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The Hunt for Natural Skin Whitening Agents  [PDF]
Nico Smit,Jana Vicanova,Stan Pavel
International Journal of Molecular Sciences , 2009, DOI: 10.3390/ijms10125326
Abstract: 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.
Qualitative and Quantitative Estimation of Hydroquinone in Skin Whitening Cosmetics  [PDF]
Saima Siddique, Zahida Parveen, Zeeshan Ali, Muhammad Zaheer
Journal of Cosmetics, Dermatological Sciences and Applications (JCDSA) , 2012, DOI: 10.4236/jcdsa.2012.23042
Abstract: Hydroquinone has been used for decades as a skin lightening agent. Its use in cosmetics has been banned as a result of skin problems including contact dermatitis and ochronosis. A total of 22 samples of different skin whitening cosmetics were collected from local market. They were analyzed by using thin layer chromatography and HPLC for qualitative and quantitative determination of their hydroquinone contents. The hydroquinone was extracted from samples by using 96% ethanol and was subjected to TLC analysis. Eleven out of 22 samples were found to contain hydroquinone. The HPLC analysis showed the concentration of hydroquinone ranged from 0.002% to 0.092% in the cosmetic samples.
Mir-434-5p mediates skin whitening and lightening  [cached]
David TS Wu,Jack S Chen,Donald C Chang,Shi-Lung Lin
Clinical, Cosmetic and Investigational Dermatology , 2008,
Abstract: David TS Wu, Jack S Chen, Donald C Chang, Shi-Lung LinInstitute of Mello Biotechnology, Taipei, Taiwan, ROCAbstract: Utilization of gene silencing effectors, such as microRNA (miRNA) and small airpin RNA (shRNA), provides a powerful new strategy for human skin care in vivo, particularly for hyperpigmentation treatment and aging prevention. In this study, tyrosinase (Tyr), the rate-limiting enzyme of melanin (black pigment) biosynthesis, was served as a target for treatment of hyperpigmentation in mouse and human skins. There are over 54 native microRNA capable of silencing human tyrosinase for skin whitening and lightening. To this, we have designed a mir-434-5p homologue and used it to successfully demonstrate the feasibility of miRNA-mediated skin whitening and lightening in vitro and in vivo. Under the same experimental condition in the trials, Pol-II-directed intronic mir-434-5p expression did not cause any detectable sign of cytotoxicity, whereas siRNAs targeting the same sequence often induced certain nonspecific mRNA degradation as previously reported. Because the intronic miRNA-mediated gene silencing pathway is tightly regulated by multiple intracellular surveillance systems, including Pol-II transcription, RNA splicing, exosomal digestion and nonsense-mediated RNA decay (NMD), the current findings underscore the fact that intronic miRNA agents, such as manually re-designed mir-434-5p homologues, are effective, target-specific and safe to be used for skin whitening without any detectable cytotoxic effect. Given that the human skins also express a variety of other native miRNAs, we may re-design these miRNAs based on their individual functions for skin care, which may provide significant insights into areas of opportunity for new cosmetic and/or therapeutical applications.Keywords: microRNA, miRNA, mir-434, intron, gene silencing, RNAi, tyrosinase, melanin, cosmetics, pigmentation, skin whitening
Mir-434-5p mediates skin whitening and lightening
David TS Wu, Jack S Chen, Donald C Chang, Shi-Lung Lin
Clinical, Cosmetic and Investigational Dermatology , 2008, DOI: http://dx.doi.org/10.2147/CCID.S4181
Abstract: -434-5p mediates skin whitening and lightening Original Research (7664) Total Article Views Authors: David TS Wu, Jack S Chen, Donald C Chang, Shi-Lung Lin Published Date October 2008 Volume 2008:1 Pages 19 - 35 DOI: http://dx.doi.org/10.2147/CCID.S4181 David TS Wu, Jack S Chen, Donald C Chang, Shi-Lung Lin Institute of Mello Biotechnology, Taipei, Taiwan, ROC Abstract: Utilization of gene silencing effectors, such as microRNA (miRNA) and small airpin RNA (shRNA), provides a powerful new strategy for human skin care in vivo, particularly for hyperpigmentation treatment and aging prevention. In this study, tyrosinase (Tyr), the rate-limiting enzyme of melanin (black pigment) biosynthesis, was served as a target for treatment of hyperpigmentation in mouse and human skins. There are over 54 native microRNA capable of silencing human tyrosinase for skin whitening and lightening. To this, we have designed a mir-434-5p homologue and used it to successfully demonstrate the feasibility of miRNA-mediated skin whitening and lightening in vitro and in vivo. Under the same experimental condition in the trials, Pol-II-directed intronic mir-434-5p expression did not cause any detectable sign of cytotoxicity, whereas siRNAs targeting the same sequence often induced certain nonspecific mRNA degradation as previously reported. Because the intronic miRNA-mediated gene silencing pathway is tightly regulated by multiple intracellular surveillance systems, including Pol-II transcription, RNA splicing, exosomal digestion and nonsense-mediated RNA decay (NMD), the current findings underscore the fact that intronic miRNA agents, such as manually re-designed mir-434-5p homologues, are effective, target-specific and safe to be used for skin whitening without any detectable cytotoxic effect. Given that the human skins also express a variety of other native miRNAs, we may re-design these miRNAs based on their individual functions for skin care, which may provide significant insights into areas of opportunity for new cosmetic and/or therapeutical applications.
Knowledge, Attitude and Practice of Skin Whitening among Female University Students in Northeastern Nigeria
M. O. Amodu, M. T. Bolori, I. M. Ahmad, A. Kale, A. Kuchichi
Open Access Library Journal (OALib Journal) , 2018, DOI: 10.4236/oalib.1104501
Abstract:
Introduction: Skin whitening is the act of brightening the skin complexion by using substances that are applied on the skin or administered into the body by other means. The use of skin whitening agents has its drawback in terms of causing harmful effects such as skin disorders like depigmentation, rashes, pimples, discolorations, kidney damaged, cancers, neurological and psychiatric disorders depending on how the agents for skin whitening are used. Objective: The paper examines the knowledge, attitude and practice of skin whitening by university female students in north eastern Nigeria, where some dark skinned women in particular tend to bleach their skin. Method: A cross sectional descriptive study. Results: The awareness level of the students about skin whitening agents and their harmful effects was found to be high among the students and little below, half of them are already users of such agents mainly for beautification. Few of them think the use of skin whitening agents can be addictive and lead to social stigma but they don’t believe that the use of such agents should be restricted to medical only. Conclusion: Majority of the female students in the Universities in north-eastern Nigeria bleach their skin with dangerous chemical agents meant for other reasons mainly to attract the opposite sex despite having high knowledge of the harmful effects. Government is highly recommended to take the necessary steps to curtail such menace.
Mutagenic and Genotoxic Screening of Eight Commonly used Skin Whitening Creams in Nigeria
EE Akortha, MT Niemogha, O Edobor
Bayero Journal of Pure and Applied Sciences , 2012,
Abstract: Skin whitening (bleaching) creams are often used to deliberately lighten the skin in response to social pressures or for the treatment of skin pigmentation. Bleaching creams contain varied concentrations of hydroquinone, corticosteroids, ammoniated mercury and kojic acid. Prolonged use of these creams may have deleterious (mutagenic) effect on the genetic material (DNA) of body cells. The purpose of this study was to evaluate the mutagenicity potentials of eight commonly used bleaching creams (Body white, Tura, Maxitone, Movate, Amos white, Top gel, Ultra clair, Fair and white), using the modified Ames test (with and without metabolic activation) that uses the wild type Escherichia coli (0157:H7) as tester strain. The assay was examined for revertant strains of the organism with at least three alterations in the phenotypic characteristics of the wild type organism. Results obtained showed that the eight bleaching creams produced revertant strains of the organism with alteration in more than three of its phenotypic characteristics and compared favourably with the standard mutagen (ethidium bromide), which produced the same effect. Three mutation mechanisms (forward, backward and silent mutations) were identified. The introduction of liver enzymes (S9 mix) made no significant difference in the number of characteristics altered (p>0.05). The results of this study revealed that the eight bleaching creams were mutagenic in bacteria and could be said to possess carcinogenic potentials. Their mechanism of mutagenesis could also be by intercalation just as ethidium bromide.
Objective and Self-Perceived Facial Skin Status Using Whitening Efficacy of Cosmetic Products on Taiwanese Women  [PDF]
Hsin-Tung Lin, Gwo-Shing Chen, Feng-Lin Yen, Kuan-Nien Chen
Journal of Cosmetics, Dermatological Sciences and Applications (JCDSA) , 2016, DOI: 10.4236/jcdsa.2016.64015
Abstract: Background: Tranexamic acid and vitamin C derivatives are important reagent used in cosmetic skin-whitening products. Recently, self-perceptions regarding improvement in facial skin status have been increasingly recognized as an important outcome of whitening cosmetic products intervention. Aims: The purpose of the study was to determine the receptiveness of objective and self-perceived facial skin status using whitening cosmetic products. Methods: A total of 40 volunteers were photographed using the Visia? machine and completed questionnaires at pre- and post-operation (8 weeks after receiving whitening cosmetic products). Visia? digital image analysis and questionnaires were used for assessment of facial skin status. The receptiveness of objective and self-perceived measures was assessed by paired t test and Effect Size (ES). Results: There were progresses with regard to the surface spot (ES = 0.22), wrinkles (ES = 0.24), texture (ES = 0.31) and pores (ES = 0.21) after using cosmetic products with tranexamic acid. For self-perceived measures, there were significant progresses in pigmented spots (ES = 0.75), rough complexion (ES = 0.76), red complexion (ES = 0.41), wrinkle (ES = 0.58) and obvious pores (ES = 0.75). Conclusions: This study suggests that the whitening cosmetic products are associated with improvement of objective and self-perceived facial skin status. The results could be provided as available information for cosmetic investigation.
Application of Solid Phase Extraction on Multiwalled Carbon Nanotubes of Some Heavy Metal Ions to Analysis of Skin Whitening Cosmetics Using ICP-AES  [PDF]
Ayoub A. ALqadami,Mohammad Abulhassan Abdalla,Zeid A. ALOthman,Kamal Omer
International Journal of Environmental Research and Public Health , 2013, DOI: 10.3390/ijerph10010361
Abstract: 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%.
Berry skin development in Norton grape: Distinct patterns of transcriptional regulation and flavonoid biosynthesis
Mohammad B Ali, Susanne Howard, Shangwu Chen, Yechun Wang, Oliver Yu, Laszlo G Kovacs, Wenping Qiu
BMC Plant Biology , 2011, DOI: 10.1186/1471-2229-11-7
Abstract: A microarray study was conducted on transcriptome changes of Norton berry skin during the period of 37 to 127 days after bloom, which represents berry developmental phases from herbaceous growth to full ripeness. Samples of six berry developmental stages were collected. Analysis of the microarray data revealed that a total of 3,352 probe sets exhibited significant differences at transcript levels, with two-fold changes between at least two developmental stages. Expression profiles of defense-related genes showed a dynamic modulation of nucleotide-binding site-leucine-rich repeat (NBS-LRR) resistance genes and pathogenesis-related (PR) genes during berry development. Transcript levels of PR-1 in Norton berry skin clearly increased during the ripening phase. As in other grapevines, genes of the phenylpropanoid pathway were up-regulated in Norton as the berry developed. The most noticeable was the steady increase of transcript levels of stilbene synthase genes. Transcriptional patterns of six MYB transcription factors and eleven structural genes of the flavonoid pathway and profiles of anthocyanins and proanthocyanidins (PAs) during berry skin development were analyzed comparatively in Norton and Cabernet Sauvignon. Transcriptional patterns of MYB5A and MYB5B were similar during berry development between the two varieties, but those of MYBPA1 and MYBPA2 were strikingly different, demonstrating that the general flavonoid pathways are regulated under different MYB factors. The data showed that there were higher transcript levels of the genes encoding flavonoid-3'-O-hydroxylase (F3'H), flavonoid-3',5'-hydroxylase (F3'5'H), leucoanthocyanidin dioxygenase (LDOX), UDP-glucose:flavonoid 3'-O-glucosyltransferase (UFGT), anthocyanidin reductase (ANR), leucoanthocyanidin reductase (LAR) 1 and LAR2 in berry skin of Norton than in those of Cabernet Sauvignon. It was also found that the total amount of anthocyanins was markedly higher in Norton than in Cabernet Sauvignon berry skin
A Double-Blind, Placebo Controlled Clinical Trial Evaluating the Efficacy and Safety of a New Skin Whitening Combination in Patients with Chloasma  [PDF]
Xi Wang, Zhaoxia Li, Dan Zhang, Li Li, Seite Sophie
Journal of Cosmetics, Dermatological Sciences and Applications (JCDSA) , 2014, DOI: 10.4236/jcdsa.2014.42014
Abstract:

Melasma (or chloasma) is a hyperpigmentation disorder predominantly affecting sun-exposed skin in women, and is often refractory to treatment. The objective was to evaluate the efficacy and safety of a new whitening formula for the treatment of chloasma. This single centre, double-blind, placebo controlled, bilateral (split-face) comparison, was conducted on 44 Chinese subjects with chloasma during the winter season. The test formula was applied twice a day, for 12 weeks on left side of the face and a placebo formula on the right side of the face. Assessments included the use of the hemi-MASI (split-face Melasma Area Severity Index), both ultraviolet and standard photography, together with clinical evaluations of efficacy and safety at T0, T6 and T12 weeks. A significant difference between the 2-hemi-MASI was noticed after 6 and 12 weeks of treatment. This result was confirmed by the clinical evaluation of the dermatologists who recorded a significant improvement in the half-face treated with the new whitening formula compared with that treated with placebo (p = 0.003). The

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