Sample records for natural skin whitening

  1. 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

  2. The skin whitening industry in the Philippines.

    PubMed

    Mendoza, Roger Lee

    2014-05-01

    Skin whitening is a big and booming industry in many developing countries. Its popularity owes mainly to post-colonial, internalized racism. This study examines whether government intervention is necessary and more efficient than market-driven approaches in addressing the health risks and harms associated with skin whitening. We gathered empirical data on the quality and quantity of health-related information about skin whiteners with a multi-stage probability sample of consumers in two cities in the Philippines (n=110; α=0.05). Regardless of their socio-demographic characteristics, we find that cognitive biases and information asymmetries build and sustain consumers' trust in manufacturers and distributors of skin whiteners while, paradoxically, breeding uncertainties over the integrity of these products. The results are product adulteration and misbranding, leading to pricing advantages for toxic whiteners over safer products. This has impeded regulatory efficacy. We recommend anchoring government intervention in transaction cost-reduction, containing the externalities of skin bleaching, and institutionalizing third party partnerships. Failure to do so would leave consumers extremely vulnerable to the forces of supply and demand that favor toxic whiteners, particularly in a market where voluntary collective action is difficult to organize.

  3. A Game-Theoretic Model of Marketing Skin Whiteners.

    PubMed

    Mendoza, Roger Lee

    2015-01-01

    Empirical studies consistently find that people in less developed countries tend to regard light or "white" skin, particularly among women, as more desirable or superior. This is a study about the marketing of skin whiteners in these countries, where over 80 percent of users are typically women. It proceeds from the following premises: a) Purely market or policy-oriented approaches toward the risks and harms of skin whitening are cost-inefficient; b) Psychosocial and informational factors breed uninformed and risky consumer choices that favor toxic skin whiteners; and c) Proliferation of toxic whiteners in a competitive buyer's market raises critical supplier accountability issues. Is intentional tort a rational outcome of uncooperative game equilibria? Can voluntary cooperation nonetheless evolve between buyers and sellers of skin whiteners? These twin questions are key to addressing the central paradox in this study: A robust and expanding buyer's market, where cheap whitening products abound at a high risk to personal and societal health and safety. Game-theoretic modeling of two-player and n-player strategic interactions is proposed in this study for both its explanatory and predictive value. Therein also lie its practical contributions to the economic literature on skin whitening.

  4. 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.

  5. Skin whitening effect of linoleic acid is enhanced by liposomal formulations.

    PubMed

    Shigeta, Yasutami; Imanaka, Hiromichi; Ando, Hideya; Ryu, Atsuko; Oku, Naoto; Baba, Naomichi; Makino, Taketoshi

    2004-04-01

    Linoleic acid (LA) is known to have a whitening effect on hyperpigmented skin, and is encapsulated in liposomes for topical application because of its low solubility in aqueous solution, although the effect of liposomalization of LA on the whitening activity has not been evaluated. In the present study, we evaluated the effect of liposomalization on the whitening activity of LA by using LA in ethanol, hydrogel containing LA, and hydrogel containing liposomal LA towards the UV-stimulated hyperpigmented dorsal skin of brownish guinea pigs. The whitening effect was far greater for hydrogel containing liposomal LA (0.1% w/w as a final concentration of LA) than for free LA in ethanol or hydrogel containing LA. Next, the whitening effect of LA was examined with UV-stimulated hyperpigmented human upper arm skin by using a hydrogel containing liposomal LA (0.1% LA) and non-liposomal LA (3.0, 10.0% LA). Liposomal LA (0.1%) showed a whitening effect comparable to 10.0% non-liposomal LA and was far more effective than 3.0% non-liposomal LA. These results indicate that liposomal formulations are favorable for the transdermal application of LA.

  6. [Pandalao and skin whitening in Mayotte].

    PubMed

    Levang, J; Eygonnet, F; Humbert, P

    2009-10-01

    Skin whitening (SW) is very common in dark-skinned populations and the practice is often named after a popular local brand of product and such is the case in Mayotte where this practice is called "pandalao". We carried out a descriptive epidemiological study in a sample of black Mahoran women aged 15 and over. The survey comprised a questionnaire completed by 163 women between 12 November 2007 and 24 January 2008. The aim of our study was to investigate the practice of SW in Mayotte and to determine its prevalence. Hundred percent of the subjects were aware of SW and 95% knew people practicing this procedure. The prevalence of users of whitening products was 33%, although 74% of these subjects did not use such products on a regular basis and 89% of the women limited application to exposed areas (visible to others). Sixty-three percent simultaneously applied Diproson (betamethasone dipropionate) and Pandalao, the main component of which is salicylic acid. Fifty-four percent of users had presented one or more adverse effects after application of these products and 28% had stopped this practice due to such adverse effects (chiefly acne and dyschromia). Although illegal, the trade in skin whitening products continues to grow because it is profitable and takes full advantage of the success of ethnic cosmetics. In Mayotte, as in metropolitan France and Africa, the existence of SW is acknowledged but is still taboo. However, a number of specific characteristics are seen in Mayotte: SW is rarely performed on the whole body, salicylic acid is added to a topical corticosteroid, and the traditional Mahoran mask, the "mzindzano", is still worn for photoprotection.

  7. The Scientification of Skin Whitening and the Entrepreneurial University-Linked Corporate Scientific Officer

    ERIC Educational Resources Information Center

    Mire, Amina

    2012-01-01

    This work examines the interlocking strategies of scientific entrepreneurialism and academic capitalism in cutting-edge innovations in molecular biology, biomedicine, and other life sciences deployed in research and the development of high-end skin whitening and anti-aging cosmeceuticals. Skin whitening products and anti-aging cosmeceuticals are…

  8. A study of the human skin-whitening effects of resveratryl triacetate.

    PubMed

    Ryu, Ja Hyun; Seok, Jin Kyung; An, Sang Mi; Baek, Ji Hwoon; Koh, Jae Sook; Boo, Yong Chool

    2015-04-01

    Resveratrol has a variety of bioactivities that include its anti-melanogenic effects, but its use in cosmetics has been challenging partly because of its chemical instability. Resveratryl triacetate (RTA) is a prodrug that can enhance stability. The purpose of this study was to examine the skin safety and whitening effects of RTA in human subjects. The primary skin irritation potentials of RTA and resveratrol were tested at 0.1 and 0.5 % on human subjects. Resveratrol at a concentration of 0.5 % induced weak skin irritation, whereas RTA did not induce any skin responses. The skin-whitening efficacy of a cosmetic formulation containing 0.4 % RTA was evaluated in two different test models. In the artificial tanning model, the test product and the control product were applied twice daily to the skin of the forearms of 22 human subjects after pigmentation induction by ultraviolet irradiation. Applying the test and the control products to the artificial tanning model for 8 weeks increased the individual topology angles (ITA°) by 17.06 and 13.81 %, respectively, a difference that was statistically significant (p < 0.05). In the hyperpigmentation model, the test product and the control product were applied twice daily to the faces of 21 human subjects. The averaged intensity of the hyperpigmented spots decreased by 2.67 % in the test group and 1.46 % in the control group, a difference that was statistically significant (p < 0.05). Therefore, RTA incorporated into cosmetic formulations can whiten human skin without inducing skin irritation.

  9. Whitening effect of Sophora flavescens extract.

    PubMed

    Shin, Dae Hyun; Cha, Youn Jeong; Joe, Gi Jung; Yang, Kyeong Eun; Jang, Ik-Soon; Kim, Bo Hyeon; Kim, Jung Min

    2013-11-01

    Sophora flavescens Ait. (Leguminosae) has been proposed as a new whitening agent for cosmetics, because it has a strong ability to inhibit tyrosinase, a key enzyme in the formation of melanin. We conducted a study to determine whether ethanol extract of the roots of S. flavescens has the potential for use as a whitening cosmetic agent by investigating its underlying mechanisms of action. To elucidate the mechanism of action of S. flavescens extract, we used DNA microarray technology. We investigated the changes in the mRNA levels of genes associated with the formation and transport of melanosomes. We also identified the formation and transport of melanosomes with immunohistochemistry and immunofluorescence analyses. Finally, the skin-whitening effect in vivo of S. flavescens extract was analyzed on human skin. We found that S. flavescens extract strongly inhibited tyrosinase activity (IC50, 10.4 μg/mL). Results also showed that key proteins involved in the formation and transport of melanosomes were dramatically downregulated at both mRNA and protein level in keratinocytes exposed to S. flavescens extract. In addition, a clinical trial of a cream containing 0.05% S. flavescens extract on human skin showed it had a significant effect on skin whitening by mechanical and visual evaluation (1.14-fold). This study provides important clues toward understanding the effects of S. flavescens extract on the formation and transport of melanosomes. From these results, we suggest that naturally occurring S. flavescens extract might be useful as a new whitening agent in cosmetics.

  10. Overview of skin whitening agents with an insight into the illegal cosmetic market in Europe.

    PubMed

    Desmedt, B; Courselle, P; De Beer, J O; Rogiers, V; Grosber, M; Deconinck, E; De Paepe, K

    2016-06-01

    Lightening skin tone is an ancient and well-documented practice, and remains common practice among many cultures. Whitening agents such as corticosteroids, tretinoin and hydroquinone are medically applied to effectively lighten the skin tone of hyperpigmented lesions. However, when these agents are used cosmetically, they are associated with a variety of side-effect. Alternative agents, such as arbutin and its derivatives kojic acid and nicotinamide have been subsequently developed for cosmetic purposes. Unfortunately, some cosmetics contain whitening agents that are banned for use in cosmetic products. This article provides an overview of the mode of action and potential side-effects of cosmetic legal and illegal whitening agents, and the pattern of use of these types of products. Finally, an EU analysis of the health problems due to the presence of illegal products on the market is summarized. © 2016 European Academy of Dermatology and Venereology.

  11. Quantitative determination of a-Arbutin, ß-Arbutin, Kojic acid, nicotinamide, hydroquinone, resorcinol, 4-methoxyphenol, 4-ethoxyphenol and ascorbic acid from skin whitening Products by HPLC-UV

    USDA-ARS?s Scientific Manuscript database

    Development of an analytical method for the simultaneous determination of multifarious skin whitening agents will provide an efficient tool to analyze skin whitening cosmetics. An HPLC-UV method was developed for quantitative analysis of six commonly used whitening agents, a-arbutin, ß-arbutin, koji...

  12. Skin whitening and anti-corrugation activities of glycoprotein fractions from liquid extracts of boiled sea cucumber.

    PubMed

    Kim, So Jung; Park, So Yun; Hong, Sun-Mee; Kwon, Eun-Hye; Lee, Taek-Kyun

    2016-10-01

    To determine skin whitening and wrinkle improvement efficacy, glycoprotein fractions were extracted from liquid extracts of boiled sea cucumber and their effects on tyrosine and elastase inhibitory activities were assayed. Fractions above and below 50 kDa (>50 kDa and <50 kDa) were extracted via a series of steps involving: boiling, filtering, desalting and freeze drying. Cytotoxicity, skin whitening and wrinkle-removing effects of boiled liquid were determined. Our MTT data showed that neither glycoprotein fraction of boiled liquid induces cellular cytotoxicity up to a concentration of 10 mg/mL treatment of the mouse melanoma cell line, B16F10, with 10 mg/mL >50 kDa enhanced tyrosinase and elastase inhibitory activities by 50.84% and 28.78%, respectively. Correlations of the >50 kDa concentration with tyrosinase inhibitory (R2 = 0.968) and elastase inhibitory (R2 = 0.983) efficacy were significant. >50 kDa glycoprotein fraction isolated from liquid extracts of boiled sea cucumber, which can serve as a functional cosmetic ingredient for whitening and wrinkle improvement of skin. Copyright © 2016 Hainan Medical University. Production and hosting by Elsevier B.V. All rights reserved.

  13. Power and Socioscientific Issues: The Pedagogy of Mire's Critique of Skin Whitening Cosmeceuticals

    ERIC Educational Resources Information Center

    Blades, David

    2012-01-01

    In her article, "The Scientification of Skin Whitening and the Entrepreneurial University- Linked Corporate Scientific Officer," published in this issue, Amina Mire (2012) deconstructs the tacit investments implicit in such discourses of beauty, in particular those linked to cosmetic products that purport to fight the "war on aging" through the…

  14. In vitro Dermal Absorption of Hydroquinone: Protocol Validation and Applicability on Illegal Skin-Whitening Cosmetics.

    PubMed

    Desmedt, Bart; Ates, Gamze; Courselle, Patricia; De Beer, Jacques O; Rogiers, Vera; Hendrickx, Benoit; Deconinck, Eric; De Paepe, Kristien

    2016-01-01

    In Europe, hydroquinone is a forbidden cosmetic ingredient. It is, however, still abundantly used because of its effective skin-whitening properties. The question arises as to whether the quantities of hydroquinone used become systemically available and may cause damage to human health. Dermal absorption studies can provide this information. In the EU, dermal absorption has to be assessed in vitro since the Cosmetic Regulation 1223/2009/EC forbids the use of animals. To obtain human-relevant data, a Franz diffusion cell protocol was validated using human skin. The results obtained were comparable to those from a multicentre validation study. The protocol was applied to hydroquinone and the dermal absorption ranged between 31 and 44%, which is within the range of published in vivo human values. This shows that a well-validated in vitro dermal absorption study using human skin provides relevant human data. The validated protocol was used to determine the dermal absorption of illegal skin-whitening cosmetics containing hydroquinone. All samples gave high dermal absorption values, rendering them all unsafe for human health. These results add to our knowledge of illegal cosmetics on the EU market, namely that they exhibit a negative toxicological profile and are likely to induce health problems. © 2017 S. Karger AG, Basel.

  15. HPLC-UV Method for the Identification and Screening of Hydroquinone, Ethers of Hydroquinone and Corticosteroids Possibly Used as Skin-Whitening Agents in Illicit Cosmetic Products.

    PubMed

    Gimeno, Pascal; Maggio, Annie-Françoise; Bancilhon, Marjorie; Lassu, Nelly; Gornes, Hervé; Brenier, Charlotte; Lempereur, Laurent

    2016-03-01

    Corticosteroids, hydroquinone and its ethers are regulated in cosmetics by the Regulation 1223/2009. As corticosteroids are forbidden to be used in cosmetics and cannot be present as contaminants or impurities, an identification of one of these illicit compounds deliberately introduced in these types of cosmetics is enough for market survey control. In order to quickly identify skin-whitening agents present in illegal cosmetics, this article proposes an HPLC-UV method for the identification and screening of hydroquinone, 3 ethers of hydroquinone and 39 corticosteroids that may be found in skin-whitening products. Two elution gradients were developed to separate all compounds. The main solvent gradient (A) allows the separation of 39 compounds among the 43 compounds considered in 50 min. Limits of detection on skin-whitening cosmetics are given. For compounds not separated, a complementary gradient elution (B) using the same solvents is proposed. Between 2004 and 2009, a market survey on "skin-whitening cosmetic" was performed on 150 samples and highlights that more than half of the products tested do not comply with the Cosmetic Regulation 1223/2009 (amending the Council Directive 76/768/EEC). © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. A whitened face woman with nephrotic syndrome.

    PubMed

    Soo, Yannie Oi-Yan; Chow, Kai-Ming; Lam, Christopher Wai-Kei; Lai, Fernand Mac-Moune; Szeto, Cheuk-Chun; Chan, Michael Ho-Ming; Li, Philip Kam-Tao

    2003-01-01

    Skin whitening cream from developing countries is a recognized source of chronic mercury poisoning. The authors report on a 34-year-old Indonesian domestic helper who presented with nephrotic syndrome secondary to membranous nephropathy. It was subsequently found that she used a skin whitening cream regularly that was found to contain a mercury level of almost 2,000 times above the allowable limit. Her blood and urinary mercury levels were both grossly elevated. Her symptoms improved after she stopped using the cream. However, she returned to her home country before chelating therapy could be arranged. Because mercury-containing skin products are still widely available in developing countries, the use of these products should be considered a possible cause of membranous nephropathy in immigrants from those countries. Copyright 2003 by the National Kidney Foundation, Inc.

  17. Electro therapy facial and laser skin whitening: Clients' perspective.

    PubMed

    Lavanya, D; Manimaran, S; Bhagyalakshmi, K

    2018-01-01

    There are so many beauty salons in Metropolis who provide services to women exclusively [1]. These beauty salons depend mostly on electricity for their services to customers, without it there is no effective means of operation [2]. These beauty salons are definitely leading to women empowerment. The beauty salons are run by the women for women. Since they fall under the category of micro and small enterprises, these salons may avail so many financial and non- financial advantages from the Government of India. They also provide employment opportunities to the women employees. The development of such beauty salons rests on the clients' satisfaction on the provision of their services. Hence it is essential to measure the clients attitude towards the services offered by the beauty salons, especially electro therapy facial, laser skin whitening and laser hair removal treatments, which are coming under micro current treatment as a cosmetic tool.

  18. Whitening Effect of Black Tea Water Extract on Brown Guinea Pig Skin

    PubMed Central

    Choi, So-Young

    2011-01-01

    To evaluate the whitening effect of black tea water extract (BT), BT was topically applied to artificially hyperpigmented spots on the back skins of brown guinea-pigs (weight: 450~500 g) induced by 1,500 mJ/ cm2 of ultraviolet B (UVB) irradiation. The test compounds of 30 μl were applied twice a day, six days a week, for four weeks. The artificially hyperpigmented spots were divided into 5 groups: control (UVB + saline, C), vehicle control [UVB + propylene glycol: ethanol: water (5 : 3 : 2), VC], positive control (UVB + 2% hydroquinone, PC), experimental 1 (UVB + 1% BT), experimental 2 (UVB + 2% BT). After 4-week application, the spots were removed by biopsy punch under anesthetic condition and used as specimens for the histological examination. The total polyphenol and flavonoid contents of BT were 104 and 91 mg/g, respectively. The electron-donating ability of BT revealed a dose-dependent response, showing the excellent capacities of 86% at 800 μg/ml. The artificially hyperpigmented spots treated with the PC and BT were obviously lightened compared to the C and VC groups. At the fourth week, the melanin indices for the PC and BT groups were significantly lower (p < 0.00l) than those of the C and VC groups. In histological examination, PC and BT groups were significantly reduced in the melanin pigmentation, the proliferation of melanocytes and the synthesis of melanosomes compared to the C and VC groups. It is found that BT inhibits the proliferation of melanocytes and synthesis of melanosomes in vivo using brown guinea pigs, thereby showing a definite skin whitening effect. PMID:24278566

  19. Quantitative Determination of α-Arbutin, β-Arbutin, Kojic Acid, Nicotinamide, Hydroquinone, Resorcinol, 4-Methoxyphenol, 4-Ethoxyphenol, and Ascorbic Acid from Skin Whitening Products by HPLC-UV.

    PubMed

    Wang, Yan-Hong; Avonto, Cristina; Avula, Bharathi; Wang, Mei; Rua, Diego; Khan, Ikhlas A

    2015-01-01

    An HPLC-UV method was developed for the quantitative analysis of nine skin whitening agents in a single injection. These compounds are α-arbutin, β-arbutin, kojic acid, nicotinamide, resorcinol, ascorbic acid, hydroquinone, 4-methoxyphenol, and 4-ethoxyphenol. The separation was achieved on a reversed-phase C18 column within 30 min. The mobile phase was composed of water and methanol, both containing 0.1% acetic acid (v/v). The stability of the analytes was evaluated at different pH values between 2.3 and 7.6, and the extraction procedure was validated for different types of skin whitening product matrixes, which included two creams, a soap bar, and a capsule. The best solvent system for sample preparation was 20 mM NaH2PO4 containing 10% methanol at pH 2.3. The analytical method was validated for accuracy, precision, LOD, and LOQ. The developed HPLC-UV method was applied for the quantitation of the nine analytes in 59 skin whitening products including creams, lotions, sera, foams, gels, mask sheets, soap bars, tablets, and capsules.

  20. Skin whitening among Cameroonian female university students: knowledge, attitudes, practices and motivations.

    PubMed

    Kouotou, Emmanuel Armand; Nansseu, Jobert Richie N; Adegbidi, Hugues; Zoa Mebara, Theophane Christel Joel; Ndjitoyap Ndam, Elie Claude

    2017-04-17

    Lack of data on skin whitening (SW) among Cameroonian female university students prompted us to undertake the present study which aimed at assessing the knowledge, attitudes, practices and motivations of female university students vis-a-vis SW. This was a cross-sectional study conducted from January to April 2013 in 4 university campuses of Yaoundé, Cameroon. Any female student regularly registered in one of the study sites, who was present at the campus when the investigator visited and volunteered to participate in the study was enrolled. Overall, we recruited 620 female students, their ages ranging from 16 to 46 years with a mean of 21.3 ± 2.9 years. Only 87 participants (14%) found that SW was a good practice. One hundred and sixty nine respondents (27.3%) were currently practicing SW with no age difference when compared to their counterparts (p = 0.09). The desire to have a uniform body skin color was the prevailing reason motivating the practice of SW (39.1%), followed by the need to have a soft skin (29%). Assessment of levels of knowledge regarding advantages of the black skin and deleterious effects of SW showed excellent scores (≥75% of good answers) only in 6.1 and 0.5% of cases respectively, with no difference between those practicing SW or not (all p values > 0.05). The practice of SW is common among Cameroonian female university students who should therefore be educated on the advantages of the black skin and the harmful effects of SW.

  1. Whitening effect of salicylic acid peels in Asian patients.

    PubMed

    Ahn, Hyo Hyun; Kim, Il-hwan

    2006-03-01

    Patients with skin of color demand treatment modality suitable for their skin. Salicylic acid peel has effectiveness for both of acne and postinflammatory hyperpigmentation that are common in patients with skin of color. To assess the whitening effect of salicylic acid peels in Asian patients with acne objectively by the colorimetric method. Twenty-four healthy adult patients with acne participated voluntarily in the study. Any other systemic and topical acne treatments were prohibited. They had undergone full-face peels with 30% salicylic acid in absolute ethanol bi-weekly for 3 months. Colorimetric changes of the face were recorded with reflectance spectrophotometer. Paired comparisons with pretreatment CIE L*a*b* showed abrupt descent of L* value after first peel (p=.0286). Then there was continued increase of mean L* value, even though the final L* value did not reach a statistically significant level. The mean a* value decreased continually, and the a* values recorded after the second, third, fourth, fifth, and final peel showed significantly lowered levels (p=.0027, .0005, <.0001, <.0001, <.0001). Salicylic acid peels are beneficial in whitening the face of Asian patients with acne. The whitening effect would be an important factor in choosing the superficial peeling agent for them.

  2. Whitening Efficacy of Whitening Mouth Rinses Used Alone or in Conjunction With Carbamide Peroxide Home Whitening.

    PubMed

    Oliveira, Jbs; Sarlo, R S; Bresciani, E; Caneppele, Tmf

    The aim of this study was to compare the effectiveness of whitening mouth rinses on teeth previously whitened or not, exposed to food dyes. One hundred twenty enamel-dentin specimens, 3 mm in diameter, were obtained from bovine incisors. The specimens were stained for 14 days in staining broth. After staining, the initial color reading was performed via a spectrophotometer CM-2600d (Konica Minolta). Half of specimens were submitted to whitening (10% carbamide peroxide [CP]) for 14 days. They were then divided into three groups and were submitted to cycles of staining (five minutes) and mouth rinses (two minutes) for 12 weeks, with the following: CP-LI, Listerine Whitening; CP-PL, Plax Whitening; CP-BP, bromelain + papain; CP-DW, deionized water. LI, PL, BP, and DW groups were submitted to the same cited cycles but with no prior bleaching. The color measurements were performed after four, eight, and 12 weeks of treatment with mouth rinses. Data were submitted to repeated measures analysis of variance (ANOVA) and Tukey's test for multiple comparisons, with significance level at 5%. The results showed that the CP-LI, CP-PL, LI, and PL groups had greater color change than did the others. The CP-BP and BP groups were similar to CP-DW and DW. We therefore conclude that Listerine Whitening mouth rinse presented the highest bleaching effect, followed by Plax Whitening mouth rinse. Both maintained CP bleaching effect after 12 weeks of dye-rinse cycles. However, none of these rinses were able to produce whitening similar to CP. Bromelain- and papain-containing mouth rinses did not show bleaching effect, being similar to the control groups.

  3. Application of solid phase extraction on multiwalled carbon nanotubes of some heavy metal ions to analysis of skin whitening cosmetics using ICP-AES.

    PubMed

    Alqadami, Ayoub A; Abdalla, Mohammad Abulhassan; AlOthman, Zeid A; Omer, Kamal

    2013-01-14

    A novel and highly sensitive method for the determination of some heavy metals in skin whitening cosmetics creams using multiwalled carbon nanotubes MWCNTs as solid phase extraction sorbent for the preconcentration of these heavy metals prior to their determination by inductively coupled plasma atomic emission spectrometry is described. Different practical parameters have been thoroughly investigated and the optimum experimental conditions were employed. The developed method was then applied for the determination of arsenic, bismuth, cadmium, mercury, lead and titanium in samples of skin whitening cosmetics. The detection limits under these conditions for As, Bi, Cd, Pb, Hg and Ti were 2.4, 4.08, 0.3, 2.1, 1.8, and 1.8 ng·mL-1, respectively. The relative standard deviations (RSDs) were found to be less than 2.0%. For validation, a certified reference material of NIST SRM 1570a spinach leaves was analyzed and the determined values were in good agreement with the certified values. The recoveries for spiked samples were found to be in the range of 89.6-104.4%.

  4. Application of Solid Phase Extraction on Multiwalled Carbon Nanotubes of Some Heavy Metal Ions to Analysis of Skin Whitening Cosmetics Using ICP-AES

    PubMed Central

    ALqadami, Ayoub A.; Abdalla, Mohammad Abulhassan; ALOthman, Zeid A.; Omer, Kamal

    2013-01-01

    A novel and highly sensitive method for the determination of some heavy metals in skin whitening cosmetics creams using multiwalled carbon nanotubes MWCNTs as solid phase extraction sorbent for the preconcentration of these heavy metals prior to their determination by inductively coupled plasma atomic emission spectrometry is described. Different practical parameters have been thoroughly investigated and the optimum experimental conditions were employed. The developed method was then applied for the determination of arsenic, bismuth, cadmium, mercury, lead and titanium in samples of skin whitening cosmetics. The detection limits under these conditions for As, Bi, Cd, Pb, Hg and Ti were 2.4, 4.08, 0.3, 2.1, 1.8, and 1.8 ng·mL−1, respectively. The relative standard deviations (RSDs) were found to be less than 2.0%. For validation, a certified reference material of NIST SRM 1570a spinach leaves was analyzed and the determined values were in good agreement with the certified values. The recoveries for spiked samples were found to be in the range of 89.6–104.4%. PMID:23343988

  5. Present and future technologies of tooth whitening.

    PubMed

    Viscio, D; Gaffar, A; Fakhry-Smith, S; Xu, T

    2000-01-01

    Dental stains can be broadly classified as intrinsic or extrinsic. Intrinsic stains are a result of defects in tooth development, fluorosis, or acquired through the use of tetracycline. Extrinsic stains are localized mainly in the pellicle and are generated by the reaction between sugars and amino acids or acquired from the retention of exogenous chromophores in the pellicle. Three clinical methods are currently used for measuring stain removal and tooth whitening in the development of new whitening technologies: Lobene Stain Index, Shade Guide Color Change, and Minolta ChromaMeter. Professional tooth whitening products rely on proven technologies--35% hydrogen peroxide for in-office power bleaching or 10% to 15% carbamide peroxide for at-home bleaching--to reduce intrinsic stain and change the inherent tooth color. Over-the-counter tooth whitening products use a combination of surfactants, abrasives, anticalculus agents, and low levels of hydrogen peroxide to reduce extrinsic stain and help maintain tooth whiteness after professional treatment. Future technologies for whitening teeth could involve the use of activating agents to enhance the performance of hydrogen peroxide and natural enzymes.

  6. Dental whitening--revisiting the myths.

    PubMed

    Perdigão, Jorge

    2010-01-01

    The popularity of dental bleaching has increased with the introduction of at-home whitening. Currently available whitening methods include those prescribed by a dental professional for use at home, those applied by the professional in the dental office, a combination of the two, or systems available over the counter. This article reviews the effect, efficacy, and safety of bleaching techniques and materials. Most whitening techniques are considered effective and safe when carried out under the supervision of a dental professional. This article also compares the efficacy and safety of some of the most popular bleaching techniques, including at-home whitening with carbamide peroxide, over-the-counter (OTC) systems, and in-office whitening. Some of these whitening techniques are illustrated in this article.

  7. Tooth Whitening: What We Now Know

    PubMed Central

    Carey, Clifton M.

    2014-01-01

    Declarative Title Current research about tooth whitening shows that it is safe and effective when manufacturer’s protocol is followed, yet there are risks of which the profession and users should be aware. This update provides a summary of current research and assessment of the safety and efficacy of tooth whitening regimens. Background Tooth whitening has become one of the most frequently requested dental procedures by the public. The public has come to demand whiter, more perfect smiles and in response many choices for tooth whitening have been made available. These include home-based products such as toothpastes, gels, and films, as well as in-office based systems where products containing highly concentrated bleaching agents are applied under professional supervision. The profession and public have been aware of certain risks related to tooth whitening such as increased tooth sensitivity and gingival irritation. New research has shown that there are other risks such as tooth surface roughening and softening, increased potential for demineralization, degradation of dental restorations, and unacceptable color change of dental restorations. The new research is also focused on optimizing whitening procedures to reduce tooth sensitivity and to increase the persistence of the whitening. Methods Current reports in the literature are reviewed that are related to the use of peroxide based whitening methods. These reports include in vitro studies for method optimization and mechanism as well as clinical studies on effects of various whitening regimens. Conclusions When manufacturer’s instructions are followed, hydrogen peroxide and carbamide peroxide based tooth whitening is safe and effective. Patients should be informed of the risks associated with tooth whitening and instructed on identification of adverse occurrences so that they may seek professional help asneeded. PMID:24929591

  8. Efficacy of do-it-yourself whitening as compared to conventional tooth whitening modalities: an in vitro study.

    PubMed

    Kwon, S R; Meharry, M; Oyoyo, U; Li, Y

    2015-01-01

    To evaluate the efficacy of do-it-yourself (DIY) whitening as compared to conventional tooth whitening modalities using different shade assessment tools. Extracted human molars (120) were randomly distributed to six groups (n=20). Whitening was performed according to manufacturer's directions for over-the-counter, dentist-dispensed for home use, and in-office whitening. DIY whitening consisted of a strawberry and baking soda mix. Additionally, negative and positive controls were used. Two evaluators used the Vita Classical (VC) and Vita Bleachedguide 3D-Master with interpolated numbers (BGi) for visual assessment at baseline and one-week, one-month, and three-month postwhitening. Instrumental measurements were performed with a spectrophotometer. Kruskal-Wallis procedure was used to assess color changes among groups and intraclass correlation (ICC) to evaluate agreement between evaluators. DIY exhibited lower color change (ΔSGUVC, ΔSGUBGi, ΔE*, where SGU = shade guide unit and E = overall color change) compared to other whitening groups at all time points (p<0.05). ICC demonstrated very good agreement between evaluators with VC and BGi at each time point. Both shade guides were related with each other and strongly related to instrumental measurements (p<0.05). DIY whitening was the least effective whitening modality. Both VC and BGi are related with each other and have good correlation with instrumental measurements.

  9. Anti-skin-aging benefits of exopolymers from Aureobasidium pullulans SM2001.

    PubMed

    Kim, Kyung Hu; Park, Soo Jin; Lee, Ji Eun; Lee, Young Joon; Song, Chang Hyun; Choi, Seong Hun; Ku, Sae Kwang; Kang, Su Jin

    2014-01-01

    There have been many attempts to search for affordable and effective functional cosmetic ingredients, especially from natural sources. As research into developing a functional cosmetic ingredient, we investigated whether exopolymers from Aureobasidium pullulans SM2001 (E-AP-SM2001) exert antioxidant, antiwrinkle, whitening, and skin moisturizing effects. Antioxidant effects of E-AP-SM2001 were determined by measuring free radical scavenging capacity and superoxide dismutase (SOD)-like activity. Antiwrinkle effects were assessed through the inhibition of hyaluronidase, elastase, collagenase, and matrix metalloproteinase (MMP)-1. Whitening effects were measured by tyrosinase inhibition assay, and by melanin formation test in B16/F10 melanoma cells. Skin moisturizing effects were detected by mouse skin water content test. E-AP-SM2001 showed potent DPPH radical scavenging activity and SOD-like effects. Additionally, hyaluronidase, elastase, collagenase, and MMP-1 activities were significantly inhibited by E-AP-SM2001. We also observed that E-AP-SM2001 effectively reduced melanin production by B16/F10 melanoma cells and mushroom tyrosinase activities. Furthermore, significant increases in skin water content were detected in E-AP-SM2001- treated mouse skin, as compared with vehicle-treated control skin. Notably, a mask pack containing E-AP-SM2001 showed a >twofold more extensive moisturizing effect compared with one containing Saccharomycopsis ferment filtrate. Our results suggest that E-AP-SM2001 has adequate antiaging, antiwrinkle, and whitening benefits and skin moisturizing effect. These effects involve reducing hyaluronidase, elastase, collagenase, and MMP-1 activities, as well as inhibition of melanin production and tyrosinase activities. Therefore, the antioxidant E-AP-SM2001 may serve as a predictable functional ingredient.

  10. Age estimation using level of eyebrow and eyelash whitening

    PubMed Central

    Kantarcı, Feride Aylin; Kantarcı, Muhammed Nabi; Bilgi, Sefer

    2014-01-01

    Background The aim of this study was to determine whether eyebrow and eyelash whitening is an effective parameter in age estimation. Material/Methods We evaluated 1545 patients. Age groups were 1–10, 11–20, 21–30, 31–40, 41–50, 51–60, 61–70, 71–80, and 81–90 years. Level of whitening was categorized as level 0: no whitening, level 1: 1–3 strands, level 2: 3–10 strands, level 3: 10 strands–2/3 whitening, level 4: >3/4 whitening. Results Mean age was 42.39±20.01. While there was no eyebrow whitening in 87% of the subjects, level 4 whitening of eyebrows was observed in 0,8% of the subjects. There was no eyelash whitening in 97,7% of the subjects and no level 4 eyelash whitening was detected in any subject. Men had significantly more level 1, 2, 3, and 4 eyebrow whitening compared with women. There was no gender difference in terms of eyelash whitening level. There was no eyebrow and eyelash whitening in subjects age 1–40 years; whitening began in the 41–50 years age group and increased with age in other groups. Mean age was 39.59±19.63 years in subjects with no eyebrow whitening; 59 years in level 1, 61 years in level 2, 63 years in level 3, and 69 years in level 4 eyebrow whitening. Mean age was 41.85±19.87 in subjects with no eyelash whitening; and 63.57±10.75 in those with whitening. Conclusions Particularly after 41–50 years of age, level of eyebrow and eyelash whitening may be among a useful age estimation parameter. PMID:24448310

  11. Evaluating the Whitening and Microstructural Effects of a Novel Whitening Strip on Porcelain and Composite Dental Materials

    PubMed Central

    Takesh, Thair; Sargsyan, Anik; Lee, Matthew; Anbarani, Afarin; Ho, Jessica; Wilder-Smith, Petra

    2017-01-01

    Aims The aim of this project was to evaluate the effects of 2 different whitening strips on color, microstructure and roughness of tea stained porcelain and composite surfaces. Methods 54 porcelain and 72 composite chips served as samples for timed application of over-the-counter (OTC) test or control dental whitening strips. Chips were divided randomly into three groups of 18 porcelain and 24 composite chips each. Of these groups, 1 porcelain and 1 composite set served as controls. The remaining 2 groups were randomized to treatment with either Oral Essentials® Whitening Strips or Crest® 3D White Whitestrips™. Sample surface structure was examined by light microscopy, profilometry and Scanning Electron Microscopy (SEM). Additionally, a reflectance spectrophotometer was used to assess color changes in the porcelain and composite samples over 24 hours of whitening. Data points were analyzed at each time point using ANOVA. Results In the light microscopy and SEM images, no discrete physical defects were observed in any of the samples at any time points. However, high-resolution SEM images showed an appearance of increased surface roughness in all composite samples. Using profilometry, significantly increased post-whitening roughness was documented in the composite samples exposed to the control bleaching strips. Composite samples underwent a significant and equivalent shift in color following exposure to Crest® 3D White Whitestrips™ and Oral Essentials® Whitening Strips. Conclusions A novel commercial tooth whitening strip demonstrated a comparable beaching effect to a widely used OTC whitening strip. Neither whitening strip caused physical defects in the sample surfaces. However, the control strip caused roughening of the composite samples whereas the test strip did not. PMID:29226023

  12. Physiological activity of irradiated green tea polyphenol on the human skin.

    PubMed

    An, Bong-Jeun; Kwak, Jae-Hoon; Son, Jun-Ho; Park, Jung-Mi; Lee, Jin-Young; Park, Tae Soon; Kim, So-Yeun; Kim, Yeoung-Sun; Jo, Cheorun; Byun, Myung-Woo

    2005-01-01

    Physiological activity of irradiated green tea polyphenol on the human skin was investigated for further industrial application. The green tea polyphenol was separated and irradiated at 40 kGy by y-ray. For an anti-wrinkle effect, the collagenase inhibition effect was higher in the irradiated sample (65.3%) than that of the non-irradiated control (56.8%) at 200 ppm of the concentration (p < 0.05). Collagen biosynthesis rates using a human fibroblast were 19.4% and 16.3% in the irradiated and the non-irradiated polyphenols, respectively. The tyrosinase inhibition effect, which is related to the skin-whitening effect, showed a 45.2% and 42.9% in the irradiated and the non-irradiated polyphenols, respectively, at a 100 ppm level. A higher than 90% growth inhibition on skin cancer cells (SK-MEL-2 and G361) was demonstrated in both the irradiated and the non-irradiated polyphenols. Thus, the irradiation of green tea polyphenol did not change and even increased its anti-wrinkle, skin-whitening and anticancer effects on the human skin. The results indicated that irradiated green tea polyphenol can be used as a natural ingredient with excellent physiological functions for the human skin through cosmetic or food composition.

  13. Use of quantitative light-induced fluorescence to monitor tooth whitening

    NASA Astrophysics Data System (ADS)

    Amaechi, Bennett T.; Higham, Susan M.

    2001-04-01

    The changing of tooth shade by whitening agents occurs gradually. Apart from being subjective and affected by the conditions of the surroundings, visual observation cannot detect a very slight change in tooth color. An electronic method, which can communicate the color change quantitatively, would be more reliable. Quantitative Light- induced Fluorescence (QLF) was developed to detect and assess dental caries based on the phenomenon of change of autofluorescence of a tooth by demineralization. However, stains on the tooth surface exhibit the same phenomenon, and therefore QLF can be used to measure the percentage fluorescence change of stained enamel with respect to surrounding unstained enamel. The present study described a technique of assessing the effect of a tooth-whitening agent using QLF. This was demonstrated in two experiments in which either wholly or partially stained teeth were whitened by intermittent immersion in sodium hypochlorite. Following each immersion, the integrated fluorescence change due to the stain was quantified using QLF. In either situation, the value of (Delta) Q decreased linearly as the tooth regained its natural shade. It was concluded that gradual changing of the shade of discolored teeth by a whitening agent could be quantified using QLF.

  14. The current status of vital tooth whitening techniques.

    PubMed

    Blankenau, R; Goldstein, R E; Haywood, V B

    1999-08-01

    Tooth whitening of vital teeth continues to have a major impact on the practice of dentistry. The growing public interest in having whiter, brighter teeth is clearly evident in the advertisements from toothpaste manufacturers on "whitening" formulations of their products and by the number of individuals seeking whitening procedures from their dentists. In addition, new over-the-counter whitening products continue to emerge in a marketplace that cannot seem to get teeth white enough, bright enough, fast enough. What new products and procedures have evolved over the past decade to whiten teeth? Are they better, safer, faster, and more effective now? Are dentists meeting public demand for whiter teeth and is this quest having a positive or negative impact on the practice of dentistry or the patient's dental health? I posed these questions to a group of experts on whitening procedures to get their opinions and recommendations.

  15. Complications of cosmetic eye whitening.

    PubMed

    Tran, Ann Q; Hoppener, Catherine; Venkateswaran, Nandini; Choi, Daniel S; Lee, Wendy W

    2017-09-01

    Introduced in 2008 and subsequently popularized in South Korea, cosmetic eye whitening has been offered as a treatment of chronic conjunctival hyperemia. Patients undergo conjunctivectomy with topical mitomycin C (MMC) 0.02% application to achieve a whitened appearance from bleaching of avascular sclera. Much speculation has arisen from this procedure given the limited available evidence on its efficacy and safety. A literature search was performed to review common complications of cosmetic eye whitening, including chronic conjunctival epithelial defects, scleral thinning, avascular zones in the sclera, dry eye syndrome, and diplopia requiring strabismus surgery. Informing the general public of the risks of this procedure is of great importance for dermatologists and other cosmetic surgeons.

  16. A comparative clinical study evaluating stain removal efficacy of a new sensitivity whitening dentifrice compared to commercially available whitening dentifrices.

    PubMed

    Hughes, Nathan; Maggio, Brenda; Sufi, Farzana; Mason, Stephen; Kleber, Carl J

    2009-01-01

    To assess the extrinsic stain removal efficacy of a new sensitivity dentifrice containing sodium tripolyphosphate (STP) to marketed whitening toothpastes after six weeks of product use. This was a single-center, double-blind, stratified, six-week clinical study comparing the reduction in stain area and intensity of Sensodyne Extra Whitening to Crest Maximum Strength Sensitivity Protection Whitening plus Scope and Colgate Tartar Control Plus Whitening Mint dentifrice, as measured by MacPherson's Modification of the Lobene Stain Index (MMLSI) in a forced stain model. Two-hundred and ninety-five subjects completed the study. Tooth stain MMSLI scores showed significant differences between Sensodyne and Crest dentifrices in favor of Sensodyne for all surface sites (p = 0.014), and individually for facial (p = 0.023), lingual (p = 0.027), and interproximal (p = 0.014) surfaces. No significant statistical differences between Sensodyne and Colgate dentifrices were observed for any of the surfaces. Results from this stain removal clinical study demonstrate significant extrinsic stain removal efficacy for all dentifrices relative to baseline. Significant differences between the two marketed sensitivity whitening dentifrices were demonstrated in favor of the new Sensodyne Sensitivity Whitening dentifrice.

  17. Efficacy of mouth rinses and toothpaste on tooth whitening.

    PubMed

    Torres, C R G; Perote, L C C C; Gutierrez, N C; Pucci, C R; Borges, A B

    2013-01-01

    People increasingly desire tooth whitening. Considering the wide range of whitening products on the market, this study evaluated the efficacy of whitening toothpastes and mouth rinses compared with the 10% carbamide peroxide (CP) whitening gel. We obtained 120 cylindrical specimens from bovine teeth, which were darkened for 24 hours in a coffee solution. The color measurement was performed by a spectrophotometer using the CIE L*a*b* system, and specimens were divided into six groups according to the use of the following agents: group 1, conventional fluoridated toothpaste; group 2, Close Up White Now; group 3, Listerine Whitening; group 4, Colgate Plax Whitening; group 5, experimental mouth rinse with Plasdone; and group 6, 10% CP Whiteness Perfect. After the simulation of 12 weeks of treatment for groups 1 to 5 and 14 days of treatment for group 6, the specimens were subjected to a new color reading. Data were subjected to one-way analysis of variance (α=0.05), which showed significant differences among groups after 12 weeks for ΔE (p=0.001). Results of the Tukey test revealed that groups 3, 4, and 6 presented significantly higher color alteration than groups 1, 2, and 5. The whitening toothpaste Close Up White Now and the experimental mouth rinse with Plasdone showed similar color alteration as conventional toothpaste after a 12-week treatment simulation. These groups presented significantly lower color alteration compared with whitening mouth rinses Listerine and Colgate Plax Whitening, which showed similar results to those observed after 14 days of bleaching with 10% CP treatment.

  18. Antimelanogenic Efficacy of Melasolv (3,4,5-Trimethoxycinnamate Thymol Ester) in Melanocytes and Three-Dimensional Human Skin Equivalent.

    PubMed

    Lee, John Hwan; Lee, Eun-Soo; Bae, Il-Hong; Hwang, Jeong-Ah; Kim, Se-Hwa; Kim, Dae-Yong; Park, Nok-Hyun; Rho, Ho Sik; Kim, Yong Jin; Oh, Seong-Geun; Lee, Chang Seok

    2017-01-01

    Excessive melanogenesis often causes unaesthetic hyperpigmentation. In a previous report, our group introduced a newly synthesized depigmentary agent, Melasolv™ (3,4,5-trimethoxycinnamate thymol ester). In this study, we demonstrated the significant whitening efficacy of Melasolv using various melanocytes and human skin equivalents as in vitro experimental systems. The depigmentary effect of Melasolv was tested in melan-a cells (immortalized normal murine melanocytes), α-melanocyte-stimulating hormone (α-MSH)-stimulated B16 murine melanoma cells, primary normal human melanocytes (NHMs), and human skin equivalent (MelanoDerm). The whitening efficacy of Melasolv was further demonstrated by photography, time-lapse microscopy, Fontana-Masson (F&M) staining, and 2-photon microscopy. Melasolv significantly inhibited melanogenesis in the melan-a and α-MSH-stimulated B16 cells. In human systems, Melasolv also clearly showed a whitening effect in NHMs and human skin equivalent, reflecting a decrease in melanin content. F&M staining and 2-photon microscopy revealed that Melasolv suppressed melanin transfer into multiple epidermal layers from melanocytes as well as melanin synthesis in human skin equivalent. Our study showed that Melasolv clearly exerts a whitening effect on various melanocytes and human skin equivalent. These results suggest the possibility that Melasolv can be used as a depigmentary agent to treat pigmentary disorders as well as an active ingredient in cosmetics to increase whitening efficacy. © 2017 S. Karger AG, Basel.

  19. Effects of a Novel Whitening Formulation on Dental Enamel

    PubMed Central

    Takesh, Thair; Sargsyan, Anik; Anbarani, Afarin; Ho, Jessica; Wilder-Smith, Petra

    2017-01-01

    Objective The goal of this study was to evaluate the enamel whitening effects of 2 new test formulations, one of which was a rinse, and the other a whitening strip. Materials and Methods Forty enamel chips were prepared from 20 healthy extracted teeth (2 from each tooth). After pre-staining and colorimetry to measure L* and b* values, 20 matched samples were immersed in either test or control rinses, and then colorimetry was performed again after 1 hr, 2 hr, 3 hr, 6 hr, 12 hr, 24 hr and 48 hrs (Each hour equates to one month of clinical use at the recommended dosage of 1 minute exposure 2 times a day). The remaining 20 matched samples were exposed to the test or control whitening strips and colorimetry was performed every 30 minutes for a total of 10 treatments. Results Overall, the whitening performance of test and control strips was similar. The test and control rinses had a similar lightening effect over the first 3 hours (equivalent to 3 months of clinical use). Subsequently, the control rinse continued to lighten samples, whereas the test rinse had little further effect. Conclusion Test and control-whitening strips showed similar effects; over time whitening strips showed a greater lightening effect than whitening rinses. PMID:28706755

  20. Effects of a Novel Whitening Formulation on Dental Enamel.

    PubMed

    Takesh, Thair; Sargsyan, Anik; Anbarani, Afarin; Ho, Jessica; Wilder-Smith, Petra

    2017-04-01

    The goal of this study was to evaluate the enamel whitening effects of 2 new test formulations, one of which was a rinse, and the other a whitening strip. Forty enamel chips were prepared from 20 healthy extracted teeth (2 from each tooth). After pre-staining and colorimetry to measure L* and b* values, 20 matched samples were immersed in either test or control rinses, and then colorimetry was performed again after 1 hr, 2 hr, 3 hr, 6 hr, 12 hr, 24 hr and 48 hrs (Each hour equates to one month of clinical use at the recommended dosage of 1 minute exposure 2 times a day). The remaining 20 matched samples were exposed to the test or control whitening strips and colorimetry was performed every 30 minutes for a total of 10 treatments. Overall, the whitening performance of test and control strips was similar. The test and control rinses had a similar lightening effect over the first 3 hours (equivalent to 3 months of clinical use). Subsequently, the control rinse continued to lighten samples, whereas the test rinse had little further effect. Test and control-whitening strips showed similar effects; over time whitening strips showed a greater lightening effect than whitening rinses.

  1. Necrotizing scleritis as a complication of cosmetic eye whitening procedure.

    PubMed

    Leung, Theresa G; Dunn, James P; Akpek, Esen K; Thorne, Jennifer E

    2013-02-22

    We report necrotizing scleritis as a serious complication of a cosmetic eye whitening procedure that involves the use of intraoperative and postoperative topical mitomycin C. This is a single case report. A 59-year-old Caucasian male with a history of blepharitis status post uncomplicated LASIK refractive surgery reported chronic conjunctival hyperemia for 15 years prior to undergoing a cosmetic eye whitening procedure. He presented to our clinic 12 months after the cosmetic eye whitening procedure with progressive bilateral necrotizing scleritis and scleral calcification. Chronic conjunctival hyperemia may prompt patients to seek surgical correction with cosmetic eye whitening procedures. However, conjunctival hyperemia secondary to tear deficiency and evaporative dry eye may predispose to poor wound healing. Serious complications including necrotizing scleritis may result from cosmetic eye whitening procedures and the use of topical mitomycin C.

  2. Necrotizing scleritis as a complication of cosmetic eye whitening procedure

    PubMed Central

    2013-01-01

    Background We report necrotizing scleritis as a serious complication of a cosmetic eye whitening procedure that involves the use of intraoperative and postoperative topical mitomycin C. Findings This is a single case report. A 59-year-old Caucasian male with a history of blepharitis status post uncomplicated LASIK refractive surgery reported chronic conjunctival hyperemia for 15 years prior to undergoing a cosmetic eye whitening procedure. He presented to our clinic 12 months after the cosmetic eye whitening procedure with progressive bilateral necrotizing scleritis and scleral calcification. Conclusions Chronic conjunctival hyperemia may prompt patients to seek surgical correction with cosmetic eye whitening procedures. However, conjunctival hyperemia secondary to tear deficiency and evaporative dry eye may predispose to poor wound healing. Serious complications including necrotizing scleritis may result from cosmetic eye whitening procedures and the use of topical mitomycin C. PMID:23514228

  3. Erosion Potential of Tooth Whitening Regimens as Evaluated with Polarized Light Microscopy.

    PubMed

    Brambert, Patrick; Qian, Fang; Kwon, So Ran

    2015-11-01

    Tooth whitening is a widely utilized esthetic treatment in dentistry. With increased access to over-the-counter (OTC) systems concerns have been raised as to potential adverse effects associated with overuse of whitening materials. Therefore, this study aimed to evaluate enamel erosion due to different whitening regimens when used in excess of recommended guidelines. Extracted human teeth (n = 66) were randomly divided into 11 groups (n = 6/group). Specimens were exposed to OTC products: Crest Whitestrips and 5-minute natural white and a do-it-yourself (DIY) strawberry whitening recipe. Within each regimen, groups were further divided per exposure time: specimens receiving the recommended product dosage; 5 times the recommended dosage; and 10 times the recommended dosage. Negative and positive controls were treated with grade 3 water and 1.0% citric acid, respectively. Specimens were nail-varnished to limit application to a 1 × 4 mm window. Following treatment, specimens were sectioned and erosion (drop in μm) measured using polarized light microscopy. Two-sample t-test was used to detect difference in amount of enamel erosion between negative and positive groups, while one-way analysis of variance (ANOVA), followed by post hoc Dunnett's test was used to detect difference between set of treatment groups and negative control groups or among all experimental groups. There was significant difference in mean amount of enamel erosion (p < 0.0001). Mean enamel erosion for positive control group was significantly greater than that for negative control group (23.50 vs 2.65 μm). There was significant effect for type of treatments on enamel erosion [F(9,50) = 25.19; p < 0.0001]. There was no significant difference between the negative control and each of treatment groups (p > 0.05 for all instances), except for Natural White_10 times treatment group (p < 0.0001) that was significantly greater than the negative control group (14.82 vs 2.65 μm). Caution is advised when

  4. In vitro study on tooth enamel lesions related to whitening dentifrice.

    PubMed

    de Araújo, Danilo Barral; Silva, Luciana Rodrigues; Campos, Elisângela de Jesus; Correia de Araújo, Roberto Paulo

    2011-01-01

    The tooth whitening substances for extrinsic use that are available in Brazil contain hydrogen peroxide or carbamide peroxide. Several studies have attributed the appearance of lesions in the enamel morphology, including hypersensitivity, to these substances. Such lesions justify fluoride therapy and application of infrared lasers, among other procedures. However, there is no consensus among researchers regarding the relevance of the severity of lesions detected on the tooth surface. The present study was carried out with an aim of evaluating in vitro the effects of the hydrogen peroxide, carbamide peroxide and sodium bicarbonate contained in dentifrice formulations, on human tooth enamel. After darkening process in laboratory, human premolars were brushed using dentifrice containing the two whitening substances (Rembrandt - carbamide peroxide and Mentadent - hydrogen peroxide) and the abrasive product (Colgate - sodium bicarbonate). The degree of specimen staining before and after this procedure was determined using spectrophotometry. Scanning electron microscopy (SEM) was used to obtain images, which were analyzed to show the nature of the lesions that appeared on the enamel surface. The effectiveness of the whitening caused by hydrogen peroxide and carbamide peroxide and the abrasion caused by bicarbonate were confirmed, given that the treated test pieces returned to their original coloration. Based on SEM, evaluation of the enamel surfaces subjected to the test products showed that different types of morphologic lesions of varying severity appeared. Whitening dentifrice containing hydrogen peroxide and carbamide peroxide produced lesions on the enamel surface such that the greatest sequelae were associated with exposure to hydrogen peroxide.

  5. Effect of at-home whitening strips on the surface roughness and color of a composite and an ormocer restorative material.

    PubMed

    Gurbuz, Ayhan; Ozkan, Pelin; Yilmaz, Kerem; Yilmaz, Burak; Durkan, Rukiye

    2013-01-01

    became brighter after whitening. The behavior of the materials in the yellow/blue axis was opposite to each other after whitening. Each material had clinically unacceptable color change after whitening (ΔE > 5.5); however, the magnitude of the color change of materials was similar (p > 0.05). According to the results of this study, with the use of materials tested, patients should be advised that existing composite restorations may bleach along with the natural teeth, and replacement of these restorations after whitening may not be required. © 2012 by the American College of Prosthodontists.

  6. 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.

  7. Efficacy of whitening oral rinses and dentifrices on color stability of bleached teeth

    PubMed Central

    Karadas, Muhammet

    2015-01-01

    Abstract Objective: This study aimed to evaluate the effect of whitening toothpastes and mouthrinses on the color stability of teeth bleached with 16% carbamide peroxide (CP) after immersion in coffee solution. Materials and methods: Specimens obtained from bovine incisors were bleached with 16% CP for 14 days. After bleaching, the specimens were stained in coffee solution for 24 h and randomly divided into eight groups according to the following products (n = 10): distilled water (control group, DW), Scope White mouthrinse (SW), Crest 3D White mouthrinse (CWR), Crest 3D White toothpaste (CWT), Crest 3D White toothpaste and Crest 3D White mouthrinse (CWT + CWR), Listerine Whitening toothpaste (LWT), Listerine Whitening mouthrinse (LWR), and Listerine Whitening mouthrinse and Listerine Whitening toothpaste (LWR + LWT). Color measurements were conducted using a spectrophotometer. The data were assessed by analysis of variance for repeated measures and Tukey’s multiple comparison test (p < 0.05). Results: Immersion in coffee solution after bleaching caused perceptible staining on tooth specimens (ΔE > 3.46). The whitening effect of CWR on teeth stained after bleaching was significantly greater than that in the other groups (p < 0.001). Tooth whitening (ΔE) in each group showed no significant difference from 6 to 12 weeks (p > 0.05). The combination of mouthrinse and toothpaste did not increase the degree of tooth whitening. Conclusion: Whitening mouthrinse and toothpaste had similar effects on the control group in terms of whitening of teeth stained after bleaching. Nevertheless, Crest 3D White mouthrinse produced the greatest recovery whitening effect among all the products tested. PMID:28642898

  8. Automated detection of retinal whitening in malarial retinopathy

    NASA Astrophysics Data System (ADS)

    Joshi, V.; Agurto, C.; Barriga, S.; Nemeth, S.; Soliz, P.; MacCormick, I.; Taylor, T.; Lewallen, S.; Harding, S.

    2016-03-01

    Cerebral malaria (CM) is a severe neurological complication associated with malarial infection. Malaria affects approximately 200 million people worldwide, and claims 600,000 lives annually, 75% of whom are African children under five years of age. Because most of these mortalities are caused by the high incidence of CM misdiagnosis, there is a need for an accurate diagnostic to confirm the presence of CM. The retinal lesions associated with malarial retinopathy (MR) such as retinal whitening, vessel discoloration, and hemorrhages, are highly specific to CM, and their detection can improve the accuracy of CM diagnosis. This paper will focus on development of an automated method for the detection of retinal whitening which is a unique sign of MR that manifests due to retinal ischemia resulting from CM. We propose to detect the whitening region in retinal color images based on multiple color and textural features. First, we preprocess the image using color and textural features of the CMYK and CIE-XYZ color spaces to minimize camera reflex. Next, we utilize color features of the HSL, CMYK, and CIE-XYZ channels, along with the structural features of difference of Gaussians. A watershed segmentation algorithm is used to assign each image region a probability of being inside the whitening, based on extracted features. The algorithm was applied to a dataset of 54 images (40 with whitening and 14 controls) that resulted in an image-based (binary) classification with an AUC of 0.80. This provides 88% sensitivity at a specificity of 65%. For a clinical application that requires a high specificity setting, the algorithm can be tuned to a specificity of 89% at a sensitivity of 82%. This is the first published method for retinal whitening detection and combining it with the detection methods for vessel discoloration and hemorrhages can further improve the detection accuracy for malarial retinopathy.

  9. Complications related to a cosmetic eye-whitening procedure.

    PubMed

    Vo, Rosalind C; Stafeeva, Ksenia; Aldave, Anthony J; Stulting, R Doyle; Moore, Quianta; Pflugfelder, Stephen C; Chungfat, Neil C; Holsclaw, Douglas S; Margolis, Todd P; Deng, Sophie X

    2014-11-01

    To report sight-threatening complications following extensive bulbar conjunctival resection and postoperative mitomycin C therapy for cosmetic eye-whitening in the United States. Retrospective noncomparative case series. Multicenter report of 9 patients referred for evaluation and management of complications following bilateral cosmetic eye whitening. Seventeen eyes of 9 patients underwent cosmetic eye-whitening performed between 2 and 48 months prior to referral to one of the centers. Sixteen of the 17 eyes had persistent conjunctival epithelial defects, with 10 eyes requiring amniotic membrane grafting to facilitate re-epithelialization. Four eyes of 2 patients developed limbal stem cell compromise confirmed with in vivo confocal laser scanning microscopy. One patient developed infectious scleritis and diplopia resulting from Tenon capsule scarring. Another patient developed scleral necrosis, secondary infectious scleritis, and infectious endophthalmitis. This patient subsequently developed noninfectious scleritis that required 3-drug-regimen immunosuppression. Severe adverse effects can occur after extensive cosmetic conjunctival resection followed by topical mitomycin C application. Patients and physicians should be aware of the potential sight-threatening complications associated with this eye-whitening procedure. Published by Elsevier Inc.

  10. Whitening non vital teeth – a case report

    PubMed Central

    Moraru, Iren; Ţuculină, Mihaela; Bătăiosu, Marilena; Gheorghiţă, Lelia; Diaconu, Oana

    2012-01-01

    Commonly used in cosmetic dentistry teeth whitening can be used combined with other restorative techniques during dental treatment. Non-vital teeth whitening is necessary whenever we need an improvement of their aspect, as it’s a known fact that these teeth can have a grey or pink-grey coloration when they are not correctly endodontical treated. PMID:24778849

  11. DOMAIN MISMATCH COMPENSATION FOR SPEAKER RECOGNITION USING A LIBRARY OF WHITENERS

    DTIC Science & Technology

    2015-05-29

    DOMAIN MISMATCH COMPENSATION FOR SPEAKER RECOGNITION USING A LIBRARY OF WHITENERS Elliot Singer and Douglas Reynolds Massachusetts Institute of...development data is assumed to be unavailable. The method is based on a generalization of data whitening used in association with i-vector length...normalization and utilizes a library of whitening transforms trained at system development time using strictly out-of-domain data. The approach is

  12. Effect of whitening dentifrices on the surface roughness of commercial composites.

    PubMed

    Barbieri, Guilherme Machado; Mota, Eduardo Gonçalves; Rodrigues-Junior, Sinval Adalberto; Burnett, Luiz Henrique

    2011-10-01

    Our study aimed to test the null hypothesis that whitening and non-whitening dentifrices affect similarly the surface roughness of commercial microhybrid composites, independent of the brushing time. One hundred and ninety-two disc-shaped specimens of Filtek Z250 (3 M/ESPE, St. Paul, MN, USA) and Rok (SDI, Australia) were built up and randomly assigned to 24 groups, based on the dentifrices used (two whitening dentifrices: Colgate Max White-Colgate-Palmolive, São Bernardo do Campo, São Paulo, Brazil and Close Up Extra Whitening-Unilever, Brasil Higiene Pessoal e Limpeza Ltda, Ipojuca, Pernambuco, Brazil; and one non-whitening dentifrice: Colgate Total 12 Clean Mint-Colgate-Palmolive), and on the simulated brushing times (24 hours, 6, 12 and 24 months). The specimens were submitted to the toothbrushing regimens after which the surface roughness (Ra) was measured. Data was submitted to analysis of variance and Tukey test (α=0.05). The composite's surface roughness was significantly affected by the composites (p=0.0007), the dentifrices (p=0.0001), and the simulated brushing time (p=0.0001). Higher roughness was observed when the whitening dentifrices were used and when the brushing time increased. Filtek Z250 was more affected than Rok, especially after 24 months of simulated brushing. Whitening dentifrices produced higher surface roughness in the composites tested. The degree of surface compromising increased with brushing time and depends on the composite's microstructure and composition. © 2011 Wiley Periodicals, Inc.

  13. Conventional and whitening toothpastes: cytotoxicity, genotoxicity and effect on the enamel surface.

    PubMed

    Camargo, Samira Esteves Afonso; Jóias, Renata Pilli; Santana-Melo, Gabriela Fátima; Ferreira, Lara Tolentino; El Achkar, Vivian Narana Ribeiro; Rode, Sigmar de Mello

    2014-12-01

    To evaluate the cytotoxicity and genotoxicity of whitening and common toothpastes, and the surface roughness of tooth enamel submitted to brushing with both toothpastes. Samples of whitening toothpastes [Colgate Whitening (CW) and Oral-B Whitening (OBW)] and regular (non-whitening) toothpastes (Colgate and Oral-B) were extracted in culture medium. Gingival human fibroblasts (FMM-1) were placed in contact with different dilutions of culture media that had been previously exposed to such materials, and the cytotoxicity was evaluated using the MTT assay. The genotoxicity was assessed by the micronucleus formation assay in Chinese hamster fibroblasts (V79). The cell survival rate and micronuclei number were assessed before and after exposure to the toothpaste extracts. For the surface roughness evaluation, 20 bovine tooth specimens, divided into four groups according to toothpastes, were submitted to 10,000 brushing cycles. The results were analyzed using the Mann-Whitney U and two-way ANOVA tests (P < 0.05). MTT assay showed that Colgate was significantly less cytotoxic than CW, Oral-B and OBW at all dilutions (P < 0.01). CW was the most cytotoxic toothpaste (P < 0.01). The whitening toothpastes showed the highest numbers of micronuclei compared to the untreated control (UC) (P < 0.01). Colgate and Oral-B toothpastes were not genotoxic compared to UC (P = 0.326). The OBW toothpaste was statistically significantly abrasive to the enamel surface (P < 0.01). The whitening toothpastes and Oral-B were cytotoxic to the cells. The whitening toothpastes were more genotoxic to cells in vitro than the common toothpastes, and genotoxicity was more pronounced in the OBW toothpaste.

  14. Incidence of tooth sensitivity after home whitening treatment.

    PubMed

    Jorgensen, Michael G; Carroll, William B

    2002-08-01

    A potential side effect of dentist-dispensed home tooth-whitening systems is tooth sensitivity. The authors conducted a randomized prospective double-blind study to determine the incidence of tooth sensitivity after home whitening treatment. Fifty adult subjects used a gel containing 15 percent carbamide peroxide and 0.11 percent fluoride ion; an additional 50 adult subjects used a placebo gel daily for four weeks. Each subject's plaque index score, gingival recession status, caries status, current dentifrice and smoking history were recorded at baseline. The researchers evaluated sensitivity weekly by interview for four weeks. Fifty-four percent of subjects in both test and control groups reported mild sensitivity; 10 percent of test subjects and 2 percent of control subjects reported moderate sensitivity; 4 percent of test subjects and no control subjects reported severe sensitivity. Sensitivity decreased with time; by the second week, no severe sensitivity was reported, and by the fourth week, no moderate sensitivity was reported. The authors found a statistically significant positive correlation between reported sensitivity and gingival recession. They found no statistically significant correlations between sensitivity and any of the other recorded parameters. Mild tooth sensitivity can be expected in approximately one-half of patients who undergo home whitening treatment using the gel studied. Approximately 10 percent of patients may experience moderate sensitivity, and 4 percent of patients may experience severe sensitivity for one to two weeks. Patients with gingival recession appear more likely to experience tooth sensitivity during home whitening treatment. Patients considering home whitening treatment should be advised that mild tooth sensitivity is a common side effect and that severe tooth sensitivity occasionally occurs. If gingival recession is present, the probability of tooth sensitivity increases, and tooth sensitivity tends to decrease as

  15. Tooth Whitening And Temperature Rise With Two Bleaching Activation Methods

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abu-ElMagd, D. M.; El-Sayad, I. I.; Abd El-Gawad, L. M.

    2009-09-27

    To measure the tooth whitening and the surface and Intrapulpal temperature increase in vitro on freshly extracted upper human central incisors after chemical, Zoom AP light and diode laser activated bleaching. Thirty caries-free upper human incisors were selected. Teeth were divided into three equal groups according to the methods of activation of the bleaching agent (n = 10). A whitening gel containing hydrogen peroxide was applied to the buccal surface of all teeth. Group I was bleached using chemically activated hydrogen peroxide gel, for three applications of 15 min each. Group II was bleached with high intensity advanced power Zoommore » activation light (Zoom AP), for three applications of 15 min each. Group III was bleached with diode laser activation technique, where the teeth were irradiated with 2 Watt diode laser for three applications of 30 sec each. The whitening degree was assessed using an image analysis system, while temperature rise was recorded using a thermocouple on the external tooth surface and Intrapulpal. The degree of whitening increased significantly in all groups. However, the percentage of whitening was not statistically significantly different between the three groups. In addition, group II showed statistically significant higher mean rise in both surface and pulp temperatures than group I and group III. Chemical bleaching produces the same whitening effect as Zoom AP light and laser, with no surface or pulpal temperature rise. Laser application is faster and produces less surface and pulp temperature increase than Zoom AP light. Diode laser used to activate bleaching gels is not considered dangerous to the vitality of dental pulp using power settings of 2 W.« less

  16. Double-blind whitening Night-Guard study using ten percent carbamide peroxide.

    PubMed

    Ouellet, D; Los, S; Case, H; Healy, R

    1992-01-01

    The conservative technique of professionally dispensed and supervised, home-administered vital bleaching is now a routine treatment in the dental profession. This double-blind study evaluated the Rembrandt Lightening Gel and Whitening Toothpaste for shade change, colorimeter shade change. As well, it evaluated soft tissue health by periodontal probing, plaque index, and bleeding index. A patient questionnaire evaluated perception of whitening, perception of oral hygiene, average hours per day, and average days per week. Bleaching trays were worn over a 4-week period. The bleaching system showed definitive whitening effects as evaluated with the Vita shade guide and the colorimeter. The bleaching system had no deleterious effects on the soft tissue. The Rembrandt toothpaste alone demonstrated two-shade lightening. This vital bleaching system shows definitive whitening of the teeth in short periods of time with no adverse effects.

  17. Electromyogram whitening for improved classification accuracy in upper limb prosthesis control.

    PubMed

    Liu, Lukai; Liu, Pu; Clancy, Edward A; Scheme, Erik; Englehart

    2013-09-01

    Time and frequency domain features of the surface electromyogram (EMG) signal acquired from multiple channels have frequently been investigated for use in controlling upper-limb prostheses. A common control method is EMG-based motion classification. We propose the use of EMG signal whitening as a preprocessing step in EMG-based motion classification. Whitening decorrelates the EMG signal and has been shown to be advantageous in other EMG applications including EMG amplitude estimation and EMG-force processing. In a study of ten intact subjects and five amputees with up to 11 motion classes and ten electrode channels, we found that the coefficient of variation of time domain features (mean absolute value, average signal length and normalized zero crossing rate) was significantly reduced due to whitening. When using these features along with autoregressive power spectrum coefficients, whitening added approximately five percentage points to classification accuracy when small window lengths were considered.

  18. [Retinal whitening following vitrectomy for epiretinal macular membrane].

    PubMed

    Uemura, A

    1993-09-01

    To investigate the clinical pictures of retinal whitening following epiretinal membrane dissection. I studied retrospectively the records of 18 eyes which had undergone vitrectomy. Two types of retinal whitening were observed: cotton wool-like spots within the superficial retinal layers and a linear or dendritic pattern within the deep retinal layers. The spots were mainly noted in idiopathic cases and resolved completely in a few weeks, and the pattern was observed in macular pucker cases after retinal detachment surgery and persisted for a long time after vitrectomy.

  19. Impact of gaps in the asteroseismic characterization of pulsating stars. I. The efficiency of pre-whitening

    NASA Astrophysics Data System (ADS)

    Pascual-Granado, J.; Suárez, J. C.; Garrido, R.; Moya, A.; Hernández, A. García; Rodón, J. R.; Lares-Martiz, M.

    2018-06-01

    Context. It is known that the observed distribution of frequencies in CoRoT and Kepler δ Scuti stars has no parallelism with any theoretical model. Pre-whitening is a widespread technique in the analysis of time series with gaps from pulsating stars located in the classical instability strip, such as δ Scuti stars. However, some studies have pointed out that this technique might introduce biases in the results of the frequency analysis. Aims: This work aims at studying the biases that can result from pre-whitening in asteroseismology. The results will depend on the intrinsic range and distribution of frequencies of the stars. The periodic nature of the gaps in CoRoT observations, only in the range of the pulsational frequency content of the δ Scuti stars, is shown to be crucial to determining their oscillation frequencies, the first step in performing asteroseismology of these objects. Hence, here we focus on the impact of pre-whitening on the asteroseismic characterization of δ Scuti stars. Methods: We select a sample of 15 δ Scuti stars observed by the CoRoT satellite, for which ultra-high-quality photometric data have been obtained by its seismic channel. In order to study the impact on the asteroseismic characterization of δ Scuti stars we perform the pre-whitening procedure on three datasets: gapped data, linearly interpolated data, and data with gaps interpolated using Autoregressive and Moving Average models (ARMA). Results: The different results obtained show that at least in some cases pre-whitening is not an efficient procedure for the deconvolution of the spectral window. Therefore, in order to reduce the effect of the spectral window to a minimum, in addition to performing a pre-whitening of the data, it is necessary to interpolate with an algorithm that is aimed to preserve the original frequency content. Tables 5-49 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http

  20. KHG26792 Inhibits Melanin Synthesis in Mel-Ab Cells and a Skin Equivalent Model

    PubMed Central

    Li, Hailan; Kim, Jandi; Hahn, Hoh-Gyu; Yun, Jun; Jeong, Hyo-Soon; Yun, Hye-Young; Baek, Kwang Jin; Kwon, Nyoun Soo; Min, Young Sil; Park, Kyoung-Chan

    2014-01-01

    The purpose of this study is to characterize the effects of KHG26792 (3-(naphthalen-2-yl(propoxy) methyl)azetidine hydrochloride), a potential skin whitening agent, on melanin synthesis and identify the underlying mechanism of action. Our data showed that KHG26792 significantly reduced melanin synthesis in a dose-dependent manner. Additionally, KHG26792 downregulated microphthalmia-associated transcription factor (MITF) and tyrosinase, the rate-limiting enzyme in melanogenesis, although tyrosinase was not inhibited directly. KHG26792 activated extracellular signal-regulated kinase (ERK), whereas an ERK pathway inhibitor, PD98059, rescued KHG26792-induced hypopigmentation. These results suggest that KHG26792 decreases melanin production via ERK activation. Moreover, the hypopigmentary effects of KHG26792 were confirmed in a pigmented skin equivalent model using Cervi cornus Colla (deer antler glue), in which the color of the pigmented artificial skin became lighter after treatment with KHG26792. In summary, our findings suggest that KHG26792 is a novel skin whitening agent. PMID:24976765

  1. KHG26792 Inhibits Melanin Synthesis in Mel-Ab Cells and a Skin Equivalent Model.

    PubMed

    Li, Hailan; Kim, Jandi; Hahn, Hoh-Gyu; Yun, Jun; Jeong, Hyo-Soon; Yun, Hye-Young; Baek, Kwang Jin; Kwon, Nyoun Soo; Min, Young Sil; Park, Kyoung-Chan; Kim, Dong-Seok

    2014-06-01

    The purpose of this study is to characterize the effects of KHG26792 (3-(naphthalen-2-yl(propoxy) methyl)azetidine hydrochloride), a potential skin whitening agent, on melanin synthesis and identify the underlying mechanism of action. Our data showed that KHG26792 significantly reduced melanin synthesis in a dose-dependent manner. Additionally, KHG26792 downregulated microphthalmia-associated transcription factor (MITF) and tyrosinase, the rate-limiting enzyme in melanogenesis, although tyrosinase was not inhibited directly. KHG26792 activated extracellular signal-regulated kinase (ERK), whereas an ERK pathway inhibitor, PD98059, rescued KHG26792-induced hypopigmentation. These results suggest that KHG26792 decreases melanin production via ERK activation. Moreover, the hypopigmentary effects of KHG26792 were confirmed in a pigmented skin equivalent model using Cervi cornus Colla (deer antler glue), in which the color of the pigmented artificial skin became lighter after treatment with KHG26792. In summary, our findings suggest that KHG26792 is a novel skin whitening agent.

  2. Influence of whitening and regular dentifrices on orthodontic clear ligature color stability.

    PubMed

    Oliveira, Adauê S; Kaizer, Marina R; Salgado, Vinícius E; Soldati, Dener C; Silva, Roberta C; Moraes, Rafael R

    2015-01-01

    This study evaluated the effect of brushing orthodontic clear ligatures with a whitening dentifrice containing a blue pigment (Close Up White Now, Unilever, London, UK) on their color stability, when exposed to a staining agent. Ligatures from 3M Unitek (Monrovia, CA, USA) and Morelli (Sorocaba, SP, Brazil) were tested. Baseline color measurements were performed and nonstained groups (control) were stored in distilled water whereas test groups were exposed for 1 hour daily to red wine. Specimens were brushed daily using regular or whitening dentifrice. Color measurements were repeated after 7, 14, 21, and 28 days using a spectrophotometer based on the CIE L*a*b* system. Decreased luminosity (CIE L*), increased red discoloration (CIE a* axis), and increased yellow discoloration (CIE b* axis) were generally observed for ligatures exposed to the staining agent. Color variation was generally lower in specimens brushed with regular dentifrice, but ligatures brushed with whitening dentifrice were generally less red and less yellow than regular dentifrice. The whitening dentifrice led to blue discoloration trend, with visually detectable differences particularly apparent according to storage condition and ligature brand. The whitening dentifrice containing blue pigment did not improve the ligature color stability, but it decreased yellow discoloration and increased a blue coloration. The use of a whitening dentifrice containing blue pigment during orthodontic treatment might decrease the yellow discoloration of elastic ligatures. © 2015 Wiley Periodicals, Inc.

  3. Effect of laser irradiation on crystalline structure of enamel surface during whitening treatment with hydrogen peroxide.

    PubMed

    Son, Jung-Hyun; An, Ji-Hae; Kim, Byung-Kuk; Hwang, In-Nam; Park, Yeong-Joon; Song, Ho-Jun

    2012-11-01

    This study is to evaluate the effect of laser activation on the whitening and crystalline structure of enamel surface during whitening treatment with hydrogen peroxide. Bovine teeth were treated with whitening gel containing 35% hydrogen peroxide. A whitening gel was applied on the enamel surface for a period of 5 min, and then irradiated using a diode laser (740 nm) during whitening treatment for 0, 30, 60, 120 and 180s for the GL0-W, GL30-W, GL60-W, GL120-W and GL180-W groups, respectively. The total whitening application time was 30 min for all groups. Laser-irradiated enamel groups showed a similar lightness compared to the GL0-W group. The thickness of porous layer observed on the enamel surface of GL0-W group was decreased by increasing the laser irradiation time. While the Ca and P contents of the GL0-W group were lower than those of the non-whitening treated group (GL0-C), the Ca and P contents of the GL180-W group were similar to those of the GL180-C group. The enamel crystallinity was dramatically decreased by whitening treatment without laser irradiation. However, the decrease of crystallinity was protected by laser irradiation during whitening treatment. Raman measurement verified that laser irradiation could prevent the loss of mineral compositions on enamel and maintain its crystalline structure. The professional whitening treatment with hydrogen peroxide and diode laser activation improves not only the whitening effect but also protects the change of enamel structure compared to the treatment with only gel. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Studies on preparation of medium fat liquid dairy whitener from buffalo milk employing ultrafiltration process.

    PubMed

    Khatkar, Sunil Kumar; Gupta, Vijay Kumar; Khatkar, Anju Boora

    2014-09-01

    A study was conducted to develop good quality medium fat liquid dairy whitener from buffalo milk employing ultrafiltration (UF) process. The buffalo skim milk was UF concentrated to 4.05 to 4.18 (23.63 ± 0.30 % TS) fold and standardized to 10 % fat (on Dry Matter Basis) (i.e. formulation) and homogenized at 175.76 kg/cm(2). The addition of 0.4 % mixture of monosodium and disodium phosphate (2:1 w/w) improved the heat stability of homogenized formulation to an optimum of 66 min. The bland flavour of homogenized formulation with added 0.4 % mixture of monosodium phosphate and disodium phosphate (2:1 w/w) and 18 % sugar (on DMB) (i.e. medium fat liquid dairy whitener) was improved significantly (P < 0.01) with the addition of 0.2 % potassium chloride, but heat stability of medium fat liquid dairy whitener got reduced substantially (i.e. 19 min). With subsequent heat treatment to 85 °C for 5 min, heat stability of medium fat liquid dairy whitener got improved to reasonable level of 27 min. Whitening ability in terms of L* value of medium fat liquid dairy whitener in both tea and coffee was significantly (P < 0.01) better when homogenized at 175.76 kg/cm(2) vis-à-vis 140.61 kg/cm(2). Standardized medium fat liquid dairy whitener had significantly (P < 0.01) greater protein content (i.e. approximately 2.43 times) compared to market dairy whitener samples. At 2 % solids level, standardized medium fat liquid dairy whitener in tea/coffee fetched significantly (P < 0.01) better sensory attributes and instrumental whitening ability compared to market sample at 3 % solids level. There could be clear 33 % solids quantity saving in case of developed product compared to market dairy whitener sample.

  5. Stain removal and whitening by baking soda dentifrice: A review of literature.

    PubMed

    Li, Yiming

    2017-11-01

    Tooth discoloration may be caused by intrinsic or extrinsic stains or a combination of both. There are 2 major approaches to removing the stains, including the chemical mechanism using peroxides for tooth bleaching and the mechanical mechanism using abrasives in prophylactic pastes and dentifrices to remove stains, resulting in a whitening effect. Attempts have also been made to add a low concentration of peroxides to dentifrices to enhance their abrasive cleaning to remove tooth stains. This article provides a review of both in vitro and clinical studies on stain removal and whitening effect of dentifrices containing sodium bicarbonate (baking soda). In recent years, whitening dentifrices have become popular because of little additional effort for use, ease of availability, low cost, and accumulated evidence of clinical efficacy and safety in the literature. Advances in research and technology have led to innovative formulations of dentifrices using baking soda as the sole abrasive or a component of an abrasive system. Baking soda is biologically compatible with acid-buffering capacities, antibacterial at high concentrations, and has a relatively lower abrasivity. The evidence available in the literature indicates that baking soda-based dentifrices are effective and safe for tooth stain removal and consequently whitening. A number of clinical studies have also shown that baking soda-based dentifrices are more effective in stain removal and whitening than some non-baking soda-containing dentifrices with a higher abrasivity. So far, research efforts have mainly focused on stain removal and tooth-whitening efficacy and clinical safety of baking soda dentifrices used with manual toothbrushes, with only a few studies investigating their effects using powered toothbrushes, for which further research is encouraged. As part of a daily oral hygiene practice, baking soda-based dentifrice is a desirable, alternative or additional measure for tooth stain removal and whitening

  6. Skin Penetration Enhancement by Natural Oils for Dihydroquercetin Delivery.

    PubMed

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

    2017-09-12

    Natural oils are commonly used in topical pharmaceutical formulations as emulsifiers, stabilizers or solubility enhancers. They are presented as safe and inert components, mainly used for formulation purposes. It is confirmed that natural oils can affect the skin penetration of various substances. Fatty acids are mainly responsible for this effect. Current understanding lacks reliable scientific data on penetration of natural oils into the skin and their skin penetration enhancement potential. In the current study, fatty acid content analysis was used to determine the principal fatty acids in soybean, olive, avocado, sea-buckthorn pulp, raspberry seed and coconut oils. Time of flight secondary ion mass spectrometry bioimaging was used to determine the distribution of these fatty acids in human skin ex vivo after application of the oils. Skin penetration enhancement ratios were determined for a perspective antioxidant compound dihydroquercetin. The results demonstrated skin penetration of fatty acids from all oils tested. Only soybean and olive oils significantly increased the skin distribution of dihydroquercetin and can be used as skin penetration enhancers. However, no correlation can be determined between the fatty acids' composition and skin penetration enhancement using currently available methodological approaches. This indicates that potential chemical penetration enhancement should be evaluated during formulation of topically applied products containing natural oils.

  7. Amyloidosis presented with whitening and loss of hair which improved after dimethylsulfoxide (DMSO) treatment.

    PubMed

    Hsieh, S D; Yamamoto, R; Saito, K; Iwamoto, Y; Kuzuya, T; Ohba, S; Kobori, S; Saito, K

    1987-08-01

    A 67-year-old male patient presented with rapid progression of whitening and loss of hair in past 2 months was consulted due to the suspicion of hypothyroidism. He had been told to have cardiomegaly for 3 years. Thyroid function was within normal limit. Prostate biopsy was performed because of prostatic hypertrophy and mild elevation of serum acid phosphatase. Amyloid accumulation was observed in the biopsy specimen. Subsequent skin biopsies revealed the same result. The scalp hair and beard grew and turned to black gradually several months after dimethyl sulfoxide (DMSO) treatment. These findings suggest that some of the manifestation of amyloidosis may respond to DMSO treatment.

  8. Whitening of endodontically untreated calcified anterior teeth.

    PubMed

    Pedorella, C A; Meyer, R D; Woollard, G W

    2000-01-01

    Definitive treatment for whitening endodontically untreated anterior teeth with dystrophic calcification is provided by removing the coronal sclerotic dentin and utilizing internal and external bleaching as necessary.

  9. Effect of pH on whitening efficacy of 35% hydrogen peroxide and enamel microhardness.

    PubMed

    Jurema, Ana Luiza Barbosa; de Souza, Mauricio Yugo; Torres, Carlos Rocha Gomes; Borges, Alessandra Bühler; Caneppele, Taciana Marco Ferraz

    2018-03-01

    This study aimed to evaluate the effect of 35% hydrogen peroxide at different pH values and the degree of tooth staining on whitening efficacy and enamel microhardness. 90 enamel-dentin specimens were obtained from bovine incisors. They were randomly divided into 2 groups (n = 45), 1 group was immersed in a staining broth for 14 days, and another group was not stained and kept in distilled water at 37°C. Twenty-four hours after the staining procedure, each group was distributed into 3 subgroups that were whitened by 35% hydrogen peroxide with different pH values (5, 7, and 8.4) for 30 minutes. The color was measured at baseline and 7 days after whitening. Microhardness was measured at baseline, immediate, 24 hours, and 1 month after the whitening procedure. Data were submitted to 2-way analysis of variance (ANOVA) and the Tukey test for multiple comparisons for color analysis. Repeated measures ANOVA and the Tukey test were used to analyze microhardness data. The color change of the stained groups (ΔE 00  = 4.6) was significantly higher than that of the nonstained groups (ΔE 00  = 3.7). Microhardness value decreased significantly immediately after whitening for all subgroups and did not return to initial values. For each measurement time, microhardness was not significantly different among subgroups with different pH values. Despite the effectiveness of 35% hydrogen peroxide, changes on gel pH did not affect the whitening efficacy, and the enamel was superficially demineralized, regardless of pH values. Independently of the pH value of whitening gel, enamel undergoes superficial demineralization and with a reduction in superficial microhardness that does not return to the initial values. However, using hydrogen peroxide with different pH values does not alter the whitening effect. © 2018 Wiley Periodicals, Inc.

  10. Mercury Levels in Locally Manufactured Mexican Skin-Lightening Creams

    PubMed Central

    Peregrino, Claudia P.; Moreno, Myriam V.; Miranda, Silvia V.; Rubio, Alma D.; Leal, Luz O.

    2011-01-01

    Mercury is considered one of the most toxic elements for plants and animals. Nevertheless, in the Middle East, Asia and Latin America, whitening creams containing mercury are being manufactured and purchased, despite their obvious health risks. Due to the mass distribution of these products, this can be considered a global public health issue. In Mexico, these products are widely available in pharmacies, beauty aid and health stores. They are used for their skin lightening effects. The aim of this work was to analyze the mercury content in some cosmetic whitening creams using the cold vapor technique coupled with atomic absorption spectrometry (CV-AAS). A total of 16 skin-lightening creams from the local market were investigated. No warning information was noted on the packaging. In 10 of the samples, no mercury was detected. The mercury content in six of the samples varied between 878 and 36,000 ppm, despite the fact that the U.S. Food and Drug Administration (FDA) has determined that the limit for mercury in creams should be less than 1 ppm. Skin creams containing mercury are still available and commonly used in Mexico and many developing countries, and their contents are poorly controlled. PMID:21776243

  11. Effect of Whitening Toothpastes on Dentin Abrasion: An In Vitro Study.

    PubMed

    Vieira, Gustavo Henrique Apolinario; Nogueira, Marcia Bessa; Gaio, Eduardo Jose; Rosing, Cassiano Kuchenbecker; Santiago, Sergio Lima; Rego, Rodrigo Otavio

    To compare the effect of toothbrushing abrasion with hydrated silica-based whitening and regular toothpastes on root dentin using contact profilometry. Ninety dentin specimens (4 x 4 x 2 mm) were randomly divided into five experimental groups (n = 18) according to the toothpaste: three whitening (W1, W2 and W3) and two regular toothpastes (R1 and R2) produced by two different manufacturers. Using a brushing machine, each specimen was brushed with a constant load of 300 g for 2500 cycles (4.5 cycles/s). The toothpastes were diluted at a ratio of 1:3 w/w (dentifrice:distilled water). The brush diamond tip of the profilometer moved at a constant speed of 0.05 mm/s with a force of 0.7 mN. The average value of brushing abrasion in μm (mean ± SD) was obtained from five consecutive measurements of each specimen: W1 = 8.86 ± 1.58, W2 = 7.59 ± 1.04, W3 = 8.27 ± 2.39, R1 = 2.89 ± 1.05 and R2= 2.94 ± 1.29. There was a significant difference between groups (ANOVA, p<0.0001). Post-hoc Tukey's test for multiple comparisons showed differences between all the whitening and regular toothpastes, but not among the whitening nor among the regular toothpastes. The whitening toothpastes tested can cause more dentin abrasion than the regular ones.

  12. The influence of a novel in-office tooth whitening procedure using an Er,Cr:YSGG laser on enamel surface morphology.

    PubMed

    Dionysopoulos, Dimitrios; Strakas, Dimitrios; Koliniotou-Koumpia, Eugenia

    2015-08-01

    The purpose of this in vitro study was to evaluate the influence of a novel in-office tooth whitening procedure using Er,Cr:YSGG laser radiation on bovine enamel. Forty-eight enamel specimens were prepared from bovine canines and divided into four groups: Group 1 specimens (control) received no whitening treatment; Group 2 received whitening treatment with an at-home whitening agent (22% carbamide peroxide) for 7 days; Group 3 received whitening treatment with a novel in-office whitening agent (35% H(2)O(2)); Group 4 received the same in-office whitening therapy with Group 3 using Er,Cr:YSGG laser in order to accelerate the whitening procedure. The specimens were stored for 10 days after the whitening treatment in artificial saliva. Vickers hardness was determined using a microhardness tester and surface roughness was evaluated using a VSI microscope. Three specimens of each experimental group were examined under SEM and the mineral composition of the specimens was evaluated using EDS. Data were statistically analyzed using one-way ANOVA, Tukey's post-hoc test, Wilcoxon signed rank and Kruskal-Wallis tests (a = 0.05). The surface microhardness of the enamel was reduced after the in-office whitening treatments (P< 0.05), but not influenced after the at-home whitening treatment (P> 0.05). Moreover, the surface roughness was not significantly changed after tooth whitening. EDS analysis did not show alterations in the enamel mineral composition, while SEM observations indicated changes in the surface morphology, especially after in-office tooth whitening (P< 0.05). The laser-assisted whitening treatment with Er,Cr:YSGG laser did not affect the alterations in enamel surface compared with the conventional in-office whitening technique. © 2015 Wiley Periodicals, Inc.

  13. Effectiveness and mode of action of whitening dentifrices on enamel extrinsic stains.

    PubMed

    Alshara, Salem; Lippert, Frank; Eckert, George J; Hara, Anderson T

    2014-01-01

    This study was conducted in order to investigate the mode of action and the whitening effect of whitening dentifrices. Two hundred fifty-six bovine enamel specimens (10 × 10 mm(2)) were prepared, partially stained, and assigned into eight groups (n = 32): six whitening dentifrices, one nonwhitening and deionized water (negative control), and further divided in two subgroups (n = 16), according to the test model: chemical (dentifrice slurry treatment only) or chemo-mechanical (slurry + toothbrushing). Specimens were treated with dentifrice slurries 2 ×/day for 1 min and toothbrushed or not, according to each model. In between dentifrice treatments, specimens were artificially stained for 5 h. This protocol was repeated for 5 days and enamel color changes (∆E) were measured after each day (days 1-5). The abrasive level of the dentifrices was determined following the ISO11609 guidelines. In the chemo-mechanical model, the whitening action of all dentifrices was observed after day 1, being higher than the negative control group (p < 0.05). In days 2-5, nonsignificant changes in color were observed for all groups (p > 0.05). Differences on ∆E among dentifrices were observed, and they seemed to correlate well with their abrasive level (r(2) = 0.80). In the chemical model, no significant differences were observed among groups (p > 0.05), with ∆E remaining constant throughout the study. Higher ∆E values were observed in the chemo-mechanical model compared to the chemical (p < 0.05). All tested dentifrices were effective in whitening stained enamel and their mode of action showed to be mainly mechanical (toothbrushing abrasion). The abrasive level of dentifrices seems to determine its whitening effectiveness.

  14. a Test to Prove Cloud Whitening THEORY!

    NASA Astrophysics Data System (ADS)

    Buttram, J. W.

    2011-12-01

    Climate science researchers believe our planet can possibly tolerate twice the present carbon dioxide levels with no upwards temperature change, IF we could increase the amount of energy reflected back out into space by about 2.0%. (c)Cloudtec basically alters a blend of seawater and applies heat derived from magma to it at a temperature exceeding 2,000 degrees F. The interaction of seawater and magma displaces the oxygen, causing the volume of water to vaporize and expand over 4,000 times - transforming billions of tons of seawater into thousands of cubic miles of white, maritime, stratocumulus clouds to reflect the incident Sun's rays back out into space. A 6 month test to prove Cloud Whitening Theory will cost 6 million dollars. (No profit added.) This study will enable everyone on the planet with a computer the transparency to use satellite imagery and check out for themselves - if and when Cloud Whitening is occurring. If Cloud Whitening Theory is validated, (c)Cloudtec's innovation can strategically create the clouds we need to reflect the Sun's rays back out into space and help neutralize the projected 3.6 degrees F rise in temperature. Based on reasonable calculations of anthropogenic global warming: this one move alone would be comparable to slashing global carbon dioxide emissions by over 60% over the next 40 years.

  15. Dielectrophoresis enhances the whitening effect of carbamide peroxide on enamel.

    PubMed

    Ivanoff, Chris S; Hottel, Timothy L; Garcia-Godoy, Franklin; Riga, Alan T

    2011-10-01

    To compare the enamel whitening effect of a 20-minute dielectrophoresis enhanced electrochemical delivery to a 20-minute diffusion treatment. Forty freshly extracted human teeth without detectable caries or restoration were stored in distilled water at 4 degrees C and used within 1 month of extraction. Two different bleaching gels (Plus White 5 Minute Speed Whitening Gel and 35% Opalescence PF gel) were tested. The study had two parts: Part 1--Quantitative comparison of hydrogen peroxide (H2O2, HP) absorption--following application of an over-the-counter 35% HP whitening gel (Plus White 5 Minute Speed Whitening Gel) to 30 (n = 30) extracted human teeth by conventional diffusion or dielectrophoresis. The amount of H2O2 that diffused from the dentin was measured by a colorimetric oxidation-reduction reaction kit. HP concentration was measured by UV-Vis spectroscopy at 550 nm. Part 2--HP diffusion in stained teeth--35% carbamide peroxide whitening gel (35% Opalescence PF gel) was applied to 10 extracted human teeth (n = 10) stained by immersion in a black tea solution for 48 hours. The teeth were randomly assigned to the 20-minute dielectrophoresis or diffusion treatment group; whitening was evaluated by a dental spectrophotometer and macro-photography. Part 1: The analysis found significant differences between both groups with relative percent errors of 3% or less (a single outlier had an RPE of 12%). The average absorbance for the dielectrophoresis group in round 1 was 79% greater than the diffusion group. The average absorbance for the dielectrophoresis group in round 2 was 130% greater than the diffusion group. A single-factor ANOVA found a statistically significant difference between the diffusion and dielectrophoresis groups (P = 0.01). Part 2--The average change in Shade Guide Units (SGU) was 0.6 for the diffusion group, well under the error of measurement of 0.82 SGU. The average change in SGU for the dielectrophoresis group was 9, significantly above the

  16. Physical-chemical characteristics of whitening toothpaste and evaluation of its effects on enamel roughness.

    PubMed

    Hilgenberg, Sérgio Paulo; Pinto, Shelon Cristina Souza; Farago, Paulo Vitor; Santos, Fábio André; Wambier, Denise Stadler

    2011-01-01

    This in vitro study evaluated the physical-chemical characteristics of whitening toothpastes and their effect on bovine enamel after application of a bleaching agent (16% carbamide peroxide). Physical-chemical analysis was made considering mass loss by desiccation, ash content and pH of the toothpastes. Thirty bovine dental enamel fragments were prepared for roughness measurements. The samples were subjected to bleaching treatments and simulated brushing: G1. Sorriso Dentes Brancos (Conventional toothpaste), G2. Close-UP Whitening (Whitening toothpaste), and G3. Sensodyne Branqueador (Whitening toothpaste). The average roughness (Ra) was evaluated prior to the bleaching treatment and after brushing. The results revealed differences in the physical-chemical characteristics of the toothpastes (p < 0.0001). The final Ra had higher values (p < 0.05) following the procedures. The mean of the Ra did not show significant differences, considering toothpaste groups and bleaching treatment. Interaction (toothpaste and bleaching treatment) showed significant difference (p < 0.0001). The whitening toothpastes showed differences in their physical-chemical properties. All toothpastes promoted changes to the enamel surface, probably by the use of a bleaching agent.

  17. Effect of a whitening agent application on enamel bond strength of self-etching primer systems.

    PubMed

    Miyazaki, Masashi; Sato, Hikaru; Sato, Tomomi; Moore, B Keith; Platt, Jeffrey A

    2004-06-01

    Though reduction in bond strength after tooth whitening has been reported, little is known about it's effect on enamel bond strength of two-step bonding systems that exclude phosphoric acid etching prior to bonding agent application. The purpose of this study was to determine the effect of whitening procedure using an in-office whitening agent on enamel bond strength of self-etching primer systems. Three self-etching primer systems, Imperva Fluoro Bond, Mac Bond II, Clearfil SE Bond, and a one-bottle adhesive system Single Bond as a control material, were used. Bovine mandibular incisors were mounted in self-curing resin and the facial enamel or dentin surfaces were ground wet on 600-grit SiC paper. An in-office whitening agent, Hi-Lite was applied on the tooth surface according to the manufacturer's instruction. Bonding procedures were done soon after rinsing off the whitening agent or after 24 hours storage in distilled water. Specimens without whitening procedure were prepared as controls. Fifteen specimens per test group were stored in 37 degrees C distilled water for 24 hours, then shear tested at a crosshead speed of 1.0 mm/minute. One-way ANOVA followed by Duncan multiple range test were used for statistical analysis of the results. For the specimens made soon after rinsing off the whitening agent, a significant decrease in enamel bond strength was observed for all the bonding systems used. For the specimens made after 24 hours storage in water, a small decrease in enamel bond strength was observed and no significant differences were found compared to those of controls (without whitening). From the results of this study, enamel bond strengths of the self-etching primer systems might be affected to a lesser degree after rinsing with water followed by 24 hours storage in water.

  18. On estimating attenuation from the amplitude of the spectrally whitened ambient seismic field

    NASA Astrophysics Data System (ADS)

    Weemstra, Cornelis; Westra, Willem; Snieder, Roel; Boschi, Lapo

    2014-06-01

    Measuring attenuation on the basis of interferometric, receiver-receiver surface waves is a non-trivial task: the amplitude, more than the phase, of ensemble-averaged cross-correlations is strongly affected by non-uniformities in the ambient wavefield. In addition, ambient noise data are typically pre-processed in ways that affect the amplitude itself. Some authors have recently attempted to measure attenuation in receiver-receiver cross-correlations obtained after the usual pre-processing of seismic ambient-noise records, including, most notably, spectral whitening. Spectral whitening replaces the cross-spectrum with a unit amplitude spectrum. It is generally assumed that cross-terms have cancelled each other prior to spectral whitening. Cross-terms are peaks in the cross-correlation due to simultaneously acting noise sources, that is, spurious traveltime delays due to constructive interference of signal coming from different sources. Cancellation of these cross-terms is a requirement for the successful retrieval of interferometric receiver-receiver signal and results from ensemble averaging. In practice, ensemble averaging is replaced by integrating over sufficiently long time or averaging over several cross-correlation windows. Contrary to the general assumption, we show in this study that cross-terms are not required to cancel each other prior to spectral whitening, but may also cancel each other after the whitening procedure. Specifically, we derive an analytic approximation for the amplitude difference associated with the reversed order of cancellation and normalization. Our approximation shows that an amplitude decrease results from the reversed order. This decrease is predominantly non-linear at small receiver-receiver distances: at distances smaller than approximately two wavelengths, whitening prior to ensemble averaging causes a significantly stronger decay of the cross-spectrum.

  19. Effect of various tooth whitening modalities on microhardness, surface roughness and surface morphology of the enamel.

    PubMed

    Kwon, So Ran; Kurti, Steven R; Oyoyo, Udochukwu; Li, Yiming

    2015-09-01

    The purpose of this study was to evaluate the effect of four whitening modalities on surface enamel as assessed with microhardness tester, profilometer, and scanning electron microscopy (SEM). Whitening was performed according to manufacturer's directions for over-the-counter (OTC), dentist dispensed for home use (HW) and in-office (OW) whitening. Do-it-yourself (DIY) whitening consisted of a strawberry and baking soda mix. Additionally, negative and positive controls were used. A total of 120 enamel specimens were used for microhardness testing at baseline and post-whitening. Following microhardness testing specimens were prepared for SEM observations. A total of 120 enamel specimens were used for surface roughness testing at baseline and post-whitening (n = 20 per group). Rank-based Analysis of Covariance was performed to compare microhardness and surface roughness changes. Tests of hypotheses were two-sided with α = 0.05. There was a significant difference in Knoop hardness changes (ΔKHN) among the groups (Kruskal-Wallis test, p < 0.0001). Significant hardness reduction was observed in the positive control and DIY group (p < 0.0001). Mean surface roughness changes (ΔRa) were significantly different among the groups (Kruskal-Wallis test, p < 0.0001). Surface roughness increased in the OTC group (p = 0.03) and in the positive control (p < 0.0001). The four whitening modalities-DIY, OTC, HW and OW induced minimal surface morphology changes when observed with SEM. It can be concluded that none of the four whitening modalities adversely affected enamel surface morphology. However, caution should be advised when using a DIY regimen as it may affect enamel microhardness and an OTC product as it has the potential to increase surface roughness.

  20. Vascular rarefaction mediates whitening of brown fat in obesity

    PubMed Central

    Shimizu, Ippei; Aprahamian, Tamar; Kikuchi, Ryosuke; Shimizu, Ayako; Papanicolaou, Kyriakos N.; MacLauchlan, Susan; Maruyama, Sonomi; Walsh, Kenneth

    2014-01-01

    Brown adipose tissue (BAT) is a highly vascularized organ with abundant mitochondria that produce heat through uncoupled respiration. Obesity is associated with a reduction of BAT function; however, it is unknown how obesity promotes dysfunctional BAT. Here, using a murine model of diet-induced obesity, we determined that obesity causes capillary rarefaction and functional hypoxia in BAT, leading to a BAT “whitening” phenotype that is characterized by mitochondrial dysfunction, lipid droplet accumulation, and decreased expression of Vegfa. Targeted deletion of Vegfa in adipose tissue of nonobese mice resulted in BAT whitening, supporting a role for decreased vascularity in obesity-associated BAT. Conversely, introduction of VEGF-A specifically into BAT of obese mice restored vascularity, ameliorated brown adipocyte dysfunction, and improved insulin sensitivity. The capillary rarefaction in BAT that was brought about by obesity or Vegfa ablation diminished β-adrenergic signaling, increased mitochondrial ROS production, and promoted mitophagy. These data indicate that overnutrition leads to the development of a hypoxic state in BAT, causing it to whiten through mitochondrial dysfunction and loss. Furthermore, these results link obesity-associated BAT whitening to impaired systemic glucose metabolism. PMID:24713652

  1. Effectiveness of a new dentifrice with baking soda and peroxide in removing extrinsic stain and whitening teeth.

    PubMed

    Ghassemi, A; Hooper, W; Vorwerk, L; Domke, T; DeSciscio, P; Nathoo, S

    2012-01-01

    The primary purpose of this randomized, controlled, six-week clinical trial was to determine the effectiveness and safety of a new whitening dentifrice in removing extrinsic tooth stain and whitening teeth. An additional two-week exploratory study was conducted to determine whether the whitening or stain-prevention activity of the dentifrice would persist following cessation of use. In the first study (Phase I), one-hundred and forty-six qualifying subjects were randomly assigned to either a sodium bicarbonate whitening dentifrice group (Arm & Hammer Advance White Extreme Whitening Baking Soda and Peroxide Toothpaste) or a silica-based negative control dentifrice group, and brushed twice daily with their assigned dentifrice for six weeks. Tooth shade on the labial surfaces of the eight incisors was assessed using a Vita Classic shade guide, and extrinsic tooth stain was scored using a Modified Lobene Stain Index (MLSI) at baseline, week 4, and week 6. In Phase II (after the week 6 examination), volunteers from the Arm & Hammer whitening dentifrice group were randomly assigned to continue using the whitening dentifrice or to use the negative control dentifrice twice daily for two weeks. The six-week shade and stain index scores served as the baseline for this exploratory phase and were rescored after two weeks. The whitening dentifrice group had statistically significant (p < 0.0001) mean shade score reductions of 1.82 and 2.57 from baseline to weeks 4 and 6, respectively. For the same periods, the negative control dentifrice group was virtually unchanged from baseline. For tooth stain, the MLSI total mean scores for the whitening dentifrice group showed statistically significant (p < 0.0001) decreases from baseline of 1.42 (41.6%) and 2.11 (61.6%) at weeks 4 and 6, respectively. In contrast, the negative control dentifrice group had a MLSI reduction of 0.07 at week 4 and a 0.06 increase at week 6. Between-group analyses using baseline-adjusted ANCOVA showed the

  2. Micro-structural integrity of dental enamel subjected to two tooth whitening regimes.

    PubMed

    Tanaka, Reina; Shibata, Yo; Manabe, Atsufumi; Miyazaki, Takashi

    2010-04-01

    Colour modification of tooth enamel has proven successful, but it is unclear how various bleaching applications affect micro-structural integrity of the whitened enamel. To investigate the internal structural integrity of human intact tooth enamel with the application of two commonly used whitening regimes (in-office power bleaching with 35% hydrogen peroxide and home bleaching with 10% carbamide peroxide), evaluations were performed on teeth of identical colour classification. After the bleaching applications, the enamel mineral density was quantified and visualised with micro-computed tomography. The micro-structural differences between the whitened tooth enamel samples were distinctive, though the colour parameter changes within the samples were equivalent. Home bleaching achieved colour modification by demineralisation, whereas in-office bleaching depended on redistribution of the minerals after treatment and subsequent enhanced mineralisation.

  3. Efficacy of tooth whitening with different calcium phosphate-based formulations.

    PubMed

    Jin, Jian; Xu, Xiaohui; Lai, Guangyun; Kunzelmann, Karl-Heinz

    2013-08-01

    The aim of this in-vitro study was to evaluate the efficacy of tooth whitening using different calcium phosphate-based formulations. Teeth were treated with three different hydroxyapatite preparations at different concentrations and with two control preparations; each tooth was treated a total of three times. After application of the last material, hydrodynamic shear force was applied to mimic mechanical loading. After each treatment, tooth color was measured using a dental spectrophotometer, and the mean changes in L*a*b* values between different measurements were expressed as ∆E. The results indicated significant differences between the materials, but neither dose- nor time-dependent associations were found. The suspension containing tricalcium phosphate (10 wt%) showed the most obvious color change (∆E = 2.20 ± 0.90), while the suspension containing zinc-carbonate-apatite (20 wt%) showed the least obvious color change (∆E = 0.91 ± 0.50). Calcium phosphate-based formulations that can adhere to the enamel surface and contribute to tooth whitening have promising tooth-whitening potential. © 2013 Eur J Oral Sci.

  4. Tooth whitening evaluation of blue covarine containing toothpastes.

    PubMed

    Tao, Danying; Smith, Richard N; Zhang, Qiong; Sun, Jianing N; Philpotts, Carole J; Ricketts, Stephen R; Naeeni, Mojgan; Joiner, Andrew

    2017-12-01

    To measure the tooth whitening effects delivered immediately after brushing with silica-based toothpastes containing blue covarine in vitro and in vivo. Salivary pellicle coated human extracted teeth were brushed with either a slurry of a toothpaste containing blue covarine (BC), a formulation containing an increased level of blue covarine (BC+) or a negative control toothpaste containing no blue covarine. The colour of the specimens were measured in vitro using either a Minolta chromameter or a VITA Easyshade spectrophotometer, before and after brushing and changes in CIELAB values and tooth Whiteness Index (WIO) values calculated. In a double-blind cross-over clinical study, subjects brushed with either BC or BC+ toothpaste and tooth colour changes were measured with a digital image analysis system. The in vitro studies demonstrated that toothpastes containing blue covarine gave a significantly (p<0.05) greater change in b* and WIO values than the negative control toothpaste; the BC+ toothpaste gave a significantly greater increase in b* and WIO values than the BC toothpaste, and BC+ gave a significant increase in shade change versus the negative control. Clinical results showed that BC and BC+ gave a significant reduction in b* (p<0.0001) and increase in WIO (p<0.0001) from baseline indicating significant tooth whitening had occurred. The parameter changes were significantly greater when brushing with the BC+ toothpaste than with the BC toothpaste (WIO p=0.006; b* p=0.013). Toothpastes containing blue covarine gave a statistically significant reduction in tooth yellowness and improvement in tooth whiteness immediately after brushing in both in vitro and clinical studies. In addition, the higher concentration blue covarine toothpaste gave statistically significant greater tooth whitening benefits than the lower concentration blue covarine toothpaste. The silica-based toothpastes containing blue covarine evaluated in the current study gave tooth whitening benefits

  5. Premature hair whitening is an independent predictor of carotid intima-media thickness in young and middle-aged men.

    PubMed

    Erdoğan, Turan; Kocaman, Sinan Altan; Çetin, Mustafa; Durakoğlugil, Murtaza Emre; Uğurlu, Yavuz; Şahin, İsmail; Çanga, Aytun

    2013-01-01

    Premature graying or whitening of the hair may possibly represent premature atherosclerotic changes as a surrogate marker of different host responses to cardiovascular risk factors (CVRFs). This study was undertaken to test whether carotid artery intima-media thickness (CIMT) as a validated surrogate marker of the severity and extent of coronary artery disease (CAD) is higher in subjects with prominent signs of hair whitening, independent of chronological age and other CVRFs. The current study was conducted in young and middle-aged patients (<55 years age) without a history of cardiovascular disease. Two hundred and two eligible patients consecutively admitted to our outpatient clinic for CVRF management were included. A gray/white-hair scale was used to determine the percentage of hair whitening. In the groups determined according to the degree of hair whitening, age (p<0.001), waist circumference (p=0.011), the presence of hypertension (p=0.003), the uric acid levels (p=0.008), the C - reactive protein levels (p=0.002) and CIMT (p<0.001) were significantly different. When we performed multivariate analyses to determine the independent predictors of CIMT and hair whitening, CIMT was found to be related to age, waist circumference, the levels of uric acid, bilirubin and gamma-glutamyl transpeptidase, the presence of a family history of CAD and hair whitening, while hair whitening was found to be related to age, hypertension, the bilirubin level and CIMT. Our findings suggest that premature hair whitening intensity is independently related to CIMT. In cumulative assessments of CVRFs on the human body, the presence of premature hair whitening may be useful in identifying individuals with an increased risk of cardiovascular disease.

  6. Immunofluorescence findings in rapid whitening of scalp hair.

    PubMed

    Guin, J D; Kumar, V; Petersen, B H

    1981-09-01

    Rapid whitening of scalp hair developed during a three-month period along with a diffuse, subtotal alopecia in a patient. Immunofluorescence microscopy of biopsy material showed prominent deposits of IgG and IgM in a granular pattern in the epithelium of the lower portions of hair follicles. Some return of the color and amount of scalp hair occurred within a year, but occasional bouts of hair loss continued to occur. It is theorized that the rapid graying was caused by a selective loss of pigmented hair, which was perhaps caused by an immunologic mechanism. Some of the findings suggest that the cause of this patient's loss of hair color may be different from those of patients who have been previously described as having rapid whitening of scalp hair because of alopecia areata or vitiligo.

  7. New Whitening Constituents from Taiwan-Native Pyracantha koidzumii: Structures and Tyrosinase Inhibitory Analysis in Human Epidermal Melanocytes.

    PubMed

    Lin, Rong-Dih; Chen, Mei-Chuan; Liu, Yan-Ling; Lin, Yi-Tzu; Lu, Mei-Kuang; Hsu, Feng-Lin; Lee, Mei-Hsien

    2015-12-02

    Nontoxic natural products useful in skin care cosmetics are of considerable interest. Tyrosinase is a rate-limiting enzyme for which its inhibitor is useful in developing whitening cosmetics. Pyracantha koidzumii (Hayata) Rehder is an endemic species in Taiwan that exhibits tyrosinase-inhibitory activity. To find new active natural compounds from P. koidzumii, we performed bioguided isolation and studied the related activity in human epidermal melanocytes. In total, 13 compounds were identified from P. koidzumii in the present study, including two new compounds, 3,6-dihydroxy-2,4-dimethoxy-dibenzofuran (9) and 3,4-dihydroxy-5-methoxybiphenyl-2'-O-β-d-glucopyranoside (13), as well as 11 known compounds. The new compound 13 exhibited maximum potency in inhibiting cellular tyrosinase activity, the protein expression of cellular tyrosinase and tyrosinase-related protein-2, as well as the mRNA expression of Paired box 3 and microphthalmia-associated transcription factor in a concentration-dependent manner. In the enzyme kinetic assay, the new compound 13 acted as an uncompetitive mixed-type inhibitor against the substrate l-3,4-dihydroxyphenylalanine and had a Km value against this substrate of 0.262 mM, as calculated using the Lineweaver-Burk plots. Taken together, our findings show compound 13 exhibits tyrosinase inhibition in human melanocytes and compound 13 may be a potential candidate for use in cosmetics.

  8. New Whitening Constituents from Taiwan-Native Pyracantha koidzumii: Structures and Tyrosinase Inhibitory Analysis in Human Epidermal Melanocytes

    PubMed Central

    Lin, Rong-Dih; Chen, Mei-Chuan; Liu, Yan-Ling; Lin, Yi-Tzu; Lu, Mei-Kuang; Hsu, Feng-Lin; Lee, Mei-Hsien

    2015-01-01

    Nontoxic natural products useful in skin care cosmetics are of considerable interest. Tyrosinase is a rate-limiting enzyme for which its inhibitor is useful in developing whitening cosmetics. Pyracantha koidzumii (Hayata) Rehder is an endemic species in Taiwan that exhibits tyrosinase-inhibitory activity. To find new active natural compounds from P. koidzumii, we performed bioguided isolation and studied the related activity in human epidermal melanocytes. In total, 13 compounds were identified from P. koidzumii in the present study, including two new compounds, 3,6-dihydroxy-2,4-dimethoxy-dibenzofuran (9) and 3,4-dihydroxy-5-methoxybiphenyl-2ʹ-O-β-d-glucopyranoside (13), as well as 11 known compounds. The new compound 13 exhibited maximum potency in inhibiting cellular tyrosinase activity, the protein expression of cellular tyrosinase and tyrosinase-related protein-2, as well as the mRNA expression of Paired box 3 and microphthalmia-associated transcription factor in a concentration-dependent manner. In the enzyme kinetic assay, the new compound 13 acted as an uncompetitive mixed-type inhibitor against the substrate l-3,4-dihydroxyphenylalanine and had a Km value against this substrate of 0.262 mM, as calculated using the Lineweaver–Burk plots. Taken together, our findings show compound 13 exhibits tyrosinase inhibition in human melanocytes and compound 13 may be a potential candidate for use in cosmetics. PMID:26633381

  9. Can Whitening Strips interfere with the Bond Strength of Composite Resins?

    PubMed

    Firoozmand, Leily Macedo; Reis, Washington Luís Machado dos; Vieira, Mercêdes Aroucha; Nunes, Adriana Gomes; Tavarez, Rudys Rodolfo de Jesus; Tonetto, Mateus Rodrigues; Bramante, Fausto Silva; Bhandi, Shilpa H; Roma, Regina Vieira de Oliveira; Bandeca, Matheus Coelho

    2015-04-01

    The aim of this study was to investigate in vitro the bond strength of composite resins on enamel previously treated with whitening strips. A total of 48 bovine incisors were allocated to four experimental groups (n = 12 each): G1 (WSC)- treated with 9.5% hydrogen peroxide whitening strips (3D White Whitestrips® Advanced Vivid/CREST); G2 (WSO)-treated with 10% hydrogen peroxide whitening strips (3D WhiteTM/Oral B); G3 (WG)-treated with 7.5% hydrogen peroxide gel with fluorine, calcium and potassium nitrate (White Class®/FGM); and G4 (C)-control not subjected to bleaching treatment. The specimens were subjected to bleaching over 2 weeks following the manufacturers' instructions. Following the elaboration of the composite resin test specimens, the samples were stored in artificial saliva and subsequently subjected to the micro-shear test using the universal testing machine (EMIC®). The bond strength values were analyzed by one-way ANOVA and Tukey's statistical test (5%). Significant differences were observed among the investigated groups (p < 0.05). The G3-WG exhibited greater values compared with the control group and the groups treated with strips, G1-WSC and G2-WSO. Analysis of the bond interface revealed that a large fraction of the failures occurred at the enamel-resin interface. The bond strength decreased following 14 days of treatment with bleaching strips, whereas the whitening gel with 7.5% hydrogen peroxide, calcium and fluorine increased the bond strength.

  10. Effects of regular and whitening dentifrices on remineralization of bovine enamel in vitro.

    PubMed

    Kielbassa, Andrej M; Tschoppe, Peter; Hellwig, Elmar; Wrbas, Karl-Thomas

    2009-02-01

    To compare in vitro the remineralizing effects of different regular dentifrices and whitening dentifrices (containing pyrophosphates) on predemineralized enamel. Specimens from 84 bovine incisors were embedded in epoxy resin, partly covered with nail varnish, and demineralized in a lactic acid solution (37 degrees C, pH 5.0, 8 days). Parts of the demineralized areas were covered with nail varnish, and specimens were randomly assigned to 6 groups. Subsequently, specimens were exposed to a remineralizing solution (37 degrees C, pH 7.0, 60 days) and brushed 3 times a day (1:3 slurry with remineralizing solution) with 1 of 3 regular dentifrices designed for anticaries (group 1, amine; group 2, sodium fluoride) or periodontal (group 3, amine/stannous fluoride) purposes or whitening dentifrice containing pyrophosphates (group 4, sodium fluoride). An experimental dentifrice (group 5, without pyrophosphates/fluorides) and a whitening dentifrice (group 6, monofluorophosphate) served as controls. Mineral loss and lesion depths were evaluated from contact microradiographs, and intergroup comparisons were performed using the closed-test procedure (alpha =.05). Compared to baseline, specimens brushed with the dentifrices containing stannous/amine fluorides revealed significant mineral gains and lesion depth reductions (P < .05). Concerning the reacquired mineral, the whitening dentifrice performed worse than the regular dentifrices (P > .05), while mineral gain, as well as lesion depth, reduction was negligible with the control groups. Dentifrices containing pyrophosphates perform worse than regular dentifrices but do not necessarily affect remineralization. Unless remineralizing efficacy is proven, whitening dentifrices should be recommended only after deliberate consideration in caries-prone patients.

  11. Citric acid compounds of tangerines peel extract (Citrus reticulata) as potential materials teeth whitening

    NASA Astrophysics Data System (ADS)

    Pratiwi, F.; Tinata, J. K.; Prakasa, A. W.; Istiqomah; Hartini, E.; Isworo, S.

    2017-04-01

    Peel of citrus fruit (Citrus reticulata) has a variety of possible chemical compounds that may serve as a potential whitening teeth. This research is conducted on a laboratory scale; therefore, it needs to be developed on an application scale. A quasi-experimental was employed in this study. Citric acid extraction was carried out on the type of Sweet Orange (Citrus Aurantium L), Tangerine (Citrus Reticulata Blanco or Citrus Nobilis), Pomelo (Citrus Maxima Merr, Citrus grandis Osbeck), and Lemon (Citrus Limon Linn). Citric acid’s ability test as teeth whitener was performed on premolar teeth with concentrations of 2.5%, 5%, and 10%. The experiments were replicated in 3 times, and teeth whiteness level was measured using Shade Guide VITA Classical. The result of this research showed that citric acid in every kind of orange peel with various concentration has different abilities on whitening teeth. The highest colour level obtained from Tangerine peel’s citric acid concentration of 5%. Orange peel extract has the best teeth whitening abilities tested by the method of Gass Chromatography to know the active ingredients.

  12. Effects of toothbrushing with fluoride abrasive and whitening dentifrices on both unbleached and bleached human enamel surface in terms of roughness and hardness: an in vitro study.

    PubMed

    Bolay, Sukran; Cakir, Filiz Yalcin; Gurgan, Sevil

    2012-09-01

    The aim of this in vitro study was to evaluate the surface roughness and hardness of both unbleached and bleached (opalescence; 10% carbamide peroxide) human enamel brushed with water (without dentifrice), fluoride abrasive dentifrice (Colgate Total) and whitening dentifrice (Natural White). Human enamel samples were obtained from third molars and randomly divided into five groups (n = 8): G1 - Control (brushed with water without dentifrice), G2 - Colgate Total (fluoride abrasive dentifrice), G3 - Natural White (whitening dentifrice), G4 - Opalescence (10% carbamide peroxide) and then brushed with Colgate Total, G5 - Opalescence (10% carbamide peroxide) and then brushed with Natural White. Bleaching regimen was applied according to manufacturers' instructions. The brushing process was performed with a modified Nyffenegger's brushing machine. Surface roughness was analyzed with a profilometer. Microhardness testing was performed with a Brinell hardness tester. Results were statistically analyzed by Kruskal-Wallis, one-way ANOVA analysis and Mann-Whitney U, Wilcoxon matched-pairs signed-ranks tests. There were significant differences in surface roughness values for all groups, which showed an increase in roughness (p < 0.05). When the bleaching treatment combined with brushing with whitening dentifrice was performed (G5), there was a significant decrease in hardness values (p < 0.05). The other groups (G1, G2, G3, G4) showed no significant hardness differences (p > 0.05). It was concluded that toothbrushing procedures increased the enamel surface roughness, and that bleaching regimen performed with cleaning treatment, through brushing with whitening dentifrice decreased hardness values. When applied together, bleaching and cleaning treatments may alter the enamel surface roughness and hardness values.

  13. Schinus terebinthifolius Raddi extract and linoleic acid from Passiflora edulis synergistically decrease melanin synthesis in B16 cells and reconstituted epidermis.

    PubMed

    Jorge, A T S; Arroteia, K F; Santos, I A; Andres, E; Medina, S P H; Ferrari, C R; Lourenço, C B; Biaggio, R M T T; Moreira, P L

    2012-10-01

    Several treatments for skin whitening are available today, but few of them are completely adequate, especially owing to the carcinogenic potential attributed to classical drugs like hydroquinone, arbutin and kojic acid. To provide an alternative and safer technology for whitening, we developed two botanical compounds originated from Brazilian biodiversity, an extract of Schinus terebinthifolius Raddi and a linoleic acid fraction isolated from Passiflora edulis oil. The whitening effect of these compounds was assessed using biochemical assays and in vitro models including cellular assays and equivalent skin. The results showed that S. terebinthifolius Raddi extract is able to reduce the tyrosinase activity in vitro, and the combination of this extract with linoleic acid is able to decrease the level of melanin produced by B16 cells cultured with melanocyte-stimulating hormone. Furthermore, melanin was also reduced in human reconstituted epidermis (containing melanocytes) treated with the compounds. The combination of the compounds may provide a synergistic positive whitening effect rather than their isolated use. Finally, we demonstrated that the performance of these mixed compounds is comparable to classical molecules used for skin whitening, as kojic acid. This new natural mixture could be considered an alternative therapeutic agent for treating hyperpigmentation and an effective component in whitening cosmetics. © 2012 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  14. In vitro cariostatic effect of whitening toothpastes in human dental enamel-microhardness evaluation.

    PubMed

    Watanabe, Melina Mayumi; Rodrigues, José Augusto; Marchi, Giselle Maria; Ambrosano, Gláucia Maria Bovi

    2005-06-01

    The aim of this study was to evaluate, in vitro, the cariostatic effect of whitening toothpastes. Ninety-five dental fragments were obtained from nonerupted third molars. The fragments were embedded in polystyrene resin and sequentially polished with abrasive papers (400-, 600-, and 1,000-grit) and diamond pastes of 6, 3, and 1 microm. The fragments were assigned in five groups according to toothpaste treatment: G1 = Rembrandt Plus with Peroxide; G2 = Crest Dual Action Whitening; G3 = Aquafresh Whitening Triple Protection; and the control groups: G4 = Sensodyne Original (without fluoride); G5 = Sensodyne Sodium Bicarbonated (with fluoride). The initial enamel microhardness evaluations were done. For 2 weeks the fragments were submitted daily to a de-remineralization cycle followed by a 10-minute toothpaste slurry. After that, the final microhardness tests were done. The percentage of mineral loss of enamel was determined for statistical analysis. Analysis of variance and the Tukey test were applied. The results did not show statistically significant differences in mineral loss among groups G1, G2, G3, and G5, which statistically differ from G4 (toothpaste without fluoride). G4 showed the highest mineral loss (P < or = .05). The whitening toothpastes evaluated showed a cariostatic effect similar to regular, nonwhitening toothpaste.

  15. Effect of Light-Activated Tooth Whitening on Color Change Relative to Color of Artificially Stained Teeth.

    PubMed

    Kwon, So Ran; Kurti, Steven R; Oyoyo, Udochukwu; Li, Yiming

    2015-01-01

    There is still controversy as to the efficacy of light activation used in tooth whitening. The purpose of this study was to evaluate the effect of light activation on tooth color change relative to the artificial dye color. Extracted human third molars (160) were randomly distributed into eight groups of 20 specimens each based on artificial staining and use of light activation. All groups received three 45-minute sessions of in-office whitening at 3-day intervals. Color measurements were performed with an intraoral spectrophotometer at baseline prior to staining (T0), after artificial staining (T1), 1-day--(T2), and 1-week--(T3) post-whitening. Color differences were calculated relative to after artificial staining color parameters (L*1, a*1, b*1) with the use of a software analysis program enabling synchronization of two images. Within the same staining groups, the light-activated samples exhibited a greater color change than their nonlight-activated counterparts. However, only in the case of the yellow-stained samples at 1-day post-whitening was there a significant difference between the nonlight-activated and light-activated groups (Tukey's post hoc multiple comparison test for pairwise comparisons, p < 0.05). Light activation is a valid method for enhancing the efficacy of tooth whitening with respect to overall color change and works best with yellow stains. Light activation is a valid method for enhancing the efficacy of tooth whitening with respect to overall color change and works best with yellow stains.

  16. Effects of different preparation procedures during tooth whitening on enamel bonding.

    PubMed

    Wilson, Dustin; Xu, Changqi; Hong, Liang; Wang, Yong

    2009-04-01

    The objective of this study was to assess effects of some clinically related preparation procedures during tooth whitening on enamel bonding properties. Sixty-two extracted human teeth were cleaned and divided into four groups. Forty-two of the teeth were left with their natural surface intact while 20 teeth were polished to form a flat surface. Half of the tooth served as the experimental side and received one of the two whitening products: Opalescence (10% carbamide peroxide) and Crest Whitestrips (6.5% hydrogen peroxide), for 2 weeks. Post-bleaching intervals included: 1 day, 1 week, and 2 weeks. On these days, tooth (10 mm x 1.5 mm x 1.5 mm) sections were evaluated using Raman spectroscopy, scanning electron microscopy and tensile bond strength tests. T-test, ANOVA test, and mixed model regression analysis were used to assess the differences. No significant difference existed between natural surface and polished surface teeth for all groups at both Day One and Week Two (P > 0.05). On Day One, both treated groups had significant lower bond strength than the control group (P = 0.002). After 2 weeks, no significant difference existed between any group (P = 0.381). SEM indicated that resin-enamel interfaces in bleached enamel exhibited more defects in granular formations when compared to the control. Raman results indicated a lower degree of polymerization (DP) of adhesive at the interface for treated teeth surfaces. In summary, pre-bleaching surface treatments such as polish or non-polish, had no effect on bond strength. Bleaching significantly decreased bond strength initially, but after 2 weeks, bleaching had no significant effect on bond strength. Storage time had significant effect on Opalescence treated enamel, but not on control and Whitestrip treated enamel. The decrease of bond strength may be related to interfacial defects and low DP due to oxygen release after bleaching.

  17. Encapsulation of natural ingredient for skin protection via nanoemulsion process

    NASA Astrophysics Data System (ADS)

    Asmatulu, Eylem; Usta, Aybala; Alzahrani, Naif; Patil, Vinay; Vanderwall, Adeesha

    2017-04-01

    Many of the sunscreens are used during the hot summer time to protect the skin surface. However, some of ingredients in the sunscreens, such as oxybenzone, retinyl palmitate and synthetic fragrances including parabens, phthalates and synthetic musk may disrupt the cells on the skin and create harmful effects to human body. Natural oils may be considered for substitution of harmful ingredients in sunscreens. Many natural oils (e.g., macadamia oil, sesame oil, almond oil and olive oil) have UV protective property and on top of that they have natural essences. Among the natural oils, olive oil has a long history of being used as a home remedy for skincare. Olive oil is used or substituted for cleanser, moisturizer, antibacterial agent and massage reliever for muscle fatigue. It is known that sun protection factor (SPF) of olive oil is around eight. There has been relatively little scientific work performed on the effect of olive oil on the skin as sunscreen. With nanoencapsulation technique, UV light protection of the olive oil can be extended which will provide better coverage for the skin throughout the day. In the present study, natural olive oil was incorporated with DI water and surfactant (sodium dodecyl sulfate - SDS) and sonicated using probe sonicators. Sonication time, and concentrations of olive oil, DI water and surfactant were investigated in detail. The produced nanoemulsions were characterized using dynamic light scattering, and UV-Vis spectroscopy. It is believed that the nanoencupsulation of olive oil could provide better skin protection by slow releasing and deeper penetration of the nanoemulsion on skin surface. Undergraduate engineering students were involved in the project and observed all the process during the laboratory studies, as well as data collection, analysis and presentation. This experience based learning will likely enhance the students' skills and interest in the scientific and engineering studies.

  18. Effect of four over-the-counter tooth-whitening products on enamel microhardness.

    PubMed

    Majeed, A; Grobler, S R; Moola, M H; Oberholzer, T G

    2011-10-01

    This in vitro study evaluated the effect of four over-the-counter tooth-whitening products on enamel microhardness. Fifty enamel blocks were prepared from extracted human molar teeth. The enamel surfaces were polished up to 1200 grit fineness and the specimens randomly divided into five groups. Enamel blocks were exposed to: Rapid White (n=10); Absolute White (n=10); Speed White (n=10) and White Glo (n=10) whitening products, according to the manufacturers' instructions. As control, ten enamel blocks were kept in artificial saliva at 37 degrees C without any treatment. Microhardness values were obtained before exposure (baseline) and after 1, 7 and 14-day treatment periods using a digital hardness tester with a Vickers diamond indenter. Data were analysed using Wilcoxon Signed Rank Sum Test, one-way ANOVA and Tukey-Kramer Multiple Comparison Test (p<0.05). Both Rapid White and Absolute White reduced enamel microhardness. Speed White increased the microhardness of enamel, while White Glo and artificial saliva had no effect on hardness. Over-the-counter tooth-whitening products might decrease enamel microhardness depending on the type of product.

  19. A Simple Recipe for Whitening Old Newspaper Clippings.

    ERIC Educational Resources Information Center

    Carter, Henry A.

    1995-01-01

    Describes a method for experimenting with both whitening and deacidifying old newspaper clippings using sodium borohydride bleaching. Clippings are soaked in distilled water then immersed in sodium borohydride for 15-20 minutes. After rinsing with distilled water, the paper is washed with saturated Ca(OH)2 solution. Readers should not begin…

  20. Can whitening toothpastes maintain the optical stability of enamel over time?

    PubMed

    Silva, Eduardo Moreira da; Maia, Juliana Nunes da Silva Meirelles Dória; Mitraud, Carine Gnatiuk; Russo, Juliana do Espírito Santo; Poskus, Laiza Tatiana; Guimarães, José Guilherme Antunes

    2018-02-01

    Besides the effects on the health of individuals, cigarette smoking can also interfere with the appearance of their teeth. To evaluate the effect of cigarette smoking-toothbrushing-cycling (CSTC) with whitening toothpastes on the roughness and optical behavior of bovine enamel for eight weeks. Thirty bovine dentin/enamel discs, 8.0 mm in diameter and 2.0 mm thick, were randomly divided into three groups according to the toothpastes: whitening (Colgate Luminous White - CW and Oral B 3D White - OW), and a non-whitening (Colgate - C). The roughness, color (CIE L*a*b* system), translucency and gloss were measured before and after the specimens were submitted to CSTC. The topography of the specimens was analyzed by scanning electron microscopy. During the first week, the specimens were daily subjected to the consumption of 20 cigarettes and brushed (40 strokes/100 g) with the toothpastes' slurries. Thereafter, the CSTC was weekly applied in an accumulated model (140 cigarettes/280 strokes) for seven weeks. The data were submitted to two-way ANOVA, Tukey's HSD test, and paired-t test (α=0.05). The three toothpastes produced significant changes in roughness, color, translucency and gloss (p<0.05). After eight weeks, the roughness and the gloss produced by the three toothpastes were similar (p>0.05), while OW produced the lowest color change and the translucency of C was lower than that of CW (p<0.05). The three toothpastes produced a significant decrease in L* values and a significant increase in a* values after eight weeks (p<0.05). No significant difference in the b* coordinate was found for OW (p=0.13) There were topographic changes in the enamel surfaces. The whitening toothpastes increased the roughness, changed the topography and were not able to maintain the optical stability of enamel exposed over eight weeks.

  1. Whitening the single discolored tooth.

    PubMed

    Kwon, So Ran

    2011-04-01

    This article discusses the possible methods available for whitening of a single discolored tooth. Treatment options can vary from restorative procedures such as crowns, veneers, or bonding to more conservative bleaching treatments. The long-term success of the treatment is dictated by proper diagnosis and treatment planning. The cause and severity of the discoloration has to be carefully evaluated when planning for bleaching options. The vitality of the pulp, presence and absence of symptoms, and periapical pathoses usually determine whether an external or internal bleaching approach will be considered. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. The effect of three whitening oral rinses on enamel micro-hardness.

    PubMed

    Potgieter, E; Osman, Y; Grobler, S R

    2014-05-01

    The purpose of this study was to determine the effect on human enamel micro-hardness of three over-the-counter whitening oral rinses available in South Africa. Enamel fragments were gathered into three groups of 15 each. One group was exposed to Colgate Plax Whitening Blancheur, the second group to White Glo 2 in 1 and the third to Plus White, in each case for periods recommended by the respective manufacturers. Surface micro-hardness of all groups was measured before and after a 14 day treatment period. pH levels of the oral rinses were also determined with a combination pH electrode. Pre- and post- treatment data were analysed by the Wilcoxon Signed Rank Sum Test. According to the micro-hardness values no significant (p > 0.05) enamel damage was found as a result of treatment. However, it was observed that Colgate Pax and White Glo decreased the enamel hardness, an early sign of enamel damage, while Plus White showed a small increase in hardness. The three whitening oral rinses on the South African market do not damage the tooth enamel significantly when used as recommended by the manufacturers. However, extending the contact period and increasing the frequency of application might lead to damage of enamel.

  3. Investigation of water-soluble elastin as a multifunctional cosmetic material: Moisturizing and whitening effects.

    PubMed

    Inoue, Asako; Hikima, Tomohiro; Taniguchi, Suguru; Nose, Takeru; Maeda, Iori

    Elastin and collagen are extracellular matrix proteins that are widely distributed in the body. Although elastin essentially functions as a skin moisturizer, there have been few reports on its other fundamental chemical and biological functions. In this study, we investigated the moisturizing and whitening (tyrosinase inhibition) effects of elastin to examine its usefulness as a cosmetic material. Water-soluble hot alkali pig aorta (HAPA)-elastin was prepared from pig aorta using the hot alkali method. HAPA-elastin showed a widely distributed molecular weight and had a coacervation property that mediated reversible self-assembly of its molecules with increasing temperature. Amino acid analysis of HAPA-elastin showed a high content (81.5%) of hydrophobic amino acids such as Gly, Ala, Val, and Pro. Des (desmosine) and Ide (isodesmosine), which are characteristic amino acids of elastin, accounted for more than 0.4% of the total amino acid content. HAPA-elastin showed a moisture-retaining property. The water content of skin samples treated with and without HAPA-elastin was 77.2% ± 7.8% and 49.4% ± 10.1%, respectively. HAPA-elastin also inhibited tyrosinase activity by 11.3% ± 3.9%. The results obtained indicate that elastin has a useful function as a cosmetic material.

  4. Application of a zero-latency whitening filter to compact binary coalescence gravitational-wave searches

    NASA Astrophysics Data System (ADS)

    Tsukada, Leo; Cannon, Kipp; Hanna, Chad; Keppel, Drew; Meacher, Duncan; Messick, Cody

    2018-05-01

    Joint electromagnetic and gravitational-wave (GW) observation is a major goal of both the GW astronomy and electromagnetic astronomy communities for the coming decade. One way to accomplish this goal is to direct follow-up of GW candidates. Prompt electromagnetic emission may fade quickly, therefore it is desirable to have GW detection happen as quickly as possible. A leading source of latency in GW detection is the whitening of the data. We examine the performance of a zero-latency whitening filter in a detection pipeline for compact binary coalescence (CBC) GW signals. We find that the filter reproduces signal-to-noise ratio (SNR) sufficiently consistent with the results of the original high-latency and phase-preserving filter for both noise and artificial GW signals (called "injections"). Additionally, we demonstrate that these two whitening filters show excellent agreement in χ2 value, a discriminator for GW signals.

  5. Skin bioprinting: a novel approach for creating artificial skin from synthetic and natural building blocks.

    PubMed

    Augustine, Robin

    2018-05-12

    Significant progress has been made over the past few decades in the development of in vitro-engineered substitutes that mimic human skin, either as grafts for the replacement of lost skin, or for the establishment of in vitro human skin models. Tissue engineering has been developing as a novel strategy by employing the recent advances in various fields such as polymer engineering, bioengineering, stem cell research and nanomedicine. Recently, an advancement of 3D printing technology referred as bioprinting was exploited to make cell loaded scaffolds to produce constructs which are more matching with the native tissue. Bioprinting facilitates the simultaneous and highly specific deposition of multiple types of skin cells and biomaterials, a process that is lacking in conventional skin tissue-engineering approaches. Bioprinted skin substitutes or equivalents containing dermal and epidermal components offer a promising approach in skin bioengineering. Various materials including synthetic and natural biopolymers and cells with or without signalling molecules like growth factors are being utilized to produce functional skin constructs. This technology emerging as a novel strategy to overcome the current bottle-necks in skin tissue engineering such as poor vascularization, absence of hair follicles and sweat glands in the construct.

  6. Toothpastes containing abrasive and chemical whitening agents: efficacy in reducing extrinsic dental staining.

    PubMed

    Soares, Cristina Neves Girao Salgado; Amaral, Flavia Lucisano Botelho do; Mesquita, Marcelo Ferraz; Franca, Fabiana Mantovani Gomes; Basting, Roberta Tarkany; Turssi, Cecilia Pedroso

    2015-01-01

    This in vitro study evaluated the efficacy of toothpastes containing abrasive and chemical whitening agents in reducing the extrinsic discoloration of dental enamel. Sixty slabs of dentin from human teeth were sealed so that only the enamel surface was exposed. The enamel surfaces were photographed for initial color assessment. Staining was performed by immersing the dental slabs in 0.2% chlorhexidine solution for 2 minutes and then in black tea for 60 minutes. This process was repeated 15 times. Photographs were taken at the end of the staining process, and the slabs were divided into 5 groups (n = 12), 3 to be brushed with toothpastes containing chemical whitening agents (2 containing phosphate salts and 1 containing phosphate salts plus hydrogen peroxide) and 2 to represent control groups (ordinary/nonwhitening toothpaste and distilled water). The dental slabs were subjected to mechanical toothbrushing with toothpaste slurry or distilled water, according to each group's specifications. After brushing, more photographs were taken for color analysis. The results showed a significant reduction in luminosity after the staining process in addition to an increase in the colors red and yellow (P < 0.001). After brushing, there was a significant increase in luminosity and a reduction in both red and yellow (P < 0.001). However, there was no observed difference between the changes in color values in dental enamel slabs brushed with whitening toothpastes and the changes found in slabs brushed with ordinary toothpaste. The whitening toothpastes did not outperform an ordinary toothpaste in the removal of extrinsic staining.

  7. Effect of Bleaching Gel Viscosity on Tooth Whitening Efficacy and Pulp Chamber Penetration: An In Vitro Study.

    PubMed

    Kwon, S R; Pallavi, Fnu; Shi, Y; Oyoyo, U; Mohraz, A; Li, Y

    Whitening efficacy has been related to hydrogen peroxide (HP) diffusion into tooth structure. However, little information is available relating rheological properties to whitening efficacy. The purpose was to evaluate the whitening efficacy and HP penetration level of a 10% HP gel at three different viscosities and to compare them to a strip delivery system. Extracted molars (n=120) were randomly assigned into five groups (n=24/ group): NC_MED (negative control; median): medium viscosity gel without HP; LOW: 10% HP gel (low viscosity experimental gel, Ultradent Products Inc); MED: 10% HP gel (medium viscosity experimental gel, Ultradent); HIGH: 10% HP gel (high viscosity gel, Ultradent); and CWS: Crest 3D Whitestrips 1-Hour Express (Procter & Gamble). All teeth were subjected to five 60-minute whitening sessions. Instrumental color measurements were performed at baseline (T 0 ), and 1-day after each application (T 1 -T 5 ), and 1-month after whitening (T 6 ). HP penetration was estimated with leucocrystal violet and horseradish peroxidase. A Kruskal-Wallis test and post hoc Bonferroni test were performed to assess the difference in tooth color change and HP penetration among the groups (α=0.05). Hydrogen peroxide penetration levels and overall color changes at T 6 were 0.24 μg/mL / 2.80; 0.48 μg/mL / 8.48; 0.44 μg/mL / 7.72; 0.35 μg/mL / 8.49; 0.36 μg/mL / 7.30 for groups NC, LOW, MED, HIGH, and CWS, respectively. There was a significant difference for HP penetration, while there was no significant difference among the four experimental groups for tooth color change. Rheological properties should be considered when developing new whitening formulations.

  8. Natural Antioxidants: Multiple Mechanisms to Protect Skin From Solar Radiation

    PubMed Central

    Dunaway, Spencer; Odin, Rachel; Zhou, Linli; Ji, Liyuan; Zhang, Yuhang; Kadekaro, Ana L.

    2018-01-01

    Human skin exposed to solar ultraviolet radiation (UVR) results in a dramatic increase in the production of reactive oxygen species (ROS). The sudden increase in ROS shifts the natural balance toward a pro-oxidative state, resulting in oxidative stress. The detrimental effects of oxidative stress occur through multiple mechanisms that involve alterations to proteins and lipids, induction of inflammation, immunosuppression, DNA damage, and activation of signaling pathways that affect gene transcription, cell cycle, proliferation, and apoptosis. All of these alterations promote carcinogenesis and therefore, regulation of ROS levels is critical to the maintenance of normal skin homeostasis. Several botanical products have been found to exhibit potent antioxidant capacity and the ability to counteract UV-induced insults to the skin. These natural products exert their beneficial effects through multiple pathways, including some known to be negatively affected by solar UVR. Aging of the skin is also accelerated by UVR exposure, in particular UVA rays that penetrate deep into the epidermis and the dermis where it causes the degradation of collagen and elastin fibers via oxidative stress and activation of matrix metalloproteinases (MMPs). Because natural compounds are capable of attenuating some of the UV-induced aging effects in the skin, increased attention has been generated in the area of cosmetic sciences. The focus of this review is to cover the most prominent phytoproducts with potential to mitigate the deleterious effects of solar UVR and suitability for use in topical application. PMID:29740318

  9. Can whitening toothpastes maintain the optical stability of enamel over time?

    PubMed Central

    da Silva, Eduardo Moreira; Maia, Juliana Nunes da Silva Meirelles Dória; Mitraud, Carine Gnatiuk; Russo, Juliana do Espírito Santo; Poskus, Laiza Tatiana; Guimarães, José Guilherme Antunes

    2018-01-01

    Abstract Besides the effects on the health of individuals, cigarette smoking can also interfere with the appearance of their teeth. Objective To evaluate the effect of cigarette smoking-toothbrushing-cycling (CSTC) with whitening toothpastes on the roughness and optical behavior of bovine enamel for eight weeks. Material and Methods Thirty bovine dentin/enamel discs, 8.0 mm in diameter and 2.0 mm thick, were randomly divided into three groups according to the toothpastes: whitening (Colgate Luminous White - CW and Oral B 3D White - OW), and a non-whitening (Colgate - C). The roughness, color (CIE L*a*b* system), translucency and gloss were measured before and after the specimens were submitted to CSTC. The topography of the specimens was analyzed by scanning electron microscopy. During the first week, the specimens were daily subjected to the consumption of 20 cigarettes and brushed (40 strokes/100 g) with the toothpastes' slurries. Thereafter, the CSTC was weekly applied in an accumulated model (140 cigarettes/280 strokes) for seven weeks. The data were submitted to two-way ANOVA, Tukey's HSD test, and paired-t test (α=0.05). Results The three toothpastes produced significant changes in roughness, color, translucency and gloss (p<0.05). After eight weeks, the roughness and the gloss produced by the three toothpastes were similar (p>0.05), while OW produced the lowest color change and the translucency of C was lower than that of CW (p<0.05). The three toothpastes produced a significant decrease in L* values and a significant increase in a* values after eight weeks (p<0.05). No significant difference in the b* coordinate was found for OW (p=0.13) There were topographic changes in the enamel surfaces. Conclusions The whitening toothpastes increased the roughness, changed the topography and were not able to maintain the optical stability of enamel exposed over eight weeks. PMID:29412362

  10. Natural Oils for Skin-Barrier Repair: Ancient Compounds Now Backed by Modern Science.

    PubMed

    Vaughn, Alexandra R; Clark, Ashley K; Sivamani, Raja K; Shi, Vivian Y

    2018-02-01

    Natural plant oils are commonly used as topical therapy worldwide. They are usually easily accessible and are relatively inexpensive options for skin care. Many natural oils possess specific compounds with antimicrobial, antioxidant, anti-inflammatory, and anti-itch properties, making them attractive alternative and complementary treatments for xerotic and inflammatory dermatoses associated with skin-barrier disruption. Unique characteristics of various oils are important when considering their use for topical skin care. Differing ratios of essential fatty acids are major determinants of the barrier repair benefits of natural oils. Oils with a higher linoleic acid to oleic acid ratio have better barrier repair potential, whereas oils with higher amounts of irritating oleic acid may be detrimental to skin-barrier function. Various extraction methods for oils exist, including cold pressing to make unrefined oils, heat and chemical distillation to make essential oils, and the addition of various chemicals to simulate a specific scent to make fragranced oils. The method of oil processing and refinement is an important component of selecting oil for skin care, and cold pressing is the preferred method of oil extraction as the heat- and chemical-free process preserves beneficial lipids and limits irritating byproducts. This review summarizes evidence on utility of natural plant-based oils in dermatology, particularly in repairing the natural skin-barrier function, with the focus on natural oils, including Olea europaea (olive oil), Helianthus annus (sunflower seed oil), Cocos nucifera (coconut oil), Simmondsia chinesis (jojoba oil), Avena sativa (oat oil), and Argania spinosa (argan oil).

  11. A clinical evaluation of 10 percent vs. 15 percent carbamide peroxide tooth-whitening agents.

    PubMed

    Kihn, P W; Barnes, D M; Romberg, E; Peterson, K

    2000-10-01

    Agents with carbamide peroxide, or CP, in various concentrations are widely prescribed for at-home tooth whitening. It is not clear, however, if the more concentrated gels will whitening teeth to a greater extent, as no controlled clinical trials have been reported. The authors conducted a double-blind study of human subjects to evaluate whether a 15 percent CP tooth-whitening system was more effective than a 10 percent CP system, and to determine if tooth sensitivity increased with use of the higher concentration. The authors recruited 57 subjects with maxillary anterior teeth of shade A3 or darker (as gauged against a value-oriented shade guide). The subjects were 18 to 65 years of age and in good general and dental health. After matching the subjects by sex and age, the authors randomly assigned them to either a control group, which used a 10 percent CP whitening agent, or an experimental group, which used a 15 percent CP agent. The results indicated that there was no significant difference in shade change between the groups after one week of treatment (t = 1.455, P = .05), but there was a significant difference at the end of the treatment period (t = 2.303, P < .05), as well as two weeks after treatment concluded (t = 2.248, P < .05). There was no significant difference in sensitivity (t = 1.399, P > .05). There was a significant difference in color change between the 10 percent CP and 15 percent CP groups at the end of the study period. There was no significant difference in level of tooth sensitivity between the two groups, and the incidence was equal; there was, however, a significant difference in variability of tooth sensitivity between the two groups. If performed under the careful guidance of a dentist, at-home whitening is an effective treatment, regardless of whether 10 percent CP or 15 percent CP is used. There may be added color change and varying sensitivity with the use of 15 percent CP.

  12. The Whitening of Brown Fat and Its Implications for Weight Management in Obesity.

    PubMed

    Shimizu, Ippei; Walsh, Kenneth

    2015-06-01

    Systemic inflammation resulting from dysfunction of white adipose tissue (WAT) accelerates the pathologies of diabetes and cardiovascular diseases. In contrast to WAT, brown adipose tissue (BAT) is abundant in mitochondria that produce heat by uncoupling respiratory chain process of ATP synthesis. Besides BAT's role in thermogenesis, accumulating evidence has shown that it is involved in regulating systemic metabolism. Studies have analyzed the "browning" processes of WAT as a means to combat obesity, whereas few studies have focused on the impact and molecular mechanisms that contribute to obesity-linked BAT dysfunction--a process that is associated with the "whitening" of this tissue. Compared to WAT, a dense vascular network is required to support the high energy consumption of BAT. Recently, vascular rarefaction was shown to be a significant causal factor in the whitening of BAT in mouse models. Vascular insufficiency leads to mitochondrial dysfunction and loss in BAT and contributes to systemic insulin resistance. These data suggest that BAT "whitening," resulting from vascular dysfunction, can impact obesity and obesity-linked diseases. Conversely, agents that promote BAT function could have utility in the treatment of these conditions.

  13. Comparative clinical evaluation of two professional tooth-whitening products.

    PubMed

    Kowitz, G M; Nathoo, S A; Wong, R

    1994-01-01

    A 2-week study was conducted to compare the tooth-whitening efficacy of two 10% carbamide peroxide products: Colgate Platinum Professional Toothwhitening System and Rembrandt Lighten Bleaching Gel. Fifty subjects were divided into two groups and assigned a product to use for 2 weeks. Change in tooth color was measured by reflectance spectroscopy at the initiation of study, at 1 week, and at 2 weeks into the study. Color change was calculated using the color-difference equation established by the Commission International de L'Eclairage. Results showed that Colgate Platinum was 62% more effective at tooth whitening after 1 week and 83% more effective after 2 weeks of treatment vs Rembrandt. At the termination of the study, the mean color difference (deltaE) for Colgate Platinum was 4.29 and 2.34 for Rembrandt. Statistical analysis demonstrated that the Colgate product is significantly superior at increasing tooth whiteness, increasing tooth lightness, reducing redness, and reducing yellowness. In this study, no adverse reactions were noted on clinical examination and none were reported by panelists with normal healthy dentition.

  14. An in situ investigation into the abrasion of eroded dental hard tissues by a whitening dentifrice.

    PubMed

    Turssi, C P; Faraoni, J J; Rodrigues, A L; Serra, M C

    2004-01-01

    This crossover study aimed to investigate abrasion of previously eroded hard dental tissues by a whitening dentifrice compared to a regular dentifrice. After a 3-day lead-in period, 14 volunteers were randomly assigned to use one of the toothpastes while wearing a removable appliance, containing 3 enamel and 3 root dentine slabs on each side. On the first day salivary pellicle was allowed to form. Twice daily for the following 3 days, one side of each appliance was immersed in an acidic carbonated drink ex vivo while the other side remained unexposed. Specimens were then brushed with the allocated dentifrice. After a 3-day washout period, new sets of enamel and dentine slabs were mounted in the appliances and the participants commenced period 2 using the alternative toothpaste. Acid-treated specimens always showed more wear than untreated specimens. The whitening dentifrice did not significantly increase the wear of softened enamel compared with the regular dentifrice. Brushing with the whitening toothpaste led to significantly greater wear of sound enamel and of both eroded and sound dentine than the regular dentifrice. The results suggest that whitening dentifrices may not increase the wear of acid-softened enamel but may have a more deleterious effect on dentine than regular toothpastes.

  15. Determinants of inhalant (whitener) use among street children in a South Indian city.

    PubMed

    Praveen, Devarsetty; Maulik, Pallab K; Raghavendra, Bellara; Khan, Maseer; Guggilla, Rama K; Bhatia, Prakash

    2012-08-01

    A cross-sectional study was conducted in the year 2008 among 174 children in observation homes in Hyderabad, India, to estimate the distribution of inhalant (whitener) use among this population. Data were collected using an instrument developed for this purpose. About 61% of the children were boys and their mean age was 12.2 years (range 5-18 years). Whitener use was found in 35% of the children along with concurrent use of other substances. Peer pressure was the commonest cause reported for initiating substance use. The high prevalence is an important concern for the Indian policymakers given the large number of street children in Indian cities.

  16. A clinical evaluation comparing two H2O2 concentrations used with a light-assisted chairside tooth whitening system.

    PubMed

    Ward, Marilyn; Felix, Heather

    2012-04-01

    The purpose of this study was to assess the efficacy of two different BriteSmile hydrogen peroxide (H2O2) gels in a split-arch protocol for whitening teeth in a clinical setting when used in conjunction with a BriteSmile BS4000 lamp. Fifteen subjects were enrolled into a single-center clinical trial. The efficacy of the BriteSmile BS4000 lamp using both 15% H2O2 and 25% H2O2 gel formulations was tested. Study subjects were concurrently exposed to the whitening lamp with the 15% H2O2 gel placed on half of their anterior teeth and the 25% H2O2 gel on the other half for a total light and gel exposure of 60 minutes. The clinical data collected were shade score, gingival health, and dentinal hypersensitivity self-assessment. Changes in tooth shade were better for subjects exposed to the 25% gel and the dental whitening lamp (average 8.0 shade changes) compared to subjects exposed to the 15% gel and dental whitening lamp (average 7.6 shade changes) immediately after treatment. The same held true at the 7-day follow-up (25% gel average 7.4 shade changes versus 15% gel average 7.3 shade changes). However, these differences were not statistically significant. No reports of irritation of gingival soft tissues were documented. The relative changes in mean sensitivity scores were similar for both groups with no significant differences in mean sensitivity scores between the groups. Both concentrations of H2O2 gel and the whitening lamp combined gave study subjects an average of 8.0 (25% gel) and 7.6 (15% gel) shade changes immediately after treatment. The 7-day follow-up examination resulted in a regression of lightest to an average of 7.4 (25% gel) and 7.3 (15% gel). It was concluded that the use of the chairside whitening light and either 15% or 25% hydrogen peroxide gel is safe and effective for whitening teeth in 1 hour.

  17. A clinical evaluation of bleaching using whitening wraps and strips.

    PubMed

    Matis, Bruce A; Cochran, Michael; Wang, Ge; Franco, Miguel; Eckert, George J; Carlotti, Ronald J; Bryan, Christopher

    2005-01-01

    This study evaluated the degree of color change of teeth and the sensitivities of teeth and gums in an in vivo study. Ranir Whitening Wraps (WW2) and Crest Whitestrips Premium (WP2) were used twice a day and Ranir Whitening Wraps (WW1) were used once a day. Color evaluations occurred at baseline, after five and seven-day use of bleaching agent and 14 days post-bleaching. Color change was evaluated objectively and subjectively. Sensitivity evaluations were also accomplished. Seventy-six of the 78 subjects enrolled completed the study. All three products significantly lightened teeth. WW2 lightened more than WP2 and WW1 in L*, a*, b*, E and shade guide value. WP2 lightened more than WW1 in a*, b*, E and shade guide value. There was no difference in tooth sensitivity, but WW1 and WP2 caused less gingival sensitivity than WW2. The mean age of smokers was seven years younger than nonsmokers who qualified.

  18. Relationship between arsenic skin lesions and the age of natural menopause.

    PubMed

    Yunus, Fakir Md; Rahman, Musarrat Jabeen; Alam, Md Zahidul; Hore, Samar Kumar; Rahman, Mahfuzar

    2014-05-02

    Chronic exposure to arsenic is associated with neoplastic, cardiovascular, endocrine, neuro-developmental disorders and can have an adverse effect on women's reproductive health outcomes. This study examined the relationship between arsenic skin lesions (a hallmark sign of chronic arsenic poisoning) and age of natural menopause (final menopausal period) in populations with high levels of arsenic exposure in Bangladesh. We compared menopausal age in two groups of women--with and without arsenic skin lesions; and presence of arsenic skin lesions was used as an indicator for chronic arsenic exposure. In a cross-sectional study, a total of 210 participants were randomly identified from two ongoing studies--participants with arsenic skin lesions were identified from an ongoing clinical trial and participants with no arsenic skin lesions were identified from an ongoing cohort study. Mean age of menopause between these two groups were calculated and compared. Multivariable linear regression was used to estimate the relationship between the status of the arsenic skin lesions and age of natural menopause in women. Women with arsenic skin lesions were 1.5 years younger (p <0.001) at the time of menopause compared to those without arsenic skin lesions. After adjusting with contraceptive use, body mass index, urinary arsenic level and family history of premature menopause, the difference between the groups' age at menopause was 2.1 years earlier (p <0.001) for respondents with arsenic skin lesions. The study showed a statistically significant association between chronic exposure to arsenic and age at menopause. Heavily exposed women experienced menopause two years earlier than those with lower or no exposure.

  19. A Simple Recipe for Whitening Old Newspaper Clippings

    NASA Astrophysics Data System (ADS)

    Carter, Henry A.

    1995-07-01

    Newspaper clippings tend to brown quickly with aging as the result of chromophores that form during the degradation of one or more components of paper. Newsprint that consists of approximately 40% lignin is particularly susceptible to browning due to the relative ease of the oxidation of lignin. For readers who wish to experiment with both whitening and deacidifying old newspaper clippings, a simple recipe requiring few materials is presented.

  20. [Comparison of the color difference between teeth underwent cold light whitening and two kinds of shade guides].

    PubMed

    Xu, Y X

    2018-06-18

    To investigate which shade guide, Vitapan Classical or Vita Bleachedguide 3DMaster, is better matched with the color of teeth in judging whitening effect, by comparing the color difference between shade tabs and corresponding teeth underwent cold light tooth whitening. A total of 60 patients underwent Beyond cold light tooth whitening from May 2014 to April 2016. The patients were divided into two experimental groups according to the shade guide used. Vitapan Classical shade guide was used to judge whitening effect in one group, and Vita Bleachedguide 3DMaster shade guide was used in another. Shade matching was carried out before and after whitening in both the two groups, and the results were recorded by digital photographs. Shade matching procedures were carried out by two doctors independently. If they chose the same tab, it would be seen as the shade matching result; While if they chose different tabs, another doctor would be invited to make a decision. Photographs were taken in preset conditions: intraoral photos of the full dentition in the front, and the proportion of shooting was 1:3; aperture was F22; shutter speed was 1/200; intensity of flash was M/8; ISO value was 200. The photographs were analyzed by Photoshop software. Chromatic values were measured, and color difference values were calculated. Measuring of chromatic values was carried out by three doctors independently, and all the photos were measured twice by each doctor. Six measure results of each photo were recorded, and the maximum and the minimum were excluded, then the mean was seen as the final result. The color difference values were compared by independent-sample t test. Besides, changes of shade tabs after whitening in the two groups were recorded. Color difference value was 5.06±1.71 in Vitapan Classical group, and 3.39±1.36 in Vita Bleachedguide 3D-Master group. There was statistically significant difference between the two groups (t=4.68,P<0.001). Change of shade tabs was 3.63

  1. 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.

  2. Effect of tooth whitening strips on fatigue resistance and flexural strength of bovine dentin in vitro

    PubMed Central

    Kim, Namhee; De Souza, Grace M.

    2017-01-01

    Objective To determine the effects of whitening strips on bovine dentin fatigue resistance and flexural strength in vitro. Materials and methods A total of eighty bovine dentin specimens (2x2x17mm) were treated with either: control glycerine gel on plastic film wrap or whitening strips containing 9.5% hydrogen peroxide. Treatment was applied for 30 minutes, twice a day, for 1- or 4-weeks. After the last treatment, ten specimens per group were randomly selected to undergo fatigue testing (106 cycles, 3Hz, 20N) while the other ten were subjected to flexural strength testing after ten days of storage in artificial saliva. Kaplan-Meier method with a log rank test, Wilcoxon test and Cox regression were used to assess fatigue test results (p<0.05). One-way ANOVA and Tukey’s tests were used to compare the flexural strength results (p<0.05). Results There were significant differences in survival during the fatigue test among the groups (p<0.001). Treatment (control or bleach) was a significant factor for specimen survival (p<0.001, Exp(B) = 33.45). There were significant differences in mean flexural strength (p<0.001). No significant difference was found between “1-wk control” and “4-wk control”. The mean flexural strength and fatigue resistance of the “4-wk bleach” were significantly lower than all the other groups. Conclusions The use of whitening strips reduced the fatigue resistance and flexural strength of bovine dentin in vitro. Until the effect of whitening strips on mechanical properties of human dentin is fully elucidated, it remains prudent to advise patients to avoid excessive direct use of whitening strips on dentin. PMID:28278191

  3. Relationship between arsenic skin lesions and the age of natural menopause

    PubMed Central

    2014-01-01

    Background Chronic exposure to arsenic is associated with neoplastic, cardiovascular, endocrine, neuro-developmental disorders and can have an adverse effect on women’s reproductive health outcomes. This study examined the relationship between arsenic skin lesions (a hallmark sign of chronic arsenic poisoning) and age of natural menopause (final menopausal period) in populations with high levels of arsenic exposure in Bangladesh. Methods We compared menopausal age in two groups of women – with and without arsenic skin lesions; and presence of arsenic skin lesions was used as an indicator for chronic arsenic exposure. In a cross-sectional study, a total of 210 participants were randomly identified from two ongoing studies— participants with arsenic skin lesions were identified from an ongoing clinical trial and participants with no arsenic skin lesions were identified from an ongoing cohort study. Mean age of menopause between these two groups were calculated and compared. Multivariable linear regression was used to estimate the relationship between the status of the arsenic skin lesions and age of natural menopause in women. Results Women with arsenic skin lesions were 1.5 years younger (p <0.001) at the time of menopause compared to those without arsenic skin lesions. After adjusting with contraceptive use, body mass index, urinary arsenic level and family history of premature menopause, the difference between the groups’ age at menopause was 2.1 years earlier (p <0.001) for respondents with arsenic skin lesions. Conclusions The study showed a statistically significant association between chronic exposure to arsenic and age at menopause. Heavily exposed women experienced menopause two years earlier than those with lower or no exposure. PMID:24886424

  4. [Research on the designing method of a special shade guide for tooth whitening].

    PubMed

    Xu, Yingxin

    2015-10-01

    To investigate a method of designing an accurate and scientific shade guide, especially used for judging the effect of tooth whitening, by analyzing the colorimetric values of discolored teeth statistically. One hundred thirty-six pictures of patients who had been receiving the Beyond cold light whitening treatment from February 2009 to July 2014 were analyzed, including 25 tetracycline teeth, 61 mottled-enamel teeth, and 50 yellow teeth. The colorimetric values of discolored teeth were measured. The L* values of shade tabs were calculated by hierarchical clustering of those of discolored teeth. The a* and b* values of shade tabs were the mean of those observed for discolored teeth. Accordingly, different shade guides were designed for each type of discolored teeth, and the effects were evaluated. A statistically significant difference in colorimetric values was found among the three types of discolored teeth. Compared with the Vitapan Classical shade guide, the shade guides designed through the present method were more scientific and accurate in judging the effect of tooth whitening. Moreover, the arrangement of shade tabs was more logical, and the color difference between shade tabs and discolored teeth was smaller. The proposed designing method is theoretically feasible, although its clinical effect has yet to be proven.

  5. Role of fluoridated carbamide peroxide whitening gel in the remineralization of demineralized enamel: An in vitro study.

    PubMed

    Bollineni, Swetha; Janga, Ravi Kumar; Venugopal, L; Reddy, Indukuri Ravikishore; Babu, P Ravisekhar; Kumar, Sunil S

    2014-05-01

    The use of self-administered carbamide peroxide bleaching gels has become increasingly popular for whitening of discolored vital teeth. Studies have reported that its use may induce increased levels of sensitivity and surface roughness of the tooth due to demineralization. This study evaluates the effect of fluoride addition to the bleaching agent - its remineralizing capacity and alterations in the whitening properties. Twenty-four extracted lower third molar teeth, with the pretreatment shade determined, were taken up in the study. Each tooth was sectioned into four and labeled as groups A, B, C, and D. The tooth quadrants in group A-C were demineralized; groups A and B were treated with 10% carbamide peroxide gel (group-A without fluoride and group-B with 0.463% fluoride addition) (no further treatment was carried out for group c) group-D remained as the control. The post-treatment shade was determined. The tooth samples were sectioned (approximately 200 μm) for evaluation under a light microscope. The depth of demineralization was analyzed at five different equidistant points. Statistical analysis was carried out with t-tests, accepting ≤0.05 as significant. Addition of fluoride caused remineralization of demineralized enamel. The tooth whitening system showed that the remineralization properties did not affect the whitening properties.

  6. The use of QLF to quantify in vitro whitening in a product testing model.

    PubMed

    Pretty, I A; Edgar, W M; Higham, S M

    2001-11-24

    Professional and consumer interest in whitening products continues to increase against a background of both increased oral health awareness and demand for cosmetic procedures. In the current legal climate, few dentists are providing 'in-office' whitening treatments, and thus many patients turn to home-use products. The most common of these are the whitening toothpastes. Researchers are keen to quantify the effectiveness of such products through clinically relevant trials. Previous studies examining whitening products have employed a variety of stained substrates to monitor stain removal. This study aimed to quantify the removal of stain from human enamel using a new device, quantitative light-induced fluorescence (QLF). The experimental design follows that of a product-testing model. A total of 11 previously extracted molar teeth were coated with transparent nail varnish leaving an exposed window of enamel. The sound, exposed enamel was subject to a staining regime of human saliva, chlorhexidine and tea. Each of the eleven teeth was subjected to serial exposures of a positive control (Bocasan), a negative control (water) and a test product (Yotuel toothpaste). Following each two-minute exposure QLF images of the teeth were taken (a total of 5 applications). Following completion of one test solution, the teeth were cleaned, re-stained and the procedure repeated with the next solution. QLF images were stored on a PC and analysed by a blinded single examiner. The deltaQ value at 5% threshold was reported. ANOVA and paired t-tests were used to analyse the data. The study confirmed the ability of QLF to longitudinally quantify stain reduction from human enamel. The reliability of the technique in relation to positive and negative test controls was proven. The positive control had a significantly (alpha = 0.05) higher stain removal efficacy than water (p = 0.023) and Yotuel (p = 0.046). Yotuel was more effective than water (p = 0.023). The research community, the

  7. A study of hydrogen peroxide chemistry and photochemistry in tea stain solution with relevance to clinical tooth whitening.

    PubMed

    Young, Nigel; Fairley, Peter; Mohan, Veena; Jumeaux, Coline

    2012-12-01

    Tooth whitening using hydrogen peroxide is a complex process, and there is still some controversy about the roles of pH, temperature, chemical activators, and the use of light irradiation. In this work the basic interactions between whitening agents and stain molecules are studied in simple solutions, thus avoiding the physics of diffusion and light penetration in the tooth to give clarity on the basic chemistry which is occurring. The absorbance of tea stain solution at 450 nm was measured over a period of 40 min, with various compositions of whitening agent added (including hydrogen peroxide, ferrous gluconate and potassium hydroxide) and at the same time the samples were subjected to blue light (465 nm) or infra-red light (850 nm) irradiation, or alternatively they were heated to 37°C. It is shown that the reaction rates between chromogens in the tea solution and hydrogen peroxide can be accelerated significantly using ferrous gluconate activator and blue light irradiation. Infra red irradiation does not increase the reaction rate through photochemistry, it serves only to increase the temperature. Raising the temperature leads to inefficiency through the acceleration of exothermic decomposition reactions which produce only water and oxygen. By carrying out work in simple solution it was possible to show that ferrous activators and blue light irradiation significantly enhance the whitening process, whereas infra red irradiation has no significant effect over heating. The importance of controlling the pH within the tooth structure during whitening is also demonstrated. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. [Determination of eleven fluorescent whitening agents in paper food packaging materials by UPLC-FLD/PDA with series double-detector].

    PubMed

    Wang, Tianjiao; Wu, Pinggu; Hu, Zhengyan; Wang, Liyuan; Tang, Jun; Jiang, Wei; Wang, Zhiyuan

    2016-07-01

    To establish a new qualitative and quantitative ultraperformance liquid chromatography-fluorescence detector / photodiode array detector with series double-detector method for the determination of eleven fluorescent whitening agents in paper food packaging materials. The sample was extracted with 40%acetonitrile water solution, separated by Waters ACQUITY UPLC BEH C_(18)column( 1. 7μm, 2. 1 mm × 100 mm) and eluted gradient. The excitation wavelength and emission wavelength of fluorescence detector( FLD) were 350 nm and 430 nm, and the wavelength of photodiode array detector( PDA) was 350 nm. The detectors were used in series to achieve qualitative and quantitative detection. In the substrates of paper cups, paper bowls, paper trays and paper boxes, those eleven fluorescent whitening agents were separated properly. For both detectors, in the linear range of 25- 1000 ng / m L, the correlation coefficient was greater than 0. 99, and the recoveries of spiked recoveries were between 82. 2%- 104. 1% with the RSD less than 10%( n = 6). The detection limits ofthose eleven fluorescent whitening agents were 0. 20- 0. 28 mg / kg for FLD and 1. 4- 2. 5mg / kg for PDA. The eleven fluorescent whitening agents could be separated properly with complete separation, good shapes and high recovery rate. This method is easy to operate also. Thus it's an effective method to detect the fluorescent whitening agents in paper food packaging materials.

  9. Efficacy of different whitening modalities on bovine enamel and dentin.

    PubMed

    Wiegand, Annette; Vollmer, Doreen; Foitzik, Magdalena; Attin, Rengin; Attin, Thomas

    2005-06-01

    Previous studies have shown that bleaching treatment may be efficient in both enamel and dentin, but it is still unknown how much the subsurface dentin contributes to the color change of teeth. This in vitro study evaluated the whitening effect of different external bleaching agents on enamel-dentin slabs and subsurface dentin. Ninety bovine teeth were distributed among six groups (A, Opalescence 10%; B, Opalescence PF 15%; C, Opalescence Quick; D, Opalescence Extra Boost; E, Rapid White; F, Whitestrips). Two enamel-dentin specimens were prepared from the labial surface of each teeth. In one of the specimens enamel was removed, resulting in a dentin (CD) disc of 1 mm high. The labial and the pulpal sides of the second specimen were ground until the remaining enamel and dentin layers of the enamel-dentin sample (ED) were 1 mm each. Whitening treatment of the ED specimens was performed according to manufacturers' instructions. Pre- and posttreatment Lab values of ED samples were analyzed using CIE-Lab. Baseline Lab values of dentin were analyzed by evaluation of the CD specimen. Finally, enamel of the ED specimens was removed and color change of the exposed dentin (D) was recorded. For all treatment agents significant color changes (DeltaE) were observed for enamel-dentin samples and subsurface dentin specimens compared to controls. In groups A-D DeltaE was significantly higher in dentin than enamel-dentin. Furthermore, L and b values of bleached enamel-dentin and subsurface dentin samples differed significantly from baseline. Treatment with the tested external whitening bleaching agents resulted in color change of both enamel-dentin and subsurface dentin samples. The results indicate that color change of treated teeth might be highly influenced by color change of the subsurface dentin.

  10. Revertant mosaicism in heritable skin diseases: mechanisms of natural gene therapy.

    PubMed

    Pasmooij, Anna M G; Jonkman, Marcel F; Uitto, Jouni

    2012-09-01

    Revertant mosaicism (RM) refers to the co-existence of cells carrying disease-causing mutations with cells in which the inherited mutation is genetically corrected by a spontaneous event. It has been discovered in an increasing number of heritable skin diseases: ichthyosis with confetti and different subtypes of epidermolysis bullosa. This "natural gene therapy" phenomenon manifests as normal appearing skin areas surrounded by affected skin. Although initially thought to be rare, RM is now considered relatively common in genetic skin diseases. To address the issues relevant to RM, we here discuss the following questions: 1) What is the incidence of RM in heritable skin diseases? 2) What are the repair mechanisms in RM? 3) When do the revertant mutations occur? 4) How do you recognize revertant skin? 5) Do the areas of RM change in size? The answers to these questions allow us to acquire knowledge on these reverted cells, the mechanisms of RM, and utility of the reverted cells to the advantage of the patient. The revertant skin could potentially be used to treat the patient's own affected skin.

  11. Enhancing blood donor skin disinfection using natural oils.

    PubMed

    Alabdullatif, Meshari; Boujezza, Imen; Mekni, Mohamed; Taha, Mariam; Kumaran, Dilini; Yi, Qi-Long; Landoulsi, Ahmed; Ramirez-Arcos, Sandra

    2017-12-01

    Effective donor skin disinfection is essential in preventing bacterial contamination of blood components with skin flora bacteria like Staphylococcus epidermidis. Cell aggregates of S. epidermidis (biofilms) are found on the skin and are resistant to the commonly used donor skin disinfectants chlorhexidine-gluconate and isopropyl alcohol. It has been demonstrated that essential oils synergistically enhance the antibacterial activity of chlorhexidine-gluconate. The objective of this study was to test plant-extracted essential oils in combination with chlorhexidine-gluconate or chlorhexidine-gluconate plus isopropyl alcohol for their ability to eliminate S. epidermidis biofilms. The composition of oils extracted from Artemisia herba-alba, Lavandula multifida, Origanum marjoram, Rosmarinus officinalis, and Thymus capitatus was analyzed using gas chromatography-mass spectrometry. A rabbit model was used to assess skin irritation caused by the oils. In addition, the anti-biofilm activity of the oils used alone or in combination with chlorhexidine-gluconate or chlorhexidine-gluconate plus isopropyl alcohol was tested against S. epidermidis biofilms. Essential oil concentrations 10%, 20%, and 30% were chosen for anti-biofilm assays, because skin irritation was observed at concentrations greater than 30%. All oils except for O. marjoram had anti-biofilm activity at these three concentrations. L. multifida synergistically enhanced the anti-biofilm activity of chlorhexidine-gluconate and resulted in the highest anti-biofilm activity observed when combined with chlorhexidine-gluconate plus isopropyl alcohol. Gas chromatography-mass spectrometry revealed that the main component contributing to the activity of L. multifida oil was a natural terpene alcohol called linalool. The anti-biofilm activity of chlorhexidine-gluconate plus isopropyl alcohol can be greatly enhanced by L. multifida oil or linalool. Therefore, these components could potentially be used to improve blood

  12. An in vivo study of the effect of a 38 percent hydrogen peroxide in-office whitening agent on enamel.

    PubMed

    Cadenaro, Milena; Navarra, Chiara Ottavia; Mazzoni, Annalisa; Nucci, Cesare; Matis, Bruce A; Di Lenarda, Roberto; Breschi, Lorenzo

    2010-04-01

    In an in vivo study, the authors tested the hypothesis that no difference in enamel surface roughness is detectable either during or after bleaching with a high-concentration in-office whitening agent. The authors performed profilometric and scanning electron microscopic (SEM) analyses of epoxy resin replicas of the upper right incisors of 20 participants at baseline (control) and after each bleaching treatment with a 38 percent hydrogen peroxide whitening agent, applied four times, at one-week intervals. The authors used analysis of variance for repeated measures to analyze the data statistically. The profilometric analysis of the enamel surface replicas after the in vivo bleaching protocol showed no significant difference in surface roughness parameters (P > .05) compared with those at baseline, irrespective of the time interval. Results of the correlated SEM analysis showed no relevant alteration on the enamel surface. Results of this in vivo study support the tested hypothesis that the application of a 38 percent hydrogen peroxide in-office whitening agent does not alter enamel surface roughness, even after multiple applications. The use of a 38 percent hydrogen peroxide in-office whitening agent induced no roughness alterations of the enamel surface, even after prolonged and repeated applications.

  13. Virtually Naked: Virtual Environment Reveals Sex-Dependent Nature of Skin Disclosure

    PubMed Central

    Lomanowska, Anna M.; Guitton, Matthieu J.

    2012-01-01

    The human tendency to reveal or cover naked skin reflects a competition between the individual propensity for social interactions related to sexual appeal and interpersonal touch versus climatic, environmental, physical, and cultural constraints. However, due to the ubiquitous nature of these constraints, isolating on a large scale the spontaneous human tendency to reveal naked skin has remained impossible. Using the online 3-dimensional virtual world of Second Life, we examined spontaneous human skin-covering behavior unhindered by real-world climatic, environmental, and physical variables. Analysis of hundreds of avatars revealed that virtual females disclose substantially more naked skin than virtual males. This phenomenon was not related to avatar hypersexualization as evaluated by measurement of sexually dimorphic body proportions. Furthermore, analysis of skin-covering behavior of a population of culturally homogeneous avatars indicated that the propensity of female avatars to reveal naked skin persisted despite explicit cultural norms promoting less revealing attire. These findings have implications for further understanding how sex-specific aspects of skin disclosure influence human social interactions in both virtual and real settings. PMID:23300580

  14. Virtually naked: virtual environment reveals sex-dependent nature of skin disclosure.

    PubMed

    Lomanowska, Anna M; Guitton, Matthieu J

    2012-01-01

    The human tendency to reveal or cover naked skin reflects a competition between the individual propensity for social interactions related to sexual appeal and interpersonal touch versus climatic, environmental, physical, and cultural constraints. However, due to the ubiquitous nature of these constraints, isolating on a large scale the spontaneous human tendency to reveal naked skin has remained impossible. Using the online 3-dimensional virtual world of Second Life, we examined spontaneous human skin-covering behavior unhindered by real-world climatic, environmental, and physical variables. Analysis of hundreds of avatars revealed that virtual females disclose substantially more naked skin than virtual males. This phenomenon was not related to avatar hypersexualization as evaluated by measurement of sexually dimorphic body proportions. Furthermore, analysis of skin-covering behavior of a population of culturally homogeneous avatars indicated that the propensity of female avatars to reveal naked skin persisted despite explicit cultural norms promoting less revealing attire. These findings have implications for further understanding how sex-specific aspects of skin disclosure influence human social interactions in both virtual and real settings.

  15. 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.

  16. Calcium release rates from tooth enamel treated with dentifrices containing whitening agents and abrasives.

    PubMed

    Araujo, Danilo Barral; Silva, Luciana Rodrigues; de Araujo, Roberto Paulo Correia

    2010-01-01

    Tooth whitening agents containing hydrogen peroxide and carbamide peroxide are used frequently in esthetic dental procedures. However, lesions on the enamel surface have been attributed to the action of these products. Using conventional procedures for separating and isolating biological structures, powdered enamel was obtained and treated with hydrogen peroxide, carbamide peroxide, and sodium bicarbonate, ingredients typically found in dentifrices. The enamel was exposed to different pH levels, and atomic emission spectrometry was used to determine calcium release rates. As the pH level increased, the rate of calcium release from enamel treated with dentifrices containing whitening agents decreased. Carbamide peroxide produced the lowest amount of decalcification, while sodium bicarbonate produced the highest release rates at all pH levels.

  17. The amelioration effect of tranexamic acid in wrinkles induced by skin dryness.

    PubMed

    Hiramoto, Keiichi; Sugiyama, Daijiro; Takahashi, Yumi; Mafune, Eiichi

    2016-05-01

    Tranexamic acid (trans-4-aminomethylcyclohexanecarboxylic acid) is a medical amino acid widely used as an anti-inflammatory and a whitening agent. This study examined the effect of tranexamic acid administration in wrinkle formation following skin dryness. We administered tranexamic acid (750mg/kg/day) orally for 20 consecutive days to Naruto Research Institute Otsuka Atrichia (NOA) mice, which naturally develop skin dryness. In these NOA mice, deterioration of transepidermal water loss (TEWL), generation of wrinkles, decrease of collagen type I, and increases in mast cell proliferation and tryptase and matrix metalloproteinase (MMP-1) release were observed. However, these symptoms were improved by tranexamic acid treatment. Moreover, the increase in the β-endorphin level in the blood and the expression of μ-opioid receptor on the surface of fibroblasts increased by tranexamic acid treatment. In addition, when the fibroblasts induced by tranexamic acid treatment were removed, the amelioration effect by tranexamic acid treatment was halved. On the other hand, tranexamic acid treated NOA mice and mast cell removal in tranexamic acid treated NOA mice did not result in changes in the wrinkle amelioration effect. Additionally, the amelioration effect of mast cell deficient NOA mice was half that of tranexamic acid treated NOA mice. These results indicate that tranexamic acid decreased the proliferation of mast cells and increases the proliferation of fibroblasts, subsequently improving wrinkles caused by skin dryness. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  18. [Perivenular whitening in central retinal vein occlusion demonstrated by "en-face" OCT].

    PubMed

    Marc, C; Gire, J; Boulicot, C; Guigou, S

    2013-10-01

    We report the case of a patient with a central vein occlusion associated with perivenular whitening. The "en-face" spectral domain OCT precisely demonstrated the ischemic area. This case underscores the utility of the "en-face" mode in the follow-up CRVO. Copyright © 2013. Published by Elsevier Masson SAS.

  19. An Innovations-Based Noise Cancelling Technique on Inverse Kepstrum Whitening Filter and Adaptive FIR Filter in Beamforming Structure

    PubMed Central

    Jeong, Jinsoo

    2011-01-01

    This paper presents an acoustic noise cancelling technique using an inverse kepstrum system as an innovations-based whitening application for an adaptive finite impulse response (FIR) filter in beamforming structure. The inverse kepstrum method uses an innovations-whitened form from one acoustic path transfer function between a reference microphone sensor and a noise source so that the rear-end reference signal will then be a whitened sequence to a cascaded adaptive FIR filter in the beamforming structure. By using an inverse kepstrum filter as a whitening filter with the use of a delay filter, the cascaded adaptive FIR filter estimates only the numerator of the polynomial part from the ratio of overall combined transfer functions. The test results have shown that the adaptive FIR filter is more effective in beamforming structure than an adaptive noise cancelling (ANC) structure in terms of signal distortion in the desired signal and noise reduction in noise with nonminimum phase components. In addition, the inverse kepstrum method shows almost the same convergence level in estimate of noise statistics with the use of a smaller amount of adaptive FIR filter weights than the kepstrum method, hence it could provide better computational simplicity in processing. Furthermore, the rear-end inverse kepstrum method in beamforming structure has shown less signal distortion in the desired signal than the front-end kepstrum method and the front-end inverse kepstrum method in beamforming structure. PMID:22163987

  20. Determination of demineralization depth in tooth enamel exposed to abusive use of whitening gel using micro-Energy Dispersive X ray Fluorescence

    NASA Astrophysics Data System (ADS)

    Pessanha, Sofia; Coutinho, Sara; Carvalho, Maria Luisa; Silveira, João Miguel; Mata, António

    2017-12-01

    In this work, we present a methodology for the determination of the depth of demineralization in dental enamel caused by extended use of an Over-The-Counter (OTC) whitening product. Teeth whitening is a very common practice in Dentistry, but concerns have been raised regarding the invasiveness of the treatment, especially regarding OTC products, that can be used without medical supervision and sometimes with concentrations of active agent that exceed the allowed regulations. In this work, we studied tooth enamel samples, treated with a whitening product during an extended period of time, both directly on the enamel surface and in the cross-section. Specimens were analyzed using microbeam X-Ray Fluorescence (micro-XRF) using polycapillary optics to obtain a spot down to 25 μm. Due to the relatively large spot size of our setup point analysis of the cross-sections would be inadequate. This way, line scans were performed instead, before and after whitening, and using appropriate data treatment the depth of demineralization was inferred. The used methodology indicated an average demineralization depth of 25 μm, the same order of magnitude as the aprismatic enamel layer.

  1. Effect of whitening dentifrices on the surface roughness of a nanohybrid composite resin

    PubMed Central

    da Rosa, Gabriela Migliorin; da Silva, Luciana Mendonça; de Menezes, Márcio; do Vale, Hugo Felipe; Regalado, Diego Ferreira; Pontes, Danielson Guedes

    2016-01-01

    Objectives: The present study verified the influence of whitening dentifrices on the surface roughness of a nanohybrid composite resin. Materials and Methods: Thirty-two specimens were prepared with Filtek™ Z350 XT (3M/ESPE) and randomly divided into four groups (n = 08) that were subjected to brushing simulation equivalent to the period of 1 month. The groups assessed were a control group with distilled water (G1), Colgate Total 12 Professional Clean (G2), Sensodyne Extra Whitener Extra Fresh (G3), and Colgate Luminous White (G4). A sequence of 90 cycles was performed for all the samples. The initial roughness of each group was analyzed by the Surface Roughness Tester (TR 200-TIME Group Inc., CA, USA). After the brushing period, the final roughness was measured, and the results were statistically analyzed using nonparametric Kruskal–Wallis and Dunn tests for intergroup roughness comparison in the time factor. For intragroup and “Δ Final − Initial” comparisons, the Wilcoxon test and (one-way) ANOVA were, respectively, performed (α = 0.05). Results: The roughness mean values before and after brushing showed no statistically significant difference when the different dentifrices were used. None of the dentifrices analyzed increased significantly the nanohybrid composite resin surface roughness in a 1 month of tooth brushing simulation. Conclusions: These results suggest that no hazardous effect on the roughness of nanohybrid composite resin can be expected when whitening dentifrices are used for a short period. Similar studies should be conducted to analyze other esthetic composite materials. PMID:27095891

  2. Placebo-controlled clinical trial of use of 10% hydrogen peroxide whitening strips for medication-induced xerostomia.

    PubMed

    Papas, Athena S; Kugel, Gerard; Singh, Mabi; Barker, Matthew L; Gerlach, Robert W

    2009-01-01

    A randomized, double-blind, placebo-controlled clinical trial was conducted to evaluate the effectiveness and safety of peroxide-containing strip-based tooth whitening among subjects with medication-induced hyposalivation. Eligibility for this tooth whitening study was limited to dentate adults taking xerogenic medications with an unstimulated salivary flow < or = 0.2 ml/min. After giving informed consent, 42 subjects were randomized using a 2:1 ratio to 10% hydrogen peroxide whitening strips (Crest Whitestrips Premium) or placebo strips without peroxide. Strips were used for 30 min twice daily for a 14-day period. Usage was unsupervised, and only the maxillary arch was treated. On days 8 and 15, efficacy was assessed from standard digital images of the anterior dentition and quantified using the Cielab color system, while safety was assessed from interviews and clinical examinations. At day 8, the peroxide group experienced significant (p < 0.001) color improvement relative to baseline and placebo. Adjusted means +/- standard errors for yellowness reduction were -1.65 +/- 0.115 units for the peroxide group and -0.32 +/- 0.170 units for the placebo group. For the increase in lightness, adjusted means +/- standard errors on day 8 were 1.53 +/- 0.130 units for the peroxide group and 0.37 +/- 0.191 units for the controls. Continued strip use through day 15 yielded incremental color improvement for the peroxide group. Mild and transient tooth sensitivity represented the most common adverse events. No subject discontinued treatment due to a product-related adverse event. Twice daily use of 10% hydrogen peroxide whitening strips by adults with medication-induced xerostomia was well tolerated, with significant tooth color improvement evident within 7 days. Copyright 2009 S. Karger AG, Basel.

  3. Effective of diode laser on teeth enamel in the teeth whitening treatment

    NASA Astrophysics Data System (ADS)

    Klunboot, U.; Arayathanitkul, K.; Chitaree, R.; Emarat, N.

    2011-12-01

    This research purpose is to investigate the changing of teeth color and to study the surface of teeth after treatment by laser diode at different power densities for tooth whitening treatment. In the experiment, human-extracted teeth samples were divided into 7 groups of 6 teeth each. After that laser diode was irradiated to teeth, which were coated by 38% concentration of hydrogen peroxide, during for 20, 30 and 60 seconds at power densities of 10.9 and 52.1 W/cm2. The results of teeth color change were described by the CIEL*a*b* systems and the damage of teeth surface were investigated by scanning electron microscopy (SEM). The results showed that the power density of the laser diode could affect the whiteness of teeth. The high power density caused more luminous teeth than the low power density did, but on the other hand the high power density also caused damage to the teeth surface. Therefore, the laser diode at the low power densities has high efficiency for tooth whitening treatment and it has a potential for other clinical applications.

  4. The measurement of enamel and dentine abrasion by tooth whitening products using an in situ model.

    PubMed

    Joiner, A; Collins, L Z; Cox, T F; Pickles, M J; Weader, E; Liscombe, C; Holt, J S

    2005-01-01

    To determine the enamel and dentine wear of two whitening toothpastes using an in situ model with ex vivo brushing. Human enamel/dentine (approximately 50:50) blocks (approximately 4 x 4mm) were placed in the upper buccal aspects of full or partial dentures of a group of 25 subjects. Subjects brushed the specimens ex vivo with either a calcium carbonate/perlite or silica containing whitening toothpaste under exaggerated conditions as compared to normal for 30 s, twice per day. Specimens were removed after 4, 8 and 12 weeks and the wear to the enamel and dentine was determined. Enamel wear was determined by change in Knoop indent length and dentine wear was determined from the enamel-dentine step height, measured using optical profilometry. The mean wear after 12 weeks was for enamel 0.27 and 0.19 microns, and for dentine 34.3 and 61.1 microns, for the calcium carbonate/perlite and silica toothpastes respectively. There were no significant differences between products after 12 weeks. The rate of wear was found to decrease throughout the duration of the study. There were no significant differences between the two whitening toothpastes in terms of enamel and dentine wear after 12 weeks brushing.

  5. Comparison of the Effects of Two Whitening Toothpastes on Microhardness of the Enamel and a Microhybride Composite Resin: An in Vitro Study

    PubMed Central

    Khamverdi, Z.; Kasraie, Sh.; Rezaei-Soufi, L.; Jebeli, S.

    2010-01-01

    Introduction: Whitening toothpastes which have been accepted in populations may affect properties of enamel and restorative materials. The aim of this study was to compare the microhardness of human enamel and Z250 microhybrid composite resin after brushing with two whitening toothpastes. Materials and Methods: In this experimental study of enamel specimens, forty five freshly extracted human incisors were prepared and divided into three groups of control enamel (ClE), Crest enamel (CtE) and Aquafresh enamel (AfE). For composite resin specimens, forty five cylindrical-shaped specimens of light-cured Z250 composite were prepared and divided into three groups of control composite (ClC), Crest composite (CtC) and Aquafresh composite (AfC). The control groups were brushed without toothpaste. Crest and Aquafresh group specimens were brushed with Crest and Aquafresh whitening toothpastes, respectively. Vickers microhardness test was performed for all groups. Data were analyzed by One-way ANOVA and Tukey tests. Results: Microhardness values of ClE, CtE, AfE, ClC, CtC and AfC groups were 332.99 ± 26.59, 313.99 ± 20.56, 323.57 ± 27.96, 137.1 ± 3.16, 122.95 ± 3.27 and 130.36 ± 4.8, respectively. One-way ANOVA showed no significant differences among three enamel groups but there was significant difference among composite groups (p<0.01). Conclusion: Crest and Aquafresh whitening toothpastes did not affect enamel hardness but reduced the microhardness value of Z-250 composite resin. However, Crest whitening toothpaste decreased the microhardness more than Aquafresh. PMID:21998788

  6. Effects of tooth whitening and orange juice on surface properties of dental enamel.

    PubMed

    Ren, Yan-Fang; Amin, Azadeh; Malmstrom, Hans

    2009-06-01

    To study the effects of 6% H2O2 activated with LED light on surface enamel as compared to orange juice challenges in vitro. A total of 40 human enamel discs were incubated in saliva overnight to allow pellicle formation and then divided into three groups: 15 for whitening treatments, 15 for orange juice immersions and 10 for normal saline controls. Baseline microhardness was measured with a microhardness Knoop indenter (50g, 10s) and surface topography was evaluated with a focus-variation 3D scanning microscopy. Enamel discs were treated with H2O2 or orange juice for 20 min each cycle for five cycles to simulate daily treatment with the products for 5 days. The discs were stored in saliva between treatment cycles. Microhardness and surface topography were evaluated again after treatments. Changes in microhardness and in surface area roughness (Sa), mean maximum peak-to-valley distance (Sz) and the developed surface area ratio (Sdr) were compared before and after treatments (t-test) and among groups (ANOVA). Enamel surface hardness decreased by 84% after orange juice immersion but no statistically significant changes were observed in the whitening and control groups. Surface topography changed significantly only in the orange juice group as shown by increased Sa (1.2 microm vs. 2.0 microm), Sz (7.7 microm vs. 10.2 microm) and Sdr (2.8% vs. 6.0%). No such changes were observed in the whitening and control groups. In comparison to orange juice challenges, the effects of 6% H2O2 on surface enamel are insignificant. Orange juice erosion markedly decreased hardness and increased roughness of enamel.

  7. Skin and skeletal system lesions of european pond turtles (Emys orbicularis) from natural habitats.

    PubMed

    Aleksić-Kovačević, Sanja; Ozvegy, József; Krstić, Nikola; Rusvai, Miklós; Jakab, Csaba; Stanimirović, Zoran; Becskei, Zsolt

    2014-06-01

    Water pollution is known to play an important role in the pathogenesis of plastron, carapace and skin diseases of turtles. In this study, a total of 150 European pond turtles (Emys orbicularis) of different age and both sexes, originating from natural habitats in Serbia, were examined for morphological changes of the skin, plastron, carapace and skeletal system. The turtles were taken out from their natural habitats in Lake Ludas, Lake Palic and Lake Tresetiste. After artificial hibernation, they were subjected to detailed examination, sampled and treated, and finally returned into their natural habitat. Biopsies from the skin and shell were subjected to histopathological examination and microbiological analysis. X-ray scanning was also performed to detect changes in the skeletal system. Macroscopic changes of the skin, most frequently degenerative, inflammatory or neoplastic diseases, were diagnosed in 49.33% of the turtles examined. Dermatitis of different origin and form was the most prominent histopathological finding (28.00%). In the plastron, inflammatory and degenerative processes were frequently found. Osteopathy and mechanical injuries were the dominant findings. Macroscopic changes of the plastron, carapace and skeletal system were diagnosed in 67.33% of the turtles examined. Using X-ray scanning, generalised osteopathy, anomalies and malformations of different aetiology were also diagnosed on the tail and legs. Microbiological examinations showed the presence of a variety of bacterial and fungal agents, either primary pathogens or potential polluters, which invaded the skin and shell, or were present in cloacal swab samples. Bacterial infection was diagnosed in 76.66% of the turtles, first of all in those with skin and shell necrosis. Mycoses were diagnosed in 33.33% of the animals.

  8. Effect of whitening toothpastes on bonding of restorative materials to enamel of primary teeth.

    PubMed

    Abdelmegid, F Y

    2016-01-01

    The aim of this in vitro investigation was to measure shear bond strength (SBS) of a resin composite and a resin-modified glass ionomer to enamel of primary teeth after application of different whitening toothpastes (WTs). Eighty labial enamel surfaces of primary incisors were randomly distributed into 8 groups of 10 each according to the surface treatment and bonding material. G1 and G2, control (brushed with water without WT); G3 and G4, (brushed with Colgate Optic White WT [Colgate-Palmolive Company, New York, NY, USA]), G5 and G6, (brushed with Crest Pro-Health Whitening WT [Procter and Gamble, Cincinnati, OH, USA]) and G7 and G8, (brushed with Arm and Hammer Advance White Extreme Whitening with Stain Defense WT [Church and Dwight Co., Princeton, NJ, USA]). SBS was measured at a crosshead speed of 0.5 mm/min and the type of bond failure was assessed using a stereomicroscope. There was significant difference between SBS of composite resin in groups 1, 3, 5, and 7 (P < 0.001), but no difference between resin-modified glass ionomer in groups 2, 4, 6, and 8 (P < 0.056). SBS of group 1 (control) was greater than groups 3, 5, and 7. There was a significant difference between group 1 and group 2 as well as group 7 and group 8 (P < 0.001). WTs affect SBS of resin composite, but not resin-modified glass ionomer to enamel of primary teeth. No difference of failure modes between different groups of tested materials.

  9. Effectiveness of sodium bicarbonate combined with hydrogen peroxide and CPP-ACPF in whitening and microhardness of enamel.

    PubMed

    Ahrari, Farzaneh; Hasanzadeh, Nadia; Rajabi, Omid; Forouzannejad, Zakiyeh

    2017-03-01

    This study investigated the effects of sodium bicarbonate (NaHCO3) combined with 1.5% hydrogen peroxide (H2O2) and casein phosphopeptide amorphous calcium phosphate fluoride (CPP-ACPF) on color and microhardness of enamel. Seventy-five bovine incisors were immersed in a tea solution for 7.5 days. The specimens were randomly divided into five groups according to the whitening agent applied: 1) 94% NaHCO3, 2) a blend of 94% NaHCO3 and CPP-ACPF, 3) a blend of 94% NaHCO3 and 1.5% H2O2, 4) a blend of 94% NaHCO3, 1.5% H2O2 and CPP-ACPF, 5) control. The whitening procedure was performed for 10 times over 10 days. At each day, the buccal surfaces were covered with whitening agents for 5 minutes and then brushed for 30 seconds. After the 10 days, the teeth were again immersed in a tea solution for 10 minutes. Color assessment was performed at baseline (T1), after the first staining process (T2), after the whitening procedure (T3), and after the second staining process (T4). Finally, the specimens were subjected to microhardness test. There was a statistically significant difference in the color change between T2 and T3 stages among the study groups ( p <0.05), with the greatest improvement observed in group 4. Microhardness was significantly greater in groups 2 and 4, as compared to the other groups ( p <0.05). The combination of 94% NaHCO3, 1.5% H2O2 and CPP-ACPF was effective in improving color and microhardness of teeth with extrinsic stains and could be recommended in the clinical situation.

  10. Effectiveness of sodium bicarbonate combined with hydrogen peroxide and CPP-ACPF in whitening and microhardness of enamel

    PubMed Central

    Hasanzadeh, Nadia; Rajabi, Omid; Forouzannejad, Zakiyeh

    2017-01-01

    Background This study investigated the effects of sodium bicarbonate (NaHCO3) combined with 1.5% hydrogen peroxide (H2O2) and casein phosphopeptide amorphous calcium phosphate fluoride (CPP-ACPF) on color and microhardness of enamel. Material and Methods Seventy-five bovine incisors were immersed in a tea solution for 7.5 days. The specimens were randomly divided into five groups according to the whitening agent applied: 1) 94% NaHCO3, 2) a blend of 94% NaHCO3 and CPP-ACPF, 3) a blend of 94% NaHCO3 and 1.5% H2O2, 4) a blend of 94% NaHCO3, 1.5% H2O2 and CPP-ACPF, 5) control. The whitening procedure was performed for 10 times over 10 days. At each day, the buccal surfaces were covered with whitening agents for 5 minutes and then brushed for 30 seconds. After the 10 days, the teeth were again immersed in a tea solution for 10 minutes. Color assessment was performed at baseline (T1), after the first staining process (T2), after the whitening procedure (T3), and after the second staining process (T4). Finally, the specimens were subjected to microhardness test. Results There was a statistically significant difference in the color change between T2 and T3 stages among the study groups (p<0.05), with the greatest improvement observed in group 4. Microhardness was significantly greater in groups 2 and 4, as compared to the other groups (p<0.05). Conclusions The combination of 94% NaHCO3, 1.5% H2O2 and CPP-ACPF was effective in improving color and microhardness of teeth with extrinsic stains and could be recommended in the clinical situation. PMID:28298972

  11. Automated model selection in covariance estimation and spatial whitening of MEG and EEG signals.

    PubMed

    Engemann, Denis A; Gramfort, Alexandre

    2015-03-01

    Magnetoencephalography and electroencephalography (M/EEG) measure non-invasively the weak electromagnetic fields induced by post-synaptic neural currents. The estimation of the spatial covariance of the signals recorded on M/EEG sensors is a building block of modern data analysis pipelines. Such covariance estimates are used in brain-computer interfaces (BCI) systems, in nearly all source localization methods for spatial whitening as well as for data covariance estimation in beamformers. The rationale for such models is that the signals can be modeled by a zero mean Gaussian distribution. While maximizing the Gaussian likelihood seems natural, it leads to a covariance estimate known as empirical covariance (EC). It turns out that the EC is a poor estimate of the true covariance when the number of samples is small. To address this issue the estimation needs to be regularized. The most common approach downweights off-diagonal coefficients, while more advanced regularization methods are based on shrinkage techniques or generative models with low rank assumptions: probabilistic PCA (PPCA) and factor analysis (FA). Using cross-validation all of these models can be tuned and compared based on Gaussian likelihood computed on unseen data. We investigated these models on simulations, one electroencephalography (EEG) dataset as well as magnetoencephalography (MEG) datasets from the most common MEG systems. First, our results demonstrate that different models can be the best, depending on the number of samples, heterogeneity of sensor types and noise properties. Second, we show that the models tuned by cross-validation are superior to models with hand-selected regularization. Hence, we propose an automated solution to the often overlooked problem of covariance estimation of M/EEG signals. The relevance of the procedure is demonstrated here for spatial whitening and source localization of MEG signals. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Effect of tray-based and trayless tooth whitening systems on microhardness of enamel surface and subsurface.

    PubMed

    Teixeira, Erica C N; Ritter, André V; Thompson, Jeffrey Y; Leonard, Ralph H; Swift, Edward J

    2004-12-01

    To evaluate the effect of tray-based and trayless tooth whitening systems on surface and subsurface microhardness of human enamel. Enamel slabs were obtained from recently extracted human third molars. Specimens were randomly assigned to six groups according to tooth whitening treatment (n = 10): 6.0% hydrogen peroxide (HP) (Crest Whitestrips), 6.5% HP (Crest Professional Whitestrips), 7.5% HP (Day White Excel 3), 9.5% HP (Day White Excel 3), 10% carbamide peroxide (Opalescence), and a control group (untreated). Specimens were treated for 14 days following manufacturers' recommended protocols, and were immersed in artificial saliva between treatments. Enamel surface Knoop microhardness (KHN) was measured immediately before treatment, and at days 1, 7, and 14 of treatment. After treatment, subsurface microhardness was measured at depths of 50-500 microm. Data were analyzed for statistical significance using analysis of variance. Differences in microhardness for treated vs. untreated enamel surface were not statistically significant at any time interval. For 6.5% and 9.5% HP, there was a decrease in surface microhardness values during treatment, but at the end of treatment the microhardness values were not statistically different from the baseline values. For the enamel subsurface values, no differences were observed between treated vs. untreated specimens at each depth. Trayless and tray-based tooth whitening treatments do not significantly affect surface or subsurface enamel microhardness.

  13. The natural history of skin-limited Langerhans cell histiocytosis: a single-institution experience.

    PubMed

    Ehrhardt, Matthew J; Humphrey, Stephen R; Kelly, Michael E; Chiu, Yvonne E; Galbraith, Sheila S

    2014-11-01

    Prior reports of Langerhans cell histiocytosis (LCH) suggest that isolated skin involvement is rare and often progresses to systemic disease. More rapid access to pediatric subspecialty care has likely led to more frequent representation of this condition. The purpose of this study is to characterize the natural history of skin-limited LCH in an era of increased access to pediatric subspecialty care. A retrospective chart review was performed on all patients newly diagnosed with LCH between 2001 and 2012 at the Children's Hospital of Wisconsin. Extensive review of laboratory, physical examination, and imaging reports was performed and data collected for patients with biopsy-proven skin LCH. Sixteen individuals with skin-limited LCH were identified. The median age at onset of skin eruption was birth (range, birth to 6 mo), and median duration of follow-up was 19.5 months (range, 2 wk to 10 y) from diagnosis. One patient (6%) developed pituitary disease and 1 patient (6%) had refractory skin involvement. All others experienced complete resolution. For patients without progressive or refractory disease, resolution of skin findings occurred within 7 months from onset. Progression of skin-limited to multisystem LCH likely may be less frequent than previously described.

  14. Insights into an adipocyte whitening program

    PubMed Central

    Hill, Bradford G

    2015-01-01

    White adipose tissue plays a critical role in regulating systemic metabolism and can remodel rapidly in response to changes in nutrient availability. Nevertheless, little is known regarding the metabolic changes occurring in adipocytes during obesity. Our laboratory recently addressed this issue in a commonly used, high-fat-diet mouse model of obesity. We found remarkable changes in adipocyte metabolism that occur prior to infiltration of macrophages in expanding adipose tissue. Results of metabolomic analyses, adipose tissue respirometry, electron microscopy, and expression analyses of key genes and proteins revealed dysregulation of several metabolic pathways, loss of mitochondrial biogenetic capacity, and apparent activation of mitochondrial autophagy which were followed in time by downregulation of numerous mitochondrial proteins important for maintaining oxidative capacity. These findings demonstrate the presence of an adipocyte whitening program that may be critical for regulating adipose tissue remodeling under conditions of chronic nutrient excess. PMID:26167407

  15. Evidence for Anti-Aging South Korean Cosmeceuticals.

    PubMed

    Quay, Ellinor R; Chang, Yunyoung C; Graber, Emmy

    2017-04-01

    As the market for South Korean skin care products grows in the U.S. and worldwide, consumers will increasingly seek advice from dermatologists regarding their efficacy. In this paper, the evidence behind the anti-aging and skin whitening activity of ingredients in the most popular South Korean skin care products was reviewed and critically evaluated. Industry profit data from Euromonitor was obtained to identify the top cosmeceutical brands by retail value in South Korea. The top selling products and their ingredients were then identified from individual brand websites. A comprehensive literature search was conducted using Pubmed to identify and grade the anti-aging and whitening efficacy for nine popular ingredients: licorice, niacinamide, beta-glucan, snail mucus, ginkgo biloba, ginseng, green tea, pomegranate, and soy. Of the various ingredients reviewed, niacinamide, green tea, licorice, and soy have the most published data for anti-aging and whitening activity. Although the literature shows modest results, small sample sizes limit interpretation. High-level evidence to support the use of South Korean skin care products in anti-aging and skin whitening is lacking.

    J Drugs Dermatol. 2017;16(4):358-364.

    .

  16. Whitening and anti-wrinkle activities of ferulic acid isolated from Tetragonia tetragonioides in B16F10 melanoma and CCD-986sk fibroblast cells.

    PubMed

    Park, Hye-Jin; Cho, Jun-Hyo; Hong, Shin-Hyub; Kim, Dong-Hee; Jung, Hee-Young; Kang, In-Kyu; Cho, Young-Je

    2018-01-01

    Ferulic acid isolated from Tetragonia tetragonioides was tested for its whitening effect on the B16F10 mouse melanoma cell line and its anti-wrinkle activity on the CCD-986sk human dermal fibroblast cell line. Ferulic acid, one of the primary phenolic compounds that can be isolated from T. tetragonioides, has been reported to show potential as a functional food, for its whitening effect and anti-wrinkle activity. To measure its whitening and anti-wrinkle activities, cells were treated with ferulic acid isolated from T. tetragonioides at concentrations between 5 and 20 μM. Ferulic acid showed no cytotoxicity at concentrations up to 20 μM. Ferulic acid inhibited melanin synthesis, tyrosinase expression, and microphthalmia transcription factor expression in B16F10 cells stimulated with α-melanocyte stimulating hormone. Ferulic acid induced procollagen synthesis, hyaluronic acid synthesis, tissue inhibitor of metalloproteinase synthesis, and inhibited matrix metalloproteinase (MMP)-1 and MMP-9 expression in CCD-986sk cells stimulated with UV-B. On the basis of these results, we conclude that ferulic acid isolated from T. tetragonioides shows potential for use as a functional food, with whitening and anti-wrinkle activities.

  17. 'Honey ointment': a natural remedy of skin wound infections.

    PubMed

    Tasleem, Samiyah; Naqvi, Syed Baqir Shyum; Khan, Saadat Ali; Hashimi, Khursheed

    2011-01-01

    Honey is a gift of nature, principally identified and valued to possess antimicrobial and anti-inflammatory activity and has been used as a natural remedy of wounds since ancient times. The objectives of this study were to evaluate the antimicrobial activity of honey against micro-organisms, to formulate a honey ointment and to evaluate the efficacy of such ointment by conducting clinical trials on skin wound infection. This experimental study was conducted at Department of Pharmaceutics, Faculty of Pharmacy, University of Karachi and Out-patient Department of Dermatology, Fauji Foundation Hospital, Rawalpindi from November 2009 to October 2010. The antimicrobial activity of Pakistani floral sources (Trachysperm copticum, Acacia nilotica species indica, Zizyphus) honey samples was investigated by disc diffusion method against freshly isolated wound infecting bacteria (Staphylococci aureus, Staphylococci epidermidis, Streptococcus faecalis, Pseudomonas aeruginosa, Klebsiella pneumonia, Escherichia coli, Proteus vulgaris and Candida albicans), and Staphylococci aureus ATCC 6538, Pseudomonas aeruginosa ATCC 9022, Escherichia coli ATCC 25922, Candida albican ATCC 15146. An ointment containing 20% active antimicrobial honey was formulated. The efficacy of such ointment was evaluated by passing thought clinical trials. A total number of 27 patients (23 skin wound infection, and 4 diabetic foot ulcer) were involved in the study. Thin layer of newly formulated honey ointment on gauze were applied two to three times per day till complete healing. In microbiological assay the honey samples were found to exhibit a very promising antimicrobial activity against all the micro-organisms tested. In clinical trial very significant results (99.15%) healing was observed in skin wound infections cases with mean healing time of 5.86 (2-20) days, and 95% diabetic foot ulcers healed with the mean healing time of 20 (8-40) days. Newly formulated ointment containing 20% active

  18. Validation of Eupatorium triplinerve Vahl leaves, a skin care herb from East Kalimantan, using a melanin biosynthesis assay.

    PubMed

    Arung, Enos Tangke; Kuspradini, Harlinda; Kusuma, Irawan Wijaya; Shimizu, Kuniyoshi; Kondo, Ryuichiro

    2012-04-01

    In searching for a new material made from natural resources that could be used as a whitening agent, we focused on the plants used for skin treatment by the native people of East Kalimantan. The methanol extract of the leaves of Eupatorium triplinerve Vahl showed antimelanogenesis activity in a melanin biosynthesis assay. By activity-guided fractionation, 7-methoxycoumarin (1) was isolated as an active compound. The IC50 of 1 on mushroom tyrosinase was 2360 μM (L-tyrosine was used as the substrate) and above 2840 μM (L-DOPA was used as the substrate), respectively. Regarding melanin formation inhibition in B16 melanoma cells, the IC50 of 1 was 1780 μM with 83% cell viability at IC50. Based on these results, we validated that the leaf extract is in line with the traditional use of the Dayak tribe in East Kalimantan. Copyright © 2012. Published by Elsevier B.V.

  19. Influence of five home whitening gels and a remineralizing gel on the enamel and dentin ultrastructure and hardness.

    PubMed

    Pinheiro, Helena Burlamaqui; Cardoso, Paulo Eduardo Capel

    2011-06-01

    To investigate the influence of calcium phosphate enhanced home whitening agents on human enamel and dentin surface microhardness and ultramorphology. Five intact molars crowns were used for ultrastructural analysis and five for microhardness test. Each resulting coronal structure was cut in slices. After measuring baseline Knoop Hardness Number (KHN) of the enamel and dentin, the slices were divided into six experimental groups and one control (n= 5). G1= 15% carbamide peroxide (CP); G2= 16% CP; G3= Ca and PO4 (remineralizing agent); G4= 16% CP with Ca and PO4; G5= 7.5% hydrogen peroxide (HP) with Ca and PO4; G6=7.5% HP with Ca. After each daily session of treatment, specimens were stored in distilled water (37 degrees C) until the next session. Products were applied for 2 weeks, according to manufacturers' instructions. Additional KHN weredetermined. Conventional whitening agents (G1; G2) and the gel with Ca (G6), caused KHN decrease (P< 0.05).The remineralizing and whitening agents with Ca and PO4 (G3; G4; G5) did not change KHN. A change of morphology was observed on enamel and dentin surfaces in G1; G2; G5.

  20. Clinical evaluation of a new 10% carbamide peroxide tooth-whitening agent.

    PubMed

    Barnes, D M; Kihn, P W; Romberg, E; George, D; DePaola, L; Medina, E

    1998-10-01

    NUPRO Gold Tooth Whitening System was evaluated for efficacy according to the proposed ADA guidelines for acceptance. Sixty participants with discolored anterior teeth participated in a 14-day, double-blind, clinical trial. The participants were matched for age, gender, and oral health status and were given either a placebo gel without the active agent or the NUPRO Gold active gel, which they wore in a custom-fabricated mouth guard for home use. The shade of each participant's maxillary anterior teeth was evaluated using a value-oriented Vita Lumin Vacuum Shade Guide before the study. The same shade guide was used to determine shade changes. Time of use of the agent and potential side effects, such as tooth and gingival hypersensitivity and tissue irritation, were assessed at all recall examinations and were recorded by participants in daily diaries. The average shade change for the placebo users was less than one shade. The average shade change for the NUPRO Gold users was 6.96 shades. Tooth hypersensitivity varied from none to severe. Tissue irritation was minimal. The results of these evaluations indicate that NUPRO Gold is effective as a tooth-whitening system, when administered properly under the supervision of a dentist, with commonly reported side effects of transient tooth sensitivity and minimal gingival sensitivity. Little or no change in tissue health was noted. This study was supported by Dentsply Preventive Care (York, Pennsylvania).

  1. The depigmenting effect of natural resorcinol type polyphenols Kuwanon O and Sanggenon T from the roots of morus australis.

    PubMed

    Hu, Shuting; Zheng, Zongping; Chen, Feng; Wang, Mingfu

    2017-01-04

    Morus australis, one of the major Morus species growing in East Asia, is rich in phenolic compounds. The extract of M. australis has been used as skin whitening components for a long period. The action mechanisms of its principal constituents are still unclear. This study aims to evaluate the skin lightening effects of phenolic compounds extracted from the root of M. australis in different melanocyte systems and artificial skin models. The depigmenting effect of resorcinol type polyphenols (RTPs) from the root extract of M. australis was evaluated in murine b16 and melan-a cell lines using a combined sulforhodamine B assay. Tyrosinase activity and the expression of melanogenesis proteins were evaluated for the mechanism study. The artificial skin model is used as a replacement of the animal test. Only Kuwanon O and Sanggenon T were found to have significant depigmenting effects in both murine b16 and melan-a cell lines. Their depigmenting mechanisms are slightly different in the two cell systems. In b16 cells, Kuwanon O and Sanggenon T, together with the other two RTPs, induced post-transcriptional degradations of MITF without suppressing its mRNA expression, leading to significant decreases of TRP-1 and TRP-2 production. While in melan-a cells, the levels of tyrosinase families were suppressed via MITF downregulation at both transcription and translation level by RTPs, with Kuwanon O inducing the greatest suppression. Further evaluations in artificial skin model demonstrated the outstanding depigmenting effects of Kuwanon O and Sanggenon T. Kuwanon O and Sanggenon T from M.australis root extract are two potential skin whitening ingredients. To screen resorcinol flavonone derivatives with an isoprenyl group in the Diels-Alder substituent might be an option for the search of potent hypopigmenting agents from plants. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  2. Skin Ageing: Natural Weapons and Strategies

    PubMed Central

    Binic, Ivana; Lazarevic, Viktor; Ljubenovic, Milanka; Mojsa, Jelena; Sokolovic, Dusan

    2013-01-01

    The fact that the skin is the most visible organ makes us aware of the ageing process every minute. The use of plant extracts and herbs has its origins in ancient times. Chronological and photo-ageing can be easily distinguished clinically, but they share important molecular features. We tried to gather the most interesting evidence based on facts about plants and plant extracts used in antiaging products. Our main idea was to emphasize action mechanisms of these plant/herbal products, that is, their “strategies” in fighting skin ageing. Some of the plant extracts have the ability to scavenge free radicals, to protect the skin matrix through the inhibition of enzymatic degradation, or to promote collagen synthesis in the skin. There are some plants that can affect skin elasticity and tightness. Certainly, there is a place for herbal principles in antiaging cosmetics. On the other hand, there is a constant need for more evaluation and more clinical studies in vivo with emphasis on the ingredient concentration of the plant/herbal products, its formulation, safety, and duration of the antiaging effect. PMID:23431351

  3. Effects of whitening dentifrice on yttria-stabilized tetragonal zirconia polycrystal surfaces after simulating brushing.

    PubMed

    Pinelli, Lígia Antunes Pereira; Gimenes Olbera, Amanda Caroline; Candido, Lucas Miguel; Miotto, Larissa Natiele; Antonio, Selma Gutierrez; Fais, Laiza Maria Grassi

    2017-01-01

    The changes that occur after brushing yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) are unknown. These changes may favor the retention of microorganisms and chemisorption of water, impairing its longevity. The purpose of this in vitro study was to evaluate the effects of a whitening dentifrice on Y-TZP surfaces after simulating 10 years of brushing. Seventy-two bar-shaped specimens (20×4×1.2 mm) were divided into 4 groups: storage in distilled water (SW, control), brushing with distilled water (BW), brushing with dentifrice (BD), and brushing with whitening dentifrice (BWD). Brushing was conducted using a linear brushing machine (878400 cycles, 0.98 N, soft toothbrush). The mean roughness (Ra) was analyzed with a profilometer and the superficial topography with scanning electron microscopy (SEM) at baseline and after treatment. Crystalline phases were characterized using x-ray diffraction. Baseline and posttreatment Ra were analyzed using the 1-way ANOVA and Tukey HSD multiple comparison test; the paired t test was used for intragroup comparison (all α=.05). The Ra (μm) means (before/after treatment) were SW 0.28/0.28; BW 0.32/0.31; BD 0.28/0.36; BWD 0.30/0.20. No statistically significant difference was found for Ra at baseline (P=.108) than for posttreatment results (P<.001); the BD group had higher Ra values when compared with baseline (P=.019); the BWD group had the lowest values (P<.001). The BD surfaces showed pronounced scratches and detachment of the surface, while BWD showed smoother surfaces; similar crystallographic results among groups were observed. Brushing Y-TZP with conventional dentifrice increased roughness, while brushing with whitening dentifrice reduced roughness. Neither dentifrice changed the crystallographic phases after brushing. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  4. A Randomized Controlled Clinical Trial to Evaluate Extrinsic Stain Removal of a Whitening Dentifrice.

    PubMed

    Terézhalmy, Géza; He, Tao; Anastasia, Mary Kay; Eusebio, Rachelle

    2016-12-01

    To evaluate the extrinsic stain removal efficacy of a new whitening dentifrice containing sodium hexametaphosphate (SHMP) over a two-week period. This study used a controlled and randomized, examiner-blind, single-center, two-treatment, parallel group design. Subjects with visible extrinsic dental stain on facial surfaces of their anterior teeth, and meeting all study criteria, were entered into the trial. The test group received the whitening dentifrice with sodium fluoride and SHMP and an ADA reference soft manual toothbrush. Subjects in the control group received a dental prophylaxis after the initial examination at Baseline and were instructed to use their usual oral hygiene products at home. Subjects returned at Day 3 and Week 2 for re-evaluation of extrinsic dental stain. Extrinsic stain was measured using the Interproximal Modified Lobene (IML) Stain Index; safety was assessed based on clinical examination. Fifty subjects (mean age 32.0 years) completed the study, with 25 in each group. Statistically significant reductions in composite stain for whole tooth, as well as interproximal, gingival, and body surfaces were observed for both groups at Day 3 and Week 2 (p < 0.0001) with no significant differences between the two groups (p > 0.3). At Day 3, median percent reductions in composite IML stain from Baseline were 98% for the prophylaxis group and 100% for the test dentifrice group. At Week 2, median percent reductions in composite IML stain were 100% compared to Baseline for both groups. No adverse events were reported for either group. The whitening dentifrice demonstrated a statistically significant reduction in IML stain after three days and two weeks of use relative to baseline. Stain reduction with the toothpaste was comparable to a dental prophylaxis.

  5. Analysis of the Chemical Modification of Dental Enamel Submitted to 35% Hydrogen Peroxide “In-Office” Whitening, with or without Calcium

    PubMed Central

    Santos, Fábio Pinheiro; Santos, Estevão Antero; dos Santos, Ramon Silva; dos Anjos, Marcelino José; de Miranda, Mauro Sayão

    2017-01-01

    Purpose The purpose of this study was to evaluate changes in calcium and phosphorus content in dental enamel when subjected to “in-office” whitening for an extended time by using a 35% hydrogen peroxide solution, with and without calcium. Materials and Methods 10 human teeth, from which the roots had been removed, were embedded in epoxy resin, and their surfaces were smoothed. The specimens were divided into two groups; in group 1, a whitening solution without calcium was used, while in group 2, the solution included calcium. Each specimen was evaluated at 6 different points before the bleaching treatment, and these points were reassessed after each session. A total of five sessions were carried out. Concentrations of calcium and phosphorus were measured by using the technique of X-ray fluorescence. Results After performing a statistical analysis, it was found that there was no statistically significant loss of calcium and phosphorus during the whitening treatment, and the groups showed no statistical differences. Conclusion Excessive use of hydrogen peroxide, with or without calcium, causes no loss of calcium and phosphorus. PMID:28932242

  6. Comparison of effectiveness of abrasive and enzymatic action of whitening toothpastes in removal of extrinsic stains - a clinical trial.

    PubMed

    Patil, P A; Ankola, A V; Hebbal, M I; Patil, A C

    2015-02-01

    To compare the effectiveness of abrasive component (perlite/calcium carbonate) and enzymatic component (papain and bromelain) of whitening toothpaste in removal of extrinsic stains. This study is a randomized, triple blind and parallel group study in which 90 subjects aged 18-40 years were included. At baseline, stains scores were assessed by Macpherson's modification of Lobene Stain Index and subjects were randomly assigned to two groups with 45 subjects in each. Group 1 used whitening toothpaste with enzymatic action and group 2 with abrasive action. After 1 month, stain scores were assessed for the effectiveness of the two toothpastes and 2 months later to check the stain prevention efficacy. Wilcoxson's test was used to compare between baseline 1 and 2 months stain scores, and Mann-Witney U-test was applied for intragroup comparison. The mean baseline total stain score for the subjects allocated to the enzymatic toothpaste was 37.24 ± 2.11 which reduced to 30.77 ± 2.48 in 1 month, and for the abrasive paste, total stain reduced from 35.08 ± 2.96 to 32.89 ± 1.95. The reductions in total stain scores with both the pastes were significant compared with baseline stain scores (at 1 month Group 1, P = 0.0233 and Group 2, P = 0.0324; at 2 months, Group 1 P = 0.0356). Both the toothpastes proved to be equally good in removal of extrinsic stains; however, the enzymatic paste showed better results as compared to abrasive toothpaste. Whitening toothpaste with abrasive action and enzymatic action are equally effective in removal of extrinsic stains; however, whitening toothpaste with abrasive action needs to be used with caution. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Graph-based normalization and whitening for non-linear data analysis.

    PubMed

    Aaron, Catherine

    2006-01-01

    In this paper we construct a graph-based normalization algorithm for non-linear data analysis. The principle of this algorithm is to get a spherical average neighborhood with unit radius. First we present a class of global dispersion measures used for "global normalization"; we then adapt these measures using a weighted graph to build a local normalization called "graph-based" normalization. Then we give details of the graph-based normalization algorithm and illustrate some results. In the second part we present a graph-based whitening algorithm built by analogy between the "global" and the "local" problem.

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

    PubMed

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

    2017-02-01

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

  9. Effects of Bleaching Agents Combined with Regular and Whitening Toothpastes on Surface Roughness and Mineral Content of Enamel.

    PubMed

    Attia, Mariana Lerner; Cavalli, Vanessa; do Espírito Santo, Ana Maria; Martin, Airton Abrahão; D'Arce, Maria Beatriz Freitas; Aguiar, Flávio Henrique Baggio; Lovadino, José Roberto; do Rego, Marcos Augusto; Cavalcanti, Andréa Nóbrega; Liporoni, Priscila Christiane Suzy

    2015-07-01

    The purpose of this study was to evaluate surface roughness and changes in the composition of enamel submitted to different bleaching protocols and toothbrushing with regular and whitening toothpastes. Bleaching treatment could promote morphological and chemical changes in enamel surface. Enamel blocks were randomized into nine groups (n=10) according to the bleaching treatment (no bleaching, control group; 6% hydrogen peroxide, HP; or 10% carbamide peroxide, CP) and toothpaste used (placebo, PL; regular, R; or whitening dentifrice, W). Bleaching was performed according to manufacturers' instructions and all groups were submitted to 30,000 cycles of simulated toothbrushing with toothpaste (PL, R, or W). Mineral content evaluation and enamel roughness were evaluated initially (T1), after bleaching (T2), and after toothbrushing (T3), using an energy-dispersive micro X-ray fluorescence spectrometer and profilometry, respectively. Data were statistically analyzed with two way ANOVA, Tukey, and Dunnett tests (5%). Enamel surface roughness was influenced by bleaching and toothbrushing. Surface roughness increased for the groups that brushed with the placebo dentifrice (CP+PL, HP+PL, C+PL) and for the control group that brushed with whitening dentifrice (C+W). Enamel Ca/P ratio decreased after bleaching, but toothbrushing, regardless of the dentifrice used, did not reduce the enamel mineral content. The bleaching treatment resulted in a decrease of enamel mineral content, but the studied dentifrices did not contribute to surface mineral loss.

  10. [Determination of fluorescent whitening agents in plastic food contact materials by high performance liquid chromatography with fluorescence detector].

    PubMed

    Jiao, Yanna; Ding, Li; Zhu, Shaohua; Fu, Shanliang; Gong, Qiang; Li, Hui; Wang, Libing

    2013-01-01

    A method for the determination of fluorescent whitening agents in plastic food contact materials by high performance liquid chromatography (HPLC) with fluorescence detector was developed. The samples were extracted with trichloromethane by sonication for 30 min at 40 degrees C. The HPLC method was performed on a column of Eclipse XDB-C18 (250 mm x 4.6 mm, 5 microm) by gradient elution using 5 mmol/L ammonium acetate and acetonitrile as the mobile phases, and detected by the fluorescence detector at an excitation wavelength of 350 nm and an emission wavelength of 430 nm. The experimental results indicated that the four fluorescent whitening agents were separated well. The limits of detection (LOD) (S/N = 3) were 0.3, 0.1, 0.05, 0.14 mg/L, and the limits of quantification (LOQ) (S/N = 10) were 1.0, 0.4, 0.2, 0.5 mg/L for 1,4-bis (4-cyanostyryl) benzene (C. I. 199), 1,4-bis (2-benzoxazolyl) naphthalene (C. I. 367), 4,4'-bis(2-methoxystyryl) biphenyl (C. I. 378) and 2,5-thiophenediylbis (5-tert-butyl-1,3-benzoxazole) (C. I. 184), respectively. Good linearities with correlation coefficients (r2) not less than 0.991 were obtained. The proposed method is simple, accurate, sensitive and can meet the requirements of the routine determination of fluorescent whitening agents in entry-exit products.

  11. Norartocarpetin from a folk medicine Artocarpus communis plays a melanogenesis inhibitor without cytotoxicity in B16F10 cell and skin irritation in mice

    PubMed Central

    2013-01-01

    Background Many natural products used in preventive medicine have also been developed as cosmeceutical ingredients in skin care products, such as Scutellaria baicalensis and Gardenia jasminoides. Norartocarpetin is one of the antioxidant and antityrosinase activity compound in Artocarpus communis; however, the cytotoxicity, skin irritation and antimelanogenesis mechanisms of norartocarpetin have not been investigated yet. Methods In the present study, cell viability in vitro and skin irritation in vivo are used to determine the safety of norartocarpetin. The melanogenesis inhibition of norartocarpetin was determined by cellular melanin content and tyrosinase in B16F10 melanoma cell. Moreover, we examined the related-melanogenesis protein by western blot analysis for elucidating the antimelanogenesis mechanism of norartocarpin. Results The result of the present study demonstrated that norartocarpetin not only present non-cytotoxic in B16F10 and human fibroblast cells but also non-skin irritation in mice. Moreover, our result also first found that norartocarpetin downregulated phospho-cAMP response element-binding (phospho-CREB) and microphthalmia-associated transcription factor (MITF) expression, which in turn decreased both synthesis of tyrosinases (TRP-1 and TRP-2) and cellular melanin content. This process is dependent on norartocarpetin phosphorylation by mitogen-activated protein kinases such as phospho-JNK and phospho-p38, and it results in decreased melanogenesis. Conclusion The present study suggests that norartocarpetin could be used as a whitening agent in medicine and/or cosmetic industry and need further clinical study. PMID:24325567

  12. Ionic liquid as a mobile phase additive in high-performance liquid chromatography for the simultaneous determination of eleven fluorescent whitening agents in paper materials.

    PubMed

    Wang, Qing; Chen, Xianbo; Qiu, Bin; Zhou, Liang; Zhang, Hui; Xie, Juan; Luo, Yan; Wang, Bin

    2016-04-01

    In the present study, 11 4,4'-diaminostilbene-2,2'-disulfonic acid based fluorescent whitening agents with different numbers of sulfonic acid groups were separated by using an ionic liquid as a mobile phase additive in high-performance liquid chromatography with fluorescence detection. The effects of ionic liquid concentration, pH of mobile phase B, and composition of mobile phase A on the separation of fluorescent whitening agents were systematically investigated. The ionic liquid tetrabutylammonium tetrafluoroborate is superior to tetrabutylammomnium bromide for the separation of the fluorescent whitening agents. The optimal separation conditions were an ionic liquid concentration at 8 mM and the pH of mobile phase B at 8.5 with methanol as mobile phase A. The established method exhibited low limits of detection (0.04-0.07 ng/mL) and wide linearity ranges (0.30-20 ng/mL) with high linear correlation coefficients from 0.9994 to 0.9998. The optimized procedure was applied to analyze target analytes in paper samples with satisfactory results. Eleven target analytes were quantified, and the recoveries of spiked paper samples were in the range of 85-105% with the relative standard deviations from 2.1 to 5.1%. The obtained results indicated that the method was efficient for detection of 11 fluorescent whitening agents. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Molecularly imprinted covalent organic polymers for the selective extraction of benzoxazole fluorescent whitening agents from food samples.

    PubMed

    Ding, Hui; Wang, Rongyu; Wang, Xiao; Ji, Wenhua

    2018-06-21

    Molecularly imprinted covalent organic polymers were constructed by an imine-linking reaction between 1,3,5-triformylphloroglucinol and 2,6-diaminopyridine and used for the selective solid-phase extraction of benzoxazole fluorescent whitening agents from food samples. Binding experiments showed that imprinting sites on molecularly imprinted polymers had higher selectivity for targets compared with those of the corresponding non-imprinted polymers. Parameters affecting the solid-phase extraction procedure were examined. Under optimal conditions, actual samples were treated and the eluent was analyzed with high-performance liquid chromatography with diode-array detection. The results showed that the established method owned the wide linearity, satisfactory detection limits and quantification limits, and acceptable recoveries. Thus, this developed method possesses the practical potential to the selectively determine benzoxazole fluorescent whitening agents in complex food samples. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  14. Study of the temporal evolution of Whitening Teeth immersed in Peroxide of hydrogen (H2O2) Using Digital Image Processing

    NASA Astrophysics Data System (ADS)

    Díaz, L.; Morales, Y.; Torres, C.

    2015-01-01

    The esthetic dentistry reference in our society is determined by several factors, including one that produces more dissatisfaction is abnormal tooth color or that does not meet the patient's expectations. For this reason it has been designed and implemented an algorithm in MATLAB that captures, digitizes, pre-processing and analyzed dental imaging by allowing to evaluate the degree of bleaching caused by the use of peroxide of hidrogen. The samples analyzed were human teeth extracted, which were subjected to different concentrations of peroxide of hidrogen and see if they can teeth whitening when using these products, was used different concentrations and intervals of time to analysis or study of the whitening of the teeth with the hydrogen peroxide.

  15. 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

  16. Raman spectroscopy analysis of dental enamel treated with whitening product - Influence of saliva in the remineralization.

    PubMed

    Silveira, J; Coutinho, S; Marques, D; Castro, J; Mata, A; Carvalho, M L; Pessanha, S

    2018-06-05

    In this work we present the analysis of dental enamel treated with an over-the-counter whitening product, bought in e-commerce at a very low cost, used without medical supervision in an abusive manner, in order to evaluate its demineralization action. Moreover, we studied the influence of renewal or non-renewal of saliva solution in which the specimens were stored throughout the study. The Degree of Demineralization was determined through the evaluation of the PO 4 3- symmetric stretching band (~959cm -1 ) in Raman spectra of the specimens in different days during the course of the study. Results showed that a maximum of demineralization occurred between days 27 and 34 of application. Titration of the whitening product revealed a content of hydrogen peroxide 170-fold higher than what is allowed in Europe, according with legislation. Despite this extreme concentration of hydrogen peroxide, the demineralization was not as great as could be expected suggesting an important role of the pH of the solution in this demineralization mechanism. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Raman spectroscopy analysis of dental enamel treated with whitening product - Influence of saliva in the remineralization

    NASA Astrophysics Data System (ADS)

    Silveira, J.; Coutinho, S.; Marques, D.; Castro, J.; Mata, A.; Carvalho, M. L.; Pessanha, S.

    2018-06-01

    In this work we present the analysis of dental enamel treated with an over-the-counter whitening product, bought in e-commerce at a very low cost, used without medical supervision in an abusive manner, in order to evaluate its demineralization action. Moreover, we studied the influence of renewal or non-renewal of saliva solution in which the specimens were stored throughout the study. The Degree of Demineralization was determined through the evaluation of the PO43- symmetric stretching band ( 959 cm-1) in Raman spectra of the specimens in different days during the course of the study. Results showed that a maximum of demineralization occurred between days 27 and 34 of application. Titration of the whitening product revealed a content of hydrogen peroxide 170-fold higher than what is allowed in Europe, according with legislation. Despite this extreme concentration of hydrogen peroxide, the demineralization was not as great as could be expected suggesting an important role of the pH of the solution in this demineralization mechanism.

  18. The globalization of whitening: prevalence of skin lighteners (or bleachers) use and its social correlates among university students in 26 countries.

    PubMed

    Peltzer, Karl; Pengpid, Supa; James, Caryl

    2016-02-01

    The aim of this study was to investigate the use of skin lighteners and its social correlates in university students from 26 low, middle income, and emerging economy countries. Using anonymous questionnaires, data were collected from 19,624 undergraduate university students (mean age 20.8, SD 2.8) from 27 universities in 26 countries across Asia, Africa, and the Americas. Multivariate logistic regression analysis was used to identify associations between sociodemographic, social, health risk, mental health and abuse, and the use of skin lighteners. Overall, the prevalence of previous 12-month skin lightener use was 24.5, and 16.7% in male and 30.0% in female students. The use of skin lighteners varied by country, ranging from 0% in Turkey to 83.8% in Thailand. In multivariate logistic regression analysis among both men and women, social variables (highly-organized religious activity and lack of personal mastery) and health variables (inconsistent condom use) were associated with skin lightening use. In addition, male students from a lower income country, having a lack of social support, and a history of childhood sexual abuse were more likely to use skin lighteners, and women aged 20-21 years old, residing on the university campus, being a student of health and welfare, and having a lack of personal control, inadequate physical activity, and depressive symptoms were more likely users of skin-lightening products. A high prevalence of skin lightener use was found in this large sample of university students, and social and health-related risk factors were identified. © 2015 The International Society of Dermatology.

  19. Effect of various tooth-whitening products on enamel microhardness.

    PubMed

    Grobler, S R; Majeed, A; Moola, M H

    2009-11-01

    The purpose of this in vitro study was to evaluate the effect of various tooth-whitening products containing carbamide peroxide (CP) or hydrogen peroxide (HP), on enamel microhardness. Enamel blocks were exposed to: Nite White ACP 10% CP (Group 2, n=10); Yotuel Patient 10% CP (Group 3, n=10); Opalescence PF 10% CP (Group 4, n=10); Opalescence PF 20% CP (Group 5, n=10); Opalescence Treswhite Supreme 10% HP (Group 6, n=10); Yotuel 10 Minutes 30% CP (Group 7, n=10); Opalescence Quick 45% CP (Group 8, n=10), Yotuel Special 35% HP (Group 9, n=10), Opalescence Boost 38% HP (Group 10, n=10) according to the instructions of the manufacturers. The control (Group 1, n=10) was enamel blocks kept in artificial saliva at 37 degrees C without any treatment. The microhardness values were obtained before exposure and after a 14-day treatment period. Specimens were kept in artificial saliva at 37 degrees C between treatments. Data were analysed using Kruskal-Wallis one-way ANOVA and Tukey-Kramer Multiple Comparison Test. Indent marks on the enamel blocks were also examined under the Scanning Electron Microscope. All whitening products decreased enamel microhardness except group 10 but only Groups 2, 3, 4, 5 and 7 showed significant decrease in enamel microhardness as compared to the control group (p < 0.05). Groups 2, 3 and 7 differed significantly from all the other groups (p < 0.05). The highest damage was recorded for Group 2 (Nite White ACP 10% CP), which differed significantly from Groups 3 and 7. SEM images also showed damage to enamel. All products tested in this study decreased enamel microhardness except Opalescence Boost 38% HP. The products containing carbamide peroxide were more damaging to enamel because of the longer application times. Nite White ACP 10% CP showed the highest reduction in enamel microhardness as compared to other products tested.

  20. [Effects of tooth whitening agents and acidic drinks on the surface properties of dental enamel].

    PubMed

    Chen, Xiaoling; Chen, Zhiqun; Lin, Yao; Shao, Jinquan; Yin, Lu

    2013-10-01

    Using tooth whitening agents (bleaching clip) in vitro and acidic drinks, we conducted a comparative study of the changes in enamel surface morphology, Ca/P content, and hardness. Tooth whitening glue pieces, cola, and orange juice were used to soak teeth in artificial saliva in vitro. Physiological saline was used as a control treatment. The morphology of the four groups was observed under a scanning electron microscope (SEM) immediately after the teeth were soaked for 7 and 14 d. The changes in Ca/P content and microhardness were analyzed. The enamel surfaces of the teeth in the three test groups were demineralized. The Ca/P ratio and the average microhardness were significantly lower than those of the control group immediately after the teeth were soaked (P < 0.05). The Ca/P ratio and microhardness gradually increased after 7 d. No significant difference was observed between the control group and the test groups after 14 d (P > 0.05). Bleaching agents caused transient demineralization of human enamel, but these agents could induce re-mineralization and repair of enamel over time. Demineralization caused by bleaching covered a relatively normal range compared with acidic drinks and daily drinking.

  1. Connectedness to nature and public (skin) health perspectives: results of a representative, population-based survey among Austrian residents.

    PubMed

    Haluza, Daniela; Simic, Stana; Höltge, Jan; Cervinka, Renate; Moshammer, Hanns

    2014-01-20

    Connectedness to nature (CN) influences motivation to have contact with outdoor natural environments. Spending leisure time in natural environments is beneficial for human health and well-being. Besides these positive effects, health risks of open-air activities are mainly related to unprotected sun light exposure-associated acute and chronic skin hazards. Thus, we conducted a cross-sectional, representative telephone survey among Austrian residents to study the association of perceived CN level with sun-exposure knowledge, tanning habits, and sun protective behaviour. In total, 1,500 study subjects (50.5% females) participated in this questionnaire survey. Although knowledge about tanning and motives to tan were similar among genders, females performed more photoprotective measures and were more connected to nature (all p < 0.001) compared to males. Older age and outdoor sport were significant gender-independent predictor variables influencing perceived CN level. Additionally, level of education was relevant in male CN, whereas non-smoking and higher knowledge were predictive of female CN. This survey provides so far unreported empirical data on the relationship between nature connectedness and skin health-relevant recreational habits of Austrian residents. The findings suggest to integrate hitherto neglected gender-specific Public (Skin) Health promotion when counselling on the manifold health advantages of outdoor activities.

  2. Connectedness to Nature and Public (Skin) Health Perspectives: Results of a Representative, Population-Based Survey among Austrian Residents

    PubMed Central

    Haluza, Daniela; Simic, Stana; Höltge, Jan; Cervinka, Renate; Moshammer, Hanns

    2014-01-01

    Connectedness to nature (CN) influences motivation to have contact with outdoor natural environments. Spending leisure time in natural environments is beneficial for human health and well-being. Besides these positive effects, health risks of open-air activities are mainly related to unprotected sun light exposure-associated acute and chronic skin hazards. Thus, we conducted a cross-sectional, representative telephone survey among Austrian residents to study the association of perceived CN level with sun-exposure knowledge, tanning habits, and sun protective behaviour. In total, 1,500 study subjects (50.5% females) participated in this questionnaire survey. Although knowledge about tanning and motives to tan were similar among genders, females performed more photoprotective measures and were more connected to nature (all p < 0.001) compared to males. Older age and outdoor sport were significant gender-independent predictor variables influencing perceived CN level. Additionally, level of education was relevant in male CN, whereas non-smoking and higher knowledge were predictive of female CN. This survey provides so far unreported empirical data on the relationship between nature connectedness and skin health-relevant recreational habits of Austrian residents. The findings suggest to integrate hitherto neglected gender-specific Public (Skin) Health promotion when counselling on the manifold health advantages of outdoor activities. PMID:24448634

  3. Phenolic profiles and antioxidant activity of Turkish Tombul hazelnut samples (natural, roasted, and roasted hazelnut skin).

    PubMed

    Pelvan, Ebru; Olgun, Elmas Öktem; Karadağ, Ayşe; Alasalvar, Cesarettin

    2018-04-01

    The phenolic profiles and antioxidant status of hazelnut samples [natural (raw) hazelnut, roasted hazelnut, and roasted hazelnut skin] were compared. Free and bound (ester-linked and glycoside-linked) phenolic acids were examined using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Comprehensive identification of phenolics was carried out using Q-exactive hybrid quadrupole-orbitrap mass spectrometer (Q-OT-MS). Samples were also assessed for their total phenolics and antioxidant activities using three different assays. Ten free and bound phenolic acids were quantified in hazelnut samples. Roasted hazelnut skin contained the highest content of total phenolic acids, followed by natural and roasted hazelnuts. The majority of phenolic acids were present in the bound form. Using a Q-OT-MS, 22 compounds were tentatively identified, 16 of which were identified for the first time in hazelnut samples. The newly identified compounds consisted of flavonoids, phenolic acids and related compounds, hydrolysable tannins and related compounds, and other phenolics. Three antioxidant assays demonstrated similar trends that roasted hazelnut skin rendered the highest activity. The present work suggests that roasted hazelnut skin is a rich source of phenolics and can be considered as a value-added co-product for use as functional food ingredient and antioxidant. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Relationship between natural tooth shade and skin colour.

    PubMed

    Nourbakhsh, M; Mousavinejad, N; Adli, A R; Harati, M

    2013-06-01

    The purpose of this study was to assess the correlation of skin colour and tooth shade. One hundred and twenty six individuals aging between 18 to 25 years participated in this study. Colour of the maxillary central incisors was examined by VITA easy shade. Tooth shades were assigned to four ordinal values. Nivea Beauty Protect Foundation shade sample was used as a guide to assess facial skin colour Shin colours were also assigned to four ordinal values. Spearman test revealed that there was a significant relationship between tooth shade and skin colour Total co-relation factor was 51.6% (p <0 .01). Co-relation factors were 57% for women and 27% for men (p <0 .01). The highest tooth shade prevalence belonged to the second group and the highest skin colour prevalence was also in the second skin colour group.

  5. Low-temperature atmospheric pressure plasma enhanced tooth whitening: the next-generation technology.

    PubMed

    Claiborne, D; McCombs, G; Lemaster, M; Akman, M A; Laroussi, M

    2014-05-01

    To evaluate the safety and effectiveness of the plasma pencil (PP) device in conjunction with H2 O2 gel. The purpose of this study was to determine whether LTAPP delivered using the PP would enhance the tooth-whitening process while causing no thermal threat. The study consisted of thirty extracted human teeth that were randomized into two groups: Group I received LTAPP plus 36% H2 O2 gel at 10, 15 and 20 min and Group II received 36% H2 O2 gel only at the same time intervals. Tooth surface temperature was measured periodically throughout the experiment using a non-contact thermometer. Digital photographs were taken pre- and post-treatment and transferred to Adobe Photoshop for comparison, using the CIELAB Color Value System. Only L* (lightness) values were evaluated in this study. Data were analysed using descriptive statistics and t-test at the 0.05 level. The results revealed a statistically significant difference in mean CIE L* values after exposure to LTAPP plus 36% H2 O2 gel, compared with 36% H2 O2 only, in the 10- and 20-min groups (P = 0.0003 and 0.0103, respectively). The temperature in both treatment groups remained under 80°F throughout the study, which is below the thermal threat for vital tooth bleaching. Utilizing PP device in conjunction with 36% H2 O2 safely accelerates and enhances the tooth-whitening process. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. 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.

  7. Experimental studies on the nature of sensitive skin.

    PubMed

    Kligman, A M; Sadiq, Iqbal; Zhen, Yaxian; Crosby, Marilyn

    2006-11-01

    In the USA, Europe and Japan 40 to 50% of women report that they have sensitive skin, defined as abnormal sub-clinical sensory responses to drugs, cosmetics and toiletries in the absence of visible signs of irritation. Itching, burning, stinging and tightness are the commonest complaints, which mainly afflict women. Manufacturers of skin care products have made available a large variety of products which are designed for persons with sensitive skin. Such products are not required by regulatory agencies to submit evidence of safety and efficacy, allowing marketers to make claims that are often exaggerated, irrational and even preposterous. The consumer with self-assessed sensitive skin has no way of judging which products are likely to be most beneficial and least harmful. The marketplace is awash with products for which there is no evidence that the rosy claims have been substantiated by appropriate testing procedures. There is no internationally accepted consensus regarding the criteria which define sensitive skin. Many papers have been published in the last 15 years, mainly originating from industry, which express widely differing views regarding what constitutes sensitive skin. For some, any adverse reaction to a product topically applied to sensitive skin, including breakouts, redness, scaling etc., a panoply of adverse reactions which is virtually meaningless. Others include environmental factors as causative, including cold, dry wind, heat and high humidity, solar radiation, etc., which add to the manifest complexities of the subject. This is the first paper in a series which provides a comprehensive review of the subject, emphasizing the all too many controversies and confusions arising from the lack of a consensus regarding the identification, classification, epidemiology, prevalence and pathogenesis of sensitive skin. Sensitive skin is a biologic reality and not a psychological, fashionable fantasy on the part of impressionable women. There is an urgent

  8. Randomized clinical study of alterations in the color and surface roughness of dental enamel brushed with whitening toothpaste.

    PubMed

    de Moraes Rego Roselino, Lourenço; Tirapelli, Camila; de Carvalho Panzeri Pires-de-Souza, Fernanda

    2018-03-30

    This clinical study evaluated the influence of whitening toothpaste on color and surface roughness of dental enamel. Initially, the abrasiveness of the toothpastes used (Sorriso Dentes Brancos [SDB]; Colgate Luminous White and Close up White Now) was tested on 30 (n = 10) plexiglass acrylic plates that were submitted to mechanical tooth brushing totalizing 29,200 cycles. Subsequently, 30 participants were selected, and received a toothbrush and nonwhitening toothpaste (SDB). The participants used these products for 7 days and initial color readouts (Spectrophotometer) and surface roughness of one maxillary central incisors was performed after this period of time. For surface roughness readouts, one replica of the maxillary central incisor was obtained by a polyvinyl siloxane impression material (Express) and polyurethane resin. After baseline measurements, participants were separated into three groups (n = 10), according to the toothpaste used. The participants returned after 7, 30, and 90 days when new color readouts and surface roughness were recorded. The measured values were statistically analyzed (2-way-ANOVA, repeated measures, Tukey, P < .05). Whitening toothpastes did not promote significant (P > .05) color alteration and nor increased the surface roughness of the dental enamel in brushing time of the study. The abrasiveness of whitening toothpaste and the brushing trial period did not affect the surface roughness of dental enamel. However, color changes observed on enamel were above the perceptibility and acceptability thresholds reported in the literature. The over-the-counter toothpastes tested had an effect on dental enamel color above the perceptibility and acceptability thresholds but did not change the surface roughness of the teeth. © 2018 Wiley Periodicals, Inc.

  9. Natural killer T cell facilitated engraftment of rat skin but not islet xenografts in mice.

    PubMed

    Gordon, Ethel J; Kelkar, Vinaya

    2009-01-01

    We have studied cellular components required for xenograft survival mediated by anti-CD154 monoclonal antibody (mAb) and a transfusion of donor spleen cells and found that the elimination of CD4(+) but not CD8(+) cells significantly improves graft survival. A contribution of other cellular components, such as natural killer (NK) cells and natural killer T (NKT) cells, for costimulation blockade-induced xenograft survival has not been clearly defined. We therefore tested the hypothesis that NK or NKT cells would promote rat islet and skin xenograft acceptance in mice. Lewis rat islets or skin was transplanted into wild type B6 mice or into B6 mice that were Jalpha18(null), CD1(null), or beta2 microglobulin (beta2M)(null) NK 1.1 depleted, or perforin(null). Graft recipients were pretreated with an infusion of donor derived spleen cells and a brief course of anti-CD154 mAb treatments. Additional groups received mAb or cells only. We first observed that the depletion of NK1.1 cells does not significantly interfere with graft survival in C57BL/6 (B6) mice. We used NKT cell deficient B6 mice to test the hypothesis that NKT cells are involved in islet and skin xenograft survival in our model. These mice bear a null mutation in the gene for the Jalpha18 component of the T-cell receptor. The component is uniquely associated with NKT cells. We found no difference in islet xenograft survival between Jalpha18(null) and wild type B6 mice. In contrast, median skin graft survival appeared shorter in Jalpha18(null) recipients. These data imply a role for Jalpha18(+) NKT cells in skin xenograft survival in treated mice. In order to confirm this inference, we tested skin xenograft survival in B6 CD1(null) mice because NKT cells are CD1 restricted. Results of these trials demonstrate that the absence of CD1(+) cells adversely affects rat skin graft survival. An additional assay in beta2M(null) mice demonstrated a requirement for major histocompatibility complex (MHC) class I

  10. Masking of Enamel Fluorosis Discolorations and Tooth Misalignment With a Combination of At-Home Whitening, Resin Infiltration, and Direct Composite Restorations.

    PubMed

    Perdigão, J; Lam, V Q; Burseth, B G; Real, C

    This clinical report illustrates a conservative technique to mask enamel discolorations in maxillary anterior teeth caused by hypomineralization associated with enamel fluorosis and subsequent direct resin composite to improve the anterior esthetics. The treatment consisted of at-home whitening with 10% carbamide peroxide gel with potassium nitrate and sodium fluoride in a custom-fitted tray to mask the brown-stained areas, followed by resin infiltration to mask the white spot areas. An existing resin composite restoration in the maxillary right central incisor was subsequently replaced after completion of the whitening and resin infiltration procedures, whereas the two misaligned and rotated maxillary lateral incisors were built up with direct resin composite restorations to provide the illusion of adequate arch alignment, as the patient was unable to use orthodontic therapy.

  11. 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 ...

  12. Long-chain ionic liquid based mixed hemimicelles and magnetic dispersed solid-phase extraction for the extraction of fluorescent whitening agents in paper materials.

    PubMed

    Wang, Qing; Qiu, Bin; Chen, Xianbo; Wang, Bin; Zhang, Hui; Zhang, Xiaoyuan

    2017-06-01

    A novel mixed hemimicelles and magnetic dispersive solid-phase extraction method based on long-chain ionic liquids for the extraction of five fluorescent whitening agents was established. The factors influenced on extraction efficiency were investigated. Under the optimal conditions, namely, the pH of sample solution at 8.0, the concentration of long chain ionic liquid at 0.5 mmol/L, the amount of Fe 3 O 4 nanoparticle at 12 mg, extraction time at 10 min, pH 6.0 of methanol as eluent, and the desorption time at 1 min, satisfactory results were obtained. Wide linear ranges (0.02-10 ng/mL) and good linearity were attained (0.9997-0.9999). The intraday and interday RSDs were 2.1-8.3%. Limits of detection were 0.004-0.01 ng/mL, which were decreased by almost an order of magnitude compared to direct detection without extraction. The present method was applied to extract the fluorescent whitening agents in two kinds of paper samples, obtaining satisfactory results. All showed results illustrated that the detection sensitivity was improved and the proposed method was a good choice for the enriching and monitoring of trace fluorescent whitening agents. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. The abrasive effect of commercial whitening toothpastes on eroded enamel.

    PubMed

    Mosquim, Victor; Martines Souza, Beatriz; Foratori Junior, Gerson Aparecido; Wang, Linda; Magalhães, Ana Carolina

    2017-06-01

    To evaluate the in vitro abrasive effect of commercial whitening toothpastes on eroded bovine enamel samples in respect to erosive tooth wear. 72 bovine crowns were embedded, polished and subjected to the baseline profile analysis. The samples were then protected in 2/3 of the enamel surface and were randomly assigned to six groups (n= 12/group): G1: Oral-B 3D White, G2: Close-up Diamond Attraction Power White, G3: Sorriso Xtreme White 4D, G4: Colgate Luminous White, G5: Crest (conventional toothpaste), G6:erosion only (control). All samples were submitted to an erosive pH cycling (4 x 90 seconds in 0.1% citric acid, pH 2.5, per day) and abrasive challenges (2 x 15 seconds, per day) for 7 days. After the first and the last daily cycles, the samples were subjected to abrasive challenges, using a toothbrushing machine, soft toothbrushes and slurry of the tested toothpastes (1.5 N). Between the challenges, the samples were immersed in artificial saliva. The final profile was obtained and overlaid to the baseline profile for the calculation of the erosive tooth wear (μm). The data were subjected to Kruskal-Wallis/Dunn tests (P< 0.05). G1 promoted the highest enamel wear (3.68±1.06 μm), similarly to G3 (3.17± 0.80 μm) and G4 (3.44± 1.29 μm). G3 and G4 performed similarly between them and compared with G5 (2.35± 1.44 μm). G2 (1.51± 0.95 μm) and G6 (0.85± 0.36 μm) showed the lowest enamel wear, which did not differ between them and from G5. Oral-B 3D White showed the highest abrasive potential while Close-up Diamond Attraction Power White showed the lowest abrasive potential on eroded enamel in vitro. This study showed that some commercial whitening toothpastes, especially those containing pyrophosphate associated with hydrated silica, enhanced enamel erosive wear.

  14. Elastic MCF Rubber with Photovoltaics and Sensing on Hybrid Skin (H-Skin) for Artificial Skin by Utilizing Natural Rubber: Third Report on Electric Charge and Storage under Tension and Compression †.

    PubMed

    Shimada, Kunio

    2018-06-06

    In the series of studies on new types of elastic and compressible artificial skins with hybrid sensing functions, photovoltaics, and battery, we have proposed a hybrid skin (H-Skin) by utilizing an electrolytically polymerized magnetic compound fluid (MCF) made of natural rubber latex (NR-latex). By using the experimental results in the first and second reports, we have clarified the feasibility of electric charge at irradiation, and that without illumination under compression and elongation. The former was explained in a wet-type MCF rubber solar cell by developing a tunneling theory together with an equivalent electric circuit model. The latter corresponds to the battery rather than to the solar cell. As for the MCF rubber battery, depending on the selected agent type, we can make the MCF rubber have higher electricity and lighter weight. Therefore, the MCF rubber has an electric charge and storage whether at irradiation or not.

  15. Comparison of two low sensitivity whiteners.

    PubMed

    Callan, Richard S; Browning, William D; Downey, Mary C; Brackett, Martha G

    2008-02-01

    To evaluate two commercially available doctor-supplied, patient-applied, bleaching systems for their ability to whiten the maxillary anterior teeth while at the same time not causing sensitivity. 46 participants were randomly assigned to one of two groups: One group received Rembrandt Xtra-Comfort and the other group Nite White Excel 2Z. Bleaching stents were fabricated and the bleaching systems were used following manufacturers' instructions. Participants recorded tray use and any sensitivity on a daily basis. Participants bleached for 2 weeks followed by 2 weeks of no bleaching. Color was evaluated at the first, second and fourth week following the initial delivery of bleaching trays. Color change was measured using the Vita Classic Shade Guide arranged by value. As a group, participants in the NW2Z group bleached for 302 days with a total of 48 days (16%) of sensitivity recorded. The Rembrandt Xtra Comfort group bleached for 313 total days with 97 days (31%) of sensitivity recorded. The difference in sensitivity between the two products proved to be statistically significant (Chi-square analysis, P < or = 0.0001). The median shade change for both products following 2 weeks of active treatment was six tabs. At the 4-week evaluation, the median shade change was 5.5 and 6.0 tabs respectively for Rembrandt and Nite White. There was no statistical difference between the products in respect to shade change.

  16. The effects of natural S-equol supplementation on skin aging in postmenopausal women: a pilot randomized placebo-controlled trial.

    PubMed

    Oyama, Ayuko; Ueno, Tomomi; Uchiyama, Shigeto; Aihara, Tomohiko; Miyake, Akira; Kondo, Sumio; Matsunaga, Kayoko

    2012-02-01

    The aim of this study was to investigate the effects of the natural S-equol supplement on skin aging in equol-nonproducing Japanese postmenopausal women. A randomized, double-blind, placebo-controlled trial examined the use of the natural S-equol supplement for 12 weeks in 101 postmenopausal Japanese women who were equol nonproducers. They were randomly assigned to one of three groups: placebo (n = 34), 10 mg S-equol/day (EQL10; n = 34), or 30 mg S-equol/day (EQL30; n = 33). Skin parameters of crow's-feet wrinkles (area and depth), hydration, transepidermal water loss, and elasticity were measured at baseline and at monthly intervals during treatment. Vaginal cytology, endometrial thickness, and mammography were performed before and after treatment. Serum hormone concentrations were measured at the same time as skin parameters. The EQL10 and EQL30 groups showed significant reductions in wrinkle area compared with the placebo group (P < 0.05). There was a significant difference in wrinkle depth between the placebo group and the EQL30 group (P < 0.05). Other skin parameters did not show significant differences after the treatment in any group. There were no abnormal results in hormone status or gynecological examinations. Our data suggest that natural S-equol supplementation (EQL10 and EQL30) may have a beneficial effect on crow's-feet wrinkles in postmenopausal women without serious adverse events.

  17. Skin Conditions during Pregnancy

    MedlinePlus

    ... by an increase in the body’s melanin—a natural substance that gives color to the skin and hair. Dark spots and melasma usually fade on their ... of female reproductive organs. Immune System: The body’s natural defense ... pubic hair that darkens during pregnancy. Melasma: A common skin ...

  18. Facile synthesis of α-Fe{sub 2}O{sub 3}@ porous hollow yeast-based carbonaceous microspheres for fluorescent whitening agent-VBL wastewater treatment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zheng, Pei; Tong, Zhiqing; Bai, Bo, E-mail: baibochina@163.com

    Porous hollow carbonaceous microspheres (PHCMs) fabricated from yeast cells by hydrothermal treatment have stimulated interest because of their outstanding chemical and physical properties. Herein, the functionalizations of PHCMs by further coating of α-Fe{sub 2}O{sub 3} nanoparticles onto the surface were carried out. The structure of resulted α-Fe{sub 2}O{sub 3}@PHCMs products were characterized by field emission scanning electron microscopy (FE-SEM), energy dispersive spectrometry (EDS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and BET specific surface area measurements (BET), respectively. Its promising application was evaluated by the Fenton-like degradation of fluorescent whitening agent-VBL from aqueous solutions. - Graphical abstract: In thismore » work, novel α-Fe{sub 2}O{sub 3}@porous hollow carbonaceous microspheres (α-Fe{sub 2}O{sub 3}@PHCMs) were synthesized through a combination of hydrothermal method and calcinations route and achieved excellent removal efficiency for fluorescent whitening Agent-VBL. - Highlights: • The hybrid α-Fe{sub 2}O{sub 3}@ porous hollow microspheres (PHCMs) were firstly fabricated. • The formation mechanism of α-Fe{sub 2}O{sub 3}@PHCMs microspheres was proposed and verified. • Dithizone played a key role in the synthesis of α-Fe{sub 2}O{sub 3}@PHCMs composites. • A favorable removal for the fluorescent whitening agent-VBL were achieved.« less

  19. Morphological study on the pressure ulcer-like dermal lesions formed in the rat heel skin after transection of the sciatic nerves.

    PubMed

    Haba, Daijiro; Minami, Chie; Miyagawa, Miki; Arakawa, Takamitsu; Miki, Akinori

    2017-01-01

    Due to transection of bilateral sciatic nerves, pressure ulcer-like dermal lesion occurred in the hairy skin covering of the heel skin in almost all rats. In the present study, chronological changes of the rat heel skin after the transection were morphologically and immunohistochemically examined. In the heel skin, redness and swelling began by 3days after the operation, and open wound formed by 17days. At the redness and swelling stage, edema extensively occurred in the dermis. At the thickening stage, the epidermis at the pressed site became transiently thicker, and at the whitening stage, rapidly thinner. At these stages, the epidermis in the skin surrounding the pressed site became gradually thicker. At the yellow scar stage, the skin was covered only by necrotic tissues and horny layer. These layers were scratched during walking and turning, and the yellow scar stage became the open wound stage. Inflammatory reaction began at the thickening stage, and at the yellow scar and open wound stages, necrosis, infiltration of inflammatory cells and dilation of small blood vessels were observed. These morphological features are quite similar to those in the human pressure ulcer. These findings suggest that these dermal injuries could compare the human pressure ulcer for medical treatment and depressurization in future study. Copyright © 2016 Elsevier GmbH. All rights reserved.

  20. Delayed manifestation of bilateral scleral thinning after I-BRITE(®) procedure and review of literature for cosmetic eye-whitening procedures.

    PubMed

    Moshirfar, Majid; McCaughey, Michael V; Fenzl, Carlton R; Santiago-Caban, Luis; Kramer, Gregory D; Mamalis, Nick

    2015-01-01

    To report a case of delayed-onset bilateral scleral thinning and calcium deposition following a cosmetic ocular-whitening procedure (I-BRITE(®)). A 33-year-old male patient with a history of right-sided ptosis repair and left-sided anterior uveitis had previously undergone bilateral I-BRITE treatment for chronic conjunctival hyperemia. Four years after the procedure, the patient was referred to our institution with bilateral scleral thinning and overlying calcific depositions. A literature review was performed through PubMed from 1980 through 2014 using the search terms 'cosmetic', 'ocular', 'conjunctivectomy', 'regional conjunctivectomy', 'I-BRITE', 'eye-whitening', 'scleritis', 'necrotizing scleritis', 'anterior uveitis', 'mitomycin C', '5-fluorouracil', and 'bevacizumab', along with associated cross-referencing from relevant articles. Examination of the patient revealed bilateral necrotizing scleritis within the nasal region of both eyes. Calcified plaques were also present within the areas of scleromalacia, along with epithelial defects demonstrated with fluorescein staining. Although evidence of previous intraocular inflammation was apparent within the left eye, there were no active signs of inflammation evident within either eye on initial presentation. Complication rates reported in the literature include: scleral thinning (1.8%), calcific plaque formation (2.9%), fibrovascular proliferation (13%), diplopia (1.2%), elevation of intraocular pressure (4.2%), and recurrence of conjunctival hyperemia (2.1%). Cosmetic ocular whitening procedures have an attendant high complication rate, and have been associated with several adverse postoperative complications, which have in turn generated several reservations regarding the veritable benefit of the procedure. Many postsurgical complications may demonstrate delayed apparition, varying from several months to several years after primary surgical intervention as in the case reported here.

  1. Biology of Skin Color.

    ERIC Educational Resources Information Center

    Corcos, Alain

    1983-01-01

    Information from scientific journals on the biology of skin color is discussed. Major areas addressed include: (1) biology of melanin, melanocytes, and melanosomes; (2) melanosome and human diversity; (3) genetics of skin color; and (4) skin color, geography, and natural selection. (JN)

  2. Biotechnological production of arbutins (α- and β-arbutins), skin-lightening agents, and their derivatives.

    PubMed

    Seo, Dong-Ho; Jung, Jong-Hyun; Lee, Jae-Eun; Jeon, Eun-Jung; Kim, Wooki; Park, Cheon-Seok

    2012-09-01

    Arbutins (α- and β-arbutins) are glycosylated hydroquinones that are commercially used in the cosmetic industry. These compounds have an inhibitory function against tyrosinase, a critical enzyme for generating pigments, which leads to the prevention of melanin formation, resulting in a whitening effect on the skin. Although β-arbutin is found in various plants including bearberry, wheat, and pear, α-arbutin and other arbutin derivatives are synthesized by chemical and enzymatic methods. This article presents a mini-review of recent studies on the production of α-arbutin and other α- and β-arbutin derivatives via enzymatic bioconversion methods. In addition, the structures of α- and β-arbutin derivatives and their biological activities are discussed. The catalytic characteristics of various enzymes used in the biosynthesis of arbutin derivatives are also reviewed.

  3. Fabrication of Metal Nanoparticle-Modified Screen Printed Carbon Electrodes for the Evaluation of Hydrogen Peroxide Content in Teeth Whitening Strips

    ERIC Educational Resources Information Center

    Popa, Adriana; Abenojar, Eric C.; Vianna, Adam; Buenviaje, Czarina Y. A.; Yang, Jiahua; Pascual, Cherrie B.; Samia, Anna Cristina S.

    2015-01-01

    A laboratory experiment in which students synthesize Ag, Au, and Pt nanoparticles (NPs) and use them to modify screen printed carbon electrodes for the electroanalysis of the hydrogen peroxide content in commercially available teeth whitening strips is described. This experiment is designed for two 3-h laboratory periods and can be adapted for…

  4. Comparison of in vitro fluoride uptake from whitening toothpastes and a conventional toothpaste in demineralised enamel.

    PubMed

    Altenburger, Markus J; Bernhart, Jasmin; Schicha, Thurid D; Wrbas, Karl-Thomas; Hellwig, Elmar

    2010-01-01

    Studies on the compatibility of abrasives and fluoride compounds deal exclusively with fluoride uptake and remineralization after storing the enamel specimens in a toothpaste-saliva mixture. The influence of brushing on the fluoride uptake when highly abrasive toothpastes are used has hardly been investigated so far. The aim of the present study was to investigate fluoride uptake in initially demineralised dental enamel after storage in, or brushing with, whitening toothpaste slurries, compared to a conventional toothpaste. For this purpose two widely available whitening toothpastes with ionically bound fluoride (sodium fluoride NaF), two with covalently-bound fluoride toothpastes (sodium monofluorophosphate, NaMFP) and a conventional amine fluoride toothpaste (AmF) were compared. The fluoride uptake after use of the AmF toothpaste was shown to be statistically significantly higher than that after application of the NaF toothpastes, which in turn was statistically significantly higher than the uptake resulting from NaMFP application. The fluoride uptake was slightly higher when the enamel samples were brushed with NaF toothpaste, rather than just stored in the respective toothpaste slurry. Brushing with highly abrasive toothpastes did not negatively influence fluoride uptake in demineralised dental enamel. The ionic form of the fluoride in toothpastes appears to be critical for increased fluoride uptake. The acidic components of the AmF toothpaste improved fluoride uptake compared to alkaline NaF toothpastes.

  5. Application of proanthocyanidins from peanut skins as a natural yeast inhibitory agent.

    PubMed

    Sarnoski, Paul J; Boyer, Renee R; O'Keefe, Sean F

    2012-04-01

    Proanthocyanidins were extracted from peanut skins and investigated for their antimicrobial activity against Saccharomyces cerevisiae, Zygosaccharomyces bailii, and Zygosaccharomyces bisporus in traditional growth media (Sabouraud Dextrose and Maltose broth) and a simulated apple juice beverage. Peanut skins extracts (PSE) were prepared through a multisolvent extraction procedure. The PSE extended the lag phase growth of the 3 yeasts studied at a concentration of 1 mg/mL and at 10 mg/mL yeast growth was totally inhibited for 120 h. PSE was fractionated by normal phase high performance liquid chromatography and the active components/fractions were determined. Compounds present in the fractions were identified by liquid chromatography-mass spectrometry to determine the compounds responsible for inhibition. Fractions consisting mostly of A-type proanthocyanidin dimers, trimers, and tetramers showed the highest percent inhibition toward the yeasts tested in this study. Both optical density (OD) and standard enumeration plating methods were performed in this study. The OD method led to an overestimation of the inhibitory effects of PSE, the 2 methods agreed in respect to treatment effects but not the severity of the inhibition. There is a growing consumer demand for "fresh like" products containing reduced amounts of chemical preservatives without compromising food safety and quality. Therefore, the goal of this study was to determine if an extract of peanut skins containing flavonoid rich compounds could function as a natural antimicrobial in a model beverage system. Proteins were removed through the process of producing the peanut skin extract, thus it is unlikely to contain peanut allergens. The antimicrobial compounds mentioned in this study were successfully integrated into a model beverage system, and were found to have antimicrobial effect. However, the incorporation of these compounds would likely lead to negative sensory attributes at the concentration needed

  6. Poria cocos Wolf extracts represses pigmentation in vitro and in vivo.

    PubMed

    Lee, HyunKyung; Cha, Hwa Jun

    2018-04-30

    In skin, melanocytes determine skin color using melanogenesis, which induces protective mechanism to oxidative stress and UV damage. However, when melanin is excessive produced by the various stimulus, the accumulated melanin induces hyperpigmentation disease such as melasma, freckles, Melanism ware induced. Therefore, it is implicated to finding potential agents for whitening to be used in cosmetic products. In our present study, we show that Poria cocos Wolf extracts decreased melanin synthesis in B16F10. And then this inhibition of melanogenesis was provoked by regulation of tyrosinase activity and tyrosinase and MITF expression. Moreover, Poria cocos Wolf extracts contained cream improved skin tone using increase of bright value. Overall, these results provide evidence to potential agent for whitening to be used in cosmetic products.

  7. How natural are 'natural herbal remedies'? A Saudi perspective.

    PubMed

    Bogusz, Maciej J; al Tufail, Mohammed; Hassan, Huda

    2002-01-01

    There is a rapidly growing trend in the consumption of herbal remedies in industrialised and developing countries. Users of herbal remedies are at risk of toxicity and adverse interactions of herbal preparations due to their frequent contamination with metals and adulteration with synthetic drugs. The purpose of this study was to assess the quality of herbal remedies present on the market in Saudi Arabia in recent years. 247 herbal remedies and related preparations were examined from 2000-2001 at the Toxicology Laboratory, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia. Herbal powder samples were the most common sample type examined (n = 80), followed by complete, packed preparations (n = 59), single undescribed capsules or pills (n = 46), loose plant leaves or seeds (n = 28), creams (n = 18) and liquid or jelly samples (n = 16). All samples were subjected to toxicological screening for organic substances using gas chromatographic-mass spectrometric analysis, screening for heavy metals (arsenic, mercury, and lead) using inductive coupled plasma-mass spectrometry and microbiological examination. The preparations analysed were used to treat the following indications: leukaemia and other forms of cancer (n = 22); obesity (n = 18); diabetes mellitus (n = 14); rheumatic disorders (n = 14); skin pigmentation problems (n = 11); or to enhance male sexual activity (n = 9). In 123 cases, the indication of use was not known. 39 samples contained high concentrations of heavy metals. This was particularly striking in remedies used to treat leukaemia (arsenic content of 522-161,600 ppm) and in creams for whitening skin (mercury content of 5,700-126,000 ppm). Eight preparations contained synthetic drugs (e.g. benzodiazepines and tricyclic antidepressants in sedative preparations, cyproheptadine in a remedy to gain bodyweight, ibuprofen and dipyrone in herbal capsules used to treat rheumatism). 18 samples were contaminated with micro-organisms. 14

  8. [Effects of combined natural hirudin and hyperbaric oxygen therapy on survival of transplanted random-pattern skin flap in rats].

    PubMed

    Cai, Jieyun; Lin, Bojie; Pan, Xinyuan; Cui, Jia; Pradhan, Rohan; Yin, Guoqian

    2018-04-01

    To investigate the effect of natural hirudin combined with hyperbaric oxygen therapy on the survival of transplanted random-pattern skin flap in rats. A random-pattern skin flap in size of 10.0 cm×2.5 cm was elevated on the dorsum of 72 Sprague Dawley rats. Then the 72 rats were randomly divided into 4 groups ( n =18) according to the therapy method. At immediate and within 4 days after operation, the rats were treated with normal saline injection in control group, normal saline injection combined with hyperbaric oxygen treatment in hyperbaric oxygen group, the natural hirudin injection in natural hirudin group, and the natural hirudin injection combined with hyperbaric oxygen treatment in combined group. The flap survival was observed after operation, and survival rate was evaluated at 6 days after operation. The skin samples were collected for histological analysis, microvessel density (MVD) measurement, and evaluation of tumor necrosis factor α (TNF-α) expression level by the immunohistochemical staining at 2 and 4 days after operation. Partial necrosis occurred in each group after operation, and the flap in combined group had the best survival. The survival rate of flap was significantly higher in hyperbaric oxygen group, natural hirudin group, and combined group than that in control group, and in combined group than in hyperbaric oxygen group and natural hirudin group ( P <0.05). There was no significant difference between hyperbaric oxygen group and natural hirudin group ( P >0.05). At 2 days, more microvascular structure was observed in hyperbaric oxygen group, natural hirudin group, and combined group in comparison with control group; while plenty of inflammatory cells infiltration in all groups. At 4 days, the hyperbaric oxygen group, natural hirudin group, and the combined group still showed more angiogenesis. Meanwhile, there was still infiltration of inflammatory cells in control group, inflammatory cells in the other groups were significantly

  9. [Simultaneous determination of six fluorescent whitening agents in plastic and paper packaging materials by high performance liquid chromatography].

    PubMed

    Zhang, Juzhou; Ji, Shuilin; Cai, Huimei; Li, Jing; Wang, Yongxin; Wang, Jingqiu

    2017-11-08

    A novel analytical method was developed for the simultaneous determination of six fluorescent whitening agents (FWAs:FWA 135, FWA 184, FWA 185, FWA 199, FWA 378 and FWA 393) in paper and plastic food packaging materials by high performance liquid chromatography with fluorescence detection (HPLC-FLD). The sample was extracted with mixed solution of chloroform and acetonitrile (3:7, v/v), then cleaned up by HLB solid phase extraction column. Qualitative and quantitative analyses were carried out by HPLC. The sample was separated on a Phenomenex C18 column using acetonitrile and 5 mmol/L ammonium acetate aqueous solution as mobile phases. The results indicated that the linear range of FWA393 was 15-1500 μg/L and the linear ranges of the other five FWAs were 5-500 μg/L with correlation coefficients greater than 0.999. The recoveries in spiked samples were between 80.4% and 125.0% with RSDs ( n =6) of 1%-13%. Furthermore, this method was applied to analyze 12 samples in the market to verify the practicality of the method. The method showed the advantages of simplicity, high recovery and good precision, and is suitable for the detection of the six fluorescent whitening agents in food packaging materials.

  10. Two different approaches in skin cancer therapy: using a photosensitizer/a natural product

    NASA Astrophysics Data System (ADS)

    Abraham, Annie; Gayathri, Devi D.; Cibin, T. R.; Ramaiah, D.

    2010-02-01

    This paper deals with two potential modes for the treatment of skin cancer-one a novel approach using a squaraine dye and the other using a natural product- the flavonoid fraction of Saraca asoka. Squaraine dye is a photosensitizing agent, which is preferentially taken up and retained by the tumor cells and when irradiated with high power visible light results in the selective destruction of the tumor cells by photodynamic therapy. The uniqueness of this mode of treatment lies in the selective destruction of tumor cells without affecting the neighbouring normal cells, which is much advantageous over radiation therapy now frequently used. The chemopreventive and therapeutic effects of the plant component are explored as well. The experimental models were Swiss albino mice in which skin tumor was induced by DMBA. Marked reduction in tumor volume and burden in the treated groups were observed. The reversal of biochemical enzyme markers like rhodanese, myeloperoxidase, β-D glucuronidase, lactate dehydrogenase, hexokinase and sialic acid to near normal levels were observed in the PDT and flavonoid fraction treated groups. The live photographs of the experimental animals and histopathological data further support the obtained results. The study assumes importance as it combines a traditional treatment mode and a novel aspect in cancer therapy using the same experimental models. Also this is the first report on PDT using a squaraine dye for skin cancer therapy in vivo.

  11. A new dermocosmetic containing retinaldehyde, delta-tocopherol glucoside and glycylglycine oleamide for managing naturally aged skin: results from in vitro to clinical studies

    PubMed Central

    Rouvrais, Céline; Bacqueville, Daniel; Bogdanowicz, Patrick; Haure, Marie-José; Duprat, Laure; Coutanceau, Christine; Castex-Rizzi, Nathalie; Duplan, Hélène; Mengeaud, Valérie; Bessou-Touya, Sandrine

    2017-01-01

    Introduction Natural aging of skin tissues, the addition of the cumulative action of the time and radiation exposure result in skin atrophy, wrinkles and degeneration of the extracellular matrix (ECM). The aim of the study was to investigate the beneficial effect of a combination containing retinaldehyde (RAL), delta-tocopherol glucoside (delta-TC) and glycylglycine ole-amide (GGO) and of a dermocosmetic containing the combination. Materials and methods The protective effect of the combination was assessed through in vitro gene expression of ultraviolet (UV)-irradiated fibroblasts. A skin aging assay using UV light on ex vivo skin samples and a clinical study conducted in 36 women aged from 35 to 55 years with a minimum of level 4 to a maximum of level 6 on the crow’s feet photoscale assessed the antiaging effect of the dermocosmetic. Results When added to UV-irradiated fibroblasts, the combination substantially improved the ECM in activating the elastin fiber production (fibrillin 2, fibulin 1 and 5 and lysyl oxidase-like 2) as well as that of proteins involved in the cellular ECM interactions (integrin b1, paxillin and actin a2). An ex vivo photodamaged human skin model showed that the dermocosmetic formulation containing the combination of the active ingredients protected the elastic network against UV-induced alterations including both elastin and fibrillin-rich fibers in the dermis. A daily application of the dermocosmetic for 2 months on naturally aged skin resulted in a statistically significant improvement (p<0.05) of visible signs of aging comprising crow’s feet, wrinkles and periocular fine lines. Finally, the formulation was well tolerated. Conclusion The dermocosmetic containing RAL, delta-TC and GGO provides a substantial benefit in the daily care of naturally aged skin in women aged 35–55 years. PMID:28203099

  12. Topical treatment with pterostilbene, a natural phytoalexin, effectively protects hairless mice against UVB radiation-induced skin damage and carcinogenesis.

    PubMed

    Sirerol, J Antoni; Feddi, Fatima; Mena, Salvador; Rodriguez, María L; Sirera, Paula; Aupí, Miguel; Pérez, Salvador; Asensi, Miguel; Ortega, Angel; Estrela, José M

    2015-08-01

    The aim of our study was to investigate in the SKH-1 hairless mouse model the effect of pterostilbene (Pter), a natural dimethoxy analog of resveratrol (Resv), against procarcinogenic ultraviolet B radiation (UVB)-induced skin damage. Pter prevented acute UVB (360 mJ/cm(2))-induced increase in skin fold, thickness, and redness, as well as photoaging-associated skin wrinkling and hyperplasia. Pter, but not Resv, effectively prevented chronic UVB (180 mJ/cm(2), three doses/week for 6 months)-induced skin carcinogenesis (90% of Pter-treated mice did not develop skin carcinomas, whereas a large number of tumors were observed in all controls). This anticarcinogenic effect was associated with (a) maintenance of skin antioxidant defenses (i.e., glutathione (GSH) levels, catalase, superoxide, and GSH peroxidase activities) close to control values (untreated mice) and (b) an inhibition of UVB-induced oxidative damage (using as biomarkers 8-hydroxy-2'-deoxyguanosine, protein carbonyls, and isoprostanes). The molecular mechanism underlying the photoprotective effect elicited by Pter was further evaluated using HaCaT immortalized human keratinocytes and was shown to involve potential modulation of the Nrf2-dependent antioxidant response. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. In vivo measurement of skin surface strain and sub-surface layer deformation induced by natural tissue stretching.

    PubMed

    Maiti, Raman; Gerhardt, Lutz-Christian; Lee, Zing S; Byers, Robert A; Woods, Daniel; Sanz-Herrera, José A; Franklin, Steve E; Lewis, Roger; Matcher, Stephen J; Carré, Matthew J

    2016-09-01

    Stratum corneum and epidermal layers change in terms of thickness and roughness with gender, age and anatomical site. Knowledge of the mechanical and tribological properties of skin associated with these structural changes are needed to aid in the design of exoskeletons, prostheses, orthotics, body mounted sensors used for kinematics measurements and in optimum use of wearable on-body devices. In this case study, optical coherence tomography (OCT) and digital image correlation (DIC) were combined to determine skin surface strain and sub-surface deformation behaviour of the volar forearm due to natural tissue stretching. The thickness of the epidermis together with geometry changes of the dermal-epidermal junction boundary were calculated during change in the arm angle, from flexion (90°) to full extension (180°). This posture change caused an increase in skin surface Lagrange strain, typically by 25% which induced considerable morphological changes in the upper skin layers evidenced by reduction of epidermal layer thickness (20%), flattening of the dermal-epidermal junction undulation (45-50% reduction of flatness being expressed as Ra and Rz roughness profile height change) and reduction of skin surface roughness Ra and Rz (40-50%). The newly developed method, DIC combined with OCT imaging, is a powerful, fast and non-invasive methodology to study structural skin changes in real time and the tissue response provoked by mechanical loading or stretching. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Skin photoprotection by natural polyphenols: anti-inflammatory, antioxidant and DNA repair mechanisms.

    PubMed

    Nichols, Joi A; Katiyar, Santosh K

    2010-03-01

    Epidemiological, clinical and laboratory studies have implicated solar ultraviolet (UV) radiation in various skin diseases including, premature aging of the skin and melanoma and non-melanoma skin cancers. Chronic UV radiation exposure-induced skin diseases or skin disorders are caused by the excessive induction of inflammation, oxidative stress and DNA damage, etc. The use of chemopreventive agents, such as plant polyphenols, to inhibit these events in UV-exposed skin is gaining attention. Chemoprevention refers to the use of agents that can inhibit, reverse or retard the process of these harmful events in the UV-exposed skin. A wide variety of polyphenols or phytochemicals, most of which are dietary supplements, have been reported to possess substantial skin photoprotective effects. This review article summarizes the photoprotective effects of some selected polyphenols, such as green tea polyphenols, grape seed proanthocyanidins, resveratrol, silymarin and genistein, on UV-induced skin inflammation, oxidative stress and DNA damage, etc., with a focus on mechanisms underlying the photoprotective effects of these polyphenols. The laboratory studies conducted in animal models suggest that these polyphenols have the ability to protect the skin from the adverse effects of UV radiation, including the risk of skin cancers. It is suggested that polyphenols may favorably supplement sunscreens protection, and may be useful for skin diseases associated with solar UV radiation-induced inflammation, oxidative stress and DNA damage.

  15. Investigating the effect of various extracting solvents on the potential use of red-apple skin (Malus domestica) as natural sensitizer for dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Saputro, Aldhi; Mizan, Adlan; Sofyan, Nofrijon; Yuwono, Akhmad Herman

    2017-03-01

    In the current investigation, the natural dye extracted from red-apple (Malus domestica) skin was used as natural sensitizer for dye sensitized solar cell (DSSC) application. The present study was specifically aimed at observing the effect of different solvents, i.e. deionized water, ethanol, and acidified ethanol, on the performance of the natural dye and thus the DSSC. For synthesis purposes, red-apple skin was peeled off, dried, crushed and furthermore extracted with ratio red-apple skin powder to solvent 1:20 w/v for 2 hours at 50°C under mechanical stirring. Subsequently, the resulting natural dyes with different solvents were examined by Fourier transform infrared (FTIR) to analyze their functional groups, UV-Vis spectroscopy to observe their absorption spectra for a wide range of wavelength, while TiO2 nanoparticle used as the semiconductor oxide layer in the device was characterized by field emission scanning electron microscope (FESEM). The FTIR results showed that the red-apple skin has anthocyanin group which functions as the sensitizer agent for photon energy absorption from the sunlight. The UV-Vis spectroscopy results showed that ethanol solvent has higher absorption of sunlight wavelength as compared to those of deionized water and acidified ethanol solvents. The performance test of the fabricated DSSC showed the prototype made of the red apple skin dye extracted by ethanol solvent can provide the highest open circuit voltage (Voc) up to 324 mV and efficiency around 0.046%. On the basis of investigation, it has been found that ethanol was the best solvent to extract anthocyanin from the red-apple skin.

  16. The functional property of royal jelly 10-hydroxy-2-decenoic acid as a melanogenesis inhibitor.

    PubMed

    Peng, Chi-Chung; Sun, Hui-Tzu; Lin, I-Ping; Kuo, Ping-Chung; Li, Jen-Chieh

    2017-08-09

    It has been reported that royal jelly would reduce melanin synthesis and inhibit the expression of melanogensis related proteins and genes. In this study, we evaluate the anti-melanogenic and depigmenting activity of 10-hydroxy-2-decenoic acid (10-HDA) from royal jelly of Apis mellifera. In this study, we assesses the 10-HDA whitening activity in comparison with the changes in the intracellular tyrosinase activity, melanin content and melanin production related protein levles in B16F1 melanoma cells after treating with 10-HDA. Furthermore, the skin whitening effect was evaluated by applying a cream product containing with 0.5%, 1% and 2% of 10-HDA onto the skin of mice (C57BL/6 J) for 3 week to observe the effect of DL*-values. The results showed that 10-HDA inhibited the MITF protein expression (IC50 0.86 mM) in B16F1 melanoma cells. Western blot analysis revealed that 10-HDA inhibited the activity of tyrosinase and the expression of tyrosinase-related protein 1 (TRP-1), TRP-2, and microphthalmia-associated transcription factor (MITF) in B16F1 melanoma cells. In addition, the 10-HDA was applied on the skin of mice show significantly increased the average skin-whitening index (L value). The validation data indicated the potential of 10-HDA for use in suppressing skin pigmentation. The 10-HDA is proposed as a candidate to inhibit melanogenesis, thus it could be developed as cosmetics skin care products.

  17. Dual functional bioactive-peptide, AIMP1-derived peptide (AdP), for anti-aging.

    PubMed

    Kim, Jina; Kang, Sujin; Kwon, HanJin; Moon, HoSang; Park, Min Chul

    2018-06-19

    Human skin aging is caused by several factors, such as UV irradiation, stress, hormone, and pollution. Wrinkle formation and skin pigmentation are representative features of skin aging. Although EGF and arbutin are used as anti-wrinkle and skin whitening agents, respectively, they have adverse effects on skin. When more cosmeceutical ingredients are added to cosmetic product, adverse effects are also accumulated. For these reasons, multifunctional and safe cosmetic ingredients are in demand. The aim of the present study is to investigate the novel anti-aging agents, AIMP1-derived peptide (AdP, INCI name: sh-oligopeptide-5/sh-oligopeptide SP) for cosmetic products. To assess the anti-wrinkle effect of AdP, collagen type I synthesis and fibroblast proliferation were determined on human fibroblasts. The anti-wrinkle effect of AdP was examined by ELISA and cell titer glo assay. To assess the whitening, melanin content and tyrosinase activity were determined on melanocytes. The whitening effect of AdP was examined by melanin measurement and enzyme activity assay. The safety of AdP was determined by cytotoxicity and immunogenicity, CCK-8 and TNF-α ELISA assay, respectively. AdP treatment induced the collagen type I synthesis and fibroblast proliferation. Also, AdP treatment inhibited melanin synthesis by regulating tyrosinase activity. The anti-aging effect of AdP is more potent than EGF and albutin. AdP did not show adverse effects. These results show that AdP can be dual functional and safe cosmeceutical agent to prevent skin aging. © 2018 Wiley Periodicals, Inc.

  18. Skin condition measurement by using multispectral imaging system (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Jung, Geunho; Kim, Sungchul; Kim, Jae Gwan

    2017-02-01

    There are a number of commercially available low level light therapy (LLLT) devices in a market, and face whitening or wrinkle reduction is one of targets in LLLT. The facial improvement could be known simply by visual observation of face, but it cannot provide either quantitative data or recognize a subtle change. Clinical diagnostic instruments such as mexameter can provide a quantitative data, but it costs too high for home users. Therefore, we designed a low cost multi-spectral imaging device by adding additional LEDs (470nm, 640nm, white LED, 905nm) to a commercial USB microscope which has two LEDs (395nm, 940nm) as light sources. Among various LLLT skin treatments, we focused on getting melanin and wrinkle information. For melanin index measurements, multi-spectral images of nevus were acquired and melanin index values from color image (conventional method) and from multi-spectral images were compared. The results showed that multi-spectral analysis of melanin index can visualize nevus with a different depth and concentration. A cross section of wrinkle on skin resembles a wedge which can be a source of high frequency components when the skin image is Fourier transformed into a spatial frequency domain map. In that case, the entropy value of the spatial frequency map can represent the frequency distribution which is related with the amount and thickness of wrinkle. Entropy values from multi-spectral images can potentially separate the percentage of thin and shallow wrinkle from thick and deep wrinkle. From the results, we found that this low cost multi-spectral imaging system could be beneficial for home users of LLLT by providing the treatment efficacy in a quantitative way.

  19. Repeat tuberculin skin testing leads to desensitisation in naturally infected tuberculous cattle which is associated with elevated interleukin-10 and decreased interleukin-1 beta responses.

    PubMed

    Coad, Michael; Clifford, Derek; Rhodes, Shelley G; Hewinson, R Glyn; Vordermeier, H Martin; Whelan, Adam O

    2010-01-01

    The principal surveillance tool used to control bovine tuberculosis in cattle is the removal of animals that provide a positive response to the tuberculin skin-test. In this study we performed a longitudinal investigation of the immunological and diagnostic consequences of repeated short-interval skin-tests in cattle naturally infected with Mycobacterium bovis. Tuberculin skin-test positive cattle were subjected to up to four further intradermal comparative cervical skin-tests at approximately 60-day intervals. A significant progressive reduction in the strength of the skin-test was observed after successive tests. In contrast, the magnitude of interferon-gamma (IFN-gamma) responses was not influenced by repeat skin-testing either transiently around the time of each skin-test or longitudinally following repeated tests. A significant boost in blood interleukin-10 (IL-10) production was observed within 3 days following each skin-test although the magnitude of this boosted response returned to lower levels by day 10 post-test. The application of a novel multiplex assay to simultaneously measure seven cytokines and chemokines also identified that skin-testing resulted in a significant and progressive reduction in antigen specific interleukin-1beta (IL-1beta) whilst confirming stable IFN-gamma and elevated IL-10 responses in the blood. Therefore, we have demonstrated that in cattle naturally infected with M. bovis, repeat short-interval skin-testing can lead to a progressive reduction in skin-test responsiveness which has potential negative consequences for the detection of infected animals with marginal or inconclusive skin-test responses. The desensitising effect is associated with decreased IL-1beta and elevated IL-10 responses, but importantly, does not influence antigen specific IFN-gamma responses. INRA, EDP Sciences, 2009

  20. Effect of a New Bleaching Gel on Tooth Whitening.

    PubMed

    Barry, T N; Bailey, C W; Ashcraft-Olmscheid, D; Vandewalle, K S

    The purpose of this study was to compare the whitening efficacy of a novel bleaching agent containing a unique tribarrel hydremide-peroxide gel (KöR) with a traditional bleaching system of hydrogen peroxide or carbamide peroxide (Opalescence). Bovine incisors were mounted into a custom resin, arch-shaped mounting device. Four groups of 10 teeth were created using mounting devices containing five teeth each. The in-office and home bleaching gels of KöR and Opalescence were applied to the teeth alone and in trays to simulate a combination of in-office and home bleaching or home bleaching only. Spectrophotometer readings of L* a* b* were performed at baseline, the end of active bleaching (immediate), and three and six months postbleaching. Immediately postbleaching, the use of Opalescence gel resulted in greater change in ΔE* and Δb* (less yellow) for combined and home bleaching techniques compared with KöR. After six months, Opalescence had significantly greater ΔE* and Δb* compared with KöR for home bleaching only. There was no significant difference in ΔL* between Opalescence and KöR at any time period with either technique.

  1. The influence of tooth colour on the perceptions of personal characteristics among female dental patients: comparisons of unmodified, decayed and 'whitened' teeth.

    PubMed

    Kershaw, S; Newton, J T; Williams, D M

    2008-03-08

    Physical appearance plays a key role in human social interaction and the smile and teeth are important features in determining the attractiveness of a face. Furthermore, the mouth is thought to be important in social interactions. The purpose of this study was to determine the relationship between tooth colour and social perceptions. Cross-sectional survey. One hundred and eighty female participants viewed one of six images, either a male or a female digitally altered to display one of three possible dental statuses (unmodified, decayed, or whitened). The images were rated on four personality traits: social competence (SC), intellectual ability (IA), psychological adjustment (PA), and relationship satisfaction (RS). Decayed dental appearance led to more negative judgements over the four personality categories. Whitened teeth led to more positive appraisals. The gender of the image and the demographic background of the participant did not have a significant effect on appraisals. Tooth colour exerts an influence on social perceptions. The results may be explained by negative beliefs about dental decay, such as its link with poor oral hygiene.

  2. High levels of hydrogen peroxide in overnight tooth-whitening formulas: effects on enamel and pulp.

    PubMed

    Pugh, George; Zaidel, Lynette; Lin, Nora; Stranick, Michael; Bagley, Daniel

    2005-01-01

    Limited data are available to assess the safety of high levels of hydrogen peroxide in overnight tooth-whitening formulas. The purpose of this study was to assess the effects of hydrogen peroxide on enamel microhardness, pulp penetration, and enamel morphology. Colgate Platinum Professional Overnight Whitening System (Colgate Oral Pharmaceuticals, Inc., Canton, MA, USA) (10% carbamide peroxide, equivalent to 3.5% hydrogen peroxide) was compared with two prototype formulations containing either 7.0% or 12.0% hydrogen peroxide. In the pulp chamber studies, human extracted teeth were exposed to 3.5%, 7.0%, or 12.0% hydrogen peroxide for 30 minutes, 4 hours, or 7 hours. Microhardness, electron spectroscopy for chemical analysis, and atomic force microscopy evaluations were made from enamel blocks cut from human extracted molars. The enamel blocks were evaluated following 14 7-hour treatments (98 h total). At 7 hours' post-treatment, hydrogen peroxide penetrated the pulp chamber at 23.12 +/- 10.09, 24.58 +/- 6.90, and 26.39 +/- 5.43 microg for 3.5%, 7.0%, and 12.0% hydrogen peroxide, respectively. With regard to enamel morphology, pulp penetration, microhardness, and elemental composition, no statistically significant differences were observed between treatment groups following 98 hours of treatment. Hydrogen peroxide does not adversely affect enamel morphology or microhardness. The levels recovered in pulp indicate that hydrogen peroxide is not expected to inhibit pulpal enzymes. Overnight tray products containing levels of hydrogen peroxide of 3.5%, 7.0%, and 12.0% are not expected to adversely affect the enamel or pulpal enzymes. Additional safety studies are needed to assess the potential for tooth sensitivity and gingival irritation.

  3. Real-Time Spatio-Temporal Twice Whitening for MIMO Energy Detector

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Humble, Travis S; Mitra, Pramita; Barhen, Jacob

    2010-01-01

    While many techniques exist for local spectrum sensing of a primary user, each represents a computationally demanding task to secondary user receivers. In software-defined radio, computational complexity lengthens the time for a cognitive radio to recognize changes in the transmission environment. This complexity is even more significant for spatially multiplexed receivers, e.g., in SIMO and MIMO, where the spatio-temporal data sets grow in size with the number of antennae. Limits on power and space for the processor hardware further constrain SDR performance. In this report, we discuss improvements in spatio-temporal twice whitening (STTW) for real-time local spectrum sensing by demonstratingmore » a form of STTW well suited for MIMO environments. We implement STTW on the Coherent Logix hx3100 processor, a multicore processor intended for low-power, high-throughput software-defined signal processing. These results demonstrate how coupling the novel capabilities of emerging multicore processors with algorithmic advances can enable real-time, software-defined processing of large spatio-temporal data sets.« less

  4. The pathogen Batrachochytrium dendrobatidis disturbs the frog skin microbiome during a natural epidemic and experimental infection

    PubMed Central

    Jani, Andrea J.; Briggs, Cheryl J.

    2014-01-01

    Symbiotic microbial communities may interact with infectious pathogens sharing a common host. The microbiome may limit pathogen infection or, conversely, an invading pathogen can disturb the microbiome. Documentation of such relationships during naturally occurring disease outbreaks is rare, and identifying causal links from field observations is difficult. This study documented the effects of an amphibian skin pathogen of global conservation concern [the chytrid fungus Batrachochytrium dendrobatidis (Bd)] on the skin-associated bacterial microbiome of the endangered frog, Rana sierrae, using a combination of population surveys and laboratory experiments. We examined covariation of pathogen infection and bacterial microbiome composition in wild frogs, demonstrating a strong and consistent correlation between Bd infection load and bacterial community composition in multiple R. sierrae populations. Despite the correlation between Bd infection load and bacterial community composition, we observed 100% mortality of postmetamorphic frogs during a Bd epizootic, suggesting that the relationship between Bd and bacterial communities was not linked to variation in resistance to mortal disease and that Bd infection altered bacterial communities. In a controlled experiment, Bd infection significantly altered the R. sierrae microbiome, demonstrating a causal relationship. The response of microbial communities to Bd infection was remarkably consistent: Several bacterial taxa showed the same response to Bd infection across multiple field populations and the laboratory experiment, indicating a somewhat predictable interaction between Bd and the microbiome. The laboratory experiment demonstrates that Bd infection causes changes to amphibian skin bacterial communities, whereas the laboratory and field results together strongly support Bd disturbance as a driver of bacterial community change during natural disease dynamics. PMID:25385615

  5. Alp Rose stem cells, olive oil squalene and a natural alkyl polyglucoside emulsifier: Are they appropriate ingredients of skin moisturizers - in vivo efficacy on normal and sodium lauryl sulfate - irritated skin?.

    PubMed

    Filipović, Mila; Gledović, Ana; Lukić, Milica; Tasić-Kostov, Marija; Isailović, Tanja; Pantelić, Ivana; Vuleta, Gordana; Savić, Snežana

    2016-11-01

    Since skin moisturization may be achieved by both actives and chosen carrier, plant stem cells, squalene and natural alkyl polyglucoside emulsifier may be potential components of contemporary cosmetic products. The aim of the study was in vivo evaluation of the skin irritation potential and the efficacy of Alpine Rose stem cells incorporated into li-posomes and olive oil squalene as ingredients of moisturizing creams, with respect to the novel emulsifier used for creams’ stabilization. With the employment of noninvasive skin biophysical measurements, skin hydration (EC), transepi-dermal water loss (TEWL), erythema index (EI) and viscoelas-ticity were measured on 76 healthy volunteers. In the first phase, skin irritation after a 24-hour occlusion and the long-term efficacy of creams (a 21-day study) on healthy skin were evaluated. Phase II of the study focused on the cream efficacy assessment after a 6-day treatment of sodium lauryl sulfate-irritated skin. After a 24-hour occlusion, there were no significant changes in the EI for any tested sample. In the second phase of the study, the EI was not significantly altered for the cream containing squalene, while the application of all active samples resulted in a significant reduction of TEWL. In both phases of the study an EC increase was recorded, espe-cially for the squalene-containing cream. Due to the lack of skin irritation and skin barrier impairment along with the marked hydration effect, it could be said that the in-vestigated actives incorporated into alkyl polyglucoside emulsi-fier-stabilized creams may be safely applied as ingredients for "tailor-made" cosmetic moisturizers intended for normal and dry skin care, whereas olive oil squalene could be used for the treatment of irritated or sensitive skin as well. [Projekat Ministarstva nauke Republike Srbije, br. TR34031

  6. The active natural anti-oxidant properties of chamomile, milk thistle, and halophilic bacterial components in human skin in vitro.

    PubMed

    Mamalis, Andrew; Nguyen, Duc-Huy; Brody, Neil; Jagdeo, Jared

    2013-07-01

    The number of skin cancers continues to rise, accounting for approximately 40% of all cancers reported in the United States and approximately 9,500 deaths per year. Studies have shown reactive oxygen species (ROS) type free radicals are linked to skin cancer and aging. Therefore, it is important for us to identify agents that have anti-oxidant properties to protect skin against free radical damage. The purpose of this research is to investigate the anti-oxidant properties of bisabolol, silymarin, and ectoin that are components from chamomile, milk thistle, and halophilic bacteria, respectively. We measured the ability of bisabolol, silymarin, and ectoin to modulate the hydrogen peroxide (H2O2)-induced upregulation of ROS free radicals in normal human skin fibroblasts in vitro. Using a flow cytometry-based assay, we demonstrated that varying concentrations of these natural components were able to inhibit upregulation of H2O2-generated free radicals in human skin fibroblasts in vitro. Our results indicate components of chamomile, milk thistle, and halophilic bacteria exhibit anti-oxidant capabilities and warrant further study in clinical trials to characterize their anti-cancer and anti-aging capabilities.

  7. 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

  8. Temporary skin grafts based on hybrid graphene oxide-natural biopolymer nanofibers as effective wound healing substitutes: pre-clinical and pathological studies in animal models.

    PubMed

    Mahmoudi, N; Eslahi, N; Mehdipour, A; Mohammadi, M; Akbari, M; Samadikuchaksaraei, A; Simchi, A

    2017-05-01

    In recent years, temporary skin grafts (TSG) based on natural biopolymers modified with carbon nanostructures have received considerable attention for wound healing. Developments are required to improve physico-mechanical properties of these materials to match to natural skins. Additionally, in-deep pre-clinical examinations are necessary to ensure biological performance and toxicity effect in vivo. In the present work, we show superior acute-wound healing effect of graphene oxide nanosheets embedded in ultrafine biopolymer fibers (60 nm) on adult male rats. Nano-fibrous chitosan-based skin grafts crosslinked by Genepin with physico-mechanical properties close to natural skins were prepared by electrospinning of highly concentrated chitosan- polyvinylpyrrolidone solutions containing graphene oxide (GO) nanosheets. No surfactants and organic solvents were utilized to ensure high biocompatibility of the fibrous structure. In vitro evaluations by human skin fibroblast cells including live and dead assay and MTT results show that GO promote cell viability of porous nanofibrous membrane while providing enhanced bactericidal capacity. In vivo studies on rat's skin determine accelerated healing effect, i.e. a large open wound (1.5 × 1.5 cm 2 ) is fully regenerated after 14-day of post operation while healing is observed for sterile gauze sponge (as the control). Pathological studies support thick dermis formation and complete epithelialization in the presence of 1.5 wt% GO nanosheets. Over 99% wound healing occurs after 21 days for the injury covered with TSG containing 1.5 wt% GO while this would takes weeks for the control. Therefore, the developed materials have a high potential to be used as TSG as pre-clinical testing has shown.

  9. The clinical anticalculus efficacy of a tartar control whitening dentifrice for the prevention of supragingival calculus in a three-month study.

    PubMed

    Sowinski, J; Petrone, D M; Battista, G; Petrone, M E; Crawford, R; Patel, S; DeVizio, W; Chaknis, P; Volpe, A R; Proskin, H M

    1999-01-01

    The objective of this double-blind clinical study was to compare the effect of a new dentifrice (Colgate Tartar Control Plus Whitening Fluoride Toothpaste) for the prevention of supragingival calculus, with that of a commercially available calculus-inhibiting dentifrice (Crest Tartar Control Toothpaste). The study involved adult male and female subjects who had pre-qualified for participation by developing sufficient supragingival calculus (greater than 7.0 on the Volpe-Manhold Calculus Index) during an eight-week screening period. Subjects received a full oral prophylaxis, and were stratified into two treatment groups balanced for age, sex and qualifying calculus score. Subjects were instructed to brush their teeth twice daily (morning and evening) for one minute with their assigned dentifrice using a soft-bristled toothbrush. Examinations for dental calculus were performed after twelve weeks' use of the study dentifrices, using the Volpe-Manhold Calculus Index, Fifty-eight (58) subjects complied with the protocol and completed the entire study. The Colgate Tartar Control Plus Whitening group exhibited a statistically significant (p < 0.001) 34.6% reduction in mean calculus score compared to the Crest Tartar Control group.

  10. A novel method for real-time skin impedance measurement during radiofrequency skin tightening treatments.

    PubMed

    Harth, Yoram; Lischinsky, Daniel

    2011-03-01

    The thermal effects of monopolar and bipolar radiofrequency (RF) have been proven to be beneficial in skin tightening. Nevertheless, these effects were frequently partial or unpredictable because of the uncontrolled nature of monopolar or unipolar RF and the superficial nature of energy flow for bipolar or tripolar configurations. One of the hypotheses for lack or predictability of efficacy of the first-generation RF therapy skin tightening systems is lack of adaptation of delivered power to differences in individual skin impedance. A novel multisource phase-controlled system was used (1 MHz, power range 0-65 W) for treatment and real-time skin impedance measurements in 24 patients (EndyMed PRO™; EndyMed, Cesarea, Israel). This system allows continuous real-time measurement of skin impedance delivering constant energy to the patient skin independent of changes in its impedance. More than 6000 unique skin impedance measurements on 22 patients showed an average session impedance range was 215-584 Ohm with an average of 369 Ohm (standard deviation of 49 Ohm). Analyzing individual pulses (total of 600 readings) showed a significant decrease in impedance during the pulse. These findings validate the expected differences in skin impedance between individual patients and in the same patients during the treatment pulse. Clinical study on 30 patients with facial skin aging using the device has shown high predictability of efficacy (86.7% of patients had good results or better at 3 months' follow-up [decrease of 2 or more grades in Fitzpatrick's wrinkle scale]). The real-time customization of energy according to skin impedance allows a significantly more accurate and safe method of nonablative skin tightening with more consistent and predictable results. © 2011 Wiley Periodicals, Inc.

  11. Moisturizers: Options for Softer Skin

    MedlinePlus

    ... you have specific conditions, such as acne. For general guidelines, consider the following Normal skin. Normal skin is neither too dry nor too oily. To maintain this natural moisture balance, use a water-based moisturizer that has a ...

  12. The effect of bleaching gel and (940 nm and 980 nm) diode lasers photoactivation on intrapulpal temperature and teeth whitening efficiency.

    PubMed

    Al-Karadaghi, Tamara S; Al-Saedi, Asmaa A; Al-Maliky, Mohammed A; Mahmood, Ali S

    2016-12-01

    This in vitro study aimed to investigate the whitening efficacy of 940 nm and 980 nm diode laser photoactivation in tooth bleaching by analysing pulp chamber temperature, as well as the change in tooth colour. Root canals of thirty extracted human lower premolars were prepared. Laserwhite* 20 bleaching agent containing 38% of hydrogen peroxide was photoactivated with 7 W output power of 940 nm and 980 nm diode lasers for 120 s. Bleaching gel reduced 27-29% of the temperature from reaching the pulp chamber. For shade assessment, only the groups photoactivated using diode lasers showed statistically significant differences from control group P < 0.001. Within the studied parameters, both 940 nm and 980 nm diode lasers produced a safe pulp temperature increase. Diode laser photoactivation of bleaching gel resulted in more efficient teeth whitening. Photoactivation with 940 nm diode laser yielded the highest change in colour with only minor increase in pulp chamber temperature. © 2016 Australian Society of Endodontology Inc.

  13. Natural healing-inspired collagen-targeting surgical protein glue for accelerated scarless skin regeneration.

    PubMed

    Jeon, Eun Young; Choi, Bong-Hyuk; Jung, Dooyup; Hwang, Byeong Hee; Cha, Hyung Joon

    2017-07-01

    Skin scarring after deep dermal injuries is a major clinical problem due to the current therapies limited to established scars with poor understanding of healing mechanisms. From investigation of aberrations within the extracellular matrix involved in pathophysiologic scarring, it was revealed that one of the main factors responsible for impaired healing is abnormal collagen reorganization. Here, inspired by the fundamental roles of decorin, a collagen-targeting proteoglycan, in collagen remodeling, we created a scar-preventive collagen-targeting glue consisting of a newly designed collagen-binding mussel adhesive protein and a specific glycosaminoglycan. The collagen-targeting glue specifically bound to type I collagen in a dose-dependent manner and regulated the rate and the degree of fibrillogenesis. In a rat skin excisional model, the collagen-targeting glue successfully accelerated initial wound regeneration as defined by effective reepithelialization, neovascularization, and rapid collagen synthesis. Moreover, the improved dermal collagen architecture was demonstrated by uniform size of collagen fibrils, their regular packing, and a restoration of healthy tissue component. Collectively, our natural healing-inspired collagen-targeting glue may be a promising therapeutic option for improving the healing rate with high-quality and effective scar inhibition. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Self-reported skin colour and erythemal sensitivity vs. objectively measured constitutive skin colour in an African population with predominantly dark skin.

    PubMed

    Wright, Caradee Y; Wilkes, Marcus; du Plessis, Johan L; Reeder, Anthony I

    2015-11-01

    Skin colour is an important factor in skin-related diseases. Accurate determination of skin colour is important for disease prevention and supporting healthy sun behaviour, yet such data are lacking for dark skin types. Self-perceived, natural skin colour and sun-skin reaction were compared with objectively measured skin colour among an African population with predominantly dark skin. Unexposed skin of 556 adults (70.1% Black) was measured with a reflectance spectrophotometer to calculate an individual typology angle (°ITA). Participants reported self-perceived skin colour and erythemal sensitivity. There was a strong, positive monotonic correlation between self-reported and measured skin colour (Spearman ρ = 0.6438, P < 0.001), but only a weak correlation between self-reported erythemal sensitivity and measured skin colour (Spearman ρ = 0.2713, P < 0.001). Self-report biases in underestimation and overestimation of skin colour were evident. Many participants with 'dark brown' and 'black' skin had difficulty in classifying erythemal sensitivity. In Africa, self-reported skin colour could potentially be used in lieu of spectrophotometer measurements, but options for questions on sunburn and tanning require suitable adjustment. Our study provides evidence of range in °ITA values among residents in Africa and reinforces previous results that self-report may be reliable for determining skin colour, but not erythemal sensitivity, for dark skin individuals. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Natural rubber latex skin testing reagents: safety and diagnostic accuracy of nonammoniated latex, ammoniated latex, and latex rubber glove extracts.

    PubMed

    Hamilton, R G; Adkinson, N F

    1996-11-01

    Nonammoniated latex, ammoniated latex, and rubber glove extracts are the only sources of natural rubber (Hevea brasiliensis) latex that have potential for use as skin testing reagents in the diagnosis of latex allergy. Their diagnostic sensitivity and specificity as skin test reagents are unknown. We conducted a phase 1/2 clinical study to examine the safety and diagnostic accuracy (sensitivity and specificity) of nonammoniated latex, ammoniated latex, and rubber glove extracts as skin test extracts to identify the most efficacious source material for future skin test reagent development. Twenty-four adults not allergic to latex, 19 adults with hand dermatitis or pruritus, and 59 adults with a latex allergy were identified by clinical history. All provided blood and then received puncture skin tests and intradermal skin tests with nonammoniated latex, ammoniated latex, and rubber glove extracts from Malaysian H. brasiliensis latex by use of sequential titration. A glove provocation test and IgE anti-latex RAST were used to clarify positive history-negative skin test response and negative history-positive skin test response mismatches. All three extracts were biologically safe and sterile. After normalization to 1 mg/ml of total protein, all three extracts produced equivalent diagnostic sensitivity and specificity in puncture skin tests and intradermal skin tests at various extract concentrations. Optimal diagnostic accuracy was safely achieved at 100 micrograms/ml for intradermal skin tests (e.g., nonammoniated latex: puncture skin test sensitivity 96%, specificity 100%; intradermal skin test sensitivity 93%, specificity 96%). The presence of IgE antibody in skin was highly correlated with IgE anti-latex in serum (nonammoniated latex: r = 0.98, p < 0.001; ammoniated latex: r = 0.94, p < 0.001; rubber glove extract: r = 0.96, p < 0.001). All five available subjects with a positive history, negative skin test response, and absence of IgE antibody in serum had a

  16. [Preparation and antimicrobial effect of aromatic, natural and bacteriostatic foot wash with skin care].

    PubMed

    Gao, Su-Hua; Zhao, Guo-Xiang; Yang, Xiao-Dong; Xu, Ling-Ling

    2013-06-01

    To prepare the aromatic, natural and bacteriostatic foot wash with skin care and research the inhibition effect on the different bacteria and pathogenic fungus which cause dermatophytosis. It was prepared by using Sophoraflavescens and Dictamnus dasycarpus as materials with the addition of Aloe extract, essential oil, surfactant, etc. The antifungal and antibacterial activity was researched by the levitation liquid quantitative method. The foot wash smelled faintly scent. The use of this product can produce a rich foam. The inhibitory rate were all more than 90%. The preparation process of the foot wash was simple. It has obviously bacteriostatic and fungistatic effect.

  17. Tapinarof Is a Natural AhR Agonist that Resolves Skin Inflammation in Mice and Humans.

    PubMed

    Smith, Susan H; Jayawickreme, Channa; Rickard, David J; Nicodeme, Edwige; Bui, Thi; Simmons, Cathy; Coquery, Christine M; Neil, Jessica; Pryor, William M; Mayhew, David; Rajpal, Deepak K; Creech, Katrina; Furst, Sylvia; Lee, James; Wu, Dalei; Rastinejad, Fraydoon; Willson, Timothy M; Viviani, Fabrice; Morris, David C; Moore, John T; Cote-Sierra, Javier

    2017-10-01

    Tapinarof (GSK2894512) is a naturally derived topical treatment with demonstrated efficacy for patients with psoriasis and atopic dermatitis, although the biologic target and mechanism of action had been unknown. We demonstrate that the anti-inflammatory properties of tapinarof are mediated through activation of the aryl hydrocarbon receptor (AhR). We show that tapinarof binds and activates AhR in multiple cell types, including cells of the target tissue-human skin. In addition, tapinarof moderates proinflammatory cytokine expression in stimulated peripheral blood CD4+ T cells and ex vivo human skin, and impacts barrier gene expression in primary human keratinocytes; both of these processes are likely to be downstream of AhR activation based on current evidence. That the anti-inflammatory properties of tapinarof derive from AhR agonism is conclusively demonstrated using the mouse model of imiquimod-induced psoriasiform skin lesions. Topical treatment of AhR-sufficient mice with tapinarof leads to compound-driven reductions in erythema, epidermal thickening, and tissue cytokine levels. In contrast, tapinarof has no impact on imiquimod-induced skin inflammation in AhR-deficient mice. In summary, these studies identify tapinarof as an AhR agonist and confirm that its efficacy is dependent on AhR. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  18. Phenylalanine ab initio models for the simulation of skin natural moisturizing factor

    NASA Astrophysics Data System (ADS)

    Carvalho, B. G.; Raniero, L. J.; Martin, A. A.; Favero, P. P.

    2013-04-01

    In this study, we evaluated models that can be used to simulate amino acids in biological environments via density functional theory (DFT). The goal was to obtain realistic representations that combine computational economy and result quality when compared to experimental data. We increased the complexity of the models by using a model of an amino acid in a vacuum, followed by a water-solvated amino acid model. To consider pH variation, we simulated zwitterionic and nonionic amino acid configurations. The amino acid chosen for testing was phenylalanine, an aromatic amino acid present in high concentrations in the natural moisturizing factor of skin that plays a fundamental role in ultraviolet protection and vitiligo disease. To validate the models, vibrational modes and electronic properties were calculated and compared to experimental results.

  19. Hesperidin Suppresses Melanosome Transport by Blocking the Interaction of Rab27A-Melanophilin

    PubMed Central

    Kim, Bora; Lee, Jee-Young; Lee, Ha-Yeon; Nam, Ky-Youb; Park, JongIl; Lee, Su Min; Kim, Jin Eun; Lee, Joo Dong; Hwang, Jae Sung

    2013-01-01

    We investigated the inhibitory effects of hesperidin on melanogenesis. To find melanosome transport inhibitor from natural products, we collected the structural information of natural products from Korea Food and Drug Administration (KFDA) and performed pharmacophore-based in silico screening for Rab27A and melanophilin (MLPH). Hesperidin did not inhibit melanin production in B16F10 murine melanoma cells stimulated with α-melanocyte stimulating hormone (α-MSH), and also did not affect the catalytic activity of tyrosinase. But, hesperidin inhibited melanosome transport in melanocyte and showed skin lightening effect in pigmented reconstructed epidermis model. Therefore, we suggest that hesperidin is a useful inhibitor of melanosome transport and it might be applied to whitening agent. PMID:24244821

  20. Noise Whitening in Airborne Wind Profiling With a Pulsed 2-Micron Coherent Doppler Lidar at NASA Langley Research Center

    NASA Technical Reports Server (NTRS)

    Beyon, Jeffrey Y.; Arthur, Grant E.; Koch, Grady J.; Kavaya, Michael J.

    2012-01-01

    Two different noise whitening methods in airborne wind profiling with a pulsed 2-micron coherent Doppler lidar system at NASA Langley Research Center in Virginia are presented. In order to provide accurate wind parameter estimates from the airborne lidar data acquired during the NASA Genesis and Rapid Intensification Processes (GRIP) campaign in 2010, the adverse effects of background instrument noise must be compensated properly in the early stage of data processing. The results of the two methods are presented using selected GRIP data and compared with the dropsonde data for verification purposes.

  1. Natural Substances for Prevention of Skin Photoaging: Screening Systems in the Development of Sunscreen and Rejuvenation Cosmetics.

    PubMed

    Kostyuk, Vladimir; Potapovich, Alla; Albuhaydar, Ahmed R; Mayer, Wolfgang; De Luca, Chiara; Korkina, Liudmila

    2018-04-01

    Solar broadband UV irradiation is commonly regarded as a major causative reason for cutaneous photoaging. The pro-aging molecular pathways and cellular targets affected by UVA+UVB light in human skin have been extensively investigated. Notwithstanding growing knowledge in mechanisms of photoaging, research and development of clinically efficient, nontoxic, and sustainable topical preparations providing full physical, chemical, and biological photoprotection still remain a great challenge for pharmaceutical and cosmetic industries. In this study, we are proposing a panel of the in vitro methods for preselection of natural photoprotective substances with high photostability and low phototoxicity able of absorbing a broadband UVA+UVB irradiation (physical sunscreen), reducing UV-related overproduction of free radicals and loss of endogenous antioxidants (chemical protection), and attenuating UV-induced cytotoxicity and immune and metabolic responses (biological protection) in primary human epidermal keratinocytes and immortalized human keratinocyte cultures. Our data showed that secondary metabolites biosynthesized in plant cells in response to UV irradiation, such as phenylpropanoids and their glycosylated metabolites, aglycons and glycosylated flavonoids, and leontopodic acids, hold the best promise for complete natural topical prevention of photoaging and rejuvenation of photoaged skin. Meristem plant cell cultures elicited by solar simulating UV could be the most environmentally sustainable biotechnological source of polyphenols with combined photoprotective and antiaging properties.

  2. Natural Substances for Prevention of Skin Photoaging: Screening Systems in the Development of Sunscreen and Rejuvenation Cosmetics

    PubMed Central

    Kostyuk, Vladimir; Potapovich, Alla; Albuhaydar, Ahmed R.; Mayer, Wolfgang; De Luca, Chiara

    2018-01-01

    Abstract Solar broadband UV irradiation is commonly regarded as a major causative reason for cutaneous photoaging. The pro-aging molecular pathways and cellular targets affected by UVA+UVB light in human skin have been extensively investigated. Notwithstanding growing knowledge in mechanisms of photoaging, research and development of clinically efficient, nontoxic, and sustainable topical preparations providing full physical, chemical, and biological photoprotection still remain a great challenge for pharmaceutical and cosmetic industries. In this study, we are proposing a panel of the in vitro methods for preselection of natural photoprotective substances with high photostability and low phototoxicity able of absorbing a broadband UVA+UVB irradiation (physical sunscreen), reducing UV-related overproduction of free radicals and loss of endogenous antioxidants (chemical protection), and attenuating UV-induced cytotoxicity and immune and metabolic responses (biological protection) in primary human epidermal keratinocytes and immortalized human keratinocyte cultures. Our data showed that secondary metabolites biosynthesized in plant cells in response to UV irradiation, such as phenylpropanoids and their glycosylated metabolites, aglycons and glycosylated flavonoids, and leontopodic acids, hold the best promise for complete natural topical prevention of photoaging and rejuvenation of photoaged skin. Meristem plant cell cultures elicited by solar simulating UV could be the most environmentally sustainable biotechnological source of polyphenols with combined photoprotective and antiaging properties. PMID:28661208

  3. Natural Oil-Based Emulsion Containing Allantoin Versus Aqueous Cream for Managing Radiation-Induced Skin Reactions in Patients With Cancer: A Phase 3, Double-Blind, Randomized, Controlled Trial

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chan, Raymond Javan, E-mail: email.rchan@gmail.com; School of Nursing, Queensland University of Technology, Kelvin Grove; Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove

    Purpose: To investigate the effects of a natural oil-based emulsion containing allantoin versus aqueous cream for preventing and managing radiation-induced skin reactions. Methods and Materials: A total of 174 patients were randomized and participated in the study. Patients received either cream 1 (the natural oil-based emulsion containing allantoin) or cream 2 (aqueous cream). Skin toxicity, pain, itching, and skin-related quality of life scores were collected for up to 4 weeks after radiation treatment. Results: Patients who received cream 1 had a significantly lower average level of Common Terminology Criteria for Adverse Events at week 3 (P<.05) but had statistically higher averagemore » levels of skin toxicity at weeks 7, 8, and 9 (all P<.001). Similar results were observed when skin toxicity was analyzed by grades. With regards to pain, patients in the cream 2 group had a significantly higher average level of worst pain (P<.05) and itching (P=.046) compared with the cream 1 group at week 3; however, these differences were not observed at other weeks. In addition, there was a strong trend for cream 2 to reduce the incidence of grade 2 or more skin toxicity in comparison with cream 1 (P=.056). Overall, more participants in the cream 1 group were required to use another topical treatment at weeks 8 (P=.049) and 9 (P=.01). Conclusion: The natural oil-based emulsion containing allantoin seems to have similar effects for managing skin toxicity compared with aqueous cream up to week 5; however, it becomes significantly less effective at later weeks into the radiation treatment and beyond treatment completion (week 6 and beyond). There were no major differences in pain, itching, and skin-related quality of life. In light of these results, clinicians and patients can base their decision on costs and preferences. Overall, aqueous cream seems to be a more preferred option.« less

  4. Alleviation effect of arbutin on oxidative stress generated through tyrosinase reaction with l-tyrosine and l-DOPA

    PubMed Central

    2014-01-01

    Background Hydroxyl radical that has the highest reactivity among reactive oxygen species (ROS) is generated through l-tyrosine-tyrosinase reaction. Thus, the melanogenesis might induce oxidative stress in the skin. Arbutin (p-hydroxyphenyl-β-d-glucopyranoside), a well-known tyrosinase inhibitor has been widely used for the purpose of skin whitening. The aim of the present study was to examine if arbutin could suppress the hydroxyl radical generation via tyrosinase reaction with its substrates, l-tyrosine and l-DOPA. Results The hydroxyl radical, which was determined by an electron spin resonance-spin trapping technique, was generated by the addition of not only l-tyrosine but l-DOPA to tyrosinase in a concentration dependent manner. Arbutin could inhibit the hydroxyl radical generation in the both reactions. Conclusion It is presumed that arbutin could alleviate oxidative stress derived from the melanogenic pathway in the skin in addition to its function as a whitening agent in cosmetics. PMID:25297374

  5. Natural oils as skin permeation enhancers for transdermal delivery of olanzapine: in vitro and in vivo evaluation.

    PubMed

    Aggarwal, Geeta; Dhawan, Sanju; HariKumar, S L

    2012-03-01

    The feasibility of development of transdermal delivery system of olanzapine utilizing natural oils as permeation enhancers was investigated. Penetration enhancing potential of corn (maize) oil, groundnut oil and jojoba oil on in vitro permeation of olanzapine across rat skin was studied. The magnitude of flux enhancement factor with corn oil, groundnut oil and jojoba oil was 7.06, 5.31 and 1.9 respectively at 5mg/ml concentration in solvent system. On the basis of in vitro permeation studies, eudragit based matrix type transdermal patches of olanzapine were fabricated using optimized concentrations of natural oils as permeation enhancers. All transdermal patches were found to be uniform with respect to physical characteristics. The interaction studies carried out by comparing the results of ultraviolet, HPLC and FTIR analyses for the pure drug, polymers and mixture of drug and polymers indicated no chemical interaction between the drug and excipients. Corn oil containing unsaturated fatty acids was found to be promising natural permeation enhancer for transdermal delivery of olanzapine with greatest cumulative amount of drug permeated (1010.68 μg/cm²/h) up to 24 h and caused no skin irritation. The fabricated transdermal patches were found to be stable. The pharmacokinetic characteristics of the final optimized matrix patch (T2) were determined after transdermal application to rabbits. The calculated relative bioavailability of TDDS was 113.6 % as compared to oral administration of olanzapine. The therapeutic effectiveness of optimized transdermal system was confirmed by tranquillizing activity in rotarod and grip mice model.

  6. Quercitrin Protects Skin from UVB-induced Oxidative Damage

    PubMed Central

    Yin, Yuanqin; Li, Wenqi; Son, Yong-Ok; Sun, Lijuan; Lu, Jian; Kim, Donghern; Wang, Xin; Yao, Hua; Wang, Lei; Pratheeshkumar, Poyil; Hitron, Andrew J; Luo, Jia; Gao, Ning; Shi, Xianglin; Zhang, Zhuo

    2013-01-01

    Exposure of the skin to ultraviolet B (UVB) radiation causes oxidative damage to skin, resulting in sunburn, photoaging, and skin cancer. It is generally believed that the skin damage induced by UV irradiation is a consequence of generation of reactive oxygen species (ROS). Recently, there is an increased interest in the use of natural products as chemopreventive agents for non-melanoma skin cancer (NMSC) due to their antioxidants and anti-inflammatory properties. Quercitrin, glycosylated form of quercetin, is the most common flavonoid in nature with antioxidant properties. The present study investigated the possible beneficial effects of quercitrin to inhibit UVB irradiation-induced oxidative damage in vitro and in vivo. Our results showed that quercitrin decreased ROS generation induced by UVB irradiation in JB6 cells. Quercitrin restored catalase expression and GSH/GSSG ratio reduced by UVB exposure, two major antioxidant enzymes, leading to reductions of oxidative DNA damage and apoptosis and protection of the skin from inflammation caused by UVB exposure. The present study demonstrated that quercitrin functions as an antioxidant against UVB irradiation-induced oxidative damage to skin. PMID:23545178

  7. Infiltration and activation of acidophilic granulocytes in skin lesions of gilthead seabream, Sparus aurata, naturally infected with lymphocystis disease virus.

    PubMed

    Dezfuli, B S; Lui, A; Giari, L; Castaldelli, G; Mulero, V; Noga, E J

    2012-01-01

    Light, ultrastructural and immunocytochemical investigations were carried out on the skin of gilthead seabream, Sparus aurata L., naturally infected with lymphocystis iridovirus, to assess pathology and host cellular responses. Of 220,000 young seabream examined, 32,400 (14.7%) had clinical signs of lymphocystis and within 6 months of disease appearance, 45% of clinically affected fish had died. A subsample of 20 S. aurata (80.0 ± 12.5mm total length, mean ± S.D.), including 10 with lymphocystis on the skin and 10 clinically normal, were examined via immunohistochemistry. Affected skin displayed macroscopic, wart-like clusters of hypertrophic fibroblasts which arose from the dermis and were covered by the epithelium. Clusters were encountered on the head, trunk and fins, but there was no evidence of visceral lymphocystis. The lymphocysts were surrounded by numerous granular cells that were positive for the antimicrobial peptide (AMP) piscidin 3 and underwent intense degranulation. To identify the type of granular cells involved in this viral disease, a double immunohistochemical staining with the monoclonal antibody G7 (mAb G7), which is specific for seabream acidophilic granulocytes (AGs), and with anti-histamine (as a marker for mast cells, MCs) was applied to the skin sections of the 10 clinically normal fish and 10 fish with lymphocystis. In infected skin, the number of G7-positive cells (i.e., AGs) (18.5 ± 10.5, mean number of cells per 20,000 μm(2) ± S.D.) was significantly higher compared to their density in uninfected skin (1.4 ± 2.2) (t test, p<0.01). Notably, the AGs that infiltrated the skin lesions of infected animals were found to be degranulated and to produce the pro-inflammatory cytokine interleukin-1β. No histamine-positive granular cells (i.e., MCs) were encountered in the lymphocystis lesions. The present study shows the response of skin to lymphocystis disease virus (LCDV) and provides evidence that AGs, but not MCs, are recruited and

  8. In vitro demineralization of tooth enamel subjected to two whitening regimens.

    PubMed

    Ogura, Kayoko; Tanaka, Reina; Shibata, Yo; Miyazaki, Takashi; Hisamitsu, Hisashi

    2013-07-01

    The resistance of bleached enamel to demineralization has not been elucidated fully. In this study, the authors aimed to examine the level of in vitro demineralization of human tooth enamel after bleaching by using two common bleaching regimens: home bleaching (HB) and office bleaching (OB) with photoirradiation. The authors bleached teeth to equivalent levels by means of the two bleaching regimens. They used fluorescence spectroscopy to measure the reduction in enamel density and the release of calcium into solution after storing the treated teeth in a demineralizing solution for two weeks. They also visualized and quantified mineral distribution in demineralized bleached enamel over time by using a desktop microcomputed-tomographic analyzer. Enamel subjected to HB or to photoirradiation without bleaching showed increased demineralization. In contrast, enamel treated with OB was more resistant to demineralization. This resistance to demineralization in teeth treated with OB presumably is due to peroxide's permeating to deeper layers of enamel before being activated by photoirradiation, which enhances mineralization. The mineral distribution pattern of enamel after treatment plays a critical role in providing resistance to demineralization in whitened teeth. OB confers to enamel significant resistance to in vitro demineralization. Dentists should supervise the nightguard HB process.

  9. 'Batman excision' of ventral skin in hypospadias repair, clue to aesthetic repair (point of technique).

    PubMed

    Hoebeke, P B; De Kuyper, P; Van Laecke, E

    2002-11-01

    In the hypospadiac penis the ventral skin is poorly developed, while dorsal skin is redundant. The classical Byars' flaps are a way to use the excess dorsal skin to cover the penile shaft. The appearance after Byars' flaps however is not natural. We use a more natural looking skin allocation with superior aesthetic results. The clue in this reconstruction is an inverted triangle shaped excision of ventral skin expanding over the edges of the hooded prepuce (which makes it look like Batman). After excision of the ventral skin it is possible to close the penile skin in the midline, thus mimicking the natural raphe. In case of preputial reconstruction the excised ventral skin makes the prepuce look more natural. The trend of further refining aesthetic appearance of the hypospadiac penis often neglects the penile skin reconstruction. A technique is presented by which the total penile appearances after surgery ameliorates due to better skin reconstruction.

  10. Protective Vaccination against Papillomavirus-Induced Skin Tumors under Immunocompetent and Immunosuppressive Conditions: A Preclinical Study Using a Natural Outbred Animal Model

    PubMed Central

    Vinzón, Sabrina E.; Braspenning-Wesch, Ilona; Müller, Martin; Geissler, Edward K.; Nindl, Ingo; Gröne, Hermann-Josef

    2014-01-01

    Certain cutaneous human papillomaviruses (HPVs), which are ubiquitous and acquired early during childhood, can cause a variety of skin tumors and are likely involved in the development of non-melanoma skin cancer, especially in immunosuppressed patients. Hence, the burden of these clinical manifestations demands for a prophylactic approach. To evaluate whether protective efficacy of a vaccine is potentially translatable to patients, we used the rodent Mastomys coucha that is naturally infected with Mastomys natalensis papillomavirus (MnPV). This skin type papillomavirus induces not only benign skin tumours, such as papillomas and keratoacanthomas, but also squamous cell carcinomas, thereby allowing a straightforward read-out for successful vaccination in a small immunocompetent laboratory animal. Here, we examined the efficacy of a virus-like particle (VLP)-based vaccine on either previously or newly established infections. VLPs raise a strong and long-lasting neutralizing antibody response that confers protection even under systemic long-term cyclosporine A treatment. Remarkably, the vaccine completely prevents the appearance of benign as well as malignant skin tumors. Protection involves the maintenance of a low viral load in the skin by an antibody-dependent prevention of virus spread. Our results provide first evidence that VLPs elicit an effective immune response in the skin under immunocompetent and immunosuppressed conditions in an outbred animal model, irrespective of the infection status at the time of vaccination. These findings provide the basis for the clinical development of potent vaccination strategies against cutaneous HPV infections and HPV-induced tumors, especially in patients awaiting organ transplantation. PMID:24586150

  11. A Preliminary Analysis of the Phenomenology of Skin-Picking in Prader-Willi Syndrome

    ERIC Educational Resources Information Center

    Morgan, Jessica R.; Storch, Eric A.; Woods, Douglas W.; Bodzin, Danielle; Lewin, Adam B.; Murphy, Tanya K.

    2010-01-01

    To examine the nature and psychosocial correlates of skin-picking behavior in youth with Prader-Willi Syndrome (PWS). Parents of 67 youth (aged 5-19 years) with PWS were recruited to complete an internet-based survey that included measures of: skin-picking behaviors, the automatic and/or focused nature of skin-picking, severity of skin-picking…

  12. Kinetic release of hydrogen peroxide from different whitening products.

    PubMed

    da Silva Marques, Duarte Nuno; Silveira, Joao Miguel; Marques, Joana Rita; Amaral, Joao Almeida; Guilherme, Nuno Marques; da Mata, António Duarte

    2012-01-01

    The objective of this in vitro study was to evaluate the kinetics of hydrogen peroxide (HP) release from five different bleaching products: VivaStyle® 10% fitted tray gel, VivaStyle® 30% in-office bleaching gel, VivaStyle® Paint-On Plus paint-on bleaching varnish, Opalescence PF® 10% carbamide peroxide gel and Trèswhite Supreme™ 10% HP gel. Each product was firstly titrated for its HP content by a described method. HP release kinetics was assessed by a modified spectrophotometric technique. One sample t test was performed to test for differences between the manufacturers' claimed HP concentrations and the titrated HP content in the whitening products. Analysis of variance plus Tamhane's post hoc tests and Pearson correlation analysis were used as appropriate. Values of P < 0.05 were taken as significant. Titrated HP revealed an increased content when compared to the manufacturer's specifications for all the products tested (P < 0.05), although only products from one manufacturer produced significantly higher results. All products presented a significant (P < 0.05) and sustained release of HP. However, the product with paint-on cellulose-based matrix resulted in significantly (P < 0.05) faster kinetics when compared to other products tested. These results are consistent with manufacturers' reduced recommended application times. The results of this study suggest that modifying the matrix composition may be a viable alternative to HP concentration increase, since this may result in faster release kinetics without exposure to high HP concentrations.

  13. Infant Skin Care Products: What Are the Issues?

    PubMed

    Kuller, Joanne McManus

    2016-10-01

    Infant skin is susceptible to dryness and irritation from external factors, including topical skin care products not formulated for the infant's skin. This may increase the risk of contact dermatitis. Parents frequently express concern regarding potential harm from ingredients in skin care products and seek information. This is complicated by several skin care myths. The purpose of this literature review was to provide evidence-based information to educate parents on the use of products for preterm and term infants. Multiple searches using PubMed were conducted including the search terms "infant skin care," "infant products," "infant bath," "emollients," "diaper skin care," and "diaper wipes." Reference lists of comprehensive reviews were also scanned. Google searches were used to assess consumer information, product information, and regulatory guidelines. There is little scientific evidence to support safety of natural/organic products on infant skin. Raw materials originate from different sources, complicating testing and comparisons of ingredients. Research shows that cleansers formulated for infant skin do not weaken the skin barrier the way harsher soaps and detergents can. Oils with the lowest oleic acid content provide a lower risk of irritant contact dermatitis. Nurses must be informed about natural and organic products, preservatives, and fragrances and know the definition of commonly used marketing terms. Decisions regarding the use of infant products in preterm and term infants should be evidence based. More research is needed to support claims regarding the safety of products used on infant skin.

  14. Quercitrin protects skin from UVB-induced oxidative damage.

    PubMed

    Yin, Yuanqin; Li, Wenqi; Son, Young-Ok; Sun, Lijuan; Lu, Jian; Kim, Donghern; Wang, Xin; Yao, Hua; Wang, Lei; Pratheeshkumar, Poyil; Hitron, Andrew J; Luo, Jia; Gao, Ning; Shi, Xianglin; Zhang, Zhuo

    2013-06-01

    Exposure of the skin to ultraviolet B (UVB) radiation causes oxidative damage to skin, resulting in sunburn, photoaging, and skin cancer. It is generally believed that the skin damage induced by UV irradiation is a consequence of generation of reactive oxygen species (ROS). Recently, there is an increased interest in the use of natural products as chemopreventive agents for non-melanoma skin cancer (NMSC) due to their antioxidants and anti-inflammatory properties. Quercitrin, glycosylated form of quercetin, is the most common flavonoid in nature with antioxidant properties. The present study investigated the possible beneficial effects of quercitrin to inhibit UVB irradiation-induced oxidative damage in vitro and in vivo. Our results showed that quercitrin decreased ROS generation induced by UVB irradiation in JB6 cells. Quercitrin restored catalase expression and GSH/GSSG ratio reduced by UVB exposure, two major antioxidant enzymes, leading to reductions of oxidative DNA damage and apoptosis and protection of the skin from inflammation caused by UVB exposure. The present study demonstrated that quercitrin functions as an antioxidant against UVB irradiation-induced oxidative damage to skin. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Jasmine rice panicle: A safe and efficient natural ingredient for skin aging treatments.

    PubMed

    Kanlayavattanakul, Mayuree; Lourith, Nattaya; Chaikul, Puxvadee

    2016-12-04

    While rice is one of the most important global staple food sources its extracts have found many uses as the bases of herbal remedies. Rice extracts contain high levels of phenolic compounds which are known to be bioactive, some of which show cutaneous benefits and activity towards skin disorders. This study highlights an assessment of the cellular activity and clinical efficacy of rice panicle extract, providing necessary information relevant to the development of new cosmetic products. Jasmine rice panicle extract was standardized, and the level of phenolics present was determined. In vitro anti-aging, and extract activity towards melanogenesis was conducted in B16F10 melanoma cells, and antioxidant activity was assessed in human skin fibroblast cell cultures. Topical product creams containing the extract were developed, and skin irritation testing using a single application closed patch test method was done using 20 Thai volunteers. Randomized double-blind, placebo-controlled efficacy evaluation was undertaken in 24 volunteers over an 84d period, with the results monitored by Corneometer ® CM 825, Cutometer ® MPA 580, Mexameter ® MX 18 and Visioscan ® VC 98. Jasmine rice panicle extract was shown to have a high content of p-coumaric, ferulic and caffeic acids, and was not cytotoxic to the cell lines used in this study. Cells treated with extract suppressed melanogenesis via tyrosinase and TRP-2 inhibitory effects, which protect the cell from oxidative stress at doses of 0.1mg/ml or lower. The jasmine rice panicle preparations (0.1-0.2%) were safe (MII=0), and significantly (p<0.05) increased skin hydration levels relative to baseline. Skin lightening, and anti-wrinkle effects related to skin firmness and smoothness were observed, in addition to a reduction in skin wrinkling. Improvements in skin biophysics of both 0.1% and 0.2% extracts were showed to be comparable (p>0.05). Jasmine rice panicle extract having high levels of phenolics shows cutaneous benefits

  16. Plants used to treat skin diseases

    PubMed Central

    Tabassum, Nahida; Hamdani, Mariya

    2014-01-01

    Skin diseases are numerous and a frequently occurring health problem affecting all ages from the neonates to the elderly and cause harm in number of ways. Maintaining healthy skin is important for a healthy body. Many people may develop skin diseases that affect the skin, including cancer, herpes and cellulitis. Some wild plants and their parts are frequently used to treat these diseases. The use of plants is as old as the mankind. Natural treatment is cheap and claimed to be safe. It is also suitable raw material for production of new synthetic agents. A review of some plants for the treatment of skin diseases is provided that summarizes the recent technical advancements that have taken place in this area during the past 17 years. PMID:24600196

  17. Prunus mume extract exerts antioxidant activities and suppressive effect of melanogenesis under the stimulation by alpha-melanocyte stimulating hormone in B16-F10 melanoma cells.

    PubMed

    Pi, KyungBae; Lee, KiBeom

    2017-10-01

    In the current study, we examined the antioxidant and skin-whitening properties of Prunus mume extract (PME). The ability of PME to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals was investigated in vitro. At a concentration of 1000 μg/mL, PME neutralized >45% free radical activity. Cell viability assessment with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay revealed that at concentrations <1500 μg/mL, PME does not exert cytotoxic effects on murine B16 melanoma (B16) cells. Morphological analysis disclosed that melanin production is inhibited in B16 cells treated with 250 nM α-melanocyte-stimulating hormone (α-MSH) and PME. We conclude that fruit extracts of P. mume exert a skin-whitening effect by inhibiting melanin production via regulation of melanogenesis-associated protein expression in melanocytes.

  18. Influence of in-office whitening gel pH on hydrogen peroxide diffusion through enamel and color changes in bovine teeth.

    PubMed

    Pignoly, Christian; Camps, Lila; Susini, Guy; About, Imad; Camps, Jean

    2012-04-01

    To assess the influence of in-office whitening gel pH on whitening efficiency. Hydrogen peroxide diffusion and color changes on bovine teeth were assessed. Three gels with close hydrogen peroxide concentrations but with various pH levels were tested: Zoom 2 (Discus Dental), Opalescence Endo and Opalescence Boost (Ultradent). The pH levels were respectively: 3.0, 5.0 and 7.0. Thirty enamel slices and tooth crowns were used for both studies (n = 10 per group per study). Hydrogen peroxide diffusion through the enamel slices and the tooth crowns was spectrophotometrically recorded every 10 minutes for 1 hour to calculate the diffusion coefficients. Color changes were spectrophotometrically recorded every 10 minutes for 1 hour and quantified in term of CIE-Lab. The hydrogen peroxide diffusion coefficient through enamel ranged from 5.12 +/- 0.82 x 10(-9) cm2 s(-1) for pH 3 to 5.19 +/- 0.92 x 10(-9) cm2 S(-1) for pH 7. Through tooth crowns it ranged from 4.80 +/- 1.75 x 10(-10) cm2 s(-1) for pH 5 to 4.85 +/- 1.82 x 10(-10) cm2 s(-1) for pH 3. After 1 hour, the deltaE varied from 5.6 +/- 4.0 for pH 7 to 7.0 +/- 5.0 for pH 3 on enamel slices and from 3.9 +/- 2.5 for pH 5 to 4.9 +/- 3.5 for pH 7 on tooth crowns. There was no statistically significant difference between groups for both parameters.

  19. Effect of four different opalescence tooth-whitening products on enamel microhardness.

    PubMed

    Majeed, A; Grobler, S R; Moola, M H; Rossouw, R J; van Kotze, T J W

    2008-06-01

    The purpose was to evaluate the effect of various Opalescence tooth-whitening products on enamel. Enamel blocks were exposed to Opalescence PF 10% Carbamide Peroxide (n = 10), Opalescence PF 20% Carbamide Peroxide (n = 10), Opalescence Trèswhite Supreme 10% Hydrogen Peroxide (n = 10) and Opalescence Quick PF 45% Carbamide Peroxide (n = 10) according to the manufacturer's instructions. The control group was enamel blocks (n = 10) kept in artificial saliva. The values were obtained before exposure and after the 14-days treatment period. Enamel blocks were kept in saliva between treatments. Indent marks on enamel blocks were examined using the scanning electron microscope for treatment effects. All four different Opalescence products damaged enamel. The most damage was done when treated for a long period (112 hours). SEM images also showed damage to enamel by all 4 products. Opalescence with 10% and with 20% Carbamide Peroxide showed the highest damage, which also differed significantly (p < 0.05) from the saliva control group (p < 0.05; Tukey-Kramer Multiple comparison test). All 4 Opalescence products damaged enamel. Higher damage was done by the 10% carbamide peroxide and 20% carbamide peroxide products because of the much longer exposure period (112 hours in comparison to 7 hours).

  20. Advances in skin regeneration: application of electrospun scaffolds.

    PubMed

    Norouzi, Mohammad; Boroujeni, Samaneh Moghadasi; Omidvarkordshouli, Noushin; Soleimani, Masoud

    2015-06-03

    The paucity of cellular and molecular signals essential for normal wound healing makes severe dermatological ulcers stubborn to heal. The novel strategies of skin regenerative treatments are focused on the development of biologically responsive scaffolds accompanied by cells and multiple biomolecules resembling structural and biochemical cues of the natural extracellular matrix (ECM). Electrospun nanofibrous scaffolds provide similar architecture to the ECM leading to enhancement of cell adhesion, proliferation, migration and neo tissue formation. This Review surveys the application of biocompatible natural, synthetic and composite polymers to fabricate electrospun scaffolds as skin substitutes and wound dressings. Furthermore, the application of biomolecules and therapeutic agents in the nanofibrous scaffolds viz growth factors, genes, antibiotics, silver nanoparticles, and natural medicines with the aim of ameliorating cellular behavior, wound healing, and skin regeneration are discussed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Cutaneous leishmaniosis in naturally infected dogs in Paraná, Brazil, and the epidemiological implications of Leishmania (Viannia) braziliensis detection in internal organs and intact skin.

    PubMed

    Marquez, Ellen de Souza; de Castro, Edilene Alcântara; Nabut, Luciene Biazono; da Costa-Ribeiro, Magda Clara Vieira; Dela Coletta Troiano Araújo, Ludmilla; Poubel, Saloe Bispo; Gonçalves, André Luiz; Cruz, Mariza Fordellone Rosa; Dos Santos Trad, Ana Paula Millet Evangelista; Dias, Rafael Andre Ferreira; Navarro, Italmar Teodorico; Thomaz-Soccol, Vanete

    2017-08-30

    Environmental changes have occurred over the years, altering the eco-epidemiological pattern of leishmaniosis in the State of Paraná, Brazil, involving the pillars of the cycle (parasite, vectors, reservoir, and environment) and their interaction. Much has been discussed about the dog's role as a reservoir of the Leishmania (Viannia) braziliensis Vianna, 1911 transmission cycle. However, this question remains unanswered. The purpose of this study was to investigate, using parasitological and molecular methods, different samples in eight naturally infected dogs from an endemic rural locality where only L. (V.) braziliensis is present, and where human cases have been previously notified. Blood and biopsied organ samples from naturally infected dogs were analyzed by culture media, PCR, random amplified polymorphic DNA and sequencing methodologies. Only skin lesions from all dogs yielded positive cultures and when PCR was performed, L. (V.) braziliensis DNA was amplified from intact skin, peripheral blood, bone marrow, spleen, liver and lymph nodes. RAPD was also applied to isolates from the skin lesions, exhibiting the genetic variability of the parasite identified. To confirm which species of Leishmania was amplified in PCR, the sequencing method was performed, verifying 100% similarity with the Viannia subgenus. This study showed that L. (V.) braziliensis can spread to other sites besides the ulcerous lesions, such as intact skin, peripheral blood and internal organs, making it possibility for dogs to serve as active sources of parasite transmission. For definitive proof, xenodiagnostic test on intact skin of infected dogs, should be done. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Comparative studies on the chemical and enzymatic stability of alpa-and beta-arbutin

    USDA-ARS?s Scientific Manuscript database

    Alpha and beta arbutin are glycoside derivatives used as skin whitening agents. Both compounds interfere with tyrosinases activity in a fashion similar to their aglycone hydroquinone. Hydroquinone has been associated with ochronosis and possible carcinogenic effect. Due to their structural similarit...

  3. Advances in Skin Regeneration Using Tissue Engineering.

    PubMed

    Vig, Komal; Chaudhari, Atul; Tripathi, Shweta; Dixit, Saurabh; Sahu, Rajnish; Pillai, Shreekumar; Dennis, Vida A; Singh, Shree R

    2017-04-07

    Tissue engineered skin substitutes for wound healing have evolved tremendously over the last couple of years. New advances have been made toward developing skin substitutes made up of artificial and natural materials. Engineered skin substitutes are developed from acellular materials or can be synthesized from autologous, allograft, xenogenic, or synthetic sources. Each of these engineered skin substitutes has their advantages and disadvantages. However, to this date, a complete functional skin substitute is not available, and research is continuing to develop a competent full thickness skin substitute product that can vascularize rapidly. There is also a need to redesign the currently available substitutes to make them user friendly, commercially affordable, and viable with longer shelf life. The present review focuses on providing an overview of advances in the field of tissue engineered skin substitute development, the availability of various types, and their application.

  4. [Compression treatment for burned skin].

    PubMed

    Jaafar, Fadhel; Lassoued, Mohamed A; Sahnoun, Mahdi; Sfar, Souad; Cheikhrouhou, Morched

    2012-02-01

    The regularity of a compressive knit is defined as its ability to perform its function in a burnt skin. This property is essential to avoid the phenomenon of rejection of the material or toxicity problems But: Make knits biocompatible with high burnet of human skin. We fabric knits of elastic material. To ensure good adhesion to the skin, we made elastic material, typically a tight loop knitted. The Length of yarn absorbed by stitch and the raw matter are changed with each sample. The physical properties of each sample are measured and compared. Surface modifications are made to these samples by impregnation of microcapsules based on jojoba oil. Knits are compressif, elastic in all directions, light, thin, comfortable, and washable for hygiene issues. In addition, the washing can find their compressive properties. The Jojoba Oil microcapsules hydrated the human burnet skin. This moisturizer is used to the firmness of the wound and it gives flexibility to the skin. Compressive Knits are biocompatible with burnet skin. The mixture of natural and synthetic fibers is irreplaceable in terms comfort and regularity.

  5. Sebum and Hydration Levels in Specific Regions of Human Face Significantly Predict the Nature and Diversity of Facial Skin Microbiome.

    PubMed

    Mukherjee, Souvik; Mitra, Rupak; Maitra, Arindam; Gupta, Satyaranjan; Kumaran, Srikala; Chakrabortty, Amit; Majumder, Partha P

    2016-10-27

    The skin microbiome varies across individuals. The causes of these variations are inadequately understood. We tested the hypothesis that inter-individual variation in facial skin microbiome can be significantly explained by variation in sebum and hydration levels in specific facial regions of humans. We measured sebum and hydration from forehead and cheek regions of healthy female volunteers (n = 30). Metagenomic DNA from skin swabs were sequenced for V3-V5 regions of 16S rRNA gene. Altogether, 34 phyla were identified; predominantly Actinobacteria (66.3%), Firmicutes (17.7%), Proteobacteria (13.1%) and Bacteroidetes (1.4%). About 1000 genera were identified; predominantly Propionibacterium (58.6%), Staphylococcus (8.6%), Streptococcus (4.0%), Corynebacterium (3.6%) and Paracoccus (3.3%). A subset (n = 24) of individuals were sampled two months later. Stepwise multiple regression analysis showed that cheek sebum level was the most significant predictor of microbiome composition and diversity followed by forehead hydration level; forehead sebum and cheek hydration levels were not. With increase in cheek sebum, the prevalence of Actinobacteria (p = 0.001)/Propionibacterium (p = 0.002) increased, whereas microbiome diversity decreased (Shannon Index, p = 0.032); this was opposite for other phyla/genera. These trends were reversed for forehead hydration levels. Therefore, the nature and diversity of facial skin microbiome is jointly determined by site-specific lipid and water levels in the stratum corneum.

  6. Natural Arctium lappa fruit extract improves the clinical signs of aging skin.

    PubMed

    Knott, Anja; Reuschlein, Katja; Mielke, Heiko; Wensorra, Ursula; Mummert, Christopher; Koop, Urte; Kausch, Martina; Kolbe, Ludger; Peters, Nils; Stäb, Franz; Wenck, Horst; Gallinat, Stefan

    2008-12-01

    Subclinical, chronic tissue inflammation involving the generation of cytokines (e.g., interleukin-6 and tumor necrosis factor-alpha) might contribute to the cutaneous aging process. This study aims to screen for an active ingredient with anti-inflammatory (i.e., reduction of interleukin-6 and tumor necrosis factor-alpha) and matrix-stimulating efficacy which improves the clinical signs of skin aging in vivo. In vitro studies with pure Arctiin were performed investigating the inhibition of cytokine induction and stimulation of collagen neo-synthesis. In vivo home-in-use studies using an Arctium lappa fruit extract-containing formulation were carried out to determine procollagen and hyaluronan synthesis, hyaluronan synthase-2 gene expression, and reduction of wrinkle volume after treatment. In vitro studies on human dermal fibroblasts and monocyte-derived dendritic cells supplemented with pure Arctiin showed relative to untreated control cells a stimulation of collagen synthesis and a decrease in interleukin-6 and tumor necrosis factor-alpha concentration, respectively. In addition, topical in vivo application of an A. lappa fruit extract-containing formulation for 12 weeks significantly stimulated procollagen synthesis and increased hyaluronan synthase-2 expression as well as hyaluronan levels compared to vehicle-treated control areas. Similarly, after a 4-week treatment with an A. lappa fruit extract-containing formulation, wrinkle volume in the crow's feet area was significantly reduced as compared to treatment with the vehicle. Our data show that topical treatment with a natural A. lappa fruit extract significantly improves the metabolism of the dermal extracellular matrix and leads to a visible wrinkle reduction in vivo. In conclusion, A. lappa fruit extract represents a targeted means to regenerate dermal structures and, thus, offers an effective treatment option for mature skin.

  7. Biologically inspired multi-layered synthetic skin for tactile feedback in prosthetic limbs.

    PubMed

    Osborn, Luke; Nguyen, Harrison; Betthauser, Joseph; Kaliki, Rahul; Thakor, Nitish

    2016-08-01

    The human body offers a template for many state-of-the-art prosthetic devices and sensors. In this work, we present a novel, sensorized synthetic skin that mimics the natural multi-layered nature of mechanoreceptors found in healthy glabrous skin to provide tactile information. The multi-layered sensor is made up of flexible piezoresistive textiles that act as force sensitive resistors (FSRs) to convey tactile information, which are embedded within a silicone rubber to resemble the compliant nature of human skin. The top layer of the synthetic skin is capable of detecting small loads less than 5 N whereas the bottom sensing layer responds reliably to loads over 7 N. Finite element analysis (FEA) of a simplified human fingertip and the synthetic skin was performed. Results suggest similarities in behavior during loading. A natural tactile event is simulated by loading the synthetic skin on a prosthetic limb. Results show the sensors' ability to detect applied loads as well as the ability to simulate neural spiking activity based on the derivative and temporal differences of the sensor response. During the tactile loading, the top sensing layer responded 0.24 s faster than the bottom sensing layer. A synthetic biologically-inspired skin such as this will be useful for enhancing the functionality of prosthetic limbs through tactile feedback.

  8. Thai plants with high antioxidant levels, free radical scavenging activity, anti-tyrosinase and anti-collagenase activity.

    PubMed

    Chatatikun, Moragot; Chiabchalard, Anchalee

    2017-11-09

    Ultraviolet radiation from sunlight induces overproduction of reactive oxygen species (ROS) resulting in skin photoaging and hyperpigmentation disorders. Novel whitening and anti-wrinkle compounds from natural products have recently become of increasing interest. The purpose of this study was to find products that reduce ROS in 14 Thai plant extracts. To determine total phenolic and flavonoid content, antioxidant activity, anti-tyrosinase activity and anti-collagenase activity, we compared extracts of 14 Thai plants prepared using different solvents (petroleum ether, dichloromethane and ethanol). Antioxidant activities were determined by DPPH and ABTS assays. Total phenolic content of the 14 Thai plants extracts was found at the highest levels in ethanol followed by dichloromethane and petroleum ether extracts, respectively, while flavonoid content was normally found in the dichloromethane fraction. Scavenging activity ranged from 7 to 99% scavenging as assessed by DPPH and ABTS assays. The ethanol leaf extract of Ardisia elliptica Thunb. had the highest phenolic content, antioxidant activity and collagenase inhibition, while Cassia alata (L.) Roxb. extract had the richest flavonoid content. Interestingly, three plants extracts, which were the ethanolic fractions of Annona squamosa L., Ardisia elliptica Thunb. and Senna alata (L.) Roxb., had high antioxidant content and activity, and significantly inhibited both tyrosinase and collagenase. Our finding show that the ethanol fractions of Annona squamosa L., Ardisia elliptica Thunb. and Senna alata (L.) Roxb. show promise as potential ingredients for cosmetic products such as anti-wrinkle agents and skin whitening products.

  9. Quercitrin protects skin from UVB-induced oxidative damage

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yin, Yuanqin; Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY; Li, Wenqi

    Exposure of the skin to ultraviolet B (UVB) radiation causes oxidative damage to skin, resulting in sunburn, photoaging, and skin cancer. It is generally believed that the skin damage induced by UV irradiation is a consequence of generation of reactive oxygen species (ROS). Recently, there is an increased interest in the use of natural products as chemopreventive agents for non-melanoma skin cancer (NMSC) due to their antioxidants and anti-inflammatory properties. Quercitrin, glycosylated form of quercetin, is the most common flavonoid in nature with antioxidant properties. The present study investigated the possible beneficial effects of quercitrin to inhibit UVB irradiation-induced oxidativemore » damage in vitro and in vivo. Our results showed that quercitrin decreased ROS generation induced by UVB irradiation in JB6 cells. Quercitrin restored catalase expression and GSH/GSSG ratio reduced by UVB exposure, two major antioxidant enzymes, leading to reductions of oxidative DNA damage and apoptosis and protection of the skin from inflammation caused by UVB exposure. The present study demonstrated that quercitrin functions as an antioxidant against UVB irradiation-induced oxidative damage to skin. - Highlights: • Oxidative stress plays a key role in UV-induced cell and tissue injuries. • Quercitrin decreases ROS generation and restores antioxidants irradiated by UVB. • Quercitrin reduces UVB-irradiated oxidative DNA damage, apoptosis, and inflammation. • Quercitrin functions as an antioxidant against UVB-induced skin injuries.« less

  10. The nature and consequence of Karl Marx's skin disease.

    PubMed

    Shuster, S

    2008-01-01

    From an analysis of the original correspondence, it has been possible to establish that Karl Marx's incapacitating skin disease was hidradenitis suppurativa, not 'boils' as was universally assumed at the time and since; the psychological effect of this illness on the man and his work appears to have been considerable.

  11. Skin and Composite Grafting Techniques in Facial Reconstruction for Skin Cancer.

    PubMed

    Brenner, Michael J; Moyer, Jeffrey S

    2017-08-01

    Skin and composite grafting provide effective resurfacing and reconstruction for cutaneous defects after excision of the malignancy. The goal is to restore a natural appearance and function while preventing distortion of the eyelid, nose, or lips. With careful planning and attention to aesthetic subunits, the surgeon can camouflage incisions and avoid blunting aesthetically sensitive sulci. The surgical plan is also informed by the pathology, as basal or squamous cell carcinomas removed by Mohs micrographic excision have different prognostic and logistical considerations from melanoma. Skin and composite grafting are useful as stand-alone procedures or may complement local flaps and other soft tissue reconstructions. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Delayed manifestation of bilateral scleral thinning after I-BRITE® procedure and review of literature for cosmetic eye-whitening procedures

    PubMed Central

    Moshirfar, Majid; McCaughey, Michael V; Fenzl, Carlton R; Santiago-Caban, Luis; Kramer, Gregory D; Mamalis, Nick

    2015-01-01

    Purpose To report a case of delayed-onset bilateral scleral thinning and calcium deposition following a cosmetic ocular-whitening procedure (I-BRITE®). Methods A 33-year-old male patient with a history of right-sided ptosis repair and left-sided anterior uveitis had previously undergone bilateral I-BRITE treatment for chronic conjunctival hyperemia. Four years after the procedure, the patient was referred to our institution with bilateral scleral thinning and overlying calcific depositions. A literature review was performed through PubMed from 1980 through 2014 using the search terms ‘cosmetic’, ‘ocular’, ‘conjunctivectomy’, ‘regional conjunctivectomy’, ‘I-BRITE’, ‘eye-whitening’, ‘scleritis’, ‘necrotizing scleritis’, ‘anterior uveitis’, ‘mitomycin C’, ‘5-fluorouracil’, and ‘bevacizumab’, along with associated cross-referencing from relevant articles. Results Examination of the patient revealed bilateral necrotizing scleritis within the nasal region of both eyes. Calcified plaques were also present within the areas of scleromalacia, along with epithelial defects demonstrated with fluorescein staining. Although evidence of previous intraocular inflammation was apparent within the left eye, there were no active signs of inflammation evident within either eye on initial presentation. Complication rates reported in the literature include: scleral thinning (1.8%), calcific plaque formation (2.9%), fibrovascular proliferation (13%), diplopia (1.2%), elevation of intraocular pressure (4.2%), and recurrence of conjunctival hyperemia (2.1%). Conclusion Cosmetic ocular whitening procedures have an attendant high complication rate, and have been associated with several adverse postoperative complications, which have in turn generated several reservations regarding the veritable benefit of the procedure. Many postsurgical complications may demonstrate delayed apparition, varying from several months to several years after primary

  13. Opportunities for Skin Cancer Prevention Education among Individuals Attending a Community Skin Cancer Screening in a High-Risk Catchment Area.

    PubMed

    Parsons, Bridget Grahmann; Gren, Lisa H; Simonsen, Sara E; Harding, Garrett; Grossman, Douglas; Wu, Yelena P

    2018-04-01

    Despite the highly preventable nature of skin cancer, it remains the most commonly diagnosed form of cancer in the United States. Recommendations for a complete skin cancer prevention regimen include engaging in photoprotection (e.g., sunscreen use), avoiding skin cancer risk behaviors (e.g., tanning), and receiving total body skin exams from a health care provider. The current study examined reported engagement in these behaviors among participants attending a community skin cancer screening (N = 319) in a high-risk catchment area to assess the need for increased health education on skin cancer prevention. Participants' responses indicate a history of suboptimal avoidance of skin cancer risk behaviors. Over half of participants (52%) reported four or more blistering sunburns before age 20, and 46% reported indoor tanning at least one during their lifetime. There is a need among this population for education regarding a complete skin cancer prevention regimen, which could improve adherence to photoprotection and avoidance of skin cancer risk behaviors, thereby reducing morbidity and mortality due to skin cancer.

  14. Effect of olive and sunflower seed oil on the adult skin barrier: implications for neonatal skin care.

    PubMed

    Danby, Simon G; AlEnezi, Tareq; Sultan, Amani; Lavender, Tina; Chittock, John; Brown, Kirsty; Cork, Michael J

    2013-01-01

    Natural oils are advocated and used throughout the world as part of neonatal skin care, but there is an absence of evidence to support this practice. The goal of the current study was to ascertain the effect of olive oil and sunflower seed oil on the biophysical properties of the skin. Nineteen adult volunteers with and without a history of atopic dermatitis were recruited into two randomized forearm-controlled mechanistic studies. The first cohort applied six drops of olive oil to one forearm twice daily for 5 weeks. The second cohort applied six drops of olive oil to one forearm and six drops of sunflower seed oil to the other twice daily for 4 weeks. The effect of the treatments was evaluated by determining stratum corneum integrity and cohesion, intercorneocyte cohesion, moisturization, skin-surface pH, and erythema. Topical application of olive oil for 4 weeks caused a significant reduction in stratum corneum integrity and induced mild erythema in volunteers with and without a history of atopic dermatitis. Sunflower seed oil preserved stratum corneum integrity, did not cause erythema, and improved hydration in the same volunteers. In contrast to sunflower seed oil, topical treatment with olive oil significantly damages the skin barrier, and therefore has the potential to promote the development of, and exacerbate existing, atopic dermatitis. The use of olive oil for the treatment of dry skin and infant massage should therefore be discouraged. These findings challenge the unfounded belief that all natural oils are beneficial for the skin and highlight the need for further research. © 2012 Wiley Periodicals, Inc.

  15. The chemistry of poisons in amphibian skin.

    PubMed Central

    Daly, J W

    1995-01-01

    Poisons are common in nature, where they often serve the organism in chemical defense. Such poisons either are produced de novo or are sequestered from dietary sources or symbiotic organisms. Among vertebrates, amphibians are notable for the wide range of noxious agents that are contained in granular skin glands. These compounds include amines, peptides, proteins, steroids, and both water-soluble and lipid-soluble alkaloids. With the exception of the alkaloids, most seem to be produced de novo by the amphibian. The skin of amphibians contains many structural classes of alkaloids previously unknown in nature. These include the batrachotoxins, which have recently been discovered to also occur in skin and feathers of a bird, the histrionicotoxins, the gephyrotoxins, the decahydroquinolines, the pumiliotoxins and homopumiliotoxins, epibatidine, and the samandarines. Some amphibian skin alkaloids are clearly sequestered from the diet, which consists mainly of small arthropods. These include pyrrolizidine and indolizidine alkaloids from ants, tricyclic coccinellines from beetles, and pyrrolizidine oximes, presumably from millipedes. The sources of other alkaloids in amphibian skin, including the batrachotoxins, the decahydroquinolines, the histrionicotoxins, the pumiliotoxins, and epibatidine, are unknown. While it is possible that these are produced de novo or by symbiotic microorganisms, it appears more likely that they are sequestered by the amphibians from as yet unknown dietary sources. PMID:7816854

  16. Two-stage damage diagnosis based on the distance between ARMA models and pre-whitening filters

    NASA Astrophysics Data System (ADS)

    Zheng, H.; Mita, A.

    2007-10-01

    This paper presents a two-stage damage diagnosis strategy for damage detection and localization. Auto-regressive moving-average (ARMA) models are fitted to time series of vibration signals recorded by sensors. In the first stage, a novel damage indicator, which is defined as the distance between ARMA models, is applied to damage detection. This stage can determine the existence of damage in the structure. Such an algorithm uses output only and does not require operator intervention. Therefore it can be embedded in the sensor board of a monitoring network. In the second stage, a pre-whitening filter is used to minimize the cross-correlation of multiple excitations. With this technique, the damage indicator can further identify the damage location and severity when the damage has been detected in the first stage. The proposed methodology is tested using simulation and experimental data. The analysis results clearly illustrate the feasibility of the proposed two-stage damage diagnosis methodology.

  17. Skin cancer chemoprevention by α-santalol.

    PubMed

    Zhang, Xiaoying; Dwivedi, Chandradhar

    2011-01-01

    Alpha-santalol, a naturally occurring terpenoid, has been shown to have chemopreventive effects on both 7, 12-dimethylbenz(a)anthracene (DMBA)-initiated and 12-O- tetradecanoylphorbol-13-acetate (TPA)-promoted skin cancer development in CD-1 and SENCAR mice, and UVB-induced skin cancer developments in SKH-1 hairless mice in a concentration-dependent manner. Studies have demonstrated that α-santalol could be effective against skin carcinogenesis through both induction of apoptosis via caspase activation together with dissipation of mitochondria membrane potential and cytochrome c release in A431 cells, and inhibition of cell growth via induction of G2/M phase arrest in both A431 cells and melanoma UACC-62 cells by altering multiple cell cycle regulatory proteins and complexes. This review summarizes the chemopreventive effects and molecular mechanisms of α-santalol on skin cancer development in both animal models and skin cancer cell lines.

  18. Efficacy of a 2% climbazole shampoo for reducing Malassezia population sizes on the skin of naturally infected dogs.

    PubMed

    Cavana, P; Petit, J-Y; Perrot, S; Guechi, R; Marignac, G; Reynaud, K; Guillot, J

    2015-12-01

    Shampoo therapy is often recommended for the control of Malassezia overgrowth in dogs. The aim of this study was to evaluate the in vivo activity of a 2% climbazole shampoo against Malassezia pachydermatis yeasts in naturally infected dogs. Eleven research colony Beagles were used. The dogs were distributed randomly into two groups: group A (n=6) and group B (n=5). Group A dogs were washed with a 2% climbazole shampoo, while group B dogs were treated with a physiological shampoo base. The shampoos were applied once weekly for two weeks. The population size of Malassezia yeasts on skin was determined by fungal culture through modified Dixon's medium contact plates pressed on left concave pinna, axillae, groins, perianal area before and after shampoo application. Samples collected were compared by Wilcoxon rank sum test. Samples collected after 2% climbazole shampoo application showed a significant and rapid reduction of Malassezia population sizes. One hour after the first climbazole shampoo application, Malassezia reduction was already statistically significant and 15 days after the second climbazole shampoo, Malassezia population sizes were still significantly decreased. No significant reduction of Malassezia population sizes was observed in group B dogs. The application of a 2% climbazole shampoo significantly reduced Malassezia population sizes on the skin of naturally infected dogs. Application of 2% climbazole shampoo may be useful for the control of Malassezia overgrowth and it may be also proposed as prevention when recurrences are frequent. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  19. Sebum and Hydration Levels in Specific Regions of Human Face Significantly Predict the Nature and Diversity of Facial Skin Microbiome

    PubMed Central

    Mukherjee, Souvik; Mitra, Rupak; Maitra, Arindam; Gupta, Satyaranjan; Kumaran, Srikala; Chakrabortty, Amit; Majumder, Partha P.

    2016-01-01

    The skin microbiome varies across individuals. The causes of these variations are inadequately understood. We tested the hypothesis that inter-individual variation in facial skin microbiome can be significantly explained by variation in sebum and hydration levels in specific facial regions of humans. We measured sebum and hydration from forehead and cheek regions of healthy female volunteers (n = 30). Metagenomic DNA from skin swabs were sequenced for V3-V5 regions of 16S rRNA gene. Altogether, 34 phyla were identified; predominantly Actinobacteria (66.3%), Firmicutes (17.7%), Proteobacteria (13.1%) and Bacteroidetes (1.4%). About 1000 genera were identified; predominantly Propionibacterium (58.6%), Staphylococcus (8.6%), Streptococcus (4.0%), Corynebacterium (3.6%) and Paracoccus (3.3%). A subset (n = 24) of individuals were sampled two months later. Stepwise multiple regression analysis showed that cheek sebum level was the most significant predictor of microbiome composition and diversity followed by forehead hydration level; forehead sebum and cheek hydration levels were not. With increase in cheek sebum, the prevalence of Actinobacteria (p = 0.001)/Propionibacterium (p = 0.002) increased, whereas microbiome diversity decreased (Shannon Index, p = 0.032); this was opposite for other phyla/genera. These trends were reversed for forehead hydration levels. Therefore, the nature and diversity of facial skin microbiome is jointly determined by site-specific lipid and water levels in the stratum corneum. PMID:27786295

  20. Simultaneous determination of water-soluble whitening ingredients and adenosine in different cosmetic formulations by high-performance liquid chromatography coupled with photodiode array detection.

    PubMed

    Jeon, J-S; Kim, H-T; Kim, M-G; Oh, M-S; Hong, S-R; Yoon, M-H; Cho, S-M; Shin, H-C; Shim, J-H; Ramadan, A; Abd El-Aty, A M

    2016-06-01

    The Korean Cosmetic Act regulates the use of functional cosmetics) by the law. Four functional cosmetic groups, whitening, anti-wrinkle, UV protection and combination of whitening and anti-wrinkle, were categorized according to the Korean Cosmetic Act and Functional Cosmetics Codex. In this study, high-performance liquid chromatography (HPLC) coupled with photodiode array detection (DAD) was employed for the simultaneous detection of arbutin (and its decomposition product, hydroquinone), niacinamide, ascorbyl glucoside, ethyl ascorbyl ether and adenosine in functional cosmetic products such as creams, emulsions and lotions. Separation by HPLC-DAD was conducted using a C18 column with a gradient elution of 5 mm KH2PO4 buffer (containing 0.1% phosphoric acid) and methanol (containing 0.1% phosphoric acid). The wavelengths for the detection of arbutin, hydroquinone, niacinamide, adenosine, ascorbyl glucoside and ethyl ascorbyl ether were 283, 289, 261, 257, 238 and 245 nm, respectively. This method exhibited good linearity (R(2) ≥ 0.999), precision (expressed as relative standard deviation (RSD) < 2%) and mean recoveries (89.42-104.89%). The results obtained by monitoring 100 market samples showed that the detected levels of the tested materials are within the acceptable authorized concentration. The method developed herein is simple and can be used for market survey and quality control of functional cosmetics. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  1. Scutellaria radix Extract as a Natural UV Protectant for Human Skin.

    PubMed

    Seok, Jin Kyung; Kwak, Jun Yup; Choi, Go Woon; An, Sang Mi; Kwak, Jae-Hoon; Seo, Hyeong-Ho; Suh, Hwa-Jin; Boo, Yong Chool

    2016-03-01

    Ultraviolet (UV) radiation induces oxidative injury and inflammation in human skin. Scutellaria radix (SR, the root of Scutellaria baicalensis Georgi) contains flavonoids with high UV absorptivity and antioxidant properties. The purpose of this study was to examine the potential use of SR extract as an additive in cosmetic products for UV protection. SR extract and its butanol (BuOH) fraction strongly absorbed UV radiation and displayed free radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl radials and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radicals. They also attenuated the UV-induced death of HaCaT cells. Sunscreen creams, with or without supplementation of SR extract BuOH fraction, were tested in vivo in human trials to evaluate potential skin irritation and determine the sun protection factor (SPF). Both sunscreen creams induced no skin irritation. A sunscreen cream containing 24% ZnO showed an SPF value of 17.8, and it increased to 22.7 when supplemented with 5% SR extract BuOH fraction. This study suggests that SR-derived materials are useful as safe cosmetic additives that provide UV protection. Copyright © 2015 John Wiley & Sons, Ltd.

  2. Sesamol-loaded solid lipid nanoparticles for treatment of skin cancer.

    PubMed

    Geetha, T; Kapila, Meenakshi; Prakash, Om; Deol, Parneet Kaur; Kakkar, Vandita; Kaur, Indu Pal

    2015-02-01

    Abstract Role of reactive oxygen species (ROS) in skin carcinogenesis is well documented. Natural molecules, like sesamol, with marked antioxidant potential can be useful in combating skin cancers. In vitro antiproliferative (using MTT assay) and DNA fragmentation studies in HL 60 cell lines, confirmed the apoptotic nature of sesamol. However, it showed a significant flux across the mice skin upon topical application, such that its local availability in skin is limited. Former is attributed mainly to its properties like small size, low molecular weight (138.28), and a sufficient lipid and water solubility (log P 1.29; solubility 38.8 mg/ml). To achieve its maximum epicutaneous delivery, packaging it into a suitable carrier system is thus indicated. Sesamol-loaded solid lipid nanoparticles (S-SLN) were thus prepared with particle size of 127.9 nm (PI: 0.256) and entrapment efficiency of 88.21%. Topical application of S-SLN in a cream base indicated significant retention in the skin with minimal flux across skin as confirmed by the in-vivo skin retention and ex-vivo skin permeation studies. In vivo anticancer studies performed on TPA-induced and benzo(a)pyrene initiated tumour production (ROS mediated) in mouse epidermis showed the normalization (in histology studies) of skin cancers post their induction, upon treatment with S-SLN.

  3. Skin acceptability of a cosmetic moisturizer formulation in female subjects with sensitive skin.

    PubMed

    Nisbet, Stephanie J

    2018-01-01

    This 3-week, open-label, noncomparative clinical study evaluated the skin acceptability of a cosmetic moisturizer in subjects with sensitive skin, by monitoring adverse events (AEs) and cutaneous discomfort related to normal usage. Female subjects aged between 18-60 years, with Fitzpatrick phototype classification I-IV and sensitive skin, verified by a positive reaction on the stinging test at screening, were included. Subjects applied the moisturizer to their face and body twice daily for 21±2 days at home and recorded study product usage and feelings of cutaneous discomfort (eg, dryness, prickling, stinging, and itching) in a diary; any AEs were reported to the clinic. At study end, skin acceptability of the moisturizer was investigator-assessed based on the nature of AEs and subjects' self-reported feelings of discomfort, and by clinical evaluation of skin reactions in the area of moisturizer application (appearance of erythema, formation of edema, and skin desquamation; scored according to an adapted Draize and Kligman scale). Only subjects with a treatment compliance of ≥80% were included in the final analysis. In total, 35 subjects initiated and completed the study; all were compliant to the minimum study product usage. Per investigator clinical dermatological assessment at study end, none of the 35 subjects had skin reactions in the area of moisturizer application and there were no reported AEs. One subject reported sensations of mild prickling and itching immediately after applying the moisturizer (not classified as AEs), which spontaneously remitted after complete absorption of the product and were noted only in exposed areas. These events were considered by the investigator as being possibly/probably related to the use of study product; however, no clinical signs of skin reaction were observed in the exposed areas. This cosmetic moisturizer appears generally well tolerated and suitable for topical use in subjects with sensitive skin.

  4. Febrile Illness with Skin Rashes

    PubMed Central

    2015-01-01

    Skin rashes that appear during febrile illnesses are in fact caused by various infectious diseases. Since infectious exanthematous diseases range from mild infections that disappear naturally to severe infectious diseases, focus on and basic knowledge of these diseases is very important. But, these include non-infectious diseases, so that comprehensive knowledge of these other diseases is required. Usually, early diagnostic testing for a febrile illness with a rash is inefficient. For clinical diagnosis of diseases accompanied by skin rash and fever, a complete history must be taken, including recent travel, contact with animals, medications, and exposure to forests and other natural environments. In addition, time of onset of symptoms and the characteristics of the rash itself (morphology, location, distribution) could be helpful in the clinical diagnosis. It is also critical to understand the patient's history of specific underlying diseases. However, diagnostic basic tests could be helpful in diagnosis if they are repeated and the clinical course is monitored. Generally, skin rashes are nonspecific and self-limited. Therefore, it could be clinically meaningful as a characteristic diagnostic finding in a very small subset of specific diseases. PMID:26483989

  5. Mechanics of a granular skin

    NASA Astrophysics Data System (ADS)

    Karmakar, Somnath; Sane, Anit; Bhattacharya, S.; Ghosh, Shankar

    2017-04-01

    Magic sand, a hydrophobic toy granular material, is widely used in popular science instructions because of its nonintuitive mechanical properties. A detailed study of the failure of an underwater column of magic sand shows that these properties can be traced to a single phenomenon: the system self-generates a cohesive skin that encapsulates the material inside. The skin, consisting of pinned air-water-grain interfaces, shows multiscale mechanical properties: they range from contact-line dynamics in the intragrain roughness scale, to plastic flow at the grain scale, all the way to sample-scale mechanical responses. With decreasing rigidity of the skin, the failure mode transforms from brittle to ductile (both of which are collective in nature) to a complete disintegration at the single-grain scale.

  6. Bad air gets under your skin.

    PubMed

    Koohgoli, Roxanna; Hudson, Laura; Naidoo, Khimara; Wilkinson, Simon; Chavan, Bhaven; Birch-Machin, Mark A

    2017-05-01

    Air pollution is increasing beyond previous estimates and is viewed as the world's largest environmental health risk factor. Numerous clinical and epidemiological studies have highlighted the adverse effects of environmental pollutants on health. Although there is comparatively less research investigating the cutaneous effects of ambient pollution, there is growing recognition of the adverse effects on skin. In this article, we provide an overview of the nature of environmental pollution and highlight the current evidence detailing the effects on cutaneous health. There is convincing evidence demonstrating that air pollution has a detrimental impact on skin and can exacerbate skin disease. Further epidemiological and experimental studies are required to assess the short- and long-term deleterious effects of ambient pollutant exposure on skin. The future challenge would be to use this evidence to develop specific strategies to protect against pollution-induced damage and prevent the effects of "bad air getting under our skin." © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Skin microbes on frogs prevent morbidity and mortality caused by a lethal skin fungus.

    PubMed

    Harris, Reid N; Brucker, Robert M; Walke, Jenifer B; Becker, Matthew H; Schwantes, Christian R; Flaherty, Devon C; Lam, Brianna A; Woodhams, Douglas C; Briggs, Cheryl J; Vredenburg, Vance T; Minbiole, Kevin P C

    2009-07-01

    Emerging infectious diseases threaten human and wildlife populations. Altered ecological interactions between mutualistic microbes and hosts can result in disease, but an understanding of interactions between host, microbes and disease-causing organisms may lead to management strategies to affect disease outcomes. Many amphibian species in relatively pristine habitats are experiencing dramatic population declines and extinctions due to the skin disease chytridiomycosis, which is caused by the chytrid fungus Batrachochytrium dendrobatidis. Using a randomized, replicated experiment, we show that adding an antifungal bacterial species, Janthinobacterium lividum, found on several species of amphibians to the skins of the frog Rana muscosa prevented morbidity and mortality caused by the pathogen. The bacterial species produces the anti-chytrid metabolite violacein, which was found in much higher concentrations on frog skins in the treatments where J. lividum was added. Our results show that cutaneous microbes are a part of amphibians' innate immune system, the microbial community structure on frog skins is a determinant of disease outcome and altering microbial interactions on frog skins can prevent a lethal disease outcome. A bioaugmentation strategy may be an effective management tool to control chytridiomycosis in amphibian survival assurance colonies and in nature.

  8. Effect of acidity of in-office bleaching gels on tooth sensitivity and whitening: a two-center double-blind randomized clinical trial.

    PubMed

    Loguercio, A D; Servat, F; Stanislawczuk, R; Mena-Serrano, A; Rezende, M; Prieto, M V; Cereño, V; Rojas, M F; Ortega, K; Fernandez, E; Reis, A

    2017-12-01

    The study aimed to compare the tooth sensitivity (TS) and bleaching efficacy of two hydrogen peroxide gels with different pHs (acid pH [Pola Office, SDI] and the neutral pH [Pola Office+, SDI]) used for in-office bleaching. Fifty-four patients from Brazil and Chile, with right superior incisor darker than A2, were selected for this double-blind, split-mouth randomized trial. Teeth were bleached in two sessions, with 1-week interval. Each session had three applications of 8 min each, according to the manufacturer's instructions. The color changes were evaluated by subjective (Vita Classical and Vita Bleachedguide) and objective (Easy shade spectrophotometer) methods. Participants recorded TS with 0-10 visual analog scale. Color change in shade guide units (SGU) and ΔE was analyzed by Student's t test (α = 0.05). The absolute risk and intensity of TS were evaluated by McNemar's test and Wilcoxon-paired test, respectively (α = 0.05). All groups achieved the same level of whitening after 30 days of clinical evaluation. The use of a neutral in-office bleaching gel significantly decreases the absolute risk of TS (28%, 95% CI 18-41) and intensity of TS when compared to the acid bleaching gel (absolute risk of 50%, 95% CI 37-63). The use of a neutral in-office bleaching agent gel produced the same whitening degree than an acid bleaching gel but with reduced risk and intensity of tooth sensitivity. Clinicians should opt to use in-office bleaching with a neutral gel than an acid product because the former causes a significant lower risk and intensity of tooth sensitivity.

  9. Prevention of lingual calculus formation with daily use of 6% H2O2/2% pyrophosphate whitening strips.

    PubMed

    Farrell, S; Barker, M L; Gerlach, R W; Putt, M S; Milleman, J L

    2009-01-01

    This randomized controlled clinical trial was conducted to evaluate whether daily use of a hydrogen peroxide/ pyrophosphate-containing antitartar whitening strip might safely yield clinical reductions in post-prophylaxis calculus accumulation. A three-month, randomized controlled trial was conducted to compare calculus accumulation with a daily 6% hydrogen peroxide/pyrophosphate strip versus regular brushing. After an eight-week run-in phase to identify calculus formers, a prophylaxis was administered, and 77 subjects were randomly assigned to daily strip or brushing only groups. All subjects received an anticavity dentifrice (Crest Cavity Protection) and manual brush for use throughout the three-month study; for subjects assigned to the experimental group, strip application was once daily for five minutes on the facial and lingual surfaces of the mandibular teeth. Efficacy was measured as mm calculus (VMI) before prophylaxis and after six and 12 weeks of treatment, while safety was assessed from examination and interview. Subjects ranged in age from 21-87 years, with groups balanced (p > 0.26) on pertinent demographic and behavioral parameters, and pre-prophylaxis calculus baseline mean scores (16.0 mm). At Week 6, calculus accumulation was lower in the strip group, with adjusted mean (SE) lingual VMI of 12.0 (0.87) for the strip group and 17.0 (0.88) for the brushing control. At Week 12, calculus accumulation was lower in the strip group, with adjusted mean (SE) lingual VMI of 14.3 (0.85) for the strip group and 17.2 (0.86) for the brushing control. Treatments differed significantly (p < 0.02) on calculus accumulation at both time points. A total of three subjects (8%) in the strip group and two subjects (5%) in the brushing control had mild oral irritation or tooth sensitivity during treatment; no one discontinued early due to an adverse event. Daily use of hydrogen peroxide whitening strips with pyrophosphate reduced calculus formation by up to 29% versus

  10. UV Radiation and the Skin

    PubMed Central

    D’Orazio, John; Jarrett, Stuart; Amaro-Ortiz, Alexandra; Scott, Timothy

    2013-01-01

    UV radiation (UV) is classified as a “complete carcinogen” because it is both a mutagen and a non-specific damaging agent and has properties of both a tumor initiator and a tumor promoter. In environmental abundance, UV is the most important modifiable risk factor for skin cancer and many other environmentally-influenced skin disorders. However, UV also benefits human health by mediating natural synthesis of vitamin D and endorphins in the skin, therefore UV has complex and mixed effects on human health. Nonetheless, excessive exposure to UV carries profound health risks, including atrophy, pigmentary changes, wrinkling and malignancy. UV is epidemiologically and molecularly linked to the three most common types of skin cancer, basal cell carcinoma, squamous cell carcinoma and malignant melanoma, which together affect more than a million Americans annually. Genetic factors also influence risk of UV-mediated skin disease. Polymorphisms of the melanocortin 1 receptor (MC1R) gene, in particular, correlate with fairness of skin, UV sensitivity, and enhanced cancer risk. We are interested in developing UV-protective approaches based on a detailed understanding of molecular events that occur after UV exposure, focusing particularly on epidermal melanization and the role of the MC1R in genome maintenance. PMID:23749111

  11. UV radiation and the skin.

    PubMed

    D'Orazio, John; Jarrett, Stuart; Amaro-Ortiz, Alexandra; Scott, Timothy

    2013-06-07

    UV radiation (UV) is classified as a "complete carcinogen" because it is both a mutagen and a non-specific damaging agent and has properties of both a tumor initiator and a tumor promoter. In environmental abundance, UV is the most important modifiable risk factor for skin cancer and many other environmentally-influenced skin disorders. However, UV also benefits human health by mediating natural synthesis of vitamin D and endorphins in the skin, therefore UV has complex and mixed effects on human health. Nonetheless, excessive exposure to UV carries profound health risks, including atrophy, pigmentary changes, wrinkling and malignancy. UV is epidemiologically and molecularly linked to the three most common types of skin cancer, basal cell carcinoma, squamous cell carcinoma and malignant melanoma, which together affect more than a million Americans annually. Genetic factors also influence risk of UV-mediated skin disease. Polymorphisms of the melanocortin 1 receptor (MC1R) gene, in particular, correlate with fairness of skin, UV sensitivity, and enhanced cancer risk. We are interested in developing UV-protective approaches based on a detailed understanding of molecular events that occur after UV exposure, focusing particularly on epidermal melanization and the role of the MC1R in genome maintenance.

  12. Human skin gene expression: Natural (trans) resveratrol versus five resveratrol analogs for dermal applications.

    PubMed

    Lephart, Edwin D; Andrus, Merritt B

    2017-09-01

    Resveratrol (RV) is a polyphenolic compound naturally produced by plants. Polyphenolic compounds incorporated into medicinal products are beneficial but, RV is rapidly metabolized with an associated decline in biological activity. This study tested RV as the standard and compared five structurally modified RV analogs: butyrate, isobutyrate, palmitoate, acetate, and diacetate (to improve functionality) at 1% concentration(s) for 24 h in epiderm full thickness cultures by gene array/qPCR mRNA analysis. When silent mating type information regulation 2 homolog 1, extracellular elements (collagen1A1, 3A1, 4A1; elastin, tissue inhibitor of matrix metalloproteinase 1, fibrillin 1 laminin beta1 and matrix metalloproteinase 9), anti-aging and aging genes, inflammatory biomarkers (interleukin-1A [IL1A], IL1R2, IL-6 and IL-8), nerve growth factor, and the antioxidants (proliferating cell nuclear antigen, catalase, superoxide dismutase and metallothionein 1H/2H) were evaluated, ranking each from highest-to-lowest for gene expression: butyrate > isobutyrate > diacetate > acetate > palmitoate. This study showed that the butyrate and isobutyrate analogs are more biologically active compared to resveratrol and have potential use in topical applications to improve dermal and other health applications. Impact statement Resveratrol has been reported to have a wide variety of health benefits but its rapid metabolism especially after oral ingestion results in very low bioavailability. Notably, the first human skin gene expression study of resveratrol was not published until 2014. The purpose of this study was to determine if increased stability and biological activity could be obtained by modifying the chemical structure of natural (trans) resveratrol and quantifying human gene expression by qPCR of skin biomarkers that enhance dermal health. Five resveratrol analogs were synthesized that increased their lipophilic index to enhance tissue penetration and augment

  13. Biologic and synthetic skin substitutes: An overview

    PubMed Central

    Halim, Ahmad Sukari; Khoo, Teng Lye; Mohd. Yussof, Shah Jumaat

    2010-01-01

    The current trend of burn wound care has shifted to more holistic approach of improvement in the long-term form and function of the healed burn wounds and quality of life. This has demanded the emergence of various skin substitutes in the management of acute burn injury as well as post burn reconstructions. Skin substitutes have important roles in the treatment of deep dermal and full thickness wounds of various aetiologies. At present, there is no ideal substitute in the market. Skin substitutes can be divided into two main classes, namely, biological and synthetic substitutes. The biological skin substitutes have a more intact extracellular matrix structure, while the synthetic skin substitutes can be synthesised on demand and can be modulated for specific purposes. Each class has its advantages and disadvantages. The biological skin substitutes may allow the construction of a more natural new dermis and allow excellent re-epithelialisation characteristics due to the presence of a basement membrane. Synthetic skin substitutes demonstrate the advantages of increase control over scaffold composition. The ultimate goal is to achieve an ideal skin substitute that provides an effective and scar-free wound healing. PMID:21321652

  14. Quantification of 4'-geranyloxyferulic acid, a new natural colon cancer chemopreventive agent, by HPLC-DAD in grapefruit skin extract.

    PubMed

    Genovese, S; Epifano, F; Carlucci, G; Marcotullio, M C; Curini, M; Locatelli, M

    2010-10-10

    Oxyprenylated natural products (isopentenyloxy-, geranyloxy- and the less spread farnesyloxy-compounds and their biosynthetic derivatives) represent a family of secondary metabolites that have been consider for years merely as biosynthetic intermediates of the most abundant C-prenylated derivatives. Many of the isolated oxyprenylated natural products were shown to exert in vitro and in vivo remarkable anti-cancer and anti-inflammatory effects. 4'-Geranyloxyferulic acid [3-(4'-geranyloxy-3'-methoxyphenyl)-2-trans-propenoic] has been discovered as a valuable chemopreventive agent of several types of cancer. After development of a high yield and "eco-friendly" synthetic scheme of this secondary metabolite, starting from cheap and non-toxic reagents and substrates, we developed a new HPLC-DAD method for its quantification in grapefruit skin extract. A preliminary study on C18 column showed the separation between GOFA and boropinic acid (having the same core but with an isopentenyloxy side chain), used as internal standard. The tested column were thermostated at 28+/-1 degrees C and the separation was achieved in gradient condition at a flow rate of 1 mL/min with a starting mobile phase of H(2)O:methanol (40:60, v/v, 1% formic acid). The limit of detection (LOD, S/N=3) was 0.5 microg/mL and the limit of quantification (LOQ, S/N=10) was 1 microg/mL. Matrix-matched standard curves showed linearity up to 75 microg/mL. In the analytical range the precision (RSD%) values were natural extract of grapefruit. In conclusion, this method showed LOQ values able to selective quantification of this analyte in grapefruit skin extract.

  15. Grey-Markov prediction model based on background value optimization and central-point triangular whitenization weight function

    NASA Astrophysics Data System (ADS)

    Ye, Jing; Dang, Yaoguo; Li, Bingjun

    2018-01-01

    Grey-Markov forecasting model is a combination of grey prediction model and Markov chain which show obvious optimization effects for data sequences with characteristics of non-stationary and volatility. However, the state division process in traditional Grey-Markov forecasting model is mostly based on subjective real numbers that immediately affects the accuracy of forecasting values. To seek the solution, this paper introduces the central-point triangular whitenization weight function in state division to calculate possibilities of research values in each state which reflect preference degrees in different states in an objective way. On the other hand, background value optimization is applied in the traditional grey model to generate better fitting data. By this means, the improved Grey-Markov forecasting model is built. Finally, taking the grain production in Henan Province as an example, it verifies this model's validity by comparing with GM(1,1) based on background value optimization and the traditional Grey-Markov forecasting model.

  16. The role of near infrared radiation in photoaging of the skin.

    PubMed

    Schroeder, Peter; Haendeler, Judith; Krutmann, Jean

    2008-07-01

    Infrared (IR) radiation is non-ionizing, electromagnetic radiation with wavelengths between 760 nm and 1 mm, which is further divided into IRA, IRB and IRC. IR accounts for more than half of the solar energy that reaches the human skin. While IRB and IRC do not penetrate deeply into the skin, more than 65% of IRA reaches the dermis. Human skin is increasingly exposed to IRA-radiation; most relevant sources are (i) natural solar radiation consisting of over 30% IRA, (ii) artificial IRA sources used for therapeutic or wellness purposes and (iii) artificial UV sources contaminated with IRA. As part of natural sunlight, IRA significantly contributes to extrinsic skin aging. This article reviews the cutaneous effects of IRA-radiation, the underlying molecular mechanisms and the available protective strategies.

  17. A supramolecular biomimetic skin combining a wide spectrum of mechanical properties and multiple sensory capabilities.

    PubMed

    Lei, Zhouyue; Wu, Peiyi

    2018-03-19

    Biomimetic skin-like materials, capable of adapting shapes to variable environments and sensing external stimuli, are of great significance in a wide range of applications, including artificial intelligence, soft robotics, and smart wearable devices. However, such highly sophisticated intelligence has been mainly found in natural creatures while rarely realized in artificial materials. Herein, we fabricate a type of biomimetic iontronics to imitate natural skins using supramolecular polyelectrolyte hydrogels. The dynamic viscoelastic networks provide the biomimetic skin with a wide spectrum of mechanical properties, including flexible reconfiguration ability, robust elasticity, extremely large stretchability, autonomous self-healability, and recyclability. Meanwhile, polyelectrolytes' ionic conductivity allows multiple sensory capabilities toward temperature, strain, and stress. This work provides not only insights into dynamic interactions and sensing mechanism of supramolecular iontronics, but may also promote the development of biomimetic skins with sophisticated intelligence similar to natural skins.

  18. Occupational Skin Hazards From Ultraviolet (UV) Exposures

    NASA Astrophysics Data System (ADS)

    Urbach, F.; Wolbarsht, M. L.

    1980-10-01

    The various types of UV effects on the skin are classified according to the part of the spectrum and their beneficial or deleterious nature. Some hazardous ultraviolet sources used in industrial processes are described, and examples of photoallergy, phototoxicity, and photosensitization resulting from UV exposures are given. The incidence of skin cancer as a function of geographical location and exposure to sunlight is discussed in relation to natural and artificial exposures to long and short wavelength UV, especially in connection with tanning booths. The conclusion is reached that there is enough ultraviolet in a normal environment to propose a hazard, and additional ultraviolet exposure from industrial or consumer sources is not necessary, and should be eliminated wherever possible.

  19. Occupational Skin Hazards From Ultraviolet (UV) Exposures

    NASA Astrophysics Data System (ADS)

    Urbach, F.; Wolbarsht, M. L.

    1981-11-01

    The various types of UV effects on the skin are classified according to the part of the spectrum and their beneficial or deleterious nature. Some hazardous ultraviolet sources used in industrial processes are described, and examples of photoallergy, phototoxicity, and photosensitization resulting from UV exposures are given. The incidence of skin cancer as a function of geographical location and exposure to sunlight is discussed in relation to natural and artificial exposures to long and short wavelength UV, especially in connection with tanning booths. The conclusion is reached that there is enough ultraviolet in a normal environment to propose a hazard, and additional ultraviolet exposure from industrial or consumer sources is not necessary, and should be eliminated wherever possible.

  20. Skin acceptability of a cosmetic moisturizer formulation in female subjects with sensitive skin

    PubMed Central

    Nisbet, Stephanie J

    2018-01-01

    Purpose This 3-week, open-label, noncomparative clinical study evaluated the skin acceptability of a cosmetic moisturizer in subjects with sensitive skin, by monitoring adverse events (AEs) and cutaneous discomfort related to normal usage. Materials and methods Female subjects aged between 18–60 years, with Fitzpatrick phototype classification I–IV and sensitive skin, verified by a positive reaction on the stinging test at screening, were included. Subjects applied the moisturizer to their face and body twice daily for 21±2 days at home and recorded study product usage and feelings of cutaneous discomfort (eg, dryness, prickling, stinging, and itching) in a diary; any AEs were reported to the clinic. At study end, skin acceptability of the moisturizer was investigator-assessed based on the nature of AEs and subjects’ self-reported feelings of discomfort, and by clinical evaluation of skin reactions in the area of moisturizer application (appearance of erythema, formation of edema, and skin desquamation; scored according to an adapted Draize and Kligman scale). Only subjects with a treatment compliance of ≥80% were included in the final analysis. Results In total, 35 subjects initiated and completed the study; all were compliant to the minimum study product usage. Per investigator clinical dermatological assessment at study end, none of the 35 subjects had skin reactions in the area of moisturizer application and there were no reported AEs. One subject reported sensations of mild prickling and itching immediately after applying the moisturizer (not classified as AEs), which spontaneously remitted after complete absorption of the product and were noted only in exposed areas. These events were considered by the investigator as being possibly/probably related to the use of study product; however, no clinical signs of skin reaction were observed in the exposed areas. Conclusion This cosmetic moisturizer appears generally well tolerated and suitable for topical

  1. An Adhesive Patch-Based Skin Biopsy Device for Molecular Diagnostics and Skin Microbiome Studies.

    PubMed

    Yao, Zuxu; Moy, Ronald; Allen, Talisha; Jansen, Burkhard

    2017-10-01

    A number of diagnoses in clinical dermatology are currently histopathologically confirmed and this image recognition-based confirmation generally requires surgical biopsies. The increasing ability of molecular pathology to corroborate or correct a clinical diagnosis based on objective gene expression, mutation analysis, or molecular microbiome data is on the horizon and would be further supported by a tool or procedure to collect samples non-invasively. This study characterizes such a tool in form of a 'bladeless' adhesive patch-based skin biopsy device. The performance of this device was evaluated through a variety of complementary technologies including assessment of sample biomass, electron microscopy demonstrating the harvesting of layers of epidermal tissue, and isolation of RNA and DNA from epidermal skin samples. Samples were obtained by application of adhesive patches to the anatomical area of interest. Biomass assessment demonstrated collection of approximately 0.3mg of skin tissue per adhesive patch and electron microscopy confirmed the nature of the harvested epidermal skin tissue. The obtained tissue samples are stored in a stable fashion on adhesive patches over a wide range of temperatures (-80oC to +60oC) and for extended periods of time (7 days or more). Total human RNA, human genomic DNA and microbiome DNA yields were 23.35 + 15.75ng, 27.72 + 20.71ng and 576.2 + 376.8pg, respectively, in skin samples obtained from combining 4 full patches collected non-invasively from the forehead of healthy volunteers. The adhesive patch skin sampling procedure is well tolerated and provides robust means to obtain skin tissue, RNA, DNA, and microbiome samples without involving surgical biopsies. The non-invasively obtained skin samples can be shipped cost effectively at ambient temperature by mail or standard courier service, and are suitable for a variety of molecular analyses of the skin microbiome as well as of keratinocytes, T cells, dendritic cells

  2. The skin microbiome: impact of modern environments on skin ecology, barrier integrity, and systemic immune programming.

    PubMed

    Prescott, Susan L; Larcombe, Danica-Lea; Logan, Alan C; West, Christina; Burks, Wesley; Caraballo, Luis; Levin, Michael; Etten, Eddie Van; Horwitz, Pierre; Kozyrskyj, Anita; Campbell, Dianne E

    2017-01-01

    Skin barrier structure and function is essential to human health. Hitherto unrecognized functions of epidermal keratinocytes show that the skin plays an important role in adapting whole-body physiology to changing environments, including the capacity to produce a wide variety of hormones, neurotransmitters and cytokine that can potentially influence whole-body states, and quite possibly, even emotions. Skin microbiota play an integral role in the maturation and homeostatic regulation of keratinocytes and host immune networks with systemic implications. As our primary interface with the external environment, the biodiversity of skin habitats is heavily influenced by the biodiversity of the ecosystems in which we reside. Thus, factors which alter the establishment and health of the skin microbiome have the potential to predispose to not only cutaneous disease, but also other inflammatory non-communicable diseases (NCDs). Indeed, disturbances of the stratum corneum have been noted in allergic diseases (eczema and food allergy), psoriasis, rosacea, acne vulgaris and with the skin aging process. The built environment, global biodiversity losses and declining nature relatedness are contributing to erosion of diversity at a micro-ecological level, including our own microbial habitats. This emphasises the importance of ecological perspectives in overcoming the factors that drive dysbiosis and the risk of inflammatory diseases across the life course.

  3. Comparing Alternative Methods of Measuring Skin Color and Damage

    PubMed Central

    Daniel, Lauren C.; Heckman, Carolyn J.; Kloss, Jacqueline D.; Manne, Sharon L.

    2009-01-01

    Objective: The current study investigated the reliability and validity of several skin color and damage measurement strategies and explored their applicability among participants of different races, skin types, and sexes. Methods: One hundred college-aged participants completed an online survey about their perceived skin damage and skin protection. They also attended an in-person session in which an observer rated their skin color; additionally, UV photos and spectrophotometry readings were taken. Results: Trained research assistants rated the damage depicted in the UV photos reliably. Moderate to high correlations emerged between skin color self-report and spectrophotometry readings. Observer rating correlated with spectrophotometry rating of current but not natural skin color. Lighter-skinned individuals reported more cumulative skin damage, which was supported by UV photography. Although women's current skin color was lighter and their UV photos showed similar damage to men's, women reported significantly more damaged skin than men did. Conclusions: These findings suggest that self-report continues to be a valuable measurement strategy when skin reflectance measurement is not feasible or appropriate and that UV photos and observer ratings may be useful but need to be tested further. The results also suggest that young women and men may benefit from different types of skin cancer prevention interventions. PMID:18931926

  4. Skin diseases during floods in Thailand.

    PubMed

    Vachiramon, Vasanop; Busaracome, Ploysyne; Chongtrakool, Piriyaporn; Puavilai, Siripen

    2008-04-01

    Floods are natural disasters that occur occasionally in Thailand. The most common form skin diseases due to floods are infectious dermatoses especially superficial fungal infection. However the microbiologic evidences have not been evaluated. To evaluate the most common skin diseases during floods and identify the organism that causes skin maceration at web space(s) of toes (Hong Kong foot). Patients who complained of skin problems were evaluated at the temporary outpatient clinic during October 2006. Skin specimens from all patients who had itches and skin maceration at web space(s) of toes were cultured. Ninety-six patients were evaluated (38 males and 58 females). Eczema was the most prevalent dermatosis, which accounted for 34.5% of the total skin problems and the great majority of these cases were irritant contact dermatitis. Sixteen cases presented with itch and skin maceration at web space(s) of toes. All of them were colonized with various microorganisms. Gram-negative bacilli were the most prevalent ones and were found in 14 out of 16 specimens. Fungal culture was positive in only two specimens. Eczema is the most common dermatosis during floods. Skin maceration at web space(s) of toes, which were thought to be fungal infection, are chronic irritant dermatitis with secondary bacterial colonization. Only a few cases were fungal infection. Microbiologic investigation should be done in these patients. Unfortunately, it is not practical in such a situation. Topical medications that have the combination of antiinflammatory, antibacterial and antifungal properties are the most suitable medications.

  5. Suitability of fluorescent whitening compounds (FWCs) as indicators of human faecal contamination from septic tanks in rural catchments.

    PubMed

    Dubber, Donata; Gill, Laurence W

    2017-12-15

    Rural river catchments are impacted by diffuse pollution sources from agricultural practices and on-site domestic wastewater treatment systems (DWWTS), mainly septic tanks. Methods that can distinguish between contamination sources will significantly increase water management efficiency as they will allow for the development and application of targeted remediation measures. Fluorescent whitening compounds (FWC), are used as optical brighteners in laundry detergents and enter the environment through the discharge of domestic wastewater effluents. Due to their human specific source and potential simple fluorometric measurement this represents a very attractive method to be used by state monitoring agencies. In this study the suitability of FWCs as chemical indicators for human faecal contamination has been investigated in rural Irish catchments. It was found that no quantitative measurements are possible for FWCs in natural waters when using simple fluorometric methods. Hence a simple presence/absence approach needs to be applied. The detectability of FWCs was quantified and found to decrease with higher organic matter content of the river water which has its own fluorescence. This enabled the establishment of equations to predict detection limits and assess the method's suitability for individual catchments based on organic matter concentrations. Furthermore a modified photodecay method is suggested that increases sensitivity of the technique by up to 59%. Applications at rural study sites found some removal of FWCs in percolation areas of DWWTSs but they were still detectable 40 cm below the infiltration depth. FWCs were also detected as distinguishable peaks in impacted streams where septic tank effluents have a high contribution to the river flow. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. 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.

  7. The Environment and the Microbial Ecology of Human Skin

    PubMed Central

    McBride, Mollie E.; Duncan, W. Christopher; Knox, J. M.

    1977-01-01

    Microbial flora of the skin of three human population groups representing different natural environments was examined quantitatively and qualitatively to determine whether environmental differences in temperature and humidity can influence the microbial flora of normal skin. Five anatomical skin sites - hands, back, axillae, groin, and feet - were sampled from 10 subjects working in a high-humidity, high-temperature environment, 10 subjects from a low-temperature, high-humidity environment, and 10 subjects working in a moderate-temperature and low-humidity environment. Bacterial populations were significantly larger from the back, axillae, and feet in individuals from the high-temperature and high-humidity environment as compared to the moderate-temperature, low-humidity environment. High humidity and low temperature had no significant effect on total populations, but this group showed a higher frequency of isolation of fungi, and gram-negative bacteria from the back and feet. Although there was an indication that increase in the environmental humidity could result in an increased frequency of isolation of gram-negative bacteria, there was no evidence that an increase in either temperature or humidity altered the relative proportions of gram-negative bacteria in the predominantly gram-positive microbial flora found on normal skin. It was concluded that, although climatic changes may cause fluctation in microbial populations from certain sites, they are not a major influence on the ecology of the microbial flora of normal skin in the natural environment. The variables introduced by studying individuals in their natural environment and the influence of these on the results are discussed. PMID:16345214

  8. Effect of Age on Tooth Shade, Skin Color and Skin-Tooth Color Interrelationship in Saudi Arabian Subpopulation.

    PubMed

    Haralur, Satheesh B

    2015-08-01

    Dental restoration or prosthesis in harmony with adjacent natural teeth color is indispensable part for the successful esthetic outcome. The studies indicate is existence of correlation between teeth and skin color. Teeth and skin color are changed over the aging process. The aim of the study was to explore the role of age on the tooth and skin color parameters, and to investigate the effect of ageing on teeth-skin color correlation. Total of 225 Saudi Arabian ethnic subjects was divided into three groups of 75 each. The groups were divided according to participant's age. The participant's age for Group I, Group II, and Group III was 18-29 years, 30-50 years, and above 50 years, respectively. The tooth color was identified by spectrophotometer in CIE Lab parameters. The skin color was registered with skin surface photography. The data were statistically analyzed with one-way ANOVA and correlation tests with SPSS 18 software. The Group I had the highest 'L' value of 80.26, Group III recorded the least value of 76.66. The Group III had highest yellow value 'b' at 22.72, while Group I had 19.19. The skin 'L' value was highest in the young population; the elder population had the increased red value 'a' in comparison to younger subjects. The 'L' tooth color parameter had a strong positive linear correlation with skin color in young and adult subjects. While Group III teeth showed the strong positive correlation with 'b' parameter at malar region. The elder subjects had darker and yellow teeth in comparison with younger subjects. The reddening of the skin was observed as age-related skin color change. The age had a strong influence on the teeth-skin color correlation.

  9. 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

  10. Skin Fungi from Colonization to Infection.

    PubMed

    de Hoog, Sybren; Monod, Michel; Dawson, Tom; Boekhout, Teun; Mayser, Peter; Gräser, Yvonne

    2017-07-01

    Humans are exceptional among vertebrates in that their living tissue is directly exposed to the outside world. In the absence of protective scales, feathers, or fur, the skin has to be highly effective in defending the organism against the gamut of opportunistic fungi surrounding us. Most (sub)cutaneous infections enter the body by implantation through the skin barrier. On intact skin, two types of fungal expansion are noted: (A) colonization by commensals, i.e., growth enabled by conditions prevailing on the skin surface without degradation of tissue, and (B) infection by superficial pathogens that assimilate epidermal keratin and interact with the cellular immune system. In a response-damage framework, all fungi are potentially able to cause disease, as a balance between their natural predilection and the immune status of the host. For this reason, we will not attribute a fixed ecological term to each species, but rather describe them as growing in a commensal state (A) or in a pathogenic state (B).

  11. Naturally acquired bovine besnoitiosis: Differential distribution of parasites in the skin of chronically infected cattle.

    PubMed

    Schares, G; Langenmayer, M C; Majzoub-Altweck, M; Scharr, J C; Gentile, A; Maksimov, A; Schares, S; Conraths, F J; Gollnick, N S

    2016-01-30

    Bovine besnoitiosis is caused by Besnoitia besnoiti, an apicomplexan parasite closely related to Toxoplasma gondii and Neospora caninum. In the acute stage of besnoitiosis, cattle suffer from pyrexia, swollen lymph nodes, anorexia and subcutaneous edema. In the chronic stage, tissue cysts are formed in a variety of tissues including the skin. Knowledge about the distribution of tissue cysts of different parts of the skin of infected animals is scarce. Four chronically infected cattle were euthanized and skin samples were taken from a total of 77 standardized cutaneous locations per animal. Portions of the dermis were taken, from which DNA was extracted and examined by real-time PCR. Cycle of transition (Ct) values reflecting the amount of parasite DNA in the samples were determined. For statistical analysis, samples were attributed to 11 larger skin regions ('OuterHindlegDistal', 'Rump, ForelegMiddle', 'NoseFrontEars', 'CheekEye', 'SideLowerPart', 'ForelegDistal', 'SideUpperPart', 'LegsInner', 'VentralHeadNeck', 'DorsalNeckWithersBackTail'). While all samples revealed a positive result in three female cattle, only 63.6% (49/77) of the samples of a bull showed positive results. For statistical analysis, a Ct value of 45 was assumed for samples with a negative result. The dams showed median Ct values of 16.1, 17.5 and 19.4, while in skin samples of the bull a median Ct value of 37.6 was observed. To determine the differences in DNA concentrations between different locations of the skin of the animals, a relative Ct (relCt) was determined by subtracting for each animal indv the MedianCtindv from each sample Ct. Analyses of the relCt values showed that the highest relative parasite DNA concentrations were observed in the categories 'OuterHindlegDistal', 'Rump', 'ForelegMiddle' and 'NoseFrontEars'. The relCt values in these categories differed statistically significantly from those determined for the categories 'VentralHeadNeck' and 'DorsalNeckWithersBackTail'. The

  12. Mechanism and determinants of nanoparticle penetration through human skin

    NASA Astrophysics Data System (ADS)

    Labouta, Hagar I.; El-Khordagui, Labiba K.; Kraus, Tobias; Schneider, Marc

    2011-12-01

    The ability of nanoparticles to penetrate the stratum corneum was the focus of several studies. Yet, there are controversial issues available for particle penetration due to different experimental setups. Meanwhile, there is little known about the mechanism and determinants of their penetration. In this paper the penetration of four model gold nanoparticles of diameter 6 and 15 nm, differing in surface polarity and the nature of the vehicle, through human skin was studied using multiphoton microscopy. This is in an attempt to profoundly investigate the parameters governing particle penetration through human skin. Our results imply that nanoparticles at this size range permeate the stratum corneum in a similar manner to drug molecules, mainly through the intercellular pathways. However, due to their particulate nature, permeation is also dependent on the complex microstructure of the stratum corneum with its tortuous aqueous and lipidic channels, as shown from our experiments performed using skin of different grades of barrier integrity. The vehicle (toluene-versus-water) had a minimal effect on skin penetration of gold nanoparticles. Other considerations in setting up a penetration experiment for nanoparticles were also studied. The results obtained are important for designing a new transdermal carrier and for a basic understanding of skin-nanoparticle interaction.

  13. Future Prospects for Scaffolding Methods and Biomaterials in Skin Tissue Engineering: A Review.

    PubMed

    Chaudhari, Atul A; Vig, Komal; Baganizi, Dieudonné Radé; Sahu, Rajnish; Dixit, Saurabh; Dennis, Vida; Singh, Shree Ram; Pillai, Shreekumar R

    2016-11-25

    Over centuries, the field of regenerative skin tissue engineering has had several advancements to facilitate faster wound healing and thereby restoration of skin. Skin tissue regeneration is mainly based on the use of suitable scaffold matrices. There are several scaffold types, such as porous, fibrous, microsphere, hydrogel, composite and acellular, etc., with discrete advantages and disadvantages. These scaffolds are either made up of highly biocompatible natural biomaterials, such as collagen, chitosan, etc., or synthetic materials, such as polycaprolactone (PCL), and poly-ethylene-glycol (PEG), etc. Composite scaffolds, which are a combination of natural or synthetic biomaterials, are highly biocompatible with improved tensile strength for effective skin tissue regeneration. Appropriate knowledge of the properties, advantages and disadvantages of various biomaterials and scaffolds will accelerate the production of suitable scaffolds for skin tissue regeneration applications. At the same time, emphasis on some of the leading challenges in the field of skin tissue engineering, such as cell interaction with scaffolds, faster cellular proliferation/differentiation, and vascularization of engineered tissues, is inevitable. In this review, we discuss various types of scaffolding approaches and biomaterials used in the field of skin tissue engineering and more importantly their future prospects in skin tissue regeneration efforts.

  14. 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.

  15. Sensitive skin and stratum corneum reactivity to household cleaning products.

    PubMed

    Goffin, V; Piérard-Franchimont, C; Piérard, G E

    1996-02-01

    Products intended for individuals with sensitive skin are being increasingly developed by formulators of household cleaning products. However, there is currently no consensus about the definition and recognition of the biological basis of sensitive skin. We sought to determine the relation between the nature of environmental threat perceived as aggressive by panelists, and the stratum corneum reactivity to household cleaning products as measured by the corneosurfametry test. Results indicate substantial differences in irritancy potential between proprietary products. Corneosurfametry data show significant differences in stratum corneum reactivity between, on the one hand, individuals with either non-sensitive skin or skin sensitive to climate/fabrics, and, on the other hand, individuals with detergent-sensitive skin. It is concluded that sensitive skin is not one single condition. Sound information in rating detergent-sensitive skin may be gained by corneosurfametry.

  16. Radiation sterilization of skin allograft

    NASA Astrophysics Data System (ADS)

    Kairiyama, E.; Horak, C.; Spinosa, M.; Pachado, J.; Schwint, O.

    2009-07-01

    In the treatment of burns or accidental loss of skin, cadaveric skin allografts provide an alternative to temporarily cover a wounded area. The skin bank facility is indispensable for burn care. The first human skin bank was established in Argentina in 1989; later, 3 more banks were established. A careful donor selection is carried out according to the national regulation in order to prevent transmissible diseases. As cadaveric human skin is naturally highly contaminated, a final sterilization is necessary to reach a sterility assurance level (SAL) of 10 -6. The sterilization dose for 106 batches of processed human skin was determined on the basis of the Code of Practice for the Radiation Sterilization of Tissue Allografts: Requirements for Validation and Routine Control (2004) and ISO 11137-2 (2006). They ranged from 17.6 to 33.4 kGy for bioburdens of >10-162.700 CFU/100 cm 2. The presence of Gram negative bacteria was checked for each produced batch. From the analysis of the experimental results, it was observed that the bioburden range was very wide and consequently the estimated sterilization doses too. If this is the case, the determination of a tissue-specific dose per production batch is necessary to achieve a specified requirement of SAL. Otherwise if the dose of 25 kGy is preselected, a standardized method for substantiation of this dose should be done to confirm the radiation sterilization process.

  17. An Overview of Ultraviolet B Radiation-Induced Skin Cancer Chemoprevention by Silibinin.

    PubMed

    Kumar, Rahul; Deep, Gagan; Agarwal, Rajesh

    2015-06-01

    Skin cancer incidences are rising worldwide, and one of the major causative factors is excessive exposure to solar ultraviolet radiation (UVR). Annually, ~5 million skin cancer patients are treated in United States, mostly with nonmelanoma skin cancer (NMSC), which is also frequent in other Western countries. As sunscreens do not provide adequate protection against deleterious effects of UVR, additional and alternative chemoprevention strategies are urgently needed to reduce skin cancer burden. Over the last couple of decades, extensive research has been conducted to understand the molecular basis of skin carcinogenesis, and to identifying novel agents which could be useful in the chemoprevention of skin cancer. In this regard, several natural non-toxic compounds have shown promising efficacy in preventing skin carcinogenesis at initiation, promotion and progression stages, and are considered important in better management of skin cancer. Consistent with this, we and others have studied and established the notable efficacy of natural flavonolignan silibinin against UVB-induced skin carcinogenesis. Extensive pre-clinical animal and cell culture studies report strong anti-inflammatory, anti-oxidant, DNA damage repair, immune-modulatory and anti-proliferative properties of silibinin. Molecular studies have identified that silibinin targets pleotropic signaling pathways including mitogenic, cell cycle, apoptosis, autophagy, p53, NF-κB, etc. Overall, the skin cancer chemopreventive potential of silibinin is well supported by comprehensive mechanistic studies, suggesting its greater use against UV-induced cellular damages and photocarcinogenesis.

  18. An Overview of Ultraviolet B Radiation-Induced Skin Cancer Chemoprevention by Silibinin

    PubMed Central

    Kumar, Rahul; Deep, Gagan; Agarwal, Rajesh

    2015-01-01

    Skin cancer incidences are rising worldwide, and one of the major causative factors is excessive exposure to solar ultraviolet radiation (UVR). Annually, ~5 million skin cancer patients are treated in United States, mostly with nonmelanoma skin cancer (NMSC), which is also frequent in other Western countries. As sunscreens do not provide adequate protection against deleterious effects of UVR, additional and alternative chemoprevention strategies are urgently needed to reduce skin cancer burden. Over the last couple of decades, extensive research has been conducted to understand the molecular basis of skin carcinogenesis, and to identifying novel agents which could be useful in the chemoprevention of skin cancer. In this regard, several natural non-toxic compounds have shown promising efficacy in preventing skin carcinogenesis at initiation, promotion and progression stages, and are considered important in better management of skin cancer. Consistent with this, we and others have studied and established the notable efficacy of natural flavonolignan silibinin against UVB-induced skin carcinogenesis. Extensive pre-clinical animal and cell culture studies report strong anti-inflammatory, anti-oxidant, DNA damage repair, immune-modulatory and anti-proliferative properties of silibinin. Molecular studies have identified that silibinin targets pleotropic signaling pathways including mitogenic, cell cycle, apoptosis, autophagy, p53, NF-κB, etc. Overall, the skin cancer chemopreventive potential of silibinin is well supported by comprehensive mechanistic studies, suggesting its greater use against UV-induced cellular damages and photocarcinogenesis. PMID:26097804

  19. Passive and iontophoretic transport through the skin polar pathway.

    PubMed

    Li, S K; Peck, K D

    2013-01-01

    The purpose of the present article is to briefly recount the contributions of Prof. William I. Higuchi to the area of skin transport. These contributions include developing fundamental knowledge of the barrier properties of the stratum corneum, mechanisms of skin transport, concentration gradient across skin in topical drug applications that target the viable epidermal layer, and permeation enhancement by chemical and electrical means. The complex and changeable nature of the skin barrier makes it difficult to assess and characterize the critical parameters that influence skin permeation. The systematic and mechanistic approaches taken by Dr. Higuchi in studying these parameters provided fundamental knowledge in this area and had a measured and lasting influence upon this field of study. This article specifically reviews the validation and characterization of the polar permeation pathway, the mechanistic model of skin transport, the influence of the dermis on the target skin concentration concept, and iontophoretic transport across the polar pathway of skin including the effects of electroosmosis and electropermeabilization. © 2013 S. Karger AG, Basel.

  20. Managing Occupational Irritant Contact Dermatitis Using a Two-Step Skincare Regimen Designed to Prevent Skin Damage and Support Skin Recovery.

    PubMed

    von Grote, Erika C; Palaniswarmy, Kiruthi; Meckfessel, Matthew H

    2016-12-01

    Occupational irritant contact dermatitis (ICD) affecting the hands is a common and difficult-to-manage condition. Occupations that necessitate contact with harsh chemicals, use of alcohol-based disinfectants, and frequent hand washing elevate the risk of ICD. Management strategies that do not adequately prevent accumulated damage and repair skin, can develop into chronic dermatoses which negatively impact work productivity and quality of life. A 2-step skin-care regimen (Excipial Daily Protection Hand Cream (EP) and Excipial Rapid Repair Hand Cream (ER), Galderma Laboratories, L.P.) has been developed as a daily-use management strategy to protect and repair vulnerable hands. The protective barrier cream is formulated with aluminum chlorohydrate and designed for pre-exposure application to enhance the skin's natural protective barrier and minimize excessive moisture while wearing protective gloves. The repair cream, a lipid-rich formulation, is intended for post-exposure application to rehydrate and facilitate the skin's natural healing process. The results of 3 clinical studies highlighted in this review demonstrate how the use of a 2-step skin-care regimen offers a greater protective effect against ICD than the use of barrier cream alone, and also how the formulation of the barrier cream used in these studies helps minimize the occlusion effect caused by gloves and does not interfere with the antibacterial efficacy of an alcohol-based hand sanitizer. This 2-step skin-care regimen is effectively designed to manage and minimize the risk of ICD development in a variety of patients and provides clinicians an additional tool for helping patients manage ICD. J Drugs Dermatol. 2016;15(12):1504-1510.

  1. 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.

  2. Short-term direct contact with soil and plant materials leads to an immediate increase in diversity of skin microbiota.

    PubMed

    Grönroos, Mira; Parajuli, Anirudra; Laitinen, Olli H; Roslund, Marja I; Vari, Heli K; Hyöty, Heikki; Puhakka, Riikka; Sinkkonen, Aki

    2018-05-29

    Immune-mediated diseases have increased during the last decades in urban environments. The hygiene hypothesis suggests that increased hygiene level and reduced contacts with natural biodiversity are related to the increase in immune-mediated diseases. We tested whether short-time contact with microbiologically diverse nature-based materials immediately change bacterial diversity on human skin. We tested direct skin contact, as two volunteers rubbed their hands with sixteen soil and plant based materials, and an exposure via fabric packets filled with moss material. Skin swabs were taken before and after both exposures. Next-generation sequencing showed that exposures increased, at least temporarily, the total diversity of skin microbiota and the diversity of Acidobacteria, Actinobacteria, Bacteroidetes, Proteobacteria and Alpha-, Beta- and Gammaproteobacteria suggesting that contact with nature-based materials modify skin microbiome and increase skin microbial diversity. Until now, approaches to cure or prevent immune system disorders using microbe-based treatments have been limited to use of a few microbial species. We propose that nature-based materials with high natural diversity, such as the materials tested here, might be more effective in modifying human skin microbiome, and eventually, in reducing immune system disorders. Future studies should investigate how long-term changes in skin microbiota are achieved and if the exposure induces beneficial changes in the immune system markers. © 2018 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

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

    NASA Astrophysics Data System (ADS)

    Sadowski, Łukasz; Stefaniuk, Damian

    2018-01-01

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

  4. Enhanced effect of fluorescent whitening agent on peroral infection for recombinant baculovirus in the host Bombyx mori L.

    PubMed

    Wang, Bing; Shang, Jinyan; Liu, Xunli; Cui, Weizheng; Wu, Xiaofeng; Zhao, Na

    2007-01-01

    The low efficiency of the oral infectivity of recombinant polyhedrin-negative baculovirus is a major bottleneck in the application of the baculovirus expression system in the silkworm (Bombyx mori L). In this study, the effects of a fluorescent whitening agent on improving the oral infection for the recombinant Bombyx mori nuclear polyhedrosis virus in silkworm larva and their possible mechanism were investigated. The results showed that the peroral infection can be remarkably enhanced by adding VBL into the larval artificial diet. The maximum infection rate reached as high as 90% with the concentration of VBL (1%), which was then considered as optimal. The total protease activity and pH value of the larval intestinal juice were found to be lower when compared to the control, indicating an abnormal physiological change of the larval digestive system by VBL, which, in turn, resulted in improved peroral infection of recombinant virus.

  5. Traditional Therapies for Skin Wound Healing.

    PubMed

    Pereira, Rúben F; Bártolo, Paulo J

    2016-05-01

    Significance: The regeneration of healthy and functional skin remains a huge challenge due to its multilayer structure and the presence of different cell types within the extracellular matrix in an organized way. Despite recent advances in wound care products, traditional therapies based on natural origin compounds, such as plant extracts, honey, and larvae, are interesting alternatives. These therapies offer new possibilities for the treatment of skin diseases, enhancing the access to the healthcare, and allowing overcoming some limitations associated to the modern products and therapies, such as the high costs, the long manufacturing times, and the increase in the bacterial resistance. This article gives a general overview about the recent advances in traditional therapies for skin wound healing, focusing on the therapeutic activity, action mechanisms, and clinical trials of the most commonly used natural compounds. New insights in the combination of traditional products with modern treatments and future challenges in the field are also highlighted. Recent Advances: Natural compounds have been used in skin wound care for many years due to their therapeutic activities, including anti-inflammatory, antimicrobial, and cell-stimulating properties. The clinical efficacy of these compounds has been investigated through in vitro and in vivo trials using both animal models and humans. Besides the important progress regarding the development of novel extraction methods, purification procedures, quality control assessment, and treatment protocols, the exact mechanisms of action, side effects, and safety of these compounds need further research. Critical Issues: The repair of skin lesions is one of the most complex biological processes in humans, occurring throughout an orchestrated cascade of overlapping biochemical and cellular events. To stimulate the regeneration process and prevent the wound to fail the healing, traditional therapies and natural products have been used

  6. [Skin cancer as occupational disease].

    PubMed

    Bauer, A

    2016-11-01

    The incidence of epithelial skin neoplasms, such as squamous cell carcinoma and basal cell carcinoma is significantly increasing worldwide. Leisure time solar UV exposure is causative in the overwhelming majority of cases in the general population; however, occupational exposure is responsible for a certain percentage of cases. Employees with a relevant exposure to polycyclic aromatic hydrocarbons in soot, raw paraffin, coal tar, anthracene, pitch or similar substances, to sunlight in outdoor occupations as well as to arsenic and ionizing radiation have a significantly increased risk to develop occupational skin cancer compared to the general population. In the official occupational disease list in the appendix of the German by-law on occupational diseases, the following occupational diseases concerning skin cancer are listed: BK 5102 "skin cancer and carcinoma in situ caused by soot, raw paraffin, coal tar, anthracene, pitch or similar substances" (e.g. various solid paraffins, asphalt and mazut as well as mineral oils, grease, cylinder and drilling oils), BK 5103 "squamous cell carcinoma or multiple actinic keratosis caused by natural UV radiation", BK 1108 "diseases caused by arsenic and its compounds" and BK 2402 "diseases caused by ionizing radiation". For further occupational exposure to carcinogenic substances and potential occupationally acquired skin tumors, no official lists are currently available. These cancers might be considered under a special opt out paragraph in the German Social Law (§ 9 para 2 SGB VII). Tumors in scars after occupational skin trauma or occupational burns are compensated as consequences of work accidents. The current official list of occupational skin cancers and new developments for expert opinions are described in this article.

  7. Contribution of Invariant Natural Killer T Cells to Skin Wound Healing.

    PubMed

    Tanno, Hiromasa; Kawakami, Kazuyoshi; Ritsu, Masae; Kanno, Emi; Suzuki, Aiko; Kamimatsuno, Rina; Takagi, Naoyuki; Miyasaka, Tomomitsu; Ishii, Keiko; Imai, Yoshimichi; Maruyama, Ryoko; Tachi, Masahiro

    2015-12-01

    In the present study, we determined the contribution of invariant natural killer T (iNKT) cells to the skin wound healing process. In iNKT cell-deficient (Jα18KO) mice lacking iNKT cells, wound closure was significantly delayed compared with wild-type mice. Collagen deposition, expression of α-smooth muscle actin and CD31, and wound breaking strength were significantly attenuated in Jα18KO mice. The adoptive transfer of liver mononuclear cells from wild-type but not from Jα18KO or interferon (IFN)-γ gene-disrupted (IFN-γKO) mice resulted in the reversal of this impaired wound healing in Jα18KO mice. IFN-γ expression was induced in the wounded tissues, which was significantly decreased at 6, 12, and 24 hours, but increased on day 3 after wounding in Jα18KO mice. The main source of the late-phase IFN-γ production in Jα18KO mice were neutrophils rather than NK cells and T cells. Administration of α-galactosylceramide, an activator of iNKT cells, resulted in the acceleration of wound healing on day 3 in wild-type mice. This effect was not observed in IFN-γKO mice. These results indicate that iNKT cells play important roles in wound healing. The iNKT cell-induced IFN-γ production may regulate the wound healing process in the early phase. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  8. Bioinspired fabrication and characterization of a synthetic fish skin for the protection of soft materials.

    PubMed

    Funk, Natasha; Vera, Marc; Szewciw, Lawrence J; Barthelat, Francois; Stoykovich, Mark P; Vernerey, Franck J

    2015-03-18

    The scaled skin of fish is a high-performance natural armor that represents a source of inspiration for novel engineering designs. In this paper, we present a biomimetic fish skin material, fabricated with a design and components that are simple, that achieves many of the advantageous attributes of natural materials, including the unique combination of flexibility and mechanical robustness. The bioinspired fish skin material is designed to replicate the structural, mechanical, and functional aspects of a natural teleost fish skin comprised of leptoid-like scales, similar to that of the striped red mullet Mullus surmuletus. The man-made fish skin material consists of a low-modulus elastic mesh or "dermis" layer that holds rigid, plastic scales. The mechanics of the synthetic material is characterized under in-plane, bending, and indentation modes of deformation and is successfully described by theoretical deformation models that have been developed. This combined experimental and modeling approach elucidates the critical mechanisms by which the composite material achieves its unique properties and provides design rules that allow for the engineering of scaled skins. Such artificial scaled skins that are flexible, lightweight, transparent, and robust under mechanical deformation may thus have potential as thin protective coatings for soft materials.

  9. PRFM enhance wound healing process in skin graft.

    PubMed

    Reksodiputro, Mirta; Widodo, Dini; Bashiruddin, Jenny; Siregar, Nurjati; Malik, Safarina

    2014-12-01

    Facial plastic and reconstructive surgery often used skin graft on defects that cannot be covered primarily by a local flap. However, wound healing using skin graft is slow, most of the time the graft is contractured and the take of graft is not optimal. Platelet rich fibrin matrix (PRFM) is a new generation of concentrated platelets that produce natural fibrin and reported to speed up the healing process. Application of PRFM in the skin graft implants is expected to increase the survival of the graft. We used porcine as animal models to elucidate the effect of autologous PRFM on wound healing in full-thickness (FTSG) and split-thickness (STSG) skin grafts. Survival level of the skin graft was determined by using ImageJ software based on the formation of collagen type 1 and graft take. We observed that the use of PRFM in FTSG and STSG increased type 1 collagen formation. We also found that PRFM addition in STSG gave the best skin graft take. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  10. Predicting chemically-induced skin reactions. Part II: QSAR models of skin permeability and the relationships between skin permeability and skin sensitization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Alves, Vinicius M.; Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599; Muratov, Eugene

    Skin permeability is widely considered to be mechanistically implicated in chemically-induced skin sensitization. Although many chemicals have been identified as skin sensitizers, there have been very few reports analyzing the relationships between molecular structure and skin permeability of sensitizers and non-sensitizers. The goals of this study were to: (i) compile, curate, and integrate the largest publicly available dataset of chemicals studied for their skin permeability; (ii) develop and rigorously validate QSAR models to predict skin permeability; and (iii) explore the complex relationships between skin sensitization and skin permeability. Based on the largest publicly available dataset compiled in this study, wemore » found no overall correlation between skin permeability and skin sensitization. In addition, cross-species correlation coefficient between human and rodent permeability data was found to be as low as R{sup 2} = 0.44. Human skin permeability models based on the random forest method have been developed and validated using OECD-compliant QSAR modeling workflow. Their external accuracy was high (Q{sup 2}{sub ext} = 0.73 for 63% of external compounds inside the applicability domain). The extended analysis using both experimentally-measured and QSAR-imputed data still confirmed the absence of any overall concordance between skin permeability and skin sensitization. This observation suggests that chemical modifications that affect skin permeability should not be presumed a priori to modulate the sensitization potential of chemicals. The models reported herein as well as those developed in the companion paper on skin sensitization suggest that it may be possible to rationally design compounds with the desired high skin permeability but low sensitization potential. - Highlights: • It was compiled the largest publicly-available skin permeability dataset. • Predictive QSAR models were developed for skin permeability. • No concordance between

  11. Double Back Cut in Post-mastectomy Breast Skin (Fish-Shaped Skin Paddle) in Delayed Pedicled TRAM Flap Breast Reconstruction.

    PubMed

    Berezovsky, Alexander Bogdanov; Pagkalos, Vasileios A; Shoham, Yaron; Krieger, Yuval; Silberstein, Eldad

    2015-08-01

    Breast reconstruction has become standard of care for female patients with breast cancer. The transverse rectus abdominis musculo-cutaneous flap (TRAMf) is the most common method of immediate or delayed autologous breast reconstruction following mastectomy. We share our experience with modified, double back cut of post-mastectomy skin in delayed pedicled TRAMf breast reconstruction, resulting in fish-shaped skin paddle. This sort of back cut is a simple, reliable way to obtain a natural, esthetically pleasant breast mound with inconspicuous hidden scars.

  12. Isolation of proanthocyanidins from red wine, and their inhibitory effects on melanin synthesis in vitro.

    PubMed

    Fujimaki, Takahiro; Mori, Shoko; Horikawa, Manabu; Fukui, Yuko

    2018-05-15

    The red wines made from Vitis vinifera were identified as skin-whitening effectors by using in vitro assays. OPCs in the wine were evaluated for tyrosinase activity and melanogenesis. Strong tyrosinase inhibitory activity was observed in fractions with high oligomeric proanthocyanidin (OPC) content. Among OPC dimers, a strong inhibitory effect on tyrosinase was observed with OPCs which contain (+)-catechin as an upper unit. Melanogenesis inhibitory effect was observed with OPCs which have (-)-epicatechin as upper units. Also, OPC trimers, upper and middle units joined with 4 → 8 bonds, showed stronger effects compared to trimers with 4 → 6 linkages. Interestingly, (-)-epicatechin-(4β → 8)-(-)-epicatechin 3-O-gallate, which is a unique component of grapes has potent inhibitory effects on both tyrosinase and melanogenesis. Our data provide structural information about such active compounds. These results suggest that red wines containing OPC, have high melanogenesis inhibitory effect and are supposed to have skin-whitening effect. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Future Prospects for Scaffolding Methods and Biomaterials in Skin Tissue Engineering: A Review

    PubMed Central

    Chaudhari, Atul A.; Vig, Komal; Baganizi, Dieudonné Radé; Sahu, Rajnish; Dixit, Saurabh; Dennis, Vida; Singh, Shree Ram; Pillai, Shreekumar R.

    2016-01-01

    Over centuries, the field of regenerative skin tissue engineering has had several advancements to facilitate faster wound healing and thereby restoration of skin. Skin tissue regeneration is mainly based on the use of suitable scaffold matrices. There are several scaffold types, such as porous, fibrous, microsphere, hydrogel, composite and acellular, etc., with discrete advantages and disadvantages. These scaffolds are either made up of highly biocompatible natural biomaterials, such as collagen, chitosan, etc., or synthetic materials, such as polycaprolactone (PCL), and poly-ethylene-glycol (PEG), etc. Composite scaffolds, which are a combination of natural or synthetic biomaterials, are highly biocompatible with improved tensile strength for effective skin tissue regeneration. Appropriate knowledge of the properties, advantages and disadvantages of various biomaterials and scaffolds will accelerate the production of suitable scaffolds for skin tissue regeneration applications. At the same time, emphasis on some of the leading challenges in the field of skin tissue engineering, such as cell interaction with scaffolds, faster cellular proliferation/differentiation, and vascularization of engineered tissues, is inevitable. In this review, we discuss various types of scaffolding approaches and biomaterials used in the field of skin tissue engineering and more importantly their future prospects in skin tissue regeneration efforts. PMID:27898014

  14. Evaluating the bonding of two adhesive systems to enamel submitted to whitening dentifrices.

    PubMed

    Briso, André Luiz Fraga; Toseto, Roberta Mariano; de Arruda, Alex Mendes; Tolentino, Patricia Ramos; de Alexandre, Rodrigo Sversut; dos Santos, Paulo Henrique

    2010-01-01

    The aim of this study was to evaluate by micro-shear bond strength test, the bond strength of composite resin restoration to enamel submitted to whitening dentifrices. Forty bovine teeth were embedded in polystyrene resin and polished. The specimens were randomly divided into eight groups (n=5), according to the dentifrice (carbamide peroxide, hydrogen peroxide and conventional dentifrice) and the adhesive system (Prime & Bond 2.1 and Adper Single Bond 2). Dentifrice was applied for 15 minutes a day, for 21 days. Thirty minutes after the last exposure to dentifrice, the samples were submitted to a bonding procedure with the respective adhesive system. After that, four buttons of resin were bonded in each sample using transparent cylindrical molds. After 24 hours, the teeth were submitted to the micro-shear bond strength test and subsequent analysis of the fracture mode. Data were submitted to analysis of variance and Fisher's PLSD test (alpha = 0.05). The micro-shear bond strength showed no difference between adhesives systems but a significant reduction was found between the control and carbamide groups (p = 0.0145) and the control and hydrogen groups (p = 0.0370). The evaluation of the failures modes showed that adhesive failures were predominant. Cohesive failures were predominant in group IV The use of dentifrice with peroxides can decrease bonding strength in enamel.

  15. Dermal Matrices and Bioengineered Skin Substitutes: A Critical Review of Current Options

    PubMed Central

    Hamdi, Moustapha; Abberton, Keren; Morrison, Wayne

    2015-01-01

    Background: Over recent decades, scientists and surgeons have collaborated to develop various bioengineered and synthetic products as an alternative to skin grafts. Despite the numerous articles and reviews written about dermal skin substitutes, there is no general consensus. Methods: This article reviews dermal skin scaffolds used in clinical applications and experimental settings. For scaffold evaluation, we focused on clinical and/or histological results, and conclusions are listed. Explanations for general trends were sought based on existing knowledge about tissue engineering principles and wound healing mechanisms. Results: Decellularized dermis seems to remain the best option with no other acellular scaffold being clinically proven to gain better results yet. In general, chemically cross-linked products were seen to be less effective in skin tissue engineering. Biocompatibility could be enhanced by preseeding substitutes with fibroblasts to allow some natural scaffold remodeling before product application. Conclusions: Skin substitutes are a useful tool in plastic and reconstructive surgery practices as an alternative to skin grafts. In the choice of substitute, the general plastic surgery principle of replacing like tissue with like tissue seems to be still standing, and products most resembling the natural dermal extracellular matrix should be preferred. PMID:25674365

  16. Fourier transform Raman spectroscopic studies of human and animal skins

    NASA Astrophysics Data System (ADS)

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

    1994-01-01

    The stratum corneum is the outermost layer of the skin and provides the principal barrier for the ingress of chemicals and environmental toxins into human and animal tissues. However, human skin has several advantages for the administration of therapeutic agents (transdermal drug delivery), but problems occur with the supply, storage, and biohazardous nature of human tissue. Hence, alternative animal tissues have been prepared to model drug diffusion across human skin but the molecular basis for comparison is lacking. Here, FT-Raman spectra of mammalian (human and pig) and reptilian (snake) skins have been obtained and the structural dissimilarities are correlated with drug diffusion studies across the tissues.

  17. Skin Diseases: Cross-section of human skin

    MedlinePlus

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

  18. In vitro permeation and disposition of niacinamide in silicone and porcine skin of skin barrier-mimetic formulations.

    PubMed

    Haque, Tasnuva; Lane, Majella E; Sil, Bruno C; Crowther, Jonathan M; Moore, David J

    2017-03-30

    Niacinamide (NIA) is an amide form of vitamin B3 which is used in cosmetic formulations to improve various skin conditions and it has also been shown to increase stratum corneum thickness following repeated application. In this study, three doses (5, 20 and 50μL per cm 2 ) of two NIA containing oil-in-water skin barrier-mimetic formulations were evaluated in silicone membrane and porcine ear skin and compared with a commercial control formulation. Permeation studies were conducted over 24h in Franz cells and at the end of the experiment membranes were washed and niacinamide was extracted. For the three doses, retention or deposition of NIA was generally higher in porcine skin compared with silicone membrane, consistent with the hydrophilic nature of the active. Despite the control containing a higher amount of active, comparable amounts of NIA were deposited in skin for all formulations for all doses; total skin absorption values (permeation and retention) of NIA were also comparable across all formulations. For infinite (50μL) and finite (5μL) doses the absolute permeation of NIA from the control formulation was significantly higher in porcine skin compared with both test formulations. This likely reflects differences in formulation components and/or presence of skin penetration enhancers in the formulations. Higher permeation for the 50 and 20μL dose was also evident in porcine skin compared with silicone membrane but the opposite is the case for the finite dose. The findings point to the critical importance of dose and occlusion when evaluating topical formulations in vitro and also the likelihood of exaggerated effects of excipients on permeation at infinite and pseudo-finite dose applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Predicting chemically-induced skin reactions. Part II: QSAR models of skin permeability and the relationships between skin permeability and skin sensitization

    PubMed Central

    Alves, Vinicius M.; Muratov, Eugene; Fourches, Denis; Strickland, Judy; Kleinstreuer, Nicole; Andrade, Carolina H.; Tropsha, Alexander

    2015-01-01

    Skin permeability is widely considered to be mechanistically implicated in chemically-induced skin sensitization. Although many chemicals have been identified as skin sensitizers, there have been very few reports analyzing the relationships between molecular structure and skin permeability of sensitizers and non-sensitizers. The goals of this study were to: (i) compile, curate, and integrate the largest publicly available dataset of chemicals studied for their skin permeability; (ii) develop and rigorously validate QSAR models to predict skin permeability; and (iii) explore the complex relationships between skin sensitization and skin permeability. Based on the largest publicly available dataset compiled in this study, we found no overall correlation between skin permeability and skin sensitization. In addition, cross-species correlation coefficient between human and rodent permeability data was found to be as low as R2=0.44. Human skin permeability models based on the random forest method have been developed and validated using OECD-compliant QSAR modeling workflow. Their external accuracy was high (Q2ext = 0.73 for 63% of external compounds inside the applicability domain). The extended analysis using both experimentally-measured and QSAR-imputed data still confirmed the absence of any overall concordance between skin permeability and skin sensitization. This observation suggests that chemical modifications that affect skin permeability should not be presumed a priori to modulate the sensitization potential of chemicals. The models reported herein as well as those developed in the companion paper on skin sensitization suggest that it may be possible to rationally design compounds with the desired high skin permeability but low sensitization potential. PMID:25560673

  20. Extraction of arbutin and its comparative content in branches, leaves, stems, and fruits of Japanese pear Pyrus pyrifolia cv. Kousui.

    PubMed

    Sasaki, Chizuru; Ichitani, Masaki; Kunimoto, Ko-Ki; Asada, Chikako; Nakamura, Yoshitoshi

    2014-01-01

    Arbutin is a tyrosinase inhibitor and is extensively used as a human skin-whitening agent. This study investigated the optimum conditions for extracting arbutin by ultrasonic homogenization from discarded branches pruned from Japanese pear (Pyrus pyrifolia cv. Kousui) trees. The arbutin content was measured in the branches and also in the leaves, stems, fruit peel, and fruit flesh.

  1. Spiritual and religious aspects of skin and skin disorders

    PubMed Central

    Shenefelt, Philip D; Shenefelt, Debrah A

    2014-01-01

    Skin and skin disorders have had spiritual aspects since ancient times. Skin, hair, and nails are visible to self and others, and touchable by self and others. The skin is a major sensory organ. Skin also expresses emotions detectable by others through pallor, coldness, “goose bumps”, redness, warmth, or sweating. Spiritual and religious significances of skin are revealed through how much of the skin has been and continues to be covered with what types of coverings, scalp and beard hair cutting, shaving and styling, skin, nail, and hair coloring and decorating, tattooing, and intentional scarring of skin. Persons with visible skin disorders have often been stigmatized or even treated as outcasts. Shamans and other spiritual and religious healers have brought about healing of skin disorders through spiritual means. Spiritual and religious interactions with various skin disorders such as psoriasis, leprosy, and vitiligo are discussed. Religious aspects of skin and skin diseases are evaluated for several major religions, with a special focus on Judaism, both conventional and kabbalistic. PMID:25120377

  2. Protective molecular mechanisms of resveratrol in UVR-induced Skin carcinogenesis.

    PubMed

    Aziz, Saba W; Aziz, Moammir H

    2018-01-01

    Skin cancer is a major health problem worldwide. It is the most common cancer in the United States and poses a significant healthcare burden. Excessive UVR exposure is the most common cause of skin cancer. Despite various precautionary measures to avoid direct UVR exposure, the incidence of skin cancer and mortality related to it remains high. Furthermore, the current treatment options are expensive and have side effects including toxicity to normal cells. Thus, a safe and effective approach is needed to prevent and treat skin cancer. Chemopreventive strategy using naturally occurring compounds, such as resveratrol, is a promising approach to reduce the incidence of UVR-induced skin cancer and delay its progression. This review highlights the current body of evidence related to chemopreventive role of resveratrol and its molecular mechanisms in UVR-induced skin carcinogenesis. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Impact of prebiotics and probiotics on skin health.

    PubMed

    Al-Ghazzewi, F H; Tester, R F

    2014-06-01

    This review discusses the role of pre- and probiotics with respect to improving skin health by modulating the cutaneous microbiota. The skin ecosystem is a complex environment covered with a diverse microbiota community. These are classified as either transient or resident, where some are considered as beneficial, some essentially neutral and others pathogenic or at least have the capacity to be pathogenic. Colonisation varies between different parts of the body due to different environmental factors. Pre- and probiotic beneficial effects can be delivered topically or systemically (by ingestion). The pre- and probiotics have the capacity to optimise, maintain and restore the microbiota of the skin in different ways. Topical applications of probiotic bacteria have a direct effect at the site of application by enhancing the skin natural defence barriers. Probiotics as well as resident bacteria can produce antimicrobial peptides that benefit cutaneous immune responses and eliminate pathogens. In cosmetic formulations, prebiotics can be applied to the skin microbiota directly and increase selectively the activity and growth of beneficial 'normal' skin microbiota. Little is known about the efficacy of topically applied prebiotics. Nutritional products containing prebiotics and/or probiotics have a positive effect on skin by modulating the immune system and by providing therapeutic benefits for atopic diseases. This review underlines the potential use of pre- and probiotics for skin health.

  4. Traditional Therapies for Skin Wound Healing

    PubMed Central

    Pereira, Rúben F.; Bártolo, Paulo J.

    2016-01-01

    Significance: The regeneration of healthy and functional skin remains a huge challenge due to its multilayer structure and the presence of different cell types within the extracellular matrix in an organized way. Despite recent advances in wound care products, traditional therapies based on natural origin compounds, such as plant extracts, honey, and larvae, are interesting alternatives. These therapies offer new possibilities for the treatment of skin diseases, enhancing the access to the healthcare, and allowing overcoming some limitations associated to the modern products and therapies, such as the high costs, the long manufacturing times, and the increase in the bacterial resistance. This article gives a general overview about the recent advances in traditional therapies for skin wound healing, focusing on the therapeutic activity, action mechanisms, and clinical trials of the most commonly used natural compounds. New insights in the combination of traditional products with modern treatments and future challenges in the field are also highlighted. Recent Advances: Natural compounds have been used in skin wound care for many years due to their therapeutic activities, including anti-inflammatory, antimicrobial, and cell-stimulating properties. The clinical efficacy of these compounds has been investigated through in vitro and in vivo trials using both animal models and humans. Besides the important progress regarding the development of novel extraction methods, purification procedures, quality control assessment, and treatment protocols, the exact mechanisms of action, side effects, and safety of these compounds need further research. Critical Issues: The repair of skin lesions is one of the most complex biological processes in humans, occurring throughout an orchestrated cascade of overlapping biochemical and cellular events. To stimulate the regeneration process and prevent the wound to fail the healing, traditional therapies and natural products have been used

  5. Operative treatment of functional facial skin disorders

    PubMed Central

    Scheithauer, Marc Oliver; Rettinger, Gerhard

    2005-01-01

    The skin is the principal interface between the body and the surrounding world and thus serves as a protective barrier against trauma, temperature extremes and radiation. With receptors for pressure, movement, heat and cold, it also acts as sensory organ and through sweat secretion plays a role in thermoregulation and electrolyte metabolism. Not all of these functions are relevant to facial skin, however, cosmetic aspects are of vital importance. Disorders primarily affect the protective skin function in defect and scar areas. For operative correction, the following principles should be applied: Minimization of scar development by adherence to indicated incision lines in the face, preferred use of local skin flaps for defect coverage in order to obtain optimal results regarding texture, complexion and sensitivity of skin, as well as consideration of aesthetic units. Recent developments in this field are tissue culture, occlusive dressings, and the use of growth factors. Age-related skin changes with impairment of cosmetic function are characterized by the development of creases and looseness of skin. Rejuvenation has become an important segment of skin surgery. For surface treatment, especially of creases and acne scars, various types of laser treatment are employed. Deeper lines can be filled with filler materials. The integration of the superficial musculoaponeurotic system (SMAS) into face lift procedures has lead to more viable and natural results. Due to protruding tissue, blepharoplasty of the upper lid is often carried out in combination with forehead lift and eyebrow lift procedures. The optimized use of growth factors and synthetic materials, which serve as a matrix, are aimed at skin replacement which mimics the quality and functions of skin as closely as possible. On the whole, however, the reconstruction of defect through local tissue transfer is still considered as the treatment of choice. PMID:22073066

  6. Oral intake of beet extract provides protection against skin barrier impairment in hairless mice.

    PubMed

    Kawano, Ken-Ichi; Umemura, Kazuo

    2013-05-01

    The epidermis acts as a functional barrier against the external environment. Disturbances in the function of this barrier cause water loss and increase the chances of penetration by various irritable stimuli, leading to skin diseases such as dry skin, atopic dermatitis, and psoriasis. Ceramides are a critical natural element of the protective epidermal barrier. The aim of this study was to evaluate whether the oral intake of beet (Beta vulgaris) extract, a natural product rich in glucosylceramide (GlcCer), may prevent disturbance in skin barrier function. When HR-1 hairless mice were fed a special diet (HR-AD), transepidermal water loss (TEWL) from the dorsal skin increased, with a compensatory increase in water intake after 5 weeks. Mice fed with HR-AD had dry skin with erythema and showed increased scratching behaviour. Histological examinations revealed a remarkable increase in the thickness of the skin at 8 weeks. Supplemental addition of beet extract, which contained GlcCer at a final concentration of 0.1%, significantly prevented an increase TEWL, water intake, cumulative scratching time, and epidermal thickness at 8 weeks. These results indicate that oral intake of beet extract shows potential for preventing skin diseases associated with impaired skin barrier function. Copyright © 2012 John Wiley & Sons, Ltd.

  7. [UV-irradiation-induced skin cancer as a new occupational disease].

    PubMed

    Diepgen, T L; Drexler, H; Elsner, P; Schmitt, J

    2015-03-01

    With the revision of the German Ordinance on Occupational Diseases, skin cancer due to UV irradiation was amended as a new occupational disease to the list of occupational diseases in Germany. The new occupational disease BK 5103 has the following wording: "Squamous cell carcinoma or multiple actinic keratosis of the skin caused by natural UV irradiation". Actinic keratoses are to be considered as multiple according to this new occupational diseases if they occur as single lesions of more than five annually, or are confluent in an area > 4 cm(2) (field cancerization). It is estimated that more than 2.5 million employees are exposed to natural UV irradiation due to their work (outdoor workers) in Germany and therefore have an increased risk of skin cancer. In this article the medical and technical prerequisites which have to be fulfilled for this new occupational disease in Germany are introduced.

  8. Allogeneic cultured keratinocytes vs. cadaveric skin to cover wide-mesh autogenous split-thickness skin grafts.

    PubMed

    Monstrey, S; Beele, H; Kettler, M; Van Landuyt, K; Blondeel, P; Matton, G; Naeyaert, J M

    1999-09-01

    Improved shock therapy has extended the limits of survival in patients with massive burns, and nowadays skin coverage has become the major problem in burn management. The use of mesh skin grafts is still the simplest technique to expand the amount of available donor skin. However, very wide-mesh skin grafts take a very long time to heal, often resulting in unaesthetic scar formation. On the other hand, allogeneic cultured keratinocytes have been reported as a natural source of growth factors and thus could be useful to improve wound healing of these wide-mesh grafts. A clinical study was performed to compare the use of cryopreserved allogeneic cultured keratinocytes vs. the traditional cadaveric skin as a double layer over widely expanded autogenous skin grafts. This procedure was performed in 18 pairs of full-thickness burn wounds (with similar depth and location) in 11 severely burned patients. Early clinical evaluation was made at 2, 3, and 4 to 5 weeks. Parameters such as epithelialization, granulation tissue formation, infection, and scar formation were evaluated. Biopsies were taken to compare the histological characteristics of the epidermis, the epidermal-dermal junction, and the dermis. Late evaluations were performed at 6 and 12 months regarding color, softness, thickness, and subjective feeling of the scar tissue. Aside from a faster (p < 0.05) epithelialization in the keratinocyte group at 2 weeks, there were no statistically different results in any of the early evaluated parameters, neither clinically nor histologically. At long-term follow-up, clinical results and scar characteristics were not significantly different in the two compared groups. It is concluded from the results of this study that, during the early phase, epithelialization was faster with allogeneic cultured keratinocytes compared with cadaveric skin. However, taking into account the substantial difference in costs, the described use of cryopreserved allogeneic cultured keratinocytes

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

    PubMed

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

    2017-05-30

    The percutaneous passage of poorly skin absorbed molecules can be improved using nanocarriers, particularly biodegradable polymeric nanospheres (NSs) or nanocapsules (NCs). However, penetration of the encapsulated molecules may be affected by other factors than the nanocarrier properties. To gain insight information on the skin absorption of two fluorescent cargos, DiIC 18 (5) and coumarin-6 were incorporated in NSs or NCs and topically applied on various human and porcine skin samples. 3D imaging techniques suggest that NSs and NCs enhanced deep dermal penetration of both probes similarly, when applied on excised human skin irrespective of the nature of the cargo. However, when ex vivo pig skin was utilized, the cutaneous absorption of DiIC 18 (5) was more pronounced by means of PLGA NCs than NSs. In contrast, PLGA NSs noticeably improved the porcine skin penetration of coumarin-6, as compared to the NCs. Furthermore, the porcine skin results were reproducible when triplicated whereas from various human skin samples, as expected, the results were not sufficiently reproducible and large deviations were observed. The overall findings from this comprehensive comparison emphasize the potential of PLGA NCs or NSs to promote cutaneous bioavailability of encapsulated drugs, exhibiting different physicochemical properties but depending on the nature of the skin. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Skin-specific training experience of workers assessed for contact dermatitis.

    PubMed

    Zack, B; Arrandale, V; Holness, D L

    2018-05-17

    Contact dermatitis is a common and preventable work-related disease. Skin-specific training may be effective for preventing occupational contact dermatitis, but little information is available regarding actual workplace training and its effectiveness. To describe workplace skin-specific training among workers with suspected contact dermatitis. Patch test patients being assessed for suspected contact dermatitis at an occupational health clinic in Toronto, Canada, completed a questionnaire on training experiences, workplace characteristics, exposures and skin protection practices. Of 175 patients approached, 122 (71%) workers completed questionnaires. Many (80%) had received general occupational health and safety and hazardous materials training (76%). Fewer (39%) received skin-specific training. Of those with work-related contact dermatitis, 52% did not receive skin-specific training. Skin-specific training was commonly provided by health and safety professionals or supervisors using video, classroom and online techniques. Content included glove use, exposure avoidance and hand washing information. Workers that received skin-specific training found it memorable (87%), useful (85%) and common sense in nature (100%). This study indicates gaps in workplace training on skin disease prevention for workers with contact dermatitis. Workers perceived skin-specific training to be useful. Understanding worker training experiences is important to prevention programme development and reducing work-related skin disease.

  11. Skin friction under pressure. The role of micromechanics

    NASA Astrophysics Data System (ADS)

    Leyva-Mendivil, Maria F.; Lengiewicz, Jakub; Limbert, Georges

    2018-03-01

    The role of contact pressure on skin friction has been documented in multiple experimental studies. Skin friction significantly raises in the low-pressure regime as load increases while, after a critical pressure value is reached, the coefficient of friction of skin against an external surface becomes mostly insensitive to contact pressure. However, up to now, no study has elucidated the qualitative and quantitative nature of the interplay between contact pressure, the material and microstructural properties of the skin, the size of an indenting slider and the resulting measured macroscopic coefficient of friction. A mechanistic understanding of these aspects is essential for guiding the rational design of products intended to interact with the skin through optimally-tuned surface and/or microstructural properties. Here, an anatomically-realistic 2D multi-layer finite element model of the skin was embedded within a computational contact homogenisation procedure. The main objective was to investigate the sensitivity of macroscopic skin friction to the parameters discussed above, in addition to the local (i.e. microscopic) coefficient of friction defined at skin asperity level. This was accomplished via the design of a large-scale computational experiment featuring 312 analyses. Results confirmed the potentially major role of finite deformations of skin asperities on the resulting macroscopic friction. This effect was shown to be modulated by the level of contact pressure and relative size of skin surface asperities compared to those of a rigid slider. The numerical study also corroborated experimental observations concerning the existence of two contact pressure regimes where macroscopic friction steeply and non-linearly increases up to a critical value, and then remains approximately constant as pressure increases further. The proposed computational modelling platform offers attractive features which are beyond the reach of current analytical models of skin

  12. Multispectral index for the remote detection of human skin signatures

    NASA Astrophysics Data System (ADS)

    Baranoski, Gladimir V. G.; Chen, Tenn F.

    2015-07-01

    We propose a multispectral index to assist the detection of human signatures in complex natural environments. Differently from previously proposed indices, it takes into account the spectral responses of human skin not only in the near infrared, but also in the visible region of the light spectrum. As a result, it can contribute to mitigate the chances of false alarms during time-critical search and rescue operations carried out in such environments. Our investigation is supported by the use of reflectance data measured for different skin specimens and natural materials such as sand, ocean water, melting snow, and forest vegetation. We believe that the observations reported in this work can be incorporated into the design of more effective procedures and devices for the differentiation of human targets from background materials commonly found in nature.

  13. Changing clothes easily: connexin41.8 regulates skin pattern variation.

    PubMed

    Watanabe, Masakatsu; Kondo, Shigeru

    2012-05-01

    The skin patterns of animals are very important for their survival, yet the mechanisms involved in skin pattern formation remain unresolved. Turing's reaction-diffusion model presents a well-known mathematical explanation of how animal skin patterns are formed, and this model can predict various animal patterns that are observed in nature. In this study, we used transgenic zebrafish to generate various artificial skin patterns including a narrow stripe with a wide interstripe, a narrow stripe with a narrow interstripe, a labyrinth, and a 'leopard' pattern (or donut-like ring pattern). In this process, connexin41.8 (or its mutant form) was ectopically expressed using the mitfa promoter. Specifically, the leopard pattern was generated as predicted by Turing's model. Our results demonstrate that the pigment cells in animal skin have the potential and plasticity to establish various patterns and that the reaction-diffusion principle can predict skin patterns of animals. © 2012 John Wiley & Sons A/S.

  14. 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.

  15. Land cover and forest connectivity alter the interactions among host, pathogen and skin microbiome.

    PubMed

    Becker, C G; Longo, A V; Haddad, C F B; Zamudio, K R

    2017-08-30

    Deforestation has detrimental consequences on biodiversity, affecting species interactions at multiple scales. The associations among vertebrates, pathogens and their commensal/symbiotic microbial communities (i.e. microbiomes) have important downstream effects for biodiversity conservation, yet we know little about how deforestation contributes to changes in host microbial diversity and pathogen abundance. Here, we tested the effects of landcover, forest connectivity and infection by the chytrid fungus Batrachochytrium dendrobatidis ( Bd ) on amphibian skin bacterial diversity along deforestation gradients in Brazilian landscapes. If disturbance to natural habitat alters skin microbiomes as it does in vertebrate host communities, then we would expect higher host bacterial diversity in natural forest habitats. Bd infection loads are also often higher in these closed-canopy forests, which may in turn impact skin-associated bacterial communities. We found that forest corridors shaped composition of host skin microbiomes; high forest connectivity predicted greater similarity of skin bacterial communities among host populations. In addition, we found that host skin bacterial diversity and Bd loads increased towards natural vegetation. Because symbiotic bacteria can potentially buffer hosts from Bd infection, we also evaluated the bi-directional microbiome- Bd link but failed to find a significant effect of skin bacterial diversity reducing Bd infections. Although weak, we found support for Bd increasing bacterial diversity and/or for core bacteria dominance reducing Bd loads. Our research incorporates a critical element in the study of host microbiomes by linking environmental heterogeneity of landscapes to the host-pathogen-microbiome triangle. © 2017 The Author(s).

  16. Modeling of bioheat equation for skin and a preliminary study on a noninvasive diagnostic method for skin burn wounds.

    PubMed

    Lee, Shong-Leih; Lu, Yung-Hsiang

    2014-08-01

    Heat transfer in a unit three-dimensional skin tissue with an embedded vascular system of actual histology structure is computed in the present work. The tissue temperature and the blood temperatures in artery and vein vessels are solved with a multi-grid system. The mean temperature of the tissue over the cross-section of the unit skin area is evaluated. The resulting one-dimensional function is regarded as the temperature of healthy tissue (or injured skin but the blood perfusion is still normally working) for large area of skin in view of the symmetric and periodic structure of the paired artery-vein vessels in nature. A three-dimensional bioheat equation then is formulated by the superposition of the skin burn wound effect and the healthy skin temperature with and without thermal radiation exposure. When this bioheat equation is employed to simulate ADT process on burn wounds, the decaying factor of the skin surface temperature is found to be a sharply decreasing function of time in the self-cooling stage after a thermal radiation heating. Nevertheless, the boundary of non-healing (needing surgery) and healing regions in a large burn wound can be estimated by tracking the peak of the gradient of decaying factor within 30 s after the thermal radiation is turned off. Experimental studies on the full ADT procedure are needed to justify the assumptions in the present computation. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  17. Phytonutrients for controlling starch digestion: evaluation of grape skin extract.

    PubMed

    Miao, Ming; Jiang, Huan; Jiang, Bo; Zhang, Tao; Cui, Steve W; Jin, Zhengyu

    2014-02-15

    The objective of this work was to evaluate the structure-function relationship between grape skin extract and human α-amylase. The grape skin extract was characterised as resveratrol-3-O-glucoside by RP-HPLC-ESI-MS, which showed strong inhibition towards α-amylase and the IC50 value was 1.35 mg/ml. The kinetic results demonstrated grape skin extract obeyed the non-competitive mode against amylase. Fluorescence data revealed the ability of grape skin binding to amylase belonged to static quenching mechanism with a complex formation and there was only one binding site in α-amylase for grape skin extract. Docking study showed a best pose with total energy value of -118.3 kJ/mol and grape skin extract interacted with side chain of Asp300 with hydrogen bonds and Van der Waals forces. This preliminary observation provides the basis for further evaluation of the suitability of grape skin extract as natural inhibitor with potential health benefits. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  18. A strong and stretchable self-healing film with self-activated pressure sensitivity for potential artificial skin applications

    PubMed Central

    Hou, Chengyi; Huang, Tao; Wang, Hongzhi; Yu, Hao; Zhang, Qinghong; Li, Yaogang

    2013-01-01

    Artificial skin, which mimics the functions of natural skin, will be very important in the future for robots used by humans in daily life. However, combining skin's pressure sensitivity and mechanical self-healing properties in a man-made material remains a challenging task. Here, we show that graphene and polymers can be integrated into a thin film which mimics both the mechanical self-healing and pressure sensitivity behavior of natural skin without any external power supply. Its ultimate strain and tensile strength are even two and ten times larger than the corresponding values of human skin, respectively. It also demonstrates highly stable sensitivity to a very light touch (0.02 kPa), even in bending or stretching states. PMID:24190511

  19. Potential biomedical applications of marine algae.

    PubMed

    Wang, Hui-Min David; Li, Xiao-Chun; Lee, Duu-Jong; Chang, Jo-Shu

    2017-11-01

    Functional components extracted from algal biomass are widely used as dietary and health supplements with a variety of applications in food science and technology. In contrast, the applications of algae in dermal-related products have received much less attention, despite that algae also possess high potential for the uses in anti-infection, anti-aging, skin-whitening, and skin tumor treatments. This review, therefore, focuses on integrating studies on algae pertinent to human skin care, health and therapy. The active compounds in algae related to human skin treatments are mentioned and the possible mechanisms involved are described. The main purpose of this review is to identify serviceable algae functions in skin treatments to facilitate practical applications in this high-potential area. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Skin disease in Gulf war veterans.

    PubMed

    Higgins, E M; Ismail, K; Kant, K; Harman, K; Mellerio, J; Du Vivier, A W P; Wessely, S

    2002-10-01

    Gulf war veterans report more symptomatic ill-health than other military controls, and skin disease is one of the most frequent reasons for military personnel to seek medical care. To compare the nature and prevalence of skin disease in UK Gulf veterans with non-Gulf veterans, and to assess whether skin disease is associated with disability. Prospective case comparison study. Disabled (n=111) and non-disabled (n=98) Gulf veterans and disabled non-Gulf veterans (n=133) were randomly selected from representative cohorts of those who served in the Gulf conflict 1990-1991, UN Bosnia Peacekeeping Force 1992-1997, or veterans in active service between 1990-91, but not deployed to the Gulf. Disability was defined as reduced physical functioning as measured by the Short Form 36 [score <72.2]. All subjects recruited were examined by a dermatologist, blind to the military and health status of the veteran. The prevalences of skin disease in disabled Gulf, non-disabled Gulf and disabled non-Gulf veterans were 47.7, 36.7, and 42.8% respectively. Seborrhoeic dermatitis was twice as common as expected in the Gulf veterans (both disabled and non-disabled). Skin disease does not appear to be contributing to ill health in Gulf war veterans, with the exception of an unexplained two-fold increase in seborrhoeic dermatitis.

  1. Shikonin Suppresses Skin Carcinogenesis via Inhibiting Cell Proliferation

    PubMed Central

    Ren, Amy; Li, Teena; Jin, Rong; Li, Guohong; Gu, Xin; Shi, Runhua; Zhao, Yunfeng

    2015-01-01

    The M2 isoform of pyruvate kinase M2 (PKM2) has been shown to be up-regulated in human skin cancers. To test whether PKM2 may be a target for chemoprevention, shikonin, a natural product from the root of Lithospermum erythrorhizon and a specific inhibitor of PKM2, was used in a chemically-induced mouse skin carcinogenesis study. The results revealed that shikonin treatment suppressed skin tumor formation. Morphological examinations and immunohistochemical staining of the skin epidermal tissues suggested that shikonin inhibited cell proliferation without inducing apoptosis. Although shikonin alone suppressed PKM2 activity, it did not suppress tumor promoter-induced PKM2 activation in the skin epidermal tissues at the end of the skin carcinogenesis study. To reveal the potential chemopreventive mechanism of shikonin, an antibody microarray analysis was performed, and the results showed that the transcription factor ATF2 and its downstream target Cdk4 were up-regulated by chemical carcinogen treatment; whereas these up-regulations were suppressed by shikonin. In a promotable skin cell model, the nuclear levels of ATF2 were increased during tumor promotion, whereas this increase was inhibited by shikonin. Furthermore, knockdown of ATF2 decreased the expression levels of Cdk4 and Fra-1 (a key subunit of the activator protein 1. In summary, these results suggest that shikonin, rather than inhibiting PKM2 in vivo, suppresses the ATF2 pathway in skin carcinogenesis. PMID:25961580

  2. Temperature variation, bacterial diversity and fungal infection dynamics in the amphibian skin.

    PubMed

    Longo, Ana V; Zamudio, Kelly R

    2017-09-01

    Host-associated bacterial communities on the skin act as the first line of defence against invading pathogens. Yet, for most natural systems, we lack a clear understanding of how temperature variability affects structure and composition of skin bacterial communities and, in turn, promotes or limits the colonization of opportunistic pathogens. Here, we examine how natural temperature fluctuations might be related to changes in skin bacterial diversity over time in three amphibian populations infected by the pathogenic fungus Batrachochytrium dendrobatidis (Bd). Our focal host species (Eleutherodactylus coqui) is a direct-developing frog that has suffered declines at some populations in the last 20 years, while others have not experienced any changes. We quantified skin bacterial alpha- and beta-diversity at four sampling time points, a period encompassing two seasons and ample variation in natural infections and environmental conditions. Despite the different patterns of infection across populations, we detected an overall increase in bacterial diversity through time, characterized by the replacement of bacterial operational taxonomic units (OTUs). Increased frog body temperatures possibly allowed the colonization of bacteria as well as the recruitment of a subset of indicator OTUs, which could have promoted the observed changes in diversity patterns. Our results suggest that natural environmental fluctuations might be involved in creating opportunities for bacterial replacement, potentially attenuating pathogen transmission and thus contributing to host persistence in E. coqui populations. © 2017 John Wiley & Sons Ltd.

  3. Hydrophobicity and biofilm formation of lipophilic skin corynebacteria.

    PubMed

    Kwaszewska, Anna K; Brewczyńska, Anna; Szewczyk, Eligia M

    2006-01-01

    Lipophilic corynebacteria isolated as natural flora of human skin were examined. Among 119 assayed strains 94% presented a hydrophobic cell surface and 75.6% were able to form biofilms. These attributes, as well as aggregation in liquid media, were statistically connected with each other and promote the developing of biofilms on solid surfaces. This was characteristic of all the lipophilic Corynebacterium species found on human skin that were examined in this study. C. jeikeium and CDC group G2 strains dominated in this population, and they could be responsible for investigated features in the whole lipophilic skin bacterial population. These two groups are the most common coryneform bacteria isolated from nosocomial infections and these attributes most likely promote them to cause opportunistic infections.

  4. The skin reservoir of sulphur mustard.

    PubMed

    Hattersley, I J; Jenner, J; Dalton, C; Chilcott, R P; Graham, J S

    2008-09-01

    Studies of the percutaneous reservoir of sulphur mustard (HD) formed during absorption carried out during WWI and WWII are inconclusive. More recent studies have indicated that a significant amount of unreacted HD remains in human epidermal membranes during percutaneous penetration studies in vitro. The present study investigated the nature and persistence of the HD reservoir formed during in vitro penetration studies using dermatomed slices of human and pig skin (0.5mm thick). Amounts of (14)C-HD that (a) penetrated, (b) remained on the surface, (c) were extractable from and (d) remained in the skin after extraction were estimated by liquid scintillation counting (confirmed using GC-MS analysis). The results demonstrated that there is a reservoir of HD in human and pig skin for up to 24 h after contamination of the skin surface in vitro with liquid agent. At least some of this reservoir could be extracted with acetonitrile, and the amounts of extracted and unextracted HD exceed the amount required to produce injury in vivo by at least 20 fold. The study demonstrated the presence of a reservoir whether the skin was covered (occluded) or left open to the air (unoccluded). The study concluded that the extractable reservoir was significant in terms of the amount of HD required to induce a vesicant response in human skin. The extractable reservoir was at least 20 times the amount required per cm(2) estimated to cause a response in all of the human population, as defined by studies carried out in human volunteers during the 1940s.

  5. Daily intake of Jeju groundwater improves the skin condition of the model mouse for human atopic dermatitis.

    PubMed

    Tanaka, Akane; Jung, Kyungsook; Matsuda, Akira; Jang, Hyosun; Kajiwara, Naoki; Amagai, Yosuke; Oida, Kumiko; Ahn, Ginnae; Ohmori, Keitaro; Kang, Kyung-goo; Matsuda, Hiroshi

    2013-03-01

    Drinking water is an important nutrient for human health. The mineral ingredients included in drinking water may affect the physical condition of people. Various kinds of natural water are in circulation as bottled water in developed countries; however, its influence on clinical conditions of patients with certain diseases has not been fully evaluated. In this study, effects of the natural groundwater from Jeju Island on clinical symptoms and skin barrier function in atopic dermatitis (AD) were evaluated. NC/Tnd mice, a model for human AD, with moderate to severe dermatitis were used. Mice were given different natural groundwater or tap water for 8 weeks from 4 weeks of age. Clinical skin severity scores were recorded every week. Scratching analysis and measurement of transepidermal water loss were performed every other week. The pathological condition of the dorsal skin was evaluated histologically. Real-time polymerase chain reaction analysis was performed for cytokine expression in the affected skin. The epidermal hyperplasia and allergic inflammation were reduced in atopic mice supplied with Jeju groundwater when compared to those supplied with tap water or other kinds of natural groundwater. The increase in scratching behavior with the aggravation of clinical severity of dermatitis was favorably controlled. Moreover, transepidermal water loss that reflects skin barrier function was recovered. The early inflammation and hypersensitivity in the atopic skin was alleviated in mice supplied with Jeju groundwater, suggesting its profitable potential on the daily care of patients with skin troubles including AD. © 2013 Japanese Dermatological Association.

  6. 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.

  7. Improved cosmetic activity by optimizing the Lithospermum erythrorhizon extraction process.

    PubMed

    Kim, Ji Seon; Seo, Yong Chang; No, Ra Hwan; Lee, Hyeon Yong

    2015-01-01

    This study was conducted to expand the use of Lithospermum erythrorhizon, which is a good source of natural dye, in skin whitening and immune activation cosmetics. The goal was to provide cosmeceutical data about the extraction yield and shikonin contents of this plant by optimizing the ultrasonic extraction and high pressure extraction conditions. Under optimal extraction conditions, which consisted of 500 MPa for 60 min and 120 kHz for 90 min, 27.49 and 3.19 % (w/w) of the highest extraction yield and shikonin contents were obtained, compared to 16.32 and 1.81 % from a conventional ethanol extract (EE) control. Hyaluronidase inhibition activity was measured as 44.24 % after adding 1.0 mg/ml of ethanol extract, but it was as high as 64.19 % when using extract produced by ultrasonication with high pressure extraction (UE + HPE). The MMP-1 expression levels from skin fibroblast cells (CCD-986sk) treated with or without UV irradiation were also lowered by as much as 110.6 % after adding 1.0 mg/ml of the UE + HPE extract, relative to 126.9 % from the EE. After UVA exposure, prostaglandin E2 production from RAW 264.7 was also lower, at 110.6 %, which also indicates that the extract from the UE + HPE process enhanced skin immune activation activities. For the skin whitening activity, tyrosinase inhibitory activity was observed at 67.15 % in the HPE + UE extract, which was ca. 20 % higher than that of the EE extract (57.48 %). To reduce melanin production in Clone M-3 cells, 79.5 % of the melanin production was estimated after adding 1.0 mg/ml of the UE + HPE extract compared to that of the control (no treatment), which was similar to the 77.4 % result found in an ascorbic acid positive control. The highest shikonin secretion was conclusively obtained under the optimal conditions and resulted in a significant improvement of the cosmetic activities of L. erythrorhizon extracts.

  8. Lumpy skin disease: attempted propagation in tick cell lines and presence of viral DNA in field ticks collected from naturally-infected cattle.

    PubMed

    Tuppurainen, E S M; Venter, E H; Coetzer, J A W; Bell-Sakyi, L

    2015-03-01

    Lumpy skin disease (LSD) is of substantial economic importance for the cattle industry in Africa and the Near and Middle East. Several insect species are thought to transmit the disease mechanically. Recent transmission studies have demonstrated the first evidence for a role of hard (ixodid) ticks as vectors of lumpy skin disease virus (LSDV). The aim of this study was to attempt in vitro growth of the virus in Rhipicephalus spp. tick cell lines and investigate in vivo the presence of the virus in ticks collected from cattle during LSD outbreaks in Egypt and South Africa. No evidence was obtained for replication of LSDV in tick cell lines although the virus was remarkably stable, remaining viable for 35 days at 28°C in tick cell cultures, in growth medium used for tick cells and in phosphate buffered saline. Viral DNA was detected in two-thirds of the 56 field ticks, making this the first report of the presence of potentially virulent LSDV in ticks collected from naturally infected animals. Crown Copyright © 2014. Published by Elsevier GmbH. All rights reserved.

  9. Lumpy skin disease: Attempted propagation in tick cell lines and presence of viral DNA in field ticks collected from naturally-infected cattle

    PubMed Central

    Tuppurainen, E.S.M.; Venter, E.H.; Coetzer, J.A.W.; Bell-Sakyi, L.

    2015-01-01

    Lumpy skin disease (LSD) is of substantial economic importance for the cattle industry in Africa and the Near and Middle East. Several insect species are thought to transmit the disease mechanically. Recent transmission studies have demonstrated the first evidence for a role of hard (ixodid) ticks as vectors of lumpy skin disease virus (LSDV). The aim of this study was to attempt in vitro growth of the virus in Rhipicephalus spp. tick cell lines and investigate in vivo the presence of the virus in ticks collected from cattle during LSD outbreaks in Egypt and South Africa. No evidence was obtained for replication of LSDV in tick cell lines although the virus was remarkably stable, remaining viable for 35 days at 28 °C in tick cell cultures, in growth medium used for tick cells and in phosphate buffered saline. Viral DNA was detected in two-thirds of the 56 field ticks, making this the first report of the presence of potentially virulent LSDV in ticks collected from naturally infected animals. PMID:25468765

  10. 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 ...

  11. Combination of 4-hydroxyanisole and all-trans retinoic acid produces synergistic skin depigmentation in swine.

    PubMed

    Nair, X; Parab, P; Suhr, L; Tramposch, K M

    1993-08-01

    A combination of 4-hydroxyanisole (4HA) and all-trans retinoic acid (TRA) was found to synergistically cause moderate to complete depigmentation of Yucatan swine skin. Two hyperpigmentation models were used: Natural dark-skinned swine, a potential model for melasma-like disorders, and ultraviolet light-stimulated hyperpigmentation, a model of solar lentigines. Test materials were applied twice daily, 5 d/week, to dorsal flank skin. Application sites were graded at weekly intervals for skin color using a 0 to 4 grading scale. After 8 weeks of treatment of naturally dark swine skin, a combination of 2% 4HA and 0.01% TRA produced grade 2 hypopigmentation (definite but moderate hypopigmentation). In contrast, 2% 4HA alone or 0.01% TRA alone did not produce significant hypopigmentation. After cessation of treatment, the 4HA/TRA-treated sites reverted to normal color within 7-12 weeks. The 4HA/TRA combination completely reversed the hyperpigmentation induced by ultraviolet light after 8 weeks of treatment. In vitro skin-penetration studies using hairless mouse and human skin show that skin penetration of 4HA was not significantly affected by adding 0.01% TRA. These data suggest that the observed synergy is not due to enhanced bioavailability of 4HA. We have demonstrated that combining low concentrations of 4HA and TRA results in effective skin lightening without causing irreversible depigmentation and with minimal local skin irritation.

  12. Skin blotting: a noninvasive technique for evaluating physiological skin status.

    PubMed

    Minematsu, Takeo; Horii, Motoko; Oe, Makoto; Sugama, Junko; Mugita, Yuko; Huang, Lijuan; Nakagami, Gojiro; Sanada, Hiromi

    2014-06-01

    The skin performs important structural and physiological functions, and skin assessment represents an important step in identifying skin problems. Although noninvasive techniques for assessing skin status exist, no such techniques for monitoring its physiological status are available. This study aimed to develop a novel skin-assessment technique known as skin blotting, based on the leakage of secreted proteins from inside the skin following overhydration in mice. The applicability of this technique was further investigated in a clinical setting. Skin blotting involves 2 steps: collecting proteins by attaching a damp nitrocellulose membrane to the surface of the skin, and immunostaining the collected proteins. The authors implanted fluorescein-conjugated dextran (F-DEX)-containing agarose gels into mice and detected the tissue distribution of F-DEX under different blotting conditions. They also analyzed the correlations between inflammatory cytokine secretion and leakage following ultraviolet irradiation in mice and in relation to body mass index in humans. The F-DEX in mice was distributed in the deeper and shallower layers of skin and leaked through the transfollicular and transepidermal routes, respectively. Ultraviolet irradiation induced tumor necrosis factor secretion in the epidermis in mice, which was detected by skin blotting, whereas follicular tumor necrosis factor was associated with body mass index in obese human subjects. These results support the applicability of skin blotting for skin assessment. Skin blotting represents a noninvasive technique for assessing skin physiology and has potential as a predictive and diagnostic tool for skin disorders.

  13. Recent Advances in Skin-Inspired Sensors Enabled by Nanotechnology

    NASA Astrophysics Data System (ADS)

    Loh, Kenneth J.; Azhari, Faezeh

    2012-07-01

    The highly optimized performance of nature's creations and biological assemblies has inspired the development of their bio-inspired artificial counterparts that can potentially outperform conventional systems. In particular, the skin of humans, animals, and insects exhibits unique functionalities and properties and has subsequently led to active research in developing skin-inspired sensors. This paper presents a summary of selected work related to skin-inspired tactile, distributed strain, and artificial hair cell flow sensors, with a particular focus on technologies enabled by recent advancements in the nanotechnology domain. The purpose is not to present a comprehensive review on this broad subject matter but rather to use selected work to outline the diversity of current research activities.

  14. A fermented barley and soybean formula enhances skin hydration.

    PubMed

    Lee, Sein; Kim, Jong-Eun; Suk, Sujin; Kwon, Oh Wook; Park, Gaeun; Lim, Tae-Gyu; Seo, Sang Gwon; Kim, Jong Rhan; Kim, Dae Eung; Lee, Miyeong; Chung, Dae Kyun; Jeon, Jong Eun; Cho, Dong Woon; Hurh, Byung Serk; Kim, Sun Yeou; Lee, Ki Won

    2015-09-01

    Skin hydration is one of the primary aims of beauty and anti-aging treatments. Barley (Hordeum vulgare) and soybean (Glycine max) are major food crops, but can also be used as ingredients for the maintenance of skin health. We developed a natural product-based skin treatment using a barley and soybean formula (BS) incorporating yeast fermentation, and evaluated its skin hydration effects as a dietary supplement in a clinical study. Participants ingested a placebo- (n = 33) or BS- (3 g/day) containing drink (n = 32) for 8 weeks. A significant increase in hydration in the BS group as compared to the placebo group was observed on the faces of subjects after 4 and 8 weeks, and on the forearm after 4 weeks. Decreases in stratum corneum (SC) thickness were also observed on the face and forearm. BS enhanced hyaluronan (HA) and skin barrier function in vitro and reduced Hyal2 expression in human dermal fibroblasts (HDF). BS also recovered ultraviolet (UV) B-induced downregulation of HA in HaCaT cells. These results suggest that BS has promising potential for development as a health functional food to enhance skin health.

  15. A fermented barley and soybean formula enhances skin hydration

    PubMed Central

    Lee, Sein; Kim, Jong-Eun; Suk, Sujin; Kwon, Oh Wook; Park, Gaeun; Lim, Tae-gyu; Seo, Sang Gwon; Kim, Jong Rhan; Kim, Dae Eung; Lee, Miyeong; Chung, Dae Kyun; Jeon, Jong Eun; Cho, Dong Woon; Hurh, Byung Serk; Kim, Sun Yeou; Lee, Ki Won

    2015-01-01

    Skin hydration is one of the primary aims of beauty and anti-aging treatments. Barley (Hordeum vulgare) and soybean (Glycine max) are major food crops, but can also be used as ingredients for the maintenance of skin health. We developed a natural product-based skin treatment using a barley and soybean formula (BS) incorporating yeast fermentation, and evaluated its skin hydration effects as a dietary supplement in a clinical study. Participants ingested a placebo- (n = 33) or BS- (3 g/day) containing drink (n = 32) for 8 weeks. A significant increase in hydration in the BS group as compared to the placebo group was observed on the faces of subjects after 4 and 8 weeks, and on the forearm after 4 weeks. Decreases in stratum corneum (SC) thickness were also observed on the face and forearm. BS enhanced hyaluronan (HA) and skin barrier function in vitro and reduced Hyal2 expression in human dermal fibroblasts (HDF). BS also recovered ultraviolet (UV) B-induced downregulation of HA in HaCaT cells. These results suggest that BS has promising potential for development as a health functional food to enhance skin health. PMID:26388675

  16. Rapid Sampling of Molecules via Skin for Diagnostic and Forensic Applications

    PubMed Central

    Paliwal, Sumit; Ogura, Makoto

    2010-01-01

    ABSTRACT Purpose Skin provides an excellent portal for diagnostic monitoring of a variety of entities; however, there is a dearth of reliable methods for patient-friendly sampling of skin constituents. This study describes the use of low-frequency ultrasound as a one-step methodology for rapid sampling of molecules from the skin. Methods Sampling was performed using a brief exposure of 20 kHz ultrasound to skin in the presence of a sampling fluid. In vitro sampling from porcine skin was performed to assess the effectiveness of the method and its ability to sample drugs and endogenous epidermal biomolecules from the skin. Dermal presence of an antifungal drug—fluconazole and an abused substance, cocaine—was assessed in rats. Results Ultrasonic sampling captured the native profile of various naturally occurring moisturizing factors in skin. A high sampling efficiency (79 ± 13%) of topically delivered drug was achieved. Ultrasound consistently sampled greater amounts of drug from the skin compared to tape stripping. Ultrasonic sampling also detected sustained presence of cocaine in rat skin for up to 7 days as compared to its rapid disappearance from the urine. Conclusions Ultrasonic sampling provides significant advantages including enhanced sampling from deeper layers of skin and high temporal sampling sensitivity. PMID:20238151

  17. Skin metastases from lung cancer: a case report.

    PubMed

    Pajaziti, Laura; Hapçiu, Syzana Rexhepi; Dobruna, Shkendije; Hoxha, Naim; Kurshumliu, Fisnik; Pajaziti, Artina

    2015-04-11

    Lung cancer is one of the most frequent malignancies, with high mortality rates. It can metastasize in almost all organs, but more often invades hilar nodes, liver, adrenal glands, bones and brain. There are various data on the incidence of lung cancer metastases in the skin. In 1-12% of patients with lung cancer are developed skin metastases. Metastases in the skin may be the first sign of lung cancer. Forty-five years old Albanian male, smoker, was admitted to our department with multiple nodules localized in the skin of the head, neck, back and chest. The nodules measuring 5-15 millimeters in greatest dimension were round and skin-colored, with telangiectasias, firm and tender. They appeared in an eruptive form about two weeks before being admitted at our hospital. In addition, the patient exhibited signs of weight loss, anorexia and fatigue. Excisional biopsy was performed to one of the lesions. Histopathology confirmed metastatic nature of the lesion namely, malignant tumor of neuroendocrine phenotype consistent with small-cell carcinoma. Chest X-ray and computed tomography revealed an expansive process in the 7(th) segment of the left lung, left hilar and mediastinal lymphadenopathy and a suspicious initial secondary deposit in the left adrenal gland. The patient was referred to the department of oncology for further treatment. After the third cycle of chemotherapy, the magnetic resonance imaging revealed brain metastases. The patient passed away four months after the diagnosis of lung cancer first presented with skin metastases. Metastases in skin may be the first sign of lung cancer. Although rare appearing, we should raise suspicion in cases of atypical lesions in the skin not only of the smokers, but also of the non-smokers. Skin metastases from small-cell lung carcinoma are a poor prognostic indicator. The appearance of multiple skin metastases with other internal metastases shorten the survival time.

  18. Effects of locus coeruleus stimulation on the responses of SI neurons of the rat to controlled natural and electrical stimulation of the skin.

    PubMed

    Snow, P J; Andre, P; Pompeiano, O

    1999-02-01

    1. The effects of microstimulation of the locus coeruleus (LC) region on the spontaneous discharge and the response of SI neurons to natural and electrical stimulation of the skin have been investigated in 26 urethane anesthetized Sprague-Dawley rats. In particular, one or two air puffs, 5-10 msec in duration, 1-2 psi, usually separated by an interval of 40 msec, were applied on the hairy skin of the wrist or the forepaw at the presentation rate of 1/sec. For units unresponsive to air puffs, similar presentation of low intensity electrical stimuli (0.2-5.0 V, 0.2-0.4 msec pulses) were applied through two needles inserted on the most effective area of the skin. Both natural and electrical stimulations of the skin were applied under control conditions, as well as 50 msec after a 250 msec train of 0.3 msec pulses at 40 Hz. 20-30 microA applied stereotaxically to the LC complex through a tungsten microelectrode. 2. Not all cortical units exhibited spontaneous discharge. Most of the units, however, which were spontaneously active, were inhibited by electrical stimulation of the LC complex, while the remaining ones were excited. The sites of stimulation, which included either the LC proper or the locus subcoeruleus, were identified following both anatomical and physiological criteria. 3. SI neurons recorded at sites between 400 and 950 microns below the surface of the cortex, thus being most likely granule cells of layers III and IV, responded to cutaneous stimuli with spikes which occurred with a latency of 20-30 msec in response to single air puffs and a latency of 15-20 msec in response to single electrical pulses to the skin. In both instances the response to the second stimulus applied at the interstimulus interval of 40 msec was markedly reduced or abolished due to postexcitatory inhibition following the response to the first stimulus (in-field inhibition). In contrast, units particularly located at or below 1000 microns from the cortical surface, which were of

  19. Topically applied hypericin exhibits skin penetrability on nude mice.

    PubMed

    Li, Zhuo-Heng; Li, Yuan-Yuan; Hou, Min; Yang, Tao; Lu, Lai-Chun; Xu, Xiao-Yu

    2018-06-13

    Hypericin, a powerful natural photosensitizer in photodynamic therapy (PDT), is suitable for treating skin diseases involving excess capillary proliferation. In the present study, we aimed to evaluate the skin penetrability of topically applied hypericin, expecting a reduced risk of prolonged skin photosensitivity, which often occurs after systemic administration. Firstly, the Franz diffusion cell assays were performed to evaluate the penetration effects of different enhancers, including menthol, propylene glycol, camphanone, azone, and carbamide. In view of above evaluation results, we selected menthol as the enhancer in the subsequent in vivo studies. The setting groups were as follows: the blank control group, the light-exposure control group, the gel-base control group, the hypericin gel group, and a hypericin gel-containing menthol group. Except for the blank control, all other animals were irradiated by a LED light. Then, fluorescence microscopy was performed to examine the distribution of hypericin in the skin of nude mouse. Macroscopic and microscopic analyses were also carried out to detect pathological changes in the skin after topical hypericin-PDT treatment. Immunohistochemistry was used to determine the expression change of PECAM-1. As shown in the results, menthol facilitated hypericin penetrate the skin of nude mice most. The results of in vivo assays revealed that hypericin penetrated nude mouse skin, spread to the dermis, and resulted in obvious photosensitivity reaction on the dermal capillaries. Moreover, skin injured by the photosensitive reaction induced by hypericin-PDT treatment was replaced by normal skin within 7 days. We concluded that topical applied hypericin could penetrate nude mouse skin well and has a great potential in PDT treatment of skin diseases.

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

    NASA Astrophysics Data System (ADS)

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

    2017-01-01

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

  1. Skin transcriptome reveals the intrinsic molecular mechanisms underlying hair follicle cycling in Cashmere goats under natural and shortened photoperiod conditions.

    PubMed

    Yang, Min; Song, Shen; Dong, Kunzhe; Chen, XiaoFei; Liu, Xuexue; Rouzi, Marhaba; Zhao, Qianjun; He, Xiaohong; Pu, Yabin; Guan, Weijun; Ma, Yuehui; Jiang, Lin

    2017-10-18

    The growth of cashmere exhibits a seasonal pattern arising from photoperiod change. However, the underlying molecular mechanism remains unclear. We profiled the skin transcriptome of six goats at seven time points during hair follicle cycling via RNA-seq. The six goats comprised three goats exposed to a natural photoperiod and three exposed to a shortened photoperiod. During hair cycle transition, 1713 genes showed differential expression, and 332 genes showed a pattern of periodic expression. Moreover, a short photoperiod induced the hair follicle to enter anagen early, and 246 genes overlapped with the periodic genes. Among these key genes, cold-shock domain containing C2 (CSDC2) was highly expressed in the epidermis and dermis of Cashmere goat skin, although its function in hair-follicle development remains unknown. CSDC2 silencing in mouse fibroblasts resulted in the decreased mRNA expression of two key hair-follicle factors, leading to reduced cell numbers and a lower cell density. Cashmere growth or molting might be controlled by a set of periodic regulatory genes. The appropriate management of short light exposure can induce hair follicles to enter full anagen early through the activation of these regulators. The CSDC2 gene is a potentially important transcription factor in the hair growth cycle.

  2. Occupational skin cancer induced by ultraviolet radiation and its prevention.

    PubMed

    Diepgen, T L; Fartasch, M; Drexler, H; Schmitt, J

    2012-08-01

    Skin cancer is by far the most common kind of cancer diagnosed in many western countries and ultraviolet radiation is the most important risk factor for cutaneous squamous cell carcinoma (SCC) and basal cell carcinoma (BCC). Although employees at several workplaces are exposed to increased levels of UV radiation, skin cancer due to long-term intense occupational exposure to UV radiation is often not considered as occupational disease. The actually available evidence in the epidemiological literature clearly indicates that occupational UV radiation exposure is a substantial and robust risk factor for the development of cutaneous SCC and also clearly shows a significant risk for developing BCC. There is enough scientific evidence that outdoor workers have an increased risk of developing work-related occupational skin cancer due to natural UV radiation exposure and adequate prevention strategies must be implemented. The three measures which are successful and of particular importance in the prevention of nonmelanoma skin cancer in outdoor workers are changes in behaviour regarding awareness of health and disease resulting from exposure to natural UV radiation, protection from direct UV radiation by wearing suitable clothing, and regular and correct use of appropriate sunscreens. © 2012 The Authors. BJD © 2012 British Association of Dermatologists.

  3. [Adsorption of the TiO2 @ yeast composite microspheres for adsorbing Fluorescent Whitening Agent-VBL in fixed bed].

    PubMed

    Wu, Fei; Zhang, Kai-Qiang; Bai, Bo; Wang, Hong-Lun; Suo, You-Rui

    2015-02-01

    In this work, the adsorption potential of TiO2@ yeast composite microspheres to remove Fluorescent Whitening Agent-VBL (FWA-VBL) from aqueous solution was investigated using fixed-bed adsorption column. The effects of pH(2.0-8.0), bed height (1-3 cm), inlet concentration (20-80 mg x L(-1)) and feed flow rate (5-11 mL x min(-1)) on the breakthrough characteristics of the adsorption system were determined. The results showed that the highest bed capacity of 223.80 mg x g(-1) was obtained under the condition of pH 2.0, 80 mg x L(-1) inlet dye concentration, 1.0 cm bed height and 5 mL x min(-1) flow rate. The adsorption data were fitted to three well-established fixed-bed adsorption models, namely, BDST model, Thomas model and Yoon-Nelson model. The results fitted well to the three models with coefficients of correlation R2 > 0.980 in different conditions. The TiO2 @ yeast composite microspheres have desired regeneration ability and could be reused for four times.

  4. AVS-1357 inhibits melanogenesis via prolonged ERK activation.

    PubMed

    Kim, Dong-Seok; Lee, Hyun-Kyung; Park, Seo-Hyoung; Chae, Chong Hak; Park, Kyoung-Chan

    2009-08-01

    In this study, we demonstrated that a derivative of imidazole, AVS-1357, is a novel skin-whitening compound. AVS-1357 was found to significantly inhibit melanin production in a dose-dependent manner; however, it did not directly inhibit tyrosinase. Furthermore, we found that AVS-1357 induced prolonged activation of extracellular signal-regulated kinase (ERK) and Akt, while it downregulated microphthalmia-associated transcription factor (MITF) and tyrosinase. It has been reported that the activation of ERK and/or Akt is involved in melanogenesis. Therefore, we examined the effects of AVS-1357 on melanogenesis in the absence or presence of PD98059 (a specific inhibitor of the ERK pathway) and/or LY294002 (a specific inhibitor of the Akt pathway). PD98059 dramatically increased melanogenesis, whereas LY294002 had no effect. Furthermore, PD98059 attenuated AVS-1357 induced ERK activation, as well as the downregulation of MITF and tyrosinase. These findings suggest that the effects of AVS-1357 occur via downregulation of MITF and tyrosinase, which is caused by AVS-1357-induced prolonged ERK activation. Taken together, our results indicate that AVS-1357 has the potential as a new skin whitening agent.

  5. Effect of traditional plants in Sri Lanka on skin fibroblast cell number.

    PubMed

    Sano, Katsura; Someya, Takao; Hara, Kotaro; Sagane, Yoshimasa; Watanabe, Toshihiro; Wijesekara, R G S

    2018-08-01

    This article describes the effects of extracts of several plants collected in Sri Lanka on the cell number of human skin fibroblasts. This study especially focuses on the plants traditionally used in indigenous systems of medicine in Sri Lanka, such as Ayurveda, as described below (English name, "local name in Sri Lanka," scientific name). Bougainvillea plant, "bouganvilla," Bougainvillea grabla (Nature׳s Beauty Creations Ltd., 2014) [1], purple fruited pea eggplant,"welthibbatu," Solanum trilobatum (Nature׳s Beauty Creations Ltd., 2014) [2], country borage plant, "kapparawalliya," Plectranthus amboinicus  (Nature׳s Beauty Creations Ltd., 2014) [3], malabar nut plant, "adhatoda," Justicia adhatoda (Nature׳s Beauty Creations Ltd., 2014) [4], long pepper plant,"thippili," Piper longum (Nature׳s Beauty Creations Ltd., 2014) [5], holy basil plant, "maduruthala," Ocimum tenuiflorum (Nature׳s Beauty Creations Ltd., 2014) [6], air plant, "akkapana," Kalanchoe pinnata (Nature׳s Beauty Creations Ltd., 2014) [7], plumed cockscomb plant, "kiri-henda," Celosia argentea (Nature׳s Beauty Creations Ltd., 2014) [8], neem plant,"kohomba," Azadirachta indica (Nature׳s Beauty Creations Ltd., 2014) [9], emblic myrobalan plant, "nelli," Phyllanthus emblica (Nature׳s Beauty Creations Ltd., 2014) [10]. Human skin fibroblast cells were treated with various concentration of plant extracts (0-3.0%), and the cell viability of cells were detected using calcein assay. The cell viabillity profiles are provided as line graphs.

  6. Characterization of oily mature skin by biophysical and skin imaging techniques.

    PubMed

    de Melo, M O; Maia Campos, P M B G

    2018-02-13

    The skin is a complex biological system and may suffer change according to the environmental factors, as higher temperatures can increase sebum excretion, presenting oiliness and acne. These alterations can persist during the aging and provoke more changes in aged skin. In this study we evaluated the mature oily skin characteristics using biophysical and skin imaging techniques. Sixty healthy female subjects, aged between 39 and 55 years old were recruited and separated into 2 groups according to their skin type: normal/dry and oily skin. The skin was evaluated in terms of stratum corneum water content, transepidermal water loss (TEWL) sebum content, dermis thickness and echogenicity, skin microrelief, and pores content. The mature oily skin presented no significant differences when compared to the normal/dry skin on the stratum corneum water content and TEWL parameters. The sebum content was significantly higher on the oily skin group. The microrelief analysis showed an increase of skin roughness values in the oily skin and increase of scaliness in the normal/dry skin. The oily skin showed lower dermis echogenicity mainly in the frontal region and higher dermis thickness when compared to normal/dry skin. The mature oily skin showed different characteristics from normal/dry skin in terms of sebum content, microrelief parameters, and dermis thickness. This way, the characterization of mature oily skin in an objective way is very important to development of dermocosmetic products for more effective treatments focused specially on this type of skin. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Exploring the potential of using algae in cosmetics.

    PubMed

    Wang, Hui-Min David; Chen, Ching-Chun; Huynh, Pauline; Chang, Jo-Shu

    2015-05-01

    The applications of microalgae in cosmetic products have recently received more attention in the treatment of skin problems, such as aging, tanning and pigment disorders. There are also potential uses in the areas of anti-aging, skin-whitening, and pigmentation reduction products. While algae species have already been used in some cosmetic formulations, such as moisturizing and thickening agents, algae remain largely untapped as an asset in this industry due to an apparent lack of utility as a primary active ingredient. This review article focuses on integrating studies on algae pertinent to skin health and beauty, with the purpose of identifying serviceable algae functions in practical cosmetic uses. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Simplifying Skin Disease Diagnosis with Topical Nanotechnology.

    PubMed

    Yeo, David C; Xu, Chenjie

    2018-05-01

    A new study published in the journal Nature Biomedical Engineering 1 documents a novel diagnostic technology that exploits topically applied nanotechnology to detect skin tissue biomarkers for diagnosis. This concept is demonstrated by noninvasively imaging connective tissue growth factor (CTGF) mRNA in abnormal scar cells, whole tissue, and animal models. In this commentary, we highlight the main findings and discuss their implications. Successful implementation in the clinic could give rise to self-applied, biopsy-free diagnostic technology and significantly reduce healthcare burden. Crucially, noninvasive visualization of disease biomarkers, mobile device signal acquisition, and Internet-enabled transmission could significantly transform the diagnosis of skin disease and other superficial tissues.

  9. Skin protection efficacy from UV irradiation and skin penetration property of polysaccharide-benzophenone conjugates as a sunscreen agent.

    PubMed

    Heo, Sukyoung; Hwang, Hee Sook; Jeong, Yohan; Na, Kun

    2018-09-01

    Sunscreen materials have been developed to protect skin from UV radiation. However, many organic sunscreen materials are small molecules and absorbed into human skin after topical application and lead to systemic side effects. To improve the adverse effects of conventional sunscreen materials, we designed a sunscreen agent using an organic sunscreen material and a polymer. Dioxybenzone, an organic sunscreen compound is selected and polymerized with natural polymer pullulan. Polymerization not only provides a long polymer backbone to dioxybenzone, but also keeps the distance between benzene rings of the dioxybenzone and prevents reduction of photoabsorption intensity. UV/vis spectrophotometry confirmed that dioxybenzone-pullulan polymer (DOB-PUL) and dioxybenzone (DOB) demonstrated similar UV absorption. To measure the accumulation of sunscreen materials on skin, Franz diffusion cell was used to confirm the accumulation of DOB and lack of penetration of DOB-PUL. Most importantly, DOB showed higher plasma concentration after multiple applications compared to that of DOB-PUL. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. 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 ...

  11. Effectiveness of an employee skin cancer screening program for secondary prevention.

    PubMed

    Uslu, Ugur; Hees, Felix; Winnik, Eva; Uter, Wolfgang; Sticherling, Michael

    2016-08-01

    Incidences of UV-induced skin cancer are continuously increasing. For this reason, early diagnosis is becoming more important. In this study, 783 employees of a technical company participated in an employee skin cancer screening program, which consisted of a physical examination for benign and malignant skin lesions and premalignant conditions. To ensure the quality of the examinations, screening was only performed by 5 trained dermatologists. Participants also were asked to complete a standardized questionnaire prior to examination. A total of 661 skin lesions were diagnosed among 48% of participants; 12.8% of participants exhibited 50 or more melanocytic nevi and the risk for developing skin cancer was categorized as at least moderate for 64.9%. Additionally, 84.4% of participants with at least 1 skin lesion were advised to have a checkup within 1 year. The high rate of suspicious nevi detected in this study suggested that employee skin cancer screening programs are effective and also should be recommended at companies where employees are not at increased risk for developing skin cancer due to the nature of their work (eg, those who work outdoors). Despite the comparatively selective and young study population, these examinations provide evidence of the importance of skin cancer screening for the wider population.

  12. A novel bioactive chalcone of Morus australis inhibits tyrosinase activity and melanin biosynthesis in B16 melanoma cells.

    PubMed

    Takahashi, Makoto; Takara, Kensaku; Toyozato, Tomonao; Wada, Koji

    2012-01-01

    The methanol extract of Morus australis (shimaguwa) acts as a whitening agent due to the inhibition of tyrosinase activity. In order to explore the mechanism(s) of the whitening action, constituents of the 95% methanol extract from the dried stems of shimaguwa were isolated and their skin-whitening capacity was examined. Bioassay-guided fractionation of the methanol soluble extract of shimaguwa led to the isolation of 2, 4, 2', 4'-hydroxycalcone (chalcone 1) and three analogues of chalcone 1 with 3'-substituted resorcinol moieties (chalcones 2-4). Chalcone derivative 4 proved to be a novel compound and was fully characterized. Chalcones 1-4 were evaluated for inhibition activity on mushroom tyrosinase using L-tyrosine as the substrate. The parent chalcone 1 was a highly effective inhibitor of tyrosinase activity (IC₅₀ = 0.21 μM) compared to arbutin (IC₅₀ = 164 μM). Compared to chalcone 1, chalcones 2 and 3, which possess 3'-substituted isoprenyl or bulky 2-benzoylbiphenyl, showed significantly decreased tyrosinase activity, while chalcone 4, possessing 3'-substituted 2-hydroxy-1-pentene group, showed slightly increased activity.The effects of chalcones 1-4 on melanin synthesis, without affecting cell growth, were assayed in melanin-producing B16 murine melanoma cells. Chalcone 3 significantly reduced cell viability before reaching the IC₅₀ value for melanin synthesis. In contrast, the inhibitory effects of chalcones 1, 2 and 4 were more than 100-fold greater than that of arbutin, with little or no cytotoxicity. More significantly, chalcone 2, which exhibited less tyrosinase inhibitory activity compared to the parent chalcone 1, showed the highest inhibition of melanin synthesis in B16 cells among the chalcones tested. Accordingly, chalcones 1 and 2, and the novel chalcone 4 might be the active components responsible for the whitening ability of shimaguwa. Moreover, whitening ability was not exclusively due to tyrosinase inhibition.

  13. 19 CFR 12.63 - Seal-skin or sea-otter-skin waste.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 1 2014-04-01 2014-04-01 false Seal-skin or sea-otter-skin waste. 12.63 Section... OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Fur-Seal Or Sea-Otter Skins § 12.63 Seal-skin or sea-otter-skin waste. Seal-skin or sea-otter-skin waste composed of small pieces not large enough to be...

  14. 19 CFR 12.63 - Seal-skin or sea-otter-skin waste.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 1 2013-04-01 2013-04-01 false Seal-skin or sea-otter-skin waste. 12.63 Section... OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Fur-Seal Or Sea-Otter Skins § 12.63 Seal-skin or sea-otter-skin waste. Seal-skin or sea-otter-skin waste composed of small pieces not large enough to be...

  15. 19 CFR 12.63 - Seal-skin or sea-otter-skin waste.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Seal-skin or sea-otter-skin waste. 12.63 Section... OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Fur-Seal Or Sea-Otter Skins § 12.63 Seal-skin or sea-otter-skin waste. Seal-skin or sea-otter-skin waste composed of small pieces not large enough to be...

  16. 19 CFR 12.63 - Seal-skin or sea-otter-skin waste.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 1 2011-04-01 2011-04-01 false Seal-skin or sea-otter-skin waste. 12.63 Section... OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Fur-Seal Or Sea-Otter Skins § 12.63 Seal-skin or sea-otter-skin waste. Seal-skin or sea-otter-skin waste composed of small pieces not large enough to be...

  17. 19 CFR 12.63 - Seal-skin or sea-otter-skin waste.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Seal-skin or sea-otter-skin waste. 12.63 Section... OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Fur-Seal Or Sea-Otter Skins § 12.63 Seal-skin or sea-otter-skin waste. Seal-skin or sea-otter-skin waste composed of small pieces not large enough to be...

  18. Disinfection of human skin allografts in tissue banking: a systematic review report.

    PubMed

    Johnston, C; Callum, J; Mohr, J; Duong, A; Garibaldi, A; Simunovic, N; Ayeni, O R

    2016-12-01

    The use of skin allografts to temporarily replace lost or damaged skin is practiced worldwide. Naturally occurring contamination can be present on skin or can be introduced at recovery or during processing. This contamination can pose a threat to allograft recipients. Bacterial culture and disinfection of allografts are mandated, but the specific practices and methodologies are not dictated by standards. A systematic review of literature from three databases found 12 research articles that evaluated bioburden reduction processes of skin grafts. The use of broad spectrum antibiotics and antifungal agents was the most frequently identified disinfection method reported demonstrating reductions in contamination rates. It was determined that the greatest reduction in the skin allograft contamination rates utilized 0.1 % peracetic acid or 25 kGy of gamma irradiation at lower temperatures.

  19. Matching the skin barrier to the skin type.

    PubMed

    Thompson, Hyacinth; North, Jacqui; Davenport, Rebecca; Williams, Julia

    Peristomal skin problems are thought to be common (Herlufsson et al, 2006; Williams et al, 2010), and can interfere with the security of stoma products. Stoma patients are reliant on the integrity of their peristomal skin to maintain a normal lifestyle. Bekkers et al (1996) highlighted that, if the peristomal skin becomes damaged, it not only affects the person physically, but also psychologically, ultimately prolonging rehabilitation and adaptation to the stoma. Therefore, it can be concluded that maintaining skin integrity is a basic and essential skill in ensuring good stoma management. This article explores the assessment of four stoma patients, highlighting the importance of matching their skin type with their skin barrier for optimum skin protection. The patients have kindly agreed for their case studies to be published as a means of informing others. All names have been changed in line with Nursing and Midwifery Council (2010) guidelines to maintain patient confidentiality. This article was originally presented at the World Council of Enterostomal Therapists' (WCET) annual conference in 2010, receiving first prize at poster presentations.

  20. 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.

  1. Evaluation of a 6% hydrogen peroxide tooth whitening gel on enamel and dentine microhardness in vitro.

    PubMed

    Joiner, Andrew; Thakker, Gopal; Cooper, Yvonne

    2004-01-01

    The aims of this study were to evaluate the effects of a novel 6% hydrogen peroxide containing tooth whitener, Xtra White (XW), on enamel and dentine microhardness in vitro. Polished human enamel and dentine specimens were prepared and baseline microhardness determined. In study 1, enamel specimens were exposed to 20 min cycles of either water, XW or Sprite Light for up to 28 cycles. In studies 2 and 3, enamel specimens were treated with 20 min cycles of either XW or water and exposed to whole saliva at all other times. In study 3, an additional exposure to a fluoride containing toothpaste was conducted. In total, 28 treatments were conducted in order to simulate a 2 weeks product use. In study 4, dentine specimens were treated as per study 3. Final microhardness measurements were taken and for studies 3 and 4 colour measurements were additionally taken. XW and water gave no statistically significant (p>0.05) changes in enamel and dentine microhardness after 28 treatments. Sprite Light gave a significant (p<0.00002) reduction in enamel microhardness after one 20 min treatment. XW showed significant bleaching of enamel and dentine specimens as compared to the water control. XW does not have any significant effect on enamel and dentine microhardness.

  2. Communicating the location of potential skin neoplasms for excision between the referring and the operating doctor--an audit of skin lesion referrals in Whanganui, New Zealand.

    PubMed

    Welsh, Fraser; Bullen, Naomi; Aiono, Semisi

    2013-08-30

    The importance of correctly defining the location of potential skin cancer when surgical treatment may be required is self-evident. Clear communication is essential if the professional diagnosing potential skin cancer is not the same professional providing treatment. We aimed to assess the nature of the localising information provided in referrals to the local anaesthetic skin lesion theatre in our institution. Information localising target lesions for new patients seen in our local anaesthetic skin excision theatre was recorded during a 2-month period April to May 2012 inclusive 100 patients were seen in our skin excision theatre during the study period; 16 patients were not able to identify the target skin lesion at the time they entered the operating theatre. The target lesion could not be determined from the referral text in 30/100 cases. Diagrams were provided in 19/100 cases. Photographs were provided in 3/100 cases. Pictorial and photographic means of communicating the location of suspicious lesions are under-utilised in our service. Relying on the patient or the referral text to correctly identify the lesion leaves considerable room for error. We suggest that photographic information for skin lesion referrals is adopted as a minimum standard.

  3. Formulation and Evaluation of Exotic Fat Based Cosmeceuticals for Skin Repair

    PubMed Central

    Mandawgade, S. D.; Patravale, Vandana B.

    2008-01-01

    Mango butter was explored as a functional, natural supplement and active skin ingredient in skin care formulations. A foot care cream was developed with mango butter to evaluate its medicinal value and protective function in skin repair. Qualitative comparison and clinical case studies of the product were carried out. Wound healing potential of foot care cream was investigated on the rat excision and incision wound models. Results of the clinical studies demonstrated complete repair of worn and cracked skin in all the human volunteers. Furthermore, foot care cream exhibited significant healing response in both the wound models. The project work could be concluded as establishment of high potential for mango butter to yield excellent emolliency for better skin protection. Improving the product features and medicinal functionality further validate mango butter as a specialty excipient in development of cosmeceuticals and has an immense value for its commercialization. PMID:20046792

  4. Of Soap and Seborrhea: Skin Problems in Infants

    PubMed Central

    Nickerson, Granville

    1972-01-01

    Skin lesions in infants can herald serious internal problems or be relatively benign. Interpreting skin manifestations can be extremely confusing, therefore, and although many can be ‘spot’ diagnoses, puzzling rashes should be approached systematically according to the areas that are affected and the nature of the lesions. Dr. Nickerson describes common dermatological conditions seen in the newborn and older infants and advocates a common sense approach, especially on questions of what to bathe the baby with. He outlines followup procedures for those conditions which are signs of more serious internal disorders, and emphasizes reassurance and education of the mother. PMID:20468758

  5. Wave propagation as a marker of structural and topographic properties of human skin

    NASA Astrophysics Data System (ADS)

    Djaghloul, M.; Abdouni, A.; Thieulin, C.; Zahouani, H.

    2018-06-01

    Chronological skin ageing is a phenomenon which imposes structural and functional changes on the cutaneous tissue. Mechanically, these changes can be related to structural rearrangements of the cutaneous tissue on surface and in volume (layers thickness). At the micro-structural level, the constitutional elements of the skin, collagen and elastin fibres, undergo also this rearrangement. The evolution of skin’s mechanical properties at this level is the origin of a primordial in-vivo mechanical characteristic known as the natural pretension. In the context of understanding the in-vivo skin mechanical behaviour, related to the natural pretension, a lot of instrumentations have been demonstrated in the literature. They are mainly based on the interaction between dynamic adapted solicitation and the observed reaction on the skin. In this study, we evaluate the mechanical behaviour of human skin, following an impact which induces wave propagation. The use of impact solicitation allows the direct correlation between the dynamic induced reaction (vibration, and wave propagation) of the cutaneous tissue and its mechanical property. In our development, impact solicitation is contactless, with an air blast as generator of local deformation. The estimation of the speed of wave propagation enables the characterization of the mechanical behaviour of the skin. In order to validate the developed approaches, to understand the chronological ageing, gender and anisotropy effects on the skin properties, measurements have been realized on 77 healthy volunteers separated in five age groups. The obtained results are consistent with earlier works and confirm the efficiency of the developed instrumentation to estimate the changes of mechanical behaviour of the skin under age and gender effects.

  6. Wind tunnel study of natural ventilation of building integrated photovoltaics double skin façade

    NASA Astrophysics Data System (ADS)

    Hudişteanu, Sebastian Valeriu; Popovici, Cătălin George; Cherecheş, Nelu-Cristian

    2018-02-01

    The paper presents a wind tunnel experimental analysis of a small-scale building model (1:30). The objective of the study is to determine the wind influence on the ventilation of a double skin façade channel (DSF) and the cooling effect over integrated photovoltaic panels. The tests were achieved by conceiving and implementation of an experimental program using a wind tunnel with atmospheric boundary layer. The effect of the wind over the ventilation of the horizontal channels of double skin façades is evaluated for different incident velocities. The results are generalized for the average steady state values of the velocities analysed. The experimental results put in evidence the correlation between the reference wind velocity and the dynamics of the air movement inside the double skin façade. These values are used to determine the convective heat transfer and the cooling effect of the air streams inside the channel upon the integrated photovoltaic panels. The decrease of the photovoltaic panels temperature determines a raise of 11% in efficiency and power generated.

  7. Withaferin A suppresses the up-regulation of acetyl-coA carboxylase 1 and skin tumor formation in a skin carcinogenesis mouse model.

    PubMed

    Li, Wenjuan; Zhang, Chunjing; Du, Hongyan; Huang, Vincent; Sun, Brandi; Harris, John P; Richardson, Quitin; Shen, Xinggui; Jin, Rong; Li, Guohong; Kevil, Christopher G; Gu, Xin; Shi, Runhua; Zhao, Yunfeng

    2016-11-01

    Withaferin A (WA), a natural product derived from Withania somnifera, has been used in traditional oriental medicines to treat neurological disorders. Recent studies have demonstrated that this compound may have a potential for cancer treatment and a clinical trial has been launched to test WA in treating melanoma. Herein, WA's chemopreventive potential was tested in a chemically-induced skin carcinogenesis mouse model. Pathological examinations revealed that WA significantly suppressed skin tumor formation. Morphological observations of the skin tissues suggest that WA suppressed cell proliferation rather than inducing apoptosis during skin carcinogenesis. Antibody Micro array analysis demonstrated that WA blocked carcinogen-induced up-regulation of acetyl-CoA carboxylase 1 (ACC1), which was further confirmed in a skin cell transformation model. Overexpression of ACC1 promoted whereas knockdown of ACC1 suppressed anchorage-independent growth and oncogene activation of transformable skin cells. Further studies demonstrated that WA inhibited tumor promotor-induced ACC1 gene transcription by suppressing the activation of activator protein 1. In melanoma cells, WA was also able to suppress the expression levels of ACC1. Finally, results using human skin cancer tissues confirmed the up-regulation of ACC1 in tumors than adjacent normal tissues. In summary, our results suggest that withaferin A may have a potential in chemoprevention and ACC1 may serve as a critical target of WA. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  8. Discovery of Repellents from Natural Products

    USDA-ARS?s Scientific Manuscript database

    Natural products are an ideal source of chemicals for topical application to human skin, and can be a means of personal protection from the bites of mosquitoes and other arthropods. This report covers a diverse array of natural compounds, and includes descriptions of observed correlations between ch...

  9. [Study on objectively evaluating skin aging according to areas of skin texture].

    PubMed

    Shan, Gaixin; Gan, Ping; He, Ling; Sun, Lu; Li, Qiannan; Jiang, Zheng; He, Xiangqian

    2015-02-01

    Skin aging principles play important roles in skin disease diagnosis, the evaluation of skin cosmetic effect, forensic identification and age identification in sports competition, etc. This paper proposes a new method to evaluate the skin aging objectively and quantitatively by skin texture area. Firstly, the enlarged skin image was acquired. Then, the skin texture image was segmented by using the iterative threshold method, and the skin ridge image was extracted according to the watershed algorithm. Finally, the skin ridge areas of the skin texture were extracted. The experiment data showed that the average areas of skin ridges, of both men and women, had a good correlation with age (the correlation coefficient r of male was 0.938, and the correlation coefficient r of female was 0.922), and skin texture area and age regression curve showed that the skin texture area increased with age. Therefore, it is effective to evaluate skin aging objectively by the new method presented in this paper.

  10. Laser speckle and skin cancer: skin roughness assessment

    NASA Astrophysics Data System (ADS)

    Lee, Tim K.; Tchvialeva, Lioudmila; Zeng, Haishan; McLean, David I.; Lui, Harvey

    2009-10-01

    Incidence of skin cancer has been increasing rapidly since the last few decades. Non-invasive optical diagnostic tools may improve the diagnostic accuracy. In this paper, skin structure, skin cancer statistics and subtypes of skin cancer are briefly reviewed. Among the subtypes, malignant melanoma is the most aggressive and dangerous; early detection dramatically improves the prognosis. Therefore, a non-invasive diagnostic tool for malignant melanoma is especially needed. In addition, in order for the diagnostic tool to be useful, it must be able to differentiate melanoma from common skin conditions such as seborrheic keratosis, a benign skin disease that resembles melanoma according to the well known clinical-assessment ABCD rule. The key diagnostic feature between these two diseases is surface roughness. Based on laser speckle contrast, our research team has recently developed a portable, optical, non-invasive, in-vivo diagnostic device for quantifying skin surface roughness. The methodology of our technique is described in details. Examining the preliminary data collected in a pilot clinical study for the prototype, we found that there was a difference in roughness between melanoma and seborrheic keratosis. In fact, there was a perfect cutoff value for the two diseases based on our initial data.

  11. Multiple rare opportunistic and pathogenic fungi in persistent foot skin infection.

    PubMed

    Chan, Giek Far; Sinniah, Sivaranjini; Idris, Tengku Idzzan Nadzirah Tengku; Puad, Mohamad Safwan Ahmad; Abd Rahman, Ahmad Zuhairi

    2013-03-01

    Persistent superficial skin infection caused by multiple fungi is rarely reported. Recently, a number of fungi, both opportunistic and persistent in nature were isolated from the foot skin of a 24-year old male in Malaysia. The fungi were identified as Candida parapsilosis, Rhodotorula mucilaginosa, Phoma spp., Debaryomyces hansenii, Acremonium spp., Aureobasidium pullulans and Aspergillus spp., This is the first report on these opportunistic strains were co-isolated from a healthy individual who suffered from persistent foot skin infection which was diagnosed as athlete's foot for more than 12 years. Among the isolated fungi, C. parapsilosis has been an increasingly common cause of skin infections. R. mucilaginosa and D. hansenii were rarely reported in cases of skin infection. A. pullulans, an emerging fungal pathogen was also being isolated in this case. Interestingly, it was noted that C. parapsilosis, R. mucilaginosa, D. hansenii and A. pullulans are among the common halophiles and this suggests the association of halotolerant fungi in causing persistent superficial skin infection. This discovery will shed light on future research to explore on effective treatment for inhibition of pathogenic halophiles as well as to understand the interaction of multiple fungi in the progress of skin infection.

  12. 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.

  13. The Potential of Plant Phenolics in Prevention and Therapy of Skin Disorders

    PubMed Central

    Działo, Magdalena; Mierziak, Justyna; Korzun, Urszula; Preisner, Marta; Szopa, Jan; Kulma, Anna

    2016-01-01

    Phenolic compounds constitute a group of secondary metabolites which have important functions in plants. Besides the beneficial effects on the plant host, phenolic metabolites (polyphenols) exhibit a series of biological properties that influence the human in a health-promoting manner. Evidence suggests that people can benefit from plant phenolics obtained either by the diet or through skin application, because they can alleviate symptoms and inhibit the development of various skin disorders. Due to their natural origin and low toxicity, phenolic compounds are a promising tool in eliminating the causes and effects of skin aging, skin diseases, and skin damage, including wounds and burns. Polyphenols also act protectively and help prevent or attenuate the progression of certain skin disorders, both embarrassing minor problems (e.g., wrinkles, acne) or serious, potentially life-threatening diseases such as cancer. This paper reviews the latest reports on the potential therapy of skin disorders through treatment with phenolic compounds, considering mostly a single specific compound or a combination of compounds in a plant extract. PMID:26901191

  14. The Potential of Plant Phenolics in Prevention and Therapy of Skin Disorders.

    PubMed

    Działo, Magdalena; Mierziak, Justyna; Korzun, Urszula; Preisner, Marta; Szopa, Jan; Kulma, Anna

    2016-02-18

    Phenolic compounds constitute a group of secondary metabolites which have important functions in plants. Besides the beneficial effects on the plant host, phenolic metabolites (polyphenols) exhibit a series of biological properties that influence the human in a health-promoting manner. Evidence suggests that people can benefit from plant phenolics obtained either by the diet or through skin application, because they can alleviate symptoms and inhibit the development of various skin disorders. Due to their natural origin and low toxicity, phenolic compounds are a promising tool in eliminating the causes and effects of skin aging, skin diseases, and skin damage, including wounds and burns. Polyphenols also act protectively and help prevent or attenuate the progression of certain skin disorders, both embarrassing minor problems (e.g., wrinkles, acne) or serious, potentially life-threatening diseases such as cancer. This paper reviews the latest reports on the potential therapy of skin disorders through treatment with phenolic compounds, considering mostly a single specific compound or a combination of compounds in a plant extract.

  15. 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.

  16. Glycerol and urea can be used to increase skin permeability in reduced hydration conditions.

    PubMed

    Björklund, Sebastian; Engblom, Johan; Thuresson, Krister; Sparr, Emma

    2013-12-18

    The natural moisturizing factor (NMF) is a group of hygroscopic molecules that is naturally present in skin and protects from severe drying. Glycerol and urea are two examples of NMF components that are also used in skin care applications. In the present study, we investigate the influence of glycerol and urea on the permeability of a model drug (metronidazole, Mz) across excised pig skin membranes at different hydrating conditions. The degree of skin hydration is regulated by the gradient in water activity across the membrane, which in turn depends on the water activity of the formulation in contact with the skin membrane. Here, we determine the water activity of all formulations employed using an isothermal calorimetric method. Thus, the gradient in water activity is controlled by a novel experimental set-up with well-defined boundary conditions on both sides of the skin membrane. The results demonstrate that glycerol and urea can retain high steady state flux of Mz across skin membranes at dehydrating conditions, which otherwise would decrease the permeability due to dehydration. X-ray diffraction measurements are performed to give insight into the effects of glycerol and urea on SC molecular organization. The novel steady state flux results can be related to the observation that water, glycerol, and urea all affect the structural features of the SC molecular components in a similar manner. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  17. Dual Infection and Superinfection Inhibition of Epithelial Skin Cells by Two Alphaherpesviruses Co-Occur in the Natural Host

    PubMed Central

    Jarosinski, Keith W.

    2012-01-01

    Hosts can be infected with multiple herpesviruses, known as superinfection; however, superinfection of cells is rare due to the phenomenon known as superinfection inhibition. It is believed that dual infection of cells occurs in nature, based on studies examining genetic exchange between homologous alphaherpesviruses in the host, but to date, this has not been directly shown in a natural model. In this report, gallid herpesvirus 2 (GaHV-2), better known as Marek’s disease virus (MDV), was used in its natural host, the chicken, to determine whether two homologous alphaherpesviruses can infect the same cells in vivo. MDV shares close similarities with the human alphaherpesvirus, varicella zoster virus (VZV), with respect to replication in the skin and exit from the host. Recombinant MDVs were generated that express either the enhanced GFP (eGFP) or monomeric RFP (mRFP) fused to the UL47 (VP13/14) herpesvirus tegument protein. These viruses exhibited no alteration in pathogenic potential and expressed abundant UL47-eGFP or -mRFP in feather follicle epithelial cells in vivo. Using laser scanning confocal microscopy, it was evident that these two similar, but distinguishable, viruses were able to replicate within the same cells of their natural host. Evidence of superinfection inhibition was also observed. These results have important implications for two reasons. First, these results show that during natural infection, both dual infection of cells and superinfection inhibition can co-occur at the cellular level. Secondly, vaccination against MDV with homologous alphaherpesvirus like attenuated GaHV-2, or non-oncogenic GaHV-3 or meleagrid herpesvirus (MeHV-1) has driven the virus to greater virulence and these results implicate the potential for genetic exchange between homologous avian alphaherpesviruses that could drive increased virulence. Because the live attenuated varicella vaccine is currently being administered to children, who in turn could be superinfected

  18. Alteration of Dentin-Enamel Mechanical Properties Due to Dental Whitening Treatments

    PubMed Central

    Zimmerman, B.; Datko, L.; Cupelli, M.; Alapati, S.; Dean, D.; Kennedy, M.

    2010-01-01

    The mechanical properties of dentin and enamel affect the reliability and wear properties of a tooth. This study investigated the influence of clinical dental treatments and procedures, such as whitening treatments or etching prior to restorative procedures. Both autoclaved and non-autoclaved teeth were studied in order to allow for both comparison with published values and improved clinical relevance. Nanoindentation analysis with the Oliver-Pharr model provided elastic modulus and hardness across the dentin-enamel junction (DEJ). Large increases were observed in the elastic modulus of enamel in teeth that had been autoclaved (52.0GPa versus 113.4GPa), while smaller increases were observed in the dentin (17.9GPa versus 27.9GPa). Likewise, there was an increase in the hardness of enamel (2.0GPa versus 4.3GPa) and dentin (0.5GPa versus 0.7GPa) with autoclaving. These changes suggested that the range of elastic modulus and hardness values previously reported in literature may be partially due to the sterilization procedures. Treatment of the exterior of non-autoclaved teeth with Crest Whitestrips™, Opalescence™ or UltraEtch™ caused changes in the mechanical properties of both the enamel and dentin. Those treated with Crest Whitestrips™ showed a reduction in the elastic modulus of enamel (55.3GPa to 32.7GPa) and increase in the elastic modulus of dentin (17.2GPa to 24.3GPa). Opalescence™ treatments did not significantly affect the enamel properties, but did result in a decrease in modulus of dentin (18.5GPa to 15.1GPa). Additionally, as expected, UltraEtch™ treatment decreased the modulus and hardness of enamel (48.7GPa to 38.0GPa and 1.9GPa to 1.5GPa, respectively) and dentin (21.4GPa to 15.0GPa and 1.9GPa to 1.5GPa, respectively). Changes in the mechanical properties were linked to altered protein concentration within the tooth, as evidenced by fluorescence microscopy and Fourier transform infrared spectroscopy. PMID:20346902

  19. Alteration of dentin-enamel mechanical properties due to dental whitening treatments.

    PubMed

    Zimmerman, B; Datko, L; Cupelli, M; Alapati, S; Dean, D; Kennedy, M

    2010-05-01

    The mechanical properties of dentin and enamel affect the reliability and wear properties of a tooth. This study investigated the influence of clinical dental treatments and procedures, such as whitening treatments or etching prior to restorative procedures. Both autoclaved and non-autoclaved teeth were studied in order to allow for both comparison with published values and improved clinical relevance. Nanoindentation analysis with the Oliver-Pharr model provided elastic modulus and hardness across the dentin-enamel junction (DEJ). Large increases were observed in the elastic modulus of enamel in teeth that had been autoclaved (52.0 GPa versus 113.4 GPa), while smaller increases were observed in the dentin (17.9 GPa versus 27.9 GPa). Likewise, there was an increase in the hardness of enamel (2.0 GPa versus 4.3 GPa) and dentin (0.5 GPa versus 0.7 GPa) with autoclaving. These changes suggested that the range of elastic modulus and hardness values previously reported in the literature may be partially due to the sterilization procedures. Treatment of the exterior of non-autoclaved teeth with Crest Whitestrips, Opalescence or UltraEtch caused changes in the mechanical properties of both the enamel and dentin. Those treated with Crest Whitestrips showed a reduction in the elastic modulus of enamel (55.3 GPa to 32.7 GPa) and increase in the elastic modulus of dentin (17.2 GPa to 24.3 GPa). Opalescence treatments did not significantly affect the enamel properties, but did result in a decrease in the modulus of dentin (18.5 GPa to 15.1 GPa). Additionally, as expected, UltraEtch treatment decreased the modulus and hardness of enamel (48.7 GPa to 38.0 GPa and 1.9 GPa to 1.5 GPa, respectively) and dentin (21.4 GPa to 15.0 GPa and 1.9 GPa to 1.5 GPa, respectively). Changes in the mechanical properties were linked to altered protein concentration within the tooth, as evidenced by fluorescence microscopy and Fourier transform infrared spectroscopy. Published by Elsevier Ltd.

  20. Dynamic Skin Patterns in Cephalopods

    PubMed Central

    How, Martin J.; Norman, Mark D.; Finn, Julian; Chung, Wen-Sung; Marshall, N. Justin

    2017-01-01

    Cephalopods are unrivaled in the natural world in their ability to alter their visual appearance. These mollusks have evolved a complex system of dermal units under neural, hormonal, and muscular control to produce an astonishing variety of body patterns. With parallels to the pixels on a television screen, cephalopod chromatophores can be coordinated to produce dramatic, dynamic, and rhythmic displays, defined collectively here as “dynamic patterns.” This study examines the nature, context, and potential functions of dynamic patterns across diverse cephalopod taxa. Examples are presented for 21 species, including 11 previously unreported in the scientific literature. These range from simple flashing or flickering patterns, to highly complex passing wave patterns involving multiple skin fields. PMID:28674500

  1. Formulation design for topical drug and nanoparticle treatment of skin disease.

    PubMed

    Raphael, Anthony P; Garrastazu, Gabriela; Sonvico, Fabio; Prow, Tarl W

    2015-02-01

    The skin has evolved to resist the penetration of foreign substances and particles. Topical therapeutic and cosmeceutical delivery is a growing field founded on selectively overcoming this barrier. Both the biology of the skin and the nature of the formulation/active ingredient must be aligned for efficient transcutaneous delivery. This review discusses the biological changes in the skin barrier that occur with common dermatological conditions. This context is the foundation for the discussion of formulation strategies to improve penetration profiles of common active ingredients in dermatology. Finally, we compare and contrast those approaches to recent advances described in the research literature with an eye toward the future of topical formulation design.

  2. Is skin penetration a determining factor in skin sensitization ...

    EPA Pesticide Factsheets

    Summary:Background. It is widely accepted that substances that cannot penetrate through the skin will not be sensitisers. Thresholds based on relevant physicochemical parameters such as a LogKow > 1 and a MW 1 is a true requirement for sensitisation.Methods. A large dataset of substances that had been evaluated for their skin sensitisation potential, together with measured LogKow values was compiled from the REACH database. The incidence of skin sensitisers relative to non-skin sensitisers below and above the LogKow = 1 threshold was evaluated. Results. 1482 substances with associated skin sensitisation outcomes and measured LogKow values were identified. 305 substances had a measured LogKow < 0 and of those, 38 were sensitisers.Conclusions. There was no significant difference in the incidence of skin sensitisation above and below the LogKow = 1 threshold. Reaction chemistry considerations could explain the skin sensitisation observed for the 38 sensitisers with a LogKow < 0. The LogKow threshold is a self-evident truth borne out from the widespread misconception that the ability to efficiently penetrate the stratum corneum is a key determinant of skin sensitisation potential and potency. Using the REACH data extracted to test out the validity of common assumptions in the skin sensitization AOP. Builds on trying to develop a proof of concept IATA

  3. Analyses of volatile organic compounds from human skin

    PubMed Central

    Gallagher, M.; Wysocki, C.J.; Leyden, J.J.; Spielman, A.I.; Sun, X.; Preti, G.

    2008-01-01

    Summary Background Human skin emits a variety of volatile metabolites, many of them odorous. Much previous work has focused upon chemical structure and biogenesis of metabolites produced in the axillae (underarms), which are a primary source of human body odour. Nonaxillary skin also harbours volatile metabolites, possibly with different biological origins than axillary odorants. Objectives To take inventory of the volatile organic compounds (VOCs) from the upper back and forearm skin, and assess their relative quantitative variation across 25 healthy subjects. Methods Two complementary sampling techniques were used to obtain comprehensive VOC profiles, viz., solid-phase micro extraction and solvent extraction. Analyses were performed using both gas chromatography/mass spectrometry and gas chromatography with flame photometric detection. Results Nearly 100 compounds were identified, some of which varied with age. The VOC profiles of the upper back and forearm within a subject were, for the most part, similar, although there were notable differences. Conclusions The natural variation in nonaxillary skin odorants described in this study provides a baseline of compounds we have identified from both endogenous and exogenous sources. Although complex, the profiles of volatile constituents suggest that the two body locations share a considerable number of compounds, but both quantitative and qualitative differences are present. In addition, quantitative changes due to ageing are also present. These data may provide future investigators of skin VOCs with a baseline against which any abnormalities can be viewed in searching for biomarkers of skin diseases. PMID:18637798

  4. New insights into HIV-1-primary skin disorders

    PubMed Central

    2011-01-01

    Since the first reports of AIDS, skin involvement has become a burdensome stigma for seropositive patients and a challenging task for dermatologist and infectious disease specialists due to the severe and recalcitrant nature of the conditions. Dermatologic manifestations in AIDS patients act as markers of disease progression, a fact that enhances the importance of understanding their pathogenesis. Broadly, cutaneous disorders associated with HIV type-1 infection can be classified as primary and secondary. While the pathogenesis of secondary complications, such as opportunistic infections and skin tumours, is directly correlated with a decline in the CD4+ T cell count, the origin of the certain manifestations primarily associated with the retroviral infection itself still remains under investigation. The focus of this review is to highlight the immunological phenomena that occur in the skin of HIV-1-seropositive patients, which ultimately lead to skin disorders, such as seborrhoeic dermatitis, atopic dermatitis, psoriasis and eosinophilic folliculitis. Furthermore, we compile the latest data on how shifts in the cytokines milieu, impairments of the innate immune compartment, reactions to xenobiotics and autoimmunity are causative agents in HIV-1-driven skin diseases. Additionally, we provide a thorough analysis of the small animal models currently used to study HIV-1-associated skin complications, centering on transgenic rodent models, which unfortunately, have not been able to fully unveil the role of HIV-1 genes in the pathogenesis of their primarily associated dermatological manifestations. PMID:21261982

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

    PubMed

    Shimizu, Rana; Nonomura, Yoshimune

    2018-01-01

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

  6. 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 ...

  7. Skin Diseases: Skin and Sun—Not a good mix

    MedlinePlus

    ... Current Issue Past Issues Skin Diseases Skin and Sun —Not a good mix Past Issues / Fall 2008 ... turn Javascript on. Good skin care begins with sun safety. Whether it is something as simple as ...

  8. Specificity of the Tuberculin Skin Test Is Modified by Use of a Protein Cocktail Containing ESAT-6 and CFP-10 in Cattle Naturally Infected with Mycobacterium bovis

    PubMed Central

    Flores-Villalva, S.; Suárez-Güemes, F.; Espitia, C.; Whelan, A. O.; Vordermeier, M.

    2012-01-01

    The mycobacterial immunodominant ESAT-6 and CFP-10 antigens are strongly recognizable in tuberculosis-infected cattle, and they do not elicit a response in cattle without infection. In addition, they are absent in most environmental mycobacterial species, and therefore, their use can be an alternative to purified protein derivative (PPD) tuberculin in the development of a more specific skin diagnostic test in cattle. The aim of the current study was to assess the potential of an ESAT-6 and CFP-10 (E6-C10) protein cocktail in a skin test format in naturally tuberculosis-infected and paratuberculosis-infected cattle. We also included MPB83 as a third component in one of the protein cocktail preparations. The protein cocktail was tested at different dose concentrations (5, 10, and 15 μg per protein). The best skin response to the E6-C10 protein cocktail was obtained with 10 μg. Subsequently, this concentration was tested in 2 herds with high and low bovine tuberculosis prevalence, the latter with paratuberculosis coinfection. Our data show that the E6-C10 cocktail allows identification of an important proportion of animals that PPDB is not able to recognize, especially in low-prevalence herds. The protein cocktail did not induce reactions in tuberculosis-free cattle or in paratuberculosis-infected cattle. Addition of MPB83 to the protein cocktail did not make any difference in the skin reaction. PMID:22419675

  9. Specificity of the tuberculin skin test is modified by use of a protein cocktail containing ESAT-6 and CFP-10 in cattle naturally infected with Mycobacterium bovis.

    PubMed

    Flores-Villalva, S; Suárez-Güemes, F; Espitia, C; Whelan, A O; Vordermeier, M; Gutiérrez-Pabello, J A

    2012-05-01

    The mycobacterial immunodominant ESAT-6 and CFP-10 antigens are strongly recognizable in tuberculosis-infected cattle, and they do not elicit a response in cattle without infection. In addition, they are absent in most environmental mycobacterial species, and therefore, their use can be an alternative to purified protein derivative (PPD) tuberculin in the development of a more specific skin diagnostic test in cattle. The aim of the current study was to assess the potential of an ESAT-6 and CFP-10 (E6-C10) protein cocktail in a skin test format in naturally tuberculosis-infected and paratuberculosis-infected cattle. We also included MPB83 as a third component in one of the protein cocktail preparations. The protein cocktail was tested at different dose concentrations (5, 10, and 15 μg per protein). The best skin response to the E6-C10 protein cocktail was obtained with 10 μg. Subsequently, this concentration was tested in 2 herds with high and low bovine tuberculosis prevalence, the latter with paratuberculosis coinfection. Our data show that the E6-C10 cocktail allows identification of an important proportion of animals that PPDB is not able to recognize, especially in low-prevalence herds. The protein cocktail did not induce reactions in tuberculosis-free cattle or in paratuberculosis-infected cattle. Addition of MPB83 to the protein cocktail did not make any difference in the skin reaction.

  10. 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

  11. The investigation of the skin characteristics of males focusing on gender differences, skin perception, and skin care habits.

    PubMed

    Mizukoshi, Koji; Akamatsu, Hisashi

    2013-05-01

    Various studies have examined the properties of male skin. However, because these studies mostly involved simple measurement with non-invasive devices, a lack of understanding of the properties of male skin remains. In this study, we focused and investigated not only on simple instrumental measurements but also on gender differences and men's subjective perceptions of skin and daily skin care habits. Barrier function depends on corneocyte maturation level as well as sebum amount. Irrespective of the skin type, a high percentage of male subjects perceived a 'tacky feeling'. However, the percentage of men perceiving a 'shiny feeling' differed by skin type. Furthermore, there was a relationship between skin care habits and skin function. Men who did not perform a daily skincare regimen demonstrated a significantly higher sebum amount and transepidermal water loss value than those who did perform a daily skincare regimen. The results of this study indicate that male skin has two specific characteristics: impaired barrier function because of the excess amount of sebum and a lack of an appropriate skin care regimen because of the 'tacky feeling' caused by excess sebum. © 2012 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

  12. A preliminary study of differentially expressed genes in expanded skin and normal skin: implications for adult skin regeneration.

    PubMed

    Yang, Mei; Liang, Yimin; Sheng, Lingling; Shen, Guoxiong; Liu, Kai; Gu, Bin; Meng, Fanjun; Li, Qingfeng

    2011-03-01

    In adults, severely damaged skin heals by scar formation and cannot regenerate to the original skin structure. However, tissue expansion is an exception, as normal skin regenerates under the mechanical stretch resulting from tissue expansion. This technique has been used clinically for defect repair and organ reconstruction for decades. However, the phenomenon of adult skin regeneration during tissue expansion has caused little attention, and the mechanism of skin regeneration during tissue expansion has not been fully understood. In this study, microarray analysis was performed on expanded human skin and normal human skin. Significant difference was observed in 77 genes, which suggest a network of several integrated cascades, including cytokines, extracellular, cytoskeletal, transmembrane molecular systems, ion or ion channels, protein kinases and transcriptional systems, is involved in the skin regeneration during expansion. Among these, the significant expression of some regeneration related genes, such as HOXA5, HOXB2 and AP1, was the first report in tissue expansion. Data in this study suggest a list of candidate genes, which may help to elucidate the fundamental mechanism of skin regeneration during tissue expansion and which may have implications for postnatal skin regeneration and therapeutic interventions in wound healing.

  13. Is lack of sleep capable of inducing DNA damage in aged skin?

    PubMed

    Kahan, V; Ribeiro, D A; Egydio, F; Barros, L A; Tomimori, J; Tufik, S; Andersen, M L

    2014-01-01

    Skin naturally changes with age, becoming more fragile. Various stimuli can alter skin integrity. The aim of this study was to evaluate whether sleep deprivation affects the integrity of DNA in skin and exacerbates the effects of aging. Fifteen-month old female Hairless mice underwent 72 h of paradoxical sleep deprivation or 15 days of chronic sleep restriction. Punch biopsies of the skin were taken to evaluate DNA damage by single cell gel (comet) assay. Neither paradoxical sleep deprivation nor sleep restriction increased genetic damage, measured by tail movement and tail intensity values. Taken together, the findings are consistent with the notion that aging overrides the effect of sleep loss on the genetic damage in elderly mice. © 2014 S. Karger AG, Basel.

  14. Fractional Skin Harvesting: Autologous Skin Grafting without Donor-site Morbidity

    PubMed Central

    Wang, Ying; Farinelli, William A.; Jiménez-Lozano, Joel; Franco, Walfre; Sakamoto, Fernanda H.; Cheung, Evelyn J.; Purschke, Martin; Doukas, Apostolos G.; Anderson, R. Rox

    2013-01-01

    Background: Conventional autologous skin grafts are associated with significant donor-site morbidity. This study was conducted to determine feasibility, safety, and efficacy of a new strategy for skin grafting based on harvesting small columns of full-thickness skin with minimal donor-site morbidity. Methods: The swine model was used for this study. Hundreds of full-thickness columns of skin tissue (~700 µm diameter) were harvested using a custom-made harvesting device, and then applied directly to excisional skin wounds. Healing in donor and graft sites was evaluated over 3 months by digital photographic measurement of wound size and blinded, computer-aided evaluation of histological features and compared with control wounds that healed by secondary intention or with conventional split-thickness skin grafts (STSG). Results: After harvesting hundreds of skin columns, the donor sites healed rapidly without scarring. These sites reepithelialized within days and were grossly and histologically indistinguishable from normal skin within 7 weeks. By contrast, STSG donor sites required 2 weeks for reepithelialization and retained scar-like characteristics in epidermal and dermal architecture throughout the experiment. Wounds grafted with skin columns resulted in accelerated reepithelialization compared with ungrafted wounds while avoiding the “fish-net” patterning caused by STSG. Conclusion: Full-thickness columns of skin can be harvested in large quantities with negligible long-term donor-site morbidity, and these columns can be applied directly to skin wounds to enhance wound healing. PMID:25289241

  15. 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, ...

  16. Hand hygiene and skin health.

    PubMed

    Kownatzki, E

    2003-12-01

    The high rate of hand problems associated with the hand hygiene of medical professions is due to a combination of damaging factors: (1) the removal of barrier lipids by detergent cleaning and alcohol antisepsis followed by a loss of moisturizers and stratum corneum water and (2) the overhydration of the stratum corneum by sweat trapped within gloves. Together the facilitate the invasion of irritants and allergens which elicit inflammatory responses in the dermis. Among the lipids and water-soluble substances removed are natural antibacterials. Their loss leads to increased growth of transient and pathogenic micro-organisms which jeapordizes the very intention of skin hygiene. The kinetics of damage and its repair, and epidemiological evidence suggest that modern synthetic detergents as used in foaming liquid cleansers are the major offender. Conversely, the replacement of detergents with non-detergent emulsion cleansers has been shown to be effective in reducing the prevalence of hand problems among hospital staff. Presently recommended hand antisepsis reduces the risks to patients, but puts the burden on the health care provider. Rather than fighting micro-organisms at the expense of the skin's health, the skin and its own defences should be considered a collaborator in combating infectious diseases.

  17. Mechanisms of Drying of Skin Forming Materials

    NASA Astrophysics Data System (ADS)

    Hassan, Haydar Mahmood

    appeared on the droplet at a certain stage of the drying process under any drying conditions. As the drying temperature was increased the resistance of the skin to mass transfer increased. The drying rate history of any material depended upon the nature of the skin formed which, in turn, depended upon the drying conditions. A mathematical model was proposed for the drying of the first type of skin-forming material. This was based on the assumption that, once all the granules gelatinised at the gelatinisation temperature, a skin appeared instantaneously on the droplet surface. The experimentally-observed times at which the skin appeared on the droplets surfaces were in excellent agreement with those predicted from the model. The work should assist in understanding the fundamentals of particulate drying processes, particularly when skin -formation occurs and may be a crucial factor in volatiles retention.

  18. 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 ...

  19. [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.

  20. Morphogenesis and Biomechanics of Engineered Skin Cultured Under Uniaxial Strain.

    PubMed

    Blackstone, Britani N; Powell, Heather M

    2012-04-01

    Split-thickness autograft is the standard wound treatment for full-thickness burns. In large burns, sparse availability of uninjured skin prevents rapid closure of the wound, resulting in increased scar tissue formation or mortality. Tissue-engineered skin (ES) offers promise when autografts are not available. ES, constructed from a polymeric scaffold and skin cells, has been shown to reduce donor site area required to permanently close wounds, mortality, and morbidity from scarring but cannot restore all skin functions. Current generations of ES are orders of magnitude weaker than normal human skin, leading to difficulty in surgical application, greater susceptibility to mechanical damage during fabrication and application, and less elasticity and strength once engrafted. Previous studies to improve ES biomechanics focus on altering the scaffolding material, which resulted in modest improvements but often inhibited proper skin development. As the skin is naturally under static strain, adding these mechanical cues to the culture environment is hypothesized to improve ES biomechanics. ES was cultured under applied static strains ranging from 0% to 40% strain for a total of 10 days. Strain magnitudes of 10% and 20% strain resulted in significantly stronger ES than unstrained controls, showed upregulation of many genes encoding structural extracellular matrix proteins, and exhibited increased epidermal cell proliferation and differentiation. Enhanced biomechanical properties of ES can allow for facile surgical application and less damage during dressing changes. These findings suggest that mechanical cues play a significant role in skin development and should be further explored.

  1. Ultrasonography of Skin Changes in Legs with Chronic Venous Disease.

    PubMed

    Caggiati, A

    2016-10-01

    In daily practice, ultrasonography (US) is used only to designate the location and pattern of venous lesions. Skin US is not performed between routine venous investigations. Skin morphology is evaluated by the same probes used for routine Duplex evaluation of superficial veins. US findings from evident skin lesions are comparatively evaluated with those from the surrounding apparently normal skin and from the contralateral leg. Inflammation and dermal edema can be found in the apparently normal skin of C2 legs. Swollen legs show thickening of the subcutaneous layer as a result of diffuse soaking or anechoic cavities, with or without dermal edema. Chronic hypodermitis is characterized by inflammatory edema in initial phases, and by liposclerosis in advanced cases. Recrudescence of inflammation provokes focal rarefactions of the subcutaneous layer, possibly related to ulcer opening. In legs with venous disorders, sonography refines clinical evaluation of the skin and may reveal changes not highlighted by inspection. Some of these changes could require further investigation because they have not yet been explained or described. Skin sonography should improve knowledge of the natural history of skin changes, as well as contribute to a better grading of venous diseases severity In particular, US evidence of cutaneous and subcutaneous changes in C2 legs should be considered to stratify the treatment in C2 legs, by identifying those in which varicose veins are not simply a cosmetic problem. Copyright © 2016 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  2. Myricetin, a potent natural agent for treatment of diabetic skin damage by modulating TIMP/MMPs balance and oxidative stress

    PubMed Central

    2016-01-01

    Foot ulceration is a major cause of morbidity in patients with diabetes, and abnormal peripheral neuropathy often results in hospitalization. Up-regulation of matrix metalloproteinases and down-regulation of tissue inhibitor of metalloproteinase 1 are noted to be distinctive biological functions of diabetic dermal fibroblasts. The aim of this study was to evaluate the biological effects of modified retinoids on diabetic fibroblasts. Myricetin, a natural compound, balances the TIMP1/MMP ratio and oxidative stress in diabetic fibroblasts. Our results indicate that myricetin significantly ameliorates the effects of diabetes on dermal fibroblasts. In addition, we found that the oxidative stress imbalance induced by a high glucose concentration plays an important role in the changes to dermal fibroblasts that occur in diabetes. Our findings support the hypothesis that myricetin has the potential to repair faulty skin function arising from diabetes. PMID:27765936

  3. Pilot trials with a fluorescent whitening agent of the bis(triazoly) stilbene-disulfonic acid type in golden orfes.

    PubMed

    Hamburger, B; Maul, W; Patzschke, K; Theidel, H; Wegner, L A

    1975-01-01

    Golden orfes were examined for uptake, distribution, and elimination of radioactivity administered in the form of a 14C-labelled fluorescent whitening agent (FWA) of the bis(triazolyl)stilbenedisulfonic acid type. Results of these studies are given below. Pilot trials using FWA concentrations of 10 and 100 ppb and a population density of 1 fish per liter show that an equilibrium between uptake and elimination of the FWA develops in the animals within a period of one week; i.e., the incorporated traces of the FWA are not irreversibly bound. The radioactivity is mainly located in the gall bladder and in the intestinal contents, as well as in the liver, throat, and gills. The muscular system (filet) is virtually free from activity. Approximately 1-2% of the FWA amount administered per animal (corresponding to the concentration factors of 7-14) can be temporarily detected in the fish. Radioactivity is eliminated comparatively quickly. Two days following the transfer of the fish into water free from FWA a concentration factor as low as 1 is reached, i.e. from this time the FWA concentration in the animals decreases to less than 10 resp. 100 ppb.

  4. Critical review of Ayurvedic Varṇya herbs and their tyrosinase inhibition effect

    PubMed Central

    Sharma, Khemchand; Joshi, Namrata; Goyal, Chinky

    2015-01-01

    Introduction: The aspiration for light skin (fair complexion) is becoming pronounced in a greater number of people in the present times with natural products being more in demand than their synthetic counterparts. Research in the area of skin-lightening agents is an expanding field with the knowledge being updated regularly. In Ayurveda, varṇya, raktaprasādana, tvacya are few terms specifying skin lightening with respect to its modern counterpart i.e., Tyrosinase inhibition, the most commonly reported method of skin lightening. Aim: The present review is undertaken for screening twenty herbs from Varṇya Mahākaṣāya, Lodhrādi varṇya gaṇa, Elādi varṇa prasādana gaṇa and few varṇya formulations to evaluate their probable modes of action through which the skin lightening is effected as per both Ayurveda and biomedical concepts. Materials and Methods: Critical review of herbs to show varṇya property is compiled from various Ayurvedic texts as well as from multiple articles on the internet to justify their skin lightening property on the basis of data collected. Result and Conclusion: All the twenty herbs reviewed are found to act as varṇya directly (citation as varṇya) or indirectly (alleviation of pitta and rakta) as per Ayurveda and to interfere in melanogenesis pathway through tyrosinase inhibition as per biomedicine. This shows their potential to act as good skin whitening agents. Śuṇṭhi being a part of many varṇya formulations, is the only herb among all reviewed in the present study found to exhibit tyrosinase inhibition without any Ayurvedic citation of varṇya property. PMID:26600663

  5. On skin expansion.

    PubMed

    Pamplona, Djenane C; Velloso, Raquel Q; Radwanski, Henrique N

    2014-01-01

    This article discusses skin expansion without considering cellular growth of the skin. An in vivo analysis was carried out that involved expansion at three different sites on one patient, allowing for the observation of the relaxation process. Those measurements were used to characterize the human skin of the thorax during the surgical process of skin expansion. A comparison between the in vivo results and the numerical finite elements model of the expansion was used to identify the material elastic parameters of the skin of the thorax of that patient. Delfino's constitutive equation was chosen to model the in vivo results. The skin is considered to be an isotropic, homogeneous, hyperelastic, and incompressible membrane. When the skin is extended, such as with expanders, the collagen fibers are also extended and cause stiffening in the skin, which results in increasing resistance to expansion or further stretching. We observed this phenomenon as an increase in the parameters as subsequent expansions continued. The number and shape of the skin expanders used in expansions were also studied, both mathematically and experimentally. The choice of the site where the expansion should be performed is discussed to enlighten problems that can lead to frustrated skin expansions. These results are very encouraging and provide insight into our understanding of the behavior of stretched skin by expansion. To our knowledge, this study has provided results that considerably improve our understanding of the behavior of human skin under expansion. Copyright © 2013 Elsevier Ltd. All rights reserved.

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

    PubMed

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

    2015-09-01

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

  7. Skin deep: Coverage of skin cancer and recreational tanning in Canadian women's magazines (2000-2012).

    PubMed

    McWhirter, Jennifer E; Hoffman-Goetz, Laurie

    2015-06-18

    Skin cancer is a significant public health problem among Canadians. Knowledge and attitudes about health are informed by mass media. The aim of our study was to describe the volume and nature of coverage of skin cancer and recreational tanning in Canadian women's magazines. Directed content analysis on article text and images in six popular Canadian women's magazines (Chatelaine, Canadian Living, Homemakers, Flare, FASHION, ELLE Canada) from 2000-2012 with attention to risk factors, ultraviolet radiation (UV) exposure and protection behaviours, and early detection. Six popular American women's magazines were used for a between-country comparison. There were 154 articles (221 images) about skin cancer and tanning published over 13 years. Volume of coverage did not increase in a linear fashion over time. The most common risk factor reported on was UV exposure (39%), with other risk factors less frequently identified. Although 72% of articles promoted sunscreen use, little content encouraged other protection behaviours. Only 15% of articles and 1% of images discouraged indoor tanning, while 41% of articles and 53% of images promoted the tanned look as attractive. Few articles (<11%) reported on early detection. Relative to American magazines, Canadian magazines had a greater proportion of content that encouraged sunscreen use and promoted the tanned look and a lesser proportion of content on risk factors and early detection. Skin cancer and tanning messages in Canadian women's magazines had a narrow focus and provided limited information on risk factors or screening. Conflicting messages about prevention (text vs. images) may contribute to harmful UV behaviours among Canadian women.

  8. Effect of skin wettedness on sweat gland response

    NASA Technical Reports Server (NTRS)

    Nadel, E. R.; Stolwijk, J. A. J.

    1973-01-01

    Investigation of the effect of skin wettedness upon sweating rate. Several techniques were used to gain a better understanding of the quantitative nature of this effect. The results include the finding that the evaporative power of the environment has a profound effect on the relationship between body temperature and sweating rate.

  9. Amperometric monitoring of quercetin permeation through skin membranes.

    PubMed

    Rembiesa, Jadwiga; Gari, Hala; Engblom, Johan; Ruzgas, Tautgirdas

    2015-12-30

    Transdermal delivery of quercetin (QR, 3,3',4',5,7-pentahydroxyflavone), a natural flavonoid with a considerable antioxidant capacity, is important for medical treatment of, e.g., skin disorders. QR permeability through skin is low, which, at the same time, makes the monitoring of percutaneous QR penetration difficult. The objective of this study was to assess an electrochemical method for monitoring QR penetration through skin membranes. An electrode was covered with the membrane, exposed to QR solution, and electrode current was measured. The registered current was due to electro-oxidation of QR penetrating the membrane. Exploiting strict current-QR flux relationships diffusion coefficient, D, of QR in skin and dialysis membranes was calculated. The D values were strongly dependent on the theoretical model and parameters assumed in the processing of the amperometric data. The highest values of D were in the range of 1.6-6.1×10(-7)cm(2)/s. This was reached only for skin membranes pretreated with buffer-ethanol mixture for more than 24h. QR solutions containing penetration enhancers, ethanol and l-menthol, definitely increased D values. The results demonstrate that electrochemical setup gives a possibility to assess penetration characteristics as well as enables monitoring of penetration dynamics, which is more difficult by traditional methods using Franz cells. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Why people seek advice from community pharmacies about skin problems.

    PubMed

    Tucker, Rod; Stewart, Derek

    2015-04-01

    The objective of this study was to explore the reasons why patients with undiagnosed skin problems seek advice at pharmacies. Semi-structured telephone interviews were conducted with patients presenting at pharmacies requesting advice for their own (or their child's) undiagnosed skin problem. Twenty-five patients were interviewed. Key themes around choice of pharmacy were convenience of professional advice, triage to general practitioner (GP) care if warranted, inaccessibility of GP care and perceived non-serious nature of the condition. Interviewees also described high levels of trust in their pharmacists. Few concerns were noted, but those that were centred on lack of privacy and the potential for misdiagnosis. Almost all participants felt positive about their pharmacy care and would re-visit for future skin problems. Patients with undiagnosed skin problems seek advice from pharmacies for reasons of professional advice, accessibility, familiarity and trust and because they perceive their conditions as non-serious. © 2014 Royal Pharmaceutical Society.

  11. Photodecomposition and Phototoxicity of Natural Retinoids

    PubMed Central

    Tolleson, William H.; Cherng, Shui-Hui; Xia, Qingsu; Boudreau, Mary; Yin, Jun Jie; Wamer, Wayne G.; Howard, Paul C.; Yu, Hongtao; Fu, Peter P.

    2005-01-01

    Sunlight is a known human carcinogen. Many cosmetics contain retinoid-based compounds, such as retinyl palmitate (RP), either to protect the skin or to stimulate skin responses that will correct skin damaged by sunlight. However, little is known about the photodecomposition of some retinoids and the toxicity of these retinoids and their sunlight-induced photodecomposition products on skin. Thus, studies are required to test whether topical application of retinoids enhances the phototoxicity and photocarcinogenicity of sunlight and UV light. Mechanistic studies are needed to provide insight into the disposition of retinoids in vitro and on the skin, and to test thoroughly whether genotoxic damage by UV-induced radicals may participate in any toxicity of topically applied retinoids in the presence of UV light. This paper reports the update information and our experimental results on photostability, photoreactions, and phototoxicity of the natural retinoids including retinol (ROH), retinal, retinoid acid (RA), retinyl acetate, and RP (Figure 1). PMID:16705812

  12. The importance of optical methods for non-invasive measurements in the skin care industry

    NASA Astrophysics Data System (ADS)

    Stamatas, Georgios N.

    2010-02-01

    Pharmaceutical and cosmetic industries are concerned with treating skin disease, as well as maintaining and promoting skin health. They are dealing with a unique tissue that defines our body in space. As such, skin provides not only the natural boundary with the environment inhibiting body dehydration as well as penetration of exogenous aggressors to the body, it is also ideally situated for optical measurements. A plurality of spectroscopic and imaging methods is being used to understand skin physiology and pathology and document the effects of topically applied products on the skin. The obvious advantage of such methods over traditional biopsy techniques is the ability to measure the cutaneous tissue in vivo and non-invasively. In this work, we will review such applications of various spectroscopy and imaging methods in skin research that is of interest the cosmetic and pharmaceutical industry. Examples will be given on the importance of optical techniques in acquiring new insights about acne pathogenesis and infant skin development.

  13. The Effect of Particles on Electrolytically Polymerized Thin Natural MCF Rubber for Soft Sensors Installed in Artificial Skin.

    PubMed

    Shimada, Kunio; Mochizuki, Osamu; Kubota, Yoshihiro

    2017-04-19

    The aim of this study is to investigate the effect of particles as filler in soft rubber sensors installed in artificial skin. We examine sensors made of natural rubber (NR-latex) that include magnetic particles of Ni and Fe₃O₄ using magnetic compound fluid (MCF). The 1-mm thickness of the electrolytically polymerized MCF rubber makes production of comparatively thin rubber sensors feasible. We first investigate the effect of magnetic particles Ni and Fe₃O₄ on the curing of MCF rubber. Next, in order to adjust the electric properties of the MCF rubber, we adopt Al₂O₃ dielectric particles. We investigate the effect of Al₂O₃ particles on changes in electric current, voltage and temperature of electrolytically polymerized MCF rubber liquid, and on the electric properties under the application of normal and shear forces. By adjusting the ratio of Ni, Fe₃O₄, Al₂O₃ and water in MCF rubber with Al₂O₃, it is possible to change the electric properties.

  14. About Skin-to-Skin Care (Kangaroo Care)

    MedlinePlus

    ... Size Email Print Share About Skin-to-Skin Care Page Content Article Body You may be able ... care, also called kangaroo care. What is Kangaroo Care? Kangaroo care was developed in South America as ...

  15. Protective effects of skin permeable epidermal and fibroblast growth factor against ultraviolet-induced skin damage and human skin wrinkles.

    PubMed

    An, Jae Jin; Eum, Won Sik; Kwon, Hyuck Se; Koh, Jae Sook; Lee, Soo Yun; Baek, Ji Hwoon; Cho, Yong-Jun; Kim, Dae Won; Han, Kyu Huyng; Park, Jinseu; Jang, Sang Ho; Choi, Soo Young

    2013-12-01

    Epidermal and fibroblast growth factor (EGF and FGF1) proteins play an important role in the regeneration and proliferation of skin cells. EGF and FGF1 have considerable potential as possible therapeutic or cosmetic agents for the treatment of skin damage including wrinkles. Using protein transduction domains (PTD), we investigated whether PTD-EGF and FGF1 transduced into skin cells and tissue. Transduced proteins showed protective effects in a UV-induced skin damage model as well as against skin wrinkles. Transduced PTD-EGF and FGF1 proteins were detected by immunofluorescence and immunohistochemistry. The effects of PTD-EGF and FGF1 were examined by WST assay, Western blotting, immunohistochemistry, and skin wrinkle parameters. The PTD-EGF and FGF1 increased cell proliferation and collagen type 1 alpha 1 protein accumulation in skin tissue. Also, PTD-EGF and FGF1 inhibited UV-induced skin damage. Furthermore, topical application of PTD-EGF and FGF1 contained ampoules which were considered to improve the wrinkle parameters of human skin. These results show that PTD-EGF and FGF1 can be a potential therapeutic or cosmetic agent for skin damaged and injury including wrinkles and aging. © 2013 Wiley Periodicals, Inc.

  16. Sensitive skin in Europe.

    PubMed

    Misery, L; Boussetta, S; Nocera, T; Perez-Cullell, N; Taieb, C

    2009-04-01

    Sensitive skin appears as a very frequent condition, but there is no comparative data between countries. To perform an epidemiological approach to skin sensitivity in different European countries. An opinion poll was conducted in eight European countries: Belgium, France, Germany, Greece, Italy, Portugal, Spain and Switzerland. This sample (4506 persons) was drawn from a representative sample of each population aged 15 years or older. Sensitive or very sensitive skin was declared by 38.4% and slightly or not sensitive skin by 61.6%. Women declared more sensitive skin than men. A dermatological disease was declared by 31.2% of people with very sensitive skin, 17.6% of those with sensitive skin, 8.7% of those with slightly sensitive skin and 3.7% of those who do not have sensitive skin. A history of childhood atopic dermatitis was more frequent in patients with sensitive or very sensitive skin. The interviewees who declared that they had dry or oily skin also reported significantly more frequently sensitive or very sensitive skin than those with normal skin. Sensitive and very sensitive skins were clearly more frequent in Italy and France. This study is the first study that compares skin sensitivity in European countries. Prevalence is high, but significant differences are noted between these countries. Dermatological antecedents (or treatments?) could be involved in the occurrence of skin sensitivity.

  17. Infrared spectroscopic measurement of skin hydration and sebum levels and comparison to corneometer and sebumeter

    NASA Astrophysics Data System (ADS)

    Ezerskaia, Anna; Pereira, S. F.; Urbach, H. P.; Varghese, Babu

    2016-05-01

    Skin health characterized by a system of water and lipids in Stratum Corneum provide protection from harmful external elements and prevent trans-epidermal water loss. Skin hydration (moisture) and sebum (skin surface lipids) are considered to be important factors in skin health; a right balance between these components is an indication of skin health and plays a central role in protecting and preserving skin integrity. In this manuscript we present an infrared spectroscopic method for simultaneous and quantitative measurement of skin hydration and sebum levels utilizing differential detection with three wavelengths 1720, 1750, and 1770 nm, corresponding to the lipid vibrational bands that lie "in between" the prominent water absorption bands. The skin sebum and hydration values on the forehead under natural conditions and its variations to external stimuli were measured using our experimental set-up. The experimental results obtained with the optical set-up show good correlation with the results obtained with the commercially available instruments Corneometer and Sebumeter.

  18. Variscan deformation along the Teisseyre-Tornquist Zone in SE Poland: Thick-skinned structural inheritance or thin-skinned thrusting?

    NASA Astrophysics Data System (ADS)

    Krzywiec, P.; Gągała, Ł.; Mazur, S.; Słonka, Ł.; Kufrasa, M.; Malinowski, M.; Pietsch, K.; Golonka, J.

    2017-10-01

    Recently acquired seismic reflection data provide better insight in the structural style of extensive sedimentary series overlying the SW slope of the East European Craton (EEC) in Poland. The two main seismic datasets - the POLCRUST-01 profile and PolandSPAN survey - yielded contrasting thick - and thin-skinned structural models for the same structural units in SE Poland. We reattempt an interpretation of the POLCRUST-01 profile using techniques of cross-section balancing and restoration aided by 2D forward seismic modelling. An outcome is the thin-skinned structural model is. This solution relies on a continuous top of the EEC crystalline basement well represented in the seismic data as well as on fragmentary, yet conclusive seismic geometries in shallow depth intervals proving the Ediacaran-Palaeozoic series to be thrust and folded. A Variscan (late Carboniferous) compressional regime is consequently invoked to explain thin-skinned structuring of the pre-Permian sedimentary pile and > 20 km of calculated shortening. We demonstrate an ambiguous nature of the top-basement irregularities previously used as indicators of basement-rooted vertical faulting. The tilt and abrupt increase of the top-basement taper under the thin-skinned belt are attributed to pre-Ordovician tectonic processes operating along the SW margin of the EEC. Post-rift subsidence and/or flexural loading giving rise to a broken foreland plate are invoked.

  19. Quantitative and simultaneous non-invasive measurement of skin hydration and sebum levels

    PubMed Central

    Ezerskaia, Anna; Pereira, S. F.; Urbach, H. Paul; Verhagen, Rieko; Varghese, Babu

    2016-01-01

    We report a method on quantitative and simultaneous non-contact in-vivo hydration and sebum measurements of the skin using an infrared optical spectroscopic set-up. The method utilizes differential detection with three wavelengths 1720, 1750, and 1770 nm, corresponding to the lipid vibrational bands that lay “in between” the prominent water absorption bands. We have used an emulsifier containing hydro- and lipophilic components to mix water and sebum in various volume fractions which was applied to the skin to mimic different oily-dry skin conditions. We also measured the skin sebum and hydration values on the forehead under natural conditions and its variations to external stimuli. Good agreement was found between our experimental results and reference values measured using conventional biophysical methods such as Corneometer and Sebumeter. PMID:27375946

  20. Evaluation of drug and sunscreen permeation via skin irradiated with UVA and UVB: comparisons of normal skin and chronologically aged skin.

    PubMed

    Hung, Chi-Feng; Fang, Chia-Lang; Al-Suwayeh, Saleh A; Yang, Shih-Yung; Fang, Jia-You

    2012-12-01

    Ultraviolet (UV) exposure is the predominant cause of skin aging. A systematic evaluation of drug skin permeation via photoaged skin is lacking. The aim of this work was to investigate whether UVA and UVB affect absorption by the skin of drugs and sunscreens, including tetracycline, quercetin, and oxybenzone. The dorsal skin of nude mice was subjected to UVA (24 and 39 J/cm(2)) or UVB (150, 200, and 250 mJ/cm(2)) irradiation. Levels of skin water loss, erythema, and sebum were evaluated, and histological examinations of COX-2 and claudin-1 expressions were carried out. Permeation of the permeants into and through the skin was determined in vitro using a Franz cell. In vivo skin uptake was also evaluated. Senescent skin (24 weeks old) was used for comparison. Wrinkling and scaling were significant signs of skin treated with UVA and UVB, respectively. The level of claudin-1, an indicator of tight junctions (TJs), was reduced by UVA and UVB irradiation. UVA enhanced tetracycline and quercetin skin deposition by 11- and 2-fold, respectively. A similar enhancement was shown for flux profiles. Surprisingly, a lower UVA dose revealed greater enhancement compared to the higher dose. The skin deposition and flux of tetracycline both decreased with UVB exposure. UVB also significantly reduced quercetin flux. The skin absorption behavior of chronologically aged skin approximated that of the UVA group, with photoaged skin showing higher enhancement. UV generally exhibited a negligible effect on modulating oxybenzone permeation. Skin disruption produced by UV does not necessarily result in enhanced skin absorption. It depends on the UV wavelength, irradiated energy, and physicochemical properties of the permeant. To the best of our knowledge, this is the first report establishing drug permeation profiles for UV-irradiated skin. Copyright © 2012 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  1. Malassezia species in healthy skin and in dermatological conditions.

    PubMed

    Prohic, Asja; Jovovic Sadikovic, Tamara; Krupalija-Fazlic, Mersiha; Kuskunovic-Vlahovljak, Suada

    2016-05-01

    The genus Malassezia comprises lipophilic species, the natural habitat of which is the skin of humans and other warm-blooded animals. However, these species have been associated with a diversity of dermatological disorders and even systemic infections. Pityriasis versicolor is the only cutaneous disease etiologically connected to Malassezia yeasts. In the other dermatoses, such as Malassezia folliculitis, seborrheic dermatitis, atopic dermatitis, and psoriasis, these yeasts have been suggested to play pathogenic roles either as direct agents of infection or as trigger factors because there is no evidence that the organisms invade the skin. Malassezia yeasts have been classified into at least 14 species, of which eight have been isolated from human skin, including Malassezia furfur, Malassezia pachydermatis, Malassezia sympodialis, Malassezia slooffiae, Malassezia globosa, Malassezia obtusa, Malassezia restricta, Malassezia dermatis, Malassezia japonica, and Malassezia yamatoensis. Distributions of Malassezia species in the healthy body and in skin diseases have been investigated using culture-based and molecular techniques, and variable results have been reported from different geographical regions. This article reviews and discusses the latest available data on the pathogenicity of Malassezia spp., their distributions in dermatological conditions and in healthy skin, discrepancies in the two methods of identification, and the susceptibility of Malassezia spp. to antifungals. © 2015 The International Society of Dermatology.

  2. Nutrition and skin.

    PubMed

    Pappas, Apostolos; Liakou, Aikaterini; Zouboulis, Christos C

    2016-09-01

    Nutrition has long been associated with skin health, including all of its possible aspects from beauty to its integrity and even the aging process. Multiple pathways within skin biology are associated with the onset and clinical course of various common skin diseases, such as acne, atopic dermatitis, aging, or even photoprotection. These conditions have been shown to be critically affected by nutritional patterns and dietary interventions where well-documented studies have demonstrated beneficial effects of essential nutrients on impaired skin structural and functional integrity and have restored skin appearance and health. Although the subject could be vast, the intention of this review is to provide the most relevant and the most well-documented information on the role of nutrition in common skin conditions and its impact on skin biology.

  3. Isolation of Resveratrol from Vitis Viniferae Caulis and Its Potent Inhibition of Human Tyrosinase

    PubMed Central

    Park, Jiaa; Boo, Yong Chool

    2013-01-01

    Tyrosinase (TYR) catalyzes rate-limiting reactions of cellular melanin synthesis, and its inhibitors are of commercial interest as potential skin whitening agents. However, the limited availability of human TYR makes the screening of TYR inhibitors difficult. To overcome this hurdle, we transformed nonmelanocytic human embryonic kidney (HEK) 293 cells to express human TYR constitutively. Using these cells as a source of human TYR, the ethanolic extracts of 52 medicinal plants grown in Korea were tested for human TYR activity, and the extract of Vitis Viniferae Caulis (dried stems of the grape tree, Vitis vinifera L.) was found to inhibit human TYR activity potently. An active compound was isolated from this extract by solvent fractionation followed by liquid column chromatography and identified as resveratrol by spectroscopic and chromatographic analyses. Resveratrol was determined to be a highly potent inhibitor of human TYR (IC50 = 0.39 μg mL−1) as compared with p-coumaric acid (IC50 = 0.66 μg mL−1) and arbutin (IC50 > 100 μg mL−1) and inhibited melanin synthesis by human epidermal melanocytes at subtoxic concentrations. This study suggests that resveratrol and resveratrol-containing extracts of Vitis Viniferae Caulis have a potential use as skin whitening agents. PMID:23476698

  4. Healthy Skin Matters

    MedlinePlus

    ... the risk of skin cancer and premature skin aging just like too much sun. In fact, most tanning beds emit mainly UVA rays, which may increase the risk of melanoma, the deadliest form of skin cancer. Physical activity Being physically active is good for your skin! It increases the ...

  5. Skin hydration, microrelief and greasiness of normal skin in Antarctica.

    PubMed

    Tsankov, N; Mateev, D; Darlenski, R

    2018-03-01

    The skin is the primary defence of the human body against external factors from physical, chemical, mechanical and biologic origin. Climatic factors together with low temperature and sun radiation affect the skin. The effect of climatic conditions in Antarctica on healthy skin has not been previously addressed. The aim of this study was to evaluate the changes in the skin hydration, greasiness and microrelief due to the extreme climatic environmental factors during the stay of the members of the Bulgarian Antarctic expedition. Fifty-nine Caucasian healthy subjects, 42 men and 17 women with mean age 50.9 years (27-68), were enrolled. The study was performed in five consecutive years from 2011 to 2016 at the Bulgarian Antarctic base camp at Livingston Island. The study protocol consisted of two parts: study A: duration of 15 days with measurement of skin physiology parameters on a daily basis, and study B: five measurements at baseline and at days 14, 30, 45 and 50 upon arrival in Antarctica. We measured three biophysical parameters related to skin physiology at cheek skin by an impedance measuring device. No statistically significant difference between parameters at the different measurement points. There is a variation in skin hydration reaching its lower point at day 11 and then returning to values similar to baseline. Initially, an increase in skin greasiness was witnessed with a sharp depression at day 11 and final values at day 15 resembling the ones at baseline. An increase, although not statistically significant, in skin roughness was observed in the first 15 days of the study. Study B showed no statistically significant variances between values of the three parameters. Our studies show the pioneer results of the effect of Antarctic climate on human skin physiology. © 2017 European Academy of Dermatology and Venereology.

  6. Safety of long-term subcutaneous free flap skin banking after skin-sparing mastectomy.

    PubMed

    Verstappen, Ralph; Djedovic, Gabriel; Morandi, Evi Maria; Heiser, Dietmar; Rieger, Ulrich Michael; Bauer, Thomas

    2018-03-01

    A persistent problem in autologous breast reconstruction in skin-sparing mastectomies is skin restoration after skin necrosis or secondary oncological resection. As a solution to facilitate reconstruction, skin banking of free-flap skin has been proposed in cases where the overlying skin envelope must be resected, as this technique spares the patient an additional donor site. Herein, we present the largest series to date in which this method was used. We investigated its safety and the possibility of skin banking for prolonged periods of time. All skin-sparing mastectomies and immediate autologous breast reconstructions from December 2009 until June 2013 at our institution were analysed. We identified 31 patients who underwent 33 free flap reconstructions in which skin banking was performed. Our median skin banking period was 7 days, with a maximum duration of 171 days. In 22.5% of cases, the banked skin was used to reconstruct overlying skin defects, and in 9.6% of cases to reconstruct the nipple-areolar complex. Microbiological and histological investigations of the banked skin revealed neither clinical infections nor malignancies. In situ skin banking, even for prolonged periods of time, is a safe and cost-effective method to ensure that skin defects due to necrosis or secondary oncological resection can be easily reconstructed.

  7. 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.

  8. HSP27 as a biomarker for predicting skin irritation in human skin and reconstructed organotypic skin model.

    PubMed

    Chen, Hongxia; Li, Shuhua; Meng, Tian; Zhang, Lei; Dai, Taoli; Xiang, Qi; Su, Zhijian; Zhang, Qihao; Huang, Yadong

    2014-04-21

    In vitro alternative tests aiming at replacing the traditional animal test for predicting the irritant potential of chemicals have been developed, but the assessing parameters or endpoints are still not sufficient. To discover novel endpoints for skin irritation responses, 2DE-based proteomics was used to analyze the protein expression in human skin exposed to sodium lauryl sulfate (SLS) following the test protocol of the European Centre for the Validation of Alternative Methods (ECVAM) in the present study. HSP27 was up-regulated most significantly among the eight identified proteins, consistent with our previous reports. Acid and basic chemicals were applied on human skin for further validation and results showed that the up-regulated expression of HSP27 was induced in 24h after the exposure. Skin-equivalent constructed with fibroblasts, basement membrane and keratinocytes was used to investigate the potential of HSP27 as a biomarker or additional endpoint for the hazard assessment of skin irritation. Our skin-equivalent (Reconstructed Organotypic Skin Model, ROSM) had excellent epidermal differentiation and was suitable for the skin irritation test. HSP27 also displayed an up-regulated expression in the ROSM in 24h after the irritants exposure for 15min. All these results suggest that HSP27 may represent a potential marker or additional endpoint for the hazard assessment of skin irritation caused by chemical products. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  9. Morphogenesis and Biomechanics of Engineered Skin Cultured Under Uniaxial Strain

    PubMed Central

    Blackstone, Britani N.; Powell, Heather M.

    2012-01-01

    Background Split-thickness autograft is the standard wound treatment for full-thickness burns. In large burns, sparse availability of uninjured skin prevents rapid closure of the wound, resulting in increased scar tissue formation or mortality. Tissue-engineered skin (ES) offers promise when autografts are not available. The Problem ES, constructed from a polymeric scaffold and skin cells, has been shown to reduce donor site area required to permanently close wounds, mortality, and morbidity from scarring but cannot restore all skin functions. Current generations of ES are orders of magnitude weaker than normal human skin, leading to difficulty in surgical application, greater susceptibility to mechanical damage during fabrication and application, and less elasticity and strength once engrafted. Basic/Clinical Science Advances Previous studies to improve ES biomechanics focus on altering the scaffolding material, which resulted in modest improvements but often inhibited proper skin development. As the skin is naturally under static strain, adding these mechanical cues to the culture environment is hypothesized to improve ES biomechanics. ES was cultured under applied static strains ranging from 0% to 40% strain for a total of 10 days. Strain magnitudes of 10% and 20% strain resulted in significantly stronger ES than unstrained controls, showed upregulation of many genes encoding structural extracellular matrix proteins, and exhibited increased epidermal cell proliferation and differentiation. Clinical Care Relevance Enhanced biomechanical properties of ES can allow for facile surgical application and less damage during dressing changes. Conclusion These findings suggest that mechanical cues play a significant role in skin development and should be further explored. PMID:24527283

  10. Tactile perception of skin and skin cream by friction induced vibrations.

    PubMed

    Ding, Shuyang; Bhushan, Bharat

    2016-11-01

    Skin cream smooths, softens, and moistens skin by altering surface roughness and tribological properties of skin. Sliding generates vibrations that activate mechanoreceptors located in skin. The brain interprets tactile information to identify skin feel. Understanding the tactile sensing mechanisms of skin with and without cream treatment is important to numerous applications including cosmetics, textiles, and robotics sensors. In this study, frequency spectra of friction force and friction induced vibration signals were carried out to investigate tactile perception by an artificial finger sliding on skin. The influence of normal load, velocity, and cream treatment time were studied. Coherence between friction force and vibration signals were found. The amplitude of vibration decreased after cream treatment, leading to smoother perception. Increasing normal load or velocity between contacting surfaces generated a smoother perception with cream treatment, but rougher perception without treatment. As cream treatment time increases, skin becomes smoother. The related mechanisms are discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. A review of patient and skin characteristics associated with skin tears.

    PubMed

    Rayner, R; Carville, K; Leslie, G; Roberts, P

    2015-09-01

    Skin tears are the most common wound among the elderly and have the potential to cause infection, form chronic wounds, reduce quality of life and increase health-care costs. Our aim was to identify studies that reviewed patient and skin characteristics associated with skin tears. A review of skin tear studies reported in the English literature between 1980 and 2013 was undertaken using the following electronic databases: PubMed, Medline, CINAHL, Embase, Scopus, Evidence Based and Medicine Reviews (EBM). Search terms included aged, skin, tears or lacerations, skin tearing, geri tear, epidermal tear and prevalence. There were 343 articles found with using the search terms. After abstract review nine were found to be relevant to the search. The principle findings from these eight published articles and one unpublished study revealed that the most common patient characteristics were a history of skin tears, impaired mobility and impaired cognition. Skin characteristics associated with skin tears included senile purpura, ecchymosis and oedema. This review provides an overview of identified patient and skin characteristics that predispose the elderly to skin tears and exposes the lack of research within this domain. R. Rayner is a recipient of a 2013 Australian Postgraduate Award, Curtin University Postgraduate Scholarship and a Wound Management Cooperative Research Centre (CRC) PhD stipend. The School of Nursing, Midwifery and Paramedicine, Curtin University and the Silver Chain Group, Western Australia are participants in the Wound Management Innovation CRC. No conflict of interest exists among the authors.

  12. 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

  13. Influence of staining solutions and whitening procedures on discoloration of hybrid composite resins.

    PubMed

    Garoushi, Sufyan; Lassila, Lippo; Hatem, Marwa; Shembesh, Muneim; Baady, Lugane; Salim, Ziad; Vallittu, Pekka

    2013-01-01

    The aim was to evaluate the color stability and water uptake of two hybrid composite resins polymerized in two different conditions after exposure to commonly consumed beverages. In addition, the effect of repolishing and bleaching on the stained composite was evaluated. Eighty specimens (12 mm × 12 mm × 3 mm) were made from two hybrid composite resins of shade A2. Forty specimens of each composite were divided into two groups (n = 20 per each) according to the curing method used (hand light cure HLC or oven light cure OLC). Then each group (HLC or OLC) was sub-divided randomly into four sub-groups (n = 5), which were immersed for 60 days in different beverages (distal water, coffee, tea and pepsi) and incubated at 37°C. Water uptake was measured during this time and followed by measurement of color difference (ΔE) by using a spectrophotometer. After complete staining, repolishing (grit 4000 FEPA at 300 rpm under water) and bleaching (40% hydrogen peroxide bleaching gel) were conducted. The repolished and bleached specimens were submitted to new color measurements. Color value of the specimens immersed in tea displayed the highest statistically significant (p < 0.05) mean color difference (ΔE) compared to other beverages, whereas the ΔE value of pepsi was significantly lower than the others. After staining of the composite resins, both the bleaching and repolishing were able to reduce the ΔE value. All beverages used affected the color stability of tested composite resins. The effect of beverages on color change of composites depends on type of beverage and water uptake value of resins used. A superior whitening effect was obtained with repolishing technique compared to bleaching.

  14. Safety of long-term subcutaneous free flap skin banking after skin-sparing mastectomy

    PubMed Central

    Verstappen, Ralph; Djedovic, Gabriel; Morandi, Evi Maria; Heiser, Dietmar; Rieger, Ulrich Michael; Bauer, Thomas

    2018-01-01

    Background A persistent problem in autologous breast reconstruction in skin-sparing mastectomies is skin restoration after skin necrosis or secondary oncological resection. As a solution to facilitate reconstruction, skin banking of free-flap skin has been proposed in cases where the overlying skin envelope must be resected, as this technique spares the patient an additional donor site. Herein, we present the largest series to date in which this method was used. We investigated its safety and the possibility of skin banking for prolonged periods of time. Methods All skin-sparing mastectomies and immediate autologous breast reconstructions from December 2009 until June 2013 at our institution were analysed. Results We identified 31 patients who underwent 33 free flap reconstructions in which skin banking was performed. Our median skin banking period was 7 days, with a maximum duration of 171 days. In 22.5% of cases, the banked skin was used to reconstruct overlying skin defects, and in 9.6% of cases to reconstruct the nipple-areolar complex. Microbiological and histological investigations of the banked skin revealed neither clinical infections nor malignancies. Conclusions In situ skin banking, even for prolonged periods of time, is a safe and cost-effective method to ensure that skin defects due to necrosis or secondary oncological resection can be easily reconstructed. PMID:29506331

  15. 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.

  16. ISOLATION OF RABBIT IGA ANTIHAPTEN ANTIBODY AND DEMONSTRATION OF SKIN-SENSITIZING ACTIVITY IN HOMOLOGOUS SKIN

    PubMed Central

    Onoue, Kaoru; Yagi, Yasuo; Pressman, David

    1966-01-01

    Multiple antibody components of rabbit antisera against p-azobenzenearsonate (Rp) were studied with respect to their globulin nature and skin-sensitizing activity. IgA antibody was characterized by isolating two IgA-rich fractions from a specifically purified antibody preparation. Examination of these fractions showed that IgA antibodies existed in two molecular forms, one with a sedimentation constant of 7S and the other 9S. Skin-sensitizing activity was examined by a P-K type test and a PCA test with Rp-rabbit serum albumin in homologous (rabbit) species. Only the 7S but not 9S IgA antibody sensitized rabbit skin. IgM antibody showed no activity and IgG antibody showed very low activity. In contrast, only IgG antibody was active in the P-K type test to sensitize a heterologous species (guinea pig). None of the antibodies of other classes showed sensitizing activity in heterologous skin. The 7S IgA antibody lost its sensitizing activity upon reduction and alkylation, although no change in its molecular size could be observed. The loss of sensitizing activity was not due to the destruction of antigen-binding activity since the treated 7S IgA antibody retained this activity as shown by radioimmunoelectrophoresis and by binding to the specific immunoadsorbent. The 9S IgA antibody was more resistant to these treatments than the IgM antibody and showed no indication of dissociation. The treated 9S IgA also retained antigen-binding activity. Both the P-K type and PCA reactions were considerably stronger when the interval between injections of antibody and antigen was 24 hr rather than 4 to 5 hr. PMID:4159250

  17. Appearance benefits of skin moisturization.

    PubMed

    Jiang, Z-X; DeLaCruz, J

    2011-02-01

    Skin hydration is essential for skin health. Moisturized skin is generally regarded as healthy and healthy looking. It is thus speculated that there may be appearance benefits of skin moisturization. This means that there are corresponding changes in the optical properties when skin is moisturized. The appearance of the skin is the result of light reflection, scattering and absorption at various skin layers of the stratum corneum, epidermis, dermis and beyond. The appearance benefits of skin moisturization are likely primarily due to the changes in the optical properties of the stratum corneum. We hypothesize that the major optical effect of skin moisturization is the decrease of light scattering at the skin surface, i.e., the stratum corneum. This decrease of surface scattering corresponds to an increase of light penetration into the deeper layers of the skin. An experiment was conducted to measure the corresponding change in skin spectral reflectance, the skin scattering coefficient and skin translucency with a change in skin hydration. In the experiment, skin hydration was decreased with the topical application of acetone and alcohol and increased with the topical application of known moisturizers and occlusives such as PJ. It was found that both the skin spectral reflectance and the skin scattering coefficient increased when the skin was dehydrated and decreased when the skin was hydrated. Skin translucency increased as the skin became moisturized. The results agree with the hypothesis that there is less light scattering at the skin surface and more light penetration into the deeper skin layers when the skin is moisturized. As a result, the skin appears darker, more pinkish and more translucent. © 2010 John Wiley & Sons A/S.

  18. Establishment of Demodex canis on canine skin engrafted onto scid-beige mice.

    PubMed

    Caswell, J L; Yager, J A; Barta, J R; Parker, W

    1996-12-01

    A small animal model of canine demodicosis is described. Normal canine skin was engrafted onto scid (severe combined immunodeficient)-beige mice, which lack functional B and T lymphocytes and have reduced natural killer cell activity. The xenografts were later infected with Demodex canis collected from a dog with demodicosis. At 30-112 days following infection, mites were seen histologically in the canine hair follicles of the engrafted skin. Demodex canis adults, nymphs, larvae, and eggs were present in samples macerated in sodium hydroxide. Mite infestations could not be demonstrated in the mouse skin, nor were mites passed from the infected graft to uninfected skin grafts on in-contact mice. This model may be utilized to assess the efficacy of miticidal treatments, to evaluate the importance of specific components of the immune response, and to study the biology of D. canis.

  19. Non-ablative skin tightening with radiofrequency in Asian skin.

    PubMed

    Kushikata, Nobuharu; Negishi, Kei; Tezuka, Yukiko; Takeuchi, Kaori; Wakamatsu, Shingo

    2005-02-01

    The recent successful application of radiofrequency (RF) in non-ablative skin tightening for skin laxity has attracted attention worldwide. The efficacy and clinical effect of RF were assessed in Asian skin, with additional study on the duration of the effect and any complications. Eighty-five Japanese females were enrolled in the study for treatment of nasolabial folds, marionette lines, and sagging jowls with 6-month follow-up. RF treatment was effective for nasolabial folds, marionette lines, and jowls. Objective physician evaluation found relatively good improvement at 3 months post-treatment, and even better improvement at the 6-month evaluation. RF treatment was very satisfactory for skin tightening in Asian facial skin. When compared with published literature from the United States, the results suggested that there might be race-related differences in the treatment parameters. (c) 2005 Wiley-Liss, Inc.

  20. 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 ...

  1. Skin and scales of teleost fish: Simple structure but high performance and multiple functions

    NASA Astrophysics Data System (ADS)

    Vernerey, Franck J.; Barthelat, Francois

    2014-08-01

    Natural and man-made structural materials perform similar functions such as structural support or protection. Therefore they rely on the same types of properties: strength, robustness, lightweight. Nature can therefore provide a significant source of inspiration for new and alternative engineering designs. We report here some results regarding a very common, yet largely unknown, type of biological material: fish skin. Within a thin, flexible and lightweight layer, fish skins display a variety of strain stiffening and stabilizing mechanisms which promote multiple functions such as protection, robustness and swimming efficiency. We particularly discuss four important features pertaining to scaled skins: (a) a strongly elastic tensile behavior that is independent from the presence of rigid scales, (b) a compressive response that prevents buckling and wrinkling instabilities, which are usually predominant for thin membranes, (c) a bending response that displays nonlinear stiffening mechanisms arising from geometric constraints between neighboring scales and (d) a robust structure that preserves the above characteristics upon the loss or damage of structural elements. These important properties make fish skin an attractive model for the development of very thin and flexible armors and protective layers, especially when combined with the high penetration resistance of individual scales. Scaled structures inspired by fish skin could find applications in ultra-light and flexible armor systems, flexible electronics or the design of smart and adaptive morphing structures for aerospace vehicles.

  2. Tensile Properties of Hydrogels and of Snake Skin

    NASA Technical Reports Server (NTRS)

    Hinkley, Jeffrey A.; Savitzky, Alan H.; Rivera, Gabriel; Gehrke, Stevin H.

    2002-01-01

    Stimulus-responsive or 'smart' gels are of potential interest as sensors and actuators, in industrial separations, and as permeable delivery systems. In most applications, a certain degree of mechanical strength and toughness will be required, yet the large-strain behavior of gels has not been widely reported. Some exceptions include work on gelatin and other food gels, some characterization of soft gels applicable for in-vitro cell growth studies, and toughness determinations on commercial contact lens materials. In general, it can be anticipated that the gel stiffness will increase with increasing degree of crosslinking, but the tensile strength may go through a maximum. Gel properties can be tailored by varying not only the degree of crosslinking, but also the polymer concentration and the nature of the polymer backbone (e.g. its stiffness or solubility). Polypeptides provide an especially interesting case, where secondary structure affects trends in moduli and conformational transitions may accompany phase changes. A few papers on the tensile properties of responsive gels have begun to appear. The responsive hydrogel chosen for the present study, crosslinked hydroxypropylcellulose, shrinks over a rather narrow temperature range near 44 C. Some vertebrate skin is also subject to substantial strain. Among reptiles, the morphologies of the skin and scales show wide variations. Bauer et al. described the mechanical properties and histology of gecko skin; longitudinal tensile properties of snake skin were examined by Jayne with reference to locomotion. The present measurements focus on adaptations related to feeding, including the response of the skin to circumferential tension. Tensile properties will be related to interspecific and regional variation in skin structure and folding.

  3. Skin Barrier Restoration and Moisturization Using Horse Oil-Loaded Dissolving Microneedle Patches.

    PubMed

    Lee, Chisong; Eom, Younghyon Andrew; Yang, Huisuk; Jang, Mingyu; Jung, Sang Uk; Park, Ye Oak; Lee, Si Eun; Jung, Hyungil

    2018-01-01

    Horse oil (HO) has skin barrier restoration and skin-moisturizing effects. Although cream formulations have been used widely and safely, their limited penetration through the stratum corneum is a major obstacle to maximizing the cosmetic efficacy of HO. Therefore, we aimed to encapsulate HO in a cosmetic dissolving microneedle (DMN) for efficient transdermal delivery. To overcome these limitations of skin permeation, HO-loaded DMN (HO-DMN) patches were developed and evaluated for their efficacy and safety using in vitro and clinical studies. Despite the lipophilic nature of HO, the HO-DMN patches had a sharp shape and uniform array, with an average length and tip diameter of 388.36 ± 16.73 and 38.54 ± 5.29 µm, respectively. The mechanical strength of the HO-DMN patches was sufficient (fracture force of 0.29 ± 0.01 N), and they could successfully penetrate pig skin. During the 4-week clinical evaluation, HO-DMN patches caused significant improvements in skin and dermal density, skin elasticity, and moisturization. Additionally, a brief safety assessment showed that the HO-DMN patches induced negligible adverse events. The HO-DMNs are efficient, safe, and convenient for wide use in cosmetic applications for skin barrier restoration and moisturization. © 2018 S. Karger AG, Basel.

  4. The whitening effect of bleaching agents on tetracycline-stained rat teeth.

    PubMed

    Shin, D H; Summitt, J B

    2002-01-01

    This study compared the whitening effect of three bleaching agents on the teeth of rats and demonstrated differences in bleaching where dentin was exposed or enamel was thin. Thirty Albino rats were peritoneally injected with tetracycline solution daily for two weeks. Thirty-two disc-shaped specimens were cut from the crowns of incisors removed from sacrificed rats and were irradiated with UV light for 16 hours. Sections were stored in saline. Eight sections served as controls and were not bleached. Three bleaching agents (Opalescence, Rembrandt and Nite White) were applied to eight specimens each, five times a day for two weeks, and images of the sections were recorded at the following times: before bleaching (baseline), day 1, day 3, day 5, day 7, day 9, day 11 and day 14. Mean colors to demonstrate any change (deltaE) from baseline for each time period were as follows: control-9.78 (baseline), 9.17, 9.36, 9.65, 9.40, 9.99, 10.57, 11.36; Opalescence-10.08, (baseline) 7.63, 6.72, 6.04, 5.10, 4.87, 4.89, 4.27; Rembrandt-9.83 (baseline), 11.27, 9.55, 8.36, 7.75, 6.94, 7.11, 7.04; Nite White-10.44 (baseline), 9.92, 7.58, 6.80, 5.45, 5.05, 4.73, 4.01. All bleached teeth were lightened (p<.01). Another 56 tetracycline-stained rat incisors were UV irradiated for three days. Three different penetration depths were tested: penetration through lingual dentin and labial enamel (DN group), penetration through labial enamel only (RE group) and penetration through labial enamel covered with 1.0 mm human enamel (HE group). Specimens were bleached with Opalescence for one hour five times a day for one week or four weeks. A control group of unbleached teeth was also examined. Results (deltaE) were as follows: control--11.67; 1-week DN--13.55; 1-week RE--12.80; 1-week HE--12.07; 4-week DN--7.48; 4-week RE--7.50; 4-week HE--11.69. The color change in the 4-week DN and the 4-week RE groups showed the greatest reduction (p<.01).

  5. 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. ...

  6. On the modeling and characterization of an interlocked flexible electronic skin

    NASA Astrophysics Data System (ADS)

    Khalili, Nazanin; Shen, Xuechen; Naguib, Hani E.

    2017-04-01

    Development of an electronic skin with ultra-high pressure sensitivity is now of critical importance due its broad range of applications including prosthetic skins and biomimetic robotics. Microstructured conductive composite elastomers can acquire mechanical and electrical properties analogous to those of natural skin. One of the most prominent features of human skin is its tactile sensing property which can be mimicked in an electronic skin. Herein, an electrically conductive composite comprising polydimethylsiloxane and conductive fillers is used as a flexible and stretchable piezoresistive sensor. The electrical conductivity is induced within the elastomer matrix via carbon nanotubes whereas the piezoresistivity is obtained by means of microstructuring the surface of the substrate. An interlocked array of pyramids in micro-scale allows the change in the contact resistance between two thin layers of the composite upon application of an external load. Deformation of the interlocked arrays endows the sensor with an ultra-high sensitivity to the external pressures within the range of human skin perception. Moreover, using finite element analysis, the change in the contact are between the two layers was captured for different geometries. The structure of the sensor can be optimized through an optimization model in order to acquire maximum sensitivity.

  7. Occupational Exposure to Ultraviolet Radiation and Risk of Non-Melanoma Skin Cancer in a Multinational European Study

    PubMed Central

    Surdu, Simona; Fitzgerald, Edward F.; Bloom, Michael S.; Boscoe, Francis P.; Carpenter, David O.; Haase, Richard F.; Gurzau, Eugen; Rudnai, Peter; Koppova, Kvetoslava; Févotte, Joëlle; Leonardi, Giovanni; Vahter, Marie; Goessler, Walter; Kumar, Rajiv; Fletcher, Tony

    2013-01-01

    Background Studies suggest that ambient sunlight plays an important role in the pathogenesis of non-melanoma skin cancers (NMSC). However, there is ongoing controversy regarding the relevance of occupational exposure to natural and artificial ultraviolet radiation (UV) radiation. Objectives We investigated potential associations between natural and artificial UV radiation exposure at work with NMSC in a case-control study conducted in Hungary, Romania, and Slovakia. Methods Occupational exposures were classified by expert assessment for 527 controls and 618 NMSC cases (515 basal cell carcinoma, BCC). Covariate information was collected via interview and multiple logistic regression models were used to assess associations between UV exposure and NMSC. Results Lifetime prevalence of occupational exposure in the participants was 13% for natural UV radiation and 7% for artificial UV radiation. Significant negative associations between occupational exposure to natural UV radiation and NMSC were detected for all who had ever been exposed (odds ratio (OR) 0.47, 95% confidence interval (CI) 0.27–0.80); similar results were detected using a semi-quantitative metric of cumulative exposure. The effects were modified by skin complexion, with significantly decreased risks of BCC among participants with light skin complexion. No associations were observed in relation to occupational artificial UV radiation exposure. Conclusions The protective effect of occupational exposure to natural UV radiation was unexpected, but limited to light-skinned people, suggesting adequate sun-protection behaviors. Further investigations focusing on variations in the individual genetic susceptibility and potential interactions with environmental and other relevant factors are planned. PMID:23638051

  8. 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 , ...

  9. 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 ...

  10. Experimental functional analysis of severe skin-picking behavior in Prader-Willi syndrome.

    PubMed

    Hall, Scott S; Hustyi, Kristin M; Chui, Clara; Hammond, Jennifer L

    2014-10-01

    Skin picking is an extremely distressing and treatment resistant behavior commonly shown by individuals with Prader-Willi syndrome (PWS). However, with the exception of a limited number of published single-case and survey studies, little is known about the environmental determinants of skin picking in this population. In this study, functional analyses were conducted with thirteen individuals with PWS, aged 6-23 years, who engaged in severe skin-picking behavior. In addition to the conditions typically employed in a functional analysis (i.e., alone, attention, play, demand), we included an ignore condition to examine potential effects of stimulus control by the presence of an adult. Twelve participants engaged in skin picking during the functional analysis, with the highest levels occurring in the alone and ignore conditions for eight participants, suggesting that skin picking in these participants was maintained by automatic reinforcement. For the remaining four participants, an undifferentiated pattern of low-rate skin picking was observed across conditions. These data confirm previous studies indicating that skin picking in PWS may be maintained most often by automatically produced sensory consequences. There were no associations between demographic characteristics of the participants (e.g., sex, age, IQ or BMI) and levels of skin picking observed in the functional analysis. Additional investigations are needed to identify the nature of the sensory consequences produced during episodes of skin picking in PWS. Behavioral interventions designed to extinguish or compete with the potential sensory consequences arising from skin picking in PWS are also warranted. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. The Skin Cancer and Sun Knowledge (SCSK) Scale: Validity, Reliability, and Relationship to Sun-Related Behaviors among Young Western Adults

    ERIC Educational Resources Information Center

    Day, Ashley K.; Wilson, Carlene; Roberts, Rachel M.; Hutchinson, Amanda D.

    2014-01-01

    Increasing public knowledge remains one of the key aims of skin cancer awareness campaigns, yet diagnosis rates continue to rise. It is essential we measure skin cancer knowledge adequately so as to determine the nature of its relationship to sun-related behaviors. This study investigated the psychometric properties of a new measure of skin cancer…

  12. Implantable biosensors: analysis of fluorescent light propagation through skin

    NASA Astrophysics Data System (ADS)

    O'Neal, D. P.; McShane, Michael J.; Pishko, Michael V.; Cote, Gerard L.

    2001-06-01

    Progress towards a painless and hygienic glucose monitoring procedure for diabetics continues as the growth of diabetes mellitus reaches epidemic proportions in the American population. Utilizing an implantable fluorescence based glucose assay, the minimally invasive approach presented here has previously shown promise towards this goal in terms of glucose specificity and quantification for in vitro environments. However, in realistic physiological circumstances the depth of the implant can vary and optical properties of skin can change due to normal physiological conditions. Additionally, naturally occurring auto-fluorescence can obscure the sensor signal. An important concern under these conditions is that variations of fluorescent intensity due to these or other causes might be mistaken for glucose concentration fluctuations. New data shows that fluorescence-based glucose assays can be probed and interpreted in terms of glucose concentrations through pig skin at depths of up to 700 mm when immobilized in a bio-compatible polymer. When a combination of two fluorophores are employed as demonstrated here, reasonable changes in skin thickness and the confounding effects of the variations inherent in skin can be overcome for this glucose sensing application.

  13. Biohydrogels for the In Vitro Re-construction and In Situ Regeneration of Human Skin

    NASA Astrophysics Data System (ADS)

    Korkina, Liudmila; Kostyuk, Vladimir; Guerra, Liliana

    Natural and synthetic biohydrogels are of great interest for the development of innovative medicinal and cosmetic products feasible for the treatment of numerous skin diseases and age-related changes in skin structure and function. Here, the characteristics of bio-resorbable hydrogels as scaffolds for the in vitro re-construction of temporary skin substitutes or full skin equivalents for further transplantation are reviewed. Another fast developing area of regenerative medicine is the in situ regeneration of human skin. The approach is mainly applicable to activate and facilitate the skin regeneration process and angiogenesis in chronic wounds with impaired healing. In this case, extracellular matrix resembling polymers are used to stimulate cell growth, adhesion, and movement. Better results could be achieved by activation of biocompatible hydrogels either with proteins (growth factors, adhesion molecules or/and cytokines) or with allogenic skin cells producing and releasing these molecules. Hydrogels are widely applied as carriers of low molecular weight substances with antioxidant, anti-inflammatory, anti-ageing, and wound healing action. Incorporation of these substances into hydrogels enhances their penetration through the skin barrier and prevents their destruction by oxidation. Potential roles of hydrogel-based products for modern dermatology and cosmetology are also discussed.

  14. Effects of Fermented Dairy Products on Skin: A Systematic Review.

    PubMed

    Vaughn, Alexandra R; Sivamani, Raja K

    2015-07-01

    Fermented dairy products, such as yogurt, have been proposed as a natural source of probiotics to promote intestinal health. Growing evidence shows that modulation of the gastrointestinal tract microbiota can modulate skin disease as well. This systematic review was conducted to examine the evidence for the use of ingested fermented dairy products to modulate skin health and function. We also sought to review the effects of the topical application of dairy products. The PubMed and Embase databases were systematically searched for clinical studies involving humans only that examined the relationship between fermented dairy products and skin health. A total of 312 articles were found and a total of 4 studies met inclusion criteria. Three studies evaluated the effects of ingestion, while one evaluated the effects of topical application. All studies noted improvement with the use of fermented dairy. Overall, there is early and limited evidence that fermented dairy products, used both topically and orally, may provide benefits for skin health. However, existing studies are limited and further studies will be important to better assess efficacy and the mechanisms involved.

  15. Skin disease prevalence study in schoolchildren in rural Côte d'Ivoire: Implications for integration of neglected skin diseases (skin NTDs).

    PubMed

    Yotsu, Rie Roselyne; Kouadio, Kouamé; Vagamon, Bamba; N'guessan, Konan; Akpa, Amari Jules; Yao, Aubin; Aké, Julien; Abbet Abbet, Rigobert; Tchamba Agbor Agbor, Barbine; Bedimo, Roger; Ishii, Norihisa; Fuller, L Claire; Hay, Roderick; Mitjà, Oriol; Drechsler, Henning; Asiedu, Kingsley

    2018-05-01

    Early detection of several skin-related neglected tropical diseases (skin NTDs)-including leprosy, Buruli ulcer, yaws, and scabies- may be achieved through school surveys, but such an approach has seldom been tested systematically on a large scale in endemic countries. Additionally, a better understanding of the spectrum of skin diseases and the at-risk populations to be encountered during such surveys is necessary to facilitate the process. We performed a school skin survey for selected NTDs and the spectrum of skin diseases, among primary schoolchildren aged 5 to 15 in Côte d'Ivoire, West Africa. This 2-phase survey took place in 49 schools from 16 villages in the Adzopé health district from November 2015 to January 2016. The first phase involved a rapid visual examination of the skin by local community healthcare workers (village nurses) to identify any skin abnormality. In a second phase, a specialized medical team including dermatologists performed a total skin examination of all screened students with any skin lesion and provided treatment where necessary. Of a total of 13,019 children, 3,504 screened positive for skin lesions and were listed for the next stage examination. The medical team examined 1,138 of these children. The overall prevalence of skin diseases was 25.6% (95% CI: 24.3-26.9%). The predominant diagnoses were fungal infections (n = 858, prevalence: 22.3%), followed by inflammatory skin diseases (n = 265, prevalence: 6.9%). Skin diseases were more common in boys and in children living along the main road with heavy traffic. One case of multi-bacillary type leprosy was detected early, along with 36 cases of scabies. Our survey was met with very good community acceptance. We carried out the first large-scale integrated, two-phase pediatric multi-skin NTD survey in rural Côte d'Ivoire, effectively reaching a large population. We found a high prevalence of skin diseases in children, but only limited number of skin NTDs. With the lessons learned

  16. Estrogens and aging skin.

    PubMed

    Thornton, M Julie

    2013-04-01

    Estrogen deficiency following menopause results in atrophic skin changes and acceleration of skin aging. Estrogens significantly modulate skin physiology, targeting keratinocytes, fibroblasts, melanocytes, hair follicles and sebaceous glands, and improve angiogenesis, wound healing and immune responses. Estrogen insufficiency decreases defense against oxidative stress; skin becomes thinner with less collagen, decreased elasticity, increased wrinkling, increased dryness and reduced vascularity. Its protective function becomes compromised and aging is associated with impaired wound healing, hair loss, pigmentary changes and skin cancer.   Skin aging can be significantly delayed by the administration of estrogen. This paper reviews estrogen effects on human skin and the mechanisms by which estrogens can alleviate the changes due to aging. The relevance of estrogen replacement, selective estrogen receptor modulators (SERMs) and phytoestrogens as therapies for diminishing skin aging is highlighted. Understanding estrogen signaling in skin will provide a basis for interventions in aging pathologies.

  17. Three-dimensional multispectral optoacoustic mesoscopy reveals melanin and blood oxygenation in human skin in vivo.

    PubMed

    Schwarz, Mathias; Buehler, Andreas; Aguirre, Juan; Ntziachristos, Vasilis

    2016-01-01

    Optical imaging plays a major role in disease detection in dermatology. However, current optical methods are limited by lack of three-dimensional detection of pathophysiological parameters within skin. It was recently shown that single-wavelength optoacoustic (photoacoustic) mesoscopy resolves skin morphology, i.e. melanin and blood vessels within epidermis and dermis. In this work we employed illumination at multiple wavelengths for enabling three-dimensional multispectral optoacoustic mesoscopy (MSOM) of natural chromophores in human skin in vivo operating at 15-125 MHz. We employ a per-pulse tunable laser to inherently co-register spectral datasets, and reveal previously undisclosed insights of melanin, and blood oxygenation in human skin. We further reveal broadband absorption spectra of specific skin compartments. We discuss the potential of MSOM for label-free visualization of physiological biomarkers in skin in vivo. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Xenobiotic metabolism in human skin and 3D human skin reconstructs: a review.

    PubMed

    Gibbs, Sue; van de Sandt, Johannes J M; Merk, Hans F; Lockley, David J; Pendlington, Ruth U; Pease, Camilla K

    2007-12-01

    In this review, we discuss and compare studies of xenobiotic metabolism in both human skin and 3D human skin reconstructs. In comparison to the liver, the skin is a less studied organ in terms of characterising metabolic capability. While the skin forms the major protective barrier to environmental chemical exposure, it is also a potential target organ for adverse health effects. Occupational, accidental or intended-use exposure to toxic chemicals could result in acute or delayed injury to the skin (e.g. inflammation, allergy, cancer). Skin metabolism may play a role in the manifestation or amelioration of adverse effects via the topical route. Today, we have robust testing strategies to assess the potential for local skin toxicity of chemical exposure. Such methods (e.g. the local lymph node assay for assessing skin sensitisation; skin painting carcinogenicity studies) incorporate skin metabolism implicitly in the in vivo model system used. In light of recent European legislation (i.e. 7(th) Amendment to the Cosmetics Directive and Registration Evaluation and Authorisation of existing Chemicals (REACH)), non-animal approaches will be required to reduce and replace animal experiments for chemical risk assessment. It is expected that new models and approaches will need to account for skin metabolism explicitly, as the mechanisms of adverse effects in the skin are deconvoluted. 3D skin models have been proposed as a tool to use in new in vitro alternative approaches. In order to be able to use 3D skin models in this context, we need to understand their metabolic competency in relation to xenobiotic biotransformation and whether functional activity is representative of that seen in human skin.

  19. 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

  20. Evaluation of a 6% hydrogen peroxide tooth-whitening gel on enamel microhardness after extended use.

    PubMed

    Toteda, Mariarosaria; Philpotts, Carole J; Cox, Trevor F; Joiner, Andrew

    2008-11-01

    To evaluate the effects of a 6% hydrogen peroxide tooth whitener, Xtra White, on sound human enamel microhardness in vitro after an extended and exaggerated simulated 8 weeks of product use. Polished human enamel specimens were prepared and baseline microhardness and color measurements determined. The enamel specimens were exposed to a fluoride-containing toothpaste for 30 seconds and then exposed to water, Xtra White, a control carbopol gel containing no hydrogen peroxide, or a carbonated beverage (each group, n = 8) for 20 minutes. Specimens were exposed to whole saliva at all other times. In order to simulate 8 weeks of extended product use, quadruple the length of the manufacturer's instructions, 112 treatments, were conducted. Microhardness measurements were taken after 2, 4, 6, and 8 weeks of simulated treatments, and color was measured after 2 and 8 weeks. The Xtra White-treated specimens showed a statistically significant (P < .0001) increase in L* and decrease in b* compared to the water-treated specimens after 2 weeks simulated use, indicating bleaching had occurred. The carbonated beverage-treated specimens were significantly softened (P = .0009) compared to baseline after only 1 treatment. The carbopol gel-treated specimens were significantly softened (P = .0028) after 2 weeks of simulated treatments compared to baseline. There were no statistically significant differences in enamel microhardness between baseline and all treatment times for XW and water groups. Xtra White does not have any deleterious effects on sound human enamel microhardness after an extended and exaggerated simulated 8 weeks of product use.