same trend between treatments was observed for total and polymeric nonbleachable pigments. Only minor changes in tannin subunit composition were found following ACN incorporation, but the size distribution of polymeric pigments determined by gel permeation chromatography decreased, in particular for the ACN+Sk treatment. Color incorporation in the higher molecular mass range was lower for ACN+Sk wines than for ACN+Sd wines. Compositional differences between the two tannin fractions may therefore limit the incorporation of ACNs in the colored form. The results suggest that in the ACN+Sk and ACN treatments, the formation of lower molecular mass oligomeric pigments was favored. In polymeric pigments derived from ACNs, the presence of ethyl- and vinyl-linked ACNs to the level of trimers was identified using mass spectrometry.

  7. Organ culture of mammalian skin and the effects of ultraviolet light and testosterone on melanocyte morphology and function

    SciTech Connect

    Glimcher, M.E.; Garcia, R.I.; Szab'o, G.

    1978-05-01

    Scrotal skin of black Long-Evans rats and human thigh skin were maintained in vitro as organ cultures for as long as 14 days, and examined histologically using the combined skin splitting and Dopa techniques. Selected rat skin cultures received testosterone in the culture medium and/or were irradiated with ultraviolet light (290 to 320 nm uvl). With increased time in culture, scrotal melanocytes round up and there is an increase in epidermal pigmentation. Human skin behaves similarly; after eight days in vitro human melanocytes also become rounded, but remain strongly Dopa-positive. Addition of exogenous testosterone to cultured rat skin maintains dendriticmore » morphology of melanocytes, but cell body size is still reduced. uvl irradiation stimulates melanocytes in rat skin cultures, maintaining their dendritic morphology and increasing epidermal and dermal pigmentation. Cultured skin receiving both uvl and testosterone illustrates a synergistic effect. Electron microscopic examination of cultured rat skin shows the presence of large melanosome complexes in keratinocytes, much larger than those found in vivo. Melanocytes appear to be active as they contain an extensive Golgi zone, rough endoplasmic reticulum, and melanosomes in various stages of formation. Dermis contained many dermal melanocytes and macrophages laden with melanosomes, correlating with the increased visible dermal pigmentation in vitro. This uvl stimulation of melanocytes in our skin organ cultures contrasts with the lack of melanogenic stimulation found in melanoma cell cultures. Our findings suggest that the intact epidermal melanin unit may be necessary for uvl stimulation of melanocytes.« less

  8. Abnormal mitochondrial respiration in failed human myocardium.

    PubMed

    Sharov, V G; Todor, A V; Silverman, N; Goldstein, S; Sabbah, H N

    2000-12-01

    Chronic heart failure (HF) is associated with morphologic abnormalities of cardiac mitochondria including hyperplasia, reduced organelle size and compromised structural integrity. In this study, we examined whether functional abnormalities of mitochondrial respiration are also present in myocardium of patients with advanced HF. Mitochondrial respiration was examined using a Clark electrode in an oxygraph cell containing saponin-skinned muscle bundles obtained from myocardium of failed explanted human hearts due to ischemic (ICM, n=9) or idiopathic dilated (IDC, n=9) cardiomyopathy. Myocardial specimens from five normal donor hearts served as controls (CON). Basal respiratory rate, respiratory rate after addition of the substrates glutamate and malate (V(SUB)), state 3 respiration (after addition of ADP, V(ADP)) and respiration after the addition of atractyloside (V(AT)) were measured in scar-free muscle bundles obtained from the subendocardial (ENDO) and subepicardial (EPI) thirds of the left ventricular (LV) free wall, interventricular septum and right ventricular (RV) free wall. There were no differences in basal and substrate-supported respiration between CON and HF regardless of etiology. V(ADP)was significantly depressed both in ICM and IDC compared to CON in all the regions studied. The respiratory control ratio, V(ADP)/V(AT), was also significantly decreased in HF compared to CON. In both ICM and IDC, V(ADP)was significantly lower in ENDO compared to EPI. The results indicate that mitochondrial respiration is abnormal in the failing human heart. The findings support the concept of low myocardial energy production in HF via oxidative phosphorylation, an abnormality with a potentially impact on global cardiac performance. Copyright 2000 Academic Press.

  9. Effect of pigment concentration on fastness and color values of thermal and UV curable pigment printing

    NASA Astrophysics Data System (ADS)

    Baysal, Gulcin; Kalav, Berdan; Karagüzel Kayaoğlu, Burçak

    2017-10-01

    In the current study, it is aimed to determine the effect of pigment concentration on fastness and colour values of thermal and ultraviolet (UV) curable pigment printing on synthetic leather. For this purpose, thermal curable solvent-based and UV curable water-based formulations were prepared with different pigment concentrations (3, 5 and 7%) separately and applied by screen printing technique using a screen printing machine. Samples printed with solvent-based formulations were thermally cured and samples printed with water-based formulations were cured using a UV curing machine equipped with gallium and mercury (Ga/Hg) lamps at room temperature. The crock fastness values of samples printed with solvent-based formulations showed that increase in pigment concentration was not effective on both dry and wet crock fastness values. On the other hand, in samples printed with UV curable water-based formulations, dry crock fastness was improved and evaluated as very good for all pigment concentrations. However, increasing the pigment concentration affected the wet crock fastness values adversely and lower values were observed. As the energy level increased for each irradiation source, the fastness values were improved. In comparison with samples printed with solvent-based formulations, samples printed with UV curable water-based formulations yielded higher K/S values at all pigment concentrations. The results suggested that, higher K/S values can be obtained in samples printed with UV curable water-based formulations at a lower pigment concentration compared to samples printed with solvent-based formulations.

  10. The concave iris in pigment dispersion syndrome.

    PubMed

    Liu, Lance; Ong, Ee Lin; Crowston, Jonathan

    2011-01-01

    To visualize the changes of the iris contour in patients with pigment dispersion syndrome after blinking, accommodation, and pharmacologic miosis using anterior segment optical coherence tomography. Observational case series. A total of 33 eyes of 20 patients with pigment dispersion syndrome. Each eye was imaged along the horizontal 0- to 180-degree meridian using the Visante Anterior Segment Imaging System (Carl Zeiss Meditec, Dublin, CA). Scans were performed at baseline and after focusing on an internal fixation target for 5 minutes, forced blinking, accommodation, and pharmacologic miosis with pilocarpine 2%. Quantitative analysis of the changes in the iris configuration. After 5 minutes of continual fixation, the iris became planar with the mean ± standard deviation curvature decreasing from 214 ± 74 μm to 67 ± 76 μm (P < 0.05). The iris remained planar in all patients with pigment dispersion syndrome after forced blinking, but the iris concavity recovered to 227 ± 113 μm (P = 0.34) and 238 ± 119 μm (P = 0.19) with the -3.0 and -6.0 diopter lenses, respectively. Pilocarpine-induced miosis caused the iris to assume a planar configuration in all subjects. This study shows that the iris in pigment dispersion syndrome assumes a planar configuration when fixating and that the concavity of the iris surface is not restored by blinking. Accommodation restored the iris concavity, suggesting that the posterior curvature of the iris in pigment dispersion syndrome is induced and probably maintained, at least in part, by accommodation. Copyright © 2011 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  11. Epigenetic regulation of MdMYB1 is associated with paper bagging-induced red pigmentation of apples.

    PubMed

    Bai, Songling; Tuan, Pham Anh; Saito, Takanori; Honda, Chikako; Hatsuyama, Yoshimichi; Ito, Akiko; Moriguchi, Takaya

    2016-09-01

    Paper-bagging treatment can transform non-transcribed MdMYB1 - 2 and MdMYB1 - 3 alleles into transcribed alleles through epigenetic regulations, resulting in the red pigmentation of a normally non-red apple cultivar 'Mutsu.' Anthocyanin biosynthesis in apples is regulated by MdMYB1/A/10, an R2R3-Type MYB gene. 'Mutsu,' a triploid apple cultivar harboring non-transcribed MdMYB1-2 and MdMYB1-3 alleles, retains green skin color under field conditions. However, it can show red/pink pigmentation under natural or artificial ultraviolet-B (UV-B) light exposure after paper-bagging and bag removal treatment. In the present study, we found that in 'Mutsu,' paper bagging-induced red pigmentation was due to the activation of non-transcribed MdMYB1-2/-3 alleles, which triggered the expression of downstream anthocyanin biosynthesis genes in a UV-B-dependent manner. By monitoring the epigenetic changes during UV-B-induced pigmentation, no significant differences in DNA methylation and histone modifications in the 5' upstream region of MdMYB1-2/-3 were recorded between the UV-B-treated fruit skin (red) and the fruit skin treated only by white light (green). In contrast, bag treatment lowered the DNA methylation in this region of MdMYB1-2/-3 alleles. Similarly, higher levels of histone H3 acetylation and trimethylation of H3 tail at lysine 4, and lower level of trimethylation of H3 tail at lysine 27 were observed in the 5' upstream region of MdMYB1-2/-3 in the skin of the fruit immediately after bag removal. These results suggest that bagging treatment can induce epigenetic changes, facilitating the binding of trans factor(s) to MdMYB1-2/-3 alleles, resulting in the activation of these MYBs after bag removal.

  12. 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

  13. Cultured skin substitutes reduce donor skin harvesting for closure of excised, full-thickness burns.

    PubMed

    Boyce, Steven T; Kagan, Richard J; Yakuboff, Kevin P; Meyer, Nicholas A; Rieman, Mary T; Greenhalgh, David G; Warden, Glenn D

    2002-02-01

    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. 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. 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. 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. 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.

  14. Pigmentary Markers in Danes – Associations with Quantitative Skin Colour, Nevi Count, Familial Atypical Multiple-Mole, and Melanoma Syndrome

    PubMed Central

    Johansen, Peter; Andersen, Jeppe Dyrberg; Madsen, Linnea Nørgård; Ullum, Henrik; Glud, Martin; Børsting, Claus; Gniadecki, Robert; Morling, Niels

    2016-01-01

    To investigate whether pigmentation genes involved in the melanogenic pathway (melanogenesis) contributed to melanoma predisposition, we compared pigmentary genetics with quantitative skin pigmentation measurements, the number of atypical nevi, the total nevus count, and the familial atypical multiple mole and melanoma (FAMMM) syndrome. We typed 32 pigmentary SNP markers and sequenced MC1R in 246 healthy individuals and 116 individuals attending periodic control for malignant melanoma development, 50 of which were diagnosed with FAMMM. It was observed that individuals with any two grouped MC1R variants (missense, NM_002386:c. 456C > A (p.TYR152*), or NM_002386:c.83_84insA (p.Asn29Glnfs*14) had significantly (p<0.001) lighter skin pigmentation of the upper-inner arm than those with none or one MC1R variant. We did not observe any significant association of the MC1R variants with constitutive pigmentation measured on the buttock area. We hypothesize that the effect of MC1R variants on arm pigmentation is primarily reflecting the inability to tan when subjected to UVR. A gender specific effect on skin pigmentation was also observed, and it was found that the skin pigmentation of females on average were darker than that of males (p<0.01). We conclude that MC1R variants are associated with quantitative skin colour in a lightly pigmented Danish population. We did not observe any association between any pigmentary marker and the FAMMM syndrome. We suggest that the genetics of FAMMM is not related to the genetics of the pigmentary pathway. PMID:26938746

  15. Central posterior capsule pigmentation in a patient with pigment dispersion and previous ocular trauma: A case report

    PubMed Central

    Al-Mezaine, Hani S

    2010-01-01

    We report a 55-year-old man with unusually dense, unilateral central posterior capsule pigmentation associated with the characteristic clinical features of pigment dispersion syndrome, including a Krukenberg's spindle and dense trabecular pigmentation in both eyes. A history of an old blunt ocular trauma probably caused separation of the anterior hyaloid from the back of the lens, thereby creating an avenue by which pigment could reach the potential space of Berger's from the posterior chamber. PMID:20534930

  16. Central posterior capsule pigmentation in a patient with pigment dispersion and previous ocular trauma: a case report.

    PubMed

    Al-Mezaine, Hani S

    2010-01-01

    We report a 55-year-old man with unusually dense, unilateral central posterior capsule pigmentation associated with the characteristic clinical features of pigment dispersion syndrome, including a Krukenberg's spindle and dense trabecular pigmentation in both eyes. A history of an old blunt ocular trauma probably caused separation of the anterior hyaloid from the back of the lens, thereby creating an avenue by which pigment could reach the potential space of Berger's from the posterior chamber.

  17. Imaging pigment chemistry in melanocytic conjunctival lesions with pump-probe microscopy

    NASA Astrophysics Data System (ADS)

    Wilson, Jesse W.; Vajzovic, Lejla; Robles, Francisco E.; Cummings, Thomas J.; Mruthyunjaya, Prithvi; Warren, Warren S.

    2013-03-01

    We extend nonlinear pump-probe microscopy, recently demonstrated to image the microscopic distribution of eumelanin and pheomelanin in unstained skin biopsy sections, to the case of melanocytic conjunctival lesions. The microscopic distribution of pigmentation chemistry serves as a functional indicator of melanocyte activity. In these conjunctival specimens (benign nevi, primary acquired melanoses, and conjunctival melanoma), we have observed pump-probe spectroscopic signatures of eumelanin, pheomelanin, hemoglobin, and surgical ink, in addition to important structural features that differentiate benign from malignant lesions. We will also discuss prospects for an in vivo `optical biopsy' to provide additional information before having to perform invasive procedures.

  18. Lasers and ancillary treatments for scar management Part 2: Keloid, hypertrophic, pigmented and acne scars

    PubMed Central

    McGoldrick, Rory Boyd; Theodorakopoulou, Evgenia; Azzopardi, Ernest Anthony; Murison, Maxwell

    2017-01-01

    The formation of a wide range of excessive scars following various skin injuries is a natural consequence of healing. Scars resulting from surgery or trauma affect approximately 100 million people per annum in the developed world and can have profound physical, aesthetic, psychological and social consequences. Thus, scar treatment is a priority for patient and physician alike. Laser treatment plays an important role in scar management with additional support from ancillary modalities. Subsequent to part 1: Burns scars, part 2 focuses on our strategies and literature review of treatment of keloid, hypertrophic, pigmented and acne scars where lasers are used in conjunction with other measures, and illustrated with case studies. PMID:29799579

  19. Interventions for photodamaged skin.

    PubMed

    Samuel, M; Brooke, R C C; Hollis, S; Griffiths, C E M

    2005-01-25

    Photodamage describes skin changes such as fine and coarse wrinkles, roughness, freckles and pigmentation changes that occur as a result of prolonged exposure to the sun. Many treatments are available to reverse the damage, but it is unclear which work and at what cost in terms of unwanted side effects. To assess the effects of topically applied treatments, tablet treatments, laser and surgical procedures for photodamaged skin. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, Issue 1 2002, MEDLINE (1966-June 2002), EMBASE (1974-June 2002), Health Periodicals (1976-June 2002). We checked references of articles and communicated with authors and the pharmaceutical industry. Randomised controlled trials which compared drug or surgical interventions with no treatment, placebo or another drug, in adults with mild, moderate or severe photodamage of the face or forearms. Two reviewers independently extracted data and assessed trial quality. Thirty studies of variable quality were included. Eight trials showed that topical tretinoin cream, in concentrations of 0.02% or higher, was superior to placebo for participants with mild to severe photodamage on the face and forearms (although losses to follow-up were relatively high in most studies). For example, the relative risk of improvement for 0.05% tretinoin cream, compared to placebo (three studies), at 24 weeks, was 1.73 (95% confidence interval 1.39 to 2.14). This effect was not seen for 0.001% topical tretinoin (one study) or 0.01% (three studies). A dose-response relationship was evident for both effectiveness and skin irritation. One small within-patient study showed benefit from topical ascorbic acid compared with placebo. Tazarotene (0.01% to 0.1%) and isotretinoin (0.1%) both showed significant improvement over placebo for moderate photodamage (one study each). There is limited evidence (one trial), to show that the effectiveness of 0.05% tretinoin, is equivalent to the

  20. Genetic modifiers of abnormal organelle biogenesis in a Drosophila model of BLOC-1 deficiency

    PubMed Central

    Cheli, Verónica T.; Daniels, Richard W.; Godoy, Ruth; Hoyle, Diego J.; Kandachar, Vasundhara; Starcevic, Marta; Martinez-Agosto, Julian A.; Poole, Stephen; DiAntonio, Aaron; Lloyd, Vett K.; Chang, Henry C.; Krantz, David E.; Dell'Angelica, Esteban C.

    2010-01-01

    Biogenesis of lysosome-related organelles complex 1 (BLOC-1) is a protein complex formed by the products of eight distinct genes. Loss-of-function mutations in two of these genes, DTNBP1 and BLOC1S3, cause Hermansky–Pudlak syndrome, a human disorder characterized by defective biogenesis of lysosome-related organelles. In addition, haplotype variants within the same two genes have been postulated to increase the risk of developing schizophrenia. However, the molecular function of BLOC-1 remains unknown. Here, we have generated a fly model of BLOC-1 deficiency. Mutant flies lacking the conserved Blos1 subunit displayed eye pigmentation defects due to abnormal pigment granules, which are lysosome-related organelles, as well as abnormal glutamatergic transmission and behavior. Epistatic analyses revealed that BLOC-1 function in pigment granule biogenesis requires the activities of BLOC-2 and a putative Rab guanine-nucleotide-exchange factor named Claret. The eye pigmentation phenotype was modified by misexpression of proteins involved in intracellular protein trafficking; in particular, the phenotype was partially ameliorated by Rab11 and strongly enhanced by the clathrin-disassembly factor, Auxilin. These observations validate Drosophila melanogaster as a powerful model for the study of BLOC-1 function and its interactions with modifier genes. PMID:20015953

  1. 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 neoplasmsmore » 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)« less

  2. 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. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Abnormal uterine bleeding.

    PubMed

    Cheong, Ying; Cameron, Iain T; Critchley, Hilary O D

    2017-09-01

    It is not uncommon for a woman to suffer from abnormal uterine bleeding (AUB) or heavy menstrual bleeding (HMB) at some point during her lifetime. Once pathology is excluded, in practice, management needs to be individualised, taking into account the improvement of the woman's symptoms and quality of life. Peer-reviewed journals, governmental and professional society publications. There is now agreement on a structured, universal approach to the diagnosis of AUB, with the aide memoirs PALM (polyps, adenomyosis, leiomyoma, malignancy) and COEIN (coagulopathies, ovulatory dysfunction, endometrial, iatrogenic, not otherwise classified). Once malignancy and significant pelvic pathology have been ruled out, medical treatment is an effective first-line therapeutic option, with surgery, including endometrial ablation and hysterectomy, offered when medical management has failed to resolve symptoms and fertility is no longer desired. There remains controversy around the management of the types and subtypes of adenomyosis and leiomyoma, and understanding their impact on clinical reproductive outcomes. Standardised assessment tools for measuring outcomes of AUB are being developed. Novel diagnostic and monitoring tools should be developed to help stratify treatment for women with AUB, particularly relating to 'unclassified' and 'endometrial' causes. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  4. Communication and abnormal behaviour.

    PubMed

    Crown, S

    1979-01-01

    In this paper the similarities between normal and abnormal behaviour are emphasized and selected aspects of communication, normal and aberrant, between persons are explored. Communication in a social system may be verbal or non-verbal: one person's actions cause a response in another person. This response may be cognitive, behavioural or physiological. Communication may be approached through the individual, the social situation or social interaction. Psychoanalysis approaches the individual in terms of the coded communications of psychoneurotic symptoms or psychotic behaviour; the humanist-existential approach is concerned more with emotional expression. Both approaches emphasize the development of individual identity. The interaction between persons and their social background is stressed. Relevant are sociological concepts such as illness behaviour, stigma, labelling, institutionalization and compliance. Two approaches to social interactions are considered: the gamesplaying metaphor, e.g. back pain as a psychosocial manipulation--the 'pain game'; and the 'spiral of reciprocal perspectives' which emphasizes the interactional complexities of social perceptions. Communicatory aspects of psychological treatments are noted: learning a particular metaphor such as 'resolution' of the problem (psychotherapy), learning more 'rewarding' behaviour (learning theory) or learning authenticity or self-actualization (humanist-existential).

  5. Autoshaping of abnormal children.

    PubMed

    Deckner, C W; Wilcox, L M; Maisto, S A; Blanton, R L

    1980-09-01

    Three experimentally naive abnormal children were exposed to a terminal operant contingency, i.e., reinforcement was delivered only if the children pressed a panel during intervals when it was lighted. Despite the absence of both successive approximation and manual shaping, it was found that each child began to respond discriminatively within a small number of trials. These data replicated previous animal studies concerned with the phenomena of autoshaping and signal-controlled responding. It was also found, however, that one type of autoshaping, the classical conditioning procedure, had a powerful suppressive effect on the discriminative responding. An experimental analysis that consisted procedure, had a powerful suppressive effect on discriminative responding. An experimental analysis that consisted of intrasubject reversal an multiple baseline designs established the internal validity of the findings. The finding of rapid acquisition of signal-controlled responding obtained with the initial procedure is suggessted to have practical significance. The disruptive effects of the classical form of autoshaping are discussed in terms of negative behavioral contrast.

  6. Variation in Hsp70-1A expression contributes to skin color diversity

    PubMed Central

    Murase, Daiki; Hachiya, Akira; Fullenkamp, Rachel; Beck, Anita; Moriwaki, Shigeru; Hase, Tadashi; Takema, Yoshinori; Manga, Prashiela

    2017-01-01

    The wide range in human skin color results from varying levels of the pigment melanin. Genetic mechanisms underlying coloration differences have been explored, but identified genes do not account for all variation seen in the skin color spectrum. Post-transcriptional and post-translational regulation of factors that determine skin color, including melanin synthesis in epidermal melanocytes, melanosome transfer to keratinocytes and melanosome degradation, is also critical for pigmentation. We therefore investigated proteins that are differentially expressed in melanocytes derived from either White or African American (AA) skin. Two dimensional gel electrophoresis (2-DGE) and mass spectrometry demonstrated that Heat Shock Protein 70-1A (Hsp70-1A) protein levels were significantly higher in AA melanocytes compared to White melanocytes. Hsp70-1A expression significantly correlated with levels of tyrosinase, the rate-limiting melanogenic enzyme, consistent with a proposed role for Hsp70-family members in tyrosinase post-translational modification. Additionally, pharmacologic inhibition and siRNA-mediated down-regulation of Hsp70-1A correlated with pigmentation changes in cultured melanocytes, modified human skin substitutes and ex vivo skin. Furthermore, Hsp70-1A inhibition led to increased autophagy-mediated melanosome degradation in keratinocytes. Our data thus reveal that epidermal Hsp70-1A contributes to the diversity of skin color by regulating the amount of melanin synthesized in melanocytes and modulating autophagic melanosome degradation in keratinocytes. PMID:27094592

  7. The Yucatan miniature swine as an in vivo model for screening skin depigmentation.

    PubMed

    Nair, X; Tramposch, K M

    1991-12-01

    The usefulness of the Yucatan miniature pig as a screen for skin dipigmenting activity by topical application was evaluated with standard compounds. This is a naturally occurring breed of swine with light brown to dark brown skin that is relatively hairless. The skin morphology, including the pattern of pigment distribution, in this breed of swine closely resembles the human skin. Test compounds examined in this study included the three standard compounds with known clinical depigmenting activity, hydroquinone (HQ), 4-hydroxyanisole (4HA) and tert-butyl catechol (TBC), each at a 5% concentration. Test materials in 25 microliters of propylene glycol/ethanol (50:50) were applied topically twice daily, 7 days a week for 90 days to test sites on each side of the dorsal mid-line. Test sites were graded weekly for variation in pigmentation and local irritation. After 90 days of test material application, skin biopsies of the test sites were taken for histological evaluation. Topical application of HQ, 4HA and TBC promoted marked skin depigmentation which was substantiated by reductions of pigment and melanocytes observed on microscopic examination. While both HQ and TBC produced marked local irritation, 4HA was only mildly irritating. These results suggest that the Yucatan pig, could be a potentially useful model for screening compounds with skin depigmenting activity.

  8. Variation in Hsp70-1A Expression Contributes to Skin Color Diversity.

    PubMed

    Murase, Daiki; Hachiya, Akira; Fullenkamp, Rachel; Beck, Anita; Moriwaki, Shigeru; Hase, Tadashi; Takema, Yoshinori; Manga, Prashiela

    2016-08-01

    The wide range in human skin color results from varying levels of the pigment melanin. Genetic mechanisms underlying coloration differences have been explored, but identified genes do not account for all variation seen in the skin color spectrum. Post-transcriptional and post-translational regulation of factors that determine skin color, including melanin synthesis in epidermal melanocytes, melanosome transfer to keratinocytes, and melanosome degradation, is also critical for pigmentation. We therefore investigated proteins that are differentially expressed in melanocytes derived from either white or African American skin. Two-dimensional gel electrophoresis and mass spectrometry demonstrated that heat shock protein 70-1A (Hsp70-1A) protein levels were significantly higher in African American melanocytes compared with white melanocytes. Hsp70-1A expression significantly correlated with levels of tyrosinase, the rate-limiting melanogenic enzyme, consistent with a proposed role for Hsp70 family members in tyrosinase post-translational modification. In addition, pharmacologic inhibition and small interfering RNA-mediated downregulation of Hsp70-1A correlated with pigmentation changes in cultured melanocytes, modified human skin substitutes, and ex vivo skin. Furthermore, Hsp70-1A inhibition led to increased autophagy-mediated melanosome degradation in keratinocytes. Our data thus reveal that epidermal Hsp70-1A contributes to the diversity of skin color by regulating the amount of melanin synthesized in melanocytes and modulating autophagic melanosome degradation in keratinocytes. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  9. 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

  10. Skin color variation in Orang Asli tribes of Peninsular Malaysia.

    PubMed

    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.

  11. Adaptation of human skin color in various populations.

    PubMed

    Deng, Lian; Xu, Shuhua

    2018-01-01

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

  12. 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.

  13. Color me bad: microbial pigments as virulence factors

    PubMed Central

    Liu, George Y.; Nizet, Victor

    2009-01-01

    A hallmark feature of several pathogenic microbes is the distinctive color of their colonies when propagated in the clinical laboratory. Such pigmentation comes in a variety of hues, and has often proven useful in presumptive clinical diagnosis. Recent advances in microbial pigment biochemistry and the genetic basis of pigment production has sometimes revealed a more sinister aspect to these curious materials that change the color of reflected light by selective light absorbance. In many cases, the microbial pigment contributes to disease pathogenesis by interfering with host immune clearance mechanisms or by exhibiting pro-inflammatory or cytotoxic properties. Here, we review several examples of pigments that promote microbial virulence, including the golden staphyloxanthin of Staphylococcus aureus, the blue-green pyocyanin of Pseudomonas spp., and the dark brown or black melanin pigments of Cryptococcus neoformans and Aspergillus spp. Targeted pigment neutralization may represent a viable concept to enhance treatment of certain difficult infectious disease conditions. PMID:19726196

  14. STUDIES ON RADIATION-INDUCED TANNING OF SKIN

    SciTech Connect

    Quevedo, W.C. Jr.; Smith, J.A.

    1963-02-15

    After repeated exposure to uv, hyperpigmentation developed in the general body skin of hairless mice and in the plantar skin of mice of a number of strains selected on the basis of characteristic differences in coat coloration. The hyperpigmentation was due largely to an increase in melanin synthesis by epidermal melanocytes. The major coat color genes had a profound effect on this process by having an influence on melanocyte distribution and, possibly, proliferation; the numbers of melanocytes activated by uv radiation; the amount of pigment synthesized by melanocytes, either retained by them or transferred to epidermal cells; the color andmore » size of pigment granules elaborated by melandocytes; and the shape of the melanocytes. Possible mechanisms involved in the response of epidermal melanocytes to radiations are discussed. (auth)« less

  15. 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

  16. Fungal Skin Infections

    MedlinePlus

    ... Skin Infections Overview of Fungal Skin Infections Candidiasis (Yeast Infection) Dermatophytid Reaction Intertrigo Tinea Versicolor Overview of ... breasts. Common fungal skin infections are caused by yeasts (such as Candida or Malassezia furfur ) or dermatophytes , ...

  17. Skin care and incontinence

    MedlinePlus

    ... skin problems such as redness, peeling, irritation, and yeast infections likely. Bedsores ( pressure sores ) may also develop ... drying the skin. Incontinence problems can cause a yeast infection on the skin. This is an itchy, ...

  18. Skin color - patchy

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003224.htm Skin color - patchy To use the sharing features on this page, please enable JavaScript. Patchy skin color is areas where the skin color is irregular. ...

  19. Histoplasma skin test

    MedlinePlus

    Histoplasmosis skin test ... health care provider cleans an area of your skin, usually the forearm. An allergen is injected just below the cleaned skin surface. An allergen is a substance that causes ...

  20. 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 ...

  1. Skin Cancer Foundation

    MedlinePlus

    ... You at Risk? UVA & UVB Skin of Color Tanning Teacher Resources Related: What Is Skin Cancer? | Window ... Tribute Page | Share Your Story | Skin Cancer Information | Tanning | Get Involved Healthy Lifestyle Go With Your Own ...

  2. Generic Algorithms for Estimating Foliar Pigment Content

    NASA Astrophysics Data System (ADS)

    Gitelson, Anatoly; Solovchenko, Alexei

    2017-09-01

    Foliar pigment contents and composition are main factors governing absorbed photosynthetically active radiation, photosynthetic activity, and physiological status of vegetation. In this study the performance of nondestructive techniques based on leaf reflectance were tested for estimating chlorophyll (Chl) and anthocyanin (AnC) contents in species with widely variable leaf structure, pigment content, and composition. Only three spectral bands (green, red edge, and near-infrared) are required for nondestructive Chl and AnC estimation with normalized root-mean-square error (NRMSE) below 4.5% and 6.1%, respectively. The algorithms developed are generic, not requiring reparameterization for each species allowing for accurate nondestructive Chl and AnC estimation using simple handheld field/lab instrumentation. They also have potential in interpretation of airborne and satellite data.

  3. Animal pigment bilirubin discovered in plants.

    PubMed

    Pirone, Cary; Quirke, J Martin E; Priestap, Horacio A; Lee, David W

    2009-03-04

    The bile pigment bilirubin-IXalpha is the degradative product of heme, distributed among mammals and some other vertebrates. It can be recognized as the pigment responsible for the yellow color of jaundice and healing bruises. In this paper we present the first example of the isolation of bilirubin in plants. The compound was isolated from the brilliant orange-colored arils of Strelitzia nicolai, the white bird of paradise tree, and characterized by HPLC-ESMS, UV-visible, (1)H NMR, and (13)C NMR spectroscopy, as well as comparison with an authentic standard. This discovery indicates that plant cyclic tetrapyrroles may undergo degradation by a previously unknown pathway. Preliminary analyses of related plants, including S. reginae, the bird of paradise, also revealed bilirubin in the arils and flowers, indicating that the occurrence of bilirubin is not limited to a single species or tissue type.

  4. Pigmented villonodular synovitis of the hip.

    PubMed

    Steinmetz, Sylvain; Rougemont, Anne-Laure; Peter, Robin

    2016-06-01

    Pigmented villonodular synovitis (PVNS) is a rare disease that can affect any joint, bursa or tendon sheath.The hip is less frequently affected than the knee, and hence is less discussed in scientific journals.PVNS of the hip mainly occurs in young adults, requiring early diagnosis and adequate treatment to obtain good results.There is no consensus on the management of PVNS of the hip in current literature.We will discuss the options for surgical intervention in hip PVNS using a literature review of clinical, biological, etiological, histological and radiographic aspects of the disease. Cite this article: Steinmetz S, Rougemont A-L, Peter R. Pigmented villonodular synovitis of the hip. EFORT Open Rev 2016;1:260-266. DOI: 10.1302/2058-5241.1.000021.

  5. Bleeding into the skin

    MedlinePlus

    ... red; Pinpoint red spots on the skin; Petechiae; Purpura ... in the newborn) Aging skin (ecchymosis) Idiopathic thrombocytopenic purpura (petechiae and purpura) Henoch-Schonlein purpura (purpura) Leukemia ( ...

  6. Accuracy in clinically evaluating pigmented lesions.

    PubMed Central

    Curley, R. K.; Cook, M. G.; Fallowfield, M. E.; Marsden, R. A.

    1989-01-01

    OBJECTIVE--To determine the ability of three doctors experienced in managing melanocytic lesions to diagnose correctly melanoma, dysplastic naevi, and various benign pigmented lesions. DESIGN--Independent clinical evaluation and histopathological assessment. SETTING--Pigmented lesion clinic, which patients attend without an appointment for early diagnosis of melanoma. PATIENTS--86 Patients with lesions that were judged to be benign by at least one of the three doctors. INTERVENTIONS--The lesions were excised under local anaesthesia and sent for histopathological examination in coded bottles without clinical details. MAIN OUTCOME MEASURE--Comparison of clinical with histopathological diagnosis for each lesion. RESULTS--A total of 120 lesions were evaluated by at least two of the three doctors. The histopathological diagnoses were made by the same pathologist. The overall sensitivity (diagnostic accuracy) for the three doctors for all types of lesion was 50%. Of the 39 dysplastic naevi, only 19 were identified correctly by all observers, and a further 24 banal lesions were wrongly diagnosed as dysplastic by at least one doctor. Particular difficulty was experienced with small (less than 5 mm), flat lesions, which can be banal or potentially malignant. CONCLUSIONS--Critical diagnosis and management decisions concerning pigmented lesions should always be based on a combination of clinical and histopathological assessments and the history of the patient. PMID:2503192

  7. Localization and seasonal variation of blue pigment (sandercyanin) in walleye (Sander vitreus)

    USGS Publications Warehouse

    Schaefer, Wayne; Schmitz, Mark; Blazer, Vicki S.; Ehlinger, Tim; Berges, John

    2015-01-01

    Several fish species, including the walleye (Sander vitreus), have “yellow” and “blue” color morphs. In S. vitreus, one source of the blue color has been identified as a bili-binding protein pigment (sandercyanin), found in surface mucus of the fish. Little is known about the production of the pigment or about its functions. We examined the anatomical localization and seasonal variation of sandercyanin in S. vitreus from a population in McKim Lake, northwestern Ontario, Canada. Skin sections were collected from 20 fish and examined histologically. Mucus was collected from 306 fish over 6 years, and the amount of sandercyanin was quantified spectrophotometrically. Sandercyanin was found solely on dorsal surfaces of the fish and was localized to novel cells in the epidermis, similar in appearance to secretory sacciform cells. Sandercyanin concentrations were significantly higher in fish collected in summer versus other seasons. Yellow and blue morphs did not differ in amounts of sandercyanin, suggesting that the observed blue color, in fact, arises from lack of yellow pigmentation in blue morphs. The function of the sandercyanin remains unclear, but roles in photoprotection and countershading are consistent with available data.

  8. Biology and genetics of oculocutaneous albinism and vitiligo - common pigmentation disorders in southern Africa.

    PubMed

    Manga, Prashiela; Kerr, Robyn; Ramsay, Michèle; Kromberg, Jennifer G R

    2013-07-29

    Pigmentation disorders span the genetic spectrum from single-gene autosomal recessive disorders such as oculocutaneous albinism (OCA), the autosomal dominant disorder piebaldism to X-linked ocular albinism and multifactorial vitiligo. OCA connotes a group of disorders that result in hypopigmented skin due to decreased melanin production in melanocytes and loss of visual acuity. There are four non-syndromic forms, OCA1-4, which are classified based on the gene that is mutated (tyrosinase, OCA2, tyrosinase-related protein 1 and SLC45A2, respectively). Despite the fact that multiple genes account for the various forms of OCA, the phenotypes of all four forms result from disruption in the maturation and trafficking of the enzyme tyrosinase. OCA2 is the most prevalent autosomal recessive disorder among southern African blacks, affecting 1/3 900 individuals; while OCA3, although rare, is most prevalent in southern Africa. Another common pigmentation disorder in southern Africa is vitiligo, which affects 1 - 2% of people worldwide. Vitiligo is a complex, acquired disorder in which melanocytes are destroyed due to an autoimmune response. The aetiology underlying this disorder is poorly understood, although recent genetic association studies have begun to shed light on the contributing factors. Pigmentation disorders have significant psychosocial implications and co-morbidities, yet therapies are still lacking. Recent progress in our understanding of the pathobiology of both albinism and vitiligo may herald novel treatment strategies for these disorders. 

  9. Acral peeling skin syndrome: report of two cases.

    PubMed

    García, Elena García; Carreño, Rosario Granados; Martínez González, Miguel A; Reyes, José Jiménez

    2005-01-01

    Peeling skin syndrome is a rare dermatosis characterized by spontaneous and painless peeling of the skin. The authors report two patients with history of spontaneous, asymptomatic, and noninflammatory peeling skin of the acral surfaces after soaking in water. On light microscopy, blisters were located in the mid layers of the stratum corneum, above the granular layer. Ultrastructural examination revealed increased intercellular lipids and abnormal, "moth-eaten," keratohyalin granules, but the authors were unable to determine whether the separation initiated within the horny cells or between adjacent cells. These patients represented a localized variant of peeling skin syndrome.

  10. 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.

  11. Formation mechanism of complex pattern on fishes' skin

    NASA Astrophysics Data System (ADS)

    Li, Xia; Liu, Shuhua

    2009-10-01

    In this paper, the formation mechanism of the complex patterns observed on the skin of fishes has been investigated by a two-coupled reaction diffusion model. The effects of coupling strength between two layers play an important role in the pattern-forming process. It is found that only the epidermis layer can produce complicated patterns that have structures on more than one length scale. These complicated patterns including super-stripe pattern, mixture of spots and stripe, and white-eye pattern are similar to the pigmentation patterns on fishes' skin.

  12. [Skin aging and evidence-based topical strategies].

    PubMed

    Bayerl, C

    2016-02-01

    Anti-aging in dermatology primarily focuses on the prevention of skin aging with UV protection (clothing and sunsceens), free radical scavengers (synthetic or botanic), and cell-protecting agents such as vitamin B3. For the correction of signs of early skin aging, retinoic acid derivatives in dermatological prescriptions are the best studied substances. Topical hormonal prescriptions are also an option if UV damage has not been the leading culprit for aging. Chemical peeling leads to a marked increase in collagen formation, the deaper the better. Ingredients in cream preparations can reduce superficial skin folds (polyphenols, amino acid peptides). Modulators of regular pigmentation are important for anti-aging preparations. Growth factors (plant extracts, recombinant growth factors) are not thoroughly studied regarding the cost-benefit and risk ratio. Complex precedures such as photodynamic therapy have an impact on the appearance of aged skin.

  13. Study on application of optical clearing technique in skin diseases

    NASA Astrophysics Data System (ADS)

    Shan, Hao; Liang, Yanmei; Wang, Jingyi; Li, Yan

    2012-11-01

    So far, the study of the optical clearing is almost always about healthy tissue. However, the ultimate goal is to detect diseases for clinical application. Optical clearing on diseased skins is explored. The effect is evaluated by applying a combined liquid paraffin and glycerol mixed solution on several kinds of diseased skins in vitro. Scanning experiments from optical coherence tomography show that it has different effects among fibroma, pigmented nevus, and seborrheic keratosis. Based on the results, we conclude that different skin diseases have different compositions and structures, and their optical parameters and biological characteristics should be different, which implies that the optical clearing technique may have selectivity and may not be suitable for all kinds of skin diseases.

  14. Lactic acid peeling in superficial acne scarring in Indian skin.

    PubMed

    Sachdeva, Silonie

    2010-09-01

    Chemical peeling with both alpha and beta hydroxy acids has been used to improve acne scarring with pigmentation. Lactic acid, a mild alpha hydroxy acid, has been used in the treatment of various dermatological indications but no study is reported in acne scarring with pigmentation. To evaluate the efficacy and safety of full strength pure lactic acid 92% (pH 2.0) chemical peel in superficial acne scarring in Indian skin. Seven patients, Fitzpatrick skin type IV-V, in age group 20-30 years with superficial acne scarring were enrolled in the study. Chemical peeling was done with lactic acid at an interval of 2 weeks to a maximum of four peels. Pre- and post-peel clinical photographs were taken at every session. Patients were followed every month for 3 months after the last peel to evaluate the effects. At the end of 3 months, there was definite improvement in the texture, pigmentation, and appearance of the treated skin, with lightening of scars. Significant improvement (greater than 75% clearance of lesions) occurred in one patient (14.28%), good improvement (51-75% clearance) in three patients (42.84%), moderate improvement (26-50% clearance) in two patients (28.57%), and mild improvement (1-25% clearance) in one patient (14.28%). © 2010 Wiley Periodicals, Inc.

  15. Melanocortin-1 Receptor Polymorphisms and Risk of Melanoma: Is the Association Explained Solely by Pigmentation Phenotype?

    PubMed Central

    Palmer, James S.; Duffy, David L.; Box, Neil F.; Aitken, Joanne F.; O'Gorman, Louise E.; Green, Adele C.; Hayward, Nicholas K.; Martin, Nicholas G.; Sturm, Richard A.

    2000-01-01

    Summary Risk of cutaneous malignant melanoma (CMM) is increased in sun-exposed whites, particularly those with a pale complexion. This study was designed to investigate the relationship of the melanocortin-1 receptor (MC1R) genotype to CMM risk, controlled for pigmentation phenotype. We report the occurrence of five common MC1R variants in an Australian population-based sample of 460 individuals with familial and sporadic CMM and 399 control individuals—and their relationship to such other risk factors as skin, hair, and eye color; freckling; and nevus count. There was a strong relationship between MC1R variants and hair color and skin type. Moreover, MC1R variants were found in 72% of the individuals with CMM, whereas only 56% of the control individuals carried at least one variant (P<.001), a finding independent of strength of family history of melanoma. Three active alleles (Arg151Cys, Arg160Trp, and Asp294His), previously associated with red hair, doubled CMM risk for each additional allele carried (odds ratio 2.0; 95% confidence interval 1.6–2.6). No such independent association could be demonstrated with the Val60Leu and Asp84Glu variants. Among pale-skinned individuals alone, this association between CMM and MC1R variants was absent, but it persisted among those reporting a medium or olive/dark complexion. We conclude that the effect that MC1R variant alleles have on CMM is partly mediated via determination of pigmentation phenotype and that these alleles may also negate the protection normally afforded by darker skin coloring in some members of this white population. PMID:10631149

  16. The male beard hair and facial skin - challenges for shaving.

    PubMed

    Maurer, M; Rietzler, M; Burghardt, R; Siebenhaar, F

    2016-06-01

    The challenge of shaving is to cut the beard hair as closely as possible to the skin without unwanted effects on the skin. To achieve this requires the understanding of beard hair and male facial skin biology as both, the beard hair and the male facial skin, contribute to the difficulties in obtaining an effective shave without shaving-induced skin irritation. Little information is available on the biology of beard hairs and beard hair follicles. We know that, in beard hairs, the density, thickness, stiffness, as well as the rates of elliptical shape and low emerging angle, are high and highly heterogeneous. All of this makes it challenging to cut it, and shaving techniques commonly employed to overcome these challenges include shaving with increased pressure and multiple stroke shaving, which increase the probability and extent of shaving-induced skin irritation. Several features of male facial skin pose problems to a perfect shave. The male facial skin is heterogeneous in morphology and roughness, and male skin has a tendency to heal slower and to develop hyperinflammatory pigmentation. In addition, many males exhibit sensitive skin, with the face most often affected. Finally, the hair follicle is a sensory organ, and the perifollicular skin is highly responsive to external signals including mechanical and thermal stimulation. Perifollicular skin is rich in vasculature, innervation and cells of the innate and adaptive immune system. This makes perifollicular skin a highly responsive and inflammatory system, especially in individuals with sensitive skin. Activation of this system, by shaving, can result in shaving-induced skin irritation. Techniques commonly employed to avoid shaving-induced skin irritation include shaving with less pressure, pre- and post-shave skin treatment and to stop shaving altogether. Recent advances in shaving technology have addressed some but not all of these issues. A better understanding of beard hairs, beard hair follicles and male

  17. Interaction between Vaccinium bracteatum Thunb. leaf pigment and rice proteins.

    PubMed

    Wang, Li; Xu, Yuan; Zhou, Sumei; Qian, Haifeng; Zhang, Hui; Qi, Xiguang; Fan, Meihua

    2016-03-01

    In this study, we investigated the interaction of Vaccinium bracteatum Thunb. leaf (VBTL) pigment and rice proteins. In the presence of rice protein, VBTL pigment antioxidant activity and free polyphenol content decreased by 67.19% and 68.11%, respectively, and L(∗) of the protein-pigment complex decreased significantly over time. L(∗) values of albumin, globulin and glutelin during 60-min pigment exposure decreased by 55.00, 57.14, and 54.30%, respectively, indicating that these proteins had bound to the pigment. A significant difference in protein surface hydrophobicity was observed between rice proteins and pigment-protein complexes, indicating that hydrophobic interaction is a major binding mechanism between VBTL pigment and rice proteins. A significant difference in secondary structures between proteins and protein-pigment complexes was also uncovered, indicating that hydrogen bonding may be another mode of interaction between VBTL pigment and rice proteins. Our results indicate that VBTL pigment can stain rice proteins with hydrophobic and hydrogen interactions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Study on the autofluorescence profiles of iris pigment epithelium and retinal pigment epithetlium

    NASA Astrophysics Data System (ADS)

    Xu, Gaixia; Qu, Junle; Chen, Danni; Sun, Yiwen; Zhao, Lingling; Lin, Ziyang; Ding, Zhihua; Niu, Hanben

    2007-05-01

    Transplantation technique of retinal pigment epithelium has been noticeable in recent years and gradually put into clinical practice in treatment of retinal degenerative diseases. Generally, immunological, histochemical, and physical methods are used to study the iris pigment epithelium (IPE) and retinal pigment epithelium (RPE) cells, which need complex sample preparation. In this paper, we provided a simple autofluorescence microscopy to investigate the fresh porcine IPE and RPE cells without any pretreatment. The results showed that the morphology and size of both were similar, round and about 15 μm. The main flourophore in both cells was similar, i.e. lipofuscin. In additional, the autofluorescence spectrum of RPE shifted blue after light-induced damage by laser illuminating. Because it was easier for IPE to be damaged by laser than for RPE, and the power of one scanning operation to get a full image was strong enough to damage IPE sample, we hadn't get any satisfied autofluorescence spectrum of IPE.

  19. Origins of adult pigmentation: diversity in pigment stem cell lineages and implications for pattern evolution

    PubMed Central

    Spiewak, Jessica E.

    2014-01-01

    Summary Teleosts comprise about half of all vertebrate species and exhibit an extraordinary diversity of adult pigment patterns that function in shoaling, camouflage and mate choice and have played important roles in speciation. Here, we review recent studies that have identified several distinct neural crest lineages, with distinct genetic requirements, that give rise to adult pigment cells in fishes. These lineages include post-embryonic, peripheral nerve associated stem cells that generate black melanophores and iridescent iridophores, cells derived directly from embryonic neural crest cells that generate yellow-orange xanthophores, and bipotent stem cells that generate both melanophores and xanthophores. This complexity in adult chromatophore lineages has implications for our understanding of adult traits, melanoma, and the evolutionary diversification of pigment cell lineages and patterns. PMID:25421288

  20. Detecting early stage pressure ulcer on dark skin using multispectral imager

    NASA Astrophysics Data System (ADS)

    Yi, Dingrong; Kong, Linghua; Sprigle, Stephen; Wang, Fengtao; Wang, Chao; Liu, Fuhan; Adibi, Ali; Tummala, Rao

    2010-02-01

    We are developing a handheld multispectral imaging device to non-invasively inspect stage I pressure ulcers in dark pigmented skins without the need of touching the patient's skin. This paper reports some preliminary test results of using a proof-of-concept prototype. It also talks about the innovation's impact to traditional multispectral imaging technologies and the fields that will potentially benefit from it.