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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Détoxification des composés dicarbonylés glyoxal et méthylglyoxal par le système glyoxalase et implications dans la protection des protéines au cours du vieillissement cutané / Detoxification of dicarbonyl compouds glyoxal and methylglyoxal by glyoxalase system and implications in protein protection during skin aging

Radjei, Sabrina 26 September 2014 (has links)
Le vieillissement de la peau est la résultante du chrono et du photo-vieillissement qui partagent des changements moléculaires incluant les modifications des protéines telles que la glycation. La glycation se produit lorsque le glucose ou ses dérivés dicarbonylés, le glyoxal et de méthylglyoxal, réagissent avec les protéines conduisant à la formation de produits de glycation avancée (AGE). Le but de ces travaux est de mieux comprendre le rôle des glyoxalases dans la détoxification des dicarbonyles et dans la protection des protéines au cours du vieillissement de la peau. Afin de comprendre la régulation du systeme dans la peau humaine pendant le chono et le photo-vieillissement, des coupes de peau de donneurs jeunes et âgées ont été analysées par immunohistochimie. Le système des glyoxalase, glyoxalase 1 (GLO1) et glyoxalase 2 (Glo2), et AGE ont été localisés et détectés dans les échantillons de peau. Pour comprendre le rôle des GLO en réponse au stress dicarbonyle, des kéartinocytes HaCaT ont été soumise à un stress dicarbonyle de 24h et l'expression et les activités des glyoxalases ont été déterminées. Enfin, des études protéomiques ont été réalisées sur des cellules HaCaT surexprimant Glo2 ou inhibant GLO1 et nous sommes en train d'identifier des protéines cibles des carboxymethyllysines. Nos résultats montrent que le système des glyoxalases est présent dans la peau en particulier dans les cellules basales et est capable de protéger les protéines cellulaires contre les dommages oxydatifs. Nous espérons que notre étude peut contribuer à comprendre le rôle des glyoxalases dans la maintenance protéique qui est un élément clé de l'homéostasie cellulaire au cours du vieillissement. / Skin aging is the result of intrinsic and photo-aging, due to UV exposure, that both share important molecular features including alterations of proteins such as glycation. Glycation occurs when glucose or its derivates the dicarbonyl compounds glyoxal and methylglyoxal react with proteins leading to the formation of advanced glycation endproducts (AGE). The aim of this work is to better understand the role of glyoxalases in the detoxification of dicarbonyls and in the protection of keratinocyte’s proteins during skin aging.In order to understand glyoxalases regulation in human skin during intrinsic and photo-aging, skin sections from young and old donors were analysed by immunohistochemistry. The glyoxalase system, glyoxalase 1 (Glo1) and glyoxalase 2 (Glo2), and AGE were localized and detected in the skin samples. To understand the role of glyoxalases in response to dicarbonyl stress, HaCaT keratinocytes were subjected to a 24h dicarbonyl stress and the expression and activities of glyoxalases were determined. HaCaT cells silenced for Glo1 or overexpressing Glo2 were developed and were used in proteomic studies to identify target proteins preferentially glycated by dicarbonyl compounds.Finally, proteomic studies were performed on cellular clones overexpressing Glo2 or inhibiting Glo1 and we are currently identifying proteins targets for carboxymethyllysine modifications.Our results show that glyoxalase system is present in skin especially in the basal cells and is able to protect cellular proteins against oxidative damages. We expect that our study may contribute to decipher the role of glyoxalases in protein maintenance, which is a key element of cellular homeostasis during aging.
22

The Role of the Stress Response Gene Gadd45b in Senescence

Magimaidas, Andrew January 2015 (has links)
The Gadd45 family of proteins (Gadd45a, Gadd45b, and Gadd45g) has been shown to act as stress sensors in response to various physiological and environmental stressors, including oncogenic stress. However, the role of Gadd45b in senescence remained unclear. Here, we show for the first time that primary mouse embryo fibroblasts (MEFs) from Gadd45b null mice proliferate slowly; accumulate increased levels of DNA damage, and senesce prematurely. Notably, this is in contrast with Gadd45a null MEFs that show enhanced growth rate and escape senescence. This difference in growth rate increases with increasing passage number, suggesting that senescence results from exposure to environmental stressors. The impaired proliferation and increased senescence in Gadd45b null MEFs can be partially reversed by culturing cells at physiological oxygen levels, indicating that in the absence of Gadd45b, primary MEFs are less able to cope with elevated levels of oxidative stress. Interestingly, in contrast to other senescent MEFs, which arrest at G1 phase of cell cycle, Gadd45b null MEFs arrest at the G2/M phase of cell cycle. Furthermore, FACS analysis of Gadd45b null MEFs showed less phospho-histone H3-positive cells compared to wild type MEFs indicating that Gadd45b null MEFs are arrested in G2 phase rather than M phase. Interestingly, other stressors such as sub-lethal H2O2 and UV irradiation, that are known to increase oxidative stress, triggered increased premature senescence in Gadd45b null MEFs compared to wild type MEFs. By staining embryos for SA-β-gal gal, we also show that embryos from Gadd45b null mice exhibit increased SA-β-gal gal staining compared to wild type embryos, thus providing in vivo evidence for increased senescence in Gadd45b null mice. Finally, investigating the effect of loss of Gadd45b on senescence related diseases, we show that loss of Gadd45b promotes senescence and aging phenotypes in the skin as well as increased senescence and attenuated fibrotic response to CCl4 induced liver fibrosis. Together, these results highlight a novel and significant role for Gadd45b in the senescence response of cells to stress. / Molecular Biology and Genetics
23

Estabilidade e eficácia clínica de formulações dermocosméticas contendo filtros solares, vitaminas lipossolúveis e extratos de Ginkgo biloba e algas marinhas vermelhas / Stability and clinical efficacy of dermocosmetic formulations containing UV filters, liposoluble vitamins and Ginkgo biloba and red alga extracts

Gianeti, Mirela Donato 28 March 2013 (has links)
A associação de substâncias ativas no desenvolvimento de produtos multifuncionais eficazes para a manutenção e restauração da integridade da pele têm sido imprescindível na área cosmética. Desta maneira, destaca-se a associação de filtros solares com substâncias antioxidantes, tais como as vitaminas lipossolúveis e os extratos vegetais, com propriedades de filtros solares biológicos, os quais podem fornecer benefícios únicos à pele, aumentando a proteção contra a radiação UV e melhorando suas condições e aspectos em geral. Ainda, no desenvolvimento de formulações cosméticas é fundamental a seleção rigorosa e o balanço adequado de matérias-primas para a obtenção de produtos seguros, eficazes e estáveis durante todo seu tempo de prateleira. Assim, o objetivo do presente projeto é a avaliação da estabilidade física e química e da eficácia clínica de formulações dermocosméticas contendo filtros solares, vitaminas lipossolúveis e extratos de Ginkgo biloba e de algas marinhas vermelhas. Para tal, foram desenvolvidas 11 formulações fotoprotetoras as quais foram acrescidas ou não dos extratos de Ginkgo biloba ou de algas marinhas vermelhas e/ou de uma associação de vitaminas lipossolúveis. Após a realização de testes preliminares de estabilidade, as formulações F11, F11X e F11N (á base de poliacrilamida, C13-14 isoparafina e lauret-7) não apresentaram sinais de instabilidade e, portanto, foram submetidas à avaliação da estabilidade física (reologia). As formulações F11X e F11N foram consideradas mais estáveis, uma vez que não apresentaram grandes variações nos parâmetros analisados durante o estudo reológico (viscosidade aparente mínima, índice de fluxo, índice de consistência e área de histerese) e foram então utilizadas nos estudos posteriores. No estudo de estabilidade química as formulações contendo as diferentes substâncias ativas apresentaram diferentes prazos de validades, sendo que para a formulação que continha a associação de extratos e vitaminas (F11XVGA), o prazo de validade foi considerado maior quando comparado com as formulações que continham estas substâncias isoladas. Na avaliação da compatibilidade cutânea nenhum sinal clínico ou sensação de desconforto foi observado. No estudo de quantificação do limiar de percepção a uma corrente elétrica a formulação contendo associação de vitaminas e extratos vegetais de Ginkgo biloba e algas marinhas vermelhas proporcionou um aumentou a sensibilidade das fibras Ab devido a um aumento da hidratação, o que é essencial para manter as condições de percepção da pele. Na avaliação do efeito protetor contra as variações do clima a formulação F1XVGA apresentou efeito significativo benéfico na sensação de hidratação da pele e uma tendência em melhorar a sensibilidade das fibras nervosas C e Ad. Após uma única aplicação formulação estudada aumentou o conteúdo aquoso do estrato córneo, mostrando, portanto, efeito hidratante na pele, e ainda protegeu a função barreira da pele. No estudo de eficácia clínica a a formulação multifuncional proposta proporcionou uma melhora na função barreira da pele e uma hidratação que atinge até as camadas mais profundas da epiderme, levando a uma melhora na aparência da pele pela diminuição de rugas e da aspereza cutânea, podendo ser proposta para prevenir e melhorar as condições da pele foto envelhecida. / The association of active substances in the development of multifunctional cosmetic products, to be effective for the maintenance and restoration of skin integrity, have been essential in cosmetic area. Thus, a combination of sunscreen with antioxidant substances, such as liposoluble vitamins derivatives and vegetable extracts may provide unique benefits to the skin, increasing their protection against UV radiation and improving their conditions and appearance. Further, in the development of cosmetic formulations it is essential to assure the selection and balance of raw materials desirable for obtaining safe, efface and stable cosmetic formulations. The objective of this study is to evaluate the physical and chemical stability and clinical efficacy of dermocosmetic formulations containing sunscreens, liposoluble vitamins and Ginkgo biloba and red sea algae extracts For this, formulations it were developed 11sunscrrens which were added or not with vegetables extracts of Ginkgo biloba or from red sea algae and / or a combination of liposoluble vitamins derivatives. After conducting preliminary stability tests, formulations F11, F11X and F11N (based on polyacrylamide, C13-14 isoparaffin and laureth-7) showed no signs of instability and therefore were evaluated for physical stability (rheology). The formulations F11X and F11N were considered more stable, since they do not show variations in the parameters examined during the rheology study (viscosity, flow index, and consistency index, and tixotrophy) and were then used in further studies. In the chemical stability study formulations containing different active substances showed different shelf lives, and the formulation containing the combination of active substances (F11XVGA), the shelf life was considered higher when compared with formulations containing these substances alone. In the assessment of skin compatibility no clinical signs or discomfort was observed. In the current perception threshold study the formulation containing the combination of vitamins and vegetable extracts increased sensitivity of the Ab fibers due to increased hydration, which is essential for maintaining conditions of skin perception. In the evaluations of the protective effect against the environments variations the formulation F1XVGA was effective on the beneficial feeling of hydration of the skin and a tendency to improve the sensitivity of nerve fibers C and Ad. After a single application, the studied formulation increased the water content of the stratum corneum, showing therefore moisturizing effect on the skin, and also protected the skin barrier function. In clinical efficacy study the multifunctional proposed formulation provided an improvement in skin barrier function and hydrations until the deeper layers of the epidermis, leading to an improvement in skin appearance by reducing wrinkles and skin roughness, which can be suggest preventing and improving skin conditions mainly related with photo aging.
24

Luz intensa pulsada e ácido 5 aminolevulínico no tratamento de queratoses actínicas e fotoenvelhecimento facial / Intense pulsed light and aminolevulinic acid in the treatment of photodamage and actinic kearatosis

Haddad, Alessandra [UNIFESP] 28 April 2010 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:50:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-04-28 / INTRODUÇÃO: Rejuvenescimento fotodinâmico refere-se ao tratamento do fotoenvelhecimento e das queratoses actínicas. OBJETIVO: Avaliar a eficácia da terapia fotodinâmica com ácido aminolevulínico a 20% (ALA) ¾ tópico e luz intensa pulsada no tratamento das queratoses actínicas e do fotoenvelhecimento facial. MÉTODOS: Quarenta e três pacientes com idade média 71,3 anos, fototipos de pele I e IV divididos em: Controle (aplicação LIP/18J); Tratamento-I (ALA incubado por duas horas; ativado por duas passagens de LIP/16J); Tratamento-II (ALA; duas passagens de LIP/18J), foram avaliados por dois observadores, clínica e fotograficamente, no Pré, 48 horas, 8 e 12 semanas após, pela escala de Griffiths. Cinco queratoses actínicas foram marcadas como alvo para contagem no Pós- Tratamento, sendo uma submetida à biopsia antes e depois do tratamento, para avaliação anatomopatológica de atipias e perda de polaridade. RESULTADOS: Testes não-paramétricos mostraram melhora significativa (rugas finas, alterações texturais, pigmentação irregular) nos Grupos-Tratamento-I/II. No Grupo Controle, significância apenas para alterações pigmentares. Queratoses actínicas tiveram redução maior nos Grupos II (68, 4%) e I (51,2%) em relação ao Controle (5%). Houve redução significativa da gravidade das atipias e perda de polaridade nos Grupos-TratamentoI/II em relação ao controle. CONCLUSÃO: A terapia fotodinâmica, com ácido 5aminolevulínico e luz intensa pulsada, mostrou-se efetiva no tratamento do fotoenvelhecimento e das queratoses actínicas faciais. O tratamento das queratoses actínicas foi mais efetivo com uso de maior energia. / BACKGROUND: Photodynamic rejuvenation is the term used to the treatment of actinic keratosis and photodamage with photodynamic therapy. OBJECTIVE: Evaluate the efficacy of photodynamic therapy with aminolevulinic acid and intense pulsed light in the treatment of actinic keratosis and photodamage. METHODS: Fourty three patients mean age 71,3 years, were randomized in three groups: Control (IPL 18J); Treatment I (ALA+ IPL 16J); and Treatment II ( ALA+ IPL 18J) and evaluated clinically an photographically by two observers in Pre, 48hs, 8 weeks and 12 weeks Post-Treatment using Griffth’s Photonumeric Scale. Five actinic keratosis were marked as target in Pre-Treatment and biopsies Pre and Post-Treatment were done in one lesion to evaluate atypias and loss of cellular polarity. RESULTS: Non parametric tests showed marked improvement in mottled pigmentation, texture fine wrinkles in Groups Treatment I and II. In Control Group improvement only in mottled pigmentation. Actinic Keratosis clearance in Groups Treatment I and II were 51,2% and 68,4% respectively, whereas in Group Control it was 5%. In relation to Control Group, Groups Treatment I and II showed significant reduction of atypias and improvement in loss of cellular polarity. CONCLUSIONS: Photodynamic therapy with aminolevulinic acid and intense pulsed light is effective in the treatment of photodamage and actinic keratosis. The resolution of actinic keratosis was better with higher levels of energy. / TEDE / BV UNIFESP: Teses e dissertações
25

Estabilidade e eficácia clínica de formulações dermocosméticas contendo filtros solares, vitaminas lipossolúveis e extratos de Ginkgo biloba e algas marinhas vermelhas / Stability and clinical efficacy of dermocosmetic formulations containing UV filters, liposoluble vitamins and Ginkgo biloba and red alga extracts

Mirela Donato Gianeti 28 March 2013 (has links)
A associação de substâncias ativas no desenvolvimento de produtos multifuncionais eficazes para a manutenção e restauração da integridade da pele têm sido imprescindível na área cosmética. Desta maneira, destaca-se a associação de filtros solares com substâncias antioxidantes, tais como as vitaminas lipossolúveis e os extratos vegetais, com propriedades de filtros solares biológicos, os quais podem fornecer benefícios únicos à pele, aumentando a proteção contra a radiação UV e melhorando suas condições e aspectos em geral. Ainda, no desenvolvimento de formulações cosméticas é fundamental a seleção rigorosa e o balanço adequado de matérias-primas para a obtenção de produtos seguros, eficazes e estáveis durante todo seu tempo de prateleira. Assim, o objetivo do presente projeto é a avaliação da estabilidade física e química e da eficácia clínica de formulações dermocosméticas contendo filtros solares, vitaminas lipossolúveis e extratos de Ginkgo biloba e de algas marinhas vermelhas. Para tal, foram desenvolvidas 11 formulações fotoprotetoras as quais foram acrescidas ou não dos extratos de Ginkgo biloba ou de algas marinhas vermelhas e/ou de uma associação de vitaminas lipossolúveis. Após a realização de testes preliminares de estabilidade, as formulações F11, F11X e F11N (á base de poliacrilamida, C13-14 isoparafina e lauret-7) não apresentaram sinais de instabilidade e, portanto, foram submetidas à avaliação da estabilidade física (reologia). As formulações F11X e F11N foram consideradas mais estáveis, uma vez que não apresentaram grandes variações nos parâmetros analisados durante o estudo reológico (viscosidade aparente mínima, índice de fluxo, índice de consistência e área de histerese) e foram então utilizadas nos estudos posteriores. No estudo de estabilidade química as formulações contendo as diferentes substâncias ativas apresentaram diferentes prazos de validades, sendo que para a formulação que continha a associação de extratos e vitaminas (F11XVGA), o prazo de validade foi considerado maior quando comparado com as formulações que continham estas substâncias isoladas. Na avaliação da compatibilidade cutânea nenhum sinal clínico ou sensação de desconforto foi observado. No estudo de quantificação do limiar de percepção a uma corrente elétrica a formulação contendo associação de vitaminas e extratos vegetais de Ginkgo biloba e algas marinhas vermelhas proporcionou um aumentou a sensibilidade das fibras Ab devido a um aumento da hidratação, o que é essencial para manter as condições de percepção da pele. Na avaliação do efeito protetor contra as variações do clima a formulação F1XVGA apresentou efeito significativo benéfico na sensação de hidratação da pele e uma tendência em melhorar a sensibilidade das fibras nervosas C e Ad. Após uma única aplicação formulação estudada aumentou o conteúdo aquoso do estrato córneo, mostrando, portanto, efeito hidratante na pele, e ainda protegeu a função barreira da pele. No estudo de eficácia clínica a a formulação multifuncional proposta proporcionou uma melhora na função barreira da pele e uma hidratação que atinge até as camadas mais profundas da epiderme, levando a uma melhora na aparência da pele pela diminuição de rugas e da aspereza cutânea, podendo ser proposta para prevenir e melhorar as condições da pele foto envelhecida. / The association of active substances in the development of multifunctional cosmetic products, to be effective for the maintenance and restoration of skin integrity, have been essential in cosmetic area. Thus, a combination of sunscreen with antioxidant substances, such as liposoluble vitamins derivatives and vegetable extracts may provide unique benefits to the skin, increasing their protection against UV radiation and improving their conditions and appearance. Further, in the development of cosmetic formulations it is essential to assure the selection and balance of raw materials desirable for obtaining safe, efface and stable cosmetic formulations. The objective of this study is to evaluate the physical and chemical stability and clinical efficacy of dermocosmetic formulations containing sunscreens, liposoluble vitamins and Ginkgo biloba and red sea algae extracts For this, formulations it were developed 11sunscrrens which were added or not with vegetables extracts of Ginkgo biloba or from red sea algae and / or a combination of liposoluble vitamins derivatives. After conducting preliminary stability tests, formulations F11, F11X and F11N (based on polyacrylamide, C13-14 isoparaffin and laureth-7) showed no signs of instability and therefore were evaluated for physical stability (rheology). The formulations F11X and F11N were considered more stable, since they do not show variations in the parameters examined during the rheology study (viscosity, flow index, and consistency index, and tixotrophy) and were then used in further studies. In the chemical stability study formulations containing different active substances showed different shelf lives, and the formulation containing the combination of active substances (F11XVGA), the shelf life was considered higher when compared with formulations containing these substances alone. In the assessment of skin compatibility no clinical signs or discomfort was observed. In the current perception threshold study the formulation containing the combination of vitamins and vegetable extracts increased sensitivity of the Ab fibers due to increased hydration, which is essential for maintaining conditions of skin perception. In the evaluations of the protective effect against the environments variations the formulation F1XVGA was effective on the beneficial feeling of hydration of the skin and a tendency to improve the sensitivity of nerve fibers C and Ad. After a single application, the studied formulation increased the water content of the stratum corneum, showing therefore moisturizing effect on the skin, and also protected the skin barrier function. In clinical efficacy study the multifunctional proposed formulation provided an improvement in skin barrier function and hydrations until the deeper layers of the epidermis, leading to an improvement in skin appearance by reducing wrinkles and skin roughness, which can be suggest preventing and improving skin conditions mainly related with photo aging.
26

Učestalost, vrsta i lokalizacija premalignih i malignih lezija kože kod bolesnika nakon transplantacije bubrega / Frequency, type and localization of premalignant and malignant skin lesions in renal transplant recipients

Roš Tatjana 27 September 2016 (has links)
<p>Osobe kojima su transplantirani organi imaju povećan rizik pojave malignih oboljenja, među kojima dominiraju maligni tumori kože. Smatra se da je osnovni razlog primena imunosupresivne terapije, ali jo&scaron; nije sasvim jasan mehanizam i nivo dejstva različitih imunosupresiva. Važan uticaj na nastanak većine malignih tumora kože ima ultraljubičasto (UV) zračenje koje izaziva pojačano starenje kože u vidu histolo&scaron;ki prepoznatljivog fotoo&scaron;tećenja, sa odlikama razvoja elastoze i limfocitne infiltracije. U na&scaron;oj zemlji do sada nisu sprovođena istraživanja rizika pojave maligniteta kože kod transplantiranih pacijenata, ne postoje podaci o njihovoj incidenci, uticaju imunosupresivne terapije i drugim potencijalnim faktorima rizika. U dostupnoj literaturi nema objavljenih radova iz oblasti analize histolo&scaron;kog fotoo&scaron;tećenja kože kod osoba na imunosupresivnoj terapiji. Ciljevi ove studije preseka bili su utvrđivanje učestalosti, vrste i lokalizacije premalignih i malignih lezija kože kod pacijenata nakon transplantacije bubrega, povezanosti njihove pojave sa dužinom, vrstom i režimom primene imunosupresivne terapije i sa histolo&scaron;ki verifikovanim fotoo&scaron;tećenjem perilezionalne kože. U studiju je uključeno 66 pacijenata kojima je transplantiran bubreg (primaoci organskog transplantata &ndash; POT). Relevantni podaci su prikupljeni putem upitnika i iz medicinske dokumentacije, kliničko-dermoskopskim pregledom kože uočene suspektne lezije su bioptirane u cilju postavljanja dijagnoze i utvrđivanja histolo&scaron;kih parametara fotoo&scaron;tećenja, a u studiju su uključeni i maligni tumori kože POT ispitanika uklonjeni u periodu od prethodnih 5 godina ali nakon transplantacije. Radi komparacije prisutnih faktora rizika i stepena fotoo&scaron;tećenja kože sa op&scaron;tom populacijom formirana je kontrolna grupa (KG) ispitanika kojima je prethodno bioptirana koža, bez oboljenja bubrega i bez imunosupresije, slična po polu i životnoj dobi sa onim POT ispitanicima kojima je urađena biopsija. Za svaku leziju iz POT grupe obezbeđene su po 2 lezije iz KG, tako da je pojedinim ispitanicima POT grupe analizirano vi&scaron;e lezija, dok je u KG 1 ispitanik &ndash; 1 lezija. Osnovno oboljenje bubrega do započinjanja dijalize kod ispitanika POT grupe prosečno je trajalo 7,67 godina, u strukturi oboljenja bubrega dominirao je hronični glomerulonefritis sa 31,8%, a ispitanici su na dijalizi bili prosečno 4,54 godine. Prosečna životna dob ispitanika u momentu transplantacije iznosila je 42,5 godina, 60,6% imalo je isključivo kadaveričnu transplantaciju, a prosečno trajanje jatrogene imunosupresije iznosilo je 4,89 god. U POT grupi bioptirane su 33 lezije, među kojima su od značaja za studiju bile 2 (6,1%) aktinične keratoze (AK), 3 (9,1%) displastična nevusa (DN), 1 (3,0%) melanom (MM), 3 (9,1%) skvamocelularna karcinoma (SCK) i 6 (18,2%) bazocelularnih karcinoma (BCK). U POT grupi učestalost MM bila je 1,5%, učestalost SCK 4,5%, učestalost BCK 9,1%, dok je utvrđeni relativan rizik pojave MM u POT populaciji 227 puta veći, BCK 316 puta veći, a SCK 805 puta veći nego u op&scaron;toj populaciji. Relativan rizik nastanka AK i DN nije određen zbog izostanka zvanične registracije u op&scaron;toj populaciji. POT grupa i KG nisu se statistički značajno razlikovale po Ficpatrikovom fototipu kože, profesionalnoj izloženosti UV zračenju, upotrebi solarijuma, broju solarnih opekotina, ličnoj anamnezi malignih tumora kože i konzumiranju cigareta. Pripadnici KG su se značajno vi&scaron;e rekreativno izlagali UV zračenju, če&scaron;će koristili sredstva za za&scaron;titu od sunčevog zračenja, če&scaron;će imali bliske srodnike sa malignim tumorima kože, če&scaron;će konzumirali alkohol, značajno veći broj ispitanika KG imao je pregled kompletne kože i informaciju o merama prevencije od strane lekara, dok 50% ispitanika POT grupe nije znalo da su pod povećanim rizikom pojave maligniteta kože. U stepenu elastoze među grupama nije postojala statistički značajna razlika, dok je limfocitna infiltracija bila marginalno izrazitija u POT grupi bez obzira na vrstu lezije. U POT grupi utvrđena je statistički značajna povezanost prisustva malignog tumora sa većim stepenom perilezionalne limfocitne infiltracije i elastoze. U KG utvrđena je statistički značajna povezanost prisustva malignog tumora sa većim stepenom limfocitne infiltracije, dok nije bilo statistički značajne razlike u stepenu perilezionalne elastoze. U studiji je utvrđeno da osobe nakon transplantacije bubrega imaju statistički značajno veći rizik nastanka BCK, SCK i MM kože u odnosu na op&scaron;tu populaciju, sa najče&scaron;ćom lokalizacijom ovih tumora u predelu glave. Dužina primene imunosupresivne terapije uop&scaron;teno nije statistički značajno uticala na pojavu premalignih i malignih tumora kože, ali je kumulativna doza pojedinih imunosupresiva poput ciklosporina i azatioprina imala statistički značajan uticaj na pojavu premalignih i malignih lezija kože. Dužina imunosupresije je statistički značajno uticala na stepen elastoze, ali je imala marginalan uticaj na stepen perilezionalne limfocitne infiltracije.</p> / <p>Organ transplant recipients are at an increased risk of developing malignancies, with the predominance of malignant skin tumors. The main cause is considered to be the administration of immunosuppressive therapy, but the mechanism and effect levels of different immunosuppressive agents are still not completely clear. Ultraviolet (UV) rays also influence the development of malignant skin tumors, causing increased skin aging with histologically recognisable photo damage, with its hallmark being development of elastosis and lymphocytic infiltration. No research on the topic of risks of malignant skin tumors in transplant patients has been done in our country, there is no data on their incidence, or on the effects of immunosuppressive agents and other potential risk factors. There are also no published studies in the field of hystological photo damage analysis in patients on immunosuppressive therapy. The aims of this study were to establish the rates of occurance, types and localisation of premalignant and malignant skin lesions in kidney transplant recipients (KTR) and to associate their advent with the length, type and regimen of immunosuppressive therapy. A total of 66 KTR patients were enrolled in the study. Relevant information was gathered through a specially constructed questionnaire and from the medical records, followed by combined clinical and dermoscopic skin examination to detect suspicious lesions which were biopsied in order to determine the histopathologic diagnosis of the lesion and perilesional degree of photo damage. The study also encompassed malignant skin tumors of KTR patients that have been removed in the last 5 years, but after the transplantation. For the sake of comparison of the risk factors and the levels of photo damage with the general population, an age and sex - matched control group (CG) of patients with previous skin biopsy but without kidney disease and immunosuppression was formed. For each lesion from KTR group, 2 lesions from CG were provided, meaning that some KTR patients had several lesions analysed, whereas in the CG only 1 lesion per patient was analyzed. The average duration of underlying kidney diseases in KTR was 7,67 years, the most frequent being chronic glomerulonephritis (31,8%), and an average duration of dialysis was 4,54 years. The mean age at transplantation was 42,5 years, with 60,6% of the KTR having exclusively cadaveric graft. The mean duration of the iatrogenic immunosuppression was 4,89 years. In the KTR group a total of 33 lesions were biopsied, 2 of which were actinic keratoses (AK) (6,1%), 3 were dysplastic nevi (DN) (9,1%), 1 melanoma (MM) (3,0%), 3 squamous cell carcinomas (SCC) (9,1%) and 6 basal cell carcinomas (BCC) (18,2%). The estimated frequency of MM was 1,5%, SCC 4,5%, BCC 9,1%, and the estimated relative risk of MM in KTR being 227, BCC 316, and SCC 805 times higher compared to the general population. The relative risk of AK and DN development could not have been estimated as there are no official records in the general population. The KTR and CG were not significantly different judging by the Fitzpatrick skin phototype, occupational UV exposure, sunbed usage, personal history of skin cancers, or smoking. The controls were recreationally more exposed to UV rays, used sun protective measures more frequently, had more relatives with skin cancers and consumed alcohol more frequently. A significantly greater number of controls had had complete skin examination and protective measures counceling by the doctor, while 50% of KTR patients did not even know that they were at an increased risk of malignant skin tumor development. There was no significant difference in elastosis levels among the groups, whereas the lymphocitic infiltration was only marginally greater in the KTR group. A significant association between the level of perilesional photodamage and developement of malignant tumors was estimated for the KTR group, whereas in the CG only the perilesional lymphocitic infiltration was strongly associated to malignant lesions. The study results suggest that KTR patients have a significantly higher risk of BCC, SCC and MM development in comparison with the general population, the most common localisation being in the head region. The duration of the immunosuppressive therapy had no significant effect on the premalignant and malignant tumors development, whereas the cummulative dose of certain immunosuppressives (such as cyclosporine and azathioprine) affected the development notably. The duration of immunosuppression statistically influenced the elastosis levels, but had only a marginal influence on the perilesional lymphocitic infiltration levels.</p>
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Estudo comparativo da pele pré e pós-laser fracionado minimamente ablativo com Erbium-YAG de 2940nm para tratamento de rítides da região perioral: avaliação clínica, anátomo-patológica e imuno-histoquímica / Comparative study of skin pre and post fractional photothermolysis with Erbium-YAG 2940nm for the treatment of perioral wrinkles: a clinical, histological and immunohistochemical analysis

Odo, Lilian Mayumi 24 March 2010 (has links)
Atualmente existem diversas opções terapêuticas para o tratamento do fotoenvelhecimento cutâneo.Uma das formas de tratamento muito utilizada é a fototerapia com laser. Com o desenvolvimento da tecnologia em lasers surgiu um novo conceito de tratamento da pele envelhecida, a fototermólise fracionada microablativa. Essa tecnologia fracionada visa combinar os efeitos visíveis de uma terapia ablativa com o conforto e segurança dos métodos não ablativos. Antes de atingir a pele o laser passa por uma lente óptica especial que o divide em microrraios. Tal procedimento produz colunas de lesões térmicas microscópicas que penetram na epiderme e derme, sem danificar o tecido circunvizinho. A grande vantagem de ser fracionado é que a pele íntegra ao redor de cada coluna funciona como um reservatório de células potentes para a rápida cicatrização e regeneração da pele, culminando com a produção de colágeno e resultando em uma pele mais jovial, sem o inconveniente de um longo período de recuperação pós-tratamento. 20 pacientes foram selecionadas para o tratamento das rítides periorais com uma sessão de laser Erbium-YAG de 2940nm, fracionado. Após 28 dias do procedimento observou-se melhora na textura da pele, clareamento de manchas e atenuação de rugas finas periorais. Foi realizado um estudo comparativo da quantificação das células de Langerhans e receptores toll-like ( TLRs ) 2, 3 e 9 na epiderme, antes e após 3, 7, 14 e 28 dias do tratamento e da quantificação das fibras de colágeno na derme superior, antes e após 28 dias do laser. Houve diferenças estatisticamente significativas entre as medianas dos valores de CD1a (p = 0,0085), TLR 2 (p = 0,0108), TLR 3 (p = 0,0011) e TLR 9 (p = 0,0012) na epiderme pré e pós-tratamento. Foi constatado que a significância se deu entre os valores: antes e após 14 dias para CD1a (diminuição), antes e após 7 dias para TLR 2 (diminuição), antes e após 14 dias para TLR 3 (aumento), antes e após 7 dias para TLR 9 (diminuição). Não se encontraram diferenças estatisticamente significativas entre os valores medianos das fibras colágenas do tipo I (p = 1,0000) e III (p = 0,3125) antes e após 28 dias do tratamento. O protocolo desse estudo mostrou-se bastante seguro, pois apresentou efeitos colaterais transitórios e nenhuma complicação permanente. / There are several treatment options for skin photoaging. One of them widely used nowadays is lasertherapy. The development of lasers technology introduced a new therapeutic concept for aging skin: ablative fractional photothermolysis. This technology combines the visible effects of an ablative therapy with the comfort and safety of nonablative methods. Before reaching the skin the laser passes through a special optical lens that splits it into tiny rays. This procedure produces columns of microscopic thermal injuries that penetrate the epidermis and dermis, without damaging the surrounding tissue. The great advantage of the fractional photothermolysis is that the intact skin around each column acts as a potent reservoir of cells for fast healing and skin regeneration, resulting in collagen production and a youthful skin without the inconvenience of a long period of recovery after treatment. 20 patients were selected for perioral wrinkles treatment with a session of fractional Erbium-YAG 2940nm. After 28 days of the procedure the perioral skin showed improvement in texture, bleaching of sunspots and attenuation of superficial wrinkles. A comparative study was conducted between the expression of Langerhans cells and toll-like receptors 2, 3 and 9 in the epidermis, before and after 3,7,14 and 28 days of treatment and among collagen fibers in the dermis, before and after 28 days of the laser. There were statistically significant differences between the median values of CD1a (p = 0.0085), TLR 2 (p = 0.0108), TLR 3 (p = 0.0011) and TLR 9 (p = 0.0012) in the epidermis pre and post-treatment. The significance occurred between the values: before and after 14 days for CD1a (decrease) before and after 7 days to TLR 2 (decrease) before and after 14 days for TLR 3 (increase) before and after 7 days for TLR 9 (decrease). There were not statistically significant differences between the median values of collagen type I (p = 1.0000) and III (p = 0.3125) before and after 28 days of treatment. The irradiation of skin with fractional Erbium-YAG was safe, as it showed transitory side effects and no permanent complication.
28

Évolution de modèles tridimensionnels de peau reconstruite pour approfondir la connaissance des mécanismes du vieillissement cutané et validation de l’efficacité « anti-âge » du sélénium / Evolution of skin equivalent models to improve the knowledge of skin aging mechanisms and validation of selenium efficiency as anti-aging

Jobeili, Lara 21 March 2018 (has links)
La peau et son vieillissement sont un enjeu de santé publique. Les modèles expérimentaux disponibles pour l'étude du vieillissement cutané restent perfectibles. Dans ce contexte, nos objectifs étaient simultanément d'utiliser les modèles de peaux reconstruites (PR) développés dans notre laboratoire afin i) de mieux comprendre les mécanismes du vieillissement cutané, ii) de démontrer l'efficacité et le mécanisme d'action du sélénium comme « anti âge » et enfin iii) de les faire évoluer en utilisant le support poreux ou auto-assemblé avec des fibroblastes du même donneur prélevés à des âges différents. Ainsi, le modèle de PR cultivé sur une longue période a montré une surexpression du microARN miR30-a par RT qPCR dans les PR « âgées » avec une altération de la fonction barrière mesurée par la perte insensible en eau et une perturbation de la différenciation terminale (baisse d'expression de la loricrine et de l'involucrine). Avec le même modèle in vitro, nos résultats démontrent que la supplementation en sélénium retarde la sénescence des kératinocytes souches. Cette efficacité passe non pas par un effet antioxydant comme attendu mais par l'activation de leur adhésion à la lame basale, qui participe à les conserver souche et donc à préserver le renouvellement épidermique. Enfin, nous avons eu la chance exceptionnelle de préparer des PR avec des fibroblastes provenant d'un donneur unique prélevé à 36 et 72 ans. Les résultats immunohistologiques montrent que l'âge induit une augmentation de l'expression de l'élastine et de la fibrilline ainsi que leur co-expression. L'augmentation de LTBP1 et aSMA suggère que cette augmentation inattendue est due à une dérégulation de la voie TGF-ß et une différenciation des fibroblastes en myofibroblastes. En conclusion l'utilisation de différents modèles de PR a permis d'explorer les mécanismes conduisant au vieillissement cutané et de démontrer l'efficacité du sélénium comme anti âge / Skin and its aging is a public health issue. In vitro skin models available for the study aging remain perfectible. In this context, our objectives were simultaneously to use skin equivalent (SE) developed in our laboratory i) to better understand mechanisms of skin aging, ii) to demonstrate the effectiveness of selenium as “anti-aging” and finally iii) to improve SE using the porous or scaffold free model with fibroblasts from the same donor at different ages. Thus, the model of SE mimicking senescence showed an overexpression of microRNA miR30-a by RT qPCR in old SE with an alteration of the barrier function measured by the transepidermal water loss and a deficiency of epidermal terminal differentiation (decreased expression of loricrin and involucrin). With the same SE model, our results demonstrate that selenium supplementation delays the senescence of keratinocytes stem cells. This effectiveness does not involve antioxidant effect as expected but the activation of their adhesion to the basement membrane, which participates in preserving stemness and epidermal renewal. Finally, we had the opportunity to prepare SE with fibroblasts from a single donor at 36 and 72 years old. The histological results show that age induces an increase in the expression of elastin and fibrillin as well as their co-expression. The increase of LTBP1 and aSMA suggests that this unexpected increase is due to deregulation of the TGF-ß pathway and fibroblasts differentiation into myofibroblasts. In conclusion, the use of different models of SE helps us to explore some mechanisms leading to skin aging and to demonstrate the efficacy of selenium as “anti-aging”
29

Estudo comparativo da pele pré e pós-laser fracionado minimamente ablativo com Erbium-YAG de 2940nm para tratamento de rítides da região perioral: avaliação clínica, anátomo-patológica e imuno-histoquímica / Comparative study of skin pre and post fractional photothermolysis with Erbium-YAG 2940nm for the treatment of perioral wrinkles: a clinical, histological and immunohistochemical analysis

Lilian Mayumi Odo 24 March 2010 (has links)
Atualmente existem diversas opções terapêuticas para o tratamento do fotoenvelhecimento cutâneo.Uma das formas de tratamento muito utilizada é a fototerapia com laser. Com o desenvolvimento da tecnologia em lasers surgiu um novo conceito de tratamento da pele envelhecida, a fototermólise fracionada microablativa. Essa tecnologia fracionada visa combinar os efeitos visíveis de uma terapia ablativa com o conforto e segurança dos métodos não ablativos. Antes de atingir a pele o laser passa por uma lente óptica especial que o divide em microrraios. Tal procedimento produz colunas de lesões térmicas microscópicas que penetram na epiderme e derme, sem danificar o tecido circunvizinho. A grande vantagem de ser fracionado é que a pele íntegra ao redor de cada coluna funciona como um reservatório de células potentes para a rápida cicatrização e regeneração da pele, culminando com a produção de colágeno e resultando em uma pele mais jovial, sem o inconveniente de um longo período de recuperação pós-tratamento. 20 pacientes foram selecionadas para o tratamento das rítides periorais com uma sessão de laser Erbium-YAG de 2940nm, fracionado. Após 28 dias do procedimento observou-se melhora na textura da pele, clareamento de manchas e atenuação de rugas finas periorais. Foi realizado um estudo comparativo da quantificação das células de Langerhans e receptores toll-like ( TLRs ) 2, 3 e 9 na epiderme, antes e após 3, 7, 14 e 28 dias do tratamento e da quantificação das fibras de colágeno na derme superior, antes e após 28 dias do laser. Houve diferenças estatisticamente significativas entre as medianas dos valores de CD1a (p = 0,0085), TLR 2 (p = 0,0108), TLR 3 (p = 0,0011) e TLR 9 (p = 0,0012) na epiderme pré e pós-tratamento. Foi constatado que a significância se deu entre os valores: antes e após 14 dias para CD1a (diminuição), antes e após 7 dias para TLR 2 (diminuição), antes e após 14 dias para TLR 3 (aumento), antes e após 7 dias para TLR 9 (diminuição). Não se encontraram diferenças estatisticamente significativas entre os valores medianos das fibras colágenas do tipo I (p = 1,0000) e III (p = 0,3125) antes e após 28 dias do tratamento. O protocolo desse estudo mostrou-se bastante seguro, pois apresentou efeitos colaterais transitórios e nenhuma complicação permanente. / There are several treatment options for skin photoaging. One of them widely used nowadays is lasertherapy. The development of lasers technology introduced a new therapeutic concept for aging skin: ablative fractional photothermolysis. This technology combines the visible effects of an ablative therapy with the comfort and safety of nonablative methods. Before reaching the skin the laser passes through a special optical lens that splits it into tiny rays. This procedure produces columns of microscopic thermal injuries that penetrate the epidermis and dermis, without damaging the surrounding tissue. The great advantage of the fractional photothermolysis is that the intact skin around each column acts as a potent reservoir of cells for fast healing and skin regeneration, resulting in collagen production and a youthful skin without the inconvenience of a long period of recovery after treatment. 20 patients were selected for perioral wrinkles treatment with a session of fractional Erbium-YAG 2940nm. After 28 days of the procedure the perioral skin showed improvement in texture, bleaching of sunspots and attenuation of superficial wrinkles. A comparative study was conducted between the expression of Langerhans cells and toll-like receptors 2, 3 and 9 in the epidermis, before and after 3,7,14 and 28 days of treatment and among collagen fibers in the dermis, before and after 28 days of the laser. There were statistically significant differences between the median values of CD1a (p = 0.0085), TLR 2 (p = 0.0108), TLR 3 (p = 0.0011) and TLR 9 (p = 0.0012) in the epidermis pre and post-treatment. The significance occurred between the values: before and after 14 days for CD1a (decrease) before and after 7 days to TLR 2 (decrease) before and after 14 days for TLR 3 (increase) before and after 7 days for TLR 9 (decrease). There were not statistically significant differences between the median values of collagen type I (p = 1.0000) and III (p = 0.3125) before and after 28 days of treatment. The irradiation of skin with fractional Erbium-YAG was safe, as it showed transitory side effects and no permanent complication.
30

Estudo da pele do campo cancerizável antes e após a terapia fotodinâmica através dos métodos clínicos, histopatológicos e imunohistoquímicos / Clinical, histopathological and immunohistochemical assessment of human skin field cancerization before and after photodynamic therapy

Luís Antonio Ribeiro Torezan 16 November 2011 (has links)
O conceito de campo de cancerização, em dermatologia, sugere que a pele fotodanificada tem maior potencial para o desenvolvimento de neoplasias cutâneas. A terapia fotodinâmica (TFD) é um método não invasivo para o tratamento de queratoses actínicas (QA) múltiplas, possibilitando a abordagem de todo o campo. Vinte e seis pacientes com múltiplas QAs na face foram submetidos a três sessões de TFD com metilaminolevulinato 16% (MAL) e luz vermelha, com intervalo de um mês. Biópsias foram realizadas antes e após três meses da última sessão e o material corado para hematoxilina-eosina e Weigert. O estudo imunohistoquímico foi feito para os marcadores: TP-53, pró-colageno I, Metaloproteinase-1 e Tenascina-C. A avaliação do fotoenvelhecimento global melhorou consideravelmente (p < 0,001) e a cura clínica das QAs foi de 89,5% ao final do estudo. Duas sessões mostraram ser equivalentes a três sessões de TFD. Diminuição significante do grau e extensão da atipia celular (p < 0,001), aumento das fibras colágenas (p = 0,001) e melhora do grau de elastose (p = 0,002) foram observadas. O estudo imunohistoquímico mostrou diminuição da expressão da TP-53 (p = 0,580), aumento de pró-colágeno I (p = 0,477) e de MMP-1 (p = 0,08), embora não houvesse diferença estatisticamente significante. Aumento significativo foi observado para Tenascina-C (p = 0,024). Múltiplas sessões de TFD com MAL induziram melhora clínica e histológica do campo de cancerização. A diminuição da severidade e extensão da atipia celular associada à menor expressão de TP-53 sugerem redução do potencial carcinogênico do campo / The field cancerization concept suggests that photodamaged skin has an increased risk for the development of malignant lesions. Topical photodynamic therapy (PDT) is a non-invasive therapeutic method for multiple actinic keratosis (AK), allowing the possibility of treating the entire surface. Twenty-six patients with photodamaged skin and multiple AKs on the face were submitted to three consecutive sessions of PDT with mehtylaminolevulinate 16% (MAL) and red light, one month apart. Biopsies were performed before and three months after the last treatment session, and stained for hematoxilin-eosin and Weigert. Immunohistochemestry study was performed for TP-53, pro-collagen I, Metalloproteinase-1 and Tenascin-C. The global score for photodamage improved considerably in all patients (p < 0.001). The AK clearance rate was 89.5% at the end of the study. Two treatments were similar to three MAL-PDT sessions. A significant decrease in keratinocytes atypia grade and amount was observed (p < 0.001). A significant increase in collagen deposition (p = 0.001) and improvement of solar elastosis (p = 0.002) were noticed. Immunohistochemical study showed decreased TP-53 expression although not statistically significant (p = 0.580), increased pro-collagen I and MMP-1 expressions (p = 0.477 and p = 0.08) again not statistically significant and a increased expression of Tenascin-C (p = 0.024), which was statistically significant. In conclusion, multiple sessions of MAL-PDT induced clinical and histological improvement of field cancerization. The decrease in severity and extension of keratinocytes atypia associated with a decreased expression of TP-53 suggest a reduced carcinogenic potential of the altered field

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