No description available.

No description available.

Bioengineered skin is a promising treatment for chronic skin wounds because of its ability to promptly promote wound healing at the injury site and to restore the skin’s epidermal and dermal structures and functions. Despite some level of clinical success, commercially available bioengineered skin substitutes are still limited by a high incidence of infection, a lack of mechanical integrity, and a slow rate of tissue ingrowth from the surrounding wound margin. To address these challenges, we propose to engineer novel polymer composite matrices for dermal regeneration. These matrices consist of two different electrospun polymer layers which create a composite matrix made up of a highly porous three-dimensional fibrous network. Each composite matrix contains a biodegradable electrospun “dermal” layer which acts as a scaffold for dermal cell ingrowth and tissue regeneration and a non-degradable electrospun “epidermal” layer that serves as a provisional barrier to protect the wound from environmental insult. To evaluate the success of our designs, we performed quantitative analyses of the physical properties of our electrospun scaffolds including fiber diameter and angle analyses and mechanical properties. We found our electrospun scaffolds are comprised of a random network of fibers ranging from approximately 0.2 – 5µm in diameter. They exhibit several mechanical properties that are similar to those measured in native skin tissue, including tangent elastic modulus and strain at failure. We have also found the proposed nanofibrous scaffolds to be capable of supporting normal human fibroblast attachment and migration. Our scaffolds show similar attachment to tissue culture polystyrene controls and better attachment than collagen-GAG sponge controls. The dermal layer of our scaffolds show fibroblast outgrowth rates between 185 - 206µm/day, which is similar to rates observed by others in collagen-GAG sponges and wounds. The promising findings from these in vitro studies warrant that our novel electrospun dermal regeneration matrix be further developed.

Bioengineered skin is a promising treatment for chronic skin wounds because of its ability to promptly promote wound healing at the injury site and to restore the skin’s epidermal and dermal structures and functions. Despite some level of clinical success, commercially available bioengineered skin substitutes are still limited by a high incidence of infection, a lack of mechanical integrity, and a slow rate of tissue ingrowth from the surrounding wound margin. To address these challenges, we propose to engineer novel polymer composite matrices for dermal regeneration. These matrices consist of two different electrospun polymer layers which create a composite matrix made up of a highly porous three-dimensional fibrous network. Each composite matrix contains a biodegradable electrospun “dermal” layer which acts as a scaffold for dermal cell ingrowth and tissue regeneration and a non-degradable electrospun “epidermal” layer that serves as a provisional barrier to protect the wound from environmental insult. To evaluate the success of our designs, we performed quantitative analyses of the physical properties of our electrospun scaffolds including fiber diameter and angle analyses and mechanical properties. We found our electrospun scaffolds are comprised of a random network of fibers ranging from approximately 0.2 – 5µm in diameter. They exhibit several mechanical properties that are similar to those measured in native skin tissue, including tangent elastic modulus and strain at failure. We have also found the proposed nanofibrous scaffolds to be capable of supporting normal human fibroblast attachment and migration. Our scaffolds show similar attachment to tissue culture polystyrene controls and better attachment than collagen-GAG sponge controls. The dermal layer of our scaffolds show fibroblast outgrowth rates between 185 - 206µm/day, which is similar to rates observed by others in collagen-GAG sponges and wounds. The promising findings from these in vitro studies warrant that our novel electrospun dermal regeneration matrix be further developed.

Made available in DSpace on 2014-06-11T19:26:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-12-20Bitstream added on 2014-06-13T18:29:20Z : No. of bitstreams: 1 degelo_gc_me_botib.pdf: 3122414 bytes, checksum: a43addf976b7ad3c68dbf541691be278 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Para que a integridade da pele seja mantida é necessário que haja distribuição de água nas camadas epidérmica e dérmica, manutenção das propriedades de barreira da pele, além da manutenção da integridade estrutural, elasticidade e resiliência deste tecido. O objetivo deste estudo foi avaliar se o extrato de Bidens pilosa é capaz de modular a expressão dos genes AQP3, AQP9, AQP10, filagrina, involucrina, fibronectina e se este extrato é capaz de aumentar a quantidade de colágeno, elastina e GAGs. Esta avaliação foi realizada através da técnica de PCR em tempo real, utilizando culturas queratinócitos comerciais incubadas com extrato hidroglicólico de Bidens pilosa (EHBP) na concentração de 5,00 mg/ml nos tempos de 0, 3, 6 e 12 horas e em diferentes concentrações do EHBP (2,50; 5,00 e 10,00 mg/ml) para a análise de expressão dos genes da epiderme, além do p53, importante supressor tumoral. Cultura de fibroblastos foram incubados também com o extrato por 48 horas para análise do EHBP sobre a produção de colágeno, elastina e GAGs. O tratamento das culturas de queratinócitos com EHBP no tempo de 6 horas em diferentes concentrações se mostrou capaz de modular positivamente a expressão dos genes AQP3, AQP9, fibronectina e involucrina, porém não foi possível a análise da expressão gênica da AQP10 e filagrina. A expressão de p53 não foi modulada pelo tratamento com EHBP nas concentrações de 2,50 e 5,00 mg/ml, além disso, o EHBP se mostrou eficaz em aumentar a quantidade proteínas dérmicas em sobrenadante de cultura de fibroblastos. Nosso trabalho sugere que o uso do extrato hidroglicólico de Bidens pilosa pode modular positivamente a expressão dos genes relacionados à hidratação da epiderme e integridade desta camada por modular genes de expressão tardia de diferenciação de queratinócitos, e integridade, elasticidade e resiliência... / To maintaining the integrity of the skin, it is necessary water distribution on epidermis and dermis, barrier properties of the skin maintenance, in addition to structural integrity maintenance, elasticity and tissue resilience. The aim of this study was evaluate if Bidens pilosa extract can modulate AQP3, AQP9, AQP10, filaggrin, involucrin, fibronectin expression and if this extract can improve collagen, elastin and GAGs. This evaluation was performed by real time PCR, with commercial keratinocytes incubated with hydroglycolic extract of Bidens pilosa (EHBP) at 5.0 mg/ml in times of 3, 6 e 12 hours and at different concentrations of EHBP (2.50, 5.00 and 10.00 mg/ml) to epidermal genes expression analyze, in addition to p53, a important tumor suppressor. Fibroblasts culture were also incubated with the extract for 48 hours to access the effect of EHBP on collagen, elastin and GAGs production. The culture keratinocytes treatment with EHBP with 6 hours of incubation with different concentrations of extract was capable to up-regulates AQP3, AQP9, fibronectina and involucrin gene expression, but it was not possible AQP10 and filaggrin gene expression analysis. The expression of p53 was not modulated by 2.50 and 5.00 mg/ml concentrations of EHBP, moreover, EHBP can increase dermal proteins amounts in fibroblasts culture supernatants. Our observation suggests that hydroglycolic extract of Bidens pilosa can modulate positively the expression of genes related with epidermal hydration and integrity of this layer because can modulate late expression on keratinocytes differentiation genes, and integrity, elasticity and resilience of skin by increasing amounts of dermal proteins and is unable to modulate p53 expression, suggesting absence of short-term correlation, between EHBP and cancer. Moreover, the lack of expression results to AQP10 puts in doubt the presence of this aquaglyceroporin... (Complete abstract click electronic access below)

The dermal barrier is the first line of defense for working animals, however, little is known on how it fluctuates and reacts to day-to-day events. Many are pursuing dermatological research including nutritional supplementation, decontamination strategies, and treatments of dermatological disease. However, without an in-depth understanding on how the dermal barrier and its resident microbiota fluctuate in response to the environment and basic maintenance practices, these research pursuits may lack accuracy. The presented works provide some preliminary insight into how common measures of dermal barrier such as cutaneous pH and trans-epidermal water loss (TEWL) fluctuate throughout the day and their natural response to changes in temperature and humidity in both acclimated and non-acclimated settings. Additionally, the works pursue how these dermal measures fluctuate following an antimicrobial bath with a common veterinary cleanser and if there are associations with the changes seen to the dermal microbiota. These findings have both implications for future research as well as for working animal decontamination procedures.

No description available.

No description available.

Orientador: Débora Colombi / Banca: Cláudia Aparecida Rainho / Banca: Aparecida Érica Bighetti Ribas / Resumo: Para que a integridade da pele seja mantida é necessário que haja distribuição de água nas camadas epidérmica e dérmica, manutenção das propriedades de barreira da pele, além da manutenção da integridade estrutural, elasticidade e resiliência deste tecido. O objetivo deste estudo foi avaliar se o extrato de Bidens pilosa é capaz de modular a expressão dos genes AQP3, AQP9, AQP10, filagrina, involucrina, fibronectina e se este extrato é capaz de aumentar a quantidade de colágeno, elastina e GAGs. Esta avaliação foi realizada através da técnica de PCR em tempo real, utilizando culturas queratinócitos comerciais incubadas com extrato hidroglicólico de Bidens pilosa (EHBP) na concentração de 5,00 mg/ml nos tempos de 0, 3, 6 e 12 horas e em diferentes concentrações do EHBP (2,50; 5,00 e 10,00 mg/ml) para a análise de expressão dos genes da epiderme, além do p53, importante supressor tumoral. Cultura de fibroblastos foram incubados também com o extrato por 48 horas para análise do EHBP sobre a produção de colágeno, elastina e GAGs. O tratamento das culturas de queratinócitos com EHBP no tempo de 6 horas em diferentes concentrações se mostrou capaz de modular positivamente a expressão dos genes AQP3, AQP9, fibronectina e involucrina, porém não foi possível a análise da expressão gênica da AQP10 e filagrina. A expressão de p53 não foi modulada pelo tratamento com EHBP nas concentrações de 2,50 e 5,00 mg/ml, além disso, o EHBP se mostrou eficaz em aumentar a quantidade proteínas dérmicas em sobrenadante de cultura de fibroblastos. Nosso trabalho sugere que o uso do extrato hidroglicólico de Bidens pilosa pode modular positivamente a expressão dos genes relacionados à hidratação da epiderme e integridade desta camada por modular genes de expressão tardia de diferenciação de queratinócitos, e integridade, elasticidade e resiliência... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: To maintaining the integrity of the skin, it is necessary water distribution on epidermis and dermis, barrier properties of the skin maintenance, in addition to structural integrity maintenance, elasticity and tissue resilience. The aim of this study was evaluate if Bidens pilosa extract can modulate AQP3, AQP9, AQP10, filaggrin, involucrin, fibronectin expression and if this extract can improve collagen, elastin and GAGs. This evaluation was performed by real time PCR, with commercial keratinocytes incubated with hydroglycolic extract of Bidens pilosa (EHBP) at 5.0 mg/ml in times of 3, 6 e 12 hours and at different concentrations of EHBP (2.50, 5.00 and 10.00 mg/ml) to epidermal genes expression analyze, in addition to p53, a important tumor suppressor. Fibroblasts culture were also incubated with the extract for 48 hours to access the effect of EHBP on collagen, elastin and GAGs production. The culture keratinocytes treatment with EHBP with 6 hours of incubation with different concentrations of extract was capable to up-regulates AQP3, AQP9, fibronectina and involucrin gene expression, but it was not possible AQP10 and filaggrin gene expression analysis. The expression of p53 was not modulated by 2.50 and 5.00 mg/ml concentrations of EHBP, moreover, EHBP can increase dermal proteins amounts in fibroblasts culture supernatants. Our observation suggests that hydroglycolic extract of Bidens pilosa can modulate positively the expression of genes related with epidermal hydration and integrity of this layer because can modulate late expression on keratinocytes differentiation genes, and integrity, elasticity and resilience of skin by increasing amounts of dermal proteins and is unable to modulate p53 expression, suggesting absence of short-term correlation, between EHBP and cancer. Moreover, the lack of expression results to AQP10 puts in doubt the presence of this aquaglyceroporin... (Complete abstract click electronic access below) / Mestre

Made available in DSpace on 2014-06-11T19:28:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-02-26Bitstream added on 2014-06-13T20:57:40Z : No. of bitstreams: 1 oliveira_ca_me_arafo.pdf: 227077 bytes, checksum: bd756a932166596c8abaefd6455879f6 (MD5) / O propósito deste estudo foi analisar histologicamente a utilização da matriz dérmica acelular (AlloDermâ) associada ou não à proteína derivada da matriz do esmalte (Emdogainâ) em recessões gengivais criadas cirurgicamente em cães. Foram criados defeitos periodontais na superfície vestibular dos caninos superiores de seis cães. Estes foram submetidos à indução do acúmulo de placa por oito semanas, e após este período foram divididos e tratados em dois grupos: grupo I: matriz dérmica acelular; grupo II: matriz dérmica acelular associada à proteína derivada da matriz do esmalte, ambos com reposição coronária do retalho. Após três meses os animais foram sacrificados, os dentes retirados em bloco e processados histologicamente. Realizou-se análise histológica descritiva e histométrica, medindo-se a extensão do tecido epitelial, neoformação óssea e cementária, nível gengival, inserção conjuntiva e tamanho do defeito para os grupos I e II. Os resultados demonstraram valores estatisticamente iguais para as médias dos valores de cemento: 0.06 mm e 0.32 mm; osso: -0,75 mm e -0,86 mm; nível gengival: -2,15 mm e -3,11 mm; tamanho do defeito: 4,90 mm e 5,51 mm, respectivamente para os grupos I e II. Foi encontrada diferença estatisticamente significante em relação tecido epitelial, com médias de 2,88 mm e 2,15 mm, respectivamente para os grupos I e II. Não foi encontrada inserção conjuntiva. Com isso, pudemos concluir que o Emdogainâ não trouxe efeitos adicionais quando associado ao AlloDermâ. / The purpose of the present study was to histologically evaluate the healing of acellular dermal matrix (AlloDermâ), associated or not, a enamel matrix proteins (Emdogainâ) in gingival recessions defects created in dogs. Recessions defects were surgically created (5X7 mm) on the buccal aspect of the uppercuspids in contralateral jaw quadrants, in 6 mongrel dogs. The defects were exposed to plaque accumulation for 2 months. After they were divided into 2 groups, according to the treatment applied: Group I- acellular dermal matrix and coronally positioned flap; Group II: acellular dermal matrix, enamel matrix proteins and coronally positioned flap. After 3 months, the animals were sacrificed, and the blocks obtained were processed. Histologic and histometric analysis were performed to examine: ephithelium formation, cementum and bone regeneration, connective tissue adaptation, attachment level and defect measure. Results did not show a statistically significant difference in the cementum and bone regeneration, connective tissue adaptation, attachment level and defect measure parameters. The mean values were: 0,06 mm and 0,32 mm for cementum regeneration; -0,75 mm and -0,86 mm for bone regeneration; -2,15mm and -3,11 mm for attachment level; and 4,90 mm and 5,51 mm for defect measure, in the I and II groups, respectively. The ephithelium formation parameter was 2,88 mm and 2,15 mm, in the I and II groups, respectively, with a statistically significant difference. Within limits of this study, it can be concluded that Emdogainâ not brought additional effects when associated with AlloDermâ.